Volume 14, number 3
Editorial
Worldwide Scientist
New Books
Bioprocess systems
Bioprocess Engineering and the Manners-Gandolfi X-ray Camera171-178
A Shannon, Chin Khen Wong
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The purpose of this paper is to outline the mathematical design in the Manners X-ray camera in which a hypocycloidal gear system was used in order to avoid coincidences of planes in a certain type of X-ray crystallography
Discrimination between contaminating and commensal strains of Staphylococcus epidermidis (Search for phenotypic virulence criteria in Staphylococcus epidermidis)179-186
Aija Žileviča, TatjanaTracevska, Iveta Liduma, Uldis Viesturs
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Staphylococcus epidermidis strains are diverse in their pathogenicity. Some are invasive virulent strains causing serious nosocomial infections; some are skin commensals with a low virulence. The discrimination of them is of great clinical significance. To analyze the implication of different factors in virulence, phenotypical methods were applied. Comparative assessment of the enzymatic activity of nosocomial and commensal strains of S. epidermidis was performed: alkaline phosphatase (PHA), beta-glucosidase (LAC ), arginine dehydrolase (ARG), urease (URE), maltosidase (PAM), N-acetylglutamic acid hydrolase (FPY), N-acetylglucosaminehydrolase (FGA ) were studied. Differences were found in the urease activity, i.e. 93% and 77% of commensal and nosocomial strains, respectively, were positive.
In sheep blood agar, the difference was more significant - only 16.7% of commensal strains demonstrated the haemolytic activity, but 52.4% of nosocomial strains occurred to be haemolytic.
Investigation of the Properties of Covalent Immobilized Anti-aflatoxin B1 Antibody on Membranes from Copolymer of Polyacrylamide-polyacrylonitrile187-196
Lyubov Yotova, Nedka Trifonova, Terry Vrabcheva, Vasilka Mironova, Vasilena Chuchuranova
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Aflatoxins are toxic secondary metabolites produced by a number of different fungi (Aspergillus flavus, Aspergillus parasiticus), and can be present in a wide range of food and feed commodities. The most used methods for analysis of aflatoxins are thin-layer chromatography, high-performance liquid chromatography (HPLC), electrochemical immunoanalysis and microtitre plate enzyme-linked immunosorbent assay (ELISA). Membranes from copolymer of polyacrylamide-polyacrylonitrile have been prepared. These membranes were used as a matrix for a covalent binding of polyclonal anti-aflatoxin B1 antibody. ELISA was carried out with these membranes to prove successful immobilization of the antibody. It was done comparative analysis with ELISA between standard microtiter plate and our membranes with infected peanuts.
Enzymatic Hydrolysis of Various Proteins of Wheat in Heterogeneous Conditions197-202
Hasan Hasanov, Muyassar Zakirova, Akmal Boboev, Nodira Akbarova
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Enzymatic hydrolysis of different proteins isolated from wheat flour by neutral proteinase (neutraza "Novozymes") was studied. It was shown, that hydrolysis of alkaline proteins was 10-11 times higher as compared with albumin from wheat, 3-4 times higher than alcohol soluble proteins and 2-2.5 times higher than globulins. It was found that, hydrothermal treatment of wheat flour decreased the rate of protein hydrolysis. The rate of hydrolysis of native alkaline soluble proteins was 4-6 times higher than denaturized proteins. The rate of hydrolysis of denatured water-soluble proteins is 3-5 times higher as compared with native protein (albumin). It was shown that product of thermal degradation of raw materials also influence on the rate of protein hydrolysis.
Biomedical systems
An Automated Algorithm for Fast Pulse Wave Detection203-216
Bistra Nenova, Ivo Iliev
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This study presents an automated algorithm for fast pulse wave detection, directed to establishing the presence of cardiac activity in an emergency. The method relies on real-time estimation of similarity of closely positioned rising edges of the waveform and decision logic. The algorithm was tested on a set of pressure pulse waves from the MGH/MF waveform database from PhysioNet. Our approach to assessing the algorithm performance was based on location and classification of suspicious 10 s signal epochs by means of detection of dissimilar peak-to-peak intervals. The detected epochs were visually inspected and compared to the corresponding ECG-based expert beat annotations. The main epoch and error types were summarized. The performance of the algorithm and the visual interpretation of the results were illustrated by means of examples. The review of the recordings showed that the proposed algorithm correctly identifies cardiac pulsations even under considerable artefacts. Our conclusion is that the algorithm reliably detects critical periods in cardiac activity and is applicable to fast pulse wave detection in real-time applications and ambulatory measurement setups.

© 2010, BAS, Institute of Biophysics and Biomedical Engineering