Optimization of Novel Human Acellular Dermal Dressing Sterilization for Routine Use in Clinical Practice

Gamma rays and electrons with kinetic energy up to 10 MeV are routinely used to sterilize biomaterials. To date, the effects of irradiation upon human acellular dermal matrices (hADMs) remain to be fully elucidated. The optimal irradiation dosage remains a critical parameter affecting the final product structure and, by extension, its therapeutic potential. ADM slides were prepared by various digestion methods. The influence of various doses of radiation sterilization using a high-energy electron beam on the structure of collagen, the formation of free radicals and immune responses to non-irradiated (native) and irradiated hADM was investigated. The study of the structure changes was carried out using the following methods: immunohistology, immunoblotting, and electron paramagnetic resonance (EPR) spectroscopy. It was shown that radiation sterilization did not change the architecture and three-dimensional structure of hADM; however, it significantly influenced the degradation of collagen fibers and induced the production of free radicals in a dose-dependent manner. More importantly, the observed effects did not disrupt the therapeutic potential of the new transplants. Therefore, radiation sterilization at a dose of 35kGy can ensure high sterility of the dressing while maintaining its therapeutic potential.     

Effects of Various Energy Suppliers in Green Processes for Obtaining Silver Nanoparticles

The productions of stable suspensions of silver nanoparticles using a microwave reactor, an ultraviolet (UV) reactor, a low‐frequency low‐temperature plasma reactor, a high‐pressure reactor, and an open reactor are compared. All reactors served as sources of energy for stimulating the nanoparticle growth process. The silver nanoparticles were obtained based on the chemical reduction method. The processes were conducted using gallic acid as the reducing‐stabilizing substance. The influence of the variable parameters time (for all types of reactors), temperature (for the open and high‐pressure reactors), power (for the microwave reactor), energy density (for the UV reactor), and voltage (for the low‐frequency low‐temperature plasma reactor) was investigated. Temperature was found to be the most important factor influencing all processes.     

Comparison of antimicrobial resistance of Campylobacter jejuni and Campylobacter coli isolated from humans and chicken carcasses in Poland

Campylobacter-associated gastroenteritis remains an important cause of morbidity worldwide, and some evidence suggests that poultry is an important source of this foodborne infection in humans. This study was conducted to analyze the prevalence and genetic background of resistance of 149 Campylobacter jejuni and 54 Campylobacter coli strains isolated from broiler chicken carcasses and from stool samples of infected children in Poland from 2003 through 2005. Nearly all isolates were susceptible to macrolides and aminoglycosides. The highest resistance in both human and chicken strains was observed for ciprofloxacin (more than 40%), followed by ampicillin (13 to 21%), and tetracycline (8 to 29%). Resistance to ampicillin and tetracycline rose significantly between 2003 and 2005. Slight differences in resistance between human and chicken isolates indicate that although chicken meat is not the only source of Campylobacter infection in our population, it can be involved in the transmission of drug-resistant Campylobacter strains to humans.     

Monitoring of transient temperature and thermal stresses in pressure components of steam boilers

Two methods of solving the transient inverse heat conduction problens in complex shaped elements are presented in this paper. The time-space temperature distribution in whole element cross-section is reconstructed using the measured temperature histories at several points placed inside the element or on its easily accessible outer surface. Thermal stresses are then evaluated involving Finite Element Analysis. In both methods the heat transfer coefficient at the element inner surface is the unknown value. Four examples are presented, two for one method showing the high accuracy of the presented methods and possibility of their practical application.     

The Use of a Novel Ferulic Acid Esterase from Lactobacillus acidophilus K1 for the Release of Phenolic Acids from Brewer's Spent Grain

In this work, an extracellular ferulic acid esterase was produced in bioreactor cultivations of Lactobacillus acidophilus K1 strain. The enzyme was partially purified using ultrafiltration (10 kDa), dialysis (4–6 kDa) and Fast Protein Liquid Chromatography (Sepharose CM, Sephacryl S‐300). A considerable increment of enzyme activity (31‐fold) in the final preparation was achieved. Two distinct bands (approx. 21.5 kDa and 39 kDa) were obtained after SDS‐PAGE. A high similarity of the purified enzyme (LC‐MS/MS analysis) to tannase and ferulic acid esterase from Burkholderia ambifaria MEX‐5 was obtained. The optimal pH and temperature for the enzyme activity were 6.3 and 37°C, respectively. The enzyme preparation effectively released phenolic acids (mainly ferulic and p‐coumaric acid) from brewer's spent grain. This novel enzyme preparation can be used for the utilisation of a valuable and inexpensive by‐product of the brewing industry.     

A comparison of selected quality features of the tissue and slaughter yield of wild and cultivated pikeperch<Emphasis Type="Italic"> Sander lucioperca</Emphasis> (L.)

The study focused on the comparison of carcass and fillet yields, fillet color, the content of basic components, and the fatty acid composition of tissue from cultivated and wild pikeperch. There was no variation in yield between carcasses and fillets. The brightness and redness of the color of the fillet surfaces of both types of fish were comparable, although the yellowness, chromaticity and shade of color differed. The tissue of cultivated fish had three times more fat (2.87%) than did that of wild fish; the difference was compensated for by water content. The protein and mineral component contents did not vary significantly. The total levels of saturated and monounsaturated acids in the tissue lipids in 1 g of fat varied. No differences were observed between the total amount of polyunsaturated fatty acids (PUFA), PUFAn-3, PUFAn-6, or in the n-3/n-6 proportion. One consequence of the higher fat content in cultivated pikeperch tissue was that the contents of eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic (DHA; 22:6n-3) acids per 100 g of fillet were significantly higher than in the tissue of wild pikeperch.     

New covalent salts of the 4+ V class for Li batteries

There is urgent action required for replacing LiPF₆ as a solute for Li-ion batteries electrolytes. This salt, prone to highly Lewis acidic PF₅ release and hydrolysis to HF is responsible for deleterious reaction on carbonate solvents, corrosion of electrode materials leading to safety problems then release to toxic chemicals. A major advantage of LiPF₆ is that it passivates aluminium. Most attempts to replace LiPF₆ with hydrolytically-stable salts have been unsuccessful because of Al corrosion.We present here two “Hückel” type salts, namely lithium (2-fluoroalkyl-4,5-dicyano-imidazolate); fluoroalkyle = CF₃ (TDI), C₂F₅ (PDI) with high charge delocalization. These thermally stable salts give both appreciably conductive solutions in EC/DMC (>6 mS cm⁻¹ at 20 °C) with a lower decrease with temperature than LiPF₆. Non fluorinated lithium (4,5-dicyano-1,2,3-triazolate) is comparatively less than half as conductive. The lithium transference number T₊ measured by PFG-NMR is also higher. Voltammetry scans with either platinum or aluminium electrodes show an oxidation wall at 4.6 V versus Li⁺:Li°. These two salts are thus the first examples of strictly covalent, non-corroding salts allowing 4+ V electrode material operation. This is demonstrated with experimental Li/LiMn₂O₄ cells as beyond the third cycles, the fade of the three electrolytes were quasi-identical, though LiPF₆ had a sharper initial decrease.     

Effect of processing on the content of glucobrassicin and its degradation products in broccoli and cauliflower

The influence of thermal treatment, pickling and fermentation on the content of glucobrassicin and its selected breakdown products in broccoli and cauliflower was investigated. The highest content of glucobrassicin and the lowest content of its breakdown products were found in vegetables which underwent thermal treatment such as boiling and steam cooking. The lowest content of glucobrassicin and the highest content of its breakdown products were present in raw, pickled and fermented vegetables in which the myrosinase remained active. Ascrobigen was the major glucobrassicin breakdown product and its content was negatively correlated with glucobrassicin content in broccoli and cauliflower. After heating of vegetables in 60 °C for 20 min (causing thermal deactivation of epithiospecific protein) no presence of indole-3-acetonitrile was found.     

Application of computer vision systems for estimation of fat content in poultry meat

The paper presents the possibility of use a computer vision system (CVS) for estimation fat content in poultry meat. The estimation of this ingredient content was made in the material obtained in industrial conditions. Chicken and turkey carcasses were selected randomly, from which the thigh muscles (from chickens and turkeys) and chicken breast muscles were taken. Analysis of correlation was made between content of white spots achieved with CVS method and fat content determined using the reference Soxhlet method. According to the achieved results, it was concluded that the computer vision system for images of turkey thigh muscles can be used to estimate its fat content.