Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Tipo de estudo
Intervalo de ano de publicação
2.
Sci Rep ; 9(1): 14620, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601823

RESUMO

Galectin-3 (Gal-3) controls intercellular and cell-extracellular matrix interactions during immunological responses. In chronic inflammation, Gal-3 is associated with fibrotic events, regulates B cell differentiation and delays lupus progression. Gal-3 deficient mice (Lgals3-/-) have intense germinal center formation and atypical plasma cell generation correlated to high levels IgG, IgE, and IgA. Here, we used pristane (2,6,10,14-tetramethylpentadecane) to induce lupus-like syndrome in Lgals3-/- and Lgals3+/+ BALB/c mice. Mesentery and peritoneal cells were monitored because promptly react to pristane injected in the peritoneal cavity. For the first time, mesenteric tissues have been associated to the pathogenesis of experimental lupus-like syndrome. In Lgals3+/+ pristane-induced mice, mesentery was hallmarked by intense fibrogranulomatous reaction restricted to submesothelial regions and organized niches containing macrophages and B lymphocytes and plasma cells. In contrast, Lgals3-/- pristane-treated mice had diffuse mesenteric fibrosis affecting submesothelium and peripheral tissues, atypical M1/M2 macrophage polarization and significant DLL1+ cells expansion, suggesting possible involvement of Notch/Delta pathways in the disease. Early inflammatory reaction to pristane was characterized by significant disturbances on monocyte recruitment, macrophage differentiation and dendritic cell (DC) responses in the peritoneal cavity of pristane-induced Lgals3-/- mice. A correlative analysis showed that mesenteric damages in the absence of Gal-3 were directly associated with severe portal inflammation and hepatitis. In conclusion, it has suggested that Gal-3 orchestrates histological organization in the mesentery and prevents lupoid hepatitis in experimental lupus-like syndrome by controlling macrophage polarization, Notch signaling pathways and DC differentiation in mesenteric structures.

3.
Diabetes Res Clin Pract ; 157: 107821, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437560

RESUMO

AIMS: To quantify the static and moving cutaneous sensibility threshold of diabetic patients using a neurosensory device for quantitative pressure detection. METHODS: Three hundred thirty-four (n = 334) patients with type 2 diabetes and no previous history of wounds on the feet were studied using the one- and two-point static (1SP;2 SP) and one- and two-point moving (1MP;2 MP) tests through the pressure-specified sensory device (PSSD) on the cutaneous territory of the dorsal first web, hallux pulp, and medial calcaneal. In addition, patients were evaluated using the Semmes-Weinstein monofilament (SWM) No. 5.07 and tuning fork (128 Hz), which were used as normality parameters to detect the loss of protective sensibility. The same examinations were used to assess the control group (228 nondiabetic). RESULTS: Altered values were observed for the static and moving tests over the three studied nerve territories. In comparing the sensibility threshold between diabetic patients who were sensitive and nonsensitive to SWM 5.07, we observed that this filament is not the most indicated for identifying the loss of sensibility in these patients. The prevalence of patients at risk varied between 85 and 89%. The biochemical marker associated with these high rates was HbA1c (p = 0.02). CONCLUSIONS: Numeric quantification of the pressure threshold allowed us to determine the functional deficit of nerve fibers. Our findings suggest that the neurosensory device should be used as an adjuvant tool to evaluate the degree of loss of sensation on the skin.

4.
J Helminthol ; 94: e50, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30973122

RESUMO

New therapeutic approaches are necessary to control strongyloidiasis due to the side effects of, and resistance to, currently available drugs thiabendazole, albendazole, and ivermectin. This study examined the anthelmintic properties of extracts and isolated compounds from Siparuna guianensis against Strongyloides venezuelensis eggs and larvae, using the egg hatching test (EHT) and larval motility test (LMT). Albendazole (0.025 mg/ml) and ivermectin (0.316 mg/ml) were used as the positive controls for the EHT and LMT assays, respectively. Strongyloides venezuelensis eggs or larvae (±50 specimens) were treated with ethanol extract (0.05-1.0 mg/ml), ethyl acetate and aqueous fractions (0.05-0.8 mg/ml), essential oil (0.2-1.0 mg/ml) and α-bisabolol (0.2-1.0 mg/ml) from S. guianensis, and analysed by optical microscopy after 48 h (EHT), or after 24, 48 and 72 h (LMT). All the tested compounds exhibited ovicidal activity equivalent to the positive control and changed the morphology of the eggs. The S. guianensis ethanol extract and aqueous fraction were as effective as the positive control. Phytochemical analysis of the ethanol extract and fractions revealed the presence of phenolic compounds, tannins and flavonoids. Therefore, S. guianensis is effective against S. venezuelensis eggs and larvae in vitro, and can be considered as a potential alternative treatment for strongyloidiasis.

5.
Oper Dent ; 42(6): 616-625, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28976845

RESUMO

OBJECTIVES: To compare radiopacity and porosity as expressed by the presence of voids in restorations carried out using bulk-fill and incremental filling techniques to restore large mesio-occlusal-distal (MOD) cavities. METHODS: Fifty-five molars with MOD preparations were incrementally filled with Filtek Z-350XT (Z350XT) or bulk-fill composite: Filtek Bulk Fill/Z-350XT (FBF/Z350XT), Venus Bulk Fill/Charisma Diamond (VBF/CHA), SDR/Esthet-X HD (SDR/EST-X), Tetric EvoCeram Bulk Fill (TEC). Digital radiographic images (Vistascan scanner) were taken of restored molars and analyzed at the gingival and isthmus floors. Radiodensity measurements were performed using standardized points symmetrically distributed over each region of composite and tooth structure. Three calibrated evaluators visually assessed the presence of voids. Confidence intervals were calculated, and data were analyzed using analysis of variance and χ2 tests. RESULTS: TEC and VBF/CHA showed significantly higher radiodensities, while the lowest values were observed for FBF/Z350XT and Z350XT. Radiodensity at the cervical regions tended to be greater than that found at the isthmus floor. The lowest incidence of voids was found for VBF/CHA, whereas the incremental insertion technique resulted in the highest rate of voids. CONCLUSION: Bulk-fill composite resin demonstrated an adequate level of radiodensity and a reduced presence of voids compared with the incremental filling technique.


Assuntos
Restauração Dentária Permanente/métodos , Radiografia Dentária Digital , Resinas Compostas/uso terapêutico , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/terapia , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Radiografia Dentária Digital/métodos
6.
Neuropharmacology ; 86: 1-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24978104

RESUMO

Increasing evidence indicates that acute stress disrupts cognitive functions mediated by glutamate-NMDA receptors, although the mechanisms are not fully understood. Here we investigated whether d-serine and glycine, the endogenous co-agonists of the NMDA receptor, are regulated by acute stress. We studied the biochemical and behavioral effects of acute restraint stress in C57BL/6 mice. Acute restraint stress decreased d-serine levels in the prefrontal cortex and glycine levels in the hippocampus. Behaviorally, acute stress impaired memory consolidation in the object recognition task and prepulse inhibition of the startle response. Importantly, d-serine administration (1 g/kg, i.p.) prevented both stress-induced impairments. Taken together, our results show for the first time an interplay between stress and d-serine and warrant further research on the role of d-serine in stress-related disorders.


Assuntos
Transtornos Cognitivos/fisiopatologia , Glicina/metabolismo , Hipocampo/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Serina/metabolismo , Estresse Psicológico/fisiopatologia , Doença Aguda , Animais , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Corticosterona/sangue , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Memória/fisiologia , Camundongos Endogâmicos C57BL , Nootrópicos/administração & dosagem , Córtex Pré-Frontal/efeitos dos fármacos , Inibição Pré-Pulso/efeitos dos fármacos , Inibição Pré-Pulso/fisiologia , Reflexo de Sobressalto/efeitos dos fármacos , Reflexo de Sobressalto/fisiologia , Restrição Física , Serina/administração & dosagem , Estresse Psicológico/complicações , Estresse Psicológico/psicologia
7.
Environ Entomol ; 41(6): 1454-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23321092

RESUMO

Plutella xylostella (L.) is susceptible to both the entomopathogen Bacillus thuringiensis and the predator, Brazilian spined soldier bug [Podisus nigrispinus (Dallas)]. The objective of this study was to measure the interaction between the bacterium B. thuringiensis and the predator P. nigrispinus. We also studied the behavior of P. nigrispinus in relation to its choice between B. thuringiensis-infected and healthy P. xylostellais larvae. In the first treatment, P. nigrispinus nymphs were fed daily with B. thuringiensis-infected P. xylostella larvae and distilled water. In the second treatment, nymphs were fed daily with healthy larvae and a suspension of B. thuringiensis as a source of water. The control nymphs were fed daily with healthy larvae and water. Adult P. nigrispinus were separated by sex, couples were formed, and they were fed daily with P. xylostella larvae derived from the treatments. We followed the development of P. nigrispinus and measured its biological characteristics. On the basis of these data, parameters were determined for the construction of life tables. A choice test was used to compare infected and healthy larvae. The HD1 strain of B. thuringiensis does not affect the biological characteristics of P. nigrispinus when fed infected larvae and water or healthy larvae and B. thuringiensis suspension. Our study shows that integrated management of P. xylostella, a pest of the Brassicaceae, is feasible by using the HD1 strain of B. thuringiensis and the predator P. nigrispinus, because the predator shows no preference for infected or healthy P. xylostella larvae.


Assuntos
Bacillus thuringiensis/fisiologia , Agentes de Controle Biológico , Heterópteros/fisiologia , Mariposas/fisiologia , Animais , Brassicaceae , Feminino , Herbivoria , Heterópteros/microbiologia , Masculino , Mariposas/microbiologia , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Ninfa/fisiologia , Controle Biológico de Vetores/métodos , Comportamento Predatório
8.
Scand J Immunol ; 66(1): 17-25, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17587342

RESUMO

Triiodothyronine (T(3)) exerts several effects on thymus physiology. In this sense, T(3) is known to stimulate thymic microenvironmental cells to enhance the production of extracellular matrix (ECM) moieties, which are relevant in thymocyte migration. Here, we further investigated the in vivo influence of T(3) on ECM production, as well as on ECM-related T-cell migration events. For this, BALB/c mice were subjected to two protocols of T(3) treatment: long-term (30 days) i.p. daily T(3) injections or short-term (16 h) after a single T(3) intrathymic injection. These two treatments did promote an enhancement in the expression of fibronectin and laminin, in both cortex and medullary regions of the thymic lobules. As revealed by the long-term treatment, the expression of ECM protein receptors, including VLA-4, VLA-5 and VLA-6, was also increased in thymocyte subsets issued from T(3)-treated mice. We further used thymic nurse cells (TNC) as an in vitro system to study the ECM-related migration of immature thymocytes in the context of thymic epithelial cells. Even a single intrathymic injection of T(3) resulted in an increase in the ex vivo exit of thymocytes from TNC lymphoepithelial complexes. Accordingly, when we evaluated thymocyte migration in transwell chambers pre-coated with ECM proteins, we found an increase in the numbers of migrating cells, when thymocytes were derived from T(3)-treated mice. Overall, our data show that in vivo intrathymic short-term i.p. long-term T(3) treatments are able to modulate thymocyte migration, probably via ECM-mediated interactions.


Assuntos
Movimento Celular/imunologia , Proteínas da Matriz Extracelular/biossíntese , Tecido Linfoide/citologia , Linfócitos T/metabolismo , Tri-Iodotironina/metabolismo , Animais , Matriz Extracelular/metabolismo , Feminino , Imuno-Histoquímica , Tecido Linfoide/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T/citologia , Linfócitos T/imunologia
10.
Mem Inst Oswaldo Cruz ; 100 Suppl 1: 127-30, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15962111

RESUMO

We previously reported that alloxan-induced diabetes results in reduction in the number and reactivity of mast cells at different body sites. In this study, the influence of diabetes on thymic mast cells was investigated. Thymuses from diabetic rats showed marked alterations including shrinkage, thymocyte depletion, and increase in the extracellular matrix network, as compared to those profiles seen in normal animals. Nevertheless, we noted that the number and reactivity of mast cells remained unchanged. These findings indicate that although diabetes leads to critical alterations in the thymus, the local mast cell population is refractory to its effect. This suggests that thymic mast cells are under a different regulation as compared to those located in other tissues.


Assuntos
Diabetes Mellitus Experimental/patologia , Mastócitos/patologia , Timo/patologia , Aloxano , Animais , Contagem de Células , Masculino , Ratos , Ratos Wistar
11.
Mem. Inst. Oswaldo Cruz ; 100(supl.1): 127-130, Mar. 2005. ilus, graf
Artigo em Inglês | LILACS | ID: lil-402188

RESUMO

We previously reported that alloxan-induced diabetes results in reduction in the number and reactivity of mast cells at different body sites. In this study, the influence of diabetes on thymic mast cells was investigated. Thymuses from diabetic rats showed marked alterations including shrinkage, thymocyte depletion, and increase in the extracellular matrix network, as compared to those profiles seen in normal animals. Nevertheless, we noted that the number and reactivity of mast cells remained unchanged. These findings indicate that although diabetes leads to critical alterations in the thymus, the local mast cell population is refractory to its effect. This suggests that thymic mast cells are under a different regulation as compared to those located in other tissues.


Assuntos
Animais , Masculino , Ratos , Diabetes Mellitus Experimental/patologia , Mastócitos/patologia , Timo/patologia , Aloxano , Contagem de Células , Ratos Wistar
12.
J. bras. aids ; 3(3): 29-33, set. 2002. graf
Artigo em Português | LILACS | ID: lil-327922

RESUMO

O diagnostico laboratorial da infeccao pelo virus da imunodeficiencia humana tipo 1 pode ser feito mediante a aplicacao de testes sorologicos de terceira geracao. Reatividade inespecificas podem, entretanto, ser observadas em diferentess grupos populacionais, para a deteccao de anticorpos contra HIV por metodos imunoenzimaticos, conforme observado na analise de amostras sorologicas de gestantes (3,9 porcento), hepatopatas (3,0 porcento) e populacao pediatrica (1,03 porcento). Os valores de inespecificidade reforcam o conceito de que a deteccao de anticorpos contra HIV deve ser feita pela analise e interpretacao de, ao menos, dois testes de diferentes procedencias, em uma primeira coleta. Metodos de triagem de quarta geracao, que permitem a deteccao simultanea de anticorpos e antigeno p24 do HIV, apresentam sensibilidade comparavel a das metodologias tradicionais, sendo de particular valor no diagnostico precoce da infeccao. Diferentes amostras de sangue de tres pacientes, coletadas em periodos distintos, foram analisadas comparativamente por testes imunoenzimaticos de terceira geracao (Cobas, Axsym e Ortho) e quarta geracao (ELFA HIV DUO). Os resultados demonstram a possibilidade de antecipar a deteccao dos marcadores da infeccao viral em periodos que podem variar de quatro a 12 dias, quando comparados a metodos de terceira geracao, que detectam apenas anticorpos


Assuntos
Soropositividade para HIV
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA