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795.
Hong IS  Suh J 《Organic letters》2000,2(3):377-380
[structure: see text] Transesterification of 2-hydroxypropyl-p-nitrophenyl phosphate in the presence of 0.092 M HClO4 is 50-5000 times faster in acetonitrile, 1,4-dioxane, methanol, ethanol, N,N-dimethylformamide, or dimethyl sulfoxide than in water. This demonstrates the importance of tuning the microenvironments in designing synthetic nucleases.  相似文献   
796.
Diabetes mellitus (DM) is a chronic metabolic disorder characterized by inappropriate hyperglycemia, which causes endothelial dysfunction and peripheral neuropathy, ultimately leading to multiple complications. One prevalent complication is diabetic erectile dysfunction (ED), which is more severe and more resistant to treatment than nondiabetic ED. The serum glycoprotein leucine-rich ɑ-2-glycoprotein 1 (LRG1) is a modulator of TGF-β-mediated angiogenesis and has been proposed as a biomarker for a variety of diseases, including DM. Here, we found that the adhesion GPCR latrophilin-2 (LPHN2) is a TGF-β-independent receptor of LRG1. By interacting with LPHN2, LRG1 promotes both angiogenic and neurotrophic processes in mouse tissue explants under hyperglycemic conditions. Preclinical studies in a diabetic ED mouse model showed that LRG1 administration into the penile tissue, which exhibits significantly increased LPHN2 expression, fully restores erectile function by rescuing vascular and neurological abnormalities. Further investigations revealed that PI3K, AKT, and NF-κB p65 constitute the key intracellular signaling pathway of the LRG1/LPHN2 axis, providing important mechanistic insights into LRG1-mediated angiogenesis and nerve regeneration in DM. Our findings suggest that LRG1 can be a potential new therapeutic option for treating aberrant peripheral blood vessels and neuropathy associated with diabetic complications, such as diabetic ED.Subject terms: Biological therapy, Cytokines, Recombinant protein therapy, Extracellular signalling molecules  相似文献   
797.
We describe a robust method for both encapsulating and stabilizing photo‐sensitive antioxidants in polymer microcapsules prepared by a water‐in‐oil‐in‐water double emulsification and evaporation technique, in which a volatile solvent from the oil layer consisting of poly(methyl methacrylate) and methylene chloride is gradually removed. Using poly(ethylene glycol) (PEG) in this study, we demonstrate that control over its molecular weight allows to tune the phase property of the capsule wall; introducing PEG with high molecular weight results in increased heterogeneity. The heterogeneity of the capsule walls displays an ability to effectively block sunlight, which is essential for improving the molecular stability of photo‐sensitive antioxidants. In this study, we experimentally confirm this by observing natural sunlight‐driven molecular decomposition of a model antioxidant, riboflavin‐5′‐phosphate, in poly (methyl methacrylate) microcapsules.

  相似文献   

798.
In this paper, first we introduce the full expression for the Ricci tensor of a real hypersurface MM in complex two-plane Grassmannians G2(Cm+2)G2(Cm+2) from the equation of Gauss. Next we prove that a Hopf hypersurface in complex two-plane Grassmannians G2(Cm+2)G2(Cm+2) with commuting Ricci tensor is locally congruent to a tube of radius rr over a totally geodesic G2(Cm+1)G2(Cm+1). Finally it can be verified that there do not exist any Hopf Einstein hypersurfaces in G2(Cm+2)G2(Cm+2).  相似文献   
799.
The mono(dpa)copper(II) complex [Cu(dpa)Cl2] (1) (dpa = di-(2-picolyl)amine) has been synthesized and structurally characterized. It crystallizes in the monoclinic system P21/n with a = 8.155(1), b = 12.560(1), c = 12.817(2) Å, = 91.64(2)°, V = 1312.3(2) Å3, Z = 4. The copper atom is coordinated by three nitrogen atoms from the dpa ligand and two chlorides in a distorted square-pyramidal environment. Cyclic voltammetric data show that 1 undergoes the reversible one-electron oxidation to the Cu(III) and the reversible one-electron reduction to the Cu(I) state.  相似文献   
800.
Suh HH 《Optics letters》1999,24(10):661-663
A novel, simple scheme for producing full-color images by use of binary-phase holograms and red (632.8-nm), green (543.5-nm), and blue (488-nm), lasers is reported. The theory and experimental results of the system are also presented.  相似文献   
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