Cestode lysosomes

By differential centrifugation method a lysosomal fraction was obtained from five species of cestodes, which possesses the highest specific activity of acidic phosphatases as compared to other subcellular fractions. By isopyknic centrifugation in the density gradient of saccharose the lysosomal fraction is divided into primary and secondary lysosomes. Lysosomes of cestodes are similar to those of vertebrate animals in the character of fractional distribution of acidic phosphatase, sedimentation abilities and sensitivity of membranes to triton X-100.     

A Comparative Characterization of the Mitochondrial Genomes of Paramoeba aparasomata and Neoparamoeba pemaquidensis (Amoebozoa,Paramoebidae)

Marine amebae of the genus Paramoeba (Amoebozoa, Dactylopodida) normally contain a eukaryotic endosymbiont known as Perkinsela‐like organism (PLO). This is one of the characters to distinguish the genera Neoparamoeba and Paramoeba from other Dactylopodida. It is known that the PLO may be lost, but PLO‐free strains of paramoebians were never available for molecular studies. Recently, we have described the first species of the genus Paramoeba which has no parasome—Paramoeba aparasomata. In this study, we present a mitochondrial genome of this species, compare it with that of Neoparamoeba pemaquidensis, and analyze the evolutionary dynamics of gene sequences and gene order rearrangements between these species. The mitochondrial genome of P. aparasomata is 46,254 bp long and contains a set of 31 protein‐coding genes, 19 tRNAs, two rRNA genes, and 7 open reading frames. Our results suggest that these two mitochondrial genomes within the genus Paramoeba have rather similar organization and gene order, base composition, codon usage, the composition and structure of noncoding, and overlapping regions.     

Interaction of sex steroids with proteins from the soluble fraction of swine and cattle liver (a preliminary analysis)]

The interactions of [3H]estradiol, [3H]testosterone and [3H]progesterone with soluble proteins from porcine and calf liver were studied. The specific binding of [3H]progesterone and [3H]testosterone in calf liver cytosol seems to be due to serum transcortin or its intracellular precursor (analog). Contrariwise, the specific binding of [3H]progesterone observed in porcine liver cytosol was absent in the serum. This binding was characterized by slow association and dissociation dynamics, moderate affinity for the [3H]-ligand and a high binding capacity. The structural determinants of the ligands were studied by competitive inhibition of the [3H]-ligand binding. The delta 4-3-keto group in the steroid A-ring was found to be the most important determinant. An intensive metabolism of [3H]progesterone was observed during its incubation with cytosol (data from thin-layer chromatography). A 3H-metabolite (presumably, 20 beta-dihydroprogesterone) was predominant in the bound ligand fraction. The data obtained suggest that proteins of a steromodulin type are widely distributed in the mammalian liver.     

Primary cultures of enzyme-isolated cells from normal and atherosclerotic human aorta

A technique has been developed for isolating cells from the intimal and medial layers of the human aorta by enzymatic dispersion. After mechanical separation of intima, media and adventitia the intima and the media were dispersed by collagenase and elastase. Enzyme-isolated cells seeded in the culture with at a frequency of 30 to 50%. In the primary culture differentiated aortic cells were morphologically heterogenous. It was possible to define four main types of cells according to their shape: polygonal, elongated, asymmetrical and stellate. Polygonal and stellate cells are found only in cultures of grossly normal intima, whereas elongated and asymmetric cells are found in practically all cultures. The ratio of elongated to asymmetric cells in cultures obtained from healthy aorta and atherosclerotic plaque is more or less the same at approximately 3:1. In cultures of fatty streaks the proportion of asymmetric cells exceeds 50%. Using immunofluorescence, all four types of cell were identified as smooth muscle cells. The possible reasons for the cellular polymorphism in primary culture and the prospects of utilizing this culture for the study of cellular aspects of atherosclerosis' pathogenesis are discussed.     

Effect of salvin on the synthesis of macromolecules in Staphylococcus aureus 209P

The effect of salvin and its active component, carnazolic acid, on the synthesis of macromolecular compounds in the cells of S. aureus 209P was studied. It was shown that the inhibitory action of salvin on the synthesis of peptidoglycane in the culture was defined by the presence of carnazolic acid in its composition. In the bactericidal concentration, carnazolic acid was twice as less active as salvin and inhibited incorporation of labeled precursors into RNA and protein. The findings grounded the conclusion that some nonidentified components of salvin with low antimicrobial activity contained in it in insignificant quantities had an additional inhibitory effect on the process. Comparative study of salvin and antibiotics with the known mechanisms of action such as benzyl penicillin or chloramphenicol revealed a certain similarity in the action of salvin and benzyl penicillin on incorporation of labeled precursors into the macromolecular compounds of S. aureus 209P.