Different effects of D-glucose anomers for respiration of bacterial germinated spores.

Effects of alpha- or beta-D-glucose on the respiration of germinated spores (only germinated spores not including swollen spores and elongated spores) of Bacillus subtilis and B. megaterium were studied. In our conditions, net amount of oxygen consumed by 10(10) germinated spores of B. subtilis per min after addition of alpha- or beta-D-glucose was 1.6 microgram or 6.6 microgram (beta/alpha = 4.13), while that by B.megaterium was 4.5 microgram of 6.8 microgram (beta/alpha = 1.51), respectively. However, the net amounts of oxygen consumed by 10(10) vegetative cells per min after addition of alpha- or beta-D-glucose were identical, for B.subtillis in both cases 443.0 microgram and for B.megaterium in both cases 604.4 microgram.     

Isolation and structure of the strong cell growth and tubulin inhibitor combretastatin A-4

The African tree Combretum caffrum (Combretacae) has been found to contain a powerful inhibitor of tubulin polymerization (IC50 2-3 microM), the growth of murine lymphocytic leukemia (L 1210 and P 388 with ED50 approximately 0.003 microM and human colon cancer cell lines [(e.g. LoVo (ED50 = 0.005 microgram/ml), HT 29 (ED50 0.02 microgram/ml, Colo 205 (ED50 = 0.07 microgram/ml), DLD-1 (ED50 = 0.005 microgram/ml) and HCT-15 (ED50 = 0.0009 microgram/ml] designated combretastatin A-4 (1c). The structure assigned by spectral techniques was confirmed by synthesis.     

Reduction of isoprenaline induced tachycardia in pregnant rats. Role of a serum factor]

The in vivo isoprenaline (50 microgram/kg) induced tachycardia (beta 1 adrenergic stimulant effect) was decreased in pregnant (20th day) Rats compared to non pregnant Rats. The in vitro positive chronotropic effect of isoprenaline (10 ng/ml) on cultured Rat heart cells was abolished by pregnant Rat serum whereas progesterone (0.10 to 5 microgram/ml) or oestradiol (0.1 to 25 microgram/ml) were ineffective. The decreased beta 1 adrenergic responsiveness in pregnant Rats could be related to a seric factor, different from these two hormones.     

Cholinesterase activity and expression of axial teratogenesis in quail embryo exposed to organophosphates]

The expression of the axial terotogenesis and the cholinesterasic activities have been studied simultaneously in the Quail embryo. High concentration of malathion (1 000 microgram) slightly reduces the cholinesterasic activities and does not produce morphogenetic disturbance. Bidrin (250 microgram) and parathion (100 microgram), strongly inhibit the cholinesterasic activities producing drastic axial deformities. The use of graduated concentrations of parathion shows that these axial abnormalities take place with a high level of cholinesterase inhibition. With organophosphorus, there is a good correlation between the axial teratogenesis and the cholinesterase inactivation.     

Effects of cortisone and thyroxine on intestinal trehalase activity in infant mouse.

Cortisone acetate (25 microgram/g b.wt/day) administration to 8-day-old suckling mice induces a premature increase of trehalase activity along the entire small intestine. On the other hand, thyroxine (1 microgram/g b.wt/day) in unable to provoke a precocious increase of trehalase activity. Trehalase appears to be the only brush border membrane disaccharidase controlled solely by glucocorticoid hormones during the postnatal maturation of the intestine.     

Comparison of estradiol benzoate and dihydrotestosterone propionate with testosterone propionate on the induction of male-like sexual behavior in female sheep ovariectomized as adults]

Daily I/M injections of 200 microgram of oestradiol benzoate induce in female Sheep, ovariectomized as adults, male-like sexual reactions similar to what is obtained with 10 mg testosterone propionate per day. Simultaneously, a permanent female sexual receptivity is observed. Oestradiol benzoate at the dose of 20 microgram/day, and dihydrotestosterone propionate (10 mg/day) are both totally ineffective. The result support the hypothesis of the necessity of the aromatization of testosterone for the action on sexual behaviour.     

In vitro malignant transformation of hamster lung cells by 2-chlorobutadiene]

Normal Hamster lung cells from an established line were treated with 1-500 microgram . ml-1 2-chlorobutadiene. Those treated with 1 microgram . ml-1 of the compound showed malignant transformations 14 weeks after treatment. The treatment with higher concentrations did not accelerate the transformation process.     

Promotion of epithelial keratinization by N-methyl-N'-nitro-N-nitrosoguanidine in rat forestomach in organ culture.

The effect of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) on epithelial differentiation of fetal rat forestomach was investigated in organ culture. When forestomach tissues removed from 16.5-day fetuses were treated with 5 microgram and 3 microgram of MNNG per ml for 1 h, epithelial keratinization was observed after 4 and 5 days, respectively, whereas it occurred after 6 days in control cultures. A clear dose-response relationship was found in the promotion of epithelial keratinization by MNNG.     

Thiamin turnover rate in some areas of rat brain and liver: a preliminary note.

Thiamin turnover rates in some nervous structures and liver of rats were evaluated in a steady state condition, using thiamin- 14C as a tracer. The radioactivity contents were analyzed by means of a mamillary type compartmental model. Excluding the liver, turnover rate values of the nervous structures were ordered in the following sequence: sciatic nerve (0.58 microgram/g . h) less than cerebellum less than hypothalamus less than midbrain less than corpus striatum less than cerebral cortex (0.16 microgram/g . h).     

Effect of lead microparticles introduced into the respiratory system of the sensitivity of mice to Pasteurella multocida infection via aerosol]

Lead microparticles, resulting from the pyrolysis of organic lead used as an anti-knock agent in gasoline, were introduced into the lungs of Mice, during a short single exposure. When 6 microgram of lead were retained in the lungs (mean value per Mouse), the phagocytic ability of the pulmonary alveolar macrophages harvested 6 and 18 hrs. later, was significantly reduced. It was observed, in the same conditions, that the resistance of Mice to experimental infection by aerosolized Pasteurella multocida, was significantly reduced. When 3 microgram of lead were retained in the lungs, there was no significant difference between control and intoxicated Mice.     

Pharmacologic study of several alpha-adrenolytics

Six alpha-adrenoceptor blocking agents have been investigated in dogs and rats. 170 150 and 170 153 have been found the most potent of these agents. At low doses (0,1 microgram/kg) they reversed the pressor response to low doses of adrenaline (0,1 and 0,3 microgram/kg) and suppressed the response to high doses of adrenaline. They reduced the pressor response to noradrenaline. In addition, in dogs 170 150 increased the tachycardia caused by stimulation of the cardiac nerve. The compound prevented and reversed the inhibition caused by clonidine on the effects of cardiac nerve stimulation. 170 153 did not increase the tachycardia caused by cardiac nerve stimulation, but it prevented and reversed the inhibitory effects of clonidine on this stimulation. The results show that 170 150 and 170 153 are potent alpha-adrenoceptor blocking agents acting on both pre and post-synaptic alpha-adrenoceptors which could be interesting pharmacological tools.     

GLC determination of betahistine in serum

A gas chromatographic method was developed for the determination of betahistine in serum in the range of 0.6-6.0 microgram/ml.     

Drosophila enzyme-genetics: A table

Summary A method for the vacuum distillation of microgram amounts of substances is described.     

Alpha-fetoprotein in tumor-bearing mice assayed by particle agglutination inhibition.

Serum alpha-fetoprotein (AFP) in hepatoma BW7756-bearing mice was measured by a new particle agglutination inhibition test employing AFP adsorbed to charcoal particles. The AFP levels and tumor weights showed nearly parallel increases to means of 2633 microgram/ml and 5.2 g, respectively, 28 days after implantation.     

5-hydroxytryptamine induced changes in body temperature of newborn kittens and guinea-pigs and the effect of indomethacin thereon

During the first days of life 10 microgram i.c.v. 5-HT evoked a primary, short-lasting hyperthermia in kittens and hypothermia in guinea-pigs. In both species, a secondary late hyperthermia occurred that could be prevented by indomethacin pretreatment.     

Luteolytic action of LHRH in women]

Several subcutaneous administrations of 250 microgram of LHRH (4 or 5 adminstrations at 4-hourly intervals per day) between the 2nd and 7th day post-ovulation in 4 normal women led to early luteolysis as demonstrated by a fall in serum progesterone concentration and early onset (2 to 3 days earlier) of menstruation.     

Potentiating effect of aldosterone on the diuretic action of atrial extract

The typical stimulatory effect of a rat heart atrial extract on urinary water, sodium, potassium and kallikrein excretion is significantly increased by a previous administration of aldosterone (0.5 microgram/100 g b. wt) in the rat.     

Immunomodulating effects in vitro of a hydroxythiazolobenzimidazole in the absence of mitogenicity

Wy-13, 876, a hydroxythiazolobenzimidazole, enhanced in vitro antibody formation by mouse spleen cells immunized with sheep red blood cells. The optimal dose was 25--50 microgram/culture. The compound did not have a mitogenic effect at any dose.     

Endotoxin-induced acceleration of ovum transport in rabbits.

Salmonella enteritidis-Boivin endotoxin (1--20 microgram/kg) induced accelerated oviductal ovum transport in rabbits in a dose-related manner. Indomethacin prevented this effect. Levels of prostaglandin E and F in uterine vein blood increased following endotoxin injection.     

A novel method in enzyme immunoassay: maleimide derivative of hapten for enzyme coupling.

Meta-maleimidobenzoyl derivative of L-thyroxine methyl ester (MBTM) was synthesized and coupled to beta-galactosidase at molar ratio of over 5 to 1. More than 97% of the enzyme was found to be labeled with MBTM. A thyroxine enzyme immunoassay was carried out with sensitivity in 0-10 microgram/100 ml range.