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Single-particle cryo-electron tomography is an emerging technique capable of determining the structure of proteins imaged within the native context of cells at molecular resolution. While high-throughput techniques for sample preparation and tilt-series acquisition are beginning to provide sufficient data to allow structural studies of proteins at physiological concentrations, the complex data analysis pipeline and the demanding storage and computational requirements pose major barriers for the development and broader adoption of this technology. Here, we present a scalable, end-to-end framework for single-particle cryo-electron tomography data analysis from on-the-fly pre-processing of tilt series to high-resolution refinement and classification, which allows efficient analysis and visualization of datasets with hundreds of tilt series and hundreds of thousands of particles. We validate our approach using in vitro and cellular datasets, demonstrating its effectiveness at achieving high-resolution and revealing conformational heterogeneity in situ. The framework is made available through an intuitive and easy-to-use computer application, nextPYP ( http://nextpyp.app ).
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Tomografía con Microscopio Electrónico , Programas Informáticos , Tomografía con Microscopio Electrónico/métodos , Microscopía por Crioelectrón/métodos , Proteínas , Procesamiento de Imagen Asistido por Computador/métodosRESUMEN
MOTIVATION: When analyzing 1D time series, scientists are often interested in identifying regions where one variable depends linearly on the other. Typically, they use an ad hoc and therefore often subjective method to do so. RESULTS: Here, we develop a statistically rigorous, Bayesian approach to infer the optimal partitioning of a dataset not only into contiguous piece-wise linear segments, but also into contiguous segments described by linear combinations of arbitrary basis functions. We therefore present a general solution to the problem of identifying discontinuous change points. Focusing on microbial growth, we use the algorithm to find the range of optical density where this density is linearly proportional to the number of cells and to automatically find the regions of exponential growth for both Escherichia coli and Saccharomyces cerevisiae. For budding yeast, we consequently are able to infer the Monod constant for growth on fructose. Our algorithm lends itself to automation and high throughput studies, increases reproducibility, and should facilitate data analyses for a broad range of scientists. AVAILABILITY AND IMPLEMENTATION: The corresponding Python package, entitled Nunchaku, is available at PyPI: https://pypi.org/project/nunchaku.
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Algoritmos , Programas Informáticos , Teorema de Bayes , Reproducibilidad de los Resultados , Saccharomyces cerevisiaeRESUMEN
Experimental autoimmune encephalomyelitis (EAE) is a mouse model that can be used to investigate aetiology, pathogenesis, and treatment approaches for multiple sclerosis (MS). A novel integrated bioinformatics approach was used to understand the involvement of differentially expressed genes (DEGs) in the spleen of EAE mice through data mining of existing microarray and RNA-seq datasets. We screened differentially expressed mRNAs using mRNA expression profile data of EAE spleens taken from Gene Expression Omnibus (GEO). Functional and pathway enrichment analyses of DEGs were performed by Database for Annotation, Visualization, and Integrated Discovery (DAVID). Subsequently, the DEGs-encoded protein-protein interaction (PPI) network was constructed. The 784 DEGs in GSE99300 A.SW PP-EAE mice spleen mRNA profiles, 859 DEGs in GSE151701 EAE mice spleen mRNA profiles, and 646 DEGs in GSE99300 SJL/J PP-EAE mice spleen mRNA profiles were explored. Functional enrichment of 55 common DEGs among 3 sub-datasets revealed several immune-related terms, such as neutrophil extravasation, leucocyte migration, antimicrobial humoral immune response mediated by an antimicrobial peptide, toll-like receptor 4 bindings, IL-17 signalling pathway, and TGF-beta signalling pathway. In the screening of 10 hub genes, including MPO, ELANE, CTSG, LTF, LCN2, SELP, CAMP, S100A9, ITGA2B, and PRTN3, and in choosing and validating the 5 DEGs, including ANK1, MBOAT2, SLC25A21, SLC43A1, and SOX6, the results showed that SLC43A1 and SOX6 were significantly decreased in EAE mice spleen. Thus this study offers a list of genes expressed in the spleen that might play a key role in the pathogenesis of EAE.
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Encefalomielitis Autoinmune Experimental , Ratones , Animales , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/metabolismo , Bazo/patología , ARN Mensajero/genética , Biología Computacional/métodos , Perfilación de la Expresión GénicaRESUMEN
The discovery and development of new drugs against malaria remain urgent. Aspartate transcarbamoylase (ATC) has been suggested to be a promising target for antimalarial drug development. Here, we describe a series of small-molecule inhibitors of P. falciparum ATC with low nanomolar binding affinities that selectively bind to a previously unreported allosteric pocket, thereby inhibiting ATC activation. We demonstrate that the buried allosteric pocket is located close to the traditional ATC active site and that reported compounds maintain the active site of PfATC in its low substrate affinity/low activity conformation. These compounds inhibit parasite growth in blood stage cultures at single digit micromolar concentrations, whereas limited effects were seen against human normal lymphocytes. To our knowledge, this series represent the first PfATC-specific allosteric inhibitors.
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Antimaláricos , Malaria Falciparum , Humanos , Antimaláricos/farmacología , Antimaláricos/química , Plasmodium falciparum , Ácido Aspártico/metabolismo , Dominio CatalíticoRESUMEN
Deepening our understanding of mammalian gut microbiota has been greatly hampered by the lack of a facile, real-time, and in vivo bacterial imaging method. To address this unmet need in microbial visualization, we herein report the development of a second near-infrared (NIR-II)-based method for in vivo imaging of gut bacteria. Using d-propargylglycine in gavage and then click reaction with an azide-containing NIR-II dye, gut microbiota of a donor mouse was strongly labeled with NIR-II fluorescence on their peptidoglycan. The bacteria could be readily visualized in recipient mouse gut with high spatial resolution and deep tissue penetration under NIR irradiation. The NIR-II-based metabolic labeling strategy reported herein, provides, to the best of our knowledge, the first protocol for facile in vivo visualization of gut microbiota within deep tissues, and offers an instrumental tool for deciphering the complex biology of these gut "dark matters".
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Colorantes Fluorescentes/química , Microbioma Gastrointestinal , Imagen Óptica , Peptidoglicano/química , Animales , Colorantes Fluorescentes/metabolismo , Rayos Infrarrojos , Ratones , Estructura Molecular , Peptidoglicano/metabolismoRESUMEN
Our ability to predict evolutionary trajectories of pathogens in response to antibiotic pressure is one of the promising leverage to fight against the present antibiotic resistance worldwide crisis. Yet, few studies tackled this question in situ at the outbreak level, due to the difficulty to link a given pathogenic clone evolution with its precise antibiotic exposure over time. In this study, we monitored the real-time evolution of an Aeromonas salmonicida clone in response to successive antibiotic and vaccine therapies in a commercial fish farm. The clone was responsible for a four-year outbreak of furunculosis within a Recirculating Aquaculture System Salmo salar farm in China, and we reconstructed the precise tempo of mobile genetic elements (MGEs) acquisition events during this period. The resistance profile provided by the acquired MGEs closely mirrored the antibiotics used to treat the outbreak, and we evidenced that two subclonal groups developed similar resistances although unrelated MGE acquisitions. Finally, we also demonstrated the efficiency of vaccination in outbreak management and its positive effect on antibiotic resistance prevalence. Our study provides unprecedented knowledge critical to understand evolutionary trajectories of resistant pathogens outside the laboratory.
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Aeromonas salmonicida/fisiología , Antibacterianos/farmacología , Evolución Molecular Dirigida , Enfermedades de los Peces/microbiología , Aeromonas salmonicida/efectos de los fármacos , Animales , Acuicultura , China , Farmacorresistencia Microbiana/genética , Forunculosis/microbiologíaRESUMEN
As a well-studied biochemical reduction process in environmental microbiology, extracellular electron transfer (EET) was recently discovered in bacteria closely related to human health, and orthologues of a flavin-based EET gene were found in the genomes of many species across Firmicutes, a major phylum in mammalian gut microbiota. However, EET has not yet been confirmed to occur in mammalian gut, the presence of which may have broad physiological influences. Toward this end, here we first confirmed the occurrence of EET in mouse gut microbiotas cultured in vitro. Cyclic voltammetry analysis was then performed by directly inserting electrodes into the mouse cecum under anaerobic conditions, and a characteristic catalytic wave was observed in the gut of conventional but not germ-free mouse, proving the existence of in vivo bacterial EET. We also detected similar catalytic waves in the cecal microbiotas of rat and guinea pig in vivo, suggesting EET's high prevalence in mammalian intestines. Our finding on the bacterial electron production in mammalian guts offers a new bioelectrochemical scope for deciphering the complex microbiology of gut bacteria and its effects on host physiology.
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Transporte de Electrón , Microbioma Gastrointestinal/fisiología , Intestinos/microbiología , Animales , Antibacterianos/farmacología , Dinitrocresoles/química , Electroquímica/métodos , Firmicutes/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Cobayas , Listeria monocytogenes/química , Mamíferos , Ratones Endogámicos C57BL , Polimixina B/farmacología , Vancomicina/farmacologíaRESUMEN
OBJECTIVE: To study the predictive value of Pediatric Age-adapted Sequential Organ Failure Assessment Score (pSOFA), Pediatric Risk of Mortality Score III (PRISM III), and Pediatric Critical Illness Score (PCIS) in children with severe sepsis. METHODS: A retrospective analysis was performed for the clinical data of 193 hospitalized children with severe sepsis. According to the final outcome, these children were divided into a survival group with 151 children and a death group with 42 children. The scores of pSOFA, PRISM III, and PCIS were determined according to the worst values of each index within 24 hours after admission. The receiver operating characteristic (ROC) curve was used to analyze the efficiency of each scoring system in predicting the risk of death due to sepsis. Smooth curve fitting was used to analyze the correlation between the three scoring systems and the threshold effect of each scoring system. Decision curve analysis (DCA) was used to evaluate the application value of each scoring system. RESULTS: The ROC analysis showed that PCIS and pSOFA had a similar predictive value (P=0.182) and that PRISM III and pSOFA had a similar predictive value (P=0.210), while PRISM III had a better predictive value than PCIS (P=0.045). PRISM III had the highest degree of fitting with prognosis, followed by pSOFA and PCIS. The DCA analysis showed that when the risk of death was 0.4 and 0.6 in children with severe sepsis and the three scoring systems were used as the basis for emergency intervention decision-making, pSOFA achieved the highest standardized net benefit, followed by PRISM III and PCIS. CONCLUSIONS: All three scoring systems have a certain value in predicting the prognosis of children with severe sepsis, and pSOFA has a better value than PRISM III and PCIS.
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Puntuaciones en la Disfunción de Órganos , Sepsis , Niño , Enfermedad Crítica , Humanos , Pronóstico , Curva ROC , Estudios RetrospectivosRESUMEN
A series of propargylamides containing an electron-rich benzene ring was prepared through the Ugi reaction of 3,5-dimethoxyaniline with various propiolic acids, aldehydes and isocyanides. Subjecting these adducts to a gold-catalyzed intramolecular alkyne hydroarylation process allowed to efficiently construct the 2-quinolone core bearing a branched substituent on the nitrogen atom.
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Tetracycline antibiotics are widely used in livestock, and tetracycline resistance genes (TRG) are frequently reported in the manure of farmed animals. However, the diversity of TRG-carrying transposons in manure has still been rarely investigated. Using a culture-free functional metagenomic procedure, combined with large-insert library construction and sequencing, bioinformatic analyses, and functional experiments, we identified 17 distinct TRGs in a single pig manure sample, including two new tet genes: tet(59), encoding a tetracycline efflux pump, and tet(W/N/W), encoding mosaic ribosomal protection. Our study also revealed six new TRG-carrying putative nonconjugative transposons: Tn5706-like transposon Tn6298, IS200/605-related transposon Tn6303, Tn3 family transposon Tn6299, and three ISCR2-related transposons, Tn62300, Tn62301, and Tn62302 IMPORTANCE: Fertilization of agricultural fields with animal manure is believed to play a major role in antibiotic resistance dissemination in the environment. There is growing concern for the possible spread of antibiotic resistance from the environment to humans since genetic resistance determinants may be located in transposons and other mobile genetic elements potentially transferable to pathogens. Among the various antibiotic resistance genes found in manure, tetracycline resistance genes (TRGs) are some of the most common. The present study provides a detailed snapshot of the tetracycline mobilome in a single pig manure sample, revealing an unappreciated diversity of TRGs and potential TRG mobility vectors. Our precise identification of the TRG-carrying units will enable us to investigate in more details their mobility effectiveness.
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Elementos Transponibles de ADN , Genes Bacterianos , Estiércol/microbiología , Microbiología del Suelo , Resistencia a la Tetraciclina/genética , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , China , Biología Computacional , Biblioteca de Genes , Variación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Ganado , Metagenómica , Sus scrofa , PorcinosRESUMEN
Aspartate transcarbamoylase (ATC) is the first committed step in de novo pyrimidine biosynthesis in eukaryotes and plants. A potent transition state analog of human ATCase (PALA) has previously been assessed in clinical trials for the treatment of cancer, but was ultimately unsuccessful. Additionally, inhibition of this pathway has been proposed to be a target to suppress cell proliferation in E. coli, the malarial parasite and tuberculosis. In this manuscript we screened a 70-member library of ATC inhibitors developed against the malarial and tubercular ATCases for inhibitors of the human ATC. Four compounds showed low nanomolar inhibition (IC50 30-120â nM) in an inâ vitro activity assay. These compounds significantly outperform PALA, which has a triphasic inhibition response under identical conditions, in which significant activity remains at PALA concentrations above 10â µM. Evidence for a druggable allosteric pocket in human ATC is provided by both inâ vitro enzyme kinetic, homology modeling and in silico docking. These compounds also suppress the proliferation of U2OS osteoblastoma cells by promoting cell cycle arrest in G0/G1 phase. This report provides the first evidence for an allosteric pocket in human ATC, which greatly enhances its druggability and demonstrates the potential of this series in cancer therapy.
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Aspartato Carbamoiltransferasa , Proliferación Celular , Inhibidores Enzimáticos , Osteosarcoma , Humanos , Proliferación Celular/efectos de los fármacos , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Osteosarcoma/metabolismo , Aspartato Carbamoiltransferasa/antagonistas & inhibidores , Aspartato Carbamoiltransferasa/metabolismo , Aspartato Carbamoiltransferasa/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/síntesis química , Regulación Alostérica/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Relación Estructura-Actividad , Relación Dosis-Respuesta a Droga , Simulación del Acoplamiento Molecular , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular Tumoral , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Neoplasias Óseas/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismoRESUMEN
OBJECTIVE: To compare the clinical features and co-infection between pneumonia caused by influenza virus A (IVA) and pneumonia caused by influenza virus B (IVB) among children. METHODS: A total of 165 children with pneumonia caused by influenza virus (IV) were included in the study. These subjects were divided into IVA(n=71) and IVB pneumonia groups (n=94) according to the subtypes of IV. The IVA pneumonia group was further divided into simple infection (n=14) and co-infection subgroups (n=57), and the IVB pneumonia group was also further divided into simple infection (n=27) and co-infection subgroups (n=67). Co-infection rate and pathogen spectrum were analysed in children with IV pneumonia. RESULTS: The IVB pneumonia group had significantly increased mean age of onset and significantly prolonged mean duration of fever compared with the IVA pneumonia group (P<0.05). Co-infection rate among children with IV pneumonia was 75.2%, who were co-infected with bacteria (44.2%), Mycoplasma pneumoniae (MP, 21.8%) and other viruses (45.5%). Respiratory syncytial virus (RSV) was most common in children co-infected viruses (89% ). The rate of co-infection with RSV was significantly higher in the IVA pneumonia group than in the IVB pneumonia group. There were no significant differences in age, length of hospital stay, duration of fever, percentage of neutrophils, prealbumin, C-reactive protein, alanine aminotransferase, and creatine kinase-MB between the simple infection and co-infection subgroups of each group. CONCLUSIONS: Children with IVB pneumonia have prolonged duration of fever and increased age of onset compared with those with IVA pneumonia. Co-infection rate is high among children with IV pneumonia, who may be co-infected with bacteria, viruses and MP. Co-infection with RSV is more common in children with IVA pneumonia. It is difficult to identify the presense of co-infection using clinical indices.
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Coinfección/epidemiología , Virus de la Influenza A , Virus de la Influenza B , Gripe Humana/virología , Neumonía Viral/virología , Edad de Inicio , Niño , Preescolar , Femenino , Fiebre/etiología , Humanos , MasculinoRESUMEN
OBJECTIVE: Sirtuin (SIRT)1, as a molecular link between immunity and metabolic pathways, is a key immune response regulator. The significance of SIRT1 in peripheral blood mononuclear cells (PBMCs) of neuromyelitis optica spectrum disorder (NMOSD) has not been investigated. Here, we aimed to evaluate the SIRT1 mRNA level in PBMCs of patients with NMOSD and its clinical relevance and explore the potential mechanism of SIRT1 action. METHODS: A total of 65 patients with NMOSD and 60 normal controls from North China were enrolled. Using real-time fluorescence quantitative-polymerase chain reaction, mRNA levels were detected in PBMCs, and protein levels were detected using western blotting. RESULTS: Compared to the healthy controls and chronic-phase patients with NMOSD, SIRT1 mRNA and protein levels in PBMCs of NMOSD patients with acute attack were significantly downregulated (p < 0.0001). ∆EDSS scores (EDSS scores in the acute phase-EDSS scores before the recent attack) were higher in NMOSD patients with low SIRT1 mRNA level than in patients with high SIRT1 expression (p = 0.042). SIRT1 mRNA level in patients with acute-phase NMSOD was positively correlated with lymphocyte and monocyte counts and negatively correlated with neutrophil counts and the neutrophil-to-lymphocyte ratio. Furthermore, the transcription factor FOXP3 mRNA level was significantly positively correlated with the SIRT1 mRNA level in PBMCs of patients with acute-phase NMOSD. CONCLUSIONS: Our study indicated that SIRT1 mRNA expression was downregulated in the PBMCs of patients with acute-phase NMOSD, and its level was correlated with the clinical parameters of the patients, suggesting a potential role of SIRT1 in NMOSD.
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Neuromielitis Óptica , Humanos , Leucocitos Mononucleares/metabolismo , ARN Mensajero/metabolismo , Sirtuina 1/genética , Recuento de LeucocitosRESUMEN
Aspartate transcarbamoylase (ATCase) plays a key role in the second step of de novo pyrimidine biosynthesis in eukaryotes and has been proposed to be a target to suppress cell proliferation in E. coli, human cells and the malarial parasite. We hypothesized that a library of ATCase inhibitors developed for malarial ATCase (PfATCase) may also contain inhibitors of the tubercular ATCase and provide a similar inhibition of cellular proliferation. Of the 70 compounds screened, 10 showed single-digit micromolar inhibition in an inâ vitro activity assay and were tested for their effect on M.â tuberculosis cell growth in culture. The most promising compound demonstrated a MIC90 of 4â µM. A model of MtbATCase was generated using the experimental coordinates of PfATCase. In silico docking experiments showed this compound can occupy a similar allosteric pocket on MtbATCase to that seen on PfATCase, explaining the observed species selectivity seen for this compound series.
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Escherichia coli , Mycobacterium tuberculosis , Humanos , Ácido AspárticoRESUMEN
Understanding material surfaces and interfaces is vital in applications such as catalysis or electronics. By combining energies from electronic structure with statistical mechanics, ab initio simulations can, in principle, predict the structure of material surfaces as a function of thermodynamic variables. However, accurate energy simulations are prohibitive when coupled to the vast phase space that must be statistically sampled. Here we present a bi-faceted computational loop to predict surface phase diagrams of multicomponent materials that accelerates both the energy scoring and statistical sampling methods. Fast, scalable and data-efficient machine learning interatomic potentials are trained on high-throughput density-functional-theory calculations through closed-loop active learning. Markov chain Monte Carlo sampling in the semigrand canonical ensemble is enabled by using virtual surface sites. The predicted surfaces for GaN(0001), Si(111) and SrTiO3(001) are in agreement with past work and indicate that the proposed strategy can model complex material surfaces and discover previously unreported surface terminations.
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OBJECTIVE: To investigate the epidemiological features of influenza virus B (IVB) in the winter and the clinical features of pediatric pneumonia caused by IVB only. METHODS: A retrospective study was performed on the clinical data of children with respiratory infection who received pathogen testing and therapy at Soochow University Affiliated Children's Hospital during the winters of 2008, 2009, 2010 and 2011. RESULTS: The positive rates of influenza viruses A and B in the winters of 2008, 2009, and 2010 were 0.89%, 5.49%, and 6.24% respectively; the positive rate of influenza viruses A and B in the winter of 2011 was 8.72%, significantly higher than those in 2008-2010. The positive rates of IVB in the winters of 2008, 2009, and 2010 were 0%, 0%, and 0.21% respectively; the positive rate of IVB in the winter of 2011 was 5.36%, which was significantly higher than in the years 2008 to 2010. Pneumonia caused by IVB was confirmed in 94 children during the winter of 2011, including 27 cases of pneumonia caused by IVB only. Most of children with pneumonia caused by IVB only were aged over 6 months. The common symptoms in the 27 children caused by IVB only were fever (85%), runny nose (89%), and cough (100%). Wheezing (26%) and dyspnea (7%) were also seen in some cases. Among the 27 children, 19% showed abnormal white blood cell count, 30% showed increased C-reactive protein, 70% showed decreased prealbumin, and none showed visible organ dysfunction. No specific imaging findings were seen in the children with pneumonia caused by IVB only. However, many abnormal humoral and cellular immunological parameters were found in the majority of these children. The average length of hospital stay was approximately one week, there were no critical patients and the prognosis was good. CONCLUSIONS: Influenza viruses were at a peak level in inpatient children in the winter of 2011. IVB infection rate was gradually increasing. In children with pneumonia caused by IVB only, there are few critical patients, the symptoms are nonspecific and the prognosis is good.
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Virus de la Influenza B , Gripe Humana/epidemiología , Neumonía Viral/epidemiología , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Gripe Humana/diagnóstico , Gripe Humana/inmunología , Tiempo de Internación , Masculino , Neumonía Viral/diagnóstico , Neumonía Viral/inmunología , Estudios RetrospectivosRESUMEN
Malaria remains one of the most prominent and dangerous tropical diseases. While artemisinin and analogs have been used as first-line drugs for the past decades, due to the high mutational rate and rapid adaptation to the environment of the parasite, it remains urgent to develop new antimalarials. The pyrimidine biosynthesis pathway plays an important role in cell growth and proliferation. Unlike human host cells, the malarial parasite lacks a functional pyrimidine salvage pathway, meaning that RNA and DNA synthesis is highly dependent on the de novo synthesis pathway. Thus, direct or indirect blockage of the pyrimidine biosynthesis pathway can be lethal to the parasite. Aspartate transcarbamoylase (ATCase), catalyzes the second step of the pyrimidine biosynthesis pathway, the condensation of L-aspartate and carbamoyl phosphate to form N-carbamoyl aspartate and inorganic phosphate, and has been demonstrated to be a promising target both for anti-malaria and anti-cancer drug development. This is highlighted by the discovery that at least one of the targets of Torin2 - a potent, yet unselective, antimalarial - is the activity of the parasite transcarbamoylase. Additionally, the recent discovery of an allosteric pocket of the human homology raises the intriguing possibility of species selective ATCase inhibitors. We recently exploited the available crystal structures of the malarial aspartate transcarbamoylase to perform a fragment-based screening to identify hits. In this review, we summarize studies on the structure of Plasmodium falciparum ATCase by focusing on an allosteric pocket that supports the catalytic mechanisms.
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Antimaláricos , Aspartato Carbamoiltransferasa , Antimaláricos/química , Aspartato Carbamoiltransferasa/antagonistas & inhibidores , Aspartato Carbamoiltransferasa/química , Ácido Aspártico/química , Cristalografía por Rayos X , Descubrimiento de Drogas , Plasmodium falciparum/enzimología , Proteínas Protozoarias/antagonistas & inhibidores , Proteínas Protozoarias/químicaRESUMEN
IL-17a is a major inflammation target, with several approved antibodies in clinical use. Small-molecule IL-17a antagonists are an emerging hot topic, with the recent advancement of three compounds into clinical trials. Here, we describe the design, discovery, synthesis, and screening of macrocyclic compounds that bind to IL-17a. We found that all currently described IL-17a modifiers belong to the same pharmacophore model, likely resulting in a similar receptor binding mode on IL-17a. A pipeline of pharmacophore analysis, virtual screening, resynthesis, and protein biophysics resulted in a potent IL-17a macrocyclic modifier.
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The gut microbiota plays an integral role in human health and its dysbiosis is associated with many chronic diseases. There are still large gaps in understanding the host and environmental factors that directly regulate the gut microbiota, and few effective strategies exist to modulate the microbiota in therapeutic applications. Recent reports suggest that certain microRNAs (miRNAs) released by mammalian cells can regulate bacterial gene expression to influence the microbiome composition and propose extracellular vesicles as one natural mechanism for miRNA transport in the gut. These new findings interface with a burgeoning body of data showing that miRNAs are present in a stable form in extracellular environments and can mediate cell-to-cell communication in mammals. Here, we review the literature on RNA-mediated modulation of the microbiome to bring cross-disciplinary perspective to this new type of interaction and its potential implications in biology and medicine.
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BACKGROUND: Post-stroke depression (PSD) has a significant effect on patients' quality of life and is often accompanied by a decrease in serum brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) levels. Although exercise is an effective way to improve the body's endocrine environment, traditional high-intensity resistance exercise is not yet readily accepted. PURPOSE: To compare the acute effects of high and low resistance training with or without blood flow restriction on perception, BDNF, and VEGF levels in patients with PSD. METHOD: A total of 24 patients with PSD participated in 2 40% 1- Repetition Maximum (RM) low-intensity resistance training sessions (the low-intensity resistance training group (LOW group) had no blood flow restriction belt; the low-intensity blood flow restriction group (L-BFR group) was required to wear a 120-160 mmHg pressure cuff at the proximal end of the limb) and 1 80% 1-RM high-intensity resistance training session (HIGH group). Elbow venous blood was collected before and after exercise to test for ratings of perceived exertion (RPE), serum blood lactic acid (BLA), BDNF, and VEGF levels. RESULT AND CONCLUSION: There were no statistical differences between the RPE, BLA, BDNF, and VEGF levels of each group before exercise. After exercise, the RPE, BLA, and BDNF levels of the LOW group increased significantly (P < 0.05); the change in VEGF level of the LOW group was not significantly different from that before exercise (P > 0.05), and the indexes of the L-BFR group and the HIGH group were significant after the increase in exercise (P < 0.05). Analysis between groups showed that the changes in BLA, BDNF, and VEGF levels in the L-BFR group and HIGH group were higher than those in the LOW group, and the statistical difference was significant (P < 0.05); there was no change between the statistical difference of the L-BFR group and HIGH group (P > 0.05). The difference in RPE before and after exercise in the HIGH group was significantly higher than that in the L-BFR group (P < 0.05) and the difference in RPE before and after exercise in the L-BFR group was significantly higher than that in the LOW group (P < 0.05). Blood flow restriction resistance exercise may increase the serum BNDF and VEGF levels of PSD patients by increasing the body's BLA concentration. Although its effect is similar to that of traditional high-intensity resistance exercise, subjective physical strength is lower during blood flow restriction resistance exercise.