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41.
Chromosome 11q13 markers and D-type cyclins in breast cancer 总被引:7,自引:0,他引:7
Gordon Peters Vera Fantl Rosalind Smith Sharon Brookes Clive Dickson 《Breast cancer research and treatment》1995,33(2):125-135
Summary One in six primary human breast cancers has DNA amplification centered on the cyclin D1 gene (CCND1) on chromosome 11q13. This genetic abnormality is preferentially associated with estrogen-receptor positive tumors and may define a sub-class of patients with an adverse prognosis. AlthoughCCND1 has the credentials of a cellular oncogene, being a target for chromosomal translocation and retroviral integration, the 11q13 amplicon encompasses several other markers andCCND1 is not the only candidate for the key gene on the amplified DNA. To assess their relative importance, we have constructed a physical map of the amplified DNA and compared the extent and frequency of amplification across the region. Since it is likely that the gene providing the selective force for amplification will be expressed at elevated levels, we have also examined expression of both RNA and protein. By these criteria, cyclin D1 remains the strongest candidate for the key oncogene on the amplicon and we are currently investigating the functional consequences of its over-expression.Presented by Gordon Peters at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer. 相似文献
42.
Intra-anal intussusception was diagnosed in eight of 39 patients on evacuation proctography. Posteroanterior views revealed prolapse of the infolded rectum into the anal canal on straining in seven of eight patients, associated with splaying open of the anal canal and sudden distal movement of the fold during prolapse. Similar changes were seen in four of 31 patients in whom intussusception had not been diagnosed on lateral evacuation proctography. The pattern of the collapsed rectum was assessed for fold length, thickness, and angulation in relation to the midline of the rectum. Infoldings that prolapsed were closer to the anorectal junction on stress (mean 14.6 42.4 mm, p < 0.0001) showed greater change in height between rest and strain (28.8 14.6 mm, p < 0.05) and became more acutely angled during straining (41.9 5.3°, p < 0.01). Intra-anal intussusception may be missed in 33% (four of 12 patients) on routine evacuation proctography. Posteroanterior stress proctography is a simple supplementary examination to validate intussusception. 相似文献
43.
Several factors which affect bone density and predict risk of osteoporosis (e.g., ethnic origin, amenorrhea) are reportedly associated with a higher incidence of stress fracture in active premenopausal women. The authors surveyed 2,312 active duty Army women for the prevalence of ever having been diagnosed ("told by a doctor") with a stress fracture (16.1% of respondents) and examined the relationship between surveyable risk factors for low bone density and this self-reported stress fracture history (self-reported SF). Current smoking, previous history of amenorrhea (menses absent greater than 6 months), and known family history of osteoporosis were significantly associated with self-reported SF, while black ethnic origin was a protective factor. These data suggest hypotheses of stress fracture pathogenesis in Army women which bear further testing. 相似文献
44.
Dean PG van Heerden JA Farley DR Thompson GB Grant CS Harmsen WS Ilstrup DM 《World journal of surgery》2000,24(11):1437-1441
Multiple endocrine neoplasia type I (MEN-I) is an autosomal dominant disorder characterized by endocrinopathies involving
the anterior pituitary gland, parathyroid glands, and pancreas. The long-term prognosis for patients affected with this disorder
is uncertain. To better characterize this prognosis, we performed a retrospective review of all patients with MEN-I treated
at a single institution during the period 1951–1997. A group of 233 patients served as the study population. Their records
were analyzed for confirmation of diagnosis, treatments received, long-term survival, and cause of death. Altogether, 108
eight male patients (46%) and 125 female patients (54%) were identified. At the conclusion of the study, 164 (70%) were alive
and 69 (30%) were deceased, with a median follow-up for patients alive at last contact of 13.4 years (range < 1 month to 54.3
years). The cause of death was reliably obtained in 60 patients. Of these patients, 17 (28%) died of causes related to MEN-I,
most commonly metastatic islet cell tumors (10 patients). The remaining patients died of causes unrelated to MEN-I, most commonly
coronary artery disease and nonendocrine malignancies (14% each). The overall 20-year survival of MEN-I patients was 64% (95%
CI was 56–72%), and that of an age- and gender-matched upper Midwest population was 81% (p < 0.001). Patients with MEN-I appear to be at increased risk of premature death. Earlier diagnosis and treatment of potentially
malignant pancreatic islet cell neoplasms may result in a decrease of this premature mortality. 相似文献
45.
目的 建立一种快速有效的分析方法 ,达到鉴定淫羊藿及人参复方产品中黄酮苷类及人参皂苷类成分 ,并测定各成分含量的目的 ,最终控制复方中淫羊藿及人参的比例。方法 通过反相液相色谱 ,对包括药典所收载的淫羊藿药材及其产品进行分析。淫羊藿中的主要黄酮苷类成分 ,以淫羊藿定A、淫羊藿定B、淫羊藿定C、淫羊藿苷为对照品 ;对主要的人参皂苷类成分 ,以人参皂苷Rg1 、Re、Rf、Rb1 、Rb2 、Rd为对照品。结果 在同一色谱条件下 ,对主要黄酮苷类及人参皂苷类成分均可同时测定且分离良好。结论 该方法适用于淫羊藿、人参及其复方产品中淫羊藿黄酮苷类、人参皂苷类成分的定性、定量分析 相似文献
46.
Osteoblast-derived factors induce androgen-independent proliferation and expression of prostate-specific antigen in human prostate cancer cells. 总被引:1,自引:0,他引:1
47.
Productive infection of primary human endothelial cells by pig endogenous retrovirus (PERV) 总被引:12,自引:1,他引:11
Martin U Winkler ME Id M Radeke H Arseniev L Takeuchi Y Simon AR Patience C Haverich A Steinhoff G 《Xenotransplantation》2000,7(2):138-142
Abstract: The potential risk of viral transmission in the setting of xenotransplantation has gained major attention. Different porcine cell types have been shown to release retroviral particles, which are infectious for human cell lines in vitro. However, there are only a few data on whether PERV (pig endogenous retrovirus) is able to infect primary human cells. In this study we have analyzed endothelial cells, vascular fibroblasts, mesangial cells, mononuclear cells, hematopoetic stem cells and bone marrow stromal cells for PERV transmission. We now provide evidence for primary human endothelial cells, vascular fibroblasts, and mesangial cells to be susceptible to PERV transmission. PERV infection was productive in endothelial cells and mesangial cells. Our data confirm and extend former reports concerning the PERV infection of human cells. The PERV infection of different primary human cells represents further significant evidence for a viral risk during xenotransplantation. In this context, special attention should be directed towards productive infection of human endothelial cells: in the setting of xenotransplantation this cell type will have close contact with porcine cells and PERV particles. 相似文献
48.
Pivotal study of iodine-131-labeled chimeric tumor necrosis treatment radioimmunotherapy in patients with advanced lung cancer. 总被引:3,自引:0,他引:3
Shaoliang Chen Like Yu Changying Jiang Yan Zhao Da Sun Shenyu Li Guoqing Liao Yangchun Chen Qing Fu Qun Tao Dan Ye Peisheng Hu Leslie A Khawli Clive R Taylor Alan L Epstein Dian Wen Ju 《Journal of clinical oncology》2005,23(7):1538-1547
PURPOSE: Tumor necrosis treatment (TNT) uses degenerating tumor cells and necrotic regions of tumors as targets for radioimmunotherapy. Previous studies in animal tumor models and clinical trials have demonstrated that when linked to the therapeutic radionuclide iodine-131, recombinant chimeric TNT antibody ((131)I-chTNT) can deliver therapeutic doses to tumors regardless of the location or type of malignancy. Therapeutic efficacy and toxicity of (131)I-chTNT in advanced lung cancer patients were studied in this pivotal registration trial. PATIENTS AND METHODS: Patients with advanced lung cancer were treated with systemic or intratumoral injection of (131)I-chTNT in eight oncology centers in China. The objective response rate (ORR) was assessed as the primary end point. RESULTS: All 107 patients who were entered onto the study and completed therapy had experienced treatment failure after prior radiotherapy or chemotherapy a mean of three times. The results showed an ORR of 34.6% (complete response, 3.7%; partial response, 30.8%; no change, 55.1%; and progressive disease, 10.3%) in all patients and 33% in 97 non-small-cell lung cancer patients. A biodistribution study demonstrated excellent localization of the radioactivity in tumors in both systemically and intratumorally injected patients. The most obvious adverse side effect was mild and reversible bone marrow suppression. CONCLUSION: Radioimmunotherapy with (131)I-chTNT was well tolerated and can be used systemically or locally to treat refractory tumors of the lung. 相似文献
49.
Mitch Dowsett Steve R Ebbs J Michael Dixon Anthony Skene Clive Griffith Irene Boeddinghaus Janine Salter Simone Detre Margaret Hills Susan Ashley Stephen Francis Geraldine Walsh Ian E Smith 《Journal of clinical oncology》2005,23(11):2477-2492
PURPOSE: To investigate the relationships between biomarker changes in breast cancer during neoadjuvant (preoperative) endocrine therapy. PATIENTS AND METHODS: The IMPACT trial compared the preoperative use of tamoxifen with anastrozole alone or in combination in postmenopausal women (n = 330) with primary breast cancer. Biomarkers were measured in tumor biopsy specimens taken at baseline, and after 2 and 12 weeks of treatment. RESULTS: 52 (93%) of 56, 46 (85%) of 54, and 37 (84%) of 44 patients in the anastrozole, tamoxifen, and combination groups, respectively. There was a significantly greater suppression of Ki67 in the anastrozole-treated group than in the tamoxifen- or combination-treated groups, which is parallel to the greater efficacy seen for anastrozole over these two treatments in the Arimidex, Tamoxifen, Alone or in Combination adjuvant trial. A positive relationship was noted between estrogen-receptor level and Ki67 suppression in all patients. Ki67 was reduced to a greater extent in progesterone receptor-positive tumors compared with progesterone receptor-negative tumors. HER-2-negative tumors tended to show a greater reduction in Ki67 compared with HER-2-positive tumors, but the difference was only significant in the tamoxifen group after 2 weeks, and in the anastrozole group after 12 weeks. CONCLUSION: These results confirm the value of Ki67 as a molecular marker, and provide information regarding the relationships between treatment-induced changes in Ki67 and other important biomarkers. Studies such as this should help integrate agents targeted at growth factor signaling with endocrine agents in breast cancer. 相似文献
50.
Maria L. Napier Dash Durga Clive J. Wolsley Sarah Chamney Sharon Alexander Rosie Brennan 《Ophthalmic genetics》2015,36(3):239-243
Background: To determine the role of rhodopsin (RHO) gene mutations in patients with sector retinitis pigmentosa (RP) from Northern Ireland.Design: A case series of sector RP in a tertiary ocular genetics clinic.Participants: Four patients with sector RP were recruited from the Royal Victoria Hospital (Belfast, Northern Ireland) and Altnagelvin Hospital (Londonderry, Northern Ireland) following informed consent.Methods: The diagnosis of sector RP was based on clinical examination, International Society for Clinical Electrophysiology of Vision (ISCEV) standard electrophysiology, and visual field analysis. DNA was extracted from peripheral blood leucocytes and the coding regions and adjacent flanking intronic sequences of the RHO gene were polymerase chain reaction (PCR) amplified and cycle sequenced.Main Outcome Measure: Rhodopsin mutational status.Results: A heterozygous missense mutation in RHO (c.173C?>?T) resulting in a non-conservative substitution of threonine to methionine (p. Thr58Met) was identified in one patient and was absent from 360 control individuals. This non-conservative substitution (p.Thr58Met) replaces a highly evolutionary conserved polar hydrophilic threonine residue with a non-polar hydrophobic methionine residue at position 58 near the cytoplasmic border of helix A of RHO.Conclusions: The study identified a RHO gene mutation (p.Thr58Met) not previously reported in RP in a patient with sector RP. These findings outline the phenotypic variability associated with RHO mutations. It has been proposed that the regional effects of RHO mutations are likely to result from interplay between mutant alleles and other genetic, epigenetic and environmental factors. 相似文献