Successful Treatment of Persistent SARS-CoV-2 Infection in a B-Cell Depleted Patient with Activated Cytotoxic T and NK Cells: A Case Report

We report a lymphoma patient with profound B-cell deficiency after chemotherapy combined with anti-CD20 antibody successfully treated with remdesivir and convalescent plasma for prolonged SARS-CoV-2 infection. Viral clearance was likely attributed to the robust expansion and activation of TCR Vβ2 CD8+ cytotoxic T cells and CD16 + CD56- NK cells. This is the first presentation of TCR-specific T cell oligoclonal response in COVID-19. Our study suggests that B-cell depleted patients may effectively respond to anti-SARS-CoV-2 treatment when NK and antigen-specific Tc cell response is induced.     

Crack‐resistance behavior of polypropylene copolymers

Two heterophasic reactor‐grade propylene–ethylene copolymers (RAHECO®) were diluted with propylene–ethylene random copolymers to obtain materials with constant EPR/PE‐particle diameter but various interparticle distances. According to the results of instrumented impact tests, brittle‐to‐tough transitions were found at different temperatures. The critical interparticle distances shift linearly over the observed range of temperature. Critical interparticle distances could be determined not only in the region of predominantly unstable crack growth but also in the region of predominantly stable crack growth. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2317–2325, 2001     

The stability characterization of the pyrotechnic system. The degradation of the nitrate oxidant in the presence of the magnesium under the accelerated aging conditions

The degradation of the nitrate oxidant was followed in the course of the aging process of tracer pyrotechnic mix containing 22.0 % Mg, 46.0 % Sr(NO₃)₂, 22.0 % KCIO₄, 9.0 % Al-Mg alloy and 4.0 % organic binder. The accelerated aging was conducted under the conditions of the increased humidity (98.5 %, 85.0 %, 78.5 %) at the increased temperature (75 °C). Nitrate content as a function of aging time was calculated by substracting nitrite nitrogen from total nitrogen content determined by Devarda's alloy reduction method. The degradation products of the nitrate (nitrite and carbonate) were determined by UV/VlS (Griess reaction) and IR spectroscopy, respectively. Nitrate proved to have a great instability in the presence of the metal, the extent of its conversion to nitrite and carbonate being rather great in comparision to the previously studied alkali metal nitrates in the presence of Mg as well. The loss of the nitrate and the formation of the nitrite and carbonate are governed by the same kinetic laws as fuel degradation to the hydroxide. The rate of the metal oxidation to the hydroxide was faster than the rate of the nitrate degradation process. The failure of the mix is connected to the rather small content of the nitrite (0.4 %) while the texture was significantly destroyed.     

Modeling Lycopene Degradation and Isomerization in the Presence of Lipids

The kinetics of thermally induced degradation and isomerization of lycopene in olive oil, fish oil, and an olive oil/tomato emulsion were studied in detail. Special attention was paid to the isomerization reactions using a multi-response modeling approach. The type of oil had a significant impact on lycopene degradation kinetics, being faster in fish oil compared with olive oil. The estimated kinetic parameters to describe lycopene degradation in olive oil were not significantly different from those in an olive oil/tomato emulsion. The overall Z-isomer formation and elimination in olive oil, fish oil, and olive oil/tomato emulsion was similar. Only the kinetic parameters for 13-Z-lycopene formation differed significantly in the two oils. Although the isomerization rate constants for the emulsion were lower than for olive oil, the isomerization reactions showed similar temperature dependency. This study shows that the kinetics of thermally induced degradation and isomerization of lycopene in oil and in an olive oil/tomato emulsion can be described using the same model. The food system, however, has an influence on the model parameters, especially on the rate constants.     

Tire rubber–sisal composites: Effect of mercerization and acetylation on reinforcement

Tire rubber particles were mixed randomly with short sisal fibers and hot pressed. Sisal fibers were used as received, mercerized, and mercerized/acetylated. The fibers were characterized by scanning electron microscopy (SEM), thermal gravimetry analysis (TGA), infrared spectroscopy (FTIR), water sorption, and mechanical properties. Thermal stability of the mercerized/acetylated fibers improves (from 200 to 300°C) with respect to the raw fibers, and water sorption is ～ 20% smaller than for the raw and the mercerized fibers. Tensile strength is unchanged after the chemical treatments. Water sorption, mechanical properties, and SEM evaluated the performance of the tire rubber composites. All composites showed enhanced elastic modulus; increase is dependent on fiber load. Smallest water sorption was obtained in composites with the mercerized/acetylated fibers. With these fibers at 10% load, the best results were obtained with the smaller tire rubber particles (320 μm) and at 5% load with the bigger (740 μm) tire rubber particles. Both composites showed ～ 50% increase in tensile strength when compared to similar composites with raw fibers. SEM of the surface of fracture showed that the adhesion between fiber and rubber was enhanced after both chemical treatments. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2507–2515, 2003     

Anionic ring-opening polymerization of octamethylcyclotetrasiloxane in emulsion above critical micelle concentration

Batch anionic ring-opening polymerization of octamethylcyclotetrasiloxane in emulsion using nonionic and cationic emulsifiers was studied. The concentration of emulsifiers was set above their critical micelle concentration. Effects of emulsifier concentration, nonionic/cationic emulsifier ratio and cationic emulsifier/initiator (KOH) ratio on the kinetics, average particle size and distribution and on the average molecular weight and distribution were investigated and discussed. At the beginning of the polymerization, empty micelles, active micelles (polymer particles) and monomer droplets co-exist in emulsion. The transport of monomer from monomer droplets toward empty micelles was confirmed by monomer droplets and empty micelles disappearance and by formation of smaller particles. The transport of monomer from monomer droplets toward polymer particles was not confirmed, since the average polymer particle size did not increase during polymerization. It was proposed, that at lower conversions, monomer diffuses from polymer particle interior to particle surface, while at higher conversions, the monomer diffuses from larger to smaller polymer particles. Emulsifier concentration, nonionic/cationic emulsifier ratio and cationic emulsifier/KOH ratio have an evident effect on the kinetics and on the average molecular weight, thus demonstrating that cationic emulsifier participates to the initiation reaction.     

Neuroprotective Effects of VEGF in the Enteric Nervous System

Although the enteric nervous system (ENS) functions largely autonomously as part of the peripheral nervous system (PNS), it is connected to the central nervous system (CNS) via the gut–brain axis. In many neurodegenerative diseases, pathological changes occur in addition to gastrointestinal symptoms, such as alpha-synuclein aggregates in Parkinson’s disease, which are found early in the ENS. In both the CNS and PNS, vascular endothelial growth factor (VEGF) mediates neuroprotective and neuroregenerative effects. Since the ENS with its close connection to the microbiome and the immune system is discussed as the origin of neurodegenerative diseases, it is necessary to investigate the possibly positive effects of VEGF on enteric neurons. Using laser microdissection and subsequent quantitative RT-PCR as well as immunohistochemistry, for the first time we were able to detect and localize VEGF receptor expression in rat myenteric neurons of different ages. Furthermore, we demonstrate direct neuroprotective effects of VEGF in the ENS in cell cultures. Thus, our results suggest a promising approach regarding neuroprotection, as the use of VEGF (may) prevent neuronal damage in the ENS.     

Omega-3 Polyunsaturated Fatty Acids—Vascular and Cardiac Effects on the Cellular and Molecular Level (Narrative Review)

In the prevention and treatment of cardiovascular disease, in addition to the already proven effective treatment of dyslipidemia, hypertension and diabetes mellitus, omega-3 polyunsaturated fatty acids (n-3 PUFAs) are considered as substances with additive effects on cardiovascular health. N-3 PUFAs combine their indirect effects on metabolic, inflammatory and thrombogenic parameters with direct effects on the cellular level. Eicosapentaenoic acid (EPA) seems to be more efficient than docosahexaenoic acid (DHA) in the favorable mitigation of atherothrombosis due to its specific molecular properties. The inferred mechanism is a more favorable effect on the cell membrane. In addition, the anti-fibrotic effects of n-3 PUFA were described, with potential impacts on heart failure with a preserved ejection fraction. Furthermore, n-3 PUFA can modify ion channels, with a favorable impact on arrhythmias. However, despite recent evidence in the prevention of cardiovascular disease by a relatively high dose of icosapent ethyl (EPA derivative), there is still a paucity of data describing the exact mechanisms of n-3 PUFAs, including the role of their particular metabolites. The purpose of this review is to discuss the effects of n-3 PUFAs at several levels of the cardiovascular system, including controversies.