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991.
We demonstrate a novel rapid direct detection method for immunohistochemistry, using a bioluminescent probe. An anti‐CEA antibody‐fused far‐red bioluminescent protein can monitor the accumulation of this type of probe in tumour tissues. The bimodal spectrum (λmax = 460 and 675 nm) of this bioluminescent probe is extremely stable under different conditions of pH and ion concentration. The sensitivity of our bioluminescent labelling was at the same level of enzymatic labelling, e.g. peroxidase, as an indirect system. Our novel technique is simple and can shorten the pretreatment time of paraffin sections to around 30 min. The utility of our bioluminescent labelling covers all imaging in vitro, in vivo and ex vivo, suggesting that our antibody‐fused bioluminescent probe has the potential to detect tumour antigens with a high sensitivity in routine immune histological examinations. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
992.
A highly sensitive and simple method for identifying sulpiride in pharmaceutical formulations and biological fluids is presented. The method is based on increased chemiluminescence (CL) intensity of a luminol–H2O2 system in response to the addition of Cr (III) under alkaline conditions. The CL intensity of the luminol–H2O2–Cr (III) system was greatly enhanced by the addition of sulpiride and the CL intensity was proportional to the concentration of sulpiride in a sample solution. Various parameters affecting the CL intensity were systematically investigated and optimized for determination of the sulpiride in a sample. Under the optimum conditions, the CL intensity was proportional to the concentration of sulpiride in the range of 0.068–4.0 µg/mL, with a good correlation coefficient of 0.997. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 8.50 × 10‐6 µg/mL and 2.83 × 10‐5 µg/mL, respectively. The method presented here produced good reproducibility with a relative standard deviation (RSD) of 2.70% (n = 7). The effects of common excipients and metal ions were studied for their interference effect. The method was validated statistically through recovery studies and successfully applied for the determination of sulpiride in pure form, pharmaceutical preparations and spiked human plasma samples. The percentage recoveries were found to range from 99.10 to 100.05% for pure form, 98.12 to 100.18% for pharmaceutical preparations and 97.9 to 101.4% for spiked human plasma. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
993.
A simple, accurate, precise and validated spectrofluorimetric method is proposed for the determination of two cephalosporins, namely, cefadroxile (cefa) and cefuroxime sodium (cefu) in pharmaceutical formulations. The method is based on a reaction between cephalosporins with 1,2‐naphthoquinone‐4‐sulfonate in alkaline medium, to form fluorescent derivatives that are extracted with chloroform and subsequently measured at 610 and 605 nm after excitation at 470 and 460 nm for cefa and cefu respectively. The optimum experimental conditions have been studied. Beer's law is obeyed over the concentrations of 20–70 ng/mL and 15–40 ng/mL for cefa and cefu, respectively. The detection limits were 4.46 ng/mL and 3.02 ng/mL with a linear regression correlation coefficient of 0.9984 and 0.998, and recoveries ranging 97.50–109.96% and 95.73–98.89% for cefa and cefu, respectively. The effects of pH, temperature, reaction time, 1,2‐naphthoquinone‐4‐sulfonic concentration and extraction solvent on the determination of cefa and cefu, have been examined. The proposed method can be applied for the determination of cefa and cefu in pharmaceutical formulations in quality control laboratories. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
994.
Abstract

Novel 1,3-oxathiolanyl pyrimidine nucleosides with 5-hydroxymethyl substituent were synthesized starting from d-mannose and evaluated for antiviral activities against HIV-1, HSV type 1,2 and HCMV.  相似文献   
995.
996.
Unlike mammals, regenerative model organisms such as amphibians and fish are capable of spinal cord regeneration after injury. Certain key differences between regenerative and nonregenerative organisms have been suggested as involved in promoting this process, such as the capacity for neurogenesis and axonal regeneration, which appear to be facilitated by favorable astroglial, inflammatory and immune responses. These traits provide a regenerative‐permissive environment that the mammalian spinal cord appears to be lacking. Evidence for the regenerative nonpermissive environment in mammals is given by the fact that they possess neural stem/progenitor cells, which transplanted into permissive environments are able to give rise to new neurons, whereas in the nonpermissive spinal cord they are unable to do so. We discuss the traits that are favorable for regeneration, comparing what happens in mammals with each regenerative organism, aiming to describe and identify the key differences that allow regeneration. This comparison should lead us toward finding how to promote regeneration in organisms that are unable to do so. genesis 51:529–544. © 2013 Wiley Periodicals, Inc.  相似文献   
997.
Regulators of G‐protein Signaling (Rgs) proteins are the members of a multigene family of GTPase‐accelerating proteins (GAP) for the Galpha subunit of heterotrimeric G‐proteins. Rgs proteins play critical roles in the regulation of G protein couple receptor (GPCR) signaling in normal physiology and human diseases such as cancer, heart diseases, and inflammation. Rgs12 is the largest protein of the Rgs protein family. Some in vitro studies have demonstrated that Rgs12 plays a critical role in regulating cell differentiation and migration; however its function and mechanism in vivo is largely unknown. Here, we generated a floxed Rgs12 allele (Rgs12flox/flox) in which the exon 2, containing both PDZ and PTB_PID domains of Rgs12, was flanked with two loxp sites. By using the inducible Mx1‐cre and Poly I:C system to specifically delete Rgs12 at postnatal 10 days in interferon‐responsive cells including monocyte and macrophage cells, we found that Rgs12 mutant mice had growth retardation with the phenotype of increased bone mass. We further found that deletion of Rgs12 reduced osteoclast numbers and had no significant effect on osteoblast formation. Thus, Rgs12flox/flox conditional mice provide a valuable tool for in vivo analysis of Rgs12 function and mechanism through time‐ and cell‐specific deletion of Rgs12. genesis 51:201–209, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
998.
Porcine induced pluripotent stem cells (iPSCs) provide useful information for translational research. The quality of iPSCs can be assessed by their ability to differentiate into various cell types after chimera formation. However, analysis of chimera formation in pigs is a labor‐intensive and costly process, necessitating a simple evaluation method for porcine iPSCs. Our previous study identified mouse embryonic stem cell (ESC)‐specific hypomethylated loci (EShypo‐T‐DMRs), and, in this study, 36 genes selected from these were used to evaluate porcine iPSC lines. Based on the methylation profiles of the 36 genes, the iPSC line, Porco Rosso‐4, was found closest to mouse pluripotent stem cells among 5 porcine iPSCs. Moreover, Porco Rosso‐4 more efficiently contributed to the inner cell mass (ICM) of blastocysts than the iPSC line showing the lowest reprogramming of the 36 genes (Porco Rosso‐622‐14), indicating that the DNA methylation profile correlates with efficiency of ICM contribution. Furthermore, factors known to enhance iPSC quality (serum‐free medium with PD0325901 and CHIR99021) improved the methylation status at the 36 genes. Thus, the DNA methylation profile of these 36 genes is a viable index for evaluation of porcine iPSCs. genesis 51:763–776. © 2013 Wiley Periodicals, Inc.  相似文献   
999.
We have assessed the efficacy of the recently developed CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR‐associated) system for genome modification in the amphibian Xenopus tropicalis. As a model experiment, targeted mutations of the tyrosinase gene were verified, showing the expected albinism phenotype in injected embryos. We further tested this technology by interrupting the six3 gene, which is required for proper eye and brain formation. Expected eye and brain phenotypes were observed when inducing mutations in the six3 coding regions, as well as when deleting the gene promoter by dual targeting. We describe here a standardized protocol for genome editing using this system. This simple and fast method to edit the genome provides a powerful new reverse genetics tool for Xenopus researchers. genesis 51:835–843. © 2013 Wiley Periodicals, Inc.  相似文献   
1000.
The Cam River mouth (Haiphong Province) is one of the main river mouths of the Red River System, which is one of the most important water resources in Northern Vietnam. Over the past 50 years, the strong socio-economic development in the area has caused a considerable contamination with heavy metals (Co, Cr, Cu, Mn, Ni, Pb, and Zn) and arsenic. In this study, the vertical and horizontal distributions of heavy metals and arsenic in sediments from the Cam River mouth were investigated. In addition, the history, origin, and degree of contamination were assessed. Normalized (with respect to Al) heavy metal and arsenic concentrations in sediment cores and absolute dates obtained from the 137Cs analysis were used to reconstruct the pollution history of the river mouth. As, Cu, Mn, Pb, and Zn concentrations increase rapidly by approximately two times or more from 1954 to 1975, and then remain nearly unchanged from 1975 until 2008, whereas Co, Cr, and Ni concentrations slightly increase from 1954 until 2008. In addition, background values for heavy metals and arsenic have also been determined with regard to the period before 1954. In the study area, Co, Cr, Cu, Ni, Mn, and Zn are evaluated as minorly enriched, whereas As and Pb are classified as moderately enriched. Generally, the anthropogenic activities in the Haiphong harbor and industrial zone locally contribute to the contamination by heavy metals and arsenic in the Cam River mouth.  相似文献   
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