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81.
An 80-year-old man underwent rectal resection and insertion of a central venous catheter through the left subclavian vein 16 years earlier. Following surgery, he developed edema of his left upper limb that became exacerbated and infected. Computed tomography showed occlusion of the subclavian vein and multiple arteriovenous shunts from the branches of the axillary artery to the venous sac of the axillary vein. Angiography confirmed numerous shunts between the branches of the axillary artery and vein and dilated collateral veins. Embolization of the venous sac was performed using coils, alcohol, and glue. Postprocedural angiography showed complete eradication of the nidus.  相似文献   
82.
A tyrosine kinase adaptor protein containing pleckstrin homology and SH2 domains (APS) is rapidly and strongly tyrosine phosphorylated by insulin receptor kinase upon insulin stimulation. The function of APS in insulin signaling has heretofore remained unknown. APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. Plasma insulin levels during fasting and in the intraperitoneal glucose tolerance test were lower in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin. However, overexpression of wild-type or dominant-negative APS in 3T3L1 adipocytes did not affect insulin receptor numbers, phosphorylations of insulin receptor, insulin receptor substrate-1, or Akt and mitogen-activated protein kinase. The glucose uptake and GLUT4 translocation were not affected by insulin stimulation in these cells. Nevertheless, the insulin-stimulated glucose transport in isolated adipocytes of APS(-/-) mice was increased over that of APS(+/+) mice. APS(-/-) mice also showed increased serum levels of leptin and adiponectin, which might explain the increased insulin sensitivity of adipocytes.  相似文献   
83.
BACKGROUND: Pancreaticobiliary maljunction (PBM) is frequently associated with congenital choledochal cyst (CCBD), but differs in embryonic cause and clinical features. It is thought to develop as a misarrangement of the embryonic connections in the pancreaticobiliary ductal system, with the terminal bile duct joined to one of the ducts of the ventral pancreas. Clinical aspects are intermittent abdominal pain, relapsing acute pancreatitis, jaundice, cholangitis, and gallbladder cancer. In patients with PBM and CCBD, primary bile duct stones, acute cholangitis, and bile duct cancer are considered to result from cholestasis, regurgitation of pancreatic juice, and reciprocal reflux of bile and pancreatic juice. The mixture of bile and pancreatic juice due to recipocal reflex very likely plays an important role in biliary carcinogenesis. PATIENTS AND METHODS: We reviewed the pathophysiological and clinical aspects and biliary carcinogenesis in 250 PBM patients (169 with benign hepatobiliary and pancreatic disease, 81 with malignancy). RESULTS: PBM patients show elevated cellular proliferation activity in the gallbladder epithelia. A number of oncogenes and tumor suppressor genes have been identified and implicated in carcinogenesis, particularly the K- ras oncogene and the p53 suppressor gene. Some K- ras mutations do not appear essential for hyperplasia but may be an early event in carcinogenesis. The p53 mutations are involved in carcinogenesis in the biliary epithelium in PBM patients.  相似文献   
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85.
The purpose of this study was to evaluate the durability of one-bottle self-etching adhesive during long-term water-storage testing. Resin–dentin bonded specimens were prepared using four commercially available one-bottle self-etching adhesives. The specimens were sectioned perpendicular to the adhesive interface to produce beam-shaped specimens that were stored in water for 24 h (control group) and 100, 200, and 300 d (experimental groups). After each storage period, the beams were subjected to a microtensile bond test. After the bond test, fractured surfaces were examined using a scanning electron microscope. In addition, interfacial observations of the silver tracer were performed using the secondary and back-scatter modes of the scanning electron microscope. The bond strength of all tested adhesives decreased significantly after 100 or more days in water. The interfacial observations showed an oxygen-inhibition zone as electron lucent in the adhesive–composite border in control specimens, displaying silver impregnation with breakage after aging. The deterioration of the oxygen-inhibition zone in the adhesive–resin composite junction resulted in a decrease in bond strength after 100 d in water for one-bottle self-etching adhesives.  相似文献   
86.
Chromosomal and microsatellite instability in sporadic gastric cancer   总被引:5,自引:0,他引:5  
BACKGROUND: Gastric cancer can progress through two pathways of genomic instability: chromosomal (CIN) and microsatellite instability (MSI). It is hypothesized that these two pathways are not always independent and that some tumors show overlap between these two mechanisms. METHODS: A total of 98 sporadic gastric cancers were classified based on their MSI status, using microsatellite assay with BAT26. Evidence for CIN was investigated by identifying loss of heterozygosity (LOH) events on chromosome arms, 5q, 10p, 17p, 17q, and 18q, which are regions harboring tumor suppressor genes that are significant in gastric cancer development. RESULTS: Twelve tumors (12%) showed high-frequency MSI (MSI-H). Overall, 43 of the tumors (44%) had at least one LOH event, with most frequent chromosomal losses observed on 10p and 18q (30%, respectively), followed by 5q (21%), 17p (14%), and 17q (12%). Interestingly, overlap was observed between CIN and MSI pathways. Of 43 cancers with LOH events, four (9%) were also MSI-H. It was also found that 48% of cancers without MSI-H had no LOH events identified, comprising a subgroup of tumors that were not representative of either of these two pathways of genomic instability. CONCLUSION: These results suggest that molecular mechanisms of genomic instability are not necessarily independent and may not be fully defined by either the MSI or CIN pathways in sporadic gastric cancers.  相似文献   
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88.

Background and Aims

Sodium-dependent glucose transporter-2 (SGLT-2) inhibitors, which are anti-diabetic drugs, reportedly decrease the incidence of cardiovascular events in high-risk patients with cardiovascular diseases, and thus chronic heart failure (CHF). SGLT-2 inhibitors also decrease albuminuria in patients with type 2 diabetes mellitus (T2D). Since albuminuria is a biomarker of not only chronic kidney disease but also cardiovascular events, we hypothesized that, among T2D patients with CHF, SGLT-2 inhibitors will decrease the extent of albuminuria and also improve CHF concomitantly.

Methods

DAPPER (UMIN000025102) is a multicenter, randomized, open-labeled, parallel-group, standard treatment-controlled study, which is designed to evaluate whether dapagliflozin, one of the SGLT-2 inhibitors, decreases albuminuria in T2D patients with CHF and exerts cardioprotective effects on the failing heart. The patients are randomized to either of the dapagliflozin (5 or 10 mg, once daily orally) or control group (administration of anti-diabetic drugs administered other than SGLT 2 inhibitors). The estimated number of patients that need to be enrolled is 446 in total (223 in each group). The primary objective is the changes in the urinary albumin-to-creatinine ratio from the baseline after 2-year treatment. The key secondary objectives are (1) the safety of dapagliflozin and (2) the cardiovascular and renal efficacies of dapagliflozin.

Conclusion and Perspectives

DAPPER study investigates whether dapagliflozin decreases albuminuria and exerts beneficial effects on the failing heart in T2D patients. (UMIN000025102).
  相似文献   
89.
Apolipoprotein (apo)CIII predicts risk for coronary heart disease. We recently reported that apoCIII directly activates human monocytes. Recent evidence indicates that toll-like receptor (TLR)2 can contribute to atherogenesis through transduction of inflammatory signals. Here, we tested the hypothesis that apoCIII activates human monocytoid THP-1 cells through TLR2. ApoCIII induced the association of TLR2 with myeloid differentiation factor 88, activated nuclear factor (NF)-kappaB in THP-1 cells, and increased their adhesion to human umbilical vein endothelial cells (HUVECs). Anti-TLR2 blocking antibody, but not anti-TLR4 blocking antibody or isotype-matched IgG, inhibited these processes (P<0.05). ApoCIII bound with high affinity to human recombinant TLR2 protein and showed a significantly higher (P<0.05) and saturable binding to 293 cells overexpressing human TLR2 than to parental 293 cells with no endogenous TLR2. Overexpression of TLR2 in 293 cells augmented apoCIII-induced NF-kappaB activation and beta(1) integrin expression, processes inhibited by anti-apoCIII antibody as well as anti-TLR2 antibody. Exposure of peripheral blood monocytes isolated from C57BL/6 (wild-type) mice to apoCIII activated their NF-kappaB and increased their adhesiveness to HUVECs. In contrast, apoCIII did not activate monocytes from TLR2-deficient mice. Finally, intravenous administration to C57BL/6 mice of apoCIII-rich very-low-density lipoprotein (VLDL), but not of apoCIII-deficient VLDL, activated monocytes and increased their adhesiveness to HUVECs, processes attenuated by anti-TLR2 or anti-apoCIII antibody. ApoCIII-rich VLDL did not activate monocytes from TLR2-deficient mice. In conclusion, apoCIII activated monocytes at least partly through a TLR2-dependent pathway. The present study identifies a novel mechanism for proinflammatory and proatherogenic effects of apoCIII and a role for TLR2 in atherosclerosis induced by atherogenic lipoproteins.  相似文献   
90.
We endoscopically measured pressures of the pancreatic duct (PP) and the sphincter of Oddi (SO) in patients with alcoholic (ALCP, n = 10), gallstone-associated (GSCP, n = 7), and idiopathic chronic pancreatitis (ICP, n = 21), and in 20 controls. The PP was significantly higher in the patients with ALCP (55.7 +/- 28.9 mm Hg), GSCP (33.6 +/- 16.2 mm Hg), or ICP (44.5 +/- 25.8 mm Hg) than in the controls (16.2 +/- 8.7 mm Hg), but there was no significant difference between ALCP, GSCP, and ICP. There was no significant difference between control subjects and ICP in the motility of SO. In ICP, there was no correlation between the PP and the motility of SO. In ALCP and GSCP, the frequencies of the papillary sphincter waves were significantly higher than in normal subjects, and there were correlations between the PP and the motility of SO. These data suggest that increased pancreatic ductal pressure in GSCP with papillitis or ALCP may be due in part to papillary dysfunction, but not in ICP.  相似文献   
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