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H Imaeda

Publications and source records attributed to H Imaeda.

25 records · Page 2Linked to original sources
PubMed1992

Changes in intestinal absorption of nutrients and brush border glycoproteins after total parenteral nutrition in rats.

The effect of total parenteral nutrition on nutrients absorption and glycoprotein changes of brush border membrane was examined in rat small intestine. In total parenteral nutrition rats, a marked decrease in activity of brush border enzymes was observed mainly in the proximal and middle segments of the intestine. Galactose perfusion of jejunal segment showed that hexose absorption was significantly inhibited, while intestinal absorption of glycine or dipeptide, glycylglycine was not significantly affected by total parenteral nutrition treatment. When brush border membrane glycoprotein profile was examined by [3H]-glucosamine or [3H]-fucose incorporation into jejunal loops, significant changes were observed in the glycoprotein pattern of brush border membrane especially in the high molecular weight range over 120 kDa after total parenteral nutrition treatment, suggesting strong dependency of glycoprotein synthesis on luminal substances. Molecular weight of sucrase isomaltase in brush border membrane detected by specific antibody showed no significant difference, however, in total parenteral nutrition and control rats. Also, molecular weight of specific sodium glucose cotransporter of intestinal brush border membrane detected by selective photoaffinity labelling was not altered in total parenteral nutrition rats. It may be that prolonged absence of oral food intake may produce significant biochemical changes in brush border membrane glycoprotein and absorptive capacity of small intestine, but these changes were not observed in all brush border membrane glycoproteins.

Animals↗
PubMed1992

Role of platelet activating factor on the fibrinolytic activation in the pathogenesis of gastric mucosal damage induced by endothelin-1.

We have examined the hypothesis that the release of tissue type plasminogen activator may play a prominent role in endothelin induced gastric mucosal injury. We determined tissue type plasminogen activator activity in the regional blood sample and the concentration of platelet activating factor in the gastric mucosa after the administration of endothelin-1 in a range of 50-500 pmol/kg into the left gastric artery of male Wistar rats. Endothelin-1 increased the tissue type plasminogen activator release and platelet activating factor formation, and induced subsequent gastric mucosal haemorrhagic change in a dose dependent manner. In addition CV-6209, a selective platelet activating factor blocker, attenuated the activation of regional tissue type plasminogen activator and the development of mucosal damage induced by endothelin-1. The results of this study showed that tissue type plasminogen activator activation may play an important role in the pathogenesis of endothelin induced mucosal injury of rat stomach, and suggest that the platelet activating factor may be involved in the process of regional fibrinolytic activation induced by endothelin-1.

Animals↗
PubMed1986

Electron microscopy of Mycobacterium leprae in cutaneous nerve components.

Cutaneous nerves in lepromatous lesions from ninety-six patients were observed by electron microscopy. The regenerative process of myelinated fibers was evident within lepromatous tissues. Intact or degenerative forms of Mycobacterium leprae were surrounded by the electron transparent substance within the axoplasm and Schwann cell cytoplasm. In contrast, the microenvironment of M. leprae in macrophages was characterized with fusing lysosomes and foamy structures. These results suggest that the electron transparent substance may be derived from bacterial metabolites and also that the foamy structure may originate from lysosomal substance.

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PubMedDate not supplied

Significant changes in intestinal lymphatic system and immune response elicited by Peyer's patch excision in adult rats.

The effect of deprivation of Peyer's patches (PP) on transport of lymphocytes through intestinal lymph and intestinal mucosal immune responses was investigated in rats. All visible PP in the rat small intestine were excised in order to examine the roles of PP in the intestinal lymphatic system and mucosal immune responses of the intestine. Two weeks after the experimental excision of PP, lymphocyte transport in intestinal lymph was significantly decreased in PP-excised rats without significant changes in lymphocyte subsets as compared with sham operated control rats. Lymphocyte subsets as determined morphometrically in the intestinal mucosa showed no significant alteration in PP-excised rats. There was a significant decrease in the number of immunoglobulin A (IgA) containing cells in the intestinal mucosa of PP-excised rats, while IgM and IgG containing cells showed no statistically significant changes in number. Conversely, the macrophages in the intestinal mucosa increased in number, suggesting the enhanced accessory functions of these macrophages. Antigen-specific immune response was further studied in PP-excised rats using intraduodenal priming and challenge with cholera toxin (CT). Both the determinations of cells producing antigen-specific antibody in the intestinal mucosa using anti-CT antibody and those of cells secreting anti-CT Ig in the intestinal lymph by enzyme-linked immunospot (ELISPOT) assay showed a significant reduction of CT-specific antibody production in PP-excised rats compared with controls. Peyer's patches appear to have an important role in lymphocyte transportation through intestinal lymph and also in mucosal immune responses.

Animals↗
PubMedDate not supplied

Alteration of mucosal immunity after long-term ingestion of an elemental diet in rats.

The effects of an elemental diet on lymphocyte transport in intestinal lymph and immune responses of gut-associated lymphoid tissue were investigated in rats. The control animals were fed a conventional diet. After 4 week of feeding, the total calorie intake and body weight gain showed no differences between the two groups. The number and total area of Peyer's patches and the ratio of height of villi to height of crypt showed no significant differences between the two groups. The rate of lymph flow in intestinal lymphatics showed no significant change in treated animals compared with the control rats. However, an elemental diet induced a significant decrease in lymphocyte flux in intestinal lymphatics compared with that in control rats. Lymphocyte subsets in intestinal lymph revealed a significant decrease in CD3-positive cells, especially CD4-positive cells in the elemental diet-treated group. A significant decrease in the number of immunoglobulin A-containing cells and a decreased CD4/CD8 ratio in T-cell subsets were observed in the lamina propria of ileal mucosa in the elemental diet-treated group by morphometric analysis in the immunohistochemical study. Specific antibody-secreting cells in intestinal lymph were also investigated after rats were intraduodenally primed with cholera toxin and challenged with the same toxin after an interval of 2 weeks. No significant difference was seen between the two groups in any of the numbers of anti-cholera toxin immunoglobulin-secreting cells in any immunoglobulin A, immunoglobulin G, or immunoglobulin M class as determined by the enzyme-linked immunospot assay.(ABSTRACT TRUNCATED AT 250 WORDS)

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PubMedDate not supplied

A novel treatment for refractory primary biliary cirrhosis?

BACKGROUND/AIMS: Bezafibrate is naturally used for hyperlipidemia worldwide. In 1992 Day et al reported that the value of ALP and gamma-GTP in hyperlipidemia declined after administering bezafibrate orally. We conducted a study to investigate whether or not ALP and gamma-GTP in primary biliary cirrhosis which is characterized by the elevation of these enzymes improved after taking bezafibrate. METHODOLOGY: We administered bezafibrate additionally for 6 months to 13 patients with primary biliary cirrhosis (refractory PBC) whose liver enzymes (ALP or gamma-GTP) did not remain within normal range out of 21 patients treated by monotherapy of ursodeoxycholic acid for 18 months. RESULTS: At 2, 4, and 6 months, gamma-GTP level significantly decreased compared with that prior to the initiation of bezafibrate. At 4 and 6 months, ALP level significantly decreased compared with that prior to the initiation. At 2, 4 and 6 months, ALT level significantly decreased compared with that prior to the initiation. The value of IgG and IgM was also reduced significantly 6 months after the initiation. CONCLUSIONS: If the effectiveness of bezafibrate for primary biliary cirrhosis is confirmed histologically and by a randomized trial, a combination therapy of bezafibrate and ursodeoxycholic acid appear to be the medical treatment of choice for primary biliary cirrhosis in the future.

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