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Biomedical subjects

K Inomata

Publications and source records attributed to K Inomata.

At least 37 records · Page 2Linked to original sources
PubMed1997

Condensation of glycylglycine to oligoglycines with trimetaphosphate in aqueous solution. II: catalytic effect of magnesium ion.

The previously reported condensation reaction of glycylglycine with trimetaphosphate (Yamanaka et al., 1988) was reinvestigated and shown to be catalyzed by magnesium ion. Aqueous solutions containing glycylglycine (0.5 M), trimetaphosphate (0.5 M) and magnesium chloride (0.5 M) were incubated at 38 degrees C at pH 4, 5, 6, 7 and 8. After incubation for ten days at pH 5, the maximum yields of tetraglycine and hexaglycine as condensation products were found to be about 12 and 1.4%, respectively. This result indicated the presence of a considerable catalytic effect of magnesium ion compared with the maximum yield of about 2% for tetraglycine and approximately 0% for hexaglycine in the absence of magnesium ion.

Evolution, Chemical↗
PubMed1996

Trans-kingdom conjugation between Agrobacterium tumefaciens and Saccharomyces cerevisiae, a bacterium and a yeast.

For conjugation between prokaryotic Agrobacterium tumefaciens and eukaryotic Saccharomyces cerevisiae, we constructed two novel conjugative plasmids. A. tumefaciens transmitted the plasmids to S. cerevisiae with the aid of tra genes on a helper plasmid. The transmitted plasmids retained their original structure and function in transconjugant yeasts. The presence of Ti plasmid barely affected the trans-kingdom conjugation.

Agrobacterium tumefaciens↗
PubMed1995

Specific effect of magnesium ion on 2',3'-cyclic AMP synthesis from adenosine and trimeta phosphate in aqueous solution.

Phosphorylation of adenosine by trimetaphosphate was investigated using various catalysts in aqueous solution under mild conditions at pH approximately 7.0 and at 41 degrees C. The product was primarily 2',3'-cyclic AMP together with smaller amounts of ATP. Magnesium ion was found to have a remarkable catalytic effect of approximately one hundred times greater than the other chemicals tested. The mechanism for the specific effect of magnesium ion is discussed.

Adenosine↗
PubMed1995

Effect of Porphyromonas gingivalis ATCC 33277 vesicle on adherence of Streptococcus mutans OMZ 70 to the experimental pellicle.

The vesicles of Porphyromonas gingivalis ATCC 33277 strongly aggregated Streptococcus cricetus, S. rattus, and S. mutans, but poorly aggregated S. sobrinus. The adherence of S. mutans OMZ 70 to hydroxyapatite (HA) coated with whole saliva was increased in parallel with the quantity of the vesicles. The significant increase of adherence of S. mutans OMZ 70 by the vesicles was also observed on the HA coated with parotid saliva, submandibular saliva, serum, and type I collagen. These findings suggest that the vesicles may act as a bridge between mutans streptococcus and the tooth surface.

Animals↗
PubMed1995

Effects of angle of model-demonstration on learning of motor skill.

The purpose was to examine the effects of three different demonstrations by a model on acquisition and retention of a sequential gross movement task. The second purpose was to examine the relationship between reversal processing of visual information about skills and coding of skill information. Thirty undergraduates (15 men and 15 women) were assigned into one of three conditions, Objective condition which demonstrated the task with the model facing the subject. Looking-glass condition in which the skill was demonstrated with the model facing the subject who viewed the performance opposite the right and left directions in executing the task, and the Subjective condition in which the subject observed the model from the rear. Number of immediate recall tests required to accomplish the sequential movements completely and the sum of the performance points for reproduced movements at each delayed recall test (1 day, 7 days, and 5 mo. after the immediate recall test) were employed. Analysis indicated the Subjective condition produced a significantly greater modeling effect in immediate recall of the movements than the Looking-glass condition. Retention of the acquired skills was almost equal under the three conditions.

Adult↗
PubMed1994

Coaggregation between Porphyromonas gingivalis and mutans streptococci.

Coaggregation occurred between Porphyromonas gingivalis and mutans streptococci. The coaggregation was completely inhibited by L-arginine, N alpha-p-tosyl-L-lysine chloromethyl ketone (TLCK), and a trypsin inhibitor, and weakly inhibited by L-lysine, N-ethylmaleimide, lysozyme, and human whole saliva. The results of heat and proteinase K treatment suggested that a heat-labile proteinaceous substance of P. gingivalis and a heat-stable substance of mutans streptococci may play a role in the coaggregation. Mutans streptococci also aggregated in the presence of the heat-labile factor in the supernatant of P. gingivalis. The aggregation was also inhibited by L-arginine, TLCK, and a trypsin inhibitor.

Bacterial Adhesion↗
PubMed1994

The yeast Saccharomyces kluyveri as a recipient eukaryote in transkingdom conjugation: behavior of transmitted plasmids in transconjugants.

The prokaryote Escherichia coli successfully conjugated with the eukaryote Saccharomyces kluyveri, which is relatively distant from the species S. cerevisiae. To achieve this transkingdom conjugation, we constructed three types of conjugative plasmids, namely integrative, replicative, and centromere vectors, for S. cerevisiae. By transfer of any of the three plasmids from E. coli, an S. kluyveri Ura- mutant was converted to the Ura+ phenotype. This phenotype was easily lost under nonselective conditions. Southern analysis of the transconjugants clearly indicated the presence of the plasmids in many different structures and sizes.

Conjugation, Genetic↗
PubMed1993

Spontaneous cortical granule release and alteration of zona pellucida properties during and after meiotic maturation of mouse oocytes.

Exocytosis of cortical granules (CGs) and the concomitant electron density changes of the zona pellucida (ZP) in the absence of sperm penetration were investigated in mouse oocytes processed with tannic acid containing fixation at various stages during and after maturation. After fusion of the CG membrane with the plasma membrane, the CG contents became very electron-dense, due to tannic acid. CG material is seen to be made up of coarse granular structures which gradually change to fine amorphous structures, which accumulate within the developing perivitelline space (PVS). When the coarse CG material attaches to the ZP, small domains exhibiting higher electron density appeared, and the number of these domains gradually increased. Release of CG was observed from metaphase I through metaphase II. In metaphase I to immediately after ovulation, the higher electron density of ZP and CG release was restricted to the cortical area overlying the meiotic spindle. Finally, the CG-free domain formed itself overlying the meiotic spindle as a result of CG release. However, in oviductal ova, CG release additionally occurred in the hemisphere opposite the spindle. At this stage the entire PVS was well developed and contained numerous fine electron-dense materials. Moreover, the inner half of the ZP increased in electron density as well. This change in electron density of the ZP might be associated with released CG material. These results suggest that the "partial cortical reaction" may play an important role in conditioning the ZP prior to ZP reaction.

Animals↗
PubMed1993

Biological monitoring of acrylonitrile exposure through a new analytical approach to hemoglobin and plasma protein adducts and urinary metabolites in rats and humans.

A new, simple and fast procedure of measuring acrylonitrile (ACN) in ACN derived mercapturic acids such as S-(2-cyanoethyl)-L-cysteine(CyEC), and in hemoglobin (Hb) and plasma protein adducts and urinary metabolites in rats and humans exposed to ACN was developed. ACN in mercapturic acids or proteins was analyzed by capillary gas chromatography (GC) by liberating ACN at a high-temperature in the injector port of GC with or without oxidizing sulfur atoms of the ACN-bound cysteines into sulfoxide form by hydrogen peroxide in vitro. At 350 degrees C, more than 90% of ACN in authentic CyEC was recovered by this method. Increasing a single ip dose of ACN from 5 to 50 mg/kg produced proportional increases in ACN bound to Hb 24 hr after the treatment. The alkylation of plasma protein with ACN was about 1/10 as low as that of Hb. After repeated daily ip doses of 1-10 mg/kg, ACN in Hb decreased with a half-life of about 9 days. ACN was also detected in the blood of workers exposed to ACN for 1 to 10 years at a Siberian synthetic rubber factory.

Acetylcysteine↗
PubMed1993

The confronting cisternae in the hippocampal neurons of rats and Japanese monkeys.

The ultrastructure of the neurons in the hippocampal formation of Wistar rats and Japanese monkeys was investigated. Confronting cisternae were observed in the cytoplasm of pyramidal neurons and granule cells. The structures were composed of closely apposed parallel cisternae, presumably continuous with the cisternae of the rough endoplasmic reticulum. The cytoplasmic matrix between the confronting cisternae contained electron dense flocculent material. In the pyramidal neurons irregular confronting cisternae were also observed. Possible functions of the confronting cisternae are discussed.

Animals↗