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71.
In this study, for the first time, calcium oxide (CaO)/polylactic acid nanoscaffolds were synthesized by co‐precipitation assistant reverse micelles method. The physical and chemical (physicochemical) properties of the structures as dental resin composites were also studied. Nanocomposite materials as primary and basic dental compounds can be conveniently applied as dental filling materials with a high esthetic quality. In this research nanoscaffolds act as a bed for nanoparticles and improve the mechanical and chemical (mechanochemical) properties, CaO nanoparticles were loading in polylactic acid nanoscaffold as a bioactivity polymer for usage in the dental resin composites. Mechanical properties of the dental resin composite containing CaO/polylactic acid nanoscaffold were calculated: the flexural strength (137.2 MPa), modulus (12.9GPa) and compressive strength (344.2 MPa). Potential of the basic nanoparticle and the products were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), dynamic light scattering (DLS), ultraviolet‐visible spectroscopy (UV‐visible) and atomic force microscopy (AFM) showed the size of the optimized nanostructures was about 85 to 120 nm. According to TGA results of polylactic acid nanofibers with thermal stability below 300°C these high thermal stability materials can be used as dental resin composites. 相似文献
72.
Mehdi Adib Fariba Peytam Reihaneh Shourgeshty Maryam Mohammadi-Khanaposhtani Mehdi Jahani Somaye Imanparast Mohammad Ali Faramarzi Bagher Larijani Ali Akbar Moghadamnia Ensieh Nasli Esfahani Fatemeh Bandarian Mohammad Mahdavi 《Bioorganic & medicinal chemistry letters》2019,29(5):713-718
Twenty three fused carbazole–imidazoles 6a–w were designed, synthesized, and screened as new α-glucosidase inhibitors. All the synthesized fused carbazole-imidazoles 6a-w were found to be more active than acarbose (IC50?=?750.0?±?1.5?µM) against yeast α-glucosidase with IC50 values in the range of 74.0?±?0.7–298.3?±?0.9?µM. Kinetic study of the most potent compound 6v demonstrated that this compound is a competitive inhibitor for α-glucosidase (Ki value?=?75?µM). Furthermore, the in silico studies of the most potent compounds 6v and 6o confirmed that these compounds interacted with the key residues in the active site of α-glucosidase. 相似文献
73.
74.
Soltani Mehdi Badzohreh Gholamreza Mirzargar Saed Farhangi Mehrdad Shekarabi Pezhman Hosseini Lymbery Alan 《Probiotics and antimicrobial proteins》2019,11(3):765-773
Probiotics and Antimicrobial Proteins - Growth behavior and production of short-chain fatty acid (SCFA) of two probiotics, Pediococcus acidilactici and Lactococcus lactis, each at... 相似文献
75.
Transactivation of epidermal growth factor receptor (EGFR) is a well-documented mechanism by which vasoactive peptides and H2O2 elicit their cellular responses. However, a role for the insulin-like growth factor type-1 receptor (IGF-1R) transactivation in mediating the effects of angiotensin II (Ang II) and H2O2 in vascular smooth muscle cells from different artery types have also been recently recognized. By using a series of pharmacological inhibitors of various growth factor receptor tyrosine kinases and a direct analysis of the phosphorylation status of the beta-subunit of IGF-1R, a requirement of this growth factor receptor in Ang II and H2O2 response has been demonstrated. This review discusses some of the studies that highlight the importance of IGF-1R transactivation in mediating Ang II- and H2O2-induced mitogen-activated protein kinase and protein kinase B signaling pathways. 相似文献
76.
Yousefi R Imani M Ardestani SK Saboury AA Gheibi N Ranjbar B 《Acta biochimica et biophysica Sinica》2007,39(10):795-802
Calprotectin, a heterodimeric complex belonging to the S 100 protein family, has been found predominantly in the cytosolic fraction of neutrophils. In the present study, human calprotectin was purified from neutrophils using two-step ion exchange chromatography. The purified protein was used for circular dichroism study and fluorescence analysis in the presence of calcium and zinc at physiological concentrations, as well as for assessment of its inhibitory activity on the K562 leukemia cell line. The thermal stability of the protein at pH 7.0 (physiological pH) and 8.0 (similar to intestinal pH) was also compared. The results of cell proliferation analysis revealed that human calprotectin initiated growth inhibition of the tumor cells in a dose- dependent manner. The intrinsic fluorescence emission spectra of human calprotectin (50 ktg/ml) in the presence of calcium and zinc ions show a reduction in fluorescence intensity, reflecting a conformational change within the protein with exposure of aromatic residues to the protein surface that is important for the biological function of calprotectin. The far ultraviolet-circular dichroism spectra of human calprotectin in the presence of calcium and zinc ions at physiological concentrations show a decrease in the m-helical content of the protein and an increase in [3- and other structures. Our results also show that increasing the pH level from 7.0 to 8.0 leads to a marked elevation in the thermal stability of human calprotectin, indicating a significant role for pH in the stability of calprotectin in the gut. 相似文献
77.
Lanquar V Kuhn L Lelièvre F Khafif M Espagne C Bruley C Barbier-Brygoo H Garin J Thomine S 《Proteomics》2007,7(5):750-754
An important goal for proteomic studies is the global comparison of proteomes from different genotypes, tissues, or physiological conditions. This has so far been mostly achieved by densitometric comparison of spot intensities after protein separation by 2-DE. However, the physicochemical properties of membrane proteins preclude the use of 2-DE. Here, we describe the use of in vivo labeling by the stable isotope 15N as an alternative approach for comparative membrane proteomic studies in plant cells. We confirm that 15N-metabolic labeling of proteins is possible and efficient in Arabidopsis suspension cells. Quantification of 14N versus 15N MS signals reflects the relative abundance of 14N and 15N proteins in the sample analyzed. We describe the use of 15N-metabolic labeling to perform a partial comparative analysis of Arabidopsis cells following cadmium exposure. By focusing our attention on plasma membrane proteins, we were able to confidently identify proteins showing up to 5-fold regulation compared to unexposed cells. This study provides a proof of principle that 15N-metabolic labeling is a useful technique for comparative membrane proteome studies. 相似文献
78.
79.
International Microbiology - Acanthamoeba spp. and Salmonella share common habitats, and their interaction may influence the biofilm-forming ability of Salmonella. In this study, biofilm formation... 相似文献
80.
Elham Safarzadeh Shahryar Hashemzadeh Pascal H.G. Duijf Behzad Mansoori Vahid Khaze Ali Mohammadi Tohid Kazemi Mehdi Yousefi Milad Asadi Hamed Mohammadi Farhad Babaie Behzad Baradaran 《Journal of cellular physiology》2019,234(4):3515-3525
Evading immune destruction is a hallmark of cancer. Myeloid-derived suppressor cells (MDSCs), a heterogeneous population of myeloid immune cells, are thought to foster the establishment of an immunosuppressive tumor microenvironment, but it remains unclear how. This study aims to determine the levels of circulating MDSCs and their subpopulations and test their immunosuppressive functions in patients with breast cancer (BC). We analyzed the fractions of MDSCs in freshly isolated peripheral blood mononuclear cells of patients with BC and healthy donors using flow cytometry. Circulating MDSCs were further phenotyped using fluorescently labeled antihuman monoclonal antibodies. Coculture experiments revealed the effects of MDSCs on CD3+ T cell response. Moreover, we correlated circulating MDSC levels with clinicopathological features of patients with BC. We show that the fraction of HLA-DR – CD33 + MDSCs in peripheral blood is about 10-fold higher in patients with BC than in healthy control individuals. The levels of all MDSC subpopulations, including monocytic and granulocytic MDSCs, are significantly elevated. Coculture experiments of purified HLA-DR – CD33 + MDSCs and CD3 + T cells demonstrate that T cell proliferation is more effectively inhibited by BC patient-derived MDSCs than by healthy control MDSCs. Moreover, increased circulating MDSC levels robustly associate with advanced BC stage and positive lymph node status. By being more abundant and more effective T cell suppressors, BC patient-derived circulating MDSCs exert a dual immunosuppressive effect. Our findings pave the way to develop novel diagnostic and immunotherapeutic strategies, aimed at detecting and inhibiting MDSCs in patients with BC. 相似文献