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Biomedical subjects

H Asakura

Publications and source records attributed to H Asakura.

At least 343 records · Page 19Linked to original sources

[An attempt of in vitro portal invasion model of hepatocellular carcinoma utilizing permeable collagen membrane].

Hepatocellular carcinoma (HCC) possessed the ability of vascular invasiveness toward hepatic portal vein on the process of progression. This biological character of HCC can influence the patients survival on clinically. In this paper, we tried to establish the in vitro portal invasion model with human materials. The hepatic portal vein endothelial cell (HPVEC) derived from intrahepatic portal veins by surgically, have been propagated, as outgrowth cultures in RPMI-1640 medium with 10% fetal bovine serum, on permeable collagen membranes (KOKEN, Tokyo) containing mainly type I collagen, covered with a solubilized tissue basement membrane (MATRIGEL, Collaborate Res., Inc., Bedford MA) involving type IV collagen, laminin and proteoglycan. The primary cultured HPVEC with polygonal shaped cells forming a pavement stone sheet, were positively stained with Factor VIII related antigen and synthesized both prostacyclin and collagenase inhibitor. Co-culture of primary human HPVEC and HuH-7 (human HCC cell line obtained from Prof. Satoh, Okayama Univ.,) cells were inoculated onto reverse side between collagen membrane and gell formed basement membrane. Morphological alterations on the side of HPVEC can be obtained such as polylayered cells and different cytoplasmic cells among HPVEC. These results indicate that this experimental model can provide an useful in vitro model for the study of HCC portal invasion.

Carcinoma, Hepatocellular↗

[A case of ankylosing spondylitis complicating Crohn's disease].

A 20-year-old man, who had suffered from ankylosing spondylitis for about 1 year, was admitted to our hospital due to melena and syncope. Physical examination revealed tenderness of abdomen and sacroiliac joint, and decreased spinal mobility. X-ray examination showed sacroiliitis and squaring of vertebral bodies. RA test and RAHA, negative; CRP, strongly positive; HLA-B 27 positive. Intestinal barium enema revealed skipping longitudinal fissure at terminal ileum, and a biopsy specimen of the colon revealed non-caseating granuloma. The association of ankylosing spondylitis and Crohn's disease has widely been known in Europe and United States; but this is the first case reported in detail in Japan, where incidences of both diseases were much lower than those found in Caucasians.

Adult↗

Release of the serum immunosuppressive factor by monocytes in patients with Crohn's disease.

We investigated the in vitro immunosuppressive effect of the sera and the culture supernatants of the peripheral blood mononuclear cells obtained from patients with Crohn's disease. Sera from Crohn's disease markedly suppressed the proliferative response of mouse spleen cells, compared with sera from ulcerative colitis, intestinal tuberculosis and normal controls. The culture supernatants of the adherent mononuclear cells from Crohn's disease showed a remarkable suppressive effect (96 +/- 1%), while the culture supernatants of the non-adherent mononuclear cells had no suppressive activity (-10 +/- 16%). The culture supernatants of the adherent and non-adherent mononuclear cells from normal controls had no suppressive activity. The fractionization of the culture supernatants of the adherent cells from the Crohn's disease patients demonstrated that the fractions with high suppressive activity had similar or identical biochemical properties to the serum immunosuppressive fractions which has been reported previously. These results indicate that monocytes may release the serum immunosuppressive factor in Crohn's disease. This factor may contribute to the depression of the immune reactivity in the mucosal lesion and to the persistence of the stimulation of abnormal immune response in the intestinal wall.

Adolescent↗

Histologic studies on the hepatic lesions induced by graft-versus-host reaction in MHC class II disparate hosts compared with primary biliary cirrhosis.

By light and electron microscopic examinations, histologic changes in the liver of mice with graft-versus-host reaction (GVHR) were analyzed. To induce GVHR, C57BL/6 (B6) spleen cells were injected into (B6Xbm1)F1, (B6Xbm12)F1, and (bm1Xbm12)F1 mice. In (B6Xbm12)F1 recipient mice, bile duct changes resembling chronic non-suppurative destructive cholangitis (CNSDC) and a formation of epithelioid granulomas were observed during the course of GVHR. An epithelioid granuloma in the liver of (B6Xbm1)F1 or (bm1.Xbm12)F1 recipients was not detected. By electron microscopy, the bile duct epithelia were seen to be in close contact with infiltrating cells, and marked alterations of their cytoplasm and microvilli were demonstrated; ie, vacuolation of the cytoplasm, deterioration of microvilli, and bleb formation were frequently observed in the liver of class II-disparate hosts. Concerning the basement membrane, no marked changes characteristic of primary biliary cirrhosis (PBC), such as many-layered basement membranes containing osmium positive substance, were detected. Because the major histocompatibility complex (MHC) class II-disparate system was used in our experimental system in the GVHR, the antigen expressed on the bile duct might be a target and be associated with the formation of the initial hepatic lesions in PBC such as CNSDC and epithelioid granuloma formation. Thus, GVHR across the MHC class II antigen is believed to play an important role in the development of PBC.

Animals↗

Active oxygen species generated by monocytes and polymorphonuclear cells in Crohn's disease.

Chemiluminescence (CL) analysis of monocytes and polymorphonuclear cells (PMNs) was performed on 13 patients with Crohn's disease (CD) and 10 healthy volunteers. The percentages of monocyte populations in mononuclear cells obtained from the patients with CD were greater than those from the healthy volunteers, but the numbers of PMNs were not different between the two groups. The peak level of phorbol myristate acetate (PMA)-induced CL activity generated by diluted whole blood from the patients with CD was more significantly elevated than that from the healthy volunteers, whereas the peak levels of opsonized zymosan-induced CL activity did not differ between the two groups. In monocytes, the peak levels of both PMA- and opsonized zymosan-induced CL activity were significantly higher in the patients with CD than in the healthy volunteers. CL in PMNs, however, showed no significant difference between CD and controls. It is suggested that monocytes of CD have a large capacity to generate active oxygen species. The present study suggests that excessive active oxygen species released by monocytes and perhaps macrophages may play an important role in formation of the intestinal lesions in CD.

Adult↗

Pyloric stenosis in a patient with progressive systemic sclerosis.

A 64-year-old Japanese woman with progressive systemic sclerosis (PSS) who developed severe pyloric stenosis is described. The conservative treatments brought only the temporary symptomatic relief, and pyloroplasty became necessary. No ulcerative lesions or tumors were found in the resected stomach or duodenum specimens implicated for stenosis. The histological examinations revealed edema and replacement fibrosis in the pyloric ring. The possible mechanisms of pyloric stenosis are discussed.

Female↗

Changes in levels of t-PA and alpha 2PI-plasmin complex in plasma in patients with DIC.

Levels of alpha 2PI-plasmin complex and tissue-type plasminogen activator (t-PA) in plasma were determined in 10 cases of acute promyelocytic leukemia (APL) with marked coagulopathy and in 10 cases of hematological malignancies with DIC to investigate relevance to fibrinolysis. In the both groups, levels of alpha 2PI-plasmin complex increased and were inversely proportional to levels of fibrinogen and alpha 2PI. Levels of t-PA in plasma increased moderately in the majority of the both groups. Serial observation of the concentrations of t-PA with corresponding changes in the levels of fibrinogen, alpha 2PI, alpha 2PI-plasmin complex and FDP could not demonstrate any significant relationship between levels of t-PA and the other parameters. From these results, it is unlikely that levels of t-PA in plasma directly influence on the degree of consumption of alpha 2PI or of formation of alpha 2PI-plasmin complex in most cases of DIC.

Anticoagulants↗

T lymphocyte subpopulations and immunoglobulin-containing cells in the colonic mucosa of ulcerative colitis; a morphometric and immunohistochemical study.

T lymphocyte subpopulations and immunoglobulin containing cells in the colonic mucosa of 25 patients with ulcerative colitis have been studied using an indirect immunoperoxidase technique. In ulcerative colitis a marked increase in the population of Leu 3a positive cells (helper/inducer T cells) and IgG containing cells was observed in the mucosal lamina propria. In the intraepithelial spaces, a remarkable decrease in the population of Leu 2a positive cells (suppressor/cytotoxic T cells) and a marked increase in the number of Leu 3a positive cells were revealed. There was a very significant correlation between the population of IgG containing cells and the ratio of Leu 3a positive cells to Leu 2a positive cells in the lamina propria of patients with ulcerative colitis. These results suggest that an imbalance of mucosal immunoregulatory T cells and an increased production of IgG occurred in correlation with inflammatory activities of ulcerative colitis.

Adolescent↗