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Biomedical subjects

K Azuma

Publications and source records attributed to K Azuma.

At least 127 records · Page 7Linked to original sources
PubMed1985

[Correlation between serum prolactin secretion patterns and the ability of fertilization and cleavage of human oocyte (effects of transient hyperprolactinemia on fertilization and cleavage of human oocyte)].

To assess the effect of serum prolactin (PRL) on the fertilization and cleavage of oocytes, its secretion patterns in normoprolactinemic women (28 cases, 35 cycles) who had undergone IVF-ET because of bilateral tubal occlusion and/or severe oligospermia, and the relationship between its levels and the fertilization and cleavage rate were studied. Three serum PRL secretion patterns were observed. In the TIP-O (Transient Increase in serum PRL in the Ovulatory phase) group (7 cycles), the serum PRL was significantly increased in the ovulatory phase compared with the follicular phase. In the TIP-OL (TIP at the Ovulatory and mid-Luteal phase) group (11 cycle), it was significantly increased in both the ovulatory and the mid-Luteal phases, but in the NON-TIP group (17 cycles) there was no significant increase in any phase. The fertilization rate of the TIP-OL group (60.0%) was lower than that of the NON-TIP Group (89.5%) and the TIP-O group (87.5%). The cleavage rate of the TIP-O group (50.0%) was rather lower, and that of TIP-OL group (30.0%) was significantly (p less than 0.05) lower than that of the NON-TIP group (78.9%). These results suggest that transient increase in serum PRL may suppress the ability of fertilization and cleavage of human oocytes.

Adult↗
PubMed1985

Alkali-catalyzed isomerization of some nitrogen-bridged furanosyl uracils to the corresponding pyranosyl cyclonucleosides.

With a view to examine the possibility of introducing an "up" amino residue into the sugar moiety of uracil nucleosides through 2,3'-N-cyclonucleosides, 2,3'-imino and 2,3'-substituted imino-1-(5'-O-benzoyl-beta-D-lyxofuranosyl)uracils, 2a4, 2b5 and 2c-f, were synthesized and debenzoylated correspondingly to 3a4, 3b5 and 3c-f. Hydrolysis of 3a,c,d,e with one to one mixture of 6N-NaOH and EtOH allowed the isolation of the corresponding 2,3'-N-bridged lyxopyranosyl nucleosides 4 in optically active, crystalline form. This is the first example of furanosyl to pyranosyl conversion in the field of pyrimidine cyclonucleosides.

Chemical Phenomena↗
PubMed1984

Effects of anti-shock agents on the re-opened superior mesenteric artery flow.

We investigated intestinal blood circulation after re-opening of a fixed-time occlusion of the superior mesenteric artery (SMA) in rabbits. The SMA root was occluded for 60 minutes, after which blood pressure and SMA flow were monitored for one hundred minutes under the administration with fluid infusion of three anti-shock agents; dopamine, phenoxybenzamine and dexamethasone. The intestinal wall tissue circulation in parallel with SMA flow was also studied. Blood pressure and SMA flow decreased after release of the SMA occlusion (SMAO), as compared those during pre-occlusive time in the control group. Fluid infusion alone did not improve blood pressure and SMA flow. Pre-administration of dexamethasone with fluid infusion improved blood pressure, SMA flow and the survival rate. Phenoxybenzamine with fluid infusion improved SMA flow, despite the low blood pressure. Circulatory damage to the intestinal wall was more extensive than that to SMA flow. These findings suggest that the severity and mortality of SMAO shock was not caused by plasma loss but rather by toxic metabolites and endotoxin from the ischemic intestine.

Animals↗
PubMed1984

[Hepatic glycolytic intermediates and glucoregulatory enzymes in septic shock due to peritonitis: experimental study in rats].

The hypoglycemia in septic shock due to peritonitis indicates deranged carbohydrate metabolism. To determine if this metabolic failure could be attributed to changes of glucoregulatory enzymes and glycolytic intermediates, activities and changes of these substances in septic shock have been studied in rats. Liver tissue was sampled 5 hours after induction of peritonitis by cecal incision in fasted male rats. Hepatic glycolytic intermediates were assayed by UV-spectrophotometry. Peritonitis caused 33% decrease in glucose-6-phosphate (G6P), a 2.5 fold increase in fructose-1,6-diphosphate (FDP) and a 3.5 fold increase in lactate. Phosphoenolpyruvate (PEP) levels did not show a significant increase in peritonitis. We investigated activities of glucose-6-phosphatase (G6Pase), fructose-1,6-diphosphatase (FDPase), phosphofructokinase ( PFKase ) and pyruvate kinase ( PKase ) in mitochondria-free supernatants from rat liver homogenates. Tissue was sampled 5 hours after induction of peritonitis by cecal incision. Assays were conducted at optimal substrate levels at pH 7.4; NADH charges produced by coupled reactions were determined by UV-spectrophotometry. A significant increase of PFKase and PKase specific activity was observed. These changes were consistent with stimulated glycolysis. For gluconeogenesis to achieve maximum efficiency it would be necessary to inhibit PFKase and PKase completely.

Animals↗
PubMed1983

Endogenous endotoxin absorption and the role of intestinal lymphatics.

We investigated the absorption routes of endotoxin derived from the intestine of rabbits with or without thoracic duct lymph drainage (TDLD). The intestinal circulatory disorders induced were superior mesenteric artery occlusion (SMAO) and superior mesenteric vein occlusion (SMVO). Detection and quantitation of endotoxin in plasma and lymph were carried out using a synthetic chromogenic substrate (peptide-4-methyl-coumarin amide, MCA). In the SMAO group, endotoxin levels in portal plasma exceeded levels in lymph from the thoracic duct throughout the experiment, and in the SMVO group, the relationship was reversed. In peripheral arterial blood, endotoxin levels were significantly lower in rabbits with TDLD than in those with intact lymphatic system. Intestinal lymphatics probably play an important role in appearance of systemic endotoxemia in non-septic shock.

Absorption↗
PubMed1983

[Combination action of sisomicin, dibekacin and cefotetan, cefotaxime, latamoxef, and cefsulodin against Escherichia coli, Serratia marcescens, and Pseudomonas aeruginosa].

The combined actions of sisomicin (SISO), dibekacin (DKB) and cefotetan (CTT), cefotaxime (CTX), latamoxef (LMOX), cefsulodin (CFS) against E coli KC-14, S. marcescens T-55 and P. aeruginosa E-2 were studied. The following results were obtained. The combination of SISO-CTT, SISO-CTX, SISO-LMOX, SISO-CFS, DKB-CTT, DKB-CTX, DKB-LMOX and DKB-CFS using the checker board dilution method on E. coli KC-14, S. marcescens T-55, P. aeruginosa E-2 were found to have a synergistic effect and the minimum FIC index values were 0.26--0.50 for SISO and 0.28--0.75 for DKB, respectively. With the killing kinetic method, all combinations tested showed a synergistic effect.

Anti-Bacterial Agents↗
PubMed1982

The action of phosphodiesterase inhibitors on the hypersensitivity of frog photoreceptor.

The increase in sensitivity of frog photoreceptors after illumination, "hypersensitivity", was studied by recording fast-PIII responses of the isolated bull frog retina superfused with physiological saline containing 5 mM sodium aspartate. The hypersensitivity is mot marked after illumination which bleaches only 0.01% of the rhodopsin initially present. The wavelength of light, which is optimum to induce the hypersensitivity, is about 500 nm. Several kinds of phosphodiesterase inhibitors, isobutylmethylxanthine (IBMX), papaverine, theophylline and caffeine act to induce the hypersensitivity, as does lowered extracellular concentrations of calcium ion, [Ca2+]out. Such action of phosphodiesterase inhibitor can be antagonized by an increase in [Ca2+]out. The relation between effects of Ca2+ and cyclic nucleotides on photoreceptor is discussed.

1-Methyl-3-isobutylxanthine↗