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11.
Thrombotic microangiopathy (TMA) may develop after living donor liver transplantation (LDLT), but the mechanism is not fully understood. We retrospectively analyzed all patients undergoing LDLT at our center, including TMA patients, to elucidate the clinical characteristics and presentation and to determine which patients have a higher risk of occurrence of TMA. In all, 57 adult patients were reviewed after LDLT at our institution. TMA was diagnosed by sudden and severe thrombocytopenia, followed by hemolytic anemia with fractionated erythrocytes in the blood smear. Clinical features were compared between the TMA group and the non-TMA group. Of the 57 patients, 4 were diagnosed with posttransplantation TMA. ABO blood group (ABO)-incompatibility, cyclophosphamide (CPA), and recipient blood group (type O) were closely correlated with the occurrence of TMA. Thrombocytopenia appeared 1 to 5 days before hemolytic anemia. Coagulative function markers stayed at the same level after TMA, while marked elevation was shown in fibrinolytic function markers such as plasminogen activator inhibitor type 1 (PAI-1). TMA occurred at a higher prevalence in ABO-incompatible graft recipients. Additional factors associated with ABO-incompatible transplantation, such as an overdose of immunosuppressants, may affect the likelihood of TMA. Sudden and severe thrombocytopenia presented before hemolytic anemia and the serum levels of PAI-1 correlated well with the clinical course of TMA. In conclusion, early recognition of thrombocytopenia and elevation of PAI-1 is crucial to diagnose TMA especially in ABO-incompatible LDLT.  相似文献   
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Recent studies have shown that hyperbaric oxygen therapy (HBOT) reduces neutrophil endothelial adherence in venules and also blocks the progressive arteriolar vasoconstriction associated with ischemia-reperfusion (I-R) injury in the extremities and the brain. In order to elucidate the effects of HBOT after I-R in digestive organs, particularly in the liver, we evaluated the following: 1) the relationship between timing of HBOT and tissue damage; and 2) HBOT's effects on neutrophil sequestration. Using a hepatic I-R (45 minute) model in male rats, survival rate, liver tissue damage, and neutrophil accumulation within the sinusoids in the HBOT-treated group (Group H) were compared to those in the nontreated group (Group C). For the HBOT-treated group, HBOT was administered as 100% oxygen, at 2.5 atm absolute, for 60 minutes. When HBOT was given 30 minute after I-R, the survival rate was much better in Group H than in Group C. HBOT performed within 3 hours of I-R markedly suppressed increases in the malondialdehyde level in tissues of the liver and lessened the congestion in the sinusoids. In addition, HBOT just after I-R caused decreased number of cells stained by the naphthol AS-D chloroacetate esterase infiltrating into the sinusoids. HBOT 3 hours after reperfusion, however, showed no clear effects upon neutrophil sequestration compared to Group C. These results indicate that HBOT performed within 3 hours of I-R alleviates hepatic dysfunction and improves the survival rate after I-R. Herein, we propose 1 possible mechanism for these beneficial effects: early HBOT given before neutrophil-mediated injury phase may suppress the accumulation of neutrophils after I-R. In conclusion, we believe that the present study should lead to an improved understanding of HBOT's potential role in hepatic surgery.  相似文献   
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There have only been a few studies of chemo-endocrine therapy compared with endocrine therapy alone in newly diagnosed prostate cancer patients. We assessed the effects of these two therapies by comparing long-term survival rates. One hundred and twenty-nine patients were entered in this study between November 1977 and March 1992. Seventy-seven patients were treated with endocrine therapy alone. Other 52 patients received chemo-endocrine therapy, which included orchiectomy and/or diethylstilbestrol diphosphate (DES-DP) plus Cisplatin, with or without other cytotoxic agents. All patients had bone metastasis at the beginning of the study. There was a significant difference in survival between patients who received endocrine therapy and chemo-endocrine therapy (P = 0.0078). That is, survival rate was superior for the chemoendocrine therapy patients throughout the entire follow-up period. These data suggest that early chemo-endocrine therapy containing Cisplatin, with or without maintenance chemotherapy, is a potentially effective treatment for newly diagnosed metastatic prostate cancer and is worth further investigation via a randomized trial.  相似文献   
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Optimal initial palliation and a subsequent staged approach is mandatory for high-risk Fontan candidates. We describe the case of mitral atresia with severe tricuspid regurgitation and pulmonary hypertension successfully managed by repeated palliation from the neonatal period and 2-stage Fontan surgery. A 1-month-old boy diagnosed with mitral atresia and double-outlet right ventricle underwent pulmonary artery banding at 1 month of age, followed by repeated pulmonary artery banding accompanied by tricuspid annuloplasty and atrial septal defect enlargement at 6 months. Because of the presence of pulmonary artery distortion, right ventricular dysfunction, and borderline pulmonary vascular resistance, a hemi-Fontan procedure was conducted with extended pulmonary artery plasty when the boy was 3 years and 8 months old. Cardiac catheterization done 3 months after showed improvement in risk factors, and the final Fontan operation (total cavopulmonary connection) was successfully done in conjunction with repeated tricuspid annuloplasty when the boy was 4 years and 5 months old. The patient remains in excellent clinical condition at the last follow-up 5 years after the final Fontan procedure with sinus rhythm and good ventricular function.  相似文献   
16.
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.  相似文献   
17.
Kaneo  Yoshiharu  Fujihara  Yumie  Tanaka  Tetsuro  Kozawa  Yoko  Mori  Hideki  Iguchi  Sadao 《Pharmaceutical research》1989,6(12):1025-1031
Glutathione was covalently attached to dextran (T-40) by the CNBr activation method. The compound obtained was a water-soluble powder containing 10 (w/w%) glutathione, which was gradually released from the conjugate in aqueous media. Mice depleted of glutathione by treatment with buthionine sulfoximine, a potent inhibitor of -glutamylcysteine synthetase, exhibited a significant increase in hepatic glutathione level after intravenous injection of the conjugate. In mice given a lethal dose of acetaminophen, the survival rate increased progressively with coadministration of the conjugate, whereas little improvement was found when free glutathione was given. The conjugate maintained the serum transaminase activities at lower level after acetaminophen administration. These findings suggest that the dextran conjugate of glutathione is transported into hepatic cells and is intracellulary hydrolyzed to free form, which protects mice from hepatotoxicity due to acetaminophen.  相似文献   
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We investigated the effects of erythropoietin (Epo) in glial cell development, especially the maturation of late stage immature oligodendrocytes and the proliferation of astrocytes. Epo mRNA level in oligodendrocytes was much more prominent than those in neurons or astrocytes, which were the same as those in the young adult kidney, while Epo receptor (Epo-R) mRNA level were almost the same among neural cells, kidney and liver tissues. On immunohistochemical examination, Epo-R expression was also detected in O4-positive immature oligodendrocytes and glial fibrillary acidic protein positive astrocytes. These results suggested that types of both glial cells are responsive to Epo. The numbers of mature oligodendrocytes, which are characterized by myelin basic protein and process development, were increased by treatment with recombinant human Epo (rhEpo) (0.001-0.1 U/ml). The maturation of oligodendrocytes was also enhanced by coculture with astrocytes in vitro. However, when mixed cultured cells (oligodendrocytes+astrocytes) were treated with anti-Epo antibody and/or soluble Epo-R, the differentiation of oligodendrocytes was partially inhibited. Interestingly, high dose rhEpo (1, 3, 10 U/ml) markedly enhanced the proliferation of astrocytes. These results suggested that Epo not only promotes the differentiation and/or maturation in oligodendrocytes, but also enhances the proliferation of astrocytes. It is generally accepted that astrocytes produce Epo, and therefore Epo might act on astrocytes in an autocrine manner. The astrocytes stimulated with Epo may further accelerate the maturation of oligodendrocytes. These comprehensive effects of Epo might also affect the ability of oligodendrocyte lineage cells to promote myelin repair in the normal and damaged adult central nervous system.  相似文献   
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