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- Author or Editor: H. M. Liu x
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Abstract
Objective
The present report evaluates the protective effects of luteolin against diabetic retinopathy (DR).
Materials and methods
Diabetes was induced in rats by i.p. administration of 60 mg/kg of streptozotocin (STZ), followed by treatment with luteolin for 4 weeks. The effects of luteolin were determined based on the blood glucose and cytokine levels, and parameters of oxidative stress in retinal tissue of DR rats. The diameter of retinal vessels was estimated by fundus photography. A Western blot assay was used to determine the expression of apoptotic proteins and Nod-like receptor 3 (NLRP3) pathway proteins in the retina of DR rats. A molecular docking study was performed to evaluate the interaction between luteolin and NLRP3.
Results
The level of blood glucose was reduced in the luteolin-treated group compared with the DR group. Reductions in cytokines and oxidative stress were observed in the retinal tissues of the luteolin-treated group relative to the DR group. Moreover, treatment with luteolin reduced the expression of NLRP1, NOX4, TXNIP, and NLRP3 proteins, and ameliorated the altered expression of apoptotic proteins in the retina of DR rats.
Conclusion
In conclusion, luteolin prevents retinal apoptosis in DR rats by regulating the NLRP/NOX4 signalling pathway.
Abstract
In this paper, a brief survey of hydrogen production methods is presented with a focus on S-I cycle. Based on heat duty data of sulfuric acid decomposition in S-I cycle, optimization models are developed to explore the minimum utility consumption and the minimum number of heat exchangers. Finally an optimal heat exchanger network for S-I thermochemical cycle is defined by a mixed integer optimization model.
Abstract
The complex of [Tb2(o-MBA)6(PHEN)2] (o-MBA: o-methylbenzoate and PHEN:1,10-phenanthroline) were synthesized and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [Tb2(o-MBA)6(PHEN)2] in dynamic nitrogen atmosphere was investigated by TG-DTG techniques. The thermal decomposition process of the [Tb2(o-MBA)6(PHEN)2] occurred in three consecutive stages at Tp 294, 427 and 512C. The kinetic parameters and mechanisms of first decomposition stage from analysis of the TG-DTG curves were obtained by the Malek method.
Abstract
The thermal decomposition of Eu2(BA)6(bipy)2 (BA=C2H5N– 2, benzoate; bipy=C10H8N2, 2,2'-bipyridine)and its kinetics were studied under the non-isothermal condition by TG-DTG, IR and SEM methods. The kinetic parameters were obtained from analysis of the TG-DTG curves by the Achar method, the Madhusudanan-Krishnan-Ninan (MKN) method, the Ozawa method and the Kissinger method. The most probable mechanism function was suggested by comparing the kinetic parameters. The kinetic equation for the first stage can be expressed as: dα/dt=Aexp(–E/RT)3(1–α)2/3.
Abstract
The uranium(VI) accumulation was studied in detail by using the biomass of mangrove endophytic fungus Fusarium sp.#ZZF51 from the South China Sea. The uranium(VI) biosorption process onto the tested fungus powders was optimized at pH 4.0, adsorption time 60 min, and uranium(VI) initial concentration 50 mg L−1 with 61.89% of removal efficiency. According to Fourier transform infrared spectra for the tested fungus before and after loaded with uranium(VI), the results showed that both of hydroxyl and carboxyl groups acted as the important roles in the adsorption process. In addition, the experimental data were analyzed by using parameter and kinetic models, and it was obtained that the Langmuir isotherm model and the pseudo-second-order kinetic model provided better correlation with the experimental data for adsorption of uranium(VI).
Abstract
Although the use of aspirin has substantially reduced the risks of cardiovascular events and death, its potential mechanisms have not been fully elucidated. In a previous study, we found that aspirin triggers cellular autophagy. In the present study, we aimed to determine the protective effects of aspirin on human coronary artery endothelial cells (HCAECs) and explore its underlying mechanisms. HCAECs were treated with oxidized low-density lipoprotein (ox-LDL), angiotensin II (Ang-II), or high glucose (HG) with or without aspirin stimulation. The expression levels of endothelial nitric oxide (NO) synthase (eNOS), p-eNOS, LC3, p62, phosphor-nuclear factor kappa B (p-NF-κB), p-p38 mitogen-activated protein kinase (p-p38 MAPK), and Beclin-1 were detected via immunoblotting analysis. Concentrations of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were measured via ELISA. NO levels were determined using the Griess reagent. Autophagic flux was tracked by tandem mRFP-GFP-tagged LC3. Results showed that aspirin increased eNOS level and reduced injury to the endothelial cells (ECs) caused by ox-LDL, Ang-II, and HG treatment in a dose-dependent manner. Aspirin also increased the LC3II/LC3I ratio, decreased p62 expression, and enhanced autophagic flux (autophagosome and autolysosome puncta) in the HCAECs. p-NF-κB and p-p38 mitogen-activated protein kinase inhibition, sVCAM-1 and sICAM-1 secretion, and eNOS activity promotion by aspirin treatment were found to be dependent on Beclin-1. These results suggested that aspirin can protect ECs from ox-LDL-, Ang-II-, and HG-induced injury by activating autophagy in a Beclin-1-dependent manner.
Abstract
Samarium-153-EDTMP (ethylene diamine tetramethylene phosphonate), for its promising biological properties, has been proved as a palliating therapeutic agent for boné cancer in human beings. In this article, we present the results on synthesis and structure analysis of Samarium-153-EDTMP. In a basic medium,153Sm-EDTMP can be readily prepared with a complexing yield not less than 98%, and it is confirmed that the ratio of the ligand to Sm is 1
1, and the charge of153Sm-EDTMP is negative two.
Stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most serious diseases of wheat ( Triticum aestivum L.) worldwide. Of 94 Triticum durum/Aegilops tauschii synthetic wheat accessions tested, CI142 (Garza/Boy// Ae. squarrosa 271) was found to be resistant to 6 Chinese PST races. The resistance to stripe rust in CI142 was proven to be controlled by a single dominant gene, tentatively designated YrC142 . Gene postulation showed that the pathogenic specificity of CI142 is different from 21 other lines possessing known resistance genes, such as Yr10, Yr15, Yr24 , and Yr26 , located on chromosome 1B. Bulked segregant analysis (BSA) and F 2 segregation analysis of the CI142/Mingxian 169 cross were used to analyse the SSR markers linked to YrC142 . Five SSR markers were found to be closely associated with YrC142 in the order Xwmc419-YrC142-Xgwm273, Xbarc187-Xgwm18-Xwmc626 , in which the relative genetic distances of these SSR loci to the gene YrC142 were 5.4, 0.8, 0.8, 1.0, and 2.4 cM, respectively. Two SSR markers ( Xgwm273 −162 and Xgwm18 −168 ) distinguished YrC142 from Yr10, Yr15, Yr24 , and Yr26 , suggesting that these 2 SSR markers may be used as diagnostic ones for the gene in a wheat breeding program against stripe rust. Based on these findings, YrC142 is most likely a new gene or a new allele at the Yr26 locus, which provides an opportunity to diversify stripe rust-resistant resources for wheat breeding programs.
Summary
Harmaline and harmine accounted for more than 70% in composition in extracts of P. harmala. More attention, however, should be paid to the other alkaloids which would be favorable or unfavorable to the efficacy and safety of the products. It was necessary to determine these trace alkaloids in the extracts; thereafter, most of them have been characterized. Diglycoside vasicine, vasicine, vasicinone, harmalol, harmol, tetrahydroharmine, 8-hydroxy-harmine, ruine, harmaline, and harmine were separated and identified with reference substances and characteristic MS spectra in extracts by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Three trace alkaloids, vasicine, harmalol, and harmol were determined using the developed chromatographic separation method subsequently. The average contents of vasicine, harmalol, and harmol in extracts of ten batches were 2.53 ± 0.73, 0.54 ± 0.19, and 0.077 ± 0.03%, respectively. The total content of the three alkaloids was 3.23 ± 0.90% (from 1.81 to 4.48%). For rough estimation of all the relative alkaloids except of harmaline and harmine, the average total areas of all peaks in extracts varied from 4.35 to 26.64% detected at 220, 254, 265, 280, and 380 nm, respectively. The results indicated that area normalization method was powerless for the quality evaluation for traditional herb medicine consisting of numerous compounds with highly differential features. It might be concluded that LC-MS or HPLC could be utilized as a qualitative and quantitative analytical method for quality control of the extracts from seeds of P. harmala L.
