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81.
A highly sensitive chemiluminescence (CL) immunoassay was incorporated into a low‐cost microfluidic paper‐based analytical device (μ‐PAD) to fabricate a facile paper‐based CL immunodevice (denoted as μ‐PCLI). This μ‐PCLI was constructed by covalently immobilizing capture antibody on a chitosan membrane modified μ‐PADs, which was developed by simple wax printing methodology. TiO2 nanoparticles coated multiwalled carbon nanotubes (TiO2/MWCNTs) were synthesized as an amplification catalyst tag to label signal antibody (Ab2). After sandwich‐type immunoreactions, the TiO2/MWCNTs were captured on the surface of μ‐PADs to catalyze the luminol‐p‐iodophenol‐H2O2 CL system, which produced an enhanced CL emission. Using prostate‐specific antigen as a model analyte, the approach provided a good linear response range from 0.001 to 20 ng/mL with a low detection limit of 0.8 pg/mL under optimal conditions. This μ‐PCLI showed good reproducibility, selectivity and stability. The assay results of prostate‐specific antigen in clinical serum samples were in good agreement with that obtained by commercially used electrochemiluminescence methods at the Cancer Research Center of Shandong Tumor Hospital (Jinan, Shandong Province, China). This μ‐PCLI could be very useful to realize highly sensitive, qualitative point‐of‐care testing in developing or developed countries. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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83.
Zhou Jiang Weijun Liu Yuhui Wang Zhen Gao Ge Gao Xiaowei Wang 《RNA (New York, N.Y.)》2013,19(12):1745-1754
MicroRNAs (miRNAs) are involved in a variety of human diseases by simultaneously suppressing many gene targets. Thus, the therapeutic value of miRNAs has been intensely studied. However, there are potential limitations with miRNA-based therapeutics such as a relatively moderate impact on gene target regulation and cellular phenotypic control. To address these issues, we proposed to design new chimeric small RNAs (aiRNAs) by incorporating sequences from both miRNAs and siRNAs. These aiRNAs not only inherited functions from natural miRNAs, but also gained new functions of gene knockdown in an siRNA-like fashion. The improved efficacy of multifunctional aiRNAs was demonstrated in our study by design and testing of an aiRNA that inherited the functions of both miR-200a and an AKT1-targeting siRNA for simultaneous suppression of cancer cell motility and proliferation. The general principles of aiRNA design were further validated by engineering new aiRNAs mimicking another miRNA, miR-9. By regulating multiple cellular functions, aiRNAs could be used as an improved tool over miRNAs to target disease-related genes, thus alleviating our dependency on a limited number of miRNAs for the development of RNAi-based therapeutics. 相似文献
84.
Zheyong Huang Yunli Shen Hongmin Zhu Jianfeng Xu Yanan Song Xinying Hu Zhang Shuning Xiangdong Yang Aijun Sun Juying Qian Junbo Ge 《Experimental Animals》2013,62(3):197-203
Cell delivery via the retrograde coronary route boasts less vessel embolism, myocardial
injury, and arrhythmogenicity when compared with those via antegrade coronary
administration or myocardial injection. However, conventional insertion into the coronary
sinus and consequent bleeding complication prevent its application in small animals. To
overcome the complication of bleeding, we described a modified coronary retroinfusion
technique via the jugular vein route in rats with myocardial infarction (MI). A flexible
wire with a bent end was inserted into the left internal jugular vein and advanced slowly
along the left superior vena cava. Under direct vision, the wire was run into the left
cardiac vein by rotating the wire and changing the position of its tip. A fine tube was
then advanced along the wire to the left cardiac vein. This modified technique showed less
lethal hemorrhage than the conventional technique. Retroinfusion via transjugular catheter
enabled efficient fluid or cell dissemination to the majority areas of the free wall of
the left ventricle, covering the infarcted anterior wall. In conclusion, transjugular
cardiac vein catheterization may make retrocoronary infusion a more safe and practical
route for delivering cell, drug, and gene therapy into the infarcted myocardium of
rats. 相似文献
85.
The persistent terrestrial carbon sink regulates long‐term climate change, but its size, location, and mechanisms remain uncertain. One of the most promising terrestrial biogeochemical carbon sequestration mechanisms is the occlusion of carbon within phytoliths, the silicified features that deposit within plant tissues. Using phytolith content–biogenic silica content transfer function obtained from our investigation, in combination with published silica content and aboveground net primary productivity (ANPP) data of leaf litter and herb layer in China's forests, we estimated the production of phytolith‐occluded carbon (PhytOC) in China's forests. The present annual phytolith carbon sink in China's forests is 1.7 ± 0.4 Tg CO2 yr ? 1, 30% of which is contributed by bamboo because the production flux of PhytOC through tree leaf litter for bamboo is 3–80 times higher than that of other forest types. As a result of national and international bamboo afforestation and reforestation, the potential of phytolith carbon sink for China's forests and world's bamboo can reach 6.8 ± 1.5 and 27.0 ± 6.1 Tg CO2 yr?1, respectively. Forest management practices such as bamboo afforestation and reforestation may significantly enhance the long‐term terrestrial carbon sink and contribute to mitigation of global climate warming. 相似文献
86.
Xiang-Yang Ge Yan Xu Xiang Chen 《Journal of industrial microbiology & biotechnology》2013,40(3-4):345-352
This study describes a novel strategy to improve the glycolysis flux of Saccharomyces cerevisiae at high temperature. The TSL1 gene-encoding regulatory subunit of the trehalose synthase complex was overexpressed in S. cerevisiae Z-06, which increased levels of trehalose synthase activity in extracts, enhanced stress tolerance and glucose consuming rate of the yeast cells. As a consequence, the final ethanol concentration of 185.5 g/L was obtained at 38 °C for 36 h (with productivity up to 5.2 g/L/h) in 7-L fermentor, and the ethanol productivity was 92.7 % higher than that of the parent strain. The results presented here provide a novel way to enhance the carbon metabolic flux at high temperature, which will be available for the purposes of producing other primary metabolites of commercial interest using S. cerevisiae as a host. 相似文献
87.
To investigate potential differences in stone composition with regard to the type of Primary Hyperoxaluria (PH), and in relation to the patient’s medical therapy (treatment naïve patients versus those on preventive medication) we examined twelve kidney stones from ten PH I and six stones from four PH III patients. Unfortunately, no PH II stones were available for analysis. The study on this set of stones indicates a more diverse composition of PH stones than previously reported and a potential dynamic response of morphology and composition of calculi to treatment with crystallization inhibitors (citrate, magnesium) in PH I. Stones formed by PH I patients under treatment are more compact and consist predominantly of calcium-oxalate monohydrate (COM, whewellite), while calcium-oxalate dihydrate (COD, weddellite) is only rarely present. In contrast, the single stone available from a treatment naïve PH I patient as well as stones from PH III patients prior to and under treatment with alkali citrate contained a wide size range of aggregated COD crystals. No significant effects of the treatment were noted in PH III stones. In disagreement with findings from previous studies, stones from patients with primary hyperoxaluria did not exclusively consist of COM. Progressive replacement of COD by small COM crystals could be caused by prolonged stone growth and residence times in the urinary tract, eventually resulting in complete replacement of calcium-oxalate dihydrate by the monohydrate form. The noted difference to the naïve PH I stone may reflect a reduced growth rate in response to treatment. This pilot study highlights the importance of detailed stone diagnostics and could be of therapeutic relevance in calcium-oxalates urolithiasis, provided that the effects of treatment can be reproduced in subsequent larger studies. 相似文献
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89.
Background
Platelet-rich products (PRP) are widely used for rotator cuff tears. However, whether platelet-rich products produce superior clinical or radiological outcomes is controversial. This study aims to use meta-analysis to compare clinical and radiological outcomes between groups with or without platelet-rich products.Methods
The Pubmed, Embase, and Cochrane library databases were searched for relevant studies published before April 20, 2013. Studies were selected that clearly reported a comparison between the use or not of platelet-rich products. The Constant, ASES, UCLA, and SST scale systems and the rotator cuff retear rate were evaluated. The weighted mean differences and relative risks were calculated using a fixed-effects model.Results
Seven studies were enrolled in this meta-analysis. No significant differences were found for the Constant scale (0.73, 95% CI, −1.82 to 3.27, P = 0.58), ASES scale (−2.89, 95% CI, −6.31 to 0.53, P = 0.1), UCLA scale (−0.79, 95% CI, −2.20 to 0.63, P = 0.28), SST scale (0.34, 95% CI, −0.01 to 0.69, P = 0.05), and the overall rotator cuff retear rate (0.71, 95% CI, 0.48 to 1.05, P = 0.08). Subgroup analysis according to the initial tear size showed a lower retear rate in small- and medium-sized tears (0.33, 95% CI, 0.12 to 0.91, P = 0.03) after platelet-rich product application but no difference for large- and massive-sized tears (0.86, 95% CI, 0.60 to 1.23, P = 0.42).Conclusion
In conclusion, the meta-analysis suggests that the platelet-rich products have no benefits on the overall clinical outcomes and retear rate for the arthroscopic repair of full-thickness rotator cuff tears. However, a decrease occurred in the rate of retears among patients treated with PRP for small- and medium-sized rotator cuff tears but not for large- and massive-sized tears.Level of Evidence
Level II 相似文献90.