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1.
J Obstet Gynecol Neonatal Nurs ; 44(1): 77-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25580851

RESUMO

OBJECTIVE: To evaluate the baseline knowledge and knowledge gained of nurses, nursing students, midwives, and nurse practitioners who completed Breastfeeding Basics, an online educational program. DESIGN: This study reports on an anonymous evaluation of an online breastfeeding education program developed and maintained to promote evidence-based breastfeeding practice. PARTICIPANTS: Included in the study were 3736 nurses, 728 nurse practitioners/midwives, and 3106 nursing students from the United States who completed ≥ one pretest or posttest on the Breastfeeding Basics website between April 1999 and December 31, 2011. METHODS: Baseline scores were analyzed to determine if nurses' baseline knowledge varied by selected demographic variables such as age, gender, professional level, personal or partner breastfeeding experience, and whether they were required to complete the website for a job or school requirement and to determine knowledge gaps. Pretest and posttest scores on all modules and in specific questions with low pretest scores were compared as a measure of knowledge gained. RESULTS: Lower median pretest scores were found in student nurses (71%), males (71%), those required to take the course (75%), and those without personal breastfeeding experience (72%). The modules with the lowest median pretest scores were Anatomy/Physiology (67%), Growth and Development of the Breastfed Infant (67%), the Breastfeeding Couple (73%), and the Term Infant with Problems (60%). Posttest scores in all modules increased significantly (p < .001). CONCLUSION: Breastfeeding Basics was used by a large number of nurses and nursing students. Gaps exist in nurses' breastfeeding knowledge. Knowledge improved in all areas based on comparison of pretest and posttest scores.


Assuntos
Aleitamento Materno/métodos , Instrução por Computador/métodos , Educação Continuada em Enfermagem/métodos , Conhecimentos, Atitudes e Prática em Saúde , Internet , Feminino , Humanos , Capacitação em Serviço/métodos , Masculino , Pesquisa em Educação em Enfermagem , Apoio Social , Estados Unidos
4.
Neuropsychologia ; 46(7): 1954-64, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18329672

RESUMO

Episodic memory impairment is commonly observed in patients with epilepsy associated with mesial temporal sclerosis (MTS). Prospective memory (PM) is a set cognitive abilities that allow future performance of a present intention, in response to time- or event-based evocation cues, that trigger the intended action at the appropriate time. PM has not been evaluated in mesial temporal sclerosis. We evaluated the role of right and left hippocampal lesions on performance in both the retrospective and prospective PM components in patients with epilepsy secondary to mesial temporal sclerosis and correlated with performance in traditional neuropsychological tests, as well as with self-perception of memory impairment. We tested the hypotheses that a hippocampal lesion impacts on the prospective components of PM, and that a left-sided lesion had a greater impact on performance in the prospective component of PM than a right-sided lesion. We evaluated PM in 26 patients with right MTS, 22 left MTS patients, and 26 age-gender and education matched controls. The prospective component of PM was impaired in both patient groups, with both a lesion (patients performed significantly worse in the PM battery) and laterality effect (left MTS patients performed significantly worse than right MTS patients in the PM battery). Performance in the prospective component of the PM battery correlated with long-term delay performance in episodic verbal memory and self-perception of memory impairment in the left MTS group. The retrospective component was impaired in left MTS patients. Impaired performance was not accounted for solely by depression, anxiety or an antiepileptic drug effect. We conclude that mesial temporal lobe structures, including the hippocampus, play an important role in both the prospective and retrospective components of PM processes in tasks involving long delay intervals.


Assuntos
Epilepsia do Lobo Temporal/fisiopatologia , Lobo Frontal/fisiopatologia , Lateralidade Funcional/fisiologia , Hipocampo/fisiopatologia , Transtornos da Memória/fisiopatologia , Testes Neuropsicológicos/estatística & dados numéricos , Adolescente , Adulto , Atenção/fisiologia , Sinais (Psicologia) , Aprendizagem por Discriminação , Epilepsia do Lobo Temporal/diagnóstico , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/patologia , Humanos , Sistema Límbico/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/diagnóstico , Pessoa de Meia-Idade , Reconhecimento Psicológico/fisiologia , Esclerose/fisiopatologia
5.
J. bras. psiquiatr ; 56(2): 120-126, 2007. tab
Artigo em Português | LILACS | ID: lil-465454

RESUMO

OBJETIVO: Procuramos analisar os aspectos cognitivos e metodológicos envolvidos na avaliação da noção de intervalos de tempo, verificando os aspectos cognitivos envolvidos durante a sua execução, e apontar a relevância, aplicabilidade e sensibilidade dessa avaliação no exame neuropsicológico. MÉTODOS: Realizou-se revisão bibliográfica abrangendo artigos e pesquisas das literaturas nacional e internacional no período de 1990 a 2005. RESULTADOS: Encontraram-se 13 diferentes estudos. São controversas as discussões acerca de teorias sobre a noção de tempo. Os estudos podem ser agrupados de acordo com duas perspectivas diferentes: a teoria da contagem atencional, de grande utilização por pesquisadores americanos, e a teoria do relógio interno, muito abordada por estudiosos franceses que se diferem tanto em relação à abordagem teórica quanto à metodológica. CONCLUSÕES: Ambos os grupos de pesquisa, americanos e franceses, retratam a relevância da aplicação dos testes de estimativa, reprodução e produção de tempo no estudo das funções executivas.


OBJECTIVE: We tried to analyze the cognitive and methodological aspects involved in the evaluation of time intervals notion, verifying the cognitive aspects involved during your execution, and to point the relevance, applicability and sensibility of this evaluation in the neuropsychologic exam. METHODS: Bibliographical revision was accomplished including articles and researches of the national and international literature in the period of 1990 to 2005. RESULTS: Were found 13 different researches. The discussions concerning theories about the time notion are controversial. These studies can be grouped into two different perspectives: the attentional counter theory, used by American researchers, and the internal clock theory, very boarded by French studious, that are differed in relation to the theoretical and to the methodological approaches. CONCLUSIONS: Both research groups, Americans and French, show the relevance of the application of the time-interval estimation tests, reproduction and production in the study of the executive functions.

6.
Psico USF ; 11(1): 95-102, jan.-jun. 2006. ilus
Artigo em Português | Index Psicologia - Periódicos | ID: psi-34072

RESUMO

Este trabalho objetivou avaliar o índice de sintomas depressivos, bem como sua distribuição por gênero e série, dos alunos de um colégio particular, da cidade de Uberaba-MG, no final do segundo e do terceiro ano do Ensino Médio e no 'cursinho pré-vestibular', próximo ao concurso vestibular. Foram avaliados 791 estudantes, utilizando o questionário SRQ-20 - Self Reporting Questionnaire, um instrumento desenvolvido pela Organização Mundial da Saúde com 20 questões, que serve para rastrear e avaliar a ocorrência de transtornos mentais comuns, dentre eles a depressão, na população geral. Foram encontradas duas vezes mais sintomatologia depressiva no sexo feminino e um aumento do indicativo de depressão de acordo com o progresso acadêmico dos sujeitos. Conclui-se que existe a presença de sintomas depressivos em 45,7 por cento da amostra, com maior prevalência de casos no sexo feminino. Foi sugerido acompanhamento psicológico aos alunos(AU)


Assuntos
Humanos , Masculino , Feminino , Ensino Fundamental e Médio , Depressão , Adolescente , Escolha da Profissão
7.
Psico USF ; 11(1): 95-102, jan.-jun. 2006. ilus
Artigo em Português | LILACS | ID: lil-483850

RESUMO

Este trabalho objetivou avaliar o índice de sintomas depressivos, bem como sua distribuição por gênero e série, dos alunos de um colégio particular, da cidade de Uberaba-MG, no final do segundo e do terceiro ano do Ensino Médio e no 'cursinho pré-vestibular', próximo ao concurso vestibular. Foram avaliados 791 estudantes, utilizando o questionário SRQ-20 - Self Reporting Questionnaire, um instrumento desenvolvido pela Organização Mundial da Saúde com 20 questões, que serve para rastrear e avaliar a ocorrência de transtornos mentais comuns, dentre eles a depressão, na população geral. Foram encontradas duas vezes mais sintomatologia depressiva no sexo feminino e um aumento do indicativo de depressão de acordo com o progresso acadêmico dos sujeitos. Conclui-se que existe a presença de sintomas depressivos em 45,7 por cento da amostra, com maior prevalência de casos no sexo feminino. Foi sugerido acompanhamento psicológico aos alunos.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Escolha da Profissão , Depressão , Ensino Fundamental e Médio
8.
Clin Diagn Lab Immunol ; 8(5): 913-21, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11527803

RESUMO

Improvement of serologic assays for detection of antibodies against human herpesvirus 8 (HHV-8) is critical to better understand its epidemiology and biology. We produced the HHV-8 latent (ORF73) and lytic (ORF65, K8.1, and glycoprotein B) antigens in the Semliki Forest virus system and evaluated their performance in immunofluorescence assays (IFAs) and enzyme-linked immunosorbent assays (ELISAs). These assays were compared with other latent antigen-based assays, including an IFA based on primary effusion lymphoma (PEL) cells and an ELISA based on bacterially expressed ORF73 antigen, as well as with other lytic antigen-based assays, including an IFA based on induced PEL cells, a commercial ELISA based on purified virions, and ELISAs based on K8.1- and ORF65-derived oligopeptides. We used a panel of 180 serum specimens obtained from three groups expected to have high, intermediate, and low HHV-8 prevalences. Using three different evaluation methods, we found that (i) the performances of the lytic antigen-based ELISAs were almost equivalent, (ii) the lytic antigen-based assays were more sensitive than the latent antigen-based assays, and (iii) in general, IFAs were more sensitive than ELISAs based on the same open reading frame. We also found that serum specimens from healthy individuals contained antibodies cross-reactive with HHV-8 glycoprotein B that can potentially cause false-positive reactions in lytic PEL-based IFAs. Although this is not a substantial problem in most epidemiologic studies, it may confound the interpretation of data in studies that require high assay specificity. Because the K8.1-based IFA provides sensitivity similar to that of lytic PEL-based IFAs and improved specificity, it can be a useful alternative to the PEL-based IFAs.


Assuntos
Anticorpos Antivirais/biossíntese , Infecções por Herpesviridae/sangue , Herpesvirus Humano 8/imunologia , Proteínas Virais , Anticorpos Antivirais/metabolismo , Antígenos Virais/biossíntese , Linhagem Celular , Ensaio de Imunoadsorção Enzimática/métodos , Imunofluorescência/métodos , Glicoproteínas/análise , Infecções por Herpesviridae/diagnóstico , Herpesvirus Humano 8/isolamento & purificação , Humanos , Proteínas Nucleares/biossíntese , Vírus da Floresta de Semliki/imunologia , Proteínas do Envelope Viral/imunologia
9.
Clin Diagn Lab Immunol ; 7(3): 427-35, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10799457

RESUMO

Several assays have been developed for detection of immunoglobulin G antibodies to Human herpesvirus 8 (HHV-8), including immunofluorescence assays (IFAs) and enzyme-linked immunosorbent assays (ELISAs). However, the specificity and sensitivity of these assays are not completely defined due to the lack of a "gold standard." Although IFAs based on primary effusion lymphoma (PEL) cell lines are used widely, the assays can be confounded by nonspecific reactions against cellular components and potential cross-reaction with antibodies against other herpesviruses. To provide more reliable IFAs, we established recombinant Semliki Forest viruses (rSFVs) expressing the HHV-8-specific proteins ORF73 and K8.1 and used BHK-21 cells infected with these rSFVs for IFA (ORF73-IFA and K8.1-IFA). Expression of the HHV-8-specific proteins at very high levels by the rSFV system allowed easy scoring for IFA and thereby increased specificity. The rSFV system also allowed detection of antibodies against glycosylation-dependent epitopes of K8.1. Titers measured by rSFV-based IFAs and PEL-based IFAs correlated well (correlation coefficients of >0.9), and concordances of seroreactivities between rSFV-based and PEL-based IFAs were >97% (kappa > 0.93). K8.1-IFA was more sensitive than either ORF73-IFA or peptide ELISAs. Using PEL-based lytic IFA as a reference assay, the sensitivity and specificity of K8.1-IFA were estimated to be 94 and 100%, respectively. HHV-8 prevalences determined by K8.1-IFA among the human immunodeficiency virus (HIV)-positive (HIV(+)) Kaposi's sarcoma (KS) patients, HIV(+) KS(-) patients, and healthy controls were 100, 65, and 6.7%, respectively, which were consistent with prior reports. Therefore, our rSFV-based IFAs may provide a specific and sensitive method for use in epidemiology studies. In addition, they will provide a basis for further development of diagnostic tests for HHV-8 infection.


Assuntos
Glicoproteínas/análise , Infecções por Herpesviridae/diagnóstico , Herpesvirus Humano 8/isolamento & purificação , Proteínas Nucleares/análise , Fosfoproteínas , Proteínas Virais , Animais , Anticorpos Antivirais/análise , Linhagem Celular , Cricetinae , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Epitopos/imunologia , Epitopos/metabolismo , Imunofluorescência , Regulação Viral da Expressão Gênica , Glicoproteínas/genética , Glicoproteínas/imunologia , Glicosilação , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/imunologia , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/imunologia , Humanos , Rim/citologia , Biologia Molecular/métodos , Biologia Molecular/normas , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Coelhos , Vírus da Floresta de Semliki , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
10.
Genet Test ; 4(4): 393-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11216665

RESUMO

During a D1S80 population study conducted for databasing purposes in the New York City Ashkenazi Jewish population, eight out of 96 samples were typed with a band corresponding to the position of a #15 allele. In seven of the eight samples, three bands appeared. Further investigation was needed to explain the high frequency of an allele considered so rare that it is not included in the commercially provided allelic ladder. After extraction of the putative D1S80 15-repeat amplicon band from the 6% polyacrylamide genotyping gel, the amplicon bands were reamplified with D1S80 primers. After retyping as putative 15 alleles, these samples underwent Southern hybridization with a D1S80 locus-specific probe followed by DNA sequence analysis. Sequence analysis revealed that these bands did not arise from true D1S80 15 alleles. However, the PCR product was of a size that fell within the allelic ladder region corresponding to the 15 band and contained end sequences with strong homology to the D1S80 primers. An alignment search of the sequenced product revealed that a portion of the amplicons contained 72% identity to a known gene. These results emphasize the importance of sequencing analysis when questions arise about the authenticity of an allele.


Assuntos
Alelos , Marcadores Genéticos/genética , Judeus/genética , Southern Blotting , Sequência Consenso/genética , Primers do DNA , Sondas de DNA , Eletroforese em Gel de Poliacrilamida , Frequência do Gene/genética , Genótipo , Análise Heteroduplex , Humanos , New York , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Análise de Sequência de DNA
11.
J Theor Biol ; 199(3): 297-309, 1999 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-10433894

RESUMO

Dictyostelium discoideum slugs show a pronounced thermotaxis. We have modelled the motion of the D. discoideum slug in the absence and in the presence of a thermal gradient. Our model is an extension of the hybrid cellular automata/partial differential equation model, as formulated by Savill and Hogeweg [J. theor. Biol., (1997) 184, 229-235]. The modelled slugs maintain their shape and crawl, with a velocity depending on slug size, as found in experiments. Moreover, they show thermotactic behaviour: independent of the initial orientation, after some transient process, the slugs start moving along the temperature gradient. The slug behaviour in our model is due to the collective behaviour of the amoebae. Individual amoebae can neither respond to a shallow temperature gradient, nor show differentiation in motion velocity. The behaviour is achieved by a modification of the cyclic AMP waves: differences in temperature alter the excitability of the cell, and thereby the shape of the cyclic AMP wave. Chemotaxis towards cyclic AMP causes the slug to turn. We show that the mechanism still functions at very low signal-to-noise ratios. Copyright 1999 Academic Press.

12.
Int J Legal Med ; 111(5): 273-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9728757

RESUMO

Allele frequencies were determined for the VNTR locus D1S80 in Hasidic and non-Hasidic Ashkenazi New York City Jewish subpopulations. Samples were amplified via the polymerase chain reaction and underwent genotyping using polyacrylamide gel electrophoresis. In the Hasidic population 14 alleles were observed as opposed to 19 alleles in the non-Hasidic community. Both populations were tested for Hardy-Weinberg equilibrium. The frequency data obtained can be used for comparison to other populations and for allele and genotype frequency estimates in genetic marker profiling of evidentiary specimens.


Assuntos
Frequência do Gene , Judeus/genética , Alelos , Genética Populacional , Genótipo , Humanos , Cidade de Nova Iorque , Reação em Cadeia da Polimerase
14.
Artigo em Inglês | MEDLINE | ID: mdl-8797679

RESUMO

Kaposi's sarcoma (KS) is a multifocal vascular lesion characterized by abnormal proliferation of endothelial-like KS cells linked to a pronounced leukocyte infiltration. KS lesions contain novel herpes-like DNA sequences, KSHV, hypothesized to originate from the viral pathogen for KS. Using cultured KS cells that retain the KSHV sequences, diverse signals, including tumor necrosis factor alpha, interleukin (IL) 1 beta, polyinosinic acid/polycytidylic acid and lipopolysaccharide, induced the expression of the cytokine IL-6 and cellular adhesion molecules involved in leukocyte recruitment, including vascular adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). The thiol-antioxidant pyrrolidine dithiocarbamate (PDTC) selectively inhibited > 90% of the activation of nuclear factor kappa B-like DNA binding activity in KS cells. PDTC also reduced by > 85% induced levels of VCAM-1 and IL-6 at the mRNA, protein, and functional levels in KS cells. In contrast, PDTC did not inhibit the induced expression of either ICAM-1 or E-selectin. These studies show that PDTC differentially modulates the expression of inflammatory response genes in KS cells that contain KSHV, suggesting that reduction-oxidation-sensitive events are involved in the regulation of these genes. These studies also suggest that thiol-antioxidants such as PDTC may play a potentially therapeutic role in the treatment of KS by preventing induction of specific inflammatory response genes that may be involved in the pathogenesis of KS.


Assuntos
Antioxidantes/farmacologia , Infecções por HIV/complicações , Pirrolidinas/farmacologia , Sarcoma de Kaposi/genética , Tiocarbamatos/farmacologia , Animais , Sequência de Bases , Biópsia , Northern Blotting , Southern Blotting , Células Cultivadas , Sondas de DNA , Selectina E/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Infecções por HIV/genética , Humanos , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/efeitos dos fármacos , Interleucina-6/antagonistas & inibidores , Masculino , Dados de Sequência Molecular , NF-kappa B/efeitos dos fármacos , Reação em Cadeia da Polimerase , RNA Viral/metabolismo , Sarcoma de Kaposi/metabolismo , Pele/patologia , Molécula 1 de Adesão de Célula Vascular/efeitos dos fármacos
15.
Muscle Nerve ; 19(3): 350-4, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8606700

RESUMO

Electrodiagnostic findings of fibrillations and positive sharp waves in the lumbosacral paraspinals in patients without previous back surgery has been generally considered to be abnormal, consistent with posterior rami denervation. In some cases, it is the only abnormality on the electromyographic examination. This study was undertaken to determine the prevalence of abnormal spontaneous activity in lumbosacral paraspinals in asymptomatic individuals. Nine (14.5%) of 62 subjects studied had positive sharp waves or fibrillations noted on the needle examination of bilateral lumbosacral paraspinal muscles. There was a significant increase in the prevalence of abnormal activity with increasing age. This suggests that caution should be taken in attributing radiculopathy as the etiology of low back pain when electromyographic lumbosacral paraspinal abnormalities are the only positive findings in the middle-aged or older individual.


Assuntos
Vértebras Lombares , Doenças Neuromusculares/epidemiologia , Doenças da Coluna Vertebral/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Músculo Esquelético/fisiopatologia , Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/fisiopatologia , Prevalência , Radiculopatia/diagnóstico , Radiculopatia/epidemiologia , Radiculopatia/fisiopatologia , Doenças da Coluna Vertebral/diagnóstico , Doenças da Coluna Vertebral/fisiopatologia
16.
Lancet ; 346(8990): 1601-2, 1995 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-7500753

RESUMO

We explored a possible route of transmission of Kaposi's-sarcoma-associated herpes virus (KSHV) with nested and unnested PCR techniques. We looked for KSHV DNA sequences in semen of HIV-positive homosexual men and HIV-negative healthy semen donors. With unnested primers we found KSHV sequences in 21 of 33 (64%) homosexual men and in none of 30 healthy donors. With a nested PCR assay, 30 of 33 (91%) specimens from the homosexual men and 7 of 30 (23%) specimens from healthy donors had detectable KSHV sequences. Over 5 years of follow-up, 13 of 30 KSHV-positive homosexual men (43%) developed KS compared with none of the 3 KSHV-negative homosexual men.


Assuntos
Infecções por HIV/complicações , Herpesviridae/isolamento & purificação , Homossexualidade Masculina , Sarcoma de Kaposi/virologia , Sêmen/virologia , DNA Viral/genética , Infecções por HIV/virologia , Soronegatividade para HIV , Herpesviridae/genética , Humanos , Masculino , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Sarcoma de Kaposi/etiologia , Análise de Sequência de DNA
17.
Antiviral Res ; 28(1): 1-11, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8585756

RESUMO

The effects of (+)-beta-D-dioxolane-cytosine ((+)-D-beta-DOC), (-)-beta-L-dioxolane-cytosine ((-)-L-beta-DOC), (+)-beta-D-oxathiolane-cytosine ((+)-D-beta-OTC), (-)-beta-L-oxathiolane-cytosine ((-)-L-beta-OTC, or 3TC), 3'-azido-2',3'-dideoxy-5-methyl-cytidine (5-Me-AZDC), and 3'-azido-2',3'-dideoxyuridine (AZDU) on Epstein-Barr virus (EBV) DNA replication in vitro were tested in P3HR-1 cells. Two anti-EBV drugs, 3'-azido-3'-deoxythymidine (AZT) and 9-(1,3-dihydroxy-2-propoxymethyl)guanine (DHPG, or ganciclovir), were used as positive controls. The inhibitory effects on EBV DNA synthesis were quantified by membrane filter and Southern blot hybridizations with an EBV-specific probe BamHI-W fragment. The 50% effective doses (ED50) for EBV DNA replication were 0.15, 0.83, 1.5, 8.3, 14, and 7.7 microM for DHPG, (-)-L-beta-DOC, (+)-D-beta-DOC, (+)-D-beta-OTC, (-)-L-beta-OTC, and AZT, respectively. In contrast, 5-Me-AZDC and AZDU were not effective at concentrations as high as 30 microM. These results indicated that both (-)-L-beta-DOC and (+)-D-beta-DOC were more potent than AZT, which has previously been shown to have anti-EBV activity. (-)-L-beta-DOC and (+)-D-beta-DOC have also been previously demonstrated to suppress the infectivity of human immunodeficiency virus type 1 (HIV-1). Thus, (-)-L-beta-DOC represents the first nucleoside analog with L-configuration exhibiting significant antiviral activities against both EBV and HIV.


Assuntos
Antivirais/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Nucleosídeos/farmacologia , Linhagem Celular , DNA Viral/análise , HIV-1/efeitos dos fármacos , Herpesvirus Humano 4/genética , Humanos , Relação Estrutura-Atividade
18.
J Med Virol ; 45(2): 183-91, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7775937

RESUMO

To assess the role of the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene in the development of Hodgkin's lymphoma (HL), the polymorphism of this gene in EBV isolates from different geographic locations was analyzed. A 497 bp fragment spanning LMP1 gene exons 1 and 2 was amplified by polymerase chain reaction (PCR), using a primer pair bracketing a Xhol restriction site. PCR products were subjected to Xhol digestion and to DNA sequencing analysis. Twenty-five HL biopsy specimens from the United States and five HL and four non-Hodgkin's lymphoma (NHL) biopsy specimens from Italy were examined. Eighty percent of LMP1-positive samples (12 of 15) from the United States maintained the Xhol restriction site and the remaining 20% partially lost the Xhol site. One of four EBV-positive HL and one of the three EBV-positive NHL specimens from Italy lost the restriction site. The other three EBV-positive HL DNAs were partially cut by Xhol. Direct DNA sequencing analysis revealed that those Italian samples not digested by Xhol were due to a G to C transversion at the first base of codon 18, resulting in the change of glycine to arginine. Those DNA samples partially cut by Xhol were due to a mixture of G/C at the same location. In contrast, those partially digested American HL DNAs had a mixture of G/T at the second base of codon 17.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Genes Virais , Variação Genética , Herpesvirus Humano 4/genética , Doença de Hodgkin/virologia , Proteínas da Matriz Viral/genética , Sequência de Bases , Primers do DNA/genética , DNA Viral/genética , Desoxirribonucleases de Sítio Específico do Tipo II , Genótipo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Itália , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Estados Unidos
19.
Leuk Lymphoma ; 15(5-6): 389-97, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7873996

RESUMO

Previous studies on the genotyping of Epstein-Barr virus (EBV) have been based on the analysis of a single gene locus. The assignment of genotype of an isolate could easily be over-looked with this assay. Our strategy for precision of EBV genotyping has exploited the existence of two families of EBV strains (type A and B) that can be distinguished at three divergent gene loci (EBNA-2, EBNA-3C, and EBER). To precisely determine the genotype of EBV in Hodgkin's disease (HD), we designed primers and simultaneously analysed these three gene loci that distinguish type A and B viruses by the polymerase chain reaction (PCR) technique. The primers designed to amplify these three gene loci encompass either type-specific deletion sequences (EBNA-2 and EBNA-3C) or type-specific point mutations (EBER) that identify the virus strain based on the sizes of PCR-amplified products or the mobility shifts in single-strand conformation polymorphism (SSCP) analysis. The locations of point mutations were identified by direct sequencing of the PCR-amplified DNA. Fifteen EBV-infected cell lines were analysed and a good correlation between EBNA-2 and EBNA-3C typing results was found. In contrast, approximately 33% of the cell lines analysed maintained type A sequences in EBNA-2 and EBNA-3C genes while carrying type B sequences in the EBER region. Data obtained from analysis of cell lines served as a reference for studying HD samples. EBV DNA was detected in about 70% of HD. Among the EBV-positive samples, 56% were associated with type A virus, 13% with type B, and 31% with dual viral sequences.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Genes Virais , Herpesvirus Humano 4/classificação , Doença de Hodgkin/virologia , Antígenos Virais/genética , Sequência de Bases , Proteínas de Ligação a DNA/genética , Antígenos Nucleares do Vírus Epstein-Barr , Genótipo , Humanos , Dados de Sequência Molecular , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Deleção de Sequência , Células Tumorais Cultivadas
20.
Virus Genes ; 8(3): 231-41, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7975269

RESUMO

The DNA polymerase gene of Epstein-Barr virus (EBV) was cloned into baculovirus transfer vector (pBlueBac). The recombinant baculovirus (AcEBP-15) was obtained by cotransfection of Spodoptera frugiperda (Sf9) cells with infectious DNA from Autographa californica multiple nuclear polyhedrin virus (AcMNPV) and pBlueBac plasmid carrying EBV polymerase gene. Infection of Sf9 cells with the recombinant virus produced substantial quantities of the EBV DNA polymerase protein of the expected size (110 kD). The identity of the EBV polymerase 110-kD polypeptide was determined by (a) immunoprecipitation and Western blot analyses with rabbit polyclonal antiserum specific for a synthetic peptide derived from the coding sequence of the polymerase gene; (b) identification of a polypeptide of identical size (110 kD) from EBV-infected cells; (c) measurement of DNA polymerase activity similar to that of the enzyme induced in EBV-infected cells; and (d) neutralization of the enzymatic activity by the rabbit antiserum and inhibition by phosphonoacetic acid. Our results indicate that the baculovirus expression system provides large quantities of functional polymerase suitable for biochemical and structural analyses, thereby furthering our understanding of the mechanism of viral DNA replication and its inhibition by antiviral drugs.


Assuntos
Proteínas de Ligação a DNA , DNA Polimerase Dirigida por DNA/biossíntese , Genes pol/genética , Herpesvirus Humano 4/enzimologia , Proteínas Virais , Proteínas Estruturais Virais/biossíntese , Replicação Viral/genética , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Sequência de Bases , Western Blotting , Células Cultivadas , Cromatografia DEAE-Celulose , Clonagem Molecular/métodos , DNA Polimerase Dirigida por DNA/genética , Regulação Enzimológica da Expressão Gênica , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/genética , Dados de Sequência Molecular , Testes de Precipitina , Proteínas Recombinantes de Fusão/biossíntese , Solubilidade , Spodoptera/virologia , Transfecção , Proteínas Estruturais Virais/genética
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