Molecular-biological approaches to studying gene expression during regeneration

This paper constitutes a review of the methodical approaches allowing analysis of the mechanisms underlying development and differentiation. Progress in investigation of the mechanisms underlying embryogenesis is related to the discovery of genic families in the Drosophila genome, which are responsible for different periods of embryogenesis. The true revolution in studies of developmental mechanisms began with the application of molecular-genetic methods for analysis of Drosophila mutant lines. The clarification and analysis of the genes controlling regeneration is one of the most effective paths toward an understanding of the mechanisms underlying regeneration. No mutations affecting regeneration are, and the development of alternative (i.e., not based on mutation analysis) methods of discovery of the genes controlling regeneration is necessary for investigation of the genetic mechanisms of regeneration. The advantages and drawbacks of the two main approaches for discovery of the genes controlling regeneration are considered. The first approach is based on the production of a bank of sequences expressed in the regenerating structures and subsequent screening of the bank by the known probes. This approach also involves analysis of the structure, function, and expression pattern of the obtained homologs. The second approach is based on subtractive hybridization, which allows identification of the genes specifically expressed in the regenerating structures. This approach was made it possible to identify, for the first time, new genes specifically expressed during lens and retina regeneration in amphibians.     

The use of immunomodulators in the surgical treatment of complicated gastric disease

While examination of 83 patients it was established that in the presence of complicated gastric and duodenal ulcer disease the secondary immune deficiency is developing, which deepens after the surgical intervention conduction. Tiotriazolin, promoting the immune system state and the blood biochemistry indexes normalization, the immune system state and the blood biochemistry indexes stimulation, hemopoiesis stimulation, the treatment results improvement, was applied for immunomodulation.     

Use of the CRITIKON Cerebral Redox for cerebral oximetry

Gaucher-like cells were found in the bone marrow and liver of an Omani teenager who had common acute lymphoblastic leukemia (cALL) confirmed on peripheral blood analysis by the presence of CD10 antigen. Leukocytic or fibroblastic beta-glucocerebrosidase enzyme activity was not measured, but other biochemical data and features of bone marrow on electron microscopy were not indicative of genuine type 1 Gaucher's disease. To our knowledge, this is the first report of pseudo-Gaucher's cells in association with cALL.     

Effect of preliminary plastic deformation on the structure and physicomechanical properties of aging invar alloy N30K10T3

The invar alloy N30K10T3 after water quenching from 1150°C (austenite, γ phase) has the temperature of the start of martensitic transformation M _s ≈ ?80°C and the Curie temperature T _C ≈ 200°C. The effect of aging-induced phase decomposition in a deformed supersaturated solid solution on its hardness HV, electrical conductivity σ, magnetic permeability μ, and linear expansion coefficient β has been studied. It has been shown that cold plastic deformation of the alloy (at 20°C) to 30–50% increases its hardness, virtually does not change the conductivity, and decreases permeability. Aging of the deformed invar results in increasing HV and σ and decreasing μ. At room temperature, the deformed invar has a low linear expansion coefficient; its magnitude grows the faster, the greater the aging temperature T _a. Plastic deformation increases the density of dislocations, which form a banded substructure in austenitic grains. Besides, a metastable martensitic phase has been observed, which undergoes a reverse martensitic transformation into austenite upon heating in the temperature range from 550°C to 650°C. This transformation causes a decrease in the linear expansion coefficient β(T) of the deformed material. In samples aged at T _a = 700°C (after deformation), an athermal aging-induced martensite (α_a phase) appears after cooling them to 20°C. The appearance of the α_a phase is due to an increase in the temperature of the start of the martensitic transformation to above the room temperature caused by aging. In the samples containing the α_a phase, there is observed a decrease in β in the temperature range from 350 to 670°C, which is due to the reverse transformation of the aging-induced martensite into austenite (α_a → γ).     

Analysis of electrical phenomena accompanying the growth of Neurospora crassa hyphae: theory and experiment

To describe electrical phenomena observed in growth of Neurospora crassa hyphae, a theoretical model was developed considering the hypha as a one-dimensional electric cable with non-uniform longitudinal distribution of current sources reflecting the activity of proton pumps. A profile of the density of the pump current along the hypha is proposed, at which the results of simulation quantitatively coincide with the results of physiological experiments. The model values of energy coupling in the growth zones were estimated. The experimental dependence of the elongation rate of regenerating apical hypha fragments on their lengths was determined. Based on the comparison of these experimental results with the results of analysis of the model, the contribution of the axial metabolite transport, from the distal parts of the hypha to the apical part, to the dynamics of the apical cell growth was estimated. The possibility of evaluating the intensity of high-molecular-weight syntheses and/or accumulation of substances in granules was demonstrated. The growth rate of the regenerating hypha fragments was shown to correlate with the electric current flowing into the apical fragment 0.2-mm in length.     

Polymorphism of pericentromere heterochromatin of polytene chromosomes of ovarian trophocytes in natural populations of the malaria mosquito Anopheles messeae Fall

The HBsAg status and demographic data of 2480 pregnant women who attended antenatal clinics at Maternal and Child Health Centres in Hong Kong were collected by means of a self-administered questionnaire over a 1-week period in July 1996, to explore the underlying reason of a higher than expected HBsAg prevalence. Local women constituted 49.2% of the sample, mainland Chinese 39.7% and others 11.1%. The overall HBsAg prevalence was 10.0%. When related to place of birth, those born in Hong Kong had a prevalence of 8.4% whereas the prevalence of those born in mainland China was 13.1% (P < 0.001). The overall HBsAg carriage rate is high because of a higher rate in immigrants in the community. It is apparent that the HBsAg prevalence of local people in Hong Kong has been decreasing in the past decade. Overall, the current HBsAg carriage rate in the local adult population is estimated to have declined to about 8%.     

An experimental study of non-Newtonian properties of water under electroexplosive loading

Non-Newtonian properties of water in the shock-wave (electroexplosive) experiment are studied. Powerlike dependences of the deformation rate depending on the stress amplitude at the wave front and the spall strength depending on the strain rate during unloading are obtained.