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Nanofiber dressing consisting of antisense rna-functionalized nanodiamonds for therapy of non-healing wounds in diabetic individuals
Neuhoferová, Eva ; Petráková, V. ; Vocetková, K. ; Kindermann, Marek ; Křivohlavá, Romana ; Benson, Veronika
Non-healing wounds are serious complication in diabetic patients and represent an attractive challenge for development of suitable carrier system possessing constant and localized release of therapeutic biomolecule into the wound without any undesired side effects. Given the fact that these non-healing wounds are result of impaired balance in metalloproteinases synthesized by immune cells residing the wounds, gene therapy offering knock down of such enzymes is of great interest. \nHere we challenged a development of functional and biocompatible wound dressing enabling controlled release of trackable carrier loaded with therapeutic siRNA. Our dressing consists of scaffold from degradable polymer nanofibers enriched with fluorescent nanodiamond particles (FND). We have previously shown the nanodiamond particles are great carriers for antisense RNAs. Their advantages represent high biocompatibility, stable luminescence giving us the possibility to track the carrier system in the wound, and effective release of antisense RNA in the wound. Embedding of nanodiamond-siRNA systems into nanofiber scaffold enables continuous release of siRNA and maintaining the stable siRNA concentration in the wound site resulting in a promotion of wound healing. \nWe developed FND-siRNA complexes specific to MMP-9 that efficiently inhibit the expression of target MMP-9 mRNA. The complexes were embedded into core/shell nanofibers from PVA and PCL, visualized by confocal microscopy, and characterized by electron microscopy. Real-time PCR was used to assess the silencing effect of siRNA that has been delivered to target murine fibroblasts by FND released from nanofiber dressing. Nanofiber system with embedded FNDs was applied on wounds in diabetic animal models to evaluate its suitability regarding short and long term toxicity, efficacy, and handling in vivo. \n
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Assessment of asp reproductive population in Švihov Reservoir in 2017
Šmejkal, Marek ; Blabolil, Petr ; Bartoň, Daniel ; Kolařík, T. ; Soukalová, Kateřina ; Děd, Vilém ; Boborová, K. ; Michalička, P. ; Zemanová, Z. ; Kočvara, Luboš ; Duras, J. ; Kubečka, Jan
The aim of the contract was to capture reproducing asp by electrofishing and tag fish individually using individual marking technique (PIT-tags). Estimate of asp reproductive population in the Švihov Reservoir was performed on the basis of mark-recapture methods. Furthermore, the length and weight increments were computed for recaptured asp individuals. Tagged individuals were monitored using passive telemetry systems on the tributary of Švihov Reservoir.
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Optimizing Flow and Segregaton Properties of Lactose/Microcrystalline Cellulose Mixture for Tablet Compression.
Zámostný, P. ; Kreibichová, B. ; Hofmanová, D. ; Kulaviak, Lukáš ; Zelenková, K. ; Růžička, Marek
The present study deals with optimizing the flow and segregation properties of levocetirizine hydrochloride formulation, where the delay between homogenization and tablet compression was found to affect the tablet content uniformity. In addition to API, the base formulation comprised spray dried lactose monohydrate, milled lactose monohydrate 200 mesh, Avicel PH 101 microcrystalline cellulose, and minor excipients. Several alternative mixtures were prepared using the same total composition, but different grades of lactose and microcrystalline cellulose. These mixtures were then tested for the segregation behavior in an in-house segregation device and the flow properties using the Freeman FT4 powder rheometer. The segregation tests showed the grade of lactose is essential for mixture in-flow segregation. While SD lactose mixtures increased the API content in a direction countercurrent to flow, the milled lactose mixtures segregated API concurrently. Mixtures using both lactose grades showed combined effect, resulting in the least segregation due to the two segregation processes competing with each other. However, the segregation was extremely sensitive to ageing of the mixture. It was also found that each type of lactose causes a different flow regime of the mixture in process vessels. In order to improve the content uniformity of the tablets, it was found the volumetric flow regime of transport to tablet press is required as well as the aggregate formation should be prevented.\n
Fulltext: content.csg -  PDF
Plný tet: PROCEEDINGS OF THE 3RD INTERNATIONAL CONFERENCE ON CHEMICAL TECHNOLOGY - PDF
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Corrosion behavior of plasma coatings CuAl10 and CuAl50 on magnesium alloy AZ 91
Kubatík, Tomáš František ; Stoulil, J. ; Stehlíková, K. ; Slepička, P. ; Janata, Marek
The most common magnesium alloy AZ 91 is widely used as a structural material, but its use is limited at higher temperatures and high humidity. Plasma spraying is a technology that allows to prepare protective metallic and non-metallic coatings on a wide variety of substrates including magnesium and its alloys. In this study, CuAl10 and CuAl50 were plasma sprayed on magnesium alloy AZ 91 with the aim to study corrosion resistance of the plasma sprayed coatings. The corrosion resistance of layers was evaluated by the method of electrochemical potentiodynamic measurement as well as long-term corrosion tests in a condensation chamber with 0.5 mol\nNaCl at the temperature of 35 °C for 1344 hours. Layers with 1, 2, 5 passes and passes of CuAl10 with the thickness ranging from 75 to 716 mm and CuAl50 with the thickness ranging from 64 to 566 mm were prepared. The increased corrosion velocity was observed in the case of thin layers of 2 and 5 passes due to the development of a galvanic corrosion couple. The CuAl10 layer prepared with ten passes has an outstanding corrosion resistance.
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Phosphorus recycling - need or urgency
Holba, Marek ; Došek, M. ; Škvoran, O. ; Matysíková, J. ; Plotěný, K. ; Maršálek, Blahoslav
Phosphate policy is tightly connected with effective solutions in agriculture, but also with its removal from water environment where excessive concentration of phosphorus is not welcomed since it causes water bloom and worsening og surface water quality. Phosphate ores will be depleted soon and therefore recacling technologies should be introduced into practice in near future. Struvite - slow-release fertilizer seems to be good commodity for farmers. Struvite is usually responsible for clogged pipes in the wastewater treatment area. Therefore, several technologies of its recycling is recently being developed, esp. from reject water stream. Struvite crystallization, its production control and scale-up of technology from lab-scale through pilot-sclae to full-scale is technological challenge in the near future.
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Markers of Oxidative Stress are Elevated in Workers Exposed to Nanoparticles
Pelclová, D. ; Ždímal, Vladimír ; Fenclová, Z. ; Vlčková, Š. ; Schwarz, Jaroslav ; Pušman, Jan ; Zíková, Naděžda ; Syslová, K. ; Kuzma, Marek ; Navrátil, Tomáš ; Zakharov, S. ; Kačer, P.
Health-effects of nanoparticles in humans are little understood. Pre-shift and post-shift spirometry, markers in exhaled breath condensate (EBC), and fractional exhaled nitric oxide (FeNO) were measured both in 20 workers exposed to TiO2 aerosol and 19 controls. Particle number size distributions were monitored by aerosol spectrometers SMPS and APS, covering the overall size range 15 nm-10 μm. Simultaneously, the spatial distributions of total particle number and mass concentrations were determined using a particle number concentration monitor (P-TRAK) and a monitor of particle mass concentrations (DustTRAK DRX). Total aerosol concentrations in the production plant varied greatly in both space and time; number concentrations 1x104-2x105 particles/cm3 and mass concentrations 0.1-30 mg/m3. In the workshops, 90% of the particles were smaller than 100 nm in diameter and particle concentrations were 10x higher than in the control room.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22013111914100 - PDF
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Influence of Physicochemical Factors on Gushing Mechanism
Poštulková, Michaela ; Novák, Pavel ; Vitoušová, K. ; Brányik, T. ; Růžička, Marek
Gushing is a negative phenomenon when a foam spontaneously gush out when a bottle or can is opened. Despite a long-term research the gushing still has not been fully explained. The problem of gushing is its seasonal variability, depending on the raw materials and processing technology. In addition, gushing intensity may change over the years. Furthermore, gushing also related to the fact that there is no simple and inexpensive method for measuring. The aim of this work was to find a suitable gushing matrix which could be helpful to study gushing in a new experimental pressure equipment. Simple and inexpensive apparatus was built for the study of overfoaming beer. The valve system (placed on the pressure equipment) control outlet/inlet gas and liquid phase. The pressure and temperature sensors can be also connected to the equipment. It is also possible to regulate the rate of decrease gas pressure above the liquid - the sudden reduction ideally simulates the classic opening beer bottles. A model solution of gushing liquid was created and the influence of the temperature, pressure and pH on the intensity of gushing was measured.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22013110513040 - PDF
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Reuse and energy potential of greywater
Bartoník, A. ; Holba, Marek ; Plotěný, K. ; Vrána, J. ; Ošlejšková, M.
Greywater is the leftover water from baths, showers, hand basins and washing machines only, what implies that it is free of faeces and urine. Greywater can be recycled on-site (called white water) for flushing toilets, urinals, landscape irrigation and constructed wetlands. The heat energy reuse from greywater has been recently discussed as a hot issue. Paper deals with the new British Standard BS 8525-1(2) that introduce the issue of greywater in buildings, as well as progress in the new Czech standard preparation. A various technologocial designs are introduced including return of investment analyses.
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