4,137 results on '"Fluorenes"'
Search Results
2. DL-BETA-FLUOREN-4-YLALANINE.
- Author
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MORRISON DC
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- Chemical Phenomena, Alanine, Chemistry, Fluorenes, Research
- Published
- 1965
3. Selective photocatalytic oxidation of sulfides with dioxygen over carbazole–fluorene conjugated microporous polymers
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Xiaoyun Dong, Wenlong Sheng, Xianjun Lang, Hui Xu, and Huimin Hao
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Fluorenes ,Polymers ,Chemistry ,Carbazole ,Carbazoles ,Sulfides ,Fluorene ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Conjugated microporous polymer ,Oxygen ,Biomaterials ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Monomer ,Polymerization ,Polymer chemistry ,Photocatalysis ,Moiety ,Methanol - Abstract
One sustainable concept emerges to implement the selective oxidation of sulfides with dioxygen (O2) at ambient conditions and has received increasing attention. As such, three donor–acceptor (D–A) type conjugated microporous polymers (CMPs) were connected via robust C C bonds prepared from FeCl3-promoted polymerization of monomers of 3,6-di(9H-carbazol-9-yl)-9H-fluorene with the 9H position of the fluorene moiety occupied by 1,1′-biphenyl-, difluoro-, or keto- group, furnishing 9,9′-(9,9′-spirobi[fluorene]-2,7-diyl)-bis-9H-carbazole-CMP (SFC-CMP), 9,9′-(9,9-difluoro-9H-fluorene-2,7-diyl)bis(9H-carbazole)-CMP (FFC-CMP), and 2,7-di(carbazol-9-yl)-fluoren-9-one-CMP (OFC-CMP), respectively. These three carbazole–fluorene CMPs could implement blue light-driven highly selective oxidation of sulfides into sulfoxides with O2 in methanol (CH3OH). Intriguingly, the SFC-CMP imparted the best photocatalytic activity for selective oxidation of sulfides in a broad scope. Besides, the SFC-CMP photocatalyst could be fully recovered even outperforming the fresh one. This work highlights that the properties of CMPs could be regulated by the D–A units like carbazole–fluorene to execute selective chemical transformations ambiently.
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- 2022
4. Excited-State Dynamics of a Substituted Fluorene Derivative. The Central Role of Hydrogen Bonding Interactions with the Solvent
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James E. Jackson, Piotr Piecuch, Mehdi Moemeni, Aria Vahdani, Soham Maity, Babak Borhan, Marcos Dantus, Stephen H. Yuwono, Gary J. Blanchard, and Briana A. Capistran
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Fluorenes ,Chemistry ,Hydrogen bond ,Relaxation (NMR) ,Hydrogen Bonding ,Electronic structure ,Fluorene ,Photochemistry ,Article ,Surfaces, Coatings and Films ,Solvent ,chemistry.chemical_compound ,Spectrometry, Fluorescence ,Excited state ,Solvents ,Materials Chemistry ,Molecule ,Physical and Theoretical Chemistry ,Schiff Bases ,Derivative (chemistry) - Abstract
Substituted fluorene structures have demonstrated unusual photochemical properties. Previous reports on the substituted fluorene Schiff base FR0-SB demonstrated super photobase behavior with a ΔpK(b) of ~14 upon photoexcitation. In an effort to understand the basis for this unusual behavior, we have examined the electronic structure and relaxation dynamics of the structural precursor of FR0-SB, the aldehyde FR0, in protic and aprotic solvents using time-resolved fluorescence spectroscopy and quantum chemical calculations. The calculations show three excited singlet states in relatively close energetic proximity. The spectroscopic data are consistent with relaxation dynamics from these electronic states that depend on the presence and concentration of solvent hydroxyl functionality. These results underscore the central role of solvent hydrogen bonding to the FR0 aldehyde oxygen in mediating the relaxation dynamics within this molecule.
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- 2021
5. Selective Synthesis of Diverse Spiro-oxindole-fluorene Derivatives via a DABCO-Promoted Annulation Reaction of Bindone and 3-Methyleneoxindoles
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Jing Sun, Chao-Guo Yan, Dan Liu, and Xueyan Liu
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Reaction conditions ,Fluorenes ,Annulation ,Molecular Structure ,Organic Chemistry ,Diastereomer ,DABCO ,Fluorene ,Medicinal chemistry ,Piperazines ,Oxindoles ,chemistry.chemical_compound ,chemistry ,Indoline ,Spiro Compounds ,Oxindole ,Acetonitrile - Abstract
A DABCO-promoted annulation reaction of bindone ([1,2'-biindenylidene]-1',3,3'-trione) and 3-methyleneoxindoles showed very interesting molecular diversity under different reaction conditions. The base-promoted annulation reaction of bindone and 3-phenacylideneoxindoles in DCM at room temperature afforded spiro[indeno[1,2-a]fluorene-5,3'-indoline] derivatives in good yields and with high diastereoselectivity. However, the similar reaction of 2-(2-oxoindolin-3-ylidene) acetates resulted in Z/E-isomeric spiro[indeno[1,2-a]fluorene-5,3'-indolines] with diastereomeric ratios of 2:1 to 10:1. On the other hand, the DABCO-promoted annulation reaction of bindone and 3-methyleneoxindoles in acetonitrile at different temperatures selectively gave spiro[benzo[5,6]pentaleno[1,6a-b]naphthalene-7,3'-indoline] derivatives and complex dispiro[indoline-3,6'-[4b,6a]ethanoindeno[1,2-a]fluorene-14',3″-indolines] in satisfactory yields.
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- 2021
6. Binding interaction of a ring-hydroxylating dioxygenase with fluoranthene in Pseudomonas aeruginosa DN1
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Ya-Ni Liu, Jin-Cheng Pan, Yanling Ma, Shu-Wen Xue, and Yuexin Tian
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Stereochemistry ,Science ,Mutant ,Microbiology ,Article ,Dioxygenases ,Gene Knockout Techniques ,chemistry.chemical_compound ,Bacterial Proteins ,Dioxygenase ,Amino Acid Sequence ,Homology modeling ,G alpha subunit ,Fluoranthene ,Fluorenes ,Multidisciplinary ,biology ,Mutagenesis ,Active site ,Molecular Docking Simulation ,Environmental sciences ,chemistry ,Pseudomonas aeruginosa ,Mutagenesis, Site-Directed ,biology.protein ,Medicine ,Structural biology ,Ramachandran plot - Abstract
Pseudomonas aeruginosa DN1 can efficiently utilize fluoranthene as its sole carbon source, and the initial reaction in the biodegradation process is catalyzed by a ring-hydroxylating dioxygenase (RHD). To clarify the binding interaction of RHD with fluoranthene in the strain DN1, the genes encoding alpha subunit (RS30940) and beta subunit (RS05115) of RHD were functionally characterized through multi-technique combination such as gene knockout and homology modeling as well as molecular docking analysis. The results showed that the mutants lacking the characteristic alpha subunit and/or beta subunit failed to degrade fluoranthene effectively. Based on the translated protein sequence and Ramachandran plot, 96.5% of the primary amino-acid sequences of the alpha subunit in the modeled structure of the RHD were in the permitted region, 2.3% in the allowed region, but 1.2% in the disallowed area. The catalytic mechanism mediated by key residues was proposed by the simulations of molecular docking, wherein the active site of alpha subunit constituted a triangle structure of the mononuclear iron atom and the two oxygen atoms coupled with the predicted catalytic ternary of His217-His222-Asp372 for the dihydroxylation reaction with fluoranthene. Those amino acid residues adjacent to fluoranthene were nonpolar groups, and the C7-C8 positions on the fluoranthene ring were estimated to be the best oxidation sites. The distance of C7-O and C8-O was 3.77 Å and 3.04 Å respectively, and both of them were parallel. The results of synchronous fluorescence and site-directed mutagenesis confirmed the roles of the predicted residues during catalysis. This binding interaction could enhance our understanding of the catalytic mechanism of RHDs and provide a solid foundation for further enzymatic modification.
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- 2021
7. Safety and efficacy of sofosbuvir/ledipasvir and sofosbuvir/daclatasvir in the treatment of hepatitis C in patients with decompensated cirrhosis
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Amr Abbass, Ahmed Ghalwash, Heba Omar, Mohamed El Kassas, Mohamed Eltabbakh, Ahmad Sweedy, Sameera Ezzat, Hassan Hamdy, Shimaa Afify, Mohamed Salaheldin, Dalia Omran, Rasha Farghaly, Helmy Elshazly, Nermeen Abdeen, Marwa Tahoon, Mohamed Alboraie, and Mohammed Emadeldeen
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Liver Cirrhosis ,Ledipasvir ,medicine.medical_specialty ,Pyrrolidines ,Daclatasvir ,Genotype ,Sustained Virologic Response ,Sofosbuvir ,Hepatitis C virus ,Population ,Hepacivirus ,medicine.disease_cause ,Antiviral Agents ,Severity of Illness Index ,End Stage Liver Disease ,Liver disease ,chemistry.chemical_compound ,Internal medicine ,medicine ,Humans ,education ,Retrospective Studies ,Fluorenes ,education.field_of_study ,Hepatology ,business.industry ,Imidazoles ,Gastroenterology ,Valine ,Hepatitis C ,Hepatitis C, Chronic ,medicine.disease ,Decompensated cirrhosis ,Treatment Outcome ,chemistry ,Benzimidazoles ,Drug Therapy, Combination ,Carbamates ,business ,medicine.drug - Abstract
BACKGROUND Hepatitis C virus (HCV)-related decompensated cirrhosis is a severe life-threatening illness. The safety of direct-acting antivirals (DAAs) has opened a gate of hope for that subgroup of patients who were previously contraindicated for interferon therapy. OBJECTIVE We aimed at the investigation of the safety and efficacy of different DAAs regimens in the treatment of HCV-related decompensated cirrhosis patients, to determine sustained virological response (SVR)12 rates and to analyze the factors associated with response. METHODS A retrospective, single-center study including HCV-related decompensated cirrhosis patients who received DAAs. Demographic, laboratory and clinical data were analyzed. The SVR12 rate was the primary outcome measure. Secondary outcomes included the predictors of response, changes in the baseline model for end-stage liver disease and child-turcotte-pugh (CTP) scores, and fibroindices (APRI and fibrosis-4 index) at 12 weeks after treatment. RESULTS In total, 145 eligible patients (141 with CTP class B and 4 with class C) were enrolled in this study. SVR12 was achieved by 88.06% (118/134) of efficacy population on different DAAs regimens, Treatment was discontinued in 11 patients because of severe side effects without any deaths. Younger age showed a significant positive association with SVR12. CONCLUSIONS DAAs can be used for the treatment of HCV-related decompensated liver disease, with acceptable SVR12 rates and safety profiles.
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- 2021
8. Constructing a Facile Biocomputing Platform Based on Smart Supramolecular Hydrogel Film Electrodes with Immobilized Enzymes and Gold Nanoclusters
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Ruiqi Xiao, Wenting Wei, Huiqin Yao, Jiaxuan Li, Cong Xiao, and Hongyun Liu
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Materials science ,Immobilized enzyme ,Logic ,Metal Nanoparticles ,Nanotechnology ,Nanoclusters ,Computers, Molecular ,chemistry.chemical_compound ,Coordination Complexes ,Controlled NOT gate ,General Materials Science ,Diphenylalanine ,Electrodes ,Edetic Acid ,Horseradish Peroxidase ,Fluorescent Dyes ,Fluorenes ,Quenching (fluorescence) ,Hydrogels ,Dipeptides ,Enzymes, Immobilized ,Smart Materials ,chemistry ,Logic gate ,Electrode ,Gold ,Biosensor ,Copper - Abstract
Herein, fluorescent gold nanoclusters (AuNCs) and horseradish peroxidase (HRP) were simultaneously embedded into self-assembled dipeptide supramolecular films of N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) on the surface of ITO electrodes (Fmoc-FF/AuNCs/HRP) by using a simple single-step process. In the films, both the fluorescence property of AuNCs and the bioelectrocatalytic property of HRP were well maintained and could be reversibly regulated by pH-sensitive structural changes in the Fmoc-FF hydrogel films. Cu(II)/EDTA in the solution could lead to the aggregation/disaggregation of AuNCs and further quenching/dequenching the fluorescence signal from the films. Meanwhile, the blue complexes formed by Cu(II) and EDTA could produce a UV-vis signal in the solution. In addition, the coordinated Cu(II) in the films enhanced the electrocatalytic capacity toward the reduction of H2O2 and could switch the current signal. A biomolecular logic circuit was built based on the smart film electrode system by using pH, the concentrations of EDTA, Cu(II) and H2O2 as inputs, while the fluorescence intensity (FL), current (I) and UV-vis extinction (E) of the solution as outputs. Various logic devices were fabricated using the uniform platform, consisting of an encoder/decoder, demultiplexer, dual-transfer gate, keypad lock, digital comparator, half adder, and controlled NOT (CNOT) gate. Specifically, an electronic three-value logic gate, gullibility (ANY) gate, was first mimicked in this biocomputing system. This work not only demonstrated the construction of a new type of multivalued logic gate by using a dipeptide micromolecular matrix but also provided a new approach for designing sophisticated biologic functions, establishing smart multianalyte biosensing or fabricating biology information processing through the use of a simple film system.
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- 2021
9. Crystallographic studies of piperazine derivatives of 3-methyl-5-spirofluorenehydantoin in search of structural features of P-gp inhibitors
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Jadwiga Handzlik, Wojciech Nitek, Ewa Szymańska, and Ewa Żesławska
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Fluorenes ,ATP Binding Cassette Transporter, Subfamily B ,Molecular Structure ,Hydrogen bond ,Hydrogen Bonding ,Protonation ,Crystal structure ,Crystallography, X-Ray ,Imidazolidines ,Condensed Matter Physics ,Piperazines ,Inorganic Chemistry ,Mice ,Piperazine ,chemistry.chemical_compound ,Crystallography ,chemistry ,Heterocyclic Compounds ,Docking (molecular) ,Materials Chemistry ,Hydantoin derivatives ,Animals ,Homology modeling ,Physical and Theoretical Chemistry ,Monoclinic crystal system - Abstract
5-Spirofluorenehydantoin derivatives show efflux modulating, cytotoxic and antiproliferative effects in sensitive and resistant mouse T-lymphoma cells. In order to extend the knowledge available about the pharmacophoric features responsible for the glycoprotein P (P-gp) inhibitory properties of arylpiperazine derivatives of 3-methyl-5-spirofluorenehydantoin, we have performed crystal structure analyses for 1-[3-(3′-methyl-2′,4′-dioxospiro[fluorene-9,5′-imidazolidin]-1′-yl)propyl]-4-phenylpiperazine-1,4-diium dichloride monohydrate, C29H32N4O2 2+·2Cl−·H2O (1), 3′-methyl-1′-{3-[4-(4-nitrophenyl)piperazin-1-yl]propyl}spiro[fluorene-9,5′-imidazolidine]-2′,4′-dione, C29H29N5O4·H2O (2), 3′-methyl-1′-{5-[4-(4-nitrophenyl)piperazin-1-yl]pentyl}spiro[fluorene-9,5′-imidazolidine]-2′,4′-dione, C31H33N5O4 (3), and 1-benzyl-4-[5-(3′-methyl-2′,4′-dioxospiro[fluorene-9,5′-imidazolidin]-1′-yl)pentyl]piperazine-1,4-diium dichloride 0.613-hydrate, C32H38N4O2 2+·2Cl−·0.613H2O (4). Structure 3 is anhydrous but the other three structures crystallize with water present. The investigated compounds crystallize in the monoclinic crystal system, with the space group P21/n for 1 and 3, and P21/c for 2 and 4. The cations of salts 1 and 4 are doubly protonated, with the protons located on the N atoms of the piperazine rings. The packing of 1 and 4 in the crystals is dominated by intermolecular N—H...Cl and O—H...Cl hydrogen bonds. In the crystal structure of 2, the intermolecular interactions are dominated by O—H...O and O—H...N hydrogen bonds, while in 3, which is lacking in classic hydrogen-bond donors, it is C—H...O contacts that dominate. Additionally, we have performed induced-fit docking studies for the investigated compounds docked to the P-gp human homology model.
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- 2021
10. Treatment of viral hepatitis C genotypes 1 and 2 by sofosbuvir and ledipasvir with or without ribavirin combination: A possible alternative to pangenotypic treatment in a low-income country?
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Andry Lalaina Rinà Rakotozafindrabe, Soloniaina Hélio Razafimahefa, Nitah Harivony Randriamifidy, Anjaramalala Sitraka Rasolonjatovo, Rado Manitrala Ramanampamonjy, T.H. Rabenjanahary, and Chantelli Iamblaudiot Razafindrazoto
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Male ,0301 basic medicine ,Cirrhosis ,Sofosbuvir ,Hepacivirus ,Infectious and parasitic diseases ,RC109-216 ,medicine.disease_cause ,Gastroenterology ,chemistry.chemical_compound ,0302 clinical medicine ,Genotype ,Medicine ,Drug Interactions ,Viral hepatitis C ,030212 general & internal medicine ,General Medicine ,Middle Aged ,Hepatitis C ,Treatment Outcome ,Infectious Diseases ,Ledipasvir ,Viral hepatitis ,medicine.drug ,Adult ,Microbiology (medical) ,Low income ,medicine.medical_specialty ,Hepatitis C virus ,030106 microbiology ,Antiviral Agents ,Young Adult ,03 medical and health sciences ,Internal medicine ,Ribavirin ,Madagascar ,Humans ,Developing Countries ,Aged ,Retrospective Studies ,Fluorenes ,business.industry ,medicine.disease ,chemistry ,Benzimidazoles ,business - Abstract
Objectives The aim of this study was to evaluate the efficacy and safety of sofosbuvir/ledipasvir ± ribavirin in Malagasy patients with hepatitis C virus genotypes 1 and 2, in real conditions. Patients and methods This was a retrospective monocentric clinical study, carried out over a period of 3 years from March 1, 2017 to February 28, 2020, in a hospital hepato-gastroenterology department. Results In total, 26 patients (M/F: 11/15) with hepatitis C virus genotype 1 (n = 13) or genotype 2 (n = 13), were treated with sofosbuvir/ledipasvir without (n = 21) or with (n = 5) ribavirin for 12 weeks. The mean age was 61.38 ± 7.09 years. Seventeen patients (65.4%) had cirrhosis. The overall sustained virological response was 96.2% (95% CI = 80.4–99.9%). There was no significant difference between the sustained virological responses of genotypes 1 and 2 (92.3% vs 100%; p = 0.31) or those of cirrhotic or non-cirrhotic patients (94.1% vs 100%; p = 0.46). A relapse was observed in one patient (5.9%) — cirrhotic and genotype 1b — under sofosbuvir/ledipasvir with ribavirin. Seven patients (26.9%) experienced mild adverse reactions, including asthenia (57.1%) and insomnia (42.9%). Conclusion Treatment with sofosbuvir/ledipasvir ± ribavirin for infection with hepatitis C virus genotype 1 has been shown to be safe and effective, even in the presence of cirrhosis. The sofosbuvir/ledipasvir combination is a good option for genotype 2 non-cirrhotic patients.
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- 2021
11. Improvement in Liver Stiffness in Pediatric Patients with Hepatitis C Virus after Treatment with Direct Acting Antivirals
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Noha A.E. Yasin, Shereen Abdel Alem, Engy A. Mogahed, Hadeel Gamal Eldeen, Ahmed Nagy, Hala Abdullatif, Hanaa M. El-Karaksy, and Mona S. El-Raziky
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Liver Cirrhosis ,Male ,Ledipasvir ,medicine.medical_specialty ,Adolescent ,Genotype ,Sofosbuvir ,Hepatitis C virus ,medicine.disease_cause ,Antiviral Agents ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Fibrosis ,030225 pediatrics ,Internal medicine ,Humans ,Medicine ,Aspartate Aminotransferases ,Prospective Studies ,030212 general & internal medicine ,Child ,Prospective cohort study ,Fluorenes ,business.industry ,Hepatitis C ,Hepatitis C, Chronic ,medicine.disease ,chemistry ,Pediatrics, Perinatology and Child Health ,Elasticity Imaging Techniques ,Benzimidazoles ,Female ,business ,Transient elastography ,Hepatic fibrosis ,medicine.drug - Abstract
To assess the degree of liver stiffness using transient elastography in Egyptian children infected with hepatitis C virus (HCV) at baseline and 1 year after achievement of sustained virologic response (SVR) with direct acting antivirals.This prospective study included children infected with HCV who received treatment with sofosbuvir/ledipasvir and achieved SVR. At baseline and 1 year after achievement of SVR, the extent of hepatic fibrosis was assessed by transient elastography using FibroScan to measure liver stiffness, in addition to noninvasive markers including aspartate aminotransferase/platelet ratio index (APRI) and fibrosis-4 (FIB-4) index.The study included 23 cases that had variable degrees of fibrosis at baseline; their ages ranged between 10 and 18 years. At baseline, 13 patients had F1; 3 patients had F1-F2; 1 patient had F2; 3 patients had F3; 2 had F3-F4; and 2 patients with F4. One year after achievement of SVR, there was a statistically significant improvement in liver stiffness, APRI, and FIB-4 index (P = .03,.001, .02, respectively). In 13 patients (56.5%), the liver stiffness improved; in 7 patients, it was stationary; and the remaining 3 patients showed mild increase in liver stiffness that was, however, associated with improvement in APRI and FIB-4 index. Comorbid conditions and previous treatment with interferon were not associated with increased liver stiffness 1 year after SVR.Egyptian children infected with HCV genotype 4 achieved significant regression in liver stiffness after treatment with direct acting antivirals.
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- 2021
12. Ledipasvir/Sofosbuvir for 8, 12, or 24 Weeks in Hepatitis C Patients Undergoing Dialysis for End-Stage Renal Disease
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Cheng Yuan Peng, Hadas Dvory-Sobol, Sophia Lu, Peter Buggisch, Wan-Long Chuang, Anuj Gaggar, Christophe Moreno, Alessandra Mangia, Anu Osinusi, Luigi Biancone, Marianne Camargo, Meghan E. Sise, Tsung Hui Hu, Chen-Hua Liu, Brian J. Kirby, Wei Wen Su, and Robert H. Hyland
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Adult ,Male ,Ledipasvir ,medicine.medical_specialty ,Sustained Virologic Response ,Sofosbuvir ,medicine.medical_treatment ,Hepatitis C virus ,medicine.disease_cause ,Antiviral Agents ,Drug Administration Schedule ,End stage renal disease ,chemistry.chemical_compound ,Internal medicine ,medicine ,Humans ,Adverse effect ,Dialysis ,Aged ,Aged, 80 and over ,Fluorenes ,Hepatology ,business.industry ,Gastroenterology ,Hepatitis C ,Middle Aged ,medicine.disease ,Discontinuation ,Treatment Outcome ,chemistry ,Kidney Failure, Chronic ,Benzimidazoles ,Female ,business ,medicine.drug - Abstract
Introduction We evaluated 8, 12, or 24 weeks of ledipasvir/sofosbuvir in patients with hepatitis C virus and end-stage renal disease undergoing dialysis. Methods Primary efficacy end point was sustained virologic response 12 weeks after treatment. Primary safety end point was treatment discontinuation because of adverse events (AEs). Results Ninety-four percent (89/95) achieved sustained virologic response 12 weeks after treatment. Six patients died during treatment (n = 4) or before study completion (n = 2); no deaths were related to treatment. No patients discontinued treatment because of AEs. Thirteen percent had serious AEs; none were related to treatment. Discussion Treatment with ledipasvir/sofosbuvir was safe and effective in patients with end-stage renal disease undergoing dialysis.
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- 2021
13. RO4929097 regulates RANKL-induced osteoclast formation and LPS-mediated bone resorption
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Tao Huang, Yi Zhao, Congyun Zhao, Lei Wang, Yuan Zhou, and Donghua Hang
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Lipopolysaccharides ,MAPK/ERK pathway ,Aging ,Notch ,Osteolysis ,RO4929097 ,Osteoclasts ,Bone resorption ,Mice ,Osteogenesis ,Osteoclast ,In vivo ,medicine ,Animals ,Fluorenes ,biology ,Chemistry ,Macrophages ,RANKL ,Cell Differentiation ,Cell Biology ,Benzazepines ,Ketones ,medicine.disease ,Resorption ,medicine.anatomical_structure ,biology.protein ,Cancer research ,Amyloid precursor protein secretase ,bone resorption ,Research Paper ,Signal Transduction - Abstract
To investigate the suppressive function of RO4929097, a potent -secretase inhibitor, on RANKL-induced osteoclastogenesis. The cytotoxicity of RO4929097 was evaluated. The suppressive effect and possible molecular mechanism of RO4929097 on RANKL-induced osteoclastogenesis was evaluated both in vitro and in vivo. The IC50 of RO4929097 was 2.93 μM. Treatment with different doses of RO4929097 (100 nM, 200 nM, and 400 nM) effectively reduced osteoclast formation (number and resorption area) in a dose-dependent manner. The qPCR results revealed that RO4929097 attenuates RANKL-induced osteoclast formation and NFATc1 protein expression. The in vivo experiments demonstrated that RO4929097 had an inhibitory effect on LPS-induced bone resorption. Our in vitro experiments showed that RO4929097 can potently inhibit osteoclastogenesis and bone resorption by down-regulating the Notch/MAPK/JNK/Akt-mediated reduction of NFATc1. In accordance with these in vitro observations, RO4929097 attenuated LPS-induced osteolysis in mice. In conclusion, our findings indicate that Notch may represent a potential therapeutic target for the treatment of osteolytic diseases.
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- 2021
14. Appropriate aglycone modification significantly expands the glycan substrate acceptability of α1,6-fucosyltransferase (FUT8)
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Kelley W. Moremen, Lai-Xi Wang, Guanghui Zong, Chao Li, Jeong-Yeh Yang, Roushu Zhang, Bhargavi M. Boruah, Qiang Yang, and Digantkumar Chapla
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Glycan ,Glycosylation ,Ovalbumin ,Stereochemistry ,Gene Expression ,Peptide ,Context (language use) ,HIV Envelope Protein gp120 ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Article ,Substrate Specificity ,03 medical and health sciences ,chemistry.chemical_compound ,Polysaccharides ,Glycosyltransferase ,Animals ,Humans ,Moiety ,Erythropoietin ,Molecular Biology ,Fucosylation ,Fucose ,Glycoproteins ,030304 developmental biology ,chemistry.chemical_classification ,Fluorenes ,0303 health sciences ,biology ,Granulocyte-Macrophage Colony-Stimulating Factor ,Substrate (chemistry) ,Cell Biology ,Fucosyltransferases ,Peptide Fragments ,0104 chemical sciences ,carbohydrates (lipids) ,Kinetics ,HEK293 Cells ,Aglycone ,Carbohydrate Sequence ,chemistry ,HIV-1 ,biology.protein ,Chickens ,Mannose - Abstract
The α1,6-fucosyltransferase, FUT8, is the sole enzyme catalyzing the core-fucosylation of N-glycoproteins in mammalian systems. Previous studies using free N-glycans as acceptor substrates indicated that a terminal β1,2-GlcNAc moiety on the Man-α1,3-Man arm of N-glycan substrates is required for efficient FUT8-catalyzed core-fucosylation. In contrast, we recently demonstrated that, in a proper protein context, FUT8 could also fucosylate Man5GlcNAc2 without a GlcNAc at the non-reducing end. We describe here a further study of the substrate specificity of FUT8 using a range of N-glycans containing different aglycones. We found that FUT8 could fucosylate most of high-mannose and complex-type N-glycans, including highly branched N-glycans from chicken ovalbumin, when the aglycone moiety is modified with a 9-fluorenylmethyloxycarbonyl (Fmoc) moiety or in a suitable peptide/protein context, even if they lack the terminal GlcNAc moiety on the Man-α1,3-Man arm. FUT8 could also fucosylate paucimannose structures when they are on glycoprotein substrates. Such core-fucosylated paucimannosylation is a prominent feature of lysosomal proteins of human neutrophils and several types of cancers. We also found that sialylation of N-glycans significantly reduced their activity as a substrate of FUT8. Kinetic analysis demonstrated that Fmoc aglycone modification could either improve the turnover rate or decrease the KM value depending on the nature of the substrates, thus significantly enhancing the overall efficiency of FUT8 catalyzed fucosylation. Our results indicate that an appropriate aglycone context of N-glycans could significantly broaden the acceptor substrate specificity of FUT8 beyond what has previously been thought.
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- 2021
15. Resistance-associated substitutions and response to treatment in a chronic hepatitis C virus infected-patient: an unusual virological response case report
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Martín Soñora, Daniela Chiodi, Pablo López, Juan Cristina, Pilar Moreno, Natalia Echeverría, Fabián Aldunate, Gonzalo Moratorio, Nelia Hernández, Adriana Sánchez-Cicerón, Aldunate Caramori Fabián, Universidad de la República (Uruguay). Facultad de Ciencias. Centro de Investigaciones Nucleares., Echeverría Chagas Natalia, Universidad de la República (Uruguay). Facultad de Ciencias. Centro de Investigaciones Nucleares., Chiodi Daniela, Universidad de la República (Uruguay). Facultad de Medicina., López Pablo, Universidad de la República (Uruguay). Facultad de Medicina., Sánchez-Cicerón Adriana, Universidad de la República (Uruguay). Facultad de Medicina., Soñora Martín, Universidad de la República (Uruguay). Facultad de Ciencias. Centro de Investigaciones Nucleares., Cristina Juan, Universidad de la República (Uruguay). Facultad de Ciencias. Centro de Investigaciones Nucleares., Moratorio Gonzalo, Universidad de la República (Uruguay). Facultad de Ciencias. Centro de Investigaciones Nucleares., Hernández Nelia, Universidad de la República (Uruguay). Facultad de Medicina., and Moreno Karlen María del Pilar, Universidad de la República (Uruguay). Facultad de Ciencias. Centro de Investigaciones Nucleares.
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Male ,0301 basic medicine ,Ledipasvir ,Genotype ,Sustained Virologic Response ,Hepatitis C virus ,Hepacivirus ,Infectious and parasitic diseases ,RC109-216 ,medicine.disease_cause ,Antiviral Agents ,Virus ,03 medical and health sciences ,chemistry.chemical_compound ,symbols.namesake ,0302 clinical medicine ,Recurrence ,Pegylated interferon ,Drug Resistance, Viral ,Ribavirin ,Case report ,medicine ,Humans ,Relapse ,NS5A ,NS5B ,Sanger sequencing ,Fluorenes ,business.industry ,High-Throughput Nucleotide Sequencing ,Hepatitis C, Chronic ,Middle Aged ,Virology ,030104 developmental biology ,Infectious Diseases ,chemistry ,DAA therapy ,symbols ,RASs minority variants ,RNA, Viral ,Benzimidazoles ,Drug Therapy, Combination ,030211 gastroenterology & hepatology ,Sofosbuvir ,business ,medicine.drug - Abstract
Background Direct-Acting agents (DAAs) target and inhibit essential viral replication proteins. They have revolutionized the treatment of Hepatitis C virus (HCV) infection reaching high levels of sustained virologic response. However, the detection of basal resistance-associated substitutions (RASs) to DAAs in naïve patients could be important in predicting the treatment outcome in some patients exhibiting failures to DAA-based therapies. Therefore, the aim of this work was to evaluate the presence of RASs as minority variants within intra-host viral populations, and assess their relationship to response to therapy on a multiple times relapser patient infected chronically with HCV. Case presentation A male HCV infected-patient with a genotype 1a strain was evaluated. He had previously not responded to dual therapy (pegylated interferon-α plus ribavirin) and was going to start a direct-acting agent-based therapy (DAAs). He showed no significant liver fibrosis (F0). Viral RNA was extracted from serum samples taken prior and after therapy with DAAs (sofosbubir/ledipasvir/ribavirin). NS5A and NS5B genomic regions were PCR-amplified and the amplicons were sequenced using Sanger and next-generation sequencing (NGS) approaches. RASs were searched in in-silico translated sequences for all DAAs available and their frequencies were determined for those detected by NGS technology. Sanger sequencing did not reveal the presence of RASs in the consensus sequence neither before nor after the DAA treatment. However, several RASs were found at low frequencies, both before as well as after DAA treatment. RASs found as minority variants (particularly substitutions in position 93 within NS5A region) seem to have increased their frequency after DAA pressure. Nevertheless, these RASs did not become dominant and the patient still relapsed, despite perfect adherence to treatment and having no other complications beyond the infection (no significant fibrosis, no drug abuse). Conclusions This report shows that some patients might relapse after a DAA-based therapy even when RASs (pre- and post-treatment) are detected in very low frequencies (
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- 2021
16. Human Mass Balance and Metabolite Profiling of [14C]‐Pamiparib, a Poly (ADP‐Ribose) Polymerase Inhibitor, in Patients With Advanced Cancer
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Heather Zhang, Dan Su, Daniel H. Palmer, Zhiyu Tang, Claudia Andreu-Vieyra, Song Mu, Srikumar Sahasranaman, and Richard Fitzgerald
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Male ,medicine.medical_specialty ,CYP3A ,Metabolite ,Cmax ,Pharmaceutical Science ,DNA repair ,Original Manuscript ,Urine ,Poly(ADP-ribose) Polymerase Inhibitors ,030226 pharmacology & pharmacy ,Excretion ,Cytochrome P-450 CYP2C8 ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pharmacokinetics ,metabolite identification ,Internal medicine ,Neoplasms ,medicine ,Cytochrome P-450 CYP3A ,Humans ,Pharmacology (medical) ,Fluorenes ,biology ,business.industry ,pamiparib ,Cytochrome P450 ,Metabolism ,Articles ,Middle Aged ,Endocrinology ,Phenotype ,chemistry ,030220 oncology & carcinogenesis ,biology.protein ,Female ,absorption/metabolism/excretion ,business ,pharmacokinetics ,Half-Life - Abstract
Pamiparib, a selective poly (ADP‐ribose) polymerase 1/2 inhibitor, demonstrated tolerability and antitumor activity in patients with solid tumors at 60 mg orally twice daily. This phase 1 open‐label study (NCT03991494; BGB‐290‐106) investigated the absorption, metabolism, and excretion (AME) of 60 mg [14C]‐pamiparib in 4 patients with solid tumors. The mass balance in excreta, blood, and plasma radioactivity and plasma pamiparib concentration were determined along with metabolite profiles in plasma, urine, and feces. Unchanged pamiparib accounted for the most plasma radioactivity (67.2% ± 10.2%). Pamiparib was rapidly absorbed with a median time to maximum plasma concentration (Cmax) of 2.00 hours (range, 1.00‐3.05 hours). After reaching Cmax, pamiparib declined in a biphasic manner, with a geometric mean terminal half‐life (t1/2) of 28.7 hours. Mean cumulative [14C]‐pamiparib excretion was 84.7% ± 3.5%. Pamiparib was mainly cleared through metabolism, primarily via N‐oxidation and oxidation of the pyrrolidine ring. A dehydrogenated oxidative product (M3) was the most abundant metabolite in biosamples. A mean of 2.11% and 1.11% of [14C]‐pamiparib was excreted as unchanged pamiparib in feces and urine, respectively, indicating near‐complete absorption and low renal clearance of parent drug. Cytochrome P450 (CYP) phenotyping demonstrated CYP2C8 and CYP3A involvement in pamiparib metabolism. These findings provide an understanding of pamiparib AME mechanisms and potential drug‐drug interaction liability.
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- 2021
17. Effectiveness and safety of ledipasvir/sofosbuvir for genotype 2 chronic hepatitis C infection: Real-world experience from Taiwan
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Er-Hsiang Yang, Pin-Nan Cheng, I-Chin Wu, Yen-Cheng Chiu, Hung-Chih Chiu, Ting-Tsung Chang, Shih-Chieh Chien, and Chun-Hsien Wu
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Ledipasvir ,medicine.medical_specialty ,Genotype ,Sofosbuvir ,Hepatitis C virus ,Taiwan ,Hepacivirus ,medicine.disease_cause ,Chronic hepatitis C ,Antiviral Agents ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Ribavirin ,medicine ,Humans ,Ledipasvir/sofosbuvir ,Adverse effect ,Fluorenes ,lcsh:R5-920 ,business.industry ,General Medicine ,Hepatitis C, Chronic ,medicine.disease ,genotype 2 HCV ,Discontinuation ,Regimen ,Treatment Outcome ,chemistry ,030220 oncology & carcinogenesis ,Benzimidazoles ,Drug Therapy, Combination ,030211 gastroenterology & hepatology ,business ,lcsh:Medicine (General) ,Kidney disease ,medicine.drug - Abstract
Background/Purpose Genotype 2 (GT2) hepatitis C virus infection is the second common genotype in Taiwan. Real-world experience of ledipasvir/sofosbuvir (LDV/SOF) for GT2 infection is limited. The aim of this study is to evaluate the effectiveness and safety of LDV/SOF in patients with GT2 chronic hepatitis C (CHC) infection. Methods CHC patients with GT2 infection receiving 12 weeks LDV/SOF from three hospitals were enrolled. HCV RNA was checked at baseline, end-of-treatment and 12 weeks after completing treatment. Demographic data, adverse events, renal function and metabolic profiles were recorded. Results Among 392 enrolled patients, 33 patients (8.4%) were cirrhotic. Sustained virological response (SVR) rate was 96.7% (379/392) by intention-to-treat analysis and 97.2% (379/390) by per-protocol analysis. The SVR rate was lower in cirrhotic patients than in non-cirrhotic patients (90.6% vs 97.8%, p = 0.053). Two cirrhotic patients who took LDV/SOF plus ribavirin both achieved SVR. Neither drug-related severe adverse events nor discontinuation due to drug-related adverse event were reported. The estimated glomerular filtration rate (eGFR) remained stable in patients with chronic kidney disease 3a/3b. Conclusion Twelve weeks of LDV/SOF treatment provided an excellent and safe regimen for GT2 CHC infection, particularly in non-cirrhotic patients.
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- 2021
18. Improvement of Skeletal Muscle Mass after Ledipasvir and Sofosbuvir Treatment for Hepatitis C Virus in Decompensated Liver Cirrhosis
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Ryoko Yamada, Ryotaro Sakamori, Hayato Hikita, Kazuma Shinkai, Tomomi Yamada, Takahiro Kodama, Yuki Tahata, Minoru Shigekawa, Akira Doi, Tetsuo Takehara, and Tomohide Tatsumi
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Ledipasvir ,Liver Cirrhosis ,medicine.medical_specialty ,Cirrhosis ,ledipasvir ,Sofosbuvir ,direct-acting antiviral (DAA) ,Hepatitis C virus ,Case Report ,Hepacivirus ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Gastroenterology ,sofosbuvir ,Antiviral Agents ,sarcopenia ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Internal Medicine ,medicine ,Humans ,In patient ,Muscle, Skeletal ,Aged ,Fluorenes ,business.industry ,virus diseases ,General Medicine ,Hepatitis C, Chronic ,medicine.disease ,Skeletal muscle mass ,Hepatitis C ,digestive system diseases ,Treatment Outcome ,chemistry ,skeletal muscle index (SMI) ,Sarcopenia ,Quality of Life ,030211 gastroenterology & hepatology ,Benzimidazoles ,Female ,Liver function ,business ,medicine.drug ,decompensated liver cirrhosis - Abstract
Hepatitis C virus (HCV) can be eliminated by direct-acting antivirals in patients with decompensated liver cirrhosis. Although viral clearance in decompensated liver cirrhosis leads to improvement of the liver function and quality of life, changes in the skeletal muscle mass after sustained virologic response (SVR) in patients with decompensated liver cirrhosis have not been reported. We present the first report of skeletal muscle mass improvement with the achievement of SVR for HCV in a 76-year-old woman with decompensated liver cirrhosis. After achieving SVR through ledipasvir/sofosbuvir treatment, the patient showed an improvement in her liver function and an increase in her skeletal muscle mass.
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- 2021
19. Dolutegravir pharmacokinetics during co-administration with either artemether/lumefantrine or artesunate/amodiaquine
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Stephen Walimbwa, Aida N Kawuma, Saye Khoo, Roeland E Wasmann, Mohammed Lamorde, Goonaseelan Pillai, and Paolo Denti
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0301 basic medicine ,Microbiology (medical) ,Artemether/lumefantrine ,Pyridones ,030106 microbiology ,Population ,Artesunate ,Amodiaquine ,Pharmacology ,Lumefantrine ,030226 pharmacology & pharmacy ,Piperazines ,Antimalarials ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Oxazines ,medicine ,Humans ,Pharmacology (medical) ,Artemether ,Malaria, Falciparum ,education ,Fluorenes ,education.field_of_study ,business.industry ,Artemether, Lumefantrine Drug Combination ,Artesunate/amodiaquine ,Drug Combinations ,Infectious Diseases ,chemistry ,Ethanolamines ,Africa ,Dolutegravir ,business ,Heterocyclic Compounds, 3-Ring ,medicine.drug - Abstract
Background In sub-Saharan Africa, artemisinin-containing therapies for malaria treatment are regularly co-administered with ART. Currently, dolutegravir-based regimens are recommended as first-line therapy for HIV across most of Africa. Objectives To investigate the population pharmacokinetics of dolutegravir during co-administration with artemether/lumefantrine or artesunate/amodiaquine, two commonly used antimalarial therapies. Methods We developed a population pharmacokinetic model of dolutegravir with data from 26 healthy volunteers in two Phase 2 studies with a total of 403 dolutegravir plasma concentrations at steady state. Volunteers received 50 mg of dolutegravir once daily alone or in combination with standard treatment doses of artemether/lumefantrine (80/480 mg) or artesunate/amodiaquine (200/540 mg). Results A two-compartment model with first-order elimination and transit compartment absorption best described the concentration–time data of dolutegravir. Typical population estimates for clearance, absorption rate constant, central volume, peripheral volume and mean absorption transit time were 0.713 L/h, 1.68 h−1, 13.2 L, 5.73 L and 1.18 h, respectively. Co-administration of artemether/lumefantrine or artesunate/amodiaquine increased dolutegravir clearance by 10.6% (95% CI 4.09%–34.5%) and 26.4% (95% CI 14.3%–51.4%), respectively. Simulations showed that simulated trough concentrations of dolutegravir alone or in combination with artemether/lumefantrine or artesunate/amodiaquine are maintained above the dolutegravir protein-adjusted IC90 of 0.064 mg/L for more than 99% of the individuals. Conclusions Dolutegravir dose adjustments are not necessary for patients who are taking standard 3 day treatment doses of artemether/lumefantrine or artesunate/amodiaquine.
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- 2021
20. 'If I Get Cured, My Whole Quality of Life Will Change': Patients’ Anticipated and Actualized Benefits Following Cure from Chronic Hepatitis C
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Jessica Carda-Auten, Carol E. Golin, Donna M. Evon, Michael W. Fried, Hannah P. Kim, Bryce B. Reeve, and Angela Edwards
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Male ,Ledipasvir ,medicine.medical_specialty ,Sofosbuvir ,Physiology ,Social Interaction ,Stigma (botany) ,Antiviral Agents ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Quality of life (healthcare) ,Disease Transmission, Infectious ,medicine ,Humans ,Disease Eradication ,Fluorenes ,Motivation ,business.industry ,Gastroenterology ,Hepatitis C ,Hepatitis C, Chronic ,Middle Aged ,Anticipation, Psychological ,medicine.disease ,Mental Health ,Treatment Outcome ,Mood ,chemistry ,030220 oncology & carcinogenesis ,Quality of Life ,Anxiety ,Benzimidazoles ,Female ,030211 gastroenterology & hepatology ,Outcomes research ,medicine.symptom ,business ,medicine.drug ,Clinical psychology - Abstract
BACKGROUND: Patients’ motivations for undergoing direct-acting antiviral (DAA) therapy for chronic hepatitis C may include anticipation of treatment benefits not well-described in the literature. AIMS: Evaluate patients’ anticipated and actualized improvements in several domains of functioning before and after viral cure. METHODS: Pre-post study utilizing in-depth interviews with 28 patients prior to, and several months after, DAA therapy. Interviews were audio-recorded, transcribed, coded and analyzed by two qualitative experts. RESULTS: Patients had a median age of 54 years, 43% were male, 57% white, 25% had cirrhosis, and 71% were treated with sofosbuvir/ledipasvir. Pre-treatment, patients hoped for improvements in several domains including psychological, emotional, physical, social and occupational functioning. After viral cure, increased energy and less fear of transmission were pathways to better quality of life. Psychological and emotional improvements positively affected physical, social and occupational functioning. Social improvements were due to better mood and motivation, fewer symptoms, and reduced fear of stigma and transmission. Occupational benefits were linked to increased stamina, self-confidence, and less pain, anxiety, and stigma. Reduced fear of stigma had a pervasive impact on all life improvements after cure. Patient characteristics such as presence of cirrhosis or psychiatric issues influence treatment motivations. Qualitative data correspond with change in pre-post survey scores. CONCLUSIONS: Tremendous hope is placed on the ability of DAA therapy to bring about substantial improvements in life functioning after viral cure. Highly interconnected effects on quality of life worked synergistically through improved physical and psychological well-being. Stakeholders should appreciate the multi-dimensional benefits that viral eradication bestows upon individuals and society.
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- 2021
21. Metric-Based Analysis of Convergence in Complex Molecule Synthesis
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Ian Tingyung Hsu, Martin Tomanik, and Seth B. Herzon
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Stereochemistry ,Molecular Conformation ,Convergent synthesis ,010402 general chemistry ,01 natural sciences ,Coupling reaction ,chemistry.chemical_compound ,Alkaloids ,Anti-Infective Agents ,Cascade reaction ,Cyclohexenone ,Hasubanan ,Fluorenes ,010405 organic chemistry ,Quinones ,Iminium ,Stereoisomerism ,General Medicine ,General Chemistry ,0104 chemical sciences ,Propellane ,chemistry ,Polyketides ,Intramolecular force ,Diterpenes ,Sesquiterpenes - Abstract
ConspectusConvergent syntheses are characterized by the coupling of two or more synthetic intermediates of similar complexity, often late in a pathway. At its limit, a fully convergent synthesis is achieved when commercial or otherwise readily available intermediates are coupled to form the final target in a single step. Of course, in all but exceptional circumstances this level of convergence is purely hypothetical; in practice, additional steps are typically required to progress from fragment coupling to the target. Additionally, the length of the sequence required to access each target is a primary consideration in synthetic design.In this Account, we provide an overview of alkaloid, polyketide, and diterpene metabolites synthesized in our laboratory and present parameters that may be used to put the degree of convergence of each synthesis on quantitative footing. We begin with our syntheses of the antiproliferative, antimicrobial bacterial metabolite (-)-kinamycin F (1) and related dimeric structure (-)-lomaiviticin aglycon (2). These synthetic routes featured a three-step sequence to construct a complex diazocyclopentadiene found in both targets and an oxidative dimerization to unite the two halves of (-)-lomaiviticin aglycon (2). We then follow with our synthesis of the antineurodegenerative alkaloid (-)-huperzine A (3). Our route to (-)-huperzine A (3) employed a diastereoselective three-component coupling reaction, followed by the intramolecular α-arylation of a β-ketonitrile intermediate, to form the carbon skeleton of the target. We then present our syntheses of the hasubanan alkaloids (-)-hasubanonine (4), (-)-delavayine (5), (-)-runanine (6), (+)-periglaucine B (7), and (-)-acutumine (8). These alkaloids bear a 7-azatricyclo[4.3.3.01,6]dodecane (propellane) core and a highly oxidized cyclohexenone ring. The propellane structure was assembled by the addition of an aryl acetylide to a complex iminium ion, followed by intramolecular 1,4-addition. We then present our synthesis of the guanidinium alkaloid (+)-batzelladine B (9), which contains two complex polycyclic guanidine residues united by an ester linkage. This target was logically disconnected by an esterification to allow for the independent synthesis of each guanidine residue. A carefully orchestrated cascade reaction provided (+)-batzelladine B (9) in a single step following fragment coupling by esterification. We then discuss our synthesis of the diterpene fungal metabolite (+)-pleuromutilin (10). The synthesis of (+)-pleuromutilin (10) proceeded via a fragment coupling involving two neopentylic reagents and employed a nickel-catalyzed reductive cyclization reaction to close the eight-membered ring, ultimately providing access to (+)-pleuromutilin (10), (+)-12-epi-pleuromutilin (11), and (+)-12-epi-mutilin (12). Finally, we discuss our synthesis of (-)-myrocin G (13), a tricyclic pimarane diterpene that was assembled by a convergent annulation.In the final section of this Account, we present several paramaters to analyze and quantitatively assess the degree of convergence of each synthesis. These parameters include: (1) the number of steps required following the point of convergence, (2) the difference in the number of steps required to prepare each coupling partner, (3) the percentage of carbons (or, more broadly, atoms) present at the point of convergence, and (4) the complexity generated in the fragment coupling step. While not an exhaustive list, these parameters bring the strengths and weaknesses each synthetic strategy to light, emphasizing the key contributors to the degree of convergence of each route while also highlighting the nuances of these analyses.
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- 2021
22. A high-yielding solid-phase total synthesis of daptomycin using a Fmoc SPPS stable kynurenine synthon
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Scott D. Taylor, Ryan Moreira, and Jacob Wolfe
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Molecular Conformation ,Side reaction ,Peptide ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Daptomycin ,medicine ,Physical and Theoretical Chemistry ,Kynurenine ,Solid-Phase Synthesis Techniques ,chemistry.chemical_classification ,Fluorenes ,010405 organic chemistry ,Organic Chemistry ,Synthon ,Total synthesis ,Blood Proteins ,Keto–enol tautomerism ,Combinatorial chemistry ,0104 chemical sciences ,Amino acid ,chemistry ,Polar effect ,medicine.drug - Abstract
A high-yielding total synthesis of daptomycin, an important clinical antibiotic, is described. Key to the development of this synthesis was the elucidation of a Camps cyclization reaction that occurs in the solid-phase when conventionally used kynurenine (Kyn) synthons, such as Fmoc-l-Kyn(Boc,CHO)-OH and Fmoc-l-Kyn(CHO,CHO)-OH, are exposed to 20% 2-methylpiperidine (2MP)/DMF. During the synthesis of daptomycin, this side reaction was accompanied by intractable peptide decomposition, which resulted in a low yield of Dap and a 4-quinolone containing peptide. The Camps cyclization was found to occur in solution when Boc-l-Kyn(Boc,CHO)-Ot-Bu and Boc-l-Kyn(CHO,CHO)-OMe were exposed to 20% 2MP/DMF giving the corresponding 4-quinolone amino acid. In contrast, Boc-l-Kyn(CHO)-OMe was stable under these conditions, demonstrating that removing one of the electron withdrawing groups from the aforementioned building blocks prevents enolization in 2MP/DMF. Hence, a new synthesis of daptomycin was developed using Fmoc-l-Kyn(Boc)-OH, which is prepared in two steps from Fmoc-l-Trp(Boc)-OH, that proceeded with an unprecedented 22% overall yield. The simplicity and efficiency of this synthesis will facilitate the preparation of analogs of daptomycin. In addition, the elucidation of this side reaction will simplify preparation of other Kyn-containing natural products via Fmoc SPPS.
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- 2021
23. Ultrafine fluorene–pyridine oligoelectrolyte nanoparticles for supersensitive fluorescence sensing of heparin and protamine
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Wensheng Mao, Hongmei Huang, Yaqian Zhao, Huifeng Du, Youyu Zhang, Li Zhang, Kemin Wang, Xiaoxiao He, and Yi Xiao
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Pyridines ,Static Electricity ,Nanoparticle ,Sonogashira coupling ,02 engineering and technology ,Fluorene ,010402 general chemistry ,Binding, Competitive ,01 natural sciences ,Oligomer ,Catalysis ,Electrolytes ,Structure-Activity Relationship ,chemistry.chemical_compound ,Limit of Detection ,Materials Chemistry ,Humans ,Protamines ,Fluorescent Dyes ,Detection limit ,Fluorenes ,biology ,Heparin ,Optical Imaging ,Metals and Alloys ,Cationic polymerization ,General Chemistry ,021001 nanoscience & nanotechnology ,Protamine ,Combinatorial chemistry ,Fluorescence ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Spectrometry, Fluorescence ,chemistry ,MCF-7 Cells ,Ceramics and Composites ,biology.protein ,Nanoparticles ,0210 nano-technology - Abstract
A new fluorene-pyridine oligoelectrolyte (OFP) is rationally proposed and readily synthesized via a simple one-pot Sonogashira approach. Hence, an unexpectedly small cationic oligomer nanosensor (i.e. OFPNPs, ∼ 1.2 nm in diameter) was conveniently fabricated owing to the enhanced flexibility endowed by the meta-substituted pyridyl unit. Inspiringly, this facile nanoplatform with low cytotoxicity favors the ultrasensitive fluorescence assay for heparin and protamine with a detection limit (LOD, S/N = 3) as low as 1.2 ng mL-1 and 0.5 ng mL-1, respectively, involving heparin-induced aggregation of OFPNPs through electrostatic interaction or competitive rebinding of protamine to heparin.
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- 2021
24. De novo design of self-assembly hydrogels based on Fmoc-diphenylalanine providing drug release
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Chunyan Cao, Xin Yi, Huijun Zhang, Xiang Li, Yifeng Zhou, Dongfang Zhou, Tao Yi, Peng Wei, Qingyang Lv, and Lingyan Liu
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Circular dichroism ,Materials science ,Cell Survival ,Nanofibers ,Biomedical Engineering ,Nanotechnology ,Peptide ,Cell Line ,Mice ,chemistry.chemical_compound ,Animals ,Humans ,General Materials Science ,Diphenylalanine ,Cell Proliferation ,chemistry.chemical_classification ,Fluorenes ,Antibiotics, Antineoplastic ,Molecular Structure ,Hydrogels ,Dipeptides ,General Chemistry ,General Medicine ,Drug Liberation ,chemistry ,Doxorubicin ,Nanofiber ,Drug delivery ,Self-healing hydrogels ,Self-assembly ,Drug Screening Assays, Antitumor ,Peptides ,Drug carrier ,Hydrophobic and Hydrophilic Interactions - Abstract
Short peptides with self-assembled nanostructures are widely applied in the areas of drug delivery systems and biomaterials. In this article, we create a new peptide-based hydrogelator (Fmoc-FFRRVR) based on N-fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF) through an approach to improve its hydrophilicity. Compared to Fmoc-FF, Fmoc-FFRRVR prefers to form a hydrogel under mild conditions, and the gelation time is only 2 s. Fmoc-FFRRVR self-assembles into organized arrays of β-sheets in nanofibers via π-stacking of Fmoc-FF, which are supported by circular dichroism and fluorescence emission spectroscopy. Rheology results confirm that the hydrogel of Fmoc-FFRRVR is elastic, reversible and injectable. The newly discovered hydrogel not only retains some excellent performances of Fmoc-FF, but also can be used as a drug carrier for biomedical applications.
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- 2021
25. Discovery of Pamiparib (BGB-290), a Potent and Selective Poly (ADP-ribose) Polymerase (PARP) Inhibitor in Clinical Development
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Zhen Qin, Ye Liu, Yong Liu, Dan Su, Dexu Xu, Yuan Zhao, Hao Peng, Lusong Luo, Bo Ren, Fan Wang, Changxin Huo, Min Wei, Yingcai Feng, Huibin Yan, Qiu Ming, Yin Guo, Kuang Xianzhao, Wenfeng Gong, Zhiwei Wang, Hong Xu, Xuebing Sun, Yajuan Gao, Xuesong Liu, Ruipeng Qi, Lai Wang, Beibei Jiang, Changyou Zhou, Yiyuan Wu, Fenglong Yu, Yutong Zhu, Hexiang Wang, Lei Lv, Xing Wang, and Tristin Tang
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Indoles ,DNA repair ,Poly ADP ribose polymerase ,Carbazoles ,Poly(ADP-ribose) Polymerase Inhibitors ,01 natural sciences ,Mice ,Structure-Activity Relationship ,03 medical and health sciences ,Dogs ,Microsomes ,Neoplasms ,Drug Discovery ,Animals ,Humans ,Structure–activity relationship ,IC50 ,Polymerase ,Cell Proliferation ,030304 developmental biology ,chemistry.chemical_classification ,Fluorenes ,0303 health sciences ,Binding Sites ,biology ,Xenograft Model Antitumor Assays ,Rats ,0104 chemical sciences ,Isoenzymes ,Molecular Docking Simulation ,010404 medicinal & biomolecular chemistry ,Enzyme ,chemistry ,PARP inhibitor ,biology.protein ,Cancer research ,Molecular Medicine ,Female ,Poly(ADP-ribose) Polymerases ,Drug metabolism ,Half-Life - Abstract
Poly (ADP-ribose) polymerase (PARP) plays a significant role in DNA repair responses; therefore, this enzyme is targeted by PARP inhibitors in cancer therapy. Here we have developed a number of fused tetra- or pentacyclic dihydrodiazepinoindolone derivatives with excellent PARP enzymatic and cellular PARylation inhibition activities. These efforts led to the identification of pamiparib (BGB-290, 139), which displays excellent PARP-1 and PARP-2 inhibition with IC50 of 1.3 and 0.9 nM, respectively. In a cellular PARylation assay, this compound inhibits PARP activity with IC50 = 0.2 nM. Cocrystal of pamiparib shows similar binding sites with PARP with other PARP inhibitors, but pamiparib is not a P-gp substrate and shows excellent drug metabolism and pharmacokinetics (DMPK) properties with significant brain penetration (17-19%, mice). The compound is currently being investigated in phase III clinical trials as a maintenance therapy in platinum-sensitive ovarian cancer and gastric cancer.
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- 2020
26. Evidence for linkage of pfmdr1, pfcrt, and pfk13 polymorphisms to lumefantrine and mefloquine susceptibilities in a Plasmodium falciparum cross
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Thomas E. Wellems, Sean T. Windle, Jianbing Mu, Rifat S. Rahman, Juliana M. Sá, Nahla B Gadalla, Ramoncito L. Caleon, Kristin D. Lane, and Anna Liu
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0301 basic medicine ,medicine.medical_treatment ,Quantitative trait loci analysis ,Plasmodium falciparum ,030231 tropical medicine ,Protozoan Proteins ,Dihydroartemisinin ,Biology ,Lumefantrine ,Ghana ,Article ,Halofantrine ,lcsh:Infectious and parasitic diseases ,Antimalarials ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Chloroquine ,parasitic diseases ,medicine ,Humans ,Pharmacology (medical) ,lcsh:RC109-216 ,Malaria, Falciparum ,Artemisinin ,Pharmacology ,Genetics ,Fluorenes ,Mefloquine ,medicine.disease ,biology.organism_classification ,Malaria ,Artemisinin-based combination chemotherapy ,030104 developmental biology ,Infectious Diseases ,chemistry ,Ethanolamines ,Drug resistance ,Parasitology ,Multidrug Resistance-Associated Proteins ,Cambodia ,medicine.drug - Abstract
Background Lumefantrine and mefloquine are used worldwide in artemisinin-based combination therapy (ACT) of malaria. Better understanding of drug susceptibility and resistance is needed and can be obtained from studies of genetic crosses. Methods Drug response phenotypes of a cross between Plasmodium falciparum lines 803 (Cambodia) and GB4 (Ghana) were obtained as half-maximal effective concentrations (EC50s) and days to recovery (DTR) after 24 h exposure to 500 nM lumefantrine. EC50s of mefloquine, halofantrine, chloroquine, and dihydroartemisinin were also determined. Quantitative trait loci (QTL) analysis and statistical tests with candidate genes were used to identify polymorphisms associated with response phenotypes. Results Lumefantrine EC50s averaged 5.8-fold higher for the 803 than GB4 parent, and DTR results were 3–5 and 16–18 days, respectively. In 803 × GB4 progeny, outcomes of these two lumefantrine assays showed strong inverse correlation; these phenotypes also correlated strongly with mefloquine and halofantrine EC50s. By QTL analysis, lumefantrine and mefloquine phenotypes mapped to a chromosome 5 region containing codon polymorphisms N86Y and Y184F in the P. falciparum multidrug resistance 1 protein (PfMDR1). Statistical tests of candidate genes identified correlations between inheritance of PfK13 Kelch protein polymorphism C580Y (and possibly K189T) and lumefantrine and mefloquine susceptibilities. Correlations were detected between lumefantrine and chloroquine EC50s and polymorphisms N326S and I356T in the CVIET-type P. falciparum chloroquine resistance transporter (PfCRT) common to 803 and GB4. Conclusions Correlations in this study suggest common mechanisms of action in lumefantrine, mefloquine, and halofantrine responses. PfK13 as well as PfMDR1 and PfCRT polymorphisms may affect access and/or action of these arylaminoalcohol drugs at locations of hemoglobin digestion and heme metabolism. In endemic regions, pressure from use of lumefantrine or mefloquine in ACTs may drive selection of PfK13 polymorphisms along with versions of PfMDR1 and PfCRT associated with lower susceptibility to these drugs., Graphical abstract Image 1, Highlights • Two different lumefantrine response assays show inverse correlation in a P. falciparum cross. • Lumefantrine, mefloquine, and halofantrine phenotypes correlate and may have pathways of action in common. • Lumefantrine and mefloquine susceptibilities are linked to PfMDR1, PfCRT, and PfK13 polymorphisms. • Lumefantrine and mefloquine in ACTs may drive selection of PfMDR1, PfCRT, and PfK13 polymorphisms including PfK13 580Y.
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- 2020
27. Chronic Hepatitis C Virus Infection After Kidney Transplantation With or Without Direct-Acting Antivirals in a Real-Life Setting: A French Multicenter Experience
- Author
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Nicolas Bouvier, Yannick Le Meur, Cyril Garrouste, Dominique Bertrand, Johnny Sayegh, Eloi Chevallier, Matthias Büchler, Sophie Caillard, Joseph Rivalan, Antoine Thierry, Lionel Rostaing, Philippe Gatault, Charlotte Colosio, Jean-Philippe Rerolle, Service de néphrologie, dialyse, aphérèses et transplantation, CHU Grenoble-Université Joseph Fourier - Grenoble 1 (UJF), Centre Hospitalier Universitaire [Grenoble] (CHU), Laboratory of Immunology, CHRU de Tours, Tours, France, Service de néphrologie et hémodialyse [CHU de Strasbourg], CHU Strasbourg, Service de Néphrologie-Dialyse-Transplantation rénale [CHU Caen], Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Tumorothèque de Caen Basse-Normandie (TCBN), Department of Nephrology, Reims University Hospital, Reims, France, Centre Hospitalier Universitaire de Rennes (CHU Rennes), Département de Néphrologie-Dialyse-Transplantation [CHU Angers], Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM)-PRES Université Nantes Angers Le Mans (UNAM), Service de Néphrologie [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), CHRU Brest - Service de Nephrologie (CHU - BREST - Nephrologie), Centre Hospitalier Régional Universitaire de Brest (CHRU Brest), Lymphocyte B et Auto-immunité (LBAI), Université de Brest (UBO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO), Département de Néphrologie [CHU Poitiers], Centre hospitalier universitaire de Poitiers (CHU Poitiers), Service de Néphrologie [Clermont-Ferrand], CHU Clermont-Ferrand-Université d'Auvergne - Clermont-Ferrand I (UdA), Service de néphrologie et immunologie clinique [CHRU Tours] (EA4245 UT), Centre Hospitalier Régional Universitaire de Tours (CHRU Tours)-Hôpital Bretonneau-Université de Tours, Université de Brest (UBO)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)-Institut National de la Santé et de la Recherche Médicale (INSERM), Service de néphrologie et immunologie clinique [CHRU Tours], Centre Hospitalier Régional Universitaire de Tours (CHRU Tours)-Hôpital Bretonneau-Université de Tours (UT), and Université Joseph Fourier - Grenoble 1 (UJF)-CHU Grenoble
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Adult ,Male ,Ledipasvir ,medicine.medical_specialty ,Pyrrolidines ,Daclatasvir ,Sustained Virologic Response ,Sofosbuvir ,030232 urology & nephrology ,Antiviral Agents ,Gastroenterology ,Group A ,Virus ,Group B ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Humans ,Medicine ,Kidney transplantation ,Retrospective Studies ,Fluorenes ,Transplantation ,business.industry ,Imidazoles ,virus diseases ,Valine ,Hepatitis C, Chronic ,Middle Aged ,medicine.disease ,Kidney Transplantation ,3. Good health ,Treatment Outcome ,chemistry ,[SDV.IMM]Life Sciences [q-bio]/Immunology ,Benzimidazoles ,Female ,030211 gastroenterology & hepatology ,Surgery ,Carbamates ,France ,business ,Viral hepatitis ,medicine.drug - Abstract
Kidney transplant recipients (KTRs) are frequently infected with chronic hepatitis C virus (HCV), which can increase the risk of graft loss. Active HCV infections among KTRs are associated with shorter survival times. The emergence of very efficient interferon-free treatments (direct-acting antivirals [DAAs]) has revolutionized prognoses for chronic viral hepatitis. We performed a multicenter study where HCV (+)/RNA (+) KTRs were followed up and either received DAAs (group A) or not (group B) according to the transplant center. The aim was to assess, in a real-life setting, the impact of DAA therapy and to compare these results with those from HCV RNA (+) KTRs where HCV infection was not treated during the same period.This study included 66 patients from 11 centers: 44 patients (66.7%; group A) received DAAs, whereas 22 patients did not (group B); the 2 groups were comparable according to baseline data. Most patients (88.6%) received sofosbuvir, 50% received ledipasvir, and 34.7% received daclatasvir. The duration of treatments ranged from 8 to 24 weeks.HCV RNA clearance (ie, a sustained virologic response) was observed in 95.4% of treated patients. Eradication of HCV led to a significant decrease in liver enzymes (50% reduction for alanine aminotransferase [P ≤ .001] and 41% for gamma glutamyl transpeptidase [P .001]). Conversely, liver enzymes did not decrease in group B. Death occurred significantly more frequently in nontreated than treated patients (3 in group B vs none in group A, P = .003). Of the 10 treated patients with severe renal impairment before DAA therapy, 6 experienced graft loss.DAAs are very effective at treating chronic HCV and have an excellent tolerance profile.
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- 2020
28. Effective Treatment of Chronic Hepatitis C Virus Infection With Ledipasvir/Sofosbuvir in 2 Teenagers With HIV Coinfection: A Brief Report
- Author
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Agnieszka Ołdakowska, Anna Dobrzeniecka, Maria Pokorska-Śpiewak, and Magdalena Marczyńska
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Liver Cirrhosis ,Male ,Microbiology (medical) ,Ledipasvir ,medicine.medical_specialty ,Cirrhosis ,Adolescent ,Genotype ,Sustained Virologic Response ,Sofosbuvir ,Hepatitis C virus ,HIV Infections ,medicine.disease_cause ,Antiviral Agents ,Drug Administration Schedule ,Virus ,chemistry.chemical_compound ,Internal medicine ,Humans ,Medicine ,Adverse effect ,Hepatitis B virus ,Fluorenes ,business.industry ,Hepatitis C, Chronic ,medicine.disease ,Treatment Outcome ,Infectious Diseases ,chemistry ,Pediatrics, Perinatology and Child Health ,Coinfection ,Benzimidazoles ,Drug Therapy, Combination ,business ,medicine.drug - Abstract
We present the efficacy and safety of 12 weeks of therapy with a fixed dose of ledipasvir/sofosbuvir in 2 teenagers with HIV/hepatitis C virus coinfection. Patient 1 presented with compensated cirrhosis, whereas patient 2 had evidence of previous hepatitis B virus infection. Both patients achieved a sustained virologic response 12 weeks after the end of treatment. No serious adverse effects were reported.
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- 2021
29. Modeling the Formation, Degradation, and Spatiotemporal Distribution of 2-Nitrofluoranthene and 2-Nitropyrene in the Global Atmosphere
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Thomas Berkemeier, Marco Wietzoreck, Ulrich Pöschl, Gerhard Lammel, Mega Octaviani, Benjamin A. Musa Bandowe, Jake Wilson, and Cornelius Zetzsch
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Air Pollutants ,Fluorenes ,Pyrenes ,Atmosphere ,Chemistry ,General Chemistry ,010501 environmental sciences ,Combustion ,01 natural sciences ,Article ,Environmental modeling ,13. Climate action ,Adverse health effect ,Environmental chemistry ,Atmospheric chemistry ,Atmospheric pollutants ,Environmental Chemistry ,Degradation (geology) ,Polycyclic Aromatic Hydrocarbons ,2-nitropyrene ,Environmental Monitoring ,0105 earth and related environmental sciences - Abstract
Polycyclic aromatic hydrocarbons (PAHs) are common atmospheric pollutants and known to cause adverse health effects. Nitrated PAHs (NPAHs) are formed in combustion activities and by nitration of PAHs in the atmosphere and may be equally or more toxic, but their spatial and temporal distribution in the atmosphere is not well characterized. Using the global EMAC model with atmospheric chemistry and surface compartments coupled, we investigate the formation, abundance, and fate of two secondarily formed NPAHs, 2-nitrofluoranthene (2-NFLT) and 2-nitropyrene (2-NPYR). The default reactivity scenario, the model with the simplest interpretation of parameters from the literature, tends to overestimate both absolute concentrations and NPAH/PAH ratios at observational sites. Sensitivity scenarios indicate that NO2-dependent NPAH formation leads to better agreement between measured and predicted NPAH concentrations and that photodegradation is the most important loss process of 2-NFLT and 2-NPYR. The highest concentrations of 2-NFLT and 2-NPYR are found in regions with strong PAH emissions, but because of continued secondary formation from the PAH precursors, these two NPAHs are predicted to be spread across the globe.
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- 2020
30. Solution-Phase Fmoc-Based Peptide Synthesis for DNA-Encoded Chemical Libraries: Reaction Conditions, Protecting Group Strategies, and Pitfalls
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Nicholas Simmons, Martin M. Matzuk, Srinivas Chamakuri, Olivier B. C. Monty, and Damian W. Young
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chemistry.chemical_classification ,Fluorenes ,Drug discovery ,Molecular Conformation ,Peptide ,Chemistry Techniques, Synthetic ,DNA ,General Chemistry ,General Medicine ,Tripeptide ,Combinatorial chemistry ,Chemical space ,Amino acid ,Small Molecule Libraries ,Solutions ,chemistry.chemical_compound ,chemistry ,Amide ,Peptide synthesis ,Peptides ,Protecting group - Abstract
Peptide drug discovery has shown a resurgence since 2000, bringing 28 non-insulin therapeutics to the market compared to 56 since its first peptide drug, insulin, in 1923. While the main method of discovery has been biological display-phage, mRNA, and ribosome-the synthetic limitations of biological systems has restricted the depth of exploration of peptide chemical space. In contrast, DNA-encoded chemistry offers the synergy of large numbers and ribosome-independent synthetic flexibility for the fast and deeper exploration of the same space. Hence, as a bridge to building DNA-encoded chemical libraries (DECLs) of peptides, we have developed substrate-tolerant amide coupling reaction conditions for amino acid monomers, performed a coupling screen to illustrate such tolerance, developed protecting group strategies for relevant amino acids and reported the limitations thereof, developed a strategy for the coupling of α,α-disubstituted alkenyl amino acids relevant to all-hydrocarbon stapled peptide drug discovery, developed reaction conditions for the coupling of tripeptides likely to be used in DECL builds, and synthesized a fully deprotected DNA-decamer conjugate to illustrate the potency of the developed methodology for on-DNA peptide synthesis.
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- 2020
31. Efficacy of Sofosbuvir/Ledipasvir in Adolescents With Chronic Hepatitis C Genotypes 1, 3, and 4: A Real-world Study
- Author
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Silvia Riva, Pietro Vajro, Antonina Marta Cangelosi, Daniele Serranti, Erika Silvestro, Silvia Garazzino, Michele Pinon, Fabiola Di Dato, Greta Mastrangelo, Mara Cananzi, Raffaele Iorio, Federica Nuti, Emanuele Nicastro, Lorenzo D'Antiga, Pier Luigi Calvo, P. Gaio, Roberto Antonucci, Sandra Trapani, Icilio Dodi, Silvia Ricci, Elisa Bartolini, Matteo Lenge, Giuseppe Indolfi, Gabriella Nebbia, Federica Forlanini, Vania Giacomet, Serranti, Daniele, Nebbia, Gabriella, Cananzi, Mara, Nicastro, Emanuele, DI DATO, Fabiola, Nuti, Federica, Garazzino, Silvia, Silvestro, Erika, Giacomet, Vania, Forlanini, Federica, Pinon, Michele, Luigi Calvo, Pier, Riva, Silvia, Dodi, Icilio, Marta Cangelosi, Antonina, Antonucci, Roberto, Ricci, Silvia, Bartolini, Elisa, Mastrangelo, Greta, Trapani, Sandra, Lenge, Matteo, Gaio, Paola, Vajro, Pietro, Iorio, Raffaele, D'Antiga, Lorenzo, and Indolfi, Giuseppe
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hepatitis C virus ,Ledipasvir ,medicine.medical_specialty ,Adolescent ,Genotype ,Sofosbuvir ,growth ,Hepatitis C virus ,adolescents ,children ,direct-acting antivirals ,Hepacivirus ,medicine.disease_cause ,Antiviral Agents ,Benzimidazole ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Chronic hepatitis ,030225 pediatrics ,Internal medicine ,medicine ,Humans ,Prospective Studies ,Child ,Adverse effect ,Antiviral Agent ,Fluorenes ,Hepaciviru ,business.industry ,Ribavirin ,Gastroenterology ,Hepatitis C, Chronic ,Fluorene ,Prospective Studie ,Safety profile ,Treatment Outcome ,chemistry ,Pediatrics, Perinatology and Child Health ,Benzimidazoles ,Drug Therapy, Combination ,Female ,030211 gastroenterology & hepatology ,business ,Human ,medicine.drug - Abstract
OBJECTIVES: Sofosbuvir/Ledipasvir (SOF/LDV) has been approved by the European Medicine Agency (EMA) for the treatment of children and adolescents (at least 3 years of age) with chronic hepatitis C (CHC) genotype 1, 3, and 4 infection. The aim of this study was to evaluate the efficacy and safety of SOF/LDV in adolescents (12 to
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- 2020
32. Clickable azide-functionalized bromoarylaldehydes – synthesis and photophysical characterization
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Marius Friedrich, Dominik Göbel, Boris J. Nachtsheim, and Enno Lork
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Steric effects ,click-chemistry ,Organic Chemistry ,Fluorene ,Combinatorial chemistry ,Full Research Paper ,Cycloaddition ,fluorenes ,lcsh:QD241-441 ,Chemistry ,phosphorescence ,chemistry.chemical_compound ,bromoarylaldehydes ,lcsh:Organic chemistry ,chemistry ,Covalent bond ,Click chemistry ,Surface modification ,lcsh:Q ,fluorescence ,Azide ,lcsh:Science ,Phosphorescence - Abstract
Herein, we present a facile synthesis of three azide-functionalized fluorophores and their covalent attachment as triazoles in Huisgen-type cycloadditions with model alkynes. Besides two ortho- and para-bromo-substituted benzaldehydes, the azide functionalization of a fluorene-based structure will be presented. The copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) of the so-synthesized azide-functionalized bromocarbaldehydes with terminal alkynes, exhibiting different degrees of steric demand, was performed in high efficiency. Finally, we investigated the photophysical properties of the azide-functionalized arenes and their covalently linked triazole derivatives to gain deeper insight towards the effect of these covalent linkers on the emission behavior.
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- 2020
33. meta ‐Selective C−H Arylation of Fluoroarenes and Simple Arenes
- Author
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Jennifer X. Qiao, Jin-Quan Yu, Kap-Sun Yeung, Luo-Yan Liu, and William R. Ewing
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Metalation ,chemistry.chemical_element ,Protonation ,Homogeneous catalysis ,010402 general chemistry ,Ligands ,01 natural sciences ,Medicinal chemistry ,Hydrocarbons, Aromatic ,Catalysis ,Article ,Meta ,chemistry.chemical_compound ,Reactivity (chemistry) ,Norbornene ,Fluorenes ,Molecular Structure ,010405 organic chemistry ,General Chemistry ,General Medicine ,Carbon ,0104 chemical sciences ,chemistry ,Catalytic cycle ,Palladium ,Hydrogen - Abstract
Fluorine is known to promote ortho-C-H metalation. Based upon this reactivity, we employed an activated norbornene that traps the ortho-palladation intermediate and is then relayed to the meta position, leading to meta-selective C-H arylation of fluoroarenes. Deuterium experiment suggests that this meta-arylation is initiated by ortho C-H activation and the catalytic cycle is terminated by C-2 protonation. A dual-ligand system is crucial for the observed high reactivity and site selectivity. Applying this approach to simple benzene or other arenes also affords arylation products with good yield and site selectivity.
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- 2020
34. Competitive Adsorption of Polycyclic Aromatic Hydrocarbons to Carbon Nanotubes and the Impact on Bioavailability to Fathead Minnow ( Pimephales promelas )
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Cindy M. Lee, Peter van den Hurk, Erica N. Linard, and Tanju Karanfil
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Health, Toxicology and Mutagenesis ,Cyprinidae ,Biological Availability ,02 engineering and technology ,Carbon nanotube ,010501 environmental sciences ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,Adsorption ,law ,Animals ,Bile ,Environmental Chemistry ,Polycyclic Aromatic Hydrocarbons ,0105 earth and related environmental sciences ,Anthracenes ,Fluoranthene ,Fluorenes ,Anthracene ,Nanotubes, Carbon ,Phenanthrenes ,Phenanthrene ,021001 nanoscience & nanotechnology ,Bioavailability ,chemistry ,Environmental chemistry ,Pyrene ,Pimephales promelas ,0210 nano-technology - Abstract
Recent studies investigating the influence of carbon nanotubes (CNTs) on the bioavailability of organic contaminants have mostly focused on single-solute systems; however, a more likely scenario in the natural environment is a multisolute system where chemical interactions at the surface of the CNT may alter the bioavailability of these chemicals. In the present study bisolute adsorption isotherms of pairs of chemically similar polycyclic aromatic hydrocarbons (PAHs) by multiwalled carbon nanotubes (MWCNTs) were established, in conjunction with quantifying the bioavailability of the 2 competing MWCNT-adsorbed PAHs to Pimephales promelas using bile analysis by high-performance liquid chromatography with fluorescence detection. The results showed that whereas adsorption and bioavailability of chemically similar PAHs (anthracene and phenanthrene, and fluoranthene and pyrene) were the same in a single-solute system, in bisolute systems, PAHs that could better align or flex with the MWCNT surface due to morphological characteristics would outcompete the more rigid or planar PAHs. The bioavailability of individual PAHs in bisolute solutions increased by as much as 50% compared with single-solute solutions. However, the relationship between adsorption (i.e., Kd ) and concentration of PAH in the fish bile was similar in single and bisolute systems. This finding indicates that competitive interactions at the surface of MWCNTs influence bioavailability by way of altering adsorption affinity in a moderately predictable manner. Environ Toxicol Chem 2020;39:1702-1711. © 2020 SETAC.
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- 2020
35. Effects of dietary starch and lipid levels on the protein retention and growth of largemouth bass (Micropterus salmoides)
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Shixuan Zheng, Xinyu Li, Ma Xuekun, Guoyao Wu, and Kaimin Cheng
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Blood Glucose ,0301 basic medicine ,food.ingredient ,Starch ,Clinical Biochemistry ,Dietary lipid ,Micropterus ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Bass (fish) ,Animal science ,food ,Dietary Carbohydrates ,Animals ,Dry matter ,Lactic Acid ,Protein retention ,Dietary starch ,Fluorenes ,030102 biochemistry & molecular biology ,Glycogen ,biology ,Organic Chemistry ,Lipid Metabolism ,biology.organism_classification ,Dietary Fats ,Survival Rate ,030104 developmental biology ,Adipose Tissue ,Liver ,chemistry ,Bass - Abstract
Protein accretion in some fish species is affected by dietary lipids, starch and their interactions, but this aspect of nutrition is largely unknown in largemouth bass (LMB). Therefore, we designed six experimental diets with three starch levels (5%, 10%, and 15%; dry matter basis) and two lipid levels (10% and 12.5%; dry matter basis) to evaluate the effects of dietary starch and lipid levels on the protein retention, growth, feed utilization, and liver histology of LMB. There were three tanks (18 fish per tank, ~ 4.85 g per fish) per dietary treatment group and the trial lasted for 8 weeks. Fish were fed to apparent satiation twice daily. Results indicated that increasing the dietary starch level from 5 to 15% reduced (P
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- 2020
36. Highly efficient and enantioselective syntheses of (2S,3R)-3-alkyl- and alkenylglutamates from Fmoc-protected Garner’s aldehyde
- Author
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Scott D. Taylor and Ryan Moreira
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0301 basic medicine ,chemistry.chemical_classification ,Aldehydes ,Fluorenes ,030102 biochemistry & molecular biology ,Organic Chemistry ,Clinical Biochemistry ,Enantioselective synthesis ,chemistry.chemical_element ,Stereoisomerism ,Biochemistry ,Aldehyde ,03 medical and health sciences ,030104 developmental biology ,Glutamates ,chemistry ,Yield (chemistry) ,Serine ,3-O-Methylglucose ,Organic chemistry ,Lithium ,Amino Acids ,Alkyl - Abstract
A 6-step enantioselective synthesis of (2S,3R)-3-alkyl/alkenylglutamates, including the biologically significant amino acid, (2S,3R)-3-methylglutamate, protected for Fmoc SPPS, is reported. Overall yields range from 52–65%. Key to the success of these syntheses was the development of a high-yielding 2-step synthesis of Fmoc Garner’s aldehyde followed by a Horner–Wadsworth–Emmons reaction to give the corresponding Fmoc Garner’s enoate in a 94% yield. The diastereoselective 1,4-addition of lithium dialkylcuprates to the Fmoc Garner’s enoate was explored. Significant decomposition occurred when using lithium diethylcuprate and conditions previously reported for the 1,4-addition of lithium dialkylcuprates to Boc or Cbz-protected Garner’s enoate. An optimization study of this reaction resulted in a robust set of conditions that addressed the shortcomings of previously reported conditions. Under these conditions, highly diastereoselective (> 20:1 in most cases) 1,4-addition reactions of lithium dialkyl/dialkenylcuprates to the Fmoc Garner’s enoate were achieved in 76–99% yield. The resulting 1,4-addition products were easily converted into the Fmoc-(2S,3R)-3-alkyl/alkenylglutamates in two steps.
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- 2020
37. Enrichment of Semiconducting Single-Walled Carbon Nanotubes with Indigo-Fluorene-Based Copolymers and Their Use in Printed Thin-Film Transistors and Carbon Dioxide Gas Sensors
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Jianying Ouyang, Zhao Li, Jacques Lefebvre, Homin Shin, Patrick R. L. Malenfant, Arnold J. Kell, Jianfu Ding, François Lapointe, and Chang Guo
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Materials science ,Transistors, Electronic ,Polymers ,high-purity semiconducting SWCNT ,Bioengineering ,thin-film transistors ,02 engineering and technology ,Carbon nanotube ,Fluorene ,Indigo Carmine ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,law ,Amide ,Copolymer ,Instrumentation ,Fluid Flow and Transfer Processes ,chemistry.chemical_classification ,Fluorenes ,Nanotubes, Carbon ,carbon dioxide sensor ,Process Chemistry and Technology ,010401 analytical chemistry ,polymeric materials ,Polymer ,Carbon Dioxide ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Carbon dioxide sensor ,chemistry ,Chemical engineering ,Thin-film transistor ,Amine gas treating ,printed and flexible electronics ,0210 nano-technology - Abstract
High-purity semiconducting single-walled carbon nanotubes (sc-SWCNTs) are promising for portable and high-sensitivity gas sensors because of their excellent physical and electrical properties. Here, we describe the synthesis of a novel indigo-fluorene-based copolymer (PFIDBoc) that has been designed to selectively enrich sc-SWCNTs with excellent purity (>99.9%) yet contain a latent function in the form of a tert-butoxy (t-BOC)-protected amine that can be later revealed and exploited for carbon dioxide (CO₂) gas sensing. SWCNTs wrapped with the PFIDBoc polymer can be easily converted via an on-chip thermal process to reveal a vinylogous amide moiety with a secondary amine nitrogen within the indigo building block of the copolymer which is perfectly suited for CO₂ recognition. Thin-film transistors and sensors were inkjet-printed onto rigid and flexible substrates, demonstrating the versatility of enriched PFIDBoc-derived sc-SWCNT dispersions. The printed transistors exhibited a mobility up to 9 cm² V⁻¹ s⁻¹ and on/off current ratios >10⁵. We further demonstrate herein a CO₂ sensor for indoor air quality monitoring even in low humidity environments, possessing a linear response with up to ∼5.4% sensitivity and a dynamic range between 400 and 2000 ppm in air with a relative humidity of ∼ 40%.
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- 2020
38. Meeting the WHO hepatitis C virus elimination goal: Review of treatment in paediatrics
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Nathan G. Kim, Sammy Saab, Ravina Kullar, and Haydar Khalil
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Cyclopropanes ,Pediatrics ,Aminoisobutyric Acids ,Pyrrolidines ,Sustained Virologic Response ,Sofosbuvir ,Hepacivirus ,medicine.disease_cause ,chemistry.chemical_compound ,0302 clinical medicine ,030212 general & internal medicine ,Child ,Sulfonamides ,Hepatitis C ,Pibrentasvir ,Treatment Outcome ,Infectious Diseases ,Child, Preschool ,Drug Therapy, Combination ,030211 gastroenterology & hepatology ,medicine.drug ,Adult ,Ledipasvir ,medicine.medical_specialty ,Adolescent ,Genotype ,Proline ,Lactams, Macrocyclic ,Hepatitis C virus ,World Health Organization ,Antiviral Agents ,03 medical and health sciences ,Leucine ,Quinoxalines ,Virology ,Ribavirin ,medicine ,Humans ,Disease Eradication ,Fluorenes ,Hepatology ,business.industry ,Glecaprevir ,medicine.disease ,Regimen ,chemistry ,Quality of Life ,Benzimidazoles ,business - Abstract
Over 3 million paediatric patients globally and ~50 000 in the United States are estimated to be infected with HCV. Eradicating HCV in children helps prevent liver fibrosis, cirrhosis and hepatocellular carcinoma; reduces extra-hepatic manifestations of HCV; improves quality of life; and increases survival. The 2019 American Association for the Study of Liver Diseases-Infectious Diseases Society of America (AASLD-IDSA) guidelines now recommend direct-acting antiviral (DAA) treatment with an approved regimen for all children and adolescents with HCV infection aged ≥3 years. We conducted a descriptive review of the new DAA treatments for HCV infection in the paediatric population. Ledipasvir/sofosbuvir (LDV/SOF) and sofosbuvir with ribavirin (SOF/RBV) are now approved for those ≥3 years old under specific clinical scenarios; sofosbuvir/velpatasvir (SOF/VEL) is the only pangenotypic agent approved for those ≥6 years or ≥17 kg, and glecaprevir/pibrentasvir (GLE/PIB) is approved for adolescents ≥12 years old or ≥45 kg. These DAA regimens are well-tolerated and have comparable sustained virologic response rates at 12 weeks post-treatment compared to those reported in adults (close to 100%). The introduction of DAAs has significantly changed the landscape of HCV treatment in adults and children with HCV infection and has increased confidence that the 2030 World Health Organization elimination goal may be attainable. Further studies are warranted to determine the optimal treatment for children with HCV infection, including timing, regimen and duration. Additionally, with the recent paediatric approvals, long-term safety data are needed.
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- 2020
39. English hepatitis C registry data show high response rates to directly acting anti-virals, even if treatment is not completed
- Author
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David Mutimer, Yevedzo Ntuli, Ahmed M. El-Sharkawy, William Gelson, Kosh Agarwal, Ceri Townley, Daniel M. Forton, Kathryn Drysdale, Graham R. Foster, Faizel Mahomed, and Jonathan P. Bestwick
- Subjects
Cyclopropanes ,Male ,Sustained Virologic Response ,Sofosbuvir ,chemistry.chemical_compound ,0302 clinical medicine ,Medicine ,Anilides ,Pharmacology (medical) ,Registries ,030212 general & internal medicine ,Young adult ,Aged, 80 and over ,Sulfonamides ,Imidazoles ,Gastroenterology ,Valine ,Anti virals ,Hepatitis C ,Middle Aged ,Drug Combinations ,England ,Grazoprevir ,Female ,030211 gastroenterology & hepatology ,Registry data ,Uridine Monophosphate ,medicine.drug ,Adult ,Ledipasvir ,medicine.medical_specialty ,Elbasvir ,Macrocyclic Compounds ,Adolescent ,Proline ,Lactams, Macrocyclic ,Antiviral Agents ,Young Adult ,03 medical and health sciences ,Quinoxalines ,Internal medicine ,Ribavirin ,Humans ,Aged ,Benzofurans ,Fluorenes ,Hepatology ,business.industry ,medicine.disease ,digestive system diseases ,chemistry ,Benzimidazoles ,Carbamates ,business - Abstract
Background In England, choice of hepatitis C therapy is determined by national contracts that change with time, facilitating comparisons between different regimens. England has a diverse population with hepatitis C including large proportions of uncommon viral genotypes. Aim To evaluate efficacy of directly acting anti-viral treatments for hepatitis C in England using real-world data from the national treatment registry. Methods Sustained virological response (SVR) rates 12 weeks after treatment completion for patients treated between 2014 and August 2018 who attended for SVR tests were analysed in univariate subgroups using Chi-squared tests. Multivariate models were constructed with clinically relevant variables to determine predictors of SVR and evaluate the impact of treatment regimens. Results SVR data were available on 14,603 treated patients. The overall SVR rate was 95.59% [95% CI 95.25%-95.91%]. Multivariable regression modelling in patients with genotype 1 infection showed that the odds of SVR with elbasvir/grazoprevir were higher than for those treated with sofosbuvir/ledipasvir (OR 1.891, 95% CI 1.072-3.336, P = 0.028). For genotype 3, we found no significant difference between any of the treatment regimens. Patients who completed at least one third of the planned treatment duration achieved SVR rates in excess of 80%. Conclusions All of the currently licensed hepatitis C direct-acting anti-viral regimens had similar efficacy (>95%) in an unselected population. Noncompletion of planned treatment duration still resulted in over 80% SVR rates provided that more than one third of treatment was completed.
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- 2020
40. Real‐world effectiveness of glecaprevir/pibrentasvir and ledipasvir/sofosbuvir for mixed genotype hepatitis C infection: A multicenter pooled analysis in Taiwan
- Author
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Chung-Kuang Lu, Tsung-Hui Hu, Mei-Yen Chen, Chien-Hung Chen, Te-Sheng Chang, Chao-Hung Hung, Wei-Ming Chen, Jin-Hung Hu, Sheng-Nan Lu, Wen-Nan Chiu, Shui-Yi Tung, and Kuo-Liang Wei
- Subjects
Cyclopropanes ,Ledipasvir ,medicine.medical_specialty ,Aminoisobutyric Acids ,Pyrrolidines ,Genotype ,Proline ,Sustained Virologic Response ,Sofosbuvir ,Lactams, Macrocyclic ,Hepatitis C virus ,Population ,Taiwan ,Hepacivirus ,medicine.disease_cause ,Antiviral Agents ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Leucine ,Quinoxalines ,Virology ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,education ,Fluorenes ,Sulfonamides ,education.field_of_study ,Hepatology ,business.industry ,Hepatitis C ,Glecaprevir ,Hepatitis C, Chronic ,medicine.disease ,Pibrentasvir ,Discontinuation ,Infectious Diseases ,chemistry ,Benzimidazoles ,030211 gastroenterology & hepatology ,business ,medicine.drug - Abstract
Data on direct-acting antiviral agent (DAA) treatment for mixed genotype hepatitis C virus (HCV) infection are scant. This study examined the effectiveness of glecaprevir/pibrentasvir (GLE/PIB) and ledipasvir/sofosbuvir (LDV/SOF) for mixed HCV genotype infection in a real-world setting in Taiwan. We analysed the data from all patients with mixed HCV genotype infections treated with GLE/PIB or LDV/SOF from 2017 to 2019 in three Chang Gung Memorial Hospitals in Taiwan. The primary treatment outcome was sustained virologic response 12 weeks after treatment cessation (SVR12). Adverse events (AEs) were also evaluated. A total of 5190 HCV patients received DAA treatment during this time period. Among them, 116 patients (2.2%) had mixed infections of any 2 or 3 genotypes of 1a, 1b, 2, 3 and 6. Fifty-four patients received GLE/PIB and 62 received LDV/SOF. SVR12 rates for LDV/SOF vs GLE/PIB therapy were 96.6% (56/58) vs 100% (51/51) by the per-protocol analysis and 90.3% (56/62) vs 94.4% (51/54) by the evaluable population analysis. Two patients with 1b + 6 and 1b + 2 genotype infections in the LDV/SOF group had relapse. Evaluating the GLE/PIB vs LDV/SOF groups for the most common AEs revealed pruritus (16.7% vs 4.8%), abdominal discomfort (5.6% vs 8%) and fatigue (5.6% vs 4.8%). One patient with AE-related treatment discontinuation presented with liver decompensation after 4-week GLE/PIB therapy. DAA-related significant laboratory abnormalities occurred in two patients with >3× elevated bilirubin level in the GLE/PIB group. GLE/PIB and LDV/SOF are well tolerated and achieve high SVR12 rates for patients with mixed HCV genotype infection.
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- 2020
41. Modeling-Based Response-Guided Glecaprevir-Pibrentasvir Therapy for Chronic Hepatitis C to Identify Patients for Ultrashort Treatment Duration
- Author
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Harel Dahari, Michio Imamura, Evan Gorstein, Susan L. Uprichard, Kazuaki Chayama, Swikriti Dasgupta, Masataka Tsuge, Takashi Nakahara, Scott J. Cotler, Alexander Churkin, David Yardeni, Danny Barash, and Ohad Etzion
- Subjects
Cyclopropanes ,Male ,0301 basic medicine ,Pyrrolidines ,Time Factors ,Sustained Virologic Response ,Sofosbuvir ,Treatment duration ,medicine.disease_cause ,Gastroenterology ,chemistry.chemical_compound ,0302 clinical medicine ,Immunology and Allergy ,Aged, 80 and over ,Sulfonamides ,Middle Aged ,Pibrentasvir ,Drug Combinations ,Infectious Diseases ,RNA, Viral ,Drug Therapy, Combination ,Female ,030211 gastroenterology & hepatology ,medicine.drug ,Ledipasvir ,medicine.medical_specialty ,Hepatitis C virus ,Antiviral Agents ,Sofosbuvir/velpatasvir ,Drug Administration Schedule ,Major Articles and Brief Reports ,03 medical and health sciences ,Quinoxalines ,Internal medicine ,medicine ,Humans ,Elbasvir, Grazoprevir ,Aged ,Retrospective Studies ,Fluorenes ,Duration of Therapy ,Glecaprevir ,Hepatitis C, Chronic ,Models, Theoretical ,Amides ,Kinetics ,030104 developmental biology ,chemistry ,Benzimidazoles ,Carbamates - Abstract
We recently showed in a proof-of-concept study that real-time modeling-based response-guided therapy can shorten hepatitis C virus treatment duration with sofosbuvir-velpatasvir, elbasvir-grazoprevir, and sofosbuvir-ledipasvir without compromising efficacy, confirming our retrospective modeling reports in >200 patients. However, retrospective modeling of pibrentasvir-glecaprevir (P/G) treatment has yet to be evaluated. In the current study, modeling hepatitis C virus kinetics in 44 cirrhotic and noncirrhotic patients predicts that P/G treatment might have been reduced to 4, 6, and 7 weeks in 16%, 34%, and 14% of patients, respectively. These results support the further evaluation of a modeling-based response-guided therapy approach using P/G.
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- 2020
42. Polycyclic aromatic hydrocarbons (PAHs) in dry tea leaves and tea infusions in Vietnam: contamination levels and dietary risk assessment
- Author
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Truong Thi Kim, Pham Hung Viet, Nguyen Van Thanh, Lan-Anh Phan Thi, Duong Hong Anh, Nguyen Thi Lam Quynh, and Nguyen Thuy Ngoc
- Subjects
Chrysene ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Food Contamination ,010501 environmental sciences ,Risk Assessment ,complex mixtures ,01 natural sciences ,Camellia sinensis ,Chrysenes ,law.invention ,Dietary Exposure ,chemistry.chemical_compound ,Dry weight ,Geochemistry and Petrology ,law ,Benzo(a)pyrene ,Humans ,Environmental Chemistry ,media_common.cataloged_instance ,Food science ,Polycyclic Aromatic Hydrocarbons ,European union ,Essential oil ,0105 earth and related environmental sciences ,General Environmental Science ,Water Science and Technology ,media_common ,Fluoranthene ,Fluorenes ,Tea ,food and beverages ,General Medicine ,Contamination ,Plant Leaves ,Vietnam ,chemistry ,Equivalent concentration ,Pyrene ,Teas, Herbal - Abstract
The total mean ∑ $$15\overline{\text{PAHs}}$$ in samples were from 75.3 to 387.0 ng/g dry weight (d.w) and showed high value in black dry tea, followed by herbal, oolong, and green tea. The mean ∑ $$\overline{\text{PAH4}}$$ (a combination of benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) values were 54.3 ng/g, 16.4 ng/g, 14.2 ng/g, and 6.6 ng/g for black, herbal, green, and oolong teas, respectively. Concentration for benzo[a]pyrene (BaP) was from 0.4 to 35.8 ng/g, and the BaP equivalent concentration values ranged from 0.3 to 48.1 ng/g. There was only 1 black tea sample that BaP concentration exceeded the maximum level according to European Union (EU) standards. Tea samples marketed in Vietnam showed insignificant difference with the samples from other origins by same analytical method. Black teas showed high PAHs contents in dry tea samples but the released percentage of sum of PAHs from tea-to-tea infusion was lower than that in other tea type samples. The released percentages of PAH4 from tea-to-tea infusion were 40.7, 15.4, and 1.9 for green, herbal, and black tea. High temperature in black tea manufacturing processes might reduce essential oil content in tea that might effect on the PAHs partially release into the infusion. Indeed, based on EU regulations, we may conclude that tea consumers are safe in risk of exposure to PAHs obtained from teas.
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- 2020
43. SERS-Based Molecularly Imprinted Plasmonic Sensor for Highly Sensitive PAH Detection
- Author
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Verónica Montes-García, Isabel Pastoriza-Santos, María José Cordero-Ferradás, Jorge Pérez-Juste, Eduardo A. Coronado, and Alexander Castro-Grijalba
- Subjects
Materials science ,PLASMONIC SENSORS ,Metal Nanoparticles ,Nanoparticle ,Bioengineering ,Nanotechnology ,02 engineering and technology ,Spectrum Analysis, Raman ,01 natural sciences ,Molecular Imprinting ,chemistry.chemical_compound ,symbols.namesake ,Rivers ,purl.org/becyt/ford/2.10 [https] ,POLYCYCLIC AROMATIC HYDROCARBONS ,Molecule ,Seawater ,Thin film ,Instrumentation ,Fluid Flow and Transfer Processes ,Fluoranthene ,Fluorenes ,ENVIRONMENTAL ANALYSIS ,Pyrenes ,SERS ,Process Chemistry and Technology ,010401 analytical chemistry ,technology, industry, and agriculture ,Molecularly imprinted polymer ,Surface Plasmon Resonance ,021001 nanoscience & nanotechnology ,MOLECULARLY IMPRINTED POLYMERS ,0104 chemical sciences ,purl.org/becyt/ford/2 [https] ,chemistry ,symbols ,Pyrene ,Gold ,0210 nano-technology ,Raman spectroscopy ,Water Pollutants, Chemical ,Raman scattering ,HYBRID NANOSTRUCTURES - Abstract
A novel hybrid plasmonic platform based on the synergetic combination of a molecularly imprinted polymer (MIP) thin film with Au nanoparticle (NPs) assemblies, noted as Au@MIP, was developed for surface-enhanced Raman scattering (SERS) spectroscopy recognition of polycyclic aromatic hydrocarbons (PAHs). While the MIP trapped the PAH close to the Au surface, the plasmonic NPs enhanced the molecule's Raman signal. The Au@MIP fabrication comprises a two-step procedure, first, the layer-by-layer deposition of Au NPs on glass and their further coating with a uniform MIP thin film. Profilometry analysis demonstrated that the thickness and homogeneity of the MIP film could be finely tailored by tuning different parameters such as prepolymerization time or spin-coating rate. Two different PAH molecules, pyrene or fluoranthene, were used as templates for the fabrication of pyrene- or fluoranthene-based Au@MIP substrates. The use of pyrene or fluoranthene, as the template molecule to fabricate the Au@MIP thin films, enabled its ultradetection in the nM regime with a 100-fold improvement compared with the nonimprinted plasmonic sensors (Au@NIPs). The SERS data analysis allowed to estimate the binding constant of the template molecule to the MIP. The selectivity of both pyrene- and fluoranthene-based Au@MIPs was analyzed against three PAHs of different sizes. The results displayed the important role of the template molecule used for the Au@MIPs fabrication in the selectivity of the system. Finally, the practical applicability of pyrene-based Au@MIPs was shown by performing the detection of pyrene in two real samples: creek water and seawater. The design and optimization of this type of plasmonic platform will pave the way for the detection of other relevant (bio)molecules in a broad range of fields such as environmental control, food safety, or biomedicine. Fil: Castro-Grijalba, Alexander. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias de la Salud. Laboratorio de Quimica Analitica Ambiental.; Argentina. Universidad de Vigo; España Fil: Montes-García, Verónica. Universidad de Vigo; España Fil: Cordero-Ferradás, María José. Universidad de Vigo; España Fil: Coronado, Eduardo A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Pérez-Juste, Jorge. Universidad de Vigo; España Fil: Pastoriza-Santos, Isabel. Universidad de Vigo; España
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- 2020
44. Estimating Efflux Transporter-Mediated Disposition of Molecules beyond the Rule of Five (bRo5) Using Transporter Gene Knockout Rats
- Author
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Taiji Miyake
- Subjects
Cyclopropanes ,Male ,0301 basic medicine ,ATP Binding Cassette Transporter, Subfamily B ,Knockout rat ,Proline ,Abcg2 ,Metabolic Clearance Rate ,Lactams, Macrocyclic ,Administration, Oral ,Biological Availability ,Pharmaceutical Science ,Isoindoles ,Pharmacology ,Oral Mucosal Absorption ,Rats, Sprague-Dawley ,Gene Knockout Techniques ,03 medical and health sciences ,0302 clinical medicine ,Simeprevir ,In vivo ,ATP Binding Cassette Transporter, Subfamily G, Member 2 ,Animals ,P-glycoprotein ,Fluorenes ,Sulfonamides ,biology ,Chemistry ,Danoprevir ,Transporter ,General Medicine ,Isoquinolines ,Rats ,Bioavailability ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cyclosporine ,biology.protein ,ATP-Binding Cassette Transporters ,Benzimidazoles ,Efflux - Abstract
Transporter gene knockout models are a practical and widely used tool for pharmacokinetic studies in drug discovery. P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp) are major efflux transporters that control absorption and bioavailability, and are important when determining oral drug disposition. To the best of our knowledge, beyond the rule of five (bRo5) molecules launched on the market to date tend to be substrates for efflux transporters. The purpose of this study is to evaluate in vivo the impact of efflux transporters on the oral absorption process and systemic clearance using rats which lack P-gp and/or Bcrp expression. We administered five bRo5 substrates (asunaprevir, cyclosporine, danoprevir, ledipasvir, and simeprevir) intravenously or orally to wild-type and Mdr1a, Bcrp, and Mdr1a/Bcrp knockout rats, calculated the clearance, oral bioavailability, and absorption rate profile of each substrate, and compared the results. Systemic clearance of the substrates in knockout rats changed within approximately ±40% compared to wild-types, suggesting the efflux transporters do not have a significant influence on clearance in rats. On the other hand, the oral absorption of substrates in the knockout rats, especially those lacking Mdr1a, increased greatly-between 2- and 5-fold more than in wild-types. This suggests that rat efflux transporters, especially P-gp, greatly reduce the oral exposure of these substrates. Moreover, results on the absorption rate-time profile suggest that efflux transporters are constantly active during the absorption period in rats. Transporter knockout rats are a useful in vivo tool for estimating the transporter-mediated disposition of bRo5 molecules in drug discovery.
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- 2020
45. Pharmacokinetics, Safety, and Tolerability of Ledipasvir/Sofosbuvir and Sofosbuvir/Velpatasvir in Healthy Chinese Subjects
- Author
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Yanhua Ding, Kathryn Kersey, Cuiyun Li, Xiaoxue Zhu, Xiaojiao Li, Hong Zhang, and Gong Shen
- Subjects
Adult ,Male ,Ledipasvir ,China ,medicine.medical_specialty ,Sofosbuvir ,Hepatitis C virus ,Cmax ,02 engineering and technology ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Antiviral Agents ,Heterocyclic Compounds, 4 or More Rings ,Sofosbuvir/velpatasvir ,03 medical and health sciences ,chemistry.chemical_compound ,020210 optoelectronics & photonics ,0302 clinical medicine ,Internal medicine ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Humans ,Pharmacology (medical) ,Dosing ,Adverse effect ,Pharmacology ,Fluorenes ,business.industry ,Tolerability ,chemistry ,Benzimidazoles ,Female ,Carbamates ,business ,medicine.drug - Abstract
Purpose Ledipasvir/sofosbuvir and sofosbuvir/velpatasvir have been approved worldwide for the treatment of chronic hepatitis C virus (HCV) infection. Although both have been approved in China, there are currently no data on their pharmacokinetic profiles in Chinese individuals. Two studies investigated the pharmacokinetic properties, safety, and tolerability of ledipasvir/sofosbuvir and sofosbuvir/velpatasvir, respectively, in healthy Chinese subjects. Methods Two Phase I, open-label, single- and multiple-dose studies were conducted in healthy Chinese subjects. Ledipasvir/sofosbuvir (90/400 mg) or sofosbuvir/velpatasvir (400/100 mg), respectively, was administered orally once daily under fasted conditions. Subjects received a single dose (day 1) and multiple doses (days 8–17 [ledipasvir/sofosbuvir]; days 8–14 [sofosbuvir/velpatasvir]). Plasma pharmacokinetic parameters were estimated by using noncompartmental models, and safety was assessed through clinical evaluation and monitoring of adverse events. Findings Fourteen subjects were enrolled in each study (7 men, 7 women each; mean age, 30 years [ledipasvir/sofosbuvir] and 29 years [sofosbuvir/velpatasvir]). The pharmacokinetic parameters for sofosbuvir, GS-566500, GS-331007, and ledipasvir or velpatasvir were similar to historical values in non-Chinese subjects. Consistent with the t1/2 of ledipasvir relative to 24-h dosing, accumulation of 177% (AUC) and 107% (Cmax) was observed. There was no significant accumulation of velpatasvir, sofosbuvir, GS-566500, or GS-331007. Both drugs were generally well tolerated; no serious adverse events or discontinuations due to adverse events were reported. Implications Overall, ledipasvir/sofosbuvir and sofosbuvir/velpatasvir exhibited pharmacokinetic and safety profiles in healthy Chinese subjects similar to those in non-Chinese subjects in historical studies, supporting their use in the Chinese population with HCV infection. ChinaDrugTrials.org.cn identifiers: CTR20160149 (ledipasvir/sofosbuvir); CTR20160602 (sofosbuvir/velpatasvir)
- Published
- 2020
46. Ledipasvir/Sofosbuvir in Adolescents With Chronic Hepatitis C Genotype 4 With and Without Hematological Disorders: Virological Efficacy and Impact on Liver Stiffness
- Author
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Amal A. Mahmoud, Nagla H Abu-Faddan, Mohamed O. Abdel-Malek, Mohamed Eltaher Ibrahim, Abeer E Kheila, and Nahed A. Makhlouf
- Subjects
Male ,Hematological disorders ,Ledipasvir ,medicine.medical_specialty ,Adolescent ,Sofosbuvir ,Hepatitis C virus ,Hepacivirus ,medicine.disease_cause ,Antiviral Agents ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Chronic hepatitis ,Liver stiffness ,Internal medicine ,Genotype ,medicine ,Humans ,030212 general & internal medicine ,Fluorenes ,business.industry ,General Medicine ,Hepatitis C, Chronic ,Hematologic Diseases ,Treatment Outcome ,Infectious Diseases ,Liver ,chemistry ,Pediatrics, Perinatology and Child Health ,Elasticity Imaging Techniques ,LEDIPASVIR/SOFOSBUVIR ,Benzimidazoles ,Drug Therapy, Combination ,Female ,030211 gastroenterology & hepatology ,business ,medicine.drug - Abstract
Background Egypt has the highest prevalence of hepatitis C virus (HCV) infection. Anti-HCV antibodies were detectable in 3% of children in Upper Egypt. Our aim was to evaluate the efficacy of ledipasvir/sofosbuvir for chronic HCV genotype 4 in adolescents with/without hematological disorders and to determine the effect of sustained virological response (SVR) on liver stiffness. Methods Sixty-five adolescents were recruited. There were 3 patient groups: group 1, 44 treatment-naive without hematological disorders; group 2, 6 previously treated; and group 3, 15 treatment-naive with hematological disorders. All patients received sofosbuvir 400 mg/ledipasvir 90 mg per day for 12 weeks. Serum HCV RNA levels were measured before treatment, at week 12, and at 12 weeks after the end of treatment (SVR12). Liver stiffness and the aspartate aminotransferase–platelet ratio index (APRI) score were estimated at baseline and at SVR12. Results SVR12 was 100%. At SVR12, there was a significant improvement in liver stiffness in all groups. The APRI score showed significant improvements in groups 1 and 3 (P Conclusions Treatment of chronic HCV in adolescents using ledipasvir/sofosbuvir was effective, with a cure rate (at SVR12) of 100%. Significant improvement in liver stiffness was found in all groups.
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- 2020
47. Cyanomethylation of Substituted Fluorenes and Oxindoles with Alkyl Nitriles
- Author
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Gang Hong, Pradip D Nahide, and Marisa C. Kozlowski
- Subjects
Radical ,Stereoisomerism ,Fluorene ,010402 general chemistry ,Methylation ,01 natural sciences ,Biochemistry ,Article ,chemistry.chemical_compound ,Nitriles ,Molecule ,Oxindole ,Physical and Theoretical Chemistry ,Alkyl ,Quaternary carbon ,chemistry.chemical_classification ,Fluorenes ,Cyanides ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,Combinatorial chemistry ,Oxindoles ,0104 chemical sciences ,chemistry ,Functional group ,Oxidation-Reduction - Abstract
The first example of metal-free cyanomethylenation from alkyl nitriles of sp(3) C-H bonds to afford quaternary carbon centers is described. This oxidative protocol is operationally simple and features good functional group compatibility. This method provides a novel approach to highly functionalized fluorene and oxindole derivatives, which are commonly used in material and pharmaceutical areas. Control experiments provide evidence for a radical reaction process.
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- 2020
48. Ledipasvir/Sofosbuvir versus Daclatasvir/Sofosbuvir for the Treatment of Chronic Hepatitis C Genotype 4 Patients
- Author
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Ahmed Elnaggar, Lamiaa N Abdelaty, Amira A Said, and Raghda R S Hussein
- Subjects
Adult ,Liver Cirrhosis ,Male ,Ledipasvir ,medicine.medical_specialty ,Pyrrolidines ,Daclatasvir ,Drug-Related Side Effects and Adverse Reactions ,Genotype ,Sofosbuvir ,Toxicology ,Antiviral Agents ,Gastroenterology ,Random Allocation ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pegylated interferon ,Internal medicine ,medicine ,Humans ,Pharmacology (medical) ,030212 general & internal medicine ,Adverse effect ,Aged ,Pharmacology ,Fluorenes ,business.industry ,Ribavirin ,Imidazoles ,Valine ,Hepatitis C ,Hepatitis C, Chronic ,Middle Aged ,medicine.disease ,Treatment Outcome ,chemistry ,Tolerability ,Benzimidazoles ,Drug Therapy, Combination ,Egypt ,Female ,030211 gastroenterology & hepatology ,Carbamates ,business ,medicine.drug - Abstract
Background: Chronic Hepatitis C (CHC) is a common progressive healthcare challenge that leads to liver cirrhosis, liver failure, and hepatocellular carcinoma. The optimum therapy was a combination of pegylated interferon and ribavirin, which was associated with moderate response and severe side effects. Sofosbuvir revolutionized CHC treatment, especially in combination with other antiviral agents. Objective: The aim of this study was to compare and evaluate the safety and efficacy of sofosbuvir/ daclatasvir versus sofosbuvir/ledipasvir for the treatment of non-cirrhotic naïve patients with chronic Hepatitis C Virus (HCV) genotype 4 infection for 12 weeks. Method: One hundred CHC genotype 4 patients (70 females, 30 males) were recruited from the hepatology clinic at the Beni-Suef general hospital. Patients were randomly allocated into two groups that received a 12 weeks treatment of either sofosbuvir 400 mg/daclatasvir 60 mg or sofosbuvir 400 mg/ledipasvir 90 mg. The sustained virological response 12 weeks post-treatment (SVR12) (HCV RNA < Lower Limit of Quantification (LLOQ)) was determined to evaluate efficacy. The clinical laboratory tests and any reported adverse effects starting from the administration of the first dose till 30 days after the last dose were assessed to evaluate safety. The main outcome measure was the assessment of the safety, efficacy and compliance of sofosbuvir/ daclatasvir versus sofosbuvir/ledipasvir for the treatment of non-cirrhotic naïve CHC genotype 4 patients for 12 weeks. : The main outcome measure was the assessment of the safety, efficacy and compliance of sofosbuvir/ daclatasvir versus sofosbuvir/ledipasvir for the treatment of non-cirrhotic naïve CHC genotype 4 patients for 12 weeks. Results: SVR12 was achieved by 98% and 96% of patients receiving sofosbuvir plus ledipasvir and sofosbuvir plus daclatasvir, respectively. The most common adverse events reported were headache, and fatigue. No patients discontinued treatment due to adverse events. Conclusion: The findings from this study suggest that the 12 weeks treatment regimens of sofosbuvir plus daclatasvir and sofosbuvir plus ledipasvir were both efficacious and well-tolerated in patients with HCV genotype 4 infection. Impact on Practice: In this paper, we report on the most recent approaches in the treatment of Hepatitis C genotype 4 patients in Egypt. This is significant because this article focuses on comparing the efficacy and tolerability of the most commonly used antiviral drugs in Egypt.
- Published
- 2020
49. Electrostatic interactions regulate the release of small molecules from supramolecular hydrogels
- Author
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Bradley L. Nilsson, Brittany L. Abraham, Ethan S. Toriki, and N’Dea J. Tucker
- Subjects
Sustained delivery ,Drug Compounding ,Phenylalanine ,Static Electricity ,Biomedical Engineering ,Supramolecular chemistry ,Biocompatible Materials ,Nanotechnology ,macromolecular substances ,complex mixtures ,Article ,Naphthalenesulfonates ,Caffeine ,Humans ,General Materials Science ,Amino Acids ,Drug Carriers ,Fluorenes ,Chemistry ,technology, industry, and agriculture ,Cationic polymerization ,Hydrogels ,General Chemistry ,General Medicine ,Electrostatics ,Small molecule ,Molecular Weight ,Drug Liberation ,Supramolecular hydrogels ,Drug delivery ,Self-healing hydrogels ,Peptides ,Rheology - Abstract
Supramolecular hydrogels have great potential as biomaterials for sustained delivery of therapeutics. While peptide-based supramolecular hydrogels have been developed that show promise for drug delivery applications, the high cost of production has limited their widespread adoption. Low molecular weight (LMW) supramolecular hydrogels are emerging as attractive and inexpensive alternatives to peptide-based hydrogels. We recently reported novel cationic fluorenylmethyloxycarbonyl-modified phenylalanine (Fmoc-Phe) hydrogels for localized and sustained in vivo release of an anti-inflammatory agent for functional pain remediation. In an effort to further elucidate design principles to optimize these materials for delivery of a variety of molecular agents, we herein report a systematic examination of electrostatic effects on the release of cargo molecules from Fmoc-Phe derived hydrogels. Specifically, we interrogate the release of cationic, anionic, and neutral cargo molecules from a series of cationic and anionic Fmoc-Phe derived hydrogels. We observed that cargo was readily released from the hydrogels except when the cargo and hydrogel network had complementary charges, in which case the cargo was highly retained in the network. These results demonstrate that the electrostatic characteristics of both the hydrogel network and the specific cargo are critical design parameters in the formulation of LMW supramolecular hydrogel systems in the development of next-generation materials for drug delivery applications.
- Published
- 2020
50. Safety, tolerability, pharmacokinetics, and pharmacodynamics of coadministered ruxolitinib and artemether-lumefantrine in healthy adults
- Author
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Timothy N. C. Wells, Myriam El Gaaloul, Stephanie E. Reuter, M. Farouk Chughlay, Anita Kress, Paul M. Griffin, Bridget E. Barber, Hayley B. Schultz, Karen I. Barnes, Michelle J. Boyle, Stephan Chalon, Christian R. Engwerda, Rebecca Webster, Peter Tapley, Paul van Giersbergen, Nada Abla, Louise Marquart, Jörg J. Möhrle, James S. McCarthy, Chughlay, M Farouk, Barnes, Karen I, El Gaaloul, Myriam, Abla, Nada, Mohrle, Jorg J, Griffin, Paul, van Giersbergen, Paul, Reuter, Stephanie E, Schultz, Hayley B, Kress, Anita, Tapley, Peter, Webster, Rebecca A, Wells, Timothy, McCarthy, James S, Barber, Bridget E, Marquart, Louise, Boyle, Michelle J, Engwerda, Christian R, and Chalon, Stephan
- Subjects
Adult ,Male ,Ruxolitinib ,Artemether/lumefantrine ,Adolescent ,ruxolitinib ,medicine.medical_treatment ,malaria ,Dihydroartemisinin ,Clinical Therapeutics ,Pharmacology ,Placebo ,Lumefantrine ,artemether-lumefantrine ,Antimalarials ,Young Adult ,chemistry.chemical_compound ,Nitriles ,medicine ,Humans ,Single-Blind Method ,Pharmacology (medical) ,Artemether ,Malaria, Falciparum ,Fluorenes ,business.industry ,Artemether, Lumefantrine Drug Combination ,clinical trial ,Middle Aged ,Drug Combinations ,Pyrimidines ,Infectious Diseases ,phase 1 study ,Tolerability ,chemistry ,healthy volunteers ,Ethanolamines ,Pharmacodynamics ,signal transducer and activator of transcription 3 ,Pyrazoles ,Female ,business ,pharmacokinetics ,medicine.drug - Abstract
Despite repeated malaria infection, individuals living in areas where malaria is endemic remain vulnerable to reinfection. The Janus kinase (JAK1/2) inhibitor ruxolitinib could potentially disrupt the parasite-induced dysfunctional immune response when administered with antimalarial therapy. This randomized, single-blind, placebo-controlled, single-center phase 1 trial investigated the safety, tolerability, and pharmacokinetic and pharmacodynamic profile of ruxolitinib and the approved antimalarial artemether-lumefantrine in combination. Ruxolitinib pharmacodynamics were assessed by inhibition of phosphorylation of signal transducer and activator of transcription 3 (pSTAT3). Eight healthy male and female participants ages 18 to 55 years were randomized to either ruxolitinib (20 mg) (n = 6) or placebo (n = 2) administered 2 h after artemether-lumefantrine (80/480 mg) twice daily for 3 days. Mild adverse events occurred in six participants (four ruxolitinib; two placebo). The combination of artemether-lumefantrine and ruxolitinib was well tolerated, with adverse events and pharmacokinetics consistent with the known profiles of both drugs. The incidence of adverse events and artemether, dihydroartemisinin (the major active metabolite of artemether), and lumefantrine exposure were not affected by ruxolitinib coadministration. Ruxolitinib coadministration resulted in a 3-fold-greater pSTAT3 inhibition compared to placebo (geometric mean ratio = 3.01 [90% confidence interval = 2.14 to 4.24]), with a direct and predictable relationship between ruxolitinib plasma concentrations and %pSTAT3 inhibition. This study supports the investigation of the combination of artemether-lumefantrine and ruxolitinib in healthy volunteers infected with Plasmodium falciparum malaria. (This study has been registered at ClinicalTrials.gov under registration no. NCT04456634.)
- Published
- 2022
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