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Find video protocols related to scientific articles indexed in Pubmed.
Electrochemically driven drug metabolism via a CYP1A2-UGT1A10 bienzyme confined in a graphene nano-cage.
Chem. Commun. (Camb.)
PUBLISHED: 09-30-2014
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A graphene nano-cage with regulatable space for the assembly of a cytochrome P450 1A2-UDP-glucuronosyltransferase 1A10 bienzyme complex has been constructed via a click reaction, and successfully used to study drug sequential metabolism using an electrochemically-driven method.
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Nanocomposites of Graphene and Cytochrome P450 2D6 Isozyme for Electrochemical-Driven Tramadol Metabolism.
Langmuir
PUBLISHED: 09-26-2014
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Cytochrome P450 enzymes (cyt P450s) with an active center of iron protoheme are involved in most clinical drugs metabolism process. Herein, an electrochemical platform for the investigation of drug metabolism in vitro was constructed by immobilizing cytochrome P450 2D6 (CYP2D6) with cyt P450 reductase (CPR) on graphene modified glass carbon electrode. Direct and reversible electron transfer of the immobilized CYP2D6 with the direct electron transfer constant of 0.47 s(-1) and midpoint potential of -0.483 V was obtained. In the presence of substrate tramadol, the electrochemical-driven CYP2D6 mediated catalytic behavior toward the conversion of tramadol to o-demethyl-tramadol was confirmed. The Michaelis-Menten constant (Km(app)) and heterogeneous reaction rate constant during the metabolism of tramadol were calculated to be 23.85 ?M and 1.96 cm s(-1), respectively. The inhibition effect of quinidine on CYP2D6 catalyze-cycle was also investigated. Furthermore, this system was applied to studying the metabolism of other drugs.
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Association of coffee drinking with all-cause mortality: a systematic review and meta-analysis.
Public Health Nutr
PUBLISHED: 08-05-2014
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We aimed to use the meta-analysis method to assess the relationship between coffee drinking and all-cause mortality.
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Enhanced enzymatic reactivity for electrochemically driven drug metabolism by confining cytochrome P450 enzyme in TiO? nanotube arrays.
Anal. Chem.
PUBLISHED: 07-24-2014
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Understanding the enzymatic reaction kinetics that occur within a confined space or interface is a significant challenge. Herein, a nanotube array enzymatic reactor (CYP2C9/Au/TNA) was constructed by electrostatically adsorbing enzyme on the inner wall of TiO2 nanotube arrays (TNAs). TNAs with different dimensions could be fabricated by the anodization of titanium foil through varying the anodization potential or time. The electrical conductivity of TNAs was improved by electrodepositing Au nanoparticles on the inner wall of TNAs. The cytochrome P450 2C9 enzyme (CYP2C9) was confined inside TNAs as a model. The enzymatic activity of CYP2C9 and tolbutamide metabolic yield could be effectively regulated by changing the nanotube diameter and length of TNAs. The enzymatic rate constant k(cat) and apparent Michaelis constant K(m)(app) were determined to be 9.89 s(-1) and 4.8 ?M at the tube inner diameter of about 64 nm and length of 1.08 ?m. The highest metabolic yield of tolbutamide reached 14.6%. Furthermore, the designed nanotube array enzymatic reactor could be also used in situ to monitor the tolbutamide concentration with sensitivity of 28.8 ?A mM(-1) and detection limit of 0.52 ?M. Therefore, the proposed nanotube array enzymatic reactor was a good vessel for studying enzyme biocatalysis and drug metabolism, and has potential applications including efficient biosensors and bioreactors for chemical synthesis.
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[Outcomes and prognostic factors of advanced squamous cervical cancer after concurrent chemoradiotherapy].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 07-18-2014
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To evaluate the outcomes and the prognostic factors for advanced squamous cervical cancer after concurrent chemoradiotherapy (CCRT).
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[Rice endogenous nitrogen fixing and growth promoting bacterium Herbaspirillum seropedicae DX35].
Wei Sheng Wu Xue Bao
PUBLISHED: 07-03-2014
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To screen efficient nitrogen fixation endophytes from rice and to analyze their growth-promoting properties.
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Black tea consumption and serum cholesterol concentration: Systematic review and meta-analysis of randomized controlled trials.
Clin Nutr
PUBLISHED: 06-06-2014
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The results of randomized controlled trials in relation to the effect of regular black tea consumption on serum cholesterol concentration were inconsistent. We aimed to investigate and quantify the effect of black tea consumption on serum concentrations of total, LDL and HDL cholesterol.
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Target-cell-specific fluorescence silica nanoprobes for imaging and theranostics of cancer cells.
Anal. Chem.
PUBLISHED: 03-13-2014
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MicroRNAs (miRNAs) has been identified as diagnostic and prognostic biomarkers and predictors of drug response for many diseases, including a broad range of cancers, heart disease, and neurological diseases. The noninvasive theranostics system for miRNAs is very important for diagnosis and therapy of the cellular disease. Herein, a target-cell-specific theranostics nanoprobe for target-cell-specific delivery, cancer cells and intracellular miRNA-21 imaging, and cancer cell growth inhibition was proposed. The nanoprobe (FS-AS/MB) was prepared by simultaneously coupling of the AS1411 aptamer and miRNA-21 molecular beacon (miR-21-MB) onto the surface of Ru(bpy)?²?-encapsulated silica (FS) nanoparticles. The FS nanoparticles synthesized by a facile reverse microemulsion method showed nearly monodisperse spherical shape with a smooth surface, good colloidal stability, a fluorescence quantum yield of ~21%, and low cytotoxicity. The antibiofouling polymer PEG grafted onto a silica shell reduced nonspecific uptake of cells. The ability of FS-AS/MB for target-specific cells delivery, simultaneous cancer cells, intracellular miRNA-21 imaging, and inhibition of miRNA-21 function and suppression of cell growth in vitro, were also demonstrated. The results of the present study suggested that the proposed nanoprobes would be a promising theranostics for different cancers by imaging and inhibiting other intracellular genes.
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Noise model based ?-support vector regression with its application to short-term wind speed forecasting.
Neural Netw
PUBLISHED: 03-09-2014
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Support vector regression (SVR) techniques are aimed at discovering a linear or nonlinear structure hidden in sample data. Most existing regression techniques take the assumption that the error distribution is Gaussian. However, it was observed that the noise in some real-world applications, such as wind power forecasting and direction of the arrival estimation problem, does not satisfy Gaussian distribution, but a beta distribution, Laplacian distribution, or other models. In these cases the current regression techniques are not optimal. According to the Bayesian approach, we derive a general loss function and develop a technique of the uniform model of ?-support vector regression for the general noise model (N-SVR). The Augmented Lagrange Multiplier method is introduced to solve N-SVR. Numerical experiments on artificial data sets, UCI data and short-term wind speed prediction are conducted. The results show the effectiveness of the proposed technique.
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A phase II study of concurrent chemo-radiotherapy with weekly nedaplatin in advanced squamous cell carcinoma of the uterine cervix.
Radiat Oncol
PUBLISHED: 02-14-2014
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To evaluate the efficacy and safety of concurrent chemo-radiotherapy with weekly nedaplatin for the treatment of advanced squamous cell carcinoma of the uterine cervix.
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[Association of HLA-DQA1 gene rs9272346 polymorphism with clinical outcome of hepatitis B virus infection in ethnic Han population from Hubei].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 02-11-2014
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To assess the association of rs9272346 polymorphism of HLA-DQA1 gene with clinical outcome of hepatitis B virus (HBV) infection in ethnic Han population from Hubei, China.
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Anti-inflammatory activity and mechanism of a lipid extract from hard-shelled mussel (Mytilus coruscus) on chronic arthritis in rats.
Mar Drugs
PUBLISHED: 01-13-2014
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The present study was designed to investigate the anti-inflammatory activity and mechanism of a lipid extract from hard-shelled mussel (Mytilus coruscus) on adjuvant-induced (AIA) and collagen-induced arthritis (CIA) in rats. AIA and CIA rats that received hard-shelled mussel lipid extract (HMLE group) at a dose of 100 mg/kg demonstrated significantly lower paw swelling and arthritic index, but higher body weight gain than those which received olive oil (control group). Similar results were found in arthritic rats that received New Zealand green-lipped mussel lipid extract (GMLE) at the same dosage. The levels of leukotriene B? (LTB?), prostaglandin E? (PGE?), thromboxane B? (TXB?) in the serum, and interleukin-1? (IL-1?), IL-6, interferon-? (INF-?), tumor necrosis factor-? (TNF-?) in the ankle joint synovial fluids of HMLE group rats were significantly lower than those of control group. However, the levels of IL-4 and IL-10 in HMLE group rats were significantly higher than those in the control group. Decreased mRNA expressions of matrix metalloproteinase 1 (MMP1) and MMP13, but increased tissue inhibitor of metalloproteinase 1 (TIMP1) were observed in the knee joint synovium tissues of HMLE group rats when compared with the control group. No hepatotoxicity was observed in both HMLE and GMLE group rats. The present results indicated that HMLE had a similarly strong anti-inflammatory activity as GMLE. Such a strong efficacy could result from the suppression of inflammatory mediators (LTB?, PGE?, TXB?), pro-inflammatory cytokines (IL-1?, IL-6, INF-?, TNF-?) and MMPs (MMP1, MMP13), and the promotion of anti-inflammatory cytokines (IL-4, IL-10) and TIMPs (TIMP1) productions.
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Effect of marine-derived n-3 polyunsaturated fatty acids on C-reactive protein, interleukin 6 and tumor necrosis factor ?: a meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Previous studies did not draw a consistent conclusion about the effects of marine-derived n-3 polyunsaturated fatty acids (PUFAs) on fasting blood level of C-reactive protein (CRP), interleukin 6 (IL-6) and tumor necrosis factor ? (TNF-?).
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Cylindrical rotating triboelectric nanogenerator.
ACS Nano
PUBLISHED: 06-25-2013
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We demonstrate a cylindrical rotating triboelectric nanogenerator (TENG) based on sliding electrification for harvesting mechanical energy from rotational motion. The rotating TENG is based on a core-shell structure that is made of distinctly different triboelectric materials with alternative strip structures on the surface. The charge transfer is strengthened with the formation of polymer nanoparticles on surfaces. During coaxial rotation, a contact-induced electrification and the relative sliding between the contact surfaces of the core and the shell result in an "in-plane" lateral polarization, which drives the flow of electrons in the external load. A power density of 36.9 W/m(2) (short-circuit current of 90 ?A and open-circuit voltage of 410 V) has been achieved by a rotating TENG with 8 strip units at a linear rotational velocity of 1.33 m/s (a rotation rate of 1000 r/min). The output can be further enhanced by integrating more strip units and/or applying larger linear rotational velocity. This rotating TENG can be used as a direct power source to drive small electronics, such as LED bulbs. This study proves the possibility to harvest mechanical energy by TENGs from rotational motion, demonstrating its potential for harvesting the flow energy of air or water for applications such as self-powered environmental sensors and wildlife tracking devices.
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Visualizing hepatitis B virus with biarsenical labelling in living cells.
Liver Int.
PUBLISHED: 06-12-2013
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Study on viruses has greatly benefited from visualization of viruses tagged with green fluorescent protein (GFP) in living cells. But GFP tag, as a large inserted fragment, is not suitable for labelling Hepatitis B virus (HBV) that is a compact virion with limited internal space.
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[Diversity of endophytic bacteria in rice seeds and their secretion of indole acetic acid].
Wei Sheng Wu Xue Bao
PUBLISHED: 05-18-2013
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This study aimed to investigate the diversity of endophytic bacteria isolated from rice seeds, and screen indole acetic acid secrecting srtains.
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Integrated multilayered triboelectric nanogenerator for harvesting biomechanical energy from human motions.
ACS Nano
PUBLISHED: 03-18-2013
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We demonstrate a new flexible multilayered triboelectric nanogenerator (TENG) with extremely low cost, simple structure, small size (3.8 cm×3.8 cm×0.95 cm) and lightweight (7 g) by innovatively integrating five layers of units on a single flexible substrate. Owing to the unique structure and nanopore-based surface modification on the metal surface, the instantaneous short-circuit current (Isc) and the open-circuit voltage (Voc) could reach 0.66 mA and 215 V with an instantaneous maximum power density of 9.8 mW/cm2 and 10.24 mW/cm3. This is the first 3D integrated TENG for enhancing the output power. Triggered by press from normal walking, the TENG attached onto a shoe pad was able to instantaneously drive multiple commercial LED bulbs. With the flexible structure, the TENG can be further integrated into clothes or even attached onto human body without introducing sensible obstruction and discomfort to human motions. The novel design of TENG demonstrated here can be applied to potentially achieve self-powered portable electronics.
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Flow injection chemiluminescence immunoassay of microcystin-LR by using PEI-modified magnetic beads as capturer and HRP-functionalized silica nanoparticles as signal amplifier.
Analyst
PUBLISHED: 01-19-2013
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A rapid sandwiched immunoassay of microcystin-LR (MC-LR) in water is proposed with flow injection chemiluminescence detection. The magnetic beads (MBs) were first modified with polyethyleneimine (PEI) by acylamide bond between the carboxyl group on the surface of MBs and the primary amine group in PEI, followed by immobilizing of anti-MC-LR (Ab1) onto PEI with glutaraldehyde as linkage. The resulting Ab1 modified MBs captured the target MC-LR in water, reacted with the horseradish peroxidase and anti-MC-LR co-immobilized silica nanoparticles, and were detected with flow injection chemiluminescence. When using PEI/MBs as the carrier of anti-MC-LR, the CL signal was greatly enhanced up to 9-fold compared to that using MBs without PEI modification. The CL signal was further amplified 13-fold when Si/Ab2 was used as the signal probe. Under the optimal conditions, the present immunoassay exhibited a wide quantitative range from 0.02 to 200 ?g L(-1) with a detection limit of 0.006 ?g L(-1), which was much lower than the WHO provisional guideline limit of 1.0 ?g L(-1) for MC-LR in drinking water. The relative standard deviation was 4.8% and the recoveries for the spiked samples ranged from 84% to 115%, which indicated acceptable precision and accuracy for MC-LR. The present method is easier to perform and less time-consuming (the entire analysis process lasted about 40 minutes) and has been applied to the detection of MC-LR in different water samples successfully.
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Association of a single-nucleotide polymorphism within the miR-146a gene with susceptibility for acute-on-chronic hepatitis B liver failure.
Immunogenetics
PUBLISHED: 01-06-2013
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Excessive activation of innate immune response contributes to the pathogenesis of acute-on-chronic hepatitis B liver failure (ACLF-HBV). miR-146a was recently found to be implicated in the regulation of innate immunity. In this study, we explored the biological significance of a single-nucleotide polymorphism (rs2910164) within the miR-146a gene in the risk of acquiring ACLF-HBV. We completed a hospital-based case-control study including 717 cases of HBV-infected patients--251 cases of ACLF-HBV and 466 cases of chronic hepatitis B. Whole blood samples were collected for isolation of DNA and peripheral blood mononuclear cells (PBMCs). The association between genotypes and risk of ACLF-HBV was analyzed by multivariate unconditional logistic regression, with adjustment for sex and age. Our results showed that the GG homozygote was a protective genotype in terms of susceptibility to ACLF-HBV, with odds ratio?=?0.496, 95 % confidence interval?=?0.309-0.797, P?=?0.004 compared with CC+GC genotypes. The amount of mature miR-146a in PBMCs was significantly higher in the GG homozygote group than those in the CC and CG genotype groups of ACLF-HBV patients. The GG genotype group also represented lower serum level of TNF-? and higher survival rate (follow-up period?=?4 months). In conclusion, The GG genotype within the pre-miR-146a is reversely associated with susceptibility of ACLF-HBV in the studied Chinese population. This may be partially explained by the relatively higher amount of mature miR-146a and the lower serum level of TNF-? in this genotype group.
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A genome-wide association study with DNA pooling identifies the variant rs11866328 in the GRIN2A gene that affects disease progression of chronic HBV infection.
Viral Immunol.
PUBLISHED: 10-19-2011
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Host genetics play a vital role in determining clinical outcomes of hepatitis B virus (HBV) infection. To identify novel susceptibility loci to HBV progression, we carried out a genome-wide association study with DNA pooling. This study assessed the relationship between 8 highly-ranked SNPs selected from our DNA pool and disease progression of HBV infection in two independent case-control studies. The first population included 628 asymptomatic HBV carriers (AsC) and 1729 progressed HBV carriers recruited from Hubei Province in south China. The second population was composed of 226 AsC and 215 progressed HBV carriers recruited from Shandong Province in north China. Of the 8 SNPs, variant rs11866328 (G/T), located in the glutamate receptor ionotropic N-methyl D-aspartate 2A (GRIN2A) gene, was replicated and had significant associations with disease progression of HBV infection in the DNA pooling stage both in the Hubei (OR 1.65; 95% CI 1.34,2.02; p=1.96 × 10(-6); additive model), and in the Shandong (OR 1.73; 95% CI 1.14,2.65; p=1.00×10(-2); additive model) population. Polymorphism rs11866328 in the GRIN2A gene might be a genetic variant underlying the susceptibility of HBV carriers to disease progression.
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Fish consumption and CHD mortality: an updated meta-analysis of seventeen cohort studies.
Public Health Nutr
PUBLISHED: 09-14-2011
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Results of studies on fish consumption and CHD mortality are inconsistent. The present updated meta-analysis was conducted to investigate the up-to-date pooling effects.
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Green tea and black tea consumption and prostate cancer risk: an exploratory meta-analysis of observational studies.
Nutr Cancer
PUBLISHED: 06-11-2011
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Observational studies on tea consumption and prostate cancer (PCa) risk are still inconsistent. The authors conducted a meta-analysis to investigate the association between green tea and black tea consumption with PCa risk. Thirteen studies providing data on green tea or black tea consumption were identified by searching PubMed and ISI Web of Science databases and secondary referencing qualified for inclusion. A random-effects model was used to calculate the summary odds ratios (OR) and their corresponding 95% confidence intervals (CIs). For green tea, the summary OR of PCa indicated a borderline significant association in Asian populations for highest green tea consumption vs. non/lowest (OR = 0.62; 95% CI: 0.38-1.01); and the pooled estimate reached statistically significant level for case-control studies (OR = 0.43; 95% CI: 0.25-0.73), but not for prospective cohort studies (OR = 1.00; 95% CI: 0.66-1.53). For black tea, no statistically significant association was observed for the highest vs. non/lowest black tea consumption (OR = 0.99; 95% CI: 0.82-1.20). In conclusion, this meta-analysis supported that green tea but not black tea may have a protective effect on PCa, especially in Asian populations. Further research regarding green tea consumption across different regions apart from Asia is needed.
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High consumption of ?-3 polyunsaturated fatty acids decrease plasma homocysteine: a meta-analysis of randomized, placebo-controlled trials.
Nutrition
PUBLISHED: 04-17-2011
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High consumption of ?-3 polyunsaturated fatty acids (PUFAs) has been associated with lower plasma homocystine (Hcy) levels, but intervention studies in humans have been inconclusive. The objective was to systematically evaluate the effects of ?-3 PUFA supplementation on plasma Hcy levels.
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Effects of variant rs346473 in ARHGAP24 gene on disease progression of HBV infection in Han Chinese population.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 02-17-2011
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Host genetic, environmental and viral factors are classified as three categories that determine clinical outcomes of hepatitis B virus (HBV) infection. The objective of this study was to detect the associations between polymorphisms rs346473 and rs346482 in Rho GTPase-activating protein 24 (ARHGAP24) gene and disease progression of HBV infection in Han Chinese population. These two SNPs were found by our DNA pooling using Affymetrix Genome-Wide Human Mapping SNP6.0 Array in HBV carriers, and verified by using TaqMan 7900HT Sequence Detection System with 758 progressed HBV carriers versus 300 asymptomatic HBV carriers (AsC) in a discovery phase and 971 progressed HBV carriers versus 328 AsC in a replication phase. Multivariable logistic regression revealed that individuals with genotype TT at variant rs346473 displayed remarkable correlations with disease progression of HBV infection both in the discovery phase (OR, 2.693; 95% CI, 1.928-3.760; P=6.2×10(-9); additive model) and the replication phase (OR, 1.490; 95% CI, 1.104-2.012; P=9.0×10(-3); additive model). These two SNPs were in strong linkage disequilibrium with D=0.99 and r (2)=0.951, and haplotype TT disclosed an increased susceptibility to HBV progression (OR, 1.980; 95% CI, 1.538-2.545; P=8.1×10(-8)). These findings suggest that polymorphism rs346473 in the ARHGAP24 gene might be a part of the genetic variants underlying the susceptibility of HBV carriers to disease progression.
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Associations of HLA-DP variants with hepatitis B virus infection in southern and northern Han Chinese populations: a multicenter case-control study.
PLoS ONE
PUBLISHED: 01-27-2011
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Human leukocyte antigen DP (HLA-DP) locus has been reported to be associated with hepatitis B virus (HBV) infection in populations of Japan and Thailand. We aimed to examine whether the association can be replicated in Han Chinese populations.
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MCM3AP, a novel HBV integration site in hepatocellular carcinoma and its implication in hepatocarcinogenesis.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 08-17-2010
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A novel HBV integration site involved in hepatocarcinogenesis was investigated. The HBV DNA integration sites were detected by Alu-PCR in hepatocellular carcinoma tissues, matched surrounding liver tissues in 30 patients with hepatitis B-related hepatocellular carcinoma (HCC) and 3 cases of normal liver tissues. The integration sites and flanking sequences in human genome were sequenced and blasted, and the expression of integrated HBV genes was determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The influence of the up-regulated expression of integrated genes on hepatocarcinogenesis was analyzed. Nineteen integration sites of HBV DNA into HCC tissues were obtained by RT-PCR and sequencing. These genes encoding proteins were: LOC51030, LOC157777, minichromosome maintenance complex component 3 associated protein (MCM3AP), MCTP1, SH3 and multiple ankyrin repeat domains 2 isoform 2, CCDC40, similar to HCG2033532, mitochondrial ribosomal S5 pseudogene 4. One of them was integrated into the intron of MCM3AP. RT-PCR demonstrated that the expression levels of MCM3AP mRNA in HCC tissues, matched surrounding liver tissues and normal liver tissues were in a descendent order. The ratio of MCM3AP mRNA to the GAPDH mRNA in these three tissues was 1.07375, 0.21573, 0.06747 respectively, with the difference being statistically significant among them (P<0.05). Meanwhile, the expression levels of MCM3AP mRNA from HCC tissues in which HBV DNA integrated into MCM3AP were still significantly higher than those without HBV DNA integrated into MCM3AP. It was concluded that the HBV DNA integration sites into human genome were random, and MCM3AP was a new site. The up-regulated MCM3AP mRNA may affect flanking sequences which promote the hepatocarcinogenesis.
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Microemulsion extraction separation and determination of aluminium species by spectrofluorimetry.
J. Hazard. Mater.
PUBLISHED: 06-15-2010
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A simple and sensitive microemulsion extraction separation method was developed for the speciation of aluminium in tea samples by spectrofluorimetry. With 8-hydroxyquinoline (8-HQ) as the chelating agent and Triton X-100 Winsor II microemulsion as the extractant, separation of aluminium species in different pH solutions was achieved by microemulsion extraction. The formation of microemulsion, the conditions of extraction and determination of aluminium species were studied. The results showed that, the contents of aluminium species in tea leaves and infusions samples, such as total aluminium, total soluble aluminium, total granular aluminium, inorganic aluminium except Al-F, and (Al-F+Al-org), were obtained successfully under the optimal conditions. The limit of detection was 0.23 ?g L(-1) in pH 9.5 solution, and 0.59 ?g L(-1) in pH 6.0 solution respectively; the precision (RSD) for 11 replicate measurements of 10 ?g L(-1) aluminium was 2.1% in pH 9.5 solution, and 2.8% in pH 6.0 solution respectively; the recoveries for the spiked samples were 96.8-103.5%. The proposed method is simple and efficient, which has been applied to the speciation of aluminium in tea samples with satisfactory results.
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DNA double-strand breaks, potential targets for HBV integration.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 01-04-2010
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Hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC) is one of the most frequently occurring cancers. Hepadnaviral DNA integrations are considered to be essential agents which can promote the process of the hepatocarcinogenesis. More and more researches were designed to find the relationship of the two. In this study, we investigated whether HBV DNA integration occurred at sites of DNA double-strand breaks (DSBs), one of the most detrimental DNA damage. An 18-bp I-SceI homing endonuclease recognition site was introduced into the DNA of HepG2 cell line by stable DNA transfection, then cells were incubated in patients serum with high HBV DNA copies and at the same time, DSBs were induced by transient expression of I-SceI after transfection of an I-SceI expression vector. By using nest PCR, the viral DNA was detected at the sites of the break. It appeared that integration occurred between part of HBVxgene and the I-SceI induced breaks. The results suggested that DSBs, as the DNA damages, may serve as potential targets for hepadnaviral DNA insertion and the integrants would lead to widespread host genome changes necessarily. It provided a new site to investigate the integration.
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Suppressive effects of genomic imprinted gene PEG10 on hydrogen peroxide-induced apoptosis in L02 cells.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 12-29-2009
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The effects of PEG10 on hydrogen peroxide (H2O2)-induced apoptosis in human normal liver cell line L02 were investigated. The PEG10 gene was transfected into L02 cells by lipofectamine, the positive clone was screened by G418 and defined as L02/PEG10, while the cell transfected with empty expression vector (pEGFP-N1) was defined as L02/vector. L02/vector and parental L02 cells served as control. RT-PCR and Western blotting were employed to detect the expression of target genes. H2O2 (50-400 mmol/L) was administered to induce the apoptosis of L02 cells. Cells viability was measured by MTT and the morphological changes of apoptotic cells were determined by fluorescence microscopy using hoechst33342 nuclei staining. DNA fragmentation was observed by agarose gel electrophoresis. PEG10 mRNA and protein levels in L02/PEG10 cells were significantly increased as compared with those in the control cells. After treatment with 400 mmol/L H2O2 for 24 h, the cellular growth inhibition rate of L02/PEG10 cells was significantly lower (58.2%) than that of L02 (92.5%) and L02/vector (88%). Distinct morphological changes characteristic of cell apoptosis such as karyopyknosis and conglomeration were not observed in L02/PEG10. Ladder-like DNA fragmentation in a dose-dependent manner was observed in both L02 and L02/vector cell lines, but not in L02/PEG10. PEG10 over-expression significantly inhibited cytotoxicity induced by H2O2 on human normal liver cell line L02 by antagonizing H2O2-induced apoptosis.
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Primary malignant amelanotic melanoma of the female genital tract: report of two cases and review of literature.
Melanoma Res.
PUBLISHED: 06-16-2009
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Primary amelanotic melanoma of the female genital tract usually has a poor outcome as a consequence of delayed diagnosis and lack of standardized treatment. We report two cases of this disease originating in the vulva and uterine cervix, respectively. The related literature is reviewed. Compared with amelanotic melanoma of the female genital tract of the vulva, disease of the cervix is more likely to be misdiagnosed, identified at a later stage, and have a poorer outcome.
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Inhibition of miR-96 expression reduces cell proliferation and clonogenicity of HepG2 hepatoma cells.
Oncol. Rep.
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microRNAs (miRNAs) are negative regulators of gene expression and can function as tumor suppressors or oncogenes. Several miRNAs are associated with the development of hepatocellular carcinoma (HCC). miR-96 has been closely associated with cell proliferation and clonogenicity. Upregulation of miR-96 has been observed in various types of cancer. However, the biological function of miR-96 in hepatocarcinogenesis remains largely unknown. In this study, we demonstrated that miR-96 was upregulated in HCC and inhibition of miR-96 significantly suppressed HCC cell proliferation and colony formation. The expression levels of forkhead box O1 (FOXO1) and forkhead box O3a (FOXO3a) were upregulated when miR-96 was inhibited in HCC cells and the inhibition of FOXO1 and FOXO3a promoted HCC cell proliferation and colony formation. Collectively, these data reveal an important contribution of miR-96 to hepatocarcinogenesis and suggest a role for FOXO1 and FOXO3a dysregulation in this process. Thus, the use of a synthetic inhibitor of miR-96 may be a promising approach for the treatment of HCC.
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Manipulation of autophagy by MIR375 generates antitumor effects in liver cancer.
Autophagy
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The exploration into the roles of autophagy in tumorigenesis, either as tumor suppressor or tumor promoter, has led to a great increase in the knowledge of cancer development, progression and treatment. However, there is currently no consensus on how to manipulate autophagy to improve antitumor effects. In this study, we investigated the role of autophagy in established liver cancer cells in response to hypoxia. Hypoxia not only is the most pervasive microenvironmental stress in solid tumors but is also a canonical stimulus for autophagy. The involvement of dysregulated microRNAs in hypoxia-induced autophagy and their therapeutic potential in advanced liver cancer were examined.
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Cardiovascular disease mortality and cancer incidence in vegetarians: a meta-analysis and systematic review.
Ann. Nutr. Metab.
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Prospective cohort studies have examined mortality and overall cancer incidence among vegetarians, but the results have been inconclusive.
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?-2 spectrin is involved in hepatocyte proliferation through the interaction of TGF?/Smad and PI3K/AKT signalling.
Liver Int.
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Transforming growth factor (TGF) ? signalling pathway plays a crucial role in liver regeneration following partial hepatectomy in mice. Evidence demonstrated that ?-2 Spectrin is involved in TGF?/Smad signalling pathway as a Smad3/4 adaptor protein.
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miR-375 inhibits autophagy and reduces viability of hepatocellular carcinoma cells under hypoxic conditions.
Gastroenterology
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Tumor cells survive hypoxic conditions by inducing autophagy. We investigated the roles of microRNAs (miRNAs) in regulating autophagy of hepatocellular carcinoma (HCC) cells under hypoxic conditions.
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Serum levels of polyunsaturated fatty acids are low in Chinese men with metabolic syndrome, whereas serum levels of saturated fatty acids, zinc, and magnesium are high.
Nutr Res
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The purpose of this study was to examine the hypothesis that serum levels of phospholipid (PL) fatty acids (FA) and minerals are associated with the components of metabolic syndrome (MetS) in the Chinese population and the profiles of changes may differ from patients with MetS from Western countries. The levels of serum PL, FA, and minerals were examined in 201 subjects (52 with MetS and 149 healthy controls without any MetS components) in China. The saturated FA proportion in serum was significantly higher, whereas the proportion of total polyunsaturated FA (PUFA), n-3 and n-6 PUFA (22:6n-3: -16%, P = .006; 20:4n-6: -36%, P < .001), and estimated ?-5 desaturase were significantly lower in the MetS group compared with those that are not MetS. Subjects with MetS had higher levels of serum Zn (P = .037) and Mg (P < .001) than subjects without MetS. The proportion of n-3 PUFA was significantly negatively correlated with body mass index and waist circumference. In conclusion, serum PL FA composition and serum minerals in Chinese men with MetS differed significantly from that of healthy individuals, reflecting a decrease in n-3 and n-6 PUFA, especially 22:6n-3 and 20:4n-6, and an increase in saturated FA, magnesium, and zinc. These changes may reflect improper dietary intake in subjects with MetS, and dietary modification could be useful to prevent MetS and as an adjunctive therapy.
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Ganoderma lucidum polysaccharides exert anti-hyperglycemic effect on streptozotocin-induced diabetic rats through affecting ?-cells.
Comb. Chem. High Throughput Screen.
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Previous studies have demonstrated that Ganoderma lucidum polysaccharides (Gl-PS) exhibited potential antihyperglycemic effect in rats. The aim of the present study was to investigate the mechanism of the hypoglycemic effect of a low- molecular-weight Gl-PS in streptozotocin (STZ)-induced diabetic Sprague-Dawley (SD) rats. Gl-PS was extracted and purified from Ganodema lucidum fruiting body. 50 male SD rats were included in the study; 10 were taken as healthy controls; 40 were induced to diabetes by a single injection of 65 mg/kg STZ, of which 30 were selected as successful diabetic rat models. The 30 diabetic rats were divided into three groups: Gl-PS (200 mg/kg Gl-PS), metformin (100 mg/kg metformin) and diabetic control (n = 10 per group). After eight weeks oral administration, plasma concentrations of fasting glucose, triacylglyceride, total cholesterol and nitric oxide were significantly decreased in Gl-PS and metformin groups. Pancreatic superoxide dismutase, catalase and glutathione peroxidase were significantly increased in Gl-PS and metformin groups. Histopathological results showed that Gl-PS and metformin had protective effect on ?-cells. The mRNA expressions of Bcl-2 and PDX-1 in pancreas were up-regulated, but Bax, iNOS and Casp-3 down-regulated in Gl- PS and metformin groups compared to diabetic control group. The present results suggested that Gl-PS had a hypoglycemic effect in STZ-induced diabetic rats through preventing apoptosis of pancreatic ?-cells and enhancing ?-cells regeneration.
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