Indoor radon concentrations in Poland as determined in short-term (two-day) measurements.

The aim of the present work was to obtain a pattern of 222Rn concentration distributions in typical buildings in Poland. In the investigations, the environmental passive detectors of the PICO-RAD type were used. The study encompassed buildings that were typical for Poland. The distribution of airborne 222Rn concentrations indoors is of a log-normal type. A total 1171 detectors were measured. Measurements were made in 319 basements, the remaining 852 measurements were carried out in the inhabited part of the houses. The radon concentrations in the basements in Bq x m(-3) ranged from 6 to 1300 with the arithmetic mean AM = 60, geometric mean GM = 30 and median M = 28, whereas those in the inhabited parts of the house (above the ground level) were: AM = 25, GM = 17 and M = 16 with the highest record value of 420.

Study of 222Rn concentrations in drinking water in the north-eastern hydroregions of Poland.

This paper presents the results of radon concentration measurements in the drinking water from the municipal water supply system and private wells located in the north-eastern part of Poland. The measurements were carried out on 643 samples using a liquid scintillation method. The mean value was found to be 5262 Bq m-3 with a maximum of 38347 Bq m-3. The samples were obtained from different water-bearing levels, i.e. surface water, deep borehole water and well water and have respective mean values of 3398, 5178 and 6155 Bq m-3. In 57 water samples, a guideline maximum level of 11,000 Bq m-3 was found to be exceeded. The observed radon concentration in water can contribute to a 2% increase in indoor radon concentration.

Heparin-induced modulation of insulin like-growth factor-I action on glucose level in control and fasted rats.

BACKGROUND: Insulin like-growth factor-I (IGF-I) circulates in serum bound to IGF-binding proteins (IGFBPs), which are important regulators of IGF's biological activity. There are at least two classes of BPs: a high molecular weight complex (HMWBPs) and low molecular weight species (LMWBPs), with different affinity for IGF-I. Their specific role in regulation of IGF-I bioactivity is still controversial. Since: a) IGF-I plays an important role in glucose counter regulation; b) heparin was shown to alter IGF-I affinity to BPs; and c) fasting is known to change quantity and quality of serum BPs, we decided to measure the in vivo effect of heparin on blood IGF-I, BPs and glucose levels in control and fasted rats. MATERIALS AND METHODS: Control and fasted rats were injected i.v. with heparin (500 UI/100 g body weight) every hour during 3 hours of the experiment. Blood samples were collected before and 15 or 30 minutes after heparin injection and used for determination of free and bound IGF-I (RIA), BPs (radiometric assay) and glucose level (glucose oxidase method). RESULTS: Heparin treatment induced hypoglycaemia in fasted rats while it induced hyperglycemia in control one. The evidence was provided that heparin dissociates IGF-I from HMWBPs complex of control rat serum (predominant one in serum of these animals) and released IGF-I in turn is bound to LMWBPs--known as inhibitors of IGF-I dependent functions. In contrast, in fasted rat serum heparin dissociates IGF-I from LMWBPs (predominant complex in serum of these animals) making IGF-I free and available to stimulate IGF-I dependent functions. Therefore in control animals, which were administered heparin, blood glucose level was elevated and in fasted animals it was decreased. CONCLUSIONS: The data presented raise the possibility that IGF-BPs may have an important role in IGF-dependent glucose counter regulation and that heparin or heparin-like molecules may affect the process. Medical significance of heparin-induced hyperglycaemia in control animals should be taken into consideration since heparin is commonly used in clinical practice.

[The measurement of radon in kindergarten and infant nursery buildings in East-North Poland]. / Pomiary stezenia radonu w budynkach przedszkoli i zlobków w regionie pólnocno-wschodniej Polski.

The measurements of radon concentration in 58 buildings of day nursery schools and kindergartens were performed in the six province of the East North Poland. The measurements of indoor radon were performed by means of a charcoal canister (Pico-Rad). The concentration ranged from 4.5 to 320 Bq/m3 and have arthimetic average 24.5 Bq/m3, geometric average 15.7 Bq/m3, median 15 Bq/m3. The highest average values were observed in Suwalki Province and Olsztyn Province. The results of all these measurements do not exceeded the limit of the Polish law.

Natural radioactivity of building components and materials used in Bialystok province.

The paper presents the results of the measurements of natural radioactivity of building components and materials used in the North-East part of Poland performed by the Department of Biophysics, Medical Academy of Bialystok. The natural radioactivity (40K, 224Ra and 232Th) of 133 samples was measured and the qualifying coefficients f1 and f2 were calculated. All measured samples of different materials had radioactivity level below legally accepted value. The lowest values of f1 and f2 were observed in prefabricated building materials; and they were lower then in traditional red brick. Only one sample of furnace slag had increased value of natural radioactivity, which was higher than legally permitted level.

Carbohydrate, protein and glycoprotein metabolism by the guinea-pig liver in chronic metribuzin poisoning.

Male guinea-pigs weighing 400-600 g, 8 months old, were given metribuzin directly into the gastric lumen over a period of 30 days (20 animals) or 90 days (20 animals) 6 times a week. In the liver of the poisoned animals, the glycogen level and the AspAT and AlAT activities, while in the serum the total protein and the fractions albumin, alpha 1-globulin and gamma-globulin significantly decreased; serum glucose and the serum fractions alpha 2-globulin and beta-globulin, each showed an increase. The glycogen level in the liver, total protein, glucose as well as the alpha 1 and alpha 2 globulin fractions in the serum showed not appreciable difference between 30 and 90 days of intoxication. After 90 days of metribuzin treatment AspAT and AlAT dropped in the liver and rose in the serum, in comparison to the 30-day values. As to the parameters of glycoprotein metabolism, the intoxicated animals showed a significant decrease and increase in concentration of hexosamines and sialic acids in the liver and serum, respectively. Metribuzin intoxication also cause a significant decrease in activity of glucosamine phosphate isomerase and significant increase in activity of glycosidases in the liver. The results suggest that metribuzin disturbs the metabolism of carbohydrates, proteins and glycoproteins in the guinea-pig liver.

[Stress-induced changes in the knee joint in men working in a kneeling position]. / Zmiany przeciazeniowe stawu rzepkowo-udowego u pracowników wykonujacych zawód w pozycji kleczacej.

Basing on clinical and radiological examinations as well as the perfusion of J125 iodoantipyrine in the patella it was found that 39% of paviors and 34.8% floorers exhibited changes resulting from overloading of that joint. Both groups revealed a high correlation between changes due to overloading and length of employment.

Analysis of curves Na-24 efflux from membrane labyrinth containing stria vascularis.

The efflux of Na-24 was investigated in isolated labyrinths from a membrane section containing stria vascularis and spiral ligament in artificial endolymph medium. The efflux curves were calculated and compartmental analyses were made. The theoretical possibility of a exchange of sodium between compartments connected in different ways was considered. The calculated values of rate constant of transmembranal sodium fluxes are 0.0282+/-0.0052 min-1 and the half-time of the exchange of sodium between intracellular compartments is 24.27+/-4.53 min. The distribution of sodium in tissue with a commonly applied simplification gives 90% Na+ in the extracellular compartment and 3% Na+ in the intracellular compartment of the total tissue sodium content. The possibility of measuring the rate constant of transmembranal electrolyte fluxes in this tissue seems encouraging for future investigation of the mechanism by which they are transported.

The effect of hypertonic urea solution on Na+ and K+ transport through the smooth muscle membrane.

The aim of this work was to examine the effect of a hypertonic solution (Krebs solution + 290 mM urea) on K+ and Na+ transport. The experiments were carried out on the guinea-pig taenia coli preparations using the method of Na-24 and K-24 loading and washout. The efflux curves were analysed by means of the digital computer technique. The following parameters were determined: efflux rate constant k2, influx rate constant k1, intracellular ion concentration C1 ion flux M and permeability P. Any significant difference between PNa/PK ratio in hypertonic urea and isotonic Krebs solutions was found.