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OBJECTIVES: To investigate the association between oxidative stress and certain trace elements in the blood of breast cancer patients. DESIGN AND METHODS: Malondialdehyde (MDA) was measured in serum of patients with breast cancer (n = 35) and controls (n = 35) by high performance liquid chromatography. Trace elements were determined by atomic absorption spectrophotometry. RESULTS: In the present study, significantly increased lipid peroxidation, measured as MDA, was demonstrated in the serum of breast cancer patients (p < 0.01). The concentrations of zinc and iron remained unaltered. However, the mean serum copper level in patients with breast cancer was significantly higher than the control group (p < 0.01). In addition, the mean serum selenium level in patients with stage III was significantly lower than the control group (p < 0.05). Moreover, a positive correlation was also observed between copper and MDA levels in the patient group but not in the control group. CONCLUSION: In the present study, the presence of an association between oxidative stress and trace elements was observed in patients with breast cancer. We suggest that increased oxidative stress in patients with breast cancer may result from changes in the levels of certain trace elements.  相似文献   
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Molecular therapy studies to date have examined only a limited number of corrective parameters. To assess more global impacts on cellular gene expression for two major molecular therapeutic approaches, we compared gene versus protein delivery in the human genetic disease junctional epidermolysis bullosa (JEB). Both gene and protein replacement of the laminin 5 beta3 (beta3) adhesion molecule restored normal growth and adhesion to poorly viable JEB cells. Gene expression profiling was then performed using cDNA microarrays. The expression of more genes was normalized after beta3 gene transfer than after protein transfer. As anticipated for beta3 delivery, many of the genes whose expression was restored to the normal range were those encoding adhesion molecules and hemidesmosome components. Although gene transfer normalized the expression of a higher percentage of genes than did protein transfer, neither approach fully normalized expression of all genes examined. In addition, both approaches disrupted the expression of some genes, but protein transfer altered expression of a larger proportion of the genes studied. Our findings suggest that therapeutic gene and protein delivery may exert different effects on gene expression and thus may have implications for the development and analysis of molecular therapies for the treatment of genetic disorders.  相似文献   
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Recent reports suggest that methadone may prolong the QTc interval and cause torsades de pointes. This study was conducted to evaluate the prevalence of QTc prolongation during oral methadone therapy and identify factors associated with prolongation. Patients receiving oral methadone as treatment for chronic pain or addiction were eligible for the study. One hundred four patients who were receiving > or = 20 mg methadone per day for > or = 2 weeks underwent electrocardiograms to measure QTc interval duration. Sixty-three (61%) patients were male and 63 (61%) were receiving methadone maintenance for opioid addiction. The mean (+/- SD) age was 45.3 +/- 9.4 years. The median (range) methadone dose was 110 mg/day (20-1200 mg/day); median (range) number of months on methadone was 12.5 months (1-444 months). The median (range) QTc interval was 428 msec (396-494 msec). Thirty-three percent had QTc prolongation (males 40%, females 20%; P=0.03). No patient had a QTc longer than 500 msec. Significant dose response was observed in males on methadone <12 months (rho=0.60, P=0.02). Our study suggests that methadone may prolong the QTc interval in specific subpopulations but poses little risk of serious prolongation.  相似文献   
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Purpose:

The purpose of this study is to identify the possible factors for preserving the eyes after late or suboptimally treated endogenous endophthalmitis secondary to Klebsiella pneumoniae (KP) liver abscess.

Methods:

A retrospective chart review was conducted for patients admitted with KP liver abscess from January 1991 to June 2012.

Results:

Six hundred and ninety-three patients with KP liver abscess were recorded, in which endophthalmitis was identified in 53 cases (65 eyes, 8.29%). Diabetes was significantly associated with the development of endophthalmitis (p = 0.014). Eleven eyes received their last ocular treatment ≥10 days and final vision ≥ counting fingers, and were defined as benign type KP endophthalmitis. The absence of diabetes was the only consistent candidate factor for benign type KP endophthalmitis.

Conclusion:

A lack of ongoing diabetes is an important factor in preserving eyes with late or suboptimally treated endogenous endophthalmitis second to KP liver abscess.  相似文献   
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