Analysis of RNA cleavage by RNA polymerases from Escherichia coli and Deinococcus radiodurans.

RNA polymerase can both synthesize and cleave RNA. Both reactions occur at the same catalytic center containing two magnesium ions bound to three aspartic acid residues of the absolutely conserved NADFDGD motif of the RNA polymerase beta subunit. We have demonstrated that RNA polymerase from Deinococcus radiodurans possesses much higher rate of intrinsic RNA cleavage than RNA polymerase from Escherichia coli (the difference in the rates is about 15-fold at 20 degrees C). However, these RNA polymerases do not differ in the rates of RNA synthesis. Comparison of the RNA polymerase sequences adjacent to the NADFDGD motif reveals the only amino acid substitution in this region (Glu751 in D. radiodurans vs. Ala455 in E. coli), which is localized in the secondary enzyme channel and can potentially affect the rate of RNA cleavage. Introduction of the corresponding substitution in the E. coli RNA polymerase leads to a slight (about 2-3-fold) increase in the cleavage rate, but does not affect RNA synthesis. Thus, the difference in the RNA cleavage rates between E. coli and D. radiodurans RNA polymerases is likely determined by multiple amino acid substitutions, which do not affect the rate of RNA synthesis and are localized in several regions of the active center.

Lineage-specific amino acid substitutions in region 2 of the RNA polymerase sigma subunit affect the temperature of promoter opening.

Highly conserved amino acid residues in region 2 of the RNA polymerase sigma subunit are known to participate in promoter recognition and opening. We demonstrated that nonconserved residues in this region collectively determine lineage-specific differences in the temperature of promoter opening.

[Electrical and magnetic fields of the elementary bioelectric generator in the bounded anisotropic myocardium]. / Elektricheskoe i magnitnoe polia élementarnogo bioélektricheskogo generatora v anizotropnom ogranichennom miokarde.

Using the equations of electrodynamics of stationary currents, relationships were derived for calculating the characteristics of electric and magnetic fields of an elementary (dipole) bioelectric generator in a heterogeneous medium consisting of two regions namely, an anisotropic conducting region corresponding to the excitable myocardium tissue and an isotropic conducting or dielectric region corresponding to the space outside the myocardium where the measurement is made. The shape of distributions of the electric potential and magnetic induction at the myocardium surface was determined, and the effect of anisotropy on these distributions was estimate. Formulas for the identification of the local excited zone within the myocardium from electric and magnetic measurements outside the excitable tissue or on its surface were obtained.

[Electric and magnetic fields of the closed depolarization front in the anisotropic myocardium]. / Elektricheskoe i magnitnoe pole zamknutogo fronta depoliarizatsii v anizotropnom miokarde]

On the basis of the bidomain model of anisotropic myocardium, mathematical relationships for calculating the characteristics of the extracellular electric and magnetic fields outside a closed or open depolarization front were derived on the assumption that the generator and fields are axially symmetric with respect to the longitudinal direction of the fibres making up the excitable tissue. The spatial configuration of the fields was determined and quantitative estimates were obtained for the electric potential and magnetic induction caused solely by the macroscopic anisotropy of the myocardium tissue as a volume conductor.

[The entomological and acarological situation in Nizhegorod Province]. / Entomologicheskaia i akarologicheskaia situatsiia v Nizhnegorodskoi oblasti.

Ixodes, persulcatus, I. ricinus, D. reticulatus, D. marginatus, H. concinna were recorded in different regional environmental regions. The northern districts of the region are endemic for tick-borne encephalitis (TBE) and Ixodes tick-borne borreliosis (ITBB). The infection of ticks with TBE virus is 0.25%, that with Borrelia is 10.3% of the total number of the examinees. In 1997 TBE and TTBB morbidity rates were 1.91 and 2.0 per 100,000, respectively. Data on the phenology of prevailing Anopheles messeae are given. Human malaria contamination may take 99-102 days (the first ten days of June to the second ten days of September). The large size of malaria mosquitoes and the presence of imported cases of malaria make it possible to deteriorate the malaria epidemiological situation. The larvicidal activity of a preparation derived from shepherd's-purse (Capsella bursa pastoris) [correction of caseweed (Bursae pastoris)] was tested. 80-85% deaths of larvae of second-third ages occurred 48 hours after treatment with the preparation, 1 kg/ha.

[An elementary bioelectrical generator of the anisotropic homogeneous myocardium and its extracellular field]. / Elementarnyi bioelektricheskii generator anizotropnogo odnorodnogo miokarda i ego vnekletochnoe pole.

On the basis of the bidomain model that takes into account the electric anisotropy of body tissues, analytical relationships were developed for calculating the characteristics of electric and magnetic fields produced by an elementary (dipole) bioelectric generator that arises in the electrogenic excitable tissue of the myocardium. The errors in the identification of intensity and location of the bioelectric generator in the myocardium were estimated from the measurements of its external fields (noninvasive identification of the excited region) using approximate methods based on isotropic models of the physical medium.

[A model of spherical quasi-epicardium for mapping of the electrical potential of the heart]. / Model' sfericheskogo kvasiépikarda dlia otobrazheniia élektricheskogo potentsiala serdtsa.

Possibility of determination of the heart electric potential maps on the spherical quasiepicardium from the body surface potentials measured by means of multiple leads, is estimated. The simplified models of ventricular depolarization electric generator considered in this study, consist of sets of uniform double layers representing basic configurations of the true electric generator of the heart, while allowing an analytical calculation of the multipole components, as well as potential of the generator. The contribution of the generator multipole components to the potential on the spherical quasiepicardium is evaluated. The results of the study show that it is reasonable to use the multipole components up to the 3rd order for noninvasive mapping of the potential on the spherical quasiepicardium with the radius which provides tangential touching of the quasiepicardium with the precordium surface. Because of bringing the potential observation region nearer to the generator and improving concentricity of this region with respect to the generator, the quasiepicardium mapping technique allows revealing much more complicated generator configurations than those found out by straightforward estimation of the potential measured on the chest surface, thereby facilitating more accurate noninvasive recognition of the heart electrophysiological state.

Decarto technique in long-term observation of patients treated for primary pulmonary hypertension.

Techniques for noninvasive observation of heart states play an important part in experimental and therapeutic cardiology. The objective of this work is to describe a new method for intelligible pictorial representation of data acquired by an orthogonal electrocardiographic lead system and demonstration of possibilities of this method in estimating the results of longterm treatment for a cardiac disease. The method used, dipole electrocardiotopography (DECARTO), provides a set of maps (decartograms) that depict in an explicit form the instantaneous, as well as integral electrophysiological properties of the heart during the excitation cycle. The observed group of patients contained 10 females and 2 males with primary pulmonary hypertension. It was found that in all but one cases tested, the features of the maps strongly correlated with the results of the other diagnostical methods and clinical findings. The trends to improvement (6 cases), stabilization (4 cases), or deterioration (1 case) of the heart state were clearly indicated. In one case, however, the interpretation of the decartograms was ambiguous. The advantage of the DECARTO technique lays in clearness of data representation for visual analysis and facilitation of electrophysiological and anatomical interpretation of the data. (Fig. 6, Ref. 2)

[Labor migration to Russia from nearby countries]. / Trudovaya migratsiya v Rossiyu iz stran blizhnego zarubezh'ya.

PIP: According to official data the unemployment rate in the Russian Federation at the end of the first half of 1995 reached 5.7 million people, or 7.6% of the economically active population. At the present time [1996] the proportion of potentially unemployed people ranges from 13% to 17% of the economically active population. During 1993-95, in the whole economy of Russia, the number of vacancies fluctuated between 320,000 and 400,000. Moreover, in the first quarter of 1995 an increase of manpower needs by 14% was observed compared to the first quarter of 1994. In the first half of 1995 the manpower needs increased to 311,000-400,000 people, or 43.1%. As far as the regional distribution of available jobs was concerned, one-fifth of them was located in the Urals and western Siberia and about one-third in the central region. In order to protect the labor market for Russian natives, in December 1993 a presidential decree was issued. At the end of 1994 the number of foreign workers in Russia numbered 128,999 people, of which 73,695 (58.9%) came from adjacent countries bordering Russia. Experts ascertained that these foreign workers provided higher qualifications: 47.2% were better qualified than the local work force, 75% were more productive, and 83.2% were more disciplined. The labor migration in Russia during the 1990s will depend on the demographic and socioeconomic changes in the newly independent states of the former Soviet Union and the composition of the labor market, as well as measures taken in Russia concerning immigration policy. It is estimated that in the coming years the annual number of foreign workers would equal 110,000-130,000 people, and if quotas are set up by mutual agreement the number could grow two- to three-fold compared to the figure of 1994.^ieng

[The functional and sonographic parallels in chronic pancreatitis]. / Funktsional'no-sonograficheskie paralleli pri khronicheskom pankreatite.

Ultrasonic histogramme was studied in 35 patients with chronic pancreatitis and 20 donors, taken in the area of the head and body of the pancreas, as were levels of immunoreactive trypsin--fasting and after standard food load,--and C-peptide in blood serum on an empty stomach. To increase informative value and specificity of ultrasonic and radioimmunologic investigations an index has been suggested, based on the findings from histogramme and radioimmunity analysis.

[2 outbreaks of trichinelliasis in Rostov Province]. / Dve vspyshki trikhinelleza v Rostovskoi oblasti.

Two epidemiologically unrelated outbreaks of trichinellosis were registered in Rostov Province in the November and December of 1984 with 16 patients in the Salsk District and 20 patients in Rostov-on-Don. The course of the disease was characterized by 6-20% of severe and 31-45% moderate forms, respectively. The source of the infection was pork that had not been controlled for Trichinella spiralis. Late diagnosis and inadequate treatment in one case led to a fatal outcome. Economic losses accounted for 490,000 rubles (as of 1985). In spite of energetic prophylaxis measures, the situation in the Rostov Province continues to be serious. In 1989-1992, eighteen cases of trichinellosis were registered in the Salsk District again.

[Embovin efficacy and tolerance in the treatment of patients with intestinal nematode infections]. / Effektivnost' i perenosimost' émbovina pri lechenii bol'nykh kishechnymi nematodozami.

The efficacy and tolerance of embovin, a new anthelminthic manufactured in Russia, was studied in 60 patients with nematodiases. The results evidence its high efficacy in ankylostomiasis (100%), enterobiasis (100%), and ascariasis (90 +/- 6.4%). The drug was well tolerated in all the cases. No adverse effects on the liver, pancreas, kidneys, as well as on the peripheral blood and urine composition were detected. This recommends embovin for wide use in medical practice.