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71.
72.
TEL-TRKC is a fusion gene generated by chromosomal translocation and encodes an activated tyrosine kinase. Uniquely, it is found in both solid tumors and leukemia. However, a single exon difference (in TEL) in TEL-TRKC fusions is associated with the two sets of cancer phenotypes. We expressed the two TEL-TRKC variants in vivo by using the 3' regulatory element of SCL that is selectively active in a subset of mesodermal cell lineages, including endothelial and hematopoietic stem cells and progenitors. The leukemia form of TEL-TRKC (-exon 5 of TEL) enhanced hematopoietic stem cell renewal and initiated leukemia. In contrast, the TEL-TRKC solid tumor variant (+ TEL exon 5) elicited an embryonic lethal phenotype with impairment of both angiogenesis and hematopoiesis indicative of an effect at the level of the hemangioblasts. The ability of TEL-TRKC to repress expression of Flk1, a critical regulator of early endothelial and hematopoietic cells, depended on TEL exon 5. These data indicate that related oncogenic fusion proteins similarly expressed in a hierarchy of early stem cells can have selective, cell type-specific developmental impacts.  相似文献   
73.
BackgroundWe conducted this prospective study to evaluate the efficacy of percutaneous catheter drainage as a minimally invasive treatment in the management of symptomatic bile leak following biliary injuries associated with laparoscopic cholecystectomy.MethodsTwenty two patients with symptomatic bile leak following laparoscopic cholecystectomy underwent percutaneous drainage of the bile collection under ultrasound control. In patients with jaundice and in those with persistent drainage, endoscopic retrograde cholecysto-pancreatography (ERCP) was performed immediately for diagnostic and for therapeutic intervention when appropriate. In other patients, ERCP was performed 4–6 weeks after the discharge from the hospital to document the healing of the leaking site.ResultsFive patients with jaundice were initially treated by a combination of endoscopic plus percutaneous drainage. One of them required surgical treatment following diagnosis of a major duct injury. The other 17 were treated by percutaneous drainage initially and for 14 of them it was definitive treatment. Three patients required sphincterotomy as additional treatment for stopping the leak. There were no complications related to the percutaneous drainage procedure.ConclusionsMost patients with bile leakage can be managed successfully by percutaneous drainage. If biliary output does not decrease, endoscopy is needed. In patients with jaundice endoscopic diagnostic and therapeutic procedures should be performed immediately.  相似文献   
74.
The prothrombotic state in type 1 diabetes mellitus (T1DM) has been reported as a plausible cause of vascular complications. Rotational thromboelastometry (ROTEM) assay enables the global assessment of coagulation status. This study aimed to assess hypercoagulability in children with T1DM using ROTEM. A total of 43 T1DM children (20 females and 23 males) aged 2–18 years and age- and sex-matched 30 healthy control subjects were enrolled in the study group. ROTEM assays [intrinsic TEM (INTEM) and extrinsic TEM (EXTEM)] were used to measure and analyze coagulation time (CT), clot formation time, maximum clot firmness (MCF). Glycated hemoglobin levels (HbA1c), diabetic complications, platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, and dimerized plasmin fragment D (D-dimer) were determined in the study group. The mean duration of T1DM diagnosis was 3.15 ± 2.49 years, and the mean HbA1c level was 8.94 ± 1.88% (74.29 ± 20.59 mmol/mol). None of the patients had macrovascular complications. Nephropathy was present in five patients. In the T1DM group, EXTEM-CT [80.00 (66.75?108.50)] was significantly lower, and EXTEM-MCF [65.00 (64.00?70.00)] and INTEM-MCF [65.00 (62.00?68.00)] were significantly higher than in the controls (p < 0.001, p = 0.026, and p = 0.004, respectively). However, the duration of T1DM and the degree of metabolic control had no influence on these parameters. Platelet count, PT, aPTT, fibrinogen and D-dimer levels were comparable between the diabetic patients and the control group. There were statistically significant correlations between fibrinogen level and INTEM-MCF and EXTEM-MCF (p < 0.001, p = 0.002 and r = 0.545, r = 0.454, respectively) This study shows that decreased levels of CT and increased levels of MCF suggest hypercoagulability in patients with T1DM. Further studies are needed to confirm our findings on a larger number of diabetic patients.  相似文献   
75.
Systemic lupus erythematosus (SLE) is associated with severe and premature cardiovascular disease, which cannot be explained by traditional risk factors alone. This study aims to investigate novel cardiovascular risk factors and cardiac event predictors in inactive SLE female patients who do not have any major cardiovascular risk factors. Twenty-five inactive (SLE disease activity index score <4) SLE female patients and 22 healthy control women were studied. SLE patients with a history of diabetes mellitus, hypertension, hyperlipidemia, smoking, or coronary artery disease (CAD) were excluded. Venous blood samples were analyzed for lipid subfractions and novel cardiovascular risk factors such as lipoprotein (a), homocysteine, fibrinogen, high-sensitivity C-reactive protein (hs-CRP), and serum amyloid A (SAA) levels. Endothelial dysfunction was assessed by flow-mediated dilatation (FMD) from the brachial artery at baseline and during reactive hyperemia. SLE patients and controls were similar in terms of age (40±10 years vs 38±10 years, p = NS). No significant difference was found between the groups regarding family history of premature CAD, blood pressure, body mass index, lipoprotein (a), homocysteine, fibrinogen, SAA, apoprotein A-1 and B levels. Compared with the controls, SLE patients had higher levels of hs-CRP [median (range): 1.82 (0.02–0.98) vs 0.68 (0.02–0.35), p=0.04]. FMD was lower in SLE patients than controls (7.1±2.1 vs 11.4±1.2%, p<0.001). Increased levels of hs-CRP and decreased FMD were found in inactive SLE patients. Increased hs-CRP levels may reflect ongoing low-grade inflammation that could be a cause of impaired FMD in SLE patients. These findings suggest that SLE patients without traditional major cardiovascular risk factors may have increased risk of cardiovascular disease and future cardiac events.  相似文献   
76.
AIM: To investigate the diagnostic efficacy of leukocyte esterase and nitrite reagent strips for bedside diagnosis of spontaneous bacterial peritonitis (SBP). METHODS: A total of 63 consecutive patients with cirrhotic ascites (38 male, 25 female) tested between April 2005 and July 2006 were included in the study. Bedside reagent strip testing was performed on ascitic fluid and the results compared to manual cell counting and ascitic fluid culture. SBP was defined as having a polymorphonuclear ascites count of ≥ 250/mm^3. RESULTS: Fifteen samples showed SBP. The sensitivity, specificity, positive and negative predictive values of the leukocyte esterase reagent strips were; 93%, 100%, 100%, and 98%, respectively. The sensitivity, specificity, positive and negative predictive value of the nitrite reagent strips were 13%, 93%, 40%, and 77%, respectively. The combination of leukocyte esterase and nitrite reagents strips did not yield statistically significant effects on diagnostic accuracy. CONCLUSION: Leukocyte esterase reagent strips may provide a rapid, bedside diagnostic test for SBP.  相似文献   
77.
Background and Aim: Patients with primary sclerosing cholangitis (PSC) who develop cholangiocarcinoma (CCA) have a median survival of less than 6 months. In half of cases, PSC and CCA will be diagnosed either concurrently or within a year of one another. The aim of the present study is to demonstrate that the degree of biochemical liver dysfunction is associated with concomitant or impending CCA. Methods: We did a chart review of patients diagnosed with PSC and CCA up to 18 months from presentation (“CCA” group) as well as patients with PSC that underwent transplantation with no sign of CCA in their explanted liver (“nCCA” group). Along with demographic data and follow-up length, we recorded their presenting liver function tests, including alanine and aspartate aminotransferases (ALT, AST), total bilirubin (TBil), alkaline phosphatase (ALP), international normalization ratio (INR), and serum Ca 19-9 levels. Differences between mean values of the two groups were analyzed with a student’s t-test. Results: Twenty-four patients were included. The “CCA” group consisted of eight patients, and the “non-CCA” group had 16 patients. There was no significant difference between the two groups in their presenting values of ALT, ALP, or serum Ca 19-9. However, the “CCA” group had significantly higher levels of AST, TBil, and INR. Conclusion: Patients with PSC and concurrent or impending CCA appear to exhibit significantly greater biochemical liver dysfunction than those who do not develop CCA. Therefore, newly-diagnosed PSC patients presenting with these findings may warrant more rigorous evaluation.  相似文献   
78.
Pseudoexfoliation syndrome (PEX) is the most common clinical precursor of open-angle glaucoma. Recent studies have shown that pseudoexfoliative material is widely distributed throughout the body, including blood vessels. The aim of our study was to evaluate endothelial function in the brachial artery of patients with pseudoexfoliation syndrome. We prospectively examined 23 patients with PEX (mean age, 70 +/- 8 years) and 20 healthy age- and sex-matched individuals (mean age, 68 +/- 9 years) as a control group. Brachial artery endothelial function was assessed by vascular response to reactive hyperemia (flow-mediated dilation (FMD) and sublingual nitroglycerin (NTG-mediated dilation) using high-resolution ultrasound. Flow-mediated and NTG-induced dilation were expressed as the percent change in diameter after reactive hyperemia and after NTG administration relative to the baseline value, respectively. Patients with cardiovascular disease and other conditions associated with endothelial dysfunction were excluded. When compared with controls, patients with PEX had significantly lower flow-mediated dilation (4.5 +/- 2.8 versus 8.2 +/- 3.7, P = 0.01) and NTG-mediated dilation (10.9 +/- 3.1 versus 15.8 +/- 3.8, P = 0.0001). Flow-mediated dilation and NTG-mediated dilation were similar in PEX patients with glaucoma (n = 11) and without glaucoma (n = 12). Flow-mediated and NTG-mediated dilation did not correlate with any measured parameter in any patient or control subject. The findings indicate that systemic endothelial function is impaired in PEX syndrome patients.  相似文献   
79.
OBJECTIVES: The purpose of our study was to evaluate the significance of polymorphisms in HLA class II genes in coronary artery ectasia (CAE) patients. METHODS AND RESULTS: Twenty-six patients with CAE without associated cardiac defects were enrolled in the study. CAE was defined as luminal dilation of 1.5- to 2.0-fold of normal limits. Ninety-five healthy subjects who were donors for different organ transplantations, were chosen as control group. Physical examination, electrocardiography and chest X-ray were completely normal in these cases. Both the patients and the control group were screened and compared for their HLA class II genotypes. HLA-DR B1*13, DR16, DQ2 and DQ5 genotypes were significantly more frequent in the patient group.When the known risk factors of coronary heart disease were compared in the patients carrying these genotypes with the non-carrying group, no significant differences were encountered. CONCLUSIONS: HLA-DR B1*13, DR16, DQ2 and DQ5 may be associated with the pathogenesis and increase the risk of CAE.  相似文献   
80.
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