Diagnostic test systems based on the immunoenzyme method in leprosy

Diagnostic test systems for the detection of IgG and IgM to Mycobacterium leprae in the blood sera of leprosy patients and armadillos experimentally infected with M. leprae have been developed on the basis of the indirect immunoperoxidase assay. The possibility has been shown of prognosing the activity of the leprotic process in leprosy patients and the results of the experimental infection of armadillos by the dynamic increase of antibody reactions with the development of the infection.     

Synthesis of new olean-18(19)-ene derivatives from allobetulin

New olean-18(19)-ene triterpenoids were effectively synthesized by the interaction of allobetulin or its acetate with phosphorous oxychloride in refluxing pyridine. The structures of the synthesized 17-chloromethyloleane-18(19)-enes were confirmed by NMR spectroscopy and X-ray analysis.     

Comparison of optimization methods for fed-batch cultures of hybridoma cells

Two methods for the calculation of optimal trajectories for the input variables of a fed-batch culture of hybridoma cells are compared. It pointed out that a gradient method based on Pontryagins' minimum principle based yields a significant better performance with respect to computational effort and the calculated minimum than a dynamic programming approach which has been presented in a previous paper [1] as the most suitable method.     

Crystallization and preliminary crystallographic studies of the decadeoxyoligonucleotide d(CpGpTpApCpGpTpApCpG)

Crystals of the self-complementary decadeoxyoligonucleotide d(CpGpTpApCpGpTpApCpG) have been grown from a solution containing [Co(NH3)6]Cl3 and spermine. The amber-colored crystals are hexagonal and belong to the space group P6(5) (or P6(1] with unit cell parameters a = 17.93 A, c = 43.41 A. Precession photography and molecular packing considerations indicate that the unit cell consists of a 12 nucleotide duplex. The asymmetric unit, therefore, is a disordered duplex dimer in which each pyrimidine-purine base-pair is occupied 60% of the time by a C . G pair and 40% of the time by a T . A pair. The above considerations and preliminary structure analysis reveal that this alternating pyrimidine-purine oligomer assumes a Z-DNA conformation.     

In vitro modulation using a synthetic antioxidant of the stimulus-induced formation of cyclic AMP

The in vitro treatment of membranes isolated from different rat organs with a water-soluble synthetic antioxidant has resulted in the change of basal and stimulus-induced adenylate cyclase activity. It is believed that the antioxidant effect is realized rather at the level of signal transfer from activated receptor to adenylate cyclase than at the level of agonist-receptor interaction.     

Purification of recombinant proteins with an example of tumor necrosis factor thymosin-α1

Hybrid protein, cancer necrosis factor thymosin-α1 (TNF-T), when synthesizing in strain-producer of Escherichia coli SG200-50 with plasmid pThy315, was a part of “inclusion bodies” mostly in the form of a high-molecular complex with other proteins due to the S-S bonds formation. An approach of purification of TNF-T has been proposed, which is based on the destruction of the complex in the presence of sodium dodecylsulfate (DDS-Na) and dithiotreitol (DDT) followed by gel-filtration on Sephadex G-100 and renaturation by ultrafiltration on hollow fibers. The method allows the isolation of electrophoretically homogeneous TNF-T containing no DDS-Na and having high cytotoxic activity against cancer cells of mouse adenocarcinome L-929. The yield of TNF-T achieved 80% relative its content in biomass and 30% relative the total protein.     

Water inputs across a tropical montane landscape in Veracruz,Mexico: synergistic effects of land cover,rain and fog seasonality,and interannual precipitation variability

Land‐cover change can alter the spatiotemporal distribution of water inputs to mountain ecosystems, an important control on land‐surface and land‐atmosphere hydrologic fluxes. In eastern Mexico, we examined the influence of three widespread land‐cover types, montane cloud forest, coffee agroforestry, and cleared areas, on total and net water inputs to soil. Stand structural characteristics, as well as rain, fog, stemflow, and throughfall (water that falls through the canopy) water fluxes were measured across 11 sites during wet and dry seasons from 2005 to 2008. Land‐cover type had a significant effect on annual and seasonal net throughfall (NTF <0=canopy water retention plus canopy evaporation; NTF >0=fog water deposition). Forest canopies retained and/or lost to evaporation (i.e. NTF<0) five‐ to 11‐fold more water than coffee agroforests. Moreover, stemflow was fourfold higher under coffee shade than forest trees. Precipitation seasonality and phenological patterns determined the magnitude of these land‐cover differences, as well as their implications for the hydrologic cycle. Significant negative relationships were found between NTF and tree leaf area index (R²=0.38, P<0.002), NTF and stand basal area (R²=0.664, P<0.002), and stemflow and epiphyte loading (R²=0.414, P<0.001). These findings indicate that leaf and epiphyte surface area reductions associated with forest conversion decrease canopy water retention/evaporation, thereby increasing throughfall and stemflow inputs to soil. Interannual precipitation variability also altered patterns of water redistribution across this landscape. Storms and hurricanes resulted in little difference in forest‐coffee wet season NTF, while El Niño Southern Oscillation was associated with a twofold increase in dry season rain and fog throughfall water deposition. In montane headwater regions, changes in water delivery to canopies and soils may affect infiltration, runoff, and evapotranspiration, with implications for provisioning (e.g. water supply) and regulating (e.g. flood mitigation) ecosystem services.     

Distribution of the antimonate precipitate in normal and segregated nucleoli after potassium pyroantimonate fixation

Fixation with a saturated aqueous solution of potassium pyroantimonate produces electron-opaque antimonate deposits in the nucleoli of lutheinic and hepatic cells. The comparative analysis between normal and actinomycin D segregated nucleoli fixed either with glutaraldehyde-osmium or potassium pyroantimonate facilitates location of the ring-shaped precipitates in the fibrillar centers and the fine dense ones in the pars fibrosa.