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91.
Yoshihisa Shimizu Chiaki Yoshikawa Junji Suzuki Jun Qiu Edith van den Bosch 《Biotechnology letters》2016,38(3):403-408
Objective
When polymer brushes are applied as the inner coating for artificial blood vessels, they may induce unwanted responses in vascular endothelial cells continuously exposed to the polymer surface. Accordingly, we have examined the in vitro effect of non-biofouling concentrated polymer brushes (CPBs) on pro-inflammatory and angiogenic responses of human umbilical vein endothelial cells (HUVECs).Results
Micro-patterned CPBs were prepared on silicon wafers using biocompatible polymers, poly(poly(ethylene glycol)methyl ether methacrylate) (PPEGMA) and poly(2-hydroxyethyl methacrylate) (PHEMA). HUVECs were cultured on PPEGMA-CPBs and PHEMA-CPBs with different channel widths (20, 50, and 80 µm) and analyzed for mRNA expression of the pro-inflammatory cytokines IL-6 and IL-8 and angiogeneic vascular endothelial growth factor (VEGF). Irrespective of channel width, PHEMA-CPBs reduced the expression of all target genes, whereas PPEGMA-CPBs reduced VEGF and did not affect IL-6 and IL-8 levels.Conclusion
Micro-patterned CPBs, irrespective of chemical structure or adhesion area, do not induce the expression of important pro-inflammatory and angiogenic mediators in endothelial cells.92.
93.
Rui Liu Limei Qiu Xin Zhao Huan Zhang Lingling Wang Zhanhui Hou 《Marine Biology Research》2016,12(2):146-157
Bacterial disease has caused high mortality of breeding molluscs from 2009 to 2011 in the Changhai area (Dalian, China). Vibrio spp. and Pseudomonas spp. have been detected as major pathogenic agents for aquatic animals in this area. In the present study, four virulence genes including vsm, toxR, aprX and carA were targeted to develop a real-time PCR assay for the quantitative detection of Vibrio splendidus, V. parahaemolyticus, Pseudomonas fluorescens and P. putida, respectively. The sensitivity and specificity of the assays were verified by experimental samples, and the variation tendencies of pathogenic V. splendidus, V. parahaemolyticus, P. fluorescens and P. putida strains from June to September were also detected in mollusc farming waters during 2011–2014. The concentration of V. splendidus increased from June to July, reduced in August, and then increased again in September. The highest count of V. parahaemolyticus appeared in July, and then dramatically decreased from August to September. Conversely, the counts of P. fluorescens and P. putida remained at lower levels from June to August, and then dramatically peaked in September. All four pathogenic bacteria displayed similar fluctuation tendencies of count variation in each year, and their concentrations were found to have a correlation with the average annual temperature. The variation tendency of pathogenic bacteria with temperature suggested that temperature was one of the most important factors to regulate the bacterial growth in a farming area, which could further provide information for the early warning of disease outbreak by using a convenient real-time PCR assay. 相似文献
94.
以走马胎(Ardisia gigantifolia)幼嫩茎段为外植体, 通过腋芽增殖的方式进行组织培养和快速繁殖研究。结果表明, 培养基MS+1.0 mg·L -1 6-BA+0.2 mg·L -1NAA和MS+0.5 mg·L -1 ZT均可用于腋芽的诱导和前期继代培养, 诱导率分别为89.3%和85.7%; 芽增殖最佳培养基为MS+0.5 mg·L -16-BA+0.1 mg·L -1ZT+0.1 mg·L -1NAA, 增殖系数为4.3倍; 根诱导最佳培养基为1/2MS+1.5 mg·L -1 IAA+1.0 mg·L -1 NAA, 生根率达92.3%, 且根系发达, 植株健壮; 生根苗在混合基质园土:泥炭:珍珠岩=3:1:1 (v/v/v )中移栽成活率为82%。该研究建立了走马胎种苗的组织培养快速繁殖技术体系, 且可应用于规模化生产。 相似文献
95.
Seven new polyhydroxypregnane glycosides, named cynotophyllosides P–V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid . Their structures were elucidated by a variety of spectroscopic techniques, as well as acid‐catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A‐ and LPS‐induced proliferation of mice splenocytes. Immunoenhancing (for 1 , 9 ) and immunosuppressive (for 2 ) activities were observed. Furthermore, cynotophylloside R ( 3 ) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 μg/ml. 相似文献
96.
Huanran Feng Yuan‐Qiu‐Qiang Yi Xin Ke Jing Yan Yamin Zhang Xiangjian Wan Chenxi Li Nan Zheng Zengqi Xie Yongsheng Chen 《Liver Transplantation》2019,9(12)
Two new nonfullerene small molecule acceptors (NF‐SMAs) AT‐NC and AT‐4Cl based on heptacyclic anthracene(cyclopentadithiophene) (AT) core and different electron‐withdrawing end groups are designed and synthesized. Although the two new acceptor molecules use two different end groups, naphthyl‐fused indanone (NINCN) and chlorinated INCN (INCN‐2Cl) demonstrate similar light absorption. AT‐4Cl with chlorinated INCN as end groups are shifted significantly due to the strong electron‐withdrawing ability of chlorine atoms. Thus, desirable Voc and photovoltaic performance are expected to be achieved when polymer PBDB‐T is used as the electron donor with AT‐NC as the acceptor, and fluorinated analog PBDB‐TF with down‐shifted energy levels is selected to blend with AT‐4Cl. Consequently, the device based on PBDB‐TF:AT‐4Cl yields a high power conversion efficiency of 13.27% with a slightly lower Voc of 0.901 V, significantly enhanced Jsc of 19.52 mA cm?2 and fill factor of 75.5% relative to the values based on PBDB‐T:AT‐NC. These results demonstrate that the use of a new electron‐rich AT core, together with energy levels modulations by end‐group optimizations enabling the match with polymer donors, is a successful strategy to construct high‐performance NF‐SMAs. 相似文献
97.
98.
The residues of phenothiazines and benzodiazepines in foods of animal origin are dangerous to consumers. For inspection of their abuses, this study for the first time reported on the use of a chemiluminescence array sensor for the simultaneous determination of four phenothiazines and five benzodiazepines in pig urine. Two molecularly imprinted polymers were coated in different wells of a conventional 96‐well microtiter plate as the recognition reagents. After sample loading, the absorbed analytes were initiated directly by using an imidazole enhanced bis(2,4,6‐trichlorophenyl)oxalate–hydrogen peroxide system to emit light. The assay process consisted of only one sample‐loading step prior to data acquisition, so one test was finished within 10 min. The limits of detection for the nine drugs in the pig urine were in a range of 0.1 to 0.6 pg/mL, and the recoveries from the fortified blank urine samples were in a range of 80.3 to 95%. Furthermore, the sensor could be reused six times. Therefore, this sensor could be used as a simple, rapid, sensitive and reusable tool for routine screening for residues of phenothiazines and benzodiazepines in pig urine. 相似文献
99.