Secretion of organic acids and bases by the kidneys of marine teleosts

In the experiments performed on kidneys of 5 species of marine Teleostei, morphological peculiarities in secretion of 8 fluorescent organic acids (uranin, primulin, tripaphlavin, erythrosin etc.) and in 5 organic bases (rhodamin C, auramin etc.) have been studied. At a very low concentration in the incubation medium--about 0.005 mg/ml--the substances mentioned penetrate into the epithelial cell of the canaliculus; its weak fluorescence appears, and soon they begin to be excreted in great amount through the apical part of the plasmolemma and accumulated in the canalicular lumen. All the substances studied accumulate in the cell and only some of them (uranin, primulin, titanic yellow, etc.) are secreted into the canalicular lumen. Penicillinum and probenecide inhibit penetration of the organic acids into the cell through the basal membrane. Uranin secretion into the canalicular lumen is inhibited in the presence of furocemid; amilorid, magnium and sulfate ions do not influence secretion of the organic acids. Secretion of the organic bases does not change when paraaminohippuric acid and furocemid are added to the medium, but it decreases when concentration of magnium ions increases.     

Catecholamine content and acetylcholinesterase activity in the brain of rats exposed to lasers

The catecholamine content was quantitated and acetylcholinesterase activity determined in rat brain locally exposed to laser radiation. It was shown that the adrenaline/noradrenaline ratio changed in the tissues under study and the cholinergic system was involved in the abscopal effect of laser radiation.     

Pifithrin-α Inhibits Neural Differentiation of Newborn Cells in the Subgranular Zone of the Dentate Gyrus at Initial Stages of Audiogenic Kindling in Krushinsky–Molodkina Rat Strain

Journal of Evolutionary Biochemistry and Physiology - One of the main challenges of modern neurobiology is finding approaches to prevent structural abnormalities in the brain, specifically, in the...     

The environmental fate and behaviour of antifouling paint booster biocides: A review

Antifouling paint booster biocides are a group of organic compounds added to antifouling paints to improve their efficacy. They have become prevalent since the requirement for alternative antifouling paints formulations for small boats (< 25 m). This need followed a ban on the use of triorganotin biocides in antifouling paints for small boats, in the late 1980's. Worldwide, around eighteen compounds are currently used as antifouling biocides, viz. benzmethylamide, chlorothalonil, copper pyrithione, dichlofluanid, diuron, fluorofolpet, Irgarol 1051, Sea‐Nine 211, Mancozeb, Polyphase, pyridine‐triphenyl‐borane, TCMS (2,3,5,6‐tetrachloro‐4‐methylsulfonyl) pyridine, TCMTB [2‐(thiocyanomethylthio)benzothia‐zole], Thiram, tolyfluanid, zinc pyrithione (ZPT), ziram and Zineb. Any booster biocide released into the environment is subjected to a complex set of processes. These processes include transport mechanisms, transformation, degradation, cross media partitioning, and bioaccumulation. This paper reviews the fate and behaviour data currently available in the public domain concerning antifouling paint booster biocides.     

Covalent binding of Cys142 from SsoII methyltransferase with DNA duplexes, containing a phosphoryldisulfide internucleotide group

DNA duplexes containing a single phosphoryldisulfide link in place of the natural internucleotide phosphodiester bond were employed in affinity modification of Cys142 in cytosine-C5 DNA methyltransferase SsoII (M.SsoII). The possibility of duplex-M.SsoII conjugation as a result of disulfide exchange was demonstrated. The crosslinking efficiency proved to depend on the DNA primary structure, modification position, and the presence of S-adenosyl-L-homocysteine, a nonreactive analog of the methylation cofactor. The SH group of M.SsoII Cys142 was assumed to be close to the DNA sugar-phosphate backbone in the DNA-enzyme complex.     

Functional evolution of two subtly different (similar) folds

Background

The function of proteins is a direct consequence of their three-dimensional structure. The structural classification of proteins describes the ways of folding patterns all proteins could adopt. Although, the protein folds were described in many ways the functional properties of individual folds were not studied.

Results

We have analyzed two β-barrel folds generally adopted by small proteins to be looking similar but have different topology. On the basis of the topology they could be divided into two different folds named SH3-fold and OB-fold. There was no sequence homology between any of the proteins considered. The sequence diversity and loop variability was found to be important for various binding functions.

Conclusions

The function of Oligonucleotide/oligosaccharide-binding (OB) fold proteins was restricted to either DNA/RNA binding or sugar binding whereas the Src homology 3 (SH3) domain like proteins bind to a variety of ligands through loop modulations. A question was raised whether the evolution of these two folds was through DNA shuffling.     

Cross adaptation of potato plants to low temperatures and potato cyst nematode infestation

Effect of short-term (2 h a day) and long-term (6 days) exposure to low temperature (5°C) on cold tolerance was investigated in two cultivars of potato (Solanum tuberosum L.): resistant (Sudarynya) and susceptible (Nevskii) to potato cyst nematode (Globodera rostochiensis Woll.). The extent of their infestation and changes in the expression of the genes of resistance to nematode (H1 and Gro1-4) were also analyzed. In both cultivars, exposure to low temperature enhanced cold resistance of potato plants. Enhancing cold resistance of cv. Sudarynya induced by a short-term exposure to chilling did not affect the extent of nematode infestation, whereas in susceptible cv. Nevskii, the extent of infestation decreased by almost three times. The level of expression of H1 gene in the leaves of the susceptible cultivar rose almost twofold both after short-term and long exposure to chilling, while in the resistant cultivar, gene expression increased only after a short-term effect of cold. The level of Gro1-4 gene expression increased after both temperature treatments only in the resistant cv. Sudarynya. Thus, the expression of genes for potato resistance to nematode infestation became more active in the susceptible cultivar as regards the gene H1 and in the resistant cultivar, regarding the gene Gro1-4. In the nematode-susceptible cv. Nevskii, the level of infestation decreased and cold resistance increased, apparently indicating cross adaptation to two factors of different nature.     

The dynamic of breathing biomechanics and intrathoracic hemodynamics parameters during microgravity modeling

In ground-based model of the hemodynamics effects of weightlessness, the intersystem relation of breathing and circulation was investigated during inspiration and expiration separately in anesthetized catz. It's shown that the dynamics of central venous pressure, esophageal pressure and filling pressure of the heart during inspiration in supine and head-down tilt position has obvious similarity to those which hypothetically can be present in microgravity. The results suggest that intrathoracic hemodynamics during inspiration in supine and head-down position may be an adequate ground model for investigation of weightlessness influences on intrathoracic circulation.     

A Comparative Analysis of Stachybotrys chartarum Strains Isolated in Russia

This work deals with a comparative analysis of Stachybotrys chartarum strains isolated from various artificial cellulose-containing materials and natural substrates in geographically distant regions of Russia. The analysis included determination of the spore size; the strain toxicity to Paramecium caudatum; the strain resistance to the fungicides Benomil, Olilen, and Tilt; and the PCR study of the genome structure with the aid of a primer that was complementary to the core sequence of the SINE retrotransposon. It was found that some of the strains that were isolated from different areas and from different substrates differ in their toxicity, fungicide resistance, and genome structure. PCR analysis showed the absence of any correlation between the genome structure, the strain properties, the geographic area, and the substrates from which the strains were isolated. The pheno- and genotypic diversity of the strains and their different vegetative compatibility suggest the existence of an intraspecies diversity of the S. chartarum strains that were isolated in different geographic areas. The absence of any correlation between the pheno- and genotypic properties of the strains and the substrates from which they were isolated implies that the colonization of artificial substrates by S. chartarum occurred occasionally from natural habitats. The S. chartarum populations that live on artificial substrates are unlikely to have their own evolutionary history.