Effects of 4-methyluracil and carnosine on healing of skin wounds in rats

In experiments in vivo and in vitro the authors studied antioxidative properties of 4-methyluracil and carnosine, their capacity to inhibit sex and accelerate healing of skin wounds. 4-methyluracil and carnosine discover almost the same capacity to decrease in the tissues of the wound and the blood serum in the formation of various intermediate products of free radical oxidation. Data are given on the study of the dynamics of wound healing after a 5-day treatment with equimolar quantities.     

Optimal Number of Embryos for Transplantation in Obtaining Genetic-Modified Mice and Goats

Russian Journal of Developmental Biology - The technology of creating genetically modified animals (placental mammals) by microinjection into the pronucleus of a fertilized egg suggests, as one of...     

Acoustic Analysis of Signals in Mammals

Spectral-prosodic characteristics of signals were analyzed synchronously with the main frequency for 32 mammals and one reptile using a KAZ-01 complex sound analyzer. The method of phoneme analysis was adapted for analysis of the signals. The main features of signaling in mammals have been revealed, which differed from those in birds and humans: low frequency range, low fundamental frequency, small number of local maxima, small frequency distance between them, and a significant amount of local maxima with zero energy.     

Fractionation of "tricholysine" by isoelectric focusing

A possibility to fractionate fibrinolytically and thrombolytically active complex "tricholysin" into five components, differing in iso-points and in enzymatic activity, is demonstrated by means of isoelectric focusing using ampholine solution within pH range 3.0-10.0. Homogenous fraction IV (isopoint 6.8-7.0) has a low caseinolytic activity and a high specific fibrinolytic and esterase activities. This fraction is characterized with a high ability of plasminogen activation. Serine, threonine, alanine and valine are found to prevail in amino acid composition of the fraction IV, its molecular weight being 39000.     

Various properties of ribonucleotide reductase from rat liver mitochondria]

Three fractions of mitochondria (light, heavy and intermediate) from normal and regenerating rat liver ( in 15, 24 and 48 hours after partial hepatectomy) were isolated by means of differential centrifugation. Heavy mitochondrial fraction was shown to have a higher CDP-reductase activity than light mitochondria. The activity of the procces of ribonucleotides reduction in the mitochondria was shown to depend on the tissue functional state and it was maximal in 24 hours after partial hepatectomy.     

Mitochondrial thymidine kinase and ribonucleotide reductase from rat liver and rat hepatoma 27]

Fractions of heavy and light mitochondria are isolated from homogenates of homologous rat tissues (intact liver, regenerating liver within 24 hours after hepatectomy and 27 hepatoma) by means of differential centrifugation. It is found that tumour mitochondria have higher heterogeneity and lower buyoant density than mitochondria from normal hepatocytes. The activity of two enzymes of DNA precursors synthesis (ribonucleotide reductase and thymidine kinase) in subcellular fractions is demonstrated to correlate with the tissue growth rate. A single injection of cyclic AMP into hepatectomised rats resulted in the retardation of the regeneration process, and the activity of both enzymes reached its normal level in all the fractions studied after 24 hours after the operation. Thymidine kinase and ribonucleotide reductase are located mainly in the mitochondrial matrix, however, pronounced enzyme activity is observed also in membrane fractions. The activity of the enzymes in the fraction of external mitochondria membranes in rapidly growing tissues is 2--3 times as high as in the same fraction from normal rat liver.     

Comparison of Species-Specific Bird Signals and Human Speech

We carried out a comparative study of spectral-prosodic characteristics of bird vocalization and human speech. Comparison was made between the relative characteristics of the fundamental frequency and spectral maxima. Criteria were formulated for the comparison of bird's signals and human speech. A certain correspondence was found between the vocal structures of birds and humans. It was proposed that in the course of evolution, man adopted the main structural principles of his acoustic signalling from birds.     

Decrease in pool of T lymphocytes with surface phenotypes of effector and central memory cells under Influence of TCR transgenic β-chain expression

Peripheral T lymphocytes can be subdivided into naive and antigen-experienced T cells. The latter, in turn, are represented by effector and central memory cells that are identified by different profiles of activation markers expression, such as CD44 and CD62L in mice. These markers determine different traffic of T lymphocytes in the organism, but hardly reproduce real antigenic experience of a T lymphocyte. Mechanisms of homeostasis maintenance of T lymphocytes with different activation phenotypes remain largely unknown. To investigate impact of T cell receptor (TCR) transgenic chains on formation of T lymphocytes, their peripheral survival and activation surface phenotypes, we have generated the transgenic mouse strain expressing transgenic β-chain of TCR 1D1 (belonging to the Vβ6 family) on the genetic background B10.D2(R101). Intrathymic development of T cells in these transgenic mice is not impaired. The repertoire of peripheral T lymphocytes in these mice contains 70–80% of T cells expressing transgenic β-chain and 20–30% of T cells expressing endogenous β-chains. The ratio of peripheral CD4⁺CD8^? and CD4^?CD8⁺ T lymphocytes remained unchanged in the transgenic animals, but the percent of T lymphocytes with the “naive” phenotype CD44^?CD62L⁺ was significantly increased, whereas the levels of effector memory CD44⁺CD62L^? and central memory CD44⁺CD62L⁺ T lymphocytes were markedly decreased in both subpopulations. On the contrary, T lymphocytes expressing endogenous β-chains had surface phenotype of activated T cells CD44⁺. Thus, for the first time we have shown that the pool of T lymphocytes with different activation phenotypes depends on the structure of T cell receptors.