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1.
J Virol ; 93(10)2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30814287

RESUMO

HIV controllers (HIC) maintain control of HIV replication without combined antiretroviral treatment (cART). The mechanisms leading to virus control are not fully known. We used gene expression and cellular analyses to compare HIC and HIV-1-infected individuals under cART. In the blood, HIC are characterized by a low inflammation, a downmodulation of natural killer inhibitory cell signaling, and an upregulation of T cell activation gene expression. This balance that persists after stimulation of cells with HIV antigens was consistent with functional analyses showing a bias toward a Th1 and cytotoxic T cell response and a lower production of inflammatory cytokines. Taking advantage of the characterization of HIC based upon their CD8+ T lymphocyte capacity to suppress HIV-infection, we show here that unsupervised analysis of differentially expressed genes fits clearly with this cytotoxic activity, allowing the characterization of a specific signature of HIC. These results reveal significant features of HIC making the bridge between cellular function, gene signatures, and the regulation of inflammation and killing capacity of HIV-specific CD8+ T cells. Moreover, these genetic profiles are consistent through analyses performed from blood to peripheral blood mononuclear cells and T cells. HIC maintain strong HIV-specific immune responses with low levels of inflammation. Our findings may pave the way for new immunotherapeutic approaches leading to strong HIV-1-specific immune responses while minimizing inflammation.IMPORTANCE A small minority of HIV-infected patients, called HIV controllers (HIC), maintains spontaneous control of HIV replication. It is therefore important to identify mechanisms that contribute to the control of HIV replication that may have implications for vaccine design. We observed a low inflammation, a downmodulation of natural killer inhibitory cell signaling, and an upregulation of T-cell activation gene expression in the blood of HIC compared to patients under combined antiretroviral treatment. This profile persists following in vitro stimulation of peripheral blood mononuclear cells with HIV antigens, and was consistent with functional analyses showing a Th1 and cytotoxic T cell response and a lower production of inflammatory cytokines. These results reveal significant features of HIC that maintain strong HIV-specific immune responses with low levels of inflammation. These findings define the immune status of HIC that is probably associated with the control of viral load.


Assuntos
Infecções por HIV/imunologia , Imunidade Inata/imunologia , Ativação Linfocitária/imunologia , Adulto , Idoso , Antirretrovirais/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Regulação Viral da Expressão Gênica/genética , Antígenos HIV , Infecções por HIV/metabolismo , HIV-1/metabolismo , HIV-1/patogenicidade , Humanos , Inflamação/imunologia , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Células Th1/imunologia , Carga Viral , Replicação Viral/efeitos dos fármacos
2.
Acta Derm Venereol ; 96(1): 29-34, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26039581

RESUMO

No specific biomarkers for prognostication or evaluation of tumour load in melanoma have been reported to our knowledge. MicroRNAs (miRNAs) are strongly implicated in oncogenesis and tumour progression, and their circulating forms have been studied as potential biomarkers in oncology. The aim of this prospective study was to identify a melanoma-specific profile of plasma miRNAs. A screening phase, using RNA microarray, was conducted on plasma from 14 patients with metastatic melanoma and 5 healthy subjects. Selected miRNAs were analysed by RTqPCR in 2 independent training and validation cohorts including, respectively, 29 and 31 patients and 16 and 43 control subjects. A profile of 2 miRNAs (miR-1246 and miR-185) significantly associated with metastatic melanoma with a sensitivity of 90.5% and a specificity of 89.1% was identified. This plasma miRNA profile may become an accurate non-invasive biomarker for melanoma.


Assuntos
Biomarcadores Tumorais/sangue , Perfilação da Expressão Gênica , Melanoma/sangue , MicroRNAs/sangue , Neoplasias Cutâneas/sangue , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Perfilação da Expressão Gênica/métodos , Humanos , Melanoma/genética , Melanoma/secundário , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
3.
Mem Inst Oswaldo Cruz ; 108(4): 399-407, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23828008

RESUMO

A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents--that we reviewed here--which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Roedores/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Humanos , Masculino , Níger/epidemiologia , Ratos , Doenças dos Roedores/diagnóstico , Roedores , Estudos Soroepidemiológicos , Toxoplasmose Animal/diagnóstico , População Urbana
4.
Front Immunol ; 10: 874, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31105698

RESUMO

The goal of HIV therapeutic vaccination is to induce HIV-specific immune response able to control HIV replication. We previously reported that vaccination with ex vivo generated Dendritic Cells (DC) loaded with HIV-lipopeptides in HIV-infected patients (n = 19) on antiretroviral therapy (ART) was well-tolerated and immunogenic. Vaccine-elicited HIV-specific T cell responses were associated with improved control of viral replication following antiretroviral interruption (ATI from w24 to w48). We show an inverse relationship between HIV-specific responses (production of IL-2, IL-13, IL-21, IFN-g, CD4 polyfunctionality, i.e., production of at least two cytokines) and the peak of viral load during ATI. Here we have performed an integrative systems vaccinology analysis including: (i) post vaccination (w16) immune responses assessed by cytometry, cytokine secretion, and Interferon-γ ELISPOT assays; (ii) whole blood and cellular gene expression measured during vaccination; and (iii) viral parameters following ATI, with the objective to disentangle the relationships between these markers and to identify vaccine signatures. During vaccination, 69 gene expression modules out of 260 varied significantly including (by order of significance) modules related to inflammation (Chaussabel Modules M3.2, M4.13, M4.6, M5.7, M7.1, M4.2), plasma cells (M4.11) and T cells (M4.1, 4.15). Cellular immune responses were positively correlated to genes belonging to T cell functional modules (M4.1, M4.15) at w16 and negatively correlated to genes belonging to inflammation modules (M7.1, M5.7, M3.2, M4.13, M4.2). More specifically, we show that prolonged increased abundance of inflammatory gene pathways related to toll-like receptor signaling (especially TLR4) are associated with both lower vaccine immune responses and control of viral replication post ATI. Further comparison of DC vaccine gene signatures with previously reported non-HIV vaccine signatures, such as flu and pneumococcal vaccines, revealed common pathways across vaccines. Overall, these results show that too long duration and too high intensity of vaccine inflammatory responses hamper the magnitude of effector responses.


Assuntos
Vacinas contra a AIDS/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Infecções por HIV/genética , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Transcriptoma , Vacinas contra a AIDS/administração & dosagem , Adulto , Células Sanguíneas/imunologia , Células Sanguíneas/metabolismo , Biologia Computacional/métodos , Citocinas/metabolismo , Feminino , Perfilação da Expressão Gênica , Antígenos HIV , Infecções por HIV/prevenção & controle , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados da Assistência ao Paciente , Texas , Vacinação , Carga Viral
5.
J Clin Invest ; 129(5): 1960-1971, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30843873

RESUMO

BACKGROUND: Systems vaccinology allows cutting-edge analysis of innate biomarkers of vaccine efficacy. We have been exploring novel strategies to shape the adaptive immune response, by targeting innate immune cells through novel immunization routes. METHODS: This randomized phase I/II clinical study (n=60 healthy subjects aged 18-45 years old) used transcriptomic analysis to discover early biomarkers of immune response quality after transcutaneous (t.c.), intradermal (i.d.), and intramuscular (i.m.) administration of a trivalent influenza vaccine (TIV season 2012-2013) (1:1:1 ratio). Safety and immunogenicity (hemagglutinin inhibition (HI), microneutralization (MN) antibodies and CD4, CD8 effector T cells) were measured at baseline Day (D)0 and at D21. Blood transcriptome was analyzed at D0 and D1. RESULTS: TIV-specific CD8+GranzymeB+(GRZ) T cells appeared in more individuals immunized by the t.c. and i.d. routes, while immunization by the i.d. and i.m. routes prompted high levels of HI antibody titers and MN against A/H1N1 and A/H3N2 influenza viral strains. The early innate gene signature anticipated immunological outcome by discriminating two clusters of individuals with either distinct humoral or CD8 cytotoxic responses. Several pathways explained this dichotomy confirmed by nine genes and serum level of CXCL10 were correlated with either TIV-specific cytotoxic CD8+GRZ+ T-cell or antibody responses. A logistic regression analysis demonstrated that these nine genes and serum levels of CXCL10 (D1/D0) best foreseen TIV-specific CD8+GRZ+ T-cell and antibody responses at D21. CONCLUSION: This study provides new insight into the impact of immunization routes and innate signature in the quality of adaptive immune responses.


Assuntos
Imunidade Humoral , Vacinas contra Influenza/imunologia , Linfócitos T Citotóxicos/imunologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Formação de Anticorpos , Linfócitos T CD8-Positivos/citologia , Quimiocina CXCL10/metabolismo , Feminino , Perfilação da Expressão Gênica , Granzimas/metabolismo , Humanos , Imunidade Celular , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Transcriptoma , Vacinação , Adulto Jovem
6.
PLoS One ; 13(11): e0207794, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30500852

RESUMO

HIV-1 infection can be controlled by anti-retroviral drug therapy, but this is a lifetime treatment and the virus remains latent and rapidly rebounds if therapy is stopped. HIV-1-infected individuals under this drug regimen have increased rates of cancers, cardiovascular diseases, and autoimmunity due to compromised immunity. A therapeutic vaccine boosting cellular immunity against HIV-1 is therefore desirable and, possibly combined with other immune modulating agents, could obviate the need for long-term drug therapies. An approach to elicit strong T cell-based immunity is to direct virus protein antigens specifically to dendritic cells (DCs), which are the key cell type for controlling immune responses. For eliciting therapeutic cellular immunity in HIV-1-infected individuals, we developed vaccines comprised of five T cell epitope-rich regions of HIV-1 Gag, Nef, and Pol (HIV5pep) fused to monoclonal antibodies that bind either, the antigen presenting cell activating receptor CD40, or the endocytic dendritic cell immunoreceptor DCIR. The study aimed to demonstrate vaccine safety, establish efficacy for broad T cell responses in both primed and naïve settings, and identify one candidate vaccine for human therapeutic development. The vaccines were administered to Rhesus macaques by intradermal injection with poly-ICLC adjuvant. The animals were either i) naïve or, ii) previously primed with modified vaccinia Ankara vector (MVA) encoding HIV-1 Gag, Pol, and Nef (MVA GagPolNef). In the MVA-primed groups, both DC-targeting vaccinations boosted HIV5pep-specific blood CD4+ T cells producing multiple cytokines, but did not affect the MVA-elicited CD8+ T cell responses. In the naive groups, both DC-targeting vaccines elicited antigen-specific polyfunctional CD4+ and CD8+ T cell responses to multiple epitopes and these responses were unchanged by a subsequent MVA GagPolNef boost. In both settings, the T cell responses elicited via the CD40-targeting vaccine were more robust and were detectable in all the animals, favoring further development of the CD40-targeting vaccine for therapeutic vaccination of HIV-1-infected individuals.


Assuntos
Vacinas contra a AIDS/imunologia , Antígenos CD40/imunologia , Células Dendríticas/imunologia , Epitopos de Linfócito T/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Receptores Imunológicos/imunologia , Animais , Macaca mulatta , Masculino , Terapia de Alvo Molecular
7.
J Invest Dermatol ; 136(9): 1768-1780, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27206704

RESUMO

Hidradenitis suppurativa (HS) is a chronic, inflammatory, debilitating, follicular disease of the skin. Despite a high prevalence in the general population, the physiopathology of HS remains poorly understood. The use of antibiotics and immunosuppressive agents for therapy suggests a deregulated immune response to microflora. Using cellular and gene expression analyses, we found an increased number of infiltrating CD4(+) T cells secreting IL-17 and IFN-γ in perilesional and lesional skin of patients with HS. By contrast, IL-22-secreting CD4(+) T cells are not enriched in HS lesions contrasting with increased number of those cells in the blood of patients with HS. We showed that keratinocytes isolated from hair follicles of patients with HS secreted significantly more IL-1ß, IP-10, and chemokine (C-C motif) ligand 5 (RANTES) either constitutively or on pattern recognition receptor stimulations. In addition, they displayed a distinct pattern of antimicrobial peptide production. These findings point out a functional defect of keratinocytes in HS leading to a balance prone to inflammatory responses. This is likely to favor a permissive environment for bacterial infections and chronic inflammation characterizing clinical outcomes in patients with HS.


Assuntos
Citocinas/metabolismo , Hidradenite Supurativa/sangue , Inflamação/fisiopatologia , Queratinócitos/metabolismo , Adulto , Células Cultivadas , Citocinas/imunologia , Progressão da Doença , Feminino , Citometria de Fluxo , Hidradenite Supurativa/fisiopatologia , Humanos , Inflamação/metabolismo , Queratinócitos/patologia , Masculino , Análise em Microsséries/métodos , RNA/metabolismo , Medição de Risco , Estudos de Amostragem , Estatísticas não Paramétricas , Adulto Jovem
8.
PLoS One ; 11(4): e0153484, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27077384

RESUMO

Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in non-human primates (NHPs) of Env gp140 protein fused to a humanized anti-LOX-1 recombinant antibody for delivering Env directly to LOX-1-bearing antigen presenting cells, especially dendritic cells (DC). LOX-1, or 1ectin-like oxidized low-density lipoprotein (LDL) receptor-1, is expressed on various antigen presenting cells and endothelial cells, and is involved in promoting humoral immune responses. The anti-LOX-1 Env gp140 fusion protein was tested for priming immune responses and boosting responses in animals primed with replication competent NYVAC-KC Env gp140 vaccinia virus. Anti-LOX-1 Env gp140 vaccination elicited robust cellular and humoral responses when used for either priming or boosting immunity. Co-administration with Poly ICLC, a TLR3 agonist, was superior to GLA, a TLR4 agonist. Both CD4+ and CD8+ Env-specific T cell responses were elicited by anti-LOX-1 Env gp140, but in particular the CD4+ T cells were multifunctional and directed to multiple epitopes. Serum IgG and IgA antibody responses induced by anti-LOX-1 Env gp140 against various gp140 domains were cross-reactive across HIV-1 clades; however, the sera neutralized only HIV-1 bearing sequences most similar to the clade C 96ZM651 Env gp140 carried by the anti-LOX-1 vehicle. These data, as well as the safety of this protein vaccine, justify further exploration of this DC-targeting vaccine approach for protective immunity against HIV-1.


Assuntos
HIV-1/imunologia , Receptores Depuradores Classe E/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Vacinas contra a AIDS/imunologia , Animais , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Humanos , Macaca mulatta , Masculino , Camundongos , Proteínas Recombinantes de Fusão/imunologia , Linfócitos T/imunologia
9.
Clin J Pain ; 27(9): 790-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21593663

RESUMO

OBJECTIVE: Whether schizophrenic patients are hypoalgesic or feel pain in the same manner as unaffected individuals can affect the primary care of schizophrenic patients, which often involves an assessment of pain severity made by a medical provider. This study was developed to explore the pain sensitivity of schizophrenics under conditions similar to those of a medical examination that included investigating for sites of pain. METHODS: We developed 2 experimental models of pain induction using either pressure or ischemia and used them with 35 schizophrenic patients and 35 controls to record: (1) the stimulus intensity required to induce moderate pain; and (2) the pain intensity induced by a predetermined level of pressure. Clinical data were also collected for the schizophrenic group. RESULTS: Schizophrenic patients needed less pressure (P=0.006) and a shorter duration of ischemia (P<0.001) than controls to record moderate pain, and they felt more pain from a fixed pressure stimulus (P<0.001). Pain histories for the previous 6 months and the heart rate variations that occurred during the tests did not differ between the groups. Pain responses were unrelated to the clinical characteristics of the schizophrenic patients, although hallucination production correlated with the pain felt during the fixed pressure test. DISCUSSION: Under these conditions, schizophrenic patients were hypersensitive to pain induction compared with normal individuals. The hypoalgesia typically associated with schizophrenic patients may correspond to fewer than normal reports of pain, rather than to impaired sensations of pain. This should be taken into account during routine medical practice.


Assuntos
Hiperalgesia/fisiopatologia , Limiar da Dor/fisiologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adulto , Distribuição de Qui-Quadrado , Feminino , Humanos , Isquemia/complicações , Masculino , Pessoa de Meia-Idade , Medição da Dor , Pressão/efeitos adversos , Psicofísica , Esquizofrenia/diagnóstico , Sensibilidade e Especificidade
10.
Eur J Pain ; 15(5): 509-14, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21036635

RESUMO

OBJECTIVE: The purpose of the study was to evaluate the efficacy and safety of dolasetron for symptomatic relief of pain associated with fibromyalgia (FM). METHODS: This prospective, double-blind, placebo-controlled trial randomly assigned 60 patients with FM to receive placebo (n = 31) or dolasetron (n = 29) 12.5mg/d via the intravenous route on 4 days at baseline (M0), 1 month (M1), 2 months (M2) and 3 months (M3) with follow-up to month 12. The primary outcome variable was the reduction in pain intensity measured by visual analogue scale (VAS) between M0 and M3. The secondary outcome variables were patient global impression of change (PGIC), the FM impact questionnaire, assessment of quality of life (SF-36), the hospital anxiety and depression scale, the manual tender point count, and functional symptoms associated with FM. RESULTS: Reduction in pain intensity at M3 was significantly greater in dolasetron-treated patients (p = 0.04, -21.3 on a 0-100 scale) compared with placebo controls (-5.9). More patients in the dolasetron group had ≥ 30% and ≥ 50% improvement in pain (42.5% and 28% respectively in the dolasetron group versus 25% and 16% in the placebo group). The PGIC was significantly greater in the dolasetron group at M3 (p = 0.02). The other secondary outcomes failed to reach statistical significance. The most common adverse events were constipation, nausea, dizziness and headache, with no significant differences between the two groups. CONCLUSION: Intermittent IV dolasetron was safe and efficacious for the reduction of pain intensity associated with FM at 3 months.


Assuntos
Fibromialgia/tratamento farmacológico , Indóis/administração & dosagem , Dor/tratamento farmacológico , Quinolizinas/administração & dosagem , Antagonistas do Receptor 5-HT3 de Serotonina/administração & dosagem , Adolescente , Adulto , Idoso , Doença Crônica , Método Duplo-Cego , Seguimentos , Humanos , Indóis/efeitos adversos , Injeções Intravenosas , Pessoa de Meia-Idade , Placebos , Estudos Prospectivos , Qualidade de Vida , Quinolizinas/efeitos adversos , Antagonistas do Receptor 5-HT3 de Serotonina/efeitos adversos , Resultado do Tratamento , Adulto Jovem
11.
Microb Drug Resist ; 17(1): 31-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20809835

RESUMO

Antimicrobial resistance of Streptococcus pneumoniae in France is closely monitored by the pneumococcus surveillance network, founded in 1995, which collects data from regional observatories (Observatoire Régionaux du Pneumocoque [ORP]). In 2007, 23 ORPs analyzed the antibiotic susceptibility of 5,302 isolates of S. pneumoniae recovered in France from cerebrospinal fluid, blood, middle ear fluid, and pleural fluid, as well as from adult respiratory samples. The study showed that 38.2% of the strains were nonsusceptible to penicillin, 19.3% nonsusceptible to amoxicillin, and 10.5% nonsusceptible to cefotaxime. The percentage of pneumococcus nonsusceptible to penicillin varied according to both the sample and the age of the patient (child/adult): blood (27.8%/32.5%), cerebrospinal fluid (33.7%/34.6%), middle ear fluid (60.2%/27.5%), and pleural fluid (50.0%/31.0%). Between 2003 and 2007, the frequency of penicillin resistance in invasive pneumococcal disease gradually decreased from 46.4% to 29.0% in children and from 43.8% to 32.7% in adults. This decrease coincided with the introduction of a seven-valent pneumococcal conjugate vaccine into immunization programs and with a general reduction in levels of antibiotic consumption in France.


Assuntos
Antibacterianos/farmacologia , Infecções Pneumocócicas/tratamento farmacológico , Streptococcus pneumoniae/efeitos dos fármacos , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla , França/epidemiologia , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Programas de Imunização , Lactente , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/administração & dosagem , Vigilância da População/métodos
12.
PLoS Negl Trop Dis ; 4(11): e876, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-21072237

RESUMO

BACKGROUND: Toxoplasma gondii is found worldwide, but distribution of its genotypes as well as clinical expression of human toxoplasmosis varies across the continents. Several studies in Europe, North America and South America argued for a role of genotypes in the clinical expression of human toxoplasmosis. Genetic data concerning T. gondii isolates from Africa are scarce and not sufficient to investigate the population structure, a fundamental analysis for a better understanding of distribution, circulation, and transmission. METHODOLOGY/PRINCIPAL FINDINGS: Seropositive animals originating from urban and rural areas in Gabon were analyzed for T. gondii isolation and genotyping. Sixty-eight isolates, including one mixed infection (69 strains), were obtained by bioassay in mice. Genotyping was performed using length polymorphism of 13 microsatellite markers located on 10 different chromosomes. Results were analyzed in terms of population structure by Bayesian statistical modeling, Neighbor-joining trees reconstruction based on genetic distances, F(ST) and linkage disequilibrium. A moderate genetic diversity was detected. Three haplogroups and one single genotype clustered 27 genotypes. The majority of strains belonged to one haplogroup corresponding to the worldwide Type III. The remaining strains were distributed into two haplogroups (Africa 1 and 3) and one single genotype. Mouse virulence at isolation was significantly different between haplogroups. Africa 1 haplogroup was the most virulent. CONCLUSION: Africa 1 and 3 haplogroups were proposed as being new major haplogroups of T. gondii circulating in Africa. A possible link with strains circulating in South and Central America is discussed. Analysis of population structure demonstrated a local spread within a rural area and strain circulation between the main cities of the country. This circulation, favored by human activity could lead to genetic exchanges. For the first time, key epidemiological questions were addressed for the West African T. gondii population, using the high discriminatory power of microsatellite markers, thus creating a basis for further epidemiological and clinical investigations.


Assuntos
Variação Genética , Toxoplasma/genética , Toxoplasma/patogenicidade , Toxoplasmose/parasitologia , África , Animais , Gabão , Genótipo , Humanos , Camundongos , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Toxoplasma/classificação , Toxoplasma/isolamento & purificação , Virulência
13.
J Infect Dis ; 199(8): 1155-67, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19265484

RESUMO

We report the genotyping analysis of Toxoplasma gondii isolates in samples collected from 88 immunocompromised patients, along with clinical and epidemiological data. Most of these samples were collected in France during the current decade by the Toxoplasma Biological Resource Center. Lack of specific anti-Toxoplasma treatment, pulmonary toxoplasmosis, and involvement of multiple organs were the 3 main risk factors associated with death for this patient group. Genotyping results with 6 microsatellite markers showed that type II isolates were predominant among patients who acquired toxoplasmic infection in Europe. Non-type II isolates included 13 different genotypes and were mainly collected from patients who acquired toxoplasmosis outside Europe. Type III was the second most common genotype recovered from patients, whereas type I was rare in our population. Three nonarchetypal genotypes were repeatedly recovered from different patients who acquired the infection in sub-Saharan Africa (genotypes Africa 1 and Africa 2) and in the French West Indies (genotype Caribbean 1). The distribution of genotypes (type II vs. non-type II) was not significantly different when patients were stratified by underlying cause of immunosuppression, site of infection, or outcome. We conclude that in immunocompromised patients, host factors are much more involved than parasite factors in patients' resistance or susceptibility to toxoplasmosis.


Assuntos
Hospedeiro Imunocomprometido , Toxoplasma/genética , Toxoplasmose/parasitologia , Animais , Encefalite/complicações , Encefalite/mortalidade , Encefalite/parasitologia , França/epidemiologia , Genótipo , Infecções por HIV/complicações , Infecções por HIV/imunologia , Humanos , Pneumopatias Parasitárias/complicações , Pneumopatias Parasitárias/mortalidade , Pneumopatias Parasitárias/parasitologia , Toxoplasma/classificação , Toxoplasmose/complicações , Toxoplasmose/mortalidade
14.
Mem. Inst. Oswaldo Cruz ; 108(4): 399-407, jun. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-678295

RESUMO

A serological survey of Toxoplasma gondii was conducted on 766 domestic and peridomestic rodents from 46 trapping sites throughout the city of Niamey, Niger. A low seroprevalence was found over the whole town with only 1.96% of the rodents found seropositive. However, differences between species were important, ranging from less than 2% in truly commensal Mastomys natalensis, Rattus rattus and Mus musculus, while garden-associated Arvicanthis niloticus displayed 9.1% of seropositive individuals. This is in line with previous studies on tropical rodents - that we reviewed here - which altogether show that Toxoplasma seroprevalence in rodent is highly variable, depending on many factors such as locality and/or species. Moreover, although we were not able to decipher statistically between habitat or species effect, such a contrast between Nile grass rats and the other rodent species points towards a potentially important role of environmental toxoplasmic infection. This would deserve to be further scrutinised since intra-city irrigated cultures are extending in Niamey, thus potentially increasing Toxoplasma circulation in this yet semi-arid region. As far as we are aware of, our study is one of the rare surveys of its kind performed in Sub-Saharan Africa and the first one ever conducted in the Sahel.


Assuntos
Animais , Humanos , Masculino , Ratos , Anticorpos Antiprotozoários/sangue , Doenças dos Roedores/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Níger/epidemiologia , Roedores , Doenças dos Roedores/diagnóstico , Estudos Soroepidemiológicos , Toxoplasmose Animal/diagnóstico , População Urbana
15.
Vaccine ; 26(23): 2899-905, 2008 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-18440675

RESUMO

In search of reducing vaccine production costs', a recombinant M13 phage version of the anti-cysticercosis tripeptide vaccine (S3Pvac) was developed. The efficacy of S3Pvac-Phage vs. placebo was evaluated in a randomized trial that included 1,047 rural pigs in 16 villages of Central Mexico. Three to five months after vaccination 530 pigs were examined by tongue inspection. At 5-27 months of age, 331 pigs (197 vaccinated/134 controls) were inspected at necropsy. Vaccination reduced 70% the frequency of tongue cysticercosis and, based on necropsy, 54% of muscle-cysticercosis and by 87% the number of cysticerci.


Assuntos
Antígenos de Helmintos/imunologia , Bacteriófago M13/imunologia , Cisticercose/imunologia , Cisticercose/veterinária , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Taenia solium/imunologia , Vacinas/imunologia , Vacinas/uso terapêutico , Envelhecimento/imunologia , Animais , Antígenos de Helmintos/biossíntese , Bacteriófago M13/metabolismo , Cisticercose/prevenção & controle , México , População Rural , Suínos , Doenças dos Suínos/parasitologia , Vacinas de Produtos Inativados/imunologia , Aumento de Peso/efeitos dos fármacos
16.
J Strength Cond Res ; 21(3): 768-75, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17685721

RESUMO

This study examined the impact of 4 weeks of either complete cessation of training (DTR) or a tapering period (TAP; short-term reduction of the strength training volume, while the intensity is kept high), subsequent to 16 weeks of periodized heavy resistance training (PRT) on strength/power gains and the underlying physiologic changes in basal circulating anabolic/catabolic hormones in strength-trained athletes. Forty-six physically active men were matched and randomly assigned to a TAP (n = 11), DTR (n = 14), or control group (C; n = 21), subsequent to a 16-week PRT program. Muscular and power testing and blood draws to determine basal hormonal concentrations were conducted before the initiation of training (T0), after 16 weeks of training (T1), and after 4 weeks of either DTR or TAP (T2). Short-term DTR (4 weeks) results in significant decreases in maximal strength (-6 to -9%) and muscle power output (-17 and -14%) of the arm and leg extensor muscles. However, DTR had a significant (p < 0.01) larger effect on muscle power output more than on strength measurements of both upper and lower extremity muscles. Short-term (4 weeks) TAP reached further increases for leg (2%) and arm (2%) maximal strength, whereas no further changes were observed in both upper and lower muscle power output. Short-term DTR resulted in a tendency for elevation resting serum insulin-like growth factor (IGF)-1 concentrations, whereas the corresponding TAP experienced elevation in resting serum insulin-like binding protein-3 (IGFBP-3). These data indicated that DTR may induce larger declines in muscle power output than in maximal strength, whereas TAP may result in further strength enhancement (but not muscle power), mediated, in part, by training-related differences in IGF-1 and IGFBP-3 concentrations.


Assuntos
Exercício Físico/fisiologia , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Educação Física e Treinamento/métodos , Testosterona/sangue , Adulto , Análise de Variância , Composição Corporal , Ensaio de Imunoadsorção Enzimática , Humanos , Hidrocortisona/sangue , Masculino , Contração Muscular/fisiologia , Resistência Física/fisiologia , Esforço Físico/fisiologia , Espanha , Levantamento de Peso/fisiologia
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