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1.
Patients with cancer are more susceptible to a higher risk of coronavirus infection and its severe complications than the general population. In addition, these patients were not included in the pivotal clinical trials for COVID-19 vaccines. Therefore, considerable uncertainty remains regarding the management of cancer patients during the COVID-19 pandemic and the safety of COVID-19 vaccinations in cancer patients. In this review, we summarize the current knowledge generated from the beginning of the COVID-19 pandemic on the vulnerability of cancer patients to the coronavirus disease, as well as the effectiveness of COVID-19 vaccines in this population. We also discuss the available data on the effects of anticancer treatment with immune checkpoint inhibitors on the immune responses to SARS-CoV-2 in cancer patients. Special attention in this review will be given to patients with lung cancer, as such patients are at an increased risk for severe effects from COVID-19.  相似文献   
2.
The extracellular matrix (ECM) is an important regulator of excitability and synaptic plasticity, especially in its highly condensed form, the perineuronal nets (PNN). In patients with drug-resistant mesial temporal lobe epilepsy (MTLE), hippocampal sclerosis type 1 (HS1) is the most common histopathological finding. This study aimed to evaluate the ECM profile of HS1 in surgically treated drug-resistant patients with MTLE in correlation to clinical findings. Hippocampal sections were immunohistochemically stained for aggrecan, neurocan, versican, chondroitin-sulfate (CS56), fibronectin, Wisteria floribunda agglutinin (WFA), a nuclear neuronal marker (NeuN), parvalbumin (PV), and glial-fibrillary-acidic-protein (GFAP). In HS1, besides the reduced number of neurons and astrogliosis, we found a significantly changed expression pattern of versican, neurocan, aggrecan, WFA-specific glycosylation, and a reduced number of PNNs. Patients with a lower number of epileptic episodes had a less intense diffuse WFA staining in Cornu Ammonis (CA) fields. Our findings suggest that PNN reduction, changed ECM protein, and glycosylation expression pattern in HS1 might be involved in the pathogenesis and persistence of drug-resistant MTLE by contributing to the increase of CA pyramidal neurons’ excitability. This research corroborates the validity of ECM molecules and their modulators as a potential target for the development of new therapeutic approaches to drug-resistant epilepsy.  相似文献   
3.
Therapy with mesenchymal stem cells (MSCs) is promising in many diseases. Evaluation of their efficacy depends on adequate follow-up of MSCs after transplantation. Several studies have shown that MSCs can be labeled and subsequently visualized with magnetic nanoparticles (NPs). We investigated the homing of MSCs labeled with magnetic cobalt ferrite NPs in experimentally induced acute kidney injury in mice. To explore the homing of MSCs after systemic infusion into mice, we developed a pre-infusion strategy for optimal tracing and identification of MSCs with polyacrylic acid-coated cobalt ferrite (CoFe2O4) NPs by light and transmission electron microscopy (TEM) in various organs of mice with cisplatin-induced acute kidney injury and control mice. By correlative microscopy, we detected MSCs labeled with NPs in the lungs, spleen, kidney, and intestine of cisplatin-treated mice and in the lungs and spleen of control mice. Our results confirm that labeling MSCs with metal NPs did not affect the ultrastructure of MSCs and their ability to settle in various organs. This study demonstrates the usefulness of cobalt ferrite NPs in ex vivo visualization of MSCs and offers correlative microscopy as a useful method in routine histopathology laboratories for tracing MSCs in paraffin-embedded tissue.  相似文献   
4.
This paper assesses groundwater recharge under conditions of long-term groundwater pumping at the Ravnik pumping site in Croatia and analyses the groundwater level prediction model used in prior aquifer modelling. The results of model calibration revealed a very low net infiltration rate at the start of the pumping site’s operation. As the operation continued, the net infiltration rate slowly increased, while the percentage of infiltrated rainfall scaled up with increasing pumping rates. The predicted recharge of the covering aquitard amounts approximately 14–15 % of the mean annual precipitation. The aquifer recharge takes place from aquitard by seepage. A subsequent simulation of the pumping site’s operation was performed for the 9 years period on the assumption that the pumping rates and the groundwater recharge would be the same as those recorded during the final calibration years. Results show that the post audit measured levels correspond relatively well to the predicted levels and that increasing of the pumping rate causes changes in the water budget in advantage of net groundwater recharge as a consequence of spreading recharge area outside of previous model boundaries.  相似文献   
5.
Es wurde der Einfluß wäßriger Gewürzextrakte und deren Mischungen auf die Aluminiumkorrosion in NaCl-Lösungen untersucht. Zur Bestimmung der Korrosionsströme und Korrosionspotentiale des Aluminiums wurden Modellösungen aus wäßrigen Gewürzextrakten (Pfeffer, Paprika, Knoblauch, Rosmarin) sowie ihre Mischungen, mit NaCl-Lösung hergestellt. Gleichzeitig wurden pH und spez. Leitfähigkeit der Lösungen in Abhängigkeit von Art und Masseanteil der Gewürze gemessen.The influence of water-space spice extracts on the corrosion of aluminum in sodium chloride solution was investigated. Model solutions of spice extracts (paprika, pepper, garlic, rosemary) and mixtures in sodium chloride solution were prepared for the determination of corrosion current versus corrosion potential of aluminum. Simultaneously, pH and conductance of the solutions as a function of each spice and its concentration were measured.  相似文献   
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7.
Gangliosides serve as antitumor therapy targets and aberrations in their composition strongly correlate with tumor growth and invasiveness. Anaplastic ganglioglioma is a rare, poorly characterized, malignant neuronal–glial tumor type. We present the first comparative characterization of ganglioside composition in anaplastic ganglioglioma vs. peritumoral and healthy brain tissues by combining mass spectrometry and thin-layer chromatography. Anaplastic ganglioglioma ganglioside composition was highly distinguishable from both peritumoral and healthy tissue despite having five to six times lower total content. Ten out of twelve MS-identified ganglioside classes, defined by unique glycan residues, were represented by a large number and considerable abundance of individual species with different fatty acid residues (C16–C24) in ceramide portions. The major structurally identified class was tumor-associated GD3 (>50%) with 11 species; GD3 (d18:1/24:0) being the most abundant. The dominant sphingoid base residue in ganglioside ceramides was sphingosine (d18:1), followed by eicosasphingosine (d20:1). The peritumoral tissue ganglioside composition was estimated as normal. Specific ganglioside composition and large variability of ganglioside ceramide structures determined in anaplastic ganglioglioma demonstrate realistic ganglioside expression patterns and correspond to the profile of high-grade malignancy brain tumors.  相似文献   
8.
An innovative method was developed for production of alginate hydrogel microbeads incorporated with silver nanoparticles (AgNPs) based on electrochemical synthesis followed by electrostatic extrusion. AgNPs were synthesized galvanostatically at different values of AgNO3 concentration in the initial solution (0.5–3.9 mM), current density (5–50 mA cm−2), and implementation time (0.5–10 min). Increase in all of these parameters increased the concentration of AgNPs in alginate solution and was confirmed by TEM analysis and UV–vis spectroscopy. Cyclic voltammetry studies and Fourier transform infrared spectroscopy proved the alginate to be a good capping agent for the electrochemical synthesis of silver nanoparticles, due to coordination bonding between hydroxyl and ether groups, as well as ring oxygen atoms in uronic acid residues of alginate molecules, and Ag nanoparticles. Ag/alginate colloid solution was used for production of uniform hydrogel microbeads (with diameter of 487.75 ± 16.5 μm) by electrostatic extrusion technique. UV–vis spectroscopy confirmed retention and entrapment of AgNPs in microbeads during the production process. Alginate microbeads incorporated with AgNPs are attractive as biocompatible carriers and/or efficient donors of AgNPs as active components especially for potential biomedical applications, which was demonstrated by the antibacterial activity against Staphylococcus aureus.  相似文献   
9.
Nanocrystalline (Y0.7Gd0.3)2O3 powder, synthetised via polymer complex solution method, was compacted into 25 pellets applying high pressures (173-867 MPa) for 30 s that were subsequently sintered at different temperatures (800-1400 °C) for 18 h. The morphology and optical characteristics of the starting powder and prepared ceramic samples were monitored and discussed in order to identify the changes induced with the variations of initial compacting pressure, which influence is often neglected, and with sintering temperature. The grain size tends to decrease significantly with increasing pressure, even when elevated temperatures are used for annealing, while low compacting pressure resulted in grain coarsening and, in some cases, even in anomalous morphology of ceramic samples. Luminescence emission in ceramic samples decays faster than in nanopowders, that is in complete agreement with the grain formation and gradual transformation to the bulk material. Judd-Ofelt intensity parameters and branching ratios were calculated taking into account the difference in effective refractive index for nanopowder and ceramic samples.  相似文献   
10.
Xenogeneic biomaterials Cerbone® and OsteoBiol® are widely used in oral implantology. In dental practice, xenogeneic biomaterial is usually combined with autologous bone to provide bone volume stability needed for long-term dental implants. Magnesium alloy implants dissolve and form mineral corrosion layer that is directly in contact with bone tissue, allowing deposition of the newly formed bone. CSBD heals by intramembranous ossification and therefore is a convenient model for analyses of ostoconductive and osteoinductive properties of different type of biomaterials. Magnesium alloy-enriched biomaterials have not yet been applied in oral implantology. Therefore, the aim of the current study was to investigate biological properties of potentially new bovine xenogeneic biomaterial enriched with magnesium alloy in a 5 mm CSBD model. Osteoconductive properties of Cerabone®, Cerabone® + Al. bone, and OsteoBiol® were also analyzed. Dynamics of bone healing was followed up on the days 3, 7, 15, 21, and 30. Calvary bone samples were analyzed by micro-CT, and values of the bone morphometric parameters were assessed. Bone samples were further processed for histological and immunohistochemical analyses. Histological observation revealed CSBD closure at day 30 of the given xenogeneic biomaterial groups, with the exception of the control group. TNF-α showed high intensity of expression at the sites of MSC clusters that underwent ossification. Osx was expressed in pre-osteoblasts, which were differentiated into mature osteoblasts and osteocytes. Results of the micro-CT analyses showed linear increase in bone volume of all xenogeneic biomaterial groups and also in the control. The highest average values of bone volume were found for the Cerabone® + Mg group. In addition, less residual biomaterial was estimated in the Cerabone® + Mg group than in the Cerabone® group, indicating its better biodegradation during CSBD healing. Overall, the magnesium alloy xenogeneic biomaterial demonstrated key properties of osteoinduction and biodegradidibility during CSBD healing, which is the reason why it should be recommended for application in clinical practice of oral implantology.  相似文献   
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