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Biomedical subjects

Y Kurumi

Publications and source records attributed to Y Kurumi.

At least 19 recordsLinked to original sources
PubMed2001

Bile salt tauroursodeoxycholic acid modulation of Bax translocation to mitochondria protects the liver from warm ischemia-reperfusion injury in the rat.

BACKGROUND: Tauroursodeoxycholic acid (TUDC) is a hydrophilic bile acid that has a cytoprotective effect in primary biliary cirrhosis and primary sclerosing cholangitis. TUDC also protects hepatocytes from hydrophobic bile acid-induced apoptosis. The aim of this study was to determine whether TUDC ameliorates hepatocyte apoptosis during ischemia-reperfusion injury. METHODS: We used a rat model of hepatic warm ischemia-reperfusion injury to assess the effects of TUDC. Male Sprague-Dawley rats were subjected to 1 or 2 hr of normothermic ischemia followed by 3 or 6 hr of reperfusion. The treatment group received TUDC (50 mg/kg) by bolus intravenous injection 30 min before initiation of ischemia, whereas the control group received saline only. Blood samples for biochemical analysis were obtained after 6 hr of reperfusion. Liver biopsies for histological assessment were obtained 3 and 6 hr after reperfusion. Hepatocyte apoptosis was determined by terminal dUTP nick-end labeling. The pro-apoptotic protein Bax was quantified at the mRNA and protein level. RESULTS: Treatment with TUDC significantly reduced serum transaminase levels. This was associated with a significant amelioration in the levels of hepatocyte apoptosis in the TUDC-treated group compared with control. Furthermore, Western blot analysis of Bax expression in liver tissue indicated that TUDC inhibited the translocation of Bax from the cytosol to the mitochondria. CONCLUSIONS: TUDC significantly reduced hepatic injury in this model. The beneficial effects of TUDC upon hepatocyte apoptosis were related to the modulation of Bax protein translocation.

Animals↗
PubMed2001

Cellular distribution of thrombomodulin as an early marker for warm ischemic liver injury in porcine liver transplantation: protective effect of prostaglandin I2 analogue and tauroursodeoxycholic acid.

BACKGROUND: Warm ischemia of the graft from non-heart-beating donors is considered a risk factor for posttransplant graft dysfunction. The early administration of cytoprotective agents may help improve graft dysfunction. METHODS: Four groups of 10 pigs each underwent orthotopic liver transplantation. Prostaglandin I2 analogue, OP-41483, was administered intraportally 30 min before warm ischemic insult in donors and after reperfusion in recipients in one group. In the other study group, additional intravenous tauroursodeoxycholic acid (TUDC) was given before the warm ischemic insult in donors and after reperfusion, then maintained continuously until postoperative day (POD) 7. RESULTS: Exposure of liver grafts to warm ischemia resulted in severe congestion with the disappearance of thrombomodulin (Tm) from the sinusoidal endothelial cells (SECs) and smooth muscle cells (SMCs) around biliary epithelial cells (BEpCs) 2 hr after reperfusion, followed by positive immunoreactivity of Tm in BEpCs with hyperbilirubinemia, which was related to high mortality. Combined administration of OP-41483 and TUDC had a protective effect, demonstrated by sustained immunoreactivity of Tm from SECs and SMCs until POD 7, without that reactivity in BEpCs. This was associated with reduced congestion and hyperbilirubinemia, similar to the control group not subjected to warm ischemia. CONCLUSIONS: These findings suggest that negative immunoreactivity of Tm in SECs and SMCs surrounding BEpCs and positive in BEpCs may be an early marker for ischemic liver injury, and that OP-41483 and TUDC may protect against the microcirculatory and biliary derangement.

Animals↗
PubMed2001

[Tumor ablation with MRI navigation--a novel method of microwave coagulation therapy for hepatic tumor].

Fifty-eight patients with hepatic tumor which consisted of 22 hepatocellular carcinomas and 36 metastatic liver tumors were treated by microwave coagulation therapy with MRI navigation. The tumors were located in all segments of liver except S1. In 24 cases among them, the abdominal approach was difficult, because the tumors were located just below the diaphragm. These cases were selected for thoracoscope-assisted microwave ablation under MR-guidance across the diaphragm. All MR data were collected on a vertically oriented open MRI system (0.5 T SIGNA SP/i system: GE Medical Systems). The microwave electrode was introduced into the liver through a 14G needle via a percutaneous puncture with real-time MR image navigation. Microwave ablations at 60 W for 60 seconds were repeated several times depending on the tumor size. MR imaging may be employed as a reliable guide for percutaneous puncture. Moreover, sufficient safety margin could be obtained for hepatic tumor ablation. MR-guided microwave thermoablation therapy is a feasible method of treatment for hepatic tumors.

Carcinoma, Hepatocellular↗
PubMed2000

The prevention of bile duct injury during laparoscopic cholecystectomy from the point of view of anatomic variation.

The aim of this study was to evaluate ways to prevent bile duct injury during laparoscopic cholecystectomy in patients with anomalous biliary tract anatomy. The biliary tract was studied using cholangiograms of 511 patients who had gallbladder disease and was dissected in 92 cadaveric specimens. The authors classified confluent forms of the cystic duct and the bile duct into five different types, including four anomalous types. Sixteen instances (3.13%) of anatomic variation of the biliary tract were found among the patients, and four cases (4.35%) were found in the cadavers. Among the 511 patients, there were 495 cases of type C anatomy, three cases of type A, seven cases of type R, six cases of type P, and zero cases of type L; among the 92 cadaveric specimens, there were 88 cases of type C anatomy, one case of type R, two cases of type P, and one case of type L. For anatomic types A, P, and R, there is a high probability of risk of cutting the wrong duct. Therefore, it is important to clarify the anatomy of the biliary tract by preoperative examination and to carefully dissect the cystic duct close to the neck of the gallbladder during laparoscopic cholecystectomy. Anatomic variation of the biliary tract is common and can create a rare pitfall during laparoscopic cholecystectomy.

Adolescent↗
PubMed1997

Bacterial translocation as a cause of septic shock in humans: a report of two cases.

While bacterial translocation has been reported to occur under numerous conditions in animal models, there has been no paper to date focusing on bacterial translocation as a direct cause of septic shock in humans. We present herein the cases of two patients who developed septic shock believed to have been directly caused by bacterial translocation. Neither of the patients had a focus of infection, the intestinal walls were intact in gross appearance, and the peritoneal cavity had not been contaminated by surgery. Moreover, in both patients, the same organisms were detected in the blood, ascites fluid, and mesenteric lymph nodes, and bacilli were found in the intestinal wall.

Aged↗
PubMed1997

Efficacy of prostaglandin I2 analog on liver grafts subjected to 30 minutes of warm ischemia.

Due to the fact that no effective conditioning agent for hemodynamically unstable donors exists, the number of suitable donors is limited. The efficacy of OP-41483, a stable analog of prostaglandin I2, as a conditioning agent of the liver was investigated in this study using pigs. OP-41483 was administered via the portal tributary for 10 min before 30 min of warm ischemia. Graft livers were procured after perfusion with OP-41483 in cold normal saline, then flushed with OP-41483 in Euro-Collins solution and placed in cold storage prior to orthotopic transplantation. OP-41483 was also administered intraportally for 120 min after reperfusion. Biochemical and histological studies, and survival rates were compared with a control group not given OP-41483 in an otherwise similar experimental protocol. The graft function recovered better in the OP group than in the control group, shown by the lactate values and lactate-to-pyruvate ratios. The marked congestion noted in the parenchyma of the control group livers was minimal in the OP group, verifying the microcirculatory effect of prostaglandin I2 by its vasodilatory and antithrombotic actions. These findings suggest that OP-41483 has some protective effect as a conditioning agent in liver transplantation, with timing of administration being crucial.

Alanine Transaminase↗
PubMed1997

Development of black gallstones after the nonsurgical management of splenic injury: report of a case.

A 22-year-old man was admitted to our Emergency Department after suffering splenic injury in a traffic accident. His intraabdominal bleeding was treated nonsurgically by the administration of total parenteral nutrition (TPN) and blood transfusions of packed red cells. He presented again 2 months after his discharge, being 3 months after the injury, for right hypochondralgia, at which time a gallstone was demonstrated on ultrasound (US) and computed tomography (CT). After endoscopic laparoscopic cholecystectomy, his symptoms disappeared and he has remained well since. The clinical course of this patient indicates that hemolytic hyperbilirubinemia can cause black gallstones as a late complication of the nonsurgical management of abdominal blunt trauma.

Abdominal Injuries↗
PubMed1997

Three-dimensional helical computed tomography with intravenous cholangiography for sclerosing cholangitis manifested as postcholecystectomy symptom.

A 46-year-old woman who had upper abdominal pain 10 years after cholecystectomy, and who had incidental sclerosing cholangitis (SC), was investigated by three-dimensional helical computed tomographic (3-DHCT) cholangiography with contrast medium, because endoscopic retrograde cholangiography (ERC) was unsuccessful and a second ERC was not permitted by the patient. The cholangiogram demonstrated annular strictures of the bilateral hepatic duct at the confluence of the common hepatic duct, and dilatation of the left intrahepatic biliary duct. Although we could not clarify the cause of the biliary tract deformity at the time of the 3-DHCT, the tentative diagnosis of postcholecystectomy deformity of the biliary tree led to successful treatment by right liver lobectomy and hepaticojejunostomy. Histologic findings were compatible with SC. From this experience and the literature, we suggest that 3-DHCT cholangiography with contrast medium can contribute to the preoperative diagnosis of morphological changes in the biliary tree in patients with postcholecystectomy symptoms.

Cholangiography↗
PubMed1995

Successful management of infantile hepatic hilar hemangioendothelioma with obstructive jaundice and consumption coagulopathy.

A 4-month-old boy with benign hemangioma of the porta hepatis is described. Obstructive jaundice and consumption coagulopathy developed, which were treated by percutaneous transhepatic drainage (PTHD), without resection of the tumor or bypass surgery. Because of tumor regression, the patient has remained free of symptoms even after the PTHD tube was removed. Because juvenile hemangioma is a benign tumor and occasional spontaneous regression is known to occur (as in our case and other reports), it is suggested that complete resection or bypass surgery is not necessary for juvenile hemangioendothelioma, even with obstructive jaundice, if bile drainage is adequately maintained.

Cholestasis↗
PubMed1993

[Prevention of postoperative recurrence after hepatic resection for metastatic colorectal cancer by adjuvant locoregional chemotherapy].

Postoperative adjuvant locoregional chemotherapy was performed on patients who underwent hepatic resection for metastatic colorectal cancer. To prevent recurrence in the residual liver after hepatic resection. 7 patients received intra-hepato-arterial infusion of MMC, 5-fluorouracil (5-FU), doxorubicin + Lipiodol emulsion. Sixteen cases did not receive such treatment. The 1-, 2- and 3-year cumulative disease free rates were 100, 80 and 40% in the patients with this adjuvant chemotherapy, against 61.4, 54.6 and 28.1% in those without this locoregional therapy, respectively. The 1-, 2- and 3-year cumulative survival rates were 100, 100 and 60% in the TAI-E group, and 73.7, 63.3 and 63.3% in the patients without TAI-E, respectively. Postoperative adjuvant locoregional chemotherapy is considered effective to prevent the recurrence of metastatic colorectal cancer in the residual liver after hepatectomy.

Aged↗
PubMed1993

[Evaluation of the combination of chemotherapy with etoposide, adriamycin and cisplatin (EAP) in advanced or recurrent gastric cancer].

EAP therapy was performed on 30 cases of advanced or recurrent gastric cancer between September 1987 and July 1991. The clinical responses of 15 trial patients were evaluated. The overall response rate was 40.0% (CR, one case; PR 5 cases). The results were thus not as favorable as that reported by Preusser et al. On the contrary, with such a poor response rate, this treatment did not lead to a prolonged life span (mean survival time; 5.6 months, median survival time; 4 months). Side effects, such as myelosuppression, appetite loss, nausea, vomiting, liver dysfunction, renal dysfunction, and alopecia, were also observed. Myelosuppression was a dose-limiting factor. The rhG-CSF proved in 4 cases to be a clinically useful tool against the neutropenia induced by this treatment. It may be concluded that EAP should be given to the following selected patients: (1) those whose condition is not so far advanced: (2) those who have not received many other forms of treatment; and (3) those in excellent general physical condition.

Adult↗
PubMed1991

Novel high-performance liquid chromatography for determination of membrane phospholipid composition of rat hepatocytes.

We have developed a new, quick and efficient method of high-performance liquid chromatography (HPLC) for the isolation and quantitative determination of phospholipids in hepatocyte membranes. A silica gel column was used for the isolation and determination, and an isocratic mixture of acetonitrile, methanol and 85% phosphoric acid (130:5:1.7, v/v/v) was used as a mobile phase. Six kinds of phospholipids, i.e. phosphatidylinositol (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and sphinogomyelin (SPH), in this order, were completely isolated within 45 min. The phospholipid composition of sinusoidal membrane vesicles (SMV) and canalicular membrane vesicles (CMV) obtained from rat liver, as well as of human erythrocyte ghosts were determined by this HPLC method. The level of SPH in CMV was significantly higher than that in SMV, and the level of PC in CMV was significantly lower than that in SMV. These results were considered attributable to the low fluidity of CMV. The phospholipid composition of human erythrocyte membrane was different from that of rat SMV and CMV. The present technique is suitable for quantitative determination of phospholipids in cell membranes.

Animals↗
PubMed1991

ATP-dependent taurocholate transport by rat liver canalicular membrane vesicles.

We conducted an experimental study to examine the possibility that ATP is involved in the mechanism by which bile acids are excreted through the liver canalicular membrane in opposing the concentration gradient. Canalicular membrane vesicles were purified from the livers of Sprague-Dawley rats, and the uptake of tritiated sodium taurocholate into canalicular membrane vesicles was determined by rapid filtration technique. Vesicle-associated sodium taurocholate was increased in the presence of ATP and ATP-regenerating system. This was also observed at a voltage-clamped condition. ATP-dependent uptake into the osmotically reactive intravesicular space was saturated with increasing concentrations of sodium taurocholate (Km = 47 mumol/L, Vmax = 270 pmoles/mg protein.20s). ATP-dependent uptake increased to the point of saturation when the sodium taurocholate concentration was 50 mumol/L and the ATP concentration was increased from 0 to 1 mmol/L (Km = 64 mumol/L). Among the several nucleotides used, ATP was a potent stimulator of transport, whereas a nonhydrolyzable analogue (i.e., adenosine 5'-[beta,gamma-imino]triphosphate) showed no effect. In addition, ATP-dependent transport was inhibited by vanadate in a dose-dependent manner. From these results it was concluded that the primary active transport of sodium taurocholate is present in hepatocellular canalicular membranes. This transport is directly dependent on ATP, and hydrolysis of gamma-phosphate of ATP is required.

Adenosine Triphosphate↗