JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Do Physical Activity, Smoking, Drinking, or Depression Modify Transitions from Cognitive Impairment to Functional Disability?
J. Alzheimers Dis.
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
Background: Individual-level modifiers can delay onset of limitations in basic activities of daily living (ADLs) among cognitively impaired individuals. We assessed whether these modifiers also delayed onset of limitations in instrumental ADLs (IADLs) among individuals at elevated dementia risk. Objectives: To determine whether modifiable individual-level factors delay incident IADL limitations among adults stratified by dementia risk. Methods: Health and Retirement Study participants aged 65+ without activity limitations in 1998 or 2000 (n = 5,219) were interviewed biennially through 2010. Dementia probability, categorized in quartiles, was used to predict incident IADL limitations with Poisson regression. We estimated relative (risk ratio) and absolute (number of limitations) effects from models including dementia, individual-level modifiers (physical inactivity, smoking, no alcohol consumption, and depression) and interaction terms between dementia and individual-level modifiers. Results: Dementia probability quartile predicted incident IADL limitations (relative risk for highest versus lowest quartile = 0.44; 95% CI: 0.28-0.70). Most modifiers did not significantly increase risk of IADL limitations among the cognitively impaired. Physical inactivity (RR = 1.60; 95% CI: 1.16, 2.19) increased the risk of IADL limitations among the cognitively impaired. The interaction between physical inactivity and low dementia probability was statistically significant (p = 0.009) indicating that physical inactivity had significantly larger effects on incident IADLs among cognitively normal than among those with high dementia probability. Conclusion: Physical activity may protect against IADL limitations while smoking, alcohol consumption, and depression do not afford substantial protection among the cognitively impaired. Results highlight the need for extra support for IADLs among individuals with cognitive losses.
Related JoVE Video
Facile and Universal Superhydrophobic Modification to Fabricate Water-borne, Multifunctional Nacre-Mimetic Films with Excellent Stability.
ACS Appl Mater Interfaces
PUBLISHED: 11-07-2014
Show Abstract
Hide Abstract
Although numerous kinds of water-borne, nacre-mimetic films with excellent properties have been fabricated via different assembly methods, it remains difficult to put those kinds of lightweight materials into practical applications because they are sensitive to water in the environment. Herein, a simple superhydrophobic modification method was used to enhance the repellency of film to water and/or corrosive liquids in the environment. Furthermore, it lowered the gas transmission rate of the films dramatically and improved the heat and flame shield capabilities. This approach could also be applied to other kinds of nacre-mimetic films, proving a versatile, low-cost, fast, and facile method to produce large area and thick, water-borne, multifunctional films with excellent repellency to water and some corrosive liquids in the environment, which will pave the road for the nacre-mimetic films to practical applications.
Related JoVE Video
Phylogenomics resolves the timing and pattern of insect evolution.
Bernhard Misof, Shanlin Liu, Karen Meusemann, Ralph S Peters, Alexander Donath, Christoph Mayer, Paul B Frandsen, Jessica Ware, Tomáš Flouri, Rolf G Beutel, Oliver Niehuis, Malte Petersen, Fernando Izquierdo-Carrasco, Torsten Wappler, Jes Rust, Andre J Aberer, Ulrike Aspöck, Horst Aspöck, Daniela Bartel, Alexander Blanke, Simon Berger, Alexander Böhm, Thomas R Buckley, Brett Calcott, Junqing Chen, Frank Friedrich, Makiko Fukui, Mari Fujita, Carola Greve, Peter Grobe, Shengchang Gu, Ying Huang, Lars S Jermiin, Akito Y Kawahara, Lars Krogmann, Martin Kubiak, Robert Lanfear, Harald Letsch, Yiyuan Li, Zhenyu Li, Jiguang Li, Haorong Lu, Ryuichiro Machida, Yuta Mashimo, Pashalia Kapli, Duane D McKenna, Guanliang Meng, Yasutaka Nakagaki, José Luis Navarrete-Heredia, Michael Ott, Yanxiang Ou, Günther Pass, Lars Podsiadlowski, Hans Pohl, Björn M von Reumont, Kai Schütte, Kaoru Sekiya, Shota Shimizu, Adam Slipinski, Alexandros Stamatakis, Wenhui Song, Xu Su, Nikolaus U Szucsich, Meihua Tan, Xuemei Tan, Min Tang, Jingbo Tang, Gerald Timelthaler, Shigekazu Tomizuka, Michelle Trautwein, Xiaoli Tong, Toshiki Uchifune, Manfred G Walzl, Brian M Wiegmann, Jeanne Wilbrandt, Benjamin Wipfler, Thomas K F Wong, Qiong Wu, Gengxiong Wu, Yinlong Xie, Shenzhou Yang, Qing Yang, David K Yeates, Kazunori Yoshizawa, Qing Zhang, Rui Zhang, Wenwei Zhang, Yunhui Zhang, Jing Zhao, Chengran Zhou, Lili Zhou, Tanja Ziesmann, Shijie Zou, Yingrui Li, Xun Xu, Yong Zhang, Huanming Yang, Jian Wang, Jun Wang, Karl M Kjer, Xin Zhou.
Science
PUBLISHED: 11-06-2014
Show Abstract
Hide Abstract
Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relations hips. We dated the origin of insects to the Early Ordovician [~479 million years ago (Ma)], of insect flight to the Early Devonian (~406 Ma), of major extant lineages to the Mississippian (~345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects.
Related JoVE Video
Epigallocatechin-3-gallate (EGCG) inhibits 3-hydroxy-3-methylglutaryl-CoA reductase in the presence of glycerol.
Pak J Pharm Sci
PUBLISHED: 11-03-2014
Show Abstract
Hide Abstract
The inhibition of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCR) is considered able to decrease serum cholesterol levels and dramatically reduce the risk for cardiovascular and cerebrovascular diseases. The statins, competitive inhibitors of HMGCR, have been employed to control hypercholesterolemia. But their side effects, especially their safety of long-term administration have attracted great attention. Therefore, there is still an urgent requirement for the development of safer inhibitors of HMGCR with less serious side effects. In this study, we cloned and purified the catalytic domain of human HMGCR (?HMGCR), and applied the method of Ultra Performance Liquid Chromatography (UPLC) to assay ?HMGCR activity and screen its inhibitors from natural products. The results indicated that EGCG can inhibit ?HMGCR in the presence of some glycerol in vitro and can decrease cellular total cholesterol in HepG2 cells. As a consequence, it is promising to put EGCG into the development of hypolipidemic health product.
Related JoVE Video
Identification of chemokine receptors as potential modulators of endocrine resistance in estrogen receptor positive breast cancers.
Breast Cancer Res.
PUBLISHED: 10-31-2014
Show Abstract
Hide Abstract
IntroductionEndocrine therapies target estrogenic stimulation of breast cancer (BC) growth but resistance remains problematic. Our aims were 1) to identify genes most strongly associated with resistance to endocrine therapy by intersecting global gene transcription data from patients treated presurgically with the aromatase inhibitor anastrazole with those from MCF7 cells adapted to long-term estrogen deprivation (LTED); 2) to assess the clinical value of selected genes in public clinical data sets; 3) to determine the impact of targeting these genes with novel agents.MethodsGene expression and Ki67 data were available from 69 postmenopausal women with estrogen receptor positive (ER+) early BC, at baseline and 2-weeks post anastrazole treatment and from cell lines adapted to LTED. Functional consequence of target genes on proliferation, ER-mediated transcription and downstream cell signaling were assessed.ResultsIntersection of genes predicting for a poor change in Ki67, with those up-regulated in LTED cells, identified 32 genes strongly correlated with poor antiproliferative response, which were associated with inflammation/immunity. In a panel of LTED cell lines, C-X-C chemokine receptor type 7 (CXCR7) and CXCR4 were upregulated compared to their wild-types (wt), CXCR7 but not CXCR4 associated with reduced relapse free survival in ER¿+¿BC patients. In wt-SUM44, wt-MCF7 and their LTED derivatives, siCXCR4 had no specific effect on their proliferation. In contrast, siCXCR7 and CCX733, a CXCR7 antagonist specifically suppressed proliferation of MCF7-LTED cells. SiCXCR7 suppressed proteins associated with G1-S transition and inhibited ER-transactivation in MCF7-LTED but not wt-MCF7 by impeding association between ER and proline, glutamic acid and leucine rich protein 1 (PELP1), an ER coactivator.ConclusionThese data highlight CXCR7 as a potential therapeutic target, warranting clinical investigation in endocrine resistant BC.
Related JoVE Video
Methylation of miR-129-5p CpG island modulates multi-drug resistance in gastric cancer by targeting ABC transporters.
Oncotarget
PUBLISHED: 10-27-2014
Show Abstract
Hide Abstract
Recent studies have reported that hyper-methylation in the promoter region of miRNAs could silence the expression of tumor suppressive miRNAs and might play significant roles in the process of tumor development. However, the potential mechanisms regarding how methylation of miRNA CpG Island could regulate cancer cell chemo-resistance have not yet been studied. Using microarray and BSP (Bisulfate Sequencing PCR) assays, we found that compared with the parent SGC7901/VCR cells, expression of miR-129-5p was restored in SGC7901/VCR gastric cancer multi-drug resistant cell line treated by de-methylation reagent (5-AZA-dC). Using gain or loss of function assays, we found the over-expressed miR-129-5p reduced the chemo-resistance of SGC7901/VCR and SGC7901/ADR cells, while down-regulation of miR-129-5p had an opposite effect. Furthermore, three members of multi-drug resistance (MDR) related ABC transporters (ABCB1, ABCC5 and ABCG1) were found to be direct targets of miR-129-5p using bioinformatics analysis and report gene assays. The present study indicated that hyper-methylation of miR-129-5p CpG island might play important roles in the development of gastric cancer chemo-resistance by targeting MDR related ABC transporters and might be used as a potential therapeutic target in preventing the chemo-resistance of gastric cancer.
Related JoVE Video
Increasing the response rate of text messaging data collection: a delayed randomized controlled trial.
J Am Med Inform Assoc
PUBLISHED: 10-22-2014
Show Abstract
Hide Abstract
To test the effectiveness of multiple interventions on increasing the response rate of text messaging for longitudinal data collection.
Related JoVE Video
Transcriptional profiling reveals crosstalk between mesenchymal stem cells and endothelial cells promoting pre-vascularization by reciprocal mechanisms.
Stem Cells Dev.
PUBLISHED: 10-10-2014
Show Abstract
Hide Abstract
Mesenchymal stem cells (MSCs) show great promise in blood vessel restoration and vascularization enhancement in many therapeutic situations. Typically, the co-implantation of MSCs with vascular endothelial cells (ECs) is effective for the induction of functional vascularization in vivo, indicating its potential applications in regenerative medicine. The effects of MSCs-ECs-induced vascularization can be modeled in vitro, providing simplified models for understanding their underlying communication. In this paper, a contact co-culture model in vitro and an RNA-seq approach were employed to reveal the active crosstalk between MSCs and ECs within a short time period at both morphological and transcriptional levels. The RNA-seq results suggested that angiogenic genes were significantly induced upon co-culture, and this pre-vascularization commitment might require the NF-?B signaling. NF-?B blocking and interleukin neutralization experiments demonstrated that MSCs potentially secreted interleukin factors including IL1? and IL6 to modulate NF-?B signaling as well as downstream chemokines during co-culture. Conversely, RNA-seq results indicated that the MSCs were regulated by the co-culture environment to a smooth muscle commitment within this short period, which largely induced myocardin, the myogenic co-transcriptional factor. These findings demonstrate the mutual molecular mechanism of MSCs-ECs-induced pre-vascularization commitment in a quick response.
Related JoVE Video
Multiplex sequencing of pooled mitochondrial genomes-a crucial step toward biodiversity analysis using mito-metagenomics.
Nucleic Acids Res.
PUBLISHED: 10-09-2014
Show Abstract
Hide Abstract
The advent in high-throughput-sequencing (HTS) technologies has revolutionized conventional biodiversity research by enabling parallel capture of DNA sequences possessing species-level diagnosis. However, polymerase chain reaction (PCR)-based implementation is biased by the efficiency of primer binding across lineages of organisms. A PCR-free HTS approach will alleviate this artefact and significantly improve upon the multi-locus method utilizing full mitogenomes. Here we developed a novel multiplex sequencing and assembly pipeline allowing for simultaneous acquisition of full mitogenomes from pooled animals without DNA enrichment or amplification. By concatenating assemblies from three de novo assemblers, we obtained high-quality mitogenomes for all 49 pooled taxa, with 36 species >15 kb and the remaining >10 kb, including 20 complete mitogenomes and nearly all protein coding genes (99.6%). The assembly quality was carefully validated with Sanger sequences, reference genomes and conservativeness of protein coding genes across taxa. The new method was effective even for closely related taxa, e.g. three Drosophila spp., demonstrating its broad utility for biodiversity research and mito-phylogenomics. Finally, the in silico simulation showed that by recruiting multiple mito-loci, taxon detection was improved at a fixed sequencing depth. Combined, these results demonstrate the plausibility of a multi-locus mito-metagenomics approach as the next phase of the current single-locus metabarcoding method.
Related JoVE Video
An ab initio molecular dynamics study of thermal decomposition of 3,6-di(azido)-1,2,4,5-tetrazine.
Phys Chem Chem Phys
PUBLISHED: 09-08-2014
Show Abstract
Hide Abstract
Ab initio molecular dynamics simulations were performed to study the thermal decomposition of isolated and crystal 3,6-di(azido)-1,2,4,5-tetrazine (DiAT). During unimolecular decomposition, the three different initiation mechanisms were observed to be N-N2 cleavage, ring opening, and isomerization, respectively. The preferential initial decomposition step is the homolysis of the N-N2 bond in the azido group. The release mechanisms of nitrogen gas are found to be very different in the early and later decomposition stages of crystal DiAT. In the early decomposition, DiAT decomposes very fast and drastically without forming any stable long-chains or heterocyclic clusters, and most of the nitrogen gases are released through rapid rupture of nitrogen-nitrogen and carbon-nitrogen bonds. But in the later decomposition stage, the release of nitrogen gas is inhibited due to low mobility, long distance from each other, and strong carbon-nitrogen bonds. To overcome the obstacles, the nitrogen gases are released through slow formation and disintegration of polycyclic networks. Our simulations suggest a new decomposition mechanism for the organic polyazido initial explosive at the atomistic level.
Related JoVE Video
FLA8/KIF3B phosphorylation regulates kinesin-II interaction with IFT-B to control IFT entry and turnaround.
Dev. Cell
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
The assembly and maintenance of cilia depends on intraflagellar transport (IFT). Activated IFT motor kinesin-II enters the cilium with loaded IFT particles comprising IFT-A and IFT-B complexes. At the ciliary tip, kinesin-II becomes inactivated, and IFT particles are released. Moreover, the rate of IFT entry is dynamically regulated during cilium assembly. However, the regulatory mechanism of IFT entry and loading/unloading of IFT particles remains elusive. We show that the kinesin-II motor subunit FLA8, a homolog of KIF3B, is phosphorylated on the conserved S663 by a calcium-dependent kinase in Chlamydomonas. This phosphorylation disrupts the interaction between kinesin-II and IFT-B, inactivates kinesin-II and inhibits IFT entry, and is also required for IFT-B unloading at the ciliary tip. Furthermore, our data suggest that the IFT entry rate is controlled by regulation of the cellular level of phosphorylated FLA8. Therefore, FLA8 phosphorylation acts as a molecular switch to control IFT entry and turnaround.
Related JoVE Video
Searching for a new family of insensitive high explosives by introducing N hybridization and N-oxides into a cage cubane.
J Mol Model
PUBLISHED: 08-26-2014
Show Abstract
Hide Abstract
A new family of energetic azacubane N-oxides were designed by introducing N-oxides into azacubanes and investigated by using density functional theory. Introducing the N-oxides into the azacubanes could improve their detonation performance significantly due to the increase of the OB and ? but would also increase the sensitivity to some extent. These effects would be further enhanced as the numbers of N-oxides increase. Among all the designed azacubane N-oxides, D6-4 (1,3,5,7-tetraazacubane-1,3,5,7-tetraoxides) has higher detonation performance than one famous high explosive HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazocane) and lower sensitivity than one very insensitive explosive TNT (1-methyl-2,4,6-trinitrobenzene), suggesting that its overall performance is outstanding and may be considered as the potential candidate of insensitive high explosives. The internal small cage C-N skeleton of D6-4 is surrounded by the external big cage hydrogen bonds and this special double cage structure may be an important reason why it has low sensitivity.
Related JoVE Video
[RNAi-mediated silencing of CD147 inhibits the proliferation and infiltrations of leukemic cells SHI-1].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 08-26-2014
Show Abstract
Hide Abstract
To investigate the role of CD147 gene on the proliferation and infiltration of a human monocytic leukemic cell line SHI-1.
Related JoVE Video
Co-administration of Wuzhi capsules and tacrolimus in patients with idiopathic membranous nephropathy: clinical efficacy and pharmacoeconomics.
Int Urol Nephrol
PUBLISHED: 08-22-2014
Show Abstract
Hide Abstract
Tacrolimus is an effective (but relatively expensive) immunosuppressant that is used widely in patients with membranous nephropathy. To reduce the tacrolimus dose while maintaining an equivalent therapeutic effect, we studied the clinical efficacy and pharmacoeconomic impact of co-administration of Wuzhi capsules (WZC that protects against damage to liver cells) and tacrolimus.
Related JoVE Video
Bimodal-hybrid heterocyclic amine targeting oxidative pathways and copper mis-regulation in Alzheimer's disease.
Metallomics
PUBLISHED: 08-22-2014
Show Abstract
Hide Abstract
Oxidative stress resulting from metal-ion misregulation plays a role in the development of Alzheimer's disease (AD). This process includes the production of tissue-damaging reactive oxygen species and amyloid aggregates. Herein we describe the synthesis, characterization and protective capacity of the small molecule, lipoic cyclen, which has been designed to target molecular features of AD. This construct utilizes the biologically compatible and naturally occurring lipoic acid as a foundation for engendering low cellular toxicity in multiple cell lines, radical scavenging capacity, tuning the metal affinity of the parent cyclen, and results in an unexpected affinity for amyloid without inducing aggregation. The hybrid construct thereby shows protection against cell death induced by amyloid aggregates and copper ions. These results provide evidence for the rational design methods used to produce this fused molecule as a potential strategy for the development of lead compounds for the treatment of neurodegenerative disorders.
Related JoVE Video
Arene ruthenium(ii) complex, a potent inhibitor against proliferation, migration and invasion of breast cancer cells, reduces stress fibers, focal adhesions and invadopodia.
Metallomics
PUBLISHED: 08-21-2014
Show Abstract
Hide Abstract
Effective chemotherapy drugs for cancer that would inhibit tumor growth and suppress metastasis are currently lacking. In this study, a series of arene ruthenium complexes, [(?(6)-arene)Ru(H2iip)Cl]Cl (arene = p-cymene, ; CH3C6H5, ; and C6H6, ), were synthesized and their inhibitory activity against tumor cells were evaluated. The results showed that the complex inhibited the growth of MDA-MB-231 breast cancer cells by inducing S-phase arrest, which is closely related to the inhibition of cell mitosis-mediated cell nucleus damage. Further studies showed that can inhibit the invasion and metastasis of MDA-MB-231 cells. The morphology of MDA-MB-231 cells changed, the number of focal adhesions decreased, and the stress fibers de-polymerized upon dealing with the complex . The FITC-gelatin assay confirmed that the formation of invadopodia in MDA-MB-231 cells was significantly blocked by . Furthermore, can block the AKT signal pathway by upregulating the PTEN expression through binding and downregulating miR-21. These results demonstrated that this type of arene ruthenium(ii) complex can block the invadopodia formation by regulating the PTEN/AKT signal pathway mediated by miR-21 to inhibit the invasion and metastasis of breast cancer cells. Therefore, this complex can be used as a potential dual functional agent to inhibit the growth and metastasis of tumor cells.
Related JoVE Video
Possible correlation of selenoprotein w with inflammation factors in chicken skeletal muscles.
Biol Trace Elem Res
PUBLISHED: 08-16-2014
Show Abstract
Hide Abstract
The aim of the present study was to investigate the possible correlation of selenoprotein W (SelW) with inflammatory injury induced by dietary selenium (Se) deficiency in chicken. One-day-old male chickens were fed either a commercial diet or a Se-deficient diet for 55 days. Then, the expression levels of SelW messenger RNA (mRNA) and inflammation-related genes (NF-?B, TNF-?, iNOS, COX-2, and PTGES) in chicken skeletal muscles (wing muscle, pectoral muscle, and thigh muscle) were determined at 15, 25, 35, 45, and 55 days old, respectively. In addition, the correlation between SelW mRNA expression and inflammation-related genes were assessed. The results showed that dietary Se deficiency reduced the mRNA expression of SelW in chicken wing, pectorals, and thigh muscles. In contrast, Se deficiency increased the mRNA expression levels of inflammation-related genes in chicken skeletal muscle tissues at different time points. The Pearson's correlation coefficients showed that the mRNA expression levels of inflammation-related genes were significantly negative related to SelW (p?
Related JoVE Video
Ultrasound assisted morphological control of mesoporous silica with improved lysozyme adsorption.
Ultrason Sonochem
PUBLISHED: 08-15-2014
Show Abstract
Hide Abstract
The morphological control of mesoporous silica without any additives has attracted much attention. Discrete rod-like and string-of-beads like mesoporous SBA-15 can be achieved under ultrasound irradiation without changing the composition of synthesis system. The smaller particles of SBA-15 showed improved lysozyme immobilization capacity and higher adsorption rate over conventional rope-like SBA-15.
Related JoVE Video
Age-dependent expression of duodenal cytochrome B561, divalent metal transporter 1, ferroportin 1 and hephaestin in the duodenum of rats.
J. Gastroenterol. Hepatol.
PUBLISHED: 08-12-2014
Show Abstract
Hide Abstract
The body's requirement for iron is different at different developmental stages. However, the molecular mechanisms of age-dependent iron metabolism are poorly understood. In the present study, we investigated the expression of iron transport proteins in the duodenum of Sprague-Dawley (SD) rats at five different age stages.
Related JoVE Video
Helicobacter pylori promotes VEGF expression via the p38 MAPK?mediated COX?2?PGE2 pathway in MKN45 cells.
Mol Med Rep
PUBLISHED: 08-06-2014
Show Abstract
Hide Abstract
Helicobacter pylori has been suggested to be the major cause of gastric malignancy. However, the pathogenesis and molecular mechanisms of gastric tumorigenesis induced by H. pylori infection are yet to be elucidated. In the present study, the expression levels of vascular endothelial growth factor (VEGF), which has been suggested to promote angiogenesis in gastric cancer, were found to be elevated in H. pylori-infected MKN45 cells. Furthermore, it was demonstrated that the expression of VEGF was modulated by the p38 mitogen-activated protein kinases (MAPK) pathway via regulation of the cyclooxygenase (COX)-2 pathway. It was also found that prostaglandin E2 (PGE2) and its receptor EP2/EP4 may mediate the upregulation of VEGF in gastric cells exposed to H. pylori. In combination, these results suggest that VEGF expression is regulated by the p38 MAPK COX?2-PGE2-EP2/EP4 pathway in gastric cancer cells induced by H. pylori. This provides a theoretical basis for the investigation of the pathogenesis of H. pylori?induced gastric cancer.
Related JoVE Video
Mixed-ligand ruthenium polypyridyl complexes as apoptosis inducers in cancer cells, the cellular translocation and the important role of ROS-mediated signaling.
Dalton Trans
PUBLISHED: 08-05-2014
Show Abstract
Hide Abstract
Ruthenium (Ru) polypyridyl complexes have emerged as leading players among the potential metal-based candidates for cancer treatment. However, the roles of cellular translocation in their action mechanisms remain elusive. Herein we present the synthesis and characterization of a series of ruthenium (Ru) complexes containing phenanthroline derivatives with varying lipophilicities, and examine their mechanism of anticancer action. Results showed that increasing the lipophilicity of complexes can enhance the rates of cellular uptake. The in vitro anticancer efficacy of these complexes depended on the levels of ROS overproduction, rather than on cellular Ru uptake levels. The introduction of a phenolic group on the ligand effectively enhanced their intracellular ROS generation and anticancer activities. In particular, complex , with an ortho-phenolic group on the ligand, exhibited better selectivity between cancer and normal cells in comparison with cisplatin. Notably, complex entered the cancer cells partially through transferrin receptor-mediated endocytosis, and then it translocated from lysosomes to the mitochondria, where it activated mitochondrial dysfunction by regulation of Bcl-2 family proteins, thus leading to intracellular ROS overproduction. Excess ROS amplified apoptotic signals by activating many downstream pathways such as p53 and MAPK pathways to promote cell apoptosis. Overall, this study provides a drug design strategy for discovery of Ru-based apoptosis inducers, and elucidates the intracellular translocation of these complexes.
Related JoVE Video
Hypomethylation at the regulatory T cell-specific demethylated region in CD25hi T cells is decoupled from FOXP3 expression at the inflamed site in childhood arthritis.
J. Immunol.
PUBLISHED: 08-04-2014
Show Abstract
Hide Abstract
The maintenance of FOXP3 expression in CD25(hi) regulatory T cells (Tregs) is crucial to the control of inflammation and essential for successful Treg transfer therapies. Coexpression of CD25 and FOXP3 in combination with a hypomethylated region within the FOXP3 gene, called the Treg-specific demethylated region (TSDR), is considered the hallmark of stable Tregs. The TSDR is an epigenetic motif that is important for stable FOXP3 expression and is used as a biomarker to measure Treg lineage commitment. In this study, we report that, unlike in peripheral blood, CD4(+) T cell expression of CD25 and FOXP3 is frequently dissociated at the inflamed site in patients with juvenile idiopathic arthritis, which led us to question the stability of human Tregs in chronic inflammatory environments. We describe a novel CD4(+)CD127(lo)CD25(hi) human T cell population that exhibits extensive TSDR and promoter demethylation in the absence of stable FOXP3 expression. This population expresses high levels of CTLA-4 and can suppress T conventional cell proliferation in vitro. These data collectively suggest that this population may represent a chronically activated FOXP3(lo) Treg population. We show that these cells have defects in IL-2 signaling and reduced expression of a deubiquitinase important for FOXP3 stability. Clinically, the proportions of these cells within the CD25(hi) T cell subset are increased in patients with the more severe courses of disease. Our study demonstrates, therefore, that hypomethylation at the TSDR can be decoupled from FOXP3 expression in human T cells and that environment-specific breakdown in FOXP3 stability may compromise the resolution of inflammation in juvenile idiopathic arthritis.
Related JoVE Video
Poor infant and young child feeding practices and sources of caregivers' feeding knowledge in rural Hebei Province, China: findings from a cross-sectional survey.
BMJ Open
PUBLISHED: 08-01-2014
Show Abstract
Hide Abstract
To obtain a general overview of infant and young child feeding practices in one rural county in China and identify current delivery channels and challenges.
Related JoVE Video
Long-range, high-precision absolute distance measurement based on two optoelectronic oscillators.
Opt Lett
PUBLISHED: 08-01-2014
Show Abstract
Hide Abstract
We demonstrate a scheme for long-range, high-precision absolute distance measurement based on frequency detection using two optoelectronic oscillators to convert distance information to frequency information. The two-oscillator design offers the unique advantage of self-referencing. By taking advantage of the accumulative magnification theory, the error of the measured distance is decreased by approximately 10? fold, which significantly improves the precision of the measured distance. In our experiments, the maximum error is ±1.5???m at an emulated distance of approximately 3.35 km, including a drift error of approximately 1 ?m in the air path due to the variation of environmental conditions. The highest relative measurement precision achieved in our current system is 4.5×10?¹?.
Related JoVE Video
Spectroscopic analyses and studies on respective interaction of cyanuric acid and uric acid with bovine serum albumin and melamine.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 07-30-2014
Show Abstract
Hide Abstract
In this work, the fluorescence quenching was used to study the interaction of cyanuric acid (CYA) and uric acid (UA) with bovine serum albumin (BSA) at two different temperatures (283 K and 310 K). The bimolecular quenching constant (Kq), apparent quenching constant (Ksv), effective binding constant (KA) and corresponding dissociation constant (KD), binding site number (n) and binding distance (r) were calculated by adopting Stern-Volmer, Lineweaver-Burk, Double logarithm and overlap integral equations. The results show that CYA and UA are both able to obviously bind to BSA, but the binding strength order is BSA+CYA
Related JoVE Video
Genome Sequence of Borrelia garinii Strain SZ, Isolated in China.
Genome Announc
PUBLISHED: 07-19-2014
Show Abstract
Hide Abstract
We announce the genome sequence of Borrelia garinii strain SZ, isolated from Dermacentor ticks collected in northeastern China. B. garinii strain SZ carries numerous plasmids, both 10 circular and 9 linear plasmids. The 902,487-bp linear chromosome (28.2% GC content) contains 820 open reading frames, 33 tRNAs, and 4 complete rRNAs. The plasmid cp32-10 contains one clustered regularly interspaced short palindromic repeat (CRISPR) with four repeats.
Related JoVE Video
Spatial and vertical variations of perfluoroalkyl substances in sediments of the Haihe River, China.
J Environ Sci (China)
PUBLISHED: 07-05-2014
Show Abstract
Hide Abstract
The levels of six perfluoroalkyl substances (PFASs) in surface sediment and their vertical variations in dated sediment cores from the Haihe River were investigated; studied substances included perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnA), and perfluorododecanoic acid (PFDoA). Results showed that the total PFAS concentration in surface sediment ranged between 0.52 and 16.33 ng/g dry weight (dw) with an average of 3.47 ng/g dw, with PFOS and PFOA as the dominant PFASs. In general, the PFAS concentrations in the mainstream increased from the upper to the lower reaches, except that a drop occurred downstream of the Erdao dam. Although the PFASs in the sediment cores did not show a clear decreasing or increasing trend with depth, the three cores had a similar vertical variation. The PFAS levels were relatively low in the surface sediment, and reached the first high point at 8-20 cm as a result of the wide use of PFASs from 1990 to 2000. After that the PFAS levels decreased, and then increased to a second high point at about 40-48 cm, which might be caused by the leaching of PFASs in sediment. Because PFASs have hydrophilic groups and relatively high solubility, the PFASs will transfer from the upper to lower layers of sediment when water infiltration occurs, leading to the fluctuation of PFAS levels in sediment cores. This study suggests that both the temporal variation of sources and transfer processes of PFASs in sediments are important factors influencing the vertical variation of PFASs in sediment cores.
Related JoVE Video
Production of accelerating quad Airy beams and their optical characteristics.
Opt Express
PUBLISHED: 07-01-2014
Show Abstract
Hide Abstract
Based on a geometric caustic argument and diffraction catastrophe theory, we generate a novel form of accelerating beams using a symmetric 3/2 phase-only pattern. Such beams can be called accelerating quad Airy beams (AQABs) because they look very much like four face-to-face combined Airy beams. Optical characteristics of AQABs are subsequently investigated. The research results show that the beams have axial-symmetrical and centrosymmetrical transverse intensity patterns and quasi-diffraction-free propagation features for their four main lobes while undergoing transverse shift along parabolic trajectories. Moreover, we also demonstrate that AQABs possess self-construction ability when local areas are blocked. The unique optical properties of these beams will make them useful tools for future scientific applications.
Related JoVE Video
A test data compression scheme based on irrational numbers stored coding.
ScientificWorldJournal
PUBLISHED: 06-27-2014
Show Abstract
Hide Abstract
Test question has already become an important factor to restrict the development of integrated circuit industry. A new test data compression scheme, namely irrational numbers stored (INS), is presented. To achieve the goal of compress test data efficiently, test data is converted into floating-point numbers, stored in the form of irrational numbers. The algorithm of converting floating-point number to irrational number precisely is given. Experimental results for some ISCAS 89 benchmarks show that the compression effect of proposed scheme is better than the coding methods such as FDR, AARLC, INDC, FAVLC, and VRL.
Related JoVE Video
Quantum chemical studies on three novel 1,2,4-triazole N-oxides as potential insensitive high explosives.
J Mol Model
PUBLISHED: 06-27-2014
Show Abstract
Hide Abstract
Three novel explosives were designed by introducing N-oxides into 1,2,4-triazole: 1-amino-3,5-dinitro-1,2,4-triazole-2?N-oxide (ADT2NO), 1-amino-2,5-dinitro-1,2,4-triazole-3?N-oxide (ADT3NO), and 1-amino-3,5-dinitro-1,2,4-triazole-4?N-oxide (ADT4NO). Their detonation performance and sensitivity were estimated by using density functional theory and compared with some famous explosives like 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) and 1-methyl-2,4,6-trinitrobenzene (TNT). All three designed molecules are more powerful than HMX and less sensitive than TNT, indicating that ADT2NO, ADT3NO, and ADT4NO have high detonation performance as HMX and low sensitivity as TNT, making them being very valuable and may be considered as the potential candidates of insensitive high explosives. Properly introducing N-oxides into the energetic triazole derivatives can generate some superior energetic compounds with both high explosive performance and reduced sensitivity.
Related JoVE Video
Chemical characteristics of size-resolved aerosols in winter in Beijing.
J Environ Sci (China)
PUBLISHED: 06-23-2014
Show Abstract
Hide Abstract
Size-resolved aerosols were continuously collected by a Nano Sampler for 13 days at an urban site in Beijing during winter 2012 to measure the chemical composition of ambient aerosol particles. Data collected by the Nano Sampler and an ACSM (Aerodyne Aerosol Chemical Speciation Monitor) were compared. Between the data sets, similar trends and strong correlations were observed, demonstrating the validity of the Nano Sampler. PM?? and PM?.? concentrations during the measurement were 150.5 ± 96.0 ?g/m³ (mean ± standard variation) and 106.9 ± 71.6 ?g/m³, respectively. The PM?.?/PM?? ratio was 0.70 ± 0.10, indicating that PM?.? dominated PM??. The aerosol size distributions showed that three size bins of 0.5-1, 1-2.5 and 2.5-10 ?m contributed 21.8%, 23.3% and 26.0% to the total mass concentration (TMC), respectively. OM (organic matter) and SIA (secondary ionic aerosol, mainly SO?(2-), NO?(-) and NH?(+)) were major components of PM?.?. Secondary compounds (SIA and secondary organic carbon) accounted for half of TMC (about 49.8%) in PM?.?, and suggested that secondary aerosols significantly contributed to the serious particulate matter pollution observed in winter. Coal burning, biomass combustion, vehicle emissions and SIA were found to be the main sources of PM?.?. Mass concentrations of water-soluble ions and undetected materials, as well as their fractions in TMC, strikingly increased with deteriorating particle pollution conditions, while OM and EC (elemental carbon) exhibited different variations, with mass concentrations slightly increasing but fractions in TMC decreasing.
Related JoVE Video
Identification and characterization of long intergenic non-coding RNAs related to mouse liver development.
Mol. Genet. Genomics
PUBLISHED: 06-20-2014
Show Abstract
Hide Abstract
Long non-coding RNAs (lncRNAs) have been studied extensively over the last few years. Liver is an important organ that plays a crucial role in glucose metabolism and homeostasis; however, there are few reports of the identification and functional characterization of lncRNAs with important roles in liver development. Therefore, it is necessary to systematically identify lncRNAs that are involved in liver development. In this paper, we assembled the transcriptome using published RNA-seq data across three mouse liver developmental stages and identified 4,882 putative long intergenic non-coding RNAs (lincRNAs) expressed in at least one of the investigated stages. Combining these with Ensembl lincRNAs, we established a reference catalog of 6,602 transcribed lincRNAs in the mouse liver. We then analyzed all the lincRNAs in this reference catalog systematically and revealed that liver lincRNAs carry different genomic signatures from protein-coding genes, while the putative lincRNAs are generally comparable with known Ensembl lincRNAs. In addition, putative lincRNAs are functionally associated with essential biological processes, including RNA splicing, protein localization and fatty acid metabolic process, implying that they may play an important role in regulating liver development. The validation of selected lincRNAs that are specifically expressed in developing liver tissues further suggested the effectiveness of our approach. Our study shows that lincRNAs that are differentially expressed during three liver developmental stages could have important regulatory roles in liver development. The identified putative lincRNAs are a valuable resource for further functional studies.
Related JoVE Video
Relationship of PIK3CA mutation and pathway activity with antiproliferative response to aromatase inhibition.
Breast Cancer Res.
PUBLISHED: 06-17-2014
Show Abstract
Hide Abstract
PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit ?) somatic mutations are the most common genetic alteration in breast cancer (BC). Their prognostic value and that of the phosphatidylinositol 3-kinase (PI3K) pathway in BC remains only partly defined. The effect of PIK3CA mutations and alterations of the PI3K pathway on the antiproliferative response to aromatase inhibitor treatment was determined.
Related JoVE Video
Expression of ALDH1 and TGF?2 in benign and malignant breast tumors and their prognostic implications.
Int J Clin Exp Pathol
PUBLISHED: 06-15-2014
Show Abstract
Hide Abstract
The specific mechanism underlying the role of putative stem cell marker aldehyde dehydrogenase 1 (ALDH1) playing in development and progression of breast cancer is currently unclear. Transforming growth factor ? (TGF?) signaling pathway is reported to be activated in most cancers. Thus a study was initiated to explore possible differences and correlation of ALDH1 and TGF?2 expression in the most common malignant and benign tumors of the breast in Chinese women. Samples of 75 breast cancer tissues, 30 paracancerous normal tissues, and 39 fibroadenoma breast tissues were investigated for the expression of ALDH1 and TGF?2 using immunohistochemistry. The positive rates of ALDH1 and TGF?2 protein were 62.67% and 66.67%, respectively, in breast cancer tissues, which were significantly higher than that in normal fibroadenoma breast (P<0.05) and paracancerous tissues (P<0.01). ALDH1 and TGF?2 status were significantly associated with tumor histological grade and receptor status (P<0.05). Expression of ALDH1 was found to be positively correlative to TGF?2 in breast cancer (r = 0.33, P<0.01). Expression of both proteins remained significantly associated with reduced overall survival (OS) by univariate analysis (P<0.05). Multivariate Cox regression analysis showed that ALDH1 expression, tumor stage, and lymph node status are independent prognostic factors in invasive breast cancer patients. Thus ALDH1 and TGF?2 play important roles in the development of breast cancer. The ALDH1 phenotype is an independent predictor of poor prognosis, and TGF?2 signaling pathway activation might be involved in the pathological regulation of ALDH1 in breast cancer.
Related JoVE Video
Differences in the transcriptional response to fulvestrant and estrogen deprivation in ER-positive breast cancer.
Clin. Cancer Res.
PUBLISHED: 06-10-2014
Show Abstract
Hide Abstract
Endocrine therapies include aromatase inhibitors and the selective estrogen receptor (ER) downregulator fulvestrant. This study aimed to determine whether the reported efficacy of fulvestrant over anastrozole, and high- over low-dose fulvestrant, reflect distinct transcriptional responses.
Related JoVE Video
Is right ventricular mid-septal pacing superior to apical pacing in patients with high degree atrio-ventricular block and moderately depressed left ventricular function?
J Zhejiang Univ Sci B
PUBLISHED: 06-07-2014
Show Abstract
Hide Abstract
We are aimed to investigate whether right ventricular mid-septal pacing (RVMSP) is superior to conventional right ventricular apical pacing (RVAP) in improving clinical functional capacity and left ventricular ejection fraction (LVEF) for patients with high-degree atrio-ventricular block and moderately depressed left ventricle (LV) function.
Related JoVE Video
Engineering Halomonas TD01 for the low-cost production of polyhydroxyalkanoates.
Metab. Eng.
PUBLISHED: 06-02-2014
Show Abstract
Hide Abstract
The halophile Halomonas TD01 and its derivatives have been successfully developed as a low-cost platform for the unsterile and continuous production of chemicals. Therefore, to increase the genetic engineering stability of this platform, the DNA restriction/methylation system of Halomonas TD01 was partially inhibited. In addition, a stable and conjugative plasmid pSEVA341 with a high-copy number was constructed to contain a LacI(q)-Ptrc system for the inducible expression of multiple pathway genes. The Halomonas TD01 platform, was further engineered with its 2-methylcitrate synthase and three PHA depolymerases deleted within the chromosome, resulting in the production of the Halomonas TD08 strain. The overexpression of the threonine synthesis pathway and threonine dehydrogenase made the recombinant Halomonas TD08 able to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV consisting of 4-6mol% 3-hydroxyvalerate or 3HV, from various carbohydrates as the sole carbon source. The overexpression of the cell division inhibitor MinCD during the cell growth stationary phase in Halomonas TD08 elongated its shape to become at least 1.4-fold longer than its original size, resulting in enhanced PHB accumulation from 69wt% to 82wt% in the elongated cells, further promoting gravity-induced cell precipitations that simplify the downstream processing of the biomass. The resulted Halomonas strains contributed to further reducing the PHA production cost.
Related JoVE Video
Development of an enhanced chromosomal expression system based on porin synthesis operon for halophile Halomonas sp.
Appl. Microbiol. Biotechnol.
PUBLISHED: 06-02-2014
Show Abstract
Hide Abstract
Since halophile Halomonas spp. can grow contamination free in seawater under unsterile and continuous conditions, it holds great promise for industrial biotechnology to produce low-cost chemicals in an economic way. Yet, metabolic engineering methods are urgently needed for Halomonas spp. It is commonly known that chromosomal expression is more stable yet weaker than plasmid one is. To overcome this challenge, a novel chromosomal expression method was developed for halophile Halomonas TD01 and its derivatives based on a strongly expressed porin gene as a site for external gene integration. The gene of interest was inserted downstream the porin gene, forming an artificial operon porin-inserted gene. This chromosome expression system was proven functional by some examples: First, chromosomal expression of heterologous polyhydroxybutyrate (PHB) synthase gene phaC Re from Ralstonia eutropha completely restored the PHB accumulation level in endogenous phaC knockout mutant of Halomonas TD01. The integrated phaC Re was expressed at the highest level when inserted at the locus of porin compared with insertions in other chromosome locations. Second, an inducible expression system was constructed in phaC-deleted Halomonas TD01 by integrating the lac repressor gene (lacI) into the porin site in the host chromosome. The native porin promoter was inserted with the key 21 bp DNA of lac operator (lacO) sequence to become an inducible promoter encoded in a plasmid. This inducible system allowed on-off switch of gene expression in Halomonas TD strains. Thus, the stable and strong chromosomal expression method in Halomonas TD spp. was established.
Related JoVE Video
Modeling the temporal evolution of an aero-optical aberration with the minimum description length principle.
Opt Lett
PUBLISHED: 05-31-2014
Show Abstract
Hide Abstract
A method of building a dynamical model for temporal evolution of an aero-optical aberration is presented. Based on the proper orthogonal decomposition (POD) of the optical aberration, the minimum description length (MDL) principle is used to select a dynamical model for the POD coefficients. The MDL principle can balance the model error against model size so as to prevent the model from overfitting. This strategy is validated with the numerical simulation of the aero-optical aberration caused by the supersonic mixing layer, and the model obtained can accurately predict the time evolution of the POD coefficients in short time. The potential application of our method in extending the bandwidth of the adaptive optics system is also discussed.
Related JoVE Video
Identification of reference genes for tissue-specific gene expression in Panax notoginseng using quantitative real-time PCR.
Biotechnol. Lett.
PUBLISHED: 05-11-2014
Show Abstract
Hide Abstract
Validated internal controls are prerequisites to accurately normalize gene expression levels. Here, 14 candidate reference genes in Panax notoginseng were characterized. Primer specificity and amplification efficiency were evaluated for each gene. Candidates were subjected to transcript quantification in the root, fibrous root, rhizome, leaf, receptacle, pedicel, and fruit tissues. Expression stability (M value) and normalization factor variation (Vn/Vn+1) were determined by geNorm. 26S-2 and ACT-2 exhibited the highest expression stability among the tissues. Gene expression of dammarenediol synthase was accurately detected after normalization to 26S-2 and ACT-2 was performed. Results were consistent when each or both of 26S-2 and ACT-2 were applied as internal control. Hence, this study provides useful information to normalize gene expression accurately in the tissue-specific transcripts of P. notoginseng.
Related JoVE Video
4-Phenylbutyric acid increases GLUT4 gene expression through suppression of HDAC5 but not endoplasmic reticulum stress.
Cell. Physiol. Biochem.
PUBLISHED: 04-30-2014
Show Abstract
Hide Abstract
The chemical chaperone 4-phenylbutyric acid (4-PBA) has been shown to relieve endoplasmic reticulum (ER) stress. Therefore, it improves insulin sensitivity and promotes glucose metabolism in skeletal muscle. Glucose transporter type 4 (GLUT4), as a major glucose transporter protein, plays a central role in glucose metabolism. Until now, it has been unclear whether 4-PBA affects GLUT4 gene expression and thus, contributes to glucose metabolism.
Related JoVE Video
Ginsenoside Rh2 alleviates dextran sulfate sodium-induced colitis via augmenting TGF? signaling.
Mol. Biol. Rep.
PUBLISHED: 04-30-2014
Show Abstract
Hide Abstract
Ginsenoside Rh2 (GRh2) has been reported to have therapeutic effects on various diseases. However, whether it may also affect the recovery from ulcerative colitis remains unknown. Here we induced colitis in mice by dextran sulfate sodium (DSS) administration, and then treated the mice with GRh2. We found that GRh2-treated mice showed significant alleviation of the DSS-induced colitis. Moreover, significant increase in the activity of TGF? signaling was detected in the GRh2-treated colon that had received DSS. To investigate whether there is a causative link among GRh2 treatment, TGF? signaling augment and the cure of colitis, we gave the DSS-treated mice a combination of GRh2 and a specific TGF? receptor I inhibitor, SB431542. SB431542 significantly decreased the activation of TGF? signaling in the colon from the GRh2-administrated mice, and consequently attenuated the therapeutic effect of GRh2. Our data thus demonstrate that GRh2 may alleviate DSS-induced colitis via augmenting TGF? signaling.
Related JoVE Video
The mechanism of anti-osteoporosis effects of 3-hydroxybutyrate and derivatives under simulated microgravity.
Biomaterials
PUBLISHED: 04-24-2014
Show Abstract
Hide Abstract
Skeletons have significant bone loss (osteoporosis) under microgravity environment. This study showed that microbial polyhydroxyalkanoates (PHA) degradation product, and also ketone body 3-hydroxybutyrate acid (3HB) and its derivative 3-hydroxybutyrate methyl ester (3HBME) inhibit the development of osteoporosis in mice maintained under simulated microgravity, helping preserve bone microstructure and mechanical property. Mice orally administrated with 3HB or 3HBME recovered much more quickly from osteoporosis resulted from simulated microgravity compared with the controls without 3HB or 3HBME treatments due to less calcium loss to the sera. It was known that abnormal activation of osteoclasts induced by microgravity led to bone tissue absorption and thus osteoporosis. In this study, it was found that 3HB or 3HBME down-regulated the nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), which is the transcription factor of pre-osteoclast differentiation. When NFATc1 activation and downstream functions were inhibited, 3HB or 3HBME was able to strongly reduce pre-osteoclast differentiation. As a result, bone absorption was prevented. It was demonstrated that 100 mg/kg 3HB resulted in the most obvious effect on osteoporosis prevention. Based on these results, 3HB and 3HBME should be further developed as novel drug candidates against osteoporosis induced by microgravity.
Related JoVE Video
TRPML1: an ion channel in the lysosome.
Handb Exp Pharmacol
PUBLISHED: 04-24-2014
Show Abstract
Hide Abstract
The first member of the mammalian mucolipin TRP channel subfamily (TRPML1) is a cation-permeable channel that is predominantly localized on the membranes of late endosomes and lysosomes (LELs) in all mammalian cell types. In response to the regulatory changes of LEL-specific phosphoinositides or other cellular cues, TRPML1 may mediate the release of Ca(2+) and heavy metal Fe(2+)/Zn(2+)ions into the cytosol from the LEL lumen, which in turn may regulate membrane trafficking events (fission and fusion), signal transduction, and ionic homeostasis in LELs. Human mutations in TRPML1 result in type IV mucolipidosis (ML-IV), a childhood neurodegenerative lysosome storage disease. At the cellular level, loss-of-function mutations of mammalian TRPML1 or its C. elegans or Drosophila homolog gene results in lysosomal trafficking defects and lysosome storage. In this chapter, we summarize recent advances in our understandings of the cell biological and channel functions of TRPML1. Studies on TRPML1's channel properties and its regulation by cellular activities may provide clues for developing new therapeutic strategies to delay neurodegeneration in ML-IV and other lysosome-related pediatric diseases.
Related JoVE Video
Method for perfusion decellularization of porcine whole liver and kidney for use as a scaffold for clinical-scale bioengineering engrafts.
Xenotransplantation
PUBLISHED: 04-23-2014
Show Abstract
Hide Abstract
Whole-organ engineering provides a new alternative source of donor organs for xenotransplantation. Utilization of decellularized whole-organ scaffolds, which can be created by detergent perfusion, is a strategy for tissue engineering. In this article, our aim is to scale up the decellularization process to human-sized liver and kidney to generate a decellularized matrix with optimal and stable characteristics on a clinically relevant scale.
Related JoVE Video
Enhanced thermal and mechanical properties of PVA composites formed with filamentous nanocellulose fibrils.
Carbohydr Polym
PUBLISHED: 04-16-2014
Show Abstract
Hide Abstract
Long filamentous nanocellulose fibrils (NCFs) were prepared from chemical-thermomechanical pulps (CTMP) using ultrasonication. Their contribution to enhancements in thermal stability and mechanical properties of poly(vinyl alcohol) films were investigated. The unique chemical pretreatment and mechanical effects of CTMP loosen and unfold fibers during the pulping process, which enables further chemical purification and subsequent ultrasound treatment for formation of NCFs. The NCFs exhibited higher crystallinity (72.9%) compared with that of CTMP (61.5%), and had diameters ranging from 50 to 120 nm. A NCF content of 6 wt% was found to yield the best thermal stability, light transmittance, and mechanical properties in the PVA/NCF composites. The composites also exhibited a visible light transmittance of 73.7%, and the tensile strength and Young's modulus were significantly improved, with values 2.8 and 2.4 times larger, respectively, than that of neat PVA.
Related JoVE Video
Elucidation of Arctigenin Pharmacokinetics After Intravenous and Oral Administrations in Rats: Integration of In Vitro and In Vivo Findings via Semi-mechanistic Pharmacokinetic Modeling.
AAPS J
PUBLISHED: 04-04-2014
Show Abstract
Hide Abstract
Although arctigenin (AR) has attracted substantial research interests due to its promising and diverse therapeutic effects, studies regarding its biotransformation were limited. The current study aims to provide information regarding the pharmacokinetic properties of AR via various in vitro and in vivo experiments as well as semi-mechanistic pharmacokinetic modeling. Our in vitro rat microsome incubation studies revealed that glucuronidation was the main intestinal and liver metabolic pathway of AR, which occurred with V max, K m, and Clint of 47.5?±?3.4 nmol/min/mg, 204?±?22 ?M, and 233?±?9 ?l/min/mg with intestinal microsomes and 2.92?±?0.07 nmol/min/mg, 22.7?±?1.2 ?M, and 129?±?4 ?l/min/mg with liver microsomes, respectively. In addition, demethylation and hydrolysis of AR occurred with liver microsomes but not with intestinal microsomes. In vitro incubation of AR and its metabolites in intestinal content demonstrated that glucuronides of AR excreted in bile could be further hydrolyzed back to the parent compound, suggesting its potential enterohepatic circulation. Furthermore, rapid formation followed by fast elimination of arctigenic acid (AA) and arctigenin-4'-O-glucuronide (AG) was observed after both intravenous (IV) and oral administrations of AR in rats. Linear pharmacokinetics was observed at three different doses for AR, AA, and AG after IV administration of AR (0.48-2.4 mg/kg, r (2)?>?0.99). Finally, an integrated semi-mechanistic pharmacokinetic model using in vitro enzyme kinetic and in vivo pharmacokinetic parameters was successfully developed to describe plasma concentrations of AR, AA, and AG after both IV and oral administration of AR at all tested doses.
Related JoVE Video
Microgrooved poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) affects the phenotype of vascular smooth muscle cells through let-7a-involved regulation of actin dynamics.
Biotechnol. Lett.
PUBLISHED: 03-25-2014
Show Abstract
Hide Abstract
Cell-substrate interaction is important in tissue engineering. Vascular smooth muscle cells (VSMCs) cultured on the microgrooved surface of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) showed a distinctive polarized morphology and a high expression level of let-7a compared with the flat substrates. LIMK2, a crucial regulator of actin dynamics, was identified as a new target of let-7a. F-Actin content on flat substrates was significantly higher than that on microgrooved ones. Either overexpression of let-7a on flat substrates or inhibited expression on microgrooved substrates can rescue the difference. In accord with actin dynamics, the expressions of contractile smooth muscle markers, such as SM22 and SMA, decreased in VSMCs cultured on microgrooved substrates compared to those on flat ones, though PHBHHx can induce the synthetic-to-contractile phenotype shift. These results indicate that microgrooved PHBHHx could enhance actin dynamics of VSMCs through let-7a-involved regulation and trigger a synthetic shift.
Related JoVE Video
Pharmacokinetics of liver-targeted docetaxel liposomes modified with 6-O-acyl-D-galactose esters in rabbits.
Biomed Rep
PUBLISHED: 03-19-2014
Show Abstract
Hide Abstract
The purpose of the present study was to investigate the pharmacokinetics of docetaxel liposomes modified with 6-O-acyl-D-galactose esters (Gal-DOC-L) in rabbits. A simple, rapid and sensitive high-performance liquid chromatography (HPLC) method was developed for the determination of docetaxel. Gal-DOC-L was intravenously administered to rabbits with norethisterone as the internal standard and the blood samples were collected from ear marginal veins at 0.083, 0.25, 0.5, l, 2, 4, 6, 8, 12, 16 and 24 h after treatment. The plasma concentration of docetaxel was determined by HPLC and the pharmacokinetic parameters were calculated. Docetaxel injection (DOC-I) was studied simultaneously. The results showed that the area under the curve(0-?), t1/2? and t1/2? of Gal-DOC-L was significantly higher, while the total body clearance was lower than that of DOC-I. The results indicated that Gal-DOC-L was able to maintain a relatively high blood concentration in vivo and prolong the treatment time.
Related JoVE Video
Freestanding Aligned Carbon Nanotube Array Grown on a Large-Area Single-Layered Graphene Sheet for Efficient Dye-Sensitized Solar Cell.
Small
PUBLISHED: 03-14-2014
Show Abstract
Hide Abstract
A novel carbon nanomaterial with aligned carbon nanotubes (CNTs) chemically bonded to a single-layered, large area graphene sheet is designed and fabricated, showing remarkable electronic and electrocatalytic properties. When the carbon nanomaterial is used as a counter electrode, the resulting dye-sensitized solar cell exhibits ?11% enhancement of energy conversion efficiency than aligned CNT array.
Related JoVE Video
Effect of aromatase inhibition on functional gene modules in estrogen receptor-positive breast cancer and their relationship with antiproliferative response.
Clin. Cancer Res.
PUBLISHED: 03-14-2014
Show Abstract
Hide Abstract
To investigate potential associations between gene modules representing key biologic processes and response to aromatase inhibitors (AI) in estrogen receptor-positive (ER(+)) breast cancer. Patients and Methods: Paired gene expression and Ki67 protein expression were available from 69 postmenopausal women with ER(+) early breast cancer, at baseline and 2 weeks post-anastrozole treatment, in the presurgical setting. Functional gene modules (n = 26) were retrieved from published studies and their module scores were computed before and after elimination of proliferation-associated genes (PAG). Ki67 and module scores were assessed at baseline and 2 weeks post-anastrozole. Unsupervised clustering was used to assess associations between modules and Ki67.
Related JoVE Video
The intracellular Ca(2+) channel MCOLN1 is required for sarcolemma repair to prevent muscular dystrophy.
Nat. Med.
PUBLISHED: 03-05-2014
Show Abstract
Hide Abstract
The integrity of the plasma membrane is maintained through an active repair process, especially in skeletal and cardiac muscle cells, in which contraction-induced mechanical damage frequently occurs in vivo. Muscular dystrophies (MDs) are a group of muscle diseases characterized by skeletal muscle wasting and weakness. An important cause of these group of diseases is defective repair of sarcolemmal injuries, which normally requires Ca(2+) sensor proteins and Ca(2+)-dependent delivery of intracellular vesicles to the sites of injury. MCOLN1 (also known as TRPML1, ML1) is an endosomal and lysosomal Ca(2+) channel whose human mutations cause mucolipidosis IV (ML4), a neurodegenerative disease with motor disabilities. Here we report that ML1-null mice develop a primary, early-onset MD independent of neural degeneration. Although the dystrophin-glycoprotein complex and the known membrane repair proteins are expressed normally, membrane resealing was defective in ML1-null muscle fibers and also upon acute and pharmacological inhibition of ML1 channel activity or vesicular Ca(2+) release. Injury facilitated the trafficking and exocytosis of vesicles by upmodulating ML1 channel activity. In the dystrophic mdx mouse model, overexpression of ML1 decreased muscle pathology. Collectively, our data have identified an intracellular Ca(2+) channel that regulates membrane repair in skeletal muscle via Ca(2+)-dependent vesicle exocytosis.
Related JoVE Video
An in vivo functional screen identifies ST6GalNAc2 sialyltransferase as a breast cancer metastasis suppressor.
Cancer Discov
PUBLISHED: 02-11-2014
Show Abstract
Hide Abstract
To interrogate the complex mechanisms involved in the later stages of cancer metastasis, we designed a functional in vivo RNA interference (RNAi) screen combined with next-generation sequencing. Using this approach, we identified the sialyltransferase ST6GalNAc2 as a novel breast cancer metastasis suppressor. Mechanistically, ST6GalNAc2 silencing alters the profile of O-glycans on the tumor cell surface, facilitating binding of the soluble lectin galectin-3. This then enhances tumor cell retention and emboli formation at metastatic sites leading to increased metastatic burden, events that can be completely blocked by galectin-3 inhibition. Critically, elevated ST6GALNAC2, but not galectin-3, expression in estrogen receptor-negative breast cancers significantly correlates with reduced frequency of metastatic events and improved survival. These data demonstrate that the prometastatic role of galectin-3 is regulated by its ability to bind to the tumor cell surface and highlight the potential of monitoring ST6GalNAc2 expression to stratify patients with breast cancer for treatment with galectin-3 inhibitors.
Related JoVE Video
Vaccination with DKK1-derived peptides promotes bone formation and bone mass in an aged mouse osteoporosis model.
Calcif. Tissue Int.
PUBLISHED: 01-24-2014
Show Abstract
Hide Abstract
The investigation of agents for the treatment of osteoporosis has been a long-standing effort. The Wnt pathway plays an important role in bone formation and regeneration, and expression of Wnt pathway inhibitors, Dickkopf-1 (DKK1), appears to be associated with changes in bone mass. Inactivation of DKK1 leads to substantially increased bone mass in genetically manipulated animals. DKK1-derived peptides (DDPs) were added to BMP2-stimulated MC3T3-E1 preosteoblastic cells in vitro to evaluate inhibitory activity of DDPs in MC3T3-E1 cell differentiation. Study was extended in vivo on old female mice to show whether or not inhibition of endogenous DKK1 biological activity using DDPs vaccination approach leads to increase of bone formation, bone density, and improvement of bone microstructure. We reported that synthetic DDPs were able to reduce alkaline phosphatase activity, prevent mineralization and inhibit the differentiation of MC3T3-E1 cells in vitro. Furthermore, vaccination with these DDPs in aged female mice 4 times for a total period of 22 weeks promoted bone mass and bone microstructure. 3D microCT and histomorphometric analysis showed that there were significant increase in bone mineral densities, improvement of bone microstructure and promotion of bone formation in the vaccinated mice, especially in the mice vaccinated with DDP-A and DDP-C. Histological and scanning electron microscopy image analysis also indicated that vaccination increased trabecular bone mass and significantly decreased fragmentation of bone fibers. Taken together, these preclinical results suggest that vaccination with DDPs represents a promising new therapeutic approach for the treatment of bone-related disorders, such as osteoporosis.
Related JoVE Video
Mixed logit model-based driver injury severity investigations in single- and multi-vehicle crashes on rural two-lane highways.
Accid Anal Prev
PUBLISHED: 01-21-2014
Show Abstract
Hide Abstract
Crashes occurring on rural two-lane highways are more likely to result in severe driver incapacitating injuries and fatalities. In this study, mixed logit models are developed to analyze driver injury severities in single-vehicle (SV) and multi-vehicle (MV) crashes on rural two-lane highways in New Mexico from 2010 to 2011. A series of significant contributing factors in terms of driver behavior, weather conditions, environmental characteristics, roadway geometric features and traffic compositions, are identified and their impacts on injury severities are quantified for these two types of crashes, respectively. Elasticity analyses and transferability tests were conducted to better understand the models' specification and generality. The research findings indicate that there are significant differences in causal attributes determining driver injury severities between SV and MV crashes. For example, more severe driver injuries and fatalities can be observed in MV crashes when motorcycles or trucks are involved. Dark lighting conditions and dusty weather conditions are found to significantly increase MV crash injury severities. However, SV crashes demonstrate different characteristics influencing driver injury severities. For example, the probability of having severe injury outcomes is higher when vans are identified in SV crashes. Drivers' overtaking actions will significantly increase SV crash injury severities. Although some common attributes, such as alcohol impaired driving, are significant in both SV and MV crash severity models, their effects on different injury outcomes vary substantially. This study provides a better understanding of similarities and differences in significant contributing factors and their impacts on driver injury severities between SV and MV crashes on rural two-lane highways. It is also helpful to develop cost-effective solutions or appropriate injury prevention strategies for rural SV and MV crashes.
Related JoVE Video
Extensive intestinal first-pass metabolism of arctigenin: evidenced by simultaneous monitoring of both parent drug and its major metabolites.
J Pharm Biomed Anal
PUBLISHED: 01-18-2014
Show Abstract
Hide Abstract
The current study aims to investigate intestinal absorption and metabolism of arctigenin (AR) through simultaneous monitoring of AR and its major metabolites in rat plasma. An UPLC/MS/MS assay was developed with chromatographic separation of all analytes achieved by a C18 Column (3.9mm×150mm, 3.5?m) and a gradient elution with acetonitrile and 0.1% formic acid within 9min. Sample extraction with acetonitrile was optimized to achieve satisfactory recovery for both AR and its major metabolites. The lower limit of quantification (LLOQ) for all analytes was 25ng/ml. The intra-day and inter-day precision and accuracy of each analyte at LLOQ and three quality control (QC) concentrations (low, middle and high) in rat plasma was within 15.0% RSD and 15.0% bias. The extraction recoveries were within the range of 83.8-94.0% for all analytes. The developed and validated assay was then applied to the absorption study of AR in both Caco-2 cell monolayer model and in situ single-pass rat intestinal perfusion model. High absorption permeability of AR was demonstrated in both models with Papp of (1.76±0.48)×10(-5) (A?B) (Caco-2) and Pblood of (8.6±3.0)×10(-6)cm/s (intestinal perfusion). Extensive first-pass metabolism of AR to arctigenic acid (AA) and arctigenin-4'-O-glucuronide (AG) was identified in rat intestinal perfusion study with Cummins's extraction ratios of 0.458±0.012 and 0.085±0.013, respectively. The current assay method demonstrated to be a practical tool for pharmacokinetics investigation of AR with complicated metabolism pathways and multiple metabolites.
Related JoVE Video
Determination of five pyrethroids in tea drinks by dispersive solid phase extraction with polyaniline-coated magnetic particles.
Talanta
PUBLISHED: 01-10-2014
Show Abstract
Hide Abstract
The polyaniline-coated magnetic particles with bowl-shaped morphology (Fe3O4/C/PANI microbowls) were successfully prepared and characterized by scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometry. The prepared microbowls were used as the magnetic adsorbent in dispersive solid phase extraction of five pyrethroids, including cyhalothrin, beta-cypermethrin, esfenvalerate, permethrin and bifenthrin in plain tea drinks. The effects of experiment factors, including amount of Fe3O4/C/PANI microbowls, pH value, ultrasound extraction time and desorption conditions, were investigated. The extraction recoveries obtained with 8 mg of magnetic microbowls were satisfactory, and the microbowls can be reused after easy washing. Thus, a simple, selective and effective method for the determination of the pyrethroids was established successfully. The results showed that the method had good linearity (r=0.9992-0.9998), and the limits of detections (LODs) were from 0.025 to 0.032 ng mL(-1). The intra-day and inter-day relative standard deviations (RSDs) were in the range of 2.4-6.1% and 3.5-8.8%, respectively. Recoveries obtained by analyzing the real tea drinks were in the range of 72.1-118.4%.
Related JoVE Video
Prognostic role of SPARC expression in gastric cancer: a meta-analysis.
Arch Med Sci
PUBLISHED: 01-05-2014
Show Abstract
Hide Abstract
Secreted protein acidic and rich in cysteine (SPARC) is involved in regulating cell adhesion, proliferation, migration, and tissue remodeling. We performed a meta-analysis to evaluate the association between SPARC expression and the clinicopathologic features and outcomes of gastric cancer patients.
Related JoVE Video
Discerning Fragmentation Dynamics of Tropical Forest and Wetland during Reforestation, Urban Sprawl, and Policy Shifts.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Despite the overall trend of worldwide deforestation over recent decades, reforestation has also been found and is expected in developing countries undergoing fast urbanization and agriculture abandonment. The consequences of reforestation on landscape patterns are seldom addressed in the literature, despite their importance in evaluating biodiversity and ecosystem functions. By analyzing long-term land cover changes in Puerto Rico, a rapidly reforested (6 to 42% during 1940-2000) and urbanized tropical island, we detected significantly different patterns of fragmentation and underlying mechanisms among forests, urban areas, and wetlands. Forest fragmentation is often associated with deforestation. However, we also found significant fragmentation during reforestation. Urban sprawl and suburb development have a dominant impact on forest fragmentation. Reforestation mostly occurs along forest edges, while significant deforestation occurs in forest interiors. The deforestation process has a much stronger impact on forest fragmentation than the reforestation process due to their different spatial configurations. In contrast, despite the strong interference of coastal urbanization, wetland aggregation has occurred due to the effective implementation of laws/regulations for wetland protection. The peak forest fragmentation shifted toward rural areas, indicating progressively more fragmentation in forest interiors. This shift is synchronous with the accelerated urban sprawl as indicated by the accelerated shift of the peak fragmentation index of urban cover toward rural areas, i.e., 1.37% yr-1 in 1977-1991 versus 2.17% yr-1 in 1991-2000. Based on the expected global urbanization and the regional forest transition from deforested to reforested, the fragmented forests and aggregated wetlands in this study highlight possible forest fragmentation processes during reforestation in an assessment of biodiversity and functions and suggest effective laws/regulations in land planning to reduce future fragmentation.
Related JoVE Video
MicroRNA-137 Upregulation Increases Bladder Cancer Cell Proliferation and Invasion by Targeting PAQR3.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
There is increasing evidence suggesting that dysregulation of some microRNAs (miRNAs) may contribute to tumor progression and metastasis and have been proposed to be key regulators of diverse biological processes such as transcriptional regulation, cell growth and tumorigenesis. Previous studies have shown that miR-137 is dysregulated in some malignancies, but its role in bladder cancer is still unknown. In our study, we find that miR-137 is up-regulated in human bladder cancer tissues and cell lines. Moreover, the higher level of miR-137 was associated with pM or pTNM stage in clinical bladder cancer patients. Enforced expression of miR-137 in bladder cancer cells significantly enhanced their proliferation, migration and invasion. Bioinformatics analysis identified the tumor suppressor gene PAQR3 as a potential miR-137 target gene. Further studies indicated that miR-137 suppressed the expression of PAQR3 by binding to its 3'-untranslated region. Silencing of PAQR3 by small interfering RNAs phenocopied the effects of miR-137 overexpression, whereas restoration of PAQR3 in bladder cancer cells bladder cancer cells overexpressing miR-137, partially reversed the suppressive effects of miR-137. These findings indicate that miR-137 could be a potential oncogene in bladder cancer.
Related JoVE Video
Scorpion Venom Heat-Resistant Peptide (SVHRP) Enhances Neurogenesis and Neurite Outgrowth of Immature Neurons in Adult Mice by Up-Regulating Brain-Derived Neurotrophic Factor (BDNF).
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Although scorpions and their venom have been used in Traditional Chinese Medicine (TCM) to treat chronic neurological disorders, the underlying mechanisms of these treatments remain unknown. We applied SVHRP in vitro and in vivo to understand its effects on the neurogenesis and maturation of adult immature neurons and explore associated molecular mechanisms. SVHRP administration increased the number of 5-bromo-2'-dexoxyuridine (BrdU)-positive cells, BrdU- positive/neuron-specific nuclear protein (NeuN)-positive neurons, and polysialylated-neural cell adhesion molecule (PSA-NCAM)-positive immature neurons in the subventricular zone (SVZ) and subgranular zone (SGZ) of hippocampus. Furthermore immature neurons incubated with SVHRP-pretreated astrocyte-conditioned medium exhibited significantly increased neurite length compared with those incubated with normal astrocyte-conditioned medium. This neurotrophic effect was further confirmed in vivo by detecting an increased average single area and whole area of immature neurons in the SGZ, SVZ and olfactory bulb (OB) in the adult mouse brain. In contrast to normal astrocyte-conditioned medium, higher concentrations of brain-derived neurotrophic factor (BDNF) but not nerve growth factor (NGF) or glial cell line-derived neurotrophic factor (GDNF) was detected in the conditioned medium of SVHRP-pretreated astrocytes, and blocking BDNF using anti-BDNF antibodies eliminated these SVHRP-dependent neurotrophic effects. In SVHRP treated mouse brain, more glial fibrillary acidic protein (GFAP)-positive cells were detected. Furthermore, immunohistochemistry revealed increased numbers of GFAP/BDNF double-positive cells, which agrees with the observed changes in the culture system. This paper describes novel effects of scorpion venom-originated peptide on the stem cells and suggests the potential therapeutic values of SVHRP.
Related JoVE Video
NMR characterization of an oligonucleotide model of the miR-21 pre-element.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
We have used NMR spectroscopy to characterize an oligonucleotide stem loop structure based on the pre-element of an oncogenic microRNA, miR-21. This predicted stem-loop structure is cleaved from the precursor of miR-21 (pre-miR-21) by the nuclease Dicer. It is also a critical feature recognized by the protein complex that converts the primary transcript (pri-miR-21) into the pre-miRNA. The secondary structure of the native sequence is poorly defined by NMR due to rapid exchange of imino protons with solvent; however, replacement of two adjacent putative G•U base pairs with G•C base pairs retains the conformation of the hairpin observed by chemical probing and stabilizes it sufficiently to observe most of the imino proton resonances of the molecule. The observed resonances are consistent with the predicted secondary structure. In addition, a peak due to a loop uridine suggests an interaction between it and a bulged uridine in the stem. Assignment of non-exchangeable proton resonances and characterization of NOEs and coupling constants allows inference of the following features of the structure: extrahelicity of a bulged adenosine, deviation from A-form geometry in a base-paired stem, and consecutive stacking of the adenosines in the 5' side of the loop, the guanosine of the closing base pair, and a cross-strand adenosine. Modeling of the structure by restrained molecular dynamics suggests a basis for the interaction between the loop uridine, the bulged uridine in the stem, and an A•U base pair in the stem.
Related JoVE Video
Biological role of Trichoderma harzianum-derived platelet-activating factor acetylhydrolase (PAF-AH) on stress response and antagonism.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
We investigated the properties of platelet-activating factor acetylhydrolase (PAF-AH) derived from Trichoderma harzianum. The enzyme, comprised of 572 amino acids, shares high homology with PAF-AH proteins from T. koningii and other microbial species. The optimum enzymatic activity of PAF-AH occurred at pH 6 in the absence of Ca2+ and it localized in the cytoplasm, and we observed the upregulation of PAF-AH expression in response to carbon starvation and strong heat shock. Furthermore, PAF-AH knockout transformant growth occurred more slowly than wild type cells and over-expression strains grown in SM medium at 37°C and 42°C. In addition, PAF-AH expression significantly increased under a series of maize root induction assay. Eicosanoic acid and ergosterol levels decreased in the PAF-AH knockouts compared to wild type cells, as revealed by GC/MS analysis. We also determined stress responses mediated by PAF-AH were related to proteins HEX1, Cu/Zn superoxide dismutase, and cytochrome c. Finally, PAF-AH exhibited antagonistic activity against Rhizoctonia solani in plate confrontation assays. Our results indicate PAF-AH may play an important role in T. harzianum stress response and antagonism under diverse environmental conditions.
Related JoVE Video
Experimental study on effect of simulated microgravity on structural chromosome instability of human peripheral blood lymphocytes.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Experimental study was made by keeping human peripheral blood lymphocytes under simulated microgravity in a Rotary Cell Culture System bioreactor to investigate the changes that occur in the number of chromosomes, the expression rate of chromosome fragile site, and the expressions of DNA replication- and repair-related genes. Experimental results indicate simulated microgravity has no effect on the numerical chromosome instability of human peripheral blood lymphocytes, but it enhances the structural chromosome instability of human peripheral blood lymphocytes through the inhibition of DNA replication and the reduction of DNA repair. So, the mechanism of chromosome fragile site induced by simulated microgravity can be explained using the changes that occur in the chromosome structure of human peripheral blood lymphocytes, the DNA replication and repair under the effect of simulated microgravity.
Related JoVE Video
Kidney Diseases Enhance Expression of Tetraspanin-8: A Possible Protective Effect against Tubular Injury.
Nephron Extra
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
TSPAN8 encoding tetraspanin-8 was identified as a candidate gene for immunoglobulin A nephropathy (IgAN) by a genome-wide association study using microsatellites in the Japanese population. Tetraspanin-8 is a cell surface protein that contributes to the migration and invasion of epithelial cells.
Related JoVE Video
Downregulation of the transcription factor, FoxD3, is associated with lymph node metastases in invasive ductal carcinomas of the breast.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
FoxD3 is a transcription factor of the forkhead gene family. We investigated its expression in invasive ductal carcinomas (IDC) of the breast and its association with metastasis. The expression of FoxD3, human epidermal growth factor receptor-2 (HER-2), estrogen receptor (ER), progesterone receptor (PR) and Ki67 was examined by immunohistochemistry in samples from 121 patients with IDC. Non-tumorous breast adenosis tissues served as controls. HER2 expression was confirmed by fluorescence in situ hybridization (FISH). The expression levels of FoxD3 in IDC tissues and the breast cancer cell lines MCF-7 and MDA-MB-231 were additionally measured by western blotting. A greater percentage of total IDC patients and patients with lymph node metastases showed reduced FoxD3 expression compared to adenosis controls (p<0.05). Overall, FoxD3 was associated with metastatic status of IDC but not with age, pathological or clinical staging, or status of HER-2, ER, or PR. In particular, FoxD3 protein expression was down-regulated in the tumor epithelia of IDC samples from patients with metastases. Furthermore, FoxD3 protein expression was decreased in the metastatic MDA-MB-231 breast cancer cell line relative to the non-metastatic cell line, MCF-7. A greater number of patients with invasive, triple-negative breast cancer were also negative for FoxD3 expression than in other, non-triple-negative tumor types. These results suggest an inverse relationship between FoxD3 expression and tumor metastasis and warrants further investigation.
Related JoVE Video
Care-seeking and quality of care for outpatient sick children in rural Hebei, China: a cross-sectional study.
Croat. Med. J.
PUBLISHED: 12-31-2013
Show Abstract
Hide Abstract
Aim. To assess the quality of outpatient pediatric care provided by township and village doctors, prevalence of common childhood diseases, care-seeking behavior, and coverage of key interventions in Zhao County in China. Methods. We conducted two cross-sectional surveys: 1) maternal, newborn, and child health household survey including1601 caregivers of children younger than two years; 2) health facility survey on case management of 348 sick children younger than five years by local health workers and assessment of the availability of drugs and supplies in health facility. Results. Our household survey showed that the prevalence of fever, cough, and diarrhea was 16.8%, 9.2%, and 15.6% respectively. Caregivers of children with fever, cough, and diarrhea sought care primarily in village clinics and township hospitals. Only 41.2% of children with suspected pneumonia received antibiotics, and very few children with diarrhea received oral rehydration solutions (1.2%) and zinc (4.4%). Our facility survey indicated that very few sick children were fully assessed, and only 43.8% were correctly classified by health workers when compared with the gold standard. Use of antibiotics for sick children was high and not according to guidelines. Conclusion. We showed poor quality of services for outpatient sick children in Zhao County. Since Integrated Management of Childhood Illness strategy has shown positive effects on child health in some areas of China, it is advisable to implement it in other areas as well.
Related JoVE Video
[Protective effect of baicalin against LPS-induced intestinal injury].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 12-31-2013
Show Abstract
Hide Abstract
To investigate the protective effect of baicalin on the intestinal mucosal injury caused by endotoxin-lipopolysaccharide (LPS) and the anti-oxidative injury in colonic and ileal mucosa of rats with septicopyemia.
Related JoVE Video
mHealth Series: Factors influencing sample size calculations for mHealth-based studies - A mixed methods study in rural China.
J Glob Health
PUBLISHED: 12-24-2013
Show Abstract
Hide Abstract
An important issue for mHealth evaluation is the lack of information for sample size calculations.
Related JoVE Video
simple hit counter

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.

How does it work?

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.