Dispersal of four fritillary butterflies within identical landscape

Both species-specific traits and landscape configuration, such as area and connectivity of habitat patches plus the character of uninhabitable matrix, affect animal movements in fragmented landscapes. Difficulties with disentangling species-specific and landscape effects have obscured comparisons among species, hindering the understanding of dispersal in metapopulations. To circumvent this complication, we performed a mark–recapture study of four related nymphalid butterflies within identical landscape and in single season. The studied species were three Melitaeinae checkerspots (Euphydryas aurinia, Melitaea athalia, Melitaea diamina) and one Argynnini fritillary (Brenthis ino). Applying the Virtual Migration model revealed that (1) except for mortality within habitat, model parameters differed from those found for the studied species elsewhere; (2) the three Melitaeinae species were more akin in movement parameters than the Argynnini representative (i.e., B. ino); (3) within Melitaeinae, differences between sexes were more prominent than differences among species; (4) Melitaeinae males left natal patches more readily than females, while the opposite applied to B. ino; (5) males of M. diamina and both sexes of B. ino exhibited highest values of dispersal mortality; (6) except for females of M. diamina and both sexes of B. ino, immigration and emigration scaled with area in females but not in males. Finding (1) demonstrates that geometry of habitat network affects mobility considerably and that transferring dispersal parameters across systems is unwarranted. Still, (2–6) demonstrate that within identical networks, related species follow similar dispersal patterns, suggesting that conservation scenarios suitable for a well-studied model species would suite related species as well.     

Sensitivity of bone marrow cells damaged by antitumor drugs to cytotoxic action of effectors of a normal spleen

Different cytogenetic effects in bone marrow cells induced by antitumor drugs with different mechanisms of action was studied. The treatment of adriablastine causes the appearance of chromatid deletion, vinblastine-polyploid cells, cyclophosphamide-chromosomal and chromatid aberration in mice. It was shown that bone marrow cells with cytogenetic damage have altered susceptibility to normal spleen cells-effectors cytotoxic action.     

Pharmacokinetics of cephalexin and cephradine in surgical patients]

Pharmacokinetics of 2 oral cephalosporin antibiotics, i.e. cephalexin and cephradin in surgical patients with normal function of the liver and kidneys was studied. Both the drugs were satisfactorily absorbed into the blood reaching the maximum level in 1 hour. The antibiotics were determined in close concentrations in the blood serum of the patients during 5 hours of the observation. No differences in the time of a two-fold decrease in the antibiotic serum level and the value of the area limited by the antibiotic blood level were found. Cephalexin and cephradin were excreted with the urine in equal amounts.     

Method of membrane filtration for determining the sterility and microbial contamination of antibiotics]

During membrane filtration antibiotics belonging to different chemical groups are strictly absorbed on the filters. When the filters are put into liquid thioglycol medium, the residual amounts of the antibiotics on the filters did not prevent the growth of sensitive microflora experimentally added to the drug. When the filter was put onto solid nutrient medium, only resistant forms of the microbes grew as a rule on its surface, the amount of the grown microbes being 26--43 per cent of the added one. The sensitive microbes grew only in the amount of 0.3--1.3 per cent. Subsequently the residues of the antibiotic adsorbed on the filter inhibited the growth of the sensitive and partially resistant microflora.     

Genomic analysis unveils reduced genetic variability but increased proportion of heterozygotic genotypes of the intensively managed mezcal agave,Agave angustifolia

Premise

The central Oaxaca Basin has a century-long history of agave cultivation and is hypothesized to be the region of origin of other cultivated crops. Widely cultivated for mezcal production, the perennial crop known as “espadín” is putatively derived from wild Agave angustifolia. Nevertheless, little is known about its genetic relationship to the wild A. angustifolia or how the decades-long clonal propagation has affected its genetics.

Methods

Using restriction-site-associated DNA sequencing and over 8000 single-nucleotide polymorphisms, we studied aspects of the population genomics of wild and cultivated A. angustifolia in Puebla and Oaxaca, Mexico. We assessed patterns of genetic diversity, inbreeding, distribution of genetic variation, and differentiation among and within wild populations and plantations.

Results

Genetic differentiation between wild and cultivated plants was strong, and both gene pools harbored multiple unique alleles. Nevertheless, we found several cultivated individuals with high genetic affinity with wild samples. Higher heterozygosity was observed in the cultivated individuals, while in total, they harbored considerably fewer alleles and presented higher linkage disequilibrium compared to the wild plants. Independently of geographic distance among sampled plantations, the genetic relatedness of the cultivated plants was high, suggesting a common origin and prevalent role of clonal propagation.

Conclusions

The considerable heterozygosity found in espadín is contained within a network of highly related individuals, displaying high linkage disequilibrium generated by decades of clonal propagation and possibly by the accumulation of somatic mutations. Wild A. angustifolia, on the other hand, represents a significant genetic diversity reservoir that should be carefully studied and conserved.

     

Ichthyoplankton in the plankton community of the western sector of the Black Sea in October 2005

Data on the numbers, species composition, and spatial distribution of ichthyoplankton, mesoplankton, and jelly-bodied microplankton in the western sector of the Black Sea in October 2005 are presented. A decrease in the predatory impact of the comb jellyfish Mnemiopsis leidyi on mesoplankton is recorded, which promoted the formation of favorable trophical conditions for larval fish survival. In the 1990s in the study area, the proportion of larvae with empty stomachs reached 80–90%; in October 2005, all the studied larvae were with food.     

Functional and structural changes in the surface of human erythrocytes after irradiation with UV rays of various wave lengths. I. The expression of ABO and rhesus system antigens

UV irradiation (254 nm) in doses increasing erythrocyte haemolysis by 5, 10, 18 and 28 per cent was found to stimulate, by 2--16 times, the agglutination activity of ABO and Rh system antigens. The stimulation effect was the higher the lower the antigen activity before irradiation. In the Rh-negative (Rh-) erythrocytes, irradiation induced manifestation of the Rh0(D)-antigen specific activity suggesting that this antigen may be present in the Rh- erythrocyte membrane. The expression of Rh0(D)-antigen in Rh- erythrocytes, the stimulation of its activity in Rh-positive cells, and the activation of ABO system antigens may result from a photochemical destruction of the outer perimembraneous layer and release some of its components which stain in situ with alcian blue to be presumably glycoproteins. This effect is necessary to keep in mind when UV-irradiated blood transfusion is performed in therapeutic aims Rh- patients.     

Using operonic gene pairs to set the threshold correlation coefficient for differently expressed genes

We have developed an approach to estimating the correlations in the noise component of gene expression data. An efficient noise reduction technique has been suggested. The resulting methods have been applied to E. coli microarray data and tested on SOS response modulated genes.     

The activity of beta-hydroxy-beta-methylglutaryl-CoA reductase in the soluble fraction of rat liver]

Assay conditions are worked out for determination of activity of beta-hydroxy-beta-methylglutaryl-CoA reductase (HMG-CoA reductase) in 140.000 g supernatant fraction of the rat liver. Some kinetic properties of the enzyme are studied: the activity dependency on the incubation time, protein concentration, pH, glutathione, dithiothreitol and HMG-CoA contents in the incubation medium. The effect of Triton WR 1339 on the activity of HMG-CoA reductase in the liver 140.000 g supernatant and microsomal fractions is comparatively studied. Diurnal activity variations of soluble and microsomal enzymes are also investigated. It is suggested that the rat liver HMG-CoA reductase in the 140.000 g supernatant fraction is not identical to the enzyme located in the microsomal fraction.