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Clear cell ependymoma is a rare and diagnostically challenging subtype of ependymoma, whose genetic features are essentially unknown. We studied 13 clear cell ependymomas (five cases WHO grade II, eight cases WHO grade III) by comparative genomic hybridization (CGH). Chromosomal imbalances were found in 12/13 cases. The most common aberrations overall were +1q (38%), -9 (77%), -3 (31%), and -22q (23%). Clear cell ependymomas of WHO grade II were characterized by -9 (40%), whereas WHO grade III cases mainly showed +1q (63%), and +13q (25%), as well as -9 (100%), -3 (38%), and -22q (25%). In contrast to other ependymal tumors, clear cell ependymomas of WHO grade II showed fewer imbalances than WHO grade III samples (1.4 vs 3.5 per case). Although some of the implicated chromosomes have previously been shown to be involved in other ependymoma variants, the striking frequency of +1q, -9, and -3 suggests that aberrations differ between clear cell and other types of ependymomas, in particular, for loss of chromosome 9 which can be regarded as the molecular hallmark of clear cell ependymomas. 相似文献
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Richard Kitz Markus A. Rose Heidrun Schönborn Stefan Zielen Hans J. Böhles 《Pediatric allergy and immunology》2006,17(2):112-117
Polyunsaturated fatty acids (PUFAs) are components of cell membranes and may play an immunomodulating role in the pathogenesis of atopic dermatitis (AD). The goal was to determine the impact of PUFAs on AD by dietary supplementation of infants. Based on the parents' decision on their babies' primary feeding, mothers and newborns were randomized to the supplementation with gamma-linolenic acid (GLA) or placebo for up to 6 months. Breastfed infants received GLA by supplementing their mothers. Formula diet was commercial whey hydrolysate unsupplemented with PUFAs. Of 131 eligible infants, 24 developed AD within the first year of life. Of these, nine belonged to the exclusively breastfed group (n = 58), 14 to the combined-fed group (n = 53), and one to the never breastfed group (n = 20). We could not find an influence of GLA on the development of AD. In subjects with AD, at 1 yr of age the serum-immunoglobulin E (IgE) was the lowest in the GLA-supplemented group A-subjects. In the GLA-supplemented group, GLA-levels in breast milk were similar in atopic and non-atopic infants. In the non-supplemented group the GLA-content of breast milk was 0.07% of total fatty acids in atopic infants vs. 0.17% in non-atopic infants (p < 0.01). Dietary GLA-supplementation could not prevent AD. Interestingly, the number of infants developing AD was the lowest in never breastfed children. In infants suffering from AD, GLA-supplementation seemed to reduce total IgE in the first year of life. 相似文献
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Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. 总被引:21,自引:0,他引:21
Heike A Bischoff Hannes B St?helin Walter Dick Regula Akos Margrith Knecht Christian Salis Matthias Nebiker Robert Theiler Michael Pfeifer Bettina Begerow Robert A Lew Martin Conzelmann 《Journal of bone and mineral research》2003,18(2):343-351
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function. 相似文献
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