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K Yanaga

Publications and source records attributed to K Yanaga.

At least 55 records · Page 3Linked to original sources
PubMed1997

Significance of donor nutritional status for rewarming injury of the hepatic graft in rats.

We studied the significance of donor nutritional status for hepatic rewarming injury and the usefulness of the glucagon loading test for the assessment of donor nutritional status in rats. In experiment 1, the animals were either free fed or fasted for 6, 24 or 48 h. The livers were preserved in chilled lactated Ringer's solution for 4 h and were divided into eight groups according to the fasting and rewarming periods. The ammonia level in the graft effluent was increased in grafts preserved for 24 h or longer, which was augmented when rewarming time was increased from 15 to 30 min (p < 0.05). In experiment 2, the animals were divided into four groups (n = 3 each) according to the fasting period. The hepatic tissue glycogen content was measured after fasting, and the serum glucose was measured after the administration of 50 micrograms/kg of glucagon i.v. The hepatic tissue glycogen content correlated with the increase rate of serum glucose (p = 0.0001). We conclude that glycogen may protect the hepatic graft from rewarming injury by improving energy status, particularly in prolonged rewarming. The glucagon loading test seems to be useful for assessing the glycogen content of the hepatic graft.

Alanine Transaminase↗
PubMed1997

Analysis of prognostic risk factors in hepatic resection for metastatic colorectal carcinoma with special reference to the surgical margin.

BACKGROUND: Liver resection for metastatic colorectal cancer has been established. Nevertheless, it is still controversial whether the surgical margin from the tumour edge to the cut surface of the liver is a significant prognostic factor in hepatic resection for colorectal metastatic liver cancer. METHODS: To clarify the prognostic risk factors in hepatic resection for colorectal metastasis, univariate and multivariate analyses were performed. Between April 1985 and April 1995, 31 patients underwent curative hepatic resection for metastatic colorectal cancer. The clinical and pathological factors were examined retrospectively. RESULTS: Overall 1-, 3- and 5-year survival rates of the patients were 92, 42 and 39 per cent respectively. Pathological study of 16 resected specimens with a solitary liver tumour revealed hepatic vein invasion by cancer cells in two of 16 cases, portal vein invasion in three, microsatellite lesions in two and biliary tract invasion in six cases. In resected specimens with a solitary tumour measuring less than 4 cm in diameter, one of these factors was observed in only two of nine cases, whereas in specimens with a solitary tumour measuring more than 4 cm in diameter, these factors were observed in six of seven patients (P < 0.05). The distance from the tumour edge to the intrahepatic invasion was less than 10 mm. With univariate analysis, tumour size of 4 cm or more in diameter, an interval of 6 months or less between colorectal and hepatic resection, four or more gross tumours, bilobar involvement and a resection margin from the tumour of less than 10 mm were found to be significant factors indicating a poor prognosis. Cox's proportional hazards model identified a tumour of 4 cm or more in diameter and a resection margin from the tumour of less than 10 mm as poor prognostic factors (P < 0.05). CONCLUSION: In treating metastatic colorectal cancer to the liver, the surgical margin should be more than 10 mm because occult intrahepatic invasion was always found to be located within 10 mm from the edge of the tumour.

Adult↗
PubMed1997

Detection of hepatitis C virus RNA in bile.

OBJECTIVES: The infectivity of bile in patients with hepatitis C virus (HCV) infection remains to be clarified. The purpose of this study was to document the detection of HCV-RNA in bile of patients with HCV infection. METHODS: Bile and serum samples were tested for HCV RNA by a two-step polymerase chain reaction technique in 12 patients with HCV infection. RESULTS: HCV-RNA was detected in the serum of all 12 patients, whereas 6 of 12 bile samples (50%) tested positive. Comparison of laboratory data between patients with and without HCV-RNA in bile demonstrated statistically higher serum total bilirubin among those with positive bile HCV RNA than those without, but other clinical and biochemical variables as well as hepatitis activity scores were comparable between the two groups. CONCLUSIONS: Bile of HCV antibody-positive patients could be infectious.

Aged↗
PubMed1996

Results of 280 liver resections for hepatocellular carcinoma.

OBJECTIVE: To evaluate the recent results of liver resection in patients with hepatocellular carcinoma. DESIGN: Retrospective study. SETTING: A university hospital in Japan. PATIENTS: Two hundred eighty patients who underwent liver resection with complete extirpation of hepatocellular carcinoma from 1985 to 1993. MAIN OUTCOME MEASURES: Morbidity and survival after operation and the pathologic features of hepatocellular carcinoma according to the TNM classification of the International Union Against Cancer. RESULTS: More than 40% of the patients with stages I and II disease underwent a partial resection of the liver, whereas 50% of those with stages III and IVA were operated on with more than a bisegmentectomy. Fifty percent of all patients had no postoperative complications. The morbidities included intra-abdominal abscess (7%), bile leakage (5%), and hepatic failure (4%, of whom half died; mortality rate, 2%). Histopathologically, 32% of the stage I tumors were well differentiated (grade 1), while, in stage III, 56% had portal invasion and 61% had daughter lesions in the liver. The cumulative survival rates of patients with stages I, II, and III disease and all patients at 5 years were 69%, 52%, 32%, and 50%, respectively, while the disease-free survival rates at 5 years were 38%, 34%, 17%, and 29%, respectively. CONCLUSION: The recent results of liver resection for hepatocellular carcinoma are generally satisfactory; however, the recurrence rate is still high.

Aged↗
PubMed1996

Simplified inflow control using stapling devices for major hepatic resection.

We describe the efficacy of a new technique for hepatic inflow division using stapling devices in major hepatic resections. We studied 28 consecutive patients who underwent major hepatic resection at a tertiary referral center by en masse inflow control of Glisson's pedicle in 1993 and 1994, of whom 10 underwent inflow control with stapling devices. Although stapling devices were used for larger tumors (mean +/- SD, 12.2 +/- 8.6 vs 5.7 +/- 5.0 cm; P = .02), the operation time (261 +/- 57 vs 301 +/- 143 minutes), operative blood loss (2071 +/- 1318 vs 4792 +/- 6586 mL), postoperative intra-abdominal bleeding (0% [0/10] vs 17% [3/18]), and hospital stay (16.0 +/- 2.6 vs 20.6 +/- 7.4 days) were favorable for resections with staplers vs resections without staplers; the overall incidences of postoperative complications (40% [4/10] vs 39% [7/18]) and hospital death (10% [1/10] vs 6% [1/18]) were comparable in the two groups. We conclude that stapling devices allow simple, quick, and safe en masse inflow control in major hepatic resections.

Aged↗
PubMed1996

Cardiac complications after hepatic resection.

During a period of 94 months between 1985 and 1993, 474 hepatic resections were performed in 451 patients, of whom 23 (5 per cent) had cardiac problems: ischaemic heart disease in 16 (previous myocardial infarction in five and angina pectoris in 11), arrhythmic disorders in three, valvular disease in three (previous mitral valve replacement in two) and hypertrophic cardiomyopathy in one. The cardiac patients had a higher incidence of cardiac complications (24 versus 0 per cent, P < 0.0001) including two myocardial infarctions, and of non-cardiac complications consisting of postoperative liver failure (16 versus 4 per cent, P < 0.01) and bile leak (16 versus 5 per cent, P = 0.02), as well as hospital death (16 versus 3 per cent, P < 0.001). However, long-term survival was similar in the two groups. Patients with preoperative cardiac conditions appear to be at increased risk for early postoperative morbidity and mortality after hepatic resection.

Adolescent↗
PubMed1996

Thromboxane A2 in preservation-reperfusion injury: the effect of thromboxane A2 synthetase inhibitor.

It has been suggested that thromboxane A2 (TXA) plays important roles in preservation/reperfusion organ injury. In this report, we investigated the prostanoid release from the liver and the effect of a selective TXA synthetase inhibitor (E)-3-[p-(1H-imidazol-yl-methyl)-phenyl]-2-propenoic acid, OKY046) during cold preservation and after reperfusion. Rat livers were preserved in lactated Ringer's solution at 4 degrees C for 2, 4, and 6 hr and perfused with oxygenated Krebs-Henseleit buffer using recirculating perfusion system, and prostanoids were measured during cold preservation and after reperfusion. OKY046 and a novel TXA receptor antagonist [(9,11), (11,12)-Dideoxa-9a, 11a-dimethyl-methano-11,12-methano-13,14-dihydro-13-aza-14-oxo-15-cyclo pentyl-16,17,18,19,20-pentanor-15-epi-TXA, ONO3708] were added into the preservation solution and perfusate. Along with the preservation time, both the production and release of TXA was observed to increase; however, almost all the produced TXA was stored in the liver tissue. Afterwards, the stored TXA was released into perfusate in 15 min after reperfusion. OKY046 significantly decreased both the production and release of TXA. In addition, OKY046 improved the histological damage and trypan blue uptake of liver cells. Our results demonstrate that TXA, stored in the liver during preservation, might therefore be a potential trigger of reperfusion injury, and as a result, OKY046 reduces reperfusion injury by decreasing the production of TXA during preservation.

6-Ketoprostaglandin F1 alpha↗
PubMed1996

Tuberculosis following liver transplantation: report of a case and review of the literature.

We report on a 44-year-old man who developed tuberculosis 4 months after liver transplantation. The diagnosis was confirmed using a polymerase chain reaction (PCR) technique in bronchial alveolar lavage (BAL) fluid, and the patient was successfully treated by reducing his immunosuppression and administering antituberculous drugs. The patient became afebrile 20 days after starting antituberculous therapy and remains well at home. A review of the literature revealed that tuberculosis after liver transplantation is a rare complication with a reported mortality rate of as high as 40%. The mortality is highest for patients who become symptomatic within 3 months after transplantation (83% vs 0%, P < 0.01; Fisher's exact test) and for those with an interval between the initial symptom and diagnosis of more than 2 weeks (71% vs 0%, P < 0.05). Early diagnosis is, therefore, essential for successful resolution of tuberculosis after liver transplantation.

Adult↗
PubMed1996

Assessment of hepatic graft injury by graft effluent in rodents: N-acetyl-beta-glucosaminidase and type III procollagen peptide.

We studied the significance of N-acetyl-beta-glucosaminidase (beta-NAG) and type III procollagen peptide (P-III-P) in the effluent of rodent hepatic grafts. After total hepatectomy, the livers were preserved in chilled, lactated Ringer's solution and then divided into five groups (n = 10 each): group 1, 4 h preservation only; group 2, 4 h preservation and rewarming; group 3, 6 h preservation only; group 4, 6 h preservation and rewarming; and group 5, minimal preservation only. The beta-NAG of groups 2 and 4 was significantly higher than that of groups 1 and 3 (0.98 +/- 0.5 U/l vs 0.21 +/- 0.12 U/l; P < or = 0.01 and 1.76 +/- 0.67 U/l vs 0.38 +/- 0.25 U/l, respectively; P < or = 0.01), while that of group 4 was significantly higher than that of group 2 (1.76 +/- 0.67 U/l vs 0.98 +/- 0.50 U/l; P < or = 0.05). The P-III-P of group 4 was significantly higher than that of group 2 (0.133 +/- 0.008 U/ml vs 0.110 +/- 0.015 U/ml; P < 0.01). We conclude that beta-NAG is a novel parameter of parenchymal and nonparenchymal cells, while P-III-P reflects the integrity of the hepatic sinusoidal extracellular matrix.

Acetylglucosaminidase↗
PubMed1996

Surgical treatment strategy for patients with stage IV hepatocellular carcinoma.

BACKGROUND: This study was conducted to identify the prognostic indicators for patients with stage IV hepatocellular carcinoma (HCC), as well as to clarify the strategy of surgical treatment for those patients. METHODS: Forty-six patients with stage IV HCC were included in this study. Prognostic factors were univariately and multivariately analyzed. Furthermore, the significance of intraoperative treatment for residual tumors was investigated in patients with an absolute noncurative operation. RESULTS: The poor prognostic factors were as follows: host factors, Child's classification of B and C and immunosuppressive acidic protein level of greater than 400 micrograms/ml; tumor factors, tumor diameter of greater than 5 cm, poorly differentiated histologic features, positive portal vein invasion, and intrahepatic metastases involving more than three segments; others, an absolute noncurative operation and no preoperative treatment. Tumor diameter of more than 5 cm was then suggested to be an independent prognostic indicator. Survival of patients with stage IV-A HCC who underwent a curative operation was similar to that of those with stages III HCC: Furthermore, the survival of patients with Stage IV-A who had an absolute noncurative operation but underwent either intraoperative microwave coagulation or ethanol injection to the residual HCCs was not statistically different from that of those with a curative operation. CONCLUSIONS: Therefore for stage IV-A HCC surgical treatment is considered to be both useful and the first choice of treatment when all the tumors in the liver can be removed or when the residual tumors can be treated during operation by either microwave coagulation or ethanol injection as a result of an incomplete removal of the tumors.

Adult↗
PubMed1996

Prognosis of recurrent hepatocellular carcinoma: a 10-year surgical experience in Japan.

BACKGROUND & AIMS: Little has been addressed on the characteristics and prognostic factors of recurrent hepatocellular carcinoma after undergoing a hepatic resection for primary hepatocellular carcinoma. The aim of this study was to clarify the aforementioned matters of recurrent hepatocellular carcinoma. METHODS: One hundred fifty-nine patients with recurrent hepatocellular carcinoma were studied retrospectively. Twenty-four clinicopathologic variables, including the period until recurrence (less than or more than 1 year), types of recurrence (intrahepatic nodular type, intrahepatic multiple type, and extrahepatic type), and types of treatment after recurrence (no treatment, lipiodolization, ethanol injection, or hepatectomy) were univariately and multivariately analyzed. RESULTS: The following three variables were finally selected as independent and prognostic indicators after recurrence: (1) period until recurrence, (2) type of recurrence, and (3) types of treatment after recurrence. CONCLUSIONS: The prognostic factors in patients with recurrent hepatocellular carcinoma were as follows: (1) period until recurrence, (2) types of recurrence, and (3) types of treatments received after recurrence. The establishment of a follow-up system, including an examination for extrahepatic recurrence, and the development of an effective method of adjuvant chemotherapy are required to obtain better treatment results.

Aged↗
PubMed1996

Tolerance of the cirrhotic liver to cold ischemia: ex vivo analysis in rats.

We investigated the viability of rat cirrhotic livers preserved cold using an isolated rat liver perfusion model. Cirrhosis was induced by intravenous thioacetamide injection. Normal and cirrhotic livers were reperfused immediately or following 6 h of preservation through the portal vein with Krebs-Henseleit buffer and hyaluronic acid added. Cirrhotic livers with short cold ischemia showed higher portal venous resistance than their normal counterparts (p < 0.05), while cirrhotic livers preserved for 6 h exhibited marked elevation of the portal venous resistance as compared with their fresh counterparts or normal liver preserved cold for 6 h (p < 0.05). Similarly, the oxygen consumption of cirrhotic livers with short cold preservation was lower than that of normal livers (p < 0.05), which was further reduced by 6 h of cold preservation (p < 0.05). The bile output was not different between normal and cirrhotic livers. The sinusoidal endothelial cell function of cirrhotic livers as assessed by the clearance of hyaluronic acid was impaired even after a short period of cold ischemia. Histologically, cirrhotic livers showed severe sinusoidal endothelial cell damage, hepatocellular swelling, and marked septal edema which became more prominent by cold preservation. We conclude that the viability of the cirrhotic liver is impaired even by a short cold exposure, and that the prolongation of cold ischemia of the cirrhotic liver leads to further deterioration of the viability.

Animals↗
PubMed1996

Characteristics of hepatocellular carcinoma associated with extrahepatic primary malignancies in southern Japan.

OBJECTIVES: This study was conducted to clarify the characteristics of patients with extrahepatic primary cancers (EHPC) associated with hepatocellular carcinoma (HCC), as well as to investigate the influence of EHPC on both patient survival and disease-free survival after hepatic resection. METHODS: Forty-one of 463 patients who underwent hepatic resection were included. The clinicopathological factors, including survival, were compared between patients with and without EHPC. We also compared the same factors among the prehepatectomy, synchronous, and posthepatectomy groups. Different types of extrahepatic cancers were also investigated in detail. RESULTS: Gastric and colorectal cancers were the most common EHPC. No definite relationship was observed between HCC and other specific cancers such as B-cell lymphoproliferative disorders. There also were no differences in either the liver function tests, alpha-fetoprotein, or prognostic pathological indicators such as portal vein invasion and intrahepatic metastases. In addition, we found no difference in patient survival between the patients with and without EHPC. However, disease-free survival rates in patients with EHPC were significantly higher than in those without EHPC. Patients in the prehepatectomy group were older than those in the synchronous and posthepatectomy groups, and no positive hepatitis B surface antigen was found in the prehepatectomy group. Patient survival was significantly higher in the posthepatectomy group than in the prehepatectomy group; however, no significant difference in disease-free survival was found among the three groups. Only one patient died of EHPC. CONCLUSIONS: No specific clinicopathological factors were observed in patients with HCC associated with EHPC. Furthermore, EHPC had no adverse effect on either patient survival or disease-free survival after hepatic resection. The predominant cancer was gastric cancer, whereas the most frequent cause of death was HCC itself. Therefore, a strict follow-up of HCC--as well as screening for the most common cancers, such as gastric cancers in southern Japan--should be required for patients with HCC associated with EHPC.

Carcinoma, Hepatocellular↗
PubMed1995

Significance of hyaluronic acid for evaluation of hepatic endothelial cell damage after cold preservation/reperfusion.

UNLABELLED: Serum hyaluronic acid (HA) levels during or after liver transplantation can reflect graft viability in animal models. Decreased HA clearance in nonviable grafts seems to reflect hepatic endothelial cell damage induced by cold preservation/reperfusion. Therefore, we examined the relationship between HA clearance and endothelial cell damage, using an isolated perfused rat liver (IPRL) model. The grafts were separated into four groups, according to cold preservation time: minimal storage ( CONTROL: n = 9), 4-hr preservation (n = 9), 5-hr preservation (n = 8), 6-hr preservation (n = 9). After cold storage, grafts were put on the recirculating IPRL system and then reperfused for 120 min with 37 degrees C oxygenated Krebs-Henseleit buffer, containing HA and sodium taurocholate. To examine the function of sinusoidal endothelial cells and hepatocytes, serial measurements of HA, total bile acids, and conventional parameters in the perfusate were taken. After the perfusion, a trypan blue exclusion test was done to assess the microscopic sinusoidal lining cell (SLC) damage. HA clearance from the perfusate showed a preservation time-dependent decrease which clearly distinguished between 4- and 6-hr preserved grafts. Trypan blue uptake ratio of SLC increased in accordance with preservation time. HA clearance at 120 min after reperfusion showed a highly significant correlation with histologically assessed SLC damage. These results suggest that HA is useful to evaluate the extent of endothelial cell damage after cold storage and reperfusion. The significance of HA as a predictor of graft viability is also confirmed.

Animals↗