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A facile approach to the synthesis of some side-chain-protected amino acids via oxalic acid dihydrate as the copper sequestering reagent is presented. The copper in the amino acid complex reacted with oxalic acid dihydrate to form insoluble cupric oxalate, with the free amino acid released. Compared with conventional methods, this method is convenient, inexpensive, and environmentally friendly. Key words: side-chain-protected amino acid, oxalic acid dihydrate, cupric oxalate, synthesis. On a mis au point une approche simple a la synthese des divers acides amines a chafne laterale protegee impliquant le dihydrate de l'acide oxalique comme reactif de sequestration de du cuivre. Le cuivre du complexe avec l'acide amine reagit avec le dihydrate de l'acide oxalique pour former l'oxalate cuivrique insoluble et la liberation de l'acide amine libre. Par comparaison avec les autres methodes conventionnelles, cette methode est pratique, peu couteuse et ecologique. Mots-cles: acide amine a chafne laterale protegee, dihydrate de l'acide oxalique, oxalate cuivrique, synthese., Introduction Since the emergence of glycylglycine synthesis from a diketopiperazine by Fischer and Fourneau1 in 1901, peptide synthesis has undergone tremendous progress and it is now possible to routinely synthesize [...]

Aim: Brain-derived neurotrophic factor (BDNF) could promote the survival and differentiation of neural cells in peripheral and central nervous systems during development. Emerging evidences identified BDNF as an oncoprotein which could promotes progression and prognosis of tumors such as giloma, lung cancer and gastric cancer. We performed experiments to investigate the expression and clinical significance of BDNF in intrahepatic cholangiocarcinoma (IHCC)., Materials and Methods: The expression of BDNF and vascular endothelial growth factor (VEGF) was detected with immunohistochemistry in 96 patients with cholangiocarcinoma. The correlations between BDNF and the clinicopathologic factors were evaluated with Fisher test. The prognostic values of BDNF and VEGF were analyzed by the univariate analysis with Kaplan-Meier test and independent prognostic factor was identified by multivariate analysis with Cox-regression model. The effect of endogenous and exogenous BDNF on the invasion of IHCC cell line RBE was explored by transwell assay., Results: The percentage of high expression of BDNF was 35.96% (34/96). High expression of BDNF was significantly associated with positive intraneural invasion (P=0.012) and low overall survival rate (P=0.006). High expression of BDNF was identified as an independent prognostic factor in IHCC (P=0.032). With Matrigel transwell assay, we demonstrated that both endogenous and exogenous BDNF could promote the invasion of IHCC cells., Conclusions: High expression BDNF was identified as an independent risk in IHCC indicating poorer prognosis. Both endogenous and exogenous BDNF could promote the invasion of IHCC cells, indicating that BNDF may promote IHCC invasion in a paracrine or autocrine pathway., Competing Interests: None., (IJCEP Copyright © 2017.)