Lipopolysaccharide-induced necrosis of grafted tumors was potentiated by several hydrophilic and lipophilic muramyl dipeptide (MDP) derivatives administered a few hours prior to small amounts of lipopolysaccharide (LPS) in spite of low titers of induced circulating tumor necrosis factor (TNF). However, pretreatment with MDP derivatives did increase the level of TNF in the blood of mice challenged by a greater dose of LPS. The TNF amount in 2 h postendotoxin mouse serum reached a peak when the glycopeptide had been given 6 h before the challenge, being approximately 100-fold above that obtained in unprimed mice. The cytotoxic activity in mouse serum was inhibited by rabbit antibodies raised against recombinant mouse TNF. Although there exists a toxic synergism between BCG or MDP and endotoxin, the effect of certain MDP derivatives was not related to an increased susceptibility to the toxicity of LPS.

No abstract

Chromosomal studies in peripheral lymphocytes from 63 residents near the Semipalatinsk nuclear test site, at ages of 52-63 years old, were performed in 2001-2002. A higher rate of chromosome aberrations was observed in the two contaminated villages, Dolon and Sarjal, compared with the control village, Kokpekti. Moreover, a relationship of frequency of cells with radiation induced chromosome aberrations and the previously estimated exposure dose was observed. Furthermore, apparent nuclear abnormalities (ANA) of thyroid follicular cells were studied in 30 out of 63 residents, who were examined for chromosome aberrations. A higher rate of ANA was also found in the residents in the exposed villages compared with those in the control village. These results suggest radiation effects both on the chromosomes in peripheral lymphocytes and on the follicular cells in the thyroid.

The Republic of Kazakhstan has one of the world’s highest suicide rates. A detailed study of the risk factors for suicide in that country is therefore important. We investigated country-wide statistics related to labor, financial, and economic factors and whether any of these factors contribute to the risk of suicide in Kazakhstan. Using the 20 year period from 2000 to 2019, we examined the annual suicide rates overall (all citizens) and for males and females in Kazakhstan, annual unemployment rates, annual rates of increase in the country’s consumer price index, annual total exports, and annual total imports. We then calculated the correlations between the suicide rates and these four items. We also performed a multiple regression analysis of the relationship between the suicide rate and those four items. The results of these analyses indicated that the unemployment rate was the correlation coefficient most highly correlated with the suicide rate; unemployment was significantly related to suicide and should be targeted as a risk factor in suicide prevention interventions in Kazakhstan. With this in mind, organizations, government agencies, and professionals in relevant fields need to devise and implement suicide prevention measures.