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Biomedical subjects

T Tsuchiya

Publications and source records attributed to T Tsuchiya.

At least 487 records · Page 27Linked to original sources
PubMed1991

[Clinical observation of hemodynamic changes during anaphylactic reaction].

Four cases of anaphylactic shock are reported. In two patients who underwent A-C bypass operation, we evaluated hemodynamic changes systemically when the anaphylactic reaction occurred. At that time it was observed that arterial pressure, central venus pressure, left atrial pressure and systemic vascular resistance decreased and that cardiac index increased. In other two patients it was not possible to evaluate hemodynamic changes during reaction. But one of these two patients developed coronary spasm accompanied with anaphylactic shock and the other patient who had depressed cardiac function and had developed cardiogenic shock, died of cardiac failure after 47 days. It is suggested that hemodynamic changes in anaphylactic reaction varies depending on different general conditions of the patient.

Aged↗
PubMed1991

Psychological studies of emotional changes in children undergoing dental treatment. 1. Changes in plethysmogram.

This study was designed to examine the influence of children's personality traits and parents' child-rearing attitudes on children's internal behaviors before and after treatment. As an indicator of emotional changes, polygraph data and particularly plethysmograms were compared with psychological analysis data of children's personality traits and parental child-rearing attitudes. The subjects were 40 children with slightly carious primary molars, who were out-patients at Aichi-Gakuin University Dental Hospital. The results show that the emotional changes of children undergoing dental procedures are, in fact, observed at the resting pre-treatment stage, and that they are influenced by various factors, including parental child-rearing attitudes and children's personality traits. More over, in the resting post-treatment stage, these factors impinge upon children's emotions in a more complicated manner.

Behavior Therapy↗
PubMed1991

[Role of bile and pancreatic juice in regulation of gut hormone secretion].

To elucidate the role of bile and pancreatic juice in regulation of gut hormone secretion, an experimental study was performed creating models of biliary and pancreatic juice diversion in conscious dogs with reference to gastric acid and pancreatic exocrine secretions. The results were obtained as follows. 1) Diversion of bile from the duodenum to the jejunum, the ileum and urinary bladder (UB) did not affect the postprandial gastric acid and gastrin secretion, except slight suppression of gastric acid in model of bile diversion to the ileum and UB. 2) Postprandial GIP secretion was completely diminished and total-GLI secretion was significantly increased after bile diversion to the ileum and UB, whereas the jejunal diversion did not affect both GIP and total-GLI secretion. 3) A marked hypertrophy of pancreatic acinar cells was seen in conventional histopathological investigation and hyperfunction indicated by microelectroscopical findings was observed after bile diversion to UB with significant hypersecretion of CCK. 4) In the model of bile diversion to UB, hypersecretion of insulin was observed after intravenous glucose infusion test. 5) Diversion of pancreatic juice from the duodenum to the jejunum induced significant postprandial hypersecretion of gastric acid and hyposecretion of GIP.

Animals↗
PubMed1991

[Conversion to 2nd degree from 1st degree atrioventricular (AV) block by the reversal of neuromuscular blockade].

A case of intraoperative conversion to 2nd degree from 1st degree AV block by the reversal of neuromuscular blockade was reported. A 78 year old male, who originally suffered from 1st degree AV block, underwent choledocholithotomy and T-tube drainage for choledocholithiasis. He was administered 4 mg of pancuronium at the time of intubation. The operation lasted for 160 minutes under epidural anesthesia, NLA and nitrous oxide-oxygen. The patient started spontaneous breathing and the recovery was confirmed after the operation which finished without any problem. Neuromuscular blockade was reversed with atropine 0.5 mg and neostigmine 1.0 mg that were administered simultaneously taking 3 minutes. Then he was extubated without any troublesome stimulation. Suddenly, however, he suffered from the worse condition of bradycardia with the 2nd degree AV block. It took about 45 minutes until he recovered to the original 1st degree AV block despite atropine treatment. We believe that this accident was induced by a vasovagal reflex which was triggered by extubation under the effect of neostigmine which acts longer than that of atropine. We should be careful in reversing the effect of the non-depolarizing neuromuscular blockade. A short acting neuromuscular blockade, i.e. vecuronium, is preferable so as to avoid neostigmine reversal, and extubation should be performed when the effect of neuromuscular blockade is confirmed to be exhausted.

Aged↗
PubMed1990

Suppression mutations in the defective beta subunit of F1-ATPase from Escherichia coli.

The Escherichia coli mutant of the proton-translocating ATPase KF11 (Kanazawa, H., Horiuchi, Y., Takagi, M., Ishino, Y., and Futai, M. (1980) J. Biochem. (Tokyo) 88, 695-703) has a defective beta subunit with serine being replaced by phenylalanine at codon 174. Four suppression mutants (RE10, RE17, RE18, and RE20) from this strain capable of growth on minimal plate agar supplemented by succinate were isolated. The original point mutation at codon 174 was intact in these strains. Additional point mutations, Ala-295 to Thr, Gly-149 to Ser, Leu-400 to Gln, Ala-295 to Pro, for RE10, RE17, RE18, and RE20, respectively, were identified by the polymerase chain reaction and sequencing. These mutations, except for RE10, were confirmed as a single mutation conferring a suppressive phenotype by genetic suppression assay using KF11 as the host cells. The results indicated that Ser-174 has functional interaction with Gly-149, Ala-295, and Leu-400. The residues are located within the previously estimated catalytic domain of the beta subunit, indicating that this domain is indeed folded for the active site of catalytic function. Growth rates of the revertants in the minimal medium with succinate increased compared with that of KF11, showing that ATP synthesis recovered to some extent. The ATP hydrolytic activity in the revertant membranes increased in RE17 and RE20 but did not in RE10 and RE18, suggesting that synthesis and hydrolysis are not necessarily reversible in the proton-translocating ATPase (F1F0).

Amino Acid Sequence↗
PubMed1990

Structure of the snake short-chain neurotoxin, erabutoxin c, precursor gene.

A 2.4-kb genomic clone, which encodes the precursor of a snake neurotoxin, erabutoxin c, was isolated from the liver of the sea snake, Laticauda semifasciata. The erabutoxin c gene is about 1.2 kb long and consists of three exons and two introns. The first intron is found at the position corresponding to the signal peptide between amino acid residues 18(Leu) and 19(Gly). The second intron is located at the position corresponding to the central loop of the mature toxin, between amino acid residues 33(Arg) and 34(Gly). A TATA box consensus sequence, characteristic of promoter regions, is identified 29-33 nucleotides upstream from the transcription-initiation site identified by nuclease S1 analysis. The erabutoxin c cDNA nucleotide sequence, deduced from the present work, is compared with the cDNA sequences of erabutoxins a and b reported previously. Replacements are found at three positions, two of which correspond to the amino acid replacements found among the toxins, while the other is silent.

Amino Acid Sequence↗
PubMed1990

[Primary leiomyosarcoma of the pancreas].

Primary leiomyosarcoma of the pancreas is a very rare malignant tumor, with only 12 cases reported. A case of primary pancreatic leiomyosarcoma in a 55 year-old female with diabetes mellitus is described. US and CT demonstrated tumor masses in the head and tail of the pancreas. By angiography, abundant tumor vessels corresponding to the pancreatic tumor masses were revealed in the pancreas. The patient underwent surgical resection of the tumor in the tail of the pancreas, and then, microscopically it was diagnosed as leiomyosarcoma. The tumor in the head of the pancreas was not resected on account of the presence of diabetes mellitus and the possibility of poor prognosis. Macroscopically, it seemed to be the same as the tumor in the pancreatic tail. By operative findings, there was invasion from the pancreatic head to the duodenum and there was nothing to justify suspicion of the extra-ductal growing type of primary leiomyosarcoma of the duodenum. There were no metastases noted at the time.

Diagnosis, Differential↗
PubMed1990

Plasmid DNAs directly injected into mouse brain with lipofectin can be incorporated and expressed by brain cells.

In this study, we demonstrated that lipofectin-treated DNAs which were injected into mouse brain could be incorporated and expressed by brain cells. When L7RH-beta gal plasmid DNA harboring E. coli beta-galactosidase gene fused with the nuclear location signal of SV40 T-antigen gene was injected into brains of 1-week-old mice, cells whose nuclei appeared to be densely stained with the chromogenic substrate X-gal were detected in several portions of the brain till 9 days after injection. Injection of pMLV-CAT plasmid DNA which contains the E. coli chloramphenicol acetyltransferase (CAT) gene also resulted in cells immunoreactive to the anti-CAT antibody.

Animals↗
PubMed1990

Rapid purification and characterization of F1-ATPase of Vibrio parahaemolyticus.

The F1 portion of H(+)-translocating ATPase as purified from membrane vesicles of Vibrio parahaemolyticus by a rapid procedure. The whole purification process (from culture of cells to purification of the enzyme) could be completed in 1 day. The F1-ATPase consists of five subunits (alpha, beta, gamma, delta and epsilon) like F1 of Escherichia coli and other microorganisms. The F1-ATPase of V. parahaemolyticus showed some interesting properties. Its activity was greatly stimulated by high concentrations (about 0.5 M) of SO4(2-), SO3(2-) and CH3COO-, their effects decreasing in this order. Among the anions tested, Cl- and NO3- were ineffective, or rather inhibitory, and cations had no significant effects. Ethanol (or methanol) stimulated the activity 2- to 3-fold. The activity was inhibited by 4-acetamido-4'-isothiocyanostilbene 2,2'-disulfonate (SITS) (an anion exchanger inhibitor), tetrachlorosalicylanilide (TCS) (an H+ conductor), azide and N-ethylmaleimide. Zinc inhibited the activity only slightly, although it strongly inhibited the ATPase activity in membrane vesicles.

4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfo↗
PubMed1990

[Survey of indoor radon concentrations in Fukuoka and Kagoshima prefectures].

It is now well established that radon and its daughter products account for nearly half of the average population exposure to ionizing radiations and that radon is the greatest single source of natural radiation to the population. Radon and its daughters are alpha-emitters, which are more biologically damaging than beta- and gamma-radiations. A nationwide survey of radon concentration was conducted by the National Institute of Radiological Sciences in order to estimate the contribution of radon and its daughters to the population dose in Japan. Authors surveyed indoor radon concentrations in Fukuoka and Kagoshima prefectures as part of this project. A passive type radon dosimeter, in which a sheet of polycarbonate film as the alpha-ray detector was mounted, was used to measure indoor radon concentrations. The resulting distribution of the average annual indoor radon concentrations in both prefectures can be characterized by an arithmetic mean of 24.4 Bq/m3 and a standard deviation of 13.1 Bq/m3, by a geometric mean of 22.2 Bq/m3, and by a median of 20.7 Bq/m3. The geometric means of the distributions for Fukuoka and Kagoshima were 25.4, and 18.4 Bq/m3, respectively. Radon concentrations were also generally high in winter and low in summer. Regarding the analysis of correlations between the concentrations and construction materials, radon concentrations were generally high in Japanese houses with earthen walls and in concrete structures. These results showed that seasons, the type of building materials, and regional differences were significant factors in the variation of indoor radon concentration.

Background Radiation↗
PubMed1990

Detection of a fast isoform of C-protein with an antiserum directed against the N-terminal portion of dystrophin.

An antiserum raised against the N-terminal actin-binding portion of dystrophin cross-reacted with a 130-kDa protein in fast skeletal muscle. The results of purification and two-dimensional gel electrophoresis and its immunological properties demonstrated that this protein is identical to a 130-kDa basic isoform of fast-C-protein. These results suggest that the actin-binding domain of dystrophin shares one or more antigenic determinants with those of C-protein.

Antibodies↗
PubMed1990

Target of serine inhibition in Escherichia coli.

L-serine has long been known to inhibit growth of Escherichia coli cells cultured in minimal medium supplemented with glucose, lactate, or another carbohydrate as the sole source of carbon. However, the target of serine inhibition was not known. The growth inhibition was released by adding isoleucine, 2-ketobutyric acid, threonine or homoserine, but not by aspartate. Thus the inhibition site must be between aspartate and homoserine in the isoleucine biosynthetic pathway. We found that homoserine dehydrogenase I was strongly inhibited by serine. We isolated serine-resistant mutants, and found that in these mutants homoserine dehydrogenase I was resistant to serine. Thus, we conclude that the target of serine inhibition in Escherichia coli is homoserine dehydrogenase I.

Alcohol Oxidoreductases↗
PubMed1990

Concanavalin A affects beta-tubulin mRNA expression during neuritic processes of mouse neuroblastoma N18TG2 cells in a different manner from colchicine.

Addition of concanavalin A (Con A) to mouse neuroblastoma N18TG2 cells cultured with dibutyryl-cAMP which can stimulate neurite outgrowth, stopped the neuritic processes effectively. The extended neurites showed a gradual retraction for at least 8 hrs after addition of Con A, while addition of colchicine caused rapid retraction of the neurites. Immunocytochemistry showed that the addition of Con A did not disorganize the microtubules but the addition of colchicine did. The increase in beta-tubulin mRNA expression which was observed after cell culture and after stimulation by dB-cAMP was suppressed by the addition of Con A. Con A did not affect the beta-tubulin mRNA expression when the cells had already been cultured, while colchicine drastically decreased it. Thus, Con A appeared to affect the beta-tubulin mRNA expression in a different manner from colchicine, probably through inhibition of cell movement.

Animals↗
PubMed1990

[Altered alpha atrial natriuretic peptide (ANP) concentrations in plasma, atria and hypothalamus in experimentally induced hyper- and hypothyroid rats].

In order to assess a possible involvement of thyroid hormone in atrial natriuretic peptide (ANP), experimentally induced hyper- and hypothyroid rats were employed, and the immunoreactive rat ANP (IR-ANP) concentrations in plasma, atria and brain regions including the hypothalamus were measured by a specific radioimmunoassay. Plasma IR-ANP concentration in hypothyroid rats was 14.5 +/- 2.9 (mean +/- SD) fmol/ml, significantly lower than that in control rats (p less than 0.05 vs control of 24.9 +/- 9.7 fmol/ml). Plasma IR-ANP concentration in hyperthyroid rats was 66.4 +/- 9.7 fmol/min, significantly higher than that in the controls (p less than 0.01). Atrial IR-ANP concentration in hyperthyroid rats was significantly lower than that in the controls (79.9 +/- 11.1 nmol/g vs 133.5 +/- 21.2 nmol/g (control), p less than 0.05), though no significant change was observed in atrial IR-ANP concentration in hypothyroid rats. While hypothalamic ANP concentration in hypothyroid rats was significantly lower than that in the controls (17.5 +/- 3.5 pmol/g vs 31.9 +/- 1.9 pmol/g (control), p less than 0.05), there was no significant change of that in the hyperthyroid rats. On reverse phase high performance liquid chromatography, the major peak in plasma and hypothalamus extract was thought to be identical to synthetic alpha-rat ANP (1-28). These results may suggest that in the hyperthyroid state an excessive amount of ANP is released from atria into the blood, and that in the central nervous system thyroid hormone involve ANP metabolism being different from the atrium.

Animals↗
PubMed1990

Teratogenicity of arotinoids (retinoids) in vivo and in vitro.

The effect of structural modifications on the arotinoid molecule, a new class of retinoids, on their teratogenicity in mice was studied. Animals were treated on days 8 and 9 of gestation, the most susceptible stages to retinoid-induced malformations in rodents. The teratogenic potency of the 13 arotinoids tested varied over a dose range of more than five orders of magnitude. Next, we tested whether the quantitative differences in the teratogenicity of these arotinoids correlates with their activity in high density (micromass) cultures of rat embryonic limb bud and midbrain cells. There was a good quantitative correlation between the in vivo teratogenicity and the in vitro activity in limb bud cells but no correlation was found in midbrain cells. Thus, the limb bud cell culture system may be useful for a preliminary testing to select non-teratogenic retinoids. For the risk assessment in humans, however, the in vitro results should be verified in animals studies.

Abnormalities, Drug-Induced↗
PubMed1990

Changes in adrenal neuropeptides content [peptide 7B2, neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP)] induced by pharmacological and hormonal manipulations.

A novel pituitary peptide, designated 7B2, was shown to be present in the adrenal gland. 7B2-like immunoreactivity was mainly localized in the adrenal medulla, similarly to NPY and VIP. In order to elucidate the neural and humoral regulation of adrenal 7B2, NPY and VIP content, Wister rats were treated with reserpine (RES), ranitidine (RANT) or chlorpheniramine maleate (CPhM) for 7-10 days. The thyroid hormone excess and deficient states were experimentally produced with thyroxine (T4) treatment for 2 weeks, methylmercaptoimidazole (MMI) for 4 weeks, or a thyroidectomized state (Tx) for 4 weeks. Orchiectomy or neonatal monosodium glutamate (MSG) treatment was also done. 7B2, NPY and VIP contents were measured by specific radioimmunoassays. RES and RANT treatments caused significant 7B2 reduction (p less than 0.01) and adrenal NPY was significantly decreased by RES (p less than 0.05), while CPhM induced a VIP decreased (p less than 0.05). Orchiectomy did not affect the peptides concentrations, though MSG treatment did cause a reverse change in VIP and NPY. Although T4 administration did not cause any significant change, MMI treatment and Tx induced significant increase (p less than 0.05 or p less than 0.01) in these peptides. Gel or high performance liquid chromatographic analysis revealed the majority of each immunoreactivity coeluted with each standard. These results suggested that adrenal NPY seemed to be coregulated with catecholamine, while VIP was mainly affected by histaminergic control. Furthermore 7B2 might be modulated by both catecholaminergic and histaminergic nervous control. Thyroid hormone deficiency may also affect the amount of these peptides.

Adrenal Glands↗
PubMed1990

Retrovirus-mediated gene transfer into mouse cerebellar primary culture and its application to the neural transplantation.

To develop a procedure for the transplantation of genetically modified brain primary cells, we transplanted cultured mouse cerebellar cells infected with recombinant retroviruses into the cerebella of adult mice and examined the expression of introduced gene-products in the host cerebellum after transplantation. After infection of cultured cerebellar cells with recombinant retroviruses harboring chloramphenicol acetyltransferase (CAT) gene, we selected only virus-infected cells for transplantation by culturing the cells in medium containing G418 for 3 weeks. CAT was continuously expressed in the cultured cerebellar cells during the 3-week incubation, but by immunoblotting analysis with antiglial fibrillar acidic protein (GFAP) or antineurofilament protein (NFP) antiserum the population of cultured cerebellar cells was found to change during the incubation. Immunocytochemical analyses using anti-CAT antiserum demonstrated that the transplanted cell mass containing CAT-positive cells was detectable in the cerebellum up to 3 weeks, but not 3 months after the transplantation of G418-selected cells into the cerebella of 7-week-old mice.

Animals↗