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21.
The accumulation of mutations in cancer driver genes, such as tumor suppressors or proto-oncogenes, affects cellular homeostasis. Disturbances in the mechanism controlling proliferation cause significant augmentation of cell growth and division due to the loss of sensitivity to the regulatory signals. Nowadays, an increasing number of cases of liver cancer are observed worldwide. Data provided by the International Cancer Genome Consortium (ICGC) have indicated many alterations within gene sequences, whose roles in tumor development are not well understood. A comprehensive analysis of liver cancer (virus-associated hepatocellular carcinoma) samples has identified new and rare mutations in B-Raf proto-oncogene (BRAF) in Japanese HCC patients, as well as BRAF V600E mutations in French HCC patients. However, their function in liver cancer has never been investigated. Here, using functional analysis and next generation sequencing, we demonstrate the tumorigenic effect of BRAF V600E on hepatocytes (THLE-2 cell line). Moreover, we identified genes such as BMP6, CXCL11, IL1B, TBX21, RSAD2, MMP10, and SERPIND1, which are possibly regulated by the BRAF V600E-mediated, mitogen-activated protein kinases/extracellular signal-regulated kinases (MAPK/ERK) signaling pathway. Through several functional assays, we demonstrate that BRAF L537M, D594A, and E648G mutations alone are not pathogenic in liver cancer. The investigation of genome mutations and the determination of their impact on cellular processes and functions is crucial to unraveling the molecular mechanisms of liver cancer development.  相似文献   
22.
Cyclin-dependent kinases (CDKs) are pivotal mediators and effectors of the DNA damage response (DDR) that regulate both the pathway components and proteins involved in repair processes. Synthetic lethality (SL) describes a situation in which two genes are linked in such a way that the lack of functioning of just one maintains cell viability, while depletion of both triggers cell death. Synthetic lethal interactions involving CDKs are now emerging, and this can be used to selectively target tumor cells with DNA repair defects. In this review, SL interactions of CDKs with protooncogene products MYC, poly (ADP-ribose) polymerase (PARP-1), and cellular tumor antigen p53 (TP53) are discussed. The individual roles of each of the SL partners in DDR are described.  相似文献   
23.
This article presents a new lake district in Southern Poland created as a result of human activity in the Upper Silesian region. The area has been named the Upper Silesian Anthropogenic Lake District. The lake density of the Lake District as delineated by the authors (with an area of 6766 km2) is 2.74%. It includes 4773 water bodies of various origins – reservoirs retained by dams, flooded mineral workings, water bodies formed in subsidence basins and hollows, levee ponds, residual water bodies following river regulation and other water bodies. These are located in urban‐industrial, rural‐agricultural or quasi‐natural areas. The hydrochemical diversity of water bodies is conditioned by their origin, location in the catchment and function. Studies have shown the widespread occurrence of eutrophication processes in limnic waters within the Lake District. The diverse origin and hydrochemical properties of water bodies within the Upper Silesian Anthropogenic Lake District make it special among other anthropogenic lake districts.  相似文献   
24.
4-(5-methyl-1,3,4-thiadiazole-2-yl) benzene-1,3-diol (C1) and 4-[5-(naphthalen-1-ylmethyl)-1,3,4-thiadiazol-2-yl] benzene1,3-diol (NTBD) are representative derivatives of the thiadiazole group, with a high antimycotic potential and minimal toxicity against normal human fibroblast cells. The present study has proved its ability to synergize with the antifungal activity of AmB. The aim of this work was to evaluate the cytotoxic effects of C1 or NTBD, alone or in combination with AmB, on human renal proximal tubule epithelial cells (RPTECs) in vitro. Cell viability was assessed with the MTT assay. Flow cytometry and spectrofluorimetric techniques were used to assess the type of cell death and production of reactive oxygen species (ROS), respectively. The ELISA assay was performed to measure the caspase-2, -3, and -9 activity. ATR-FTIR spectroscopy was used to evaluate biomolecular changes in RPTECs induced by the tested formulas. The combinations of C1/NTBD and AmB did not exert a strong inhibitory effect on the viability/growth of kidney cells, as evidenced by the negligible changes in the apoptotic/necrotic rate and caspase activity, compared to the control cells. Both NTBD and C1 displayed stronger anti-oxidant activity when combined with AmB. The relatively low nephrotoxicity of the thiadiazole derivative combinations and the protective activity against AmB-induced oxidative stress may indicate their potential use in the therapy of fungal infections.  相似文献   
25.
Methods of electron microscopy and X-ray diffraction have been used to investigate structural and phase transformations in the aluminum alloy of grade A2024 (Al–4.5 Cu–1.37 Mg–0.61 Mn–0.07 Si–0.27 Fe–0.02 Zn–0.02 Ti (wt %)) after aging and deformation by shear under high quasi-static pressure. It has been shown that the combination of two-stage aging with megaplastic deformation leads to the refinement of the structure to a nanolevel and to strengthening of the alloy (to an increase in the microhardness to 3000 MPa). The values of true deformation at which the deformation-induced dissolution of the particles of the strengthening S phase occurs have been determined.  相似文献   
26.
The blends of pectin (PEC) and poly(vinyl alcohol) (PVA) at different components ratios were prepared by mixing in water. Thin polymeric films of PEC/PVA blends and pure polymers were obtained by casting method. All samples were then artificially aged using Suntest apparatus (Atlas) up to 780 h. The changes in chemical structure during sample ageing have been monitored by infrared and ultraviolet‐visible absorption spectroscopies. The first stage of weathering (up to ~ 300 h) was very slow and alteration of chemical structure was negligible in all samples. Prolonged ageing (>300 h) caused more significant degradation processes. FTIR spectra exhibited the highest changes in hydroxyl and carbonyl band ranges indicating the efficient photooxidation of macromolecules. The mechanisms of the observed processes have been discussed. It was found that PVA undergoes faster photoxidative degradation than pectin aged at the same conditions. The PEC/PVA blends exhibited the improved resistance to weathering comparing with both polymers aged individually. Mutual stabilization effect can be explained by intermolecular interactions between PEC and PVA confirmed by spectroscopic methods. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
27.
The impact of seminal plasma components on the fertilization outcomes in humans is still under question. The increasing number of couples facing problems with conception raises the need for predictive biomarkers. Detailed understanding of the molecular mechanisms accompanying fertilization remains another challenge. Carbohydrate–protein recognition may be of key importance in this complex field. In this study, we analyzed the unique glycosylation pattern of seminal plasma proteins, the display of high-mannose and hybrid-type oligosaccharides, by means of their reactivity with mannose-specific Galanthus nivalis lectin. Normozoospermic infertile subjects presented decreased amounts of lectin-reactive glycoepitopes compared to fertile donors and infertile patients with abnormal semen parameters. Glycoproteins containing unveiled mannose were isolated in affinity chromatography, and 17 glycoproteins were identified in liquid chromatography-tandem mass spectrometry with electrospray ionization. The N-glycome of the isolated glycoproteins was examined in matrix-assisted laser desorption ionization mass spectrometry. Eleven out of 27 identified oligosaccharides expressed terminal mannose residues, responsible for lectin binding. We suggest that lowered content of high-mannose and hybrid type glycans in normozoospermic infertile patients may be associated with impaired sperm protection from preterm capacitation and should be considered in the search for new infertility markers.  相似文献   
28.
The one-step metal promoted reaction between salicylaldehyde and 4-methyl-1,3-phenylenediamine in the presence of lanthanum(III) or gadolinium(III) nitrate yields new salicylaldimine complexes containing N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine as a result of the [2 + 1] Schiff base condensation. The crystal structure of the gadolinium complex reveals a dinuclear species with four unionized ligands coordinating in the monodentate and bridging bidentate fashion, using exclusively the oxygens as donor atoms with the nitrogen atoms not being involved in coordination. The coordination number of nine is achieved by involving three bidentate nitrate counterions in the coordination sphere.  相似文献   
29.
30.
The purpose of this article is to present energetic properties of surface Ti6Al4V titanium as well as surface EN-AW-2017A(PA6) aluminum alloy layers. Values of surface free energy after selected mechanical operations and ozonation were compared. In addition, the influence of different values of ozone concentration on surface layer energetic activation was analyzed. Dispersive and polar components of surface free energy were of particular concern. Comparative evaluation of shearing strength of Ti6Al4V titanium and EN-AW-2017A(PA6) aluminum alloy single-lap adhesive bonded joints were presented. Results can be used as pro-ecological methods of titanium and aluminum alloys preparing for applications where adhesive phenomenon is important.  相似文献   
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