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Biomedical subjects

Y Kishimoto

Publications and source records attributed to Y Kishimoto.

At least 181 records · Page 10Linked to original sources
PubMed1991

Time course of changes in brain energy metabolism of the rat after microsphere-induced cerebral embolism.

The present study was designed to elucidate pathophysiological changes in the brain energy metabolism after cerebral ischemia. Cerebral ischemia was induced in rats by administering microspheres into the right carotid canal, and the time course of changes in cerebral energy metabolism was examined up to the 7th day after the operation. Approximately 50% of the operated rats revealed typical symptoms of stroke. In the right hemisphere, cerebral ATP and creatine phosphate of the rat on the 1st to 7th day were greatly reduced by the microsphere-induced cerebral embolism (maximally 52 and 61%, respectively), whereas the tissue lactate level was increased on the 1st, 3rd and 5th day after the embolism (maximally 125%), suggesting an induction of microsphere-induced cerebral ischemia. These changes in the tissue metabolites were accompanied by a decrease in the mitochondrial oxidative phosphorylation measured in the presence of succinate. A similar trend in the changes of biochemical markers was observed in the left hemisphere, but to a lesser degree or to an insignificant degree. The pathophysiological alterations in behavior and cerebral metabolism of microsphere-injected rats tended to return toward the normal levels on the 7th day after the operation. The results provided information on a useful model for therapeutic studies of anti-ischemic agents in the brain.

Adenosine Triphosphate↗
PubMed1991

Effects of L-dopa or dopamine on human decidual prostaglandin synthesis.

L-Dopa and three catecholamines in the amniotic fluid before and after labor were measured to confirm the amniotic fluid catecholamine levels at the end of gestation. L-Dopa values were higher than those of three catecholamines, and dopamine which was the predominant catecholamine, rose significantly after the onset of labor. Then, to evaluate the effects of L-dopa or dopamine on prostaglandin synthesis, strips of human decidua vera obtained from fetal membranes at the time of elective cesarean sections before the onset of labor were incubated in Krebs-Ringer buffer in the presence of L-dopa or dopamine. When L-dopa was added, the net production of prostaglandin(PG)F was significantly greater than that of the control at each incubation time. On the other hand, the significant rise was observed only after 10 min of incubation for PGE2 production. Dopamine had a stimulatory effect on PGF synthesis only after 15 and 30 min of incubation, and it also stimulated the release of PGE2 at each incubation time. These results suggest that dopamine and L-dopa in amniotic fluid stimulate the production of prostaglandin by the decidua in humans.

Amniotic Fluid↗
PubMed1991

[A study of family communication space (Part I)--A preliminary study on how family communication is actually practiced].

Housing science needs to concern itself with how to improve space for family communication because it plays an important role in human dwelling life. The purpose of this report (Parts I, II & III) is, hence, to elucidate various factors conditioning family communication, and spatial traits of the rooms where it is conducted, based on the survey of the households of students at women's junior colleges. Part I delves into what is specifically communicated within a family and how it is related with other living activities, by grasping how communication is practiced in everyday family life. A basic analysis is made as to how conscious a family members are of their mutual communication, and how rooms are used for it. It has become clear that family communication is closely related with meal-taking both behaviorally and spatially, and that different attitudes among a family members toward family communication cause different modes, and evaluations of it. It has proved to be necessary, for the further studies of family communication, to give an analytical perspective to an in-depth examination of how rooms in the target families are used and how every member views and evaluates their family communication.

Communication↗
PubMed1991

[A study on family communication space (Part II)--A study on spatial utilization for, and familial consciousness of, family communication].

Part II, based on the findings of Part I, tries to identify family Communication by delving into how it is actually practiced in view of spatial conditions within a house, and familial consciousness. Specific spatial conditions have been sampled of the housing of students at women's junior colleges, and how their family members mutually Communicate and evaluate it has been analyzed. Their views of "family" have also been examined. The findings are as follows: 1) The number of rooms, and the width of the room(s) used for family Communication are major determining factors in separating family Communication from other living activities. 2) The above separation is affected by whether family Communication is practiced in a Japanese-style room or a Western-style one. 3) The perceptual difference of the consent of "family" among a family members principally determines how they engage in family Communication and how they evaluate it. It has proved to be necessary to consider, for a spatial analysis, what kind of posture each member takes when mutually Communicating, seeking comfort and relaxation at home.

Adult↗
PubMed1991

[Primary myelofibrosis transforming into multiple subcutaneous monoblastoma--a case report].

A 83-year-old man was diagnosed with primary myelofibrosis based on the presence of leukoerythroblastosis, splenomegaly, chromosome 46 XY, a dry tap bone marrow aspiration and fibrosis on bone marrow biopsy, when he was admitted for herpes zoster in June 1987. He was admitted for a second time with multiple subcutaneous tumors over his entire body in July, 1989. He had mild splenomegaly, but no hepatomegaly nor lymphadenopathy. Laboratory tests were as follows: RBC 214 x 10(4)/microliters, Hb 5.1 g/dl, Ht 17.7%, WBC 3,200/microliters with leukoerythroblastosis, platelets 11.6 x 10(4)/microliters, s-lysozyme 251 micrograms/ml, u-lysozyme 770 micrograms/ml, NAP ratio 98%, score 278. Bone marrow aspiration resulted in a dry tap. Bone marrow biopsy showed marked fibrosis. Histologic examination of subcutaneous tumor biopsy specimens revealed a diffuse infiltration of monocytes with flexuous nuclei. These cells were positive for alpha-naphtyl butyrate esterase stain, and negative for peroxidase, alpha-naphtol ASD chloroacetate esterase stain and platelet glycoprotein IIb/IIIa stain (APAAP). Ultrastructurally, these cells were mostly monocytes and promonocytes, while phenotypically, CD11b, CD13, CD14, CD33 and HLA-DR were positive. These date indicated that the subcutaneous tumors originated from monocytes.

Aged↗
PubMed1990

Determination of saposin proteins (sphingolipid activator proteins) in human tissues.

Saposins are small glycoproteins which are required for sphingolipid hydrolysis by lysosomal hydrolases. Each saposin (A, B, C, and D) stimulates a different enzymatic activity. A new simple HPLC method to determine the levels of saposins A, C, and D in tissue was developed. Tissues were homogenized in 20 vol of water, boiled, and centrifuged. The supernatant was lyophilized and redissolved in 5 ml of water. A 1.5-ml sample of the solution was applied to a reverse-phase HPLC column (C4 column) and eluted with an acetonitrile gradient. Most contaminants eluted from the column prior to the saposins, which were eluted later as a cluster of peaks. This cluster was collected and then analyzed by another HPLC system equipped with an AX-300 anion-exchange column using a NaCl gradient. Saposins D, A, and C eluted from the AX-300 column separately and in that order. Quantitation of the saposins was made by measuring the sizes of each peak. Standard curves made from pure saposins showed that quantification was linear over a range from 1 to 5 micrograms. Saposin B was measured by its stimulation activity on pure human liver GM1 ganglioside beta-galactosidase. Stimulation was linear up to 80 micrograms of saposin B. Application of this method to analysis of human tissues for their saposin content is presented.

Chromatography, High Pressure Liquid↗
PubMed1990

Interaction of saposins, acidic lipids, and glucosylceramidase.

Activity of lysosomal glucosylceramidase is stimulated by two small glycoproteins, saposin A and C, which are, together with two other similar glycoproteins, derived from a single precursor protein. This enzyme is also stimulated by naturally occurring acidic lipids, such as phosphatidylserine and gangliosides. Using highly purified glucosylceramidase, saposins, and acidic lipids, the mechanism of enzyme stimulation was studied by investigating complex formation between the three components and by examining effects on activity caused by changing amounts of saposins and acidic lipids, individually or in combination. The results indicated that acidic lipids form a water-soluble complex with glucosylceramidase but not with saposins and that saposins and acidic lipids each bind to the enzyme at two different sites for the activation. Based on these observations, the previously proposed three-binding sites model of glucosylceramidase, activator, and substrate was modified to one composed of four binding sites: one for carbohydrate of the substrate, one for aglycon, one for acidic lipids, and one for saposins.

Female↗
PubMed1990

An association between alpha 1-antitrypsin phenotype and chronic liver disease.

The phenotypes of alpha-1-antitrypsin have been analyzed by isoelectric focusing on polyacrylamide gels in 232 healthy Japanese blood donors and in 240 Japanese patients with chronic liver diseases: 69 with chronic active hepatitis, 122 with liver cirrhosis, 41 with hepatocellular carcinoma and 8 with primary biliary cirrhosis. The liver cirrhosis patients had a gene frequency of 0.07 for P1*M3, which was significantly higher (P less than 0.01) than that (0.03) in blood donors. The gene frequency of P1*M3 was significantly increased in cryptogenic liver cirrhosis (P less than 0.05), and there was a tendency toward an increased frequency of P1*M3 in post-transfusion groups, and in primary biliary cirrhosis. There were also tendencies toward increased frequencies of P1*M3 in cryptogenic and post-transfusion groups of patients with chronic active hepatitis. The present study indicates that P1*M3 is a genetic or predisposing factor for chronic liver diseases, especially for cryptogenic and/or non A-non B viral chronic liver disease and also for primary biliary cirrhosis.

Carcinoma, Hepatocellular↗
PubMed1990

Alpha-hydroxylation of lignoceroyl-CoA in rat brain microsomes: involvement of NADPH-cytochrome c reductase and topical distribution.

1. The enzymatic mechanism of the alpha-hydroxylation of lignoceroyl-CoA, an intermediate in the synthesis of hydroxyceramide, was studied. In the presence of NADPH, sphingosine and microsomes from 20-day-old rat brain, 14C from [1-14C]lignoceroyl-CoA was incorporated into hydroxyceramide. 2. The alpha-hydroxylation of lignoceroyl-CoA in rat brain microsomes was strongly inhibited by a rabbit anti-immunoglobulin G which was prepared against rat liver microsomal NADPH-cytochrome c reductase. However, anti-immunoglobulin G against cytochrome b5 did not inhibit the alpha-hydroxylase activity. 3. The alpha-hydroxylation activity was more sensitive to trypsin treatment than was NADPH-cytochrome c reductase in rat brain microsomes. This indicates that either alpha-hydroxylase itself or an unknown factor essential in alpha-hydroxylation is highly exposed to the surface of brain microsomes.

Acyl Coenzyme A↗
PubMed1990

Cortical laminar distribution of rat thalamic ventrolateral fibers demonstrated by the PHA-L anterograde labeling method.

The cortical innervation pattern of rat thalamic ventrolateral (VL) fibers was investigated with the Phaseolus vulgaris-leukoagglutinin (PHA-L) anterograde labeling method. The PHA-L-labeled terminals were distributed in the sensorimotor cortex where the cerebello-cerebral (C-C) evoked responses were recognized. The labeled terminals were detected in all layers except layer VI. In the upper part of layer I, the most densely packed terminals were formed and moderately labeled terminals were seen in layers IV and V. Such a laminar distribution of PHA-L-labeled VL terminals is consistent with the profiles of the C-C responses according to laminar field potential analysis.

Animals↗
PubMed1990

Prevention of overt diabetes and insulitis in NOD mice by a single BCG vaccination.

A single intravenous injection of 0.25-1 mg of live BCG organisms at approximately 10 weeks of age produced a potent suppression of insulitis and overt diabetes in non-obese, diabetes-prone (NOD) female mice. Injection of 1 mg of BCG into younger mice, aged 5 weeks, was also very suppressive but the injection into older mice of 15 weeks was somewhat less suppressive. Spleen cell transfer from the BCG-vaccinated NOD mice prevented the occurrence of overt diabetes in the recipients, while the transfer from untreated donors did not. This indicates the generation of some type of suppressor cells in the BCG-vaccinated mice.

Animals↗
PubMed1990

Characterization of a mutation in a family with saposin B deficiency: a glycosylation site defect.

Saposins are small, heat-stable glycoproteins required for the hydrolysis of sphingolipids by specific lysosomal hydrolases. Saposins A, B, C, and D are derived by proteolytic processing from a single precursor protein named prosaposin. Saposin B, previously known as SAP-1 and sulfatide activator, stimulates the hydrolysis of a wide variety of substrates including cerebroside sulfate, GM1 ganglioside, and globotriaosylceramide by arylsulfatase A, acid beta-galactosidase, and alpha-galactosidase, respectively. Human saposin B deficiency, transmitted as an autosomal recessive trait, results in tissue accumulation of cerebroside sulfate and a clinical picture resembling metachromatic leukodystrophy (activator-deficient metachromatic leukodystrophy). We have examined transformed lymphoblasts from the initially reported saposin B-deficient patient and found normal amounts of saposins A, C, and D. After preparing first-strand cDNA from lymphoblast total RNA, we used the polymerase chain reaction to amplify the prosaposin cDNA. The patient's mRNA differed from the normal sequence by only one C----T transition in the 23rd codon of saposin B, resulting in a threonine to isoleucine amino acid substitution. An affected male sibling has the same mutation as the proband and their heterozygous mother carries both the normal and mutant sequences, providing additional evidence that this base change is the disease-causing mutation. This base change results in the replacement of a polar amino acid (threonine) with a nonpolar amino acid (isoleucine) and, more importantly, eliminates the glycosylation signal in this activator protein. One explanation for the deficiency of saposin B in this disease is that the mutation may increase the degradation of saposin B by exposing a potential proteolytic cleavage site (arginine) two amino acids to the amino-terminal side of the glycosylation site when the carbohydrate side chain is absent.

Amino Acid Sequence↗
PubMed1990

Distribution of saposin proteins (sphingolipid activator proteins) in lysosomal storage and other diseases.

Saposins (A, B, C, and D) are small glycoproteins required for the hydrolysis of sphingolipids by specific lysosomal hydrolases. Concentrations of these saposins in brain, liver, and spleen from normal humans as well as patients with lysosomal storage disease were determined. A quantitative HPLC method was used for saposin A, C, and D and a stimulation assay was used for saposin B. In normal tissues, saposin D was the most abundant of the four saposins. Massive accumulations of saposins, especially saposin A (about 80-fold increase over normal), were found in brain of patients with Tay-Sachs disease or infantile Sandhoff disease. In spleen of adult patients with Gaucher disease, saposin A and D accumulations (60- and 17-fold, respectively, over normal) were higher than that of saposin C (about 16-fold over normal). Similar massive accumulations of saposins A and D were found in liver of patients with fucosidosis (about 70- and 20-fold, respectively, over normal). Saposin D was the primary saposin stored in the liver of a patient with Niemann-Pick disease (about 30-fold over normal). Moderate increases of saposins B and D were found in a patient with GM1 gangliosidosis. Normal or near normal levels of all saposins were found in patients with Krabbe disease, metachromatic leukodystrophy, Fabry disease, adrenoleukodystrophy, I-cell disease, mucopolysaccharidosis types 2 and 3B, or Jansky-Bielschowsky disease. The implications of the storage of saposins in these diseases are discussed.

Adult↗
PubMed1990

Bone marrow transplantation in canine GM1 gangliosidosis.

Allogeneic bone marrow transplantation was carried out in an 81-day-old Portuguese water dog with GM1 gangliosidosis using a DLA identical sibling as donor. Engraftment was complete and beta-galactosidase activity in leukocytes of the transplanted dog were similar to those in the donor. Over the next 2.5 months neurological deterioration in the transplanted dog was similar to that in untreated dogs with GM1 gangliosidosis. Cerebral ganglioside GM1 concentrations were not diminished by bone marrow transplantation and cerebral beta-galactosidase activity was negligible. We conclude that allogeneic bone marrow transplantation early in life is ineffective in canine GM1 gangliosidosis.

Animals↗
PubMed1990

Saposins (sphingolipid activator proteins) in the twitcher mutant mouse.

The twitcher mutant mouse, the animal model of Krabbe disease (human globoid cell leukodystrophy), is characterized by apparent deficiency of galactosylceramide beta-galactosidase activity. Saposin A and C, the heat-stable small sphingolipid activator glycoproteins, stimulate the activity of galactosylceramide beta-galactosidase as well as glucosylceramide beta-glucoside. The role of these saposins in the twitcher mutation was investigated. Boiled supernatant fractions, which contained saposins, were prepared from homogenates of twitcher brain, liver, kidney, and spleen. These preparations showed an almost identical effect on the activity of purified glucosylceramide beta-glucosidase (measured by hydrolysis of 4-methylumbelliferyl-beta-glucoside) with similar preparations from control tissues. The effect on the activity of galactosylceramide beta-galactosidase as well as 4-methylumbelliferyl-beta-glucoside beta-glucosidase in the twitcher brain and liver homogenates by authentic saposin A and C was similar to that in control tissues. These results suggest that the twitcher mutation does not affect the concentrations of saposin A or C or their interaction with galactosylceramide beta-galactosidase.

Animals↗
PubMed1990

Mode of action of the gramicidin S analogs lacking hydrophilic amino acid residues on biomembranes.

The gramicidin S analog lacking basic ornithine residues, cyclo(-Val-Ala-Leu-delta Phe-Pro-)2 (where delta Phe represents alpha, beta-dehydrophenylalanine), increased the K+ permeability of human erythrocytes and Staphylococcus aureus similarly to the parent gramicidin S. This analog altered the normal discoid shape of human erythrocytes to an invaginated form. The direction of the shape change was opposite to the case of gramicidin S causing crenated cells. We suppose that the analog accumulated predominantly into the inner half monolayer of membrane and destabilized the membrane structure, resulting in a break in the membrane.

Amino Acids↗
PubMed1990

Influences of TV games on physical and psychological development of Japanese kindergarten children.

The present study was an investigation of playing a TV game and its influences on physical and psychological development of kindergarten children. A self-completed questionnaire was delivered to the parents of 426 children. Of these, 408 had fully completed answers. Questions regarded the amounts of TV game play, its influences on health and on development of children and the attitudes of parents toward the game. Analysis indicated that the kindergarten children, especially boys, played frequently and both the percentage of players and the number of playing hours increased with age. Few adverse effects were reported on vision or other aspects of physical health. Children who played the game had much higher scores on sociability than those with no experience. This seemed to reflect that children acquired a new repertoire of plays from the TV game.

Child Behavior Disorders↗