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991.
A 76-year-old woman presented with gross hematuria. She had received transurethral resections (TURBT) twice for superficial bladder tumors near the right orifice. All pathologic findings demonstrated low grade superficial transitional cell carcinoma (TCC). Cystoscopy showed the tumor lesions during the follow-up. Bladder tumors were completely harvested and pathologic examination revealed inverted papilloma. However, recurrent tumors were detected at the same location after 4 months' follow up. Although she came to our hospital for the purpose of TURBT, she complained of severe neck pain and was suddenly dead. Autopsy findings showed that dissecting aortic aneurism was the cause of death and the bladder tumor was low grade superficial TCC. The case reported here had a very rare pathologic finding with a history of superficial tumors located in the same areas in the urinary bladder.  相似文献   
992.
OBJECTIVE: To investigate the clinical and immunologic significance of autoantibodies to RNA helicase A (RHA) in patients with systemic rheumatic diseases. METHODS: The study group comprised 1,119 individuals enrolled in the University of Florida Center for Autoimmune Diseases registry from 2000 to 2005. Diagnoses were based on standard criteria. Autoantibodies were analyzed by immunoprecipitation and Western blot assays. RESULTS: Anti-RHA was observed in 17 (6.2%) of 276 patients with systemic lupus erythematosus (SLE), 2 patients with antiphospholipid antibodies, and 3 other patients, but anti-RHA was not observed in any patient with polymyositis/dermatomyositis, systemic sclerosis, rheumatoid arthritis, or Sj?gren's syndrome. Anti-RHA was present in only 2.9% of African American patients, compared with 6.0% of white patients and 12-25% of patients of other races; this was in striking contrast to the frequency of anti-Sm in African American patients (27.2%). Among patients with SLE, anti-RHA was common in young patients (26% of those whose initial visit was at an age younger than 20 years versus 3-4% of those who were initially seen at ages 20-49 years) and at an early stage of disease (23% of those whose first clinic visit was within 1 year of disease onset versus 2-8% of those whose first visit was at least 1 year after disease onset). In 9 of 11 patients, levels of anti-RHA decreased to <10% of the initial value within 9-37 months, while levels of coexisting anti-Ro or anti-Su remained the same. New specificities developed in 2 patients (anti-nuclear RNP and anti-Sm, and anti-ribosomal P, respectively). These data suggest that the level of anti-RHA diminishes over time, and that anti-RHA is regulated via a mechanism different from that for other lupus-related autoantibodies. CONCLUSION: Anti-RHA is a new serologic marker for SLE. It is produced mainly in young non-African Americans at an early stage of their disease. Anti-RHA has a unique tendency to diminish over time. The production of anti-RHA may depend on a process restricted to early SLE, or it may be highly sensitive to treatment.  相似文献   
993.
994.
Atherosclerosis is associated with oxidative stress and inflammation, and upregulation of LOX-1, an endothelial receptor for oxidized LDL (oxLDL). Here, we describe generation of LOX-1 knockout (KO) mice in which binding of oxLDL to aortic endothelium was reduced and endothelium-dependent vasorelaxation preserved after treatment with oxLDL (P<0.01 versus wild-type mice). To address whether endothelial functional preservation might lead to reduction in atherogenesis, we crossed LOX-1 KO mice with LDLR KO mice and fed these mice 4% cholesterol/10% cocoa butter diet for 18 weeks. Atherosclerosis was found to cover 61+/-2% of aorta in the LDLR KO mice, but only 36+/-3% of aorta in the double KO mice. Luminal obstruction and intima thickness were significantly reduced in the double KO mice (versus LDLR KO mice). Expression of redox-sensitive NF-kappaB and the inflammatory marker CD68 in LDLR KO mice was increased (P<0.01 versus wild-type mice), but not in the double KO mice. On the other hand, antiinflammatory cytokine IL-10 expression and superoxide dismutase activity were low in the LDLR KO mice (P<0.01 versus wild-type mice), but not in the double KO mice. Endothelial nitric oxide synthase expression was also preserved in the double KO mice. The proinflammatory signal MAPK P38 was activated in the LDLR KO mice, and LOX-1 deletion reduced this signal. In conclusion, LOX-1 deletion sustains endothelial function leading to a reduction in atherogenesis in association with reduction in proinflammatory and prooxidant signals.  相似文献   
995.
We have recently demonstrated that endogenous erythropoietin (Epo)/Epo receptor (EpoR) system plays an important protective role in hypoxia-induced pulmonary hypertension. However, it remains to be examined whether vascular EpoR system contributes to angiogenesis in response to ischemia. We examined angiogenesis in EpoR(-/-)-rescued mice that lack EpoR in most organs including cardiovascular system except erythroid-lineage cells. Two weeks after femoral artery ligation, blood flow recovery, activation of VEGF/VEGF receptor system, and mobilization of endothelial progenitor cells were all impaired in EpoR(-/-)-rescued mice as compared with wild-type (WT) mice. Bone marrow (BM) transplantation with WT-BM cells in EpoR(-/-)-rescued mice partially but significantly improved blood flow recovery after hindlimb ischemia. The extent of VEGF upregulation and the number of BM-derived cells in ischemic tissue were significantly less in EpoR(-/-)-rescued mice compared with WT mice even after BM reconstitution with WT-BM cells. Similarly, the recovery of blood flow was significantly impaired in recipient EpoR(-/-)-rescued mice that had been transplanted with WT-BM or EpoR(-/-)-rescued-BM as compared with recipient WT mice. Furthermore, the Matrigel implantation assay and aortic ring assay showed that microvessel growth in vitro was significantly reduced in EpoR(-/-)-rescued mice as compared with WT mice. These results indicate that vascular EpoR system also plays an important role in angiogenesis in response to hindlimb ischemia through upregulation of VEGF/VEGF receptor system, both directly by enhancing neovascularization and indirectly by recruiting endothelial progenitor cells and BM-derived proangiogenic cells.  相似文献   
996.
Recent studies suggest that monocytes are the dominant effectors by which rituximab induces cell death in B-cell lymphoma. Because macrophage colony-stimulating factor (M-CSF) can enhance the cytotoxicity of monocytes, the authors examined whether this growth factor can enhance their ability to kill lymphoma cells in vitro. Monocytes derived from a healthy volunteer were cultured for 48 h in the presence or absence of M-CSF. Monocytes stimul ated with M-CSF were significantly more cytotoxic to Daudi B-cell lymphomas than unstimulated monocytes. Flow cytometry revealed that M-CSF increased monocyte expression of Fcgamma receptors III and I by 1.6- and 1.5-fold, whereas the expression of Fcgamma receptor II remained unchanged. These results suggest that pretreatment with M-CSF can improve the therapeutic efficacy of rituximab against intractable CD20(+) lymphoma.  相似文献   
997.
We report a death case of 56-year-old male with unresectable pancreatic cancer. Its diagnosis was locally-advanced cancer of pancreatic head (Stage IVa) in February 2006. However, he desired no medical treatment until obstructive jaundice (T-Bil 25 mg/dL) appeared. In September 2006, endoscopic biliary metallic stenting was performed and the obstructive jaundice had improved. In November 2006, systemic chemotherapy (S-1 +gemcitabine) was performed. After the chemotherapy, vomiting had appeared because of duodenal stenosis. In December 2006, gastrojejunostomy and intraoperative radiotherapy (IORT) were performed, and the dose of oxicodon was decreased. However, in January 2007, he was suddenly in a state of bleeding-shock and died because of intraabdominal bleeding. The autopsy demonstrated the rupture of splenic pseuoaneurysm due to necrotizing pancreatitis of pancreatic tail, and cancer of pancreatic head was almost viable and IORT was not effective.  相似文献   
998.
BACKGROUND: Currently, the inability to achieve successful islet transplantation from one donor to one recipient is a major obstacle facing clinical islet transplantation. We herein determined whether this limitation could be overcome by targeting pro-inflammatory cytokines with the prevention of immediate islet graft loss in association with engraftment in mice. METHODS: Isolated islets were grafted into the liver of streptozotocin-induced diabetic mice and the role of proinflammatory cytokines in the engraftment of islets was evaluated with the use of interferon (IFN)-gamma-/- mice and monoclonal antibodies against proinflammatory cytokines. RESULTS: Hyperglycemia in streptozotocin-induced diabetic mice receiving 200 syngenic islets, which were isolated from a single mouse pancreas, was ameliorated when IFN-gamma-/-, but not wild-type mice, were used as recipients. The treatment with anti-IFN-gamma antibody produced normoglycemia in diabetic wild-type mice receiving 200, but not 100 islets. However, when anti-tumor necrosis factor-alpha and anti-interleukin-1beta antibodies were administered in conjunction with anti-IFN-gamma antibody, wild-type diabetic mice receiving 100 islets became normoglycemic after transplantation. In addition, the favorable effect of the combined use of antibodies was similarly achieved in mice receiving islet allografts when rejection was prevented with anti-CD4 antibody treatment. CONCLUSIONS: These findings clearly demonstrate that successful islet transplantation from one donor to two recipients is feasible by targeting pro-inflammatory cytokines in mice, thus suggesting a potential application in clinical islet transplantation if similar mechanisms of islet graft loss could be mediated in humans.  相似文献   
999.
Lithium has been proven to be effective in the therapy of bipolar disorder, but its mechanism of pharmacological action is not clearly defined. We examined the effects of lithium on voltage-dependent Na(+) channels, nicotinic acetylcholine receptors, and voltage-dependent Ca(2+) channels, as well as catecholamine secretion in cultured bovine adrenal chromaffin cells. Lithium chloride (LiCl) reduced veratridine-induced (22)Na(+) influx in a concentration-dependent manner, even in the presence of ouabain, an inhibitor of Na(+), K(+)-ATPase. Glycogen synthase kinase-3 (GSK-3) inhibitors (SB216763, SB415286 or the GSK-3 inhibitor IX) did not affect veratridine-induced (22)Na(+) influx, as well as inhibitory effect of LiCl on veratridine-induced (22)Na(+) influx. Enhancement of veratridine (site 2 toxin)-induced (22)Na(+) influx caused by alpha-scorpion venom (site 3 toxin), beta-scorpion venom (site 4 toxin), or Ptychodiscus brevis toxin-3 (site 5 toxin), still occurred in the presence of LiCl in the same manner as in the control cells. LiCl also reduced veratridine-induced (45)Ca(2+) influx and catecholamine secretion. In contrast, LiCl (< or = 30 mM) had no effect on nicotine-induced (22)Na(+) influx, (45)Ca(2+) influx and catecholamine secretion, as well as on high K(+)-induced (45)Ca(2+) influx and catecholamine secretion. Chronic treatment with LiCl at 100mM (but not at < or = 30 mM) significantly reduced cell viability in a time-dependent manner. These results suggest that lithium selectively inhibits Na(+) influx thorough Na(+) channels and subsequent Ca(2+) influx and catecholamine secretion, independent of GSK-3 inhibition.  相似文献   
1000.
Objective We investigated the association between mycophenolic acid (MPA) pharmacokinetics and organic anion-transporting polypeptide (OATP/SLCO)1B1, 1B3, 2B1 and multidrug resistance-association protein 2 (MRP2/ABCC2) genetic polymorphisms and diarrhea. Methods Eighty-seven renal allograft recipients were given repeated doses of mycophenolate mofetil every 12 h at a designated time (09:00 and 21:00). The pharmacokinetics of MPA were analyzed on day 28 posttransplantation. Results The dose-adjusted area under the cuve (AUC)6–12 of MPA, an estimate of enterohepatic recirculation, was greater in SLCO1B3 T334G GG (or G699A AA) carriers than in TT carriers (or G699A GG) (40 vs. 25 ng·h/mL per milligram, respectively, P = 0.0497). None of the polymorphism of SLCO1B1, SLCO2B1, or ABCC2 C-24T were associated with MPA pharmacokinetics or diarrhea. However, the oral clearance of MPA in recipients having both the SLCO1B3 T334G GG genotype and the ABCC2 C-24T T allele was significantly lower than in patients having both the SLCO1B3 T334G TT and ABCC2 C-24T CC genotypes (0.15 vs. 0.18 L/h per kilogram, respectively, P = 0.0010). Conclusions MPA excretion into bile in patients with SLCO1B3 T334G GG (or G699A AA) was higher than in those with T334G TT (or G699A GG), probably resulting in a higher AUC6–12 value of MPA. MPA uptake into hepatocytes and excretion into bile at first pass may be greater in SLCO1B3 T334G GG carriers than in TT carriers. In addition, the ABCC2 C-24T polymorphism also seems to be associated with enhanced enterohepatic circulation of MPA. The SLCO1B3 and ABCC2 transporters rather than uridine diphosphate-glucuronosyltransferase (UGT) may partly affect interindividual variety in plasma MPA concentration.  相似文献   
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