Biological activity of hydroxyanthraquinones and their glucosides toward microorganisms

Five mono- and dihydroxyanthraquinones as well as 12 of their glucosides (both free and acetylated) were tested with six different microbial species using the plate-diffusion method. None of the tested substances was active againstEscherichia coli, 15 of the 17 substances displayed an activity towardBacillus subtilis, Bacillus cereus, Candida albicans, Saccharomyces cerevisiae andStreptomyces aurecfaciens. Relationships between the substance type and biological activity are discussed.     

Effect of some antiestrogens and aromatase inhibitors on androgen induced sexual behavior in castrated male rats

The effect of antiestrogens (MER-25, ICI-46474, and cis-clomiphene) and aromatase inhibitors (5-α-androstanedione, metopirone, and aminoglutethimide) on androgen induced copulatory behavior was tested in sexually inexperienced castrated male tats. Daily injections of 1 mg testosterone (T) for 21 days induced sexual activity in most subjects (61% mounting). Daily pretreatment with MER-25 or cis-clomiphene at three dose levels did not block the behavioral response to T. ICI-46474 at the high dose level (1 mg/kg) elicited a significant depressory effect on the sexual behavior of the T treated castrated rats. A single injection of 6 mg testosterone propionate (TP) induced mounting behavior in 56% of the tested rats within 120 hr. Treatment with metopirone or 5 α-androstanedione (injections every 12 hr for 96 hr) did not inhibit the response to TP. By contrast, aminoglutethimide (5 or 15 mg every 12 hr for 96 hr) abolished the behavioral response to androgen.     

Interaction of ethidium bromide with the transport system for monovalent cations in yeast

Summary Ethidium was found to be taken up by yeast cells in a process that, at certain concentrations has the main following characteristics: a) a substrate is required; b) it presents cooperative kinetics, withn, according to the Hill equation 3; c) ethidium can be concentrated more than 100-fold; d) the uptake is inhibited by Ca²⁺; e) the uptake of the dye is inhibited by monovalent cations with a selectivity pattern similar to that observed in their transport by yeast; f) ethidium inhibits the uptake of K⁺, and, at concentrations up to about 250 m produces a competitive inhibition on the uptake of Rb⁺; and g) ethidium produces the same effects as K⁺ on respiration and the extrusion of H⁺. It is concluded that ethidium is taken up by yeast cells in a selective way by the same transport system normally employed for monovalent cation uptake.     

XY gonadal dysgenesis with female phenotype (author's transpl)]

In this paper, we are dealing with the study of a case of multiple somatic malformations, with external female genitals and 46 XY caryotype. The anatomical and histological study of the genital organs, allows us to verify the existence of internal genital organs; consisting essentially in tubes, bicornous uterus, a gonadal ligament in a normotopical position, Wolffian remains and the absence of a vagina. The external female genitals are completely normal. When we interpreted these findings, we paid special attention to the relation existing between the abnormal presence of the Wolffian remains, male genotype, and typical female genital structures. Taking account of the latest scientific advances concerning genital development, we considered the possibility of the existence of secretions of a "masculinizing" substance from the gonad, before its morphological differentiation, which was interrupted by an etiological undetermined noxa. When this evolution was arrested, together with the secretions of the masculinizing substance, the genital development continued normally for a female. The terminal teratogenic period for this malformation is situated from the 5th to the 6th week of gestation (human embryos from 11 to 14 mm., Streeter Horizon XVII).     

Cell wall enzymatic lysis of the yeast form of Pullularia pullulans and wall regeneration by protoplasts

During the process of degradation of the cell wall of the yeast form of Pullularia pullulans by the lytic system of Micromonospora chalcea samples were withdrawn at different times and observed under phase contrast and electron microscope. The progressive lysis of the walls reveals a fibrillar component inside the apparently amorphous wall. Freeze etched preparations of cells during the formation and regeneration of protoplasts show that the cellular membrane is split and this method allows the smooth external face of the membrane and other internal face covered by particles to be seen. The fact that the smooth face of the membrane is only visible during the preparation or the regeneration of protoplasts and very rarely when intact cells are fractured, suggests a strong adherence between cell wall and this external layer of the membrane. During the regeneration which takes place as in most of the yeasts and moulds, a special study of the extension of the cell wall is made and a possible mechanism for this extension of the regenerated cell wall is proposed.     

Synthesis of β-glucanase and other extracellular proteins by cells and protoplasts of the yeast Pichia polymorpha

The synthesis of β-glucanase either by cells or by protoplasts of the yeast Pichia polymorpha has been found to occur in the presence of 2-deoxy-d-glucose in the growth medium. On the other hand, the synthesis of typical extracellular proteins such as invertase and acid phosphatase is strongly affected by the presence of the drug. The degree of inhibition is, however, directly related to the 2-deoxy-d-glucose concentration.