Na,K-Atpase in renal tissue of rats in the dynamics of experimental nephritis]

The authors undertook comparative study of the Na, K-ATPase activity in the red cells, ghost corpuscles, and in the cortex and medulla of kidneys of rats with experimental glomerulonephritis (GN) induced by injection of nephrotoxic serum (NTS), during an acute course of the process (1 and 2 weeks after NTS injection) and in chronic affection of the kidneys (10 weeks after NTS injection). The activity of the enzyme both in the red cells and in the ghost corpuscles was reduced significantly, by 28 and 22%, respectively, in the acute period of the disease (one week after NTS injection) but was restored to normal values in the period of chronic affection of the kidneys. The activity of the enzyme did not change in the cortex during the whole period of the study, but in the medulla it diminished in the acute period of the disease and remained reduced (by 27% on the average) during the chronic phase. It is concluded that reduction of the enzyme activity in the studied objects was not caused by the presence of endogenous inhibitors of the enzyme. It is suggested that reduction of Na, K-ATPase activity in the renal medulla may be one of the factors of increase of Na and water excretion in the urine in the chronic phase of GN.     

Antiarrhythmic effect ofRodiola rosea and its possible mechanism

Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N ^o 8, pp. 175–176, August, 1993     

The Effects of Ante- and Postnatal Hypoxia on the Central Nervous System and Their Correction with Peptide Hormones

Ante- and postnatal hypoxia significantly worsened the postnatal development of animals. The posthypoxic behavioral model included hyperactivity and decreased learning ability, these being typical manifestations of attention deficit disorder. A peptide constellation prevented and significantly improved posthypoxic postnatal development and eliminated the majority of negative behavioral changes.     

Endocrine functions in hypertensive rats of the NISAG strain exposed to epinephrine

Endocrine functions were investigated in normotensive (Wistar) and hypertensive (NISAG) rats before and on days 3, 7, and 21 after subcutaneous epinephrine administration. Rats of the NISAG strain are characterized by elevated plasma levels of aldosterone and thyroxine and lowered plasma levels of immunoreactive insulin, and their endocrine system develops a much stronger response to a single epinephrine injection than does that of Wistar rats. This is manifested in a still higher aldosterone level, elevated corticosterone and insulin concentrations, and reduced thyroxine content in the plasma. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 495–498, May, 1996     

Analysis of psychomotor activity in children with spastic infantile cerebral palsy by using the computer-assisted test system "Rhythmotest"

The paper considers how to obtain quantitative characteristics of sensomotor responses while tracing, learning, and reproducing rhythmical stimuli of different frequency and modality which can be used to assess psychomotor activity, perception, attention, short-term memory in schoolchildren with infantile cerebral paralysis. The results of examinations of children with this condition are given and analyzed.     

Dynamics of child's cognitive development in transition to schooling

Intensive maturation of arbitrary attention occurs in the making of higher mental functions in children in transition to schooling. The study has yielded standard indices of changes in some higher mental functions at the age of 6-8 years, which makes it possible to make a timely objective diagnosis in mental and neurological practice to predict the child's development, and to provide a required complex of medical and pedagogical corrective measures.     

Computer-assisted screening of the cognitive sphere in school children

The cognitive sphere was studied in schoolchildren with good study progress by using computer test systems. This provided age-dependent standards of major cognitive functions: perception, attention, memory, psychomotor activity, and thinking that determine the quality of cognitive activity. Comparatively, this may objectify age-specific prognosis of schoolchildren and specify causes of learning difficulties in children.     

An experimental study of the chemotherapeutic efficacy of flurenizid, a new antitubercular pharmaceutical

The efficacy of a chemotherapeutic effect of flurenizid, a new antituberculous drug, was experimentally demonstrated. Flurenizid is an aromatic heterocyclic derivative. As estimated on the models of hematogenic disseminated and destructive pulmonary tuberculosis, a chemotherapeutic dose of the drug was 20 and 50 mg per kg body weight of an animal. Phagocytotic stimulation and fibrillogenetic intensification represent one of the mechanisms of its action. The most pronounced efficacy of flurenizid was noted when it was combined with isoniazid.     

Synthesis of Sorption Materials from Low Grade Titanium Raw Materials

In this paper, a universal technology is proposed for processing low-titanium mineral raw material—apatite-nepheline ore waste, including its treatment with sulfuric or hydrochloric acid in a two-stage mode with a sequential increase in the concentration. This technique allowed us to remove nepheline and apatite in the first stage and achieve a titanium mineral content of TiO₂ of more than 30%; in the second stage, we were able to convert the titanium into its precursors—titanyl sulfate monohydrate TiOSO₄·H₂O and a hybrid rutile-silica composition. The key stage in the sorbent synthesis is the reaction of the precursor with a phosphoric acid solution. The preferred sequence of operations begins with the mechanical activation of the precursor, causing morphological changes in it, and subsequent treatment with phosphoric acid at different concentrations under atmospheric conditions and in an autoclave, accompanied by phase transformations. Conditions for the chemical reactions which regulated the composition and structure of the final product and, accordingly, its sorption activity were found. With the help of XFA, the phase compositions of the sorbents were identified, including the individual crystalline phase α-TiP obtained from TS or the crystalline phase αTi(HPO₄)₂∙H₂O, which is in an amorphous silica matrix obtained from a rutile–silica composition.     

Prolonged Social Isolation and Social Instability in Adolescence in Rats: Immediate and Long-Term Physiological and Behavioral Effects

After weaning on the 21st day of life, Wistar rat pups were kept in groups of 4–5 individuals for six weeks (control group), in individual cages (social isolation group), or were subjected to alternate days of isolation and housing in groups of 10 rats with constant rotation of partners (social instability group). Some of the animals were then decapitated for investigations, while the remainder were tested and left undisturbed for two months in groups of 4–5 individuals. The animals were retested as adults. Body, thymus, and adrenal weight were measured, along with blood corticosterone levels at rest and in acute stress; basal testosterone levels, basal and stress systolic arterial blood pressure, and the amplitude and prepulse inhibition of the acoustic startle reaction were assessed, and the behavioral manifestations of anxiety and depression were evaluated. The results showed that social environment factors in adolescence affected the animals’ physiological and behavioral characteristics, some effects being transient and settling on subsequent housing in stable groups, others persisting into adulthood, and a third group becoming significant only as rats became adults.