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1.
The use of nanomaterials rationally engineered to treat cancer is a burgeoning field that has reported great medical achievements. Iron-based polymeric nano-formulations with precisely tuned physicochemical properties are an expanding and versatile therapeutic strategy for tumor treatment. Recently, a peculiar type of regulated necrosis named ferroptosis has gained increased attention as a target for cancer therapy. Here, we show for the first time that novel iron oxide nanoparticles coated with gallic acid and polyacrylic acid (IONP–GA/PAA) possess intrinsic cytotoxic activity on various cancer cell lines. Indeed, IONP–GA/PAA treatment efficiently induces ferroptosis in glioblastoma, neuroblastoma, and fibrosarcoma cells. IONP–GA/PAA-induced ferroptosis was blocked by the canonical ferroptosis inhibitors, including deferoxamine and ciclopirox olamine (iron chelators), and ferrostatin-1, the lipophilic radical trap. These ferroptosis inhibitors also prevented the lipid hydroperoxide generation promoted by the nanoparticles. Altogether, we report on novel ferroptosis-inducing iron encapsulated nanoparticles with potent anti-cancer properties, which has promising potential for further in vivo validation.  相似文献   
2.
A new aroyl-hydrazone, 2-pyridine carboxaldehyde-derived hydrazone ligand and its cobalt(II) (1) and vanadium(V) (2) complexes were prepared. The structures of these compounds were investigated using elemental analysis, spectral (IR, UV), and X-ray diffraction measurements. The electrochemical properties of the complexes were studied by cyclic voltammetry. The hydrazone ligand acted as tridentate and coordinated to vanadium and cobalt via N-imine, N-pyridine, and O-benzohydrazide atoms. The Co(II) complex crystallizes in the monoclinic system, space group P21/c, and has a binuclear structure. Chloride ions behave as the linking bridge and a tridentate hydrazine ligand HL and water as the terminal capping ligands. The central Co(II) ion has distorted octahedral geometry. The vanadium(V) complex crystallizes in the monoclinic crystal system, space group P21/n, and can be described as having highly distorted trigonal-bipyramidal coordination. The geometries and electronic properties of the complexes were also obtained using DFT and TD-DFT calculations.  相似文献   
3.
A facile and efficient method for one-pot conversion of alcohols into azides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, alcohols are refluxed with a mixture of NaN3, TsIm and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in DMF affording the corresponding alkyl azides in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°.  相似文献   
4.
A very mild and highly efficient synthesis of some novel 1H‐1,2,3‐triazolyl carboacyclic nucleosides via a ‘Click’ Huisgen cycloaddition of N‐propargyl nucleobases and azido alcohols using Cu/aminoclay/reduced graphene oxide nanohybrid (Cu/AC/r‐GO nanohybrid) as nanocatalyst is described. The preparation and characterization of Cu/AC/r‐GO nanohybrid are discussed. This catalyst was characterized by X‐ray diffraction, FT‐IR, TEM, and energy‐dispersive analysis of X‐ray techniques. Cu/AC/r‐GO nanohybrid is a stable and highly efficient heterogeneous nanocatalyst that can be easily prepared, used, and restored from the reaction mixture by simple filtration, and reused for many consecutive trials without significant decrease in activity.  相似文献   
5.
Degradation of Acid Orange 7 (AO7) as a model azo dye was investigated in a recirculating pilot fluidized-bed reactor by a Fenton-like process using natural magnetite (NM) and potassium persulfate (K2S2O8). Scanning electron microscopy was performed to characterize the magnetite sample. The heterogeneous Fenton-like process (NM/\({\text{S}}_{2} {\text{O}}_{8}^{2 - }\)) is a modified method owing to its enhanced mass transfer. It can be operated reliably and simply by reducing the produced iron oxide sludge in the conventional Fenton process. Degradation efficiency (DE %) of AO7 by NM/ \({\text{S}}_{2} {\text{O}}_{8}^{2 - }\) process was affected by operational parameters. The DE % of 75 % was obtained for the AO7 treatment (15 mg/L) at the desired conditions, such as pH 5, 0.2 mM \({\text{S}}_{2} {\text{O}}_{8}^{2 - }\), and 0.5 g/L NM after 120 min of reaction time. The dye degradation rate in all the experiments followed the pseudo-second-order kinetic with high correlation coefficients (R 2 ≥ 0.98). The low released iron concentration, successive reusability at milder pH and the recirculation mode with the proper mixing are the significant advantages of the NM/\({\text{S}}_{2} {\text{O}}_{8}^{2 - }\) process.  相似文献   
6.
Cold expansion is a useful process for imposing compressive residual stresses around the holes in riveted and bolted connections. These stresses increase the fatigue life of holed parts. Distribution and amount of exerted residual stress dependent on various parameters as material, distance of adjacent holes, hole diameter, cold expansion ratio and plate thickness. In this study, experimental and numerical results for two different aluminum alloys and various holes distances are investigated and compared. Effects of mentioned parameters on the residual stress are studied.  相似文献   
7.
A facile and highly efficient method for one-pot Beckmann rearrangement of ketoximes into N-substituted amides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, ketoximes are refluxed with TsIm and Cs2CO3 in the presence of SiO2 as a recyclable catalyst in DMF affording the corresponding amides in high yields. This methodology is highly efficient and regioselective for various structurally diverse ketoximes including symmetrical and unsymmetrical as well as cyclic oximes. The results of quantum mechanical studies used to rationalize the experimental outcomes are discussed.  相似文献   
8.
A facile and simple protocol for the 1,3‐dipolar cycloaddition of organic azides with terminal alkynes catalyzed by doped nano‐sized Cu2O on melamine? formaldehyde resin (nano‐Cu2O? MFR) as a new and convenient heterogeneous catalyst is described. In this method, ‘click’ cycloaddition of various structurally diverse β‐azido alcohols and alkynes in the presence of nano‐Cu2O? MFR in H2O/THF 1 : 2 furnished the corresponding 1,4‐disubstituted 1H‐1,2,3‐triazole adducts 1a – 1o in good to excellent yields at room temperature (Scheme and Table 3). The nano‐Cu2O? MFR was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), inductively coupled plasma (ICP) analysis, and FT‐IR. The nano‐Cu2O? MFR could be easily recovered and recycled from the reaction mixture and reused for many consecutive trials without significant decrease in activity (Table 4). The in vitro antibacterial activities of all synthesized compounds were tested on several Gram‐positive and/or Gram‐negative bacteria (Table 5). The results demonstrate the promising antibacterial activity for some of the synthesized compounds.  相似文献   
9.
A facile and efficient method for dehydration of aldoximes into nitriles using N-(p-toluenesulfonyl) imidazole (TsIm) is described. In this method, aldoximes were refluxed with TsIm in the presence of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU) in dimethylformamide (DMF) to afford the corresponding nitriles in good yields. This methodology is highly efficient for various structurally diverse aldoximes including aromatic, heteroaromatic, and aliphatic oximes. A plausible mechanism for the conversion of aldoxime into nitriles using TsIm/DBU is explained.  相似文献   
10.
Journal of Radioanalytical and Nuclear Chemistry - In this study, optimized preparation, quality control, cell assessments and biostribution of 188Re-HYNIC-PSMA in normal rats and tumor bearing...  相似文献   
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