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1.
BMC Med ; 17(1): 174, 2019 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-31526369

RESUMEN

BACKGROUND: Different methodological choices such as inclusion/exclusion criteria and analytical models can yield different results and inferences when meta-analyses are performed. We explored the range of such differences, using several methodological choices for indirect comparison meta-analyses to compare nalmefene and naltrexone in the reduction of alcohol consumption as a case study. METHODS: All double-blind randomized controlled trials (RCTs) comparing nalmefene to naltrexone or one of these compounds to a placebo in the treatment of alcohol dependence or alcohol use disorders were considered. Two reviewers searched for published and unpublished studies in MEDLINE (August 2017), the Cochrane Library, Embase, and ClinicalTrials.gov and contacted pharmaceutical companies, the European Medicines Agency, and the Food and Drug Administration. The indirect comparison meta-analyses were performed according to different inclusion/exclusion criteria (based on medical condition, abstinence of patients before inclusion, gender, somatic and psychiatric comorbidity, psychological support, treatment administered and dose, treatment duration, outcome reported, publication status, and risk of bias) and different analytical models (fixed and random effects). The primary outcome was the vibration of effects (VoE), i.e. the range of different results of the indirect comparison between nalmefene and naltrexone. The presence of a "Janus effect" was investigated, i.e. whether the 1st and 99th percentiles in the distribution of effect sizes were in opposite directions. RESULTS: Nine nalmefene and 51 naltrexone RCTs were included. No study provided a direct comparison between the drugs. We performed 9216 meta-analyses for the indirect comparison with a median of 16 RCTs (interquartile range = 12-21) included in each meta-analysis. The standardized effect size was negative at the 1st percentile (- 0.29, favouring nalmefene) and positive at the 99th percentile (0.29, favouring naltrexone). A total of 7.1% (425/5961) of the meta-analyses with a negative effect size and 18.9% (616/3255) of those with a positive effect size were statistically significant (p < 0.05). CONCLUSIONS: The choice of inclusion/exclusion criteria and analytical models for meta-analysis can result in entirely opposite results. VoE evaluations could be performed when overlapping meta-analyses on the same topic yield contradictory result. TRIAL REGISTRATION: This study was registered on October 19, 2016, in the Open Science Framework (OSF, protocol available at https://osf.io/7bq4y/ ).


Asunto(s)
Metaanálisis como Asunto , Proyectos de Investigación , Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Alcoholismo/tratamiento farmacológico , Humanos , Naltrexona/análogos & derivados , Naltrexona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico
2.
Emerg Infect Dis ; 16(9): 1459-62, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20735933

RESUMEN

To determine human herpesvirus 8 (HHV-8) K1 genotypes in patients with Kaposi sarcoma (KS) from Peru, we characterized HHV-8 in 25 KS biopsy samples. Our findings of 8 A, 1 B, 14 C, and 2 E subtypes showed high HHV-8 diversity in these patients and association between E genotype and KS development.


Asunto(s)
Herpesvirus Humano 8/genética , Sarcoma de Kaposi/virología , Infecciones Oportunistas Relacionadas con el SIDA/patología , Infecciones Oportunistas Relacionadas con el SIDA/virología , ADN Viral/genética , Genes Virales , Genotipo , Herpesvirus Humano 8/clasificación , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Perú , Filogenia , Sarcoma de Kaposi/patología , Adulto Joven
3.
Addiction ; 113(2): 220-237, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28940866

RESUMEN

BACKGROUND AND AIMS: Pharmacologically controlled drinking in the treatment of alcohol dependence or alcohol use disorders (AUDs) is an emerging concept. Our objective was to explore the comparative effectiveness of drugs used in this indication. DESIGN: Systematic review with direct and network meta-analysis of double-blind randomized controlled trials (RCTs) assessing the efficacy of nalmefene, naltrexone, acamprosate, baclofen or topiramate in non-abstinent adults diagnosed with alcohol dependence or AUDs. Two independent reviewers selected published and unpublished studies on Medline, the Cochrane Library, Embase, ClinicalTrials.gov, contacted pharmaceutical companies, the European Medicines Agency and the Food and Drug Administration, and extracted data. SETTING: Thirty-two RCTs. PARTICIPANTS: A total of 6036 patients. MEASUREMENTS: The primary outcome was total alcohol consumption (TAC). Other consumption outcomes and health outcomes were considered as secondary outcomes. FINDINGS: No study provided direct comparisons between drugs. A risk of incomplete outcome data was identified in 26 studies (81%) and risk of selective outcome reporting in 17 (53%). Nalmefene [standardized mean difference (SMD) = -0.19, 95% confidence interval (CI) = -0.29, -0.10; I2  = 0%], baclofen (SMD = -1.00, 95% CI = -1.80, -0.19; one study) and topiramate (SMD = -0.77, 95% CI = -1.12, -0.42; I2  = 0%) showed superiority over placebo on TAC. No efficacy was observed for naltrexone or acamprosate. Similar results were observed for other consumption outcomes, except for baclofen (the favourable outcome on TAC was not reproduced). The number of withdrawals for safety reasons increased under nalmefene and naltrexone. No treatment demonstrated any harm reduction (no study was powered to explore health outcomes). Indirect comparisons suggested that topiramate was superior to nalmefene, naltrexone and acamprosate on consumption outcomes, but its safety profile is known to be poor. CONCLUSIONS: There is currently no high-grade evidence for pharmacological treatment to control drinking using nalmefene, naltrexone, acamprosate, baclofen or topiramate in patients with alcohol dependence or alcohol use disorder. Some treatments show low to medium efficacy in reducing drinking across a range of studies with a high risk of bias. None demonstrates any benefit on health outcomes.


Asunto(s)
Acamprosato/uso terapéutico , Alcoholismo/tratamiento farmacológico , Baclofeno/uso terapéutico , Naltrexona/análogos & derivados , Naltrexona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Topiramato/uso terapéutico , Metaanálisis en Red , Resultado del Tratamiento
4.
Haematologica ; 92(9): 1275-6, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17768127

RESUMEN

HHV-8-associated solid lymphomas which develop in extracavitary sites during the course of primary effusion lymphoma (PEL) could represent the relapse of original PEL tumors in different anatomical sites, or newly occurring distinct HHV-8-associated lymphomas, such as multicentric Castleman disease-related microlymphomas. HHV-8 episome clonality might help identify which event takes place.


Asunto(s)
Infecciones por Herpesviridae/complicaciones , Herpesvirus Humano 8/aislamiento & purificación , Linfoma Relacionado con SIDA/complicaciones , Linfoma/complicaciones , Recurrencia Local de Neoplasia/complicaciones , Derrame Pleural Maligno/complicaciones , Infecciones por Herpesviridae/virología , Herpesvirus Humano 8/genética , Humanos , Linfoma/virología , Linfoma Relacionado con SIDA/virología , Recurrencia Local de Neoplasia/virología , Derrame Pleural Maligno/virología
5.
Cancer Res ; 64(23): 8782-7, 2004 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-15574792

RESUMEN

Transmission of human herpesvirus 8 (HHV-8), the etiological agent of Kaposi's sarcoma, occurs mainly during childhood in endemic countries and, to a large extent, through intrafamilial contacts. To additionally investigate this familial transmission, and especially the role of plasma anti-HHV-8 antibody titers, we conducted a large survey in a village from Cameroon, Central Africa, including 92 families (608 individuals). Plasma samples were tested for specific IgG directed against HHV-8 lytic antigens by immunofluorescence assay, and titers were determined by 2-fold dilutions. Global HHV-8 seroprevalence was 60%, raising from 32% under 9 years up to a plateau of around 62% between 15 and 40 years. The familial correlation patterns in HHV-8 seropositive/seronegative status showed strong dependence from mother to child and between siblings. In contrast, no familial correlation in anti-HHV-8 antibody levels was observed among infected subjects. In particular, no relationship was observed between the anti-HHV-8 antibody titer of HHV-8 seropositive mothers and the proportion of their HHV-8 seropositive children. Furthermore, a random permutation study of the anti-HHV-8 antibody titers among HHV-8 infected subjects showed that the main risk factor for infection was the HHV-8 serologic status and not the antibody level. In addition, no correlation was found between anti-HHV-8 antibody levels and buffy coat HHV-8 viral loads in a subsample of 95 infected subjects. Overall, these results strongly suggest that, in this highly endemic population from Central Africa, HHV-8 transmission mainly occurs from mother to child and between siblings, and it is independent of plasma antibody levels of HHV-8 infected relatives.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Herpesviridae/transmisión , Herpesvirus Humano 8/inmunología , Adolescente , Adulto , África Central/epidemiología , Niño , Preescolar , Enfermedades Endémicas , Familia , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/inmunología , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Persona de Mediana Edad , Madres , Estudios Seroepidemiológicos
6.
Int J Biochem Cell Biol ; 37(12): 2457-65, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16188485

RESUMEN

Spindle cells represent the main cell type of the advanced final nodular stage of Kaposi's sarcoma lesions. Despite some clinical and epidemiological differences, the four Kaposi's sarcoma forms (classic, endemic, post-transplant and epidemic) display very similar histopathological features, with the proliferation of spindle cells (considered as the Kaposi's sarcoma tumor cells) associated with inflammation and neo-angiogenesis. Electron-microscopy and immuno-histochemistry studies have led to the consensus that the spindle cells originated from the endothelial lineage. However, only recently, studies that used specific lymphatic immunological markers (such as podoplanin) and molecular features (gene expression microarrays) strongly linked Kaposi's sarcoma spindle cells to the endothelium lymphatic cell lineage. Both hybridization and immuno-histochemistry techniques have demonstrated that human herpesvirus 8 also known as Kaposi's sarcoma associated herpesvirus was present in spindle cells at all stages of the disease (patch, plaque, nodule). Interestingly, while the human herpesvirus 8 latent genes are expressed in nearly all tumor spindle cells, only a small fraction of them expresses markers of viral lytic replication. Recent findings showing that nodular Kaposi's sarcoma lesions display all patterns of human herpesvirus 8 clonality support the model according to which this tumor begins as a polyclonal disease with a subsequent evolution to a mono/oligoclonal process involving infected spindle cells. Spindle cells appear to be the central masterpiece in KS tumorigenesis, however the exact respective role of each human herpesvirus 8 gene, in the initiation and the disease progression is still under investigation and the question of whether or not this tumor is a reactive process or a true malignant proliferation of spindle cells remains yet unclear.


Asunto(s)
Sarcoma de Kaposi/patología , Linaje de la Célula , Citocinas/biosíntesis , Células Endoteliales/patología , Células Endoteliales/virología , Herpesvirus Humano 8/patogenicidad , Humanos , Inmunohistoquímica , Inflamación/fisiopatología , Sarcoma de Kaposi/metabolismo
7.
Retrovirology ; 2: 30, 2005 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-15882466

RESUMEN

Human T-cell Leukemia virus type 1 (HTLV-1) and type 2 (HTLV-2) are pathogenic retroviruses that infect humans and cause severe hematological and neurological diseases. Both viruses have simian counterparts (STLV-1 and STLV-2). STLV-3 belongs to a third group of lymphotropic viruses which infect numerous African monkeys species. Among 240 Cameroonian plasma tested for the presence of HTLV-1 and/or HTLV-2 antibodies, 48 scored positive by immunofluorescence. Among those, 27 had indeterminate western-blot pattern. PCR amplification of pol and tax regions, using HTLV-1, -2 and STLV-3 highly conserved primers, demonstrated the presence of a new human retrovirus in one DNA sample. tax (180 bp) and pol (318 bp) phylogenetic analyses demonstrated the strong relationships between the novel human strain (Pyl43) and STLV-3 isolates from Cameroon. The virus, that we tentatively named HTLV-3, originated from a 62 years old Bakola Pygmy living in a remote settlement in the rain forest of Southern Cameroon. The plasma was reactive on MT2 cells but was negative on C19 cells. The HTLV 2.4 western-blot exhibited a strong reactivity to p19 and a faint one to MTA-1. On the INNO-LIA strip, it reacted faintly with the generic p19 (I/II), but strongly to the generic gp46 (I/II) and to the specific HTLV-2 gp46. The molecular relationships between Pyl43 and STLV-3 are thus not paralleled by the serological results, as most of the STLV-3 infected monkeys have an "HTLV-2 like" WB pattern. In the context of the multiple interspecies transmissions which occurred in the past, and led to the present-day distribution of the PTLV-1, it is thus very tempting to speculate that this newly discovered human retrovirus HTLV-3 might be widespread, at least in the African continent.


Asunto(s)
Deltaretrovirus/clasificación , Deltaretrovirus/aislamiento & purificación , Animales , Western Blotting , Camerún , Línea Celular , ADN Viral/sangre , Deltaretrovirus/genética , Infecciones por Deltaretrovirus/virología , Productos del Gen pol/genética , Productos del Gen tax/genética , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Virus Linfotrópico T Tipo 3 de los Primates , Análisis de Secuencia de ADN
8.
Pathology ; 37(4): 288-95, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16194827

RESUMEN

AIMS: The Maghreb region is considered to be an endemic area for classical Kaposi's sarcoma (KS) but the few published reports have focused on clinical descriptions. We report here the clinical, virological and pathological features of 26 KS cases, including 17 classic forms, eight epidemic forms and one case of post-transplant KS. METHODS: Evidence of human herpesvirus (HHV)-8 infection was detected by serology, immunohistochemistry and polymerase chain reaction. RESULTS: Antibodies directed against HHV-8 latent nuclear antigen (LNA-1/ORF73) were present in sera from all 26 KS cases and the ORF26 HHV-8 gene fragment was amplified from the tumour DNA of all patients. KS lesions that met the classical criteria for KS (spindle cells, positive endothelial markers) and were immunostained with the anti-LNA-1 marker, demonstrated typical granular intranuclear labelling of the spindle cells in all but one case of KS, in which very few spindle cells were present. Furthermore, whereas LNA-1 staining was largely confined to spindle cells in the late nodular stage, it was also observed in endothelial cells forming the walls of slit-like vessels in early patch-stage lesions. CONCLUSION: This study confirms that Morocco is an endemic area for classical KS, which remains the most frequent type of KS in this country, and emphasises the value of the LNA-1 marker for the early diagnosis of KS lesions.


Asunto(s)
Herpesvirus Humano 8/aislamiento & purificación , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Sarcoma de Kaposi/patología , Sarcoma de Kaposi/virología , Infecciones Oportunistas Relacionadas con el SIDA/patología , Infecciones Oportunistas Relacionadas con el SIDA/virología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , Antígenos Virales/metabolismo , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Marruecos/epidemiología , Reacción en Cadena de la Polimerasa , Sarcoma de Kaposi/epidemiología
10.
Emerg Infect Dis ; 13(11): 1745-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18217561

RESUMEN

We show human herpesvirus 8 with diverse molecular subtype D variants to be highly endemic among the Ni-Vanuatu population. Most K1 genes were nearly identical to Polynesian strains, although a few clustered with Australian or Taiwanese strains. These results suggest diverse origins of the Ni-Vanuatu population and raise questions about the ancient human population movements in Melanesia.


Asunto(s)
Enfermedades Endémicas , Infecciones por Herpesviridae/virología , Herpesvirus Humano 8/clasificación , Sarcoma de Kaposi/virología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , Niño , Preescolar , Femenino , Técnica del Anticuerpo Fluorescente/métodos , Variación Genética/genética , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/epidemiología , Herpesvirus Humano 8/genética , Humanos , Lactante , Masculino , Melanesia/epidemiología , Persona de Mediana Edad , Linaje , Filogenia , Sarcoma de Kaposi/sangre , Sarcoma de Kaposi/epidemiología , Proteínas Virales/genética
11.
J Infect Dis ; 196(4): 510-21, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17624835

RESUMEN

BACKGROUND: Melanesia is endemic for human T lymphotropic virus type 1 (HTLV-1) subtype C. In 2005, we identified 4 infected women from Ambae Island, Vanuatu. Subsequently, 4247 Ni-Vanuatu originating from 18 islands were enrolled to define HTLV-1 epidemiological determinants and to characterize the viral strains molecularly. METHODS: Plasma from 1074 males and 3173 females were screened for HTLV-1/2 antibodies by particle agglutination (PA) and an immunofluorescence assay (IFA). Positive and/or borderline samples were then tested by a Western blot (WB) confirmatory assay. DNAs were amplified to obtain a 522-bp env gene fragment. Phylogenetic and molecular-clock analyses were performed. RESULTS: Of 4247 samples, 762 were positive and/or borderline by IFA/PA, and 26 of them were confirmed to be HTLV-1 positive by WB. The overall HTLV-1 seroprevalence was 0.62%. Viral transmission was found within families of infected index case patients. A geographic heterogeneity of HTLV-1 seroprevalence was observed among the islands. All 41 of the new env sequences belonged to HTLV-1 subtype C. Phylogenetic and molecular-clock analyses suggested that Ni-Vanuatu and Solomon Islander strains emerged from a common ancestor ~10,000 years ago. CONCLUSION: The Vanuatu archipelago is endemic for HTLV-1 with a diversity of subtype C variants. These strains were probably introduced into Vanuatu during ancient migration of the original settlers a few thousand years ago.


Asunto(s)
Anticuerpos Anti-HTLV-I/sangre , Infecciones por HTLV-I/epidemiología , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 1 Humano/inmunología , Epidemiología Molecular , Adolescente , Adulto , Aglutinación , Evolución Biológica , Niño , Preescolar , Estudios Transversales , Femenino , Técnica del Anticuerpo Fluorescente , Productos del Gen env/genética , Variación Genética , Virus Linfotrópico T Tipo 1 Humano/clasificación , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Masculino , Melanesia/epidemiología , Persona de Mediana Edad , Linaje , Filogenia , Reacción en Cadena de la Polimerasa , Población Rural , Estudios Seroepidemiológicos , Especificidad de la Especie , Vanuatu/epidemiología
12.
J Natl Cancer Inst ; 99(14): 1086-94, 2007 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-17623796

RESUMEN

BACKGROUND: Kaposi sarcoma (KS) is a complex tumor of uncertain clonality. Studying the viral clonality of the human herpesvirus 8 (HHV-8) in KS to determine clonality of the tumors, a strategy that has been used previously with Epstein-Barr virus and its associated tumors, may elucidate whether multicentric (disseminated) KS lesions correspond to metastatic lesions or to expansions of independent clones. METHODS: A series of 139 KS biopsies (from skin, lymph node, or tonsil) was obtained from 98 patients, with 59 biopsies from 18 patients with disseminated multicentric KS skin lesions. The degree of spindle cell infiltration in biopsies was established by direct observation of hematoxylin-eosin-stained sections, and HHV-8 viral load was quantified by real-time polymerase chain reaction. To determine cellular clonality, the size heterogeneity of the HHV-8-fused terminal repeat (TR) region was determined by probing of electrophoresed restricted genomic DNA from KS biopsies for the HHV-8 TR sequence. RESULTS: HHV-8 clonality analysis was performed on the 62 samples for which sufficient DNA was obtained. Most samples corresponded to histologically nodular lesions with high spindle cell infiltration and high viral load. A clonal HHV-8 pattern was determined for 59 samples; 11 were found to be monoclonal and 48 to be oligoclonal. The informative samples that were from disseminated KS skin lesions (n = 26, from six patients) were either monoclonal or oligoclonal, and the size of HHV-8 episomes varied between these samples. CONCLUSION: Although some tumor KS lesions were monoclonal expansions of HHV-8-infected spindle cells, most advanced lesions were oligoclonal proliferations. Furthermore, individual KS disseminated tumor skin lesions were found to represent distinct expansions of HHV-8-infected spindle cells. Thus, our results suggest that KS lesions, especially in patients with advanced skin tumors, are reactive proliferations rather than true malignancies with metastatic dissemination.


Asunto(s)
Herpesvirus Humano 8/genética , Sarcoma de Kaposi/patología , Sarcoma de Kaposi/virología , Piel/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Células Clonales/patología , Células Clonales/virología , ADN Viral/análisis , ADN Viral/genética , Femenino , Herpesvirus Humano 8/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Carga Viral
13.
J Virol ; 80(19): 9876-88, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16973592

RESUMEN

We and others have recently uncovered the existence of human T-cell lymphotropic virus type 3 (HTLV-3), the third member of the HTLV family. We have now sequenced the full-length HTLV-3Pyl43 provirus. As expected, HTLV-3Pyl43 contains open reading frames corresponding to the gag, pol, env, tax, and rex genes. Interestingly, its long terminal repeat (LTR) includes only two Tax-responsive elements, as is the case for type 3 simian T-cell lymphotropic viruses (STLV-3). Phylogenetic analyses reveal that HTLV-3Pyl43 is closely related to central African STLV-3. Unexpectedly, the proximal pX region of HTLV-3Pyl43 lacks 366 bp compared to its STLV-3 counterpart. Because of this deletion, the previously described RorfII sequence is lacking. At the amino acid level, Tax3Pyl43 displays strong similarities with HTLV-1 Tax, including the sequence of a PDZ class I binding motif. In transient-transfection assays, Tax3Pyl43 activates the transcriptions from HTLV-3, HTLV-1, and HTLV-2 LTRs. Mutational analysis indicates that two functional domains (M22 and M47) important for transactivation through the CREB/ATF or NF-kappaB pathway are similar but not identical in Tax1 and Tax3Pyl43. We also show that Tax3Pyl43 transactivates the human interleukin-8 and Bcl-XL promoters through the induction of the NF-kappaB pathway. On the other hand, Tax3Pyl43 represses the transcriptional activity of the p53 tumor suppressor protein as well as the c-Myb promoter. Altogether, these results demonstrate that although HTLV-3 and HTLV-1 have only 60% identity, Tax3Pyl43 is functionally closely related to the transforming protein Tax1 and suggest that HTLV-3, like HTLV-1, might be pathogenic in vivo.


Asunto(s)
VIH/genética , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Línea Celular , Genoma Viral/genética , VIH/química , VIH/metabolismo , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Persona de Mediana Edad , Datos de Secuencia Molecular , Proteínas Proto-Oncogénicas c-myb/genética , Proteínas Proto-Oncogénicas c-myb/metabolismo , Alineación de Secuencia , Transactivadores/química , Transactivadores/genética , Transactivadores/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
14.
Virology ; 353(1): 121-32, 2006 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16793109

RESUMEN

The genetic variability of the human herpesvirus 8 (HHV-8) strains circulating in the populations living in the Maghreb region, an endemic area for HHV-8 and associated Kaposi's sarcoma, remains largely unknown. We have thus analyzed the genetic variation of the complete K1 gene of HHV-8 in a series of 35 viral strains, originating from 28 Moroccan patients with classic, AIDS-associated or iatrogenic Kaposi's sarcoma lesions. All but one of the 35 strains belonged to the large C molecular subtype. Furthermore, high genetic diversity within the C subtype was observed in the 35 sequenced HHV-8 K1 genes, with strains belonging to several and distinct subgroups highly supported from a phylogenetically viewpoint (e.g., C3, C7, C'' and C5). Considering these newly identified Moroccan viral strains in the context of 189 complete K1 genes, we were able to characterized, using the Simplot program, two main groups of recombinant chimeric K1 genes, either intertypic (C5) or intratypic (C7). In addition, the genetic characterization of the host maternal gene pool, through the analyses of mtDNA variation, did not provide evidence for any association between a particular human ethno-geographic background (i.e., North African vs. sub-Saharan African vs. West Eurasian linages) and any HHV-8 strain because both C' and C'' strains were randomly distributed among the different patients' population backgrounds.


Asunto(s)
Genes Virales , Epidemiología Molecular , Sarcoma de Kaposi/epidemiología , Sarcoma de Kaposi/virología , Proteínas Virales/genética , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , ADN Mitocondrial/genética , Femenino , Pool de Genes , Variación Genética , Humanos , Masculino , Persona de Mediana Edad , Marruecos/epidemiología , Filogenia , Polimorfismo Genético , Población/genética , Recombinación Genética , Análisis de Secuencia de ADN , Proteínas Virales/clasificación
15.
Eur J Pediatr ; 165(7): 453-7, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16602009

RESUMEN

INTRODUCTION: Kaposi's sarcoma (KS) is rare in childhood. It may be favored by acquired immune deficiencies, but the predisposing factors to KS in other children are unclear. DISCUSSION: KS has been reported in only two children and one adult with primary immunodeficiency. We report here a Tunisian child with a Wiskott-Aldrich syndrome who developed KS at the age of 14 months. CONCLUSION: This observation expands the spectrum of primary immunodeficiencies associated with KS in childhood.


Asunto(s)
Sarcoma de Kaposi/inmunología , Síndrome de Wiskott-Aldrich/inmunología , Terapia Combinada , Diagnóstico Diferencial , Humanos , Lactante , Masculino , Sarcoma de Kaposi/diagnóstico , Sarcoma de Kaposi/terapia , Síndrome de Wiskott-Aldrich/diagnóstico , Síndrome de Wiskott-Aldrich/terapia
16.
Int J Cancer ; 115(4): 511-8, 2005 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15700304

RESUMEN

Primary effusion lymphoma (PEL) is a rare lymphoma of B-cell origin, developed in serous cavities. PEL tumor cells are latently infected with Kaposi sarcoma-associated herpesvirus (KSHV) and in most cases co-infected with Epstein-Barr virus (EBV). In 15 primary PEL tumors including 10 EBV-positive cases, we analyzed the fused terminal repeat (TR) regions of KSHV episomes using pulsed-field gel electrophoresis and Southern blot. On the same genomic DNA samples, the cellular clonality was assessed by Southern blot and PCR detection of monoclonal immunoglobulin heavy chain (IGH) VDJ gene rearrangements, associated in the EBV-infected cases, with Southern blot analysis of the fused termini of EBV episomes. Monoclonal IGH gene rearrangements were detected in 13 tumors using Southern blot, in 11 cases using PCR, and in all cases considering both methods. EBV infection was monoclonal in all EBV-positive cases. However, only 5 PEL tumors were found to be monoclonally infected with KSHV. In the 10 other cases, we found a biclonal (2 bands; n = 4) or an oligoclonal pattern (3-6 bands; n = 6) of KSHV episomes. We hypothesized that the apparent discrepancy between viral and cellular clonalities in PEL might be due to several phenomena including complex mechanisms of genomic recircularization, insertion of duplicated sequences into the TR region and simultaneous infection of tumor cells with defective KSHV variants. KSHV infection of contaminating nontumoral cells, superinfection from lytically infected cells or viral integration events might also explain the oligoclonal pattern of KSHV infection. Several of these mechanisms, not mutually exclusive, might coexist in a single tumor.


Asunto(s)
Herpesvirus Humano 8/aislamiento & purificación , Linfoma de Células B/virología , Sarcoma de Kaposi/virología , Adulto , Anciano , Antígenos CD/sangre , Electroforesis en Gel de Campo Pulsado , Femenino , Herpesvirus Humano 8/genética , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Linfoma de Células B/inmunología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Mapeo Restrictivo , Sarcoma de Kaposi/inmunología
17.
J Clin Microbiol ; 43(9): 4840-3, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16145154

RESUMEN

Epidemic Kaposi's sarcoma (KS) is one of the most frequent types of cancer in several African countries; however, very few data are available on human herpesvirus 8 (HHV-8) markers in KS patients from Central Africa. In a series of 36 AIDS-KS cases from Central African Republic, we showed, using a real-time PCR quantitative assay, the high frequency (82%) of detectable HHV-8 DNA in peripheral blood mononuclear cells (PBMCs). We also found that the level of antibodies directed against lytic or latent HHV-8 antigens is not correlated to the amount of HHV-8 viral load in the PBMCs, and finally, we demonstrated a much higher viral load in tumoral skin lesions (6.07 log copies/mug DNA) than in unaffected skin (2.93 log copies/mug DNA) or in PBMCs (2.55 log copies/mug DNA).


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/virología , Anticuerpos Antivirales/sangre , ADN Viral/sangre , Herpesvirus Humano 8/aislamiento & purificación , Sarcoma de Kaposi/virología , Neoplasias Cutáneas/virología , Carga Viral , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Adolescente , Adulto , Antígenos Virales/inmunología , República Centroafricana , Niño , ADN Viral/análisis , Femenino , Infecciones por VIH , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/inmunología , Humanos , Leucocitos Mononucleares/virología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Sarcoma de Kaposi/inmunología , Piel/virología
18.
J Infect Dis ; 192(9): 1525-9, 2005 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-16206066

RESUMEN

We evaluated the presence of human herpesvirus 8 (HHV-8) infection among groups of Amerindians in French Guiana. The overall prevalence of antibodies against lytic HHV-8 antigens was 23.0% (180/781), increasing from 18.4% in children <6 years old to approximately 30% in older persons (>45 years). Seroprevalence was higher in Amerindians living in remote localities than it was in those living in the coastal region. Analysis of a 725-base pair fragment of the K1 gene amplified from DNA from a Wayampi Amerindian showed that the virus belonged to molecular subtype E, which has hitherto been found in only a few Amerindians in Brazil and Ecuador.


Asunto(s)
Enfermedades Endémicas , Infecciones por Herpesviridae/etnología , Infecciones por Herpesviridae/epidemiología , Herpesvirus Humano 8/clasificación , Herpesvirus Humano 8/aislamiento & purificación , Indígenas Norteamericanos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/inmunología , Niño , Preescolar , ADN Viral/genética , Guyana Francesa/epidemiología , Genes Virales , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/virología , Herpesvirus Humano 8/genética , Humanos , Lactante , Persona de Mediana Edad , Prevalencia , Proteínas Represoras/inmunología , Población Rural , Estudios Seroepidemiológicos , Proteínas Virales/genética , Proteínas Virales/inmunología
19.
Emerg Infect Dis ; 10(5): 899-902, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15200826

RESUMEN

We obtained 475 nucleotides of the DNA polymerase gene of a novel human herpesvirus 8 homolog sequence in a gibbon. The finding of this new gibbon virus, which clusters with a related chimpanzee virus in the rhadinovirus 2 genogroup, suggests the existence of a novel gamma-2-herpesvirus in humans.


Asunto(s)
Evolución Molecular , Infecciones por Herpesviridae/veterinaria , Hylobates/virología , Rhadinovirus/clasificación , Rhadinovirus/genética , Infecciones Tumorales por Virus/veterinaria , Animales , ADN Polimerasa Dirigida por ADN/genética , Infecciones por Herpesviridae/virología , Humanos , Datos de Secuencia Molecular , Rhadinovirus/aislamiento & purificación , Análisis de Secuencia de ADN , Infecciones Tumorales por Virus/virología
20.
J Med Virol ; 71(4): 548-56, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14556268

RESUMEN

We report the molecular characterization of 38 new Kaposi's sarcoma-associated herpesvirus (KSHV) strains from Russian patients with either classic (25 cases), epidemic/AIDS-associated (7 cases), or posttransplant/immunosuppressed patients (6 cases), or Kaposi's sarcoma (KS). While a complete sequence of the K1 gene (870 bp) was obtained from 30 strains, only partial sequences of the hypervariable regions VR1 (372 bp) and/or VR2 (381 bp) of the K1 gene were obtained from eight strains of KS paraffin blocks. Sequence comparison and phylogenetic studies indicate that the novel KSHV strains belong to either the A subtype (28 cases) or the C subtype (10 cases). Within the 28 strains of A subtype, 24 (86%) belong to the large A' subgroup, mostly A1 and A1' clades, and 4 belong to the A" subgroup, mostly A3 clade. Within the 10 strains of subtype C, 4 were of C' subgroup, and 6 of the C". Some molecular variants of subtype A' were observed, with 3 strains exhibiting an insertion of a single amino acid at the position 65 and 2 strains (both from AIDS-KS) with an unique deletion of 17 amino acids in the VR2 region. Polymerase chain reaction-based subtyping of the K14.1 genomic region indicated that most (23/32) of the novel strains belonged to the P subtype. The results indicate that despite a wide genetic diversity of A and C K1 subtypes of KSHV strains present in Russia, most are closely related and belong to the A1 or A1' molecular clades suggesting a common origin. This study also expands the data regarding the absence of any correlation between a K1 molecular subtype and a specific KS type (classic, epidemic, or posttransplant), as well as between the K1 and K14.1 molecular subtypes.


Asunto(s)
Herpesvirus Humano 8/genética , Herpesvirus Humano 8/aislamiento & purificación , Sarcoma de Kaposi/virología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , ADN Viral/genética , Evolución Molecular , Femenino , Genes Virales , Variación Genética , Herpesvirus Humano 8/clasificación , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Federación de Rusia/epidemiología , Sarcoma de Kaposi/epidemiología , Sarcoma de Kaposi/etiología , Inmunología del Trasplante
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