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1.
Scand J Immunol ; 86(1): 40-49, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28426172

RESUMEN

It is well established that helper T cell responses influence resistance or susceptibility to Mycobacterium leprae infection, but the role of more recently described helper T cell subsets in determining severity is less clear. To investigate the involvement of Th17 cells in the pathogenesis of leprosy, we determined the immune profile with variant presentations of leprosy. Firstly, IL-17A, IFN-γ and IL-10 were evaluated in conjunction with CD4+ T cell staining by confocal microscopy of lesion biopsies from tuberculoid (TT) and lepromatous leprosy (LL) patients. Secondly, inflammatory cytokines were measured by multiplex assay of serum samples from Multibacillary (MB, n = 28) and Paucibacillary (PB, n = 23) patients and household contacts (HHC, n = 23). Patients with leprosy were also evaluated for leprosy reaction occurrence: LR+ (n = 8) and LR- (n = 20). Finally, peripheral blood mononuclear cells were analysed by flow cytometry used to determine the phenotype of cytokine-producing cells. Lesions from TT patients were found to have more CD4+ IL-17A+ cells than those from LL patients. Higher concentrations of IL-17A and IL-1ß were observed in serum from PB than MB patients. The highest serum IFN-γ concentrations were, however, detected in sera from MB patients that developed leprosy reactions (MB LR+ ). Together, these results indicate that Th1 cells were associated with both the PB presentation and also with leprosy reactions. In contrast, Th17 cells were associated with an effective inflammatory response that is present in the PB forms but were not predictive of leprosy reactions in MB patients.


Asunto(s)
Mediadores de Inflamación/inmunología , Lepra Paucibacilar/inmunología , Lepra/inmunología , Mycobacterium leprae/inmunología , Células TH1/inmunología , Células Th17/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Niño , Trazado de Contacto , Femenino , Citometría de Flujo , Humanos , Mediadores de Inflamación/sangre , Mediadores de Inflamación/metabolismo , Interferón gamma/sangre , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-10/sangre , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-17/sangre , Interleucina-17/inmunología , Interleucina-17/metabolismo , Interleucina-1beta/sangre , Interleucina-1beta/inmunología , Interleucina-1beta/metabolismo , Lepra/sangre , Lepra/microbiología , Lepra Multibacilar/sangre , Lepra Multibacilar/inmunología , Lepra Multibacilar/microbiología , Lepra Paucibacilar/sangre , Lepra Paucibacilar/microbiología , Masculino , Microscopía Confocal , Persona de Mediana Edad , Mycobacterium leprae/fisiología , Células TH1/metabolismo , Células Th17/metabolismo , Adulto Joven
2.
Epidemiol Infect ; 140(5): 906-15, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21875453

RESUMEN

SUMMARYAn outbreak of meningococcal disease (MD) with severe morbidity and mortality was investigated in midwestern Brazil in order to identify control measures. A MD case was defined as isolation of Neisseria meningitidis, or detection of polysaccharide antigen in a sterile site, or presence of clinical purpura fulminans, or an epidemiological link with a laboratory-confirmed case-patient, between June and August 2008. In 8 out of 16 MD cases studied, serogroup C ST103 complex was identified. Five (31%) cases had neurological findings and five (31%) died. The attack rate was 12 cases/100 000 town residents and 60 cases/100 000 employees in a large local food-processing plant. We conducted a matched case-control study of eight primary laboratory-confirmed cases (1:4). Factors associated with illness in single variable analysis were work at the processing plant [matched odds ratio (mOR) 22, 95% confidence interval (CI) 2·3-207·7, P<0·01], and residing <1 year in Rio Verde (mOR 7, 95% CI 1·11-43·9, P<0·02). Mass vaccination (>10 000 plant employees) stopped propagation in the plant, but not in the larger community.


Asunto(s)
Brotes de Enfermedades , Control de Infecciones/métodos , Infecciones Meningocócicas/epidemiología , Infecciones Meningocócicas/microbiología , Neisseria meningitidis Serogrupo C/aislamiento & purificación , Exposición Profesional , Adolescente , Adulto , Brasil/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/mortalidad , Infecciones Comunitarias Adquiridas/prevención & control , Femenino , Manipulación de Alimentos , Humanos , Lactante , Masculino , Vacunación Masiva/métodos , Infecciones Meningocócicas/mortalidad , Infecciones Meningocócicas/prevención & control , Persona de Mediana Edad , Vacunas Neumococicas/administración & dosificación , Análisis de Supervivencia , Adulto Joven
3.
Braz J Biol ; 70(2): 435-42, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20379652

RESUMEN

Unisexual Trichogramma forms have attracted much attention due to their potential advantages as biocontrol agents. Fitness studies have been performed and understanding the cost that Wolbachia may inflict on their hosts will help in deciding if Wolbachia infected (unisexual) forms are indeed better than sexual forms when used in biological control programmes. The influence of Wolbachia on the foraging behaviour (including walking activity and speed) of T. atopovirilia is reported in this paper. Temperature strongly affected T. atopovirilia female walking activity, but Wolbachia infected and uninfected females differed in none of the behavioural components that were measured such as walking activity and walking speed. Walking activity was highest at 25 masculineC and differed significantly from that at 20 and 15 masculineC. Trichogramma wasps were highly affected at 15 masculineC. Behaviour analysis with females showed that female wasps spend most of the time on drilling + ovipositing on host eggs followed by host drumming and walking while drumming. The parasitism rate and number of offspring did not differ significantly between infected and cured Trichogramma females. Biological control implications of these findings are discussed.


Asunto(s)
Oviposición/fisiología , Avispas/microbiología , Wolbachia/fisiología , Animales , Femenino , Avispas/fisiología
4.
Proc Biol Sci ; 271(1538): 509-15, 2004 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-15129961

RESUMEN

The intracellular bacterium Wolbachia is one of the most common symbionts in arthropods and, because of its manipulative effects on host reproduction, is assumed to be an important factor in several evolutionary processes. These bacteria are mainly vertically transmitted from mother to daughter through the egg cytoplasm, and horizontal transmission is generally assumed to be rare. Here, we show natural inter- and intraspecific horizontal transfer of parthenogenesis-inducing Wolbachia between parasitoid wasps of the genus Trichogramma. Horizontal transfer was observed when infected and uninfected larvae shared the same host egg. This is the first report, to our knowledge, on interspecific horizontal transfer of Wolbachia between closely related sympatric species. Some originally uninfected immature wasps acquired Wolbachia while inside the host egg, but not all of these newly infected females exhibited the parthenogenesis phenotype. In general, intraspecific horizontal transfer was more successful than interspecific transfer. Wolbachia underwent vertical transmission in the new species but the infection tended to be lost within several generations. Our results have important implications for understanding the evolution of Wolbachia-host associations.


Asunto(s)
Transmisión de Enfermedad Infecciosa , Partenogénesis/fisiología , Avispas/microbiología , Wolbachia/genética , Animales , Proteínas de la Membrana Bacteriana Externa/genética , Cartilla de ADN , Femenino , Larva/microbiología , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN , Especificidad de la Especie , Avispas/fisiología
5.
Rev Odontol Univ Sao Paulo ; 4(4): 314-7, 1990.
Artículo en Portugués | MEDLINE | ID: mdl-2135446

RESUMEN

The adhesive fixed partial denture is a relatively new alternative in Dental Prostheses area, then it needs many studies in order to reach technique improvement. This work has the objective of studying the behavior of a copper-aluminium and two nickel-chrom dental alloys that were subjected to electrolytical etching with two experimental solutions and an electrolytic solution commented by TANAKA et alii, 1979. After weight-loss studies we can conclude that the alloy composition is a fundamental factor and to each alloy should be developed specifics electrolytical solutions.


Asunto(s)
Aleaciones Dentales/química , Electrólisis/métodos , Aluminio , Aleaciones de Cromo/química , Cobre , Dentadura Parcial Fija con Resina Consolidada
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