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Y Kodaira

Publications and source records attributed to Y Kodaira.

At least 19 recordsLinked to original sources
PubMed2006

Effect of palate covering on bolus-propulsion time and its contributory factors.

The aim of this study was first to investigate whether the covering of the palatal mucosa with a denture base affects or not the bolus-propulsion time, and second if there was such an effect then investigate the possible contributory factors which have influence on the propulsion time. The propulsion time was measured in 21 young normal edentulous subjects under five different conditions: a complete palatal covering, non-covered palate, anterior palatal covering, posterior palatal covering and surface anaesthetized palate. As possible contributory factors palatal morphometric parameters, as well as tongue pressure were also measured. The data were analysed on the following way: changes when the palate was complete covered and non-covered, effects of sensation reduction after topic anaesthesia, effects of differences in the covering site, effects of palatal morphometric parameters and effects of tongue pressure. Ten subjects exhibited significant differences in the propulsion time when comparing the data between the complete palatal covering and the non-covered palate condition (change group). Eleven subjects did not show changes (unchanged group). Effects in the propulsion time were also recognized with posterior palatal covering-palate and superficially anaesthetized palate. With regard to the tongue pressure, significant differences during swallowing were observed. These results indicated that the bolus propulsion time into the oropharynx was affected by the palatal covering in some subjects. Moreover, the sensation in the posterior region of the hard palate, as well as the tongue pressure were also factors which affected the propulsion time during swallowing.

Adult↗
PubMed2000

Phenotypic and functional maturation of dendritic cells mediated by heparan sulfate.

Primary immune responses are thought to be induced by dendritic cells. To promote such responses, dendritic cells must be activated by exogenous agonists, such as LPS, or by products of activated leukocytes, such as TNF-alpha and IL-1. How dendritic cells might be activated in the absence of exogenous stimuli, or without the immediate presence of activated leukocytes, as might occur in immunity to tumor cells or transplants, is unknown. We postulated that heparan sulfate, an acidic, biologically active polysaccharide associated with cell membranes and extracellular matrices, which is rapidly released under conditions of inflammation and tissue damage, might provide such a stimulus. Incubation of immature murine dendritic cells with heparan sulfate induced phenotypic maturation evidenced by up-regulation of I-A, CD40, CD54 (ICAM-1), CD80 (B7-1), and CD86 (B7-2). Dendritic cells exposed to heparan sulfate exhibited a markedly lowered rate of Ag uptake and increased allostimulatory capacity. Stimulation of dendritic cells with heparan sulfate induced release of TNF-alpha, IL-1beta, and IL-6, although the maturation of dendritic cells was independent of these cytokines. These results suggest that soluble heparan sulfate chains, as products of the degradation of heparan sulfate proteoglycan, might induce maturation of dendritic cells without exogenous stimuli, thus contributing to the generation and maintenance of primary immune responses.

Animals↗
PubMed1998

Role of the liver in T cell differentiation--generation of CD3-CD4+/CD8+TCRbeta- cells and CD3-4-8-TCRbeta+ cells from CD4-8-TCRbeta- athymic nude bone marrow cells by culture with parenchymal liver cells.

To investigate the influence of the liver on differentiation of hematopoietic stem cells/pro-T cells, TN-NWP-BMC (athymic nude bone marrow cells that were treated with anti-TCRbeta, anti-CD4, and anti-CD8 Abs plus complement and then passed through a nylon wool column) were cultured on parenchymal liver cells. After culture for 2.5 days, CD3-4-8-TCRbeta+ cells and CD3-CD4+/CD8+TCRbeta- cells were developed from TN-NWP-BMC. TCRVbeta8+ cells comprised 19.9% of CD3-4-8-TCRbeta+ cells, and Vbeta8 mRNA was detected in the CD3-4-8-TCRbeta+ cells by reverse transcriptase-polymerase chain reaction. The CD3-CD4+/CD8+TCRbeta- cells contained not only single-positive cells but also CD4+8+ double-positive cells. The CD8 protein consisted of 88.9% CD8alpha+beta-, 10.1% CD8alpha+beta+, and 1% CD8alpha-beta+ molecules. From these results and the finding of co-expressed antigens, CD3-4-8-TCRbeta+ cells and CD3-CD4+/CD8+TCRbeta- cells appear to be immature cells not committed to a certain cell lineage.

Animals↗
PubMed1997

Primary aortoduodenal fistula caused by duodenal tuberculosis without an abdominal aortic aneurysm: report of a case.

A 66-year-old man died of massive gastrointestinal hemorrhage caused by a fistula between the third portion of the duodenum and the abdominal aorta. An autopsy revealed that duodenal tuberculosis had resulted in the development of a fistula into the aorta with no pathological changes, and no active pulmonary tuberculosis was found. Duodenal tuberculosis and primary aortoduodenal fistula (ADF) without an aneurysm are both extremely rare. Thus, we report herein a unique case of primary aortoduodenal fistula without an abdominal aortic aneurysm, but associated with duodenal tuberculosis, and review the current literature.

Aged↗
PubMed1996

Interleukin 7 receptor-deficient mice lack gammadelta T cells.

The interleukin 7 receptor (IL-7R) plays a crucial role in early B- and T-cell development. It consists of a unique a chain and a common gamma chain [IL-2 receptor gamma chain (IL-2Rgamma)]. Gene inactivation of IL-7, IL-7R, and IL-2Rgamma resulted in severe impairment of B and T lymphopoiesis in mice. In addition, IL-2Rgamma-deficient mice lack gammadelta T cells in the skin and have the impaired development of natural killer (NK) cells and intraepithelial lymphocytes. To explore the role of IL-7/IL-7R system in gammadelta T- and NK-cell development, we have generated and analyzed IL-7R-deficient mice. gammadelta T cells were absent from skin, gut, liver, and spleen in the deficient mice. In contrast, alphabeta T and B cells were detected in reduced, but certain, numbers, and NK cells developed normally. The gammadelta T-cell development in fetal and adult thymus was also completely blocked. These results clearly demonstrate that the signal from IL-7R is indispensable for gammadelta T-cell development in both thymic and extrathymic pathways. On the contrary, it is suggested that NK-cell development requires cytokine(s) other than IL-7.

Animals↗
PubMed1996

Developmental heterogeneity of V gamma 1.1 T cells in the mouse liver.

Modifications at V-(D)-J junctions increase the diversity of T-cell receptors (TCR). It has been shown that the levels of N-nucleotide insertion at the V-(D)-J junction in TCR transcripts are different between fetal and adult stages. To clarify developmental stages and pathways of gamma delta T cells in the liver, we analysed the nucleotide sequence of V gamma 1.1-J gamma 4 junctions of intra-hepatic lymphocytes (IHL), spleen cells and developing thymocytes from normal and athymic nude mice. The level of N-insertion increased in thymocytes during ontogeny. The percentage of V gamma 1.1-J gamma 4 transcripts with N-insertion was 3% at day 16 of gestation, 42% at newborn, and 89% at 7 weeks. Transcripts from normal IHL showed intermediate levels of N-insertion between those of newborn and adult thymocytes. In contrast the percentage of N-insertion in nude IHL was 47%, and this value was comparable to that of newborn thymocytes. Among the transcripts of normal IHL, the sequences common with nude IHL showed a newborn level of N-insertion (38%), and the remaining sequences showed an adult level (89%). These results suggested the possibility that V gamma 1.1-expressing T cells in IHL might be a heterogeneous population consisting of the cells developed extrathymically as well as the cells developed intrathymically. The V gamma 1.1-J gamma 4 junctions from spleen cells showed less variability than those from IHL and adult thymocytes. It suggested that gamma delta T cells bearing specific V gamma 1.1 TCR develop and/or home in the spleen.

Age Factors↗
PubMed1979

Effects of acute starvation on carbohydrate metabolism in rat salivary glands.

1. Effects of acute starvation on enzymes of carbohydrate metabolism were determined in rat submandibular and parotid glands. 2. Activities of glycolytic enzymes were high in submandibular gland, but those of pentose phosphate pathway and glycogen metabolism were high in parotid gland. 3. Enzyme activities were lowered by acute starvation. Refeeding the rats with solid diet restored the enzyme activities, but with liquid diet, only partial recoveries were found in submandibular gland.

Animals↗