Pharmacokinetic substantiation of ceftriaxone prophylaxis of hereditary syphilis]

Ceftriaxone concentrations in sera of females at various terms of pregnancy and in certain organs and tissues of the fetus were assayed. The antibiotic was administered intramuscularly in doses of 1.0 and 0.5 g once a day. The concentrations were estimated by HPLC. The ceftriaxone levels in the specimens were tens times higher than the minimal treponemocidal concentration (0.01 mcg/ml). The doses were sufficient for the prophylaxis of hereditary syphilis. Meanwhile, the clinical practice indicated that duration of the ceftriaxone prophylaxis of the pregnant females should be increased.     

Silver-Containing Humic Substance-Based Nanocomposites—Agents for Healing of Potatoes from the Ring Rot

The influence of silver-containing humic substance (HS)-based nanocomposites (NCs) obtained from mud, shale, and coals of three kinds of deposits in Mongolia on the viability and ability to biofilm formation of a phytopathogenic gram-positive bacterium Clavibacter michiganensis subsp. sepedonicus (Cms), as well as peroxidase activity and potato plant growth in vitro, has been investigated. The maximum reduction of the viability of bacterial cells was found in the case of incubation with HS-mu/Ag NC and HS-coal/Ag NC. It was found that HSs, including HS-mu and HS-sl, and NCs synthesized on the base of these HSs, HS-mud/Ag NC and HS-sl/Ag NC reduce more than twofold the activity of peroxidase in potato tissues. It was also found that HS-co and HS-coal/Ag NC stimulate the potato peroxidase activity, as well as biofilm formation of Cms bacterium. No negative effect of the studied NCs on the growth of potato has been revealed. Moreover, NC HS-mud/Ag based on mud had a stimulating effect on leaf formation in plants.     

Transplantation of stem/progenitor cells of human brain into the brain of adult rats

We studied the development of stem/progenitor cells of the human brain transplanted in the adult rat brain after reproduction in an in vitro tissue culture. It was preliminarily shown by the immunological methods that the stem cells grown in a medium with growth factors formed neurospheres, which were heterogenous and contained both stem and progenitor cells of the human brain. The cells were implanted in the hippocampus, striatum, or lateral ventricle of the rat brain as a suspension or aggregates (neurospheres) and their behavior and differentiation were studies within 10, 20, and 30 days using the morphological and immunochemical methods. The cultured cells of the human brain continued their development in the rat brain, migrated, and formed neurons and astrocytes. The white mater fibers, lateral ventricle wall, and perivascular spaces served as the main pathways of migration. The neuronal differentiation was shown by staining with antibodies to beta-tubulin III, neurofilaments-70, and calbindin. Some growing nerve cells had long processes with growth cones. At the same time, some transplanted cells retained the undifferentiated state within one month after the implantation, as shown by the vimentin expression.     

EFFECTS OF HUMAN ACTIVITIES ON STRUCTURE AND COMPOSITION OF WOODY SPECIES OF THE NOKREK BIOSPHERE RESERVE OF MEGHALAYA,NORTHEAST INDIA

Aims Our study was conducted in the Nokrek Biosphere Reserve (NBR) in the Garo hills districts of Meghalaya, Northeast India. Our aim was to assess the effects of human activities on plant diversity,population structure and regeneration.Methods We selected a representative 1.2 hm2 stand in both the core and buffer zones of NBR. Structure and composition were determined by randomly sampling square quadrats, population structure was assessed by determining age structure, and regeneration was assessed by measuring densities of seedling, sapling and adult trees.Important findings More woody species were recorded from the core zone than the buffer zone (87 vs. 81 species), and there were a large number of tropical, temperate, and Sino-Himalayan, Burma-Malaysian and Malayan elements, primitive families and primitive genera. The trees were distributed in three distinct strata,canopy, subcanopy and sapling. Subcanopy and sapling layers had the highest species richness (81％ -88％ ). Lauraceae and Euphorbiaceae were the dominant families in terms of the number of species, and a large number of families were represented by single species. Most woody species (57 ％ - 79 ％ ) were contagiously distributed and had low frequency ( ＜ 20％ ). Although stand density was high in the buffer zone, its basal area was low compared to the stand in the core zone. Low similarity and high β-diversity indicate marked differences in species composition of the stands. Shannon diversity index was high in both the stands, while Simpson dominance index was low. The diameter-class distribution for dominant species revealed that the most had a large number of young individuals in their populations. Preponderance of tree seedlings, followed by a steep decline in population density of saplings and adult trees, indicated that the seedling to sapling stage was the most critical in the life cycle of the tree populations. Most species (42 ％ - 48 ％ ) had no regeneration,25 ％ - 35 ％ had good/fair regeneration, and the rest had poor regeneration or reoccurred as immigrants.