Erythromycin pharmacokinetics in children after rectal and oral administration

Pharmacokinetics of erythromycin base was studied clinically in children not older than 14 years treated with new children dosage forms of the antibiotic i. e. 0.1 and 0.25 g enteric coated tablets and 0.06 and 0.125 g suppositories. It was noted that the new dosage forms were characterized by higher availability which was 2.5-3 times higher than that after using the erythromycin base tablets without the coating. Systematic increasing of erythromycin availability after the use of the rectal suppositories was observed with increasing of the children age. Absolute absorption in newborns, sucklings and children over 1 year amounted to 28, 36 and 54 per cent respectively.     

Role of formic acid in transformation of acetic and succinic acids in animal tissues

Acetic and succinate acids KoA acyl derivatives interacting with formate were displayed to produce alpha-ketoacids--pyruvate and alpha-ketoglutarate. These acids also interact with formate and make pyruvic and malate acids, while alpha-ketoglutarate, evidently, tricarboxy acids. Interaction of formate with acetic and succinate acids inspite of occurring out of the tricarbone cycle increases the latter metabolic functions.     

Prediction of the three-dimensional structure of aflatoxin of Aspergillus flavus by homology modelling

Aflatoxins are polyketide-derived secondary metabolites produced by Aspergillus spp. The toxic effects of aflatoxins have adverse consequences for human health and agricultural economics. The aflR gene, a regulatory gene for aflatoxin biosynthesis, encodes a protein containing a zinc-finger DNA-binding motif. AFLR-Protein three-dimensional model was generated using Robetta server. The modeled AFLR-Protein was further optimization and validation using Rampage. In the simulations, we monitored the backbone atoms and the C-α-helix of the modeled protein. The low RMSD and the simulation time indicate that, as expected, the 3D structural model of AFLR-protein represents a stable folding conformation. This study paves the way for generating computer molecular models for proteins whose crystal structures are not available and which would aid in detailed molecular mechanism of inhibition of aflatoxin.     

Formaldehyde metabolism in semicarbazide intoxication

Subchronic administration of semicarbazide in the experiment with the rats was used to reduce the formaldehyde level in the organism in order to reveal the interaction between formaldehyde metabolism and biochemical parameters, which define the oxidant-antioxidant system condition and NO metabolism. It has been found that under semicarbazide impact the generation of free radicals, ROS, nitrite and nitrate were enhanced while aldehydes level was reduced that resulted from not only semicarbazide effect like the aldehydes acceptor, but the formaldehyde synthesis slowdown and acceleration of its transformation into format as well. We suppose that formaldehyde plays certain role in the development of connective tissue pathology.     

Mapping the amino acid properties of constituent nucleoporins onto the yeast nuclear pore complex

Visualization of molecular structures aids in the understanding of structural and functional roles of biological macromolecules. Macromolecular transport between the cell nucleus and cytoplasm is facilitated by the nuclear pore complex (NPC). The ring structure of the NPC is large and contains several distinct proteins (nucleoporins) which function as a selective gate for the passage of certain molecules into and out of the nucleus. In this note we demonstrate the utility of a python code that allows direct mapping of the physiochemical properties of the constituent nucleoporins on the scaffold of the yeast NPC׳s cytoplasmic view. We expect this tool to be useful for researchers to visualize the NPC based on their physiochemical properties and how it alters when specific mutations are introduced in one or more of the nucleoporins. The code developed using Python is available freely from the authors.     

Possible Regulatory Effect of Lipid Peroxidation on the H+-ATPase Activity of the Plasmalemma under Stress Conditions

We studied the effects of high temperature and paraquat on the rate of lipid peroxidation and activity of the H⁺-ATPase in the plasmalemma fraction isolated from pea leaves. We demonstrated a heat-induced increase in both indices. When lipid-peroxidation was inhibited by pretreatment with butylated hydroxytoluene, a synthetic antioxidant, the H⁺-ATPase activity increased to a lesser extent than after heat shock without pretreatment. Treatment of plants with paraquat, a prooxidant causing an oxidative stress, resulted in a dramatic increase in lipid peroxidation and H⁺-ATPase activity. We suggested that the enhanced lipid peroxidation could be one of the causes for the H⁺-ATPase activation in the plasmalemma under stress conditions.     

Biosynthesis of butyric acid from cabbage stem and molasses by the strain Clostridium butyricum VKPM B-9619

The acidogenesis of the strain Clostridium butyricum VKPM B-9619 on synthetic medium SOL, a fermentative hydrolyzate of cabbage stem, and molasses as cheap sources of carbohydrate nutrition of micro-organisms, has been studied. The yield of butyric acid was no less than 43%. It was found that, in addition to hexoses, the strain ferments pentoses (xylose and arabinose), which enables the processing of wastes of pentosan- and cellulose-containing plant raw materials with the addition of molasses. The fermentation liquid of the strain can be used for the isolation of butyric acid by the ion exchange method.     

The Seasonal Dynamics of <Emphasis Type="Italic">Cystoseira crinita</Emphasis> Duby, 1830 (Fucales: Phaeophyceae)-Dominated Communities in the Northeastern Black Sea

The structure and seasonal dynamics of marine algal communities dominated by Cystoseira crinita Duby, 1830 were studied in the northeastern Black Sea at depths of 2, 5, and 10 m. Seasonal fluctuations were found to be mainly manifested in biomass changes of the dominant species C. crinita at depths of 2 and 5 m. No seasonal changes in the studied parameters of communities were found at a depth of 10 m. The mean annual production of C. crinita was 1472.3 g/m², with the maximum at a depth of 5 m (2148.1 g/m²). The minimum production was observed at a depth of 10 m. At all depths, the production of C. crinita was highest in the spring; this index had zero values in the fall and winter.