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Biomedical subjects

N Shinomiya

Publications and source records attributed to N Shinomiya.

At least 73 records · Page 4Linked to original sources
PubMed1990

Differential function of polymorphonuclear leukocytes between in vivo and in vitro in tumor-bearing mice.

In the present report, we compared activities of polymorphonuclear leukocytes (PMN) such as phagocytosis and bactericidal activity in vivo with those in vitro in sarcoma 180 (S 180)-bearing mice. Mice showed a remarkable leukocytosis and in increase in PMN fraction of peripheral blood leukocytes (PBL) after intraperitoneal injection of S 180 cells. Tumor-bearing mice infected with Escherichia coli (E. coli) intravenously and intraperitoneally showed an apparent delay in the clearance of bacteria compared to the non-tumor-bearing control mice. However, PBL of tumor-bearing mice showed a high phagocytic activity against beads and a high chemiluminescence (CL) activity. Dichlorofluorescein (DCFH) oxidation capacity of peripheral blood PMN in S 180-bearing mice after stimulation with phorbol myristate acetate (PMA) was about the same or a little stronger than that in control mice. On the contrary, serum and ascites of tumor-bearing mice strongly suppressed the phagocytic and bactericidal activities of casein-induced PMN against E. coli. During the early phase of E. coli infection, serum level of complement (C3) was not depressed in tumor-bearing hosts. From these results, it is concluded that leukocytosis and activation of functions of PMN in tumor-bearing mice were observed in vitro but they were not effective for the protection in the early phase of actual E. coli infection in vivo. The delay of in vivo clearance may be accounted for by a suppressive effect of serum components in tumor-bearing mice.

Animals↗
PubMed1989

The role of T cells in immunoglobulin class switching of specific antibody production system in vitro in humans.

Only antibodies of the IgM class were produced in vitro by peripheral blood mononuclear cells stimulated with streptococcal carbohydrate. B cells of the peripheral blood mononuclear cells, however, synthesized both IgM and IgG class antibodies when combined with tonsillar T cells, suggesting that T cells inducing immunoglobulin class switching are present in the tonsils. Peripheral blood T cells also became capable of inducing B cells to produce IgG class antibodies when the T cells were incubated with antigen-pulsed macrophages. Surface IgM-positive, IgG-negative high-density B cells produced IgG antibodies for streptococcal carbohydrate in the presence of these T cells or tonsillar T cells. The culture supernatant solutions from these T cells or tonsillar T cells, however, failed to cause the B cells to produce IgG, indicating that class switching is not mediated by factors released from T cells. Lymphokines such as interleukin-2, human B cell growth factor, helper T cell factor, or interferon-gamma were also incapable of inducing IgG production. These results suggest that the cognate interaction between T cells and B cells is necessary for the immunoglobulin class switching.

Antibodies, Bacterial↗
PubMed1989

[Basic study of chemo-embolization of the liver using hydroxyapatite granules].

The purpose of this study was to elucidate the availability of hydroxyapatite (HAp) granules as a chemoembolic agent in chemo embolization therapy. A mixture of adriamycin (ADM) and an embolic agent (HAp, Lipiodol) was injected via hepatic artery in normal Wistar rats. Then the concentration of ADM in the liver serum transaminase level were measured serially. The remaining ADM in the liver was higher in groups with HAp granules than the others. The serum transaminase, however, were lower in the HAp groups. There are some advantages of HAp using as a chemo embolic agent. (1) HAp is a physiological biomaterial and seem to be safe for human. (2) HAp granules injected into the liver are easily detectable by X ray and ultrasonography. (3) HAp granules have a large surface area and this characteristic is suitable for a carrier of drugs. It is concluded that HAp granules have some necessary prerequisites for a chemo embolic agent and the application to clinical practice may be expected.

Animals↗
PubMed1988

Inhibition of tumor growth by dairy products.

Effects of dairy products (cheeses and yoghurt) on growth of transplanted murine tumors were examined in various tumor-host combinations. Suppression of tumor growth was observed in proportion to the duration of feeding. Peripheral lymph-node (LN) cells of mice fed dairy products showed an increment in the fluorescence intensity of Thy-1.2+ cells in FACS analysis. These cells showed an augmented PHA response and a remarkable antitumor effect in tumor neutralization test (Winn's assay) compared to control lymphocytes. These results suggest that dairy products enhance the activity of peripheral LN cells to suppress the tumor growth. Moreover, serum transfer from cheese fed mice revealed the protective effects against tumors, while that from yoghurt fed mice did not show such an effect. In the former mice, serum iron level was increased compared to control levels but antibody response to sheep erythrocytes (SRBC) was not augmented. From these results, we propose a hypothesis that lymphocytes may be activated by transferable serum factors such as iron-saturated transferrin and suppression of tumor growth caused by the effector-target interaction which is mediated by effector-associated transferrin in the case of cheese fed mice. In yoghurt fed mice another mechanism is suspected because of the low level of serum iron.

Animals↗
PubMed1988

Effect of a high-fat diet on resistance to Listeria monocytogenes.

Effects of a high-fat diet on macrophage (M phi) functions were investigated. Eight-week-old ddN mice were fed a high-fat diet and carbon clearance was tested. Remarkable suppression of phagocytic activity (K16) was observed in mice fed such a diet for 1 or 2 weeks. Resistance against Listeria monocytogenes inoculated intravenously (iv) with a lethal, a sublethal, or a non-pathogenic dose was observed in the liver of mice fed a high-fat diet. When mice were infected with a lethal dose of bacteria, the number of listeria increased progressively in the liver to kill both control and a high-fat diet fed mice by day 4. The number of listeria revealed no significant difference between the group in the case of low dose inoculation. High-fat diet fed mice given a sublethal dose of bacteria showed a rise in the number of viable bacteria during the first 3 days after infection while a decline in the number of bacteria was observed in control mice during such a period. Suppression of M phi activity induced by a high-fat diet may account for the reduced resistance.

Animals↗
PubMed1987

Cholera toxin-induced tolerance to allografts in mice.

When C3H/HeN (C3H) mice were primed with viable C57BL/6 (B6) spleen cells and treated with cholera toxin (CT) on the same day, a profound tolerance to tumour allografts of B6 origin was induced. The tolerant state was sustained for as long as 6 weeks or more. Skin allografts of B6 were rejected by such tolerant C3H mice, although the survival times were prolonged very slightly. Generation of cytotoxic T lymphocytes was reduced markedly in the tolerant mice, whereas delayed footpad reaction to B6 cells was maintained at the normal immune level or higher. There is a possibility that a T-cell subset responsible for delayed footpad reaction is resistant to CT-induced tolerance and participates in the rejection of skin allografts in tolerant mice.

Animals↗
PubMed1986

Immune protective mechanisms during pregnancy. I. Cell-mediated immunity against Listeria monocytogenes in pregnant mice.

Characteristics of protective mechanisms during pregnancy were investigated using neonatally thymectomized (NTx) and/or pregnant mice infected with sublethal doses of Listeria monocytogenes, of which the explosive growth at an early phase of 2 or 3 days after infection is prevented by non-immune macrophages, and complete elimination at a late phase from 4 to 10 days after infection is attributed to the augmented functions of macrophages in co-operation with lymphokine-producing sensitized T lymphocytes. Although in virgin control mice there was a gradual decline of bacteria from the day after infection, viable bacteria in pregnant mice showed an increase in number until Day 3. In such pregnant mice, carbon clearance was suppressed. Thus, the enhanced bacterial growth in pregnant mice within 3 days may be attributable to the suppressed functions of non-immune macrophages. Complete elimination of Listeria from Day 4 was observed in pregnant sham-operated mice as well as in non-pregnant and pregnant NTx mice. Twenty-four hour reaction of delayed-type in normal mice induced by sheep red blood cells (SRBC) in incomplete Freund's adjuvant (IFA) was not affected by pregnancy, while 48 hr reaction in mice immunized with SRBC in complete Freund's adjuvant (CFA) was suppressed by pregnancy. We have reported previously that macrophage migration inhibitory factor (MIF) was produced in the latter but not in the former, and that the tuberculin type of delayed hypersensitivity accompanied by MIF production scarcely participated in acquired resistance to Listeria. Effective elimination of Listeria in pregnant and/or NTx mice at a late phase may be attributable to the activity of cellular immunity comparable to 24 hr reaction. These results suggest that T cells showing a low degree of thymus dependency in the ontogenic development may be the major component required for acquired protective immunity against Listeria and may account for the protection in pregnant mice.

Animals↗
PubMed1985

Effects of neurosurgical treatment on diffuse slow spike and wave complex: a case of left frontal mass lesion with diffuse slow spike and wave complex (DSSW).

A 10-year-old girl with a mass lesion in the left deep frontal lobe was reported. Clinically, seizures occurred at 3 years and 8 months and became intractable around the age of 5.5 years. EEG initially showed focal spikes on the left fronto-central area and later developed into diffuse slow spike and wave complexes (DSSW). Her seizures were clinically different from those in Lennox-Gastaut syndrome. After a left frontal lobectomy, her intractable seizures completely disappeared with marked EEG improvement and without any neurological deficit. Radiological findings before the operation suggested that the expanding effects extended to the deep temporal structures, adjacent to the frontal lobe. These structures, deep frontal and temporal lobes, both or either, were assumed to be involved in generating DSSW in this case.

Child↗
PubMed1985

[Augmentation of resistance against metastatic tumor cells after local administration of PSK].

Local administration of PSK augmented the generation of cytotoxic lymphocytes and the induction of resistance against metastatic tumor. Augmented generation of cytotoxic lymphocytes may be ascribed to local effects of PSK in the lymph nodes, since this is mediated by Lyt-1+2+ cells. Local administration of PSK increased the threshold number of metastatic tumors eliminated by hosts. This finding seems to be important in relation to augmentation of resistance against metastasis or local implantation with a limited number of tumor cells.

Adjuvants, Immunologic↗
PubMed1985

In-vitro analysis of defective IgA production in selective IgA deficiency in childhood.

IgA production from B cells can be driven by three signals (anti-Ig antibody, B cell growth factor and helper T cell factor). It was thought that this three signal system might be a way other than the mitogen-stimulated system, to access B cell differentiation into Ig-producing cells. Seven children with IgA deficiency were investigated by this method. In all cases B cell differentiation was defective when using this three signal system. In one case, IgA producing cells were generated in normal number from B cells when stimulated with pokeweed mitogen in the presence of normal T cells. Definite abnormality of regulatory T cells in the IgA production was observed in only one case. These observations suggested that the main cause of IgA deficiency in most cases is the defect of B cells to differentiate into IgA secreting cells.

B-Lymphocytes↗