The New Data on the Serotonin and FMRFamide Localization in the Nervous System of Opisthorchis felineus Metacercaria.

BACKGROUND: Trematoda Opisthorchis felineus Rivolta, 1884 is the causative agent of dangerous parasite disease-opisthorchiasis, widespread in the Russian Federation. The details of the neuroanatomical localization of the serotoninergic and FMRFamidergic neurotransmitter elements as well as their functional roles remain not studied enough in both adult and larval forms of O. felineus. The studies in this area are important in term of the development of a new pharmacological strategy of the struggle with the causative agent of opisthorchiasis affecting the neuronal signal substances and the function of its nervous system. PURPOSE: The aim of this work was the immunocytochemical study of the neurotransmitters serotonin (5-HT, 5-Hydroxitryptamine) and neuropeptide FMRFamide localization in the nervous system of the opisthorchiasis causative agent-O. felineus metacercaria. To study the relationship between the detected neurotransmitters and the muscular elements of the parasite, the muscle staining was carried out simultaneously using fluorophore-conjugated phalloidin. METHODS: The localization of 5-HTergic and FMRFamidergic nerve structures was determined by immunocytochemical method. The staining samples were analyzed using a fluorescent and confocal laser scanning microscopies. RESULTS: The new data on the presence and distribution of the serotonin-immunopositive (IP)- and FMRFa-IP components in the central and peripheral departments of the nervous system of  O. felineus metacercaria has been obtained. Besides that a number of the new anatomical details of the nervous system organization and of the innervation of the organs and tissues in the investigated parasite have been revealed. CONCLUSION: The data obtained on the presence and localization of the 5-HTergic and peptidergic (FMRFamide) components in central and peripheral departments of the nervous system of O. felineus metacercaria elaborated and expanded the existing information about the nervous system as well as the innervations of the tissues and organs in the causative agent of opistchorchiasis.

Fluorescent analysis for bioindication of ozone on unicellular models.

Unicellular model plant systems (vegetative microspores of horsetail Equisetum arvense and pollen of six plant species Corylus avellana, Dolichothele albescens Populus balsamifera, Salix caprea, Saintpaulia ionantha, Tulipa hybridum, on which autofluorescence and fluorescence after histochemical treatment studied, have been represented as bioindicators of ozone. It has found that low doses of ozone 0.005 or 0.008 µl/l did not affect or stimulate the autofluorescence of the samples with the ability to germinate in an artificial medium. In higher ozone concentrations (0.032 µl/l) either the decrease in the intensity of the emission or changing in the position of the maxima in the fluorescence spectrum (new 515-520 nm maximum characteristic for the green-and yellow area has appeared) were observed. In dose of 0.2 µl/l, higher than above the threshold of danger to human health, autofluorescence in all samples fell down to up to zero, and there was no the ability to germinate. In this case the formation of lipofuscin-like compounds fluoresced in blue with maxima from 440 to 485 nm was observed. Stress metabolites, known as neurotransmitters biogenic amines, were found in treated cells as determined on the characteristic fluorescence at 460-480 nm in the samples after a specific histochemical reactions for catecholamines (with glyoxylic acid) or for histamine (with o-phthalic aldehyde). Increased intensity of the emission under the treatment with ozone (total doses from 0.012 to 0.032 µl/l) was associated with an increase in the concentrations of catecholamines and histamine. The fluorescent analysis on undamaged cells-possible bioindicators of ozone can be useful in ecomonitoring for earlier warning about health hazardous concentrations of this compound in the air.

[On peculiarities of temperature dependences of water spectra in the terahertz frequency domain].

We analyzed spectra of light and heavy water at temperatures from 4 up to 50 degrees C in a frequency range of 0.15 to 6.5 THz. It was shown that the amplitude of high-frequency relaxation absorption band with its maximum at 0.5 THz extends with increasing, temperature and this temperature dependence for light water has a marked feature at 35-40 degrees C as a sharp growth. This fact is noteworthy because this range corresponds to physiological values of a body temperature of the warm-blooded organisms. At the same time, the analogous temperature dependence for heavy water in the considered temperature range lacks this particular feature. Thus, the water with its properties differs significantly not only from other fluids, but also from its own isotopologues.

Fusion and endocytosis of anionic liposomes with Ehrlich ascitic carcinoma cells.

Polyethylene glycol 300 and low pH of the incubation medium initiate fusion of anionic lipid liposome membranes with Ehrlich ascitic carcinoma cell membranes. Some liposomes are endocytosed in cells and are distributed near the inner surface of the membrane. Liposome membranes spontaneously fuse with the cells under certain conditions.

Sarcomere structures in the rabbit psoas muscle as revealed by fluorescent analogs of phalloidin.

The fluorescent analogs of phalloidin (rhodamine- and fluorescein-phalloidin) bind tightly to the skinned fibres of rabbit psoas muscle at essentially the same sites as phalloidin and mainly stain the known regions of actin localization in the sarcomere: the thin filaments and Z bands. On both sides of the Z bands, unstained zones were observed, suggesting the presence of proteins tightly bound to the thin filaments. In myofibrils which are stretched to such an extent that the actin and myosin filaments do not overlap, stained bands could also be seen at the myosin-band border, which suggests the localization of actin at these sites.

The fine structure of luminescence spectra of azurin.

The spectra of azurin absorption, fluorescence, phosphorescence and fluorescence excitation have been measured in aqueous solutions at ordinary and liquid nitrogen temperatures. The fluorescence spectra of azurin even at ordinary temperatures have a well resolved fine vibrational structure. The frequency analysis reveals practically the same wave number distances between the main structure peaks in fluorescence spectra at room and low temperatures and in phosphorescence spectra. The comparison of the protein absorption and excitation spectra shows that all the energy absorbed by tyrosine residues is transferred onto indole chromophore. These data suggest an unusual tryptophan environment in this protein, which is characterized by the absence of any hydrogen bonding or other polar interaction of tryptophan with its environment. The problem of the possibility of contributions of two electronic transitions (1La in equilibrium A and 1Lb in equilibrium A) in absorption and emission spectra of azurin tryptophan arising from their mirror symmetry is discussed.