Biomedical subjects

Y Inoue

Publications and source records attributed to Y Inoue.

At least 847 records · Page 47Linked to original sources

PubMed1996

Cloning of the cDNA encoding the mouse ATBF1 transcription factor.

We have isolated a mouse ATBF1 cDNA which is 12-kb long and capable of encoding a 406-kDa protein containing four homeodomains and 23 zinc-finger motifs. Mouse ATBF1 is 94% homologous to the human ATBF1-A transcription factor. Northern blot and RNase protection analysis showed that levels of ATBF1 transcripts were low in adult mouse tissues, but high in developing brain, consistent with a role for ATBF1 in neuronal differentiation.

Amino Acid Sequence↗

PubMed1996

Induction, localization, and purification of a novel sialidase, deaminoneuraminidase (KDNase), from Sphingobacterium multivorum.

Recently, we reported the discovery of a new type of sialidase, KDNase, which specifically hydrolyzes the ketosidic linkages of 2-keto-3-deoxy-D-glycero-D-galacto-nononic acid (KDN), but not N-acylneuraminyl linkages. We now report that this enzyme, designated KDNase SM, is an inducible enzyme that is localized in the periplasm of Sphingobacterium multivorum. Growth of S. multivorum in the presence of KDN-containing oligosaccharide alditols, KDNalpha2-->3Galbeta1-->3GalNAc alpha1-->3[KDNalpha2--> (8KDN alpha2-->)n-->6]GalNAcol, as a sole carbon source induced KDNase SM activity 15 40-fold, compared with growth in the absence of inducer. KDN, Neu5Ac, or Neu5Ac oligomers were ineffective as inducers. The enzyme was released from the periplasm of induced cells by cold osmotic shock and purified 700-fold to homogeneity. The specific activity of the pure enzyme was 82,100 units/mg of protein. KDNase SM activity resided in a single polypeptide chain with an estimated molecular weight of approximately 47,500. Enzyme activity was maximal at near neutral pH. The availability of pure KDNase will now make it possible to study the structure and functional role of KDN-glycoconjugates and to determine the molecular mechanism whereby the enzyme can discriminate between KDN and N-acylneuraminic acid.

Chromatography, Ion Exchange↗

PubMed1996

Two-dimensional electrophoretic studies on down-regulated intracellular transferrin in human fibroblasts immortalized by treatment with either 4-nitroquinoline 1-oxide or 60Co gamma rays.

The immortalization of human cells is an important early step of carcinogenesis. To investigate the mechanisms of immortalization, we established three immortalized human fibroblast cell lines by treatment with either 4-nitroquinoline 1-oxide (4NQO) or 60Co gama rays. Using two-dimensional gel electrophoresis (2-D PAGE), we identified proteins which are down-regulated in these immortalization cell lines. Their isoelectric points ranged between 5.5 and 6.3, and their molecular masses were approximately 80 kDa. The proteins were also decreased in another human fibroblast cell line immortalized with simian virus 40 (SV40) and two human cervical cell lines. The proteins were present in a cytoskeletal fraction, reacted with anti-transferrin antibody and some of them were phosphorylated. The proteins were identified as transferrin. Although the 2-D PAGE patterns of our proteins and serum transferrin of different origin were distinct from each other, their isoelectric points and molecular weights were similar. We implicate some functions of intracellular transferrin, other than an iron transporter, in immortalization of human cells and discuss a new aspect of transferrin metabolism in the cells.

4-Nitroquinoline-1-oxide↗

PubMed1996

Deletion in the 190 kDa antigen gene repeat region of Rickettsia rickettsii.

The 190 kDa outer membrane protein of Rickettsia rickettsii is a major immunodominant protective antigen which contains 13 tandem nearly identical repeating sequences. We have identified a deletion in the 190 kDa antigen gene of R. rickettsii strain Smith maintained in the laboratory. The deletion occurred within the repeat region of this gene and the mutated repeat region corresponded to one repeating unit in size.

Bacterial Outer Membrane Proteins↗

PubMed1996

Longitudinal effects of age on heat-activated sweat gland density and output in healthy active older men.

To investigate longitudinal effects of age on heat-activated sweat gland density and output, eight healthy active men (mean age 65-70 years) were retested after 5-years using 60-min passive heating [by placing the lower legs and feet in a 42 degrees C water bath while sitting in a warm chamber (35 degrees C and 45% relative humidity)]. Their height, body mass, surface area-to-mass ratio, mean skinfold thickness, resting systolic and diastolic blood pressures, pedometer readings and estimated maximal oxygen uptake did not differ over the 5-years. During the 60-min exposure the increase of rectal temperature was significantly greater in the second test than in the initial test (P < 0.05), although mean skin temperature, metabolic heat production and heart rate did not differ. Total body sweating rate was significantly less in the second test than in the initial test [210 (SEM 13) vs 253 (SEM 16) g.m-2.h-1, P < 0.02]. The mean body temperature at the onset of sweating on the thigh was significantly higher in the second test (P < 0.04), but not on the back. Local sweat rate (msw) had decreased significantly on the back in the second test (P < 0.001), but had not changed on the thigh where it had been smaller (compared to younger men) in the initial test. The decreased msw on the back was due to a lower sweat gland output (SGO) per gland, but not from the recruitment of fewer glands. In contrast, the sweat gland density on the thigh was less in the second test than in the initial test [72 (SEM 4) vs 86 (SEM 7) glands.cm-2, P < 0.03], but the SGO which had shown considerably smaller values in the initial test remained unchanged. These results would suggest that sweat gland function decreased over 5 years in healthy active men in their sixth and seventh decades, despite their having similar physical characteristics and exercise habits. Furthermore, the decline did not occur uniformly over the body surface and it is suggested that it may well extend from the lower limbs to the trunk.

Aged↗

PubMed1996

Regional differences in age-related decrements of the cutaneous vascular and sweating responses to passive heating.

Ten older (aged 64-76 years) and ten younger (aged 20-24 years) healthy men were exposed to a standard heat stress [by placing the lower legs and feet in a water bath at 42 degrees C while sitting in a controlled environment (ambient temperature 35 degrees C and 45% relative humidity) for 60 min]. During passive heating, the rectal temperature of the older men was significantly greater (P < 0.05) and mean skin temperature was lower (P < 0.001), compared to the younger men. Skin blood flow by laser Doppler flowmetry (LDF) was significantly lower on the chest and thigh for the older men (P < 0.001), but forehead LDF did not differ between the groups. The percentages of total LDF in the older men to total LDF in the younger men for the last 30 min were 99%, 58% and 50% on the forehead, chest and thigh, respectively. The age-related differences in LDF responses mirrored cutaneous vascular conductances (CVC), since no group and time effects were observed in mean arterial blood pressure during the test. During the last 30 min the local sweat rates (msw) on the back and thigh were significantly lower for the older men (P < 0.02), but not on forehead, chest and forearm, although the older men had lower msw during the first 30 min exposure regardless of site (P < 0.03). The percentages of total msw in the older men to total msw in the younger men during the last 30 min were 105%, 99%, 63%, 106% and 88% on the forehead, chest, thigh, forearm, and back, respectively. During the latter half of the exposure, the older men had similar LDF, CVC and msw on the forehead, lower LDF and CVC and a similar msw on the chest, and lower LDF, CVC and msw on the thigh, compared to the younger men. These results suggest firstly that regional differences exist in the age-related decrement of cutaneous vasodilatation as well as sweat gland function, secondly that the age-related decrement in cutaneous vascular function may precede a decrement in sweat gland function, and thirdly that the successive decrements may develop sequentially from the lower limbs to the upper body, and head.

Adult↗

PubMed1996

Isolation and identification of novel sulfated and nonsulfated oligosialyl glycosphingolipids from sea urchin sperm.

Novel sulfated and nonsulfated oligosialylglycosphingolipids were isolated from sperm of the sea urchin, Hemicentrotus pulcherrimus, and their structures were established as follows: [formula: see text] This provides the first evidence for the natural occurrence of a tetrasialic acid structure in glycosphingolipids. The finding of sulfated oligosialyl chains is especially noteworthy in that the sulfate group exclusively resides on the C-8 of the nonreducing terminal residues of oligo/polysialyl chains and that sulfation appears to be a termination signal for elongation of oligosialyl chains. Sulfation at the nonreducing terminal Neu5Ac residues of oligosialyl chains was also found to facilitate the formation of an inter-residue lactone between the carboxyl group at the nonreducing terminal sulfated Neu5Ac and the hydroxyl group at C-9 of the penultimate Neu5Ac residue. The long chain base was 4-hydroxysphinganine (t18:0) and the major fatty acid species were identified as C20:1, C21:1, and C22:1.

Animals↗

PubMed1996

Thermoregulatory responses of prepubertal boys and young men in changing temperature linearly from 28 to 15 degrees C.

To examine thermoregulatory responses of prepubertal children to cold stress, 11 boys (aged 8 years) and 11 young men (aged 19-23 years), wearing only trunks, participated in this study. They sat in air at 28 degrees C for 30 min (equilibrium period) and then in conditions where air temperature (Ta) was decreased linearly from 28 to 15 degrees C (at a constant rate of 0.22 degrees C.min-1) for 60 min, at a fixed relative humidity of 65%. In the equilibrium period there was no significant difference between the groups for rectal temperature [Tre, mean 37.30 (SEM 0.10) and mean 37.43 (SEM 0.14) degree C in the boys and the men, respectively] or for the respective skin temperatures (except for the forehead), but metabolic heat production (M) was significantly greater for the boys [mean 57.1 (SEM 1.2) and mean 52.0 (SEM 0.9) W.m-2, P < 0.005]. With declining Ta, the skin temperatures decreased in both groups (P < 0.001), but the decrease was significantly greater for the boys (P < 0.05), especially on the limbs as represented by the thigh and forearm. No significant correlations were observed between the limb skin temperatures compared to surface area-to-mass ratio or limb skinfold thicknesses in either group. The rate of increase in M as Ta decreased was significantly lower for the boys (P < 0.01) largely because of a higher M before the cold exposure. Thus, the mean M during the cold exposure did not differ between the groups [mean 63.6 (SEM 1.1) and mean 61.6 (SEM 1.1) W.m-2 in boys and men, respectively]. When the Ta was lowered, Tre in the boys started falling (P < 0.001), whereas the Tre in the young men did not change for 60 min. The Tre during the 60-min exposure was significantly lower (P < 0.001) for the boys [mean 37.01 (SEM 0.13) and mean 37.48 (SEM 0.18) degree C at the end of the exposure]. It was concluded that when Ta was lowered, the prepubertal boys appeared to vasoconstrict more in their limbs and to be somewhat more hypothermic, compared to the young men.

Adolescent↗

PubMed1996

Clothing microclimate temperatures during thermal comfort in boys, young and older men.

To examine the effects of age-related differences in thermoregulatory function on the clothing microclimate temperature (Tm) and Tm fluctuations while maintaining thermal comfort in daily life, 5 boys (group B, 10-11 years), 5 young men (group Y, 20-21 years) and 5 older men (group O, 60-65 years) volunteered to take part in this study. The subjects were asked to maintain thermal comfort as closely as possible in their daily lives. Tm (temperatures between the skin surface and the innermost garment) at four sites (chest, back, upper arm, and thigh), skin temperature on the chest (Tchest) and ambient temperature (Ta) were measured over a period of 8-12 h from morning to evening on one day in each of the seasons, spring, summer, autumn, and winter. Records of ability to maintain thermal comfort and of adjustment of their clothes were kept by each subject. Ta during periods of thermal comfort did not differ among the groups in any of the seasons. In group Y, Tm was significantly lower at the thigh than at the other sites in spring, autumn, and winter (P < 0.05) and fluctuations (CV) of Tm were significantly larger at the thigh than at other sites in autumn and winter (P < 0.05). Similar tendencies were observed for Tm and CV of Tm in group B. However, Tm and CV of Tm in group O did not differ by site except for the autumn Tm. Group O had a smaller CV at the thigh in winter (P < 0.05), compared to groups B and Y, suggesting a smaller regional difference in Tm fluctuation in group O. Group O adjusted their clothes even on the lower limbs (together with upper body) in order to maintain thermal comfort in accordance with changes in Ta, while groups B and Y did so only on their upper bodies. These results suggest that compared to boys and young men, lower thermoregulatory function in older men may affect Tm and CV of Tm as a result of clothing on lower limbs being adjusted differently in order to maintain thermal comfort.

Adult↗

PubMed1996

Alterations in carrier-mediated glutamine transport after a model of canine jejunal autotransplantation.

The effects of small bowel transplantation (SBTx) on absorptive function are unknown. Preliminary experiments showed a decrease in absorption of glutamine. Our aim was to determine mechanisms of decreased ileal transport of glutamine utilizing a model of intestinal autotransplantation. Seven dogs were studied before and after a model of jejunoileal autotransplantation. In vivo absorption experiments were performed before and two and eight weeks postoperatively with an electrolyte solution containing glutamine (20 mM). In vitro glutamine transport was studied using brush-border membrane vesicles (BBMV) prepared from ileal mucosa obtained from six other dogs and compared to a controls. In vivo net absorptive flux of glutamine decreased at two weeks but returned toward baseline by eight weeks (P = 0.06). Transport of glutamine into BBMVs was decreased at two weeks and remained decreased at eight weeks. KmaxNa+, a measure of carrier affinity was unchanged but VmaxNa+, a function of the number of transporter was decreased at two and eight weeks. Glucose transport was unchanged. It is concluded that jejunoileal autotransplantation decreases ileal absorption of glutamine by a decrease in carrier-mediated transport of glutamine.

Alanine↗

PubMed1996

Clinical characteristics of acyclovir-resistant herpetic keratitis and experimental studies of isolates.

BACKGROUND: We treated two patients with dendritic keratitis that did not respond to acyclovir (ACV) ointment therapy. Their systemic immune status was normal: however, one patient had a long history of atopic disease and the other had previously undergone topical corticosteroid treatment. HSV-1 was isolated from the patients and inoculated into animals to investigate its viral pathogenicity and latent infection. METHODS: HSV-1 isolates from the patients were tested for drug sensitivity to acyclovir, ganciclovir, idoxuridine, trifluridine, foscarnet and interferon-beta in vitro. In in vivo studies, bilateral corneas of two New Zealand white rabbits and 10 BALB/c mice in each of four groups were infected by the respective viral isolates. The extent of corneal epithelial and/or stromal lesions produced by the viruses was evaluated. The trigeminal ganglial tissues of the mice were examined for viral latent infection by co-culture with Vero cells. RESULTS: Herpetic keratitis in both patients was characterized by prolonged clinical course, succeeded by various types of corneal lesions and ocular complications. In in vitro studies, the two HSV-1 isolates demonstrated cross-resistance to ACV, ganciclovir and/or idoxuridine. Both strains demonstrated weakly virulent corneal epithelial and/or stromal lesions in rabbits and mice. One isolate displayed delayed advent but prolonged course of epithelial lesions in rabbits. The latent infection incidences of the isolates in mice trigeminal ganglia were 6.25% (1/16) and 0% (0/18) respectively. CONCLUSION: Topical immune depression may induce ACV-resistant HSV-1 infection in the cornea, with a prolonged course in association with ocular complications. The prolonged infectious course of the viral isolates in the animal study partially supported the clinical demonstrations in the patient. The existence of latent infection by one ACV-resistant HSV-1 in its animals may indicate the possibility of its recurrence. Trifluridine may be an alternative choice for treating corneal epithelial lesions caused by ACV-resistant HSV-1.

Acyclovir↗

PubMed1996

Modified antigen-binding of human antibodies with glycosylation variations of the light chains produced in sugar-limited human hybridoma cultures.

We have characterized the effects of serum and N-acetylglucosamine in a glucose-deprived condition on the glycosylation of antibody light chains, as well as the resulting biological properties of those antibodies. We have chosen for our investigation the human hybridoma lines producing monoclonal antibodies reactive to lung adenocarcinoma. Each antibody possess a N-glycosylated carbohydrate chain in the hypervariable region of the light chains. When the cell lines were grown in the absence of glucose, variant light chains with varying molecular masses were found to be secreted. Analysis of these light chains produced in a glucose-deprived condition revealed that the changed molecular-mass of the variant light chains is due to different glycosylation. Addition of N-acetylglucosamine or fetal calf serum to the glucose-free medium led to the creation of other light chains that exhibit increased antigen binding activity.

Acetylglucosamine↗

PubMed1996

Adsorption kinetics of bacterial PHB depolymerase on the surface of polyhydroxyalkanoate films.

The kinetics of adsorption and hydrolysis by an extracellular PHB depolymerase from Alcaligenes faecalis were studied at 37 degrees C on the surface of five types of polyhydroxyalkanoate (PHA) films. The films of poly[(R)-3-hydroxybutyrate] (P(3HP)), poly(3-hydroxypropionate) (P(3HP)), and poly(4-hydroxybutyrate)(P(4HB)) were hydrolyzed by the enzyme, while the films of poly[(S)-2-hydroxypropionate)(P(2HP)) and poly(6-hydroxyhexanoate)(P(6HH)) were not eroded. The PHB depolymerase with binding and catalytic domains adsorbed on the surface of all PHA films used, and the adsorption kinetics were found to obey the Langmuir isotherm. The cross-area per one molecule of enzyme binding to the surface of PHA film was estimated to be 17 +/- 8 (nm2/molecule). It has been concluded that the binding domain of enzyme is non-specific for the binding to the surface of PHA film, while the active site in a catalytic domain is specific for the hydrolysis of PHA molecules.

Adsorption↗

PubMed1996

Cell death of oligodendrocytes or demyelination induced by overexpression of proteolipid protein depending on expressed gene dosage.

The transgenic mice, which were produced by introducing the wild type proteolipid protein (PLP) gene, revealed different neurological symptoms depending on expressed gene dosage. Homozygotes, which bore four more copies of the extra PLP gene, died before 4 weeks old with severe tremors and convulsions, while histologically hypomyelination and death of the oligodendrocytes were particularly noticeable. Heterozygotes, which bore two more copies and survived nearly 1 year, suffered from severe hindlimb palsy and bladder-rectal disturbances before death. These symptoms probably resulted from striking demyelination which occurred abruptly at a later stage of life. The heterozygous PLP-transgenic mice are thus available for a model of demyelination diseases.

Animals↗

PubMed1996

AL0671, a new potassium channel opener, inhibits nonenzymatic glycation of protein and LDL oxidation.

1. The effects of AL0671, a novel potassium channel opener, on protein glycation and low-density lipoprotein (LDL) oxidation were tested. 2. AL0671 dose-dependently inhibited both fluorescence development of bovine serum albumin and cross-linking of lysozyme. These inhibitory effects for glycation were no less potent than aminoguanidine. 3. AL0671 dose-dependently inhibited both increase in negative charge and apo B-100 fragmentation during incubation of LDL with Cu2+. In addition, AL0671 significantly decreased the LDL degradation in rat peritoneal macrophages. 4. Neither pinacidil nor levcromakalim inhibited protein glycation and LDL oxidation. 5. Antioxidant properties of AL0671 might be due to its potent electron-donating ability, and this agent is expected to be useful for hypertensive diabetes.

Animals↗

PubMed1996

Visual inputs to cerebellar ventral paraflocculus during ocular following responses.

The activity of cerebellar Purkinje cells was recorded in the ventral paraflocculus (VPFL) of alert monkeys during ocular following responses induced by brief movements of the visual scene. The mossy fiber input evoked 'simple-spikes' which increased their activity during either ipsiversive or downward motion of the visual scene. On the other hand, the 'complex-spikes' evoked by the climbing fiber input increased their activity during either contraversive or upward movement. To further define the sources of the visual input to the VPFL, we recorded single units in the dorsolateral pontine nucleus (DLPN), which is known to project to the VPFL as mossy fibers, and in the pretectal nucleus of the optic tract (NOT), which is known to project to the inferior olive whose neurons project to the cerebellum as climbing fibers. In both areas, most neurons were directionally selective, and responded to the moving visual scene with very short latencies (approximately 40-60 ms). These results suggest that both DLPN and NOT neurons deliver information concerning movements of the visual scene to the VPFL through different pathways.

Animals↗

PubMed1996

Modified N-methyl-D-aspartate receptor subunit expression emerges in reeler Purkinje cells after accomplishment of the adult wild-type expression.

In terms of gene expression for the N-methyl-D-aspartate (NMDA) receptor channel subunits, the adult reeler cerebellum contains two Purkinje cell populations, one expressing the zeta 1 subunit mRNA (wild-type expression) and another expressing the epsilon 1 and zeta 1 subunit mRNAs (modified expression). To clarify development of these two populations, in situ hybridization analysis was performed in the reeler cerebellum from birth to 1 year of age. The epsilon 1 subunit mRNA was not detected in any Purkinje cell clusters (PCCs) until postnatal day 21 (P21). Additional signals for the epsilon 1 subunit mRNA first appeared at P56 in a subset of PCCs, and persisted until 1 year of age. The epsilon 2 and epsilon 4 subunit mRNAs were transiently expressed in PCCs at birth, and disappeared thereafter. No signals for the epsilon 3 subunit mRNA was detected in PCCs at any postnatal stages examined. The zeta 1 subunit mRNA was expressed in all PCCs from birth through 1 year. When compared with the wild-type Purkinje cells, reeler Purkinje cells with modified expression are thus differentiated from those once accomplished the adult wild-type expression (the zeta 1 subunit alone) by down-regulation of the epsilon subunits. The present results further indicate that the onset of the modified expression is subsequent to the establishment of synaptic connectivities in the cerebellum.

Animals↗

PubMed1996

Developmental changes in expression of the ATBF1 transcription factor gene.

The expression of the ATBF1 gene in developing brain was analyzed in mice from 13 days of gestation to 28 days after birth using RNase protection and in situ hybridization methods. The level of ATBF1 transcripts was the highest on embryonic day 13-15 and then progressively decreased to a hardly detectable level on postnatal day 28. Throughout the period examined, ATBF1 mRNA was expressed consistently in the basal telencephalon, diencephalon, and mesencephalon, with the highest levels in the inferior colliculus and thalamus. On the other hand, no significant expression was observed in cerebellum, neocortex, hippocampus, and olfactory bulb. These results illustrate significant regional differences in the ATBF1 expression and suggest a role of the ATBF1 gene in the formation of some specific cell populations in developing central nervous system.

Animals↗