A-like cells of the gastric mucosa as a possible source of prostaglandins

AL cells of the oxyntic stomach area were studied in rats using ultrastructurometric technique. High-threshold, short-term direct electrical vagostimulation (5 V, 4 msec, 30 Hz, 10 sec) was performed in experimental group of 12 animals. Animals were killed 1, 10 and 30 min after stimulation. High post-stimulation lipolytic activity of AL cells and intensification of "granule autophagy" phenomenon were noted. Our findings as well as the literature data suggest a hypothesis on possible prostaglandin production by AL cells. Direct evidence in favour of this hypothesis is difficult to obtain due to the lack of sufficiently reliable methods of their morphological detection in cells.     

Bioluminescent Toxicity Assay of Polyethylenimine-Based Sorbents

Applied Biochemistry and Microbiology - The toxicity of polyethylenimine-based sorbents and their extracts was evaluated, and their effect on the bioluminescence of Photobacterium phosphoreum...     

A Cytoplasmic Male Sterility-Associated Rearrangement of the Mitochondrial cobGene Region in Sugar Beet Beta vulgarisL.

Physical maps of the cobmtDNA region were constructed and compared between sugar beet Beta vulgarisL. plants with normal fertility and with cytoplasmic male sterility (CMS). A CMS-associated rearrangement did not affect the coding region of coband combined two mtDNA regions which are normally about 150 kb apart. Two point substitutions were found in the 3"-untranslated region of cob.     

Interplay between recombinant Hsp70 and proteasomes: proteasome activity modulation and ubiquitin-independent cleavage of Hsp70

The heat shock protein 70 (Hsp70, human HSPA1A) plays indispensable roles in cellular stress responses and protein quality control (PQC). In the framework of PQC, it cooperates with the ubiquitin-proteasome system (UPS) to clear damaged and dysfunctional proteins in the cell. Moreover, Hsp70 itself is rapidly degraded following the recovery from stress. It was demonstrated that its fast turnover is mediated via ubiquitination and subsequent degradation by the 26S proteasome. At the same time, the effect of Hsp70 on the functional state of proteasomes has been insufficiently investigated. Here, we characterized the direct effect of recombinant Hsp70 on the activity of 20S and 26S proteasomes and studied Hsp70 degradation by the 20S proteasome in vitro. We have shown that the activity of purified 20S proteasomes is decreased following incubation with recombinant human Hsp70. On the other hand, high concentrations of Hsp70 activated 26S proteasomes. Finally, we obtained evidence that in addition to previously reported ubiquitin-dependent degradation, Hsp70 could be cleaved independent of ubiquitination by the 20S proteasome. The results obtained reveal novel aspects of the interplay between Hsp70 and proteasomes.     

Diptera in Nests of the Fieldfare <Emphasis Type="Italic">Turdus pilaris</Emphasis> in Moscow City

The composition of dipterans inhabiting fieldfare nests in a big city was studied for the first time, based on material collected soon after chick fledging. Larvae of 21 species belonging to 14 families were found, including saprophages, necrophages, and predators (Scatopsidae, Ceratopogonidae, Phoridae, Chloropidae, Anthomyiidae, etc.), and also Protocalliphora azurea (Fallén, 1816) (Calliphoridae) and Neottiophilum praeustum (Meigen, 1826) (Neottiophilidae) known as bloodsucking ectoparasites of nestlings. Larvae of P. azurea (up to 121 per nest) were found in both early (April–May) and late (May–June) nests. Larvae of N. praeustum (up to 299 per nest) were recorded only in late nests. The two species occurred both separately and jointly in one nest, with N. praeustum dominating numerically. The seasonal differences in the development of these two parasitic species may account for their high abundance in such ephemeral habitats. Larvae of Trypocalliphora braueri (Hendel, 1901), a subcutaneous parasite of nestlings of many bird species, were not found in the fieldfare nests. A key to the larvae of the three fly species parasitizing nestlings in European Russia is given.     

MAGO-IX Experiment

The results of the last (in the thermonuclear program “Magnetic compression”) MAGO-IX experiment with a plasma chamber including a third compartment designed to compress plasma with a converging liner are presented. An X-ray pulse consisting of an intense peak of 1-μs duration, followed by a low-intensity tail with a duration of more than 10 μs, was recorded. In the MAGO-IX experiment, the neutrons were generated mainly in the third compartment. A neutron yield of 2 × 10¹² was obtained. The results demonstrate that the expected compression of preheated plasma in chambers similar to MAGO-IX is promising for achieving thermonuclear ignition.