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981.
982.
Wee‐Kee Tan Yiqian Ang Teck‐Kwang Lim Tit‐Meng Lim Prakash Kumar Chiang‐Shiong Loh Qingsong Lin 《Electrophoresis》2015,36(19):2473-2481
Preparation of proteins from salt‐gland‐rich tissues of mangrove plant is necessary for a systematic study of proteins involved in the plant's unique desalination mechanism. Extraction of high‐quality proteins from the leaves of mangrove tree species, however, is difficult due to the presence of high levels of endogenous phenolic compounds. In our study, preparation of proteins from only a part of the leaf tissues (i.e. salt gland‐rich epidermal layers) was required, rendering extraction even more challenging. By comparing several extraction methods, we developed a reliable procedure for obtaining proteins from salt gland‐rich tissues of the mangrove species Avicennia officinalis. Protein extraction was markedly improved using a phenol‐based extraction method. Greater resolution 1D protein gel profiles could be obtained. More promising proteome profiles could be obtained through 1D‐LC‐MS/MS. The number of proteins detected was twice as much as compared to TUTS extraction method. Focusing on proteins that were solely present in each extraction method, phenol‐based extracts contained nearly ten times more proteins than those in the extracts without using phenol. The approach could thus be applied for downstream high‐throughput proteomic analyses involving LC‐MS/MS or equivalent. The proteomics data presented herein are available via ProteomeXchange with identifier PXD001691. 相似文献
983.
Single nucleotide polymorphisms of mitochondrial DNA HVS‐I and HVS‐II in Chinese Bai ethnic group
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Feng Chen Cai‐Yong Yin Xiao‐Qin Qian Han‐Ting Fan Ya‐Jun Deng Yu‐Dang Zhang Hao‐Tian Meng Chun‐Mei Shen Chun‐Hua Yang Rui Jin Bo‐Feng Zhu Peng Xu 《Electrophoresis》2015,36(6):930-936
For forensic and population genetic purposes, a total of 125 unrelated volunteers’ blood samples were collected from Chinese Bai ethnic minority group to analyze sequence variation of two hypervariable segments (HVS‐I and HVS‐II) in the mitochondrial DNA control region. Comparing the HVS‐I and HVS‐II sequences of the 125 Chinese Bais to the Anderson reference sequence, we found 86 polymorphic loci in HVS‐I and 40 in HVS‐II in mitochondrial DNA sequences of the Chinese Bai ethnic minority group, which defined 93 and 53 different haplotypes, respectively. Haplotype diversity and the mean pairwise differences were 0.992 ± 0.003 and 6.553 in HVS‐I, and 0.877 ± 0.027 and 2.407 in HVS‐II, respectively. We defined four macrohaplogroups R, M, N and D with the proportions ranging from 9.6% to 40.0%. With the analysis of the hypervariable domain from nucleotide 16 180–16 193 in HVS‐I, our study revealed new haplotypes of sequence variations. In addition, the Fst metric, phylogenetic tree, and principal component analysis demonstrated a close genetic relationship between the Bai group and Chinese Han populations from South China, Changsha, and Guangdong. The results support that the Bai group is a multiorigin ethnic minority that has merged with the Chinese Han population. 相似文献
984.
Haiying Yang Zhejian Li Meng Shan Congcong Li Honglan Qi Qiang Gao Jinyi Wang Chengxiao Zhang 《Analytica chimica acta》2015
A highly selective and sensitive electrogenerated chemiluminescence (ECL) biosensor for the detection of prostate PC-3 cancer cells was designed using a prostate specific antibody as a capture probe and ruthenium complex-labelled wheat germ agglutinin as a signal probe. The ECL biosensor was fabricated by covalently immobilising the capture probe on a graphene oxide-coated glassy carbon electrode. Target PC-3 cells were selectively captured on the surface of the biosensor, and then, the signal probe was bound with the captured PC-3 cells to form a sandwich. In the presence of tripropylamine, the ECL intensity of the sandwich biosensor was logarithmically directly proportion to the concentration of PC-3 cells over a range from 7.0 × 102 to 3.0 × 104 cells mL−1, with a detection limit of 2.6 × 102 cells mL−1. The ECL biosensor was also applied to detect prostate specific antigen with a detection limit of 0.1 ng mL−1. The high selectivity of the biosensor was demonstrated in comparison with that of a lectin-based biosensor. The strategy developed in this study may be a promising approach and could be extended to the design of ECL biosensors for highly sensitive and selective detection of other cancer-related cells or cancer biomarkers using different probes. 相似文献
985.
986.
Biocatalytic Synthesis of the Anti‐diabetes Agent‐corosolic Acid by Whole Cells of Microorganisms
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Diabetes is one of the most prevalent and costly global diseases. For diabetes, frequent insulin treatment and synthetic drugs are very expensive and may cause unwanted side effects. Corosolic acid (CA), a natural product, was reported to be efficient in the treatment of diabetes, meanwhile without induction of anti‐insulin antibodies and obesity. The preparation of CA attracted many researchers in the world. This study investigated the biocatalytic synthesis method of CA from ursolic acid by Streptomyces griseus subsp. griseus 4.18. LC? MS analysis demonstrated that 5 day, 125 μg/mL substrate, pH=9 and 10% strain concentration were the appropriate conditions. It is estimated that biocatalysis will contribute to the development of green and sustainable synthetic processes with less time‐consuming and more environmentally friendly. 相似文献
987.
Chiral Separations in Normal‐phase Liquid Chromatography: Updating a Screening Strategy with a Chlorine‐containing Polysaccharide‐based Selector
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Jie Zhou Shanshan Chen Pei Luo Chong Sun Lingchang Meng Qiuzheng Du Fang Sun 《中国化学会会志》2015,62(12):1059-1067
The screening conditions of an existing column and mobile phase selection strategy for chiral compounds in normal‐phase high performance liquid chromatography (NP‐HPLC) were tested for their applicability on Chiralpak IC, which is a chiral stationary phase (CSP) made by immobilising cellulosic tris (3,5‐dichlorophenyl‐carbamate) on silica gel. In this study, the applicability of the optimization steps of the existing separation strategy was examined using 36 compounds representing the three possible resolution situations that occur after screening. The cumulative number of separated compounds is 27 (75.0 %), and the cumulative number of baseline separated compounds is 19 (52.8 %). 相似文献
988.
We reported here for the first time on the use of cotton thread combined with novel gold nanoparticle trimer reporter probe for low-cost, sensitive and rapid detection of a lung cancer related biomarker, human ferritin. A model system comprising ferritin as an analyte and a pair of monoclonal antibodies was used to demonstrate the proof-of-concept on the dry-reagent natural cotton thread immunoassay device. Results indicated that the using of novel gold nanoparticle trimer reporter probe greatly improved the sensitivity comparing with traditional gold nanoparticle reporter probe on the cotton thread immunoassay device. The assay avoids multiple incubation and washing steps performed in most conventional protein analyses. Although qualitative tests are realized by observing the color change of the test zone, quantitative data are obtained by recording the optical responses of the test zone with a commercial scanner and corresponding analysis software. Under optimal conditions, the cotton thread immunoassay device was capable of measuring 10 ng/mL human ferritin under room temperature which is sensitive enough for clinical diagnosis. Moreover, the sample solution employed in the assays is just 8 μL, which is much less than traditional lateral flow strip based biosensors. 相似文献
989.
Paecilomycines A and B,Novel Diterpenoids,Isolated from Insect‐Pathogenic Fungi Paecilomyces sp. ACCC 37762
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Kun Zhou Xiao‐Ling Zhao Li‐Ping Han Meng‐Meng Cao Chuan Chen Bao‐Zhong Shi Du‐Qiang Luo 《Helvetica chimica acta》2015,98(5):642-649
Two new diterpenoids, named paecilomycine A ( 1 ) and paecilomycine B ( 2 ), including a novel skeleton with a five‐membered lactone ring, together with three known labdane diterpenoids, rel‐(1R,3S,4aS,5R,8aS)‐5‐[(3E)‐4‐carboxy‐3‐methylbut‐3‐en‐1‐yl]decahydro‐3‐hydroxy‐1,4a‐dimethyl‐6‐methylidenenaphthalene‐1‐carboxylic acid ( 3 ), botryosphaerin E ( 4 ), and agathic acid ( 5 ), were isolated from solid culture of the insect pathogenic fungi strain Paecilomyces sp. The structures of all compounds were established on the basis of comprehensive spectroscopic studies. The relative configurations of 1 and 2 were determined by single‐crystal X‐ray diffraction analyses. 相似文献
990.