The role of ligands in the effect of exposure to ionizing radiation on Ca2(+)-ATPase and Mg2(+)-ATPase

Over the past year, a number of advances have been made in the large-scale purification of macromolecules, particularly proteins. Although refinements to individual unit operations have occurred, especially in improving the speed of operation and performance of large-scale chromatographic media, a major research thrust has been the development of processes in which steps are combined or eliminated to improve operability and reduce cost.     

The population dynamics of Salmonella typhi and Tetrahymena pyriformis during joint cultivation

Scientific researches carried out in the area of environmental sanitation are closely related to the principal lines of activity in industry and farming of Ukraine. The main task of research work is establishing principles, criteria and methods of comprehensive assessment of injury to health secondary to environmental contamination. With the purpose of identification of the real physical and chemical environmental factors load that human body experiences, an inventory has been made at the Ukrainian Scientific Research Centre for Hygiene of carcinogen sources, with the concept having been worked out of creation of the integrated system for control of safe NPS operation, and a concept proposed of genetic monitoring, and of state genetic load surveillance service in different regions of Ukraine, taking account of the degree of environmental pollution.     

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.     

An integrated evaluation of the adaptation system and existing risk factors as a method for the objective assessment of the efficacy of sanatorium-health resort treatment

It has been shown that antihemolytic effect of trifluoroperazine is realized directly at the stage of hyperosmotic stress during cell transfer to 4.0 M NaCl and is not the result of preliminary cell treatment by this amphypathic compound. The value of protecting effect of trifluoroperazine is determined by preliminary RBS dehydration condition. Cell treatment by hemin, modifying cytoskeleton and membrane, significantly affects cell sensitivity to hyperosmotic stress both in the presence of trifluoroperazine and without the latter.     

Inadequate weight gain among pregnant adolescents: risk factors and relationship to infant birth weight

OBJECTIVE: Our purpose was to identify behavioral markers for inadequate weight gain (< 20 pounds) during pregnancy among adolescents < 18 years old. STUDY DESIGN: A total of 337 adolescents who were delivered of a term infant at our institution between March 10, 1992, and November 28, 1994 participated in this study. A comprehensive structured interview conducted at the first prenatal visit elicited demographic information and behavioral risk factors. Maternal weights, reproductive history, evidence of sexually transmitted disease, and infant birth weight were extracted from medical records. Logistic regression and chi 2 analyses compared characteristics and infant birth weights between those who gained < 20 pounds with those who gained > or = 20 pounds. RESULTS: A total of 11.6% (39/337) of the total sample gained < 20 pounds during the pregnancy. Adolescents who gained < 20 pounds compared with > or = 20 pounds were delivered of significantly lighter (2942 gm vs 3392 gm) infants and were more likely to be delivered of infants weighing < 2500 gm (13% vs < 1%). Stepwise logistic regression revealed that adolescents who were battered (odds ratio 5.3) or had a sexually transmitted disease (odds ratio 2.3) or an unplanned pregnancy (odds ratio 8.1) were at increased risk for insufficient weight gain during pregnancy. CONCLUSION: Our data suggest that behavioral risk factors are important in the identification of adolescents at greatest risk for inadequate weight gain. Early identification during pregnancy is essential to modify nutritional practices and thus minimize poor obstetric outcomes.     

The photoreceptors and visual pigments of the garter snake (Thamnophis sirtalis): a microspectrophotometric, scanning electron microscopic and immunocytochemical study

Scanning electron microscopy, immunocytochemistry, and single cell microspectrophotometry were employed to characterize the photoreceptors and visual pigments in the retina of the garter snake, Thamnophis sirtalis. The photoreceptor population was found to be comprised entirely of cones, of which four distinct types were identified. About 45.5% of the photoreceptors are double cones consisting of a large principal member joined near the outer segment with a much smaller accessory member. About 40% of the photoreceptors are large single cones, and about 14.5% are small single cones forming two subtypes. The outer segments of the large single cones and both the principal and accessory members of the doubles contain the same visual pigment, one with peak absorbance near 554 nm. The small single cones contain either a visual pigment with peak absorbance near 482 nm or one with peak absorbance near 360 nm. Two classes of small single cones could be distinguished also by immunocytochemistry and scanning electron microscopy. The small single cones with the 360-nm pigment provide the garter snake with selective sensitivity to light in the near ultraviolet region of the spectrum. This ultraviolet sensitivity might be important in localization of pheromone trails.     

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.