Some problems and errors in cytogenetic biodosimetry

Human radiosensitivity is a quantitative trait that is generally subject to binomial distribution. Individual radiosensitivity, however, may deviate significantly from the mean (by 2-3 standard deviations). Thus, the same dose of radiation may result in different levels of genotoxic damage (commonly measured as chromosome aberration rates) in different individuals. There is significant genetic component in individual radiosensitivity. It is related to carriership of variant alleles of various single-nucleotide polymorphisms (most of these in genes coding for proteins functioning in DNA damage identification and repair); carriership of different number of alleles producing cumulative effects; amplification of gene copies coding for proteins responsible for radioresistance, mobile genetic elements, and others. Among the other factors influencing individual radioresistance are: radioadaptive response; bystander effect; levels of endogenous substances with radioprotective and antimutagenic properties and environmental factors such as lifestyle and diet, physical activity, psychoemotional state, hormonal state, certain drugs, infections and others. These factors may have radioprotective or sensibilising effects. Apparently, there are too many factors that may significantly modulate the biological effects of ionising radiation. Thus, conventional methodologies for biodosimetry (specifically, cytogenetic methods) may produce significant errors if personal traits that may affect radioresistance are not accounted for

Efficient Synthesis of Fluorescent Coumarins and Phosphorous-Containing Coumarin-Type Heterocycles via Palladium Catalyzed Cross-Coupling Reactions

Quantum-chemical calculations on the spectral properties of some aryl substituted 3- phosphonocoumarins were performed, and the effect of the substituents in the aryl moiety was evaluated. The structures possessing promising fluorescent properties were successfully synthesized via Suzuki and Sonogashira cross-coupling. The synthetic protocol was also applied for the phosphorous chemoisomer of 3-phosphonocoumarin, 1,2-benzoxaphosphorin, and their carboxylate analogues. The optical properties of the arylated and alkynylated products were experimentally determined. The obtained quantum-chemical and experimental results give the possibility for a fine tuning of the optical properties of phosphorous-containing coumarin systems by altering the substituent at its C-6 position

Synthesis and applications of coumarin derivatives

During the last few decades the interest in the synthesis and investigation of different coumarin derivatives and analogues has vastly increased mostly due to their multidisciplinary application in organic synthesis, agrochemistry, medicine, laser technologies, and etc. The object of our investigations is concerned on the chemical behaviors of these compounds because they are good acceptors in reactions with nucleophillic reagents, they can be used as dienophiles in Diels-Alder reaction, 1,3-bipolar cycloaddition reactions etc. The combination of coumarin structure and phosphono moiety assumes a biological activity, which can be a result of each of both units as well as a blend of both. It is clear that coumarins can be used as ligands in complexes with variety metal ions. Another aspect about coumarins which is of great interest for us is the possible photochemical properties of these compounds.Here we report reactions of cycloaddition and new rearrangement reaction resulting in potential biologically active derivatives

In Vivo Radioprotective Potential of Newly Synthesized Azomethine and Styrylquinoline Derivatives and a Natural Polyphenol: A Preliminary Study

The aim of the present study was to investigate the radioprotective activity of silymarin, a plant substance with hepatoprotective activity, of four newly synthesized structural derivatives of anthranilic acid azomethines, and alkyl-2-styrylquinolinic acid, as well as to establish and assess the influence of the solvent type and bioactive compound dose on the in vivo radioprotective potential of the natural and novel synthetic compounds. Male Wistar strain rats weighing 110–120 g were used for the in vivo experiments. Fifteen minutes after i.p. injection of the compounds, the experimental animals were irradiated by 8 Gy. Results indicate that the compound 2-{[(3,5-dihydro-2-hydroxyphenyl)methylen] amino}-benzoic acid in a dose of 60 mg/kg body weight exhibited the highest radioprotective effect, whereas the natural extract silymarin did not manifest radioprotective potential, even in high doses

Organic dyes in contemporary medicinal chemistry and biomedicine. I. From the chromophore to the bioimaging/bioassay agent

AbstractThe present review was provoked by the demand of a comprehensive overview on the recent scientific achievements revealing new horizons for advanced applications of organic dyes in service of contemporary medicinal chemistry, pharmacy and biomedicine. The review outlines the basic structural characteristics, physicochemical properties and biological activity of various dye families and suggests modified classifications of dyes according to their structural moieties and bioorganic functionalities serving the necessities of modern analytical chemistry and biochemistry. A major part of the review focuses on the pros and cons of the use of dyes as vectors in bioanalytic assays. The latter is based on comparative analyses of the limitations of some widely applied classical methodologies vs. the advantages and outcomes of the application of newly-designed dye molecules in modern dye-based bioassay techniques

Occurence of Psychosis in Dogs Reared in House, Farm and Kennels

This ethological study was  carried out to establish the occurrence of psychosis in dogs, reared both in-home (as a pet) and in dog kennels. The dogs housed in kennels were reared either individually (as working animals) or in groups (in kennels). All the pet dogs were reared alone in the households. The highest occurrence of psychotic states was encountered in stray dogs housed in kennels and followed by the pet dogs. These states were very rarely observed in individually reared dogs at farms and working dogs. The possible explanation is that they were submitted to less stressors due to good management at farms and the proper approach on the basis of their temperaments, i.e. their welfare was at the highest level

CHARACTERISTICS OF SOIL ACTINOMYCETES FROM ANTARCTICA

Forty-seven actinomyces strains were isolated from Antarctic soils - nineteen of them showed antagonistic activity against Gram-positive and Gram-negative bacteria. Six of the strains possessed a broad spectrum of antibacterial activity. Results obtained from the physiological and biochemical analyses including determination of 39 characteristics proved that two of the strains (23 and 29) were similar whereas all the rest differed among each other. Morphological studies indicated that the strains belonged to the genera Streptomyces, Actinomadura and Kitasatosporia. Antibacterial activity of three actinomycetes strains (designed as 29, 30 and 47) was confirmed in batch culture. They were active against clinical isolates from the species Staphylococcus aureus and Streptococcus pneumoniae. The three strains also showed antibacterial activity against the phytopathogenic bacteria Xanthomonas axonopodis pv. glycines, X. vesicatoria, X. axonopodis pv. phaseoli, Pseudomonas syringae pv. tomato and Clavibacter michiganensis, for which no biological means for control, had been developed yet. The broadest spectrum of antibacterial action had the strain 29. The antibacterial compounds produced by these strains probably possessed non-polar structure and consisted of several active components

CHARACTERISTICS OF SOIL ACTINOMYCETES FROM ANTARCTICA

Forty-seven actinomyces strains were isolated from Antarctic soils - nineteen of them showed antagonistic activity against Gram-positive and Gram-negative bacteria. Six of the strains possessed a broad spectrum of antibacterial activity. Results obtained from the physiological and biochemical analyses including determination of 39 characteristics proved that two of the strains (23 and 29) were similar whereas all the rest differed among each other. Morphological studies indicated that the strains belonged to the genera Streptomyces , Actinomadura and Kitasatosporia . Antibacterial activity of three actinomycetes strains (designed as 29, 30 and 47) was confirmed in batch culture. They were active against clinical isolates from the species Staphylococcus aureus and Streptococcus pneumoniae. The three strains also showed antibacterial activity against the phytopathogenic bacteria Xanthomonas axonopodis pv. glycines, X. vesicatoria, X. axonopodis pv. phaseoli, Pseudomonas syringae pv. tomato and Clavibacter michiganensis , for which no biological means for control, had been developed yet. The broadest spectrum of antibacterial action had the strain 29. The antibacterial compounds produced by these strains probably possessed non-polar structure and consisted of several active components