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31.
BACKGROUND: Systematic analysis of the influence of diet on the initiation and progression of prostate cancer is often difficult in human populations, for which dietary variables overlap a diversity of genetic backgrounds and social behaviors. Animal models that emulate human prostate cancer allow experimental analysis of the mechanisms of action of nutritional agents that show anti-prostate cancer activity. METHODS: We have used an orthotopic implant model to characterize the in vivo response of androgen-sensitive LNCaP prostate tumors to three well-characterized soy dietary supplements: isoflavone depleted soy protein, soy phytochemical concentrate (SPC), and genistin. RESULTS: In male SCID mice orthotopically implanted with the androgen-sensitive human prostate cell line LNCaP, dietary supplements of soy protein, genistin, and SPC reduced primary tumor weight by 42% (P = 0.07), 57% (P < 0.05) and 70% (P < 0.005), respectively. All three soy supplements significantly increased tumor apoptosis and decrease microvessel density, with no significant change in tumor proliferation. Each supplement produced a distinct serum androgen response, with genistin producing the greatest decrease in total serum testosterone and dihydrotestosterone (DHT) (P < 0.05) and the greatest increase in testosterone to DHT ratio (P < 0.05) and soy protein the greatest decrease in bioactive androgen (P < 0.05). Only SPC significantly inhibited metastases to lymph nodes and lungs, and only SPC produced a significant increase in tumor p53 expression. CONCLUSION: Taken together, these data suggest that the anti-prostate cancer activity of dietary soy protein, soy phytochemicals, and genistin use different molecular pathways. In addition, we have demonstrated that this animal model can be used in the design of dietary strategies for prostate cancer prevention and therapy.  相似文献   
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A nitroreductase enzyme has been isolated from Escherichia coli B. This enzyme is an FMN-containing flavoprotein with a molecular mass of 24 kDa and requires either NADH or NADPH as a cofactor. Partial protein sequence analysis showed extensive homology with the "classical nitroreductase" of Salmonella typhimurium and a nitroreductase induced in Enterobacter cloacae. In common with the Salmonella enzyme, the E. coli B enzyme is capable of reducing nitrofurazone. The E. coli nitroreductase is also capable of reducing the anti-tumour agent CB1954 [5-(aziridin-1-yl)-2,4-dinitrobenzamide], a property shared with the mammalian enzyme DT diaphorase [NAD(P)H dehydrogenase (quinone)] as isolated from Walker cells. The reduction of CB1954 by the E. coli enzyme results in the generation of cytotoxic species. Both enzymes also share the properties of being able to reduce quinones and are both inhibited by dicoumarol. The nitroreductase is a more active enzyme against CB1954 (kcat = 360 min-1) than Walker DT diaphorase (kcat = 4 min-1) and also has a lower Km for NADH (6 vs 75 microM).  相似文献   
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Differences between painless and painful constipation among community women   总被引:1,自引:0,他引:1  
BACKGROUND: In the Rome II criteria, patients with both constipation and abdominal pain (AP) (i.e., "painful constipation" (PC)), who do not satisfy criteria for irritable bowel syndrome (IBS) are included in the same functional constipation (FC) category as patients with constipation without AP (i.e., "painless constipation" (PLC)). What differences, if any, exist between FC without (i.e., PLC) and with AP (i.e., PC) are unclear. METHODS: To compare clinical features among PLC, PC, constipation-predominant IBS (C-IBS), and non-C-IBS, a validated questionnaire was mailed (with telephone follow-up of nonresponders) to an age-stratified random sample of 5,200 adult women in Olmsted County, Minnesota. RESULTS: Altogether, 2,800 women (53%) responded. The age-adjusted prevalence of PLC (7.1 per 100; 95% confidence interval (95% CI), 6.2-8.0) was higher compared to PC (0.9 per 100; 95% CI, 0.6-1.2). Compared to PLC, patients with PC reported worse general health (i.e., excellent or very good = 37.5% vs 51.2%), more somatic symptoms (mean score = 1.3 vs 0.9), and urinary urgency (% often = 58% vs 32%), and had a higher prevalence of hysterectomy. Bowel symptoms significantly impacted > or =1 domain of quality of life (QOL) in 18% of PC versus 9% of PLC. In a logistic discriminant model, age, general health, impact of bowel symptoms on QOL, somatic symptoms, and urinary urgency independently discriminated between bowel subtypes. CONCLUSIONS: Patients with PC more closely resemble those with C-IBS than PLC. Consideration should be given to separating PC from PLC in the Rome criteria and in therapeutic trials.  相似文献   
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Without strict glycemic control, diabetic pregnancies are frequently complicated by spontaneous abortion, stillbirth, or congenital malformation. Retrospective studies have been largely reassuring that pregnancy does not accelerate morbid outcomes in women with diabetic vascular disease. Improved outcomes of highrisk pregnancy in women with pregestational, type 1, or type 2 diabetes mellitus remain challenging, depending on a comprehensive and multidisciplinary team approach and extensive preconception counseling.  相似文献   
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This study aimed to identify coping patterns used by schizophrenia inpatients in comparison with those used by healthy individuals, and to explore their association with selected clinical and psychosocial variables. The Coping Inventory for Stressful Situations (CISS) was used to assess coping strategies among 237 inpatients who met DSM-IV criteria for schizophrenia and 175 healthy individuals. Severity of psychopathology and distress, insight into illness, feelings of self-efficacy and self-esteem (self-construct variables), social support, and quality of life were also examined. Factor analysis, analysis of covariance and correlations were used to examine the relationships between the parameters of interest. Using dimensional measures, we found that emotion-oriented coping style and emotional distress were significantly higher in the schizophrenia group, whereas the task-oriented coping style, self-efficacy, perceived social support and satisfaction with quality of life were lower compared with controls. When eight CISS coping patterns were defined, the results revealed that patients used emotion coping patterns 5.5 times more frequently, and task and task-avoidance coping patterns significantly less often than healthy subjects. Coping patterns have different associations with current levels of dysphoric mood and emotional distress, self-construct variables, and satisfaction with quality of life. Thus, the identified coping patterns may be an additional useful presentation of the diversity of coping strategies used by schizophrenia patients. Coping patterns may be considered an important source of knowledge for patients who struggle with the illness and for mental health professionals who work with schizophrenia patients.  相似文献   
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This study examined the language development of 55 preschool-age children adopted from China who had resided in their permanent homes for approximately 2 years or longer. Slightly over 5% of the children scored below average on 2 or more measures from a battery of standardized speech-language tests normed on monolingual English speakers. However, the vast majority scored within or well above the average range on 2 or more measures. Contrary to other reports on the language development of internationally adopted children, the results suggest that "second first language" acquisition proceeds rapidly in the majority of preschool-age children adopted as infants and toddlers. For the children in the sample who scored below average, results indicated that they were among the children who had been exposed to English for the least amount of time. The results of this study demonstrate both the robustness of the language system in the majority of adopted children from China as well as slower growth in a small subset of lower performers in the 1st years after adoption.  相似文献   
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Simulations play an increasingly important role in the evaluation of osteoporosis interventions. Existing evaluations have been based on reduced-form cohort simulations that do not reflect the complexity and heterogeneity of osteoporosis and its outcomes. Such simplified models offer parsimony and ease of use, but they also are limited in their ability to explain and extrapolate outcomes in a way that is most useful for both clinical and health policy decision makers. Alternatively, evaluations could be based on structural microsimulations, which explicitly model the underlying biology of osteoporosis at the individual level. The structural approach presents technical challenges, including the need to obtain more-detailed data and the requirement that underlying biological models be validated. However, evaluations based on structural microsimulation may ultimately provide substantially more useful information, resulting in improved decision making.  相似文献   
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