Effect of He-Ne laser radiation on the chemiluminescence of mouse spleen cells

A study was made of He-Ne laser radiation (lambda = 632.8 nm) on spontaneous chemiluminescence of mouse splenic cells and that stimulated by addition of Candida albicans. Irradiation with low-intensity red light was shown to stimulate cell chemiluminescence and to intensify that stimulated by C. albicans within the dose range from 100 to 300 J/m2 with a maximum at about 200 J/m2.     

Increased susceptibility of activated rat liver chromatin to DNAse I

Rat liver chromatin activated by partial hepatectomy is more susceptible to the action of DNAse I than control chromatin isolated from intact liver. The study on the transfer of chromatin material to the acid-soluble fraction reveals a higher rate of activated chromatin degradation. Activated chromatin shows also an increased capacity for ethidium bromide (EB) binding as estimated from the isotherms of adsorption. The difference in EB binding between activated and control chromatin is abolished after DNAse I treatment. Conditions of mild digestion with DNAse I have been found under which the number of binding sites for EB per nucleotide decreases to almost the same level in activated and non-activated chromatin. The results suggest a preferential degradation of those DNA sequences in activated chromatin that are responsible for the increase in the ligand binding.     

The 1st results in the realization of the Harm Reduction program for intravenous narcotic users in the city of Penza

To achieve the aims of the project, the following stages were consecutively defined: (1) the exchange of syringes, organized by outreach workers, with the simultaneous popularization of the project, (2) the orientation of intravenous drug users to attending syringe exchange stations and (3) the extension of the area covered by the activities of outreach workers. Our experience showed that outreach workers, especially those working in the street, were the main force to count on for achieving success in the work of the projects. The budget of the project should provide for the publication of information material. Special assignments for outreach workers to study some concrete problem (drug service, the use of blood, etc.) can be useful. It is expedient to raise the status of syringe exchange stations by turning them into multi-purpose consultation centers.     

Analysis of plastid DNA-like sequences within the nuclear genomes of higher plants

A wide-ranging examination of plastid (pt)DNA sequence homologies within higher plant nuclear genomes (promiscuous DNA) was undertaken. Digestion with methylation-sensitive restriction enzymes and Southern analysis was used to distinguish plastid and nuclear DNA in order to assess the extent of variability of promiscuous sequences within and between plant species. Some species, such as Gossypium hirsutum (cotton), Nicotiana tabacum (tobacco), and Chenopodium quinoa, showed homogenity of these sequences, while intraspecific sequence variation was observed among different cultivars of Pisum sativum (pea), Hordeum vulgare (barley), and Triticum aestivum (wheat). Hypervariability of plastid sequence homologies was identified in the nuclear genomes of Spinacea oleracea (spinach) and Beta vulgaris (beet), in which individual plants were shown to possess a unique spectrum of nuclear sequences with ptDNA homology. This hypervariability apparently extended to somatic variation in B. vulgaris. No sequences with ptDNA homology were identified by this method in the nuclear genome of Arabidopsis thaliana.      

Incidence and levels of fumonisin contamination in Colombian corn and corn products

A survey was conducted to determine the levels of fumonisins B1 and B2 in corn and corn-based products available in Colombia for human and animal consumption. A total of 120 samples were analyzed by acetonitrile-water extraction, cleanup with a strong-anion-exchange column, and liquid chromatography with o-phthaldialdehyde-2-mercaptoethanol derivatization and fluorescence detection. The samples of corn and corn-based products for animal intake were taken at different feed manufacturing plants, whereas the samples used for human foods where purchased from local retail stores. The number of positive samples for fumonisin B1 was 20.0% higher in corn and corn-based products for animal intake (75.0%) than in corn and corn-based products for human consumption (55.0%). The levels of fumonisin B1 were also higher in corn and corn-based products for animal intake (mean = 694 μg/kg; range = 32–2964 μg/kg), than in corn and corn-based products for human intake (mean = 218 μg/kg; range = 24–2170 μg/ kg). The incidence and levels of fumonisin B2 were lower than those for fumonisin B1. Corn and corn-based products for animal consumption had an incidence of fumonisin B2 of 58.3%, with a mean value of 283 μg/kg, and a range of 44–987 μg/kg. The incidence of fumonisin B2 in corn-based products for human intake was 35.0%, with a mean value of 118 μg/kg and a range of 21–833 μg/kg. The highest incidence and levels of fumonisins were found in samples of hominy feed, with concentrations ranging from 86 to 2964 μg/kg fumonisin B1 and 57 to 987 μg/kg fumonisin B2.     

A technological approach to the description of group foraging in the ant <Emphasis Type="Italic">Myrmica rubra</Emphasis>

Group foraging in Myrmica rubra ants is considered as a cyclic process in which transition from one phase to another is determined by summation of actions of individual ants inside the nest and in the foraging territory. In its turn, individual behavior is considered as a labile sequence of tasks, such as territory exploration, acquiring and transportation of food, the completeness of the sequence depending on the individual experience. Data on foraging of three experimental M. rubra colonies were represented as a relational database in MS Access 2007, and the database tools were used to study the interrelated characteristics of the two levels of the foraging process (group and individual) and to analyze the quantitative parameters of individual and group behavior.