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Find video protocols related to scientific articles indexed in Pubmed.
Soluble Diazaiptycenes: Materials for Solution-Processed Organic Electronics.
J. Org. Chem.
PUBLISHED: 11-20-2014
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The synthesis and characterization of soluble azaiptycenes is reported. Optical and physical properties were studied and compared to those of the structurally consanguine azaacenes. Electrochemical experi-ments and quantum chemical calculations revealed the electronic structure of the iptycene derivatives. Their crystallization behavior was examined. A highly fluorescent amorphous diazatetracene derivative was integrated into a simple organic light emitting diode (OLED), showing enhanced performance com-pared to that of earlier reported, structurally similar tetracenes.
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Simultaneous Quantification of Hg(2+) and MeHg(+) in Aqueous Media with a Single Fluorescent Probe by Multiplexing in the Time Domain.
Anal. Chem.
PUBLISHED: 11-18-2014
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Development of a molecular probe for selective detection of MeHg(+) in the presence of Hg(2+) is a mission impossible to accomplish. Speciation analysis of two substrates with a single kinetic trace exploiting their differential reactivity toward a single probe, i.e., multiplexing in the time domain, is a cost-effective and powerful alternative. We have developed such a probe (Hg410) for simultaneously quantification of Hg(2+) and MeHg(+) in aqueous media. Hg410 is designed via the "covalent-assembly" approach, displays a zero background, and bears a very concise molecular construct. It has harnessed proximity-based catalysis to achieve high reactivity toward Hg(2+) and MeHg(+). An unprecedentedly low detection limit of ca. 4.6 pM and 160 pM was measured for Hg(2+) and MeHg(+), respectively.
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Bone Morphogenetic Protein (BMP) signaling in development and human diseases.
Genes Dis
PUBLISHED: 11-18-2014
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Bone Morphogenetic Proteins (BMPs) are a group of signaling molecules that belongs to the Transforming Growth Factor-? (TGF-?) superfamily of proteins. Initially discovered for their ability to induce bone formation, BMPs are now known to play crucial roles in all organ systems. BMPs are important in embryogenesis and development, and also in maintenance of adult tissue homeostasis. Mouse knockout models of various components of the BMP signaling pathway result in embryonic lethality or marked defects, highlighting the essential functions of BMPs. In this review, we first outline the basic aspects of BMP signaling and then focus on genetically manipulated mouse knockout models that have helped elucidate the role of BMPs in development. A significant portion of this review is devoted to the prominent human pathologies associated with dysregulated BMP signaling.
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Brain Volume as an Integrated Marker for the Risk of Death in a Community-Based Sample: Age Gene/Environment Susceptibility-Reykjavik Study.
J. Gerontol. A Biol. Sci. Med. Sci.
PUBLISHED: 11-01-2014
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Total brain volume is an integrated measure of health and may be an independent indicator of mortality risk independent of any one clinical or subclinical disease state. We investigate the association of brain volume to total and cause-specific mortality in a large nondemented stroke-free community-based cohort.
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Green facile scalable synthesis of titania/carbon nanocomposites: new use of old dental resins.
ACS Appl Mater Interfaces
PUBLISHED: 10-30-2014
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A green facile scalable method inspired by polymeric dental restorative composite is developed to synthesize TiO2/carbon nanocomposites for manipulation of the intercalation potential of TiO2 as lithium-ion battery anode. Poorly crystallized TiO2 nanoparticles with average sizes of 4-6 nm are homogeneously embedded in carbon matrix with the TiO2 mass content varied between 28 and 65%. Characteristic discharge/charge plateaus of TiO2 are significantly diminished and voltage continues to change along with proceeding discharge/charge process. The tap density, gravimetric and volumetric capacities, and cyclic and rate performance of the TiO2/C composites are effectively improved.
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Formal [4+2] annulation of enaminones and cyanomethyl sulfur ylide: one-pot access to polysubstituted pyridin-2(1H)-ones.
Chem. Commun. (Camb.)
PUBLISHED: 10-28-2014
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A facile and efficient one-pot synthesis of polysubstituted pyridin-2(1H)-ones from readily available enaminones and the cyanomethyl sulfonium bromide salt in the presence of cesium carbonate is developed, and a mechanism involving sequential nucleophilic vinylic substitution (SNV), intramolecular nucleophilic cyclization and dealkylation reactions is proposed.
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Solution-Processed Organic Solar Cells Based on Dialkylthiol-Substituted Benzodithiophene Unit with Efficiency near 10%.
J. Am. Chem. Soc.
PUBLISHED: 10-27-2014
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A small molecule named DR3TSBDT with dialkylthiol-substituted benzo[1,2-b:4,5-b']dithiophene (BDT) as the central unit was designed and synthesized for solution-processed bulk-heterojunction solar cells. A notable power conversion efficiency of 9.95% (certified 9.938%) has been achieved under AM 1.5G irradiation (100 mW cm(-2)), with an average PCE of 9.60% based on 50 devices.
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Relationship between fine particulate air pollution and ischaemic heart disease morbidity and mortality.
Heart
PUBLISHED: 10-25-2014
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To assess the relationship between fine particulate matter (PM2.5) concentration and ischaemic heart disease (IHD) morbidity and mortality.
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Thermoelectric materials: organic thermoelectric materials: emerging green energy materials converting heat to electricity directly and efficiently (adv. Mater. 40/2014).
Adv. Mater. Weinheim
PUBLISHED: 10-24-2014
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Organic conducting materials display great potential to be efficient thermoelectric materials according to the latest reports. On page 6829, W. Xu, D. B. Zhu and co-workers review thermoelectric and related properties of organic conducting materials, including polymers and small molecules, and highlight the most recent progress in materials, measurements, and devices. Prospects for future research are discussed in pursuit of green energy converted by organic thermoelectric materials.
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DNA methylation: the pivotal interaction between early-life nutrition and glucose metabolism in later life.
Br. J. Nutr.
PUBLISHED: 10-20-2014
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Traditionally, it has been widely acknowledged that genes together with adult lifestyle factors determine the risk of developing some metabolic diseases such as insulin resistance, obesity and diabetes mellitus in later life. However, there is now substantial evidence that prenatal and early-postnatal nutrition play a critical role in determining susceptibility to these diseases in later life. Maternal nutrition has historically been a key determinant for offspring health, and gestation is the critical time window that can affect the growth and development of offspring. The Developmental Origins of Health and Disease (DOHaD) hypothesis proposes that exposures during early life play a critical role in determining the risk of developing metabolic diseases in adulthood. Currently, there are substantial epidemiological studies and experimental animal models that have demonstrated that nutritional disturbances during the critical periods of early-life development can significantly have an impact on the predisposition to developing some metabolic diseases in later life. The hypothesis that epigenetic mechanisms may link imbalanced early-life nutrition with altered disease risk has been widely accepted in recent years. Epigenetics can be defined as the study of heritable changes in gene expression that do not involve alterations in the DNA sequence. Epigenetic processes play a significant role in regulating tissue-specific gene expression, and hence alterations in these processes may induce long-term changes in gene function and metabolism that persist throughout the life course. The present review focuses on how nutrition in early life can alter the epigenome, produce different phenotypes and alter disease susceptibilities, especially for impaired glucose metabolism.
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Influence of Three Coccidiostats on the Pharmacokinetics of Florfenicol in Rabbits.
Exp. Anim.
PUBLISHED: 10-17-2014
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In-feed Medication has been used for a long time to prevent coccidiosis, a worldwide protozoal disease in rabbits. Florfenicol (FFC) has been widely used in veterinary clinics for bacterial diseases treatment. Therefore, the use of combinations of coccidiostats with FFC in rabbits is common. In the present study, we aimed to evaluate the effect of three coccidiostats, sulfaquinoxaline (SUL), robenidine (ROB), and toltrazuril (TOL), as feed additives on the pharmacokinetic profile of FFC in rabbits. The disposition kinetics of FFC in rabbits were investigated after a single intravenous injection (25 mg/kg) in rabbits fed anticoccidial-free diets or feeds containing SUL (250 ppm), ROB (66 ppm), or TOL (2 ppm), respectively, for 20 days. Plasma FFC concentrations were determined by the high performance liquid chromatography (HPLC) method. The pharmacokinetic parameters of FFC were analyzed using a non-compartmental analysis based on the statistical moment theory. The results demonstrated that ROB feeding resulted in an obvious decrease in plasma FFC level as compared with anticoccidial-free feeding. The terminal elimination half-life (t1/2z), area under the concentration-time curve (AUC), area under the first moment curve (AUMC), and mean residence time (MRT) significantly decreased, whereas the elimination rate constant (?z) and total body clearance (CLz) obviously increased in rabbits pretreated with ROB. However, we did not find that SUL or TOL feeding had any effect on the pharmacokinetic profile of FFC. Our findings suggested that more attention should be paid to the use of FFC in rabbits supplemented with ROB.
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Enhanced photoelectrochemical performance by synthesizing CdS decorated reduced TiO2 nanotube arrays.
Phys Chem Chem Phys
PUBLISHED: 09-30-2014
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The efficient utilization of solar spectrum and photo-induced charge transport are critical aspects in improving the light conversion efficiency of solar cells and hydrogen generation. In this work, reduced TiO2 nanotube arrays with CdS decoration were fabricated through the simple cathodic polarization of annealed TiO2 nanotube arrays followed by the chemical deposition of CdS nanoparticles. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy confirmed the successful fabrication of the target material. UV-visible diffuse reflectance spectra showed a Burstein-Moss shift for reduced TiO2 NTs and a red shift of the absorption edge towards ca. 563 nm for CdS-decorated R-TiO2 NTs. Cyclic voltammetry and impedance spectra together demonstrate the decreased charge transport resistance for reduced TiO2 NTs. Under the excitation of monochromatic light at 420 nm, the proposed CdS-decorated reduced TiO2 NTs exhibit the maximum IPCE value of 30.12% in 1 M Na2SO3 electrolyte, which is almost twice higher than that achieved on CdS-decorated pristine TiO2 NTs. Therefore, the results here highlight the significance of charge transport in the light conversion process. The enhanced charge transport properties are ascribed to the increased number of electrons, which is brought about by the lattice oxygen vacancies (Ti(3+)) during the cathodic polarization.
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[Characterization of a recombinant goatpox virus expressing Orfv F1L gene].
Wei Sheng Wu Xue Bao
PUBLISHED: 09-26-2014
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In order to establish the vaccine against the contagious ecthyma, we constructed and characterized recombinant goatpox virus expressing F1L protein of Orf virus.
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[HPLC determination of two phenylpropanoid amides in solani melongenae radix from different cultivation regions].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 09-24-2014
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A quantitative HPLC-DAD method was developed for simultaneous determination of N-trans-p-coumaroyloctopamine and N-trans-p-coumaroyltyramine in Solani Melongenae Radix from different cultivation regions in China The separation was performed on an Agilent Eclipse XDB C18 column (4.6 mm x 250 mm, 5 microm) at 30 degrees C with a gradient elution of methanol and 0.1% formic acid in water as mobile phase. The flow rate was set at 1.0 mL x min(-1) and the detection wavelength was 300 nm. The calibration curves of N-trans-p-coumaroyloctopamine and N-trans-p-coumaroyltyramine were linear over the ranges of 2.84-68.16, 3.10-74.40 mg x L(-1), and the average recoveries (n = 9) were 99.30% and 102.8%, respectively. The developed method was successfully applied for the analysis of sixteen samples from different cultivation regions in China, which indicated that the method is simple, rapid, accurate, and reliable for quality evaluation of Solani Melongenae Radix.
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Anti-inflammatory Ursane- and Oleanane-Type Triterpenoids from Vitex negundo var. cannabifolia.
J. Nat. Prod.
PUBLISHED: 09-23-2014
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Six new polyoxygenated triterpenoids, cannabifolins A-F (1-6), and eight known triterpenoids, 7-14, were isolated from the leaves of Vitex negundo var. cannabifolia. The absolute configuration of cannabifolin A (1) was determined by single-crystal X-ray crystallographic analysis. Compounds 1 and 2 represent a class of rare natural pentacyclic triterpenoids bearing cis-fused C/D rings and are the first examples of 12,19-epoxy ursane- and oleanane-type triterpenoids. Compounds 3, 7, 8, and 14 exhibited inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages with IC50 values in the range 24.9-40.5 ?M.
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Isomeric folate-conjugated polymeric micelles bind to folate receptors and display anticancer effects.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-18-2014
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The present study aimed to prepare and evaluate polymeric micelles conjugated with folic acid through ?- or ?-carboxyl groups for antitumor efficacy. The isomeric block copolymers, ?- and ?-folate-polyethyleneglycol- distearoyl phosphatidylethanolamine (?- and ?-Fol-PEG-DSPE), were produced by solid phase peptide synthesis. Three types of doxorubicin (DOX)-loaded polymeric micelles (MPEG-DSPE-DOX and ?- / ?-Fol-PEG-DSPE- DOX micelles) were prepared via the film formation method. Compared with MPEG-DSPE-DOX micelles, the ?- / ?-Fol-PEG-DSPE-DOX micelles presented a higher cellular uptake behavior in the live cell study. Cell viability percentages were 81.8%, 57.3%, 56.6% at 2 hours for MPEG-DSPE-DOX, ?- and ?-Fol-PEG-DSPE- DOX micelles, respectively (p<0.05). Using the KB xenograft tumor model, both ?- and ?-folate-conjugated micelles were found to have better antitumor effects with lower toxicity in comparison with MPEG-DSPE-DOX micelles. No difference in in vivo antitumor efficacy was found between ?-and ?-Fol-PEG-DSPE-DOX micelles. The folate-conjugated micelles might be a potentially useful strategy for tumor targeting of therapeutic agents, whether grafting with folic acid through ?- or ?-carboxyl groups.
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Selective and Ratiometric Fluorescent Trapping and Quantification of Protein Vicinal Dithiols and in Situ Dynamic Tracing in Living Cells.
J. Am. Chem. Soc.
PUBLISHED: 09-17-2014
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Protein vicinal dithiols play fundamental roles in intracellular redox homeostasis due to their involvement in protein synthesis and function through the reversible vicinal dithiol oxidation to disulfide. To provide quantitative information about the global distribution and dynamic changes of protein vicinal dithiols in living cells, we have designed and synthesized a ratiometric fluorescent probe (VTAF) for trapping of vicinal dithiol-containing proteins (VDPs) in living cells. VTAF exhibits a ratiometric fluorescence signal upon single excitation, which enables self-calibration of the fluorescence signal and quantification of endogenous vicinal dithiols of VDPs. Its potential for in situ dynamic tracing of changes of protein vicinal dithiols under different cellular redox conditions was exemplified. VTAF facilitated the direct observation of subcellular distribution of endogenous VDPs via ratiometric fluorescence imaging and colocalization assay. And the results suggested that there are abundant VDPs in mitochondria. Moreover, some redox-sensitive VDPs are also present on cell surface which can respond to redox stimulus. This ratiometric fluorescence technique presents an important extension to previous fluorescence intensity-based probes for trapping and quantifying protein vicinal dithiols in living cells, as well as its visible dynamic tracing of VDPs.
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[A rapid method for the determination of hydrogen peroxide concentration].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 09-12-2014
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The present paper reported a spectrophotometry for the determination of hydrogen peroxide concentration. It is based on the reaction between ceric sulfate and hydrogen peroxide in an acidic medium, in which orange tetravalent cerium is converted to colorless trivalent cerium that causeds the change in absorbance. According to the quantitative relationship between ceric sulfate and hydrogen peroxide, the hydrogen peroxide concentration can be calculated. The selected conditions were as follows: detection wavelength of 480 nm, H2SO4 concentration of 0.5 mol x L(-1), and reaction time of 3.0 min. The results showed that the method has an excellent measurement precision (RSD = 0.31%) and accuracy (RSD < or = 0.91%) for the quantification of hydrogen peroxide. The present method is simple and rapid, with high detection sensitivity and low cost. It is suitable for use in rapid industrial analyses.
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A semiconductive superhard FeB? phase from first-principles calculations.
Phys Chem Chem Phys
PUBLISHED: 09-11-2014
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An oP10-FeB4 phase [H. Gou, et al., Phys. Rev. Lett., 2013, 111, 157002] was recently synthesized based on previous theoretical predictions. In this study, a high-pressure phase of FeB4 (tP10-FeB4) was proposed through first-principles calculations. The tP10-FeB4 structure, which contains two formula units per unit cell, belongs to tetragonal symmetry with the space group P42/nmc. The boron atoms in tP10-FeB4 are present as tetrahedron configurations. Enthalpies as a function of pressure indicate that this new phase is probable to achieve through a phase transition from the oP10-FeB4 phase above ?65.9 GPa. The softening of acoustic phonon at T points in the Brillouin zone may be the driving force behind the phase transition. Further analyses reveal that the tP10-FeB4 phase is a potential superhard semiconductor.
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The learning curve for minimally invasive Oxford phase 3 unicompartmental knee arthroplasty: cumulative summation test for learning curve (LC-CUSUM).
J Orthop Surg Res
PUBLISHED: 09-06-2014
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BackgroundThe minimally invasive Oxford unicompartmental knee arthroplasty (UKA) is a demanding procedure but has many advantages compared with total knee arthroplasty (TKA). The aim of this observational study was to investigate the learning curve of one experienced surgeon introducing minimally invasive Oxford phase 3 UKA into his routine clinical practice.MethodsThe first 50 consecutive cases of minimally invasive Oxford phase 3 UKA performed by one surgeon were evaluated to determine whether there was an association between outcomes and the cumulative number of cases performed, indicating the presence of learning curve. The cohort was divided into two groups: group A comprised the first 25 cases and group B cases 26¿50. Duration of surgery, blood loss, Hospital for Special Surgery score, range of motion, complications, and the radiographical position of the implant were compared between the groups. The cumulative summation test for learning curve (LC-CUSUM) was then used to further analyze the learning curve.ResultsThe mean age and follow-up were 64.4 years and 50.9 months, respectively. The duration of surgery and blood loss were significantly more favorable in group B. The length of incision gradually reduced from 9.7¿±¿1.3 to 8.5¿±¿1.1 cm. Failures were identified in nine patients (18%). Two revisions and two dislocations were encountered in group A; one revision was performed 4 years after surgery for a patient in group B because of a fracture. One case of lateral compartment osteoarthritis was identified in group A. Two patients in each group reported continuing unexplained pains. CUSUM analysis showed that failure rates diminished rapidly after 16 cases and reached an acceptable rate after 29 cases.ConclusionsMinimally invasive Oxford phase 3 UKA for anteromedial osteoarthritis is a demanding procedure, but satisfactory outcomes can be achieved after approximately 25 cases.
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Anti-oxidative stress effect of loading-dose rosuvastatin prior to percutaneous coronary intervention in patients with acute coronary syndrome: a prospective randomized controlled clinical trial.
Clin Drug Investig
PUBLISHED: 09-05-2014
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Administration of a loading dose of a statin (HMG-CoA reductase inhibitor) prior to percutaneous coronary intervention (PCI) contributes to protection from myocardial ischemic-reperfusion injury. This trial was designed to investigate the effect and mechanism of loading-dose rosuvastatin therapy before PCI in patients with acute coronary syndrome.
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Systematic transcriptome analysis of the zebrafish model of diamond-blackfan anemia induced by RPS24 deficiency.
BMC Genomics
PUBLISHED: 09-04-2014
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Diamond-Blackfan anemia (DBA) is a class of human diseases linked to defective ribosome biogenesis that results in clinical phenotypes. Genetic mutations in ribosome protein (RP) genes lead to DBA phenotypes, including hematopoietic defects and physical deformities. However, little is known about the global regulatory network as well as key miRNAs and gene pathways in the zebrafish model of DBA.
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Surface free energy activated high-throughput cell sorting.
Anal. Chem.
PUBLISHED: 09-03-2014
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Cell sorting is an important screening process in microbiology, biotechnology, and clinical research. Existing methods are mainly based on single-cell analysis as in flow cytometric and microfluidic cell sorters. Here we report a label-free bulk method for sorting cells by differentiating their characteristic surface free energies (SFEs). We demonstrated the feasibility of this method by sorting model binary cell mixtures of various bacterial species, including Pseudomonas putida KT2440, Enterococcus faecalis ATCC 29212, Salmonella Typhimurium ATCC 14028, and Escherichia coli DH5?. This method can effectively separate 10(10) bacterial cells within 30 min. Individual bacterial species can be sorted with up to 96% efficiency, and the cell viability ratio can be as high as 99%. In addition to its capacity of sorting evenly mixed bacterial cells, we demonstrated the feasibility of this method in selecting and enriching cells of minor populations in the mixture (presenting at only 1% in quantity) to a purity as high as 99%. This SFE-activated method may be used as a stand-alone method for quickly sorting a large quantity of bacterial cells or as a prescreening tool for microbial discrimination. Given its advantages of label-free, high-throughput, low cost, and simplicity, this SFE-activated cell sorting method has potential in various applications of sorting cells and abiotic particles.
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[Prevalence and features of pathogenic bacteria in the department of hematology without bone marrow transplantation in Peking Union Medical College Hospital from 2010 to 2012].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 09-02-2014
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To investigate the incidence,pathogens, and clinical features of infection in consecutive cases from 2010 to 2012 in Peking Union Medical College Hospital.
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Phenotypic and functional characterization of cytokine-induced killer cells derived from preterm and term infant cord blood.
Oncol. Rep.
PUBLISHED: 09-01-2014
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Cord blood has gradually become an important source for hematopoietic stem cell transplantation (HSCT) in the human, particularly in pediatric patients. Adoptive cellular immunotherapy of patients with hematologic malignancies after umbilical cord blood transplant is crucial. Cytokine?induced killer (CIK) cells derived from cord blood are a new type of antitumor immune effector cells in tumor prevention and treatment and have increasingly attracted the attention of researchers. On the other hand, it has been suggested that preterm infant cord blood retains an early differentiation phenotype suitable for immunotherapy. Therefore, we determined the phenotypic and functional characterization of CIK cells derived from preterm infant cord blood (PCB-CIK) compared with CIK cells from term infant cord blood (TCB-CIK). Twenty cord blood samples were collected and classified into two groups based on gestational age. Cord blood mononuclear cells (CBMCs) were isolated, cultured and induced to CIK cells in vitro. We used flow cytometry to detect cell surface markers, FlowJo software to analyze the proliferation profile and intracellular staining to test the secretion of cytokines. Finally, we evaluated the antitumor activity of CIK cells against K562 in vitro. Compared with TCB-CIK, PCB-CIK cells demonstrated faster proliferation and higher expression of activated cell surface markers. The secretion of IL-10 was lower in PCB-CIK cells while the expression of perforin and CD107a had no significant difference between the two cell groups. PCB-CIK cells exhibited a high proliferation rate while the cytotoxic activity had no difference between the PCB-CIK and TCB-CIK cells. Hence preterm infant cord blood may be a potential source for immunotherapy.
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Mercury removal from contaminated soil by thermal treatment with FeCl3 at reduced temperature.
Chemosphere
PUBLISHED: 08-30-2014
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Thermal treatment has been used to remediate mercury-contaminated soils; however, existing thermal technologies use high temperatures (e.g., 600-800°C) and require high energy costs. Moreover, the treated soil is unfavorable for agricultural reuse. To address these issues, the present study developed a method for the thermal treatment of mercury-contaminated soils at a reduced temperature (400°C) by adding FeCl3. A FeCl3/Hg molar ratio of 100:1 in the soil was adopted as the optimum dosage of FeCl3 required to achieve maximum reduction of mercury. The mercury concentration in soils was successfully reduced to 0.8mgkg(-)(1) when treated at 400°C for 60min and the treated soil retained most of its original soil properties. FeCl3 addition during thermal treatment not only accelerated the volatilization of mercury in the easily removed fraction but also reduced the volatilization temperature of mercury in the hardly removed fraction. The adsorbable organic halogens and PCDD/Fs formed during thermal treatment with FeCl3 would not affect the soil reuse in agriculture. The thermal decontamination method reduces energy costs and leads to agricultural soil reuse, thus providing a greener and more sustainable remediation method for treating mercury-contaminated soil in future engineering applications.
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A crystal structure-guided rational design switching non-carbohydrate inhibitors' specificity between two ?-GlcNAcase homologs.
Sci Rep
PUBLISHED: 08-26-2014
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Selective inhibition of function-specific ?-GlcNAcase has great potential in terms of drug design and biological research. The symmetrical bis-naphthalimide M-31850 was previously obtained by screening for specificity against human glycoconjugate-lytic ?-GlcNAcase. Using protein-ligand co-crystallization and molecular docking, we designed an unsymmetrical dyad of naphthalimide and thiadiazole, Q2, that changes naphthalimide specificity from against a human glycoconjugate-lytic ?-GlcNAcase to against insect and bacterial chitinolytic ?-GlcNAcases. The crystallographic and in silico studies reveal that the naphthalimide ring can be utilized to bind different parts of these enzyme homologs, providing a new starting point to design specific inhibitors. Moreover, Q2-induced closure of the substrate binding pocket is the structural basis for its 13-fold increment in inhibitory potency. Q2 is the first non-carbohydrate inhibitor against chitinolytic ?-GlcNAcases. This study provides a useful example of structure-based rationally designed inhibitors as potential pharmaceuticals or pesticides.
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Association between BRCA1 rs799917 polymorphism and breast cancer risk: A meta-analysis of 19,878 subjects.
Biomed. Pharmacother.
PUBLISHED: 08-14-2014
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Studies investigating the association between the BRCA1 rs799917 polymorphism and breast cancer risk have reported controversial results. In order to derive a more precise estimation of the relationship, we performed a comprehensive meta-analysis. A total of 8 articles comprising 19,878 subjects were included in this meta-analysis. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated by Stata 11 software. Heterogeneity tests were conducted by Q test with I(2) value, and publication bias assessment was performed by Begg's funnel plot and Egger's test. The pooled results did not show any sufficient evidence approving the association between the BRCA1 rs799917 polymorphism and breast cancer risk in total population (T vs C: OR=1.01, 95% CI=0.97-1.06; TT vs CC: OR=1.03, 95% CI=0.93-1.13; CT vs CC: OR=1.04, 95% CI=0.92-1.16; TT+CT vs CC: OR=1.04, 95% CI=0.94-1.15; TT vs CT+CC: OR=1.03, 95% CI=0.94-1.12). In the further subgroup analyses, no significant associations were found in any comparison models according to ethnicity and source of controls. No publication bias was observed in this meta-analysis. In summary, based on the overall results, this meta-analysis strongly suggests that the BRCA1 rs799917 polymorphism is not associated with breast cancer risk.
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Association between cytosolic serine hydroxymethyltransferase (SHMT1) gene polymorphism and cancer risk: a meta-analysis.
Biomed. Pharmacother.
PUBLISHED: 08-14-2014
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The serine hydroxymethyltransferase (SHMT1) is the key enzyme in the folate metabolic pathway to provide one-carbon unit that plays an important role in biosynthesis. Abnormal biosynthesis involved in DNA synthesis and methylation can lead to activation of oncogenes and inactivation of tumor suppressor genes. And the abnormal biosynthesis is closely related to a variety of common tumors' occurrence and development. A SNP in SHMT1 C1420T may effect the procession of biosynthesis and finally influence cancer occurrence.
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Functional characteristics of reversibly immortalized hepatic progenitor cells derived from mouse embryonic liver.
Cell. Physiol. Biochem.
PUBLISHED: 08-11-2014
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Liver is a vital organ and retains its regeneration capability throughout adulthood, which requires contributions from different cell populations, including liver precursors and intrahepatic stem cells. To overcome the mortality of hepatic progenitors (iHPs) in vitro, we aim to establish reversibly immortalized hepatic progenitor cells from mouse embryonic liver.
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Enhanced degradation of biphenyl from PCB-contaminated sediments: the impact of extracellular organic matter from Micrococcus luteus.
Appl. Microbiol. Biotechnol.
PUBLISHED: 08-08-2014
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Recent advances in the bioremediation of polychlorinated biphenyl (PCB)-contaminated environments have focused on the development of approaches to stimulate the activities of indigenous bacterial communities. In this study, extracellular organic matter (EOM) from Micrococcus luteus was used to enhance the biphenyl-degrading capability of potentially functional microorganisms. The obtained results suggest that EOM significantly enhanced the biphenyl (BP)-degradation capability. Under a concentration of 3,500 mg/L BP, BP-degradation efficiency reached 60.8 % at a dosage of 10 % EOM (v/v), whereas the degradation efficiencies of control group (with inactivated EOM addition) and blank group (with lactate minimal medium) were only 21.5 and 6.2 %, respectively. Denaturing gradient gel electrophoresis (DGGE) profiles demonstrated that EOM played a key role in shifts in the composition and diversity of bacterial community. The Illumina high-throughput sequencing analysis indicated that the genera of Rhodococcus and Pseudomonas closely related to BP/PCB-degradation were greatly abundant after EOM addition. Together with polymerase chain reaction (PCR)-DGGE analysis, the link between the enhanced BP-degrading capability and the stimulation and resuscitation function of EOM in uncultured bacteria belonging to phylum Actinobacteria was tentatively established. These results suggest that EOM from M. luteus as an additive holds great potential for the efficient and cost-effective bioremediation of PCB-contaminated environment.
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The epidemiology of Plasmodium vivax and Plasmodium falciparum malaria in China, 2004-2012: from intensified control to elimination.
Malar. J.
PUBLISHED: 08-07-2014
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In China, the national malaria elimination programme has been operating since 2010. This study aimed to explore the epidemiological changes in patterns of malaria in China from intensified control to elimination stages.
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A computational study on the photoelectric properties of various Bi2O 3 polymorphs as visible-light driven photocatalysts.
J Mol Model
PUBLISHED: 08-03-2014
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This paper presents first-principle studies on the photoelectric properties of various Bi2O3 polymorphs. The intrinsic reason of different photocatalytic activities was revealed by electronic structures and optical features. Results showed that for ?, ?, and ?-Bi2O3, the top of valence bands were mainly constructed by Bi6s and O2p orbitals, and the bottom of conduction bands were dominantly composed by Bi6p orbital. However, two intermediate bands were found at the Fermi level for ?-Bi2O3, which leads to a two-step transition from the top of valence band to the bottom of conduction band and facilitates electron transition under irradiation. Absent forbidden gap was found in ?-Bi2O3, resulting in a semimetallic character due to its intrinsic oxygen vacancy and high ionic conductivity. Moreover, the optical properties of ?, ?, and ?-Bi2O3 were investigated by absorption spectrum, dielectric constant function, and energy loss spectroscopy. We concluded that the photocatalytic activities followed in the order of ?-Bi2O3?>??-Bi2O3?>??-Bi2O3, in accord with the experimental report. Calculation results illustrated the experimental observations and provided a useful guidance in exploring promising visible-light semiconductor photocatalysts.
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Synthesis and evaluation of benzimidazole carbamates bearing indole moieties for antiproliferative and antitubulin activities.
Eur J Med Chem
PUBLISHED: 07-18-2014
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A series of novel benzimidazole carbamates bearing indole moieties with sulphur or selenium atoms connecting the aromatic rings were synthesised and evaluated for their antiproliferative activities against three human cancer cell lines (SGC-7901, A-549 and HT-1080) using an MTT assay. Compounds 10a, 10b, 7a, 7b and 7f showed significant activities against these cell lines. The most potent compound in this series, 10a, was selected to investigate its antitumour mechanism. In addition, molecular docking studies suggested that compound 10a interacts very closely with the nocodazole docking pose through hydrogen bonds at the colchicine binding site of tubulin.
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Dihydrochalcones and homoisoflavanes from the red resin of Dracaena cochinchinensis (Chinese dragon's blood).
Fitoterapia
PUBLISHED: 07-12-2014
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Two new dihydrochalcones, 4-hydroxy-2,4'-dimethoxydihydrochalcone (1) and 3,4'-dihydroxy-2,4,6-trimethoxydihydrochalcone (2), and a new homoisoflavane, 7,3'-dihydroxy-8,4'-dimethoxyhomoisoflavane (3), along with 12 known compounds (4-15), were isolated from the red resin of Dracaena cochinchinensis (Chinese dragon's blood). Their structures were assigned by a variety of spectroscopic techniques. Diversity of cleavage pathways were proposed for dihydrochalcones and homoisoflavanes based on the mass spectroscopic behaviors of those identified compounds using hybrid ion trap-time of flight mass spectrometry. All the compounds were evaluated for their inhibitory effects on nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophages, and compound 9 exhibited mild inhibition of NO production in this assay with IC50 value of 50.3?M.
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Fluorescence-based ion-sensing with colloidal particles.
Curr Opin Pharmacol
PUBLISHED: 07-09-2014
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Particle-based fluorescence sensors for the quantification of specific ions can be made by coupling ion-sensitive fluorophores to carrier particles, or by using intrinsically fluorescent particles whose fluorescence properties depend on the concentration of the ions. Despite the advantages of such particle-based sensors for the quantitative detection of ions, such as the possibility to tune the surface chemistry and thus entry portal of the sensor particles to cells, they have also some associated problems. Problems involve for example crosstalk of the ion-sensitive fluorescence read-out with pH, or spectral overlap of the emission spectra of different fluorescent particles in multiplexing formats. Here the benefits of using particle-based fluorescence sensors, their limitations and strategies to overcome these limitations will be described and exemplified with selected examples.
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The Evidence for the Contribution of the Autism Susceptibility Candidate 2 (AUTS2) Gene in Heroin Dependence Susceptibility.
J. Mol. Neurosci.
PUBLISHED: 07-08-2014
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The single-nucleotide polymorphisms (SNP) rs6943555 in autism susceptibility candidate 2 (AUTS2) has been reported to be significantly associated with alcohol consumption in Europeans. In this study, we identified the SNP in AUTS2 contributing to the genetic susceptibility to heroin dependence. The potential association between heroin dependence and 21 SNPs (rs2270162, rs2851510, rs513150, rs595681, rs210606, rs10237984, rs13228123, rs10235781, rs6969375, rs6943555, rs10251416, rs17141963, rs12669427, rs723340, rs2293507, rs2293508, rs6960426, rs9886351, rs2293501, rs10277450, rs1918425) of AUTS2 was examined in a Chinese Han population using the MassARRAY system. The participants included 426 patients with heroin dependence and 416 healthy controls. Single SNP association, haplotype association, and clinical phenotype association were analyzed. Single SNP association revealed that AA homozygotes of rs6943555 were significantly over-represented in the patients with heroin dependence compared with the control subjects (P?=?0.0019). The patients with heroin dependence had a significantly higher frequency of the A allele (P?=?0.0003, odd ratio (OR)?=?1.429, 95 % confidence interval (CI)?=?1.175-1.738). Strong linkage disequilibrium (LD) was observed in five blocks (D'?>?0.9). In block 2, significantly more A-A haplotypes (P?=?0.006 after Bonferroni corrections) and significantly fewer T-A haplotypes (P?=?0.040) were found in the patients with heroin dependence. The genotype and clinical phenotype correlation study of the rs6943555 carriers showed that the amount of heroin self-injection was lower in the patients with the AA genotype relative to AT + TT genotypes (P?
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Correlation of high-molecular-weight adiponectin and leptin concentrations with anthropometric parameters and insulin sensitivity in newborns.
Int J Endocrinol
PUBLISHED: 07-08-2014
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Objective. High-molecular-weight adiponectin (HMW-adiponectin) and leptin are two important adipokines. The aim of this study was to examine the association between the two adipokines and anthropometric measurements of neonates at birth. Furthermore, we would like to explore whether HMW-adiponectin and leptin correlate with insulin sensitivity in neonates. Methods. Venous cord blood samples were obtained from 266 full-term healthy neonates consecutively born at Peking Union Medical College Hospital. HMW-adiponectin, leptin, blood glucose, and insulin concentrations were measured. Results. HMW-adiponectin and leptin were significantly higher in females compared with males (P = 0.031 and P = 0.000, resp.). Univariate correlation analysis showed that leptin concentrations in cord blood were positively associated with gestational age, birth weight, body length, ponderal index, placenta weight, insulin, and insulin sensitivity (all P < 0.001). However, there was no correlation between cord blood HMW-adiponectin levels and foetal anthropometric measurements or foetal insulin sensitivity indicators (all P > 0.05). Multivariate linear regression analysis indicated that leptin (B = -0.126, P = 0.045) in cord blood was independently associated with insulin sensitivity. Conclusions. Leptin concentrations, but not HMW-adiponectin, were positively associated with foetal anthropometric measurements. Leptin concentrations are significantly associated with foetal insulin sensitivity, and there were no significant correlations between HMW-adiponectin levels and foetal insulin sensitivity.
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An unnatural amino acid based fluorescent probe for phenylalanine ammonia lyase.
Org. Biomol. Chem.
PUBLISHED: 06-28-2014
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A fluorescent probe (2a-LP) based on an unnatural amino acid (UAA) is developed for the detection of phenylalanine ammonia lyase (PAL). In the presence of PAL, 2a-LP is catalytically deaminated to ortho-amino-transcinnamic acid (o-a-CA), which shows a remarkable “off–on” fluorescence signal. Thus, the probe 2a-LP enables direct visualization of the PAL activity in tomato under UV illumination and has potential in vitro assays.
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Characteristics of surface O3 over Qinghai Lake area in Northeast Tibetan Plateau, China.
Sci. Total Environ.
PUBLISHED: 06-20-2014
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Surface O3 was monitored continuously during Aug. 12, 2010 to Jul. 21, 2011 at a high elevation site (3200m above sea level) in Qinghai Lake area (36°58'37?N, 99°53'56?E) in Northeast Tibetan Plateau, China. Daily average O3 ranged from 21.8ppbv to 65.3ppbv with an annual average of 41.0ppbv. Seasonal average of O3 followed a decreasing order of summer>autumn>spring>winter. Diurnal variations of O3 showed low concentrations during daytime and high concentrations during late night and early morning. An intensive campaign was also conducted during Aug. 13-31, 2010 to investigate correlations between meteorological or chemical conditions and O3. It was found that O3 was poorly correlated with solar radiation due to the insufficient NOx in the ambient air, thus limiting O3 formation under strong solar radiation. In contrast, high O3 levels always coincided with strong winds, suggesting that stratospheric O3 and long range transport might be the main sources of O3 in this rural area. Back-trajectory analysis supported this hypothesis and further indicated the transport of air masses from northwest, northeast and southeast directions.
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Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage.
Neuroradiology
PUBLISHED: 06-09-2014
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The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH).
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Associations between thyroid autoantibody status and abnormal pregnancy outcomes in euthyroid women.
Endocrine
PUBLISHED: 05-30-2014
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We investigated whether thyroid autoantibody status influences pregnancy outcomes in euthyroid women, by comparing abnormal pregnancy outcome rates between those who tested positive for thyroid autoantibodies (Ab(+)) and those who tested autoantibody-negative (Ab(-)). Euthyroid pregnant women (n = 7,641) underwent tests for serum thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb). The subjects were divided into 4 groups according to thyroid antibody status: TPOAb(-)/TgAb(-) (92.9 %); TPOAb(+)/TgAb(-) (3.2 %); TPOAb(-)/TgAb(+) (2.0 %); and TPOAb(+)/TgAb(+) (1.9 %). The incidence rates of the following abnormal pregnancy outcomes were compared among the 4 groups and analyzed by Fisher's exact test: gestational diabetes, gestational hypertension, placenta previa, placental abruption, premature rupture of fetal membrane (PROM), intrauterine growth restriction, fetal distress, fetal anomalies, stillbirth, preterm birth, and low birth weight. Among the 4 groups, there were no significant differences in age, gestational age, or in the incidence rates of abnormal pregnancy outcomes, except for PROM and low birth weight. The highest incidence rates for PROM and low birth weight were in the TPOAb(-)/TgAb(+) and TPOAb(+)/TgAb(+) subjects, respectively. TgAb positivity and TPOAb positivity were associated with PROM and low birth weight, respectively. Underlying factors that govern the association between thyroid autoantibodies and PROM and low birth weight require further investigation.
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High-throughput generation of an activation-tagged mutant library for functional genomic analyses in tobacco.
Planta
PUBLISHED: 05-27-2014
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Tobacco (Nicotiana tabacum L.) is an ideal model system for molecular biological and genetic studies. In this study, activation tagging was used to generate approximately 100,000 transgenic tobacco plants. Southern blot analysis indicated that there were 1.6 T-DNA inserts per line on average in our transformed population. The phenotypes observed include abnormalities in leaf and flower morphology, plant height, flowering time, branching, and fertility. Among 6,000 plants in the T0 generation, 57 displayed obvious phenotypes. Among 4,105 lines in the T1 generation, 311 displayed abnormal phenotypes. Fusion primer and nested integrated PCR was used to identify 963 independent genomic loci of T-DNA insertion sites in 1,257 T1 lines. The distribution of T-DNA insertions was non-uniform and correlated well with the predicted gene density along each chromosome. The insertions were biased toward genic regions and noncoding regions within 5 kb of a gene. Fifteen plants that showed the same phenotype as their parent with a dominant pattern in the T2 generation were chosen randomly to detect the expression levels of genes adjacent to the T-DNA integration sites by semi-quantitative RT-PCR. Fifteen candidate genes were identified. Activation was observed in 7 out of the 15 adjacent genes, including one that was located 13.1 kb away from the enhancer sequence. The activation-tagged population described in this paper will be a highly valuable resource for tobacco functional genomics research using both forward and reverse genetic approaches.
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Mechanism of dialkyl phthalates removal from aqueous solution using ?-cyclodextrin and starch based polyurethane polymer adsorbents.
Carbohydr Polym
PUBLISHED: 05-04-2014
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Phthalate esters have been known as potent endocrine disruptors and carcinogens; and their removal from water have been of considerable concern recently. In the present study, ?-cyclodextrin polyurethane polymer (GPP), ?-cyclodextrin/starch polyurethane copolymer (GSP), and starch polyurethane polymer (SPP) have been synthesized and characterized. Their adsorption efficiencies for the removal of dimethyl phthalate (DMP) and diethyl phthalate (DEP) from aqueous solutions were investigated. The characterization results showed the success of the synthesis. The isotherms were L-type, and both the Langmuir and Freundlich adsorption isotherm gave good fittings to the adsorption data. Adsorption mechanisms suggested that these adsorbents spontaneously adsorb phthalate molecules driven mainly by enthalpy change, and the adsorption process was attributed to multiple adsorbent-adsorbate interactions such as hydrogen bonding, ?-? stacking, and pore filling. The results showed that starch and ?-cyclodextrin polyurethane polymer adsorbents have excellent potential as adsorbent materials for the removal of phthalates from the contaminated water.
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Effects of Chinese Medicine Shen-Fu Injection () on the expression of inflammatory cytokines and complements during post-resuscitation immune dysfunction in a porcine model.
Chin J Integr Med
PUBLISHED: 04-30-2014
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To investigate the action of Shen-Fu Injection (, SFI) in regulating the expression of the serum complements and inflammatory cytokines synthesized and released in response to the stress of global ischemia accompanying cardiac arrest (CA) and resuscitation.
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MicroRNA-93 suppress colorectal cancer development via Wnt/?-catenin pathway downregulating.
Tumour Biol.
PUBLISHED: 04-29-2014
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MicroRNA-93 (miR-93) is involved in several carcinoma progressions. It has been reported that miR-93 acts as a promoter or suppressor in different tumors. However, till now, the role of miR-93 in colon cancer is unclear. Herein, we have found that expression of miR-93 was lower in human colon cancer tissue and colorectal carcinoma cell lines compared with normal colon mucosa. Forced expression of miR-93 in colon cancer cells inhibits colon cancer invasion, migration, and proliferation. Furthermore, miR-93 may downregulate the Wnt/?-catenin pathway, which was confirmed by measuring the expression level of the ?-catenin, axin, c-Myc, and cyclin-D1 in this pathway. Mothers against decapentaplegic homolog 7 (Smad7), as an essential molecular protein for nuclear accumulation of ?-catenin in the canonical Wnt signaling pathway, is predicted as a putative target gene of miR-93 by the silico method and demonstrated that it may be suppressed by targeting its 3'UTR. These findings showed that miR-93 suppresses colorectal cancer development via downregulating Wnt/?-catenin, at least in part, by targeting Smad7. This study revealed that miR-93 is an important negative regulator in colon cancer and suggested that miR-93 may serve as a novel therapeutic agent that offers benefits for colon cancer treatment.
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Rapid screening and identification of target constituents using full scan-parent ions list-dynamic exclusion acquisition coupled to diagnostic product ions analysis on a hybrid LTQ-Orbitrap mass spectrometer.
Talanta
PUBLISHED: 04-29-2014
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A highly sensitive and effective strategy for rapid screening and identification of target constituents has been developed using full scan-parent ions list-dynamic exclusion (FS-PIL-DE) acquisition coupled to diagnostic product ions (DPIs) analysis on a hybrid LTQ-Orbitrap mass spectrometer. The FS-PIL-DE was adopted as a survey scan to trigger the MS/MS acquisition of all the predictable constituents contained in traditional Chinese medicines. Additionally, DPIs analysis can provide a criterion to judge the target constituents detected into certain chemical families. Results from analyzing polymethoxylated flavonoids (PMFs) in the leaves of Citrus reticulata Blanco demonstrated that FS-PIL-DE was capable of targeting a greater number of constituents than FS, FS-PIL and FS-DE, thereby increasing the coverage of constituent screening. As a result, 135 PMFs including 81 polymethoxyflavones, 54 polymethoxyflavanones or polymethoxychalcones were identified preliminarily. And this was the first time to systematically report the presence of PMFs in the leaves of Citrus reticulata Blanco, especially for polymethoxylated flavanones and chalcones, most of which were new compounds. The results indicated that the developed FS-PIL-DE coupled to DPIs analysis methodology could be employed as a rapid, effective technique to screen and identify target constituents from TCMs extracts and other organic matter mixtures whose compounds contained can also be classified into families based on the common carbon skeletons.
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Diagnostic and prognostic value of neutrophil gelatinase-associated lipocalin, matrix metalloproteinase-9, and tissue inhibitor of matrix metalloproteinases-1 for sepsis in the ED: an observational study.
Crit Care
PUBLISHED: 04-26-2014
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IntroductionThe aim of this study was to evaluate the early diagnostic, risk stratification and prognostic value of neutrophil gelatinase-associated lipocalin (NGAL), matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), compared with procalcitonin (PCT) and the Mortality in Emergency Department Sepsis (MEDS) score in septic patients in the emergency department (ED).MethodsIn total, 480 consecutive adult patients were enrolled in this study. They fulfilled the systemic inflammatory response syndrome (SIRS) criteria and were admitted to the ED of Beijing Chaoyang Hospital from February 2013 to August 2013. A total of 40 healthy controls comprised the control group. The patients were classified into four groups: SIRS, sepsis, severe sepsis, and septic shock. Serum NGAL, MMP-9, TIMP-1 and PCT were measured, and MEDS score was calculated at enrollment. The prognostic values of NGAL, MMP-9 and TIMP-1 were compared with PCT and MEDS score. A 28-day follow-up was performed for all patients.ResultsThe median levels of serum NGAL and TIMP-1 increased with sepsis severity. The areas under the receiver operating characteristic (AUC) curves of NGAL or TIMP-1 were greater than those of PCT and MEDS score in diagnosing and predicting 28-day mortality, and the AUC of a combination of NGAL and MEDS score or TIMP-1 and MEDS score was more significant. Serum NGAL, MMP-9 and TIMP-1 levels were significantly higher in non-survivors than survivors at 28 days¿ follow-up. In addition, the level of NGAL was much higher in septic patients with acute kidney injury (AKI) than those without AKI. NGAL, TIMP-1, MMP-9 and MEDS score were found to be independent predictors of 28-day mortality in septic patients. The levels of serum NGAL and TIMP-1 were positively correlated with PCT and MEDS score in every septic group.ConclusionsNGAL and TIMP-1 are valuable for the risk stratification, early diagnosis and prognostication of sepsis in the ED. NGAL is also a valuable biomarker for prognosis of septic patients with AKI in the ED.
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Unique tri-output optical probe for specific and ultrasensitive detection of hydrazine.
Anal. Chem.
PUBLISHED: 04-17-2014
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An optical probe based on colorimetric and ratiometric as well as chemiluminometric signal outputs is developed for the specific detection of hydrazine. On the basis of a Gabriel-type reaction, hydrazinolysis of a simple probe CF (4-phtalamide-N-(4'-methylcoumarin) naphthalimide) produces both the fluorescence of 7-amino-4-methylcoumarin with the max emission wavelength changed from 480 to 420 nm (along with a color change from yellow to transparent) and the luminol chemiluminescence activated by H2O2 with a max emission wavelength at 450 nm. The experimental detection limit of hydrazine is 3.2 ppb (0.1 ?M). Selectivity experiments proved CF has excellent selectivity to hydrazine over other interfering substances. Probe CF was also successfully applied in the vapor hydrazine detection over other interfering volatile analytes. Furthermore, the probe CF loaded thin-layer chromatography (TLC) plate for vapor hydrazine detection limit is 5.4 mg/m(3) which is well below the half lethal dose of hydrazine gas for mice (LC50(mice), 330 mg/m(3)) and National Institute of Occupational Safety and Health's immediately dangerous to life or health limit (NIOSHIDLH, 66 mg/m(3)). With H2O2, only hydrazinolysis product luminol can be lighted at 450 nm, other species have no signal. Probe CF can also be used for the detection of hydrazine in HeLa cells.
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Identification and characterization of telocytes in the uterus of the oviduct in the Chinese soft-shelled turtle, Pelodiscus sinensis: TEM evidence.
J. Cell. Mol. Med.
PUBLISHED: 04-12-2014
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Telocytes (Tcs) are cells with telopodes (Tps), which are very long cellular extensions with alternating thin segments (podomers) and dilated bead-like thick regions known as podoms. Tcs are a distinct category of interstitial cells and have been identified in many mammalian organs including heart, lung and kidney. The present study investigates the existence, ultrastructure, distribution and contacts of Tcs with surrounding cells in the uterus (shell gland) of the oviduct of the Chinese soft-shelled turtle, Pelodiscus sinensis. Samples from the uterine segment of the oviduct were examined by transmission electron microscopy. Tcs were mainly located in the lamina propria beneath the simple columnar epithelium of the uterus and were situated close to nerve endings, capillaries, collagen fibres and secretory glands. The complete morphology of Tcs and Tps was clearly observed and our data confirmed the existence of Tcs in the uterus of the Chinese soft-shelled turtle Pelodiscus sinensis. Our results suggest these cells contribute to the function of the secretory glands and contraction of the uterus.
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Thieno[3,2-b]thiophene-Diketopyrrolopyrrole-Based Quinoidal Small Molecules: Synthesis, Characterization, Redox Behavior, and n-Channel Organic Field-Effect Transistors.
Chemistry
PUBLISHED: 04-11-2014
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We report the synthesis, characterization, redox behavior, and n-channel organic field-effect (OFET) characteristics of a new class of thieno[3,2-b]thiophene-diketopyrrolopyrrole-based quinoidal small molecules 3 and 4. Under ambient atmosphere, solution-processed thin-film transistors based on 3 and 4 exhibit maximum electron mobilities up to 0.22 and 0.16?cm(2) ?V(-1) ?s(-1) , respectively, with on-off current ratios (Ion /Ioff ) of more than than 10(6) . Cyclic voltammetry analysis showed that this class of quinoidal derivatives exhibited excellent reversible two-stage reduction behavior. This property was further investigated by a stepwise reductive titration of 4, in which sequential reduction to the radical anion and then the dianion were observed.
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Novel metal complexes of naphthalimide-cyclam conjugates as potential multi-target receptor tyrosine kinase (RTK) inhibitors: synthesis and biological evaluation.
Eur J Med Chem
PUBLISHED: 03-19-2014
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A novel series of metal complexes of naphthalimide-cyclam conjugates were synthesized and their in vitro antitumor activities were evaluated. The newly-synthesized compounds showed huge diversity of antiproliferative potency due to variety of metal ions and length of alkyl chains, among which the Zn(II) and Cr(III) complexes exhibited comparable antiproliferative activities with amonafide via multiple tyrosine kinase inhibition. Further research revealed that the representative compound 8a displayed broad-spectrum antiproliferative activity against 15 cancer cell lines with average IC50 value 10.18 ± 3.25 ?M, and effective antiangiogenic activity on human microvascular endothelial cells (HMEC-1). In brief, metal complexes of naphthalimide-cyclam conjugates were firstly designed and synthesized as multi-target tyrosine kinase inhibitors and proved of their antitumor capacities.
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Prognostic significance of hypothalamic-pituitary-adrenal axis hormones in early sepsis: a study performed in the emergency department.
Intensive Care Med
PUBLISHED: 03-03-2014
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The response of the hypothalamic-pituitary-adrenal (HPA) axis to the sustained stress of sepsis has been the focus of study in recent years because the early phase of sepsis is known to be dominated by major alterations in the HPA axis. This prospective observational study aimed at assessing the predictive values of copeptin and HPA hormones in determining sepsis progression and mortality in the emergency department (ED).
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Multifunctional hydrogels based on ?-cyclodextrin with both biomineralization and anti-inflammatory properties.
Carbohydr Polym
PUBLISHED: 02-11-2014
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In this study, a series of carboxylated hydrogels are synthesized using ?-cyclodextrin, epichlorohydrin and succinic anhydride. It is found that the carboxyl groups on the ?-cyclodextrin hydrogels could facilitate the biomineralization process in the simulated body fluid. The new generated minerals are apatite and similar to that of bones. Meanwhile, the carboxylated ?-cyclodextrin hydrogels can also load and release anti-inflammatory drug (using indomethacin as a model) in a controlled manner during the biomineralization process for 28 days. The carboxylated ?-cyclodextrin hydrogels also have low cytotoxicity and are promising for bone tissue engineering.
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Preparation and in vitro immunomodulatory effect of curdlan sulfate.
Carbohydr Polym
PUBLISHED: 02-11-2014
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Different curdlan sulfates were synthesized by modification of curdlan with sulfur trioxide-pyridine complex, and the one with the highest sulfur content (9.23 ± 0.16) %, CS3, was used to study the immunomodulating effect on murine RAW264.7 macrophages and bone marrow derived dendritic cells (BMDCs). The results showed that the treatment of macrophages with CS3 could not only increase the nitric oxide (NO) release and the cytokines TNF-?, IL-6 and IL-1? production significantly, but also enhance the inducible NOS (iNOS) expression, NF-?Bp65 nuclear translocation, Erk1/2 and SAPK/JNK phosphorylation. The combination of CS3 with GM-CSF upregulated immature BMDCs to express major histocompatibility complex II (MHCII) and CD11c surface markers, CD40, CD80 and CD86 costimulatory molecules, as well as the cytokines of IL-12p70 and IL-6. The surface plasmon resonance (SPR) analysis found that CS3 exhibited binding affinity against dectin-1. These results suggested that curdlan sulfate can possibly be developed as a new immunotherapy agent and anti-viral vaccine adjuvant.
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Rhodamine-based fluorescent off-on sensor for Fe3+--in aqueous solution and in living cells: 8-aminoquinoline receptor and 2:1 binding.
Dalton Trans
PUBLISHED: 01-21-2014
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8-Aminoquinoline (8-AQ) and 2-aminopyridine (AmPyr) both as ionophoric agents were robustly used in development of a cation sensor. To evaluate the effect of complexation with cations, flexible 2-aminopyridine and rigid 8-AQ moiety were directly introduced into rhodamine chromophore and two candidate fluorescent sensors were constructed successfully. Rh-AQ with a rigid 8-AQ fragment exhibited turn-on fluorescence and color responses to Fe(3+) ion over other metal ions related to biology in aqueous solution. The sensor Rh-AmPyr with a flexible 2-aminopyridine did not give positive responses to cations although with a similar binding cavity as on Rh-AQ. Furthermore, the 2:1 recognition mode of Rh-AQ with Fe(3+) was proved according to the 1D and 2D COSY H–H NMR experiments. The live cell imaging experiments demonstrated that Rh-AQ could be successfully applied as a bioimaging agent for monitoring Fe(3+) in living cells.
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Quantitatively mapping cellular viscosity with detailed organelle information via a designed PET fluorescent probe.
Sci Rep
PUBLISHED: 01-03-2014
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Viscosity is a fundamental physical parameter that influences diffusion in biological processes. The distribution of intracellular viscosity is highly heterogeneous, and it is challenging to obtain a full map of cellular viscosity with detailed organelle information. In this work, we report 1 as the first fluorescent viscosity probe which is able to quantitatively map cellular viscosity with detailed organelle information based on the PET mechanism. This probe exhibited a significant ratiometric fluorescence intensity enhancement as solvent viscosity increases. The emission intensity increase was attributed to combined effects of the inhibition of PET due to restricted conformational access (favorable for FRET, but not for PET), and the decreased PET efficiency caused by viscosity-dependent twisted intramolecular charge transfer (TICT). A full map of subcellular viscosity was successfully constructed via fluorescent ratiometric detection and fluorescence lifetime imaging; it was found that lysosomal regions in a cell possess the highest viscosity, followed by mitochondrial regions.
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Identifying MicroRNAs Involved in Aging of the Lateral Wall of the Cochlear Duct.
PLoS ONE
PUBLISHED: 01-01-2014
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Age-related hearing loss is a progressive sensorineural hearing loss that occurs during aging. Degeneration of the organ of Corti and atrophy of the lateral wall of the cochlear duct (or scala media) in the inner ear are the two primary causes. MicroRNAs (miRNAs), a class of short non-coding RNAs that regulate the expression of mRNA/protein targets, are important regulators of cellular senescence and aging. We examined miRNA gene expression profiles in the lateral wall of two mouse strains, along with exploration of the potential targets of those miRNAs that showed dynamic expression during aging. We show that 95 and 60 miRNAs exhibited differential expression in C57 and CBA mice during aging, respectively. A majority of downregulated miRNAs are known to regulate pathways of cell proliferation and differentiation, while all upregulated miRNAs are known regulators in the pro-apoptotic pathways. By using apoptosis-related gene array and bioinformatic approaches to predict miRNA targets, we identify candidate miRNA-regulated genes that regulate apoptosis pathways in the lateral wall of C57 and CBA mice during aging.
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A Simplified and Versatile System for the Simultaneous Expression of Multiple siRNAs in Mammalian Cells Using Gibson DNA Assembly.
PLoS ONE
PUBLISHED: 01-01-2014
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RNA interference (RNAi) denotes sequence-specific mRNA degradation induced by short interfering double-stranded RNA (siRNA) and has become a revolutionary tool for functional annotation of mammalian genes, as well as for development of novel therapeutics. The practical applications of RNAi are usually achieved by expressing short hairpin RNAs (shRNAs) or siRNAs in cells. However, a major technical challenge is to simultaneously express multiple siRNAs to silence one or more genes. We previously developed pSOS system, in which siRNA duplexes are made from oligo templates driven by opposing U6 and H1 promoters. While effective, it is not equipped to express multiple siRNAs in a single vector. Gibson DNA Assembly (GDA) is an in vitro recombination system that has the capacity to assemble multiple overlapping DNA molecules in a single isothermal step. Here, we developed a GDA-based pSOK assembly system for constructing single vectors that express multiple siRNA sites. The assembly fragments were generated by PCR amplifications from the U6-H1 template vector pB2B. GDA assembly specificity was conferred by the overlapping unique siRNA sequences of insert fragments. To prove the technical feasibility, we constructed pSOK vectors that contain four siRNA sites and three siRNA sites targeting human and mouse ?-catenin, respectively. The assembly reactions were efficient, and candidate clones were readily identified by PCR screening. Multiple ?-catenin siRNAs effectively silenced endogenous ?-catenin expression, inhibited Wnt3A-induced ?-catenin/Tcf4 reporter activity and expression of Wnt/?-catenin downstream genes. Silencing ?-catenin in mesenchymal stem cells inhibited Wnt3A-induced early osteogenic differentiation and significantly diminished synergistic osteogenic activity between BMP9 and Wnt3A in vitro and in vivo. These findings demonstrate that the GDA-based pSOK system has been proven simplistic, effective and versatile for simultaneous expression of multiple siRNAs. Thus, the reported pSOK system should be a valuable tool for gene function studies and development of novel therapeutics.
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Effects of Subclinical Hypothyroidism on Maternal and Perinatal Outcomes during Pregnancy: A Single-Center Cohort Study of a Chinese Population.
PLoS ONE
PUBLISHED: 01-01-2014
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Adverse maternal outcomes and perinatal complications are closely associated with overt maternal hypothyroidism, but whether these complications occur in women with subclinical hypothyroidism (SCH) during pregnancy remains controversial. The aim of this study was to evaluate the effects of SCH on maternal and perinatal outcomes during pregnancy.
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In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?
Beilstein J Nanotechnol
PUBLISHED: 01-01-2014
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The interfacing of colloidal nanoparticles with mammalian cells is now well into its second decade. In this review our goal is to highlight the more generally accepted concepts that we have gleaned from nearly twenty years of research. While details of these complex interactions strongly depend, amongst others, upon the specific properties of the nanoparticles used, the cell type, and their environmental conditions, a number of fundamental principles exist, which are outlined in this review.
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A highly sensitive long-wavelength fluorescence probe for nitroreductase and hypoxia: selective detection and quantification.
Chem. Commun. (Camb.)
PUBLISHED: 10-15-2013
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A novel long-wavelength fluorescence probe has been developed for the detection of nitroreductase (NTR) and hypoxia. could be activated by NTR at 0.1 ?M to release the fluorophore and significant changes in fluorescence emission at 658 nm were observed. This feature makes it advantageous for imaging hypoxic cells with minimal endogenous interference.
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In situ visualization and detection of protein sulfenylation responses in living cells through a dimedone-based fluorescent probe.
Org. Biomol. Chem.
PUBLISHED: 10-08-2013
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Sulfenylation is one of the reversible post-translational modifications, playing significant roles in cellular redox homeostasis and signaling systems. Herein, small fluorescent probe (CPD and CPDDM) based live-cell labelling technology for the visualization of protein sulfenylation responses in living cells has been developed. This approach enables the detection of protein sulfenylation without the need for cell lysis, fixation or purification, and permits the noninvasive study of protein sulfenylation in live cells through the direct fluorescent readout. This technology also can realize dynamic tracking of protein sulfenylation in situ with minimal perturbation to sulfenylated proteins and less interference with cellular function. Information on the global distribution and dynamic changes of endogenous protein sulfenylation has been obtained.
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Exploring unsymmetrical dyads as efficient inhibitors against the insect ?-N-acetyl-d-hexosaminidase OfHex2.
Biochimie
PUBLISHED: 07-23-2013
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The GH20 ?-N-acetyl-d-hexosaminidase OfHex2 from the insect Ostrinia furnacalis (Guenée) is a target potential for eco-friendly pesticide development. Although carbohydrate-based inhibitors against ?-N-acetyl-d-hexosaminidases are widely studied, highly efficient, non-carbohydrate inhibitors are more attractive due to low cost and readily synthetic manner. Based on molecular modeling analysis of the catalytic domain of OfHex2, a series of novel naphthalimide-scaffold conjugated with a small aromatic moiety by an alkylamine spacer linker were designed and evaluated as efficiently competitive inhibitors against OfHex2. The most potent one containing naphthalimide and phenyl groups spanning by an N-alkylamine linker has a Ki value of 0.37 ?M, which is 6 fold lower than that of M-31850, the most potent non-carbohydrate inhibitor ever reported. The straightforward synthetic manners as well as the presumed binding model in this paper could be advantageous for further structural optimization for developing inhibitors against GH20 ?-N-acetyl-d-hexosaminidases.
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"Integrated" and "insulated" boronate-based fluorescent probes for the detection of hydrogen peroxide.
Chem. Commun. (Camb.)
PUBLISHED: 06-15-2013
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Integrated and insulated boronate-based fluorescent probes have been evaluated for the detection of hydrogen peroxide in the presence of saccharides.
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7b, a novel naphthalimide derivative, exhibited anti-inflammatory effects via targeted-inhibiting TAK1 following down-regulation of ERK1/2- and p38 MAPK-mediated activation of NF-?B in LPS-stimulated RAW264.7 macrophages.
Int. Immunopharmacol.
PUBLISHED: 05-24-2013
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Inflammatory response plays an important role not only in the normal physiology but also in the pathology such as cancers. 7b, a novel naphthalimide-based DNA intercalator, has exhibited anti-inflammatory effects in phorbol12-myristate 13-acetate/phytohemagglutinin (PMA/PHA)-induced inflammatory responses of Jurkat T cells in our previous study. Here, we tried to further investigate its anti-inflammatory potential and the possible underlying mechanisms in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and primary mouse macrophages. In our current study, ELISA and Real-time PCR revealed that non-toxic doses of 7b reduced the production and expression of pro-inflammatory cytokines, including tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?), and interleukin-6 (IL-6) in LPS-induced RAW264.7 cells and primary mouse macrophages. Moreover, 7b dose-dependently suppressed the production of prostaglandin E2 (PGE2), nitric oxide (NO). Except for COX-1, non-toxic doses of 7b exhibited parallel inhibition of LPS-induced expression of COX-2 and iNOS at both mRNA and protein levels. The molecular mechanism was associated with inhibition of the phosphorylation/degradation of I?B-? and nuclear translocation of the NF-?B p65. Further analysis of upstream mechanisms showed that blocking of NF-?B activation by 7b was mediated by inhibiting TAK1-downstream extracellular signal-regulated kinase (ERK1/2) and p38 kinase signal pathway. Taken together, these results indicated that 7b exhibited anti-inflammatory effects by targeting inhibiting TAK1, leading to ERK1/2- and p38 MAPK-mediated inactivation of NF-?B in LPS-stimulated RAW264.7 cells, and this would make 7b a strong candidate for further study as anti-inflammatory agent.
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A simple fluorescent probe for Cd2+ in aqueous solution with high selectivity and sensitivity.
Dalton Trans
PUBLISHED: 04-16-2013
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A simple quinoline-based fluorescent probe, PBQ, which contained a tweezer-like receptor, was successfully developed via one-step synthesis. PBQ exhibited a 40-fold fluorescence enhancement response to Cd(2+) in aqueous solution. PBQ was found to have excellent selectivity for Cd(2+) over many other metal ions (Ba(2+), Mn(2+), Hg(2+), Ni(2+), Ca(2+), Cu(2+), Co(2+), Pb(2+), Mg(2+), Zn(2+), Fe(2+), Fe(3+), Cr(3+), Ag(+), Li(+), Na(+), K(+)). Significantly, its fluorescence intensity was enhanced in a linear fashion with the concentration of Cd(2+). Thus PBQ can be potentially used for the quantification of Cd(2+). Moreover, a series of model compounds were rationally designed and synthesized in order to explore the binding mode of PBQ with Cd(2+).
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Induction of apoptosis and suppression of ERCC1 expression by the potent amonafide analogue 8-c in human colorectal carcinoma cells.
Anticancer Drugs
PUBLISHED: 02-22-2013
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Previous studies have reported that 8-c [6-(2-(2-(dimethylamino)ethylamino)ethylamino)-2-octyl-1H-benzo[de]isoquinoline-1,3(2H)-dione], a novel amonafide analogue, was generated as a new anticancer candidate. However, little is known about its activity in chemoresistant cells. In this study, the antitumor effects of 8-c on the multi-drug-resistant human colorectal carcinoma cancer cell lines HCT-116/L-OHP and HCT-8/VCR have been investigated for the first time. 8-c showed similar concentration-dependent inhibitory activities against multi-drug-resistant cells and corresponding parental cell lines by the MTT assay after 48 h of treatment. 8-c treatment resulted in the induction of apoptosis, as evidenced by fluorescent staining analysis, comet assay data, and the increase in the number of apoptotic cells as detected by flow cytometry. Western blot, qPCR, and siRNA techniques were used to elucidate the molecular mechanism. Our study suggested that the apoptotic effect of 8-c can be attributed to the upregulation of p53, caspase-3, and cleaved poly(ADP-ribose) polymerase (PARP) and the downregulation of Bcl-2. Furthermore, ERCC1 is essential for nucleotide excision repair. ERCC1 expression was correlated with sensitivity to chemotherapy in various colon cancer cell lines. It is intriguing that decreases in ERCC1 protein and mRNA levels were also observed in the HCT-116/L-OHP and HCT-8/VCR cells after exposure to 8-c. Further transient transfection of multi-drug-resistant cells with ERCC1 siRNA enhanced 8-c-induced cytotoxicity. In contrast, epidermal growth factor-induced increase in ERCC1 protein levels was shown to rescue cell viability upon 8-c treatment. These findings suggest that 8-c has a strong potential to be developed as a new antitumor agent for the treatment of multi-drug-resistant colon cancer cells, and is worthy of further studies.
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A novel ratiometric sensor for the fast detection of palladium species with large red-shift and high resolution both in aqueous solution and solid state.
Anal. Chim. Acta
PUBLISHED: 02-18-2013
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A highly selective fluorescent probe (OHBT) was designed and synthesized by linking the ESIPT fluorophore N-(3-(benzo[d]thiazol-2-yl)-4-(hydroxyphenyl) benzamide) (HBTBC) to the palladium specificity response group, allyl group, for the detection of palladium species in aqueous solution. The allyl group can be hydrolyzed by Pd(0) species through the Pd(0)-catalyzed Tsuji-Trost reaction and thus release the fluorophore HBTBC, which shows two emission bands. The maximum emission spectra originated from the enol and keto forms at 415 and 555 nm respectively and with no overlap, which implies the high resolution of the palladium detection. The palladium species can also be detected by paper strip because of the solid-state fluorescence of probe HOBT catalyzed by palladium. This method was successfully applied in the palladium related Suzuki-Miyaura coupling reaction and the detection limit is lower than 1 ?M.
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