Diagnosis of Helicobacter pylori

The different invasive and noninvasive diagnostic tests for Helicobacter pylori have been applied mainly in emerging countries. Molecular methods have been developed, especially a test for detection of H. pylori and its clarithromycin resistance directly from stools. The long-term effects of eradication on histologic lesions have been studied in a meta-analysis and the prognostic value of post-treatment in gastric mucosa-associated lymphoid tissue lymphoma has been assessed. An operating link for gastritis assessment (the OLGA staging) has also been published. Attempts to simplify the urea breath test protocol have been made, and new stool antigen tests have been proposed and compared to those previously available.     

Features of moss mat structure and productivity in forest-bog complexes of West Siberia

The species composition and distribution of mosses over microrelief features on bogs have been assessed with various types of the water-mineral nutrient supply. The density of moss stalks in different moss species mats has been examined. Fraction analysis has been applied to weight and morphological characteristics of moss stalks. The contributions made by each fraction to the biomass production have been estimated. The linear and weight parameters of the photosynthesizing layer in mosses have been determined.     

Spatial distribution of oil in groundnut and sunflower seeds by nuclear magnetic resonance imaging

Abstract. The nuclear magnetic resonance imaging technique has been used to obtain images of different transverse and vertical sections in groundnut and sunflower seeds. Separate images have been obtained for oil and water components in the seeds. The spatial distribution of oil and water inside the seed has been obtained from the detailed analysis of the images. In the immature groundnut seeds obtained commercially, complementary oil and water distributions have been observed. Attempts have been made to explain these results.     

Measurement and study of the nose and face and their correlations in the young adult of Han nationality

The measurement of 13 items in the face and nose of 220 young adults (110 males and 110 females) of the Han nationality between the ages of 18 and 21 years has been done in the Henan Province of China. The means and standard deviations have been obtained, and the significant differences in many items between males and females have been proved. Some items influencing outer nasal shape have been analyzed. The correlations between nose height, nose length, and morphologic facial height and physiognomic facial height have been discussed. The ratio and amount of nasal breadth to facial breadth and nasal breadth to interocular breadth have been compared and analyzed, and the differences among the different races and between the sexes have been explained.     

Cloning, mapping and gene product identification of rhaT from Escherichia coli K12

Rhamnose utilization requires the function of a specific rhamnose transport system. Rhamnose transport mutants have been isolated and characterized. The structural gene, rhaT, encoding the rhamnose permease has been cloned from Escherichia coli. rhaT has been mapped in the rha locus (87.7 min) by analysis of cotransduction with glpK and other rha markers. The precise location of the gene has been determined by complementation analysis of rhamnose transport mutants transformed with recombinant plasmids containing different fragments of the cloned region. Gene order (counterclockwise) is established as glpK . . . rhaT-rhaR-rhaS-rhaB-rhaA-rhaD. The gene product has been identified by expression of rhaT in a T7 RNA polymerase/promoter system. This 23 kDa protein has been assigned to the rhaT product and has been shown to be located in the cell membrane.     

The effect of ultrasound on the antigenic activity of human erythrocytes

The effect of ultrasound (frequency 0.88 MHz, intensity from 0.05 to 1 W/cm2) on alterations in antigenic activity has been investigated in vitro using ABO antigens of human erythrocytes. The existence of threshold doses of ultrasound influence has been found. These doses are shown to be independent of ultrasound intensity. The dependence of the effect on erythrocyte concentration has been established. Individual and group differences in the antigenic resistance to ultrasonic exposure in donors of groups A and B have been revealed. A drop in antigenic activity equal to 97% has been obtained.     

Ethological approach in the study of aggressive behavior in monkeys

The aggressive behavior of 7 species of monkeys has been investigated. The definition of aggressive behavior has been suggested. The elements have been classified into three groups: warning, conflicting, contacting. The qualitative and quantitative characteristics of behavior permitting to determine the level of its development in representatives of different species have been proposed. The general principles of development of aggression such as the prevalence of the warning elements and its frequency, the curtailment of aggressive behavior etc. have been revealed. The differences in the aggressive behavioral characteristics are found to be specific and may be used in primate Taxonomy.     

Mechanisms and control of rapid genomic changes in flax

BACKGROUND AND AIMS: The nuclear DNA of certain varieties of flax (Linum usitatissimum) can vary within a single generation when the plants are grown under specific environmental conditions. This review details the genomic variations that have been identified and associated with this environmental response. CONCLUSIONS: The variation occurs across the whole spectrum of sequence repetition and has been shown to occur in the highly repeated, middle repetitive and low copy number sequences. Although the variation has been shown to be spread throughout the genome it does not occur at random, as similar molecular events have been shown to occur repeatedly. The changes in two labile regions in the nucleus, the ribosomal RNA genes and a site-specific insertion event, have been shown to occur within the period of vegetative growth and over a relatively short period of that growth. The gradual change in total nuclear DNA that has been described would then need to have arisen through an accumulation of changes occurring over the whole, or most of the, period of growth prior to flowering. The polymorphisms that result from these rapidly occurring genomic events have also been observed in many other flax and linseed varieties as well as in the wild progenitors of flax.     

Experimentally verified model of mechanomyograms recorded during single motor unit contractions

The aim of the paper is to create a model which enables to observe the mechanomyographic (MMG) wave generated during single motor unit contractions in a muscle, while the muscle is immersed in paraffin oil. The muscle model is described as a rheological membrane. Both the muscle and the medium models have been built by using Stiff-Finite-Element-Method (SFEM), which allows one to simulate the muscle surface displacement and the acoustic propagation of this effect in the oil. Such a modelling enables one to determine the impact of the rheological properties of the liquid environment on the shape of the MMG wave. In order to verify the model, the MMG signals and the contraction forces have been recorded in vivo from the medial gastrocnemius muscle of a rat. In these experiments single motor units were stimulated with various stimulation frequencies. A piezotransducer, immersed in paraffin oil, has been used to record the MMG signal recording. The signals recorded during individual twitches of the motor units have been used to estimate the parameters of the model. Subsequently, the model has been experimentally verified. The signals recorded in experiments during unfused and fused tetani have been compared with the simulated model responses in the analogous stimulation program. It has been observed that the MMG signals obtained with the proposed linear model have been consistent with the results of in vivo experiments.     

Use of Ranks in Comparisons of Variability in the Non-Normal Populations

A method of analysis for comparing the variability of two samples drawn from two populations has been developed. The method is also suitable for the nonnumeric form of data. A test based on ordered observations for testing the null hypothesis of equality of two variances has been given. The test statistic is a function of the sum of ranks assigned to smaller size sample. Ranking procedure has been modified to depict the variability in the data by the sum of ranks. The null distribution of the test-statistic has been worked out for small samples and it turns out to be chi-square distribution for large samples. The analytical procedure has been explained by a numerical example on the productivity and production of rice and wheat in India from 1950–51 to 1983–84.     

Persistence of bacterial pathogens as a physiological phenomenon

The complex ecosystem of humans and microbes has been presented as an associative symbiosis based on a mutual support of symbionts with different consequences for them. Conditions for the persistence of bacteria have been defined: their resistance to environmental factors, antagonism in biocenosis, and stability to withstand host defense mechanisms. The key role of bacterial peptidoglycan has been defined for their survival in an infected organism, and the classification for persistent mechanisms of pathogens has been given. The group of bacterial secreted protease providing microbial resistance to defense factors of the organism has been described. Host colonizing resistance has been presented as a physiological regulatory system controlling bacterial penetration into an organism. Regulatory mechanisms for bacterial persistence have been discussed.     

Salivary peroxidases

Summary Peroxidases are known to be involved in the intracellular metabolism of H₂O₂ coupled with various physiological functions. Apart from the thyroid gland, the enzyme has been isolated from various extrathyroidal sources of which salivary gland is one of the richest sources of the enzyme. The enzyme from bovine and goat submaxillary gland has been extensively studied in terms of their molecular, spectral, kinetic, catalytic and immunological properties and compared with the lactoperoxidase which is similar to the salivary peroxidase. The modulation of the salivary peroxidase by various factors and the probable mechanism of the modulation has been described. The enzyme has also been compared with the thyroid peroxidase as regards their physicochemical properties as well as on the immunological and functional aspects. The similarities and dissimilarities have been incorporated. The possible function of the enzyme in iodine metabolism and in bactericidal action has been discussed.[/p]     

Characteristics of Symmetric Surface Plasmon Polariton Mode in Glass–Metal–Glass Waveguide

The propagation characteristics of symmetric surface plasmon polariton mode in a glass–metal–glass waveguide are presented. Gallium lanthanum sulfide has been taken as the glass and silver (Ag) has been used as the metal. The analysis has been done both numerically and analytically. A two-dimensional finite-difference time-domain-based simulation model has been developed in order to analyze the propagation characteristics numerically. The obtained results using numerical and analytical methods have been compared and a very good agreement has been found.     

Anti-ischemic protection of the brain using water-soluble form of aspirin-acelisin]

The domestic water-soluble aspirin (acelisin) has been used as an anti-ischemic brain protector. The total brain ischemia has been implemented in accordance with an original technique for 17 to 35 min. The doses of acelisin from 25 to 250 mg/kg have been tested during experiments. The infusion of solutions has been carried out before ischemia, 15 min before reperfusion and just after the beginning of reperfusion. The functional status and survival of rats have been evaluated during a week. The best result has been reached with 150 mg/kg acelisin injected 30 min before ischaemia. A positive effect was reported when acelisin was used in early postischaemic period.     

On-line monitoring and control of substrate concentrations in biological processes by flow injection analysis systems

Concentrations of substrates, glucose, and ammionia in biological processes have been on-line monitored by using glucose-flow injection (FIA) and ammonia-FIA systems. Based on the on-line monitored data the concentrations of substrates have been controlled by an on-off controller, a PID controller, and a neural network (NN) based controller. A simulation program has been developed to test the control quality of each controller and to estimate the control parameters. The on-off controller often produced high oscillations at the set point due to its low robustness. The control quality of a PID controller could have been improved by a high analysis frequency and by a short residence time of sample in a FIA system. A NN-based controller with 3 layers has been developed, and a 3(input)-2(hidden)-1(output) network structure has been found to be optimal for the NN-based controller. The performance of the three controllers has been tested in a simulated process as well as in a cultivation process ofSaccharomyces cerevisiae, and the performance has also been compared to simulation results. The NN-based controller with the 3-2-1 network structure was robust and stable against some disturbances, such as a sudden injection of distilled water into a biological process.     

Sedimentation equilibrium of proteins in density gradients.

The technique of sedimentation equilibrium in density gradients in the analytical ultracentrifuge has been applied to the study of proteins. A variety of effects and procedures including the use of density marker beads, the effects of pressure on buoyant density and pH, and the calculation of compositional density gradient proportionality constants and density--refractive index relations have been developed. The buoyant densities of twenty-four proteins have been measured and hydration values computed. The buoyant titrations of six proteins have been measured. These data have been interpreted in terms of the buoyant titrations which have been obtained for six ionizable homopolypeptides, five copolypeptides, two non-ionizable homopolypeptides and three chemically modified proteins. Spectropolarimetry and potentiometric titrations were employed to further interpret these data. Approximate values for dissociation constants, numbers of ionizable residues, and the nature of ions bound or dissociated upon ionization have been obtained. The relation between potentiometric and buoyant titrations and the use of density gradient centrifugation as a probe for protein structure have been explored.     

Epidemiological assessment of the microbial contamination of the breast milk of healthy women

The qualitative and quantitative composition of the microflora of human milk has been studied. The dynamics of the occurrence of different microorganisms constituting the microflora at different periods of lactation has been established. The connection between the appearance of septic purulent infections in infants and the microbial contamination of milk has been revealed. The presence of Staphylococcus aureus in human milk in an amount of 500 microbial cells/ml has been found to constitute no menace to healthy infants.     

INHIBITION OF PROTEIN SYNTHESES DURING MEIOSIS AND ITS BEARING ON INTRACELLULAR REGULATION

Several parameters of meiosis have been studied in cultured anthers of Trillium erectum. The accessibility of labeled substrates to meiotic cells and the fate of these substrates in relation to meiotic stage have been determined. Evidence has been adduced for the synthesis of RNA and protein during the meiotic cycle well after chromosome duplication. The effect of interfering with systems directly or indirectly connected with protein formation has been studied by means of chloramphenicol, 8-azaguanine, 5-methyltryptophan, and ethionine. Administration of these reagents at different intervals in the cycle elicits correspondingly different responses thereby indicating a periodicity in the activities of different systems. The following processes have been shown to be affected in these experiments: chromosome segregation, chromosome morphology, cytokinesis, wall synthesis, and enzyme appearance. The possibility of experimentally altering the normal sequence of events has also been shown.     

Emerging antibiotic resistance in bacteria with special reference to India

The antibiotic era started in the 1940s and changed the profile of infectious diseases and human demography. The burgeoning classes and numbers promised much and elimination of this major cause of human (and animal) morbidity appeared possible. Bacterial antibiotic resistance which was observed soon after antibiotic introduction has been studied extensively. Diverse mechanisms have been demonstrated and the genetic basis elucidated. The resilience of the prokaryote ecosystems to antibiotic stress has been realized. The paper presents these subjects briefly to afford an overview. The epidemiology of antibiotic resistance is dealt with and community practices in different countries are described. The role of high antibiotic usage environments is indicated. The implication of the wide use of antibiotics in animals has been pointed out. Steadily increasing antibiotic resistance and decreasing numbers of newer antibiotics appear to point to a post-antibiotic period during which treatment of infections would become increasingly difficult. This article attempts to review the global antimicrobial resistance scene and juxtaposes it to the Indian experience. The prevalence in India of antibiotic resistance among major groups of pathogens is described. The factors that determine the prevalent high antibiotic resistance rates have been highlighted. The future research activity to ensure continued utility of antibiotics in the control of infections has been indicated.