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Find video protocols related to scientific articles indexed in Pubmed.
Effect of electrochemical dissolution and deposition order on lithium dendrite formation: a top view investigation.
Faraday Discuss.
PUBLISHED: 11-20-2014
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Rechargeable metallic lithium batteries are the ultimate solution to electrochemical storage due to their high theoretical energy densities. One of the key technological challenges is to control the morphology of metallic lithium electrode during electrochemical dissolution and deposition. Here we have investigated the morphology change of metallic lithium electrode after charging and discharging in nonaqueous batteries by ex situ SEM techniques from a top view. Formation of the hole structure after lithium dissolution and the filling of dendrite-like lithium into the holes has been observed for the first time. In addition, an in situ SEM investigation using an all-solid Li/Li2O/super aligned carbon nanotube set-up indicates that lithium ions could diffuse across through the surface oxide layer and grow lithium dendrites after applying an external electric field. The growth of lithium dendrites can be guided by electron flow when the formed lithium dendrite touches the carbon nanotube.
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Pharmacokinetic and Pharmacodynamic Properties of Calaspargase Pegol Escherichia coli L-Asparaginase in the Treatment of Patients With Acute Lymphoblastic Leukemia: Results From Children's Oncology Group Study AALL07P4.
J. Clin. Oncol.
PUBLISHED: 10-29-2014
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Asparaginase is a critical agent used to treat acute lymphoblastic leukemia (ALL). Pegaspargase (SS-PEG), a pegylated form of Escherichia coli L-asparaginase with a succinimidyl succinate (SS) linker, is the first-line asparaginase product used in Children's Oncology Group (COG) ALL trials. Calaspargase pegol (SC-PEG) replaces the SS linker in SS-PEG with a succinimidyl carbamate linker, creating a more stable molecule. COG AALL07P4 was designed to determine the pharmacokinetic and pharmacodynamic comparability of SC-PEG to SS-PEG in patients with newly diagnosed high-risk (HR) B-cell ALL.
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[Space-time clustering analysis of acute schistosome infections in marshland and lake areas in five provinces].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 10-28-2014
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To analyze the time and space aggregation of acute schistosome infections in marshland and lake areas in five provinces (Jiangsu, Anhui, Jiangxi, Hubei and Hunan province) from 2005 to 2012, so as to provide the evidence for establishing control strategies and taking effective control measures.
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8q24 rs4242382 Polymorphism is a Risk Factor for Prostate Cancer among Multi-Ethnic Populations: Evidence from Clinical Detection in China and a Meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
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Evidence supporting an association between the 8q24 rs4242382-A polymorphism and prostate cancer (PCa) risk has been reported in North American and Europe populations, though data from Asian populations remain limited. We therefore investigated this association by clinical detection in China, and meta-analysis in Asian, Caucasian and African-American populations.
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[Effect of plasmacytoid dendritic cells activited by bacteria on spontaneous remission of leukemia].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 10-24-2014
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Spontaneous remission (SR) of leukemia is a rare event in clinic, which possibly correlated with severe infection and sepsis, but its exact mechanism has not been confirmed. Plasmacytoid dendritic cells (pDC) and myeloid dendritic cells (mDC) play a key role in innate and adaptive immunity respectively. A patient with severe infection of staphylococcus aureus acquired completely spontaneous remission (SR), moreover a increased number of pDC were observed, suggesting that bacteria-activated pDC may play an important role in SR. This study was purposed to explore if the bacteria can stimulate pDC successfully and get a functional pDC. Both pDC and mDC were isolated from freshly collected, leukocyte-rich buffy coats from healthy blood donor and leukemic patient with SR by using MACS and FACS. The pDC were cultured in RPMI 1640 medium and were stimulated with different kinds of bacteria and the expression of CD40, CD86 and HLA-DR on the cell surface was analyzed by flow cytometry. The cytokine (IFN-?, IL-12, IFN-?, IL-2, IL-4, IL-10) production was measured by using ELISA kits. The results showed that the stimulation with staphylococcus aureus and pseudomonas aeruginosa resulted in the maturation of pDC, which secrete a large number of IFN-? and promote the differentiation of naive CD4(+) T cells to Th1 cells. The activated pDC expressed high level of CD40 and CD86 and showed higher T cell stimulatory capacities. It is concluded that staphylococcus aureus and pseudomonas aeruginosa can activate pDC, the activated pDC secrete high quantity of IFN-?. This result suggests that bacteria stimulated pDC may play a key role in SR of leukemia following severe infections.
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Biphasic regulation of autophagy by miR-96 in prostate cancer cells under hypoxia.
Oncotarget
PUBLISHED: 10-22-2014
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Autophagy favors cell survival under hypoxia, and increasing evidence revealed that microRNAs regulate autophagy. We report here hypoxia increased the expression of miR-96 in prostate cancer cells, and miR-96 stimulated autophagy by suppressing MTOR. We found that inhibition of miR-96 abolished hypoxia-induced autophagy. Paradoxically, ectopic over-expression of miR-96 to a certain threshold, also abolished the hypoxia-induced autophagy. Further studies have shown that high levels of miR-96 inhibited autophagy through suppressing ATG7, a key autophagy-associated gene. Importantly, the miR-96 expression level threshold was determined, and the effects of miR-96 on autophagy on either side of the threshold were opposite. These data demonstrate hypoxia-induced autophagy is at least partially regulated by miR-96; miR-96 can promote or inhibit autophagy by principally inhibiting MTOR or ATG7 depending on the expression levels of miR-96. Our observation might reveal a novel regulatory mode of autophagy by microRNAs under hypoxia.
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Double input capacitively coupled contactless conductivity detector with phase shift.
Anal. Chem.
PUBLISHED: 10-09-2014
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A double input capacitively coupled contactless conductivity detector (DIC(4)D) device which gets higher sensitivity has been described in this paper. The detector consists of two input electrodes and one output electrode. When two alternating current (AC) voltages with the same amplitude and different phases are imposed on each input electrode, the equivalent resistance of the output electrode is reduced because of the interference of the two signals with different phase angles. For a capacitively coupled contactless conductivity detector (C(4)D), the ratio of the response of KCl solution to that of distilled water is 1.6. However, for DIC(4)D, the ratio is 1.55 at a phase difference of 0° and increases to 1.8 at the phase difference of 170°, respectively. For C(4)D, the response of KCl solution is a linear function of the logarithm of concentrations from 10(-5) M to 10(-2) M, and the slope is 5.58. However, the slope of the response increases to 7.13 in DIC(4)D, and the limit of detection (LOD) of DIC(4)D is estimated to be 5 × 10(-8) M. The slope of the three-way DIC(4)D is increased to 69.78. A flow injection device is employed for the evaluation of the applicability of DIC(4)D with the same range, and good reproducibility is confirmed through flow injection of the same solution 10 times. The relative standard deviation (RSD) is 0.7%, which demonstrates a promising application to capillary electrophoresis (CE).
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[Evaluation and selection of VOCs treatment technologies in packaging and printing industry].
Huan Jing Ke Xue
PUBLISHED: 09-24-2014
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Volatile organic compounds (VOCs) play an important role in urban air pollution. Activities of industries including the packaging and printing industries are regarded as the major sources. How to select the suitable treating techniques is the major problem for emission control. In this article, based on the VOCs emission characteristics of the packaging and printing industry and the existing treatment technologies, using the analytic hierarchy process (AHP) model, an evaluation system for VOCs selection was established and all the technologies used for treatment were assessed. It showed that the priority selection was in the following order: Carbon Fiber Adsorption-Desorption > Granular Carbon Adsorption-Desorption > Thermal Combustion > Regenerative Combustion > Catalytic combustion > Rotary adsorption-concentration and combustion > Granular Carbon adsorption-concentration and combustion. Carbon Fiber Adsorption-Desorption was selected as the best available technology due to its highest weight among those technologies.
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Dysfunction of thermoregulation contributes to the generation of hyperthermia-induced seizures.
Neurosci. Lett.
PUBLISHED: 08-27-2014
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Febrile seizures (FS) are generally defined as seizures taking place during fever. Long-term prognosis, including development of epilepsy and malformation of cognitive function, has been demonstrated after infantile FS. However, the mechanism that triggers seizures in hyperthermic environment is still unclear. We here found that the body temperature of rat pups that experienced experimental FS was markedly decreased (?28°C) after they were removed from the hyperthermic environment. Both the seizure generation and the temperature drop after seizure attack were abolished by either pre-treatment with chlorpromazine (CPZ), which impairs the thermoregulation, or by an electrolytic lesion of the preoptic area and anterior hypothalamus (PO/AH). However, the non-steroidal anti-inflammatory drug celecoxib did not affect the seizure incidence and the decrease in body temperature after seizure attack. In addition, pentobarbital prevented the generation of seizures, but did not reverse the decrease of body temperature after FS. Therefore, our work indicates that an over-regulation of body temperature occurs during hyperthermic environment, and that the dysfunction of thermoregulation in the PO/AH following hyperthermia contributes to the generation of FS.
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Highly double selective nitration of nitrostilbenes over zeolite.
Chem. Commun. (Camb.)
PUBLISHED: 08-01-2014
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A feasible zeolite-assisted ortho C-H nitration of nitrostilbenes has been developed for the first time, which can be used in situ. It uses acetyl nitrate as a mild, easily handled and commercially available nitrating reagent, leading to the synthesis of polynitrostilbenes with double selectivities and in good yields.
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[Effect of the lysine guanidination on proteomic analysis].
Se Pu
PUBLISHED: 07-30-2014
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The guanidination of lysine side chain was paid great attention in recent years. It plays an important role in qualitative and quantitative proteomics. In this study, based on the results of separated peptides extracted from HeLa cells before and after the guanidination by liquid chromatography-tandem mass spectrometry (LC-MS/MS), the effect of the guanidination of three different kinds of peptides was systematically analyzed. It was found that the selectivity of the guanidination of the lysine side chain was as high as 96.8%. The ratio of identified peptides with lysine at C-term to all peptides increased from 51.7% to 57.3% and more new peptides were identified, while the ratio of peptides with lysine in the middle or without lysine changed little. Further study on the ratio of b and y ions indicated that there were more y ions of peptides with lysine at C-term after the guanidination. The results proved that the selective conversion of lysine to homoarginine by the guanidination could increase the sensitivity and selectivity of mass spectrum. The increased basicity and ability to sequester proton of lysine produced more y ions fragmentation information, which contributed to more identified peptides. It concluded that the lysine guanidination can improve the coverage of proteomic analysis.
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[Selective catalytic oxidation of H2S over supported fe catalysts on CeO2-intercalated laponite clay].
Huan Jing Ke Xue
PUBLISHED: 07-25-2014
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A series of Fe/CeO2-intercalated clay catalysts were synthesized successfully, the physicochemical properties of the catalysts were characterized by XRD, BET, XRF, TG, FT-IR, O2-TPD, H2-TPR and XPS methods. The catalytic performances for selective catalytic oxidation of H2S were further investigated, all catalysts exhibited high catalytic activities. Among them 5% Fe/Ce-Lap presented the best activity at 180 degreeC and the maximum sulfur yield was up to 96% due to the interaction between iron and cerium, which improved the redox ability of Fe3+ . Moreover, the strong oxygen adsorption capacity and the well dispersion of iron species improved the catalytic performance efficiently.
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Copper catalyzed C-O bond formation via oxidative cross-coupling reaction of aldehydes and ethers.
Org. Biomol. Chem.
PUBLISHED: 07-18-2014
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A practical and efficient construction of C-O bonds via oxidative cross-coupling reaction of aldehydes and ethers has been realized under open air. When 2 mol% copper was used as the catalyst, various ?-acyloxy ethers were obtained with up to 93% isolated yield.
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Host miR-26a suppresses replication of porcine reproductive and respiratory syndrome virus by upregulating type I interferons.
Virus Res.
PUBLISHED: 07-10-2014
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MicroRNAs (miRNAs) play important roles in viral infections, especially by modulating the expression of cellular factors essential to viral replication or the host innate immune response to infection. To identify host miRNAs important to controlling porcine reproductive and respiratory syndrome virus (PRRSV) infection, we screened 15 miRNAs that were previously implicated in innate immunity or antiviral functions. Over-expression of the miR-26 family strongly inhibited PRRSV replication in vitro, as shown by virus titer assays, Western blotting, and qRT-PCR assays. MiR-26a inhibited the replication of both type 1 and type 2 PRRSV strains. Mutating the seed region of miR-26 restored viral titers. Luciferase reporters showed that miR-26a does not target the PRRSV genome directly but instead affects the expression of type I interferon and the IFN-stimulated genes MX1 and ISG15 during PRRSV infection. These results demonstrate the important role of miR-26a in modulating PRRSV infection and also support the possibility of using host miR-26a to achieve RNAi-mediated antiviral therapeutic strategies.
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Hepatic inflammation scores correlate with common carotid intima-media thickness in rats with NAFLD induced by a high-fat diet.
BMC Vet. Res.
PUBLISHED: 07-09-2014
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Non-alcoholic fatty liver disease (NAFLD), an emerging public health problem, may be a highly atherogenic condition. But the relationship between fatty liver diseases and carotid atherosclerosis in small-animal is incompletely understood. The purpose of the present study was to evaluate carotid intima-media thickness (IMT) in NAFLD rats using high-frequency ultrasonic diagnostic equipment, and to ascertain if the degree of hepatic pathological changes was associated with carotid IMT.
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New insight in understanding oxygen reduction and evolution in solid-state lithium-oxygen batteries using an in situ environmental scanning electron microscope.
Nano Lett.
PUBLISHED: 07-07-2014
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Via designing a facile microscale all-solid-state lithium-oxygen battery system constructed in an environmental scanning electron microscope, direct visualization of discharge and charge processes of the lithium-oxygen battery is achieved. Different morphologies of the discharge product are observed, including a sphere, conformal film, and red-blood-cell-like shape, with a particle size up to 1.5 ?m; whereas upon charge, the decomposition initiates at their surface and continues along a certain direction, instead of from the contact point at the electrode. These new findings indicate that the electron and lithium ion conductivities of Li2O2 could support the growth and decomposition of the discharge product in our system. In addition, our results indicate that various morphologies of Li2O2 arise from the different current density and surface chemistry of CNT, and the growth and decomposition of the particle are related to the uneven distribution of the ionic and electronic conductivities of Li2O2.
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Round pneumonia in an adult.
Southeast Asian J. Trop. Med. Public Health
PUBLISHED: 06-27-2014
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Round pneumonia is an uncommon form of pulmonary infection usually found in children. It may resemble pulmonary neoplasm on radiographs. We present a case of round pneumonia in a 43-year-old male with a history of smoking and a family history of lung cancer. The patient was treated with antibiotics for more than two weeks, after which the infection resolved completely both clinically and radiologically. Clinicians should consider this uncommon type of pneumonia in the differential diagnosis of spherical pulmonary masses to avoid unnecessary diagnostic tests.
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Voltammetric determination of TBHQ at a glassy carbon electrode surface activated by in situ chemical oxidation.
Analyst
PUBLISHED: 06-03-2014
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In this article, a bare glassy carbon electrode (GCE) surface was directly activated by a simple in situ chemical method, which was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). Based on these results, it was found that oxygen-containing functional groups at the modified GCE surface were enhanced with a low damage to the surface state. Hence, the modified GCE exhibited an excellent performance, such as the negatively charged surface, good reproducibility and high selectivity. The resulting electrode was applied as a sensitive sensor for detection of antioxidant tertiary butyl hydroquinone (TBHQ), and a good linear relationship was obtained between the oxidation peak current and the concentration in a broad range of 1.0 ?M-1.1 mM, with detection limits of 67 nM (S/N = 3) by DPV. Electrochemical parameters of TBHQ on the resulting GCE were also investigated, suggesting that the modified GCE could promote electron transfer kinetics towards the electrochemical reaction of TBHQ. Besides, the present method was used for determination of TBHQ in jatropha biodiesel with recovery ranging from 95.2% to 103.2%.
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3D visualization of inhomogeneous multi-layered structure and Young's modulus of the solid electrolyte interphase (SEI) on silicon anodes for lithium ion batteries.
Phys Chem Chem Phys
PUBLISHED: 05-30-2014
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The microstructure and mechanical properties of the solid electrolyte interphase (SEI) in non-aqueous lithium ion batteries are key issues for understanding and optimizing the electrochemical performance of lithium batteries. In this report, the three-dimensional (3D) multi-layered structures and the mechanical properties of the SEI formed on a silicon anode material for next generation lithium ion batteries have been visualized directly for the first time, through a scanning force spectroscopy method. The coverage of the SEI on silicon anodes is also obtained through 2D projection plots. The effects of temperature and the function of additives in the electrolyte on the SEI can be understood accordingly. A modified model about dynamic evolution of the SEI on the silicon anode material is also proposed, which aims to explain why the SEI is very thick and how the multi-layered structure is formed and decomposed dynamically.
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Reduction patterns of acute schistosomiasis in the People's Republic of China.
PLoS Negl Trop Dis
PUBLISHED: 05-01-2014
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Despite significant, steady progress in schistosomiasis control in the People's Republic of China over the past 50 years, available data suggest that the disease has re-emerged with several outbreaks of acute infections in the early new century. In response, a new integrated strategy was introduced.
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[Identification of radix et rhizoma clematidis and its adulterants using DNA barcoding].
Yao Xue Xue Bao
PUBLISHED: 04-26-2014
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This study provides the candidate sequences in the identification of Radix et Rhizoma Clematidis and its adulterants using DNA barcoding. We amplified and sequenced the region psbA-trnH, with the data of 284 sequences from GenBank, the differential intra- and inter-specific divergences, genetic distance, barcoding gap were used to evaluate five barcodes, and the identification efficiency was assessed using BLAST1 and Nearest Distance methods. The results showed that psbA-trnH barcodes performed high identification efficiency and inter-specific divergences among the five different DNA barcodes. Analysis of the barcoding gap and NJ tree showed psbA-trnH was superior to other barcodes. Based on the identification and PCR amplification efficiency, psbA-trnH can be the ideal barcode to identify Radix et Rhizoma Clematidis and its adulterants accurately.
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Synthesis and electrochemical properties of spinel LiMn1.95M(x)O(4-y)F(y) for lithium ion batteries.
J Nanosci Nanotechnol
PUBLISHED: 04-25-2014
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Spinel phase LiMn1.95M(x)O(4-y)F(y) (M = Co and Y) were prepared by a rheological phase reaction method. The samples were characterized by X-ray diffraction, scanning electron microscopy, AC impedance, and galvanostatic charge/discharge profile measurement. These results showed that the LiMn1.95M(x)O(4-y)F(y) had better cycling performance than pure LiMn2O4. Among all the doped samples, the LiMn1.95Co0.03Y0.02O3.96F0.04 sample showed the best cycling performance, the initial discharge capacitiy is 129 mAh/g, and the discharge capacity of 124 mAh/g at a rate of 0.5 C after 50 cycles. The loss of its capacity was only 3.4%. The possible reasons for the outstanding electrochemical properties of LiMn1.95Co0.03Y0.02O3.96F0.04 are also discussed.
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Synthesis and electrochemical properties of SnWO4.
J Nanosci Nanotechnol
PUBLISHED: 04-22-2014
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In this paper, a pure SnWO4 was synthesized by solvothermal method. The glucose as a carbon sources was mixed with SnWO4 to prepared SnWO4/C composite. The structure and morphology were characterized by XRD and SEM techniques. The electrochemical properties of SnWO4 and SnWO4/C composite were studied by battery comprehensive testing system and AC impedance spectroscopy. The results showed that the alpha-SnWO4 phase was formed and its particles were ranged from 50 to 250 nm. The alpha-SnWO4/C composites behaved higher reversible discharge capacity and better cycle performance than that of alpha-SnWO4. The reversible discharge capacity of SnWO4/C composites was 780 mA h/g at the current density (50 mA/g) and it could keep at 600 mA h/g after 30 cycles. The reason for SnWO4/C composite to behave outstanding electrochemical properties was discussed also.
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[Fe-ZSM-5 catalysts with different silica-alumina ratios for N2O, catalytic decomposition].
Huan Jing Ke Xue
PUBLISHED: 04-12-2014
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The Fe-ZSM-5 catalysts were prepared with H-ZSM-5 of different Si/Al ratios by wet ion exchange and chemical vapor deposition. Then the catalysts were investigated by XRD, BET, TEM, UV-vis and NH3-TPD technologies to analyze the iron states in Fe-ZSM-5 zeolites. The results showed that after H-ZSM-5 zeolites were prepared by chemical vapor deposition and heating wet ion exchange, the nano Fe2 O3 particles were uniformly dispersed with the sizes of 8 nm in the Fe-ZSM-5-25 (Si/A1-25). Moreover, there were more oligonuclear Fe3+ Oy clusters in the Fe-ZSM-5-25 catalysts than in Fe-ZSM-5-300 (Si/Al-300). The results of catalytic performance on N2O decomposition showed that Fe-ZSM-5-25 catalysts had higher catalytic activities than Fe-ZSM-5-300 catalysts. The Fe-ZSM-5 catalysts prepared by chemical vapor deposition achieved the best catalytic activity in N2O decomposition among the catalysts prepared by the three methods. Moreover, the presence of O2 only slightly reduced N2O conversion, while NO promoted the N2O decomposition. Finally, after reaction for more than 100 h, Fe-ZSM-5 catalyst showed no obvious deactivation under simulated emission conditions.
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Standardization in patient safety: the WHO High 5s project.
Int J Qual Health Care
PUBLISHED: 04-10-2014
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Despite its success in other industries, process standardization in health care has been slow to gain traction or to demonstrate a positive impact on the safety of care.
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Genomic characterization of a bovine viral diarrhea virus 1 isolate from swine.
Arch. Virol.
PUBLISHED: 03-21-2014
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The SD0803 strain of the bovine viral diarrhea virus (BVDV) was isolated from a piglet in China in 2008 and has been classified as a novel subgenotype of BVDV-1. To describe the molecular features of this novel subgenotype, we sequenced and characterized the complete genome of the SD0803 virus. The genome is 12,271 bp in length and contains 5' and 3' untranslated regions (UTRs) that flank an open reading frame (ORF) encoding a 3,898-amino-acid polypeptide. The full-length genome of the SD0803 strain shares 78.8% to 83.3% identity with those of other BVDV-1 strains, 70.0% to 70.7% identity with those of BVDV-2 strains, and less than 67.6% identity with those of other pestiviruses. The highest level of shared identity was 83.3% between the complete SD0803 genome and that of the ZM-95 strain of BVDV-1. Phylogenetic analysis of the 5' UTR and the coding sequence for the N-terminal protease fragment of the SD0803 polyprotein indicated that the SD0803 virus is a member of the novel subgenotype BVDV-1q, isolates of which have been identified recently in dairy cattle and camels in China.
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Downregulation of COX-2 and CYP 4A signaling by isoliquiritigenin inhibits human breast cancer metastasis through preventing anoikis resistance, migration and invasion.
Toxicol. Appl. Pharmacol.
PUBLISHED: 03-17-2014
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Flavonoids exert extensive in vitro anti-invasive and in vivo anti-metastatic activities. Anoikis resistance occurs at multiple key stages of the metastatic cascade. Here, we demonstrate that isoliquiritigenin (ISL), a flavonoid from Glycyrrhiza glabra, inhibits human breast cancer metastasis by preventing anoikis resistance, migration and invasion through downregulating cyclooxygenase (COX)-2 and cytochrome P450 (CYP) 4A signaling. ISL induced anoikis in MDA-MB-231 and BT-549 human breast cancer cells as evidenced by flow cytometry and the detection of caspase cleavage. Moreover, ISL inhibited the mRNA expression of phospholipase A2, COX-2 and CYP 4A and decreased the secretion of prostaglandin E2 (PGE2) and 20-hydroxyeicosatetraenoic acid (20-HETE) in detached MDA-MB-231 cells. In addition, it decreased the levels of phospho-PI3K (Tyr(458)), phospho-PDK (Ser(241)) and phospho-Akt (Thr(308)). Conversely, the exogenous addition of PGE2, WIT003 (a 20-HETE analog) and an EP4 agonist (CAY10580) or overexpression of constitutively active Akt reversed ISL-induced anoikis. ISL exerted the in vitro anti-migratory and anti-invasive activities, whereas the addition of PGE2, WIT003 and CAY10580 or overexpression of constitutively active Akt reversed the in vitro anti-migratory and anti-invasive activities of ISL in MDA-MB-231 cells. Notably, ISL inhibited the in vivo lung metastasis of MDA-MB-231 cells, together with decreased intratumoral levels of PGE2, 20-HETE and phospho-Akt (Thr(308)). In conclusion, ISL inhibits breast cancer metastasis by preventing anoikis resistance, migration and invasion via downregulating COX-2 and CYP 4A signaling. It suggests that ISL could be a promising multi-target agent for preventing breast cancer metastasis, and anoikis could represent a novel mechanism through which flavonoids may exert the anti-metastatic activities.
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Arsenic mobilization in aquifers of the southwest Songnen basin, P.R. China: evidences from chemical and isotopic characteristics.
Sci. Total Environ.
PUBLISHED: 03-17-2014
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High As groundwater has widely been found in the inland basins of China. Little is known about distribution and mobilization mechanisms of high As groundwater in the Songnen basin, where groundwater is the major source for drinking and irrigation. Eighty-seven groundwater samples, three surface water samples and sixty-three sediment samples were taken from the southwest of the Songnen basin, in order to investigate spatial distribution and constrains of groundwater As. Results showed that high As groundwater was generally of Na-Mg/Ca-HCO3 type, which had relatively low Eh values and neutral-weakly alkaline pH. High As groundwater was characterized by low concentrations of NO3(-) and SO4(2-), and high concentrations of Fe, Mn, and H2S. Around 65.5% of sampled shallow groundwater and 96% of sampled deep groundwater had As concentrations greater than 10 ?g/L. Sediments had higher total As contents and higher Fe/Mn oxide-bound As contents in high As groundwater area than in the low As groundwater area. Distribution of groundwater As was dependent upon hydrogeologic settings, redox potential, microbial degradation of organic carbon, and precipitation of pyrite, siderite, and calcite. Along the groundwater flow path, As concentration showed an increasing trend. High As groundwater was mainly distributed in the low-lying areas. Reducing conditions were the major causes for As mobilization in the aquifers, which led to more As released from the sediments with higher contents of Fe/Mn oxide-bound As in higher As groundwater area. Results of (13)CDOC and (13)CDIC showed that dissimilatory Fe(III) reduction coupled with microbial degradation of dissolved organic carbon would be related to As mobilization in the aquifers. Although both Fe and As were released during these redox processes, pyrite, siderite and calcite precipitation would be the sink of dissolved As, which resulted in weak correlation between dissolved Fe and As.
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Gender difference in acquired seizure susceptibility in adult rats after early complex febrile seizures.
Neurosci Bull
PUBLISHED: 03-11-2014
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Gender differences are involved in many neurological disorders including epilepsy. However, little is known about the effect of gender difference on the risk of epilepsy in adults with a specific early pathological state such as complex febrile seizures (FSs) in infancy. Here we used a well-established complex FS model in rats and showed that: (1) the susceptibility to seizures induced by hyperthermia, pentylenetetrazol (PTZ), and maximal electroshock (MES) was similar in male and female rat pups, while males were more susceptible to PTZ- and MES-induced seizures than age-matched females in normal adult rats; (2) adult rats with complex FSs in infancy acquired higher seizure susceptibility than normal rats; importantly, female FS rats were more susceptible to PTZ and MES than male FS rats; and (3) the protein expression of interleukin-1?, an inflammatory factor associated with seizure susceptibility, was higher in adult FS females than in males, which may reflect a gender-difference phenomenon of seizure susceptibility. Our results provide direct evidence that the acquired seizure susceptibility after complex FSs is gender-dependent.
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Association of a single nucleotide polymorphism in HOXB9 with developmental dysplasia of the hip: a case-control study.
J. Orthop. Res.
PUBLISHED: 03-07-2014
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Developmental dysplasia of the hip (DDH) is one of the most common skeletal disorders. It comprises a spectrum of abnormalities, including shallow acetabulum and decreased coverage of the femoral head. Genetic component plays a considerable role in the aetiology of DDH. HOXB9 may be involved in the aetiology and pathogenesis of DDH, as it plays an important role in the development of the limbs. Our objective was to evaluate whether single nucleotide polymorphisms (SNPs) of HOXB9 (rs2303486 and rs8844) were associated with DDH in Chinese population. The HOXB9 tag SNPs were genotyped in 460 DDH cases and 562 control subjects by Taqman assay, and their association was examined. rs8844 was not associated with DDH. rs2303486 was associated with DDH in the dominant genetic model (p = 0.037; odds ratio (OR) = 1.32; 95% confidence interval (CI) = 1.02–1.71). After stratification by sex, significant association of the dominant genetic model still existed in the female subjects (p = 0.015; OR = 1.46; 95% CI = 1.08–1.98),but not in the male subjects. After stratification by severity, we discovered an association with hip dislocation in the dominant model(p=0.042; OR = 1.35; 95% CI = 1.01–1.80), but not with subluxation or instability. HOXB9 is associated with DDH in Chinese.
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Phase behavior of ovalbumin and carboxymethylcellulose composite system.
Carbohydr Polym
PUBLISHED: 03-03-2014
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The phase behavior, rheological properties and microstructure of ovalbumin and carboxymethylcellulose (OVA-CMC) conjugates were studied and the influence parameters were investigated. The results showed that the phase behavior of OVA-CMC conjugates was related to pH and concentration of CMC and NaCl. When pH was over 5.0, discrete phase separation occurred in the mixture system, which indicated that OVA and CMC were thermodynamic incompatible. The mixture system turned into uniform stable emulsion system when pH reduced below 5.0. The addition of NaCl can improve the stability of composite system against pH sensitivity. CLSM and particle size distribution and ultraviolet spectrum analysis results confirm that emptying interactions play a leading role in the separation system.
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HLA-DR polymorphism and primary biliary cirrhosis: evidence from a meta-analysis.
Arch. Med. Res.
PUBLISHED: 02-26-2014
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We undertook this study to review and quantitatively analyze the association between human leukocyte antigen (HLA) DR polymorphisms and susceptibility of primary biliary cirrhosis (PBC).
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Genetic manipulation of a transcription-regulating sequence of porcine reproductive and respiratory syndrome virus reveals key nucleotides determining its activity.
Arch. Virol.
PUBLISHED: 02-23-2014
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The factors that determine the transcription-regulating sequence (TRS) activity of porcine reproductive and respiratory syndrome virus (PRRSV) remain largely unclear. In this study, the effect of mutagenesis of conserved C nucleotides at positions 5 and 6 in the leader TRS (TRS-L) and/or canonical body TRS7 (TRS-B7) on the synthesis of subgenomic (sg) mRNA and virus infectivity was investigated in the context of a type 2 PRRSV infectious cDNA clone. The results showed that a double C mutation in the leader TRS completely abolished sg mRNAs synthesis and virus infectivity, but a single C mutation did not. A single C or double C mutation in TRS-B7.1 or/and TRS-B7.2 impaired or abolished the corresponding sg mRNA synthesis. Introduction of identical mutations in the leader and body TRSs partially restored sg mRNA7.1 and/or sg mRNA7.2 transcription, indicating that the base-pairing interaction between sense TRS-L and cTRS-B is a crucial factor influencing sg mRNA synthesis. Analysis of the mRNA leader-body junctions of mutants provided evidence for a mechanism of discontinuous minus-strand transcription. This study also showed that mutational inactivation of TRS-B7.1 or TRS-B7.2 did not affect the production of infectious progeny virus, and the sg mRNA formed from each of them could express N protein. However, TRS-B7.1 plays more important roles than TRS-B7.2 in maintaining the growth characteristic of type 2 PRRSV. These results provide more insight into the molecular mechanism of genome expression and subgenomic mRNA transcription of PRRSV.
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Reversible hyperphagia and obesity in rats with gastric bypass by central MC3/4R blockade.
Obesity (Silver Spring)
PUBLISHED: 02-12-2014
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To test the commonly held assumption that gastric bypass surgery lowers body weight because it limits the ability to eat large amounts of food.
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A replication study for the association of rs726252 in PAPPA2 with developmental dysplasia of the hip in Chinese Han population.
Biomed Res Int
PUBLISHED: 02-03-2014
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Developmental dysplasia of the hip (DDH) is a common developmental hip disorder, which ranges from mild acetabulum malformation to irreducible hip dislocation. A previous study suggested a significant association of pregnancy-associated plasma protein-A2 (PAPPA2) with DDH susceptibility in Chinese Han population. But with the consideration of the sample size, the association was still debatable. To confirm the association of the reported single nucleotide polymorphism (SNP) in PAPPA2, rs726252 with DDH, we conducted a case-control study in a larger number of subjects. We genotyped rs726252 in 697 DDH subjects and 707 control subjects by TaqMan assay. The association between this SNP and DDH was evaluated statistically. No significant difference was found in any comparison of genotype distribution nor allele frequency between cases and controls. Our replication study indicated that the association between rs726252 and DDH in Chinese Han population was debatable. The association between PAPPA2 and DDH should be evaluated by additional studies.
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The Fusion Protein of CTP-HBcAg18-27-Tapasin Mediates the Apoptosis of CD8(+)T Cells and CD8(+) T Cell Response in HLA-A2 Transgenic Mice.
Hepat Mon
PUBLISHED: 02-01-2014
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HBV-specific cytotoxic T lymphocyte (CTL) activity is believed to play a critical role in controlling HBV infection. The phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway manipulates cell fate decisions in many different cell types by regulating the activity of downstream effectors. We have previously testified that the fusion protein of CTP-HBcAg18-27--Tapasin could enter the cytoplasm of dendritic cells and efficiently induce robust specific CTL response in vitro.
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GLP-1 receptor signaling is not required for reduced body weight after RYGB in rodents.
Am. J. Physiol. Regul. Integr. Comp. Physiol.
PUBLISHED: 01-15-2014
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Exaggerated GLP-1 and PYY secretion is thought to be a major mechanism in the reduced food intake and body weight after Roux-en-Y gastric bypass surgery. Here, we use complementary pharmacological and genetic loss-of-function approaches to test the role of increased signaling by these gut hormones in high-fat diet-induced obese rodents. Chronic brain infusion of a supramaximal dose of the selective GLP-1 receptor antagonist exendin-9-39 into the lateral cerebral ventricle significantly increased food intake and body weight in both RYGB and sham-operated rats, suggesting that, while contributing to the physiological control of food intake and body weight, central GLP-1 receptor signaling tone is not the critical mechanism uniquely responsible for the body weight-lowering effects of RYGB. Central infusion of the selective Y2R-antagonist BIIE0246 had no effect in either group, suggesting that it is not critical for the effects of RYGB on body weight under the conditions tested. In a recently established mouse model of RYGB that closely mimics surgery and weight loss dynamics in humans, obese GLP-1R-deficient mice lost the same amount of body weight and fat mass and maintained similarly lower body weight compared with wild-type mice. Together, the results surprisingly provide no support for important individual roles of either gut hormone in the specific mechanisms by which RYGB rats settle at a lower body weight. It is likely that the beneficial effects of bariatric surgeries are expressed through complex mechanisms that require combination approaches for their identification.
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Accumulation and fraction distribution of Ni(II) in activated sludge treating Ni-laden wastewater.
Environ Sci Pollut Res Int
PUBLISHED: 01-09-2014
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The accumulation and fraction distribution of Ni(II) in sludge was determined, and their effect on the performance of sequencing batch reactor (SBR) systems was evaluated at laboratory scale. The results showed that the removal efficiencies of substrates decreased significantly with increasing feeding concentration of Ni(II) into SBRs. The concentration of Ni(II) fed into the SBRs was significantly positively correlated with the Ni(II) contents accumulated in the sludge, while it was negatively correlated with the biomass in the SBRs. The accumulated Ni(II) in the sludge was distributed mainly in the available fraction, accounting for 75.8-90.0 % of the total Ni(II) content. The accumulated content of Ni(II) in each sludge fraction could be predicted satisfactorily by the feeding Ni(II) concentrations in the solutions. As compared with the total contents and other chemical fractions, Ni(II) in the oxidizable fraction in sludge exhibited more important inhibition effects on sludge microorganisms in the SBRs.
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CAV-1 contributes to bladder cancer progression by inducing epithelial-to-mesenchymal transition.
Urol. Oncol.
PUBLISHED: 01-07-2014
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The epithelial-to-mesenchymal transition (EMT) is a critical step in tumor metastasis. CAV-1 has been shown to be an oncogene in bladder cancer. However, little is known about the relationship between CAV-1 and EMT in bladder cancer metastasis.
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Tuning the electron transport at single donors in zinc oxide with a scanning tunnelling microscope.
Nat Commun
PUBLISHED: 01-07-2014
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In devices like the single-electron transistor the detailed transport properties of a nanostructure can be measured by tuning its energy levels with a gate voltage. The scanning tunnelling microscope in contrast usually lacks such a gate electrode. Here we demonstrate tuning of the levels of a donor in a scanning tunnelling microscope without a third electrode. The potential and the position of the tip are used to locally control band bending. Conductance maps in this parameter space reveal Coulomb diamonds known from three-terminal data from single-electron transistors and provide information on charging transitions, binding energies and vibrational excitations. The analogy to single-electron transistor data suggests a new way of extracting these key quantities without making any assumptions about the unknown shape of the scanning tunnelling microscope tip.
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Analysis of Five Earthy-Musty Odorants in Environmental Water by HS-SPME/GC-MS.
Int J Anal Chem
PUBLISHED: 01-02-2014
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The pressing issue of earthy and musty odor compounds in natural waters, which can affect the organoleptic properties of drinking water, makes it a public health concern. A simple and sensitive method for simultaneous analysis of five odorants in environmental water was developed by headspace solid-phase microextraction (HS-SPME) coupled to chromatography-mass spectrometry (GC-MS), including geosmin (GSM) and 2-methylisoborneol (2-MIB), as well as dimethyl trisulfide (DMTS), ? -cyclocitral, and ? -ionone. Based on the simple modification of original magnetic stirrer purchased from CORNING (USA), the five target compounds can be separated within 23?min, and the calibration curves show good linearity with a correlation coefficient above 0.999 (levels?=?5). The limits of detection (LOD) are all below 1.3?ng?L(-1), and the relative standard deviation (%RSD) is between 4.4% and 9.9% (n = 7) and recoveries of the analytes from water samples are between 86.2% and 112.3%. In addition, the storage time experiment indicated that the concentrations did not change significantly for GSM and 2-MIB if they were stored in canonical environment. In conclusion, the method in this study could be applied for monitoring these five odorants in natural waters.
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Educating future leaders in patient safety.
J Multidiscip Healthc
PUBLISHED: 01-01-2014
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Education of health care professionals has given little attention to patient safety, resulting in limited understanding of the nature of risk in health care and the importance of strengthening systems. The World Health Organization developed the Patient Safety Curriculum Guide: Multiprofessional Edition to accelerate the incorporation of patient safety teaching into higher educational curricula. The World Health Organization Curriculum Guide uses a health system-focused, team-dependent approach, which impacts all health care professionals and students learning in an integrated way about how to operate within a culture of safety. The guide is pertinent in the context of global educational reforms and growing recognition of the need to introduce patient safety into health care professionals' curricula. The guide helps to advance patient safety education worldwide in five ways. First, it addresses the variety of opportunities and contexts in which health care educators teach, and provides practical recommendations to learning. Second, it recommends shared learning by students of different professions, thus enhancing student capacity to work together effectively in multidisciplinary teams. Third, it provides guidance on a range of teaching methods and pedagogical activities to ensure that students understand that patient safety is a practical science teaching them to act in evidence-based ways to reduce patient risk. Fourth, it encourages supportive teaching and learning, emphasizing the need to establishing teaching environments in which students feel comfortable to learn and practice patient safety. Finally, it helps educators incorporate patient safety topics across all areas of clinical practice.
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miR-21 induces cell proliferation and suppresses the chemosensitivity in glioblastoma cells via downregulation of FOXO1.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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miR-21 shares a potential oncogenic function. The overexpression of miR-21 was common in glioblastoma, which is the most common lethal primary intracranial tumor. The study aimed at miR-21 effect on Glioblastoma cell line A172 of proliferation, apoptosis, and chemosensitivity and its definite mechanism of target gene FOXO1. Effect and mechanism were evaluated by colony forming cell assay, annexin V-FITC/PI apoptosis assay, TUNEL apoptosis assay, luciferase-reporter activities assay, RNA interference, western-blot and Real-Time PCR. The statistics revealed miR-21 promoted A172 cell proliferation and suppressed the chemosensitivity, and also showed that miR-21 could bind with FOXO1 mRNA and prevent FOXO1 translation via its 3'UTR to regulate the function. These findings suggest that miR-21 plays an important role in cell proliferation and chemosensitivity by inhibiting FOXO1, and show much more significance for exploring miR-21 inhibitor in A172 therapy.
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Renal tissue thawed for 30 minutes is still suitable for gene expression analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Some biosamples obtained from biobanks may go through thawing before processing. We aim to evaluate the effects of thawing at room temperature for different time periods on gene expression analysis. A time course study with four time points was conducted to investigate the expression profiling on 10 thawed normal mice renal tissue samples through Affymetrix GeneChip mouse gene 2.0 st array. Microarray results were validated by quantitative real time polymerase chain reactions (qPCR) on 6 candidate reference genes and 11 target genes. Additionally, we used geNorm plus and NormFinder to identify the most stably expressed reference genes over time. The results showed RNA degraded more after longer incubation at room temperature. However, microarray results showed only 240 genes (0.91%) altered significantly in response to thawing at room temperature. The signal of majority altered probe sets decreased with thawing time, and the crossing point (Cp) values of all candidate reference genes correlated positively with the thawing time (p<0.05). The combination of B2M, ACTB and PPIA was identified as the best choice for qPCR normalization. We found most target genes were stable by using this normalization method. However, serious gene quantification errors were resulted from improper reference genes. In conclusion, thirty minutes of thawing at room temperature has a limited impact on microarray and qPCR analysis, gene expression variations due to RNA degradation in early period after thawing can be largely reduced by proper normalization.
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Comprehensive Phylogenetic Diversity of [FeFe]-Hydrogenase Genes in Termite Gut Microbiota.
Microbes Environ.
PUBLISHED: 11-15-2013
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Phylogenetic diversity of [FeFe]-hydrogenase (HydA) in termite guts was assessed by pyrosequencing PCR amplicons obtained using newly designed primers. Of 8,066 reads, 776 hydA phylotypes, defined with 97% nucleotide sequence identity, were recovered from the gut homogenates of three termite species, Hodotermopsis sjoestedti, Reticulitermes speratus, and Nasutitermes takasagoensis. The phylotype coverage was 92-98%, and the majority shared only low identity with database sequences. It was estimated that 194-745 hydA phylotypes existed in the gut of each termite species. Our results demonstrate that hydA gene diversity in the termite gut microbiota is much higher than previously estimated.
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[Research progress on biochar carbon sequestration technology].
Huan Jing Ke Xue
PUBLISHED: 11-07-2013
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Biochar is a fine-grained and porous material, which is produced by pyrolyzing biomass under anaerobic or oxygen-limiting condition. Due to the aromatic structure, it is resistant to the biotic and abiotic degradation which makes biochar production a promising carbon sequestration technology, and it has attracted widespread attention. Factors including biochar production, biochar stability in soil and the response of plant growth and soil organic carbon to the biochar addition can influence the carbon sequestration potential of biochar. Through exploring the mechanisms of biochar carbon sequestration, the influence of these factors was studied. Furthermore, the research progress of carbon sequestration potential and its economic viability were examined. Finally, aiming at the knowledge gaps in the influencing factors as well as the relationship between these factors, some further research needs were proposed for better application of biochar in China.
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Sleeve muscle actuator and its application in transtibial prostheses.
IEEE Int Conf Rehabil Robot
PUBLISHED: 11-05-2013
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This paper describes the concept of a new sleeve muscle actuator, and a transtibial prosthesis design powered by this novel actuator. Inspired by the functioning mechanism of the traditional pneumatic muscle actuator, the sleeve muscle actuator incorporates a cylindrical insert to the center of the pneumatic muscle, which eliminates the central portion of the internal volume. As a result of this change, the sleeve muscle provides multiple advantages over the traditional pneumatic muscle, including the increased force capacity over the entire range of motion, reduced energy consumption, and faster dynamic response. Furthermore, utilizing the load-bearing tube as the insert, the sleeve muscle enables an innovative "actuation-load bearing" structure, which has a potential of generating a highly compact actuation system suitable for prosthetic use. Utilizing this new actuator, the preliminary design of a transtibial prosthesis is presented, which is able to provide sufficient torque output and range of motion for a 75 Kg amputee user in level walking.
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Electrochemical performances and volume variation of nano-textured silicon thin films as anodes for lithium-ion batteries.
Nanotechnology
PUBLISHED: 09-25-2013
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Electrochemical behaviors of nano-textured silicon thin film (NTSTF) coated with Al2O3 or Cu layers as anodes for lithium-ion batteries have been investigated. The cyclic performance of NTSTF electrodes is superior to dense Si thin films. The NTSTF with a 5 nm thick Cu coating layer shows superior cyclic performance and rate performance to other NTSTF samples. The volume changes of NTSTF electrodes after the first cycle and the tenth cycle have been investigated. This series of electrodes shows an anisotropic volume variation: the height does not change but the diameter does expand. This finding shows the feasibility of dealing with the vertical expansion and contraction of Si-based powder electrodes in Li-ion batteries.
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Graphical assessment of consistency in treatment effect among countries in multi-regional clinical trials.
Clin Trials
PUBLISHED: 09-06-2013
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One key objective of a multi-regional clinical trial (MRCT) is to use the trial results to bridge from the global level to local region in support of local registrations. However, data from each individual country are typically limited and the large number of countries will increase the chance of false positive findings.
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[Alterations of Cajal cells in the colon of slow transit constipation rats].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 08-28-2013
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To investigate the association of expression of c-kit (marker of interstitial cells of Cajal, ICC) in colon with slow transit constipation(STC) in rats.
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[Preliminary assessment of the potential of biochar technology in mitigating the greenhouse effect in China].
Huan Jing Ke Xue
PUBLISHED: 08-17-2013
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The production of biochar by pyrolysis and its application to soil can sequester the CO2 which was absorbed by plants from atmosphere into soil, in addition it can also bring multiple benefits for agriculture production. On the basis of the available potential survey of the biomass residues from agriculture and forestry section, life cycle assessment was employed to quantify the potential of biochar technology in mitigation of greenhouse gases in our country. The results showed: In China, the amount of available biomass resource was 6.04 x 10(8) t every year and its net greenhouse effect potential was 5.32 x 10(8) t CO(2e) (CO(2e): CO2 equivalent), which was equivalent to 0.88 t CO(2e) for every ton biomass. The greatest of contributor to the total potential was plant carbon sequestration in soil as the form of biochar which accounts for 73.94%, followed by production of renewable energy and its percentage was 23.85%. In summary, production of biochar from agriculture and forestry biomass residues had a significant potential for our country to struggle with the pressure of greenhouse gas emission.
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[Temporal-spatial distribution of algal cells during drought period in Daning River of Three Gorges].
Huan Jing Ke Xue
PUBLISHED: 08-17-2013
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In order to provide basic data for algal bloom warning system, the study on temporal-spatial distribution of algal cells was carried out in Daning River of Three Gorges form April to September, 2011. The results of temporal distribution were as follows: the dominant algal species were blue algal, green algal and diatom. During the test, the density proportion of blue algae increased continuously, the density proportion of diatom decreased, while the density proportion of green algae did not change significantly. The results of spatial distribution were as follows: algal density was extremely significantly correlated with water temperature and chlorophyll a (Chl a), the correlation coefficient were 0.97 and 0.95, respectively; algal density was significantly correlated with light intensity (LI), dissolved oxygen (DO), pH and dissoluble total phosphorus (DTP), the correlation coefficient were 0.87, 0.83, 082 and 0.82, respectively; the algal density in 0 m of Caziba was higher than those in other water depths, and in Baishuihe the highest algal density occurred at 2.0 m water depth in June and July, in Shuanglong most algal cells were found in 0 m and 2.0 m in July, August and September, in Dachang algal density in different water depth did not change significantly during the test; the proportion of different algal species in vertical direction was different in the test, probably because different algal species fitted different environments.
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Role of gas vesicles and intra-colony spaces during the process of algal bloom formation.
Water Environ. Res.
PUBLISHED: 07-10-2013
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Aggregation morphology, vertical distribution, and algal density were analyzed during the algal cell floating process in three environments. The role of gas vesicles and intra-colony spaces was distinguished by algal blooms treated with ultrasonic waves and high pressure. Results demonstrated that the two buoyancy providers jointly provide buoyancy for floating algal cells. The results were also confirmed by force analysis. In the simulation experiment, the buoyancy acting on algal cells was greater than its gravity at sample ports 2 and 3 of a columnar-cultivated cell vessel, and intra-colony spaces were not detected. In Taihu Lake, gas vesicle buoyancy was notably less than total algal cell gravity. Buoyancy provided by intra-colony spaces exceeded total algal cell gravity at the water surface, but not at other water depths. In the Daning River, total buoyancies provided by the two buoyancy providers were less than total algal cell gravity at different water depths.
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Hydrothermal synthesis and electrochemical properties of KMn8O16 nanorods for lithium-ion battery applications.
J Nanosci Nanotechnol
PUBLISHED: 06-15-2013
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KMn8O16 nanorods were prepared through a facile hydrothermal method by using KMnO4 and MnSO4 as reactants. The KMn8O16 samples synthesized at different temperatures (100-160 degrees C) were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and its electrochemical properties were tested by galvanostatic charge/discharge system. The effect of reaction temperature on the morphology and electrochemical properties was investigated. As electrode materials for the lithium ion battery cycled between 1.5 and 4.2 V, the KMn8O16 nanorods synthesized at 160 degrees C show the highest reversible discharge capacity (160.1 mA h/g even after 50 cycles at current density of 50 mA/g) and the best cycling stability. These results indicate that the KMn8O16 nanorods could be a promising cathode material for lithium ion batteries.
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Inhibition of hepatitis B virus production in vitro by proteasome inhibitor MG132.
Hepatogastroenterology
PUBLISHED: 06-05-2013
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To investigate the suppressive effects of proteasome inhibitor MG132 on hepatitis B virus production.
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Orthogonal Design Study on Factors Affecting the Determination of Common Odors in Water Samples by Headspace Solid-Phase Microextraction Coupled to GC/MS.
J Anal Methods Chem
PUBLISHED: 05-30-2013
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Geosmin and 2-MIB are responsible for the majority of earthy and musty events related to the drinking water. These two odorants have extremely low odor threshold concentrations at ng?L(-1) level in the water, so a simple and sensitive method for the analysis of such trace levels was developed by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry. In this study, the orthogonal experiment design L32 (4(9)) was applied to arrange and optimize experimental conditions. The optimum was the following: temperatures of extraction and desorption, 65°C and 260°C, respectively; times of extraction and desorption, 30?min and 5?min, respectively; ionic strength, 25% (w/v); rotate-speed, 600?rpm; solution pH, 5.0. Under the optimized conditions, limits of detection (S/N = 3) were 0.04 and 0.13?ng?L(-1) for geosmin and 2-MIB, respectively. Calculated calibration curves gave high levels of linearity with a correlation coefficient value of 0.9999 for them. Finally, the proposed method was applied to water samples, which were previously analyzed and confirmed to be free of target analytes. Besides, the proposal method was applied to test environmental water samples. The RSDs were 2.75%~3.80% and 4.35%~7.6% for geosmin and 2-MIB, respectively, and the recoveries were 91%~107% and 91%~104% for geosmin and 2-MIB, respectively.
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Radioactive seed implantation combined with prosthesis denture in treatment of oral and maxillofacial malignancy.
Cell Biochem. Biophys.
PUBLISHED: 05-28-2013
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We sought to evaluate the effect of (125)I radioactive seed implantation combined with prosthesis denture on the treatment of oral and maxillofacial malignancy. For this purpose, 10 patients with glandule palatine malignancy were selected and subjected to the treatment plan of radioactive seed implantation during CT examination. All patients were treated as follow. The tumor tissues were extracted first. After 2 weeks, radioactive seeds were implanted in the palatine tissue and the prosthesis denture was made and worn for the tissue defect. Several radioactive seeds were still embedded in the tissue surface of the prosthesis at the same time; 24-36 seeds (average: 28) were used for each patient. All patients were followed up for 3-16 months and the results were evaluated. We found no tumor recurrence or metastasis around the target area in all patients. Significant improvement was shown in terms of speech, mastication, and facial appearance in all cases. Therefore, we concluded that in patients with glandule palatine malignancy, tumorectomy followed by radioactive seed implantation and prosthesis denture are effective for preventing the recurrence and metastasis of malignancy and improving the quality of life.
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"Magic" vicinal zinc oxide surfaces.
Phys. Rev. Lett.
PUBLISHED: 05-02-2013
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The structure of (0001) oriented ZnO single crystal surfaces is investigated by scanning tunneling microscopy. Depending on the preparation conditions, faceting of the crystals into large areas of {101¯4} surface orientation occurs. This restructuring of the surface is shown to be a consequence of dipole compensation and charge neutralization. A new stabilization mechanism of polar oxide surfaces is found which is based on the formation of vicinal surfaces with special electronic and structural properties.
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Evolutionary relationships of ATP-Binding Cassette (ABC) uptake porters.
BMC Microbiol.
PUBLISHED: 04-19-2013
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The ATP-Binding Cassette (ABC) functional superfamily includes integral transmembrane exporters that have evolved three times independently, forming three families termed ABC1, ABC2 and ABC3, upon which monophyletic ATPases have been superimposed for energy-coupling purposes [e.g., J Membr Biol 231(1):1-10, 2009]. The goal of the work reported in this communication was to understand how the integral membrane constituents of ABC uptake transporters with different numbers of predicted or established transmembrane segments (TMSs) evolved. In a few cases, high resolution 3-dimensional structures were available, and in these cases, their structures plus primary sequence analyses allowed us to predict evolutionary pathways of origin.
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[Identification of geographical origins of rice with pattern recognition technique by near infrared spectroscopy].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 04-17-2013
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A rapid method was developed for discrimination of the geographical origins of rice with pattern recognition technique by near infrared spectrocopy (NIRS). A total of 119 geography signs product Xiangshui rice samples and 90 rice (Non-Xiangshui rice) samples produced from other places were analyzed by NIRS. After first derivative and smooth processing, principal component analysis (PCA) was used to reduce the dimensionality of the spectral data. Through the loading graph of the first three principal components, characteristic wave band (7 700-6 700, 5 700-4 300 cm(-1)) with max-relativity was determined. In whole wave, using agglomerative hierarchical cluster analysis and Fishers linear discriminant, the discrimination of Xiangshui rice and Non-Xiangshui rice was all 100%. The correct rate of specific geographical origins of Non-Xiangshui rice was 91.9% by cluster analysis and 96.7% by discriminant analysis. For analysis in the characteristic wave bands, the correct rate of discriminant by cluster analysis was higher than the analysis result through the range of the whole band. Therefore, characteristic wave band has strong representativeness. The results indicate that it is feasible to discriminate the geographical origins of rice with pattern recognition technique by NIRS, and selecting characteristic wave band is one of the validated methods to improve the precision of the discrimination mode.
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Isoliquiritigenin induces growth inhibition and apoptosis through downregulating arachidonic acid metabolic network and the deactivation of PI3K/Akt in human breast cancer.
Toxicol. Appl. Pharmacol.
PUBLISHED: 04-15-2013
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Arachidonic acid (AA)-derived eicosanoids and its downstream pathways have been demonstrated to play crucial roles in growth control of breast cancer. Here, we demonstrate that isoliquiritigenin, a flavonoid phytoestrogen from licorice, induces growth inhibition and apoptosis through downregulating multiple key enzymes in AA metabolic network and the deactivation of PI3K/Akt in human breast cancer. Isoliquiritigenin diminished cell viability, 5-bromo-2-deoxyuridine (BrdU) incorporation, and clonogenic ability in both MCF-7 and MDA-MB-231cells, and induced apoptosis as evidenced by an analysis of cytoplasmic histone-associated DNA fragmentation, flow cytometry and hoechst staining. Furthermore, isoliquiritigenin inhibited mRNA expression of multiple forms of AA-metabolizing enzymes, including phospholipase A2 (PLA2), cyclooxygenases (COX)-2 and cytochrome P450 (CYP) 4A, and decreased secretion of their products, including prostaglandin E2 (PGE2) and 20-hydroxyeicosatetraenoic acid (20-HETE), without affecting COX-1, 5-lipoxygenase (5-LOX), 5-lipoxygenase activating protein (FLAP), and leukotriene B4 (LTB4). In addition, it downregulated the levels of phospho-PI3K, phospho-PDK (Ser(241)), phospho-Akt (Thr(308)), phospho-Bad (Ser(136)), and Bcl-xL expression, thereby activating caspase cascades and eventually cleaving poly(ADP-ribose) polymerase (PARP). Conversely, the addition of exogenous eicosanoids, including PGE2, LTB4 and a 20-HETE analog (WIT003), and caspase inhibitors, or overexpression of constitutively active Akt reversed isoliquiritigenin-induced apoptosis. Notably, isoliquiritigenin induced growth inhibition and apoptosis of MDA-MB-231 human breast cancer xenografts in nude mice, together with decreased intratumoral levels of eicosanoids and phospho-Akt (Thr(308)). Collectively, these data suggest that isoliquiritigenin induces growth inhibition and apoptosis through downregulating AA metabolic network and the deactivation of PI3K/Akt in human breast cancer.
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Sorption of antibiotic sulfamethoxazole varies with biochars produced at different temperatures.
Environ. Pollut.
PUBLISHED: 04-03-2013
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Sorption of sulfonamides on biochars is poorly understood, thus sulfamethoxazole (SMX) sorption on biochars produced at 300-600 °C was determined as a function of pH and SMX concentration, as well as the inorganic fractions in the biochars. Neutral SMX molecules (SMX(0)) were dominant for sorption at pH 1.0-6.0. Above pH 7.0, although biochars surfaces were negatively-charged, anionic SMX species sorption increased with pH and is regulated via charge-assisted H-bonds. SMX(0) sorption at pH 5.0 was nonlinear and adsorption-dominant for all the biochars via hydrophobic interaction, ?-? electron donor-acceptor interaction and pore-filling. The removal of inorganic fraction reduced SMX sorption by low-temperature biochars (e.g., 300 °C), but enhanced the sorption by high-temperature biochars (e.g., 600 °C) due to the temperature-dependent inorganic fractions in the biochars. These observations are useful for producing designer biochars as engineered sorbents to reduce the bioavailability of antibiotics and/or predict the fate of sulfonamides in biochar-amended soils.
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Immune function assay (ImmuKnow) as a predictor of allograft rejection and infection in kidney transplantation.
Clin Transplant
PUBLISHED: 03-06-2013
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The Cylex ImmuKnow (IK) assay provides a rapid and quantitative assessment of T-cell-mediated immune function. Studies have shown correlations between ImmuKnow assay and adverse events, such as immunosuppression and low or high calcineurin inhibitor trough levels. We investigated the correlation between IK changes and rejection or infection in kidney transplant patients and studied the potential application of the IK assays in optimizing individual immunosuppressive therapy.
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Manipulation of subsurface donors in ZnO.
Phys. Rev. Lett.
PUBLISHED: 02-26-2013
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Single donors close to the ZnO(0001) surface are investigated with scanning tunneling microscopy. Their binding energies and depths are determined from spatially resolved spectra of the differential conductance. At elevated bias of the STM tip, vertical motion of the donors can be induced. The direction of the motion can be controlled by the bias polarity.
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Molecular characterization of Japanese encephalitis virus strains prevalent in Chinese swine herds.
J. Vet. Sci.
PUBLISHED: 02-05-2013
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Japanese encephalitis virus (JEV) is the leading cause of viral encephalitis in Asia and domestic pigs serve as the amplifying hosts. In the present study, the full genomic sequences of two JEV strains (HEN0701 and SH0601) isolated from pigs in China were determined and compared with other 12 JEV strains deposited in GenBank. These two strains had an 88.8% nucleotide sequence similarity and 97.9% deduced amino acid sequence homology. HEN0701 had high nucleotide sequence and high amino acid sequence identity with genotype I (GI) strains, while SH0601 had high nucleotide sequence and high amino acid sequence identity with GIII strains at both the gene and full genome levels. Further phylogenetic analysis showed that HEN0701 belonged to the JEV GI group and SH0601 was classified as a GIII strain. Analysis of codon usage showed there were a few differences between the GI and GIII strains in nucleotide composition and codon usage for the open reading frames.
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CpGIMethPred: computational model for predicting methylation status of CpG islands in human genome.
BMC Med Genomics
PUBLISHED: 01-23-2013
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DNA methylation is an inheritable chemical modification of cytosine, and represents one of the most important epigenetic events. Computational prediction of the DNA methylation status can be employed to speed up the genome-wide methylation profiling, and to identify the key features that are correlated with various methylation patterns. Here, we develop CpGIMethPred, the support vector machine-based models to predict the methylation status of the CpG islands in the human genome under normal conditions. The features for prediction include those that have been previously demonstrated effective (CpG island specific attributes, DNA sequence composition patterns, DNA structure patterns, distribution patterns of conserved transcription factor binding sites and conserved elements, and histone methylation status) as well as those that have not been extensively explored but are likely to contribute additional information from a biological point of view (nucleosome positioning propensities, gene functions, and histone acetylation status). Statistical tests are performed to identify the features that are significantly correlated with the methylation status of the CpG islands, and principal component analysis is then performed to decorrelate the selected features. Data from the Human Epigenome Project (HEP) are used to train, validate and test the predictive models. Specifically, the models are trained and validated by using the DNA methylation data obtained in the CD4 lymphocytes, and are then tested for generalizability using the DNA methylation data obtained in the other 11 normal tissues and cell types. Our experiments have shown that (1) an eight-dimensional feature space that is selected via the principal component analysis and that combines all categories of information is effective for predicting the CpG island methylation status, (2) by incorporating the information regarding the nucleosome positioning, gene functions, and histone acetylation, the models can achieve higher specificity and accuracy than the existing models while maintaining a comparable sensitivity measure, (3) the histone modification (methylation and acetylation) information contributes significantly to the prediction, without which the performance of the models deteriorate, and, (4) the predictive models generalize well to different tissues and cell types. The developed program CpGIMethPred is freely available at http://users.ece.gatech.edu/~hzheng7/CGIMetPred.zip.
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The effect of crosslinking agents on the transfection efficiency, cellular and intracellular processing of DNA/polymer nanocomplexes.
Biomaterials
PUBLISHED: 01-19-2013
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Cellular and intracellular processing of DNA/polymer nanocomplexes was optimized by tailoring the composition of crosslinking agents for improving in vitro and in vivo transfection efficiency. Nanocomplexes composed of trimethyl chitosan-arginine conjugate (TMC-Arg), plasmid DNA (pDNA), and different proportions of sodium tripolyphosphate (TPP) and poly(?-glutamic acid) (?-PGA) were prepared. All TMC-Arg nanocomplexes (TANC) possessed similar particle sizes and preferable protection of pDNA against degradation. The Zeta potentials of TANC decreased with increasing amount of TPP, which were positively correlated to their cellular uptake levels. The composition of crosslinking agents affected their internalization mechanisms, wherein the addition of ?-PGA changed from clathrin-mediated endocytosis to caveolae-mediated one. The increment of TPP amount in TANC was responsible for their reduced binding affinity to pDNA and rapid pDNA release, which was related to their subcellular distribution and in vitro and in vivo transfection patterns. More compact TANC were associated with a delayed protein expression while easily dissociated ones gave a faster onset of action and higher short term gene transfer. However, TANC that dissociated too readily had the inability of gene transfection owing to pDNA degradation in the endolysosomes. Therefore, tailoring the composition of crosslinking agents in nanocomplexes may provide a feasible tool for improving transfection efficiency.
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Development and verification of a mouse model for Roux-en-Y gastric bypass surgery with a small gastric pouch.
PLoS ONE
PUBLISHED: 01-11-2013
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Existing mouse models of Roux-en-Y gastric bypass (RYGB) surgery are not comparable to human RYGB in gastric pouch volume for a large or absent gastric volume. The aim of this study was to develop and characterize a mouse RYGB model that closely replicates gastric pouch size of human RYGB surgery of about 5% of total gastric volume. We established this model in diet-induced obese (DIO) mice of C57BL/6J. This surgery resulted in a sustained 30% weight loss, entirely accounted for by decreased fat mass but not lean mass, compared to sham-operated mice on the high fat diet. Compared to sham-operated mice, energy expenditure corrected for total body weight was significantly increased by about 25%, and substrate utilization was shifted toward higher carbohydrate utilization at 8 weeks after RYGB when body weight had stabilized at the lower level. The energy expenditure persisted and carbohydrate utilization was even more pronounced when the mice were fed chow diet. Although significantly increased during daytime, overall locomotor activity was not significantly different. In response to cold exposure, RYGB mice exhibited an improved capacity to maintain the body temperature. In insulin tolerance test, exogenous insulin-induced suppression of plasma glucose levels was significantly greater in RYGB mice at 4 weeks after surgery. Paradoxically, food intake measured at 5 weeks after surgery was significantly increased, possibly in compensation for increased fecal energy loss and energy expenditure. In conclusion, this new model is a viable alternative to existing murine RYGB models and the model matches human RYGB surgery in anatomy. This model will be useful for studying molecular mechanisms involved in the beneficial effects of RYGB on body weight and glucose homeostasis.
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Advances in the Techniques for the Prediction of microRNA Targets.
Int J Mol Sci
PUBLISHED: 01-07-2013
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MicroRNAs (miRNAs) are small, non-coding, endogenous RNA molecules that play important roles in a variety of normal and diseased biological processes by post-transcriptionally regulating the expression of target genes. They can bind to target messenger RNA (mRNA) transcripts of protein-coding genes and negatively control their translation or cause mRNA degradation. miRNAs have been found to actively regulate a variety of cellular processes, including cell proliferation, death, and metabolism. Therefore, their study is crucial for the better understanding of cellular functions in eukaryotes. To better understand the mechanisms of miRNA: mRNA interaction and their cellular functions, it is important to identify the miRNA targets accurately. In this paper, we provide a brief review for the advances in the animal miRNA target prediction methods and available resources to facilitate further study of miRNAs and their functions.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.