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Introduction

Ozone has been proposed as an antioxidant enzyme activator, immunomodulator and cellular metabolic activator. This study was designed to investigate the efficacy of ozone therapy in the prevention of esophageal damage and stricture formation developed after esophageal caustic injuries in the rat.

Materials and Methods

Forty-five rats were allocated into three groups; sham-operated, un-treatment and treatment groups. Caustic esophageal burn was created by instilling 15% NaOH in the distal esophagus. The rats were left untreated or treated with 1 mg/kg/day ozone intraperitoneally. All rats were sacrificed at 28 days. Efficacy of the treatment was assessed by measuring the stenosis index (SI) and histopathologic damage score, and biochemically by determining tissue hydroxyproline content (HP), superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA) and protein carbonyl content (PCC) in esophageal homogenates.

Results

Whereas seven (47%) rats died in the un-treatment group, all rats in the sham-operated and the treatment group survived during the study. SI, the histopathologic damage score, was significantly lower in the ozone-therapy group than the un-treatment group. HP levels were significantly higher in the un-treatment group than the group treated with ozone. Caustic esophageal burn increased MDA and PCC levels and also decreased SOD and GPx enzyme activities. In contrast, ozone therapy decreased the elevated MDA and PCC levels and also increased the reduced SOD and GPx enzyme activities.

Conclusion

Ozone has a preventive effect in the development of fibrosis by decreasing tissue damage and increasing the antioxidant enzyme activity in an experimental model of corrosive esophageal injury.  相似文献   
84.
Background, Objectives, and METHODS: The number of patients on chronic peritoneal dialysis (CPD) is increasing rapidly on a global scale. We analyzed the International Pediatric Peritoneal Dialysis Network (IPPN) registry, a global database active in 33 countries spanning a wide range in gross national income (GNI), to identify the impact of economic conditions on CPD practices and outcomes in children and adolescents. ? RESULTS: We observed close associations of GNI with the fraction of very young patients on dialysis, the presence and number of comorbidities, the prevalence of patients with unexplained causes of end-stage kidney disease, and the rate of culture-negative peritonitis. The prevalence of automated PD increased with GNI, but was 46% even in the lowest GNI stratum. The GNI stratum also affected the use of biocompatible peritoneal dialysis fluids, enteral tube feeding, calcium-free phosphate binders, active vitamin D analogs, and erythropoiesis-stimulating agents (ESAs). Patient mortality was strongly affected by GNI (hazard ratio per $10 000: 3.3; 95% confidence interval: 2.0 to 5.5) independently of young patient age and the number of comorbidities present. Patients from low-income countries tended to die more often from infections unrelated to CPD (5 of 9 vs 15 of 61, p = 0.1). The GNI was also a strong independent predictor of standardized height (p < 0.0001), adding to the impact of congenital renal disease, anuria, age at PD start, and dialysis vintage. Patients from the lower economic strata (GNI < $18 000) had higher serum parathyroid hormone (PTH) and lower serum calcium, and achieved lower hemoglobin concentrations. No impact of GNI was observed with regard to CPD technique survival or peritonitis incidence. ? CONCLUSIONS: We conclude that CPD is practiced successfully, albeit with major regional variation related to economic differences, in children around the globe. The variations encompass the acceptance of very young patients and those with associated comorbidities to chronic dialysis programs, the use of automated PD and expensive drugs, and the diagnostic management of peritonitis. These variations in practice related to economic difference do not appear to affect PD technique survival; however, economic conditions seem to affect mortality on dialysis and standardized height, a marker of global child morbidity.  相似文献   
85.
The authors report 3 cases of Hodgkin's disease with intracranial involvement. The patients were 4, 12, and 15 years old (male/female = 1/2). Initially, they were treated with ABVD or COPP chemotherapies and low-dose involved field radiotherapy. Intracranial recurrences occurred 27, 40, and 42 months after initial diagnosis, respectively. Two patients experienced convulsions and the other complained of diplopia. The metastatic lesions were located supratentorially with CT or MRI. Despite initial response achieved following systemic chemotherapy and external irradiation to cranial lesions, all patients died with disseminated disease. In patients with intracranial involvement of Hodgkin's disease, prolonged disease-free survival may be achieved by combined modality treatment.  相似文献   
86.

Objective  

To investigate the relationship between human papilloma virus (HPV) infection persistence and serum folate, vitamin B12, homocysteine, neopterin levels in cervical dysplasia.  相似文献   
87.
PURPOSE: To determine the effect of epidural anesthesia (EP) on oxygenation of the chronically ischemic limb in patients undergoing aorto-femoral bypass grafting and to assess whether it produces an alteration of lipid peroxidation and antioxidant status following revascularization. METHODS: In this prospective, randomized, single-blinded study 40 ASA II or III patients undergoing elective aorto-femoral bypass grafting were allocated to receive general anesthesia (group GA, n = 20), or epidural + GA (group EP, n = 20) during surgery. Femoral venous blood-gas status, activities of the protecting antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-px), glutathione reductase (GSH-rd), glutathione (GSH) and thiobarbituric acid-reactive substances (TBARS) as a marker of lipid peroxidation were determined in blood samples taken from the femoral vein at different intervals before and after revascularization. RESULTS: Before the induction of anesthesia in group EP, femoral venous PO(2) [mean (standard deviation), 95% confidence interval] increased after achieving an adequate level of blockade by EP extending to the dermatomal level of T6-8 [29.32 (4.6), 26.34-32.30 to 36.29 (4.6), 33.37-39.22 mmHg, P < 0.05]. Femoral venous PO(2) was similar in both groups thereafter. In the GA group a significant increase in erythrocyte TBARS was observed immediately after restoration of blood flow when compared with baseline values [221.32 (102), 148.35-294-29 to 337.26 (123) 248.99-425.53 nmol*g(-1) hemoglobin, P < 0.01] but not at any other moment. In the EP group TBARS did not increase throughout the study. Within group comparisons revealed no significant differences in GSH, GSH-px, GSH-rd and SOD. CONCLUSION: In patients with atherosclerotic aorto-iliac occlusive disease EP may possibly attenuate lipid peroxidation following revascularization but has no effect on antioxidant enzyme activities.  相似文献   
88.
Early identification of chemotherapy-refractory lymphoma patients provides a basis for alternative treatment strategies. Metabolic imaging with (18)F-FDG PET offers functional tissue characterization that is useful for assessing response to therapy. Our objective was to determine the predictive value of (18)F-FDG PET early during chemotherapy (after 1 cycle) and at the completion of chemotherapy for subsequent progression-free survival (PFS) in patients with aggressive non-Hodgkin's lymphoma (NHL) or Hodgkin's disease (HD). METHODS: (18)F-FDG PET (dual-head coincidence camera with attenuation correction) was performed before and after 1 cycle of chemotherapy on 30 patients (17 NHL, 13 HD; mean age, 52.3 +/- 16.0 y). For 23 of the 30 patients, (18)F-FDG PET data were also obtained after the completion of chemotherapy. The patients had a median follow-up of 19 mo (range, 18-24 mo). Follow-up of PFS was compared between patients with positive and negative (18)F-FDG PET results obtained after the first cycle of chemotherapy and at the completion of chemotherapy. RESULTS: Positive (18)F-FDG PET results obtained both after the first cycle and at the completion of therapy were associated with a shorter PFS (median, 5 and 0 mo, respectively) than were negative (18)F-FDG PET results (PFS medians not reached). A statistically significant difference in PFS between positive and negative (18)F-FDG PET results was obtained both after the first cycle and at the completion of chemotherapy (P < or = 0.001). The PFS and (18)F-FDG PET results obtained after the first cycle correlated better than those obtained after the completion of chemotherapy (r(2) = 0.45 vs. 0.17). (18)F-FDG PET had more false-negative results after the last cycle (6/17 cases, or 35%) than after the first cycle (2/13 cases, or 15%). Thus, (18)F-FDG PET had greater sensitivity and positive predictive values after the first cycle (82% vs. 45.5% and 90% vs. 83%, respectively) than after the last cycle. CONCLUSION: (18)F-FDG PET after 1 cycle of chemotherapy is predictive of 18-mo outcome in patients with aggressive NHL and HD and may earlier identify patients who would benefit from more intensive treatment programs.  相似文献   
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OBJECTIVE: The purpose of this study was to evaluate the long term effect of clopidogrel-based antiplatelet therapy on neointimal formation. METHODS: This study comprised 78 patients with typical stable angina pectoris or documented myocardial ischaemia, and with only one angiographic lesion in one native coronary artery undergoing successful stent implantation without predilatation with C-reactive protein levels < or =5 mg/l at 72 h after the procedure. All patients received dual antiplatelet therapy with 75 mg/day clopidogrel and 300 mg/day aspirin for four weeks. Clopidogrel was switched to isochronous placebo in half of the patients (n=39) at the end of the fourth week. This allocation was maintained for 20 weeks, and at week 24 of the study, coronary angiography and intravascular ultrasound imaging were performed again in all cases in order to evaluate the changes that had occurred in the in-stent neointimal formation; rates of restenosis were also recorded RESULTS: At the end of the follow-up period, angiographic stenosis diameter and restenosis rates were smaller in the clopidogrel group than in the placebo group (23.3% versus 35.6%, p=0.05 and 5.12% versus 10.25%; p=0.03 respectively); the intravascular ultrasonographic neointimal cross sectional area was also smaller in the clopidogrel group (3.6 +/- 2.7 mm(2) versus 5.2 +/- 2.5 mm(2), p=0.03). CONCLUSIONS: Long-term clopidogrel administration significantly reduced neointimal formation at the stent site as well as reducing major clinical events in patients who did not develop high-risk systemic inflammatory response after percutaneous coronary intervention.  相似文献   
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