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Biomedical subjects

S Ogata

Publications and source records attributed to S Ogata.

At least 199 records · Page 11Linked to original sources
PubMed1987

Chemical identification of lipid components in the membranous form of rat liver alkaline phosphatase.

Membranous and soluble forms of rat liver alkaline phosphatase were selectively prepared by extracting microsomes with n-butanol at pH 8.5 and 5.5, respectively, and purified in homogeneous forms by the method previously established (Miki et al. (1986) Eur. J. Biochem. 160, 41-48). When subjected to polyacrylamide gel electrophoresis, the two forms migrated to the same position in the presence of sodium dodecyl sulfate, while the membranous form remained at the top of gels in the absence of the detergent. Treatment of the membranous form with phosphatidylinositol-specific phospholipase C resulted in its conversion to a soluble form with the same electrophoretic mobility even in the absence of the detergent as that of the soluble form extracted at pH 5.5. Automated Edman degradation analysis showed that the two forms have the same N-terminal amino acid sequence up to the 30th residue determined. Chemical analyses of hydrolysates of the two forms by gas-liquid chromatography demonstrated that the membranous form contains palmitic acid, stearic acid, and inositol, while the soluble form contains inositol but is devoid of the fatty acids. Taken together, these results suggest that rat liver alkaline phosphatase is covalently attached to phosphatidylinositol acylated with palmitic acid and stearic acid, which functions as the membrane-anchoring domain of the enzyme molecule.

Alkaline Phosphatase↗
PubMed1987

Role of the kallikrein-kinin system in two-kidneyed and one-clipped hypertensive rats.

The influence of aprotinin as a kallidinogenase inactivator on the antihypertensive effect of angiotensin I converting enzyme inhibitor (CEI) was studied in two-kidneyed and one-clipped hypertensive rats. Sixteen two-kidneyed and one-clipped hypertensive rats and sham-operated normotensive rats were prepared for this experiment. They were divided into two groups: those with the aprotinin infusion and those without. The effects of the oral administration of CEI were compared as regards mean arterial pressure (MAP) and urinary kallikrein activity (UKA). In 8 hypertensive rats under glucose infusion, MAP fell from 184.4 +/- 4.5 to 106.3 +/- 5.2 mm Hg, and UKA changed from 1.37 +/- 0.18 nkat/12 h to 0.61 +/- 0.11 nkat/12 h after the administration of CEI. In the remaining hypertensive rats under aprotinin infusion, MAP decreased from 175.0 +/- 3.0 to 140.6 +/- 5.1 mm Hg, and UKA slightly changed from 0.72 +/- 0.25 nkat/12 h to 0.59 +/- 0.12 nkat/12 h. Thus, the decrease of MAP after the administration of CEI was suppressed by the aprotinin infusion, and this significant difference was supported by the decrease of UKA. As for 16 normotensive rats, CEI did not alter MAP, nor did aprotinin have any effect on it. However, UKA tended to decrease after the administration of CEI. These results suggest that both the kallikrein-kinin system and the renin-angiotensin system play an important role in the maintenance of high blood pressure in two-kidneyed and one-clipped chronically hypertensive rats.

Animals↗
PubMed1987

The relationship of borderline personality disorder to the affective disorders.

The proposition that Borderline Personality Disorders (BPDs) are atypical forms of affective disorder is reviewed in the light of pharmacological, outcome and clinical studies. The case can be summarized briefly as follows: that the basic underlying cause of borderline symptomatology is an effective disorder; that mood disturbance, which is viewed as primarily biological, is more important than developmental experience and life events in maintaining borderline personality features; that therapies aimed at treating the mood disorder should therefore be expected to relieve the personality disorder. However, the pharmacological studies suggest that antidepressant medications have been largely ineffective in treating well defined BPD, except in the presence of coexisting depressive disorder. Indeed low dose antipsychotics have a demonstrated efficacy in the treatment of BPD, which does not strengthen the case for an affective etiology. Follow-up studies of BPDs suggest that dramatic characterological features seen at the time of index hospitalization tend to recede by the time patients are in their 30s, that major affective disorders fail to emerge over time, and that long-term marginal functioning derives from long-term maladaptive patterns across a variety of areas. Clinical studies suggest that 20-60 per cent of patients with BPD have a concomitant depressive disorder. Conversely the prevalence of personality disorders in depressions varies with depressive category, with considerably higher incidence of personality disturbance found in non-endogenous depression. The high rate of coexistence of these two disorders does not imply causality or primacy, in the sense that it is the affective disorder which brings out and causes the personality disorder. The review concludes that the assertion that BPD represents atypical affective disorder begs the possibility that it is precisely in having borderline features that they are atypical, and hence distinct.

Affective Disorders, Psychotic↗
PubMed1987

Immune responses in Mycoplasma pneumoniae infection of infant mouse and of man.

Infant mice (2 to 4 days old) were exposed to living Mycoplasma pneumoniae. The organisms were isolated in the order of 10(3) to 10(4) colony-forming units from the lungs of mice for 2 weeks after infection. Mononuclear cell infiltration was present in the lungs of infected mice. The specific IgG antibodies to membrane proteins of M. pneumoniae in the sera of infected mice were detected by enzyme-linked immunosorbent assay for about 800 days. In immunoblotting analysis, a 160-kilodalton (kDa) protein strongly reacted with the infected mouse sera. The dams immunized with membrane proteins conferred passive immunity on their offspring via colostrum. Specific IgG antibody appeared in the serum of infant mice that were given mouse anti-M. pneumoniae serum or convalescent human patient serum orally. These mice were also protected from challenge with M. pneumoniae. The immunoblotting patterns of patient sera were similar to those of infected mouse sera. The infant mouse model may be useful to investigate the host immune responses to M. pneumoniae.

Animals↗
PubMed1986

Carbohydrate structures of the third component of rat complement. Presence of both high-mannose and complex type oligosaccharide chains.

We investigated the carbohydrate structure of the third component of complement (C3) newly synthesized by cultured rat hepatocytes. When the cells were incubated with [3H]mannose, [3H]galactose or [3H]glucosamine, these radioactive precursors were incorporated only into the alpha subunit of C3, demonstrating that only the alpha subunit contains oligosaccharide chains. [3H]Mannose-labelled C3 was purified from the culture medium by immunoaffinity chromatography. Oligosaccharides prepared by Pronase digestion and strong alkaline hydrolysis were separated into two fractions by Bio-Gel P-2 chromatography (Fractions I and II). The two fractions were analysed by concanavalin A-Sepharose chromatography, ion-exchange high-performance liquid chromatography, and Bio-Gel P-4 gel filtration before and after sequential exoglycosidase digestions. It was found that Fraction I contained two complex type oligosaccharide chains, (NeuAc)2(Gal)2(GlcNAc)2(Man)3(GlcNAc)2 and (NeuAc)3(Gal)3(GlcNAc)3(Man)3(GlcNAc)2, and Fraction II contained the high-mannose type, consisting mainly of (Man)8(GlcNAc)2. Taken together with the carbohydrate composition of rat serum C3, the results suggest that rat C3 has one high-mannose type oligosaccharide chain and two complex type chains in the alpha subunit, which is different from the proposal for human C3.

Animals↗
PubMed1986

Structural analysis of the asparagine-linked oligosaccharides of rat haptoglobin metabolically labeled in a hepatocyte culture system.

We analyzed the asparagine-linked oligosaccharide chains of rat haptoglobin which were synthesized and secreted by hepatocytes in primary culture. When the cells were incubated with either [3H]mannose, [3H]galactose, or [3H]fucose, all the radioactive precursors were incorporated into the beta subunit of haptoglobin. [3H]Mannose-labeled haptoglobin was purified from the culture medium by immunoaffinity chromatography, and [3H]oligosaccharides were prepared by strong alkali-borohydride treatment. The oligosaccharides obtained were analyzed by anion-exchange high-performance liquid chromatography, concanavalin-A--Sepharose chromatography and Bio-Gel P-4 chromatography before and after sequential exoglycosidase digestions. The oligosaccharides labeled with [3H]fucose or [3H]galactose were also characterized by the above methods. The results indicate that rat haptoglobin contains two complex-type oligosaccharide chains in each beta subunit; one with a possible structure of ( +/- NeuAc----Gal beta----GlcNAc beta----)3(Man alpha----)2 Man beta----GlcNAc----( +/- Fuc alpha----)GlcNAc and the other with ( +/- NeuAc----Gal beta----GlcNAc beta----Man alpha----)2 Man beta----GlcNAc----( +/- Fuc alpha----)GlcNAc.

Animals↗
PubMed1986

Selective preparation and characterization of membranous and soluble forms of alkaline phosphatase from rat tissues. A comparison with the serum enzyme.

We developed a method for selective preparation of two forms of alkaline phosphatase from rat tissues. The enzyme was extracted by n-butanol treatment at pH 5.5 and pH 8.5 as soluble and aggregated (membranous) forms, respectively. The soluble form prepared from liver was found to be identical with the serum enzyme. Complete solubilization of the membrane-bound enzyme without detergents had a great advantage in its purification. Rat hepatoma AH-130 cells enriched in alkaline phosphatase were first used for purification of the liver-type enzyme. The hepatoma enzyme, purified by chromatographies on concanavalin-A-Sepharose, Sephacryl S-300 and hydroxyapatite was used for production of antibodies specific for the liver-type isozyme. An immunoaffinity column, prepared with anti-(hepatoma-enzyme) IgG was utilized for the enzyme purification from other tissues including the membranous form. Analyses of amino acid composition of the purified enzymes revealed that all the liver-type enzymes from hepatoma, liver, kidney and serum had the same composition, whereas the intestinal type consisted of the composition distinctly different from that in the liver type. In addition, there was no significant difference in amino acid composition between the soluble and membranous forms, suggesting a possible involvement in the membranous form of a hydrophobic component other than its polypeptide domain. The present method for selective preparation of the soluble and membranous forms of alkaline phosphatase will be useful for a further investigation on the interaction of the enzyme with membranes.

Alkaline Phosphatase↗
PubMed1986

Isolation and allelic polymorphism of cDNA clones and genomic clones of HLA-DP heavy and light chains.

From a human cDNA library constructed from consanguineous HLA-homozygous cell line AKIBA (HLA-A24, Bw52, DR2, Dw12, Cp63 Cp63: a new DP type), cDNA clones encoding the heavy and light chains of an HLA-DP Cp63 alloantigen were isolated and analyzed by restriction enzyme mapping and nucleotide sequence determination. Allelic comparisons of DP alpha and DP beta cDNA sequences showed that the amino acid sequence of the DP alpha chain was less polymorphic than that of the DP beta chain. In the DP beta chain, the polymorphic region was restricted to the beta 1 domain. We also isolated and characterized 15 genomic phage clones spanning a 74 kilobase (kb) pair of the DP region which were found to contain one DP alpha gene, one DP-like alpha gene, one DP beta gene, and one DP-like beta gene. Genomic blot analyses with different HLA-DP type cell lines using DP alpha cDNA as a probe revealed EcoRI fragment length polymorphism around the DP alpha gene.

Alleles↗
PubMed1986

Purification and characterization of two components of acid alpha-glucosidase from pig liver.

Acid alpha-glucosidase [EC 3.2.1.3] was purified from pig liver by a procedure including Sephadex G-100 affinity chromatography. Electrophoresis on SDS-polyacrylamide gel of the purified enzyme indicated the presence of two components with molecular weights of 73K and 64K. The two components of the enzyme were completely separated, in reasonable yield, by chromatography on a DEAE-5PW column. Both components catalyzed the hydrolysis of the alpha-1,4 and alpha-1,6 linkages of glycogen, maltose, isomaltose, dextrin, and a synthetic glucoside at acid pH. The pH optima of both components were 4.3 for maltase and glucoamylase, and 4.8 for isomaltase and dextrinase. But as to the activity on 4MU-alpha-Glc, the pH optimum of the larger component was 4.8 and that of the smaller component 5.3. The Km values of both components for 4MU-alpha-Glc, maltose, glycogen, isomaltose, and dextrin were 1.0 X 10(-4) M, 9.1 X 10(-3) M, 16.7 mg/ml, 6.7 X 10(-2) M, and 12.5 mg/ml, respectively. Erythritol, Tris, and turanose inhibited the two components competitively. The Ki values of the larger component were 5.0 X 10(-2) M, 13.3 X 10(-3) M, and 3.2 X 10(-3) M, and those of the smaller component were 2.5 X 10(-2) M, 6.1 X 10(-3) M, and 4.7 X 10(-3) M, for erythritol, Tris, and turanose, respectively.

Amino Acids↗
PubMed1986

Multicopy derivative of pock-forming plasmid pSA1 in Streptomyces azureus.

Streptomyces azureus carried one copy or less of plasmid pSA1, which elicited pocks at 0.1 to 1.0%. Strain PK100 was isolated from the wild-type strain after UV irradiation. PK100 carried approximately 20 to 30 copies of pSA1.1, a derivative of pSA1. Plasmid pSA1.1 elicited pocks at 100% and inhibited spore and thiostrepton production.

Plasmids↗
PubMed1985

Growth regulation of human melanocytes: mitogenic factors in extracts of melanoma, astrocytoma, and fibroblast cell lines.

Melanocytes derived from fetal or adult skin do not propagate in vitro unless cultured in the presence of factors such as 12-O-tetradecanoylphorbol 13-acetate (TPA). In a search for physiological factors regulating the growth of melanocytes, extracts of various cultured cell types were tested. Factors produced by melanoma and astrocytoma cell lines support continued proliferation of melanocytes in the absence of TPA. WI-38, a fibroblast cell line derived from human embryonic lung, was the most active source of melanocyte growth factors. No melanocyte growth-promoting activity was found in extracts of cultured neuroblastoma, renal cancer, normal keratinocytes, or renal epithelium. Nerve growth factor, epidermal growth factor, melanocyte-stimulating hormone, transforming growth factor-beta, and platelet-derived growth factor did not have growth-promoting activity for melanocytes. The presence of melanocyte growth factors and TPA together resulted in the strongest mitogenic activity for melanocytes, permitting the recovery (at 20 days) of 4 to 20 times as many cells as in growth factor or TPA alone.

Astrocytoma↗
PubMed1985

Altered synthesis of glucosamine-labeled glycopeptides during postimplantation embryogenesis of the mouse.

Dissected mouse embryos were examined for the ability to synthesize [3H]glucosamine-labeled embryoglycan, which is the glycoprotein-bound large carbohydrate eluted near the excluded volume of a Sephadex G-50 column. Although the ratio of glucosamine-label incorporated into embryoglycan decreased progressively during embryogenesis, 11- and 12-day-old embryos still synthesized significant amounts of the glycan. Severe inhibition of the glycan synthesis was noticed after the 15th day. Therefore, synthesis of the core portion of embryoglycan was suppressed later than when fucosylation of the glycan was known to be suppressed.

Animals↗
PubMed1985

Protective effect of colostrum in Mycoplasma pneumoniae infection induced in infant mice.

The immunological responses and mechanism of maternal immunity in Mycoplasma pneumoniae infection of mice were investigated. ICR female mice, 4 weeks old, and infant mice, 2 to 4 days old, were infected with M. pneumoniae. Anti-M. pneumoniae antibodies in serum and colostrum were determined by enzyme-linked immunosorbent assay. The specific IgG antibody production persisted for 9 months or longer in both the young and infant mice. These infected mice were protected from rechallenge with M. pneumoniae. In addition, the infected dams conferred passive immunity on their offspring. The infant mice born to uninfected normal dams were protected from the challenge with M. pneumoniae when fed by infected foster dams. Conversely, the infant mice born to infected dams were not protected from the challenge with M. pneumoniae when the infants were fed by uninfected dams. The specific IgG antibody appeared in serum of infant mice inoculated orally with M. pneumoniae-infected mouse serum and the infants were protected from challenge with M. pneumoniae, while the infants given protein A-absorbed serum were not protected from the challenge. These results suggest that one of the factors involved in the resistance of infant mice to M. pneumoniae infection is the specific IgG antibody present in the colostrum rather than the result of transplacental transfer.

Animals↗
PubMed1985

Distinct properties of receptors for Dolichos biflorus agglutinin (DBA) isolated from small intestine of adult mice and endoderm cells of early embryos and teratocarcinomas.

Receptors for Dolichos biflorus agglutinin are only expressed in severely restricted cell populations of the mouse. The receptors were isolated from mouse embryos, teratocarcinoma cells, and the small intestine of adult mice. Upon SDS-polyacrylamide gel electrophoresis, all of the receptor preparations migrated as distinct glycoprotein bands; the apparent molecular weights were more than 150 kilodaltons in all cases. The sizes of the carbohydrate moieties determined by gel filtration after alkaline NaBH4 treatment appeared to correlate with the status of cell differentiation. Thus, as has previously been reported, the receptors from teratocarcinoma OTT6050 and embryonal carcinoma cells (F9 and N4-1) contained large amounts of high-molecular-weight carbohydrates eluted near the excluded volume of a Sephadex-G-50 column. The receptors from 6.5-day embryos also contained high-molecular-weight carbohydrates, whose average molecular weight was lower than those obtained from OTT6050, F9, or N4-1. The receptors from PYS-2 parietal endoderm cells, END-C-2 visceral endoderm cells, and the small intestine did not contain significant amounts of the large carbohydrates. These results illustrate the complex nature of the cell-surface changes accompanying cell differentiation.

Animals↗