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81.
There are evidences that Giardia trophozoites contain and/or release proteolytic enzymes that may be implicated in pathogenesis of giardiasis. This report describes a preliminary characterization of the proteolytic activity in excretory/secretory (E/S) products of Giardia duodenalis trophozoites of an axenic Brazilian strain (BTU-11) and the reference strain Portland 1 (P1). The protease activity of E/S products in conditioned medium by trophozoites of each strain was analyzed using substrate (gelatin and collagen) impregnated SDS-PAGE and hemoglobin assay. The protease characterization was based on inhibition assays including synthetic inhibitors. Proteolytic products were detected in the conditioned medium by trophozoites of both assayed strains. In the gels containing copolymerized gelatin and collagen, E/S products promoted degradation of the substrates and the most evident proteolysis zones were distributed in the migration regions of 77 to 18 kDa and 145 to 18 kDa, respectively, in the patterns of gelatinolytic and collagenolytic activities. Degradation of hemoglobin was also observed, and the pattern of hydrolysis was similar in both E/S products assayed. Inhibition assays showed that the main proteolytic activity in both E/S products is due to cysteine proteases although the presence of serine proteases was also indicated, mainly in the hydrolysis of hemoglobin.  相似文献   
82.
The objective of this study was to analyze the scientific production in collective health regarding which validated questionnaires are being used to evaluate adherence to hypertension treatments. This integrative review was performed on the SciELO, MEDLINE and LILACS databases. Nine studies were selected, which used seven questionnaires: Moriski-Green Test, Cuestionário de Valoración de Adherencia, Cuestionário MBG, Questionário QAM-Q, Haynes Test, Escala de Conductas em Salud, and Hill-Bone compliance Scale. We concluded that the evaluation of hypertension treatment adherence is still an field open of research, due to the fact that the different instruments used have limitations, and there is no ideal method yet identified.  相似文献   
83.
Lepromatous macrophages possess a regulatory phenotype that contributes to the immunosuppression observed in leprosy. CD163, a scavenger receptor that recognizes hemoglobin–haptoglobin complexes, is expressed at higher levels in lepromatous cells, although its functional role in leprosy is not yet established. We herein demonstrate that human lepromatous lesions are microenvironments rich in IDO+CD163+. Cells isolated from these lesions were CD68+IDO+CD163+ while higher levels of sCD163 in lepromatous sera positively correlated with IL‐10 levels and IDO activity. Different Myco‐bacterium leprae (ML) concentrations in healthy monocytes likewise revealed a positive correlation between increased concentrations of the mycobacteria and IDO, CD209, and CD163 expression. The regulatory phenotype in ML‐stimulated monocytes was accompanied by increased TNF, IL‐10, and TGF‐β levels whereas IL‐10 blockade reduced ML‐induced CD163 expression. The CD163 blockade reduced ML uptake in human monocytes. ML uptake was higher in HEK293 cells transfected with the cDNA for CD163 than in untransfected cells. Simultaneously, increased CD163 expression in lepromatous cells seemed to be dependent on ML uptake, and contributed to augmented iron storage in lepromatous macrophages. Altogether, these results suggest that ML‐induced CD163 expression modulates the host cell phenotype to create a favorable environment for myco‐bacterial entry and survival.  相似文献   
84.
Cognitive and olfactory impairments have been demonstrated in patients with Machado–Joseph disease (MJD), and a possible relationship with dopaminergic dysfunction is implicated. However, there is still controversy regarding the pattern of striatal dopaminergic dysfunction in patients with MJD. In this study, we investigated whether these patients had different Dopamine Transporter (DAT) densities as compared to healthy subjects, and correlated these data with cognitive performance and sense of smell. Twenty-two MJD patients and 20 control subjects were enrolled. The neuropsychological assessment comprised the Spatial Span, Symbol Search, Picture Completion, Stroop Color Word Test, Trail Making Test and Phonemic Verbal Fluency test. The 16-item Sniffin' Sticks was used to evaluate odor identification. DAT imaging was performed using the SPECT radioligand [99mTc]-TRODAT-1, alongside with Magnetic Resonance imaging. Patients with MJD showed significantly lower DAT density in the caudate (1.34 ± 0.27 versus 2.02 ± 0.50, p < 0.001), posterior putamen (0.81 ± 0.32 versus 1.32 ± 0.34, p < 0.001) and anterior putamen (1.10 ± 0.31 versus 1.85 ± 0.45, p < 0.001) compared with healthy controls. The putamen/caudate ratio was also significantly lower in patients compared with controls (0.73 ± 0.038 versus 0.85 ± 0.032, p = 0.027). Even though we had only two patients with parkinsonism, we detected striatal dopaminergic deficits in those patients. No significant correlations were detected between DAT density and cognitive performance or Sniffin' Sticks scores. The data suggests that striatal dopamine deficit is not involved in cognitive or sense of smell deficits. This finding raises the possibility of extra-striatal dopamine and other neurotransmitter system involvement or of cerebellum neurodegeneration exerting a direct influence on cognitive and sensorial information processing in MJD.  相似文献   
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The effect of copper on ion content (Na(+), K(+), Ca(2+), and Cl(-)) was evaluated in isolated mantle gills of the marine clam Mesodesma mactroides. Clams were collected at the Mar Grosso Beach (S?o José do Norte, Rio Grande do Sul [RS], southern Brazil), cryoanesthetized, and had their mantles dissected. Mantle cells were isolated and incubated in a calcium-free phosphate solution without (control) or with Cu (CuCl(2)). Cells were exposed to Cu for 1 h (5 μM) or 3 h (2.5 and 5 μM). In cells incubated with 2.5 μM Cu, a significant decrease in intracellular Cl(-) content was observed. However, in cells incubated with 5.0 μM Cu, significant reductions in Na(+), K(+), and Cl(-) intracellular content were observed. Given the mechanisms involved in ion transport in mantle cells of the marine clam M. mactroides, the findings described here suggest that Cu exposure inhibits carbonic anhydrase and Na(+)/K(+) -ATPase activity. Also, it can be suggested that Cu is competing with Na(+) for the same mechanisms of ion transport in the cell membrane, such as the Na(+) channels and the Na(+)/K(+)/2Cl(-) cotransporter. Results from the present study also clearly indicate that processes involved in cellular anion regulation are more sensitive to Cu exposure than those associated with the cellular cation regulation. Characterization of sites for Cu accumulation and toxicity in aquatic animals is important for derivation of metal binding constants at the biotic ligand. Also, identification of the mechanism of metal toxicity is needed for modeling metal accumulation in the biotic ligand and its consequent toxicity. Therefore, the findings reported here are extremely valuable for the development of a biotic ligand model version for marine and estuarine waters.  相似文献   
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Objectives: To analyze the relationship between pharyngeal response time (PRT) and lateralization of brain lesions.

Methods: A Cross-sectional study. 73 videofluoroscopic swallow studies (VFSS)were conducted on patients after stroke The study subjects were divided into : group 1 (G1) consisting of 39 individuals with left cortical lesion and group 2 (G2) consisting of 34 individuals with right cortical lesions. The VFSS of G1 and G2 subjects were analyzed using puree (A) and liquid (B) consistencies, and were also subdivided into young adults and older persons. . The mean PRT was divided into times shorter and longer than 250 ms.

Results: No statistically significant difference was observed between G1 and G2 for the A and B consistencies, being obtained : G1 (A mean: 56.6 ms; B mean: 99.5 ms; A mean: 3627 ms; B mean: 1712 ms) and G2 (A mean: 79.6 ms; B mean: 110.7 ms; A mean: 2040 ms, B mean: 1529 ms), for PRT shorter (A:p = .673; B: p = 1.000) and longer (A: p = .435; B: p = .847) than 250 ms, respectively. No statistically significant difference was found regarding the variable age in the comparison between young and old adults for mean PRT according to the A and B consistencies in G1 (A: p = .260; B: p = .732) and G2 (A: p = .586; B: p = .104).

Conclusion: No relationship between PRT and lateralization of brain lesion was observed with respect to subject age and to the swallowing of different food consistencies.  相似文献   

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