Experience of thyroid gland status screening in postchernobyl period.

The main results of thirty-year period of repeated screening programs and observational studies in contaminated and non-contaminated regions of Belarus are analyzed. The possible reasons of discrepant and contradictory data about the consequences of Chernobyl catastrophe delivered by different study groups during early period after the accident are discussed. High incidence of thyroid nodular disease and cancer in children and adolescence after the catastrophe are described. The research shows high effectiveness of screening in early diagnosis thyroid disorders and radiation-induced thyroid cancer in different regions of Belarus and in various time points.

Influence of nitrate in drinking water on the prevalence of thyroid cancer and other diseases (literature review and experience in post-chernobyl period in Belarus).

In the last 60 years dramatically increased the content of nitrates in groundwater due to intensive use of nitrogen fertilizers in agriculture. Research in post-Chernobyl period has shown that a sharp increase in the incidence of thyroid cancer depends not only on the level of thyroid dose, but also on the level of nitrates in groundwater.

[The characteristics of long-term dentate tetanus of the skeletal muscle in the rat after cold adaptation]. / Kharakteristika dlitel'nogo zubchatogo tetanusa skeletnoi myshtsy krysy posle adaptatsii k kholodu.

Prolonged unfused tetanuses of control and cold-adapted rats' m. gastrocnemius at different muscle temperature (29-30 and 24-25 degrees C) were studied. The time of achievement of the maximum level increased, the phase of higher thermogenesis became longer and the third economic phase was delayed after cold adaptation (both at 29-30 degrees C and 24-25 degrees C).

[The effect of cooling on the characteristics of a single skeletal muscle contraction in cold-adapted rats]. / Vliianie okhlazhdeniia na kharakteristiku odinochnogo sokrashcheniia skeletnoi myshtsy u adaptirovannykh k kholodu krys.

The time parameters and amplitude of the m. gastrocnemius twitch contractions were studied in control and in cold-adapted rats at optimal muscle temperature (29-30 degrees C) and after cooling the muscle to 24-25 degrees C. A decrease of the twitch contraction force and an increase of the time of the contraction to the maximum, occurred in cold-adapted rats. The cooling of muscle decreased the velocity of the twitch contraction in both groups of animals.

[Contractile responses of subcutaneous vessels to drops in temperature]. / Kontraktil' nye reaktsii podkozhnykh sosudov na perepady temperatury.

In rabbits, application of ice-cold water to the ear lowers the skin temperature by 10.3 degrees C and, within 3-4 sec, the temperature in the subcutaneous vein by 4.3 degrees C. A stepwise cooling of isolated subcutaneous artery or vein causes their constriction, and warming dilates the vessels with maximal amplitude when the temperature is changed by 8-12 degrees C. Further cooling or warming diminishes the response. Optimal constrictory responses of subcutaneous vessels to a standard dose of norepinephrine were observed at 38-32 degrees C.

[Impulse activity of skin receptors in local convective and radiant cooling]. / Impul'snaia aktivnost' kozhnykh retseptorov pri konvektivnom i radiatsionnom lokal'nom okhlazhdenii.

In rabbits, impulse activity in cooling through convection was 8 times as great as in cooling through radiation. The former cooling increases impulse activity twofold as compared to the radiation cooling in hairless areas. Changes in impulse activity of fibers of the cutaneous nerve were characterized by considerable fluctuations of rhythm and an increase of receptors activity in hairless areas thus showing an obvious relation with cooling of cutaneous tissues.

[Characteristics of lengthy spiked tetanus of rat skeletal muscle]. / Kharakteristika dlitel'nogo zubchatogo tetanusa skeletnoi myshtsy krysy.

Prolonged unfused tetanuses of the rat m. gastrocnemius were investigated. An increase in the stimulation frequency raised the tension of unfused tetanuses, shortened the time of achievement of the maximum level, and accelerated the beginning of the third (economic) phase. After cooling the muscle to 24-25 degrees C, the unfused tetanuses developed yet during low frequency stimulation and the economic phase began sooner.

[Thermoregulatory response to local convection and radiation cooling]. / Reaktsii termoreguliatsii na lokal'noe konvektivnoe i radiatsionnoe okhlazhdenie.

When equal amounts of cooling were applied to the skin of rabbits the heat production and heat loss elicited by means of convection had shorter latencies and were by 40 to 50 per cent more pronounced that those elicited by radiation. The correlation of the thermoregulatory reactions with the skin temperature was more stable in experiments with convective cooling. Cooling of the skin by 7 to 10 degrees C was optimal for the distinctions between the results.

[Analysis of reflex thermoregulatory reactions induced by thermal stimulation of the trigeminal zone]. / Analiz reflektornykh reaktsii termoreguliatsii, vyzyvaemykh termicheskim razdrazheniem trigeminal'noi zony.

In anesthetized rabbits, the activity of thermoreceptors, the neuronal activity in the preoptic area of hypothalamus (POAH), and the efferent outflow in sympathetic fibres of the auricular nerve were studied during thermal stimulation of the skin innervated by the trigeminal nerve. Among 79 receptors 8 responded to warming of the skin and 38 responded to cooling with the maximal activity at the skin temperature 22-21 degrees C. The activity of 46 POAH neurons out of 94 correlated with the skin temperature: 34 neurons increased the frequency of firing during cooling and 12 during warming. The firing rate in the sympathetic ganglion cells and postganglionic fibers increased by 50-100% during cooling causing vasoconstriction of the rabbit's ear, while warming of the receptive zone reduced the activity by 56-48% or abolished it, leading to vasodilatation.

[Radioiodine therapy for benign thyroid diseases].

There are 3 alternative methods of treating benign thyroid diseases that occur with thyrotoxicosis syndrome: medication, surgery, and radioiodine therapy. However, there are some features in the approaches to the treatment of autoimmune and non-immune hyperthyroidism.

[Triiodothyronine reception after exposure to low doses of ionizing radiation]. / Sostoianie retseptsii triiodtironina pri deistvii ioniziruiushchego izlucheniia v malykh dozakh.

Effects of ionizing radiation in doses 0.5 and 1 Gy on triiodothyronin reception by rat peripheral blood lymphocytes were examined 3, 10, and 30 days after exposure. Binding capacity of 125-I labeled triiodothyronin by lymphocyte receptors was found to change depending on the dose of external irradiation and time elapsed since the exposure. The most marked and earliest changes in the parameters of hormonal-receptor interaction were observed after irradiation in dose 1 Gy.

[Features of triiodothyronine reception in incorporation of radioactive iodine]. / Osobennosti retseptsii triiodtironina pri inkorporatsii radioaktivnogo ioda.

Effects of incorporated 131I in combination with intake of fodder contaminated with 134,137Cs on triiodothyronin reception by peripheral blood lymphocytes in rats aged 2 and 6 months were examined. Incorporation of 131I was found to cause specific binding of the hormone, particularly marked in young animals.