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Find video protocols related to scientific articles indexed in Pubmed.
A Chinese Translation of the Inventory of Interpersonal Problems-Short Circumplex.
J Pers Assess
PUBLISHED: 11-04-2014
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The Inventory of Interpersonal Problems-Short Circumplex (IIP-SC) is a self-report measure of subjective distress linked to behavioral excesses and inhibitions in social relationships. The IIP-SC exhibits circumplex structure reflecting the underlying dimensions of dominance-submissiveness and warmth-coldness. We translated the IIP-SC into Mandarin Chinese using rigorous translation and back-translation methods with independent native speakers. University students in the People's Republic of China (N = 401) completed the translated IIP-SC and the Chinese Personality Assessment Inventory (CPAI-2), an omnibus measure of indigenous personality trait dimensions and symptoms of psychopathology. The circumplex structure of the Chinese IIP-SC was confirmed using principal components analysis, a randomization test for hypothesized order relations, and confirmatory circumplex analysis. The validity of the Chinese IIP-SC was evaluated by examining its associations with the CPAI-2 scales. Validity evidence for Chinese translation of the IIP-SC extends its use for clinical assessment to native Chinese speakers, although ongoing work to improve its reliability is needed.
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Functional MRI-guided microsurgery of intracranial arteriovenous malformations: study protocol for a randomised controlled trial.
BMJ Open
PUBLISHED: 10-25-2014
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Intracranial arteriovenous malformations (AVMs) are associated with high morbidity and mortality. Modern microsurgery has improved the results of surgical treatment of AVMs; however, the treatment of AVMs, particularly eloquently located AVMs, still carries a high risk. Functional MRI (fMRI) has been reported to be used for the preoperative evaluation of AVMs in small case series. The purpose is to identify the utility and efficacy of fMRI-guided microsurgery of AVMs in a large randomised controlled trial.
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[Danshensu delays the senescence of rat aortic endothelial cells via activation of SIRT1-SOD pathway].
Sheng Li Xue Bao
PUBLISHED: 10-22-2014
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The present study was aimed to investigate the effect of pretreatment with Danshensu (DSS) on rat aortic endothelial cells (RAECs) senescence and the underlying mechanisms. Cultured RAECs at fourth and twelfth passages were taken as young and old groups, respectively. DSS and DSS+nicotinamide (DSS+N) groups were incubated with DSS and DSS in combination with nicotinamide, an inhibitor of silent information regulator 1 (SIRT1), from the fourth to twelfth passage, respectively. The cell status of senescence was determined by the senescence-associated ?-galactosidase (SA ?-gal) staining, and 4,6-diamino-2-phenyl indole (DAPI) fluorescent dye was used to detect senescence associated heterochromatin foci (SAHF) formation; Thiobarbituric acid (TBA) and colorimetric methods were used to evaluate malondialdehyde (MDA) and H2O2 contents; Western blot was employed to analysis the expressions of xanthine oxidase (XOD), SIRT1 and superoxide dismutase 2 (SOD2) in the RAECs. The results showed that, in comparison with young group, the old group exhibited higher SA ?-gal positive and SAHF formation rates, as well as higher MDA and H2O2 levels (P < 0.05 or P < 0.01), whereas DSS pretreatment reduced SA ?-gal positive and SAHF formation rates, decreased MDA and H2O2 contents (P < 0.05 or P < 0.01). The protection of DSS was reversed by nicotinamide. Compared with the young group, the old group showed higher expression levels of XOD, but lower SIRT1 and SOD2 expression levels (P < 0.05 or P < 0.01). With the pretreatment of DSS, the expression of XOD was declined, and the expression levels of SIRT1 and SOD2 were elevated, while nicotinamide reversed the effects of DSS. These results suggest that DSS delays senescence of RAECs via up-regulation of SIRT1.
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Cytosolic carboxypeptidase CCP6 is required for megakaryopoiesis by modulating Mad2 polyglutamylation.
J. Exp. Med.
PUBLISHED: 10-20-2014
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Bone marrow progenitor cells develop into mature megakaryocytes (MKs) to produce platelets for hemostasis and other physiological functions. However, the molecular mechanisms underlying megakaryopoiesis are not completely defined. We show that cytosolic carboxypeptidase (CCP) 6 deficiency in mice causes enlarged spleens and increased platelet counts with underdeveloped MKs and dysfunctional platelets. The prominent phenotypes of CCP6 deficiency are different from those of CCP1-deficient mice. We found that CCP6 and tubulin tyrosine ligase-like family (TTLL) members TTLL4 and TTLL6 are highly expressed in MKs. We identify Mad2 (mitotic arrest deficient 2) as a novel substrate for CCP6 and not CCP1. Mad2 can be polyglutamylated by TTLL4 and TTLL6 to modulate the maturation of MKs. CCP6 deficiency causes hyperglutamylation of Mad2 to promote activation of Aurora B, leading to suppression of MK maturation. We reveal that Mad2 polyglutamylation plays a critical role in the regulation of megakaryopoiesis.
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[Scoring formula research and equivalence evaluation of mandarin quick speech-in-noise test materials in mainland China].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 10-18-2014
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To discuss the scoring formula and evaluate the lists equivalence of Mandarin Quick Speech-in-Noise (M-Quick SIN) test materials in mainland China, and for standardizing our research.
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Association Between CRP Gene Polymorphisms and the Risk of Preeclampsia in Han Chinese Women.
Genet Test Mol Biomarkers
PUBLISHED: 10-14-2014
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As an inflammatory marker, C-reactive protein (CRP) has elevated expression in preeclampsia (PE), which is implicated in the pathogenesis of PE, but there has been a lack of information on the possible association between genetic variants of CRP and PE. In this study, we aimed to assess the genetic association between CRP polymorphisms and the risk of PE in Han Chinese Women.
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Light-Scattering Detection below the Level of Single Fluorescent Molecules for High-Resolution Characterization of Functional Nanoparticles.
ACS Nano
PUBLISHED: 10-13-2014
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Ultrasensitive detection and characterization of single nanoparticles (<100 nm) is important in nanotechnology and life sciences. Direct measurement of the elastically scattered light from individual nanoparticles represents the simplest and the most direct method for particle detection. However, the sixth-power dependence of scattering intensity on particle size renders very small particles indistinguishable from the background. Adopting strategies for single-molecule fluorescence detection in a sheathed flow, here we report the development of high sensitivity flow cytometry (HSFCM) that achieves real-time light-scattering detection of single silica and gold nanoparticles as small as 24 and 7 nm in diameter, respectively. This unprecedented sensitivity enables high-resolution sizing of single nanoparticles directly based on their scattered intensity. With a resolution comparable to that of TEM and the ease and speed of flow cytometric analysis, HSFCM is particularly suitable for nanoparticle size distribution analysis of polydisperse/heterogeneous/mixed samples. Through concurrent fluorescence detection, simultaneous insights into the size and payload variations of engineered nanoparticles are demonstrated with two forms of clinical nanomedicine. By offering quantitative multiparameter analysis of single nanoparticles in liquid suspensions at a throughput of up to 10?000 particles per minute, HSFCM represents a major advance both in light-scattering detection technology and in nanoparticle characterization.
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Direct Determination of Multiple Ligand Interactions with the Extracellular Domain of the Calcium Sensing Receptor.
J. Biol. Chem.
PUBLISHED: 10-12-2014
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Numerous in vivo functional studies have indicated that the dimeric extracellular domain (ECD) of the CaSR plays a crucial role in regulating Ca2+ homeostasis by sensing Ca2+ and L-Phe. However, direct interaction of Ca2+ and Phe with the receptors ECD and the resultant impact on its structure and associated conformational changes have been hampered by the large size of the ECD, its high degree of glycosylation, and the lack of biophysical methods to monitor weak interactions in solution. In the present study, we purified the glycosylated extracellular domain of CaSR (ECD) (residues 20~612), containing either complex or high mannose N-glycan structures depending on the host cell line employed for recombinant expression. Both glycosylated forms of the CaSR ECD were purified as dimers and exhibit similar secondary structures with ~50% alpha-helix, ~20% beta-sheet content and a well buried Trp environment. Using various spectroscopic methods, we have shown that both protein variants bind Ca2+ with a Kd of 3.0~5.0 mM. The local conformational changes of the proteins induced by their interactions with Ca2+ were visualized by NMR with specific 15N Phe-labeled forms of the ECD. Saturation transfer difference (STD) NMR approaches demonstrated for the first time a direct interaction between the CaSR ECD and L-Phe. We further demonstrated that L-Phe increases the binding affinity of the CaSR ECD for Ca2+. Our findings provide new insights into the mechanisms by which Ca2+ and amino acids regulate the CaSR and may pave the way for exploration of the structural properties of CaSR and other members of family C of the GPCR superfamily.
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A new charging scheme in an emergency department observation unit under Beijing's basic medical insurance.
Chin. Med. J.
PUBLISHED: 10-01-2014
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The new medical insurance policy (JRSYF(2010) No.255) was released by the Beijing Municipal Government and became effective on January 1, 2011. Medical expenses incurred during a stay in an emergency department (ED) observation unit can be reimbursed as a hospital admission. The aim of this study was to evaluate the impact of a new charging scheme during stays in ED observation unit under Beijing's Basic Medical Insurance.
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Treatment of Radix Dipsaci extract prevents long bone loss induced by modeled microgravity in hindlimb unloading rats.
Pharm Biol
PUBLISHED: 09-23-2014
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Abstract Context: Radix Dipsaci is a kidney tonifying herbal medicine with a long history of safe use for treatment of bone fractures and joint diseases in China. Previous studies have shown that Radix Dipsaci extract (RDE) could prevent bone loss in ovariectomized rats. Objective: This study investigates the effect of RDE against bone loss induced by simulated microgravity. Materials and methods: A hindlimb unloading rat model was established to determine the effect of RDE on bone mineral density and bone microarchitecture. Twenty-four male Sprague-Dawley rats were divided into four groups (n?=?6 per group): control (CON), hindlimb unloading with vehicle (HLU), hindlimb unloading treated with alendronate (HLU-ALN, 2.0?mg/kg/d), and hindlimb unloading treated with RDE (HLU-RDE, 500?mg/kg/d). RDE or ALN was administrated orally for 4 weeks. Results: Treatment with RDE had a positive effect on mechanical strength, BMD, BMC, bone turnover markers, and the changes in urinary calcium and phosphorus excretion. MicroCT analysis showed that RDE significantly prevented the reduction of the bone volume fraction, connectivity density, trabecular number, thickness, tissue mineral density, and tissue mineral content as well as improved the trabecular separation and structure model index. Discussion and conclusion: RDE was demonstrated to prevent the loss of bone mass induced by HLU treatment, which suggests the potential application of RDE in the treatment of microgravity-induced bone loss.
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[Treatment of children with steroid-dependent nephrotic syndrome with rituximab].
Zhonghua Er Ke Za Zhi
PUBLISHED: 09-17-2014
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To investigate the effects of rituximab (RTX) in children with steroid-dependent nephrotic syndrome.
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[Research on the treatment of liver failure rats with transplantation of alginate microencapsulated hepatocytes in vivo based on poly-ornithine].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 09-16-2014
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This study aims to explore the effects of alginate-poly ornithine-alginate (A-PLO-A) and barium alginate-poly ornithine-alginate (B-PLO-A) microcapsules as cells carriers during implantation. Mice hepatocytes coated in A-PLO-A and B-PLO-A microcapsules were implanted into rats with acute liver failure caused by intraperitoneal injection of D-galactosamine. The rat survival rate, liver cell growth, proliferation and metabolism within the microcapsules were investigated, as well as its effect on the improvement of rat acute liver failure. The influence of A-PLO-A-free microcapsules, B-PLO-A-free microcapsules, isolated liver cells, A-PLO-A microcapsule-coated and B-PLO-A microcapsule-coated liver cells was studied. It was found that the chemical-free microcapsules showed no positive effect on the rats with liver failures, with a death rate of 100% in both groups 3 days after the implantation. The ALT, AST and ALB levels were all improved in the isolated liver cell group, the A-PLO-A microcapsule-coated and the B-PLO-A microcapsule-coated groups. The survival rate of both microcapsule-coated liver cell groups was significantly higher than that of the chemical-free microcapsule group and the isolated liver cells group. The microcapsules were retrieved after 4 weeks' implantation, which were observed to be smooth with no cells attaching to the surface. No apparent fibrosis was observed. This research demonstrated the physical stability and the biocompatibility of the PLO-based alginate microcapsules and therefore they could be used as liver cell carriers during implantation.
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WASH is required for the differentiation commitment of hematopoietic stem cells in a c-Myc-dependent manner.
J. Exp. Med.
PUBLISHED: 09-15-2014
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Hematopoiesis is fully dependent on hematopoietic stem cells (HSCs) that possess the capacity to self-renew and differentiate into all blood cell lineages. WASH, Wiskott-Aldrich syndrome protein (WASP) and SCAR homologue (WASH) is involved in endosomal sorting as an actin-nucleating protein. Here, we show that conditional WASH deletion in the hematopoietic system causes defective blood production of the host, leading to severe cytopenia and rapid anemia. WASH deficiency causes the accumulation of long-term (LT)-HSCs in bone marrow and perturbs their differentiation potential to mature blood lineages. Importantly, WASH is located in the nucleus of LT-HSCs and associates with the nucleosome remodeling factor (NURF) complex. WASH assists the NURF complex to the promoter of c-Myc gene through its VCA domain-dependent nuclear actin nucleation. WASH deletion suppresses the transcriptional activation of c-Myc gene and impairs the differentiation of LT-HSCs. WASH acts as an upstream regulator to modulate c-Myc transcription for hematopoietic regulation.
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The first flea with fully distended abdomen from the Early Cretaceous of China.
BMC Evol. Biol.
PUBLISHED: 08-27-2014
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Fleas, the most notorious insect ectoparasites of human, dogs, cats, birds, etc., have recently been traced to its basal and primitive ancestors during the Middle Jurassic. Compared with extant fleas, these large basal fleas have many different features. Although several fossil species with transitional morphologies filled the evolutionary blank, the early evolution of these ectoparasites is still poorly known.
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Modulation of DNA-polyamide interaction by ?-alanine substitutions: a study of positional effects on binding affinity, kinetics and thermodynamics.
Org. Biomol. Chem.
PUBLISHED: 08-21-2014
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Hairpin polyamides (PAs) are an important class of sequence-specific DNA minor groove binders, and frequently employ a flexible motif, ?-alanine (?), to reduce the molecular rigidity to maintain the DNA recognition register. To better understand the diverse effects that ? can have on DNA-PA binding affinity, selectivity, and especially kinetics, which have rarely been reported, we have initiated a detailed study for an eight-heterocyclic hairpin PA and its ? derivatives with their cognate and mutant sequences. With these derivatives, all internal pyrroles of the parent PA are systematically substituted with single or double ?s. A set of complementary experiments have been conducted to evaluate the molecular interactions in detail: UV-melting, biosensor-surface plasmon resonance, circular dichroism and isothermal titration calorimetry. The ? substitutions generally weaken the binding affinities of these PAs with cognate DNA, and have large and diverse influences on PA binding kinetics in a position- and number-dependent manner. The DNA base mutations have also shown positional effects on the binding of a single PA. Besides the ? substitutions, the monocationic Dp group [3-(dimethylamino)propylamine] in parent PA has been modified into a dicationic Ta group (3,3'-diamino-N-methyldipropylamine) to minimize the frequently observed PA aggregation with ITC experiments. The results clearly show that the Ta modification not only maintains the DNA binding mode and affinity of PA, but also significantly reduces PA aggregation and allows the complete thermodynamic signature of eight-ring hairpin PA to be determined for the first time. This combined set of results significantly extends our understanding of the energetic basis of specific DNA recognition by PAs.
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Autographa californica Multiple Nucleopolyhedrovirus orf132 Encodes a Nucleocapsid-Associated Protein Required for Budded-Virus and Multiply Enveloped Occlusion-Derived Virus Production.
J. Virol.
PUBLISHED: 08-20-2014
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Autographa californica multiple nucleopolyhedrovirus orf132 (named ac132) has homologs in all genome-sequenced group I nucleopolyhedroviruses. Its role in the viral replication cycle is unknown. In this study, ac132 was shown to express a protein of around 28 kDa, which was determined to be associated with the nucleocapsids of both occlusion-derived virus and budded virus. Confocal microscopy showed that AC132 protein appeared in central region of the nucleus as early as 12 h postinfection with the virus. It formed a ring zone at the periphery of the nucleus by 24 h postinfection. To investigate its role in virus replication, ac132 was deleted from the viral genome by using a bacmid system. In the Sf9 cell culture transfected by the ac132 knockout bacmid, infection was restricted to single cells, and the titer of infectious budded virus was reduced to an undetectable level. However, viral DNA replication and the expression of late genes vp39 and odv-e25 and a reporter gene under the control of the very late gene p10 promoter were unaffected. Electron microscopy showed that nucleocapsids, virions, and occlusion bodies were synthesized in the cells transfected by an ac132 knockout bacmid, but the formation of the virogenic stroma and occlusion bodies was delayed, the numbers of enveloped nucleocapsids were reduced, and the occlusion bodies contained mainly singly enveloped nucleocapsids. AC132 was found to interact with envelope protein ODV-E18 and the viral DNA-binding protein P6.9. The data from this study suggest that ac132 possibly plays an important role in the assembly and envelopment of nucleocapsids.
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The actin-bundling protein TRIOBP-4 and -5 promotes the motility of pancreatic cancer cells.
Cancer Lett.
PUBLISHED: 08-15-2014
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TRIOBP isoforms 4 and 5 (TRIOBP-4/-5) are an actin-bundling protein associated with hearing loss. Here, we showed that TRIOBP-4/-5 was up-regulated in human pancreatic carcinoma cells. Knockdown of TRIOBP-4/-5 led to a loss of filopodia and a decrease in cell motility. Confocal microscopy showed that re-expression of GFP-TRIOBP-4 or -5 restored the filopodial formation in TRIOBP-4/-5-deficient PANC-1 cells. Finally, TRIOBP-4/-5 was shown to be overexpressed in human pancreatic cancer tissues. These results demonstrate a novel role of TRIOBP-4/-5 that promotes the motility of pancreatic cancer cells via regulating actin cytoskeleton reorganization in the filopodia of the cells.
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Silencing B7-H1 enhances the anti-tumor effect of bladder cancer antigen-loaded dendritic cell vaccine in vitro.
Onco Targets Ther
PUBLISHED: 08-05-2014
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The aim of this study was to examine whether short hairpin RNA (shRNA) expressing lentiviral particles targeting B7-H1 infection could result in B7-H1 knockdown on dendritic cells (DCs) and to investigate whether B7-H1 silencing could augment the immune function of DCs and further elicit a more potent anti-tumor immune effect against bladder cancer cells in vitro.
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Correlation of IL-1F genetic polymorphisms with the risk of colorectal cancer among Chinese populations.
Tumour Biol.
PUBLISHED: 07-31-2014
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Inflammatory/immune cells have the power of infiltrating almost all human solid tumors and influencing all stages of carcinogenesis because of their stimulation of various cytokine subsets. This study aims to determine the correlation of single nucleotide polymorphisms in the IL-17F gene and the risk of colorectal cancer (CRC). One thousand patients diagnosed with CRC and a control group of 354 healthy controls were involved. Peripheral blood samples were collected. The PCR-RFLP method was used to detect the 7383A>G (rs2397084) and 7488T>C (rs763780) in the IL-17F gene. Statistical analyses were conducted with version 12.0 STATA statistical software. We found that the allele model suggested that patients carrying C allele were 1.67 times more likely to develop CRC than healthy controls (odds ratio (OR)?=?1.67, 95 % confidence interval (CI)?=?1.22-2.27, P?=?0.001). Similarly, the homozygous and dominant models also revealed that the minor IL-17F 7488C allele conferred an increased CRC risk compared to the major T allele among our study participants (CC vs. TT: OR?=?4.15, 95 % CI?=?1.26-13.36, P?=?0.011; TC+CC vs. TT: OR?=?1.46, 95 % CI?=?1.04-2.05, P?=?0.027). However, all genetic models indicated that the IL-17F 7383A>G (rs2397084) polymorphism was not associated with CRC risk (all P?>?0.05). The results of this study indicate that the 7488T>C (rs763780) in the IL-17F gene may be correlated with increased risk of CRC.
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Isolation and characterization of adipose-derived mesenchymal stem cells (ADSCs) from cattle.
Appl. Biochem. Biotechnol.
PUBLISHED: 07-28-2014
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Adipose-derived mesenchymal stem cells (ADSCs) were isolated from the adult adipose tissue of 2-year-old cattle, and then characterized by immunofluorescence and RT-PCR. We found that primary bADSCs could be expanded for 25 passages. Expression of ?-integrin, CD44, and CD73 was observed by immunofluorescence and RT-PCR. Passage 3 bADSCs were successfully induced to differentiate into osteoblasts and adipocytes. The results indicate the potential for multi-lineage differentiation of bADSCs that may represent an ideal candidate for cellular transplantation therapy.
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Predictive value of phosphorylated mammalian target of rapamycin for disease-free survival in breast cancer patients receiving neoadjuvant chemotherapy.
Oncol Lett
PUBLISHED: 07-25-2014
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The mammalian target of rapamycin (mTOR)/eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) pathway plays a critical role in cell growth, survival and angiogenesis, and has been demonstrated to correlate with human epidermal growth factor receptor 2 (HER2) status. Neoadjuvant chemotherapy (NAC), also known as preoperative therapy, is now well established in the treatment of inoperable locally advanced and inflammatory breast cancer. In vitro study has shown that mTOR inhibitors, together with cytotoxic agents, exhibit tumor cell killing activity. A number of non-randomized studies in HER2-positive trastuzumab-resistant metastatic breast cancer have revealed the antitumor activity of mTOR inhibitors when used together with standard chemotherapy plus trastuzumab. In the present study, the expression levels of phosphorylated (p)-mTOR and p-4E-BP1 were analyzed in breast cancer patients prior to and following NAC, to determine whether p-mTOR and p-4E-BP1 affect the response to NAC and the subsequent survival. Formalin-fixed, paraffin-embedded tissues representing matched pairs of core biopsy (pre-NAC) and surgical specimen (post-NAC) from 83 patients with invasive ductal carcinomas were collected. Immunohistochemistry was performed to evaluate the expression of p-mTOR and p-4E-BP1 using a semi-quantitative scoring system by two pathologists. It was found that the expression of p-mTOR and p-4E-BP1 was downregulated following NAC. The decrease in mTOR expression following NAC was found to positively correlate with HER2 expression and the reduction of tumor sizes. The high expression of p-mTOR and p-4E-BP1 in pre-NAC specimens was associated with poor disease-free survival (DFS). Furthermore, the high expression of p-mTOR in post-NAC specimens was associated with poor DFS, regardless of whether the expression was high or low in the pre-NAC specimens. In conclusion, NAC was found to decrease the expression levels of p-mTOR and p-4E-BP1. The p-mTOR expression post-NAC may potentially serve as a predictor for DFS. However, further study is required to clarify the mechanism and to evaluate the predictive value of the phosphatidylinositol 3-kinase/Akt/mTOR/4E-BP1 pathway in NAC.
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Validation and application of modeling algorithms for the design of molecularly imprinted polymers.
J Sep Sci
PUBLISHED: 07-25-2014
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In the study, four different semiempirical algorithms, modified neglect of diatomic overlap, a reparameterization of Austin Model 1, complete neglect of differential overlap and typed neglect of differential overlap, have been applied for the energy optimization of template, monomer, and template-monomer complexes of imprinted polymers. For phosmet-, estrone-, and metolcarb-imprinted polymers, the binding energies of template-monomer complexes were calculated and the docking configures were assessed in different molar ratio of template/monomer. It was found that two algorithms were not suitable for calculating the binding energy in template-monomers complex system. For the other algorithms, the obtained optimum molar ratio of template and monomers were consistent with the experimental results. Therefore, two algorithms have been selected and applied for the preparation of enrofloxacin-imprinted polymers. Meanwhile using a different molar ratio of template and monomer, we prepared imprinted polymers and nonimprinted polymers, and evaluated the adsorption to template. It was verified that the experimental results were in good agreement with the modeling results. As a result, the semiempirical algorithm had certain feasibility in designing the preparation of imprinted polymers.
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Evidence for existence of quorum sensing in a bioaugmented system by acylated homoserine lactone-dependent quorum quenching.
Environ Sci Pollut Res Int
PUBLISHED: 07-23-2014
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The introduction of a gene, strain, or microbial consortium into an indigenous bacterial population is known as bioaugmentation. This technique has been proposed as an effective strategy for accelerating and enhancing the removal of recalcitrant and toxic compounds during wastewater treatment. In this study, three types of reactors were used to test whether quorum sensing plays an important role in bioaugmented systems. Reverse transcriptase polymerase chain reaction showed that the inoculated strain, HF-1, successfully colonized in the bioaugmented reactor. Meanwhile, no HF-1 colonization was observed in the quorum-quenching and non-bioaugmented reactors. Removal of nicotine in the bioaugmented reactor was almost 100 %, and removal of total organic carbon (TOC) was higher than 50 %. However, less than 20 % of nicotine and 30 % of TOC was removed in quorum-quenching and non-bioaugmented reactors. Moreover, the release of acylated homoserine lactones reached the threshold for HF-1 biofilm formation in bioaugmented reactors but not in quorum-quenching or non-bioaugmented reactors. The addition of porcine kidney acylase I, a quenching reagent, to the quorum-quenching reactor hampered the colonization of HF-1. Together, these results demonstrate that quorum sensing plays an important role in HF-1 colonization of bioaugmented systems.
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B4GAT1 is the priming enzyme for the LARGE-dependent functional glycosylation of ?-dystroglycan.
Elife
PUBLISHED: 07-09-2014
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Recent studies demonstrated that mutations in B3GNT1, an enzyme proposed to be involved in poly-N-acetyllactosamine synthesis, were causal for congenital muscular dystrophy with hypoglycosylation of ?-dystroglycan (secondary dystroglycanopathies). Since defects in the O-mannosylation protein glycosylation pathway are primarily responsible for dystroglycanopathies and with no established O-mannose initiated structures containing a ?3 linked GlcNAc known, we biochemically interrogated this human enzyme. Here we report this enzyme is not a ?-1,3-N-acetylglucosaminyltransferase with catalytic activity towards ?-galactose but rather a ?-1,4-glucuronyltransferase, designated B4GAT1, towards both ?- and ?-anomers of xylose. The dual-activity LARGE enzyme is capable of extending products of B4GAT1 and we provide experimental evidence that B4GAT1 is the priming enzyme for LARGE. Our results further define the functional O-mannosylated glycan structure and indicate that B4GAT1 is involved in the initiation of the LARGE-dependent repeating disaccharide that is necessary for extracellular matrix protein binding to O-mannosylated ?-dystroglycan that is lacking in secondary dystroglycanopathies.
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A novel miniature dynamic microfluidic cell culture platform using electro-osmosis diode pumping.
Biomicrofluidics
PUBLISHED: 07-01-2014
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An electro-osmosis (EOS) diode pumping platform capable of culturing cells in fluidic cellular micro-environments particularly at low volume flow rates has been developed. Diode pumps have been shown to be a viable alternative to mechanically driven pumps. Typically electrokinetic micro-pumps were limited to low-concentration solutions (?10?mM). In our approach, surface mount diodes were embedded along the sidewalls of a microchannel to rectify externally applied alternating current into pulsed direct current power across the diodes in order to generate EOS flows. This approach has for the first time generated flows at ultra-low flow rates (from 2.0?nl/s to 12.3?nl/s) in aqueous solutions with concentrations greater than 100?mM. The range of flow was generated by changing the electric field strength applied to the diodes from 0.5?Vpp/cm to 10?Vpp/cm. Embedding an additional diode on the upper surface of the enclosed microchannel increased flow rates further. We characterized the diode pump-driven fluidics in terms of intensities and frequencies of electric inputs, pH values of solutions, and solution types. As part of this study, we found that the growth of A549 human lung cancer cells was positively affected in the microfluidic diode pumping system. Though the chemical reaction compromised the fluidic control overtime, the system could be maintained fully functional over a long time if the solution was changed every hour. In conclusion, the advantage of miniature size and ability to accurately control fluids at ultra-low volume flow rates can make this diode pumping system attractive to lab-on-a-chip applications and biomedical engineering in vitro studies.
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Neurons in the human amygdala selective for perceived emotion.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-30-2014
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The human amygdala plays a key role in recognizing facial emotions and neurons in the monkey and human amygdala respond to the emotional expression of faces. However, it remains unknown whether these responses are driven primarily by properties of the stimulus or by the perceptual judgments of the perceiver. We investigated these questions by recording from over 200 single neurons in the amygdalae of 7 neurosurgical patients with implanted depth electrodes. We presented degraded fear and happy faces and asked subjects to discriminate their emotion by button press. During trials where subjects responded correctly, we found neurons that distinguished fear vs. happy emotions as expressed by the displayed faces. During incorrect trials, these neurons indicated the patients' subjective judgment. Additional analysis revealed that, on average, all neuronal responses were modulated most by increases or decreases in response to happy faces, and driven predominantly by judgments about the eye region of the face stimuli. Following the same analyses, we showed that hippocampal neurons, unlike amygdala neurons, only encoded emotions but not subjective judgment. Our results suggest that the amygdala specifically encodes the subjective judgment of emotional faces, but that it plays less of a role in simply encoding aspects of the image array. The conscious percept of the emotion shown in a face may thus arise from interactions between the amygdala and its connections within a distributed cortical network, a scheme also consistent with the long response latencies observed in human amygdala recordings.
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[Performance-intensity function of short Mandarin monosyllabic word list for normal-hearing listeners].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 06-26-2014
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To analyze the short monosyllabic list of Mandarin speech test materials (MSTMs) which have been evaluated the equivalence of difficulty, and to establish the performance-intensity function (P-I function) for people with normal hearing as clinical reference of hearing recovery and individuals ability to perceive and process speech.
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Characterization of two UDP-Gal:GalNAc-diphosphate-lipid ?1,3-galactosyltransferases WbwC from Escherichia coli serotypes O104 and O5.
J. Bacteriol.
PUBLISHED: 06-23-2014
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Escherichia coli displays O antigens on the outer membrane that play an important role in bacterial interactions with the environment. The O antigens of enterohemorrhagic E. coli O104 and O5 contain a Gal?1-3GalNAc disaccharide at the reducing end of the repeating unit. Several other O antigens contain this disaccharide, which is identical to the mammalian O-glycan core 1 or the cancer-associated Thomsen-Friedenreich (TF) antigen. We identified the wbwC genes responsible for the synthesis of the disaccharide in E. coli serotypes O104 and O5. To functionally characterize WbwC, an acceptor substrate analog, GalNAc?-diphosphate-phenylundecyl, was synthesized. WbwC reaction products were isolated by high-pressure liquid chromatography and analyzed by mass spectrometry, nuclear magnetic resonance, galactosidase and O-glycanase digestion, and anti-TF antibody. The results clearly showed that the Gal?1-3GalNAc? linkage was synthesized, confirming WbwCECO104 and WbwCECO5 as UDP-Gal:GalNAc?-diphosphate-lipid ?1,3-Gal-transferases. Sequence analysis revealed a conserved DxDD motif, and mutagenesis showed the importance of these Asp residues in catalysis. The purified enzymes require divalent cations (Mn(2+)) for activity and are specific for UDP-Gal and GalNAc-diphosphate lipid substrates. WbwC was inhibited by bis-imidazolium salts having aliphatic chains of 18 to 22 carbons. This work will help to elucidate mechanisms of polysaccharide synthesis in pathogenic bacteria and provide technology for vaccine synthesis.
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Mechanistic heterogeneity in site recognition by the structurally homologous DNA-binding domains of the ETS family transcription factors Ets-1 and PU.1.
J. Biol. Chem.
PUBLISHED: 06-21-2014
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ETS family transcription factors regulate diverse genes through binding at cognate DNA sites that overlap substantially in sequence. The DNA-binding domains of ETS proteins (ETS domains) are highly conserved structurally yet share limited amino acid homology. To define the mechanistic implications of sequence diversity within the ETS family, we characterized the thermodynamics and kinetics of DNA site recognition by the ETS domains of Ets-1 and PU.1, which represent the extremes in amino acid divergence among ETS proteins. Even though the two ETS domains bind their optimal sites with similar affinities under physiologic conditions, their nature of site recognition differs strikingly in terms of the role of hydration and counter ion release. The data suggest two distinct mechanisms wherein Ets-1 follows a "dry" mechanism that rapidly parses sites through electrostatic interactions and direct protein-DNA contacts, whereas PU.1 utilizes hydration to interrogate sequence-specific sites and form a long-lived complex relative to the Ets-1 counterpart. The kinetic persistence of the high affinity PU.1 · DNA complex may be relevant to an emerging role of PU.1, but not Ets-1, as a pioneer transcription factor in vivo. In addition, PU.1 activity is critical to the development and function of macrophages and lymphocytes, which present osmotically variable environments, and hydration-dependent specificity may represent an important regulatory mechanism in vivo, a hypothesis that finds support in gene expression profiles of primary murine macrophages.
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Functional characterization of Cinnamoyl-CoA Reductase (CCR) in birch (Betula platyphylla × Betula pendula) through overexpression and suppression analysis.
Physiol Plant
PUBLISHED: 06-20-2014
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We cloned a Cinnamoyl-CoA Reductase gene (BpCCR1) from an apical meristem and first internode of Betula platyphylla and characterized its functions in lignin biosynthesis, wood formation, and tree growth through transgenic approaches. We generated overexpression and suppression transgenic lines and analyzed them in comparison with the wild-type in terms of lignin content, anatomical characteristics, height and biomass. We found that BpCCR1 overexpression could increase lignin content up to 14.6%, and its underexpression decreased lignin content by 6.3%. Surprisingly, modification of BpCCR1 expression led to conspicuous changes in wood characteristics, including xylem vessel number and arrangement, and secondary wall thickness. The growth of transgenic trees in terms of height was also significantly influenced by the modification of BpCCR1 genes. We discussed the functions of BpCCR1 in the context of a phylogenetic tree built with CCR genes from multiple species.
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Prussian blue mediated amplification combined with signal enhancement of ordered mesoporous carbon for ultrasensitive and specific quantification of metolcarb by a three-dimensional molecularly imprinted electrochemical sensor.
Biosens Bioelectron
PUBLISHED: 06-18-2014
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In this work, we presented a three-dimensional (3D) molecularly imprinted electrochemical sensor (MIECS) with novel strategy for ultrasensitive and specific quantification of metolcarb based on prussian blue (PB) mediated amplification combined with signal enhancement of ordered mesoporous carbon. The molecularly imprinted polymers were synthesized by electrochemically induced redox polymerization of para aminobenzoic acid (p-ABA) in the presence of template metolcarb. Ordered mesoporous carbon material (CMK-3) was introduced to enhance the electrochemical response by improving the structure of the modified electrodes and facilitating charge transfer processes of PB which was used as an inherent electrochemical active probe. The modification process for the working electrodes of the MIECS was characterized by scanning electron microscope (SEM) and cyclic voltammetry (CV), and several important parameters controlling the performance of the MIECS were investigated and optimized in detail. The MIECS with 3D structure had the advantages of ease of preparation, high porous surface structure, speedy response, ultrasensitivity, selectivity, reliable stability, good reproducibility and repeatability. Under the optimal conditions, the MIECS offered an excellent current response for metolcarb in the linear response range of 5.0×10(-10)-1.0×10(-4)molL(-1) and the limit of detection (LOD) was calculated to be 9.3×10(-11)molL(-1) (S/N=3). The proposed MIECS has been successfully applied for the determination of metolcarb in real samples with satisfactory recoveries. Furthermore, the construction route of this ultrasensitive 3D MIECS may provide a guideline for the determination of non-electroactive analytes in environmental control and food safety.
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[Effects of temporal fine structure stimulation on Mandarin identification in cochlear implant users].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 06-17-2014
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To assess the contribution of the temporal fine structure cues on speech recognition, especially tone perception of cochlear implant users whose native language is Mandarin Chinese.
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Site-specific glycan microheterogeneity of inter-alpha-trypsin inhibitor heavy chain H4.
J. Proteome Res.
PUBLISHED: 06-12-2014
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Inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4) is a 120 kDa acute-phase glycoprotein produced primarily in the liver, secreted into the blood, and identified in serum. ITIH4 is involved in liver development and stabilization of the extracellular matrix (ECM), and its expression is altered in liver disease. In this study, we aimed to characterize glycosylation of recombinant and serum-derived ITIH4 using analytical mass spectrometry. Recombinant ITIH4 was analyzed to optimize glycopeptide analyses, followed by serum-derived ITIH4. First, we confirmed that the four ITIH4 N-X-S/T sequons (N81, N207, N517, and N577) were glycosylated by treating ITIH4 tryptic/GluC glycopeptides with PNGaseF in the presence of (18)O water. Next, we performed glycosidase-assisted LC-MS/MS analysis of ITIH4 trypsin-GluC glycopeptides enriched via hydrophilic interaction liquid chromatography to characterize ITIH4 N-glycoforms. While microheterogeneity of N-glycoforms differed between ITIH4 protein expressed in HEK293 cells and protein isolated from serum, occupancy of N-glycosylation sites did not differ. A fifth N-glycosylation site was discovered at N274 with the rare nonconsensus NVV motif. Site N274 contained high-mannose N-linked glycans in both serum and recombinant ITIH4. We also identified isoform-specific ITIH4 O-glycoforms and documented that utilization of O-glycosylation sites on ITIH4 differed between the cell line and serum.
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Facile preparation of organic-inorganic hybrid polymeric ionic liquid monolithic column with a one-pot process for protein separation in capillary electrochromatography.
Anal Bioanal Chem
PUBLISHED: 06-07-2014
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An organic-inorganic hybrid monolithic column based on 1-vinyl-3-dodecylimidazolium bromide (VC12Im(+)Br(-)) has been prepared in a single step by combining radical copolymerization with a non-hydrolytic sol-gel (NHSG) process. The NHSG process was significantly shortened to 6 h by using formic acid as catalyst. For comparison, we also prepared polymeric ionic liquid (PIL) monolithic columns by hydrolytic sol-gel and organic polymeric process, respectively. The resulting monolithic columns were characterized by Fourier transform infrared spectra, scanning electron microscopy, and Brunauer-Emmett-Teller. Under the capillary electrochromatography mode, these columns were applied to separate alkylbenzenes, anilines, and proteins, respectively. The results indicated that the NHSG-based hybrid PIL monolithic column exhibited the highest column efficiency among the three types of columns; organic solvent, commonly required by the traditional columns to achieve satisfactory separation efficiency for proteins, was absent in the NHSG-based hybrid PIL monolithic column because of the biocompatibility of the VC12Im(+)Br(-), which was beneficial to analysis of protein containing samples. In order to demonstrate its application potential, the developed NHSG-based hybrid PIL monolithic column was also employed to separate egg white sample.
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Development and application of quartz crystal microbalance sensor based on novel molecularly imprinted sol-gel polymer for rapid detection of histamine in foods.
J. Agric. Food Chem.
PUBLISHED: 05-29-2014
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To rapidly detect histamine (HA) in foods, a novel material for HA-specific recognition was synthesized by a sol-gel process and coated on a quartz crystal microbalance (QCM) sensor. The Scatchard model was used to evaluate the adsorption performance of the material; high affinity for HA was demonstrated. Based on QCM frequency change, the sensor exhibited linear behavior for HA concentrations of 0.11 × 10(-2) to 4.45 × 10(-2) mg L(-1), a detection limit of 7.49 × 10(-4) mg kg(-1) (S/N = 3), high selectivity for HA (selectivity coefficient >4) compared with structural analogues, good reproducibility, and long-term stability. The sensor was used to determine the concentration of HA in spiked fish products; the recovery values were satisfactory (93.2-100.4%) and compared well with those obtained by high-performance liquid chromatography (correlation coefficient, r(2) = 0.9965).
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DNA Binding Polyamides and the Importance of DNA Recognition in their use as Gene-Specific and Antiviral Agents.
Med Chem (Los Angeles)
PUBLISHED: 05-20-2014
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There is a long history for the bioorganic and biomedical use of N-methyl-pyrrole-derived polyamides (PAs) that are higher homologs of natural products such as distamycin A and netropsin. This work has been pursued by many groups, with the Dervan and Sugiyama groups responsible for many breakthroughs. We have studied PAs since about 1999, partly in industry and partly in academia. Early in this program, we reported methods to control cellular uptake of polyamides in cancer cell lines and other cells likely to have multidrug resistance efflux pumps induced. We went on to discover antiviral polyamides active against HPV31, where SAR showed that a minimum binding size of about 10 bp of DNA was necessary for activity. Subsequently we discovered polyamides active against two additional high-risk HPVs, HPV16 and 18, a subset of which showed broad spectrum activity against HPV16, 18 and 31. Aspects of our results presented here are incompatible with reported DNA recognition rules. For example, molecules with the same cognate DNA recognition properties varied from active to inactive against HPVs. We have since pursued the mechanism of action of antiviral polyamides, and polyamides in general, with collaborators at NanoVir, the University of Missouri-St. Louis, and Georgia State University. We describe dramatic consequences of ?-alanine positioning even in relatively small, 8-ring polyamides; these results contrast sharply with prior reports. This paper was originally presented by JKB as a Keynote Lecture in the 2(nd) International Conference on Medicinal Chemistry and Computer Aided Drug Design Conference in Las Vegas, NV, October 2013.
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Effects of antioxidants of bamboo leaves and flavonoids on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) formation in chemical model systems.
J. Agric. Food Chem.
PUBLISHED: 05-13-2014
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The inhibitory effects of antioxidants of bamboo leaves (AOB) and flavonoids against 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) formation were investigated in creatinine and phenylalanine model systems. AOB and the tested flavonoids (orientin, homoorientin, vitexin, isovitex, apigenin, luteolin, isorhamnetin, fisetin, and hesperetin) had significant dose-dependent inhibition effects on PhIP formation with different IC50 values. The superoxide anion (O2(•-)) scavenging activities of these nine flavonoids were evaluated using the pyrogallol autoxidation system. The EC50 values of compounds that showed antioxidant activity were found to correlate well (R(2) = 0.8003) with the corresponding IC50 values representing their inhibition of PhIP formation. It was assumed that the inhibitory effects of flavonoids on PhIP formation were probably achieved by scavenging free radicals generated in the reaction system. These findings provide valuable information for the development of effective strategies to minimize heterocyclic amine content in thermally processed food.
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Preferential attention to animals and people is independent of the amygdala.
Soc Cogn Affect Neurosci
PUBLISHED: 05-01-2014
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The amygdala is thought to play a critical role in detecting salient stimuli. Several studies have taken ecological approaches to investigating such saliency, and argue for domain-specific effects for processing certain natural stimulus categories, in particular faces and animals. Linking this to the amygdala, neurons in the human amygdala have been found to respond strongly to faces and also to animals. However, the amygdala's necessary role for such category-specific effects at the behavioral level remains untested. Here we tested four rare patients with bilateral amygdala lesions on an established change-detection protocol. Consistent with prior published studies, healthy controls showed reliably faster and more accurate detection of people and animals, as compared with artifacts and plants. So did all four amygdala patients: there were no differences in phenomenal change blindness, in behavioral reaction time to detect changes or in eye-tracking measures. The findings provide decisive evidence against a critical participation of the amygdala in rapid initial processing of attention to animate stimuli, suggesting that the necessary neural substrates for this phenomenon arise either in other subcortical structures (such as the pulvinar) or within the cortex itself.
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Effects of Chinese Medicine Shen-Fu Injection () on the expression of inflammatory cytokines and complements during post-resuscitation immune dysfunction in a porcine model.
Chin J Integr Med
PUBLISHED: 04-30-2014
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To investigate the action of Shen-Fu Injection (, SFI) in regulating the expression of the serum complements and inflammatory cytokines synthesized and released in response to the stress of global ischemia accompanying cardiac arrest (CA) and resuscitation.
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Association between socioeconomic status (SES), mental health and need for long-term care (NLTC)-A Longitudinal Study among the Japanese Elderly.
Arch Gerontol Geriatr
PUBLISHED: 04-24-2014
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This study was carried out to explore the relationship between the SES, mental health and the NLTC of the Japanese elderly, with the aim of providing useful information to lower the NLTC. A longitudinal survey was carried out in Tama City, Tokyo in 2001 and 2004. Data were collected from the urban-dwelling older adults, aged 65 years old and above, through self-reported questionnaires, which was participated by 7905 respondents (47.6% male and 52.4% female). Chi-square test, Kendall tau-b correlation analysis and structural equation modeling (SEM) were used to identify the association between SES, mental health and NLTC. The results of the SEM analysis indicated that mental health would exert a negative effect on NLTC for both the elderly men and the elderly women, while the effect was stronger for the elderly women; SES was significantly and negatively associated to NLTC, both for the elderly men and elderly women; a significant and positive relationship was observed between SES and mental health for both genders, but slightly stronger for the elderly men. These findings have implications for targeting the interventions that are aimed to delaying the NLTC and the financing of LTC system.
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Rapid and efficient assembly of transcription activator-like effector genes by USER cloning.
J Genet Genomics
PUBLISHED: 04-10-2014
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Transcription activator-like effectors (TALEs) that were related to bacteria immune system have lately been employed in a promising approach of precise gene targeting. Because of the repetitive characteristics of TALEs, existing TALE assembly methods are either very complicated, time-consuming, or too tricky to be handled in common labs. Here, we reported a rapid, efficient and easy method for TALE assembly. This method takes advantage of uracil-specific excision reagent (USER), an enzyme that can cleave DNA constructs and create long, unique single-strand DNA overhangs. Upon USER treatment, the overhangs on each individual TALE repeat unit can be rejoined hierarchically to form pentamers in a ligation-independent manner. Eventually, three pentamers are assembled into a full TALE construct by Golden Gate cloning. TALE nucleases (TALENs) generated with this method exhibit high genome-editing activity in human cells such as HEK293FT cells. Using this method, we have successfully synthesized three TALEN pairs targeting endogenous Tet1 locus, and proved that all can specifically target Tet1 gene, though in various degree. Comparing to other methods of TALEN assembly, this one is much less labor intensive and fairly faster, and positive clones can be obtained at high efficiency within only two days. We thus contribute to an easier approach for effective TALENs synthesis, which may highly facilitate the wide application of TALEN technology in genome editing, especially for human cells that require precise targeting.
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Protein imprinted ionic liquid polymer on the surface of multiwall carbon nanotubes with high binding capacity for lysozyme.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 04-08-2014
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In this research, ionic liquid as functional monomer to prepare molecularly imprinted polymers for protein recognition was for the first time demonstrated, in which, 1-vinyl-3-butylimidazolium chloride was selected as functional monomer, acrylamide as co-functional monomer and lysozyme (Lyz) as template protein to synthesize imprinted polymers on the surface of multiwall carbon nanotubes in aqueous medium. The results indicated that ionic liquid was helpful to improve binding capacity of imprinted polymers, which had a maximum binding capacity of 763.36 mg/g in the optimum adsorption conditions. The prepared imprinted polymers had a fast adsorption rate and a much higher adsorption capacity than the corresponding non-imprinted polymers, with the difference in adsorption capacity up to 258.31 mg/g. The obtained polymer was evaluated by Lyz, bovine serum albumin (BSA), bovine hemoglobin (BHb), equine myoglobin (MB) and cytochrome c (Cyt c). The selectivity factor (?) for Lyz/BSA, Lyz/Mb, Lyz/BHb, and Lyz/Cyt c were 7.17, 2.12, 1.76 and 1.57, respectively, indicating the imprinted polymers had a good selectivity. Easy preparation of the imprinted polymers as well as high ability and selectivity to adsorb template proteins makes this polymer attractive and broadly applicable in biomacromolecular separation, biotechnology and sensors.
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Addition of bevacizumab enhances antitumor activity of erlotinib against non-small cell lung cancer xenografts depending on VEGF expression.
Cancer Chemother. Pharmacol.
PUBLISHED: 04-07-2014
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Erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), and bevacizumab, an anti-vascular endothelial growth factor (VEGF) agent, are promising therapies for advanced non-small cell lung cancer (NSCLC). Our study was aimed to determine whether there were conditions under which the addition of bevacizumab would enhance the antitumor activity of erlotinib against NSCLC tumors in vitro and in vivo.
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Autism spectrum disorder, but not amygdala lesions, impairs social attention in visual search.
Neuropsychologia
PUBLISHED: 04-07-2014
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People with autism spectrum disorders (ASD) have pervasive impairments in social interactions, a diagnostic component that may have its roots in atypical social motivation and attention. One of the brain structures implicated in the social abnormalities seen in ASD is the amygdala. To further characterize the impairment of people with ASD in social attention, and to explore the possible role of the amygdala, we employed a series of visual search tasks with both social (faces and people with different postures, emotions, ages, and genders) and non-social stimuli (e.g., electronics, food, and utensils). We first conducted trial-wise analyses of fixation properties and elucidated visual search mechanisms. We found that an attentional mechanism of initial orientation could explain the detection advantage of non-social targets. We then zoomed into fixation-wise analyses. We defined target-relevant effects as the difference in the percentage of fixations that fell on target-congruent vs. target-incongruent items in the array. In Experiment 1, we tested 8 high-functioning adults with ASD, 3 adults with focal bilateral amygdala lesions, and 19 controls. Controls rapidly oriented to target-congruent items and showed a strong and sustained preference for fixating them. Strikingly, people with ASD oriented significantly less and more slowly to target-congruent items, an attentional deficit especially with social targets. By contrast, patients with amygdala lesions performed indistinguishably from controls. In Experiment 2, we recruited a different sample of 13 people with ASD and 8 healthy controls, and tested them on the same search arrays but with all array items equalized for low-level saliency. The results replicated those of Experiment 1. In Experiment 3, we recruited 13 people with ASD, 8 healthy controls, 3 amygdala lesion patients and another group of 11 controls and tested them on a simpler array. Here our group effect for ASD strongly diminished and all four subject groups showed similar target-relevant effects. These findings argue for an attentional deficit in ASD that is disproportionate for social stimuli, cannot be explained by low-level visual properties of the stimuli, and is more severe with high-load top-down task demands. Furthermore, this deficit appears to be independent of the amygdala, and not evident from general social bias independent of the target-directed search.
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A comparative study of annealing of waxy, normal and high-amylose maize starches: the role of amylose molecules.
Food Chem
PUBLISHED: 04-05-2014
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The effect of annealing on starch structure and functionality of three maize starches (waxy, normal and high-amylose) was investigated, with the aim of understanding the role of amylose molecules during starch annealing. Amylose content, granular morphology and crystallinity of maize starches were little affected by annealing treatment. Annealing treatment did not alter the swelling power of waxy maize starch, but reduced the swelling power of normal and high-amylose maize starches. The thermal transition temperatures were increased, and the temperature range was decreased, but the enthalpy change was not affected greatly. The pasting viscosities of normal and waxy maize starches were decreased significantly, with the pasting temperature being little affected. The in vitro digestibility of three maize starches was not affected significantly by annealing treatment. Our results demonstrated that amylose molecules play an important role in the structural reorganization of starch granules during annealing treatment.
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Socioeconomic status, comorbidity, activity limitation, and healthy life expectancy in older men and women: a 6-year follow-up study in Japan.
J Appl Gerontol
PUBLISHED: 03-22-2014
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This study aimed to explore the structural contributions of socioeconomic status (SES), comorbidity, and activity limitation to the healthy life expectancy (HALE) of Japanese suburban elderly. A questionnaire survey was distributed to all residents aged 65 years and older in Tama City, Tokyo, in 2001; a follow-up study was conducted in 2004; and individual vital status data from the municipal residents' registry were tracked until 2007. In all, 7,905 respondents were included for analysis. Data analysis was performed by structural equation modeling (SEM). The data were well fit by the models, and HALE was found to be well explained by SES, comorbidity, and activity limitation (R (2) = .59 for men and R (2) = .71 for women). In conclusion, elderly people with higher SES were more likely to live longer with good self-rated health, via living with less chronic diseases and better performance in daily living activities, especially for elderly women.
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Effect of RFRP-3 on reproduction is sex- and developmental status-dependent in the striped hamster (Cricetulus barabensis).
Gene
PUBLISHED: 03-17-2014
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RFamide-related peptides (RFRPs) are orthologous to gonadotropin-inhibitory hormone (GnIH) inhibiting gonadotropin release. There are only two RFRP sequences (RFRP-1 and RFRP-3) encoded in rodents. RFRP-3, which was considered as a hypothetical inhibitor on GnRH, shows a stimulatory effect on the male Syrian and male Siberian hamster in short days. As a dominant rodent pest in northern China farmland, the striped hamster (Cricetulus barabensis) has higher reproductive activities and could act as a model to study the mechanism of reproduction. However, the effect of RFRP-3 on the reproductive activity for the striped hamster is less understood. In the study, we cloned 643 bp RFRP cDNA from the striped hamster hypothalamus, which contained an ORF of 570 bp encoding two RFamide-related peptide (RFRP) sequences: SPAPANKVPHSAANLPLRF-NH2 (C. barabensis RFRP-1) and TLSRVPSLPQRF-NH2 (C. barabensis RFRP-3). We also investigated the expression variation of RFRP mRNA and GnRH mRNA in the hypothalamus from hamsters with different developmental statuses (7-week-, 13-week- and 1.5-year-olds) using FQ-PCR, in which the 13-week-old female individuals were in estrous. The striped hamsters that are 7 weeks and 1.5 years old are non-breeding individuals, and those that are 13-week hamsters have breeding phenomena. The highest hypothalamus RFRP mRNA level was found in breeding males as compared to non-breeding males. Conversely, the lowest RFRP mRNA level in the hypothalamus was observed in breeding females, with no significant level when the breeding females were compared to the 7-week-old individuals. Additionally, the investigation of GnRH expression level showed a declining expression trend across the developmental stages (7-week-, 13-week- and 1.5-year-olds) in both sexes. Significant negative and positive relationships were detected in the 13-week estrous female (r=-0.997, P=0.035) and the 13-week male (r=0.998, P=0.029) striped hamsters respectively, which suggest that RFRP-3 has inhibitory and stimulatory effects on female and male adults respectively. Our results suggest that the effects of RFRP-3 on reproduction are sex- and developmental status-dependent in the striped hamster.
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RNF2 is recruited by WASH to ubiquitinate AMBRA1 leading to downregulation of autophagy.
Cell Res.
PUBLISHED: 03-12-2014
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WASH (Wiskott-Aldrich syndrome protein (WASP) and SCAR homolog) was identified to function in endosomal sorting via Arp2/3 activation. We previously demonstrated that WASH is a new interactor of BECN1 and present in the BECN1-PIK3C3 complex with AMBRA1. The AMBRA1-DDB1-CUL4A complex is an E3 ligase for K63-linked ubiquitination of BECN1, which is required for starvation-induced autophagy. WASH suppresses autophagy by inhibition of BECN1 ubiquitination. However, how AMBRA1 is regulated during autophagy remains elusive. Here, we found that RNF2 associates with AMBRA1 to act as an E3 ligase to ubiquitinate AMBRA1 via K48 linkage. RNF2 mediates ubiquitination of AMBRA1 at lysine 45. Notably, RNF2 deficiency enhances autophagy induction. Upon autophagy induction, RNF2 potentiates AMBRA1 degradation with the help of WASH. WASH deficiency impairs the association of RNF2 with AMBRA1 to impede AMBRA1 degradation. Our findings reveal another novel layer of regulation of autophagy through WASH recruitment of RNF2 for AMBRA1 degradation leading to downregulation of autophagy.
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Embolization of renal artery pseudoaneurysm following laparoscopic partial nephrectomy for central renal tumor: A report of two cases.
Oncol Lett
PUBLISHED: 02-04-2014
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Laparoscopic partial nephrectomy has recently emerged as a minimally invasive treatment for small- to moderate-sized renal tumors. Renal artery pseudoaneurysms (RAPs) have been well-reported in patients with renal trauma or who have undergone percutaneous urological procedures, including biopsy, nephrostomy and percutaneous nephroureterolithotomy. However, RAP following laparoscopic partial nephrectomy for central renal tumor is a rare but serious, potentially life-threatening complication. In total, two patients underwent laparoscopic partial nephrectomy at The First Affiliated Hospital of Zhejiang University School of Medicine (Hangzhou, China) for central renal tumors that had developed gross hematuria several weeks following the surgical procedures. The formation of RAPs was confirmed by contrast-enhanced computed tomography scans. Superselective embolizations of the renal artery branches were successfully performed to treat these two patients. In the current report, the etiology, diagnosis and management of RAPs are discussed.
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Association between diabetes mellitus with metabolic syndrome and diabetic microangiopathy.
Exp Ther Med
PUBLISHED: 01-12-2014
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The aim of this study was to investigate the association between diabetes mellitus (DM), mainly type II, with metabolic syndrome (MS) and diabetic nephropathy (DN)/diabetic retinopathy (DR). Based on the analysis of the prevalence of MS, patients with DM were divided into MS and non-MS groups according to the presence or absence of MS. The correlation between DN, DR and certain factors, including gender, age, disease duration and the presence or absence of a family history of MS, were analyzed. The prevalence of MS among the patients with DM was 62.50%. The prevalence of DN was 55.33% in the MS group and that of DR was 26.00%. DN was positively correlated with age, gender, blood pressure, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and blood uric acid. DR was positively correlated with traceable disease duration and LDL-C. In conclusion, DM occurred more frequently in concurrence with MS than without MS, and the prevalence of DN/DR in the MS group was higher than that in the non-MS group. Age, gender, blood pressure, TG, LDL-C and blood uric acid were risk factors for DN and the traceable disease duration and LDL-C were risk factors for DR.
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Retroperitoneal Laparoscopic Management of Ureteropelvic Junction Obstruction in Patients With Horseshoe Kidney.
Urology
PUBLISHED: 01-11-2014
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To report our experience with retroperitoneal laparoscopic pyeloplasty for the management of ureteropelvic junction (UPJ) obstruction in patients with horseshoe kidneys (HSKs).
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The relationship between frontal lobe lesions, course of post-stroke depression, and 1-year prognosis in patients with first-ever ischemic stroke.
PLoS ONE
PUBLISHED: 01-01-2014
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Most studies on post-stroke depression (PSD) have focused on a certain time point after stroke instead of the time course of PSD. The aim of this study was to determine the relationship between frontal lobe lesions, course of PSD over a year following the stroke onset, and the 1-year prognosis in patients with first-ever ischemic stroke.
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eIF2? phosphorylation bypasses premature senescence caused by oxidative stress and pro-oxidant antitumor therapies.
Aging (Albany NY)
PUBLISHED: 12-17-2013
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Eukaryotic cells respond to various forms of stress by blocking mRNA translation initiation via the phosphorylation of the alpha (?) subunit of eIF2 at serine 51 (S51) (eIF?P). An important role of eIF2?P is the regulation of redox homeostasis and adaptation of cells to oxidative stress. Herein, we demonstrate that eIF2?P guards cells from intracellular reactive oxygen species (ROS) via the inhibition of senescence. Specifically, genetic inactivation of either eIF2?P or eIF2? kinase PERK in primary mouse or human fibroblasts leads to proliferative defects associated with increased DNA damage, G2/M accumulation and induction of premature senescence. Impaired proliferation of either PERK or eIF2?P-deficient primary cells is caused by increased ROS and restored by anti-oxidant treatment. Contrary to primary cells, impaired eIF2?P in immortalized mouse fibroblasts or human tumor cells provides tolerance to elevated intracellular ROS levels. However, eIF2?P-deficient human tumor cells are highly susceptible to extrinsic ROS generated by the pro-oxidant drug doxorubicin by undergoing premature senescence. Our work demonstrates that eIF2?P determines cell destiny through its capacity to control senescence in response to oxidative stress. Also, inhibition of eIF2?P may be a suitable means to increase the anti-tumor effects of pro-oxidant drugs through the induction of senescence.
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Hypoxia shifts activity of neuropeptide Y in Ewing sarcoma from growth-inhibitory to growth-promoting effects.
Oncotarget
PUBLISHED: 12-10-2013
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Ewing sarcoma (ES) is an aggressive malignancy driven by an oncogenic fusion protein, EWS-FLI1. Neuropeptide Y (NPY), and two of its receptors, Y1R and Y5R are up-regulated by EWS-FLI1 and abundantly expressed in ES cells. Paradoxically, NPY acting via Y1R and Y5R stimulates ES cell death. Here, we demonstrate that these growth-inhibitory actions of NPY are counteracted by hypoxia, which converts the peptide to a growth-promoting factor. In ES cells, hypoxia induces another NPY receptor, Y2R, and increases expression of dipeptidyl peptidase IV (DPPIV), an enzyme that cleaves NPY to a shorter form, NPY3-36. This truncated peptide no longer binds to Y1R and, therefore, does not stimulate ES cell death. Instead, NPY3-36 acts as a selective Y2R/Y5R agonist. The hypoxia-induced increase in DPPIV activity is most evident in a population of ES cells with high aldehyde dehydrogenase (ALDH) activity, rich in cancer stem cells (CSCs). Consequently, NPY, acting via Y2R/Y5Rs, preferentially stimulates proliferation and migration of hypoxic ALDHhigh cells. Hypoxia also enhances the angiogenic potential of ES by inducing Y2Rs in endothelial cells and increasing the release of its ligand, NPY3-36, from ES cells. In summary, hypoxia acts as a molecular switch shifting NPY activity away from Y1R/Y5R-mediated cell death and activating the Y2R/Y5R/DPPIV/NPY3-36 axis, which stimulates ES CSCs and promotes angiogenesis. Hypoxia-driven actions of the peptide such as these may contribute to ES progression. Due to the receptor-specific and multifaceted nature of NPY actions, these findings may inform novel therapeutic approaches to ES.
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Trace Detection of Specific Viable Bacteria Using Tetracysteine-Tagged Bacteriophages.
Anal. Chem.
PUBLISHED: 12-10-2013
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Advanced methods are urgently needed to determine the identity and viability of trace amounts of pathogenic bacteria in a short time. Existing approaches either fall short in the accurate assessment of microbial viability or lack specificity in bacterial identification. Bacteriophages (or phages for short) are viruses that exclusively infect bacterial host cells with high specificity. As phages infect and replicate only in living bacterial hosts, here we exploit the strategy of using tetracysteine (TC)-tagged phage in combination with biarsenical dye to the discriminative detection of viable target bacteria from dead target cells and other viable but nontarget bacterial cells. Using recombinant M13KE-TC phage and Escherichia coli ER2738 as a model system, distinct differentiation between individual viable target cells from dead target cells was demonstrated by flow cytometry and fluorescence microscopy. As few as 1% viable E. coli ER2738 can be accurately quantified in a mix with dead E. coli ER2738 by flow cytometry. With fluorescence microscopic measurement, specific detection of as rare as 1 cfu/mL original viable target bacteria was achieved in the presence of a large excess of dead target cells and other viable but nontarget bacterial cells in 40 mL artificially contaminated drinking water sample in less than 3 h. This TC-phage-FlAsH approach is sensitive, specific, rapid, and simple, and thus shows great potential in water safety monitoring, health surveillance, and clinical diagnosis of which trace detection and identification of viable bacterial pathogens is highly demanded.
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[Analysis of reliability of the Chinese version of satisfaction with amplification in daily life].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 11-23-2013
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To investigate the reliability of the Chinese version of Satisfaction with Amplification in Daily Life (SADL).
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Investigating Cronobacter sakazakii responses to garlic-derived organosulfur compounds: a systematic study of pathogenic bacteria injury using high-throughput whole transcriptome sequencing and confocal micro-Raman spectroscopy.
Appl. Environ. Microbiol.
PUBLISHED: 11-22-2013
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We present the study using high-throughput whole transcriptome sequencing (RNA-seq) and vibrational spectroscopy to characterize and fingerprint pathogenic bacteria injury under unfavorable stress. Two garlic-derived organosulfur compounds were found to be highly effective antimicrobial compounds against Cronobacter sakazakii, a leading pathogen associated with invasive infection of infants causing meningitis, necrotizing entercolitis and bacteraemia. RNA-seq shows changes in gene expression patterns and transcriptomic response while confocal micro-Raman spectroscopy characterizes macromolecular changes in bacterial cell resulting from this chemical stress. RNA-seq analyses showed that the bacterial response to ajoene differed from diallyl sulfide. Specifically ajoene caused down regulation of motility related genes, while diallyl sulfide treatment caused an increased expression of cell wall synthesis genes. Confocal micro-Raman spectroscopy revealed that both compounds appear to have the same phase I antimicrobial mechanism of binding to thiol-containing proteins/enzymes in bacterial cells generating a disulfide stretching band, but a different phase II showing alterations in the secondary structures of proteins in two different ways. Diallyl sulfide primarily altered ?-helix and ?-sheet as reflected in changes in amide I while ajoene altered the structures containing phenylalanine and tyrosine. Bayesian probability validated the ability of principal component analysis to differentiate treated and control C. sakazakii cells. Scanning electron microscopy confirmed cell injury showing significant morphological variations in cells following treatments by these two compounds. Findings from this study aid in the development of effective intervention strategies to reduce the risk of C. sakazakii contamination in food production environment and food contact surfaces, reducing the risks to susceptible consumers.
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Clinical values of intraoperative indocyanine green fluorescence video angiography with Flow 800 software in cerebrovascular surgery.
Chin. Med. J.
PUBLISHED: 11-19-2013
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Microscope-integrated near-infrared indocyanine green video angiography (ICG-VA) has been used in neurosurgery for a decade. This study aimed to assess the value of intraoperative indocyanine green (ICG) video angiography with Flow 800 software in cerebrovascular surgery and to discover its hemodynamic features and changes of cerebrovascular diseases during surgery.
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[Establishment and evaluation of intraocular lens loop support force test platform].
Zhongguo Yi Liao Qi Xie Za Zhi
PUBLISHED: 11-08-2013
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Establish the test platform of the intraocular lens loop, and the platform was evaluated through the experiment.
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Regulation of the levels of Smad1 and Smad5 in MC3T3-E1 cells by Icariine in vitro.
Mol Med Rep
PUBLISHED: 11-04-2013
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The purpose of this study was to investigate the role of Icariine on the expression of Smadl and Smad5 mRNA and protein levels in MC3T3-E1 cells in vitro. MC3T3-E1 cells were cultured in the presence of different concentrations of Icariine (0, 10, 40 and 80 ng/ml). Smad1 and Smad5 mRNA levels were detected by reverse transcription-polymerase chain reaction (RT-PCR) and the expression of proteins was determined by western blotting, immunohistochemistry staining and immunofluorescence. Smad1 and Smad5 mRNA levels continuously increased in 10, 40 and 80 ng/ml of Icariine with time and the differences indicated statistical significance. Western blot analysis demonstrated that the Smad1 and Smad5 protein levels in the 10, 40 and 80 ng/ml groups were higher compared with the 0 ng/ml group at 24, 48 and 72 h, and the difference was statistically significant. Immunohistochemistry staining and immunofluorescence showed that the expression of the Smad1 and Smad5 proteins was higher in the cytoplasm and nuclei in the 10, 40 and 80 ng/ml groups compared with the 0 ng/ml group. Icariine has a direct stimulatory function on the differentiation of MC3T3-E1 osteoblastic cells in vitro, which may be mediated by increasing the production of Smad1 and Smad5 in osteoblasts.
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Structure-dependent inhibition of the ETS-family transcription factor PU.1 by novel heterocyclic diamidines.
Nucleic Acids Res.
PUBLISHED: 10-23-2013
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ETS transcription factors mediate a wide array of cellular functions and are attractive targets for pharmacological control of gene regulation. We report the inhibition of the ETS-family member PU.1 with a panel of novel heterocyclic diamidines. These diamidines are derivatives of furamidine (DB75) in which the central furan has been replaced with selenophene and/or one or both of the bridging phenyl has been replaced with benzimidazole. Like all ETS proteins, PU.1 binds sequence specifically to 10-bp sites by inserting a recognition helix into the major groove of a 5-GGAA-3 consensus, accompanied by contacts with the flanking minor groove. We showed that diamidines target the minor groove of AT-rich sequences on one or both sides of the consensus and disrupt PU.1 binding. Although all of the diamidines bind to one or both of the expected sequences within the binding site, considerable heterogeneity exists in terms of stoichiometry, site-site interactions and induced DNA conformation. We also showed that these compounds accumulate in live cell nuclei and inhibit PU.1-dependent gene transactivation. This study demonstrates that heterocyclic diamidines are capable of inhibiting PU.1 by targeting the flanking sequences and supports future efforts to develop agents for inhibiting specific members of the ETS family.
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Determination of ?-tocopherol in vegetable oils using a molecularly imprinted polymers-surface-enhanced Raman spectroscopic biosensor.
J. Agric. Food Chem.
PUBLISHED: 10-22-2013
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We report the development of a novel hybrid "capture-detection" molecularly imprinted polymers-surface-enhanced Raman spectroscopic (MIPs-SERS) biosensor for the detection and quantification of ?-tocopherol (?-Toc) in vegetable oils. ?-Toc served as the template for MIPs synthesis. Methacrylic acid formed as the functional monomer. Ethylene glycol dimethacrylate was the cross-linking agent, and 2,2-azobisisobutyronitrile was used as the initiator. The synthesized MIPs functioned to rapidly and selectively adsorb and separate ?-Toc from oil components. We validated a dendritic silver nanostructure synthesized by a displacement reaction to be a suitable SERS substrate for the enhancement of Raman signals. Second-derivative transformations and chemometric models based upon SERS spectral features confirmed the possibility of a rapid and precise detection and quantification of different spiking levels of ?-Toc in four different sources of vegetable oils (Mahalanobis distance from 15.93 to 34.01 for PCA model; R > 0.92, RMSE < 0.41 for PLSR model). The MIPs-SERS biosensor had a high sensitivity as well as a good recovery for ?-Toc analysis in vegetable oils. The entire analysis required 15 min or less to complete with limited sample preparation.
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Mechanism of formation of trans fatty acids under heating conditions in triolein.
J. Agric. Food Chem.
PUBLISHED: 10-17-2013
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To elucidate the relationship between heat-induced cis/trans isomerization and reaction temperature and energy in unsaturated lipids, we investigated the molecular mechanism of the heat-induced cis/trans isomerization of 18:1 isomers. Triolein (18:1,9c) was heated at two range temperatures (130, 160, 190, 220 °C and 135, 140, 145, 150, 155 °C) and analyzed by the gas chromatography (GC) method. When the heating temperature increased to 150 °C, the amount of trans 18:1n-9 changed from 0.0897 mg/g oil (1 h) to 0.1700 mg/g oil (3 h). This study shows that the cis to trans isomerization may occur at 150 °C. The formation of fatty acid isomers followed a proton transfer route. All key geometries, transition states, intermediates, and bond dissociation energies (BDE) were optimized at the B3LYP/6-31G* level for the density functional theory (DFT). The zero-point energy corrections of the isomers were carried out using calculations at the B3LYP/6-311++G** level. The calculated energy difference between the cis and trans oleic acid was equal to 7.6 kJ/mol, and the energy barriers of the transition from cis 18:1n-9 to trans 18:1n-9 were 294.5 kJ/mol. The intrinsic reaction coordinates (IRCs) were obtained to be used as an expression of the reaction route and to analyze the transition states and intermediates. The study results suggest that the heating temperature should be kept under 150 °C, to avoid the risk of trans fatty acid (TFA) intake in daily food.
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A 13µW 87dB dynamic range implantable ?? modulator for full-spectrum neural recording.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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Experiment analysis on in-vivo data sequences suggests a wide system dynamic range (DR) is required to simultaneously record local field potentials (LFPs), extra-cellular spikes, and artifacts/interferences. In this paper, we present a 13 µW 87 dB DR ?? modulator for full-spectrum neural recording. To achieve a wide DR and low power consumption, a fully-differential topology is used with multi-bit (MB) quantization scheme and switched-opamp (SO) technique. By adopting a novel fully-clocked scheme, a power-efficient current-mirror SO is developed with 50% power saving, which doubles the figure-of-merit (FOM) over its counterpart. A new static power-less multi-bit quantizer with 96% power and 69% area reduction is also introduced. Besides, instead of metal-insulator-metal (MIM) capacitor, three high-density MOS capacitor (MOSCAP) structures are employed to reduce circuit area. Measurement results show a peak signal-to-noise and distortion ratio (SNDR) of 85 dB with 10 kHz bandwidth at 1.0 V supply, corresponding to an FOM of 45 fJ/conv.-step. which is implemented in a 0.18 µm CMOS.
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[A study on the normal values of musical sounds in cochlear implants test battery].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 10-01-2013
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To establish music reference values for normal-hearing (NH) person in China, in order to give convenience in clinical application.
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Sensitive and selective electrochemical determination of quinoxaline-2-carboxylic acid based on bilayer of novel poly(pyrrole) functional composite using one-step electro-polymerization and molecularly imprinted poly(o-phenylenediamine).
Anal. Chim. Acta
PUBLISHED: 09-08-2013
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A facile and efficient molecularly imprinted polymer (MIP) recognition element of electrochemical sensor was fabricated by directly electro-polymerizing monomer o-phenylenediamine (oPD) in the presence of template quinoxaline-2-carboxylic acid (QCA), based on one-step controllable electrochemical modification of poly(pyrrole)-graphene oxide-binuclear phthalocyanine cobalt (II) sulphonate (PPY-GO-BiCoPc) functional composite on glassy carbon electrode (GCE). The MIP film coated on PPY-GO-BiCoPc functional composite decorated GCE (MIP/PPY-GO-BiCoPc/GCE) was presented for the first time. The synergistic effect and electro-catalytic activity toward QCA redox of PPY-GO-BiCoPc functional composite were discussed using various contrast tests. Also, the effect of experimental variables on the current response such as, electro-polymerization cycles, template/monomer ratio, elution condition for template removal, pH of the supporting electrolyte and accumulation time, were investigated in detail. Under the optimized conditions, the proposed MIP sensor possessed a fast rebinding dynamics and an excellent recognition capacity to QCA, while the anodic current response of square wave voltammetry (SWV) was well-proportional to the concentration of QCA in the range of 1.0×10(-8)-1.0×10(-4) and 1.0×10(-4)-5.0×10(-4)molL(-1) with a low detection limit of 2.1nmolL(-1). The established sensor was applied successfully to determine QCA in commercial pork and chicken muscle samples with acceptable recoveries (91.6-98.2%) and satisfactory precision (1.9-3.5% of SD), demonstrating a promising feature for applying the MIP sensor to the measurement of QCA in real samples.
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Comparison between laparoscopic and open partial nephrectomy: surgical, oncologic, and functional outcomes.
Kaohsiung J. Med. Sci.
PUBLISHED: 09-08-2013
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The surgical, oncologic, and functional outcomes were retrospectively compared of laparoscopic partial nephrectomy (LPN) and open partial nephrectomy (OPN) for the treatment of renal masses. Between January 2006 and November 2011, 115 LPNs and 97 OPNs were performed. The patients demographics were matched. Their intraoperative and postoperative data, oncologic and renal function outcomes were compared. Surgical time, renal arterial occlusion time, estimated blood loss, and postoperative hospitalization days were shorter in the LPN group (p < 0.01). The total complications were comparable; however, LPN had a higher intraoperative complication due to 12 subcutaneous emphysemas. The LPN group was followed up with a mean time of 29.3 ± 14.4 months and the OPN group with a mean time of 31.2 ± 12.6 months. All patients survived and no distant relapse or metastasis were observed. Kaplan-Meier estimates of 60-month local recurrence-free survival were comparable with 92.4% after LPN and 93.8% after OPN, respectively (p = 0.57). The reduction of glomerular filtration rate was more obvious after LPN at the 3-month follow-up (p < 0.01), but similar between the two groups at the 30.2-month follow-up. LPN provides similar results in oncologic and functional outcomes when compared to OPN. Long-term observations are still required to the oncologic and function outcomes.
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Creating dynamic images of short-lived dopamine fluctuations with lp-ntPET: dopamine movies of cigarette smoking.
J Vis Exp
PUBLISHED: 08-22-2013
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We describe experimental and statistical steps for creating dopamine movies of the brain from dynamic PET data. The movies represent minute-to-minute fluctuations of dopamine induced by smoking a cigarette. The smoker is imaged during a natural smoking experience while other possible confounding effects (such as head motion, expectation, novelty, or aversion to smoking repeatedly) are minimized. We present the details of our unique analysis. Conventional methods for PET analysis estimate time-invariant kinetic model parameters which cannot capture short-term fluctuations in neurotransmitter release. Our analysis--yielding a dopamine movie--is based on our work with kinetic models and other decomposition techniques that allow for time-varying parameters. This aspect of the analysis--temporal-variation--is key to our work. Because our model is also linear in parameters, it is practical, computationally, to apply at the voxel level. The analysis technique is comprised of five main steps: pre-processing, modeling, statistical comparison, masking and visualization. Preprocessing is applied to the PET data with a unique HYPR spatial filter that reduces spatial noise but preserves critical temporal information. Modeling identifies the time-varying function that best describes the dopamine effect on 11C-raclopride uptake. The statistical step compares the fit of our (lp-ntPET) model to a conventional model. Masking restricts treatment to those voxels best described by the new model. Visualization maps the dopamine function at each voxel to a color scale and produces a dopamine movie. Interim results and sample dopamine movies of cigarette smoking are presented.
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Single-neuron correlates of atypical face processing in autism.
Neuron
PUBLISHED: 08-20-2013
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People with autism spectrum disorder (ASD) show abnormal processing of faces. A range of morphometric, histological, and neuroimaging studies suggest the hypothesis that this abnormality may be linked to the amygdala. We recorded data from single neurons within the amygdalae of two rare neurosurgical patients with ASD. While basic electrophysiological response parameters were normal, there were specific and striking abnormalities in how individual facial features drove neuronal response. Compared to control patients, a population of neurons in the two ASD patients responded significantly more to the mouth, but less to the eyes. Moreover, we found a second class of face-responsive neurons for which responses to faces appeared normal. The findings confirm the amygdalas pivotal role in abnormal face processing by people with ASD at the cellular level and suggest that dysfunction may be traced to a specific subpopulation of neurons with altered selectivity for the features of faces.
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What is Visualize?

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

How does it work?

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

Video X seems to be unrelated to Abstract Y...

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.