Transposition of the pacemaker in the right atrium during stimulation of the vagus nerve in the dog

The heart rate and intraatrial latencies between epicardial electrograms from three sites of the right atrium have been studied during vagal stimulation in open-chest dogs. It has been shown that alterations of latencies started at a certain cardiac cycle length irrespective of pacing frequency. A transitional process of changes from a steady latency value in the control to another steady value during vagal stimulation has been observed. The transitional process has been simulated in experimental procedure in which two sites of the right atrium were paced at close and constant frequencies. To interpret the results obtained one-dimensional model of the sinus node has been constructed. According to the model, pacemaker shift within the sinus node results from a competition between two foci of automaticity with close intrinsic frequencies.     

Determination of the number of tissue compatibility genes in the carp using the transplantation test in the third generation of induced gynogenesis

Transplantations have been carried out of anal fin in carp individual progeny of the third consecutive generation of induced gynogenesis. The part of grafts accepted made 19.4 +/- 5.0% (71 transplantations have been carried out). With the data obtained, an approximate quantity of histocompatible genes has been determined in carp which amounted to 32. Calculation has been done on the basis of the assumption that the part of histocompatible genes being in homozygous state in the given progeny equals the inbreeding coefficient of this progeny. Inbreeding coefficients have been calculated using experimental data of other authors.     

The spatial variability of the intensity of the bioluminescence field in coastal waters of the Crimean Peninsula in the spring period

The spatial variability of the vertical structure of bioluminescence intensity has been studied along the Crimean coast in the spring period. The location of a layer with a high intensity of bioluminescence has been determined and its dependence on hydrological characteristics and thermohaline structure of waters is shown. Structurization of the spatial variability of bioluminescence intensity has been made. Four regions that are distinguished by the pattern of the vertical distribution of the bioluminescence intensity have been distinguished in coastal waters of the Crimean Peninsula.     

Micrococci in the skin microbiocenosis of the breasts. Ecologic characteristics of the colony

The ecological characteristics of the micrococcal community on the skin of the mammary glands of nulligravidae, pregnant and puerperant women have been studied. The species composition of the community, the population size and occurrence of each species, its participation in the dominant structure of the community have been determined. The comparative evaluation of its types has been made. A decrease in the dominating role of M. luteus in pregnant and puerperant women has been established. The tendency towards the normalization of the structure of the community in the postnatal period has been established.     

Changes in the functional organization of the respiratory system in residents of Western Siberia in the winter season

The respiratory parameters of healthy young men from Western Siberia have been examined. The correlations between the parameters have been analyzed, and the functional structure of the respiratory system in summer and winter has been identified. It has been found that different regulatory programs operate depending on the temperature of the inhaled air. The study has shown that the changes in the oxygen demand of the body in summer are mediated by the changes in the volume of pulmonary ventilation (“ventilation” or “summer program”). In winter, when maintaining the level of energy processes in the body is in conflict with maintaining thermal homeostasis in the respiratory regions of the lungs, pulmonary ventilation becomes limited, and the number of functioning lung units is reduced. At the same time, in compensation, the lung diffusion capacity increases (“diffusion” or “winter program”). This means that the functioning of the apparatus of external respiration is optimized in winter.     

Difference in the maturation of the three-domain vasopressin precursor in the guinea-pig and rat: identification of a neurophysin-copeptin fragment in the guinea pig

Vasopressin, MSEL-neurophysin and copeptin have been isolated from guinea pig and rat neurophypophyses and their amino acid sequences have been determined. Whereas in rat processing of the three-domain precursor is complete, in the guinea pig a 132-residue fragment including MSEL-neurophysin and copeptin linked by an arginine residue has been characterized. This incomplete maturation (20% of the precursor) could be due to a deletion of an acidic residue in guinea pig copeptin when compared with other mammalian copeptins.     

The role of the carboxamide group in nicotinamide adenine dinucleotide in relation to hydride transfer: the reduced form of the dinucleotide as remedy in the modulation of neurotransmission

The stereochemical significance of the carboxamide group in combination with the ring nitrogen in NADH-NAD+ conversions has been demonstrated. This has been shown in model systems as well as under enzymatic conditions. The role of the carboxamide group in selective regiospecific interactions has been discussed for neurodegenerative diseases.     

Structure and function of the genes involved in the biosynthesis of carotenoids in the mucorales

Carotenoids are widely distributed natural pigments which are in an increasing demand by the market, due to their applications in the human food, animal feed, cosmetics, and pharmaceutical industries. Although more than 600 carotenoids have been identified in nature, only a few are industrially important (β-carotene, astaxanthin, lutein or lycopene). To date chemical processes manufacture most of the carotenoid production, but the interest for carotenoids of biological origin is growing since there is an increased public concern over the safety of artificial food colorants. Although much interest and effort has been devoted to the use of biological sources for industrially important carotenoids, only the production of biological β-carotene and astaxanthin has been reported. Among fungi, several Mucorales strains, particularlyBlakeslea trispora, have been used to develop fermentation process for the production of β-carotene on almost competitive cost-price levels. Similarly, the basidiomycetous yeastXanthophyllomyces dendrorhous (the perfect state ofPhaffia rhodozyma), has been proposed as a promising source of astaxanthin. This paper focuses on recent findings on the fungal pathways for carotenoid production, especially the structure and function of the genes involved in the biosynthesis of carotenoids in the Mucorales. An outlook of the possibilities of an increased industrial production of carotenoids, based on metabolic engineering of fungi for carotenoid content and composition, is also discussed.     

Effect of myelopeptides on the synthesis of DNA and total protein in the cells of the lymphoid organs in the mouse

Using double 3H-thymidine/14C-amino acid label, the influence of myelopeptides (MP) on chromosomal DNA and total protein (without histones) synthesis has been studied in vitro in mouse lymphoid organ cells. It has been shown that MP cause a decrease in DNA labelling and a parallel increase in protein labelling in bone marrow cells and have practically no effect on these two parameters in thymus, lymph node and spleen cells. It has been found that MP have only mitogenic effect on the above-mentioned organ cells, but in combination with 2-mercaptoethanol. The data obtained show that MP possess the properties of cell-differentiating factors.     

Results of the cytogenetic examination of the people taking part in the clean-up of the accident at the Chernobyl AES]

Chromosome preparations from peripheral blood cells of 117 subjects who took part in liquidation of Chernobyl NPP accident consequences in 1986 have been investigated. The number of chromosome aberrations has been shown to increase considerably. A short-term exposure has been found to be 5-7 times more effective than long-term one.     

Variations in the middle ear of the Mammalia

The comparative morphology of mammalian middle ear structures has been studied by examining the histological sections of the ears of 144 specimens of mammals which had been collected, with a few exceptions, in two expeditions to the Caribbean area. Fifty-four species of six orders of mammals were represented. Sixteen structural features or relationships were specifically studied and the bearing of taxonomic groupings on the variability was analysed.
A taxonometric analysis using these middle ear features indicated that Microdipodops may lie nearer to Dipodomys than to Perognathus.
A table presenting the detailed results has been deposited with the British Museum (Natural History).     

Measurement of the spontaneous motility in vitro of the floor of the reticular sulcus in cattle

The bases and the parameters which define the smooth muscle spontaneous motility of the reticular groove floor in cattle have been established. The study has been carried out in 27 esophageal grooves in a classic organ bath technique. The results show a recognizable own spontaneous motility with two kinds of contractions: high tension ones and others with smaller contraction intensity. The young animal parameter values are different from those of grown-up ones. In adults, these values depend on the muscular dissection belt.     

Multivariate approach to the analysis of the growth processes in the peripuberty period of human ontogeny

Factor analysis by principal components with the Warimax rotation has been conducted on 26 anthropometric traits of 2200 children aged 6.75 to 17.25. Mean values of traits have been calculated at half-year intervals within each sex. Two orthogonal components accounting 96.5% of the total variation have been chosen. Individual factor values have been analysed to determine their relationship with age. The classification of objects is constructed by the cluster analysis in the space of factors. Four different morphological types within each sex have been found. The age limits between the revealed clusters differ for both sexes.     

Cultivation of the gonococcus in nutrient broths

The dynamics of the multiplication of gonococci and the parameters of their growth have been studied in the process of batch cultivation in liquid culture media with different content of bovine blood serum. The protective and stimulating action of the serum on the growth of gonococci has been shown. The optimization of the process of cultivation has been carried out; as a result, the growth of test strains in a culture medium containing no serum has been achieved. Phasic changes in the ultrastructure of gonococci in the process of their cultivation in liquid media have been followed. 9- to 12-hour cultures of gonococci grown in liquid culture media have been found the most valuable and physiologically active.     

Use of Ranks in Comparisons of Variability in the Non-Normal Populations

A method of analysis for comparing the variability of two samples drawn from two populations has been developed. The method is also suitable for the nonnumeric form of data. A test based on ordered observations for testing the null hypothesis of equality of two variances has been given. The test statistic is a function of the sum of ranks assigned to smaller size sample. Ranking procedure has been modified to depict the variability in the data by the sum of ranks. The null distribution of the test-statistic has been worked out for small samples and it turns out to be chi-square distribution for large samples. The analytical procedure has been explained by a numerical example on the productivity and production of rice and wheat in India from 1950–51 to 1983–84.     

Ethological approach in the study of aggressive behavior in monkeys

The aggressive behavior of 7 species of monkeys has been investigated. The definition of aggressive behavior has been suggested. The elements have been classified into three groups: warning, conflicting, contacting. The qualitative and quantitative characteristics of behavior permitting to determine the level of its development in representatives of different species have been proposed. The general principles of development of aggression such as the prevalence of the warning elements and its frequency, the curtailment of aggressive behavior etc. have been revealed. The differences in the aggressive behavioral characteristics are found to be specific and may be used in primate Taxonomy.     

Generational variability in the patterns of motor activity circadian rhythm in the rats

Motor activity circadian rhythm of 32 rats belonging to three consecutive generations of rats from a laboratory strain, has been studied. This rhythm has been registered from the day of weaning (at 21 days) to at least 30 days after. The pattern of this rhythm has been analyzed by means of a Fourier analysis, by which the daily power spectrum of each rat was obtained. Based on the mean power spectrum of each animal, the variance among the different families and generations has been calculated. Results show that the variance increases in a statistically significant way with the succeeding generations. It can be suggested that in the third generation, the characteristics of the progenitors are dispersed, confirming the genetic character of the rhythm and suggesting a multigenic character for the transmission of the circadian rhythm of motor activity.     

The mechanism of the development of the epidemic process in Sonne dysentery

An epidemic outbreak of Sonne dysentery has been studied. The data of epidemiological monitoring before and after the epidemic have been analyzed. The real prognostication value of controlling the biological properties of Shigella sonnei and the increase of their intrapopulation heterogeneity at the period of the activation of the epidemic process of Sonne dysentery has been established.     

Characteristics of the phenotypic variability in the levels of DNA autoantibodies in healthy persons

Peculiarities in the distribution of autoantibody levels to native and denervated DNA have been studied. A considerable distribution of genetic factors to phenotypic variability of the traits in question has been shown. Increased levels of the investigated autoantibodies correlated with HLA-A3, B35, decreased--with HLA-A10, B17.     

Biological activity in vivo of insulin analogues modified in the N-terminal region of the B-chain

[AlaB5]Insulin as well as a hybrid analogue of insulin and "insulin-like growth factor" (IGF-I), in which the N-terminal amino-acid sequence H-Phe-Val-Asn-Gln- of the B-chain has been replaced by the tripeptide H-Gly-Pro-Glu-of IGF-I, have been prepared by the partial-synthetic route. Their biological activity in vivo has been compared with that of other analogues in rabbits, mice and rats as far as data are available. These rodents respond differently, rats being less sensitive to modifications than rabbits and mice. The results explain unexpected discrepancies discussed in previous papers.