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101.
Severe tick infestation was found in a hare in a suburban area of Nanchang, Jiangxi Province, China. We sampled ticks and identified them based on their morphologic characteristics. Three species, Ixodes sinensis, which is commonly found in China and can experimentally transmit Borrelia burgdorferi, Rhipicephalus haemaphysaloides, and Haemaphysalis longicornis which can transmit Lyme disease were detected with an optical microscope and a stereomicroscope. Risk of spreading ticks from suburban to urban areas exists due to human transportation and travel between the infested and non-infested areas around Nanchang. 相似文献
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Li F He Z Li Y Liu P Chen F Wang M Zhu H Ding X Wangensteen KJ Hu Y Wang X 《Journal of cellular biochemistry》2011,112(4):1022-1034
Induction of definitive endoderm (DE) cells is a prerequisite for the whole process of embryonic stem (ES) cells differentiating into hepatic or pancreatic progenitor cells. We have established an efficient method to induce mouse ES cell-derived DE cells in suspension embryonic body (EB) culture. Similar to previous studies, mouse ES cell-derived DE cells, which were defined as Cxcr4(+) c-Kit(+) , Cxcr4(+) E-cadherin(+) cells or Cxcr4(+) PDGFRa(-) cells, could be induced in the serum-free EBs at Day 4 of induction. The activations of Wnt, Nodal, and FGF signaling pathways in differentiating EBs promoted DE cell differentiation, while activation of BMP4 signaling inhibited the process. In the present study, we found that chemical activation of canonical Wnt signaling pathway by LiCl could synergize with Activin A-mediated Nodal signaling pathway to promote induction of DE cells, and inhibition of Bmp4 signaling by Noggin along with Activin A/LiCl further improved the efficiency of DE cell differentiation. The derived DE cells were proved for their capacities to become hepatic progenitor cells or pancreatic progenitor cells. In conclusion, we significantly improved the efficiency of generating mouse ES cell-derived DE cells by combined Activin A/LiCl/Noggin treatment. Our work will be greatly helpful to generate ES cell-derived hepatic cells and ES cell-derived pancreatic cells for future regenerative medicine. 相似文献
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Lingzhi Zhong Yang Wang Wenxue Li Junlian Gu Xiuying Li Xiaotong Wang Zhen Yue Yan Mu Jinping Bai Ronggui Li Haiying Zhang 《Molecular and cellular biochemistry》2014,392(1-2):135-144
Arsenic trioxide (ATO) has been successfully used to treat leukemia and some solid malignant tumors. Our previous study regarding the effects of ATO on mesenchymal-derived human osteosarcoma MG63 cells showed that heme oxygenase-1 (HO-1) was strongly induced upon treatment with ATO. The present study sought to investigate the effect of silencing HO-1 on the sensitivity of osteosarcoma cells to ATO to determine the potential for therapeutic applications. Small hairpin RNA (shRNA)-mediated interference was used to silence HO-1 in MG63 cells. Viability, apoptosis, and intracellular reactive oxygen species (ROS) of the cells were assessed to evaluate the sensitivity of the cells to ATO as well as the potential mechanisms responsible. shRNA-mediated interference prevented the induction of HO-1, increased cell death, and increased intracellular ROS levels in MG63 cells upon treatment with ATO. Silencing HO-1 increased the susceptibility of MG63 cells to the chemotherapeutic drug ATO by enhancing intracellular accumulation of ROS. Our results suggest that the inhibition of HO-1 could improve the outcome of osteosarcoma treated with ATO. 相似文献
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Jinsheng Liu Caixia Kan Bo Cong Haiying Xu Yuan Ni Yuling Li Daning Shi 《Plasmonics (Norwell, Mass.)》2014,9(5):1007-1014
Au nanorod (Au NR) is one of the most studied colloidal nanostructures for its tunable longitudinal surface plasmon resonance (SPRL) property in the near infrared region. And surface coating Au NRs into core-shell nanostructures is particularly important for further investigation and possible applications. In this paper, Au NRs colloids were synthesized using an improved seed method. Then as-prepared Au NRs were coated with SiO2 to form a core-shell nanostructure (Au@SiO2) with different shell thickness. And the influence of SiO2 shell on the SPRL of Au NRs was investigated based on the experimental results and FDTD simulations. Under the 808 nm laser irradiating, the stability of Au@SiO2 was studied. Compared with Au NRs, the Au@SiO2 is stable with increasing laser power (up to 8 W), whereas Au NRs undergo a shape deformation from rod to spherical nanoparticle when the laser power is 5 W. The high stability and tunable optical properties of core-shell structured Au@SiO2, along with advantages of SiO2, show that Au@SiO2 composites are promising in designing plasmonic photothermal properties or further applications in nanomedicine. 相似文献
108.
Xuanyu Tao Yabo Li Haiying Huang Yong Chen Pu Liu Xiangkai Li 《Annals of microbiology》2014,64(2):451-457
Desulfovibrio vulgaris can use lactate as an electron donor and accumulate hydrogen. Hydrogen can also be consumed as an electron donor when lactate is depleted or absent. The aim of this study was to determine whether D. vulgaris has an electron donor preference system between lactate and hydrogen and how this system is regulated. In order to be sure that D. vulgaris was grown under the same conditions except for electron donors, continuous growth mode was conducted and the optical density (600 nm) was kept constant. When 20 mmol/l lactate was the sole electron donor, it was depleted after 9 h of incubation while hydrogen was accumulated to 1,500 ppm. After that, the hydrogen level was decreased to and maintained at 400 ppm. When 1,200 ppm hydrogen was provided as the electron donor, the culture reached an OD of 0.2 after 24 h incubation and hydrogen was consumed to 600 ppm. When 1,200 ppm hydrogen and 20 mmol/l lactate were both present, the lactate was consumed during the first 9 h incubation and hydrogen was accumulated to 1,800 ppm. D. vulgaris used hydrogen as an electron donor after the lactate was depleted and the hydrogen level was decreased to 600 ppm. D. vulgaris has both pathways to utilize lactate and hydrogen as electron donors. It prefers lactate over hydrogen and the system is regulated by lactate starvation. 相似文献
109.
Highly sensitive electrochemiluminescence determination of etamsylate using a low‐cost electrochemical flow‐through cell based on a tris(2, 2'‐bipyridyl)ruthenium(II)–Nafion‐modified carbon paste electrode 下载免费PDF全文
A simple and sensitive electrochemiluminescence (ECL) method for the determination of etamsylate has been developed by coupling an electrochemical flow‐through cell with a tris(2,2'‐bipyridyl)ruthenium(II) (Ru(bpy)32+)–Nafion‐modified carbon electrode. It is based on the oxidized Ru(bpy)32+ on the electrode surface reacting with etamsylate and producing an excellent ECL signal. Under optimized experimental conditions, the proposed method allows the measurement of etamsylate over the range of 8–1000 ng/mL with a correlation coefficient of r = 0.9997 (n = 7) and a limit of detection of 1.57 ng/mL (3σ), the relative standard deviation (RSD) for 1000 ng/mL etamsylate (n = 7) is 0.96%. The immobilized Ru(bpy)32+ carbon paste electrode shows good electrochemical and photochemical stability. This method is rapid, simple, sensitive and has good reproducibility. It has been successfully applied to the determination of the studied etamsylate in pharmaceutical preparations with satisfactory results. The possible ECL reaction mechanism has also been discussed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
110.
Ming Liao Jianying Shi Lirong Huang Yong Gao Aihua Tan Chunlei Wu Zheng Lu Xiaobo Yang Shijun Zhang Yanlin Hu Xue Qin Jianling Li Gang Chen Jianfeng Xu Zengnan Mo Haiying Zhang 《PloS one》2014,9(8)
Only a small proportion of genetic variation in serum ferritin has been explained by variant genetic studies, and genome-wide association study (GWAS) for serum ferritin has not been investigated widely in Chinese population. We aimed at exploring the novel genetic susceptibility to serum ferritin, and performed this two stage GWAS in a healthy Chinese population of 3,495 men aged 20–69 y, including 1,999 unrelated subjects in the first stage and 1,496 independent individuals in the second stage. Serum ferritin was measured with electrochemiluminescence immunoassay, and DNA samples were collected for genotyping. A total of 1,940,243 SNPs were tested by using multivariate linear regression analysis. After adjusting for population stratification, age and BMI, the rs5742933 located in the 5′UTR region of PMS1 gene on chromosome 2 was the most significantly associated with ferritin concentrations (P-combined = 2.329×10−10) (β = −0.11, 95% CI: −0.14, −0.07). Moreover, this marker was about 200kb away from the candidate gene SLC40A1 which is responsible for iron export. PMS1 gene was the novel genetic susceptibility to serum ferritin in Chinese males and its relation to SLC40A1 needs further study. 相似文献