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81.
Glutathione-S-transferase (GST) genes encode a family of detoxification enzymes that offer protection against endogenous and exogenous sources of reactive oxygen species (ROS). Germline variations in GST genes may alter the catalytic efficiency of GST isoenzymes leading to a potential increase in susceptibility to the genotoxic effects of ROS and electrophilic substances. A nested case-control study design was used to examine the association between the polymorphic GST genes and prostate cancer risk among Finnish male smokers of the ATBC Cancer Prevention Study. A case-case analysis was used to determine the association between these genetic polymorphisms and prostate cancer progression. Germline DNA was obtained from 206 prostate cancer cases and 194 controls frequency matched on age, intervention group and study clinic. Cases and controls were genotyped for three GST genes using MALDI-TOF mass spectrometry or multiplex polymerase chain reaction (PCR). Relative to the wild-type genotype, we observed a 36% reduction in prostate cancer risk associated with the GST-M1-null genotype (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.43, 0.95). Unlike GST-M1, GST-T1-null (OR 0.74, 95% CI 0.42, 1.33) and GST-P1*B (OR 1.10, 95% CI 0.72, 1.69) were not strongly associated with prostate cancer risk. We did not observe any significant associations between the selected polymorphic GST genes and tumour grade or stage. In conclusion, we did not observe a direct association between polymorphic GST-T1 or GST-P1 and prostate cancer risk. Our observation of a relatively strong inverse association between the GST-M1-null genotype and prostate cancer risk needs to be confirmed in larger association studies.  相似文献   
82.
Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor.  相似文献   
83.
Medullary thyroid carcinoma (MTC) is a rare form of thyroid cancer representing about 10% of all thyroid malignancies. It occurs mostly as a sporadic tumor or in association with autosomal dominant inherited cancer syndromes--multiple endocrine neoplasia (MEN) types 2A and 2B and familial MTC. Germline mutations in exons 8, 10, 11, 13, 14, 15 and 16 of the RET proto-oncogene are found in most of the familial cases. There are only a few published data reporting multiple germline mutations in the RET proto-oncogene. We have detected double germline mutations in 2 different exons on the same RET allele in two MEN 2 families. In the MEN 2A family, double germline mutation in exons 10 (Cys620Phe) and 13 (Tyr791Phe) was detected. In the MEN 2B family, beside the classical germline mutation in exon 16 (Met918Thr) a second germline mutation in exon 13 (Tyr791Phe) was found. This study revealed that MEN 2 syndromes can also be caused by double germline mutations in the RET proto-oncogene and these families can be added to small worldwide cohort of families with multiple germline mutations.  相似文献   
84.
Sniff nasal inspiratory pressure (SNIP) measurement is a volitional noninvasive assessment of inspiratory muscle strength. A maximum of 10 sniffs is generally used. The purpose of the present study was to investigate whether the maximum SNIP improved after the tenth sniff. In total, 20 healthy volunteers and 305 patients with various neuromuscular and lung diseases were encouraged to perform 40 and 20 sniffs, respectively. The best SNIP among the first 10 sniffs was lower than the best SNIP among the next 10 sniffs in the healthy volunteers and patients. The SNIP improvement after the twentieth sniff was marginal. In conclusion, a learning effect persists after the tenth sniff. The current authors suggest using 10 additional sniffs when the best result of the first 10 sniffs is slightly below normal, or when sniff nasal inspiratory pressure is used to monitor a progressive decline in inspiratory muscle strength.  相似文献   
85.
This study compared key psychometric properties of the Motivation Assessment Scale (MAS) and the Questions About Behavioral Function (QABF) and explored their convergent validity. Twenty adults with mental retardation and problem behaviors (aggression, self-injury, or property destruction) and 31 respondents participated. Test–retest reliability of the subscales in both scales was good to excellent (Cicchetti, D. V., 1994, Psychol. Assess. 6: 284–290), and—except for 1 QABF subscale—internal consistency was good considering the small number of items and the purpose of the scale. Consistent with some earlier studies, interrater reliability was less satisfactory with both scales falling only into the fair to good range.Correlations between functionally equivalent subscales were statistically significant and were generally higher than correlations between nonequivalent subscales. The QABF and the MAS were found to be comparable in terms of the assessed reliabilities, and both instruments appear to be measuring very similar constructs.  相似文献   
86.
BACKGROUND: Many mild-to-moderately obese individuals (body mass index [BMI] 30-35 kg/m(2)) have serious diseases related to their obesity. Nonoperative therapy is ineffective in the long term, yet surgery has never been made widely available to this population. METHODS: Between 1996 and 2004, 93 patients with a BMI of 30-35 kg/m(2) underwent laparoscopic adjustable gastric banding with the LAP-BAND. All patients were referred by their primary physician, entered into a comprehensive bariatric surgery program at one Australian center, and operated on by one surgeon. Data on all patients were collected prospectively and entered into an electronic registry. The study parameters included preoperative age, gender, BMI, presence of co-morbidities, percentage of excess weight loss, and resolution of co-morbidities. RESULTS: The mean age was 44.6 years (range 16-76), mean weight was 98 kg, and the mean BMI was 32.7 kg/m(2) (range 30-34). Of the 93 patients, 42 (45%) had co-morbidities, including asthma, diabetes, hypertension, and sleep apnea. The proportion of patients in follow-up was 79%, 85%, and 89% at 1, 2, and 3 years, respectively. The mean weight was reduced to 71 kg at 1 year, 72 kg at 2 years, and 72 kg at 3 years. The mean BMI was reduced to 27.2 +/- 2.2, 27.3 +/- 3.1, and 27.6 +/- 3.7 kg/m(2), respectively, and the mean percentage of excess weight loss was 57.9% +/- 24.5%, 57.6 +/- 29.3%, and 53.8% +/- 32.8% at 1, 2, and 3 years, respectively. At 3 years, the BMI was 18-24 kg/m(2) in 34%, 25-29 kg/m(2) in 51%, and 30-35 kg/m(2) in 10%. At 3 years, the percentage of excess weight loss was <25% in 10%, 25-50% in 24%, 50-75% in 51%, and >75% in 10%. The co-morbidities improved or completely resolved in most patients. No mortality occurred. CONCLUSION: We are very encouraged by this series of low BMI patients treated with the LAP-BAND. Their weight loss has been good, the complications have been minimal, and the co-morbidities have partially or wholly resolved. With additional study, it is reasonable to expect the weight guidelines for bariatric surgery to be altered to include patients with a BMI of 30-35 kg/m(2).  相似文献   
87.
The precise molecular cause of insulin resistance has not yet been elucidated. Resistance to the normal action of insulin contributes to the pathogenesis of a number of common human disorders, including type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes mellitus, hypertension, and the Metabolic Syndrome X, thus constituting a major public health problem. A disease program aimed at combating this disorder should focus on the identification of targets for therapeutic intervention which may overcome insulin resistance and hence the associated metabolic consequences characteristic of the Metabolic Syndrome. Although the primary defect in the pathogenesis of type 2 diabetes is unknown, genetic and environmental factors are likely to contribute to the manifestation of this progressive metabolic disorder, which is usually not clinically apparent until mid-life. Defects at the level of glucose uptake/phosphorylation characterize insulin resistance in skeletal muscle of type 2 diabetic patients. Identification of putative components of the insulin receptor-signaling pathway may offer insights into mechanisms involved in insulin resistance. Enhanced flux of free fatty acids due to impaired lipid metabolism may contribute to impaired insulin secretion and peripheral insulin resistance. Genes regulating lipolysis are prime candidates for susceptibility towards the metabolic syndrome. Here we describe pathways constituting complex interactions that control glucose homeostasis. We will be considering (1) regulation of glucose uptake by the insulin receptor signaling pathway, and (2) control of adipogenesis and insulin sensitivity by the sterol response element binding protein (SREBP) pathway.  相似文献   
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90.
BACKGROUND: Psychotic symptoms in Alzheimer disease (AD+P) identify a heritable phenotype associated with more rapid cognitive decline. The authors have proposed that AD+P is itself a composite of a misidentification and a paranoid subtype with increased cognitive impairment restricted to the misidentification type. Most prior studies of the clinical correlates of AD+P have been limited, however, by the inclusion of prevalent cases. METHODS: Subjects with possible or probable AD or mild cognitive impairment (MCI) without psychosis at study entry were assessed at the time of initial presentation and then annually. Psychotic symptoms were assessed using the CERAD Behavioral Rating Scale. Survival analyses used Cox proportional hazard models with time-dependent covariates to examine the predictors of psychosis onset. RESULTS: A total of 288 subjects completed at least one follow-up examination. Mean duration of follow-up was 22.1 months. The incidence of psychosis was 0.19 per person-year. Cognitive impairment was associated with onset of psychosis, largely as a result of its association with onset of the misidentification, but not the paranoid, subtype. Including psychotropic medication use in the model revealed an association of antidepressant use with the onset of psychosis. This latter association appeared to arise from an underlying association between depression and the risk of psychosis onset rather than from antidepressant treatment. CONCLUSION: These findings are consistent with the hypothesis that the misidentification and the paranoid subtypes each define a more biologically homogeneous group than AD+P as a whole. Further exploration of the relationship between depressive symptoms and psychosis in patients with AD is warranted.  相似文献   
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