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Thiazolidinediones (TZDs), agonists of the nuclear receptor peroxisome proliferator-activated receptor-γ, induce the expression of many genes, including several enzymes and transporters involved in glucose and lipid metabolism. Although the efficacy of TZDs on blood glucose control in type 2 diabetes is not questionable, their cardiovascular effects have been debated, with beneficial or harmful actions suggested by different authors. This article reviews the available clinical evidence on the cardiovascular effects of TZDs, discussing possible mechanisms underlying the observed effects and suggesting some directions for future research.  相似文献   
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CONTEXT: Increasing evidences from experimental and human studies suggest that the activity of the growth hormone (GH/insulin-like growth factor-I) axis may contribute to the age-related cognitive decline and poor cognition in late life. OBJECTIVE: The aim of the present study was to evaluate the relationship of total serum free IGF-I and its binding protein-3 with cognitive performance in older persons aged 80 years or older. DESIGN: Data are from baseline evaluation of the ilSIRENTE study (n=353). Cognitive performance was evaluated using five items enclosed in the Minimum Data Set for Home Care assessment form: short-term memory, procedural memory, cognitive skills in daily decision making, verbal expression, comprehension. Free insulin-like growth factor-I (free IGF-I) and IGF-binding protein-3 (IGFBP-3) in blood were measured. Analysis of covariance (ANCOVA) was used to examine the relationship between cognitive impairment and the serum free IGF-I and IGFBP-3 concentrations, after adjustment for potential confounding variables. RESULTS: After adjustment for potential confounders, which included age, gender, education, cerebrovascular disease, ischemic heart disease, congestive heart failure, hypertension, diabetes, depression, Parkinson diseases, thyroid diseases, smoking status, alcohol abuse, body mass index, and number of medications, individuals with verbal expression problems (n=20) and individuals with comprehension problems (n=24) had a significantly lower serum levels of readily dissociable IGF-I than participants without cognitive impairments. The serum IGFBP-3 presented the same behavior of free IGF-I. CONCLUSION: The present study suggests that among old-old subjects living in the community lower levels of total serum free IGF-I and IGFBP-3 are associated with impairment of cognitive performance. This finding suggests that the GH/IGF-I axis may play an important role in the age-related decline of cognitive performance.  相似文献   
4.
Endovascular repair for concomitant multilevel aortic disease.   总被引:2,自引:0,他引:2  
OBJECTIVE: Patients with multilevel aortic disease represent a small subgroup with the need for extensive surgical treatment at considerable risk. We present our experience of endovascular exclusion for simultaneous thoracic and abdominal aortic disease in four patients. METHODS: Between January 2002 and January 2005, four patients underwent endovascular repair for simultaneous thoracic and abdominal aortic disease. Mean age was 69+/-10 years (range, 60-81). Thoracic lesions included penetrating aortic ulcer (n=2, ruptured=1), atherosclerotic aneurysm (n=1), and chronic type B dissection (n=1). Abdominal aortic disease included atherosclerotic infrarenal (n=3) and juxtarenal (n=1) aortic aneurysms. Thoracic aortic stent-grafts had been the following: Excluder/TAG (n=3) or Talent (n=1) straight tube devices. Abdominal aortic stent-grafts used were as following: Excluder (n=3) or Zenith (n=1). All patients were followed-up with CT-angiography and chest X-rays 1, 4, 12 months after the procedure, and once per year thereafter. RESULTS: Stent-graft deployment was technically successful in all cases. Intraoperative mortality was not observed. Mean procedure time was 94+/-34 min (range, 70-145). Early postoperative complications occurred in one patient that developed acute renal failure but dialysis was not required. Mean hospitalisation was 8+/-5 days (range, 4-15). Late death occurred in one patient for an undetected ruptured thoracic type 1 endoleak. All three survivors are currently well 16.5 months (range, 3-36) after surgery. No neurological complications developed. CONCLUSION: Simultaneous abdominal and thoracic endovascular repair for multilevel aortic disease is feasible and could be a viable alternative in high-risk patients, who otherwise may not be suitable candidates for conventional repair.  相似文献   
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S100A1 is a calcium-binding protein, which has been recently found in renal cell neoplasms. We evaluated the diagnostic utility of immunohistochemical detection of S100A1 in 164 renal cell neoplasms. Forty-one clear cell, 32 papillary, and 51 chromophobe renal cell carcinomas, and 40 oncocytomas, 164 samples of normal renal parenchyma adjacent to the tumors and 13 fetal kidneys were analyzed. The levels of S100A1 mRNA detected by quantitative RT-PCR analysis of frozen tissues from seven clear cell, five papillary, and six chromophobe renal cell carcinomas, four oncocytomas, and nine samples of normal renal tissues adjacent to neoplasms were compared with the immunohistochemical detection of protein expression. Clear cell and papillary renal cell carcinomas showed positive reactions for S100A1 in 30 out of 41 tumors (73%) and in 30 out of 32 (94%) tumors, respectively. Thirty-seven renal oncocytomas out of 40 (93%) were positive for S100A1, whereas 48 of 51 (94%) chromophobe renal cell carcinomas were negative. S100A1 protein was detected in all samples of unaffected and fetal kidneys. S100A1 mRNA was detected by RT-PCR in all normal kidneys and renal cell neoplasms, although at very different levels. Statistical analyses comparing the different expression of S100A1 in clear cell and chromophobe renal cell carcinomas observed by immunohistochemical and RT-PCR methods showed significant values (P<0.001), such as when comparing by both techniques the different levels of S100A1 expression in chromophobe renal cell carcinomas and oncocytomas (P<0.001). Our study shows that S100A1 protein is expressed in oncocytomas, clear cell and papillary renal cell carcinomas but not in chromophobe renal cell carcinomas. Its immunodetection is potentially useful for the differential diagnosis between chromophobe renal cell carcinoma and oncocytoma. Further, S100A1 protein expression is constantly detected in the normal parenchyma of the adult and fetal kidney.  相似文献   
8.
A number of substituted 2-[(2,2,2-trifluoroethyl)sulfonyl]-1H-benzimidazoles (4) have demonstrated antiinflammatory activity that appears to have a mechanism distinct from typical cyclooxygenase inhibiting nonsteroidal antiinflammatory drugs. Several of these compounds inhibit adjuvant-induced arthritis in rats at 25 mg/kg while showing no activity in the carrageenan paw edema model at up to 100 mg/kg. Two compounds, 4a and 4b, showed no significant inhibition of cyclooxygenase in vitro at concentrations as high as 5 X 10(-5) M. All compounds 4 active in adjuvant-induced arthritis were also found to inhibit release of lysosomal enzymes from neutrophils, raising the possibility that their antiinflammatory effect is at least partially mediated by an effect on neutrophil function.  相似文献   
9.
Functional decline in frail community-dwelling stroke patients   总被引:1,自引:0,他引:1  
Patients who suffer a stroke event are at high risk of functional decline after the post-acute rehabilitation period. The aim of the present study was the evaluation of factors associated with functional decline in a large sample of older patients with stroke living in the community. The study population consisted of all patients admitted to home care programs after a post-acute rehabilitation program--with at least 1 year of follow-up--in twenty-two Italian Home Health Agencies from 2000 to 2002 (n=1338). For the present study we selected 355 (26%) patients with diagnosis of stroke. After 1 year of in-home care program, 149 out of 355 stroke survivors (42%) had presented a worsening in the activities of daily living (ADL) scale score. In the final adjusted model, patients with cognitive impairment (OR 2.59, 95% CI, 1.45-4.64), pressure ulcer (OR 2.74, 95% CI, 1.45-5.18), urinary incontinence (OR 1.64, 95% CI, 1.01-3.29), or hearing impairment (OR 1.83, 95% CI, 1.02-3.29) were more likely to significantly decline in physical functioning after a period of 1 year in-home care program. Our study documents that functional decline of stroke patients was largely dependent on specific subjects' clinical characteristics. Three of four concomitant disabling conditions associated in our sample with functional decline--pressure ulcer, urinary incontinence, hearing--can be prevented and eventually treated or modified. Appropriate post-acute rehabilitation programs and adequate home care interventions focused on the prevention and treatment of these conditions might be correlated to better outcomes in older post-stroke patients.  相似文献   
10.
It has been suggested that gains of chromosomes 7 and 17 and loss of Y occur in renal papillary adenoma and that progression to papillary renal cell carcinoma is marked by gains of additional chromosomes, most frequently 12, 16, and 20. Previous studies have included very few lesions of <5 mm in diameter, a requirement of the present definition of papillary adenoma. Ten papillary adenomas (ranging from 1 to 5 mm in diameter) from autopsy material and 10 surgically resected papillary renal cell carcinomas were studied with fluorescence in situ hybridization in paraffin sections using centromeric probes for chromosomes 7, 12, 16, 17, 20, and Y diluted 1:100 with tDenHyb1 buffer. The signals in 50 to 150 nuclei were counted in each tumor. Controls for all the probes were normal renal tissues from the same patients. Three or more signals per nucleus were frequently observed in papillary adenomas: chromosome 7 (range, 10 to 50%; > or = 30% in 9 of 10), 17 (range, 10 to 47%; > or = 30% in 7), 16 (range, 1 to 63%; > or = 10% in 5), 12 (range, 0 to 32%; > or =10% in 4), and 20 (range, 5 to 49%; > or = 10% in 5). Loss of the Y chromosome was observed in 80 to 90% of nuclei in 9 adenomas from males. Three or more signals were frequent in papillary renal cell carcinomas: chromosome 7 (range, 32 to 63%; > or =30% in 10 of 10), 17 (range, 28 to 61%; > or = 30% in 7), 16 (range, 0 to 45%; > or = 10% in 6), 12 (range, 1 to 37, > or = 10% in 5), 20 (range, 2 to 44%; > or = 10% in 4). No signal for Y was observed in 12 to 88% (> or = 81% in 6) of nuclei in 7 carcinomas from males. Statistical analysis showed no difference between adenomas and carcinomas. Gains of chromosomes 7, 17, 16, 12, and 20 and loss of the Y chromosome occur early in the evolution of papillary renal cell neoplasia in tumors that are only a few millimeters in diameter. Progressive gains of these chromosomes do not appear to correlate with the transition from adenoma to carcinoma.  相似文献   
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