[Effect of polydatin on the proliferation and apoptosis of THP-1 cells and the mechanism]. / 虎杖苷对THP-1ç»†èƒžå¢žæ®–åŠå‡‹äº¡çš„å½±å“åŠå ¶ä½œç”¨æœºåˆ¶ç ”ç©¶.

OBJECTIVES: To explore the effect of polydatin on the proliferation and apoptosis of acute monocytic leukemia cell line THP-1 and the possible mechanism. METHODS: After THP-1 cells were treated with polydatin at gradient concentrations for 24 hours and 48 hours, their proliferation was determined by CCK-8 assay, and half maximal inhibitory concentration (IC50) was calculated. Logarithmically growing THP-1 cells were divided into two groups, a polydatin treatment group (treated with IC50 of polydatin) and a blank control group (treated without polydatin solution), and incubated for 48 hours. Cell apoptosis and cell cycle were measured by flow cytometry. The expression levels of PI3K, AKT, p-AKT, mTOR, p-mTOR, p70 S6K, and p-p70 S6K proteins were measured by Western blotting. RESULTS: After treatment with polydatin, the proliferation of THP-1 cells was strongly inhibited, and the IC50 at 48 hours was 1 800 µmol/L. After treatment with 1 800 µmol/L polydatin solution for 48 hours, the apoptosis rate of THP-1 cells increased significantly compared with the blank control group (P<0.05). The cell cycle was arrested in the G0/G1 and S phases, with a significantly increased proportion of cells in the G0/G1 phase and a significantly decreased proportion of cells in the S phase, as compared with the blank control group (P<0.05). The expression levels of PI3K, AKT, p-AKT, mTOR, p-mTOR, p70 S6K, and p-p70 S6K proteins decreased significantly compared with the blank control group (P<0.05). CONCLUSIONS: Polydatin can effectively inhibit the proliferation, block the cell cycle, and induce the apoptosis of THP-1 cells, which may be related to inhibition of the PI3K/AKT/mTOR signaling pathway.

Dog vaccination with EgM proteins against Echinococcus granulosus.

BACKGROUND: Dogs play a pivotal role in the transmission of cystic echinococcosis (CE), a zoonosis caused by the tapeworm Echinococcus granulosus. We showed previously that dogs vaccinated with two E. granulosus adult-worm specific proteins, EgM9 and EgM123, emulsified with Freund's adjuvants induced significant protective efficacy in terms of reduction in worm burden and egg production after 45 days post-infection. It was not known whether this protection can be sustained using adjuvants suitable for use in dogs. METHODS: Recombinant EgM9 and EgM123 were mixed with Quil A or ISCOMs for vaccinating dogs. After three vaccine injections, all the dogs were orally challenge-infected with 200 000 protoscoleces of E. granulosus. After 45 days of infection, all the dogs were euthanized and necropsied for collecting and counting E. granulosus worms. Immunoglobins, including the IgG subclasses IgG1 and IgG2, were detected in the sera of vaccinated dogs by ELISA. To determine whether the protection efficacy could be maintained after 45 days post-infection, we implemented a longevity trial to count eggs in dog faeces for 170 days after infection. RESULTS: The dogs vaccinated with EgM9 and EgM123 mixed with Quil A and ISCOMs showed similar protective efficacy as the proteins emulsified with Freund's adjuvants in our previous study in terms of reduction of worms and eggs at 45 days post-infection. The longevity trial showed that EgM9 protein-vaccinated group released lower number of eggs per gram compared with the egg counts in the control dogs during the dog trial study. CONCLUSION: EgM9 and EgM123 are thus suitable vaccine candidates against E. granulosus infection in dogs.

Cuprous oxide nanospheres as probes for light scattering imaging analysis of live cells and for conformation identification of proteins.

A facile solution-phase synthesis route of highly uniform Cu(2)O nanospheres (Cu(2)O NPs) with the size of 57.7+/-4.7nm was developed, and then the nanoparticles were applied to live cell imaging under a common dark-field microscope. Starting from copper(II) salts, the synthesis of Cu(2)O NPs was made in the presence of cetyltrimethylammonium bromide (CTAB) by reducing the copper(II) with sodium borohydride (NaBH(4)) in aqueous medium and by aging process in the air. Monitoring of morphology evolution process of Cu(2)O NPs with scanning electron microscopy (SEM) and measuring of the UV-visible spectra showed that the synthesis of Cu(2)O NPs follows the reduction-oxidation coupled process of Cu(2+) into Cu(0) species at first and then the resulted Cu(0) species into Cu(2)O NPs in the air. Light scattering (LS) features have been measured with a common spectrofluorometer and a common dark-field microscope, and it was found that the as-prepared Cu(2)O NPs display strong blue scattering light and can be applied for cell imaging. If incubated with human bone marrow neuroblastoma, transferrin-conjugated Cu(2)O NPs can get into the cells and show strong pure blue light in cytoplasm. Further investigations showed that the Cu(2)O NPs could be applied for probes for conformation of proteins.

Visual and light scattering spectrometric detections of melamine with polythymine-stabilized gold nanoparticles through specific triple hydrogen-bonding recognition.

Melamine can be sensitively detected in aqueous medium through its selective interaction with polythymine (polyT(n)) modified gold nanoparticles (AuNPs) by forming triple H-bonds, which results in aggregation of the polyT(n)-stabilized AuNPs, displaying variations of localized plasmon resonance features such as colour change from red to purple and enhanced localized surface plasmon resonance light scattering (LSPR-LS) signals.