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151.
Few studies have analyzed the effect of stretching after immobilization on the structural and biochemical properties of tendons. Here, the effect of stretching and immobilization on the proximal (p), intermediate (i), and distal (d) regions of the deep digital flexor tendon in rats was analyzed. The d region was subjected to compression and tension forces, the i region was subjected to compressive forces and the p region received tension forces. Rats were separated into five groups: GI--control for GII; GII--immobilized rats; GIII--control for GIV and GV groups; GIV--immobilized and stretched rats; and GV--immobilized rats which were allowed free cage activity. GII showed a higher molecular organization in the d and p regions as detected by measuring optical retardation, a lower concentration of hydroxyproline in the i region and a significant decrease in noncollagenous proteins found in the three regions of the tendon. Regarding the glycosaminoglycans, diminishing dermatan sulfate and the absence of chondroitin sulfate in the i region were observed in GII when compared to GI. However, in the same region of GIV, higher concentrations of chondroitin and dermatan sulfate were observed along with a strong metachromasy. An increase in hydroxyproline content in the i region and a higher molecular organization in the d and p regions were observed in GIV. Apparently, the active isoforms of metalloproteinase-2 also increased after stretching in all regions. These results suggest that stretching after immobilization contributed to the increase in molecular organization and to the synthesis of extracellular matrix components.  相似文献   
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The purpose of our study was to investigate the prognostic value of clinical and pathological, in particular glomerular and tubulointerstitial morphometric variables in idiopathic membranous nephropathy (IMN). We prospectively followed 60 Caucasian patients diagnosed with idiopathic membranous nephropathy for at least 2 years or until primary outcome (≥50% permanent decrease in estimated glomerular filtration rate or death). Glomerular and tubulointerstitial morphometric variables at the time of renal biopsy were analyzed with respect to this outcome. Univariate analysis revealed that significant negative prognostic factors for this outcome were higher cholesterol and smaller albumin concentrations, higher creatinine and maximal 24-h proteinuria, higher grade of nephroangiosclerosis, higher glomerular basement membrane thickness and glomerulopathy index, higher interstitial fibrosis and tubular atrophy percentage and higher injury score. In multivariate analysis, only the maximal 24-h proteinuria and interstitial fibrosis and tubular atrophy percentage were independent predictors of this outcome. The results suggest that morphometric analysis, mainly quantitative measurement of interstitial fibrosis and tubular atrophy percentage, injury score, glomerular basement membrane thickness and glomerulopathy index could be used as an additional method for risk stratification of patients with idiopathic membranous nephropathy.  相似文献   
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Essential fatty acids play a crucial role in the activity of several neurotransmission systems, especially in the monoaminergic systems involved in cognitive and motor aspects of behavior. The present study investigated whether essential fatty acid dietary restriction over two generations could differentially affect dopaminergic cell populations located in the substantia nigra rostro-dorso-medial (SNrm) or caudo-ventro-lateral (SNcv) regions which display distinct neurochemical profile and vulnerability to lesions under selected pathological conditions. Wistar rats were raised from conception on control or experimental diets containing adequate or reduced levels of linoleic and α-linolenic fatty acids, respectively. Stereological methods were used to estimate both the number and soma size of tyrosine hydroxylase (TH)-immunoreactive neurons in the SNrm and SNcv. TH protein levels were assessed with Western blots. Long-term treatment with the experimental diet modified the fatty acid profile of midbrain phospholipids and significantly decreased TH protein levels in the ventral midbrain (3 fold), the number of TH-positive cells in the SNrm (~20%) and the soma size of these neurons in both SNrm (~20%) and SNcv (~10%). The results demonstrate for the first time a differential sensitivity of two substantia nigra dopaminergic cell populations to unbalanced levels of essential fatty acids, indicating a higher vulnerability of SNrm to the harmful effects induced by docosahexaenoic acid brain deficiency.  相似文献   
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Amyloidosis is a clinical entity that results from deposition of an extracellular protein material that causes disruption in normal architecture and impairs function of multiple organs and tissues. Secondary amyloidosis (AA) is a rare but serious complication that occurs in the context of cancer, chronic inflammation and chronic infectious diseases, including inflammatory bowel disease, mainly long-standing Crohn's disease. Renal failure is the most common clinical presentation of AA, ranging from nephrotic syndrome and impaired renal function to renal failure, with a potential for high morbidity. The incidence of the association of secondary amyloidosis in patients with Crohn's disease has been reported to be 0.5%-8%. We present a case of a 39-year-old male patient diagnosed with Crohn's disease at age 21 and submitted to right hemicolectomy because of ileus 17 years before. Thereafter, he was treated with corticosteroids for 15 years and with azathioprine for a short period; in the last three years he was on therapy with mesalazine alone. He was hospitalized due to worsening clinical condition and re-evaluation of the underlying disease. Physical examination revealed marked peripheral edema in both lower extremities. Endoscopic and radiographic examinations confirmed the underlying disease activity. Laboratory tests showed an increase of inflammatory reactants, anemia, hypocalcemia, and severe hypoalbuminemia and hypoproteinemia. He had proteinuria over 24 g/L and creatinine clearance of 66 mL/min, falling within second grade of chronic kidney disease. Renal biopsy was performed for evaluation of renal insufficiency with nephrotic range proteinuria. Congo red staining showed the presence of characteristic amyloid deposition; deposits immunoreacted with the antibody against amyloid A protein, confirming the diagnosis of secondary amyloidosis. The patient was suggested active induction treatment with corticosteroids and azathioprine to achieve remission of Crohn's disease, thereafter treatment with infliximab, but he did not consent with this therapy at that time. Studies with infliximab have demonstrated a decrease in SAA circulating levels and proteinuria, as well as stabilization of renal function. Amyloidosis is frequently described as a major cause of death in patients with Crohn's disease, with long-term mortality between 40% and 60%. Various therapeutic attempts such as azathioprine, colchicine, dimethyl sulfoxide, infliximab, and elemental diets have been tried but there is no definite treatment for secondary amyloidosis in Crohn's disease. Kidney transplantation may offer the best prospects for patients with Crohn's disease who develop amyloidosis and end-stage renal failure.  相似文献   
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Abstract: Introduction: Kidney transplantation is currently the treatment of choice for end‐stage renal disease. As the successful transplantation improves the physical and mental quality of life, it is expected that the transplant recipient should play a productive role in the society. The present study evaluates the occurrence and predictors of employment after kidney transplantation. Methods: Population‐based cross‐sectional study in which 272 adult kidney recipients assisted in a Brazilian Southern state were evaluated. Results: At the moment of the interview, 29% of the patients were employed. After analysis with logistic regression, the predictors of employment were male sex (OR 4.04; 95% CI 1.99–8.23), pre‐transplant employment for non‐diabetic (OR 4.35; 95% CI 3.79–4.99), diabetes for individuals who worked while on dialysis (OR 0.06; 95% CI 0.008–0.5), high educational level for individuals with mental quality of life scores above the 25th percentile (OR 3.06; 95% CI 2.98–3.14 for 50th percentile of mental quality of life). The Hosmer–Lemeshow test was of 3.33 (p = 0.91). Conclusion: The participation of the kidney transplant recipients with functioning graft into the work force in the Brazilian state of Rio Grande do Sul is low, being predicted mainly by sociodemographic factors. It was not detected any influence of patient perception of his/her physical conditions or other clinical variables, except for the presence of diabetes.  相似文献   
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