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1.
Circulation ; 149(17): 1375-1390, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38214189

RESUMO

BACKGROUND: Cardiac transverse tubules (T-tubules) are anchored to sarcomeric Z-discs by costameres to establish a regular spaced pattern. One of the major components of costameres is the dystrophin-glycoprotein complex (DGC). Nevertheless, how the assembly of the DGC coordinates with the formation and maintenance of T-tubules under physiological and pathological conditions remains unclear. METHODS: Given the known role of Ptpn23 (protein tyrosine phosphatase, nonreceptor type 23) in regulating membrane deformation, its expression in patients with dilated cardiomyopathy was determined. Taking advantage of Cre/Loxp, CRISPR/Cas9, and adeno-associated virus 9 (AAV9)-mediated in vivo gene editing, we generated cardiomyocyte-specific Ptpn23 and Actn2 (α-actinin-2, a major component of Z-discs) knockout mice. We also perturbed the DGC by using dystrophin global knockout mice (DmdE4*). MM 4-64 and Di-8-ANEPPS staining, Cav3 immunofluorescence, and transmission electron microscopy were performed to determine T-tubule structure in isolated cells and intact hearts. In addition, the assembly of the DGC with Ptpn23 and dystrophin loss of function was determined by glycerol-gradient fractionation and SDS-PAGE analysis. RESULTS: The expression level of Ptpn23 was reduced in failing hearts from dilated cardiomyopathy patients and mice. Genetic deletion of Ptpn23 resulted in disorganized T-tubules with enlarged diameters and progressive dilated cardiomyopathy without affecting sarcomere organization. AAV9-mediated mosaic somatic mutagenesis further indicated a cell-autonomous role of Ptpn23 in regulating T-tubule formation. Genetic and biochemical analyses showed that Ptpn23 was essential for the integrity of costameres, which anchor the T-tubule membrane to Z-discs, through interactions with α-actinin and dystrophin. Deletion of α-actinin altered the subcellular localization of Ptpn23 and DGCs. In addition, genetic inactivation of dystrophin caused similar T-tubule defects to Ptpn23 loss-of-function without affecting Ptpn23 localization at Z-discs. Last, inducible Ptpn23 knockout at 1 month of age showed Ptpn23 is also required for the maintenance of T-tubules in adult cardiomyocytes. CONCLUSIONS: Ptpn23 is essential for cardiac T-tubule formation and maintenance along Z-discs. During postnatal heart development, Ptpn23 interacts with sarcomeric α-actinin and coordinates the assembly of the DGC at costameres to sculpt T-tubule spatial patterning and morphology.

2.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445978

RESUMO

Autophagy has stabilizing functions for cardiomyocytes. Recent studies indicate that an impairment in the autophagy pathway can seriously affect morphology and function, potentially leading to heart failure. However, the role and the underlying mechanism of the endosomal sorting complex required for transport (ESCRT) family protein, in particular the AAA-ATPase vacuolar protein sorting 4a (Vps4a), in regulating myocardial autophagy remains unclear. In the present study, cardiomyocyte-specific Vps4a knockout mice were generated by crossing Vps4aflox/flox (Vps4afl/fl) with Myh6-cre transgenic mice. As a result, we observed a partially dilated left ventricular (LV) chamber, a significant increase in heart weight to body weight ratio (HW/BW), and heart weight to tibial length ratio (HW/TL), hypertrophic cardiomyopathy and early lethality starting at 3 months of age. Hematoxylin-eosin (HE), immunofluorescence assay (IFA), and Western blot (WB) revealed autophagosome accumulation in cardiomyocytes. A transcriptome-based analysis and autophagic flux tracking by AAV-RFP-GFP-LC3 showed that the autophagic flux was blocked in Vps4a knockout cardiomyocytes. In addition, we provided in vitro evidence demonstrating that Vps4a and LC3 were partially co-localized in cardiomyocytes, and the knockdown of Vps4a led to the accumulation of autophagosomes in cardiomyocytes. Similarly, the transfection of cardiomyocytes with adenovirus (Adv) mCherry-GFP-LC3 further indicated that the autophagic flux was blocked in cells with deficient levels of Vps4a. Finally, an electron microscope (EM) showed that the compromised sealing of autophagosome blocked the autophagic flux in Vps4a-depleted cardiomyocytes. These findings revealed that Vps4a contributed to the sealing of autophagosomes in cardiomyocytes. Therefore, we demonstrated that Vps4a deletion could block the autophagic flux, leading to the accumulation of degradation substances and compromised cardiac function. Overall, this study provides insights into a new theoretical basis for which autophagy may represent a therapeutic target for cardiovascular diseases.


Assuntos
Autofagia , Cardiomiopatia Hipertrófica , Camundongos , Animais , Autofagia/genética , Miocárdio/metabolismo , Autofagossomos/metabolismo , Miócitos Cardíacos/metabolismo , Camundongos Transgênicos , Cardiomiopatia Hipertrófica/metabolismo , Camundongos Knockout , Transporte Proteico
3.
Arch Virol ; 163(12): 3225-3234, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30128611

RESUMO

Tembusu virus (TMUV) is an important pathogen that causes acute egg drop syndrome in poultry. To investigate the epidemiological status of Tembusu virus in Zhejiang province, we collected clinical samples and sera from the local area from 2010 to 2016. A total of 41 out of the 88 collected tissue samples were identified as TMUV-infected by RT-PCR and were confirmed by sequencing. Six TMUV strains were isolated from TMUV-positive samples, and their complete genome sequences were determined. In addition, 19 E gene sequences amplified from RT-PCR-positive samples were determined. Sequence identity values among the 19 E genes and reference E sequences ranged from 96.8% to 100.0%, and they ranged from 97.3% to 99.9% when comparing the six genome sequences and references. Nineteen sites with amino acid mutations were identified in the E protein of nineteen strains, and these were at positions that are usually conserved in other TMUV strains. Antibodies to TMUV in serum samples were detected by indirect ELISA using recombinant EDIII (domain III of the E protein) as the antigen. The results showed that TMUV-specific antibodies were widely present in duck populations, with positive rates of 17.38%, 21.99%, 26.68%, and 17.79% in 2013, 2014, 2015 and 2016, respectively. The data from this study provide a good understanding of the epidemiology of TMUV infections in Zhejiang, China.


Assuntos
Infecções por Flavivirus/veterinária , Flavivirus/genética , Flavivirus/isolamento & purificação , Doenças das Aves Domésticas/virologia , Animais , Galinhas , China/epidemiologia , Patos/virologia , Ensaio de Imunoadsorção Enzimática , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/virologia , Genoma Viral , Filogenia , Doenças das Aves Domésticas/epidemiologia , Proteínas Virais/genética
4.
Appl Microbiol Biotechnol ; 102(13): 5645-5656, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29736821

RESUMO

M2 protein, a highly conserved protein of influenza A virus (IAV), plays an important role in virus particle uncoating, assembly, and budding. In the present study, eight monoclonal antibodies (mAbs) against the M2 protein of the H3N2 IAV strain were generated with recombinant truncated M2 protein or BSA-coupled M2 peptides as immunogens. The linear epitopes recognized by the mAbs were defined by IFA and peptide ELISA. The results showed that mAb 10F4 recognized an epitope located in the N-terminal 6-12 amino acids of the M2 peptide, and the mAbs 10D9, 1E2, 4B5, and 5G10 recognized the epitopes located in the C-terminal 62-77 amino acids of the M2 peptide. Importantly, mAb 10D9 recognized the M2 protein of H1-H13 IAV subtypes, which stained M2 protein located on the membrane of host cells and could be applied in immunoprecipitation and immunohistochemistry assays. The mAb 10D9 which recognizes the universal M2 epitope of IAVs will be a useful tool for studies on the function of IAV M2 protein and for the development of vaccines or detection methods for IAV infection.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Vírus da Influenza A/imunologia , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/imunologia , Animais , Mapeamento de Epitopos , Epitopos/imunologia , Escherichia coli/genética , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/imunologia
5.
J Clin Nurs ; 27(19-20): 3522-3529, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29945293

RESUMO

AIMS AND OBJECTIVES: To compare and evaluate the reliability, validity, feasibility, clinical utility, and nurses' preference of the Premature Infant Pain Profile-Revised, the Neonatal Pain, Agitation, and Sedation Scale, and the Neonatal Infant Acute Pain Assessment Scale used for procedural pain in ventilated neonates. BACKGROUND: Procedural pain is a common phenomenon but is undermanaged and underassessed in hospitalised neonates. Information for clinician selecting pain measurements to improve neonatal care and outcomes is still limited. DESIGN: A prospective observational study was used. METHODS: A total of 1,080 pain assessments were made at 90 neonates by two nurses independently, using three scales viewing three phases of videotaped painful (arterial blood sampling) and nonpainful procedures (diaper change). Internal consistency, inter-rater reliability, discriminant validity, concurrent validity and convergent validity of scales were analysed. Feasibility, clinical utility and nurses' preference of scales were also investigated. RESULTS: All three scales showed excellent inter-rater coefficients (from 0.991-0.992) and good internal consistency (0.733 for the Premature Infant Pain Profile-Revised, 0.837 for the Neonatal Pain, Agitation, and Sedation Scale and 0.836 for the Neonatal Infant Acute Pain Assessment Scale, respectively). Scores of painful and nonpainful procedures on the three scales changed significantly across the phases. There was a strong correlation between the three scales with adequate limits of agreement. The mean scores of the Neonatal Pain, Agitation, and Sedation Scale for feasibility and utility were significantly higher than those of the Neonatal Infant Acute Pain Assessment Scale, but not significantly higher than those of the Premature Infant Pain Profile-Revised. The Neonatal Pain, Agitation, and Sedation Scale was mostly preferred by 55.9% of the nurses, followed by the Neonatal Infant Acute Pain Assessment Scale (23.5%) and the Premature Infant Pain Profile-Revised (20.6%). CONCLUSIONS: The three scales are all reliable and valid, but the Neonatal Pain, Agitation, and Sedation Scale and the Neonatal Infant Acute Pain Assessment Scale perform better in reliability. The Neonatal Pain, Agitation, and Sedation Scale appears to be a better choice for frontier nurses to assess procedural pain in ventilated neonates based on its good feasibility, utility and nurses' preference. RELEVANCE TO CLINICAL PRACTICE: Choosing a valid, reliable, feasible and practical measurement is the key step for better management of procedural pain for ventilated newborns. Using the right and suitable tool is helpful to accurately identify pain, ultimately improve the neonatal care and outcomes.


Assuntos
Dor Aguda/diagnóstico , Medição da Dor , Dor Processual/diagnóstico , Estudos de Viabilidade , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Respiração Artificial
6.
Front Med (Lausanne) ; 11: 1379333, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618195

RESUMO

Introduction: Gut dysbiosis may play a pivotal role in the pathogenesis of cirrhosis and the severity of complications. Numerous studies have investigated the probiotics as treatments for cirrhosis. However, there is still a lack of definitive evidence confirming the beneficial effects of probiotics on cirrhosis. Methods: Databases including PubMed, Embase, Web of Science, and the Cochrane Library were systematically searched for randomized controlled trials that compared the effects of probiotic intervention and control treatments, including placebo, no treatment, and active control, on cirrhosis, published from inception to February 2024. Outcomes included hepatic encephalopathy (HE) reversal, safety and tolerability of probiotics, liver function, quality of life, and other cirrhotic-related outcomes. A meta-analysis was conducted to synthesize evidence. Results: Thirty studies were included. The quantitative synthesis results showed that compared with the control group, probiotics significantly reverse minimal hepatic encephalopathy (MHE) (risk ratio [RR] 1.54, 95% confidence interval [CI] 1.03 to 2.32) and improve HE (RR 1.94, 95% CI 1.24 to 3.06). Additionally, probiotics demonstrated higher safety and tolerability by causing a lower incidence of serious adverse events (RR 0.71, 95% CI 0.58 to 0.87). Probiotics could potentially improve liver function by reducing the Model for End-Stage Liver Disease (MELD) scores (standardized mean difference [SMD] -0.57, 95% CI -0.85 to -0.30), and displayed favorable changes in quality of life (SMD 0.51, 95% CI 0.27 to 0.75) and gut flora (SMD 1.67, 95% CI 1.28 to 2.06). Conclusion: This systematic review and meta-analysis offers compelling evidence that probiotics are beneficial for cirrhosis by demonstrating reversal of HE, potential for liver function improvements, enhancements in quality of life, and regulation of gut dysbiosis. Furthermore, the apparent safety profile suggests that probiotics are a promising intervention for treating cirrhosis. Clinical trial registration number: CRD42023478380.

7.
Front Public Health ; 10: 797274, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211441

RESUMO

Using data from the 2018 Chinese Family Panel Studies (CFPS), based on the mood-congruent theory, this study aims to explore the mechanisms of mental health on job satisfaction from the internal perspective (psychological capital) and external perspective (social capital). The results showed that (1) the two components of mental health have different effects on job satisfaction. The positive component of mental health had a positive effect on job satisfaction, while the negative component of mental health had a negative effect on job satisfaction; (2) Psychological capital and social capital play a mediating role in the relationship between mental health and job satisfaction. (3) After considering the potential endogenous problems between mental health and job satisfaction and conducting additional robustness analysis, including changing dependent variable and changing independent variable, our main results and influence mechanisms are remain robust and reliable. With the emergence of an increasingly competitive knowledge economy era, employees' mental health plays an important role in job satisfaction. Thus, it is imperative for managers to enhance employees' job satisfaction and better implement humanistic management by nurturing employees' psychological and social capital through the mental health.


Assuntos
Capital Social , Afeto , Povo Asiático , Humanos , Satisfação no Emprego , Saúde Mental
8.
PLoS One ; 17(2): e0263674, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35148330

RESUMO

The effects of social networks on the relationship between internationalization and firm performance have been well documented in the international literature, and two dimensions of social networks have also been identified: business ties and political ties. However, few efforts have been made to examine whether there are different mechanisms of business ties and political ties. Based on social network theory and boundary spanning theory, we build a model of a dual mechanism of social networks, and the business ties and political ties of social networks that correspond with information processing and the external representation of boundary spanning theory. Using the data of Chinese listed companies in 2005-2013 and 2013-2017 to test the model, the results indicate that (1) in the relationship between internationalization and firm performance, the role of social networks has a dual mechanism. (2) Business ties play a mediating role in the relationship between internationalization and firm performance. Business ties are conducive to a company's information acquisition and knowledge sharing and play the role of information processing. (3) Political ties play a U-shaped moderating role in the relationship between internationalization and firm performance and assume the role of external representation.


Assuntos
Comércio , Rede Social , China , Pesquisa Empírica , Humanos , Internacionalidade
9.
Artigo em Inglês | MEDLINE | ID: mdl-36554955

RESUMO

Organizations and individuals are unprepared for an unexpected outbreak of COVID-19. While most of the literature focuses on improvised reactions at the organizational level, this paper focuses on understanding improvised reactions at the individual level. This paper draws on previous research applying improvisation to the field of consumer behavior and introduces consumer knowledge acquisition as a mediating variable and tightness-looseness culture as a moderating variable from the perspective of mixed emotions of awe and anxiety to explain the mechanism of consumers with mixed emotions of awe and anxiety on improvisation behavior based on the environment of a COVID-19 outbreak. Data from 330 participants in Study 1 examined the effect of mixed emotions of awe and anxiety on improvisation behavior through knowledge acquisition, and data from 434 participants in Study 2 examined the moderating effect of relaxed culture. The findings suggest that consumers with mixed emotions report a higher willingness to acquire knowledge and report higher levels of improvisational behavior. Consumers behaved differently in different environments. Consumers with mixed emotions responded more strongly to improvisation in the loose-culture environment than in the tight-culture environment, and the mixed emotions of awe and anxiety had a positive effect on individual consumers' improvisational behavior through the mediating role of knowledge acquisition.


Assuntos
COVID-19 , Emoções , Humanos , Comportamento do Consumidor , COVID-19/epidemiologia , Afeto , Ansiedade/epidemiologia
10.
Front Psychol ; 12: 786372, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899538

RESUMO

In the era of mobile internet, newsfeed advertising, which is most applicable to consumption scenarios that involve mobile devices, has become a core driving force in advertising. The rapid advancement of technology with respect to newsfeed advertising has not only reshaped the green consumption sector but has also had significant impacts on consumer psychology and behavior. When faced with highly social green newsfeed advertising, consumers are receptive to different degrees, which ultimately affects their receptivity to new green products. Through an experiment and a questionnaire, we find the following: (1) Consumers prefer new green products advertised through high-sociality green newsfeed advertisements more than those advertised with low-sociality ads. (2) Receptivity to green advertising can mediate the impact of the sociality of newsfeed advertising on consumer adoption of new green products. (3) The aforementioned direct effect and mediating effect are also affected by consumers' green involvement. Our paper has both theoretical and practical significance; that is, we contribute to the research on the impacts of the sociality of green advertising on the psychological mechanisms underlying consumer adoption of new green products. Additionally, we provide managerial recommendations for the future development of green newsfeed advertising and for improvements in consumer impressions of green consumption.

11.
Monoclon Antib Immunodiagn Immunother ; 36(2): 57-61, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28409665

RESUMO

Premembrane (prM) is a viral protein of flavivirus, which is important for the generation of infectious virion and for virus infection to the host. However, the biological properties and function of the prM of Avian Tembusu virus (ATMUV) have scarcely been studied to date. Monoclonal antibodies (mAbs) are a powerful tool for functional analysis of viral protein. To produce a mAb against prM protein of ATMUV, the prM gene sequence was amplified by reverse transcription polymerase chain reaction (RT-PCR) and cloned into the prokaryotic expression vector pET-28a (+). The recombinant prM protein was successfully expressed in BL21 (DE3). Using the purified prM as immunogen in mice, three hybridoma cells secreting mAbs against prM protein were obtained. These mAbs showed a strong reaction with ATMUV-infected DF-1 cells and pEGFP-C3-prM transfected 293-T cells in both Western blotting analysis and immunofluorescence assay. The mAbs developed in this study will be useful tools for analysis of the prM protein functions on ATMUV infection and the interaction between prM and its host molecules.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Doenças das Aves/virologia , Infecções por Flavivirus/veterinária , Flavivirus/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/química , Western Blotting/métodos , Linhagem Celular , Clonagem Molecular , Patos/virologia , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Fibroblastos/virologia , Flavivirus/genética , Flavivirus/isolamento & purificação , Infecções por Flavivirus/virologia , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Células HEK293 , Humanos , Hibridomas/imunologia , Imunização Secundária/métodos , Camundongos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Baço/citologia , Baço/imunologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/genética
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