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1.
Mol Phylogenet Evol ; 65(2): 523-34, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22828178

RESUMO

We investigated the evolution of the Asian francolins, five little known species in the genus Francolinus (Phasianidae). Evolutionary affinities of two of these species, F. gularis (swamp francolin) and F. pondicerianus (grey francolin), has long remained unclear. In contrast, the other three species, F. pintadeanus (Chinese francolin), F. pictus (painted francolin) and F. francolinus (black francolin) have been cast among the "spotted francolins" on a morphological and ecological basis. Previous molecular DNA investigations including Asian francolins mostly relied upon partial gene sequencing of one specimen per species (no more than three species and with the exclusion of F. pictus). Therefore, fundamental questions do persist. What relationship exists among the spotted and the other Asian francolins? What is the geographic origin of the black francolin, the species with the largest distribution range? How did the geological history influence the diversification of francolins across Asia? We sequenced the entire Control Region of the mitochondrial DNA in 228 samples of all five Asian francolin species, which were collected in 16 countries (from East Europe to East Asia). We constructed a molecular phylogeny according to four different procedures. We showed the monophyly of each of the Asian francolins and the spotted group, while that of the entire Asian group was presumed according to a biogeographical model we proposed. The splitting of the genus Francolinus occurred ~17.4 Ma (95% HPD: 13.4-22.1) while the spotted francolins diverged ~10.5 Ma (7.0-14.9). We resolved the most recent common ancestor to painted and black francolin as being in the Indian sub-continent, thus suggesting a westwards adaptive radiation of the latter. In Pakistan, we identified F. f. asiae representatives in the Northern Areas and in the Sindh. The latter represents a relict population of Indian fauna within the Pakistani range of the Great Rann of Kachchh.


Assuntos
Evolução Molecular , Galliformes/classificação , Especiação Genética , Filogenia , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Galliformes/genética , Funções Verossimilhança , Filogeografia , Análise de Sequência de DNA
2.
J Chemother ; 23(1): 24-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21482490

RESUMO

The aim of this study was to assess the correlation between the estimated adherence of HIV-1 infected patients with antiretroviral (ARV) therapy failure and drug-resistant mutations. We studied 40 patients with virological and immunological ARV-therapy failure. In order to assess the adherence of patients we used the SERAD questionnaire. Genomic sequencing of the HIV-1 pol gene was performed. 100% adherence was reported by 27 patients (67.5%) (adherent patients). Multivariate analysis showed that only baseline and nadir CD4+ counts maintained a significant correlation with the adherence. For PR and NNRTI mutations, we did not find any difference between the two groups of patients. Baseline NRTI mutations were higher in adherent patients than in non-adherent patients (p<0.05). No differences were found between plasma mutations and PBMC mutations. The authors conclude that genotypic resistance mutations were found in the majority of patients with ARV-therapy failure despite a good self-reported adherence to therapy. Adequate adherence to therapy is not the only key factor in viral suppression.


Assuntos
Antirretrovirais/administração & dosagem , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/genética , Mutação , Cooperação do Paciente , Adulto , Contagem de Linfócito CD4/métodos , Farmacorresistência Viral , Feminino , Genes pol/efeitos dos fármacos , Genótipo , Infecções por HIV/sangue , Infecções por HIV/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Sequência de DNA , Inquéritos e Questionários , Falha de Tratamento
3.
Clin Exp Immunol ; 135(2): 280-5, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14738457

RESUMO

A discordant response to highly active antiretroviral therapy (HAART) occurs when CD4 T cell counts are stable or increased over time despite persistently detectable HIV-RNA levels. In order to identify immunological factors affecting discordant treatment responses, a total of 27 HIV-infected patients were studied: (a) 10 naive patients (mean CD4+ = 101.5 cells/microl; mean HIV-RNA = 4.8 log10 copies/ml); (b) seven responder patients (mean CD4+ = 908.9 cells/microl); and (c) 10 discordant patients (mean CD4+ = 396.1 cells/microl; mean HIV-RNA = 5.4 log10 copies/ml). Five healthy blood donors were included as HIV-seronegative controls. The following parameters were evaluated: interleukin (IL)-15 production by monocyte-derived dendritic cells (MDDC) after stimulation with lypopolysaccaride (LPS) and Candida albicans; recall and HIV-1-specific antigen lymphocyte proliferation (LP). Increased levels of IL-15 production by MDDC after stimulation with LPS and C. albicans were found both in discordant patients and responder patients. Conversely, a strong reduction of IL-15 levels was observed in naive patients. Discordant patients developed positive LP responses to C. albicans and HIV-1 p24. LP in response to C. albicans and HIV-1 p24 was also positive in responder patients. Decreased LP response was found in naive patients. In conclusion, HIV-infected patients with discordant viro-immunological responses to HAART present increased levels of IL-15 production by MDDC and enhanced recall and HIV-1-specific antigen LP responses, suggesting an improvement in indices of immune function.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Células Dendríticas/imunologia , Infecções por HIV/imunologia , Interleucina-15/biossíntese , Linfócitos T/imunologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Candida albicans/imunologia , Células Dendríticas/metabolismo , Feminino , Antígenos HIV/imunologia , Proteína do Núcleo p24 do HIV/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , HIV-1/imunologia , Humanos , Lipopolissacarídeos/imunologia , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , RNA Viral/análise
4.
HIV Clin Trials ; 2(2): 108-12, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11590518

RESUMO

UNLABELLED: Interleukin (IL)-7 is a critical cytokine regulating T-lymphocyte development, regeneration, and function. PURPOSE: This study analyzes the endogenous IL-7 production in HIV-infected patients receiving highly active antiretroviral treatment (HAART). METHOD: Plasma levels of IL-7 were measured by enzyme-linked immunosorbent assay (ELISA) in 11 patients with untreated advanced HIV disease, in 8 patients who successfully responded to HAART, and in 9 individuals with virological and immunological treatment failure. RESULTS: We found that in the patients with advanced HIV disease and no treatment IL-7 concentrations were elevated and were inversely related to both CD4 + and CD8 + T-cell counts. When IL-7 was assessed in treated patients, this cytokine was below the detection limit of the assay in all participants who responded to HAART. On the contrary, patients with evidence of HAART failure had increased concentrations of IL-7 that were comparable to those found in the untreated group with progressive disease. CONCLUSION: These data suggest that IL-7 may play a role in the immune reconstitution of T-cells during HIV infection, especially in the context of potent antiretroviral treatments.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Interleucina-7/sangue , Adulto , Contagem de Linfócito CD4 , Linfócitos T CD8-Positivos , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue
5.
J Infect ; 42(4): 267-71, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11545570

RESUMO

OBJECTIVES: To determine the clinical features, sites of involvement, bacteriological findings, and outcome of infective endocarditis (IE) in patients with HIV infection. PATIENTS AND METHODS: All patients with diagnosis of IE admitted to 54 infectious disease centres in Italy over a 15-year period (1984-1999) were reviewed, and 895 cases fulfilled the Duke criteria for definite diagnosis of IE. Data were collected with regard to the clinical, laboratory, and demographic characteristics of patients, as well as results of blood cultures and data on clinical outcome. RESULTS: There were 108 episodes of IE in 105 HIV-infected patients. The mean age of patients was 30.1 years, and the commonest predisposing condition was intravenous drug use (94.3%). Staphylococci were the predominant organisms (60.2%), and the tricuspid valve was the most frequently involved site of infection (51.9%). Left-sided heart involvement (45.4%) and multivalvular involvement (17.6%) were also frequently observed. The greater frequency of S. aureus affecting the tricuspid valve vs. other valves was statistically significant (P<0.001). Six patients (5.9%) underwent surgery, and one (16.7%) of them died. Ninety-five (94.1%) patients were treated medically, and 17 (17.9%) of them died. Overall mortality rate was 17.8%. Any left-sided heart involvement was predictive of an increased risk of death if compared with any right-sided heart involvement (P< 0.004). The mortality rate among HIV-infected patients was higher in those with CD4 cell counts below 200/mm(3). CONCLUSIONS: IE in HIV-infected patients, for the most part intravenous drug users, is more commonly localized to the right side of the heart; however, mixed or left-side valvular infections are frequent. Severe immunosuppression and left-side valvular involvement are associated with a greater risk for mortality.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/microbiologia , Adulto , Contagem de Linfócito CD4 , Candida albicans/isolamento & purificação , Diagnóstico Diferencial , Endocardite/diagnóstico , Endocardite/microbiologia , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Staphylococcus aureus/isolamento & purificação , Streptococcus/isolamento & purificação
7.
J Infect Dis ; 182(5): 1536-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11023478

RESUMO

Polymorphonuclear leukocytes (PMNL) from human immunodeficiency virus (HIV)-infected patients exhibit accelerated apoptosis and impaired functional activity. HIV protease inhibitor-based therapy produces improvements in both acquired and innate immune responses. Ex vivo and in vitro effects of HIV protease inhibitors on apoptosis and chemotaxis of PMNL were evaluated. After therapy, there was a rapid and significant decrease of PMNL apoptosis, which correlated with increased chemotactic function. These findings were found both in patients with immunological and virological response and in control subjects who showed an increase in CD4(+) T cell counts but no concomitant decline in HIV load. After in vitro treatment with ritonavir or indinavir, apoptosis of both HIV-infected and -uninfected PMNL markedly decreased and correlated with significant enhancement of chemotaxis. These results suggest that HIV protease inhibitors may improve the PMNL function by reducing the apoptosis rate and that this effect may, at least in part, be independent of their antiviral activity.


Assuntos
Apoptose/efeitos dos fármacos , Inibidores da Protease de HIV/farmacologia , Neutrófilos/efeitos dos fármacos , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade , Quimiotaxia de Leucócito/efeitos dos fármacos , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Neutrófilos/fisiologia
8.
Blood ; 96(5): 1979-84, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10961903

RESUMO

Polymorphonuclear leukocyte (PMN) dysfunction has been reported in human immunodeficiency virus (HIV)-infected patients. Interleukin (IL)-15 is a recently discovered cytokine that potentiates antimicrobial functions of normal PMNs. We evaluated the in vitro effect of IL-15 on chemotaxis and fungicidal activity of PMNs from 9 patients with untreated advanced HIV infection, 8 patients with viral suppression after 52 to 130 weeks of highly active antiretroviral therapy (HAART), and 12 patients with treatment failure. We also studied oxidative burst and apoptosis of PMNs in 5 patients with untreated advanced HIV infection. Twelve healthy donors were included as controls. Chemotaxis and fungicidal activity of unprimed PMNs was significantly lower in patients with untreated HIV infection compared with controls. After incubation with IL-15, a significant increase in PMN chemotaxis and fungicidal activity was found; moreover, IL-15 induced a significant reduction in the number of apoptotic HIV(+) PMNs. IL-15 did not modulate oxidative burst of HIV(+) PMNs as measured by chemiluminescence production. The in vitro priming of PMNs with IL-15 determined a complete reversal of defective chemotaxis and killing in all HAART-treated patients with long-term HIV suppression. IL-15 significantly enhanced chemotaxis and fungicidal activity also in patients with HAART failure. In conclusion, IL-15 is an important cytokine in the activation of the functional properties of HIV(+) PMNs, by delaying apoptosis and enhancing chemotaxis and fungicidal activity. The potent stimulant effect of IL-15 on PMN function was observed in antiretroviral naive patients as well as in individuals who were receiving HAART, including those with treatment failure. (Blood. 2000;96:1979-1984)


Assuntos
Infecções por HIV/tratamento farmacológico , Interleucina-15/farmacologia , Neutrófilos/efeitos dos fármacos , Antifúngicos/farmacologia , Antivirais/uso terapêutico , Apoptose/efeitos dos fármacos , Contagem de Linfócito CD4/efeitos dos fármacos , Quimiotaxia de Leucócito/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Infecções por HIV/imunologia , Humanos , Neutrófilos/citologia , Neutrófilos/imunologia , Explosão Respiratória/efeitos dos fármacos
9.
Clin Immunol ; 95(3): 212-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10866128

RESUMO

Increased levels of soluble cell adhesion molecules (sCAM) have been reported in HIV-1 infection and may possibly contribute to altering the adhesion mechanisms of phagocytic cells. We evaluated the effect of highly active antiretroviral therapy (HAART) on plasma levels of sL-selectin, sE-selectin, intercellular cell adhesion molecule-1 (sICAM-1), sICAM-3, and vascular cell adhesion molecule-1 (sVCAM-1). Study participants included 22 HIV-1-infected patients with a CD4+ T-cell count/microl below 500 who were started on a HAART regimen and followed up for 9 months. After the initiation of therapy, plasma sL-selectin concentrations progressively decreased to normal ranges in the majority of our patients (P < 0.001), while no changes in sE-selectin were found. In all patients sICAM-1 remained relatively constant at significantly elevated concentrations during the 9 months of therapy. A significant reduction in plasma concentrations of both sICAM-3 and sVCAM-1 was found; however, the levels of these sCAM were not normalized by HAART and remained significantly elevated throughout the study (P < 0.001). The reduced release of sL-selectin could improve the ability of phagocitic cells to migrate in response to chemotactic stimuli after starting HAART. On the other hand, the persistent elevation of sICAM-1, sICAM-3, and sVCAM-1 could reflect continuous HIV-1-mediated immune activation, despite adequate control of plasma HIV-1 replication by therapy.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Moléculas de Adesão Celular/sangue , Infecções por HIV/tratamento farmacológico , HIV-1 , Adulto , Idoso , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos , Feminino , HIV-1/genética , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Solubilidade
12.
AIDS ; 13(8): 883-90, 1999 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-10371168

RESUMO

OBJECTIVE: To investigate the effect of highly active antiretroviral treatment (HAART) on neutrophil and monocyte function in patients with moderately advanced HIV-1 infection. DESIGN: Eighteen HIV-1-infected patients with CD4 T cell counts below 350/microl, no concomitant active infection, and no previous use of protease inhibitors were treated with indinavir or ritonavir and two reverse-transcriptase inhibitors and were followed up for 9 months. Ten age- and sex-matched healthy subjects were included as controls. METHODS: The functional activity of neutrophils and monocytes was measured by assessing chemotaxis towards a bacterial peptide, killing activity against Candida albicans, and oxidative burst as measured by chemiluminescence production. RESULTS: Neutrophils and monocytes from the treatment group exhibited a significantly diminished baseline chemotactic and fungicidal activity compared with healthy controls (P < 0.001). After starting HAART, there was a significant improvement in chemotaxis and fungicidal activity of phagocytic cells (P < 0.001). Values of chemotaxis reached normal ranges in 13 out of 18 patients (72%) for neutrophils and eight out of 18 (44%) for monocytes, whereas phagocyte killing was rarely restored to normal values (3/18 cases for monocytes and 0/18 for neutrophils). The administration of HAART was also associated with significantly increased phagocyte chemiluminescence production in response to phorbol-12-myristate 13-acetate or opsonized C. albicans (P < 0.01). CONCLUSION: The functional improvement of two critical components of innate antimicrobial immunity, such as neutrophils and monocytes, may contribute to the improved cell-mediated immune responses against opportunistic infections in HAART-treated patients.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Monócitos/imunologia , Neutrófilos/imunologia , Adulto , Idoso , Candida albicans/imunologia , Quimiotaxia de Leucócito , Quimioterapia Combinada , Feminino , Infecções por HIV/imunologia , Inibidores da Protease de HIV/uso terapêutico , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Fagocitose , Estudos Prospectivos , Explosão Respiratória , Inibidores da Transcriptase Reversa/uso terapêutico
14.
FEMS Immunol Med Microbiol ; 21(1): 11-7, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9657316

RESUMO

Monocytes/macrophages from human immunodeficiency virus (HIV)-infected patients had a defect in their ability to kill Rhodococeus equi in vitro, as compared with healthy HIV-seronegative individuals. Virulent and avirulent R. equi strains isolated from humans and horses showed no significant intracellular replicative differences within both HIV-positive and -negative monocytes/macrophages. Infection with R. equi induced the production of nitric oxide (NO) by monocytes/macrophages from healthy individuals, but not by cells from HIV-positive patients. The NO formation was significantly inhibited by L-NG-monomethyl arginine and arginase. However. neither competitive inhibition of NO synthesis from L-arginine with L-NMMA nor depletion of arginine with arginase altered the killing activity of human monocytes/macrophages against R. equi, thus suggesting that L-arginine:NO pathway is not required for the intracellular antirhodococcal mechanisms of human monocytes/macrophages.


Assuntos
Citotoxicidade Imunológica/fisiologia , Infecções por HIV/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Óxido Nítrico/metabolismo , Rhodococcus equi/imunologia , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções por Actinomycetales/imunologia , Animais , Arginase/farmacologia , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Cavalos , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/microbiologia , Monócitos/metabolismo , Monócitos/microbiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitritos/metabolismo , Rhodococcus equi/efeitos dos fármacos , Rhodococcus equi/fisiologia , ômega-N-Metilarginina/farmacologia
15.
Infez Med ; 6(2): 81-86, 1998.
Artigo em Italiano | MEDLINE | ID: mdl-12750570

RESUMO

The aim of the present study was to evaluate the usefulness of the Digene Hybrid Capture System (DHCS) for the detection and quantitation of cytomegalovirus (CMV) DNA in 95 blood samples from 57 HIV-positive patients with low CD4+ T-cell count (<100 cells/ l). The DHCS was compared with pp65 antigenemia assay and the results were correlated with active CMV disease, anti-CMV therapy and occurrence of disease relapses. Our data suggest that the detection of CMV DNA by DHCS seems to be a rapid, sensitive and specific assay for the diagnosis of CMV disease in HIV-infected patients, showing a good correlation with pp65 antigenemia assay. Overall, the DHCS provides a quantitative and objective measure of CMV activity in leukocytes and it may also represent a useful tool for the monitoring of anti-CMV therapy.

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