43 results on '"Fisher MF"'
Search Results
2. Likelihood ratio
- Author
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Fisher, MF, primary
- Published
- 1987
- Full Text
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3. Modular and divergent synthesis of 2, N 3-disubstituted 4-quinazolinones facilitated by regioselective N -alkylation.
- Author
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Kim KE, Comber JR, Pursel AJ, Hobby GC, McCormick CJ, Fisher MF, Marasa K, and Perry B
- Abstract
The synthesis of a biologically relevant 2-amino- N 3-alkylamido 4-quinazolinone has been accomplished in four steps from commercially available materials using design principles from both modular and divergent synthesis. N 3-Alkylation of 2-chloro-4(3 H )-quinazolinone using methyl bromoacetate, followed by C2-amination produced a suitable scaffold for introducing molecular diversity. Optimization of alkylation conditions afforded full regioselectivity, enabling exclusive access to the N -alkylated isomer. Subsequent C2-amination using piperidine, pyrrolidine, or diethylamine, followed by amide bond formation using variously substituted phenethylamines, generated fifteen unique 4-quinazolinones bearing C2-amino and N 3-alkylamido substituents. These efforts highlight the reciprocal influence of C2 and N 3 substitution on functionalization at either position, establish an effective synthetic pathway toward 2, N 3-disubstituted 4-quinazolinones, and enable preliminary bioactivity studies while providing an experiential learning opportunity for undergraduate student researchers.
- Published
- 2024
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4. Single-cell transcriptomic analyses reveal distinct immune cell contributions to epithelial barrier dysfunction in checkpoint inhibitor colitis.
- Author
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Thomas MF, Slowikowski K, Manakongtreecheep K, Sen P, Samanta N, Tantivit J, Nasrallah M, Zubiri L, Smith NP, Tirard A, Ramesh S, Arnold BY, Nieman LT, Chen JH, Eisenhaure T, Pelka K, Song Y, Xu KH, Jorgji V, Pinto CJ, Sharova T, Glasser R, Chan P, Sullivan RJ, Khalili H, Juric D, Boland GM, Dougan M, Hacohen N, Li B, Reynolds KL, and Villani AC
- Subjects
- Humans, Female, Male, Gene Expression Profiling, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes drug effects, Middle Aged, Programmed Cell Death 1 Receptor antagonists & inhibitors, Aged, Transcriptome, CTLA-4 Antigen antagonists & inhibitors, CTLA-4 Antigen genetics, CTLA-4 Antigen immunology, T-Lymphocytes, Regulatory immunology, T-Lymphocytes, Regulatory drug effects, Colon pathology, Colon immunology, Colon drug effects, Epithelial Cells immunology, Epithelial Cells drug effects, Epithelial Cells pathology, Immune Checkpoint Inhibitors adverse effects, Colitis chemically induced, Colitis immunology, Colitis genetics, Colitis pathology, Single-Cell Analysis, Intestinal Mucosa immunology, Intestinal Mucosa pathology, Intestinal Mucosa drug effects
- Abstract
Immune checkpoint inhibitor (ICI) therapy has revolutionized oncology, but treatments are limited by immune-related adverse events, including checkpoint inhibitor colitis (irColitis). Little is understood about the pathogenic mechanisms driving irColitis, which does not readily occur in model organisms, such as mice. To define molecular drivers of irColitis, we used single-cell multi-omics to profile approximately 300,000 cells from the colon mucosa and blood of 13 patients with cancer who developed irColitis (nine on anti-PD-1 or anti-CTLA-4 monotherapy and four on dual ICI therapy; most patients had skin or lung cancer), eight controls on ICI therapy and eight healthy controls. Patients with irColitis showed expanded mucosal Tregs, ITGAE
Hi CD8 tissue-resident memory T cells expressing CXCL13 and Th17 gene programs and recirculating ITGB2Hi CD8 T cells. Cytotoxic GNLYHi CD4 T cells, recirculating ITGB2Hi CD8 T cells and endothelial cells expressing hypoxia gene programs were further expanded in colitis associated with anti-PD-1/CTLA-4 therapy compared to anti-PD-1 therapy. Luminal epithelial cells in patients with irColitis expressed PCSK9, PD-L1 and interferon-induced signatures associated with apoptosis, increased cell turnover and malabsorption. Together, these data suggest roles for circulating T cells and epithelial-immune crosstalk critical to PD-1/CTLA-4-dependent tolerance and barrier function and identify potential therapeutic targets for irColitis., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)- Published
- 2024
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5. Error Fields: Personalized robotic movement training that augments one's more likely mistakes.
- Author
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Aghamohammadi NR, Bittmann MF, Klamroth-Marganska V, Riener R, Huang FC, and Patton JL
- Abstract
Control of movement is learned and uses error feedback during practice to predict actions for the next movement. We have shown that augmenting error can enhance learning, but while such findings are encouraging the methods need to be refined to accommodate a person's individual reactions to error. The current study evaluates error fields (EF) method, where the interactive robot tempers its augmentation when the error is less likely. 22 healthy participants were asked to learn moving with a visual transformation, and we enhanced the training with error fields. We found that training with error fields led to greatest reduction in error. EF training reduced error 264% more than controls who practiced without error fields, but subjects learned more slowly than our previous error magnification technique. We also found a relationship between the amount of learning and how much variability was induced by the error augmentation treatments, most likely leading to better exploration and discovery of the causes of error. These robotic training enhancements should be further explored in combination to optimally leverage error statistics to teach people how to move better., Competing Interests: Ethics Declarations Competing interests The authors declare no competing interests.
- Published
- 2023
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6. Screening p -Phenylenediamine Antioxidants, Their Transformation Products, and Industrial Chemical Additives in Crumb Rubber and Elastomeric Consumer Products.
- Author
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Zhao HN, Hu X, Gonzalez M, Rideout CA, Hobby GC, Fisher MF, McCormick CJ, Dodd MC, Kim KE, Tian Z, and Kolodziej EP
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- Liquid Chromatography-Mass Spectrometry, Tandem Mass Spectrometry, Antioxidants analysis, Antioxidants chemistry, Antioxidants classification, Phenylenediamines analysis, Phenylenediamines chemistry, Phenylenediamines classification, Rubber chemistry, Benzoquinones analysis, Benzoquinones chemistry, Benzoquinones classification
- Abstract
Recently, roadway releases of N , N '-substituted p -phenylenediamine (PPD) antioxidants and their transformation products (TPs) received significant attention due to the highly toxic 6PPD-quinone. However, the occurrence of PPDs and TPs in recycled tire rubber products remains uncharacterized. Here, we analyzed tire wear particles (TWPs), recycled rubber doormats, and turf-field crumb rubbers for seven PPD antioxidants, five PPD-quinones (PPDQs), and five other 6PPD TPs using liquid chromatography-tandem mass spectrometry. PPD antioxidants, PPDQs, and other TPs were present in all samples with chemical profiles dominated by 6PPD, DTPD, DPPD, and their corresponding PPDQs. Interestingly, the individual [PPDQ]/[PPD] and [TP]/[PPD] ratios significantly increased as total concentrations of the PPD-derived chemical decreased, indicating that TPs (including PPDQs) dominated the PPD-derived compounds with increased environmental weathering. Furthermore, we quantified 15 other industrial rubber additives (including bonding agents, vulcanization accelerators, benzotriazole and benzothiazole derivatives, and diphenylamine antioxidants), observing that PPD-derived chemical concentrations were 0.5-6 times higher than these often-studied additives. We also screened various other elastomeric consumer products, consistently detecting PPD-derived compounds in lab stoppers, sneaker soles, and rubber garden hose samples. These data emphasize that PPD antioxidants, PPDQs, and related TPs are important, previously overlooked contaminant classes in tire rubbers and elastomeric consumer products.
- Published
- 2023
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7. Suertides A-C: selective antibacterial cyclic hexapeptides from Amycolatopsis sp. MST-135876v3.
- Author
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Lacey HJ, Chen R, Vuong D, Fisher MF, Lacey E, Rutledge PJ, and Piggott AM
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- Anti-Bacterial Agents chemistry, Microbial Sensitivity Tests, Staphylococcus aureus, Amycolatopsis, Methicillin-Resistant Staphylococcus aureus
- Abstract
Amycolatopsis sp. MST-135876 was isolated from soil collected from the riverbank of El Pont de Suert, Catalonia, Spain. Cultivation of MST-135876 on a range of media led to the discovery of a previously unreported dichlorinated cyclic hexapeptide, suertide A (D-Ser, 5-Cl-D-Trp, 6-Cl-D-Trp, L-Ile, D-Val, D-Glu), featuring an unprecedented pair of adjacent 5/6-chlorotryptophan residues. Supplementing the growth medium with KBr resulted in production of the mono- and dibrominated analogues suertides B and C, respectively. Suertides A-C displayed selective activity against Bacillus subtilis (MIC 1.6 µg ml
-1 ) and Staphylococcus aureus (MIC 3.1, 6.3, and 12.5 µg ml-1 , respectively), while suertides A and B showed appreciable activity against methicillin-resistant S. aureus (MIC 1.6 and 6.3 µg ml-1 , respectively)., (© 2022. The Author(s).)- Published
- 2022
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8. Crystal structure of Arabidopsis thaliana HPPK/DHPS, a bifunctional enzyme and target of the herbicide asulam.
- Author
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Vadlamani G, Sukhoverkov KV, Haywood J, Breese KJ, Fisher MF, Stubbs KA, Bond CS, and Mylne JS
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- Anti-Bacterial Agents chemistry, Anti-Bacterial Agents metabolism, Carbamates, Dihydropteroate Synthase chemistry, Dihydropteroate Synthase genetics, Dihydropteroate Synthase metabolism, Sulfonamides chemistry, Arabidopsis genetics, Arabidopsis metabolism, Herbicides pharmacology
- Abstract
Herbicides are vital for modern agriculture, but their utility is threatened by genetic or metabolic resistance in weeds, as well as regulatory barriers. Of the known herbicide modes of action, 7,8-dihydropterin synthase (DHPS), which is involved in folate biosynthesis, is targeted by just one commercial herbicide, asulam. A mimic of the substrate para-aminobenzoic acid, asulam is chemically similar to sulfonamide antibiotics, and although it is still in widespread use, asulam has faced regulatory scrutiny. With an entire mode of action represented by just one commercial agrochemical, we sought to improve the understanding of its plant target. Here we solve a 2.3 Å resolution crystal structure for Arabidopsis thaliana DHPS that is conjoined to 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase (HPPK), and we reveal a strong structural conservation with bacterial counterparts at the sulfonamide-binding pocket of DHPS. We demonstrate that asulam and the antibiotic sulfamethoxazole have herbicidal as well as antibacterial activity, and we explore the structural basis of their potency by modeling these compounds in mitochondrial HPPK/DHPS. Our findings suggest limited opportunity for the rational design of plant selectivity from asulam and indicate that pharmacokinetic or delivery differences between plants and microbes might be the best ways to safeguard this mode of action., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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9. Disrespect and abuse, mistreatment and obstetric violence: a challenge for epidemiology and public health in Brazil.
- Author
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Leite TH, Marques ES, Esteves-Pereira AP, Nucci MF, Portella Y, and Leal MDC
- Subjects
- Attitude of Health Personnel, Brazil epidemiology, Delivery, Obstetric, Female, Humans, Infant, Newborn, Parturition, Pregnancy, Professional-Patient Relations, Public Health, Violence, Maternal Health Services
- Abstract
Studies on disrespect and abuse/mistreatment/obstetric violence during pregnancy, childbirth and puerperium have increased in recent decades. However, researchers interested in the subject face many theoretical and methodological difficulties. In this sense, this study aims to discuss and reflect on how issues related to definition and terminology, measurement, and public policies in Brazil have hindered research on this topic and the mitigation of these acts. The first problem addressed was the lack of consensus regarding the terminology and definition of this construct. This situation causes a cascading effect, impacting the use of non-validated measurement instruments and, consequently, a lack of accuracy and comparability between studies. Another issue mentioned is the lack of studies exploring the consequences of these acts on women's and newborn's health, which is one of the main gaps on the subject today. The absence of causal studies affects health decision-making, impairing the elaboration of specific public policies.
- Published
- 2022
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10. Structural Characterization of the PawL-Derived Peptide Family, an Ancient Subfamily of Orbitides.
- Author
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Payne CD, Fisher MF, Mylne JS, and Rosengren KJ
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- Anti-Infective Agents pharmacology, Magnetic Resonance Spectroscopy, Peptides, Cyclic chemical synthesis, Peptides, Cyclic isolation & purification, Peptides, Cyclic pharmacology, Solid-Phase Synthesis Techniques, Peptides, Cyclic chemistry
- Abstract
Plants are an excellent source of bioactive peptides, often with disulfide bonds and/or a cyclic backbone. While focus has predominantly been directed at disulfide-rich peptides, a large family of small, cyclic plant peptides lacking disulfide bonds, known as orbitides, has been relatively ignored. A recently discovered subfamily of orbitides is the PawL-derived peptides (PLPs), produced during the maturation of precursors for seed storage albumins. Although their evolutionary origins have been dated, in-depth exploration of the family's structural characteristics and potential bioactivities remains to be conducted. Here we present an extensive and systematic characterization of the PLP family. Nine PLPs were chosen and prepared by solid phase peptide synthesis. Their structural features were studied using solution NMR spectroscopy, and seven were found to possess regions of backbone order. Ordered regions consist of β-turns, with some PLPs adopting two well-defined β-turns within sequences as short as seven residues, which are largely the result of side chain interactions. Our data highlight that the sequence diversity within this family results in equally diverse structures. None of these nine PLPs showed antibacterial or antifungal activity.
- Published
- 2021
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11. Solution NMR and racemic crystallography provide insights into a novel structural class of cyclic plant peptides.
- Author
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Payne CD, Vadlamani G, Hajiaghaalipour F, Muhammad T, Fisher MF, Andersson HS, Göransson U, Clark RJ, Bond CS, Mylne JS, and Rosengren KJ
- Abstract
Head-to-tail cyclic and disulfide-rich peptides are natural products with applications in drug design. Among these are the PawS-Derived Peptides (PDPs) produced in seeds of the daisy plant family. PDP-23 is a unique member of this class in that it is twice the typical size and adopts two β-hairpins separated by a hinge region. The β-hairpins, both stabilised by a single disulfide bond, fold together into a V-shaped tertiary structure creating a hydrophobic core. In water two PDP-23 molecules merge their hydrophobic cores to form a square prism quaternary structure. Here, we synthesised PDP-23 and its enantiomer comprising d-amino acids and achiral glycine, which allowed us to confirm these solution NMR structural data by racemic crystallography. Furthermore, we discovered the related PDP-24. NMR analysis showed that PDP-24 does not form a dimeric structure and it has poor water solubility, but in less polar solvents adopts near identical secondary and tertiary structure to PDP-23. The natural role of these peptides in plants remains enigmatic, as we did not observe any antimicrobial or insecticidal activity. However, the plasticity of these larger PDPs and their ability to change structure under different conditions make them appealing peptide drug scaffolds., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)
- Published
- 2021
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12. Evaluating the aortic stenosis phenotype before and after the effect of homogentisic acid lowering therapy: Analysis of a large cohort of eighty-one alkaptonuria patients.
- Author
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Ranganath LR, Heseltine T, Khedr M, and Fisher MF
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- Adult, Aged, Cohort Studies, Female, Humans, Male, Middle Aged, Severity of Illness Index, Alkaptonuria complications, Alkaptonuria drug therapy, Aortic Valve Stenosis physiopathology, Cyclohexanones therapeutic use, Enzyme Inhibitors therapeutic use, Nitrobenzoates therapeutic use, Phenotype
- Abstract
Aims: A large alkaptonuria (AKU) cohort was studied to better characterise the poorly understood phenotype of aortic stenosis of rare disease AKU., Methods and Results: Eighty-one patients attended the National Alkaptonuria Centre (NAC) between 2007 and 2020. Nine only attended once. Fifty-one attended more than once and received nitisinone 2 mg daily. Twenty-one attended at least twice without receiving nitisinone. Assessments included questionnaire analysis, standard transthoracic echocardiography, as well as photographs of ochronotic pigment in eyes and ears at baseline when 2 mg nitisinone was commenced, and yearly thereafter. Blood and urine samples were collected for chemical measurement. The prevalence of aortic stenosis and aortic valve replacement were 22.2 and 6.2% in the current group. Aortic maximum velocity (Vmax) was directly related to varying degrees to age (R = 0.58, p < 0.001), systolic blood pressure (R = 0.32, p < 0.05), serum homogentisic acid (sHGA) (R = 0.28, p < 0.05), ochronosis scores (R = 0.72, p < 0.001), and alkaptonuria severity score index (AKUSSI) (R = 0.58, p < 0.001) on linear regression analysis. Age and ochronosis scores were significantly related to Vmax on multiple regression analysis (p < 0.005). Nitisinone decreased sHGA, 24-h urine HGA (uHGA
24) , ochronosis scores and AKUSSI significantly at all visits post-nitisinone. Nitisinone decreased Vmax change scores at final visit comparison, with a similar pattern at earlier visits., Conclusion: Aortic valve disease is highly prevalent in this NAC cohort, and strongly associated with ochronosis and disease severity. Nitisinone decreases ochronosis and had a similar significant effect on Vmax., (Copyright © 2021 Elsevier Inc. All rights reserved.)- Published
- 2021
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13. A chameleonic macrocyclic peptide with drug delivery applications.
- Author
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Payne CD, Franke B, Fisher MF, Hajiaghaalipour F, McAleese CE, Song A, Eliasson C, Zhang J, Jayasena AS, Vadlamani G, Clark RJ, Minchin RF, Mylne JS, and Rosengren KJ
- Abstract
Head-to-tail cyclized peptides are intriguing natural products with unusual properties. The PawS-Derived Peptides (PDPs) are ribosomally synthesized as part of precursors for seed storage albumins in species of the daisy family, and are post-translationally excised and cyclized during proteolytic processing. Here we report a PDP twice the typical size and with two disulfide bonds, identified from seeds of Zinnia elegans . In water, synthetic PDP-23 forms a unique dimeric structure in which two monomers containing two β-hairpins cross-clasp and enclose a hydrophobic core, creating a square prism. This dimer can be split by addition of micelles or organic solvent and in monomeric form PDP-23 adopts open or closed V-shapes, exposing different levels of hydrophobicity dependent on conditions. This chameleonic character is unusual for disulfide-rich peptides and engenders PDP-23 with potential for cell delivery and accessing novel targets. We demonstrate this by conjugating a rhodamine dye to PDP-23, creating a stable, cell-penetrating inhibitor of the P-glycoprotein drug efflux pump., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2021
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14. Defining the Familial Fold of the Vicilin-Buried Peptide Family.
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Payne CD, Vadlamani G, Fisher MF, Zhang J, Clark RJ, Mylne JS, and Rosengren KJ
- Subjects
- Amino Acid Sequence, Disulfides chemistry, Helix-Loop-Helix Motifs, Magnetic Resonance Spectroscopy, Models, Molecular, Molecular Structure, Peptides chemical synthesis, Peptides chemistry, Peptides pharmacology, Protein Conformation, alpha-Helical, Seed Storage Proteins chemical synthesis, Seed Storage Proteins pharmacology, Trypsin Inhibitors pharmacology, Protein Folding, Seed Storage Proteins chemistry
- Abstract
Plants and their seeds have been shown to be a rich source of cystine-stabilized peptides. Recently a new family of plant seed peptides whose sequences are buried within precursors for seed storage vicilins was identified. Members of this Vicilin-Buried Peptide (VBP) family are found in distantly related plant species including the monocot date palm, as well as dicotyledonous species like pumpkin and sesame. Genetic evidence for their widespread occurrence indicates that they are of ancient origin. Limited structural studies have been conducted on VBP family members, but two members have been shown to adopt a helical hairpin fold. We present an extensive characterization of VBPs using solution NMR spectroscopy, to better understand their structural features. Four peptides were produced by solid phase peptide synthesis and shown to favor a helix-loop-helix hairpin fold, as a result of the I-IV/II-III ladderlike connectivity of their disulfide bonds. Interhelical interactions, including hydrophobic contacts and salt bridges, are critical for the fold stability and control the angle at which the antiparallel α-helices interface. Activities reported for VBPs include trypsin inhibitory activity and inhibition of ribosomal function; however, their diverse structural features despite a common fold suggest that additional bioactivities yet to be revealed are likely.
- Published
- 2020
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15. The genetic origin of evolidine, the first cyclopeptide discovered in plants, and related orbitides.
- Author
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Fisher MF, Payne CD, Chetty T, Crayn D, Berkowitz O, Whelan J, Rosengren KJ, and Mylne JS
- Subjects
- Amino Acid Sequence, Chromatography, High Pressure Liquid, Nuclear Magnetic Resonance, Biomolecular, Peptides, Cyclic chemistry, Peptides, Cyclic metabolism, Plant Leaves metabolism, Rutaceae genetics, Sequence Alignment, Tandem Mass Spectrometry, Peptides, Cyclic genetics, Rutaceae metabolism
- Abstract
Cyclic peptides are reported to have antibacterial, antifungal, and other bioactivities. Orbitides are a class of cyclic peptides that are small, head-to-tail cyclized, composed of proteinogenic amino acids and lack disulfide bonds; they are also known in several genera of the plant family Rutaceae. Melicope xanthoxyloides is the Australian rain forest tree of the Rutaceae family in which evolidine, the first plant cyclic peptide, was discovered. Evolidine (cyclo-SFLPVNL) has subsequently been all but forgotten in the academic literature, so to redress this we used tandem MS and de novo transcriptomics to rediscover evolidine and decipher its biosynthetic origin from a short precursor just 48 residues in length. We also identified another six M. xanthoxyloides orbitides using the same techniques. These peptides have atypically diverse C termini consisting of residues not recognized by either of the known proteases plants use to macrocyclize peptides, suggesting new cyclizing enzymes await discovery. We examined the structure of two of the novel orbitides by NMR, finding one had a definable structure, whereas the other did not. Mining RNA-seq and whole genome sequencing data from other species of the Rutaceae family revealed that a large and diverse family of peptides is encoded by similar sequences across the family and demonstrates how powerful de novo transcriptomics can be at accelerating the discovery of new peptide families., Competing Interests: Conflict of interest—The authors declare that they have no conflicts of interest with the contents of this article., (© 2020 Fisher et al.)
- Published
- 2020
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16. Three-dimensional culture models to study drug resistance in breast cancer.
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Fisher MF and Rao SS
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- Animals, Biocompatible Materials chemistry, Cell Culture Techniques instrumentation, Cell Culture Techniques methods, Drug Screening Assays, Antitumor instrumentation, Female, Humans, Lab-On-A-Chip Devices, Spheroids, Cellular cytology, Spheroids, Cellular drug effects, Tissue Scaffolds chemistry, Tumor Cells, Cultured, Tumor Microenvironment drug effects, Antineoplastic Agents pharmacology, Breast Neoplasms drug therapy, Drug Resistance, Neoplasm, Drug Screening Assays, Antitumor methods
- Abstract
Despite recent advances in breast cancer treatment, drug resistance frequently presents as a challenge, contributing to a higher risk of relapse and decreased overall survival rate. It is now generally recognized that the extracellular matrix and cellular heterogeneity of the tumor microenvironment influences the cancer cells' ultimate fate. Therefore, strategies employed to examine mechanisms of drug resistance must take microenvironmental influences, as well as genetic mutations, into account. This review discusses three-dimensional (3D) in vitro model systems which incorporate microenvironmental influences to study mechanisms of drug resistance in breast cancer. These bioengineered models include spheroid-based models, biomaterial-based models such as polymeric scaffolds and hydrogels, and microfluidic chip-based models. The advantages of these model systems over traditionally studied two-dimensional tissue culture polystyrene are examined. Additionally, the applicability of such 3D models for studying the impact of tumor microenvironment signals on drug response and/or resistance is discussed. Finally, the potential of such models for use in the development of strategies to combat drug resistance and determine the most promising treatment regimen is explored., (© 2020 Wiley Periodicals, Inc.)
- Published
- 2020
- Full Text
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17. Cyclic Peptides in Seed of Annona muricata Are Ribosomally Synthesized.
- Author
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Fisher MF, Zhang J, Berkowitz O, Whelan J, and Mylne JS
- Subjects
- Amino Acid Sequence, Anti-Inflammatory Agents analysis, Molecular Structure, Peptides, Cyclic chemistry, Plant Leaves chemistry, Plants, Medicinal, Annona chemistry, Anti-Inflammatory Agents chemistry, Peptides, Cyclic chemical synthesis, Plant Extracts chemistry
- Abstract
Small, cyclic peptides are reported to have many bioactivities. In bacteria and fungi, they can be made by nonribosomal peptide synthetases, but in plants they are exclusively ribosomal. Cyclic peptides from the Annona genus possess cytotoxic and anti-inflammatory activities, but their biosynthesis is unknown. The medicinal soursop plant, Annona muricata , contains annomuricatins A (cyclo-PGFVSA) and B (cyclo-PNAWLGT). Here, using de novo transcriptomics and tandem mass spectrometry, we identify a suite of short transcripts for precursor proteins for 10 validated annomuricatins, 9 of which are novel. In their precursors, annomuricatins are preceded by an absolutely conserved Glu and each peptide sequence has a conserved proto-C-terminal Pro, revealing parallels with the segetalin orbitides from the seed of Vaccaria hispanica , which are processed through ligation by a prolyl oligopeptidase in a transpeptidation reaction.
- Published
- 2020
- Full Text
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18. Sequencing Orbitides by Acid-Mediated Ring Cleavage Followed by Tandem Mass Spectrometry.
- Author
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Fisher MF and Mylne JS
- Subjects
- Acids chemistry, Annona chemistry, Cyclotides chemistry, Hydrolysis, Peptides chemistry, Peptides, Cyclic chemistry, Plant Proteins analysis, Plant Proteins chemistry, Reproducibility of Results, Temperature, Cyclotides analysis, Peptides analysis, Peptides, Cyclic analysis, Sequence Analysis, Protein methods, Tandem Mass Spectrometry methods
- Abstract
Homodetic cyclic peptides have aroused interest because of their pharmacological potential. Sequencing cyclic peptides is difficult-Edman degradation is not possible as there is no N-terminus, NMR requires quantities that are hard to gather from native samples, and tandem mass spectrometry data are difficult to interpret due to the peptide ring opening at multiple points. Sequencing can be simplified by cleaving the peptide ring at a specific peptide bond. Partial acid hydrolysis is a possible solution, but to date sequencing by this method has only been demonstrated for linear peptides and cyclotides, which are larger cyclic peptides (∼30 amino acids) with three disulfide bonds. This study tests whether partial acid hydrolysis could be used to aid sequencing of Cys-less cyclic peptides with fewer than ten amino acid residues. We show that, with the right combination of temperature and acid, ring cleavage occurs and offers relatively simple MS/MS spectra amenable to sequencing. We describe how this method was used in our recent study in which we sequenced annomuricatin D (cyclo-GHSIFPPIP) from seeds of the soursop, Annona muricata . We found that orbitides can be linearized for MS/MS sequencing by incubation with 1.2 M HCl at 90 °C for 15-20 min. This fast, economical sequencing method will be useful to those studying small cyclic peptides lacking disulfide bonds, which are commonly found in many organisms, especially plants.
- Published
- 2019
- Full Text
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19. From the search for diagnosis to treatment uncertainties: challenges of care for rare genetic diseases in Brazil.
- Author
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Iriart JAB, Nucci MF, Muniz TP, Viana GB, Aureliano WA, and Gibbon S
- Subjects
- Brazil, Caregivers statistics & numerical data, Cities, Genetic Diseases, Inborn therapy, Health Personnel statistics & numerical data, Health Services Accessibility, Humans, Interviews as Topic, Patient Compliance, Rare Diseases genetics, Rare Diseases therapy, Genetic Diseases, Inborn diagnosis, Public Health, Rare Diseases diagnosis
- Abstract
Rare genetic diseases are an important public health problem, but they are still little studied in Collective Health. This article aims to analyze the 'therapeutic itineraries' of patients in search of a diagnosis and treatment for rare genetic diseases in the cities of Rio de Janeiro, Salvador and Porto Alegre. It focuses on the material challenges, emotional and structural problems faced in these trajectories. Semi-structured interviews were conducted with patients/caregivers and health professionals in the context of public health medical genetics. Our findings suggest that the experience of the rare genetic disease is aggravated by practical, inter-relational and bureaucratic/institutional problems. The reality of long and circuitous journeys to obtain a diagnosis, non-geneticists' lack of knowledge about rare diseases, difficulties in transportation and access to specialists, diagnostic and complementary examinations, and access to high-cost medicines and food supplies were common challenges in all the narratives examined in the three Brazilian cities. In addition, adherence to care provided by medical genetics requires action and strategies that depend on arrangements involving family members, physicians, patient associations, and the state.
- Published
- 2019
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20. An Orbitide from Ratibida columnifera Seed Containing 16 Amino Acid Residues.
- Author
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Fisher MF, Payne CD, Rosengren KJ, and Mylne JS
- Subjects
- Amino Acid Sequence, Mass Spectrometry, Nuclear Magnetic Resonance, Biomolecular, Peptides, Cyclic chemistry, Protein Conformation, Amino Acids analysis, Peptides, Cyclic isolation & purification, Ratibida embryology, Seeds chemistry
- Abstract
Cyclic peptides are abundant in plants and have attracted interest due to their bioactivity and potential as drug scaffolds. Orbitides are head-to-tail cyclic peptides that are ribosomally synthesized, post-translationally modified, and lack disulfide bonds. All known orbitides contain 5-12 amino acid residues. Here we describe PLP-53, a novel orbitide from the seed of Ratibida columnifera . PLP-53 consists of 16 amino acids, four residues larger than any known orbitide. NMR structural studies showed that, compared to previously characterized orbitides, PLP-53 is more flexible and, under the studied conditions, did not adopt a single ordered conformation based on analysis of NOEs and chemical shifts.
- Published
- 2019
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21. Facilitators and Barriers to the Implementation of the HPV VACs (Vaccinate Adolescents Against Cancers) Program: A Consolidated Framework for Implementation Research Analysis.
- Author
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Escoffery C, Riehman K, Watson L, Priess AS, Borne MF, Halpin SN, Rhiness C, Wiggins E, and Kegler MC
- Subjects
- Adolescent, Attitude of Health Personnel, Female, Health Knowledge, Attitudes, Practice, Health Personnel, Humans, Male, Primary Health Care, Public Health Administration, United States, Papillomavirus Infections prevention & control, Papillomavirus Vaccines immunology, Vaccination
- Abstract
Purpose and Objectives: The human papillomavirus (HPV) vaccine is an effective but underused method for preventing multiple cancers, particularly cervical cancer. Although interventions have successfully targeted barriers to HPV vaccine uptake in various clinical settings, few studies have explored their implementation. Our study examines the delivery of the HPV VACs (Vaccinate Adolescents Against Cancer) Program and elicits information on barriers and facilitators to implementation., Intervention Approach: The VACs Program pilot was a multilevel, evidence-based intervention conducted by the American Cancer Society in 30 federally qualified health centers (FQHCs) in the United States., Evaluation Methods: We conducted in-depth interviews (N = 32) by telephone with representatives of 9 FQHC partners. We structured the interview guides on Consolidated Framework for Implementation Research (CFIR) domains. We asked about project start-up activities, implementation strategy selection, policy- and practice-level changes, staffing structure, challenges, and key factors leading to project success. At least 2 researchers coded each interview transcript verbatim., Results: Participants most frequently identified the electronic health record system, training and education, concrete tools and resources, and provider champions as facilitators to implementing HPV VACs. Limited staff resources, challenges of electronic health records, issues with state immunization registries, patient misinformation about vaccines and vaccine stigma, cultural/language barriers, competing priorities, levels of funding, staff buy-in, training needs, and low health literacy were identified as barriers., Implications for Public Health: Providing appropriate training for FQHC staff members and providers along with technical assistance and facilitation tools were critical for increasing provider confidence in recommending HPV vaccine. Addressing capacity-building and implementation barriers in FQHCs can increase effective implementation of evidence-based interventions to increase HPV vaccination uptake and reduce the burden of future cancers.
- Published
- 2019
- Full Text
- View/download PDF
22. PULSE-I - Is rePetitive Upper Limb SEnsory stimulation early after stroke feasible and acceptable? A stratified single-blinded randomised controlled feasibility study.
- Author
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Chatterjee K, Stockley RC, Lane S, Watkins C, Cottrell K, Ankers B, Davies S, Morris MF, Fallon N, and Nurmikko T
- Subjects
- Adult, Aged, Aged, 80 and over, Disability Evaluation, England, Feasibility Studies, Female, Humans, Male, Middle Aged, Recovery of Function, Single-Blind Method, Stroke diagnosis, Stroke physiopathology, Time Factors, Treatment Outcome, Electric Stimulation Therapy, Motor Activity, Stroke therapy, Stroke Rehabilitation methods, Upper Extremity innervation
- Abstract
Background: Reduction in sensorimotor function of the upper limb is a common and persistent impairment after stroke, and less than half of stroke survivors recover even basic function of the upper limb after a year. Previous work in stroke has shown that repetitive sensory stimulation (RSS) of the upper limb may benefit motor function. As yet, there have been no investigations of RSS in the early-acute period despite this being the time window during which the neuroplastic processes underpinning sensorimotor recovery are likely to occur., Methods: A single-blinded, stratified, randomised controlled feasibility study was undertaken at two NHS acute trusts to determine the recruitment rate, intervention adherence, and safety and acceptability of an RSS intervention in the early period after stroke. Participants were recruited within 2 weeks of index stroke. Stratified on arm function, they were randomised to receive either 45 min of daily RSS and usual care or usual care alone (UC) for 2 weeks. Changes from baseline on the primary outcome of the Action Research Arm Test (ARAT) to measurements taken by a blinded assessor were examined after completion of the intervention (2 weeks) and at 3 months from randomisation., Results: Forty patients were recruited and randomised (RSS n = 23; UC n = 17) with a recruitment rate of 9.5% (40/417) of patients admitted with a stroke of which 52 (12.5%) were potentially eligible, with 10 declining to participate for various reasons. Participants found the RSS intervention acceptable and adherence was good. The intervention was safe and there were no serious adverse events., Conclusions: This study indicates that recruitment to a trial of RSS in the acute period after stroke is feasible. The intervention was well tolerated and appeared to provide additional benefit to usual care. In addition to a definitive trial of efficacy, further work is warranted to examine the effects of varying doses of RSS upon arm function and the mechanism by which RSS induces sensorimotor recovery in the acute period after stroke., Trial Registration: ISRCTN, registry no: ISRCTN17422343 ; IRAS Project ID: 215137. Registered on October 2016.
- Published
- 2019
- Full Text
- View/download PDF
23. The macrocyclizing protease butelase 1 remains autocatalytic and reveals the structural basis for ligase activity.
- Author
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James AM, Haywood J, Leroux J, Ignasiak K, Elliott AG, Schmidberger JW, Fisher MF, Nonis SG, Fenske R, Bond CS, and Mylne JS
- Subjects
- Arabidopsis genetics, Biological Evolution, Catalysis, Catalytic Domain, Clitoria genetics, Crystallography, X-Ray, Cyclization, Cysteine Endopeptidases chemistry, Cysteine Endopeptidases genetics, Ligases chemistry, Ligases genetics, Models, Structural, Mutation, Plant Proteins chemistry, Plant Proteins genetics, Plant Proteins metabolism, Recombinant Proteins, Seed Storage Proteins genetics, Seed Storage Proteins metabolism, Arabidopsis enzymology, Clitoria enzymology, Cysteine Endopeptidases metabolism, Ligases metabolism
- Abstract
Plant asparaginyl endopeptidases (AEPs) are expressed as inactive zymogens that perform maturation of seed storage protein upon cleavage-dependent autoactivation in the low-pH environment of storage vacuoles. The AEPs have attracted attention for their macrocyclization reactions, and have been classified as cleavage or ligation specialists. However, we have recently shown that the ability of AEPs to produce either cyclic or acyclic products can be altered by mutations to the active site region, and that several AEPs are capable of macrocyclization given favorable pH conditions. One AEP extracted from Clitoria ternatea seeds (butelase 1) is classified as a ligase rather than a protease, presenting an opportunity to test for loss of cleavage activity. Here, making recombinant butelase 1 and rescuing an Arabidopsis thaliana mutant lacking AEP, we show that butelase 1 retains cleavage functions in vitro and in vivo. The in vivo rescue was incomplete, consistent with some trade-off for butelase 1 specialization toward macrocyclization. Its crystal structure showed an active site with only subtle differences from cleaving AEPs, suggesting the many differences in its peptide-binding region are the source of its efficient macrocyclization. All considered, it seems that either butelase 1 has not fully specialized or a requirement for autocatalytic cleavage is an evolutionary constraint upon macrocyclizing AEPs., (© 2019 The Authors The Plant Journal © 2019 John Wiley & Sons Ltd.)
- Published
- 2019
- Full Text
- View/download PDF
24. An Ancient Peptide Family Buried within Vicilin Precursors.
- Author
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Zhang J, Payne CD, Pouvreau B, Schaefer H, Fisher MF, Taylor NL, Berkowitz O, Whelan J, Rosengren KJ, and Mylne JS
- Subjects
- Amino Acid Sequence, Proteolysis, Sequence Homology, Amino Acid, Tandem Mass Spectrometry, Seed Storage Proteins chemistry
- Abstract
New proteins can evolve by duplication and divergence or de novo, from previously noncoding DNA. A recently observed mechanism is for peptides to evolve within a "host" protein and emerge by proteolytic processing. The first examples of such interstitial peptides were ones hosted by precursors for seed storage albumin. Interstitial peptides have also been observed in precursors for seed vicilins, but current evidence for vicilin-buried peptides (VBPs) is limited to seeds of the broadleaf plants pumpkin and macadamia. Here, an extensive sequence analysis of vicilin precursors suggested that peptides buried within the N-terminal region of preprovicilins are widespread and truly ancient. Gene sequences indicative of interstitial peptides were found in species from Amborellales to eudicots and include important grass and legume crop species. We show the first protein evidence for a monocot VBP in date palm seeds as well as protein evidence from other crops including the common tomato, sesame and pumpkin relatives, cucumber, and the sponge loofah ( Luffa aegyptiaca). Their excision was consistent with asparaginyl endopeptidase-mediated maturation, and sequences were confirmed by tandem mass spectrometry. Our findings suggest that the family is large and ancient and that based on the NMR solution structures for loofah Luffin P1 and tomato VBP-8, VBPs adopt a helical hairpin fold stapled by two internal disulfide bonds. The first VBPs characterized were a protease inhibitor, antimicrobials, and a ribosome inactivator. The age and evolutionary retention of this peptide family suggest its members play important roles in plant biology.
- Published
- 2019
- Full Text
- View/download PDF
25. Labor and birth: knowledge, reflection, and different perspectives.
- Author
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Teixeira LA, Nakano AR, and Nucci MF
- Subjects
- Brazil, Cesarean Section statistics & numerical data, Cesarean Section trends, Female, Humans, Medical Overuse, Pregnancy, Labor, Obstetric, Medicalization trends, Parturition, Social Class
- Published
- 2018
- Full Text
- View/download PDF
26. A family of small, cyclic peptides buried in preproalbumin since the Eocene epoch.
- Author
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Fisher MF, Zhang J, Taylor NL, Howard MJ, Berkowitz O, Debowski AW, Behsaz B, Whelan J, Pevzner PA, and Mylne JS
- Abstract
Orbitides are cyclic ribosomally-synthesized and post-translationally modified peptides (RiPPs) from plants; they consist of standard amino acids arranged in an unbroken chain of peptide bonds. These cyclic peptides are stable and range in size and topologies making them potential scaffolds for peptide drugs; some display valuable biological activities. Recently two orbitides whose sequences were buried in those of seed storage albumin precursors were said to represent the first observable step in the evolution of larger and hydrophilic bicyclic peptides. Here, guided by transcriptome data, we investigated peptide extracts of 40 species specifically for the more hydrophobic orbitides and confirmed 44 peptides by tandem mass spectrometry, as well as obtaining solution structures for four of them by NMR. Acquiring transcriptomes from the phylogenetically important Corymboideae family confirmed the precursor genes for the peptides (called PawS1-Like or PawL1 ) are confined to the Asteroideae, a subfamily of the huge plant family Asteraceae. To be confined to the Asteroideae indicates these peptides arose during the Eocene epoch around 45 Mya. Unlike other orbitides, all PawL-derived Peptides contain an Asp residue, needed for processing by asparaginyl endopeptidase. This study has revealed what is likely to be a very large new family of orbitides, uniquely buried alongside albumin and processed by asparaginyl endopeptidase.
- Published
- 2018
- Full Text
- View/download PDF
27. Forces That Supplement Visuomotor Learning: A "Sensory Crossover" Experiment.
- Author
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Bittmann MF and Patton JL
- Subjects
- Adult, Female, Humans, Male, Reproducibility of Results, Sensitivity and Specificity, Stress, Mechanical, Feedback, Sensory physiology, Learning physiology, Movement physiology, Perceptual Masking physiology, Psychomotor Performance physiology, Touch physiology, Visual Perception physiology
- Abstract
Previous studies on reaching movements have shown that people can adapt to either visuomotor (e.g., prism glasses) or mechanical distortions (e.g., force fields) through repetitive practice. Recent work has shown that adaptation to one type of distortion might have implications on learning the other type, suggesting that neural resources are common to both kinematic and kinetic adaptation. This study investigated whether training with a novel force field might benefit the learning of a visual distortion-specifically, when forces were designed to produce aftereffects that aligned with the ideal trajectory for a visual rotation. Participants training with these forces (Force Group) were tested on a visual rotation. After training with this novel field, we found that participants had surprisingly good performance in the visual rotation condition, comparable to a group that trained on the visual rotation directly. A third group tested the rate of learning with intermittent catch trials, where we zeroed the forces and switched to the visual rotation, and found a significantly faster learning rate than the group that trained directly on the visual rotation. Interestingly, these abilities continued to significantly improve one day later, whereas the direct training showed no such effect. All participants were able to generalize what they learned to unpracticed movement directions. We speculate that when forces are used in training, haptic feedback can have a substantial influence on learning a task that heavily relies on visual feedback. Such methods can impact any situation where one might add robotic forces to the training process.
- Published
- 2017
- Full Text
- View/download PDF
28. Transfer of dynamic motor skills acquired during isometric training to free motion.
- Author
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Melendez-Calderon A, Tan M, Bittmann MF, Burdet E, and Patton JL
- Subjects
- Adult, Arm physiology, Feedback, Physiological, Female, Humans, Learning, Male, Motion, Isometric Contraction, Motor Skills, Task Performance and Analysis
- Abstract
Recent studies have explored the prospects of learning to move without moving, by displaying virtual arm movement related to exerted force. However, it has yet to be tested whether learning the dynamics of moving can transfer to the corresponding movement. Here we present a series of experiments that investigate this isometric training paradigm. Subjects were asked to hold a handle and generate forces as their arms were constrained to a static position. A precise simulation of reaching was used to make a graphic rendering of an arm moving realistically in response to the measured interaction forces and simulated environmental forces. Such graphic rendering was displayed on a horizontal display that blocked their view to their actual (statically constrained) arm and encouraged them to believe they were moving. We studied adaptation of horizontal, planar, goal-directed arm movements in a velocity-dependent force field. Our results show that individuals can learn to compensate for such a force field in a virtual environment and transfer their new skills to the actual free motion condition, with performance comparable to practice while moving. Such nonmoving techniques should impact various training conditions when moving may not be possible. NEW & NOTEWORTHY This study provided early evidence supporting that training movement skills without moving is possible. In contrast to previous studies, our study involves 1 ) exploiting cross-modal sensory interactions between vision and proprioception in a motionless setting to teach motor skills that could be transferable to a corresponding physical task, and 2 ) evaluates the movement skill of controlling muscle-generated forces to execute arm movements in the presence of external forces that were only virtually present during training., (Copyright © 2017 the American Physiological Society.)
- Published
- 2017
- Full Text
- View/download PDF
29. Stepwise Evolution of a Buried Inhibitor Peptide over 45 My.
- Author
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Jayasena AS, Fisher MF, Panero JL, Secco D, Bernath-Levin K, Berkowitz O, Taylor NL, Schilling EE, Whelan J, and Mylne JS
- Subjects
- Amino Acid Motifs, Amino Acid Sequence, Biological Evolution, Evolution, Molecular, Models, Molecular, Mutagenesis, Insertional genetics, Peptides, Peptides, Cyclic metabolism, Phylogeny, Prealbumin genetics, Protein Precursors genetics, Seeds genetics, Helianthus genetics, Peptides, Cyclic genetics
- Abstract
The de novo evolution of genes and the novel proteins they encode has stimulated much interest in the contribution such innovations make to the diversity of life. Most research on this de novo evolution focuses on transcripts, so studies on the biochemical steps that can enable completely new proteins to evolve and the time required to do so have been lacking. Sunflower Preproalbumin with SFTI-1 (PawS1) is an unusual albumin precursor because in addition to producing albumin it also yields a potent, bicyclic protease-inhibitor called SunFlower Trypsin Inhibitor-1 (SFTI-1). Here, we show how this inhibitor peptide evolved stepwise over tens of millions of years. To trace the origin of the inhibitor peptide SFTI-1, we assembled seed transcriptomes for 110 sunflower relatives whose evolution could be resolved by a chronogram, which allowed dates to be estimated for the various stages of molecular evolution. A genetic insertion event in an albumin precursor gene ∼45 Ma introduced two additional cleavage sites for protein maturation and conferred duality upon PawS1-Like genes such that they also encode a small buried macrocycle. Expansion of this region, including two Cys residues, enlarged the peptide ∼34 Ma and made the buried peptides bicyclic. Functional specialization into a protease inhibitor occurred ∼23 Ma. These findings document the evolution of a novel peptide inside a benign region of a pre-existing protein. We illustrate how a novel peptide can evolve without de novo gene evolution and, critically, without affecting the function of what becomes the protein host., (© The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2017
- Full Text
- View/download PDF
30. Diverse cyclic seed peptides in the Mexican zinnia (Zinnia haageana).
- Author
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Franke B, Jayasena AS, Fisher MF, Swedberg JE, Taylor NL, Mylne JS, and Rosengren KJ
- Subjects
- Peptides, Cyclic isolation & purification, Protein Structure, Secondary, Seed Storage Proteins isolation & purification, Asteraceae chemistry, Nuclear Magnetic Resonance, Biomolecular, Peptides, Cyclic chemistry, Seed Storage Proteins chemistry
- Abstract
A new family of small plant peptides was recently described and found to be widespread throughout the Millereae and Heliantheae tribes of the sunflower family Asteraceae. These peptides originate from the post-translational processing of unusual seed-storage albumin genes, and have been termed PawS-derived peptides (PDPs). The prototypic family member is a 14-residue cyclic peptide with potent trypsin inhibitory activity named SunFlower Trypsin Inhibitor (SFTI-1). In this study we present the features of three new PDPs discovered in the seeds of the sunflower species Zinnia haageana by a combination of de novo transcriptomics and liquid chromatography-mass spectrometry. Two-dimensional solution NMR spectroscopy was used to elucidate their structural characteristics. All three Z. haageana peptides have well-defined folds with a head-to-tail cyclized peptide backbone and a single disulfide bond. Although two possess an anti-parallel β-sheet structure, like SFTI-1, the Z. haageana peptide PDP-21 has a more irregular backbone structure. Despite structural similarities with SFTI-1, PDP-20 was not able to inhibit trypsin, thus the functional roles of these peptides is yet to be discovered. Defining the structural features of the small cyclic peptides found in the sunflower family will be useful for guiding the exploitation of these peptides as scaffolds for grafting and protein engineering applications., (© 2016 Wiley Periodicals, Inc.)
- Published
- 2016
- Full Text
- View/download PDF
31. Redefining the structural motifs that determine RNA binding and RNA editing by pentatricopeptide repeat proteins in land plants.
- Author
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Cheng S, Gutmann B, Zhong X, Ye Y, Fisher MF, Bai F, Castleden I, Song Y, Song B, Huang J, Liu X, Xu X, Lim BL, Bond CS, Yiu SM, and Small I
- Subjects
- Amino Acid Motifs, Amino Acid Sequence, Embryophyta metabolism, Mitochondria metabolism, Models, Molecular, Molecular Sequence Annotation, Plant Proteins genetics, Plant Proteins metabolism, Plastids metabolism, Protein Transport, RNA Recognition Motif Proteins chemistry, RNA Recognition Motif Proteins genetics, RNA Recognition Motif Proteins metabolism, RNA, Plant genetics, Sequence Alignment, Embryophyta genetics, Models, Structural, Plant Proteins chemistry, RNA Editing genetics
- Abstract
The pentatricopeptide repeat (PPR) proteins form one of the largest protein families in land plants. They are characterised by tandem 30-40 amino acid motifs that form an extended binding surface capable of sequence-specific recognition of RNA strands. Almost all of them are post-translationally targeted to plastids and mitochondria, where they play important roles in post-transcriptional processes including splicing, RNA editing and the initiation of translation. A code describing how PPR proteins recognise their RNA targets promises to accelerate research on these proteins, but making use of this code requires accurate definition and annotation of all of the various nucleotide-binding motifs in each protein. We have used a structural modelling approach to define 10 different variants of the PPR motif found in plant proteins, in addition to the putative deaminase motif that is found at the C-terminus of many RNA-editing factors. We show that the super-helical RNA-binding surface of RNA-editing factors is potentially longer than previously recognised. We used the redefined motifs to develop accurate and consistent annotations of PPR sequences from 109 genomes. We report a high error rate in PPR gene models in many public plant proteomes, due to gene fusions and insertions of spurious introns. These consistently annotated datasets across a wide range of species are valuable resources for future comparative genomics studies, and an essential pre-requisite for accurate large-scale computational predictions of PPR targets. We have created a web portal (http://www.plantppr.com) that provides open access to these resources for the community., (© 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.)
- Published
- 2016
- Full Text
- View/download PDF
32. Patterns of dengue virus IgM and IgG antibodies in suspected cases of dengue in Jamaica, 2003-2006.
- Author
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Brown MG, Vickers IE, Salas RA, and Smikle MF
- Subjects
- Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, Child, Child, Preschool, Dengue epidemiology, Disease Outbreaks, Female, Humans, Immunoglobulin G blood, Immunoglobulin M blood, Infant, Infant, Newborn, Jamaica epidemiology, Male, Middle Aged, Seasons, Seroepidemiologic Studies, Young Adult, Antibodies, Viral blood, Dengue immunology, Dengue Virus immunology
- Abstract
The patterns of dengue immunoglobulin (Ig) M and IgG antibodies in patients presenting with dengue-like illnesses during 2003-2006 were investigated using enzyme linked immunosorbent assays (ELISA). The seroprevalence of dengue antibodies, dengue IgM and dengue IgG antibodies were 59.4% (979/1647), 15.4% (254/1647) and 51.1% (841/1647), respectively. A statistically significantly increasing trend in the prevalence of dengue IgG antibodies with age was observed, ranging from 38.4% in patients aged less than 1 year to 90% in those 60 of years and over (p = 0.000; 95% confidence interval (CI) = 0.000-0.002). Conversely the seroprevalence of dengue IgM did not differ significantly with age and no seasonality in the number of cases was observed. The patterns of IgM and IgG antibodies found in the present study are consistent with those found in dengue endemic countries during inter-epidemic periods indicating that an increasing risk of a new dengue outbreak due to the accumulation of susceptible population. Preventive measures should be maintained to control the endemic spread and reduce the risk of outbreaks of dengue in Jamaica. The high seroprevalence rate of dengue IgG antibodies might have implications for the emergence of the more severe forms dengue infection in the Jamaican population.
- Published
- 2009
- Full Text
- View/download PDF
33. Challenges and strategies for proper pediatric nutrition and weight control.
- Author
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Morgan R, Paul SM, and Fisher MF
- Subjects
- Adolescent, Adult, Child, Humans, Nutritional Status, Obesity epidemiology, Prevalence, Program Development, United States epidemiology, Child Nutritional Physiological Phenomena, Health Promotion, Obesity prevention & control, Pediatrics
- Abstract
Pediatric and adolescent obesity are a growing problem in New Jersey and throughout the United States. The long-term health consequences may produce a generation of children with a shorter life expectancy than their parents have. A coordinated effort by parents, teachers, physicians, public health organizations, schools, and peers is essential in encouraging children who are currently overweight to lose weight and attain a normal body mass index and to prevent other children from becoming overweight.
- Published
- 2004
34. The need to improve continuing medical education.
- Author
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Fisher MF
- Subjects
- Humans, Referral and Consultation, Education, Medical, Continuing, Nuclear Medicine education, Radiology education
- Published
- 1996
35. Competing modalities.
- Author
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Fisher MF
- Subjects
- Humans, Magnetic Resonance Imaging, Sensitivity and Specificity, Diagnostic Imaging
- Published
- 1994
- Full Text
- View/download PDF
36. Total therapeutic embolization of the kidney for hypertension in a child with a mycotic aneurysm.
- Author
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Cohen AM, Fisher MF, and Yoon YS
- Subjects
- Child, Endocarditis, Bacterial complications, Humans, Hypertension, Renovascular diagnostic imaging, Hypertension, Renovascular etiology, Male, Radiography, Renal Artery, Aneurysm, Infected complications, Embolization, Therapeutic, Hypertension, Renovascular therapy
- Abstract
A 7-year-old boy with bacterial endocarditis developed renal artery mycotic aneurysm and diffuse distal occlusions of the renal branches. Blood pressure in the patient returned to normal after obliteration of flow to the left kidney with Gelfoam, Ivalon, and a Gianturco coil. An end loop of the coil used for embolization remained in the lumen of the aorta against its lateral side. Improper coil placement did not result in complications; the boy later died due to neurologic and pulmonary complications. We discuss the therapeutic potential of renal embolization, as well as the risks of particulate and ethanol embolization, in the treatment of renal vascular hypertension from mycotic aneurysms.
- Published
- 1983
- Full Text
- View/download PDF
37. Abdominal lipoblastomatosis: radiographic, echographic, and computed tomographic findings.
- Author
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Fisher MF, Fletcher BD, Dahms BB, Haller JO, and Friedman AP
- Subjects
- Abdominal Neoplasms diagnostic imaging, Abdominal Neoplasms pathology, Adipose Tissue pathology, Female, Humans, Infant, Lipoma diagnostic imaging, Lipoma pathology, Tomography, X-Ray Computed, Ultrasonography, Abdominal Neoplasms diagnosis, Lipoma diagnosis
- Abstract
Two cases of lipoblastomatosis in infants are described. Radiography, ultrasonography, and computerized tomography showed well-defined soft-tissue densities embedded within large masses of adipose tissue. This appearance, which may be specific for lipoblastomatosis, correlated precisely with the pathologic appearance of lobules of immature adipose tissue surrounding masses of myxoid tissue.
- Published
- 1981
- Full Text
- View/download PDF
38. Growth, Sporulation and Aflatoxin Production by Aspergillus parasiticus on Strained Baby Foods.
- Author
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Llewellyn GC, Duckhardt NE, Fisher MF, Eadie T, and O'Rear CE
- Abstract
The potential for aflatoxin production by Aspergillus parasiticus on strained baby food was evaluated. Four puréed foods were inoculated with the mold and cultured at 15 and 26 C in two series of experiments. The aflatoxigenic mold produced mycelia and sporulated at both temperatures. The foods ranked in mean total yield of aflatoxin (μg/g of substrate) in the following order: peas > squash > green beans > pears. The ranking held consistent for both temperatures. Aflatoxins B
1 and G1 were produced in higher percentages than B2 and G2 in each food at both temperatures. At 26 C, total aflatoxin produced ranged from 8 to 71 μg/g of substrate, and at 15 C, the mean for the four foods was from 3 to 50 μg/g of substrate. Temperature and substrate were the primary variables which contributed to sporulation rate, toxin production and toxin ratios. Peas and squash should be considered primary and highly supportive substrates for aflatoxin production if conditions should arise for spores to contaminate the products either during or after processing. Absolute prevention of aflatoxigenic spore contamination in these foods studied is essential. An occasional testing of these foods for aflatoxin seems warranted. A lower temperature during aflatoxin formation decreased the total toxin formed, but did not prohibit aflatoxin occurrence. A lower temperature also tended to divert the type of toxin produced from B1 to the less dangerous G1 and G2 . Aflatoxin would appear to be a problem in these foods only under rare and unusual circumstances in relation to processing and consumer usage. If such aflatoxigenic spore contamination should occur, the levels produced would be significant.- Published
- 1980
- Full Text
- View/download PDF
39. Renal stone extraction through a percutaneous nephrostomy in a renal transplant patient.
- Author
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Fisher MF, Haaga JR, Persky L, Eckel RE, and LiPuma J
- Subjects
- Contrast Media, Drainage, Humans, Hydronephrosis complications, Kidney physiopathology, Kidney Calculi complications, Kidney Calculi diagnostic imaging, Kidney Transplantation, Male, Middle Aged, Punctures, Radiography, Kidney surgery, Kidney Calculi surgery, Urinary Diversion methods
- Published
- 1982
- Full Text
- View/download PDF
40. In- 111-labeled leukocyte imaging: false-positive study due to acute gastrointestinal bleeding.
- Author
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Fisher MF and Rudd TG
- Subjects
- Aged, False Positive Reactions, Humans, Male, Radioisotopes, Radionuclide Imaging, Gastrointestinal Hemorrhage complications, Indium, Infections diagnostic imaging, Leukocytes
- Abstract
A case is reported in which In- 111-labeled leukocytes accumulated in the left colon on a 24-hr delayed image. This was found to be secondary to an upper gastrointestinal bleed in progress at the time of injection of the radiolabeled leukocytes.
- Published
- 1983
41. Likelihood ratio.
- Author
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Fisher MF
- Subjects
- Diagnostic Errors, Humans, Radionuclide Imaging, Statistics as Topic, Hemangioma diagnostic imaging, Liver Neoplasms diagnostic imaging
- Published
- 1987
- Full Text
- View/download PDF
42. Scintigraphic demonstration of acute gastrointestinal bleeding in a colonic interposition.
- Author
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Fisher MF, Lipuma JP, and Agnone J
- Subjects
- Acute Disease, Adult, Female, Gastrectomy methods, Humans, Postoperative Complications diagnostic imaging, Radionuclide Imaging, Colon surgery, Esophagus surgery, Gastrointestinal Hemorrhage diagnostic imaging
- Published
- 1982
- Full Text
- View/download PDF
43. A new classification of ventilators based on methods of sterilisation.
- Author
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Fisher MF and McClelland RM
- Subjects
- Sterilization, Ventilators, Mechanical classification
- Published
- 1971
- Full Text
- View/download PDF
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