Prevalence of gastroesophageal reflux disease in Moscow.

Limited data exist to determine the prevalence and clinical spectrum of gastroesophageal reflux disease (GERD) in the Russian population, which might be different from those in Western countries. This study was performed in Moscow on randomized 1065 adults aged ≥ 15 years. A validated reflux questionnaire comprising 72 questions and an additional 29 sub-questions were used. The questions assessed (heartburn and regurgitation) and related (dyspepsia, dysphagia, odynophagia and chest pain) symptoms, the triggering factors of these symptoms, family history and data on demographic and socioeconomic features. GERD was defined as heartburn and/or regurgitation once a week or common. Of the 1065 participants, 42.1% were male and 57.9% were female. The prevalences of frequent and occasional symptoms were 17.6 and 22.1% for heartburn and 17.5 and 21.8% for regurgitation, respectively, over the last 12 months. The prevalence of GERD was found to be 23.6%. The rate of GERD was significantly higher in females than in males (15.4 vs. 29.5%, P < 0.001) and significantly increased as the age of the participants increased (P = 0.011). GERD was present in 20.4% of smokers, 24.2% of coffee drinkers, 21.5% of alcohol consumers and 45.9% of stressed participants. Although the rate of alcohol consumers was lower in those with GERD compared with those without GERD, the rate of coffee drinkers and stressed participants was higher among those with GERD. The rate of additional symptoms was higher even in participants complaining of regurgitation/heartburn rarely, compared with those without complaints. Using the same questionnaire, which makes it possible to compare the present results with those from different countries, we found the prevalence of GERD in Moscow to be 23.6%, one of highest in the Western populations. The rates of heartburn and regurgitation were found to be similar, which constitutes a different result than has been found in similar studies. Additional symptoms should be assessed, in all GERD patients even in the presence of rare complaints of regurgitation/heartburn.

High-3He Plume Origin and Temporal-Spatial Evolution of the Siberian Flood Basalts.

An olivine nephelinite from the lower part of a thick alkalic ultrabasic and mafic sequence of volcanic rocks of the northeastern part of the Siberian flood basalt province (SFBP) yielded a (40)Ar/(39)Ar plateau age of 253.3 +/- 2.6 million years, distinctly older than the main tholeiitic pulse of the SFBP at 250.0 million years. Olivine phenocrysts of this rock showed (3)He/(4)He ratios up to 12.7 times the atmospheric ratio; these values suggest a lower mantle plume origin. The neodymium and strontium isotopes, rare earth element concentration patterns, and cerium/lead ratios of the associated rocks were also consistent with their derivation from a near-chondritic, primitive plume. Geochemical data from the 250-million-year-old volcanic rocks higher up in the sequence indicate interaction of this high-(3)He SFBP plume with a suboceanic-type upper mantle beneath Siberia.

Behaviour of normal and neoplastic rat cells on grooved substrates.

The distribution and shape of rat cells cultivated on plastic surfaces containing cylindrical areas of various radii and grooves of various depths were studied. Normal embryo cells and two lines of neoplastic cells (LW13K2 and RsK4) were used. The nuclear shape, orientation of the nuclei and migration of cells from the bottom of the grooves were assessed by quantitative methods. All characteristics of the behaviour of both neoplastic cell lines on the grooved substrates were found to be different from those of normal cells: a) the nuclei of neoplastic cells, in contrast to those of the normal ones, did not undergo additional elongation on the cylindrical areas of the substrate; b) the orientation of neoplastic cells with regard to the axis of the cylindrical substrate was decreased or absent; c) the migration of neoplastic cells from certain types of the grooves was decreased. It is suggested that the different reaction to the geometry of the substrate may be a characteristic feature of transformed cells. Possible mechanisms of these alterations are discussed.