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The effects of a new derivative of benzimidazole (K-134) in doses of 5 and 50 mg/kg on the spermatogenesis and fertilizing ability of spermatozoa were studied on male rats. It was found that 2-month course treatment with the studied substance enhances the producing ability of the spermatogenic epithelium and improves fertilizing ability of spermatozoa.

The representatives of Asterozoa (Asteroidea, Echinoidea, and Ophiuroidea) have a similar struc� tural plan of the axial complex with minor differences within each class; this structural scheme substantially differs from that in Crinozoa and Holothurozoa. The axial complex consists of the coelomic organs and the haemocoel (blood) structures, which are morphologically and functionally integral. The coelomic organs are the stone canal, axial coelom, perihaemal coeloms (axocoel perihaemal ring and somatocoel perihaemal ring), water ring, and pericardial and genital coeloms. These organs are closely associated with the epigastric and hypogastric coeloms and with the perioral coelomic ring. The haemocoel structures of the axial complex include the oral haemal ring, heart, axial organ, genital haemal ring, and gastric haemal ring. The epineural canals of echinoids and ophiuroids are of a noncoelomic nature. They are formed by the invagination of the ectoneural cord and closing of the epidermis above it. The possible functions of the axial complex in Astero� zoa are blood circulation and excretion.

The axial complex is one of the most characteristic features of echinoderms. Descriptions of it in classic papers are contradictory. The present paper provides data on the microscopic anatomy of the axial complex in the starfish Asterias rubens restudied using histological techniques. The axial complex is located in the wall of the interradius CD; it is elongated in the oral-aboral direction. The stone canal in its aboral end communicates with the axial coelom; in its oral end, it communicates with the water-vascular ring canal. The axial coelom opens to the madreporic ampulla of the stone canal on its aboral end and to the axocoel perihemal coelom on the oral end. The axial organ is formed by the blood vessel network between the basal laminae of the pericardial, axial, and perihemal coelothelia. In Asterias rubens, the heart is a part of the axial organ, which divides the latter into the true axial and pericardial parts. The extensive axial (oral) part of the axial organ opens to the oral blood ring, which is situated in the mesentery between the perihemal coeloms. The smaller, pericardial (aboral), part of the axial organ opens to the hemocoel of the body wall. The genital coelom represents an integral part of the axial complex since one of the five gonad blood lacunae located in the interradius CD communicates with the heart and axial organ vessels. The mistakes and inaccuracies extant in the scientific literature about the anatomy of the asteroid axial complex are discussed. The blood circulation into the axial organ occurs predominantly from the aboral side to the oral side of starfish.

Earlier we have shown that in epithelial cells of the frog urinary bladder under action of bacterial lipopolysaccharides (LPS) there is activated expression of inducible NO-synthase (iNOS) and there is increased the NO production, which can play an important role in providing protective cell reactions form pathogens. The goal of the present work consisted in study of cyclooxygenase (cOG) products and mechanisms of their regulatory effect on expression of iNOS under action of LPS. In experiments on urinary bladder epithelial cells on the frog Rana temporaria it has been shown that incubation of the cells for 21 h with LPS leads to a rise in production of PGE2 and nitrites, stable NO metabolites. Inhibitor of iNOS 1400W decreased sharply production of nitrites, but did not affect the PGE2 level. Both the basal and the LPS-stimulated level of PGE2 and nitrites were inhibited in the presence of selective cOG inhibitors SC-560 (cOG-1) and NS-398 (cOG-2). The IC50 value amounted to 90, 220 and 470 μM for NS-398, SC-560, and diclofenac (unspecific inhibitor of both isoforms), respectively. PGE2 and butaprost, the EP2-receptor agonist, but not agonists of EP1/EP3 or EP1 receptors, partially eliminated the inhibitory action of diclofenac on production of nitrites. Action of PGE2 was accompanied by an increase in the intracellular cAMP. Analysis of expression of iNOS mRNA in the epithelial cells incubated with LPS or LPS + inhibitor of cPG has shown the LPS-stimulated rise in expression of iNOS mRNA to decrease sharply in the presence of SC-560 or NS-398. Thus, the epithelial cells of the frog urinary bladder have the effectively functioning system of the congenital immune protection against bacterial pathogens, the most important component of this system being PGE2 and NO. Analysis of mechanisms of regulatory interactions of cOG and iNOS indicates that in this cell type the main regulators of iNOS expression and of the nitrogen oxide level are products of the cOG catalytic activity.

We have shown previously that endogenous nitric oxide (NO) in frog urinary bladders modulates the influence of arginine-vasotocin on the increase in the osmotic water permeability of the bladder epithelium. The goal of the present work was to obtain a primary culture of epithelial cells from a frog urinary bladder in order to study in vitro the cellular activity of NO-synthase (NOS) and its regulation. The best conditions for cultivating the cells turned out to be with the use of a modified L-15 medium containing 10% fetal bovine serum and gentamicin (40 μg/ml) at room temperature. Under these conditions, at least 50% of the cells preserved their viability for 8 days. The NOS activity was estimated from the accumulation of nitrites (NO 2 − ) in the cultivation medium; the amount of NO 2 − in the presence of nitro-L-arginine methyl ester (L-NAME), an inhibitor of all types of NOS, was considered unspecific and was subtracted from each value. The NO 2 − accumulation was linear in time for three days of cultivation and was inhibited by 1400W, an inducible NOS (iNOS) inhibitor, or by 7-nitroindazole, an inhibitor of constitutive NOSs, at concentrations of 5–50 and 10–200 μM, respectively. One-day incubation of the cells in the medium with low doses of gentamicin (1 or 2 μg/ml) led to a marked increase in the amount of bacteria in the cultivation m5 mM edium identified as E. coliand Acinetobacter sp. An addition of 5 mM L-NAME to the cultivation medium increased the amount of the bacteria by 1.5-and 2.5-fold in the presence of 2 and 1 μg/ml gentamicin/ml, respectively. Thus, the epithelial cells of frog urinary bladders have the NO-dependent antibacterial effect, which seems to be the result of enhanced iNOS expression. The obtained data indicate that the primary culture of the epithelial cells from frog urinary bladders is a prospective model for studying the role of NO and the regulation of NOS activity, which is of particular interest for studying protective NO effects in epithelial tissues.

The activity of arginase converting arginine into ornithine and urea is of particular interest among many factors regulating NO production in the cells. It is known that by competing with NO-synthase for common substrate, arginase can affect the NO synthesis. In the present work, the properties of arginase from the frog Rana temporaria L. urinary bladder epithelial cells possessing the NO-synthase activity were characterized, and possible contribution of arginase to regulation of NO production by epithelial cells was studied. It has been shown that the enzyme had the temperature optimum in the range of 55-60 degrees C, K(m) for arginine 23 mM, and V(max) about 10 nmol urea/mg protein/min, and its activity was effictively inhibited by (S)-(2-boronoethyl)-L-cysteine (BEC), an inhibitor of arginase, at concentrations from 10(-6) to 10(-4) M. The comparison of arginase activity in various frog tissues revealed the following pattern: liver > kidney >> brain > urinary bladder (epithelium) > heart > testis. The arginase activity in the isolated urinary bladder epithelial cells was 3 times higher than that in the intact urinary bladder. To evaluate the role of arginase in the regulation of NO production, epithelial cells were cultivated in the media L-15 or 199 containing different amounts of arginine; the concentration of NO2-, the stable NO metabolite, was determined in the culture fluid after 18-20 h of cells incubation. The vast majority of the produced nitrites are associated with the NOS activity, as L-NAME, the NOS-inhibitor, decreased their accumulation by 77.1% in the L-15 medium and by 80% in 199 medium. BEC (10(-4) M) increased the nitrite production by 18.0 % +/- 2.7 in the L-15 medium and by 24.2 +/- 3.5 in the 199 medium (p < 0.05). The obtained data indicate a relatively high arginase activity in the frog urinary bladder epithelium and its involvement in regulation of NO production by epithelial cells.

The production of superstrong and durable heat-treated railroad wheels fromT steel is considered. Aspects of heat treatment are described, and the macrostructure, microstructure, and mechanical properties of the wheels are investigated.

The effect of the twist rate on the physicomechanical properties of complex Oxalon thread was investigated. It was found that in processing samples of complex Oxalon thread on a doubler-twister, the thread is more subject to deformation than thread made on a twist counter and thus has a lower elongation at break. The optimum process parameters for processing Oxalon sewing thread of 29 tex × 2 × 2 structure are determined.

It is shown that in technically suitable conditions for shaping blanks by centrifugal casting, the deposition of the particles occurs with a streamline schedule, and the coarse fractions are deposited during acceleration of the rotation of the mold. The main factor influencing the density of the finely dispersed blanks is the duration of rotation, and for systems containing coarse filler, centrifugal acceleration. Regulating the dimensions (wall thickness) of the blank is possible by altering the concentration of solid phase in the slip and the degree of filling of the mold with it.

A study has been made of35CI NQR spectra of a series of 3-substituted 1-dichlorophosphocyladamantanes. The mechanism of increased conductivity of the adamantane nucleus is examined within the framework of a quasi-π-electron approach.

Сердепные гликозиды с в 19-OM no-ложении молекулы оказались наиболее зффективными ингигиторами натриевого наоаса клеток кожи лягшки. Налицие ацетильного радикала увелицвало ингибирумуп способнность гликозида; агликон — оуабагенин оказался самым слабым инибитором.