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Biomedical subjects

A Morimoto

Publications and source records attributed to A Morimoto.

At least 181 records · Page 10Linked to original sources
PubMed1981

Synthesis and structure-activity relationships of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]cephalosporin derivatives. V. Synthesis and antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-cephalosporin derivates and related compounds.

In order to improve the antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]-cephalosporins new derivatives having a methoxyimino moiety in the 7-acyl side chain and related compounds were synthesized. Of these, 7 beta-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyiminoacetamido]-cephalosporins were found to possess excellent activity against a variety of Gram-positive and Gram-negative bacteria including beta-lactamase-producing strains. An extensive study of structure-activity relationships led to the selection of 7 beta-[2-(2-aminothiazol-4-yl)-(Z)-2-methoxyiminoacetamido]-3-[(1-methyl-1H-tetrazol-5-yl) thiomethyl]-ceph-3-em-4-carboxylic acid, SCE-1365, for further biological and clinical evaluation.

Bacteria↗
PubMed1980

Inner ear damage induced by bacterial endotoxin.

Repeated i.d. injection doses of endotoxin lipopolysaccharide of E. coli at certain time intervals were found to give rise to the following changes in the inner ear in mice: In the organ of Corti of the cochlea, there were noted degeneration and disappearance of the inner and outer hair cells of the lower turn, partly with a partial disappearance of nerve fibers in the osseous spiral lamina. Degenerative changes seen in the upper turn were of milder degree. The stria vascularis exhibited enlarged intercellular spaces, the appearance of lysosomes in the constituent cells, and degeneration thereof. Changes observed in the vestibular organ were varying degrees of degeneration of types I and II sensory cells of the crista ampullaris and macula as well as a partial disappearance of these cells. The dark cells were found to have undergone such changes as the formation of vacuoles of varying size and widened interspaces between infoldings, thus providing presumptive evidence of a change in the composition of the endolymph. These observations suggest the possibility that Shwartzman reaction might be another probable cause of inner ear deafness or equilibrium disturbances in actual clinical cases which are at present claimed to be of unknown etiology.

Animals↗
PubMed1980

Synthesis and structure-activity relationships of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]-cephalosporin derivatives. I. Synthesis and antibacterial activity of 7 beta-[2-alkyl- and 2-hydroxy-2-(2-aminothiazol-4-yl)-acetamido]cephalosporins.

2-Alkyl- and 2-hydroxy derivatives of 7 beta-[2-aminothiazol-4-yl)acetamido]cephalosporins were synthesized to improve the antibacterial activity of the parent compounds especially against beta-lactamase-producing organisms. Some of these compounds showed an increase in activity against Serratia marcescens (Xb, XXIIIa) and Enterobacter cloacae (Xb, XIV). The 2,2-dimethyl derivative (XXVIIIb) showed a definite loss of activity.

Bacteria↗
PubMed1980

Synthesis and structure-activity relationships of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]-cephalosporin derivatives. II. Synthesis and antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]-7 alpha-methoxycephalosporins.

7 beta-[2-(2-Aminothiazol-4-yl)acetamido]-7 alpha-methoxycephalosporins were synthesized both by acylation of the 7 beta-amino-7 alpha-methoxycephalosporin compound (VIII) and a new direct acyl-exchange reaction of 7 alpha-methoxy-7 beta-phosphoramido compound (VII). Some of these compounds (IXa, IXb) showed higher antibacterial activity than the 7 alpha-unsubstituted compound against beta-lactamase-producing strains of Serratia marcescens and Proteus vulgaris.

Bacteria↗
PubMed1980

Synthesis and structure-activity relationships of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]-cephalosporin derivatives. III. Synthesis and antibacterial activity of 7 beta-[2-amino-2-(2-aminothiazol-4-yl)acetamido]cephalosporins.

New derivatives of 7 beta-[2-(2-aminothiazol-4-yl)acetamido]cephalosporins having amino group at the 2-position of the 7-acyl moiety were synthesized in the hope that they would show improved antibacterial activity. Some of these compounds (XXa, XXd, XVb) showed improved activity against Enterobacter cloacae. Replacement of the annular amino group by a methyl group caused loss of activity.

Bacteria↗
PubMed1977

Long-term effect of medium-chain triglyceride on hepatic enzymes catalyzing lipogenesis and cholesterogenesis in rats.

This study was conducted to investigate the long-term effect of dietary medium-chain triglyceride (MCT) as compared with that of corn oil feeding on lipid metabolism in rats. Both serum cholesterol and triglyceride levels in MCT-fed rats showed significant decrease during the experimental period of eight weeks, although liver cholesterol and triglyceride contents were not distinguishable between the two groups. Significant elevation of the activity of lipogenic enzymes, such as fatty acid synthetase (FAS) and malic enzyme (ME) of the liver, was observed in MCT-fed rats without any fat accumulation of the liver (fatty liver). The increase of lipogenic enzyme activity was accompanied by a significant reduction of essential fatty acids (EFA) such as 18:2 (omega6) and 20:4 (omega6) in total liver lipid. In contrast, hepatic beta-hydroxy-beta-methylglutaryl CoA(HMG-CoA) reductase activity was significantly decreased in MCT-fed rats, that would play an important role in achieving hypocholesterolemia. From these results obtained in a long-term experiment, it is concluded that exogenous MCT depresses the key enzyme catalyzing cholesterol synthesis with a concomitant elevation of lipogenic enzyme activity in the rat liver.

Animals↗
PubMed1975

The fine structure and the protein composition of gamma phage of Bacillus anthracis.

The fine structure of gamma phage of Bacillus anthracis was studied by electron microscopy with a negative-staining technique. The phage has a hexagonal head and a long tail without a sheath. By electrophoresis on polyacrylamide gels, the proteins of the phage particles are separate into 10 polypeptides with molecular weights ranging from 140 000 to 12 000.

Bacillus anthracis↗
PubMedDate not supplied

Preventive effect of long-term aerobic exercise on thrombus formation in rat cerebral vessels.

The antithrombotic effect of long-term aerobic exercise was studied in rat cerebral blood vessels using an argon (Ar) laser-induced thrombosis technique. Rats were subjected to treadmill exercise at 70% VO2max for 2 and 4 months. The number of laser irradiations required to form an occlusive thrombus in the exercise group was significantly increased compared to that of the control group after 2- and 4-month training periods. Fibrinolytic activity increased just after exercise but there was no significant difference between the exercise and the control group in the resting state after a period of exercising conditioning. The results demonstrated that long-term aerobic exercise decreased the thrombotic tendency in rat cerebral vessels and suggested that such exercise might have a protective effect on these blood vessels.

Aerobiosis↗
PubMedDate not supplied

Application of loop diuretics for treatment of sensorineural hearing impairment. Experimental and clinical study.

In a series of animal experiments on guinea pigs and rats, conducted in an attempt to find a better solution for the treatment of sensorineural hearing impairment and tinnitus-known as diseases almost impossible to heal-it was revealed electrophysiologically, biochemically and electronmicroscopically that loop diuretics, referred to as ototoxic drugs, cause an increased amount of the therapeutic preparation to transfer to the inner ear fluid. It is concluded, on the basis of the encouraging results of these experiments, that combined medication with metabolic activator, steroid hormone and loop diuretics is significantly more effective in improving the symptoms of patients with inner ear deafness and tinnitus.

Animals↗
PubMedDate not supplied

A case of Budd-Chiari syndrome successfully treated by transcatheter recanalization of the right hepatic vein and transjugular intrahepatic portosystemic shunt.

A 40-year-old man with Budd-Chiari syndrome due to chronic obstruction of the major hepatic veins was successfully treated by interventional radiologic procedures. Initially, partial splenic embolization was performed to improve thrombocytopenia and coagulopathy of blood. Second, recanalization was done by thrombolic therapy. Finally, the TIPS procedure was carried out through the recanalized right hepatic vein. This resulted in great improvement of Budd-Chiari syndrome, a marked decrease in pressure, and disappearance of gastroesophageal varices on endoscopy.

Adult↗