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Find video protocols related to scientific articles indexed in Pubmed.
Asymmetric Hetero-Diels-Alder Reaction of Diazenes Catalyzed by Chiral Silver Phosphate: Water Participates in the Catalysis and Stereocontrol.
Org. Lett.
PUBLISHED: 11-20-2014
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The chiral silver phosphate was confirmed to efficiently catalyze a highly regio- and enantioselective hetero-Diels-Alder reaction of diazenes to furnish piperazine derivatives in high yields and excellent ee values. DFT calculations revealed that the water molecule participates in the catalysis by coordination to silver phosphate and also found that the hydroxy group of 1-hydroxy-2,3-hexadiene not only formed a hydrogen bond with the oxygen of phosphate but also coordinated to the Ag(I) to simultaneously stabilize the transition states and control the regioselectivity.
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Supramolecular polymeric vesicles formed by p-sulfonatocalix[4]arene and chitosan with multistimuli responses.
Soft Matter
PUBLISHED: 11-20-2014
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Supramolecular polymeric vesicles are constructed by the complexation of p-sulfonatocalix[4]arene and chitosan, where the multivalent electrostatic interactions between the anionic sulfonate tetramer and cationic polyammoniums served as the dominant driving force. The supra-amphiphilic assemblies are disassembled upon exposure to a pH stimulus since the partial deprotonation of chitosan accompanied by a pH increase. Adding a competitive guest can also disrupt the assembly, representing the host-guest inclusion response. Interestingly, an abnormal temperature-response is observed, possibly as a result of the temperature-directed fusion process.
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HIV risk among female sex workers with different patterns of drug use behaviors in Southwest China: a cross-sectional study.
AIDS Care
PUBLISHED: 11-20-2014
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Although many researchers found that drug use behaviors significantly increased HIV risk, few of them investigated the association between HIV risk and different drug use behaviors among female sex workers (FSWs) in China. The current study examines demographic and behavioral risk factors as well as the infections of HIV, syphilis, and among a subgroup of FSWs who are injection drug users (IDU) or noninjection drug users (NIDU) in comparison to Hepatitis C Virus (HCV) nondrug users (non-DU). We conducted secondary analysis of the 2010 National Sentinel Surveillance (NSS) data from Guangxi China. A self-administered, standard behavioral surveillance survey was completed by a total of 12,622 FSWs recruited from Guangxi, China. The Guangxi 2010 NSS sample included 2.6% NIDU and 0.5% IDU. Compared to non-DU, IDU were more likely to report no condom use in the last sex act (aOR = 3.25, 95%CI = 1.65, 6.40), inconsistent condom use in the past month (aOR = 4.88, 95%CI = 2.66, 8.96), having an HIV testing (aOR = 2.48, 95%CI = 1.34, 4.58), infections of HIV (aOR = 42.60, 95%CI = 9.45, 192.06), syphilis (aOR = 4.13, 95%CI = 1.86, 9.16), and HCV (aOR = 74.54, 95%CI = 30.26, 183.61). NIDU had 2.89 times higher than non-DU to report a history of sexually transmitted disease and 26% less likely to report inconsistent condom use in the past month (p < 0.05). We called for tailored, accessible, and nonjudgmental drug treatments coupled with effective sexual risk reduction interventions to help FSWs with various drug use problems to reduce their vulnerability and susceptibility of HIV risk in China as well as other cultural settings.
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Rapid synthesis of isoquinolinones by intramolecular coupling of amides and ketones.
Org. Biomol. Chem.
PUBLISHED: 11-20-2014
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Amides and ketones were intramolecularly coupled in the presence of KOt-Bu/DMF. The reaction provided good yields of a variety of isoquinolinones. A reaction mechanism of radical addition and subsequent E2-elimination is proposed.
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Salvia miltiorrhiza Injection on Pulmonary Heart Disease: A Systematic Review and Meta-Analysis.
Am. J. Chin. Med.
PUBLISHED: 11-15-2014
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Cor pulmonale (pulmonary heart disease) is a chronic progressive complicated disease for which treatment needs to be sustained all the time, creating a great financial burden on individuals and society. In order to improve the life quality of cor pulmonale patients and decrease the dosage and quantity of the routine treatment, in China, TCM is often administered to patients with cor pulmonale. The results of many clinical trials have indicated that Salvia miltiorrhiza and complex Salvia miltiorrhiza injection may be an alternative medicine for cor pulmonale. With the purpose to prove whether Salvia miltiorrhiza and complex Salvia miltiorrhiza benefit the cor pulmonale patients, respectively, we carried out a systematic review to evaluate the efficacy and safety of Salvia miltiorrhiza and complex Salvia miltiorrhiza injection in cor pulmonale patients. Overall, 2,715 patients were identified from 35 randomized controlled trials. The meta-analysis used I(2) test for heterogeneity and chose random or fixed model according to heterogeneity of included studies. Clinical outcomes were evaluated by total effectiveness rate, partial pressure of oxygen ( PaO 2) and carbon dioxide ( PaCO 2), hemorheology, mPAP and adverse effects. Compared with routine medicine treatment alone, routine medicine treatment plus Salvia miltiorrhiza or complex Salvia miltiorrhiza injection showed better outcomes: A significantly higher clinical effectiveness rate ratio (p < 0.001), increase in PaO 2 (p < 0.001) and decrease in PaCO 2 (p < 0.001), improvement in hemorheology (p < 0.001), and alleviation in mPAP (p < 0.05). There is no obvious adverse effect reported. In summary, there are some evidences suggesting that Salvia miltiorrhiza or complex Salvia miltiorrhiza injection are active in cor pulmonale, however, the results were limited by the methodological flaws of the included studies. Long-term and high quality clinical trials are needed to provide more conclusive evidence for the future use of Salvia miltiorrhiza injection.
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Sulfur Incorporation: Copper-Catalyzed Cascade Cyclization of 1,7-Enynes with Metal Sulfides toward Thieno[3,4-c]quinolin-4(5H)-ones.
Org. Lett.
PUBLISHED: 11-11-2014
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A novel copper-catalyzed cascade cyclization of 1,7-enynes with metal sulfides is described. This sulfur-incorporation method provides straightforward access toward the important thiophene-fused quinolin-4(5H)-one scaffold through cyclization and double C-S bond formation cascade, and the chemoselectivity of this 1,7-enyne cyclization toward 1,3,3a,9b-tetrahydrothieno[3,4-c]quinolin-4(5H)-ones and 3,3a-dihydrothieno[3,4-c]quinolin-4(5H)-ones can be controlled by varying the sulfur resources.
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Cognitive motor interference for preventing falls in older adults: a systematic review and meta-analysis of randomised controlled trials.
Age Ageing
PUBLISHED: 11-08-2014
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we conducted a systematic review to determine the effect of cognitive motor interference (CMI) for the prevention of falls in older adults.
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[Expression of survivin in ameloblastoma and its clinical significance].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 10-24-2014
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To study the expression of survivin in ameloblastoma and its clinical significance.
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Multiple advanced surgical techniques to treat acquired seminal duct obstruction.
Asian J. Androl.
PUBLISHED: 10-23-2014
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The aim of this study was to evaluate the outcomes of multiple advanced surgical treatments (i.e. microsurgery, laparoscopic surgery and endoscopic surgery) for acquired obstructive azoospermia. We analyzed the surgical outcomes of 51 patients with suspected acquired obstructive azoospermia consecutively who enrolled at our center between January 2009 and May 2013. Modified vasoepididymostomy, laparoscopically assisted vasovasostomy and transurethral incision of the ejaculatory duct with holmium laser were chosen and performed based on the different obstruction sites. The mean postoperative follow-up time was 22 months (range: 9 months to 52 months). Semen analyses were initiated at four postoperative weeks, followed by trimonthly (months 3, 6, 9 and 12) semen analyses, until no sperm was found at 12 months or until pregnancy was achieved. Patency was defined as >10,000 sperm ml-1 of semen. The obstruction sites, postoperative patency and natural pregnancy rate were recorded. Of 51 patients, 47 underwent bilateral or unilateral surgical reconstruction; the other four patients were unable to be treated with surgical reconstruction because of pelvic vas or intratesticular tubules obstruction. The reconstruction rate was 92.2% (47/51), and the patency rate and natural pregnancy rate were 89.4% (42/47) and 38.1% (16/42), respectively. No severe complications were observed. Using multiple advanced surgical techniques, more extensive range of seminal duct obstruction was accessible and correctable; thus, a favorable patency and pregnancy rate can be achieved.
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SHP2 Positively Regulates TGF?1-induced Epithelial-mesenchymal Transition Modulated by Its Novel Interacting Protein Hook1.
J. Biol. Chem.
PUBLISHED: 10-22-2014
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The epithelial-mesenchymal transition (EMT) is an essential process for embryogenesis. It also plays a critical role in the initiation of tumor metastasis. Src homology 2 (SH2)-domain containing protein tyrosine phosphatase-2 (SHP2) is a ubiquitously-expressed protein tyrosine phosphatase and is mutated in many tumors. However, its functional role in tumor metastasis remains largely unknown. We found that TGF?1-induced EMT in lung epithelial A549 cells was partially blocked when SHP2 was decreased by transfected siRNA. The constitutively active form (Glu76Val) promoted EMT while the phosphatase-dead mutation (Cys459Ser) and the SHP2 inhibitor PHPS1 blocked EMT, which further demonstrated that the phosphatase activity of SHP2 was required for promoting TGF?1-induced EMT. Using the protein tyrosine phosphatase domain of SHP2 as bait, we identified a novel SHP2-interacting protein Hook1. Hook1 was down-regulated during EMT in A549 cells. Overexpression of Hook1 inhibited EMT while knockdown of Hook1 promoted EMT. Moreover, both the protein tyrosine phosphatase domain and N-terminal SH2 domain of SHP2 directly interacted with Hook1. Down-regulation of Hook1 increased SHP2 activity. These results suggested that Hook1 was an endogenous negative regulator of SHP2 phosphatase activity. Our data showed that the protein tyrosine phosphatase SHP2 was involved in the process of EMT and Hook1 repressed EMT by regulating the activation of SHP2. SHP2-Hook1 complex may play important roles in tumor metastases by regulating EMT in cancer cells.
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Fabrication of 3D photonic crystals from chitosan that are responsive to organic solvents.
Biomacromolecules
PUBLISHED: 10-18-2014
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Inspired by photonic nanostructures in nature, such as the hair-like chaetae on the body of sea mice, inverse opal photonic crystals films were fabricated with chitosan, a kind of biomacromolecule found in nature. First monodispersed polystyrene (PS) colloidal crystal templates with different particle sizes were prepared. The inverse opal films (IOFs) were fabricated through in situ cross-linking of the PS templates. The IOFs contain periodically ordered interconnecting pores that endow the films with photonic band gaps and structural colors which are visible to bare eye. The IOFs exhibit rapid reversible changes in their structural colors and reflectance peaks in response to alcohols and phenols. Possible mechanisms for the shifts in the IOF's reflectance peaks are proposed. The changes in the IOFs in response to alcohols and phenols provide a potential way to visually detect these organic solvents.
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Tunable trapping and releasing light in graded graphene-silica metamaterial waveguide.
Opt Express
PUBLISHED: 10-17-2014
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We present a detailed study on trapping and releasing of light in a graded graphene-silica metamaterial waveguide. By applying proper gate voltages onto the graphene layers, the metamaterial with graded-permittivity has the ability to trap the light due to the vanishing of normalized optical power flow between forward and backward modes. Based on the effective medium theory, the distributions of modes and the transmission characteristics of normalized power flows are investigated. Theoretical investigation shows that the waveguide has the ability to turn on or off the mid-infrared light from 5400 nm to 5800 nm. Moreover, adjusting the voltages on graphene layers can alter the bandwidth of trapped light. The graded metamaterial waveguide can be the candidate for multi-wavelength absorber based on the light trapping effect.
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Copper-catalyzed cascade cyclization of 1,7-enynes with aromatic sulfonyl chlorides toward selective assembly of benzo[j]phenanthridin-6(5H)-ones.
Chem. Commun. (Camb.)
PUBLISHED: 10-11-2014
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A step-economical method for the cascade cyclization of 1,7-enynes with aromatic sulfonyl chlorides by using a low-cost and more abundant Cu catalyst is presented. This method allows access to benzo[j]phenanthridin-6(5H)-ones and represents a new Cu-catalyzed cascade cyclization of 1,n-enynes.
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PARP-14 combines with tristetraprolin in the selective post-transcriptional control of macrophage tissue factor expression.
Blood
PUBLISHED: 10-09-2014
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Tissue factor (TF, CD142) is a 47 kDa transmembrane cell surface glycoprotein which triggers the extrinsic coagulation cascade and links thrombosis with inflammation. Although macrophage TF expression is known to be regulated at the RNA level, very little is known about the mechanisms involved. Poly(ADP-ribose)-polymerase (PARP)-14 belongs to a family of intracellular proteins that generate ADP-ribose post-translational adducts. Functional screening of PARP-14 deficient macrophages mice revealed that PARP-14 deficiency leads to increased tissue factor (TF) expression and functional activity in macrophages following challenge with bacterial lipopolysaccharide. This was related to an increase in TF mRNA stability. Ribonucleoprotein complex immunoprecipitation and biotinylated RNA pull-down assays demonstrated that PARP-14 forms a complex with the mRNA-destabilizing protein tristetraprolin (TTP) and a conserved AU-rich element in the TF mRNA 3' untranslated region. TF mRNA regulation by PARP-14 was selective, as TNF? mRNA, which is also regulated by TTP, was not altered in PARP-14 deficient macrophages. Consistent with the in vitro data, TF expression and TF activity, but not TNF? expression, were increased in Parp14(-/-) mice in vivo. Our study provides a novel mechanism for the post-transcriptional regulation of TF expression, indicating that this is selectively regulated by PARP-14.
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Flush-mounted probe diagnostics for argon glow discharge plasma.
Rev Sci Instrum
PUBLISHED: 10-03-2014
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A comparison is made between plasma parameters measured by a flush-mounted probe (FP) and a cylindrical probe (CP) in argon glow discharge plasma. Parameters compared include the space potential, the plasma density, and the effective electron temperature. It is found that the ion density determined by the FP agrees well with the electron density determined by the CP in the quasi-neutral plasma to better than 10%. Moreover, the space potential and effective electron temperature calculated from electron energy distribution function measured by the FP is consistent with that measured by the CP over the operated discharge current and pressure ranges. These results present the FP can be used as a reliable diagnostic tool in the stable laboratory plasma and also be anticipated to be applied in other complicated plasmas, such as tokamaks, the region of boundary-layer, and so on.
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Platelet function monitoring guided antiplatelet therapy in patients receiving high-risk coronary interventions.
Chin. Med. J.
PUBLISHED: 10-02-2014
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Large-scale clinical trials have shown that routine monitoring of the platelet function in patients after percutanous coronary intervention (PCI) is not necessary. However, it is still unclear whether patients received high-risk PCI would benefit from a therapy which is guided by a selective platelet function monitoring. This explanatory study sought to assess the benefit of a therapy guided by platelet function monitoring for these patients.
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Facile fabrication of porous CL-20 for low sensitivity high explosives.
Phys Chem Chem Phys
PUBLISHED: 10-01-2014
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A facile solvent/non-solvent co-crystallization technology is applied to fabricate porous CL-20, which exhibits interesting morphologies and low sensitivity with ?-cyclodextrin as a crystal modifier.
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Rice SPX1 and SPX2 inhibit phosphate starvation responses through interacting with PHR2 in a phosphate-dependent manner.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-30-2014
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In plants, sensing the levels of external and internal nutrients is essential for reprogramming the transcriptome and adapting to the fluctuating environment. Phosphate (Pi) is a key plant nutrient, and a large proportion of Pi starvation-responsive genes are under the control of PHOSPHATE STARVATION RESPONSE REGULATOR 1 (PHR1) in Arabidopsis (AtPHR1) and its homologs, such as Oryza sativa (Os)PHR2 in rice. AtPHR1 and OsPHR2 expression is not very responsive to Pi starvation, raising the question as to how plants sense changes in cellular Pi levels to activate the central regulator. SPX [named after SYG1 (suppressor of yeast gpa1), Pho81 (CDK inhibitor in yeast PHO pathway), and XPR1 (xenotropic and polytropic retrovirus receptor)] proteins that harbor only the SPX domain are reported to be involved in the negative regulation of Pi starvation responses. Here, we show that the nuclear localized SPX proteins SPX1 and SPX2 are Pi-dependent inhibitors of the activity of OsPHR2 in rice. Indeed, SPX1 and SPX2 proteins interact with PHR2 through their SPX domain, inhibiting its binding to P1BS (the PHR1-binding sequence: GNATATNC). In vivo data, as well as results from in vitro experiments using purified SPX1, SPX2, and OsPHR2 proteins, showed that SPX1 and SPX2 inhibition of OsPHR2 activity is Pi-dependent. These data provide evidence to support the involvement of SPX1 and SPX2 in the Pi-sensing mechanism in plants.
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Influence of Chm-I knockout on ectopic cartilage regeneration and homeostasis maintenance.
Tissue Eng Part A
PUBLISHED: 09-25-2014
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Ectopic ossification of mesenchymal stem cell (MSC) regenerated cartilage have greatly restricted its application in repairing subcutaneous cartilage defects (such as nasal or auricular). Different from MSCs, chondrocytes can maintain stable chondrogenic phenotype in ectopic microenvironment, which was speculated to be related with the existence of anti-angiogenic factors such as Chondromodulin-I (Chm-I). Therefore, the purpose of this study was to illustrate whether Chm-I was indispensable for stable ectopic chondrogenesis by chondrocyte, which may help to solve the problem of MSC ectopic ossification in future. The current study demonstrated that Chm-I knockout did not obviously influence articular cartilage development in situ. However, native articular cartilage from Chm-I knockout (Chm-I-/-, KO) but not wild type (WT) mice showed obvious ossification after subcutaneously implanted into nude mice for 16 d. Interestingly, cell morphology, cartilage specific matrix expression, and pellet culture demonstrated that Chm-I knockout had no obvious influence on phenotype, function, and chondrogenic ability of chondrocytes in vitro, except that cells in WT group proliferated a little faster than those in KO group. Nevertheless, Chm-I knockout directly interfered with in vivo ectopic cartilage regeneration when chondrocytes were subcutaneously injected into nude mice with matrigel. Moreover, Chm-I knockout obviously compromised ectopic stability of in vitro regenerated cartilage after subcutaneous implantation. These findings indicated that Chm-I was an indispensable factor for ectopic cartilage regeneration and the maintenance of cartilage homeostasis, which may provide a clue for solving the stability problem of MSC regenerated cartilage in ectopic niche. In addition, this study also provides a novel model based on tissue engineering strategy to properly evaluate the function of other targeted genes.
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An acid-free rechargeable battery based on PbSO4 and spinel LiMn2O4.
Chem. Commun. (Camb.)
PUBLISHED: 09-25-2014
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An acid-free lead rechargeable battery system comprising PbSO4 as the negative electrode, LiMn2O4 as the positive electrode and a neutral Li2SO4 aqueous solution as electrolyte is reported and its electrochemical performance is very good. It shows great promise to reduce the global use of lead by 50% since it is also low cost.
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Creative educational use of virtual reality: working with Second Life.
IEEE Comput Graph Appl
PUBLISHED: 09-24-2014
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Hong Kong Polytechnic University educators used the Second Life virtual world to help students learn the relationships between key concepts in designing clothing for functional comfort.
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[Experimental study on hepatitis B-virus X gene expression in adenoid cystic carcinoma].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 09-23-2014
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To explore the expression of hepatitis B-virus X gene (HBX) in adenoid cystic carcinoma (ACC) and determine its clinical significance.
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[Comparison of 3-hour and 30-minute infusion regimens for meropenem in patients with hospital acquired pneumonia in intensive care unit: a randomized controlled clinical trial].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 09-19-2014
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To Compare the clinical efficacy and safety of meropenem with a 3-hour extended infusion or conventional 30-minute infusion regimen in treatment of hospital acquired pneumonia (HAP) in intensive care unit (ICU) patients.
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[Laws of acupoint selection of prescriptions for treatment of cervicogenic headache by acupuncture: a modern literature research].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 09-17-2014
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To summarize laws of acupoint selection of prescriptions for treatment of cervicogenic headache by acupuncture in modern literature.
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A small-sized graphene oxide supramolecular assembly for targeted delivery of camptothecin.
Chem. Commun. (Camb.)
PUBLISHED: 09-16-2014
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A small-sized graphene oxide supramolecular assembly was obtained by the inclusion complexation of hyaluronated adamantane with ?-cyclodextrin and the ?-stacking of graphene oxide with camptothecin, exhibiting an excellent stability in the serum environment and a higher inhibition effect toward malignant cells than a free drug.
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[Research on expression and function of phosphorylated DARPP-32 on pentylenetetrazol-induced epilepsy model of rat].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 09-16-2014
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The present study is to explore the change process and distribution of phosphorylated DARPP-32 (p-DARPP-32) in rat brain including cortex, hippocampus and striatum and to further deduce whether p-DARPP-32 was possibly involved in epilepsy induced by repetitive low doses of pentylenetetrazol (PTZ). PTZ-induced epilepsy model in rat was established with 30 male SD rats randomly divided into 6 groups, control group and five trial groups [PTZ 1 h, PTZ 6 h, PTZ 24 h, PTZ 48 h and PTZ 72 h respectively, after onset of status epilepticus (SE)]. Immunohistochemistry and immunofluorescence double-labeling were used to detect the temporal time change and distribution of p-DARPP-32 expression and to analyze the coexpression of DARPP-32 and p-DARPP-32 in rat brain after the onset of PTZ-induced generalized SE. The results showed that there was a temporal time change of p-DARPP-32 expression in rat brain after the onset of SE. The number of p-DARPP-32-positive cells increased significantly and reached the peaks at the ends of 1 hour and 6 hours after the onset of SE, but decreased at the end of 24 hours. The moderate to strong p-DARPP-32-immunopositive neurons were observed in cortex, hippocampus and striatum, and located in cell cytoplasm and cell nucleus. Further immunofluorescence double-labeling revealed that denser colocalization of p-DARPP-32 and DARPP-32 in the neurons existed in the area mentioned above. Therefore, PTZ-induced SE may cause phosphorylation of DARPP-32 in rat brain. The temporal time change and distribution of p-DARPP-32 suggest that phosphorylation of DARPP-32 may be involved in PTZ-induced epilepsy in rat brain including cortex, hippocampus and striatum, and p-DARPP-32 may play a central role in the onset of SE.
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De novo-designed enzymes as small-molecule-regulated fluorescence imaging tags and fluorescent reporters.
J. Am. Chem. Soc.
PUBLISHED: 09-11-2014
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Enzyme-based tags attached to a protein-of-interest (POI) that react with a small molecule, rendering the conjugate fluorescent, are very useful for studying the POI in living cells. These tags are typically based on endogenous enzymes, so protein engineering is required to ensure that the small-molecule probe does not react with the endogenous enzyme in the cell of interest. Here we demonstrate that de novo-designed enzymes can be used as tags to attach to POIs. The inherent bioorthogonality of the de novo-designed enzyme-small-molecule probe reaction circumvents the need for protein engineering, since these enzyme activities are not present in living organisms. Herein, we transform a family of de novo-designed retroaldolases into variable-molecular-weight tags exhibiting fluorescence imaging, reporter, and electrophoresis applications that are regulated by tailored, reactive small-molecule fluorophores.
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A Convenient Method for hTfR1 Inclusion Body Purification.
Prep. Biochem. Biotechnol.
PUBLISHED: 09-11-2014
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Human transferrin receptor, referred as hTfR1, is ubiquitously expressed at low levels in most normal human tissues, however, the expression level of hTfR1 in Blood brain barrier (BBB) and tumor tissues is relatively higher. hTfR1 is a type II homo dimeric transmembrane protein. The extracellular domain of hTfR1 consists of three domains: helical domain, apical and protease-like domain. In order to prepare hTfR1 antibody which can be utilized to deliver drugs across BBB through receptor mediated endocytosis, we began to express non-ligand binding domain of hTfR1 in E. coli BL21 Transetta (DE3). TfR1 gene was first obtained from HepG2 cells by RT-PCR and then inserted into pET 32a (c+) vector. The protein was expressed in the form of inclusion body with extreme high purity by the E. coli BL21 Transetta (DE3) and the purity was further improved by size exclusive chromatography. Western blot test indicated that the recombinant protein was TfR1 as expected. Above all, this report provided a convenient protocol that could be fulfilled in order to prepare hTfR1 inclusion body which failed to be purified by Ni(2+) affinity column.
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Two dimensional dipolar coupling in monolayers of silver and gold nanoparticles on a dielectric substrate.
Nanoscale
PUBLISHED: 09-09-2014
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The dimensionality of assembled nanoparticles plays an important role in their optical and magnetic properties, via dipolar effects and the interaction with their environment. In this work we develop a methodology for distinguishing between two (2D) and three (3D) dimensional collective interactions on the surface plasmon resonance of assembled metal nanoparticles. Towards that goal, we elaborate different sets of Au and Ag nanoparticles as suspensions, random 3D arrangements and well organized 2D arrays. Then we model their scattering cross-section using effective field methods in dimension n, including interparticle as well as particle-substrate dipolar interactions. For this modelling, two effective field medium approaches are employed, taking into account the filling factors of the assemblies. Our results are important for realizing photonic amplifier devices.
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Mechanism of pretreatment using magnetic poly(glycidyl methacrylate) resin in an ultrafiltration membrane system used in algae-rich water treatment.
Environ Technol
PUBLISHED: 09-03-2014
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Ultrafiltration (UF) membrane fouling brought by algae-rich water controlling has been the research focus in recent years. The pretreatment of magnetic poly(glycidyl methacrylate) (m-PGMA) for sedimental tank effluent was investigated as well as its performance in combined UF processes. The optimal dose of m-PGMA was found to be 5?mL/L, which can bring a significant improvement to the removal efficiency of natural organic matter. With regards to membrane fouling, the use of m-PGMA also resulted in lowered irreversible and reversible membrane resistances in comparison with results obtained when operating without m-PGMA. In addition, four classic filtration models were introduced to analyse the fouling mechanisms. The proportion of standard blocking of pores has been weakened in the mechanism of membrane fouling when the pretreatment of m-PGMA exists. A very loose cake layer and relieved pore blockage were observed by scanning electron microscopy during m-PGMA/UF process.
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Mir-155 promotes cervical cancer cell proliferation through suppression of its target gene LKB1.
Tumour Biol.
PUBLISHED: 08-26-2014
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MicroRNAs (miRNAs) are important regulators of many physiological and pathological processes, including cell proliferation, apoptosis, and cell cycle arrest. In this study, we aimed to investigate the biological role of miR-155 in cervical cancer and the underlying molecular mechanism involved in tumorigenesis. The expression of miR-155 in human cervical cancer tissues was detected by real-time PCR. MTT assay and BrdU incorporation assay were used to measure the proliferation of cervical cancer cells. Apoptosis cells and cell cycle distribution were analyzed by flow cytometry. We found that the expression of miR-155 was upregulated in cervical cancer tissues compared to the adjacent non-cancer tissues. Overexpression of miR-155 promoted the proliferation of Hela and SiHa cells. By contrast, downregulation of miR-155 inhibited the growth of cervical cancer cells. Flow cytometry analysis showed that low expression of miR-155 promoted apoptosis and induced cell cycle arrest in Hela and SiHa cells. Moreover, the mRNA and protein expression of LKB1 was significantly reduced in cervical cancer tissues. Luciferase reporter assay demonstrated that LKB1 was a target gene of miR-155, suggesting that miRNA-155 promoted the proliferation of cervical cancer cells by regulating LKB1 expression.
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An improved classical mapping method for homogeneous electron gases at finite temperature.
J Chem Phys
PUBLISHED: 08-20-2014
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We introduce a modified classical mapping method to predict the exchange-correlation free energy and the structure of homogeneous electron gases (HEG) at finite temperature. With the classical map temperature parameterized on the basis of the quantum Monte Carlo simulation data for the correlation energy and exact results at high and low temperature limits, the new theoretical procedure greatly improves the classical mapping method for correlating the energetic properties HEG over a broad range of thermodynamic conditions. Improvement can also be identified in predicting the long-range components of the spin-averaged pair correlation functions.
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Enhancement in bioavailability of ketorolac tromethamine via intranasal in situ hydrogel based on poloxamer 407 and carrageenan.
Int J Pharm
PUBLISHED: 08-17-2014
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The objective of this study was to construct a new in situ gel system based on the combination of poloxamer 407 and carrageenan (carrageenan-poloxamer 407 hydrogel, CPH) for intranasal delivery of ketorolac tromethamine. CPH showed potassium ion concentration - dependent erosion characteristics which ensured slow erosion in aqueous environment containing potassium ion at the physiological level. Loading with ketorolac tromethamine influenced erosion, drug release and thermosensitive properties of CPH. CPH containing 15% ketorolac tromethamine showed suitable gelation temperature (near 35°C) and in vitro sustained release profiles. Pharmacokinetic study of intranasal CPH containing 15% ketorolac tromethamine in rats demonstrated enhanced absolute bioavailability (68.8 ± 23.3%) and prolonged mean residence time (8.8 ± 3.5h) in comparison with the intranasal solution group (24.8 ± 13.8%, 3.9 ± 0.6h). Nasal ciliotoxicity evaluation on an in situ toad palate model preliminarily showed the safety of CPH for intranasal use. All results suggested the potential of CPH as a new sustained - release platform for the intranasal delivery of ketorolac tromethamine.
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Joint analysis of three genome-wide association studies of esophageal squamous cell carcinoma in Chinese populations.
Chen Wu, Zhaoming Wang, Xin Song, Xiao-Shan Feng, Christian C Abnet, Jie He, Nan Hu, Xian-Bo Zuo, Wen Tan, Qimin Zhan, Zhibin Hu, Zhonghu He, Weihua Jia, Yifeng Zhou, Kai Yu, Xiao-Ou Shu, Jian-Min Yuan, Wei Zheng, Xue-Ke Zhao, She-Gan Gao, Zhi-Qing Yuan, Fu-You Zhou, Zong-Min Fan, Ji-Li Cui, Hong-Li Lin, Xue-Na Han, Bei Li, Xi Chen, Sanford M Dawsey, Linda Liao, Maxwell P Lee, Ti Ding, You-Lin Qiao, Zhihua Liu, Yu Liu, Dianke Yu, Jiang Chang, Lixuan Wei, Yu-Tang Gao, Woon-Puay Koh, Yong-Bing Xiang, Ze-Zhong Tang, Jin-Hu Fan, Jing-jing Han, Sheng-Li Zhou, Peng Zhang, Dong-Yun Zhang, Yuan Yuan, Ying Huang, Chunling Liu, Kan Zhai, Yan Qiao, Guangfu Jin, Chuanhai Guo, Jianhua Fu, Xiaoping Miao, Changdong Lu, Haijun Yang, Chaoyu Wang, William A Wheeler, Mitchell Gail, Meredith Yeager, Jeff Yuenger, Er-Tao Guo, Ai-li Li, Wei Zhang, Xue-Min Li, Liang-Dan Sun, Bao-Gen Ma, Yan Li, Sa Tang, Xiu-Qing Peng, Jing Liu, Amy Hutchinson, Kevin Jacobs, Carol Giffen, Laurie Burdette, Joseph F Fraumeni, Hongbing Shen, Yang Ke, Yixin Zeng, Tangchun Wu, Peter Kraft, Charles C Chung, Margaret A Tucker, Zhi-Chao Hou, Ya-Li Liu, Yan-Long Hu, Li Wang, Guo Yuan, Li-Sha Chen, Xiao Liu, Teng Ma, Hui Meng, Li Sun, Xin-Min Li, Xiu-Min Li, Jian-Wei Ku, Ying-Fa Zhou, Liu-Qin Yang, Zhou Wang, Yin Li, Qirenwang Qige, Wen-jun Yang, Guang-Yan Lei, Long-qi Chen, En-Min Li, Ling Yuan, Wen-Bin Yue, Ran Wang, Lu-Wen Wang, Xue-Ping Fan, Fang-Heng Zhu, Wei-Xing Zhao, Yi-min Mao, Mei Zhang, Guo-Lan Xing, Ji-Lin Li, Min Han, Jing-Li Ren, Bin Liu, Shu-Wei Ren, Qing-Peng Kong, Feng Li, Ilyar Sheyhidin, Wu Wei, Yan-Rui Zhang, Chang-Wei Feng, Jin Wang, Yu-Hua Yang, Hong-Zhang Hao, Qi-De Bao, Bao-Chi Liu, Ai-Qun Wu, Dong Xie, Wan-Cai Yang, Liang Wang, Xiao-Hang Zhao, Shu-Qing Chen, Jun-Yan Hong, Xue-Jun Zhang, Neal D Freedman, Alisa M Goldstein, Dongxin Lin, Philip R Taylor, Li-dong Wang, Stephen J Chanock.
Nat. Genet.
PUBLISHED: 08-17-2014
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We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) of esophageal squamous cell carcinoma (ESCC) in individuals of Chinese ancestry (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.82-0.88; P = 7.72 × 10(-20)) and rs1642764 at 17p13.1 (per-allele OR = 0.88, 95% CI = 0.85-0.91; P = 3.10 × 10(-13)). rs7447927 is a synonymous SNP in TMEM173, and rs1642764 is an intronic SNP in ATP1B2, near TP53. Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR = 1.33, 95% CI = 1.22-1.46; P = 1.99 × 10(-10)). Our joint analysis identifies new ESCC susceptibility loci overall as well as a new locus unique to the population in the Taihang Mountain region at high risk of ESCC.
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Discovery of common sequences absent in the human reference genome using pooled samples from next generation sequencing.
BMC Genomics
PUBLISHED: 08-16-2014
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Sequences up to several megabases in length have been found to be present in individual genomes but absent in the human reference genome. These sequences may be common in populations, and their absence in the reference genome may indicate rare variants in the genomes of individuals who served as donors for the human genome project. As the reference genome is used in probe design for microarray technology and mapping short reads in next generation sequencing (NGS), this missing sequence could be a source of bias in functional genomic studies and variant analysis. One End Anchor (OEA) and/or orphan reads from paired-end sequencing have been used to identify novel sequences that are absent in reference genome. However, there is no study to investigate the distribution, evolution and functionality of those sequences in human populations.
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Synthesis and analgesic effects of ?-TRTX-Hhn1b on models of inflammatory and neuropathic pain.
Toxins (Basel)
PUBLISHED: 08-13-2014
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?-TRTX-Hhn1b (HNTX-IV) is a 35-amino acid peptide isolated from the venom of the spider, Ornithoctonus hainana. It inhibits voltage-gated sodium channel Nav1.7, which has been considered as a therapeutic target for pain. The goal of the present study is to elucidate the analgesic effects of synthetic ?-TRTX-Hhn1b on animal models of pain. The peptide was first synthesized and then successfully refolded/oxidized. The synthetic peptide had the same inhibitory effect on human Nav1.7 current transiently expressed in HEK 293 cells as the native toxin. Furthermore, the analgesic potentials of the synthetic peptide were examined on models of inflammatory pain and neuropathic pain. ?-TRTX-Hhn1b produced an efficient reversal of acute nociceptive pain in the abdominal constriction model, and significantly reduced the pain scores over the 40-min period in the formalin model. The efficiency of ?-TRTX-Hhn1b on both models was equivalent to that of morphine. In the spinal nerve model, the reversal effect of ?-TRTX-Hhn1b on allodynia was longer and higher than mexiletine. These results demonstrated that ?-TRTX-Hhn1b efficiently alleviated acute inflammatory pain and chronic neuropathic pain in animals and provided an attractive template for further clinical analgesic drug design.
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Prognostic role of CD44 expression in osteosarcoma: evidence from six studies.
Diagn Pathol
PUBLISHED: 08-11-2014
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Numerous studies examining the relationship between CD44 expression and prognostic impact in patients with osteosarcoma have yielded inconclusive results. The aim of this meta-analysis was carried out to investigate the relationship between CD44 expression and the survival in patients with osteosarcoma.
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[Derivative synchronous fluorimetry for determination of synthetic food dyes in food].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 08-07-2014
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The first order derivative synchronous fluoremetry was proposed for simultaneous determination of sunset yellow and ponceau 4R The effect of different experimental conditions, such as different pH for character of fluorescence spectra and the choosing of the optimal wavelength difference were studied. It was showed that the zero-crossing points were at 313. 6 nm for ponceau 4R and at 302. 8 nm for sunset yellow in first order derivative synchronous fluorescence spectra. Therefore, 313. 6 and 302. 8 nm were selected for the determination of sunset yellow and ponceau 4R when delta lambda= 130 nm. This method could minimize interference without preseparation. The linear ranges of sunset yellow and ponceau 4R were from 0. 1 to 2. 0 mg L-1 and from 0. 1 to 4. 0 mg L-1 with correlation coefficient 0. 996 6 and 0. 999 2, the detection limits were 0. 041 and 0. 019 mg L-1 , RS-Ds were 4. 6% and 4. 8% (n=6), respectively. The recoveries varied from 91. 0% to 110%. The proposed method was successfully applied in simultaneous determination of sunset yellow and Ponceau 4R in food.
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A high-throughput adrenaline test for the exploration of the catalytic potential of halohydrin dehalogenases in epoxide-ring opening reactions.
Biotechnol. Appl. Biochem.
PUBLISHED: 08-02-2014
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The principle of the adrenaline test for enzymes is based on the quantification of periodate-sensitive reaction products with adrenaline to produce a chromogenic compound adrenochrome that can be easily detected. Here a rapid whole cell-based adrenaline assay for the activity measurement of halohydrin dehalogenases (HHDHs) in nucleophile mediated epoxide-opening reactions is presented. The assay was validated using two types of model reactions (glycidol with nucleophiles, and nitrite with epoxides). Moreover, the reliability of the assay was confirmed by GC analysis. Our results demonstrated that the developed assay is efficient in both library screening and the evaluation of catalytic diversity and specificity of HHDHs. Thus, the assay represents a valuable tool in the evolution of HHDHs for its industrial applications. Moreover, the adrenaline test exhibits a great potential for enzyme assay and could be easily adopted for other suitable enzymes. This article is protected by copyright. All rights reserved.
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Structure and thermodynamic properties of relativistic electron gases.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 07-30-2014
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Relativistic effect is important in many quantum systems but theoretically complicated from both fundamental and practical perspectives. Herein we introduce an efficient computational procedure to predict the structure and energetic properties of relativistic quantum systems by mapping the Pauli principle into an effective pairwise-additive potential such that the properties of relativistic nonquantum systems can be readily predicted from conventional liquid-state methods. We applied our theoretical procedure to relativistic uniform electron gases and compared the pair correlation functions with those for systems of nonrelativistic electrons. A simple analytical expression has been developed to correlate the exchange-correlation free energy of relativistic uniform electron systems.
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Large-area binary blazed grating coupler between nanophotonic waveguide and LED.
ScientificWorldJournal
PUBLISHED: 07-13-2014
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A large-area binary blazed grating coupler for the arrayed waveguide grating (AWG) demodulation integrated microsystem on silicon-on-insulator (SOI) was designed for the first time. Through the coupler, light can be coupled into the SOI waveguide from the InP-based C-band LED for the AWG demodulation integrated microsystem to function. Both the length and width of the grating coupler are 360 ?m, as large as the InP-based C-band LED light emitting area in the system. The coupler was designed and optimized based on the finite difference time domain method. When the incident angle of the light source is 0°, the coupling efficiency of the binary blazed grating is 40.92%, and the 3 dB bandwidth is 72 nm at a wavelength of 1550 nm.
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Synthesis and Photophysical Behavior of a Supramolecular Nanowire made from Dithienylethene-Bridged Bis(permethyl-?-cyclodextrin)s and Porphyrins.
Chem Asian J
PUBLISHED: 07-09-2014
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A photochromic dithienylethene-bridged bis(permethyl-?-cyclodextrin)s was successfully synthesized through an amide condensation reaction, and its photochromic properties were also investigated by (1) H?NMR spectra and UV/vis spectroscopy. Moreover, taking advantage of the strong interaction between permethyl-?-cyclodextrin and water soluble porphyrins, a supramolecular nanowire was then successfully constructed and characterized by UV/vis spectroscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Significantly, the fluorescence resonance energy transfer (FRET) process from the porphyrin to the dithienylethene core can be modulated by alternate irradiation with ultraviolet and visible light and, thus, light-controlled quenching and recovery of fluorescence of porphyrins was realized.
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Multistimuli-responsive supramolecular assembly of cucurbituril/cyclodextrin pairs with an azobenzene-containing bispyridinium guest.
Chemistry
PUBLISHED: 07-02-2014
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A linear supramolecular architecture was successfully constructed by the inclusion complexation of ?-cyclodextrin with azobenzene and the host-stabilized charge-transfer interaction of naphthalene and a bispyridinium guest with cucurbit[8]uril in water, which was comprehensively characterized by (1) H?NMR spectroscopy, UV/Vis absorption, fluorescence, circular dichroism spectroscopy, dynamic laser scattering, and microscopic observations. Significantly, because it benefits from the photoinduced isomerization of the azophenyl group and the chemical reduction of bispyridinium moiety with noncovalent connections, the assembly/disassembly process of this supramolecular nanostructure can be efficiently modulated by external stimuli, including temperature, UV and visible-light irradiation, and chemical redox.
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Integrating phosphoproteomics in systems biology.
Comput Struct Biotechnol J
PUBLISHED: 07-01-2014
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Phosphorylation of serine, threonine and tyrosine plays significant roles in cellular signal transduction and in modifying multiple protein functions. Phosphoproteins are coordinated and regulated by a network of kinases, phosphatases and phospho-binding proteins, which modify the phosphorylation states, recognize unique phosphopeptides, or target proteins for degradation. Detailed and complete information on the structure and dynamics of these networks is required to better understand fundamental mechanisms of cellular processes and diseases. High-throughput technologies have been developed to investigate phosphoproteomes in model organisms and human diseases. Among them, mass spectrometry (MS)-based technologies are the major platforms and have been widely applied, which has led to explosive growth of phosphoproteomic data in recent years. New bioinformatics tools are needed to analyze and make sense of these data. Moreover, most research has focused on individual phosphoproteins and kinases. To gain a more complete knowledge of cellular processes, systems biology approaches, including pathways and networks modeling, have to be applied to integrate all components of the phosphorylation machinery, including kinases, phosphatases, their substrates, and phospho-binding proteins. This review presents the latest developments of bioinformatics methods and attempts to apply systems biology to analyze phosphoproteomics data generated by MS-based technologies. Challenges and future directions in this field will be also discussed.
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The Protective Effect of Epoxyeicosatrienoic Acids on Cerebral Ischemia/Reperfusion Injury is Associated with PI3K/Akt Pathway and ATP-Sensitive Potassium Channels.
Neurochem. Res.
PUBLISHED: 06-18-2014
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Epoxyeicosatrienoic acids (EETs), the cytochrome P450 epoxygenase metabolite of arachidonic acid, have been demonstrated to have neuroprotective effect. Phosphatidylinositol 3-kinase (PI3K)/Akt and ATP-sensitive potassium (KATP) channels are thought to be important factors that mediate neuroprotection. However, little is known about the role of PI3K/Akt and KATP channels in brain after EETs administration. In vitro experiment, oxygen-glucose deprivation (OGD) was performed in cultured rat cerebral microvascular smooth muscle cells (SMCs) for 4 h. The effect of 14,15-EET on OGD induced cell apoptosis was examined after reoxygenation. Western blot and real-time PCR were used to analyze the expression of Kir6.1, SUR2B (two subunits of KATP channels) and p-Akt on cerebral microvascular SMCs. In vivo experiments, we use 12-(3-adamantan-1-yl-ureido)-dodecanoic acid [AUDA, a specific soluble epoxide hydrolase (sEH) inhibitor] to confirm the effect of EETs indirectly. Rats were injected intraperitoneally with AUDA before being subjected to middle cerebral artery occlusion (MCAO). We detected the apoptosis and the expression of p-Akt, Kir6.1 and SUR2B in ischemic penumbra. The results showed that EETs protect against cerebral ischemia/reperfusion (I/R) injury and upregulated the expression of p-Akt and Kir6.1 in both of ischemic penumbra and OGD induced cerebral microvascular SMCs. The protective effect was inhibited by Wortmannin (a specific PI3K inhibitor) and Glib (a specific KATP inhibitor) respectively in vitro experiment. In conclusion, these results suggested that the protective effect of EETs on cerebral I/R injury is associated with PI3K/Akt pathway and KATP channels. Furthermore, the PI3K pathway may contribute to mediating KATP channels on cerebral microvascular SMCs.
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General incorporation of diverse components inside metal-organic framework thin films at room temperature.
Nat Commun
PUBLISHED: 06-16-2014
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Porous metal-organic frameworks (MOFs) demonstrate great potential for numerous applications. Although hetero-functional components have been encapsulated within MOF crystalline particles, the uniform incorporation of functional species with different sizes, shapes and functions in MOF thin films with dual properties, especially at room temperature and without the degradation of the MOF framework, remains a significant challenge towards further enriching their functions for various purposes. Here we report a general method that can rapidly encapsulate diverse functional components, including small ions, micrometre-sized particles, inorganic nanoparticles and bioactive proteins, in MOF thin films at room temperature via a metal-hydroxide-nanostrand-assisted confinement technique. These functional component-encapsulated MOF composite thin films exhibit synergistic and size-selective catalytic, bio-electrochemical, conductive and flexible functionalities that are desirable for thin film devices, including catalytic membrane reactors, biosensors and flexible electronic devices.
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Next-generation RNA Sequencing of Archival Formalin-fixed Paraffin-embedded Urothelial Bladder Cancer.
Eur. Urol.
PUBLISHED: 06-13-2014
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Molecular profiling of individual cancers is key to personalised medicine. While sequencing technologies have required stringent sample collection and handling, recent technical advances offer sequencing from tissues collected in routine practice and tissues already stored in archives. In this paper, we establish methods for whole-transcriptome RNA sequencing (RNA-seq) from formalin-fixed paraffin-embedded tissues. We obtain average RNA-seq reads of >100 million per sample using the Illumina HiSeq2000 platform. We find high concordance with results from matching fresh frozen samples (>0.8 Spearman correlation). For validation, we compared low- and high-grade bladder cancer transcriptomes in 49 tumour samples after transurethral resection of bladder tumour. We found 947 differentially expressed protein-coding genes. While high-grade lesions exhibited distinct intertumour transcriptome heterogeneity, the transcriptome of low-grade tumours was homogeneous.
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Electrophysiological effect of rotigaptide in rabbits with heart failure.
Arch Med Sci
PUBLISHED: 06-07-2014
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Rotigaptide is a new anti-arrhythmic peptide, which has recently been found to increase junctional conductance and prevent ischemia-induced ventricular tachycardia. In this study, we attempted to investigate the effects and mechanisms of rotigaptide on the vulnerability to ventricular arrhythmias in rabbits with heart failure (HF).
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One-pot, One-step Synthesis of 2,5-Diformylfuran from Carbohydrates over Mo-Containing Keggin Heteropolyacids.
ChemSusChem
PUBLISHED: 05-26-2014
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In this work, a one-pot strategy for directly converting fructose into 2,5-diformylfuran (DFF) over Mo-containing Keggin heteropolyacids (HPAs) in open air is developed. H3 PMo12 O40 HPA is found to show high activity and selectivity to the formation of DFF owing to its higher Brønsted acidity and moderate redox potential. The partial substitution of the H(+) in H3 PMo12 O40 with Cs(+) leads to the heterogenization of the HPA by forming its cesium salts Csx H3-x PMo12 (x=0.5, 1.5, and 2.5). A satisfactory yield of 69.3?% to DFF is obtained over Cs0.5 H2.5 PMo12 polyoxometalate after deliberate optimization of the reaction conditions. The heterogenized polyoxometalate could be recycled and reused without significant loss of catalytic activity for five runs. The produced DFF could be separated from the resulting mixture by an adsorption-desorption method using activated carbon as the adsorbent and furfural as the desorbent. A highest isolated yield of 58.2?% is obtained.
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Motor preparation attenuates neural variability and beta-band LFP in parietal cortex.
Sci Rep
PUBLISHED: 05-14-2014
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Accumulative evidence shows that neural variability is meaningful and powerful during brain information processing, but how cognitive state influences neural variability is still unclear. We studied neural variability during motor preparation in lateral intraparietal area (LIP), a brain area closely involved in saccade generation. During motor preparation, we observed significant variability decline, and the decline highly correlated with beta-band local field potential (LFP) fluctuations. Furthermore, we found similar variance-LFP correlations in both the memory-guided saccade task and the visually-guided saccade task. These results indicate a possible linkage between beta-band LFP and trial-to-trial neural variability.
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Silk fibroin nanoparticles prepared by electrospray as controlled release carriers of cisplatin.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 04-29-2014
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To maintain the anti-tumor activity of cis-dichlorodiamminoplatinum (CDDP) while avoiding its cytotoxicity and negative influence on normal tissue, CDDP-loaded silk fibroin nanoparticles approximately 59nm in diameter were successfully prepared by electrospray without using organic solvent. CDDP was incorporated into nanoparticles through metal-polymer coordination bond exchange. In vitro release tests showed that the cisplatin in the nanoparticles could be slowly and sustainably released for more than 15days. In vitro anti-cancer experiments and intracellular Pt content testing indicated that CDDP-loaded silk fibroin nanoparticles were easily internalized by A549 lung cancer cells, transferring CDDP into cancer cells and then triggering their apoptosis. In contrast, the particles were not easily internalized by L929 mouse fibroblast cells and hence showed weaker cell growth inhibition. The CDDP-loaded silk fibroin nanoparticles showed sustained and efficient killing of tumor cells but weaker inhibition of normal cells. In general, this study provides not only a novel method for preparing CDDP-loaded silk fibroin nanoparticles but also a new carrier system for clinical therapeutic drugs against lung cancers and other tumors.
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RNAIII suppresses the expression of LtaS via acting as an antisense RNA in Staphylococcus aureus.
J. Basic Microbiol.
PUBLISHED: 04-25-2014
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RNAIII is known as the key effector of staphylococcal accessory gene regulator (agr) quorum-sensing system, which plays a central role in the pathogenesis of Staphylococcus aureus. As a regulatory RNA, RNAIII regulates multiple targets, including exoproteins and cell-wall-associated proteins. Lipoteichoic acid synthase (LtaS) is involved in the synthesis of lipoteichoic acid (LTA) that is one of the major components of cell wall. The chemical compound targeting to LtaS decreases S. aureus growth via blocking LTA production. Until now, the regulatory mechanism of LtaS expression is still not clear. The level of ltaS mRNA in S. aureus is analyzed by semi-quantitative RT-PCR analysis and qRT-PCR. The protein level of LtaS is determined by Western blotting. The putative interaction sites between RNAIII and LtaS mRNA are predicted. And LtaS-5'UTR-lacZ and LtaS-5'UTR-mutant-lacZ reporter vectors are constructed according to the putative interaction sites. Our data show that the expression of ltaS is regulated by RNAIII in S. aureus. The level of LtaS is significantly higher in the RNAIII deficient strain compared to its parent strain. In the further investigation, 5'UTR of ltaS was predicted to be the putative interaction site of RNAIII. The results of detection of ?-galactosidase activities suggest that RNAIII can inhibit the expression level of LtaS through acting on the 5'UTR region of LtaS mRNA. Our finding presents that LtaS is another target of RNAIII and RNAIII suppresses the expression of LtaS via acting as an antisense RNA in S. aureus.
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MicroRNA-185 inhibits proliferation by targeting c-Met in human breast cancer cells.
Exp Ther Med
PUBLISHED: 04-02-2014
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MicroRNAs (miRNAs) are a group of small non-coding RNA molecules that have been shown to regulate the expression of genes involved in tumorigenesis. The relevance of miRNAs in the development, progression and prognosis of human breast cancer is not fully understood. miR-185 has been demonstrated to be involved in the pathogenesis of several types of cancers; however, its role in breast cancer has not yet been elucidated. In the present study, the expression of miR-185 was analyzed by quantitative polymerase chain reaction. In addition, an MTT assay and flow cytometry were used to determine the rates of cell proliferation and apoptosis. Protein expression was analyzed by western blotting and the target gene was confirmed using a luciferase reporter assay. The expression of miR-185 was found to be downregulated in the breast cancer tissues. The MTT assay revealed that overexpression of miR-185 inhibited the proliferation of MDF7 and SKBR3 cells. Furthermore, flow cytometric analysis demonstrated that increased expression levels of miR-185 promoted the apoptosis of breast cancer cells. In addition, c-Met expression was demonstrated to be significantly upregulated in breast cancer tissues and cells, and the c-Met gene was identified to be a target of miR-185. Therefore, the results demonstrated that miR-185 inhibited the proliferation of breast cancer cells by regulating the expression of c-Met, indicating its potential as a therapeutic target for breast cancer.
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Serum-free medium optimization based on trial design and support vector regression.
Biomed Res Int
PUBLISHED: 03-17-2014
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The Plackett-Burman design and support vector machine (SVM) were reported to be used on many fields such as some feature selections, protein structure prediction, or forecasting of other situations. Here, with suspension adapted Chinese hamster ovary (CHO) cells as the object of study, a serum-free medium for the culture of CHO cells in suspension was optimized by this method. Support vector machine based on genetic algorithm was used to predict the growth rate of CHO and prove the results from the trial designs. Experimental results indicated that ZnSO4, transferrin, and bovine serum albumin (BSA) were important ones. The same conclusion was arrived at when the support vector regression model analyzed the experimental results. With the methods mentioned, the influence of 7 medium supplements on the growth of CHO cells in suspension was evaluated efficiently.
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Protective Effects of Poly (butyl) Cyanoacrylate Nanoparticles Containing Vasoactive Intestinal Peptide Against 6-Hydroxydopamine-Induced Neurotoxicity In Vitro.
J. Mol. Neurosci.
PUBLISHED: 03-04-2014
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The present study investigated brain delivery system of vasoactive intestinal peptide (VIP) adsorbed on poly (butyl cyanoacrylate) nanoparticles coated with polysorbate 80 (P80-poly (butyl) cyanoacrylate (PBCA)-nanoparticles (NPs)) and the neuroprotective effects on the formulation in the model of 6-hydroxydopamine (6-OHDA)-induced Parkinsonian dysfunction in the human neuroblastoma cell line SH-SY5Y. Drug-loaded nanoparticles were prepared by emulsion polymerization method using VIP and PBCA and then stirring with polysorbate 80. The resulting nanoparticles possessed high entrapment efficiency and favorable stability against CaCl2 or fetal bovine serum (FBS)-induced aggregation. Use of fluorescein isothiocyanate (FITC)-conjugated polysorbate 80-PBCA nanoparticles in confocal microscopy revealed that nanoparticles are located inside, while the FITC solution could not penetrate into the cells. The blank nanoparticles showed no significant effects on cell viability, indicating that they had no role in protection; however, polysorbate 80-modified VIP-loading PBCA nanoparticles showed enhanced cell viability compared to free VIP in 6-OHDA-mimic cellular model of Parkinson's disease. In addition, the nanoparticles strikingly increased the anti-apoptosis activity and restored the loss of mitochondrial membrane potential (MMP) significantly after the treatment of 6-OHDA. These results demonstrated that the activity of VIP was enhanced by polysorbate 80-PBCA nanoparticles compared to control solutions, suggesting that PBCA nanoparticles coated with polysorbate 80 could be an effective carrier system for VIP.
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Reduced endoplasmic reticulum stress might alter the course of heart failure via caspase-12 and JNK pathways.
Can J Cardiol
PUBLISHED: 02-26-2014
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Endoplasmic reticulum (ER) stress plays an important role in mediating ischemic heart cell death. The aim of this study was to investigate whether manipulation of a key factor of the ER stress pathway, eukaryotic translation initiation factor 2 subunit ? (eIF2?), can change the natural history of heart failure (HF).
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Comparison of scaled-average, population, and individual bioequivalence on 2 tablets of pitavastatin calcium: a 3-period, reference-replicated, crossover study in healthy Chinese volunteers.
Clin Ther
PUBLISHED: 02-24-2014
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Pitavastatin, a fully synthetic ?-hydroxy-?-methylglutaryl-coenzyme A reductase inhibitor, is potent for the treatment of primary hyperlipidemia and mixed dyslipidemia. Recently, the original product and some generic products of pitavastatin calcium have become available in China. However, the intrasubject variability and interchangeability of this newly developed generic product and the branded innovator product have rarely been investigated in the Chinese population.
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Soil-borne pathogens restrict the recruitment of a subtropical tree: a distance-dependent effect.
Oecologia
PUBLISHED: 02-07-2014
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The Janzen-Connell hypothesis suggests that density- and/or distance-dependent juvenile mortality driven by host-specific natural enemies can explain high species diversity in tropical forests. However, such density and distance effects may not occur simultaneously and may not be driven by the same mechanism. Also, reports of attempts to identify and quantify the differences between these processes in tropical forests are scarce. In a primary subtropical forest in China, we (1) experimentally examined the relative influence of the distance to parent trees vs. conspecific seedling density on mortality patterns in Engelhardia fenzelii, (2) tested the role of soil-borne pathogens in driving density- or distance-dependent processes that cause seedling mortality, and (3) inspected the susceptibilities of different tree species to soil biota of E. fenzelii and the effects of soil biota from different tree species on E. fenzelii. The results from these field experiments showed that distance- rather than density-dependent processes driven by soil pathogens strongly affect the seedling survival of this species in its first year. We also observed increased survival of a fungicide treatment for E. fenzelii seedlings in the parent soil but not for the seedlings of the other three species in the E. fenzelii parent soil, or for E. fenzelii seedlings in the parent soil of three other species. This study illustrates how the distance-dependent pattern of seedling recruitment for this species is driven by soil pathogens, a mechanism that likely restricts the dominance of this abundant species.
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Membrane Distillation Bioreactor (MDBR) - A lower Green-House-Gas (GHG) option for industrial wastewater reclamation.
Chemosphere
PUBLISHED: 02-07-2014
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A high-retention membrane bioreactor system, the Membrane Distillation Bioreactor (MDBR) is a wastewater reclamation process which has the potential to tap on waste heat generated in industries to produce high quality product water. There are a few key factors which could make MDBR an attractive advanced treatment option, namely tightening legal requirements due to increasing concerns on the micropollutants in industrial wastewater effluents as well as concerns over the electrical requirement of pressurized advanced treatment processes and greenhouse gas emissions associated with wastewater reclamation. This paper aims to provide a consolidated review on the current state of research for the MDBR system and to evaluate the system as a possible lower Green House Gas (GHG) emission option for wastewater reclamation using the membrane bioreactor-reverse osmosis (MBR-RO) system as a baseline for comparison. The areas for potential applications and possible configurations for MDBR applications are discussed.
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Tai Ji Quan and global cognitive function in older adults with cognitive impairment: a pilot study.
Arch Gerontol Geriatr
PUBLISHED: 01-09-2014
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This study evaluated whether Tai Ji Quan: Moving for Better Balance (TJQMBB) could improve global cognitive function in older adults with cognitive impairment. Using a nonrandomized control group pretest-posttest design, participants aged ?65 years who scored between 20 and 25 on the Mini-Mental State Examination (MMSE) were allocated into either a 14-week TJQMBB program (n=22) or a control group (n=24). The primary outcome was MMSE as a measure of global cognitive function with secondary outcomes of 50-ft speed walk, Timed Up&Go, and Activities-Specific Balance Confidence (ABC) scale. At 14 weeks, Tai Ji Quan participants showed significant improvement on MMSE (mean=2.26, p<0.001) compared to controls (mean=0.63, p=0.08). Similarly, Tai Ji Quan participants performed significantly better compared to the controls in both physical performance and balance efficacy measures (p<0.05). Improvement in cognition as measured by MMSE was related to improved physical performance and balance efficacy. These results provide preliminary evidence of the utility of the TJQMBB program to promote cognitive function in older adults in addition to physical benefits.
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Biomass-derived highly porous functional carbon fabricated by using a free-standing template for efficient removal of methylene blue.
Bioresour. Technol.
PUBLISHED: 01-07-2014
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Banana peel (BP), a biomass waste, was converted into a valuable highly porous functional carbon material (HPFCM) by a general chelate-assisted co-assembly process. The HPFCMs were fabricated by using Al(III)-based metal-organic framework-like as a free-standing template and commercial Pluronic F127 as a microstructure-directing agent. Several critical variables for fabrication including doses of Al(III) and F127, carbonization temperature had been optimized and the adsorption behavior of HPFCMs was examined by using methylene blue as dye model compound. The optimal adsorbent was validated as HPFCMs-5-1-800, and its equilibrium data were well fitted to the Langmuir isotherm model with a monolayer adsorption capacity of 385.12 mg g(-1) at ambient temperature. The surface physical properties of HPFCMs-5-1-800 were also exemplarily characterized. The findings revealed that the free-standing template is a potential route for preparation of HPFCM from waste BP.
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Elevation of peripheral BDNF promoter methylation links to the risk of Alzheimer's disease.
PLoS ONE
PUBLISHED: 01-01-2014
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Brain derived neurotrophic factor (BDNF) has been known to play an important role in various mental disorders or diseases such as Alzheimer's disease (AD). The aim of our study was to assess whether BDNF promoter methylation in peripheral blood was able to predict the risk of AD. A total of 44 AD patients and 62 age- and gender-matched controls were recruited in the current case-control study. Using the bisulphite pyrosequencing technology, we evaluated four CpG sites in the promoter of the BDNF. Our results showed that BDNF methylation was significantly higher in AD cases than in the controls (CpG1: p?=?10.021; CpG2: p?=?0.002; CpG3: p?=?0.007; CpG4: p?=?0.005; average methylation: p?=?0.004). In addition, BDNF promoter methylation was shown to be significantly correlated with the levels of alkaline phosphatase (ALP), glucose, Lp(a), ApoE and ApoA in males (ALP: r?=?-0.308, p?=?0.042; glucose: r?=?-0.383, p?=?0.010; Lp(a): r?=?0.333, p?=?0.027; ApoE: r?=?-0.345, p?=?0.032;), ApoA levels in females (r?=?0.362, p?=?0.033), and C Reactive Protein (CRP) levels in both genders (males: r?=?-0.373, p?=?0.016; females: r?=?-0.399, p?=?0.021). Our work suggested that peripheral BDNF promoter methylation might be a diagnostic marker of AD risk, although its underlying function remains to be elaborated in the future.
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Podocalyxin Promotes Glioblastoma Multiforme Cell Invasion and Proliferation via ?-Catenin Signaling.
PLoS ONE
PUBLISHED: 01-01-2014
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Both podocalyxin (PODX) and ?-catenin (?-cat) signaling reportedly play important roles in glioblastoma multiforme (GBM) progression. In this study, we for the first time explored crosstalk between PODX and ?-cat signaling in GBM cells, and assessed its impact on GBM cell invasion and proliferation. Stable overexpression of PODX in LN-229 and U-118 MG human GBM cells increased the soluble/intracellular ?-cat level, TOPflash luciferase reporter activity, the mRNA levels of ?-cat signaling target genes, matrix metalloproteinase 9 (MMP9) expression/activity, and cell invasion and proliferation, which was abolished by selective p38 mitogen-activated protein kinase (MAPK) inhibitor PD169316 and selective ?-cat signaling inhibitor CCT031374. On the other hand, stable knockdown of PODX in LN-229 and U-118 MG cells decreased the soluble ?-cat level, TOPflash luciferase reporter activity, the mRNA levels of ?-cat signaling target genes, MMP9 expression/activity, and cell invasion and proliferation, which was completely reversed by overexpression of a constitutively active ?-cat mutant. In addition, overexpression of PODX induced p38 MAPK activity and inactivating phosphorylation of glycogen synthase kinase-3? (GSK-3?) at serine 389 in LN-229 and U-118 MG cells, which was abolished by PD169316, but not CCT031374; knockdown of PODX decreased p38 MAPK activity and inactivating phosphorylation of GSK-3? at serine 389 in both cell lines, which was not significantly affected by overexpression of constitutively active ?-cat. In conclusion, this study indicates that PODX promotes GBM cell invasion and proliferation by elevating the soluble ?-cat level/?-cat signaling through the p38 MAPK/GSK-3? pathway. Uncovering the PODX/?-cat signaling axis adds new insights not only into the biological functions of PODX and ?-cat, but also into the molecular mechanisms underlying GBM progression.
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Prognostic value of preoperative inflammatory markers in Chinese patients with breast cancer.
Onco Targets Ther
PUBLISHED: 01-01-2014
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Cancer-associated inflammation is a key determinant of disease progression and survival in most cancers. The aim of our study was to assess the predictive value of preoperative inflammatory markers, such as the neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio, red cell distribution width (RDW), and mean platelet volume, for survival in breast cancer patients. In total, 608 breast cancer patients operated on between January 2009 and December 2011 were included in this observational study. The association between preoperative inflammatory markers and survival outcomes was analyzed. Patients with high NLR (>2.57) or high RDW (>13.45%) showed a significantly lower overall survival rate than those with lower NLR (?2.57) or lower RDW (?13.45%). NLR and RDW, along with node stage and molecular subtypes, were independent prognostic factors. There was a significant survival difference according to NLR in the luminal A and triple-negative subtypes (93.3% versus 99.3%, P=0.001; 68.8% versus 95.1%, P=0.000, respectively). The triple-negative subtype was the only subtype in which higher RDW patients showed significantly poor prognosis (81.3% versus 95.5%, P=0.025). Pre-operation NLR and RDW is a convenient, easily measured prognostic indicator for patients with breast cancer, especially in patients with the triple-negative subtype.
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Observation of anomalous linear photogalvanic effect and its dependence on wavelength in undoped InGaAs/AlGaAs multiple quantum well.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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We observed an anomalous linear photogalvanic effect (ALPGE) in undoped InGaAs/AlGaAs multiple quantum well and studied its wavelength dependence in details. This effect is believed to originate from the optical momentum alignment effect and the inhomogeneity of light intensity. We find that the spot location with the maximum ALPGE current is wavelength independent. And the normalized ALPGE current decreasing at smaller wavelengths is attributed to the sharp decrease of the momentum and energy relaxation time. The electrical measurement of the spectra dependence of ALPGE is highly sensitive proving to be an effective method for detecting the momentum anisotropy of photoinduced carriers and band coupling.
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Electrospun fibrous scaffolds combined with nanoscale hydroxyapatite induce osteogenic differentiation of human periodontal ligament cells.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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Periodontal repair is a complex process in which regeneration of alveolar bone is a vital component. The aim of this study was to develop a biodegradable scaffold with good biocompatibility and osteoinductive ability. Two types of composite fibrous scaffolds were produced by electrospinning, ie, type I collagen/poly(?-caprolactone) (COL/PCL) and type I collagen/poly(?-caprolactone)/nanoscale hydroxyapatite (COL/PCL/nHA) with an average fiber diameter of about 377 nm. After a simulated body fluid (SBF) immersion test, the COL/PCL/nHA-SBF scaffold developed a rough surface because of the calcium phosphate deposited on the fibers, suggesting that the presence of nHA promoted the mineralization potential of the scaffold. Energy dispersive X-ray spectroscopy clearly showed the calcium and phosphorus content in the COL/PCL/nHA and COL/PCL/nHA-SBF scaffolds, confirming the findings of nHA and calcium phosphate precipitation on scanning electron micrographs. Water contact analysis revealed that nHA could improve the hydrophilic nature of the COL/PCL/nHA-SBF scaffold. The morphology of periodontal ligament cells cultured on COL/PCL-SBF and COL/PCL/nHA-SBF was evaluated by scanning electron microscopy. The results showed that cells adhered to either type of scaffold and were slightly spindle-shaped in the beginning, then extended gradually with stretched filopodia, indicating an ability to fill the fiber pores. A Cell Counting Kit-8 assay showed that both scaffolds supported cell proliferation. However, real-time quantitative polymerase chain reaction analysis showed that expression of the bone-related markers, alkaline phosphatase and osteocalcin, was upregulated only on the COL/PCL/nHA-SBF scaffold, indicating that this scaffold had the ability to induce osteogenic differentiation of periodontal ligament cells. In this study, COL/PCL/nHA-SBF produced by electrospinning followed by biomimetic mineralization had combined electrospun fibers with nHA in it. This scaffold has good biocompatibility and osteoinductive ability as a result of the characteristics of nHA, so could be innovatively applied to periodontal tissue engineering as a potential scaffold.
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Combination of high ankle-brachial index and hard coronary heart disease Framingham Risk Score in predicting the risk of ischemic stroke in general population.
PLoS ONE
PUBLISHED: 01-01-2014
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Our previous study showed that the patients with more metabolic risk factors had higher risk of high ankle-brachial index (ABI), but the relationship between high ABI and the risk of severe cardiovascular and cerebrovascular diseases is still under debate. This study aims to evaluate this association in the general population. 1486 subjects of South China were recruited in the study. 61 subjects were defined as high ABI group (ABI?1.3) and 65 subjects were randomly selected as normal ABI group (0.9
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[Biomass and carbon storage of Phragmites australis and Spartina alterniflora in Jiuduan Shoal Wetland of Yangtze Estuary, East China].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
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By the methods of field survey and laboratory analysis, an investigation was conducted on the seasonal dynamics of biomass and carbon storage of Phragmites australis and Spartina alterniflora dominated vegetation belts in the Jiuduan Shoal Wetland of Yangtze Estuary, East China in 2010-2012. The organic carbon storage of the biomass (including aboveground part, underground part, and standing litter) of the two plants was the highest in autumn and the lowest in spring. The average carbon storage of the biomass of S. alterniflora per unit area (445.81 g x m(-2)) was much higher than that of P. australis (285.52 g x m(-2)), and the average carbon storage of the standing litter of S. alterniflora (315.28 g x m(-2)) was also higher than that of P. australia (203.15 g x m(-2)). However, the organic carbon storage in the surface soil (0-30 cm) under P. australis community (1048.62 g x m(-2)) was almost as twice times as that under S. alterniflora community (583.33 g x m(-2)). Overall, the carbon accumulation ability of P. australis community (3212.96 g x m(-2)) was stronger than that of the S. alterniflora community (2730.42 g x m(-2)). Therefore, it is of significance to protect the P. australis community in terms of carbon sequestration at the salt marsh.
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Removal of PCP-Na from aqueous systems using monodispersed pompon-like magnetic nanoparticles as adsorbents.
Water Sci. Technol.
PUBLISHED: 12-21-2013
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Novel monodispersed pompon-like magnetite/chitosan (Fe3O4/CS) composite nanoparticles were synthesized by a solvothermal method and used as adsorbents for the removal of toxic sodium pentachlorophenate (PCP-Na) from aqueous media. The adsorption behavior of PCP-Na on Fe3O4/CS obeyed the Langmuir isotherm and fitted the pseudo-second-order kinetics model. Thermodynamic parameters showed that the adsorption process was exothermic and spontaneous. Moreover, the adsorption was strongly pH-dependent. The results of XPS, thermodynamics, pH-dependent and desorption studies suggested that electrostatic attraction, hydrogen bonding and ?-? interactions were all believed to play a role in PCP-Na adsorption on Fe3O4/CS. Having a saturation magnetization of 22.2 emu · g(-1), the Fe3O4/CS can be easily separated from water with magnets within 2 min. The adsorption equilibrium was achieved quite rapidly (within 30 min) and the maximum removal of PCP-Na (91.5%) was obtained at 25 °C and pH 6.5. The Fe3O4/CS investigated can be used to remove PCP-Na and other contaminants from wastewater.
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