Early release of cytochrome C and activation of caspase-3 in hyperglycemic rats subjected to transient forebrain ischemia

The mechanisms underlying the aggravating effect of hyperglycemia on brain damage are still elusive. The present study was designed to test our hypothesis that hyperglycemia-mediated damage is caused by mitochondrial dysfunction with mitochondrial release of cytochrome c (cyt c) to the cytoplasm, which leads to activation of caspase-3, the executioner of cell death. We induced 15 min of forebrain ischemia, followed by 0.5, 1, and 3 h of recirculation in sham, normoglycemic and hyperglycemic rats. Release of cyt c was observed in the neocortex and CA3 in hyperglycemic rats after only 0.5 h of reperfusion, when no obvious neuronal damage was observed. The release of cyt c persisted after 1 and 3 h of reperfusion. Activation of caspase-3 was observed after 1 and 3 h of recovery in hyperglycemic animals. No cyt c release or caspase-3 activation was observed in sham-operated controls while a mild increase of cyt c was observed in normoglycemic ischemic animals after 1 and 3 h of reperfusion. The findings that there is caspase activation and cyt c relocation support a notion that the biochemical changes that constitute programmed cell death occur after ischemia and contribute, at least in part, to hyperglycemia-aggravated ischemic neuronal death.

[Construction of linkage map and mapping resistance gene of Scterotinia scterotiorum in Brassica napus]

Scterotinia scterotiorum (Lib.) de by is a world-wide disease, which seriously decreases the yield and the quality of oil of rapeseed. Mapping resistance genes of S. scterotiorum is of vital effect to breed new elite cultivars resisting the disease. In this paper, we reported that a RAPD linkage map was constructed, including 193 RAPD markers, 19 linkage groups and covering 1,324 cM, by using Mapmaker 3.0. On the basis of map, and resistance genes, Sc1, Sc2 and Sc3, were located in 4th, 8th and 18th linkage groups. Among three QTLs, Sc2 has the characteristics of major gene with explained 29%. The three QTLs together explained about 56% of phenotypic variation.

Increased expression of iNOS and c-fos via regulation of protein tyrosine phosphorylation and MEK1/ERK2 proteins in terminal bronchiole lesions in the lungs of rats exposed to cigarette smoke

Epidemiological evidence suggests that smoking is a major cause of human lung cancer. However, the mechanism by which cigarette smoke induces the cancer remains unestablished. To evaluate the effects of cigarette smoke on the expression of inducible nitric oxide synthase (iNOS), nuclear protooncogenes and related mitogen-activated protein kinases (MAPKs) in rat lung tissue, a histopathological study of the effects of gas-phase cigarette smoke on rat lung tissue were carried out. The terminal bronchioles were found to be infiltrated predominantly by lymphocytes in the peribronchiolar region and a mild to moderate degree of emphysema was noted in the alveolar spaces. The terminal bronchioles also showed marked lipid peroxidation, dilatation, and peribronchiolar fibrosis. Immunohistochemical evaluation showed that the expression of iNOS, NF-kappa B, MAPKs (MEK1, ERK2), phosphotyrosine protein and c-fos was increased in the terminal bronchioles but protein kinase C (PKC), MEKK-1, c-jun, p38 and c-myc showed no change. These results provide evidence to suggest that exposure to cigarette smoke results in oxidant stress which leads to the stimulation of iNOS and c-fos together with the induction of protein tyrosine phosphorylation and MEK1/ERK2 which in turn may promote lung pathogenesis.

Liver transplantation in Asian patients with chronic hepatitis B using lamivudine prophylaxis

OBJECTIVE

To report the results of liver transplantation in 31 Asian patients with chronic hepatitis B using lamivudine prophylaxis in an open-label study.

SUMMARY BACKGROUND DATA

Chronic hepatitis B is a prevalent cause of end-stage liver disease in Asia, but the results of liver transplantation in these patients are poor.

METHODS

Thirty-one Asian patients with chronic hepatitis B underwent liver transplantation using lamivudine prophylaxis (100 mg daily). Twenty-three (74%) patients had detectable serum hepatitis B envelope antigen (n = 18) or hepatitis B virus DNA (n = 11) before treatment, and seven had associated hepatocellular carcinoma. Lamivudine was continued indefinitely after transplantation, and hepatitis B immune globulin was not used.

RESULTS

The actuarial patient and graft survival rates were 84% and 81%, respectively. Five patients died of causes unrelated to hepatitis B, and 26 patients were alive at a median follow-up of 16 months (range 6-47) after transplantation. One (3.8%) patient developed recurrent hepatitis B resulting from viral breakthrough at week 53 and survived after retransplantation using adefovir and hepatitis B immune globulin treatment. The remaining 25 surviving patients had no biochemical or histologic evidence of recurrent hepatitis, and serum hepatitis B virus DNA remained negative by polymerase chain reaction. In six patients, hepatitis B surface antigen (HBsAg) persisted or reappeared in serum. Among 19 patients who became negative for HBsAg from 5 to 431 days after transplantation, 13 developed anti-HBsAb that lasted a median of 6 months (range 1-21). None of the seven patients with hepatocellular carcinoma developed recurrent tumor.

CONCLUSIONS

Asian patients with chronic hepatitis B may achieve a good outcome after liver transplantation using lamivudine prophylaxis.

Management of gallstone cholangitis in the era of laparoscopic cholecystectomy

HYPOTHESIS

The combined endoscopic and laparoscopic approach is safe and effective in managing gallstone cholangitis in the era of laparoscopic cholecystectomy (LC).

DESIGN

Retrospective case series.

SETTING

University teaching hospital.

PATIENTS

One hundred eighty-four consecutive patients with gallstone cholangitis treated between January 1995 and December 1998.

INTERVENTIONS

The main treatments were endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (ES) followed by interval LC. Open or laparoscopic common bile duct exploration (OCBDE or LCBDE) was used when ERCP or ES failed.

MAIN OUTCOME MEASURES

Success of various interventions, morbidity and mortality, and long-term incidence of recurrent biliary symptoms.

RESULTS

Endoscopic retrograde cholangiopancreatography was successful in 175 patients (95%), with bile duct stones found in 147 (84%). Endoscopic stone clearance by ES was achieved in 132 patients (90%). Morbidity rate after ERCP or ES was 4.0% (n = 7), and overall mortality rate from cholangitis was 1.6% (n = 3). After bile duct stone clearance, 82 patients underwent LC with a conversion rate of 9.8% (n = 8) and a morbidity rate of 3.6% (n = 3). Eighteen patients underwent OCBDE with a morbidity rate of 33% (n = 6), and 3 underwent LCBDE with 1 conversion and no morbidity. There was no operative mortality. Seventy-eight patients were managed conservatively after endoscopic clearance of bile duct stones. Follow-up data were available in 101 patients with cholecystectomy and 73 patients with gallbladder in situ. During a median follow-up of 24 months, recurrent biliary symptoms occurred in 5.9% (n = 6) and 25% (n = 18), respectively (P =.001). In both groups, the most common recurrent symptom was cholangitis (n = 5 and n = 14, respectively). Gallbladder in situ (risk ratio, 4.16; 95% confidence interval, 1.39-12.50; P =.01) and small-size papillotomy (risk ratio, 2.94; 95% confidence interval, 1. 07-8.10; P =.04) were significant risk factors for recurrent biliary symptoms.

CONCLUSIONS

Endoscopic sphincterotomy for biliary drainage and stone removal, followed by interval LC, is a safe and effective approach for managing gallstone cholangitis. Patients with gallbladder left in situ after ES have an increased risk of recurrent biliary symptoms. Laparoscopic cholecystectomy should be recommended after endoscopic management of cholangitis except in patients with prohibitive surgical risk.33333333333333333333333

Determining resectability for hepatocellular carcinoma: the role of laparoscopy and laparoscopic ultrasonography

We reviewed our experience with preoperative determination of resectability in patients with hepatocel-lular carcinoma (HCC) over the last 10 years, and evaluated the role of laparoscopy with laparoscopic ultrasonography (USG) since we instituted this technique in June 1994. From January 1989 to December 1998, 500 of 1741 patients with HCC (28.7%) were considered suitable for hepatic resection after preoperative assessment. Significantly more contrast-enhanced computed tomography (CT) scans and fewer percutaneous USGs or hepatic arteriograms were performed in the 299 patients managed since June 1994 (group 2) than in the 201 patients managed before then (group 1). One hundred and ninety-eight patients in group 2 (66%) underwent laparoscopy with laparoscopic USG. Unresectable disease was found in 41 patients in group 1 (20.4%) (all at laparotomy), and in 68 patients in group 2 (22.7%) (16 at laparotomy without laparoscopic examination, 31 at laparoscopic examination alone, and 21 at laparotomy after an inconclusive laparoscopic examination) (P = 0.5). The most common features of unresectable disease were the presence of bilobar intrahepatic metastases and an inadequate liver remnant with cirrhosis. The adoption of the laparoscopic examination after June 1994 improved the overall resection rate at laparotomy in group 2 from 77.3% to 86. 2%, which was better than that in group 1 (79.6%, P = 0.057). For patients with unresectable disease, the operation time and hospital stay were significantly shorter in group 2. The postoperative morbidity and mortality rates were 9.8% and 4.9%, respectively, in group 1, and 5.9% and 2.9% in group 2. There was no operative morbidity in the 31 patients who had unresectable disease detected by the laparoscopic examination alone. Laparoscopy with laparoscopic USG avoids unnecessary laparotomy, and has a definite role in determining resectability in patients with HCC.

[The development of a static water/gas separator]

Objective. To develop a device for separating water from gas in small flow rate under zero "G". Method. Beginning with the study of surface characteristic of materials, a capillary material was developed according to the requirement and the water/gas separator using this single separating material was designed. Result. The water/gas separator worked well in the range of gas flow below 10.0 L/min and water flow below 10.0 ml/min. No gas was found in the separated water and no water was found in the separated gas. Conclusion. The structure of the separator was reasonable and the water/gas separating method using a single separating material was feasible.

Inhibitory effect of esculetin on oxidative damage induced by t-butyl hydroperoxide in rat liver

Increasing evidence regarding free radical-generating agents and inflammatory processes suggests that accumulation of reactive oxygen species can cause hepatotoxicity. A short-chain analog of lipid hydroperoxide, t-butyl hydroperoxide (t-BHP), can be metabolized to free radical intermediates by cytochrome P-450 in hepatocytes, which in turn can initiate lipid peroxidation, affect cell integrity and result in cell injury. In this study, we used t-BHP to induce hepatotoxicity in vitro and in vivo and determined the antioxidative bioactivity of esculetin, a coumarin compound. Our investigations showed that pretreatment with esculetin (5-20 microg/ml) significantly decreased the leakage of lactate dehydrogenase (LDH) and alanine transaminase (ALT), and also decreased the formation of malondialdehyde (MDA) in primary cultured rat hepatocytes induced by a 30-min treatment with t-BHP. An in vivo study in rats showed that pretreatment with esculetin (i.p.) at concentrations of 0.5 and 5 mg/kg for 5 days before a single i.p. dose of t-BHP (0.1 mmol/kg) significantly lowered the serum levels of the hepatic enzyme markers (ALT and AST) and reduced oxidative stress in the liver. Histopathological evaluation of the rat livers revealed that esculetin reduced the incidence of liver lesions induced by t-BHP, including hepatocyte swelling, leukocyte infiltration, and necrosis. Based on the results described above, we speculate that esculetin may play a chemopreventive role via reducing oxidative stress in living systems.

Involvement of caspase-3 in cell death after hypoxia-ischemia declines during brain maturation

The involvement of caspase-3 in cell death after hypoxia-ischemia (HI) was studied during brain maturation. Unilateral HI was produced in rats at postnatal day 7 (P7), 15 (P15), 26 (P26), and 60 (P60) by a combination of left carotid artery ligation and systemic hypoxia (8% O2). Activation of caspase-3 and cell death was examined in situ by high-resolution confocal microscopy with anti-active caspase-3 antibody and propidium iodide and by biochemical analysis. The active caspase-3 positive neurons were composed of more than 90% HI damaged striatal and neocortical neurons in P7 pups, but that number was reduced to approximately 65% in striatum and 34% in the neocortex of P15 pups, and approximately 26% in striatum and 2% in neocortex of P26 rats. In P60 rats, less than 4% of the damaged neurons in striatum and less than 1% in neocortex were positive for active caspase-3. Western blot analysis demonstrated that the level of inactive caspase-3 in normal forebrain tissue gradually declined from a high level in young pups to very low levels in adult rats. Concomitantly, HI-induced active caspase-3 was reduced from a relatively high level in P7, to moderate levels in P15 and P26, to a barely detectable level in P60 rats. The authors conclude that the involvement of caspase-3 in the pathogenesis of cell death after HI declines during neuronal maturation. The authors hypothesize that caspase-3 may play a major role in cell death in immature neurons but a minor role in cell death in mature neurons after brain injury.

Different risk factors and prognosis for early and late intrahepatic recurrence after resection of hepatocellular carcinoma

BACKGROUND

Recent studies have shown that the prognosis of recurrent hepatocellular carcinoma (HCC) after resection was dependent on the time of recurrence. The current study investigated whether early and late intrahepatic recurrences were associated with different risk factors and prognostic factors.

METHODS

After curative resection of HCC, 246 patients were followed prospectively for recurrence. Intrahepatic recurrences were classified into early (</= 1 year) and late (> 1 year) recurrences. Risk factors for recurrence and prognostic factors for survival after recurrence in each group were analyzed.

RESULTS

Early and late intrahepatic recurrences developed in 80 patients and 46 patients, respectively. By multivariate analysis, preoperative tumor rupture (P = 0.022) and venous invasion (P < 0.001) were independent risk factors for early recurrence, whereas cirrhosis (P = 0.018) was the only significant risk factor for late recurrence. By comparing histologic features of resected recurrent and primary tumors, 8 of 9 resected early recurrent tumors (89%) were classified as intrahepatic metastases, whereas all 6 resected late recurrent tumors (100%) were multicentric occurrences. Despite similar treatments, the prognosis for patients with early recurrence was worse than that of patients with late recurrence (median survival of 15.8 months vs. 29.6 months; P = 0.005). Independent prognostic factors for early recurrence were serum albumin level and initial tumor pTNM classification, whereas only serum bilirubin level was found to be an independent prognostic factor for late recurrence.

CONCLUSIONS

Early and late intrahepatic recurrences after resection of HCC were associated with different risk factors and prognostic factors. Early recurrences appear to arise mainly from intrahepatic metastases, whereas late recurrences are more likely to be multicentric in origin. The current study suggests that different strategies may be needed for the prevention and management of early and late recurrences. Further studies based on genetic analysis of clonal origins of tumors are required to clarify fully the mechanism of early and late recurrences after resection of HCC.

Different risk factors and prognosis for early and late intrahepatic recurrence after resection of hepatocellular carcinoma

BACKGROUND

Recent studies have shown that the prognosis of recurrent hepatocellular carcinoma (HCC) after resection was dependent on the time of recurrence. The current study investigated whether early and late intrahepatic recurrences were associated with different risk factors and prognostic factors.

METHODS

After curative resection of HCC, 246 patients were followed prospectively for recurrence. Intrahepatic recurrences were classified into early (</= 1 year) and late (> 1 year) recurrences. Risk factors for recurrence and prognostic factors for survival after recurrence in each group were analyzed.

RESULTS

Early and late intrahepatic recurrences developed in 80 patients and 46 patients, respectively. By multivariate analysis, preoperative tumor rupture (P = 0.022) and venous invasion (P < 0.001) were independent risk factors for early recurrence, whereas cirrhosis (P = 0.018) was the only significant risk factor for late recurrence. By comparing histologic features of resected recurrent and primary tumors, 8 of 9 resected early recurrent tumors (89%) were classified as intrahepatic metastases, whereas all 6 resected late recurrent tumors (100%) were multicentric occurrences. Despite similar treatments, the prognosis for patients with early recurrence was worse than that of patients with late recurrence (median survival of 15.8 months vs. 29.6 months; P = 0.005). Independent prognostic factors for early recurrence were serum albumin level and initial tumor pTNM classification, whereas only serum bilirubin level was found to be an independent prognostic factor for late recurrence.

CONCLUSIONS

Early and late intrahepatic recurrences after resection of HCC were associated with different risk factors and prognostic factors. Early recurrences appear to arise mainly from intrahepatic metastases, whereas late recurrences are more likely to be multicentric in origin. The current study suggests that different strategies may be needed for the prevention and management of early and late recurrences. Further studies based on genetic analysis of clonal origins of tumors are required to clarify fully the mechanism of early and late recurrences after resection of HCC.

[Design of reaction canister in a solid amine carbon dioxide removal system]

Objective. To design a reaction canister using in solid amine carbon dioxide removal system for long-duration spaceflight. Method. On consideration of system demand and properties of solid amine, key problems must be solved were found out: 1) the rated resistance limit tends to shorten the length of the canister while absorption and concentration require to increase the length of the canister; 2) limited quantity of heat for keeping the temperature of the canister; 3) inflation or contraction of the solid amine under micro-gravity. Result. After appropriate measures were taken, effective adsorption and desorption, as well as concentration of CO2 were achieved, the concentration of CO2 in the space cabin could be controlled below 0.5%; and the concentration of the concentrated CO2 was as high as 98% so that it could be directly send to the CO2 reduction system; and that the resistance of the canister was below 160 mm H2O; moreover, the energy consumption was decreased to below 650 W. Conclusion. The designed reaction canister could meet the requirements of the solid amine carbon dioxide (correction of bioxide) removal system under microgravity.

Alteration of MAP kinase pathways after transient forebrain ischemia

Extracellular regulated kinase (ERK) transduce growth factor signals while c-Jun NH(2)-terminal kinase (JNK) delivers stress signals into the nuclei for regulation of gene expression. These signaling pathways were studied by laser-scanning confocal microcopy and Western blot analysis using phospho-specific antibodies on rat brains that were subjected to 15 minutes transient forebrain ischemia followed by varied periods of reperfusion. Extracellular regulated kinase was activated at 30 minutes and 4 hours of reperfusion in the nuclei and dendrites of surviving dentate gyrus (DG) cells, but not in dying CA1 neurons after ischemia. Tyrosine phosphorylation of Trk kinase, an ERK upstream growth factor receptor, was elevated in the DG tissue, and to a lesser extent in the CA1 region. In addition, phosphorylation of activating transcription factor-2 (ATF-2) and c-Jun was selectively increased in CA1 dying neurons during the late period of reperfusion. These findings suggested that the Trk-ERK signaling pathway might be neuroprotective for dentate granule cells. The activation of ATF-2 and c-Jun pathways in the late period of reperfusion in CA1 dying neurons might reflect damage signals in these neurons. These results suggested that the lack of protective signals acting in concert with the presence of damage signals in CA1 neurons after ischemia might contribute to delayed neuronal death after transient forebrain ischemia.

Anterior approach for major right hepatic resection for large hepatocellular carcinoma

OBJECTIVE

To report the surgical and long-term outcomes of major right hepatic resection for large hepatocellular carcinoma (HCC) using the anterior approach compared with the conventional approach.

SUMMARY BACKGROUND DATA

Great difficulty can be encountered during major right hepatic resection for large HCC using the conventional approach. Forceful retraction during mobilization of the tumor might result in serious complications, including dissemination of cancer cells, iatrogenic tumor rupture, and excessive bleeding, leading to unfavorable surgical and long-term outcomes.

METHODS

In patients who had large HCC at the right lobe of liver and underwent major hepatic resection, the technique of anterior approach was used. After hilar control of the inflow blood vessels and without prior mobilization of the right lobe of liver and the tumor, parenchymal transection was performed using an ultrasonic dissector from the anterior surface of the liver until the anterior surface of the inferior vena cava was exposed. All venous tributaries, including the right hepatic vein, were controlled before the right lobe of liver was mobilized. Surgical and long-term outcomes were analyzed retrospectively and compared with patients who underwent surgery using the conventional approach.

RESULTS

From 1989 to 1997, the anterior approach was used for major right hepatic resection in 54 patients with HCC of 5 cm or more in diameter. When compared with the 106 patients with similar clinical parameters who underwent hepatic resection using the conventional approach during the same period, the patients in the anterior approach group had significantly less intraoperative blood loss and blood transfusion, a lower hospital death rate, a lower incidence of pulmonary metastases, and a better median disease-free survival and median overall cumulative survival.

CONCLUSION

The anterior approach is the preferred technique for major right hepatic resection for large HCC because it resulted in improved surgical and survival outcomes compared with the conventional approach.

Crystallization of agglutinin from the seeds of Abrus precatorius

Agglutinin protein purified from the seeds of Abrus precatorius has a high antitumour activity and was crystallized at room temperature with polyethylene glycol 8000 as the precipitant. The agglutinin crystal diffracted to 3.45 A and belongs to one of two possible tetragonal space groups, P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 141.91, c = 105.63 A. The asymmetric unit contains a heterotetrameric protein molecule of molecular weight 134 kDa and has a solvent content of approximately 38%.

Tacrolimus (FK 506) induced thrombotic thrombocytopenic purpura after ABO mismatched second liver transplantation: salvage with plasmapheresis and prostacyclin

We report the course of thrombotic thrombocytopenic purpura (TTP) in a patient receiving tacrolimus (FK506) immunosuppression for an ABO mismatched second liver graft. A Chinese woman with fulminant hepatitis-B reactivation failed a living-related orthotopic liver transplantation (OLT) due to portal vein thrombosis. An ABO mismatched cadaveric OLT (group A to O) was performed, with peri-operative plasmapheresis to reduce anti-A hemagglutinin titers. On day 30, she developed fever, hemolysis, thrombocytopenia and neurologic dulling. Prominent microangiopathic features in peripheral blood film, and characteristic brain lesions on magnetic resonance imaging confirmed TTP. She responded initially to intensive plasmapheresis with cryosupernatant replacement, and withdrawal of FK506. An attempted reintroduction of FK506 for threatened rejection led to TTP exacerbation. This was controlled with prolonged plasmapheresis and a ten-day infusion of prostacyclin. Immunosuppression was changed to mycophenolate mofetil. By day 53, the peripheral film and lactate dehydrogenase level had returned to baseline and plasmapheresis was stopped.

[The study on CO2 concentration in solid amine CO2 control system]

OBJECTIVE

To solve the problem of CO2 concentration and collection in solid amine CO2 control system for long-duration spacecraft cabin.

METHOD

One approach was presented on the base of the principle of absorption and desorption, and was then tested by the apparatus according to it.

RESULT

The average concentration of the concentrated CO2 was as high as 95%, which can be directly sent to the CO2 reduction system, and about 90% of the concentrated CO2 can be collected.

CONCLUSION

The designed apparatus met the requirements of the CO2 reduction system.

Esophageal carcinoma in a patient with bleeding esophageal varices

More than 20 cases of esophageal carcinoma have been reported to develop after endoscopic injection sclerotherapy (EIS), and this technique is implicated in the pathogenesis of esophageal cancer. We report a case of esophageal carcinoma presenting as a superficial ulcer in a patient with esophageal varices with no prior EIS. Whether the development of esophageal carcinoma in patients with previous EIS is coincidental or consequential is controversial. Such carcinoma might have already existed before EIS in some reported cases. A causal relationship between EIS and esophageal carcinoma cannot be established without further clarification by a well-designed study.

Intracerebral hemorrhage after liver transplantation

We report 5 patients with intracerebral hemorrhage after orthotopic liver transplantation (OLT) and identify the possible risk factors. Between November 1991 and April 1999, 75 adult patients received 77 orthotopic liver transplants at Queen Mary Hospital, Hong Kong. Five patients (6.5%) developed intracerebral hemorrhage postoperatively. Clinical and laboratory data were reviewed, and potential risk factors were analyzed. The 5 patients developed intracerebral hemorrhage within 40 days (range, 1 to 37 days; median, 4 days) after OLT. The mortality rate was 80% (4 of 5 patients). The intraoperative blood transfusion volume (median, 17,200 mL; range, 15,750 to 30,360 mL) administered to patients who developed intracerebral hemorrhage postoperatively was significantly greater than that (median, 6,990 mL; range, 1,840 to 22,680 mL) for patients without the complication (P =.0008). Massive intraoperative transfusion (>15,000 mL) was required in all 5 patients (100%) with intracerebral hemorrhage but only 9 of 72 patients (12.5%) in the other group (P =.0001). Four of 5 patients (80%) with intracerebral hemorrhage had intraoperative hypotension compared with 7 of 72 patients (9.7%) in the other group (P =.001). No significant difference was found in age, prothrombin time (PT), activated partial thromboplastin time (APTT), incidence of hypertension, bleeding at extracerebral sites, cyclosporine A neurotoxicity, thrombocytopenia, hemodialysis, and sepsis between the patients with and without intracerebral bleeding. However, the median cumulative score of coagulation parameters (PT, APTT, platelet count) was significantly greater in the group with than without intracerebral bleeding (median score, 3 v 1; P =.023). Intracerebral hemorrhage is 1 of the most disastrous complications after OLT. Intraoperative hypotension, massive intraoperative transfusion, and coagulopathy may be correlated with this complication.

Protein aggregation after transient cerebral ischemia

Protein aggregates containing ubiquitinated proteins are commonly present in neurodegenerative disorders and have been considered to cause neuronal degeneration. Here, we report that transient cerebral ischemia caused severe protein aggregation in hippocampal CA1 neurons. By using ethanolic phosphotungstic acid electron microscopy (EM) and ubiquitin immunogold EM, we found that protein aggregates were accumulated in CA1 neurons destined to die 72 hr after 15 min of cerebral ischemia. Protein aggregates appeared as clumps of electron-dense materials that stained heavily for ubiquitin and were associated with various intracellular membranous structures. The protein aggregates appeared at 4 hr and progressively accumulated at 24 and 48 hr of reperfusion in CA1 dying neurons. However, they were rarely observed in dentate gyrus neurons that were resistant to ischemia. At 4 hr of reperfusion, protein aggregates were mainly associated with intracellular vesicles in the soma and dendrites, and the nuclear membrane. By 24 hr of reperfusion, the aggregates were also associated with mitochondria, the Golgi apparatus, and the dendritic plasmalemma. High-resolution confocal microscopy further demonstrated that protein aggregates containing ubiquitin were persistently and progressively accumulated in all CA1 dying neurons but not in neuronal populations that survive in this model. We conclude that proteins are severely aggregated in hippocampal neurons vulnerable to transient brain ischemia. We hypothesize that the accumulation of protein aggregates cause ischemic neuronal death.