Individual features of play behavior in thick-toed geckos in weightlessness and normal gravity conditions.

The object play behavior in thick-toed geckos (Chondrodactylus turneri GRAY 1864) was studied during a 30-day orbital experiment onboard the Bion-M1 biosatellite. The play object for five geckos was a marking collar that one of the geckos in the flight group removed immediately before the launch. The play behavior started when either the gecko observed the approaching floating collar or when the gecko independently approached the stationary collar, followed by manipulation of the collar and subsequent observation of its moving away. While playing with the collar, the individuality of geckos' behavior was manifested in the frequency and number of play episodes, the nature of manipulations, and the duration of interest in play during the flight. We found that thick-toed geckos could play not only with an unknown object (marking collar) but also with familiar molting skins. In weightlessness, the play behavior of geckos with molting skin fragments was similar to the play behavior with the collar and also varied between individuals. It was established that geckos maintained a similar individual level of play activity with different objects (collar and molting skins). It was found that geckos also played with fragments of molting skin under normal gravity conditions. In contrast to weightlessness, play behavior at normal gravity was rare and limited to short durations of object manipulation.

Attachment of Turner's thick-toed geckos (Chondrodactylus turneri GRAY 1864) during weightlessness and their responses to flotation.

We investigated the behavior of 15 female Turner's thick-toed geckos (Chondrodactylus turneri GRAY 1864) during a 30-day orbital experiment on the unmanned spacecraft "BION-M" No. 1. During weightlessness, the geckos maintained their ability to attach to the surfaces using the subdigital pads on their toes. On average, the geckos spent 99.9% of the time adhering to surfaces during the flight and only 0.1% floating freely. The active geckos, when starting to float, immediately restored attachment by a number of behavioral responses. The floating quiescent geckos, when resuming their active condition, responded in the same manner. The responses during flotation are similar to the behavioral reflexes triggered by a fall under normal gravity; i.e.: 1) the ventral extension of the limbs, 2) a skydiving posture, and 3) postural righting reflexes. Ventral extension of limbs was described for the first time in weightlessness. Individual variability in the frequency of flotations was found for both active and quiescent geckos during the flight. The findings show that the ability to attach to surfaces is an important factor in the geckos' adaptation to weightlessness. The behavioral responses that originated during freefall in conditions on Earth (one-G) appear as adaptations to weightlessness and remain partially effective.

[Supporting life of Pachydactylus turneri in a projected experiment aboard robotic spacecraft: choosing feed].

An experiment was carried out to validate and select feed to be supplied to Pachydactylus turneri in a 30-day orbital flight of robotic spacecraft BION-M1. Larvae of two Tenebrionidae species, i.e., Tenebrio molitor and Zophobas were tested for survivability, tolerance of hunger and cold, ability to stick to and move along different surfaces. Tenebrio molitor was shown to be best suited. A special feeder that will sustain the beetle over 30 days was designed. The experiment provided new data about Tenebrionidae biology and suggested the feeding technology for a 2-month space experiment with Pachydactylus turneri.

Comparative analysis of the skeletal changes in tetrapods after brief influence of microgravity.

Experiments involving lower tetrapods demonstrate that the degree of skeletal demineralization in spaceflights is related to the type of environmental behaviour of the animal. Probably the sensing of support reaction decreases the negative effect of spaceflight upon the bone tissue.

[The morphogenesis and spatial organization of human pineal gland concretions in Alzheimer's disease, schizophrenia, and alcoholism].

X-ray microtomography using a wavelength of 0.7 A was used to detect elevated calcium concentration areas that integrate all types of human epiphyseal concretions. They consisted of both concretions and extracellular calcium, which could not be attributed to any particular tissue. There were no concretions outside of these zones. The center of concretion formation was found to be a single source that may be an individual pinealocyte. Comparison of postmortem human epiphyses in normalcy (natural aging), in chronic alcoholism, Alzheimer's disease, and schizophrenia revealed that there were differences in both the number of concretions and their formation topology. In normalcy, the field of elevated calcium concentration was continuous whereas in patients with the study mental diseases, it was divided into separate areas. There is evidence that in mental diseases, the amount of acervulus and its density decrease, which may a marker of the development of these diseases.

[Human epiphyseal concrements in schizophrenia]. / Konkrementy épifiza cheloveka pri shizofrenii.

The epiphysis is a gland containing firm extracellular bodies (brain sand) the number of which increases with age. Microscopy and roentgen microtomography showed that in some cases of schizophrenia the amount of brain sand decreases. In parallel, cytoplasm of pinealocytes appears to contain concrements of a new type--irregular hollow spheres of 0.1-1.5 microm in size. They may contain fluoride. Typical hydroxyapatite retaining organic stroma may dissolve starting from the center both in health and schizophrenia.

[Human and animal vomeronasal systems in health and disease]. / Vomeronazal'naia sistema zhivotnykh i cheloveka v norme i patologii.

The vomeronasal organ (VO) or the second olfactory organ has the form of paired epithelial pockets at the base of the nasal septum. In animals it has various functions including reception of pheromones mediating sexual, parental and social behavior. Human VO was considered to be rudimental until the last decade of the XXth century. Since then it was found to be present almost in every adult individual and was proved to be functional. The paper provides new facts on the occurrence of VO in man and animals, analyzes possible consequences of plastic surgery of the nose and considers some vomeronasal abnormalities, their diagnosis and treatment.

Morphogenesis of asymmetry of rat brain nuclei under normal conditions and during exposure to microgravitation.

Histological and morphometrical analysis of the brain and peripheral analyzers revealed proliferative migration abnormalities of brain development and neuron differentiation in mammals during a space flight, which can limit space exploration.

[The development of the organum vomeronasale system in human embryos 19--40 mm in crown-rump length]. / Razvitie sistemy vomeronazal'nogo organa u émbrionov cheloveka 19--40 mm temia-kopchikovoi dliny.

Age-related changes in the organon vomeronasalis (VO) and related structures have been described in normal human embryos of 19, 25, 28 and 40 mm in crown-rump length and in the embryo of 19 mm in crown-rump length during abnormal development in the uterine tube. The fourth branch of the VO nerve appeared in the 25 mm embryo. Signs of asymmetry and degenerative VO changes were analyzed in the 25 and 40 mm embryos. A supposed vomeronasal ganglion has been described. The possibility of fetuses at the late stages of prenatal development using the VO system is discussed.

[Early embryonic formation of the human vomeronasal organ]. / Rannee émbrional'noe formoobrazovanie sistemy vomeronazal'nogo organa cheloveka.

We studied the origin and development of the vomeronasal system in early human embryos of 10-18 mm crown-rump length under normal and pathological conditions. The formation of the vomeronasal organ from the vomeronasal groove and placode in a 10-mm embryo is described. We propose that the vomeronasal cavity originates in the schizocoel way. We studied the development of the vomeronasal and olfactory nerves. Attention is paid to the development of the nasolacrimal duct and the epithelial plug. The possible use of the vomeronasal system by embryos during the first seven weeks of development is discussed.