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The study aimed at determining the effect of melatonin on the activity of protective antioxidative enzymes in the heart and of lipid peroxidation products in the course of intoxication with doxorubicin (DOX). The rats were categorized into four groups, receiving: 0.9% NaCl i.p. (NaCl control); melatonin [20 mg/kg body weight (b.w.)] s.c. (control Mel); DOX (2.5 mg/kg b.w.) i.p.; melatonin plus DOX in doses as above. All the substances were administered once in a week for four consecutive weeks. Homogenates of heart tissue were examined for activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), levels of reduced glutathione (GSH) and of lipid peroxidation indices (MDA + 4-HDA). Administration of melatonin alone did not induce alterations in levels of MDA + 4-HDA, GSH, or in activity of GPx, SOD or CAT, as compared to the group receiving 0.9% NaCl. GSH levels decreased following DOX but remained at normal levels following DOX and melatonin. The level of MDA + 4-HDA increased following DOX, as compared with the control, a change prevented by the combination of DOX + melatonin. Activities of GPx, SOD and CAT were higher in groups receiving DOX and/or DOX plus melatonin than in control groups. Activity of CAT and the level of GSH in the group receiving DOX plus melatonin were significantly higher than in the group intoxicated with DOX alone. The obtained results demonstrate that, when given in parallel with DOX, melatonin protects cardiomyocytes from damaging effects of the cytostatic drug (reflected by the levels of MDA + 4-HDA). The protective effect resulted, in part from the augmented levels of GSH and from stimulation of CAT activity by melatonin in cardiomyocytes subjected to the action of DOX.  相似文献   
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Neoangiogenesis is essential for tumor and metastasis growth, but this complex process does not follow the same activation pathway, at least in tumor cell lines originated from different murine mammary adenocarcinomas. LMM3 cells were the most potent to stimulate new blood vessel formation. This response was significantly reduced by preincubating cells with indomethacin and NS-398, non-selective cyclooxygenase (COX) and COX-2 selective inhibitors, respectively. COX-1 and COX-2 isoenzymes were both highly expressed in LMM3 cells, and we observed that indomethacin was more effective than NS-398 to inhibit prostaglandin E2 (PGE2) synthesis. In addition, nitric oxide synthase (NOS) inhibitors, Nomega monomethyl L-arginine and aminoguanidine, also reduced LMM3-induced angiogenesis and nitric oxide (NO) synthesis as well. NOS2 > NOS3 proteins and arginase II isoform were detected in LMM3 cells by Western blot. The latter enzyme was also involved in the LMM3 neovascular response, since the arginase inhibitor, Nomega hydroxy L-arginine reduced the angiogenic cascade. On the other hand, parental LM3 cells were able to stimulate neovascularization via COX-1 and arginase products since only indomethacin and Nomega hydroxy L-arginine, which diminished PGE2 and urea synthesis, respectively, also reduced angiogenesis. In turn, LM2 cells angiogenic response could be due in fact to PGE2-induced VEGF liberation that stimulated neoangiogenesis at very low levels of NO.  相似文献   
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The vascular adventitia is emerging as an important modulator of vessel remodeling. Adventitial myofibroblasts migrate to the neointima after balloon angioplasty, contributing to restenosis. We postulated that angiotensin II (Ang II) enhances adventitial myofibroblast migration in vitro via reduced nicotinamide-adenine dinucleotide phosphate oxidase-derived H(2)O(2) and that Nox4-based oxidase promotes migration. Ang II increased myofibroblast migration in a concentration-dependent manner, with a peak increase of 1023+/-83%. Rat adventitial myofibroblasts were cotransfected with human Nox4 and human p22-phox plasmids or an empty vector. PCR showed an 8-fold increase in human Nox4 and human p22-phox plasmid expression. Using RT-PCR with primers specifically designed for rat reduced nicotinamide-adenine dinucleotide phosphate oxidases, endogenous Nox levels were determined. Ang II decreased endogenous Nox4 and Nox1 mRNA to 41% and 27% of control, respectively, but had no effect on Nox2. Cotransfection with human Nox4 and human p22-phox plasmids combined with Ang II reduced endogenous Nox4 mRNA levels (37+/-5% of control; P<0.05), whereas it had no significant effect on Nox1 or Nox2. In empty vector-transfected cells, Ang II increased myofibroblast migration by 192+/-32% versus vehicle (P<0.01) while increasing H(2)O(2) (473+/-22% versus control; P<0.001). Cotransfection with human Nox4 and human p22-phox plasmids decreased Ang II-induced migration (46+/-6%; P<0.001) in parallel with attenuation of H(2)O(2) production (23+/-8% versus empty vector; P<0.05). Our data suggest that Nox4 promotes Ang II-induced myofibroblast migration via an H(2)O(2)-dependent pathway. The data also suggest that Nox4 causes feedback inhibition of its own expression in adventitial myofibroblasts.  相似文献   
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Probability of cure in elderly Hodgkin's disease patients   总被引:2,自引:0,他引:2  
BACKGROUND: Elderly Hodgkin's disease patients have a poor prognosis. The question arises whether these patients need aggressive treatment or a palliative strategy. So far, as a consequence of the scarcity of trials designed for them, useful information can be obtained only by retrospective analyses. METHODS: We retrospectively studied clinical data from 567 patients recorded from 1982 to 1989 in the Piemonte Hodgkin's Disease Register (PHDR). The 65 patients over 65 years of age were compared to younger ones. We analyzed the role of disease independently of confounding variables, mainly inadequacy of staging and/or treatment, comorbidity and toxicity. RESULTS: In the elderly comorbidity was as high as 35%. Forty elderly patients (60%) entered a suboptimal plan with a low degree of aggressivity, which was different from the usual PHDR protocol. Elderly patients also had a high proportion of subsequent protocol interruptions (25%). Chemotherapy dose intensity was negatively affected by advanced age (p < 0.01 after both 3 and 6 courses of chemotherapy). Toxic deaths were significantly higher in elderly patients than in younger ones (14% vs 1%; p < 0.05). CR rates, overall survival (OS), disease-specific survival (DSS) and event free survival (EFS) were all significantly influenced by age (p < 0.01). Relapse-free survival (RFS) in patients achieving CR did not differ according to age class (77% vs 60%; p = ns). RFS was better in elderly patients entering the PHDR protocols than in those following an alternative plan (75% vs 54%; p = 0.04); however, elderly patients treated according to PHDR guidelines showed a higher incidence of toxic deaths than those treated less aggressively (23% vs 8%). The two groups had similar EFS (36% vs 24%; p = ns). CONCLUSIONS: Elderly patients who achieve CR can have good RFS and cure is possible, but the toxic cost of conventional strategies is unacceptable and selected strategies still must be found.  相似文献   
90.
A young women affected by Hodgkin's disease developed chronic autoimmune thrombocytopenic purpura. Splenectomy induced normalization of her platelet count, but hemorrhagic symptoms did not disappear. The patient's platelets did not aggregate in response to collagen and ADP and the IgG fraction of the patient's plasma induced the same defect in normal platelets. The women's IgG recognized glycoproteins IIb and IIIa of normal platelet membranes. Prednisone therapy induced the disappearance of bleeding symptoms and the normalization of platelet aggregation.  相似文献   
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