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Biomedical subjects

T Hanai

Publications and source records attributed to T Hanai.

At least 73 records · Page 4Linked to original sources
PubMed1993

Comparison of prostanoids and their precursor fatty acids in human hepatocellular carcinoma and noncancerous reference tissues.

Eicosanoid production and the compositions of precursor fatty acids were determined in human cancerous and reference liver tissues. Seventeen hepatectomized cases (12 cases of hepatocellular carcinoma (HCC) and 5 cases of metastatic liver cancer) were evaluated. The cancerous tissues and the noncancerous reference tissues were separated, lipids were extracted, and the fatty acids were determined as methyl esters by gas chromatography. Prostanoids (6-keto PGF1 alpha and TXB2) were measured by radioimmunoassay. In HCC, the levels of alpha-linolenic acid (omega-3) (0.41 +/- 0.38 x 100 micrograms/g) and docosahexaenoic acid (10.41 +/- 4.96 x 100 micrograms/g) in liver cancer tissue were significantly less than those in the reference tissues. In HCC, the levels of TXB2 reference (1.86 +/- 2.77 pg/mg wet weight) and 6-keto PGF1 alpha were 10-fold higher than those in reference tissues. We speculate that in HCC higher prostanoid levels in the liver are related in part to tumor metabolism.

6-Ketoprostaglandin F1 alpha↗
PubMed1993

Proliferative activity in the kidneys of aging mice evaluated by PCNA/cyclin immunohistochemistry.

The change of proliferative activity in mouse kidney cortex cells due to aging was studied by PCNA/cyclin immunostaining. Mouse kidney tissues of various ages: late fetal, newborn, suckling, weaning, adult and senescent were used for this experiment. Small pieces of kidney tissues were fixed in methacarn solution and embedded in paraffin. Sections were stained with PCNA/cyclin monoclonal antibody. The reaction product for PCNA/cyclin was observed mainly on nuclei. The ratio of the PCNA/cyclin positive nuclei to the total number of nuclei were calculated. PCNA/cyclin positive ratios in glomeruli and uriniferous tubules in the superficial layer were higher than those in the deep layer from late fetal period to suckling period. They decreased due to aging after birth and became to nearly zero after weaning period.

Aging↗
PubMed1993

Light microscopic radioautographic study of DNA synthesis in the kidneys of aging mice.

The change of proliferative activity in mouse kidney cortex cells during development and aging was studied by detecting S-phase cells by light microscopic radioautography using 3H-thymidine (3H-TDR). Mouse kidney tissues of various ages: prenatal 13.5, 15.5 and 19.0 days of gestation, postnatal 1 and 8 days, 1 and 2 months, and 1 year were used for this experiment. The kidney cortex tissues were labelled with 3H-TDR either in vitro or in vivo and they were processed for light microscopic radioautography. The labeling indices of the respective cell types were calculated. The labeling indices in glomeruli and uriniferous tubules in the superficial layer were higher than those in the deep layer of metanephric cortex through the developmental stages. However, they decreased rapidly after birth and reached low levels (below 4%) from 1 day to 1 year.

Aging↗
PubMed1992

[Postoperative infection control in patients with hepatic, biliary tract, and pancreatic cancers].

Postoperative infection occurs more frequently in patients with malignant disease than in patients with benign disease. Postoperative infection control in patients with hepatic cancer, biliary tract cancer and pancreatic cancer is studied. Although in patients with jaundice due to malignancy the rate of positive bacterial culture of the bile collected at the time of PTCD was low, the rate of positive bile culture increased after 10 to 14 days of PTCD. The predominant strain was Enterococcus spp., followed by Klebsiella spp., Enterobacter spp. and E. coli in that order. These bacteria isolated from the bile were considered to be causative organisms of postoperative infection. Prophylactic antibiotics after the operation for jaundice due to malignancy should be chosen based on the results of bile culture. In patients undergoing hepatectomy, which is considered to be an aseptic operation, gram positive cocci such as S. aureus was the most frequently encountered organism. On the other hand, in patients undergoing hepatectomy and intestinal anastomosis, enteric bacteria were frequently isolated from the infectious foci. In this study there were 6 cases of methicillin-resistant S. aureus (MRSA) postoperative infection, 3 cases after pancreatoduodenectomy, and 3 cases after hepatectomy. Even after an aseptic operation, postoperative MRSA infection is likely to occur in patients undergoing a more invasive operation, so hospital infection control should be again emphasized.

Bacteria↗
PubMed1990

Immunoelectron microscopy of tissues processed by rapid freezing and freeze-substitution fixation without chemical fixatives: application to catalase in rat liver hepatocytes.

We report on the immunohistochemical demonstration of an enzyme at the electron microscopic level using specimens processed by rapid freezing and the freeze-substitution technique without the use of any chemical fixatives. Fresh rat liver tissue blocks were rapidly frozen by the metal contact method using liquid nitrogen, and were freeze-substituted with acetone without any chemical fixatives at -80 degrees C. Some of the freeze-substituted tissues were embedded in Lowicryl K4M at -20 degrees C; the others were returned to room temperature and embedded in Epok 812 at 60 degrees C. Ultra-thin sections were stained using anti-peroxisomal catalase antibody by the protein A-gold technique. The ultrastructure of the hepatocytes was very well preserved compared with that of conventionally processed tissues. The labeling for catalase was confined to peroxisomes. When the labeling density was compared among freeze-substituted tissues and conventionally processed tissues, that of freeze-substituted and Lowicryl K4M-embedded tissues was the most intense. These results show the usefulness of freeze-substituted tissues for immunohistochemical analysis of cell organelles.

Animals↗
PubMed1989

Thromboxane as a possible hepatotoxic factor increased by endotoxemia in obstructive jaundice.

In a study using rats, we investigated whether liver damage induced by endotoxemia in obstructive jaundice is associated with thromboxane (TX) in order to acertain whether its vasoconstrictive and platelet aggregating properties play a role in reducing liver blood flow. The rats were divided into the following 5 groups; a control group, an endotoxin (Et) group, a bile duct ligation (BDL) group, a bile duct ligation and endotoxin (BDL + Et) group and an OKY046 (Thromboxane synthetase inhibitor) treated bile duct ligation + endotoxin (OKY-BDL + Et) group. The blood TXB2 levels in the Et, BDL and BDL + Et groups were higher than those in the control group. The liver TXB2 levels in the Et and BDL + Et groups were also higher than those in the control group. Liver phospholipids and liver blood flow decreased in the BDL + Et group, whereas in the OKY-BDL + Et group they returned close to the control group levels by decreasing the TXB2 levels in both the liver and blood to normal. These results suggest that the high level of TX in the blood and liver tissue may further aggrevate the liver during endotoxemia in obstructive jaundice by inhibiting liver blood flow.

Animals↗
PubMed1989

[Inhibition of thromboxane production might ameliorate liver blood flow in shock].

UNLABELLED: We investigated whether thromboxane (TX), a vasoconstrictor, contributes to liver disturbance in shock by reducing liver blood flow. SUBJECTS AND METHODS: experimental groups: Sham, Et: endotoxin 4mg/kg, BDL + Et: bile duct ligation with Et, OKY. BDL + BDL + Et with infusion of OKYO46 (TX synthetase inhibitor) 5mg, HT: three days after 70% hepatectomy, OKY. HT: HT receiving OKYO46. We evaluated prostanoid and morbidity in hepatectomized cases. MEASUREMENT: TX, liver phospholipid, liver blood flow, endotoxin. RESULTS: Higher TX levels in blood and liver, and reduced liver phospholipid and liver blood flow in BDL + Et returned close to sham by OKYO46. High blood endotoxin in HT decreased by OKYO46. Intraoperative blood losses in cases with postoperative intraabdominal infection or hepatic failure were greater than those without complication. Hepatectomized cases with intraabdominal infection showed higher blood TX than those without complication. TX might be associated with decreased liver blood flow and with postoperative complication during shock. To reduce TX production would be beneficial in shock by ameliorating liver blood flow.

Animals↗
PubMed1988

Immunoaffinity chromatography of lymphocyte subpopulations using tert-amine derived matrices with adsorbed antibodies.

New polymeric solid-phase matrices for cell affinity chromatography were prepared and their advantageous characteristics compared with conventional matrices were highlighted. These new matrices are derivatives of poly(2-hydroxyethyl methacrylate) (PHEMA) containing a slight quantity of amino compounds as a co-monomer. They were applied to immunoaffinity selection between IgG+ and IgG- lymphocytes of the rat mesenteric lymph node. Simple physical adsorption was sufficient for anti-rat IgG antibodies to be immobilized on these matrices, allowing us to omit the laborious procedure of covalent-linking of antibodies on a matrix. As these matrices themselves showed extremely low non-specific adsorption of lymphocytes, a very dilute solution of antibody (0.02-0.08 mg/ml) was enough for column conditioning. This separation method gave IgG- lymphocytes of more than 90% purity and almost 95% yield within as short a time as 7 min. Further, IgG+ lymphocytes were obtained in good yield (80-90% of loaded number) by recovering the adsorbing cell fraction from the column by gentle pipetting of the matrix.

Amines↗
PubMed1986

Brainstem auditory evoked potentials in children with neurodegenerative diseases.

We assessed the usefulness of brainstem auditory evoked potentials (BAEPs) for differentiating types of degenerative diseases in children. The findings of BAEPs were abnormal in one out of two with polioencephalopathies and in seven of the eight with leukoencephalopathies, showing prolonged interpeak latencies of waves I-III, I-V or disappearance of wave components. On the other hand, normal responses were observed in four with corencephalopathies and one with spinocerebellopathy. The serial BAEPs in eight patients had deteriorated with progression of the clinical symptoms. These data on 16 children suggest that BAEPs are indeed a useful tool for monitoring pathophysiologic processes of neurodegenerative diseases.

Adolescent↗
PubMed1986

A case of hereditary motor and sensory neuropathy type III with a decrease in unmyelinated fibers.

We report a 3-year-old girl with hereditary motor and sensory neuropathy type III with a decrease in unmyelinated fibers. There have been few reports of such cases. The present findings suggest the possibility that the primary lesion in this disease is in the axons. We consider that more attention should be paid to the changes in unmyelinated fibers and axons in further studies on this disease.

Child, Preschool↗
PubMed1985

Menkes disease: is vitamin C treatment effective?

The pathogenesis of Menkes disease seems to be linked to metallothionein which binds to copper trapped within cells in some tissues. The only known therapy for this disease is parenteral administration of copper, but the effects are equivocal. We treated a patient with Menkes disease by giving vitamin C orally. The clinical manifestation and bone changes improved and the plasma copper and ceruloplasmin levels gradually increased. Vitamin C may prevent the binding of copper and metallothionein by its reducing effect, and excess copper would be released from the cells. Vitamin C treatment is a simple and physiological method, and should aid in clarifying the pathogenesis of the disease.

Ascorbic Acid↗
PubMed1984

Dielectric analysis of mitochondria isolated from rat liver. I. Swollen mitoplasts as simulated by a single-shell model.

A re-evaluation of the dielectric studies on isolated mitochondria (Pauly, H., Packer, L. and Schwan, H.P. (1960) J. Biophys. Biochem. Cytol. 7, 589-601, and ibid. 7, 603-612) is presented. The suspensions of 'mitoplasts' prepared from rat liver mitochondria by a hyposmotic (10 mM KCl) treatment showed a dielectric dispersion with its characteristic frequency lying in the 1-100 MHz range. In the analysis of data special emphasis was put on the choice of the theoretical models to employ after scrutiny of their applicability to the suspensions tested. As such we adopted the theory of Hanai et al. (Hanai, T., Asami, K., and Koizumi, N. (1979) Bull. Inst. Chem. Res., Kyoto Univ. 57, 297-305) that was advanced to include concentrated suspensions of shelled spheres. Curve fittings based on that theory resulted in a better agreement with experiment than the fittings based on a conventional theory for dilute suspensions. Major findings from our analyses on the swollen mitoplasts are that: (i) the limiting membrane of the mitoplasts has a specific electrical capacity of 1 microF/cm2, (ii) the ratio of permittivity (or dielectric constant) for the mitoplast interior and permittivity for the external medium is 0.6-0.7, and (iii) the conductivity ratio between the interior phase and the medium is approx. 0.6. Reasons for discrepancy between the results of Pauly et al. and ours are discussed.

Animals↗