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Find video protocols related to scientific articles indexed in Pubmed.
Increased CD4+CD25+ regulatory T cells correlate with poor short-term outcomes in hepatitis B virus-related acute-on-chronic liver failure patients.
J Microbiol Immunol Infect
PUBLISHED: 03-15-2015
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The roles of CD4(+)CD25(+) regulatory T cells (Treg) in chronicity of hepatitis B virus (HBV) infection have been confirmed. We aimed to explore alteration of Treg in patients with HBV-related acute-on-chronic liver failure (ACLF).
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Strained olefin enables triflic anhydride mediated direct dehydrative glycosylation.
Org. Biomol. Chem.
PUBLISHED: 11-05-2014
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For the first time, we demonstrated that Tf2O mediated direct dehydrative glycosylation was possible simply with strained olefins, and other typical bases were inhibitors of this reaction. We optimized the glycosylation conditions and found that typical benzyl protected 1-OH pyranosyl donors and certain alcohol acceptors were suitable for our glycosylation system. Furthermore, we found that complete 1,2-trans selectivity and a wider acceptor scope could be achieved with 2-O-Bz 3,4,6-tri-O-Bn pyranosyl donors.
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Molecular Characterization and Phylogenetic Analysis of Two Novel Regio-specific Flavonoid Prenyltransferases from Morus alba and Cudrania tricuspidata.
J. Biol. Chem.
PUBLISHED: 11-02-2014
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Prenylated flavonoids are attractive specialized metabolites with a wide range of biological activities and are distributed in several plant families. The prenylation catalyzed by prenyltransferases (PTs) represents a Friedel-Crafts alkylation of the flavonoid skeleton in the biosynthesis of natural prenylated flavonoids and contributes to the structural diversity and biological activities of these compounds. To date, all identified plant flavonoid prenyltransferases (FPTs) have been identified in Leguminosae. In the present study, two new FPTs, MaIDT and CtIDT, were identified from moraceous plants Morus alba and Cudrania tricuspidata, respectively. MaIDT and CtIDT shared low levels of homology with the leguminous FPTs. MaIDT and CtIDT are predicted to be membrane-bound proteins with predicted transit peptides, seven transmembrane regions and conserved functional domains that are similar to other homogentisate prenyltransferases. Recombinant MaIDT and CtIDT were able to regioselectively introduce dimethylallyl diphosphate (DMAPP) into the A ring of three flavonoids with different skeleton types (chalcones, isoflavones and flavones). Phylogenetic analysis revealed that MaIDT and CtIDT are distantly related to their homologs in Leguminosae, which suggests that FPTs in Moraceae and Leguminosae might have evolved independently. MaIDT and CtIDT represent the first two non-Leguminosae FPTs to be identified in plants and could thus lead to the identification of additional evolutionarily varied FPTs in other non-Leguminosae plants and could elucidate the biosyntheses of prenylated flavonoids in various plants. Furthermore, MaIDT and CtIDT might be used for regiospecific prenylation of flavonoids to produce bioactive compounds for potential therapeutic applications due to their high efficiency and catalytic promiscuity.
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The Effect of Early and Late Tracheotomy on Outcomes in Patients: A Systematic Review and Cumulative Meta-analysis.
Otolaryngol Head Neck Surg
PUBLISHED: 10-12-2014
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To compare the effect of early tracheotomy (ET) and late tracheotomy (LT) on ventilator-associated pneumonia (VAP) incidence and short-term mortality in critically ill patients who received mechanical ventilation.
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[Effect of different compatibility of zhizi dahuang decoction on pharmacokinetics of naringenin and hesperetin].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-04-2014
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An HPLC-UV method was developed for the determination of total naringenin and total hesperetin in rat plasma after oral administration of Citrus aurantium Immaturus extracts and Zhizi Dahuang decoction. Plasma samples were pretreated with liquid-liquid extraction procedure and acid hydrolysis method was used for converting conjugated naringenin and hesperetin to their respective free forms. Plasma samples were separated on a C18 column (4.6 mm x 150 mm, 5 microm), using 0.1% phosphoric acid and methanol as mobile phase at a flow rate of 1.0 mL x min(-1) with gradient elution. DAS 2.0 software was applied to calculate the pharmacokinetic parameters while the SPSS 16.0 software was used for statistical analysis. Significant differences were observed, the C(max) AUC(0-t) of total naringenin in ZS group was 73.5% and 65.9% higher than those in ZZDHD group, respectively; the C(max), AUC(0-t) of total hesperetin in ZS group was 63.5% and 119.1% higher than those in ZZDHD group, respectively. There is a obvious decrease in C(max) and AUC(0-t) of total naringenin and total hesperetin after compatibility and their pharmacokinetic characteristics changed greatly due to the combination of other herbs. The established method was rapid, sensitive, selective and accurate, and it could be applied in the determination of total naringenin and total hesperetin in rat plasma.
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Circumferential decompression via the posterior approach for the surgical treatment of multilevel thoracic ossification of the posterior longitudinal ligaments: a single institution comparative study.
Chin. Med. J.
PUBLISHED: 10-02-2014
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The treatment strategies for multilevel thoracic ossification of the posterior longitudinal ligaments (T-OPLL) were rarely reported. The aim of this study was to investigate the clinical outcomes and complications of circumferential decompression for multilevel T-OPLL and compare two different methods in the management of the OPLL (resection or floating).
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[Regulation of syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid biosynthesis in cell suspension cultures of Saussurea involucrata].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-24-2014
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Syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid are three main bioactive ingredients in herbs of Saussurea involucrata with various pharmacological properties, while their contents are very low. In this study, the biosynthesis of syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid in the cell suspension cultures of S. involucrata were regulated by feeding carbon sources and precursors, which resulted in a great increase of the contents and yields of the above three bioactive ingredients. After 16 days of fermentation, the yields of syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid reached 339.0, 225.3, 512.7 mg x L(-1), respectively. Meanwhile, their contents increased up to 67.9, 1.9, 10.6 times of wild medicinal material, respectively. The results provided a solid basis for further studies on application of cell suspension cultures of S. involucrata for large-scale production of bioactive compounds syringin, chlorogenic acid and 1,5-dicaffeoylquinic acid.
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The Rho kinase inhibitor Y-27632 facilitates the differentiation of bone marrow mesenchymal stem cells.
J. Mol. Histol.
PUBLISHED: 09-02-2014
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The selective in vitro expansion and differentiation of multipotent stem cells are critical steps in cell-based regenerative therapies, but technical challenges have limited cell yield and thus the success of these potential treatments. The Rho GTPases and downstream Rho kinases (Rho coiled-coil kinases or ROCKs) are central regulators of cytoskeletal dynamics during the cell cycle and thus help determine the balance between stem cells self-renewal, lineage commitment, and apoptosis. Here, we examined if suppression of ROCK signaling enhances the efficacy of bone marrow-derived mesenchymal stem cells (BMSCs) differentiation into neurons and neuroglial cells. BMSCs were cultured in epidermal growth factor (EGF, 10 µg/l) and basic fibroblastic growth factor (bFGF, 10 µg/l) in the presence or absence of the Rho kinase inhibitor Y-27632 (10 µM). The expression levels of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were detected by immunofluorescence and Western blotting. The average number of NSE-positive cells increased from 83.20 ± 8.677 (positive ratio 0.2140 ± 0.0119) to 109.20 ± 8.430 (positive ratio 0.3193 ± 0.0161) per visual field in the presence of Y-27632, while GFAP-positive cell number increased from 96.30 ± 8.486 (positive ratio 0.18 ± 0.0152) to 107.50 ± 8.683 (positive ratio 0.27 ± 0.0115) (P < 0.05 for both). Both NSE and GFAP protein expression levels were enhanced significantly by Y-27632 treatment (NSE: 0.74 ± 0.05 vs. 1.03 ± 0.06; GFAP: 0.64 ± 0.08 vs. 0.97 ± 0.05, both P < 0.01) as indicated by Western blots. The Rho kinase inhibitor Y-27632 concomitant with EGF and bFGF stimulation promotes BMSC differentiation into neural cells. Control of Rho kinase activity may enhance the efficiency of stem cell-based treatments for neurodegenerative diseases.
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Restoration of S100A4 expression enhances invasive and metastatic potentials of COLO16 cutaneous squamous cancer cells.
Cancer Biomark
PUBLISHED: 08-30-2014
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S100A4 promotes cancer metastasis but is frequently silenced in human cutaneous squamous cell carcinomas/c-SCCs due to DNA methylation, which may explain the less metastasized property of c-SCCs.
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Mammalian target of rapamycin signaling is involved in the vasculogenic mimicry of glioma via hypoxia-inducible factor-1?.
Oncol. Rep.
PUBLISHED: 08-29-2014
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The mammalian target of rapamycin (mTOR) is a crucial regulator in malignant gliomas. Vasculogenic mimicry (VM) describes functional channels established by highly malignant tumor cells that is different from endothelium-lined blood vessels. Our previous studies confirmed the existence and clinical significance of VM in medulloblastoma and glioblastoma. In the present study, by immunohistochemical and CD34/PAS histochemical double-staining, 34 cases (26.8%) with VM structures were identified among a total of 127 glioma cases, and these VM structures were associated with mTOR expression in the glioma specimens. In vitro, U87 malignant glioblastoma cells formed tube structures similar to HUVECs on Matrigel in 3D culture, and mTOR-specific inhibitor rapamycin inhibited VM formation in the U87 malignant glioblastoma cells under both normoxia and hypoxia. In addition, rapamycin and mTOR siRNA inhibited molecules in the signaling cascade of VM formation, particularly HIF-1?. Taken together, our results demonstrated that mTOR signaling is involved in VM formation, and may be a potential therapeutic target for gliomas.
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Physiological Significance of Helical Flow in the Arterial System and its Potential Clinical Applications.
Ann Biomed Eng
PUBLISHED: 08-29-2014
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Helical flow in the human aorta is possibly a typical example of 'form follows function' in the vascular system. The helical blood flow may provide guaranties for the inner surface of the ascending aortic wall to get smooth and even washing by the blood so that atherosclerotic plaques can hardly form in the area of the ascending aorta. It has been documented that the phenomenon of helical flow of blood is not just localized in the ascending aorta, it also exists in several large arteries and veins as well. Preliminary studies demonstrated the widely existing helical flow might play positive physiological roles in facilitating blood flow transport, suppressing disturbed blood flow, preventing the accumulation of atherogenic low density lipoproteins on the luminal surfaces of arteries, enhancing oxygen transport from the blood to the arterial wall and reducing the adhesion of blood cells on the arterial surface. These roles of helical blood flow may lessen the burden of arteries and protect the arteries from the pathology of atherosclerosis, thrombosis, and intimal hyperplasia. The great development of time-resolved three-dimensional phase contrast MRI (flow-sensitive 4D-MRI) and the advent of dimensionless indices such as helical flow index proposed to characterize helical flow make clinic quantification of the helical flow in the human large arteries possible. Moreover, researchers probed into the possibility to apply the mechanism of helical flow to the design of vascular interventions to reduce thrombus formation and intimal hyperplasia caused by abnormal flow conditions.
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Molecular characterization of an infectious bronchitis virus strain isolated from northern China in 2012.
Arch. Virol.
PUBLISHED: 08-29-2014
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This study reports the complete genome sequence of an infectious bronchitis virus (CK/CH/SD/121220, KJ128295) isolated in 2012 from Shandong Province in northern China. The genome is 27,666 nt long, comprising six genes and 5' and 3' untranslated regions. The full-length genome of the CK/CH/SD/121220 isolate had the highest nucleotide sequence identity (96.7 %) to the YX10 strain. Sites of recombination were identified in the genes 1ab, S, 5a, 5b and N, with their putative parental strains belonging to the QX- and YN-type subgroups, which are already circulating in China. Our findings suggest an important role played by recombination in IBV evolution.
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[A novel HIF-1 inhibitor--manassantin A derivative LXY6099 inhibits tumor growth].
Yao Xue Xue Bao
PUBLISHED: 08-26-2014
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Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor on hypoxia responses in mammalian tissues. HIF-1 plays as a positive factor in solid tumor and leads to hypoxia-driven responses that enhance its downstream gene expression for tumor growth and survival. LXY6099 was obtained by the structural modification and optimization of manassantin A (MA) as a high potent HIF-1 inhibitor. Antitumor activity of LXY6099 was observed in this study. LXY6099 with an IC50 value of 2.46 x 10(-10) mol x L(-1) showed more sensitive inhibition activity to HIF-1 than that of MA detected by reporter gene assay (> 100 folds). It showed strong inhibition on the growth of human solid tumor cell lines. Furthermore, LXY6099 exhibited significant antitumor activity against established human tumor xenografts in nu/nu mice with treatment of MX-1 breast cancer. Thus, LXY6099 as a novel HIF-1 inhibitor could be further developed into anti-cancer agents.
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Evaluation of up-converting phosphor technology-based lateral flow strips for rapid detection of Bacillus anthracis Spore, Brucella spp., and Yersinia pestis.
PLoS ONE
PUBLISHED: 08-21-2014
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Bacillus anthracis, Brucella spp., and Yersinia pestis are zoonotic pathogens and biowarfare- or bioterrorism-associated agents that must be detected rapidly on-site from various samples (e.g., viscera and powders). An up-converting phosphor technology-based lateral flow (UPT-LF) strip was developed as a point-of-care testing (POCT) to satisfy the requirements of first-level emergency response. We developed UPT-LF POCT to quantitatively detect the three pathogens within 15 min. Sample and operation-error tolerances of the assay were comprehensively evaluated. The sensitivity of UPT-LF assay to bacterial detection reached 10(4) cfu · mL(-1) (100 cfu/test), with a linear quantitative range of 4 to 6 orders of magnitude. Results revealed that the UPT-LF assay exhibited a high specificity with the absence of false-positive results even at 10(9) cfu · mL(-1) of non-specific bacterial contamination. The assay could tolerate samples with a wide pH range (2 to 12), high ion strengths (? 4 mol · L(-1) of NaCl), high viscosities (? 25 mg · mL(-1) of PEG20000 or ? 20% of glycerol), and high concentrations of bio-macromolecule (? 200 mg · mL(-1) of bovine serum albumin or ? 80 mg · mL(-1) of casein). The influence of various types of powders and viscera (fresh and decomposed) on the performance of UPT-LF assay was determined. The operational error of liquid measurement exhibited few effects on sensitivity and specificity. The developed UPT-LF POCT assay is applicable under field conditions with excellent tolerance to sample complexity and operational error.
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Joint analysis of three genome-wide association studies of esophageal squamous cell carcinoma in Chinese populations.
Chen Wu, Zhaoming Wang, Xin Song, Xiao-Shan Feng, Christian C Abnet, Jie He, Nan Hu, Xian-Bo Zuo, Wen Tan, Qimin Zhan, Zhibin Hu, Zhonghu He, Weihua Jia, Yifeng Zhou, Kai Yu, Xiao-Ou Shu, Jian-Min Yuan, Wei Zheng, Xue-Ke Zhao, She-Gan Gao, Zhi-Qing Yuan, Fu-You Zhou, Zong-Min Fan, Ji-Li Cui, Hong-Li Lin, Xue-Na Han, Bei Li, Xi Chen, Sanford M Dawsey, Linda Liao, Maxwell P Lee, Ti Ding, You-Lin Qiao, Zhihua Liu, Yu Liu, Dianke Yu, Jiang Chang, Lixuan Wei, Yu-Tang Gao, Woon-Puay Koh, Yong-Bing Xiang, Ze-Zhong Tang, Jin-Hu Fan, Jing-jing Han, Sheng-Li Zhou, Peng Zhang, Dong-Yun Zhang, Yuan Yuan, Ying Huang, Chunling Liu, Kan Zhai, Yan Qiao, Guangfu Jin, Chuanhai Guo, Jianhua Fu, Xiaoping Miao, Changdong Lu, Haijun Yang, Chaoyu Wang, William A Wheeler, Mitchell Gail, Meredith Yeager, Jeff Yuenger, Er-Tao Guo, Ai-li Li, Wei Zhang, Xue-Min Li, Liang-Dan Sun, Bao-Gen Ma, Yan Li, Sa Tang, Xiu-Qing Peng, Jing Liu, Amy Hutchinson, Kevin Jacobs, Carol Giffen, Laurie Burdette, Joseph F Fraumeni, Hongbing Shen, Yang Ke, Yixin Zeng, Tangchun Wu, Peter Kraft, Charles C Chung, Margaret A Tucker, Zhi-Chao Hou, Ya-Li Liu, Yan-Long Hu, Li Wang, Guo Yuan, Li-Sha Chen, Xiao Liu, Teng Ma, Hui Meng, Li Sun, Xin-Min Li, Xiu-Min Li, Jian-Wei Ku, Ying-Fa Zhou, Liu-Qin Yang, Zhou Wang, Yin Li, Qirenwang Qige, Wen-jun Yang, Guang-Yan Lei, Long-qi Chen, En-Min Li, Ling Yuan, Wen-Bin Yue, Ran Wang, Lu-Wen Wang, Xue-Ping Fan, Fang-Heng Zhu, Wei-Xing Zhao, Yi-min Mao, Mei Zhang, Guo-Lan Xing, Ji-Lin Li, Min Han, Jing-Li Ren, Bin Liu, Shu-Wei Ren, Qing-Peng Kong, Feng Li, Ilyar Sheyhidin, Wu Wei, Yan-Rui Zhang, Chang-Wei Feng, Jin Wang, Yu-Hua Yang, Hong-Zhang Hao, Qi-De Bao, Bao-Chi Liu, Ai-Qun Wu, Dong Xie, Wan-Cai Yang, Liang Wang, Xiao-Hang Zhao, Shu-Qing Chen, Jun-Yan Hong, Xue-Jun Zhang, Neal D Freedman, Alisa M Goldstein, Dongxin Lin, Philip R Taylor, Li-dong Wang, Stephen J Chanock.
Nat. Genet.
PUBLISHED: 08-17-2014
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We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) of esophageal squamous cell carcinoma (ESCC) in individuals of Chinese ancestry (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.82-0.88; P = 7.72 × 10(-20)) and rs1642764 at 17p13.1 (per-allele OR = 0.88, 95% CI = 0.85-0.91; P = 3.10 × 10(-13)). rs7447927 is a synonymous SNP in TMEM173, and rs1642764 is an intronic SNP in ATP1B2, near TP53. Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR = 1.33, 95% CI = 1.22-1.46; P = 1.99 × 10(-10)). Our joint analysis identifies new ESCC susceptibility loci overall as well as a new locus unique to the population in the Taihang Mountain region at high risk of ESCC.
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Genome-wide identification of citrus ATP-citrate lyase genes and their transcript analysis in fruits reveals their possible role in citrate utilization.
Mol. Genet. Genomics
PUBLISHED: 08-13-2014
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ATP-citrate lyase (ACL, EC4.1.3.8) catalyzes citrate to oxaloacetate and acetyl-CoA in the cell cytosol, and has important roles in normal plant growth and in the biosynthesis of some secondary metabolites. We identified three ACL genes, CitACL?1, CitACL?2, and CitACL?1, in the citrus genome database. Both CitACL?1 and CitACL?2 encode putative ACL ? subunits with 82.5 % amino acid identity, whereas CitACL?1 encodes a putative ACL ? subunit. Gene structure analysis showed that CitACL?1 and CitACL?2 had 12 exons and 11 introns, and CitACL?1 had 16 exons and 15 introns. CitACL?1 and CitACL?1 were predominantly expressed in flower, and CitACL?2 was predominantly expressed in stem and fibrous roots. As fruits ripen, the transcript levels of CitACL?1, CitACL?1, and/or CitACL?2 in cultivars 'Niuher' and 'Owari' increased, accompanied by significant decreases in citrate content, while their transcript levels decreased significantly in 'Egan No. 1' and 'Iyokan', although citrate content also decreased. In 'HB pummelo', in which acid content increased as fruit ripened, and in acid-free pummelo, transcript levels of CitACL?2, CitACL?1, and/or CitACL?1 increased. Moreover, mild drought stress and ABA treatment significantly increased citrate contents in fruits. Transcript levels of the three genes were significantly reduced by mild drought stress, and the transcript level of only CitACL?1 was significantly reduced by ABA treatment. Taken together, these data indicate that the effects of ACL on citrate use during fruit ripening depends on the cultivar, and the reduction in ACL gene expression may be attributed to citrate increases under mild drought stress or ABA treatment.
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A novel algorithm for imbalance data classification based on neighborhood hypergraph.
ScientificWorldJournal
PUBLISHED: 08-11-2014
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The classification problem for imbalance data is paid more attention to. So far, many significant methods are proposed and applied to many fields. But more efficient methods are needed still. Hypergraph may not be powerful enough to deal with the data in boundary region, although it is an efficient tool to knowledge discovery. In this paper, the neighborhood hypergraph is presented, combining rough set theory and hypergraph. After that, a novel classification algorithm for imbalance data based on neighborhood hypergraph is developed, which is composed of three steps: initialization of hyperedge, classification of training data set, and substitution of hyperedge. After conducting an experiment of 10-fold cross validation on 18 data sets, the proposed algorithm has higher average accuracy than others.
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Analysis of fluorescent ceramide and sphingomyelin analogs: a novel approach for in vivo monitoring of sphingomyelin synthase activity.
Lipids
PUBLISHED: 08-10-2014
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A novel sensitive high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method was developed for real-time monitoring of relative sphingomyelin synthase (SMS) activity based on the measurement of a fluorescent ceramide (Cer) analog and its metabolite, a fluorescent sphingomyelin (CerPCho) analog, in plasma. Analyses were conducted using HPLC-FLD following a protein precipitation procedure. The chromatographic separations were carried out on an Agilent C18 RP column (150 × 4.6 mm, 5 ?m) based on a methanol-0.1 % trifluoroacetic acid aqueous solution (88:12, by vol) elution at a flow-rate of 1 mL/min. The limit of quantification in plasma was 0.05 ?M for both the fluorescent Cer analog and its metabolite. Significant differences in the fluorescent Cer analog and its metabolite concentration ratio at 5 min were found between vehicle control group and three D2 (a novel SMS inhibitor) dose groups (P < 0.05). Dose-dependent effects (D2 doses: 0, 2.5, 5, 10 mg/kg) were observed. Our method could be used to detect relative SMS activity in biochemical assays and to screen potential SMS inhibitors in vivo. D2 was found to be a potent SMS inhibitor in vivo, and may have a potential antiatherosclerotic effect, which is under further study. D609 was also selected as another model SMS inhibitor to validate our newly developed method.
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Evaluation of the influence of sulfur-fumigation on the pharmacokinetics of four active ingredients in Si Wu Tang.
J Sep Sci
PUBLISHED: 08-08-2014
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Sulfur-fumigation may induce the decrease or the chemical transformation of some active ingredients of traditional Chinese medicines in vitro. Whether sulfur-fumigation can cause the pharmacokinetic changes of the active ingredients in vivo is related to the efficacy and the safety of Chinese medicines' application clinically. A sensitive, specific, and accurate method for the simultaneous determination of paeoniflorin, ferulic acid, senkyunolide A, and senkyunolide I in rat plasma by ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometry was developed to evaluate the influence of sulfur-fumigation to Si Wu Tang for the first time. Each compound was extracted from the plasma samples by liquid-liquid extraction with ethyl acetate, and the chromatographic separation was accomplished on an Agilent Extend C18 column with a linear gradient elution. The mass spectrometric detection and analysis were performed by using an AB Sciex triple quadrupole 5500 mass spectrometer in multiple reaction monitoring mode. The validated method was successfully applied to a pharmacokinetic study of four compounds in rats after oral administration of sun-dried and sulfur-fumigated Si Wu Tang. The results provided a meaningful basis for evaluating the affection of sulfur-fumigation to the clinical application and the efficacy of Si Wu Tang This article is protected by copyright. All rights reserved.
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Dynamic Resting State Functional Connectivity in Awake and Anesthetized Rodents.
Neuroimage
PUBLISHED: 08-08-2014
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Since its introduction, resting-state functional magnetic resonance imaging (rsfMRI) has been a powerful tool for investigating functional neural networks in both normal and pathological conditions. When measuring resting-state functional connectivity (RSFC), most rsfMRI approaches do not consider its temporal variations and thus only provide the averaged RSFC over the scan time. Recently, there has been a surge of interest to investigate the dynamic characteristics of RSFC in humans, and promising results have been yielded. However, our knowledge regarding the dynamic RSFC in animals remains sparse. In the present study we utilized the single-volume co-activation method to systematically study the dynamic properties of RSFC within the networks of infralimbic cortex (IL) and primary somatosensory cortex (S1) in both awake and anesthetized rats. Our data showed that both IL and S1 networks could be decomposed into several spatially reproducible but temporally changing co-activation patterns (CAPs), suggesting that dynamic RSFC was indeed a characteristic feature in rodents. In addition, we demonstrated that anesthesia profoundly impacted the dynamic RSFC of neural circuits subserving cognitive and emotional functions but had less effects on sensorimotor systems. Finally, we examined the temporal characteristics of each CAP, and found that individual CAPs exhibited consistent temporal evolution patterns. Together, these results suggest that dynamic RSFC might be a general phenomenon in vertebrate animals. In addition, this study has paved the way for further understanding the alterations of dynamic RSFC in animal models of brain disorders.
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Use of non-contact hopping probe ion conductance microscopy to investigate dynamic morphology of live platelets.
Platelets
PUBLISHED: 08-08-2014
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Abstract Circulating platelets are anucleated and multi-functional cells that participate in hemostasis and arterial thrombosis. Multiple ligands and mechanical forces activate platelets, leading to cytoskeletal rearrangement and dramatic shape-changes. Such dramatic changes in platelets membrane structures are commonly detected by optical and electron microscopy after platelets are fixed. We have recently developed a method to study the membrane morphology of live platelets using Hopping Probe Ion Conductance Microscopy (HPICM). We have successfully used this technology to study the process of platelet microvesiculation upon exposure to selective agonists. Here, we further discussed technical details of using HPICM to study platelet biology and compared results from HPICM to those from conventional atomic force microscopy and scanning electron microscopy. This method offers several advantages over current technologies. First, it monitors morphological changes of platelets in response to agonists in real time. Second, platelets can be repeatedly scanned over time without damages brought by heat and prolong light exposure. Third, there is no direct contact with platelet surface so that there will no or minimal mechanical damages brought by a cantilever of a conventional atomic force microscopy. Finally, it offers the potential to study platelet membrane ion channels, which have been technically challenging up-to-date. Our data show that HPICM has high-resolution in delineating changes of platelet morphology in response to stimulations and could help to unravel the complex role of platelet in thrombus formation.
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Molecular crowding-based imprinted monolithic column for capillary electrochromatography.
Electrophoresis
PUBLISHED: 08-04-2014
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Molecular crowding is a new approach to stabilizing binding sites and improving molecular recognition. In this work, the concept was applied to the preparation of imprinted monolithic columns for capillary electrochromatography (CEC). The imprinted monolithic column was synthesized using a mixture of d-zopiclone (d-ZOP)(template), methacrylic acid, ethylene glycol dimethacrylate, and poly (methyl methacrylate)(PMMA)(molecular crowding agent). The resulting PMMA-based imprinted capillary was able to separate ZOP enantiomers in CEC mode. The resolution of enantiomer separation achieved on the d-ZOP-imprinted monolithic column was up to 2.09. Some polymerization factors, such as template-monomer molar ratio, functional monomer-crosslinker molar ratio and the composition of the porogen, on the imprinting effect of resulting MIP monolithic column were systematically investigated. Chromatographic parameters, including pH values, the content of acetonitrile and the salt concentration on chiral separation were also studied. The results indicated the addition of PMMA resulted in MIPs with superior retention properties and excellent selectivity for d-ZOP, as compared to the MIPs prepared without addition of the crowding-inducing agent. The results revealed that molecular crowding is an effective method for the preparation of a highly efficient MIP stationary phase for chiral separation in CEC. This article is protected by copyright. All rights reserved.
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Lack of effects of HER-2/neu on prognosis in colorectal cancer: a meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 08-02-2014
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The prognostic value of human epidermal growth factor receptor-2 (HER-2/neu) for survival of patients with colorectal cancer (CRC) is still ambiguous. We therefore performed a meta-analysis to evaluate its prognostic significance.
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Flurbiprofen improves dysfunction of T-lymphocyte subsets and natural killer cells in cancer patients receiving post-operative morphine analgesia.
Int J Clin Pharmacol Ther
PUBLISHED: 07-31-2014
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Acute pain can lead to immune dysfunction, which can be partly ameliorated by successful pain management. Opioids, which are widely used for analgesia, can result in the deterioration of immune function. This study aimed to investigate the influence of morphine with or without flurbiprofen as post-operative analgesics on the immune systems of patients undergoing gastric cancer surgery.
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Origin of myofibroblasts in the fibrotic liver in mice.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-29-2014
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Hepatic myofibroblasts are activated in response to chronic liver injury of any etiology to produce a fibrous scar. Despite extensive studies, the origin of myofibroblasts in different types of fibrotic liver diseases is unresolved. To identify distinct populations of myofibroblasts and quantify their contribution to hepatic fibrosis of two different etiologies, collagen-?1(I)-GFP mice were subjected to hepatotoxic (carbon tetrachloride; CCl4) or cholestatic (bile duct ligation; BDL) liver injury. All myofibroblasts were purified by flow cytometry of GFP(+) cells and then different subsets identified by phenotyping. Liver resident activated hepatic stellate cells (aHSCs) and activated portal fibroblasts (aPFs) are the major source (>95%) of fibrogenic myofibroblasts in these models of liver fibrosis in mice. As previously reported using other methodologies, hepatic stellate cells (HSCs) are the major source of myofibroblasts (>87%) in CCl4 liver injury. However, aPFs are a major source of myofibroblasts in cholestatic liver injury, contributing >70% of myofibroblasts at the onset of injury (5 d BDL). The relative contribution of aPFs decreases with progressive injury, as HSCs become activated and contribute to the myofibroblast population (14 and 20 d BDL). Unlike aHSCs, aPFs respond to stimulation with taurocholic acid and IL-25 by induction of collagen-?1(I) and IL-13, respectively. Furthermore, BDL-activated PFs express high levels of collagen type I and provide stimulatory signals to HSCs. Gene expression analysis identified several novel markers of aPFs, including a mesothelial-specific marker mesothelin. PFs may play a critical role in the pathogenesis of cholestatic liver fibrosis and, therefore, serve as an attractive target for antifibrotic therapy.
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Novel characterization of Radix Angelicae Dahuricae before and after the sulfur-fumigation process by combining high performance liquid chromatographic fingerprint and multi-ingredients determination.
Pharmacogn Mag
PUBLISHED: 07-24-2014
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Harmful sulfur-fumigation processing method is abused during Radix Angelicae Dahuricae preparation. However, the analytical technique characterizing Radix Angelicae Dahuricae before and after the sulfur-fumigation process is absent.
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Analysis of the influence of sulfur-fumigation on the volatile components of Angelicae sinensis Radix by comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry.
Pharmacogn Mag
PUBLISHED: 07-24-2014
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Sulfur-fumigation of Angelicae sinensis Radix causes changes in the structure and composition of volatile components. These changes alter the curative effect and the quality of A. sinensis Radix.
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Learning to Track Multiple Targets.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 07-23-2014
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Monocular multiple-object tracking is a fundamental yet under-addressed computer vision problem. In this paper, we propose a novel learning framework for tracking multiple objects by detection. First, instead of heuristically defining a tracking algorithm, we learn that a discriminative structure prediction model from labeled video data captures the interdependence of multiple influence factors. Given the joint targets state from the last time step and the observation at the current frame, the joint targets state at the current time step can then be inferred by maximizing the joint probability score. Second, our detection results benefit from tracking cues. The traditional detection algorithms need a nonmaximal suppression postprocessing to select a subset from the total detection responses as the final output and a large number of selection mistakes are induced, especially under a congested circumstance. Our method integrates both detection and tracking cues. This integration helps to decrease the postprocessing mistake risk and to improve performance in tracking. Finally, we formulate the entire model training into a convex optimization problem and estimate its parameters using the cutting plane optimization. Experiments show that our method performs effectively in a large variety of scenarios, including pedestrian tracking in crowd scenes and vehicle tracking in congested traffic.
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Resveratrol protects neurons and the myocardium by reducing oxidative stress and ameliorating mitochondria damage in a cerebral ischemia rat model.
Cell. Physiol. Biochem.
PUBLISHED: 07-08-2014
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Resveratrol has shown potent antioxidant activity in ischemia models. The present study was performed to determine whether resveratrol protects against cerebral ischemia-induced neuronal and myocardial injury by interfering with mitochondrial homeostasis.
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Hydrogen-free amorphous silicon with no tunneling states.
Phys. Rev. Lett.
PUBLISHED: 07-08-2014
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The ubiquitous low-energy excitations, known as two-level tunneling systems (TLSs), are one of the universal phenomena of amorphous solids. Low temperature elastic measurements show that e-beam amorphous silicon (a-Si) contains a variable density of TLSs which diminishes as the growth temperature reaches 400?°C. Structural analyses show that these a-Si films become denser and more structurally ordered. We conclude that the enhanced surface energetics at a high growth temperature improved the amorphous structural network of e-beam a-Si and removed TLSs. This work obviates the role hydrogen was previously thought to play in removing TLSs in the hydrogenated form of a-Si and suggests it is possible to prepare "perfect" amorphous solids with "crystal-like" properties for applications.
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DCE-MRI assessment of the effect of Epstein-Barr virus-encoded latent membrane protein-1 targeted DNAzyme on tumor vasculature in patients with nasopharyngeal carcinomas.
BMC Cancer
PUBLISHED: 07-02-2014
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EBV-encoded latent membrane protein 1 (EBV-LMP1) is an important oncogenic protein for nasopharyngeal carcinoma (NPC) and has been shown to engage a plethora of signaling pathways. Correspondingly, an LMP1-targeted DNAzyme was found to inhibit the growth of NPC cells both in vivo and in vitro by suppressing cell proliferation and inducing apoptosis. However, it remains unknown whether an LMP1-targeted DNAzyme would affect the vasculature of NPC. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has been applied in the clinical trials of anti-angiogenic drugs for more than ten years, and Ktrans has been recommended as a primary endpoint. Therefore, the objective of the current study was to use DCE-MRI to longitudinally study the effect of an EBV-LMP1-targeted DNAzyme on the vasculature of patients with NPC.
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Aerobic copper-catalyzed oxidative [6C+1C] annulation: an efficient route to seven-membered carbocycles.
Chem. Commun. (Camb.)
PUBLISHED: 06-26-2014
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It has been revealed for the first time that co-promoted by CuCl and NaH in the presence of molecular oxygen (air), the reaction of dicinnamoyl ketene dithioacetals as the acyclic C6 synthons with ethyl cyanoacetate gives functionalized seven-membered carbocycles. A mechanism is proposed involving a tandem Michael addition-intramolecular radical cyclization-benzyl C(sp(3))-H bond oxidation.
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Enhanced accumulation of LDLs within the venous graft wall induced by elevated filtration rate may account for its accelerated atherogenesis.
Atherosclerosis
PUBLISHED: 06-22-2014
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To test the hypothesis that the venous graft when implanted in an arterial bypass might endure a significantly elevated water filtration rate, leading to fast infiltration/accumulation of low-density lipoproteins (LDLs) within the graft wall and hence the accelerated atherogenesis.
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Silencing of EEF2K (eukaryotic elongation factor-2 kinase) reveals AMPK-ULK1-dependent autophagy in colon cancer cells.
Autophagy
PUBLISHED: 06-19-2014
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EEF2K (eukaryotic elongation factor-2 kinase), also known as Ca (2+)/calmodulin-dependent protein kinase III, functions in downregulating peptide chain elongation through inactivation of EEF2 (eukaryotic translation elongation factor 2). Currently, there is a limited amount of information on the promotion of autophagic survival by EEF2K in breast and glioblastoma cell lines. However, the precise role of EEF2K in carcinogenesis as well as the underlying mechanism involved is still poorly understood. In this study, contrary to the reported autophagy-promoting activity of EEF2K in certain cancer cells, EEF2K is shown to negatively regulate autophagy in human colon cancer cells as indicated by the increase of LC3-II levels, the accumulation of LC3 dots per cell, and the promotion of autophagic flux in EEF2K knockdown cells. EEF2K negatively regulates cell viability, clonogenicity, cell proliferation, and cell size in colon cancer cells. Autophagy induced by EEF2K silencing promotes cell survival and does not potentiate the anticancer efficacy of the AKT inhibitor MK-2206. In addition, autophagy induced by silencing of EEF2K is attributed to induction of protein synthesis and activation of the AMPK-ULK1 pathway, independent of the suppression of MTOR activity and ROS generation. Knockdown of AMPK or ULK1 significantly abrogates EEF2K silencing-induced increase of LC3-II levels, accumulation of LC3 dots per cell as well as cell proliferation in colon cancer cells. In conclusion, silencing of EEF2K promotes autophagic survival via activation of the AMPK-ULK1 pathway in colon cancer cells. This finding suggests that upregulation of EEF2K activity may constitute a novel approach for the treatment of human colon cancer.
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MicroRNA?224 is downregulated in mucinous cystic neoplasms of the pancreas and may regulate tumorigenesis by targeting Jagged1.
Mol Med Rep
PUBLISHED: 06-09-2014
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The underlying malignancy of mucinous cystic neoplasms (MCNs) of the pancreas most commonly results in patients undergoing surgery. The tumorigenesis of MCNs remains elusive and few studies have investigated the role of specific micro (mi)RNAs in MCNs. The present study focused on the expression of miRNA?224 and its putative target gene Jagged1 (Jag1) to examine its role in tumorigenesis and its suitability as a biomarker for MCNs. Paired tissue samples confirmed by surgical pathology were used to screen the miRNAs involved in MCNs with miRNA microarrays (n=3), and to verify the differentially expressed miRNAs (n=3) and mRNAs of candidate target genes of miRNAs by quantitative polymerase chain reaction (qPCR; n=8). Immunohistochemistry was conducted to confirm the expression and location of Jag1 in the neoplastic epithelial cells. Luciferase assays were performed to confirm the direct target gene of miRNA?224. miRNA microarray analysis revealed that two differentially expressed miRNAs were closely associated with tumorigenesis and pancreatic diseases. The qPCR results revealed that miRNA?224 was more significantly aberrantly expressed and the mRNA expression levels of its putative target gene, Jag1, were upregulated. Strong, diffuse cytoplasmic immunohistochemical labeling of Jag1 with occasional nuclear labeling was detected in the mucinous epithelium. Luciferase reporter activity was significantly reduced by co?transfected miRNA?224 mimics and pMIR?Jag1?wild-type, which suggested that miRNA?224 bound to recognition sites in the 3' untranslated region of its target mRNA, Jag1. In conclusion, miRNA?224 was downregulated in MCNs and may regulate tumorigenesis by targeting Jag1. Further studies investigating the role of miRNAs and functional analysis of epigenetic alterations are required to examine the diagnostic and therapeutic potential of miRNAs in MCNs.
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Total synthesis of (+/-)-4-demethylenglerin A.
J Asian Nat Prod Res
PUBLISHED: 06-09-2014
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Racemic 4-demethylenglerin A (1'), a simplified analog of the guaiane-type sesquiterpene englerin A (1), has been synthesized. The cyclic hydrocarbon core structure was built through modified Metz approach using epoxynitrile cyclization and direct Aldol reaction to prepare the precursor of RCM. The primary cytotoxicity test summarized that C4 methyl has marked impacts on the bioactivity.
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Pseudoxanthoma elasticum: A review of 86 cases in China.
Intractable Rare Dis Res
PUBLISHED: 06-05-2014
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Pseudoxanthoma elasticum (PXE) is a type of rare hereditary disease that affects connective tissue. PXE is found around the world, and its epidemiology in China is still unclear. A database search revealed that 86 patients in total were reported in China from 1985 to 2013. The vast majority of these reports concern single, sporadic cases. This review summarizes the clinical characteristics of PXE and its treatment in China. The hope is to provide a reliable basis for studies on the incidence of PXE and for formulation of relevant policies in the future.
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Bioactive tyrosine-derived cytochalasins from fungus Eutypella sp. D-1.
Chem. Biodivers.
PUBLISHED: 05-16-2014
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Three new cytochalasins Z24 , Z25 , Z26 (1-3, resp.) and one known compound, scoparasin B (4), were isolated from the fungus Eutypella sp. D-1 isolated from the soil of high latitude of the Arctic. The structures of 1-3 were elucidated from spectroscopic data (NMR, MS). These compounds were evaluated for cytotoxic activities against several human tumor cell lines. Among them, compound 1 exhibited moderate cytotoxicity toward human breast cancer MCF-7 cell line with IC50 of 9.33 ?M.
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GuA6DT, a regiospecific prenyltransferase from Glycyrrhiza uralensis, catalyzes the 6-prenylation of flavones.
Chembiochem
PUBLISHED: 04-10-2014
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GuA6DT, a flavonoid prenyltransferase, was identified from Glycyrrhiza uralensis, and it was found that this enzyme regiospecifically transfers a dimethylallyl moiety to apigenin at the C-6 position. A further substrate specificity investigation indicated that the existence of hydroxyls at both the C-5 and C-7 positions of the flavone skeleton is critical for the prenylation. However, substitutions on the B-ring had negligible influence on the prenylation. A comparison of GuA6DT expression in different organs revealed that mRNA is mainly expressed in the aerial parts. Moreover, the GuA6DT mRNA was found to be regulated at the transcriptional level, because methyl jasmonate induced upregulation in cultured cells. GuA6DT is the first identified flavone prenyltransferase to exhibit strict substrate specificity and regiospecificity.
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CD8+HLA-DR+ T cells are increased in patients with severe aplastic anemia.
Mol Med Rep
PUBLISHED: 04-08-2014
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The aim of the present study was to investigate the number and function of CD8+HLA-DR+ cells, which are considered to be activated cytotoxic T lymphocytes (CTLs), in peripheral blood to further examine the pathogenesis of severe aplastic anemia (SAA). Thirty-eight patients with SAA were included in the present study. Patients were screened for paroxysmal nocturnal hemoglobinuria by flow cytometry using anti-CD55 and anti-CD59 antibodies. The number of CD8+HLA-DR+ T cells was measured by three-color flow cytometry using anti-CD8-peridinin chlorophyll, anti-CD3-fluorescein isothiocyanate (FITC) and anti-HLA-DR-FITC antibodies. The expression of perforin, granzyme B, tumor necrosis factor-? (TNF-?) and FasL in CD8+HLA-DR+ T cells was detected by flow cytometry with the appropriate monoclonal antibodies. Total RNA was prepared from purified CD8+HLA-DR+ cells of healthy controls and SAA patients, and then polymerase chain reaction (PCR) was performed. Apoptosis of CD8+HLA-DR+ cells was detected by flow cytometry following staining with Annexin V. The proportion of CD8+HLA-DR+ T cells was analyzed by flow cytometry in peripheral blood and was identified to be significantly higher in untreated SAA than in remission patients and in the controls. The expression of perforin, granzyme B, TNF-? and FasL in CD8+HLA-DR+ T cells was analyzed by flow cytometry and PCR, which revealed increased expression in the untreated SAA group compared with that in the control group. Furthermore, the apoptosis of CD3- bone marrow cells from normal individuals was enhanced following co-culture with CD8+HLA-DR+ T cells from untreated SAA patients. In conclusion, the present study demonstrated that CD8+HLA-DR+ T cells may contribute to bone marrow failure in SAA.
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Identification and transcript analysis of two glutamate decarboxylase genes, CsGAD1 and CsGAD2, reveal the strong relationship between CsGAD1 and citrate utilization in citrus fruit.
Mol. Biol. Rep.
PUBLISHED: 03-26-2014
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Glutamate decarboxylase (GAD, EC 4.1.1.15) has been suggested to be a key, regulatory point in the biosynthesis of ?-aminobutyrate (GABA) and in the utilization of citric acid through GABA shunt pathway. In this study we discovered two GAD genes, named as CsGAD1 and CsGAD2, in citrus genome database and then successfully cloned. Both CsGAD1 and CsGAD2 have a putative pyridoxal 5-phosphate binding domain in the middle region and a putative calmodulin-binding domain at the carboxyl terminus. Gene structure analysis showed that much difference exists in the size of exons and introns or in cis-regulatory elements in promoter region between the two GAD genes. Gene expression indicated that CsGAD1 transcript was predominantly expressed in flower and CsGAD2 transcript was predominantly expressed in fruit juice sacs; in the ripening fruit, CsGAD1 transcript level was at least 2-time higher than CsGAD2 transcript level. Moreover, CsGAD1 transcript level was increased significantly along with the increase of GAD activity and accompanied by a significant decrease of titratable acid (TA), suggesting that it is CsGAD1 rather than CsGAD2 plays a role in the citric acid utilization during fruit ripening. In addition, injection of abscisic acid and foliar spray of K2SO4 significantly increased the TA content of Satsuma mandarin, and significantly decreased GAD activity as well as CsGAD1 transcript, further suggesting the important role of CsGAD1 in the citrate utilization of citrus fruit.
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1,2-trans-1-Dihydroxyboryl benzyl S-glycoside as glycosyl donor.
Carbohydr. Res.
PUBLISHED: 03-16-2014
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Activated by NBS, readily available 1,2-trans-1-dihydroxyboryl benzyl S-glycosides served as glycosyl donors and reacted with certain simple alcohol acceptors to produce pure 1,2-cis-O-glycosides in moderate yields. The boronic acid moiety was revealed essential in the glycosylation for product formation and good anomeric ratio. The preliminary model reactions suggested that glycosyl aryl boronic acids could be used for stereoselective glycosylation.
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Experimental study of the seismic performance of L-shaped columns with 500 MPa steel bars.
ScientificWorldJournal
PUBLISHED: 03-14-2014
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Based on tests on six L-shaped RC columns with 500?MPa steel bars, the effect of axial compression ratios and stirrup spacing on failure mode, bearing capacity, displacement, and curvature ductility of the specimens is investigated. Test results show that specimens with lower axial load and large stirrup characteristic value (larger than about 0.35) are better at ductility and seismic performance, while specimens under high axial load or with a small stirrup characteristic value (less than about 0.35) are poorer at ductility; L-shaped columns with 500?MPa steel bars show better bearing capacity and ductility in comparison with specimens with HRB400 steel bars.
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Traditional Chinese medicine--sea urchin.
Mini Rev Med Chem
PUBLISHED: 02-27-2014
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The sea urchin is an ancient, common, seafloor-dwelling marine invertebrate that belongs to the phylum Echinodermata. There are multiple species of sea urchin with resources that are widely distributed in China, where they were used in ancient times as Traditional Chinese Medicine for treating a variety of diseases. At present, it is known that the shell, spine and gonad of the sea urchin have many medicinal values determined through modern research. In this paper, we summarized the major chemical constituents and medicinal value of the sea urchin.
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Downregulation of neuregulin 1-ErbB4 signaling in parvalbumin interneurons in the rat brain may contribute to the antidepressant properties of ketamine.
J. Mol. Neurosci.
PUBLISHED: 02-27-2014
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Increasing evidence underscores the strong, rapid, and sustained antidepressant properties of ketamine with a good tolerability profile in patients with depression; however, the underlying mechanisms are not fully elucidated. Neuregulin 1 (NRG1) is a bipolar disorder susceptibility gene and a biomarker of major depressive disorder, which regulates pyramidal neuron activity via ErbB4 in parvalbumin interneurons. Moreover, NRG1-ErbB4 signaling is reported to play a key role in the modulation of synaptic plasticity through regulating the neurotransmission. We therefore hypothesized that hypofunction of NRG1-ErbB4 signaling in parvalbumin interneurons is involved in the process of ketamine exerting rapid antidepressant actions in rats subjected to the forced swimming test (FST). The results showed that ketamine reduced the immobility time and latency to feed of rats receiving the FST, downregulated the levels of NRG1, phosphorylated ErbB4 (p-ErbB4), parvalbumin, 67-kDA isoform of glutamic acid decarboxylase (GAD67), gamma-aminobutyric acid (GABA), and upregulated the levels of glutamate in the rat prefrontal cortex and hippocampus. Pretreatment with NRG1 abolished both ketamine's antidepressant effects and ketamine-induced reduction in p-ErbB4, parvalbumin, GAD67, and GABA levels and increase in glutamate levels. These results suggest that the downregulation of NRG1-ErbB4 signaling in parvalbumin interneurons in the rat brain may be a mechanism underlying ketamine's antidepressant properties.
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A new aromatic glycoside from Glehnia littoralis.
Nat. Prod. Res.
PUBLISHED: 02-18-2014
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A new aromatic glycoside (1) was isolated from the roots of Glehnia littoralis Fr. Schmidtex Miq. Its structure was elucidated as vanillic acid 1-O-[?-D-apiofuranosyl-(1 ? 6)-?-D-glucopyranoside] ester mainly by analysing the NMR and MS spectral data. In the in vitro assays, compound 1 displayed some TNF-? secretion inhibitory activity.
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Ordered interface mesoporous immobilized Pd pre-catalyst: En/Pd complexes embedded inside the SBA-15 as an active, reusable and selective phosphine-free hybrid catalyst for the water medium Heck coupling process.
J Colloid Interface Sci
PUBLISHED: 01-15-2014
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A series of Pd-complexes of amine and diamine ligands embedded into the ordered silica mesoporous (PdX2@SBA-15/NY, Y=1, 2) are synthesized. Among them, the covalently bonded Pd(OAc)2/ethylenediamine complex into the SBA-15 exhibit higher activity and selectivity toward Mizoroki-Heck cross-coupling reaction. The Pd(OAc)2@SBA-15/En pre-catalyst could be separated easily from reaction products and used repetitively several times, showing the superiority over the homogeneous catalysts for industrial and chemical applications.
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Determination of xanthatin by ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometry: application to pharmacokinetic study of xanthatin in rat plasma.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 01-07-2014
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A sensitive, specific and rapid ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method has been established to study pharmacokinetic properties of xanthatin. Xanthatin, a compound which belongs to sesquiterpene lactone group, was determined in rat plasma with psoralen as internal standard. Chromatographic separation was performed on an Agilent Zorbax Eclipse plus C18 column (50 mm × 2.1 mm, 3.5 ?m) with gradient elution system at a flow rate of 0.3 mL/min. The mobile phase was composed of methanol and 0.1% formic acid water solution. Analysis was performed under a triple-quadruple tandem mass-spectrometer with an electrospray ionization (ESI) source via the multiple reaction monitoring (MRM) mode to determine xanthatin at [M+H](+)m/z 247.3?m/z 205.2 and that of IS at [M+H](+)m/z 187.1?m/z 143.0 within 5 min. The assay method exhibited good separation of xanthatin from the interference of endogenous substances. The lower limit of quantification (LLOQ) was 1 ng/mL, with a good linearity within the concentration range of 1-5000 ng/mL (r=0.9990). Intra-day and inter-day precision RSD was less than 9.27%; intra-day and inter-day accuracy was 88.48% and 102.25% respectively. The extraction recoveries of xanthatin range from 82.12% to 89.55%, and the extraction RSD was less than 9.01%. The established LC-ESI-MS/MS method is rapid and sensitive, which has been successfully applied to quantify xanthatin in rat plasma for the first time.
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Light-regulated phosphorylation of maize phosphoenolpyruvate carboxykinase plays a vital role in its activity.
Plant Mol. Biol.
PUBLISHED: 01-02-2014
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Phosphoenolpyruvate carboxykinase (PEPCK)-the major decarboxylase in PEPCK-type C4 plants-is also present in appreciable amounts in the bundle sheath cells of NADP-malic enzyme-type C4 plants, such as maize (Zea mays), where it plays an apparent crucial role during photosynthesis (Wingler et al., in Plant Physiol 120(2):539-546, 1999; Furumoto et al., in Plant Mol Biol 41(3):301-311, 1999). Herein, we describe the use of mass spectrometry to demonstrate phosphorylation of maize PEPCK residues Ser55, Thr58, Thr59, and Thr120. Western blotting indicated that the extent of Ser55 phosphorylation dramatically increases in the leaves of maize seedlings when the seedlings are transferred from darkness to light, and decreases in the leaves of seedlings transferred from light to darkness. The effect of light on phosphorylation of this residue is opposite that of the effect of light on PEPCK activity, with the decarboxylase activity of PEPCK being less in illuminated leaves than in leaves left in the dark. This inverse relationship between PEPCK activity and the extent of phosphorylation suggests that the suppressive effect of light on PEPCK decarboxylation activity might be mediated by reversible phosphorylation of Ser55.
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Nitric Oxide Transport in Normal Human Thoracic Aorta: Effects of Hemodynamics and Nitric Oxide Scavengers.
PLoS ONE
PUBLISHED: 01-01-2014
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Despite the crucial role of nitric oxide (NO) in the homeostasis of the vasculature, little quantitative information exists concerning NO transport and distribution in medium and large-sized arteries where atherosclerosis and aneurysm occur and hemodynamics is complex. We hypothesized that local hemodynamics in arteries may govern NO transport and affect the distribution of NO in the arteries, hence playing an important role in the localization of vascular diseases. To substantiate this hypothesis, we presented a lumen/wall model of the human aorta based on its MRI images to simulate the production, transport and consumption of NO in the arterial lumen and within the aortic wall. The results demonstrated that the distribution of NO in the aorta was quite uneven with remarkably reduced NO bioavailability in regions of disturbed flow, and local hemodynamics could affect NO distribution mainly via flow dependent NO production rate of endothelium. In addition, erythrocytes in the blood could moderately modulate NO concentration in the aorta, especially at the endothelial surface. However, the reaction of NO within the wall could only slightly affect NO concentration on the luminal surface, but strongly reduce NO concentration within the aortic wall. A strong positive correlation was revealed between wall shear stress and NO concentration, which was affected by local hemodynamics and NO reaction rate. In conclusion, the distribution of NO in the aorta may be determined by local hemodynamics and modulated differently by NO scavengers in the lumen and within the wall.
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Inhibitory effect of essential oils on Aspergillus ochraceus growth and ochratoxin A production.
PLoS ONE
PUBLISHED: 01-01-2014
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Ochratoxin A (OTA) is a mycotoxin which is a common contaminant in grains during storage. Aspergillus ochraceus is the most common producer of OTA. Essential oils play a crucial role as a biocontrol in the reduction of fungal contamination. Essential oils namely natural cinnamaldehyde, cinnamon oil, synthetic cinnamaldehyde, Litsea citrate oil, citral, eugenol, peppermint, eucalyptus, anise and camphor oils, were tested for their efficacy against A. ochraceus growth and OTA production by fumigation and contact assays. Natural cinnamaldehyde proved to be the most effective against A. ochraceus when compared to other oils. Complete fungal growth inhibition was obtained at 150-250 µL/L with fumigation and 250-500 µL/L with contact assays for cinnamon oil, natural and synthetic cinnamaldehyde, L. citrate oil and citral. Essential oils had an impact on the ergosterol biosynthesis and OTA production. Complete inhibition of ergosterol biosynthesis was observed at ? 100 µg/mL of natural cinnamaldehyde and at 200 µg/mL of citral, but total inhibition was not observed at 200 µg/mL of eugenol. But, citral and eugenol could inhibit the OTA production at ? 75 µg/mL and ? 150 µg/mL respectively, while natural cinnamaldehyde couldn't fully inhibit OTA production at ? 200 µg/mL. The inhibition of OTA by natural cinnamaldehyde is mainly due to the reduction in fungal biomass. However, citral and eugenol could significant inhibit the OTA biosynthetic pathway. Also, we observed that cinnamaldehyde was converted to cinnamic alcohol by A. ochraceus, suggesting that the antimicrobial activity of cinnamaldehyde was mainly attributed to its carbonyl aldehyde group. The study concludes that natural cinnamaldehyde, citral and eugenol could be potential biocontrol agents against OTA contamination in storage grains.
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Myelin basic protein induces neuron-specific toxicity by directly damaging the neuronal plasma membrane.
PLoS ONE
PUBLISHED: 01-01-2014
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The central nervous system (CNS) insults may cause massive demyelination and lead to the release of myelin-associated proteins including its major component myelin basic protein (MBP). MBP is reported to induce glial activation but its effect on neurons is still little known. Here we found that MBP specifically bound to the extracellular surface of the neuronal plasma membrane and induced neurotoxicity in vitro. This effect of MBP on neurons was basicity-dependent because the binding was blocked by acidic lipids and competed by other basic proteins. Further studies revealed that MBP induced damage to neuronal membrane integrity and function by depolarizing the resting membrane potential, increasing the permeability to cations and other molecules, and decreasing the membrane fluidity. At last, artificial liposome vesicle assay showed that MBP directly disturbed acidic lipid bilayer and resulted in increased membrane permeability. These results revealed that MBP induces neurotoxicity through its direct interaction with acidic components on the extracellular surface of neuronal membrane, which may suggest a possible contribution of MBP to the pathogenesis in the CNS disorders with myelin damage.
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The types of hepatic myofibroblasts contributing to liver fibrosis of different etiologies.
Front Pharmacol
PUBLISHED: 01-01-2014
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Liver fibrosis results from dysregulation of normal wound healing, inflammation, activation of myofibroblasts, and deposition of extracellular matrix (ECM). Chronic liver injury causes death of hepatocytes and formation of apoptotic bodies, which in turn, release factors that recruit inflammatory cells (neutrophils, monocytes, macrophages, and lymphocytes) to the injured liver. Hepatic macrophages (Kupffer cells) produce TGF?1 and other inflammatory cytokines that activate Collagen Type I producing myofibroblasts, which are not present in the normal liver. Secretion of TGF?1 and activation of myofibroblasts play a critical role in the pathogenesis of liver fibrosis of different etiologies. Although the composition of fibrogenic myofibroblasts varies dependent on etiology of liver injury, liver resident hepatic stellate cells and portal fibroblasts are the major source of myofibroblasts in fibrotic liver in both experimental models of liver fibrosis and in patients with liver disease. Several studies have demonstrated that hepatic fibrosis can reverse upon cessation of liver injury. Regression of liver fibrosis is accompanied by the disappearance of fibrogenic myofibroblasts followed by resorption of the fibrous scar. Myofibroblasts either apoptose or inactivate into a quiescent-like state (e.g., stop collagen production and partially restore expression of lipogenic genes). Resolution of liver fibrosis is associated with recruitment of macrophages that secrete matrix-degrading enzymes (matrix metalloproteinase, collagenases) and are responsible for fibrosis resolution. However, prolonged/repeated liver injury may cause irreversible crosslinking of ECM and formation of uncleavable collagen fibers. Advanced fibrosis progresses to cirrhosis and hepatocellular carcinoma. The current review will summarize the role and contribution of different cell types to populations of fibrogenic myofibroblasts in fibrotic liver.
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[Diversity of soil bacterial community in banana orchards infected with wilt disease].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
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Six soil samples including 3 wilt disease-infected samples and 3 disease-free samples were collected from the banana orchards in 3 areas in Lingao County, Hainan Province of South China. The soil physical and chemical properties were determined by conventional methods, and the diversity of soil bacterial community was analyzed by terminal restriction fragment length polymorphism (T-RFLP). Then, the relationships between the soil bacterial community composition and the soil physical and chemical properties were investigated. In the same areas, most of the soil physical and chemical properties were poorer in disease-infected than in disease-free banana orchards, with the most obvious difference in soil available P content and pH. The T-RFLP analysis showed the diversity of soil bacterial community was richer in disease-infected than in disease-free banana orchards. The lengths of the dominant T-RFs in the 3 areas were 144, 147 and 233 bp, respectively. Through the comparison with phylogenetic assignment tool, it was deduced that the dominant species in the 3 areas were Bacillus subtilis, Staphylococcus and Eubacterium ruminantium. The distribution of most T-RFs was related to the soil alkaline hydrolyzable N, available K, available P and water content, and the relative abundance of most T-RFs was richer in disease-infected than in disease-free banana orchards.
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[Diagnosis and treatment of unilateral allergic fungal sinusitis].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 12-24-2013
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To investigate the clinical and pathological manifestation, prognosis of unilateral allergic fungal sinusitis (AFS), and to analyze the characters and treatment paradigm of unilateral AFS.
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[Nitrite denitrification characteristics with redox mediator].
Huan Jing Ke Xue
PUBLISHED: 12-03-2013
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This study optimized the nitrite degradation conditions and explored the characteristics of nitrite degradation with redox mediators and nitrite denitrifying bacteria. The results suggested that the optimal condition of nitrite denitrification was 35 degrees C, pH = 8.0, sodium succinate as the carbon source, the C/N rate of 4 and the initial nitrite concentration of 100 mg x L(-1); the optimal AQS concentration was 0. 16 mmol x L(-1); ORP values stabilized around -400 mV to -500 mV with AQS, which were lower than that of controls during the denitrification process; the pH changed with nitrite removal and stabilized at 9 to 10; through the analysis of denitrifying intermediate metabolites, the impact of AQS on nitrite denitrifying process presumably not only played a coenzyme CoQ role but also accelerated the cytochrome transfer electronic process. This study provides the optimal parameters for practical application of the nitrite biodegradation with redox mediator.
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Suppression of WC-independent frequency transcription by RCO-1 is essential for Neurospora circadian clock.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-25-2013
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Rhythmic activation and repression of clock gene transcription is essential for the functions of eukaryotic circadian clocks. In the Neurospora circadian oscillator, frequency (frq) transcription requires the WHITE COLLAR (WC) complex. Here, we show that the transcriptional corepressor regulation of conidiation-1 (RCO-1) is essential for clock function by regulating frq transcription. In rco-1 mutants, both overt and molecular rhythms are abolished, frq mRNA levels are constantly high, and WC binding to the frq promoter is dramatically reduced. Surprisingly, frq mRNA levels were constantly high in the rco-1 wc double mutants, indicating that RCO-1 suppresses WC-independent transcription and promotes WC complex binding to the frq promoter. Furthermore, RCO-1 is required for maintaining normal chromatin structure at the frq locus. Deletion of H3K36 methyltransferase su(var)3-9-enhancer-of-zeste-trithorax-2 (SET-2) or the chromatin remodeling factor CHD-1 leads to WC-independent frq transcription and loss of overt rhythms. Together, our results uncover a previously unexpected regulatory mechanism for clock gene transcription.
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1,3-Carbothiolation of 4-(Trifluoromethyl)-p-Quinols: A New Access to Functionalized (Trifluoromethyl)arenes.
Org. Lett.
PUBLISHED: 11-21-2013
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A new strategy, the 1,3-carbothiolation/aromatization, for the synthesis of functionalized (trifluoromethyl)arenes has been developed that enables the regioselective introduction of two different functional groups onto an "aromatic ring" in the meta-position to each other in a single step.
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[Diversity and in vitro antitumnor activity of endophytic fungi from mangrove plants Xylocarpus].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-09-2013
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A total of 24 biologically pure entophytic fungal strains were isolated from stems, leaves, and seed coats of Xylocarpus plants by repeated purification, and identified with Internal Transcribed Spacer (ITS) rDNA molecular method, which belonging to 14 genera, 11 families, 9 orders and 3 classes. There were differences in genus and species levels among three plant materials from different habitats and species, and it was found that the strains of Phomopsis and Colletotrichum existed in all three plant materials. In vitro assay of antitumor activity by MTT method revealed that the EtOAc extracts of 15 strains exhibited potent antitumor activity. These results suggest that it is of value for further investigation on the above fungal strains.
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Fingerprint Compression Based on Sparse Representation.
IEEE Trans Image Process
PUBLISHED: 11-08-2013
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A new fingerprint compression algorithm based on sparse representation is introduced. Obtaining an overcomplete dictionary from a set of fingerprint patches allows us to represent them as a sparse linear combination of dictionary atoms. In the algorithm, first construct a dictionary for predefined fingerprint image patches. For a new given fingerprint images, represent its patches according to the dictionary by computing l0-minimization and then quantize and encode the representation. In this paper, we consider the effect of various factors on compression results. Three groups of fingerprint images are tested. The experiments demonstrate that our algorithm is efficient compared with several competing compression techniques (JPEG, JPEG 2000 and WSQ), especially at high compression ratios. The experiments also illustrate that the proposed algorithm is robust to extract minutiae.
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Efficient synthesis of trifluoromethylated cyclopentadienes/fulvenes/norbornenes from divinyl ketones.
Org. Biomol. Chem.
PUBLISHED: 11-01-2013
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The synthetic methods of trifluoromethylated cyclopentadienes/fulvenes/norbornenes have been developed using 3-CF3-1,4-dien-3-ols as the synthons, which can be easily prepared by the regiospecific 1,2-addition of the Ruppert–Prakash reagent (TMSCF3) to divinyl ketones. All the reactions are carried out under mild, metal-free conditions to afford the corresponding products in high to excellent yields.
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[Relationship between the expressions of indoleamine 2, 3-dioxygenase in hepatocellular carcinoma and clinicopathological parameters].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-31-2013
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To explore the expressions of indoleamine 2, 3-dioxygenase (IDO) in hepatocellular carcinoma and analyze its relationship with clinicopathological parameters.
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Synthesis of the C18 -Norditerpenoid Alkaloid Neofinaconitine: A Lesson in Convergent Synthesis Planning.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 10-22-2013
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Hexacyclic framework: The total synthesis of the complex C18 -norditerpenoid alkaloid neofinaconitine has been achieved by a convergent approach. This remarkable synthesis featured two Diels-Alder cycloadditions and subsequent Mannich-type N-acyliminium and radical cyclizations to establish the unique hexacyclic core structure of the target molecule.
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[Expression of neuraminidase gene of influenza virus H1N1 in baculovirus-expression system].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 09-19-2013
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To construct the recombinant baculovirus with NA gene of Influenza H1N1 virus.
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Effect of emulsified isoflurane on apoptosis of anoxia-reoxygenation neonatal rat cardiomyocytes.
Asian Pac J Trop Med
PUBLISHED: 09-10-2013
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To explore the effect of emulsified isoflurane (EI) on apoptosis of anoxia-reoxygenation neonatal rat cardiomyocytes and relevant protein expression.
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Effects of thermal pre-treatment on anaerobic co-digestion of municipal biowastes at high organic loading rate.
Chemosphere
PUBLISHED: 08-25-2013
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Anaerobic co-digestion of thermal pre-treated municipal biowaste (MBW) is a field of research that has had limited contributions to date. In this study, laboratory-scale semi-continuously fed anaerobic digesters treating thermally treated and non-treated MBW were operated at high organic loading rates (OLR). The results show that the methanogenesis process was inhibited by the accumulated volatile fatty acids when 30% (w/w) of dewatered activated sludge (DAS) was co-digested with food waste (FW) and fruit/vegetable residue (FVR) at high OLR?10kgvolatilesolidm(-3)d(-1). Co-digestion with thermal hydrolysed DAS can significantly improve digester performance. In contrast to DAS, some adverse effects of thermal pretreatment on the biodegradability of FW and FVR were observed. Therefore, co-digestion of FW, FVR with thermally treated DAS is suggested as an alternative to promote high methane production and process stability.
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Pimarane diterpenes from the Arctic fungus Eutypella sp. D-1.
J. Antibiot.
PUBLISHED: 07-04-2013
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Two new diterpenes, libertellenone G(1) and libertellenone H(2) were isolated from the fungus Eutypella sp. D-1 isolated from the soil of high latitude of Arctic, together with two known pimarane diterpenes (3-4). The structures of 1 and 2 were elucidated from spectroscopic data (nuclear magnetic resonance, mass spectrometry and infrared). These compounds were evaluated for cytotoxic activity against seven human tumor cell lines. Compound 2 showed a range of cytotoxicity between 3.31 and 44.1??M. Compound 1 exhibited antibacterial activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus.The Journal of Antibiotics advance online publication, 30 October 2013; doi:10.1038/ja.2013.104.
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Comparative pharmacokinetics studies of benzoylhypaconine, benzoylmesaconine, benzoylaconine and hypaconitine in rats by LC-MS method after administration of Radix Aconiti Lateralis Praeparata extract and Dahuang Fuzi Decoction.
Biomed. Chromatogr.
PUBLISHED: 07-03-2013
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A rapid and sensitive high-performance liquid chromatography-mass spectrometric (HPLC-MS) method was developed and validated for simultaneous determination of benzoylhypaconine (BHA), benzoylmesaconine (BMA), benzoylaconine (BAC) and hypaconitine (HA) in rat plasma for the first time. The analytes were separated on a Kromasil C18 column with a total running time of 11?min. The validation data demonstrated a sound feasibility for the newly developed method and it was then applied to the pharmacokinetic study of these analytes in rats. Pharmacokinetic behaviors of BHA, BMA, BAC and HA in rats were studied after oral administration of Radix Aconiti Lateralis Praeparata extract (FZ) and Dahuang Fuzi Decoction (DFD). The main parameters for the two groups of subjects were compared, and significant differences between Radix Aconiti Lateralis Praeparata extract group and Dahuang Fuzi Decoction group in calculated parameters, such as the area under the plasma concentration-time from zero to the last quantifiable time-point (AUC0-t ), the area under the plasma concentration-time curve from zero to infinity (AUC0-? ), peak plasma concentration (Cmax ), half-life of elimination (T1/2 ), mean retention time (MRT0-t ), plasma clearance (CL), volume of distribution (Vd ) and time to reach Cmax (Tmax ), were found. After oral administration of DFD, the AUC0-t , AUC0-? and Cmax of BHA, BMA, BAC and HA decreased remarkably (p?
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Assessment of left ventricular dyssynchrony and cardiac function in patients with different pacing modes using real-time three-dimensional echocardiography: Comparison with tissue Doppler imaging.
Exp Ther Med
PUBLISHED: 05-16-2013
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The aim of this study was to evaluate the left ventricular mechanical dyssynchrony (LVMD) and left ventricular dysfunction of patients in AAI, DDD and VVI pacing modes using real-time three-dimensional echocardiography (RT3DE) and tissue Doppler imaging (TDI). The results from the RT3DE and TDI were subsequently compared. Twenty patients with sick sinus syndrome (SSS) who had undergone the implantation of a dual-chamber pacemaker were enrolled in this study and the pacemakers were programmed to AAI, DDD and VVI modes, sequentially. The RT3DE and TDI parameters were obtained following pacing for 24 h in each mode. With RT3DE, we measured the systolic dyssynchrony indices, including Tmsv16-SD%, Tmsv12-SD%, Tmsv6-SD%, Tmsv16-Dif%, Tmsv12-Dif% and Tmsv6-Dif%, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF), respectively. With TDI, we measured the standard deviation and the maximal difference in time from the QRS onset to the peak systolic velocity for 12 left ventricular myocardial segments, i.e. Ts-SD and Ts-Dif, respectively. The results showed that the Tmsv16-SD% and Ts-SD in the AAI mode were significantly lower than those in the DDD and VVI modes (P<0.05); however, there were no significant differences between the DDD and VVI modes (P>0.05). The LVEF in the AAI, DDD and VVI modes was 63.1±8.9, 58.6±11.2 and 57.9±7.6%, respectively (P>0.05). There were negative correlations between the LVEF and Tmsv16-SD% (r, -0.651; P<0.001) and Ts-SD (r, -0.649; P<0.0001). A moderate correlation (r, 0.698; P<0.0001) was observed between Tmsv16-SD% and Ts-SD. The concordance rate between Tmsv16-SD% and Ts-SD for detecting LVMD was 76%. This study showed that DDD and VVI pacing modes induced significant LVMD and a reduction in LVEF, unlike the AAI pacing mode. RT3DE and TDI were capable of objectively evaluating LVMD; however, each method had certain faults. At present, there is a lack of a uniform standard for assessing LVMD; therefore, the use of a variety of techniques and indices is necessary in order to comprehensively evaluate LVMD in patients with different cardiac pacing modes.
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