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Biomedical subjects

Y Muto

Publications and source records attributed to Y Muto.

At least 289 records · Page 16Linked to original sources
PubMed1992

[Cytofluorometric analysis of DNA content in proliferating cells of coronary arteriosclerotic lesions].

Cytofluorometric determination of DNA content was done on paraffin-embedded tissues of 19 cases of coronary arteriosclerotic lesions including fibrocellular intimal thickening lesions (FT) or atherosclerosis (AS). DNA distribution pattern of medial smooth muscle cells of coronary arteries with FT and AS was all diploid. The average proliferative index (PI) of both medial smooth muscle cells of coronary arteries with FT and AS was 4.8 +/- 0.6. DNA distribution patterns of intimal cells of coronary arteries with FT and AS were also diploid. The average PI of intimal cells of coronary arteries with FT and AS was 8.4 +/- 1.0 and 9.1 +/- 0.7, respectively. These results suggest that intimal cellular proliferation plays an important role in the development of atherosclerosis.

Cell Division↗
PubMed1992

CD30/Ki-1-positive anaplastic large cell lymphoma preceded by Hodgkin's disease.

A 59-year-old man was initially diagnosed as having Hodgkin's disease, nodular sclerosis type, and complete remission was achieved after combination chemotherapy. One year later, he developed a high fever and recurrence of the Hodgkin's disease was diagnosed. Salvage chemotherapy was ineffective, and the patient died. Autopsy specimens showed infiltration of lymphoma cells into multiple organs. Lymph nodes showed characteristics of non-Hodgkin's lymphoma, with expansion of anaplastic large cells; this differed from the histological features at initial diagnosis. Immunohistochemical staining was positive for CD30/Ki-1, but negative for CD15 (LeuM1). These findings were compatible with Ki-1 lymphoma, suggesting that this may be a case of CD30/Ki-1 lymphoma preceded by Hodgkin's disease and that a certain proportion of Ki-1 lymphomas and Hodgkin's disease may share the same cellular origin.

Antigens, CD↗
PubMed1992

Direct evidence that hepatocyte growth factor is a hepatotrophic factor for liver regeneration and has a potent antihepatitis effect in vivo.

Hepatocyte growth factor, a potent mitogen for mature hepatocytes in vitro, seems to function as a hepatotrophic factor for liver regeneration. We examined the mitogenic effect of hepatocyte growth factor on mouse liver in vivo. The labeling index of hepatocytes was markedly increased when recombinant human hepatocyte growth factor was injected intravenously into mice subjected to 30% hepatectomy (control, 1.7% +/- 0.1%; 1 microgram hepatocyte growth factor, 6.4% +/- 1.3%; 5 micrograms hepatocyte growth factor, 18.3% +/- 0.2%) and into mice administered carbon tetrachloride (control, 12.7% +/- 1.0%; 1 microgram hepatocyte growth factor, 26.3% +/- 2.8%) or alpha-naphthylisothiocyanate (control, 0.4% +/- 0.1%; 1 microgram hepatocyte growth factor, 3.8% +/- 1.1%; 5 micrograms hepatocyte growth factor, 14.2% +/- 2.0%). In addition, weights of the remnant livers in mice given hepatocyte growth factor 60 hr after 30% hepatectomy were significantly greater than those of untreated control mice (control, 0.93 +/- 0.04 gm; 5 micrograms hepatocyte growth factor, 1.06 +/- 0.04 gm). Hepatocyte growth factor prevented any marked increase in the serum levels of liver enzymes and bilirubin when it was administered to mice also treated with alpha-naphthylisothiocyanate (control: ALT, 394 +/- 278 IU/L; lactate dehydrogenase, 2,644 +/- 1,109 IU/L; bilirubin, 9.6 +/- 2.6 mg/dl; and 5 micrograms hepatocyte growth factor: ALT, 135 +/- 7.9 IU/L; lactate dehydrogenase, 1,672 +/- 626 IU/L; bilirubin, 1.0 +/- 0.8 mg/dl). Our findings show that intravenously injected hepatocyte growth factor stimulates the growth of hepatocytes in mouse liver and protects the integrity of hepatocytes in vivo against hepatitis caused by hepatotoxin.(ABSTRACT TRUNCATED AT 250 WORDS)

1-Naphthylisothiocyanate↗
PubMed1992

Increased serum apoA-IV concentrations in experimental uremic rats.

Normal histochemical analysis localizes apoA-IV within renal proximal tubules, which suggests that the kidney is a major catabolic site. In clinical renal failure and animal models of decreased renal function, low molecular weight proteins cannot be efficiently filtered through the glomerular basement membrane, and therefore they accumulate in plasma. In normal plasma, apoA-IV exists as both lipoprotein associated and lipoprotein-free, low molecular weight forms. To examine this further, uremic serum apolipoprotein and mRNA levels were examined in surgically 5/6 nephrectomized rats. Compared to sham-operated controls, uremic serum apoA-IV was elevated twofold and was distributed to a greater extent in the lipoprotein-free subfraction. Serum triglycerides were unchanged. Despite finding no correlation between serum apoA-IV and triglyceride levels (in either the d less than 1.006 g/ml or 1.006 less than d less than 1.019 g/ml fraction), serum apoA-IV was positively correlated with the renal function parameters of blood urea nitrogen (r = 0.949, P less than 0.001), creatinine (r = 0.952, P less than 0.001), and uric acid (r = 0.903, P less than 0.001). In addition, the concentration of apoA-IV per milligram of renal homogenate protein in uremic rats was significantly higher than that of control rats, whereas there was no difference in the content of apoA-I between the two groups. ApoA-I, apoA-IV, and apoB mRNA levels in hepatic and in intestinal tissue were undistinguishable between the uremic and surgical sham rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[The clinical usefulness of the molar ratio of branched-chain amino acids to tyrosine (BTR) in discriminating stage of chronic liver diseases].

We determined the molar ratio of branched-chain amino acids to tyrosine (BTR) in plasma and in serum by enzymatic method and compared it with Fischer ratio (the molar ratio of branched-chain amino acids to tyrosine and phenylalanine) in plasma obtained by conventional HPLC method. BTR in plasma and in serum was well correlated with plasma Fischer ratio. The normal range (mean +/- 2SD) of BTR was determined to be 4.41-10.05 in 210 normal subjects. In addition, we investigated the distribution of BTR values in patients with various liver diseases. BTR value decreased according to the severity of liver disease. We evaluated the clinical usefulness of BTR in patients with chronic liver diseases by cumulative distribution analysis (CDA) graph and receiver operating characteristic curve (ROC) analysis. The area under the curve for BTR analyzed by ROC for CH versus LC.HCC group was the highest (86.3%) of any for various concurrently-measured liver function tests, and was significantly higher than AST/ALT, ALT, AST, gamma-GT (each, p less than 0.001) and ALB (p less than 0.05). These diagnostic results showed that BTR is a superior indicator in discriminating between liver cirrhosis and chronic hepatitis.

Adult↗
PubMed1991

Isotopic study of the effects of platelets on development of intimal thickening in autologous vein grafts in dogs.

The effects of platelets on the development of intimal thickening of arterially transplanted autologous vein grafts was investigated using canine poor run-off models. A new apparatus consisting of a shielding lead block to measure in vivo platelet adherence only on the intima of the vein graft was developed. In 23 dogs, 51Cr-labelled platelets (20 microCi/kg) were injected and isotope emission over the grafts was counted. Platelet adherence was expressed as the thrombocyte accumulation index (TAI), i.e. the ratio of counts over the graft under an abnormal flow condition in the poor run-off model to those over the graft under normal flow conditions of the contralateral leg. The TAI of the total graft (TTAI) was significantly high immediately and on the first and third days after implantation. The TAIs of the proximal (PTAI) and distal (DTAI) portions of the vein graft were also high at these same times. At 7, 10, 14 and 21 days, the TAI was almost equal to 1.0, a time at which endothelial regeneration was complete as confirmed by scanning electron microscopy. Thus, the prominent intimal thickening of arterially transplanted autologous vein grafts in dogs, induced under an abnormal flow condition, correlates well with the enhanced platelet adherence on the intima of the vein grafts in an early period after implantation.

Animals↗
PubMed1991

Reduced retinoid content in hepatocellular carcinoma with special reference to alcohol consumption.

Although alcohol is known to enhance hepatocarcinogenesis, the mechanism of this action remains to be explained. To test the hypothesis that ethanol depletes the liver of antitumor promoters such as retinoid, we measured the retinoid concentration in hepatocellular carcinoma tissues and noncancerous surrounding liver tissues in humans known to have a history of alcohol consumption. By high-performance liquid chromatography, the retinoid contents of 29 surgically resected hepatocellular carcinoma specimens and their noncancerous surrounding tissues were measured. Retinoid contents were decreased in both the cancerous and the surrounding noncancerous liver tissues of patients with a high intake of alcohol. The levels correlated inversely with the estimated cumulative lifetime ethanol consumption. The decrease in the retinoid content of hepatic parenchymal cells paralleled that in stellate cells. When compared with the surrounding liver tissues, the cancerous liver tissues were in the state of retinoid deficiency. In summary, alcohol abuse may help promote the hepatocarcinogenesis in man by depleting the liver of the antitumor promoter, retinoid.

Adult↗
PubMed1991

Detection of anti-hepatitis C virus antibody in fulminant hepatic failure.

Serial serum samples obtained from 27 patients with fulminant hepatic failure (FHF) in a variety of etiology were tested for anti-hepatitis C virus antibody (anti-HCV) with uses of two different assay systems. The incidence of anti-HCV in patients with FHF due to hepatitis B (Ortho test system; 7/11, 63.6%: Abbott test system; 9/11, 81.8%) was found to be significantly higher than that in acute HBV hepatitis (Ortho test system; 0/17, 0%) (P less than 0.001). In particular, all 3 post-transfusion HBV-FHF patients were positive for the antibody using both Ortho and Abbott test systems, and cut-off index in those patients was serially increased. On the other hand, cut-off index in anti-HCV positive patients with sporadic hepatitis A virus (HAV)- and HBV-FHF was high even prior to plasma exchange therapy, and gradually decreased. These results strongly suggest that in patients with post-transfusion HBV-FHF, HCV was superinfected over HBV and in the sporadic HAV- and HBV-FHF patients, HAV or HBV were co-infected over HCV carrier. In any events, co-infection and/or superinfection of HCV may play an important role in the development of this fatal disease.

Chi-Square Distribution↗
PubMed1991

Manometric evaluation of esophageal function in progressive systemic sclerosis with special regard to the disease severity.

A study was conducted to elucidate the relation between the severity of progressive systemic sclerosis (PSS) and the grade of esophageal function disorder, the extent of which was estimated using esophageal manometry. Fifty two patients with PSS were divided into the mild, moderate and severe groups according to the severity score established by the PSS Research Group supported by The Ministry of Health and Welfare of Japan. Primary peristaltic pressure in the esophageal body at 25 to 35cm from the incisors as well as lower esophageal sphincter pressure (LESP), which represents the function of the smooth muscle of the esophagus, were significantly decreased in parallel with the increasing severity of PSS. In contrast, there was no significant difference in upper esophageal sphincter pressure (UESP) or in primary peristaltic pressure at 20cm from the incisors, indicating that the function of striated muscle of the esophagus was not impaired. In addition, even in the mild PSS group without dysphagia (19 cases), primary peristaltic pressure in the esophageal body at 25 to 35cm from incisors was found to be significantly decreased in comparison with the control. Hence, esophageal manometry was useful for early detection of the pathophysiological state of the esophageal function in PSS.

Deglutition Disorders↗
PubMed1991

Plasma free amino acid pattern in chronic hepatitis as a sensitive and prognostic index.

To evaluate the diagnostic and prognostic significance of plasma amino acid imbalance in chronic hepatitis (CH), plasma-free neutral amino acid levels were examined in 47 patients with CH, consisting of 8 chronic persistent hepatitis (CPH), 26 chronic aggressive hepatitis (CAH) 2A and 13 CAH 2B, compared with those of 58 patients with liver cirrhosis (LC) and of 12 healthy controls. Fischer's ratio (a molar ratio of branched chain amino acids to aromatic amino acids) was found to be reduced in the order of normal subjects (3.5 +/- 0.4), CPH (3.0 +/- 0.2), CAH2A (2.7 +/- 0.3), CAH2B (2.1 +/- 0.3), compensated LC (LC-C, 1.5 +/- 0.4) and decompensated LC (LC-D, 1.1 +/- 0.2). Patients with CPH showed a significant decrease of the ratio compared with normal subjects (P less than 0.05). The ratio was significantly higher in patients with CAH 2B in comparison with LC-C (P less than 0.001). Especially, the ratio could be used to discriminate the three distinct stages of CH. Discriminant analysis, carried out using six amino acids, Fischer's ratio and conventional liver function tests indicated that Fischer's ratio was the most reliable parameter for differentiation of the three stages of CH. Furthermore, serial examinations of Fischer's ratio in patients with CH remained unchanged in CPH, whereas was significantly reduced in CAH during 2-3 years follow-up. These results strongly suggest that Fischer's ratio is a useful indicator for differential diagnosis and for prediction of the subsequent clinical course of CH as well as being a sensitive index for functional hepatic reserve in chronic active liver diseases.

Adult↗
PubMed1991

A case of leiomyoblastoma (epithelioid leiomyosarcoma) of the greater omentum.

A 59-year-old male complained of a palpable abdominal mass which was revealed to be a primary omental tumor by means of abdominal ultrasonography, computed tomography, angiography and laparoscopy. Histological examinations of the surgically resected tumor further disclosed leiomyoblastoma with positive stainings of both vimentin and desmin, markers for mesenchymal cells and for muscle cells, respectively. He has been well for 2 years since resection, without any relapse or distant metastasis of the tumor. Leiomyoblastoma of the greater omentum is very rare, and is important to distinguish from extraluminal tumor of the abdomen.

Angiography↗
PubMed1991

Significance of tumor necrosis factor (TNF) and interleukin-1 (IL-1) in the pathogenesis of fulminant hepatitis: possible involvement of serine protease in TNF-mediated liver injury.

The effect of tumor necrosis factor (TNF)-alpha and interleukin-1 (IL-1) alpha, which are thought to be principal mediators inducing homeostatic abnormalities during endotoxemia, were investigated on cultured hepatocytes in an attempt to understand their role in the pathogenesis of fulminant hepatitis. Both TNF and IL-1 had no direct cytotoxicity on cultured adult rat hepatocytes as assessed by their effects on protein synthesis and also cytosolic enzyme activity released into the culture medium in the presence of 5 mM D-galactosamine (Ga1N). However, IL-1 caused a dose-dependent inhibition of DNA synthesis in cultured adult rat hepatocytes. Moreover, the serum from TNF-treated rats, prepared after intravenous administration of TNF (5 X 10(4) U per rat), caused a significant increase of enzyme release into culture medium in contrast to control rat serum. The cytotoxicity disappeared when the serum from TNF-treated rats was pretreated by heating at 56 degrees C for 30 min, and was decreased by the addition of the protease inhibitor, aprotinin. In vivo, gabexate mesilate, a serine-type protease inhibitor, prevented GalN/TNF-induced fulminant hepatitis, whereas MX-1, an anti-complement agent, had no such effect. These results strongly suggest that IL-1 has a inhibitory effect on hepatocytes in terms of DNA synthesis and that TNF indirectly induces hepatocellular damage through the serine proteases which are possibly activated by the cytokine in vivo.

Animals↗
PubMed1991

Laser thermal angioplasty for early repair of anastomotic stenosis after lower extremity arterial reconstruction: initial experience.

Laser thermal angioplasty with a sapphire hot-tip Nd-YAG laser system was effectively used for five grafts with anastomotic stenotic lesions which occurred after femoro-popliteal arterial reconstructions. Stenotic lesions were detected by a combination of Doppler flow waveform analysis and ankle/brachial index measurement in 32 femoro-popliteal and five femoro-tibial arterial bypass grafts in the postoperative period. The laser probe used was 3 to 4 mm in diameter. There were no perforations of the arterial wall caused by thermal ablation, even with repeated pulses of 40 watts of laser energy for 3 s. Contact Nd-YAG laser thermal angioplasty using this rounded, 3-4 mm hot-tip facilitated effective widening of the lumen of the anastomotic stenotic lesion. All patients remain well at follow-up from 9 to 20 months after laser thermal angioplasty.

Aged↗