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91.
Coenzyme Q10 concentrations and antioxidant status in tissues of breast cancer patients 总被引:6,自引:0,他引:6
OBJECTIVES: An increasing amount of experimental and epidemiological evidence implicates the involvement of oxygen derived radicals in the pathogenesis of cancer development. Oxygen derived radicals are able to cause damage to membranes, mitochondria, and macromolecules including proteins, lipids and DNA. Accumulation of DNA damages has been suggested to contribute to carcinogenesis. It would, therefore, be advantageous to pinpoint the effects of oxygen derived radicals in cancer development. DESIGN AND METHODS: In the present study, we investigated the relationship between oxidative stress and breast cancer development in tissue level. Breast cancer is the most common malignant disease in Western women. Twenty-one breast cancer patients, who underwent radical mastectomy and diagnosed with infiltrative ductal carcinoma, were used in the study. We determined coenzyme Q10 (Q) concentrations, antioxidant enzyme activities (mitochondrial and total superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase), and malondialdehyde (MDA) levels in tumor and surrounding tumor-free tissues. RESULTS: Q concentrations in tumor tissues significantly decreased as compared to the surrounding normal tissues (p < 0.001). Higher MDA levels were observed in tumor tissues than noncancerous tissues (p < 0.001). The activities of MnSOD, total SOD, GSH-Px and catalase in tumor tissues significantly increased (p < 0.001) compared to the controls. CONCLUSIONS: These findings may support that reactive oxygen species increased in malignant cells, and may cause overexpression of antioxidant enzymes and the consumption of coenzyme Q10. Increased antioxidant enzyme activities may be related with the susceptibility of cells to carcinogenic agents and the response of tumor cells to the chemotherapeutic agents. Administration of coenzyme Q10 by nutrition may induce the protective effect of coenzyme Q10 on breast tissue. 相似文献
92.
Baris Kuskonmaz Songul Yalcin Ozlem Kucukbayrak Nevin Cetin Mulla Cetin Ilhan Tezcan Duygu Uckan 《Pediatric transplantation》2008,12(1):47-51
Abstract: HSCT associated morbidity and mortality is usually attributed to high-dose chemotherapy/radiotherapy regimens used for conditioning. Glutamine (Gln), a conditionally essential amino acid during severe catabolic states, has been shown to have favorable effects in patients with malignancies and in those undergoing HSCT. However, controversy exists regarding its routine use. Studies in children investigating gln supplementation are very limited. In the present study, including 21 gln-supplemented and 20 control pediatric patients, gln supplementation was shown to reduce the duration of fever and decrease the incidence of SOS during the HSCT course. In addition, a decrease in drug-related toxicity and a trend toward reduced incidence of severe mucositis were observed. 相似文献
93.
The selectivity and specificity of berberine (CAS 2086-83-1) for alpha-adrenoceptor subtypes have been studied. alpha 1-Adrenoceptors were investigated in rat and rabbit aorta and alpha 2-adrenoceptors in guinea-pig ileum preparations. Subtype selectivity was then assessed by calculating the selectivity ratios from Ke (equilibrium constant) values. Berberine was found to be more potent for the postsynaptic alpha 1-adrenoceptors than presynaptic alpha 2-adrenoceptors. The selectivity ratios were 1.9 and 3.1 for rabbit and rat aorta, respectively. In the rabbit aorta, responses to norepinephrine and phenylephrine were both inhibited by berberine with lower affinity than that in the rat aorta. The pA2 values for berberine obtained from the norepinephrine and phenylephrine experiments were also found significantly different in rat aorta. However, similar pA2 values were found in rabbit aorta for those agonists. 相似文献
94.
Paydas S Soydas B Paydas S Balal M Erdogan S Tuncer I 《The Mount Sinai journal of medicine, New York》2005,72(4):279-281
The coexistence of lung cancer and glomerular lesion is not commonly reported. Malignancy-related glomerulopathy is commonly membranous glomerulonephritis. Other glomerulopathies are seldom reported. We report two cases presenting with non-small-cell lung cancer, acute renal failure and nephrotic syndrome secondary to membranoproliferative glomerulonephritis and amyloidosis. 相似文献
95.
Paksoy M Karabiçak I Ayan F Aydoğan F 《The Mount Sinai journal of medicine, New York》2005,72(6):405-408
We report a case of a premenopausal woman with severe constipation causing intermittent obstruction. Colonoscopy revealed a tight rectal stricture; however, mucosal biopsies were normal. Exploratory surgery revealed an intense fibrotic reaction involving the rectum and uterus, necessitating a simultaneous low anterior resection and hysterectomy. Pathology established a diagnosis of endometriosis. Preoperative diagnosis of rectal endometriosis can be difficult to establish. Endometrial deposits do not invade the mucosa; therefore, colonoscopy with biopsies are frequently non-diagnostic. Surgery may be the only definitive way to obtain a certain diagnosis. In cases involving rectal strictures of unknown etiology in premenopausal women, rectal endometriosis must be included in the differential diagnosis. 相似文献
96.
Tasatargil A Ogutman C Golbasi I Karasu E Dalaklioglu S 《Journal of cardiovascular pharmacology》2005,45(6):550-554
The aim of this study was to investigate whether the low-molecular-weight heparins (LMWHs) (eg, nadroparin, enoxaparin, and dalteparin) cause a vasodilatory effect in human internal mammary artery (IMA) and to further compare its effect with unfractioned heparin (UFH). Samples of redundant IMA obtained from 20 patients undergoing a coronary artery bypass graft surgery were cut into 3-mm-wide rings and suspended in 20-mL organ baths. Isometric tension was continuously measured with an isometric force transducer connected to a computer-based data acquisition system. LMWHs (0.5-6 U/mL) caused a concentration-dependent relaxation in the endothelium-intact human IMA rings, which were precontracted with Phe (10(-6) M) (P < 0.05). The vasodilator potency of LMWHs seems to be nearly similar while the maximal effect produced by LMWHs was less pronounced compared with that produced by UFH. Removal of endothelium totally abolished the responses of human IMA to LMWHs as well as UFH (P < 0.05). LMWHs-induced vasodilator effect was significantly attenuated by Nomega-nitro-L-arginine methyl ester (L-NAME, 10(-4) M) but not indomethacin (10(-5) M). Our results have shown that LMWHs cause a dose-dependent relaxation in human IMA but are less effective than that produced by UFH. The vasorelaxant effects induced by each of LMWH are nearly similar and seem to be via endothelium-dependent mechanisms, including generation of nitric oxide. 相似文献
97.
Conservative treatment of scapular neck fracture: the effect of stability and glenopolar angle on clinical outcome 总被引:3,自引:0,他引:3
The aim of this study was to determine the effect of stability and glenopolar angle on the clinical outcome of conservatively treated scapular neck fractures. Eighteen patients with scapular neck fractures were treated with conservative treatment. Twelve of the 18 patients had surgical neck fractures, whilst six of them had anatomical neck fractures. Anteroposterior radiographs and computerised tomography were performed for each patient. Glenopolar angle was measured through anteroposterior radiographs in the scapular plane. After 3-5 weeks of immobilisation, a rehabilitation programme was started, throughout which all the patients were treated in a 3-phase rehabilitation programme. The mean follow-up was 25 months, and the Constant score was 78.83+/-8.12 point (range: 68-94 points). Patient gender and the type of scapular neck fractures had no effect on functionality or clinical outcome (p>0.05), whilst associated injuries significantly affected the clinical outcome (p<0.05). There was a positive correlation between the Constant score and glenopolar angle (r=0.891, p<0.05) and between the age and glenopolar angle (r=0.472, p<0.05). 相似文献
98.
Bulbuller N Ilhan YS Kirkil C Cetiner M Gogebakan O Ilhan N 《The Journal of surgical research》2005,125(1):94-97
BACKGROUND: Peritoneal adhesions are pathological fibrotic bands developing after mesothelial damage. Transforming growth factor beta-1 (TGF-beta1) has mitogenic activities for macrophages and fibroblasts. Over-expression of TGF-beta1 has been implicated in the pathogenesis of several fibrotic disorders. Angiotensin II increases the expression of the TGF-beta1 in fibroblasts. The aim of the study was to investigate the effect of angiotensin converting enzyme inhibitor (ACE) on intraperitoneal adhesions. MATERIALS AND METHODS: Thirty male Wistar albino rats were divided into two groups. In the first procedure, laparotomy was performed through a 3-cm midline incision. Ileum was divided above 10 cm from ileocecal valve and a single-layer ileoileal anastomosis was performed. Although no treatment was given to rats in group 1, lisinopril (an ACE inhibitor) was given to rats in group 2 for postoperative 7 days in drinking water. Estimated amount of supplied lisinopril was 6.5 mg/kg/day. On postoperative 8th day, relaparotomy was performed and adhesions were evaluated. At the same time, blood samples were taken for TGF-beta1 measurements. RESULTS: Adhesion severity was significantly less in the ACE inhibitor group (P < 0.001). While mean TGF-beta1 level was 860.3 +/- 108.1 pg/dl (mean +/- SD) in control group, it was 335.8 +/- 52.4 pg/dl in ACE inhibitor group (P < 0.001). There was a significant correlation between serum TGF-beta1 levels and grade of adhesions (r = 0.948). CONCLUSION: It was concluded that ACE inhibitors might be useful for preventing peritoneal adhesions. 相似文献
99.
Trefoil factor expression in biliary epithelium of graft-versus-host disease of the liver after allogeneic hematopoietic cell transplantation 总被引:1,自引:0,他引:1
Idilman R Erden E Arat M Soydan E Erkan O Kuzu I Sahin Y Coban S Bozdayi M Giraud A Akan H Karayalcin S Ozden A 《Transplantation》2005,80(8):1099-1104
BACKGROUND: The aims of this study were to determine the presence of trefoil factor family-3 (TFF3) expression in biliary epithelial cells (BECs) of chronic graft-versus-host disease (cGVHD) of the liver after allogeneic hematopoietic cell transplantation, to compare such expression in chronic liver diseases (CLD) with/without predominantly biliary disease, and to assess the effect of bile duct injury on the degree of TFF3 expression in BECs of cGVHD. METHODS: A total of 82 paraffin-embedded liver biopsy samples were reviewed. These samples were basically divided into two distinct groups according to the presence of ductal injury: group 1 with CLD and predominantly biliary disease (n=26: 17 cGVHD and 9 primary biliary cirrhosis [PBC]) and group 2 with CLD and predominantly parenchymal liver disease (n=56: 20 steatohepatitis and 36 chronic viral hepatitis). Group 2 was used as the controls. Immunohistochemistry was performed using a polyclonal anti-TFF3 antibody. Real-time quantitative PCR was used for the detection of TFF3 mRNA expression. RESULTS: Positive TFF3 immunohistochemical staining and the presence of TFF3 messenger RNA gene expression was demonstrably higher in group 1 than that in group 2 (P<0.0001 and P<0.05, respectively). No significant difference in terms of positive TFF3 stained BECs between GVHD and PBC samples was observed (P>0.05). The extent of TFF3 expression in GVHD samples with severe ductal injury were significantly more common than that of GVHD samples with mild/moderate ductal injury (P<0.0001). CONCLUSIONS: The expression of TFF3 in cGVHD of the liver is increased in response to bile duct damage and repair. Such expression seems to be related the severity of ductal injury. 相似文献
100.