EFFECT OF 2,6-DIMETHYLPYRIDINE-N-OXIDE ON THE SEVERITY OF CYTOGENETIC EFFECTS INDUCED BY DIOXIDINE IN BONE MARROW CELLS OF MICE.

Objective - to study the ability of 2,6-dimethylpyridine-N-oxide to modify the cytogenetic effects in mouse bone marrow cells caused by the pro-oxidant mutagen Dioxidine. The cytogenetic activity and mutagen-modifying effect of the plant growth regulator 2,6-dimethylpyridine-N-oxide (Ivin) were studied by the method of accounting for chromosomal aberrations in the bone marrow cells of CD-1 mice (males) with a single joint exposure with Dioxidine. Ivin was administered single orally in the form of an aqueous solution at doses of 710, 71, and 0.7 mg/kg bw, which corresponds to 1/2, 1/20, 1/2000 of LD50 after intraperitoneally administered of Dioxidine at a dose 100 mg/kg. The animals of the positive control group were treated Dioxidine intraperitoneally at a dose of 100 mg/kg bw. Intact animals (negative control group) were orally administered purified, UV-sterilized, deionized water. It was shown that when combined with Dioxidine, Ivin at doses of 710, 71, and 0,7 mg/kg bw significally reduced the frequency of metaphases chromosome aberrations, relative to positive control by 55,56%, 66,70%, and 74,08% respectively. No multi-aberrant and polyploid cells were observed. In all variants of the experiment, only chromatid-type chromosome aberrations with single fragments were detected in the spectrum of chromosome aberrations. The severity of this effect had an inverse dose dependence: with a decrease in the dose of Ivin, the cytogenetic effects of Dioxidine decreased to a greater extent than with high doses of Ivin. The high antimutagenic effect of Ivin was confirmed, which is expressed to a greater extent when it is combined with Dioxidine than with Cyclophosphamide. These findings may be associated with the genoprotective effect of Ivin, due to the stabilization of membranes and its antioxidant effect.

[; INFLUENCE OF N-OXIDE-2,6-DIMETHYLPYRIDINE ON THE EXPRESSION OF CYTOGENETIC EFFECTS INDUCED BY CYCLOPHOSPHAMIDE IN MOUSE BONE MARROW CELL].

Objective - to study the ability of N-oxide-2,6-dimethylpyridine to modify the cytogenetic effects in mouse bone marrow cells caused by an alkylating antitumor cytostatic cyclophosphamide.; The cytogenetic activity and mutagen-modifying effect of the plant growth regulator N-oxide-2,6-dimethylpyridine (Ivin) were studied by the method of accounting for chromosomal aberrations in the bone marrow cells of CD-1 mice (males) with a single joint exposure to cyclophosphamide. In the first variant of the research, Ivin was administered single orally in the form of an aqueous solution at doses of 710, 71, 7.1, 0.7, and 0.07 mg/kg bw, which corresponds to 1/2, 1/20, 1/200, 1/2000 and 1/20000 from LD50. In the second variant - Ivin was administered together with Cyclophosphamide (Ivin - in the same way as in the first research variant, cyclophosphamide was administered intraperitoneally at a dose of 40 mg/kg bw the same as the positive control group). Intact animals (negative control group) were orally administered purified, UV-sterilized, deionized water.; It was shown that with isolated administration of Ivin in the studied doses did not show mutagenic activity. When combined with Cyclophosphamide, Ivin at a dose of 710 mg/kg bw did not induce the frequency of metaphases with chromosome aberrations and at a dose of 71 mg/kg bw reduced the frequency of metaphases with chromosome aberrations by 1.8 times in comparison with the positive control. In both of these dose groups, Ivin reduced the number of chromatid-type aberrations and polyploid cells but increased the number of multi-aberrant cells. This is probably due to the additional chemical load and physicochemical state of the Ivin molecule. When combined with Cyclophosphamide, Ivin at low dose levels (7.1, 0.7 and 0.07 mg/kg bw) significantly reduced the frequency of metaphases with chromosome aberrations (by 55.7%, 62.9% и 72.9%, respectively), the amount of chromatid-type aberrations, polyploid, and multi-aberrant cells. This may be due to the gene protective effect of Ivin, because of the stabilization of membranes and its antioxidant effect.

Effects of electromagnetic fields emitted by GSM phones on working memory: a meta-analysis.

BACKGROUND AND OBJECTIVE: Current treatments for Alzheimer's Disease (AD) do not affect the course of the illness and brain stimulation techniques are increasingly promoted as potential therapeutic interventions for AD. This study reviews the effects of electromagnetic field (EMF) exposure versus sham exposure on working memory (WM) performance of healthy human participants. METHOD: Online literature databases and previous systematic reviews were searched for studies of EMF and WM in participants without reported memory problems. Two thousand eight hundred and fifty seven studies were identified, and 10 studies met the inclusion criteria. An assessment of study quality was completed, and separate, random effects meta-analyses were conducted for each of the three WM tasks included: n-back, substitution and digit span forward. RESULTS: No differences were found between participants exposed to active EMF versus sham conditions in any of the three working memory tasks examined. CONCLUSION: Results indicate that EMF does not affect WM during the n-back, substitution and digit-span tasks. Future studies should focus on the possible effects of chronic exposure to EMF in older adults with AD using a battery of comparable WM and attention tasks, before EMF can be seriously considered as a potential modulator of WM in AD. Copyright © 2016 John Wiley & Sons, Ltd.

Methodological approaches for producing doubled haploids in sugar beet and red beet (Beta vulgaris L.).

The in vitro production of doubled haploids is a biotechnological path of an accelerated development of parental lines in F1-hybrid breeding programs. Unlike the traditional inbreeding method requiring 5 to 6 generations to reach a suf-f icient homozygosity of lines, the number of generations to produce pure lines of beet by haploid technologies is reduced to 2. The production of doubled haploids by gynogenesis is the most common biotechnological approach in sugar and red beets. Protocols for the production of doubled haploids for B. vulgaris species are few and have been developed mainly for sugar beets. There are no protocols for the production of doubled haploids for red beet (B. vulgaris convar. esculenta Salisb.), and the protocols developed for sugar beet (B. vulgaris convar. saccharifera Alef.) are ineffective for red beet, even though these two crops belong to the same species. The greatest success has been achieved in the production of doubled haploids by gynogenesis through isolated ovule culture, especially in sugar beet. Studies on the production of doubled haploids by androgenesis were actively carried out in the 1970s and 1980s and did not lead to the production of regenerated plants. However, at present, there is renewed interest among researchers in this approach, and scientists in different countries are conducting studies of Beta vulgaris androgenesis through isolated microspore culture. This article provides an overview of studies devoted to the production of doubled haploids, addressing the main problems of doubled haploid technologies, and methods to increase the frequency of embryogenesis and doubled haploid plant formation in B. vulgaris crops.