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31.
The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.  相似文献   
32.
L-carnitine is a quaternary amine that is essential for the normal oxidation of long-chain fatty acids by mitochondria. It is known that L-carnitine and its derivatives prevent the formation of reactive oxygen species, scavenge free radicals and protect cells from peroxidative stress. Oxygen-derived free radicals and lipid peroxidation products play a critical role in the pathogenesis of ethanol-induced gastric mucosal injury. The aim of the present study was to determine the effect of L-carnitine on lipid peroxidation induced by ethanol in the rat stomach. In our study, gastric mucosal injury was induced by the intragastric administration of 1 ml of absolute ethanol. Test compounds were given to rats by gavage 30 min before the ethanol administration. The animals were killed 60 min after the administration of ethanol. The stomach of each animal was removed. Mucosal damage was evaluated by macroscopic examination, histological analysis and by measurement of lipid peroxidation and glutathione activity. The intragastric administration of ethanol induced hyperemia and hemorrhagic erosions in the rat stomachs. L-carnitine significantly prevented gastric ulcerogenesis induced by ethanol and decreased the ulcer index. Plasma and gastric lipid peroxidation that was increased significantly by ethanol was decreased after treatment with L-carnitine. Ethanol treatment decreased significantly the gastric glutathione levels, and pretreatment with L-carnitine increased them significantly. Based on these data, the beneficial effects of L-carnitine on ethanol-induced gastric mucosal injury may be attributed to its antiperoxidative effects.  相似文献   
33.
We have studied the effects of three antioxidants and amrinone, an inotropic agent, against vancomycin-induced nephrotoxicity in rats by investigating renal function and morphology. Thirty adult female Sprague Dawley rats (168-234 g) were divided into six groups. A saline-treated group served as control. The other five groups were treated for 7 days with vancomycin alone or in combination with alpha-lipoic acid, Ginkgo biloba extract 761, melatonin or amrinone. On day 8, all the rats were sacrificed by decapitation, kidney tissues were excised immediately and blood and kidney samples were collected. Blood urea and creatinine, kidney tissue malondialdehyde levels, and kidney superoxide dismutase and glutathione (GSH) peroxidase activities were measured. The kidneys were also examined for histological changes. Vancomycin administration led to increased urea, creatinine and malondialdehyde levels and decreased superoxide dismutase and GSH peroxidase activities. Co-administration of alpha-lipoic acid, Ginkgo biloba extract, melatonin or amrinone with vancomycin prevented the increases in the urea, creatinine and melondialdehyde levels and also resulted in higher superoxide dismutase and GSH peroxidase activities. The antioxidants and AMR improved the renal pathology compared to rats treated with vancomycin alone (P<0.05). These results indicate that the three antioxidants and amrinone have potential protective effects against vancomycin-induced nephrotoxicity, which might in part be due to inhibition of free oxygen radical production. Amrinone was the most effective drug as judged on the basis of the pathological findings.  相似文献   
34.
Bone mineral status has extensively been investigated in adult thalassemics but less in thalassemic children. This study involves measurements of the bone mineral density (BMD), various demographic and biochemical parameters in 47 thalassemic children and 50 healthy controls with comparable age, sex, socioeconomic and regional distribution. Patients have significantly higher aspartate aminotransferase, alanine aminotransferase, phosphorous, osteocalcin, serum carboxy terminal teleopeptide fragment of type I collagen, intact parathyroid hormone (iPTH) and ferritin levels while they have significantly lower 25-hydroxy vitamin D (25OH-D), alkaline phosphatase and z-scores both at lumbar and femur compared to controls. Patients with high iPTH (30%) had significantly lower z-scores and 25OH-D while larger osteocalcin. We conclude that a significantly lower BMD in beta-thalassemic children compared with their healthy counterparts is a complex process and may partially attributed to their slower physical development, caused by iron overload and chelation therapy which may influence the liver as well as the endocrine tissues.  相似文献   
35.
Inferior turbinate hypertrophy is a frequent cause of nasal airway obstruction and drastically impairs patients’ quality of life. Surgical reduction of the inferior turbinates can be used for patients who did not respond to medical therapy. A number of studies have been performed to identify the most effective technique. The aim of this study was to compare the effectiveness of submucosal resection (SMR) and radiofrequency turbinate volume reduction (RFTVR) in patients with inferior turbinate hypertrophy. A prospective, randomized case–control study was conducted. Sixty patients with inferior turbinate hypertrophy refractory to medical therapy were prospectively and randomly assigned to two groups: SMR and RFTVR. A visual analog scale (VAS) and the nasal inspiratory peak flow (NPIF) were analyzed pre- and postoperatively at the first week and second month. Magnetic resonance imaging was performed pre- and postoperatively at the second month. The surgical outcomes were compared statistically using subjective and objective measures. Significant turbinate volume reduction was achieved in both the SMR and RFTVR groups. However, turbinate volume reduction was significantly greater in the SMR than in the RFTVR group at the second month postoperatively. NIPF and VAS scores were improved after both procedures at the second month postoperatively. Beside this, surgical outcomes were significantly better after SMR in terms of NIPF and VAS scores. In this study, we demonstrated that both SMR and RFTVR are effective for inferior turbinate hypertrophy. Turbinate volume reduction, improvement of subjective nasal obstruction symptoms, and NIPF after SMR were significantly superior to those after RFTVR.  相似文献   
36.
The aim of this study was to assess the relation between silver-strained nucleolar organizer regions (AgNOR), tumor stage, tumor grade and p53 expression with cathepsin B staining in transitional cell carcinoma of bladder. Tissue sections from 64 transitional cell carcinomas of the bladder were evaluated for the relation between AgNOR, tumor stage, tumor grade and p53 expression with cathepsin B staining in the neoplastic and stromal cells. Mean AgNOR values were significantly higher and the presence of p53 expression were different in cathepsin B positive and negative tumor and stromal cells. Although the number of cases is limited, this pilot study shows that cathepsin B staining may have a prognostic value in transitional cell carcinoma, but more studies are needed for a definite conclusion.  相似文献   
37.
AIMS: To investigate the value of alpha-smooth muscle actin (alpha-SMA), an indicator of stellate cell activation, in predicting fibrosis in chronic hepatitis B (CHB) patients. METHODS AND RESULTS: The liver biopsy specimens of 30 patients with a clinical diagnosis of CHB were obtained before treatment and scored by Knodell's histological activity index. The specimens were then immunohistochemically stained with alpha-SMA and semiquantitatively evaluated. Fibrosis and the immunoreactivity of alpha-SMA in the periportal, perisinusoidal and pericentral areas were compared. Fibrosis and necroinflammatory activity in CHB patients were significantly correlated (P =0.022). Furthermore, the degree of alpha-SMA expression and the scores of fibrosis (in periportal, perisinusoidal and pericentral areas) were highly correlated (P =0.000, 0.001, 0.000, respectively). CONCLUSIONS: In liver biopsy samples, alpha-SMA may prove to be a valuable marker in the evaluation of stellate cell activation and fibrosis progression and an early indicator of the development of fibrosis.  相似文献   
38.
Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent inflammatory febrile attacks, abdominal, chest or joint pain, myalgia, and erysipelas-like skin lesions. Several types of vasculitis are associated with FMF such as polyarteritis nodosa and Henoch–Schönlein purpura. We aimed to determine microvascular abnormalities in FMF patients via nailfold capillaroscopy using a dermoscope. Thirty-one FMF patients were assessed; capillary enlargement, tortuosity, avascular areas and microhemmoraghes were investigated. Capillary enlargement was found in five patients and microhemorrhages in one patient. Our study supports that nailfold capillary abnormalities, which are nonspecific, can be seen in FMF patients, but more studies are needed to clarify the importance of these findings.  相似文献   
39.
To determine the diagnostic significance of the kappa/lambda ratio in germinal center (GC) B cells in Hashimoto thyroiditis (HT), we used 4-color flow cytometry to immunophenotype 27 samples (21 patients) of well-characterized HT B-cell clonality was analyzed further by polymerase chain reaction (PCR) of the immunoglobulin heavy chain (IgH) and bcl-2/IgH fusion genes using DNA extracted from aspirate smears and/or paraffin-embedded tissues. By flow cytometric analysis, the CD10+ GC B cells had a higher mean +/- SD kappa/lambda ratio than the CD10- B cells (5.1 +/- 3.3 vs 2.0 +/- 0.8; P < .0001, Student t test). In 18 samples (67%), CD10+ GC B cells had a kappa/lambda ratio greater than 3.07 (the upper limit of kappa/lambda ratio reported in reactive nodes; range, 3.2-14.4 in the 18 cases). Cases tested by PCR showed no evidence of a clonal proliferation. None of 21 cases developed lymphoma during clinical follow-up of up to 3 years. The kappa/lambda ratio of CD10+ GC B cells in HT can be skewed markedly beyond that reported in reactive lymph nodes. This finding frequently is present in HT. Pathologists should be familiar with this phenomenon to prevent misdiagnosis of follicular lymphoma in patients with HT.  相似文献   
40.
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