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Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives.  相似文献   
163.
Cytomegalovirus (CMV) infection accelerates transplant vascular sclerosis (TVS) and chronic rejection (CR) in both human and animal solid organ transplantation models. The host/viral mechanisms involved in this process are unclear. We examine the role of the rat CMV (RCMV)-encoded chemokine-receptor R33 in the development of TVS using a rat heart transplantation/CR model. F344 heart grafts were transplanted heterotopically into Lewis recipients. The ability of RCMV lacking the R33 gene (RCMV-Deltar33) to accelerate CR/TVS (neointimal index, NI) was compared to wild-type (WT) RCMV. Allograft recipients were infected with 1 x 10(5) pfu RCMV or RCMV-Deltar33 on postoperative day (POD) 1. Grafts from RCMV-Deltar33-infected recipients demonstrated an accelerated time to allograft CR compared to grafts from uninfected recipients (POD = 56 vs. 90), this was slower than that seen in grafts from WT-RCMV-infected recipients (POD = 45). Similarly, the degree of graft TVS formation at terminal rejection in RMCV-Deltar33 infected recipients was more severe than uninfected recipients (NI = 63 vs. 45), yet not as severe as in WT-RCMV infected recipients (NI = 83). In parallel, RCMV-Deltar33 failed to induce vascular smooth muscle cell (SMC) migration in vitro, whereas WT-RCMV induced substantial migration. The RCMV-encoded chemokine-receptor r33 is critical for RCMV-accelerated TVS/CR and vascular SMC migration.  相似文献   
164.
BACKGROUND: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. METHODS: Twenty-one dogs with naturally occurring congestive heart failure and 21 age-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta and pulmonary artery. RESULTS: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (P < .003), lung (P < .0001), and kidney (P < .02); intimal-medial thickening in the pulmonary artery (P = .04); and fibrosis in the left ventricle (P < .0001) than control dogs. However, they did not have more plaque formation or intimal-medial thickening in the aorta than controls. There was significantly more arterial narrowing in papillary muscles than in all other locations in dogs with congestive heart failure (P < .002). In control dogs, arterial changes were less pronounced and did not differ in different locations. CONCLUSIONS: Dogs with naturally occurring myxomatous mitral valve disease have significantly more arterial changes in the myocardium, lung, and kidney, and significantly more fibrosis in the myocardium than control dogs. This could have important implications in the management of myxomatous mitral valve disease and raises interesting questions about the occurrence and importance of intramural small vessel disease in humans with primary mitral valve prolapse.  相似文献   
165.
Reconstruction of lateral skull base defects after tumor ablation.   总被引:1,自引:0,他引:1  
Neoplasms located in the lateral skull base region present a challenge for evaluation and management due to their difficult anatomic location and the complex reconstruction that is required following extensive tumor resection. Repair following tumor ablation requires a watertight dural seal, obliteration of the dead space, and coverage with vascularized soft tissue. Advances in radiologic imaging, diagnostic pathology, and surgical techniques and a multidisciplinary team for tumor ablation and reconstruction have significantly improved the treatment of these patients, minimized the occurrence of postoperative complications, and maximized patient outcome and quality of life. In this article, we present our experience in the reconstruction of extensive lateral skull base defects after tumor ablation.  相似文献   
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Over 800 Maine residents will be diagnosed with colorectal cancer (CRC) this year, and nearly 300 will die from the disease. While CRC screening can reduce these rates, it is only among insured populations that screening rates exceed 50%. This project aimed to reduce barriers to, and increase rates of CRC screening among underinsured and uninsured women, ages 50 years and over, residing in Cumberland County, Maine. The existing network of the Maine Breast and Cervical Health Program (MBCHP) was used to reach the target population. A packet containing (1) an offer for no-cost fecal occult blood test (FOBT) screening and CRC-related educational materials, and (2) a stamped, addressed postcard specifying the woman’s interest in these resources, was mailed to 300 MBCHP enrollees residing in Cumberland County. Women requesting screening were contacted by phone to further determine eligibility. Ninety-three women (31%) requested FOBT kits and 29 of these women requested educational materials. Ten women were ineligible for screening because of previous colonoscopy. Fifty-two completed FOBT kits (63%) were returned; all were negative. An additional 42 (14%) women requested educational materials only. To reduce the burden of CRC in Maine and nationally, disparate populations must be reached with efficient and effective screening services. Established networks are proven means for reaching uninsured and underinsured individuals with education, screening services, and necessary follow-up care. This project serves as a model for the future development of similar programs statewide and nationally.  相似文献   
169.
We compared short-term indicators for service mammography screening in Europe. Data were available from 17 programmes, although not all programmes provided a comprehensive reporting. More than 90% of the target population had been screened within the last 3 years in the WE trial, whereas only two-thirds of women in England and Copenhagen had been screened within the last 3 years, which will delay or reduce the effect of screening compared with the trial. Participation was highest in sparsely populated areas. Detection rates at first screen reached three times the baseline in Copenhagen, the Netherlands and North-West England. The clinical characteristics of screen-detected cases were badly reported. Given their importance for the long-term effect of screening, further data are warranted. Sensitivity and specificity could be measured only indirectly; they showed, however, considerable variation between programmes. Fyn, Florence and Stockholm had succeeded in combining high specificity with high sensitivity. With different recall policies, different proportions of women will experience a false-positive test; expected numbers after three screens were 14%, 10% and 1%, for England, Copenhagen and the Netherlands, respectively. Based on the observed wide variation in short-term indicators, a similar wide variation is expected in the effect of screening on breast cancer mortality.  相似文献   
170.
In aging brain, degenerative as well as compensatory regenerative processes are believed to occur. The neural cell adhesion molecule NCAM is involved in developmental and regenerative processes in the brain. However, the role of NCAM in aging brain has not been characterized. In this study, the expression of NCAM mRNAs and polypeptides was investigated in aging rat brain. The 7.4 and 6.7 kb NCAM mRNAs were selectively downregulated during postnatal development, and the 5.2 and 2.9 kb NCAM mRNAs were upregulated. However, from postnatal day 40 to old age no change in NCAM mRNA classes was observed. The fraction of NCAM mRNA containing the VASE exon increased postnatally but remained stable during adult life. VASE, which is believed to modulate the binding capacity, seemed to be relatively more abundant in the 7.4 and 6.7 kb NCAM mRNAs, encoding transmembrane NCAM forms, than in the 5.2 and 2.9 kb NCAM mRNAs, coding for glycosyl phosphatidylinositol (GPI) linked NCAM. Conversely, insertion of exons a and AAG between exons 12 and 13, a region containing two fibronectin type III repeats, seemed to be more pronounced in 5.2 and 2.9 kb NCAM mRNAs than in the 7.4 and 6.7 kb mRNAs. During postnatal development an increase in the fraction of 6.7 kb NCAM mRNA containing the exons a and AAG was observed. However, during aging the fraction of NCAM mRNAs containing this exon combination seemed constant. At the protein level, NCAM-A was downregulated both during development and aging. No changes were observed during aging in the composition of soluble NCAM forms in the brain, cerebrospinal fluid or blood plasma. The amount of NCAM in rat brain decreased during postnatal development, but remained at a constant level from postnatal day 40 to old age.To conclude, several changes in NCAM expression occur during early postnatal development emphasizing the important role of this molecule in the morphogenetic processes. During aging, a significant selective downregulation of NCAM-A was observed indicating that in general only minor regenerative processes occur in the brain.  相似文献   
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