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1.
J Neurovirol ; 22(4): 472-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26733457

RESUMO

Infrastructure for conducting neurological research in resource-limited settings (RLS) is limited. The lack of neurological and neuropsychological (NP) assessment and normative data needed for clinical interpretation impedes research and clinical care. Here, we report on ACTG 5271, which provided neurological training of clinical site personnel and collected neurocognitive normative comparison data in diverse settings. At ten sites in seven RLS countries, we provided training for NP assessments. We collected normative comparison data on HIV- participants from Brazil (n = 240), India (n = 480), Malawi (n = 481), Peru (n = 239), South Africa (480), Thailand (n = 240), and Zimbabwe (n = 240). Participants had a negative HIV test within 30 days before standardized NP exams were administered at baseline and 770 at 6 months. Participants were enrolled in eight strata, gender (female and male), education (<10 and ≥10 years), and age (<35 and ≥35 years). Of 2400 enrolled, 770 completed the 6-month follow-up. As expected, significant between-country differences were evident in all the neurocognitive test scores (p < 0.0001). There was variation between the age, gender, and education strata on the neurocognitive tests. Age and education were important variables for all tests; older participants had poorer performance, and those with higher education had better performance. Women had better performance on verbal learning/memory and speed of processing tests, while men performed better on motor tests. This study provides the necessary neurocognitive normative data needed to build infrastructure for future neurological and neurocognitive studies in diverse RLS. These normative data are a much-needed resource for both clinicians and researchers.


Assuntos
Ensaios Clínicos como Assunto , Cognição/fisiologia , Pessoal de Saúde/educação , Testes de Estado Mental e Demência , Adulto , África , Fatores Etários , Ásia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/psicologia , Países em Desenvolvimento/economia , Escolaridade , Feminino , Infecções por HIV/complicações , Infecções por HIV/psicologia , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , América do Sul , Aprendizagem Verbal/fisiologia
2.
J Neurovirol ; 20(3): 294-303, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696364

RESUMO

The reasons for persistent brain dysfunction in chronically HIV-infected persons on stable combined antiretroviral therapies (CART) remain unclear. Host and viral factors along with their interactions were examined in 260 HIV-infected subjects who underwent magnetic resonance spectroscopy (MRS). Metabolite concentrations (NAA/Cr, Cho/Cr, MI/Cr, and Glx/Cr) were measured in the basal ganglia, the frontal white matter, and gray matter, and the best predictive models were selected using a bootstrap-enhanced Akaike information criterion (AIC). Depending on the metabolite and brain region, age, race, HIV RNA concentration, ADC stage, duration of HIV infection, nadir CD4, and/or their interactions were predictive of metabolite concentrations, particularly the basal ganglia NAA/Cr and the mid-frontal NAA/Cr and Glx/Cr, whereas current CD4 and the CPE index rarely or did not predict these changes. These results show for the first time that host and viral factors related to both current and past HIV status contribute to persisting cerebral metabolite abnormalities and provide a framework for further understanding neurological injury in the setting of chronic and stable disease.


Assuntos
Complexo AIDS Demência , Antirretrovirais/uso terapêutico , Espectroscopia de Ressonância Magnética/métodos , Complexo AIDS Demência/tratamento farmacológico , Complexo AIDS Demência/metabolismo , Complexo AIDS Demência/patologia , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Gânglios da Base/metabolismo , Gânglios da Base/patologia , Gânglios da Base/virologia , Colina/metabolismo , Doença Crônica , Creatina/metabolismo , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Lobo Frontal/virologia , Substância Cinzenta/metabolismo , Substância Cinzenta/patologia , Substância Cinzenta/virologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prótons , Substância Branca/metabolismo , Substância Branca/patologia , Substância Branca/virologia
3.
HIV Clin Trials ; 15(6): 246-60, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25433664

RESUMO

BACKGROUND: Convenient dosing, potency, and low toxicity support use of tenofovir disoproxil fumarate (TDF) as preferred nucleotide reverse transcriptase inhibitor (NRTI) for HIV-1 treatment. However, renal and metabolic safety of TDF compared to other NRTIs has not been well described in resource-limited settings. METHODS: This was a secondary analysis examining the occurrence of renal abnormalities (RAs) and renal and metabolic serious non-AIDS-defining events (SNADEs) through study follow-up between participants randomized to zidovudine (ZDV)/lamivudine/ efavirenz and TDF/emtricitabine/efavirenz treatment arms within A5175/PEARLS trial. Exact logistic regression explored associations between baseline covariates and RAs. Response profile longitudinal analysis compared creatinine clearance (CrCl) over time between NRTI groups. RESULTS: Twenty-one of 1,045 participants developed RAs through 192 weeks follow-up; there were 15 out of 21 in the TDF arm (P = .08). Age 41 years or older (odds ratio [OR], 3.35; 95% CI, 1.1-13.1), his- tory of diabetes (OR, 10.7; 95% CI, 2.1-55), and lower baseline CrCl (OR, 3.1 per 25 mL/min decline; 95% CI, 1.7-5.8) were associated with development of RAs. Renal SNADEs occurred in 42 participants; 33 were urinary tract infections and 4 were renal failure/insufficiency; one event was attributed to TDF. Significantly lower CrCl values were maintained among patients receiving TDF compared to ZDV (repeated measures analysis, P = .05), however worsening CrCl from baseline was not observed with TDF exposure over time. Metabolic SNADEs were rare, but were higher in the ZDV arm (20 vs 3; P < .001). CONCLUSIONS: TDF is associated with lower serious metabolic toxicities but not higher risk of RAs, serious renal events, or worsening CrCl over time compared to ZDV in this randomized multinational study.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Nefropatias/induzido quimicamente , Doenças Metabólicas/induzido quimicamente , Adulto , Fármacos Anti-HIV/administração & dosagem , Quimioterapia Combinada , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
4.
Clin Infect Dis ; 55(6): 868-76, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22661489

RESUMO

BACKGROUND: AIDS Clinical Trials Group (ACTG) A5199 compared the neurological and neuropsychological (NP) effects of 3 antiretroviral regimens in participants infected with human immunodeficiency virus type 1 (HIV-1) in resource-limited settings. METHODS: Participants from Brazil, India, Malawi, Peru, South Africa, Thailand, and Zimbabwe were randomized to 3 antiretroviral treatment arms: A (lamivudine-zidovudine plus efavirenz, n = 289), B (atazanavir, emtricitabine, and didanosine-EC, n = 293), and C (emtricitabine-tenofovir-disoproxil fumarate plus efavirenz, n = 278) as part of the ACTG PEARLS study (A5175). Standardized neurological and neuropsychological (NP) screening examinations (grooved pegboard, timed gait, semantic verbal fluency, and finger tapping) were administered every 24 weeks from February 2006 to May 2010. Associations with neurological and neuropsychological function were estimated from linear and logistic regression models using generalized estimating equations. RESULTS: The median weeks on study was 168 (Q1 = 96, Q3 = 192) for the 860 participants. NP test scores improved (P < .05) with the exception of semantic verbal fluency. No differences in neurological and neuropsychological functioning between treatment regimens were detected (P > .10). Significant country effects were noted on all NP tests and neurological outcomes (P < .01). CONCLUSIONS: The study detected no significant differences in neuropsychological and neurological outcomes between randomized ART regimens. Significant improvement occurred in neurocognitive and neurological functioning over time after initiation of ARTs. The etiology of these improvements is likely multifactorial, reflecting reduced central nervous system HIV infection, better general health, and practice effects. This study suggests that treatment with either of the World Health Organization -recommended first-line antiretroviral regimens in resource-limited settings will improve neuropsychological functioning and reduce neurological dysfunction. CLINICAL TRIALS REGISTRATION: NCT00096824.


Assuntos
Complexo AIDS Demência/epidemiologia , Complexo AIDS Demência/prevenção & controle , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Feminino , HIV-1/patogenicidade , Humanos , Masculino , Exame Neurológico , Testes Psicológicos , Resultado do Tratamento
5.
HIV Med ; 13(7): 427-35, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22413938

RESUMO

OBJECTIVES: The aim of the study was to investigate the frequency and severity of adverse events (AEs) and laboratory abnormalities of interest over 96 weeks of treatment with etravirine or placebo in the pooled TMC125 DUET (Demonstrate Undetectable viral load in patients Experienced with ARV Therapy) trials. METHODS: Treatment-experienced, HIV-1-infected patients randomly received etravirine 200 mg twice a day (bid) or placebo, plus a background regimen. The frequency and severity of neuropsychiatric, rash, hepatic and lipid AEs were analysed; frequencies were also adjusted for total patient-years of exposure (PYE). RESULTS: A total of 599 and 604 patients received etravirine and placebo, respectively (median treatment duration 96.0 and 69.6 weeks, respectively). There was no significant difference between the treatment groups in the frequency of neuropsychiatric AEs. However, a significant difference in the frequency of rash was observed (20.5% vs. 11.8%, respectively; P < 0.0001); rash was generally mild to moderate in severity; the rate of discontinuation because of rash was low (2.2% vs. 0% in the etravirine and placebo groups, respectively). The frequency of hepatic AEs was low and similar between the treatment groups (8.7% vs. 7.1%, respectively; P = 0.3370); hepatic enzyme levels did not increase over time. Lipid-related laboratory abnormalities and changes over time in lipid levels were generally comparable between treatment groups. Adjusting for treatment exposure, the frequency of AEs remained similar between treatment groups, with the exception of rash [13.7 vs. 9.3 per 100 PYE; relative risk (95% confidence interval) 1.48 (1.02-1.95)]. CONCLUSIONS: The frequency of AEs of interest was generally similar between the treatment groups, both overall and when adjusted for treatment exposure, with the exception of rash which was more frequent in the etravirine group.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Fármacos Anti-HIV/efeitos adversos , Exantema/induzido quimicamente , Piridazinas/efeitos adversos , Adulto , Fármacos Anti-HIV/administração & dosagem , Tontura/induzido quimicamente , Método Duplo-Cego , Feminino , Cefaleia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/induzido quimicamente , Nitrilas , Piridazinas/administração & dosagem , Pirimidinas , Transtornos do Sono-Vigília/induzido quimicamente , Carga Viral
6.
J Med Case Rep ; 15(1): 90, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608053

RESUMO

BACKGROUND: Very little is known about the risk that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral infection poses to cancer patients, many of whom are immune compromised causing them to be more susceptible to a host of infections. As a precautionary measure, many clinical studies halted enrollment during the initial surge of the global Novel Coronavirus Disease (COVID-19) pandemic. In this case report, we detail the successful treatment of a relapsed and refractory multiple myeloma (MM) patient treated with an anti-B cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T cell therapy immediately following clinical recovery from COVID-19. CASE PRESENTATION: The 57 year old Caucasian male patient had a 4-year history of MM and was considered penta-refractory upon presentation for CAR T cell therapy. He had a history of immunosuppression and received one dose of lymphodepleting chemotherapy (LDC) the day prior to COVID-19 diagnosis; this patient was able to mount a substantial immune response against the SARS-CoV-2 virus, and antiviral antibodies remain detectable 2 months after receiving anti-BCMA CAR T cell therapy. The recent SARS-CoV-2 infection in this patient did not exacerbate CAR T-associated cytokine release syndrome (CRS) and conversely the CAR T cell therapy did not result in COVID-19-related complications. One month after CAR T cell infusion, the patient was assessed to have an unconfirmed partial response per International Myeloma Working Group (IMWG) criteria. CONCLUSION: Our case adds important context around treatment choice for MM patients in the era of COVID-19 and whether CAR T therapy can be administered to patients who have recovered from COVID-19. As the COVID-19 global pandemic continues, the decision of whether to proceed with CAR T cell therapy will require extensive discussion weighing the potential risks and benefits of therapy. This case suggests that it is possible to successfully complete anti-BCMA CAR T cell therapy after recovery from COVID-19. CRB-402 study registered 6 September 2017 at clinicaltrials.gov (NCT03274219).


Assuntos
Antígeno de Maturação de Linfócitos B/imunologia , COVID-19/fisiopatologia , Imunoterapia Adotiva/métodos , Mieloma Múltiplo/terapia , Receptores de Antígenos Quiméricos/imunologia , Anticorpos Antivirais/imunologia , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/imunologia , Teste de Ácido Nucleico para COVID-19 , Teste Sorológico para COVID-19 , Tosse , Ciclofosfamida/uso terapêutico , Progressão da Doença , Febre , Hospitalização , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , SARS-CoV-2 , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico
7.
AIDS ; 14(14): 2109-16, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-11061651

RESUMO

OBJECTIVE: To determine the relationship between human herpesvirus 8 (HHV-8 or Kaposi's sarcoma-associated herpesvirus) peripheral blood virus load and Kaposi's sarcoma (KS) clinical stage. DESIGN: Blinded, cross-sectional analysis of peripheral blood HHV-8 DNA levels in persons with AIDS-related KS in Harare, Zimbabwe. METHODS: Subjects were stratified by KS clinical stage. The amount of HHV-8 DNA in plasma and peripheral blood mononuclear cells (PBMC) was determined by quantitative real-time PCR amplification of the HHV-8 open reading frame 26. RESULTS: Thirty-one HIV-1/HHV-8-coinfected persons were studied: 26 subjects had histologically confirmed KS (one stage II, 11 stage III and 14 stage IV) and five subjects had antibodies to HHV-8 but did not have KS. The age, CD4 lymphocyte count and plasma HIV-1 RNA levels were similar in all groups. HHV-8 DNA was detected in the plasma of all HHV-8-infected subjects (range < 2.4 to 5.2 log10 copies/ml), but plasma HHV-8 DNA levels were not associated with KS disease stage. In contrast, the amount of HHV-8 DNA in PBMC (range < 0.7 to 4.5 log10 copies/microg) was strongly associated with KS clinical stage (P = 0.005). Among stage IV KS cases, there was a linear relationship between plasma and PBMC HHV-8 DNA levels (r2 = 0.42; P = 0.01). CONCLUSION: The strong association observed between the extent of KS disease and the levels of HHV-8 DNA in PBMC provides further evidence for a relationship between HHV-8 virus load and KS pathogenesis.


Assuntos
Infecções por HIV/virologia , HIV-1 , Herpesvirus Humano 8/isolamento & purificação , Sarcoma de Kaposi/virologia , Adulto , Estudos Transversais , DNA Viral/análise , Feminino , Infecções por HIV/complicações , Herpesvirus Humano 8/genética , Humanos , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Sarcoma de Kaposi/etiologia , Carga Viral , Replicação Viral , Zimbábue
10.
J Clin Microbiol ; 38(5): 1992-5, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10790138

RESUMO

A real-time PCR assay for quantitation of Kaposi's sarcoma-associated herpes virus (KSHV or human herpesvirus 8) DNA was evaluated. The linear dynamic range was 10 to 10(5) copies of KSHV DNA (r(2) > 0.99). The accuracy of DNA purification and quantitation was less than +/-0.4 log(10) copies for samples that contained from 10 to 10(5) copies of KSHV DNA. Cell-associated KSHV DNA was quantitated over a range of infected cell frequencies from 0. 1 to 10(-5), and cell-free KSHV DNA in plasma was quantitated over a range of 100 to 10(6) copies/ml. Real-time PCR provides a convenient method for quantitation of cell-free and cell-associated KSHV DNA in laboratory and clinical specimens.


Assuntos
Herpesvirus Humano 8/isolamento & purificação , Sarcoma de Kaposi/diagnóstico , Linhagem Celular , DNA Viral/sangue , Herpesvirus Humano 8/fisiologia , Humanos , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Sarcoma de Kaposi/sangue , Sensibilidade e Especificidade , Vírion/fisiologia , Replicação Viral
11.
RNA ; 1(6): 598-609, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7489519

RESUMO

Positions 2-6 of the substrate-binding internal guide sequence (IGS) of the L-21 Sca I form of the Tetrahymena thermophila intron were mutagenized to produce a GN5 IGS library. Ribozymes within the GN5 library capable of efficient cleavage of an 818-nt human immunodeficiency virus type 1 vif-vpr RNA, at 37 degrees C, were identified by ribozyme-catalyzed guanosine addition to the 3' cleavage product. Three ribozymes (IGS = GGGGCU, GGCUCC, and GUGGCU) within the GN5 library that actively cleaved the long substrate were characterized kinetically and compared to the wild-type ribozyme (GGAGGG) and two control ribozymes (GGAGUC and GGAGAU). The two control ribozymes have specific sites within the long substrate, but were not identified during screening of the library. Under single-turnover conditions, ribozymes GGGGCU, GGCUCC, and GUGGCU cleaved the 818-nt substrate 4- to 200-fold faster than control ribozymes. Short cognate substrates, which should be structureless and therefore accessible to ribozyme binding, were cleaved at similar rates by all ribozymes except GGGGCU, which showed a fourfold rate enhancement. The rate of cleavage of long relative to short substrate under single-turnover conditions suggests that GGCUCC and GUGGCU were identified because of accessibility to their specific cleavage sites within the long substrate (substrate-specific effects), whereas GGGGCU was identified because of an enhanced rate of substrate binding despite a less accessible site in the long substrate. Even though screening was performed with 100-fold excess substrate (relative to total ribozyme), the rate of multiple-turnover catalysis did not contribute to identification of trans-cleaving ribozymes in the GN5 library.


Assuntos
RNA Catalítico/metabolismo , RNA de Protozoário/metabolismo , RNA/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Primers do DNA , Dados de Sequência Molecular , Especificidade por Substrato , Tetrahymena
12.
Biochemistry ; 35(35): 11493-502, 1996 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-8784205

RESUMO

Binding of substrate by the ribozyme derived from the self-splicing intron of Tetrahymena thermophila involves at least two steps. In the first step, base pairing between the ribozyme internal guide sequence (IGS) and the substrate forms a helical duplex (P1). Through specific tertiary interactions between P1 and the ribozyme core, P1 is then docked into the ribozyme active site. We have investigated the effects of compensatory mutations in positions 2-6 of the P1 helix on docking of P1 into the ribozyme core. Equilibrium binding of matching oligonucleotides by catalytically active IGS mutant ribozymes was evaluated by gel-shift analysis. While the strength of base pairing changed with base composition as expected, the strength of tertiary interactions between P1 and the ribozyme core was not affected by the P1 mutations. These results support a model in which efficient docking of P1 is determined by P1 structure and the presence of a conserved G-U pair. Determination of the rate of dissociation of matching oligonucleotides from each ribozyme revealed that mutations in the IGS change the tightness of binding by increasing or decreasing the dissociation rate. Surprisingly, dissociation rates determined in this fashion were 20-900-fold less than the values of the multiple-turnover rate constant for these ribozymes, initially suggesting that turnover did not require product dissociation. A more detailed analysis for the wild-type ribozyme defined two distinct product dissociation rates. The slower rate equaled that determined under the conditions used for the equilibrium binding studies. The weighted average of the two dissociation rates equaled the multiple-turnover rate constant. These results are explained by a model in which ribozyme preparations consist of two ribozyme conformers: one with tight docking of P1 and another with weaker docking of P1.


Assuntos
Mutação , RNA Catalítico/genética , RNA Catalítico/metabolismo , Tetrahymena thermophila/genética , Animais , Composição de Bases , Sequência de Bases , Sítios de Ligação , Catálise , Cinética , Conformação de Ácido Nucleico , Oligorribonucleotídeos/síntese química , Oligorribonucleotídeos/metabolismo , Splicing de RNA , RNA Catalítico/química
13.
J Bacteriol ; 155(2): 806-16, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6603457

RESUMO

The relationship between the culture levels of guanosine-5'-diphosphate-3'-diphosphate (ppGpp) and the rates of synthesis and accumulation of cellular phospholipids was examined in cultures of Rhodopseudomonas sphaeroides that had been subjected to immediate decreases in incident light intensity. After a high-to-low light transition of high-light-adapted cells, an immediate inhibition of total cellular phospholipid production occurred coincident with a rapid accumulation of culture ppGpp. The inhibition of phospholipid accumulation occurred at the level of phospholipid synthesis rather than turnover, and both the extent of ppGpp accumulation and the degree of inhibition of phospholipid synthesis were directly dependent upon the magnitude of the light transition. Maximum inhibition (greater than 90%) of the rate of cellular phospholipid synthesis occurred after transitions from 5,350 to 268 1x and lower, including transitions to the dark, with comparable inhibition being exerted upon the rates of synthesis of individual species of phospholipids. Reinitiation of culture phospholipid accumulation in cultures shifted from 5,350 to 1,070 1x and lower occurred 65 to 70 min subsequent to the downshift in light intensity, apparently irrespective of the culture level of ppGpp.


Assuntos
Fosfolipídeos/biossíntese , Rhodobacter sphaeroides/metabolismo , Guanosina Tetrafosfato/análise , Luz , Nucleotídeos/análise
14.
J Bacteriol ; 153(2): 782-90, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6600450

RESUMO

Exogenously supplied long-chain fatty acids have been shown to markedly alleviate the inhibition of phototrophic growth of cultures of Rhodopseudomonas sphaeroides caused by the antibiotic cerulenin. Monounsaturated and polyunsaturated C18 fatty acids were most effective in relieving growth inhibition mediated by cerulenin. Medium supplementation with saturated fatty acids (C14 to C18) failed to influence the inhibitory effect of cerulenin. The addition of mixtures of unsaturated and saturated fatty acids to the growth medium did not enhance the growth of cerulenin-inhibited cultures above that obtained with individual unsaturated fatty acids as supplements. Resolution and fatty acid analysis of the extractable lipids of R. sphaeroides revealed that exogenously supplied fatty acids were directly incorporated into cellular phospholipids. Cells treated with cerulenin displayed an enrichment in their percentage of total saturated fatty acids irrespective of the presence of exogenous fatty acids. Cerulenin produced comparable inhibitions of the rates of both fatty acid and phospholipid synthesis and was further found to preferentially inhibit unsaturated fatty acid synthesis.


Assuntos
Ácidos Graxos/metabolismo , Rhodobacter sphaeroides/metabolismo , Cerulenina/farmacologia , Ácidos Graxos/farmacologia , Ácidos Graxos Insaturados/metabolismo , Ácido Linoleico , Ácidos Linoleicos/farmacologia , Ácidos Linolênicos/farmacologia , Lipídeos de Membrana/metabolismo , Ácido Oleico , Ácidos Oleicos/farmacologia , Fosfolipídeos/metabolismo , Rhodobacter sphaeroides/efeitos dos fármacos
15.
Clin Infect Dis ; 14(4): 942-4, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1576290

RESUMO

Fungal prostatitis is an uncommon disease whose presentation is usually similar to that of benign prostatic hypertrophy and is usually diagnosed unexpectedly after surgery for relief of prostatic obstruction. To our knowledge, we report the first case of prostatic aspergillosis that developed as a complication of indwelling bladder catheterization. This unusual manifestation of invasive aspergillosis occurred in a patient at risk for invasive fungal disease because of chronic corticosteroid use and recent administration of broad-spectrum antibiotics. The previously reported cases of prostatic aspergillosis are reviewed.


Assuntos
Aspergilose/etiologia , Cateteres de Demora/efeitos adversos , Prostatite/etiologia , Cateterismo Urinário/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade
16.
Nucleic Acids Res ; 25(24): 4985-93, 1997 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9396806

RESUMO

Inhibition of gene expression by catalytic RNA (ribozymes) requires that ribozymes efficiently cleave specific sites within large target RNAs. However, the cleavage of long target RNAs by ribozymes is much less efficient than cleavage of short oligonucleotide substrates because of higher order structure in the long target RNA. To further study the effects of long target RNA structure on ribozyme cleavage efficiency, we determined the accessibility of seven hammerhead ribozyme cleavage sites in a target RNA that contained human immunodeficiency virus type 1 (HIV-1) vif - vpr . The base pairing-availability of individual nucleotides at each cleavage site was then assessed by chemical modification mapping. The ability of hammerhead ribozymes to cleave the long target RNA was most strongly correlated with the availability of nucleotides near the cleavage site for base pairing with the ribozyme. Moreover, the accessibility of the seven hammerhead ribozyme cleavage sites in the long target RNA varied by up to 400-fold but was directly determined by the availability of cleavage sites for base pairing with the ribozyme. It is therefore unlikely that steric interference affected hammerhead ribozyme cleavage. Chemical modification mapping of cleavage site structure may therefore provide a means to identify efficient hammerhead ribozyme cleavage sites in long target RNAs.


Assuntos
Conformação de Ácido Nucleico , RNA Catalítico/metabolismo , RNA Viral/metabolismo , Composição de Bases , Genes vif , Genes vpr , HIV-1/genética , Humanos , RNA Viral/química , Especificidade por Substrato
17.
J Bacteriol ; 146(2): 790-7, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7012139

RESUMO

An experimental procedure for rapidly obtaining cell populations of phototrophically growing Rhodopseudomonas sphaeroides which display division and genomic synchrony has been developed. The basis of the procedure resides with the normal physiological response displayed by cells of R. sphaeroides that have been subjected to an immediate decrease in incident light intensity. After an abrupt high- to low-light transition of an asynchronously dividing cell population, an immediate cessation of increases in culture turbidity, total cell number, and net accumulations of culture deoxyribonucleic acid and phospholipid occurs. Total cell number remains constant for 2.5 h after the transition to low light, after which time, it undergoes a sharp increase. Reinitiation of high-light conditions of growth 1 h subsequent to this increase in total cell number results in a cell population possessing a high degree of division and genomic synchrony. A characterization of this procedure, together with a demonstration of its utility for studies on intracytoplasmic membrane assembly, is presented.


Assuntos
Técnicas Bacteriológicas , Rhodobacter sphaeroides/citologia , Divisão Celular , DNA Bacteriano/biossíntese , Membranas Intracelulares/metabolismo , Luz , Fosfolipídeos/biossíntese , Rhodobacter sphaeroides/crescimento & desenvolvimento , Rhodobacter sphaeroides/metabolismo
18.
J Acquir Immune Defic Syndr ; 22(4): 333-40, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10634194

RESUMO

OBJECTIVE: To determine the prevalence of human herpesvirus 8 (HHV-8) infection in men treated for HIV-1 infection in Denver, Colorado. DESIGN: Cross-sectional analysis METHODS: Blood samples were obtained from 216 HIV-1-infected men. Antibody to latency-associated nuclear antigen (LANA) was detected by an immunofluorescent assay and the presence of HHV-8 in peripheral blood mononuclear cells (PBMC) was detected by polymerase chain reaction amplification. RESULTS: Among HIV-1-infected men who did not have Kaposi's sarcoma (KS), prevalence of HHV-8 infection was 46% (95% confidence interval [CI], 0.39-0.52). LANA seropositivity was common both among subjects with KS and subjects without KS (69% versus 42%; p = .06), but detection of HHV-8 DNA in peripheral blood was strongly associated with a diagnosis of KS (44% versus 10%; p = .001). In a univariate analysis of study subjects without KS, neither the odds of LANA seropositivity nor detection of HHV-8 DNA in PBMC was significant for CD4+ lymphocyte count, HIV-1 virus load, the use of three drug antiretroviral regimens or the prior occurrence of non-KS AIDS-related conditions. CONCLUSION: Although antibodies to HHV-8 are common among HIV-1-infected men, detection of HHV-8 DNA in PBMC is uncommon and is associated with a diagnosis of Kaposi's sarcoma.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções por HIV/tratamento farmacológico , HIV-1 , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/isolamento & purificação , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adulto , Fármacos Anti-HIV/uso terapêutico , Anticorpos Antivirais/sangue , Antígenos Virais , Estudos Transversais , DNA Viral/sangue , Imunofluorescência , Infecções por HIV/complicações , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/imunologia , Reação em Cadeia da Polimerase , Prevalência , Carga Viral
19.
J Infect Dis ; 168(2): 318-26, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7687641

RESUMO

The bisheteroarylpiperazine nonnucleoside reverse transcriptase (RT) inhibitor atevirdine effectively inhibits human immunodeficiency virus type 1 (HIV-1) in vitro. Clinical isolates with a wide range of 50% inhibitory concentrations (IC50s) of zidovudine (IC50, 0.003 to > 2.0 microM) and didanosine (IC50, 0.02 to > 10.0 microM) were inhibited by atevirdine (median IC50, 0.74 microM; range, 0.06-1.60). Cross-resistance to atevirdine in zidovudine- or didanosine-resistant isolates was not observed. Combinations of atevirdine and zidovudine were highly synergistic against zidovudine-resistant clinical isolates of HIV-1. By contrast, these combinations were mostly additive when tested against zidovudine-susceptible isolates. Combinations of atevirdine and didanosine were additive in their effects against both didanosine-susceptible and -resistant isolates. These data suggest that the interaction of atevirdine with HIV-1 RT is different than that of other nonnucleoside RT inhibitors and that combinations of atevirdine and zidovudine may be useful in patients with AIDS who have initially received monotherapy with zidovudine.


Assuntos
Antivirais/farmacologia , Didanosina/farmacologia , HIV-1/efeitos dos fármacos , Piperazinas/farmacologia , Zidovudina/farmacologia , Células Cultivadas , Infecções por HIV/microbiologia , Transcriptase Reversa do HIV , HIV-1/fisiologia , Humanos , Testes de Sensibilidade Microbiana , Inibidores da Transcriptase Reversa , Replicação Viral/efeitos dos fármacos
20.
J Infect Dis ; 178(5): 1488-91, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9780272

RESUMO

The prevalence of human herpesvirus 8 (HHV-8; Kaposi's sarcoma [KS] herpesvirus) infection was determined by IFA in 297 persons living in Brazil and Colorado. The prevalence of antibody to HHV-8 in human immunodeficiency virus (HIV) type 1-seropositive gay men with and without KS was similar in Brazil and Colorado. In Brazil, the prevalence of HHV-8 antibody was significantly greater in HIV-1-seronegative gay men than in HIV-1-seronegative male intravenous drug users. HHV-8-seropositive Brazilian gay men who had a clinical diagnosis of KS or who were infected with HIV-1 had significantly higher titers of HHV-8 antibody than did HHV-8-seropositive, HIV-1-seronegative Brazilian gay men. These findings provide further support for the association between HHV-8 infection and KS and suggest that, as in the United States, HHV-8 infection is transmitted sexually in Brazil.


Assuntos
Anticorpos Antivirais/análise , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/imunologia , Adolescente , Adulto , Brasil/epidemiologia , Linhagem Celular , Colorado/epidemiologia , Feminino , Infecções por HIV/virologia , Soronegatividade para HIV , HIV-1 , Homossexualidade Masculina , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Abuso de Substâncias por Via Intravenosa/epidemiologia
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