Biomedical subjects
Publications and source records attributed to H Okada.
Acrinol, which is used as a disinfectant and an abortifacient in several countries, was tested for mutagenicity by the Ames test system. After incubation with a rat-liver S9 microsomal preparation, acrinol showed potent mutagenicity for Salmonella typhimurium strains TA98 and TA100, although it had no direct mutagenicity for the microorganisms.
To clarify the relation between steroids and prolactin (PRL) production in human decidua, the levels of estrogen receptors (ERs), progesterone receptors (PRs), and androgen receptors (ARs) and the level of PRL in the decidua were determined simultaneously during early pregnancy. Cytosol, nuclear, and total ER levels and the cytosol PRL level were found to increase with the advance of gestation; whereas levels of PRs and ARs remained constant. Multiple regression analysis showed that the multiple correlation coefficient in the relationships of cellular ERs and cytosol PRL with gestational age was 0.722 and relatively high among the others. These results suggest an association between estrogen and decidual growth. Significant correlations between the cytosol PRL level and cellular PR or AR levels were seen during early pregnancy, suggesting that progestin and androgen may regulate PRL synthesis.
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Squalene analogs such as lycopersene, geranylfarnesyl, digeranyl, and 2-hydroxy-2,3-dihydrosqualene and terpene alcohol derivatives such as farnesyl benzyl ether, farnesyl pivalate, geranylgeranyl pivalate, geranyl pivalate, and geranyl benzyl ether were oxidized by Corynebacterium sp. strain SY-79, which was isolated from soil by using squalene as a carbon source. Lycopersene and geranylfarnesyl gave no major product. Digeranyl, geranyl benzyl ether, and geranyl pivalate gave terminal oxidation products, and 2-hydroxy-2,3-dihydrosqualene, farnesyl benzyl ether, farnesyl pivalate, and geranylgeranyl pivalate were degraded to give lower molecular carboxylic acids. Strain SY-79 showed promising oxidative activities toward acyclic terpenes, although the metabolites obtained were variable, depending upon the structure of the substrate.
By cloning the beta-galactosidase gene of Bacillus stearothermophilus IAM11001 (ATCC 8005) into Bacillus subtilis, enzyme production was enhanced 50 times. beta-Galactosidase could be purified to 80% homogeneity by incubating the cell extract of B. subtilis at 70 degrees C for 15 min, followed by centrifugation to remove the denatured proteins. Because of its heat stability and ease of production, beta-galactosidase is suitable for application in industrial processes.
The systemic injection of an aqueous suspension of cell wall or its peptidoglycan (PG)-rich sonicate derived from group A streptococcus and Lactobacillus casei induced acute joint lesions in BALB/c, DBA/1J, (BALB/c X DBA/1J)F1, and C3H/He mouse strains, but not in C57BL/6, DBA/2, and AKR strains. Cell walls and their enzymatically degraded PG fragments from other bacteria as well as the synthetic disaccharide dipeptide and Lactobacillus plantarum cell wall-derived disaccharide tripeptide produced similar acute inflammation in susceptible BALB/c mice. Acute swelling and erythema of the ankles and wrists were observed as early as 3 h, reached maximum severity by day 2, and generally subsided by days 4 to 6 after injection. Histological studies showed synovial proliferation, marked infiltration of many mononuclear cells and a few polymorphonuclear leukocytes in the soft tissues, and extensive deposition of fibrinous exudate in the joint space. Antibody response was detectable against the PG fraction. However, anti-PG antibody does not seem to be responsible for the pathogenesis of this disease. On the other hand, experiments on decomplementation by cobra venom factor suggest that complement components are involved in the early phase of this arthritic model.
The effect of estrogen on the induction of human endometrial peroxidase was studied in vitro. When 17 beta-estradiol was added to the incubation medium, endometrial peroxidase activity was markedly increased, and the highest enzymatic activities were reached at about 12 h of incubation. The ability of estrogen and related compounds to increase peroxidase activity at a concentration of 10(-7) M was 17 beta-estradiol greater than estrone greater than 17 alpha-ethynylestradiol greater than estriol = diethylstilbestrol. Mestranol, progesterone, and testosterone had almost no activity. The induction of peroxidase by 17 beta-estradiol was inhibited by actinomycin D or cycloheximide. This method may be useful for determining the direct estrogenic effect of compounds in human endometrium.
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To support the estrogen hypothesis in the pathogenesis of leiomyoma, total cellular estrogen receptor (ER) levels (the sum of levels in cytosol and nuclear KCl-extractable and nuclear non-KCl-extractable fractions) were assayed and compared with levels of progestin (PR) and androgen (AR) receptors in the leiomyoma and the corresponding myometrium. The ratios of ER to PR or AR levels were higher (with statistical significance) in leiomyoma than in the corresponding normal myometrium, both in terms of total cellular levels in each individual case and nuclear levels. It appears that estrogen sensitivity is higher in the leiomyoma than in the corresponding myometrium, due to the relative increase in ER.
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In 1981, P. Talbot developed a triple-stain technique to estimate the number of human sperm undergoing normal acrosome reaction in fixed smears. In this method, live and dead sperm are first differentiated using the vital stain trypan blue. Sperm are then fixed in glutaraldehyde, dried onto slides, and the postacrosomal region and acrosome are differentiated using Bismark brown and Rose Bengal. Slides are examined at 1,000x with a bright-field microscope and assessed for the percentage of sperm that have undergone the normal acrosome reaction. Using this method we examined the time course of the acrosome reaction of human sperm incubated in mBWW the influence of human serum albumin, the calcium concentration of incubation media, Ca ionophore A 23187, and trypsin on the acrosome reaction of human sperm and the difference between the percentage of sperm undergoing normal acrosome reaction of fertile and infertile males. We got the following results: The percentage of human sperm undergoing acrosome reaction increased for the first six hours of incubation. Without human serum albumin the acrosome reaction did not occur. Ca ion could be one of the triggers of the acrosome reaction. Ca ionophore A23187 and trypsin induced the acrosome reaction in vitro. Sperm from oligozoospermic males, especially poorly motile sperm, could not undergo acrosome reaction so easily as sperm from fertile males could.
Although sialoglycolipids on liposome membranes were able to inhibit the activation of the alternative complement pathway (ACP) of guinea pigs mediated by trinitrophenylaminocaproyldipalmitoylphosphatidylethanolamine, they scarcely inhibited the ACP activation mediated by natural antibody to paragloboside (PG) inserted into the liposome membranes. Therefore, ACP activation was able to proceed regardless of the presence of sialoglycolipids on heterologous cell membranes when antibodies to constituents of the membranes were available. On the other hand, sialoglycolipids effectively inhibit undesirable ACP activation on self cell membranes, because little if any antibody is reacting on the self cell surface. Thus, the natural antibody reaction may effectively discriminate between self and non-self cell surface by cooperation with complement inhibitors on cell membranes such as sialoglycolipids.
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