Metabolic features of cosmonauts after ballistic descent from the Earth orbit

The features of metabolic reactions in five cosmonauts after long-term flights on the International Space Station (ISS) and landing along a ballistic trajectory and in the cosmonauts returning to Earth in the mode of automatic controlled descent were studied. Venous blood samples were collected, and 50 biochemical parameter values that reflect the functional state of organs and tissues and characterize the main metabolic pathways were determined. On the first day of the recovery period after ballistic descent, the activity of the myocardial, liver, and gastrointestinal enzymes in the blood serum of cosmonauts was increased 1.3- to 2.1-fold; a number of the parameter values exceeded the upper normal limit. The level of C-reactive protein increased fivefold as compared with the preflight values. Marked signs of glycolysis, glycogenolysis and lipolysis activation as well as disorders of acid–base balance were observed. Changes in the biochemical parameter values in cosmonauts after landing along a ballistic trajectory differed significantly from those revealed in the same cosmonauts after long-term missions followed by automatic controlled descent to Earth. Negative metabolic changes tendency after landing along a ballistic trajectory remained for at least 14 days of the recovery period. It was concluded that changes in the metabolic reactions of cosmonauts after long-term missions to the ISS depend on the flights final stage conditions. After landing on Soyuz spaceships in the ballistic descent mode, the cosmonauts had adverse prognosis changes in the biochemical values characterizing the state of the cardiovascular system and marked shifts in the activity of the liver and gastrointestinal constellation enzymes. The dynamics of carbohydrate, lipid, and protein metabolism as well as acid–base balance indicates a significant tension of all body systems and exhaustion of its functional reserves.     

Chromosome preparations in the field from mammals long after death

Chromosome preparations of high quality can be obtained from bone marrow cells of small mammals that have been dead for 20 hr or longer. The bone marrow is rinsed out of the femurs with RPMI medium supplemented with 15% fetal calf serum. Add 0.05-0.1 ml of a 0.01% colchicine solution to 5 ml of medium-cell suspension. After 1/2-1 hr of colchicine treatment at 37 C the cells are spun down and the supernatant replaced by 5 ml of hypotonic (0.075 M) KCl. After 12 min in the hypotonic solution at 37 C the cells are fixed in methanol:acetic acid 3:1. Air dried preparations are made after repeating the fixation procedure three times and the chromosomes are stained with Giemsa, if required after pretreatment of the preparations for banding, e.g., GTG. Technical hints for field work are given. The technique has proven successful with several species of rodents and shrews.     

Experimental validation of small mammal gut microbiota sampling from faeces and from the caecum after death

Data on the gut microbiota (GM) of wild animals are key to studies on evolutionary biology (host–GM interactions under natural selection), ecology and conservation biology (GM as a fitness component closely connected to the environment). Wildlife GM sampling often requires non-invasive techniques or sampling from dead animals. In a controlled experiment profiling microbial 16S rRNA in 52 house mice (Mus musculus) from eight families and four genetic backgrounds, we studied the effects of live- and snap-trapping on small mammal GM and evaluated the suitability of microbiota from non-fresh faeces as a proxy for caecal GM. We compared CM from individuals sampled 16–18 h after death with those in live traps and caged controls, and caecal and faecal GM collected from mice in live-traps. Sampling delay did not affect GM composition, validating data from fresh cadavers or snap-trapped animals. Animals trapped overnight displayed a slight but significant difference in GM composition to the caged controls, though the change only had negligible effect on GM diversity, composition and inter-individual divergence. Hence, the trapping process appears not to bias GM profiling. Despite their significant difference, caecal and faecal microbiota were correlated in composition and, to a lesser extent, diversity. Both showed congruent patterns of inter-individual divergence following the natural structure of the dataset. Thus, the faecal microbiome represents a good non-invasive proxy of the caecal microbiome, making it suitable for detecting biologically relevant patterns. However, care should be taken when analysing mixed datasets containing both faecal and caecal samples.Subject terms: Evolutionary genetics, Evolutionary ecology, Metagenomics     

Depletion of the spermatogonia from the seminiferous epithelium of the rhesus monkey after X irradiation

In unirradiated testes large differences were found in the total number of spermatogonia among different monkeys, but the number of spermatogonia in the right and the left testes of the same monkey appeared to be rather similar. During the first 11 days after irradiation with 0.5 to 4.0 Gy of X rays the number of Apale spermatogonia (Ap) decreased to about 13% of the control level, while the number of Adark spermatogonia (Ad) did not change significantly. A significant decrease in the number of Ad spermatogonia was seen at Day 14 together with a significant increase in the number of Ap spermatogonia. It was concluded that the resting Ad spermatogonia are activated into proliferating Ap spermatogonia. After Day 16 the number of both Ap and Ad spermatogonia decreased to low levels. Apparently the new Ap spermatogonia were formed by lethally irradiated Ad spermatogonia and degenerated while attempting to divide. The activation of the Ad spermatogonia was found to take place throughout the cycle of the seminiferous epithelium. Serum FSH, LH, and testosterone levels were measured before and after irradiation. Serum FSH levels already had increased during the first week after irradiation to 160% of the control level. Serum LH levels increased between 18 and 25 days after irradiation. Serum testosterone levels did not change at all. The results found in the rhesus monkey are in line with those found in humans, but due to the presence of Ad spermatogonia they differ from those obtained in non-primates.     

Release of norepinephrine from the cat ovary: changes after ovulation.

The distribution of intraneuronal constituents involved in norepinephrine (NE) storage, uptake, and release were used to estimate changes in NE secretion from the cat ovary after ovulation induced with eCG plus hCG. The content of NE and ATP, which are principally stored in small noradrenergic vesicles (isolated at a density of 1.041 g/ml in Percoll gradient), decreased after ovulation. However, the activity of dopamine beta-hydroxylase, which is principally associated with large noradrenergic vesicles (isolated at a density of 1.033 g/ml in Percoll gradient), was only slightly decreased. Mg(2+)-dependent ATPase, located in both large and small storage vesicles, decreased only in the small storage vesicles, suggesting that preferential secretion from small noradrenergic vesicles occurred. The hormonal treatment also affected the functional capacity of the vesicles, as evidenced by the decrease in uptake and storage capacity as well as the decrease in the stimulated release of 3H-NE observed after ovulation. The aforementioned changes are characteristically seen after a sympathetic discharge; thus they strongly support the notion that ovarian sympathetic activity increases during the ovulatory process, resulting in the postovulatory decrease in both the size and functional capacity of the intraneuronal compartment where NE is stored.     

Recovery of germinating fungal conidia from the nasal cavity after environmental exposure

Background The expression of fungal allergens is increased by the germination of conidia. We assessed the state of germination of fungal conidia recovered by nasal lavage after environmental exposure. Methods Nasal lavage was performed on twenty adults at three stages: the start of the experiment, after 1 h indoors, and after 1 h outdoors. One half of the lavage liquid was immediately treated to prevent in-vitro germination and stained with periodic acid Schiff (PAS) to enable identification of germinated and ungerminated conidia. The untreated half of the lavage liquid was cultured on nutrient agar plates to enumerate and identify viable fungi. Results PAS staining showed that both ungerminated and germinated conidia, and hyphal fragments, were present in the nasal cavity. The most prevalent fungi recovered were Aspergillus, Alternaria, Cladosporium, Epicoccum, Penicillium, and Yeast species. The number of viable fungi recovered after 1 h indoors was significantly less than after 1 h outdoors (P < 0.01). Conclusions Viable fungi and germinating conidia, in addition to ungerminated conidia and hyphal fragments, were present in the nasal cavity after both indoor and outdoor exposure. This provides novel insight into the pathogenicity of exposure to fungal aeroallergens.     

Isolation of mumps virus from the inner ear after sudden deafness.

A 26-year-old woman with bilateral otosclerosis underwent right stapedectomy with an excellent result. One year later, however, she developed symptoms of mumps and within two days was completely deaf in the right ear. Prompt surgical exploration excluded a complication of the otosclerosis and a perilymph fistula, but culture of a sample of perilymph grew mumps virus. The case provides direct evidence of a relation between mumps virus infection and inner-ear damage.     

Assessment of human sperm function after recovery from the female reproductive tract

The physiology and fertile life of human spermatozoa in the female reproductive tract have received little previous attention. A technique was developed for recovering spermatozoa from human cervical mucus at various intervals after artificial insemination. The functions of these cells as measured by penetration of the human zona pellucida and fusion with the zona-free hamster oocytes were examined. Penetration into the zona pellucida was consistently observed when sperm were recovered from 1 to 80 h after insemination. Penetration through the zona into the perivitelline space (PVS) was seen from 1 to 72 h after insemination. Fusion of human sperm with zona-free hamster oocytes was observed from 1 to 48 h after insemination. Motile sperm were recovered 112 and 120 h after insemination with swimming speeds comparable to freshly capacitated spermatozoa. Concentrations of recovered sperm at these longer intervals from insemination were insufficient for sperm-oocyte assays. These studies demonstrate that human spermatozoa aged in vivo may be recovered from cervical mucus for physiologic study, and suggest that the fertile life of human sperm may be 80 h or more.