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981.
Kaya Yorganci Ata? Baykal Murat Kologlu Zeynep Sariba? Gülsen Hascelik Iskender Sayek 《Journal of investigative surgery》2004,17(3):119-126
The aim of this study was to investigate the relationship between the obstructive jaundice-induced cellular immune suppression and endotoxin challenge with respect to the levels of tumor necrosis factor (TNF), interleukin-10 (IL-10), and interleukin-2 (IL-2). Rats underwent either bile duct ligation or sham operation. At 21 days, all rats were challenged either with lipopolysaccharide (LPS) or saline. In the sham-operated group LPS injection significantly increased TNF levels at 90 min. The common bile duct ligated group showed a significant increase in TNF levels compared with all other groups, including the sham-operated, LPS-injected group, at 90 min. At 180 min following LPS challenge, TNF levels decreased, and there was no difference between any of the LPS-challenged groups at 180 min and any of the saline groups at either 90 or 180 min. In the sham-operated group, LPS injection significantly increased IL-10 levels at both 90 and 180 min. In the bile duct ligated group, LPS injection significantly increased IL-10 levels compared with saline injection at both 90 and 180 min. On the other hand, bile duct ligated animals had significantly less increase in IL-10 levels following LPS challenge at 90 min but not at 180 min. In common bile duct ligated rats, LPS challenge induced a significantly greater increase in IL-2 levels compared with all other groups. In conclusion, in the presence of obstructive jaundice, endotoxemia primes a more vigorous inflammatory response despite cellular immune depression. 相似文献
982.
Effects of volatile anesthetics on mechanical properties of rat cardiac skinned fibers 总被引:12,自引:0,他引:12
Volatile anesthetics were demonstrated to decrease calcium sensitivity and maximal developed force of detergent-treated rat cardiac skinned fibers. To further investigate the possible mechanisms involved in the decrease of force production, stiffness measurements were performed at defined levels of activation with the use of quick length changes of 0.3 to 4% of initial muscle length in the absence and in the presence of 2 MAC of halothane, enflurane, or isoflurane. The results of various series of experiments suggest that these anesthetics have multiple sites of action on cardiac myofibrillar proteins: 1) they decreased active stiffness indicating a decreased number of attached force-generating cross-bridges; 2) they increased the stiffness/force ratio suggesting that the individual force developed by each cross-bridge was decreased during anesthetic exposure; and 3) they increased the time constant of force recovery, which is consistent with the decreased rate of ATP hydrolysis described by others. These changes in cross-bridges kinetics and efficiency may result from conformational changes in all the protein systems involved in force production, and especially actin-myosin attachment and detachment. However, the changes observed were small despite a relatively high concentration of anesthetics; therefore, they will probably participate only to a moderate extent in the overall negative inotropic effect of these agents. 相似文献
983.
Murat Bozlu Erdal Doruk Erdem Akbay Ercüment Ulusoy Selahíttín Çayan Deníz Acar Emíne Arzu Kanik 《International journal of urology》2002,9(8):417-421
OBJECTIVES: To compare the effectiveness of the International Prostate Symptom Score (IPSS) when administered by the physician to when self-administered by the patient. The effect of the patient's educational level on the IPSS was also evaluated. METHODS: One hundred and seven previously untreated patients with symptomatic benign prostatic hyperplasia (BPH) completed the Turkish version of the International Prostate Symptom Score (Turkish I-PSS) and quality of life (QOL) questionnaires during a single office visit, first on their own and then with an interviewing physician. The patients were categorized into three groups according to their educational levels. Paired t-tests were performed to compare the total IPSS (tIPSS) and QOL results between the two testing modes. IPSS and QOL scores resulting from both modes were compared using a kappa test. Differences between the physician-assisted and self-administered scores among the different educational groups were further compared using a one-way anova test and Post Hoc Multiple Comparisons. To compare the objective effectiveness of tIPSS and QOL between the two testing modes, we selected the positive actual state, which was maximum urine flow (Qmax) of 15 mL/s or less and constructed receiver operating characteristics (ROC) curves for all patients. This estimation was constructed for each educational level. RESULTS: There were no statistical differences in IPSS and QOL values obtained by the patients or physicians (P > 0.05). The ROC areas for tIPSS were 0.94 and 0.93, and the ROC areas for QOL scores were 0.97 and 0.91 for information obtained by physicians and patients, respectively. When IPSS answers and QOL scores were evaluated separately, consistency was found across both modes of administration. However, there were lower levels of consistency in answers to IPSS questions 2, 5 and 6 (P = 0.59;0.42; 0.52, respectively). There was no significant difference among the aforementioned data in the educational groups. CONCLUSION: Although the total IPSS and QOL scores were not affected by the different modes of administration, we recommend that the physicians should evaluate answers to questions 2, 5 and 6 carefully. The present study demonstrates that the educational level did not affect the IPSS and QOL when administered either by the physician or the patient. 相似文献
984.
Fatih S Erol Metin Kaplan Murat Tiftikci Huseyin Yakar Ibrahim Ozercan Necip Ilhan Cahide Topsakal 《Journal of clinical neuroscience》2008,15(7):784-790
In this study, we aimed to investigate the biochemical and histopathological protective effects of octreotide and melatonin in an experimental model of spinal cord injury. Fifty- six male albino Wistar rats were divided into four groups. Rats in the G1 group (n=7; control group) did not undergo any treatment except for anesthesia prior to being killed. Rats in the G2 group (n=7) underwent laminectomy and aneurysmal clip application at the T4-5 level. G3 group rats (n=14) were either treated with a 7.5 mg/kg intraperitoneal dose of melatonin (Sigma, St. Louis, MO, USA) immediately after laminectomy, then the same dose again on the day following injury (G3a), or given three equal doses over 10 days to achieve a total dose of 7.5 mg/kg/day (G3b). G4 group rats (n=14) were either treated with a 30microg/kg intraperitoneal dose of octreotide (Sandostatin; Novartis, Istanbul, Turkey) immediately after laminectomy, then the same dose again on the day following injury (G4a), or given three equal doses over 10 days to achieve a total dose of 30miocrog/kg/day (G4b). Rats in the G3 and G4 groups were sacrificed on days 1 and 10 after spinal cord injury (n=7 at each time point) and spinal cord samples were obtained. Tissue malonyldialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) levels were assayed. G3a, G3b and G4b had significantly lower levels of MDA than G2 (p<0.01). G3b had significantly higher SOD and GSH-Px levels than G2 (p<0.01). Histopathologically, melatonin significantly reduced necrosis and degeneration in both the initial and late stages (p<0.01). Octreotide had significant effects on necrosis and degeneration during the late stages, and on edema and congestion in both the initial and the late stages of injury (p<0.01). Melatonin was found to be superior to octreotide with respect to the prevention of congestion, edema, axonal degeneration and necrosis. 相似文献
985.
986.
Calcium chloride salt is the principle ingredient of many commercially available deicers. Calcium chloride melts snow and ice by its osmotic action. We present a case of skin and soft tissue necrosis associated with the use of a calcium chloride-containing deicer. Although calcium chloride is known to produce soft tissue necrosis if it extravasates during intravenous administration, necrosis and skin sloughing has rarely been described after topical exposure to this salt. Calcium chloride likely produces tissue injury from the heat liberated by mixing calcium chloride with water (exothermic reaction) and from direct calcium deposits in the skin (calcinosis cutis) and soft tissue. 相似文献
987.
Herken H Gurel A Selek S Armutcu F Ozen ME Bulut M Kap O Yumru M Savas HA Akyol O 《Archives of medical research》2007,38(2):247-252
BACKGROUND: There has been much evidence in recent years that free oxygen radicals and nitric oxide (NO) may play an important role in the pathophysiology of neuropsychiatric disorders. In this study, we aimed to investigate whether NO, xanthine oxidase (XO), superoxide dismutase (SOD), and adenosine deaminase (ADA) levels are associated with major depression (MD) and to evaluate the impact of antidepressant treatments on NO, SOD, ADA and XO levels in MD. METHODS: Thirty-six patients who were diagnosed as MD according to DSM-IV criteria and 20 healthy controls were included. The serum levels of NO, XO, SOD, and ADA were measured by spectrophotometric methods both in patients and controls. Patients were treated with antidepressant drugs for 8 weeks. All patients were assessed by Hamilton Depression Rating Scale (HDRS) both before and after antidepressant treatment. RESULTS: ADA and XO levels of the patients were significantly higher than the controls. SOD level of the patients was significantly lower than the controls. Although NO levels of the patients were higher than the controls, the difference was not statistically significant. There was no correlation between HDRS and the parameters studied (SOD, ADA, XO, and NO) of the patients. After 8 weeks of antidepressant treatment, ADA and SOD activities were increased, whereas NO and, XO levels decreased significantly. CONCLUSIONS: ADA, XO, and SOD activity may have a pathophysiological role in MD and may predict prognosis of MD. Activity of these enzymes may be used to monitor effects of the antidepressant treatment. 相似文献
988.
Yaman M Eser O Cosar M Bas O Sahin O Mollaoglu H Fidan H Songur A 《Archives of medical research》2007,38(5):489-494
BACKGROUND: The beneficial effects of avocado/soybean unsaponifiables (ASU) are known as an antiarthritic agent. This experimental study presents the effects of ASU on oxidant/antioxidant systems and the number of apoptotic neurons of hippocampal formation after ischemia and reperfusion. METHODS: Eighteen rats were divided into three equal groups: group I rats were used as controls; group II rats were fed with standard diet and group III rats were fed with standard diet plus ASU pills for 10 days. One day after electrocauterization of bilateral vertebral arteries for groups II and III, bilateral common carotid arteries were occluded for 30 min and then reperfused for 30 min. After these procedures, rats of all groups were sacrificed. The levels of malondialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus. The number of apoptotic neurons was counted by Tunel method in histological samples of right hippocampus. RESULTS: MDA and NO levels increased in group II compared with group I rats (p = 0.002, p = 0.015). In group III, MDA and NO levels decreased as compared to group II (p = 0.041, p = 0.002). SOD and CAT activities increased in group III as compared to group II rats (p = 0.002, p = 0.002). The number of apoptotic neurons was lower in group III as compared to group II rats. CONCLUSIONS: The present findings suggest that ASU could decrease oxidative stress and apoptotic changes in ischemic rat hippocampus. Dietary supplementation of ASU may be beneficial to prevent or ameliorate ischemic cerebral vascular disease. 相似文献
989.
Inanç B Eser Elçin A Koç A Baloş K Parlar A Murat Elçin Y 《Journal of biomedical materials research. Part A》2007,82(4):917-926
Periodontal ligament cells play a crucial role in the regeneration of periodontal tissues and an undifferentiated mesenchymal cell subset is thought to exist within this population. The aim of this study was to assess the osteogenic differentiation potential of human periodontal ligament fibroblasts (hPDLFs) in three dimensional (3D)-osteogenic culture environment following encapsulation in chitosan-hydroxyapatite (C/HA) microspheres with the size range of 350-450 microm. Human PDLF cultures were established and three experimental groups were formed: (i) two-dimensional (2D)-culture as single cell monolayer, (ii) 3D-static culture of C/HA encapsulated hPDLFs, and (iii) 3D-dynamic culture of C/HA encapsulated hPDLFs in a rotating wall vessel bioreactor. The cells were cultured in standard culture medium supplemented with beta-glycerophosphate, dexamethasone, and ascorbic acid. After 21 days, immunohistochemistry was performed using antibodies against osteonectin, osteopontin, bone-sialoprotein, and osteocalcin as osteogenic differentiation markers. Phase-contrast and scanning electron microscopy observations were used for histological and morphological evaluation. The combined effects of osteoinductive medium and HA-containing composite microsphere material on encapsulated hPDLFs resulted in the transformation of a considerable portion of the cells into osteoblastic lineage at the end of the experiments. Results demonstrate the ability of hPDLFs to undergo osteogenic differentiation upon induction in vitro, both under 2D and 3D culture conditions. C/HA microspheres in microgravity bioreactor may serve as a suitable 3D environment to support the osteogenic differentiation of human PDLFs, in vitro. 相似文献
990.
Enoz M Kiyak E Katircioglu S Gulluoglu M 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2007,50(2):157-158
Case report about laryngeal localization of a granular cell tumor in a 38 years old female without recurrence over an observation period of two years. 相似文献