Comparative effectiveness of antioxidant melatonin and radioprotectors indralin and phenylephrine in local radiation injuries

In experiments on mice radioprotective properties of indraline, phenyleprine and melatonin were compared at topical application as an ointment at a place of local exposure of animal hind to a dose of 38.3 Gy of 60Co gamma-quanta. Factor of dose reduction was 1.27-1.32 for indraline (1-10% ointment) and 1.29 for phenyleprine (0.25% ointment). Antioxidants were low efficient at radiation skin burn. At later local radiation injuries, such as hind contracture, the efficiency of indraline was 1.33-1.5, that of phenyleprine was 1.28, and that of melatonine (2 and 5% ointment) was 1.23-1.47.     

Influence of changes in glutathione concentration on body temperature and tolerance to cerebral ischemia

Two compounds that deplete glutathione (buthionine sulfoximine and diethyl maleate) with different mechanisms of action decrease body temperature and increase tolerance to complete global cerebral ischemia, both correlating closely with the glutathione concentration decrease. Glutathione apparently participates in the regulations of these functional parameters. GSH diethyl ester does not influence the latter, though it increases moderately the GSH concentration. Injection of GSH ester into the cerebral ventricles or subcutaneously selectively increases the GSH level in the brain and liver. An influence of the brain on the glutathione system in the liver was revealed. Diethyl maleate and GSH ester increase the activity of glutathione metabolizing enzymes under certain conditions.     

Clinical strains of Burkholderia cepacia: characteristic and detection of the components in the quorum sensing regulatory system

Described in the paper are characteristics of B. cepacia clinical strains isolated from patients at Moscow hospitals. The strains were investigated for the presence of proteolytic, chitinolytic, hemolytic and lipase activities as well as for presence of components of the "Quorum sensing" gene activity regulatory system by using biological test-systems and in the polymerase chain reaction with primers to genes cepI and cepR.     

Fumonisin B1-induced cell death in arabidopsis protoplasts requires jasmonate-, ethylene-, and salicylate-dependent signaling pathways

We have established an Arabidopsis protoplast model system to study plant cell death signaling. The fungal toxin fumonisin B1 (FB1) induces apoptosis-like programmed cell death (PCD) in wild-type protoplasts. FB1, however, only marginally affects the viability of protoplasts isolated from transgenic NahG plants, in which salicylic acid (SA) is metabolically degraded; from pad4-1 mutant plants, in which an SA amplification mechanism is thought to be impaired; or from jar1-1 or etr1-1 mutant plants, which are insensitive to jasmonate (JA) or ethylene (ET), respectively. FB1 susceptibility of wild-type protoplasts decreases in the dark, as does the cellular content of phenylalanine ammonia-lyase, a light-inducible enzyme involved in SA biosynthesis. Interestingly, however, FB1-induced PCD does not require the SA signal transmitter NPR1, given that npr1-1 protoplasts display wild-type FB1 susceptibility. Arabidopsis cpr1-1, cpr6-1, and acd2-2 protoplasts, in which the SA signaling pathway is constitutively activated, exhibit increased susceptibility to FB1. The cpr6-1 and acd2-2 mutants also constitutively express the JA and ET signaling pathways, but only the acd2-2 protoplasts undergo PCD in the absence of FB1. These results demonstrate that FB1 killing of Arabidopsis is light dependent and requires SA-, JA-, and ET-mediated signaling pathways as well as one or more unidentified factors activated by FB1 and the acd2-2 mutation.     

Tracking the pathway of calcium phosphate/DNA nanoparticles during cell transfection by incorporation of red-fluorescing tetramethylrhodamine isothiocyanate–bovine serum albumin into these nanoparticles

Calcium phosphate nanoparticles were prepared by precipitation from water and were then functionalized by DNA. These particles are taken up by living cells and function as gene transfer agents, i.e., the DNA is brought into a cell’s nucleus and is incorporated there into the cell’s genome (transfection). DNA which encodes for enhanced green fluorescent protein leads to green fluorescence of successfully transfected cells. By adding the red-fluorescing marker tetramethylrhodamine isothiocyanate–bovine serum albumin (TRITC-BSA) to the nanoparticles, their pathway into the cell and within the cell could be followed by fluorescence microscopy. A clear correlation between the uptake of nanoparticles and the efficiency of transfection was found. Aggregates of DNA/TRITC-BSA alone were not able to enter the cells, i.e., the inorganic nanoparticles are necessary as a carrier through the cell membrane.