Antioxidant and Antiamnestic Effects of Potassium Comenate and Comenic Acid under Conditions of Normobaric Hypoxia with Hypercapnia.

Potassium comenate and comenic acid exhibit manifest and virtually identical antioxidant activity under conditions of hypoxia with hypercapnia. The effects of these drugs on conditioned reflex training with positive reinforcement differ significantly. Potassium comenate promotes retention of the learning capacity and memory in hypoxic rats at the level of intact control, that is, exhibits a pronounced protective antiamnestic effect, while comenic acid only facilitates training of the conditioned reflex with positive reinforcement.

Experimental evaluation of new chitin-chitosan graft for duraplasty.

Natural materials such as collagen and alginate have promising applications as dural graft substitutes. These materials are able to restore the dural defect and create optimal conditions for the development of connective tissue at the site of injury. A promising material for biomedical applications is chitosan-a linear polysaccharide obtained by the deacetylation of chitin. It has been found to be nontoxic, biodegradable, biofunctional and biocompatible in addition to having antimicrobial characteristics. In this study we designed new chitin-chitosan substitutes for dura mater closure and evaluated their effectiveness and safety. Chitosan films were produced from 3 % of chitosan (molar mass-200, 500 or 700 kDa, deacetylation rate 80-90%) with addition of 20% of chitin. Antimicrobial effictively and cell viability were analysed for the different molar masses of chitosan. The film containing chitosan of molar mass 200 kDa, had the best antimicrobial and biological activity and was successfully used for experimental duraplasty in an in vivo model. In conclusion the chitin-chitosan membrane designed here met the requirements for a dura matter graft exhibiting the ability to support cell growth, inhibit microbial growth and biodegradade at an appropriate rate. Therefore this is a promising material for clinical duroplasty.

Effect of Potassium Comenate on CNS Functional Status in Rodents Exposed to Combined Hypoxia and Hypercapnia in Comparison with Normally Ventilated Animals.

The effects of potassium comenate on functional state of CNS in mice and rats were studied in the open-field and hole-board tests under control conditions and after acute exposure to hypoxia-hypercapnia. The effects of potassium comenate on CNS were also studied in rodents subjected to propofol-induced sleep. Preliminary administration of 4 mg/kg potassium comenate for 3 days attenuated the posthypoxic changes in behavioral reactions (emotional anxiety/reactivity). The pronounced stress-protective effect of potassium comenate was observed both on days 1 and 14 after exposure to hypoxia-hypercapnia. Under normal conditions, potassium comenate moderated behavioral reactions and augmented somniferous effect of propofol. We hypothesized that the antihypoxic effect of potassium comenate is determined by its stress-protective and sedative potencies.

Comparative Analysis of Antioxidant Properties of Comenic Acid and Potassium Comenate in Modeled Immobilization Stress.

We studied antioxidant protective effect of comenic acid and potassium comenate in doses of 2, 4, and 8 mg/kg under conditions of oxidative stress in the brain of mice exposed to immobilization stress. Administration of potassium comenate and comenic acid in the above doses for 3 days before stress prevented the development of oxidative processes in the brain of stressed animals. The antioxidant effect of potassium comenate more pronounced.

[The morphological state of the adenohypophyseal somatotrophs during body development under conditions of protein-energy insufficiency]. / Izuchenie morfologicheskogo sostoianiia somatotropov adenogipofiza pri razvitii organizma v usloviiakh belkovo-énergeticheskoi nedostatochnosti.

The quantitative morphometric analysis of the somatotrophs of adenohypophysis of the mice developing in prenatal and early postnatal ontogenesis at the protein energetic insufficiency (PEI) was conducted at the light and electron-microscopic levels. The PEI was produced by feeding the female mice starting from the 1st day of their pregnancy with the diet containing half as many, as compared to control, nutrients (5% of protein included) at the cost of incorporating the cellulose. Adenohypophyses of 20-day old badly nourished experimental mice had a changed relationship among the types of cells: the proportion of chromatophobic cells was 39% which was significantly higher than control values (25%). The decrease in the portion of differentiated cells has occurred in the main at the expense of somatotrophs: their portion was 49% (in control--61%). The volume of cytoplasm of somatotrophs in the hypophyses of test animals is less than control value by 30%. Quantitative electron-microscopic analysis demonstrated that volumetric fractions of somatotrophs cytoplasm occupied by the endoplasmatic reticulum, Golgi complex, mitochondria, lysosomes in the malnutrition test do not significantly differ from the appropriate control values. Under protein insufficiency, a decrease of the medium diameter of the secretory granules (by 1.9 times as compared to control) and their content (by 1.7 times) in the somatotrophs has been noted. Thus in the adenohypophysis of mice developed under conditions of prenatal and early postnatal protein insufficiency there prevails the type of somatotrophs with the small volume of cytoplasm and small-sized secretory granules. This type of somatotrophs is classified with the actively functioning cells.

[The effect of injections of arginine vasotocin and mesotocin on the function of the interrenal gland in the frog Rana temporaria 2 months after the removal of the anterior lobe of the hypophysis]. / Vliianie in''ektsii arginin-vazototsina i mezototsina na sostoianie interrenalovoi zhelezy liagushki Rana temporaria spustia dva mesiatsa posle udaleniia perednei doli gipofiza.

Morphometric and biochemical studies have been made on the activity of interrenal gland in the frog Rana temporaria after removal of the anterior lobe of pituitary and injections of arginine vasotocin and mesotocin. It was demonstrated that the activity of this gland after the operation decreases increasing after arginine vasotocin injections.

[Ultrastructural characteristics of the cerebellar cortex in the postnatal development of animals with protein-calorie malnutrition and in subsequent rehabilitation]. / Osobennosti u'ltrastruktury kory mozzhechka pri postnata'lnom razvitii zhivotnykh v usloviiakh belkovo-énergeticheskoi nedosta- tochnosti i posleduiushchei reabilitatsii.

An electron microscopical investigation of the cerebellar cortex has been carried out in mice, kept during the 10th-40th days of their life at a diet with protein insufficiency and a subsequent food rehabilitation and food rehabilitation with carnitine addition to the diet on the 41st-70th days of their life. A sharp protein limitation in the diet results in the most essential changes in the neuropil, while the ultrastructure of the piriform neurons changes slightly. Amount of the synaptic vesicles in small axonal terminals decreases and their localization in the area of the synaptic contacts changes. Simultaneously, degeneratively changed axonal terminals often occur, they demonstrate a rather electron opaque axoplasma. The food rehabilitation mainly normalizes the ultrastructure of the cerebellar cortex elements, however, in the neuropil altered axonal terminals with a high electron opaque axoplasma occur. After the food rehabilitation with carnitine addition to the diet, the cerebellar cortex ultrastructure not only normalizes, but even demonstrates certain signs of hypertrophy.

[Effect of protein-calorie deficiency on the ultrastructure of synapses in the molecular layer of the cerebellar cortex in developing and adult animals]. / Vliianie belkovo-énergeticheskoi nedostatochnosti na ul'trastrukturusinapsov molekuliarnogo sloia kory mozzhechka razvivaiushchikhsia i vzroslykh zhivotnykh.

The influence of protein-caloric deficiency on the ultrastructure of synapses in the molecular layer of the cerebellum has been quantitatively assessed in young and adult mice. It has been found that protein-caloric deficiency in the early postnatal period delays the time of axo-dendritic synapse development in the neuropil. Adult mice were more resistant to the influence of protein-caloric deficiency because of an increase in compensatory-adaptive reactions found in the cerebellum.

[Ultrastructural changes in synaptic junctions of the mouse neocortex during rehabilitation after prolonged protein-calorie malnutrition]. / Ultrastrukturnye izmeneniia sinapticheskikh kontaktov neokorteksa myshei v protsesse reabilitatsii posle dlitel'noi belkovo-énergeticheskoi nedostatochnosti.

The quantitative ultrastructural study of neocortical synaptic junctions has been performed during rehabilitation after protein-caloric deficiency. It has been shown that simple food rehabilitation does not lead to absolute restoration of synaptic junctions. However, food rehabilitation with carnitine restores the ultrastructure of synaptic junctions, with the length of the active zones and the number of spine apparatus cisterns exceeding the control values. Nevertheless, synaptic cleft width and postsynaptic density remain lower than in the control group, both after simple food rehabilitation and food rehabilitation with carnitine.

[Ultrastructural characteristics of the neocortex during rehabilitation from the sequelae of long-term protein-energy deficiency]. / Osobennosti ul'trastruktury neokorteksa v usloviiakh reabilitatsii posledstvii dlitel'noi belkovo-énergeticheskoi nedostatochnosti.

Electron microscopy of mouse neocortex was carried out during rehabilitation following long-term protein-caloric deficiency. Food rehabilitation led to partial recovery of brain ultrastructure, however, a high neuronal level of secondary lysosoms and lipofuscin bodies was preserved, with the changes in the spine apparatus and synaptic contacts persisting in neuropile. Carnitine addition to food during rehabilitation increased the number of free ribosomes in cortical neurons. A substantial development of granular endoplasmic reticulum was observed. A greater number of spine apparatus cisterns was detected, however, like in conventional rehabilitation, the width of synaptic clefts and postsynaptic densities remained narrower than in control mice.

[Change in the staining properties of pyriform neurocytes in the mouse cerebellum during protein-calorie deficiency and subsequent rehabilitation]. / Izmenenie tinktorial'nykh svoistv grushevidnykh nevrotsitov mozzhechka myshei pri belkogo-énergeticheskoi nedostatochnosti i posleduiushchei reabilitatsii.

Quantitative analysis has been carried out on semithin sections of cerebellum cortex to investigate the relation between Purkinje cells with different dyeing properties. The number of dark Purkinje cells was found to increase after a month-long food rehabilitation of ill-fed mice. At the same time addition of carnitine to the mouse food has resulted in a significant decline in the number of dark Purkinje cells, as compared to control animals. The data obtained suggest that the rising number of dark Purkinje cells in the cerebellum cortex under conditions of malnutrition is probably due to the increased intracellular accumulation of free fatty acids.

[Ultrastructural changes in the neuropile of the sensorimotor cortex during long-term protein-calorie deficiency]. / Ul'trastrukturnaia kharakteristika izmenenii neiropilia sensomotornoi zony kory bol'shogo mozga pri dlitel'noi belkovo-énergeticheskoi nedostatochnosti.

The effect of alimentary (protein-caloric) deficiency on the brain sensomotor cortex of mice was studied during their postnatal development. It was found that malnutrition of mice from day 10 to day 40 of postnatal period brought about the most remarkable changes in synaptic junctions located on the dendritic spines. They manifested destruction of the spine apparatus, reduction of the width of synaptic slits and of postsynaptic membranes. Dystrophic and destructive alterations are frequently encountered in dendrites, axon terminals, and myelinized axons, indicating the reduced compensatory functions of the CNS.

[Electron microscope study of the changes in the pyriform neurocytes in the mouse cerebellum during protein-calorie deficiency]. / Elektronno-mikroskopicheskoe issledovanie izmenenii grushevidnykh nevrotsitov mozzhechka myshei, razvivaiushchikhsia v usloviiakh belkovo-énergeticheskoi nedostatochnosti.

The changes in the distribution of dark, light and intermediate pyriform neurocytes (Purkinje's cells) in the cerebellum of mice which developed under the conditions of protein-caloric deficiency were assayed from the 10th to the 40th day of mouse life. In the control animals, the number of dark cells was 7 +/- 3%, of intermediate 44 +/- 7%, and that of light ones 49 +/- 7%. Under malnutrition the number of dark cells rose to 26 +/- 5% (P less than 0.01), that of intermediate cells fell to 33 +/- 6% (P less than 0.01), and the number of light cells changed insignificantly (41 +/- 6%, P less than 0.1). Electron microscopy of the ultrastructure of dark cells has disclosed dystrophic and destructive changes in the nucleus and in the main organelles of the cytoplasm. Pronounced astroglial reaction was not infrequently observed around dark cells.

[Changes in the vectorcardiogram in rheumatism with coronary vessel lesions]. / Izmeneniia vektorkardiogrammy pri revmatizme s porazheniem venechnykh sosudov

Changes in vectorcardiograms (VCG) taken in 5 projections by the I.T. Akulinichev technique were studied in 101 patients with rheumatic fever involving the coronaries. The VCG changes were found not to be specific of rheumatic coronaritis, but to reflect the degree of coronary insufficiency and myocardial hypoxia in general. In coronaritis with myocardial infarction VCG displayed asynchronism and the QRS complex deformities, their unlocked pattern, and a decrease in the T wave amplitude. When myocardial infarction of a rheumatic genesis developed, signs of focal myocardial lesion appeared on the VCG similar to those observed in cases of ischaemic heart disease. Vectorcardiography was concluded to significantly supplement the capacity of electrocardiography in revealing coronarites.