RESUMEN
To assess immunological parameters, including markers of immune activation, in highly HIV-1-exposed uninfected (EU) Vietnamese intravascular drug users (IDUs) in comparison with HIV-1-infected IDUs and HIVunexposed controls, we determined peripheral lymphocyte phenotypes in fresh whole blood samples from 32 EU IDUs, 28 HIV+ IDUs, and 26 blood donors. We found higher levels of activation markers (CD38, HLADR) on CD4+ and CD8+ T cells, lower percentages of naive CD4+ and CD8+ T cells, higher percentages of CD8+ T cells and of CD8+ T cells expressing CD25, and lower levels of CXCR4+CD4+ T cells in EU IDUs than in unexposed controls. Despite several differences in CD4+ and CD8+ T cell subset phenotypes, both EU and HIV+ IDUs exhibited a pattern of peripheral immune activation. Lymphocyte activation in EU IDUs may reflect immune stimulation driven by viral infections other than HIV-1 and/or allogeneic stimulation associated with needle sharing. Our results suggest that immune activation does not necessarily favor HIV-1 transmission, but, on the contrary, may alter the susceptibility of EUs to HIV-1 infection and contribute to their resistance.
Asunto(s)
Linfocitos B/inmunología , Seronegatividad para VIH/inmunología , VIH-1/fisiología , Células Asesinas Naturales/inmunología , Abuso de Sustancias por Vía Intravenosa , Subgrupos de Linfocitos T/inmunología , Adulto , Antígenos CD19/inmunología , Antígeno CD56/inmunología , Estudios de Casos y Controles , Susceptibilidad a Enfermedades , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunofenotipificación , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , Receptores de IgG/inmunología , Factores de Riesgo , Vietnam/epidemiologíaRESUMEN
OBJECTIVE: We and others have reported the presence of Chlamydia and other bacterial species in joint specimens from patients with reactive arthritis (ReA). The present study was conducted to investigate whether bacteria other than those specified by diagnostic criteria for ReA could be identified in synovial fluid (SF) or tissue from patients with various arthritides, and whether the presence of such organisms corresponds to particular clinical characteristics in any patient set or subset. METHODS: DNA in synovial biopsy samples and SF obtained from 237 patients with various arthritides, including ReA, rheumatoid arthritis, and undifferentiated oligoarthritis, was assayed by polymerase chain reaction (PCR) using "panbacterial" primers; we chose only samples known to be PCR negative for Chlamydia, Borrelia, and Mycoplasma species. PCR products were cloned, and cloned amplicons from each sample were sequenced; DNA sequences were compared against all others in GenBank for identification of bacterial species involved. RESULTS: Ten percent of patient samples were PCR positive in panbacterial screening assays. Bacterial species identified belonged to the genera Neisseria, Acinetobacter, Moraxella, Salmonella, Pseudomonas, and others. Thirty-five percent of PCR-positive patients showed the presence of DNA from more than a single bacterial species in synovium; overall, however, we could identify no clear relationship between specific single or multiple bacterial species in the synovium and any general clinical characteristics of any individual or group of patients. CONCLUSION: This analysis provides the first systematic attempt to relate bacterial nucleic acids in the synovium to clinical characteristics, joint findings, and outcomes. Many patients with arthritis have bacterial DNA in the joint, and, in some cases, DNA from more than a single species is present. However, except for 1 case of a control patient with staphylococcal septic arthritis, it is not clear from the present study whether the synovial presence of such organisms is related to disease pathogenesis or evolution in any or all cases.
Asunto(s)
Artritis Reumatoide/microbiología , ADN Bacteriano/aislamiento & purificación , Bacilos y Cocos Aerobios Gramnegativos/aislamiento & purificación , Membrana Sinovial/microbiología , Acinetobacter/genética , Acinetobacter/aislamiento & purificación , Adulto , Anciano , Artritis Psoriásica/microbiología , Artritis Reactiva/microbiología , Biopsia , Niño , Clonación Molecular , Femenino , Bacilos y Cocos Aerobios Gramnegativos/genética , Humanos , Masculino , Persona de Mediana Edad , Moraxella/genética , Moraxella/aislamiento & purificación , Neisseria/genética , Neisseria/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Prohibitinas , Pseudomonas/genética , Pseudomonas/aislamiento & purificación , Salmonella/genética , Salmonella/aislamiento & purificación , Membrana Sinovial/patologíaRESUMEN
To define the medical characteristics of intravascular drug users in Ho Chi Minh City, Vietnam, we examined 280 men, of whom 235 were infected with human immunodeficiency virus (HIV), being treated in a rehabilitation center. The patients used mainly opium, often in shooting galleries (50%). The prevalence of oral candidiasis (58%) and zoster infection (20%) was high in HIV-seropositive patients, whereas oral hairy leukoplasia and Kaposi's sarcoma were absent. The prevalence of acquired immunodeficiency syndrome was 24%. More than 80% of the patients had infections with hepatitis C virus, hepatitis B virus, cytomegalovirus, or human T cell lymphotropic virus type-1. The CD4+ cell counts correlated well with viral load. Only HIV-1 subtype E was detected in the 30 patients tested. A cohort study of HIV-infected subjects in this population seems feasible, and would permit introduction of anti-retroviral therapy The large number of HIV-seronegative subjects sharing the same at-risk practices as the HIV-infected subjects raises the possibility of natural protection in this population.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Infecciones por VIH/complicaciones , VIH-1/aislamiento & purificación , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos , Estudios Transversales , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Seronegatividad para VIH , VIH-1/clasificación , VIH-1/fisiología , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Prevalencia , ARN Viral/sangre , Vietnam/epidemiología , Carga ViralRESUMEN
Here, we examine the cis-elements and trans-factors affecting the expression of asparagine synthetase (AS) genes whose transcription is negatively regulated by light. The promoters for the AS1 and AS2 genes of pea were isolated, sequenced, and functionally dissected for their ability to confer regulated expression to the GUS reporter gene in transgenic tobacco. Histochemical analysis of transgenic plants demonstrated that the AS1 and AS2 promoters show identical patterns of cell-specific expression. The more highly active AS1 promoter was further demonstrated to confer negative light-regulation to the GUS gene in transgenic tobacco. Deletion analysis and gain-of-function experiments showed that 124 bp of the AS1 promoter was sufficient to confer light-activated repression to a heterologous promoter. Potential conserved transcription regulatory elements, Box B, Box C, and Box C' within this region were shown to bind to nuclear proteins by gel shift analysis. A light-specific DNA:protein interaction was detected with Box B. The nuclear factors that bind to Box C and C' elements of AS1 are competed by a putative repressor element 'RE1' defined previously in the oat phytochrome gene whose transcription is also repressed by light. The Box B and C/C'-Box/RE1-binding factors were found in nuclear extracts of tobacco, pea, and Arabidopsis and may therefore be universal factors involved in light-activated transcriptional repression.
Asunto(s)
Aspartatoamoníaco Ligasa/biosíntesis , Regulación de la Expresión Génica de las Plantas/fisiología , Pisum sativum/enzimología , Secuencias Reguladoras de Ácidos Nucleicos , Avena/genética , Secuencia de Bases , Oscuridad , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación Enzimológica de la Expresión Génica/efectos de la radiación , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Genes de Plantas/efectos de la radiación , Glucuronidasa/biosíntesis , Luz , Pisum sativum/efectos de la radiación , Fitocromo/biosíntesis , Fitocromo/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/biosíntesis , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Transcripción Genética/efectos de la radiaciónAsunto(s)
Amidas/metabolismo , Aminoácidos/biosíntesis , Arabidopsis/genética , Luz , Mutación , Fijación del NitrógenoRESUMEN
Discrete apolipoprotein E-containing lipoproteins can be identified when EDTA plasma is fractionated on columns of 4% agarose. The present study has demonstrated, by physical and metabolic criteria, that these apolipoprotein E-containing lipoprotein subclasses may be further isolated by immunoaffinity chromatography. Whole plasma was first bound to an anti-apolipoprotein E immunoadsorbent prior to gel filtration on 4% agarose. After elution from the affinity column and dialysis, the bound fraction was chromatographed on 4% agarose. Discrete subfractions of apolipoprotein E could be demonstrated within elution volumes similar to those observed in the original plasma. When whole plasma was first submitted to gel filtration and the apolipoprotein E-containing lipoproteins of either intermediate- or of high-density lipoprotein (HDL) size were subsequently bound to anti-apolipoprotein E columns, the bound eluted fractions maintained their size and physical properties as shown by electron microscopy and by rechromatography on columns of 4% agarose. The metabolic integrity of apolipoprotein E-containing very-low-density lipoproteins (VLDL) was examined by coinjection into a cynomolgus monkey of 125I-labeled apolipoprotein E-rich and 131I-labeled apolipoprotein E-deficient human VLDL which had been separated by immunoaffinity chromatography. The plasma specific activity time curves of the apolipoprotein B in VLDL, intermediate-density (IDL) and low-density (LDL) lipoproteins demonstrated rates of decay and precursor-product relationships similar to those obtained after injection of whole labeled VLDL, supporting the metabolic integrity of VLDL isolated by immunoaffinity chromatography.