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Find video protocols related to scientific articles indexed in Pubmed.
Linear and nonlinear optical properties of terbium calcium oxyborate single crystals.
Opt Express
PUBLISHED: 11-18-2014
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The linear and nonlinear optical properties of TbCa4O(BO3)3 (abbreviated as TbCOB) single crystals were investigated for the first time. The refractive indices of TbCOB at several wavelengths were measured by using the minimum deviation method and the parameters of Sellmeier's dispersion equation were determined from the experimental data. The complete set of six second-order nonlinear optical (NLO) coefficients of TbCOB single crystals were obtained using the Maker fringe (FM) technique, with the largest d32 being on the order of 1.65 pm/V. Moreover, the phase-matching (PM) configurations of second-order harmonic generation (SHG) in the principal planes were calculated, and the largest effective NLO coefficient is deff = 0.86 pm/V along (22.56°, 180°) PM direction. The SHG conversion efficiency from 1064 nm to 532 nm of 8 mm long crystal samples without AR coating along this direction was achieved 57.1% at 28.2 mW input power, and it has a small walk-off angle of 13.8 mrad. In addition, the comparison and discussion with GdCOB and YCOB were carried out.
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Graphene oxide amplified fluorescence anisotropy for label-free detection of potassium ion.
Analyst
PUBLISHED: 11-07-2014
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Fluorescence anisotropy (FA) has attracted considerable attention, but it has been rarely applied for the detection of small molecules and metal ions because they are too small to induce evident FA changes. Although some mass amplifying strategies have been developed, the recognition probes need to be covalently modified with the fluorescent dyes, which is complex and expensive. To overcome this limitation, a new simple, label-free and cost-effective method for the sensitive detection of potassium ion (K(+)), by using graphene oxide (GO) as FA enhancer, a G-rich single stranded DNA (ssDNA) as recognition probe and acridine orange (AO) as FA reporting fluorophore, was established in this paper. In the absence of K(+), both ssDNA and AO are adsorbed on the surface of GO, and the FA of AO is enhanced greatly because the rotation of AO is coupled with the entire formation. After the addition of K(+), the ssDNA self-associates into the G-quadruplex structure. Then, AO can bind with the formed G-quadruplex strongly, keeping away from the surface of GO, and the FA of AO decreases significantly because of the relatively small size of the complex of AO and G-quadruplex. Thus K(+) can be detected sensitively in the range of 10 ?M-2 mM based on the evidently decreased FA. This method is a further improvement of the previous reported mass amplifying strategies because it does not require any covalent labelling of the recognition probe, and it can be potentially applied for detection of a variety of other targets.
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In situ labelling chemistry of respiratory syncytial viruses by employing the biotinylated host-cell membrane protein for tracking the early stage of virus entry.
Chem. Commun. (Camb.)
PUBLISHED: 11-06-2014
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An in situ labelling strategy was proposed to produce quantum dot-labelled respiratory syncytial viruses (RSVs) by incorporating the biotinylated membrane protein of the host cells into mature virions, followed by conjugation with streptavidin modified quantum dots (SA-QDs), which has the advantages such as convenience, efficiency and minor influence on viral infectivity and thus could be successfully applied to track the early stage of virus entry.
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Evaluation of the Therapeutic and Diagnostic Effects of PEGylated Liposome-Embedded 188Re on Human Non-Small Cell Lung Cancer Using an Orthotopic Small-Animal Model.
J. Nucl. Med.
PUBLISHED: 10-27-2014
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Non-small cell lung cancer (NSCLC) is a highly morbid and mortal cancer type that is difficult to eradicate using conventional chemotherapy and radiotherapy. Little is known about whether radionuclide-based pharmaceuticals can be used for treating NSCLC. Here we embedded the therapeutic radionuclide (188)Re in PEGylated (PEG is polyethylene glycol) liposomes and investigated the biodistribution, pharmacokinetics, and therapeutic efficacy of this nanoradiopharmaceutical on NSCLC using a xenograft lung tumor model and the reporter gene imaging techniques.
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Electroacupuncture at Feishu (BL13) and Zusanli (ST36) down-regulates the expression of orexins and their receptors in rats with chronic obstructive pulmonary disease.
J Integr Med
PUBLISHED: 10-09-2014
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Inflammation and lung function decline are the main pathophysiological features of chronic obstructive pulmonary disease (COPD). Acupuncture can improve lung function in patients with COPD, but the underlying mechanisms are not well understood. Orexins (OXs), which are found in peripheral plasma, are neuropeptides that regulate respiration and their levels are related to COPD. Therefore, we hypothesized that acupuncture might alter OXs, reduce lung inflammation and improve lung function in COPD.
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[An automatic peak detection method for LIBS spectrum based on continuous wavelet transform].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-02-2014
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Spectrum peak detection in the laser-induced breakdown spectroscopy (LIBS) is an essential step, but the presence of background and noise seriously disturb the accuracy of peak position. The present paper proposed a method applied to automatic peak detection for LIBS spectrum in order to enhance the ability of overlapping peaks searching and adaptivity. We introduced the ridge peak detection method based on continuous wavelet transform to LIBS, and discussed the choice of the mother wavelet and optimized the scale factor and the shift factor. This method also improved the ridge peak detection method with a correcting ridge method. The experimental results show that compared with other peak detection methods (the direct comparison method, derivative method and ridge peak search method), our method had a significant advantage on the ability to distinguish overlapping peaks and the precision of peak detection, and could be be applied to data processing in LIBS.
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Risk factors for bunyavirus-associated severe Fever with thrombocytopenia syndrome, china.
PLoS Negl Trop Dis
PUBLISHED: 10-01-2014
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Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease that is caused by a novel bunyavirus, referred to as SFTS virus. During January 2011 to December 2011 we conducted a case-control study in Henan, Hubei and Shandong Provinces of China to determine the risk factors for SFTS.
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[Effect of Cu2+ on the power output of dual-chamber microbial fuel cell].
Huan Jing Ke Xue
PUBLISHED: 09-24-2014
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After addition of Cu2+ into the anodic and/or cathodic chamber, the effect of Cu2+ on the internal resistance and its distribution, power output and coulombic efficiency of dual-chamber microbial fuel cell (MFC) was investigated in this manuscript with the aid of analyzing the distribution of copper speciation. It could provide helpful information for correlative research on treatment of copper-containing wastewater by MFC. It showed that the addition of 10 mg x L(-1) Cu2+ into the anodic chamber inhibited the microbial activity, and increased the anodic activation resistance as well as the apparent internal resistance, consequently reduced the power output and coulombic efficiency of the system. However, the addition of 500 mg x L(-1) Cu2+ into the cathodic chamber significantly reduced the cathodic activation resistance as well as the apparent internal resistance, while improved the power output and the coulombic efficiency. Cu2+ in the anodic chamber was not transfered into the cathodic chamber. When adding Cu2+ into the cathodic chamber, it was mainly reduced and deposited on the cathodic chamber. It could also be transferred/diffused to the anodic chamber across the proton exchange membrane (2.8%) because of its concentration difference, thus affecting the microbial activity and power output. Only a small amount of Cu2+ remained in the supernatant of the cathodic chamber at the end of experiment.
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[Chemical constituents from Euphorbia lunulata].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-24-2014
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The chemical constituents from Euphorbia lunulata was investigated in this paper. Fourteen compounds were isolated and purified by column chromatographies on silica gel and preparative HPLC. Their structures were identified by physiochemical properties and NMR data analysis as lupeol (1), euphol (2), cassipourol(3) , 24-methylenecycloartan-3beta-ol (4), 24-hydroperoxycycloart-25-en-3beta-ol (5), 25-hydroperoxycycloart-23-en-3beta-ol (6), betulin (7), uvaol (8), (23E) -25-methoxycycloart-23-en-3beta-ol (9), (23E) -cycloart-23,25-dien-3beta-ol (10), 24-methylenecycloartan-3beta, 28-diol (11), salicinolide (12), 2alpha, 3beta, 5alpha, 9alpha, 15beta-pentaacetoxy-11,12-epoxy-7beta, 8alpha-diisobutyryloxyjatropha-6 (17) -en-14-one (13) and 3beta, 5alpha, 15beta-triacetoxy-7beta-isobutyryloxy-9alpha-nicotinoyloxyjatropha-6 (17), 11(E)-dien-14-one (14). Among them, compounds 1-11 were isolated from E. lunulata for the first time.
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Active sites and mechanisms for oxygen reduction reaction on nitrogen-doped carbon alloy catalysts: Stone-Wales defect and curvature effect.
J. Am. Chem. Soc.
PUBLISHED: 09-23-2014
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Carbon alloy catalysts (CACs) are promising oxygen reduction reaction (ORR) catalysts to substitute platinum. However, despite extensive studies on CACs, the reaction sites and mechanisms for ORR are still in controversy. Herein, we present rather general consideration on possible ORR mechanisms for various structures in nitrogen doped CACs based on the first-principles calculations. Our study indicates that only a particular structure of a nitrogen pair doped Stone-Wales defect provides a good active site. The ORR activity of this structure can be tuned by the curvature around the active site, which makes its limiting potential approaching the maximum limiting potential (0.80 V) in the volcano plot for the ORR activity of CACs. The calculated results can be compared with the recent experimental ones of the half-wave potential for CAC systems that range from 0.60 to 0.80 V in the reversible-hydrogen-electrode (RHE) scale.
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[Culture medium based on biogas slurry and breeding of oil chlorella].
Huan Jing Ke Xue
PUBLISHED: 08-28-2014
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The oil chlorella cultivation and biogas slurry treatment were combined. The biogas slurry provided water and nutrient for growing chlorella, at the same time, harmless treatment of biogas slurry was realized. This paper cultivated 4 species of oil chlorella in the mixed medium of biogas slurry and green algae medium (the volume ratios were 1 : 9, 1 : 3, 1 : 1 and 3 : 1, respectively), and compared their oil productivity to select the best oil chlorella species and the optimal culture medium. The results showed that, the combination of medium and chlorella species to reach the highest oil productivity was a volume ratio of 1 : 3 and the chlorella species BJ05, and the oil productivity of chlorella BJ05 was 9.20 mg x (L x d)(-1), higher than that in green algae medium [8.66 mg x (L x d)(-1)]. In mixed medium with a volume ratio of 1:3, the effect of adding different nutrients into the green algae medium on the oil productivity was examined, and the results showed that, sodium carbonate and citric acid had no negative effect on the oil productivity of chlorella BJ05. in the absence of sodium carbonate and citric acid, the oil productivity of chlorella BJ05 was 9.36 mg x (L x d)(-1), and the removal of COD (chemical oxygen demand), total nitrogen, total phosphorus and ammonia nitrogen rates were 59%, 75%, 61% and 100%, respectively. Deficiency in other nutrients had negative effect on the oil productivity. Therefore, the culture medium was further optimized to the mixed medium of biogas slurry and green algae medium with a volume ratio of 1 : 3 and without addition of sodium carbonate and citric acid.
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Schisandrin B induces apoptosis and cell cycle arrest of gallbladder cancer cells.
Molecules
PUBLISHED: 08-27-2014
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Gallbladder cancer, with high aggressivity and extremely poor prognosis, is the most common malignancy of the bile duct. The main objective of the paper was to investigate the effects of schisandrin B (Sch B) on gallbladder cancer cells and identify the mechanisms underlying its potential anticancer effects. We showed that Sch B inhibited the viability and proliferation of human gallbladder cancer cells in a dose-, time -dependent manner through MTT and colony formation assays, and decrease mitochondrial membrane potential (??m) at a dose-dependent manner through flow cytometry. Flow cytometry assays also revealed G0/G1 phase arrest and apoptosis in GBC-SD and NOZ cells. Western blot analysis of Sch B-treated cells revealed the upregulation of Bax, cleaved caspase-9, cleaved caspase-3, cleaved PARP and downregulation of Bcl-2, NF-?B, cyclin D1 and CDK-4. Moreover, this drug also inhibited the tumor growth in nude mice carrying subcutaneous NOZ tumor xenografts. These data demonstrated that Sch B induced apoptosis in gallbladder cancer cells by regulating apoptosis-related protein expression, and suggests that Sch B may be a promising drug for the treatment of gallbladder cancer.
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Novel band structures in silicene on monolayer zinc sulfide substrate.
J Phys Condens Matter
PUBLISHED: 08-27-2014
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Opening a sizable band gap in the zero-gap silicene without lowering the carrier mobility is a key issue for its application in nanoelectronics. Based on ?rst-principles calculations, we find that the interaction energies are in the range of -0.09?0.3?eV?per Si atom, indicating a weak interaction between silicene and ZnS monolayer and the ABZn stacking is the most stable pattern. The band gap of silicene can be effectively tuned ranging from 0.025 to 1.05?eV in silicene and ZnS heterobilayer (Si/ZnS HBL). An unexpected indirect-direct band gap crossover is also observed in HBLs, dependent on the stacking pattern, interlayer spacing and external strain effects on silicene. Interestingly, the characteristics of Dirac cone with a nearly linear band dispersion relation of silicene can be preserved in the ABS pattern which is a metastable state, accompanied by a small electron effective mass and thus the carrier mobility is expected not to degrade much. These provide a possible way to design effective FETs out of silicene on a ZnS monolayer.
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Self-assembled micellar nanocomplexes comprising green tea catechin derivatives and protein drugs for cancer therapy.
Nat Nanotechnol
PUBLISHED: 08-21-2014
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When designing drug carriers, the drug-to-carrier ratio is an important consideration, because the use of high quantities of carriers can result in toxicity as a consequence of poor metabolism and elimination of the carriers. However, these issues would be of less concern if both the drug and carrier had therapeutic effects. (-)-Epigallocatechin-3-O-gallate (EGCG), a major ingredient of green tea, has been shown, for example, to possess anticancer effects, anti-HIV effects, neuroprotective effects and DNA-protective effects. Here, we show that sequential self-assembly of the EGCG derivative with anticancer proteins leads to the formation of stable micellar nanocomplexes, which have greater anticancer effects in vitro and in vivo than the free protein. The micellar nanocomplex is obtained by complexation of oligomerized EGCG with the anticancer protein Herceptin to form the core, followed by complexation of poly(ethylene glycol)-EGCG to form the shell. When injected into mice, the Herceptin-loaded micellar nanocomplex demonstrates better tumour selectivity and growth reduction, as well as longer blood half-life, than free Herceptin.
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Global in vivo terminal amino acid labeling for exploring differential expressed proteins induced by dialyzed serum cultivation.
Analyst
PUBLISHED: 07-17-2014
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Taking advantage of reliable metabolic labeling and accurate isobaric MS2 quantification, we developed a global in vivo terminal amino acid labeling (G-IVTAL) strategy by combining metabolic labeling and isotopic dimethyl labeling for quantifying tryptic peptides. With G-IVTAL, the scale of qualitative and quantitative data can be increased twofold compared with in vivo termini amino acid labeling (IVTAL) in which Lys-N and Arg-C are used for digestion. As a result, up to 81.78% of the identified proteins have been confidently quantified in G-IVTAL-labeled HepG2 cells. Dialyzed serum has been used in most SILAC studies to ensure complete labeling. However, dialysis requires the removal of low molecular weight hormones, cytokines, and cellular growth factors, which are essential for the cell growth of certain cell lines. To address the influence of dialyzed serum in HepG2 growth, the G-IVTAL strategy was applied to quantify the expression differences between dialyzed serum- and normal serum-cultured HepG2 cells. Finally, we discovered 111 differentially expressed proteins, which could be used as references to improve the reliability of the SILAC quantification. Among these, by using western blotting, the differential expressions of MTDH, BCAP31, and GPC3 were confirmed as being influenced by dialyzed serum. The experimental results demonstrate that the G-IVTAL strategy is a powerful tool to achieve accurate and reliable protein quantification.
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[Glybenclamide regulate ERK1/2 signal pathway during hypoxia hypercapnia pulmonary vasoconstriction in rats].
Zhongguo Ying Yong Sheng Li Xue Za Zhi
PUBLISHED: 07-15-2014
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To investigate the role and significance of ATP-sensitive K+ channels in the pathological process of hypoxia hypercapnia-induced pulmonary vasoconstriction (HHPV) and the relationship with ERK1/2 signal pathway in rats.
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[Nutrient spatial variability of tobacco soil restoration area and fertility suitability level evaluation].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 07-03-2014
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By using geographic information system technology (GIS) and geostatistics methods, this paper studied the spatial variability of soil properties and available nutrients in the new regulation area units located in Qingjiangyuan modern tobacco agriculture science and technology park (Enshi, Hubei), suburb of Enshi City and the Baiyang base of Lichuan City, and further evaluation of the soil fertility suitability index (SFI) was carried out by use fuzzy mathematics. The results indicated that the effects of land restoration on the soil available phosphorus content variability and spatial distribution were very obvious, possibly due to the landform characteristics and restoration extent. The effect of land restoration on soil pH was small, however, serious soil acidification was detected in the soil sampled from Baiyang (pH < 5.5). Low SFI was found in 77.6%, 17.1% and 31.4% of the soils taken from the suburb, Baiyang and Qingjiangyuan, respectively. In conclusion, attentions should be paid on soil acidification in Baiyang, soil fertility and equalization in the suburb, and soil fertility in the region of Qingjiangyuan with low SFI.
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Peroxisome proliferator?activated receptor ? polymorphisms as risk factors for dyslipidemia.
Mol Med Rep
PUBLISHED: 06-26-2014
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Peroxisome proliferator?activated receptor ? (PPAR?) may play an important role in lipid metabolism directly or by inducing the transcription of target genes. The aim of the present study was to investigate the association between common variants at the PPAR? locus (C1431T and Pro12Ala polymorphisms) and lipid serum levels. The studied population consisted of 820 subjects randomly selected from the Prevention of Multiple Metabolic Disorders and Metabolic Syndrome in Jiangsu Province cohort population. All subjects were interviewed and blood samples were obtained for laboratory analysis and DNA extraction. The TaqMan single nucleotide polymorphism genotyping assay was used for polymorphism genotyping. Individual polymorphisms and haplotype data were available for analysis. The 12Ala allele was found to be associated with significantly increased levels of triglyceride (TG) (P<0.01), whilst the 1431T allele was found to be associated with significantly increased levels of TG, total cholesterol (TC) and non?high?density lipoprotein (non?HDL) (P<0.01). When P?C, the most common haplotype, was used as the reference group, the P?T, A?C and A?T haplotypes were found to be associated with significantly increased levels of TG (P<0.01). In addition, the A?T haplotype was shown to be associated with significantly increased levels of TC and non?HDL (P<0.01). In conclusion these results suggest that PPAR? gene variability may increase the risk of dyslipidemia.
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Tunable electronic and magnetic properties in germanene by alkali, alkaline-earth, group III and 3d transition metal atom adsorption.
Phys Chem Chem Phys
PUBLISHED: 06-26-2014
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We performed first-principles calculations to study the adsorption characteristics of alkali, alkali-earth, group III, and 3d transition-metal (TM) adatoms on germanene. We find that the adsorption of alkali or alkali-earth adatoms on germanene has minimal effects on geometry of germanene. The significant charge transfer from alkali adatoms to germanene leads to metallization of germanene, whereas alkali-earth adatom adsorption, whose interaction is a mixture of ionic and covalent, results in semiconducting behavior with an energy gap of 17-29 meV. For group III adatoms, they also bind germanene with mixed covalent and ionic bonding character. Adsorption characteristics of the transition metals (TMs) are rather complicated, though all TM adsorptions on germanene exhibit strong covalent bonding with germanene. The main contributions to the strong bonding are from the hybridization between the TM 3d and Ge pz orbitals. Depending on the induced-TM type, the adsorbed systems can exhibit metallic, half-metallic, or semiconducting behavior. Also, the variation trends of the dipole moment and work function with the adsorption energy across the different adatoms are discussed. These findings may provide a potential avenue to design new germanene-based devices in nanoelectronics.
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Cordycepin induces S phase arrest and apoptosis in human gallbladder cancer cells.
Molecules
PUBLISHED: 06-20-2014
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Gallbladder cancer is the most common malignant tumor of the biliary tract, and this condition has a rather dismal prognosis, with an extremely low five-year survival rate. To improve the outcome of unresectable and recurrent gallbladder cancer, it is necessary to develop new effective treatments and drugs. The purpose of the present study was to evaluate the effects of cordycepin on human gallbladder cells and uncover the molecular mechanisms responsible for these effects. The Cell Counting Kit-8 (CCK-8) and colony formation assays revealed that cordycepin affected the viability and proliferation of human gallbladder cancer cells in a dose- and time-dependent manner. Flow cytometric analysis showed that cordycepin induced S phase arrest in human gallbladder cancer cell lines(NOZ and GBC-SD cells). Cordycepin-induced apoptosis was observed using an Annexin V/propidium iodide (PI) double-staining assay, and the mitochondrial membrane potential (??m) decreased in a dose-dependent manner. Additionally, western blot analysis revealed the upregulation of cleaved-caspase-3, cleaved-caspase-9, cleaved-PARP and Bax and the downregulation of Bcl-2, cyclin A and Cdk-2 in cordycepin-treated cells. Moreover, cordycepin inhibited tumor growth in nude mice bearing NOZ tumors. Our results indicate that this drug may represent an effective treatment for gallbladder carcinoma.
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Effects of oxymatrine on the apoptosis and proliferation of gallbladder cancer cells.
Anticancer Drugs
PUBLISHED: 05-30-2014
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Gallbladder carcinoma is the most common malignancy of the biliary tract and is associated with a very poor outcome. The aim of the present study was to investigate the effects of oxymatrine (OM) on gallbladder cancer cells and the possible mechanism of its effects. The effects of OM on the proliferation of gallbladder cancer cells (GBC-SD and SGC-996) were investigated using cell counting kit-8 and colony formation assays. Annexin V/propidium iodide double staining was performed to investigate whether OM could induce apoptosis in gallbladder cancer cells. The mitochondrial membrane potential (??m) and expression of apoptosis-associated proteins were evaluated to identify a mechanism for the effects of OM. In addition, the RNA expression of relevant genes was measured by qRT-PCR using the SYBR Green method. Finally, a subcutaneous implantation model was used to verify the effects of OM on tumor growth in vivo. We found that OM inhibited the proliferation of gallbladder cancer cells. In addition, Annexin V/propidium iodide double staining showed that OM induced apoptosis after 48?h and the ??m decreased in a dose-dependent manner after OM treatment. Moreover, the activation of caspase-3 and Bax and downregulation of Bcl-2 and nuclear factor ?B were observed in OM-treated cells. Finally, OM potently inhibited in-vivo tumor growth following subcutaneous inoculation of SGC-996 cells in nude mice. In conclusion, OM treatment reduced proliferation and induced apoptosis in gallbladder cancer cells, which suggests that this drug may serve as a novel candidate for adjuvant treatment in patients with gallbladder cancer.
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Efficacy of gemcitabine combined with oxaliplatin, L-asparaginase and dexamethasone in patients with newly-diagnosed extranodal NK/T-cell lymphoma.
Mol Clin Oncol
PUBLISHED: 05-23-2014
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There is currently no standard first-line regimen for patients with extranodal natural killer (NK)/T-cell lymphoma (ENKTCL). In this study, we investigated the efficacy and toxicity of gemcitabine (GEM) combined with oxaliplatin (L-OHP), L-asparaginase (L-ASP) and dexamethasone (DXM) (GOLD regimen) as a systemic treatment scheme for newly-diagnosed ENKTCL cases. A total of 55 patients were recruited at the Henan Province Cancer Hospital and the Cancer Center of Sun Yat-sen University between May, 2008 and August, 2012. The GOLD regimen included a 14-day treatment cycle with GEM (1,000 mg/m(2)) on day 1, L-OHP (100 mg/m(2)) on day 1, L-ASP (10,000 U/m(2)) on days 1-5 and DXM (20 mg b.i.d.) on days 1-4. The response rate, survival rate and treatment toxicity were analyzed. The overall response rate was 91% (48/55) with a complete response in 62% (34/55) and a partial response in 29% (15/55) of the patients. For all patients, the 1-, 2- and 3-year progression-free survival (PFS) rate was 86, 64 and 57% and the overall survival (OS) 91, 80 and 74%, respectively. The 1-year PFS in patients with stage I/II vs. those with III/IV disease was 87 vs. 66% (P<0.001) and the 1-year OS was 98 vs. 75%, respectively (P<0.001). No chemotherapy-related mortality or severe complications were recorded. In conclusion, the GOLD regimen was found to be highly effective and safe for the treatment of patients with newly-diagnosed ENKTCL.
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Clinical and prognostic significance of preoperative plasma hyperfibrinogenemia in gallbladder cancer patients following surgical resection: a retrospective and in vitro study.
BMC Cancer
PUBLISHED: 05-12-2014
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Coagulation and fibrinolysis activation is frequently observed in cancer patients, and the tumors in these cases are thought to be associated with a higher risk of invasion, metastasis, and worse long-term outcome. The objective of this study was to elucidate the prognostic significance of blood coagulation tests and various clinicopathological characteristics in patients with gallbladder cancer (GBC) after surgical resection.
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Tissue levels of leukemia inhibitory factor vary by osteoarthritis grade.
Orthopedics
PUBLISHED: 05-10-2014
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The objective of this study was to observe the expression of leukemia inhibitory factor (LIF) in animals and in different clinical grades of patient osteoarthritic tissues. Thirty-five rabbits were used in a Colombo model of experimental osteoarthritis (OA). Five rabbits each were sacrificed on postoperative days 3, 7, 14, 28, 42, 56, and 84. Immunohistochemistry analysis for LIF expression and distribution in the cartilage and synovium of animals was performed at these times. Sixty-seven samples of human articular tissue were obtained from patients with different grades of OA according to symptoms and radiographic inspection. The mRNA expression of LIF was determined by reverse transcription polymerase chain reaction, and LIF protein was determined by enzyme-linked immunosorbent assay (ELISA). The results showed a slight expression of LIF in normal cartilage tissue but less in synovium tissue; however, the expression of LIF was marked in synovial lining cells and superficial and middle-layer cartilage in animal OA (P<.05). Leukemia inhibitory factor mRNA was expressed at the highest level in moderate degrading subchondral bone, and LIF was expressed at the highest level in seriously degrading articular cartilage tissue. These results were similar to those found with ELISA. This study suggests that LIF in OA articular tissues varies by clinical symptoms and grade. It plays an important role in the pathogenesis of OA.
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A proteomic analysis of rice seed germination as affected by high temperature and ABA treatment.
Physiol Plant
PUBLISHED: 05-04-2014
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Seed germination is a critical phase in the plant life cycle, but the specific events associated with seed germination are still not fully understood. In this study, we used two-dimensional gel electrophoresis followed by mass spectrometry to investigate the changes in the proteome during imbibition of Oryza sativa seeds at optimal temperature with or without abscisic acid (ABA) and high temperature (germination thermoinhibition) to further identify and quantify key proteins required for seed germination. A total of 121 protein spots showed a significant change in abundance (1.5-fold increase/decrease) during germination under all conditions. Among these proteins, we found seven proteins specifically associated with seed germination including glycosyl hydrolases family 38 protein, granule-bound starch synthase 1, Os03g0842900 (putative steroleosin-B), N-carbamoylputrescine amidase, spermidine synthase 1, tubulin ?-1 chain and glutelin type-A; and a total of 20 imbibition response proteins involved in energy metabolism, cell growth, cell defense and storage proteins. High temperature inhibited seed germination by decreasing the abundance of proteins involved in methionine metabolism, amino acid biosynthesis, energy metabolism, reserve degradation, protein folding and stress responses. ABA treatment inhibited germination and decreased the abundance of proteins associated with methionine metabolism, energy production and cell division. Our results show that changes in many biological processes including energy metabolism, protein synthesis and cell defense and rescue occurred as a result of all treatments, while enzymes involved in methionine metabolism and weakening of cell wall specifically accumulated when the seeds germinated at the optimal temperature.
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Autophagy promotes radiation-induced senescence but inhibits bystander effects in human breast cancer cells.
Autophagy
PUBLISHED: 04-30-2014
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Ionizing radiation induces cellular senescence to suppress cancer cell proliferation. However, it also induces deleterious bystander effects in the unirradiated neighboring cells through the release of senescence-associated secretory phenotypes (SASPs) that promote tumor progression. Although autophagy has been reported to promote senescence, its role is still unclear. We previously showed that radiation induces senescence in PTTG1-depleted cancer cells. In this study, we found that autophagy was required for the radiation-induced senescence in PTTG1-depleted breast cancer cells. Inhibition of autophagy caused the cells to switch from radiation-induced senescence to apoptosis. Senescent cancer cells exerted bystander effects by promoting the invasion and migration of unirradiated cells through the release of CSF2 and the subsequently activation of the JAK2-STAT3 and AKT pathways. However, the radiation-induced bystander effects were correlated with the inhibition of endogenous autophagy in bystander cells, which also resulted from the activation of the CSF2-JAK2 pathway. The induction of autophagy by rapamycin reduced the radiation-induced bystander effects. This study reveals, for the first time, the dual role of autophagy in radiation-induced senescence and bystander effects.
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[The effect of niflumic acid in hypoxic hypercapnia pulmonary vasoconstriction].
Zhongguo Ying Yong Sheng Li Xue Za Zhi
PUBLISHED: 04-19-2014
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To investigate the effect of chloride channel blocker--niflumic acid (NFA) on the pathological process of hypoxia hypercapnia-induced pulmonary vasoconstriction in rats.
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Bufalin induces cell cycle arrest and apoptosis in gallbladder carcinoma cells.
Tumour Biol.
PUBLISHED: 03-28-2014
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Bufalin, a major digoxin-like immunoreactive component of the Chinese medicine Chan Su, has been shown to exert a potential for anticancer activity against various human cancer cell lines in vitro. However, no detailed studies have so far been reported on its action on human gallbladder carcinoma cells. In this study, bufalin remarkably inhibited growth in human gallbladder cancer cells by decreasing cell proliferation, inducing cell cycle arrest and apoptosis in a dose-dependent manner. Bufalin also disrupted the mitochondrial membrane potential (??m) and regulated the expression of cell cycle and apoptosis regulatory molecules. Activation of caspase-9 and the subsequent activation of caspase-3 indicated that bufalin may be inducing mitochondria apoptosis pathways. Intraperitoneal injection of bufalin for 3 weeks significantly inhibited the growth of gallbladder carcinoma (GBC-SD) xenografts in athymic nude mice. Taken together, the results indicate that bufalin may be a potential agent for the treatment of gallbladder cancer.
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MALAT1 promotes the proliferation and metastasis of gallbladder cancer cells by activating the ERK/MAPK pathway.
Cancer Biol. Ther.
PUBLISHED: 03-21-2014
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Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a long non-coding RNA (lncRNA), is associated with metastasis and is an independent prognostic factor for lung cancer. Recent studies have demonstrated that MALAT1 plays an important role in other malignancies. However, little is known about the role of MALAT1 in gallbladder carcinoma (GBC), which is the most common cancer of the biliary tract and has an extremely poor prognosis. In this study, we focused on the expression, biological functions and mechanism of MALAT1 in GBC and found that MALAT1 was significantly upregulated in GBC tissues compared with corresponding non-cancerous tissues. Knockdown of MALAT1 in GBC cell lines using lentivirus-mediated RNA interference significantly inhibited the proliferation and metastasis of the GBC cells both in vitro and in vivo. Furthermore, ERK/MAPK pathway was found to be inactivated in the GBC cell lines after MALAT1 knockdown. These results indicated that MALAT1 might serve as an oncogenic lncRNA that promotes proliferation and metastasis of GBC and activates the ERK/MAPK pathway.
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Vasoactive intestinal peptide modulation of the steroid-induced LH surge involves kisspeptin signaling in young but not in middle-aged female rats.
Endocrinology
PUBLISHED: 03-21-2014
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Age-related LH surge dysfunction in middle-aged rats is characterized, in part, by reduced responsiveness to estradiol (E2)-positive feedback and reduced hypothalamic kisspeptin neurotransmission. Vasoactive intestinal peptide (VIP) neurons in the suprachiasmatic nucleus project to hypothalamic regions that house kisspeptin neurons. Additionally, middle-age females express less VIP mRNA in the suprachiasmatic nucleus on the day of the LH surge and intracerebroventricular (icv) VIP infusion restores LH surges. We tested the hypothesis that icv infusion of VIP modulates the LH surge through effects on the kisspeptin and RFamide-related peptide-3 (RFRP-3; an estradiol-regulated inhibitor of GnRH neurons) neurotransmitter systems. Brains were collected for in situ hybridization analyses from ovariectomized and ovarian hormone-primed young and middle-aged females infused with VIP or saline. The percentage of GnRH and Kiss1 cells coexpressing cfos and total Kiss1 mRNA were reduced in saline-infused middle-aged compared with young females. In young females, VIP reduced the percentage of GnRH and Kiss1 cells coexpressing cfos, suggesting that increased VIP signaling in young females adversely affected the function of Kiss1 and GnRH neurons. In middle-aged females, VIP increased the percentage of GnRH but not Kiss1 neurons coexpressing cfos, suggesting VIP affects LH release in middle-aged females through kisspeptin-independent effects on GnRH neurons. Neither reproductive age nor VIP affected Rfrp cell number, Rfrp mRNA levels per cell, or coexpression of cfos in Rfrp cells. These data suggest that VIP differentially affects activation of GnRH and kisspeptin neurons of female rats in an age-dependent manner.
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Insulin-like growth factor-I regulates LH release by modulation of kisspeptin and NMDA-mediated neurotransmission in young and middle-aged female rats.
Endocrinology
PUBLISHED: 03-10-2014
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This study investigated potential mechanisms by which age and IGF-I receptor (IGF-Ir) signaling in the neuroendocrine hypothalamus affect estradiol-positive feedback effects on GnRH neuronal activation and on kisspeptin and N-methyl-D-aspartate (NMDA)-induced LH release and on the abundance of NMDA receptor subunits Nr1 and Nr2b and Kiss1r transcript and protein in the hypothalamus of young and middle-aged female rats. We infused vehicle, IGF-I, or JB-1, a selective antagonist of IGF-Ir, into the third ventricle of ovariectomized female rats primed with estradiol or vehicle and injected with vehicle, kisspeptin (3 or 30 nmol/kg), or NMDA (15 or 30 mg/kg). Regardless of dose, NMDA and kisspeptin resulted in significantly more LH release, GnRH/c-Fos colabeling, and c-Fos immunoreative cells in young than in middle-aged females. Estradiol priming significantly increased Kiss1r, Nr1, and Nr2b receptor transcript and protein abundance in young but not middle-aged female hypothalamus. JB-1 attenuated kisspeptin and NMDA-induced LH release, numbers of GnRH/c-Fos and c-Fos cells, and Kiss1r, Nr1, and Nr2b transcript and protein abundance in young females to levels observed in middle-aged females. IGF-I significantly enhanced NMDA and kisspeptin-induced LH release in middle-aged females without increasing numbers of GnRH/c-Fos or c-Fos immunoreactive cells. IGF-I infusion in middle-aged females also increased Kiss1r, Nr1, and Nr2b protein and transcript to levels that were equivalent to young estradiol-primed females. These findings indicate that age-related changes in estradiol-regulated responsiveness to excitatory input from glutamate and kisspeptin reflect reduced IGF-Ir signaling.
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Association between melatonin receptor 1A (MTNR1A) gene single-nucleotide polymorphisms and the velvet antler yield of Sika deer.
Mol. Biol. Rep.
PUBLISHED: 03-05-2014
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Melatonin, a secretion from pineal gland is ambiguously considered as the key hormone involved in regulation of the antler cycle in Sika deer. To find out more about the roles of melatonin and its receptor gene, we carried out current study to investigate the association between polymorphisms in melatonin receptor 1A (MTNR1A) gene and the antler yield from Sika deer. A total of 251 Sika deer were analyzed in this study, of which consisted of Wusan Sika deer (n = 163) and Dongfeng Sika deer (n = 88). MTNRA gene was amplified by PCR and genotyped by Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Three polymorphism loci (C518T, C629G and C635T) were detected in exon2 of MTNR1A gene. The restriction site Ecol881 was used for C518T while a C629G polymorphism locus was digested with Mval restriction endonucleases. In Wusan Sika deer the allele frequencies of C and T were 0.637 and 0.363 for C518T, Also C and G alleles in C629G locus were 0.206 and 0.794. Genotypic frequencies of allele CC, CT and TT were 33.7, 59.9 and 6.4 % respectively, It showed 1.8, 37.4 and 60.7 % for frequencies of genotypes CC, CG and GG. In Dongfeng Sika deer the allele frequencies of C and T were 0.518 and 0.482 for C518T, C and G alleles were 0.375 and 0.625 for C629G. Genotypic frequencies were 10.6, 82.4 and 7.1 % for genotypes CC, CT and TT respectively, and they were 1.1, 72.7 and 26.2 % for genotypes CC, CG and GG. Among three SNPs, only C629G showed significant association (P < 0.05) with average antler yield in Wusan Sika deer, while no SNP was significant in Dongfeng Sika deer. These preliminary results implied that the identified SNPs of MTNR1A gene might influence the antler yield in Wusan Sika deer.
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Infantile Hemangioma-Like Vascular Lesion in a 26-Year-Old Woman after Abortion.
Dermatology (Basel)
PUBLISHED: 02-21-2014
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A 26-year-old woman (G2P1A1) presented with a 5-week history of multiple red marks on her body after a therapeutic abortion. A physical examination found 15 palpable red marks on her head, neck, chest, arms and legs. Proliferating endothelial cells, which expressed CD31, CD34, von Willebrand factor, but not Glut-1 and merosin, were observed in the lesional area by histopathological analyses. Histocompatibility antigen typing of 2 lesions was identical to a sample from peripheral blood. Accelerated regression was observed in 2 lesions treated by intralesional injection of betamethasone, while spontaneous regression was observed within 9 months in the remaining lesions without any treatment. Rapid growth, spontaneous regression and histological analyses in this case support the diagnosis of 'infantile hemangioma-like vascular lesion'. © 2014 S. Karger AG, Basel.
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Effect of obesity on the association between common variations in the PPAR gene and C-reactive protein level in Chinese Han population.
Endocrine
PUBLISHED: 02-14-2014
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The peroxisome proliferator-activated receptors (PPARs)-?, -?/?, and -? are the ligand-activated transcription factors that function as the master regulators of glucose, fatty acid and lipoprotein metabolism, inflammation, and atherosclerosis. Our aim was to test the association between ten single nucleotide polymorphisms of PPARs and CRP level, as well as their interaction with overweight/obesity. A sample population of 643 subjects was recruited from the prevention of MetS and multi-metabolic disorders in Jiangsu Province of China Study. The selected SNPs in PPAR ? (rs135539, rs4253778, rs1800206), PPAR ?/? (rs2016520 and rs9794), and PPAR ? (rs10865710, rs1805192, rs709158, rs3856806, and rs4684847) were genotyped. After adjustment for smoking, alcohol consumption, SBP, DBP, TG, and HDL-C, rs1800206, rs709158, rs1805192, and rs4684847 polymorphisms were significantly associated with CRP level in normal weight subjects (P < 0.05). In the overweight/obese subjects, rs1800206 was also significant associated with CRP level (P < 0.01). In addition, the rs709158, rs1805192, and rs4684847 polymorphisms were shown interactions with overweight/obesity to influence CRP level (P < 0.05). PPARs polymorphisms are independently associated with CRP levels in Chinese Han population. Further, PPARs polymorphisms interact with overweight/obesity to set CRP levels.
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Triptolide induces s phase arrest and apoptosis in gallbladder cancer cells.
Molecules
PUBLISHED: 02-13-2014
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Gallbladder carcinoma is the most common malignancy of the biliary tract, with a very low 5-year survival rate and extremely poor prognosis. Thus, new effective treatments and drugs are urgently needed for the treatment of this malignancy. In this study, for the first time we investigated the effects of triptolide on gallbladder cancer cells and identified the mechanisms underlying its potential anticancer effects. The MTT assay showed that triptolide decreased cell viability in a dose- and time-dependent manner. The results of the colony formation assay indicated that triptolide strongly suppressed colony formation ability in GBC-SD and SGC-996 cells. Flow cytometric analysis revealed that triptolide induced S phase arrest in gallbladder cancer cells. In addition, triptolide induced apoptosis, as shown by the results of annexin V/propidium iodide double-staining and Hoechst 33342 staining. Furthermore, triptolide decreased mitochondrial membrane potential (??m) in a dose-dependent manner. Finally, western blot analysis of triptolide-treated cells revealed the activation of caspase-3, caspase-9, PARP, and Bcl-2; this result demonstrated that triptolide induced apoptosis in gallbladder cancer cells by regulating apoptosis-related protein expression, and suggests that triptolide may be a promising drug to treat gallbladder carcinoma.
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Baicalin induces apoptosis of gallbladder carcinoma cells in vitro via a mitochondrial-mediated pathway and suppresses tumor growth in vivo.
Anticancer Agents Med Chem
PUBLISHED: 02-02-2014
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Baicalin, the main active ingredient in the Scutellaria baicalensis (SB), is prescribed for the treatment of various inflammatory diseases and tumors in clinics in China. In the present study, we evaluated the antitumor activity of baicalin for gallbladder carcinoma and the underlying mechanisms both in vitro and in vivo. Our results indicate that baicalin induced potent growth inhibition, cell cycle arrest, apoptosis and colony-formation inhibition in a dose-dependent manner in vitro. We observed inhibition of NF-?B nuclear translocation, up-regulation of Bax and down-regulation of Bcl-2, as well as increased caspase-3 and caspase-9 expression after baicalin treatment in vitro and in vivo, which indicates that the mitochondrial pathway was involved in baicalin-induced apoptosis. In addition, daily intraperitoneally injection of baicalin (15, 30 and 60 mg/kg) for 21 days significantly inhibited the growth of NOZ cells xenografts in nude mice, which improved the survival of baicalin-treated mice. In summary, baicalin exhibited a significant anti-tumor effect by suppressing cell proliferation, promoting apoptosis, and inducing cell cycle arrest in vitro, and by suppressing tumor growth and improving survival in vivo, which suggested that baicalin represents a novel therapeutic option for gallbladder carcinoma.
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Esophageal Helicobacter pylori colonization aggravates esophageal injury caused by reflux.
World J. Gastroenterol.
PUBLISHED: 01-30-2014
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To investigate esophageal Helicobacter pylori (H. pylori) colonization on esophageal injury caused by reflux and the related mechanisms.
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PPAR ? and PPAR ? polymorphisms as risk factors for dyslipidemia in a Chinese Han population.
Lipids Health Dis
PUBLISHED: 01-24-2014
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The PPAR ? and PPAR ? are the key messengers responsible for the translation of nutritional stimuli into changes for the expression of genes, particularly genes involved in lipid metabolism. However, the associations between PPAR ?/? polymorphisms and lipid serum levels in the general population were rarely studied, and the conclusions were conflicting. The objective was to investigate the associations of the PPAR ? and PPAR ? polymorphisms with dyslipidemia.
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Ursolic acid induces cell cycle arrest and apoptosis of gallbladder carcinoma cells.
Cancer Cell Int.
PUBLISHED: 01-01-2014
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Ursolic acid (UA), a plant extract used in traditional Chinese medicine, exhibits potential anticancer effects in various human cancer cell lines in vitro. In the present study, we evaluated the anti-tumoral properties of UA against gallbladder carcinoma and investigated the potential mechanisms responsible for its effects on proliferation, cell cycle arrest and apoptosis in vitro.
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Study on the expressions of PHD and HIF in placentas from normal pregnant women and patients with preeclampsia.
Int. J. Biol. Sci.
PUBLISHED: 01-01-2014
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To investigate the relationship between oxygen sensitivity of trophoblast and hypoxia in preeclamptic placenta by the study on the expressions of hypoxia-inducible factor prolyl 4-hydroxylase (PHD) and hypoxia-inducible factor (HIF) in placentas from normal pregnant women and patients with pre-eclampsia.
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Exploring candidate genes for pericarp russet pigmentation of sand pear (Pyrus pyrifolia) via RNA-Seq data in two genotypes contrasting for pericarp color.
PLoS ONE
PUBLISHED: 01-01-2014
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Sand pear (Pyrus pyrifolia) russet pericarp is an important trait affecting both the quality and stress tolerance of fruits. This trait is controlled by a relative complex genetic process, with some fundamental biological questions such as how many and which genes are involved in the process remaining elusive. In this study, we explored differentially expressed genes between the russet- and green-pericarp offspring from the sand pear (Pyrus pyrifolia) cv. 'Qingxiang' × 'Cuiguan' F1 group by RNA-seq-based bulked segregant analysis (BSA). A total of 29,100 unigenes were identified and 206 of which showed significant differences in expression level (log2fold values>1) between the two types of pericarp pools. Gene Ontology (GO) analyses detected 123 unigenes in GO terms related to 'cellular_component' and 'biological_process', suggesting developmental and growth differentiations between the two types. GO categories associated with various aspects of 'lipid metabolic processes', 'transport', 'response to stress', 'oxidation-reduction process' and more were enriched with genes with divergent expressions between the two libraries. Detailed examination of a selected set of these categories revealed repressed expressions of candidate genes for suberin, cutin and wax biosynthesis in the russet pericarps.Genes encoding putative cinnamoyl-CoA reductase (CCR), cinnamyl alcohol dehydrogenase (CAD) and peroxidase (POD) that are involved in the lignin biosynthesis were suggested to be candidates for pigmentation of sand pear russet pericarps. Nine differentially expressed genes were analyzed for their expressions using qRT-PCR and the results were consistent with those obtained from Illumina RNA-sequencing. This study provides a comprehensive molecular biology insight into the sand pear pericarp pigmentation and appearance quality formation.
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[The role of preoperative TACE on hepatocellular carcinoma located in caudate lobe].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 12-17-2013
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To evaluate the effect of preoperative transarterial chemoembolization (TACE) on hepatocellular carcinoma located in caudate lobe.
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[Surgical treatment of primary hyperparathyroidism].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 12-17-2013
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To investigate the causes of misdiagnosis and the surgical treatment of primary hyperparathyroidism (PHPT).
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Nucleolin is important for Epstein-Barr virus nuclear antigen 1-mediated episome binding, maintenance, and transcription.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 12-16-2013
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Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is essential for EBV episome maintenance, replication, and transcription. These effects are mediated by EBNA1 binding to cognate oriP DNA, which comprise 20 imperfect copies of a 30-bp dyad symmetry enhancer and an origin for DNA replication. To identify cell proteins essential for these EBNA1 functions, EBNA1 associated cell proteins were immune precipitated and analyzed by liquid chromatography-tandem mass spectrometry. Nucleolin (NCL) was identified to be EBNA1 associated. EBNA1s N-terminal 100 aa and NCLs RNA-binding domains were critical for EBNA1/NCL interaction. Lentivirus shRNA-mediated NCL depletion substantially reduced EBNA1 recruitment to oriP DNA, EBNA1-dependent transcription of an EBV oriP luciferase reporter, and EBV genome maintenance in lymphoblastoid cell lines. NCL RNA-binding domain K429 was critical for ATP and EBNA1 binding. NCL overexpression increased EBNA1 binding to oriP and transcription, whereas NCL K429A was deficient. Moreover, NCL silencing impaired lymphoblastoid cell line growth. These experiments reveal a surprisingly critical role for NCL K429 in EBNA1 episome maintenance and transcription, which may be a target for therapeutic intervention.
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Modulation of chondrocyte functions and stiffness-dependent cartilage repair using an injectable enzymatically crosslinked hydrogel with tunable mechanical properties.
Biomaterials
PUBLISHED: 10-31-2013
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We developed an injectable hydrogel system to evaluate the effect of hydrogel stiffness on chondrocyte cellular functions in a three-dimensional (3D) environment and its subsequent influence on ectopic cartilage formation and early-stage osteochondral defect repair in a rabbit model. The hydrogels, composed of gelatin-hydroxyphenylpropionic acid (Gtn-HPA) conjugate, were formed using oxidative coupling of HPA moieties catalyzed by hydrogen peroxide (H2O2) and horseradish peroxidase (HRP). The storage modulus (G) of the hydrogels, which was tunable by changing the H2O2 and Gtn-HPA concentrations, ranged from 570 Pa to 2750 Pa. It was found that the cellular functions of chondrocytes encapsulated in hydrogels, including cell proliferation, biosynthesis of collagen and sulfated glycosaminoglycans (sGAG), as well as gene expression of type I (Col-I) and type II collagen (Col-II), were strongly affected by the stiffness of the hydrogels. Of note, chondrocytes cultured within the Gtn-HPA hydrogel of medium stiffness (G = 1000 Pa) produced highest level of sGAG production, as well as highest ratio of Col-II to Col-I gene expression among the Gtn-HPA hydrogels of different stiffness. Consistent with the results from in vitro and in vivo ectopic cartilage formation, osteochondral defect repair in a rabbit model showed stiffness-dependent tissue repair, with defects implanted with chondrocytes in hydrogels of medium stiffness having markedly more hyaline cartilage formation, smoother surface and better integration with adjacent cartilage, compared to defects treated with hydrogels of low or high stiffness. These results suggest that the tunable stiffness of Gtn-HPA hydrogels modulates chondrocyte cellular functions, and has a dramatic impact on cartilage tissue histogenesis and repair.
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[Roles of peroxisome proliferator-activated receptors polymorphisms, haplotypes, levels on C-reactive protein and their interactions with abnormal body weight].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 10-08-2013
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To explore the roles of peroxisome proliferator-activated receptors (PPARs) on the levels of serum C-reactive protein(CRP)and the interactions of PPARs haplotypes with abnormal body weight.
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[Inhibitory effects of celecoxib combined with capecitabine on H22 hepatoma mice and its mechanism].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 08-31-2013
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To evaluate the inhibitory effect and its mechanism of celecoxib combined with capecitabine on the growth of implanted H22 hepatoma in mice.
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Detection of pelvic lymph node micrometastasis by real-time reverse transcriptase polymerase chain reaction in prostate cancer patients after hormonal therapy.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 08-12-2013
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To determine the feasibility of prostatic-specific antigen (PSA) mRNA and prostatic-specific membrane antigen (PSMA) mRNA measurement in detection of pelvic lymph node (PLN) micrometastasis for prostate cancer (PCa) after hormonal therapy (HT).
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[Analysis of clinical features and early warning indicators of death from hand, foot and mouth disease in Shandong province].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 08-10-2013
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To understand the clinical features of death from hand, foot and mouth disease (HFMD) and to explore the early warning index of HFMD death.
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Characterization of a marine-derived dextranase and its application to the prevention of dental caries.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 08-05-2013
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The dextranase added in current commercial dextranase-containing mouthwashes is largely from fungi. However, fungal dextranase has shown much higher optimum temperature than bacterial dextranase and relatively low activity when used in human oral cavities. Bacterial dextranase has been considered to be more effective and suitable for dental caries prevention. In this study, a dextranase (Dex410) from marine Arthrobacter sp. was purified and characterized. Dex410 is a 64-kDa endoglycosidase. The specific activity of Dex410 was 11.9 U/mg at optimum pH 5.5 and 45 °C. The main end-product of Dex410 was isomaltotriose, isomaltoteraose, and isomaltopentaose by hydrolyzing dextran T2000. In vitro studies showed that Dex410 effectively inhibited the Streptococcus mutans biofilm growth in coverage, biomass, and water-soluble glucan (WSG) by more than 80, 90, and 95 %, respectively. The animal experiment revealed that for short-term use (1.5 months), both Dex410 and the commercial mouthwash Biotene (Laclede Professional Products, Gardena, CA, USA) had a significant inhibitory effect on caries (p = 0.0008 and 0.0001, respectively), while for long-term use (3 months), only Dex410 showed significant inhibitory effect on dental caries (p = 0.005). The dextranase Dex410 from a marine-derived Arthrobacter sp. strain possessed the enzyme properties suitable to human oral environment and applicable to oral hygiene products.
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[Clinical study of repairing donor site of thickness from cicatricial skin with auto-scalp grafting].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-19-2013
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To study the effects of using auto-scalp for repairing donor site of thickness from cicatricial skin with auto-scalp grafting.
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Galactose-functionalized cationic polycarbonate diblock copolymer for targeted gene delivery to hepatocytes.
Macromol Rapid Commun
PUBLISHED: 07-15-2013
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To mediate selective gene delivery to hepatocytes via the asialoglycoprotein receptors (ASGP-Rs), we designed and synthesized well-defined and narrowly dispersed galactose- and glucose-functionalized cationic polycarbonate diblock copolymers (designated as Gal-APC and Glu-APC, respectively) using organocatalytic ring-opening polymerization of functionalized carbonate monomers, with a subsequent quaternization step using bis-tertiary amines to confer quaternary and tertiary amines for DNA binding and endosomal buffering, respectively. The sugar-functionalized diblock copolymers effectively bound and condensed DNA to form positively charged nanoparticles (<100 nm in diameter and ?30 mV zeta-potential) that were stable under high physiological salt conditions. In comparison to the control Glu-APC/DNA complexes, Gal-APC/DNA complexes mediated significantly higher gene expression in ASGP-R positive HepG2 cells with no significant difference observed in ASGP-R negative HeLa cells. The co-incubation of Gal-APC/DNA complexes with a natural ASGP-R ligand effectively led to a decrease in gene expression, hence providing evidence for the ASGP-R mediated endocytosis of the polyplexes. Importantly, the Gal-APC/DNA complexes induced minimal cytotoxicities in HepG2 cells at the N/P ratios tested. Taken together, the galactose-functionalized cationic polycarbonate diblock copolymer has potential for use as a non-viral gene vector for the targeted delivery of therapeutic genes to hepatocytes in the treatment of liver diseases.
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Job satisfaction and work related variables in Chinese cardiac critical care nurses.
J Nurs Manag
PUBLISHED: 07-03-2013
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To explore critical care nurses views of their job satisfaction and the relationship with job burnout, practice environment, coping style, social support, intention to stay in current employment and other work-related variables.
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Ginsenoside Rg1 reduces toxicity of fine particulate matter on human alveolar epithelial cells: A preliminary observation.
Mol Med Rep
PUBLISHED: 06-27-2013
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Fine particulate matter (PM2.5) is a significant environmental pollutant responsible for a number of human diseases. Ginsenoside Rg1 (Rg1) is likely to have the potential to relieve PM2.5?induced cell injury. The present study is designed to preliminarily observe the harmful effect of PM2.5 and the protective effect of Rg1 against PM2.5 on human A549 lung epithelial cells in vitro. The cytotoxic effects of the PM2.5 or Rg1 on A549 cells were measured by means of cell viability, and then exposure concentration of PM2.5 and pretreatment concentration of Rg1 used in the following assays were established. The A549 cells were pretreated with Rg1 for 1 h and then exposed to PM2.5 for 24 h. The levels of lactate dehydrogenase (LDH) in the cell culture supernatant and malondialdehyde (MDA) within the cells were assayed. The present results revealed that 200?1,200 µg/ml of PM2.5 decreased the viability of A549 cells significantly in a concentration?dependent manner; however, 50?400 µg/ml of Rg1 had no significant effect. Pretreatment with 100, 200 or 400 µg/ml Rg1 significantly diminished the 200 µg/ml PM2.5?induced A549 cell viability and decreased LDH leakage and MDA generation in a concentration?dependent manner. These results indicated that PM2.5 induced cell injury and Rg1, antagonized PM2.5?induced cell injury to a certain extent.
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[Comparing microbial community of high ammonia wastewater and municipal sewage in a partial nitrification system].
Huan Jing Ke Xue
PUBLISHED: 06-27-2013
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Nitritation is an important part of the biological nitrogen removal process, and the performance of the process was determined by the microbial community structure. To explore the microbial adaptability to different sewage, the microbial diversity and the amount of bacteria were investigated in a high ammonia wastewater treatment process and a sewage treatment process using the clone library of bacterial 16S rDNA, the phospholipid fatty acid method (PLFA) and the quantitative PCR. The clone library results showed that there was a significantly difference in bacterial community structure of these two processes, although the dominant bacteria belong to the Proteobacteria and Bacteroidete, there were more clusters in the sewage treatment process. The PLFAs results showed that the microbial diversity index and the evenness index of the high ammonium wastewater treatment process were significantly low. The quantitative PCR results showed that amounts of ammonia oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) in the high ammonium wastewater treatment process were higher than these in sewage treatment process. The copy number of AOB was higher than the copy number of NOB in the high ammonia wastewater treatment process by three orders magnitude. The copy number of AOB was higher than the copy number of NOB in sewage treatment process by two orders of magnitude.
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Genetic variants of Orientia tsutsugamushi in domestic rodents, northern China.
Emerging Infect. Dis.
PUBLISHED: 06-15-2013
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We screened Orientia tsutsugamushi from 385 domestic rodents and 19 humans with scrub typhus in rural Taian District, Shandong Province, a new scrub typhus epidemic area in northern China. Sequence analysis identified 7 genotypes in the rodents, of which 2 were also identified in the humans.
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mPlum-IFP 1.4 fluorescent fusion protein may display Förster resonance energy transfer associated properties that can be used for near-infrared based reporter gene imaging.
J Biomed Opt
PUBLISHED: 06-04-2013
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ABSTRACT. Bacteriophytochrome infrared fluorescent protein (IFP) has a long emission wavelength that is appropriate for detecting pathophysiological effects via near-infrared (NIR) based imaging. However, the brightness and photostability of IFP are suboptimal, although an exogenous supply of biliverdin (BV) IX? is able to enhance these properties. In this study, we fused a far red mPlum fluorescent protein to IFP 1.4 via a linker deoxyribonucleic acid (DNA) sequence encoding eight amino acids. The brightness of mPlum-IFP 1.4 fusion protein at the IFP emission channel was comparable to that of native IFP 1.4 protein when fusion protein and IFP 1.4 were excited by 543 and 633 nm using confocal microscopy, respectively. Visualization of IFP 1.4 fluorescence by excitation of mPlum in mPlum-IFP 1.4 fusion protein is likely to be associated with Förster resonance energy transfer (FRET). The FRET phenomenon was also predicted by acceptor photobleaching using confocal microscopy. Furthermore, the expression of mPlum-IFP 1.4 fusion protein could be detected in cell culture and in xenograft tumors in the absence of BV using in vivo imaging system, although the BV was still essential for detecting native IFP 1.4. Therefore, this innovativefluorescent fusion protein would be useful for NIR-based imaging in vitro and in vivo.
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Colorectal cancer screening with fecal occult blood test: A 22-year cohort study.
Oncol Lett
PUBLISHED: 05-30-2013
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The aim of the present study was to investigate the efficacy of colorectal cancer (CRC) screening with a three-tier fecal occult blood test (FOBT) in the Chinese population. The study was performed between 1987 and 2008 at the Beijing Military General Hospital, in a cohort of army service males and females aged >50 years. Between 1987 and 2005, a three-tier screening program, comprising guaiac-based FOBTs (gFOBTs), followed by immunochemical FOBTs for positive guaiac test samples and then colonoscopy for positive immunochemical test subjects, was performed annually. The cohort was followed up until 2008. The cohort included 5,104 subjects, of which, 3,863 subjects participated in screening (screening group) and 1,241 did not (non-screening group). The two groups did not differ in age, gender or other major risk factors for colon cancer. Overall, 36 CRCs occurred in the screening group and 21 in the non-screening group. Compared with the non-screening group, the relative risk for the incidence and mortality of CRC was 0.51 [95% confidence interval (CI), 0.30-0.87] and 0.36 (95% CI, 0.18-0.71), respectively, in the screening group. The general sensitivity of this three-tier FOBT was 80.6% (95% CI, 65.3-91.1). Thus, annual screening using the three-tier FOBT program may reduce the CRC incidence and mortality rate.
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Cytochrome P450 2A6 deletion polymorphism and risk of lung cancer: a meta-analysis.
Mol. Biol. Rep.
PUBLISHED: 04-30-2013
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Previous studies concerning the association between cytochrome P450 2A6 (CYP2A6) deletion polymorphism and lung cancer risk provided controversial results. To clarify the precise association, a meta-analysis was performed. The electronic databases PubMed, Chinese Biomedical Database and Chinese National Knowledge Infrastructure Database were searched for case-control studies last updated on June 3, 2012 that investigated CYP2A6 deletion polymorphism and lung cancer risk. The odds ratio (OR) and its respective 95 % confidence interval (95 % CI) were used to measure the strength of association by means of a genetic model free approach. A total of 8 studies including 2,607 cases and 2,595 controls met the inclusion criteria and were subjected to the final analysis. The most appropriate co-dominant model was adopted. Overall, we found that CYP2A6 *1/*1 genotype was associated with an increased risk of lung cancer relative to *4/*4 genotype (OR = 2.65, 95 % CI: 1.84-3.81, P < 0.001). Significant association was also detected among Asians. Publication bias was absent in this meta-analysis. Therefore, our data suggested that the presence of the CYP2A6 *1/*1 might be associated with an increased lung cancer risk, especially for Asians. Further studies well-designed among different ethnicity populations are required.
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One-pot green synthesis of graphene oxide/gold nanocomposites as SERS substrates for malachite green detection.
Analyst
PUBLISHED: 04-16-2013
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In this contribution, graphene oxide/gold nanoparticle (GO/AuNPs) hybrids were in situ fabricated through a green one-pot procedure by using tyrosine as an environment friendly and biocompatible reducing agent, which can be used as highly efficient surface enhanced Raman scattering (SERS) substrates with the enhancement factor at 3.8 × 10(3). The as-prepared GO/AuNPs hybrids have good biocompatibility, providing the prospect of applications for biomedicine determinations. In addition, taking the advantages of the electromagnetic and chemical enhancement mechanism and the high affinity of GO and AuNPs towards positive dyes, a sensitive, selective and label-free malachite green (MG) detection method was demonstrated. The SERS measurement showed that the minimum detection concentration of MG in water was as low as 2.5 ?mol L(-1) with a linear response range from 2.5 to 100 ?mol L(-1) (R(2) = 0.996). Moreover, this method can be applied to detect MG in a fishery water sample with satisfactory results.
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Evaluation of Two Inflammation-Based Prognostic Scores in Patients with Resectable Gallbladder Carcinoma.
Ann. Surg. Oncol.
PUBLISHED: 04-06-2013
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Survival after surgery for gallbladder cancer is generally poor. A number of inflammation-based prognostic scores have been established to help predict survival after surgery for several types of cancer. The objective of this study was to analyze and compare the utility of two inflammation-based prognostic scores, the Glasgow prognostic score (GPS) and the neutrophil-to-lymphocyte ratio (NLR), for predicting survival in patients with gallbladder cancer after surgery with curative intent.
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Encapsulated human hepatocellular carcinoma cells by alginate gel beads as an in vitro metastasis model.
Exp. Cell Res.
PUBLISHED: 04-05-2013
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Hepatocellular carcinoma (HCC) is the most common primary liver cancer and often forms metastases, which are the most important prognostic factors. For further elucidation of the mechanism underlying the progression and metastasis of HCC, a culture system mimicking the in vivo tumor microenvironment is needed. In this study, we investigated the metastatic ability of HCC cells cultured within alginate gel (ALG) beads. In the culture system, HCC cells formed spheroids by proliferation and maintained in nuclear abnormalities. The gene and protein expression of metastasis-related molecules was increased in ALG beads, compared with the traditional adhesion culture. Furthermore, several gene expression levels in ALG bead culture system were even closer to liver cancer tissues. More importantly, in vitro invasion assay showed that the invasion cells derived from ALG beads was 7.8-fold higher than adhesion cells. Our results indicated that the in vitro three-dimensional (3D) model based on ALG beads increased metastatic ability compared with adhesion culture, even partly mimicked the in vivo tumor tissues. Moreover, due to the controllable preparation conditions, steady characteristics and production at large-scale, the 3D ALG bead model would become an important tool used in the high-throughput screening of anti-metastasis drugs and the metastatic mechanism research.
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Association of peroxisome proliferator-activated receptor ? polymorphisms and haplotypes with essential hypertension.
Genet Test Mol Biomarkers
PUBLISHED: 03-26-2013
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Peroxisome proliferator-activated receptor ? (PPAR?) is a nuclear receptor involved in the regulation of several biochemical pathways. Blood pressure-lowering effects have been found in PPAR? agonists in several hypertensive models. The biology and research data related to the gene suggest that it could play a role in essential hypertension (EH) susceptibility. This study aimed to investigate the association between PPAR? polymorphisms and EH. About 820 subjects were genotyped for the three single-nucleotide polymorphisms used as genetic markers for the PPAR? genes (C681G, Prol2Ala, and C1431T). After correction for age, sex, smoking, alcohol consumption, body mass index, waist circumference, and fasting glucose, the G allele (CG+GG) of C681G was significantly associated with the increase in the risk of EH (odds ratio [OR]=1.54, 95%confidence interval [CI]: 1.14-2.09, p=0.005). The A allele (PA+PP) of Pro12Ala was significantly associated with the decrease in the risk of EH (OR=0.70, 95%CI: 0.52-0.95, p=0.020). However, C1431T was not significantly associated with EH. Generalized multifactor dimensionality reduction analysis showed that there was a potential gene-gene interaction between C681G and Prol2Ala (p=0.0107). The G-P haplotype (established by C681G, Prol2Ala) was significantly associated with increase in the risk of EH (OR=1.53, 95%CI:1.13-2.07, p=0.006). In conclusion, PPAR? polymorphisms and haplotypes were significantly associated with hypertension susceptibility.
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The effect of electrostatic microencapsulation process on biological properties of tumour cells.
J Microencapsul
PUBLISHED: 03-20-2013
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Microencapsulation is one of the promising strategies to develop a three-dimensional in vivo tumour-mimic model in cancer research. Although previous studies have shown that tumour cells grow well during the microencapsulated culture, it is still not clear whether the electrostatic encapsulation process has an important effect on cellular characteristics. In this study, we investigated cellular response against non-physiological stress factors existing in the electrostatic microencapsulation process, such as the high-voltage electrostatic field, suspension and nutrition-free status. Our results showed that these non-physiological stress factors did not significantly induce cellular apoptosis, and did not affect cellular adhesion and viability. Furthermore, no change was found about invasion and drug resistance of the tumour cells. The normal endoplasmic reticulum function might play a role in maintaining biological properties during the electrostatic microencapsulation process.
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Enhanced cellular radiosensitivity induced by cofilin-1 over-expression is associated with reduced DNA repair capacity.
Int. J. Radiat. Biol.
PUBLISHED: 03-19-2013
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A previous report has indicated that over-expression of cofilin-1 (CFL-1), a member of the actin depolymerizing factor (ADF)/cofilin protein family, enhances cellular radiosensitivity. This study explores the involvement of various DNA damage responses and repair systems in the enhanced cellular radiosensitivity as well as assessing the role of CFL-1 phosphorylation in radiosensitivity.
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[Effect of gambogic acid on proliferation of SKM-1 cells and its mechanism].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 03-15-2013
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The aim of this study was to explore the effect of gambogic acid (GA) on MDS SKM-1 cell proliferation, apoptosis and their possible mechanism. Cell proliferation was determined by MTT method. The apoptosis percentage and cell cycle regulation of SKM-1 cells were analyzed by flow cytometry. Morphological features were observed by light microscopy. The mRNA expression of bcl-2 and bax were detected by RT-PCR. The results showed that GA could inhibit the proliferation of SKM-1 cells in a dose- and time-dependent manner (IC50 was 0.37 µg/ml at 48 h), increase the apoptotic percentage of SKM-1 cells, and arrest cell cycle at the G0/G1. The expression of bax mRNA was up-regulated while that of bcl-2 mRNA was down-regulated in SKM-1 cells treated with GA for 48 h. It is concluded that GA can induce apoptosis, which may be related to its effect of arresting cells at phase of G0/G1 and down-regulating bcl-2/bax ratio.
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Metal-enhanced fluorescence of nano-core-shell structure used for sensitive detection of prion protein with a dual-aptamer strategy.
Anal. Chim. Acta
PUBLISHED: 02-26-2013
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Metal-enhanced fluorescence (MEF) as a newly recognized technology is widespread throughout biological research. The use of fluorophore-metal interactions is recognized to be able to alleviate some of fluorophore photophysical constraints, favorably increase both the fluorophore emission intensity and photostability. In this contribution, we developed a novel metal-enhanced fluorescence (MEF) and dual-aptamer-based strategy to achieve the prion detection in solution and intracellular protein imaging simultaneously, which shows high promise for nanostructure-based biosensing. In the presence of prion protein, core-shell Ag@SiO2, which are functionalized covalently by single stranded aptamer (Apt1) of prions and Cyanine 3 (Cy3) decorated the other aptamer (Apt2) were coupled together by the specific interaction between prions and the anti-prion aptamers in solution. By adjusting shell thickness of the pariticles, a dual-aptamer strategy combined MEF can be realized by the excitation and/or emission rates of Cy3. It was found that the enhanced fluorescence intensities followed a linear relationship in the range of 0.05-0.30 nM, which is successfully applied to the detection of PrP in mice brain homogenates.
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A visual dual-aptamer logic gate for sensitive discrimination of prion diseases-associated isoform with reusable magnetic microparticles and fluorescence quantum dots.
PLoS ONE
PUBLISHED: 02-05-2013
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Molecular logic gates, which have attracted increasing research interest and are crucial for the development of molecular-scale computers, simplify the results of measurements and detections, leaving the diagnosis of disease either "yes" or "no". Prion diseases are a group of fatal neurodegenerative disorders that happen in human and animals. The main problem with a diagnosis of prion diseases is how to sensitively and selectively discriminate and detection of the minute amount of PrP(Res) in biological samples. Our previous work had demonstrated that dual-aptamer strategy could achieve highly sensitive and selective discrimination and detection of prion protein (cellular prion protein, PrP(C), and the diseases associated isoform, PrP(Res)) in serum and brain. Inspired by the advantages of molecular logic gate, we further conceived a new concept for dual-aptamer logic gate that responds to two chemical input signals (PrP(C) or PrP(Res) and Gdn-HCl) and generates a change in fluorescence intensity as the output signal. It was found that PrP(Res) performs the "OR" logic operation while PrP(C) performs "XOR" logic operation when they get through the gate consisted of aptamer modified reusable magnetic microparticles (MMPs-Apt1) and quantum dots (QDs-Apt2). The dual-aptamer logic gate simplifies the discrimination results of PrP(Res), leaving the detection of PrP(Res) either "yes" or "no". The development of OR logic gate based on dual-aptamer strategy and two chemical input signals (PrP(Res) and Gdn-HCl) is an important step toward the design of prion diseases diagnosis and therapy systems.
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A graphene oxide enhanced fluorescence anisotropy strategy for DNAzyme-based assay of metal ions.
Chem. Commun. (Camb.)
PUBLISHED: 01-31-2013
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Graphene oxide (GO) introduced to enhance the fluorescence anisotropy (FA) of fluorogens was identified to be effective for highly sensitive and selective detection of metal ions through an anisotropy DNAzyme-based strategy.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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