ChannelsDB: database of biomacromolecular tunnels and pores

ChannelsDB (http://ncbr.muni.cz/ChannelsDB) is a database providing information about the positions, geometry and physicochemical properties of channels (pores and tunnels) found within biomacromolecular structures deposited in the Protein Data Bank. Channels were deposited from two sources; from literature using manual deposition and from a software tool automatically detecting tunnels leading to the enzymatic active sites and selected cofactors, and transmembrane pores. The database stores information about geometrical features (e.g. length and radius profile along a channel) and physicochemical properties involving polarity, hydrophobicity, hydropathy, charge and mutability. The stored data are interlinked with available UniProt annotation data mapping known mutation effects to channel-lining residues. All structures with channels are displayed in a clear interactive manner, further facilitating data manipulation and interpretation. As such, ChannelsDB provides an invaluable resource for research related to deciphering the biological function of biomacromolecular channels

Study of the effect of paracetamol binded in polymeric nanoparticles on dafnia magna.

Drugs are important xenobiotics in the environment. Their use increases with the growth of the human population, but also in agricultural primary production. Paracetamol (PAR) is a widely used analgesic and antipyretic and its production is still growing. Commonly available drug production technologies are being developed very intensively with nanotechnological modifications for their gradual and targeted release. Nanoparticles (ST/PAR) from starch were prepared: PAR (0, 1, 2, 3, 5 and 10 mg/L) was mixed with citric acid ester in a 1:8 v/v ratio for 30 min at 25 °C. By the centrifugation (16.000 g, 30 min) ST/PAR were obtained in the pellet. The effect of PAR was studied on Daphnia magna Straus (Cladocera, Crustacea). Adult females (70-400 mg) were used for self-evaluation. The EC50 was 3.749 mg/L after 48 h of PAR treatment. Total protein values determined by Lowry method were between 0.5-2.2 mg/mL and by Bradford method between 190-676 mg/L. Antioxidant activity values determined by CUPRAC method were between 4-15 μg/mL GAE and by ABTS method ranged between 40-103 μg/mL GAE. PAR values were between 9-40 μM. Subsequently, the biological activity of the prepared nanoparticles was tested

Phytotoxicity of silver nanoparticles (AgNPs) prepared by green synthesis using sage leaves (Salvia officinalis).

Silver nanoparticles (AgNPs) are widely investigated with regard to their physical, chemical, but also biological properties. Antibacterial and antitumor properties of AgNPs have been intensively studied. In addition, the synthesis using a green approach brings further significant biological properties. However, it is also necessary to monitor the potential toxicity of such nanoparticles in different ecosystems. In this study, the effect of AgNO3 and AgNPs on germinated plants of Zea mays was studied. Effects on basic growth and physiological parameters were observed. There was a statistically significant difference between the variants tested

3D-printed CdTe QDs-based sensor for sensitive electrochemical detection of viral particles.

Preventing the spread of dangerous viral diseases such as flu, Ebola or HIV requires rapid and effective diagnostic approaches to detect these diseases at an early stage. Quantum dots (QDs) are nanocrystals that exhibit a variety of unique properties and are suitable for biomolecule labelling due to their high stability, ease of preparation, and biocompatibility. Modified QDs can be used to label nucleic acids or antibodies. Green synthesis method of QDs provides a platform for preparation of unique materials with new chemical or physical properties as compared to the original material. In this work, CdTe QDs were produced in the presence of plant extract which acted as a modifying agent. The Zea mays extract was added during the CdTe QDs synthesis at different time intervals and CdTe QDs showed a wide range of colors. The stability of the prepared QDs, including their application onto paper, was evaluated. The QDs were observed to show a remarkable electrochemical response for sensor applications and were also employed to label virus-specific antibody. The entire procedure was miniaturized and the viral particles were analyzed in a 3D-printed chip

Biophysical analysis of silver nanoparticles prepared by green synthesis and their use for 3D printing of antibacterial material for health care.

The resistance of microorganisms to antibiotics is growing steadily. The development of new antibacterial agents is highly topical. Metal nanoparticles have shown significant antibacterial activity similar to the plant/animal materials used in traditional medicine. The study focuses on the synthesis of silver nanoparticles (AgNPs) modified with biomolecules from used plant extracts (T. serpyllum, S. officinalis, T. pratense). The obtained nanoparticles were studied in detail by physicochemical methods. In addition, they were deposited on acrylonitrile butadiene styrene (ABS). We created unique antibacterial material using 3D printing. 20-40% inhibition of S. aureus and E. coli was observed in the evaluation of their efficacy

An assessment of the effect of green synthesized silver nanoparticles using sage leaves (Salvia officinalis L.) on germinated plants of maize (Zea mays L.).

AgNPs have attracted considerable attention in many applications including industrial use, and their antibacterial properties have been widely investigated. Due to the green synthesis process employed, the nanoparticle surface can be coated with molecules with biologically important characteristics. It has been reported that increased use of nanoparticles elevates the risk of their release into the environment. However, little is known about the behaviour of AgNPs in the eco-environment. In this study, the effect of green synthesized AgNPs on germinated plants of maize was examined. The effects on germination, basic growth and physiological parameters of the plants were monitored. Moreover, the effect of AgNPs was compared with that of Ag(I) ions in the form of AgNO3 solution. It was found that the growth inhibition of the above-ground parts of plants was about 40%, and AgNPs exhibited a significant effect on photosynthetic pigments. Significant differences in the following parameters were observed: weights of the caryopses and fresh weight (FW) of primary roots after 96 h of exposure to Ag(I) ions and AgNPs compared to the control and between Ag compounds. In addition, the coefficient of velocity of germination (CVG) between the control and the AgNPs varied and that between the Ag(I) ions and AgNPs was also different. Phytotoxicity was proved in the following sequence: control < AgNPs < Ag(I) ions

The Eighth Central European Conference "Chemistry towards Biology": snapshot

The Eighth Central European Conference "Chemistry towards Biology" was held in Brno, Czech Republic, on 28 August – 1 September 2016The Eighth Central European Conference "Chemistry towards Biology" was held in Brno, Czech Republic, on 28 August-1 September 2016 to bring together experts in biology, chemistry and design of bioactive compounds; promote the exchange of scientific results, methods and ideas; and encourage cooperation between researchers from all over the world. The topics of the conference covered "Chemistry towards Biology", meaning that the event welcomed chemists working on biology-related problems, biologists using chemical methods, and students and other researchers of the respective areas that fall within the common scope of chemistry and biology. The authors of this manuscript are plenary speakers and other participants of the symposium and members of their research teams. The following summary highlights the major points/topics of the meeting

Rozbor problematiky vestavěných řídících systémů s obvody FPGA

Import 19/06/2007Prezenční455 - Katedra měřicí a řídicí technik

Multiplexer for automatic testing of multimedia units

This article deals with automatic testing of multimedia units. The aim of the work was to design and implement an automatic test system for a functional parameter measurement of multimedia units. The system was built up with the help of individual measuring devices and the designed multiplexer. The multiplexer functions are described in detail. The entire system is controlled by the control computer. For the control computer it was necessary to create software to control with devices and multimedia unit and communicate with them. For creating utility programs, the Labview programming language and Teststand software tool from National Instruments were chosen

Green synthesized quantum dots as electrochemical labels for sensitive detection of hemorrhagic fever virus.

Virus-induced haemorrhagic fevers often show a rapid, dramatic course. Infectivity and mortality are very high. Such viruses are known to attack primates as well as other animal species. Fast, sensitive, selective diagnostics can be very beneficial for early anti-epidemic measures right in the outbreak. Quantum dots (QDs) have excellent features that make them useful as detection labels. Their use increases the sensitivity of the analytical assay. The use of biologically active components in QDs synthesis brings new properties. Quantum dots are nanocrystals that due to their high stability, ease of preparation and biocompatibility are suitable for labeling biomolecules. CdTe QDs modified with mercaptosuccinic acid (MSA), reduced glutathione (GSH), and plant extracts were prepared. Green synthesized CdTe QDs showed emission depending on the amount of extract applied. Thus, QDs were prepared in full-color scale from blue to red. The modified biomolecules of QDs are applicable for the labeling of nucleic acids. Their long-term stability, including their application onto paper, was tested. CdTe QDs exhibit very good electrochemical detection with the limit of detection (LOD) in nanomolar concentration