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PurposeTo define how much of renal function was determined by the preserved renal parenchymal volume and the ischemic insult during partial nephrectomy (PN) long after surgery.MethodsWe analyzed the data of 530 consecutive patients who had undergone PN. For all patients, renal function was measured preoperatively and again at 3 postoperative months, then annually using 99mTc-diethylenetriaminepentaacetic acid renal scan. Perioperative variables potentially affecting the long-term ipsilateral glomerular filtration rate (GFR) and their time-varying contribution were assessed using a linear mixed model.ResultsThe mean preoperative ipsilateral GFR was 42.9 ml/min, which decreased by 27.3% at 3 months but began to recover thereafter continuing until 4 years (Δ% GFR at 1, 2, 3, 4, and 5 years: 22.3%, 18.5%, 14.7%, 10.0%, and 9.6%, respectively). Parenchymal volume reduction and ischemic time were significantly associated with postoperative ipsilateral GFR throughout observation period unvarying with time. Diabetes and proteinuria were not significant determinants of ipsilateral function at 3 months but became significant at 5 years. In multivariate analysis regarding recovery slope, volume reduction (β = ?0.026, SE 0.006, P < 0.0001), preoperative ipsilateral GFR (β = ?0.021, SE 0.007, P = 0.0012), proteinuria (β = ?0.942, SE 0.372, P = 0.0116), and diabetes (β = ?0.396, SE 0.197, P = 0.0447) were independently significant.ConclusionIpsilateral renal function continued to improve until 5 years after PN. Parenchymal volume loss was the major determinant and its impact on long-term ipsilateral renal function remained constant while ischemic time affected early GFR reduction with its impact diminishing over time. Patient-related factors including diabetes and proteinuria gained significance over time and became independent determinants of recovery slope.  相似文献   
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BackgroundThere is an increasing demand for prognostic immune biomarkers of cancer. The prognostic significance of immune markers has been shown for various cancers, but biomarkers of bladder cancer (BCa) have not been fully evaluated. To clarify the role of human leukocyte antigen DR alpha chain (HLA-DRA) in BCa development, we examined expression of HLA-DRA mRNA in tissue samples of non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC).Materials and MethodsTissues of 96 NMIBC, 43 MIBC and 59 controls comprising noncancerous BCa surrounding tissues were used to examine the expression of HLA-DRA gene by real-time polymerase chain reaction. The expression of up-stream genes regulating HLA-DRA were also measured to explain the role of HLA-DRA in BCa.ResultsPatients with high grade NMIBC showed higher expression of HLA-DRA than those with low grade NMIBC (P < 0.05). In addition, NMIBC patients who progressed to MIBC showed high expression of HLA-DRA mRNA. Kaplan-Meier analysis showed that NMIBC patients with low expression of HLA-DRA had better progression-free survival than those with high expression (P = 0.004). Moreover, the expression of genes regulating HLA-DRA varied in NMIBC and MIBC, indicating a different immunoregulation effect of HLA-DRA in both cancers.ConclusionsHigh expression of HLA-DRA in NMIBC patients has implications for patient stratification strategies, as well as for BCa tumor immunology.  相似文献   
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Introduction: Computed tomography (CT) can be used to assess bone status with measurement of Hounsfield unit (HU). The objective of this study was to evaluate whether HU of muscle might be associated with parameters of bone and muscle status. Methods: We reviewed 71 women aged over 50 yr of age who had distal radius fracture and underwent CT evaluation of affected wrist. We assessed HUs of forearm flexor muscles (flexor digitorum superficialis) and thenar muscles and bone HUs at the capitate and the ulnar head. Other parameters included femur neck and lumbar bone mineral density (BMD), upper extremity lean mass, hand grip strength, and muscle fiber cross-sectional area. We performed correlation analyses to determine associations between variables. Results: Thenar and forearm muscle HUs were significantly correlated with each other, but not with other parameters. HUs of the capitate and ulnar head were positively correlated with femur neck and lumbar BMDs and inversely correlated with age. Ulnar head HU was positively correlated hand grip strength. Conclusions: HUs of forearm and thenar muscles did not show significant correlations with bone or muscle parameters, although bone HUs correlated well with bone mineral densities. These results support the opportunistic use of CT for evaluating bone fragility. Clinical usefulness of muscle HU measurement needs further studies.  相似文献   
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BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.  相似文献   
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Medical devices may revolutionize healthcare delivery but can lead to serious adverse events for treated patients and users. While reporting of adverse events related to medical devices is an essential starting point for post-market surveillance, underreporting of medical device adverse events is a global problem. Korea introduced a voluntary medical device adverse event reporting system in 2010, called the Medical Device Safety Information Monitoring Center, which has led to an increase in adverse event reports. For 10 years, the Medical Device Safety Information Monitoring Center has analyzed medical device adverse events systematically and has provided active feedback to the manufacturers and education on safe use. Recently, the Medical Device Safety Information Monitoring Center contributed to harmonization of international medical device vigilance through the sharing of adverse events. This experience of Korea might contribute to improvements in medical device vigilance, which is a critical prerequisite for improving medical device policies and regulations.  相似文献   
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An efficient synthesis of 3-(E)-hydroxy- and 3-(E)-acetoxypropenylcephem derivatives, key intermediates for the synthesis of 3-(E)-propenylcephalosporins was achievedvia Stille coupling reaction of 3-trifloxycephem with 3-(E)-tributylstannylallylic alcohol.  相似文献   
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