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61.
OBJECTIVE: To investigate the role of aqueous garlic extract (AGE) on the water-avoidance stress (WAS)-induced degeneration of the urinary bladder in a rat model. MATERIALS AND METHODS: Wistar albino rats were exposed to WAS for 2 h/day for 5 days (WAS group), after which, AGE (1 mL/kg) was injected intraperitoneally into the rats (WAS + AGE group). Urinary bladder samples were investigated with both light and scanning electron microscopy, and lipid peroxidation and glutathione levels were also measured in the samples. RESULTS: In the WAS group there was inflammatory cell infiltration, more mast cells and ulcerated areas in the mucosa. In the WAS + AGE group there was relatively normal urothelial alignment, moderate inflammatory cell infiltration and fewer mast cells in the mucosa. The increased lipid peroxidation and decreased glutathione levels in WAS rats were reversed by AGE treatment. CONCLUSIONS: These results show that AGE has a protective effect on WAS-induced degenerative changes in the urinary bladder.  相似文献   
62.
The efficacy of methotrexate (MTX), a widely used cytotoxic chemotherapeutic agent, is often limited by severe side effects and toxic sequelae. Regarding the mechanisms of these side effects, several hypotheses have been put forward, among which oxidative stress is noticeable. The present study was undertaken to determine whether taurine, a potent free radical scavenger, could ameliorate MTX-induced oxidative injury and modulate immune response. Following a single dose of methotrexate (20 mg/kg), either saline or taurine (50 mg/kg) was administered for 5 days. After decapitation of the rats, trunk blood was obtained and the ileum, liver, and kidney were removed to measure malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and collagen content, as well as histological examination. Our results showed that MTX administration increased the MDA, MPO activity, and collagen contents and decreased GSH levels in all tissues (P < 0.001), while these alterations were reversed in taurine-treated group (P < 0.05-0.01). Elevated (P < 0.001) TNF-alpha level observed following MTX treatment was depressed with taurine (P < 0.01). Oxidative burst of neutrophils stimulated by phorbol myristate acetate was reduced in saline-treated MTX group (P < 0.001), while taurine abolished this effect. Similarly, flow cytometric measurements revealed that leukocyte apoptosis and cell death were increased in MTX-treated animals, while taurine reversed these effects (P < 0.05). Reduced cellularity in bone marrow samples of MTX-treated group (P < 0.01) was reversed back to control levels in taurine-treated rats. Severe degeneration of the intestinal mucosa, liver parenchyma, glomerular, and tubular epithelium observed in saline-treated group was improved by taurine treatment. In conclusion, it appears that taurine protects against methotrexate-induced oxidant organ injury and inhibits leukocyte apoptosis and may be of therapeutic potential in alleviating the systemic side effects of chemotherapeutics.  相似文献   
63.
Nontraumatic psychological water avoidance stress has been shown to induce mucosal degeneration, inflammatory cell infiltration and mast cell degranulation in stomach, ileum, colon and urinary bladder. Many skin disorders, such as atopic dermatitis and psoriasis, worsen during stress and seem to be related with infiltration and activation of mast cells releasing vasoactive and proinflammatory mediators. Melatonin is a free radical scavenger and has cytoprotective effects in inflammatory conditions. The aim of the present study was to investigate the effects of melatonin on water avoidance stress (WAS)-induced degranulation of mast cells in the dermis. Wistar rats were exposed to acute WAS (aWAS group) or chronic WAS (cWAS group). Before exposing to acute WAS, one group of animals was treated with 10 mg/kg melatonin (aWAS+mel group). In the cWAS+mel group, treatment with melatonin lasted for 5 days. Dermal mast cells were stained with toluidine blue and investigated using light microscopy. Numbers of mast cells were increased in both aWAS and cWAS groups, but numbers of degranulated mast cells were increased significantly only in the cWAS group when compared to the control group. Numbers of mature granulated and degranulated mast cells were decreased in the cWAS+mel group when compared to the cWAS group. In conclusion, chronic melatonin treatment reduced WAS-induced infiltration and activation of mast cells in dermis and may provide a useful therapeutic option in stress-induced skin disorders.  相似文献   
64.
BACKGROUND: The present study was conducted to determine the possible effect of naproxen sodium on clinical status and the enzymatic profile of gingival crevicular fluid (GCF) when given as adjunct to periodontal treatment. METHODS: A total of 34 subjects with chronic periodontitis were selected and divided into two groups to receive either naproxen sodium or placebo. At baseline, GCF samples were obtained and probing depths (PD), gingival index (GI), plaque index (PI), and gingival bleeding index (GBI) scores were recorded. In the non-steroidal anti-inflammatory drug (NSAID) group, patients were treated with a protocol consisting of baseline periodontal treatment (scaling, root planing) and naproxen sodium (275 mg) administration daily for 6 weeks. In the placebo group, patients received the same treatment except placebo was given instead of naproxen sodium. At the end of the experimental period, clinical recordings and GCF sampling were repeated. Myeloperoxidase (MPO) and elastase-like enzyme activity (ELA) levels were determined in GCF samples by a spectrophotometric method. GCF enzymatic content was calculated both as total enzyme activity and enzyme concentration. RESULTS: All of the clinical parameters, except mean GBI, were significantly lower in the experimental group (P <0.05). At baseline and at the end of the experimental period, there were no significant differences between the NSAID and placebo groups regarding GCF MPO and ELA levels in either mode of data presentation (P <0.05). However, in the NSAID group, mean ELA concentration (P = 0.002) and mean total ELA (P = 0.003) presented significant decreases with treatment. Also, with treatment, a general reduction in MPO levels was seen; however, this difference was not significant. Although constant and stable correlations between GCF enzyme levels and clinical parameters could not be found, positive and strong correlations were observed between total enzyme activity and enzyme concentrations. CONCLUSION: Based on the positive clinical effect and the ELA profile of GCF, it can be suggested that NSAIDs given as an adjunct to baseline periodontal treatment could be beneficial in the outcome of treatment.  相似文献   
65.
BACKGROUND: The aim of the present study was to determine the effect of a chlorhexidine chip on crevicular prostaglandin E2 (PGE2) levels and on the clinical and microbiological parameters of periodontitis when used as adjunctive therapy to scaling and root planing (SRP) in patients with chronic periodontitis. METHODS: This randomized single-blind study was carried out in parallel design. The test group received SRP plus chlorhexidine chip, whereas the control group received SRP alone. Thirty-four subjects, aged 20 to 55 years, with chronic periodontitis were recruited. Clinical indices, microbiological samples, and gingival crevicular fluid (GCF) samples were evaluated at baseline and after 1, 3, and 6 months. Microbiological samples were evaluated under a light microscope. GCF PGE2 levels were determined using radioimmunoassay. RESULTS: Significant improvements could be found for all clinical variables in both groups over the study period. The mean changes in probing depth obtained by SRP plus chlorhexidine chip were greater than those obtained by the SRP alone group at 3 and 6 months. In the test group, there was also significant gain in clinical attachment level at 6 months. When data were combined from all groups, significant reductions in GCF PGE2 levels and number of microorganisms were noted at all time points. However, in the test group, reduction was greater at 6 months for crevicular PGE2 level and at 3 and 6 months for proportions of spirochetes. CONCLUSION: Based on the findings of this study, the chlorhexidine chip reduced GCF PGE2 levels and had positive effects on clinical parameters and subgingival flora when used as adjunctive therapy to SRP in patients with chronic periodontitis.  相似文献   
66.
IntroductionChanges in sex hormone levels may play a role in the etiology of lower urinary tract dysfunction of aging women where the possible role of testosterone is overlooked.AimTo determine the effect of testosterone with/without estrogen replacement on histological and functional deterioration in ovariectomized rat bladder tissue.MethodsA total of 54 female Sprague Dawley rats were divided into 6 groups. Except sham operated (control group), all others underwent bilateral ovariectomy. No further treatment was given to the ovariectomy-only group (OVX group). At the third week of ovariectomy treatments were started; vehicle agent (VA group), estradiol (E2 group), testosterone undecanoate (T group), and estradiol + testosterone undecanoate combination (E2 + T group) in physiological doses. Nine weeks after ovariectomy, bladder strips were harvested for isometric tension and histopathological studies.Main Outcome MeasuresTo assess the effect of testosterone/estradiol on ovariectomized rat bladder tissue function and histomorphology.ResultsOVX and VA groups showed statistically significant histological changes such as urothelial damage, inflammatory cell infiltration, increase in collagen fibers and muscular atrophy compared with the control group. Both E2 and T reversed these changes but best histomorphological restoration was observed in E2 + T group. In isometric tension studies, ovariectomy tended to increase contractile responses which were normalized after E2 treatment. In contrary to E2, T significantly increased contractile responses that were normalized with combination treatment. During relaxation studies statistically significant higher relaxation responses were observed in ovariectomized rats. Although both exogenous testosterone and estradiol tended to reverse this effect, a statistically significant difference was found only after testosterone treatment.ConclusionEither estradiol or testosterone replacement alone or in combination prevents significant alterations in bladder tissue histology following ovariectomy whereas both affect the bladder tissue contractility. Thus, combination treatment appears to be the best method to restore both contractility and histomorphology of bladder tissue after ovariectomy. Tanidir Y, Ercan F, and Tarcan T. Exogenous testosterone and estrogen affect bladder tissue contractility and histomorphology differently in rat ovariectomy model.  相似文献   
67.
OBJECTIVES: REM sleep behavior disorder (RBD) has been documented to precede or to co-occur with Parkinson's disease (PD). Parkinson's disease is one of the most common neurological conditions associated with visual hallucinations. Cognitive dysfunction is present in PD, even at the early stages of these diseases. In this study we aimed to investigate the relationship between visual hallucinations and RBD in patients with idiopathic Parkinson's disease (IPD). Additionally, we evaluated the association of the cognition and the pattern of cognitive impairment with VHs and RBD, effects of factors like duration and severity of the disease and duration of levodopa usage. PATIENTS AND METHODS: Seventy-nine patients, diagnosed as PD, were included the study and then, patients were divided into four groups; with RBD and VHs (group 1), with RBD but no VHs (group 2), with VHs but no RBD (group 3), without RBD and VHs (group 4). We compared each group with the others according to demographic characteristics and neuropsychological test scores. RESULTS: Of all patients, in 46% (n=36) RBD and in 48% (n=38) VHs were observed. Our study established VHs in 58% of patients with RBD, and RBD in 55% of patients with VHs. However, due to a 40% incidence of VHs in patients without RBD, RBD and VHs were not found to be correlated. All of the neuropsychometric test scores did not reveal significant difference between groups. CONCLUSION: Although it seems like there is a small association between RBD and VHs in our patients, it was not significant. Group 1 presented with significantly worse scores in UPDRS total scores and I, II subscores.  相似文献   
68.
BACKGROUND: Sepsis is associated with enhanced generation of reactive oxygen species, which leads to multiple organ dysfunctions. Based on the potent antioxidant effects of silymarin, we investigated the putative protective role of silymarin against sepsis-induced oxidative damage in lung and brain tissues. MATERIALS AND METHODS: Sepsis was induced by cecal ligation and perforation (CLP). Sham and CLP groups received either vehicle or silymarin (50 mg/kg, p.o.) or 150 mg/kg i.p. N-acetylcysteine (NAC) for 10 days prior and immediately after the operation. Six hours after the surgery, rats were decapitated and blood was collected for the measurement of proinflammatory cytokines (tumor necrosis factor-alpha, interleukin-1 beta [IL-1 beta], and IL-6) levels, lactate dehydrogenase activity, and total antioxidant capacity. Lung and brain samples were taken for the measurement of malondialdehyde and glutathione levels, myeloperoxidase activity, thromboplastic activity, and also for histological assessment. Formation of reactive oxygen species in tissue samples was monitored by using chemiluminescence technique with luminol and lusigenin probe. RESULTS: Sepsis increased serum TNF-alpha, IL-1 beta, IL-6 levels, and lactate dehydrogenase activity and decreased total antioxidant capacity. On the other hand, tissue glutathione levels were decreased while malondialdehyde levels and myeloperoxidase activity were increased in both the lung and the brain tissues due to CLP. Furthermore, luminol and lucigenin chemiluminescence were significantly increased in the CLP group, indicating the presence of the oxidative damage. Silymarine and NAC treatment reversed these biochemical parameters and preserved tissue morphology as evidenced by histological evaluation. CONCLUSIONS: Silymarin, like NAC, reduced sepsis-induced remote organ injury, at least in part, through its ability to balance oxidant-antioxidant status, to inhibit neutrophil infiltration, and to regulate the release of inflammatory mediators.  相似文献   
69.
70.
The thyroid gland is an endocrine organ composed of stable cells. It is well known that regenerative capacity of the thyroid tissue is minimal. Various degrees of morphologic alterations do occur in chronic lymphocytic thyroiditis (CLT), including Hashimoto's thyroiditis. Eighty-five CLT cases were analyzed for these morphologic alterations. Small, irregular, atrophic or hyperplastic thyroid follicles were seen adjacent to the lymphocytic infiltration. There was nuclear enlargement, loss of nuclear polarity in thyrocytes and intrafollicular thyrocyte proliferation in these follicles. We thought that the morphologic alterations in involved follicles could be due to regenerative hyperplasia with increased proliferative activity and basement membrane abnormalities. To examine this hypothesis we investigated Ki-67 and laminin immunoreactivity in the involved follicles adjacent to lymphocytic infiltration areas. The uninvolved follicles were used as controls. Immunopositivity of Ki-67 in involved follicles was significantly higher than that in uninvolved follicles (2.97% +/- 2.16 versus 0.83% +/- 1.63, P < 0.001). Laminin immunostaining indicated the destruction or irregular distribution of basement membrane in involved follicles. We conclude that the increased cell proliferation activity and basement membrane abnormalities in the follicles with morphologic changes adjacent to CLT occur in conjunction with regenerative hyperplasia.  相似文献   
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