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1.
Cell ; 186(7): 1352-1368.e18, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-37001500

RESUMO

Resilience enables mental elasticity in individuals when rebounding from adversity. In this study, we identified a microcircuit and relevant molecular adaptations that play a role in natural resilience. We found that activation of parvalbumin (PV) interneurons in the primary auditory cortex (A1) by thalamic inputs from the ipsilateral medial geniculate body (MG) is essential for resilience in mice exposed to chronic social defeat stress. Early attacks during chronic social defeat stress induced short-term hyperpolarizations of MG neurons projecting to the A1 (MGA1 neurons) in resilient mice. In addition, this temporal neural plasticity of MGA1 neurons initiated synaptogenesis onto thalamic PV neurons via presynaptic BDNF-TrkB signaling in subsequent stress responses. Moreover, optogenetic mimicking of the short-term hyperpolarization of MGA1 neurons, rather than merely activating MGA1 neurons, elicited innate resilience mechanisms in response to stress and achieved sustained antidepressant-like effects in multiple animal models, representing a new strategy for targeted neuromodulation.


Assuntos
Córtex Auditivo , Camundongos , Animais , Córtex Auditivo/metabolismo , Tálamo/fisiologia , Neurônios/metabolismo , Corpos Geniculados , Interneurônios/fisiologia , Parvalbuminas/metabolismo
2.
Mol Cell ; 83(4): 637-651.e9, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36764303

RESUMO

Nonsense mutations create premature termination codons (PTCs), activating the nonsense-mediated mRNA decay (NMD) pathway to degrade most PTC-containing mRNAs. The undegraded mRNA is translated, but translation terminates at the PTC, leading to no production of the full-length protein. This work presents targeted PTC pseudouridylation, an approach for nonsense suppression in human cells. Specifically, an artificial box H/ACA guide RNA designed to target the mRNA PTC can suppress both NMD and premature translation termination in various sequence contexts. Targeted pseudouridylation exhibits a level of suppression comparable with that of aminoglycoside antibiotic treatments. When targeted pseudouridylation is combined with antibiotic treatment, a much higher level of suppression is observed. Transfection of a disease model cell line (carrying a chromosomal PTC) with a designer guide RNA gene targeting the PTC also leads to nonsense suppression. Thus, targeted pseudouridylation is an RNA-directed gene-specific approach that suppresses NMD and concurrently promotes PTC readthrough.


Assuntos
Códon sem Sentido , Biossíntese de Proteínas , Humanos , Códon sem Sentido/genética , Degradação do RNAm Mediada por Códon sem Sentido , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
Mol Cell ; 83(11): 1887-1902.e8, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37244254

RESUMO

Interleukin-1ß (IL-1ß) is a key protein in inflammation and contributes to tumor progression. However, the role of IL-1ß in cancer is ambiguous or even contradictory. Here, we found that upon IL-1ß stimulation, nicotinamide nucleotide transhydrogenase (NNT) in cancer cells is acetylated at lysine (K) 1042 (NNT K1042ac) and thereby induces the mitochondrial translocation of p300/CBP-associated factor (PCAF). This acetylation enhances NNT activity by increasing the binding affinity of NNT for NADP+ and therefore boosts NADPH production, which subsequently sustains sufficient iron-sulfur cluster maintenance and protects tumor cells from ferroptosis. Abrogating NNT K1042ac dramatically attenuates IL-1ß-promoted tumor immune evasion and synergizes with PD-1 blockade. In addition, NNT K1042ac is associated with IL-1ß expression and the prognosis of human gastric cancer. Our findings demonstrate a mechanism of IL-1ß-promoted tumor immune evasion, implicating the therapeutic potential of disrupting the link between IL-1ß and tumor cells by inhibiting NNT acetylation.


Assuntos
NADP Trans-Hidrogenases , Neoplasias , Humanos , NADP Trans-Hidrogenases/genética , NADP Trans-Hidrogenases/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Acetilação , Processamento de Proteína Pós-Traducional , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/genética
4.
Immunity ; 54(6): 1245-1256.e5, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34004140

RESUMO

We examined how baseline CD4+ T cell repertoire and precursor states impact responses to pathogen infection in humans using primary immunization with yellow fever virus (YFV) vaccine. YFV-specific T cells in unexposed individuals were identified by peptide-MHC tetramer staining and tracked pre- and post-vaccination by tetramers and TCR sequencing. A substantial number of YFV-reactive T cells expressed memory phenotype markers and contained expanded clones in the absence of exposure to YFV. After vaccination, pre-existing YFV-specific T cell populations with low clonal diversity underwent limited expansion, but rare populations with a reservoir of unexpanded TCRs generated robust responses. These altered dynamics reorganized the immunodominance hierarchy and resulted in an overall increase in higher avidity T cells. Thus, instead of further increasing the representation of dominant clones, YFV vaccination recruits rare and more responsive T cells. Our findings illustrate the impact of vaccines in prioritizing T cell responses and reveal repertoire reorganization as a key component of effective vaccination.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Vacina contra Febre Amarela/imunologia , Febre Amarela/imunologia , Vírus da Febre Amarela/imunologia , Adulto , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Células Cultivadas , Chlorocebus aethiops , Humanos , Receptores de Antígenos de Linfócitos T/imunologia , Vacinação/métodos , Células Vero , Febre Amarela/virologia
5.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678587

RESUMO

Deep learning-based multi-omics data integration methods have the capability to reveal the mechanisms of cancer development, discover cancer biomarkers and identify pathogenic targets. However, current methods ignore the potential correlations between samples in integrating multi-omics data. In addition, providing accurate biological explanations still poses significant challenges due to the complexity of deep learning models. Therefore, there is an urgent need for a deep learning-based multi-omics integration method to explore the potential correlations between samples and provide model interpretability. Herein, we propose a novel interpretable multi-omics data integration method (DeepKEGG) for cancer recurrence prediction and biomarker discovery. In DeepKEGG, a biological hierarchical module is designed for local connections of neuron nodes and model interpretability based on the biological relationship between genes/miRNAs and pathways. In addition, a pathway self-attention module is constructed to explore the correlation between different samples and generate the potential pathway feature representation for enhancing the prediction performance of the model. Lastly, an attribution-based feature importance calculation method is utilized to discover biomarkers related to cancer recurrence and provide a biological interpretation of the model. Experimental results demonstrate that DeepKEGG outperforms other state-of-the-art methods in 5-fold cross validation. Furthermore, case studies also indicate that DeepKEGG serves as an effective tool for biomarker discovery. The code is available at https://github.com/lanbiolab/DeepKEGG.


Assuntos
Biomarcadores Tumorais , Aprendizado Profundo , Recidiva Local de Neoplasia , Humanos , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/genética , Biologia Computacional/métodos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Genômica/métodos , Multiômica
6.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38446740

RESUMO

Protein annotation has long been a challenging task in computational biology. Gene Ontology (GO) has become one of the most popular frameworks to describe protein functions and their relationships. Prediction of a protein annotation with proper GO terms demands high-quality GO term representation learning, which aims to learn a low-dimensional dense vector representation with accompanying semantic meaning for each functional label, also known as embedding. However, existing GO term embedding methods, which mainly take into account ancestral co-occurrence information, have yet to capture the full topological information in the GO-directed acyclic graph (DAG). In this study, we propose a novel GO term representation learning method, PO2Vec, to utilize the partial order relationships to improve the GO term representations. Extensive evaluations show that PO2Vec achieves better outcomes than existing embedding methods in a variety of downstream biological tasks. Based on PO2Vec, we further developed a new protein function prediction method PO2GO, which demonstrates superior performance measured in multiple metrics and annotation specificity as well as few-shot prediction capability in the benchmarks. These results suggest that the high-quality representation of GO structure is critical for diverse biological tasks including computational protein annotation.


Assuntos
Benchmarking , Biologia Computacional , Ontologia Genética , Aprendizagem , Anotação de Sequência Molecular
7.
J Neurosci ; 44(7)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38124211

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by persistent deficits in social communication and stereotyped behaviors. Although major advances in basic research on autism have been achieved in the past decade, and behavioral interventions can mitigate the difficulties that individuals with autism experience, little is known about the many fundamental issues of the interventions, and no specific medication has demonstrated efficiency for the core symptoms of ASD. Intermittent hypobaric hypoxia (IHH) is characterized by repeated exposure to lowered atmospheric pressure and oxygen levels, which triggers multiple physiological adaptations in the body. Here, using two mouse models of ASD, male Shank3B -/- and Fmr1 -/y mice, we found that IHH training at an altitude of 5,000 m for 4 h per day, for 14 consecutive days, ameliorated autistic-like behaviors. Moreover, IHH training enhanced hypoxia inducible factor (HIF) 1α in the dorsal raphe nucleus (DRN) and activated the DRN serotonergic neurons. Infusion of cobalt chloride into the DRN, to mimic IHH in increasing HIF1α expression or genetically knockdown PHD2 to upregulate HIF1α expression in the DRN serotonergic neurons, alleviated autistic-like behaviors in Shank3B -/- mice. In contrast, downregulation of HIF1α in DRN serotonergic neurons induced compulsive behaviors. Furthermore, upregulating HIF1α in DRN serotonergic neurons increased the firing rates of these neurons, whereas downregulation of HIF1α in DRN serotonergic neurons decreased their firing rates. These findings suggest that IHH activated DRN serotonergic neurons via upregulation of HIF1α, and thus ameliorated autistic-like phenotypes, providing a novel therapeutic option for ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Camundongos , Masculino , Animais , Transtorno Autístico/genética , Transtorno Autístico/terapia , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/terapia , Núcleo Dorsal da Rafe , Neurônios Serotoninérgicos/fisiologia , Hipóxia , Fenótipo , Proteína do X Frágil da Deficiência Intelectual
8.
Brief Bioinform ; 24(6)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833842

RESUMO

Recent studies have shed light on the potential of circular RNA (circRNA) as a biomarker for disease diagnosis and as a nucleic acid vaccine. The exploration of these functionalities requires correct circRNA full-length sequences; however, existing assembly tools can only correctly assemble some circRNAs, and their performance can be further improved. Here, we introduce a novel feature known as the junction contig (JC), which is an extension of the back-splice junction (BSJ). Leveraging the strengths of both BSJ and JC, we present a novel method called JCcirc (https://github.com/cbbzhang/JCcirc). It enables efficient reconstruction of all types of circRNA full-length sequences and their alternative isoforms using splice graphs and fragment coverage. Our findings demonstrate the superiority of JCcirc over existing methods on human simulation datasets, and its average F1 score surpasses CircAST by 0.40 and outperforms both CIRI-full and circRNAfull by 0.13. For circRNAs below 400 bp, 400-800 bp, 800 bp-1200 bp and above 1200 bp, the correct assembly rates are 0.13, 0.09, 0.04 and 0.03 higher, respectively, than those achieved by existing methods. Moreover, JCcirc also outperforms existing assembly tools on other five model species datasets and real sequencing datasets. These results show that JCcirc is a robust tool for accurately assembling circRNA full-length sequences, laying the foundation for the functional analysis of circRNAs.


Assuntos
RNA Circular , RNA , Humanos , RNA Circular/genética , Análise de Sequência de RNA/métodos , Isoformas de Proteínas/genética , RNA/genética
9.
J Immunol ; 211(6): 964-980, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37578390

RESUMO

Teleost B cells are primitive lymphocytes with both innate and adaptive immune functions. However, the heterogeneity and differentiation trajectory of teleost B cells remain largely unknown. In this study, the landscape of grass carp IgM+ (gcIgM+) B cells was revealed by single-cell RNA sequencing. The results showed that gcIgM+ B cells mainly comprise six populations: (im)mature B cells, innate B cells, proliferating B cells, plasma cells, CD22+ cells, and CD34+ cells, among which innate B cells and proliferating B cells were uncommon B cell subsets with, to our knowledge, new characteristics. Remarkably, three functional IgMs were discovered in grass carp, and a significant percentage of gcIgM+ B cells, especially plasma cells, expressed multiple Igµ genes (Igµ1, Igµ2, and/or Igµ3). More importantly, through single-cell sorting combined with Sanger sequencing, we found that distinct VHDJH recombination patterns of Igµ genes were present in single IgM+ B cells, indicating that individual teleost B cells might produce multiple Abs by coexpressing rearranged IgM subclass genes. Moreover, the percentage of IgM1highIgM2highIgM3high plasma cells increased significantly after bacterial infection, suggesting that individual plasma cells might tend to produce multiple IgMs to resist the infection in teleost fish. In summary, to our knowledge, this study not only helps to uncover the unique heterogeneity of B cells in early vertebrates but also provided significant new evidence supporting the recently proposed "one cell-multiple Abs" paradigm, challenging the classical rule of "one cell-one Ab."


Assuntos
Infecções Bacterianas , Carpas , Doenças dos Peixes , Animais , Imunidade Inata/genética , Proteínas de Peixes/genética , Imunoglobulina M , Homeostase
10.
J Infect Dis ; 229(6): 1791-1795, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38134382

RESUMO

Vaginal inserts that can be used on demand before or after sex may be a desirable human immunodeficiency virus (HIV) prevention option for women. We recently showed that inserts containing tenofovir alafenamide fumarate (TAF, 20 mg) and elvitegravir (EVG, 16 mg) were highly protective against repeated simian/human immunodeficiency virus (SHIV) vaginal exposures when administered to macaques 4 hours before or after virus exposure (93% and 100%, respectively). Here, we show in the same macaque model that insert application 8 hours or 24 hours after exposure maintains high efficacy (94.4% and 77.2%, respectively). These data extend the protective window by TAF/EVG inserts and inform their clinical development for on-demand prophylaxis in women.


Assuntos
Adenina , Alanina , Fármacos Anti-HIV , Quinolonas , Síndrome de Imunodeficiência Adquirida dos Símios , Tenofovir , Animais , Tenofovir/administração & dosagem , Tenofovir/análogos & derivados , Feminino , Quinolonas/administração & dosagem , Quinolonas/farmacologia , Alanina/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Fármacos Anti-HIV/administração & dosagem , Adenina/análogos & derivados , Adenina/administração & dosagem , Adenina/farmacologia , Adenina/uso terapêutico , Vagina/virologia , Vagina/efeitos dos fármacos , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Administração Intravaginal , Macaca mulatta , Modelos Animais de Doenças
11.
Mol Biol Evol ; 40(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37341536

RESUMO

Three prevalent SARS-CoV-2 variants of concern (VOCs) emerged and caused epidemic waves. It is essential to uncover advantageous mutations that cause the high transmissibility of VOCs. However, viral mutations are tightly linked, so traditional population genetic methods, including machine learning-based methods, cannot reliably detect mutations conferring a fitness advantage. In this study, we developed an approach based on the sequential occurrence order of mutations and the accelerated furcation rate in the pandemic-scale phylogenomic tree. We analyzed 3,777,753 high-quality SARS-CoV-2 genomic sequences and the epidemiology metadata using the Coronavirus GenBrowser. We found that two noncoding mutations at the same position (g.a28271-/u) may be crucial to the high transmissibility of Alpha, Delta, and Omicron VOCs although the noncoding mutations alone cannot increase viral transmissibility. Both mutations cause an A-to-U change at the core position -3 of the Kozak sequence of the N gene and significantly reduce the protein expression ratio of ORF9b to N. Using a convergent evolutionary analysis, we found that g.a28271-/u, S:p.P681H/R, and N:p.R203K/M occur independently on three VOC lineages, suggesting that coordinated changes of S, N, and ORF9b proteins are crucial to high viral transmissibility. Our results provide new insights into high viral transmissibility co-modulated by advantageous noncoding and nonsynonymous changes.


Assuntos
COVID-19 , COVID-19/genética , SARS-CoV-2/genética , Evolução Biológica , Mutação , Pandemias
12.
Lancet ; 401(10380): 917-927, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36842439

RESUMO

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Masculino , Humanos , Feminino , Carcinoma Nasofaríngeo/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Recidiva Local de Neoplasia/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Hemorragia
13.
Small ; : e2401834, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623962

RESUMO

Different facets in perovskite crystals exhibit distinct atomic arrangements, influencing their electronic, physical, and chemical properties. Perovskite films incorporating tin oxide (SnO2) as the electron transport layer face challenges in facet regulation. This study reveals that tea saponin (TS), a natural compound serves as a SnO2 modifier, facilitates optimal growth of perovskite crystals on the (111) facet. The modification promotes preferential crystal orientation through hydrogen bond and Lewis coordination. TS forms a chelate with SnO2, resulting in a smoother film and n-type doping, leading to improved carrier extraction and reduced defects. The TS-modified perovskite solar cells achieve a champion efficiency of 24.2%, leveraging from an obvious enhancement of open-circuit voltage (Voc) of 1.18 V and fill factor (FF) of 82.8%. The devices also demonstrate enhanced humidity tolerance and storage stability, ensuring improved stability without encapsulation.

14.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34864877

RESUMO

Increasing evidences have proved that circRNA plays a significant role in the development of many diseases. In addition, many researches have shown that circRNA can be considered as the potential biomarker for clinical diagnosis and treatment of disease. Some computational methods have been proposed to predict circRNA-disease associations. However, the performance of these methods is limited as the sparsity of low-order interaction information. In this paper, we propose a new computational method (KGANCDA) to predict circRNA-disease associations based on knowledge graph attention network. The circRNA-disease knowledge graphs are constructed by collecting multiple relationship data among circRNA, disease, miRNA and lncRNA. Then, the knowledge graph attention network is designed to obtain embeddings of each entity by distinguishing the importance of information from neighbors. Besides the low-order neighbor information, it can also capture high-order neighbor information from multisource associations, which alleviates the problem of data sparsity. Finally, the multilayer perceptron is applied to predict the affinity score of circRNA-disease associations based on the embeddings of circRNA and disease. The experiment results show that KGANCDA outperforms than other state-of-the-art methods in 5-fold cross validation. Furthermore, the case study demonstrates that KGANCDA is an effective tool to predict potential circRNA-disease associations.


Assuntos
MicroRNAs , RNA Circular , Biologia Computacional/métodos , MicroRNAs/genética , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão
15.
Brief Bioinform ; 23(2)2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35043153

RESUMO

Genomic epidemiology is important to study the COVID-19 pandemic, and more than two million severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomic sequences were deposited into public databases. However, the exponential increase of sequences invokes unprecedented bioinformatic challenges. Here, we present the Coronavirus GenBrowser (CGB) based on a highly efficient analysis framework and a node-picking rendering strategy. In total, 1,002,739 high-quality genomic sequences with the transmission-related metadata were analyzed and visualized. The size of the core data file is only 12.20 MB, highly efficient for clean data sharing. Quick visualization modules and rich interactive operations are provided to explore the annotated SARS-CoV-2 evolutionary tree. CGB binary nomenclature is proposed to name each internal lineage. The pre-analyzed data can be filtered out according to the user-defined criteria to explore the transmission of SARS-CoV-2. Different evolutionary analyses can also be easily performed, such as the detection of accelerated evolution and ongoing positive selection. Moreover, the 75 genomic spots conserved in SARS-CoV-2 but non-conserved in other coronaviruses were identified, which may indicate the functional elements specifically important for SARS-CoV-2. The CGB was written in Java and JavaScript. It not only enables users who have no programming skills to analyze millions of genomic sequences, but also offers a panoramic vision of the transmission and evolution of SARS-CoV-2.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Vigilância em Saúde Pública/métodos , SARS-CoV-2/genética , Software , Navegador , Biologia Computacional/métodos , Análise Mutacional de DNA , Bases de Dados Genéticas , Genoma Viral , Genômica , Humanos , Epidemiologia Molecular/métodos , Anotação de Sequência Molecular , Mutação
16.
BMC Microbiol ; 24(1): 156, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724913

RESUMO

BACKGROUND: To establish a method to induce Campylobacter jejuni colonization in the intestines of C57BL/6 mice through antibiotic-induced microbiome depletion. RESULTS: Fifty-four female C57BL/6 mice were divided into the normal, control, and experimental groups. The experimental group was administered intragastric cefoperazone sodium and sulbactam sodium (50 mg/mL) for 2 days; then, the experimental and control mice were intragastrically administered 200 µL C. jejuni, which was repeated once more after 2 days. Animal feces were collected, and the HipO gene of C. jejuni was detected using TaqMan qPCR from day 1 to day 14 after modeling completion. Immunofluorescence was used to detect intestinal C. jejuni colonization on day 14, and pathological changes were observed using hematoxylin and eosin staining. Additionally, 16S rDNA analyses of the intestinal contents were conducted on day 14. In the experimental group, C. jejuni was detected in the feces from days 1 to 14 on TaqMan qPCR, and immunofluorescence-labeled C. jejuni were visibly discernable in the intestinal lumen. The intestinal mucosa was generally intact and showed no significant inflammatory-cell infiltration. Diversity analysis of the colonic microbiota showed significant inter-group differences. In the experimental group, the composition of the colonic microbiota differed from that in the other 2 groups at the phylum level, and was characterized by a higher proportion of Bacteroidetes and a lower proportion of Firmicutes. CONCLUSIONS: Microbiome depletion induced by cefoperazone sodium and sulbactam sodium could promote long-term colonization of C. jejuni in the intestines of mice.


Assuntos
Antibacterianos , Infecções por Campylobacter , Campylobacter jejuni , Cefoperazona , Fezes , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , RNA Ribossômico 16S , Sulbactam , Animais , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/crescimento & desenvolvimento , Feminino , Antibacterianos/farmacologia , Cefoperazona/farmacologia , Fezes/microbiologia , Infecções por Campylobacter/microbiologia , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Sulbactam/farmacologia , RNA Ribossômico 16S/genética , Intestinos/microbiologia , Colo/microbiologia , Colo/patologia , Modelos Animais de Doenças , Mucosa Intestinal/microbiologia , Mucosa Intestinal/efeitos dos fármacos , DNA Bacteriano/genética , DNA Ribossômico/genética
17.
J Exp Bot ; 75(10): 3153-3170, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38394357

RESUMO

Endophytic symbioses between plants and fungi are a dominant feature of many terrestrial ecosystems, yet little is known about the signaling that defines these symbiotic associations. Hydrogen peroxide (H2O2) is recognized as a key signal mediating the plant adaptive response to both biotic and abiotic stresses. However, the role of H2O2 in plant-fungal symbiosis remains elusive. Using a combination of physiological analysis, plant and fungal deletion mutants, and comparative transcriptomics, we reported that various environmental conditions differentially affect the interaction between Arabidopsis and the root endophyte Phomopsis liquidambaris, and link this process to alterations in H2O2 levels and H2O2 fluxes across root tips. We found that enhanced H2O2 efflux leading to a moderate increase in H2O2 levels at the plant-fungal interface is required for maintaining plant-fungal symbiosis. Disturbance of plant H2O2 homeostasis compromises the symbiotic ability of plant roots. Moreover, the fungus-regulated H2O2 dynamics modulate the rhizosphere microbiome by selectively enriching for the phylum Cyanobacteria, with strong antioxidant defenses. Our results demonstrated that the regulation of H2O2 dynamics at the plant-fungal interface affects the symbiotic outcome in response to external conditions and highlight the importance of the root endophyte in reshaping the rhizosphere microbiota.


Assuntos
Arabidopsis , Endófitos , Homeostase , Peróxido de Hidrogênio , Microbiota , Raízes de Plantas , Rizosfera , Simbiose , Arabidopsis/microbiologia , Arabidopsis/fisiologia , Endófitos/fisiologia , Peróxido de Hidrogênio/metabolismo , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Ascomicetos/fisiologia
18.
Chemistry ; : e202402231, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008402

RESUMO

Supramolecular polymers (SPs) are constructed through non-covalent interactions. The dynamic or reversible nature of SPs endows them unique physical and chemical properties, such as self-adaptive and stimuli-response abilities. The topological structures of SPs play an important role in determining the physicochemical properties and functionality. Hyperbranched polymers (HBPs) are highly branched 3D macromolecules with linear, dendritic, and terminal units, which makes them versatile candidates for the construction of SPs with fascinating architectures. The resultant HBP-based SPs perfectly integrated the dynamic/reversible nature of SPs and the 3D topological features and multifunctionality of HBP polymers. To date, various types of HBP-based SPs and their assemblies have been constructed, and their potential applications have been explored as well. This article overviews the current progress on self-assembly of HBP-based SPs. The strategies for construction of HBP-based SPs and their assemblies are discussed. Typical potential applications of the assemblies of HBP-based SPs are also introduced.

19.
J Magn Reson Imaging ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609076

RESUMO

BACKGROUND: Lymph node metastasis (LNM) in patients with intrahepatic cholangiocarcinoma (iCCA) affects treatment strategies and prognosis. However, preoperative imaging is not reliable enough for identifying LNM. PURPOSE: To develop and validate a radiomics nomogram based on dynamic contrast enhanced (DCE)-MR images for identifying LNM and prognosis in iCCA. STUDY TYPE: Retrospective. SUBJECTS: Two hundred four patients with pathologically proven iCCA who underwent curative-intent resection and lymphadenectomy (training cohort: N = 107, internal test cohort: N = 46, and external test cohort: N = 51). FIELD STRENGTH/SEQUENCE: T1- and T2-weighted imaging, diffusion-weighted imaging and DCE imaging at 1.5 T or 3.0 T. ASSESSMENT: Radiomics features were extracted from intra- and peri-tumoral regions on preoperative DCE-MR images. Imaging features were evaluated by three radiologists, and significant variables in univariable and multivariable regression analysis were included in clinical model. The best-performing radiomics signature and clinical characteristics (intrahepatic duct dilatation, MRI-reported LNM) were combined to build a nomogram. Patients were divided into high-risk and low-risk groups based on their nomogram scores (cutoff = 0.341). Patients were followed up for 1-102 months (median 12) after surgery, the overall survival (OS) and recurrence-free survival (RFS) were calculated. STATISTICAL TESTS: Receiver operating characteristic (ROC) curve, calibration, decision curve, Delong test, Kaplan-Meier curves, log rank test. Two tailed P < 0.05 was considered statistically significant. RESULTS: The nomogram incorporating intra- and peri-tumoral radiomics features, intrahepatic duct dilatation and MRI-reported LNM obtained the best discrimination for LNM, with areas under the ROC curves of 0.946, 0.913, and 0.859 in the training, internal, and external test cohorts. In the entire cohort, high-risk patients had significantly lower RFS and OS than low-risk patients. High-risk of LNM was an independent factor of unfavorable OS and RFS. DATA CONCLUSION: The nomogram integrating intra- and peri-tumoral radiomics signatures has potential to identify LNM and prognosis in iCCA. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

20.
Nutr Cancer ; 76(6): 486-498, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680010

RESUMO

Serum Cytokines Correlate with Pretreatment Body Mass Index-Adjusted Body Weight Loss Grading and Cancer Progression in Patients with Stage III Esophageal Squamous Cell Carcinoma Undergoing Neoadjuvant Chemoradiotherapy Followed by Surgery. Circulating cytokines have been linked to the development of esophageal squamous cell carcinoma (ESCC) and its associated malnutrition process. Nonetheless, given the varied disease stages and treatment modalities in previous studies, the clinical relevance of their findings is limited. We retrospectively studied 52 patients with stage III ESCC who underwent neoadjuvant chemoradiotherapy and curative-intent surgery. We investigated the association of clinicopathological features, pretreatment laboratory data, and pretreatment inflammatory status, as indicated by the levels of albumin, C-reactive protein, and 10 circulating cytokines, namely tumor necrosis factor-alpha (TNF-α), interferon-gamma, interleukin-1-beta (IL-1ß), IL-4, IL-6, IL-8, IL-12, IL-13, IL-17A, and IL-23, with malnutrition, as shown by body mass index-adjusted body weight loss (BMI-BWL) grading, cancer progression. Half the patients showed severe malnutrition and high BMI-BWL grades (3 and 4). Multivariate analysis revealed an independent association between the levels of three cytokines (TNF-α, ≤ 5.8 pg/ml; IL-1ß, > 0.4 pg/ml; IL-6, ≤ 12.4 pg/ml) and high BMI-BWL grades and between IL-4 levels > 22.5 pg/ml and cancer progression. All 10 cytokines were closely correlated with each other. In conclusion, TNF-α, IL-1ß, and IL-6 were independent markers of malnutrition status and IL-4 was a prognostic factor for cancer progression in this patient population.


Assuntos
Índice de Massa Corporal , Citocinas , Progressão da Doença , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Terapia Neoadjuvante , Redução de Peso , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Citocinas/sangue , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/sangue , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/patologia , Estudos Retrospectivos , Idoso , Terapia Neoadjuvante/métodos , Desnutrição/sangue , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/patologia , Estadiamento de Neoplasias , Quimiorradioterapia/métodos , Fator de Necrose Tumoral alfa/sangue
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