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Find video protocols related to scientific articles indexed in Pubmed.
The cost-benefit of using soft silicone multilayered foam dressings to prevent sacral and heel pressure ulcers in trauma and critically ill patients: a within-trial analysis of the Border Trial.
Int Wound J
PUBLISHED: 05-13-2015
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Little is known about the cost-benefit of soft silicone foam dressings in pressure ulcer (PU) prevention among critically ill patients in the emergency department (ED) and intensive care unit (ICU). A randomised controlled trial to assess the efficacy of soft silicone foam dressings in preventing sacral and heel PUs was undertaken among 440 critically ill patients in an acute care hospital. Participants were randomly allocated either to an intervention group with prophylactic dressings applied to the sacrum and heels in the ED and changed every 3 days in the ICU or to a control group with standard PU prevention care provided during their ED and ICU stay. The results showed a significant reduction of PU incidence rates in the intervention group (P = 0·001). The intervention cost was estimated to be AU$36·61 per person based on an intention-to-treat analysis, but this was offset by lower downstream costs associated with PU treatment (AU$1103·52). Therefore, the average net cost of the intervention was lower than that of the control (AU$70·82 versus AU$144·56). We conclude that the use of soft silicone multilayered foam dressings to prevent sacral and heel PUs among critically ill patients results in cost savings in the acute care hospital.
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A simple and convenient approach for preparing core-shell-like silica@nickel species nanoparticles: highly efficient and stable catalyst for the dehydrogenation of 1,2-cyclohexanediol to catechol.
Dalton Trans
PUBLISHED: 11-20-2014
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A simple and convenient approach denoted as gel-deposition-precipitation (G-D-P) for the preparation of core-shell-like silica@nickel species nanoparticles was studied systematically. Core-shell-like silica@nickel species nanoparticles consisted of a Si-rich core and a Ni-rich shell. The G-D-P process included two steps: one was the deposition-precipitation of nickel over the gelled colloidal silica particle, generating core-shell-like silica@nickel species nanoparticles, and the other was the aging period. It was found that the nickel phyllosilicate layer was formed mainly during the aging period and served as the protective cover to resist against aggregation of the nanoparticles, which could be utilized for regulating the dispersion of nickel over the silica@nickel species nanoparticles. In the present paper, the silica@nickel species nanoparticles were used as the catalysts for preparing catechol via dehydrogenation of 1,2-cyclohexanediol. Their catalytic activity and long-term stability were compared to those of a catalyst prepared by a conventional deposition-precipitation (D-P) approach. The higher activity and better stability of the title reaction over the silica@nickel species nanoparticles catalyst prepared by G-D-P than those over the catalyst prepared by D-P could be due to the higher dispersion of metallic nickel stabilized by the layers of nickel phyllosilicates. Moreover, it was found that the dehydrogenation of 1,2-cyclohexanediol to catechol was a structurally sensitive reaction.
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Antioxidative Effects of Schidandrin B and Green Tea Polyphenols Against Mercuric Chloride-Induced Hepatotoxicity in rats.
J. Environ. Pathol. Toxicol. Oncol.
PUBLISHED: 11-19-2014
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In the present study, we investigated the hepatoprotective effects of schisandrin B (Sch B) and green tea polyphenols (GrTP), two natural antioxidants, against Hg hepatotoxicity. Fifty-six rats were randomly divided into four groups of fourteen animals in each group: control group, Hg-treated group, Sch B pretreated group, and GrTP pretreated group. HgCl2 injection increased Hg accumulation, pathological and ultrastructural injury, lactate dehydrogenase (LDH) level, alanine transaminase (ALT) level, apoptosis, reactive oxygen species (ROS) level, glutathione (GSH) level, and malondialdehyde (MDA) level. HgCl2 injection decreased glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities. Sch B and GrTP protected against Hg-induced dysfunction and liver injury by enhancing the antioxidant defense system. Our results indicate that Sch B and GrTP exert antioxidative effects against Hg-induced hepatotoxicity in rats.
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IDH2 mutation induced histone and DNA hypermethylation is progressively reversed by small molecule inhibition.
Blood
PUBLISHED: 11-16-2014
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Mutations of IDH1 and IDH2, which produce the oncometabolite 2-hydroxyglutarate (2HG), have been identified in several tumors including acute myeloid leukemia (AML). Recent studies have shown that expression of the IDH mutant enzymes results in high levels of 2HG and a block in cellular differentiation that can be reversed with IDH-mutant specific small molecule inhibitors. To further understand the role of IDH mutations in cancer, we conducted mechanistic studies in the TF-1 IDH2 R140Q erythroleukemia model system and found that IDH2 mutant expression caused both histone and genomic DNA methylation changes that can be reversed when IDH2 mutant activity is inhibited. Specifically, histone hypermethylation is rapidly reversed within days whereas reversal of DNA hypermethylation proceeds in a progressive manner over the course of weeks. We identified several gene signatures implicated in tumorigenesis of leukemia and lymphoma, indicating a selective modulation of relevant cancer genes by IDH mutations. As methylation of DNA and histones is closely linked to mRNA expression and differentiation, these results indicate that IDH2 mutant inhibition may function as a cancer therapy via histone and DNA demethylation at genes involved in differentiation and tumorigenesis.
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Validation of the Nonmotor Symptoms Questionnaire for Parkinson's disease: Results from a Chinese Pilot Study.
Int. J. Neurosci.
PUBLISHED: 11-12-2014
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ABSTRACT We performed a cross-sectional study of 82 Chinese patients with Parkinson's disease (PD) enrolled during an 18-month period. We used a clinical interview to evaluate a Chinese version of the nonmotor symptoms questionnaire (NMSQuest) as an instrument for measuring the nonmotor symptoms (NMS) in Chinese patients with PD. The patients' cognitive deficit, depression/sleep, disease severity, and motor status were assessed based on the mini-mental state examination (MMSE), the Hamilton depression scale (HAMD)/Parkinson's disease sleep scale (PDSS), the modified Hoehn and Yahr staging scale (H&Y), and the unified Parkinson's disease rating scale part III (UPDRS III), respectively. Thirty items distributed in nine different domains of the NMSQuest were evaluated, and the association between the NMSQuest and MMSE, H&Y, UPDRS, HAMD, and PDSS was identified. Significant correlations were observed between the NMSQuest and disease duration (rs = 0.272, P = 0.013), UPDRS total score (rs = 0.444, P < 0.001), UPDRS II (rs = 0.415, P < 0.001), and UPDRS III (rs = 0.228, P = 0.039). Furthermore, the sleep disorder and mood (depression/anxiety) domain of the NMSQuest were significantly correlated with the PDSS (rs = -0.471, P < 0.001) and HAMD (rs = 0.687, P < 0.001), respectively. Our results indicate that the Chinese version of the NMSQuest, a useful screening tool, can be considered as a comprehensive, practical measure for NMS evaluation in Chinese PD patients. The NMSQuest highlights the prevalence of the wide range of NMS and indicated good responsiveness and interpretability. We strongly recommend routine use of the simplified Chinese version of NMSQuest in this country.
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Water-Soluble Colorimetric and Ratiometric Fluorescent Probe for Selective Imaging of Palladium Species in Living Cells.
Inorg Chem
PUBLISHED: 11-11-2014
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A novel water-soluble colorimetric and ratiometric fluorescent probe was synthesized and applied to imaging palladium species under physiological conditions in phosphate buffered saline (PBS) containing less than 1% organic cosolvent without adding any additional reagents. Based on palladium triggered terminal propargyl ethers cleavage reaction, the probe exhibited a high selectivity and sensitivity for palladium species of all the typical oxidation states (0, +2, +4), with a low detection limit (25 nM, 2.7 ?g/L) and an obvious color change. Furthermore, the probe was successfully used for ratiometric fluorescence imaging of palladium in living cells.
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In Vitro Immunological Effects of Blocking CCR5 on T Cells.
Inflammation
PUBLISHED: 11-09-2014
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Blockade of CC chemokine receptor 5 (CCR5) by maraviroc may induce immunological changes independent of its antiviral effects and may have immunoregulation properties. This study was designed to determine the effects of blocking CCR5 on human activated T cells in vitro and investigate the potential immunological mechanisms. Human CD3+ T cells were purified from peripheral blood mononuclear cells and then activated by cytokines. We tested the surface expressions and relative messenger RNA (mRNA) levels of CCR2, CCR5, CCR6, CCR7, and CXCR3, chemotaxis toward their cognate ligands, internalization of chemokine receptors, and production of cytokines. In conclusion, blocking CCR5 by maraviroc not only can block CCR5 and CCR2 internalization processes induced by CCL5 and CCL2, but also inhibit T cell chemotactic activities toward their cognate ligands, respectively. Moreover, blocking CCR5 with maraviroc at high doses tends to decrease the production of TNF-? and IFN-?. In addition, there might be a form of cross talk between CCR5 and CCR2, and this may offer a novel immunological effect for blockade of CCR5.
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Subtemporal-anterior transtentoral approach to middle cranial fossa microsurgical anatomy.
J Craniofac Surg
PUBLISHED: 11-08-2014
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This study aimed to describe the topography of inferior and external dura mater of the middle cranial fossa through subtemporal-anterior transpetrosal approach and discuss the feasibility of improving the approach. Eight formalin-fixed adult cadaveric heads were studied, with the bones milled away in the lateral triangle region of the petrous bone, Kawase rhombus region, and inner triangle region of the petrous apex. The distances between the targets in these regions, as well as the angles after the dissection of zygomatic arch, were measured, and then the exposed petroclival and retrochiasmatic areas were observed under the microscope. There were significant variations in the distances between targets in the 3 milled regions among the specimens. After the dissection of zygomatic arch, the surgical view got an average increase of 12 degrees. The subtemporal anterior transpetrosal approach, as an improved subtemporal approach, can expose the lesions optimally, causing no injury to the hearing and reducing injuries to temporal lobe. On the other hand, the lateral bone of the petrous parts of the temporal bone is removed so as to improve the view to the retrochiasmatic area and expand the operative field.
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Inappropriate left ventricular mass and poor outcomes in patients with angina pectoris and normal ejection fraction.
Coron. Artery Dis.
PUBLISHED: 11-06-2014
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Although inappropriate left ventricular mass has been associated with clustered cardiac geometric and functional abnormalities, its predictive value in patients with coronary artery disease is still unknown. This study examined the association of inappropriate left ventricular mass with clinical outcomes in patients with angina pectoris and normal ejection fraction.
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Effects of Callistephus chinensis flower polyphones on improving metabolic disorders in high-fat diet-induced mice.
Food Funct
PUBLISHED: 11-04-2014
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The aim of this study was to investigate the effects of Callistephus chinensis flower (CCF) polyphones on symptoms of metabolic syndrome in a newly developed high-fat diet-induced non-alcoholic fatty liver disease (NAFLD) mouse model. C57BL/6J mice were fed a high fat diet (HFD; 50% energy as fat) with normal drinking fluid or HFD with CCF polyphones (50 mg L(-1) or 100 mg L(-1)) in drinking fluid for 12 weeks. As a comparison, mice fed a normal-fat (NFD; 10% energy as fat) and with normal drinking fluid were also included. The HFD group developed more severe symptoms of metabolic syndrome than the NFD group. CCF polyphones treatment significantly reduced fecal lipids compared to the HFD group, suggesting a strong indication of improved lipid metabolism. Liver damage and liver triglyceride levels were also decreased by CCF polyphones treatment. Moreover, both morphologic and histological detections indicated that CCF polyphones significantly reversed HFD-induced hepatic steatosis and liver injury. Furthermore, CCF polyphones significantly ameliorated both HFD-induced metabolic disorders, such as insulin resistance, and inflammatory cytokines, including interlukin-6 (IL-6) and tumor necrosis factor-? (TNF-?). Moreover, hepatic peroxisome proliferator-activated receptor (PPAR?) and the gene involved in PPAR?, Peroxisomal acyl-CoA oxidase (ACOX), were markedly up-regulated at protein levels by CCF polyphones. Our results demonstrate that the HFD produces metabolic syndrome of NAFLD, and CCF polyphones treatment can alleviate these symptoms. The beneficial effects of CCF polyphones are associated with improved lipid metabolism and reduced levels of inflammatory cytokines.
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First Succinyl-Proteome Profiling of Extensively Drug-Resistant Mycobacterium tuberculosis Revealed Involvement of Succinylation in Cellular Physiology.
J. Proteome Res.
PUBLISHED: 11-04-2014
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Protein lysine succinylation, an emerging protein post-translational modification widespread among eukaryotic and prokaryotic cells, represents an important regulator of cellular processes. However, the extent and function of lysine succinylation in Mycobacterium tuberculosis, especially extensively drug-resistant strain, remain elusive. Combining protein/peptide prefractionation, immunoaffinity enrichment, and LC-MS/MS analysis, a total of 686 succinylated proteins and 1739 succinylation sites of M. tuberculosis were identified, representing the first global profiling of M. tuberculosis lysine succinylation. The identified succinylated proteins are involved in a variety of cellular functions such as metabolic processes, transcription, translation, and stress responses and exhibit different subcellular localization via GO, protein interaction network, and other bioinformatic analysis. Notably, proteins involved in protein biosynthesis and carbon metabolism are preferred targets of lysine succinylation. Moreover, two prevalent sequence patterns: EK(suc) and K*****K(suc), can be found around the succinylation sites. There are 109 lysine-succinylated homologues in E. coli, suggesting highly conserved succinylated proteins. Succinylation was found to occur at the active sites predicted by Prosite signature including Rv0946c, indicating that lysine succinylation may affect their activities. There is extensive overlapping between acetylation sites and succinylation sites in M. tuberculosis. Many M. tuberculosis metabolic enzymes and antibiotic resistance proteins were succinylated. This study provides a basis for further characterization of the pathophysiological role of lysine succinylation in M. tuberculosis.
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Weakly Supervised Visual Dictionary Learning by Harnessing Image Attributes.
IEEE Trans Image Process
PUBLISHED: 11-01-2014
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Bag-of-Features (BoF) representation has been extensively applied to deal with various computer vision applications. To extract discriminative and descriptive BoF, one important step is to learn a good dictionary to minimize the quantization loss between local features and codewords. While most existing visual dictionary learning approaches are engaged with unsupervised feature quantization, the latest trend has turned to supervised learning by harnessing the semantic labels of images or regions. However, such labels are typically too expensive to acquire, which restricts the scalability of supervised dictionary learning approaches. In this paper, we propose to leverage image attributes to "weakly supervise" the dictionary learning procedure without requiring any actual labels. As a key contribution, our approach establishes a generative Hidden Markov Random Field (HMRF) which models the quantized codewords as the observed states and the image attributes as the hidden states, respectively. Dictionary learning is then performed by supervised grouping the observed states, where the supervised information is stemmed from the hidden states of the HMRF. In such a way, the proposed dictionary learning approach incorporates the image attributes to learn a semanticpreserving BoF representation without any genuine supervision. Experiments in large-scale image retrieval and classification tasks corroborate that our approach significantly outperforms the state-of-the-art unsupervised dictionary learning approaches.
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4D ACTIVE CUT: AN INTERACTIVE TOOL FOR PATHOLOGICAL ANATOMY MODELING.
Proc IEEE Int Symp Biomed Imaging
PUBLISHED: 10-31-2014
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4D pathological anatomy modeling is key to understanding complex pathological brain images. It is a challenging problem due to the difficulties in detecting multiple appearing and disappearing lesions across time points and estimating dynamic changes and deformations between them. We propose a novel semi-supervised method, called 4D active cut, for lesion recognition and deformation estimation. Existing interactive segmentation methods passively wait for user to refine the segmentations which is a difficult task in 3D images that change over time. 4D active cut instead actively selects candidate regions for querying the user, and obtains the most informative user feedback. A user simply answers 'yes' or 'no' to a candidate object without having to refine the segmentation slice by slice. Compared to single-object detection of the existing methods, our method also detects multiple lesions with spatial coherence using Markov random fields constraints. Results show improvement on the lesion detection, which subsequently improves deformation estimation.
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[Clinical features of oral lesions in patients with human immunodeficiency virus infection/acquired immunodeficiency syndrome in Guangxi autonomous region].
Zhonghua Kou Qiang Yi Xue Za Zhi
PUBLISHED: 10-30-2014
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To investigate the features of oral lesions in patients with human immunodeficiency virus infection/acquired immunodeficiency syndrome (HIV/AIDS).
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[Long term follow-up and prognostic analysis of 85 cases with primary gastrointestinal diffuse large B cell lymphoma].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 10-24-2014
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To analyze the clinical characteristics, prognostic factors in patients with primary gastrointestinal diffuse large B cell lymphoma (PGI-DLBCL).
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NLRP3 Inflammasome Activation Is Essential for Paraquat-Induced Acute Lung Injury.
Inflammation
PUBLISHED: 10-24-2014
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The innate immune response is important in paraquat-induced acute lung injury, but the exact pathways involved are not elucidated. The objectives of this study were to determine the specific role of the NLRP3 inflammasome in the process. Acute lung injury was induced by administering paraquat (PQ) intraperitoneally. NLRP3 inflammasome including NLRP3, ASC, and caspase-1 mRNA and protein expression in lung tissue and IL-1? and IL-18 levels in BALF were detected at 4, 8, 24, and 72 h after PQ administration in rats. Moreover, rats were pretreated with 10, 30, and 50 mg/kg NLRP3 inflammasome blocker glybenclamide, respectively, 1 h before PQ exposure. At 72 h after PQ administration, lung histopathology changes, NLRP3, ASC, and caspase-1 protein expression, as well as secretion of cytokines including IL-1? and IL-18 in BALF were investigated. The NLRP3 inflammasome including NLRP3, ASC, caspase-1 expression, and cytokines IL-1? and IL-18 levels in PQ poisoning rats were significantly higher than that in the control group. NLRP3 inflammasome blocker glybenclamide pretreatment attenuated lung edema, inhibited the NLRP3, ASC, and caspase-1 activation, and reduced IL-1? and IL-18 levels in BALF. In the in vitro experiments, IL-1? and IL-18 secreted from RAW264.7 mouse macrophages treated with paraquat were attenuated by glybenclamide. In conclusion, paraquat can induce IL-1?/IL-18 secretion via NLRP3-ASC-caspase-1 pathway, and the NLRP3 inflammasome is essential for paraquat-induced acute lung injury.
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Stripe Rust Resistance Gene Yr10 Encodes an Evolutionary-conserved and Unique CC-NBS-LRR Sequence in Wheat.
Mol Plant
PUBLISHED: 10-23-2014
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The first seedling or all stage resistance R gene against stripe rust isolated from Moro wheat (Triticum aestivum L.) using a map-based cloning approach was identified as Yr10. Clone 4B of this gene encodes a highly evolutionary-conserved and unique CC-NBS-LRR sequence. Clone 4E, a homolog of Yr10, but lacking TSS and putative TATA-box and CAAT-box is likely a non-expressed pseudogene. Clones 4B and 4E are 84% are identical and divergent in the intron and the LRR domain. Gene silencing and transgenesis were used in conjunction with inoculation with differentially avirulent and virulent stripe rust strains to demonstrate Yr10 functionality. The Yr10 CC-NBS-LRR sequence is unique among known CC-NBS-LRR R-genes in wheat but highly conserved homologs (E = 0.0) were identified in Aegilops tauschii and other monocots including Hordeum vulgare and Brachypodium distachyon. Related sequences were also identified in genomic databases of maize, rice and in sorghum. This is the first report of a CC-NBS-LRR resistance gene in plants with limited homologies in its native host, but with numerous homologous R-genes in related monocots that are either host or non-hosts for stripe rust. These results represent a unique example about gene evolution and dispersion across species.
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lncRNASNP: a database of SNPs in lncRNAs and their potential functions in human and mouse.
Nucleic Acids Res.
PUBLISHED: 10-22-2014
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Long non-coding RNAs (lncRNAs) play key roles in various cellular contexts and diseases by diverse mechanisms. With the rapid growth of identified lncRNAs and disease-associated single nucleotide polymorphisms (SNPs), there is a great demand to study SNPs in lncRNAs. Aiming to provide a useful resource about lncRNA SNPs, we systematically identified SNPs in lncRNAs and analyzed their potential impacts on lncRNA structure and function. In total, we identified 495 729 and 777 095 SNPs in more than 30 000 lncRNA transcripts in human and mouse, respectively. A large number of SNPs were predicted with the potential to impact on the miRNA-lncRNA interaction. The experimental evidence and conservation of miRNA-lncRNA interaction, as well as miRNA expressions from TCGA were also integrated to prioritize the miRNA-lncRNA interactions and SNPs on the binding sites. Furthermore, by mapping SNPs to GWAS results, we found that 142 human lncRNA SNPs are GWAS tagSNPs and 197 827 lncRNA SNPs are in the GWAS linkage disequilibrium regions. All these data for human and mouse lncRNAs were imported into lncRNASNP database (http://bioinfo.life.hust.edu.cn/lncRNASNP/), which includes two sub-databases lncRNASNP-human and lncRNASNP-mouse. The lncRNASNP database has a user-friendly interface for searching and browsing through the SNP, lncRNA and miRNA sections.
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The risk of carcinogenesis in congenital choledochal cyst patients: an analysis of 214 cases.
Ann Hepatol
PUBLISHED: 10-22-2014
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Background. Choledochal cysts are most common in Asian populations. In addition, the incidence of biliary tract malignancies from choledochal cysts is increasing, but the risk of carcinogenesis is still unclear. Material and methods. Clinical data from 214 congenital choledochal cyst cases from 1968 to 2013 were retrospectively analyzed. Results. Todani type I was more common (139, 65.0%) than type IVa (53, 24.8%) or type V (17, 7.9%) in these choledochal cyst patients. Biliary tract malignant tumors occurred in the gallbladder (2, 13.3%), common bile duct (10, 66.7%), and intrahepatic bile duct (3, 20%) in 15 patients (7.0%), including one patient in whom malignant transformation occurred in the intrahepatic bile duct in a type IVa patient 15 years after extrahepatic cyst resection. An age at symptom onset ? 60 years was a risk factor (p < 0.001), while an initial complete surgery was a protective factor for carcinogenesis (p = 0.001). Conclusions. Choledochal cysts should be removed once diagnosed because of an increased risk of malignant transformation with increasing age. Complete cyst removal is necessary for the first surgical treatment. Additional hepatectomy should be considered for type IVa choledochal cysts because cholangiocarcinoma can arise from the intrahepatic bile duct years after the extrahepatic cyst excision.
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[The construction and application of a novel apparatus for detecting oxygen consumption of mice under normobaric hypoxia].
Zhongguo Ying Yong Sheng Li Xue Za Zhi
PUBLISHED: 10-22-2014
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To establish a method for real-time recording the oxygen consumption of mice under normobaric hypoxia.
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Efficacy of a Tobacco Quitline Among Adult Survivors of Childhood Cancer.
Nicotine Tob. Res.
PUBLISHED: 10-21-2014
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The purpose of this investigation was to determine the efficacy of two evidence-based tobacco quitlines in adult survivors of childhood cancer who regularly smoke cigarettes.
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Use of vacuum bagging for fabricating thermoplastic microfluidic devices.
Lab Chip
PUBLISHED: 10-21-2014
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In this work we present a novel thermal bonding method for thermoplastic microfluidic devices. This simple method employs a modified vacuum bagging technique, a concept borrowed from the aerospace industry, to produce conventional thick substrate microfluidic devices, as well as multi-layer film devices. The bonds produced using this method are superior to those obtained using conventional thermal bonding methods, including thermal lamination, and are capable of sustaining burst pressures in excess of 550 kPa. To illustrate the utility of this method, thick substrate devices were produced, as well as a six-layer film device that incorporated several complex features.
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Dopamine release from transplanted neural stem cells in Parkinsonian rat striatum in vivo.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 10-20-2014
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Embryonic stem cell-based therapies exhibit great potential for the treatment of Parkinson's disease (PD) because they can significantly rescue PD-like behaviors. However, whether the transplanted cells themselves release dopamine in vivo remains elusive. We and others have recently induced human embryonic stem cells into primitive neural stem cells (pNSCs) that are self-renewable for massive/transplantable production and can efficiently differentiate into dopamine-like neurons (pNSC-DAn) in culture. Here, we showed that after the striatal transplantation of pNSC-DAn, (i) pNSC-DAn retained tyrosine hydroxylase expression and reduced PD-like asymmetric rotation; (ii) depolarization-evoked dopamine release and reuptake were significantly rescued in the striatum both in vitro (brain slices) and in vivo, as determined jointly by microdialysis-based HPLC and electrochemical carbon fiber electrodes; and (iii) the rescued dopamine was released directly from the grafted pNSC-DAn (and not from injured original cells). Thus, pNSC-DAn grafts release and reuptake dopamine in the striatum in vivo and alleviate PD symptoms in rats, providing proof-of-concept for human clinical translation.
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DNA damage and oxidative stress induced by CeO2 nanoparticles in human dermal fibroblasts: Evidence of a clastogenic effect as a mechanism of genotoxicity.
Nanotoxicology
PUBLISHED: 10-18-2014
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Abstract The broad range of applications of cerium oxide (CeO2) nanoparticles (nano-CeO2) has attracted industrial interest, resulting in greater exposures to humans and environmental systems in the coming years. Their health effects and potential biological impacts need to be determined for risk assessment. The aims of this study were to gain insights into the molecular mechanisms underlying the genotoxic effects of nano-CeO2 in relation with their physicochemical properties. Primary human dermal fibroblasts were exposed to environmentally relevant doses of nano-CeO2 (mean diameter, 7?nm; dose range, 6?×?10(-5)-6?×?10(-3)?g/l corresponding to a concentration range of 0.22-22?µM) and DNA damages at the chromosome level were evaluated by genetic toxicology tests and compared to that induced in cells exposed to micro-CeO2 particles (mean diameter, 320?nm) under the same conditions. For this purpose, cytokinesis-blocked micronucleus assay in association with immunofluorescence staining of centromere protein A in micronuclei were used to distinguish between induction of structural or numerical chromosome changes (i.e. clastogenicity or aneuploidy). The results provide the first evidence of a genotoxic effect of nano-CeO2, (while not significant with micro-CeO2) by a clastogenic mechanism. The implication of oxidative mechanisms in this genotoxic effect was investigated by (i) assessing the impact of catalase, a hydrogen peroxide inhibitor, and (ii) by measuring lipid peroxidation and glutathione status and their reversal by application of N-acetylcysteine, a precusor of glutathione synthesis in cells. The data are consistent with the implication of free radical-related mechanisms in the nano-CeO2-induced clastogenic effect, that can be modulated by inhibition of cellular hydrogen peroxide release.
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Analysis of noisy multi-angle dynamic light scattering data.
Appl Opt
PUBLISHED: 10-17-2014
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In multi-angle dynamic light scattering measurements, due to the inevitable presence of baseline measurement noise, the normalized intensity autocorrelation function (ACF) data deviates from the true value. This leads to incorrect angular weighting estimates, which affect the accuracy of inversion results and determination of particle size distributions (PSDs). We outline a method to calculate better angular weighting coefficients from the noisy intensity ACF data. The method involves first compensating for the baseline error in the ACF data and then determining the weighting coefficients. We demonstrate the method using simulated ACF data containing baseline error for unimodal and bimodal PSDs and also for experimental data for unimodal and bimodal samples. For the unimodal PSDs ACF data were simulated for 100-900 nm and 100-650 nm particle size ranges, and for bimodal PSDs 360-900 nm and 100-900 nm particle size ranges were used. The performance of our method was shown by comparing the results of weighting coefficient and PSD determination with and without baseline compensation to the known coefficient values and PSDs. With baseline compensation the relative error of the weighting coefficients decreased significantly. Furthermore, with baseline compensation, the PSD results for the four groups of simulated data were improved. The deviations between the known and recovered PSDs were decreased, the relative error of peak position obviously decreased, and the occurrence of false peaks was reduced. The PSD results from the experimental data further validates the conclusion that the method proposed apparently reduces the relative error of peak position, effectively eliminates the false peak, and improves the accuracy of the recovered PSD.
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Scalable histopathological image analysis via active learning.
Med Image Comput Comput Assist Interv
PUBLISHED: 10-17-2014
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Training an effective and scalable system for medical image analysis usually requires a large amount of labeled data, which incurs a tremendous annotation burden for pathologists. Recent progress in active learning can alleviate this issue, leading to a great reduction on the labeling cost without sacrificing the predicting accuracy too much. However, most existing active learning methods disregard the "structured information" that may exist in medical images (e.g., data from individual patients), and make a simplifying assumption that unlabeled data is independently and identically distributed. Both may not be suitable for real-world medical images. In this paper, we propose a novel batch-mode active learning method which explores and leverages such structured information in annotations of medical images to enforce diversity among the selected data, therefore maximizing the information gain. We formulate the active learning problem as an adaptive submodular function maximization problem subject to a partition matroid constraint, and further present an efficient greedy algorithm to achieve a good solution with a theoretically proven bound. We demonstrate the efficacy of our algorithm on thousands of histopathological images of breast microscopic tissues.
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Towards Large-Scale Histopathological Image Analysis: Hashing-Based Image Retrieval.
IEEE Trans Med Imaging
PUBLISHED: 10-15-2014
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Automatic analysis of histopathological images has been widely utilized leveraging computational image-processing methods and modern machine learning techniques. Both computer-aided diagnosis (CAD) and content-based imageretrieval (CBIR) systems have been successfully developed for diagnosis, disease detection, and decision support in this area. Recently, with the ever-increasing amount of annotated medical data, large-scale and data-driven methods have emerged to offer a promise of bridging the semantic gap between images and diagnostic information. In this paper, we focus on developing scalable image-retrieval techniques to cope intelligently with massive histopathological images. Specifically, we present a supervised kernel hashing technique which leverages a small amount of supervised information in learning to compress a 10,000-dimensional image feature vector into only tens of binary bits with the informative signatures preserved. These binary codes are then indexed into a hash table that enables real-time retrieval of images in a large database. Critically, the supervised information is employed to bridge the semantic gap between low-level image features and high-level diagnostic information. We build a scalable image-retrieval framework based on the supervised hashing technique and validate its performance on several thousand histopathological images acquired from breast microscopic tissues. Extensive evaluations are carried out in terms of image classification (i.e., benign vs. actionable categorization) and retrieval tests. Our framework achieves about 88:1% classification accuracy as well as promising time efficiency. For example, the framework can execute around 800 queries in only 0:01 seconds, comparing favorably with other commonly used dimensionality reduction and feature selection methods.
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[Gene mutations and clinical features of adult vitelliform macular dystrophy in 5 patients].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 10-15-2014
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To describe the clinical features as well as mutations in 2 relative genes in 5 cases with macular dystrophies presenting with vitelliform lesions in adulthood.
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Structural and Mechanistic Insights into NDM-1 Catalyzed Hydrolysis of Cephalosporins.
J. Am. Chem. Soc.
PUBLISHED: 10-07-2014
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Cephalosporins constitute a large class of ?-lactam antibiotics clinically used as antimicrobial drugs. New Dehli metallo-?-lactamase (NDM-1) poses a global threat to human health as it confers on bacterial pathogen resistance to almost all ?-lactams, including penicillins, cephalosporins, and carbapenems. Here we report the first crystal structures of NDM-1 in complex with cefuroxime and cephalexin, as well as NMR spectra monitoring cefuroxime and cefixime hydrolysis catalyzed by NDM-1. Surprisingly, cephalosporoate intermediates were captured in both crystal structures determined at 1.3 and 2.0 Å. These results provide detailed information concerning the mechanism and pathways of cephalosporin hydrolysis. We also present the crystal structure and enzyme assays of a D124N mutant, which reveals that D124 most likely plays a more structural than catalytic role.
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Fast in situ generated ?-polylysine-poly (ethylene glycol) hydrogels as tissue adhesives and hemostatic materials using an enzyme-catalyzed method.
J Biomater Appl
PUBLISHED: 10-05-2014
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In this study, novel bio-inspired in situ hydrogels as tissue adhesives and hemostatic materials were designed and prepared based on ?-polylysine-grafted poly(ethylene glycol) and tyramine via enzymatic cross-linking. The enzymatic cross-linked method enabled fast gelation within seconds, which facilitated its therapeutic applications. By changing the cross-linking conditions, the storage modulus of the hydrogels could be tunable and the mechanical strength influenced the tissue adhesiveness of the hydrogels. Besides, the hydrogels showed fine network structures with appropriate pore sizes, which were thought to be a contributing factor to the strong adhesiveness. Benefiting from the strong mechanical properties and fine network structures, the ?-polylysine-grafted poly(ethylene glycol) and tyramine hydrogels exhibited superior wound-healing and hemostatic ability compared to conventional and commercially available medical materials. Moreover, indirect cytotoxicity assessment indicated that the ?-polylysine-grafted poly(ethylene glycol) and tyramine hydrogels were nontoxic to the L929 cell. These results demonstrated that the enzymatic cross-linked in situ ?-polylysine hydrogels hold high potential for tissue sealants and hemostatic materials.
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[Effects of plant-derived smoke water on accumulation of biomass and active substance of Salvia miltiorrhiza f. alba].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-04-2014
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To study the effect of plant-derived smoke water on the accumulation of biomass and active substance of Salvia miltiorrhiza f. alba, seedlings of S. miltiorrhiza were treated with different concentrations of smoke water (1:500, 1: 1 000, 1: 2 000). The fresh weight and dry weight of underground part, the number of split-root, maximum root diameter, average root diameter, average root length, the content of lipophilic components and water-soluble components were measured. Results showed that fresh weight and dry weight of underground part were respectively improved by 98.01%, 44.32% and 85.71%, 28.57% with significant difference by smoke water treatment with concentration of 1: 500 and 1: 1 000. Maximum root diameter and dry weight of underground part were respectively enhanced by 58.44% and 85.71% by smoke water with concentration of 1:500. The content of tanshinone I and tanshinone II(A) were improved by smoke water treatment, however there were no significantly difference on the content of cryptotanshinone and dihydrotan shinone. This study indicates that smoke water treatment could be used to improve the accumulation of biomass and active substance content of S. miltiorrhiza f. alba, which could provide new ideas for its green cultivating.
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A broadband microwave Corbino spectrometer at ³He temperatures and high magnetic fields.
Rev Sci Instrum
PUBLISHED: 10-03-2014
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We present the technical details of a broadband microwave spectrometer for measuring the complex conductance of thin films covering the range from 50 MHz up to 16 GHz in the temperature range 300 mK-6 K and at applied magnetic fields up to 8 T. We measure the complex reflection from a sample terminating a coaxial transmission line and calibrate the signals with three standards with known reflection coefficients. Thermal isolation of the heat load from the inner conductor is accomplished by including a section of NbTi superconducting cable (transition temperature around 8-9 K) and hermetic seal glass bead adapters. This enables us to stabilize the base temperature of the sample stage at 300 mK. However, the inclusion of this superconducting cable complicates the calibration procedure. We document the effects of the superconducting cable on our calibration procedure and the effects of applied magnetic fields and how we control the temperature with great repeatability for each measurement. We have successfully extracted reliable data in this frequency, temperature, and field range for thin superconducting films and highly resistive graphene samples.
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[Rapid quantitative analysis of hydrocarbon composition of furfural extract oils using attenuated total reflection infrared spectroscopy].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-02-2014
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A set of rapid analysis system for hydrocarbon composition of heavy oils was designed using attenuated total reflection FTIR spectrometer and chemometrics to determine the hydrocarbon composition of furfural extract oils. Sixty two extract oil samples were collected and their saturates and aromatics content data were determined according to the standard NB/SH/T0509-2010, then the total contents of resins plus asphaltenes were calculated by the subtraction method in the percentage of weight. Based on the partial least squares (PLS), calibration models for saturates, aromatics, and resin+asphaltene contents were established using attenuated total reflection FTIR spectroscopy, with their SEC, 1.43%, 0.91% and 1.61%, SEP, 1.56%, 1.24% and 1.81%, respectively, meeting the accuracy and repeatability required for the standard. Compared to the present standard method, the efficiency of hydrocarbon composition analysis for furfural extract oils is significantly improved by the new method which is rapid and simple. The system could also be used for other heavy oil analysis, with excellent extension and application foreground.
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Extrathyroidal implantation of thyroid hyperplastic/neoplastic cells after endoscopic thyroid surgery.
Chin. Med. Sci. J.
PUBLISHED: 09-30-2014
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To report a case of the implantation of thyroid hyperplastic or neoplastic tissue after endoscopic thyroidectomy and discuss this complication in aspects of prevalence, pathogenesis, protection, and therapies.
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AnimalTFDB 2.0: a resource for expression, prediction and functional study of animal transcription factors.
Nucleic Acids Res.
PUBLISHED: 09-29-2014
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Transcription factors (TFs) are key regulators for gene expression. Here we updated the animal TF database AnimalTFDB to version 2.0 (http://bioinfo.life.hust.edu.cn/AnimalTFDB/). Using the improved prediction pipeline, we identified 72 336 TF genes, 21 053 transcription co-factor genes and 6502 chromatin remodeling factor genes from 65 species covering main animal lineages. Besides the abundant annotations (basic information, gene model, protein functional domain, gene ontology, pathway, protein interaction, ortholog and paralog, etc.) in the previous version, we made several new features and functions in the updated version. These new features are: (i) gene expression from RNA-Seq for nine model species, (ii) gene phenotype information, (iii) multiple sequence alignment of TF DNA-binding domains, and the weblogo and phylogenetic tree based on the alignment, (iv) a TF prediction server to identify new TFs from input sequences and (v) a BLAST server to search against TFs in AnimalTFDB. A new nice web interface was designed for AnimalTFDB 2.0 allowing users to browse and search all data in the database. We aim to maintain the AnimalTFDB as a solid resource for TF identification and studies of transcription regulation and comparative genomics.
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[Transnasal endoscopic choanal plasty for repairing congenital choanal atresia].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-27-2014
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To observe the effect of transnasal endoscopic choanal plasty for repairing congenital choanal atresia.
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R-spondin1 is a novel hormone mediator for mammary stem cell self-renewal.
Genes Dev.
PUBLISHED: 09-26-2014
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Signals from the niche play pivotal roles in regulating adult stem cell self-renewal. Previous studies indicated that the steroid hormones can expand mammary stem cells (MaSCs) in vivo. However, the facilitating local niche factors that directly contribute to the MaSC expansion remain unclear. Here we identify R-spondin1 (Rspo1) as a novel hormonal mediator in the mammary gland. Pregnancy and hormonal treatment up-regulate Rspo1 expression. Rspo1 cooperates with another hormonal mediator, Wnt4, to promote MaSC self-renewal through Wnt/?-catenin signaling. Knockdown of Rspo1 and Wnt4 simultaneously abolishes the stem cell reconstitution ability. In culture, hormonal treatment that stimulates the expression of both Rspo1 and Wnt4 can completely substitute for exogenous Wnt proteins, potently expand MaSCs, and maintain their full development potential in transplantation. Our data unveil the intriguing concept that hormones induce a collaborative local niche environment for stem cells.
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Hypoglycemic, hypolipidemic and antioxidant effects of Sarcandra glabra polysaccharide in type 2 diabetic mice.
Food Funct
PUBLISHED: 09-26-2014
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Sarcandra glabra (Thunb.) Nakai is a traditional Chinese herbal medicine and dietary supplement used for treating several diseases. The anti-diabetic activity of S. glabra polysaccharides is reported for the first time. The in vitro ?-glucosidase inhibition assay indicated that the acidic S. glabra polysaccharide (SGP-2) has an IC50 of 87.06 ± 11.76 ?g mL(-1), which was much lower than acarbose at 338.90 ± 46.86 ?g mL(-1). Moreover, high fat diet (HFD) with streptozotocin (STZ) induced diabetic mice were administered SGP-2 (150, 300, or 600 mg kg(-1) per day, respectively) for 3 weeks. Postprandial blood glucose levels (PBGL), total cholesterol, triglyceride and free fatty acid levels in diabetic mice treated with SGP-2 were significantly decreased (p < 0.05) compared to those of the model group. The results of the oral glucose tolerance test (OGTT) and the homeostasis model assessment-insulin resistance (HOMA-IR) index indicated that SGP-2 could significantly improve (p < 0.05) the insulin resistance and glucose tolerance in diabetic mice. Furthermore, the activities of antioxidant enzymes, hexokinase and pyruvate kinase were significantly increased (p < 0.05) in SGP-2 treated groups. Thus we proposed that SGP-2 exerted hypoglycemic activity by relieving insulin resistance, reducing postprandial blood glucose levels and ameliorating lipid metabolism, as well as alleviating oxidative stress. These data suggested that SGP-2 with anti-hyperglycemic activity could be used in medicinal preparations for diabetes mellitus and its complications.
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Influence of Chm-I knockout on ectopic cartilage regeneration and homeostasis maintenance.
Tissue Eng Part A
PUBLISHED: 09-25-2014
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Ectopic ossification of mesenchymal stem cell (MSC) regenerated cartilage have greatly restricted its application in repairing subcutaneous cartilage defects (such as nasal or auricular). Different from MSCs, chondrocytes can maintain stable chondrogenic phenotype in ectopic microenvironment, which was speculated to be related with the existence of anti-angiogenic factors such as Chondromodulin-I (Chm-I). Therefore, the purpose of this study was to illustrate whether Chm-I was indispensable for stable ectopic chondrogenesis by chondrocyte, which may help to solve the problem of MSC ectopic ossification in future. The current study demonstrated that Chm-I knockout did not obviously influence articular cartilage development in situ. However, native articular cartilage from Chm-I knockout (Chm-I-/-, KO) but not wild type (WT) mice showed obvious ossification after subcutaneously implanted into nude mice for 16 d. Interestingly, cell morphology, cartilage specific matrix expression, and pellet culture demonstrated that Chm-I knockout had no obvious influence on phenotype, function, and chondrogenic ability of chondrocytes in vitro, except that cells in WT group proliferated a little faster than those in KO group. Nevertheless, Chm-I knockout directly interfered with in vivo ectopic cartilage regeneration when chondrocytes were subcutaneously injected into nude mice with matrigel. Moreover, Chm-I knockout obviously compromised ectopic stability of in vitro regenerated cartilage after subcutaneous implantation. These findings indicated that Chm-I was an indispensable factor for ectopic cartilage regeneration and the maintenance of cartilage homeostasis, which may provide a clue for solving the stability problem of MSC regenerated cartilage in ectopic niche. In addition, this study also provides a novel model based on tissue engineering strategy to properly evaluate the function of other targeted genes.
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[Chronic disseminated intravascular coagulopathy associated with aortic dissecting aneurysms: two cases report and literature review].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 09-24-2014
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To report two cases of chronic disseminated intravascular coagulation associated (DIC) with aortic dissecting aneurysm, and discuss the treatment strategy.
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[The effect of hypothermia on the vasoconstriction and vasodilatation and concerned with vasoactive drugs].
Zhongguo Ying Yong Sheng Li Xue Za Zhi
PUBLISHED: 09-24-2014
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To investigate the changes of vasoconstriction and vasodilatation under different temperature conditions and the protective effects of Vitamin E (Vit E) against endothelial injury induced by hypothermia.
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Structural evolution of NiAu nanoparticles under ambient conditions directly revealed by atom-resolved imaging combined with DFT simulation.
Nanoscale
PUBLISHED: 09-19-2014
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From an economic point of view, the structural stability of noble-transition bimetallic catalysts is as significant as their well-studied catalytic efficiency. The structural evolution and corresponding dynamics of NiAu bimetallic nanoparticles under ambient conditions are investigated using in situ Cs-corrected STEM and DFT calculations. During oxidization, the Au component promotes dissociation of oxygen and initiates Ni oxidization, which simultaneously drives the migration of Au atoms, thus yielding multi-shell structures (denoted by Ni@Au@NiO). The subsequent hydrogen reduction induces surface reconstruction, forming fcc-NiAu clusters. After several cycles of catalyzing CO oxidization, both inverse Au segregation and Ni recrystallization occur, which are ascribed to exothermic excitation. The results of this study can help researchers understand the evolutionary behaviors of the bimetallic nanoparticles under ambient conditions as well as optimize the structural design of bimetallic catalysts.
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Association between the XRCC1 Arg194Trp polymorphism and glioma risk: an updated meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-18-2014
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Gliomas are the most common type of primary brain tumors. The XRCC1 Arg194Trp variant affects the proliferating cell nuclear antigen( PCNA) binding region, which suggests that this mutation may contribute to gliomagenesis and a number of articles have examine the association between XRCC1 Arg194Trp and the susceptibility to glioma. However, the results were conflicting. Test of heterogeneity, sensitivity analysis, meta- analysis, and assessment of publication bias were all performed in our present meta-analysis, covering a total of 5,407 patients and 7,715 healthy persons. In the overall analysis the XRCC1 Arg194Trp polymorphism showed a significant association with glioma susceptibility in a recessive mode l(for TrpTrp vs ArgArg+ArgTrp: OR=1.918, 95%CI=1.575-2.336, I2=2.3%). In addition, analysis of subgroups presented an increased risk in Asians and populations-based on hospitals. The results suggested that the XRCC1 Arg194Trp polymorphism is a genetic risk factor for glioma, especially in Asian population. To further evaluate gene-gene and gene-environment interactions on XRCC1 polymorphisms and glioma risk, thousands of subjects and tissue-specific biochemical characterizations are required.
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Overcoming 5-Fu resistance of colon cells through inhibition of Glut1 by the specific inhibitor WZB117.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-18-2014
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5-Fluorouracil (5-FU) is the most commonly used drug in colon cancer therapy. However, despite impressive clinical responses initially, development of drug resistance to 5-Fu in human tumor cells is the primary cause of failure of chemotherapy. In this study, we established a 5-Fu-resistant human colon cancer cell line for comparative chemosensitivity studies.
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Cumulative alkylating agent exposure and semen parameters in adult survivors of childhood cancer: a report from the St Jude Lifetime Cohort Study.
Lancet Oncol.
PUBLISHED: 09-16-2014
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Few data define the dose-specific relation between alkylating agent exposure and semen variables in adult survivors of childhood cancer. We undertook this study to test the hypothesis that increased exposure to alkylating agents would be associated with decreased sperm concentration in a cohort of adult male survivors of childhood cancer who were not exposed to radiation therapy for their childhood cancer.
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PD806: a novel oral vascular disrupting agent shows antitumor and antivascular effects in vitro and in vivo.
Anticancer Drugs
PUBLISHED: 09-16-2014
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The aim of this study was to investigate the antitumor and antivascular effects of PD806, a new oral prodrug of AVE8063 in vitro and in vivo. The cytotoxicity of PD806 was determined against H22, Walker 256, A549, MCF-7, and BEL-7402 cells using MTT assays. Plasma pharmacokinetic analysis of AVE8063 generated in rats after a single oral administration of PD806 was carried out using the high-performance liquid chromatography method. H22 tumor-bearing mice models were used to show the antitumor activity. Antivascular responses were monitored by in vivo MRI and immunohistochemistry (CD31) in W256 tumor-bearing rats. A blood test and histopathology were performed to evaluate the toxicity of PD806. PD806 showed cytotoxicity against five types of tumor cell lines with the IC50 values in the micromolar concentration. A pharmacokinetic study indicated that PD806 converted into the active form, AVE8063, which showed a half-life of 5.24±0.70?h in rats. Daily oral administration of PD806 inhibited the growth of subcutaneously implanted H22 tumors in a dose-dependent manner. The tumor volume in the 300?mg/kg PD806 group was obviously smaller than that of the vehicle control group from day 6 onward (P<0.05), with inhibition rates of 62% on day 30. PD806 in the three-dose group significantly prolonged the survival of the H22 tumor-bearing mice (P<0.05). At 24?h after PD806 (150 and 200?mg/kg) was administered orally, tumor vascular shutdown was found on CE-T1WI with the presence of extended necrosis and tumor residue at the periphery. The enhancement ratio decreased significantly from 1.00±0.00 at baseline to 0.26±0.08 and 0.17±0.06, respectively (P<0.01). The necrosis ratio measured from CE-T1WI increased significantly from 34% in average at baseline to 52.96 and 60.30%, respectively (P<0.05). Immunohistochemical staining of tumor sections showed a marked reduction in CD31 staining vessels, with microvessel density reduced significantly to 8.71±1.76 and 3.33±1.04, respectively, compared with the vehicle control group (P<0.01). The results of hematology and histopathology showed that PD806 exerted no obvious toxicity during the treatment period. In conclusion, our results indicate that PD806 is an effective and safe vascular disrupting agent.
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Exploring variations in functional connectivity of the resting state default mode network in mild traumatic brain injury.
Brain Connect
PUBLISHED: 09-16-2014
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A definitive diagnosis of mTBI is difficult due to the absence of biomarkers in standard clinical imaging. The brain is a complex network of interconnected neurons and subtle changes can modulate key networks of cognitive function. The resting state default mode network (DMN) has been shown to be sensitive to changes induced by pathology. This study seeks to determine if quantitative measures of the DMN are sensitive in distinguishing mTBI subjects. Resting state fMRI data were obtained for healthy (N=12) and mTBI subjects (N=15). DMN maps were computed using dual-regression independent component analysis (ICA). A goodness-of-fit index (GOF) was calculated to assess the degree of spatial specificity and sensitivity between healthy controls and mTBI subjects. DMN regions and neuropsychological assessments were examined to identify potential relationships. The resting state DMN maps indicate an increase in spatial co-activity in mTBI subjects within key regions of the DMN. Significant co-activity within the cerebellum and supplementary motor areas of mTBI subjects were also observed. This has not been previously reported in seed-based resting state network analysis. The GOF suggested the presence of high variability within the mTBI subject group, with poor sensitivity and specificity. The neuropsychological data showed correlations between areas of co-activity within the resting state network in the brain with a number of measures of emotion and cognitive functioning. The poor performance of the GOF highlights the key challenge associated with mTBI injury: the high variability in injury mechanisms and subsequent recovery. However, the quantification of the DMN using dual regression ICA has potential to distinguish mTBI from healthy subjects, and provide information on the relationship of aspects of cognitive and emotional functioning with their potential neural correlates.
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Systematic Approach in Designing Rare-Earth-Free Hybrid Semiconductor Phosphors for General Lighting Applications.
J. Am. Chem. Soc.
PUBLISHED: 09-13-2014
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As one of the most rapidly evolving branches of solid-state lighting technologies, light emitting diodes (LEDs) are gradually replacing conventional lighting sources due to their advantages in energy saving and environmental protection. At the present time, commercially available white light emitting diodes (WLEDs) are predominantly phosphor based (e.g., a yellow-emitting phosphor, such as cerium-doped yttrium aluminum garnet or (YAG):Ce(3+), coupled with a blue-emitting InGaN/GaN diode), which rely heavily on rare-earth (RE) metals. To avoid potential supply risks of these elements, we have developed an inorganic-organic hybrid phosphor family based on I-VII binary semiconductors. The hybrid phosphor materials are totally free of rare-earth metals. They can be synthesized by a simple, low-cost solution process and are easily scalable. Their band gap and emission energy, intensity, and color can be systematically tuned by incorporating ligands with suitable electronic properties. High quantum efficiency is achieved for some of these compounds. Such features make this group of materials promising candidates as alternative phosphors for use in general lighting devices.
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Evaluation of Hypericin: Effect of Aggregation on Targeting Biodistribution.
J Pharm Sci
PUBLISHED: 09-12-2014
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Hypericin (Hy) has shown great promise as a necrosis-avid agent in cancer imaging and therapy. Given the highly hydrophobic and ?-conjugated planarity characteristics, Hy tends to form aggregates. To investigate the effect of aggregation on targeting biodistribution, nonaggregated formulation (Non-Ag), aggregated formulation with overconcentrated Hy in dimethyl sulfoxide (Ag-DMSO) solution, and aggregated formulation in water solution (Ag-water) were selected by fluorescence measurement. They were labeled with (131) I and evaluated for the necrosis affinity in rat model of reperfused hepatic infarction by gamma counting and autoradiography. The radioactivity ratio of necrotic liver/normal liver was 17.1, 7.9, and 6.4 for Non-Ag, Ag-DMSO, and Ag-water, respectively. The accumulation of two aggregated formulations (Ag-DMSO and Ag-water) in organs of mononuclear phagocyte system (MPS) was 2.62 ± 0.22 and 3.96 ± 0.30 %ID/g in the lung, and 1.44 ± 0.29 and 1.51 ± 0.23 %ID/g in the spleen, respectively. The biodistribution detected by autoradiography showed the same trend as by gamma counting. In conclusion, the Non-Ag showed better targeting biodistribution and less accumulation in MPS organs than aggregated formulations of Hy. The two aggregated formulations showed significantly lower and higher accumulation in targeting organ and MPS organs, respectively. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci.
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Occurrence and Reassortment of Avian Influenza A (H7N9) Viruses Derived from Coinfected Birds in China.
J. Virol.
PUBLISHED: 09-10-2014
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Over the course of two waves of infection, H7N9 avian influenza A virus has caused 436 human infections and claimed 170 lives in China as of July 2014. To investigate the prevalence and genetic diversity of H7N9, we surveyed avian influenza viruses in poultry in Jiangsu province within the outbreak epicenter. We found frequent occurrence of H7N9/H9N2 coinfection in chickens. Molecular clock phylogenetic analysis confirms coinfection by H7N9/H9N2 viruses and also reveals that the identity of the H7N9 outbreak lineage is confounded by ongoing reassortment between outbreak viruses and diverse H9N2 viruses in domestic birds. Experimental inoculation of a coinfected sample in cell culture yielded two reassortant H7N9 strains with polymerase segments from the original H9N2 strain. Ongoing reassortment between the H7N9 outbreak lineage and diverse H9N2 viruses may generate new strains with the potential to infect humans, highlighting the need for continued viral surveillance in poultry and humans.
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[Effect of the targeted mutation of sorting motifs on the localization of porcine Ia-associated invariant chain].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 09-10-2014
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Objective To investigate the effect of amino acids around two Leu-based motifs (Leu 7/Ile 8 and Met 16/Leu 17) in the cytosolic tail of porcine Ia-associated invariant chain (Ii) on endomembrane system positioning function. Methods At first, two Leu-based motifs and amino acids around motifs were mutated through site-directed mutagenesis of the megaprimer PCR method, and the mutant genes were ligated to the vector pEGFP-C1, respectively. Twenty-one mutations of Ii recombinant plasmid were obtained and transiently transfected into the COS-7 cells by Lipofectamine(TM) 2000. Fluorescence microscopy was used to detect the intracellular localization of mutation Ii. Results Leu 7/Ile 8 and Met 16/Leu 17 independently mediated the intracellular localization of mutation Ii. When one leucine motif was kept and the amino acid around the other leucine motif was mutated, fusion protein GFP-Ii was located in the endomembrane system or distributed in the whole cell. Conclusion pig Ii comprises two independent sorting signals, and the functional Leu-based sorting signal requires specific neighboring residues.
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[Isolation and identification of Myxobacteria strain STXZ54 with antitumor activities].
Wei Sheng Wu Xue Bao
PUBLISHED: 09-10-2014
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We isolated Myxobacteria strains from soil samples collected from Guangzhou, identified the strain and studied the antitumor activity.
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Green electrochemical sensing platforms: utilizing hydroxyapatite derived from natural fish scales as a novel electrochemical material for the sensitive detection of kidney injury molecule 1 (KIM-1).
Analyst
PUBLISHED: 09-06-2014
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Urinary KIM-1 is an ideal biomarker for acute kidney injury diagnosis. The proof-of-concept is demonstrated by utilizing the hydroxyapatite derived from natural fish scales as an electrode material, where the sensing of KIM-1 is shown to be possible for the first time with a linear range from 0.01 to 0.20 ?g mL(-1) and a detection limit of 0.017 ?g mL(-1) under model conditions; proof-of-concept is demonstrated in spiked urine.
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Hierarchical self-assembly of amino acid derivatives into stimuli-responsive luminescent gels.
Soft Matter
PUBLISHED: 09-05-2014
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In this study, unique luminescent gels have been obtained from two components between amino acid functionalized perylene derivatives and 4,4'-bipyridyl units via hierarchical self-assembly. The luminescent gels have been investigated by means of ultraviolet spectra (UV), fluorescence spectra, Scanning Electron Microscopy (SEM) and Laser Scanning Confocal Microscopy (LSCM), which illustrate the strong fluorescence intensity of the gels. In order to further reveal the self-assembly driving forces, the two-dimensional (2D) self-assembly behaviours have been studied by scanning tunneling microscopy (STM) on a highly oriented pyrolytic graphite (HOPG) substrate at the solid-liquid interface, which indicates that the driving forces are attributed to the intermolecular hydrogen bonding and ?-? stacking interactions. According to the interaction mode, these organogelators are found to rapidly transform from gels to solutions by adding triethylamine.
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Primed 3D injectable microniches enabling low-dosage cell therapy for critical limb ischemia.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-02-2014
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The promise of cell therapy for repair and restoration of damaged tissues or organs relies on administration of large dose of cells whose healing benefits are still limited and sometimes irreproducible due to uncontrollable cell loss and death at lesion sites. Using a large amount of therapeutic cells increases the costs for cell processing and the risks of side effects. Optimal cell delivery strategies are therefore in urgent need to enhance the specificity, efficacy, and reproducibility of cell therapy leading to minimized cell dosage and side effects. Here, we addressed this unmet need by developing injectable 3D microscale cellular niches (microniches) based on biodegradable gelatin microcryogels (GMs). The microniches are constituted by in vitro priming human adipose-derived mesenchymal stem cells (hMSCs) seeded within GMs resulting in tissue-like ensembles with enriched extracellular matrices and enhanced cell-cell interactions. The primed 3D microniches facilitated cell protection from mechanical insults during injection and in vivo cell retention, survival, and ultimate therapeutic functions in treatment of critical limb ischemia (CLI) in mouse models compared with free cell-based therapy. In particular, 3D microniche-based therapy with 10(5) hMSCs realized better ischemic limb salvage than treatment with 10(6) free-injected hMSCs, the minimum dosage with therapeutic effects for treating CLI in literature. To the best of our knowledge, this is the first convincing demonstration of injectable and primed cell delivery strategy realizing superior therapeutic efficacy for treating CLI with the lowest cell dosage in mouse models. This study offers a widely applicable cell delivery platform technology to boost the healing power of cell regenerative therapy.
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Asymmetric Synthesis of Allylic Sulfonic Acids: Enantio- and Regioselective Iridium-Catalyzed Allylations of Na2 SO3.
Chemistry
PUBLISHED: 09-01-2014
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An enantioselective allylation reaction of allylic carbonates with sodium sulfite (Na2 SO3 ) catalyzed by Ir complex was accomplished, providing allylic sulfonic acids in good to excellent yields with a high level of enantio- and regioselectivities. (R)-2-Phenyl-2-sulfoacetic acid, a key intermediate for the synthesis of Cefsulodin and Sulbenicillin, was synthesized as well.
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Effect of rhynchophylline on conditioned place preference on expression of NR2B in methamphetamine-dependent mice.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-01-2014
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To study the effect of rhynchophylline on N-methyl d-aspartate receptor subtype 2B subunit in hippocampus of Methamphetamine-induced conditioned place preference (CPP) mice.
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Four endoplasmic reticulum resident selenoproteins may be related to the protection of selenium against cadmium toxicity in chicken lymphocytes.
Biol Trace Elem Res
PUBLISHED: 08-31-2014
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Cadmium could induce the damage of endoplasmic reticulum. In the present study, we investigated the effect of Cadmium on messenger RNA expressions of endoplasmic reticulum resident selenoproteins, selenoprotein K, selenoprotein N, selenoprotein S, and selenoprotein T, in cultured chicken lymphocytes and the antagonistic effect of Selenium. Chicken splenic lymphocytes were treated with 10(-7) mol/L Selenium, 10(-6) mol/L Cadmium, and the mixture of 10(-6) mol/L Selenium and 10(-7) mol/L Cadmium in the culture medium for 12, 24, 36, and 48 h, respectively. Then, we detected the messenger RNA expressions of selenoprotein K, selenoprotein N, selenoprotein S, and selenoprotein T by using real-time polymerase chain reaction method. The results indicated that Selenium significantly increased the expressions of selenoprotein K, selenoprotein N, selenoprotein S, and selenoprotein T, which were reduced by Cadmium in chicken splenic lymphocytes. It indicated that endoplasmic reticulum was one target of Cadmium toxication, and Cadmium toxicity might be related to the reduced expressions of selenoprotein K, selenoprotein N, selenoprotein S, and selenoprotein T in chicken lymphocytes. Selenium reserved the protective role by increasing the expressions of selenoprotein K, selenoprotein N, selenoprotein S, and selenoprotein T. The present study provided a useful clue to investigate the possible pathogenesis of Cadmium toxicity.
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Selenium deficiency mainly influences the gene expressions of antioxidative selenoproteins in chicken muscles.
Biol Trace Elem Res
PUBLISHED: 08-29-2014
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Dietary selenium (Se) deficiency induces muscular dystrophy in chicken, but the molecular mechanism remains unclear. The aim of the present study was to investigate the effect of dietary Se deficiency on the expressions of 25 selenoproteins. One-day-old broiler chickens were fed either an Se deficiency diet (0.033 mg Se/kg; produced in the Se-deficient area of Heilongjiang, China) or a diet supplemented with Se (as sodium selenite) at 0.2 mg/kg for 55 days. Then, the mRNA levels of 25 selenoproteins in chicken muscles were examined, and the principal component was further analyzed. The results showed that antioxidative selenoproteins especially Gpxs and Sepw1 were highly and extensively expressed than other types of selenoproteins in chicken muscles. In 25 selenoproteins, Gpxs, Txnrd2, Txnrd 3, Dio1, Dio 3, Selk, Sels, Sepw1, Selh, Sep15, Selu, Selpb, Sepp1, Selo, Sepx1, and SPS2 were downregulated (P??0.05). Se deficiency decreased the expressions of 19 selenoproteins (P?
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Protective effects of Salvia miltiorrhiza injection against learning and memory impairments in streptozotocin-induced diabetic rats.
Exp Ther Med
PUBLISHED: 08-19-2014
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The aim of this study was to explore the protective effects of Salvia miltiorrhiza injection against learning and memory impairment in streptozotocin (STZ)-induced diabetic rats and the possible mechanism involved. Sprague Dawley male rats (n=30) were randomized into three groups: Diabetes, diabetes treated with S. miltiorrhiza injection and normal control. Diabetes was induced by an intraperitoneal injection of STZ (65 mg/kg). The S. miltiorrhiza injection-treated rats received an intraperitoneal injection of S. miltiorrhiza (5 ml/kg/day) while the rats of the other two groups were administered an intraperitoneal injection of the same volume of 0.9% saline for four weeks. After four weeks of treatment, the escape latency and search strategies in the rats were assessed by the Morris water maze test. The protein levels of mitogen-activated protein kinase phosphatase-1 (MKP-1) were also assessed by immunohistochemistry. Four weeks after the induction of diabetes, the body weight of the diabetic rats was significantly lower and the blood glucose concentration was significantly higher than that of the control rats. S. miltiorrhiza injection was observed to improve the blood glucose and learning ability (P<0.05). Compared with the control group, the expression of MKP-1 was significantly decreased in the hippocampal area of the diabetes group; S. miltiorrhiza injection-treated rats showed an increased expression compared with the diabetic rats, but the expression remained lower than that of the normal control group (P<0.05). In conclusion, S. miltiorrhiza injection can improve the learning and memory decline of diabetic rats. The changes in expression of MKP-1 under hyperglycemia may play a role in the protective effects of S. miltiorrhiza against dementia in diabetic rats.
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BAX and CDKN1A polymorphisms correlated with clinical outcomes of gastric cancer patients treated with postoperative chemotherapy.
Med. Oncol.
PUBLISHED: 08-16-2014
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This study aims to examine the correlation between two single nucleotide polymorphisms (SNPs) of apoptosis-related genes and clinical outcomes in gastric cancer. A total of 221 patients with stage T2 and T3 gastric cancer treated with postoperative chemotherapy between 2003 and 2008 were retrospectively collected in this study to explore the association of rs4645878 located in BAX gene and rs1801270 located in CDKN1A gene with survival, recurrence, and toxicity to chemotherapy. Additionally, immunohistochemistry was used to detect the BAX expression in gastric cancer tissues. Patients carrying at least one variant genotype in BAX SNP (rs4645878) showed a significantly increased recurrence risk [hazard ratio (HR) 2.63; 95 % confidence internal (95 % CI) 1.71-4.03] and poor survival (HR 2.89; 95 % CI 1.88-4.44). Moreover, the recurrence and survival rate in patients with GA genotype was 72.7 and 24.7 %, respectively, compared with total recurrence rate of 54.8 %, P = 0.006, and compared with total survival rate of 46.6 %, P = 0.001. In addition, the GA genotype was related to lower BAX expression in gastric cancer tissues. The CDKN1A (rs1801270) mutant genotype was associated with a significantly decreased risk of hematologic toxicity [odds ratio (OR) 0.28; 95 % CI 0.12-0.63]. SNPs located in BAX and CDKN1A genes are closely associated with clinical outcomes in patients with gastric cancer.
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Prevalence and distribution of oral mucosal lesions: a cross-sectional study in Shanghai, China.
J. Oral Pathol. Med.
PUBLISHED: 08-15-2014
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An epidemiological study on the oral mucosal lesions (OMLs) in general population from China was scarce. The objective of this study was to investigate the prevalence and distribution of OMLs in Shanghai, China and to evaluate their association with demographic factors and smoking/drinking habits based on a large scaled population on a wide spectrum.
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The Pre- and Post-somatic segments of the Human Type I Spiral Ganglion Neurons - Structural and Functional Considerations Related to Cochlear Implantation.
Neuroscience
PUBLISHED: 08-13-2014
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Human auditory nerve afferents consist of two separate systems; one is represented by the large type I cells innervating the inner hair cells and the other one by the small type II cells innervating the outer hair cells. Type I spiral ganglion neurons (SGNs) constitute 96% of the afferent nerve population and, in contrast to other mammals, their soma and pre- and post-somatic segments are unmyelinated. Type II nerve soma and fibers are unmyelinated. Histopathology and clinical experience imply that human SGNs can persist electrically excitable without dendrites, thus lacking connection to the organ of Corti. The biological background to this phenomenon remains elusive. We analyzed the pre- and post-somatic segments of the type I human SGNs using immunohistochemistry and transmission electron microscopy (TEM) in normal and pathological conditions. These segments were found surrounded by non-myelinated Schwann cells (NMSC) showing strong intracellular expression of laminin-?2/collagen IV. These cells also bordered the perikaryal entry zone and disclosed surface rugosities outlined by a folded basement membrane (BM) expressing laminin-?2 and collagen IV. It is presumed that human large SGNs are demarcated by three cell categories: a) myelinated Schwann cells, b) non-myelinated Schwann cells (NMSC) and c) satellite glial cells (SGCs). Their BMs express laminin-?2/collagen IV and reaches the BM of the sensory epithelium at the habenula perforata. We speculate that the NMSC protect SGNs from further degeneration following dendrite loss. It may give further explanation why SGNs can persist as electrically excitable monopolar cells even after long time deafness, a blessing for the deaf treated with cochlear implantation.
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High-Performance Liquid-Catalyst Fuel Cell for Direct Biomass-into-Electricity Conversion.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-13-2014
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Herein, we report high-performance fuel cells that are catalyzed solely by polyoxometalate (POM) solution without any solid metal or metal oxide. The novel design of the liquid-catalyst fuel cells (LCFC) changes the traditional gas-solid-surface heterogeneous reactions to liquid-catalysis reactions. With this design, raw biomasses, such as cellulose, starch, and even grass or wood powders can be directly converted into electricity. The power densities of the fuel cell with switchgrass (dry powder) and bush allamanda (freshly collected) are 44 mW?cm(-2) and 51 mW?cm(-2) respectively. For the cellulose-based biomass fuel cell, the power density is almost 3000 times higher than that of cellulose-based microbial fuel cells. Unlike noble-metal catalysts, POMs are tolerant to most organic and inorganic contaminants. Therefore, almost any raw biomass can be used directly to produce electricity without prior purification.
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Design of an effective bifunctional catalyst organotriphosphonic acid-functionalized ferric alginate (ATMP-FA) and optimization by Box-Behnken model for biodiesel esterification synthesis of oleic acid over ATMP-FA.
Bioresour. Technol.
PUBLISHED: 08-12-2014
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Biodiesel production has become an intense research area because of rapidly depleting energy reserves and increasing petroleum prices together with environmental concerns. This paper focused on the optimization of the catalytic performance in the esterification reaction of oleic acid for biodiesel production over the bifunctional catalyst organotriphosphonic acid-functionalized ferric alginate ATMP-FA. The reaction parameters including catalyst amount, ethanol to oleic acid molar ratio and reaction temperature have been optimized by response surface methodology (RSM) using the Box-Behnken model. It was found that the reaction temperature was the most significant factor, and the best conversion ratio of oleic acid could reach 93.17% under the reaction conditions with 9.53% of catalyst amount and 8.62:1 of ethanol to oleic acid molar ratio at 91.0°C. The research results show that two catalytic species could work cooperatively to promote the esterification reaction, and the bifunctional ATMP-FA is a potential catalyst for biodiesel production.
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Functional characteristics of reversibly immortalized hepatic progenitor cells derived from mouse embryonic liver.
Cell. Physiol. Biochem.
PUBLISHED: 08-11-2014
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Liver is a vital organ and retains its regeneration capability throughout adulthood, which requires contributions from different cell populations, including liver precursors and intrahepatic stem cells. To overcome the mortality of hepatic progenitors (iHPs) in vitro, we aim to establish reversibly immortalized hepatic progenitor cells from mouse embryonic liver.
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Noble metal catalyzed aqueous phase hydrogenation and hydrodeoxygenation of lignin-derived pyrolysis oil and related model compounds.
Bioresour. Technol.
PUBLISHED: 08-11-2014
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Aqueous phase hydrodeoxygenation of lignin pyrolysis oil and related model compounds were investigated using four noble metals supported on activated carbon. The hydrodeoxygenation of guaiacol has three major reaction pathways and the demethylation reaction, mainly catalyzed by Pd, Pt and Rh, produces catechol as the products. The presence of catechol and guaiacol in the reaction is responsible for the coke formation and the catalysts deactivation. As expected, there was a significant decrease in the specific surface area of Pd, Pt and Rh catalysts during the catalytic reaction because of the coke deposition. In contrast, no catechol was produced from guaiacol when Ru was used so a completely hydrogenation was accomplished. The lignin pyrolysis oil upgrading with Pt and Ru catalysts further validated the reaction mechanism deduced from model compounds. Fully hydrogenated bio-oil was produced with Ru catalyst.
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Development of a decaaza-cyclophane stationary phase for high-performance liquid chromatography.
J Sep Sci
PUBLISHED: 08-03-2014
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A new stationary phase for high-performance liquid chromatography was prepared by covalently bonding a heteroatom-bridged cyclophane onto silica gel using 3-aminopropyltriethoxysilane as the coupling reagent. The structure of the new material was characterized by IR spectroscopy, elemental analysis and thermogravimetric analysis. The linear solvation energy relationship method was successfully employed to evaluate the new phase with a set of 25 solutes, and compared with octadecylsilyl and p-tert-butyl-calix[4]arene bonded stationary phases. The retention characteristics of the new phase are similar to the octadecylsilyl and conventional calixarene phases, and it also has distinctive features. In addition, the chromatographic behavior of the phase was illustrated by eluting alkylbenzenes and inorganic anions in the reversed phase mode and anion-exchange mode, respectively. Thus, multi-interaction mechanisms and mixed-mode separation of the new phase can very likely guarantee its promising application in the analysis of complex samples. The column has been successfully employed for the analysis of triazines in milk, and it is demonstrated to be a competitive alternative analytical method for the determination of triazine herbicide residues. This article is protected by copyright. All rights reserved.
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Pollution and skin: From epidemiological and mechanistic studies to clinical implications.
J. Dermatol. Sci.
PUBLISHED: 07-31-2014
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In recent years, the health effects associated with air pollution have been intensively studied. Most studies focus on air pollution effects on the lung and the cardiovascular system. More recently, however, epidemiological and mechanistic studies suggest that air pollution is also affecting skin integrity. This state-of-the-art review focuses on this latter aspect; it was developed with the collaboration of European and Chinese board of experts with specific interests in environmental health, clinical and basic research in dermatology and cosmetic dermatology. A literature review limited to pollution and health effects and (sensitive) skin was performed using PubMed. Review and original articles were chosen. We summarize the existing scientific evidence that air pollution exerts detrimental effects on human skin, discuss potential clinical implications and suggest specific and unspecific cosmetic protective measures.
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