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21.
Wound healing and skin tissue regeneration remain the most critical challenges faced by medical professionals. Titanium(IV) oxide-based materials were proposed as components of pharmaceutical formulations for the treatment of difficult-to-heal wounds and unsightly scarring. A gallic acid-functionalized TiO2 nanomaterial (TiO2-GA) was obtained using the self-assembly technique and characterized using the following methods: scanning electron microscopy (SEM), transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), X-ray powder diffraction (XRPD), infrared spectroscopy (IR), Raman spectroscopy and thermogravimetry (TG). Additionally, physicochemical and biological tests (DPPH assay, Microtox® acute toxicity test, MTT assay) were performed to assess antioxidant properties as well as to determine the cytotoxicity of the novel material against eukaryotic (MRC-5 pd19 fibroblasts) and prokaryotic (Staphylococcus aureus, Escherichia coli, Candida albicans, Aliivibrio fischeri) cells. To determine the photocytotoxicity of the material, specific tests were carried out with and without exposure to visible light lamps (425 nm). Following the results, the TiO2-GA material could be considered an additive to dressings and rinsing suspensions for the treatment of difficult-to-heal wounds that are at risk of bacterial infections.  相似文献   
22.
Nanoindentations and the Raman spectroscopy measurements were carried out on the (001) surface of undoped and S-doped InP crystal. The samples were indented with the maximum load ranging from 15 mN to 100 mN. The phase transition B3→B1 was not confirmed by spectroscopic experiments, indicating a plastic deformation mechanism governed by dislocations activity. Increasing the maximum indentation load shifts and the longitudinal and transverse optical Raman bands to lower frequencies reveals a reduction in the elastic energy stored in the plastic zone right below the indentation imprint. Mechanical experiments have shown that a shift in Raman bands occurs alongside the indentation size effect. Indeed, the hardness of undoped and S-doped InP crystal decreases as a function of the maximum indentation load.  相似文献   
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In this work, possible effective mechanisms of cromolyn, atorvastatin and lovastatin on the cytotoxicity of Aβ(31–35) and Aβ(25–35) peptides were investigated by classical molecular dynamics and well-tempered metadynamics simulations. The results demonstrate that all the drugs affect the behavior of the peptides, such as their ability to aggregate, and alter their secondary structures and their affinity to a particular drug. Our findings from the computed properties suggest that the best drug candidate is lovastatin. This medicine inhibits peptide aggregation, adsorbs the peptides on the surface of the drug clusters, changes the secondary structure and binds to MET35, which has been seen as the reason for the toxicity of the studied peptide sequences. Moreover, lovastatin is the drug which previously has demonstrated the strongest ability to penetrate the blood–brain barrier and makes lovastatin the most promising medicine among the three investigated drugs. Atorvastatin is also seen as a potential candidate if its penetration through the blood–brain barrier could be improved. Otherwise, its properties are even better than the ones demonstrated by lovastatin. Cromolyn appears to be less interesting as an anti-aggregant from the computational data, in comparison to the two statins.

In this work, possible effective mechanisms of cromolyn, atorvastatin and lovastatin on the cytotoxicity of Aβ(31–35) and Aβ(25–35) peptides were investigated by classical molecular dynamics and well-tempered metadynamics simulations.  相似文献   
24.
Adhesive joints are widely used in the construction of machines and motor vehicles. Manufacturers replace them with the welding and spot-welding methods due to the lack of damage to the material structure in the joint area. Moreover, it is aimed at reducing the weight of vehicles and producing elements with complex shapes. Therefore, additive manufacturing technology has been increasingly used in the production stage. This fact has not only changed the view on the possibilities of further development of the production technology itself, but it has also caused an intense interest among a greater number of companies in the advantages of structural optimization. There is a natural relationship between these two areas in the design and production, allowing for almost unlimited possibilities of designing new products. The main goal of the research described in this article was to determine the correlation between the strength of the adhesive joint of elements produced using additive technology and the parameters of the ultrasonic wave propagating in the area of the adhesive bond. The tests were carried out on samples made of AlSiMg0.6 material and a structural adhesive. Strength tests were performed to determine the shear force which damaged the joint. Furthermore, an ultrasonic echo technique enabling the determination of a nondestructive measure of the quality and strength of the joint was developed. The samples of the adhesive joints had a strength of about 18.75–28.95 MPa, which corresponded to an ultrasonic measure range of 4.6–7.8 dB. The determined regression relationship had a coefficient of determination at the level of 0.94. Additional ultrasonic tests of materials made with the additive technology confirmed its different acoustic properties in relation to aluminum produced with the standard casting or extrusion process. Designated dependence combining the mechanical strength and the decibel difference between the first and second impulses from the bottom of the joint may constitute the basis for the development of a nondestructive technique for testing the strength of adhesive joints.  相似文献   
25.
Cervical cancer is one of the leading causes of death among women suffering from tumors. Current treatment options are insufficient. Here, we investigated the MET receptor as a potential molecular target in advanced cervical cancer. Downregulation of MET receptor expression via RNA interference in different cervical carcinoma cell lines dramatically decreased tumor growth and forced tumor differentiation in vivo. MET receptor silencing also led to a dramatic decrease in cell size and a decrease in proliferation rate under normal and stress conditions. MET receptor downregulation also resulted in decreased cyclin D1 and c-myc levels but did not increase apoptosis. Subsequent experiments showed that downregulation of the MET receptor decreased the expression of a key regulator of the epithelial-to-mesenchymal transition, SLUG. and increased the expression of E-cadherin, a hallmark of the epithelial phenotype. Moreover, MET downregulation impairs expression and signaling of CXCR4 receptor, responsible for invasive phenotype.Taken together, our results strongly suggest that the MET receptor influences the oncogenic properties of cervical carcinoma cells in vitro and in vivo. These findings highlight a unique role of the MET receptor in cervical carcinoma cells and indicate the MET receptor as a potential therapeutic target for advanced cervical carcinoma.  相似文献   
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Journal of Thrombosis and Thrombolysis - According to guidelines, it is recommended to give P2Y12 inhibitors (preferably ticagrelor or prasugrel) at the time of first medical contact in patients...  相似文献   
28.
Splenectomy is considered standard surgical therapy in hereditary spherocytosis. The procedure is indicated in patients with severe anemia, recurrent hemolytic, and aplastic crises. The aim of the study was to assess treatment outcomes in patients with hereditary spherocytosis who underwent total or partial laparoscopic splenectomy. Fifteen patients aged 4–17 yr underwent laparoscopic splenectomy from 2009 to 2012. Partial and total splenectomies were performed (five and 10 children, respectively). Hematologic parameters, liver function tests, and splenic volume before and after the surgery were analyzed retrospectively. Total follow‐up was 1–30 months. Hospitalization and operating time were similar in both groups. In partial splenectomy group, branches of splenic arteries gave better blood supply than short gastric vessels. In both groups, hematologic parameters were improved. Postoperative markedly elevated platelet count was maintained up to 6 months, and after that, platelet count gradually decreased to normal values. Bilirubin level was decreased in early postoperative period; however, it increased later to achieve levels lower than in preoperative period. No severe general infections were observed in both groups. Laboratory parameters (hemoglobin and bilirubin concentrations and RBC) after the surgery improved in all patients, and the effect was maintained during 12 months of follow‐up. Platelet count increased significantly after the surgery and was maintained at high levels during the next 6 months. However, it returned to preoperative levels within a year after the surgery. Our study showed that partial splenectomy was not inferior to total splenectomy. However, full assessment requires longer follow‐up and larger group of patients.  相似文献   
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