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1.
HIV Med ; 22(5): 346-359, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33368946

RESUMEN

OBJECTIVES: Understanding the drivers of HIV-1 transmission is of importance for curbing the ongoing epidemic. Phylogenetic methods based on single viral sequences allow us to assess whether two individuals are part of the same viral outbreak, but cannot on their own assess who potentially transmitted the virus. We developed and assessed a molecular epidemiology method with the main aim to screen cohort studies for and to characterize individuals who are 'potential HIV-1 transmitters', in order to understand the drivers of HIV-1 transmission. METHODS: We developed and validated a molecular epidemiology approach using longitudinally sampled viral Sanger sequences to characterize potential HIV-1 transmitters in the Swiss HIV Cohort Study. RESULTS: Our method was able to identify 279 potential HIV-1 transmitters and allowed us to determine the main epidemiological and virological drivers of transmission. We found that the directionality of transmission was consistent with infection times for 72.9% of 85 potential HIV-1 transmissions with accurate infection date estimates. Being a potential HIV-1 transmitter was associated with risk factors including viral load [adjusted odds ratiomultivariable (95% confidence interval): 1.86 (1.49-2.32)], syphilis coinfection [1.52 (1.06-2.19)], and recreational drug use [1.45 (1.06-1.98)]. By contrast for the potential HIV-1 recipients, this association was weaker or even absent [1.18 (0.82-1.72), 0.89 (0.52-1.55) and 1.53 (0.98-2.39), respectively], indicating that inferred directionality of transmission is useful at the population level. CONCLUSIONS: Our results indicate that longitudinally sampled Sanger sequences do not provide sufficient information to identify transmitters with high certainty at the individual level, but that they allow the drivers of transmission at the population level to be characterized.


Asunto(s)
Infecciones por VIH , VIH-1 , Secuencia de Bases , Estudios de Cohortes , VIH-1/genética , Humanos , Filogenia
2.
HIV Med ; 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29932298

RESUMEN

OBJECTIVES: Dolutegravir (DTG) is a highly effective integrase inhibitor with a strong genetic resistance barrier and a potential role in simplified HIV maintenance treatment. We assessed the feasibility of DTG maintenance monotherapy and measured HIV reservoirs on DTG monotherapy. METHODS: An interventional, open-label, single-arm study including eight virologically suppressed HIV-1-infected patients switched to DTG 50 mg once daily for 24 weeks was performed. HIV-1 RNA levels in plasma and cerebrospinal and seminal fluids were measured at baseline and week 24, as well as HIV-1 DNA in peripheral cells and DTG concentrations in these compartments. RESULTS: HIV-1 RNA remained undetectable in all samples of blood, cerebrospinal fluid and sperm throughout the 24 weeks, except for one cerebrospinal fluid sample with a value of 28 HIV-1 RNA copies/mL at week 24. One patient discontinued the study because of a neurological side effect. There was no change in the mean HIV-1 DNA level between baseline and week 24. Plasma and cerebrospinal fluid DTG concentrations reached therapeutic levels in all patients in these two compartments. CONCLUSIONS: In this small sample of carefully selected patients, HIV-1 reservoirs were well controlled on DTG monotherapy over a period of 24 weeks. Viral suppression was also maintained throughout follow-up.

3.
HIV Med ; 19(6): 420-425, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29573533

RESUMEN

OBJECTIVES: Following clearance of incident hepatitis C virus (HCV) infections, HCV antibody levels may decline, resulting in seroreversion. It is unclear to what extent HCV antibody level trajectories differ between patients with treatment-induced sustained virological response (SVR), those with spontaneous clearance and those with untreated replicating HCV infection. We investigated HCV antibody level dynamics in HIV-infected MSM with different clinical outcomes. METHODS: We investigated anti-HCV antibody level dynamics following an incident HCV infection in 67 HIV-infected men who have sex with men (MSM) with different clinical outcomes: SVR (n = 33), spontaneous clearance (n = 12), and untreated replicating infection (n = 22). Antibody levels were measured at the time of HCV diagnosis, and at yearly intervals for 3 years thereafter. RESULTS: At baseline, median HCV antibody levels were similar in the three groups: 13.4, 13.8 and 13.5 sample to cut-off (S/CO) for SVR, spontaneous clearance and untreated infection, respectively. Over 3 years of follow-up, SVR was associated with a more pronounced decrease in anti-HCV levels compared with spontaneous clearance and untreated infection [median decline 71% [interquartile range (IQR: 43-87%), 38% (IQR: 29-60%) and 12% (IQR: 9-22%), respectively; P < 0.001]. Seroreversions occurred in five of 33 (15%) patients with SVR and in one of 12 (8%) with spontaneous clearance. A shorter delay between time of infection and treatment start correlated with higher rates of decline in antibody levels. Seven patients experienced a reinfection. CONCLUSIONS: Treatment-induced HCV clearance was associated with a more pronounced decline in anti-HCV antibody levels and with higher rates of seroreversion compared with spontaneous clearance or untreated replicating HCV infection among HIV-infected MSM with incident HCV infections. Rapid clearance of HCV RNA following early HCV treatment might impair the development of persistent antibody titres.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Antivirales/uso terapéutico , Infecciones por VIH/complicaciones , Anticuerpos contra la Hepatitis C/efectos de los fármacos , Anticuerpos contra la Hepatitis C/inmunología , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Homosexualidad Masculina , Adulto , Coinfección , Quimioterapia Combinada , Estudios de Seguimiento , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Hepatitis C/inmunología , Humanos , Masculino , Remisión Espontánea , Respuesta Virológica Sostenida , Factores de Tiempo , Resultado del Tratamiento , Carga Viral , Replicación Viral/inmunología
4.
HIV Med ; 18(9): 667-676, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28378387

RESUMEN

OBJECTIVES: Here we examined the hypothesis that some stable HIV-infected partnerships can be found in cohort studies, as the patients frequently attend the clinic visits together. METHODS: Using mathematical approximations and shuffling to derive the probabilities of sharing a given number of visits by chance, we identified and validated couples that may represent either transmission pairs or serosorting couples in a stable relationship. RESULTS: We analysed 434 432 visits for 16 139 Swiss HIV Cohort Study patients from 1990 to 2014. For 89 pairs, the number of shared visits exceeded the number expected. Of these, 33 transmission pairs were confirmed on the basis of three criteria: an extensive phylogenetic tree, a self-reported steady HIV-positive partnership, and risk group affiliation. Notably, 12 of the validated transmission pairs (36%; 12 of 33) were of a mixed ethnicity with a large median age gap [17.5 years; interquartile range (IQR) 11.8-22 years] and these patients harboured HIV-1 of predominantly non-B subtypes, suggesting imported infections. CONCLUSIONS: In the context of the surge in research interest in HIV transmission pairs, this simple method widens the horizons of research on within-pair quasi-species exchange, transmitted drug resistance and viral recombination at the biological level and targeted prevention at the public health level.


Asunto(s)
Minería de Datos/métodos , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Parejas Sexuales/clasificación , Atención Ambulatoria/estadística & datos numéricos , Estudios de Cohortes , Femenino , Infecciones por VIH/etnología , Infecciones por VIH/virología , VIH-1/clasificación , Homosexualidad Femenina/etnología , Homosexualidad Masculina/etnología , Humanos , Masculino , Filogenia , Autoinforme , Nivel de Atención
5.
Clin Infect Dis ; 62(10): 1310-1317, 2016 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-26962075

RESUMEN

BACKGROUND: Drug resistance is a major barrier to successful antiretroviral treatment (ART). Therefore, it is important to monitor time trends at a population level. METHODS: We included 11 084 ART-experienced patients from the Swiss HIV Cohort Study (SHCS) between 1999 and 2013. The SHCS is highly representative and includes 72% of patients receiving ART in Switzerland. Drug resistance was defined as the presence of ≥1 major mutation in a genotypic resistance test. To estimate the prevalence of drug resistance, data for patients with no resistance test was imputed based on the patient's risk of harboring drug-resistant viruses. RESULTS: The emergence of new drug resistance mutations declined dramatically from 401 to 23 patients between 1999 and 2013. The upper estimated prevalence limit of drug resistance among ART-experienced patients decreased from 57.0% in 1999 to 37.1% in 2013. The prevalence of 3-class resistance decreased from 9.0% to 4.4% and was always <0.4% for patients who initiated ART after 2006. Most patients actively participating in the SHCS in 2013 with drug-resistant viruses initiated ART before 1999 (59.8%). Nevertheless, in 2013, 94.5% of patients who initiated ART before 1999 had good remaining treatment options based on Stanford algorithm. CONCLUSIONS: Human immunodeficiency virus type 1 drug resistance among ART-experienced patients in Switzerland is a well-controlled relic from the era before combination ART. Emergence of drug resistance can be virtually stopped with new potent therapies and close monitoring.


Asunto(s)
Farmacorresistencia Viral/genética , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/genética , Adulto , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Suiza/epidemiología
6.
Clin Infect Dis ; 62(1): 115-122, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26387084

RESUMEN

BACKGROUND: Reducing the fraction of transmissions during recent human immunodeficiency virus (HIV) infection is essential for the population-level success of "treatment as prevention". METHODS: A phylogenetic tree was constructed with 19 604 Swiss sequences and 90 994 non-Swiss background sequences. Swiss transmission pairs were identified using 104 combinations of genetic distance (1%-2.5%) and bootstrap (50%-100%) thresholds, to examine the effect of those criteria. Monophyletic pairs were classified as recent or chronic transmission based on the time interval between estimated seroconversion dates. Logistic regression with adjustment for clinical and demographic characteristics was used to identify risk factors associated with transmission during recent or chronic infection. FINDINGS: Seroconversion dates were estimated for 4079 patients on the phylogeny, and comprised between 71 (distance, 1%; bootstrap, 100%) to 378 transmission pairs (distance, 2.5%; bootstrap, 50%). We found that 43.7% (range, 41%-56%) of the transmissions occurred during the first year of infection. Stricter phylogenetic definition of transmission pairs was associated with higher recent-phase transmission fraction. Chronic-phase viral load area under the curve (adjusted odds ratio, 3; 95% confidence interval, 1.64-5.48) and time to antiretroviral therapy (ART) start (adjusted odds ratio 1.4/y; 1.11-1.77) were associated with chronic-phase transmission as opposed to recent transmission. Importantly, at least 14% of the chronic-phase transmission events occurred after the transmitter had interrupted ART. CONCLUSIONS: We demonstrate a high fraction of transmission during recent HIV infection but also chronic transmissions after interruption of ART in Switzerland. Both represent key issues for treatment as prevention and underline the importance of early diagnosis and of early and continuous treatment.


Asunto(s)
Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , Adulto , Algoritmos , Análisis por Conglomerados , Estudios de Cohortes , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/genética , Humanos , Masculino , Filogenia , Factores de Riesgo , Suiza/epidemiología
7.
J Antimicrob Chemother ; 70(3): 922-5, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25428920

RESUMEN

OBJECTIVES: The aim of this study was to describe clinical and virological outcomes in therapy-naive HIV-1-positive patients treated in a routine ART programme in rural Cameroon. METHODS: In a prospective cohort, 300 consecutive patients starting first-line ART were enrolled and followed for 12 months. Among 238 patients with available viral load data at Month 12, logistic regression was used to analyse risk factors for virological failure (≥1000 HIV RNA copies/mL) including clinical, immunological and virological parameters, as well as data on drug adherence. Population sequencing was performed to detect the presence of drug-resistance mutations in patients with virological failure at Month 12; minority drug-resistance mutations at baseline were analysed using next-generation sequencing in these patients and matched controls. RESULTS: At Month 12, 38/238 (16%) patients experienced virological failure (≥1000 HIV RNA copies/mL). Patients with virological failure were younger, had lower CD4 cell counts and were more often WHO stage 3 or 4 at baseline. Sixty-three percent of patients with virological failure developed at least one drug-resistance mutation. The M184V (n = 18) and K103N (n = 10) mutations were most common. At baseline, 6/30 patients (20%) experiencing virological failure and 6/35 (17%) matched controls had evidence of minority drug-resistance mutations using next-generation sequencing (P = 0.77). Lower CD4 count at baseline (OR per 100 cells/mm(3) lower 1.41, 95% CI 1.02-1.96, P = 0.04) and poorer adherence (OR per 1% lower 1.05, 95% CI 1.02-1.08, P < 0.001) were associated with a higher risk of virological failure. Unavailability of ART at the treatment centre was the single most common cause for incomplete adherence. CONCLUSIONS: Virological failure after 1 year of ART was not associated with minority drug resistance at baseline but with incomplete adherence. Strategies to assure adherence and uninterrupted drug supplies are pivotal factors for therapy success.


Asunto(s)
Antirretrovirales/uso terapéutico , Terapia Antirretroviral Altamente Activa , Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , VIH-1/aislamiento & purificación , Cumplimiento de la Medicación , Carga Viral , Adulto , Anciano , Camerún , Estudios de Cohortes , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Estudios Prospectivos , Población Rural , Análisis de Secuencia de ADN , Insuficiencia del Tratamiento , Adulto Joven
8.
Basic Res Cardiol ; 110(2): 5, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25600224

RESUMEN

The sustained component of the K(+) outward current in human atrial myocytes is believed to be due to the slowly inactivating ultra-rapid potassium current I Kur and not to the fast inactivating transient outward current Ito. Here we provide evidence for contribution of Ito to this late current due to the effects of dipeptidyl peptidase-like protein (DPP) 10 (DPP10a) interacting with Kv4.3 channels. We studied the late current component of Ito in human atrial myocytes and CHO cells co-expressing Kv4.3 or Kv4.3/KChIP2 (control) and DPP proteins using voltage-clamp technique and a pharmacological approach. A voltage dependent and slowly inactivating late current (43% of peak amplitude) could be observed in atrial myocytes. We found a similar current in CHO cells expressing Kv4.3/KChIP2 + DPP10a, but not in cells co-expressing Kv4.3 + DPP or Kv4.3/KChIP2 + DPP6-S. Assuming that DPP10a influences atrial Ito, we detected DPP10 expression of three alternatively spliced mRNAs, DPP10 protein and colocalization of Kv4.3 and DPP10 proteins in human atrial myocytes. DPP10a did not affect properties of expressed Kv1.5 excluding a contribution to the sustained IKur in atrial cells. To test for the contribution of Kv4-based Ito on sustained K(+) outward currents in human atrial myocytes, we used 4-AP to block IKur, in combination with Heteropoda toxin 2 to block Kv4 channels. We could clearly separate an Ito fraction of about 19% contributing to the late current in atrial myocytes. Thus, the interaction of DPP10a, expressed in human atrium, with Kv4.3 channels generates a sustained current component of Ito, which may affect late repolarization phase of atrial action potentials.


Asunto(s)
Potenciales de Acción/fisiología , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Miocitos Cardíacos/metabolismo , Canales de Potasio Shal/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Células CHO , Cricetulus , Femenino , Técnica del Anticuerpo Fluorescente , Atrios Cardíacos/metabolismo , Humanos , Masculino , Ratones , Persona de Mediana Edad , Técnicas de Placa-Clamp , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
9.
HIV Med ; 16(10): 599-607, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26135140

RESUMEN

OBJECTIVES: Direct-acting antiviral agents (DAAs) have become the standard of care for the treatment of chronic hepatitis C virus (HCV) infection. We aimed to assess treatment uptake and efficacy in routine clinical settings among HIV/HCV coinfected patients after the introduction of the first generation DAAs. METHODS: Data on all Swiss HIV Cohort Study (SHCS) participants starting HCV protease inhibitor (PI) treatment between September 2011 and August 2013 were collected prospectively. The uptake and efficacy of HCV therapy were compared with those in the time period before the availability of PIs. RESULTS: Upon approval of PI treatment in Switzerland in September 2011, 516 SHCS participants had chronic HCV genotype 1 infection. Of these, 57 (11%) started HCV treatment during the following 2 years with either telaprevir, faldaprevir or boceprevir. Twenty-seven (47%) patients were treatment-naïve, nine (16%) were patients with relapse and 21 (37%) were partial or null responders. Twenty-nine (57%) had advanced fibrosis and 15 (29%) had cirrhosis. End-of-treatment virological response was 84% in treatment-naïve patients, 88% in patients with relapse and 62% in previous nonresponders. Sustained virological response was 78%, 86% and 40% in treatment-naïve patients, patients with relapse and nonresponders, respectively. Treatment uptake was similar before (3.8 per 100 patient-years) and after (6.1 per 100 patient-years) the introduction of PIs, while treatment efficacy increased considerably after the introduction of PIs. CONCLUSIONS: The introduction of PI-based HCV treatment in HIV/HCV-coinfected patients improved virological response rates, while treatment uptake remained low. Therefore, the introduction of PIs into the clinical routine was beneficial at the individual level, but had only a modest effect on the burden of HCV infection at the population level.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por VIH/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Aceptación de la Atención de Salud/estadística & datos numéricos , Inhibidores de Proteasas/uso terapéutico , Adulto , Ácidos Aminoisobutíricos , Estudios de Cohortes , Femenino , Humanos , Leucina/análogos & derivados , Masculino , Persona de Mediana Edad , Oligopéptidos/uso terapéutico , Prolina/análogos & derivados , Prolina/uso terapéutico , Estudios Prospectivos , Quinolinas , ARN Viral/análisis , Suiza , Tiazoles/uso terapéutico , Carga Viral
10.
J Fish Biol ; 87(2): 487-93, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26111728

RESUMEN

After stocking with larvae from the Gironde-Garonne-Dordogne population, in 2013, three young-of-the-year Allis shad Alosa alosa, probably originating from natural reproduction, were documented for the first time in a period of nearly 100 years in the River Rhine. In 2014, a further increase was observed when 57 juveniles and eight adults were caught; seven of these eight adults were derived from stocking, indicating the success of stocking measures within the framework of the EU-LIFE project.


Asunto(s)
Peces/fisiología , Reproducción , Migración Animal , Animales , Conservación de los Recursos Naturales , Femenino , Alemania , Masculino , Densidad de Población , Ríos
11.
HIV Med ; 15(10): 625-30, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24894776

RESUMEN

OBJECTIVES: The efficacy of current hepatitis C virus (HCV) triple therapy, including a protease inhibitor, is limited in HIV/HCV-coinfected patients with advanced liver fibrosis and nonresponse to previous peginterferon-ribavirin. These patients have a low chance (only 30%) of achieving a sustained virological response (SVR) during triple therapy and cannot wait for next-generation anti-HCV drugs. In a pilot study, we investigated the efficacy of a lead-in therapy with silibinin before triple therapy in difficult-to-treat patients. METHODS: Inclusion criteria were HIV/HCV coinfection with advanced liver fibrosis and documented failure of previous peginterferon-ribavirin treatment. Intervention was lead-in therapy with intravenous silibinin 20 mg/kg/day for 14 days. Subsequently, peginterferon-ribavirin combined with telaprevir was initiated for 12 weeks, followed by peginterferon-ribavirin dual therapy until week 48 after initiation of triple therapy. The outcome measurements were HCV RNA after silibinin lead-in, at weeks 2, 4 and 12 of triple therapy, and SVR at week 24 after the end of treatment. RESULTS: We examined six HIV/HCV-coinfected patients (four infected with genotype 1a). All had fibrosis grade METAVIR ≥F3 and were on fully suppressive antiretroviral therapy. Mean HCV RNA decline after silibinin therapy was 2.6 log10 IU/mL (range 2-3 log10 IU/mL). Five of the six patients were virologically suppressed at weeks 2 and 4, and all six at week 12 of triple therapy. One experienced a viral breakthrough thereafter. Four of five patients (80%) showed an SVR 24. One patient had an SVR 12 but has not yet reached week 24. CONCLUSIONS: A lead-in with silibinin before triple therapy is highly effective and increases the probability of HCV treatment success in difficult-to-treat HIV/HCV-coinfected patients with advanced liver fibrosis and previous failure of peginterferon-ribavirin.


Asunto(s)
Antivirales/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , Hepatitis C/tratamiento farmacológico , Silimarina/administración & dosificación , Adulto , Antirretrovirales/uso terapéutico , Antivirales/efectos adversos , Coinfección/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Infecciones por VIH/complicaciones , Hepatitis C/complicaciones , Humanos , Inyecciones Intravenosas , Cirrosis Hepática/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Proyectos Piloto , Inhibidores de Proteasas/administración & dosificación , ARN Viral/análisis , Silibina , Silimarina/efectos adversos
12.
J Exp Med ; 191(11): 1921-31, 2000 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-10839807

RESUMEN

The role of CD8(+) T lymphocytes in controlling replication of live, attenuated simian immunodeficiency virus (SIV) was investigated as part of a vaccine study to examine the correlates of protection in the SIV/rhesus macaque model. Rhesus macaques immunized for >2 yr with nef-deleted SIV (SIVmac239Deltanef) and protected from challenge with pathogenic SIVmac251 were treated with anti-CD8 antibody (OKT8F) to deplete CD8(+) T cells in vivo. The effects of CD8 depletion on viral load were measured using a novel quantitative assay based on real-time polymerase chain reaction using molecular beacons. This assay allows simultaneous detection of both the vaccine strain and the challenge virus in the same sample, enabling direct quantification of changes in each viral population. Our results show that CD8(+) T cells were depleted within 1 h after administration of OKT8F, and were reduced by as much as 99% in the peripheral blood. CD8(+) T cell depletion was associated with a 1-2 log increase in SIVmac239Deltanef plasma viremia. Control of SIVmac239Deltanef replication was temporally associated with the recovery of CD8(+) T cells between days 8 and 10. The challenge virus, SIVmac251, was not detectable in either the plasma or lymph nodes after depletion of CD8(+) T cells. Overall, our results indicate that CD8(+) T cells play an important role in controlling replication of live, attenuated SIV in vivo.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Vacunas Virales/inmunología , Replicación Viral/inmunología , Animales , Antígenos CD20/inmunología , ADN Viral/sangre , Ganglios Linfáticos/patología , Ganglios Linfáticos/virología , Depleción Linfocítica , Macaca mulatta , ARN Viral/sangre , Receptores de IgG/inmunología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/fisiología , Vacunación , Vacunas Atenuadas , Carga Viral
13.
Clin Microbiol Infect ; 22(2): 191-200, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26482266

RESUMEN

Plasma drug-resistant minority human immunodeficiency virus type 1 variants (DRMVs) increase the risk of virological failure to first-line non-nucleoside reverse transcriptase inhibitor antiretroviral therapy (ART). The origin of DRMVs in ART-naive patients, however, remains unclear. In a large pan-European case-control study investigating the clinical relevance of pre-existing DRMVs using 454 pyrosequencing, the six most prevalent plasma DRMVs detected corresponded to G-to-A nucleotide mutations (V90I, V106I, V108I, E138K, M184I and M230I). Here, we evaluated if such DRMVs could have emerged from apolipoprotein B mRNA editing enzyme, catalytic polypeptide 3G/F (APOBEC3G/F) activity. Out of 236 ART-naive subjects evaluated, APOBEC3G/F hypermutation signatures were detected in plasma viruses of 14 (5.9%) individuals. Samples with minority E138K, M184I, and M230I mutations, but not those with V90I, V106I or V108I, were significantly associated with APOBEC3G/F activity (Fisher's P < 0.005), defined as the presence of > 0.5% of sample sequences with an APOBEC3G/F signature. Mutations E138K, M184I and M230I co-occurred in the same sequence as APOBEC3G/F signatures in 3/9 (33%), 5/11 (45%) and 4/8 (50%) of samples, respectively; such linkage was not found for V90I, V106I or V108I. In-frame STOP codons were observed in 1.5% of all clonal sequences; 14.8% of them co-occurred with APOBEC3G/F signatures. APOBEC3G/F-associated E138K, M184I and M230I appeared within clonal sequences containing in-frame STOP codons in 2/3 (66%), 5/5 (100%) and 4/4 (100%) of the samples. In a re-analysis of the parent case control study, the presence of APOBEC3G/F signatures was not associated with virological failure. In conclusion, the contribution of APOBEC3G/F editing to the development of DRMVs is very limited and does not affect the efficacy of non-nucleoside reverse transcriptase inhibitor ART.


Asunto(s)
Citidina Desaminasa/genética , Citosina Desaminasa/genética , Farmacorresistencia Viral , Infecciones por VIH/virología , VIH-1/genética , Mutación , Desaminasa APOBEC-3G , Terapia Antirretroviral Altamente Activa , Estudios de Casos y Controles , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , Humanos , Masculino , Edición de ARN , ARN Viral/genética , ARN Viral/metabolismo , Inhibidores de la Transcriptasa Inversa/uso terapéutico
14.
Mol Immunol ; 34(8-9): 619-29, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9393965

RESUMEN

A high percentage of birch pollen allergic patients experiences food hypersensitivity reactions after ingestion of several fruits and vegetables. Previous work demonstrated common epitopes on an allergen of Mr 18,000 from sweet cherry (Prunus avium) and Bet v 1, the major allergen from birch pollen. N-terminal amino acid sequencing showed a sequence identity of 67% with Bet v 1. Here we report the cloning and cDNA sequencing of this cherry allergen. The entire deduced amino acid sequence described a protein of Mr 17,700 with 59.1% identity to Bet v 1. High degrees of identity in the range of 40 to 60% were also found with related allergens from other kinds of tree pollen and plant foods as well as with stress-induced proteins from food plants such as parsley, potato and soya. The coding DNA of the cherry protein was cloned into vector pET-16b and expressed in E. coli strain BL21(DE3) as a His-tag fusion protein. As shown by SDS-PAGE, the apparent molecular masses of the nonfusion protein and the natural allergen were identical. The fusion protein showed high IgE binding potency when sera from patients allergic to cherry were tested by immunoblotting and enzyme allergosorbent tests. Moreover, it cross-reacted strongly with IgE specific for the natural counterpart and for Bet v 1. The high biological activity of the recombinant fusion protein was further confirmed by the induction of a strong histamine release in basophils from cherry-allergic patients. Since sera from 17/19 of such patients contained IgE against this allergen it was classified as a major allergen and named Pru a 1. Recombinant Pru a 1 mimics most of the allergenic potency of cherry extract and hence could be a useful tool for studying the molecular and immunological properties of pollen related food allergens.


Asunto(s)
Alérgenos/genética , Frutas/química , Proteínas de Plantas/genética , Alérgenos/química , Alérgenos/inmunología , Secuencia de Aminoácidos , Antígenos de Plantas , Secuencia de Bases , Clonación Molecular , Frutas/genética , Frutas/inmunología , Expresión Génica , Genes de Plantas , Humanos , Inmunoglobulina E/metabolismo , Datos de Secuencia Molecular , Proteínas de Plantas/química , Proteínas de Plantas/inmunología , Alineación de Secuencia
15.
Open Forum Infect Dis ; 2(2): ofv077, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26180827

RESUMEN

Condomless sex is a key driver of sexually transmitted diseases. In this study, we assess the long-term changes (2000-2013) of the occurrence of condomless sex among human immunodeficiency virus (HIV)-infected individuals enrolled in the Swiss HIV Cohort study. The frequencies with which HIV-infected individuals reported condomless sex were either stable or only weakly increasing for 2000-2008. For 2008-2013, these rates increased significantly for stable relationships among heterosexuals and men who have sex with men (MSM) and for occasional relationships among MSM. Our results highlight the increasing public health challenge posed by condomless sex and show that condomless sex has been increasing even in the most recent years.

16.
Open Forum Infect Dis ; 2(3): ofv108, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26284258

RESUMEN

Background. Although acquired immune deficiency syndrome-associated morbidity has diminished due to excellent viral control, multimorbidity may be increasing among human immunodeficiency virus (HIV)-infected persons compared with the general population. Methods. We assessed the prevalence of comorbidities and multimorbidity in participants of the Swiss HIV Cohort Study (SHCS) compared with the population-based CoLaus study and the primary care-based FIRE (Family Medicine ICPC-Research using Electronic Medical Records) records. The incidence of the respective endpoints were assessed among SHCS and CoLaus participants. Poisson regression models were adjusted for age, sex, body mass index, and smoking. Results. Overall, 74 291 participants contributed data to prevalence analyses (3230 HIV-infected; 71 061 controls). In CoLaus, FIRE, and SHCS, multimorbidity was present among 26%, 13%, and 27% of participants. Compared with nonsmoking individuals from CoLaus, the incidence of cardiovascular disease was elevated among smoking individuals but independent of HIV status (HIV-negative smoking: incidence rate ratio [IRR] = 1.7, 95% confidence interval [CI] = 1.2-2.5; HIV-positive smoking: IRR = 1.7, 95% CI = 1.1-2.6; HIV-positive nonsmoking: IRR = 0.79, 95% CI = 0.44-1.4). Compared with nonsmoking HIV-negative persons, multivariable Poisson regression identified associations of HIV infection with hypertension (nonsmoking: IRR = 1.9, 95% CI = 1.5-2.4; smoking: IRR = 2.0, 95% CI = 1.6-2.4), kidney (nonsmoking: IRR = 2.7, 95% CI = 1.9-3.8; smoking: IRR = 2.6, 95% CI = 1.9-3.6), and liver disease (nonsmoking: IRR = 1.8, 95% CI = 1.4-2.4; smoking: IRR = 1.7, 95% CI = 1.4-2.2). No evidence was found for an association of HIV-infection or smoking with diabetes mellitus. Conclusions. Multimorbidity is more prevalent and incident in HIV-positive compared with HIV-negative individuals. Smoking, but not HIV status, has a strong impact on cardiovascular risk and multimorbidity.

17.
Open Forum Infect Dis ; 2(1): ofv026, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26034775

RESUMEN

Background. The hepatitis C virus (HCV) epidemic is evolving rapidly in patients infected with human immunodeficiency virus (HIV). We aimed to describe changes in treatment uptake and outcomes of incident HCV infections before and after 2006, the time-point at which major changes in HCV epidemic became apparent. Methods. We included all adults with an incident HCV infection before June 2012 in the Swiss HIV Cohort Study, a prospective nationwide representative cohort of individuals infected with HIV. We assessed the following outcomes by time period: the proportion of patients starting an HCV therapy, the proportion of treated patients achieving a sustained virological response (SVR), and the proportion of patients with persistent HCV infection during follow-up. Results. Of 193 patients with an HCV seroconversion, 106 were diagnosed before and 87 after January 2006. The proportion of men who have sex with men increased from 24% before to 85% after 2006 (P < .001). Hepatitis C virus treatment uptake increased from 33% before 2006 to 77% after 2006 (P < .001). Treatment was started during early infection in 22% of patients before and 91% after 2006 (P < .001). An SVR was achieved in 78% and 29% (P = .01) of patients treated during early and chronic HCV infection. The probability of having a detectable viral load 5 years after diagnosis was 0.67 (95% confidence interval [CI], 0.58-0.77) in the group diagnosed before 2006 and 0.24 (95% CI, 0.16-0.35) in the other group (P < .001). Conclusions. In recent years, increased uptake and earlier initiation of HCV therapy among patients with incident infections significantly reduced the proportion of patients with replicating HCV.

18.
Naunyn Schmiedebergs Arch Pharmacol ; 333(4): 381-6, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3774018

RESUMEN

The subcutaneous administration of a single dose of an opiate agonist (levorphanol) or antagonist (naloxone) to guinea pigs results in an at least 3-fold elevation of dynorphin and alpha-neoendorphin-immunoreactivity in the longitudinal muscle myenteric plexus preparation. The effects are time- and dose-dependent, significant elevations first being observed 6 h after treatment and lasting for up to 24 h. Pretreatment levels of opioid peptides were observed after 8 days. Combined injection of the narcotic agonist and antagonist, at sufficiently high doses, resulted in an additive effect of the individual drugs. The respective stereoisomers dextrorphan and (+)-naloxone did not affect prodynorphin-derived peptide concentrations. An increase of endogenous opioids was also observed after administration of the nonopiate clonidine, a compound which, like opiates, alters the activity of the myenteric plexus. It is suggested that feedback mechanisms in the myenteric plexus are responsible for the elevation of endogenous opioid peptides following exposure to exogenous opiates. Using a monoclonal antibody (3-E7), which recognizes virtually all endogenous opioid peptides, it was found that levels of higher molecular material were also increased upon opiate challenge. This suggests that a single dose of an exogenous opiate results in an increase in peptide synthesis.


Asunto(s)
Encefalinas/metabolismo , Plexo Mientérico/metabolismo , Narcóticos/farmacología , Precursores de Proteínas/metabolismo , Animales , Clonidina/farmacología , Dextrorfano/farmacología , Relación Dosis-Respuesta a Droga , Endorfinas/metabolismo , Íleon/efectos de los fármacos , Levorfanol/farmacología , Masculino , Ratones , Plexo Mientérico/efectos de los fármacos , Antagonistas de Narcóticos , Péptidos/metabolismo
19.
Open Forum Infect Dis ; 1(2): ofu040, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25734114

RESUMEN

BACKGROUND: The factors that contribute to increasing obesity rates in human immunodeficiency virus (HIV)-positive persons and to body mass index (BMI) increase that typically occurs after starting antiretroviral therapy (ART) are incompletely characterized. METHODS: We describe BMI trends in the entire Swiss HIV Cohort Study (SHCS) population and investigate the effects of demographics, HIV-related factors, and ART on BMI change in participants with data available before and 4 years after first starting ART. RESULTS: In the SHCS, overweight/obesity prevalence increased from 13% in 1990 (n = 1641) to 38% in 2012 (n = 8150). In the participants starting ART (n = 1601), mean BMI increase was 0.92 kg/m(2) per year (95% confidence interval, .83-1.0) during year 0-1 and 0.31 kg/m(2) per year (0.29-0.34) during years 1-4. In multivariable analyses, annualized BMI change during year 0-1 was associated with older age (0.15 [0.06-0.24] kg/m(2)) and CD4 nadir <199 cells/µL compared to nadir >350 (P < .001). Annualized BMI change during years 1-4 was associated with CD4 nadir <100 cells/µL compared to nadir >350 (P = .001) and black compared to white ethnicity (0.28 [0.16-0.37] kg/m(2)). Individual ART combinations differed little in their contribution to BMI change. CONCLUSIONS: Increasing obesity rates in the SHCS over time occurred at the same time as aging of the SHCS population, demographic changes, earlier ART start, and increasingly widespread ART coverage. Body mass index increase after ART start was typically biphasic, the BMI increase in year 0-1 being as large as the increase in years 1-4 combined. The effect of ART regimen on BMI change was limited.

20.
Praxis (Bern 1994) ; 100(1): 29-35, 2011 Jan 05.
Artículo en Alemán | MEDLINE | ID: mdl-21210358

RESUMEN

The human immunodeficiency virus type 1 (HIV-1) is the cause of a devastating pandemic. HIV-1 infection leads to the disease AIDS (acquired immunodeficiency syndrome) after several years of clinical latency defined by the occurrence of opportunistic infections. The immune system of the patient is not capable of controlling the virus, not to mention to eliminate the virus. Nowadays, the antiretroviral therapy is very efficient; however, eradication of HIV-1 is currently not feasible. Countless efforts to develop an effective vaccine failed so far. One common cause for development of drug resistance during antiretroviral therapy and these fallibilities of the immune system and vaccine candidates is the rapid adaptability of HIV-1 and the associated high diversity of circulating virus variants world wide and within each patient.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/virología , Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral/genética , Evolución Molecular , Variación Genética/genética , Infecciones por VIH/virología , VIH-1/genética , Vacunas contra el SIDA/inmunología , Vacunas contra el SIDA/uso terapéutico , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , VIH-1/inmunología , Humanos , Mutación/genética , Replicación Viral/genética
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