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91.
The objective of this study was to determine the prevalence of Hepatitis C virus (HCV) in adults from Criciuma-SC and to search factors associated with the viral transmission. METHODS: During a health campaign, a questionnaire about factors associated to HCV transmission and tests to detect HCV were applied. A representative sample of the population was considered with 300 voluntaries. Fisher's Exact test, Mann-Whitney and Kappa tests were performed (p values < 0.05 were considered significant). RESULTS: HCV was detected in 7/ 457 (1.53 %) voluntaries. Subjects with positive HCV had a mean of 5.7 (+/- 4.1 SD) sexual partners in the last 10 years, which was significantly higher than those with negative anti-HCV (mean sexual partners 2 +/- 2.5 SD) (p= 0.01). CONCLUSION: The prevalence of HCV in a voluntary population of adults from Criciuma-SC was high and there was significant association between positive anti-HCV and higher number of sexual partners.  相似文献   
92.
BACKGROUND: Graft coronary artery vasculopathy is the main cause of late morbidity and mortality in pediatric cardiac allograft recipients. Growing evidence suggests that elevated plasma homocysteine levels are associated with cardiac allograft vasculopathy following heart transplantation. The purpose of this study was to evaluate the effect of vitamin supplementation as a potential strategy for reducing homocysteine levels in pediatric heart transplant recipients and examine creatinine levels as potential determinants of plasma homocysteine concentration after transplantation. METHODS: We studied 27 pediatric heart transplant patients with homocysteine levels higher than normal. All children received vitamin supplementation (vitamin B(12), vitamin E, vitamin A and folic acid). During treatment, levels of homocysteine, vitamins and creatinine were evaluated after 3, 6, 9 and 12 months. RESULTS: We observed a significant homocysteine concentration decrease after treatment at every determination, whereas no significant change occurred for creatinine. Vitamin B(12) serum level increased markedly, whereas folic acid, vitamin E and vitamin A serum levels showed only minor increases. CONCLUSIONS: We observed a significant increase of mean levels of vitamin B(12) and a moderate increase in the other 3 vitamins. We also observed a significant reduction in homocysteine levels, which returned to normal levels for age. In our patients, there was a correlation, before and after treatment, between homocysteine and creatinine levels, but there was no a direct correlation between creatinine serum levels and homocysteine reduction. We conclude that vitamin supplementation reduces and may normalize homocysteine serum level after pediatric heart transplantation.  相似文献   
93.
Both ATP and acetylcholine can induce the mobilization of intracellular calcium in the early developing chick embryo retina, a response that decreases during retinal development. In this study, the effects of these transmitters on the turnover of phosphoinositides and proliferation of developing retinal cells in culture were characterized. While ATP, UTP or carbachol were able to induce a >400% accumulation of phosphoinositides in retinal cell cultures, only ATP promoted a dose-dependent increase in [(3)H]-thymidine incorporation in cultured cells (EC(50)=8.6 microM), a response that was inhibited by the P2 receptor antagonist pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (PPADS) (0.1 or 0.25 mM). ADP, but not UTP or adenosine, also stimulated the proliferation of retinal cells (EC(50)=5.8 microM), indicating that activation of P2Y1 receptors mediates the proliferative response of retinal cells to ATP. The mitogenic effect of ATP was completely prevented by the PKC inhibitor chelerythrine chloride (0.5 microM) and the phospholipase C (PLC) inhibitor U73122 (0.5 microM). PD 98059 (25 or 50 microM), an inhibitor of the activation of extracellular signal-regulated kinases (ERKs) also blocked the increase in [(3)H]-thymidine incorporation induced by ATP. Moreover, the effect of ATP was pronounced in cultures obtained from retinas at embryonic days 6-8, but not at day 9. Since Müller and bipolar cells are the predominant cell types that proliferate at these embryonic stages, our data suggest that ATP, through activation of P2Y1 receptors coupled to phospholipase C, PKC and MAP kinases, affects DNA synthesis in one or both of these cell types in culture.  相似文献   
94.

Background

The Walking Estimated-Limitation Calculated by History (WELCH) questionnaire has been proposed to evaluate walking impairment in patients with intermittent claudication (IC), presenting satisfactory psychometric properties. However, a Brazilian Portuguese version of the questionnaire is unavailable, limiting its application in Brazilian patients.

Objective

To analyze the psychometric properties of a translated Brazilian Portuguese version of the WELCH in Brazilian patients with IC.

Methods

Eighty-four patients with IC participated in the study. After translation and back-translation, carried out by two independent translators, the concurrent validity of the WELCH was analyzed by correlating the questionnaire scores with the walking capacity assessed with the Gardner treadmill test. To determine the reliability of the WELCH, internal consistency and test-retest reliability with a seven-day interval between the two questionnaire applications were calculated.

Results

There were significant correlations between the WELCH score and the claudication onset distance (r = 0.64, p = 0.01) and total walking distance (r = 0.61, p = 0.01). The internal consistency was 0.84 and the intraclass correlation coefficient between questionnaire evaluations was 0.84. There were no differences in WELCH scores between the two questionnaire applications.

Conclusion

The Brazilian Portuguese version of the WELCH presents adequate validity and reliability indicators, which support its application to Brazilian patients with IC.  相似文献   
95.

Statement of problem

Nonthermal argon plasma may increase the surface energy of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) dental ceramics. However, studies that evaluated the effect of increased plasma treatment times on the bond strength of resin cements to Y-TZP ceramics are lacking.

Purpose

The purpose of this in vitro study was to evaluate the effect of different nonthermal argon plasma (NTAP) treatment times on the surface energy and bond strength of a self-adhesive resin cement to Y-TZP ceramic.

Material and methods

Forty-eighty Y-TZP plates were divided into 2 groups (n=24): as-sintered (AS) and airborne-particle abrasion (APA) with 50-μm Al2O3, which were subdivided into 4 groups (n=6) according to the time of NTAP treatment: 0, 20, 60, and 120 seconds. The surface energy was evaluated with a goniometer. Forty Y-TZP blocks submitted to the same surface treatments (8 groups; n=5) were cemented to composite resin blocks, using a self-adhesive resin cement. After storage in distilled water at 37°C for 24 hours, the Y-TZP-composite resin blocks were cut into beams and submitted to a microtensile bond strength (μTBS) test. Data were analyzed using 2-way ANOVA and the Tukey honestly significant differences test (α=.05).

Results

Treatment with NTAP increased the surface energy for AS and APA groups (P<.05). For both groups, the μTBS was as follows: 0 seconds < 20 seconds < 60 seconds = 120 seconds (P<.05). Only after 120 seconds of NTAP treatment was the μTBS of APA higher than that of AS (P<.05).

Conclusions

Treatment with NTAP improved the surface energy and increased the μTBS of self-adhesive resin cement to Y-TZP ceramic, with higher times of plasma treatment resulting in higher bond strength.  相似文献   
96.
97.
Fusarium verticillioides is a primary corn pathogen and one of the main producers of fumonisins, a group of mycotoxins that cause several diseases in animals and probably also affect humans. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) based on polyclonal antibodies was developed to detect the exoantigen of this fungus in corn and its correlation with traditional methods for mould detection was evaluated. Forty freshly harvested corn samples were analysed for F. verticillioides exoantigens, as well as for total mould count, ergosterol and fumonisin levels in order to evaluate the relationship between these parameters. In addition, F. verticillioides was grown in brain heart infusion (BHI) broth in order to evaluate the correlation between biomass and exoantigen concentration. There was no significant correlation between exoantigen concentration and total mould count, Fusarium sp. count and fumonisin levels. The correlation coefficient between exoantigens and ergosterol content was 0.52 and between biomass and F. verticillioides exoantigens in BHI broth was 0.84. These results suggest that this ic-ELISA has potential for Fusarium sp. detection in corn samples.  相似文献   
98.
Attempts to identify an early and discriminating marker of acute graft-versus-host disease (aGvHD) have been unsuccessful. The levels of soluble CD4 and soluble CD8 in serum correlate with T cell subset activation and may be important in monitoring and characterizing immunological processes. We determined serum soluble CD4 (sCD4) and sCD8 levels with a two-site sandwich enzyme immunoassay on patients' serum samples collected prior to bone marrow transplantation and weekly after transplantation until day +28. No significant increment of sCD4 was documented in each determination. sCD8 rose significantly before diagnosis or development of maximal clinical symptoms in patients with grade II–III aGvHD than grade 0–I aGvHD [at day +21—median value 447 IU/ml; range 94–713; versus 1136 IU/ml, range 790–1416P=0.002); at day +28—median value 443 IU/ml, range 73–992, versus 1164 IU/ml, range 625–1960P=0.005)]. On the day of marrow infusion the sCD8 levels were significantly higher in patients who subsequently developed grade II–III than in patients with grade 0–I aGvHD (median value 155 IU/ml, range 10–332, versus 350 IU/ml, range 283–830;P=0.003). Careful monitoring of sCD8 is a useful tool for a prompt aGvHD diagnosis and may be used in a clinical bone marrow transplantation setting.  相似文献   
99.
BACKGROUND: BIOSA is a single sheet, two-cuspal-shaped ("bileaflet") glutaraldehyde fixed bovine pericardial valve prosthesis (BP), designed to minimize stress and prevent mechanical failure. We tested this device in the adult sheep model. METHODS: Seven BIOSA and two Baxter Carpentier-Edwards (Perimount) pericardial BPs, 25 mm in size, were implanted in the tricuspid position of adult sheep. A mid term BIOSA explant (81 days) died of infective endocarditis. The remaining BPs were divided in three early explants (0-3 days: two BIOSA and one Perimount) and five late explants (162-189 days: four BIOSA and one Perimount). Protocol of the study included gross examination, mammography X-ray (score 0-4), histology, scanning (SEM) and transmission (TEM) electron microscopy and atomic absorption spectroscopy. RESULTS: (a) Early explants: The mesothelium was detached, collagen-elastic fibers and pericardiocytes of the fibrosa showed optimal preservation. Calcium content in BIOSA BPs was 6.22 mg/g dry weight (mean) versus 7.75 mg/g of the Perimount BP. (b) Late explants: At naked eye all BPs showed regular cusp pliability and coaptation, without tears, perforations, fibrous pannus or calcific deposits. X-ray was either negative (three BPs) or exhibited score 1 (two BPs). Microscopic features were excellent both in terms of collagen-elastic fibers preservation and absence of inflammation. The calcium content was 4.95 mg/g dry weight (mean) in BIOSA BPs versus 5.29 mg/g in the Perimount BP. CONCLUSIONS: Tissue characteristics of BIOSA BPs were optimal, without difference with Perimount BPs and in this animal model no case of structural valve deterioration occurred in the long term.  相似文献   
100.
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