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151.
Daniel Octavian Costache Oana Feroiu Adelina Ghilencea Mihaela Georgescu Ana Cruntu Constantin Cruntu Sorin George
iplica Mariana Jinga Raluca Simona Costache 《International journal of molecular sciences》2022,23(9)
The systemic inflammatory syndrome concept is one of the foundations that stand at the basis of revolutionary modern and future therapies, based on the in-depth understanding of the delicate mechanisms that govern the collaboration between the systems and organs of the human body and, at the same time, the fine balance that ensures a reproach-free operation. An interesting concept that we propose is that of the environment-inadequacy status, a concept that non-specifically incorporates all the situations of the organism’s response disorders in the face of imprecisely defined situations of the environment. The correlation between these two concepts will define the future of modern medicine, along with the gene-adjustment mechanisms. Psoriasis is a clear example of an inadequate body response as a result of exposure to as of yet undefined triggers with an excessive systemic inflammatory reaction and hitherto insufficiently controllable. Modern biological therapies, such as TNF-α, IL-12 family, and IL-17 inhibitors, are intended to profoundly reshape the cytokine configuration of patients with inflammatory diseases such as psoriasis, with tremendous success in disease control. Yet, because of the important roles of cytokines in cancer promotion and control, concern was raised about the fact that the use of biologicals may alter immune surveillance and promote cancer progression. Both theoretical and practical data nevertheless showed that the treatment-induced control of cytokines may be beneficial for reducing the inflammatory milieu that promotes cancer and such have a beneficial role in maintaining health. We briefly present the intricate roles of those cytokine families on cancer control, with some debates on if their inhibition might or might not promote additional tumoral development. 相似文献
152.
Eva Tvrd Daniel Lovíek Elika Glov Marianna Schwarzov Eva Kov
ikov Simona Kunov Jana
iarovsk Miroslava Ka
niov 《International journal of molecular sciences》2022,23(15)
This study focused on the identification of bacterial profiles of semen in normozoospermic men and their possible involvement in changes to the sperm structural integrity and functional activity. Furthermore, we studied possible fluctuations of selected cytokines, oxidative markers, and antibacterial proteins as a result of bacterial presence in the ejaculate. Sperm motility was assessed with computer-assisted sperm analysis, while sperm apoptosis, necrosis and acrosome integrity were examined with fluorescent methods. Reactive oxygen species (ROS) generation was quantified via luminometry, sperm DNA fragmentation was evaluated using the TUNEL protocol and chromatin-dispersion test, while the JC-1 assay was applied to evaluate the mitochondrial membrane potential. Cytokine levels were quantified with the biochip assay, whilst selected antibacterial proteins were quantified using the ELISA method. The predominant species identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were Staphylococcus hominis, Staphylococcus capitis and Micrococcus luteus. The results revealed that the sperm quality decreased proportionally to the increasing bacterial load and occurrence of conditionally pathogenic bacteria, including Enterococcus faecalis, Staphylococcus aureus and Escherichia coli. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains to ampicillin, vancomycin, tobramycin, and tetracycline. Furthermore, an increased bacterial quantity in semen was accompanied by elevated levels of pro-inflammatory cytokines, including interleukin-1, interleukin-2, interleukin-6, tumor necrosis factor alpha as well as ROS overproduction and lipid peroxidation of the sperm membranes. Our results suggest that semen quality may be notably affected by the bacterial quantity as well as quality. It seems that bacteriospermia may be associated with inflammatory processes, oxidative stress, sperm structural deterioration, and a subsequent risk for the development of subfertility, even in normozoospermic males. 相似文献
153.
Andreea Campu Ilinca Muresan Ana-Maria Craciun Simona Cainap Simion Astilean Monica Focsan 《International journal of molecular sciences》2022,23(14)
Acute myocardial infarction (AMI) is considered as one of the main causes of death, threating human lives for decades. Currently, its diagnosis relies on electrocardiography (ECG), which has been proven to be insufficient. In this context, the efficient detection of cardiac biomarkers was proposed to overcome the limitations of ECG. In particular, the measurement of troponins, specifically cardiac troponin I (cTnI) and cardiac troponin T (cTnT), has proven to be superior in terms of sensitivity and specificity in the diagnosis of myocardial damage. As one of the most life-threatening conditions, specific and sensitive investigation methods that are fast, universally available, and cost-efficient to allow for early initiation of evidence-based, living-saving treatment are desired. In this review, we aim to present and discuss the major breakthroughs made in the development of cTnI and cTnT specific biosensor designs and analytical tools, highlighting the achieved progress as well as the remaining challenges to reach the technological goal of simple, specific, cheap, and portable testing chips for the rapid and efficient on-site detection of cardiac cTnI/cTnT biomarkers in order to diagnose and treat cardiovascular diseases at an incipient stage. 相似文献
154.
Constantin Filote Raluca-Andreea Felseghi Maria Simona Raboaca Ioan Aşchilean 《国际能源研究杂志》2020,44(13):10471-10494
The Electric Vehicle (EV) as a clean alternative to Classic Vehicle that use fossil fuels is promoted as an immediate solution to improve the quality parameters of the environment related to the transport sector. The transition to clean electrified mobility must be considered from the sustainability spectrum, and the planning of a strategy related to the implementation of electric vehicles implies, from the beginning, providing clean energy conditions to go toward a green-to-green paradigm. It should be noted that the successful implementation of the “green electro mobility” concept depends heavily on the green energy supply solutions of green electric vehicle, so Electric Vehicle Charging Stations (EV-CS) should be powered by electricity generation systems based on green resources. This research article has as main objective the environmental impact assessment from the perspective of CO2 emissions embedded in green stand-alone energy systems and the estimation of the environmental benefits of their implementation in the power supply of EV-CS from the perspective of avoided CO2 emissions compared to the classic electricity supply grid. The results indicate that the green energy systems represent feasible solutions for the independent energy support of electric vehicle charging stations, being able to supply electricity based on on-site available 100% alternative energy sources. Related to 1 kWh of electricity, the CO2 emissions embedded in these systems represent on average 11.40% of the CO2 emissions of the electricity supplied through the grid at European level and on average 7.10% of the CO2 emissions of the electricity supplied through the grid worldwide. Results also show that the average price of 1kWh of electricity generated by the analyzed systems is 4.3 times higher than the average unit price of the European Union grid energy, but this indicator must be correlated with the kgCO2/kWh cost savings compared to the electricity production from classic power plants. 相似文献
155.
156.
Mindaugas Bulota Simona Sriubaite Anne Michud Kaarlo Nieminen Mark Hughes Herbert Sixta Michael Hummel 《应用聚合物科学杂志》2021,138(17):50306
Fiber-reinforced composites based on natural fibers are promising alternatives for materials made of metal or synthetic polymers. However, the inherent inhomogeneity of natural fibers limits the quality of the respective composites. Man-made cellulose fibers (MMCFs) prepared from cellulose solutions via wet or dry-jet wet spinning processes can overcome these limitations. Herein, MMCFs are used to prepare single fiber epoxy composites and UD composites with 20, 30, 40, and 60 wt% fiber loads. The mechanical properties increase gradually with fiber loading. Young's modulus is improved three times while tensile strength doubles at a loading of 60 wt%. Raman spectroscopy is employed to follow conformational changes of the cellulose chains within the fibers upon mechanical deformation of the composites. The shift of the characteristic Raman band under strain indicates the deformation mechanisms in the fiber. Provided stress transfer occurs through the interface, it is a direct measure of the fiber-matrix interaction, which is investigated herein. The shift rate of the 1095 cm−1 band decreases in single fiber composites compared to the neat fibers and continues to decrease as the fiber loading increased. 相似文献
157.
158.
159.
Petr Kluson Libor Cerveny Marie Krivska Jiri Had Simona Laurentova 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,59(4):409-415
Charcoal-, silica-, alumina- and titanium(IV) oxide-supported ruthenium catalysts, prepared by conventional impregnation and incipient wetness methods from a ruthenium(III) oxide precursor were tested in copper(II) formate decomposition in aqueous solution. Such a reaction was found to be an efficient and simple activity test of charcoal-supported catalysts. The application of this reaction for a bimetallic ruthenium–copper catalyst preparation was also suggested. Experimental results were compared with those obtained using commercial catalysts and ruthenium black. 相似文献
160.
Sofia Guzzetti Simona Perotto Alessandro Veneziani 《International journal for numerical methods in engineering》2018,114(5):469-500
Hierarchical model reduction is intended to solve efficiently partial differential equations in domains with a geometrically dominant direction. In many engineering applications, these problems are often reduced to 1‐dimensional differential systems. This guarantees computational efficiency yet dumps local accuracy as nonaxial dynamics are dropped. Hierarchical model reduction recovers the secondary components of the dynamics of interest with a combination of different discretization techniques, following up a natural separation of variables. The dominant direction is generally solved by the finite element method or isogeometric analysis to guarantee flexibility, while the transverse components are solved by spectral methods, to guarantee a small number of degrees of freedom. By judiciously selecting the number of transverse modes, the method has been proven to improve significantly the accuracy of purely 1‐dimensional solvers, with great computational efficiency. A Cartesian framework has been used so far both in slab domains and cylindrical pipes (including arteries) mapped to Cartesian reference domains. In this paper, we investigate the alternative use of a polar coordinates system for the transverse dynamics in circular or elliptical pipes. This seems a natural choice for applications like computational hemodynamics. In spite of this, the selection of a basis function set for the transverse dynamics is troublesome. As pointed out in the literature—even for simple elliptical problems—there is no “best” basis available. In this paper, we perform an extensive investigation of hierarchical model reduction in polar coordinates to discuss different possible choices for the transverse basis, pointing out pros and cons of the polar coordinate system. 相似文献