Combined effect of normobaric hyperoxia and vibration on the radiosensitivity of animals

In experiments with hybrid mice (CBA X C57B1)F1 and F2(CBWA), a study was made of the combined effect of normobaric hyperoxia and vibration on sensitivity of the organism to gamma-radiation. A single and protracted (for 5 days, daily) vibration before irradiation aggravated acute radiation sickness. A modifying effect of hyperoxia on the development of the intestinal form of radiation sickness was the same as that observed under the effect of vibration. In the experiments with tetrahybrids, the combined effect of the two factors aggravated drastically the intestinal syndrome of acute radiation sickness (DMF = 1.24).     

Effect of vibration on gamma-aminobutyric acid metabolism in the brain in various functional conditions of the adrenal cortex]

The low-frequency vibration during 30 min (20 Hz, A = 0.4 mm) has been studied for its influence on the level of components of the GABA system and dicarbonic ++amino acids in male rats at hypo- and hyperfunction of the adrenal cortex. It is shown that under these conditions of the experiment the GABA level and glutamate-decarboxylase activity increase. Hyperfunction of the adrenal cortex against the background of vibration causes a relatively less pronounced increase in the GABA content, than the vibration alone or against the background of inhibition of adrenocortical function in the organism.     

Stressogenic exposure of local vibration to energetic metabolism of the heart, liver and kidney of rats

The purpose of the paper was to study the activity of energy producing system of the rabbit myocardium, liver and kidneys after exposure to local vibration during 7 days. The energy dependent reactions of native mitochondria were investigated by means of polarographic method using dark closed membrane electrode. The intensivity ofoxydative processes was assessed according to activity of the lymphocyte succinate dehydrogenase and catalase of the blood. The energy producing system of the tissues studied was shown to be involved in response reaction of the organism on vibration exposure. In that case we observed the formation of the second phase ofbioenergy hypoxia in the myocardium and kidneys and the first phase ofhypoxia in the liver.     

Comparative analysis of spontaneous unit activity of the cerebellum fastigial nucleus' neurons in different periods of vibration influence

In conditions of acute experiment on white rats anaesthetized with Nembutal (40 mg/kg, interperitonially) recording and analysis of spontaneous impulse activity of the fastigial nucleus' neurons in norm and after 5, 10 and 15 days of vibration influence on the organism were carried out. Distribution of the neurons was evaluated by the dynamics of neuronal current flow and the modality of the interspike interval hystograms, as well as the statistical parameters: the average discharge frequency and the coefficient of the interspike interval variation. It is shown that more significant changes in neuronal activity of fastigial nucleus cells are formed during the first 10 days of vibration influence. On the 15th day, there was a tendency towards return to control levels of the parameters under study.     

Effect of thrombin on the arterial blood pressure level and on cardiac activity in rats

The influence of the thrombin intravenous injection on the level of the arterial pressure of nonanaesthetized rats has been studied. It has been found out that different doses of thrombin cause two phases vibration of pressure: rapid decrease and slower increase of arterial pressure. Hexenal anaesthesia does not change degree and speed of pressure decrease but reduces the restoration of the initial level and eliminates the increasing pressure phase. The effect grows with the thrombin dose increasing and sharply reduces under anaesthesia. The interrelation of the phenomena established and the adaptive significance for living organism is being discussed.     

Effects of Calcium on Sugar Transport in Azotobacter vinelandii

A fast and environmentally safe procedure was used to study sugar uptake by Azotobacter vinelandii. Transport experiments were performed in a 24-well plate and aerated by rapid oscillatory vibration. Samples were washed by centrifugation and dissolved in biodegradable scintillation cocktail for counting. At cell concentrations up to 6 × 10⁸ cells per ml, the uptake of sucrose was a function of time and was proportional to the cell concentration. This modified uptake assay was used to test the effect of cations on sugar uptake in A. vinelandii. Results showed that Ca²⁺ at 1 to 2 mM stimulated sucrose uptake by decreasing the apparent K_m of sucrose transport. Higher Ca²⁺ concentrations inhibited sucrose uptake in this organism.     

Evaluation of human strain during interrupted exposure to vibration (author's transl)

The psychophysical reactions to stochastic vibrations transmitted in vertical direction to sitting man are investigated in simulated experiments under laboratory conditions. In the framework of an appropriate concept of assessment, indicators related to bottleneck situations in functional systems of the organism for activity and strain measurements allow the evaluation of the recreation efficiency of interruptions in exposure time. The special meaning of the distribution and thus the frequency rate of the interruptions can be illustrated particularly by the variance in time of the strain processes of selected muscles. Between the degree of muscle fatigue and the period of uninterrupted exposure time (expressed in "exposition-interruption-distribution") a significant correlation results so that numerous interruptions of vibration exposure should be considered as a profitable guideline for work design with respect to ergonomics.     

Mechanism of action of dialkylaminoethylthiol derivatives of pyrimidine and quinazoline

A study was made of acute toxicity and radioprotective efficiency of some heterocyclic isothiuronium analogues and their ability to change the oxygen uptake by the organism. The rate of hydrolysis of the preparations in vitro was determined. A correlation was found between the above-mentioned indices. On the basis of the data obtained it was concluded that aminothiol, formed as the result of enzymic digestion in the organism, was responsible for the radioprotective effect of the compounds under study since it reduced the oxygen uptake by the organism.     

The acute effects of mechanical vibration on power output in the bench press

This study was designed to investigate the effect of mechanical vibration on acute power output in the bench press exercise. Ten male subjects who were experienced in resistance training participated in this study. Each subject performed 3 sets of 3 repetitions in the bench press exercise using a load equal to 70% of 1 repetition maximum in each of 2 sessions separated by 3 days. One session served as the experimental (vibration) condition, whereas the other session served as the control (no vibration) condition. The intervention (vibration or control) was applied between sets 2 and 3. The vibration was applied by a vibrating barbell apparatus held by the subjects while lying supine on a bench. The only difference between the 2 conditions was the vibration of the barbell apparatus during the vibration condition. Peak and average power were calculated during each bench press set to determine whether power output differed following vibration compared to control. Average power was significantly higher for the vibration condition compared to the control (525 +/- 74 vs. 499 +/- 71 W; p = 0.01). There was also a trend toward an increase in peak power in the vibration condition (846 +/- 168 by vs. 799 +/- 149 W; p = 0.06). In general, peak and average power output were higher following the vibration intervention compared to control. However, the sets prior to vibration application during the vibration condition also demonstrated higher power outputs compared with the control condition, which contributed to the main effect for the vibration condition. These results suggest that factors other than the vibration intervention influenced task performance during the vibration condition. We suggest that psychological factors related to the novelty of the vibration intervention were involved. These factors may partially explain the conflicting results of previous investigations that examined vibration as an exercise intervention.     

The theory of organism and the culturalist foundation of biology

Summary After the disappearance of organism was diagnosed, the discussion about the role of a theory of organism in biology is characterised by a significant contradiction. On the one hand, the importance of a theory of organism is stated. Particularly developmental biology demands organism-centred approaches as a basis for conceptual integration. On the other hand, several modern biological disciplines such as genetics and molecular biology simply don’t need a theory of organism for their work. Consequently, the determination of the status of the organism and its relevance for biology at all is an unsolved problem. In order to clarify the methodological status of the organism in biology we start with the reconstruction of three important propositions. A life oriented approach and a hierarchy concept - which both are from a neo-Darwinian origin - are confronted with a structuralist approach of organism, that can be characterised as a non-Darwinist approach. Our own attempt for the solution of the organism problem applies the tools of culturalist methodology. In accordance to this pragmatic approach, the term organism is introduced as a concept of notion. A constructional morphological case study exemplifies the applicability of this concept. From the culturalist point of view a methodological foundation of biology can be achieved, that provides a consistent basis for a comprehensive integration of biological knowledge.     

Comparison of morphological characteristics of Streptomyces natalensis by image analysis and focused beam reflectance measurement

A morphological interpretation is presented for data collected during growth of a filamentous organism, using a focused beam reflectance measurement (FBRM) system. The morphology of the organism was also obtained using conventional semiautomatic image analysis to support the interpretation of the FBRM data. The model organism employed is the filamentous soil-borne actinomycete Streptomyces natalensis, which produces the antifungal agent pimaricin. The organism was cultivated both in shake flasks and in a bench-scale stirred tank bioreactor. It was found that FBRM could be used to track changes in the morphology of the organism throughout the course of its growth on both scales. These changes were highlighted using both the median chord length and length-weighted mean chord length obtained from the chord length distribution measured with the FBRM probe. The ability of the FBRM probe to respond to changes in both the size and morphology of mycelial aggregates was supported by standard image analysis parameters, including equivalent diameter, convex area, and compactness.     

Effects of extreme factors and antioxidant alpha-tocopherol on the intensity of blood plasma chemiluminescence]

It was established in experiments on rats that intensity of "fast flash" of iron-induced chemiluminescence of biological samples containing microvolumes of blood plasma correlate with resistance of organism to severe hypoxia. The new method is promising for the estimation of the sensitivity of intact organism to severe hypoxia, for registration of antioxidant therapy effects and for studying the mechanisms of extreme factors influence on the organism.     

泰泽病原体基因组DNA提取方法的建立

目的　提取泰泽病原体基因组DNA ,为建立该菌基因组文库奠定基础。方法　使用密度梯度离心结合酶解消化方法、酶解消化方法、本研究建立方法即过滤盐析离心法 ,从感染肝脏组织纯化泰泽病原体 ,并比较三种方法纯化泰泽病原体效果 ;采用氯化苄法、试剂盒、酚法提取泰泽病原体基因组DNA ,并比较三种方法提取基因组DNA质量 ;鉴定酚法提取泰泽病原体基因组DNA特异性。结果　使用过滤盐析离心法从感染肝脏组织纯化泰泽病原体 ,采用酚法提取其基因组DNA ,所获得的基因组DNA特异性好、纯度高、DNA片段长度大于 5 0kb ,且均一性好 ,无降解。结论　本研究首次成功提取泰泽病原体基因组DNA ,可用于多种分子生物学实验     

Reduction of Saccharomyces cell adhesion by liquid mechanical vibration

The effect of liquid mechanical vibration on the adhesion of Saccharomyces cerevisiae cells to the internal glass surface of a pipette was studied using a 25 Hz vibration source. The maximum vibration amplitude was 1.06 mm (peak to peak) along the pipette direction. Relative movements between the pipette and yeast suspension in it were produced by vibration and reduced the cell adhesion. The reduction in adhesion was affected by both vibration amplitude and suspension pH. Analysis showed that in routine cell counts, cell adhesion to the pipette wall was a significant error source. The construction of a vibration device for routine cell count work appears feasible.     

Inhibition of Autoagglutination of Moraxella bovis by 10% Magnesium Chloride

A 10% solution of magnesium chloride was used to uniformly disperse Moraxella bovis, an organism that autoagglutinates in most liquid media. The magnesium chloride did not affect the viability or morphology of this organism.     

Characteristics of S Organism Isolated from Methanobacillus omelianskii

Previous work showed that Methanobacillus omelianskii was a mixed culture of an ethanol-oxidizing organism called S organism and a hydrogen-utilizing methane bacterium, strain MOH. S organism grows poorly on ethanol unless a hydrogen-utilizing methanogenic bacterium is included to utilize the H(2) produced during growth. Further studies have shown that, among many substrates tested, only ethanol, n-propanol, n-butanol, isobutanol, n-pentanol, acetaldehyde, oxalacetate, and pyruvate are fermented by S organism, either alone or in combination with Methanobacterium ruminantium. It grew better in pure culture with pyruvate than with alcohols. H(2) gas phase inhibited growth on pyruvate as well as on alcohol. When grown alone on pyruvate, S organism produced mainly acetate, ethanol, and CO(2), in addition to a small amount of H(2). When combined with M. ruminantium, no H(2) and very little ethanol were produced and acetate production was increased. When M. ruminantium was present, electrons from pyruvate oxidation by S organism were channeled almost entirely to H(2) and hence to methane formation rather than ethanol. Also, S organism utilized more pyruvate when grown with M. ruminantium. Attempts to obtain better growth of S organism on ethanol by addition of many possible electron acceptors were unsuccessful. It grew best between 32 and 45 C, had a per cent guanine plus cytosine content of deoxyribonucleic acid bases of 47.27 +/- 0.1, contained no cytochrome, and could be grown on a defined medium with pyruvate as the energy and carbon source and with (NH(4))(2)SO(4) as the main nitrogen source. These and other results suggest that S organism belongs in a new genus, but assignment of a definite taxonomic status should await isolation and characterization of more strains.     

Effect of thermal selection of the male gametes on the resistance to temperature and chlorophos of the body and muscles in tadpoles of the common frog

A study was made of the effect of thermal selection of parental spermatozoa on the heat resistance of the whole organism and of muscles in progeny of Rana temporaria, as well as of the organismal resistance to pesticides (0.0025 M chlorophos). The thermal selection of spermatozoa was performed by exposing their suspension to 36 degrees C for 30-40 minutes. With tadpoles, the resistance of muscles to 38 degrees C, was determined, in addition to the resistance of the organism to 34 degrees and to 0.0025 M chlorophos. The results of selection were stage--specific: at stages of growth (stages 39, 42, 50) the heat resistance of the organism was lower and that of muscles was higher than in controls. At the stage of metamorphosis proper (stage 52) the heat resistance of both the organism and muscles increased. The thermal selection of parental spermatozoa exerted no effect on the resistance of the progeny to 0.0025 M chlorophos.     

Effect of chest wall vibration on breathlessness in normal subjects

This study evaluated the effect of chest wall vibration (115 Hz) on breathlessness. Breathlessness was induced in normal subjects by a combination of hypercapnia and an inspiratory resistive load; both minute ventilation and end-tidal CO2 were kept constant. Cross-modality matching was used to rate breathlessness. Ratings during intercostal vibration were expressed as a percentage of ratings during the control condition (either deltoid vibration or no vibration). To evaluate their potential contribution to any changes in breathlessness, we assessed several aspects of ventilation, including chest wall configuration, functional residual capacity (FRC), and the ventilatory response to steady-state hypercapnia. Intercostal vibration reduced breathlessness ratings by 6.5 +/- 5.7% compared with deltoid vibration (P less than 0.05) and by 7.0 +/- 8.3% compared with no vibration (P less than 0.05). The reduction in breathlessness was accompanied by either no change or negligible change in minute ventilation, tidal volume, frequency, duty cycle, compartmental ventilation, FRC, and the steady-state hypercapnic response. We conclude that chest wall vibration reduces breathlessness and speculate that it may do so through stimulation of receptors in the chest wall.     

Effect of temperature and salinity on Vibrio (Beneckea) vulnificus occurrence in a Gulf Coast environment.

Vibrio (Beneckea) vulnificus is a recently recognized halophilic organism that may cause serious human infections. Patients infected with V. vulnificus often have a history of exposure to the sea, suggesting that the organism may be a common inhabitant of marine environments. Twenty-one inshore sites around Galveston Island in the Gulf of Mexico were cultured for V. vulnificus over a 12-month period. The organism was recovered from all but one of the sites at some time during the study. It was frequently isolated during the summer and fall from environments of relatively low salinity (7 to 16%). V. vulnificus was rarely isolated from any of the sites during the winter months, when water temperatures dropped below 20 degrees C. In vitro growth characteristics of environmental isolates of V. vulnificus demonstrated salinity optima of 1.0 to 2.0% NaCl and a temperature optimum of 37 degrees C. These growth characteristics may account for the seasonal and geographical variations in occurrence of the organism. Overall, the results of these studies indicate that V. vulnificus is commonly found in Gulf Coast environments and that the occurrence of the organism is favored by warm temperatures and relatively low salinity.