1.Purely Chemical Approach for Preparation of d-α-Amino Acids via (S)-to-(R)-Interconversion of Unprotected Tailor-Made α-Amino Acids.
Nian Y1, Wang J1, Zhou S1, Dai W1, Wang S1, Moriwaki H2, Kawashima A2, Soloshonok VA3, Liu H1. J Org Chem. 2016 Apr 18. [Epub ahead of print]
Unnatural (R)-α-amino acids (α-AAs) are in growing demand in the biomedical research and pharmaceutical industries. In this work, we present development of a purely chemical approach for preparation of (R)-α-AAs via (S)-to-(R)-interconversion of natural and tailor-made (S)-α-AAs. The method can be used on free, unprotected α-AAs and features a remarkable structural generality including substrates bearing tertiary alkyl chains and reactive functional groups. These attractive characteristics, combined with simplicity of reaction conditions and virtually complete stereochemical outcome, constitute a true methodological advance in this area, rivaling previously reported chemical and biocatalytic approaches.
2.A comparison of natural (D-α-tocopherol) and synthetic (DL-α-tocopherol acetate) vitamin E supplementation on the growth performance, meat quality and oxidative status of broilers.
Cheng K1, Niu Y1, Zheng X1, Zhang H1, Chen Y1, Zhou Y1, Zhang L1, Wang T1. Asian-Australas J Anim Sci. 2016 Jan 18. doi: 10.5713/ajas.15.0819. [Epub ahead of print]
The present study was conducted to compare the supplementation of natural (D-α-tocopherol) and synthetic (DL-α-tocopherol acetate) vitamin E on the growth performance, meat quality, muscular antioxidant capacity and genes expression related to oxidative status of broilers. A total of 144 1 day-old Arbor Acres broiler chicks were randomly allocated into 3 groups with 6 replicates of 8 birds each. Birds were given a basal diet (control group), and basal diet supplemented with either 20 IU D-α-tocopherol or DL-α-tocopherol acetate for 42 days, respectively. The results indicated that treatments did not alter growth performance of broilers (p>0.05). Compared with the control group, concentration of α-tocopherol in the breast muscle was increased by the supplementation of vitamin E (p<0.05). In the thigh, α-tocopherol content was also enhanced by vitamin E inclusion, and this effect was more pronounced in the natural vitamin E group (p<0.
3.Active Tumor Permeation and Uptake of Surface Charge-Switchable Theranostic Nanoparticles for Imaging-Guided Photothermal/Chemo Combinatorial Therapy.
Hung CC1, Huang WC1, Lin YW1, Yu TW1, Chen HH2, Lin SC2, Chiang WH1, Chiu HC1. Theranostics. 2016 Jan 1;6(3):302-17. doi: 10.7150/thno.13686. eCollection 2016.
To significantly promote tumor uptake and penetration of therapeutics, a nanovehicle system comprising poly(lactic-co-glycolic acid) (PLGA) as the hydrophobic cores coated with pH-responsive N-acetyl histidine modified D-α-tocopheryl polyethylene glycol succinate (NAcHis-TPGS) is developed in this work. The nanocarriers with switchable surface charges in response to tumor extracellular acidity (pHe) were capable of selectively co-delivering indocyanine green (ICG), a photothermal agent, and doxorubicin (DOX), a chemotherapy drug, to tumor sites. The in vitro cellular uptake of ICG/DOX-loaded nanoparticles by cancer cells and macrophages was significantly promoted in weak acidic environments due to the increased protonation of the NAcHis moieties. The results of in vivo and ex vivo biodistribution studies demonstrated that upon intravenous injection the theranostic nanoparticles were substantially accumulated in TRAMP-C1 solid tumor of tumor-bearing mice.
4.Transferrin liposomes of docetaxel for brain-targeted cancer applications: formulation and brain theranostics.
Sonali1, Singh RP1, Singh N2, Sharma G3, Vijayakumar MR4, Koch B3, Singh S4, Singh U5, Dash D2, Pandey BL1, Muthu MS1,4. Drug Deliv. 2016 Mar 31:1-11. [Epub ahead of print]
Diagnosis and therapy of brain cancer was often limited due to low permeability of delivery materials across the blood-brain barrier (BBB) and their poor penetration into the brain tissue. This study explored the possibility of utilizing theranostic d-alpha-tocopheryl polyethylene glycol 1000 succinate mono-ester (TPGS) liposomes as nanocarriers for minimally invasive brain-targeted imaging and therapy (brain theranostics). The aim of this work was to formulate transferrin conjugated TPGS coated theranostic liposomes, which contain both docetaxel and quantum dots (QDs) for imaging and therapy of brain cancer. The theranostic liposomes with and without transferrin decoration were prepared and characterized for their particle size, polydispersity, morphology, drug encapsulation efficiency, in-vitro release study and brain theranostics. The particle sizes of the non-targeted and targeted theranostic liposomes were found below 200 nm. Nearly, 71% of drug encapsulation efficiency was achieved with liposomes.