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Vascular endothelial growth factor receptor 2 (VEGF-R2) is a marker of angiogenesis and metastasis of cancer. Two biosensors for the determination of VEGF-R2 in plasma have been developed. One of them is based on a pure gold chip, and the other on a silver/gold bimetallic chip; both have the receptor, monoclonal rabbit antibody specific for human VEGF-R2, attached to the chip via a cysteamine linker. The biosensor with the gold chip exhibits linearity of the analytical signal between 0.03 and 2 ng/mL, a precision of 1.4% and recovery between 99% and 102%. The biosensor with the bimetallic chip exhibits linearity between 0.03 and 1 ng/mL, a precision of 2.2% and recovery between 99% and 103%. Both biosensors tolerate a 1:100 excess of VEGF, VEGF-R1 and VEGF-R3. Both biosensors were validated by parallel determination of VEGF-R2 in 27 different plasma samples using the ELISA immunosensor assay, with very good agreement of the results. Thermodynamic parameters of the interaction of VEGF-R2 with the antibody were determined by QCM (Quartz Crystal Microbalance) and SPRi (Surface Plasmon Resonance imaging) measurements.

The purpose of this article is to present the use of Juri Lotman’s semiotic tools to reflect on the process of translating scientific texts. The article focuses on a text of a special type – an ethnographic material by Eugeniusz Frankowski (1884–1962), a Polish ethnologist of the interwar period. The outbreak of World War I found him in Spain – during his time, he wrote several texts in Spanish, Portuguese and Basque, including the work La lucha entre el hombre y los espíritus malos por la posesión de la tierra y su usufructo (translated by the author into Polish as “Zmagania człowieka ze złymi duchami o posiadanie ziemi i jej użytkowanie”). Research fluctuations (both terminological and methodological) are evident in the very “texture” of the text, so translating La lucha… into Polish required sensitivity to the mechanisms occurring at the confluence of biographical and textual levels. Using semiotic tools, the author reveals a series of research, textual, and methodological uncertainties for the researcher, resulting from the need to use different scientific languages (Polish, Spanish, French, German, etc.) to describe the newly explored terrain. This is because the awareness of the existence of these uncertainties sensitizes the very work of the translator, who is both an archaeologist, fleshing out successive levels of meaning, and a creator, co-thinking with Lotman’s notion of text as a “generator of meanings”.

A new method was developed for the simultaneous determination of vascular endothelial growth factor (VEGF-A) and fibroblast growth factor-2 (FGF-2) in blood serum, using biosensors with array Surface Plasmon Resonance imaging (SPRi) detection. It can be applied as a single method for simultaneous VEGF-A and FGF-2 determination or as two separate methods for testing only one selected protein in each case. Validation was carried out for each method. Limit of detection (LOD) and limit of quantification (LOQ) values were determined and were found not to differ significantly from the parameters obtained in comparisons with commercial enzyme-linked immunosorbent assay (ELISA) tests. Tests were carried out to check the robustness of the method. The results indicate a lack of robustness of the analytical method to elevated temperature and pH values other than those recommended by the manufacturers of the reagents (recommended pH = 7.40). The values of recoveries were determined and confirmed the reliability of the results obtained with the use of the newly developed method. The selectivity studies showed no negative influence of other proteins present in the matrix of the tested samples on the results of the VEGF-A and FGF-2 concentration measurements. The developed method is also characterized by high reproducibility of the results obtained and agreement with the VEGF-A and FGF-2 concentration values obtained with commercial ELISA tests. The proposed method offers fast, reproducible, and accurate simultaneous quantification of VEGF-A and FGF-2 in human body fluids. Only 4 µL of test sample are required for simultaneous analysis. The total time for simultaneous analysis of both biomarkers does not exceed 20 min. The developed analytical method is superior to ELISA in terms of analysis time and sample volume for analysis, and it offers lower LOD and LOQ values and allows for the simultaneous analysis of two biomarkers. There is also no need to collect a large number of samples. Standard ELISAs usually have 96 reaction wells. The proposed biosensor can be used to analyse only one sample, without the need to waste reagents on unused reaction sites. In addition, it is possible to regenerate the biosensor and reuse it.

Abstract Background The experience with running various types of classification on the CAMDA neuroblastoma dataset have led us to the conclusion that the results are not always obvious and may differ depending on type of analysis and selection of genes used for classification. This paper aims in pointing out several factors that may influence the downstream machine learning analysis. In particular those factors are: type of the primary analysis, type of the classifier and increased correlation between the genes sharing a protein domain. They influence the analysis directly, but also interplay between them may be important. We have compiled the gene-domain database and used it for analysis to see the differences between the genes that share a domain versus the rest of the genes in the datasets. Results The major findings are: pairs of genes that share a domain have an increased Spearman’s correlation coefficients of counts;genes sharing a domain are expected to have a lower predictive power due to increased correlation. For most of the cases it can be seen with the higher number of misclassified samples;classifiers performance may vary depending on a method, still in most cases using genes sharing a domain in the training set results in a higher misclassification rate;increased correlation in genes sharing a domain results most often in worse performance of the classifiers regardless of the primary analysis tools used, even if the primary analysis alignment yield varies. Conclusions The effect of sharing a domain is likely more a results of real biological co-expression than just sequence similarity and artifacts of mapping and counting. Still, this is more difficult to conclude and needs further research. The effect is interesting itself, but we also point out some practical aspects in which it may influence the RNA sequencing analysis and RNA biomarker use. In particular it means that a gene signature biomarker set build out of RNA-sequencing results should be depleted for genes sharing common domains. It may cause to perform better when applying classification. Reviewers This article was reviewed by Dimitar Vassiliev and Susmita Datta.

Introduction. The correlation between psoriasis and metabolic syndrome has been well established. Psoriasis may also coexist with autoimmune blistering disease, mainly bullous pemphigoid. The pathogenetic relationship between psoriasis and pemphigoid remains unclear. It is highly likely that IL-17 might be a common factor underlying the coexistence of pemphigoid with psoriasis and metabolic syndrome. Objective . Presentation of a patient with coexisting psoriasis vulgaris, bullous pemphigoid and metabolic syndrome. Case report . We present a 35-year-old man with enormous obesity and suffering from psoriasis from the age of 20 who developed tense blisters with annular arrangement localized mainly on the trunk, the proximal part of extremities and oral mucous membrane. On the basis of direct immunofluorescence study of skin biopsy and BIOCHIP study the diagnosis of pemphigoid was established. Moreover, the patient’s physical examination and the detailed analysis of laboratory tests led to the diagnosis of metabolic syndrome. Conclusions . To our knowledge, it is the first report demonstrating the development of psoriasis and pemphigoid in a patient with metabolic syndrome. Although the nature of this unique coincidence is not clear at the moment, methotrexate seems to be the first-line regimen for such cases.

Im jungen demokratischen Polen finden in der letzten Zeit heftige Diskussionen über die demokratischen Bildung und deren Methoden: gleichzeitig wird die Kondition polnischen Schulsystems ins Visier genommen. Vor allem wirft man der polnischen Schule, about it dass sie ihre Absolventen ohne grundlegende kognitive und praktische Kompetenzen frei lässt: besonders knapp sind da selbständiges Denken und Problemlösenfähigkeit.