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1.
Risk Manag Healthc Policy ; 16: 2263-2279, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38024495

RESUMO

Background: Medical disputes are a recurrent and pressing issue in hospitals, posing significant challenges to the functioning of medical institutions. We aimed to investigate whether receiving rule of law publicity on short video platforms is relevant to preventing medical disputes among healthcare professionals. Methods: We collected the data from 37,978 medical professionals from 130 tertiary public hospitals. Participants were classified into two groups according to the presence of receiving rule of law publicity on short video platforms. A subgroup analysis was performed before and after propensity score analysis, and multiple logistic regression was used to identify risk factors for medical disputes. Results: Among all participants, 46.1% (17,506/37,978) experienced medical disputes. Before propensity score analysis, the prevalence of medical disputes among participants who received rule of law publicity on short video platforms was similar to that among participants who did not (P = 0.639). However, after propensity score analysis, participants who received the rule of law publicity on short video platforms did not show a benefit effect. These participants had a significantly higher rate of suffering from medical disputes than participants who did not receive publicity on this platform (P=0.020). Multiple logistic regression analysis confirmed that receiving the rule of law publicity through short video platforms (P=0.010) or MicroBlog (P = 0.016), and previously facing legal issues outside of medical work (P < 0.001) were risk factors for medical disputes; participating in legal training organized by hospitals (P=0.004) and the hospital rule of law being very good (P=0.045) were protective factors. Conclusion: Medical disputes are a common occurrence within the healthcare profession. However, using short video platforms to promote the rule of law is not an effective method to prevent disputes. Instead, healthcare professionals can benefit from participating in legal training and having a well-established rule of law within the hospital construct.

2.
J Med Internet Res ; 25: e46854, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37590041

RESUMO

BACKGROUND: Medical disputes are a global public health issue that is receiving increasing attention. However, studies investigating the relationship between hospital legal construction and medical disputes are scarce. The development of a multicenter model incorporating machine learning (ML) techniques for the individualized prediction of medical disputes would be beneficial for medical workers. OBJECTIVE: This study aimed to identify predictors related to medical disputes from the perspective of hospital legal construction and the use of ML techniques to build models for predicting the risk of medical disputes. METHODS: This study enrolled 38,053 medical workers from 130 tertiary hospitals in Hunan province, China. The participants were randomly divided into a training cohort (34,286/38,053, 90.1%) and an internal validation cohort (3767/38,053, 9.9%). Medical workers from 87 tertiary hospitals in Beijing were included in an external validation cohort (26,285/26,285, 100%). This study used logistic regression and 5 ML techniques: decision tree, random forest, support vector machine, gradient boosting decision tree (GBDT), and deep neural network. In total, 12 metrics, including discrimination and calibration, were used for performance evaluation. A scoring system was developed to select the optimal model. Shapley additive explanations was used to generate the importance coefficients for characteristics. To promote the clinical practice of our proposed optimal model, reclassification of patients was performed, and a web-based app for medical dispute prediction was created, which can be easily accessed by the public. RESULTS: Medical disputes occurred among 46.06% (17,527/38,053) of the medical workers in Hunan province, China. Among the 26 clinical characteristics, multivariate analysis demonstrated that 18 characteristics were significantly associated with medical disputes, and these characteristics were used for ML model development. Among the ML techniques, GBDT was identified as the optimal model, demonstrating the lowest Brier score (0.205), highest area under the receiver operating characteristic curve (0.738, 95% CI 0.722-0.754), and the largest discrimination slope (0.172) and Youden index (1.355). In addition, it achieved the highest metrics score (63 points), followed by deep neural network (46 points) and random forest (45 points), in the internal validation set. In the external validation set, GBDT still performed comparably, achieving the second highest metrics score (52 points). The high-risk group had more than twice the odds of experiencing medical disputes compared with the low-risk group. CONCLUSIONS: We established a prediction model to stratify medical workers into different risk groups for encountering medical disputes. Among the 5 ML models, GBDT demonstrated the optimal comprehensive performance and was used to construct the web-based app. Our proposed model can serve as a useful tool for identifying medical workers at high risk of medical disputes. We believe that preventive strategies should be implemented for the high-risk group.


Assuntos
Dissidências e Disputas , Pessoal de Saúde , Humanos , Estudos Transversais , Aprendizado de Máquina , Centros de Atenção Terciária
4.
Stem Cells Dev ; 32(17-18): 554-564, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37261981

RESUMO

Dax1 (Nr0b1; Dosage-sensitive sex reversal-adrenal hypoplasia congenital on the X-chromosome gene-1) is an important component of the transcription factor network that governs pluripotency in mouse embryonic stem cells (ESCs). Functional evaluation of alternative splice variants of pluripotent transcription factors has shed additional insight on the maintenance of ESC pluripotency and self-renewal. Dax1 splice variants have not been identified and characterized in mouse ESCs. We identified 18 new transcripts of Dax1 with putative protein-coding properties and compared their protein structures with known Dax1 protein (Dax1-472). The expression pattern analysis showed that the novel isoforms were cotranscribed with Dax1-472 in mouse ESCs, but they had transcriptional heterogeneity among single cells and the subcellular localization of the encoded proteins differed. Cell function experiments indicated that Dax1-404 repressed Gata6 transcription and functionally replaced Dax1-472, while Dax1-38 and Dax1-225 partially antagonized Dax1-472 transcriptional repression. This study provided a comprehensive characterization of the Dax1 splice variants in mouse ESCs and suggested complex effects of Dax1 variants in a self-renewal regulatory network.


Assuntos
Receptor Nuclear Órfão DAX-1 , Células-Tronco Embrionárias , Células-Tronco Embrionárias Murinas , Animais , Camundongos , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Expressão Gênica , Regulação da Expressão Gênica , Células-Tronco Embrionárias Murinas/metabolismo , Fatores de Transcrição/metabolismo , Receptor Nuclear Órfão DAX-1/genética , Receptor Nuclear Órfão DAX-1/metabolismo
5.
Stem Cells Dev ; 32(15-16): 450-464, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37166379

RESUMO

The pluripotency of embryonic stem cells (ESCs) is more accurately viewed as a continuous developmental process rather than a fixed state. However, the factors that play general or state-specific roles in regulating self-renewal in different pluripotency states remain poorly defined. In this study, parallel genome-wide CRISPR/Cas9 knockout (KO) screens were applied in ESCs cultured in the serum plus LIF (SL) and in the 2i plus LIF (2iL) conditions. The candidate genes were classified into seven groups based on their positive or negative effects on self-renewal, and whether this effect was general or state-specific for ESCs under SL and 2iL culture conditions. We characterized the expression and function of genes in these seven groups. The loss of function of novel pluripotent candidate genes Usp28, Zfp598, and Zfp296 was further evaluated in mouse ESCs. Consistent with our screen, the knockout of Usp28 promotes the proliferation of SL-ESCs and 2iL-ESCs, whereas Zfp598 is indispensable for the self-renewal of ESCs under both culture conditions. The cell phenotypes of Zfp296 KO ESCs under SL and 2iL culture conditions were different. Our work provided a valuable resource for dissecting the molecular regulation of ESC self-renewal in different pluripotency states.


Assuntos
Células-Tronco Embrionárias , Células-Tronco Embrionárias Murinas , Camundongos , Animais , Diferenciação Celular/genética
6.
Commun Biol ; 6(1): 410, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37059858

RESUMO

A comprehensive and precise definition of the pluripotency gene regulatory network (PGRN) is crucial for clarifying the regulatory mechanisms in embryonic stem cells (ESCs). Here, after a CRISPR/Cas9-based functional genomics screen and integrative analysis with other functional genomes, transcriptomes, proteomes and epigenome data, an expanded pluripotency-associated gene set is obtained, and a new PGRN with nine sub-classes is constructed. By integrating the DNA binding, epigenetic modification, chromatin conformation, and RNA expression profiles, the PGRN is resolved to six functionally independent transcriptional modules (CORE, MYC, PAF, PRC, PCGF and TBX). Spatiotemporal transcriptomics reveal activated CORE/MYC/PAF module activity and repressed PRC/PCGF/TBX module activity in both mouse ESCs (mESCs) and pluripotent cells of early embryos. Moreover, this module activity pattern is found to be shared by human ESCs (hESCs) and cancers. Thus, our results provide novel insights into elucidating the molecular basis of ESC pluripotency.


Assuntos
Células-Tronco Pluripotentes , Animais , Camundongos , Humanos , Células-Tronco Pluripotentes/metabolismo , Multiômica , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Cromatina/genética , Cromatina/metabolismo
7.
FEBS Open Bio ; 13(6): 1001-1014, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37098971

RESUMO

As a key effector of the Hippo pathway, yes-associated protein (YAP) is a major regulator of cell proliferation and apoptosis. In this study, 23 hYAP isoforms were identified in HEK293 cells, with 14 isoforms being reported for the first time. These isoforms were classified into hYAP-a and hYAP-b isoforms based on the variation in exon 1. The two groups of isoforms showed distinctly different subcellular localizations. hYAP-a isoforms could activate TEAD- or P73-mediated transcription, affect the proliferation rate, and enhance the cellular chemosensitivity of HEK293 cells. Moreover, different activation abilities and pro-cytotoxic effects were observed among hYAP-a isoforms. However, hYAP-b isoforms were not found to exert any significant biological effects. Our findings add to the knowledge of YAP gene structure and protein-coding capacity and will help in the elucidation of the function and related molecular mechanisms of the Hippo-YAP signaling pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Via de Sinalização Hippo , Fatores de Transcrição , Humanos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células HEK293 , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Gene Expr Patterns ; 47: 119302, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36516960

RESUMO

Transcriptional enhanced associate domain (TEAD) transcription factors play important roles in embryonic stem cell (ESC) renewal and differentiation. Four TEAD transcription factors (Tead1, Tead2, Tead3 and Tead4) and their various splice variants have been discovered in mice, but the expression pattern of them during pluripotency state transition is unclear. Here, we investigated the expression of TEADs and their splice variants in mouse ESCs at different pluripotent/differentiating states and adult mouse tissues. Our results preliminarily revealed the diversity and heterogeneity of TEAD family, which is helpful for understanding their overlapping and distinctive functions. Furthermore, a novel splice variant of Tead1 was identified and named Tead1 isoform 4.


Assuntos
Diferenciação Celular , Autorrenovação Celular , Células-Tronco Embrionárias Murinas , Fatores de Transcrição de Domínio TEA , Diferenciação Celular/genética , Proliferação de Células/genética , Autorrenovação Celular/genética , Perfilação da Expressão Gênica , Células-Tronco Embrionárias Murinas/metabolismo , Isoformas de RNA/genética , Splicing de RNA/genética , Fatores de Transcrição de Domínio TEA/genética , Fatores de Transcrição de Domínio TEA/metabolismo , Processamento Alternativo/genética , Células Cultivadas
9.
Front Public Health ; 10: 993946, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159280

RESUMO

Background: Medical disputes are common in hospitals and a major challenge for the operations of medical institutions. However, few studies have looked into the association between medical disputes and hospital legal constructions. The purpose of the study was to investigate the relationship between hospital legal constructions and medical disputes, and it also aimed to develop a nomogram to estimate the likelihood of medical disputes. Methods: Between July and September 2021, 2,716 administrators from 130 hospitals were enrolled for analysis. The study collected seventeen variables for examination. To establish a nomogram, administrators were randomly split into a training group (n = 1,358) and a validation group (n = 1,358) with a 50:50 ratio. The nomogram was developed using data from participants in the training group, and it was validated in the validation group. The nomogram contained significant variables that were linked to medical disputes and were identified by multivariate analysis. The nomogram's predictive performance was assessed utilizing discriminative and calibrating ability. A web calculator was developed to be conducive to model utility. Results: Medical disputes were observed in 41.53% (1,128/2,716) of participants. Five characteristics, including male gender, higher professional ranks, longer length of service, worse understanding of the hospital charters, and worse construction status of hospital rule of law, were significantly associated with more medical disputes based on the multivariate analysis. As a result, these variables were included in the nomogram development. The AUROC was 0.67 [95% confident interval (CI): 0.64-0.70] in the training group and 0.68 (95% CI: 0.66-0.71) in the validation group. The corresponding calibration slopes were 1.00 and 1.05, respectively, and intercepts were 0.00 and -0.06, respectively. Three risk groups were created among the participants: Those in the high-risk group experienced medical disputes 2.83 times more frequently than those in the low-risk group (P < 0.001). Conclusion: Medical dispute is prevailing among hospital administrators, and it can be reduced by the effective constructions of hospital rule of law. This study proposes a novel nomogram to estimate the likelihood of medical disputes specifically among administrators in tertiary hospitals, and a web calculator can be available at https://ymgarden.shinyapps.io/Predictionofmedicaldisputes/.


Assuntos
Dissidências e Disputas , Nomogramas , China , Humanos , Masculino , Fatores de Risco , Centros de Atenção Terciária
10.
Front Public Health ; 10: 765624, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309213

RESUMO

The carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) poses a severe therapeutic challenge to global public health, and research on CR-hvKP in older patients remain limited. In this study, we aimed to investigate the clinical and molecular characteristics and risk factors of CR-hvKP infections in older patients. We retrospectively investigated older patients with carbapenem-resistant Klebsiella pneumoniae (CRKP) infections in the intensive care unit (ICU) between January 2020 and December 2020. The clinical data, and microbiological data including antimicrobial susceptibility testing, phenotype experiment and detection of carbapenemases, string test, virulence genes, capsular serotype-specific (cps) genes, and multilocus sequence typing, of the CR-hvKP group defined by the presence of any one of the virulence genes, including rmpA, rmpA2, iucA, iroN, and peg-344 were compared with those of CR-non-hvKP strains. Of the 80 CRKP strains, 51 (63.8%) met the definition of CR-hvKP. The main mechanism of resistance to carbapenems was the presence of the blaKPC-2 gene. Sequence type (ST)11 (81.3%, 65/80) and ST15 (16.3%, 13/80) were the most common STs in CRKP strains. The minimum inhibitory concentration (MIC)50 values of the CR-hvKP group against the six tested antibiotics (ceftazidime, ceftazidime-avibactam, imipenem-avibactam, tigecycline, levofloxacin, and Cefoperazone-Sulbactam) exhibited elevated levels than the CR-non-hvKP group. Ceftazidime and imipenem by combining avibactam (4 µg/mL) significantly decreased the MIC90 values more than 16-fold than ceftazidime and imipenem alone against Klebsiella pneumoniae carbapenemase (KPC)-2-producing K. pneumoniae. Cardiovascular disease [odds ratio (OR) = 11.956] and ST11-K64 (OR = 8.385) appeared to be independent variables associated with CR-hvKP infection by multivariate analysis. In conclusion, higher MICs of the last line antibiotic agents (ceftazidime-avibactam, tigecycline) might be a critical consideration in the clinical management of older patients where the concentration of these toxic antibiotics matters because of underlying comorbidities. Caution regarding KPC-2-producing ST11-K64 CR-hvKP as being new significant "superbugs" is required as they are widespread, and infection control measures should be strengthened to curb further dissemination in nosocomial settings in China.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Carbapenêmicos/farmacologia , Ceftazidima , Humanos , Imipenem , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Estudos Retrospectivos , Tigeciclina
11.
Herz ; 47(6): 553-563, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35089369

RESUMO

BACKGROUND: Previous studies have investigated the close association between the MTHFR C677T polymorphism and the risk of coronary heart disease (CAD) in the Chinese population. However, the results remain inconclusive. Therefore, this meta-analysis was performed to derive a more precise estimate of these associations. METHODS: Odds ratios (OR) with 95% confidence intervals (CI) were used to assess the relationship between the MTHFR C677T polymorphism and the risk of CAD. Studies were identified by searching the literature for articles published before 2017. RESULTS: A total of 39 studies comprising 12,101 individuals (6117 cases and 5984 controls) were included. For the allelic model T vs. C, the pooled OR was 1.43 (95% CI: 1.30-1.57, p < 0.0001); for the recessive model TT vs. CC + TC, the pooled OR was 1.48 (95% CI: 1.29-1.70, p < 0.0001); for the dominant model TT + TC vs. CC, the pooled OR was 1.65 (95% CI: 1.43-1.89, p < 0.0001). CONCLUSION: In the subgroup analysis of high-quality studies, an obvious association was observed between the MTHFR C677T polymorphism and CAD risk in the Chinese population.


Assuntos
Doença da Artéria Coronariana , Metilenotetra-Hidrofolato Redutase (NADPH2) , Humanos , Povo Asiático/genética , China/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/genética , Predisposição Genética para Doença/epidemiologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco
12.
Stem Cells Dev ; 31(5-6): 132-142, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35019759

RESUMO

The mechanisms underlying self-renewal of embryonic stem cells (ESCs) hold great value in the clinical translation of stem cell biology and regenerative medicine research. To study the mechanisms in ESC self-renewal, screening and identification of key genes maintaining ESC self-renewal were performed by a genome-wide CRISPR-Cas9 knockout virus library. The mouse ESC R1 were infected with CRISPR-Cas9 knockout virus library and cultured for 14 days. The variation of single guide RNA (sgRNA) ratio was analyzed by high-throughput sequencing, followed by bioinformatics analysis to profile the altered genes. Our results showed 1375 genes with increased sgRNA ratio were found to be mainly involved in signal transduction, cell differentiation, and cell apoptosis; 2929 genes with decreased sgRNA ratio were mainly involved in cell cycle regulation, RNA splicing, and biological metabolic processes. We further confirmed our screen specificity by identifying Puf60, U2af2, Wdr75, and Usp16 as novel positive regulators in mESC self-renewal. Meanwhile, further analysis showed the relevance between Puf60 expression and tumor. In conclusion, our study screened key genes maintaining ESC self-renewal and successfully identified Puf60, U2af2, Wdr75, and Usp16 as novel positive regulators in mESC self-renewal, which provided theoretical basis and research clues for a better understanding of ESC self-renewal regulation.


Assuntos
Células-Tronco Embrionárias , Células-Tronco Embrionárias Murinas , Animais , Diferenciação Celular/genética , Camundongos , Transdução de Sinais
14.
IUBMB Life ; 73(12): 1432-1445, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34687583

RESUMO

Hippo signaling pathway is involved in many biological processes including the fate decision of embryonic stem cells (ESCs). Yes-associated protein (Yap) function as a key effector of Hippo pathway, but its role in ESCs is still controversial. So far, only two isoforms of Yap have been identified and they have both overlapping and distinct functions. Here, we identify six novel isoforms of mouse Yap, bringing the total number of isoforms to eight. According to the differences in the first exon, they are divided into two subtypes (a and b). Isoform-a and isoform-b exhibit different subcellular localizations. Moreover, isoform-a can fully reverse the impaired self-renewal phenotype induced by Yap knockout (KO). Upon overexpression, isoform-a moderately promotes mESCs self-renewal and markedly delays differentiation. On the contrary, no significant pro-self-renewal phenotype is observed when isoform-b overexpressed in wildtype (WT) mESCs or re-expressed in Yap KO cell lines. These finding not only help to clarify the role of Yap in mESCs, but also lay the foundation for advancing functional researches of Yap in other processes.


Assuntos
Fenômenos Biológicos , Células-Tronco Embrionárias Murinas , Proteínas de Sinalização YAP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Células-Tronco Embrionárias/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
15.
Stem Cells Int ; 2021: 5522723, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335791

RESUMO

Dax1(also known as Nr0b1) is regarded as an important component of the transcription factor network in mouse embryonic stem cells (ESCs). However, the role and the molecular mechanism of Dax1 in the maintenance of different pluripotency states are poorly understood. Here, we constructed a stable Dax1 knockout (KO) cell line using the CRISPR/Cas9 system to analyze the precise function of Dax1. We reported that 2i/LIF-ESCs had significantly lower Dax1 expression than LIF/serum-ESCs. Dax1KO ES cell lines could be established in 2i/LIF and their pluripotency was confirmed. In contrast, Dax1-null ESCs could not be continuously passaged in LIF/serum due to severe differentiation and apoptosis. In LIF/serum, the activities of the Core module and Myc module were significantly reduced, while the PRC2 module was activated after Dax1KO. The expression of most proapoptotic genes and lineage-commitment genes were drastically increased, while the downregulated expression of antiapoptotic genes and many pluripotency genes was observed. Our research on the pluripotent state-dependent role of Dax1 provides clues to understand the molecular regulation mechanism at different stages of early embryonic development.

16.
Stem Cells ; 39(9): 1178-1191, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33938099

RESUMO

Yap is the key effector of Hippo signaling; however, its role in embryonic stem cells (ESCs) remains controversial. Here, we identify two Yap splicing isoforms (Yap472 and Yap488), which show equal expression levels but heterogeneous distribution in ESCs. Knockout (KO) of both isoforms reduces ESC self-renewal, accelerates pluripotency exit, but arrests terminal differentiation, while overexpression of each isoform leads to the reverse phenotype. The effect of both Yap isoforms on self-renewal is Teads-dependent and mediated by c-Myc. Nonetheless, different isoforms are found to affect overlapping yet distinct genes, and confer different developmental potential to Yap-KO cells, with Yap472 exerting a more pronounced biological effect and being more essential for neuroectoderm differentiation. Constitutive activation of Yaps, particularly Yap472, dramatically upregulates p53 and Cdx2, inducing trophectoderm trans-differentiation even under self-renewal conditions. These findings reveal the combined roles of different Yap splicing isoforms and mechanisms in regulating self-renewal efficiency and differentiation potential of ESCs.


Assuntos
Desenvolvimento Embrionário , Células-Tronco Embrionárias , Diferenciação Celular/genética , Células-Tronco Embrionárias/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
17.
Cell Mol Immunol ; 18(3): 675-685, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32235917

RESUMO

Induction of broadly neutralizing monoclonal antibodies (bNAbs) that bind to the viral envelope glycoproteins is a major goal of hepatitis C virus (HCV) vaccine research. The study of bNAbs arising in natural infection is essential in this endeavor. We generated a human antibody, 8D6, recognizing the E2 protein of HCV isolated from a chronic hepatitis C patient. This antibody shows broadly neutralizing activity, which covers a pan-genotypic panel of cell culture-derived HCV virions (HCVcc). Functional and epitope analyses demonstrated that 8D6 can block the interaction between E2 and CD81 by targeting a highly conserved epitope on E2. We describe how the 8D6 lineage evolved via somatic hypermutation to achieve broad neutralization. We found that the V(D)J recombination-generated junctional and somatic hypermutation-induced disulfide bridge (C-C) motif in the CDRH3 is critical for the broad neutralization and binding activity of 8D6. This motif is conserved among a series of broadly neutralizing HCV antibodies, indicating a common binding model. Next, the 8D6 inferred germline (iGL) was reconstructed and tested for its binding affinity and neutralization activity. Interestingly, 8D6 iGL-mediated relatively strong inhibition of the 1b genotype PR79L9 strain, suggesting that PR79L9 may serve as a potential natural viral strain that provides E2 sequences that induce bNAbs. Overall, our detailed epitope mapping and genetic studies of the HCV E2-specific mAb 8D6 have allowed for further refinement of antigenic sites on E2 and reveal a new mechanism to generate a functional CDRH3, while its iGL can serve as a probe to identify potential HCV vaccine strains.


Assuntos
Anticorpos Amplamente Neutralizantes/farmacologia , Regiões Determinantes de Complementaridade/genética , Epitopos/imunologia , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/imunologia , Hepatite C/prevenção & controle , Proteínas do Envelope Viral/imunologia , Anticorpos Monoclonais/farmacologia , Regiões Determinantes de Complementaridade/imunologia , Mapeamento de Epitopos , Hepatite C/genética , Hepatite C/imunologia , Hepatite C/virologia , Humanos , Cadeias Pesadas de Imunoglobulinas , Mutação , Domínios e Motivos de Interação entre Proteínas
18.
Gene ; 773: 145383, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33383118

RESUMO

Alternative splicing (AS) is a key process to expand the diversity of mRNA and protein from the genome and it is crucial for fate determination of embryonic stem cells (ESCs) by encoding isoforms with different functions to regulate the balance between pluripotency maintenance and differentiation. Since the role of the Hippo pathway in ESCs is controversial, there may be novel isoforms of Taz, a key effector of the Hippo pathway, previously unknown to us. Here, we identified three variants of Taz in mESCs. Apart from the canonical Taz1185, there were also two novel variants, Taz402 and Taz1086. We found their structure and subcellular localization to be different, while they could all interact with TEAD2 with similar binding affinities and activate transcription. Under the LIFlow condition, overexpression of them all induced apoptosis and differentiation of mESCs, among which the phenotype of Taz1086 was the most dramatic. Taken together, we discovered novel variants of Taz and compared their structure and functional differences in mESC pluripotency maintenance. These findings will help us to understand the Taz gene and clarify its role in mESC.


Assuntos
Processamento Alternativo/genética , Proteínas de Ligação a DNA/genética , Células-Tronco Embrionárias Murinas/metabolismo , Transativadores/genética , Fatores de Transcrição/genética , Proteínas Adaptadoras de Transdução de Sinal , Animais , Apoptose/genética , Diferenciação Celular/genética , Regulação da Expressão Gênica/genética , Camundongos , Células-Tronco Pluripotentes/metabolismo , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Fatores de Transcrição de Domínio TEA
19.
Biochem Biophys Res Commun ; 532(3): 377-384, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32883521

RESUMO

Embryonic stem (ES) cells are unique in their ability to self-renew indefinitely while maintaining pluripotency. Krüppel-like factor (Klf) 4 is an important member of the Klf family that is known to play a key role in pluripotency and somatic cell reprogramming. However, the identification and functional comparison of Klf4 splicing isoforms in mouse ESCs (mESCs) remains to be elucidated. Here, we identified three novel alternative splicing variants of Klf4 in mESCs-mKlf4-108, mKlf4-375 and mKlf4-1482-that are distinct from the previously known mKlf4-1449. mKlf4-1449 and mKlf4-1482 may stimulate the growth of ESCs, while mKlf4-108 can only promote the growth of ESCs in LIFlow/serum conditions. In addition, both mKlf4-1449 and mKlf4-1482 can inhibit the differentiation of mESCs. However, the ability of mKlf4-1482 to promote self-renewal and inhibit differentiation is not as strong as that of mKlf4-1449. In contrast, both mKlf4-108 and mKlf4-375 may have the ability to induce endodermal differentiation. Taken together, we have identified for the first time the existence of alternative splicing variants of mKlf4 and have revealed their different roles, which provide new insights into the contribution of Klf4 to the self-renewal and pluripotency of mouse ESCs.


Assuntos
Processamento Alternativo , Autorrenovação Celular/genética , Autorrenovação Celular/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/fisiologia , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/fisiologia , Animais , Sequência de Bases , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular , Códon sem Sentido , Fator 4 Semelhante a Kruppel , Camundongos , Modelos Biológicos , Poli A/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/fisiologia
20.
Appl Opt ; 56(8): 2255-2259, 2017 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-28375315

RESUMO

Optical coherence tomography (OCT) allows noncontact acquisition of fingerprints and hence is a highly promising technology in the field of biometrics. OCT can be used to acquire both structural and microangiographic images of fingerprints. Microangiographic OCT derives its contrast from the blood flow in the vasculature of viable skin tissue, and microangiographic fingerprint imaging is inherently immune to fake fingerprint attack. Therefore, dual-modality (structural and microangiographic) OCT imaging of fingerprints will enable more secure acquisition of biometric data, which has not been investigated before. Our study on fingerprint identification based on structural and microangiographic OCT imaging is, we believe, highly innovative. In this study, we performed OCT imaging study for fingerprint acquisition, and demonstrated the capability of dual-modality OCT imaging for the identification of fake fingerprints.


Assuntos
Angiografia/métodos , Dermatoglifia , Tomografia de Coerência Óptica/métodos , Dedos/irrigação sanguínea , Humanos
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