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31.
Varma G Varma R Huang H Pryshchepava A Groth J Fleming D Nowak NJ McQuaid D Conroy J Mahoney M Moysich K Falkner KL Geradts J 《British journal of cancer》2005,93(6):699-708
High-resolution array comparative genomic hybridisation (aCGH) analysis of DNA copy number aberrations (CNAs) was performed on breast carcinomas in premenopausal women from Western New York (WNY) and from Gomel, Belarus, an area exposed to fallout from the 1986 Chernobyl nuclear accident. Genomic DNA was isolated from 47 frozen tumour specimens from 42 patients and hybridised to arrays spotted with more than 3000 BAC clones. In all, 20 samples were from WNY and 27 were from Belarus. In total, 34 samples were primary tumours and 13 were lymph node metastases, including five matched pairs from Gomel. The average number of total CNAs per sample was 76 (range 35-134). We identified 152 CNAs (92 gains and 60 losses) occurring in more than 10% of the samples. The most common amplifications included gains at 8q13.2 (49%), at 1p21.1 (36%), and at 8q24.21 (36%). The most common deletions were at 1p36.22 (26%), at 17p13.2 (26%), and at 8p23.3 (23%). Belarussian tumours had more amplifications and fewer deletions than WNY breast cancers. HER2/neu negativity and younger age were also associated with a higher number of gains and fewer losses. In the five paired samples, we observed more discordant than concordant DNA changes. Unsupervised hierarchical cluster analysis revealed two distinct groups of tumours: one comprised predominantly of Belarussian carcinomas and the other largely consisting of WNY cases. In total, 50 CNAs occurred significantly more commonly in one cohort vs the other, and these included some candidate signature amplifications in the breast cancers in women exposed to significant radiation. In conclusion, our high-density aCGH study has revealed a large number of genetic aberrations in individual premenopausal breast cancer specimens, some of which had not been reported before. We identified a distinct CNA profile for carcinomas from a nuclear fallout area, suggesting a possible molecular fingerprint of radiation-associated breast cancer. 相似文献
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Cowell JK Matsui S Wang YD LaDuca J Conroy J McQuaid D Nowak NJ 《Cancer Genetics and Cytogenetics》2004,151(1):36-51
Identification of genetic losses and gains is valuable in analysis of brain tumors. Locus-by-locus analyses have revealed correlations between prognosis and response to chemotherapy and loss or gain of specific genes and loci. These approaches are labor intensive and do not provide a global view of the genetic changes within the tumor cells. Bacterial artificial chromosome (BAC) arrays, which cover the genome with an average resolution of less than 1 MbP, allow defining the sum total of these genetic changes in a single comparative genomic hybridization (CGH) experiment. These changes are directly overlaid on the human genome sequence, thus providing the extent of the amplification or deletion, reflected by a megabase position, and gene content of the abnormal region. Although this array-based CGH approach (CGHa) seems to detect the extent of the genetic changes in tumors reliably, it has not been robustly tested. We compared genetic changes in four newly derived, early-passage glioma cell lines, using spectral karyotyping (SKY) and CGHa. Chromosome changes seen in cell lines under SKY analysis were also detected with CGHa. In addition, CGHa detected cryptic genetic gains and losses and resolved the nature of subtle marker chromosomes that could not be resolved with SKY, thus providing distinct advantages over previous technologies. There was remarkable general concordance between the CGHa results comparing the cell lines to the original tumor, except that the magnitude of the changes seen in the tumor sample was generally suppressed compared with the cell lines, a consequence of normal cells contaminating the tumor sample. CGHa revealed changes in cell lines that were not present in the original tumors and vice versa, even when analyzed at the earliest passage possible, which highlights the adaptation of the cells to in vitro culture. CGHa proved to be highly accurate and efficient for identifying genetic changes in tumor cells. This approach can accurately identify subtle, novel genetic abnormalities in tumors directly linked to the human genome sequence. CGHa far surpasses the resolution and information provided by conventional metaphase CGH, without relying on in vitro culture of tumors for metaphase spreads. 相似文献
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There are many obstacles in undertaking psychological burns research with children and adolescents, and the more useful longitudinal studies are particularly fraught with difficulty. This work introduces and discusses the problems of attrition and nonparticipation encountered in our attempt to use a rigorous design and methodology to study this population. The aim is to provide the impetus for a more thorough, detailed review of this problem. 相似文献
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Robinson SK McQuaid JR Viirre ES Betzig LL Miller DL Bailey KA Harris JP Perry W 《The international tinnitus journal》2003,9(2):97-103
Twenty percent of people endure tinnitus to a degree that their quality of well-being and productivity in life are impaired, and up to 60% report depression. Four measures are widely used to assess tinnitus-related distress, yet the relationship among all four measures or their relationship to relevant psychiatric variables has yet to be studied. This study assessed the association between the four commonly used measures of tinnitus and their relationship to depressive symptoms, quality of well-being, and internal focus. Sixty-five people with tinnitus completed the following measures: Iowa Tinnitus Handicap Questionnaire (THQ); Tinnitus Reaction Questionnaire (TRQ); Tinnitus Handicap Inventory (THI); Tinnitus Questionnaire (TQ); Hamilton Rating Scale for Depression (HRSD); Beck Depression Inventory (BDI); Quality of Well-Being Scale (QWBS); Modified Somatic Perception Questionnaire (MSPQ); and Private Self-Consciousness Scale (PSCS). All the tinnitus measures were highly intercorrelated (r = .76-.90; all p values < .001), and related to depressive symptoms (r = .48-.66; p < .001) and QWBS (r = .37-.48; all p values < 0.008). The tinnitus measures correlated with the MSPQ (r = .37-.52; all p values < .01) but not with the PSCS. When controlling for the shared variance between tinnitus measures, the THQ independently predicted the HRSD, whereas the TRQ independently predicted the BDI. 相似文献
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Parathyroid adenomas evaluated by Tl-201/Tc-99m pertechnetate subtraction scintigraphy and high-resolution ultrasonography 总被引:2,自引:0,他引:2
Winzelberg GG; Hydovitz JD; O'Hara KR; Anderson KM; Turbiner E; Danowski TS; Lippe RD; Melada GA; Harrison AM 《Radiology》1985,155(1):231-235
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar. 相似文献
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