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Find video protocols related to scientific articles indexed in Pubmed.
Self-assembly behavior of a linear-star supramolecular amphiphile based on host-guest complexation.
Langmuir
PUBLISHED: 10-24-2014
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A star polymer, ?-cyclodextrin-poly(l-lactide) (?-CD-PLLA), and a linear polymer, azobenzene-poly(ethylene glycol) (Azo-PEG), could self-assemble into a supramolecular amphiphilic copolymer (?-CD-PLLA@Azo-PEG) based on the host-guest interaction between ?-CD and azobenzene moieties. This linear-star supramolecular amphiphilic copolymer further self-assembled into a variety of morphologies, including sphere-like micelle, carambola-like micelle, naan-like micelle, shuttle-like lamellae, tube-like fiber, and random curled-up lamellae, by tuning the length of hydrophilic or hydrophobic chains. The variation of morphology was closely related to the topological structure and block ratio of the supramolecular amphiphiles. These self-assembly structures could disassemble upon an ultraviolet (UV) light irradiation.
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Stoichiometry and novel gating mechanism within the cystic fibrosis transmembrane conductance regulator channel.
Exp. Physiol.
PUBLISHED: 10-16-2014
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Despite its fundamental importance to the molecular mechanism underlying cystic fibrosis, many details of the structural basis for the cystic fibrosis transmembrane conductance regulator (CFTR) remain unknown. In addition, the possible interactions among the CFTR proteins have not been clearly demonstrated. In order to identify whether the CFTR channel pore is formed as a monomer or a multimer, we analysed the single-channel properties in patches of cell membrane that coexpressed selected CFTR mutants having significantly different single-channel properties. No hybrid channel opening patterns were observed. We therefore propose that the CFTR channel pore is indeed composed of a monomer. However, we also observed that coexisting CFTR monomers in the cell membrane facilitated the activation of individual CFTR channels. The functional upregulation of this CFTR channel opening probability and the different gating behaviour suggest dynamic conformational changes among the interacting CFTR proteins within the multimeric CFTR complex. Our findings regarding the CFTR monomer channel pore and the novel synergistic gating behaviour within the CFTR channel complex will help to resolve the remaining contradictions among previous studies regarding whether CFTR is a monomer or a multimer.
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Multi-boundary cardiac data visualization based on multidimensional transfer function with ray distance.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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A crucial role during the implementation of volume visualization is to identify the optimal transfer function, since the vital information and structure can be highlighted and revealed. The boundary of the volume is shared by respective portion of the two materials formed out of it, which causes undesirable thickening and ambiguity of the boundary explored via traditional LH (Low and High) histogram. To address this issue, initially a modified LH histogram construction method is introduced to intuitively and conveniently visualize cardiac volume for user interaction. Subsequently, the f-LH histogram is presented to further identify and visualize each portion of the boundary accurately. An appropriate multidimensional transfer function generation is proposed by using variables in f-LH space and spatial information, for visualizing the multi-boundary cardiac volume data.
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EUS assisted transmural cholecystogastrostomy fistula creation as a bridge for endoscopic internal gallbladder therapy using a novel fully covered metal stent.
BMC Gastroenterol
PUBLISHED: 09-16-2014
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Laparoscopic cholecystectomy (LC) has become the "gold standard" for treating symptomatic gallstones. Innovative methods, such as a scarless therapeutic procedure through a natural orifice are being introduced, and include transgastric or transcolonic endoscopic cholecystectomy. However, before clinical implementation, instruments still need modification, and a more convenient treatment is still needed. The aim of this study was to evaluate the feasibility of endoscopic internal gallbladder therapy such as cholecystolithotomy in an animal survival model.
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Aspirin Enhances Protective Effect of Fish Oil against Thrombosis and Injury-induced Vascular Remodeling.
Br. J. Pharmacol.
PUBLISHED: 09-15-2014
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Although aspirin (acetylsalicylic acid, ASA) is commonly used to prevent ischemic events in patients with coronary artery disease (CAD), including those undergoing percutaneous coronary intervention (PCI), many patients fail to respond to ASA treatment. Dietary fish oil (FO),containing ?3 polyunsaturated fatty acids (PUFAs), has anti-inflammatory and cardio-protective properties, such as lowering cholesterol and modulating platelet activity. The objective of the present study is to investigate the potential additional effects of ASA and FO on platelet activity and vascular response to injury.
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Systemic C3 modulates CD8+ T cell contraction after Listeria monocytogenes infection.
J. Immunol.
PUBLISHED: 09-03-2014
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Ag-specific CD8(+) T cell contraction (contraction), which occurs after the resolution of infection, is critical for homeostasis of the immune system. Although complement components regulate the primary CD8(+) T cell response, there is insufficient evidence supporting their role in regulating contraction and memory. In this study, we show that C3-deficient (C3(-/-)) mice exhibited significantly less CD8(+) T cell contraction than did wild-type mice postinfection with recombinant Listeria monocytogenes expressing OVA. Kinetic analyses also revealed decreased contraction in mice treated with cobra venom factor to deplete C3, which was consistent with the results in C3(-/-) recipient mice transplanted with bone marrow cells from the same donors as wild-type recipient mice. The phenotypes of memory cells generated by C3(-/-) mice were not altered compared with those of wild-type mice. Further, C5aR signaling downstream of C3 was not involved in the regulation of contraction. Moreover, the regulation of contraction by C3 may be independent of the duration of antigenic stimulation or the functional avidity of effector CD8(+) T cells. However, reduced contraction in C3(-/-) mice was accompanied by a decrease in the proportion of KLRG-1(hi) (killer-cell lectin-like receptor G1) CD127(lo) short-lived effector cells at the peak of the response and correlated with a reduction in the levels of inflammatory cytokines, such as IL-12 and IFN-?, produced early postinfection. These results provide new insights into the role of systemic C3 in regulating contraction following intracellular bacterial infection and may help to develop vaccines that are more effective.
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Research on a novel two-stage direct current hybrid circuit breaker.
Rev Sci Instrum
PUBLISHED: 09-01-2014
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The DC hybrid circuit breaker based on high-speed switch (HSS) and parallel connected capacitor has been widely applied in the fault current breaking of DC system. However, when the current is commutated from HSS to the capacitor according to single-stage operation, the capacitor has to absorb a large amount of energy stored in the system inductance within very short time. Meanwhile, a high over-voltage rate of rise is especially prone to be produced between the contacts of HSS, which will lead to a failed breaking. As a result, a novel DC hybrid circuit breaker based on the two-stage operation is proposed and analyzed in this paper. By controlling the thyristors in the commutation branches, the fault current is fast commutated into the capacitor, which can not only realize the arcless open of HSS, but also decrease the over-voltage rate of rise significantly in comparison to the traditional single-stage operation. The simulation model of fault current breaking under different conditions in 10 kV medium voltage DC system is constructed. The simulated over-voltages of single-stage and two-stage operations in the case of fault current breaking are compared and analyzed. Finally, the fault current breaking test in the two-stage operation is investigated experimentally, which validates the feasibility and effectiveness of the simulation model well.
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Nanoscale three-dimensional imaging of the human myocyte.
J. Struct. Biol.
PUBLISHED: 08-23-2014
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The ventricular human myocyte is spatially organized for optimal ATP and Ca(2+) delivery to sarcomeric myosin and ionic pumps during every excitation-contraction cycle. Comprehension of three-dimensional geometry of the tightly packed ultrastructure has been derived from discontinuous two-dimensional images, but has never been precisely reconstructed or analyzed in human myocardium. Using a focused ion beam scanning electron microscope, we created nanoscale resolution serial images to quantify the three-dimensional ultrastructure of a human left ventricular myocyte. Transverse tubules (t-tubule), lipid droplets, A-bands, and mitochondria occupy 1.8, 1.9, 10.8, and 27.9% of the myocyte volume, respectively. The complex t-tubule system has a small tortuosity (1.04±0.01), and is composed of long transverse segments with diameters of 317±24nm and short branches. Our data indicates that lipid droplets located well beneath the sarcolemma are proximal to t-tubules, where 59% (13 of 22) of lipid droplet centroids are within 0.50?m of a t-tubule. This spatial association could have an important implication in the development and treatment of heart failure because it connects two independently known pathophysiological alterations, a substrate switch from fatty acids to glucose and t-tubular derangement.
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[The value of electromyography in differentiating intramedullary tumor from inflammatory demyelinating disease of cervical region].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 08-23-2014
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To investigate the value of needle electromyography (EMG) in differentiating intramedullary tumor from inflammatory demyelinating disease of cervical region.
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Assessment of type 2 diabetes risk conferred by SNPs rs2241766 and rs1501299 in the ADIPOQ gene, a case/control study combined with meta-analyses.
Mol. Cell. Endocrinol.
PUBLISHED: 08-15-2014
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We conducted a case/control study to assess the impact of two SNPs, rs2241766 and rs1501299 within the ADIPOQ gene, on type 2 diabetes (T2D) susceptibility in a Chinese Han dataset (741 cases and 902 controls). SNP rs2241766 was found significantly associated with T2D risk in the additive model, dominant model and recessive model. A marginal association was detected for SNP rs1501299 in the additive model and recessive model after Bonferroni correction, and haplotype analysis provided additional evidence supporting the association between these two SNPs and T2D risk. A meta-analysis including 29 published datasets along with current dataset was next carried out to further confirm the association. In consistent with our case/control results, rs2241766 showed a significant association with T2D in the dominant model and additive model, and the association between rs1501299 and T2D was also characterized in the homozygote model, dominant model, recessive model, and additive model. Of note, the association became much stronger in East Asians after exclusion of ethnic stratification. Together, our data support that the rs2241766 and rs1501299 polymorphisms within the ADIPOQ gene confer genetic susceptibility for type 2 diabetes, especially in the Chinese Han population.
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Equine Viperin Restricts Equine Infectious Anemia Virus Replication by Inhibiting the Production and/or Release of Viral Gag, Env, and Receptor via Distortion of the Endoplasmic Reticulum.
J. Virol.
PUBLISHED: 08-13-2014
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Viperin is an endoplasmic reticulum (ER)-associated multifunctional protein that regulates virus replication and possesses broad antiviral activity. In many cases, viperin interferes with the trafficking and budding of viral structural proteins by distorting the membrane transportation system. The lentivirus equine infectious anemia virus (EIAV) has been studied extensively. In this study, we examined the restrictive effect of equine viperin (eViperin) on EIAV replication and investigated the possible molecular basis of this restriction to obtain insights into the effect of this cellular factor on retroviruses. We demonstrated that EIAV infection of primary equine monocyte-derived macrophages (eMDMs) upregulated the expression of eViperin. The overexpression of eViperin significantly inhibited the replication of EIAV in eMDMs, and knockdown of eViperin transcription enhanced the replication of EIAV in eMDMs by approximately 45.8%. Further experiments indicated that eViperin restricts EIAV at multiple steps of viral replication. The overexpression of eViperin inhibited EIAV Gag release. Both the ?-helix domain and radical S-adenosylmethionine (SAM) domain were required for this activity. However, the essential motifs in SAM were different from those reported for the inhibition of HIV-1 Gag by human viperin. Furthermore, eViperin disrupted the synthesis of both EIAV Env and receptor, which consequently inhibited viral production and entry, respectively, and this disruption was dependent on the eViperin ?-helix domain. Using immunofluorescence assays and electron microscopy, we demonstrated that the ?-helix domain is responsible for the distortion of the endoplasmic reticulum (ER). Finally, EIAV did not exhibit counteracting eViperin at the protein level.
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Genome-wide characterization of light-regulated genes in Neurospora crassa.
G3 (Bethesda)
PUBLISHED: 07-24-2014
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The filamentous fungus Neurospora crassa responds to light in complex ways. To thoroughly study the transcriptional response of this organism to light, RNA-seq was used to analyze capped and polyadenylated mRNA prepared from mycelium grown for 24 hr in the dark and then exposed to light for 0 (control) 15, 60, 120, and 240 min. More than three-quarters of all defined protein coding genes (79%) were expressed in these cells. The increased sensitivity of RNA-seq compared with previous microarray studies revealed that the RNA levels for 31% of expressed genes were affected two-fold or more by exposure to light. Additionally, a large class of mRNAs, enriched for transcripts specifying products involved in rRNA metabolism, showed decreased expression in response to light, indicating a heretofore undocumented effect of light on this pathway. Based on measured changes in mRNA levels, light generally increases cellular metabolism and at the same time causes significant oxidative stress to the organism. To deal with this stress, protective photopigments are made, antioxidants are produced, and genes involved in ribosome biogenesis are transiently repressed.
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[Effects of microRNA-21 on the myocardial cell apoptosis induced by ischemia and hypoxia in rat].
Zhonghua Shao Shang Za Zhi
PUBLISHED: 07-04-2014
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To explore the effects of microRNA-21 on apoptosis of myocardial cell of rats as induced by ischemia and hypoxia, and to analyze the underlying mechanisms.
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Is Interactional Dissynchrony a Clue to Deception? Insights From Automated Analysis of Nonverbal Visual Cues.
IEEE Trans Cybern
PUBLISHED: 07-03-2014
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Detecting deception in interpersonal dialog is challenging since deceivers take advantage of the give-and-take of interaction to adapt to any sign of skepticism in an interlocutor's verbal and nonverbal feedback. Human detection accuracy is poor, often with no better than chance performance. In this investigation, we consider whether automated methods can produce better results and if emphasizing the possible disruption in interactional synchrony can signal whether an interactant is truthful or deceptive. We propose a data-driven and unobtrusive framework using visual cues that consists of face tracking, head movement detection, facial expression recognition, and interactional synchrony estimation. Analysis were conducted on 242 video samples from an experiment in which deceivers and truth-tellers interacted with professional interviewers either face-to-face or through computer mediation. Results revealed that the framework is able to automatically track head movements and expressions of both interlocutors to extract normalized meaningful synchrony features and to learn classification models for deception recognition. Further experiments show that these features reliably capture interactional synchrony and efficiently discriminate deception from truth.
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[Assessment of HER2 gene amplification in breast cancer: a comparison of dual-color in-situ hybridization and fluorescence in-situ hybridization].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 06-12-2014
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To compare dual-color in-situ hybridization (DISH) with fluorescence in situ hybridization(FISH) in evaluating the human HER2 gene status in invasive breast cancer.
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Intercellular adhesion molecule-1 inhibits osteogenic differentiation of mesenchymal stem cells and impairs bio-scaffold-mediated bone regeneration in vivo.
Tissue Eng Part A
PUBLISHED: 06-05-2014
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Mesenchymal stem cell (MSC) loaded bio-scaffold transplantation is a promising therapeutic approach for bone regeneration and repair. However, growing evidence shows that pro-inflammatory mediators from injured tissues suppress osteogenic differentiation and impair bone formation. To improve MSC-based bone regeneration, it is important to understand the mechanism of inflammation mediated osteogenic suppression. In the present study, we found that synovial fluid from rheumatoid arthritis patients and pro-inflammatory cytokines including interleukin-1?, interleukin-1?, and tumor necrosis factor ?, stimulated intercellular adhesion molecule-1(ICAM-1) expression and impaired osteogenic differentiation of MSCs. Interestingly, overexpression of ICAM-1 in MSCs using a genetic approach also inhibited osteogenesis. In contrast, ICAM-1 knockdown significantly reversed the osteogenic suppression. In addition, after transplanting a traceable MSC-poly(lactic-co-glycolic acid) construct in rat calvarial defects, we found that ICAM-1 suppressed MSC osteogenic differentiation and matrix mineralization in vivo. Mechanistically, we found that ICAM-1 enhances MSC proliferation but causes stem cell marker loss. Furthermore, overexpression of ICAM-1 stably activated the MAPK and NF-?B pathways but suppressed the PI3K/AKT pathway in MSCs. More importantly, specific inhibition of the ERK/MAPK and NF-?B pathways or activation of the PI3K/AKT pathway partially rescued osteogenic differentiation, while inhibition of the p38/MAPK and PI3K/AKT pathway caused more serious osteogenic suppression. In summary, our findings reveal a novel function of ICAM-1 in osteogenesis and suggest a new molecular target to improve bone regeneration and repair in inflammatory microenvironments.
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Topical application of rapamycin ointment ameliorates Dermatophagoides farina body extract-induced atopic dermatitis in NC/Nga mice.
Exp. Dermatol.
PUBLISHED: 06-03-2014
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Atopic dermatitis (AD), a chronic inflammatory skin disease characterized by relapsing eczema and intense prurigo, requires effective and safe pharmacological therapy. Recently, rapamycin, an mTOR (mammalian target of rapamycin) inhibitor, has been reported to play a critical role in immune responses and has emerged as an effective immunosuppressive drug. In this study, we assessed whether inhibition of mTOR signalling could suppress dermatitis in mice. Rapamycin was topically applied to inflamed skin in a murine AD model that was developed by repeated topical application of Dermatophagoides farina body (Dfb) extract antigen twice weekly for 7 weeks in NC/Nga mice. The efficacy of topical rapamycin treatment was evaluated immunologically and serologically. Topical application of rapamycin reduced inflammatory cell infiltration in the dermis, alleviated the increase of serum IgE levels and resulted in a significant reduction in clinical skin condition score and marked improvement of histological findings. In addition, increased mTOR phosphorylation in the lesional skin was observed in our murine AD model. Topical application of rapamycin ointment inhibited Dfb antigen-induced dermatitis in NC/Nga mice, promising a new therapy for atopic dermatitis.
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Electrical Stimulation of Dorsal Root Entry Zone Attenuates Wide-Dynamic-Range Neuronal Activity in Rats.
Neuromodulation
PUBLISHED: 06-02-2014
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Recent clinical studies suggest that neurostimulation at the dorsal root entry zone (DREZ) may alleviate neuropathic pain. However, the mechanisms of action for this therapeutic effect are unclear. Here, we examined whether DREZ stimulation inhibits spinal wide-dynamic-range (WDR) neuronal activity in nerve-injured rats.
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[Evaluation of serum creatinine level in amyotrophic lateral sclerosis patients].
Zhonghua Nei Ke Za Zhi
PUBLISHED: 05-27-2014
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To investigate the serum creatinine (SCr) level in patients with sporadic amyotrophic lateral sclerosis (sALS) and to explore the relationship between the SCr level and the clinical characteristics.
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Adding a Sexual Dysfunction Domain to UPOINT System Improves Association With Symptoms in Women With Interstitial Cystitis and Bladder Pain Syndrome.
Urology
PUBLISHED: 05-16-2014
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To examine whether adding a sexual dysfunction domain to urinary, psychosocial, organ specific, infection, neurologic or systemic, and tenderness (UPOINT) system improves the association with interstitial cystitis and bladder pain syndrome (IC-BPS) symptom severity due to a high prevalence of sexual dysfunction in women.
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Identifying early urinary metabolic changes with long-term environmental exposure to cadmium by mass-spectrometry-based metabolomics.
Environ. Sci. Technol.
PUBLISHED: 05-16-2014
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Cadmium (Cd) is a common environmental pollutant, and urinary Cd (UCd) is generally used as a marker of exposure; however, our understanding on the related urinary metabolic changes caused by Cd exposure is still not clear. In this study, we applied a mass-spectrometry-based metabolomic approach to assess the urinary metabolic changes in human with long-term environmental Cd exposure, aimed to identify early biomarkers to assess Cd nephrotoxicity. Urine samples from 94 female never smokers aged 44-70 with UCd in the range of 0.20-68.67 ?g/L were analyzed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-ToF-MS) and gas chromatography-mass spectrometry (GC-MS). It was found that metabolites related to amino acid metabolism (L-glutamine, L-cystine, L-tyrosine, N-methyl-L-histidine, L-histidinol, taurine, phenylacetylglutamine, hippurate, and pyroglutamic acid), galactose metabolism (D-galactose and myo-inositol), purine metabolism (xanthine, urea, and deoxyadenosine monophosphate), creatine pathway (creatine and creatinine), and steroid hormone biosynthesis (17-?-hydroxyprogesterone, tetrahydrocortisone, estrone, and corticosterone) were significantly higher among those with a UCd level higher than 5 ?g/L. Moreover, we noticed that the level of N-methyl-L-histidine had already started to elevate among individuals with a UCd concentration of ?2 ?g/L. The overall findings illustrate that metabolomics offer a useful approach for revealing metabolic changes as a result of Cd exposure.
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Environmentally friendly method for the determination of acrylamide and trimethylolpropane in paper packaging materials by liquid chromatography with tandem mass spectrometry.
J Sep Sci
PUBLISHED: 05-08-2014
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A simple, rapid, and environmentally friendly method was developed for the determination of acrylamide and trimethylolpropane in paper packaging materials. No organic solvent was used and the matrix effect was investigated. The extract was directly analyzed by liquid chromatography with tandem mass chromatography for quantification and confirmation. The chromatographic separations were performed on a ZORBAX HILIC Plus (2.1 mm × 150 mm, 3?m; Agilent, USA) column with only one mobile phase (100% water). Calibration curves for acrylamide and trimethylopropane were achieved with concentrations ranging from 0.4 to 20 mg/kg and the corresponding r(2) values were 0.998 and 0.999, respectively. The recoveries were >85% with relative standard deviations <10%. The validated method was applied to the analysis of 50 real samples, and positive results were obtained for 30 samples. The result indicated that trimethylolpropane is associated with inks and printing activity and acrylamide is widely used as a papermaking additive in many paper packages. The concentrations of acrylamide and trimethylolpropane ranged from 0.41 to 7.5 and 0.50 to 8.8 mg/kg, respectively. The results of this study revealed that this method could be used accurately and precisely.
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Influence of substrate on electricity generation of Shewanella loihica PV-4 in microbial fuel cells.
Microb. Cell Fact.
PUBLISHED: 05-07-2014
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The substrate, serving as carbon and energy source, is one of the major factors affecting the performance of microbial fuel cells (MFCs). We utilized BIOLOG system to rapidly screen substrates for electricigens, and further evaluated influence of these substrates on electricity generation of Shewanella loihica PV-4 in MFCs.
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Nasopharyngeal cancer-specific therapy based on fusion peptide-functionalized lipid nanoparticles.
ACS Nano
PUBLISHED: 05-01-2014
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Current treatment of advanced-stage nasopharyngeal carcinoma (NPC) is not satisfactory. Targeted therapies offer hope for extending survival. Here, we developed simple, robust, and NPC-specific therapeutic lipid nanoparticles based on a fusion peptide, ?-NTP, made up of an amphipathic ?-helical peptide (?-peptide) linked to an NPC-specific therapeutic peptide (NTP). We found that ?-NTP not only retained the sub-30 nm nanostructure-controlling ability of the ?-peptide but also displayed the enhanced NPC-targeting ability of the NTP, in which the ?-peptide accelerated the uptake of the NTP by NPC cells, with a 4.8-fold increase. Following uptake, ?-NTP-based lipid nanoparticles (?-NTP-LNs) exerted coordinated cytotoxicity by inducing cell death via apoptosis and autophagy. In vivo and ex vivo optical imaging data showed that systemically administered ?-NTP-LNs efficiently accumulated in the NPC xenograft tumor and displayed high contrast between tumor and normal tissues, which was further confirmed by flow cytometry that there had been a 13-fold uptake difference between tumor cells and hepatocytes. More importantly, the therapeutic efficacy of ?-NTP-LNs was specific to NPC xenograft formed with 5-8F cells but not to fibrosarcoma xenograft formed with HT1080 cells in vivo. The growth of 5-8F tumors was significantly inhibited by ?-NTP-LNs, with more than 85% inhibition relative to control groups (e.g., ?-NTP and PBS treatment). In a lung metastasis model of NPC, survival was significantly improved by ?-NTP-LN treatment. In a word, these excellent properties of ?-NTP-LNs worked in sync and synergistically, maximizing the therapeutic efficacy of ?-NTP-LNs against NPC and its metastasis.
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POSS dendrimers constructed from a 1 ? 7 branching monomer.
Chem. Commun. (Camb.)
PUBLISHED: 04-30-2014
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Here, we demonstrate the first known approach to create G1 and G2 POSS dendrimers with 9 and 65 POSS units, and 56 and 392 terminal vinyl groups from a 1 ? 7 branching monomer in only one and three steps.
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[Analysis of refractive status after cataract surgery in age-related cataract patients with shallow anterior chamber].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 04-17-2014
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To evaluate the characteristics of postoperative refractive status in age-related cataract patients with shallow anterior chamber and the correlation between pre-operative anterior chamber depth and postoperativerefractive status.
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[Efficacy of noninvasive ventilation on in-hospital mortality in patients with acute cardiogenic pulmonary edema: a meta-analysis].
Zhonghua Xin Xue Guan Bing Za Zhi
PUBLISHED: 04-17-2014
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To evaluate the efficacy of noninvasive ventilation on in-hospital mortality in adult patients with acute cardiogenic pulmonary edema (ACPE) .
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Complement factor I polymorphism is not associated with neovascular age-related macular degeneration and polypoidal choroidal vasculopathy in a chinese population.
Ophthalmologica
PUBLISHED: 04-08-2014
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To identify the associations of the two complement factor I (CFI) polymorphisms rs10033900 and rs2285714 with risk of neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) in a Chinese case-control study.
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Different hereditary contribution of the CFH gene between polypoidal choroidal vasculopathy and age-related macular degeneration in Chinese Han people.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 04-03-2014
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To investigate whether 11 variants in complement factor H gene contributed differently in patients with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) of Chinese descent.
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Bio-cathode materials evaluation and configuration optimization for power output of vertical subsurface flow constructed wetland - microbial fuel cell systems.
Bioresour. Technol.
PUBLISHED: 03-31-2014
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To optimize the performance of a vertical subsurface flow constructed wetland-microbial fuel cell (CW-MFC), studies of bio-cathode materials and reactor configurations were carried out. Three commonly used bio-cathode materials including stainless steel mesh (SSM), carbon cloth (CC) and granular activated carbon (GAC) were compared and evaluated. GAC-SSM bio-cathode achieved the highest maximum power density of 55.05 mWm(-2), and it was most suitable for CW-MFCs application because of its large surface area and helpful capillary water absorption. Two types of CW-MFCs with roots were constructed, one was placed in the anode and the other was placed in the cathode. Both planted CW-MFCs obtained higher power output than non-planted CW-MFC. Periodic voltage fluctuations of planted CW-MFCs were caused by light/dark cycles, and the influent substrate concentration significantly affected the amplitude of oscillation. The coulombic efficiencies of CW-MFCs decreased greatly with the increase of the influent substrate concentration.
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High-mobility group box 1 exacerbates CCl?-induced acute liver injury in mice.
Clin. Immunol.
PUBLISHED: 03-28-2014
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High-mobility group box 1 (HMGB1) is a nuclear factor that can also serve as an imflammatory mediator once released into extracellular milieu. Therefore, HMGB1 has been recognized to play a pivotal role in inflammatory diseases such as sepsis, acute lung injury, ischemia reperfusion injury and type 1 diabetes. Nevertheless, its impact on carbon tetrachloride (CCl4)-induced hepatic injury is yet to be elucidated. In the present report, we demonstrated evidence indicating that high levels of HMGB1 were not only present in the necrotic area of liver but also in the serum after CCl4 challenge. In line with these observations, administration of exogenous recombinant HMGB1 exacerbated CCl4-induced hepatic injury, while HMGB1 blocking antibody provided protection for mice against CCl4-induced acute liver injury as evidenced by the decrease of serum transaminase and reduction of hepatic tissues necrosis. Mechanistic studies revealed that blockade of HMGB1 attenuated CCl4-induced MDA accumulation along with improved SOD and GSH activity. Treatment of mice with HMGB1 neutralizing antibody also significantly inhibited the production of proinflammatory mediators TNF-? and IL-6 along with attenuated HMGB1 expression and its extracellular release. Together, our data suggest an essential role for HMGB1 in CCl4-induced acute liver injury, while HMGB1 neutralizing antibody could be served as an effective regimen for preventing CCl4-induced acute liver injury.
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ABCA1 rs1883025 polymorphism shows no association with neovascular age-related macular degeneration or polypoidal choroidal vasculopathy in a Northern Chinese population.
Ophthalmic Res.
PUBLISHED: 03-28-2014
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To analyze the association between ABCA1 rs1883025 variants with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) in a northern Chinese population.
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Periostin accelerates human malignant melanoma progression by modifying the melanoma microenvironment.
Pigment Cell Melanoma Res
PUBLISHED: 03-24-2014
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Given no reliable therapy for advanced malignant melanoma, it is important to elucidate the molecular mechanisms underlying the disease progression. Using a quantitative proteomics approach, the 'isobaric tags for relative and absolute quantitation (iTRAQ)' method, we identified that the extracellular matrix protein, periostin (POSTN), was highly expressed in invasive melanoma compared with normal skin. An immunohistochemical analysis showed that POSTN was expressed in all invasive melanoma (n = 20) and metastatic lymph node (n = 5) tissue samples, notably restricted in their stroma. In terms of the intercellular regulation of POSTN, we found that there was upregulation of POSTN when melanoma cells and normal human dermal fibroblasts (NHDFs) were cocultured, with restricted expression of TGF-?1 and TGF-?3. In a functional analyses, recombinant and NHDF-derived POSTN significantly accelerated melanoma cell proliferation via the integrin/mitogen-activated protein kinase (MAPK) signaling pathway in vitro. The size of implanted melanoma tumors was significantly suppressed in POSTN/Rag2 double knockout mice compared with Rag2 knock-out mice. These results indicate that NHDF-derived POSTN accelerates melanoma progression and might be a promising therapeutic target for malignant melanoma.
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Investigation of molecular diagnosis in Chinese patients with myotonic dystrophy type 1.
Chin. Med. J.
PUBLISHED: 03-14-2014
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Myotonic dystrophy type 1 (DM1) is an autosomal dominant multisystem disease caused by abnormal expansion of cytosine-thymine-guanine (CTG) repeats in the myotonic dystrophy protein kinase gene. The clinical manifestations of DM1 are multisystemic and highly variable, and the unstable nature of CTG expansion causes wide genotypic and phenotypic presentations, which make molecular methods essential for the diagnosis. So far, very few studies about molecular diagnosis in Chinese patients with DM1 have been reported. Therefore, we carried out a study using two different methods in molecular diagnosis to verify the validity in detecting CTG expansion in Chinese patients showing DM signs.
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C5a/C5aR pathway is essential for the pathogenesis of murine viral fulminant hepatitis by way of potentiating Fgl2/fibroleukin expression.
Hepatology
PUBLISHED: 03-03-2014
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Viral fulminant hepatitis (FH) remains a serious clinical problem with very high mortality. Lacking understanding of FH pathogenesis has in essence hindered efficient clinical treatment. Inferring from a correlation observed between the genetic differences in the complement component 5 (C5) and the susceptibility of mouse strains to murine hepatitis virus strain-3 (MHV-3) infections, we propose that excessive complement activation plays a critical role in the development of FH. We show that MHV-3 infection causes massive complement activation, along with a rapid increase in serum C5a levels and quick development of FH in susceptible strains. Mice deficient in the C5a receptor (C5aR) or the susceptible strains treated with C5aR antagonists (C5aRa) exhibit significant attenuation of the disease, accompanied by a remarkable reduction of hepatic fibrinogen-like protein 2 (Fgl2), a hallmark protein that causes necrosis of infected livers. In accordance, biopsy of FH patients shows a dramatic increase of Fgl2 expression, which correlates with C5aR up-regulation in the liver. In vitro C5a administration accelerates MHV-3-induced Fgl2 secretion by macrophages. Furthermore, inhibiting ERK1/2 and p38 efficiently blocks C5a-mediated Fgl2 production during viral infections.
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Electrophysiological and clinical examination of polymyositis: a retrospective analysis.
Am. J. Med. Sci.
PUBLISHED: 02-22-2014
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We retrospectively analyzed electromyogram (EMG), laboratory and clinical data of 93 patients with polymyositis (PM) to help improve early diagnostic accuracy.
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Activation of MrgC receptor inhibits N-type calcium channels in small-diameter primary sensory neurons in mice.
Pain
PUBLISHED: 02-21-2014
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Mas-related G-protein-coupled receptor subtype C (mouse MrgC11 and rat rMrgC), expressed specifically in small-diameter primary sensory neurons, may constitute a novel pain inhibitory mechanism. We have shown previously that intrathecal administration of MrgC-selective agonists can strongly attenuate persistent pain in various animal models. However, the underlying mechanisms for MrgC agonist-induced analgesia remain elusive. Here, we conducted patch-clamp recordings to test the effect of MrgC agonists on high-voltage-activated (HVA) calcium current in small-diameter dorsal root ganglion (DRG) neurons. Using pharmacological approaches, we show for the first time that an MrgC agonist (JHU58) selectively and dose-dependently inhibits N-type, but not L- or P/Q-type, HVA calcium channels in mouse DRG neurons. Activation of HVA calcium channels is important to neurotransmitter release and synaptic transmission. Patch-clamp recordings in spinal cord slices showed that JHU58 attenuated the evoked excitatory postsynaptic currents in substantia gelatinosa (SG) neurons in wild-type mice, but not in Mrg knockout mice, after peripheral nerve injury. These findings indicate that activation of endogenously expressed MrgC receptors at central terminals of primary sensory fibers may decrease peripheral excitatory inputs onto SG neurons. Together, these results suggest potential cellular and molecular mechanisms that may contribute to intrathecal MrgC agonist-induced analgesia. Because MrgC shares substantial genetic homogeneity with human MrgX1, our findings may suggest a rationale for developing intrathecally delivered MrgX1 receptor agonists to treat pathological pain in humans and provide critical insight regarding potential mechanisms that may underlie its analgesic effects.
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Post-stroke pain hypersensitivity induced by experimental thalamic hemorrhage in rats is region-specific and demonstrates limited efficacy of gabapentin.
Neurosci Bull
PUBLISHED: 02-20-2014
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Intractable central post-stroke pain (CPSP) is one of the most common sequelae of stroke, but has been inadequately studied to date. In this study, we first determined the relationship between the lesion site and changes in mechanical or thermal pain sensitivity in a rat CPSP model with experimental thalamic hemorrhage produced by unilateral intra-thalamic collagenase IV (ITC) injection. Then, we evaluated the efficacy of gabapentin (GBP), an anticonvulsant that binds the voltage-gated Ca(2+) channel ?2? and a commonly used anti-neuropathic pain medication. Histological case-by-case analysis showed that only lesions confined to the medial lemniscus and the ventroposterior lateral/medial nuclei of the thalamus and/or the posterior thalamic nucleus resulted in bilateral mechanical pain hypersensitivity. All of the animals displaying CPSP also had impaired motor coordination, while control rats with intra-thalamic saline developed no central pain or motor deficits. GBP had a dose-related anti-allodynic effect after a single administration (1, 10, or 100 mg/kg) on day 7 post-ITC, with significant effects lasting at least 5 h for the higher doses. However, repeated treatment, once a day for two weeks, resulted in complete loss of effectiveness (drug tolerance) at 10 mg/kg, while effectiveness remained at 100 mg/kg, although the time period of efficacious analgesia was reduced. In addition, GBP did not change the basal pain sensitivity and the motor impairment caused by the ITC lesion, suggesting selective action of GBP on the somatosensory system.
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Activated cytotoxic lymphocytes promote tumor progression by increasing the ability of 3LL tumor cells to mediate MDSC chemoattraction via Fas signaling.
Cell. Mol. Immunol.
PUBLISHED: 02-20-2014
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The Fas/FasL system transmits intracellular apoptotic signaling, inducing cell apoptosis. However, Fas signaling also exerts non-apoptotic functions in addition to inducing tumor cell apoptosis. For example, Fas signaling induces lung cancer tumor cells to produce prostaglandin E2 (PGE2) and recruit myeloid-derived suppressor cells (MDSCs). Activated cytotoxic T lymphocytes (CTLs) induce and express high levels of FasL, but the effects of Fas activation initiated by FasL in CTLs on apoptosis-resistant tumor cells remain largely unclear. We purified activated CD8(+) T cells from OT-1 mice, evaluated the regulatory effects of Fas activation on tumor cell escape and investigated the relevant mechanisms. We found that CTLs induced tumor cells to secrete PGE2 and increase tumor cell-mediated chemoattraction of MDSCs via Fas signaling, which was favorable to tumor growth. Our results indicate that CTLs may participate in the tumor immune evasion process. To the best of our knowledge, this is a novel mechanism by which CTLs play a role in tumor escape. Our findings implicate a strategy to enhance the antitumor immune response via reduction of negative immune responses to tumors promoted by CTLs through Fas signaling.Cellular & Molecular Immunology advance online publication, 28 April 2014; doi:10.1038/cmi.2014.21.
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Prospective induction of peripheral neuropathy by the use of Tartarian Buckwheat.
J. Neurol. Sci.
PUBLISHED: 02-10-2014
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Tartarian Buckwheat is an effective hypoglycemic medicinal herb. Its main active ingredients are flavonoids. We report here 5 cases of new onset polyneuropathy with dyskinesia prospectively induced by tartarian buckwheat products. Clinical and electrophysiological evidence along with laboratory tests were reviewed and analyzed. All patients were male, with an average age of 52.2±10.9years old (range: 40-66years) and had a recent history of using tartarian buckwheat for diabetes therapy. The average time of use was 2.5±1.0months (range: 1.5-4months). The average duration of the clinical course was 0.9±0.2months (range: 0.5-1months). Symptoms included numbness and weakness of the limbs (5/5, 100%), hoarseness (4/5, 80%), dysphagia (1/5, 20%), bilateral facial paralysis (1/5, 20%), urinary disorders (3/5, 60%) and gonadal abnormality (4/4, 100%). Nerve conduction studies suggested more severe damages in motor nerves than sensory nerves. All the patients showed abnormality on Von Frey filaments determination. Hence, tartarian buckwheat products may cause toxic peripheral nerve lesion and the use of herbal medication needs to be better regulated and closely monitored.
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Safety assessment of the fermented Phylloporia ribis (Lonicera japonica Thunb.) mycelia by oral acute toxicity study in mice and 90-day feeding study in rats.
Food Chem. Toxicol.
PUBLISHED: 02-07-2014
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Phylloporia ribis is an edible fungus in China. Its fermented mycelia have been approved by the National Health and Family Planning Commission (NHFPC) of PR China for use as a novel food material, but little information on its safety is available. The present research was the first to evaluate acute and subchronic toxicity in experimental animals of fermented Phylloporia ribis mycelia (FPM) following standard procedures. In acute toxicity study, FPM was orally administered to male and female mice twice a day at single dose of 10 g/kg bw. The Maximum Tolerated Dose (MTD) of FPM for mice of both sexes was over 10 g/kg bw. No death and abnormal behaviors occurred during 14 days study except for an increased locomotor activity in three animals. In 90-day feeding study, male and female Sprague-Dawley rats were fed diets containing 10.0%, 5.0%, 2.5%, 1.25% and 0% (control) FPM for 90 days. The treatment caused no effects on mortality, gross pathology, histology, hematology, and blood chemistry, no dose-dependent changes in food consumption, but caused effect on body weight gain compared with control group. The No Observed Adverse-Effect Level (NOAEL) of FPM was greater than 8.7 g/kg bw/day in both sexes of rats.
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Multitargeted antiangiogenic tyrosine kinase inhibitors combined to chemotherapy in metastatic breast cancer: a systematic review and meta-analysis.
Eur. J. Clin. Pharmacol.
PUBLISHED: 01-28-2014
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We undertook a meta-analysis of randomized trials to evaluate the efficacy of multitargeted antiangiogenic tyrosine kinase inhibitors (MATKIs) in addition to chemotherapy in metastatic breast cancer.
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Polyamidoamine dendrimers as off-column binding agent and in-column pseudostationary phase for efficient and sensitive capillary electrophoretic analysis of fluoroquinolones in chicken muscles.
Food Chem
PUBLISHED: 01-26-2014
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A capillary electrophoresis method based on polyamidoamine dendrimers has been developed for quick and sensitive detection of moxifloxacin, gatifloxacin, lomefloxacin, enoxacin, ofloxacin and pazufloxacin. Increasing buffer alkalinity led to enhanced sensitivity, whereas the polyamidoamine-fluoroquinolone interactions, i.e., in-cavity hydrogen bonding/hydrophobic interaction and electrostatic interaction, contributed to the improvement in both separation efficiency and detection sensitivity. By using 1 mM polyamidoamine generation 0.5 as binding agent in sample solution and 0.1 ?M polyamidoamine generation zero as pseudostationary phase to the running buffer of 5 mM sodium tetraborate at pH 9.3, the six fluoroquinolones were baseline separated in <10 min with detection limits at ng/mL level. Coupled with liquid-liquid extraction, the proposed method was successfully applied in the determination of fluoroquinolones in chicken muscle samples.
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Lentiviral-mediated expression of SATB2 promotes osteogenic differentiation of bone marrow stromal cells in vitro and in vivo.
Eur. J. Oral Sci.
PUBLISHED: 01-23-2014
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Special AT-rich sequence-binding protein 2 (SATB2 ) acts as a potent transcription factor to promote osteoblast differentiation and bone regeneration. In this study, we first used lentiviral-mediated gene transfer of Satb2 into mouse bone marrow stromal cells (BMSCs) and investigated the capacity of SATB2 overexpression to promote osteogenic differentiation in vitro and in vivo. We found that LV-Satb2 -transduced BMSCs produced SATB2 protein and underwent rapid and marked osteogenic differentiation, as demonstrated by increased expression of osteoblastic genes, including runt-related transcription factor 2 (Runx2), transcription factor Sp7 (Sp7), activating transcription factor 4 (Atf4), and bone sialoprotein (Bsp), and increased alkaline phosphatase activity and Alizarin Red S staining. To analyze the induction of bone formation in vivo, LV-Satb2-transduced BMSCs were implanted into the hindlimbs of syngeneic mice, with ?-tricalcium phosphate as the scaffolding material. Four weeks after implantation, transduction with LV-Satb2 had greatly enhanced the formation of new bone. These data demonstrated the capacity of lentiviral-mediated SATB2 to promote the osteogenic differentiation of BMSCs in vitro and to enhance bone formation through a tissue-engineering technique that may be useful in bone-regenerative medicine.
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Stimulus-responsive polymeric micelles for the light-triggered release of drugs.
Carbohydr Polym
PUBLISHED: 01-06-2014
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Ethyl cellulose macroinitiator was firstly synthesized by direct acylation of ethyl cellulose with 2-bromopropionyl bromide in a room temperature. And a light-responsive triblock copolymer of ethyl cellulose-g-poly(2-hydroxyethyl methacrylate)-g-poly(spiropyran ether methacrylate) (EC-g-PHEMA-g-PSPMA) was prepared by atom transfer radial polymerization. The amphiphilic structure of the copolymer enabled it to aggregate into spherical micelles in aqueous solution with an average diameter of 100 nm. The micelles exhibited light-responsive performance because of the SPMA monomer. The hydrophobic side chain of PSPMA became hydrophilic under UV light, which decreased the average size of the micelles. Additionally, the diameters of the micelles can be recovered when subsequently irradiated with visible light. The loading and light-triggered release profiles of model drugs were also investigated, and results showed that the release behavior can be controlled by changing the light wavelength.
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A Challenge for the Seed Mixture Refuge Strategy in Bt Maize: Impact of Cross-Pollination on an Ear-Feeding Pest, Corn Earworm.
PLoS ONE
PUBLISHED: 01-01-2014
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To counter the threat of insect resistance, Bacillus thuringiensis (Bt) maize growers in the U.S. are required to plant structured non-Bt maize refuges. Concerns with refuge compliance led to the introduction of seed mixtures, also called RIB (refuge-in-the-bag), as an alternative approach for implementing refuge for Bt maize products in the U.S. Maize Belt. A major concern in RIB is cross-pollination of maize hybrids that can cause Bt proteins to be present in refuge maize kernels and negatively affect refuge insects. Here we show that a mixed planting of 5% nonBt and 95% Bt maize containing the SmartStax traits expressing Cry1A.105, Cry2Ab2 and Cry1F did not provide an effective refuge for an important above-ground ear-feeding pest, the corn earworm, Helicoverpa zea (Boddie). Cross-pollination in RIB caused a majority (>90%) of refuge kernels to express ? one Bt protein. The contamination of Bt proteins in the refuge ears reduced neonate-to-adult survivorship of H. zea to only 4.6%, a reduction of 88.1% relative to larvae feeding on ears of pure non-Bt maize plantings. In addition, the limited survivors on refuge ears had lower pupal mass and took longer to develop to adults.
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Cry1F Resistance in Fall Armyworm Spodoptera frugiperda: Single Gene versus Pyramided Bt Maize.
PLoS ONE
PUBLISHED: 01-01-2014
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Evolution of insect resistance to transgenic crops containing Bacillus thuringiensis (Bt) genes is a serious threat to the sustainability of this technology. However, field resistance related to the reduced efficacy of Bt maize has not been documented in any lepidopteran pest in the mainland U.S. after 18 years of intensive Bt maize planting. Here we report compelling evidence of field resistance in the fall armyworm, Spodoptera frugiperda (J.E. Smith), to Cry1F maize (TC 3507) in the southeastern region of the U.S. An F2 screen showed a surprisingly high (0.293) Cry1F resistance allele frequency in a population collected in 2011 from non-Bt maize in south Florida. Field populations from non-Bt maize in 2012-2013 exhibited 18.8-fold to >85.4-fold resistance to purified Cry1F protein and those collected from unexpectedly damaged Bt maize plants at several locations in Florida and North Carolina had >85.4-fold resistance. In addition, reduced efficacy and control failure of Cry1F maize against natural populations of S. frugiperda were documented in field trials using Cry1F-based and pyramided Bt maize products in south Florida. The Cry1F-resistant S. frugiperda also showed a low level of cross-resistance to Cry1A.105 and related maize products, but not to Cry2Ab2 or Vip3A. The occurrence of Cry1F resistance in the U.S. mainland populations of S. frugiperda likely represents migration of insects from Puerto Rico, indicating the great challenges faced in achieving effective resistance management for long-distance migratory pests like S. frugiperda.
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Primary squamous cell carcinoma of the breast with unusual basal-HER2 phenotype.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To report three cases of primary squamous cell carcinoma of the breast with an unusual "basal-HER2" phenotype.
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Sumoylation modulates oxidative stress relevant to the viability and functionality of pancreatic beta cells.
Am J Transl Res
PUBLISHED: 01-01-2014
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Sumoylation is an evolutionarily conserved regulatory mechanism to play an important role in various cellular processes through modulation of protein localization, stability and functionality. Recent studies including ours have consistently demonstrated that sumoylation provides protection for cells against oxidative stress. Given that pancreatic beta cells are a vulnerable target of oxidative stress, we thus in this minireview, updated the advancement of sumoylation in the regulation of ROS generation, and discussed its impact on several critical signaling pathways relevant to beta cells against oxidative stress and maintenance of functionality. Specifically, we bring together how sumoylation represses intracellular ROS formation, and protects beta cells against oxidative stress through regulating I?B/NF?B, JNK/c-Jun, and Maf/Nrf2 pathways. The tight implication of sumoylation in oxidative stress reflects that it could be an essential mechanism for beta cells to adapt to the detrimental cellular microenvironment.
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Identification of a DNA methylome profile of esophageal squamous cell carcinoma and potential plasma epigenetic biomarkers for early diagnosis.
PLoS ONE
PUBLISHED: 01-01-2014
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DNA methylation is a critical epigenetic mechanism involved in key cellular processes. Its deregulation has been linked to many human cancers including esophageal squamous cell carcinoma (ESCC). This study was designed to explore the whole methylation status of ESCC and to identify potential plasma biomarkers for early diagnosis. We used Infinium Methylation 450k array to analyze ESCC tissues (n = 4), paired normal surrounding tissues (n = 4) and normal mucosa from healthy individuals (n = 4), and combined these with gene expression data from the GEO database. One hundred and sixty eight genes had differentially methylated CpG sites in their promoter region and a gene expression pattern inverse to the direction of change in DNA methylation. These genes were involved in several cancer-related pathways. Three genes were validated in additional 42 ESCC tissues and paired normal surrounding tissues. The methylation frequency of EPB41L3, GPX3, and COL14A1 were higher in tumor tissues than in normal surrounding tissues (P < 0.017). The higher methylation frequency of EPB41l3 was correlated with large tumor size (P = 0.044) and advanced pT tumor stage (P = 0.001). The higher methylation frequency of GPX3 and COL14A1 were correlated with advanced pN tumor stage (P = 0.001 and P < 0.001). The methylation of EPB41L3, GPX3, and COL14A1 genes were only found in ESCC patients' plasma, but not in normal individuals upon testing 42 ESCC patients and 50 healthy individuals. Diagnostic sensitivity was increased when methylation of any of the 3 genes were counted (64.3% sensitivity and 100% specificity). These differentially methylated genes in plasma may be used as biomarkers for early diagnosis of ESCC.
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Use of polypropylene mesh in the management of a contaminated large ventral hernia: a contraindication or a solution?
Am Surg
PUBLISHED: 12-20-2013
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Management of contaminated large ventral hernias is still a challenge as a result of massive loss of muscular and fascial tissues in the abdominal wall, traditional contraindication to use of a prosthesis, and complicated perioperative management. This study aimed to provide a solution for this challenging dilemma using monofilament polypropylene mesh (Marlex; Bard) in the Sublay-Bridge fashion. Twenty-three consecutive patients with contaminated large ventral hernias from 2009 to 2011 were identified. Preoperatively, source of contamination at the surgical site was managed through oral antibiotics, wound débridement, and dressing change; the hernia content was reduced into the abdominal cavity gradually and an abdominal binder was applied. Marlex meshes in the Sublay-Bridge fashion were used in these patients. Demographic and perioperative data were collected. Fourteen males and nine females were included with a mean age of 52.5 ± 10.5 years and a mean body mass index of 25.2 ± 6.1 kg/m(2). Twelve patients underwent ostomy takedown, which was the most common indication. Mean hernia size was 120.5 ± 18.5 cm(2) and a mean mesh size was 380.0 ± 80.5 cm(2). The mean operative time was 125.5 ± 35.5 minutes and the hospital stay was 10.0 ± 3.5 days. Twenty-three patients had a mean follow-up period of 12.5 ± 6.5 months. An iatrogenic bladder injury occurred because of severe prevesical adhesion attributed to previous prosthesis repair. There was no presentation of abdominal compartment syndrome. Four patients developed surgical site infection and managed with conservative therapy without mesh removal. Three patients had seromas and underwent aspiration guided by B-ultrasound. Three patients reported chronic foreign body sensation. No recurrence was followed up. Repair of contaminated large ventral hernia using a Marlex mesh in the Sublay-Bridge fashion is safe and efficient management. Perioperative management and operative technology play important roles in dealing with this problem.
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Two Novel Anti-Inflammatory 21-Nordammarane Saponins from Tetraploid Jiaogulan ( Gynostemma pentaphyllum ).
J. Agric. Food Chem.
PUBLISHED: 12-17-2013
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Two novel 20-oxo-21-nordammar-22, 24-diene saponins, 21-norgypenosides A (1) and B (2), were characterized from the aerial parts of tetraploid Jiaogulan ( Gynostemma pentaphyllum ), a popular tea ingredient. Their structures, including the absolute configurations, were comprehensively elucidated by HRESIMS, 1D and 2D NMR data, chemical degradation, and through comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. The two compounds suppressed the expression of interleukin (IL)-1?, cyclooxygenase (COX)-2, and tumor necrosis factor (TNF)-? mRNAs in the lipopolysaccharide-induced RAW 264.7 mouse macrophage cells at 10 and 100 ?g/mL, suggesting their potential anti-inflammatory effects.
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Determination of chlorinated phenoxy acid herbicides in tobacco by modified quechERS extraction and high-performance liquid chromatography/tandem mass spectrometry.
J AOAC Int
PUBLISHED: 11-29-2013
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A new method for determination of phenoxy acid herbicide residues in tobacco based on the use of liquid extraction/partition and dispersive SPE followed by HPLC/electrospray ionization-MS/MS is reported. Formic acid (2%, v/v) in acetonitrile as the extraction solvent and inclusion of citrate buffer helped partitioning of all analytes into the acetonitrile phase. Quantitative analysis was done in the multiple-reaction monitoring mode using two combinations of selected precursor ion and product ion transition for each compound. The recoveries obtained for each pesticide ranged between 85 and 110% at two spike concentration levels. Good linear relationships were observed, with the correlation coefficient (r2) >0.998 for all analytes. The method is simple, efficient, and sensitive, and each of its performance characteristics meets the requirements for determination of phenoxy acid herbicide residues in tobacco.
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TNFRSF10A-LOC389641 rs13278062 But Not REST-C4orf14-POLR2B-IGFBP7 rs1713985 Was Found Associated With Age-Related Macular Degeneration in a Chinese Population.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 11-16-2013
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To reassess the association between TNFRSF10-LOC389641 rs13278062 and REST-C4orf14-POLR2B-IGFBP7 rs1713985 with the risk of AMD in a Chinese case-control collection.
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Lysing activity of an indigenous algicidal bacterium Aeromonas sp. against Microcystis spp. isolated from Lake Taihu.
Environ Technol
PUBLISHED: 11-07-2013
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This study aimed to isolate and characterize an indigenous algicidal bacterium named LTH-1 and its algae-lysing compounds active against three Microcystis aeruginosa strains (toxic TH1, nontoxic TH2 and standard FACHB 905). The LTH-1 isolated from Lake Taihu, near Wuxi City in China, was identified as Aeromonas sp. based on its morphological characteristic features and phylogenetic analysis by sequencing of 16S rDNA. Extracellular compounds produced by LTH-1 showed strong algaelysing activity, and they were water-soluble and heat-tolerant, with a molecular mass lower than 2 kDa. Two algae-lysing compounds were isolated and purified from extracellular filtrate using silica gel column chromatography. One of these was identified as phenylalanine (C9H11NO2, m/z 166.0862) and the other (C8H16N2O3, m/z 189.1232) was unidentified by hybrid ion trap/time-of-flight mass spectrometry coupled with a high-performance liquid chromatography (LC/MS-IT-TOF) system. The half maximal effective concentration (EC50) of phenylalanine produced by LTH-1 against FACHB 905 was 68.2 +/- 8.2 microg mL(-1) in 48h. These results suggest that the algicidal Aeromonas sp. LTH-1 could play a role in controlling Microcystis blooms, and its extracellular compounds are also potentially useful for regulating blooms of the harmful M. aeruginosa.
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Assessing the optimal dose for Cetrorelix in Chinese women undergoing ovarian stimulation during the course of IVF-ET treatment.
Am J Transl Res
PUBLISHED: 10-29-2013
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We conducted a prospective, randomized, and controlled trial to assess the optimal dose for GnRH antagonist, cetrorelix, for Chinese women during the course of ovarian stimulation. The patients were randomly divided into two groups, in which 48 patients were advised to inject 0.25 mg Cetrorelix daily (the 0.25 mg group), while 39 patients were instructed to receive a daily dose of 0.125 mg cetrorelix (the 0.125 mg group). In general, a daily dose of 0.125 mg cetrorelix could be more optimal for Chinese women as manifested by the lower cancellation rate, higher implantation rate and clinical pregnancy rate. Specifically, daily administration of 0.125 mg cetrorelix for patients under 35 years old is associated with a 3-fold higher implantation rate and a 5-fold higher clinical pregnancy rate as compared with that of those patients ? 35 years old. On the contrary, higher rates for implantation and clinical pregnancy were noted by daily injection of 0.25 mg cetrorelix in elder patients (? 35 years old) as compared with that of young patients (< 35 years old). Together, our data suggest that a daily dose of 0.125 mg cetrorelix could be more optimal for patients < 35 years old, while 0.25 mg/day of cetrorelix are likely conducive to higher implantation and clinical pregnancy rate for those patients ? 35 years old. These data could be important for preventing LH surge while maintaining optimal LH levels necessary for embryo implantation for Chinese women during the course of IVF-ET treatment.
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[Effect of salt stress on DNA methylation in Isatis indigotica].
Zhong Yao Cai
PUBLISHED: 10-19-2013
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To investigate the effect of salt stress on DNA methylation in Isatis indigotica.
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Expression, purification, and solid-state NMR characterization of the membrane binding heme protein nitrophorin 7 in two electronic spin States.
Biochemistry
PUBLISHED: 09-26-2013
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The nitrophorins (NPs) comprise a group of NO transporting ferriheme b proteins found in the saliva of the blood sucking insect Rhodnius prolixus . In contrast to other nitrophorins (NP1-4), the recently identified membrane binding isoform NP7 tends to form oligomers and precipitates at higher concentrations in solution. Hence, solid-state NMR (ssNMR) was employed as an alternative method to gain structural insights on the precipitated protein. We report the expression and purification of (13)C,(15)N isotopically labeled protein together with the first ssNMR characterization of NP7. Because the size of NP7 (21 kDa) still provides a challenge for ssNMR, the samples were reverse labeled with Lys and Val to reduce the number of crosspeaks in two-dimensional spectra. The two electronic spin states with S = 1/2 and S = 0 at the ferriheme iron were generated by the complexation with imidazole and NO, respectively. ssNMR spectra of both forms are well resolved, which allows for sequential resonance assignments of 22 residues. Importantly, the ssNMR spectra demonstrate that aggregation does not affect the protein fold. Comparison of the spectra of the two electronic spin states allows the determination of paramagnetically shifted cross peaks due to pseudocontact shifts, which assists the assignment of residues close to the heme center.
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[Analysis of sensitive spectral bands for burning status detection using hyper-spectral images of Tiangong-01].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 09-25-2013
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To obtain the sensitive spectral bands for detection of information on 4 kinds of burning status, i. e. flaming, smoldering, smoke, and fire scar, with satellite data, analysis was conducted to identify suitable satellite spectral bands for detection of information on these 4 kinds of burning status by using hyper-spectrum images of Tiangong-01 (TG-01) and employing a method combining statistics and spectral analysis. The results show that: in the hyper-spectral images of TG-01, the spectral bands differ obviously for detection of these 4 kinds of burning status; in all hyper-spectral short-wave infrared channels, the reflectance of flaming is higher than that of all other 3 kinds of burning status, and the reflectance of smoke is the lowest; the reflectance of smoke is higher than that of all other 3 kinds of burning status in the channels corresponding to hyper-spectral visible near-infrared and panchromatic sensors. For spectral band selection, more suitable spectral bands for flaming detection are 1 000.0-1 956.0 and 2 020.0-2 400.0 nm; the suitable spectral bands for identifying smoldering are 930.0-1 000.0 and 1 084.0-2 400.0 nm; the suitable spectral bands for smoke detection is in 400.0-920.0 nm; for fire scar detection, it is suitable to select bands with central wavelengths of 900.0-930.0 and 1 300.0-2 400.0 nm, and then to combine them to construct a detection model.
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Effects of semaphorin 3A on retinal pigment epithelial cell activity.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 09-19-2013
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Semaphorin 3A (Sema3A), a chemorepellant guidance protein, has been shown to be crucial for neural and vascular remodeling. This study is designed to examine the effects of Sema3A on RPE cell activity both in vitro and in vivo.
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Animal toxicity of hairpin pyrrole-imidazole polyamides varies with the turn unit.
J. Med. Chem.
PUBLISHED: 09-09-2013
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A hairpin pyrrole-imidazole polyamide (1) targeted to the androgen receptor consensus half-site was found to exert antitumor effects against prostate cancer xenografts. A previous animal study showed that 1, which has a chiral amine at the ?-position of the ?-aminobutyric acid turn (?-turn), did not exhibit toxicity at doses less than 10 mg/kg. In the same study, a polyamide with an acetamide at the ?-position of the ?-turn resulted in animal morbidity at 2.3 mg/kg. To identify structural motifs that cause animal toxicity, we synthesized polyamides 1-4 with variations at the ?- and ?-positions in the ?-turn. Weight loss, histopathology, and serum chemistry were analyzed in mice post-treatment. While serum concentration was similar for all four polyamides after injection, dose-limiting liver toxicity was only observed for three polyamides. Polyamide 3, with an ?-acetamide, caused no significant evidence of rodent toxicity and retains activity against LNCaP xenografts.
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[Cadmium and selected heavy metals in soils of Jianping area in Wushan County, the Three Gorges region: distribution and source recognition].
Huan Jing Ke Xue
PUBLISHED: 08-17-2013
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Abnormally high cadmium (Cd) concentrations were existed in soils of Jianping area in the Three Gorges region, but little information is available about the geochemical distribution of Cd and source identification. In the present paper, total contents of Cd and other selected heavy metal elements, the characteristics of soil, the contents of Cd in typical soil profiles, and chemical forms of Cd in selected soils were studied. The correlation analysis, the principal component analysis, and the comparison between different soil types were conducted. The concentration distribution of Cd and selected elements in local soils was investigated and their sources were identified. The results showed that Cd in local rocks, coal and coal wastes ranged from 0.22-101 mg x kg(-1), 0.42-42 mg x kg(-1) in the arable topsoil, and 0. 12-8.5 mg x kg(-1) in natural soils. The soils were also rich in other elements such as V, Cr, Ni and Zn. The weak acid fraction of Cd accounted for 17%-35% of total contents. This study demonstrated that soils from the Jianping area of Wushan County had a serious Cd pollution, and both local rocks and soils display a significant geochemical interrelation. Cd particularly accumulates in the topsoil, and it is mainly derived from the geogenic source. Human such as the historical coal mining may overload Cd in the soils. The local soils had a high portion of bioavailable Cd, through which Cd may easily transfer to and accumulate in the local crops growing in the Cd-rich soils and cause potential health risk to local residents.
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MrgC agonism at central terminals of primary sensory neurons inhibits neuropathic pain.
Pain
PUBLISHED: 08-14-2013
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Chronic neuropathic pain is often refractory to current pharmacotherapies. The rodent Mas-related G-protein-coupled receptor subtype C (MrgC) shares substantial homogeneity with its human homologue, MrgX1, and is located specifically in small-diameter dorsal root ganglion neurons. However, evidence regarding the role of MrgC in chronic pain conditions has been disparate and inconsistent. Accordingly, the therapeutic value of MrgX1 as a target for pain treatment in humans remains uncertain. Here, we found that intrathecal injection of BAM8-22 (a 15-amino acid peptide MrgC agonist) and JHU58 (a novel dipeptide MrgC agonist) inhibited both mechanical and heat hypersensitivity in rats after an L5 spinal nerve ligation (SNL). Intrathecal JHU58-induced pain inhibition was dose dependent in SNL rats. Importantly, drug efficacy was lost in Mrg-cluster gene knockout (Mrg KO) mice and was blocked by gene silencing with intrathecal MrgC siRNA and by a selective MrgC receptor antagonist in SNL rats, suggesting that the drug action is MrgC dependent. Further, in a mouse model of trigeminal neuropathic pain, microinjection of JHU58 into ipsilateral subnucleus caudalis inhibited mechanical hypersensitivity in wild-type but not Mrg KO mice. Finally, JHU58 attenuated the miniature excitatory postsynaptic currents frequency both in medullary dorsal horn neurons of mice after trigeminal nerve injury and in lumbar spinal dorsal horn of mice after SNL. We provide multiple lines of evidence that MrgC agonism at spinal but not peripheral sites may constitute a novel pain inhibitory mechanism that involves inhibition of peripheral excitatory inputs onto postsynaptic dorsal horn neurons in different rodent models of neuropathic pain.
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Microbial community characterization, activity analysis and purifying efficiency in a biofilter process.
J Environ Sci (China)
PUBLISHED: 08-09-2013
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The growth and metabolism of microbial communities on biologically activated carbon (BAC) play a crucial role in the purification of drinking water. To gain insight into the growth and metabolic characteristics of microbial communities and the efficiency of drinking water treatment in a BAC filter, we analyzed the heterotrophic plate count (HPC), phospholipid, dehydrogenase, metabolic function and water quality parameters during start-up and steady-state periods. In the start-up process of the filter with natural biofilm colonization, the variation in heterotrophic plate count levels was S-curved. The total phospholipid level was very low during the first 5 days and reached a maximum value after 40 days in the filter. The activity of dehydrogenase gradually increased during the first 30 days and then reached a plateau. The functional diversity of the microbial community in the filter increased, and then reached a relatively stable level by day 40. After an initial decrease, which was followed by an increase, the removal rate of NH4(+)-N and COD(Mn) became stable and was 80% and 28%, respectively, by day 40. The consumption rate of dissolved oxygen reached a steady level after 29 days, and remained at 18%. At the steady operation state, the levels of HPC, phospholipid, dehydrogenase activity and carbon source utilization had no significant differences after 6 months compared to levels measured on day 40. The filter was shown to be effective in removing NH4(+)-N, NO2(-)-N, COD(Mn), UV254, biodegradable dissolved organic carbon and trace organic pollutants from the influent. Our results suggest that understanding changes in the growth and metabolism of microorganisms in BAC filter could help to improve the efficiency of biological treatment of drinking water.
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Familial Coaggregation of Alzheimers Disease and Parkinsons Disease: Systematic Review and Meta-Analysis.
Neuroepidemiology
PUBLISHED: 08-05-2013
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Background: Familial aggregation has been shown for Alzheimers disease (AD) and Parkinsons disease (PD) separately, and it has been hypothesized that these diseases also coaggregate in families. Methods: The authors investigated familial coaggregation of AD and PD by conducting a systematic review and meta-analysis. PubMed was searched for relevant studies published through the end of October 2012. Three independent investigators screened publications and extracted data. Relative risk estimates of AD risk associated with family history of PD or parkinsonism, or PD risk associated with family history of AD or dementia, were summarized into metaestimates using random effects models. Heterogeneity and publication bias were tested using Higgins and Eggers tests, respectively. Results: We included 16 studies in the review, with 14 included in any meta-analysis. AD risk associated with family history of PD yielded a summary hazard ratio of 1.18 (95% CI: 1.00-1.39) based on 5 reconstructed cohort studies and a summary odds ratio (OR) of 1.40 (95% CI: 0.92-2.12) based on 7 case-control studies. PD risk associated with family history of AD yielded a summary OR of 0.75 (95% CI: 0.49-1.16) based on 3 studies. There was no significant heterogeneity among studies, nor significant publication bias. Conclusions: There may be familial coaggregation of AD and PD, although the association was modest and only apparent when studying AD risk associated with family history of PD. © 2013 S. Karger AG, Basel.
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[Land cover and landscape pattern changes in Poyang Lake region of China in 1980-2010].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 08-01-2013
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Based on the land cover datasets of Poyang Lake region in 1980, 2005, and 2010, and by using GIS, RS, and landscape ecology approaches, this paper studied the land cover and landscape pattern changes in this region from 1980 to 2010, and quantitatively analyzed the land cover types change degree, patch area index, patch shape index, margin density index, and landscape diversity index. In 1980-2010, the main land cover types in this region were paddy field, inland water, evergreen broadleaf forest, and urban built-up area, and their areas and spatial patterns varied dramatically. Overall, the areas of inland water and urban built-up area had a significant increase, while those of paddy field and dry farmland decreased somewhat. Due to the effects of population growth and economic development, the landscape fragmentation degree and landscape diversity index presented a decreasing trend, but the decrement was small, which implied that the previous environmental management of this region had exerted important roles, but a long term challenge was still faced with between the regional environmental protection and sustainable development.
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Analysis of 118 Pesticides in Tobacco after Extraction With the Modified QuEChRS Method by LC-MS-MS.
J Chromatogr Sci
PUBLISHED: 07-25-2013
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A liquid chromatography-tandem quadrupole mass spectrometry (LC-MS-MS) multi-residue method for the simultaneous target analysis of a wide range of pesticides in tobacco has been developed. Gradient elution has been used in conjunction with positive mode electrospray ionization tandem mass spectrometry to detect up to 118 pesticides in tobacco. The recoveries obtained for each pesticide ranged between 70 and 118% at two spiked concentration levels. Good linear relationships were observed with correlation coefficients r(2) > 0.992 for all analytes. The established method was successfully applied to the determination of pesticide residues in real tobacco samples in order to validate the suitability for routine analysis.
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Conventional and kilohertz-frequency spinal cord stimulation produces intensity- and frequency-dependent inhibition of mechanical hypersensitivity in a rat model of neuropathic pain.
Anesthesiology
PUBLISHED: 07-25-2013
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Spinal cord stimulation (SCS) is a useful neuromodulatory technique for treatment of certain neuropathic pain conditions. However, the optimal stimulation parameters remain unclear.
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Crystal Structure of Prp5p Reveals Interdomain Interactions that Impact Spliceosome Assembly.
Cell Rep
PUBLISHED: 07-21-2013
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The DEAD-box adenosine triphosphatase (ATPase) Prp5p facilitates U2 small nuclear ribonucleoprotein particle (snRNP) binding to the intron branch site region during spliceosome assembly. We present crystal structures of S. cerevisiae Prp5p alone and in complex with ADP at 2.12 Å and 1.95 Å resolution. The three-dimensional packing of Prp5p subdomains differs strikingly from that so far observed in other DEAD-box proteins: two RecA-like subdomains adopt an "open state" conformation stabilized by extensive interactions involving sequences that flank the two subdomains. This conformation is distinct from that required for ATP hydrolysis. Consistent with this, Prp5p mutations that destabilize interdomain interactions exhibited increased ATPase activity in vitro and inhibited splicing of suboptimal branch site substrates in vivo, whereas restoration of interdomain interactions reversed these effects. We conclude that the Prp5p open state conformation is biologically relevant and that disruption of the interdomain interaction facilitates a large-scale conformational change of Prp5p during U2 snRNP-branch site recognition.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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