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Y Shimahara

Publications and source records attributed to Y Shimahara.

At least 55 records · Page 3Linked to original sources
PubMed1995

[A case of bilateral multiple lung metastases from breast cancer successfully treated with carboplatin].

A 57-year-old female was admitted for right breast tumor. Modified radical mastectomy (Kodama method) was carried out. A prophylactic postoperative radiation was undertaken because of large tumor (T4b) and histologic metastasis to a Rotter's lymph node. At the end of irradiation, bilateral lung metastases were found on chest CT gram. The combination endocrine chemotherapy using MPA 600 mg and UFT 3 capsules p.o. daily and ADM 10 or 20 mg i.v. every two weeks was performed on an outpatient basis. As the lung metastases were increased four months later, carboplatin 150 mg i.v. was replaced with ADM. Four months later, the metastases almost disappeared on CT gram. These results suggested the possibility of one of the therapeutic options for metastatic breast cancer.

Adenocarcinoma↗
PubMed1994

Noninvasive evaluation of cytochrome c oxidase activity of the liver. Its prognostic value for hepatic resection.

OBJECTIVE: To clarify the relationship between the noninvasive evaluation of hepatic mitochondrial function, the redox tolerance test, and cytochrome c oxidase activity of the liver, focusing on surgical risk in hepatic resection. DESIGN: Six-month randomized clinical trial. SETTING: Inpatients in surgical department. STUDY PARTICIPANTS: Forty patients who underwent hepatic resection (n = 36) and other abdominal operations (n = 4). INTERVENTION: Preoperative, noninvasive: The redox tolerance test, which measures the changes in arterial ketone body ratio in response to 75 g of oral glucose loading. Intraoperative, invasive: Cytochrome c oxidase activity and energy charge of the liver. MAIN OUTCOME MEASURE: Correlation of the index in the redox tolerance test (RTI) with cytochrome c oxidase activity, both of which predict the postoperative course. RESULTS: The RTI values were negatively correlated with the maximal velocity (Vmax) and Michaelis constant (Km) values of cytochrome c oxidase activity. The maximal velocity and Michaelis constant values in patients with RTI values above or equal to 0.5 (group A, n = 29) were significantly lower than those in patients with RTI values below 0.5 (group B, n = 11). Eight (72.7%) of 11 patients in group B experienced postoperative complications. CONCLUSION: The RTI is a noninvasive method of assessing the hepatic energy metabolism and can be a useful index for evaluating surgical risk in hepatectomy.

Adenine Nucleotides↗
PubMed1994

Advantageous effect of low-molecular-weight heparin administration on hepatic mitochondrial redox state.

The effect of low-molecular-weight heparin (LMWH) on hepatic mithocondrial metabolism was compared with that of unfractionated heparin (UH) after the intravenous administration of these two kinds of heparin to normal rabbits. The magnitude of decrease in blood triglyceride levels 5 min after administration of UH (200 U/kg) was significantly greater than after LMWH (200 U/kg). Free fatty acid levels in the blood were significantly higher after this dose of UH than after LMWH. Blood total ketone body levels (acetoacetate + 3-hydroxybutyrate) 15 min after injection of 50 U/kg of UH were significantly higher than those after a dose of 50 U/kg of LMWH, and levels after 200 U/kg of UH were significantly higher than those after 200 U/kg of LMWH at 15, 30, 45 and 60 min. Enhanced ketogenesis was not noted after LMWH at any of the doses, or after UH at 3 U/kg. Arterial ketone body ratio (AKBR; acetoacetate/3-hydroxybutyrate), which reflects the hepatic mitochondrial oxidation-reduction state (NAD+/NADH), was maintained above 1.0 in all groups except in the U-200 group, while AKBR in that group was significantly decreased to 0.99 +/- 0.14 at 30 min, and further decreased to 0.80 +/- 0.08 at 60 min. These results indicate that LMWH has less effect on lipolysis than UH and does not enhance ketogenesis, resulting in less deterioration of mitochondrial redox state.

Animals↗
PubMed1993

Short-term changes in lipid and protein metabolism in liver transplants from living-related donors.

The effects of liver transplantation involving living-related donors were investigated in 20 pediatric cases in terms of protein and lipid metabolism using the extent of cholesterol esterification and the levels of total cholesterol, lecithine-cholesterol acyltransferase, apolipoprotein A-I, cholinesterase, and rapid turnover proteins as parameters. Cholesterol esterification increased from preoperative values of 39% +/- 4% to 67% +/- 1% (mean +/- SEM, n = 17) at 3 weeks after liver transplantation in successful cases but decreased from the preoperative value of 45% +/- 10% to 26% +/- 6% (n = 3) at 3 weeks in unsuccessful cases. Cholinesterase, transferrin, and prealbumin levels remained low after 3 weeks even in successful cases. Patients who had partial liver transplantations from living-related donors showed rapid recovery of cholesterol esterification. However, patients with graft livers required an extensive period before normalization of protein metabolism occurred, indicating the necessity for long-term follow-up of recipient development.

Adolescent↗
PubMed1993

Arterial ketone body ratio in pediatric liver transplantation.

Arterial ketone body ratio (AKBR) was measured serially in 49 pediatric orthotopic liver transplantations. The AKBR pattern correlated with hepatic synthetic function, as well as with short-term graft and patient survival. A rapid recovery pattern of AKBR to above 1.0 within 40 hr after reperfusion was associated with 94% graft and patient survival. Pediatric liver grafts were found to have better tolerance to low energy levels when compared with previously published data for adult OLT. The salvage rate of pediatric grafts exhibiting a slow recovery pattern (AKBR 0.7-1.0) was 71%. No recovery pattern (AKBR < 0.7) was seen in all 6 cases of primary nonfunction, and in 3 of 4 cases of early hepatic artery thrombosis (HAT). All these grafts were lost; however, 56% of the children in this group survived retransplantation. Unlike the PNF grafts, the no recovery pattern after HAT was characterized by gradual improvement of the synthetic function, despite the low energy state.

Arterial Occlusive Diseases↗
PubMed1993

Arterial ketone body ratio and glucose administration as an energy substrate in relation to changes in ketone body concentration after living-related liver transplantation in children.

Changes in the arterial ketone body ratio (AKBR [acetoacetate/3-hydroxybutyrate]), which reflect the redox state of the liver mitochondria (NAD+/NADH), as well as those in total ketone body concentration (TKB) and blood glucose level were studied in 30 living-related liver transplantations (LRLT) performed in pediatric patients at Kyoto University Hospital from June 1990 to January 1992. AKBR increased to over 1.0 within 6 hr after reperfusion of the graft in 11 cases (37%), within 12 hr in 7 (23%), on POD 1 in 8 (27%), and on POD 2 in the remaining 4 cases (13%). TKB significantly increased while AKBR remained below 0.7 (266 +/- 40 mumol/L), but it significantly decreased in accordance with the recovery of AKBR above 1.0 (61 +/- 6 mumol/L). This indicates the change in the predominant energy substrate for hepatic mitochondria from fatty acid to glucose during the AKBR recovery process. In 6 cases, the AKBR transiently decreased to below 1.0 after initial recovery concomitant with the fall in blood glucose level and the increase in TKB. However, the AKBR was rapidly restored to over 1.0 again immediately after the glucose administration was increased. This suggests that glucose administration to maintain blood glucose level between 150 and 250 mg/dl is essential for the AKBR recovery above 1.0 that accompanies the normalization of graft metabolic functions, and that, along with the postoperative minimal increase in serum enzymes and favorable outcome of the transplant with no incidence of a primary nonfunctioning graft, the prompt and successful recovery of AKBR reflects the expected high viability of the graft in our LRLT cases.

Adolescent↗
PubMed1993

Hepatic vein reconstruction of the graft in partial liver transplantation from living donor: surgical procedures relating to their anatomic variations.

BACKGROUND: The surgical procedures to reconstruct the hepatic veins differ according to their anatomic variations to obtain the optimal graft volume for the recipient. This is an overview of the procedures used in our 25 living related liver transplantations. METHODS: The donor/recipient body weight ratio ranged widely from 1.2:1 to 9.6:1 (5.3 +/- 0.5:1, mean +/- SEM). RESULTS: The graft weight/recipient body weight was 2.40% +/- 0.21%. Graft components, which were determined by the optimal graft volume, and their drainage veins were the following: (1) segments 2 and 3 (S2+3) were used in 13 cases, 11 with the left hepatic vein (LHV) and two with the LHV and a partial drainage vein of S3; (2) S2+3 and a part of S4 in eight cases, seven with LHV and one with LHV and a partial drainage vein of S4; (3) S2+3+4 in three cases, with the common trunk of LHV and middle hepatic vein in all cases; and (4) S5+6+7+8 in one case with right hepatic vein. In two of three cases in which the graft had two drainage veins, the two vessels were reformed to have a common anastomotic orifice by the back-table plastic surgery procedure. In the other case in which the procedure could not be performed, two separate anastomoses of the individual vessels were performed successfully. Although stenosis of the reconstructed hepatic veins occurred four times in two cases at 3 months or more after transplantation, all incidences could be completely repaired by balloon dilation. CONCLUSIONS: These results show that, with careful consideration of the hepatic vein reconstruction, pediatric patients can receive optimal volume grafts from living donors.

Adolescent↗
PubMed1993

Plasma amino acid profile in relation to arterial ketone body ratio in surgical patients.

A total of 357 plasma amino acid profiles from 93 surgical patients were statistically analyzed in relation to the changes in arterial ketone body ratio, which reflects the hepatic mitochondrial redox state. When the arterial ketone body ratio was above 0.7, all plasma amino acid levels were within the normal range. When it was between 0.7 and 0.4, plasma levels of aspartate, glutamate, valine, isoleucine, leucine, ornithine, and arginine decreased, and plasma levels of tyrosine, phenylalanine, proline, and methionine increased. Furthermore, when it was below 0.4, almost all plasma amino acids markedly increased. These results indicate that arterial ketone body ratio accurately reflects the alterations in plasma amino acid profile, and can serve as an indicator for providing nutritional support by amino acid supplement in surgical patients.

Adult↗
PubMed1993

Decreased adenylate energy charge and superoxide anion release in polymorphonuclear leukocytes in septic patients after hepatectomy.

To clarify the process of multiple organ failure after hepatectomy, the adenylate energy charge (EC) and superoxide anion (O2-) release of polymorphonuclear leukocytes (PMN) were measured 19 times on 11 septic patients after curative hepatic resection in relation to arterial ketone body ratio (AKBR), which reflects hepatic mitochondrial redox potential. PMN EC was measured by labeling the adenine nucleotide pool of PMN with radioactive adenine. The data of the septic patients (n = 19) was divided into two groups according to the hepatic energy status: AKBR above 0.7 (septic state A; n = 8) and AKBR below 0.7 for at least 3 successive days (septic state B; n = 11). Thirteen nonseptic patients undergoing hepatic resection were applied to the control group, and all of them showed AKBRs higher than 0.7. The PMN EC of septic patients was significantly lower than that of nonseptic patients [0.80 +/- 0.01 (SEM) vs. 0.88 +/- 0.02, P < 0.01]. In septic patients, moreover, the PMN EC of septic state A was significantly higher than septic state B (0.85 +/- 0.01 vs. 0.77 +/- 0.03, P < 0.05). Superoxide anion release of septic patients was significantly lower than that of nonseptic patients (19.0 +/- 2.1 nmol/5 x 10(5) cells/15 min vs. 29.3 +/- 1.7 nmol/5 x 10(5) cells/15 min, P < 0.01). Superoxide anion release of septic state A was significantly greater than that of septic state B (26.0 +/- 2.8 nmol/5 x 10(5) cells/15 min vs. 15.0 +/- 1.9 nmol/5 x 10(5) cells/15 min, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenine Nucleotides↗
PubMed1993

Increased arterial ketone body ratio as a prerequisite for recovery after hepatectomy.

It is reported that a prompt increase in the arterial ketone body ratio (acetoacetate/beta-hydroxybutyrate), which reflects the mitochondrial redox state of the liver graft, is a decisive prerequisite for graft survival in clinical liver transplantation. To contrast the rôle of hepatic mitochondrial redox state in partial hepatectomy with that in hepatic replacement, the changes in the ketone body ratio were investigated in 107 cases of hepatectomy. The ketone body ratio in uneventful cases (n = 70) in the first three days after hepatectomy was significantly higher than that in eventful cases. In the uneventful cases, the ketone body ratios were all increased to above 1.0 within two days after hepatectomy, except in diabetics, whose preoperative values did not reach 1.0 under oral glucose load. However, 20 (22.7%) out of 88 cases whose ketone body ratios promptly increased after hepatectomy had mild to moderate complications thereafter. It is suggested that the recovery of hepatic mitochondrial redox state is also a prerequisite in partial hepatectomy, where a reduced and often damaged liver confronts systemic metabolic load.

Adenoma, Bile Duct↗
PubMed1992

Mitochondrial changes in phospholipid molecular species during the increased oxidative phosphorylation after hepatectomy.

The changes in liver mitochondrial and microsomal phospholipid molecular species were analyzed during the period of remarkably increased oxidative phosphorylation following partial hepatectomy in rabbits. At 24 hours after hepatectomy, phosphorylative activity increased significantly from 69.7 +/- 5.5 to 118.5 +/- 5.7 nmol of ATP synthesized/min/mg protein, compared to the sham operated group. The ratio of phosphatidylethanolamine to phosphatidylcholine (PE/PC) in mitochondria increased significantly in the hepatectomy group compared with the sham operated group. Remarkable changes in molecular species were observed in mitochondrial phosphatidylethanolamine. 1-Stearoyl-2-arachidonoyl species decreased in the hepatectomy group. On the other hand, microsomal phospholipids hardly changed compared with mitochondrial ones. The change in content of 1-stearoyl-2-arachidonyl phosphatidylethanolamine in mitochondria tended to return to normal levels concomitant with the normalization of phosphorylative activity. The changes in content of mitochondrial phospholipids, especially phosphatidylethanolamine, might also be related to enhancement of phosphorylative activity.

Animals↗
PubMed1992

[The effects of centrifugal pump on liver support system with porcine liver perfusion].

The effects of vaneless centrifugal pump (Bio-pump P-80) on energy metabolism were studied, as compared with the roller pump, in an isolated porcine liver perfused with human blood for 6 hours. According to preliminary examination, flow rates were decided to 0.4, 0.8 ml/min/g in roller pump group, in Bio-pump pump group, respectively, not to increase more than 15 mmHg in initial portal pressure. During the perfusion, actual portal pressure was measured and circulatory resistance (portal pressure/flow rate) was calculated before perfusion and hourly after perfusion. Acetoacetate, beta-hydroxybutyrate, lactate and pyruvate, were measured at same times, from which values the ketone body ratio (acetoacetate/beta-hydroxybutyrate, KBR), reflecting the redox state of liver mitochondria, was calculated. In the Bio-pump group, in spite of its high flow, circulatory resistance was low at every hour during the perfusion. KBR was increased rapidly from 0.40 to 1.39, 2.59, 2.75, 2.38, 2.41, and 1.82 and lactate was decreased rapidly from 7.96 to 3.90, 1.77, 1.29, 1.33, 1.34, and 1.25 mmol/L at the respective hours after perfusion. There were significant differences at 2 and 4 hours after perfusion in KBR and after 2 hours of perfusion in lactate as compared with the roller pump group (p < 0.05). These results suggested that the Bio-pump is available for constant and high flow to the liver and helpful to elevate the mitochondrial NAD/NADH ratio (oxidized and reduced forms of free nicotinamide-adenine dinucleotides), leading to and enhancement of metabolic capacity of the perfused liver.

Adult↗