New Gene Crt(Curly Roots) Controlling Pea (Pisum sativum L.) Root Development

Using ethyl methane sulfonate (EMS) treatment of the seeds ofline SGE, a new mutant of pea (Pisum sativum L.) with alterationsin root development was obtained. The mutant phenotype dependson the density of the growth substrate: on sand (a high densitysubstrate) the mutant forms a small compact curly root systemwhereas on vermiculite (a low density substrate) differencesbetween the root systems of the mutant and wild type plantsare less pronounced. Genetic analysis revealed that the mutantcarries a mutation in a new pea gene designedcrt (curly roots).Gene crt has been localized in pea linkage group V. The mutantline named SGEcrt showed increased sensitivity to exogenousauxin and an increased concentration of endogenous indole-3-aceticacid (IAA) in comparison with the wild type line SGE. Copyright2000 Annals of Botany Company Pisum sativum L., root development, garden pea mutant, curly roots, auxin, environmental stimulus response     

Effect of specific antibodies on active immunity development in those inoculated with an antirabies vaccine

The study of the effect of gamma globulin introduced in different doses (0.5 and 0.25 ml/mg) in combination with Fermi rabies vaccine (observations on humans were made) and with cerebral rabies vaccine inactivated by UV irradiation (in animal experiments) demonstrated that the injection of the higher doses of gamma globulin resulted in lower geometrical mean of antibody titers. Therefore, in combined administration of rabies vaccine and gamma globulin for postexposure rabies prevention it is advisable to reduce the dose of gamma globulin by one-half.     

Characteristics of the structural organization of the phylogenetically new fields in the human neocortex

The myeloarchitectonics of the specific human fields 40, 39, 37c, 37b of neocortex and also fields 17 and 19 which are the cortex end of visual analyzer has been studied with the help of neurohistological and quantitative methods. According to the character of the fibrous bundles, their diameter, the quantity of the fibrous in them and the diameter of the fibrous gradual changes from field 17 to field 19 and further to field 39 have been shown. It is an evidence of the succession between phylogenetically older and younger fields of the cortex. The peculiarities of the field quantitative myeloarchitectonics differing in the function and genesis are marked by heterochronous growth of these fields square in the process of evolution.     

Hypothermic effect on mice of a 1-10 kD fraction of the small intestine of the hibernating suslik Citellus undulatus during hypoxia and hypercapnia

Studies have been made on a possibility of inducing a prolonged hypothermia by injections to albino mice of a fraction with a molecular mass 1-10 KD isolated from the small intestine of hibernating ground squirrels. Specific conditions for the onset of hibernation (hypoxia, hypercapnia, temperature) were simulated. Exposure of mice to hypoxia and hypercapnia for 2 hours in combination with injection of the mentioned fraction extended hypothermic condition in animals up to 24-36 hours as compared to 2-3 hours after sole injection of the fraction. After the injection of 5-OT under the same conditions, the prolonged hypothermia was less stable.     

A non-enzymatic method of preparing isolated hepatocytes: assessment of their morpho-functional activity

A method for isolating hepatocytes using the two-step liver perfusion by chelate-containing solutions is described. The hepatocytes obtained are highly inactive for the trypan blue staining test, (not less than 90%), ATP content, the rate of endogenic respiration and its stimulation by succinate, a degree of xenobiotic oxidation.     

Study of trimethoprim sensitivity in strains of Yersinia pestis isolated from various natural foci of plague

The effect of exogenic addition of purines and pyrimidines on trimethoprim sensitivity was studied in 134 vaccinal and virulent strains of the plague causative agent isolated at various periods in 12 natural plague foci. 74 strains proved to be sensitive to low concentrations of trimethoprim in the cultivation media irrespective of the presence or absence of thymine or thymidine in them. In this respect the strains differed from many other bacterial species which in the presence of thymidine or thymine were resistant to high concentrations of trimethoprim. 60 natural arginine deficient strains of the plague causative agent from Transcaucasia and Mongolia showed high levels of resistance to trimethoprim on media with thymine or thymidine. The possible mechanism of the plague microbe sensitivity to trimethoprim in the presence of thymine or thymidine is discussed with an account of the literature and original data.     

Expression in Escherichia coli of DNA coding for human tumor necrosis factor

The variants of expression in Escherichia coli of artificial DNA coding for human tumor necrosis factor, an important immune modulator with selective cytotoxic action on a number of transformed cell lines have been described. The DNA was placed under control of either phage M13 promoter of gene for main coat protein or tandem of pair of E. coli tryptophane promoters. It has been shown that E. coli cells harbouring plasmids described with artificial TNF gene provide good level of protein biosynthesis. The protein has been purified by anion exchange chromatography near to homogeneity and used for preparation of monoclonals. As result three hybridomas effectively produced high affinity monoclonal anti-TNF antibodies have been obtained and characterized.     

Positive selection is a general phenomenon in the evolution of abalone sperm lysin

Lysin is a 16kDa acrosomal protein used by abalone sperm to create a hole in the egg vitelline envelope (VE). The interaction of lysin with the VE is species-selective and is one step in the multistep fertilization process that restricts heterospecific (cross-species) fertilization. For this reason, the evolution of lysin could play a role in establishing prezygotic reproductive isolation between species. Previously, we sequenced sperm lysin cDNAs from seven California abalone species and showed that positive Darwinian selection promotes their divergence. In this paper an additional 13 lysin sequences are presented representing species from Japan, Taiwan, Australia, New Zealand, South Africa, and Europe. The total of 20 sequences represents the most extensive analysis of a fertilization protein to date. The phylogenetic analysis divides the sequences into two major clades, one composed of species from the northern Pacific (California and Japan) and the other composed of species from other parts of the world. Analysis of nucleotide substitution demonstrates that positive selection is a general process in the evolution of this fertilization protein. Analysis of nucleotide and codon usage bias shows that neither parameter can account for the robust data supporting positive selection. The selection pressure responsible for the positive selection on lysin remains unknown.      

Effect of amphoterecin B on the plasma membranes of a tissue culture of puppy kidney]

The effect of amphotoericin B on the chemical composition of the plasmic membranes of the puppy kidney tissue was studied. It was shown that amphotericin B in a concentration of 10 Units/ml induced changes in the quantitative content of proteins, lipids and RNA in the chemical composition of the plasmic membranes. The effect of amphotericin B on the composition of proteins and lipids in the membranes was also studied. It was found with the method of electrophoresis in polyacrylamide gel that after exposure of the culture cells to the antibiotic significant shifts in the composition of the membrane proteins took place. According to the findings of thin-layer chromatography amphotericin B markedly changed the quantitative content of the fractions in the composition of lipids in the plasmic membranes. Significant deviations under the effect of the antibiotic were observed in the quantitative ratio of separate fatty acids contained in the lipids of the membrane preparations studied. On the basis of the results obtained it was supposed that the mode of action of amphotericin B on the cell was associated with impairement of the plasmic membrane structure by the antibiotic.