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2.
J Cancer Educ ; 37(3): 857-871, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35098479

RESUMO

Summer internships serve important roles in training the next generation of biomedical researchers and healthcare providers through laboratory and clinical experiences that excite trainees about these fields and help them make informed decisions about career paths. The SARS-CoV-2 (COVID) pandemic and associated physical distancing restrictions precluded implementation of traditional in-person summer curricula and led to the cancellation of many internships across the USA. COVID-related disruptions also created opportunities for trainees to engage in remote research, become proficient in online learning platforms, and explore multidisciplinary topics. These skills are highly relevant to trainees as virtual interfaces occupy an increasingly mainstream role in their professional paths. The response to the COVID pandemic required real-time adaptations at all levels for major biomedical institutions including the University of Maryland Baltimore (UMB). Pivoting summer programs to a virtual format as part of this response provided a "teachable moment" to expose trainees to the innovation and resilience that are essential components of the biomedical profession. UMB summer programs, which span diverse biomedical disciplines from cancer research to diabetes, consolidated resources and identified mentors with online research projects to develop a robust virtual curriculum. Herein, data from a cancer-focused internship illustrate the collaborative adaptations to established components and creation of new learning modules in the transition to, and implementation of, online training. Outcomes are presented in the context of the COVID pandemic and significant societal issues that arose in the summer of 2020. The utility of virtual components and their impact on future programs is discussed.


Assuntos
COVID-19 , Educação a Distância , Neoplasias , COVID-19/epidemiologia , Currículo , Humanos , Neoplasias/epidemiologia , Pandemias , SARS-CoV-2
3.
J Virol ; 75(13): 6095-106, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11390611

RESUMO

Hepatitis C virus (HCV), a major cause of liver disease worldwide, is frequently resistant to the antiviral alpha interferon (IFN). The HCV nonstructural 5A (NS5A) protein has been implicated in HCV antiviral resistance in many studies. NS5A antagonizes the IFN antiviral response in vitro, and one mechanism is via inhibition of a key IFN-induced enzyme, the double-stranded-RNA-activated protein kinase (PKR). In the present study we determined if NS5A uses other strategies to subvert the IFN system. Expression of full-length NS5A proteins from patients who exhibited a complete response (FL-NS5A-CR) or were nonresponsive (FL-NS5A-NR) to IFN therapy in HeLa cells had no effect on IFN induction of IFN-stimulated gene factor 3 (ISGF-3). Expression of mutant NS5A proteins lacking 110 (NS5A-DeltaN110), 222 (NS5A-DeltaN222), and 334 amino-terminal amino acids and mutants lacking 117 and 230 carboxy-terminal amino acids also had no effect on ISGF-3 induction by IFN. Expression of FL-NS5A-CR and FL-NS5A-NR did not affect IFN-induced STAT-1 tyrosine phosphorylation or upregulation of PKR and major histocompatibility complex class I antigens. However, NS5A expression in human cells induced interleukin 8 (IL-8) mRNA and protein, and this effect correlated with inhibition of the antiviral effects of IFN in an in vitro bioassay. NS5A induced transcription of a reporter gene driven by the IL-8 promoter, and the first 133 bp of the IL-8 promoter made up the minimal domain required for NS5A transactivation. NS5A-DeltaN110 and NS5A-DeltaN222 stimulated the IL-8 promoter to higher levels than did the full-length NS5A protein, and this correlated with increased nuclear localization of the proteins. Additional mutagenesis of the IL-8 promoter suggested that NF-kappaB and AP-1 were important in NS5A-DeltaN222 transactivation in the presence of tumor necrosis factor alpha and that NF-IL-6 was inhibitory to this process. This study suggests that NS5A inhibits the antiviral actions of IFN by at least two mechanisms and provides the first evidence for a biological effect of the transcriptional activity of the NS5A protein. During HCV infection, viral proteins may induce chemokines that contribute to HCV antiviral resistance and pathogenesis.


Assuntos
Hepacivirus/efeitos dos fármacos , Interferons/antagonistas & inibidores , Interleucina-8/biossíntese , Proteínas não Estruturais Virais/fisiologia , Sequência de Bases , Proteínas de Ligação a DNA/metabolismo , Resistência Microbiana a Medicamentos , Células HeLa , Humanos , Interleucina-8/genética , Dados de Sequência Molecular , Fosforilação , Regiões Promotoras Genéticas , RNA Mensageiro/análise , Fator de Transcrição STAT1 , Transdução de Sinais , Transativadores/metabolismo , Ativação Transcricional , Fator de Necrose Tumoral alfa/farmacologia
4.
Virology ; 281(1): 124-37, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11222103

RESUMO

The dsRNA-dependent protein kinase, PKR, is a key component of interferon (IFN)-mediated anti-viral action and is frequently inhibited by many viruses following infection of the cell. Recently, we have demonstrated that IFN and PKR can sensitize cells to apoptosis predominantly through the FADD/caspase-8 pathway (S. Balachandran, P. C. Roberts, T. Kipperman, K. N. Bhalla, R. W. Compans, D. R. Archer, and G. N. Barber. (2000b) J. Virol. 74, 1513-1523). Given these findings, it is thus plausible that rather than specifically target IFN-inducible genes such as PKR, viruses could also subvert the mechanisms of IFN action, in part, at locations that could block the apoptotic cascade. To explore this possibility, we analyzed whether the poxvirus caspase-8 inhibitor, CrmA, was able to inhibit IFN or PKR/dsRNA-mediated apoptosis. Our findings indicated that CrmA could indeed inhibit apoptosis induced by both viral infection and dsRNA without blocking PKR activity or inhibiting IFN signaling. In contrast HCV-encoded NS5A, a putative inhibitor of PKR, did not appear to inhibit cell death mediated by a number of apoptotic stimuli, including IFN, TRAIL, and etoposide. Our data imply that viral-encoded inhibitors of apoptosis, such as CrmA, can block the innate arms of the immune response, including IFN-mediated apoptosis, and therefore potentially constitute an alternative family of inhibitors of IFN action in the cell.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Apoptose/efeitos dos fármacos , Hepacivirus , Interferons/farmacologia , Serpinas/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais , Substituição de Aminoácidos , Proteínas Reguladoras de Apoptose , Western Blotting , Proteínas de Transporte/fisiologia , Caspase 8 , Caspase 9 , Inibidores de Caspase , Caspases/metabolismo , Inibidores de Cisteína Proteinase/metabolismo , Doxiciclina/farmacologia , Etoposídeo/farmacologia , Proteína de Domínio de Morte Associada a Fas , Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Interferons/antagonistas & inibidores , Cinética , Glicoproteínas de Membrana/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , RNA de Cadeia Dupla/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF , Tetraciclina/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Vírus da Estomatite Vesicular Indiana/fisiologia , eIF-2 Quinase/antagonistas & inibidores , eIF-2 Quinase/metabolismo , Receptor fas/metabolismo
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