Construction of the Subtracted cDNA Library of Striatal Neurons Treated with Long-term Morphine

Objective To construct a morphine tolerance model in primarily cultured striatal neurons, and screen the differentially expressed genes in this model using suppression subtractive hybridization （SSH）. Methods Sbtracted cDNA libraries were constructed using SSH from normal primarily cultured striatal neurons and long-term morphine treated striatal neurons （10^-5 mol/L for 72 hours）. To check reliability of the cell culture model, RT-PCR was performed to detect the cAMP-responsive element-binding protein （CREB） mRNA expression. The subtracted clones were prescreened by PCR. The clones containing inserted fragments from forward libraries were sequenced and submitted to GenBank for homology analysis. And the expression levels of genes of interest were confirmed by RT-PCR. Results CREB mRNA expression showed a significant increase in morphine treated striatal neurons （62.85± 1.98） compared with normal striatal neurons （28.43 ± 1.46, P〈0.01）. Thirty-six clones containing inserted fragments were randomly chosen for sequence analysis. And the 36 clones showed homology with 19 known genes and 2 novel genes. The expression of 2 novel genes, mitochondrial carrier homolog 1 （Mtchl ; 96.81±2.04 vs. 44.20±1.31, P〈0.01） and thyrnoma viral proto-oncogene 1 （Akt1 ; 122.10±2.17 vs 50.11±2.01, P〈0.01）, showed a significant increase in morphine-treated striatal neurons compared with normal striatal neurons. Conclusions A reliable differential cDNA library of striatal neurons treated with long-term morphine is constructed. Mtchl and Aktl might be the candidate genes for the development of morphine tolerance.

Polydopamine modified CuS@HKUST for rapid sterilization through enhanced photothermal property and photocatalytic ability

Because of the impressive evolution of the drugresistant bacteria,the development of efficient,antibioticfree agent is in great urgency.Herein,an efficient antibacterial agent,CuS@HKUST-polydopamine(PDA),was exquisitely designed,where the Cu-based metal-organic framework(MOF)—HKUST nanoparticles served as the porous frame,and the CuS was synthesized within the structure of the MOF through the process of in situ sulfuration,followed with polydopamine(PDA)covering the nanoparticles.The structure of the HKUST preventing the aggregation of the CuS nanoparticles,which improved their photothermal and photocatalytic properties.After covering with PDA,the nanoparticles’abilities to produce heat and free radicals were further enhanced.This was because that the PDA itself could transform light into heat,which not only benefited the photothermal property,but also improved the photocatalytic property of the nanoparticles by accelerating the charge mobility.Moreover,the PDA could also transfer the photo-induced electrons fast and thus prevented the recombination of the photo-generated electron–hole pairs,which resulted in the enhanced ability to produce free radicals.As a result,under light irradiation,the antibacterial efficiency of the CuS@HKUST-PDA against Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)could reach 99.77%and 99.57%.Hence,the synthesized CuS@HKUST-PDA can be promising for anti-infection and sterilization application without using antibiotics.