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Rats fed a basal, low-selenium diet, or this diet supplemented with 0.1 ppm and 1.0 ppm selenium and treated with cadmium, showed significant reductions in the activity of the selenoenzyme glutathione peroxidase in kidney and liver. Cadmium treatment resulted in a significant increase in the activity of selenium-independent glutathione peroxidase activity in the liver of selenium-supplemented rats. Selenium-independent glutathion peroxidase activity was significantly reduced in the kidney of rats fed the basal low-selenium diet. There was no significant increase in lipid peroxidation in any of the groups studied. Cadmium concentrations in the kidney and liver of these animals ranged from about 250 to 700 g Cd/g tissue, dry weight.Supported by NIEHS Center Grant ES-00159 and a Grant from the Selenium-Tellurium Development Association 相似文献
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A case is presented of an eight-year-old child with a mediastinal tumour, who had developed acute renal failure following the institution of steroid therapy. Intrapleural analgesia was successfully used for the insertion of a peritoneal dialysis catheter so that the considerable risks of general anaesthesia were avoided. Subsequent dialysis allowed chemotherapy to commence and, as a result of the shrinkage in tumour size, general anaesthesia was administered safely two days later. The purpose of this report is to highlight the use of intrapleural analgesia in children as an alternative to general anaesthesia, when the latter is contraindicated. The mechanism of action of intra-pleural analgesia and the risks of anaesthesia in the presence of a mediastinal tumour are discussed. 相似文献
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OBJECTIVE: To develop and validate a short form version of the Endometriosis Health Profile-30 questionnaire which consists of a 30-item core questionnaire and a 23 item modular questionnaire. METHODS: Three studies were carried out to develop the Endometriosis Health Profile-5. Study 1: a short form version of the Endometriosis Health Profile-30 core questionnaire was developed. Study 2: the results were verified in a new data set. Study 3: a short form version of the 23 item modular questionnaire was produced. The modular questionnaire contains six dimensions which may not be applicable to every woman with endometriosis and is used to supplement the five scales on the core questionnaire when required. RESULTS: The final instrument contained 11 items: five items from the core questionnaire and six items from the modular questionnaire. The 95% confidence intervals for Study 1 indicated that the scale scores overlapped with each item score and were confirmed in the second analysis (study 2). Each item was most highly correlated to its parent scale and less with the remaining four core questionnaire scales which was verified in study 2. In both studies all correlations were significant at the 0.01 level (two tailed test). CONCLUSION: The Endometriosis Health Profile-5 is a reliable and valid short form questionnaire which can also be supplemented with a short form version of the modular questionnaire when required. It will be especially useful in clinical settings where a short and economical endometriosis health status measure is required. 相似文献
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Guy N.J. Betts Amanda Eustace Shalini Patiar Helen R. Valentine Joely Irlam Anassuya Ramachandran Ashirwad Merve Jarrod J. Homer Carla Möller-Levet Francesca M. Buffa Gillian Hall Crispin J. Miller Adrian L. Harris Catharine M.L. West 《European journal of cancer (Oxford, England : 1990)》2013,49(1):156-165
Background and purposeTumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours.Materials and methodsTumour samples (n = 201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV).ResultsThe assay was sensitive with linear reaction efficiencies across a 4log10 range of inputted cDNA (0.001–10 ng/μl). Intra- (CoV = 6.9%) and inter- (CoV = 2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO2. TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p < 0.01) and positive pimonidazole scores (p = 0.005).ConclusionsGene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material. 相似文献
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Mei L. Tan Peng Shao Anna M. Friedhuber Mallory van Moorst Mina Elahy Sivanjah Indumathy Dave E. Dunstan Yongzhong Wei Crispin R. Dass 《Biomaterials》2014
Bone defects caused by fractures or cancer-mediated destruction are debilitating. Chitosan is commonly used in scaffold matrices for bone healing, but rarely as a free drug. We demonstrate that free chitosan promotes osteoblast proliferation and osteogenesis in mesenchymal stem cells, increases osteopontin and collagen I expression, and reduces osteoclastogenesis. Chitosan inhibits invasion of endothelial cells, downregulating uPA/R, MT1-MMP, cdc42 and Rac1. Better healing of bone fractures with greater trabecular bone formation was observed in mice treated with chitosan. Chitosan induces apoptosis in osteotropic prostate and breast cancer cells via caspase-2 and -3 activation, and reduces their establishment in bone. Chitosan is pro-apoptotic in osteosarcoma cells, but not their normal counterpart, osteoblasts, or chondrosarcoma cells. Systemic delivery of chitosan does not perturb angiogenesis, bone volume or instinctive behaviour in pregnant mice, but decreases foetal length and changes pancreatic secretory acini. With certain controls in place, chitosan could be useful for bone trauma management. 相似文献
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Xiaohui Yu Lifang Yang Murray J. Cairns Crispin Dass Edward Saravolac Xiong Li Lun-Quan Sun 《Oncotarget》2014,5(19):9039-9048
DNAzymes are a novel class of gene suppressors that selectively bind to an RNA substrate by Watson-Crick base pairing and cleave phosphodiester bonds. To explore the potential for therapeutic use of catalytic DNA molecules, active DNAzymes targeting the bcl-xL gene were generated through a multiplex in vitro selection. The DNAzyme-mediated down-regulation of the bcl-xL expression was demonstrated in various cancer cell lines by Western blots. Treatment of the cells with the active DNAzyme led to increases in percentage of apoptotic cells and cytochrome c release from mitochondria, a hall marker of apoptosis. When combined with chemotherapeutics such as Taxol, the DNAzyme significantly sensitised a panel of cancer cells to apoptosis as measured by cell survival assay. In Taxol-resistant cells, down-regulation of bcl-xL expression by the DNAzyme reversed the chemo-resistant phenotype of the cancer cells. In a xenograft mouse model, the DNAzyme was delivered into the tumors via an ALZET osmotic pump and shown to chemosensitize PC3 tumor when treating with Taxol. The results from the present study demonstrate that bcl-xL DNAzyme treatment facilitates apoptosis in solid tumors and suggest the potential use of bcl-xL DNAzyme in combination with chemotherapeutics for cancer therapy. 相似文献