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.

Immunohistochemical Analysis and Electron Microscopy of Glial Cells in the Pancreas of Fetuses and Children.

Schwann cells forming peri-insular glial sheath of the pancreatic islets in some mammals can be involved in the pathogenesis of diabetes mellitus. Human pancreatic cells contain small elongated or oval cells of unknown origin with S100-immunopositive processes. We found that cells with processes located in pancreatic islets of human fetuses and children are similar to Schwann cells by their morphological and ultrastructural characteristics, immunopositive reaction for S100, and integration with nerve endings. In the pancreas of fetuses and children, Schwann cells are often seen in forming pancreatic islets and around the pancreatic ducts. The data suggests that Schwann cells can participate in the morphogenesis of human pancreatic islets.

[Development of the Human Olfactory Bulbs in the Prenatal Ontogenesis: an Immunochistochemical Study with Markers of Presynaptic Terminals (anti-SNAP-25, -Synapsin-I, -Synaptophysin)].

We provide the data of the olfactory bulbs (OB) development in the human fetuses on the stages from 8 week to birth. Immunochistochemical markers of presynaptic terminals (anti-SNAP-25, -synapsin-I, -synaptophysin) were used to evaluate the maturation of the OB. Differentiation of the OB layers begins from periphery, which implicitly evidences that growth of the olfactory nerves fibers induses not only anatomical differentiation of the OB, but also differentiation of its functional layers. The sites of the developing glomerulus are revealed using the immunochistochemical prosedure on the stage before distinct glomerulus can be identified with common histological procedure. OB conductive system demonstrates immunoreactivity with the antibodies to the presynaptic proteins on the all stages from 10-11 weeks of fetus development. Four stages of the OB development are described. All functional layers of the OB are mature at the 22-weeks stage. Further differentiation of the OB neuroblasts, including lamina formation of the internal granular leyer, glomerular layer development, OB growth continue after 20-22 weeks stage until 38-40 weeks of the fetus develoment. Patterns of the immunoreactivity with antibodies to SNAP-25, synapsin-I and synaptophysin are completely appropriate to those of adult's OB on the 38-40 weeks of the prenatal development. Complete maturity of the human OB is achived at 38-40 weeks of the prenatal development.

Distribution of chromogranin A in human fetal pancreas.

Immunohistochemical study of distribution of chromogranin A (neuroendocrine cell marker) in the developing human pancreas was carried out. Immunopositive reaction to chromogranin A was detected in the primordial pancreas from the early period of development (8 weeks). The count of chromogranin A-positive cells in early fetuses significantly surpassed that of insulin- and glucagon-containing cells. Chromogranin A immunoreactive cells, but not cells reacting with antibodies to insulin and glucagon were detected in the pancreatic islets and pancreatic ducts during all periods of gestation. These results suggested that hormone synthesis by pancreatic endocrine cells was preceded by the expression of chromogranin A and hence, this marker could be used for studies of the mechanisms of development of the endocrine part of the pancreas.

[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.

[Immunohistochemical study of human fetal vomerona structures the nasal septum, by applying neuron-specific beta3-tubulin antibodies].

The functioning of Jacobson's or vomeronasal organ (VNO) in man is the subject-matter of discussion today. It is generally taken that VNO as an anatomic structure also remains in the adult; however, its receptor apparatus still degenerates in the fetal stage of ontogenesis. Nevertheless, the data available in the literature on the time and specific features of degenerative changes in the human fetal VNO are conflicting and ambiguous. The authors examined the human fetal nasal septum from the 8th week of development to birth, by applying the traditional histological procedures and neuron-specific beta3-tubulin antibodies. An immunohistochemical study could first show the receptor apparatus of the human fetal VNO at weeks 8-26 of development. The immunohistochemical study on a series of sections could reveal the regularities of spatial receptor distribution depending on the time of fetal development. In addition, the developed human fetal vomeronasal nerve and ganglion at weeks 8-26 were described, in human fetuses at weeks 8-26. The neuron-specific marker test has shown the nerve fibers departing directly from the VNO wall, which is inconsistent with the data available in the literature on vomeronasal nerve degeneration in this sign just after the 18th week of development.

Immunoreactivity of neuron-specific enolase (NSE) in human pancreas in health and type 1 diabetes mellitus.

The role of neuron-specific enolase (glycolytic enzyme; marker of nerve fibers and Langerhans islet in human pancreas) in the development of type 1 diabetes mellitus was studied in autopsy specimens from 6 adult patients. Autopsied specimens of the pancreas from 7 subjects without carbohydrate metabolism disorders served as the control. Autopsied specimens of the pancreas from a child with the clinical diagnosis of type 1 diabetes mellitus, a child without carbohydrate metabolism disorders, and from 7 human fetuses of 15-40 weeks gestation were also studied. In control specimens, the neuron-specific enolase was detected in the pancreatic nerve fibers and Langerhans islets. Studies of pancreatic tissue specimens from adult patients with type 1 diabetes mellitus showed no immunopositive reaction to neuron-specific enolase in insulin-negative specimens. A possible mechanism of type 1 diabetes mellitus development is suggested.

[Diabetic fetopathy in gravida with autoimmune hemolytic anemia complicated by steroid diabetes].

The authors made a clinicoanatomic analysis of fetal death in a 32-year-old diabetic gravida at 34-35 weeks gestational age. Fetal autopsy identified the characteristic signs of fetopathy: macrosomy, cardiomegaly, hepatomegaly, and brain weight reduction. Histological analysis revealed minute foci of leukomalacia with glial proliferation in the cerebral hemispheres; adipose and hyaline drop degeneration of cardiomyocytes in the heart, that of hepatocytes in the liver, the proximal renal tubular epithelial cells; hemorrhages in the respiratory portions of the lung. The pancreas displayed inflammation foci, hypertrophy and hyperplasia of the islets of Langerhans. Immunohistochemical studies identified cells with enlarged nuclei among the beta and alpha-cells. The placenta showed a large mass with pronounced changes. It has been demonstrated that steroid diabetes may lead to the development of diabetic fetopathy and placental changes, which are typical of maternal diabetes.

Development of the olfactory bulbs in human fetuses (an immunohistochemical study).

An immunohistochemical study of the olfactory bulb (OB) in human fetuses was performed. Immunohistochemical markers for nervous system-specific protein complexes S-100 and SNAP-25 were used. At 20-22 weeks of development, the development of cells expressing protein S-100 was greater in the OB than in the neocortex (the areas of the gyrus rectus and the gyrus orbitalis longitudinalis internus). These quantitative differences indicate heterochronicity in glial differentiation in the OB and cerebral cortex. Immunopositive reactions for SNAP-25 were for the first time detected at the periphery of the OB and in glomeruli in human fetuses at 15-16 and 20-22 weeks of development. Immunohistochemical staining of the OB with antibodies to SNAP-25 indicated that the human olfactory system cannot function prior to 20-22 weeks of development. In the OB of fetuses at 28-29 weeks of development, the intensity of the immunohistochemical reaction showed topological differences. The reaction with antibodies to SNAP-25 in the OB of full-term fetuses was similar to the reaction in the OB of adult humans. The results of these immunohistochemical studies using the reaction for the protein complex SNAP-25 in fetuses of different ages suggest the that the primary olfactory center in humans starts to function no earlier than the 30th week of development.

[Neuroendocrine complexes in the pancreas of nutria (Myocastor coypus) (an immunohistochemical study)].

With the application of a double immunohistochemical labeling method, several types of neuroendocrine interactions were demonstrated in the pancreas of nutria. Two types of neuroinsular complexes were detected that have the organization typical to the mammals. It was found to be typical of nutria that several pancreatic islets were integrated with nerve cells and nerve fibers. The complexes detected that reflect the interactions between nervous elements and single endocrine cells or their small groups, are species-specific. The data obtained demonstrate the diversity of neuroendocrine interactions in the pancreas and possible influence of the nervous system on B-cell differentiation.

[Neurogenic mechanisms of development of type 1 diabetes mellitus].

Immunohistochemical (tests for insulin, glucagons, periferin, SNAP-25, GFAP, NGF-R, RMR-22, MBP) and morphological studies were performed to examine the pancreatic nervous apparatus of human adults and fetuses in late phases of development. A role of the morphogenetic activity of the pancreatic nervous apparatus was investigated in type 1 diabetes mellitus (DM-1). The neurons and gliocytes located in the pancreas are suggested to have a morphogenetic activity and form a glial capsule throughout their life. The insular endocrine cells are shown to synthesize the proteins (SNAP-25, GFAP) characteristic of nerve cells and their synaptic terminals. A neurobiological model of DM-1 'development has been stated. The onset of the disease is characterized by the development of autoimmune processes directed to the nervous system. In nerve tissue protein autoimmunization, the fine insular neuroglial membrane is rapidly disrupted. This leads to the transfer of autoimmune aggression to the insulin-producing cells of the islets of Langerhans, which carry specific nerve tissue proteins onto their surface. Recovery of the islets becomes impossible without forming a protective neuroglial membrane, which makes the development of DM-1 irreversible.

Immunohistochemical detection of SNAP-25, NCAM, and insulin in the pancreas of nutria (Myocastor coypus).

Immunohistochemical study revealed three types of neuroendocrine contacts in nutria pancreas. In most cases, the pancreatic islets and individual endocrine cells were associated with a diffuse neural network. Integration of neural ganglia with the islets and innervation of endocrine cells by projections of ganglionic cells were detected. It is hypothesized that the structure of neuroendocrine interactions plays different roles in the regulation of endocrine secretion.

[The notochord proteins of true sturgeons carrying the At1 epitope]. / Belki khordy osetrovykh ryb, nesushchie épitop At1.

Previously we reported the production of monoclonal antibodies against chordin, an acidic glycoprotein from true sturgeon notochord, carrying glycans terminating with 3-sulfoglucuronic acid. In addition, monoclonal antibodies At1, not reacting with chordin, were produced. Here we describe At1 epitope expression in sturgeon tissues and target proteins for At1 antibodies, and test interaction of these proteins with chordin and other molecules carrying glycan with 3-sulfoglucuronic acid. The expression of the antigens carrying At1 epitope during sturgeon development has also been studied.

Identification of monoclonal antibody At5 as a new member of HNK-1 antibody family: the reactivity with myelin-associated glycoprotein and with two brain-specific proteoglycans, phosphacan and neurocan.

Monoclonal antibody At5 was primarily developed against chordin, a notochord-specific antigen of Acipenseridae (sturgeon fishes). In higher vertebrates the antibody reacted mainly with neural tissue antigens. In this study we have shown that the specificity of monoclonal antibody At5 is similar to that of antibodies of HNK-1 family which react with two glycolipids and with several high molecular weight glycoconjugates of neural tissue. We have demonstrated by protein sequencing and immunoblotting that one of At5 target antigens of human brain is dMAG, a derivative of myelin-associated glycoprotein. In the preparations of At5 antigens proteoglycans phosphacan and neurocan were identified by immunoblotting with specific monoclonal antibodies 6B4 and 1G2, respectively. The distribution of At5 and 6B4 immunoreactivity was studied on sections of mixed oligoastrocytoma. Oligodendroglioma area of this tumor was intensely stained with both antibodies, whereas astrocytoma area did not exhibit any At5 or 6B4 immunoreactivity.

[The determination of the cytodifferentiation of the adenohypophysis in embryonic development]. / Determinatsiia tsitodifferentsirovki adenogipofiza v zarodyshevom razvitii.

This is a review of the literature and author's own data on determination of various cell types of adenohypophysis during embryonic development. Recent studies using techniques of organ culture and immunohistochemistry have established the time of determination of glandular cells of adenohypophysis. It has been shown in rat embryos that the direction of differentiation of all major cell types of adenohypophysis is programmed late during the development of the epithelial anlage of this organ. Similar data as concerns somatotropic and prolactin cells have been obtained on chick embryos. Chick embryos possess regional type of determination of prolactin and somatotropin-containing cells in the anlage in correspondence with their location in definitive adenohypophysis.

[The differentiation of prolactin cells in an organ culture of chick embryo adenohypophysis]. / Differentsirovka prolaktinovykh kletok v organnoi kul'ture adenogipofiza kurinykh zarodyshei.

We have studied differentiation of prolactin cells in explants of cephalic and caudal parts of Rathke's pouch of 4.5 day and 5.5 day old chick embryos after their incubation in vitro lasting for 7-8 days. Indirect immunofluorescence using an antiserum against bovine prolactin was used to detect prolactin cells in the cultures. Differentiation of prolactin cells was detected regularly in explants of the cephalic lobe of the adenohypophysis anlage in 5.5 day old embryos; under certain growth conditions prolactin cells were found in explants of the same lobe in 4.5 day old embryos. Prolactin cells were either absent or found in small numbers in cultures of the caudal part of adenohypophysis of 5.5 day old embryos. Our results provide evidence for the appearance of the committed precursors of prolactin cells in the Rathke's pouch at late stages of its formation and for their regional localization in the cephalic part of the anlage. This localization is in correspondence with the distribution of differentiated cells of this type in definitive adenohypophysis.

[Somatotropic cell differentiation in an organ culture of the chick embryo adenohypophysis]. / Differentsirovka somatotropnykh kletok v organnoi kul'ture adenogipofiza kurinykh zarodyshei.

Morphogenetic potencies of the adenohypophysis tissue from 4.5 to 11-day old chicken embryos used for the differentiation of somatotropic cells were investigated by methods of organ tissue culture. STG-cells were detected in cultures by immunofluorescence using an antiserum to human STG. In vitro studies of organ cultures revealed differentiation of STG-cells when adenohypophysis tissue was cultured from the 5.5th, 7th, 9th and 11th day of development in the absence of the diencephalon. Differentiation of STG-cells occurred predominantly in embryo caudal lobe transplants after chorion-allantois culturing of Rathke's pocket fragments from 4.5-, 5.0- and 5.5-day old embryos. The data obtained suggest that at late stages of Rathke's pocket development differentiation of STG-cells is preprogrammed and that determined precursors of these cells are located in the caudal lobe of the germ.

[The use of rafts made of polymers with hydrophobic properties in organ culture--a new modification of Chen's raft method]. / Primenenie plotov iz polimerov s gidrofobnymi svoistvami v organnoi kul'ture--novaia modifikatsiia metoda plotov Chena.

A new modification of tissue culture technique implying the use of rafts of hydrophobic polymers is suggested. Polyethylene rafts appeared to be the most appropriate for tissue culture of chick pituitary. The rafts were prepared as disks with an opening in the center. Millipore filter carrying the explants was placed over the opening. The rafts had good buoyancy, remained on the surface of the culture media for 1-2 weeks and were reusable.