Numerical characteristics of synaptic vesicular apparatus structure in the dorsal horn of the cat spinal cord

Statistical parameters characterizing the structure of the vesicular apparatus of presynaptic endings (PE) were determined from the findings of ultrastructural morphometric analysis of 135 synapses in the dorsal horn of the cat spinal cord. Quantitative estimates of vesicles in the PE (averaging about 470) were obtained, based on stereometric principles. The bimodal pattern of distribution of distances from the center of each vesicle to the nearest portion of the active zone was demonstrated — viewed as the structural correlate of the two-pool model of transmitter storage. The possibility of classifying PE according to the sign of vesicle spatial distribution is discussed as well as the relationship between this distribution and parameters of transmitter mobilization and synaptic release.Dnepropetrovsk State University. A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 21, No. 5, pp. 597–605, September–October, 1989.     

A technique for the assessment of the cytotoxic capacity of CD8+ lymphocytes based on phase images

A novel technique for the assessment of cytotoxic capacity, which is a characteristic of the state of immune-system cells, has been proposed. Using coherent phase microscopy, perforin granules have been detected and described in the cytoplasm of live CD8+ lymphocytes. According to the analysis of phase images, the parameters of perforin granules in the cell were quantitatively assessed. Their average values were calculated as follows: the projected area on the image plane, 15 ± 7 μm²; phase volume, 0.94 ± 0.24 μm³; and the dry weight of the granules, 0.52 ± 0.11 pg. Taking the advantage of this technique, it appears possible to determine cytotoxic capacity using a small number of live cells without employing fluorescent-labeled probes.     

Preparatory extraction of 5'-oligoribonucleotides using ribonuclease from cobra venom]

Cobra (Naja oxiana) venom ribonuclease, which catalyses hydrolysis of polyribonucleotides to 5'-oligonucleotides, was used to obtain preparatively isoplit oligonucleotide fractions, containing 2-30 nucleotides. The yield of hydrolysis products varied depending on the degree of hydrolysis. Hydrolysis rates of different polynucleotides were studied. Hydrolysis rate of polyadenylic acid was 20 times as high as that for polyuridylic acid. Quantitative ratios of isoplit fractions did not vary significantly under similar degree of hydrolysis of polyadenylic and polyuridilic acids. Chromatography on QAE-Sepahdex in ammonium bicarbonate concentration gradient containing 15% dioxan was used to separate enzymatic hydrolysates of polynucleotides, which permitted to bring the fraction isolation to simple evaporation.     

A New Genus and Species of the Damselfly Family Hemiphlebiidae from the Lower Cretaceous Chernovskie Kopi Locality (Eastern Transbaikalia)

Thairia transbaikalica Felker et Vasilenko, gen. et sp. nov. (Odonata, Hemiphlebiidae) from the Mesozoic Chernovskie Kopi locality is described. A short review of known genera of Hemiphlebiidae is provided. Relative age of enclosing rocks is discussed.     

Development of Magnetic Biosorbents and Their Application in Immunoassays of Microbial Antigens

The feasibility of rendering erythrocytes magnetic and thereby creating magnetic biosorbents through a room temperature exposure to 25–37% iron (II) sulfate solution for 48 ± 2 h followed by exposure to 15–25% aqueous ammonia solution for 48 ± 2 h (with drying after each procedure) was demonstrated. The feasibility of immobilizing ligands on magnetic erythrocytes and obtaining biological magnetic immunosorbents (BMISs) for further use in EIAs for plague and tularemia antigens was demonstrated. The sensitivity of EIAs involving BMISs amounted to 10 ng/ml and 100 microbial cells per 1 ml. The relative error did not exceed 8%.     

<Emphasis Type="Italic">Methylophaga muralis</Emphasis> Bur 1, a haloalkaliphilic methylotroph isolated from the Khilganta soda lake (Southern Transbaikalia,Buryat Republic)

A haloalkaliphilic restricted facultative methylotroph, strain Bur 1, which used methanol, methylated amines, and fructose as carbon and energy sources, was isolated from the soda Lake Khilganta (Buryat Republic, Russia). The cells were gram-negative non-spore-forming, motile rods reproducing by binary fission. The organism was aerobic, reduced nitrates to nitrites. Growth occurred at temperatures from 4 to 37°C (optimum at 25–29°C), pH 7.5–10.5 (optimum at 8.5–9.5), and NaCl concentration in the medium from 0.05 to 10.0% NaCl (optimum at 3–4%). Ectoine, glutamate, and sucrose were accumulated as osmoprotectants. Activity of the enzymes of de novo ectoine biosynthesis were detected. The organism utilized C₁ compounds via the KDPG variant of the ribulose monophosphate pathway. The DNA G + C content was 44.67 mol %. Based on the similarity of the 16S rRNA gene sequences (94.7–99.1%) and the results of DNA–DNA hybridization (24–74%) with type strains of the neutrophilic and alkaliphilic Methylophaga species, the isolate was identified as Methylophaga muralis Bur 1 (VKM B-3046 = DSM 103617). The genome of M. muralis Bur 1 contained 2585 protein-encoding genes; 634 proteins with unidentified functions were predicted. Three rRNAs (5S, 16S, and 23S) and 38 tRNAs were identified. Apart from the mxaFJGIRSACKLDEH classical cluster of methanol oxidation genes, the xoxF gene was found. Methylamine was oxidized to formaldehyde by methylamine dehydrogenase and via the N-methylglutamate pathway. Orthologs of type III glutamine synthetases were revealed in the genome. The operons of ectoine and sucrose biosynthesis, ectRABC-ask and sps-spp-fruK-ams, were found. The genomes of M. muralis Bur 1 and M. lonarensis MPL^T, unlike that of M. nitratireducenticrescens JAM1^T, were found to contain the genes encoding the proteins of bicarbonate transport.     

Insect ovipositions on aquatic plant leaves <Emphasis Type="Italic">Quereuxia</Emphasis> from the Upper Cretaceous of the Amur region

New form taxa of insect ovipositions on aquatic plant leaves Quereuxia from the Campanian locality of Udurchukan (Amur Region) are described. Endophytic ovipositions Paleoovoidus flabellatus sp. nov. and P. arcuatus sp. nov. do not differ in shape from ovipositions of recent damselflies. Exophytic ovipositions Palaexovoidus ovoideus gen. et sp. nov., P. catenulatus sp. nov., P. multus sp. nov., and P. amplus sp. nov. belong to insects that develop in the water, probably dragonflies of the suborder Anisoptera. A new family Palaexovoididae fam. nov. is erected.     

Oxidoreductase activities of polyclonal IgGs from the sera of Wistar rats are better activated by combinations of different metal ions

It was shown that IgGs purified from the sera of healthy Wistar rats contain several different bound Me2+ ions and oxidize 3,3'-diaminobenzidine through a H2O2-dependent peroxidase and H2O2-independent oxidoreductase activity. IgGs have lost these activities after removing the internal metal ions by dialysis against EDTA. External Cu2+ or Fe2+ activated significantly both activities of non-dialysed IgGs containing different internal metals (Fe > or = Pb > or = Zn > or = Cu > or = Al > or = Ca > or = Ni > or = Mn > Co > or = Mg) showing pronounced biphasic dependencies corresponding to approximately 0.1-2 and approximately 2-5 mM of Me2+, while the curves for Mn2+ were nearly linear. Cu2+ alone significantly stimulated both the peroxidase and oxidoreductase activities of dialysed IgGs only at high concentration (> or = 2 mM), while Mn2+ weakly activated peroxidase activity at concentration >3 mM but was active in the oxidoreductase oxidation at a low concentration (<1 mM). Fe2+-dependent peroxidase activity of dialysed IgGs was observed at 0.1-5 mM, but Fe2+ was completely inactive in the oxidoreductase reaction. Mg2+, Ca2+, Zn2+, Al2+ and especially Co2+ and Ni2+ were not able to activate dialysed IgGs, but slightly activated non-dialysed IgGs. The use of the combinations of Cu2+ + Mn2+, Cu2+ + Zn2+, Fe2+ + Mn2+, Fe2+ + Zn2+ led to a conversion of the biphasic curves to hyperbolic ones and in parallel to a significant increase in the activity as compared with Cu2+, Fe2+ or Mn2+ ions taken separately; the rates of the oxidation reactions, catalysed by non-dialysed and dialysed IgGs, became comparable. Mg2+, Co2+ and Ni2+ markedly activated the Cu2+-dependent oxidation reactions catalysed by dialysed IgGs, while Ca2+ inhibited these reactions. A possible role of the second metal in the oxidation reactions is discussed.