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Find video protocols related to scientific articles indexed in Pubmed.
Impaired Neural Differentiation Potency by Retinoic Acid Receptor-? Pathway Defect in Induced Pluripotent Stem Cells.
Cell Reprogram
PUBLISHED: 11-04-2014
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Abstract Induced pluripotent stem cells (iPSCs) are reprogrammed from somatic cells via ectopic gene expression and, similarly to embryonic stem cells (ESCs), possess powerful abilities to self-renew and differentiate into cells of various lineages. However, the neural differentiation potency of iPSCs remains unknown. In this study, we demonstrated the neural differentiation ability of iPSCs compared with ESCs using an retinoic acid (RA) induction system. The neural differentiation efficiency of iPSCs was obviously lower than that of ESCs. Retinoic acid receptor-? (RAR?) was critical in the RA-induced neural differentiation of iPSCs, and the effect of RAR? was confirmed by applying a specific RAR? antagonist ER50891 to ESCs. These findings indicate that iPSCs do not possess the complete properties that ESCs have.
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Suppression of the SOX2 neural effector gene by PRDM1 promotes human germ cell fate in embryonic stem cells.
Stem Cell Reports
PUBLISHED: 02-11-2014
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The mechanisms of transcriptional regulation underlying human primordial germ cell (PGC) differentiation are largely unknown. The transcriptional repressor Prdm1/Blimp-1 is known to play a critical role in controlling germ cell specification in mice. Here, we show that PRDM1 is expressed in developing human gonads and contributes to the determination of germline versus neural fate in early development. We show that knockdown of PRDM1 in human embryonic stem cells (hESCs) impairs germline potential and upregulates neural genes. Conversely, ectopic expression of PRDM1 in hESCs promotes the generation of cells that exhibit phenotypic and transcriptomic features of early PGCs. Furthermore, PRDM1 suppresses transcription of SOX2. Overexpression of SOX2 in hESCs under conditions favoring germline differentiation skews cell fate from the germline to the neural lineage. Collectively, our results demonstrate that PRDM1 serves as a molecular switch to modulate the divergence of neural or germline fates through repression of SOX2 during human development.
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Both PAR1 and PAR2 Promote Seedling Photomorphogenesis in Multiple Light Signaling Pathways.
Plant Physiol.
PUBLISHED: 12-12-2013
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Arabidopsis seedlings undergo photomorphogenesis in the light and etiolation in the dark. Light-activated photoreceptors transduce the light signals through a series of photomorphogenesis promoting or repressing factors to modulate many developmental processes in plants, such as photomorphogenesis and shade avoidance. CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) is a conserved RING finger E3 ubiquitin ligase, which mediates degradation of several photomorphogenesis promoting factors, including ELONGATED HYPOCOTYL5 (HY5) and LONG HYPOCOTYL IN FAR-RED1 (HFR1), through a 26S proteasome-dependent pathway. PHYTOCHROME RAPIDLY REGULATED 1 (PAR1) was first detected as an early repressed gene in both phytochrome (phy) A-mediated far-red (FR) and phyB-mediated red (R) signaling pathways, and subsequent studies showed that both PAR1 and PAR2 are negative factors of shade avoidance in Arabidopsis. However, the role of PAR1 and PAR2 in seedling de-etiolation and their relationships with other photomorphogenesis promoting and repressing factors are largely unknown. Here, we confirmed that both PAR1 and PAR2 redundantly enhance seedling de-etiolation in multiple photoreceptor signaling pathways. Their transcript abundances are repressed by phyA, phyB, and cryptochrome 1 (CRY1) under FR, R, and blue (B) light conditions, respectively. Both PAR1 and PAR2 act downstream of COP1, and COP1 mediates the degradation of PAR1 and PAR2 through the 26S proteasome pathway. Both PAR1 and PAR2 act in a separate pathway from HY5 and HFR1 under different light conditions, except for sharing in the same pathway with HFR1 under FR light. Together, our results substantiate that PAR1 and PAR2 are positive factors functioning in multiple photoreceptor signaling pathways during seedling de-etiolation.
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Lhx2 regulates a cortex-specific mechanism for barrel formation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-21-2013
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LIM homeodomain transcription factors are critical regulators of early development in multiple systems but have yet to be examined for a role in circuit formation. The LIM homeobox gene Lhx2 is expressed in cortical progenitors during development and also in the superficial layers of the neocortex in maturity. However, analysis of Lhx2 function at later stages of cortical development has been hampered by severe phenotypes associated with early loss of function. We identified a particular Cre-recombinase line that acts in the cortical primordium after its specification is complete, permitting an analysis of Lhx2 function in neocortical lamination, regionalization, and circuit formation by selective elimination of Lhx2 in the dorsal telencephalon. We report a profound disruption of cortical neuroanatomical and molecular features upon loss of Lhx2 in the cortex from embryonic day 11.5. A unique feature of cortical circuitry, the somatosensory barrels, is undetectable, and molecular patterning of cortical regions appears disrupted. Surprisingly, thalamocortical afferents innervate the mutant cortex with apparently normal regional specificity. Electrophysiological recordings reveal a loss of responses evoked by stimulation of individual whiskers, but responses to simultaneous stimulation of multiple whiskers were present, suggesting that thalamic afferents are unable to organize the neurocircuitry for barrel formation because of a cortex-specific requirement of Lhx2. We report that Lhx2 is required for the expression of transcription factor paired box gene 6, axon guidance molecule Ephrin A5, and the receptor NMDA receptor 1. These genes may mediate Lhx2 function in the formation of specialized neurocircuitry necessary for neocortical function.
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Whole transcriptome sequencing reveals genes involved in plastid/chloroplast division and development are regulated by the HP1/DDB1 at an early stage of tomato fruit development.
Planta
PUBLISHED: 07-24-2013
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The phenotype of tomato high pigment-1 (hp1) mutant is characterized by overproduction of pigments including chlorophyll and carotenoids during fruit development and ripening. Although the increased plastid compartment size has been thought to largely attribute to the enhanced pigmentation, the molecular aspects of how the HP1/DDB1 gene manipulates plastid biogenesis and development are largely unknown. In the present study, we compared transcriptome profiles of immature fruit pericarp tissue between tomato cv. Ailsa Craig (WT) and its isogenic hp1 mutant. Over 20 million sequence reads, representing > 1.6 Gb sequence data per sample, were generated and assembled into 21,972 and 22,167 gene models in WT and hp1, respectively, accounting for over 60 % official gene models in both samples. Subsequent analyses revealed that 8,322 and 7,989 alternative splicing events, 8833 or 8510 extended 5-UTRs, 8,263 or 8,939 extended 3-UTRs, and 1,136 and 1,133 novel transcripts, exist in WT and hp1, respectively. Significant differences in expression level of 880 genes were detected between the WT and hp1, many of which are involved in signaling transduction, transcription regulation and biotic and abiotic stresses response. Distinctly, RNA-seq datasets, quantitative RT-PCR analyses demonstrate that, in hp1 mutant pericarp tissue at early developmental stage, an apparent expression alteration was found in several regulators directly involved in plastid division and development. These results provide a useful reference for a more accurate and more detailed characterization of the molecular process in the development and pigmentation of tomato fruits.
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LHX2 regulates the neural differentiation of human embryonic stem cells via transcriptional modulation of PAX6 and CER1.
Nucleic Acids Res.
PUBLISHED: 06-26-2013
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The LIM homeobox 2 transcription factor Lhx2 is known to control crucial aspects of neural development in various species. However, its function in human neural development is still elusive. Here, we demonstrate that LHX2 plays a critical role in human neural differentiation, using human embryonic stem cells (hESCs) as a model. In hESC-derived neural progenitors (hESC-NPs), LHX2 was found to be expressed before PAX6, and co-expressed with early neural markers. Conditional ectopic expression of LHX2 promoted neural differentiation, whereas disruption of LHX2 expression in hESCs significantly impaired neural differentiation. Furthermore, we have demonstrated that LHX2 regulates neural differentiation at two levels: first, it promotes expression of PAX6 by binding to its active enhancers, and second, it attenuates BMP and WNT signaling by promoting expression of the BMP and WNT antagonist Cerberus 1 gene (CER1), to inhibit non-neural differentiation. These findings indicate that LHX2 regulates the transcription of downstream intrinsic and extrinsic molecules that are essential for early neural differentiation in human.
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[Analysis of first flush effect of typical underlying surface runoff in Beijing urban city].
Huan Jing Ke Xue
PUBLISHED: 03-16-2013
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Rapid increase of the urban impervious underlying surfaces causes a great increase of urban runoff and the accumulation of pollutants on the roof and road surfaces brings many pollutants into the drainage system with the runoff, and it thus becomes a great threat to the urban water environment. To know the runoff pollution process and to build scientific basis for pollutant control, runoff processes from the roof and road surfaces were monitored and analyzed from 2004 to 2006, and the runoff EMC (Event Mean Concentration) was calculated. It was found that two types of runoff were seriously polluted by COD and TN. The COD and TN of roof runoff exceeded the fifth level of the surface water environmental quality standard (GB 3838-2002) by 3.64 and 4.80 times, respectively, and the COD and TN of road runoff exceeded by 3.73 and 1.07 times, respectively. M (V) curve was used to determine the relation between runoff volume and runoff pollution load. Various degrees of the first flush phenomenon were found for TSS, COD, TN and TP in roof runoff. But this phenomenon occurred only for TSS and TP of the road runoff, and on the whole it was not obvious. Properties of the underlying surfaces, rainfall intensity, and pollutant accumulation are all important factors affecting the roof and road runoff pollutant emission characteristics.
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[The effect of moxifloxacin on apoptosis of airway smooth muscle cells and mitochondria membrane potential].
Zhonghua Jie He He Hu Xi Za Zhi
PUBLISHED: 12-20-2011
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To observe the effects of moxifloxacin at various concentrations on the expression of Caspase-3, the alteration of mitochondria membrane potential (??m) and the apoptosis of airway smooth muscle cells (ASMCs), and to explore the possible mechanisms.
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[Preliminary studies on pathogenic microorganisms laboratory-acquired infections cases in recent years and its control strategies].
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi
PUBLISHED: 11-25-2011
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To analyze and study types, infections routes and causes of global pathogenic microorganisms laboratory-acquired infections cases reported in the literatures from 2000 to 2009 and to discuss prevention and control strategies.
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[Antibiotic resistance and molecular typing of Listeria monocytogenes from foods in Shandong province from 2009 to 2010].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 09-03-2011
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To know the antibiotic resistance and molecular characteristics of Listeria monocytogenes in Shandong province and to study the relationship between antibiotic resistance phenotypes and genome types.
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Refinement of the theory for extracting cell dielectric properties from dielectrophoresis and electrorotation experiments.
Biomicrofluidics
PUBLISHED: 08-11-2011
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A modified theory is proposed for extracting cell dielectric properties from the peak frequency measurement of electrorotation (ER) and the crossover frequency measurement of dielectrophoresis (DEP). Current theory in the literature is based on the low frequency (DC) approximations for the equivalent cell permittivity and conductivity, which are valid when the measurements are performed in a medium with conductivity less than 1 mS/m. The present theory extracts the cell properties through optimizing an expression for the medium conductivity in terms of the peak ER, or DEP crossover, frequency according to its definition using full expressions of equivalent cell permittivity and conductivity. Various levels of approximation of the theory are proposed and discussed through a scaling analysis. The present theory can extract both membrane and interior properties from the low and the high peak ER, or DEP crossover, frequencies for any medium conductivity provided the peak ER, or DEP crossover, frequency exists. It can be reduced to the linear theory for the low peak ER and DEP crossover frequencies in the literature when the medium conductivity is less than 10 mS/m. However, we can determine the membrane capacitance and conductance via the slope and intercept, respectively, of the straight line fitting of the ER peak and DEP frequency against medium conductivity data according to the linear theory only when the intercept dominates the experimental uncertainty, which occurs when the medium conductivity is less than 1 mS/m in practice.
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Targeted methylation of two tumor suppressor genes is sufficient to transform mesenchymal stem cells into cancer stem/initiating cells.
Cancer Res.
PUBLISHED: 04-25-2011
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Although DNA hypermethylation within promoter CpG islands is highly correlated with tumorigenesis, it has not been established whether DNA hypermethylation within a specific tumor suppressor gene (TSG) is sufficient to fully transform a somatic stem cell. In this study, we addressed this question using a novel targeted DNA methylation technique to methylate the promoters of HIC1 and RassF1A, two well-established TSGs, along with a two-component reporter system to visualize successful targeting of human bone marrow-derived mesenchymal stem cells (MSC) as a model cell system. MSCs harboring targeted promoter methylations of HIC1/RassF1A displayed several features of cancer stem/initiating cells including loss of anchorage dependence, increased colony formation capability, drug resistance, and pluripotency. Notably, inoculation of immunodeficient mice with low numbers of targeted MSC resulted in tumor formation, and subsequent serial xenotransplantation and immunohistochemistry confirmed the presence of stem cell markers and MSC lineage in tumor xenografts. Consistent with the expected mechanism of TSG hypermethylation, treatment of the targeted MSC with a DNA methyltransferase inhibitor reversed their tumorigenic phenotype. To our knowledge, this is the first direct demonstration that aberrant TSG hypermethylation is sufficient to transform a somatic stem cell into a fully malignant cell with cancer stem/initiating properties.
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Different functions and expression profiles of curcin and curcin-L in Jatropha curcas L.
Z. Naturforsch., C, J. Biosci.
PUBLISHED: 07-27-2010
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To date, two types of ribosome-inactivating proteins (RIPs) have been found in Jatropha curcas. One is curcin, which has been isolated from the endosperm, and the other is curcin-L, which is expressed in leaves upon stress treatment. Phylogenetic analysis of the predicted amino acid sequences of the RIPs in plants revealed that these belong to a major subfamily and are close to trichosanthin (TCS). Studies on the mRNA and protein levels showed that both curcin and curcin-L have an organ-specific expression pattern. Curcin is only expressed and accumulated in the endosperm; its expression begins in the globular embryo period and peaks during the mature embryo period. In contrast, curcin-L is only expressed in the leaves, but its expression is induced by certain conditions such as treatment with phytohormones or polyethylene glycol, exposure to high and low temperatures, and fungal infection. Analysis of the 5 flanking regions of curcin and curcin-L revealed that the 5 flanking region of curcin-L has three major inserted fragments, which are not present in the corresponding region of curcin. Comparison of characteristic cis-elements suggests the presence of several motifs that are involved in the endosperm-specific expression in the 5 flanking region of curcin, while in curcin-L some stress- and defense-responsive motifs are found to be mainly located in the three inserted fragments. Comparison of the antifungal activity of the two RIPs showed that the one of curcin-L is higher than that of curcin. Differences in the expression and activity of curcin and curcin-L suggest that these two RIPs have different functions.
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Krüppel-like transcription factor 4 contributes to maintenance of telomerase activity in stem cells.
Stem Cells
PUBLISHED: 07-15-2010
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The zinc finger Krüppel-like transcription factor 4 (KLF4) has been implicated in cancer formation and stem cell regulation. However, the function of KLF4 in tumorigenesis and stem cell regulation are poorly understood due to limited knowledge of its targets in these cells. In this study, we have revealed a surprising link between KLF4 and regulation of telomerase that offers important insight into how KLF4 contributes to cancer formation and stem cell regulation. KLF4 sufficiently activated expression of the human telomerase catalytic subunit, human telomerase reverse transcriptase (hTERT), in telomerase-low alternative lengthening of telomeres (ALT), and fibroblast cells, while downregulation of KLF4 reduced its expression in cancerous and stem cells, which normally exhibits high expression. Furthermore, KLF4-dependent induction of hTERT was mediated by a KLF4 binding site in the proximal promoter region of hTERT. In human embryonic stem cells, expression of hTERT replaced KLF4 function to maintain their self-renewal. Therefore, our findings demonstrate that hTERT is one of the major targets of KLF4 in cancer and stem cells to maintain long-term proliferation potential.
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Fuzzy comprehensive evaluation for selecting mini watermelon cultivars.
J. Sci. Food Agric.
PUBLISHED: 04-01-2010
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The traditional method for selecting suitable mini watermelon cultivars has been shown to be flawed. The aim of the present study was to assess 11 mini watermelon cultivars using a new method, two-level fuzzy comprehensive evaluation (FCE). Three different characteristics for selecting the best cultivars were chosen to establish the evaluation index system, namely commercial trait, early maturity and high yield quality. Fifteen specific factors were used to reflect these three characteristics.
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A conserved unusual posttranscriptional processing mediated by short, direct repeated (SDR) sequences in plants.
J Genet Genomics
PUBLISHED: 02-23-2010
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In several stress responsive gene loci of monocot cereal crops, we have previously identified an unusual posttranscriptional processing mediated by paired presence of short direct repeated (SDR) sequences at 5 and 3 splicing junctions that are distinct from conventional (U2/U12-type) splicing boundaries. By using the known SDR-containing sequences as probes, 24 plant candidate genes involved in diverse functional pathways from both monocots and dicots that potentially possess SDR-mediated posttranscriptional processing were predicted in the GenBank database. The SDRs-mediated posttranscriptional processing events including cis- and trans-actions were experimentally detected in majority of the predicted candidates. Extensive sequence analysis demonstrates several types of SDR-associated splicing peculiarities including partial exon deletion, exon fragment repetition, exon fragment scrambling and trans-splicing that result in either loss of partial exon or unusual exonic sequence rearrangements within or between RNA molecules. In addition, we show that the paired presence of SDR is necessary but not sufficient in SDR-mediated splicing in transient expression and stable transformation systems. We also show prokaryote is incapable of SDR-mediated premRNA splicing.
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SOX2 modulates alternative splicing in transitional cell carcinoma.
Biochem. Biophys. Res. Commun.
PUBLISHED: 01-18-2010
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Aberrant alternative splicing of key cellular regulators may play a pivotal role in cancer development. To investigate the potential influence of altered alternative splicing on the development of transitional cell carcinoma (TCC), splicing activity in the TCC cell lines TSGH8301 and BFTC905 was examined using the SV40-immortalized uroepithelial cell line SV-HUC-1 as a reference. Our results indicate a significant alteration in splice site selection in the TCC cell lines. By gene expression profiling and subsequent validation, we discovered that sex-determining region Y-box protein 2 (SOX2) is specifically upregulated in BFTC905. Furthermore, ectopic expression of SOX2 modulates alternative splicing of the splicing reporter in vivo. More significantly, using an in vitro pull-down assay, it was found that SOX2 exhibits RNA-binding capability. Our observations suggest that SOX2 modulates alternative splicing by functioning as a splicing factor.
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[Ru/AC catalyzed ozonation of recalcitrant organic compounds].
Huan Jing Ke Xue
PUBLISHED: 11-26-2009
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Ozonation and Ru/AC catalyzed ozonation of dimethyl phthalate (DMP), phenols and disinfection by-products precursors were studied. It shows that Ru/AC catalyst can obviously enhance the mineralization of organic compounds. In the degradation of DMP, TOC removal was 28.84% by ozonation alone while it was 66.13% by catalytic ozonation. In the oxidation of 23 kinds of phenols, TOC removals were 9.57%-56.08% by ozonation alone while they were 41.81%-82.32% by catalytic ozonation. Compared to ozonation alone, Ru/AC catalyzed ozonation was more effective for the reduction of disinfection by-products formation potentials in source water. The reduction of haloacetic acids formation potentials was more obvious than thichlomethane formation potentials. After the treatment by catalytic ozonation, the haloacetic acids formation potentials decreased from 144.02 microg/L to 58.50 microg/L, which was below the standard value of EPA. However ozonation alone could not make it reach the standard. The treatments of source water by BAC, O3 + BAC, O3/AC + BAC and Ru/AC + O3 + BAC were also studied. In the four processes, TOC removal was 3.80%, 20.14%, 27.45% and 48.30% respectively, COD removal was 4.37%, 27.22%, 39.91% and 50.00% respectively, UV254 removal was 8.16%, 62.24%, 67.03% and 84.95% respectively. Ru/AC + O3 + BAC process is more effective than the other processes for the removal of TOC, COD and UV254 and no ruthenium leaching observed in the solution. It is a promising process for the treatment of micro polluted source water.
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[Distribution and molecular epidemiologic characterizes of insertion sequence IS1301 in neisseria meningitidis isolated from China].
Zhonghua Liu Xing Bing Xue Za Zhi
PUBLISHED: 10-06-2009
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To research the distribution and molecular epidemiology of insertion sequence IS1301 in Neisseria (N.) meningitidis strains in China, so as to provide scientific and available evidence for a new method of genotyping in N. meningitidis strains with IS1301.
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[Study of molecular subtypes of biotype 1A Yersinia enterocolitica in Shandong province from 2008 to 2009].
Zhonghua Yu Fang Yi Xue Za Zhi
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To investigate the molecular subtypes of 73 strains of Yersinia enterocolitica biotype 1A isolated in Shandong province by PFGE, and thereby to analyze the relationship between PFGE typing and biological characteristics.
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Knockout of the VPS22 component of the ESCRT-II complex in rice (Oryza sativa L.) causes chalky endosperm and early seedling lethality.
Mol. Biol. Rep.
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In both yeast and mammals, the major constituent of the endosomal sorting complex required for transport-II (ESCRT-II) is the VPS22/EAP30 protein, which plays an important role in ubiquitin-mediated degradation of membrane proteins through the multivesicular body pathway. However, the functions of ESCRT-II subunits in plants are largely unknown. In this work, we report the genetic analysis and phenotypic characterization of mutants in OsVPS22 gene, which encodes a functional VPS22 homolog in rice. On the basis of a collection of T-DNA lines, we identified a T-DNA insertion mutant, which showed abnormal segregation ratios; we then found that the T-DNA insertion is located within the sixth intron of the OsVPS22 gene. Compared with the wild type, this vps22 mutant exhibited seedling lethality and severe reduction in shoot and root growth. In addition, the vps22 mutant had a chalky endosperm in the grain. In summary, our data suggest that OsVPS22 may be required for seedling viability and grain filling in rice, thus providing a valuable resource for further exploration of the functions of the ESCRTing machinery in plants.
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[Diurnal variation and evaluation of water quality in different seasons of Panxi River in Chongqing].
Huan Jing Ke Xue
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Based on the investigation of water quality of Panxi River in different seasons, 2010, we assessed the diurnal variation of water quality in different seasons and the characteristics of water quality changes within a day by using non-parametric test, analysis of variance and grey relationship analysis. The results showed that the differences were not significant for Zn and Cu (P > 0.05), but significant differences existed among the pH, EC, DO, COD, TP, TSS, BOD5, NO(3-)-N, TN, NH(4+)-N, Pb and Cd contents. It showed that the minimum DO concentration occurred in winter, and the maximum of BOD5, COD and TOC concentrations occurred in winter, and the maximum NO(3-)-N concentration occurred in summer and the minimum TN, NH(4+)-N and TP concentrations occurred in summer. The diurnal variation of dissolved heavy metals showed relatively larger fluctuations in different seasons. The diurnal variation of different water quality parameters presented distinct patterns: diurnal variation of organic pollutants and nutrients showed the peak at 12:00 to 16:00 and dissolved heavy metals peaked at 12:00. The results of grey relationship analysis for surface water indicated that the water quality in spring was in the II class at 06:00 and 08:00 and was inferior to theV class for the rest hours; and the water quality in summer was in the II class; and the water quality in autumn was inferior to the V class at 06:00 and 16:00 and was in the II class for the rest hours; and the water quality in winter was in the II class at 08:00 and was inferior to the V class for the rest hours.
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A survey of urolithiasis in young children fed infant formula contaminated with melamine in two townships of Gansu, China.
Biomed. Environ. Sci.
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To determine the prevalence of urolithiasis in young children fed infant formula (IF) contaminated with melamine, and the association between IF consumption and urolithiasis.
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Different modulating effects of adenosine on neonatal and adult polymorphonuclear leukocytes.
ScientificWorldJournal
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Polymorphonuclear leukocytes (PMNs) are the major leukocytes in the circulation and play an important role in host defense. Intact PMN functions include adhesion, migration, phagocytosis, and reactive oxygen species (ROS) release. It has been known for a long time that adenosine can function as a modulator of adult PMN functions. Neonatal plasma has a higher adenosine level than that of adults; however, little is known about the modulating effects of adenosine on neonatal PMNs. The aim of this study was to investigate the effects of adenosine on neonatal PMN functions. We found that neonatal PMNs had impaired adhesion, chemotaxis, and ROS production abilities, but not phagocytosis compared to adult PMNs. As with adult PMNs, adenosine could suppress the CD11b expressions of neonatal PMNs, but had no significant suppressive effect on phagocytosis. In contrast to adult PMNs, adenosine did not significantly suppress chemotaxis and ROS production of neonatal PMNs. This may be due to impaired phagocyte reactions and a poor neonatal PMN response to adenosine. Adenosine may not be a good strategy for the treatment of neonatal sepsis because of impaired phagocyte reactions and poor response.
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[Diurnal variation and evaluation of water quality of Panxi River in spring].
Huan Jing Ke Xue
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Based on the investigation of water quality of Panxi River in spring, 2010, we assessed the diurnal variation of water quality in spring and the characteristics of water quality changes within a day by using non-parametric test, analysis of variance and grey relationship analysis. The results showed that the differences were not significant for t, DO, COD, Pb, Cd, Zn and Cu (P > 0.05) in upstream, midstream and downstream, but significant difference existed among the pH, EC, TP, TSS, BOD5, NO3(-) -N, TN and NH4(+) -N contents. The diurnal variation of different water quality parameters presented distinct patterns: TN, TP and EC increased wavelike with time in upstream, fluctuated less in middle and showed the "single-peak single-valley" pattern in downstream, with the peak at 12:00. The diurnal variation of COD showed that "single-peak" pattern and with the peak at 10:00 in upstream and midstream and peak at 12:00 in downstream. The concentrations of Pb, Cd, Zn and Cu were low and peak at 12:00 in midstream; The grey relationship analysis indicated that the water quality in upstream was inferior to the V class of surface water at 18:00 and 20:00 and were in the II class of surface water for the rest hours, and the water quality in midstream was inferior to the V class of surface water at 12:00 and were in the II class of surface water for the rest hours; and the water quality in downstream was inferior to the V class of surface water all time during investigation.
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[Characterization and source apportionment of pollutants in urban roadway runoff in Chongqing].
Huan Jing Ke Xue
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By investigating surface runoff from urban roadway in Chongqing, we assessed the characteristics of surface runoff pollution and the effect of rainfall intensity and antecedent dry weather period on water quality. Using multivariate statistical analysis of data of runoff quality, potential pollutants discharged from urban roadway runoff were identified. The results show that the roadway runoff has high levels of COD, TP and TN, the EMC were 60.83-208.03 mg x L(-1), 0.47-1.01 mg x L(-1) and 2.07-5.00 mg x L(-1) respectively, being the main pollutants; The peaks of pollutant concentration are ahead of or synchronous with the peak of runoff volume; the peaks of pollutant concentrations are mostly occurred within 10 minutes of rainfall. The heavy metal concentrations fluctuate dentately during runoff proceeding. Two potential pollution sources to urban roadway runoff apportioned by using principal component analysis are: vehicles traffic loss and atmospheric dry and wet deposition, and municipal wastes.
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[Research on evaluation of water quality of Beijing urban stormwater runoff].
Huan Jing Ke Xue
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The natural rainwater and stormwater runoff samples from three underlying surfaces (rooftop, campus road and ring road) were sampled and analyzed from July to October, 2010 in Beijing. Eight rainfall events were collected totally and thirteen water quality parameters were measured in each event. Grey relationship analysis and principal component analysis were applied to assess composite water quality and identify the main pollution sources of stormwater runoff. The results show that the composite water quality of ring road runoff is mostly polluted, and then is rooftop runoff, campus road runoff and rainwater, respectively. The composite water quality of ring road runoff is inferior to V class of surface water, while rooftop runoff, campus road runoff and rainwater are in II class of surface water. The mean concentration of TN and NH4(+)-N in rainwater and runoff is 5.49-11.75 mg x L(-1) and 2.90-5.67 mg x L(-1), respectively, indicating that rainwater and runoff are polluted by nitrogen (N). Two potential pollution sources are identified in ring road runoff: (1) P, SS and organic pollutant are possibly related to debris which is from vehicle tyre and material of ring road; (2) N and dissolved metal have relations with automobile exhaust emissions and bulk deposition.
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Authentication of Angelica anomala Avé-Lall cultivars through DNA barcodes.
Mitochondrial DNA
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Angelica anomala Avé-Lall (Chuanbaizhi in Chinese) is an important medicinal plant which can be used in traditional Chinese medicines; however, there are no authentic and universal methods to differentiate this Sichuan famous-region drug of A. anomala from a large number of non-famous-region and false drugs. It has been demonstrated that DNA barcoding is a molecular diagnostic method for species identification, which uses a single standardized DNA fragment. In this study, we tested five DNA barcoding candidates (matK, ITS, ITS2, rbcL, and psbA-trnH), and we found that ITS was the best candidate to authenticate the famous-region drug of A. anomala. Moreover, through comparative analysis of these five DNA barcodes between A. anomala and Angelica dahurica, we found that ITS had the most and ITS2 had more variable regions, but the psbA-trnH, rbcL, and matK regions were identical. Hence, we suggest ITS as the DNA barcoding to identify A. anomala and A. dahurica. Moreover, we are determined to adopt the A. anomala as the accurate Latin name of Chuanbaizhi.
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What is Visualize?

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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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.