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71.
OBJECTIVES/HYPOTHESIS: Tumor progression has been attributed to the accumulation of DNA damage concurrent with selection of advantageous mutations; this DNA damage may result from failure to maintain genomic integrity or from susceptibility to carcinogens. Glutathione S-transferases (GSTs), enzymes that metabolize many carcinogens, may play a role in preserving genome integrity. The objectives of this study are to assess the relationship of GST genotypes with prognosis, clinicopathologic parameters, and genomic instability in papillary thyroid cancer. STUDY DESIGN: Prospective analysis. METHODS: GSTM1 and GSTT1 genotypes of 35 matched normal and papillary thyroid cancer specimens were determined by polymerase chain reaction (PCR) using primers specific for the coding sequences of each gene. Genomic instability was measured by intersimple sequence repeat PCR for each tumor/normal pair and compared with the GAMES prognostic scoring system and clinicopathologic parameters including age, extrathyroidal extension, tumor grade, size, stage metastasis, sex, and smoking history. RESULTS: GSTM1 and GSTT1 null genotypes were found in the normal tissues of 46% and 45%, respectively. No gene losses were detected in the tumor specimens. A significant association between the GSTM1 null genotype and increased risk of recurrence and death was observed. Elevated GII correlated with smoking and tumor stage but not with GST genotype. CONCLUSION: The association of GSTM1 null genotype with intermediate and high risk GAMES categories suggests that GSTM1 provides some protection against disease progression. However, this protection does not confer resistance to disease onset. GST genotyping may be a useful adjunct prognosticator with GAMES.  相似文献   
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The age of onset of motor neuron disease in Cu/Zn superoxide dismutase 1 (SOD1) mutation carriers are variable, commencing at any time from the second decade. The authors performed a retrospective analysis of family information in pedigrees dating back to the 1780s, to determine the age-dependent penetrance of three different SOD1 mutations: Glu100Gly, Ile113Thr, and Val148G1y. The penetrance of symptomatic MND in these three SOD1 mutations was greater than 95% by the age of 78. The affected family members with the Val148Gly mutation had the worst prognosis, with a mean age of death of 46.1 years, compared to 54.2 years for the Glu100Gly mutation and 59.9 years for Ile113Thr mutation. Kaplan-Meier survival curves showed that survival of the 3 SOD1 mutation families, when combined, was reduced by nearly 10 years with the mean age of death for all SOD1 mutation carriers being 52.6 years compared to 62.5 years for the control individuals. The SOD1 mutation group also resulted in earlier death compared to sporadic MND, which from natural history studies is 61.4 years. This may reflect that the SOD1 mutation is associated with more progressive and rapid disease, as the age of onset of disease was not earlier. This information would have important implications for genetic counseling of members of individual SOD1 mutation carrier families.  相似文献   
74.
OBJECTIVES: To determine the host genes that govern susceptibility to recurrent respiratory papillomatosis (RRP). RRP is caused by human papillomavirus (HPV) 6 and 11. Millions of babies are exposed during the birthing process, but relatively few develop the disease and the aggressiveness of the course is highly variable. Genetically encoded host susceptibility is postulated. Determining the host genes that govern susceptibility will enhance our understanding not only of RRP but also of host-viral interaction in general. STUDY DESIGN: A genome-wide association study on familial triads consisting of an RRP-affected child and his or her parents. Using the HapMap data from the human genome project, we will identify those alleles that are over-transmitted by the parents to their affected offspring as compared to those alleles that are under-transmitted. METHODS: Approximately 400 patients and their parents will be recruited through a collaboration between the Center for Genomic Sciences and the RRP Task Force. DNA will be extracted from blood specimens and viral typing will be performed on biopsy specimens. Patients will be genotyped using single nucleotide polymorphism (SNP) markers and compared to their respective parents' genotype using the transmission disequilibrium test. Both a genome scan and a candidate gene approach will be utilized.RESULTS Institutional Review Board authorization has been obtained at three hospitals and the process is underway at 18 more. Patient and parent recruitment has begun. Specimens have been forwarded to Pittsburgh, Pennsylvania, where the DNA has been extracted and is being stored. CONCLUSIONS: A novel approach combining a nationwide patient resource and the mapping power of the sub-centimorgan human haplotype map has been developed to elucidate the biological mechanisms of RRP by determining the genetically encoded susceptibilities of host-virus interaction.  相似文献   
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The brain has been shown to honor the fundamental linguistic difference between semantic and syntactic information. Here we demonstrate that it even further indicates the necessity to distinguish between two differential syntactic processes: that is to say between the processing of phrase structure information necessary to build up syntactic structures on-line and verb argument structure information crucial to build up representations of who is doing what to whom. The former process is reflected in the event-related brain potentials (ERPs) as an anterior negativity followed by a late centro-parietal positivity, whereas the latter process is reflected as a centro-parietal negativity–positivity pattern. The different ERP patterns clearly suggest that the theoretically assumed difference between local syntactic structure building and argument structure processing is neurophysiologically real.  相似文献   
78.
Prostatic adenocarcinoma (PAC) is a multifocal disease. In this study, we identified isolated and small foci of PAC (ISPAC) in radical prostatectomy specimens, described the histopathologic features, investigated their zonal distribution in the prostate and their relationship with large tumor nodules, and correlated the findings with those of preceding biopsy cores. One hundred and thirty radical prostatectomy specimens performed for PAC or for urothelial carcinoma of the urinary bladder with incidental PAC were reviewed for identification of ISPAC. Prostates were serially sectioned in the horizontal plane and submitted in toto for microscopic examination. ISPAC were defined as foci of PAC measuring less than 3 mm in maximum diameter. There were 461 ISPAC identified in 114 cases. They were distributed in the transitional zone (TZ) (18 foci), the apex (73 foci), the anterior horn of the non-TZ (NTZ) (118 foci), the base (8 foci), and the remaining NTZ (244 foci). ISPAC usually consisted of groups of small acini with a GS ranging from 2 to 7 (3 + 4). GSs of ISPAC consisted of single grade or two consecutive grades equal to or lower than those of the main PAC. ISPAC were more often located in close proximity to large tumor nodules. The number of ISPAC increased with the tumor volume up to 3 cm3, then decreased as the PAC became more extensive (p value = 0.02, statistically significant). Prostates with NTZ PAC <1.5 cm3 and TZ PAC or prostates containing 4 or more than 4 ISPAC tended to be frequently associated with small foci of PAC in biopsy cores In this study, we identified ISPAC that likely represent foci of PAC in early development and account for the multicentricity and heterogeneity of PAC. ISPAC in the NTZ were common and may account for small foci of PAC or atypia in biopsy cores. Although these small foci of PAC or atypia in biopsy cores without accompanying higher GS PAC were often associated with significant PAC, they may also occasionally represent insignificant or vanishing PAC in subsequent radical prostatectomies.  相似文献   
79.
Dickinson G 《CJEM》2002,4(5):371
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80.
During the last decade of the twentieth century there was a proliferation of laparoscopic surgical procedures. This has been credited with significantly improving the care and outcomes of surgical patients, despite the presence of little evidence to support such claims. Many laparoscopic procedures have developed due to the perception that they are better; however, this perception was not and is not supported by level one data (randomised controlled trial). It is hard to obtain level one data to validate the perception of advantage once a technique has become fully established. At the same time that laparoscopic surgery was developing, many other aspects of peri-operative care changed that influenced outcomes. These changes may account for many of the benefits claimed by laparoscopic surgery.  相似文献   
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