Influence of a 1000 Times Weakened Magnetic Field on Embryogenesis and Ontogenesis of the Japanese Quail in Several Generations.

The paper presents experimental data on the influence of a 1000-fold weakening of the Earth's magnetic field on the embryonic and postembryonic development of the Japanese quail in three generations. It has been shown that the weakening of the earth's magnetic field by a factor of 1000 affects the formation of blood vessels in Japanese quail embryos, in particular, causing a decrease in angiogenesis in seven-day-old embryos of both the first generation (F1) and the next two ones (F2 and F3). Pathological and anatomical studies of embryos of different ages in three generations have revealed various pathologies associated with vascular system disorders, as well as disorders in the development of the beak and eyes. In the ontogenesis of F3 quails, there is a decrease in the hatchability of chicks.

Age-related adaptive responses of mitochondria of the retinal pigment epithelium to the everyday blue LED lighting.

The effect of everyday blue light (λ = 440-460 nm) on mitochondria of the retinal pigment epithelium of different age groups of Japanese quail was studied using electron microscopy, morphometric methods, and biochemical analysis. We have found a significant increase in the number of mitochondria, including those modified, mainly in young birds. In addition, cell metabolic activity increased in response to blue lighting. These changes are assumed to reflect an adaptive response of mitochondria aimed at neutralizing the phototoxic effect of blue light caused by accumulation of lipofuscin granules.

[TESTING THE PROTECTIVE PROPERTIES OF ARGON DURING SUBACUTE EXPOSURE TO HYPOXIC HYPOXIA].

Previously it has been shown that argon has a stimulating effect on biological processes including, specifically, strong protective properties during exposure to acute (1-4 hrs.) hypoxic hypoxia. Experiments with animals under hypoxia gradually growing over 3 to 7 days may give insight into mechanisms of the argon protective action. Purpose of the work was to explore character and severity of developing disorders, to attempt their prognosis and to test potentiality of argon as a protector from the effects of subacute hypoxic exposure. In two series of experiments Wistar male rats were housed in pressure chambers with different rates of O2 reduction without argon and with argon in concentration of 32-38%. Oxygen reduction from 20.9 to 9.0% in 3 days led to the death of 50% animals. Oxygen reduction to 12.0% in 7 days and one day in low-oxygen atmosphere was harmless for animals. Argon in air makes the response to hypoxia almost twice as sharp on virtually every level (red blood system, physiological, morphological and biochemical shifts) validating the concept that argon acts as a stimulator. In context of the most critical processes of adaptation to hypoxia--activation of blood formation and lipid metabolism--this sharpening of the response results in depletion of body resources and instigates irreversible shifts.

[EFFECTS OF HYPOXIA AND GROWTH FACTORS ON THE ANGIOGENIC ACTIVITY OF MULTIPOTENT MESENCHYMAL STROMAL CELLS].

The effects of fetal calf serum (FCS) growth factor concentration and cell growth phase on production of angiogenic mediators by mesenchymal stromal cells (MSCs) at different O2 levels (20 and 5%) was studied. For this purpose vascular endothelial growth factor (VEGF-A) production was measured in MSC-conditioned medium (CM); besides, branching vessels as well as vessel end points (ramification) in the chorioallantoic membrane of Japanese quail eggs (Coturnix coturnix japonica) were counted following MSC-CM application. During the standard cultivation (20% O2; 10% FCS) the total number of vessels was 1.6 times higher comparing with hypoxic condition (5% O2; 10% FCS) due to increase in ramification, the number of branching vessels did not change. Maximal (double) increase in the total vessel number was observed when CM from MSCs after hypoxia plus serum deprivation was added. VEGF-A synthesis linearly increased with FCS concentration both at 20% and 5% O2. In all cases VEGF-A level was higher at hypoxia. No direct correlation between the VEGF-A concentration and total number of vessels was noted indicating that hypoxia possibly stimulates synthesis of additional angiogenic factors to enhance vascular growth despite the drastic serum deprivation. At 20% oxygen, exponentially growing MSCs showed the highest angiogenic activity and the ramification increased in 1.6 times. Depending on O2, MSCs produced angiogenic factors required at different stages of vascularization. Specifically, mediators of ramification were accumulated in the standard conditions (20% O2) and factors stimulating growth of branching vessels--in hypoxia.

[Comparative evaluation of the effects of hypoxic gaseous mixtures varying in oxygen concentration on Japanese quail embryogenesis].

The paper presents the results of comparative characterization of the effects of low oxygen levels (10 ± 0.5 and 14.5 ± 0.5%) on developing organism. Four-day old embryos of the Japanese quail (Coturnix coturnix japonica) were chosen for the object of investigation as this is the age when avians acquire their organs and systems. Acute hypoxia (10 ± 0.5% oxygen) caused a general death of the embryos, and serious abnormalities of the eye and brain, and ectopy. Embryos that developed in the low-oxygen atmosphere (14.5 ± 0.5%) did not exhibit many of these morphological abnormalities and yet their growth was retarded apparently. Such abnormalities in acute hypoxia are ascribed to disturbance in development of extra-embryonic membranes, amnion in particular, desynchronization of morphogenetic processes and movement of embryo's tissue layers.

[Histogenesis of Japanese quail bone and cartilage tissues at the final stages of embryonic development in microgravity].

The article reports the results of comparative histological studies of skeleton development in 14- and 16-day Japanese quail embryos grown in space flight and in the 1-g gravity. The investigation revealed retardation of cartilage replacement by bone in the femur and tibia in space embryos as compared with their controls. Perichondral ossification metaphysis was reached by day 14 both in the space and control embryos. Destruction of cartilaginous diaphysis advanced onto the proximal and distal parts including the periphery. Tibia and femur cartilaginous cores in space embryos were destructed worse than in the controls in consequence of insufficient minerals supply. Perichondral ossification in the 16-day space and control embryos was alike close to completion spreading as far as the epiphysis. Long bones metaphysis was abundant in monomorphic cells as a growth bank existing during and 7 days post hatching. However, absence, in contrast to the controls, of osteogensis sites in long bones epiphysis, suggested retardation of chondrocytes calcification in these areas, as well as of ossification in space embryos.

Post-embryonic development of chicks of the Japanese quail under conditions of the limited volume.

According to our results, chicks of the Japanese quail can survive within the first 10 days of a life under conditions of the limited volume when their mobility is completely limited. However, their development was impaired in comparison with chicks housed in the common cages. Besides, the delay in development of chick's plumage has been observed. The analysis of body mass in test groups has shown that practically all chicks were smaller than chicks from control group. It is the result of feed consumption decrease (about 30% from control group) caused by the restriction of mobility of chicks. But after their transferring to the common cages at the end of the experiment, body mass in test group rapidly reached the level of body mass in control group. Research has shown that percent of alive of quail chicks maintained in the chamber of animals of complex "Incubator-2", was higher than in first two experiments. Therefore, works on improvement of devices for the maintenance of quail chicks continue, and also new adaptations develop for the maintenance of chicks in their early post-embryonic period (till 10 days) with reference to conditions of weightlessness.

[Morphological study of gastrocnemius muscle in Japanese quail chicks hatched out in space flight]. / Morfologicheskie issledovaniia ikronozhnoi myshtsy ptentsov iaponskogo perepela, vyvedennykh v usloviiakh kosmicheskogo poleta.

Slovak experiment Quail SK-6 aboard orbital station Mir in the period of February 20-27, 1999 resulted in hatching out of viable chicks of the Japanese quail. The paper presents morphologic results of investigation of m. gastrocnemius of the chicks after 4-5-d life in space microgravity. On the whole, histologically the gastrocnemius of the space chicks was very much similar to that of the control group. Muscular fibers were, which is typical, striated; bundles of myofibrills and numerous nuclei were on the periphery of the fiber under the sarcolemma. However, despite the similarity of the muscular histology, the chicks borne and exposed in microgravity displayed some deviations in the gastrocnemius as compared to their controls. Thus, Z-lines in some of the muscular fibers had a zigzag form or were doubled. In places, mitochondria were increased in size and lined up in chains longer than a sarcomere; internal membranes of the mitochondria were thickened and vacuolized, there were expanded tubules in the sarcotubular apparatus, and muscular fibers with multiple fatty vacuoles.

Main characteristics of biological components of developing life support system observed during the experiments aboard orbital complex MIR.

Since 1990, the orbital complex MIR has witnessed several incubator experiments for determination of spaceflight effects on embryogenesis of Japanese quail. First viable chicks who had completed the whole embryological cycle in MIR microgravity hatched out in 1990; it became clear that newborns would not be able to adapt to microgravity unaided. There were 8 successful incubations of chicks in the period from 1990 to 1999. In 1995-1997 the MIR-NASA space science program united Russian and US investigators. As a result, experiments Greenhouse-1 and 2 were performed with an effort to grow super dwarf wheat from seed to seed, and experiment Greenhouse-3 aimed at receiving two successive generations of Brassica rapa. But results of these experiments could not be used for definitive conclusions concerning effects of spaceflight on plant ontogenesis and, therefore, experiments Greenhouse-4 and 5 were staged within the framework of the Russian national space program. The experiments finally yielded wheat seeds. Some of the seeds was left on the space station and, being planted, gave viable seedlings which, in their turn, produced the second crop of space seeds.

Functional development of small intestine of Japanese quail hatched on MIR orbital station.

The effect of microgravity on functional development of the small intestine of Japanese quails incubated for 2-3 d and hatched on the orbital station MIR was examined. After 5 d of space flight duodenal and jejunal alkaline phosphatase (AP) activity of the experimental group was compared with the AP activity in quails of the same age hatched on the Earth (laboratory controls). Short-term microgravity leading to decreased food intake resulted in significant increase of AP activity in both duodenal and jejunal enterocytes (P<0.001) of the experimental quails. The results suggest that increased AP activity probably reflects the delayed functional development of the small intestine as a consequence of inappropriate food intake during non-physiological conditions of space flight.