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31.
32.
I-Ching Sam Yvonne C. F. Su Yoke Fun Chan Siti Sarah Nor'E Ardalinah Hassan Faizatul Lela Jafar Udayan Joseph Rebecca A. Halpin Elodie Ghedin Poh Sim Hooi Mathieu Fourment Hamimah Hassan Sazaly AbuBakar David E. Wentworth Gavin J. D. Smith 《Journal of virology》2015,89(18):9689-9692
Influenza B virus causes significant disease but remains understudied in tropical regions. We sequenced 72 influenza B viruses collected in Kuala Lumpur, Malaysia, from 1995 to 2008. The predominant circulating lineage (Victoria or Yamagata) changed every 1 to 3 years, and these shifts were associated with increased incidence of influenza B. We also found poor lineage matches with recommended influenza virus vaccine strains. While most influenza B virus lineages in Malaysia were short-lived, one circulated for 3 to 4 years. 相似文献
33.
Fifteen novel six-membered azanucleoside derivatives were prepared and evaluated for their anti-hepatitis B virus (HBV) activity and cytotoxicity in human hepatoblastoma-derived liver Hep-G2 cells. The most potent compound 16b with an IC(50) value of 2.74μg/mL (lower than 3TC) and a SI value of 13.5 was disclosed. The key synthetic steps involved the rearrangement of lactones (which were readily obtained from monosaccharides) and the Lewis acid-catalyzed condensation of nucleobases with azasugar donors. Using the versatile acetylated azasugar donors, azanucleosides covering three types of azasugars and four types of natural nucleobases were successfully obtained. The experimental results showed that some six-membered azanucleosides may find applications in the discovery of new anti-viral agents. 相似文献
34.
Hsing CH Lin MC Choi PC Huang WC Kai JI Tsai CC Cheng YL Hsieh CY Wang CY Chang YP Chen YH Chen CL Lin CF 《PloS one》2011,6(3):e17598
Background
Anesthetic propofol has immunomodulatory effects, particularly in the area of anti-inflammation. Bacterial endotoxin lipopolysaccharide (LPS) induces inflammation through toll-like receptor (TLR) 4 signaling. We investigated the molecular actions of propofol against LPS/TLR4-induced inflammatory activation in murine RAW264.7 macrophages.Methodology/Principal Findings
Non-cytotoxic levels of propofol reduced LPS-induced inducible nitric oxide synthase (iNOS) and NO as determined by western blotting and the Griess reaction, respectively. Propofol also reduced the production of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-10 as detected by enzyme-linked immunosorbent assays. Western blot analysis showed propofol inhibited LPS-induced activation and phosphorylation of IKKβ (Ser180) and nuclear factor (NF)-κB (Ser536); the subsequent nuclear translocation of NF-κB p65 was also reduced. Additionally, propofol inhibited LPS-induced Akt activation and phosphorylation (Ser473) partly by reducing reactive oxygen species (ROS) generation; inter-regulation that ROS regulated Akt followed by NF-κB activation was found to be crucial for LPS-induced inflammatory responses in macrophages. An in vivo study using C57BL/6 mice also demonstrated the anti-inflammatory properties against LPS in peritoneal macrophages.Conclusions/Significance
These results suggest that propofol reduces LPS-induced inflammatory responses in macrophages by inhibiting the interconnected ROS/Akt/IKKβ/NF-κB signaling pathways. 相似文献35.
Tat‐Ming Lo Hua Ling Susanna Su Jan Leong Chueh Loo Poh Matthew Wook Chang 《Molecular systems biology》2011,7(1)
Synthetic biology aims to systematically design and construct novel biological systems that address energy, environment, and health issues. Herein, we describe the development of a synthetic genetic system, which comprises quorum sensing, killing, and lysing devices, that enables Escherichia coli to sense and kill a pathogenic Pseudomonas aeruginosa strain through the production and release of pyocin. The sensing, killing, and lysing devices were characterized to elucidate their detection, antimicrobial and pyocin release functionalities, which subsequently aided in the construction of the final system and the verification of its designed behavior. We demonstrated that our engineered E. coli sensed and killed planktonic P. aeruginosa, evidenced by 99% reduction in the viable cells. Moreover, we showed that our engineered E. coli inhibited the formation of P. aeruginosa biofilm by close to 90%, leading to much sparser and thinner biofilm matrices. These results suggest that E. coli carrying our synthetic genetic system may provide a novel synthetic biology‐driven antimicrobial strategy that could potentially be applied to fighting P. aeruginosa and other infectious pathogens. 相似文献
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A transformation procedure for phalaenopsis orchid established by using immature protocorms for Agrobacterium infection was aimed at the introduction of target genes into individuals with divergent genetic backgrounds. Protocorms obtained after 21 days of culture on liquid New Dogashima medium were inoculated with Agrobacterium strain EHA101(pIG121Hm) harboring both -glucuronidase (GUS) and hygromycin resistance genes. Subculture of the protocorms on acetosyringone-containing medium 2 days before Agrobacterium inoculation gave the highest transformation efficiencies (1.3–1.9%) based on the frequency of hygromycin-resistant plants produced. Surviving protocorms obtained 2 months after Agrobacterium infection on selection medium containing 20 mg l–1 hygromycin were cut transversely into two pieces before transferring to recovery medium without hygromycin. Protocorm-like bodies (PLBs) proliferated from pieces of protocorms during a 1-month culture on recovery medium followed by transfer to selection medium. Hygromycin-resistant phalaenopsis plants that regenerated after the re-selection culture of PLBs showed histochemical blue staining due to GUS. Transgene integration of the hygromycin-resistant plants was confirmed by Southern blot analysis. A total of 88 transgenic plants, each derived from an independent protocorm, was obtained from ca. 12,500 mature seeds 6 months after infection with Agrobacterium. Due to the convenient protocol for Agrobacterium infection and rapid production of transgenic plants, the present procedure could be utilized to assess expression of transgenes under different genetic backgrounds, and for the molecular breeding of phalaenopsis. 相似文献
38.
Human immunodeficiency virus type 1 Vpr interacts with antiapoptotic mitochondrial protein HAX-1 下载免费PDF全文
Yedavalli VS Shih HM Chiang YP Lu CY Chang LY Chen MY Chuang CY Dayton AI Jeang KT Huang LM 《Journal of virology》2005,79(21):13735-13746
Human immunodeficiency virus type 1 viral protein R (Vpr) is required for viral pathogenesis and has been implicated in T-cell apoptosis through its activation of caspase 3 and caspase 9 and perturbation of mitochondrial membrane potential. To understand better Vpr-mitochondria interaction, we report here the identification of antiapoptotic mitochondrial protein HAX-1 as a novel Vpr target. We show that Vpr and HAX-1 physically associate with each other. Overexpression of Vpr in cells dislocates HAX-1 from its normal residence in mitochondria and creates mitochondrion instability and cell death. Conversely, overexpression of HAX-1 suppressed the proapoptotic activity of Vpr. 相似文献
39.
Synthesis and in vitro antitumor activity of 4(3H)-quinazolinone derivatives with dithiocarbamate side chains 总被引:3,自引:0,他引:3
Cao SL Feng YP Jiang YY Liu SY Ding GY Li RT 《Bioorganic & medicinal chemistry letters》2005,15(7):1915-1917
A series of 4(3H)-quinazolinone derivatives with dithiocarbamate side chains were synthesized and tested for their in vitro antitumor activity against human myelogenous leukemia K562 cells. Among them, (3,4-dihydro-2-methyl-4-oxoquinazolin-6-yl)methyl 4-(4-fluorophenyl)piperazine-1-carbodithioate 8q exhibited significant inhibitory activity against K562 cells with IC(50) value of 0.5 microM. 相似文献
40.