Changes in the cytokine profile and reduced function of lymphocyte subpopulations in subacute tetrachloromethane poisoning.

Experiments on outbred albino rats showed that subacute poisoning with tetrachloromethane in a total dose of 1.0 LD50 appreciably decreased blood concentrations of cytokines (IFN-gamma, IL-2, IL-4, IL-6, IL-10), reduced the IFN-gamma/IL-4 ratio in comparison with the control, and suppressed the immune reactions, which attests to greater damage to Th1 compared to Th2 lymphocytes.

[The first proof of a possibility of change of temperature norms of insect development as a result of artificial selection for rapid or slow development by the example of the red soldier bug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)].

For 3-4 generations, selection of the most rapidly and slowly developing nymphs at 28 degrees C was performed on four families of the red soldier bug Pyrrhocoris apterus L. In each generation, duration of development of nymphs was determined at 5 constant temperatures from 20 degrees C to 28 degrees C. From these data there were calculated the linear regression coefficient of the development rate for temperature (the coefficient of the thermolability of development) and the temperature development threshold for each generation. As a result of the selection the mean duration of the nymph development was shortened or increased statistically significantly depending on its direction. The artificial selection for the development duration has been established to change not only this parameter, but also the temperature norms of the insect development. At selection for rapid development the regression line scope (i. e., the regression coefficient value) increased statistically significantly, i. e., development became more dependent on temperature. The temperature threshold of development increased. At selection for slow development the values of the regression coefficient and of the threshold decrease, but these differences were not statistically significant. The effect of artificial selection for duration of development on temperature norms of insect development has been revealed for the first time.

[Study of intrapopulation variability of duration and thermal norms of development of the linden bug Pyrrhocoris apterus (Heteroptera, Pyrrhocoridae)].

The existence of significant variability in duration and temperature norms of development has been shown for the first time between families within insect populations. This variability is infer-family and therefore has genetic basis. Revealed for the first time is the statistically significant positive correlations between the regression coefficient of the rate of development for temperature and the threshold of temperature for development of eggs and larvae from different families. The greater the slope of the regression line of the development rate for temperature, the higher the temperature threshold value in this particular family. These results demonstrate for the first time existence of genetic covariation between the regression coefficient and the temperature threshold within the insect populations. It is suggested that the intrapopulational genetic variability in the development time, regression coefficient, and the temperature threshold for development, which is the subject of natural selection, might be the source of the interpopulation and interspecies variability of the temperature reaction norms of development. It was found that value of the linear regression coefficient of development rates for temperature were statistically significantly higher, while the temperature threshold values--lower in eggs as compared with the corresponding parameters in larvae. These results obviously are in contradiction with the concept of the "developmental rate isomorphy in insects and mites" (Jarosik et al., 2002) which claims that the temperature threshold for development should be the same for all species cycle stages, so that only slopes of the regression lines can differ. Shown for the first time was the absence of genetic co-variability of the temperature reaction norms for development of different life cycle stages, i. e., eggs and larvae. This means that the regression coefficient (as well as the temperature requirement of the sum of the degree-days) and the temperature threshold for development in eggs and larvae are inherited independently and thereby they can change in evolution independently according to specific environmental condition under which these life cycle stages exist.

[Changes in the toxicity and immunotoxity of tetrachloromethane and carbophos under the action of 2,4,6-triphenyl-4H-selenopyran and their connection with cytochrome P-450 dependent monooxygenase system].

It is established in experiments on noninbred rats that 2,4,6-triphenyl-4H-selenopyrane (peroral administration in a dose of 0.8 mg/kg during 3 days) induces cytochrome P450, thus increasing the toxicity and immunotoxicity of carbon tetrachloride (metabolized via "lethal synthesis"), and reduces the analogous effects of carbophos, the biotransformation of which proceeds via the formation of low-toxicity and nontoxic metabolites.

[Degradation of p-toluenesulfonate by immobilized Comamonas testosteroni BS1310 (pBS1010) cells].

Parameters of degradation of p-toluenesulfonate (TS) by free and agar-embedded Comamonas testosteroni BS1310 (pBS1010) cells were determined. The maximum rate of TS degradation was 25% lower in by immobilized than free cells, equaling 11 nmol x min(-1) x mg(-1) cells. Degradation of TS by both free and immobilized cells was associated with molecular oxygen consumption (molar ratio, 1 : 2). In a plug-flow reactor, the degradation rate was 10.4 nmol x min(-1) x mg(-1) cells. The results can be applied to designing reactors for TS degradation in sewage and developing biosensors.