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131.
Cisplatin (CP) is a conventional chemotherapeutic agent with serious adverse effects. Its toxicity was linked to the stimulation of oxidative stress and inflammation. As a result, this study explored the protective effect of baicalein and alpha-tocopherol in nephrotoxicity induced by cisplatin. Until receiving an intraperitoneal injection of CP (3 mg/kg BW), rats were given baicalein orally 100 mg/kg for seven days or/and a single intraperitoneal injection of α-tocopherol 250 mg/kg. Renal function was tested to explore whether baicalein and α-tocopherol have any beneficial effects; blood urea nitrogen (BUN), serum creatinine, malondialdehyde (MDA) content, antioxidant activity biomarkers and histopathology of renal tissue, oxidative stress biomarkers, inflammatory response markers, and histopathological features of kidney architecture were measured. Cisplatin treatment resulted in extreme renal failure, as measured by high serum creatinine and BUN levels and severe renal changes. Cisplatin therapy resulted in increased lipid peroxidation and decreased glutathione and superoxide dismutase levels, reflecting oxidative stress. Upon treatment with α-tocopherol, baicalein, and combined therapy, there was augmentation in the antioxidant status as well as a reduction in IL-6, NF-κB, TNF, TLR2, and TLR4 and a significant increase in Keap-1 and NRF-2. The combined treatment was the most effective and the nearest to the normal status. These findings suggest that baicalein and α-tocopherol may be useful in preventing cisplatin-induced nephrotoxicity.  相似文献   
132.
In continuation of our previous work, a series of novel thiophene derivatives 4 , 5 , 6 , 8 , 9 , 9a , 9b , 9c , 9d , 9e , 10 , 10a , 10b , 10c , 10d , 10e , 11 , 12 , 13 , 14 , 15 , 16 were synthesized by the reaction of ethyl 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxylate ( 1 ) or 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile ( 2 ) with different organic reagents. Fusion of 1 with ethylcyanoacetate or maleic anhydride afforded the corresponding thienooxazinone derivative 4 and N‐thienylmalimide derivative 5 , respectively. Acylation of 1 with chloroacetylchloride afforded the amide 6 , which was cyclized with ammonium thiocyanate to give the corresponding N‐theinylthiazole derivative 8 . On the other hand, reaction of 1 with substituted aroylisothiocyanate derivatives gave the corresponding thiourea derivatives 9a , 9b , 9c , 9d , 9e , which were cyclized by the action of sodium ethoxide to afford the corresponding N‐substituted thiopyrimidine derivatives 10a , 10b , 10c , 10d , 10e . Condensation of 2 with acid anhydrides in refluxing acetic acid afforded the corresponding imide carbonitrile derivatives 11 , 12 , 13 . Similarly, condensation of 1 with the previous acid anhydride yielded the corresponding imide ethyl ester derivatives 14 , 15 , 16 , respectively. The structures of newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR, MS spectral data, and elemental analysis. The detailed synthesis, spectroscopic data, LD50, and pharmacological activities of the synthesized compounds are reported.  相似文献   
133.
Microbial fuel cells (MFCs) represent a new approach for treating waste water along with electricity production. The present study addressed electricity production from domestic wastewater using a mediator-less double chamber MFC. The electricity production was monitored under different operational conditions for both summer and winter samples. Optimization of the anodic and cathodic chambers resulted in a maximal current of 0.784 and 0.645 mA with the maximal power intensity of 209 and 117 mW/m2 in power duration of 24 h for the summer and winter samples, respectively. Scanning electron microscopy showed that the bacterial biofilm formation on the anode was denser for the summer sample than that when the winter sample was used, so was the total bacterial count. Therefore, samples taken during summer were considered better in electricity production and waste water treatment than those taken during winter basically because of the high microbial load during the hot season. In parallel, there was a decrease in both biological oxygen demand (BOD5) and chemical oxygen demand (COD) values which reached 71.8% and 72.85%, respectively at the end of the operation process for the summer sample, while there was no evident decrease for the winter sample. Optimizing the operating conditions not only increased the potential of using domestic waste water in microbial fuel cells to produce electricity, but also improved the quality of the domestic waste water.  相似文献   
134.
8‐Hydroxyquinolium chloroacetate ( L1 ) was synthesized and characterized. The results suggest that L1 loses ethyl chloroacetate ion on coordination at low pH (2–5) and consequently it behaves as 8‐hydoxyquinoline ( L2 ). Cu2+, Co2+, Pt4+, Pd2+, Au3+, Ag+ and Nd3+ complexes derived from L2 have been synthesized and characterized using spectral, magnetic and thermal measurements. L2 acts as a neutral bidentate ligand in the case of Cu2+, Co2+, Pt4+, Pd2+ and Nd3+ complexes and as a mononegative bidentate ligand in the case of Au3+ and Ag+ complexes. Octahedral geometry is proposed for Cu2+, Co2+ (grey) and Pt4+ complexes and square‐planar for Co2+ (green), Pd2+ and Au3+ complexes. The bond lengths, bond angles, chemical reactivities, binding energies and dipole moments for all compounds were evaluated using density functional theory and molecular electrostatic potential for L1 . Superoxide dismutase radical scavenger‐like activity and cytotoxic activity of the complexes towards HepG2 liver cancer cells has been screened. Cytotoxicity measurements show that Ag+ and Pd2+ complexes have the highest cytotoxic activity while L1 , Cu2+, Co2+ (grey), Co2+ (green), Pt4+ and Nd3+ complexes have no cytotoxic activity. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
135.
New biologically safe thin adsorptive films were synthesised using chitosan/polyacrylamide polymer blend (Ch/PA) via thermal crosslinking technique for the separation of Cu2+ and Pb2+ from aqueous solution and natural water samples. The prepared films were characterised using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and Thermogravimetric analysis (TGA) techniques. Thermo-gravimetric analysis revealed an enhancement in the thermal stability of the prepared thin films with increasing polyacrylamide content. Kinetic and thermodynamic studies were evaluated by batch-type experiments. The obtained results indicated that the adsorption isotherms were well described by Freundlich model, and Ch/PA have adsorption capacities of 177.9 and 126.58 mg.g?1 to Cu2+ and Pb2+, respectively. Under optimum conditions, calculated detection limits were as low as 0.018 and 0.034 μg.L?1 for Cu2+ and Pb2+, respectively, and relative standard deviations of less than 4% for five separate experiments. Moreover, the traditional Lagergren adsorption kinetic model provided the best fitting for the kinetic data. Furthermore, the reusability studies revealed a decrease in the adsorption capacity by about 8% after three adsorption–desorption cycles. The prepared thin films were successfully applied for the separation of Cu2+ and Pb2+ from natural water samples.  相似文献   
136.
Densities (ρ) and viscosities (η) of aqueous 1-methylpiperazine (1-MPZ) solutions are reported at T = (298.15 to 343.15) K. Refractive indices (nD) are reported at T = (293.15 to 333.15) K, and surface tensions (γ) are reported at T = (298.15 to 333.15) K. Derived excess properties, except excess viscosities (Δη), are found to be negative over the entire composition range. The addition of 1-MPZ reduces drastically the surface tension of water. The temperature dependence of surface tensions is explained in terms of surface entropy (SS) and enthalpy (HS). The measured and derived properties are used to probe the microscopic liquid structure of the bulk and surface of the aqueous amine solutions.  相似文献   
137.
In continuation of our previous work, a novel series of steroid derivatives were synthesized and their androgen receptor (AR) antagonist activities and in vivo antiandrogenic properties were evaluated. Twenty-one heterocyclic derivatives containing a cyanopyrane ring fused to a steroidal moiety were conveniently synthesized and screened for their antagonistic, antiandrogen and prostate anticancer activities comparable to that of bicalutamide as the reference control. Some of the compounds exhibited better antagonistic, antiandrogen and prostate anticancer activities than the reference controls. Initially the acute toxicity of the compounds was assayed via the determination of their LD(50). Synthetic steroidal structures fused to a substituted cyanopyrane ring seem to be a promising approach in the search for novel leads for potent antagonistic, antiandrogen and prostate anticancer agents.  相似文献   
138.
Here we report a quantitative comparison of sector field inductively coupled plasma mass spectrometry (ICP-SFMS) and collision/reaction cell inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) for the detection of 90Sr, 137Cs, and 226Ra at ultra-trace levels. We observed that the identification and quantification of radioisotopes by ICP-MS were hampered by spectral (both isobaric and polyatomic ions) and non-spectral (matrix effect) interferences. ICP-QMS has been used to eliminate the isobaric 90Sr/90Zr interference through the addition of O2 into the collision cell as a reactant gas. Zr+ ions were subsequently converted into ZrO+, whereas Sr+ ions were not reactive. In addition, the isobaric interference of 137Ba on 137Cs was eliminated by the addition of N2O gas in the cell, which led to the formation of BaO+ and BaOH+ products, whereas Cs+ remained unreactive. Furthermore, He and H2 were used in the collision/reaction cell to eliminate polyatomic ions formed at m/z 226. A comparison of the results obtained by ICP-SFMS after a chemical separation of Sr from Zr and Cs from Ba was performed. Finally, to validate the developed analytical procedures, measurements of the same samples were performed by γ-ray spectroscopy.  相似文献   
139.
Tutte proved that every 3‐connected graph G on more than 4 vertices contains a contractible edge. We strengthen this result by showing that every depth‐first‐search tree of G contains a contractible edge. Moreover, we show that every spanning tree of G contains a contractible edge if G is 3‐regular or if G does not contain two disjoint pairs of adjacent degree‐3 vertices.  相似文献   
140.
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