Direct T-2 Toxicity on Human Skin—Fibroblast Hs68 Cell Line—In Vitro Study

T-2 toxin is produced by different Fusarium species, and it can infect crops such as wheat, barley, and corn. It is known that the T-2 toxin induces various forms of toxicity such as hepatotoxicity, nephrotoxicity, immunotoxicity, and neurotoxicity. In addition, T-2 toxin possesses a strong dermal irritation effect and can be absorbed even through intact skin. As a dermal irritant agent, it is estimated to be 400 times more toxic than sulfur mustard. Toxic effects can include redness, blistering, and necrosis, but the molecular mechanism of these effects still remains unknown. This in vitro study focused on the direct toxicity of T-2 toxin on human skin—fibroblast Hs68 cell line. As a result, the level of toxicity of T-2 toxin and its cytotoxic mechanism of action was determined. In cytotoxicity assays, the dose and time-dependent cytotoxic effect of T-2 on a cell line was observed. Bioluminometry results showed that relative levels of ATP in treated cells were decreased. Further analysis of the toxin’s impact on the induction of apoptosis and necrosis processes showed the significant predominance of PI-stained cells, lack of caspase 3/7 activity, and increased concentration of released Human Cytokeratin 18 in treated cells, which indicates the necrosis process. In conclusion, the results of an in vitro human skin fibroblast model revealed for the first time that the T-2 toxin induces necrosis as a toxicity effect. These results provide new insight into the toxic T-2 mechanism on the skin.     

Synthesis of 1-propenyl ethers and their using as modifiers of UV-cured coatings in radical and cationic polymerization

The 1-propenyl ethers of diols and polyols have recently attracted increasing attention as monomers and comonomers because these compounds undergo UV-photoinitiated polymerization. The synthesis of 1-propenyl ethers via the isomerization of corresponding, readily available allyl ethers catalysed by homogenized transition metal complexes with recycling of catalyst has been described. The properties of UV-cured coatings have been investigated for various compositions containing: the model ether (i.e. 1,4-di(1-propenyloxy)-butane), the unsaturated polyester resin [Estromal 103] or epoxy resin [Epidian 6] and radical (i.e. Irgacure 184) or cationic (i.e. triarylsulfonium salts with metal halide anions: PF₆⁻, SbF₆⁻) initiators. The purified or unrefined (i.e. including 0.05 mol% homogenized ruthenium(II) complex [RuClH(CO)(PPh₃)₃]) 1,4-di(1-propenyloxy)butane were applied as modifiers. The effect of presence of homogenized [RuClH(CO)(PPh₃)₃] in the composition has been discussed.     

Evaluation of virtual environment as a form of interactive resuscitation exam

There is scientific evidence confirming the effectiveness of e-learning within resuscitation, however, there is not enough research on modern examination techniques within the scope. The aim of the pilot research is to compare the exam results in the field of Advanced Life Support in a traditional (paper) and interactive (computer) form as well as to evaluate satisfaction of the participants. A survey was conducted which meant to evaluate satisfaction of exam participants. Statistical analysis of the collected data was conducted at a significance level of α?=?0.05 using STATISTICS v. 12. Final results of the traditional exam (67.5%?±?15.8%) differed significantly (p?<?0.001) from the results of the interactive exam (53.3%?±?13.7%). However, comparing the number of students who did not pass the exam (passing point at 51%), no significant differences (p?=?0.13) were observed between the two types exams. The feedback accuracy as well as the presence of well-prepared interactive questions could influence the evaluation of satisfaction of taking part in the electronic test. Significant differences between the results of a traditional test and the one supported by Computer Based Learning system showed the possibility of achieving a more detailed competence verification in the field of resuscitation thanks to interactive solutions.     

Nutritional status of Cuban elders in three different geriatric scenarios: community, geriatrics service, nursery home

The undernutrition rates observed in Cuban elders surveyed in three different geriatric scenarios: Community: coastal town of Cojímar (City of Havana); Geriatrics Service ("Hermanos Ameijeiras" Hospital, City of Havana); and Nursery Home (city of Cárdenas, province of Matanzas) by means of the Mini Nutritional Assessment (MNA) of the Elderly are presented. Undernutrition rates were 2.7% among elders surveyed in the coastal community of Cojímar, but increased to become 91.6% among those admitted to the hospital Geriatrics Service, and 95.3% for those institutionalized in the Nursery Home, respectively. The occurrence of undernutrition can be low among elders living freely in the community, but it might affect a vast number of those seeking medical assistance at the public health institutions. Extent of undernutrition among elders in geriatric assistance scenarios should lead to the adoption of the required measures for early identification, and timely treatment, of this health problem.     

An attempt to improve the evaluation of mechanical material properties from the Axisymmetric Tensile Test

This paper deals with new analytical modeling of the classical tensile test with an axisymmetric sample and determining the yield stress of elasto-plastic materials under the neck formation. Known for many years, classical Bridgman and Siebel-Davidenkov-Spiridonova's formulas provide certain errors, especially visible in the case of weakly hardening or ideal-plastic materials. Accurate numerical simulations of the process allowed verification of the analytical results. Based on the numerical simulations, some modifications of the analytical models and their derivation have been proposed which enabled the elimination of the two most questionable classic assumptions. Comparison of new results with well-known formulas shows that some progress is reached for small plastic deformations; however, for greater strain level further improvement is still advisable.     

Multiphysics simulation of laser–material interaction during laser powder depositon

This work reports a theoretical and numerical study of the parameters related to the process of laser powder deposition through a lateral nozzle. For this purpose, a 3D quasi-stationary finite element model was developed analytically and implemented numerically. The proposed model estimates the shape of the melt pool depending on the process parameters including scanning speed, powder mass flow, laser power, and physical properties. Also, phase transformations and physical properties (density, thermal conductivity, and specific heat) vary as function of temperature. In addition, thermo-capillary forces and their effect on fluid flow inside the melt pool are considered. The obtained set of equations coupled through the temperature variable was solved using COMSOL Multiphysics. The results are presented and compared with previously obtained experimental data, in which chromium powder was deposited, allowing validation of the model. Finally, variations at the melt pool geometry in terms of the operational parameters are analyzed. This model aims at estimation of melt pool geometry during laser powder deposition in time reasonably short to allow for predictable process control.     

A descriptive study to provide evidence of the teratogenic and cellular effects of sibutramine and ephedrine on cardiac‐ and liver‐tissue of chick embryos

Exposure to drugs during pregnancy is a major concern, as some teratogenic compounds can influence normal foetal development. Although the use of drugs during pregnancy should generally be avoided, exposure of the developing foetus to teratogens may occur unknowingly since these compounds may be hidden in products that are being marketed as “all natural.” The aim of the current study was to investigate the possible teratogenic and cellular effects of sibutramine—a serotonin‐norepinephrine reuptake inhibitor used in the treatment of obesity—on the heart and liver tissue of chick embryos. Ephedrine was used as a positive control. The chick embryo model was chosen because it has been used in studying developmental and experimental biology and teratology with great success. The embryos were exposed to three different concentrations of sibutramine and ephedrine respectively. The results obtained revealed that both compounds exhibited embryotoxicity when compared to the control groups. Liver and heart tissue of the exposed embryos was severely affected by these compounds in a dose‐related manner. Morphology similar to that of muscle dystrophy was observed in the heart, where the muscle tissue was infiltrated by adipose and connective tissue. Severe liver steatosis was also noted. A more in‐depth investigation into the molecular pathways involved might provide more information on the exact mechanism of toxicity of these products influencing embryonic development. Microsc. Res. Tech. 78:737–746, 2015. © 2015 Wiley Periodicals, Inc.     

Diurnal Profiles of Melatonin Synthesis-Related Indoles,Catecholamines and Their Metabolites in the Duck Pineal Organ

This study characterizes the diurnal profiles of ten melatonin synthesis-related indoles, the quantitative relations between these compounds, and daily variations in the contents of catecholamines and their metabolites in the domestic duck pineal organ. Fourteen-week-old birds, which were reared under a 12L:12D cycle, were killed at two-hour intervals. The indole contents were measured using HPLC with fluorescence detection, whereas the levels of catecholamines and their metabolites were measured using HPLC with electrochemical detection. All indole contents, except for tryptophan, showed significant diurnal variations. The 5-hydroxytryptophan level was approximately two-fold higher during the scotophase than during the photophase. The serotonin content increased during the first half of the photophase, remained elevated for approximately 10 h and then rapidly decreased in the middle of the scotophase. N-acetylserotonin showed the most prominent changes, with a more than 15-fold increase at night. The melatonin cycle demonstrated only an approximately 5-fold difference between the peak and nadir. The 5-methoxytryptamine content was markedly elevated during the scotophase. The 5-hydroxyindole acetic acid, 5-hydroxytryptophol, 5-methoxyindole acetic acid and 5-methoxytryptophol profiles were analogous to the serotonin rhythm. The norepinephrine and dopamine contents showed no significant changes. The DOPA, DOPAC and homovanillic acid levels were higher during the scotophase than during the photophase. Vanillylmandelic acid showed the opposite rhythm, with an elevated level during the daytime.     

Effects of rainbow trout freshness on n‐3 polyunsaturated fatty acids in fish offal

The effects of rainbow trout cold storage on the quality of offal left after fish processing to fillets with skin were determined. The intact farmed rainbow trout were kept at 2 °C in ice for 0, 4, 7, and 14 days of storage. The offal was, immediately after processing, frozen at ?20 °C and analysed after a month‐long frozen storage; fillets (non‐frozen) were analysed as well. Non‐protein nitrogen, volatile bases, trimethylamine, lipid oxidation (peroxide value, anisidine value, UV‐VIS spectra, and fluorescence) and fatty acid composition were determined. The offal consists in 15% of protein and in about 20% of chloroform/methanol‐extractable lipids, with n‐3 polyunsaturated fatty acids (n‐3 PUFA) accounting for 20.37 ± 1.25% of the fatty acids. The fish storage duration was found to exert a significant (p = 0.05) effect on the changes in lipids and nitrogen compounds. No losses of long‐chain n‐3 PUFA in the offal were detected during the 2 wk of storage in ice plus 1 month at ?20 °C. The rainbow trout offal is a valuable – rich and stable – source of n‐3 PUFA.     

Onium Salts of Amino Acids as Co‐Initiators in Photoinduced Free‐Radical Polymerization

Summary: The onium salts of selected aliphatic and aromatic amino acids were investigated as electron donors in photoinduced free radical polymerization, in conjunction with either DIBF or BP as sensitizer. The laser flash photolysis experiments unmistakably documented that the free radical formation occurs via an electron transfer reaction from the amino acid salt to the chromophore triplet state. The kinetic studies clearly showed that either the DIBF or BP onium salts of selected aliphatic and aromatic sulfur‐containing amino acids exhibit a significant increase in the efficiency of free‐radical polymerization of TMPTA as compared to non‐sulfur‐containing co‐initiators and that the efficiency of all tested electron donors is only slightly dependent on the cation type coupled with co‐initiators tested.

Possible mechanism for the free radical photoinitiated polymerization.