RESUMO
Vesicle trafficking is a fundamental process that allows for the sorting and transport of specific proteins (i.e., "cargoes") to different compartments of eukaryotic cells. Cargo recognition primarily occurs through coats and the associated proteins at the donor membrane. However, it remains unclear whether cargoes can also be selected at other stages of vesicle trafficking to further enhance the fidelity of the process. The WDR11-FAM91A1 complex functions downstream of the clathrin-associated AP-1 complex to facilitate protein transport from endosomes to the TGN. Here, we report the cryo-EM structure of human WDR11-FAM91A1 complex. WDR11 directly and specifically recognizes a subset of acidic clusters, which we term super acidic clusters (SACs). WDR11 complex assembly and its binding to SAC-containing proteins are indispensable for the trafficking of SAC-containing proteins and proper neuronal development in zebrafish. Our studies thus uncover that cargo proteins could be recognized in a sequence-specific manner downstream of a protein coat.
Assuntos
Microscopia Crioeletrônica , Transporte Proteico , Peixe-Zebra , Humanos , Animais , Endossomos/metabolismo , Células HEK293 , Células HeLa , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/química , Ligação ProteicaRESUMO
Ferroptosis is a form of programmed cell death that is pathogenic to several acute and chronic diseases and executed via oxygenation of polyunsaturated phosphatidylethanolamines (PE) by 15-lipoxygenases (15-LO) that normally use free polyunsaturated fatty acids as substrates. Mechanisms of the altered 15-LO substrate specificity are enigmatic. We sought a common ferroptosis regulator for 15LO. We discovered that PEBP1, a scaffold protein inhibitor of protein kinase cascades, complexes with two 15LO isoforms, 15LO1 and 15LO2, and changes their substrate competence to generate hydroperoxy-PE. Inadequate reduction of hydroperoxy-PE due to insufficiency or dysfunction of a selenoperoxidase, GPX4, leads to ferroptosis. We demonstrated the importance of PEBP1-dependent regulatory mechanisms of ferroptotic death in airway epithelial cells in asthma, kidney epithelial cells in renal failure, and cortical and hippocampal neurons in brain trauma. As master regulators of ferroptotic cell death with profound implications for human disease, PEBP1/15LO complexes represent a new target for drug discovery.
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Injúria Renal Aguda/patologia , Asma/patologia , Lesões Encefálicas Traumáticas/patologia , Morte Celular , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Injúria Renal Aguda/metabolismo , Animais , Apoptose , Asma/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Isoenzimas/metabolismo , Lipoxigenase/química , Lipoxigenase/metabolismo , Camundongos , Modelos Moleculares , Oxazolidinonas/farmacologia , Oxirredução , Proteína de Ligação a Fosfatidiletanolamina/químicaRESUMO
The cause of insulin resistance in obesity and type 2 diabetes mellitus (T2DM) is not limited to impaired insulin signalling but also involves the complex interplay of multiple metabolic pathways. The analysis of large data sets generated by metabolomics and lipidomics has shed new light on the roles of metabolites such as lipids, amino acids and bile acids in modulating insulin sensitivity. Metabolites can regulate insulin sensitivity directly by modulating components of the insulin signalling pathway, such as insulin receptor substrates (IRSs) and AKT, and indirectly by altering the flux of substrates through multiple metabolic pathways, including lipogenesis, lipid oxidation, protein synthesis and degradation and hepatic gluconeogenesis. Moreover, the post-translational modification of proteins by metabolites and lipids, including acetylation and palmitoylation, can alter protein function. Furthermore, the role of the microbiota in regulating substrate metabolism and insulin sensitivity is unfolding. In this Review, we discuss the emerging roles of metabolites in the pathogenesis of insulin resistance and T2DM. A comprehensive understanding of the metabolic adaptations involved in insulin resistance may enable the identification of novel targets for improving insulin sensitivity and preventing, and treating, T2DM.
Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Resistência à Insulina/fisiologia , Animais , Transtornos do Metabolismo de Glucose/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina/genética , Metabolismo dos Lipídeos/fisiologia , Fígado/metabolismo , Redes e Vias Metabólicas , Metabolômica/métodos , Obesidade , Receptor de Insulina/metabolismo , Transdução de SinaisRESUMO
In female mouse embryos, somatic cells undergo a random form of X chromosome inactivation (XCI), whereas extraembryonic trophoblast cells in the placenta undergo imprinted XCI, silencing exclusively the paternal X chromosome. Initiation of imprinted XCI requires a functional maternal allele of the X-linked gene Rnf12, which encodes the ubiquitin ligase Rnf12/RLIM. We find that knockout (KO) of Rnf12 in female mammary glands inhibits alveolar differentiation and milk production upon pregnancy, with alveolar cells that lack RLIM undergoing apoptosis as they begin to differentiate. Genetic analyses demonstrate that these functions are mediated primarily by the paternal Rnf12 allele due to nonrandom maternal XCI in mammary epithelial cells. These results identify paternal Rnf12/RLIM as a critical survival factor for milk-producing alveolar cells and, together with population models, reveal implications of transgenerational epigenetic inheritance.
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Sobrevivência Celular , Glândulas Mamárias Animais/citologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Epigênese Genética , Feminino , Impressão Genômica , Masculino , Glândulas Mamárias Animais/fisiologia , Camundongos , Gravidez , Ubiquitina-Proteína Ligases/genética , Inativação do Cromossomo XRESUMO
Patent ductus arteriosus (PDA) is a common form of congenital heart disease. The MYH6 gene has important effects on cardiovascular growth and development, but the effect of variants in the MYH6 gene promoter on ductus arteriosus is unknown. DNA was extracted from blood samples of 721 subjects (428 patients with isolated and sporadic PDA and 293 healthy controls) and analyzed by sequencing for MYH6 gene promoter region variants. Cellular function experiments with three cell lines (HEK-293, HL-1, and H9C2 cells) and bioinformatics analyses were performed to verify their effects on gene expression. In the MYH6 gene promoter, 11 variants were identified. Four variants were found only in patients with PDA and 2 of them (g.3434G>C and g.4524C>T) were novel. Electrophoretic mobility shift assay showed that the transcription factors bound by the promoter variants were significantly altered in comparison to the wild-type in all three cell lines. Dual luciferase reporter showed that all the 4 variants reduced the transcriptional activity of the MYH6 gene promoter (P < 0.05). Prediction of transcription factors bound by the variants indicated that these variants alter the transcription factor binding sites. These pathological alterations most likely affect the contraction of the smooth muscle of ductus arteriosus, leading to PDA. This study is the first to focus on variants at the promoter region of the MYH6 gene in PDA patients with cellular function tests. Therefore, this study provides new insights to understand the genetic basis and facilitates further studies on the mechanism of PDA formation.
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Miosinas Cardíacas , Permeabilidade do Canal Arterial , Cadeias Pesadas de Miosina , Regiões Promotoras Genéticas , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Miosinas Cardíacas/genética , Estudos de Casos e Controles , Linhagem Celular , Permeabilidade do Canal Arterial/genética , Permeabilidade do Canal Arterial/patologia , Células HEK293 , Cadeias Pesadas de Miosina/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
N6-methyladenosine (m6A) and adenosine-to-inosine (A-to-I) editing are two of the most abundant RNA modifications, both at adenosines. Yet, the interaction of these two types of adenosine modifications is largely unknown. Here we show a global A-to-I difference between m6A-positive and m6A-negative RNA populations. Both the presence and extent of A-to-I sites in m6A-negative RNA transcripts suggest a negative correlation between m6A and A-to-I. Suppression of m6A-catalyzing enzymes results in global A-to-I RNA editing changes. Further depletion of m6A modification increases the association of m6A-depleted transcripts with adenosine deaminase acting on RNA (ADAR) enzymes, resulting in upregulated A-to-I editing on the same m6A-depleted transcripts. Collectively, the effect of m6A on A-to-I suggests a previously underappreciated interplay between two distinct and abundant RNA modifications, highlighting a complex epitranscriptomic landscape.
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Adenosina/análogos & derivados , Adenosina/química , Inosina/química , Edição de RNA/genética , RNA/genética , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Linhagem Celular Tumoral , Regulação da Expressão Gênica/genética , Células HEK293 , Células HeLa , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismoRESUMO
The large dsDNA viruses replicate their DNA as concatemers consisting of multiple covalently linked genomes. Genome packaging is catalyzed by a terminase enzyme that excises individual genomes from concatemers and packages them into preassembled procapsids. These disparate tasks are catalyzed by terminase alternating between two distinct states-a stable nuclease that excises individual genomes and a dynamic motor that translocates DNA into the procapsid. It was proposed that bacteriophage λ terminase assembles as an anti-parallel dimer-of-dimers nuclease complex at the packaging initiation site. In contrast, all characterized packaging motors are composed of five terminase subunits bound to the procapsid in a parallel orientation. Here, we describe biophysical and structural characterization of the λ holoenzyme complex assembled in solution. Analytical ultracentrifugation, small angle X-ray scattering, and native mass spectrometry indicate that 5 subunits assemble a cone-shaped terminase complex. Classification of cryoEM images reveals starfish-like rings with skewed pentameric symmetry and one special subunit. We propose a model wherein nuclease domains of two subunits alternate between a dimeric head-to-head arrangement for genome maturation and a fully parallel arrangement during genome packaging. Given that genome packaging is strongly conserved in both prokaryotic and eukaryotic viruses, the results have broad biological implications.
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Empacotamento do Genoma Viral , Montagem de Vírus , Montagem de Vírus/genética , Bacteriófago lambda/genética , Endodesoxirribonucleases/metabolismo , DNA , DNA Viral/metabolismo , Empacotamento do DNARESUMO
The phytohormone abscisic acid (ABA) plays a central role in regulating stomatal movements under drought conditions. The root-derived peptide CLAVATA3/EMBRYO SURROUNDING REGION-RELATED 25 (CLE25) moves from the root to shoot for activating ABA biosynthesis under drought conditions. However, the root-to-shoot translocation of root-derived ABA and its regulation of stomatal movements in the shoot remain to be clarified. Here, we reveal that the ABA transporter ATP-binding cassette subfamily G member 25 (AtABCG25) mediates root-to-shoot translocation of ABA and ABA-glucosyl ester (ABA-GE) in Arabidopsis (Arabidopsis thaliana). Isotope-labeled ABA tracer experiments and hormone quantification in xylem sap showed that the root-to-shoot translocation of ABA and ABA-GE was substantially impaired in the atabcg25 mutant under nondrought and drought conditions. However, the contents of ABA and ABA-GE in the leaves were lower in the atabcg25 mutant than in the wild type (WT) under nondrought but similar under drought conditions. Consistently, the stomatal closure was suppressed in the atabcg25 mutant under nondrought but not under drought conditions. The transporter activity assays showed that AtABCG25 directly exported ABA and ABA-GE in planta and in yeast (Saccharomyces cerevisiae) cells. Thus, we proposed a working model in which root-derived ABA transported by AtABCG25 via xylem mediates stomatal movements in the shoot under nondrought conditions but might exhibit little effect on stomatal movements under drought conditions. These findings extend the functions of AtABCG25 and provide insights into the long-distance translocation of ABA and its role in stomatal movements.
Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Raízes de Plantas , Brotos de Planta , Estômatos de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Ácido Abscísico/metabolismo , Estômatos de Plantas/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/metabolismo , Brotos de Planta/genética , Transporte Biológico , Secas , Mutação/genética , Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Reguladores de Crescimento de Plantas/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/genéticaRESUMO
Polyploidy is a significant mechanism in eukaryotic evolution and is particularly prevalent in the plant kingdom. However, our knowledge about this phenomenon and its effects on evolution remains limited. A major obstacle to the study of polyploidy is the great difficulty in untangling the origins of allopolyploids. Due to the drastic genome changes and the erosion of allopolyploidy signals caused by the combined effects of hybridization and complex post-polyploid diploidization processes, resolving the origins of allopolyploids has long been a challenging task. Here we revisit this issue with the interesting case of subtribe Tussilagininae (Asteraceae: Senecioneae) and by developing HomeoSorter, a new pipeline for network inferences by phasing homeologs to parental subgenomes. The pipeline is based on the basic idea of a previous study but with major changes to address the scaling problem and implement some new functions. With simulated data, we demonstrate that HomeoSorter works efficiently on genome-scale data and has high accuracy in identifying polyploid patterns and assigning homeologs. Using HomeoSorter, the maximum pseudo-likelihood model of Phylonet, and genome-scale data, we further address the complex origin of Tussilagininae, a speciose group (ca. 45 genera and 710 species) characterized by having high base chromosome numbers (mainly x = 30, 40). In particular, the inferred patterns are strongly supported by the chromosomal evidence. Tussilagininae is revealed to comprise two large groups with successive allopolyploid origins: Tussilagininae s.s. (mainly x = 30) and the Gynoxyoid group (x = 40). Two allopolyploidy events first give rise to Tussilagininae s.s., with the first event occurring between the ancestor of subtribe Senecioninae (x = 10) and a lineage (highly probably with x = 10) related to the Brachyglottis alliance, and the resulting hybrid lineage crossing with the ancestor of Chersodoma (x = 10) and leading to Tussilagininae s.s. Then, after early diversification, the Central American group (mainly x = 30) of Tussilagininae s.s., is involved in a third allopolyploidy event with, again, the Chersodoma lineage and produces the Gynoxyoid group. Our study highlights the value of HomeoSorter and the homeolog-sorting approach in polyploid phylogenetics. With rich species diversity and clear evolutionary patterns, Tussilagininae s.s. and the Gynoxyoid group are also excellent models for future investigations of polyploidy.
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Tandem mass tags (TMT) are widely used in proteomics to simultaneously quantify multiple samples in a single experiment. The tags can be easily added to the primary amines of peptides/proteins through chemical reactions. In addition to amines, TMT reagents also partially react with the hydroxyl groups of serine, threonine, and tyrosine residues under alkaline conditions, which significantly compromises the analytical sensitivity and precision. Under alkaline conditions, reducing the TMT molar excess can partially mitigate overlabeling of histidine-free peptides, but has a limited effect on peptides containing histidine and hydroxyl groups. Here, we present a method under acidic conditions to suppress overlabeling while efficiently labeling amines, using only one-fifth of the TMT amount recommended by the manufacturer. In a deep-scale analysis of a yeast/human two-proteome sample, we systematically evaluated our method against the manufacturer's method and a previously reported TMT-reduced method. Our method reduced overlabeled peptides by 9-fold and 6-fold, respectively, resulting in the substantial enhancement in peptide/protein identification rates. More importantly, the quantitative accuracy and precision were improved as overlabeling was reduced, endowing our method with greater statistical power to detect 42% and 12% more statistically significant yeast proteins compared to the standard and TMT-reduced methods, respectively. Mass spectrometric data have been deposited in the ProteomeXchange Consortium via the iProX partner repository with the data set identifier PXD047052.
Assuntos
Aminas , Proteoma , Proteômica , Espectrometria de Massas em Tandem , Proteoma/análise , Proteoma/química , Proteômica/métodos , Humanos , Aminas/química , Espectrometria de Massas em Tandem/métodos , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Peptídeos/química , Peptídeos/análise , Análise Custo-Benefício , Proteínas de Saccharomyces cerevisiae/análise , Proteínas de Saccharomyces cerevisiae/química , Coloração e Rotulagem/métodosRESUMO
BACKGROUND & AIMS: Hereditary tyrosinemia type 1 (HT1) results from the loss of fumarylacetoacetate hydrolase (FAH) activity and can lead to lethal liver injury. Therapeutic options for HT1 remain limited. In this study, we aimed to construct an engineered bacterium capable of reprogramming host metabolism and thereby provide a potential alternative approach for the treatment of HT1. METHODS: Escherichia coli Nissle 1917 (EcN) was engineered to express genes involved in tyrosine metabolism in the anoxic conditions that are characteristic of the intestine (EcN-HT). Bodyweight, survival rate, plasma (tyrosine/liver function), H&E staining and RNA sequencing were used to assess its ability to degrade tyrosine and protect against lethal liver injury in Fah-knockout (KO) mice, a well-accepted model of HT1. RESULTS: EcN-HT consumed tyrosine and produced L-DOPA (levodopa) in an in vitro system. Importantly, in Fah-KO mice, the oral administration of EcN-HT enhanced tyrosine degradation, reduced the accumulation of toxic metabolites, and protected against lethal liver injury. RNA sequencing analysis revealed that EcN-HT rescued the global gene expression pattern in the livers of Fah-KO mice, particularly of genes involved in metabolic signaling and liver homeostasis. Moreover, EcN-HT treatment was found to be safe and well-tolerated in the mouse intestine. CONCLUSIONS: This is the first report of an engineered live bacterium that can degrade tyrosine and alleviate lethal liver injury in mice with HT1. EcN-HT represents a novel engineered probiotic with the potential to treat this condition. IMPACT AND IMPLICATIONS: Patients with hereditary tyrosinemia type 1 (HT1) are characterized by an inability to metabolize tyrosine normally and suffer from liver failure, renal dysfunction, neurological impairments, and cancer. Given the overlap and complementarity between the host and microbial metabolic pathways, the gut microbiome provides a potential chance to regulate host metabolism through degradation of tyrosine and reduction of byproducts that might be toxic. Herein, we demonstrated that an engineered live bacterium, EcN-HT, could enhance tyrosine breakdown, reduce the accumulation of toxic tyrosine byproducts, and protect against lethal liver injury in Fah-knockout mice. These findings suggested that engineered live biotherapeutics that can degrade tyrosine in the gut may represent a viable and safe strategy for the prevention of lethal liver injury in HT1 as well as the mitigation of its associated pathologies.
Assuntos
Tirosinemias , Humanos , Camundongos , Animais , Tirosinemias/complicações , Tirosinemias/genética , Tirosinemias/metabolismo , Fígado/patologia , Modelos Animais de Doenças , Camundongos Knockout , Tirosina/metabolismo , Escherichia coli/genéticaRESUMO
Pathological cardiac hypertrophy is associated with adverse cardiovascular events and can gradually lead to heart failure, arrhythmia, and even sudden death. However, the current development of treatment strategies has been unsatisfactory. Therefore, it is of great significance to find new and effective drugs for the treatment of myocardial hypertrophy. We found that carnosol can inhibit myocardial hypertrophy induced by PE stimulation, and the effect is very significant at 5 µM. Moreover, we demonstrated that 50 mg/kg of carnosol protect against cardiac hypertrophy and fibrosis induced by TAC surgery in mice. Mechanically, we proved that the inhibitory effect of carnosol on cardiac hypertrophy depends on its regulation on the phosphorylation activation of AMPK. In conclusion, our study suggested that carnosol may be a novel drug component for the treatment of pathological cardiac hypertrophy.
Assuntos
Proteínas Quinases Ativadas por AMP , Abietanos , Cardiomegalia , Camundongos Endogâmicos C57BL , Miócitos Cardíacos , Animais , Abietanos/farmacologia , Abietanos/uso terapêutico , Cardiomegalia/tratamento farmacológico , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/prevenção & controle , Proteínas Quinases Ativadas por AMP/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacosRESUMO
Advanced vibrational spectroscopic experiments have reached a level of sophistication that can only be matched by numerical simulations in order to provide an unequivocal analysis, a crucial step to understand the structure-function relationship of biomolecules. While density functional theory (DFT) has become the standard method when targeting medium-size or larger systems, the problem of its reliability and accuracy are well-known and have been abundantly documented. To establish a reliable computational protocol, especially when accuracy is critical, a tailored benchmark is usually required. This is generally done over a short list of known candidates, with the basis set often fixed a priori. In this work, we present a systematic study of the performance of DFT-based hybrid and double-hybrid functionals in the prediction of vibrational energies and infrared intensities at the harmonic level and beyond, considering anharmonic effects through vibrational perturbation theory at the second order. The study is performed for the six-lowest energy glycine conformers, utilizing available "state-of-the-art" accurate theoretical and experimental data as reference. Focusing on the most intense fundamental vibrations in the mid-infrared range of glycine conformers, the role of the basis sets is also investigated considering the balance between computational cost and accuracy. Targeting larger systems, a broad range of hybrid schemes with different computational costs is also tested.
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The kinetically retarded sulfur evolution reactions and notorious lithium dendrites as the major obstacles hamper the practical implementation of lithium-sulfur batteries (LSBs). Dual metal atom catalysts as a new model are expected to show higher activity by their rational coupling. Herein, the dual-atom catalyst with coupled NiâCo atom pairs (Ni/Co-DAC) is designed successfully by programmed approaches. The NiâCo atom pairs alter the local electron structure and optimize the coordination configuration of Ni/Co-DAC, leading to the coupling effect for promoting the interconversion of sulfur and guiding lithium plating/striping. The LSB delivers a remarkable capacity of 818 mA h g-1 at 3.0 C and a low degeneration rate of 0.053% per cycle over 500 cycles. Moreover, the LSB with a high sulfur mass loading of 6.1 mg cm-2 and lean electrolyte dosage of 6.0 µL mgS -1 shows a remarkable areal capacity of 5.7 mA h cm-2.
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Wounds in harsh environments can face long-term inflammation and persistent infection, which can slow healing. Wound spray is a product that can be rapidly applied to large and irregularly dynamic wounds, and can quickly form a protective film in situ to inhibit external environmental infection. In this study, a biodegradable A and B combined multi-functional spray hydrogel is developed with methacrylate-modified chitosan (CSMA1st) and ferulic acid (FA) as type A raw materials and oxidized Bletilla striata polysaccharide (OBSP) as type B raw materials. The precursor CSMA1st-FA/OBSP (CSOB-FA1st) hydrogel is formed by the self-cross-linking of dynamic Schiff base bonds, the CSMA-FA/OBSP (CSOB-FA) hydrogel is formed quickly after UV-vis light, so that the hydrogel fits with the wound. Rapid spraying and curing provide sufficient flexibility and rapidity for wounds and the hydrogel has good injectability, adhesive, and mechanical strength. In rats and miniature pigs, the A and B combined spray hydrogel can shrink wounds and promote healing of infected wounds, and promote the enrichment of fibrocyte populations. Therefore, the multifunctional spray hydrogel combined with A and B can protect irregular dynamic wounds, prevent wound infection and secondary injury, and be used for safe and effective wound treatment, which has a good prospect for development.
Assuntos
Quitosana , Hidrogéis , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Hidrogéis/química , Quitosana/química , Ratos , Suínos , Reagentes de Ligações Cruzadas/química , Ratos Sprague-Dawley , Porco Miniatura , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologiaRESUMO
OBJECTIVES: To identify novel genetic elements facilitating the horizontal transfer of the oxazolidinone/phenicol resistance gene optrA and the pleuromutilin-lincosamide-streptogramin A resistance gene lsa(E) in Streptococcus suis. METHODS: The complete genomes of S. suis HB18 and two transconjugants were obtained using both the Illumina and Nanopore platforms. MICs were determined by broth microdilution. Inverse PCR was performed to identify circular forms of the novel unconventional circularizable structure (UCS), genomic island (GI) and integrative and conjugative element (ICE). Conjugation experiments assessed the transferability of optrA and lsa(E) genes in S. suis. RESULTS: S. suis HB18 carried a multiresistance gene cluster optrA-lsa(E)-lnu(B)-aphA-aadE-spw. This gene cluster, flanked by intact and truncated erm(B) in the same orientation, resided on a novel ICESsuHB18. Inverse PCR revealed the existence of a novel UCS, named UCS-optrAâ+âlsa(E), which could excise the gene cluster optrA-lsa(E)-lnu(B)-aphA-aadE-spw and one copy of erm(B) from ICESsuHB18. Two transconjugants with different characteristics were obtained. In transconjugant T-JH-GI, UCS-optrAâ+âlsa(E) excised from ICESsuHB18 inserted into the erm(B)-positive GI, designated GISsuHB18, generating the novel GISsuHB18-1. Meanwhile, in T-JH-ICE, genetic rearrangement events occurred in ICESsuHB18 and GISsuHB18, forming the novel ICESsuHB18-1. CONCLUSIONS: This is the first report demonstrating the functionally active UCS-optrAâ+âlsa(E) excising from ICESsuHB18 and inserting into the erm(B)-positive GISsuHB18 during the conjugation process. The location of optrA and lsa(E) on a multiresistance UCS enhances its persistence and dissemination.
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OBJECTIVES: Polymyxin-induced nephrotoxicity (PIN) is a major safety concern and challenge in clinical practice, which limits the clinical use of polymyxins. This study aims to investigate the risk factors and to develop a scoring tool for the early prediction of PIN. METHODS: Data on critically ill patients who received intravenous polymyxin B or colistin sulfate for over 24 h were collected. Logistic regression with the least absolute shrinkage and selection operator (LASSO) was used to identify variables that are associated with outcomes. The eXtreme Gradient Boosting (XGB) classifier algorithm was used to further visualize factors with significant differences. A prediction model for PIN was developed through binary logistic regression analysis and the model was assessed by temporal validation and external validation. Finally, a risk-scoring system was developed based on the prediction model. RESULTS: Of 508 patients, 161 (31.6%) patients developed PIN. Polymyxin type, loading dose, septic shock, concomitant vasopressors and baseline blood urea nitrogen (BUN) level were identified as significant predictors of PIN. All validation exhibited great discrimination, with the AUC of 0.742 (95% CI: 0.696-0.787) for internal validation, of 0.708 (95% CI: 0.605-0.810) for temporal validation and of 0.874 (95% CI: 0.759-0.989) for external validation, respectively. A simple risk-scoring tool was developed with a total risk score ranging from -3 to 4, corresponding to a risk of PIN from 0.79% to 81.24%. CONCLUSIONS: This study established a prediction model for PIN. Before using polymyxins, the simple risk-scoring tool can effectively identify patients at risk of developing PIN within a range of 7% to 65%.
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Antibacterianos , Humanos , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Antibacterianos/efeitos adversos , Idoso , Fatores de Risco , Polimixina B/efeitos adversos , Polimixina B/administração & dosagem , Projetos Piloto , Estado Terminal , Medição de Risco/métodos , Polimixinas/efeitos adversos , Colistina/efeitos adversos , Colistina/administração & dosagem , Modelos Logísticos , Adulto , Nefropatias/induzido quimicamenteRESUMO
Dual-targeted chimeric antigen receptor T (CAR-T) cell is an important strategy to improve the efficacy of CD19 CAR-T cell against refractory or relapsed B cell non-Hodgkin lymphoma (R/R B-NHL). However, durable responses are not achieved in most patients, in part owing CAR-T cell exhaustion caused by PD-1/PD-L1 pathway. We conducted a prospective, single-arm study of dual-targeted CD19/22 CAR-T cell combined with anti-PD-1 antibody, tislelizumab, in R/R B-NHL (NCT04539444). Tislelizumab was administrated on +1 day after patients received infusion of CD19/22 CAR-T cell. Responses, survival and safety were evaluated. From 1 August 2020 to 30 March 2023, 16 patients were enrolled. The median follow-up time is 16.0 (range: 5.0-32.0 months) months. Overall response was achieved in 14 of 16 (87.5%) patients, and the complete response (CR) was achieved in 11 of 16 (68.8%) patients. The 1-year progression-free survival and overall survival rates were 68.8% and 81.3%, respectively. Of the 14 patients responded, 9 patients maintained their response until the end of follow-up. Among the 15 out of 16 (93.8%) patients who had extranodal involvement, 14 (93.3%) patients achieved overall response rate with 11 (73.3%) patients achieving CR. Eight (50%) patients experienced cytokine release syndrome. No neurologic adverse events were reported. Gene Ontology-Biological Process enrichment analysis showed that immune response-related signaling pathways were enriched in CR patients. Our results suggest that CD19/22 CAR-T cell combined with tislelizumab elicit a safe and durable response in R/R B-NHL and may improve the prognosis of those patients.
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Anticorpos Monoclonais Humanizados , Linfoma de Células B , Receptores de Antígenos Quiméricos , Humanos , Linfócitos T , Estudos Prospectivos , Linfoma de Células B/tratamento farmacológicoRESUMO
Pupillary response, an important process in visual perception and social and emotional cognition, has been widely studied for understanding the neural mechanisms of neuropsychiatric disorders. However, there have been few studies on pupil response to social and non-social stimuli in animal models of neurodevelopmental disorders including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder. Here, we developed a pupilometer using a robust eye feature-detection algorithm for real-time pupillometry in dogs. In a pilot study, we found that a brief light flash induced a less-pronounced and slower pupil dilation response in gene-edited dogs carrying mutations in Shank3; mutations of its ortholog in humans were repeatedly identified in ASD patients. We further found that obnoxious, loud firecracker sound of 120 dB induced a stronger and longer pupil dilation response in Shank3 mutant dogs, whereas a high reward food induced a weaker pupillary response in Shank3 mutants than in wild-type control dogs. In addition, we found that Shank3 mutants showed compromised pupillary synchrony during dog-human interaction. These findings of altered pupil response in Shank3 mutant dogs recapitulate the altered sensory responses in ASD patients. Thus, this study demonstrates the validity and value of the pupilometer for dogs, and provides an effective paradigm for studying the underlying neural mechanisms of ASD and potentially other psychiatric disorders.
Assuntos
Transtorno do Espectro Autista , Humanos , Cães , Animais , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/psicologia , Pupila/fisiologia , Projetos Piloto , Emoções , Modelos Animais de DoençasRESUMO
INTRODUCTION: The contribution of individual and combined inflammatory markers for the prognosis of acute ischemic stroke (AIS) remains elusive. This study investigated the effect of systemic inflammatory response index (SIRI), and neutrophil to high-density lipoprotein ratio (NHR), which is mediated by fasting blood glucose (FBG), on 90-day prognosis of patients with AIS. METHODS: In this pre-specified substudy of an observational cohort study, 2,828 patients with AIS were enrolled from the Nanjing Stroke Registry between January 2017 and July 2021. Peripheral venous blood was collected from patients fasting for at least 8 h within 24 h of admission to gather information on the following parameters: neutrophil count, lymphocyte count, monocyte count, HDL level, and fasting blood glucose level. Then, the SIRI and NHR values were calculated. Following this, the correlation among SIRI, NHR, and modified Rankin Scale (mRS) scores 90 days after onset was examined via univariate and multivariate logistic analyses. Lastly, mediation analysis was performed to examine the relationship between systematic inflammatory response and study outcomes mediated by FBG. RESULTS: SIRI and NHR were both negatively correlated with clinical outcomes (p < 0.05). Logistic regression analysis revealed that SIRI and NHR were independently associated with poor outcomes after adjusting for potential confounders. Subgroup analyses further validated these correlations. Meanwhile, mediation analysis corroborated that FBG partially mediated the associations between SIRI and a poor prognosis at 90 days (indirect effect estimate = 0.0038, bootstrap 95% CI 0.001-0.008; direct effect estimate = 0.1719, bootstrap 95% CI 0.1258-0.2179). Besides, FBG also played a mediating role between NHR and poor outcomes (indirect effect estimate = 0.0066, bootstrap 95% CI 0.002-0.120; direct effect estimate = 0.1308, bootstrap 95% CI 0.0934-0.1681). CONCLUSION: Our study demonstrated that SIRI and NHR are positively associated with poor clinical and mortality outcomes at 90 days in AIS patients, which was partially mediated by FBG.