Calculation of the Biological Efficiency of the Proton Component from 14.8 MeV Neutron Irradiation in Computational Biology with Help of Video Cards

Bulletin of Experimental Biology and Medicine - Fast neutron therapy, which previously has demonstrated effective results, but along with a large number of complications, can again be considered a...     

Regenerative medicine of pancreatic islets

The pancreas became one of the first objects of regenerative medicine,since other possibilities of dealing with the pancreatic endocrine insufficiency were clearly exhausted.The number of people living with diabetes mellitus is currently approaching half a billion,hence the crucial relevance of new methods to stimulate regeneration of the insulin-secreting β-cells of the islets of Langerhans.Natural restrictions on the islet regeneration are very tight;nevertheless,the islets are capable of physiological regeneration via β-cell self-replication,direct differentiation of multipotent progenitor cells and spontaneous α-to or δ-to β-cell conversion(trans-differentiation).The existing preclinical models of β-cell dysfunction or ablation(induced surgically,chemically or genetically) have significantly expanded our understanding of reparative regeneration of the islets and possible ways of its stimulation The ultimate goal,sufficient level of functional activity of β-cells or their substitutes can be achieved by two prospective broad strategies β-cell replacement and β-cell regeneration.The "regeneration" strategy aims to maintain a preserved population of β-cells through in situ exposure to biologically active substances that improve β-cell survival,replication and insulin secretion,or to evoke the intrinsic adaptive mechanisms triggering the spontaneous non-β-to β-cell conversion.The "replacement" strategy implies transplantation of β-cells(as non-disintegrated pancreatic material or isolated donor islets) or β-like cells obtained ex vivo from progenitors or mature somatic cells(for example,hepatocytes or a-cells) under the action of small-molecule inducers or by genetic modification.We believe that the huge volume of experimental and clinical studies will finally allow a safe and effective solution to a seemingly simple goal-restoration of the functionally activeβ-cells, the innermost hope of millions of people globally.     

Synthesis and antibacterial properties of hydrazonothiazolyl derivatives of saturated 2,4,4-substituted butanolides

A method has been developed for the synthesis of new heterocyclic compounds containing γ-butanolide fragments. The antibacterial properties of the obtained compounds have been investigated. The tested compounds exhibit moderate antibacterial activity. Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 43, No. 3, pp. 22–25, March, 2009.     

Synthesis and conversions of polyhedral compounds: 28. Synthesis and psychotropic activity of some 1,3-diazaadamantane derivatives

The anticonvulsant and tranquilizer properties of some new derivatives of 1,3-diazaadamantane have been investigated. It is established that some of the synthesized compounds prevent corazole-induced convulsions in mice in a dose range of 18–75 mg-kg. The study of the influence of these compounds on the behavior of rats under open-field test conditions revealed a pronounced tranquilizer action. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 11, pp. 25–26, November, 2007.     

Extracellular portions of HLA antigens are not compact globulae

Membranes of human spleen cells were hydrolyzed by papain and the extracellular portions of HLA antigen molecules isolated by monoclonal antibodies fixed on Sepharose. The isolated proteins were spin-labeled by TEMPO-dichlorotriazine. The values of rotational correlation times (tau) of spin-labeled proteins were calculated using dependencies of magnetic parameters found from ESR spectra vs viscosity at constant temperature. The tau-values were equal to 8 nsec for class I molecules and 14 nsec for class II molecules. These values were significantly lower than those predicted for a rigid sphere with dimensions equal to the extracellular portions of HLA molecules (20 nsec). This fact suggests the existence of flexibility in poly-functional HLA molecules, which seems to be important for their biological activity. In this respect, extracellular portions of HLA molecules resemble flexible Fc fragments (tau = 12 nsec) and differ from rigid Fab fragments (tau = 20 nsec) of immunoglobulins G. The rotation of the oligosaccharide chains attached to HLA molecules is restricted.