Five complementing recessive mutations that exhibit increased bacterial transposon Tn5 precise excision in yeast Saccharomyces cerevisiae were obtained by ethylmethanesulfonate treatment. One of these mutations (tex1) was submitted to extensive genetic analysis. tex1 is a recessive temperature-sensitive mutation resulting in a 20-100-fold increase in Tn5 excision. It also has increased frequencies of ochre mutation reversion, of forward mutation to canavanine resistance, and loss of chromosome III or its right arm. The possible mechanism of tex1 effects is discussed.

Background: Human aggression is a heterogeneous behavior with biological, psychological, and social backgrounds. As the biological mechanisms that regulate aggression are components of both reward-seeking and adversity-fleeing behavior, these phenomena are difficult to disentangle into separate neurochemical processes. Nevertheless, evidence exists linking some forms of aggression to aberrant serotonergic neurotransmission. We determined possible associations between 6 serotonergic neurotransmission-related gene variants and severe criminal offenses. Methods: Male Russian prisoners who were convicted for murder (n = 117) or theft (n = 77) were genotyped for variants of the serotonin transporter (5HTTLPR), tryptophan hydroxylase, tryptophan-2,3-dioxygenase, or type 2C (5-HT2C) receptor genes and compared with general-population male controls (n = 161). Prisoners were psychologically phenotyped using the Buss-Durkee Hostility Inventory and the Beck Depression Inventory. Results: No differences were found between murderers and thieves either concerning genotypes or concerning psychological measures. Comparison of polymorphism distribution between groups of prisoners and controls revealed highly significant associations of 5HTTLPR and 5-HTR2C (rs6318) gene polymorphisms with being convicted for criminal behavior. Conclusions: The lack of biological differences between the 2 groups of prisoners indicates that the studied 5HT-related genes do not differentiate between the types of crimes committed.

We have demonstrated that precise excision of bacterial transposon Tn5 can occur in the yeast, Saccharomyces cerevisiae. Tn5 insertions in the yeast gene LYS2 were generated by transposon mutagenesis made in Escherichia coli by means of a lambda::Tn5 vector. Nine insertions of Tn5 into the structural part of the yeast LYS2 gene situated in a shuttle episomal plasmid were selected. All the plasmids with a Tn5 insertion were used to transform yeast strains carrying a deletion of the entire LYS2 gene or a deletion of the part of LYS2 overlapping the point of insertion. All insertions inactivated the LYS2 gene and were able to revert with low (about 10(-8) frequencies to lysine prototrophy. Restriction analysis of revertant plasmids revealed them to be indistinguishable from the original plasmid without Tn5 insertion. DNA sequencing of the regions containing the points of insertions, made for two revertants, proved that Tn5 excision was completely precise.

We studied blood serum levels of neurosteroids, dehydroepiandrosterone and its sulfate, in individuals with personality disorders convicted of serious violent crimes. The data were compared with that of a group of mentally and physically healthy persons convicted of acquisitive crimes, and with that of the control group. Significant increase in DHEA in both groups of convicts in comparison with the control was shown. The level of dehydroepiandrosterone sulfate remained unchanged. Increased dehydroepiandrosterone level in the convicted individuals with personality disorders is probably more associated with detention stress than directly with psychopathology or criminal aggression.

An in-depth analysis conducted on the historical background and current status of occupational medicine in Russia is presented. Scientific and practical bases of occupational medicine in the Russian Federation were based on 2 of the most important principles of health service: free medical care and its preventive orientation. Our analysis of the current situation in occupational medicine in modern Russia shows a transition from the vision of zero occupation-related harm to the strategy of recognizing, assessing, and managing occupational exposures. The system of workplace monitoring is developing successfully, with the creation of a federal database for the state of working conditions and the implementation of mechanisms for occupational risk assessment and management. However, at the same time, the system of medical surveillance for workers needs substantial reform. Over the past few years, the professional community of specialists in occupational medicine has taken several steps to improve the quality of its work. Understanding of the need for reforming the system of occupational medicine has continued to grow, which will improve the quality of medical monitoring for workers and extend professional longevity. Current challenges and prospects of occupational medicine in the Russian Federation are discussed.