Morphometric characteristics of the brain in children aged one year (magnetic resonance tomography data).

The aim of the present work was to identify complex morphometric characteristics of the living brain in children aged one year with assessment of individual variation (sexual, interhemisphere) by magnetic resonance tomography. The results demonstrated sexual dimorphism in brain sizes: endbrain sizes were generally larger in boys, while structures in the stem part of the brain were larger in girls. Interhemisphere asymmetry of the brain was found in one-year-old children - in most cases, lobe sizes were greater in the right hemisphere as compared with the left.

[Brain morphometric characteristics of one-year-old infants (according to magnetic resonance tomography data)].

The present study was designed to give the integrated intravital morphometric characteristic of the brain of one-year-old infants taking into account their individual variation (sex-related, interhemispheric) using magnetic resonance tomography. The research has revealed a sexual dimorphism of the brain dimensions: telencephalic dimensions were found to prevail in boys, while the dimensions of the brainstem structures were prevalent in girls. The interhemispheric asymmetry was detected in the brain of one-year-old infants; in most cases there was a prevalence of the dimensions of the right hemisphere lobes over those ones of the left hemisphere.

[Clinical course, diagnosis and treatment of cholelithic intestinal obstruction].

Forty-seven cases of intestinal obstruction due to gall-stones are analyzed. All the patients underwent surgery including enterolithotomy with two-layer intestinal closure (40), passage of stone into cecum (3), intestinal resection due to wall necrosis (3). Two patients died due to intestinal perforation with retroperitoneal phlegmon and multiple organ failure. It is concluded that clinical symptoms of cholelithic intestinal obstruction are wave-like. Intestinal X-ray and ultrasonic examinations are the most informative for final diagnosis.

[Dynamics of the pathomorphological changes in the rat brain in relation to the dose of gamma irradiation]. / Dinamika patomorfologicheskikh izmenenii v golovnom mozge krys v zavisimosti ot dozy gamma-oblucheniia.

Neurohistological, histochemical, electron-microscopic and biometric techniques were used to study the response of rat brain to irradiation within a wide range of doses. Nerve cells were shown to be highly radioresistant. At the same time, synapses and blood-brain barrier structures were highly radiosensitive. The pathomorphologic changes in different brain areas followed a dose-time function.

[The effects of space flight factors on the central nervous system. Structural-functional aspects of radio-modifying action]. / Deistvie faktorov kosmicheskogo poleta na tsentral'nuiu nervnuiu sistemu. Strukturno-funktsional'nye aspekty radiomodifitsiriushchego vliianiia.

The monograph has been dedicated to the analysis of structural and functional changes in the central nervous system of the experimental animals exposed to the isolated and combined effects of space flight factors. There have been shown many changes, which took place in the various anatomic-physiological formations of the brain, and evaluated their significance in organism's responses to the effects of ionizing and nonionizing radiation, hyperoxia, hypoxia, accelerations, vibrations and combined effects of some of those factors. The synergistic, antagonistic and cumulative (simple addition) effects of the investigated stressors along with the radiation factor on the CNS have been stated. This review is prescribed for the specialists in space biology, for physiologists, pathophysiologists, biochemists, radiobiologists and physicians.

[Structuro-functional organization of the blood-brain barrier]. / Strukturno-funktsional'naia organizatsiia gematoéntsefalicheskogo bar'era.

The analysis of the authors and published data allowed to conclude that the blood-brain barrier was a complex structural-functional system. Its basic components are endothelial cells, basal membrane, pericytes, tissue basophils, and astrocytes. The role of these structural elements in the permeability of blood-brain barrier has been studied. Organ-specific peculiarities of the brain tissue basophils have been established in rats, cats, and dogs. The astrocyte-capillary complexes were found to be very reactive, and at the same time, very plastic CNS structures.

[Early changes in the integrative systems of the brain in rats during the combined action of ethanol and gamma-irradiation]. / Rannie izmeneniia integrativnykh sistem golovnogo mozga krys pri sochetannom deistvii étanola i gamma-oblucheniia.

A study was made of Wistar male rats with the body mass of 250-270 g using neurohistological, electron microscopic and biochemical methods. The animals' heads were irradiated with gamma-quanta at a dose of 50 Gy, the rate of 6.7 cGy/s. Two minutes before or right after irradiation 15% ethanol solution (0.28 and 2.25 g/kg) was administered intraperitoneally. It was established that changes of interneuronal contacts in gamma-irradiation of the head were similar in nature to those caused by ethanol (2.25 g/kg). The effects of combined action of the above factors depended on the succession of exposure and a dose of ethanol. Slightly more noticeable synaptic changes, probably associated with mitochondrion affection and hyperhydration, were noted in ethanol administration (2.25 g/kg) after irradiation of the head.

[Status of the synapses of the end brain of rats exposed to the factors of space flight]. / Sostoianie sinapsov konechnogo mozga krys pri deistvii faktorov poleta.

Using electron microscopy, synapses of different structures of the rat end brain related to cognitive and motor acts (sensorimotor cortex, caudate nucleus) as well as memory and behavior (hippocampus) were examined. Rats were exposed to ionizing radiation, super-high frequency, hypoxia, hyperoxia, vibration and acceleration (applied separately or in combination) which have been traditionally in the focus of space and aviation medicine. Brain interneuronal junctions were found to be very sensitive to the above effects, particularly ionizing radiation and hypoxia. Conversely, synapses were shown to be highly resistant to short-term hyperoxia and electromagnetic radiation. When combined effects were used, responses of interneuronal junctions depended on the irradiation dose and order of application of radiation and other flight factors.

[Morphological analysis of the reaction of the animal brain to short-term hyperoxia]. / Morfologicheskii analiz reaktsii golovnogo mozga zhivotnykh na kratkovremennuiu giperoksiiu.

Reactions of various structures of the central nervous system of animals to short-term hyperoxia were investigated, using morphological methods available. Reactive, destructive and compensatory-adaptive changes in the structures taken under study were identified. These changes were nonspecific and similar in sign in rats and dogs. In most cases they were reversible but their polymorphism was different in phylogenetically dissimilar structures.

[Changes in synapses after gamma-irradiation of the rat head]. / Izmeneniia sinapsov pri gamma-obluchenii golovy krys.

High reactivity and, at the same time, flexibility of interneuronal contacts were observed after exposure of rat head to 2-100 Gy radiation. At high doses (200-400 Gy) radiation-induced changes played a major role in the development of the cerebral form of radiation sickness. A complete asynapsis is probably one of the causes of the animals death "under the ray" (irradiation of the head with a dose of 1000 Gy).

[Modification of radiation changes in the hemato-encephalic barrier using exogenous hypoxia]. / Modifikatsiia radiatsionnykh izmenenii gematoéntsefalicheskogo bar'era ékzogennoi gipoksiei.

The authors conducted an experimental study of a radio-modifying effect of exogenous hypoxia on the structures of the blood-brain barrier in rats early after irradiation of the head at a dose of 10 Gy. Histochemical and histological methods were used to assess the status of the endothelium, basal membrane, tissue basophils and astrocytic junction. They indicated change of these structures in irradiation and action of GGS-8 gaseous mixture. Exogenous hypoxia was shown to promote the normalization of transport through the capillary wall as a result of the prevention of injury of the structure and metabolic processes in endothelial cells and basal membrane. The astrocytic junction and, to a certain degree, tissue basophils exhibited synergy in the action of the studied factors.

[Structural and metabolic analysis of the reaction of the central nervous system to the combined action of microwave and ionizing radiations]. / Strukturno-metabolicheskii analiz reaktsii tsentral'noi nervnoi sistemy na kombinirovannoe vozdeistvie mikrovolnovogo i ioniziruiushchego izluchenii.

Structural and functional changes in the central nervous system were shown to be the same with both microwave and ionizing radiation having different mechanism of action. When the two types of radiation were delivered in a combination the sequence of delivery was of a significant importance. Antagonism of the effects was noted when microwave radiation was delivered prior to gamma-radiation. The effect was synergistic when the exposure to microwaves followed gamma-irradiation.

[Karyometric evaluation of the reactions of cerebral cortical neurons of the rat to the combined action of ionizing radiation, longitudinal G forces and vibration]. / Kariometricheskaia otsenka reaktsii neironov kory mozga krys na kombinirovannoe deistvie ioniziruiushchego izlucheniia, prodol'nykh peregruzok i vibratsii.

Using karyometric procedures, the reactions of neuronal nuclei of the middle layers of the sensorimotor cortex of rats exposed to the combined effect of ionizing radiation and longitudinal acceleration or vertical vibration were investigated. It was found that the size of neuronal nuclei varied depending on the radiation dose and the type of combinations of radiation with other exposures.

[Hematoencephalic barrier function during irradiation under hypo- and hyperoxia]. / Sostoianie gematoéntsefalicheskogo bar'era pri obluchenii v usloviiakh gipo- i giperoksii.

The hematoencephalic barrier status was shown to change depending upon radiation dose and time after exposure. Synergism, additivity, and antagonism were observed after the combined effect of radiation and a changed gas medium. On the whole, hypoxic hypoxia, as opposed to air and oxygen, had a slight radioprotective effect, but after 5 h, no variations were virtually found in the groups animals exposed to superlethal radiation doses in different gas media.

[Karyometric characteristics of the rat sensorimotor cortex in non-uniform gamma irradiation]. / Kariometricheskaia kharakteristika sensomotornoi kory krys pri neravnomernom gamma-obluchenii.

Neurocyte nuclei increase in volume without structural changes in karyoplasm at early times after gamma-irradiation of rat head with doses of 50 to 100 Gy. Irradiation of 200 Gy causes a diminution of the nuclei volume while at a dose of 400 Gy the nuclei do not change their volume. A dose as high as 1000 Gy causes severe changes in the karyoplasm leading to nucleus swelling. At later times (24-72 h), the increase in the nuclei volume is associated with the changes in the karyoplasm structure. At one and the same dose, radiation causes either a decrease (irradiation of the head) or increase (exposure of the body) in the neurocyte nuclei volume. At early times after wholebody uniform irradiation no karyometric changes are detected. The nucleus swelling is more pronounced at lower dose-rates.