Species composition and ecological structure of ground beetles (Coleoptera, Carabidae) communities as biological indicators of the agro-environmental sustainability.

Intensification of crop cultivation can have detrimental environmental consequences that however can be prevented by monitoring of the specific biological indicators sensitive to changes in the ambient environment. In this study the impact of crop type (spring wheat and corn) and cultivation intensity on the community of ground beetles (Coleoptera: Carabidae) in the forest-steppe of Western Siberia was investigated. A total of 39 species from 15 genera were collected. Ground beetles' community was characterized by a high evenness of species distribution across the agroecosystems. The average Jaccard's similarity index for species presence/absence was 65%, and for abundance it was 54%. The significant difference in the distribution of predatory and mixophytophages ground beetles in wheat crops (U test, P < 0.05) can be justified by the constant suppression of the weed component and the use of insecticides that lead to the dominance of the predators. Fauna of wheat crops was more diverse than that in corn (Margalef index, U test, P < 0.05). No significant differences in biological diversity indexes, except for the Simpson dominance index (U test, P < 0.05, wheat), were found in ground beetle communities in crops at different levels of intensification. A certain differentiation of predatory species was caused by the selective occurrence of the litter-soil species, especially abundant in the row-crop. The specificity of the ground beetle community of corn crops may have been caused by repeated inter-row tillage, which influenced the increase in porosity and topsoil relief and contributed to the creation of favorable microclimatic conditions. In general, the applied level of agrotechnological intensification had no significant effect on the species composition and ecological structure of beetle communities in agrolandscapes. The use of bioindicators made it possible to assess the environmental sustainability of the agricultural environment and also creates the prerequisites for the development of ecologically directed correction of agrotechnological operations in agroecosystem management.

Development of GC-MS/MS method with programmable temperature vaporization large volume injection for monitoring of 17ß-estradiol and 2-methoxyestradiol in plasma.

Monitoring of estradiol and its metabolites in biological samples is essential for the accurate diagnosis of a number of endocrine diseases. In this study, a sensitive, precise and specific GC-MS/MS method for the quantification of 17ß-estradiol (17-BE) and its main metabolite, 2-methoxyestradiol (2-MEOE), in plasma was developed and validated. Plasma concentrations of these steroids are currently investigated as diagnostic markers for pre-eclampsia, a systematic disorder of pregnancy and a leading cause of maternal and fetal morbidity and mortality worldwide. The method comprised treatment of the plasma sample by protein precipitation and subsequent isolation of steroids by solid phase extraction, derivatization of steroids by trifluoroacetic anhydride and GC-MS/MS analysis of the derivatized steroids. The large volume (10 µL) injection with the assistance of a Programmed Temperature Vaporization (PTV) injector in solvent split mode allowed a substantial increase in the sensitivity of the method. The ion trap MS was operated in optimized Product Ion Scan. By increasing the damping gas flow in the ion trap from the conventional 0.3 mL min(-1) to 2 mL min(-1), ion fragmentation was reduced and the instrument response was enhanced substantially. As a result, mass spectra with predominant molecular ions were acquired and molecular ions of the steroids of interest were used as precursor ions thus increasing specificity of the method. Under optimized GC-MS/MS conditions in product ion mode, the Limit of Detection (LOD) of the analyzed steroids ranged from 18.4 pg mL(-1) for 17-BE to 5.5 pg mL(-1) for 2-MEOE (S/N=3). The instrument response was linear in the investigated concentration range from 0.1 to 10 ng mL(-1) with R(2)>0.99 for 17-BE and 2-MEOE. The intra-batch accuracy obtained for quality control samples at the concentration levels of 0.1, 1, 3, 7 ng mL(-1) ranged from 94.9% to 109.9% for 17-BE and from 99.9% to 104.5% for 2-MEOE.

Acute poisoning with carbamate pesticides: the Cretan experience.

In Crete, in southern Greece, a number of fatal carbamate poisonings were investigated over a period of 2 years, from 1991 to 1993. Five cases are reported, involving the fatal ingestion of methomyl (Lannate), a cholinesterase-inhibiting carbamate insecticide. Analysis of samples of blood plasma and serum showed more than 90% inhibition of cholinesterase. The blood methomyl concentrations had a mean value of 26.7 mg/l, and a range of 5.6-57.0 mg/l. These values are much higher than those previously reporter in similar cases (0.57-1.4 mg/l). Methomyl concentrations in organs and tissues were found to be significantly lower than those in blood and vitreous humour.

The analysis of methomyl, a carbamate pesticide, in post-mortem samples.

Extraction procedures and analytical methods are described for the quantitation of methomyl, a carbamate insecticide, in autopsy tissue and fluid samples. The analytical results from case work demonstrate the rapid metabolism of methomyl in the body.

Phthalocyanine mediated photodynamic thrombosis of experimental corneal neovascularization: effect of phthalocyanine dose and irradiation onset time on vascular occlusion rate.

The aim of this study was to evaluate the possible influence of phthalocyanine dose and of time interval between phthalocyanine injection and irradiation commencement on the rate of experimental corneal neovascularization photodynamic thrombosis in albino rabbits. New corneal vessels were irradiated with a diode laser (670 nm, 2 mW) after the intravenous injection of chloroaluminum sulfonated phthalocyanine. Different animals were irradiated either 5 min after the injection of different phthalocyanine doses (3, 6, 8, 12, or 14 mg/kg), or at different times (5 min, 24 h, or 58 h) after a standard phthalocyanine dose (3 mg/kg) injection. Irradiation time necessary for vascular occlusion was recorded. Decrease of phthalocyanine dose as well as delay of irradiation onset resulted in a statistically significant increase of irradiation time. Electron and light histological examination revealed platelet thrombi inside irradiated corneal new vessels. Damage in the vascular endothelial cell membrane and in intercellular contact structure was noted, leading to disorganization of the endothelial cells layer and death of most endothelial cells. These results indicate that both early commencement of irradiation after phthalocyanine injection and phthalocyanine dose increase accelerate the rate of phthalocyanine mediated corneal neovascularization photodynamic thrombosis. Thrombosis seems to result from photochemically induced vascular endothelial cell damage.