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Background: The role that the genetic diversity of natural Trypanosoma cruzi populations plays in response to trypanocidal treatment of chronic Chagas disease (CD) patients remains to be understood. We analysed the genetic polymorphisms of parasite bloodstream populations infecting chronic CD patients enrolled in the E1224 clinical trial.Methods: A total of 506 baseline and post-treatment follow-up samples from 188 patients were analysed. T. cruzi satellite DNA (satDNA) was amplified and sequenced using cruzi1/cruzi2 primers, and samples with TcI/III, TcII, TcIV or hybrid satDNA sequences were identified. Minicircle signatures were obtained after kinetoplast DNA amplification using 121/122 primers and restriction enzyme digestion. Genetic distances between baseline and post-treatment minicircle signatures were estimated using the Jaccard coefficient.Results: At baseline, 74.3% TcII, 17.9% hybrid and 7.8% TcI/III satDNA sequences were found, whereas at the end of follow-up the distribution was 55.2% TcII, 35.2% hybrid and 9.5% TcI/III. The placebo arm was the treatment group with the highest variation of satDNA sequences between baseline and post-treatment follow-up. Genetic distances between baseline and post-treatment minicircle signatures were similar among all treatment arms. No association between minicircle signature variability and satDNA type distribution was found.Conclusions: Genetic variability of T. cruzi bloodstream populations during post-treatment follow-up did not differ from that observed during chronic infection in the absence of treatment, suggesting that there were no selection events of E1224-resistant parasite populations. This is the first report documenting the genetic polymorphism of natural T. cruzi populations in chronic patients in the context of clinical trials with trypanocidal drugs. [ABSTRACT FROM AUTHOR]

Background: In regions with controlled vector transmission of T. cruzi, congenital transmission is the most frequent route of infection. Treatment with benznidazole (BZ) or nifurtimox (NF) for 60 days in girls and women of childbearing age showed to be effective in preventing mother to child transmission of this disease. Reports on short-course treatment (≤30 days) are scarce. Methods: Retrospective cohort study. Offspring of women with Chagas disease who received short-course treatment (≤30 days) with BZ or NF, attended between 2003 and 2022, were evaluated. Parasitemia (microhaematocrit and/or PCR) was performed at <8 months of age, and serology (ELISA and IHA) at ≥8 months to rule out congenital infection. Results: A total of 27 women receiving ≤30 days of treatment and their children were included in this study. NF was prescribed in 17/27 (63%) women, and BZ in 10/27 (37%). The mean duration of treatment was 29.2 days. None of the women experienced serious adverse events during treatment, and no laboratory abnormalities were observed. Forty infants born to these 27 treated women were included. All newborns were full term, with appropriate weight for their gestational age. No perinatal infectious diseases or complications were observed. Discussion: Several studies have shown that treatment of infected girls and women of childbearing age for 60 days is an effective practice to prevent transplacental transmission of T. cruzi. Our study demonstrated that short-duration treatment (≤30 days) is effective and beneficial in preventing transplacental transmission of Chagas disease. Author summary: Reports on short-term treatment (≤30 days) with benznidazole or nifurtimox for Chagas disease in girls and women of childbearing age are scarce. Numerous studies have previously shown that treatment of infected girls and women of childbearing age for 60 days is an effective strategy to prevent transplacental transmission of T. cruzi. However, our study provides convincing evidence that a shorter duration of treatment (≤30 days) is not only effective but also beneficial in preventing transplacental transmission of Chagas disease. Our research demonstrated unequivocally that there was no congenital infection in the offspring of the 27 women who received a 30-day treatment regimen. This was confirmed by direct testing at birth and serological confirmation after 8 months of life. [ABSTRACT FROM AUTHOR]

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have demonstrated their impact on disease-free survival (DFS) and overall survival (OS) of patients with peritoneal metastases (PM). However, prior literature lacks evidence regarding any follow-up beyond 5 years. In this study, we analyse long-term OS and DFS (more than 10 years of follow-up) of patients undergoing CRS + HIPEC in a specialized unit. We conducted a retrospective study that included only patients who underwent CRS + HIPEC from January 2001 to May 2012. Data collection was conducted by reviewing medical records and telephone calls to patients or relatives. A total of 86 patients were included. The mean PCI was nine (range 0–39) and complete cytoreduction (CC-0) was reached in 80% of patients. Postoperative complications Clavien–Dindo III-IV occurred in 27.9% of patients and the 30-day mortality rate was 2.3%. After 10 years of actual follow-up, OS was 33.7% and DFS was 31.4%. Considering the historical context in which the standard of care for patients with PM was palliation, the results obtained show that CRS + HIPEC was a valid option, with morbimortality comparable to other major abdominal surgeries and encouraging survival results, since, after 10 years of follow-up, almost one-third of patients are still alive and disease-free. [ABSTRACT FROM AUTHOR]

Transduction of producer cells during lentiviral vector (LVV) production causes the loss of 70–90% of viable particles. This process is called retro-transduction and it is a consequence of the interaction between the LVV envelope protein, VSV-G, and the LDL receptor located on the producer cell membrane, allowing lentiviral vector transduction. Avoiding retro-transduction in LVV manufacturing is crucial to improve net production and, therefore, the efficiency of the production process. Here, we describe a method for quantifying the transduction of producer cells and three different strategies that, focused on the interaction between VSV-G and the LDLR, aim to reduce retro-transduction. [ABSTRACT FROM AUTHOR]

Treatment with benznidazole for chronic Chagas disease is associated with low cure rates and substantial toxicity. We aimed to compare the parasitological efficacy and safety of 3 different benznidazole regimens in adult patients with chronic Chagas disease. The MULTIBENZ trial was an international, randomised, double-blind, phase 2b trial performed in Argentina, Brazil, Colombia, and Spain. We included participants aged 18 years and older diagnosed with Chagas disease with two different serological tests and detectable T cruzi DNA by qPCR in blood. Previously treated people, pregnant women, and people with severe cardiac forms were excluded. Participants were randomly assigned 1:1:1, using a balanced block randomisation scheme stratified by country, to receive benznidazole at three different doses: 300 mg/day for 60 days (control group), 150 mg/day for 60 days (low dose group), or 400 mg/day for 15 days (short treatment group). The primary outcome was the proportion of patients with a sustained parasitological negativity by qPCR during a follow-up period of 12 months. The primary safety outcome was the proportion of people who permanently discontinued the treatment. Both primary efficacy analysis and primary safety analysis were done in the intention-to-treat population. The trial is registered with EudraCT, 2016-003789-21, and ClinicalTrials.gov , NCT03191162 , and is completed. From April 20, 2017, to Sept 20, 2020, 245 people were enrolled, and 234 were randomly assigned: 78 to the control group, 77 to the low dose group, and 79 to the short treatment group. Sustained parasitological negativity was observed in 42 (54%) of 78 participants in the control group, 47 (61%) of 77 in the low dose group, and 46 (58%) of 79 in the short treatment group. Odds ratios were 1·41 (95% CI 0·69–2·88; p=0·34) when comparing the low dose and control groups and 1·23 (0·61–2·50; p=0·55) when comparing short treatment and control groups. 177 participants (76%) had an adverse event: 62 (79%) in the control group, 56 (73%) in the low dose group, and 59 (77%) in the short treatment group. However, discontinuations were less frequent in the short treatment group compared with the control group (2 [2%] vs 11 [14%]; OR 0·20, 95% CI 0·04–0·95; p=0·044). Participants had a similar parasitological responses. However, reducing the usual treatment from 8 weeks to 2 weeks might maintain the same response while facilitating adherence and increasing treatment coverage. These findings should be confirmed in a phase 3 clinical trial. European Community's 7th Framework Programme. [ABSTRACT FROM AUTHOR]

Background: Excessive subcutaneous adiposity in obesity is associated to positive white adipocyte tissue (WAT) differentiation (adipogenesis) and WAT expandability. Here, we hypothesized that supplementation with the insulin inhibitor and mitochondrial uncoupler, Tyrphostin (T-AG17), in vitro and in vivo inhibits adipogenesis and adipocyte hypertrophy. Methods: We used a 3T3-L1 proadipocyte cell line to identify the potential effect of T-AG17 on adipocyte differentiation and fat accumulation in vitro. We evaluated the safety of T-AG17 and its effects on physiological and molecular metabolic parameters including hormonal profile, glucose levels, adipogenesis and adipocyte hypertrophy in a diet-induced obesity model using C57BL/6 mice. Results: We found that T-AG17 is effective in preventing adipogenesis and lipid synthesis in the 3T3-L1 cell line, as evidenced by a significant decrease in oil red staining (p < 0.05). In obese C57BL/6 mice, oral administration of T-AG17 (0.175 mg/kg for 2 weeks) lead to decreased fat accumulation and WAT hypertrophy. Further, T-AG17 induced adipocyte apoptosis by activating caspase-3. In the hepatocytes of obese mice, T-AG17 promoted an increase in the size of lipid inclusions, which was accompanied by glycogen accumulation. T-AG17 did not alter serum biochemistry, including glucose, insulin, leptin, free fatty acids, creatinine, and aspartate aminotransferase. Conclusion: T-AG17 promotes adipocyte apoptosis in vivo and is an effective modulator of adipocyte differentiation and WAT hypertrophy in vitro and in vivo. Therefore, T-AG17 may be useful as a pharmacological obesity treatment. [ABSTRACT FROM AUTHOR]

BACE1 is an enzyme of scientific interest because it participates in the progression of Alzheimer’s disease. Hydroxyethylamines (HEAs) are a family of compounds which exhibit inhibitory activity toward BACE1 at a nanomolar level, favorable pharmacokinetic properties and oral bioavailability. The first step in the inhibition of BACE1 by HEAs consists of their entrance into the protease active site and the resultant conformational change in the protein, from Apo to closed form. These two conformations differ in the position of an antiparallel loop (called the flap) which covers the entrance to the catalytic site. For BACE1, closure of this flap is vital to its catalytic activity and to inhibition of the enzyme due to the new interactions thereby formed with the ligand. In the present study a dynamic energy landscape of residue-ligand interaction energies (ReLIE) measured for 112 amino acids in the BACE1 active site and its immediate vicinity during the closure of the flap induced by 8 HEAs of different inhibitory power is presented. A total of 6.272 million ReLIE calculations, based on the PM7 semiempirical method, provided a deep and quantitative view of the first step in the inhibition of the aspartyl protease. The information suggests that residues Asp93, Asp289, Thr292, Thr293, Asn294 and Arg296 are anchor points for the ligand, accounting for approximately 45% of the total protein-ligand interaction. Additionally, flap closure improved the BACE1-HEA interaction by around 25%. Furthermore, the inhibitory activity of HEAs could be related to the capacity of these ligands to form said anchor point interactions and maintain them over time: the lack of some of these anchor interactions delayed flap closure or impeded it completely, or even caused the flap to reopen. The methodology employed here could be used as a tool to evaluate future structural modifications which lead to improvements in the favorability and stability of BACE1-HEA ReLIEs, aiding in the design of better inhibitors. [ABSTRACT FROM AUTHOR]

Trypanosoma cruzi , the causative agent of Chagas disease, is divided into six Discrete Typing Units (DTUs): TcI–TcVI. We aimed to identify T. cruzi DTUs in Latin-American migrants in the Barcelona area (Spain) and to assess different molecular typing approaches for the characterization of T. cruzi genotypes. Seventy-five peripheral blood samples were analyzed by two real-time PCR methods (qPCR) based on satellite DNA (SatDNA) and kinetoplastid DNA (kDNA). The 20 samples testing positive in both methods, all belonging to Bolivian individuals, were submitted to DTU characterization using two PCR-based flowcharts: multiplex qPCR using TaqMan probes (MTq-PCR), and conventional PCR. These samples were also studied by sequencing the SatDNA and classified as type I (TcI/III), type II (TcII/IV) and type I/II hybrid (TcV/VI). Ten out of the 20 samples gave positive results in the flowcharts: TcV (5 samples), TcII/V/VI (3) and mixed infections by TcV plus TcII (1) and TcV plus TcII/VI (1). By SatDNA sequencing, we classified the 20 samples, 19 as type I/II and one as type I. The most frequent DTU identified by both flowcharts, and suggested by SatDNA sequencing in the remaining samples with low parasitic loads, TcV, is common in Bolivia and predominant in peripheral blood. The mixed infection by TcV–TcII was detected for the first time simultaneously in Bolivian migrants. PCR-based flowcharts are very useful to characterize DTUs during acute infection. SatDNA sequence analysis cannot discriminate T. cruzi populations at the level of a single DTU but it enabled us to increase the number of characterized cases in chronically infected patients. [ABSTRACT FROM AUTHOR]

Avocado oils (AO) from Hass and Fuerte varieties were extracted by supercritical CO 2 (scCO 2) at 40 and 80 °C (400 bar). The yields of the extraction ranged from 36 % to 38 % and AO extraction using scCO 2 showed a good fit to the logistic model. Physicochemical, bioactive compounds, fatty acid composition, antioxidant capacity and oxidative stability of the oil were influenced by scCO 2 extraction. Compared to commercial product extracted by cold pressing, the AO extracted with scCO 2 showed a lower total phenolic content, except for that extracted from the Fuerte variety at 80 °C, as well as higher total carotenoid and chlorophyll contents, unsaturated/saturate fatty acid ratio and antioxidant capacity in that extracted at 80 °C. However, initiation and propagation kinetic parameters, estimated at the first time using accelerated Oxitest system, showed that AO obtained by scCO 2 is more susceptible to lipid oxidation. [Display omitted] • Oil avocado extraction by supercritical CO 2 (AO-SPE) was fitted to the logistic model. • AO-SPE showed higher total carotenoid and chlorophyll content. • AO-SPE's at 80 °C and 400 bar showed higher antioxidant capacity. • Lipid oxidation of AO-SPE was performed using the Oxitest system. • AO-SPE was more susceptible to lipid oxidation as showed estimated kinetic parameters. [ABSTRACT FROM AUTHOR]

The off-diagonal regions of the one-electron density matrix (ODM) are characterized according to their contributions to the chemical bond. In particular, these regions of the ODM difference maps were used to characterize the chemical bond in various diatomic molecules. The nature of a critical point, core interaction critical point, in the off-diagonal part of ODM reveals the chemical bond type: maximum for covalent bond, minimum for closed-shell interaction, and saddle point for a charge-shift bond. [ABSTRACT FROM AUTHOR]

During the photoreaction of rhodopsin, retinal isomerizes, rotating the C11=C12 π-bond from cis to an all-trans configuration. Unprotonated (UR) or protonated (PR) retinal in the Schiff's base (SB) is related to UV and light vision. Because the UR and PR have important differences in their physicochemical reactivities, we compared the atomic and molecular properties of these molecules using DFT calculations. The C10–C11=C12–C13 dihedral angle was rotated from 0° to 180° in 45° steps, giving five conformers, and the following were calculated from them: atomic orbital (AO) contributions to the HOMO and LUMO, atomic charges, bond length, bond order, HOMO, LUMO, hardness, electronegativity, polarizability, electrostatic potential, UV-vis spectra and dipole moment (DM). Similarly, the following were analyzed: the energy profile, hybridization, pyramidalization and the hydrogen-out-of-plane (HOOP) wagging from the H11–C11=C12–H12 dihedral angle. In addition, retinal with a water H-bond (HR) in the SB was included for comparison. Interestingly, in the PR, C11 and C12 are totally the LUMO and the HOMO, respectively, and have a large electronegativity difference, which predicts an electron jump in these atoms during photoexcitation. At the same time, the PR showed a longer bond length and lower bond order, with a larger DM, lower HOMO–LUMO gap, lower hardness and higher electronegativity. In addition, the AOs of −45° and −90° conformers changed significantly, from pz to py, during the rotation concomitantly with marked hybridization, smooth pyramidalization and lower HOOP activity. Clearly, the atomic and molecular differences between the UR and PR are overwhelming, including the rotational energy profile and light absorption spectra, which indicates that light absorption of UR and PR is already determined by the retinal characteristics of the SB protonation. The HR-model compared with UR shows a lower energy barrier and a discreet bathochromic effect in the UV region. [ABSTRACT FROM AUTHOR]

Background: Foams are high porosity and low density materials. In nature, they are a common architecture. Some of their relevant technological applications include heat and sound insulation, lightweight materials, and tissue engineering scaffolds. Foams derived from natural polymers are particularly attractive for tissue culture due to their biodegradability and bio-compatibility. Here, the foaming potential of an extensive list of materials was assayed, including slabs elaborated from whole flour, the starch component only, or the protein fraction only of maize seeds. Methodology/Principal Findings: We used supercritical CO2 to produce foams from thermoplasticized maize derived materials. Polyethylene-glycol, sorbitol/glycerol, or urea/formamide were used as plasticizers. We report expansion ratios, porosities, average pore sizes, pore morphologies, and pore size distributions for these materials. High porosity foams were obtained from zein thermoplasticized with polyethylene glycol, and from starch thermoplasticized with urea/formamide. Zein foams had a higher porosity than starch foams (88% and 85%, respectively) and a narrower and more evenly distributed pore size. Starch foams exhibited a wider span of pore sizes and a larger average pore size than zein (208.84 vs. 55.43 μm2, respectively). Proof-of-concept cell culture experiments confirmed that mouse fibroblasts (NIH 3T3) and two different prostate cancer cell lines (22RV1, DU145) attached to and proliferated on zein foams. Conclusions/Significance: We conducted screening and proof-of-concept experiments on the fabrication of foams from cereal-based bioplastics. We propose that a key indicator of foamability is the strain at break of the materials to be foamed (as calculated from stress vs. strain rate curves). Zein foams exhibit attractive properties (average pore size, pore size distribution, and porosity) for cell culture applications; we were able to establish and sustain mammalian cell cultures on zein foams for extended time periods. [ABSTRACT FROM AUTHOR]

An in silico study was carried out to identify antigens for their possible collective use as vaccine candidates against diseases caused by different classes of pathogenic mycobacteria with significant clinical relevance. The genome sequences of the relevant causative agents were used in order to search for orthologous genes among them. Bioinformatics tools permitted us to identify several conserved sequences with 100% identity with no possibility of cross-reactivity to the normal flora and human proteins. Nine different proteins were characterized using the strain H37Rv as reference and taking into account their functional category, their in vivo expression and subcellular location. T and B cell epitopes were identified in the selected sequences. Theoretical prediction of population coverage was calculated for individual epitopes as well as their combinations. Several identical sequences, belonging to six proteins containing T and B cell epitopes which are not present in selected microorganisms of the normal microbial flora or in human proteins were obtained. [ABSTRACT FROM AUTHOR]

Cellular microtubules composed of α-β-tubulin heterodimers that are essential for cell shape, division, and intracellular transport are valid targets for anticancer therapy. However, not all the conserved but differentially expressed members of the β-tubulin gene superfamily have been investigated for their role in these settings. In this study, we examined roles for the hematologic isoform β-tubulin VI and functional genetic variants in the gene. β-tubulin VI was highly expressed in blood cells with a substantial interindividual variability (seven-fold variation in mRNA). We characterized DNA missense variations leading to Q43P, T274M, and R307H, and a rare nonsense variant, Y55X. Because variations in the hematologic target of microtubule-binding drugs might alter their myelosuppressive action, we tested their effect in cell lines stably expressing the different β-tubulin VI full-length variants, finding that the T274M change significantly decreased sensitivity to paclitaxel-induced tubulin polymerization. Furthermore, patients treated with paclitaxel and carrying β-tubulin VI T274M exhibited a significantly lower thrombocytopenia than wild-type homozygous patients (P = 0.031). Together, our findings define β-tubulin VI as a hematologic isotype with significant genetic variation in humans that may affect the myelosuppresive action of microtubule-binding drugs. A polymorphism found in a tubulin isoform expressed only in hemapoietic cells may contribute to the patient variation in myelosuppression that occurs after treatment with microtubule-binding drugs. [ABSTRACT FROM AUTHOR]

In this study, we scanned multiple published databases of gene expression in vivo of M. tuberculosis at different phases of infection in animals and humans, to select 38 proteins that are highly expressed in the active, latent and reactivation phases. The selected proteins were predicted for T and B epitopes. For each proteins, the regions containing T and B epitopes were selected at the same time to look for identical epitopes on M. smegmatis based on sequence alignments. Preliminary studies of humoral immunogenicity and cross-reactivity with M. tuberculosis in mice using two M. smegmatis-derived experimental vaccines were carried out, demonstrating the immunogenicity of M. smegmatis proteoliposomes and the recognition of M. tuberculosis proteins by the sera of animals immunized with this vaccine candidate. The conjunction of in silico and in vivo studies suggested the potential for future evaluation of M. smegmatis as vaccine candidate against tuberculosis using different strategies. [ABSTRACT FROM AUTHOR]

The 14α-demethylation of biosynthetic reactions is carried out exclusively by lanosta-8,24-dien-3β-ol (lanosterol). Theoretical calculations were done to determine the importance of this structure with the Hartree–Fock scheme. It was modeled on structures similar to lanosterol with variations on the endo between C8&bond;C9 (lanosta-7,24-dien-3β-ol and lanosta-6,24-dien-3β-ol) as compared with the exo between C24&bond;C25 (Lanosta-8-en-3β-ol) and the size of the side chain (27-norlanosta-8-en-3β-ol, 26,27-dinorlanosta-8-en-3β-ol, 25,26,27-trinorlanosta-8-en-3β-ol, 24,25,26,27-tetranorlanosta-8-en-3β-ol, 23,24,25,26,27-pentanorlanosta-8-en-3β-ol, 22,23,24,25,26,27-hexanorlanosta-8-en-3β-ol). Energetic, electronic, and orbital evidence was found. The theoretical data were analyzed and were found to be important for the 14α-demethylation, the presence of HOMO on the region C8&bond;C9 and C14&bond;C141, a negative charge on the outgoing methyl C141. This atomic charge varies with the size of the side chain, and with the modification of the endo and exo double bonds. The conformation of the structure of the steroid is also related to its reactivity. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]

This report deals with the biosynthetic route from lanosterol to cholesterol, particularly exploring the demethylations of which there are three, the 14α- and two 4α-demethylations. Ab-initio calculations were used to analyse the 14α- and 4α-demethylations, and the possibility of carrying out the 4α- or 4β-demethylations. The energy profile was analysed for the complete biosynthetic route, an explanation is also given as to why the 4α is preferred over the 4β-demethylation inside the body; using hardness and electrostatic potential maps. Also for the intermediates involved when the C–C bond is enlarged for the 4α- and 4β-demethylation, the hardness, the electrostatic potential maps and dipole moment were used. When C–C is enlarged of 4α, there exists an equatorial carboxyl group which shows big electrostatic potential maps on this side, which enables the receptor could be attacked by the enzyme. Therefore the reaction on this side is easier and faster than the 4β-demethylation. The dipole moment for 4α-demethylation has noticeable variation while for 4β-demethylation does not. [Copyright &y& Elsevier]