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81.
Polymorphisms in genes encoding polycyclic aromatic hydrocarbon (PAH) metabolizing enzymes may alter metabolism of these carcinogens and contribute to inter-individual difference in urine concentrations. We investigated the influence of genetic polymorphism on PAH metabolism in urine from 199 healthy subjects from Southern Brazil. We measured urine 1-hydroxypyrene glucuronide (1-OHPG) concentrations using immunoaffinity chromatography and synchronous fluorescence spectroscopy and genotyped subjects using standard methods. Genetic variants in CYP1B1 (rs1056827, rs1800440, rs10012) were strongly associated with urine 1-OHPG with P-values < 0.010. Variants in aryl hydrocarbon receptor (Ahr) (rs4986826), CYP1A1 (rs1799814) and CYP1A2 (rs2069514) were also, although less strongly, associated with changes in urine 1-OHPG concentrations. These variants had P-values of 0.074, 0.040 and 0.025, respectively. The median urine 1-OHPG concentrations (pmol/ml) in the homozygous wild-type and homozygous variants for CYP1B1 (rs10012) and the Ahr, CYP1A1 and CYP1A2 variants listed above were 2.16 and 0.10, 2.16 and 0.41, 2.03 and 0.46, 2.19 and 2.79, respectively. We found no effect of deletions in GST M1 or GST T1, or different alleles of UGT1A1*28. Adjusting for age, sex, place of residence, tobacco smoke exposure, maté drinking, cacha?a and barbeque preparation had only a minor impact on the associations. A model containing just exposure variables had an r2 of 0.21; a model with single genotypes for Ahr, CYP1A1, CYP1A2 and CYP1B1 had an r2 of 0.10; and a model combining both exposure and genotype information had a total r2 of 0.33. Our results suggest that CYP1B1 genotypes are strongly associated with urine 1-OHPG concentrations in this population.  相似文献   
82.
Measuring the results of rehabilitation interventions presents a number of issues regarding content and method, two of which have been selected for discussion in view of the findings of current research--the significance of patient orientation and the relation to the International Classification of Functioning, Disability and Health, ICF. Compilation of patients' treatment goals, expectations and preferences, patient participation in the development of assessment instruments, compilation of patients' evaluations of treatment results and consideration of the subjectivity of the physician as well as interaction between patient and physician were discussed with respect to involving patients in measuring results. The ICF is a terminology system presenting a uniform international classification for describing health conditions that could assume the function of a common language for the members of various occupations involved in medical rehabilitation. Orienting the measurement of results to the ICF is an obvious next step. This can promote patient orientation, as the categories used by the ICF--in particular for the domains of activities and participation--are formulated in terms relevant to daily routine and are thus pertinent to the patients' lifestyle. The consequences resulting from this overview concern future research needs on the one hand, and on the other hand tips for carrying out a patient-oriented, ICF-based measurement of results. The need for research becomes especially clear regarding the measurement of results based on patient preferences, the determination of the participation relevance perceived by the patient as a criterion for "patient significance" (analogous to "clinical significance"), the integration and weighting of patient and physician assessments of success, the consideration of physicians' subjective concepts and patients' communication preferences, and the design of new, ICF-oriented assessment instruments.  相似文献   
83.
To identify neuroprotective changes in gene expression, we developed a neonatal mouse model of moderate to severe oxidative brain injury and hypothesized that recombinant erythropoietin (rEpo) would decrease the expression of proapoptotic and proinflammatory genes 24 and 48 h, respectively, after injury and increase the expression of neurogenic and angiogenic genes 168 h after injury. Postnatal day 10 BALB-c mice underwent sham surgery or right common carotid artery occlusion followed by alternating hypoxia and hyperoxia and were then treated with rEpo (5,000 U/kg s.c.) or saline (vehicle) daily for up to three doses. At death, gross brain injury was assessed, then hippocampus, cortex, and thalamus were isolated for RNA or protein extraction. Microarray analysis, real-time polymerase chain reaction, and Bio-Plex suspension array system validation were performed. rEpo decreased both incidence and severity of brain injury (median injury score 3 vs. 0, p < 0.0001) and reduced the injury-induced increases in interleukin-1alpha and interleukin-6 gene expression (p < 0.001), with corresponding effects on protein translation. Similarly, the expression of caspase-1, caspase-4, and caspase-6 and of p53 was increased by brain injury at 24 h, but mitigated by rEpo (p < 0.01). The interleukin-10 expression was higher in the rEpo-treated animals. Apoptotic and proinflammatory gene expression persisted for 168 h. There was no increase in angiogenic gene expression at the time points studied.  相似文献   
84.
Small, volatile hydrocarbons, including trichloroethylene, vinyl chloride, carbon tetrachloride, benzene, and chloroform, are common environmental pollutants that pose serious health effects. We have developed transgenic poplar (Populus tremula x Populus alba) plants with greatly increased rates of metabolism and removal of these pollutants through the overexpression of cytochrome P450 2E1, a key enzyme in the metabolism of a variety of halogenated compounds. The transgenic poplar plants exhibited increased removal rates of these pollutants from hydroponic solution. When the plants were exposed to gaseous trichloroethylene, chloroform, and benzene, they also demonstrated superior removal of the pollutants from the air. In view of their large size and extensive root systems, these transgenic poplars may provide the means to effectively remediate sites contaminated with a variety of pollutants at much faster rates and at lower costs than can be achieved with current conventional techniques.  相似文献   
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Objective To determine whether directly observed prostate-specific antigen (PSA) promoter diploid haplotype, either alone or in conjunction with androgen receptor (AR) genotype, is associated with prostate cancer risk. Methods We conducted a case–control study nested within the US population-based Cardiovascular Health Study cohort. Incident prostate cancers were identified by linkage to cancer registry records for the years 1989–2000. We genotyped 193 cases and 391 controls for the PSA −252 G/A and −158 G/A SNPs and the AR CAG microsatellite, and developed methods to directly determine proximal PSA promoter haplotypes. Exact logistic regression was used to estimate odds ratios and significance levels. Results No significant associations were observed between PSA diplotype and prostate cancer overall. Short (<20) AR CAG repeat lengths were associated with modest increases in the risk of prostate cancer (OR, 1.46; 95% CI, 0.97–2.19; p = 0.071) that were significant for advanced disease (OR, 1.82; 95% CI, 1.02–3.26; p = 0.044). Men who possessed two copies of the PSA*2 (−252G/−158G) haplotype and short AR CAG repeat lengths had a 4-fold (95% CI, 1.05–20.75; exact p = 0.040) increased risk of prostate cancer, and a 7-fold (95% CI, 1.25–39.78; exact p = 0.026) increased risk of advanced disease. Conclusions We found evidence that the PSA*2*2 diplotype in combination with short AR CAG alleles increases a man’s risk of developing prostate cancer. These findings support an etiologic role in prostate cancer of genetic interactions between polymorphisms that increase AR transactivation strength and those that alter the regulatory regions of target genes such as PSA that are responsive to androgen stimulation.  相似文献   
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The MAGEA gene family that encodes cancer testis antigens is differentially expressed in many cancers. Though MAGEA3 expression has been detected in gastrointestinal malignancies, its role in pancreatic ductal adenocarcinoma (PDAC) has not been well established. We assessed 57 patients who underwent intent-to-cure surgery for PDAC. Total RNA from paraffin-embedded pancreatic tumors was extracted and assessed for MAGEA3 gene expression by an optimized probe-based quantitative real-time RT-PCR (qRT) assay. MAGEA3 gene expression was detected by qRT in 25 (44%) patients. For the entire cohort, detection of MAGEA3 expression was associated with significantly decreased overall survival (median, 16 vs 33 months; log-rank, p = 0.032). When clinicopathologic factors, including age, gender, stage, tumor extent, lymph node metastasis, tumor grade, perineural invasion and lymphovascular invasion were assessed by univariate analysis, MAGEA3 gene expression and tumor grade were significant prognostic factors for poor survival (HR 2.1, 95% CI: 1.0-4.4, p = 0.041; and HR 3.7, 95% CI: 1.8-7.6, p = 0.0004, respectively). Immunohistochemistry (IHC) was performed and confirmed MAGEA3 protein in PDAC specimens. In conclusion, MAGEA3 is differentially expressed in patients with PDAC; its expression correlates with significantly worse survival. Molecular assessment for MAGEA3 should be considered to improve prognostic evaluation and to identify eligible patients for potential immune-based therapy.  相似文献   
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