The work experience of the medical service of the Moscow Military District in personnel health protection]

Reforming and downsizing of the Armed Forces, forming up its new infrastructure place new complicated tasks for the medical service of the Moscow military district. It focuses its efforts on the most urgent social problem--the health care of personnel, which is the main component of the combat strength. In 1997 the personnel of military units that had a higher level of morbidity underwent non-specific prophylactic procedures, resulting in a reduced number of cases and follow-up complications. Due to some command measures developed, the young recruits were able to adapt themselves to the army environment faster than before. A number of directives were issued to improve sanitary-epidemiological situation in some garrisons. A series of new programmes help to reduce personnel morbidity by improving their living and working conditions and to strengthen overall security.     

Adaptive response in vivo: reasons for increase of radioresistance in CFU-S

The data concerning the reasons of CFU-S radioresistance increase after low dose irradiation of mice were obtained; the reparation processes in CFU-S adapted by low dose irradiation were shown to be more active than in intact ones. Colony formation increase was demonstrated to be more pronounced in adapted animals when they had been injected by 50 mcg of synthetic polyribonucleotide PolyI-PolyC two days before irradiation in challenge dose. The thymogen immunomodulator administration to adapted and intact donor animals leads to the increase of colony yield in equal extent.     

Colonic dysfunction in acute diarrhoea: the role of luminal short chain fatty acids

Faecal concentrations and output of short chain fatty acids (SCFA) were assessed on successive days by gas-liquid chromatography in 24 patients with acute watery diarrhoea. Absorption of water and sodium from the rectum was also measured by a dialysis technique in 17 of these patients and in nine normal subjects in the presence and absence of luminal SCFA. Faecal SCFA concentrations were low on the first day of diarrhoea (mean (SEM) 9.9 (5.8) mmol/kg) and increased to 94.8 (16.4) mmol/kg by the fifth day. Faecal output of SCFA corresponded to these figures. Net water absorption, in the absence of luminal SCFA, was stopped in patients with acute diarrhoea (-59 (81) nl/cm2/min) compared with healthy controls (+322 (63) nl/cm2/min) (p < 0.01). Luminal SCFA restored net water absorption to +184 (67) nl/cm2/min in patients with acute diarrhoea (p < 0.01). Net absorption of sodium decreased in patients with acute diarrhoea in the absence of luminal SCFA, but returned to normal with luminal SCFA. Net secretion of potassium increased in acute diarrhoea, and did not change in the presence of SCFA. Defective absorption from the rectum in acute diarrhoea is reversed by luminal SCFA. The reduction of luminal SCFA in acute diarrhoea treated conventionally may be a factor contributing to colonic dysfunction.     

The surgical treatment of heart valve defects combined with multiple coronary artery involvement

The authors analyze 144 surgeries in patients with single and multiple valvular defects combined with multiple involvement of the coronary arteries; multiple (3-4) coronary artery shunting was carried out in 21 patients, the mortality being 19.4%. Recovery of the blood stream in all involved coronary arteries and correction of defective valves were found conducive to reduction of incidence of myocardial infarction and acute heart failure. Retrograde blood cardioplegia to a considerable measure shortened the duration of aorta clamping and improved myocardial protection. Such methods and improvement of surgical technique helped us reduce the mortality rate by 2-3 times.     

Genotoxic modification of nucleic acid bases and biological consequences of it. Review and prospects of experimental and computational investigations

The review is presented of experimental and computational data on the influence of genotoxic modification of bases (deamination, alkylation, oxidation) on the structure and biological functioning of nucleic acids. Pathways are discussed for the influence of modification on coding properties of bases, on possible errors of nucleic acid biosynthesis, and on configurations of nucleotide mispairs. The atomic structure of nucleic acid fragments with modified bases and the role of base damages in mutagenesis and carcinogenesis are considered.     

Structural requirements of the higher order RNA kissing element in the enteroviral 3'UTR

The origin of replication ( oriR ) involved in the initiation of (-) strand enterovirus RNA synthesis is a quasi-globular multi-domain RNA structure which is maintained by a tertiary kissing interaction. The kissing interaction is formed by base pairing of complementary sequences within the predominant hairpin-loop structures of the enteroviral 3' untranslated region. In this report, we have fully characterised the kissing interaction. Site-directed mutations which affected the different base pairs involved in the kissing interaction were generated in an infectious coxsackie B3 virus cDNA clone. The kissing interaction appeared to consist of 6 bp. Distortion of the interaction by mispairing of each of the base pairs involved in this higher order RNA structure resulted in either temperature sensitive or lethal phenotypes. The nucleotide constitution of the base which gaps the major groove of the kissing domain was not relevant for virus growth. The reciprocal exchange of the complete sequence involved in the kissing resulted in a mutant virus with wild type virus growth characteristics arguing that the base pair constitution is of less importance for the initiation of (-) strand RNA synthesis than the existence of the tertiary structure itself.