RESUMO
Background: HIV-1-controllers maintain HIV-1 viremia at low levels (normally <2000 HIV-RNA copies/mL) without antiretroviral treatment. However, some HIV-1-controllers have evidence of immunologic progression with marked CD4+T-cell decline. We investigated host genetic factors associated with protection against CD4+T-cell loss in HIV-1-controllers. Methods: We analysed the association of interferon lambda 4 (IFNL4)-related polymorphisms and HLA-B haplotypes within Long Term Non-Progressor HIV-1-controllers ((LTNP-C), defined by maintaining CD4+T-cells counts >500 cells/mm3 for more than 7 years after HIV-1 diagnosis) versus non-LTNP-C, who developed CD4+T-cells counts <500 cells/mm3 Both a Spanish study cohort (n=140) and an international validation cohort (n=914) were examined. Additionally, in a subgroup of individuals HIV-1-specific T-cell responses and soluble cytokines were analysed RESULTS: HLA-B*57 was independently associated with the LTNP-C phenotype (OR=3.056 (1.029-9.069) p=0.044 and OR=1.924 (1.252-2.957) p=0.003) while IFNL4 genotypes represented independent factors for becoming non-LTNP-C (TT/TT, ss469415590, OR=0.401 (0.171-0.942) p=0.036 or A/A, rs12980275, OR=0.637 (0.434-0.934) p=0.021) in the Spanish and validation cohort, respectively, after adjusting for sex, age at HIV-1 diagnosis, IFNL4-related polymorphisms and different HLA-B haplotypes. LTNP-C showed lower plasma IP-10 (p=0.019) and higher IFN-γ (p=0.02) levels than the HIV-1-controllers with diminished CD4+T-cell numbers. Moreover, LTNP-C exhibited higher quantities of IL2+CD57- and IFN-γ+CD57- HIV-1-specific CD8+T-cells (p=0.002 and 0.041, respectively) than non-LTNP-C. Conclusions: We have defined genetic markers able to segregate stable HIV-1-controllers from those who experience CD4+T-cell decline. These findings allow for identification of HIV-1-controllers at risk for immunologic progression, and provide avenues for personalized therapeutic interventions and precision medicine for optimizing clinical care of these individuals.
Assuntos
Predisposição Genética para Doença/genética , Infecções por HIV/genética , Antígenos HLA-B/genética , Interleucinas/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Coortes , Progressão da Doença , Feminino , Predisposição Genética para Doença/epidemiologia , Infecções por HIV/epidemiologia , HIV-1 , Humanos , Masculino , Adulto JovemRESUMO
OBJECTIVES: The aim of the study was to investigate whether very low level viraemia (VLLV) (20-50 HIV-1 RNA copies/mL) was associated with increased risk of virological failure (VF) as compared with persistent full suppression (< 20 copies/mL). METHODS: From the VACH Cohort database, we selected those patients who started antiretroviral therapy (ART) after January 1997 and who achieved effective viral suppression [two consecutive viral loads (VLs) < 50 copies/mL] followed by full suppression (at least one VL <20 copies/mL). We carried out survival analyses to investigate whether the occurrence of VLLV rather than maintaining full suppression at < 20 copies/mL was associated with virological failure (two consecutive VLs > 200 copies/mL or one VL > 200 copies/mL followed by a change of ART regimen, administrative censoring or loss to follow-up), adjusted for nadir CD4 cell count, sex, age, ethnicity, transmission group, type of ART and time on effective suppression at < 50 copies/mL. RESULTS: Of 21 480 patients who started ART, 13 674 (63.7%) achieved effective suppression at < 50 copies/mL, of whom 4289 (31.4%) further achieved full suppression at < 20 copies/mL after May 2009. A total of 2623 patients (61.1%) remained fully suppressed thereafter, while 1666 had one or more episodes of VL detection > 20 copies/mL (excluding virological failure). A total of 824 patients had VLLV after suppression at < 20 copies/mL. VLLV was not associated with virological failure as compared with persistent full suppression [hazard ratio (HR) 0.67; 95% confidence interval (CI) 0.44-1.00], independently of the number of blips recorded (from one to 18). CONCLUSIONS: In our population of HIV-infected patients on ART who achieved viral suppression at < 20 copies/mL, the risk of virological failure was no different for patients who remained fully suppressed compared with those who experienced subsequent episodes of VLLV.
Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , Resposta Viral Sustentada , Carga Viral , Viremia , Adolescente , Adulto , Estudos de Coortes , Feminino , Infecções por HIV/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Risco , Medição de Risco , Falha de Tratamento , Adulto JovemRESUMO
OBJECTIVE: To assess the changes on the HIV protease gene in plasma and peripheral blood mononuclear cell (PBMC) compartments during viral replication episodes in patients on boosted-darunavir monotherapy (mtDRV/rtv). METHODS: A prospective study was carried out in which adult HIV-1-infected patients who started mtDRV/rtv after viral suppression for ≥ 6 months with no major darunavir-related resistance mutations were enrolled. Patients with two consecutive plasma HIV RNA measurements >200 HIV-1 RNA copies/mL were considered as having virological failure (VF), while patients with two consecutive plasma HIV RNA measurements >50 copies/mL without meeting the VF criteria were considered to have virological rebound (VR). HIV protease genotypic profiles from plasma and PBMCs were performed at baseline and at VF and VR episodes. RESULTS: One hundred and fifty patients were included in the study, with overall VF and VR rates of 14% (n=21) and 14.7% (n=22), respectively. No major darunavir resistance mutations were observed in the plasma or PBMC samples. Circulating and cell-associated viruses showed a wild-type protease gene sequence in 54% and 23% of patients, respectively while the remainder patients only harboured minor protease inhibitor-associated mutations. Full concordance between plasma RNA and PBMC DNA protease genotypes was found in 23% of the sequences. CONCLUSIONS: No darunavir-related mutations were found in patients with VF or VR, either in plasma or in PBMCs; thus, simplification to mtDRV/rtv does not comprise future antiretroviral treatment options.
Assuntos
Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Mutação de Sentido Incorreto , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Adulto , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Estudos de Coortes , Darunavir , Feminino , Infecções por HIV/virologia , Protease de HIV , HIV-1/efeitos dos fármacos , Humanos , Masculino , Estudos Prospectivos , Ritonavir/administração & dosagem , Ritonavir/farmacologia , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genéticaRESUMO
While hepatitis C virus (HCV) infection seems to be expanding among HIV-infected men who have sex with men (MSM), the rate of coinfection in intravenous drug users (IDU) is assumed to remain constant. We evaluated the serial prevalence of HIV/HCV coinfection across all risk groups for HIV infection in Spain. We used data from 7045 subjects included in the multicentre, prospective Spanish Cohort of Adult HIV-infected Patients (CoRIS) between 2004 and 2011. We analysed risk factors for HIV/HCV coinfection by logistic regression analyses. The prevalence of HIV/HCV coinfection decreased from 25.3% (95% CI, 23.1-27.5) in 2004-2005 to 8.2% (95% CI, 6.9-9.5) in 2010-2011. This trend was consistently observed from 2004 to 2011 among all risk groups: IDU, 92.4% to 81.4%; MSM, 4.7% to 2.6%; heterosexual men, 13.0-8.9%; and heterosexual women, 14.5-4.0% (all P < 0.05). Strongest risk factors for HIV/HCV coinfection were IDU (OR, 54.9; 95% CI, 39.4-76.4), birth decade 1961-1970 (OR, 2.1; 95% CI, 1.1-3.7) and low educational level (OR, 2.4; 95% CI, 1.6-3.5). Hence, the prevalence of HIV/HCV coinfection decreased in Spain between 2004 and 2011. This decline was observed across all risk groups and is likely to be explained by a declining burden of HCV in the general population.
Assuntos
Coinfecção/epidemiologia , Infecções por HIV/complicações , Hepatite C/epidemiologia , Adulto , Animais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Espanha/epidemiologiaRESUMO
OBJECTIVES: To present clinical experience with a regimen including abacavir/lamivudineâ+âdarunavir/ritonavir in a cohort of HIV-1-infected patients. METHODS: A retrospective, multicentre cohort study, including all consecutive adult HIV-1-infected patients who started abacavir/lamivudineâ+âdarunavir/ritonavir from April 2008 to December 2010 and had at least one follow-up visit. The primary endpoint was HIV-1 viral load (VL) <40 copies/mL at week 48. RESULTS: One hundred and eighty-three patients (42 naive and 141 experienced) from 19 hospitals in Spain were studied. The median follow-up was 26.7 (0.5-58.6) months, 79.8% were men, the median age was 47.1 (21.4-80.5) years, 26.2% had AIDS and 38.8% were positive for hepatitis C virus. At baseline, the median CD4 count was 246 cells/mm(3) in naive patients and 393 cells/mm(3) in experienced patients and the median VL was 4.80 and <1.59 log copies/mL, respectively. At week 48, 81.8% of naive patients and 84.2% of experienced patients receiving the regimen reached a VL <40 copies/mL, whereas at 96 weeks this occurred in 90.5% and 92.8%, respectively. CD4 cell count increases at 48 and 96 weeks were +176.5 and +283.5 cells/mm(3) in naive patients and +74.9 and +93 cells/mm(3) in experienced patients, respectively. Overall, 86 (47%) patients discontinued the study regimen, in many cases possibly related to non-medical reasons, such as drug switches to reduce cost or changes in address due to economic constraints. Three patients died of causes unrelated to therapy and 19 (10.4%) discontinued the regimen due to adverse events. CONCLUSIONS: In our cohort, abacavir/lamivudineâ+âdarunavir/ritonavir was safe, well tolerated and achieved high rates of virological suppression. In a proportion of patients, discontinuation of this effective regimen was possibly due to non-medical reasons.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Didesoxinucleosídeos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Lamivudina/uso terapêutico , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fármacos Anti-HIV/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Estudos de Coortes , Darunavir , Didesoxinucleosídeos/efeitos adversos , Combinação de Medicamentos , Feminino , HIV-1/isolamento & purificação , Humanos , Lamivudina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ritonavir/efeitos adversos , Espanha , Sulfonamidas/efeitos adversos , Resultado do Tratamento , Carga Viral , Adulto JovemRESUMO
OBJECTIVES: The aim of the study was to assess the adequacy of initial antiretroviral therapy (ART), in terms of its timing and the choice of regimens, according to the Spanish national treatment guidelines [Spanish AIDS Study Group-National Plan for AIDS (GeSIDA-PNS) Guidelines] for treatment-naïve HIV-infected patients. METHODS: A prospective cohort study of HIV-positive ART-naïve subjects attending 27 centres in Spain from 2004 to 2010 was carried out. Regimens were classified as recommended, alternative or nonrecommended according to the guidelines. Delayed start of treatment was defined as starting treatment later than 12 months after the patient had fulfilled the treatment criteria. Multivariate logistic and Cox regression analyses were performed. RESULTS: A total of 6225 ART-naïve patients were included in the study. Of 4516 patients who started treatment, 91.5% started with a recommended or alternative treatment. The use of a nonrecommended treatment was associated with a CD4 count > 500 cells/µL [odds ratio (OR) 2.03; 95% confidence interval (CI) 1.14-3.59], hepatitis B (OR 2.23; 95% CI 1.50-3.33), treatment in a hospital with < 500 beds, and starting treatment in the years 2004-2006. Fourteen per cent of the patients had a delayed initiation of treatment. Delayed initiation of treatment was more likely in injecting drug users, patients with hepatitis C, patients with higher CD4 counts and during the years 2004-2006, and it was less likely in patients with viral loads > 5 log HIV-1 RNA copies/ml. The use of a nonrecommended regimen was significantly associated with mortality [hazard ratio (HR) 1.61; 95% CI 1.03-2.52; P = 0.035] and lack of virological response. CONCLUSIONS: Compliance with the recommendations of Spanish national guidelines was high with respect to the timing and choice of initial ART. The use of nonrecommended regimens was associated with a lack of virological response and higher mortality.
Assuntos
Terapia Antirretroviral de Alta Atividade , Fidelidade a Diretrizes/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Guias de Prática Clínica como Assunto , Adolescente , Adulto , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/análise , Análise de Regressão , Espanha , Resultado do Tratamento , Carga Viral , Adulto JovemRESUMO
Studies on the association between the peginterferon-α and ribavirin levels and sustained virological response (SVR) have shown yielded conflicting results, but most of them were performed before the influence of IL28B polymorphisms was known. Our aim was to assess the effects of peginterferon-α 2a and ribavirin plasma levels on viral kinetics and SVR in hepatitis C virus genotype 1 HCV-1/HIV-co-infected patients according to IL28B genotype. This was a cohort study of HCV-1/HIV-co-infected patients who were HCV-treatment naïve and for whom the efficacy of peginterferon-α 2a plus ribavirin was evaluated by per-protocol analysis. The peginterferon-α 2a and ribavirin levels were measured by ELISA and HPLC-UV, respectively. The relationships among host and viral factors, the trough drugs levels and virological responses were analysed by multivariate regression analyses. A total of 131 Caucasian patients were included (cirrhosis:38.9%). Overall, SVR rate was 39.6%. In patients with CC IL28B genotype, SVR was related neither to peginterferon-α 2a nor to ribavirin plasma levels, while higher levels of both drugs were the only variables independently associated with SVR in individuals with CT/TT IL28B genotypes (OR, 5.02; CI95 , 1.45-17.1; P = 0.001 and 4.0; CI95 , 1.08-14.7; P = 0.038, respectively). Moreover, faster viral declines were observed in CT/TT patients when pegIFN-α 2a and ribavirin plasma levels were greater than 3400 pg/mL and 1.6 µg/mL, respectively. In contrast to the results for CC patients, the results in patients carrying the unfavourable CT/TT IL28B genotypes showed that plasma levels of both drugs have significant effects on viral kinetics and SVR.
Assuntos
Genótipo , Infecções por HIV/genética , HIV-1/genética , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferon-alfa/uso terapêutico , Interleucinas/genética , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Terapia Antirretroviral de Alta Atividade , Antivirais/farmacocinética , Antivirais/uso terapêutico , Contagem de Linfócito CD4 , Coinfecção , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/efeitos adversos , Interferon-alfa/farmacocinética , Interferons , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/farmacocinética , Polimorfismo de Nucleotídeo Único , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Ribavirina/efeitos adversos , Ribavirina/farmacocinética , Fatores de Risco , Resultado do Tratamento , Carga Viral , Adulto JovemRESUMO
HIV elite controllers (EC) are a rare group of HIV-infected patients who are able to maintain undetectable viral loads during a long period of time in the absence of antiretroviral treatment. Adaptive immunity and host genetic factors, although implicated, do not entirely explain this phenomenon. On the other hand, plasmacytoid dendritic cells (pDCs) are the principal type I interferon (IFN) producers in response to viral infection, and it is unknown whether pDCs are involved in the control of HIV infection in EC. In our study, we analyzed peripheral pDC levels and IFN-α production by peripheral blood mononuclear cells (PBMCs) in EC compared to other groups of HIV-infected patients, the ability of pDCs to reduce HIV production in vitro, and the mechanisms potentially involved. We showed preserved pDC counts and IFN-α production in EC. We also observed a higher capacity of pDCs from EC to reduce HIV production and to induce T cell apoptosis, whereas pDCs from viremic patients barely responded without previous Toll-like receptor 9 (TLR-9) stimulus. The preserved functionality of pDCs from EC to reduce viral production may be one of the mechanisms involved in the control of HIV viremia in these subjects. These results demonstrate the importance of innate immunity in HIV pathogenesis, and an understanding of pDC mechanisms would be helpful for the design of new therapies.
Assuntos
Células Dendríticas/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV/imunologia , Adulto , Apoptose/imunologia , Antígenos CD4/metabolismo , Contagem de Linfócito CD4 , Linhagem Celular , Células Dendríticas/metabolismo , Feminino , Humanos , Interferon gama/biossíntese , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Carga ViralRESUMO
Whether HIV controllers, patients who spontaneously control HIV viraemia, are able to control hepatitis C virus (HCV) infection, in terms of spontaneous clearance or lower HCV replication, is not well understood. To assess to what extent Caucasian HIV controllers are able to control HCV replication and potential associated factors, plasma HIV-1 and HCV RNA levels, anti-HCV antibodies, HCV genotype and human leucocyte antigens (HLA) typing were determined in samples from 75 HIV controllers (33 viraemic controllers, <1000 HIV-1 RNA copies/mL, and 42 elite controllers, <40 HIV-1 RNA copies/mL) and compared with 261 HIV-infected noncontrollers. We did not find differences in the HCV spontaneous clearance rates between groups. However, we interestingly found a lower HCV viral load in HIV controllers, alongside a different distribution of HCV genotypes in relation to the comparison group. In addition, HLA-B57 was associated with a lower HCV viral load in the control group and HIV controllers, and conversely, HLA-B35 with higher HCV viral load in HIV controllers. The subrepresentation of HCV genotype 1 and the overrepresentation of HLA-B57 only partly explained the lower HCV viral load found in HIV controllers. In fact, HIV controller status was independently associated with lower HCV viral load, together with HCV genotype non-1, the presence of HLA-B57 and absence of HLA-B35. Caucasian HIV controllers are able to better control HCV replication, in terms of lower HCV viral load levels. These findings support the idea that some common host mechanisms are involved in the defence against these two persistent infections.
Assuntos
Coinfecção/virologia , Infecções por HIV/complicações , Hepacivirus/fisiologia , Hepatite C/virologia , Replicação Viral , Adulto , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Antígenos HLA-B/imunologia , Antígeno HLA-B35/imunologia , Hepatite C/complicações , Hepatite C/imunologia , Humanos , Imunidade Inata , Masculino , Pessoa de Meia-Idade , RNA Viral/biossíntese , RNA Viral/sangue , RNA Viral/imunologia , Carga Viral , Viremia/imunologia , Viremia/virologia , População BrancaRESUMO
BACKGROUND: Reports have shown that the publication of practice guidelines does not guarantee their use in clinical practice. The objective of this study was to evaluate the agreement between antiretroviral treatments (ARTs) prescribed in clinical practice and the recommendations in published guidelines. METHODS: A retrospective cohort study was carried out in ART-naïve adults of the Spanish Asociacion Medica Vach de Estudios Multicentricos (VACH) Cohort for the period from 2003 to 2006. RESULTS: A total of 945 patients initiated ART. Of these patients, 12.3% had a CD4 cell count above 350 cells/microL. A 'nonrecommended' antiretroviral regimen was prescribed to 5.3, 5.1 and 7.8% of patients with CD4 counts <200, 200-350 and >350 cells/microL, respectively. Multivariate analyses demonstrated that only a higher viral load was associated with the selection of a combination treatment that was recommended by the guidelines. CONCLUSIONS: Most patients were prescribed initial treatments in agreement with the recommendations. Appropriate routine data collection in databases can be used to evaluate the level of antiretroviral guideline compliance. We propose that routine evaluations of the guidelines must be part of quality assessment to improve medical care.
Assuntos
Antirretrovirais/uso terapêutico , Fidelidade a Diretrizes/normas , Infecções por HIV/tratamento farmacológico , HIV-1 , Guias de Prática Clínica como Assunto/normas , Padrões de Prática Médica , Adulto , Idoso , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Espanha , Fatores de Tempo , Carga ViralRESUMO
The mechanisms underlying downregulation of the cadherin/catenin complexes and beta-catenin signaling during tumor progression are not fully understood. We have analyzed the effect of oncogenic H-Ras on E-cadherin/catenin complex formation/stabilization and beta-catenin distribution in epidermal keratinocytes. Microinjection or stable expression of V12Ras into keratinocytes promotes the loss of E-cadherin and alpha-catenin and relocalization of beta-catenin to the cytoplasm and nucleus. Moreover, these effects are dependent on PI3K (phosphoinositide 3-OH kinase) activity. Interestingly, a strong association of p85alpha and p110alpha subunits of PI3K with beta-catenin is induced in V12Ras-expressing keratinocytes, and in vitro binding assays show a direct interaction between beta-catenin and p85alpha. Overexpression of either V12Ras or constitutively active p110alpha induces metabolic stabilization of beta-catenin and promotes its accumulation in cytoplasmic and nuclear pools. In addition, the interaction of beta-catenin with the adenomatous polyposis coli protein is blocked in V12Ras and p110alpha transformants though no changes in glycogen synthase kinase 3 beta activity could be detected. Nevertheless, in V12Ras transformants the in vivo phosphorylation of beta-catenin in Ser residues is strongly decreased. These results indicate that H-Ras activation induces the relocalization and cytoplasmic stabilization of beta-catenin by a mechanism involving its interaction with PI3K.
Assuntos
Citoplasma/metabolismo , Proteínas do Citoesqueleto/metabolismo , Queratinócitos/metabolismo , Proteína Oncogênica p21(ras)/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transativadores , Proteína da Polipose Adenomatosa do Colo , Animais , Caderinas/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Transformação Celular Neoplásica , Ativação Enzimática , Quinase 3 da Glicogênio Sintase , Quinases da Glicogênio Sintase , Queratinócitos/citologia , Queratinócitos/enzimologia , Camundongos , Microinjeções , Proteína Oncogênica p21(ras)/genética , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Fosfosserina/análise , Fosfosserina/metabolismo , Fosfotirosina/análise , Ligação Proteica , alfa Catenina , beta CateninaRESUMO
OBJECTIVE: To estimate incidence rates and risk factors for tuberculosis (TB) in human immunodeficiency virus seroprevalent subjects. METHODS: Multicentre, hospital-based cohort study of patients presenting to 10 Spanish hospitals from 1 January 1997 to 31 December 2003. Poisson regression was used and highly active antiretroviral treatment (HAART) was modelled as a time-dependent covariate. RESULTS: A total of 4268 patients were followed for a median of 3.8 years; 221 TB cases were diagnosed over 16 464 person-years (py). TB rates were higher in HAART-naïve subjects (1.56 per 100 py, 95%CI 1.36-1.79) than those on HAART (0.5/100 py, 95%CI 0.31-0.80). Among HAART-naïves, TB risk factors were: being male, being an injecting drug user (IDU) (RR 2.01, 95%CI 1.28-3.16), having low CD4 counts (P < 0.001) and high viral loads (P < 0.001). HAART was protective (RR 0.26, 95%CI 0.16-0.40) and reductions in TB rates were observed in the last calendar period (RR 0.74, 95%CI 0.55-1.00). For patients on HAART, no differences were observed by category of transmission. Low CD4 counts at entry were associated with higher TB rates (P < 0.001). CONCLUSIONS: HAART was associated with lower TB rates, and TB risk factors differed according to whether or not patients had received HAART. To further reduce TB rates, additional strategies are needed, such as timely access and adherence to HAART, especially in IDUs.
Assuntos
Terapia Antirretroviral de Alta Atividade , Soropositividade para HIV/complicações , Soropositividade para HIV/tratamento farmacológico , Tuberculose/epidemiologia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Fatores de Risco , Tuberculose/etiologiaRESUMO
We have isolated spontaneous mutants of polyoma virus middle T-antigen (PyMT) that do not activate the ARF-p53 pathway based on their inability to block REF52 cell division. The REF52 cells containing these mutants have a flat untransformed morphological phenotype and do not express the ARF protein. The PyMT mutations in the different cell isolates so far analysed occur at a mutational hotspot in the PyMT sequence between nucleotides 1241 and 1249, which contains nine consecutive cytosines. In one set of mutants a single cytosine was deleted, while in another mutant set an additional cytosine was inserted. Both these mutations result in frameshifts, generating altered PyMT proteins containing amino-acid sequences derived from each of the two other alternative reading frames of the polyoma virus early region. Both types of mutations result in the loss of the C-terminal PyMT region containing the membrane-binding hydrophobic region and result is mislocalization of the PyMT mutant proteins. Revertant wild-type PyMT (containing nine cytosines) was easily detected in transformants generated after infection of REF52 cells expressing high amounts of dominant negative p53 with retroviruses containing either mutation. We demonstrate that wild-type PyMT revertants are derived from mutations in the hotspot sequence of the integrated mutant PyMT sequences.
Assuntos
Antígenos Transformantes de Poliomavirus/genética , Instabilidade Cromossômica/genética , Mutação da Fase de Leitura , Transdução de Sinais/genética , Proteína Supressora de Tumor p14ARF/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Sequência de Aminoácidos , Animais , Antígenos Transformantes de Poliomavirus/fisiologia , Sequência de Bases , Linhagem Celular , Citosina , Regulação da Expressão Gênica/genética , Dados de Sequência Molecular , Polyomavirus/genética , Ratos , Deleção de SequênciaRESUMO
BACKGROUND: The small GTPase R-Ras displays a less potent transforming activity than the closely related Ras oncogene products. Although R-Ras has been reported to interact with c-Raf1 and Ral-GDS in vitro, the pathways by which it exerts its effects on cellular proliferation are not known. RESULTS: Both Ras and R-Ras interact with phosphoinositide (PI) 3-kinase in vitro, and induce elevation of the levels of PI 3-kinase lipid products in intact cells. Unlike Ras, R-Ras does not activate Raf or mitogen-activated protein (MAP) kinase in cells. In co-transfection assays, the serine/threonine protein kinase PKB (or Akt) is effectively stimulated by R-Ras, Ras, mutants of Ras that activate PI 3-kinase but not other effectors, and activated forms of PI 3-kinase. Ras and R-Ras stimulate PKB/Akt through a non-autocrine mechanism that involves PI 3-kinase. The constitutive activation of PI 3-kinase alone is sufficient to activate PKB/Akt, but not the MAP kinase ERK or the stress-activated protein kinase, Jun N-terminal kinase. Transformation assays in fibroblasts suggest that PKB/Akt and Raf are part of distinct oncogenic signalling pathways. CONCLUSIONS: Both the Raf-MAP kinase and PI 3-kinase-PKB/Akt pathways are activated by Ras, but only the PI 3-kinase-PKB/Akt pathway is activated by R-Ras. PI 3-kinase, and downstream targets such as PKB/Akt, are likely to be essential mediators of transformation induced by R-Ras. PI 3-kinase, as well as Raf, is thus implicated also in Ras transformation.
Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/efeitos dos fármacos , GTP Fosfo-Hidrolases/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/efeitos dos fármacos , Proteínas ras/farmacologia , Animais , Transformação Celular Neoplásica/metabolismo , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica/fisiologia , Camundongos , Fosfatidilinositol 3-QuinasesRESUMO
BACKGROUND: Activation of the mammalian phosphatidylinositol 3-kinase complex can play a critical role in transducing growth factor responses. The lipid kinase complex, which is made up of p85 alpha and p110 alpha regulatory and catalytic subunits, becomes associated with a number of activated receptor protein tyrosine kinases, but the mechanism of its activation has not yet been defined. Recent evidence indicates that Ras can bind to the p85 alpha/p110 alpha complex. We describe here the functional regulation of the mammalian phosphatidylinositol 3-kinase complex by Ras. RESULTS: Expression of p110 alpha, the catalytic subunit of phosphatidylinositol 3-kinase, in the fission yeast, Schizosaccharomyces pombe, has been used to demonstrate an inhibitory effect of p85 alpha on p110 alpha activity in intact cells; inhibition did not result from a decrease in p110 alpha expression. In this cellular context, we have investigated the effect of a constitutively active mutant of Ras, v-Ras, either on p85 alpha or p110 alpha-alone, or on the p85 alpha/p110 alpha complex. In the presence of the p85 alpha/p110 alpha complex, v-Ras suppressed cell growth, but an effector-domain mutant of v-Ras did not. The growth-suppressive effect of v-Ras was not seen for any other combination of expressed proteins. The phenotype induced by v-Ras was consistent with activation of the p85 alpha/p110 alpha complex: it was sensitive to the phosphatidylinositol 3-kinase inhibitor, wortmannin, and the cells accumulated 3-phosphorylated polyphosphoinositides. Activation of purified p85 alpha/p110 alpha by purified recombinant Ras in vitro was also demonstrated. CONCLUSIONS: The phosphatidylinositol 3-kinase complex, p85 alpha/p110 alpha, shows a suppressed catalytic function in vivo when compared with free p110 alpha. This complex can, however, be activated by Ras. We suggest that the phosphatidylinositol 3-kinase p85 alpha/p110 alpha complex is a downstream effector of Ras.
Assuntos
Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas ras/farmacologia , Animais , Bovinos , Ativação Enzimática/efeitos dos fármacos , Expressão Gênica , Técnicas In Vitro , Fosfatidilinositol 3-Quinases , Fosfotransferases (Aceptor do Grupo Álcool)/química , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Conformação Proteica , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética , Transdução de Sinais , Proteínas ras/genéticaRESUMO
OBJECTIVE: To study the prevalence of Mycobacterium tuberculosis infection (MTBI) and past/current tuberculosis (TB) among human immunodeficiency virus (HIV) infected persons in Spain. DESIGN: Longitudinal study conducted between 2000 and 2003 at 10 HIV hospital-based clinics. Data were drawn from clinical records. Associations were measured using odds ratios (ORs) and their 95% confidence intervals (95%CI). RESULTS: Of the 1242 persons who met the eligibility criteria, most were male (75%), aged <40 years (75%) and unemployed (40%). HIV infection occurred through intravenous drug use (53%), heterosexual sex (29%) and sex between men (16%). In the initial evaluation, 315 subjects had evidence of MTBI: 84 (6.8%) had a history of TB, 23 (1.8%) current TB and 208 (16.8%) latent tuberculosis infection (LTBI). MTBI was associated with male sex, age 30-49 years, contact with a TB case, homelessness, poor education, and negatively with CD4 <100 cells/mm(3). Among subjects with MTBI, past/current TB was associated with retirement/disability (OR 6, 95%CI 1.6-22.5), CD4 <200 cells/mm(3) (OR 9.7, 95%CI 3.8-24.6), viral load >55,000 copies (OR 5.3, 95%CI 1.4-20.0), and negatively, with skilled work (OR 0.4, 95%CI 0.1-1.0) or administrative/managerial/professional work (OR 0.05, 95%CI 0.01-0.4). CONCLUSION: Social context has an impact on the effectiveness of HIV and TB control programmes even in industrialised countries with free access to health care.
Assuntos
Infecções por HIV/complicações , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/epidemiologia , Adulto , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prevalência , Fatores de Risco , Espanha/epidemiologia , Tuberculose/complicações , Tuberculose/diagnósticoRESUMO
Madin-Darby canine kidney (MDCK) epithelial cells transformed by oncogenic Ras and Raf exhibit cell multilayering and alterations in the actin cytoskeleton. The changes in the actin cytoskeleton comprise a loss of actin stress fibers and enhanced cortical actin. Using MDCK cells expressing a conditionally active form of Raf, we have explored the molecular mechanisms that underlie these observations. Raf activation elicited a robust increase in Rac1 activity consistent with the observed increase in cortical actin. Loss of actin stress fibers is indicative of attenuated Rho function, but no change in Rho-GTP levels was detected following Raf activation. However, the loss of actin stress fibers in Raf-transformed cells was preceded by the induced expression of Rnd3, an endogenous inhibitor of Rho protein function. Expression of Rnd3 alone at levels equivalent to those observed following Raf transformation led to a substantial loss of actin stress fibers. Moreover, cells expressing activated RhoA failed to multilayer in response to Raf. Pharmacological inhibition of MEK activation prevented all of the biological and biochemical changes described above. Consequently, the data are consistent with a role for induced Rnd3 expression downstream of the Raf-MEK-extracellular signal-regulated kinase pathway in epithelial oncogenesis.
Assuntos
Transformação Celular Neoplásica , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais , Tamoxifeno/análogos & derivados , Proteínas rho de Ligação ao GTP/metabolismo , Actinas/imunologia , Actinas/metabolismo , Animais , Western Blotting , Caderinas/imunologia , Caderinas/metabolismo , Fracionamento Celular , Linhagem Celular , Polaridade Celular , Citoesqueleto/metabolismo , Cães , Ecdisona/análogos & derivados , Ecdisona/farmacologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/enzimologia , Antagonistas de Estrogênios/farmacologia , Junções Intercelulares , Microscopia Confocal , Testes de Precipitina , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-raf/química , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologiaRESUMO
Cross-sectional study comparing seminal human immunodeficiency virus type 1 (HIV-1) shedding in patients receiving boosted protease inhibitor monotherapy (mtPI/rtv) (n = 66) versus triple therapy (TT) (n = 61). Seminal HIV-1 shedding rates in patients with undetectable plasma HIV-RNA were 16.0% on mtPI/rtv compared with 28.6% on TT (p 0.173). Aviraemic status and time on viral suppression were independently associated with lack of seminal HIV-1 shedding. During TT, non PI/rtv-based regimens were associated with a better control of HIV infection in semen despite similar time on viral suppression. The use of mtPI/rtv in well-controlled patients is not associated with increased seminal HIV excretion compared with TT.
Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Inibidores da Protease de HIV/uso terapêutico , HIV-1/isolamento & purificação , Sêmen/virologia , Eliminação de Partículas Virais/efeitos dos fármacos , Adulto , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: Fever of intermediate duration (FID), characterized by a febrile syndrome lasting from 7 to 28 days, is a frequent condition in clinical practice, but its epidemiological and etiologic features are not well described. Murine typhus (MT) is a worldwide illness; nevertheless, to our knowledge, no studies describing its epidemiological and clinical characteristics have been performed in the south of Spain. Also, its significance as a cause of FID is unknown. OBJECTIVE: To determine the epidemiological features, clinical characteristics, and prognosis of MT and, prospectively, its incidence as a cause of FID. DESIGN: Prospective study of cases of MT over 17 years (1979-1995) and of all cases of FID treated in a tertiary teaching hospital in Seville, Spain. RESULTS: One hundred and four cases of MT were included, and MT was the cause in 6.7% of 926 cases of FID. Insect bites were reported in only 3.8% of the cases of MT previous to the onset of illness. Most cases (62.5%) occurred in the summer and fall. A high frequency of rash (62.5%) was noted. Arthromyalgia (77%), headache (71%), and respiratory (25%) and gastrointestinal (23%) symptoms were also frequent. Laboratory findings were unspecific. Organ complications were uncommon (8.6%), but they were severe in 4 cases. The mean duration of fever was 12.5 days. Cure was achieved in all cases, although only 44 patients received specific treatment. CONCLUSIONS: Murine typhus is prevalent in the south of Spain and is a significant cause of FID. Clinical signs are benign, but some patients may develop severe complications. A high degree of clinical suspicion is required for diagnosis.
Assuntos
Febre/microbiologia , Camundongos/microbiologia , Tifo Epidêmico Transmitido por Piolhos/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Antibacterianos/sangue , Criança , Febre/epidemiologia , Febre/imunologia , Fluorimunoensaio , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Rickettsia typhi/imunologia , Estações do Ano , Espanha/epidemiologia , Fatores de Tempo , Tifo Epidêmico Transmitido por Piolhos/epidemiologia , Tifo Epidêmico Transmitido por Piolhos/imunologiaRESUMO
We characterized transmitted drug resistance to rilpivirine and the predicted efficacy of first-line rilpivirine-containing regimens in antiretroviral-naive Spanish patients. International Antiviral Society-USA mutations were detected in 138 of 2781 patients (4.9%), E138A (3.4%) being the most prevalent. Using the Stanford Algorithm, 121 patients (4.4%) showed low-level or intermediate resistance. No differences in the predicted efficacy of first-line non-nucleoside reverse transcriptase inhibitor-based regimens were observed. As rilpivirine becomes more widely used in clinical practice, the evolution of its transmitted drug resistance will need to be monitored. In addition, the exact role of E138A singletons on rilpivirine activity as part of first-line regimens merits further evaluation.