Collagenolytic activity in several species of deuteromycetes under various storage conditions

The ability of deuteromycetes of the genera Penicillium, Aspergillus, and Botrytis to retain collagenolytic activity was studied after both 2 and 10 years of storage on a Czapek medium under a layer of mineral oil at 4 degrees C, as well as in silica gel granules at 20 and -60 degrees C. The enzymatic activity of several species, including Botrytis terrestris, Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum, was retained under both conditions of storage. Aspergillus repens retained enzymatic activity only if stored under a layer of mineral oil. The viability of conidia and the collagenolytic activity of Botrytis terrestris, P. janthinellum, P. chrysogenum, and Penicillium citrinum, maintained on silica gel for 10 years, depended on the storage temperature. The viability of the test strains improved after storage on a silica gel at -60 degrees C. A strain of Aspergillus repens lost its ability to dissolve collagen at various storage temperatures on the silica gel. The index of lysis for three strains of Penicillium deuteromycetes (Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum) increased after a 10-year storage on silica gel at -60 degrees C.     

Individual dynamics of the EEG running wave under various conditions of activity

In 25 healthy subjects at resting with their eyes closed and open, a current phase structure of the EEG was measured, i.e. a trajectory and velocity of oscillation spreading over the head surface in temporal-occipital area. Visual computer multiplication revealed stable individual specifics of the EEG "running wave" dynamics which were then confirmed independently proceeding from the statistical significance criteria. Some subjects had characteristic transversal modulations of the EEG waves (from the left fo the right and vice versa), other subjects manifested longitudinal modulations along the diagonal from the cortex left anterior areas to the right posterior those (in some of them) or along the same diagonal in the opposite direction (in others). When opening the eyes, the character of the EEG "running wave" undergoes dramatic changes. Among other parameters, a growth of the trajectory share occurs in occipital area along with acceleration of the "running wave" spreading on all other trajectories. Both effects are bound to each other and the sharper dynamics is specific for subjects characterised as sympathotonic those as compared with para-sympathotonic.     

Ultrastructural organization of the hypothalamic medial preoptic area and its changes under the effect of pyrogens

In order to study structural bases of central mechanisms of thermoregulation, a comparative electron microscopic analysis of various cellular groups in one of thermosensitive zones of the cat hypothalamic area--the medial preoptic area--have been carried out under conditions of experimental fever. The latter is produced by injection of pyrogen of bacterial origin--pyrogenal--to the animals. Pyrogenal, increasing the body temperature, produces a stimulatory effect on various cellular elements, first of all on leucocytes, monocytes and macrophages in the medial preoptic area, as well as on endotheliocytes of the terminal vessels. Under pyrogenal effect activation of microglial cells and pericytes also takes place, and as a result of the rearrangements, occurring in the structure, they change into macrophages. This is an evidence of their active participation in the immune protection of the brain. According to the data from other investigations, all these activated cells produce peptide interleukin-1, one of the mediators of fever and stimulator of the immune system. Pyrogenal is stated to produce a stimulating effect on the astroglia and on some neurons of the medial preoptic area, that respond with cytoplasm increase and accumulation of numerous organelles. The reactive changes at fever in some neurons of the medial preoptic area can demonstrate that they belong to the thermosensitive pool. A conclusion is made, concerning a complex effect of pyrogenal, that results in a cooperative response of a number of cellular systems of the organism.     

Ultrastructural changes in the pyrenoid of the lichenParmelia sulcata stored under controlled conditions

Summary Observations have been made on ultrastructural changes in pyrenoids of the algal cells in the lichenParmelia sulcata subjected to a range of controlled desiccation and rehydration regimes. Weaker staining of parts of the proteinaceous pyrenoid matrix, interpreted as damage, occurred within 48 hours of transfering moist thalli to 53% r.h. in a 12 hours light 12 hours dark (20°C 14°C) regime. No specific damage resulted from direct dehydration at 0% r.h. or on transfer after 48 hours from 53% r.h. to 0% r.h. Material stored dry under different conditions,e.g., 0%, 53% or 53% to 0% r.h., for 72 hours showed recovery of the pyrenoid matrix when rehydrated in water (30 minutes) or by storage at 100% r.h. for 24 hours. After storage at 53% r.h. or 0% r.h. for 3 months, damage was more extreme, being greater in material originally dried at 53% r.h. Recovery in water, to the original appearance, only occurred after rehydration for 24 hours at 100% r.h. After 3 months desiccation, damage, due to the initial 48 hours at 53% r.h. was still apparent. Severe damage involved expansion of the pyrenoid. As rehydration restored pyrenoids to their original dimensions, pyrenoid proteins probably became dispersed rather than degraded during desiccation.     

Influence of various concentrations of phenol and its derivatives on the activity of fish intestinal peptidases

The effects of phenol and its derivatives (4-chlorophenol, 4-nirophenol and 2,4-dinitrophenol) on the activity of peptidases in five species of fish differing in feeding modes have been studied. The power of the effects depends on the fish species and localization of the enzyme (mucosa or chyme). As a rule, in the in vitro conditions the phenols in concentrations of 0.06?0.5 μM/L considerably decreases activities of the intestinal peptidases in bream; silver bream; and, especially, in pike. In some cases, phenol and its derivatives induce an inconsiderable increase in peptidase activities. In zander and perch, in fact, no changes in the enzymatic activity under impact of phenols are observed. It is suggested that the effect of phenol and its derivatives depends to a high extent on the species specificity of peptidases: in the fish of fam. Percidae, the enzymes are relatively tolerant; in fam. Cyprinidae and Esocidae, they are sensitive to the studied toxicants.