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71.
Crystal deposits in the human intervertebral disc: implications for disc degeneration. 总被引:1,自引:0,他引:1
BACKGROUND CONTEXT: Although crystal deposition in cartilage and synovial fluid has received much attention, crystal formation and the role that crystal deposits play are virtually unexplored in the intervertebral disc. In articular cartilage matrix, crystal deposits are associated with altered extracellular matrix (ECM) and cell phenotypic features, but crystal deposition in the human intervertebral disc has received much less attention. PURPOSE: To determine the incidence of crystal deposits in the annulus and to evaluate associated disc cell and ECM features. STUDY DESIGN/SETTING: Human intervertebral disc annulus tissue was obtained in a prospective study of the presence of crystals in the disc ECM. Human Subjects Institutional Review Board approved experimental studies. PATIENT SAMPLE: Two hundred eight sequential disc specimens were submitted from surgical disc procedures performed on individuals with herniated discs, degenerative disc disease, or recurrent disc herniation. During this same time period, three disc specimens were received from nonsurgical donors and added to the study population. OUTCOME MEASURES: Histologic features with special attention to crystal deposition. METHODS: Specimens were processed undecalcified and examined for the histologic presence of crystal deposits and ECM features around the crystals. RESULTS: The proportion of specimens containing crystals was determined to be 14.7%; crystals displayed varying sizes, morphology, and polarized light birefringence features. Pyrophosphate crystals were most common, but oxalate-like crystals were also present. ECM in crystal regions showed previously recognized alterations. CONCLUSIONS: This study shows that the incidence of crystal deposits in discs is approximately 15% and is thus a relatively common occurrence. These data are important because masses of crystals not only disrupt disc ECM but may also accelerate preexisting degenerative changes via an elevation in matrix metalloproteinases (as previously recognized in cartilage). Because failure of the structural integrity of the disc can result in annular tears and subsequent disc herniation, the mechanisms of crystal formation and the relationship between crystals and disc degeneration merit further investigations. 相似文献
72.
Lorraine N Clark Eneli Haamer Helen Mejia-Santana Juliette Harris Suzanne Lesage Alexandra Durr Sabine Janin Bs Katja Hedrich Elan D Louis Lucien J Cote Howard Andrews Stanley Fahn Cheryl Waters Blair Ford Steven Frucht William Scott Christine Klein Alexis Brice Hanno Roomere Ruth Ottman Karen Marder 《Movement disorders》2007,22(7):932-937
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
73.
Sharon A Cook Robert Rosser Helen Toone M Ian James Peter Salmon 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(1):54-64
PURPOSE: Elective cosmetic surgery is expanding in the UK in both the public and private sectors. Because resources are constrained, many cosmetic procedures are being excluded within the National Health Service. If guidelines on who can receive such surgery are to be evidence-based, information is needed about the level of dysfunction in patients referred for elective surgery and whether this is related to their degree of physical abnormality. METHOD: Consecutive patients referred to a regional plastic surgery and burns unit for assessment for elective cosmetic surgery completed standardised measures of physical and psychosocial dysfunction, and indicated their perception of the degree of their abnormality and their preoccupation with it. We distinguished between patients referred for physical reasons or appearance reasons only, and compared levels of physical and psychosocial dysfunction in each with published values for community and clinical samples. Surgeons indicated patients' degree of objective abnormality, and we identified the relationship of dysfunction with perceived and objective abnormality and preoccupation. RESULTS: Whether patients sought surgery for physical or appearance reasons, physical function was normal. Those seeking surgery for appearance reasons only had moderate psychosocial dysfunction, but were not as impaired as clinical groups with psychological problems. Patients seeking the correction of minor skin lesions for purely appearance reasons reported excellent physical and psychosocial function. Level of function was related (negatively) to patients' preoccupation with abnormality rather than to their perceived or objective abnormality. CONCLUSIONS: In general, patients referred for elective cosmetic surgery did not present with significant levels of dysfunction. Moreover, levels of functioning were related to preoccupation rather than to objective abnormality. Therefore, for most patients, whether surgical treatment is generally appropriate is questionable. Future guidelines must seek to identify the small minority who do have a clinical need for surgery. 相似文献
74.
Vinay Puri Andrew McQuillin Khalid Choudhury Susmita Datta Jonathan Pimm Srinivasa Thirumalai Robert Krasucki Jacob Lawrence Digby Quested Nicholas Bass Helen Moorey Jenny Morgan Bhaskar Punukollu Gomathinayagam Kandasami David Curtis Hugh Gurling 《Neuropsychopharmacology》2007,61(7):873-879
BACKGROUND: Linkage studies by us and others have confirmed that chromosome 1q23.3 is a susceptibility locus for schizophrenia. Based on this information, several research groups have published evidence that markers within both the RGS4 and CAPON genes, which are 700 kb apart, independently showed allelic association with schizophrenia. Tests of allelic association with both of these genes in our case control sample were negative. Therefore, we carried out further fine mapping between the RGS4 and CAPON genes. METHODS: Twenty-nine SNP and microsatellite markers in the 1q23.3 region were genotyped in the United Kingdom based sample of 450 cases and 450 supernormal control subjects. RESULTS: We detected positive allelic association after the eighth marker was genotyped and found that three microsatellite markers (p = .011, p = .014, p = .049) and two SNPs (p = .004, p = .043) localized in the 700 kb region between the RGS4 and CAPON genes, within the UHMK1 gene, were associated with schizophrenia. Tests of significance for marker rs10494370 remained significant following Bonferroni correction (alpha = .006) for multiple tests. Tests of haplotypic association were also significant for UHMK1 (p = .009) using empirical permutation tests, which make it unnecessary to further correct for both multiple alleles and multiple markers. CONCLUSIONS: These results provide preliminary evidence that the UHMK1 gene increases susceptibility to schizophrenia. Further confirmation in adequately powered samples is needed. UHMK1 is a serine threonine kinase nuclear protein and is highly expressed in regions of the brain implicated in schizophrenia. 相似文献
75.
76.
Changes in the design of hospital wards have usually been determined by architects and members of the nursing and medical professions, the views and preferences of patients have seldom been sought directly The Hospital Anxiety and Depression scale and the Disturbance Due to Hospital Noise questionnaire were administered to 64 female patients on bay and Nightingale wards together with a questionnaire designed for this study Perceptions of social and physical factors of ward design were examined, and their relationship to psychological well-being and sleep patterns The results show that the bay ward seemed to offer a more favourable environment for patients but some of the disadvantages of bay wards are balanced by better staffing levels and better and more modern facilities Visibility to nurses was lower on the bay ward The Nightingale ward was perceived as significantly noisier than the bay ward and noise levels were significantly correlated to anxiety scores Paradoxically the increase in noise levels appeared to improve the perceived level of privacy on the Nightingale ward Seventy-five per cent of patients were found to prefer the bay ward design, and since neither design appears to have major disadvantages their continued introduction should be encouraged However, recommendations are made concerning the optimizing of patients' well-being within the bay ward setting 相似文献
77.
78.
Michael V. Hansen Helen Holmgren Anders Spberg Andrej Warycha 《Neurourology and urodynamics》1990,9(3):257-268
EMG responses in the external anal sphincter (EAS), the rectus abdominis muscle (RA), and the anterior tibial muscle (TA) were recorded following single magnetic transcranial cortical stimulations (TCCS) in seven healthy volunteers. The responses in the EAS differed from the responses in the other muscles. They had comparatively long durations ranging from 1 to 2 seconds, no inhibitory periods were observed, and there was no tendency for habituation to occur following a limited number of stimuli. The responses recorded in the EAS were used as test responses in order to evaluate the excitability changes in the EAS motoneurons occurring during bladder filling. Cystometries with filling rates of 15, 50 and 200 ml/min were done. During these cystometries TCCS were applied repeatedly, with constant strength, after each 50 ml of filling up to bladder capacity. The responses following TCCS changed in a highly reproducible way during bladder filling. After 100–200 ml of filling, the responses had longer latencies, diminished sizes, and shorter durations. When the filling reached a level 50–150 ml below capacity, the responses in most subjects again became greater and the latencies shorter. The changes were believed to be physiological. It was concluded that the EAS motoneurons are under both inhibitory and facilitatory influence during bladder filling in intact healthy humans. Facilitatory influences are often observed when the bladder is filled close to capacity. At lower bladder volumes the observed influence is always inhibitory. A decrease in the EMG activity of the EAS during filling cystometry should consequently not be regarded as a pathological response. 相似文献
79.
80.