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Biomedical subjects

M Kikuchi

Publications and source records attributed to M Kikuchi.

At least 991 records · Page 55Linked to original sources
PubMed1985

The influence of phase shift in the light-dark cycle on humoral immune responses of mice to sheep red blood cells and polyvinylpyrrolidone.

The influence of a phase shift in the light-dark cycle on humoral immune responses against sheep red blood cells (SRBC), a thymus-dependent antigen, and against polyvinylpyrrolidone (PVP), a thymus-independent antigen, was studied by using 180 BALB/c mice and 150 C3H/HeN mice. Significant suppression of the immune response to SRBC and the number of splenic plaque-forming cells (PFC) and hemagglutination (HA) titers was observed on days 5 and 6 after inversion of the light-dark cycle. On the other hand, the number of splenic PFC and HA titers in the blood against PVP were minimally suppressed by the phase shift in C3H/HeN mice, except for distortion of the rhythmicity. Corticosterone levels in the blood on days 5 and 6 after inversion were higher than those under a normal lighting regimen. The appearance of the high corticosterone level in the blood after the inversion almost concurred with the suppression of the immune response to SRBC. A decrease of the proportion of splenic T cells was also observed on day 6 after the inversion. These results show that a phase shift in the light-dark cycle provokes suppression of the immune response to SRBC, possibly through an increase of secretion of corticosterone after light-dark inversion, which induces a decrease of the proportion of T lymphocytes in the spleen.

Animals↗
PubMed1985

[Malignant lymphoma of Waldeyer's ring: is lymphography always necessary?].

The role of lymphography for patients with malignant lymphomas involving Waldeyer's ring was retrospectively reviewed. The materials were 97 patients who were treated at Kyushu University Hospital from January, 1966 to December 1982. Lymphography was performed in 72 patients. Abnormal retroperitoneal nodes were detected only in 13 of them (18%). Six of the 7 patients (86%) with gastrointestinal involvement as well as Waldeyer's ring had positive lymphography, whereas only 6 of the 51 patients (12%) without gastrointestinal involvement had such findings. Although there was a significant difference in survival by cervical and inguinal lymph node status, no such discrepancy was seen between 41 stage II patients staged after lymphography and 16 stage II patients staged clinically. All these results suggest that lymphography is not always essential for patients with malignant lymphomas involving Waldeyer's ring.

Adolescent↗
PubMed1985

Delayed type hypersensitivity (DTH) skin reaction to hepatitis B surface antigen (HBsAg) in patients with type B acute and chronic hepatitis.

Skin reactivity to HBsAg was studied in patients with type B acute and chronic hepatitis and in healthy controls. HBsAg preparations containing 50 micrograms/ml of antigen both with and without alum elicited positive skin reactions in all seven anti-HBs+ persons. Histological examination of skin tissue from the reactive area using monoclonal antibodies to the cell surface of lymphocytes revealed accumulation of Leu-3a positive lymphocytes, showing that the inflammation was a typical delayed type hypersensitivity (DTH) reaction. Irrespective of the presence of HBeAg and anti-HBe, patients with chronic type B hepatitis responded clearly to PPD and SK/SD antigens, whereas they did not exhibit DTH skin reactivity to HBsAg. In contrast, although patients with acute type B hepatitis did not exhibit specific DTH a reaction to HBsAg in the acute period, they began to develop DTH skin reactivity to HBsAg in the convalescent phase of the disease preceding the appearance of anti-HBs antibody. It is suggested that DTH reaction to HBsAg might play an important role in the pathogenesis of type B viral hepatitis.

Acute Disease↗
PubMed1984

The organ distribution of tin and the effect of tin on concentrations of several essential elements in rabbit.

The organ distribution and the effects of administration of tin, 5 mumol/kg/day, for 6 days on calcium, copper, iron, magnesium, phosphate, and zinc concentrations in plasma, erythrocytes, liver, kidney, and spleen of adult rabbits were studied. Kidney contained the highest concentration of tin, 15.0 +/- 1.64 micrograms/g wet weight (mean +/- S.D., n = 4). The concentrations of copper, phosphate, and magnesium increased significantly in the kidney, while magnesium concentration decreased in erythrocytes 1 day after the administration of tin for 6 consecutive days. A high correlation coefficient between magnesium and phosphate was observed in all organs tested. The correlation coefficients between P vs. Cu, P vs. Ca, and Mg vs. Ca in the liver were lowered during the period of tin administration, whereas those between P vs. Zn, Mg vs. Zn, and Cu vs. Zn in the kidney disappeared after tin administration was completed.

Animals↗
PubMed1984

The in vitro effects of zinc and manganese on delta-aminolevulinic acid dehydratase activity inhibited by lead or tin.

The effects of the administration of lead and tin on delta-aminolevulinic acid dehydratase (5-aminolevulinate hydro-lyase, ALAD, EC 4.2.1.24) activity in human, rabbit, and mouse blood were studied in vivo. In addition the ability of zinc, manganese, and dithiothreitol (DTT) to restore ALAD activity in the blood of lead- or tin-treated subjects was examined in vitro. Manganese, zinc, and DTT restored ALAD activity in vitro. The optimal concentration of zinc required in vitro was 10(-4) M in blood of lead-exposed humans and lead- or tin-administered mice, and 10(-3) M in blood of rabbits treated with either lead or tin. Even at the optimal concentration of zinc, the reactivating effect was incomplete, the highest recovery being about one-third of the control activity. However, the simultaneous addition of zinc and DTT increased ALAD activity to levels comparable with those of controls. Manganese was less effective than zinc in restoring ALAD activity in vitro; the effective dose was 10(-2) M in the blood of lead-exposed subjects, while little effect was noted in tin-treated subjects. Manganese was as effective as DTT in protecting against the inhibition of ALAD activity in vitro by excessive zinc. In contrast, DTT restored ALAD activity completely in the blood of tin-treated rabbits and produced about an 80% recovery of enzyme activity in the blood of tin-treated mice, but only a 35% recovery in the blood of lead-treated rabbits. These results suggest that the mechanisms by which lead and tin inhibit ALAD activity are different.

Animals↗
PubMed1984

The effects of stannous chloride on the humoral immune response of mice.

The effects of stannous chloride (SnCl2) on primary and secondary immune responses to sheep red blood cells (SRBCs) were examined in mice. I.p. administration of 167 mumol/kg/day of SnCl2 for 3 consecutive days suppressed the number of splenic indirect plaque-forming cells (PFCs) in the primary response and the hemagglutination (HA) and hemolytic reaction (HR) titers of non-2-mercaptoethanol(2-ME)-treated sera in both the primary and secondary immune response. However, tin affected neither the indirect PFC response nor the antibody titers of the 2-ME-treated sera after the secondary immunization, which was performed on day 6 following the primary immunization. These results suggest that the subacute administration of tin suppresses part of the immune response in which IgM antibody production plays an important role, and that the production of IgG in the secondary immune response is little affected, while the IgG production in the primary response is suppressed or delayed.

Animals↗
PubMed1984

The in vivo effects of manganese and zinc on delta-aminolevulinic acid dehydratase activity inhibited by lead.

The in vivo effects of zinc (Zn) and manganese (Mn) on the activity of delta-aminolevulinic acid dehydratase (5-aminolevulinate hydrolyase, ALAD, EC 4.2.1.24) in blood with and without inhibition by lead and on the functions of the liver and kidney were studied in rabbits. Administration of Zn or Mn alone caused little change in any of the 29 parameters tested at concentrations of 5, 10, 25 or 50 mumol element/kg body weight. Administration of 5 mumol lead/kg inhibited ALAD activity in blood, but it did not induce any marked effects on the indices of hepatic and renal functions. In simultaneous i.v. injection with lead and manganese, both at a dose of 5 mumol/kg, however, the recovery process of ALAD activity was delayed. Three out of 29 parameters tested, beta-lipoprotein, triglyceride and aldolase, increased significantly one day after simultaneous injection with lead and manganese. Equimolar zinc did not show either an antagonistic or cooperative effect on these three parameters and the ALAD activity in blood.

Animals↗
PubMed1984

Isolation and characterization of a high molecular weight actin-binding protein from Physarum polycephalum plasmodia.

A high molecular weight actin-binding protein was isolated from the Physarum polycephalum plasmodia. The protein ( HMWP ) shares many properties with other high molecular weight actin-binding proteins such as spectrin, actin-binding protein from macrophages, and filamin. It has a potent activity to cross-link F-actin into a gel-like structure. Its cross-linking activity does not depend on calcium concentrations. Hydrodynamic studies have revealed that the protein is in the monomeric state of a polypeptide chain with molecular weight of approximately 230,000 in a high ionic strength solvent, while it self-associates into a dimer under physiological ionic conditions. Electron microscopic examinations of HMWP have shown that the monomer particle observed in a high ionic strength solvent is rod shaped with the two-stranded morphology very similar to that of spectrin. On the other hand, under physiological ionic conditions, the HMWP dimer shows the dumb-bell shape with two globular domains connected with a thin flexible strand.

Actins↗
PubMed1984

Molecular size and shape of beta-connectin, an elastic protein of striated muscle.

Connectin is an elastic protein of vertebrate striated muscle, and consists of doublet components, alpha and beta (also called titins 1 and 2). In the present study, beta-connectin isolated in the native state was investigated in order to characterize its molecular size and shape. The molecular weight was approximately 2.1 X 10(6) (SDS gel electrophoresis) or 2.7 X 10(6) (sedimentation equilibrium). The sedimentation coefficient (SO20, w) was 17S in 0.1 M phosphate buffer, pH 7.0. The intrinsic viscosity measured in an Ostwald-type viscometer was 1.8 dl/g. However, the viscosity was greatly dependent on the velocity gradient, and at a very low velocity gradient of 0.0007 s-1, a solution of connectin (0.3 mg/ml) showed a viscosity value of 17,000 cp. Flow birefringence measurements suggested a length distribution ranging from 300 to 450 nm. Electron microscopic observations revealed that connectin is a long flexible filament and the peaks of frequency of length distribution were at 150, 300, 450, and 600 nm. It was tentatively assumed that the connectin molecule is 300-400 nm long and 34-38 nm wide. It is likely that beta-connectin is derived from alpha-connectin, which has an apparent molecular weight of 2.8 X 10(6).

Animals↗
PubMed1984

Thrombin-inhibitory activity of whale heparin oligosaccharides.

Whale heparin was partially digested with a purified heparinase and the oligosaccharide fractions with 8-20 monosaccharide units were isolated from the digest by gel filtration on Sephadex G-50, followed by affinity chromatography on a column of antithrombin III immobilized on Sepharose 4B. A marked difference in the inhibitory activity for thrombin in the presence of antithrombin III was observed between the high-affinity fractions for antithrombin III of octasaccharide approximately hexadecasaccharide and those of octadecasaccharide approximately eicosasaccharide. The disaccharide compositions of these hexadeca-, octadeca-, and eicosasaccharides were analyzed by high-performance liquid chromatography after digestion with a mixture of purified heparitinases 1 and 2 and heparinase. The analytical data indicated that the proportions of trisulfated disaccharide (IdUA(2S)alpha 1----4GlcNS(6S)) and disulfated disaccharide (UA1----4GlcNS(6S)) increased with the manifestation of high thrombin-inhibitory activity, while that of monosulfated disaccharide (UA1----4GlcNS) decreased. The present observations, together with those so far reported, suggest that the presence of the former structural elements, specifically IdUA(2S)alpha 1----4GlcNS(6S), as well as the antithrombin III-binding pentasaccharide at the proper positions in the molecules of whale heparin oligosaccharides is essential for the manifestation of high inhibitory activity for thrombin in the presence of antithrombin III. The structural bases for the manifestation of the anticoagulant activity of whale and porcine heparins and their oligosaccharides are also discussed.

Animals↗
PubMed1984

Ph1-positive and Ph1-negative abnormal cell lines in a child with lymphoblastic lymphoma.

A 7-year-old Japanese boy with Ph1-positive-lymphoblastic lymphoma is described. The diagnosis was based on biopsied tonsils which were enlarged at the time of admission. On the eighth day after admission an enlarged mediastinal mass was detected on a chest X-ray film. The lymphoblasts which appeared in the peripheral blood and bone marrow proved to be T-cells. Chromosome studies on the bone marrow cells revealed two abnormal cell lines; one had a 7;11 translocation and the other a 7;11 translocation and a 9;22 translocation, forming the Ph1-chromosome. The latter line with the Ph1-chromosome was considered to have been derived from the former line without the Ph1. Our findings show that the Ph1-chromosome may be a secondary change in the course of karyotypic evolution.

Bone Marrow↗
PubMed1984

Early lymphoma coexisting with reactive lymphoid hyperplasia of the stomach.

A 55-year-old woman with a small focus of malignant lymphoma, 6 mm in diameter, arising within an area of reactive lymphoid hyperplasia (RLH) of the stomach is reported. The diagnosis of lymphoma was suspected by the preoperative endoscopic biopsy. This is the case of this association with an unusually small lymphoma in the early stage, in support of the view that there may be an intimate histogenetic relationship between lymphoma and RLH.

Female↗