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Find video protocols related to scientific articles indexed in Pubmed.
A Chemical Tuned Strategy to Develop Novel Irreversible EGFR-TK Inhibitors with Improved Safety and Pharmacokinetic Profiles.
J. Med. Chem.
PUBLISHED: 11-20-2014
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Gatekeeper T790M mutation in EGFR is the most prevalent factor underlying acquired resistance. Acrylamide-bearing quinazoline derivatives are powerful irreversible inhibitors for overcoming resistance. Nevertheless, concerns about the risk of non-specific covalent modification have motivated the development of novel cysteine-targeting inhibitors. In this paper, we demonstrate that fluoro-substituted olefins can be tuned to alter Michael addition reactivity. Incorporation of these olefins into the quinazoline templates produced potent EGFR inhibitors with improved safety and pharmacokinetic properties. A lead compound 5a was validated against EGFRWT, EGFR T790M as well as A431 and H1975 cancer cell lines. Additionally, compound 5a displayed a weaker inhibition against the EGFR-independent cancer cell line SW620 when compared withafatinib. Oral administration of 5a at a dose of 30mg/kg induced tumor regression in a murine-EGFRL858R/T790M driven H1975 xenograft model. Also, 5a exhibited improved oral bioavailability and safety, as well as favorable tissue distribution properties and enhanced brain uptake. These findings provide the basis of a promising strategy toward the treatment of NSCLC patients with drug resistance.
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BaMn9[VO4]6(OH)2: A Unique Canted Antiferromagnet with a Chiral "Paddle-Wheel" Structural Feature.
Inorg Chem
PUBLISHED: 11-20-2014
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BaMn9[VO4]6(OH)2 was synthesized by hydrothermal methods. We evaluated the crystal structure based on the two possible space groups P213 and Pa3? [a = 12.8417(2) Å] using single-crystal and powder X-ray diffraction techniques. The structure contains three-dimensionally linked Mn9 units of a chiral "paddle-wheel" type. Experimental IR and Raman spectra were analyzed in terms of fundamental vanadate and hydroxide vibrational modes. The magnetic properties were investigated, and the specific heat in applied fields was studied. The dominant magnetic interactions (Mn(2+), S = (5)/2) are of antiferromagnetic origin, as indicated by a Curie-Weiss fit above 175 K with ? ? -200 K. Canting of the spins on the geometrically frustrated triangle segment of the structural feature is considered to account for the ferrimagnetic type of long-range order at TC ? 18 K. We propose a model for the spin structure in the ordered regime. Dielectric constants were measured and indicate a magnetodielectric effect at TC, which is assigned to spin-lattice coupling.
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Synthesis and Characterization of the Platinum-Substituted Keggin Anion ?-H2SiPtW11O40(4-)
Inorg Chem
PUBLISHED: 11-20-2014
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Acidification of an aqueous solution of K8SiW11O39 and K2Pt(OH)6 to pH 4 followed by addition of excess tetramethylammonium (TMA) chloride yielded a solid mixture of TMA salts of H2SiPtW11O40(4-) (1) and SiW12O40(4-) (2). The former was separated from the latter by extraction into an aqueous solution and converted into tetra-n-butylammonium (TBA) and potassium salts TBA-1 and K-1. The ?-H2SiPtW11O40(4-) was identified as a monosubstituted Keggin anion using elemental analysis, IR spectroscopy, X-ray crystallography, electrospray ionization mass spectrometry, (195)Pt NMR spectroscopy, (183)W NMR spectroscopy, and (183)W-(183)W 2D INADEQUATE NMR spectroscopy. Both TBA-1 and K-1 readily cocrystallized with their unsubstituted Keggin anion salts, TBA-2 and K-2, respectively, providing an explanation for the historical difficulty of isolating certain platinum-substituted heteropolyanions in pure form.
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Discovery and Characterization of the Tuberculosis Drug Lead Ecumicin.
Org. Lett.
PUBLISHED: 11-20-2014
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The new tuberculosis (TB) lead ecumicin (1), a cyclic tridecapeptide, was isolated from Nonomuraea sp. MJM5123, following a high-throughput campaign for anti-TB activity. The large molecular weight of 1599 amu detected by LC-HR-MS precluded the initial inference of its molecular formula. The individual building blocks were identified by extensive NMR experiments. The resulting two possible planar structures were distinguished by LC-MS(2). Determination of absolute configuration and unambiguous structural confirmation were carried out by X-ray crystallography and Marfey's analysis.
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Characterization of a subpopulation of developing cortical interneurons from human iPSCs within serum free embryoid bodies.
Am. J. Physiol., Cell Physiol.
PUBLISHED: 11-15-2014
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The production and isolation of forebrain interneuron progenitors is essential for both understanding cortical development and developing cell-based therapies for developmental and neurodegenerative disorders. Here we demonstrate production of a population of putative calretinin-positive (CalR+)-bipolar interneurons that express markers consistent with caudal ganglionic eminence identities Using serum-free embryoid bodies (SFEBs) generated from human inducible pluripotent stem cells (iPSCs) we demonstrate that these interneuron progenitors exhibit morphological, immunocytochemical, and electrophysiological hallmarks of developing cortical interneurons. Finally, we develop a fluorescence-activated cell sorting (FACS) strategy to isolate interneuron progenitors from SFEBs to allow the development of a purified population of these cells. The identification of this critical neuronal cell type within iPSC-derived SFEBs is an important and novel step in describing cortical development in within this iPSC preparation.
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Correlation Between Helicobacter pylori Infection, IgE Hypersensitivity, and Allergic Disease in Korean Adults.
Helicobacter
PUBLISHED: 09-27-2014
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The correlation between allergic disease and Helicobacter pylori infection is still controversial in endemic areas. The aim of this study was to determine whether H. pylori infection is related to allergic disease and/or immunoglobulin E (IgE) hypersensitivity in Korean adults.
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Heterolayered, one-dimensional nanobuilding block mat batteries.
Nano Lett.
PUBLISHED: 09-22-2014
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The rapidly approaching smart/wearable energy era necessitates advanced rechargeable power sources with reliable electrochemical properties and versatile form factors. Here, as a unique and promising energy storage system to address this issue, we demonstrate a new class of heterolayered, one-dimensional (1D) nanobuilding block mat (h-nanomat) battery based on unitized separator/electrode assembly (SEA) architecture. The unitized SEAs consist of wood cellulose nanofibril (CNF) separator membranes and metallic current collector-/polymeric binder-free electrodes comprising solely single-walled carbon nanotube (SWNT)-netted electrode active materials (LiFePO4 (cathode) and Li4Ti5O12 (anode) powders are chosen as model systems to explore the proof of concept for h-nanomat batteries). The nanoporous CNF separator plays a critical role in securing the tightly interlocked electrode-separator interface. The SWNTs in the SEAs exhibit multifunctional roles as electron conductive additives, binders, current collectors and also non-Faradaic active materials. This structural/physicochemical uniqueness of the SEAs allows significant improvements in the mass loading of electrode active materials, electron transport pathways, electrolyte accessibility and misalignment-proof of separator/electrode interface. As a result, the h-nanomat batteries, which are easily fabricated by stacking anode SEA and cathode SEA, provide unprecedented advances in the electrochemical performance, shape flexibility and safety tolerance far beyond those achievable with conventional battery technologies. We anticipate that the h-nanomat batteries will open 1D nanobuilding block-driven new architectural design/opportunity for development of next-generation energy storage systems.
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Arabidopsis AtERF71/HRE2 functions as transcriptional activator via cis-acting GCC box or DRE/CRT element and is involved in root development through regulation of root cell expansion.
Plant Cell Rep.
PUBLISHED: 09-11-2014
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AtERF71/HRE2 binds to GCC box or DRE/CRT as transcription activator and plays an important role in root development via root cell expansion regulation. AtERF71/HRE2 transcription factor, a member of the AP2/ERF family, plays a key role in the stress response. GCC box and DRE/CRT, both essential cis-acting elements, have been shown to be recognized by AP2/ERF family transcription factors. However, it remains unclear whether or not AtERF71/HRE2 directly interacts with GCC box and/or DRE/CRT. Here, we showed that AtERF71/HRE2 binds to GCC box and DRE/CRT by electrophoretic mobility shift assay (EMSA). Binding of AtERF71/HRE2 to GCC box and DRE/CRT was also detected by fluorescence measurement and surface plasmon resonance spectroscopy (BIAcore) experiments. Folding properties of AtERF71/HRE2 proteins were characterized by CD spectroscopy, and AtERF71/HRE2 showed thermal stability as evidenced by two endothermic peaks (T d) at 53 and 65 °C. In addition, AtERF71/HRE2 showed transcriptional activation activity via GCC box and DRE/CRT in Arabidopsis protoplasts. Interestingly, AtERF71/HRE2 OXs showed increased primary root length due to elevated root cell expansion. Our data indicate that AtERF71/HRE2 binds to both GCC box and DRE/CRT, transactivates expression of genes downstream via GCC box or DRE/CRT, and plays an important role in root development through regulation of root cell expansion.
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Orange juice intake reduces patient discomfort and is effective for bowel cleansing with polyethylene glycol during bowel preparation.
Dis. Colon Rectum
PUBLISHED: 09-10-2014
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Many patients report discomfort because of the unpleasant taste of bowel preparation solutions.
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Tuning gelation kinetics and mechanical rigidity of ?-hairpin peptide hydrogels via hydrophobic amino acid substitutions.
ACS Appl Mater Interfaces
PUBLISHED: 08-08-2014
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Self-assembling peptide hydrogels with faster gelation kinetics and higher mechanical rigidity are favorable for their practical applications. A design strategy to control the folding, self-assembly, and hydrogelation of ?-hairpin peptides via hydrophobic amino acid substitutions has been explored in this study. Isoleucine has higher hydrophobicity and stronger propensity for ?-sheet hydrogen bonding than valine. After the valine residues of MAX1 (VKVKVKVKV(D)PPTKVKVKVKV-NH2) were replaced with isoleucines, oscillatory rheometry and circular dichroism (CD) spectroscopy characterizations indicated that the variants had clearly faster self-assembly and hydrogelation rates and that the resulting gels displayed higher mechanical stiffness. Transmission electron microscopy (TEM) indicated the parent MAX1 and its variants all formed networks of long and entangled fibrils with the similar diameters of ?3 nm, suggesting little effect of hydrophobic substitutions on the self-assembled morphology. The MAX1I8 (IKIKIKIKV(D)PPTKIKIKIKI-NH2) hydrogel showed the fastest gelation rate (within 5 min) and the highest gel rigidity with the series, supporting the homogeneous cell distribution within its 3D scaffold. In addition, the MAX1I8 hydrogel showed quick shear-thinning and rapid recovery upon cessation of shear strain, and the MTT and immunological assays indicated its low cytotoxicity and good biocompatibility. These features are highly attractive for its widespread use in 3D cell culturing and regenerative medical treatments.
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Multifunctional graphene quantum dots for simultaneous targeted cellular imaging and drug delivery.
Colloids Surf B Biointerfaces
PUBLISHED: 08-07-2014
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This study demonstrates that ligand-modified graphene quantum dots (GQDs) facilitate the simultaneous operation of multiple tasks without the need for external dyes. These tasks include selective cell labeling, targeted drug delivery, and real-time monitoring of cellular uptake. Folic acid (FA)-conjugated GQDs are synthesized and utilized to load the antitumor drug doxorubicin (DOX). The fabricated nanoassembly can unambiguously discriminate cancer cells from normal cells and efficiently deliver the drug to targeted cells. The inherent stable fluorescence of GQDs enables real-time monitoring of the cellular uptake of the DOX-GQD-FA nanoassembly and the consequent release of drugs. The nanoassembly is specifically internalized rapidly by HeLa cells via receptor-mediated endocytosis, whereas DOX release and accumulation are prolonged. In vitro toxicity data suggest that the DOX-GQD-FA nanoassembly can target HeLa cells differentially and efficiently while exhibiting significantly reduced cytotoxicity to non-target cells.
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Development of a selective agar plate for the detection of Campylobacter spp. in fresh produce.
Int. J. Food Microbiol.
PUBLISHED: 08-02-2014
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This study was conducted to develop a selective medium for the detection of Campylobacter spp. in fresh produce. Campylobacter spp. (n=4), non-Campylobacter (showing positive results on Campylobacter selective agar) strains (n=49) isolated from fresh produce, indicator bacteria (n=13), and spoilage bacteria isolated from fresh produce (n=15) were plated on four Campylobacter selective media. Bolton agar and modified charcoal cefoperazone deoxycholate agar (mCCDA) exhibited higher sensitivity for Campylobacter spp. than did Preston agar and Hunt agar, although certain non-Campylobacter strains isolated from fresh produce by using a selective agar isolation method, were still able to grow on Bolton agar and mCCDA. To inhibit the growth of non-Campylobacter strains, Bolton agar and mCCDA were supplemented with 5 antibiotics (rifampicin, polymyxin B, sodium metabisulfite, sodium pyruvate, ferrous sulfate) and the growth of Campylobacter spp. (n=7) and non-Campylobacter strains (n=44) was evaluated. Although Bolton agar supplemented with rifampicin (BR agar) exhibited a higher selectivity for Campylobacter spp. than did mCCDA supplemented with antibiotics, certain non-Campylobacter strains were still able to grow on BR agar (18.8%). When BR agar with various concentrations of sulfamethoxazole-trimethoprim were tested with Campylobacter spp. (n=8) and non-Campylobacter (n=7), sulfamethoxazole-trimethoprim was inhibitory against 3 of 7 non-Campylobacter strains. Finally, we validated the use of BR agar containing 50mg/L sulfamethoxazole (BRS agar) or 0.5mg/L ciprofloxacin (BRCS agar) and other selective agars for the detection of Campylobacter spp. in chicken and fresh produce. All chicken samples were positive for Campylobacter spp. when tested on mCCDA, BR agar, and BRS agar. In fresh produce samples, BRS agar exhibited the highest selectivity for Campylobacter spp., demonstrating its suitability for the detection of Campylobacter spp. in fresh produce.
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Myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs.
Heart Vessels
PUBLISHED: 08-01-2014
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The aim of this study was to explore myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs. 24 male pigs (34.6 ± 1.3 kg) were randomly divided into three groups-control group, drug therapy group, and ECMO group. Myocardial infarction model was created in drug therapy group and ECMO group by ligating coronary artery. When cardiogenic shock occurred, drugs were given in drug therapy group and ECMO began to work in ECMO group. The pigs were killed 24 h after cardiogenic shock. Compared with in drug therapy group, left ventricular end-diastolic pressure in ECMO group decreased significantly 6 h after ligation (P < 0.05). At the end of the experiments, LV - dp/dt among three groups was significantly different, drug therapy group < ECMO group < control group. There was no difference in LV + dp/dt between drug therapy group and ECMO group. Compared with drug group, myocardial infarct size of ECMO group did not reduce significantly, but myocardial enzyme and troponin-I decreased significantly. Compared with drug therapy, ECMO improves left ventricular diastolic function, and may improve systolic function. ECMO cannot reduce myocardial infarct size without revascularization, but may have positive effects on ischemic areas by avoiding further injuring.
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Hemorrhagic Recurrence in Diffuse Astrocytoma without Malignant Transformation.
Brain Tumor Res Treat
PUBLISHED: 07-31-2014
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Although uncommon, hemorrhage can be a complication of low grade glioma with an unfavorable prognosis such as transformation to higher grade glioma. To our knowledge, hemorrhagic recurrence of World Health Organization Grade II, diffuse astrocytoma without malignant transformation has not been reported. Thus, we report a case of diffuse astrocytoma with hemorrhagic recurrence without malignant transformation. The patient had undergone craniotomy and tumor removal 7 years previously. Annual follow-up MRIs had shown evidence of slow tumor recurrence. With the sudden onset of seizure, the patient was diagnosed as hemorrhagic recurrence and underwent second tumor removal highly suspecting malignant change into higher grade glioma. Histopathology confirmed diffuse astrocytoma without malignant changes. As the patient's postoperative condition was excellent, we plan to withhold chemotherapy and radiation therapy for use as a later treatment option.
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Adult-Onset Sellar and Suprasellar Atypical Teratoid Rhabdoid Tumor Treated with a Multimodal Approach: A Case Report.
Brain Tumor Res Treat
PUBLISHED: 07-15-2014
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We report a very rare case of sellar and suprasellar atypical teratoid rhabdoid tumor (ATRT) in a 42-year-old female patient. The tumor was removed subtotally with a transsphenoidal approach. Histopathologic study showed rhabdoid cells with prominent nucleoli and abundant cytoplasm. Immunohistochemistry for INI1 was completely negative in the tumor cells, consistent with ATRT. After surgery, she received radiotherapy including spinal irradiation with proton beam therapy and subsequent chemotherapy, with no evidence of recurrence for more than 2 years. Up to date, this is the 8th case of an adult-onset ATRT in the sellar or suprasellar region. Despite its rarity, ATRTs should be considered in the differential diagnosis of an unclear malignant sellar or suprasellar lesion in adult patients and the treatment strategies for adult ATRT patients could be differentiated from those of pediatric ATRT patients.
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Endoscopic flushing with pronase improves the quantity and quality of gastric biopsy: a prospective study.
Endoscopy
PUBLISHED: 07-14-2014
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Pronase, a proteolytic enzyme, is known to improve mucosal visibility during esophagogastroduodenoscopy (EGD), but little is known about its effects on gastric biopsy. This study assessed whether endoscopic flushing with pronase improves the quality of gastric biopsy.
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Morphology-tunable synthesis of ZnO nanoforest and its photoelectrochemical performance.
Nanoscale
PUBLISHED: 06-24-2014
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Understanding and manipulating synthesis reactions and crystal growth mechanisms are keys to designing and constructing the morphology and functional properties of advanced materials. Herein, the morphology-controlled synthesis of three-dimensional (3D) ZnO nanoforests is reported via a facile hydrothermal route. Specifically, the respective and synergistic influence of polyethylenimine (PEI) and ammonia on tuning the architecture of ZnO nanoforests is systematically studied. An in-depth understanding of the mechanism of hydrothermal growth is vital for advancing this facile approach and incorporating special 3D nanostructures into versatile nanomanufacturing. More importantly, its unique architectural characteristics endow the willow-like ZnO nanoforest with prominent photoelectrochemical water splitting performance, including small charge transfer resistance, long photoelectron lifetime, a high photocurrent density of 0.919 mA cm(-2) at +1.2 V (vs. Ag/AgCl), and more important, a high photoconversion efficiency of 0.299% at 0.89 V (vs. RHE), which leads the realm of homogeneous ZnO nanostructures. In all, it is expected that this work will open up an unprecedented avenue to govern desirable 3D ZnO nanostructures and broaden the application potentials of 3D nanotechnology.
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Dimanganese(II) hydroxide vanadate, Mn2(OH)[VO4].
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 06-11-2014
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Dimanganese(II) hydroxide vanadate was obtained from hydro-thermal reactions. The crystal structure of the title compound is isotypic with that of Zn2(OH)[VO4]. Three crystallographically independent Mn(2+) ions are present, one (site symmetry .m.) with a distorted trigonal-bipyramidal and two (site symmetries .m. and 1) with distorted octa-hedral coordination spheres. These polyhedra are linked through common edges, forming a corrugated layer-type of structure extending parallel to (100). A three-dimensional framework results via additional Mn-O-V-O-Mn connectivities involving the two different tetra-hedral [VO4] units (each with point-group symmetry .m.). O-H?O hydrogen bonds (one bifurcated) between the OH functions (both with point-group symmetry .m.) and the [VO4] units complete this arrangement.
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ID1201, the ethanolic extract of the fruit of Melia toosendan ameliorates impairments in spatial learning and reduces levels of amyloid beta in 5XFAD mice.
Neurosci. Lett.
PUBLISHED: 06-03-2014
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A previous study has demonstrated the anti-amyloidogenic effects of the ethanolic extract of Meliae Fructus (ID1201) using cell lines with stably expressed human Swedish mutant APP695 and ?-secretase 1, and 5Xfamilial AD (FAD) mice carrying five mutations. Here, we investigated the effects of ID1201 on cognitive impairment in 5XFAD mice. Daily administration of ID1201 was commenced at 3 months of age and continued for 3 months. Mice were serially trained in cued/response and place/spatial training tasks in the Morris water maze. After this training, testing for strategy preference was conducted. Non-transgenic control mice with vehicle treatment, vehicle-treated 5XFAD, and ID1201-treated 5XFAD mice showed equivalent performance in cued/response training. However, as training progressed to the subsequent place/spatial learning, vehicle-treated control and ID1201-treated 5XFAD mice differed significantly from vehicle-treated 5XFAD mice in measures of spatial learning (search error and adaptive spatial learning strategy). In the strategy preference test that followed, control mice preferred a place/spatial strategy relative to vehicle-treated 5XFAD mice, but differences between ID1201-treated 5XFAD mice and vehicle-treated 5XFAD mice were not significant. Additionally, ID1201 treatment reduced hippocampal levels of insoluble A?42 and increased cortical levels of soluble amyloid precursor protein ?. These results indicate that ID1201 may possess potential as a therapeutic agent for Alzheimer's disease by decreasing A? deposits.
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Growth characteristics and biofilm formation of various spoilage bacteria isolated from fresh produce.
J. Food Sci.
PUBLISHED: 05-27-2014
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This study investigated the characteristics of spoilage bacteria isolated from fresh produce including growth at various temperatures, biofilm formation, cell hydrophobicity, and colony spreading. The number of spoilage bacteria present when stored at 35 °C was significantly greater than when stored at lower temperatures, and maximum population size was achieved after 10 h. However, Bacillus pumilus, Dickeya zeae, Pectobacterium carotovorum subsp. Carotovorum Pcc21, and Bacillus pumilus (RDA-R) did not grow at the storage temperature of 5 °C. The biofilm formation by Clavibacter michiganensis, Acinetobacter calcoaceticus, and A. calcoaceticus (RDA-R) are higher than other spoilage bacteria. Biofilm formation showed low correlation between hydrophobicity, and no significant correlation with colony spreading. These results might be used for developing safe storage guidelines for fresh produce at various storage temperatures, and could be basic information on the growth characteristics and biofilm formation properties of spoilage bacteria from fresh produce.
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A meningomyelocele with normal intracranial signs on ultrasound and false-negative amniotic fluid alpha-fetoprotein and acetylcholinesterase.
Obstet Gynecol Sci
PUBLISHED: 05-15-2014
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Neural tube defects are the major targets of prenatal diagnoses, along with Down syndrome. Prenatal diagnosis of spina bifida is possible at second trimester of gestation through ?-fetoprotein and acetylcholinesterase biochemistry assays and ultrasound. In particular, the discovery of characteristic intracranial signs on ultrasound leads to a very high diagnosis rate. However, it is rare for spina bifida to present without intracranial signs while also showing normal values of maternal serum ?-fetoprotein, amniotic fluid ?-fetoprotein, and acetylcholinesterase. In our hospital, a fetus with spina bifida was delivered at 37+5 weeks' gestation by cesarean section, and was continually followed up over 2 years to date.
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Curcumin prevents diabetic nephropathy against inflammatory response via reversing caveolin-1 Tyr(14) phosphorylation influenced TLR4 activation.
Int. Immunopharmacol.
PUBLISHED: 05-14-2014
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Inflammation is involved in the development and/or progression of diabetic nephropathy (DN). Curcumin has been reported for its anti-inflammation activity in DN. However, the mechanisms involved in the renoprotective effects of curcumin have not been clearly demonstrated. In this study, we hypothesized that curcumin affected high glucose (HG)-induced inflammation profiles in vivo and in vitro and then prevented renal injury in diabetic rats via reversing cav-1 Tyr(14) phosphorylation that influenced TLR4 activation. Streptozotocin (STZ)-induced diabetic rats received vehicle or curcumin for twelve weeks and podocytes were treated with HG in the presence or absence of curcumin in vitro. To further evaluate the effect of cav-1 phosphorylation at Tyr(14) on HG-induced podocyte inflammation response and TLR4 activation, a recombinant plasmid GFP-Cav-1 Y14F with a mutated phosphorylation site of cav-1, was transfected into cultured podocytes. In vivo, curcumin improved histological abnormalities and fibrosis of a diabetic kidney, inhibited renal inflammatory gene expression and reduced cav-1 phosphorylation at Tyr(14) and the expression of TLR4. Pretreatment of podocytes with curcumin reduced HG-stimulated production of proinflammatory cytokines, TLR4 and the phosphorylation of cav-1. But immunohistochemistry in rat kidney showed that the elevation of TLR4 expression is more evident in the renal interstitum than in the glomerulus where podocytes are located, and the possibility that the anti-inflammatory effects of curcumin on other cells in the kidney may be mediated through the same molecular pathways as in podocytes. Our study suggests that curcumin treatment ameliorates DN via inhibition of inflammatory gene expression by reversing caveolin-1 Tyr(14) phosphorylation that influenced TLR4 activation.
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Preliminary study of neurocognitive dysfunction in adult moyamoya disease and improvement after superficial temporal artery-middle cerebral artery bypass.
J Korean Neurosurg Soc
PUBLISHED: 05-13-2014
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Moyamoya disease (MMD) is a chronic cerebrovascular occlusive disease of unknown etiology. In addition, the neurocognitive impairment of adults with MMD is infrequently reported and, to date, has not been well described. We attempted to determine both the neurocognitive profile of adult moyamoya disease and whether a superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis can improve the neurocognitive impairment in exhibiting hemodynamic disturbance without stroke.
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Novosphingobium chloroacetimidivorans sp. nov., a chloroacetamide herbicide-degrading bacterium isolated from activated sludge.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 05-09-2014
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Strain BUT-14(T), a Gram-reaction-negative, non-spore-forming, ellipse-shaped bacterium, was isolated from activated sludge of a chloroacetamide-herbicides-manufacturing wastewater treatment facility. The strain was able to degrade more than 90% of butachlor, acetochlor and alachlor (100 mg l(-1)) within 5 days of incubation. The taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BUT-14(T) was a member of the genus Novosphingobium and showed the highest sequence similarities to Novosphingobium soli DSM 22821(T) (97.9%), N. naphthalenivorans KACC 15258(T) (97.4%), N. pentaromativorans JCM 12182(T) (97.4%) and N. barchaimii DSM 25411(T) (97.1%) and lower (<97%) sequence similarities to all other species of the genus Novosphingobium. Chemotaxonomic analysis revealed that strain BUT-14(T) possessed Q-10 as the predominant ubiquinone, spermidine as the major polyamine and C(18?:?1)?7c (46.9%), C(17?:?1)?6c (17.9%), summed feature 3, C(14?:?0) 2-OH (4.4%), C(15?:?0) 2-OH (3.1%) and C(16?:?0) (5.51%) as the major fatty acids. The polar lipids included lipid, glycolipid, phosphatidylglycerol, phospholipid, phosphatidylethanolamine, phosphatidylcholine, sphingoglycolipid and phospatidyldimethylethanolamine. Strain BUT-14(T) showed low DNA-DNA relatedness with N. soli DSM 22821(T) (41.5±2.9%), N. naphthalenivorans JCM 12182(T) (49.2±4.2%), N. pentaromativorans KACC 12295(T) (53.2±1.9%) and N. barchaimii DSM 25411 (51.2±4.5%). The DNA G+C content was 66±0.3 mol%. The combination of phylogenetic analysis, phenotypic characteristics, chemotaxonomic data and DNA-DNA hybridization supports the suggestion that strain BUT-14(T) represents a novel species of the genus Novosphingobium, for which the name Novosphingobium chloroacetimidivorans sp. nov. is proposed. The type strain is BUT-14(T) (?=?CCTCC AB 2013086(T)?=?KACC 17147(T)?=?JCM 19923(T)).
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Mapping of hepatic expression quantitative trait loci (eQTLs) in a Han Chinese population.
J. Med. Genet.
PUBLISHED: 03-24-2014
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Elucidating the genetic basis underlying hepatic gene expression variability is of importance to understand the aetiology of the disease and variation in drug metabolism. To date, no genome-wide expression quantitative trait loci (eQTLs) analysis has been conducted in the Han Chinese population, the largest ethnic group in the world.
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Targeted exon sequencing fails to identify rare coding variants with large effect in rheumatoid arthritis.
Arthritis Res. Ther.
PUBLISHED: 03-22-2014
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IntroductionAlthough it has been suggested that rare coding variants could explain the substantial missing heritability, very few sequencing studies have been performed in rheumatoid arthritis (RA). We aimed to identify novel functional variants with rare to low frequency using targeted exon sequencing of RA in Korea.MethodsWe analyzed targeted exon sequencing data of 398 genes selected from a multifaceted approach in Korean RA patients (n¿=¿1,217) and controls (n¿=¿717). We conducted a single-marker association test and a gene-based analysis of rare variants. For meta-analysis or enrichment test, we also used ethnically matched independent samples of Korean genome-wide association studies (GWAS) (n¿=¿4,799) or immunochip data (n¿=¿4,722).ResultsAfter stringent quality control, we analyzed 10,588 variants of 398 genes from 1,934 Korean RA case-controls. We identified 13 non-synonymous variants with nominal association in single variant association tests. In a meta-analysis, we did not find any novel variant with genome-wide significance for RA risk. Using a gene-based approach, we identified 17 genes with nominal burden signals. Among them, VSTM1 showed the greatest association with RA (P¿=¿7.80¿×¿10¿4). In the enrichment test using Korean GWAS, although the significant signal appeared to be driven by total genic variants, we found no evidence for enriched association of coding variants only with RA.ConclusionsWe were unable to identify rare coding variants with large effect to explain the missing heritability for RA in the current targeted resequencing study. Our study raises skepticism about exon sequencing of targeted genes for complex diseases like RA.
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Rebleeding after initial endoscopic hemostasis in peptic ulcer disease.
J. Korean Med. Sci.
PUBLISHED: 03-20-2014
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Endoscopic hemostasis is the first-line treatment for upper gastrointestinal bleeding (UGIB). Although several factors are known to be risk factors for rebleeding, little is known about the use of antithrombotics. We tried to verify whether the use of antithrombotics affects rebleeding rate after a successful endoscopic hemostasis for peptic ulcer disease (PUD). UGIB patients who underwent successful endoscopic hemostasis were included. Rebleeding was diagnosed when the previously treated lesion bled again within 30 days of the initial episode. Of 522 UGIB patients with PUD, rebleeding occurred in 93 patients (17.8%). The rate of rebleeding was higher with aspirin medication (P=0.006) and after a long endoscopic hemostasis (P<0.001). Of all significant variables, procedure time longer than 13.5 min was related to the rate of rebleeding (OR, 2.899; 95% CI, 1.768-4.754; P<0.001) on the logistic regression analysis. The rate of rebleeding after endoscopic hemostasis for PUD is higher in the patients after a long endoscopic hemostasis. Endoscopic hemostasis longer than 13.5 min is related to rebleeding after a successful endoscopic hemostasis for PUD.
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Nocardioides soli sp. nov., a carbendazim-degrading bacterium isolated from soil under the long-term application of carbendazim.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 03-20-2014
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The taxonomic status of a carbendazim-degrading strain, mbc-2(T), isolated from soil under the long-term application of carbendazim in China was determined by means of a polyphasic study. The cells were Gram-stain-positive, motile and rod-shaped. Strain mbc-2(T) grew optimally at pH 7.0, 30-35 °C and in the presence of 1% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain mbc-2(T) fell within the genus Nocardioides, forming a coherent cluster with the type strain of Nocardioides hankookensis, with which it exhibited 16S rRNA gene sequence similarity values of 97.9%. The chemotaxonomic properties of strain mbc-2(T) were consistent with those of the genus Nocardioides: the cell-wall peptidoglycan type was based on ll-2,6-diaminopimelic acid, the predominant menaquinone was MK-8 (H4) and the major fatty acid was iso-C(16?:?0). The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, unknown phospholipids and an unknown aminolipid. The DNA G+C content was 72 mol%. Strain mbc-2(T) exhibited DNA-DNA relatedness values of 12.5±1.5%, 23.7±2.7% and 26.3±3.2% with respect to Nocardioides hankookensis DS-30(T), Nocardioides aquiterrae GW-9(T) and Nocardioides pyridinolyticus OS4(T). On the basis of the data obtained, strain mbc-2(T) represents a novel species of the genus Nocardioides, for which the name Nocardioides soli sp. nov. is proposed. The type strain is mbc-2(T) (?=?KACC 17152(T)?=?CCTCC AB 2012934(T)).
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A phase 1 clinical trial of vorinostat in combination with decitabine in patients with acute myeloid leukaemia or myelodysplastic syndrome.
Br. J. Haematol.
PUBLISHED: 03-19-2014
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Patients with acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS) may respond to treatment with epigenetic-modifying agents. Histone deacetylase inhibitors may synergize with hypomethylating agents. This phase 1 dose-escalation study was designed to determine the maximum tolerated dose, recommended phase 2 dose, safety and tolerability of vorinostat plus decitabine in patients with relapsed/refractory AML, newly-diagnosed AML, or intermediate- to high-grade MDS. Thirty-four patients received concurrent therapy with decitabine plus vorinostat and 37 received sequential therapy with decitabine followed by vorinostat. Twenty-nine patients had relapsed/refractory AML, 31 had untreated AML and 11 had MDS. The target maximum administered dose (MAD) of decitabine 20 mg/m(2) daily for 5 d plus vorinostat 400 mg/d for 14 d was achieved for concurrent and sequential schedules, with one dose-limiting toxicity (Grade 3 QTc prolongation) reported in the sequential arm. Common toxicities were haematological and gastrointestinal. Responses were observed more frequently at the MAD on the concurrent schedule compared with the sequential schedule in untreated AML (46% vs. 14%), relapsed/refractory AML (15% vs. 0%) and MDS (60% vs. 0%). Decitabine plus vorinostat given concurrently or sequentially appears to be safe and well-tolerated. Concurrent therapy shows promising clinical activity in AML or MDS, warranting further investigation.
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Combining the serum pepsinogen level and Helicobacter pylori antibody test for predicting the histology of gastric neoplasm.
J Dig Dis
PUBLISHED: 03-08-2014
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To determine whether the combination test of serum pepsinogen (PG) levels and Helicobacter pylori (H. pylori) antibody was effective for predicting the incidence and histology of gastric neoplasms.
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[Immunomodulatory effect of UC-MSC on function of immunocytes of rats with collagen type II induced arthritis].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 03-07-2014
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This study was purposed to observe the influence of umbilical cord mesenchymal stem cells (UC-MSC) on the peripheral blood CD4(+)CD25(+)regulatory T cells (Treg), Th17 cells and neutrophils in rats with collagen type II-induced arthritis(CIA), and to explore the regulating effect of UC-MSC transplantation on immunocyte subgroup. The rats wee divided into 3 groups: CIA group (model group), UC-MSC treated group and blank control group. The CIA rats were injected with UC-MSC via tail vein. The percentage of CD4(+)CD25(+) cells in peripheral blood and the expression of NCD11b on neutrophil surface in CIA rates was detected by flow cytometry (FCM), and the serum interleukin-17 (IL-17) was observed by enzyme-linked immunosorbent assay (ELISA). The results showed that the mean fluorescence intensity(MFI) of NCD11b and the level of IL-17 in the model group were significantly higher than those in the blank control group, and the ratio of CD4(+)CD25(+) cells were significantly lower (P < 0.05). The MIF of NCD11b and the level of IL-17 in the UC-MSC treated group were significantly lower than that in the model group (P < 0.05), while the proportion of CD4(+)CD25(+) Treg increased (P < 0.05). Since the fifth week, the above indicators in the UC-MSC group have almostly approached the control group. It is concluded that the UC-MSC can increase peripheral blood Treg proportion in CIA rat, inhibit the secretion of Th17 and the activity of neutrophils, reduce the immune inflammation reaction, decrease the release of proinflammatory factor, and induce immune reconstruction.
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Nutlin-3 induces BCL2A1 expression by activating ELK1 through the mitochondrial p53-ROS-ERK1/2 pathway.
Int. J. Oncol.
PUBLISHED: 03-04-2014
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Nutlin-3 which occupies the p53 binding pocket in HDM2, has been reported to activate apoptosis through both the transcriptional activity-dependent and -independent programs of p53. Transcription-independent apoptosis by nutlin-3 is triggered by p53 which is translocated to mitochondria. However, we previously demonstrated that the nutlin-3-induced mitochondrial translocation of p53 stimulates ERK1/2 activation, an anti-apoptosis signal, via mitochondrial ROS generation. We report on how nutlin-3-stimulated ERK1/2 activity inhibits p53-induced apoptosis. Among the anti-apoptotic BCL2 family proteins, BCL2A1 expression was increased by nutlin-3 at both the mRNA and protein levels, and this increase was prevented by the inhibition of ERK1/2. TEMPO, a ROS scavenger, and PFT-? , a blocker of the mitochondrial translocation of p53, also inhibited BCL2A1 expression as well as ERK1/2 phosphorylation. In addition, nutlin-3 stimulated phosphorylation of ELK1, which was prevented by all compounds that inhibited nutlin-3-induced ERK1/2 such as U0126, PFT-? and TEMPO. Moreover, an increase in BCL2A1 expression was weakened by the knockdown of ELK1. Finally, nutlin-3-induced apoptosis was found to be potentiated by the knockdown of BCL2A1, as demonstrated by an increase of in hypo-diploidic cells and Annexin V-positive cells. Parallel to the increase in apoptotic cells, the knockdown of BCL2A1 augmented the cleavage of poly(ADP-ribose) polymerase-1. It is noteworthy that the augmented levels of apoptosis induced by the knockdown of BCL2A1 were comparable to those of apoptosis induced by U0126. Collectively, these results suggest that nutlin-3-activated ERK1/2 may stimulate the transcription of BCL2A1 via the activation of ELK1, and BCL2A1 expression may contribute to the inhibitory effect of ERK1/2 on nutlin-3-induced apoptosis, thereby constituting a negative feedback loop of p53-induced apoptosis.
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Xenophilus arseniciresistens sp. nov., an arsenite-resistant bacterium isolated from soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 02-28-2014
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A Gram-reaction-negative, aerobic, motile, rod-shaped, arsenite [As(III)]-resistant bacterium, designated strain YW8(T), was isolated from agricultural soil. 16S rRNA gene sequence analysis showed over 97% sequence similarity to strains of the environmental species Xenophilus azovorans, Xenophilus aerolatus, Simplicispira metamorpha, Variovorax soli, and Xylophilus ampelinus. However, the phylogenetic tree indicated that strain YW8(T) formed a separate clade from Xenophilus azovorans. DNA-DNA hybridization experiments showed that the DNA-DNA relatedness values between strain YW8(T) and its closest phylogenetic neighbours were below 24.2-35.5%, which clearly separated the strain from these closely related species. The major cellular fatty acids of strain YW8(T) were C(16?:?0), C(17?:?0) cyclo, C(18?:?1)?7c, and summed feature 3(C(16?:?1)?6c and/or C(16?:?1)?7c). The genomic DNA G+C content was 69.3 mol%, and the major respiratory quinone was ubiquinone-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unknown phospholipids, an unknown polar lipid and phosphatidylserine. The major polyamines were 2-hydroxyputrescine and putrescine. On the basis of morphological, physiological and biochemical characteristics, phylogenetic position, DNA-DNA hybridization and chemotaxonomic data, strain YW8(T) is considered to represent a novel species of the genus Xenophilus, for which the name Xenophilus arseniciresistens sp. nov. is proposed; the type strain is YW8(T) (?=?CCTCC AB2012103(T)?=?KACC 16853(T)).
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Arabidopsis HRE1?, a splicing variant of AtERF73/HRE1, functions as a nuclear transcription activator in hypoxia response and root development.
Plant Cell Rep.
PUBLISHED: 02-17-2014
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HRE1? shows transcriptional activation activity in its C-terminal region via GCC box but not DRE/CRT and plays an important role in root development via root meristem cell division regulation. AtERF73/HRE1 protein, a member of the Arabidopsis AP2/ERF family, contains a conserved AP2/ERF DNA-binding domain. Here, we studied the molecular function of HRE1?, a splicing variant of AtERF73/HRE1, as well as its role in root development. HRE1?-overexpressing transgenic plants (OXs) showed tolerance to submergence. HRE1? showed transcriptional activation activity via GCC box but not DRE/CRT. The 121-211 aa region of HRE1? was responsible for the transcriptional activation activity, and the region was conserved among homologs of other species but was not found in other Arabidopsis proteins. HRE1? OXs showed increased primary root length due to elevated root cell division. Our results suggest that HRE1? functions as a transcription activator in the nucleus, and plays an important role in root development through regulation of root meristem cell division.
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The effect of preceding biopsy on complete endoscopic resection in rectal carcinoid tumor.
J. Korean Med. Sci.
PUBLISHED: 02-14-2014
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Biopsy of rectal carcinoid tumor is commonly taken before endoscopic resection. However the preceding biopsy can inhibit complete resection by causing blurred tumor border and fibrosis of the tissue. The objective of the study was to investigate the effect of preceding biopsy on complete endoscopic resection in rectal carcinoid tumor. It was also determined if rectal carcinoid tumors can be macroscopically distinguished by endoscopy. We reviewed retrospectively the records of patients with rectal carcinoid tumor who had undergone an endoscopic treatment at our hospital, during a 7-yr period. The resection margin was clear in 57 of 98 cases. The preceding biopsy was taken in 57 cases and the biopsy was significantly associated with the risk of incomplete tumor resection (OR, 3.696; 95% CI, 1.528-8.938, P = 0.004). In 95.9% of the cases, it was possible to suspect a carcinoid tumor by macroscopic appearance during initial endoscopy. The preceding biopsy may disturb complete resection of rectal carcinoid tumor. In most cases, the carcinoid tumor could be suspected by macroscopic appearance. Therefore the preceding biopsy is not essential, and it may be avoided for the complete resection.
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A case of endovascular treatment for followed by side to side bypass for vertebral artery dissecting aneurysms involved posterior inferior cerebellar artery.
J Korean Neurosurg Soc
PUBLISHED: 01-31-2014
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Treatment of complex aneurysms usually entails not only direct clipping but also alternative treatment modality. We recently experienced a case of vertebral artery dissecting aneurysm and obtained good treatment outcomes. Our case suggests that the endovascular segmental occlusion with posterior inferior cerebellar artery (PICA) to PICA side anastomosis might be a good treatment option in patients with complex vertebral artery dissecting aneurysms. A 45-year-old woman has a left vertebral dissecting aneurysm with dizziness. Based on the aneurysmal morphology and the involvement of PICA, the patient underwent side to side anastomosis of the PICA. This was followed by the endovascular segmental coil occlusion. The aneurysmal sac was completely obliterated. At a 2-year follow-up, the patient achieved a good patency of both PICA. In conclusion our case suggests that the endovascular segmental occlusion of the parent artery followed by PICA to PICA bypass surgery through a midline suboccipital approach is a reasonable multimodal treatment option in patients with complex vertebral artery dissecting aneurysms.
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Effect of pronase premedication on narrow-band imaging endoscopy in patients with precancerous conditions of stomach.
Dig. Dis. Sci.
PUBLISHED: 01-28-2014
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Narrow-band imaging (NBI) endoscopy improves the detection of intestinal metaplasia. However, strategies to improve the visibility and diagnostic performance of NBI should be sought, as endoscopic views are often obscured by the presence of mucus.
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Early prediction of long-term response to cabergoline in patients with macroprolactinomas.
Endocrinol Metab (Seoul)
PUBLISHED: 01-21-2014
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Cabergoline is typically effective for treating prolactinomas; however, some patients display cabergoline resistance, and the early characteristics of these patients remain unclear. We analyzed early indicators predicting long-term response to cabergoline.
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Transdifferentiation of differentiated ovary into functional testis by long-term treatment of aromatase inhibitor in Nile tilapia.
Endocrinology
PUBLISHED: 01-17-2014
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Females with differentiated ovary of a gonochoristic fish, Nile tilapia, were masculinized by long-term treatment with an aromatase inhibitor (Fadrozole) in the present study. The reversed gonads developed into functional testes with fertile sperm. The longer the fish experienced sex differentiation, the longer treatment time was needed for successful sex reversal. Furthermore, Fadrozole-induced sex reversal, designated as secondary sex reversal (SSR), was successfully rescued by supplement of exogenous 17?-estradiol. Gonadal histology, immunohistochemistry, transcriptome, and serum steroid level were analyzed during SSR. The results indicated that spermatogonia were transformed from oogonia or germline stem cell-like cells distributed in germinal epithelium, whereas Leydig and Sertoli cells probably came from the interstitial cells and granulosa cells of the ovarian tissue, respectively. The transdifferentiation of somatic cells, as indicated by the appearance of doublesex- and Mab-3-related transcription factor 1 (pre-Sertoli cells) and cytochrome P450, family 11, subfamily B, polypeptide 2 (pre-Leydig cells)-positive cells in the ovary, provided microniche for the transdifferentiation of germ cells. Decrease of serum 17?-estradiol was detected earlier than increase of serum 11-ketotestosterone, indicating that decrease of estrogen was the cause, whereas increase of androgen was the consequence of SSR. The sex-reversed gonad displayed more similarity in morphology and histology with a testis, whereas the global gene expression profiles remained closer to the female control. Detailed analysis indicated that transdifferentiation was driven by suppression of female pathway genes and activation of male pathway genes. In short, SSR provides a good model for study of sex reversal in teleosts and for understanding of sex determination and differentiation in nonmammalian vertebrates.
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Synthesis of highly luminescent and biocompatible CdTe/CdS/ZnS quantum dots using microwave irradiation: a comparative study of different ligands.
Luminescence
PUBLISHED: 01-16-2014
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We compared the effects of several ligands frequently used in aqueous synthesis, including L-cysteine, L-cysteine hydrochloride, N-acetyl-L-cysteine (NAC), glutathione and 3-mercaptopropionic acid, for microwave synthesis of CdTe quantum dots (QDs) in a sealed vessel with varied temperatures and times, and then developed a rapid microwave-assisted protocol for preparing highly luminescent, photostable and biocompatible CdTe/CdS/ZnS core-multishell QDs. The effects of molecular structures of these ligands on QD synthesis under high temperatures were explored. Among these ligands, NAC was found to be the optimal ligand in terms of the optical properties of resultant QDs and reaction conditions. The emission wavelength of NAC-capped CdTe QDs could reach 700?nm in 5?min by controlling the reaction temperature, and the resultant CdTe/CdS/ZnS core-multishell QDs could achieve the highest quantum yields up to 74% with robust photostability. In addition, the effects of temperature, growth time and shell-precursor ratio on shell growth were examined. Finally, cell culturing indicated the low cytotoxicity of CdTe/CdS/ZnS core-multishell QDs as compared to CdTe and CdTe/CdS QDs, suggesting their high potential for applications in biomedical imaging and diagnostics. Copyright © 2014 John Wiley & Sons, Ltd.
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The Arabidopsis chloroplast protein S-RBP11 is involved in oxidative and salt stress responses.
Plant Cell Rep.
PUBLISHED: 01-11-2014
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S-RBP11, a chloroplast protein, which was isolated using activation tagging system, is shown to be the first Arabidopsis small RNA-binding group protein involved in oxidative and salt stress responses. Activation tagging is one of the most powerful tools in reverse genetics. In this study, we isolated S-RBP11, encoding a small RNA-binding protein in Arabidopsis, by salt-resistant activation tagging line screen and then characterized its function in the abiotic stress response. The isolated activation tagging line of S-RBP11 as well as transgenic plants overexpressing S-RBP11 showed increased tolerance to salt and MV stresses compared to WT plants, whereas s-rbp11 mutants were more sensitive to salt stresses. Transcription of S-RBP11 was elevated upon MV treatment but not NaCl or cold treatment. Interestingly, S-RBP11 protein was localized in the chloroplast and the N-terminal 34 amino acid region of S-RBP11 was necessary for its chloroplast targeting. Our results suggest that S-RBP11 is a chloroplast protein involved in the responses to salt and oxidative stresses.
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Characteristics of toxic metal accumulation in farmland in relation to long-term chicken manure application: a case study in the Yangtze River Delta Region, China.
Bull Environ Contam Toxicol
PUBLISHED: 01-10-2014
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Characteristics of toxic metal accumulation in farmland in relation to intensive chicken manure application on a regional scale was studied in this paper. Concentrations of Zn, As and Cu in manure exceeded the related standard in 66.7%, 14.3% and 16.7% of samples, respectively. Among chicken feed samples, concentrations of Zn, Cr and As exceeded the National Standard limits in 74.3%, 56.3% and 34.3% of samples, respectively. The accumulation of metals in soils from long-term chicken manure application has led to increasing uptake in above-ground shoots of wheat. The maximum contents of all metals present in the soil are currently below the threshold values of National Grade II criteria. At present, the farmland soil is safe for agricultural production, but more attention should be given to the potential environmental risk of metal accumulation in chicken manure and soils.
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Roseomonas rhizosphaerae sp. nov., a triazophos-degrading bacterium isolated from soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 01-09-2014
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A novel aerobic, non-spore-forming, non-motile, catalase- and oxidase-positive, Gram-stain-negative, coccoid to short-rod-shaped bacterial strain, designated YW11(T), was isolated from soil under long-term application of triazophos. The strain was able to hydrolyse triazophos. Strain YW11(T) grew at 15-40 °C (optimum at 28 °C), at pH 5.0-8.0 (optimum at pH 7.5) and with 0-5.0?% (w/v) NaCl (optimum at 0.5?%). The major respiratory quinone was ubiquinone 10 (Q-10) and the major cellular fatty acids were C18?:?1?7c, C16?:?0, C18?:?1 2-OH and C18?:?0. The genomic DNA G+C content of strain YW11(T) was 69.6±0.5 mol%. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, an unknown glycolipid and two unknown aminolipids. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain YW11(T) was a member of the genus Roseomonas, and showed the highest sequence similarity to Roseomonas cervicalis KACC 11686(T) (97.9?%) and Roseomonas aestuarii KACC 19645(T) (97.8?%) and then to Roseomonas ludipueritiae KACC 13843(T) (96.9?%). Strain YW11(T) showed low DNA-DNA relatedness with R. cervicalis KACC 11686(T) (32.3±2.9?%), R. aestuarii KACC 16549(T) (28.2±2.6?%) and R. ludipueritiae KACC 13843(T) (30.2±2.6?%). Based on the results of phylogenetic analysis and DNA-DNA hybridization, the whole-cell fatty acid composition as well as biochemical characteristics, strain YW11(T) was clearly distinguished from all recognized species of the genus Roseomonas and should be assigned to a novel species of the genus Roseomonas, for which the name Roseomonas rhizosphaerae sp. nov. is proposed. The type strain is YW11(T) (?=?KACC 17225(T)?=?CCTCC AB2013041(T)).
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Biophysical and molecular-dynamics studies of phosphatidic acid binding by the Dvl-2 DEP domain.
Biophys. J.
PUBLISHED: 01-08-2014
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The Wnt-dependent, ?-catenin-independent pathway modulates cell movement and behavior. A downstream regulator of this signaling pathway is Dishevelled (Dvl), which, among other multiple interactions, binds to the Frizzled receptor and the plasma membrane via phosphatidic acid (PA) in a mechanism proposed to be pH-dependent. While the Dvl DEP domain is central to the ?-catenin-independent Wnt signaling function, the mechanism underlying its physical interaction with the membrane remains elusive. In this report, we elucidate the structural and functional basis of PA association to the Dvl2 DEP domain. Nuclear magnetic resonance, molecular-dynamics simulations, and mutagenesis data indicated that the domain interacted with the phospholipid through the basic helix 3 and a contiguous loop with moderate affinity. The association suggested that PA binding promoted local conformational changes in helix 2 and ?-strand 4, both of which are compromised to maintain a stable hydrophobic core in the DEP domain. We also show that the Dvl2 DEP domain bound PA in a pH-dependent manner in a mechanism that resembles deprotonation of PA. Collectively, our results structurally define the PA-binding properties of the Dvl2 DEP domain, which can be exploited for the investigation of binding mechanisms of other DEP domain-interacting proteins.
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Current progress toward eradicating Helicobacter pylori in East Asian countries: differences in the 2013 revised guidelines between China, Japan, and South Korea.
World J. Gastroenterol.
PUBLISHED: 01-06-2014
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New 2013 guidelines on Helicobacter pylori (H. pylori) infection have been published in China, Japan, and South Korea. Like the previous ones, these new guidelines differ between the three countries with regard to the indications for H. pylori eradication, diagnostic methods, and treatment regimens. The most profound change among all of the guidelines is that the Japanese national health insurance system now covers the expenses for all infected subjects up to second-line treatment. This makes the Japanese indications for eradication much wider than those in China and South Korea. With regard to the diagnosis, a serum H. pylori antibody test is not recommended in China, whereas it is considered to be the most reliable method in Japan. A decrease relative to the initial antibody titer of more than 50% after 6-12 mo is considered to be the most accurate method for determining successful eradication in Japan. In contrast, only the urea breath test is recommended after eradication in China, while either noninvasive or invasive methods (except the bacterial culture) are recommended in South Korea. Due to the increased rate of antibiotics resistance, first-line treatment is omitted in China and South Korea in cases of clarithromycin resistance. Notably, the Japanese regimen consists of a lower dose of antibiotics for a shorter duration (7 d) than in the other countries. There is neither 14 d nor bismuth-based regimen in the first-line and second-line treatment in Japan. Such differences among countries might be due to differences in the approvals granted by the governments and national health insurance system in each country. Further studies are required to achieve the best results in the diagnosis and treatment of H. pylori infection based on cost-effectiveness in East Asian countries.
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Copper-sulfenate complex from oxidation of a cavity mutant of Pseudomonas aeruginosa azurin.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-03-2014
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Metal-sulfenate centers are known to play important roles in biology and yet only limited examples are known due to their instability and high reactivity. Herein we report a copper-sulfenate complex characterized in a protein environment, formed at the active site of a cavity mutant of an electron transfer protein, type 1 blue copper azurin. Reaction of hydrogen peroxide with Cu(I)-M121G azurin resulted in a species with strong visible absorptions at 350 and 452 nm and a relatively low electron paramagnetic resonance gz value of 2.169 in comparison with other normal type 2 copper centers. The presence of a side-on copper-sulfenate species is supported by resonance Raman spectroscopy, electrospray mass spectrometry using isotopically enriched hydrogen peroxide, and density functional theory calculations correlated to the experimental data. In contrast, the reaction with Cu(II)-M121G or Zn(II)-M121G azurin under the same conditions did not result in Cys oxidation or copper-sulfenate formation. Structural and computational studies strongly suggest that the secondary coordination sphere noncovalent interactions are critical in stabilizing this highly reactive species, which can further react with oxygen to form a sulfinate and then a sulfonate species, as demonstrated by mass spectrometry. Engineering the electron transfer protein azurin into an active copper enzyme that forms a copper-sulfenate center and demonstrating the importance of noncovalent secondary sphere interactions in stabilizing it constitute important contributions toward the understanding of metal-sulfenate species in biological systems.
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Associations between methylenetetrahydrofolate reductase polymorphisms and hepatocellular carcinoma risk in Chinese population.
Tumour Biol.
PUBLISHED: 01-03-2014
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Genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene are considered to have some influence on both folate metabolism and cancer risk. Previous studies on the associations of MTHFR genetic polymorphisms with hepatocellular carcinoma (HCC) risk in Chinese population reported inconsistent results. We performed this meta-analysis to comprehensively assess the associations. Finally, 12 individual case-control studies were included into the meta-analysis. There were seven studies (6,384 subjects) on the MTHFR C677T polymorphism and five studies (4,502 subjects) on the MTHFR A1298C polymorphism. Overall, MTHFR C677T polymorphism was significantly associated with susceptibility to HCC in Chinese population (T versus C, odds ratio (OR)?=?1.09, 95 % confidence interval (95% CI) 1.01-1.17; TT versus CC, OR?=?1.17, 95% CI 1.00-1.38; TT/CT versus CC, OR?=?1.12, 95% CI 1.00-1.26). MTHFR A1298C polymorphism was conversely associated with HCC risk in Chinese population (CC versus AA, OR?=?0.65, 95% CI 0.46-0.91; CC versus AA/AC, OR?=?0.64, 95% CI 0.46-0.90). The sensitivity analysis confirmed the reliability and stability of the meta-analysis. Thus, the findings from our meta-analysis support the associations of MTHFR C677T and A1298C polymorphisms with HCC risk in Chinese population.
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Frequency and Fitness Consequences of Bacteriophage ?6 Host Range Mutations.
PLoS ONE
PUBLISHED: 01-01-2014
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Viruses readily mutate and gain the ability to infect novel hosts, but few data are available regarding the number of possible host range-expanding mutations allowing infection of any given novel host, and the fitness consequences of these mutations on original and novel hosts. To gain insight into the process of host range expansion, we isolated and sequenced 69 independent mutants of the dsRNA bacteriophage ?6 able to infect the novel host, Pseudomonas pseudoalcaligenes. In total, we found at least 17 unique suites of mutations among these 69 mutants. We assayed fitness for 13 of 17 mutant genotypes on P. pseudoalcaligenes and the standard laboratory host, P. phaseolicola. Mutants exhibited significantly lower fitnesses on P. pseudoalcaligenes compared to P. phaseolicola. Furthermore, 12 of the 13 assayed mutants showed reduced fitness on P. phaseolicola compared to wildtype ?6, confirming the prevalence of antagonistic pleiotropy during host range expansion. Further experiments revealed that the mechanistic basis of these fitness differences was likely variation in host attachment ability. In addition, using computational protein modeling, we show that host-range expanding mutations occurred in hotspots on the surface of the phage's host attachment protein opposite a putative hydrophobic anchoring domain.
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Berberine Improves Kidney Function in Diabetic Mice via AMPK Activation.
PLoS ONE
PUBLISHED: 01-01-2014
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Diabetic nephropathy is a major cause of morbidity and mortality in diabetic patients. Effective therapies to prevent the development of this disease are required. Berberine (BBR) has several preventive effects on diabetes and its complications. However, the molecular mechanism of BBR on kidney function in diabetes is not well defined. Here, we reported that activation of AMP-activated protein kinase (AMPK) is required for BBR-induced improvement of kidney function in vivo. AMPK phosphorylation and activity, productions of reactive oxygen species (ROS), kidney function including serum blood urea nitrogen (BUN), creatinine clearance (Ccr), and urinary protein excretion, morphology of glomerulus were determined in vitro or in vivo. Exposure of cultured human glomerulus mesangial cells (HGMCs) to BBR time- or dose-dependently activates AMPK by increasing the thr172 phosphorylation and its activities. Inhibition of LKB1 by siRNA or mutant abolished BBR-induced AMPK activation. Incubation of cells with high glucose (HG, 30 mM) markedly induced the oxidative stress of HGMCs, which were abolished by 5-aminoimidazole-4-carboxamide ribonucleoside, AMPK gene overexpression or BBR. Importantly, the effects induced by BBR were bypassed by AMPK siRNA transfection in HG-treated HGMCs. In animal studies, streptozotocin-induced hyperglycemia dramatically promoted glomerulosclerosis and impaired kidney function by increasing serum BUN, urinary protein excretion, and decreasing Ccr, as well as increased oxidative stress. Administration of BBR remarkably improved kidney function in wildtype mice but not in AMPK?2-deficient mice. We conclude that AMPK activation is required for BBR to improve kidney function in diabetic mice.
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[Curative effects on standardized management of community patients with coronary heart disease complicated with chronic heart failure].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 12-05-2013
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To explore the effects on the standardized management of patients with coronary atherosclerotic heart disease complicated with chronic heart failure.
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Age-stage two-sex life tables of Panonychus ulmi (Acari: Tetranychidae), on different apple varieties.
J. Econ. Entomol.
PUBLISHED: 11-15-2013
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To understand the influence of different apple varieties on the development and reproduction of the European red mite, Panonychus ulmi (Koch) (Acari: Tetranychidae), age-stage two-sex life tables of P. ulmi on Fuji, Starkrimson Delicious, Golden Delicious, and Granny Smith varieties were constructed under laboratory conditions at 23 +/- 1 degrees C, 75 +/- 5% relative humidity, and a photoperiod of 16:8 (L:D) h. Results showed that total development time of immature females was shorter on Fuji than on the other varieties, and this was because of its shorter egg duration. Immature survival of P. ulmi was 74.51-78.00% among four apple varieties, and no significant differences were found. The total fecundity per female was significantly higher on Golden Delicious (34.12 eggs per female) than that on Fuji (27.15 eggs per female), Starkrimson Delicious (25.15 eggs per female), and Granny Smith (20.62 eggs per female). Based on the intrinsic rate of population increase, Fuji and Golden Delicious were more suitable than Starkrimson Delicious and Granny Smith.
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On the maximal size of large-average and ANOVA-fit submatrices in a Gaussian random matrix.
Bernoulli (Andover)
PUBLISHED: 11-07-2013
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We investigate the maximal size of distinguished submatrices of a Gaussian random matrix. Of interest are submatrices whose entries have an average greater than or equal to a positive constant, and submatrices whose entries are well fit by a two-way ANOVA model. We identify size thresholds and associated (asymptotic) probability bounds for both large-average and ANOVA-fit submatrices. Probability bounds are obtained when the matrix and submatrices of interest are square and, in rectangular cases, when the matrix and submatrices of interest have fixed aspect ratios. Our principal result is an almost sure interval concentration result for the size of large average submatrices in the square case.
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[Host preference and fitness of aphis citricola (Hemiptera: Aphididae) to mature and young apple leaves].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 11-02-2013
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In order to understand the differences of Aphis citricola in its original and final selectivity to the apple leaves with different leaf age, and to ascertain the effects of mature and young apple leaves on the growth and development, survival, and fecundity of A. citricola, this paper studied the host preference of A. citricola to mature and young apple leaves, with the related age-stage two-type life tables constructed. A. citricola more preferred to oviposit on the young leaves. There existed differences in the behaviors between oriented selectivity and penetration selectivity, and the latter was the key factor determining whether A. citricola fed and oviposited on the host. The total development time of immature A. citricola on the mature leaves was significantly longer than that on the young leaves, and the survival rate was also lower, with the aphids died at the first and fourth instar stages and at mature stage. As compared with those on the young leaves, the apterae rate of A. citricola adults on the mature leaves was lower, and the longevity and fecundity were significantly shorter and lower. The population dynamic parameters suggested that the population growth of A. citricola was quicker on the young leaves than on the mature leaves, and it was difficult for A. citricola to establish a stable population on the mature leaves.
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[Cytomegalovirus jejunitis diagnosed with single-balloon enteroscopy].
Korean J Gastroenterol
PUBLISHED: 10-29-2013
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Cytomegalovirus (CMV) infections are usually diagnosed in immunocompromised patients. A 74-year-old male without any significant medical history visited our center because of abdominal pain and diarrhea which began about a month ago. Abdominal computed tomography revealed segmental enhanced bowel wall thickening on jejunum and single-balloon enteroscopy showed multiple geographic shaped ulcerations covered with exudates on proximal jejunum. Biopsy samples taken during endoscopic examination demonstrated necrotic fibrinopurulent tissue debris and benign ulcer. Nested-PCR analysis of CMV DNA from jejunal tissue was positive. The patient was finally diagnosed with CMV jejunitis and was treated by intravenous ganciclovir for 14 days after which, abdominal pain and diarrhea improved. Our case shows that CMV jejunitis can occur in an immunocompetent adult as multiple jejunal ulcers which can be diagnosed using a single-balloon enteroscope.
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Antagonistic Roles of Dmrt1 and Foxl2 in Sex Differentiation via Estrogen Production in Tilapia as Demonstrated by TALENs.
Endocrinology
PUBLISHED: 10-08-2013
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Transcription activator-like effector nucleases (TALENs) are a powerful approach for targeted genome editing and have been proved to be effective in several organisms. In this study, we reported that TALENs can induce somatic mutations in Nile tilapia, an important species for worldwide aquaculture, with reliably high efficiency. Six pairs of TALENs were constructed to target genes related to sex differentiation, including dmrt1, foxl2, cyp19a1a, gsdf, igf3, and nrob1b, and all resulted in indel mutations with maximum efficiencies of up to 81% at the targeted loci. Effects of dmrt1 and foxl2 mutation on gonadal phenotype, sex differentiation, and related gene expression were analyzed by histology, immunohistochemistry, and real-time PCR. In Dmrt1-deficient testes, phenotypes of significant testicular regression, including deformed efferent ducts, degenerated spermatogonia or even a complete loss of germ cells, and proliferation of steroidogenic cells, were observed. In addition, disruption of Dmrt1 in XY fish resulted in increased foxl2 and cyp19a1a expression and serum estradiol-17? and 11-ketotestosterone levels. On the contrary, deficiency of Foxl2 in XX fish exhibited varying degrees of oocyte degeneration and significantly decreased aromatase gene expression and serum estradiol-17? levels. Some Foxl2-deficient fish even exhibited complete sex reversal with high expression of Dmrt1 and Cyp11b2. Furthermore, disruption of Cyp19a1a in XX fish led to partial sex reversal with Dmrt1 and Cyp11b2 expression. Taken together, our data demonstrated that TALENs are an effective tool for targeted gene editing in tilapia genome. Foxl2 and Dmrt1 play antagonistic roles in sex differentiation in Nile tilapia via regulating cyp19a1a expression and estrogen production.
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Nutlin-3 induces HO-1 expression by activating JNK in a transcription-independent manner of p53.
Int. J. Oncol.
PUBLISHED: 10-04-2013
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A recent study reported that p53 can induce HO-1 by directly binding to the putative p53 responsive element in the HO-1 promoter. In this study, we report that nutlin-3, a small molecule antagonist of HDM2, induces the transcription of HO-1 in a transcription-independent manner of p53. Nutlin-3 induced HO-1 expression at the level of transcription in human cancer cells such as U2OS and RKO cells. This induction of HO-1 did not occur in SAOS cells in which p53 was mutated and was prevented by knocking down the p53 protein using p53 siRNA transfection, but not by PFT-?, an inhibitor of the transcriptional activity of p53. Accompanying HO-1 expression, nutlin-3 stimulated the accumulation of ROS and the phosphorylation of MAPKs such as JNK, p38 MAPK and ERK1/2. Nutlin-3-induced HO-1 expression was suppressed by TEMPO, a ROS scavenger, and chemical inhibitors of JNK and p38 MAPK but not ERK1/2. In addition, nutlin?3-induced phosphorylation of JNK but not p38 MAPK was inhibited by TEMPO. Notably, the levels of nutlin-3-induced ROS were correlated with the mitochondrial translocation of p53 and this induction was prevented by PFT-?, an inhibitor of the mitochondrial translocation of p53. Consistent with the effect of the ROS scavenger and MAPK inhibitors, PFT-? reduced HO-1 expression and the phosphorylation of JNK induced by nutlin-3. In the experiments of analyzing cell death, the knockdown of HO-1 augmented nutlin-3-induced apoptosis. Collectively, these results suggest that nutlin-3 induces HO-1 expression via the activation of both JNK which is dependent on ROS generated by p53 translocated to the mitochondria and p38 MAPK which appears to be stimulated by a ROS-independent mechanism, and this HO-1 induction may inhibit nutlin-3-induced apoptosis, constituting a negative feedback loop of p53-induced apoptosis.
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Wilms tumor gene 1 enhances nutlin-3-induced apoptosis.
Oncol. Rep.
PUBLISHED: 09-27-2013
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Nutlin-3, a human double minute 2 (HDM2) antagonist, induces cell cycle arrest or apoptosis by upregulating p53 in cancer cells. WT1, the product of Wilms tumor gene 1, has been shown to interact with p53, but the effect of WT1 on nutlin-3-induced apoptosis has yet to be examined. To address this issue, we analyzed the inhibitory effect of nutlin-3 on cell growth as a function of Wt1 expression status using a Wt1-inducible U2OS cell line. In the absence of Wt1 expression, nutlin-3 induced cell cycle arrest with marginal cytotoxicity. Furthermore, upon Wt1 expression, nutlin-3 exerted a marked degree of cell death, as evidenced by the accumulation of hypo-diploid cells and LDH release. During cell death induction, cytochrome c was released into the cytosol, and caspase-9 and -3 were activated, suggesting that an intrinsic apoptotic pathway may be involved in this cell death. Consistent with this, z-VAD-Fmk, a pan-caspase inhibitor and the overexpression of BCL-XL attenuated the cell death. Nutlin-3 caused an increase in the mRNA levels of both BCL-XL and BAK, as well as their corresponding protein levels in mitochondria. In the presence of Wt1, nutlin-3-induced BCL-XL expression was attenuated while the expression of nutlin-3-induced BAK was potentiated. Collectively, these results suggest that WT1 potentiates nutlin-3-induced apoptosis by downregulating the expression of BCL-XL while upregulating that of BAK, which leads to the activation of an intrinsic apoptotic pathway.
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A novel model for orthotopic liver transplantation in rats using hepatic rearterialization and biliary extradrainage system.
J. Surg. Res.
PUBLISHED: 09-01-2013
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Although the rat orthotopic liver transplantation (OLT) model has existed for many years, only a few models can be applied for dynamic bile collection. The aim of this study was to introduce a dependent rat OLT model with hepatic rearterialization and an expediently dynamic bile collection system.
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Organophosphorus pesticides detection using broad-specific single-stranded DNA based fluorescence polarization aptamer assay.
Biosens Bioelectron
PUBLISHED: 08-23-2013
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An approach is developed to detect the organophosphorus pesticides via competitive binding to a recombinant broad-specificity DNA aptamer with a molecular beacon (MB), the binding of the MB to the aptamer results in the activation of a fluorescent signal, which can be measured for pesticide quantification. Aptamers selected via the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) were structurally modified and truncated to narrow down the binding region of the target, which indicated that loops of the aptamer contributed different functions for different chemical recognition. Thereafter, a variant fused by two different minimum functional structures, was clarified with broad specificity and increased affinity. Further molecular docking and molecular dynamics simulations was conducted to understand the molecular interaction between DNA structure and chemicals. 3D modeling revealed a hot spot area formed by 3 binding sites, forces including hydrogen bonds and van der Waals interactions appear to play a significant role in enabling and stabilizing the binding of chemicals. Finally, an engineered aptamer based approach for the detection of organophosphorus pesticides was successfully applied in a test using a real sample, the limit of quantification (LOQ) for phorate, profenofos, isocarbophos, and omethoate reached 19.2, 13.4, 17.2, and 23.4nM (0.005mgL(-1)), respectively.
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A review of statistical issues with progression-free survival as an interval-censored time-to-event endpoint.
J Biopharm Stat
PUBLISHED: 08-21-2013
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Frequent rise of interval-censored time-to-event data in randomized clinical trials (e.g., progression-free survival [PFS] in oncology) challenges statistical researchers in the pharmaceutical industry in various ways. These challenges exist in both trial design and data analysis. Conventional statistical methods treating intervals as fixed points, which are generally practiced by pharmaceutical industry, sometimes yield inferior or even flawed analysis results in extreme cases for interval-censored data. In this article, we examine the limitation of these standard methods under typical clinical trial settings and further review and compare several existing nonparametric likelihood-based methods for interval-censored data, methods that are more sophisticated but robust. Trial design issues involved with interval-censored data comprise another topic to be explored in this article. Unlike right-censored survival data, expected sample size or power for a trial with interval-censored data relies heavily on the parametric distribution of the baseline survival function as well as the frequency of assessments. There can be substantial power loss in trials with interval-censored data if the assessments are very infrequent. Such an additional dependency controverts many fundamental assumptions and principles in conventional survival trial designs, especially the group sequential design (e.g., the concept of information fraction). In this article, we discuss these fundamental changes and available tools to work around their impacts. Although progression-free survival is often used as a discussion point in the article, the general conclusions are equally applicable to other interval-censored time-to-event endpoints.
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Depletion of Aurora A leads to upregulation of FoxO1 to induce cell cycle arrest in hepatocellular carcinoma cells.
Cell Cycle
PUBLISHED: 08-09-2013
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Aurora A kinase has drawn considerable attention as a therapeutic target for cancer therapy. However, the underlying molecular and cellular mechanisms of the anticancer effects of Aurora A kinase inhibition are still not fully understood. Herein, we show that depletion of Aurora A kinase by RNA interference (RNAi) in hepatocellular carcinoma (HCC) cells upregulated FoxO1 in a p53-dependent manner, which induces cell cycle arrest. Introduction of an RNAi-resistant Aurora A kinase into Aurora A-knockdown cells resulted in downregulation of FoxO1 expression and rescued proliferation. In addition, silencing of FoxO1 in Aurora A-knockdown cells allowed the cells to exit cytostatic arrest, which, in turn, led to massive cell death. Our results suggest that FoxO1 is responsible for growth arrest at the G2/M phase that is induced by Aurora A kinase inhibition.
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Two indices affecting the directions of the sylvian fissure dissection in middle cerebral artery bifurcation aneurysms.
J Cerebrovasc Endovasc Neurosurg
PUBLISHED: 07-05-2013
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This study proposes more objective methods for deciding the appropriate direction of the sylvian fissure dissection during surgical clipping in middle cerebral artery (MCA) bifurcation aneurysms.
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The usefulness of the ivy sign on fluid-attenuated intensity recovery images in improved brain hemodynamic changes after superficial temporal artery-middle cerebral artery anastomosis in adult patients with moyamoya disease.
J Korean Neurosurg Soc
PUBLISHED: 06-13-2013
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MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images.
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Regulation of docosahexaenoic acid production by Schizochytrium sp.: effect of nitrogen addition.
Bioprocess Biosyst Eng
PUBLISHED: 06-08-2013
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Docosahexaenoic acid (DHA) percentage in total fatty acids (TFAs) is an important index in DHA microbial production. In this study, the change of DHA percentage in response to fermentation stages and the strategies to increase DHA percentage were investigated. Two kinds of conventional nitrogen sources, monosodium glutamate (MSG) and ammonium sulfate (AS), were tested to regulate DHA synthesis. Results showed that MSG addition could accelerate the substrate consumption rate but inhibit lipid accumulation, while AS addition could increase DHA percentage in TFAs effectively but extend fermentation period slightly. Finally, the AS addition strategy was successfully applied in 7,000-L fermentor and DHA percentage in TFAs and DHA yield reached 46.06 % and 18.48 g/L, which was 19.54 and 17.41 % higher than that of no-addition strategy. This would provide guidance for the large-scale production of the other similar polyunsaturated fatty acid, and give insight into the nitrogen metabolism in oil-producing microorganisms.
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Low Prevalence of Microsatellite Instability in Interval Gastric Cancers.
Dig. Dis. Sci.
PUBLISHED: 05-18-2013
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Esophagogastroduodenoscopy (EGD) is recommended at 2-year intervals in countries with a high prevalence of gastric cancer. The aim of this study was to determine whether interval gastric cancers that develop within 2 years of a previous complete screening are associated with microsatellite instability (MSI).
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Early Gastric Cancer-Like Advanced Gastric Cancer versus Advanced Gastric Cancer-Like Early Gastric Cancer.
Clin Endosc
PUBLISHED: 03-31-2013
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Improvements in the endoscopic evaluation and management of gastric cancer have made it possible to determine the depth of invasion during endoscopic examination. The aim of this study was to elucidate the differences between early gastric cancer (EGC) that resembles advanced gastric cancer (AGC) and AGC that resembles EGC.
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Three-dimensional ZnO@MnO2 core@shell nanostructures for electrochemical energy storage.
Chem. Commun. (Camb.)
PUBLISHED: 03-13-2013
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Three-dimensional (3D) ZnO@MnO2 core@shell branched nanowire arrays exhibit five times higher areal capacitance, better rate performance and smaller inner resistance than their nanowire array counterparts. These novel 3D architectures offer promising designs for powering microelectronics and other autonomous devices on exceptionally small geometric scales.
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Is the proton pump inhibitor test helpful in patients with laryngeal symptoms?
Dig. Dis. Sci.
PUBLISHED: 02-27-2013
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The association of gastroesophageal reflux disease (GERD) and laryngeal symptoms is not clear. We aimed to examine the symptomatic and endoscopic relations between GERD and laryngeal symptoms and also to evaluate the response to a 2-week proton pump inhibitor (PPI) trial.
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Structural basis for interactions of the Phytophthora sojae RxLR effector Avh5 with phosphatidylinositol 3-phosphate and for host cell entry.
Mol. Plant Microbe Interact.
PUBLISHED: 02-07-2013
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Oomycetes such as Phytophthora sojae employ effector proteins that enter plant cells to facilitate infection. Entry of some effector proteins is mediated by RxLR motifs in the effectors and phosphoinositides (PIP) resident in the host plasma membrane such as phosphatidylinositol 3-phosphate (PtdIns(3)P). Recent reports differ regarding the regions on RxLR effectors involved in PIP recognition. We have structurally and functionally characterized the P. sojae effector, avirulence homolog-5 (Avh5). Using nuclear magnetic resonance (NMR) spectroscopy, we demonstrate that Avh5 is helical in nature, with a long N-terminal disordered region. NMR titrations of Avh5 with the PtdIns(3)P head group, inositol 1,3-bisphosphate, directly identified the ligand-binding residues. A C-terminal lysine-rich helical region (helix 2) was the principal lipid-binding site, with the N-terminal RxLR (RFLR) motif playing a more minor role. Mutations in the RFLR motif affected PtdIns(3)P binding, while mutations in the basic helix almost abolished it. Mutations in the RFLR motif or in the basic region both significantly reduced protein entry into plant and human cells. Both regions independently mediated cell entry via a PtdIns(3)P-dependent mechanism. Based on these findings, we propose a model where Avh5 interacts with PtdIns(3)P through its C terminus, and by binding of the RFLR motif, which promotes host cell entry.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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

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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.