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C Kinoshita

Publications and source records attributed to C Kinoshita.

At least 19 recordsLinked to original sources
PubMed2004

Age-related changes of the ultrastructure in the cardiomyopathic hamster (UM-X7.1 Syrian hamster) parathyroid gland.

We qualitatively and quantitatively investigated parathyroid glands of the UM-X7.1 cardiomyopathic hamster at 1, 2, 6 and 12 months of age to compare them with those of the normal hamster. We found that at 1 month of age in the UM-X7.1 hamster, the Golgi apparatus, lipid droplets and secretory granules decreased. There were no significant differences between the UM-X7.1 hamster and the control hamster at 2 months of age. At 6 months of age, the Golgi apparatus, rER and the secretory granules significantly increased in the UM-X7.1 hamster. At 12 months of age, the Golgi apparatus and lysosomes increased, while the secretory granules decreased. Ultrastructurally, we consider that in the UM-X7.1 hamster, the synthesis and release of the parathyroid at 6 months of age may be activated by an excessive amount of circulating catecholamine, and the functional activity of the parathyroid glands at 12 months of age may be depressed by the increased plasma calcium level. These findings suggest that the activities of the synthesis and release of the parathyroid hormone were the highest at 6 months of age in the UM-X7.1 hamster.

Aging↗
PubMed2001

Histopathologic features of masseter muscle in the distrophic hamster (UM-X7.1 Syrian hamster).

Dystrophic hamster has been regarded as the useful model animal for Severe childhood autosomal recessive muscular dystrophy (SCARMD). Although, many studies on Dystrophic hamster have utilized the muscular tissue of the trunk, however no study have been analyzed for the masticatory muscle. For this study, we used a Dystrophic hamster (UM-X7.1 Syrian hamster) to histochemically investigate the effect of muscular dystrophy on the masseter muscle. Large and small regenerated muscle fibers, and necrotic fibers were detected almost in all areas. Opaque fiber, hypertrophic fiber with fiber splitting structure and necrotic fiber filled up by mononuclear phagocytes were recognized. The region, in which the mononuclear phagocytic cells infiltrated, showed strong positivity to acid phosphatase, and lysosome enzyme. There were many muscle fibers with reduced levels of succinate dehydrogenase (SDH) activities in the muscle fiber. Some TUNEL-positive cells were confirmed in both necrotic and non-necrotic areas. It was suggested that a part of TUNEL-positive cells are the cells originated from the connective tissue or immunocytes. In this result, histopathologic changes of the masseter muscle of the UM-X7.1 Syrian hamster was similar to muscle of the body trunk in the past reports. As the result, it was suggested that jaw closing movements may be negatively affected caused by the decline of the masseter muscle twitch. And, the point of view by which apoptosis is the trigger for the muscle fiber collapse were not seen in the Dystrophic hamster masseter muscle. We suggest that apoptosis is a one step in the process of regeneration of muscle fibers.

Acid Phosphatase↗
PubMed2001

[Not Available].

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Journal Article↗
PubMed1999

Electron microscopic observation on the parathyroid gland of the cardiomyopathic hamster (UM-X7.1 Syrian hamster).

The ultrastructure of the parathyroid gland (PTG) of the UM-X7.1 cardiomyopathic hamster (the UM-X7.1) was qualitatively and quantitatively compared with that of the normal hamster. In the UM-X7.1, the Golgi apparatus and rER were well developed compared with those of the control hamster. Morphometric analysis revealed that the mean values of the Golgi apparatus, rER and large vacuolar bodies were significantly greater in the UM-X7.1 than in the normal hamster and the mean value of lipid droplets was significantly less in the UM-X7.1 than in the normal hamster. Ultrastructurally, we consider that in the UM-X7.1, the synthesis and release of the parathyroid hormone may be activated by an excessive amount of circulating catecholamine, and the functional activity of the PTG may be higher than that in the normal hamster.

Animals↗
PubMed1998

Defective stratum corneum and early neonatal death in mice lacking the gene for transglutaminase 1 (keratinocyte transglutaminase).

The stratum corneum of the skin serves as an effective barrier for maintenance of the internal milieu against the external environment. At the cell periphery of the stratum corneum is the cell envelope, a highly insoluble membranous structure composed of precursor proteins cross-linked by epsilon-(gamma-glutamyl)lysine bonds. Transglutaminase 1 (TGase 1; keratinocyte TGase), a membrane-bound isozyme of the TGase family, has been proposed to catalyze this process of assembly. Deficient cross-linking of the cell envelope in some patients with the autosomal recessive skin disorder lamellar ichthyosis (LI) and several mutations of the TGase 1 gene that have been identified in families with LI suggest the importance of this gene in production of the cell envelope. In this study, we generated mice lacking the TGase 1 gene, and we report that they have erythrodermic skin with abnormal keratinization. In their stratum corneum, degradation of nuclei and keratohyalin F-granules was incomplete and cell envelope assembly was defective. The skin barrier function of TGase 1-null mice was markedly impaired, and these mice died within 4-5 h after birth. These results clearly demonstrate that the TGase 1 gene is essential to the development and maturation of the stratum corneum and to adaptation to the environment after birth. Thus, these TGase 1 knockout mice may be a useful model for severe cases of LI.

Absorption↗
PubMed1998

Effects of low-dose X-irradiation on the development of the mouse cerebellar cortex.

We labeled proliferating cells of the cerebellum of 6-day-old mice with 5-bromo-2'-deoxyuridine (BrdU) followed by a single exposure to 0.5, 1 or 2 Gy of X-rays. We then studied the effects of low-dose irradiation on the migration and survival of granule neurons in the mouse cerebellum. The animals were killed at 4 days, or at 2, 4 or 6 weeks after irradiation. Brains were fixed and BrdU-labeled cells in the cerebella were immunohistochemically analyzed. BrdU was predominantly distributed in the superficial layer of the external granular layer soon after injection. Four days after irradiation with 0.5 or 1 Gy, labeled cells were mainly seen in the inner granular layer, which was also the case in non-irradiated mice. However, following 2 Gy irradiation BrdU was found not only in the inner granular layer, but also in the Purkinje cell layer. This distribution was also seen at 2 and 4-6 weeks after irradiation. In animals irradiated with 1 Gy 4-6 weeks after irradiation, the proportion of labeled cells present in the inner granular layer decreased, while labeled cells in the Purkinje cell layer increased. On the other hand, 0.5 Gy irradiation did not change the distribution of labeled cells, except that the proportion of labeled cells in the inner granular layer decreased at 2 weeks after irradiation. The number of labeled cells in the cerebellar cortex per unit area decreased with time and dose. These results suggest that 2 Gy irradiation induces a migratory delay, abnormal distribution, and cell death of the granule neurons of the mouse cerebellum.

Animals↗
PubMed1997

Short- and long-term effects of low-dose prenatal X-irradiation in mouse cerebral cortex, with special reference to neuronal migration.

To elucidate the short- and long-term effects of ionizing radiation on cell migration in the developing cerebral cortex, we labeled proliferating cells on day 14 of gestation of mice with bromodeoxyuridine (BrdU) followed by a single exposure to 0.1-1 Gy of X-rays. The brains of embryos on day 17 and offspring at 2, 3 and 8 weeks after birth were processed for BrdU immunohistochemistry to trace the movements of BrdU-labeled cells. The location of BrdU-labeled neurons in the cerebral cortex was quantitatively analyzed between irradiated animals and non-irradiated controls. We have demonstrated that the initial migration of BrdU-labeled cells from the matrix cell zone towards the cortical plate during embryonic periods was decelerated when exposed to X-rays of 0.25, 0.5 and 1 Gy on embryonic day 14, and that aberrantly placed neurons in the cerebral neocortex were noted in younger animals that were irradiated prenatally, whereas such derangement was less pronounced in mature animals. These observations suggest that some modification process might have occurred during the postnatal period.

Animals↗
PubMed1997

Effects of continuous low-dose prenatal irradiation on neuronal migration in mouse cerebral cortex.

We investigated the effects of continuous exposure to gamma-rays during corticogenesis on the migration of neuronal cells in developing cerebral cortex. Pregnant mice were injected with 0.5 mg of bromodeoxyuridine (BrdU) on day 14 of gestation to label cells in the S phase. The mice were then exposed to 137Cs gamma-rays (dose rates of 0.1, 0.3, and 0.94 Gy/day) continuously for 3 days. Brains from 17-day-old embryos and from offspring at 3 and 8 weeks after birth were processed immunohistochemically to track the movements of BrdU-labeled cells. Comparative analyses of the distribution pattern of BrdU-labeled cells in the cerebral cortex revealed that (1) the migration of neurons was delayed during the embryonic period in mice irradiated at 0.94 Gy/day, (2) in 3-week-old mice, there was a significant difference in the distribution pattern of BrdU-labeled cells in the cerebral cortex between the mice irradiated prenatally and control, and (3) in 8-week-old mice, there were no differences in the distribution pattern of BrdU-labeled cells between control and animals irradiated with 0.1 and 0.3 Gy/day. In contrast, in the animals irradiated with 0.94 Gy/day, the significant difference in the distribution pattern of the labeled cells relative to control was maintained. These results suggest that the migration of neuronal cells in mouse cerebral cortex is disturbed by continuous prenatal irradiation at low-dose and some modificational process occurred during the postnatal period.

Animals↗
PubMed1996

Effects of age on levels of cysteine, glutathione and related enzyme activities in livers of mice and rats and an attempt to replenish hepatic glutathione level of mouse with cysteine derivatives.

There was a large statistically significant decrease in the hepatic level of cysteine and glutathione (GSH) in 24 month-old mice compared to young mice, while, cystine and glutathione disulfide (GSSG) contents in the liver did not differ between young and old mice. Activities of cystathionine gamma-lyase and beta-synthase in mouse liver of the 24 month-old group were significantly decreased. In rats, the hepatic levels of cysteine, cystine, GSH and GSSG exhibited no statistically significant change during aging to 30 month. As the rats matured, total hepatic activities of both cystathionine gamma-lyase and beta-synthase increased with maximum levels at 24 months of age and decreased to the same level found in 5 week old for the former and to 22% of that in 5 week old for the latter. Intraperitoneal administration of diethyl maleate to mice led to depletion of hepatic GSH. When N-acetylcysteine and a thiazolidine derivative were intravenously injected after diethyl maleate administration, the hepatic GSH level of mice was restored to the normal level.

Acetylcysteine↗
PubMed1996

A combined staining method for argyrophilic nucleolar organizer regions and for glial fibrillary acidic protein in astrocytes of human brain.

Different protocols are described for the combined staining method by which argyrophilic nucleolar organizer region sites can be evaluated in human astrocytes that are immunoreactive for glial fibrillary acidic protein. Among the four protocols studied, the following method was superior to others in terms of unambiguous visualization of the regions in glial fibrillary acidic protein-positive astrocytes; the first step was immunostaining for the protein with a blue colour reaction of alkaline phosphatase, followed by sequential colloidal silver staining for the regions. By this double staining method, we have demonstrated that the reactive astrocytes found in white matter around the metastatic lesion of carcinoma and the infarction, contain more argyrophilic nucleolar organizer regions in terms of the count as well as the area than glial fibrillary acidic protein-positive astrocytes present in the white matter of the normal brain. In conclusion, the double staining may provide valuable information on the cellular activity of astroglia when performed on routine formalin-fixed paraffin sections of the human brain.

Astrocytes↗
PubMed1996

Genotypes and alkaloid contents of Datura metel varieties.

Datura metel L. var. muricata (BERNH.) DANERT was found to be double recessive with respect to the genes concerning the color and form of the corolla by breeding experiments involving four varieties, i.e. var. metel (white, simple corolla), var. rubra (purple, simple), var. fastuosa (purple, double or triple) and var. muricata (white, purple). The results support the proposal by Danert and others that these variants should be considered as varieties or forms of a single species, Datura metel. The analysis of tropane alkaloids in the seeds, flowers, and leaves of these four varieties showed that scopolamine was always dominant over hyoscyamine. The range of the scopolamine content (% of dry weight) of seeds, flowers, and leaves was 0.294 (var. rubra)-0.631 (var. fastuosa), 0.190 (var. metel)-0.698 (var. rubra), and 0.042 (var. rubra)-0.255 (var.metel), respectively. These findings proved that all the varieties, including var. muricata, which exhibited medium scopolamine content among the varieties, can be utilized as sources of scopolamine.

Atropine↗
PubMed1996

A simplified method for the estimation of glutathione peroxidase activity and selenium concentration in bovine blood.

Twelve hybridoma clones were established that produced mouse monoclonal antibodies to bovine erythrocyte glutathione peroxidase. In these monoclonal antibodies, GPF-1, GPI-2, and GPJ-1, which showed marked reaction to this enzyme, were examined for reactivity to erythrocyte lysates from 12 different species of animals and from humans and for the inhibition of glutathione peroxidase activity. GPF-1 and GPJ-1 reacted markedly with glutathione peroxidase in erythrocyte lysates from ruminants and pigs and inhibited enzymatic activity. Conversely, GPI-2 showed positive reaction to hemolysate from all mammals used, except for mice, and did not inhibit enzymatic activity. To determine the concentration of bovine glutathione peroxidase in erythrocyte lysates, a sandwich ELISA was developed using GPJ-1, both as a coated antibody and as a peroxidase-labeled antibody. This ELISA system was a sensitive procedure with a detection limit of 6 ng/ml for glutathione peroxidase protein. Using blood samples from 121 cows, optical density by this ELISA was well correlated with the glutathione peroxidase activity and with the selenium concentration in bovine whole blood. The sandwich ELISA using GPJ-1 is a rapid and simple screening method to estimate glutathione peroxidase activity and selenium concentration in bovine whole blood.

Animals↗
PubMed1994

Effect of passive immunization with serotype-specific monoclonal antibodies on Actinobacillus pleuropneumoniae infection of mice.

Specific monoclonal antibodies (MoAbs) to Actinobacillus pleuropneumoniae (APP) serotypes 1 and 2 which recognized serotype-specific antigens were produced. It was revealed that the two serotype-specific MoAbs H1-18 and H22-7 recognized O polysaccharides of the lipopolysaccharide (LPS) from APP serotypes 1 and 2, respectively, in the results of antigen analysis by means of SDS-PAGE and Western blotting. Furthermore, ddY mice immunized passively with the above type-specific MoAbs were protected against challenge infection by the homologous serotype of APP at 24 or 48 hr later. However, H1-9 and H3-2 MoAbs recognizing serotype-common protein antigens of APP did not show signs of any protective effect. These results showed that LPS from APP bacterial cells was one of the structural substances in the serotype-specific antigens, and an important component as one of the antigens protecting against the homologous serotype strain.

Actinobacillus Infections↗
PubMed1994

Insulin response to glucose-6-phosphate dehydrogenase activity is elevated in rats fed diets low in polyunsaturated fatty acids.

Glucose-6-phosphate dehydrogenase (G6PD) activity in the rat liver was elevated when the animals were fed a diet that contained 5% coconut oil or 1% corn oil plus 4% palmitic acid, in comparison with that of rats fed 5% corn oil. G6PD activity correlated inversely with the PUFA/SFA ratio of total liver phospholipid as well as the ratio of plasma membrane phospholipid. Elevation of G6PD activity was slightly affected by dietary protein. Serum insulin levels were apparently not influenced by dietary fats, and were not correlated with G6PD activity. Insulin dose-response to G6PD activity was augmented in primary cultured hepatocytes isolated from rats fed a diet with 1% corn oil plus 4% palmitic acid in comparison with those fed a diet with 1% corn oil plus 4% palmitic acid in comparison with those fed a diet with 5% corn oil. These findings indicate that augment in insulin dose-response to G6PD and elevation of its activity shown in rats fed diets low in polyunsaturated fatty acid are associated with lowering the PUFA/SFA ratio in plasma membrane phospholipid.

Animals↗
PubMed1993

Basic fibroblast growth factor promotes adhesive interactions of neuroepithelial cells from chick neural tube with extracellular matrix proteins in culture.

Fibroblast growth factors have been increasingly assigned mitogenic and trophic roles in embryonic and postnatal development of the nervous system. Little is known, however, of their functional roles in early embryonic neural development at the neural tube stage. We have examined the effect of basic fibroblast growth factor (bFGF) on the adhesive behavior in culture of dissociated brachio-thoracic neural tube cells from 26- to 30-somite stage chick embryos. Cells plated on collagen-coated substratum at a low density attach to the substratum but show poor cell spreading. Addition of bFGF markedly promotes cell spreading, yielding an epithelial morphology. This effect becomes discernible 6-8 hours after cell plating with bFGF and is completed by 24 hours, with half-maximal and maximal effects attained at around 0.4 and 10 ng/ml, respectively. The number of cells remain largely constant up to 24 hours, and then cell survival and/or mitogenic effects of bFGF become apparent. The cell spreading effect is abolished by cycloheximide treatment, inhibited by the anti-beta 1-integrin antibody CSAT, and accompanied by about twofold increases in the expression of beta 1-integrin and vinculin, components of focal adhesion complexes. Cells cultured with bFGF for 24 hours exhibit enhanced cell attachment and cell spreading with little time lag following cell plating. In earlier embryonic stages, developmentally less mature cells depend much more on bFGF for their cell spreading and survival, while in later stages the cell spreading response to bFGF becomes undetectable as neural tube develops to spinal cord. The cell spreading effect of bFGF is realized on specific extracellular matrix proteins including laminin, fibronectin and collagen, but not on vitronectin, arg-gly-asp peptide (PepTite-2000), poly-L-ornithine or others. These results suggest that, in an early stage of neural tube development, bFGF is involved in the developmental regulation of adhesive interactions between neuroepithelial cells and the extracellular matrix, thereby controlling their proliferation, migration and differentiation.

Animals↗
PubMed1990

Experimental intraocular lens implantation in the rabbit eye and in the mouse peritoneal space. Part V: Phagocytosis and nuclear patterns of giant cells observed on the implanted lens surface.

The major cellular components on intraocular lenses experimentally implanted in the rabbit eye and in the mouse peritoneal space were examined. They consisted of macrophages and their metamorphosed epithelioid cells with occasional formations of foreign-body giant cells from the fusion of the macrophage-related cells. Lymphocytes, individually and in clusters, were also seen on the lenses implanted in the mouse peritoneal space but rarely on those implanted in the rabbit eye. Macrophages, epithelioid cells, and giant cells exhibited active phagocytosis on the implanted intraocular lenses. These cells phagocytized not only minor foreign particles such as artificially fed latex or carbon colloids but also living cells including erythrocytes, leukocytes, and lymphocytes. The nuclear pattern of the giant cell formation process initially assumed a centrally located nuclear distribution of a foreign-body giant cell type, and then a peripherally located Langhans type distribution when the number of nuclei reached about five in both the mouse peritoneal space and the rabbit eye chamber. Ultra-large giant cells containing a number of nuclei, however, were only observed on lenses implanted in the rabbit eye, demonstrating a difference between the two environments.

Animals↗
PubMed1990

Comparison of the cellular response on intraocular lenses implanted in rabbit eyes with and without extracapsular lens extraction.

Three-piece poly(methyl methacrylate) intraocular lenses (IOLs) were implanted in rabbit eyes with and without lens extraction to examine the cellular response on the IOL surface without the effects of the residual lens cortex. Each rabbit had extracapsular lens extraction (ECCE) with IOL implantation in the posterior chamber of one eye. In the second eye, the IOL was implanted in the anterior chamber without lens extraction. The lenses were removed and studied with light microscopy and scanning electron microscopy one week after surgery. Light microscopic findings revealed a similar cellular response on the surface of the IOLs in both groups. Scanning electron microscopy suggested that the cellular adhesiveness on the IOL surface in the eyes without lens extraction was weaker than in the eyes that had ECCE. Cells on the IOLs in the eyes without lens extraction were flatter and had membranous pseudopodia. It appears that the cells on the IOL surface were caused by a foreign body reaction and that their adhesiveness to the IOL was affected by residual lens cortex.

Animals↗