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Find video protocols related to scientific articles indexed in Pubmed.
Catalytic mechanisms and regulation of protein kinases.
Meth. Enzymol.
PUBLISHED: 11-18-2014
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Protein kinases transfer a phosphoryl group from ATP onto target proteins and play a critical role in signal transduction and other cellular processes. Here, we review the kinase kinetic and chemical mechanisms and their application in understanding kinase structure and function. Aberrant kinase activity has been implicated in many human diseases, in particular cancer. We highlight applications of technologies and concepts derived from kinase mechanistic studies that have helped illuminate how kinases are regulated and contribute to pathophysiology.
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How light, temperature, and measurement and growth [CO2] interactively control isoprene emission in hybrid aspen.
J. Exp. Bot.
PUBLISHED: 11-16-2014
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Plant isoprene emissions have been modelled assuming independent controls by light, temperature and atmospheric [CO2]. However, the isoprene emission rate is ultimately controlled by the pool size of its immediate substrate, dimethylallyl diphosphate (DMADP), and isoprene synthase activity, implying that the environmental controls might interact. In addition, acclimation to growth [CO2] can shift the share of the control by DMADP pool size and isoprene synthase activity, and thereby alter the environmental sensitivity. Environmental controls of isoprene emission were studied in hybrid aspen (Populus tremula × Populus tremuloides) saplings acclimated either to ambient [CO2] of 380 ?mol mol(-1) or elevated [CO2] of 780 ?mol mol(-1). The data demonstrated strong interactive effects of environmental drivers and growth [CO2] on isoprene emissions. Light enhancement of isoprene emission was the greatest at intermediate temperatures and was greater in elevated-[CO2]-grown plants, indicating greater enhancement of the DMADP supply. The optimum temperature for isoprene emission was higher at lower light, suggesting activation of alternative DMADP sinks at higher light. In addition, [CO2] inhibition of isoprene emission was lost at a higher temperature with particularly strong effects in elevated-[CO2]-grown plants. Nevertheless, DMADP pool size was still predicted to more strongly control isoprene emission at higher temperatures in elevated-[CO2]-grown plants. We argue that interactive environmental controls and acclimation to growth [CO2] should be incorporated in future isoprene emission models at the level of DMADP pool size.
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Discovery of Pentacyclic Triterpenoids as Potential Entry Inhibitors of Influenza Viruses.
J. Med. Chem.
PUBLISHED: 11-11-2014
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Entry inhibitors are of particular importance in current efforts to develop a new generation of anti-influenza virus drugs. Here we report certain pentacyclic triterpenes exhibiting conserved structure features and with in vitro anti-influenza virus activity comparable to and even higher than that of oseltamivir. Mechanistic studies indicated that these lead triterpenoids bind tightly to the viral envelope hemagglutinin (HA), disrupting the interaction of HA with the sialic acid receptor and thus the attachment of viruses to host cells. Docking studies suggest that the binding pocket within HA for sialic acid receptor potentially acts as a targeting domain, and this is supported by structure-activity data, sialic acid competition studies and broad anti-influenza spectrum as well as less induction of drug resistance. Our study might establish the importance of triterpenoids for development of entry inhibitors of influenza viruses.
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Enhancement of visible photocatalytic performances of a Bi2MoO6-BiOCl nanocomposite with plate-on-plate heterojunction structure.
Phys Chem Chem Phys
PUBLISHED: 11-04-2014
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A visible-light-sensitive Bi2MoO6-BiOCl heterojunction photocatalyst was synthesized via a hydrothermal process. The as-prepared Bi2MoO6-BiOCl composite shows an irregular multi-plate structure with length ranging from 100 nm to 1 ?m, indicating a possibility of the plate-on-plate structure by placing Bi2MoO6 and BiOCl nanoplates over each other. The Bi2MoO6-BiOCl photocatalyst not only had a good visible-light photocatalytic performance, but also exhibited higher photocatalytic activity than pure BiOCl and Bi2MoO6. The optimal Bi2MoO6 content for the photocatalytic activity of the Bi2MoO6-BiOCl composites is 30%. Compared to pure Bi2MoO6 the photoactivity of the Bi2MoO6-BiOCl composites is almost 2.0 times higher for the RhB photodegradation, and 1.5 times higher for the phenol photodegradation under visible light irradiation. The photocatalytic mechanism was elucidated via active species trapping experiments and ESR. The ?OH and ?O2(-) played the key roles in the degradation of RhB via the Bi2MoO6-BiOCl composite. Finally, the possible charge transfer mechanism of the enhanced visible light photocatalytic activity was proposed.
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Space-Charge-Mediated Anomalous Ferroelectric Switching in P(VDF-TrEE) Polymer Films.
ACS Appl Mater Interfaces
PUBLISHED: 10-16-2014
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We report on the switching dynamics of P(VDF-TrEE) copolymer devices and the realization of additional substable ferroelectric states via modulation of the coupling between polarizations and space charges. The space-charge-limited current is revealed to be the dominant leakage mechanism in such organic ferroelectric devices, and electrostatic interactions due to space charges lead to the emergence of anomalous ferroelectric loops. The reliable control of ferroelectric switching in P(VDF-TrEE) copolymers opens doors toward engineering advanced organic memories with tailored switching characteristics.
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[A novel mutation of NTRK1 gene in a family with congenital insensitivity to pain with anhidrosis].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 10-10-2014
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To screen for mutations in the neurotrophic tyrosine kinase receptor type 1 (NTRK1) gene in a Chinese family affected with congenital insensitivity to pain with anhidrosis (CIPA).
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Effect of biochar amendment on yield and photosynthesis of peanut on two types of soils.
Environ Sci Pollut Res Int
PUBLISHED: 10-03-2014
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Biochar has significant potential to improve crop performance. This study examined the effect of biochar application on the photosynthesis and yield of peanut crop grown on two soil types. The commercial peanut cultivar Middleton was grown on red ferrosol and redoxi-hydrosol (Queensland, Australia) amended with a peanut shell biochar gradient (0, 0.375, 0.750, 1.50, 3.00 and 6.00 %, w/w, equivalent up to 85 t ha(-1)) in a glasshouse pot experiment. Biomass and pod yield, photosynthesis-[CO2] response parameters, leaf characteristics and soil properties (carbon, nitrogen (N) and nutrients) were quantified. Biochar significantly improved peanut biomass and pod yield up to 2- and 3-folds respectively in red ferrosol and redoxi-hydrosol. A modest (but significant) biochar-induced improvement of the maximum electron transport rate and saturating photosynthetic rate was observed for red ferrosol. This response was correlated to increased leaf N and accompanied with improved soil available N and biological N fixation. Biochar application also improved the availability of other soil nutrients, which appeared critical in improving peanut performance, especially on infertile redoxi-hydrosol. Our study suggests that application of peanut shell derived biochar has strong potential to improve peanut yield on red ferrosol and redoxi-hydrosol. Biochar soil amendment can affect leaf N status and photosynthesis, but the effect varied with soil type.
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[ATP-binding cassette transporters and transmembrane transport in Mycobacterium tuberculosis--a review].
Wei Sheng Wu Xue Bao
PUBLISHED: 10-03-2014
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Mycobacterium tuberculosis, an intracellular bacterium, mainly lives in the phagosome of the macrophage. It utilizes competitive uptake of nutrients as well as active efflux of noxious compounds to maintain its survival. Thus, the ATP-binding cassette transporters involved in either process mentioned above are essential for its pathogenicity. There are 38 ATP-binding cassette transporters identified in the genome of M. tuberculosis. This sort of proteins facilitate the transport of various substrates ranging from ions, sugars, amino acids, oligopeptides and drugs. In this review, we summarized the substrate specificity and transport mechanism of these transporters and their relationship with virulence in M. tuberculosis.
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A panel of microRNAs as a new biomarkers for the detection of deep vein thrombosis.
J. Thromb. Thrombolysis
PUBLISHED: 09-24-2014
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Deep vein thrombosis is one of the common complications of orthopedic surgery, and pulmonary embolism which is one of its lethal complications can lead to mortality. Numerous efforts have been made to identify reliable and predictive biomarkers to detect the early signs of deep vein thrombosis. These studies have, however, not delivered any more informative candidates than the D-dimer that have been available. Cell-free microRNAs are present in a range of body fluids and have recently been shown to be useful biomarkers in many diseases. Therefore, the purpose of present study was to identify potential microRNA biomarkers of deep vein thrombosis that are present in serum. Serum samples were taken from 18 deep vein thrombosis patients and 20 age- and sex-matched controls. TaqMan microRNA array was used for an initial screening. Real-time PCR assay was implemented to confirm the concentrations of candidate microRNAs. We found that the serum levels of miR-582, miR-195 and miR-532 of deep vein thrombosis patients were higher than those of controls. miR-582 yielded an AUC (the areas under the ROC curve) of 0.959, and the other two microRNAs yielded an AUC of 1.000 in discriminating deep vein thrombosis from controls. These data hint that serum miR-582, miR-195 and miR-532 might have potential to be a novel noninvasive biomarkers for detection of DVT. And this is the first study suggesting that serum microNRAs might be used as biomarkers for deep vein thrombosis.
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Identification and Characterization of a Methionine ?-Lyase in the Calicheamicin Biosynthetic Cluster of Micromonospora echinospora.
Chembiochem
PUBLISHED: 08-30-2014
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CalE6 is a previously uncharacterized protein involved in the biosynthesis of calicheamicins in Micromonospora echinospora. It is a pyridoxal-5'-phosphate-dependent enzyme and exhibits high sequence homology to cystathionine ?-lyases and cystathionine ?-synthases. However, it was found to be active towards methionine and to convert this amino acid into ?-ketobutyrate, ammonium, and methanethiol. The crystal structure of the cofactor-bound holoenzyme was resolved at 2.0 Å; it contains two active site residues, Gly105 and Val322, specific for methionine ?-lyases. Modeling of methionine into the active site allows identification of the active site residues responsible for substrate recognition and catalysis. These findings support that CalE6 is a putative methionine ?-lyase producing methanethiol as a building block in biosynthesis of calicheamicins.
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A preliminary assessment of the potential of using an acacia-biochar system for spent mine site rehabilitation.
Environ Sci Pollut Res Int
PUBLISHED: 08-30-2014
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Mining activities result in extensive soil degradation by removing the top soil, disturbing soil structure and altering microbial communities. Rehabilitation of spent mine sites through revegetation thus requires proper soil amendments. In this study, a pot trial was conducted to investigate the effects of a jarrah biochar on the growth and nutrient status of a native legume, Acacia tetragonophylla, grown in a mixture of topsoil and mine rejects. Two biochar application rates (37 and 74 t ha(-1)) and two types of biochar, namely nutrient-enriched and non-enriched, were tested. We measured the soil pH and electrical conductivity, the carbon (C) and nitrogen (N) contents and C and N isotope composition (?(13)C and ?(15)N) of soil and plants, the foliar phosphorus content and the growth and leaf biomass of the plants. Whilst no significant effect of biochar was observed on plant growth, biochar amendment affected soil properties and plant nutritional status. The highest rate of biochar application increased soil pH, C content and C/N ratio, and decreased soil ?(13)C. Biochar application also enhanced photosynthetic N use efficiency, as showed by the increase in foliar C/N ratio, and biological N fixation rates, as indicated by foliar ?(15)N. These positive effects were not observed when biochar was nutrient-enriched due to the associated increase in soil N. Revegetation of mine sites with acacia in combination with biochar amendment constitutes a plausible alternative to the wide use of N fertiliser through the supply of additional N to the system, even though other nutrients may be required in order to enhance plant early growth.
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A channel for 3D environmental shape in anterior inferotemporal cortex.
Neuron
PUBLISHED: 08-14-2014
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Inferotemporal cortex (IT) has long been studied as a single pathway dedicated to object vision, but connectivity analysis reveals anatomically distinct channels, through ventral superior temporal sulcus (STSv) and dorsal/ventral inferotemporal gyrus (TEd, TEv). Here, we report a major functional distinction between channels. We studied individual IT neurons in monkeys viewing stereoscopic 3D images projected on a large screen. We used adaptive stimuli to explore neural tuning for 3D abstract shapes ranging in scale and topology from small, closed, bounded objects to large, open, unbounded environments (landscape-like surfaces and cave-like interiors). In STSv, most neurons were more responsive to objects, as expected. In TEd, surprisingly, most neurons were more responsive to 3D environmental shape. Previous studies have localized environmental information to posterior cortical modules. Our results show it is also channeled through anterior IT, where extensive cross-connections between STSv and TEd could integrate object and environmental shape information.
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Investigation of bacterial and fungal diversity in tarag using high-throughput sequencing.
J. Dairy Sci.
PUBLISHED: 08-14-2014
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This is the first study on the bacterial and fungal community diversity in 17 tarag samples (naturally fermented dairy products) through a metagenomic approach involving high-throughput pyrosequencing. Our results revealed the presence of a total of 47 bacterial and 43 fungal genera in all tarag samples, in which Lactobacillus and Galactomyces were the predominant genera of bacteria and fungi, respectively. The number of some microbial genera, such as Lactococcus, Acetobacter, Saccharomyces, Trichosporon, and Kluyveromyces, among others, was found to vary between different samples. Altogether, our results showed that the microbial flora in different samples may be stratified by geographic region.
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Aberrant sonic hedgehog signaling pathway and STAT3 activation in papillary thyroid cancer.
Int J Clin Exp Med
PUBLISHED: 07-15-2014
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The sonic hedgehog (SHH) and STAT3 signaling pathways play important roles during carcinogenesis with possible interaction. To determine the association of the activation of SHH signaling pathway and STAT3 pathway in carcinogenesis of human papillary thyroid cancer (PTC), we examined the expression of SHH signaling pathway molecules including SHH, Patched (PTCH), Smoothened (SMO) and GLI1 (glioma-associated oncogene homolog 1), as well as p-STAT3 (phosphorylation at Tyr705) by immunohistochemistry in 164 cases of PTC. In PTC, 70.12%, 64.02%, 68.90%, 64.02%, and 56.71% and in the adjacent normal thyroid tissues, 18.29%, 18.90%, 26.83%, 14.63%, and 10.98% of the specimens stained positive for SHH, PTCH, SMO, GLI1, and p-STAT3, respectively. Significant difference were found for the positive rate of SHH, PTCH, SMO, and GLI1 as well as p-STAT3 expression between PTC and adjacent normal thyroid tissues. There was a high accordance rate between SHH, PTCH, SMO, and GLI1 expression and all of them positively correlated with larger tumor size, the presence of ETE and LNM, and higher TNM stage. P-STAT3 expression positively correlated with the presence of ETE and LNM, and higher TNM stage but not age, gender, tumor size of the PTC patients. Signifi cant positive correlation between p-STAT3 and SHH, PTCH, SMO and GLI expression was found in PTC. These findings suggest that the SHH and STAT3 signaling pathways are frequently activated in PTC, interact with each other and may therefore be indicators for prognosis or potential targets for therapy against PTC.
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Cascade Biocatalysis by Multienzyme-Nanoparticle Assemblies.
Bioconjug. Chem.
PUBLISHED: 07-15-2014
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Multienzyme complexes are of paramount importance in biosynthesis in cells. Yet, how sequential enzymes of cascade catalytic reactions synergize their activities through spatial organization remains elusive. Recent development of site-specific protein-nanoparticle conjugation techniques enables us to construct multienzyme assemblies using nanoparticles as the template. Sequential enzymes in menaquinone biosynthetic pathway were conjugated to CdSe-ZnS quantum dots (QDs, a nanosized particulate material) through metal-affinity driven self-assembly. The assemblies were characterized by electrophoretic methods, the catalytic activities were monitored by reverse-phase chromatography, and the composition of the multienzyme-QD assemblies was optimized through a progressive approach to achieve highly efficient catalytic conversion. Shorter enzyme-enzyme distance was discovered to facilitate intermediate transfer, and a fine control on the stoichiometric ratio of the assembly was found to be critical for the maximal synergy between the enzymes. Multienzyme-QD assemblies thereby provide an effective model to scrutinize the synergy of cascade enzymes in multienzyme complexes.
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Soil and foliar nutrient and nitrogen isotope composition (?(15)N) at 5 years after poultry litter and green waste biochar amendment in a macadamia orchard.
Environ Sci Pollut Res Int
PUBLISHED: 07-08-2014
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This study aimed to evaluate the improvement in soil fertility and plant nutrient use in a macadamia orchard following biochar application. The main objectives of this study were to assess the effects of poultry litter and green waste biochar applications on nitrogen (N) cycling using N isotope composition (?(15)N) and nutrient availability in a soil-plant system at a macadamia orchard, 5 years following application. Biochar was applied at 10 t ha(-1) dry weight but concentrated within a 3-m diameter zone when trees were planted in 2007. Soil and leaf samples were collected in 2012, and both soil and foliar N isotope composition (?(15)N) and nutrient concentrations were assessed. Both soil and foliar ?(15)N increased significantly in the poultry litter biochar plots compared to the green waste biochar and control plots. A significant relationship was observed between soil and plant ?(15)N. There was no influence of either biochars on foliar total N concentrations or soil NH4 (+)-N and NO3 (-)-N, which suggested that biochar application did not pose any restriction for plant N uptake. Plant bioavailable phosphorus (P) was significantly higher in the poultry litter biochar treatment compared to the green waste biochar treatment and control. We hypothesised that the bioavailability of N and P content of poultry litter biochar may play an important role in increasing soil and plant ?(15)N and P concentrations. Biochar application affected soil-plant N cycling and there is potential to use soil and plant ?(15)N to investigate N cycling in a soil-biochar-tree crop system. The poultry litter biochar significantly increased soil fertility compared to the green waste biochar at 5 years following biochar application which makes the poultry litter a better feedstock to produce biochar compared to green waste for the tree crops.
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[Characteristics and influencing factors of HIV detection among HIV/AIDS patients in Zhejiang province in 2012].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 07-03-2014
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To assess the characteristics and influencing factors of HIV detection among HIV/AIDS patients in Zhejiang province.
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Gefitinib, an EGFR tyrosine kinase inhibitor, activates autophagy through AMPK in human lung cancer cells.
J BUON
PUBLISHED: 06-27-2014
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To investigate the effects of autophagy on growth inhibition by gefitinib in non-small cell lung cancer (NSCLC) cell lines and its probable mechanism.
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How IGF-1 activates its receptor.
Elife
PUBLISHED: 06-23-2014
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The type I insulin-like growth factor receptor (IGF1R) is involved in growth and survival of normal and neoplastic cells. A ligand-dependent conformational change is thought to regulate IGF1R activity, but the nature of this change is unclear. We point out an underappreciated dimer in the crystal structure of the related Insulin Receptor (IR) with Insulin bound that allows direct comparison with unliganded IR and suggests a mechanism by which ligand regulates IR/IGF1R activity. We test this mechanism in a series of biochemical and biophysical assays and find the IGF1R ectodomain maintains an autoinhibited state in which the TMs are held apart. Ligand binding releases this constraint, allowing TM association and unleashing an intrinsic propensity of the intracellular regions to autophosphorylate. Enzymatic studies of full-length and kinase-containing fragments show phosphorylated IGF1R is fully active independent of ligand and the extracellular-TM regions. The key step triggered by ligand binding is thus autophosphorylation.
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Assessment of the bacterial and fungal diversity in home-made yoghurts of Xinjiang, China by pyrosequencing.
J. Sci. Food Agric.
PUBLISHED: 06-15-2014
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The aim of this study was to gain a deeper knowledge of the bacterial and fungal community diversity in local home-made yoghurts from Zhaosu and Tekesi counties, Xinjiang, China, where a relatively high proportion of the ethnic minority population resides.
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Ligand-dependent active-site closure revealed in the crystal structure of Mycobacterium tuberculosis MenB complexed with product analogues.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 06-14-2014
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1,4-Dihydroxy-2-naphthoyl coenzyme A (DHNA-CoA) synthase catalyzes an essential intramolecular Claisen condensation in menaquinone biosynthesis and is an important target for the development of new antibiotics. This enzyme in Mycobacterium tuberculosis is cofactor-free and is classified as a type II DHNA-CoA synthase, differing from type I enzymes, which rely on exogenous bicarbonate for catalysis. Its crystal structures in complex with product analogues have been determined at high resolution to reveal ligand-dependent structural changes, which include the ordering of a 27-residue active-site loop (amino acids 107-133) and the reorientation of the carboxy-terminal helix (amino acids 289-301) that forms part of the active site from the opposing subunit across the trimer-trimer interface. These structural changes result in closure of the active site to the bulk solution, which is likely to take place through an induced-fit mechanism, similar to that observed for type I DHNA-CoA synthases. These findings demonstrate that the ligand-dependent conformational changes are a conserved feature of all DHNA-CoA synthases, providing new insights into the catalytic mechanism of this essential tubercular enzyme.
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Enhanced extraordinary optical transmission (EOT) through arrays of bridged nanohole pairs and their sensing applications.
Nanoscale
PUBLISHED: 06-06-2014
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Extraordinary optical transmission (EOT) through arrays of gold nanoholes was studied with light across the visible to the near-infrared spectrum. The EOT effect was found to be improved by bridging pairs of nanoholes due to the concentration of the electromagnetic field in the slit between the holes. The geometrical shape and separation of the holes in these pairs of nanoholes affected the intensity of the transmission and the wavelength of resonance. Changing the geometrical shapes of these nanohole pairs from triangles to circles to squares leads to increased transmission intensity as well as red-shifting resonance wavelengths. The performance of bridged nanohole pairs as a plasmonic sensor was investigated. The bridged nanohole pairs were able to distinguish methanol, olive oil and microscope immersion oil for the different surface plasmon resonance in transmission spectra. Numerical simulation results were in agreement with experimental observations.
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The role of the hepatocyte growth factor/c-MET pathway in pancreatic stellate cell-endothelial cell interactions: antiangiogenic implications in pancreatic cancer.
Carcinogenesis
PUBLISHED: 05-29-2014
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Activated cancer-associated human pancreatic stellate cells (CAhPSCs, which produce the collagenous stroma of pancreatic cancer [PC]) are known to play a major role in PC progression. Apart from inducing cancer cell proliferation and migration, CAhPSCs have also been implicated in neoangiogenesis in PC. However, the mechanisms mediating the observed angiogenic effects of CAhPSCs are unknown. A candidate pathway that may be involved in this process is the hepatocyte growth factor (HGF)/c-MET pathway and its helper molecule, urokinase-type plasminogen activator (uPA). This study investigated the effects of CAhPSC secretions on endothelial cell function in the presence and absence of HGF, c-MET and uPA inhibitors. HGF levels in CAhPSC secretions were quantified using ELISA. CAhPSC secretions were then incubated with human microvascular endothelial cells (HMEC-1) and angiogenesis assessed by quantifying HMEC-1 tube formation and proliferation. CAhPSC-secreted HGF significantly increased HMEC-1 tube formation and proliferation; notably, these effects were downregulated by inhibition of HGF, its receptor c-MET and uPA. Phosphorylation of p38 mitogen-activated protein kinase was downregulated during inhibition of the HGF/c-MET pathway, whereas phosphatidylinositol-3 kinase and ERK1/2 remained unaffected. Our studies have shown for the first time that CAhPSCs induce proliferation and tube formation of HMEC-1 and that the HGF/c-MET pathway plays a major role in this induction. Given that standard antiangiogenic treatment targeting vascular endothelial growth factor has had limited success in the clinical setting, the findings of the current study provide strong support for a novel, alternative antiangiogenic approach targeting the HGF/c-MET and uPA pathways in PC.
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Grape seed extract supplementation attenuates the heat stress-induced responses of jejunum epithelial cells in Simmental × Qinchuan steers.
Br. J. Nutr.
PUBLISHED: 05-20-2014
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Grape seed extract (GSE), a rich source of polyphenols, is reported to possess antioxidant, anti-inflammatory and immunomodulatory properties. The objective of the present study was to determine whether GSE could attenuate the heat stress-induced responses of jejunum epithelial cells (JEC) in cattle. The JEC of a steer (Simmental × Qinchuan) were exposed to heat stress for 2 h in the absence (0 ?g/ml) or presence (10, 20, 40 and 80 ?g/ml) of GSE in the culture medium. When cultured at 40°C, JEC supplemented with GSE exhibited increased glutathione peroxidase activity (P= 0·04), viability (P= 0·004), and mRNA expression of epidermal growth factor (EGF; P= 0·03) and EGF receptor (EGFR; P = 0·01). Under the same conditions, the cells exhibited decreased mRNA expression of IL-8 (P= 0·01) and TNF-? (P= 0·03) and decreased protein concentrations of IL-1? (P= 0·02), Toll-like receptor 4 (TLR4; P= 0·04) and heat shock protein 70 (HSP70; P< 0·001). When cultured at 43°C, JEC supplemented with GSE exhibited increased catalase activity (P= 0·04), viability (P< 0·001), and mRNA expression of EGF (P< 0·001) and EGFR (P< 0·001) and decreased protein concentrations of IL-1? (P< 0·001), TLR4 (P= 0·03) and HSP70 (P< 0·001), as well as mRNA expression of IL-8 (P< 0·001), TLR4 (P= 0·002) and TNF-? (P< 0·001). Temperature × GSE concentration interactions were also observed for the concentrations of IL-1? (P< 0·001), IL-8 (P< 0·001), TNF-? (P= 0·01) and HSP70 (P= 0·04) and viability (P< 0·001) of JEC. The results of the present study indicate that GSE can attenuate the responses of JEC induced by heat stress within a certain range of temperatures.
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Scanning laser-line source technique for nondestructive evaluation of cracks in human teeth.
Appl Opt
PUBLISHED: 05-03-2014
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This paper describes the first application of a remote nondestructive laser ultrasonic (LU) system for clinical diagnosis of cracks in human teeth, to our knowledge. It performs non-contact cracks detection on small-dimension teeth samples. Two extracted teeth with different types of cracks (cracked tooth and craze lines), which have different crack depths, are used as experimental samples. A series of ultrasonic waves were generated by a scanning laser-line source technique and detected with a laser-Doppler vibrometer on the two samples. The B-scan images and peak-to-peak amplitude variation curves of surface acoustic waves were obtained for evaluating the cracks' position and depth. The simulation results calculated by finite element method were combined with the experimental results for accurately measuring the depth of crack. The results demonstrate that this LU system has been successfully applied on crack evaluation of human teeth. And as a remote, nondestructive technique, it has great potential for early in vivo diagnosis of cracked tooth and even the future clinical dental tests.
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Is density of neighbourhood restaurants associated with BMI in rural Chinese adults? A longitudinal study from the China Health and Nutrition Survey.
BMJ Open
PUBLISHED: 04-24-2014
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The neighbourhood availability of restaurants has been linked to the weight status. However, little is known regarding the relation between access to restaurant and obesity among the Chinese population. This study aims to explore the relationship between neighbourhood restaurant density and body mass index (BMI) in rural China.
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Extraordinary mid-infrared transmission of subwavelength holes in gold films.
J Nanosci Nanotechnol
PUBLISHED: 04-17-2014
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Gold (Au) nanoholes are fabricated with electron-beam lithography and used for the investigation of extraordinary transmission in mid-infrared regime. Transmission properties of the nanoholes are studied as the dependence on hole-size. Transmittance spectra are characterized by Fourier transform infrared spectroscopy (FTIR) and enhanced transmittance through the subwavelength holes is observed. The transmission spectra exhibit well-defined maximum and minimum of which the position are determined by the lattice of the hole array. The hole-size primarily influence the transmission intensity and bandwidth of the resonance peak. With an increase of hole-size, while keep lattice constant fixed, the intensity of the resonance peak and the bandwidth increases, which are due to the localized surface plasmons. Numerical simulation for the transmission through the subwavelength holes is performed and the simulated results agree with the experimental observations.
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Molecular basis of the general base catalysis of an ?/?-hydrolase catalytic triad.
J. Biol. Chem.
PUBLISHED: 04-15-2014
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The serine-histidine-aspartate triad is well known for its covalent, nucleophilic catalysis in a diverse array of enzymatic transformations. Here we show that its nucleophilicity is shielded and its catalytic role is limited to being a specific general base by an open-closed conformational change in the catalysis of (1R,6R)-2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase (or MenH), a typical ?/?-hydrolase fold enzyme in the vitamin K biosynthetic pathway. This enzyme is found to adopt an open conformation without a functional triad in its ligand-free form and a closed conformation with a fully functional catalytic triad in the presence of its reaction product. The open-to-closed conformational transition involves movement of half of the ?-helical cap domain, which causes extensive structural changes in the ?/?-domain and forces the side chain of the triad histidine to adopt an energetically disfavored gauche conformation to form the functional triad. NMR analysis shows that the inactive open conformation without a triad prevails in ligand-free solution and is converted to the closed conformation with a properly formed triad by the reaction product. Mutation of the residues crucial to this open-closed transition either greatly decreases or completely eliminates the enzyme activity, supporting an important catalytic role for the structural change. These findings suggest that the open-closed conformational change tightly couples formation of the catalytic triad to substrate binding to enhance the substrate specificities and simultaneously shield the nucleophilicity of the triad, thus allowing it to expand its catalytic power beyond the nucleophilic catalysis.
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Improving causality induction with category learning.
ScientificWorldJournal
PUBLISHED: 04-07-2014
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Causal relations are of fundamental importance for human perception and reasoning. According to the nature of causality, causality has explicit and implicit forms. In the case of explicit form, causal-effect relations exist at either clausal or discourse levels. The implicit causal-effect relations heavily rely on empirical analysis and evidence accumulation. This paper proposes a comprehensive causality extraction system (CL-CIS) integrated with the means of category-learning. CL-CIS considers cause-effect relations in both explicit and implicit forms and especially practices the relation between category and causality in computation. In elaborately designed experiments, CL-CIS is evaluated together with general causality analysis system (GCAS) and general causality analysis system with learning (GCAS-L), and it testified to its own capability and performance in construction of cause-effect relations. This paper confirms the expectation that the precision and coverage of causality induction can be remarkably improved by means of causal and category learning.
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Comparison of venous thromboembolism after total hip arthroplasty between ankylosing spondylitis and osteoarthritis.
Biomed Res Int
PUBLISHED: 04-01-2014
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Ankylosing spondylitis (AS), an inflammatory rheumatic disease, will gradually lead to severe hip joint dysfunction. Total hip arthroplasty is a useful method to improve patients' quality of life. The aim of this study was to compare the incidence and risk factors of deep vein thrombosis (DVT) between AS and hip osteoarthritis.
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Mechanisms of immune injury and heterogeneity of bone marrow hematopoietic cells island in patients with auto-immuno-related hematocytopenia.
J Immunoassay Immunochem
PUBLISHED: 03-27-2014
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Because of environmental pollution more and more people are suffered with auto-immuno-related hematocytopenia (AIRH). Serum IL-12, IL-17, and IFN-? levels were detected by ELISA and lymphocyte subsets were analyzed by flow cytometry. Peroxidase (POX) and HLA-DR of immune cells were detected by cytochemical and immunochemical staining. Cells expressing anti-human IgG, Fc?R II, MR, and other molecules in HI were detected by immunofluorescence. Serum IL-12, IL-17, and IFN-? levels of patients were significantly higher than control group. Lymphocyte subsets of patients showed that the percentages of CD19+ B cells and CD3+ CD8+ T cell in peripheral blood were both significantly elevated. HI were mainly classified into three types, in these three types of hematopoietic cells island, peroxidase, and HLA-DR expression varied. Hematopoietic cells with pathological changes expressed anti-human IgG. The immunocytes with different levels of immunomolecules adhered captured and devoured abnormal hematopoietic cells. Immune cells expressed IL-12, IL-17A, and IL-17RA, leading to inflammatory injury of hematopoietic cells. HI destroys cells which connect auto-antibodies. Immune cells in HI express a variety of immune molecules, promote cell immune responses, and amplify the inflammatory reaction by ADCC effect or phagocytosis. These ultimately destruct directly and damage indirectly hematopoietic cells.
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Diagnostic Value of Ultrasound-detected Calcification in Thyroid Nodules.
Ann. Acad. Med. Singap.
PUBLISHED: 03-22-2014
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Introduction: This study analyses the diagnostic value of ultrasonography (US) detection for calcification in thyroid nodules. Materials and Methods: We analysed the preoperative US findings and clinical characteristics of 577 malignant and 3434 benign thyroid patients who underwent surgery in our hospital. Results: The malignant rate in patients with microcalcification hyperechoic and tiny calcification foci ?2 mm in diameter was significantly higher than the non-calcification and other calcification group (P <0.001). The malignant rate in single calcifi cation nodule was signifi cantly higher than that in multiple nodule group (P <0.01). Most of the patients (37/39) with lymph node calcification were malignant. The malignant rate of calcification and microcalcification was significantly higher in patients <45 years old than in older patients (P <0.05). Conclusion: Compared with other calcifications, microcalcification should be a better predictor of thyroid carcinoma. Malignancy should be highly suspected in patients with single calcification nodule, especially with lymph node calcification. Patients younger than 45 years of age with calcification or microcalcification have a greater risk for thyroid carcinoma.
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Targeting histone deacetylases (HDACs) and Wee1 for treating high-risk neuroblastoma.
Pediatr Blood Cancer
PUBLISHED: 03-20-2014
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Despite advances in treatment regimens, patients with high-risk neuroblastoma have long-term survival rates of
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P-selectin: an unpredicted factor for deep vein thrombosis after total hip arthroplasty.
Biomed Res Int
PUBLISHED: 03-20-2014
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Deep vein thrombosis (DVT) is a severe complication after total hip arthroplasty (THA). It leads to acute pulmonary embolism, a life-threatening disease. P-selectin is a 140-kDa transmembrane glycoprotein. Elevated P-selectin was associated with 1.7-fold increase in the risk of venous thrombosis.
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A fully integrated isoprenoid emissions model coupling emissions to photosynthetic characteristics.
Plant Cell Environ.
PUBLISHED: 03-14-2014
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The lack of a mechanistic basis has hampered modelling isoprene emission responses to environmental drivers, in particular the simulation of isoprene emissions under different CO? concentrations. Here, we advance previous semi-mechanistic model formulations by introducing a model that explicitly links electron availability for other purpose than carbon assimilation (or available energy for secondary metabolism processes; supply-constraint) and enzyme activity (capacity-constraint) to emissions. We furthermore investigate the sensitivity of the model to variations in photosynthetic and emission-specific parameters. By comparing species-specific simulations with experimental data, we demonstrate that differences in photosynthetic characteristics can explain inter-species differences in emissions. Interestingly, the seasonal development of emissions could also be explained to some degree by the change in energy supply from photosynthesis throughout the season. In addition, we show that the principal responses are not limited to isoprene but can be formulated to describe the emission of other light-dependent volatile species. The proposed model is suitable for implementation into regional and global models, particularly those that already provide species-specific photosynthesis estimates.
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454 pyrosequencing reveals changes in the faecal microbiota of adults consuming Lactobacillus casei Zhang.
FEMS Microbiol. Ecol.
PUBLISHED: 03-09-2014
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Probiotics are believed to help to maintain a healthy balance of the human gut microbiota. Lactobacillus casei Zhang (LcZ) is a novel potential probiotic isolated from the naturally fermented food koumiss. To better understand the impact of this potential probiotic on human intestinal microbiota, 24 subjects were randomly recruited for a longitudinal study: the subjects were required to consume LcZ for 28 days, and faecal samples were collected prior to, during and after the LcZ consumption phase. Alterations in the gut microbiota were monitored using 454 pyrosequencing and quantitative polymerase chain reaction(q-PCR) technologies. We found that the consumption of LcZ significantly altered the composition of intestinal microbiota (P < 0.001) and the gut microbiota diversity. Further analysis at the genus level revealed a positive correlation between LcZ and Prevotella, Lactobacillus, Faecalibacterium, Propionibacterium, Bifidobacterium and an unidentified genus from Bacteroidaceae and Lachnospiraceae and a negative correlation between LcZ administration and the presence of Clostridium, Phascolarctobacterium, Serratia, Enterococcus, Shigella and Shewanella. Furthermore, these changes were confirmed by q-PCR data.
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Association of a single nucleotide polymorphism in HOXB9 with developmental dysplasia of the hip: a case-control study.
J. Orthop. Res.
PUBLISHED: 03-07-2014
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Developmental dysplasia of the hip (DDH) is one of the most common skeletal disorders. It comprises a spectrum of abnormalities, including shallow acetabulum and decreased coverage of the femoral head. Genetic component plays a considerable role in the aetiology of DDH. HOXB9 may be involved in the aetiology and pathogenesis of DDH, as it plays an important role in the development of the limbs. Our objective was to evaluate whether single nucleotide polymorphisms (SNPs) of HOXB9 (rs2303486 and rs8844) were associated with DDH in Chinese population. The HOXB9 tag SNPs were genotyped in 460 DDH cases and 562 control subjects by Taqman assay, and their association was examined. rs8844 was not associated with DDH. rs2303486 was associated with DDH in the dominant genetic model (p = 0.037; odds ratio (OR) = 1.32; 95% confidence interval (CI) = 1.02–1.71). After stratification by sex, significant association of the dominant genetic model still existed in the female subjects (p = 0.015; OR = 1.46; 95% CI = 1.08–1.98),but not in the male subjects. After stratification by severity, we discovered an association with hip dislocation in the dominant model(p=0.042; OR = 1.35; 95% CI = 1.01–1.80), but not with subluxation or instability. HOXB9 is associated with DDH in Chinese.
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Efficacy of metformin-based oral antidiabetic drugs is not inferior to insulin glargine in newly diagnosed type 2 diabetic patients with severe hyperglycemia after short-term intensive insulin therapy.
J Diabetes
PUBLISHED: 03-05-2014
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Insulin therapy should be strongly considered in newly diagnosed type 2 diabetic (T2D) patients with severe hyperglycemia. However, whether insulin be continued or patients switched to an oral antidiabetic drug (OAD) after short-term intensive insulin therapy (ITT) is not clear.
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The effect of thick fibers and large pores of electrospun poly(?-caprolactone) vascular grafts on macrophage polarization and arterial regeneration.
Biomaterials
PUBLISHED: 03-01-2014
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The vascular grafts prepared by electrospinning often have relatively small pores, which limit cell infiltration into the grafts and hinder the regeneration and remodeling of the grafts into neoarteries. To overcome this problem, macroporous electrospun polycaprolactone (PCL) scaffolds with thicker fibers (5-6 ?m) and larger pores (?30 ?m) were fabricated in the present study. In vitro cell culture indicated that macrophages cultured on thicker-fiber scaffolds tended to polarize into the immunomodulatory and tissue remodeling (M2) phenotype, while those cultured on thinner-fiber scaffolds expressed proinflammatory (M1) phenotype. In vivo implantation by replacing rat abdominal aorta was performed and followed up for 7, 14, 28 and 100 d. The results demonstrated that the macroporous grafts markedly enhanced cell infiltration and extracellular matrix (ECM) secretion. All grafts showed satisfactory patency for up to 100 days. At day 100, the endothelium coverage was complete, and the regenerated smooth muscle layer was correctly organized with abundant ECM similar to those in the native arteries. More importantly, the regenerated arteries demonstrated contractile response to adrenaline and acetylcholine-induced relaxation. Analysis of the cellularization process revealed that the thicker-fiber scaffolds induced a large number of M2 macrophages to infiltrate into the graft wall. These macrophages further promoted cellular infiltration and vascularization. In conclusion, the present study confirmed that the scaffold structure can regulate macrophage phenotype. Our thicker-fiber electrospun PCL vascular grafts could enhance the vascular regeneration and remodeling process by mediating macrophage polarization into M2 phenotype, suggesting that our constructs may be a promising cell-free vascular graft candidate and are worthy for further in vivo evaluation.
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Facile fabrication of nanoporous PdFe alloy for nonenzymatic electrochemical sensing of hydrogen peroxide and glucose.
Anal. Chim. Acta
PUBLISHED: 02-28-2014
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Nanoporous (NP) PdFe alloy is easily fabricated through one step mild dealloying of PdFeAl ternary source alloy in NaOH solution. Electron microscopy characterization demonstrates that selectively dissolving Al from PdFeAl alloy generates three-dimensional bicontinuous nanospongy architecture with the typical ligament size around 5 nm. Electrochemical measurements show that the NP-PdFe alloy exhibits the superior electrocatalytic activity and durability towards hydrogen peroxide (H2O2) detection compared with NP-Pd and commercial Pd/C catalysts. In addition, NP-PdFe performs high sensing performance towards H2O2 in a wide linear range from 0.5 to 6 mM with a low detection limit of 2.1 ?M. This nanoporous structure also can sensitively detect glucose over a wide concentration range (1-32 mM) with a low detection limit of 1.6 ?M and high resistance against chloride ions. Along with these attractive features, the as-made NP-PdFe alloy also has a good anti-interference towards ascorbic acid, uric acid, and dopamine.
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Incidence of symptomatic and asymptomatic venous thromboembolism after elective knee arthroscopic surgery: a retrospective study with routinely applied venography.
Arthroscopy
PUBLISHED: 02-26-2014
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The purpose of this study was to assess the incidence of total venous thromboembolism (VTE) after knee arthroscopy with routinely applied venography.
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Effect of sustained heparin release from PCL/chitosan hybrid small-diameter vascular grafts on anti-thrombogenic property and endothelialization.
Acta Biomater
PUBLISHED: 02-19-2014
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Thrombus formation and subsequent occlusion are the main reasons for the failure of small-diameter vascular grafts. In this study, a hybrid small-diameter vascular graft was developed from synthetic polymer poly(?-caprolactone) (PCL) and natural polymer chitosan (CS) by the co-electrospinning technique. Heparin was immobilized on the grafts through ionic bonding between heparin and CS fibers. The immobilization was relatively stable, and heparin could continuously release from the grafts for more than 1month. Heparin functionalization evidently improved the hemocompatibility of the PCL/CS vascular grafts, which was illustrated by the reduced platelet adhesion and prolonged coagulation time (activated partial thromboplastin time, prothrombin time and thromboplastin time) as shown in the human plasma assay, and was further confirmed by the ex vivo arteriovenous shunt experiment. In vitro cell proliferation assay showed that heparin can promote the growth of human umbilical vein endothelial cells, while moderately inhibiting the proliferation of vascular smooth muscle cells, a main factor for neointimal hyperplasia. Implantation in rat abdominal aorta was performed for 1month. Results indicate that sustained release of heparin provided optimal anti-thrombogenic effect by reducing thrombus formation and maintaining the patency. Furthermore, heparin functionalization also enhanced in situ endothelialization, thereby preventing the occurrence of restenosis. In conclusion, it provides a facile and useful technique for the development of heparinized medical devices, including vascular grafts.
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Pancreatic cancer and its stroma: a conspiracy theory.
World J. Gastroenterol.
PUBLISHED: 02-18-2014
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Pancreatic cancer is characterised by a prominent desmoplastic/stromal reaction that has received little attention until recent times. Given that treatments focusing on pancreatic cancer cells alone have failed to significantly improve patient outcome over many decades, research efforts have now moved to understanding the pathophysiology of the stromal reaction and its role in cancer progression. In this regard, our Group was the first to identify the cells (pancreatic stellate cells, PSCs) that produced the collagenous stroma of pancreatic cancer and to demonstrate that these cells interacted closely with cancer cells to facilitate local tumour growth and distant metastasis. Evidence is accumulating to indicate that stromal PSCs may also mediate angiogenesis, immune evasion and the well known resistance of pancreatic cancer to chemotherapy and radiotherapy. This review will summarise current knowledge regarding the critical role of pancreatic stellate cells and the stroma in pancreatic cancer biology and the therapeutic approaches being developed to target the stroma in a bid to improve the outcome of this devastating disease.
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Preoperative diagnosis and intraoperative protection of nonrecurrent laryngeal nerve: a review of 5 cases.
Med. Sci. Monit.
PUBLISHED: 02-13-2014
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Nonrecurrent laryngeal nerve (NRLN) is a risk factor for nerve injury during thyroidectomy or parathyroidectomy. It is usually associated with abnormal vasculature that can be identified by several imaging methods. The aim of this study was to retrospectively analyze the preoperative diagnosis and intraoperative protection of NRLN.
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A model of plant isoprene emission based on available reducing power captures responses to atmospheric CO?.
New Phytol.
PUBLISHED: 02-11-2014
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We present a unifying model for isoprene emission by photosynthesizing leaves based on the hypothesis that isoprene biosynthesis depends on a balance between the supply of photosynthetic reducing power and the demands of carbon fixation. We compared the predictions from our model, as well as from two other widely used models, with measurements of isoprene emission from leaves of Populus nigra and hybrid aspen (Populus tremula × P. tremuloides) in response to changes in leaf internal CO2 concentration (C(i)) and photosynthetic photon flux density (PPFD) under diverse ambient CO2 concentrations (C(a)). Our model reproduces the observed changes in isoprene emissions with C(i) and PPFD, and also reproduces the tendency for the fraction of fixed carbon allocated to isoprene to increase with increasing PPFD. It also provides a simple mechanism for the previously unexplained decrease in the quantum efficiency of isoprene emission with increasing C(a). Experimental and modelled results support our hypothesis. Our model can reproduce the key features of the observations and has the potential to improve process-based modelling of isoprene emissions by land vegetation at the ecosystem and global scales.
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Association of single nucleotide polymorphisms in estrogen receptor alpha gene with susceptibility to knee osteoarthritis: a case-control study in a Chinese Han population.
Biomed Res Int
PUBLISHED: 02-07-2014
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Osteoarthritis (OA) is the most prevalent form of arthritis and its multifactorial nature has been increasingly recognized. Genetic factors play an important role in OA etiology and estrogen receptor alpha (ESR1) gene polymorphisms may be involved. This study tried to explore whether the ESR1 gene single nucleotide polymorphisms (SNPs) were associated with primary knee OA in the Chinese Han population. Two SNPs, rs2234693 and rs9340799, were genotyped in 469 cases and 522 controls. Rs2234693 was associated with knee OA in the dominant genetic model (TT + TC versus CC) (P = 0.025) and a higher T allele frequency existed (P = 0.047) among females. The combined genotype (TT + TC) (P = 0.025) and T allele (P = 0.016) were related with mild knee OA only. For rs9340799, A allele was associated with knee OA in all subjects (P = 0.031) and females (P = 0.046). Statistical differences were detected in the dominant genetic model (AA + AG versus GG) among females (P = 0.030). The combined genotype (AA + AG) (P = 0.036) and A allele (P = 0.039) were merely correlated with mild knee OA. ESR1 gene is considerably associated with knee OA etiology in the Chinese Han population.
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A replication study for the association of rs726252 in PAPPA2 with developmental dysplasia of the hip in Chinese Han population.
Biomed Res Int
PUBLISHED: 02-03-2014
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Developmental dysplasia of the hip (DDH) is a common developmental hip disorder, which ranges from mild acetabulum malformation to irreducible hip dislocation. A previous study suggested a significant association of pregnancy-associated plasma protein-A2 (PAPPA2) with DDH susceptibility in Chinese Han population. But with the consideration of the sample size, the association was still debatable. To confirm the association of the reported single nucleotide polymorphism (SNP) in PAPPA2, rs726252 with DDH, we conducted a case-control study in a larger number of subjects. We genotyped rs726252 in 697 DDH subjects and 707 control subjects by TaqMan assay. The association between this SNP and DDH was evaluated statistically. No significant difference was found in any comparison of genotype distribution nor allele frequency between cases and controls. Our replication study indicated that the association between rs726252 and DDH in Chinese Han population was debatable. The association between PAPPA2 and DDH should be evaluated by additional studies.
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Losartan-induced hypotension leads to tau hyperphosphorylation and memory deficit.
J. Alzheimers Dis.
PUBLISHED: 01-23-2014
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Recent studies have reported a correlation between dementia and low blood pressure. How hypotension is associated with the increased risk of Alzheimer's disease (AD) remains unclear. Here we show that one month treatment of losartan, an angiotensin II type 1 (AT1) receptor antagonist, causes chronic and sustained hypotension, along with oxidative stress in adult male Sprague-Dawley rats. Furthermore, we show that losartan treatment increases the level of inactivated protein phosphatase 2A (PP2A) and the hyperphosphorylation of tau at Ser 199 and Ser 396. Rats treated with losartan present memory deficits and decreases in spine-density. These findings suggest that losartan-induced hypotension may increase the risk of AD-like pathological alteration and behavioral impairment through oxidative stress which leads to tau hyperphosphorylation and loss of dendritic spines.
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A novel multi-locus sequence typing (MLST) protocol for Leuconostoc lactis isolates from traditional dairy products in China and Mongolia.
BMC Microbiol.
PUBLISHED: 01-17-2014
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Economically, Leuconostoc lactis is one of the most important species in the genus Leuconostoc. It plays an important role in the food industry including the production of dextrans and bacteriocins. Currently, traditional molecular typing approaches for characterisation of this species at the isolate level are either unavailable or are not sufficiently reliable for practical use. Multilocus sequence typing (MLST) is a robust and reliable method for characterising bacterial and fungal species at the molecular level. In this study, a novel MLST protocol was developed for 50 L. lactis isolates from Mongolia and China.
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Multilocus sequence typing of Lactococcus lactis from naturally fermented milk foods in ethnic minority areas of China.
J. Dairy Sci.
PUBLISHED: 01-17-2014
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To determine the genetic diversity and phylogenetic relationships among Lactococcus lactis isolates, 197 strains isolated from naturally homemade yogurt in 9 ethnic minority areas of 6 provinces of China were subjected to multilocus sequence typing (MLST). The MLST analysis was performed using internal fragment sequences of 12 housekeeping genes (carB, clpX, dnaA, groEL, murC, murE, pepN, pepX, pyrG, recA, rpoB, and pheS). Six (dnaA) to 8 (murC) different alleles were detected for these genes, which ranged from 33.62 (clpX) to 41.95% (recA) GC (guanine-cytosine) content. The nucleotide diversity (?) ranged from 0.00362 (murE) to 0.08439 (carB). Despite this limited allelic diversity, the allele combinations of each strain revealed 72 different sequence types, which denoted significant genotypic diversity. The dN/dS ratios (where dS is the number of synonymous substitutions per synonymous site, and dN is the number of nonsynonymous substitutions per nonsynonymous site) were lower than 1, suggesting potential negative selection for these genes. The standardized index of association of the alleles IA(S)=0.3038 supported the clonality of Lc. lactis, but the presence of network structure revealed by the split decomposition analysis of the concatenated sequence was strong evidence for intraspecies recombination. Therefore, this suggests that recombination contributed to the evolution of Lc. lactis. A minimum spanning tree analysis of the 197 isolates identified 14 clonal complexes and 23 singletons. Phylogenetic trees were constructed based on the sequence types, using the minimum evolution algorithm, and on the concatenated sequence (6,192 bp), using the unweighted pair-group method with arithmetic mean, and these trees indicated that the evolution of our Lc. lactis population was correlated with geographic origin. Taken together, our results demonstrated that MLST could provide a better understanding of Lc. lactis genome evolution, as well as useful information for future studies on global Lc. lactis structure and genetic evolution, which will lay the foundation for screening Lc. lactis as starter cultures in fermented dairy products.
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A new phytophagous eulophid wasp (Hymenoptera: Chalcidoidea: Eulophidae) that feeds within leaf buds and cones of Pinus massoniana.
Zootaxa
PUBLISHED: 01-07-2014
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Aprostocetus pinus sp. nov. (Chalcidoidea: Eulophidae) is newly described as a leaf bud and microstrobilus pest of Pinus massoniana (Pinales: Pinaceae), an important afforestation species in southeast China. Both sexes of the parasitoid are described and illustrated. 
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Investment in plant research and development bears fruit in China.
Plant Cell Rep.
PUBLISHED: 01-06-2014
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Recent rapid progress in plant science and biotechnology in China demonstrates that China's stronger support for funding in plant research and development (R&D) has borne fruit. Chinese groups have contributed major advances in a range of fields, such as rice biology, plant hormone and developmental biology, genomics and evolution, plant genetics and epigenetics, as well as plant biotechnology. Strigolactone studies including those identifying its receptor and dissecting its complex structure and signaling are representative of the recent researches from China at the forefront of the field. These advances are attributable in large part to interdisciplinary studies among scientists from plant science, chemistry, bioinformatics, structural biology, and agronomy. The platforms provided by national facilities facilitate this collaboration. As well, efficient restructuring of the top-down organization of state programs and free exploration of scientists' interests have accelerated achievements by Chinese researchers. Here, we provide a general outline of China's progress in plant R&D to highlight fields in which Chinese research has made significant contributions.
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The Protective Effect of Esculentoside A on Experimental Acute Liver Injury in Mice.
PLoS ONE
PUBLISHED: 01-01-2014
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Inflammatory response and oxidative stress are considered to play an important role in the development of acute liver injury induced by carbon tetrachloride (CCl4) and galactosamine (GalN)/lipopolysaccharides (LPS). Esculentoside A (EsA), isolated from the Chinese herb phytolacca esculenta, has the effect of modulating immune response, cell proliferation and apoptosis as well as anti-inflammatory effects. The present study is to evaluate the protective effect of EsA on CCl4 and GalN/LPS-induced acute liver injury. In vitro, CCK-8 assays showed that EsA had no cytotoxicity, while it significantly reduced levels of TNF-? and cell death rate challenged by CCl4. Moreover, EsA treatment up-regulated PPAR-? expression of LO2 cells and reduced levels of reactive oxygen species (ROS) challenged by CCl4. In vivo, EsA prevented mice from CCl4-induced liver histopathological damage. In addition, levels of AST and ALT were significantly decreased by EsA treatment. Furthermore, the mice treated with EsA had a lower level of TNF-?, Interleukin (IL)-1? and IL-6 in mRNA expression. EsA prevented MDA release and increased GSH-Px activity in liver tissues. Immunohistochemical staining showed that over-expression of F4/80 and CD11b were markedly inhibited by EsA. The western bolt results showed that EsA significantly inhibited CCl4-induced phosphonated IkBalpha (P-I?B) and ERK. Furthermore, EsA treatment also alleviated GalN/LPS-induced acute liver injury on liver enzyme and histopathological damage. Unfortunately, our results exhibited that EsA had no effects on CCl4-induced hepatocyte apoptosis which were showed by TUNEL staining and Bax, Caspase-3 and cleaved Caspase-3 expression. Our results proved that EsA treatment attenuated CCl4 and GalN/LPS-induced acute liver injury in mice and its protective effects might be involved in inhibiting inflammatory response and oxidative stress, but not apoptosis with its underlying mechanism associated with PPAR-?, NF-?B and ERK signal pathways.
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Ultrasound guidance for radial artery catheterization: an updated meta-analysis of randomized controlled trials.
PLoS ONE
PUBLISHED: 01-01-2014
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Since a previous meta-analysis reported that ultrasound guidance was associated with a higher first-attempt success rate in catheterization of the radial artery, a number of randomized controlled trials (RCTs) have reported inconsistent results. The aim of the present study is to conduct an updated meta-analysis to clarify the role of ultrasound guidance for radial artery catheterization.
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Alteration of antioxidant enzymes and associated genes induced by grape seed extracts in the primary muscle cells of goats in vitro.
PLoS ONE
PUBLISHED: 01-01-2014
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This study was conducted to investigate how the activity and expression of certain paramount antioxidant enzymes respond to grape seed extract (GSE) addition in primary muscle cells of goats. Gluteal primary muscle cells (PMCs) isolated from a 3-week old goat were cultivated as an unstressed cell model, or they were exposed to 100 µM H2O2 to establish a H2O2-stimulated cell model. The activities of catalase (CAT), superoxide dismutases (SOD) and glutathione peroxidases (GPx) in combination with other relevant antioxidant indexes [i.e., reduced glutathione (GSH) and total antioxidant capacity (TAOC)] in response to GSE addition were tested in the unstressed and H2O2-stimulated cell models, and the relative mRNA levels of the CAT, GuZu-SOD, and GPx-1 genes were measured by qPCR. In unstressed PMCs, GSE addition at the dose of 10 µg/ml strikingly attenuated the expression levels of CAT and CuZn-SOD as well as the corresponding enzyme activities. By contrast, in cells pretreated with 100 µM H2O2, the expression and activity levels of these two antioxidant enzymes were enhanced by GSE addition at 10 µg/ml. GSE addition promoted GPx activity in both unstressed and stressed PMCs, while the expression of the GPx 1 gene displayed partial divergence with GPx activity, which was mitigated by GSE addition at 10 µg/ml in unstressed PMCs. GSH remained comparatively stable except for GSE addition to H2O2-stimulated PMCs at 60 µg/ml, in which a dramatic depletion of GSH occurred. Moreover, GSE addition enhanced TAOC in unstressed (but not H2O2-stimulated) PMCs. GSE addition exerted a bidirectional modulating effect on the mRNA levels and activities of CAT and SOD in unstressed and stressed PMCs at a moderate dose, and it only exhibited a unidirectional effect on the promotion of GPx activity, reflecting its potential to improve antioxidant protection in ruminants.
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Epidemiological Study and Control Trial of Taeniid Cestode Infection in Farm Dogs in Qinghai Province, China.
J. Vet. Med. Sci.
PUBLISHED: 11-21-2013
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An epidemiological study and control trial were conducted to assess taeniid infection in farm dogs in Qinghai Province, China. To improve egg detection by fecal examination, a deworming step with praziquantel was incorporated into the sampling methodology. As a result, a marked increase in the number of egg-positive samples was observed in samples collected at 24 hr after deworming. Then, the fecal examination and barcoding of egg DNA were performed to assess the prevalence of taeniid species in dogs from Xinghai, Haiyan, Gangcha and Chengduo counties. Analysis of 277 dog feces revealed that taeniid cestodes, including Taenia spp. and Echinococcus granulosus, were highly prevalent in Xinghai (34.4%), but eggs were not found in Haiyan where a control trial on canine echinococcosis had been conducted 20 years previously. A control trial involving the administration of 5-10 mg/kg praziquantel to 90 farm dogs at 45-day intervals was conducted in Xinghai. The prevalence of taeniid cestodes in the dogs was reduced to 9.6% and 4.9% after one and two years, respectively, indicating that some dogs were not administered praziquantel properly. A questionnaire survey of farmers in Xinghai and Haiyan revealed that most farmers in Xinghai were not familiar with echinococcosis or the transmission route of the disease, while most farmers in Haiyan had a more thorough understanding of the disease. The findings implied that a program for educating local farmers would be important for efficiently controlling canine taeniid infection in the region.
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[Phylogenetic analysis of closely related Leuconostoc citreum species based on partial housekeeping genes].
Wei Sheng Wu Xue Bao
PUBLISHED: 11-08-2013
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Using the 16S rRNA, dnaA, murC and pyrG gene sequences, we identified the phylogenetic relationship among closely related Leuconostoc citreum species.
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Dual functionalization of poly(?-caprolactone) film surface through supramolecular assembly with the aim of promoting in situ endothelial progenitor cell attachment on vascular grafts.
Biomacromolecules
PUBLISHED: 10-25-2013
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In this study, we developed a method for the dual functionalization of a poly(?-caprolactone) (PCL) surface by means of the supramolecular assembly technology. Polyethylene glycol (PEG), with resistance to protein adsorption, and TPSLEQRTVYAK (TPS) peptide, which can specifically bind endothelial progenitor cells (EPCs), were immobilized on the PCL surface through host-guest inclusion complexation. The chemical composition as well as the hydrophilic/hydrophobic property of the functionalized surface was characterized by X-ray photoelectron spectroscopy and water contact angle measurements. The relative composition of two functional molecules on the dually functionalized surface was further analyzed by fluorescence quantification. Finally, the fibrinogen adsorption, platelet adhesion and activation, and selective attachment of cells were systematically evaluated on the functionalized surface. The results show that the presence of PEG evidently inhibited the adsorption of plasma protein and platelet adhesion, thus reducing the possibility of thrombus formation on the functionalized surface. At the same time, the TPS-functionalized surface demonstrated enhanced attachment toward EPC compared with the surfaces in the absence of TPS functionalization. For the surface functionalized by both PEG and TPS, the functions provided by each component have been well demonstrated. The relative composition of the PEG and TPS could be further fine-tuned by adjusting the feeding ratio. All these results indicate that the dually functionalized surface developed in this study is a suitable candidate for vascular graft to induce and promote in situ endothelialization.
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Elevated [CO2] magnifies isoprene emissions under heat and improves thermal resistance in hybrid aspen.
J. Exp. Bot.
PUBLISHED: 10-23-2013
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Isoprene emissions importantly protect plants from heat stress, but the emissions become inhibited by instantaneous increase of [CO2], and it is currently unclear how isoprene-emitting plants cope with future more frequent and severe heat episodes under high [CO2]. Hybrid aspen (Populus tremula x Populus tremuloides) saplings grown under ambient [CO2] of 380 ?mol mol(-1) and elevated [CO2] of 780 ?mol mol(-1) were used to test the hypothesis that acclimation to elevated [CO2] reduces the inhibitory effect of high [CO2] on emissions. Elevated-[CO2]-grown plants had greater isoprene emission capacity and a stronger increase of isoprene emissions with increasing temperature. High temperatures abolished the instantaneous [CO2] sensitivity of isoprene emission, possibly due to removing the substrate limitation resulting from curbed cycling of inorganic phosphate. As a result, isoprene emissions were highest in elevated-[CO2]-grown plants under high measurement [CO2]. Overall, elevated growth [CO2] improved heat resistance of photosynthesis, in particular, when assessed under high ambient [CO2] and the improved heat resistance was associated with greater cellular sugar and isoprene concentrations. Thus, contrary to expectations, these results suggest that isoprene emissions might increase in the future.
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An Epidemiological Study of Hypoderma Infection and Control Using Ivermectin in Yaks in Qinghai Province, China.
J. Vet. Med. Sci.
PUBLISHED: 10-10-2013
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The prevalence of Hypoderma spp. in yaks grazed in the east of Qinghai province was investigated in 2008. In this area, the prevalence in young yaks (1- to 3-year-old) was very high at 82.2-98.7%, whilst in adult yaks (4-year-old and older), the prevalence was 42.4-50.6%. The seasonal development and migration pattern of Hypoderma larvae in yak bodies was found to be similar for different locations in this area. The numbers of first, second and third instar larvae detected in yak bodies peaked in October, December and March, respectively. Different doses of ivermectin (125 to 500 µg/kg body weight) almost completely dewormed the larvae from yaks, suggesting that using a quarter of the prescribed dose (500 µg/kg body weight) was effective. In October of each year between 2009 and 2012, ivermectin (125 µg/kg body weight) was administered to a total of 562,995 yaks grazed in four counties in Qinghai province, and the pevalence of Hypoderma larval infection in yaks was reduced to 0.5-1.0%.
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Cotransplantation of haploidentical hematopoietic and umbilical cord mesenchymal stem cells for severe aplastic anemia: Successful engraftment and mild GVHD.
Stem Cell Res
PUBLISHED: 09-26-2013
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Haploidentical hematopoietic stem-cell transplantation (haplo-HSCT) is associated with an increased risk of graft failure and severe graft-versus-host disease (GVHD). Mesenchymal stromal cells (MSCs) have been shown to support in vivo normal hematopoiesis and to display potent immunesuppressive effects. We cotransplanted the culture-expanded third-party donor-derived umbilical cord MSCs (UC-MSCs) in 21 young people with severe aplastic anemia (SAA) undergoing haplo-HSCT without T-cell-depleted. We observed that all patients had sustained hematopoietic engraftment without any adverse UC-MSC infusion-related events. Furthermore, we did not observe any increase in severe aGVHD. These data suggest that UC-MSCs, possibly thanks to their potent immunosuppressive effect on allo-reactive host T lymphocytes escaping the preparative regimen, reduce the risk of graft failure and severe GVHD in haplo-HSCT.
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Deep vein thrombosis after total hip arthroplasty and total knee arthroplasty in patients with previous ischemic stroke.
Int J Low Extrem Wounds
PUBLISHED: 09-16-2013
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The present study evaluated the prevalence and therapy of deep vein thrombosis (DVT) after total hip arthroplasty (THA) and total knee arthroplasty (TKA) in 57 patients with previous ischemic stroke. Postoperative anticoagulants were used for DVT prophylaxis, and batroxobin and prolonged anticoagulants were used for thrombolysis in DVT subjects. The incidence of DVT after THA and TKA in patients with previous ischemic stroke was 16.2% and 20%, respectively. No bleeding complications were observed and no new ischemic stroke occurred during the following 3 months. The prevalence DVT after THA and TKA in patients with previous ischemic stroke was not specific, and the treatment of DVT with batroxobin and anticoagulants was effective and safe.
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Postoperative plasma D-dimer value for predicting deep venous thrombosis following hip arthroplasty with nadroparin prophylaxis.
Hip Int
PUBLISHED: 09-10-2013
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The aim of the study was to assess the value of D-dimer as an event predicitor for deep vein thrombosis (DVT) in patients given low molecular weight heparin (LMWH) after total hip arthroplasty (THA). Plasma D-dimer levels were obtained preoperatively and at days 1, 3, and 7 postoperatively in 83 consecutive patients undergoing THA treated with nadroparin prophylaxis plus intermittent pneumatic compression. Unilateral ascending venography was performed at postoperative day 7 or 8. There was a significant difference between the D-dimer levels in the DVT group (28 patients) and non-DVT group (55 patients) on each day (P<0.01). ROC analysis showed the AUC on postoperative days 1, 3 and 7 was 0.706, 0.712 and 0.772 respectively. The D-dimer concentration on postoperative day 1, day 3 or day 7 is of moderate predicting value of DVT in patients undergoing THA, treated with nadroparin prophylaxis plus intermittent pneumatic compression.
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Application of (1)h NMR spectroscopy-based metabolomics to sera of tuberculosis patients.
J. Proteome Res.
PUBLISHED: 09-10-2013
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Nuclear magnetic resonance (NMR) spectroscopy is an ideal platform for the metabolic analysis of biofluids due to its high reproducibility, nondestructiveness, nonselectivity in metabolite detection, and the ability to simultaneously quantify multiple classes of metabolites. Tuberculosis (TB) is a chronic wasting inflammatory disease characterized by multisystem involvement, which can cause metabolic derangements in afflicted patients. In this study, we combined multivariate pattern recognition (PR) analytical techniques with (1)H NMR spectroscopy to explore the metabolic profile of sera from TB patients. A total of 77 serum samples obtained from patients with TB (n = 38) and healthy controls (n = 39) were investigated. Orthogonal partial least-squares discriminant analysis (OPLS-DA) was capable of distinguishing TB patients from controls and establishing a TB-specific metabolite profile. A total of 17 metabolites differed significantly in concentration between the two groups. Serum samples from TB patients were characterized by increased concentrations of 1-methylhistidine, acetoacetate, acetone, glutamate, glutamine, isoleucine, lactate, lysine, nicotinate, phenylalanine, pyruvate, and tyrosine, accompanied by reduced concentrations of alanine, formate, glycine, glycerolphosphocholine, and low-density lipoproteins relative to control subjects. Our study reveals the metabolic profile of sera from TB patients and indicates that NMR-based methods can distinguish TB patients from healthy controls. NMR-based metabolomics has the potential to be developed into a novel clinical tool for TB diagnosis or therapeutic monitoring and could contribute to an improved understanding of disease mechanisms.
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Tyrosine phosphorylation of mig6 reduces its inhibition of the epidermal growth factor receptor.
ACS Chem. Biol.
PUBLISHED: 09-06-2013
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Under physiological conditions, epidermal growth factor receptor (EGFR) tyrosine kinase activity is tightly controlled through the coordinated action of both positive and negative regulators. Aberrant EGFR activation occurs frequently in many cancer types, and the endogenous EGFR feedback inhibitor, Mig6/RALT, is more efficiently phosphorylated by oncogenic EGFR variants. We have utilized expressed protein ligation to generate semisynthetic Tyr394 phosphorylated and unphosphorylated forms of the Mig6 protein and shown that phosphorylation of Mig6 reduces its ability to inhibit purified, near full-length EGFR (tEGFR). We also demonstrate that the kinetic parameters of tEGFR are similar whether solubilized in detergent or reconstitutued in nanodisc bilayers. These findings suggest a mechanism by which EGFR and its family members evade negative regulation by Mig6 under pathological conditions.
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Synthesis and activity of novel acylthiourea with hydantoin.
Int J Mol Sci
PUBLISHED: 07-23-2013
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The 41 novel acylthiourea derivatives with hydantoin were synthesized in moderate to excellent yields by using 5-(4-aminophenyl)- and 5-(4-aminobenzyl)-hydantoin or 5-(4-aminobenzyl)-thiohydantoin as raw materials and characterized by IR, 1H NMR spectra and elementary analysis. The preliminary bioassay showed that these compounds exhibit certain selectively herbicidal activities with the 91%, 94% and 87% inhibition rates of 7l, 8o and 8p against B. campestris, 100%, 100% and 95% efficacy against B. campestris in a greenhouse test, respectively. 7a, 7b, 7c and 7d exhibited 74%, 79%, 79% and 71% inhibition rates against F. oxysporum, respectively.
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Mesenchymal stromal cells improve survival during sepsis in the absence of heme oxygenase-1: the importance of neutrophils.
Stem Cells
PUBLISHED: 07-19-2013
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The use of mesenchymal stromal cells (MSCs) for treatment of bacterial infections, including systemic processes like sepsis, is an evolving field of investigation. This study was designed to investigate the potential use of MSCs, harvested from compact bone, and their interactions with the innate immune system, during polymicrobial sepsis induced by cecal ligation and puncture (CLP). We also wanted to elucidate the role of endogenous heme oxygenase (HO)-1 in MSCs during a systemic bacterial infection. MSCs harvested from the bones of HO-1 deficient (-/-) and wild-type (+/+) mice improved the survival of HO-1(-/-) and HO-1(+/+) recipient mice when administered after the onset of polymicrobial sepsis induced by CLP, compared with the administration of fibroblast control cells. The MSCs, originating from compact bone in mice, enhanced the ability of neutrophils to phagocytize bacteria in vitro and in vivo and to promote bacterial clearance in the peritoneum and blood after CLP. Moreover, after depleting neutrophils in recipient mice, the beneficial effects of MSCs were entirely lost, demonstrating the importance of neutrophils for this MSC response. MSCs also decreased multiple organ injury in susceptible HO-1(-/-) mice, when administered after the onset of sepsis. Taken together, these data demonstrate that the beneficial effects of treatment with MSCs after the onset of polymicrobial sepsis is not dependent on endogenous HO-1 expression, and that neutrophils are crucial for this therapeutic response.
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Extracellular matrix composition significantly influences pancreatic stellate cell gene expression pattern: role of transgelin in PSC function.
Am. J. Physiol. Gastrointest. Liver Physiol.
PUBLISHED: 07-18-2013
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Activated pancreatic stellate cells (PSCs) are responsible for the fibrotic matrix of chronic pancreatitis and pancreatic cancer. In vitro protocols examining PSC biology have usually involved PSCs cultured on plastic, a nonphysiological surface. However, PSCs cultured on physiological matrices, e.g., Matrigel (normal basement membrane) and collagen (fibrotic pancreas), may have distinctly different behaviors compared with cells cultured on plastic. Therefore, we aimed to 1) compare PSC gene expression after culture on plastic, Matrigel, and collagen I; 2) validate the gene array data for transgelin, the most highly dysregulated gene in PSCs grown on activating vs. nonactivating matrices, at mRNA and protein levels; 3) examine the role of transgelin in PSC function; and 4) assess transgelin expression in human chronic pancreatitis sections. Culture of PSCs on different matrices significantly affected their gene expression pattern. 146, 619, and 432 genes, respectively, were differentially expressed (P < 0.001) in PSCs cultured on collagen I vs. Matrigel, Matrigel vs. plastic, and collagen I vs. plastic. The highest fold change (12.5-fold upregulation) in gene expression in cells on collagen I vs. Matrigel was observed for transgelin (an actin stress fiber-associated protein). Transgelin was significantly increased in activated PSCs vs. quiescent PSCs. Silencing transgelin expression decreased PSC proliferation and also reduced platelet-derived growth factor-induced PSC migration. Notably, transgelin was highly expressed in chronic pancreatitis in stromal areas and periacinar spaces but was absent in acinar cells. These findings suggest that transgelin is a potentially useful target protein to modulate PSC function so as to ameliorate pancreatic fibrosis.
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[Diagnosis and treatment of complicated foreign bodies in the middle ear (5 cases reported)].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 07-10-2013
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To investigate the sources of foreign bodies in the middle ear, and to analyze experience and lessons of clinical diagnosis and therapy.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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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.