Cellular response to oxidative stress at sulfhydryl group receptor sites on the erythrocyte membrane

Ellman's reagent was used to induce an oxidative stimulus on the exofacial membrane sulfhydryl groups of the human erythrocyte. Thiol-disulfide exchange occurring extracellularly was monitored using resonance Raman spectroscopy, and intracellular changes were observed by 1H spin echo nuclear magnetic resonance spectroscopy of the intact cell. The stimulus caused oxidation and depletion of the glutathione pool, which was followed at higher concentrations of Ellman's reagent by a depletion of intracellular ergothioneine levels. Larger changes are induced intracellularly than would be expected from the stoichiometry of the reaction at the exofacial surface. A mechanism is proposed which links exofacial sulfhydryl receptor sites via the transport proteins to spectrin and glutathione. The consequences for the cellular redox balance of an extracellular stimulus of this type are discussed.     

New data on small mammals in the Kazakh Uplands

Small mammals were studied in the Kazakh Uplands in the spring and fall of 2008. The trapping studies revealed 10 species. Abundances of the animals were low in the four main distinct characteristic biotopes of Bayanaul National Park, but those of biotope dominants were high. In the Kazakh Uplands, rodents and insectivores are clearly restricted to certain biotopes. Biodiversity indices for small mammal communities are low, indicating that the community structure is disturbed.     

Preparation of chloroplast DNA from pea plastids isolated in a medium of high ionic strength

A simple, rapid, and inexpensive method for the preparation and purification of chloroplast DNA (cpDNA) from pea has been developed. The crucial step is the isolation of chloroplasts in a medium of high ionic strength (I congruent equal to 1.40 M). CpDNA from pea prepared according to this method has successfully been used for restriction enzyme mapping, Southern transfers, and cloning.     

Arsenic Bioaccumulation in Freshwater Fishes

The arsenic ambient water quality criterion (AWQC) for protection of human health via ingestion of aquatic organisms is currently 0.14 μ g/L. This AWQC is derived using a bioconcentration factor (BCF) of 44, which is a consumption-weighted average based on two data points for oysters and fish that was proposed by the U.S. Environmental Protection Agency in 1980 for broad application to freshwater and marine environments. This BCF is based on the assumption that bioaccumulation is a simple linear function of the exposure concentration. In the nearly quarter of a century since this BCF was promulgated, there have been additions to the arsenic bioaccumulation database and a broader scientific understanding of bioaccumulation mechanisms and how they can be applied to estimating tissue concentrations in aquatic organisms. From this database, we identified 12 studies of arsenic bioaccumulation in freshwater fishes in order to explore differences in laboratory-generated BCFs and field-generated bioaccumulation factors (BAFs) and to assess their relationship to arsenic concentrations in water. Our analysis indicates that arsenic concentrations in tissue and arsenic BAFs may be power functions of arsenic concentration in water. A power function indicates that the highest BCF values may occur at low background levels and may decrease as environmental concentrations increase above the ambient range.     

Changes in the Activity and Pattern of Hemolymph Esterases in the Larvae of Greater Wax Moth Galleria mellonellaL. (Lepidoptera, Pyralidae) during Mycosis

The extended pattern of multiple esterase forms has been revealed in the hemolymph of wax moth Galleria mellonellalarvae infected by the fungi Metarhizium anisopliae, Beauveria bassianaor Paecilomyces fumoso-roseus. The total esterase activity of the hemolymph also increases during mycosis. Mechanical damage of the cuticle, treatment with deltamethrin, and chilling of the caterpillars induced similar changes in the hemolymph pattern of esterase activity. Presumably, the changed spectrum and activity of the hemolymph esterases during mycosis is due to the damaged cuticle and epidermis cells.     

The spinal cord supports of vertebrae in the crown‐group salamanders (Caudata,Urodela)

The development of spinal cord supports (bony thickenings which extend into the vertebral canal of vertebrae) in primitive (Salamandrella keyserlingii) and derived (Lissotriton vulgaris) salamanders were described. The spinal cord supports develop as the protuberances of periostal bone of the neural arches in the anteroproximal part of the septal collagenous fibers which connect a transverse myoseptum with the notochord and spinal cord, in the septal bundle inside the vertebral canal. Spinal cord supports were also found in some teleostean (Salmo salar, Oncorhynchus mykiss) and dipnoan (Protopterus sp.) fishes. The absence of the spinal cord supports in vertebrates with cartilaginous vertebrae (lampreys, chondrichthyan, and chondrostean fishes) corresponds to the fact that the spinal cord supports are bone structures. The absence of the spinal cord supports in frogs correlates with the lack of the well developed septal bundles inside the vertebral canal. The spinal cord supports are, presumably, a synapomorphic character for salamanders which originated independently of those observed in teleostean and dipnoan fishes. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.     

A new semi-automated instrument to improve the fine needle aspiration procedure during breast lesion cell sampling

A large and increasing number of women in the western world will at some point during their life be investigated morphologically for some type of breast lesion. Fine Needle Aspiration (FNA) is one morphological method which is considered to be the fastest, cheapest and the most patient-friendly approach. However, the frequency of conclusive samples using this method varies and is often too low, especially when performed by unexperienced operators. In this study we have developed and tested a new semi-automated instrument (“CytoTest”) designed for FNA which is intended to improve the efficacy of the technique by increasing the percentage of conclusive samples. A total of 443 consecutive aspiration procedures on palpable breast lesions were performed to compare this new “CytoTest” equipment with the standard protocol using the same type of needles. We conclude that by increasing the extent and frequency of the reciprocatory motions used by an experienced sampling operator as well as enhancing the ejection pressure, the cellular yield can be increased almost three folded compared to the standard protocol. For cases with high amounts of non-diagnostic material (such as blood or cystic fluid) which were discarded, up to four times more sample could be obtained. Furthermore, the frequency of sparse samples under 1 mg was halved with use of the “CytoTest”.