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991.
Delayed graft function (DGF) in cadaver kidney transplants is a common problem and is often due to acute tubular necrosis (ATN). DGF in transplants may have a deleterious effect on long-term graft survival. Since thyroid hormone has been shown to hasten recovery from ATN in experimental models, we designed a trial to determine if a defined course of triiodothyronine (T3) would improve the short- or long-term outcome of patients with DGF in cadaveric transplants. A prospective, randomized, placebo controlled, double blind trial of T3 was carried out in patients with DGF in cadaveric renal transplants. End-points were percentage requiring dialysis, percentage recovering function, time to recovery and length of hospital stay. Long-term outcomes were percentage grafts functioning at 1 year and mean serum creatinine at 1 year. Forty-four patients were randomized to receive either T3 or placebo. Three patients were dropped from each group when early biopsies disclosed that DGF was due to rejection. The groups were well matched by age, cold ischemia time of the graft, and percentage reactivity to a random panel of antigens. Baseline thyroid function studies, including T3, reverse T3 (rT3), and thyroid stimulating hormone (TSH) levels, were similar between the two groups and typical of 'euthyroid-sick syndrome'. T3 had no effect on percentage requiring dialysis, time to recovery, percentage recovering function, or length of stay. At 1 year follow-up, graft function was similar in both groups and significantly lower than that seen in patients with good initial function. Thyroid hormone, given early in the course of DGF in cadaver kidney recipients, had no effect on the course of DGF. Long-term graft function is impaired in patients who experience post-transplant DGF compared to those who have good initial function.  相似文献   
992.
The optimal allocation of cadaveric kidneys for transplantation with reference to human leukocyte antigen (HLA) match and sharing these organs to a distant center remains controversial. The current analysis was performed using the United Network for Organ Sharing (UNOS) database for cadaveric kidney transplants (Tx) between 1988 and 1997. The graft survivals of zero-mismatch (matched) kidneys with the mate (mismatched) kidneys were compared. There were 2385 donors and 4770 Tx. Significant differences in recipient demographics between matched and mismatched Tx were: fewer African-American race (AA) in the matched group (9.0% vs. 21.9%), higher number of previous Tx (25.5% vs. 14.8%) and elevated mean cold ischemia time (24.0 vs. 22.2 h). Post-Tx dialysis requirements were similar (22.8% vs. 24.1%, p = 0.62) and matched kidneys had to travel more distance (920 vs. 232 miles). Using a Cox model, the matched group had a decreased relative hazard of graft failure of 23.0% (p = 0.0002) or 35% (p < 0.0001) with and without censoring for death. There was significantly better graft survival in the matched recipients in all pairs except AA (matched) and non-AA (mismatched). For older donors (> or = 50 years, n = 1508), the matched grafts survival was marginally significant (p =0.05). Matched kidneys have improved survival compared with the mismatched kidneys despite the longer distance traveled. The benefit of mismatched transplants was predominantly seen in non-AA.  相似文献   
993.
BACKGROUND: This meta-analysis was performed to determine the degree to which improvements in open hernia repair (OHR) in the last decade have altered the relative benefit of laparoscopic hernia repair (LHR). METHODS: Twenty-seven comparative trials including 4,688 randomized patients were evaluated. RESULTS: Within the control OHR, patients with routine mesh repair returned to work earlier than a sutured repair (16.4 versus 27.3 days, P = 0.010). During the study period, the increased use of mesh in OHR (3 of 12 initially versus 9 of 15 subsequent studies) was associated with an earlier return to work (25.9 to 16.8 days, P = 0.017); there was no significant improvement with corresponding LHR. CONCLUSIONS: Although LHR was associated with an earlier return to work compared with conventional sutured OHR, more recent mesh OHRs provide equivalent outcomes but at lower costs and potentially less severe complications, supporting an open technique using preperitoneal mesh prostheses as the optimal hernia repair.  相似文献   
994.
We examined the effects of early blockade of CD62 selectin-mediated adhesive interactions in steatotic rat liver models of ex vivo cold ischemia followed by reperfusion or transplantation by administration of P-selectin glycoprotein ligand-1 (rPSGL-Ig). In the model of cold ischemia/reperfusion, livers pretreated ex vivo with rPSGL-Ig at harvesting from obese Zucker rats showed significantly decreased portal resistance, increased bile production, and diminished hepatic endothelial neutrophil infiltration, as compared with untreated controls. Pretreatment of fatty livers with rPSGL-Ig prior to transplantation extended the survival of lean Zucker rat recipients from 40% to 90%. This effect correlated with significantly improved liver function, depressed neutrophil activity, and decreased histologic features of hepatocyte injury. Intragraft expression of CD62 P-selectin was similar in both recipient groups. rPSGL-Ig treatment decreased intragraft infiltration by CD3/CD25 cells, diminished expression of pro-inflammatory TNFalpha, IL-6, iNOS, IL-2 and IFN-gamma, without significantly affecting mRNA levels coding for anti-inflammatory IL-4. Thus, rPSGL-Ig blockade of CD62-mediated adhesive interactions protects against severe ischemia/reperfusion injury suffered otherwise by steatotic rat livers. These findings document the potential utility of rPSGL-Ig in increasing the transplant donor pool through modulation of marginal steatotic livers.  相似文献   
995.
BACKGROUND: The development of de novo diabetes mellitus is a serious complication of kidney transplantation. This study examined the cardiovascular risk profile of patients with post-transplant diabetes (PTDM) and assessed the impact of PTDM on patient survival. METHODS: This analysis included 1811 adult, renal allograft recipients, transplanted in a single institution between 1983 and 1998. Patient survival was analyzed by univariable and multivariable Cox regression considering PTDM as a time dependent variable. RESULTS: After a follow-up period of 8.3 +/- 4.5 years, 293 patients (20%) developed PTDM, 14% lost their graft, and 20% died. Compared to patients without DM (NoDM, N = 1186) patients with PTDM were significantly older (40 +/- 14 vs. 48 +/- 12 years, P < 0.001), heavier (76 +/- 23 vs. 86 +/- 25 kg, P < 0.001), and included more African Americans (18 vs. 28%, P = 0.001). In addition, the incidence of PTDM was significantly higher in patients who were transplanted after 1995 than prior to that year. In contrast, there were no significant differences between PTDM and patients who had DM before the transplant (DM; N = 332). Compared to NoDM, patients with PTDM had significantly higher total serum cholesterol and triglycerides (TG), higher systolic blood pressure and higher pulse pressure throughout the post-transplant period. Of interest, all of these abnormalities preceded the development of PTDM. Hypertriglyceridemia was particularly pronounced in PTDM and elevated TG levels correlated with the subsequent development of PTDM, independent of other risk factors (P = 0.001 by multivariate Cox). Compared to NoDM (16% mortality) a significantly higher percent of DM (31%, P < 0.001) and PTDM (22%, P = 0.005) patients died. By Cox regression, PTDM correlated with reduced patient survival (hazard ratio = 1.80, CI 1.35 to 2.41, P = 0.001), and that relationship was independent of other correlates of reduced survival that included: increasing age; transplant year; reduced serum albumin; and male sex. CONCLUSION: s: PTDM is associated with an unfavorable cardiovascular risk profile that precedes the development of hyperglycemia. PTDM is an independent predictor of reduced survival in renal allograft recipients.  相似文献   
996.
BACKGROUND: Central venous catheters are frequently needed for the provision of haemodialysis, but their clinical usefulness is severely limited by infectious complications. The risk of such infections can be reduced by topical application of mupirocin to the exit sites of non-cuffed catheters or by the use of tunnelled, cuffed catheters. Whether mupirocin offers any additional protection against infection in patients with tunnelled, cuffed haemodialysis catheters has not been studied. METHODS: An open-label, randomized controlled trial was performed comparing the effect of thrice-weekly exit site application of mupirocin (mupirocin group) vs no ointment (control group) on infection rates and catheter survival in patients receiving haemodialysis via a newly inserted, tunnelled, cuffed central venous catheter. All patients were followed until catheter removal and were monitored for the development of exit site infections and catheter-associated bacteraemias. RESULTS: Fifty patients were enrolled in the study. Both the mupirocin (n=27) and control (n=23) groups were similar at baseline with respect to demographic characteristics, comorbid illnesses and causes of renal failure. Compared with controls, mupirocin-treated patients experienced significantly fewer catheter-related bacteraemias (7 vs 35%, P<0.01) and a longer time to first bacteraemia (log rank score 8.68, P<0.01). The beneficial effect of mupirocin was entirely attributable to a reduction in staphylococcal infection (log rank 10.69, P=0.001) and was still observed when only patients without prior nasal Staphylococcus aureus carriage were included in the analysis (log rank score 6.33, P=0.01). Median catheter survival was also significantly longer in the mupirocin group (108 vs 31 days, log rank score 5.9, P<0.05). Mupirocin use was not associated with any adverse patient effects or the induction of antimicrobial resistance. CONCLUSIONS: Thrice-weekly application of mupirocin to tunnelled, cuffed haemodialysis catheter exit sites is associated with a marked reduction in line-related sepsis and a prolongation of catheter survival.  相似文献   
997.
OBJECT: The intracellular events transducing mitogenic signals from platelet-derived growth factor-beta (PDGFbeta) receptor tyrosine kinases are not precisely known. In this study the authors evaluated whether the phosphatidylinositol 3-kinase (PI3-K)-Akt-p70S6K pathway is expressed in meningiomas, regulates their growth, and transduces mitogenic signals of PDGF-BB. METHODS: Nine meningioma tumors obtained in humans were evaluated using Western blot analysis for phosphorylated (activated) Akt and phosphorylated p70S6K. Cells cultured from seven of these meningiomas were also screened using Western blot analysis for Akt and for phosphorylated Akt and p70S6K. The authors also evaluated whether PDGF-BB stimulation of meningioma cells was associated with the phosphorylation of Akt and p70S6K known to activate these kinases. In addition, the effects of wortmannin, an inhibitor of P13-K, on proliferation and activation of Akt and p70S6K in meningioma cells stimulated with PDGF-BB were evaluated. Western blots of lysates from meningiomas demonstrated phosphorylated Akt and p70S6K. Treatment with PDGF-BB stimulated phosphorylation of Akt and p70S6K in each meningioma cell culture. Wortmannin (500 and 1000 nM) significantly decreased PDGF-BB stimulation of meningioma cells (p < 0.001) while it reduced Akt and p70S6K phosphorylation but not mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) phosphorylation. CONCLUSIONS: These findings indicate that Akt and p70S6K are constitutively expressed and activated in meningioma cells and that the PI3-K-Akt-p70S6K pathway may participate in transduction of mitogenic signals in meningiomas independent of the Raf-1-MEK-1-MAPK/ERK cascade.  相似文献   
998.
HYPOTHESIS: We hypothesized that selected septuagenarians may do as well after transplantation as those of a younger group of older recipients. This work compares post-liver transplant survival in septuagenarians with that of patients aged 50 to 59 years. DESIGN: Review of a prospectively maintained database. SETTING: University transplant center. PATIENTS: First-time liver transplant recipients treated from January 1, 1988, to December 31, 2005. Group 1 consisted of liver transplant recipients aged 70 years or older at the time of transplant. Group 2 was a younger cohort of patients aged 50 to 59 years. INTERVENTIONS: Liver transplantation. MAIN OUTCOME MEASURES: Patient survival. Survival data were stratified, Kaplan-Meier survival was calculated, and a multivariate analysis was performed. RESULTS: Group 1 included 62 patients aged 70 years or older (average, 71.9 +/- 2.1 years). Group 2 included 864 patients aged 50 to 59 years (average, 54.3 +/- 2.9 years). Unadjusted patient survival of group 1 at 1, 3, 5, and 10 years was 73.3%, 65.8%, 47.1%, and 39.7%, respectively. Unadjusted patient survival of group 2 at 1, 3, 5, and 10 years was 79.4%, 71.5%, 65.3%, and 45.2%, respectively. The difference was not statistically significant (P = .14). Multivariate analysis for factors affecting survival demonstrated preoperative hospitalization, cold ischemia time, and hepatitis C/ethanol as risk factors for death. Age 70 years or more was not a strong risk factor (mortality ratio, 1.28; P = .27). CONCLUSIONS: When other risk factors for mortality are controlled in older recipients, risk of death due to age is reduced in well-selected recipients. Age by itself should not be used to limit liver transplantation.  相似文献   
999.
Dislocation of the proximal tibiofibular joint (PTFJ) in association with a displaced tibial shaft fracture and an intact fibula is an exceedingly rare injury. We present 2 cases of tibia fractures associated with an intact fibula and a PTFJ dislocation. The first case involves a man who sustained a closed spiral fracture of the distal tibial shaft, with an intact fibula, an anterolaterally dislocated PTFJ, and a partial tear of the lateral collateral ligament. The tibia was percutaneously plated, and the PTFJ was reduced and then stabilized with temporary screw fixation. The second case involves a woman who sustained a closed fracture of the tibia in association with a PTFJ dislocation. The tibia was fixed with an intramedullary nail, and the PTFJ was similarly reduced and fixed with a temporary screw. We also provide a brief literature review focusing on classification of PTFJ dislocations, mechanism of injury, associated injuries, and treatment options.  相似文献   
1000.
Investigation of the bypassed stomach in patients with suspected peptic ulcer disease presents a major challenge to bariatric surgeons. Various methods have been suggested for visualization of the duodenum and bypassed stomach. These include endoscopy via percutaneous gastrostomy access, retrograde endoscopy and virtual gastroscopy using CT scan. We present a case of peptic ulcer bleeding diagnosed with the help of conventional CT scan. To the best of our knowledge, this is the second such case reported in the literature and the first in the bariatric population.  相似文献   
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