Measurement performance assessment for the ITER CXRS Edge diagnostic system.

Measurement performance assessment has been carried out for the latest design of the ITER Charge Exchange Recombination Spectroscopy (CXRS) Edge diagnostic system. Several plasma scenarios, covering all expected baseline operation regimes for ITER, were used. Various impurity (He, Be, C, and Ne) concentrations for the system whole spatial range (0.5 < r/a < 1.0) were considered. Statistical errors for the measurements of low-Z impurity temperature, density, and rotation velocity were calculated. Other non-statistical error sources were reviewed, including the presence of wall reflections, effects on the active charge-exchange line shape, calibration, and positioning uncertainties. Minimal impurity concentrations, allowing measurements with required accuracy, were obtained. It was shown that the CXRS Edge system will be able to measure primary plasma parameters with required accuracy, space, and time resolution.

Charge exchange recombination spectroscopy on the T-10 tokamak.

The charge exchange recombination spectroscopy (CXRS) diagnostics on the T-10 tokamak is described. The system is based on a diagnostic neutral beam and includes three high etendue spectrometers designed for the ITER edge CXRS system. A combined two-channel spectrometer is developed for simultaneous measurements of two beam-induced spectral lines using the same lines of sight. A basic element of the combined spectrometer is a transmitting holographic grating designed for the narrow spectral region 5291 ± 100 Å. The whole CXRS system provides simultaneous measurements of two CXRS impurity spectra and Hα beam line. Ion temperature measurements are routinely provided using the C(6+) CXRS spectral line 5291 Å. Simultaneous measurements of carbon densities and one more impurity (oxygen, helium, lithium etc.) are carried out. Two light collecting systems with 9 lines of sight in each system are used in the diagnostics. Spatial resolution is up to 2.5 cm and temporal resolution of 1 ms is defined by the diagnostic neutral beam diameter and pulse duration, respectively. Experimental results are shown to demonstrate a wide range of the CXRS diagnostic capabilities on T-10 for investigation of impurity transport processes in tokamak plasma. Developed diagnostics provides necessary experimental data for studying of plasma electric fields, heat and particle transport processes, and for investigation of geodesic acoustic modes.

Long-term thyrotropin-suppressive therapy with levothyroxine impairs small and large artery elasticity and increases left ventricular mass in patients with thyroid carcinoma.

BACKGROUND: Exogenous subclinical hyperthyroidism, caused by long-term thyrotropin (TSH)-suppressive treatment with levothyroxine (LT(4)), is associated with several cardiovascular abnormalities. In order to assess the effect of long-term thyroid hormone-suppressive therapy on the blood vessels and myocardium, we determined the arterial elasticity, using the pulse wave contour analysis. METHODS AND RESULTS: Twenty-six athyreotic patients receiving TSH-suppressive LT(4) therapy for periods ranging from 3 to 21 years at a mean daily dose of 2.25 +/- 0.5 microg/kg per day were included in the study. Twenty six age- and gender-matched healthy subjects served as controls. Arterial elasticity of large and small arteries was evaluated using pulse wave contour analysis method (HDI CR 200, Eagen, MN). Cardiac structure was assessed by two-dimensional echocardiography. We found decreased large artery elasticity in subclinical hyperthyroidism (sHT) patients compared to controls (14.14 +/- 3.38 versus 10.53 +/- 2.43 L/mm Hg x 100, p < 0.000). Small artery elasticity was also lower in patients than in controls (5.42 +/- 1.82 versus 4.30 +/- 1.75 mL/mm Hg x 100, p < 0.056). The echocardiographic data showed significantly increased left ventricular (LV) mass index (101.90 +/- 18.61 versus 88.03 +/- 22.01 g/m(2), p < 0.049) and interventricular septum thickness (10.61 +/- 1.46 versus 9.11 +/- 1.13 mm, p < 0.002) in LT(4)-treated patients compared to controls. CONCLUSIONS: We found impaired vascular elasticity of large and small arteries and increased LV mass in patients receiving long-term TSH-suppressive therapy with LT(4).

[Regulation of human oct-1 gene transcription involves two promotors]. / Reguliatsiia transkriptsii gena oct-1 cheloveka s uchastiem dvukh promotorov.

Transcription initiation of human Oct-1 transcription factor-encoding gene involves two promoters, 1U and 1L, located at a substantial distance (about 100 kb) apart. The structure of these promoters and the adjacent sequences is different. Specifically, the 1U sequence is GC-rich, while the 1L sequence is AT-rich. Correspondingly, more than 25 GC-rich Sp1 cis-elements were localized within the 1U region, while in the 1L sequence nearly equal amount of homeo-specific NTAATNN sites along with two ATGCAAAT octamers were found. Analysis of transfection of recombinant plasmids, carrying the promoter fragments with or without enhancer indicated that expression from the 1L promoter was tissue-specific. In nonlymphoid HEK293 cells efficiency of transcription from the 1U promoter was several times higher than that from the 1L promoter. Another expression pattern was observed at transfection of the same constructs into Raji lymphoid cells. In this case the level of transcription from the L promoter (fragment L2) at the presence of external enhancer was higher than that from the fragments containing the 1U promoter. It was shown that the distal regions of 1U and 1L were capable of silencing activity. In Raji cells enhancer completely overcomes the activity of U silencer, but only partly overcomes the activity of L silencer. Our data on the interaction of two promoters with the enhancer and silencer in different cell types point to fine tissue-specific regulation of the oct-1 gene expression, especially in lymphatic cells.

[Targeting the gene for platelet-derived growth factor A-chain (PDGF-A) and preparation of chimeric mice with a "knockout" genome]. / Targeting gena A-tsepi trombotsitarnogo faktora rosta (PDGF-A) i poluchenie khimernoi myshi s "nokautirovannym" genom.

A vector was selected for homologous recombination to generate mouse embryonic stem cell clones with disrupted platelet-derived growth factor A (PDGF-A) chain gene. A chimeric mouse with targeted PDGF-A gene has been created.

[Expression of the gene for transforming growth factor type alpha, transferred into A431 cells by a recombinant retroviral vector]. / Ekspressiia gena transformiruiushchego faktora rosta tipa alpha, perenesennogo rekombinantnym retrovirusnym vektorom v kletki A431.

Cells of human epidermoid carcinoma A431 were used for obtaining of the cell line constantly expressing TGF-alpha. Recombinant virions were obtained by introducing the proviral DNA into PA317 cells by means of electrotransfection. A protein with the EGF-competing activity was found in a conditioned media of the chosen clone A431/1522-4. The concentration of this protein was several times higher than in a conditioned media of wild type A431 cells. By means of electrophoresis, isoelectric focusing, and immunochemical analysis it was shown that the protein is TGF-alpha. Similarly to EGF, the extracted TGF-alpha entirely displaced 125I-EGF specifically bound to receptor. TGF-alpha produced by the A431/1522 cells also stimulated autophosphorylation of the EGF receptor.

Electroporation and electrophoretic DNA transfer into cells. The effect of DNA interaction with electropores.

It has been shown recently that electrically induced DNA transfer into cells is a fast vectorial process with the same direction as DNA electrophoresis in an external electric field (Klenchin, V. A., S. I. Sukharev, S. M. Serov, L. V. Chernomordik, and Y. A. Chizmadzhev. 1991. Biophys. J. 60:804-811). Here we describe the effect of DNA interaction with membrane electropores and provide additional evidences for the key role of DNA electrophoresis in cell electrotransfection. The assay of electrically induced uptake of fluorescent dextrans (FDs) by cells shows that the presence of DNA in the medium during electroporation leads to a sharp increase in membrane permeability to FDs of M(r) < 20,000. The permeability increases with DNA concentration and the effect is seen even if FD is added to the cell suspension a few minutes after pulse application. The longer the DNA fragment, the greater the increase in permeability. The use of a two-pulse technique allows us to separate two effects provided by a pulsed electric field: membrane electroporation and DNA electrophoresis. The first pulse (6 kV/cm, 10 microseconds) creates pores efficiently, whereas transfection efficiency (TE) is low. The second pulse of much lower amplitude, but substantially longer (0.2 kV/cm, 10 ms), does not cause poration and transfection by itself but enhances TE by about one order of magnitude. In two-pulse experiments, TE rises monotonously with the increase of the second pulse duration. By varying the delay duration between the two pulses, we estimate the lifetime of electropores (which are DNA-permeable in conditions of low electric field) as tens of seconds. The data suggest that the mechanism of cell electrotransfection is underlain by electrophoretic movement of DNA through membrane pores, the size of which is determined by interaction with DNA in an electric field.

Electrically induced DNA uptake by cells is a fast process involving DNA electrophoresis.

Simian Cos-1 cells were transfected electrically with the plasmid pCH110 carrying the beta-galactosidase gene. The efficiency of transfection was determined by a transient expression of this gene. When the plasmid was introduced into a cell suspension 2 s after pulse application, the transfection efficiency was shown to be less than 1% as compared with a prepulse addition of DNA. Addition of DNAase to suspension immediately after a pulse did not decrease transfection efficiency, thus the time of DNA translocation was estimated to be less than 3 s. The use of electric treatment medium, in which the postpulse colloid-osmotic cell swelling was prevented, did not affect the transfection efficiency. These results contradict both assumptions of free DNA diffusion into cell through the long-lived pores and of involvement of osmotic effects in DNA translocation. Transfection of cells in monolayer on a porous film allowed creation of the spatial asymmetry of cell-plasmid interaction along the direction of electric field applied. A pulse with a polarity inducing DNA electrophoresis toward the cells resulted in the 10-fold excess of transfection efficiency compared with a pulse with reverse polarity. Ficoll (10%) which increases medium viscosity or Mg2+ ions (10 mM) which decrease the effective charge of DNA, both reduced transfection efficiency 2-3-fold. These results prove a significant role of DNA electrophoresis in the phenomenon considered. The permeability of cell membranes for an indifferent dye was shown to increase noticeably if the cells were pulsed in the presence of DNA. This indicates a possible interaction of DNA translocated with the pores in an electric field, that results in pore expansion.

[An immunochemical study of M-HeLa cells as producers of human placental alkaline phosphatase]. / Immunokhimicheskoe issledovanie kletok linii M-HeLa kak produtsentov platsentarnoi shchelochnoi fosfatazy cheloveka.

While analyzing M-HeLa cells by IFA technique secretory and membrane-bound forms of human placental alkaline phosphatase (HPAP) were detected. Activity of secretory HPAP increased if cell density and incubation time were increased too. After short influence of heat shock (15 min at 42 degrees C) activity of secretory HPAP increased for 45% and intracellular HPAP 3 for 37%. It is proposed that HPAP take part in organization of first response to heat shock and support cellular thermotolerance.

[The cellular mechanisms of the physiological action of iodobromide mineral waters]. / Nekotorye kletochnye mekhanizmy fiziologicheskogo deistviia iodobromnykh mineral'nykh vod.

The experiments on edible frogs have revealed the relationship between the effect of sodium chloride, skin potential difference and micro-components iodide and bromide present in the solution. The results obtained furnish the additional information on the synergistic action of mineral water iodide and bromide on the body. Iodide ions were found to act mainly through inhibition of sodium channels of cellular membranes, while bromide ions are likely to affect Na, K-ATPase.

[Mechanisms of the action of hypertonic solutions on the ionic permeability of human skin]. / Nekotorye mekhanizmy deistviia gipertonicheskikh rastvorov na ionnuiu pronitsaemost kozhi cheloveka.

For human skin transcutaneous transport of I ions in vitro depends on sodium chloride-iodide concentration relations in mineral water, whereas such transport for Br ions in mainly determined by absolute concentration of sodium chloride. Optimal proportions of the salts have been specified for I and Br ions transcutaneous transport in definite concentration range. An unknown feature of the mechanism of action of hypertonic salt solutions on ionic skin permeability has been identified. The results are analyzed from the point of view of the ion pairs conception.

[Neurophysiological and mathematical optimization of the parameters for electrostimulation of the muscles with sinusoidal modulated currents in patients with poststroke paralysis]. / Neirofiziologicheskaia i matematicheskaia optimizatsiia parametrov élektrostimuliatsii myshts sinusoidal'nymi modulirovannymi tokami u bol'nykh s postinsul'tnymi parezami.

Patients with poststroke pareses exposed to different frequencies of stimulating current (sinusoidal modulated currents--SMC) were studied for changes in the H-reflex amplitude (by the H max/M max index). The authors identified a number of clinical signs of stroke predisposing to a definite regimen of electrostimulation. Mathematical processing of the clinical findings has helped to develop a technique of the differential use of muscle electrostimulation by SMC in patients with poststroke hemipareses.

[Molecular cloning of MuLV proviruses integrated into the genome of mouse erythroleukemia cells. I. Characteristics of endogenous proviruses]. / Molekuliarnoe klonirovanie provirusov MuLV, integrirovannykh v genom myshinykh éritroleikoznykh kletok. I. Kharakteristika provirusov éndogennogo proiskhozhdeniia.

The library of genes was obtained from erythroleukemic AKR cells (C-1), that were maintained as suspension culture. Thirty four clones that had homology with 60-70S RNA of Rauscher Leukemia virus (RLV) were separated from this library. The restriction mapping was carried out with 14 clones, that contained most extensive proviral sequences. One clone (107) contains proviral sequences that are derived from one of the components of the RLV complex. The other 13 clones contain sequences of endogenous xenotropic viruses. The endogenous retroviral sequences obtained differ in restrictive maps from proviruses of ecotropic and xenotropic infectious endogenous MuLV and, apparently, might be attributed as non-inducible infectious xenotropic MuLV of class III. Some of the cloned retroviral sequences had symmetrical structure, that is typical for integrated proviruses, i. e. these sequences were separated from flanking cellular ones by long terminal repeats. All investigated retroviral sequences are deletion mutants of MuLV proviruses. It was shown that the inner regions of proviruses diverged more than the long terminal repeats. The expression of the main inner MuLV polypeptide (p30) was detected in NIH 3T3 cells, transfected with DNA of some clones.