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Biomedical subjects

T Murata

Publications and source records attributed to T Murata.

At least 19 recordsLinked to original sources

Zinc hydroxide stimulates superoxide production by rat alveolar macrophages.

The effect of zinc hydroxide on superoxide (O2-) production by rat alveolar macrophages was determined by chemiluminescence and by cytochrome c reduction. Zinc ions had no effect on the chemiluminescence of unstimulated alveolar macrophages. By contrast, zinc hydroxide (ZnOH2), a neutralized form of zinc ions, increased the chemiluminescence level and O2- release. Increased O2- release was inhibited by pertussis toxin, isoquinoline sulfonamide and pretreatment with EGTA. These findings indicate that zinc hydroxide formation from zinc compounds can stimulate the O2- production by alveolar macrophages by receptor-mediated and Ca(2+)-dependent process.

Animals

Immunohistochemical detection of extravasated fibrinogen (fibrin) in human diabetic retina.

In diabetic retinopathy, breakdown of the blood-retinal barrier is an early functional disorder that can cause retinal edema, which in turn results in visual disturbance. Hard exudates, composed mainly of lipid and proteinaceous material, are one sign of chronic retinal edema caused by long-standing leakage from the vessels due to breakdown of the blood-retinal barrier. Utilizing diabetic retinas in which hard exudates were present, we performed immunohistochemical staining for fibrinogen. Because fibrinogen is a serum protein, its extravascular localization implies the existence of blood-retinal barrier breakdown. Our studies showed that the extravasated fibrinogen from blood-retinal barrier breakdown accumulated in the hard exudates and in areas of hemorrhage found primarily in the outer plexiform layer and was then phagocytosed by macrophages.

Aged

Effects of multimodal treatment and hyperthermia on hepatic tumors.

The therapeutic results of Lp-TAE (transcatheter arterial embolization in the presence or absence of Gelfoam particles preceded by the infusion of a mixture of lipiodol and an anticancer drug via the proper hepatic artery) or DSM-TAE (transcatheter arterial embolization with degradable starch microspheres and the arterial injection of anticancer drugs via the hepatic artery) combined with hyperthermia were evaluated in 30 patients with hepatocellular carcinoma (HCC), 5 subjects with hepatic cholangiocarcinoma, and 22 patients with metastatic liver carcinoma. Hyperthermia was performed using an 8-MHz Thermotron RF-8. Tumor temperatures could be measured in 31 patients (54.4%) with malignant lesions of the liver who had undergone hyperthermia. The mean maximal temperature (Tmax) was 41.5 degrees C in the metastatic liver cancers. The efficiency of heating in HCC was unfavorable, i.e., the mean Tmax was only 40.7 degrees C. The rise in tumor temperature was greater in either HCC or metastatic liver carcinoma associated with portal invasion of the lesion. The tumor-temperature elevation was also excellent in HCC that had been subjected to embolization with DSM in combination with hyperthermia. The response rate (complete response plus partial response) was as high as 40% (4/10) in the group in which the tumor temperature could be raised to 42 degrees C or more. Among the 52 patients who had shown a high pretreatment level of tumor marker, that value decreased in 34 cases (65.4%), and the decrease was greater than 50% in 22 cases (42.3%).

Antineoplastic Combined Chemotherapy Protocols

A follow-up study of 201 children with autism in Kyushu and Yamaguchi areas, Japan.

A follow-up survey was conducted on 201 young adults with autism who were 18 or older (mean age, 21.5). All had participated previously in intensive therapeutic camping or had therapeutic involvement at medical consultation agencies to evaluate their outcome. Their social outcome was better than that previously reported in Japan. Although 31.5% had shown marked deterioration during adolescence, 43.2% had shown marked improvement during that period. Possible factors contributing to these results are discussed.

Adolescent

Determination of beta-carotene in plasma, blood cells and buccal mucosa by electrochemical detection.

The beta-carotene concentrations in plasma, blood cells and buccal mucosal cells were determined by high-performance liquid chromatography with electrochemical detection. This method was 1,000 times more sensitive than the conventional spectrophotometric method. Polymorphonuclear cells and red blood cells had lower beta-carotene levels than the other cells. After oral administration of 580 mg/day of all-trans beta-carotene to human male volunteers for a week, the beta-carotene concentrations in all cell types increased at least several times above the original levels.

Adult

In vivo-in vitro replicative DNA synthesis (RDS) test using perfused rat livers as an early prediction assay for nongenotoxic hepatocarcinogens: I. Establishment of a standard protocol.

To establish a standard protocol for an in vivo-in vitro hepatocyte replicative DNA synthesis (RDS) test using male F344 rats for screening nongenotoxic (the Ames-negative) hepatocarcinogens, experimental conditions were examined. After treatment with three model hepatocarcinogens, isolated hepatocytes showed highest RDS incidences when plated at a density of 5 x 10(4) cells/ml. Spontaneous RDS incidences in hepatocytes from rats aged 9 weeks or older showed a constant value. The use of hepatocytes from 9-week-old rats at the 5 x 10(4) cells/ml plating density was therefore determined as the standard. Based on the distribution of mean spontaneous RDS incidences over 105 additional experiments (0.4 +/- 0.18%, with SEM), an RDS incidence of over 1% was adopted as the criterion for a positive response in our rat liver RDS test.

Age Factors

In vivo-in vitro replicative DNA synthesis (RDS) test using perfused rat livers as an early prediction assay for nongenotoxic hepatocarcinogens: II. Assessment of judgement criteria.

To better establish in vivo-in vitro hepatocyte replicative DNA synthesis (RDS) test using male F344 rats as a screening assay for nongenotoxic (the Ames-negative) hepatocarcinogens, judgement criteria were assessed after single-gavage treatment with seven model compounds. The profiles of RDS induction by the compounds were analysed in terms of both time-course and dose-dependence. Our data reveal that a value of 2% or more for RDS incidence should be judged as positive and that of less than 1% RDS incidence as negative using maximum tolerance dose (MTD) concentrations in time-course experiments at 15, 24, 39, 48 and 63 h. In the case of an incidence value between 1 and 2%, the finding of a clear dose-dependence was considered to justify the conclusion of a positive effect for 1/4 MTD, 1/2 MTD, MTD and 2 x MTD at a fixed time. The established judgement criteria are planned for introduction in detection of nongenotoxic hepatocarcinogens (the Ames-negative carcinogens) using the RDS test.

Animals

A simple method for the release of asparagine-linked oligosaccharides from a glycoprotein purified by SDS-polyacrylamide gel electrophoresis.

A simple method for the release of oligosaccharides from glycoproteins separated by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) has been developed. Asialo-alpha 1-acid glycoprotein, which was tritiated at the nonreducing terminal D-galactopyranosyl residue by reduction with sodium borotritide after incubation with D-galactose oxidase, was used as a model compound. After electrophoretic separation of the glycoprotein, oligosaccharides were released by the use of a gas-phase hydrazinolysis apparatus. In the first method, the gel was stained with Coomassie Blue and the glycoprotein together with the gel was directly subjected to gas-phase hydrazinolysis after removal of water in a P2O5 desiccator. The recovery of released oligosaccharides was 25.9 +/- 2.4%, based on the amount of the glycoprotein loaded on the gel within the range of 3.5-28.5 micrograms. In the second method, the glycoprotein was electroblotted onto an Immobilon transfer membrane and was visualized by staining with Coomassie Blue. A small piece of the membrane with the corresponding band was cut out, dried in a desiccator and subjected to gas-phase hydrazinolysis. In this case, the recovery of released oligosaccharides was 15.2 +/- 1.0%. These procedures, particularly the first one, should be widely applicable for the isolation of oligosaccharides from glycoproteins separated by SDS-PAGE.

Animals

Methylglyoxal bis(butylamidinohydrazone) exhibits antitumor effect on human malignant melanoma cells but reduces the antitumor action of cisplatin.

The antitumor effect of a polyamine biosynthetic pathway inhibitor methylglyloxal bis(butylamidinohydrazone) (MGBB) on human malignant melanoma (HMG) cells and its combination effect with cisplatin were investigated. The growth of cultured HMG cells was inhibited in a dose dependent manner by either MGBB or cisplatin; complete inhibition of cell proliferation was attained with 5 micrograms/ml of MGBB or 50 micrograms/ml of cisplatin. Pretreatment of HMG cells with MGBB diminished the antitumor action of cisplatin. The cultured HMG cells were inoculated in nude mice and aliquots of the resulting solid tumors (HMG tumor) were transplanted. The growth of transplanted HMG tumors in mice was inhibited markedly by cisplatin (3.8 mg/kg) and moderately by MGBB (10 or 20 mg/kg). The in vivo antitumor effect of cisplatin was also reduced by combined treatment with MGBB.

Animals

Quantitative EEG of elderly schizophrenic patients.

To investigate the brain function of elderly schizophrenic patients, quantitative EEGs of such patients were compared with those of healthy elderly controls. In schizophrenics, increases in delta and slow theta (4.0-6.0 Hz) waves were thought to be due to the influence of antipsychotics. Characteristic EEG features of these patients included the following: 1) more fast theta (6.0-8.0 Hz) wave was observed, with less alpha wave faster than 9.0 Hz, 2) the reduction in alpha 3 (10.0-11.0 Hz) wave was limited to the frontal regions. The present EEG findings are thought to characterize the traits of the subtype of chronic severe schizophrenia. The reduction in alpha 3 wave in the frontal regions may be one expression of the hypofrontality of schizophrenia.

Age Factors

A novel DNA-binding motif abuts the zinc finger domain of insect nuclear hormone receptor FTZ-F1 and mouse embryonal long terminal repeat-binding protein.

Fruit fly FTZ-F1, silkworm BmFTZ-F1, and mouse embryonal long terminal repeat-binding protein are members of the nuclear hormone receptor superfamily, which recognizes the same sequence, 5'-PyCAAGGPyCPu-3'. Among these proteins, a 30-amino-acid basic region abutting the C-terminal end of the zinc finger motif, designated the FTZ-F1 box, is conserved. Gel mobility shift competition by various mutant peptides of the DNA-binding region revealed that the FTZ-F1 box as well as the zinc finger motif is involved in the high-affinity binding of FTZ-F1 to its target site. Using a gel mobility shift matrix competition assay, we demonstrated that the FTZ-F1 box governs the recognition of the first three bases, while the zinc finger region recognizes the remaining part of the binding sequence. We also showed that the DNA-binding region of FTZ-F1 recognizes and binds to DNA as a monomer. Occurrence of the FTZ-F1 box sequence in other members of the nuclear hormone receptor superfamily raises the possibility that these receptors constitute a unique subfamily which binds to DNA as a monomer.

Amino Acid Sequence

A case of amniotic band syndrome with bilateral epibulbar choristoma.

An autopsy case of amniotic band syndrome with bilateral epibulbar choristoma is described. The left eye reveals a complex choristoma and the right eye a dermis-like choristoma. Both choristomatous lesions included lenticular tissue suggesting that rupture of the amnion, which is the initial event of amniotic band syndrome, might have occurred at about the fourth week of gestation. Since the other systemic manifestations of amniotic band syndrome are considered to be compression deformities of the fetus caused by oligohydramnios or amniotic band, the occurrence of epibulbar choristomas in both eyes in this case suggests that a compression mechanism may play a role in the pathogenesis of epibulbar choristoma.

Adult

Reperfusion after a two-hour period of pulmonary artery occlusion causes pulmonary necrosis.

The role of reperfusion injury in the progression to necrosis in pulmonary embolism was evaluated. To simulate this condition, we used a technique that enables occlusion and reopening of the pulmonary arterial branch supplying the right upper lobe in conscious rats. The rats were divided into five groups: the occlusion group (n = 12), in which the pulmonary artery (PA) branch was occluded without reperfusion; the reperfusion group (n = 12), in which the PA branch was reopened after a 2-h period of occlusion; and the reperfusion-SOD (n = 9), reperfusion-IM (n = 8), or reperfusion-IA-SOD (n = 6) groups, in which superoxide dismutase (SOD), indomethacin (IM), or inactivated SOD (IA-SOD), respectively, was administered during reperfusion. The lungs were removed 24 h after the PA occlusion, and histologic examination was performed. In the occlusion group, the alveolar structure of the right upper lobe was well preserved, and there was no erythrocyte or leukocyte accumulation. The only significant changes compared with the control lobe was the appearance of wavy internal elastic lamina of the PA and slight neutrophil adherence to the endothelial cells. In contrast, the right upper lobe of the reperfusion group disclosed numerous foci of hemorrhagic necrosis, with disrupted alveoli and leukocyte accumulation in all cases. With SOD treatment, the changes compatible with hemorrhagic necrosis were attenuated to the level of the control lobes. However, neither IM nor IA-SOD decreased these changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Endothelial function in thrombosis and thrombolysis.

The localization of tissue factor (TF) in atherosclerotic plaques of human aortas was immunohistochemically examined using rabbit anti-IgG against recombinant TF, which was expressed in E. coli. TF, the initiator of the extrinsic coagulation pathway, was ubiquitously present in atherosclerotic intima, and was expressed mainly by macrophages, but not by endothelial cells. It has been suggested that some macrophages in atherosclerotic intima co-express both molecules of TF and platelet-derived growth factor-B chain. We have developed a morphometrically quantitative in vitro assay for angiogenesis, using endothelial cultures on collagen gel incorporating plasminogen. With this method, we have obtained findings suggesting that plasminogen and plasminogen activators (PAs), especially urokinase-type PA (uPA) derived from endothelial cells, enhance angiogenic activity, probably by increasing endothelial migration. uPA was immunohistochemically observed to be primarily cell-associated on the focal contract areas, probably via its receptors on endothelial cells. These findings may support the hypothesis that the activation and regulation of the pericellular fibrinolysis system is closely related to angiogenesis.

Animals

Limitations of compensation by endogenous atrial natriuretic peptide in heart failure.

To evaluate the role of endogenous atrial natriuretic peptide (ANP) in patients with congestive heart failure (CHF), the relationship between plasma ANP and cyclic guanosine monophosphate (cGMP) levels and the prognosis of patients with CHF was examined. In patients with chronic mild to moderate CHF, there was a positive correlation between plasma ANP and cGMP levels (r = 0.81, p less than 0.001). However, there was no significant correlation between these plasma levels in patients with chronic severe CHF, in whom the cGMP concentration reached a plateau in spite of high levels of ANP. The ANP extraction level and the cGMP production level in the pulmonary and systemic circulation correlated significantly in patients with mild CHF. In contrast, there was no significant correlation between the 2 parameters in patients with severe CHF, and the molar ratios of cGMP production to ANP extraction in the pulmonary and systemic circulation were significantly lower than those in patients with mild CHF. In 44 patients with chronic severe CHF who were followed up over 2 years, plasma ANP levels provided more sensitive and specific prognostic information than any other parameters. These results indicate that ANP receptors coupled to guanylate cyclase may be down-regulated in patients with chronic severe CHF, suggesting that high plasma ANP levels as a prognostic predictor may be associated with limitations of compensation by endogenous ANP.

Atrial Natriuretic Factor

Humoral immune responses of cats to feline infectious peritonitis virus infection.

Immunoperoxidase antibody (IPA) method as a titrating method of feline infectious peritonitis (FIP) virus (FIPV) was developed for titrating antibody to FIPV (IPA-titer). By this method the immune responses of the cats that had been infected with FIPV, were traced. The infected cats could be grouped into three types by their immune response to FIPV and clinical appearances. Type I cats lived for a long time, formed a major group among infected cats, had 160 to 1 x 10(4) IPA-titers, and showed healthy appearances without any changes both on autopsy and histopathologically. From among type I cats, type II cats appeared sporadically with rapid elevation of IPA titers to 3.2 x 10(5) and showing clinical signs of FIP, and died. Type III cats lived healthily for a long time with gradual elevation of IPA-titers to a plateau of about 1 x 10(5), then showed neuronal disorder of hind leg paralysis with the descending IPA-titers to 2 x 10(4), and died. Thus, typical FIP appeared as a hyper-immune disease. Other related problems are discussed.

Animals

Multiple endocrine neoplasia type 2A.

A 40-year-old woman was admitted with complaints of headache, palpitation and diaphoresis. She had undergone right hemithyroidectomy 12 years previously. Histological reexamination of the operative specimen revealed a medullary thyroid carcinoma. Abdominal ultrasonography, CT scan and angiography showed bilateral adrenal tumors. Serum catecholamine levels in both adrenal veins were high. Based on these data, bilateral adrenalectomy was performed. Histological examination confirmed the diagnosis of pheochromocytomas. After operation, serum calcitonin and urinary noradrenaline levels were still high. Further examination by 131I-metaiodobenzylguanidine (MIBG) scintigraphy is planned.

Adrenal Gland Neoplasms