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Find video protocols related to scientific articles indexed in Pubmed.
Protecting-Group-Free Total Synthesis of Aplykurodinone-1.
J. Org. Chem.
PUBLISHED: 11-11-2014
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A concise, stereoselective, and protecting-group-free total synthesis of aplykurodinone-1 from Hajos-Parrish ketone was described. The synthetic approach features a sequence of aerobic allylic oxidation and elimination of alcohol 9. The key intermediate for this synthesis was formed by a stereoselective intramolecular radical cyclization.
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Prostate CT segmentation method based on nonrigid registration in ultrasound-guided CT-based HDR prostate brachytherapy.
Med Phys
PUBLISHED: 11-06-2014
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The technological advances in real-time ultrasound image guidance for high-dose-rate (HDR) prostate brachytherapy have placed this treatment modality at the forefront of innovation in cancer radiotherapy. Prostate HDR treatment often involves placing the HDR catheters (needles) into the prostate gland under the transrectal ultrasound (TRUS) guidance, then generating a radiation treatment plan based on CT prostate images, and subsequently delivering high dose of radiation through these catheters. The main challenge for this HDR procedure is to accurately segment the prostate volume in the CT images for the radiation treatment planning. In this study, the authors propose a novel approach that integrates the prostate volume from 3D TRUS images into the treatment planning CT images to provide an accurate prostate delineation for prostate HDR treatment.
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[Long-term efficacy of CAMSBDH-ALL chemotherapy protocol for the treatment of childhood acute lymphoblastic leukemia].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 10-26-2014
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To study the long-term efficacy of CAMSBDH-ALL chemotherapy protocol for the treatment of childhood acute lymphoblastic leukemia (ALL).
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Simultaneous Phase Unwrapping and Removal of chemical Shift (SPURS) using Graph Cuts: Application in Quantitative Susceptibility Mapping.
IEEE Trans Med Imaging
PUBLISHED: 10-15-2014
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Quantitative Susceptibility Mapping (QSM) is a magnetic resonance imaging technique that reveals tissue magnetic susceptibility. It relies on having a high quality field map, typically acquired with a relatively long echo spacing and long final TE. Applications of QSM outside the brain require the removal of fat contributions to the total signal phase. However, current water/fat separation methods applied on typical data acquired for QSM suffer from three issues: inadequacy when using large echo spacing, over-smoothing of the field maps and high computational cost. In this paper, the general phase wrap and chemical shift problem is formulated using a single species fitting and is solved using graph cuts with conditional jump moves. This method is referred as Simultaneous Phase Unwrapping and Removal of chemical Shift (SPURS). The result from SPURS is then used as the initial guess for a voxel-wise Iterative Decomposition of water and fat with Echo Asymmetric and Least-squares estimation (IDEAL). The estimated three-dimensional field maps are used to compute Quantitative Susceptibility Maps (QSM) in body regions outside of the brain, such as the liver. Experimental results show substantial improvements in field map estimation, water/fat separation and reconstructed QSM compared to two existing water/fat separation methods on 1.5T and 3T magnetic resonance human data with long echo spacing and rapid field map variation.
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A Highly Stable Zeotype Mesoporous Zirconium Metal-Organic Framework with Ultralarge Pores.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 09-21-2014
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Through topological rationalization, a zeotype mesoporous Zr-containing metal-organic framework (MOF), namely PCN-777, has been designed and synthesized. PCN-777 exhibits the largest cage size of 3.8 nm and the highest pore volume of 2.8 cm(3) ?g(-1) among reported Zr-MOFs. Moreover, PCN-777 shows excellent stability in aqueous environments, which makes it an ideal candidate as a support to incorporate different functional moieties. Through facile internal surface modification, the interaction between PCN-777 and different guests can be varied to realize efficient immobilization.
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A Series of Highly Stable Mesoporous Metalloporphyrin Fe-MOFs.
J. Am. Chem. Soc.
PUBLISHED: 09-11-2014
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A series of mesoporous metalloporphyrin Fe-MOFs, namely PCN-600(M) (M = Mn, Fe, Co, Ni, Cu), have been synthesized using the preassembled [Fe3O(OOCCH3)6] building block. PCN-600 exhibits a one-dimensional channel as large as 3.1 nm and the highest experimental pore volume of 1.80 cm(3)g(-1) among all the reported porphyrinic MOFs. It also shows very high stability in aqueous solutions with pH values ranging from 2-11 and is to our knowledge the only mesoporous porphyrinic MOF stable under basic aqueous conditions. PCN-600(Fe) has been demonstrated as an effective peroxidase mimic to catalyze the co-oxidation reaction.
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The rare TREM2 R47H variant exerts only a modest effect on Alzheimer disease risk.
Neurology
PUBLISHED: 09-03-2014
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Recently, 2 independent studies reported that a rare missense variant, rs75932628 (R47H), in exon 2 of the gene encoding the "triggering receptor expressed on myeloid cells 2" (TREM2) significantly increases the risk of Alzheimer disease (AD) with an effect size comparable to that of the APOE ?4 allele.
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Multiple sclerosis lesion geometry in quantitative susceptibility mapping (QSM) and phase imaging.
J Magn Reson Imaging
PUBLISHED: 08-30-2014
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To demonstrate the phase and quantitative susceptibility mapping (QSM) patterns created by solid and shell spatial distributions of magnetic susceptibility in multiple sclerosis (MS) lesions.
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Significance of thrombocytosis in clinicopathologic characteristics and prognosis of gastric cancer.
Asian Pac. J. Cancer Prev.
PUBLISHED: 08-30-2014
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We aimed to study the relationship between thrombocytosis and clinical features of gastric cancer focussing on platelet counts and gastric cancer progression through different TNM stages.
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Transition-metal-free oxidative ?-C-H amination of ketones via a radical mechanism: mild synthesis of ?-amino ketones.
J. Org. Chem.
PUBLISHED: 08-29-2014
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A transition-metal-free direct ?-C-H amination of ketones has been developed using commercially available ammonium iodide as the catalyst and sodium percarbonate as the co-oxidant. A wide range of ketone ((hetero)aromatic or nonaromatic ketones) and amine (primary/secondary amines, anilines, or amides) substrates undergo cross-coupling to generate synthetically useful ?-amino ketones. The mechanistic studies indicated that a radical pathway might be involved in the reaction process. The utility of the method is highlighted through a concise one-step synthesis of the pharmaceutical agent amfepramone.
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A crystal structure-guided rational design switching non-carbohydrate inhibitors' specificity between two ?-GlcNAcase homologs.
Sci Rep
PUBLISHED: 08-26-2014
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Selective inhibition of function-specific ?-GlcNAcase has great potential in terms of drug design and biological research. The symmetrical bis-naphthalimide M-31850 was previously obtained by screening for specificity against human glycoconjugate-lytic ?-GlcNAcase. Using protein-ligand co-crystallization and molecular docking, we designed an unsymmetrical dyad of naphthalimide and thiadiazole, Q2, that changes naphthalimide specificity from against a human glycoconjugate-lytic ?-GlcNAcase to against insect and bacterial chitinolytic ?-GlcNAcases. The crystallographic and in silico studies reveal that the naphthalimide ring can be utilized to bind different parts of these enzyme homologs, providing a new starting point to design specific inhibitors. Moreover, Q2-induced closure of the substrate binding pocket is the structural basis for its 13-fold increment in inhibitory potency. Q2 is the first non-carbohydrate inhibitor against chitinolytic ?-GlcNAcases. This study provides a useful example of structure-based rationally designed inhibitors as potential pharmaceuticals or pesticides.
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Characterization and profiling of phenolic amides from Cortex Lycii by ultra-high performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry.
Anal Bioanal Chem
PUBLISHED: 08-25-2014
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Cortex Lycii, the root bark of Lycium chinense Mill. or Lycium barbarum L., is a frequently used traditional Chinese medicine. Phytochemical studies have shown that phenolic amides are not only characteristic compounds but also abundant ones in this plant. In the present study, an effective method was developed for structural characterization of phenolic amides from Cortex Lycii by ultra-high performance liquid chromatography coupled with linear ion trap Orbitrap tandem mass spectrometry. The fragmentation of 14 compounds including six cinnamic acid amides, six neolignanamides, and two lignanamides were studied systematically for the first time. It was found that, in the positive ion mode, neutral loss of the tyramide moiety (137 Da) or N-(4-aminobutyl)acetamide moiety (130 Da) were characteristic for these compounds. At least 54 phenolic amides were detected in the extract and 48 of them were characterized, among which 14 known compounds were identified unambiguously by comparing the retention time and mass spectra with those of reference compounds, and 34 components were tentatively identified based on the fragmentation patterns, exact mass, UV spectra, as well as retention time. Fifteen compounds were characterized as potential new ones. Additionally, the developed method was applied to analyze eight batches of samples collected from the northwest of China, and it was found that cinnamic acid amides were the main type of phenolic amides in Cortex Lycii. In conclusion, the identification of these chemicals provided essential data for further phytochemical studies, metabolites identification, and the quality control of Cortex Lycii.
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[Effects of controllable dynamic inhaled exposure of moxa smoke on LDL-r, ICAM-1 and morphology of heart tissue in rats].
Zhongguo Zhen Jiu
PUBLISHED: 08-13-2014
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To observe the change of lipid metabolism and vascular endothelium as well as morphology of heart tissue in rats who were long-time exposed to moxa smoke with different concentrations in order to provide reference for safety assessment of moxa smoke on cardiovascular system.
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Development of a time-resolved fluorescence immunoassay for herpes simplex virus type 1 and type 2 IgG antibodies.
Luminescence
PUBLISHED: 07-22-2014
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Enzyme-linked immunosorbent assays (ELISA) specific for anti-HSV glycoprotein G (gG) are most commonly used in the clinical diagnosis of HSV infection. But most of them are qualitative and with narrow detection ranges. A novel time-resolved fluoroimmunoassay (TRFIA) methodology was developed for the quantitative determination of HSV IgG in human serum. The assay was based on an indirect immunoassay format, and performed in 96-well microtiter plates. HSV-1 and HSV-2 were used as the coating antigens. Eu(3+) -labeled goat anti-(human IgG) polyclonal antibodies were used as tracers. The fluorescence intensity of each well was measured and serum HSV IgG levels quantified against a calibration curve. The detection range of the novel TRFIA was between 5 and 500?AU/mL. Assay sensitivity was 0.568?AU/mL. The intra- and inter-assay coefficients of variation were 0.59-3.63% and 3.65-6.81%, respectively. Analytical recovery, dilution tests and serum panel tests were performed using TRFIA and the results proved satisfactory. There were no statistically significant differences in sensitivity and specificity between the TRFIA and commercial ELISAs. An effective, sensitive and accurate quantitative HSV type 1 and type 2 IgG TRFIA was successfully developed and provided diagnostic value in clinical use. Copyright © 2014 John Wiley & Sons, Ltd.
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Phase-corrected bipolar gradients in multi-echo gradient-echo sequences for quantitative susceptibility mapping.
MAGMA
PUBLISHED: 07-14-2014
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Large echo spacing of unipolar readout gradients in current multi-echo gradient-echo (GRE) sequences for mapping fields in quantitative susceptibility mapping (QSM) can be reduced using bipolar readout gradients thereby improving acquisition efficiency.
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Internal structures of the globus pallidus in patients with Parkinson's disease: evaluation with quantitative susceptibility mapping (QSM).
Eur Radiol
PUBLISHED: 06-29-2014
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The aim of this study was to assess the susceptibility change in medial and lateral globus pallidus (GPm and GPl) related to age separately, using quantitative susceptibility mapping (QSM) and to determine whether QSM can depict GPm in Parkinson's disease (PD) patients.
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Pathophysiological roles of adrenomedullin-RAMP2 system in acute and chronic cerebral ischemia.
Peptides
PUBLISHED: 06-26-2014
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The accessory protein RAMP2 is a component of the CLR/RAMP2 dimeric adrenomedullin (AM) receptor and is the primary determinant of the vascular functionality of AM. RAMP2 is highly expressed in the brain; however, its function there remains unclear. We therefore used heterozygous RAMP2 knockout (RAMP2+/-) mice, in which RAMP2 expression was reduced by half, to examine the actions of the endogenous AM-RAMP2 system in cerebral ischemia. To induce acute or chronic ischemia, mice were subjected to middle cerebral artery occlusion (MCAO) or bilateral common carotid artery stenosis (BCAS), respectively. In RAMP2+/- mice subjected to MCAO, recovery of cerebral blood flow (CBF) was slower than in WT mice. AM gene expression was upregulated after infarction in both genotypes, but the increase was greater in RAMP2+/- mice. Pathological analysis revealed severe nerve cell death and demyelination, and a higher level of oxidative stress in RAMP2+/- mice. In RAMP2+/- mice subjected to BCAS, recovery of cerebral perfusion was slower and less complete than in WT mice. In an 8-arm radial maze test, RAMP2+/- mice required more time to solve the maze and showed poorer reference memory. They also showed greater reductions in nerve cells and less compensatory capillary growth than WT mice. These results indicate the AM-RAMP2 system works to protect nerve cells from both acute and chronic cerebral ischemia by maintaining CBF, suppressing oxidative stress, and in the case of chronic ischemia, enhancing capillary growth.
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Electroencephalogram synchronization analysis for attention deficit hyperactivity disorder children.
Biomed Mater Eng
PUBLISHED: 06-24-2014
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This study investigated the changes in synchronization of different electroencephalogram (EEG) bands in attention deficit hyperactivity disorder (ADHD) children. EEG data were obtained from 13 children diagnosed with ADHD and 13 normal control children in the resting state. The statistical dependencies between each EEG channel were generated by calculating synchronization likelihood. The differences of synchronization between the ADHD and control groups were statistically evaluated. Overall, the synchronization was significantly higher in the ADHD group in the alpha and beta bands. The present study found that synchronization was significantly altered in the fast EEG bands in patients with ADHD. These findings may enhance our understanding for the relationship between ADHD and cerebral dysfunction.
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Quantitative mapping of cerebral metabolic rate of oxygen (CMRO2 ) using quantitative susceptibility mapping (QSM).
Magn Reson Med
PUBLISHED: 06-20-2014
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To quantitatively map cerebral metabolic rate of oxygen ( CMRO2) and oxygen extraction fraction ( OEF) in human brains using quantitative susceptibility mapping (QSM) and arterial spin labeling-measured cerebral blood flow (CBF) before and after caffeine vasoconstriction.
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Functional differentiation of RAMP2 and RAMP3 in their regulation of the vascular system.
J. Mol. Cell. Cardiol.
PUBLISHED: 06-11-2014
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Adrenomedullin (AM) is a vasoactive peptide that possesses various bioactivities. AM receptors are dimers consisting of CLR with one of two accessory proteins, RAMP2 or RAMP3. The functional difference between CLR/RAMP2 and CLR/RAMP3 and the relationship between the two receptors remain unclear. To address these issues, we generated RAMP2 and RAMP3 knockout (-/-) mice and have been studying their physiological activities in the vascular system. AM-/- and RAMP2-/- mice die in utero due to blood vessel abnormalities, which is indicative of their essential roles in vascular development. In contrast, RAMP3-/- mice were born normally without any major abnormalities. In adult RAMP3-/- mice, postnatal angiogenesis was normal, but lymphangiography using indocyanine green (ICG) showed delayed drainage of subcutaneous lymphatic vessels. Moreover, chyle transport by intestinal lymphatics was delayed in RAMP3-/- mice, which also showed more severe interstitial edema than wild-type mice in a tail lymphedema model, with characteristic dilatation of lymphatic capillaries and accumulation of inflammatory cells. In scratch-wound assays, migration of isolated RAMP3-/- lymphatic endothelial cells was delayed as compared to wild-type cells, and AM administration failed to enhance the re-endothelialization. The delay in re-endothelialization was due to a primary migration defect rather than a decrease in proliferation. These results suggest that RAMP3 regulates drainage through lymphatic vessels, and that the AM-RAMP3 system could be a novel therapeutic target for controlling postoperative lymphedema.
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Detection of quiescent cardiac phases in echocardiography data using nonlinear filtering and boundary detection techniques.
J Digit Imaging
PUBLISHED: 05-27-2014
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We describe an algorithm to detect cardiac quiescence within a heartbeat using nonlinear filtering and boundary detection techniques in echocardiography images. The motivation for detection of these quiescent phases is to provide improved cardiac gating to obtain motion-artifact-free images of the heart at cardiac computed tomography (CT). Currently, cardiac gating is provided through electrocardiography (ECG), which does not provide information about the instantaneous mechanical state of the heart. Our goal is to test if information about the actual mechanical motion of the heart obtained from B-mode echocardiographic data could potentially be used for gating purposes. The nonlinear filtering algorithm presented involves anisotropic diffusion to smoothen the homogeneous regions of the B-mode images while preserving image edges that represent myocardial boundaries. Following this, we detect the boundary of a particular region of interest (ROI) using a thresholding step. The positional changes of this ROI are then observed for quiescent phases over multiple cardiac cycles using the ECG's R-R interval. In a pilot study, seven subjects were imaged in the apical, four-chamber view, and quiescence of the interventricular septum was primarily observed in the diastolic region of the ECG signal. However, the position and length of quiescence vary across multiple heartbeats for the same individual and for different individuals as well. The center of quiescence for the seven patients ranged from 51 to 84 % and did not show a trend with heart rates, which ranged from 54 to 83 beats per minute. The gating intervals based on such analysis of echocardiographic signals could potentially optimize cardiac CT gating.
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Stepwise synthesis of robust metal-organic frameworks via postsynthetic metathesis and oxidation of metal nodes in a single-crystal to single-crystal transformation.
J. Am. Chem. Soc.
PUBLISHED: 05-23-2014
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Utilizing PCN-426-Mg as a template, two robust metal-organic frameworks (MOFs), PCN-426-Fe(III) and PCN-426-Cr(III), have been synthesized through a strategy of postsynthetic metathesis and oxidation (PSMO) of the metal nodes step by step. The frameworks remained in their single crystal form throughout. Furthermore, the stability and porosity of the frameworks were significantly improved after PSMO. By taking advantage of both the kinetically labile metal-ligand exchange reactions prior to oxidation and the kinetically inert metal-ligand bonds after oxidation, robust MOFs, which would otherwise be difficult to synthesize, can be readily prepared.
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Lower baseline performance but greater plasticity of working memory for carriers of the val allele of the comt val158met polymorphism.
Neuropsychology
PUBLISHED: 05-14-2014
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Objective: Little is known about genetic contributions to individual differences in cognitive plasticity. Given that the neurotransmitter dopamine is critical for cognition and associated with cognitive plasticity, we investigated the effects of 3 polymorphisms of dopamine-related genes (LMX1A, DRD2, COMT) on baseline performance and plasticity of working memory (WM), perceptual speed, and reasoning. Method: One hundred one younger and 103 older adults underwent approximately 100 days of cognitive training, and extensive testing before and after training. We analyzed the baseline and posttest data using latent change score models. Results: For working memory, carriers of the val allele of the COMT polymorphism had lower baseline performance and larger performance gains from training than carriers of the met allele. There was no significant effect of the other genes or on other cognitive domains. Conclusions: We relate this result to available evidence indicating that met carriers perform better than val carriers in WM tasks taxing maintenance, whereas val carriers perform better at updating tasks. We suggest that val carriers may show larger training gains because updating operations carry greater potential for plasticity than maintenance operations. (PsycINFO Database Record (c) 2014 APA, all rights reserved).
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Regulatory mechanism of pyrrolidine dithiocarbamate is mediated by nuclear factor-?B and inhibits neutrophil accumulation in ARDS mice.
Exp Ther Med
PUBLISHED: 04-29-2014
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The aim of the present study was to investigate the regulatory mechanism of nuclear factor (NF)-?B on polymorphonuclear neutrophil (PMN) accumulation and the inflammatory response in lung tissues with acute respiratory distress syndrome (ARDS), as well as the therapeutic effect of pyrrolidine dithiocarbamate (PDTC). Mouse models of ARDS were established by intraperitoneal injection of lipopolysaccharide (LPS). BALB/c mice were divided into control, LPS and PDTC + LPS groups. The expression of PMN adhesion molecules, CD11b/CD18 and intercellular adhesion molecule-1 (ICAM-1), were detected by immunohistochemistry, while the protein expression levels of NF-?B p65 in the lung tissue were analyzed by western blot analysis. In addition, flow cytometry was used to investigate the apoptosis rate of PMNs in the bronchoalveolar fluid, and the expression levels of interleukin (IL)-1?, IL-8 and tumor necrosis factor (TNF)-? and myeloperoxidase (MPO) activity were also determined. Following an intraperitoneal injection of LPS, alveolar septum rupture, pulmonary interstitial hyperemia and PMN infiltration in the alveolar was observed. The protein expression of p65 in the pulmonary cytoplasm decreased, while the expression of p65 in the nucleus increased. The levels of IL-8, IL-1? and TNF-? increased and the high expression status was maintained for 24 h. As the time increased, CD11b/CD18 and ICAM-1 expression increased, as well as MPO activity, while the apoptosis of PMNs was delayed. Compared with the LPS group, the expression of p65 in the pulmonary cytoplasm and the PMN apoptosis rate increased following PDTC intervention, while the expression of p65 in the nucleus decreased, as well as the expression levels of the cytokines and MPO activity. Therefore, PDTC reduced the production of inflammatory cytokines via the NF-?B pathway, which reduced the activation of PMNs in the lung tissue and promoted PMN apoptosis.
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Modulation of mitochondrial function by stem cell-derived cellular components.
Biochem. Biophys. Res. Commun.
PUBLISHED: 04-18-2014
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Huntington's disease (HD) is the most common hereditary neurodegenerative diseases, in which the loss of striatal neuron caused by the aggregation of mutant huntingtin protein (mHtt) is the main pathological feature. Our previous studies have demonstrated that human adipose stem cells (hASC) and its extracts can slow down the progression of HD in vitro and in vivo. hASC are readily accessible adult stem cells, and the cytosolic extracts contain a number of neurotrophic factors. Here, we further explored the role of the hASC extracts in neuronal death and mitochondrial function in HD. Our results showed that the hASC extracts prevent mHtt-induced cell toxicity and cell apoptosis. Moreover, the hASC extracts recovered mHtt-induced mitochondrial oxidative stress and reduced mitochondrial membrane potential. The hASC extracts blocked the interaction between p53 and mHtt, and decreased the endogenous p53 levels at both transcriptional and post-translational levels, resulting in the instability of p53 and increased neuronal survival. Taken together, these findings implicate protective roles of hASC extracts in mHtt-induced mitochondrial apoptosis, providing insights into the molecular mechanism of the hASC in the therapeutic strategy of HD.
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Small-World Brain Functional Networks in Children With Attention-Deficit/Hyperactivity Disorder Revealed by EEG Synchrony.
Clin EEG Neurosci
PUBLISHED: 04-05-2014
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We investigated the topologic properties of human brain attention-related functional networks associated with Multi-Source Interference Task (MSIT) performance using electroencephalography (EEG). Data were obtained from 13 children diagnosed with attention-deficit/hyperactivity disorder (ADHD) and 13 normal control children. Functional connectivity between all pairwise combinations of EEG channels was established by calculating synchronization likelihood (SL). The cluster coefficients and path lengths were computed as a function of degree K. The results showed that brain attention functional networks of normal control subjects had efficient small-world topologic properties, whereas these topologic properties were altered in ADHD. In particular, increased local characteristics combined with decreased global characteristics in ADHD led to a disorder-related shift of the network topologic structure toward ordered networks. These findings are consistent with a hypothesis of dysfunctional segregation and integration of the brain in ADHD, and enhance our understanding of the underlying pathophysiologic mechanism of this illness.
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[Effect of Qufeng Tongluo Recipe on expression of desmin and CD2AP proteins in adriamycin-induced nephropathy rats: an experimental research].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 03-29-2014
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To investigate the effect of Qufeng Tongluo Recipe (QTR) on the expression of desmin and CD2-associated protein (CD2AP) in adriamycin-induced nephropathy rats.
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Quantification of cerebral perfusion using dynamic quantitative susceptibility mapping.
Magn Reson Med
PUBLISHED: 03-27-2014
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The purpose of this study is to develop a dynamic quantitative susceptibility mapping (QSM) technique with sufficient temporal resolution to map contrast agent concentration in cerebral perfusion imaging.
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The Val/Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene predicts decline in perceptual speed in older adults.
Psychol Aging
PUBLISHED: 03-24-2014
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The brain-derived neurotrophic factor (BDNF) promotes activity-dependent synaptic plasticity, and contributes to learning and memory. We investigated whether a common Val66Met missense polymorphism (rs6265) of the BDNF gene is associated with individual differences in cognitive decline (marked by perceptual speed) in old age. A total of 376 participants of the Berlin Aging Study, with a mean age of 83.9 years at first occasion, were assessed longitudinally up to 11 times across more than 13 years on the Digit-Letter task. Met carriers (n = 123, 34%) showed steeper linear decline than Val homozygotes (n = 239, 66%); the corresponding contrast explained 2.20% of the variance in change in the entire sample, and 3.41% after excluding individuals at risk for dementia. These effects were not moderated by sex or socioeconomic status. Results are consistent with the hypothesis that normal aging magnifies the effects of common genetic variation on cognitive functioning.
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Structural characteristics of an insect group I chitinase, an enzyme indispensable to moulting.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 03-19-2014
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Insects possess a greater number of chitinases than any other organisms. This work is the first report of unliganded and oligosaccharide-complexed crystal structures of the insect chitinase OfChtI from Ostrinia furnacalis, which is essential to moulting. The obtained crystal structures were solved at resolutions between 1.7 and 2.2?Å. A structural comparison with other chitinases revealed that OfChtI contains a long substrate-binding cleft similar to the bacterial chitinase SmChiB from Serratia marcescens. However, unlike the exo-acting SmChiB, which has a blocked and tunnel-like cleft, OfChtI possesses an open and groove-like cleft. The complexed structure of the catalytic domain of OfChtI (OfChtI-CAD) with (GlcNAc)2/3 indicates that the reducing sugar at subsite -1 is in an energetically unfavoured `boat' conformation, a state that possibly exists just before the completion of catalysis. Because OfChtI is known to act from nonreducing ends, (GlcNAc)3 would be a hydrolysis product of (GlcNAc)6, suggesting that OfChtI possesses an endo enzymatic activity. Furthermore, a hydrophobic plane composed of four surface-exposed aromatic residues is adjacent to the entrance to the substrate-binding cleft. Mutations of these residues greatly impair the chitin-binding activity, indicating that this hydrophobic plane endows OfChtI-CAD with the ability to anchor chitin. This work reveals the unique structural characteristics of an insect chitinase.
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Quantitative susceptibility mapping (QSM): Decoding MRI data for a tissue magnetic biomarker.
Magn Reson Med
PUBLISHED: 03-13-2014
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In MRI, the main magnetic field polarizes the electron cloud of a molecule, generating a chemical shift for observer protons within the molecule and a magnetic susceptibility inhomogeneity field for observer protons outside the molecule. The number of water protons surrounding a molecule for detecting its magnetic susceptibility is vastly greater than the number of protons within the molecule for detecting its chemical shift. However, the study of tissue magnetic susceptibility has been hindered by poor molecular specificities of hitherto used methods based on MRI signal phase and T2* contrast, which depend convolutedly on surrounding susceptibility sources. Deconvolution of the MRI signal phase can determine tissue susceptibility but is challenged by the lack of MRI signal in the background and by the zeroes in the dipole kernel. Recently, physically meaningful regularizations, including the Bayesian approach, have been developed to enable accurate quantitative susceptibility mapping (QSM) for studying iron distribution, metabolic oxygen consumption, blood degradation, calcification, demyelination, and other pathophysiological susceptibility changes, as well as contrast agent biodistribution in MRI. This paper attempts to summarize the basic physical concepts and essential algorithmic steps in QSM, to describe clinical and technical issues under active development, and to provide references, codes, and testing data for readers interested in QSM. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc.
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Evaluation of iron content in human cerebral cavernous malformation using quantitative susceptibility mapping.
Invest Radiol
PUBLISHED: 03-13-2014
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The aims of this study were to investigate and validate quantitative susceptibility mapping (QSM) for lesional iron quantification in cerebral cavernous malformations (CCMs).
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Tuning the structure and function of metal-organic frameworks via linker design.
Chem Soc Rev
PUBLISHED: 03-08-2014
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Metal-organic frameworks (MOFs) are constructed from metal ions/clusters coordinated by organic linkers (or bridging-ligands). The hallmark of MOFs is their permanent porosity, which is frequently found in MOFs constructed from metal-clusters. These clusters are often formed in situ, whereas the linkers are generally pre-formed. The geometry and connectivity of a linker dictate the structure of the resulting MOF. Adjustments of linker geometry, length, ratio, and functional-group can tune the size, shape, and internal surface property of a MOF for a targeted application. In this critical review, we highlight advances in MOF synthesis focusing on linker design. Examples of building MOFs to reach unique properties, such as unprecedented surface area, pore aperture, molecular recognition, stability, and catalysis, through linker design are described. Further search for application-oriented MOFs through judicious selection of metal clusters and organic linkers is desirable. In this review, linkers are categorized as ditopic (Section 1), tritopic (Section 2), tetratopic (Section 3), hexatopic (Section 4), octatopic (Section 5), mixed (Section 6), desymmetrized (Section 7), metallo (Section 8), and N-heterocyclic linkers (Section 9).
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Diagnostic accuracy of ultrasonic histogram features to evaluate radiation toxicity of the parotid glands: a clinical study of xerostomia following head-and-neck cancer radiotherapy.
Acad Radiol
PUBLISHED: 03-06-2014
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To investigate the diagnostic accuracy of ultrasound histogram features in the quantitative assessment of radiation-induced parotid gland injury and to identify potential imaging biomarkers for radiation-induced xerostomia (dry mouth)-the most common and debilitating side effect after head-and-neck radiotherapy (RT).
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Ultrasonic Nakagami-parameter characterization of parotid-gland injury following head-and-neck radiotherapy: a feasibility study of late toxicity.
Med Phys
PUBLISHED: 02-11-2014
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The study aims to investigate whether Nakagami parameters--estimated from the statistical distribution of the backscattered ultrasound radio-frequency (RF) signals--could provide a means for quantitative characterization of parotid-gland injury resulting from head-and-neck radiotherapy.
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Joint estimation of chemical shift and quantitative susceptibility mapping (chemical QSM).
Magn Reson Med
PUBLISHED: 02-07-2014
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The purpose of this work is to address the unsolved problem of quantitative susceptibility mapping (QSM) of tissue with fat where both fat and susceptibility change the MR signal phase.
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Quantitative susceptibility mapping of multiple sclerosis lesions at various ages.
Radiology
PUBLISHED: 01-31-2014
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To assess multiple sclerosis (MS) lesions at various ages by using quantitative susceptibility mapping (QSM) and conventional magnetic resonance (MR) imaging.
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Expression and significance of E-cadherin, N-cadherin, transforming growth factor-?1 and Twist in prostate cancer.
Asian Pac J Trop Med
PUBLISHED: 01-15-2014
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To study the expression of E-cadherin, N-cadherin, TGF-?1 and Twist protein and investigate its significance in the occurrence and development of prostate cancer.
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Influence of the gastrointestinal microflora and efflux transporters on the absorption of scutellarin and scutellarein.
Phytother Res
PUBLISHED: 01-10-2014
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Scutellarin (SG) and its aglycone, Scutellarein (S), are flavonoids of therapeutic cardiocerebrovascular disease. SG was hydrolyzed by bacterial enzyme into S which was absorbed in the intestine. The aim of this study was to determine the effects of the microflora in the intestinal lumen and the efflux transporter of intestinal epithelial cells on the absorption process of SG and S. After oral administration of antibiotics in Sprague-Dawley rats, the reduced bacterial enzyme formation significantly hinders the absorption of SG, whereas scarcely that of S. The absorption study in situ single-pass intestinal perfusion revealed that S could be absorbed throughout the intestine of rats. The effective intestinal permeability of S in the jejunum was much lower than in the other sections of the GI tract. The efflux transporter promoted SG secretion into lumen from enterocytes, which hindered the absorption of both SG and S into the bloodstream. The efflux transporter protein inhibitor (verapamil, probenecid and reserpine) remarkably enhanced the absorption of S and the bioconversion of S into SG in both the rat intestine and Caco-2-monolayer models.
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Background field removal by solving the Laplacian boundary value problem.
NMR Biomed
PUBLISHED: 01-07-2014
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The removal of the background magnetic field is a critical step in generating phase images and quantitative susceptibility maps, which have recently been receiving increasing attention. Although it is known that the background field satisfies Laplace's equation, the boundary values of the background field for the region of interest have not been explicitly addressed in the existing methods, and they are not directly available from MRI measurements. In this paper, we assume simple boundary conditions and remove the background field by explicitly solving the boundary value problems of Laplace's or Poisson's equation. The proposed Laplacian boundary value (LBV) method for background field removal retains data near the boundary and is computationally efficient. Tests on a numerical phantom and an experimental phantom showed that LBV was more accurate than two existing methods.
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Development of an improved time-resolved fluoroimmunoassay for simultaneous quantification of C-peptide and insulin in human serum.
Clin. Biochem.
PUBLISHED: 01-06-2014
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Diabetes mellitus is a chronic disease affecting millions of people globally and resulting in significant death rates each year. A fast, inexpensive alternative to traditional testing and monitoring techniques is desirable, since secretion of insulin and C-peptide is impaired in diabetes mellitus.
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MicroRNA-138 is a potential regulator of memory performance in humans.
Front Hum Neurosci
PUBLISHED: 01-01-2014
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Genetic factors underlie a substantial proportion of individual differences in cognitive functions in humans, including processes related to episodic and working memory. While genetic association studies have proposed several candidate "memory genes," these currently explain only a minor fraction of the phenotypic variance. Here, we performed genome-wide screening on 13 episodic and working memory phenotypes in 1318 participants of the Berlin Aging Study II aged 60 years or older. The analyses highlight a number of novel single nucleotide polymorphisms (SNPs) associated with memory performance, including one located in a putative regulatory region of microRNA (miRNA) hsa-mir-138-5p (rs9882688, P-value = 7.8 × 10(-9)). Expression quantitative trait locus analyses on next-generation RNA-sequencing data revealed that rs9882688 genotypes show a significant correlation with the expression levels of this miRNA in 309 human lymphoblastoid cell lines (P-value = 5 × 10(-4)). In silico modeling of other top-ranking GWAS signals identified an additional memory-associated SNP in the 3' untranslated region (3' UTR) of DCP1B, a gene encoding a core component of the mRNA decapping complex in humans, predicted to interfere with hsa-mir-138-5p binding. This prediction was confirmed in vitro by luciferase assays showing differential binding of hsa-mir-138-5p to 3' UTR reporter constructs in two human cell lines (HEK293: P-value = 0.0470; SH-SY5Y: P-value = 0.0866). Finally, expression profiling of hsa-mir-138-5p and DCP1B mRNA in human post-mortem brain tissue revealed that both molecules are expressed simultaneously in frontal cortex and hippocampus, suggesting that the proposed interaction between hsa-mir-138-5p and DCP1B may also take place in vivo. In summary, by combining unbiased genome-wide screening with extensive in silico modeling, in vitro functional assays, and gene expression profiling, our study identified miRNA-138 as a potential molecular regulator of human memory function.
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Cervical cancer cells with positive Sox2 expression exhibit the properties of cancer stem cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Although Sox2 expression has been found in several types of cancer, it has not yet been used to identify or isolate CSCs in somatic carcinoma.
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Dynamic Permeability and Quantitative Susceptibility: Related Imaging Biomarkers in Cerebral Cavernous Malformations.
Stroke
PUBLISHED: 12-03-2013
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Hyperpermeability and iron deposition are 2 central pathophysiological phenomena in human cerebral cavernous malformation (CCM) disease. Here, we used 2 novel MRI techniques to establish a relationship between these phenomena.
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[The gene mutation screening of a family with congenital fibrosis of the extraocular muscles associated with corpus callosum agenesis].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 11-22-2013
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To identify TUBB3 gene mutations in a Chinese family with congenital fibrosis of the extraocular muscle associated with corpus callosum agenesis.
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[Effect of early intervention of liver-smoothing and blood-activating decoction combined with acupuncture on patients with post-stroke depression].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-09-2013
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To study the effect of early intervention of liver-soothing and Blood-activating decoction combined with acupuncture in improving neurological functions, depressive symptom and life quality of patients with post-stroke depression, and compare with fluoxetine hydrochloride. Specifically, 63 patients with post-stroke depression were randomly divided into the traditional Chinese medicine (TCM) acupuncture group (31 cases) and the western medicine group (32 cases). On the basis of the conventional treatment of the primary disease, the TCM acupuncture group was treated with liver-soothing and blood-activating decoction and acupuncture, while the western medicine group was treated with fluoxetine hydrochloride for four weeks. In the follow-up visit six months later, scores of HAMD, NIHSS and SS-QOL were observed. The scores of HAMD and NIHSS of both groups were significantly decreased (P < 0.01), while the scores of SS-QOL increased significantly, with a notable difference compared with that before the treatment (P < 0.01). Specifically, the TCM acupuncture groups was superior to the western medicine group (P < 0.05). The study suggests that the early intervention of liver-soothing and blood-activating decoction combined with acupuncture on patients with post-stroke depression has the effect in relieving depression symptom and improving neurological functions, thereby improving their quality of life and prognosis.
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[Establishment of an N-2a cell line stably expressing mouse galanin and the effect of over-expressed galanin on the proliferation and apoptosis of N-2a cell].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 11-05-2013
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To construct an N-2a cell line stably expressing PcDNA 3.1-platelet derived growth factor-galanin(GAL)and explore the effect of over-expressed GAL on proliferation and apoptosis of N-2a cell in vitro.
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Intracranial Calcifications and Hemorrhages: Characterization with Quantitative Susceptibility Mapping.
Radiology
PUBLISHED: 10-28-2013
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Purpose:To compare gradient-echo (GRE) phase magnetic resonance (MR) imaging and quantitative susceptibility mapping (QSM) in the detection of intracranial calcifications and hemorrhages.Materials and Methods:This retrospective study was approved by the institutional review board. Thirty-eight patients (24 male, 14 female; mean age, 33 years ± 16 [standard deviation]) with intracranial calcifications and/or hemorrhages diagnosed on the basis of computed tomography (CT), MR imaging (interval between examinations, 1.78 days ± 1.31), and clinical information were selected. GRE and QSM images were reconstructed from the same GRE data. Two experienced neuroradiologists independently identified the calcifications and hemorrhages on the QSM and GRE phase images in two randomized sessions. Sensitivity, specificity, and interobserver agreement were computed and compared with the McNemar test and ? coefficients. Calcification loads and volumes were measured to gauge intermodality correlations with CT.Results:A total of 156 lesions were detected: 62 hemorrhages, 89 calcifications, and five mixed lesions containing both hemorrhage and calcification. Most of these lesions (146 of 151 lesions, 96.7%) had a dominant sign on QSM images suggestive of a specific diagnosis of hemorrhage or calcium, whereas half of these lesions (76 of 151, 50.3%) were heterogeneous on GRE phase images and thus were difficult to characterize. Averaged over the two independent observers for detecting hemorrhages, QSM achieved a sensitivity of 89.5% and a specificity of 94.5%, which were significantly higher than those at GRE phase imaging (71% and 80%, respectively; P < .05 for both readers). In the identification of calcifications, QSM achieved a sensitivity of 80.5%, which was marginally higher than that with GRE phase imaging (71%; P = .08 and .10 for the two readers), and a specificity of 93.5%, which was significantly higher than that with GRE phase imaging (76.5%; P < .05 for both readers). QSM achieved significantly better interobserver agreements than GRE phase imaging in the differentiation of hemorrhage from calcification (?: 0.91 vs 0.55, respectively; P < .05).Conclusion:QSM is superior to GRE phase imaging in the differentiation of intracranial calcifications from hemorrhages and with regard to the sensitivity and specificity of detecting hemorrhages and the specificity of detecting calcifications.© RSNA, 2013Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13122640/-/DC1.
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O-GlcNAcPRED: a sensitive predictor to capture protein O-GlcNAcylation sites.
Mol Biosyst
PUBLISHED: 09-13-2013
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O-GlcNAcylation is a ubiquitous post-translational modification of proteins that is involved in the majority of cellular processes and is associated with many diseases. To reduce the workload and increase the relevance of experimental identification of protein O-GlcNAcylation sites, O-GlcNAcPRED, a support vector machine (SVM)-based model, was developed to capture potential O-GlcNAcylation sites. By virtue of the novel adapted normal distribution bi-profile Bayes (ANBPB) feature extraction method, O-GlcNAcPRED yielded a sensitivity of 80.83%, a specificity of 78.17% and an accuracy of 79.50% in jackknife cross-validation experiments. In an independent test on 38 recently experimentally identified human O-GlcNAcylated proteins with 67 O-GlcNAcylation sites, O-GlcNAcPRED captured 26 proteins and 39 sites, clearly outperforming the existing predictors, YinOYang and O-GlcNAcscan.
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[Interference of vitamin E on the brain tissue damage by electromagnetic radiation of cell phone in pregnant and fetal rats].
Wei Sheng Yan Jiu
PUBLISHED: 09-13-2013
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To investigate the interlerence ot vitamin E on brain tissue damage by electromagnetic radiation of cell phone in pregnant and fetal rats.
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Mitochondrial dysfunction and calcium deregulation by the RanBP9-cofilin pathway.
FASEB J.
PUBLISHED: 08-27-2013
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Mitochondrial dysfunction and synaptic damage are important features of Alzheimers disease (AD) associated with amyloid ? (A?) and tau. We reported previously that the scaffolding protein RanBP9, which is overall increased in brains of patients with AD and in mutant APP transgenic mice, simultaneously promotes A? generation and focal adhesion disruption by accelerating the endocytosis of APP and ?1-integrin, respectively. Moreover, RanBP9 induces neurodegeneration in vitro and in vivo and mediates A?-induced neurotoxicity. Here we show in primary hippocampal neurons that RanBP9 potentiates A?-induced reactive oxygen species (ROS) overproduction, apoptosis, and calcium deregulation. Analyses of calcium-handling measures demonstrate that RanBP9 selectively delays the clearance of cytosolic Ca(2+) mediated by the mitochondrial calcium uniporter through a process involving the translocation of cofilin into mitochondria and oxidative mechanisms. Further, RanBP9 retards the anterograde axonal transport of mitochondria in primary neurons and decreases synaptic mitochondrial activity in brain. These data indicate that RanBP9, cofilin, and A? mimic and potentiate each other to produce mitochondrial dysfunction, ROS overproduction, and calcium deregulation, which leads to neurodegenerative changes reminiscent of those seen in AD.-Roh. S.-E., Woo, J. A., Lakshmana, M. K., Uhlar, C., Ankala, V., Boggess, T., Liu, T., Hong, Y.-H., Mook-Jung, I., Kim, S. J., Kang, D. E. Mitochondrial dysfunction and calcium deregulation by the RanBP9-cofilin pathway.
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A model for family-based case-control studies of genetic imprinting and epistasis.
Brief. Bioinformatics
PUBLISHED: 07-24-2013
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Genetic imprinting, or called the parent-of-origin effect, has been recognized to play an important role in the formation and pathogenesis of human diseases. Although the epigenetic mechanisms that establish genetic imprinting have been a focus of many genetic studies, our knowledge about the number of imprinting genes and their chromosomal locations and interactions with other genes is still scarce, limiting precise inference of the genetic architecture of complex diseases. In this article, we present a statistical model for testing and estimating the effects of genetic imprinting on complex diseases using a commonly used case-control design with family structure. For each subject sampled from a case and control population, we not only genotype its own single nucleotide polymorphisms (SNPs) but also collect its parents genotypes. By tracing the transmission pattern of SNP alleles from parental to offspring generation, the model allows the characterization of genetic imprinting effects based on Pearson tests of a 2 × 2 contingency table. The model is expanded to test the interactions between imprinting effects and additive, dominant and epistatic effects in a complex web of genetic interactions. Statistical properties of the model are investigated, and its practical usefulness is validated by a real data analysis. The model will provide a useful tool for genome-wide association studies aimed to elucidate the picture of genetic control over complex human diseases.
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Exploring unsymmetrical dyads as efficient inhibitors against the insect ?-N-acetyl-d-hexosaminidase OfHex2.
Biochimie
PUBLISHED: 07-23-2013
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The GH20 ?-N-acetyl-d-hexosaminidase OfHex2 from the insect Ostrinia furnacalis (Guenée) is a target potential for eco-friendly pesticide development. Although carbohydrate-based inhibitors against ?-N-acetyl-d-hexosaminidases are widely studied, highly efficient, non-carbohydrate inhibitors are more attractive due to low cost and readily synthetic manner. Based on molecular modeling analysis of the catalytic domain of OfHex2, a series of novel naphthalimide-scaffold conjugated with a small aromatic moiety by an alkylamine spacer linker were designed and evaluated as efficiently competitive inhibitors against OfHex2. The most potent one containing naphthalimide and phenyl groups spanning by an N-alkylamine linker has a Ki value of 0.37 ?M, which is 6 fold lower than that of M-31850, the most potent non-carbohydrate inhibitor ever reported. The straightforward synthetic manners as well as the presumed binding model in this paper could be advantageous for further structural optimization for developing inhibitors against GH20 ?-N-acetyl-d-hexosaminidases.
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Development of an amplified luminescent proximity homogeneous assay for quantitative determination of hepatitis B surface antigen in human serum.
Clin. Chim. Acta
PUBLISHED: 07-11-2013
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Hepatitis B virus (HBV) poses a serious risk to human health and the hepatitis B surface antigen (HBsAg) is a popular biomarker in the diagnosis of HBV infection. A quantitative method with a high degree of accuracy, sensitivity and throughput is needed.
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Multichannel linear descriptors analysis for sustained attention-related electroencephalography.
Neuroreport
PUBLISHED: 06-27-2013
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This study investigated the differences in brain functional state between sustained attention and ignoring task conditions using the electroencephalography in association with sustained attention to response task (SART) performance. Multichannel electroencephalography data were obtained from 10 male healthy volunteers while performing the SART. Three multichannel linear descriptors, that is spatial complexity (?), field strength (?), and frequency of field changes (?), were applied to analyze three frequency bands (?, ?, and ?) for sustained attention and ignoring task conditions. The experimental results showed that participants had a significantly lower ? value in the ? and ? band in the SART state. The ? value was significantly higher in each frequency band of interest in almost all region of interest areas during SART performance. In addition, the ? value was significantly lower in the ? band and significantly higher in the ? band during the sustained attention condition. The results indicated that multichannel linear descriptors could show the differences in brain functions between sustained attention and ignoring task conditions, and might be used to evaluate disorders with an attentional dysfunction.
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In situ growth of metal-organic framework thin films with gas sensing and molecule storage properties.
Langmuir
PUBLISHED: 06-24-2013
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New porous metal-organic framework (MOF) films based on the flexible ligand 1,3,5-tris[4-(carboxyphenyl)oxamethyl]-2,4,6-trimethylbenzene (H3TBTC) were fabricated on ?-Al2O3 substrates under solvent thermal conditions. The factors affecting the fabrication of films, such as the temperature of pre-activation and the dosage of the reagents, were investigated. Tuning the subtle factors on film fabrications, a series of MOF thin films with different morphologies and grain sizes were prepared. The morphology and grain size of the films are monitored by scanning electron microscopy (SEM). X-ray diffraction (XRD) and attenuated total reflection infrared (ATR-IR) were also used to characterize the MOF films. The results indicate that the temperature of pre-activation and the dosage of the reagents are the key parameters during the process of film formation. The properties of the films, especially the sensing and sorption behavior, have been studied by an optical digital cameral and ultraviolet-visible (UV-vis) spectra. The evidence shows that the films are sensitive to small organic molecules, such as methanol and pyridine. Meanwhile, the films can adsorb small dye molecules. Thus, the films may have potential applications in either organic vapor sensing or storage of small dye molecules.
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Noise Effects In Various Quantitative Susceptibility Mapping Methods.
IEEE Trans Biomed Eng
PUBLISHED: 06-12-2013
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Various regularization methods have been proposed for single-orientation quantitative susceptibility mapping (QSM), which is an ill-posed magnetic field to susceptibility source inverse problem. Noise amplification, a major issue in inverse problems, manifests as streaking artifacts and quantification errors in QSM and has not been comparatively evaluated in these algorithms. In this paper, various QSM methods were systematically categorized for noise analysis. Six representative QSM methods were selected from four categories: two non-Bayesian methods with alteration or approximation of the dipole kernel to overcome the ill conditioning; four Bayesian methods using a general mathematical prior or a specific physical structure prior to select a unique solution, and using a data fidelity term with or without noise weighting. The effects of noise in these QSM methods were evaluated by reconstruction errors in simulation and image quality in 50 consecutive human subjects. Bayesian QSM methods with noise weighting consistently reduced root mean squared errors in numerical simulations and increased image quality scores in the human brain images, when compared to non-Bayesian methods and to corresponding Bayesian methods without noise weighting (p 0.001). In summary, noise effects in QSM can be reduced using Bayesian methods with proper noise weighting.
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[Effect of a desensitizing polishing paste on bonding strength of two self-etching adhesives to dentin].
Zhonghua Kou Qiang Yi Xue Za Zhi
PUBLISHED: 06-12-2013
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To evaluate the effect of an 8% arginine-CaCO3 containing desensitizing polishing paste on bonding strength of two self-etching adhesives to dentin.
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A rapid and sensitive method based on magnetic beads for the detection of hepatitis B virus surface antigen in human serum.
Luminescence
PUBLISHED: 06-06-2013
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Current clinically assays, such as enzyme-linked immunosorbent assay and chemiluminescence immunoassay, for hepatitis B surface antigen (HBsAg) are inferior in terms of either sensitivity and accuracy or rapid and high-throughput analysis. A novel assay based on magnetic beads and time-resolved fluoroimmunoassay was developed for the quantitative determination of HBsAg in human serum. HBsAg was captured using two types of anti-HBsAg monoclonal antibodies (B028, S015) immobilized on to magnetic beads and detected using europium-labeled anti-HBsAg polyclonal detection antibody. Finally, the assay yielded a high sensitivity (0.02?IU/mL) and a wide dynamic range (0.02-700?IU/mL) for HBsAg when performed under optimal conditions. Satisfactory accuracy, recovery and specificity were also demonstrated. The intra- and interassay coefficients of variation were 4.7-8.7% and 3.8-7.5%, respectively. The performance of this assay was further assessed against a well-established commercial chemiluminescence immunoassay kit with 399 clinical serum samples. It was revealed that the test results for the two methods were in good correlation (Y?=?1.182X - 0.017, R?=?0.989). In the current study, we demonstrated that this novel time-resolved fluoroimmunoassay could be used: as a highly sensitive, automated and high-throughput immunoassay for the diagnosis of acute or chronic hepatitis B virus infection; for the screening of blood or organ donors; and for the surveillance of persons at risk of acquiring or transmitting hepatitis B virus. Copyright © 2013 John Wiley & Sons, Ltd.
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Influence of vascular comorbidities and race on erectile dysfunction after prostate cancer radiotherapy.
J Sex Med
PUBLISHED: 06-06-2013
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Vascular comorbidities (VC) (hypertension, diabetes, and hyperlipidemia) are known factors related to erectile dysfunction (ED) in men. However, no data are yet available for the effects of VC on ED incidence after prostate cancer radiotherapy (XRT).
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Hematoma volume measurement in gradient echo MRI using quantitative susceptibility mapping.
Stroke
PUBLISHED: 05-23-2013
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A novel quantitative susceptibility mapping (QSM) processing technology has been developed to map tissue susceptibility property without blooming artifacts. We hypothesize that hematoma volume measurement on QSM is independent of imaging parameters, eliminating its echo time dependence on gradient echo MRI.
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An iterative spherical mean value method for background field removal in MRI.
Magn Reson Med
PUBLISHED: 05-22-2013
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The sophisticated harmonic artifact reduction for phase data (SHARP) method has been proposed for the removal of background field in MRI phase data. It relies on the spherical mean value (SMV) property of harmonic functions, and its accuracy depends on the radius of the sphere used for computing the SMV and truncation threshold needed for deconvolution. The goal of this study was to develop an alternative SMV-based background field removal method with reduced dependences on these parameters.
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Flow compensated quantitative susceptibility mapping for venous oxygenation imaging.
Magn Reson Med
PUBLISHED: 05-20-2013
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Venous blood oxygen saturation is an indicator of brain oxygen consumption and can be measured directly from quantitative susceptibility mapping (QSM) by deconvolving the MR phase signal. However, accurate estimation of the susceptibility of blood may be affected by flow induced phase in the presence of imaging gradient and the inhomogeneous susceptibility field gradient. The purpose of this study is to correct the flow induced error in QSM for improved venous oxygenation quantification.
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Magnetic particle-based time-resolved fluoroimmunoassay for the simultaneous determination of ?-fetoprotein and the free ?-subunit of human chorionic gonadotropin.
Analyst
PUBLISHED: 05-15-2013
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In this paper, a novel time-resolved fluoroimmunoassay (TRFIA) protocol using magnetic particles for the simultaneous determination of ?-fetoprotein (AFP) and the free ?-subunit of human chorionic gonadotropin (free ?-hCG) in human serum is described. The new approach uses magnetic particles as an immobilization matrix and means of separation, while the luminescent europium and samarium chelates are used as probes. The proposed method was evaluated via a single-step, sandwich-type TRFIA immunoassay of AFP and free ?-hCG as model analytes in serum. With the advantages of magnetic particles, the TRFIA immunoassay exhibited a wide dynamic range for AFP of 0.1-750 ng mL(-1), with a lower detection limit of 0.05 ng mL(-1). The dynamic range for free ?-hCG was 0.16-450 ng mL(-1), with a lower detection limit of 0.08 ng mL(-1). Satisfactory specificity, reproducibility, and recovery of the immunoassay were demonstrated. Good correlations were obtained in the analysis of 446 human serum samples between the proposed method and a commercial TRFIA kit. These results demonstrate the feasibility and potential of the new method as a rapid and highly sensitive immunoassay that could be developed into a platform for multi-analyte determinations in clinical practice.
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Improved subthalamic nucleus depiction with quantitative susceptibility mapping.
Radiology
PUBLISHED: 05-14-2013
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To assess quantitative susceptibility mapping (QSM) in the depiction of the subthalamic nucleus (STN) by using 3-T magnetic resonance (MR) imaging.
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Phosphatidylinositol 4-phosphate 5-kinase ? negatively regulates nerve growth factor-induced neurite outgrowth in PC12 cells.
Exp. Mol. Med.
PUBLISHED: 03-30-2013
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Neurite outgrowth, a cell differentiation process involving membrane morphological changes, is critical for neuronal network and development. The membrane lipid, phosphatidylinositol (PI) 4,5-bisphosphate (PIP2), is a key regulator of many important cell surface events of membrane signaling, trafficking and dynamics. This lipid is produced mainly by the type I PI 4-phosphate 5-kinase (PIP5K) family members. In this study, we addressed whether PIP5K?, an isoform of PIP5K, could have a role in neurite outgrowth induced by nerve growth factor (NGF). For this purpose, we knocked down PIP5K? in PC12 rat pheochromocytoma cells by stable expression of PIP5K? microRNA that significantly reduced PIP5K? expression and PIP2 level. Interestingly, NGF-induced neurite outgrowth was more prominent in PIP5K?-knockdown (KD) cells than in control cells. Conversely, add-back of PIP5K? into PIP5K? KD cells abrogated the effect of NGF on neurite outgrowth. NGF treatment activated PI 3-kinase (PI3K)/Akt pathway, which seemed to be associated with reactive oxygen species generation. Similar to the changes in neurite outgrowth, the PI3K/Akt activation by NGF was potentiated by PIP5K? KD, but was attenuated by the reintroduction of PIP5K?. Moreover, exogenously applied PIP2 to PIP5K? KD cells also suppressed Akt activation by NGF. Together, our results suggest that PIP5K? acts as a negative regulator of NGF-induced neurite outgrowth by inhibiting PI3K/Akt signaling pathway in PC12 cells.
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AlphaLISA for the determination of median levels of the free ? subunit of human chorionic gonadotropin in the serum of pregnant women.
J Immunoassay Immunochem
PUBLISHED: 03-30-2013
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Measurement of the free ? subunit of human chorionic gonadotropin (free ?-hCG) in serum is useful for prenatal screening. Concentrations of free ?-hCG vary in different races. Conventional assays used for such measurements have limitations. We applied the AlphaLISA to measure levels of free ?-hCG in maternal serum during 8-20 weeks of gestation in women from southern China. Two anti-free ?-hCG antibodies were used: one was coated on AlphaLISA acceptor beads and the one was biotinylated. The assay also contained donor beads coated with streptavidin. The AlphaLISA assay detection limit was 0.11 ng/mL, and the analytical range was 0.11-200 ng/mL. The intra- and interassay coefficients of variation were 1.32%-2.50% and 3.44%-5.45%, respectively. The correlation with commercial Eu(3+)-labeled free ?-HCG-TRFIA assay was good (y = 1.045x + 1.580, r(2) = 0.978). Median levels of free ?-hCG in maternal serum at 8-20 weeks gestation were higher in women from southern China compared with those reported in women from other countries. The AlphaLISA for free ?-HCG could become the assay of choice for applications in clinical diagnostics. The established median value of free ?-HCG is helpful in clinical diagnosis specific for southern Chinese women.
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[Correlation of single-cell gel electrophoresis and mitomycin C-induced chromosomal breakage for chromosomal instabiligy in children with Fanconi anemia].
Zhonghua Er Ke Za Zhi
PUBLISHED: 03-27-2013
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Fanconi anemia (FA) is characterized by bone marrow failure, congenital abnormalities and predisposition to neoplasia. Hypersensitivity of FA cells to the clastogenic effect of mitomycin C (MMC) provides a unique marker for the diagnosis before the beginning of hematological manifestations. The aim of this study was to evaluate the relationship between Single-Cell Gel Electrophoresis (SCGE) and mitomycin C-induced chromosomal breakage in children with FA.
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Construction of a polyhedral metal-organic framework via a flexible octacarboxylate ligand for gas adsorption and separation.
Inorg Chem
PUBLISHED: 03-07-2013
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A flexible octacarboxylate ligand, tetrakis[(3,5-dicarboxyphenyl)oxamethyl]methane (H8X), has been used to construct a highly porous metal-organic framework (In2X)(Me2NH2)2(DMF)9(H2O)5 (1), which is comprised of octahedral and cuboctahedral cages and shows a rare (4,8)-connected scu topology. Gas adsorption studies of N2, H2 on the actived 1 at 77 K reveal a Langmuir surface area of 1707 m(2) g(-1), a BET surface area of 1555 m(2) g(-1), a total pore volume of 0.62 cm(3) g(-1), and a H2 uptake of 1.49 wt % at 1 bar and 3.05 wt % at 16 bar. CO2, CH4, and N2 adsorption studies at 195, 273, 285, and 298 K and also ideal adsorbed solution theory (IAST) calculations demonstrate that 1 has high selectivites of CO2 over CH4 and N2. The resulting framework represents a MOF with the highest gas uptakes and gas selectivities (CO2 over CH4 and N2) constructed by flexible ligands.
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What is Visualize?

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

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

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.