Chemiluminescent multiassay of pesticides with horseradish peroxidase as a label

Competitive chemiluminescent immunoassay based on a combination of five antibodies was used in a combination with neural network to identify and estimate amounts of three cross-reacting s-triazines (atrazine, terbythylazine and ametryn). Antibodies with different cross-reactivity towards s-triazines were immobilized in separate wells an eight-well microtiter strip. Training of neural networks was carried out with four different learning procedures. The best topology for the data measured was a net with two hidden layers with ten neurons in the first and 15 in the second layer trained with the Schmidhuber method. s-Triazine classification of environmental samples containing various analyte mixtures was correct in 70-100% of all cases depending on the type of analyte. The test developed can be proposed as an alternative field test for multianalyte environmental monitoring.     

Production of recombinant hIL-4delta2-a native isoform of human interleukin-4 in Escherichia coli cells

Expression plasmids containing the synthetic gene hil-4 delta 2 was constructed to produce human interleukin-4 in Escherichia coli cells. Strains TG1 (pBTIL-4 delta 2) and BL21 (DE3) (pETIL-4 delta 2) produced the recombinant protein as inclusion bodies, and its production level was up to 30% of the total cell protein. The renatured hIL-4 delta 2 inhibited IL-4-stimulated T cell proliferation, and this effect was enhanced by cyclosporin A.     

Aspartate- and alanine-aminotransferase in early development of keta

We studied the activities of the marker enzymes of physiological state and adaptive reactions, aspartate and alanine aminotransferases, in early development of the keta Oncorhynchus keta. Aspartate aminotransferase with pH optima 6.8, 7.0, 7.6, and 8.0 and alanine aminotransferase with pH optima 7.0, 7.4, 7.6, 7.8, 8.0, and 8.2 were found in the eggs, larvae, and fry. The succession of enzymes with different pH takes place during ontogenesis, as well as stage specific changes in their activity. The maximum enzymatic activity was recorded in the larvae during their rise for "afloat." A correlation was established between the dynamics of enzymatic activity and soluble nitrogen and amine nitrogen contents.     

Diagnostic value of different laboratory methods in the diagnosis of pneumonia caused by Haemophilus influenzae type B

Comparative analysis of the diagnostic value of different laboratory methods in the diagnosis of H. influenzae b (Hib) pneumonia in children (bacteriological method, latex agglutination, counter immunoelectrophoresis, the passive hemagglutination test and the enzyme immunoassay (EIA) was carried out. EIA proved to be the most informative method for the diagnosing Hib pneumonia. EIA makes it possible to detect specific Hib antigens in different clinical materials in 48.8% of cases, as well as high titers of antibodies to mis infective agent in 61.7% of cases. The authors propose the unified criteria of the laboratory diagnosis of Hib infection in children.     

Support vector regression applied to the determination of the developmental age of a Drosophila embryo from its segmentation gene expression patterns

MOTIVATION: In this paper we address the problem of the determination of developmental age of an embryo from its segmentation gene expression patterns in Drosophila. RESULTS: By applying support vector regression we have developed a fast method for automated staging of an embryo on the basis of its gene expression pattern. Support vector regression is a statistical method for creating regression functions of arbitrary type from a set of training data. The training set is composed of embryos for which the precise developmental age was determined by measuring the degree of membrane invagination. Testing the quality of regression on the training set showed good prediction accuracy. The optimal regression function was then used for the prediction of the gene expression based age of embryos in which the precise age has not been measured by membrane morphology. Moreover, we show that the same accuracy of prediction can be achieved when the dimensionality of the feature vector was reduced by applying factor analysis. The data reduction allowed us to avoid over-fitting and to increase the efficiency of the algorithm.     

Aminotransferases in early development of salmonid fish

The activities of alanine and aspartate aminotransferases were assessed in the embryos and juveniles of the rainbow trout Parasalmo mykiss L. and chum salmon Oncorhynchus keta W. Changes in subcellular localization of these enzymes and their activities were found at different pH optima in each subcellular fraction of the rainbow trout during ontogenesis.__________Translated from Ontogenez, Vol. 36, No. 2, 2005, pp. 96–101.Original Russian Text Copyright © 2005 by Samsonova, Lapteva, Filippovich.     

Non-linear regression models for time to flowering in wild chickpea combine genetic and climatic factors

Background

Accurate prediction of crop flowering time is required for reaching maximal farm efficiency. Several models developed to accomplish this goal are based on deep knowledge of plant phenology, requiring large investment for every individual crop or new variety. Mathematical modeling can be used to make better use of more shallow data and to extract information from it with higher efficiency. Cultivars of chickpea, Cicer arietanum, are currently being improved by introgressing wild C. reticulatum biodiversity with very different flowering time requirements. More understanding is required for how flowering time will depend on environmental conditions in these cultivars developed by introgression of wild alleles.

Results

We built a novel model for flowering time of wild chickpeas collected at 21 different sites in Turkey and grown in 4 distinct environmental conditions over several different years and seasons. We propose a general approach, in which the analytic forms of dependence of flowering time on climatic parameters, their regression coefficients, and a set of predictors are inferred automatically by stochastic minimization of the deviation of the model output from data. By using a combination of Grammatical Evolution and Differential Evolution Entirely Parallel method, we have identified a model that reflects the influence of effects of day length, temperature, humidity and precipitation and has a coefficient of determination of R²=0.97.

Conclusions

We used our model to test two important hypotheses. We propose that chickpea phenology may be strongly predicted by accession geographic origin, as well as local environmental conditions at the site of growth. Indeed, the site of origin-by-growth environment interaction accounts for about 14.7% of variation in time period from sowing to flowering. Secondly, as the adaptation to specific environments is blueprinted in genomes, the effects of genes on flowering time may be conditioned on environmental factors. Genotype-by-environment interaction accounts for about 17.2% of overall variation in flowering time. We also identified several genomic markers associated with different reactions to climatic factor changes. Our methodology is general and can be further applied to extend existing crop models, especially when phenological information is limited.

     

Glutamine synthetase content and immunochemical analysis of different strains of Bordetella pertussis

In this investigation 3 groups of strains isolated from pertussis patients have been studied: typical (group 1), atypical in their cultural properties (group 2), unidentified Gram-negative bacilli agglutinated by pertussis and parapertussis antitoxins (group 3). Besides, B. pertussis cultures, obtained by subculturing 2 museum strains and 2 newly isolated strains on synthetic casein-charcoal agar with subinhibiting doses of antibiotics or specific immune sera added, have been studied. As indicated by the results of this study, strains belonging to groups 1 and 2 contain glutamine synthetase, while in strains of group 3 this enzyme is absent. In immunoelectrophoresis strains of group 3 have been found to contain not a single antigen similar to the antigens of strains belonging to groups 1 and 2. Electrophoresis in polyacrylamide gel has revealed to differences in the protein spectrum of the strains of these 3 groups. The investigation has shown that the determination of glutamine synthetase and immunoelectrophoresis can be used for the differentiation of B. pertussis from similar Gram-negative bacilli. B. pertussis strains, changed as the result of experiments with antibiotics and specific immune sera, have also been shown to retain their antigenic composition and protein spectrum and to have no essential difference in the content of glutamine synthetase.