Oxidation in vivo of glucose, palmitate, alanine and leucine in the pig during the neonatal period

Determination of 14CO2 content in expired air after the intravenous injection of energetic substrates marked by the radioactive carbon to the pigs showed that the oxidative intensity of these substrates decreases in the series: [6-14C]glucose greater than [1-14C] alanine greater than [1-14C]leucine greater than [1-14C]glucose. The oxidation intensity of all substrates under study except for [1-14C]palmitate in the organism of one-day satisfied pigs is considerably higher, than during the first two hours after their birth. The starvation of pigs during the first 24 hours increases the oxidation of both investigated amino acid and [1-14C]-palmitate in tissues of their organism with a decrease in the metabolic intensity of [6-14C] and [1-14C]glucose.     

Inhibition of Yersinia protein tyrosine phosphatase by phosphonate derivatives of calixarenes

Inhibition of Yersinia protein tyrosine phosphatase by calix[4]arene mono-, bis-, and tetrakis(methylenebisphosphonic) acids as well as calix[4]arene and thiacalix[4]arene tetrakis(methylphosphonic) acids have been investigated. The kinetic studies revealed that some compounds in this class are potent competitive inhibitors of Yersinia PTP with inhibition constants in the low micromolar range. The binding modes of macrocyclic phosphonate derivatives in the enzyme active center have been explained using computational docking approach. The results obtained indicate that calix[4]arenes are promising scaffolds for the development of inhibitors of Yersinia PTP.     

Sustained Photosynthetic Performance of Coffea spp. under Long-Term Enhanced [CO2]

Coffee is one of the world’s most traded agricultural products. Modeling studies have predicted that climate change will have a strong impact on the suitability of current cultivation areas, but these studies have not anticipated possible mitigating effects of the elevated atmospheric [CO₂] because no information exists for the coffee plant. Potted plants from two genotypes of Coffea arabica and one of C. canephora were grown under controlled conditions of irradiance (800 μmol m^-2 s^-1), RH (75%) and 380 or 700 μL CO₂ L^-1 for 1 year, without water, nutrient or root development restrictions. In all genotypes, the high [CO₂] treatment promoted opposite trends for stomatal density and size, which decreased and increased, respectively. Regardless of the genotype or the growth [CO₂], the net rate of CO₂ assimilation increased (34-49%) when measured at 700 than at 380 μL CO₂ L^-1. This result, together with the almost unchanged stomatal conductance, led to an instantaneous water use efficiency increase. The results also showed a reinforcement of photosynthetic (and respiratory) components, namely thylakoid electron transport and the activities of RuBisCo, ribulose 5-phosphate kinase, malate dehydrogenase and pyruvate kinase, what may have contributed to the enhancements in the maximum rates of electron transport, carboxylation and photosynthetic capacity under elevated [CO₂], although these responses were genotype dependent. The photosystem II efficiency, energy driven to photochemical events, non-structural carbohydrates, photosynthetic pigment and membrane permeability did not respond to [CO₂] supply. Some alterations in total fatty acid content and the unsaturation level of the chloroplast membranes were noted but, apparently, did not affect photosynthetic functioning. Despite some differences among the genotypes, no clear species-dependent responses to elevated [CO₂] were observed. Overall, as no apparent sign of photosynthetic down-regulation was found, our data suggest that Coffea spp. plants may successfully cope with high [CO₂] under the present experimental conditions.     

A 3D-Video-Based Computerized Analysis of Social and Sexual Interactions in Rats

A large number of studies have analyzed social and sexual interactions between rodents in relation to neural activity. Computerized video analysis has been successfully used to detect numerous behaviors quickly and objectively; however, to date only 2D video recording has been used, which cannot determine the 3D locations of animals and encounters difficulties in tracking animals when they are overlapping, e.g., when mounting. To overcome these limitations, we developed a novel 3D video analysis system for examining social and sexual interactions in rats. A 3D image was reconstructed by integrating images captured by multiple depth cameras at different viewpoints. The 3D positions of body parts of the rats were then estimated by fitting skeleton models of the rats to the 3D images using a physics-based fitting algorithm, and various behaviors were recognized based on the spatio-temporal patterns of the 3D movements of the body parts. Comparisons between the data collected by the 3D system and those by visual inspection indicated that this system could precisely estimate the 3D positions of body parts for 2 rats during social and sexual interactions with few manual interventions, and could compute the traces of the 2 animals even during mounting. We then analyzed the effects of AM-251 (a cannabinoid CB1 receptor antagonist) on male rat sexual behavior, and found that AM-251 decreased movements and trunk height before sexual behavior, but increased the duration of head-head contact during sexual behavior. These results demonstrate that the use of this 3D system in behavioral studies could open the door to new approaches for investigating the neuroscience of social and sexual behavior.     

Changes in functional state of the low-molecular G-proteins of platelets in type 1 diabetes mellitus

Platelets from healthy donors and insuline dependent patients with type 1 diabetes mellitus were examined for proteins specifically interacting in vitro with GST-fused constitutively active (Val12) forms of small GTPases of Rac, Rho and Cdc42. Differential changes in pattern of proteins which bind to these G-proteins in diabetic platelets have been revealed. Obtained results suggest that signalling pathways mediated by Rho GTPases are altered under type I diabetes mellitus. Such changes of actin cytoskeleton regulation may contribute to the higher level of platelet aggregation, which prove to be the etiological background of the late diabetes complications.     

Thrombin inhibitors built on an azaphenylalanine scaffold

A series of azaphenylalanine derivatives were investigated as novel thrombin inhibitors based on the prodrug principle. By systematic structural modifications we have identified optimal groups for this series that led us to potent inhibitors of thrombin incorporating the benzamidine fragment at the P1 position, and their potentially orally active benzamidoxime prodrugs. The binding modes in the thrombin active site of two representative compounds were identified by X-ray crystallographic analysis.     

Basic measures for prevention of the epidemiological consequences of a natural disaster in the North Caucasus in 2002

The system of organizational and prophylactic measures, carried out with a view to prevent epidemiological aggravations in connection with the natural calamity in the Southern Federal District of the Russian Federation in 2003, is described. Proposals on the improvement of the system of preventive measures, including the monitoring of the epidemiological, sanitary and hygienic situation, personnel training, technical provision, the cooperation of different services and departments, capable of ensuring the liquidation of the consequences of emergency situations of the natural character, are made.     

Kinetic and mechanism of interaction of L-cysteine with alkaline phosphatase from calf intestines

The effect of L-cysteine on activity of hydrophobic forms of calf intestine alkaline phosphatase was investigated. Apparent inhibition constants for mixed type inhibition have been determined. The kinetic results allow supposing that the mechanism of equilibrium establishment between the inhibitor and enzyme involves the initial rapid formation of intermediate complex and a subsequent slower step leading to its stabilization in the substrate binding site. The microscopic rate constants for slow step of interaction of L-cysteine with alkaline phosphatase have been calculated. Effect of pH on apparent inhibition constants and kinetic parameters for enzymatic reaction in the presence of L-cysteine was analysed.