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71.
To define the effects of acute hyperglycemia per se (i.e., without the confounding effect of hyperinsulinemia) in human tissues in vivo, we performed global gene expression analysis using microarrays in vastus lateralis muscle and subcutaneous abdominal adipose tissue of seven healthy men during a hyperglycemic-euinsulinemic clamp with infusion of somatostatin to inhibit endogenous insulin release. We found that doubling fasting blood glucose values while maintaining plasma insulin in the fasting range modifies the expression of 316 genes in skeletal muscle and 336 genes in adipose tissue. More than 80% of them were downregulated during the clamp, indicating a drastic effect of acute high glucose, in the absence of insulin, on mRNA levels in human fat and muscle tissues. Almost all the biological pathways were affected, suggesting a generalized effect of hyperglycemia. The induction of genes from the metallothionein family, related to detoxification and free radical scavenging, indicated that hyperglycemia-induced oxidative stress could be involved in the observed modifications. Because the duration and the concentration of the experimental hyperglycemia were close to what is observed during a postprandial glucose excursion in diabetic patients, these data suggest that modifications of gene expression could be an additional effect of glucose toxicity in vivo.  相似文献   
72.
BACKGROUND: The influence of the preservation solution used for in situ perfusion of the donor and pancreas storage on islet isolation has received little attention. METHODS: In this prospective controlled trial, we compared the outcome of human islet isolation from pancreata perfused with University of Wisconsin (UW) solution or Celsior, an alternative colloid-free extracellular solution. RESULTS: At the 1-year interim analysis, the viability and insulin secretion of islets isolated from donors perfused with UW (n=19) or Celsior (n=5) were identical. However, total islet recovery (IEQ) and isolation yield (IEQ/g) were 1.8-fold and 2.1-fold inferior in the Celsior group (P<0.05 vs. UW). Overall, 13 (68%) of islet preparations were effectively transplanted from the UW group vs. none from the Celsior group (P=0.01). The clinical study was discontinued and the causes of these differences were further explored in the pig (n=14). In contrast to UW, Celsior induced cell swelling and pancreas edema after only four hours of cold storage. These abnormalities were delayed when the donor was perfused with Solution de Conservation d'Organes et de Tissus (SCOT), an extracellular solution containing polyethylene glycol. CONCLUSIONS: Our results suggest that colloid-free preservation solutions might be suboptimal for pancreas perfusion and cold storage prior to islet isolation and transplantation. Because pancreata are now frequently recovered for islet transplantation, preliminary experimental and clinical data about islet isolation should be obtained prior to the routine implementation of new preservation solutions for abdominal perfusion during multiorgan recovery.  相似文献   
73.
BACKGROUND: An imbalance in the ratio of arachidonic acid and docosahexaenoic acid (DHA) was found in cystic fibrosis (CF) affected tissues and was suggested to promote inflammation. Several studies have shown that the long chain n-3 fatty acids reduced inflammatory activity while others have highlighted prooxidant activity of DHA at high concentrations. The aim of our study was to evaluate the effects of an intravenous fish-oil emulsion enriched with n-3 FA in patients with CF on plasma and platelet FA composition and peroxidation markers. METHODS: 13 patients with CF received one IV emulsion per week of 2 mL/kg fish-oil n-3 emulsion for 12 weeks. RESULTS: There was a significant increase in 20:5 n-3 and 22:6 n-3 platelet FA composition, no variation in 20:4 n-6, a decrease in n-9. There was no variation in plasma FA composition. Specific urinary markers of lipid peroxidation derived from n-3 and n-6 showed a very high level before infusion compared with usual values in healthy subjects which was not affected by treatment. A significant weight loss and a decrease in reduced glutathione were observed in adult patients. CONCLUSIONS: The intravenous administration of n-3 FA in CF patients induced a significant modification in platelet FA composition but no modification of oxidative markers. However, the weight loss and the decreased level in reduced glutathione observed in adult patients may suggest a potential deleterious activity for some patients. Further studies are necessary to determine the optimal dose and route for long chain FA administration required to reach a potential beneficial effect.  相似文献   
74.
Tumor thrombus in major vasculature is a frequent finding with a poor long-term prognosis in patients with hepatocellular carcinoma (HCC). The utility of surgical resection is still controversial. This study compared morbidity and survival after resection for HCC with and without tumor thrombus. Data of 108 patients who underwent major hepatic resection for HCC were prospectively recorded. Patients were divided into two groups. The venous thrombectomy (VT) group included 26 patients who had HCC with tumor thrombus in the portal or hepatic veins. The matched control group included 82 patients who had HCC without tumor thrombus. Surgical technique, early outcome, and late survival were analyzed in each group. Multivariate analysis was performed to assess the prognostic value of this feature. Surgical technique was comparable in the VT and control group with regard to extent of hepatectomy, procedure duration, and transfusion requirements. Early postoperative outcome was also comparable. Actuarial survival at 1, 3, and 5 years was 38%, 20%, and 13%, respectively, in the VT group (median: 9 months) versus 74%, 56%, and 33%, respectively, in the control group (median: 41 months). In the subgroup of patients with tumor thrombus limited to the portal vein, actuarial survival at 1, 3, and 5 years was 50%, 26%, and 17%, respectively, (median: 12 months) and two patients lived longer than 5 years. Multivariate analysis showed that incomplete resection, alphafetoprotein level greater than 100 N, more than two tumor nodules, and tumor thrombus in major vasculature were independent factors of poor prognosis. Survival after resection for HCC with tumor thrombus in the major vasculature is poorer than after resection for HCC without tumor thrombus. However, an aggressive surgical strategy can provide significant survival with comparable morbidity in selected cases, that is, tumor thrombus located in the portal vein only and expected complete resection of the lesions.  相似文献   
75.
The French Renal Epidemiology and Information Network (REIN) registry began in 2002 to provide a tool for public health decision support, evaluation and research related to renal replacement therapies (RRT) for end-stage renal disease (ESRD). It relies on a network of nephrologists, epidemiologists, patients and public health representatives, coordinated regionally and nationally. Continuous registration covers all dialysis and transplanted patients. In 2003, 2070 patients started RRT, 7854 were on dialysis and 7294 lived with a functioning graft in seven regions (with a population of 16.5 million people). The overall crude annual incidence rate of RRT for ESRD was 123 per million population (p.m.p.) with significant differences in age-adjusted rates across regions, from 84 [95% confidence interval (CI): 74-94] to 155 [138-172] p.m.p. The principal causes of ESRD were hypertension (21%) and diabetic (20%) nephropathies. Initial treatment for ESRD was peritoneal dialysis for 15% of patients and a pre-emptive graft for 3%. The one-year survival rate was 81% [79-83] in the cohort of 2002-2003 incident patients. As of December 31, 2003, the overall crude prevalence was 898 [884-913] p.m.p, with 5% of patients receiving peritoneal dialysis, 47% on haemodialysis and 48% with a functioning graft. The experience in these seven regions over these two years clearly shows the feasibility of the REIN registry, which is progressively expanding to cover the entire country.  相似文献   
76.
Nonmelanoma skin cancers (NMSC) are the most common malignant tumors following solid organ transplantation. Risk factors for NMSC mainly include immunosuppression, age, sun exposure and patient phototype. Recent findings have suggested that autosomal dominant polycystic kidney disease (ADPKD) may increase the risk of developing NMSC. We performed a monocenter retrospective study including all kidney recipients between 1985 and 2006 (n = 1019). We studied the incidence of NMSC, solid cancers and post‐transplantation lymphoproliferative disease (PTLD), and analyzed the following parameters: age, gender, phototype, time on dialysis, graft rank, immunosuppressive regimen, history of cancer and kidney disease (ADPKD versus others). Median follow‐up was 5.5 years (range: 0.02–20.6; 79 838 patient‐years). The cumulated incidence of NMSC 10 years after transplantation was 12.7% (9.3% for solid cancers and 3.5% for PTLD). Autosomal dominant polycystic kidney disease and age were risk factors for NMSC (HR 2.63; P < 0.0001 and HR 2.21; P < 0.001, respectively) using univariate analysis. The association between ADPKD and NMSC remained significant after adjustments for age, gender and phototype using multivariate analysis (HR 1.71; P = 0.0145) and for immunosuppressive regimens (P < 0.0001). Autosomal dominant polycystic kidney disease was not a risk factor for the occurrence of solid cancers after transplantation (HR 0.96; P = 0.89). Our findings suggest that ADPKD is an independent risk factor for developing NMSC after kidney transplantation.  相似文献   
77.
Study Type – Diagnostic (non‐consecutive)
Level of Evidence 3b

OBJECTIVE

To describe the clinical and magnetic resonance imaging (MRI) characteristics of vaginal and paraurethral leiomyomas.

PATIENTS AND METHODS

All patients with pathologically confirmed paraurethral and vaginal wall leiomyomas from January 2006 to August 2007 were reviewed. Patients with no preoperative MRI of the pelvis were excluded.

RESULTS

Five patients were identified; all had a firm, smooth, non‐tender, non‐fluctuant mass. MRI showed a well‐circumscribed shape, a homogeneous signal that was hypointense or isointense to muscle on T1‐ and hyperintense or isointense to muscle on T2‐weighted images, and uniform enhancement. In all cases, MRI excluded urethral diverticulae, and pathology showed leiomyoma, of which one had atypical features.

CONCLUSION

Paraurethral and vaginal wall leiomyomas can be identified before surgery with a reasonable degree of certainty, based on their clinical and MRI characteristics.  相似文献   
78.

Rationale

Reflux of gastric and duodenal contents in patients with gastroesophageal reflux disease (GERD) has been postulated as a major cause of complications, such as Barrett’s esophagus or malignant degeneration.

Findings

We present a summary of experimental, clinical, and immunohistochemical studies that show that acid and bile reflux are increased in patients who suffer from GERD, are the key factor in the pathogenesis of Barrett’s esophagus, and are possibly related to the development of esophageal adenocarcinoma.
  相似文献   
79.
Meticulous monitoring and control of the treatment offers patients injured in accidents the best conditions for healing and leads to cost reductions in terms of compensation for injury, vocational aid measures and pensions. The accident and emergency hospital maintained by the employers’ liability insurance association in Hamburg is currently conducting a project entitled “Hand Injuries” in collaboration with the professional association for health services and welfare’s Hamburg regional office, which is aimed at realizing and documenting this aim.  相似文献   
80.
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