Tumour necrosis factor‐related apoptosis‐inducing ligand (TRAIL) has attracted much attention because of its ability to kill tumour cells. In this study, we demonstrated that treatment of QGY‐7703 cells with the combination of TRAIL and etoposide resulted in synergistic cytotoxic effects. In dissecting the mechanism underlying this synergistic effect, we found that treatment with etoposide alone resulted in the upregulation of Bax, while the level of truncated Bid (tBid) was unchanged. In contrast, while treatment with TRAIL alone significantly increased the level of tBid, the expression of Bax remained unaffected. The enhanced apoptosis was accompanied by an increased release of cytochrome c and second mitochondria‐derived activator of caspase/direct IAP binding protein with low pI (DIABLO) from mitochondria, leading to the activation of cellular caspase‐8, ‐9, ‐3 and ‐7, as well as poly ADP‐ribose polymerase. This enhanced release of cytochrome c and second mitochondria‐derived activator of caspase/DIABLO was inhibited by the general caspase inhibitor N ‐benzyloxycarbonyl‐Val‐Ala‐Asp‐fluoromethylketone. The RT–PCR and Western blotting results demonstrated that the levels of both mRNA and protein for death receptor‐4, death receptor‐5 and decoy receptor‐2 remained unchanged in response to etoposide, indicating that the synergistic effect of TRAIL and etoposide is not a result of increasing the expression for TRAIL receptors, but rather is associated with amplification of the mitochondrial signal pathway.
A reverse transcription loop-mediated isothermal amplification(RT-LAMP) assay was developed for detection of H9 subtype avian influenza virus(AIV).According to the sequences of H9 subtype AIV hemagglutinin gene available in GenBank,six primers specific to the eight site of HA gene were designed,and the reaction conditions were optimized.The results showed that the assay had no cross-reaction with H3,H5,H7 subtype AIV and other avian respiratory pathogens.The assay was performed in water bath within 50 minutes and the amplification result was visualized by adding SYBR GREENⅠor inspecting the white sediment.The detection limit of RT-LAMP assay was 0.01pg,which was 103-fold higher than that of one-step RT-PCR.These results suggested that the newly developed RT-LAMP assay is a simple and specific method for rapid detection of H9 subtype AIV in field conditions.
Rational design and engineering of high-efficiency electrocatalysts toward overall water splitting is crucial for the development of hydrogen energy technology. Herein, a facile procedure is described for the preparation of effective bifunctional electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), where ruthenium nanoparticles are supported on graphene nanosheets that are codoped with atomic cobalt and nitrogen by controlled pyrolysis of melamine-functionalized graphene oxide and metal ion precursors. The obtained nanocomposites (CoNG/Ru) exhibit a remarkable electrocatalytic activity toward both HER and OER in alkaline media, with a respective overpotential of only -15 and +350 mV to reach the current density of 10 mA cm-2, which is much better than the monometallic counterparts and relevant catalysts in the literature. With CoNG/Ru as bifunctional catalysts for overall water splitting in a two-electrode system, a low potential of 1.58 V is needed to reach the current density of 10 mA cm-2, which is even better than that with commercial Pt/C and RuO2 catalysts. This is ascribed to the synergistic interactions between the metal species by metal-metal charge transfer. These results highlight the significance of exploiting the electronic interactions between metal species in carbon-based nanocomposites to develop bifunctional catalysts for electrochemical energy technologies.
We report a facile method of synthesizing grain-boundary(GB)-rich platinum nanoparticle assembly. GBs are formed between platinum nanoparticles during their random collision and attachment in solution driven by water electrolysis. The GB-rich nanoparticle assembly exhibits ~400-fold higher catalytic hydrogen oxidation rate than platinum nanoparticles before assembly, enabling catalytic hydrogen sensing at room temperature without external heating. Our sensor also demonstrates fast response/recovery (~7 s at >1% H2), nearly no signal variation during a 280-hour-long stability test, and high selectivity toward hydrogen over 36 interference gases. Furthermore, this sensor can be easily fabricated from commercial thermometers at a low cost (< $5 per unit). Theoretical calculation results reveal that the high performance of GB-rich platinum nanoparticle assembly arises from tensile strain at the GBs.
With the incorporation of ruthenium metal ions into the molecular skeleton by Ru–N coordination bonds, carbon nitride nanosheets exhibit apparent electrocatalytic activity towards hydrogen evolution reaction.
The aim of this study was to analyze the combination of three kinds of in-house IFN-γ ELISPOT using peptide A53 and peptide mixtures (E6 + E7 and E6 + E7 + C14) with tuberculin skin test (TST) to detect latent TB infection (LTBI) in China. A total of 788 healthy people were recruited and analyzed by three kinds of IFN-g ELISPOT, 581 of them had TST results, of which 147 samples were also compared with the T- SPOT.TB test. The positive detection rates for T- SPOT.TB and three kinds of IFN-γ ELISPOT with A53, E6 + E7 and E6 + E7 + C14 were 14.28% (21/147), 29.43% (171/581), 23.24% (135/581) and 28.40% (165/581), respectively. These results were significantly lower than the positive TST results, which were positive in 82.99% (122/147) and 75.73% (440/ 581), respectively. The positive detection rates of three kinds of IFN-γ ELISPOT (31.60%, 26.65% and 32.11% in 788 cases, respectively) could better reflect over 40.00% of Mycobacterium tuberculosis (MTB) infection rate in China. Detection rates between contacts and non-contacts by three kinds of IFN-γ ELIS-POT were not significantly different (p > 0.05). It can be seen that the three kinds of in-house IFN-γ ELIS- POT might be used as a complementary tool of T- SPOT.TB for detecting LTBI in the healthy population of China.
Since 2000, more and more NS fragment of H5N1 subtype influenza A virus had a unique deletion of nuleotides from 263 to 277. In order to investigate the biological significance of the mutation, four recombinants, RWSN-848, RWSN-m848, RWSN-248 and RWSN-m248, were generated via eight-plasmid reverse genetic system. These reassortants had the same inner gene and outer gene derived from A/WSN/33(H1N1) and A/D/SD/04(H5N1), respectively. But their NS genes were different. RWSN-m248 and RWSN-848 were isogenic with RWSN-248 and RWSN-m848 respectively, except for the NS gene, the formers encoded a mutant NS with a deletion from 263 - 277 nucleotides. All of the four recombinants could grow well in embryonated chicken eggs and had the similar viral titer, EID50 and MDT. Infections were done with the same Multiplicity of infection (MOI, 0.001), and the viruses in supernatants from infected cells were titrated at 12, 24, 36, and 48 h post-infection by plaque assay in fresh MDCK. The results show that four viruses grown well and had the same viral title in Vero cell, a non-IFN-responsive cell system. But in MDCK and COS-1, the cell lines can produce IFN, RWSN-248 and RWSN-m848 had a higher viral titer (two fold) than RWSN-m248 and RWSN-848. It revealed that the deletion of nucleotides of NS from 263 - 277 of H5N1 influences decreases viral growth ability in IFN producing cell line. IVPI were done for the virulence test of reassorted H5N1 viruses. Ten six-week-old SPF White Leghorn chickens were inoculated intravenously with 0.2mL of a 1:10 dilution of allantoic fluid containing each of the four recombinant viruses. The chickens were daily monitored for disease signs and death for 10 days post-inoculation. Finally, IVPI was counted for each virus. RWSN-m248 caused 4 chickens died in 10 days and its index was 1.63. RWSN-248 only caused one chicken died and its index was 0.45. RWSN848 caused 3 chickens died in 10 days and its index was 0.81. RWSN-m848 caused one of the ten chickens died and its' index was only 0.175. The results revealed that the deletion of nucleotides of NS gene from 263 to 277 sites increases H5N1 pathogenesis in chicken.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)