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1.
Trop Med Int Health ; 24(5): 571-585, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30843638

RESUMEN

OBJECTIVES: Northern Tanzania experiences significant malaria-related morbidity and mortality, but accurate data are scarce. We update the data on patterns of low-grade Plasmodium falciparum malaria infection among children in northern Tanzania. METHODS: Plasmodium falciparum malaria prevalence (pfPR) was assessed in a representative sample of 819 children enrolled in 94 villages in northern Tanzania between October 2015 and August 2016, using a complex survey design. Individual- and household-level risk factors for pfPR were elicited using structured questionnaires. pfPR was assessed using rapid diagnostic tests (RDTs) and thick film microscopy (TFM). Associations with pfPR, based on RDT, were assessed using adjusted odds ratios (aOR) and confidence intervals (CI) from weighted survey logistic regression models. RESULTS: Plasmodium falciparum malaria prevalence (pfPR) was 39.5% (95% CI: 31.5, 47.5) by RDT and 33.4% (26.0, 40.6) by TFM. pfPR by RDT was inversely associated with higher-education parents, especially mothers (5-7 years of education: aOR 0.55; 95% CI: 0.31, 0.96, senior secondary education: aOR 0.10; 95% CI: 0.02, 0.55), living in a house near the main road (aOR 0.34; 95% CI: 0.15, 0.76), in a larger household (two rooms: aOR 0.40; 95% CI: 0.21, 0.79, more than two rooms OR 0.35; 95% CI: 0.20, 0.62). Keeping a dog near or inside the house was positively associated with pfPR (aOR 2.01; 95% CI: 1.26, 3.21). pfPR was not associated with bed-net use or indoor residual spraying. CONCLUSIONS: Nearly 40% of children in northern Tanzania had low-grade malaria antigenaemia. Higher parental education and household metrics but not mosquito bed-net use were inversely associated with pfPR.


OBJECTIFS: La Tanzanie connaît une morbidité et une mortalité importantes liées au paludisme, mais les données précises sont rares. Nous mettons à jour les données sur les profils en matière d'infection par le paludisme à Plasmodium falciparum de faible grade chez les enfants dans le nord de la Tanzanie. MÉTHODES: La prévalence du paludisme à P. falciparum (pfPR) a été évaluée sur un échantillon représentatif de 819 enfants inscrits dans 94 villages dans le nord de la Tanzanie entre octobre 2015 et août 2016, à l'aide d'un plan d'enquête complexe. Des facteurs de risque de pfPR au niveau individuel et au niveau du ménage ont été déterminés à l'aide de questionnaires structurés. La pfPR a été évaluée à l'aide de tests de diagnostic rapides (TDR) et de microscopie à film épais (TFM). Les associations avec la pfPR, sur la base des TDR, ont été évaluées à l'aide des rapports de cotes ajustés (aOR) et des intervalles de confiance (IC) de modèles de régression logistique de surveillances pondérées. RÉSULTATS: La pfPR était de 39,5% (IC95%: 31,5-47,5) avec les TDR et de 33,4% (26,0-40,6) avec la TFM. La pfPR par les TDR était inversement associée aux parents avec un niveau d'éducation plus élevé, en particulier les mères (5-7 ans d'études: aOR: 0,55; IC95%: 0,31-0,96, enseignement secondaire supérieur: aOR: 0,10; IC95%: 0,02-0,55), vivre dans une maison proche de la route principale (aOR: 0,34; IC95%: 0,15-0,76), dans un ménage plus grand (2 chambres: aOR: 0,40; IC95%: 0,21-0,79, plus de 2 pièces aOR: 0,35; IC95%: 0,20-0,62). Garder un chien près ou à l'intérieur de la maison était positivement associé à la pfPR (aOR: 2,01; IC95%: 1,26-3,21). La pfPR n'était pas associée à l'utilisation de moustiquaire ou à la pulvérisation de résidus à l'intérieur. CONCLUSIONS: Près de 40% des enfants dans nord de la Tanzanie présentaient une antigénémie paludéenne de faible grade. Un niveau d'éducation parentale plus élevé et les indicateurs du ménage, mais pas l'utilisation de moustiquaires, étaient inversement associés à la pfPR.


Asunto(s)
Malaria Falciparum/etiología , Plasmodium falciparum , Adolescente , Animales , Antígenos , Niño , Preescolar , Estudios Transversales , Perros , Escolaridad , Composición Familiar , Femenino , Vivienda , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Masculino , Oportunidad Relativa , Mascotas , Prevalencia , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tanzanía/epidemiología
2.
Genes Immun ; 15(4): 241-6, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24622687

RESUMEN

Hepatitis C virus (HCV) infects an estimated 3% of the global population with the majority of individuals (75-85%) failing to clear the virus without treatment, leading to chronic liver disease. Individuals of African descent have lower rates of clearance compared with individuals of European descent and this is not fully explained by social and environmental factors. This suggests that differences in genetic background may contribute to this difference in clinical outcome following HCV infection. Using 473 individuals and 792,721 single-nucleotide polymorphisms (SNPs) from a genome-wide association study (GWAS), we estimated local African ancestry across the genome. Using admixture mapping and logistic regression, we identified two regions of interest associated with spontaneous clearance of HCV (15q24, 20p12). A genome-wide significant variant was identified on chromosome 15 at the imputed SNP, rs55817928 (P=6.18 × 10(-8)) between the genes SCAPER and RCN. Each additional copy of the African ancestral C allele is associated with 2.4 times the odds of spontaneous clearance. Conditional analysis using this SNP in the logistic regression model explained one-third of the local ancestry association. Additionally, signals of selection in this area suggest positive selection due to some ancestral pathogen or environmental pressure in African, but not in European populations.


Asunto(s)
Población Negra/genética , Estudio de Asociación del Genoma Completo , Hepatitis C Crónica/genética , Polimorfismo de Nucleótido Simple , Remisión Espontánea , Alelos , Proteínas Portadoras/genética , Cromosomas Humanos Par 15/genética , Cromosomas Humanos Par 20/genética , Femenino , Hepatitis C Crónica/etnología , Humanos , Masculino
3.
Br J Cancer ; 108(5): 1163-7, 2013 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-23443674

RESUMEN

BACKGROUND: Adolescent/young adult Hodgkin lymphoma (AYAHL) survivors report fewer exposures to infections during childhood compared with controls, and they have functional lymphocyte aberrations. The gut microbiota plays a central role in immunity. METHODS: We investigated whether fecal microbial diversity differed between 13 AYAHL survivors and their unaffected co-twin controls. Pyrosequencing of fecal bacterial 16S rRNA amplicons yielded 252 943 edited reads that were assigned to species-level operational taxonomic units (OTUs) and standardised for sequencing depth by random sampling. Microbial diversity was compared within vs between twin pairs and by case-control status. RESULTS: The number of unique OTUs was more similar within twin pairs compared with randomly paired participants (P=0.0004). The AYAHL cases had fewer unique OTUs compared with their co-twin controls (338 vs 369, P=0.015); this difference was not significant (169 vs 183, P=0.10) when restricted to abundant OTUs. CONCLUSION: In this small study, AYAHL survivors appear to have a deficit of rare gut microbes. Further work is needed to determine if reduced microbial diversity is a consequence of the disease, its treatment, or a particularly hygienic environment.


Asunto(s)
Bacterias/aislamiento & purificación , Heces/microbiología , Enfermedad de Hodgkin/microbiología , Adolescente , Adulto , Bacterias/genética , Humanos , Masculino , Metagenoma , Sobrevivientes , Adulto Joven
4.
Br J Cancer ; 104(3): 433-6, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21245864

RESUMEN

BACKGROUND: Immune perturbation likely affects the development of Kaposi sarcoma (KS) among people infected with the KS-associated herpesvirus (KSHV). We tested whether KSHV-seropositive individuals or cases of classic KS (cKS), which typically originates in the leg, had differing delayed-type hypersensitivity (DTH) in the forearm or leg. METHODS: Mantoux DTH with three antigens (Candida, tetanus, PPD) was performed on the forearm and leg of 15 cKS cases, 14 KSHV-positives without KS, and 15 KSHV-negative controls. The diameters of induration responses were compared by group and body site. RESULTS: Leg DTH was greater than forearm DTH among controls (mean difference 5.6 mm, P=0.0004), whereas this was not observed in cKS cases (-2.2 mm, P=0.32) or KSHV-positives (0.5 mm, P=0.56). Leg-minus-forearm DTH difference was greater in controls compared with cKS cases (P=0.004) and KSHV-positives (P=0.002). Leg-plus-forearm DTH was similar in controls (mean 28.2 mm) and cKS cases (24.5 mm, P=0.60), but it was reduced in KSHV-positives (11.8 mm, P=0.02), particularly in the leg (P=0.004) and marginally in the forearm (P=0.07). CONCLUSION: KS cases had weaker DTH only in the leg, whereas both body sites appeared weaker in KSHV-positives without KS. Both systemic and regional immune alterations may influence the development of this malignancy.


Asunto(s)
Herpesvirus Humano 8/inmunología , Hipersensibilidad Tardía/inmunología , Sarcoma de Kaposi/inmunología , Anciano , Femenino , Antebrazo , Humanos , Pierna , Masculino
5.
J Viral Hepat ; 18(3): 161-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20337924

RESUMEN

Hepatitis C virus (HCV) treatment failure and disease progression are more likely with high HCV-RNA load. Correlates of high HCV-RNA load in individuals with haemophilia are largely unknown. Among 1266 interferon naïve HCV-infected individuals with haemophilia, we compared those with high (> 2 x 106 HCV-RNA copies/mL) to lower viral load, overall and stratifying on HIV co-infection status using logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI). Overall, high HCV load was independently associated with longer duration of HCV infection (P(trend)=0.0001), body mass index ≥ 25 kg/m² (OR=1.4, 95% CI=1.1-1.9), and HIV co-infection (OR=1.4, 95% CI=1.0-1.8). Among 795 HIV-negative participants, high HCV-RNA load was associated with older age at HCV acquisition (OR=1.9 for > 15 years vs ≤ 2 years, P(trend)=0.008), and lower AST/platelet ratio (P(trend)=0.01), in addition to longer duration of HCV infection (P(trend)=0.0008), and body mass index ≥ 25 kg/m² (OR=1.6, P=0.005). Among 471 HIV-positive individuals, anti-retroviral therapy (ART) was the only variable associated with high HCV-RNA load (OR=1.8, CI=1.1-2.9 for combination ART; OR=1.8, CI=0.9-3.4, for other ART vs no treatment). High HCV-RNA load with haemophilia is more likely with longer duration of infection, older age at infection, higher body mass index, and antiretroviral therapy. These findings may help identify individuals at increased risk of HCV treatment failure and progression to end-stage liver disease.


Asunto(s)
Infecciones por VIH/virología , VIH/aislamiento & purificación , Hemofilia A/virología , Hepacivirus/genética , Hepatitis C/virología , ARN Viral/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Infecciones por VIH/sangre , Infecciones por VIH/tratamiento farmacológico , Hemofilia A/sangre , Hepatitis C/sangre , Humanos , Pruebas de Función Hepática , Modelos Logísticos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Carga Viral , Viremia/sangre , Viremia/virología , Adulto Joven
6.
Haemophilia ; 17(4): 641-9, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21362111

RESUMEN

Several genes that modify risk of factor VIII (FVIII) inhibitors in haemophilia A patients have been identified. Aside from the underlying mutations that cause haemophilia A, inhibitor risk appears to be modified by polymorphisms in various cytokines and immunomodulators including IL10, TNFα and CTLA4. HLA haplotypes have not been strong determinants of inhibitor risk. We sought to confirm previous observations on FVIII inhibitor risk-modifying genes and to test new candidate genes encoding various otherTH1/TH2 cytokines. We also sought to determine whether normal FVIII gene polymorphisms affect inhibitor risk in caucasians. We studied 915 caucasian, severe haemophilia A patients (282 inhibitor cases and 633 non-inhibitor controls). Genes were analysed using 368 tagging single nucleotide polymorphisms starting 20 kb 5' and ending 10 kb 3' of each gene's coding sequence; four other polymorphisms (factor V Leiden & prothrombin 20210 polymorphisms and two in HFE) were also evaluated. Haplotypes that increased inhibitor risk were found in IL10 (OR = 1.33, P = 0.04), IL12 (OR = 1.31, P = 0.04) and IL1α (OR = 2.16, P = 0.034). Protective haplotypes were seen in IL2 (OR = .69, P = 0.008) and IL1ß (OR = 0.75, P = 0.02). One rare haplotype in the FVIII gene increased the risk of inhibitor development by nearly fourfold (OR = 3.8, P = 0.004). We replicate previous findings for IL10; identify new associations with IL1, IL2 and IL12; and identify a rare FVIII haplotype in caucasians that is associated with increased inhibitor risk.


Asunto(s)
Inhibidores de Factor de Coagulación Sanguínea/genética , Haplotipos/genética , Hemofilia A/genética , Hemofilia A/inmunología , Interleucinas/genética , Adolescente , Adulto , Estudios de Casos y Controles , Genotipo , Humanos , Polimorfismo Genético/genética , Adulto Joven
7.
Nat Med ; 2(4): 405-11, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8597949

RESUMEN

Major histocompatibility complex (MHC) genes (HLA in humans) regulate the immune response to foreign antigens. Molecular and serologic techniques were used to identify products of HLA class I, class II and transporter (TAP) genes (also part of the MHC) in homosexual seroconverters to human immunodeficiency virus type 1 (HIV-1). Comprehensive statistical analysis produced an HLA profile that predicted time from HIV-1 infection to the onset of AIDS. The profile was developed in a cohort of 139 men and evaluated in a second unrelated cohort of 102 men. In the evaluation cohort, the profile discriminated a sixfold difference between groups with the shortest and longest times to AIDS (P = 0.001). These findings support current theory about control of antigen processing by HLA genes and have implications for immunopathogenesis of HIV-1 and other infections.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Infecciones por VIH/genética , VIH-1/aislamiento & purificación , Complejo Mayor de Histocompatibilidad/genética , Estudios de Cohortes , Ligamiento Genético , Infecciones por VIH/inmunología , Infecciones por VIH/mortalidad , Antígenos de Histocompatibilidad Clase I/análisis , Antígenos de Histocompatibilidad Clase II/análisis , Humanos , Masculino , Análisis de Supervivencia
8.
J Viral Hepat ; 17(2): 115-22, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19874478

RESUMEN

The main objectives of this study were to define the occurrence and levels of hepatitis B virus (HBV) DNA in asymptomatic HBV carriers, cirrhosis patients and hepatocellular carcinoma (HCC) cases from The Gambia, and to evaluate the risk for cirrhosis or HCC associated with HBV viremia. We used sensitive real-time quantitative PCR assays to measure HBV DNA in samples from a case-control study consisting of 60 asymptomatic HBV carriers, 53 cirrhotic patients and 129 HCC cases. Logistic regression was used to estimate the risks of cirrhosis and HCC associated with HBV-DNA levels and HBV e antigenemia (HBeAg) detection (a surrogate marker for viral replication). Detectable HBV viremia and HBeAg positivity were both significantly associated with cirrhosis (increasing risk by fourfold and 11-fold respectively) and with HCC (increasing risk by sixfold and threefold respectively). HBV-DNA levels were significantly higher in both HCC cases and cirrhotic patients compared to asymptomatic carriers (P < 0.01 for both). High-level HBV DNA (>10,000 copies/mL) was strongly associated with both HCC and cirrhosis (17- and 39-fold increased risk). Lower level HBV viremia (200-10,000 copies/mL) conferred a significant risk of HCC, although the association with cirrhosis was not significant. In conclusion, we find that high HBV-DNA levels are strongly associated with the serious sequelae of HBV infection, independent of HBeAg status. While risk for cirrhosis and for HCC notably increases at HBV-DNA levels >or=10,000 copies/mL, low-level viremia was also associated with significant risk for HCC.


Asunto(s)
Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/virología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/complicaciones , Cirrosis Hepática/epidemiología , Cirrosis Hepática/virología , Carga Viral , Adulto , Portador Sano/virología , ADN Viral/sangre , Femenino , Gambia/epidemiología , Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
9.
Genes Immun ; 10(4): 309-22, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19295541

RESUMEN

Interleukin-10 (IL-10) is a pleiotropic cytokine with both immunosuppressive and immunostimulatory functions. Its roles in infections and autoimmunity may have resulted in selective pressures on polymorphisms within the gene, leading to genomic coexistence of several semi-conserved haplotypes involved with diverse pathogen interactions during genomic evolution. Previous studies focused either exclusively on promoter haplotypes or on individual SNPs. We genotyped 21 single nucleotide polymorphisms in the human IL10 gene and examined this variation compared to other mammalian species sequences. Haplotype heterogeneity in human populations is centered around 'classic' 'proximal' promoter polymorphisms: -592, -819 and -1082. High-producing GCC haplotypes are by far the most numerous and diverse group, the intermediate IL-10 producing ACC-inclusive haplotypes seem to be related most closely to the ancestral haplotype, and the ATA-inclusive haplotypes cluster a separate branch with strong bootstrap support. We looked at associations of corresponding haplotypes with HIV progression. A haplotype trend regression confirmed that individuals carrying the low-producing ATA-inclusive haplotypes in European Americans progress to AIDS faster, and most likely explain the role of IL10. Our findings are consistent with the hypothesis that existing polymorphisms in this gene may reflect a balance of historic adaptive responses to autoimmune, infectious and other disease agents.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/genética , VIH-1 , Haplotipos/genética , Interleucina-10/genética , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Síndrome de Inmunodeficiencia Adquirida/virología , Animales , Estudios de Cohortes , Progresión de la Enfermedad , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Filogenia , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas
10.
Br J Cancer ; 100(5): 817-21, 2009 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-19190628

RESUMEN

Systemic autoimmune rheumatic diseases (SARDs) are chronic inflammatory and immuno-modulatory conditions that have been suggested to affect cancer risk. Using the Surveillance, Epidemiology and End Results-Medicare-linked database, women aged 67-99 years and diagnosed with incident breast cancer in 1993-2002 (n=84 778) were compared with an equal number of age-matched cancer-free female controls. Diagnoses of SARDs, including rheumatoid arthritis (RA, n=5238), systemic lupus erythematosus (SLE, n=340), Sjogren's syndrome (n=374), systemic sclerosis (n=128), and dermatomyositis (n=31), were determined from claim files for individuals from age 65 years to 1 year before selection. Associations of SARD diagnoses with breast cancer, overall and by oestrogen receptor (ER) expression, were assessed using odds ratio (OR) estimates from multivariable logistic regression models. The women diagnosed with RA were less likely to develop breast cancer (OR=0.87, 95% confidence interval (CI)=0.82-0.93). The risk reduction did not differ by tumour ER-status (OR=0.83, 95% CI=0.78-0.89 for ER-positive vs OR=0.91, 95% CI=0.81-1.04 for ER-negative, P for heterogeneity=0.14). The breast cancer risk was not associated with any of the other SARDs, except for a risk reduction of ER-negative cases (OR=0.49, 95% CI=0.26-0.93) among women with SLE. These findings suggest that systemic inflammation may affect breast epithelial neoplasia.


Asunto(s)
Anciano , Enfermedades Autoinmunes/epidemiología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Enfermedades Reumáticas/epidemiología , Anciano de 80 o más Años , Enfermedades Autoinmunes/complicaciones , Neoplasias de la Mama/metabolismo , Estudios de Casos y Controles , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Oportunidad Relativa , Población , Enfermedades Reumáticas/complicaciones , Factores de Riesgo , Clase Social
11.
Science ; 239(4835): 68-71, 1988 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-3336776

RESUMEN

In a prospective cohort study of 265 laboratory and affiliated workers, one individual with no recognized risk factors for human immunodeficiency virus type 1 (HIV-1) infection was HIV-1 seropositive at the time of entry into the study. Molecular analyses of two HIV-1 isolates derived in two independent laboratories from a blood sample from this worker showed that the isolates were indistinguishable from a genotypic form of HIV-1 present in the H9/HTLV-IIIB cell line. Exposure to this strain of virus most probably occurred during work with concentrated virus or culture fluids from virus-producing cell lines under standard Biosafety Level 3 containment. Although no specific incident leading to this infection has been identified, undetected skin contact with virus culture supernatant might have occurred. This worker was the only one found to be positive among the subgroup of 99 workers who shared a work environment involving exposure to concentrated virus. The incidence rate of 0.48 per 100 person-years exposure indicates that prolonged laboratory exposure to concentrated virus is associated with some risk of HIV-1 infection, which is comparable to the risk for health care workers experiencing a needle stick exposure. While none of the ten workers with parenteral exposure to HIV-1 in this cohort became infected, a worker in another laboratory did seroconvert following an injury with a potentially contaminated needle. Strict Biosafety Level 3 containment and practices should be followed when working with concentrated HIV-1 preparations, and further refinement of the procedures may be necessary.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/transmisión , Enfermedades Profesionales/etiología , Contención de Riesgos Biológicos , Seropositividad para VIH , Humanos , Laboratorios , Riesgo
12.
Science ; 231(4741): 992-5, 1986 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-3003917

RESUMEN

The incidence of the acquired immune deficiency syndrome (AIDS) among persons infected with human T-lymphotropic virus type III (HTLV-III) was evaluated prospectively among 725 persons who were at high risk of AIDS and had enrolled before October 1982 in cohort studies of homosexual men, parenteral drug users, and hemophiliacs. A total of 276 (38.1 percent) of the subjects were either HTLV-III seropositive at enrollment or developed HTLV-III antibodies subsequently. AIDS had developed in 28 (10.1 percent) of the seropositive subjects before August 1985. By actuarial survival calculations, the 3-year incidence of AIDS among all HTLV-III seropositive subjects was 34.2 percent in the cohort of homosexual men in Manhattan, New York, and 14.9 percent (range 8.0 to 17.2 percent) in the four other cohorts. Out of 117 subjects followed for a mean of 31 months after documented seroconversion, five (all hemophiliacs) developed AIDS 28 to 62 months after the estimated date of seroconversion, supporting the hypothesis that there is a long latency between acquisition of viral infection and the development of clinical AIDS. This long latency could account for the significantly higher AIDS incidence in the New York cohort compared with other cohorts if the virus entered the New York homosexual population before it entered the populations from which the other cohorts were drawn. However, risk of AIDS development in different populations may also depend on the presence of as yet unidentified cofactors.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/microbiología , Deltaretrovirus/metabolismo , Síndrome de Inmunodeficiencia Adquirida/fisiopatología , Síndrome de Inmunodeficiencia Adquirida/transmisión , Anticuerpos Antivirales/análisis , Dinamarca , Hemofilia A/microbiología , Homosexualidad , Humanos , Masculino , Ciudad de Nueva York , Riesgo , Sarcoma de Kaposi/microbiología , Factores de Tiempo , Estados Unidos
13.
Science ; 283(5408): 1748-52, 1999 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-10073943

RESUMEN

A selective advantage against infectious disease associated with increased heterozygosity at the human major histocompatibility complex [human leukocyte antigen (HLA) class I and class II] is believed to play a major role in maintaining the extraordinary allelic diversity of these genes. Maximum HLA heterozygosity of class I loci (A, B, and C) delayed acquired immunodeficiency syndrome (AIDS) onset among patients infected with human immunodeficiency virus-type 1 (HIV-1), whereas individuals who were homozygous for one or more loci progressed rapidly to AIDS and death. The HLA class I alleles B*35 and Cw*04 were consistently associated with rapid development of AIDS-defining conditions in Caucasians. The extended survival of 28 to 40 percent of HIV-1-infected Caucasian patients who avoided AIDS for ten or more years can be attributed to their being fully heterozygous at HLA class I loci, to their lacking the AIDS-associated alleles B*35 and Cw*04, or to both.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Genes MHC Clase I , Infecciones por VIH/inmunología , VIH-1 , Antígenos HLA-B/genética , Antígenos HLA-C/genética , Síndrome de Inmunodeficiencia Adquirida/genética , Adulto , Alelos , Presentación de Antígeno , Estudios de Cohortes , Progresión de la Enfermedad , Etnicidad , Predisposición Genética a la Enfermedad , Infecciones por VIH/genética , Sobrevivientes de VIH a Largo Plazo/estadística & datos numéricos , Antígenos HLA/genética , Heterocigoto , Homocigoto , Humanos , Células Asesinas Naturales/inmunología , Pérdida de Heterocigocidad , Modelos de Riesgos Proporcionales , Riesgo
14.
Science ; 273(5283): 1856-62, 1996 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-8791590

RESUMEN

The chemokine receptor 5 (CKR5) protein serves as a secondary receptor on CD4(+) T lymphocytes for certain strains of human immunodeficiency virus-type 1 (HIV-1). The CKR5 structural gene was mapped to human chromosome 3p21, and a 32-base pair deletion allele (CKR5Delta32) was identified that is present at a frequency of approximately0.10 in the Caucasian population of the United States. An examination of 1955 patients included among six well-characterized acquired immunodeficiency syndrome (AIDS) cohort studies revealed that 17 deletion homozygotes occurred exclusively among 612 exposed HIV-1 antibody-negative individuals (2.8 percent) and not at all in 1343 HIV-1-infected individuals. The frequency of CKR5 deletion heterozygotes was significantly elevated in groups of individuals that had survived HIV-1 infection for more than 10 years, and, in some risk groups, twice as frequent as their occurrence in rapid progressors to AIDS. Survival analysis clearly shows that disease progression is slower in CKR5 deletion heterozygotes than in individuals homozygous for the normal CKR5 gene. The CKR5Delta32 deletion may act as a recessive restriction gene against HIV-1 infection and may exert a dominant phenotype of delaying progression to AIDS among infected individuals.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/genética , Infecciones por VIH/genética , VIH-1 , Receptores de Citocinas/genética , Receptores del VIH/genética , Eliminación de Secuencia , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/fisiopatología , Síndrome de Inmunodeficiencia Adquirida/virología , Secuencia de Bases , Mapeo Cromosómico , Cromosomas Humanos Par 3 , Estudios de Cohortes , Progresión de la Enfermedad , Genes , Infecciones por VIH/inmunología , Infecciones por VIH/fisiopatología , Infecciones por VIH/virología , Hemofilia A/complicaciones , Heterocigoto , Homosexualidad Masculina , Homocigoto , Humanos , Inmunidad Innata/genética , Masculino , Datos de Secuencia Molecular , Receptores CCR5 , Factores de Riesgo , Análisis de Supervivencia
15.
Science ; 277(5328): 959-65, 1997 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-9252328

RESUMEN

The critical role of chemokine receptors (CCR5 and CXCR4) in human immunodeficiency virus-type 1 (HIV-1) infection and pathogenesis prompted a search for polymorphisms in other chemokine receptor genes that mediate HIV-1 disease progression. A mutation (CCR2-64I) within the first transmembrane region of the CCR2 chemokine and HIV-1 receptor gene is described that occurred at an allele frequency of 10 to 15 percent among Caucasians and African Americans. Genetic association analysis of five acquired immunodeficiency syndrome (AIDS) cohorts (3003 patients) revealed that although CCR2-64I exerts no influence on the incidence of HIV-1 infection, HIV-1-infected individuals carrying the CCR2-64I allele progressed to AIDS 2 to 4 years later than individuals homozygous for the common allele. Because CCR2-64I occurs invariably on a CCR5-+-bearing chromosomal haplotype, the independent effects of CCR5-Delta32 (which also delays AIDS onset) and CCR2-64I were determined. An estimated 38 to 45 percent of AIDS patients whose disease progresses rapidly (less than 3 years until onset of AIDS symptoms after HIV-1 exposure) can be attributed to their CCR2-+/+ or CCR5-+/+ genotype, whereas the survival of 28 to 29 percent of long-term survivors, who avoid AIDS for 16 years or more, can be explained by a mutant genotype for CCR2 or CCR5.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/genética , Infecciones por VIH/genética , VIH-1 , Mutación , Receptores de Quimiocina , Receptores de Citocinas/genética , Receptores del VIH/genética , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Síndrome de Inmunodeficiencia Adquirida/virología , Población Negra , Estudios de Cohortes , Progresión de la Enfermedad , Genotipo , Infecciones por VIH/inmunología , Infecciones por VIH/mortalidad , Infecciones por VIH/virología , Haplotipos , Heterocigoto , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple , Modelos de Riesgos Proporcionales , Receptores CCR2 , Receptores CCR5 , Análisis de Supervivencia , Población Blanca
16.
Science ; 279(5349): 389-93, 1998 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-9430590

RESUMEN

Stromal-derived factor (SDF-1) is the principal ligand for CXCR4, a coreceptor with CD4 for T lymphocyte cell line-tropic human immunodeficiency virus-type 1 (HIV-1). A common polymorphism, SDF1-3'A, was identified in an evolutionarily conserved segment of the 3' untranslated region of the SDF-1 structural gene transcript. In the homozygous state, SDF1-3'A/3'A delays the onset of acquired immunodeficiency syndrome (AIDS), according to a genetic association analysis of 2857 patients enrolled in five AIDS cohort studies. The recessive protective effect of SDF1-3'A was increasingly pronounced in individuals infected with HIV-1 for longer periods, was twice as strong as the dominant genetic restriction of AIDS conferred by CCR5 and CCR2 chemokine receptor variants in these populations, and was complementary with these mutations in delaying the onset of AIDS.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Quimiocinas CXC , Quimiocinas/genética , Infecciones por VIH/inmunología , VIH-1/fisiología , Síndrome de Inmunodeficiencia Adquirida/genética , Síndrome de Inmunodeficiencia Adquirida/virología , Adulto , Quimiocina CXCL12 , Quimiocinas/química , Quimiocinas/fisiología , Estudios de Cohortes , Progresión de la Enfermedad , Genes , Variación Genética , Genotipo , Infecciones por VIH/genética , Infecciones por VIH/virología , Heterocigoto , Humanos , Masculino , Datos de Secuencia Molecular , Oportunidad Relativa , Polimorfismo Genético , Grupos Raciales , Receptores CCR2 , Receptores CCR5/genética , Receptores CCR5/fisiología , Receptores CXCR4/metabolismo , Receptores de Quimiocina/genética , Receptores de Quimiocina/fisiología , Análisis de Supervivencia , Linfocitos T/virología
17.
Science ; 282(5395): 1907-11, 1998 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-9836644

RESUMEN

The CCR5 gene encodes a cell surface chemokine receptor molecule that serves as the principal coreceptor, with CD4, for macrophage-tropic (R5) strains of human immunodeficiency virus-type 1 (HIV-1). Genetic association analysis of five cohorts of people with acquired immunodeficiency syndrome (AIDS) revealed that infected individuals homozygous for a multisite haplotype of the CCR5 regulatory region containing the promoter allele, CCR5P1, progress to AIDS more rapidly than those with other CCR5 promoter genotypes, particularly in the early years after infection. Composite genetic epidemiologic analyses of genotypes bearing CCR5P1, CCR5-Delta32, CCR2-64I, and SDF1-3'A affirmed distinct regulatory influences for each gene on AIDS progression. An estimated 10 to 17 percent of patients who develop AIDS within 3.5 years of HIV-1 infection do so because they are homozygous for CCR5P1/P1, and 7 to 13 percent of all people carry this susceptible genotype. The cumulative and interactive influence of these AIDS restriction genes illustrates the multigenic nature of host factors limiting AIDS disease progression.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/fisiopatología , VIH-1 , Regiones Promotoras Genéticas , Receptores CCR5/genética , Receptores de Quimiocina , Receptores de Citocinas/genética , Síndrome de Inmunodeficiencia Adquirida/genética , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Alelos , Quimiocina CXCL12 , Quimiocinas CXC/genética , Estudios de Cohortes , Progresión de la Enfermedad , Genes Dominantes , Genes Recesivos , Predisposición Genética a la Enfermedad , Genotipo , Infecciones por VIH/genética , Infecciones por VIH/fisiopatología , Haplotipos , Heterocigoto , Homocigoto , Humanos , Modelos de Riesgos Proporcionales , Receptores CCR2 , Factores de Riesgo , Tasa de Supervivencia
18.
J Eur Acad Dermatol Venereol ; 22(9): 1101-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18384551

RESUMEN

BACKGROUND: Kaposi sarcoma (KS), a malignancy of dermal endothelial cells that is caused by human herpesvirus 8 (HHV8) infection, is sensitive to perturbations of immunity. Nicotine might be effective against KS because of its immunologic and vascular effects and because smoking is associated with a low risk of KS. OBJECTIVE AND STUDY DESIGN: We conducted a masked, randomized phase 2 clinical trial of transdermal nicotine and placebo patches to assess the safety and efficacy of nicotine against classic KS (cKS). SUBJECTS AND METHODS: Three cKS lesions, predominantly nodules, in each of 24 non-smoking patients were randomly assigned to 15 weeks continuous treatment with nicotine patch (escalated to 7 mg), identical masked placebo patch or no patch. Changes in lesion area and elevation from baseline through six follow-up visits, by direct measurement and by two independent readers using digital photographs of the lesions, were compared using non-parametric and regression methods. Changes in longitudinal levels of HHV8 antibodies and DNA in blood cells were similarly assessed. RESULTS: There were no systemic or serious adverse events, and compliance was good. One patient resumed smoking and discontinued patches, and two patients withdrew at week 12 for unrelated indications. Six (29%) of the remaining 21 suspended use of patches to relieve local skin irritation; four of these six completed the trial at reduced dose. Treatment assignment was not associated with significant or consistent changes in cKS lesion area or elevation, HHV8 viral load or antibodies. CONCLUSION: Transdermal nicotine and placebo patches caused no serious toxicities but had no demonstrable effect on nodular cKS lesions or HHV8 levels.


Asunto(s)
Nicotina/uso terapéutico , Sarcoma de Kaposi/tratamiento farmacológico , Administración Cutánea , Femenino , Herpesvirus Humano 8/aislamiento & purificación , Humanos , Masculino , Nicotina/administración & dosificación , Cooperación del Paciente , Placebos , Carga Viral
19.
J Clin Invest ; 89(6): 1923-30, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1601999

RESUMEN

The observation that approximately 70% of HIV-infected pregnant women do not transmit infection vertically suggests that antibody therapy may be effective in the prevention of transmission of HIV infection from mother to child. Currently, there is an incomplete understanding of the processes involved in vertical transmission of HIV infection. The elucidation of the serological basis of maternal immunity as it relates to protection from vertical transmission is the goal of this study. We have screened 20 maternal sera from HIV+ individuals of known vertical transmission status for reactivity with 31 peptides spanning the entire envelope glycoprotein of HIV-1. Of interest was reactivity to regions outside of the V3 loop of gp120. The findings have been examined in relationship to transmission status, as well as to in vitro anti-HIV-1 biological activity. Our results indicate that lack of vertical transmission is correlated with high viral neutralization activity, but not with antisyncytial activity nor with binding to the V3 peptides examined in this study. Also, the transmission group bound to fewer gp41 peptides when compared with the nontransmission group, suggesting that immune responses to gp41 may be important in preventing transmission. These findings may provide insights into the design of passive immunotherapies.


Asunto(s)
Proteína gp120 de Envoltorio del VIH/inmunología , Proteína gp41 de Envoltorio del VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/inmunología , Complicaciones Infecciosas del Embarazo/inmunología , Adulto , Secuencia de Aminoácidos , Estudios de Cohortes , Femenino , Células Gigantes/inmunología , Anticuerpos Anti-VIH/sangre , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/fisiología , Humanos , Recién Nacido , Datos de Secuencia Molecular , Pruebas de Neutralización , Fragmentos de Péptidos/inmunología , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Estudios Prospectivos , Células Tumorales Cultivadas
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