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Biomedical subjects

I Suzuki

Publications and source records attributed to I Suzuki.

At least 397 records · Page 22Linked to original sources
PubMed1977

Immunohistochemical detection of Fc receptor. I. Light microscopic demonstration of Fc receptor by using soluble immune complexes of peroxidase-antiperoxidase immunoglobulin G.

The mouse mesenteric lymph node cells (in the cell suspension and frozen sections) were incubated in the soluble immune complexes of peroxidase-antiperoxidase immunoglobulin G. After being washed, they were reacted with diaminobenzidine tetrahydrochloride. Light microscopically brown-colored granules were observed on the cell surface of a proportion of small lymphocytes. In frozen sections, a proportion of small lymphocytes were stained dark brown on the cell surface. Characterization and control experiments suggest that the binding of peroxidase-antiperoxidase immunoglobulin G to the cell surface is mediated by Fc receptor. Peroxidase-antiperoxidase immunoglobulin G, therefore, can be used as in indicator of Fc receptor.

Animals↗
PubMed1977

Immunohistochemical detection of Fc receptor. II. Electron microscopic demonstration of Fc receptor by using soluble immune complexes of ferritin-antiferritin immunoglobulin G.

The mouse mesenteric lymph node cells were incubated in the soluble immune complexes of ferritin-antiferritin immunoglobulin G at 37 degrees C for 20 min. After being washed, postfixed with OsO4 and dehydrated by degraded ethanol series, the lymph node cells were observed by electron microscope. Apprroximately 15% of the cells (mainly composed of small lymphocytes) bound ferritin particles to the cell surface. The distribution pattern of the binding of ferritin particles (ferritin-antiferritin immunoglobulin G) took the form of discrete patches of irregular distribution interspaced with unlabeled portions. The electron microscopic features of ferritin particles (ferritin-antiferritin immunoglobulin G) attached to the cell surface suggest that a structure of constant conformation (Fc receptor) situated in the cell membrane takes part in the binding of ferritin-antiferritin immunoglobulin G.

Animals↗
PubMed1977

Antitumor effect of 1,1'-polymethylene-bis (1-nitrosourea) and related compounds.

Polymethylene-bis(1-nitrosourea), polymethylene-bis(1-nitroso-3-nitroguanidine), and polymethylene-bis(1-nitroso-p-toluenesulfonamide) derivatives were tested for antitumor effect against rat ascites hepatoma AH-13 and mouse leukemia L-1210. Bisnitrosoureas were effective against AH-13 and L-1210, bisnitrosoguanidines were effective against AH-13 alone, and bisnitrosotoluene-sulfonamides were ineffective against both tumor lines. Of all these compounds, 1,1'-ethylene-bis(1-nitrosourea) (EBNU) was the most effective. The antitumor effect of EBNU was compared with that of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). Intraperitoneal administration of EBNU according to the schedule, day 1, days 1 and 5, and days 1, 5, and 9 after intraperitoneal inoculation of L-1210 showed marked prolongation of host survival, although the effective doses used were a few times higher than those used in BCNU to obtain a similar effect. The minimum effective dose (MED) of EBNU on AH-13 cells was estimated as 1 mg/kg, which was 10 times less than that of BCNU, suggesting that EBNU was more effective than BCNU against AH-13.

Animals↗
PubMed1977

Difference of anti-complementary effect of double stranded DNA and single stranded DNA.

Anti-complementary effect of both native double stranded DNA and denatured single stranded DNA was examined by the use of phage DNA of microgram level. The distinct difference of anti-complementary effect was detected between the double and single stranded DNA, that is, only single stranded DNA showed the anti-complementary effect. It is supposed that that the anti-complementary effect of single stranded DNA revealed by the present study is different from the anti-Clq effect which reported on both double and single stranded DNA by Agnello et al.

Complement C1↗
PubMed1976

An immunoelectron microscopic analysis of Epstein-Barr virus-associated complement-fixing antigen.

Epstein-Barr virus-associated, complement-fixing antigens have been observed with a complement-mediating immunoreaction and with the peroxidase-labeled anticomplement antibody electron microscopic method. Postive reaction products could be found in the nuclei of P3HR-1 cell lines. At high magnification, it was ascertained that the reaction-positive precipitates were associated with chromatin and were mostly either finely granular or filamentous, which suggests that the antigen was not uniform. It was speculated that the antigen would be analogous to the SV40 T-antigen, since the localization pattern of the positive reaction was similar in both antigens. This new, modified method using complement may also be used for detection of a natural antibody of unknown class or for low-sensitivity systems of antigen-antibody reactions. Thus, this method appears useful for studying various kinds of experimental materials.

Antigens, Viral↗
PubMed1976

The citric acid fermentation by Aspergillus niger: regulation by zinc of growth and acidogenesis.

The citric acid fermentation by Aspergillus niger is divided into two consecutive phases, a growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they produce citrate but do not proliferate, or else do so at a much reduced rate. When studied in a low sucrose (0.4-0.8%) mpinimal salts medium the growth-accumulation alternative was controlled by the concentration of zinc: high zinc (about 1-2 muM) maintained growth phase, while at low zinc (below 1 muM) growth became limited by zinc deficiency and the cultures passed into accumulating phase. Addition of zinc to accumulating cultures resulted in their reversion to growth phase. Iron, manganese, calcium at concentrations as high as 5-10 muM had no influence on either growth or citrate accumulation. These results suggest that zinc plays a role in the regulation of growth and citric acid accumulation.

Aspergillus↗
PubMed1976

Regulation by zinc and adenosine 3',5'-cyclic monophosphate of growth and citric acid accumulation in Aspergillus niger.

The citric acid fermentation by Aspergillus niger is divided into two consecutive phases, growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they excrete citrate but do not proliferate. The phase alternative was controlled by the concentration of zinc: high zinc (2 muM) maintained growth phase, and a zinc 'deficiency' apparently signaled the ransition to the accumulating phase. Cyclic AMP affected the rates of growth and acidogenesis when added to cultures growing at low but not at high zinc: that is, cAMP did not induce the phase transition, zinc deficiency did, Cyclic AMP enhanced growth early in the fermentation, but at later stages the response of the mycelia to cAMP changed, and then cAMP inhibited growth. When citrate eventually began to accumulate cAMP augmented its sypthesis. The growth and acidogenic responses were quite specific to cAMP, and were sensitive to concentrations of about 1 muM. Cyclic AMP also either promoted or retarded the appearance of an unidentified yellow pigment. It is proposed that the growth and accumulating phases are distinct differentiated states, at least with respect to cAMP metabolism.

Adenine Nucleotides↗