| 1 | Vasorelaxant effect of osthole on isolated thoracic aortic rings in rats显示文摘OBJECTIVE: To investigate the effect of osthole on isolated thoracic aortic rings, and to determine the potential mechanism of action.METHODS: Thoracic aortas were isolated from Wistar rats, and were suspended in tissue organ chambers for vascular tension measurement. The effect of cumulative osthole(10-9, 10-8, 10-7, 10-6, and 10-5 mol/L) on endothelium-intact and endothelium-denuded thoracic aortic rings pre-contracted with phenylephrine(PE, 10-6 mol/L) or KCl(6 × 10-2 mol/L) was recorded. Histomorphological changes of thoracic aorta were analyzed by hematoxylin-eosin. The effects of different osthole concentrations on endothelium-intact aortic rings, which were pre-inhibited with the non-selective nitric oxide synthase inhibitor L-Arg(NO2)-OMe·HCl(3 × 10-4 mol/L), endothelium-derived nitric oxide synthase inhibitor Nω-nitro-L-arginine(3 × 10-4 mol/L), guanylate cyclase inhibitor 1 H-[1,2,4] oxadiazolo [4,3-α]quinoxaline-1-one(10-5 mol/L), cyclooxygenase inhibitor indometacin(10-5 mol/L), and the Ca2+-activated potassium channel inhibitor tetraethylammonium nitrate(10-5 mol/L), and then contracted with PE, were examined. Aortic rings incubated with osthole(10-5 mol/L), phentolamine(10-5 mol/L), or verapamil(10-5 mol/L) in Ca2+-free Krebs-Henseleit solution(KHS) were stimulated with PE or KCl.RESULTS: There was a dose-dependent increase in vasorelaxation of isolated thoracic aortic rings(both with and without endothelium) with increasing osthole concentration. Hematoxylin-eosin staining showed that osthole significantly improved thoracic aorta ring morphology. Compared with the control group, there were also significant differences after incubation with L-Arg(NO2)-OMe ω-nitro-L-arginine, and 1 H-[1,2,4] oxadiazo·lo HCl,N [4,3-α] quinoxaline-1-one(P < 0.05 for all). The relaxation rate of the rings in the osthole group incubated with indometacin and tetraethylammonium nitrate were similar to controls. In Ca2+-free KHS, the PE-induced contraction was similar between the osthole(4.37% ± 0.41%) and control(4.21% ± 1.33%)groups. However, after cumulative CaCl2(0.5, 1, 1.5,2, 2.5, and 3 mmol/L), the Ca2+-induced contraction was significantly inhibited in the osthole and phentolamine groups compared with controls(P < 0.05).After cumulative CaCl2 was added to Ca2+-free KHS(high K+ concentration), the contraction rate was significantly higher than both of the control and the osthole groups(P < 0.05). The contraction rate in the osthole group was higher than the verapamil group(P < 0.05).CONCLUSION: Osthole has a vasorelaxant effect on isolated rat thoracic aortic rings, via inhibition of both receptor-operated and voltage-dependent Ca2+channels in arterial smooth muscle, leading to decreased Ca2+ influx, and via inhibition of nitric oxide release on arterial endothelial cells. | Huang Ying Kong Liting Wang Yanping Sun Mingjie Cui Haifeng Zhai Huaqiang LüCheng Fan Danping | 2019 | Journal of Traditional Chinese Medicine2019，39，4： | 1 |
| 2 | Enzymatic cascade systems for D-amino acid synthesis:progress and perspectives显示文摘D-amino acids,different from the ubiquitous L-amino acids,are recognized as the“unnatural”amino acids.The applications of D-amino acids have drawn increasing interest from researchers in recent years,and D-amino acids are widely used in various industries,including for food products,pharmaceuticals,and agricultural chemicals.Inspired by the prevalent appli-cations,many synthetic methods for D-amino acids have been developed,which are mainly divided into chemical synthetic methods and biosynthetic methods.Chemical synthesis of D-amino acids has a variety of disadvantages such as multiple reaction steps,low yields,low reaction rates,and difficulties in product extraction.Thus,biosynthetic methods utilizing enzymes are attracting increasing attention because they are more energy-saving and environmentally friendly compared to traditional chemical synthesis.Among all enzymatic methods,multi-enzymatic cascade catalytic methods have significant advantages,such as lower costs,no need for intermediate separation,and higher catalytic efficiency,which is ascribed to the spatial proximity of biocatalysts.In this review,advances in multi-enzyme cascade catalytic systems as well as chemo-enzymatic approaches to synthesize D-amino acids are discussed. | Anwen Fan Jiarui Li Yangqing Yu Danping Zhang Yao Nie Yan Xu | 2021 | Systems Microbiology and Biomanufacturing2021，1，4： | 1 |
| 3 | Characteristics of diffusion-tensor imaging for healthy adult rhesus monkey brains显示文摘Diffusion-tensor imaging can be used to observe the microstructure of brain tissue.Fractional anisotropy reflects the integrity of white matter fibers.Fractional anisotropy of a young adult brain is low in gray matter,high in white matter,and highest in the splenium of the corpus callosum.Thus,we selected the anterior and posterior limbs of the internal capsule,head of the caudate nucleus,semioval center,thalamus,and corpus callosum(splenium and genu)as regions of interest when using diffusion-tensor imaging to observe fractional anisotropy of major white matter fiber tracts and the deep gray matter of healthy rhesus monkeys aged 4–8 years.Results showed no laterality differences in fractional anisotropy values.Fractional anisotropy values were low in the head of caudate nucleus and thalamus in gray matter.Fractional anisotropy values were highest in the splenium of corpus callosum in the white matter,followed by genu of the corpus callosum and the posterior limb of the internal capsule.Fractional anisotropy values were lowest in the semioval center and posterior limb of internal capsule.These results suggest that fractional anisotropy values in major white matter fibers and the deep gray matter of 4–8-year-old rhesus monkeys are similar to those of healthy young people. | Xinxiang Zhao Jun Pu Yaodong Fan Xiaoqun Niu Danping Yu Yanglin Zhang | 2013 | Neural Regeneration Research2013，8，31： | 0 |
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