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31.
Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
32.
Many nuclear components participating in related pathways appear concentrated in specific areas of the mammalian nucleus. The importance of this organization is attested to by the dysfunction that correlates with mis-localization of nuclear proteins in human disease and cancer. Determining the sub-nuclear localization of proteins is therefore important for understanding genome regulation and function, and it also provides clues to function for novel proteins. However, the complexity of proteins in the mammalian nucleus is too large to tackle this on a protein by protein basis. Large-scale approaches to determining protein function and sub-cellular localization are required. We have used a visual gene trap screen to identify more than 100 proteins, many of which are normal, located within compartments of the mouse nucleus. The most common discrete localizations detected are at the nucleolus and the splicing speckles and on chromosomes. Proteins at the nuclear periphery, or in other nuclear foci, have also been identified. Several of the proteins have been implicated in human disease or cancer, e.g. ATRX, HMGI-C, NBS1 and EWS, and the gene-trapped proteins provide a route into further understanding their function. We find that sequence motifs are often shared amongst proteins co-localized within the same sub-nuclear compartment. Conversely, some generally abundant motifs are lacking from the proteins concentrated in specific areas of the nucleus. This suggests that we may be able to predict sub-nuclear localization for proteins in databases based on their sequence.  相似文献   
33.
There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.   相似文献   
34.
Seventy-four families of probands with oculoauriculovertebral anomaly were evaluated, including 116 parents and 195 off-spring. Relatives were examined to identify ear malformations, mandibular anomalies, and other craniofacial abnormalities. For segregation analysis using POINTER, selection of the sample was consistent with single as-certainment. Different population liabilities were used for probands and relatives, because affection was narrowly defined for probands and broadly defined for relatives. The hypothesis of no genetic transmission was rejected. The evidence favored autosomal dominant inheritance; recessive and polygenic models were not distinguishable. © 1992 Wiley-Liss, Inc.  相似文献   
35.
Eighty-four cases of extraosseous Ewing's sarcoma (EOE) were found during the pathology review of the Intergroup Rhabdomyosarcoma Study I and II. Patients commonly presented during or after adolescence with the most common primary sites including the trunk, extremities, and retroperitoneum. Males were slightly more affected. Histologic sections of 74 tumors in the pathology repository were re-reviewed with attention to rosette formation (positive in 18 cases) and glycogen deposition (++ in 21, + in 36, +/- in 11, and - in 2 of 70 cases examined). Fourteen tumors (7 with rosettes and 7 without) were selected for immunohistochemical and ultrastructural studies, and 13 showed single or multiple neural markers (neuron-specific enolase in 8, S-100 protein in 6, and neurosecretory-type granules in 9). These possible cases of neural EOE could be divided into three subgroups: tumor with bidirectional neuroblastic and schwannian differentiation (5 cases), tumor with monodirectional neuroblastic differentiation (7 cases), and tumor with monodirectional schwannian differentiation (1 case). EOE with a neural nature may be categorized into a spectrum of peripheral primitive neuroectodermal tumors. Clinical, histopathologic, and biologic differences between this disease and conventional sympathetic neuroblastoma are discussed.  相似文献   
36.
Microbial infections,immunomodulation, and drugs of abuse   总被引:12,自引:0,他引:12  
The use of recreational drugs of abuse has generated serious health concerns. There is a long-recognized relationship between addictive drugs and increased levels of infections. Studies of the mechanisms of actions of these drugs became more urgent with the advent of AIDS and its correlation with abused substances. The nature and mechanisms of immunomodulation by marijuana, opiates, cocaine, nicotine, and alcohol are described in this review. Recent studies of the effects of opiates or marijuana on the immune system have demonstrated that they are receptor mediated, occurring both directly via specific receptors on immune cells and indirectly through similar receptors on cells of the nervous system. Findings are also discussed that demonstrate that cocaine and nicotine have similar immunomodulatory effects, which are also apparently receptor mediated. Finally, the nature and mechanisms of immunomodulation by alcohol are described. Although no specific alcohol receptors have been identified, it is widely recognized that alcohol enhances susceptibility to opportunistic microbes. The review covers recent studies of the effects of these drugs on immunity and on increased susceptibility to infectious diseases, including AIDS.  相似文献   
37.
38.
Transposable elements (TEs) comprise a major component of eukaryotic genomes, and exhibit striking deviations from random distribution across the genomes studied, including humans, flies, nematodes, and plants. Although considerable progress has been made in documenting these patterns, the causes are subject to debate. Here, we use the genome sequence of Arabidopsis thaliana to test for the importance of competing models of natural selection against TE insertions. We show that, despite TE accumulation near the centromeres, recombination does not generally correlate with TE abundance, suggesting that selection against ectopic recombination does not influence TE distribution in A. thaliana. In contrast, a consistent negative correlation between gene density and TE abundance, and a strong under-representation of TE insertions in introns suggest that selection against TE disruption of gene expression is playing a more important role in A. thaliana. High rates of self-fertilization may reduce the importance of recombination rate in genome structuring in inbreeding organisms such as A. thaliana and Caenorhabditis elegans.  相似文献   
39.
PURPOSE: Recent reports on medical students' career choices suggest that lifestyle increasingly influences career decisions. The authors addressed the changing influence of lifestyle and income on career choice, how these influences differ by specialty, and the specific careers students identify as lifestyle friendly. METHOD: From 1998 to 2004, 1,334 (73%) fourth-year medical students from Brody School of Medicine at East Carolina University (no. = 485 graduates) and New York Medical College (no. = 1,348 graduates) completed a questionnaire that addressed career specialty preferences, as well as income and lifestyle concerns. Students were asked to rate career choice influences on a four-point scale (1 = no influence, 4 = major influence). Factor analysis of these influences identified seven factors including one each for lifestyle and income. RESULTS: A total of 1,327 students indicated a career preference. Lifestyle (p = .018) and income (p = .011) were found to increasingly influence medical students' career choices during the study period. Overall, the authors found significant differences between specialties in the relative contribution of these factors. Students' perceptions of specialties existed on a continuum of lifestyle friendly (e.g., radiology) to lifestyle unfriendly (e.g., obstetrics-gynecology). Contrary to previous reports, the students' responses indicate they perceived the primary care specialties as lifestyle intermediate compared to other specialties. CONCLUSIONS: Lifestyle and income have become more important to medical students in their career choice, and the relative influence of these factors varies considerably between specialties. This study suggests that previous efforts to dichotomize careers into those with controllable and uncontrollable lifestyles may mask important complexities.  相似文献   
40.
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