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1.
Immunity ; 46(5): 818-834.e4, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28514688

RESUMO

Innate and adaptive lymphoid development is orchestrated by the activities of E proteins and their antagonist Id proteins, but how these factors regulate early T cell progenitor (ETP) and innate lymphoid cell (ILC) development remains unclear. Using multiple genetic strategies, we demonstrated that E proteins E2A and HEB acted in synergy in the thymus to establish T cell identity and to suppress the aberrant development of ILCs, including ILC2s and lymphoid-tissue-inducer-like cells. E2A and HEB orchestrated T cell fate and suppressed the ILC transcription signature by activating the expression of genes associated with Notch receptors, T cell receptor (TCR) assembly, and TCR-mediated signaling. E2A and HEB acted in ETPs to establish and maintain a T-cell-lineage-specific enhancer repertoire, including regulatory elements associated with the Notch1, Rag1, and Rag2 loci. On the basis of these and previous observations, we propose that the E-Id protein axis specifies innate and adaptive lymphoid cell fate.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Imunomodulação , Subpopulações de Linfócitos/imunologia , Timócitos/imunologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/imunologia , Análise por Conglomerados , Expressão Gênica , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Imunofenotipagem , Proteína 2 Inibidora de Diferenciação/genética , Proteína 2 Inibidora de Diferenciação/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/citologia , Subpopulações de Linfócitos/metabolismo , Células Progenitoras Linfoides/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Timócitos/citologia , Timócitos/metabolismo , Transcriptoma
2.
Nucleic Acids Res ; 51(21): 11927-11940, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37870446

RESUMO

In various autoimmune diseases, dysfunctional TREX1 (Three prime Repair Exonuclease 1) leads to accumulation of endogenous single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and DNA/RNA hybrids in the cytoplasm and triggers immune activation through the cGAS-STING pathway. Although inhibition of TREX1 could be a useful strategy for cancer immunotherapy, profiling cellular functions in terms of its potential substrates is a key step. Particularly important is the functionality of processing DNA/RNA hybrids and RNA substrates. The exonuclease activity measurements conducted here establish that TREX1 can digest both ssRNA and DNA/RNA hybrids but not dsRNA. The newly solved structures of TREX1-RNA product and TREX1-nucleotide complexes show that 2'-OH does not impose steric hindrance or specific interactions for the recognition of RNA. Through all-atom molecular dynamics simulations, we illustrate that the 2'-OH-mediated intra-chain hydrogen bonding in RNA would affect the binding with TREX1 and thereby reduce the exonuclease activity. This notion of higher conformational rigidity in RNA leading TREX1 to exhibit weaker catalytic cleavage is further validated by the binding affinity measurements with various synthetic DNA-RNA junctions. The results of this work thus provide new insights into the mechanism by which TREX1 processes RNA and DNA/RNA hybrids and contribute to the molecular-level understanding of the complex cellular functions of TREX1 as an exonuclease.


Assuntos
DNA , RNA , DNA/genética , DNA/metabolismo , DNA de Cadeia Simples/genética , Exodesoxirribonucleases/metabolismo , Fosfoproteínas/metabolismo , RNA/genética , Animais , Camundongos
3.
Nat Immunol ; 13(12): 1196-204, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23064439

RESUMO

The genome is folded into domains located in compartments that are either transcriptionally inert or transcriptionally permissive. Here we used genome-wide strategies to characterize domains during B cell development. Structured interaction matrix analysis showed that occupancy by the architectural protein CTCF was associated mainly with intradomain interactions, whereas sites bound by the histone acetyltransferase p300 or the transcription factors E2A or PU.1 were associated with intra- and interdomain interactions that are developmentally regulated. We identified a spectrum of genes that switched nuclear location during early B cell development. In progenitor cells, the transcriptionally inactive locus encoding early B cell factor (Ebf1) was sequestered at the nuclear lamina, which thereby preserved their multipotency. After development into the pro-B cell stage, Ebf1 and other genes switched compartments to establish new intra- and interdomain interactions associated with a B lineage-specific transcription signature.


Assuntos
Linfócitos B/fisiologia , Linhagem da Célula , Núcleo Celular/genética , Linfopoese , Células Precursoras de Linfócitos B/fisiologia , Animais , Linfócitos B/citologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fator de Ligação a CCCTC , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Camundongos Endogâmicos C57BL , Lâmina Nuclear/metabolismo , Células Precursoras de Linfócitos B/citologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Transativadores/genética , Transativadores/metabolismo , Transcrição Gênica , Fatores de Transcrição de p300-CBP/genética
4.
Mol Psychiatry ; 28(9): 3955-3965, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37798418

RESUMO

Diabetic patients receiving the antidiabetic drug metformin have been observed to exhibit a lower prevalence of anxiety disorders, yet the precise mechanism behind this phenomenon is unclear. In our study, we found that anxiety induces a region-specific reduction in AMPK activity in the medial prefrontal cortex (mPFC). Concurrently, transgenic mice with brain-specific AMPK knockout displayed abnormal anxiety-like behaviors. Treatment with metformin or the overexpression of AMPK restored normal AMPK activity in the mPFC and mitigated social stress-induced anxiety-like behaviors. Furthermore, the specific genetic deletion of AMPK in the mPFC not only instigated anxiety in mice but also nullified the anxiolytic effects of metformin. Brain slice recordings revealed that GABAergic excitation and the resulting inhibitory inputs to mPFC pyramidal neurons were selectively diminished in stressed mice. This reduction led to an excitation-inhibition imbalance, which was effectively reversed by metformin treatment or AMPK overexpression. Moreover, the genetic deletion of AMPK in the mPFC resulted in a similar defect in GABAergic inhibitory transmission and a consequent hypo-inhibition of mPFC pyramidal neurons. We also generated a mouse model with AMPK knockout specific to GABAergic neurons. The anxiety-like behaviors in this transgenic mouse demonstrated the unique role of AMPK in the GABAergic system in relation to anxiety. Therefore, our findings suggest that the activation of AMPK in mPFC inhibitory neurons underlies the anxiolytic effects of metformin, highlighting the potential of this primary antidiabetic drug as a therapeutic option for treating anxiety disorders.


Assuntos
Ansiolíticos , Metformina , Humanos , Camundongos , Animais , Ansiolíticos/farmacologia , Proteínas Quinases Ativadas por AMP/farmacologia , Metformina/farmacologia , Hipoglicemiantes/farmacologia , Córtex Pré-Frontal , Neurônios GABAérgicos
5.
Immunity ; 42(2): 239-251, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25692700

RESUMO

T follicular helper (Tfh) cells are essential in the induction of high-affinity, class-switched antibodies. The differentiation of Tfh cells is a multi-step process that depends upon the co-receptor ICOS and the activation of phosphoinositide-3 kinase leading to the expression of key Tfh cell genes. We report that ICOS signaling inactivates the transcription factor FOXO1, and a Foxo1 genetic deletion allowed for generation of Tfh cells with reduced dependence on ICOS ligand. Conversely, enforced nuclear localization of FOXO1 inhibited Tfh cell development even though ICOS was overexpressed. FOXO1 regulated Tfh cell differentiation through a broad program of gene expression exemplified by its negative regulation of Bcl6. Final differentiation to germinal center Tfh cells (GC-Tfh) was instead FOXO1 dependent as the Foxo1(-/-) GC-Tfh cell population was substantially reduced. We propose that ICOS signaling transiently inactivates FOXO1 to initiate a Tfh cell contingency that is completed in a FOXO1-dependent manner.


Assuntos
Diferenciação Celular/imunologia , Proteínas de Ligação a DNA/biossíntese , Fatores de Transcrição Forkhead/genética , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Linfócitos T Auxiliares-Indutores/citologia , Animais , Ativação Enzimática , Proteína Forkhead Box O1 , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6 , Transdução de Sinais , Linfócitos T Auxiliares-Indutores/imunologia
6.
Pediatr Allergy Immunol ; 35(5): e14143, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38745384

RESUMO

BACKGROUND: Childhood allergies of asthma and atopic dermatitis (AD) involve an overactive T-cell immune response triggered by allergens. However, the impact of T-cell receptor (TCR) repertoires on allergen sensitization and their role in mediating different phenotypes of asthma and AD in early childhood remains unclear. METHODS: A total of 78 children, comprising 26 with asthma alone, 26 with AD alone, and 26 healthy controls (HC), were enrolled. TCR repertoire profiles were determined using a unique molecular identifier system for next-generation sequencing. Integrative analyses of their associations with allergen-specific IgE levels and allergies were performed. RESULTS: The diversity in TCR alpha variable region (TRAV) genes of TCR repertoires and complementarity determining region 3 (CDR3) clonality in TRAV/TRBV (beta) genes were significantly higher in children with AD compared with those with asthma and HC (p < .05). Compared with HC, the expression of TRAV13-1 and TRAV4 genes was significantly higher in both asthma and AD (p < .05), with a significant positive correlation with mite-specific IgE levels (p < .01). In contrast, TRBV7-9 gene expression was significantly lower in both asthma and AD (p < .01), with this gene showing a significant negative correlation with mite-specific IgE levels (p < .01). Furthermore, significantly higher TRAV8-3 gene expression, positively correlated with food-specific IgE levels, was found in children with AD compared with those with asthma (p < .05). CONCLUSION: Integrated TCR repertoires analysis provides clinical insights into the diverse TCR genes linked to antigen specificity, offering potential for precision immunotherapy in childhood allergies.


Assuntos
Alérgenos , Asma , Dermatite Atópica , Imunoglobulina E , Humanos , Asma/imunologia , Asma/genética , Dermatite Atópica/imunologia , Dermatite Atópica/genética , Masculino , Feminino , Alérgenos/imunologia , Criança , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Pré-Escolar , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/imunologia , Estudos de Casos e Controles , Animais
7.
Acta Pharmacol Sin ; 45(1): 36-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37684382

RESUMO

The gut-brain axis plays a vital role in Parkinson's disease (PD). The mechanisms of gut-brain transmission mainly focus on α-synuclein deposition, intestinal inflammation and microbiota function. A few studies have shown the trigger of PD pathology in the gut. α-Synuclein is highly conserved in food products, which was able to form ß-folded aggregates and to infect the intestinal mucosa. In this study we investigated whether α-synuclein-preformed fibril (PFF) exposure could modulate the intestinal environment and induce rodent models replicating PD pathology. We first showed that PFF could be internalized into co-cultured Caco-2/HT29/Raji b cells in vitro. Furthermore, we demonstrated that PFF perfusion caused the intestinal inflammation and activation of enteric glial cells in an ex vivo intestinal organ culture and in an in vivo intestinal mouse coloclysis model. Moreover, we found that PFF exposure through regular coloclysis induced PD pathology in wild-type (WT) and A53T α-synuclein transgenic mice with various phenotypes. Particularly in A53T mice, PFF induced significant behavioral disorders, intestinal inflammation, α-synuclein deposition, microbiota dysbiosis, glial activation as well as degeneration of dopaminergic neurons in the substantia nigra. In WT mice, however, the PFF induced only mild behavioral abnormalities, intestinal inflammation, α-synuclein deposition, and glial activation, without significant changes in microbiota and dopaminergic neurons. Our results reveal the possibility of α-synuclein aggregates binding to the intestinal mucosa and modeling PD in mice. This study may shed light on the investigation and early intervention of the gut-origin hypothesis in neurodegenerative diseases.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Camundongos , Animais , alfa-Sinucleína/metabolismo , Células CACO-2 , Transtornos Parkinsonianos/metabolismo , Doença de Parkinson/metabolismo , Camundongos Transgênicos , Neurônios Dopaminérgicos/metabolismo , Inflamação/metabolismo
8.
Int J Med Sci ; 21(8): 1559-1574, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903921

RESUMO

Background: PtdIns (3,4,5) P3-dependent Rac exchanger 1 (PREX1), also known as PREX1, a member of the Rac guanine nucleotide exchange factors (Rac-GEF) family. Studies have suggested that PREX1 plays a role in mediating oncogenic pathway activation and controlling various biological mechanisms in different types of cancer, including liver hepatocellular carcinoma (LIHC). However, the function of PREX1 in the pathogenesis of LIHC and its potential role on immunological regulation is not clearly elucidated. Methods: The expression level and the clinical role of PREX1 in LIHC was analyzed based on database from the Cancer Genome Atlas (TCGA), TNM plotter and University of Alabama Cancer Database (UALCAN). We investigated the relationship between PREX1 and immunity in LIHC by TISIDB, CIBERSORT and single cell analysis. Immunotherapy responses were assessed by the immunophenoscores (IPS). Moreover, biological functional assays were performed to further investigate the roles of PREX1 in liver cancer cell lines. Results: Higher expression of PREX1 in LIHC tissues than in normal liver tissues was found based on public datasets. Further analysis revealed that PREX1 was associated with worse clinical characteristics and dismal prognosis. Pathway enrichment analysis indicated that PREX1 participated in immune-related pathways. Through CIBERSORT and single cell analysis, we found a remarkable correlation between the expression of PREX1 and various immune cells, especially macrophages. In addition, high PREX1 expression was found to be associated with a stronger response to immunotherapy. Furthermore, in vitro assays indicated that depletion of PREX1 can suppress invasion and proliferation of LIHC cells. Conclusion: Elevated expression of PREX1 indicates poor prognosis, influences immune modulation and predicts sensitivity of immunosuppression therapy in LIHC. Our results suggested that PREX1 may be a prognostic biomarker and therapeutic target, offering new treatment options for LIHC.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , Análise de Célula Única , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Prognóstico , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Linhagem Celular Tumoral , Fatores de Troca do Nucleotídeo Guanina/genética , Masculino , Transcriptoma/imunologia , Transcriptoma/genética , Proteínas de Transferência de Fosfolipídeos/genética , Proteínas de Transferência de Fosfolipídeos/metabolismo , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Feminino
9.
Nucleic Acids Res ; 50(W1): W616-W622, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35536289

RESUMO

With the proliferation of genomic sequence data for biomedical research, the exploration of human genetic information by domain experts requires a comprehensive interrogation of large numbers of scientific publications in PubMed. However, a query in PubMed essentially provides search results sorted only by the date of publication. A search engine for retrieving and interpreting complex relations between biomedical concepts in scientific publications remains lacking. Here, we present pubmedKB, a web server designed to extract and visualize semantic relationships between four biomedical entity types: variants, genes, diseases, and chemicals. pubmedKB uses state-of-the-art natural language processing techniques to extract semantic relations from the large number of PubMed abstracts. Currently, over 2 million semantic relations between biomedical entity pairs are extracted from over 33 million PubMed abstracts in pubmedKB. pubmedKB has a user-friendly interface with an interactive semantic graph, enabling the user to easily query entities and explore entity relations. Supporting sentences with the highlighted snippets allow to easily navigate the publications. Combined with a new explorative approach to literature mining and an interactive interface for researchers, pubmedKB thus enables rapid, intelligent searching of the large biomedical literature to provide useful knowledge and insights. pubmedKB is available at https://www.pubmedkb.cc/.


Assuntos
Computadores , Ferramenta de Busca , Humanos , PubMed , Semântica , Mineração de Dados/métodos
10.
BMC Med Inform Decis Mak ; 24(1): 118, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702739

RESUMO

BACKGROUND: Pneumonia poses a major global health challenge, necessitating accurate severity assessment tools. However, conventional scoring systems such as CURB-65 have inherent limitations. Machine learning (ML) offers a promising approach for prediction. We previously introduced the Blood Culture Prediction Index (BCPI) model, leveraging solely on complete blood count (CBC) and differential leukocyte count (DC), demonstrating its effectiveness in predicting bacteremia. Nevertheless, its potential in assessing pneumonia remains unexplored. Therefore, this study aims to compare the effectiveness of BCPI and CURB-65 in assessing pneumonia severity in an emergency department (ED) setting and develop an integrated ML model to enhance efficiency. METHODS: This retrospective study was conducted at a 3400-bed tertiary medical center in Taiwan. Data from 9,352 patients with pneumonia in the ED between 2019 and 2021 were analyzed in this study. We utilized the BCPI model, which was trained on CBC/DC data, and computed CURB-65 scores for each patient to compare their prognosis prediction capabilities. Subsequently, we developed a novel Cox regression model to predict in-hospital mortality, integrating the BCPI model and CURB-65 scores, aiming to assess whether this integration enhances predictive performance. RESULTS: The predictive performance of the BCPI model and CURB-65 score for the 30-day mortality rate in ED patients and the in-hospital mortality rate among admitted patients was comparable across all risk categories. However, the Cox regression model demonstrated an improved area under the ROC curve (AUC) of 0.713 than that of CURB-65 (0.668) for in-hospital mortality (p<0.001). In the lowest risk group (CURB-65=0), the Cox regression model outperformed CURB-65, with a significantly lower mortality rate (2.9% vs. 7.7%, p<0.001). CONCLUSIONS: The BCPI model, constructed using CBC/DC data and ML techniques, performs comparably to the widely utilized CURB-65 in predicting outcomes for patients with pneumonia in the ED. Furthermore, by integrating the CURB-65 score and BCPI model into a Cox regression model, we demonstrated improved prediction capabilities, particularly for low-risk patients. Given its simple parameters and easy training process, the Cox regression model may be a more effective prediction tool for classifying patients with pneumonia in the emergency room.


Assuntos
Serviço Hospitalar de Emergência , Aprendizado de Máquina , Pneumonia , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Pneumonia/diagnóstico , Prognóstico , Contagem de Leucócitos , Taiwan , Contagem de Células Sanguíneas , Mortalidade Hospitalar , Idoso de 80 Anos ou mais , Adulto
11.
Br J Haematol ; 202(6): 1119-1126, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37434414

RESUMO

To reducing chemotherapy-related toxicity, the chemo-free regimens become a new trend of Ph + ALL treatment. Therefore, we conducted a phase 2 trial of dasatinib plus prednisone, as induction (Course I) and early consolidation (Courses II and III) treating newly diagnosed Ph + ALL. The trial was registered at www.chictr.org.cn, ChiCTR2000038053. Forty-one patients were enrolled from 15 hospitals. The complete remission (CR) was 95% (39/41), including two elderly induction deaths. By the end of Course III, 25.6% (10/39) of patients achieved a complete molecular response. With a median follow-up of 15.4 months, 2-year disease-free survival (DFS) were 100% and 33% for patients who receiving haematopoietic stem cell transplantation (HSCT) at CR1 and receiving chemotherapy alone respectively. When censored at time of HSCT, 2-year DFS were 51% and 45% for young and elderly patients (p = 0.987). 2-year overall survival were 45%, 86% and 100% for patients without HSCT, receiving HSCT after relapse and receiving HSCT at CR1 respectively. A total of 12 patients had marrow recurrences and one had CNS relapse, with 38% occurred early (between Courses I and III). IKZF1 gene deletion was shown to be associated with relapse (p = 0.019). This chemo-free induction and early consolidation regimen was efficacious and well-tolerated in de novo Ph + ALL. Allogeneic HSCT conferred definite survival advantage after chemo-free induction.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Adulto , Idoso , Dasatinibe/efeitos adversos , Prednisona/efeitos adversos , Cromossomo Filadélfia , Recidiva Local de Neoplasia/tratamento farmacológico , Intervalo Livre de Doença , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Indução de Remissão , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
12.
PLoS Pathog ; 17(8): e1009758, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34379705

RESUMO

Since the pandemic of COVID-19 has intensely struck human society, small animal model for this infectious disease is in urgent need for basic and pharmaceutical research. Although several COVID-19 animal models have been identified, many of them show either minimal or inadequate pathophysiology after SARS-CoV-2 challenge. Here, we describe a new and versatile strategy to rapidly establish a mouse model for emerging infectious diseases in one month by multi-route, multi-serotype transduction with recombinant adeno-associated virus (AAV) vectors expressing viral receptor. In this study, the proposed approach enables profound and enduring systemic expression of SARS-CoV-2-receptor hACE2 in wild-type mice and renders them vulnerable to SARS-CoV-2 infection. Upon virus challenge, generated AAV/hACE2 mice showed pathophysiology closely mimicking the patients with severe COVID-19. The efficacy of a novel therapeutic antibody cocktail RBD-chAbs for COVID-19 was tested and confirmed by using this AAV/hACE2 mouse model, further demonstrating its successful application in drug development.


Assuntos
COVID-19 , Doenças Transmissíveis Emergentes , Modelos Animais de Doenças , Células 3T3 , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , COVID-19/imunologia , COVID-19/patologia , COVID-19/fisiopatologia , Chlorocebus aethiops , Dependovirus/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transdução Genética , Células Vero
13.
Nat Immunol ; 12(10): 992-1001, 2011 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21857655

RESUMO

It is established that the transcription factor E2A and its antagonist Id3 modulate the checkpoints consisting of the precursor to the T cell antigen receptor (pre-TCR) and the TCR. Here we demonstrate that Id3 expression was higher beyond the pre-TCR checkpoint, remained high in naive T cells and showed a bimodal pattern in the effector-memory population. We show how E2A promoted T lineage specification and how pre-TCR-mediated signaling affected E2A genome-wide occupancy. Thymi in Id3-deficient mice had aberrant development of effector-memory cells, higher expression of the chemokine receptor CXCR5 and the transcriptional repressor Bcl-6 and, unexpectedly, T cell-B cell conjugates and B cell follicles. Collectively, our data show how E2A acted globally to orchestrate development into the T lineage and that Id3 antagonized E2A activity beyond the pre-TCR checkpoint to enforce the naive fate of T cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Proteínas Inibidoras de Diferenciação/fisiologia , Linfócitos T/imunologia , Animais , Memória Imunológica , Imunofenotipagem , Antígenos Comuns de Leucócito/análise , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T/fisiologia , Receptores CXCR5/análise , Baço/imunologia , Timo/imunologia
14.
Acta Pharmacol Sin ; 44(6): 1122-1134, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36627343

RESUMO

Aggregation of α-synuclein, a component of Lewy bodies (LBs) or Lewy neurites in Parkinson's disease (PD), is strongly linked with disease development, making it an attractive therapeutic target. Inhibiting aggregation can slow or prevent the neurodegenerative process. However, the bottleneck towards achieving this goal is the lack of such inhibitors. In the current study, we established a high-throughput screening platform to identify candidate compounds for preventing the aggregation of α-synuclein among the natural products in our in-house compound library. We found that a small molecule, 03A10, i.e., (+)-desdimethylpinoresinol, which is present in the fruits of Vernicia fordii (Euphorbiaceae), modulated aggregated α-synuclein, but not monomeric α-synuclein, to prevent further elongation of α-synuclein fibrils. In α-synuclein-overexpressing cell lines, 03A10 (10 µM) efficiently prevented α-synuclein aggregation and markedly ameliorated the cellular toxicity of α-synuclein fibril seeds. In the MPTP/probenecid (MPTP/p) mouse model, oral administration of 03A10 (0.3 mg· kg-1 ·d-1, 1 mg ·kg-1 ·d-1, for 35 days) significantly alleviated behavioral deficits, tyrosine hydroxylase (TH) neuron degeneration and p-α-synuclein aggregation in the substantia nigra (SN). As the Braak hypothesis postulates that the prevailing site of early PD pathology is the gastrointestinal tract, we inoculated α-synuclein preformed fibrils (PFFs) into the mouse colon. We demonstrated that α-synuclein PFF inoculation promoted α-synuclein pathology and neuroinflammation in the gut and brain; oral administration of 03A10 (5 mg· kg-1 ·d-1, for 4 months) significantly attenuated olfactory deficits, α-synuclein accumulation and neuroinflammation in the olfactory bulb and SN. We conclude that 03A10 might be a promising drug candidate for the treatment of PD. 03A10 might be a novel drug candidate for PD treatment, as it inhibits α-synuclein aggregation by modulating aggregated α-synuclein rather than monomeric α-synuclein to prevent further elongation of α-synuclein fibrils and prevent α-synuclein toxicity in vitro, in an MPTP/p mouse model, and PFF-inoculated mice.


Assuntos
Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Doenças Neuroinflamatórias , Substância Negra/metabolismo , Substância Negra/patologia , Encéfalo/metabolismo
15.
Neurol Sci ; 44(1): 191-197, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36098886

RESUMO

BACKGROUND: Constipation, rapid eye movement sleep behavior disorder (RBD) and hyposmia are common prodromal symptoms of Parkinson's disease (PD), and they may represent two distinct types of disease origin, from the body or the brain. Our study aimed to compare the clinical characteristics of de novo PD patients with and without constipation and identify which prodromal symptoms were associated with constipation. METHODS: A total of 111 de novo, drug-naïve Chinese PD patients were consecutively enrolled from Jan 2017 to Sept 2021. Patients were classified into PD with and without constipation based on item 5 of the Scales for Outcomes in Parkinson's disease-Autonomic Dysfunction (SCOPA-AUT). The demographic data, motor, and non-motor symptoms were compared between the two groups. The associated factors of constipation were analyzed by the multivariate logistic regression analysis. RESULTS: In total, 44.1% (n = 49) of de novo PD patients had constipation. PD patients with constipation were older (p = 0.028), had higher proportions of Hoehn and Yahr (H-Y) stage [Formula: see text] 2 (p = 0.002), clinical possible RBD (cpRBD) (p = 0.002) and depression (p = 0.023), as well as marginal increase of hyposmia (p = 0.058) and freezing of gait (p = 0.069). After adjusting for H-Y stage and other confounding factors, cpRBD (OR = 3.508, p = 0.009), rather than hyposmia or depression, was closely related to constipation in de novo Chinese PD patients. CONCLUSIONS: RBD is closely associated with constipation in de novo Chinese PD patients. Our results support the theory that prodromal symptoms that represent the same pathological origin are closely related to each other.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Transtorno do Comportamento do Sono REM , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/epidemiologia , Doença de Parkinson/diagnóstico , Transtorno do Comportamento do Sono REM/diagnóstico , Anosmia/complicações , Sintomas Prodrômicos , População do Leste Asiático , Constipação Intestinal/complicações
16.
BMC Public Health ; 23(1): 2520, 2023 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104101

RESUMO

BACKGROUND: The abject uncertainty and unpredictability of public health emergencies have plagued various countries. Global health governance and international communities are facing long-term and arduous challenges. The self-rescue ability of individuals in a public emergency may be the most powerful trait to improve the survival rate outside the hospital. The study explores the cognitive ability and attitudes of urban residents in China towards self-rescue in response to public health emergencies. It provides appropriate evidence for improving the self-rescue ability of urban residents in China. METHODS: Sixteen urban residents were selected using the purposive sampling method for semi-structured interviews. Theme analysis was used to collate and analyse the interview data. RESULTS: Two themes and five sub-themes were analysed. The two themes included cognition and attitude of Chinese urban residents for self-rescue in an emergency. Urban residents believed that their knowledge and skills for self-rescue in an emergency were low. The ability for emergency self-rescue is affected by multiple factors, with relatively limited options for improvement. Nonetheless, the respondents expressed a desire to accept interventions under psychological crisis and a strong willingness to acquire knowledge and skills required for emergency self-rescue. CONCLUSION: This study investigated the perceptions and attitudes of Chinese urban residents towards emergency self-rescue. The results support enhanced ability of urban residents to respond to public health emergencies, thereby diminishing the negative outcomes. The findings suggest the need for strategies to address the factors affecting emergency self-rescue.


Assuntos
Emergências , Saúde Pública , Humanos , População Urbana , Inquéritos e Questionários , China
17.
Proc Natl Acad Sci U S A ; 117(48): 30679-30686, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33184173

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of COVID 19, continues to evolve since its first emergence in December 2019. Using the complete sequences of 1,932 SARS-CoV-2 genomes, various clustering analyses consistently identified six types of the strains. Independent of the dendrogram construction, 13 signature variations in the form of single nucleotide variations (SNVs) in protein coding regions and one SNV in the 5' untranslated region (UTR) were identified and provided a direct interpretation for the six types (types I to VI). The six types of the strains and their underlying signature SNVs were validated in two subsequent analyses of 6,228 and 38,248 SARS-CoV-2 genomes which became available later. To date, type VI, characterized by the four signature SNVs C241T (5'UTR), C3037T (nsp3 F924F), C14408T (nsp12 P4715L), and A23403G (Spike D614G), with strong allelic associations, has become the dominant type. Since C241T is in the 5' UTR with uncertain significance and the characteristics can be captured by the other three strongly associated SNVs, we focus on the other three. The increasing frequency of the type VI haplotype 3037T-14408T-23403G in the majority of the submitted samples in various countries suggests a possible fitness gain conferred by the type VI signature SNVs. The fact that strains missing one or two of these signature SNVs fail to persist implies possible interactions among these SNVs. Later SNVs such as G28881A, G28882A, and G28883C have emerged with strong allelic associations, forming new subtypes. This study suggests that SNVs may become an important consideration in SARS-CoV-2 classification and surveillance.


Assuntos
Alelos , Genoma Viral , Genômica , SARS-CoV-2/genética , Geografia , Humanos , Polimorfismo de Nucleotídeo Único/genética , Fatores de Tempo
18.
Hum Factors ; : 187208231183874, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37387305

RESUMO

OBJECTIVE: This study proposed a moving average (MA) approach to dynamically process heart rate variability (HRV) and developed aberrant driving behavior (ADB) prediction models by using long short-term memory (LSTM) networks. BACKGROUND: Fatigue-associated ADBs have traffic safety implications. Numerous models to predict such acts based on physiological responses have been developed but are still in embryonic stages. METHOD: This study recorded the data of 20 commercial bus drivers during their routine tasks on four consecutive days and subsequently asked them to complete questionnaires, including subjective sleep quality, driver behavior questionnaire and the Karolinska Sleepiness Scale. Driving behaviors and corresponding HRV were determined using a navigational mobile application and a wristwatch. The dynamic-weighted MA (DWMA) and exponential-weighted MA were used to process HRV in 5-min intervals. The data were independently separated for training and testing. Models were trained with 10-fold cross-validation strategy, their accuracies were evaluated, and Shapley additive explanation (SHAP) values were used to determine feature importance. RESULTS: Significant increases in the standard deviation of NN intervals (SDNN), root mean square of successive heartbeat interval differences (RMSSD), and normalized spectrum of high frequency (nHF) were observed in the pre-event stage. The DWMA-based model exhibited the highest accuracy for both driver types (urban: 84.41%; highway: 80.56%). The SDNN, RMSSD, and nHF demonstrated relatively high SHAP values. CONCLUSION: HRV metrics can serve as indicators of mental fatigue. DWMA-based LSTM could predict the occurrence of the level of fatigue associated with ADBs. APPLICATION: The established models can be used in realistic driving scenarios.

19.
Int Wound J ; 20(7): 2511-2517, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36756688

RESUMO

Recurrence of pressure ulcers following reconstructive surgery occurs frequently, causing a significant burden on the patient and the public health care system. We assessed risk factors for the recurrence of pressure ulcers based on the experience of a single surgeon at our medical centre. We retrospectively analysed patients admitted to our medical centre with stage III and IV pressure ulcers who underwent reconstructive surgery. The hospital database was searched for patients diagnosed with pressure ulcers who underwent reconstructive surgery. Patient characteristics analysed included age, sex, cause and location of defect, comorbidities, lesion size, wound reconstruction methods, operation time, debridement times, duration of hospital stay, and wound complications. Recurrence and mortality rates were retrospectively examined. One hundred and eighty-nine patients were enrolled, and 166 patients with 176 pressure ulcers met our inclusion criteria. All 14 recurrences (7.95%) were followed for at least 1 year. Logistic regression analysis indicated that recurrence was associated with albumin levels (P = 0.001) and wound size (P = 0.043); however, no association was found for body mass index, bacterial profile, comorbidities, localisation, previous surgery, operation time, or time to admission for reconstruction. In conclusion, higher albumin levels were associated with lower recurrence rates in patients who underwent reconstructive surgery.


Assuntos
Procedimentos de Cirurgia Plástica , Úlcera por Pressão , Cirurgia Plástica , Humanos , Procedimentos de Cirurgia Plástica/efeitos adversos , Estudos Retrospectivos , Cicatrização , Úlcera por Pressão/etiologia , Úlcera por Pressão/cirurgia , Úlcera por Pressão/diagnóstico , Hospitais , Fatores de Risco , Albuminas
20.
J Virol ; 95(12)2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-33827946

RESUMO

Broadly neutralizing antibodies (bNAbs) are the focus of increasing interest for human immunodeficiency virus type 1 (HIV-1) prevention and treatment. Although several bNAbs are already under clinical evaluation, the development of antibodies with even greater potency and breadth remains a priority. Recently, we reported a novel strategy for improving bNAbs against the CD4-binding site (CD4bs) of gp120 by engraftment of the elongated framework region 3 (FR3) from VRC03, which confers the ability to establish quaternary interactions with a second gp120 protomer. Here, we applied this strategy to a new series of anti-CD4bs bNAbs (N49 lineage) that already possess high potency and breadth. The resultant chimeric antibodies bound the HIV-1 envelope (Env) trimer with a higher affinity than their parental forms. Likewise, their neutralizing capacity against a global panel of HIV-1 Envs was also increased. The introduction of additional modifications further enhanced the neutralization potency. We also tried engrafting the elongated CDR1 of the heavy chain from bNAb 1-18, another highly potent quaternary-binding antibody, onto several VRC01-class bNAbs, but none of them was improved. These findings point to the highly selective requirements for the establishment of quaternary contact with the HIV-1 Env trimer. The improved anti-CD4bs antibodies reported here may provide a helpful complement to current antibody-based protocols for the therapy and prevention of HIV-1 infection.IMPORTANCE Monoclonal antibodies represent one of the most important recent innovations in the fight against infectious diseases. Although potent antibodies can be cloned from infected individuals, various strategies can be employed to improve their activity or pharmacological features. Here, we improved a lineage of very potent antibodies that target the receptor-binding site of HIV-1 by engineering chimeric molecules containing a fragment from a different monoclonal antibody. These engineered antibodies are promising candidates for development of therapeutic or preventive approaches against HIV/AIDS.


Assuntos
Sítios de Ligação de Anticorpos , Anticorpos Amplamente Neutralizantes/imunologia , Antígenos CD4/metabolismo , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Engenharia de Proteínas , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Sítios de Ligação , Sítios de Ligação de Anticorpos/imunologia , Anticorpos Amplamente Neutralizantes/química , Anticorpos Amplamente Neutralizantes/genética , Anticorpos Amplamente Neutralizantes/uso terapêutico , Antígenos CD4/química , Epitopos/química , Epitopos/imunologia , Anticorpos Anti-HIV/química , Anticorpos Anti-HIV/genética , Anticorpos Anti-HIV/uso terapêutico , Proteína gp120 do Envelope de HIV/metabolismo , Infecções por HIV/prevenção & controle , Infecções por HIV/terapia , Humanos , Modelos Moleculares , Mutação , Ligação Proteica , Multimerização Proteica , Subunidades Proteicas/química
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