The intensity of the peroxidation of lipids and their fatty acid composition in Drosophila melanogaster strains differing in their adaptive value

An attempt was made to explore the myeloperoxidase (MPO) activity in medium used for incubation of peripheral venous blood (PVB) leukocytes from patients with gingivitis and periodontitis and to compare it with that of periodontally healthy subjects. The study population included 54 gingivitis patients (G), 52 periodontitis patients (P) and 52 control subjects (C). All these groups were assessed by clinical, laboratory and statistical methods. The leukocytes were incubated with opsonized zymosan, Escherichia coli ATCC25922, nonopsonized E.coli or Staphylococcus aureus 256. The respective levels of MPO activity in incubation media of PVB leukocytes taken from group G patients were 598.0 +/- 29.2 conventional units (c.u.), 640.0 +/- 26.3 c.u., 662.0 +/- 37.6 c.u. and 750.0 +/- 40.8 c.u. (control incubation medium: 564.0 +/- 25.1 c.u.); those for group P patients were 672.0 +/- 34.3 c.u., 678.0 +/- 43.1 c.u., 692.0 +/- 47.9 c.u. and 762.0 +/- 34.7 c.u. (control: 612.0 +/- 35.2 c.u.); those for group C subjects were 556.0 +/- 30.2 c. u., 714.0 +/- 28.2 c.u., 1276.0 +/- 69.0 c.u. and 794.0 +/- 47.1 c.u. (control: 534.0 +/- 29.0 c.u.). MPO activity was increased most significantly when nonopsonized E.coli was added to the incubation medium of PVB leukocytes taken from subjects with intact periodontium. MPO activity was unchanged when the leukocytes were taken from periodontitis patients.     

Functional features of wind-sensitive receptors triggering the wing muscle neurons of the desert locust, Calliptamus barbarus]

At each side of the head of C. barbarus, 5 receptive fields were found triggering the activity of neurons which directly control the work of wing apparatus. Total number of wind-sensitive receptors (presented by trichoid sensillae) amounts up to 200. Lateral receptive fields 1 and 5 are most developed and contain 24 +/- 5 and 23 +/- 4 sensillae respectively. In the response of a receptor to adequate stimulation, two components may be differentiated--phasic and tonic ones. The discharge frequency of the tonic component is equal to 90--100 impulses per sec. Simultaneous recording of impulse activity in axons of two receptors reveals a possibility of interaction of the receptors. In the experiments performed, this peripheral interaction was of the inhibitory nature. Functional peculiarities of the receptor investigated are discussed.     

Coliphages as indicators of viral pollution of water supply

The paper presents the data of Russian and foreign authors, as well as these author's findings of the significance of coliphages as indicators of viral contamination of drinking water. Coliphages may be used as indicators of viral drinking water contamination and for evaluation of the efficiency of drinking water purification in waterworks.     

A comparison of the contractile properties of the muscles of the lower extremities in man

The physiological features of two antagonistic muscle groups, the dorsiflexors and plantar flexors of the ankle, have been compared in 11 healthy subjects aged 15-17 years (+/- SE; 16 +/- 1.2 years). Contractile properties of plantar flexors of the foot, namely of tibialis anterior (TA) and extensors triceps surae (TS) have been estimated by mechanical parameters of voluntary and electrically evoked contractions. All test subjects exhibited tolerance to supramaximal force of electric stimulation of n. tibialis and n. peroneus profundus at a frequency of 150 impulses.s-1 (for TS) and 150 impulses.s-1 and 250 impulses.s-1 (for TA). TA displayed high velocity and force-velocity properties (p < 0.05-0.001); TS had high force parameters (p < 0.05-0.01). The magnitude of force deficiency observed during voluntary contraction of these muscles is lower in TA and higher in TS (p < 0.05). The results permit supposing that differences in contractile properties of the muscles under study depend on a various specific contribution of peripheral and CNS factors.     

Current aspects of creation of expert systems in aviation medicine

Topical directions of developing the medical expert systems (MES) are considered. The problems to be solved by using programming and informational means as part of MES are discussed. A classification of the knowledge of expert physicians who directly deal with decision making is proposed. The characteristics of the developed MES well appreciated by the results of their operation are given. They show new trends associated with the update of medical knowledge and the developmental level of information technologies.     

Cloning of ribR, an additional regulatory gene of the Bacillus subtilis riboflavin operon

A 13.0-kb EcoRI fragment of Bacillus subtilis DNA carrying an additional regulatory ribR gene of riboflavin operon was cloned on the basis of resistance to 7, 8-dimethyl-10 (O-methylacetoxym)-isoalloxasin. The cloned fragment was trans-dominant with regard to ribC constitutive mutations that block the overproduction of riboflavin but inactive relative to constitutive mutations in the rib(O) regulatory region.