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Find video protocols related to scientific articles indexed in Pubmed.
An additive-free synthesis of In2O3 cubes embedded into graphene sheets and their enhanced NO2 sensing performance at room temperature.
ACS Appl Mater Interfaces
PUBLISHED: 11-18-2014
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In this report, we developed an additive-free synthesis of In2O3 cubes embedded into graphene networks with InN nanowires (InN-NWs) and graphene oxide (GO) as precursors by a facile one-step microwave-assisted hydrothermal method. In absence of GO, the InN-NWs maintained their chemical composition and original morphology upon the same treatment. At varying mass ratios of InN-NWs and GO, the different morphologies and distributions of In2O3 could be obtained on graphene sheets. The uniform distribution, which is usually considered favorable for enhanced sensing performance, was observed in In2O3 cubes/reduced graphene oxide (rGO) composites. The room-temperature NO2 sensing properties of the In2O3 cubes/rGO composites-based sensor were systematically investigated. The results revealed that the sensor exhibited a significant response to NO2 gas with a concentration lower to 1 ppm, and an excellent selectivity, even though the concentrations of interferential gases were 1000 times that of NO2. The enhanced NO2 sensing performances were attributed to the synergistic effect of uniformly distributed In2O3 cubes and graphene sheets in the unique hybrid architectures without the interfering of extra additives.
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Multi-residue Method for Determination of 238 Pesticides in Chinese Cabbage and Cucumber by Liquid Chromatography-Tandem Mass Spectrometry: Comparison of Different Purification Procedures.
J. Agric. Food Chem.
PUBLISHED: 11-08-2014
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This paper describes the comparison of five sample cleanup procedures for the determination of 238 pesticides via triple quadrupole liquid chromatography-tandem mass spectrometry (LC-MS/MS, with only 10 min of chromatographic running time) in Chinese cabbage and cucumber. Samples were extracted with a quick, easy, cheap, effective, rugged, and safe (QuECHERS) preparation method and cleanup with different sorbents, including primary secondary amine (PSA), multi-walled carbon nanotubes (MWCNTs), and polystyrene (PLS), to find out the most suitable cleanup methods for Chinese cabbage and cucumber. The recovery and matrix effect were evaluated by monitoring the main parameters in one group of 238 pesticides at the spiked level of 8 and 40 ?g/kg. In Chinese cabbage, when PSA dispersive solid-phase extraction (D-SPE) was applied, recoveries of 183 pesticides ranged between 70 and 120% with relative standard deviation (RSD) values lower than 20% at a spiked level of 40 ?g/kg, indicating the effectiveness of the purification step. In cucumber, 203 pesticides were in the 70-120% recovery range with good reproducibility by PSA mini-cartridge column cleanup at a spiked level of 40 ?g/kg and RSD values were generally below 20%. The limits of quantitation [LOQs; signal-to-noise (S/N) = 10] were in the range of 0.16-10.20 ?g/kg for Chinese cabbage and 0.06-21.06 ?g/kg for cucumber, while the limits of detection (LODs; S/N = 3) were between 0.05 and 3.06 ?g/kg and between 0.02 and 6.32 ?g/kg in Chinese cabbage and cucumber, respectively. The proposed methods that might be applied for the multi-residue analysis in Chinese cabbage and cucumber are contributed to their rapid speed and good recoveries.
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Design, construction, and testing of solution resistive divider applied in hundreds of kilovolts nanosecond pulse measurement.
Rev Sci Instrum
PUBLISHED: 11-03-2014
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The solution resistive divider is often used considering its excellent high-frequency and withstanding voltage characteristics. This paper develops a nanosecond pulse measurement system based on the CuSO4 solution resistive divider, which can be used to measure high voltage impulses with rise time of 50 ns and amplitude of 300 kV. The low-voltage arm of the newly designed solution resistive divider is composed of noninductive metal film resistors. The newly designed resistive divider combines the advantages of the conventional solution resistive divider and metal film resistive divider. The stray parameters of the resistive divider are theoretically calculated and the circuit simulation is studied. Besides, the square wave response characteristics of the resistive divider are studied in the experiments. Considering the effect of frequency on the surge impedance of the cable, a matching cable of the same type with the transmission cable instead of a common matching resistor is used to improve the matching effects. In order to reduce the effects of electromagnetic interference on the measurement results, some shielding measures are taken. The experimental results show that the measurement system has good response characteristics in the practical application.
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A Novel Total Cervical Prosthesis for Single-level Cervical Subtotal Corpectomy: Radiological and Histomorphometric Analysis in a Caprine Model.
J Spinal Disord Tech
PUBLISHED: 10-30-2014
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A novel total cervical prosthesis for single level cervical subtotal corpectomy was assessed in a caprine animal model.
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Metabolomics in dyslipidemia.
Adv Clin Chem
PUBLISHED: 10-28-2014
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Hyperlipidemia is an important public health problem with increased incidence and prevalence worldwide. Current clinical biomarkers, triglyceride, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol lack the necessary specificity and sensitivity and only increase significantly after serious dyslipidemia. Therefore, sensitive biomarkers are needed for hyperlipidemia. Hyperlipidemia-specific biomarkers would improve clinical diagnosis and therapeutic treatment at early disease stages. The aim of metabolomics is to identify untargeted and global small-molecule metabolite profiles from cells, biofluids, and tissues. This method offers the potential for a holistic approach to improve disease diagnoses and our understanding of underlying pathologic mechanisms. This review summarizes analytical techniques, data collection and analysis for metabolomics, and metabolomics in hyperlipidemia animal models and clinical studies. Mechanisms of hypolipemia and antilipemic drug therapy are also discussed. Metabolomics provides a new opportunity to gain insight into metabolic profiling and pathophysiologic mechanisms of hyperlipidemia.
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[Influencing factors of sludge liquor treatment in UASBB].
Huan Jing Ke Xue
PUBLISHED: 10-24-2014
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The effect of ammonia nitrogen concentration, temperature, pH, HRT and C/N ratio on ANAMMOX was studied. The reactor was fed with sludge liquor. The efficiency of nitrogen removal for the UASBB was researched under different ammonia nitrogen concentration, HRT, temperature, pH and C/N ratio when the influent rho(NH4(+) -N)/rho(NO2(-) -N) was controlled at 1:1.32. The results showed that the nitrogen removal rate for the ANANMMOX reactors was optimal when the influent NH4(+) -N and NO2(-) -N concentrations were 200 mg x L(-1) and 264 mg x L(-1), HRT was 24 h, temperature was in the range of 30-35 degrees C, pH was at 7.5-8.5 and the C/N ratio was 0.5. The average removal rates of NH4(+) -N, NO2(-) -N and TN were 75.72%, 76.36% and 70.19%, respectivley, the average TN was 0.464 kg x (m3 x d)(-1) and the removal rate of COD was 30%. The efficiency of nitrogen removal for the ANAMMOX reactors could be enhanced by controlling ammonia nitrogen concentration and HRT. The efficiency of ANAMMOX bacteria was optimal when temperature and pH were suitable. The denitrification occurred in the ANAMMOX reactors when the influent contained organics. The inhibition of denitrification bacteria on the ANAMMOX increased with rising concentration of organics.
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Anti-hepatitis B virus activities and absolute configurations of sesquiterpenoid glycosides from Phyllanthus emblica.
Org. Biomol. Chem.
PUBLISHED: 10-01-2014
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During the process exploring anti-viral compounds from Phyllanthus species, eight new highly oxygenated bisabolane sesquiterpenoid glycoside phyllaemblicins G1-G8 () were isolated from Phyllanthus emblica, along with three known compounds, phyllaemblicin F (), phyllaemblic acid () and glochicoccin D (). Phyllaemblicin G2 (), bearing a tricyclo [3.1.1.1] oxygen bridge ring system, is an unusual sesquiterpenoid glycoside, while phyllaemblicins G6-G8 () are dimeric sesquiterpenoid glycosides with two norbisabolane units connecting through a disaccharide. All the structures were elucidated by the extensive analysis of HRMS and NMR data. The relative configuration of phyllaemblicin G2 was constructed based on heteronuclear coupling constants measurement, and the absolute configurations for all new compounds were established by calculated electronic circular dichroism (ECD) using time dependent density functional theory. The sesquiterpenoid glycoside dimers displayed potential anti-hepatitis B virus (HBV) activities, especially for the new compound with IC50 of 8.53 ± 0.97 and 5.68 ± 1.75 ?M towards the HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively.
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rs10865331 associated with susceptibility and disease severity of ankylosing spondylitis in a Taiwanese population.
PLoS ONE
PUBLISHED: 09-03-2014
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Ankylosing spondylitis (AS) is a highly familial rheumatic disorder and is considered as a chronic inflammatory disease. Genetic factors are involved in the pathogenesis of AS. To identify genes which render people susceptible to AS in a Taiwanese population, we selected six single-nucleotide polymorphisms (SNPs) from previous genome-wide association studies (GWASs) which were associated with AS in European descendants and Han Chinese. To assess whether the six SNPs contributed to AS susceptibility and severity in Taiwanese population, 475 AS patients fulfilling the modified New York Criteria and 527 healthy subjects were recruited. We found that rs10865331 was significantly associated with AS susceptibility and with Bath AS Function Index (BASFI). The AA and AG genotypes of rs10865331 were also significantly associated with a higher erythrocyte sedimentation rate. Our findings provided evidence that rs10865331 is associated AS susceptibility and with disease activity (BASFI) in a Taiwanese population.
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Evidence of topological surface state in three-dimensional Dirac semimetal Cd3As2.
Sci Rep
PUBLISHED: 08-20-2014
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The three-dimensional topological semimetals represent a new quantum state of matter. Distinct from the surface state in the topological insulators that exhibits linear dispersion in two-dimensional momentum plane, the three-dimensional semimetals host bulk band dispersions linearly along all directions. In addition to the gapless points in the bulk, the three-dimensional Weyl/Dirac semimetals are also characterized by "topologically protected" surface state with Fermi arcs on their surface. While Cd3As2 is proposed to be a viable candidate of a Dirac semimetal, more investigations are necessary to pin down its nature. In particular, the topological surface state, the hallmark of the three-dimensional semimetal, has not been observed in Cd3As2. Here we report the electronic structure of Cd3As2 investigated by angle-resolved photoemission measurements on the (112) crystal surface and detailed band structure calculations. The measured Fermi surface and band structure show a good agreement with the band structure calculations with two bulk Dirac-like bands approaching the Fermi level and forming Dirac points near the Brillouin zone center. Moreover, the topological surface state with a linear dispersion approaching the Fermi level is identified for the first time. These results provide experimental indications on the nature of topologically non-trivial three-dimensional Dirac cones in Cd3As2.
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Potential effects of large linear pipeline construction on soil and vegetation in ecologically fragile regions.
Environ Monit Assess
PUBLISHED: 08-12-2014
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Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant community. During the recovery period, the plant community in the work area of the pipeline is replaced by some species that are rare or uncommon in the resident plant community because of human disturbance, thereby increasing the plant diversity in the work area. In terms of plant succession, the duration of the recovery period has a direct effect on the composition and structure of the plant community. The findings provide a theoretical basis and scientific foundation for improving the environmental impact assessment (EIA) of oil and gas pipeline construction as it pertains to the desert steppe ecosystem, and provide a reference point for recovery and management of the eco-environment during the pipeline construction period.
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Rosiglitazone attenuates cerebral vasospasm and provides neuroprotection in an experimental rat model of subarachnoid hemorrhage.
Neurocrit Care
PUBLISHED: 07-16-2014
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Glutamate and oxidative stress play important roles after subarachnoid hemorrhage (SAH). The ability to modulate glutamate transporter 1 (GLT-1) and the antioxidative effect of rosiglitazone have been demonstrated. We investigated the neuroprotective effect of rosiglitazone after SAH.
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Osseointegration of chitosan coated porous titanium alloy implant by reactive oxygen species-mediated activation of the PI3K/AKT pathway under diabetic conditions.
Biomaterials
PUBLISHED: 07-03-2014
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Chitosan coated porous titanium alloy implant (CTI) is demonstrated a promising approach to improve osseointegration capacity of pure porous titanium alloy implant (TI). Since chitosan has been demonstrated to exhibit antioxidant activity, we propose CTI may ameliorate the ROS overproduction, thus reverse the poor osseointegration under diabetic conditions, and investigate the underlying mechanisms. Primary rat osteoblasts incubated on the TI and the CTI were subjected to normal serum (NS), diabetic serum (DS), DS + NAC (a potent ROS inhibitor) and DS + LY294002 (a PI3K/AKT-specific inhibitor). In vivo study was performed on diabetic sheep implanted with TI or CTI into the bone defects on crista iliaca. Results showed that diabetes-induced ROS overproduction led to osteoblast dysfunction and apoptosis, concomitant with the inhibition of AKT in osteoblasts on the TI substrate. While CTI stimulated AKT phosphorylation through ROS attenuation, thus reversed osteoblast dysfunction evidenced by improved osteoblast adhesion, increased proliferation and ALP activity, and decreased cytotoxicity and apoptotic rate, which exerted same effect to NAC treatment on the TI. These effects were further confirmed by the improved osseointegration within the CTI in vivo evidenced by Micro-CT and histological examinations. In addition, the aforementioned promotive effects afforded by CTI were abolished by blocking PI3K/AKT pathway with addition of LY294002. These results demonstrate that the chitosan coating markedly ameliorates diabetes-induced impaired bio-performance of TI via ROS-mediated reactivation of PI3K/AKT pathway, which elicits a new surface functionalization strategy for better clinical performance of titanium implant in diabetic patients.
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A new sesquiterpene lactone from the fruits of Illicium henryi.
Chin J Nat Med
PUBLISHED: 06-28-2014
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To study the chemical constituents of the fruits of Illicium henryi.
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Transcriptome analysis reveals positive selection on the divergent between topmouth culter and zebrafish.
Gene
PUBLISHED: 06-17-2014
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The topmouth culter (Erythroculter ilishaeformis) is a predatory cyprinid fish that distributes widely in the East Asia. Here we report the liver transcriptome in this organism as a model of predatory fish. Sequencing of 5Gb raw reads led to 27,741 unigenes and produced 11,131 annotatable genes. A total of 7093 (63.7%) genes were found to have putative functions by gene ontology analysis. Importantly, a blast search revealed 4033 culter genes that were orthologous to the zebrafish. Extracted from 38 candidate positive selection genes, 4 genes exhibit strong positive selection based on the ratio of nonsynonymous (Ka) to synonymous substitutions (Ks). In addition, the four genes also indicated the strong positive selection by comparing them between blunt snout bream (Megalobrama amblycephala) and zebrafish. These genes were involved in activator of gene expression, metabolic processes and development. The transcriptome variation may be reflective of natural selection in the early life history of Cyprinidae. Based on Ks ratios, date of the separation between topmouth culter and zebrafish is approximately 64millionyears ago. We conclude that natural selection acts in diversifying the genomes between topmouth culter and zebrafish.
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GATA-4 protects against hypoxia-induced cardiomyocyte injury: effects on mitochondrial membrane potential.
Can. J. Physiol. Pharmacol.
PUBLISHED: 06-11-2014
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Our previous studies have suggested that GATA-4 increases the differentiation of bone-marrow-derived mesenchymal stem cells (MSCs) into cardiac phenotypes. This study further investigated whether GATA-4 enhances MSC-mediated cardioprotection following hypoxia. MSCs were harvested from rat bone marrow and transduced with GATA-4 (MSC(GATA-4)). To mimic ischemic injury, cultured cardiomyocytes (CMs) isolated from neonatal rat ventricles were exposed to hypoxia or were pretreated with concentrated conditioned medium (CdM) from MSC(GATA-4) or transduced control MSC (MSC(Null)) for 16 h before exposure to hypoxic culture conditions (low glucose and low oxygen). Myocyte damage was estimated by annexin-V-PE and TUNEL technique and by lactate dehydrogenase (LDH) release. Cell survival was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium (MTT) uptake. Mitochondrial membrane potential was determined using confocal microscopy. ELISA studies indicated that insulin-like growth factor?1 (IGF-1) and vascular endothelial growth factor (VEGF) were significantly increased in MSC(GATA-4) compared with MSC(Null). Hypoxia-induced apoptosis/cell death was significantly reduced when CMs were co-cultured with MSC(GATA-4) in a dual-chamber system. Cell protection mediated by MSC(GATA-4) was mimicked by treating CMs with CdM from MSC(GATA-4) and abrogated with IGF-1- and VEGF-neutralizing antibodies. MSC(GATA-4) protects CMs under hypoxic conditions. The release of IGF-1 and VEGF from MSC(GATA-4) is likely to be responsible for protection of CMs.
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Topological analysis of the three-dimensional coordination polymer poly[(?4-azido)[?4-5-(pyridin-4-yl)tetrazolido]disilver(I)].
Acta Crystallogr C Struct Chem
PUBLISHED: 06-01-2014
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The title compound, [Ag2(C6H4N4)(N3)]n, was obtained under hydrothermal conditions at 433?K. The asymmetric unit of the orthorhombic space group (Pna21) consists of two Ag(+) cations, an anionic 5-(pyridin-4-yl)tetrazolide (4-ptz(-)) ligand and an anionic azide ligand. Both Ag(+) centres are coordinated by four N atoms, forming a distorted tetrahedral coordination environment. When all the component ions are viewed as 4-connected nodes, the whole three-dimensional network can be regarded topologically as a new kind of 4,4,4,4-connected net with the Schläfli symbol (4.8(5))(4(2).8(4))(4(3).8(3))2.
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Anti-hepatitis B virus norbisabolane sesquiterpenoids from Phyllanthus acidus and the establishment of their absolute configurations using theoretical calculations.
J. Org. Chem.
PUBLISHED: 05-28-2014
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Nineteen new highly oxygenated norbisabolane sesquiterpenoids, phyllanthacidoid acid methyl ester (1), and C-T (4-21), were isolated from Phyllanthus acidus Skeels, together with two known ones, phyllanthusols A (2) and B (3), whose sugar moiety was revised as glucosamine-N-acetate, rather than the previously assigned mannosamine-N-acetate. Compounds 2 and 3 were renamed respectively as phyllanthacidoids A (2) and B (3) to avoid confusion. All of the isolates except for 1 are glycosides, whose saccharide moieties possess a pentaoxy cyclohexane (scyllo quercitol) connecting with glucosamine-N-acetate or glucosyl moieties, which are first examples in natural products. Phyllanthacidoids N-R (15-19) with 8R configurations and/or 5,8-diketal skeleton, are unprecedented structures among norbisabolane sesquiterpenoids. Phyllanthacidoids S (20) and T (21) have the unusual tricyclo [3.1.1.1] oxygen bridge skeleton formed by a diketal system, of which the relative configurations of the aliphatic chain were assigned on the basis of heteronuclear coupling constants. The absolute configurations of compounds (1-21) were established by means of calculated electronic circular dichroism (ECD) and coupling constants. Compounds 1-5, 7-9, 10, and 14 displayed potential anti-hepatitis B virus (HBV) activities, with IC50 values of 0.8-36 ?M against HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg), and the results indicated that the 5-ketal group and sugar moieties had contributions to the selectivity of HBsAg and HBeAg.
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Preventive effect of crocin on osteoporosis in an ovariectomized rat model.
Evid Based Complement Alternat Med
PUBLISHED: 05-20-2014
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The purpose of this study was to investigate the therapeutic effects of crocin on ovariectomy-induced osteoporosis in rats. Female Sprague-Dawley rats were randomly assigned to a sham-operated group (sham) and five ovariectomy (OVX) subgroups, that is, OVX with vehicle (OVX), OVX with 17?-estradiol (E 2, 25??g/kg/day), and OVX with graded crocin doses (5, 10, or 20?mg/kg/day). Daily oral administration of E 2 or crocin started 4 weeks after OVX and lasted for 16 weeks. Our results showed that crocin dose-dependently inhibited the BMD reduction of L4 vertebrae and femurs caused by OVX and prevented the deterioration of trabecular microarchitecture, which were accompanied by a significant decrease in skeletal remodeling as evidenced by the lower levels of bone turnover markers. Furthermore, crocin reversed the oxidative stress status in both serum and bone tissue. The present study indicates that the administration of crocin at higher doses over a 16-week period can prevent OVX-induced osteoporosis in rats without hyperplastic effects on the uterus, which may, at least partially, be attributed to crocin's antioxidative property. In brief, crocin is a natural alternative for postmenopausal osteoporosis treatment in elderly women.
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Multiresidue method for the determination of 227 pesticides in hot pepper (Capsicum annuum L.) by liquid chromatography with tandem mass spectrometry†.
J Sep Sci
PUBLISHED: 05-20-2014
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A high-throughput, rapid, and efficient modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with a simple cleanup procedure has been developed for simultaneously determining 227 pesticides in pepper samples by liquid chromatography with tandem mass spectrometry (running time: 10 min). Pesticide residues were extracted/partitioned with an acetonitrile/DisQuE QuEChERS pouch, and the resulting samples were cleaned up with different methods: dispersive solid-phase extraction with primary secondary amines or multiwalled carbon nanotubes and graphitized carbon solid mini cartridge column. The results indicated that multiwalled carbon nanotubes dispersive sorbents achieved the best recoveries and had less matrix interference. The numbers of pesticides with a recovery in the range of 70-120% were 199 at a spiked level of 40 ?g/kg. The correlation coefficients (r(2) ) for 227 pesticides were above 0.99, while the limits of quantitation of pesticides in pepper samples ranged from 0.13 to 13.51 ?g/kg (S/N = 10), and the limits of detection ranged from 0.04 to 4.05 ?g/kg (S/N = 3). The relative standard deviations of approximately 197 pesticides were below 20% at spiked levels of 40 ?g/kg. Based on these results, the proposed method was chosen as the most suitable cleanup procedure for the determination of multiresidue pesticides in pepper samples.
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[Responses of net soil nitrogen mineralization rate in moss-covered soil to hydrothermic factors in Shapotou regions, northern China].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 05-17-2014
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Undisturbed soil cores were incubated in laboratory at different temperatures (-10, 5, 15, 25, 35 and 40 degrees C) and moistures (29%, 58%, 85% and 170% of field water content, FWC) to analyze the effect of moss crusts, which were sampled from the natural vegetation area of Shapotou, on soil nitrogen transformation and their responses to hydrothermic factors. Results showed that immobilization was the dominant form of nitrogen transformation at the lower temperatures (<15 degrees C), and when the temperature surpassed 25 degrees C, the nitrogen transformation rate significantly increased. The nitrogen transformation rate in the moss-covered soil was more sensitive to temperature variation than in the bare soil, and the highest temperature sensitivity was at 85% FWC. It indicated that the existence and succession of moss crusts facilitated nitrogen transformation. In addition, the nitrogen transformation rates of two microhabitats increased initially and then declined with the increasing moisture, and the maximum nitrogen transformation rate was observed at 85% FWC. Significant interactive effects were found between temperature and moisture in the moss-covered soil. While, the greater enhancement in nitrogen transformation rate appeared at higher temperatures (25-40 degrees C ) and moderate moisture levels (58% FWC and 85% FWC). It was concluded that the existence and succession of moss crusts would increase the ability of soil nitrogen supply, promote nitrogen cycling and even contribute to the restoration of soil ecosystem.
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Insulin improves osteogenesis of titanium implants under diabetic conditions by inhibiting reactive oxygen species overproduction via the PI3K-Akt pathway.
Biochimie
PUBLISHED: 05-13-2014
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Clinical evidence indicates that insulin therapy improves implant survival rates in diabetic patients; however, the mechanisms responsible for this effect are unknown. Here, we test if insulin exerts anti-oxidative effects, thereby improving diabetes-associated impaired osteoblast behavior on titanium implants. To test this hypothesis, we cultured primary rabbit osteoblasts in the presence of titanium implants and studied the impact of treatment with normal serum (NS), diabetic serum (DS), DS + insulin, DS + tempol (a superoxide dismutase mimetic), DS + insulin + tempol, and DS + insulin + wortmannin. We analyzed cell function, apoptosis, and reactive oxygen species (ROS) production in osteoblasts following the various treatments. Treatment with DS induced osteoblast dysfunction, evidenced by impaired cell attachment and morphology, decreased cell proliferation and ALP activity, and decreased expression of osteogenesis-related genes. We also observed a significant increase in apoptosis. Importantly, treatment with DS resulted in increased production of ROS in osteoblasts. In contrast, treatment with insulin inhibited ROS production, alleviated cell dysfunction, and decreased apoptosis of osteoblasts on the implants. Scavenging ROS with tempol also attenuated cell dysfunction. Compared to insulin treatment alone, the combination of insulin and tempol failed to further improve osteoblast functional recovery. Moreover, the anti-oxidative and pro-osteogenic effects afforded by insulin were almost completely abolished by the phosphatidylinositol 3-kinase (PI3K) inhibitor wortmannin. These results demonstrate, for the first time, that insulin treatment alleviates the impaired osteogenesis of titanium implants under diabetic conditions by inhibiting ROS overproduction via a PI3K/Akt-dependent mechanism. Both the anti-oxidative and metabolic properties of insulin should make it a viable therapeutic option to combat diabetic implant failure.
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An SPE-assisted BODIPY fluorometric paper sensor for the highly selective and sensitive determination of Cd²? in complex sample: rice.
Analyst
PUBLISHED: 05-07-2014
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By using sensing technology, the individual component analysis at trace level in complex samples remains problematic simply because of various interfering species. For example, the determination of Cd(2+) in rice is difficult due to the co-existing interfering metal cations at thousands or even millions of times higher concentrations. In this study, a heavy-metal ion sensitive BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene)-based fluorometric paper sensor with assistance of solid phase extraction (SPE) was developed for the highly selective and sensitive determination of trace Cd(2+) in rice. SPE column packed with prepared sulfonated PS-DVB microspheres was employed to enrich trace Cd(2+) and meanwhile remove most interfering heavy-metal ions in simulated complex rice sample with oxalic acid as eluent, which was theoretically selected on the basis of f values. Mn(2+), as a major coexistent heavy-metal ion, could not be easily removed by SPE, but showed little fluorescent response for BODIPY fluorometric paper sensor even in excess amounts. Combining the separation and enrichment capability of SPE column with the selectivity of BODIPY-based fluorometric paper sensor, we were able to detect trace Cd(2+) in complex samples. The response of fluorometric paper sensor was linearly related with Cd(2+) concentrations in the range of 0.5-4 ?M, with a detection limit of 0.5 ?M. Twelve real rice samples spiked with Cd(2+) were analysed using this method and the results are in good agreement with ICP-MS measurements.
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Incidence and risk factors for the prozone phenomenon in serologic testing for syphilis in a large cohort.
Clin. Infect. Dis.
PUBLISHED: 05-06-2014
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The prozone phenomenon is known to be associated with high antibody titers; other associations, such as host factors, have not been elucidated.
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Neuroprotection by Orexin-A via HIF-1? induction in a cellular model of Parkinson's disease.
Neurosci. Lett.
PUBLISHED: 04-30-2014
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Orexin-A, a neuropeptide secreted by hypothalamic neurons, may be neuroprotective in many neurological conditions such as cerebral ischaemia. One mechanism postulated to be involved in the neuroprotection by Orexin-A is the induction of hypoxia inducible factor 1 alpha (HIF-1?). Parkinson's disease (PD) is a progressive neurodegenerative disorder and mitochondrial dysfunction has been demonstrated to play a role in its pathogenesis. Mitochondrial dysfunction may cause reduction of O2 consumption and subsequently activate prolyl hydroxylase, which leads to decreased level of HIF-1?. In this study, we used MPP(+)-treated SH-SY5Y cells as an in vitro cellular model of PD to test the role of Orexin-A as an inducer of HIF-1?. Our results showed that Orexin-A not only induced HIF-1? but also activated downstream targets of HIF-1?, such as vascular endothelial growth factor and erythropoietin. Thus, Orexin-A treatment attenuated MPP(+)-induced cell injury and this effect was blocked when HIF-1? was suppressed. Hence, we conclude that induction of HIF-1? is one of the mechanisms involved in the neuroprotection by Orexin-A.
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[Efficacy of combination therapy of tamsulosin and solifenacin for mild and moderate benign prostatic hyperplasia with overactive bladder].
Zhonghua Nan Ke Xue
PUBLISHED: 04-18-2014
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To evaluate the efficacy and safety of the combination therapy of tamsulosin and solifenacin for mild and moderate benign prostatic hyperplesia (BPH) with overactive bladder (OAB).
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Small kernel 1 encodes a pentatricopeptide repeat protein required for mitochondrial nad7 transcript editing and seed development in maize (Zea mays) and rice (Oryza sativa).
Plant J.
PUBLISHED: 04-16-2014
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RNA editing modifies cytidines (C) to uridines (U) at specific sites in the transcripts of mitochondria and plastids, altering the amino acid specified by the DNA sequence. Here we report the identification of a critical editing factor of mitochondrial nad7 transcript via molecular characterization of a small kernel 1 (smk1) mutant in Zea mays (maize). Mutations in Smk1 arrest both the embryo and endosperm development. Cloning of Smk1 indicates that it encodes an E-subclass pentatricopeptide repeat (PPR) protein that is targeted to mitochondria. Loss of SMK1 function abolishes the C ? U editing at the nad7-836 site, leading to the retention of a proline codon that is edited to encode leucine in the wild type. The smk1 mutant showed dramatically reduced complex-I assembly and NADH dehydrogenase activity, and abnormal biogenesis of the mitochondria. Analysis of the ortholog in Oryza sativa (rice) reveals that rice SMK1 has a conserved function in C ? U editing of the mitochondrial nad7-836 site. T-DNA knock-out mutants showed abnormal embryo and endosperm development, resulting in embryo or seedling lethality. The leucine at NAD7-279 is highly conserved from bacteria to flowering plants, and analysis of genome sequences from many plants revealed a molecular coevolution between the requirement for C ? U editing at this site and the existence of an SMK1 homolog. These results demonstrate that Smk1 encodes a PPR-E protein that is required for nad7-836 editing, and this editing is critical to NAD7 function in complex-I assembly in mitochondria, and hence to embryo and endosperm development in maize and rice.
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Diuretic and anti-diuretic activities of fractions of Alismatis rhizoma.
J Ethnopharmacol
PUBLISHED: 04-12-2014
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Alismatis rhizoma or Alisma orientale (Zexie in Chinese), the dried rhizome of Alisma orientale Juzepzuk (Alismataceae), is a well-known traditional Chinese medicine and is used as an agent for diuresis and for excreting dampness in China and Japan. In this paper, we report the diuretic activities of the petroleum ether fraction, the ethyl acetate fraction, the n-buthanol fraction, and the remaining fraction, of the ethanol extract of Alismatis rhizoma (AR).
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The promotion of osteointegration under diabetic conditions using chitosan/hydroxyapatite composite coating on porous titanium surfaces.
Biomaterials
PUBLISHED: 04-01-2014
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Composited Chitosan/Hydroxyapatite (CS/HA) material coated on titanium surface (cTi) is a promising approach to produce biomaterials with better osseointegration capacity, but its bio-performance under diabetic conditions and the mechanisms involved remain elusive. We propose that the alterations in the Wnt/?-catenin pathway may play a role in mediating the improvement effect of cTi on diabetes-induced impaired implant osteointegration. To confirm the hypothesis, primary rat osteoblasts incubated on Ti and cTi were subjected to normal serum (NS), diabetic serum (DS), DS + Wnt3a (a specific Wnt agonist) and DS + Dkk1 (a specific Wnt antagonist) treatment. In vivo study was performed on diabetic sheep implanted with Ti or cTi into the bone defect on crista iliaca. Results showed that diabetes depressed osteoblast function evidenced by impaired cell adhesion and morphology, decreased cell proliferation and ALP activity, and higher apoptotic rate on Ti. Importantly, both cTi and Wnt3a treatment ameliorated osteoblastic dysfunction and apoptosis under diabetic condition. Implantation with cTi significantly improved osteointegration evidenced by Micro-CT and histological examinations compared with Ti. Moreover, the aforementioned promotive effects afforded by cTi were abolished by blocking Wnt pathway with Dkk1. Our study explicitly demonstrates that CS/HA composite material improves diabetes-induced impaired osteointegration of Ti via the reactivation of Wnt/?-catenin pathway and provides a target point for biomaterial modification to attain better clinical performance in diabetic patients.
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[Expression of miR-16 in patients with T lymphoblastic lymphoma/acute lymphoblastic leukemia].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 03-07-2014
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This study was purposed to investigate the expression of miR-16 in T lymphoblastic lymphoma/acute lymphoblastic leukemia (T-LBL/ALL) and its relation with target therapy and prognosis. The CD3, cCD3, CD10, CD20, CD34, CD43, CD99, TdT, PAX-5, BCL-2 and Ki67 in paraffin samples from 38 cases of T-LBL/ALL were detected by immunohistochemical labeling; the miR-16 expression level was detected by real-time RT-PCR. Fifteen cases of reactive hyperplasia of lymph nodes were selected as control. The results indicated that among 38 cases of T-LBL/ALL the positive rate of TdT was highest (94.7%), the positive rate of CD34 was lowest (22.1%), the PAX-5 and CD20 were found to be negative. The Ki67 expression level in 39.5% cases exceeded 80%. As compared with reactive hyperplasia of lymph node, the miR-16 expression in T-LBL/ALL was up-regulated, ant its expression level was 4.87-fold of reactive hyperplasia of lymph node (P < 0.05). The overall survival rate in group of miR-16 high expression decreased (P < 0.05). The prognosis of T-LBL/ALL patients with BCL-2 positive expression was better than that of patients with BCL-2 negative expression (P < 0.05). The miR-16 expression correlated with BCL-2 protein (r = 0.51, P < 0.05). It is concluded that the overall survival rate in miR-16 high expression group is higher than that in miR-16 low expression group, suggesting possible relation of miR-16 with prognosis. Moreover, the prognosis in BCL-2 positive expression group is better than that in negative expression group, which may be a factor influencing prognosis.
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Protective role of hydrogen-rich water on aspirin-induced gastric mucosal damage in rats.
World J. Gastroenterol.
PUBLISHED: 03-04-2014
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To investigate the role of the hydrogen-rich water (HRW) in the prevention of aspirin-induced gastric mucosal injury in rats.
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Diuretic and anti-diuretic activities of the ethanol and aqueous extracts of Alismatis rhizoma.
J Ethnopharmacol
PUBLISHED: 02-24-2014
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Alismatis rhizoma or Alisma orientale (Zexie in Chinese), the dried rhizome of Alisma orientale Juzepzuk (Alismataceae), is a well-known traditional Chinese medicine and is used as an agent for diuresis and for excreting dampness in Asia and Europe. In this paper, we report the diuretic activities of the ethanol extract (EE) and the aqueous extract (AE) of A. rhizoma (AR).
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Analysis of 3 algorithms for syphilis serodiagnosis and implications for clinical management.
Clin. Infect. Dis.
PUBLISHED: 02-18-2014
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Algorithms for the diagnosis of syphilis continue to be a source of great controversy, and numerous test interpretations have perplexed many clinicians.
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Down-regulation of FoxM1 inhibits viability and invasion of gallbladder carcinoma cells, partially dependent on inducement of cellular senescence.
World J. Gastroenterol.
PUBLISHED: 02-14-2014
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To investigate the effect of knockdown of Forkhead box M1 (FoxM1) on the proliferation and invasion capacities of human gallbladder carcinoma (GBC)-SD cells.
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GATA-4 induces changes in electrophysiological properties of rat mesenchymal stem cells.
Biochim. Biophys. Acta
PUBLISHED: 02-14-2014
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Transplanted mesenchymal stem cells (MSC) can differentiate into cardiac cells that have the potential to contribute to heart repair following ischemic injury. Overexpression of GATA-4 can significantly increase differentiation of MSC into cardiomyocytes (CM). However, the specific impact of GATA-4 overexpression on the electrophysiological properties of MSC-derived CM has not been well documented.
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Strong anisotropy of Dirac cones in SrMnBi2 and CaMnBi2 revealed by angle-resolved photoemission spectroscopy.
Sci Rep
PUBLISHED: 02-11-2014
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The Dirac materials, such as graphene and three-dimensional topological insulators, have attracted much attention because they exhibit novel quantum phenomena with their low energy electrons governed by the relativistic Dirac equations. One particular interest is to generate Dirac cone anisotropy so that the electrons can propagate differently from one direction to the other, creating an additional tunability for new properties and applications. While various theoretical approaches have been proposed to make the isotropic Dirac cones of graphene into anisotropic ones, it has not yet been met with success. There are also some theoretical predictions and/or experimental indications of anisotropic Dirac cone in novel topological insulators and AMnBi2 (A = Sr and Ca) but more experimental investigations are needed. Here we report systematic high resolution angle-resolved photoemission measurements that have provided direct evidence on the existence of strongly anisotropic Dirac cones in SrMnBi2 and CaMnBi2. Distinct behaviors of the Dirac cones between SrMnBi2 and CaMnBi2 are also observed. These results have provided important information on the strong anisotropy of the Dirac cones in AMnBi2 system that can be governed by the spin-orbital coupling and the local environment surrounding the Bi square net.
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Orbital-selective spin texture and its manipulation in a topological insulator.
Nat Commun
PUBLISHED: 02-05-2014
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Topological insulators represent a new quantum state of matter that are insulating in the bulk but metallic on the edge or surface. In the Dirac surface state, it is well-established that the electron spin is locked with the crystal momentum. Here we report a new phenomenon of the spin texture locking with the orbital texture in a topological insulator Bi?Se?. We observe light-polarization-dependent spin texture of both the upper and lower Dirac cones that constitutes strong evidence of the orbital-dependent spin texture in Bi?Se?. The different spin texture detected in variable polarization geometry is the manifestation of the spin-orbital texture in the initial state combined with the photoemission matrix element effects. Our observations provide a new orbital degree of freedom and a new way of light manipulation in controlling the spin structure of the topological insulators that are important for their future applications in spin-related technologies.
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Model based on ?-glutamyltransferase and alkaline phosphatase for hepatocellular carcinoma prognosis.
World J. Gastroenterol.
PUBLISHED: 01-24-2014
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To determine the prognostic value of alkaline phosphatase (ALP) and ?-glutamyltransferase (GGT) for hepatocellular carcinoma (HCC) .
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Characterization of the classical biological false-positive reaction in the serological test for syphilis in the modern era.
Int. Immunopharmacol.
PUBLISHED: 01-17-2014
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To characterize the CBFP reaction in the modern era, we analyzed the results of parallel rapid plasma reagin (RPR) and Treponema pallidum particle agglutination (TPPA) tests from a total of 63,765 blood samples obtained at Zhongshan Hospital in the Medical College of Xiamen University from May 2008 to February 2013. Among the 63,765 tested blood samples, 206 (0.32%) had the CBFP reaction. In multivariate analysis, an increased likelihood of the CBFP reaction was associated with female subjects, subjects ?80years old, and subjects between 16 and 35years old (P<0.05). The CBFP reaction occurred in association with 17 categories of disease, including 60 types of diseases, in the 206 subjects. To our knowledge, a number of these diseases had not been previously reported to be associated with the CBFP in the RPR test, including false labor, megaloblastic anemias, aplastic anemias, redundant prepuce, congenital malformation of heart, and salpingitis. Among the 206 patients with the CBFP reaction, 35 patients were subjected to follow-up for five years. 26 out of 35 these patients were at a 1:1 initial RPR titer, 8 out of 35 patients were at a 1:2 initial RPR titer, and 1 out of 35 patients were at a 1:4 initial RPR titer. 30 subjects had their RPR seroreverted. In our opinion, additional CBFP research using a large sample population will contribute to the identification of additional underlying serious disorders that are not related to syphilis. Such results could be useful for the prediction and diagnosis of these diseases.
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Biomechanical comparison of osteoporotic distal radius fractures fixed by distal locking screws with different length.
PLoS ONE
PUBLISHED: 01-01-2014
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To evaluate the postoperative stability of osteoporotic distal radius fractures fixed with distal locking screws with different length.
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Repair of segmental bone defect using Totally Vitalized tissue engineered bone graft by a combined perfusion seeding and culture system.
PLoS ONE
PUBLISHED: 01-01-2014
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The basic strategy to construct tissue engineered bone graft (TEBG) is to combine osteoblastic cells with three dimensional (3D) scaffold. Based on this strategy, we proposed the "Totally Vitalized TEBG" (TV-TEBG) which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect.
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Systemic treatment with telmisartan improves femur fracture healing in mice.
PLoS ONE
PUBLISHED: 01-01-2014
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Recent clinical studies indicated that angiotensin receptor blockers (ARBs) would decrease the risk of bone fractures in the elderly populations. There is little known about the role of the ARBs in the process of fracture healing. The purpose of the present study was to verify the hypothesis that systemic treatment with telmisartan has the ability to promote fracture healing. In this study, femur fractures were produced in 96 mature male BALB/c mice. Animals were treated with the ARBs telmisartan or vehicle. Fracture healing was analysed after 2, 5 and 10 weeks postoperatively using X-ray, biomechanical testing, histomorphometry, immunohistochemistry and micro-computed tomography (micro-CT). Radiological analysis showed the diameter of the callus in the telmisartan treated animals was significantly increased when compared with that of vehicle treated controls after two weeks of fracture healing. The radiologically observed promotion of callus formation was confirmed by histomorphometric analyses, which revealed a significantly increased amount of bone formation when compared with vehicle-treated controls. Biomechanical testing further showed a significantly greater peak torque at failure, and a higher torsional stiffness in telmisartan-treated animals compared with controls. There was an increased fraction of PCNA-positive cells and VEGF-positive cells in telmisartan-treated group compared with vehicle-treated controls. From the three-dimensional reconstruction of the bony callus, telmisartan-treated group significantly increased the values of BV/TV by 21.7% and CsAr by 26.0% compared to the vehicle-treated controls at 5 weeks post-fracture. In summary, we demonstrate in the current study that telmisartan could promote fracture healing in a mice model via increasing mechanical strength and improving microstructure. The most mechanism is probably by an increase of cell proliferation and neovascularization associated with a decreased VEGF expression in hypertrophic chondrocytes.
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Comparative study of root growth and sucrose-cleaving enzymes in metallicolous and non-metallicolous populations of Rumex dentatus under copper stress.
Ecotoxicol. Environ. Saf.
PUBLISHED: 12-25-2013
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Sucrose metabolism in roots of metallophytes is very important for root growth and maintenance of heavy metal tolerance. However, rare researches have been carried out on this topic so far. We tested here a hypothesis that roots of copper-tolerant plants should manifest higher activities of sucrose-cleaving enzymes than non-tolerant plants for maintaining root growth under Cu stress. Plants of two contrasting populations of metallophyte Rumex dentatus, one from an ancient Cu mine (MP) and the other from a non-mine site (NMP), were treated with Cu in controlled experiments. Cu treatment resulted in a higher root biomass and root/shoot biomass ratio in MP compared to NMP. More complicated root system architecture was showed in MP under Cu stress. Activities and transcript levels of acid invertase as well as contents of sucrose and reducing sugar in MP were elevated under Cu treatment, while activities of neutral/alkaline invertase and sucrose synthase showed no significant differences between two populations. The results indicate important roles of acid invertase in governing root growth under Cu stress.
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A Tesla-type repetitive nanosecond pulse generator for solid dielectric breakdown research.
Rev Sci Instrum
PUBLISHED: 11-05-2013
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A Tesla-type repetitive nanosecond pulse generator including a pair of electrode and a matched absorption resistor is established for the application of solid dielectric breakdown research. As major components, a built-in Tesla transformer and a gas-gap switch are designed to boost and shape the output pulse, respectively; the electrode is to form the anticipated electric field; the resistor is parallel to the electrode to absorb the reflected energy from the test sample. The parameters of the generator are a pulse width of 10 ns, a rise and fall time of 3 ns, and a maximum amplitude of 300 kV. By modifying the primary circuit of the Tesla transformer, the generator can produce both positive and negative pulses at a repetition rate of 1-50 Hz. In addition, a real-time measurement and control system is established based on the solid dielectric breakdown requirements for this generator. With this system, experiments on test samples made of common insulation materials in pulsed power systems are conducted. The preliminary experimental results show that the constructed generator is capable to research the solid dielectric breakdown phenomenon on a nanosecond time scale.
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Generating diffuse discharge via repetitive nanosecond pulses and line-line electrodes in atmospheric air.
Rev Sci Instrum
PUBLISHED: 11-05-2013
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Diffuse discharge in atmospheric air can generate extremely high power density and large-scale non-thermal plasma. An achievable method of generating diffuse discharge is reported in this paper. Based on the resonance theory, a compact high-voltage repetitive nanosecond pulse generator (HRNPG) has been developed as discharge excitation source. The HRNPG mainly consists of repetitive charging circuit, Tesla transformer and sharpening switch. With the voltage lower than 1.0 kV, the primary repetitive charging circuit comprises two fast thyristors as low-voltage switches. A spiral Tesla transformer is designed to provide a peak transformation ratio of more than 100. The HRNPG prototype is capable of generating a pulse with over 100 kV peak voltage and ~30 ns rise-time at the repetition frequency of 500 Hz. Using the copper line electrodes with a diameter of 0.4 mm, the gaps with highly non-uniform electric field are structured. With the suitable gap spacing and applied pulse, the glow-like diffuse discharge has been generated in line-type and ring-type electrode pairs. Some typical images are presented.
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Nurses knowledge and attitudes on comfort nursing care for hospitalized patients.
Int J Nurs Pract
PUBLISHED: 10-15-2013
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To investigate the knowledge and attitudes of practicing nurses on comfort care for hospitalized patients, a survey was conducted in 311 registered nurses from a major teaching hospital. A total of 212 (68.1%) of the participants showed an adequate knowledge of comfort care. Participants who had 6 years or more working experience returned a higher mean scores on physiological and psychological aspects of comfort care (P?
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Genetically-engineered mesenchymal stem cells transfected with human HCN1 gene to create cardiac pacemaker cells.
J. Int. Med. Res.
PUBLISHED: 10-08-2013
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To test the proof-of-principle that genetically-engineered mesenchymal stem cells (MSCs) transfected with the human hyperpolarization-activated cyclic nucleotide-gated channel 1 (hHCN1) gene can be modified to become cardiac pacemaker cells.
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MicroRNA-21 in the pathogenesis of acute kidney injury.
Protein Cell
PUBLISHED: 09-13-2013
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Acute kidney injury (AKI), associated with significant morbidity and mortality, is widely known to involve epithelial apoptosis, excessive inflammation, and fibrosis in response to ischemia or reperfusion injury, which results in either chronic pathological changes or death. Therefore, it is imperative that investigations are conducted in order to find effective, early diagnoses, and therapeutic targets needed to help prevent and treat AKI. However, the mechanisms modulating the pathogenesis of AKI still remain largely undetermined. MicroRNAs (miRNAs), small non-coding RNA molecules, play an important role in several fundamental biological and pathological processes by a post transcriptional regulatory function of gene expression. MicroRNA-21 (miR-21) is a recently identified, typical miRNA that is functional as a regulator known to be involved in apoptosis as well as inflammatory and fibrotic signaling pathways in AKI. As a result, miR-21 is now considered a novel biomarker when diagnosing and treating AKI. This article reviews the correlative literature and research progress regarding the roles of miR-21 in AKI.
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[Expression of blood Th17 and CD4(+) CD25(+) Treg cells in patients with aplastic anemia].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 09-04-2013
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This study was aimed to investigate the expression of blood Th17 and CD4(+) CD25(+) regulatory T cells (Treg) in the patients with aplastic anemia(AA). Forty-five patients with AA were enrolled into this study, and were divided into mild aplastic anemia(MAA) group (n = 25) and severe aplastic anemia group(SAA) (n = 20), blood cell count was recorded. 15 healthy donors were enrolled as control. Proportions of blood Th17 and CD4(+) CD25(+) Treg cells were determined by flow cytometry. The serum levels of IL-17, IFN-? and TNF-?, as well as their concentrations in culture supernatant of phytohemagglutinin(PHA) -stimulated peripheral blood mononuclear cells, were measured by ELISA. The results showed that the proportions of blood Th17 cells and concentration of blood serum IL-17 and IFN-? increased in patients with SAA, compared with MAA and normal controls, but CD4(+) CD25(+) Foxp3(+) Treg cells obviously decreased in patients with SAA. The concentrations of IL-17 and IFN-? significantly increased in culture supernatant of SAA group. Hemoglobin level in the patients with AA negatively correlated with the population of Th17 cells and serum IL-17 level, whereas positively correlated with the expression of CD4(+) CD25(+)Treg cells. It is concluded that the increased response of Th17 cells and deficiency of CD4(+) CD25(+) Treg cells present in severe aplastic anemia. The severity of anemia may be related with the imbalance between Th17 and CD4(+) CD25(+)Treg cell response.
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Effect of angiotensin II type I receptor blocker losartan on bone deterioration in orchiectomized male hypertensive and normotensive rats.
Chin. Med. J.
PUBLISHED: 07-24-2013
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Epidemiological study showed that the use of angiotensin-converting enzyme inhibitors was associated with higher bone mineral density (BMD) in older people, especially male subjects, which suggested that angiotensin II may have a detrimental effect on bone. Therefore, blocking its effect may have a beneficial effect on bone health.
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ZincExplorer: an accurate hybrid method to improve the prediction of zinc-binding sites from protein sequences.
Mol Biosyst
PUBLISHED: 07-18-2013
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As one of the most important trace elements within an organism, zinc has been shown to be involved in numerous biological processes and closely implicated in various diseases. The zinc ion is important for proteins to perform their functional roles. To provide in-depth functional annotation of zinc-binding proteins, an initial but crucial step is the accurate recognition of zinc-binding sites. Motivated by the biological importance of zinc, we propose a new method called ZincExplorer to predict zinc-binding sites from protein sequences. ZincExplorer is a hybrid method that can accurately predict zinc-binding sites from protein sequences. It integrates the outputs of three different types of predictors, namely, SVM-, cluster- and template-based predictors. Four types of zinc-binding amino acids CHEDs (i.e. CYS, HIS, ASP and GLU) could be predicted using ZincExplorer. It achieved a high AURPC (Area Under Recall-Precision Curve) of 0.851, and a precision of 85.6% (specificity = 98.4%, MCC = 0.747) at the 70.0% recall for the CHEDs on the 5-fold cross-validation test. When tested on an independent dataset containing 2023 zinc-binding CHEDs and 14,493 non-zinc-binding CHEDs, it achieved about 3-8% higher AURPC in comparison to two other sequence-based predictors. Moreover, ZincExplorer could also identify the interdependent relationships (IRs) of the predicted zinc-binding sites bound to the same zinc ion, which makes it a useful tool for providing in-depth zinc-binding site annotation.
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[Chemical constituents of surface layer of Poria cocos and their pharmacological properties (I)].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 07-16-2013
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The surface layer of the sclerotia of Poria cocos, named Fu-Ling-Pi, is used as a diuretic in traditional Chinese medicine to treat edema and urinary dysfunction. Recent studies have showed that the triterpenes (lanostane and 3,4-secolanostane skeletons) and polysaccharides (beta-pachyman) are the main components of Fu-Ling-Pi and they exhibited various biological activities, such as anti-tumor, antibacterial and antioxidant, etc. This review was focused on the chemistry, pharmacology, and clinical uses of this drug and it may provide scientific foundation for further development and utilization of Fulingpi.
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The effects of pipeline construction disturbance on soil properties and restoration cycle.
Environ Monit Assess
PUBLISHED: 07-05-2013
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Disturbance to the physical-chemical properties of soil caused by pipeline installation was evaluated using two soil quality indices to identify the scale of disturbance and the restoration cycle. The integrated soil quality index (SQI) was used to evaluate soil property changes in different pipeline zones (0, 10, 20, and 50 m from the pipeline) at sites 1 and 2. The soil restoration index (SRI) was used to estimate soil recovery from three pipelines with different recovery periods (2, 6, and 8 years) at site 3. The results showed that the adverse effects of pipeline construction on soil properties mainly occurred in the right-of-way (ROW) areas and the impaired zones were in the order trench?>?piling and working areas?>?20 and 50 m. The soil restoration cycle may be complete within 6 years of construction. At site 3, the SRI in the ROW area of a pipeline after 6 years of restoration was close to 100 %, showing full soil recovery. However, the SRI in the disturbed areas of a pipeline after 2 years of restoration was much lower than that after 6 years of restoration, indicating that the soil was still recovering from the disturbance. The topography may change the intensity of disturbance in different areas due to the movement patterns of heavy machinery and traffic routes. There were local variations in the SQI within the pipeline zones, with flat areas suffering greater disturbance than hilly areas, indicating that topography should be considered in a pipelines environmental impact assessment.
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Internal structure-mediated ultrafast energy transfer in self-assembled polymer-blend dots.
Nanoscale
PUBLISHED: 07-03-2013
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Applications of polymeric semiconductors in organic electronics and biosensors depend critically on the nature of energy transfer in these materials. Important questions arise as to how this long-range transport degrades in amorphous condensed solids which are most amenable to low-cost optoelectronic devices and how fast energy transfer could occur. Here, we address these in disordered, densely packed nanoparticles made from green-light-harvesting host polymers (PFBT) and deep-red-emitting dopant polymers (PF-DBT5). By femtosecond selective excitation of donor (BT) units, we study in detail the internal structure-mediated energy transfer to uniformly distributed, seldom acceptor (DBT) units. It has been unambiguously demonstrated that the creation of interchain species is responsible for the limitation of bulk exciton diffusion length in polymer materials. This interchain Förster resonance energy transfer (FRET) becomes a preferred and dominant channel, and near 100% energy transfer efficiency could be achieved at high acceptor concentrations (>10 wt%). Side-chain carboxylic acid groups in functionalized polymer-blend dots slightly slow down the FRET rate, but it could not affect the Förster radius and FRET efficiency. These findings imply that a greater understanding of the role of interchain species could be an efficient approach to improve the cell efficiency.
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Diuretic activity of some fractions of the epidermis of Poria cocos.
J Ethnopharmacol
PUBLISHED: 06-24-2013
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Poria cocos Wolf (Polyporaceae) is a well-known medicinal fungus, the epidermis ("Fu-Ling-Pi" in Chinese) of the sclerotia is used as a diuretic for treating oedema and promoting the diuretic process. In this paper we report on the diuretic activity in rats of petroleum ether, ethyl acetate, n-butanol and the remaining fractions of the ethanol extract from the epidermis of Poria cocos.
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[Ecological effect of hygroscopic and condensate water on biological soil crusts in Shapotou region of China].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 06-13-2013
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By the method of field experiment combined with laboratory analysis, this paper studied the ecological significance of hygroscopic and condensate water on the biological soil crusts in the vegetation sand-fixing area in Shapotou region of China. In the study area, 90% of hygroscopic and condensate water was within the 3 cm soil depth, which didn t affect the surface soil water content. The hygroscopic and condensate water generated at night involved in the exchange process of soil surface water and atmosphere water vapor, made up the loss of soil water due to the evaporation during the day, and made the surface soil water not reduced rapidly. The amount of the generated hygroscopic and condensate water had a positive correlation with the chlorophyll content of biological soil crusts, indicating that the hygroscopic and condensate water could improve the growth activity of the biological soil crusts, and thus, benefit the biomass accumulation of the crusts.
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Anti-inflammatory role of cannabidiol and O-1602 in cerulein-induced acute pancreatitis in mice.
Pancreas
PUBLISHED: 05-31-2013
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The anti-inflammatory effects of O-1602 and cannabidiol (CBD), the ligands of G protein-coupled receptor 55 (GPR55), on experimental acute pancreatitis (AP) were investigated.
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Hydrodynamically enforced entropic Brownian pump.
J Chem Phys
PUBLISHED: 04-26-2013
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Transport of overdamped Brownian particles in a finite hydrodynamical channel is investigated in the presence of the ac driving force and the pressure-driven flow. The system is bounded by two particle reservoirs. With the help of the Fick-Jacobs method, we obtain the directed current of Brownian particles and the pumping capacity of the system. The directed transport is determined by the competitions among the asymmetry of the channel, the ac driving force, the pressure-driven flow, and the concentration difference. Their interplays can exhibit the peculiar properties. Remarkably, the particles can be pumped through the channel from the lower concentration reservoir to the higher concentration one, or from the lower pressure side to the higher pressure one. In addition, due to the existence of the pressure drop, ac driving force still plays the significant role on directed transport even in a completely symmetric channel. Our results could be implemented in constrained structures with narrow channels or pores where the particles are suspended in a solvent.
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Effects of electromagnetic pulse on polydactyly of mouse fetuses.
Theriogenology
PUBLISHED: 03-18-2013
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There is an increasing public concern regarding potential health impacts from electromagnetic radiation exposure. Embryonic development is sensitive to the external environment, and limb development is vital for life quality. To determine the effects of electromagnetic pulse (EMP) on polydactyly of mouse fetuses, pregnant mice were sham-exposed or exposed to EMP (400 kV/m with 400 pulses) from Days 7 to 10 of pregnancy (Day 0 = day of detection of vaginal plug). As a positive control, mice were treated with 5-bromodeoxyuridine on Days 9 and 10. On Days 11 or 18, the fetuses were isolated. Compared with the sham-exposed group, the group exposed to EMP had increased rates of polydactyly fetuses (5.1% vs. 0.6%, P < 0.05) and abnormal gene expression (22.2% vs. 2.8%, P < 0.05). Ectopic expression of Fgf4 was detected in the apical ectodermal ridge, whereas overexpression and ectopic expression of Shh were detected in the zone of polarizing activity of limbs in the EMP-exposed group and in the positive control group. However, expression of Gli3 decreased in mesenchyme cells in those two groups. The percentages of programmed cell death of limbs in EMP-exposed and positive control group were decreased (3.57% and 2.94%, respectively, P < 0.05, compared with 7.76% in sham-exposed group). In conclusion, polydactyly induced by EMP was accompanied by abnormal expression of the above-mentioned genes and decreased percentage of programmed cell death during limb development.
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Urinary metabonomic study of the surface layer of Poria cocos as an effective treatment for chronic renal injury in rats.
J Ethnopharmacol
PUBLISHED: 03-18-2013
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Poria cocos Wolf (Polyporaceae) is a well-known medicinal fungus. The epidermis of the sclerotia ("Fu-Ling-Pi" in Chinese) is used as a diuretic and traditionally used for promoting urination and reduce edema.
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Renal metabolic profiling of early renal injury and renoprotective effects of Poria cocos epidermis using UPLC Q-TOF/HSMS/MSE.
J Pharm Biomed Anal
PUBLISHED: 03-16-2013
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Poria cocos epidermis is one of ancient traditional Chinese medicines (TCMs), which is usually used for the treatment of chronic kidney disease (CKD) for thousands of years in China. A metabonomic approach based on ultra performance liquid chromatography coupled with quadrupole time-of-flight high-sensitivity mass spectrometry (UPLC Q-TOF/HSMS) and a mass spectrometry(Elevated Energy) (MS(E)) data collection technique was developed to obtained a systematic view of the development and progression of CKD and biochemistry mechanism of therapeutic effects of P. cocos epidermis (Fu-Ling-Pi, FLP). By partial least squares-discriminate analysis, 19 metabolites were identified as potential biomarkers of CKD. Among the 19 biomarkers, 10 biomarkers including eicosapentaenoic acid, docosahexaenoic acid, lysoPC(20:4), lysoPC(18:2), lysoPC(15:0), lysoPE(20:0/0:0), indoxyl sulfate, hippuric acid, p-cresol sulfate and allantoin were reversed to the control level in FLP-treated groups. The study indicates that FLP treatment can ameliorate CKD by intervening in some dominating metabolic pathways, such as fatty acid metabolism, phospholipid metabolism, purine metabolism and tryptophan metabolism. This work was for the first time to investigate the FLP therapeutic effect based on metabonomics technology, which is a potentially powerful tool to study the TCMs.
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Tunable Dirac fermion dynamics in topological insulators.
Sci Rep
PUBLISHED: 03-14-2013
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Three-dimensional topological insulators are characterized by insulating bulk state and metallic surface state involving relativistic Dirac fermions which are responsible for exotic quantum phenomena and potential applications in spintronics and quantum computations. It is essential to understand how the Dirac fermions interact with other electrons, phonons and disorders. Here we report super-high resolution angle-resolved photoemission studies on the Dirac fermion dynamics in the prototypical Bi2(Te,Se)3 topological insulators. We have directly revealed signatures of the electron-phonon coupling and found that the electron-disorder interaction dominates the scattering process. The Dirac fermion dynamics in Bi2(Te3-xSex) topological insulators can be tuned by varying the composition, x, or by controlling the charge carriers. Our findings provide crucial information in understanding and engineering the electron dynamics of the Dirac fermions for fundamental studies and potential applications.
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Inhibition of Wnt signaling induces cell apoptosis and suppresses cell proliferation in cholangiocarcinoma cells.
Oncol. Rep.
PUBLISHED: 03-10-2013
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The aim of the present study was to explore possible gene therapy for hilar cholangiocarcinoma by detecting the activation of the Wnt signaling pathway in 4 cholangiocarcinoma cell lines and inhibiting its expression by RNA interference (RNAi) targeting key factors of this pathway. The expression levels of the Wnt pathway-related factors, Wnt2, Wnt3, ?-catenin and transcription factor 4, and its target genes, c-myc and cyclin D1, in 4 cholangiocarcinoma cell lines were detected by RT-PCR, western blotting and immunofluorescence microscopy. After transfection of siRNAs targeting Wnt2 and ?-catenin into FRH0201 cells, the expression of the Wnt pathway-related factors and its target genes was again detected, and the cell cycle distribution, apoptosis and proliferation were analyzed by flow cytometry and MTT assay. Activation of the Wnt pathway and the expression of its target genes were detected in all 4 cell lines at various levels. After siRNA transfection, the expression of the target genes in the FRH0201 cells was significantly downregulated. In addition, the Wnt pathway was blocked, cell apoptosis was enhanced and cell proliferation was suppressed. In conclusion, the Wnt signaling pathway is activated in cholangiocarcinoma cells. RNAi technology targeting Wnt2 and ?-catenin may be a possible gene therapy for hilar cholangiocarcinoma.
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BODIPY-based fluorometric sensor array for the highly sensitive identification of heavy-metal ions.
Anal. Chim. Acta
PUBLISHED: 02-26-2013
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A BODIPY(4,4-difluoro-4-bora-3a,4a-diaza-s-indacene)-based fluorometric sensor array has been developed for the highly sensitive detection of eight heavy-metal ions at micromolar concentration. The di-2-picolyamine (DPA) derivatives combine high affinities for a variety of heavy-metal ions with the capacity to perturb the fluorescence properties of BODIPY, making them perfectly suitable for the design of fluorometric sensor arrays for heavy-metal ions. 12 cross-reactive BODIPY fluorescent indicators provide facile identification of the heavy-metal ions using a standard chemometric approach (hierarchical clustering analysis); no misclassifications were found over 45 trials. Clear differentiation among heavy-metal ions as a function of concentration was also achieved, even down to 10(-7)M. A semi-quantitative interpolation of the heavy-metal concentration is obtained by comparing the total Euclidean distance of the measurement with a set of known concentrations in the library.
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[Coal tar pitch smoke extract-induced pyroptosis in human bronchial epithelial cells].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 02-26-2013
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To explore whether coal tar pitch smoke extract (CTP) induced pyroptosis in human bronchial epithelial cells (BEAS-2B).
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Electromagnetic pulse exposure induces overexpression of beta amyloid protein in rats.
Arch. Med. Res.
PUBLISHED: 02-20-2013
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With the developing and widely used electromagnetic field (EMF) technology, more and more studies are focusing on the relationship between EMF and Alzheimers disease (AD). Electromagnetic pulse (EMP) is one type of widely used EMF. This study aimed to clarify whether EMP exposure could induce cognitive and memory impairment, thus finding a possible relationship between EMP and AD.
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Ultra performance liquid chromatography-based metabonomic study of therapeutic effect of the surface layer of Poria cocos on adenine-induced chronic kidney disease provides new insight into anti-fibrosis mechanism.
PLoS ONE
PUBLISHED: 02-15-2013
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The surface layer of Poria cocos (Fu-Ling-Pi, FLP) is commonly used in traditional Chinese medicine and its diuretic effect was confirmed in rat. Ultra performance liquid chromatography/quadrupole time-of-flight high-sensitivity mass spectrometry and a novel mass spectrometry(Elevated Energy) data collection technique was employed to investigate metabonomic characteristics of chronic kidney disease (CKD) induced from adenine excess and the protective effects of FLP. Multiple metabolites are detected in the CKD and are correlated with progressive renal injury. Among these biomarkers, lysoPC(18?0), tetracosahexaenoic acid, lysoPC(18?2), creatinine, lysoPC (16?0) and lysoPE(22?0/0?0) in the FLP-treated group were completely reversed to levels in the control group which lacked CKD. Combined with biochemistry and histopathology results, the changes in serum metabolites indicate that the perturbations of phospholipids metabolism, energy metabolism and amino acid metabolism are related to adenine-induced CKD and to the interventions of FLP on all the three metabolic pathways. FLP may regulate the metabolism of these biomarkers, especially their efficient utilization within the context of CKD. Furthermore, these biomarkers might serve as characteristics to explain the mechanisms of FLP.
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Gender difference of serum angiotensin-converting enzyme (ACE) activity in DD genotype of ACE insertion/deletion polymorphism in elderly Chinese.
J Renin Angiotensin Aldosterone Syst
PUBLISHED: 02-08-2013
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INTRODUCTION: In this study we investigated the gender difference of serum angiotensin-converting enzyme (ACE) activity in a population of Hong Kong-dwelling elderly Chinese. MATERIALS AND METHODS: A total of 1767 (843 male, 924 female) Hong Kong-dwelling elderly Chinese were recruited. ACE I/D genotypes were identified by polymerase chain reaction amplification and serum ACE activity was determined using a commercially available kinetic kit. ACE I/D genotype distribution was compared by chi-square test, the correlation between ACE I/D polymorphism and serum ACE activity was analysed by ANOVA test and gender difference of serum ACE activity of different genotypes was compared by independent sample t-test. RESULTS: No statistically significant difference of genotype distribution between male and female subjects was found. Serum ACE activity was significantly correlated with ACE genotype. Overall, there was no gender difference of serum ACE activity; however, when sub-grouping the subjects by ACE I/D genotype, male subjects with DD genotype had higher serum ACE activity than female subjects with DD genotype. CONCLUSIONS: No significant gender difference of genotype distribution was found in elderly Chinese. Serum ACE activity was significantly correlated with ACE I/D polymorphism in elderly Chinese. Male subjects with DD genotype had higher serum ACE activity than female subjects with DD genotype.
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Pharmacokinetics of 2,3,5,4-tetrahydroxystilbene-2-O-?-D-glucoside in rat using ultra-performance LC-quadrupole TOF-MS.
J Sep Sci
PUBLISHED: 02-01-2013
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2,3,5,4-Tetrahydroxystilbene-2-O-?-D-glucoside (THSG) from Polygoni multiflori has been demonstrated to possess a variety of pharmacological activities, including antioxidant, anti-inflammatory and hepatoprotective activities. Ultra-performance LC-quadrupole TOF-MS with MS Elevated Energy data collection technique and rapid resolution LC with diode array detection and ESI multistage MS(n) methods were developed for the pharmacokinetics, tissue distribution, metabolism, and excretion studies of THSG in rats following a single intravenous or oral dose. The three metabolites were identified by rapid resolution LC-MS(n). The concentrations of the THSG in rat plasma, bile, urine, feces, or tissue samples were determined by ultra-performance LC-MS. The results showed that THSG was rapidly distributed and eliminated from rat plasma. After the intravenous administration, THSG was mainly distributing in the liver, heart, and lung. For the rat, the major distribution tissues after oral administration were heart, kidney, liver, and lung. There was no long-term storage of THSG in rat tissues. Total recoveries of THSG within 24 h were low (0.1% in bile, 0.007% in urine, and 0.063% in feces) and THSG was excreted mainly in the forms of metabolites, which may resulted from biotransformation in the liver.
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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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