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Background and Aim:  The aim of this study was to determine whether resveratrol could prevent intestinal tissue injury induced by ischemia–reperfusion (I/R).
Methods:  Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results:  The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P  < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P  < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P  < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions:  The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models.  相似文献   
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Vasodilating mechanisms of testosterone.   总被引:2,自引:0,他引:2  
The increased incidence of cardiovascular disease in man compared with premenopausal women suggests an unfavourable effect of male sex hormone testosterone on the cardiovascular system. However, numerous clinical and epidemiological studies reported a controversial relationship between testosterone and cardiovascular disease. Furthermore, an increasing amount of evidence indicate that testosterone can exert acute vasorelaxing effects, VIA non-genomic mechanisms. These effects involve primarily the vascular smooth muscle, without requiring the presence of endothelium, although an endothelial contribution is apparent in some studies. To date, the mechanism behind the vasodilatory action of testosterone is still under debate and might be through either activation of K (+) channels or blockade of Ca (2+) channels in vascular muscle cells. The purpose of this article is to review the evidence regarding the vasodilating effect of testosterone as well as its mechanism of action.  相似文献   
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Measles virus (MV) constitutes a principal cause of worldwide mortality, accounting for almost 1 million deaths annually. Although a live-attenuated vaccine protects against MV, vaccination efficiency of young infants is low because of interference by maternal antibodies. Parental concerns about vaccination safety further contribute to waning herd immunity in developed countries, resulting in recent MV outbreaks. The development of novel antivirals that close the vaccination gap in infants and silence viral outbreaks is thus highly desirable. We previously identified a microdomain in the MV fusion protein (F protein) that is structurally conserved in the paramyxovirus family and constitutes a promising target site for rationally designed antivirals. Here we report the template-based development of a small-molecule MV inhibitor, providing proof-of-concept for our approach. This lead compound specifically inhibits fusion and spread of live MV and MV glycoprotein-induced membrane fusion. The inhibitor induces negligible cytotoxicity and does not interfere with receptor binding or F protein biosynthesis or transport but prevents F protein-induced lipid mixing. Mutations in the postulated target site alter viral sensitivity to inhibition. In silico docking of the compound in this microdomain suggests a binding model that is experimentally corroborated by a structure-activity analysis of the compound and the inhibition profile of mutated F proteins. A second-generation compound designed on the basis of the interaction model shows a 200-fold increase in antiviral activity, creating the basis for novel MV therapeutics. This template-based design approach for MV may be applicable to other clinically relevant members of the paramyxovirus family.  相似文献   
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Immune check-point inhibitors (ICIs) have changed our view on how to treat cancer. Despite their approval in treatment of many different cancers, efficacy of immune check-point inhibitors (ICI) in neuroendocrine neoplasia is limited and poorly understood. Established treatment options of neuroendocrine tumors (NET) and neuroendocrine carcinomas (NECs) are based on surgery, tumor-targeted medical treatments, Peptide Receptor Radionuclide Therapy (PRRT), and locoregional therapies. However, in many patients these treatments lose efficacy over time, and novel therapies are urgently needed. We report on 8 patients diagnosed with neuroendocrine neoplasms (NEN) that were treated with ICI (pembrolizumab, avelumab, nivolumab plus ipilimumab) as salvage therapy. In this cohort, we observed tumor response with partial remission in 3 patients and stable disease in 1 patient. Four patients showed progressive disease. Of note, responses were observed both in PD-L1 positive and PD-L1 negative patients. Here, we discuss clinical courses of these patients in the context of available literature to highlight limitations and drawbacks currently preventing the use of ICI in routine management of patients with NEN.  相似文献   
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The aim of the study is to review the clinical manifestations and the hematological findings of brucellosis and pancytopenia, with or without hematological malignancies. The records of 202 patients with brucellosis were evaluated retrospectively. Among these cases of brucellosis seen in a 6 year period between April 1999 and June 2005, 30 patients with pancytopenia were identified. The most common manifestation was fever, followed by weight loss, anorexia, malaise, arthralgia, and hepatosplenomegaly. Bone marrow biopsies revealed hypercellularity or normocellularity. The most common findings in the bone marrow evaluation were histiocytic hemophagocytosis and granulomas. Among all cases, we diagnosed 5 hematological malignancies (1 acute myelogenous leukemia, 2 acute lymphoblastic leukemia, and 2 multiple myeloma) concurrently with brucellosis. The clinical symptoms and findings were similar in patients with and without malignancies. In cases with malignancies, the bone marrow biopsy revealed predominant primary disease involvement. Significant increases in ESR and CRP, severe anemia and thrombocytopenia were observed in patients with malignancies. Peripheral blood counts in patients without malignancies returned to normal after antibiotic treatment for brucellosis. However, pancytopenia in two patients with malignancies did not recover because of primary resistant disease. We conclude that while histiocytic hemophagocytosis may be considered as a major cause of pancytopenia, leukemic infiltration can also be an extreme and unusual cause of pancytopenia in patients in whom brucellosis was concurrently diagnosed with hematological malignancies.  相似文献   
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OBJEctive: The oxidant-antioxidant balance plays an important role in the pathogenesis of COPD. The aim of the present study was to evaluate the effects of exercise, as an oxidative stress factor on the oxidant-antioxidant balance and to investigate whether short-term antioxidant treatment affects lipid peroxidation products. METHODOLOGY: Twenty-one stable COPD patients and 10 control subjects were included in the study. Symptom-limited exercise tests were performed by all subjects. Blood was collected before and 1 h after exercise in control subjects and before, 1 and 3 h after exercise in COPD patients, for analysis of malondialdehyde (MDA), reduced glutathione (GSH) and vitamin E (VE) levels. VE and vitamin C treatments were added to the regular bronchodilator therapy in 10 COPD patients for 1 month. After the treatment period, an exercise test was performed and blood was collected again for MDA, GSH and VE levels. RESULTS: Baseline GSH and VE levels were significantly lower in the COPD group when compared with the control subjects. There was no statistically significant difference in MDA levels between the two groups. In the COPD group, MDA levels 3 h after exercise were significantly higher than at baseline. In contrast there were no significant differences in MDA, VE and GSH levels in the control group after exercise. VE and MDA levels increased significantly after exercise in COPD patients but there was no difference in GSH levels. Baseline exercise time was significantly lower in the COPD group than in the controls. In 10 COPD patients who were given antioxidant therapy, their exercise time increased significantly and there was no increase in MDA and VE levels after the repeated exercise test. CONCLUSIONS: Antioxidant levels were significantly lower in COPD patients than in control subjects. In these patients, exercise results in more significant oxidative stress and lipid peroxidation than in control subjects and antioxidant therapy may decrease lipid peroxidation following exercise and improve exercise capacity.  相似文献   
40.
ABILOCO-Kids is a scale that assesses the walking ability of children with Cerebral Palsy (CP) from the viewpoint of parental perception. The aim of this study was to translate the ABILOCO-Kids scale into Turkish and to establish its reliability and validity in children with CP. Turkish children were recruited in this study. ABILOCO-Kids is a scale developed by Caty and et al. This scale assess the walking ability of children with CP focusing on the activity domain of the International Classification of Functioning, Disability and Health (ICF). The ABILOCO-Kids scale was translated from English into Turkish using the forward-backward-forward method. The motor functions of the 63 children participating in the study were evaluated by the Gross Motor Function Classification System (GMFCS) and the Gross Motor Function Measurement-88 (GMFM-88). The ABILOCO-Kids scale was repeated in 30 children after one week to establish test-retest reliability. While internal and external construct validity were investigated using Rasch analysis and Spearman correlation coefficient, respectively; reliability was evaluated in terms of internal consistency by Cronbach’s alpha and Person Separation Index (PSI). All items of the ABILOCO-Kids were found to fit the Rasch Model (chi-square 14.35 (df?=?20), p?=?0.813). The internal construct validity was good, overall mean item fit residual was ?0.109 (SD: 0.719) and mean person fit residual was ?0.215 (SD: 0.817). The reliability was good with Cronbach’s Alpha of 0.98 and PSI of 0.99. When the test-retest was examined via Differential Item Functioning (DIF) by time, none of the items showed DIF. Spearman correlation coefficients of the ABILOCO-Kids scale in relation to the GMFM and GMFCS were r?=?0.824, p?<?0.001; r?=??0.788, p?<?0.001 respectively. The Turkish version of the ABILOCO-Kids scale is a valid, reliable and unidimensional scale for children with CP. This scale will allow the differences in the locomotion of children with CP to be evaluated from the perspective of the family.  相似文献   
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