Interrelation of cerebral vessels reactivity and state of central afferent inductive structures at chronic mercury intoxication

The following groups were examined under clinical condition: the 1st group (47 persons) - the employees with a long work period working at the Joint-Stock Company "Sayanskchimplast" exposed to mercury compound. The mean age - 49,2 ± 4,4 years old, the mean working period -18,1 ± 5,6 years. The 2nd group (51 persons) consisted of the employees working at the Joint-Stock Company "Usolyechimprom" in Irkutsk Region with the diagnosis of chronic mercury intoxication (CMI), the mean age - 42,7 ± 4,3 years old and the mean time period of exposure to mercury - 12,3 ± 2,7 years. The postcontact period amounted 8,5 ± 2,6 years. The examination data of 26 persons (males) who were not exposed to the harmful production factors were used as the control one. All the persons examined were subjected to the ultrasonic dopplerography of the extracranial vessels and the registration of the somatosensoric induced potentials. This study allowed to assess the state of the cerebral hemodinamics manifested as the autoregulation disorder of the brain bloodflow along the metabolic contour in the employees examined in both groups. It should be noted the presence of the change correlation in the state of the central afferent inductive structures consisting in growing the time period of the central conductive capability, that is, the conductance from the lower sections of the stem up to the brain cortex and the functional change in the metabolic diameter regulation of the cerebral vessels in the patients exposed to the metallic mercury at the production. As compared with the control the more expressed index change of the somatosensoric induced potentials were registered in the subgroup of the patients in the postponed period of chronic mercury intoxication with the revealed regulation disorders of the cerebral vessels. The change were found to correlate with the impulse conductance disorders at the level of the thalamic and cortical structures. The attention should be paid that the change revealed were registered in the group of the patients exposed to the metallic mercury at the production but without the revealed diagnosis of chronic mercury intoxication with allow to consider the presence of the changes in the state of the conductive structures in this group of the patients examined

Protein-DNA crosslinking in reconstituted nucleohistone, nuclei and whole cells by picosecond UV laser irradiation.

A picosecond UV laser was used to cross-link proteins to DNA in nuclei, whole cells and reconstituted nucleohistone. Irradiation of the nucleohistone resulted in crosslinking 15-20% of bound histones to DNA in a very short time (one or several picosecond pulses), the efficiency of crosslinking to single stranded DNA being higher than to double stranded DNA. All histones as well as high mobility group 1 proteins were identified in the covalently linked protein-DNA complexes upon irradiation of isolated nuclei and whole cells. A method is suggested for isolation of crosslinked material from cells and nuclei in amounts sufficient for further analysis. Experiments with reconstituted nucleohistones showed that upon irradiation at a constant dose the efficiency of crosslinking depended on the intensity of the light, thus suggesting a two-quantum process is involved in the reaction

Multiple Roles of Alu-Related Noncoding RNAs

Repetitive Alu and Alu-related elements are present in primates, tree shrews (Scandentia), and rodents and have expanded to 1.3 million copies in the human genome by nonautonomous retrotransposition. Pol III transcription from these elements occurs at low levels under normal conditions but increases transiently after stress, indicating a function of Alu RNAs in cellular stress response. Alu RNAs assemble with cellular proteins into ribonucleoprotein complexes and can be processed into the smaller scAlu RNAs. Alu and Alu-related RNAs play a role in regulating transcription and translation. They provide a source for the biogenesis of miRNAs and, embedded into mRNAs, can be targeted by miRNAs. When present as inverted repeats in mRNAs, they become substrates of the editing enzymes, and their modification causes the nuclear retention of these mRNAs. Certain Alu elements evolved into unique transcription units with specific expression profiles producing RNAs with highly specific cellular functions