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61.
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   
62.
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   
63.
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   
64.
Management of upper gastrointestinal bleeding because of erosion of vessels by esophageal cancer may be challenging. We present herein the angiographic images of a 49-year-old patient who was admitted with massive bleeding from a tumor-eroded inferior thyroid artery. Attempts to control the bleeding by means of flexible endoscopy and insertion of a Sengstaken–Blakemore tube had failed. The diagnosis was impressively demonstrated by multislice computed tomography with intravenous contrast in the arterial phase and multiplanar reconstructions (computed tomography angiography) and by digital subtraction angiography. The bleeding was successfully treated with superselective catheterization and coiling of the eroded vessel.  相似文献   
65.
Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have been proven to be an effective treatment modality for selected patients with peritoneal surface malignancies. The most common surgical complications after CRS and HIPEC are anastomotic leakage, intestinal obstruction and peripancreatitis. This case report presents two patients with early and late postoperative diaphragmatic hernia after CRS and HIPEC. One patient that initially had pseudomyxoma peritonei complained of persistent chest pain and dyspeptic disorder after peritonectomy and HIPEC and underwent reoperation due to a left diaphragmatic hernia containing the splenocolic flexure. The other patient had gastric cancer and peritoneal carcinomatosis and developed anastomotic leakage of the transverse colon anastomosis and pleural empyema. Stripping of the diaphragm is often performed during CRS, sometimes combined with diaphragmatic resection. A herniation through a diaphragmatic defect is rarely diagnosed during either the early or late postoperative period. Direct suture of the defect or closure with synthetic or biological tissue are possible surgical techniques for repair with a good prognosis.  相似文献   
66.
Secondary protein‐losing enteropathy (PLE) is a rare complication following pediatric liver transplantation (LT), mostly related to venous outflow obstruction of the liver. Here, we discuss a thus far unknown cause of secondary PLE following pediatric LT. A 7‐month‐old boy underwent LT with biliary anastomosis using a Roux‐en‐Y jejunal loop. Eleven months later he developed PLE. Routine diagnostic workup was negative. No hepatic outflow obstruction was detected during catheterization. Although the hepatic venous pressure gradient was slightly increased (10 mm Hg), there were no clinical signs of portal hypertension. Albumin scintigraphy with specific early recordings suggested focal albumin intestinal entry in the jejunal Roux‐en‐Y loop. Local bacterial overgrowth or local lymphangiectasia, possibly due to (venous) congestion, was considered. Treatment with metronidazole did not improve albumin loss. Next, surgical revision of the jejunal Roux‐en‐Y loop was performed. The explanted loop contained a small abnormal area with a thin hyperemic mucosa, near the former anastomosis. Histopathological analysis showed changes both in the blood vessels and the lymphatic vessels with focal deeper chronic active inflammation resulting in congestion of vessels, hampering lymphatic outflow leading to lymphangiectasia and patchy distortion of lymphatic vessels. Following surgical revision, secondary PLE disappeared, up to now, 1.5 year post revision.  相似文献   
67.
BackgroundThe prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in cystic fibrosis (CF) patients has increased and MRSA seems to be associated with a poorer prognosis. The aim of this study was to assess the prevalence and clinical consequences of MRSA and methicillin-susceptible Staphylococcus aureus (MSSA), associated or not associated with Pseudomonas aeruginosa (PA).MethodsIn a retrospective study on 419 sputum producer patients (293 adults and 126 children > 7 years of age), we recorded patient characteristics, lung function, nutritional status, IV antibiotics and hospitalisations, the presence of SA and/or PA and FEV1 decline over 2 years.ResultsSA was found in 72% of the patients: MSSA in 68.2% of children and 48.8% of adults; MRSA in 17.5% of children and 17.8% of adults. Sixty percent of MRSA patients and 60.4% of MSSA patients also harboured PA. The rate of deterioration of clinical status of the various groups, as assessed from respiratory function, IV antibiotic courses and hospitalisations, increased in the order: no SA/no PA, MSSA alone, MRSA alone, MSSA/PA, MRSA/PA, and PA alone. Nutritional status did not differ between groups. Results were roughly similar for children and adults. The yearly FEV1 decline was significantly higher only for MRSA/PA patients (p = 0.03) compared to no SA/no PA patients.ConclusionClinical condition of CF patients with MSSA only or MRSA only appeared similar, whereas MRSA/PA patients had more severe respiratory function than MSSA/PA patients. In CF patients, MRSA might be more deleterious than MSSA only when associated with PA.  相似文献   
68.
John H 《The Journal of urology》2004,171(5):1866-70; discussion 1869-70
PURPOSE: A new bulbourethral sling procedure is proposed for patients with post-radical prostatectomy incontinence. MATERIAL AND METHODS: Bulbourethral composite suspension was performed in 16 consecutive patients, of whom 6 (38%) had severe stress incontinence and depended on a condom urinal catheter. Urinary stress incontinence was assessed preoperatively by a modified pad test, urethrocystoscopy and urodynamic evaluation. The procedure was performed with a longitudinal perineal and a transverse suprapubic incision with the patient under regional anesthesia. We placed a porcine dermis for urethral protection and a polypropylene retropubic sling, which was tied suprapubically with the patient coughing and during retrograde urethral closure pressure monitoring at 60 cm H2O. RESULTS: Preoperative evaluation excluded detrusor instability and urethral stricture. The polypropylene band was placed without neurogenic or vascular complications. All patients had primary wound healing. Patients reported only minimal postoperative pain. Clinical followup was performed a median of 14 months postoperatively (range 6 to 32). Of the 16 patients 11 (69%) were completely dry and 1 (6%) reported improved continence, while 4 (25%) had no benefit, including 2 who underwent an artificial sphincter procedure. Preoperative mean daily pad use decreased from 7 (range 2 to 12) to 1 (range 0 to 10) postoperatively (p = 0.0004) and postoperative quality of life improved significantly (p <0.0001). CONCLUSIONS: Bulbourethral composite suspension is a new, efficient operative sling technique in patients with severe post-prostatectomy stress urinary continence. Because morbidity and complications are low, this new technique may become an alternative to artificial urinary sphincter implantation. Long-term observation of urethral and detrusor function is necessary to elucidate the specific contribution of bulbourethral composite suspension in restoring urinary continence after radical prostatectomy.  相似文献   
69.
Cases of recurrence of breast cancer can pose considerable diagnostic and therapeutic challenges for the oncologic team. The prognosis and management decisions are based on knowledge of the true extent of disease. Conventional staging methods, including physical examination, assessment of levels of tumor markers, cross-sectional imaging, and bone scintigraphy, may not reliably demonstrate the extent of disease in all cases. Physical examination and cross-sectional imaging (computed tomography [CT] or magnetic resonance imaging) can be problematic because (a) the sequelae of previous surgery and radiation therapy can be difficult to distinguish from recurrent neoplasms and (b) early metastatic disease (small lesions) can be difficult to distinguish from benign lesions that are too small to characterize. Positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) can help clarify inconclusive findings from physical examination and cross-sectional imaging. FDG PET is more sensitive than CT in detection of lymphatic spread of disease to locoregional and mediastinal nodes. Metastases at distant sites including the lung, bone, and the liver are also readily detected at FDG PET. FDG PET has been proved accurate in restaging cases of recurrent breast cancer and will likely aid in directing therapy in these cases.  相似文献   
70.
A tool was developed for automated intrapatient comparison of brain SPECT images, with specific emphasis on gray-level normalization. METHODS: Ictal and interictal (99m)Tc-ethyl cysteinate dimer SPECT images were acquired for 6 children with partial epilepsy (age range, 2-10 y). For each patient, 3-dimensional rigid geometric ictal-to-interictal image registration optimizing different classic criteria (correlation coefficient, ratio uniformity) in a multiscale translation-rotation 6-parameter space was first performed. Gray-level normalization was then performed with different methods, using a 1- or 2-parameter linear model. In the 1-parameter case, the scaling factor was equal to the interictal-to-ictal ratio of the maximum, mean, or median values calculated within different reference volumes (whole brain or cerebellum) or obtained by linear regression between ictal and interictal counts in the brain or by maximizing a robust criterion, the number of deterministic sign changes in the subtraction images. In the 2-parameter case, the scaling factor and additive constant were estimated using these last 2 methods. For each patient, registration validity and normalization plausibility were assessed by considering the correlation scatterplot together with the different normalization lines and by comparing interictal and registered normalized ictal images using a twin display (with isocontours) in the 3 orthogonal planes. Three-dimensional volumes of interest could be selected on coupled interictal-subtraction images for further focused numeric comparison. RESULTS: After a satisfactory and stable geometric registration with both criteria, the different normalization methods led to similar subtraction images for 5 of 6 patients, except the maxima ratio, which gave noticeably different results in 2 patients. For the remaining patient, with highly dissimilar ictal-interictal images, the maxima ratio normalization was obviously wrong and the other 1-parameter methods probably better depicted the data than did the 2-parameter methods. CONCLUSION: When comparing intrapatient brain SPECT images, one should be aware of the potential impact of the gray-level normalization method on clinical interpretation. For ictal-interictal images, simple robust scaling should be recommended. In particular, image maximum should generally not be considered a valid reference, and no additive constant is needed in the linear gray-level normalization model.  相似文献   
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