Phosphoinositidase C activities sensitive to purine and pyrimidine nucleotides have been identified earlier in ampulla from Rana ridibunda semicircular canal. The aim of this study was to characterize the pharmacological properties of other P2 receptors borne by this structure. A microassay was developed to measure the binding of [35S]adenosine 5'- O-(2-thiodiphosphate) ([35S]ADPβS) to a few am...

The enzyme 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) catalyzes biosynthesis of progesterone (P) and all precursors of glucocorticoids, mineralocorticoids, androgens, and estrogens. Despite the broad interest raised by neurosteroids, the cellular localization of 3 beta-HSD has never been investigated in the brain. We took advantage of the availability of an antis...

BACKGROUND Antibiotics are usually assumed as secondary metabolites produced during the idiophase of microbial growth, which can kill or inhibit the growth of other microorganisms. Nowadays, indiscriminate use of antibiotics has resulted in resistant microorganisms. Therefore, screening researches on products with antimicrobial activities are necessary. OBJECTIVES To find new antibiotics to d...

In higher vertebrates the cytoskeleton of glial cells, notably astrocytes, is characterized (a) by masses of intermediate filaments (IFs) that contain the hallmark protein of glial differentiation, the glial filament protein (GFP); and (b) by the absence of cytokeratin IFs and IF-anchoring membrane domains of the desmosome type. Here we report that in certain amphibian species (Xenopus laevis, ...

Hydrogen and some divalent cations block Na channels in a voltage-dependent manner (Woodhull 1973; Ulbricht and Wagner 1975; Mozhayeva et al. 1981, 1982a; Begenisich and Danko 1983). The potential-dependence of this blockage suggests that the binding site for blocking ions is situated in the pore at some fractional distance (<5) from the outside (Woodhull 1973). Alkaloid aconitine has been show...

In this study, two mountain frogs (Rana camerani and Rana macrocnemis) were collected in the Antalya Province in south-western Turkey during 2001 and 2002 and were examined for helminths. Out of 15 Rana camerani, 10 (66.7%) were infected with 1 or more helminths and out of 20 Rana macrocnemis, 17 (85%) were infected with 1 or more helminths. The helminth fauna of Rana camerani included 4 specie...

immune genes of the major histocompatibility complex (mhc) are among the most polymorphic genes in the vertebrate genome. due to their polymorphic nature, they are often used to assess the adaptive genetic variability of natural populations. this study describes the first molecular characterization of 13 partial mhc class iib sequences from three european ranid frogs.  the utility of previously...

conclusions this study showed that some properties of antimicrobial substances produced by the ga strain differed from other peptide antibiotics produced by the genus bacillus such as bacitracin, which increases the likelihood of its novelty. results the isolated bacterium was identified as a new strain of bacillus atrophaeus. the antimicrobial substance exhibited heat stability between 25ºc an...