Search PubMed⌕ Search

Biomedical subjects

Y Nishimura

Publications and source records attributed to Y Nishimura.

At least 1,171 records · Page 65Linked to original sources
PubMed1981

[Fundamental and clinical studies on cefotaxime in the field of obstetrics and gynecology (author's transl)].

UNLABELLED: Fundamental and clinical studies were made on cefotaxime (CTX), a new cephalosporin antibiotic. The following results were obtained: 1. Antibacterial activity: At a concentration of 3.13 mcg/ml, CTX inhibited the growth of 90.2% of 92 strains of Gram-negative rods and 80.0% of 15 strains of Gram-positive cocci. 2. Concentrations of CTX in body fluids and genital organs after 2 g i.v.: (1) CTX level in pus reached the peak (5.6mcg/ml) at 2 hours after administration. (2) Mean CTX levels in the pelvic space exudate reached the peak (28.0 mcg/ml) at 2 hours after administration. (3) CTX levels in the uterine appendages and uterus reached the peak (8.9 and 4.5 mcg/g, respectively) at 100 to 280 minutes after administration. 3. CLINICAL RESULTS: CTX was excellent in 7 of 13 cases and good in the remaining 6 cases. The response rate to CTX was 100%. 4. The bacteriological effect: The bacteriological effect of CTX was also 100%. Bacteria were eradicated in 7 of the 10 cases where organisms were demonstrated before CTX treatment. Partial reduction bacteria was observed in the remaining 3 cases. 5. No side effect attributable to CTX was observed.

Adult↗
PubMed1981

Combination therapy using 9,3"-di-O-acetyl-midecamycin with beta-lactam antibiotics against Pseudomonas aeruginosa infection.

The combined effect of beta-lactam antibiotics and 9,3"-di-O-acetylmidecamycin were examined in 10 patients diagnosed as having chronic respiratory tract infections and complicated urinary tract infections. Patients were initially treated with 3 to 10 g/day of beta-lactams as intravenous infusions or by oral route for a certain period, after which period they were treated concurrently with 0.3 to 0.9 g/day of 9,3"-di-O-acetylmidecamycin by oral route. Through this combination therapy eradication of P. aeruginosa was obtained in 2 cases and remarkable decrease in another 2 cases out of the 10 cases. This combination therapy was judged to be effective in these 4 cases. Of the remaining cases, P. aeruginosa was eliminated before the start of the combination therapy in 3 cases, and no change in bacterial count was noted after the combination therapy in the other 3 cases.

Adult↗
PubMed1981

[Study of cefamandole in neonatal purulent meningitis caused by E. coli (author's transl)].

Cefamandole (CMD) was intravenously drip infusion administered at daily dose of 400 mg/kg to the neonate with purulent meningitis caused by E. coli which was resistant to ABPC. In clinical application, CMD was evaluated as effective, although 6 mg/kg/day of GM given concomitantly. No adverse effect and abnormal laboratory findings were observed. This study would support the clinical usefulness of CMD in severe neonatal infection especially like meningitis.

Cefamandole↗
PubMed1980

Hereditary deficiency of lactate dehydrogenase M-subunit.

A family with a complete deficiency of lactate dehydrogenase M-subunit was investigated. The propositus was an 18-year-old male who complained of exertional pigmenturia and easy fatigue. Marked discrepancy was observed in the ratio between creatine kinase and lactate dehydrogenase (CK/LDH). Electrophoretic analysis of serum LDH isoenzymes of the propositus demonstrated only one activity band of LDH H4. A complete lack of the LDH M-subunit was similarly demonstrated in erythrocytes, leukocytes and in the intermediate vastus muscle. LDH levels in the muscle specimen were markedly decreased in the patient, whereas CK and aspartate aminotransferase were almost the same as in a control subject. LDH isoenzymes of erythrocytes were analyzed in 5 siblings and in the parents. This demonstrated a complete lack of LDH M-subunit in 3 siblings. The ratio between H-subunit and M-subunit (H/M) in erythrocyte LDH suggested a partial absence of the M-subunit in two siblings and in the parents. An abortive increase of blood lactate and a marked increase in blood pyruvate were observed immediately after ischemic work of the forearm, accompanied by an increase in serum creatine kinase and myoglobinuria. The present case represents a newly described form of genetically determined myopathy.

Adolescent↗
PubMed1980

An HLA-linked immune suppression gene in man.

Genetic control of immune response in man was investigated with the system of antigen-specific T cell proliferation in vitro against streptococcal cell wall (SCW) antigen. Family analysis by Morton's maximum likelihood scoring method revealed that the low response to SCW antigen was controlled by a single dominant gene. Furthermore, this gene was shown to be closely linked to HLA (lod score was 3,209 at theta = 0). This is the first description of the HLA-linked immune suppression gene in man. The possible mechanism for this gene action was discussed.

Adult↗
PubMed1980

On the base-stacking in the 5'-terminal cap structure of mRNA: a fluorescence study.

The fluorescence at 370 nm of the 7-methylguanosine residue (m7G) is found to be quenched when the base residue is involved in a stacking interaction with the adenosine residue in the cap structure m7G5' pppA of an eukaryotic mRNA. On the basis of the observed degree of quenching, the amounts of the stacked and unstacked forms in the cap structure have been determined at various temperatures and pH's. It has been found that at pH 6.2 effective enthalpy and entropy in the unstacked leads to stacked change are delta H degrees = 4.4 +/- 0.1 kcal/mole and delta S degrees = - 14.3 +/- 0.2 e.u., respectively. The pka value for the m7G residue is found to be 7.7 at 10 degrees C and 7.3 at 30 degrees C. The stacked structure seems to be less favourable in the deprotonated form that occurs in the higher pH solution. A similar analysis of some other cap structures indicates that the stacked form in m7G5' pppN structure is favourable if N is a purine nucleoside or a 2'-O-methylpyrimidine nucleoside but not for an unmethylated pyrimidine nucleoside.

Adenosine↗
PubMed1980

Clasping structure in the double cone of the retina of the turtle (Gyoclemys reevesii).

The double cone of the turtle retina was reconstructed three-dimensionally from electron micrographs of 400 serial sections. Cytoplasm of the accessory cone extends bilaterally to surround the principal cone incompletely. The cytoplasmic extensions are 0.1 microns in width and 2 microns in length at their longest portions. They arise at approximately the median portion of the ellipsoid (consisting of mitochondria) and terminate at the level of the outer limiting membrane. The possible function of these extensions as a clasping structure is discussed.

Animals↗
PubMed1980

Determination of the developmental pattern of retinal ganglion cells in chick embryos by Golgi impregnation and other methods.

The differentiation of retinal ganglion cells was investigated in chick embryos, with special attention to accurate incubation times from stage 20 (about 3 days of incubation) to after hatching (after 20 days of incubation). The morphological differentiation of these cells comprised four main events: 1. Shortening of the bipolar processes attached to the inner and outer limiting membranes and the sprouting of an axon from part of the cell body. These were recognized at stage 25 (about 4.5 days of incubation) by Golgi impregnation methods. 2. Beginning of differentiation of the dendrites, which was recognized at stage 29 to 31 (about 6 or 7 days of incubation). 3. The rapid development of the dendrites. This occurred at stage 34 (about 8 days of incubation). 4. The essential completion of the retinal ganglion cells, which was recognized at stage 39 (about 13 days of incubation).

Animals↗
PubMed1980

On the process of cellular division in Escherichia coli: isolation and characterization of penicillin-binding proteins 1a, 1b, and 3.

Multiple mutants of Escherichia coli defective in penicillin-binding proteins (PBPs) were constructed, and into these strains Co1E1 plasmids carrying the genes for PBP-1a, -1b, or -3 were introduced. From these plasmid-carrying strains, PBP-1a and -1b were purified by ampicillin-Sepharose affinity chromatography and PBP-3 by cephalexin-Sepharose affinity chromatography. Improved purification was achieved by differential elution with NH2OH. Purified PBP-1b synthesized murein when added to the membrane fraction of a PBP-1b-defective mutant, which by itself failed to support murein synthesis in vitro. The PBP-1b preparation was able to synthesize murein from the lipid intermediate extracted with chloroform/methanol but was unable to utilize UDP-linked precursors for murein synthesis. Murein synthesis was inhibited by vancomysin, ristocetin, moenomycin, and enduracidin, but not by beta-lactam antibiotics. The synthesized murein was shown to contain crosslinked muropeptides. Their crosslinking was abolished by action of beta-lactam antibiotics. The PBP-1a and -3 preparations showed substantially no activity for murein synthesis in the same reaction system. None of the three PBPs showed D-alanine carboxypeptidase activity with UDP-N-acetylmuramoyl-pentapeptide as substrate or endopeptidase activity with bis(disaccharide-peptide) as substrate.

Bacterial Proteins↗
PubMed1980

A mutant of Escherichia coli defective in penicillin-binding protein 5 and lacking D-alanine carboxypeptidase IA.

A mutant of Escherichia coli defective in penicillin-binding protein 5 activity was isolated. The mutation (pfv) was shown to be located at 14.0 min on the E. coli chromosome map. Loss of penicillin-binding protein 5 in the pfv mutant was associated with the loss of D-alanine carboxypeptidase IA activity and increased sensitivity to beta-lactam antibiotics. We conclude that penicillin-binding protein 5 catalyzes the major D-alanine carboxypeptidase IA activity and that the enzyme activity, in vivo, protects E. coli cells from killing by low inhibitory concentrations of beta-lactam antibiotics.

Bacterial Proteins↗
PubMed1980

Sequential computed tomography scans in acute cerebral infarction.

Sequential computed tomography (CT) scans were obtained in 30 patients with acute cerebral infarction. In some cases, infarction was seen on the scans as early as three to six hours after onset of symptoms. Although small areas of petechial hemorrhagic infarction are not easily detected by currently available equipment, positive contrast enhancement helps locate petechial hemorrhagic infarction, which is usually in the cortical gray matter of the cerebral mantle and the central gray matter of the deep central gray matter. Contrast-enhanced CT scans are a useful method for detecting small infarctions. However, when a CT scan is performed within five days of ictus, contrast enhancement is usually not required.

Acute Disease↗
PubMed1980

Ca2+ removal effects on bullfrog gastric mucosa in the presence of drugs.

Bullfrog gastric mucosa can secrete acid in vitro for more than 24 hr. In Ca2+-deficient media, the acid secretion measured by pH stat method gradually decreased to cease about 200 min after the start of immersion in the media. When A23187 or quinidine, which are known to mobilize Ca2+ from the intracellular pools, was present on the submucosal side, a prolongation of the duration of acid secretion in the absence of Ca2+ was found. Dibutyl c-AMP also induced a similar prolongation. Histamine or theophylline not only prolonged the duration of acid secretion but also transiently increased the acid secretory rate over the control level. Based upon the known fact that there are different intracellular Ca2+ compartments, i.e, one related to the process of acid secretion and the other to the maintenance of junctional complexes, the present results of drug effects were discussed especially in regard to their Ca2+ mobilizing effects. Cessation of acid secretion in a K+- and Ca2+-deficient solution occurred much more quickly than that in a Ca2+-deficient or a K+-deficient medium.

Animals↗