Amplification of DNA sequences in Epstein-Barr virus and human immunodeficiency virus using DNA polymerase from Thermus thermophilus

Using thermophilic DNA-polymerase from Thermus thermophilus we have amplified by polymerase chain reaction (PCR) specific DNA sequences of Epstein-Barr virus (EBV) and human immunodeficiency virus (HIV). DNA-polymerase from Thermus thermophilus (the molecular mass of 80 to 86 kDa) differs in its physico-chemical properties from DNA-polymerase from the Thermus acquaticus (the molecular mass of 62 to 68 kDa). To amplify the specific EBV DNA sequence oligonucleotide primers for the virus replicon region (oriP-region) were used. As a result of amplification, a specific 405 b.p. DNA fragment was produced. Primers for the virus Gag region were used for amplification of HIV DNA. The possibility to conduct amplification cycles under two temperature conditions was demonstrated.     

Increase in Athletes’ Functional Capacities via Biological Feedback

The method of active self-regulation of functions on the basis of biological feedback via the electroencephalogram (EEG-BFB) was tested. A relatively short-term EEG-BFB exerts a strong beneficial effect on the functional state of various systems of organs and the human body as a whole.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 3, 2005, pp. 93–99.Original Russian Text Copyright © 2005 by Vysochin, Denisenko, Gordeev.     

A comparative study of the effectiveness of regulatory peptides in acute experimental pancreatitis

The effect of regulatory peptides on the functional activity of pancreatic cells and phagocytic cells of reticuloendothelial system were determined in intact dogs against the background of acute experimental pancreatitis. Assessment of the efficacy of regulatory peptides was made with the aid of scintigraphic studies in gamma chamber using for this purpose colloid 198Au and 75Se-methionine. It was established that introduction of regulatory peptides to dogs leads to inhibition of capture of labeled methionine by pancreatocytes, practically not influencing the elimination of colloid gold from circulation.     

Adaptation ofRhodococcus rhodochrous M8, a producer of acrylamide, to changes in ammonium concentration in the growth medium

The mechanism of adaptation of the acrylamide producing strainRhodococcus rhodochrous M8 to changes in ammonium concentrations in the medium was studied. An increase in the content of ammonium in the medium changed the activity of glutamine synthetase (GS) (EC 6.3.1.2) and glutamine dehydrogenase (GD) (EC 1.4.1.4), the enzymes of ammonium assimilation, as well as the activities of enzymes responsible for nitrile utilization: nitrile hydratase (EC 4.2.1.84) and amidase (EC 3.5.1.4). This also inhibited the activation of GS induced by phosphodiesterase (EC 3.1.4.1 ). Increases in the activities of nitrile hydratase and amidase and resistance of these enzymes to ammonium were observed in mutant ofR. rhodichrous resistant to phosphotricine, an inhibitor of GS. An important role of GS in the mechanism of adaptation is suggested.     

2D format for screening bacterial cells at the throughput of flow cytometry

We present a method for generating gel-based unordered 2D arrays of bacterial cells of a very high density, up to 10(5) cells per mm(2). Bacteria in a suspension are focused into a thin layer when the suspension and a dry gel matrix penetrate each other. Formation of a second gel from gel-forming components contained in the suspension results in immobilization of the cells. The immobilized cells stay alive and can repeatedly divide to produce microcolonies. The method provides for high-throughput screening and massively parallel analysis of individual cells in large populations, as well as for rapid isolation of rare clones.     

Femtosecond pulsed laser ablation to enhance drug delivery across the skin

Laser poration of the skin locally removes its outermost, barrier layer, and thereby provides a route for the diffusion of topically applied drugs. Ideally, no thermal damage would surround the pores created in the skin, as tissue coagulation would be expected to limit drug diffusion. Here, a femtosecond pulsed fiber laser is used to porate mammalian skin ex vivo. This first application of a hollow core negative curvature fiber (HC‐NCF) to convey a femtosecond pulsed, visible laser beam results in reproducible skin poration. The effect of applying ink to the skin surface, prior to ultra‐short pulsed ablation, has been examined and Raman spectroscopy reveals that the least, collateral thermal damage occurs in inked skin. Pre‐application of ink reduces the laser power threshold for poration, an effect attributed to the initiation of plasma formation by thermionic electron emission from the dye in the ink. Poration under these conditions significantly increases the percutaneous permeation of caffeine in vitro. Dye‐enhanced, plasma‐mediated ablation of the skin is therefore a potentially advantageous approach to enhance topical/transdermal drug absorption. The combination of a fiber laser and a HC‐NCF, capable of emitting and delivering femtosecond pulsed, visible light, may permit a compact poration device to be developed.

Using a femtosecond pulsed, visible laser beam to create an array of micropores in dyed mammalian skin, with little collateral, thermal damage, leads to an enhancement in the percutaneous permeation of caffeine in vitro.     

Evaluation of the Contribution of Homologous Recombination in DNA Double-Strand Break Repair in Human Fibroblasts after Exposure to Low and Intermediate Doses of X-ray Radiation

Biology Bulletin - Abstract—Studies of the changes in the number of γH2AX foci (a DNA double-strand break protein-marker), and Rad51 foci (a key homologous recombination protein) were...     

The meadow-field type of tularemia foci in eastern Siberia

The article characterizes a meadow-type focus tularemia, discovered in Zalarinski'i District of Irkutsk Province in 1988. This focus and another similar focus discovered in 1985 at the Krasnoyarsk Territory belong to the meadow type, which makes it possible to regard their presence in Eastern Siberia as an established fact. The main reservoirs and sources of infection in these foci are two species of voles (Microtus gregalis and M. subarvalis).     

Single Protein Molecule Mapping with Magnetic Atomic Force Microscopy

Understanding the structural organization and distribution of proteins in biological cells is of fundamental importance in biomedical research. The use of conventional fluorescent microscopy for this purpose is limited due to its relatively low spatial resolution compared to the size of a single protein molecule. Atomic force microscopy (AFM), on the other hand, allows one to achieve single-protein resolution by scanning the cell surface using a specialized ligand-coated AFM tip. However, because this method relies on short-range interactions, it is limited to the detection of binding sites that are directly accessible to the AFM tip. We developed a method based on magnetic (long-range) interactions and applied it to investigate the structural organization and distribution of endothelin receptors on the surface of smooth muscle cells. Endothelin receptors were labeled with 50-nm superparamagnetic microbeads and then imaged with magnetic AFM. Considering its high spatial resolution and ability to “see” magnetically labeled proteins at a distance of up to 150 nm, this approach may become an important tool for investigating the dynamics of individual proteins both on the cell membrane and in the submembrane space.