JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Simultaneous sequencing of oxidized methylcytosines produced by TET/JBP dioxygenases in Coprinopsis cinerea.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
TET/JBP enzymes oxidize 5-methylpyrimidines in DNA. In mammals, the oxidized methylcytosines (oxi-mCs) function as epigenetic marks and likely intermediates in DNA demethylation. Here we present a method based on diglucosylation of 5-hydroxymethylcytosine (5hmC) to simultaneously map 5hmC, 5-formylcytosine, and 5-carboxylcytosine at near-base-pair resolution. We have used the method to map the distribution of oxi-mC across the genome of Coprinopsis cinerea, a basidiomycete that encodes 47 TET/JBP paralogs in a previously unidentified class of DNA transposons. Like 5-methylcytosine residues from which they are derived, oxi-mC modifications are enriched at centromeres, TET/JBP transposons, and multicopy paralogous genes that are not expressed, but rarely mark genes whose expression changes between two developmental stages. Our study provides evidence for the emergence of an epigenetic regulatory system through recruitment of selfish elements in a eukaryotic lineage, and describes a method to map all three different species of oxi-mCs simultaneously.
Related JoVE Video
Differential proteomic analyses of cataracts from rat models of type 1 and 2 diabetes.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 11-20-2014
Show Abstract
Hide Abstract
PURPOSE. To identify differential changes in proteins and metabolites underlying "fast" type 1 (T1DC) and "slow" type 2 (T2DC) diabetic cataract (DC) formation in rat. METHODS. Rat models of type 1 and 2 diabetes consisted of streptozotocin injection without and with high fat diet, respectively. Cataract progression was examined weekly. At week 6 total protein changes were comparatively and quantitatively assessed by two-dimensional differential in-gel electrophoresis coupled with by mass spectrometry, and relevant metabolic changes were examined. Differences in high molecular weight (HMW) crystallin species between diabetic and control lenses were similarly identified. RESULTS. Cataracts were morphologically different, progressed more slowly in T2DC vs. T1DC. ?A-crystallin, ?B2-crystallin and ?A4-crystallin were significantly decreased in both DC types vs. control. ?B-crystallin was increased while ?B1-crystallin was markedly decreased in T2DC. In T1DC ?B-crystallin and ?S-crystallin fragmentation were increased. High fat diet by itself had little impact, except for lowering ?S-crystallin fragmentation. Despite significantly decreased opacity, a greater decrease in intermediate filaments (IFs) and more HMW crystallin species were observed in T2DC vs. T1DC. However, aldose reductase expression and activity and sorbitol levels were increased to a greater extent in T1DC, while GSH and NADPH levels were decreased to a greater extent, and ATP level was much lower in T1DC vs. T2DC. CONCLUSIONS. The results suggest that osmotic damage, GSH loss and decreased ATP production might be important pathological mechanisms in T1DC formation, whereas crystallin modification and cross-linking/aggregation as well as IF degradation may play more crucial roles in T2DC formation.
Related JoVE Video
Nonideal ultrathin mantle cloak for electrically large conducting cylinders.
J Opt Soc Am A Opt Image Sci Vis
PUBLISHED: 11-18-2014
Show Abstract
Hide Abstract
Based on the concept of the scattering cancellation technique, we propose a nonideal ultrathin mantle cloak that can efficiently suppress the total scattering cross sections of an electrically large conducting cylinder (over one free-space wavelength). The cloaking mechanism is investigated in depth based on the Mie scattering theory and is simultaneously interpreted from the perspective of far-field bistatic scattering and near-field distributions. We remark that, unlike the perfect transformation-optics-based cloak, this nonideal cloaking technique is mainly designed to minimize simultaneously several scattering multipoles of a relatively large geometry around considerably broad bandwidth. Numerical simulations and experimental results show that the antiscattering ability of the metasurface gives rise to excellent total scattering reduction of the electrically large cylinder and remarkable electric-field restoration around the cloak. The outstanding cloaking performance together with the good features of and ultralow profile, flexibility, and easy fabrication predict promising applications in the microwave frequencies.
Related JoVE Video
Effect of ulinastatin on liver function of patients after bilateral total knee arthroplasty.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 11-01-2014
Show Abstract
Hide Abstract
Objective To investigate the effect of ulinastatin,a urinary trypsin inhibitor,on the postoperative liver function in patients who have received bilateral total knee arthroplasty(TKA)under pneumatic tourniquet. Methods Totally 40 patients who were scheduled to receive bilateral TKA under thigh tourniquet were randomly assigned into trial group(U group,receiving intravenous ulinastatin)and control group(C group,receiving natural saline). All patients received the same general anesthesia and postoperative analgesia. The plasma concentrations of alanine transaminase(ALT),total bilirubin(TBil),and direct bilirubin(DBil)were recorded and compared preoperatively and 4,24,48,and 72 hours after the surgery. Results The demographic data were not significantly different between these two groups(P>0.05). The ALT was not significantly changed after the surgery in the C group(P>0.05)but was significantly decreased 48 hours(P=0.002)and 72 hours(P=0.001)after the surgery in the U group. TBil and DBil were significantly increased 48 hours(P=0.012,P=0.000)and 72 hours(P=0.000,P=0.000)after the surgery in C group,while only that at 48 hours(P=0.010,P=0.038)was significantly increased in the U group. ALT 4 hours(P=0.026),48 hours(P=0.013),72 hours(P=0.004)after the surgery were significantly lower in the U group than those in C group. TBil at the 72 hours postoperatively in U group was significantly lower than that in C group(P=0.036). DBil was not significantly different between C group and U group at all time points(all P>0.05). Conclusion The application of ulinastatin in bilateral TKA can protect postoperative liver function.
Related JoVE Video
[Abnormality of anapastic lymphoma kinase gene and its expression in pediatric neuroblastoma].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 10-28-2014
Show Abstract
Hide Abstract
To correlate the abnormal expression of anapastic lymphoma kinase (ALK) protein with the genetic and epigenetic changes of ALK, and to analyze its clinical application in pediatric neuroblastoma.
Related JoVE Video
Prevalence and Risk Factors for Farmer's Lung in Greenhouse Farmers: An Epidemiological Study of 5,880 Farmers from Northeast China.
Cell Biochem. Biophys.
PUBLISHED: 10-27-2014
Show Abstract
Hide Abstract
The objectives of this epidemiological study were to evaluate the prevalence of farmer's lung disease (FLD) and to explore the potential risk factors for FLD among Chinese greenhouse farmers. A total of 835 plastic film greenhouses, including 5,880 active farmers who engaged in crop cultivation or poultry farming, were randomly selected from the rural regions of Northeastern China. These farmers participated in the study by answering a medical questionnaire. 5,420 greenhouse farmers accepted and answered questionnaires in full (response rate, 92.18 %). Prevalence of FLD among these farmers was 5.7 % (308/5,420). Besides, a number of classic risk factors for FLD were identified, such as years of age, shorter time interval for re-entry greenhouse, ventilation frequency of greenhouse more than once per 4 h, the area of greenhouses greater than 30 m(2) but without a ventilation facility, ventilation duration less than 30 min every time, greenhouse with height less than 1.8 m, greenhouse with humidity greater than 65 %, frequent exposure to moldy materials in greenhouse, living inside greenhouse, and et al. FLD is and will continue to be a real health problem for Chinese farmers. If these preventive measures are implemented, the prevalence of FLD in Chinese greenhouse farmers might be greatly reduced.
Related JoVE Video
Switchable and spacing-tunable dual-wavelength thulium-doped silica fiber laser based on a nonlinear amplifier loop mirror.
Appl Opt
PUBLISHED: 10-17-2014
Show Abstract
Hide Abstract
A kind of switchable and spacing-tunable dual-wavelength thulium-doped silica fiber laser based on a nonlinear amplifier loop mirror is presented and experimentally demonstrated. By adjusting the polarization controllers (PCs), stable dual-wavelength operation is obtained at the 2 ?m band. The optical signal-to-noise ratio (OSNR) is better than 56 dB. The wavelength tuning is performed by applying static strain into the fiber Bragg grating. A tuning range from 0 to 5.14 nm is achieved for the dual-wavelength spacing. By adjusting the PCs properly, the fiber laser can also operate in single-wavelength state with the OSNR for each wavelength more than 50 dB.
Related JoVE Video
Elevated levels of protein in urine in adulthood after exposure to the Chinese famine of 1959-61 during gestation and the early postnatal period.
Int J Epidemiol
PUBLISHED: 10-10-2014
Show Abstract
Hide Abstract
Animal models have suggested that undernutrition during gestation and the early postnatal period may adversely affect kidney development and compromise renal function. As a natural experiment, famines provide an opportunity to test such potential effects in humans. We assessed whether exposure to the Chinese famine of 1959-1961 during gestation and early postnatal life was associated with the levels of proteinuria among female adults three decades after exposure to the famine.
Related JoVE Video
Visceral and somatic hypersensitivity, autonomic cardiovascular dysfunction and low-grade inflammation in a subset of irritable bowel syndrome patients.
J Zhejiang Univ Sci B
PUBLISHED: 10-09-2014
Show Abstract
Hide Abstract
The pathophysiology of irritable bowel syndrome (IBS) is complex and not fully understood, so the aim of this study was to evaluate whether visceral and somatic hypersensitivity, autonomic cardiovascular dysfunction, and low-grade inflammation of the gut wall are associated with diarrhea-predominant IBS (D-IBS). Sixty-two patients with D-IBS and 20 control subjects participated in the study. Using the ascending method of limits (AML) protocol, we demonstrated that D-IBS patients had significantly lower sensory thresholds compared with healthy controls (P<0.001). Using diverse methods, especially the ischemic sensitivity test, for the first time in China, we confirmed that D-IBS patients have somatic hypersensitivity. They had a significantly higher systolic blood pressure and heart rate after a cold stimulus, indicative of autonomic cardiovascular dysfunction. Compared with the control group, D-IBS patients had a significantly higher level of calprotectin (P<0.001). We also found significant correlations between visceral and somatic hypersensitivity, visceral hypersensitivity and autonomic cardiovascular dysfunction, and somatic hypersensitivity and autonomic cardiovascular dysfunction. Our findings may provide valuable suggestions for the treatment of D-IBS.
Related JoVE Video
Statistical Learning Methods for Longitudinal High-dimensional Data.
Wiley Interdiscip Rev Comput Stat
PUBLISHED: 10-07-2014
Show Abstract
Hide Abstract
Recent studies have collected high-dimensional data longitudinally. Examples include brain images collected during different scanning sessions and time-course gene expression data. Because of the additional information learned from the temporal changes of the selected features, such longitudinal high-dimensional data, when incorporated with appropriate statistical learning techniques, are able to more accurately predict disease status or responses to a therapeutic treatment. In this article, we review recently proposed statistical learning methods dealing with longitudinal high-dimensional data.
Related JoVE Video
Photocatalytic Oxidation of Aqueous Ammonia Using Atomic Single Layer Graphitic-C3N4.
Environ. Sci. Technol.
PUBLISHED: 10-01-2014
Show Abstract
Hide Abstract
Direct utilization of solar energy for photocatalytic removal of ammonia from water is a topic of strong interest. However, most of the photocatalysts with effective performance are solely metal-based semiconductors. Here, we report for the first time that a new type of atomic single layer graphitic-C3N4 (SL g-C3N4), a metal-free photocatalyst, has an excellent photocatalytic activity for total ammonia nitrogen (TAN) removal from water. The results demonstrated that over 80% of TAN (initial concentration 1.50 mg·L(-1)) could be removed in 6 h under Xe lamp irradiation (195 mW·cm(-2)). Furthermore, the SL g-C3N4 exhibited a higher photocatalytic activity in alkaline solution than that in neutral or acidic solutions. The investigation suggested that both photogenerated holes and hydroxyl radicals were involved the TAN photocatalytic oxidation process and that the major oxidation product was NO3(-)-N. In addition, SL g-C3N4 exhibited good photocatalytic stability in aqueous solution. This work highlights the appealing application of an inexpensive metal-free photocatalyst in aqueous ammonia treatment.
Related JoVE Video
Effects of PDE4 pathway inhibition in rat experimental stroke.
J Pharm Pharm Sci
PUBLISHED: 09-17-2014
Show Abstract
Hide Abstract
The first genomewide association study indicated that variations in the phosphodiesterase 4D (PDE4D) gene confer risk for ischemic stroke. However, inconsistencies among the studies designed to replicate the findings indicated the need for further investigation to elucidate the role of the PDE4 pathway in stroke pathogenesis. Hence, we studied the effect of global inhibition of the PDE4 pathway in two rat experimental stroke models, using the PDE4 inhibitor rolipram. Further, the specific role of the PDE4D isoform in ischemic stroke pathogenesis was studied using PDE4D knockout rats in experimental stroke.
Related JoVE Video
Characterization and plasmid elimination of NDM-1-producing Acinetobacter calcoaceticus from China.
PLoS ONE
PUBLISHED: 09-02-2014
Show Abstract
Hide Abstract
The presence of multidrug-resistant bacterial pathogens in the environment poses a serious threat to public health. The opportunistic Acinetobacter spp. are among the most prevalent causes of nosocomial infections. Here, we performed complete genome sequencing of the Acinetobacter calcoaceticus strain XM1570, which was originally cultivated from the sputum of a patient diagnosed with pneumonia in Xiamen in 2010. We identified carbapenem resistance associated gene bla(NDM-1) located on a 47.3-kb plasmid. Three methods--natural reproduction, sodium dodecyl sulfate treatment and nalidixic acid treatment--were used to eliminate the bla(NDM-1)-encoding plasmid, which achieved elimination rates of 3.32% (10/301), 83.78% (278/332), and 84.17% (298/354), respectively. Plasmid elimination dramatically increased antibiotic sensitivity, reducing the minimum bacteriostatic concentration of meropenem from 256 µg/ml in the clinical strain to 0.125 µg/ml in the plasmid-eliminated strain. Conjugation transfer assays showed that the bla(NDM-1)-containing plasmid could be transferred into Escherichia coli DH5?:pBR322 in vitro as well as in vivo in mice. The bla(NDM-1) genetic environment was in accordance with that of other bla(NDM-1) genes identified from India, Japan, and Hong-Kong. The multilocus sequence type of the isolate was identified as ST-70. Two novel genes encoding intrinsic OXA and ADC were identified and named as OXA-417 and ADC-72. The finding of bla(NDM-1) in species like A. calcoaceticus demonstrates the wide spread of this gene in gram-negative bacteria which is possible by conjugative plasmid transfer. The results of this study may help in the development of a treatment strategy for controlling NDM-1 bacterial infection and transmission.
Related JoVE Video
[Clinical study in fiberoptic bronchoscopy with a laryngeal mask airway].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-27-2014
Show Abstract
Hide Abstract
To evaluate the usefulness and safety of bronchoscopy by the laryngeal mask airway (LMA) compared with by nose and by mouth.
Related JoVE Video
Identification of a potential novel type of influenza virus in Bovine in China.
Virus Genes
PUBLISHED: 08-21-2014
Show Abstract
Hide Abstract
Bovine influenza virus was first identified in the USA in 2013, and the virus represents a potential novel type of influenza viruses. However, the distribution and evolution of the virus remain unknown. We conducted a pilot survey of bovine influenza virus in China, and identified three bovine influenza viruses which are highly homogenous to the ones identified in the USA, suggesting that the bovine influenza virus likely circulates widely and evolves slowly in the world.
Related JoVE Video
Tet-mediated formation of 5-hydroxymethylcytosine in RNA.
J. Am. Chem. Soc.
PUBLISHED: 08-07-2014
Show Abstract
Hide Abstract
Oxidation of 5-methylcytosine in DNA by ten-eleven translocation (Tet) family of enzymes has been demonstrated to play a significant role in epigenetic regulation in mammals. We found that Tet enzymes also possess the activity of catalyzing the formation of 5-hydroxymethylcytidine (5-hmrC) in RNA in vitro. In addition, the catalytic domains of all three Tet enzymes as well as full-length Tet3 could induce the formation of 5-hmrC in human cells. Moreover, 5-hmrC was present at appreciable levels (?1 per 5000 5-methylcytidine) in RNA of mammalian cells and tissues. Our results suggest the involvement of this oxidation in RNA biology.
Related JoVE Video
A school-based study of irritable bowel syndrome in medical students in beijing, china: prevalence and some related factors.
Gastroenterol Res Pract
PUBLISHED: 08-04-2014
Show Abstract
Hide Abstract
Purpose. To investigate the prevalence and some related factors about irritable bowel syndrome (IBS) in medical students. Methods. A cross-sectional study was carried out from February 2014 to Jun 2014 in Beijing University of Chinese Medicine, Beijing, China. All participants were asked to completed self-administered questionnaires. Results. Seven hundred and sixty-seven medical students (23.26 ± 2.88 years, 25.6% males) completed the survey. The prevalence of IBS was 33.3%, with a high prevalence in women (36.1%). Among the IBS patients, 112 cases were IBS-M (43.9%) and 77.6% had moderately severe IBS. There were no statistical differences between control group and IBS patients in anxiety and depression scores (P > 0.05). The total score of Pittsburgh sleep quality index (PSQI) was significantly higher for medical students with IBS and 35.5% of IBS patients had severe sleep disorder; the scores of child trauma questionnaire (CTQ) and student-life stress inventory (SLSI) were also higher in IBS patients. Sex and sleep disorder were independently associated with IBS (OR, 1.914, 95%CI, 1.281-2.860; OR, 1.143, 95%CI, 1.074-1.216). Conclusion. Our study has many valuable findings and they may provide valuable suggestions for the necessary intervention and treatment measures towards medical students.
Related JoVE Video
Photochemical transformation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in surface coastal waters: effects of chloride and ferric ions.
Mar. Pollut. Bull.
PUBLISHED: 08-04-2014
Show Abstract
Hide Abstract
The effects of several aquatic environmental factors on the photochemical transformation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) have been investigated. Ferric ion (Fe(III)) has been found to promote the phototransformation of BDE-47, and this process is further enhanced with the added chloride ion (Cl(-)), while it is suppressed with increasing pH. Electron spin resonance results show that the formation of hydroxyl radical, and the added Cl(-) could influence the generation of hydroxyl radical in Fe(III) solution. Hence, Cl(-) enhances the phototransformation of BDE-47 most probably because of the reaction with Fe(III) species under irradiation, yielding hydroxyl and chloride radicals. These radicals can not only decompose PBDEs, but also lead to their photodebromination and photochlorination. These results indicate that the aquatic environmental factors and Cl(-) in particular played an important role in the photochemical transformation process of PBDEs, providing insight into the likely fate of PBDEs in the marine environment.
Related JoVE Video
Piezotronic interface engineering on ZnO/Au-based Schottky junction for enhanced photoresponse of a flexible self-powered UV detector.
ACS Appl Mater Interfaces
PUBLISHED: 08-01-2014
Show Abstract
Hide Abstract
Exploiting piezoelectric effect to engineer material interface has been confirmed as a promising way to optimize the performance of optoelectronic devices. Here, by using this effect, we have greatly improved the photoresponse of the fabricated ZnO/Au Schottky junction based self-powered UV detector. A 440% augment of photocurrent, together with 5× increased sensitivity, was obtained when the device was subjected to a 0.580% tensile strain. The enhancement can be attributed to the facility separation and extraction of photoexcites due to the formation of the stronger and expanding built-in field, which is a result of charge redistribution induced by piezoelectric polarization at the ZnO/Au interface. This study not only can strengthen the understanding of piezoelectric effects on energy devices but also can be extended to boost performances of optoelectronic devices made of piezoelectric semiconductor materials.
Related JoVE Video
Early prediction of skin viability using visible diffuse reflectance spectroscopy and autofluorescence spectroscopy.
Plast. Reconstr. Surg.
PUBLISHED: 07-29-2014
Show Abstract
Hide Abstract
Accurate and early prediction of skin flap viability is vitally important in reconstructive surgery. To the best of the authors' knowledge, this is the first pilot study to evaluate the simultaneous use of both visible diffuse reflectance and autofluorescence spectroscopy on a reverse MacFarlane rat dorsal skin flap model in the early prediction of skin viability.
Related JoVE Video
Bioelectrochemical enhancement of anaerobic methanogenesis for high organic load rate wastewater treatment in a up-flow anaerobic sludge blanket (UASB) reactor.
Sci Rep
PUBLISHED: 07-25-2014
Show Abstract
Hide Abstract
A coupling process of anaerobic methanogenesis and electromethanogenesis was proposed to treat high organic load rate (OLR) wastewater. During the start-up stage, acetate removal efficiency of the electric-biological reactor (R1) reached the maximization about 19 percentage points higher than that of the control anaerobic reactor without electrodes (R2), and CH4 production rate of R1 also increased about 24.9% at the same time, while additional electric input was 1/1.17 of the extra obtained energy from methane. Coulombic efficiency and current recorded showed that anodic oxidation contributed a dominant part in degrading acetate when the metabolism of methanogens was low during the start-up stage. Along with prolonging operating time, aceticlastic methanogenesis gradually replaced anodic oxidation to become the main pathway of degrading acetate. When the methanogens were inhibited under the acidic conditions, anodic oxidation began to become the main pathway of acetate decomposition again, which ensured the reactor to maintain a stable performance. FISH analysis confirmed that the electric field imposed could enrich the H2/H(+)-utilizing methanogens around the cathode to help for reducing the acidity. This study demonstrated that an anaerobic digester with a pair of electrodes inserted to form a coupling system could enhance methanogenesis and reduce adverse impacts.
Related JoVE Video
Comparative analysis of h&e and prussian blue staining in a mouse model of cerebral microbleeds.
J. Histochem. Cytochem.
PUBLISHED: 07-25-2014
Show Abstract
Hide Abstract
Cerebral microbleeds are microscopic hemorrhages with deposits of blood products in the brain, which can be visualized with MRI and are implicated in cerebrovascular diseases. Hematoxylin and eosin (H&E) and Perl's Prussian blue are popular staining methods used to localize cerebral microbleeds in pathology. This paper compared these two staining techniques in a mouse model of cerebral microbleeds. We used lipopolysaccharide (LPS) to induce cerebral microhemorrhages. C57B6 mice were treated with LPS (5 mg/kg, i.p.) or vehicle at baseline and at 24 hr. The brains were extracted 48 hr after the first injection and adjacent coronal sections were stained with H&E and Prussian blue to compare the effectiveness of the two staining techniques. H&E-positive stains were increased with LPS treatment and were correlated with grossly visible microhemorrhages on the brain surface; Prussian blue-positive stains, by comparison, showed no significant increase with LPS treatment and did not correlate with either H&E-positive stains or surface microhemorrhages. H&E staining is thus a more reliable indicator of acute bleeding events induced by LPS in this model within a short time span.
Related JoVE Video
A clinical survey of common avian infectious diseases in China.
Avian Dis.
PUBLISHED: 07-25-2014
Show Abstract
Hide Abstract
Multiple common avian infectious diseases (CAIDs), namely, avian infectious diseases excluding highly pathogenic avian influenza and Newcastle disease, such as avian salmonellosis and coccidiosis, cause huge economic loss in poultry production and are of great significance in public health. However, they are usually not covered in the systems for reporting of animal diseases. Consequently, the distribution of CAIDs is not clear in many countries. Here, we report a clinical survey of CAIDs in China based on clinical diagnosis of eight veterinary clinics in 2011 and 2012. This survey provided the distribution data of viral, bacterial, and parasitic CAIDs in different types of avian flocks, seasons, and regions, data that are of great value in the research, prevention, and control of poultry diseases. This survey suggested that avian colibacillosis, infectious serositis in ducks caused by Riemerella anatipestifer, avian salmonellosis, fowl cholera, avian mycoplasmosis, avian aspergillosis, coccidiosis, low pathogenic avian influenza, infectious bronchitis, infectious bursal disease, and infectious laryngotracheitis are likely to be prevalent in the poultry in China.
Related JoVE Video
Exenatide can inhibit calcification of human VSMCs through the NF-kappaB/RANKL signaling pathway.
Cardiovasc Diabetol
PUBLISHED: 07-21-2014
Show Abstract
Hide Abstract
BackgroundArterial calcification is an important pathological change of diabetic vascular complication. Osteoblastic differentiation of vascular smooth muscle cells (VSMCs) plays an important cytopathologic role in arterial calcification. The glucagon-like peptide-1 receptor agonists (GLP-1RA), a novel type of antidiabetic drugs, exert cardioprotective effects through the GLP-1 receptor (GLP-1R). However, the question of whether or not GLP-1RA regulates osteoblastic differentiation and calcification of VSMCs has not been answered, and the associated molecular mechanisms have not been examined.MethodsCalcifying VSMCs (CVSMCs) were isolated from cultured human arterial smooth muscle cells through limiting dilution and cloning. The extent of matrix mineralization was measured by Alizarin Red S staining. Protein expression and phosphorylation were detected by Western blot. Gene expression of receptor activator of nuclear factor-¿B ligand (RANKL) was silenced by small interference RAN (siRNA).ResultsExenatide, an agonist of GLP-1 receptor, attenuated ß-glycerol phosphate (ß-GP) induced osteoblastic differentiation and calcification of human CVSMCs in a dose- and time-dependent manner. RANKL siRNA also inhibited osteoblastic differentiation and calcification. Exenatide decreased the expression of RANKL in a dose-dependent manner. 1,25 vitD3 (an activator of RANKL) upregulated, whereas BAY11-7082 (an inhibitor of NF-¿B) downregulated RANKL, alkaline phosphatase (ALP), osteocalcin (OC), and core binding factor ¿1 (Runx2) protein levels and reduced mineralization in human CVSMCs. Exenatide decreased p-NF-¿B and increased p-AMPK¿ levels in human CVSMCs 48 h after treatment. Significant decrease in p-NF-¿B (p-Ser276, p-Ser536) level was observed in cells treated with exenatide or exenatide¿+¿BAY11-7082.ConclusionGLP-1RA exenatide can inhibit human VSMCs calcification through NF-¿B/ RANKL signaling.
Related JoVE Video
Enhanced photoelectrochemical property of ZnO nanorods array synthesized on reduced graphene oxide for self-powered biosensing application.
Biosens Bioelectron
PUBLISHED: 07-16-2014
Show Abstract
Hide Abstract
We have realized the direct synthesis of ZnO nanorods (ZnO NRs) array on reduced graphene layer (rGO), and demonstrated the enhanced photoelectrochemical (PEC) property of the rGO/ZnO based photoanode under UV irradiation compared with the pristine ZnO NRs array. The introduction of the rGO layer resulted in a favorable energy band structure for electron migration, which finally led to the efficient photoinduced charge separation. Such nanostructure was subsequently employed for self-powered PEC biosensing of glutathione in the condition of 0V bias, with a linear range from 10 to 200µM, a detection limit of 2.17µM, as well as excellent selectivity, reproducibility and stability. The results indicated the rGO/ZnO nanostructure is a competitive candidate in the PEC biosensing field.
Related JoVE Video
Negative Regulation of DsbA-L Gene Expression by the Transcription Factor Sp1.
Diabetes
PUBLISHED: 07-14-2014
Show Abstract
Hide Abstract
Disulfide-bond A oxidoreductase-like protein (DsbA-L) possesses beneficial effects such as promoting adiponectin multimerization and stability, increasing insulin sensitivity, and enhancing energy metabolism. The expression level of DsbA-L is negatively correlated with obesity in mice and humans, but the underlying mechanisms remain unknown. To address this question, we generated reporter gene constructs containing the promoter sequence of the mouse DsbA-L gene. Deletion analysis showed that the proximal promoter of mouse DsbA-L is located between -186 and -34 bp relative to the transcription start site. In silico analysis identified a putative Sp1 transcription factor binding site in the first intron of the DsbA-L gene. Electrophoretic mobility shift assay and chromatin immunoprecipitation analysis indicated that Sp1 bound to this intron region in vitro and in intact cells. Overexpression of Sp1 or suppressing Sp1 expression by siRNA reduced or increased DsbA-L promoter activity, respectively. The binding activity of Sp1 was gradually decreased during 3T3-L1 cell differentiation and was significantly increased in adipose tissues of obese mice. Our results identify Sp1 as an inhibitor of DsbA-L gene transcription, and the Sp1-mediated inhibition of DsbA-L gene expression may provide a mechanism underlying obesity-induced adiponectin downregulation and insulin resistance.
Related JoVE Video
Enhanced near-infrared to visible upconversion nanoparticles of Ho³?-Yb³?-F? tri-doped TiO? and its application in dye-sensitized solar cells with 37% improvement in power conversion efficiency.
Inorg Chem
PUBLISHED: 07-14-2014
Show Abstract
Hide Abstract
New near-infrared (NIR)-to-green upconversion nanoparticles of Ho(3+)-Yb(3+)-F(-) tridoped TiO2 (UC-F-TiO2) were designed and fabricated via the hydrosol-hydrothermal method. Under 980 nm NIR excitation, UC-F-TiO2 emit strong green upconversion fluorescence with three emission bands at 543, 644, and 751 nm and convert the NIR light in situ to the dye-sensitive visible light that could effectively reduce the distance between upconversion materials and sensitizers; thus, they minimize the loss of the converted light. Our results show that this UC-F-TiO2 offers excellent opportunities for the other types of solar cells applications, such as organic solar cells, c-Si solar cells, multijunction solar cells, and so on. When integrating the UC-F-TiO2 into dye-sensitized solar cells (DSSCs), superior total energy conversion efficiency was achieved. Under AM1.5G light, open-circuit voltage reached 0.77 ± 0.01 V, short-circuit current density reached 21.00 ± 0.69 mA cm(-2), which resulted in an impressive overall energy conversion efficiency of 9.91 ± 0.30%, a 37% enhancement compared to DSSCs with pristine TiO2 photoanode.
Related JoVE Video
Correlated electrical and optical analysis of single nanoparticles and biomolecules on a nanopore-gated optofluidic chip.
Nano Lett.
PUBLISHED: 07-11-2014
Show Abstract
Hide Abstract
The analysis of individual biological nanoparticles has significantly advanced our understanding of fundamental biological processes but is also rapidly becoming relevant for molecular diagnostic applications in the emerging field of personalized medicine. Both optical and electrical methods for the detection and analysis of single biomolecules have been developed, but they are generally not used in concert and in suitably integrated form to allow for multimodal analysis with high throughput. Here we report on a dual-mode electrical and optical single-nanoparticle sensing device with capabilities that would not be available with each technique individually. The new method is based on an optofluidic chip with an integrated nanopore that serves as a smart gate to control the delivery of individual nanoparticles to an optical excitation region for ensemble-free optical analysis in rapid succession. We demonstrate electro-optofluidic size discrimination of fluorescent nanobeads, electro-optical detection of single fluorescently labeled influenza viruses, and the identification of single viruses within a mixture of equally sized fluorescent nanoparticles with up to 100% fidelity.
Related JoVE Video
Systematic reviews on reports of hip fractures in Web of Science: a bibliometric analysis of publication activity.
Chin. Med. J.
PUBLISHED: 07-03-2014
Show Abstract
Hide Abstract
The objective of this study was to analyze the trend in the publication of systematic reviews on hip fractures through a bibliometric approach.
Related JoVE Video
High-valent chromium-oxo complex acting as an efficient catalyst precursor for selective two-electron reduction of dioxygen by a ferrocene derivative.
Inorg Chem
PUBLISHED: 07-02-2014
Show Abstract
Hide Abstract
Efficient catalytic two-electron reduction of dioxygen (O2) by octamethylferrocene (Me8Fc) produced hydrogen peroxide (H2O2) using a high-valent chromium(V)-oxo corrole complex, [(tpfc)Cr(V)(O)] (tpfc = tris(pentafluorophenyl)corrole) as a catalyst precursor in the presence of trifluoroacetic acid (TFA) in acetonitrile (MeCN). The facile two-electron reduction of [(tpfc)Cr(V)(O)] by 2 equiv of Me8Fc in the presence of excess TFA produced the corresponding chromium(III) corrole [(tpfc)Cr(III)(OH2)] via fast electron transfer from Me8Fc to [(tpfc)Cr(V)(O)] followed by double protonation of [(tpfc)Cr(IV)(O)](-) and facile second-electron transfer from Me8Fc. The rate-determining step in the catalytic two-electron reduction of O2 by Me8Fc in the presence of excess TFA is inner-sphere electron transfer from [(tpfc)Cr(III)(OH2)] to O2 to produce the chromium(IV) superoxo species [(tpfc)Cr(IV)(O2(•-))], followed by fast proton-coupled electron transfer reduction of [(tpfc)Cr(IV)(O2(•-))] by Me8Fc to yield H2O2, accompanied by regeneration of [(tpfc)Cr(III)(OH2)]. Thus, although the catalytic two-electron reduction of O2 by Me8Fc was started by [(tpfc)Cr(V)(O)], no regeneration of [(tpfc)Cr(V)(O)] was observed in the presence of excess TFA, regardless of the tetragonal chromium complex being to the left of the oxo wall. In the presence of a stoichiometric amount of TFA, however, disproportionation of [(tfpc)Cr(IV)(O)](-) occurred via the protonated species [(tpfc)Cr(IV)(OH)] to produce [(tpfc)Cr(III)(OH2)] and [(tpfc)Cr(V)(O)].
Related JoVE Video
Efficient and durable hydrogen evolution electrocatalyst based on nonmetallic nitrogen doped hexagonal carbon.
Sci Rep
PUBLISHED: 07-01-2014
Show Abstract
Hide Abstract
The feasibility of renewable energy technology, hydrogen production by water electrolysis, depends on the design of efficient and durable electrocatalyst composed of earth-abundant elements. Herein, a highly active and stable nonmetallic electrocatalyst, nitrogen doped hexagonal carbon (NHC), was developed for hydrogen production. It exhibited high activity for hydrogen evolution with a low overpotential of only 65?mV, an apparent exchange current density of 5.7 × 10(-2)?mA cm(-2) and a high hydrogen production rate of 20.8?mL cm(-2) h(-1) at -0.35?V. The superior hydrogen evolution activity of NHC stemmed from the intrinsic electrocatalytic property of hexagonal nanodiamond, the rapid charge transfer and abundance of electrocatalytic sites after nitrogen doping. Moreover, NHC was stable in a corrosive acidic solution during electrolysis under high current density.
Related JoVE Video
Clinical outcome in male patients with detrusor overactivity with impaired contractility.
Int Neurourol J
PUBLISHED: 06-29-2014
Show Abstract
Hide Abstract
To review the clinical outcomes of patients with voiding dysfunction who have detrusor overactivity with impaired contractility (DOIC) diagnosed with urodynamic studies.
Related JoVE Video
microRNA 490-3P enhances the drug-resistance of human ovarian cancer cells.
J Ovarian Res
PUBLISHED: 06-28-2014
Show Abstract
Hide Abstract
MicroRNAs (miRNAs) are non-coding, single-stranded small RNAs that regulate gene expression negatively, which is involved in fundamental cellular processes. In this study, we investigated the role of miR-490-3P in the development of drug resistance in ovarian cancer cells.
Related JoVE Video
A high-pressure bi-directional cycloid rotor flowmeter.
Sensors (Basel)
PUBLISHED: 06-27-2014
Show Abstract
Hide Abstract
The measurement of the flow rate of various liquids and gases is critical in industrial automation. Rotary positive displacement meters (rotary PD meters) are highly accurate flowmeters that are widely employed in engineering applications, especially in custody transfer operations and hydraulic control systems. This paper presents a high pressure rotary PD meter containing a pair of internal cycloid rotors. It has the advantages of concise structure, low pressure loss, high accuracy and low noise. The curve of the internal rotor is designed as an equidistant curtate epicycloid curve with the external rotor curve as its conjugate. The calculation method used to determine the displacement of the cycloid rotor flowmeter is discussed. A prototype was fabricated, and experiments were performed to confirm measurements over a flow range of 1-100 L/min with relative errors of less than ±0.5%. The pressure loss through the flowmeter was about 3 bar at a flow rate of 100 L/min.
Related JoVE Video
DABCO-based ionic liquids: recyclable catalysts for aza-Michael addition of ?,?-unsaturated amides under solvent-free conditions.
J. Org. Chem.
PUBLISHED: 06-27-2014
Show Abstract
Hide Abstract
An array of novel 1,4-diazobicyclo[2.2.2]octane (DABCO) based ionic liquids were developed and used as recyclable catalysts for the aza-Michael addition at room temperature without any organic solvent. [DABCO-PDO][OAc] was found to be the most efficient catalyst, and the amount of catalyst was only 10 mol %. Various amines reacted with a wide range of ?,?-unsaturated amides, smoothly affording target products in good to excellent yields within hours. Moreover, the catalyst could be reused up to eight times, still maintaining a high catalytic activity. Finally, a plausible mechanism was proposed. FTIR and computational chemistry were used to verify the catalytic mechanism.
Related JoVE Video
Constructing all carbon nanotube hollow fiber membranes with improved performance in separation and antifouling for water treatment.
Environ. Sci. Technol.
PUBLISHED: 06-26-2014
Show Abstract
Hide Abstract
Manipulating carbon nanotubes (CNTs) through engineering into advanced membranes with superior performance for disinfection and decontamination of water shows great promise but is challenging. In this paper, a facile assembly of CNTs into novel hollow fiber membranes with tunable inner/outer diameters and structures is developed for the first time. These free-standing membranes composed entirely of CNTs feature a porosity of 86±5% and a permeation flux of about 460±50 L m(-2) h(-1) at a pressure differential of 0.04 MPa across the membrane. The randomly oriented interwoven structure of CNTs endows the membranes considerable resistance to pore blockage. Moreover, the adsorption capability of the CNT hollow fiber membranes, which is crucial in the efficient removal of small and trace contaminant molecules, is about 2 orders of magnitude higher than that of commercial polyvinylidene fluoride hollow fiber membranes. The unique advantage of the CNT hollow fiber membranes over other commercial membranes is that they can be in situ electrochemically regenerated after adsorption saturation.
Related JoVE Video
Tunable ultrathin mantle cloak via varactor-diode-loaded metasurface.
Opt Express
PUBLISHED: 06-13-2014
Show Abstract
Hide Abstract
We propose a tunable strategy for the ultrathin mantle cloak via metasurface. The tunable cloak is implemented by loading varactor diodes between two neighboring horizontal metallic strips which constitute the metasurface. We demonstrate that the varactor diodes enable the capacitive reactance of the metasurface to be tunable from -157 ? to -3 ? when the DC bias voltage is properly changed. The active metasurface is then explored to cloak conformally a conducting cylinder. Both numerical and experiment results show that the cloaking frequency can be continuously controlled from 2.3 GHz to 3.7 GHz by appropriately adjusting the bias voltage. The flexible tunability and good cloaking performance are further examined by the measured field distributions. The advanced features of tunability, low profile, and conformal ability of the ultrathin cloak pave the way for practical applications of cloaking devices.
Related JoVE Video
Recovery of Raman spectra with low signal-to-noise ratio using Wiener estimation.
Opt Express
PUBLISHED: 06-13-2014
Show Abstract
Hide Abstract
Raman spectroscopy is a powerful non-destructive technique for qualitatively and quantitatively characterizing materials. However, noise often obscures interesting Raman peaks due to the inherently weak Raman signal, especially in biological samples. In this study, we develop a method based on spectral reconstruction to recover Raman spectra with low signal-to-noise ratio (SNR). The synthesis of narrow-band measurements from low-SNR Raman spectra eliminates the effect of noise by integrating the Raman signal along the wavenumber dimension, which is followed by spectral reconstruction based on Wiener estimation to recover the Raman spectrum with high spectral resolution. Non-negative principal components based filters are used in the synthesis to ensure that most variance contained in the original Raman measurements are retained. A total of 25 agar phantoms and 20 bacteria samples were measured and data were used to validate our method. Four commonly used de-noising methods in Raman spectroscopy, i.e. Savitzky-Golay (SG) algorithm, finite impulse response (FIR) filtration, wavelet transform and factor analysis, were also evaluated on the same set of data in addition to the proposed method for comparison. The proposed method showed the superior accuracy in the recovery of Raman spectra from measurements with extremely low SNR, compared with the four commonly used de-noising methods.
Related JoVE Video
Photodegradation of 2,4-D induced by NO?(-) in aqueous solutions: the role of NO?.
J Environ Sci (China)
PUBLISHED: 06-10-2014
Show Abstract
Hide Abstract
To elucidate the effect of nitrite ion (NO?(-)) on the photodegradation of organic pollutants, a 300 W mercury lamp and Pyrex tubes restricting the transmission of wavelengths below 290 nm were used to simulate sunlight, and the photodegradation processes of 2,4-dichlorophenoxyacetic acid (2,4-D) with different concentrations of NO?(-) in freshwater and seawater were studied. The effect of reactive oxygen species (ROS) on the photolysis of 2,4-D was also demonstrated using electron paramagnetic resonance (EPR). The results indicated that the 2,4-D photolysis reaction followed the first-order kinetics in freshwater and seawater under different concentrations of NO?(-). Meanwhile, the photochemical reaction rate of 2,4-D increased with increasing concentration of NO?(-). When the concentration of NO?(-) was lower than 23 mg/L, the photodegradation rate of 2,4-D in seawater was higher than that in freshwater. However, when the concentration of NO?(-) was reached 230 mg/L, 2,4-D degradation slowed down in seawater. It was important to note that EPR spectra showed NO? radical was generated in the NO?(-) solution under simulated sunlight irradiation, indicating that 2,4-D photodegradation could be induced by NO?. These results show the key role of NO?(-) in photochemistry and are helpful for better understanding of the phototransformation of environmental contaminants in natural aquatic systems.
Related JoVE Video
Identification of the glucosyltransferase that converts hydroxymethyluracil to base J in the trypanosomatid genome.
J. Biol. Chem.
PUBLISHED: 06-02-2014
Show Abstract
Hide Abstract
O-linked glucosylation of thymine in DNA (base J) is an important regulatory epigenetic mark in trypanosomatids. ?-d-glucopyranosyloxymethyluracil (base J) synthesis is initiated by the JBP1/2 enzymes that hydroxylate thymine, forming 5-hydroxymethyluracil (hmU). hmU is then glucosylated by a previously unknown glucosyltransferase. A recent computational screen identified a possible candidate for the base J-associated glucosyltransferase (JGT) in trypanosomatid genomes. We demonstrate that recombinant JGT utilizes uridine diphosphoglucose to transfer glucose to hmU in the context of dsDNA. Mutation of conserved residues typically involved in glucosyltransferase catalysis impairs DNA glucosylation in vitro. The deletion of both alleles of JGT from the genome of Trypanosoma brucei generates a cell line that completely lacks base J. Reintroduction of JGT in the JGT KO restores J synthesis. Ablation of JGT mRNA levels by RNAi leads to the sequential reduction in base J and increased levels of hmU that dissipate rapidly. The analysis of JGT function confirms the two-step J synthesis model and demonstrates that JGT is the only glucosyltransferase enzyme required for the second step of the pathway. Similar to the activity of the related Ten-Eleven Translocation (TET) family of dioxygenases on 5mC, our studies also suggest the ability of the base J-binding protein enzymes to catalyze iterative oxidation of thymine in trypanosome DNA. Here we discuss the regulation of hmU and base J formation in the trypanosome genome by JGT and base J-binding protein.
Related JoVE Video
Electrochemiluminescence immunosensor for highly sensitive detection of 8-hydroxy-2'-deoxyguanosine based on carbon quantum dot coated Au/SiO2 core-shell nanoparticles.
Talanta
PUBLISHED: 05-30-2014
Show Abstract
Hide Abstract
An electrochemiluminescence (ECL) immunosensor using Pt electrode modified with carbon quantum dot (CQDs) coated Au/SiO2 core-shell nanoparticles was proposed for sensitive detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in this work. Rabbit anti-8-OHdG antibody was covalently bound to CQDs on the surface of Au/SiO2 core-shell nanoparticles. Through signal amplification of Au/SiO2 core-shell nanoparticles, 8-fold enhancement of the ECL signals was achieved. Under optimal conditions, a good linear range from 0.2 to 200 ng mL(-1) with a low detection limit of 0.085 ng mL(-1) (S/N=3) for 8-OHdG detection was obtained. Interfering substances tests showed that the corresponding ECL intensity (?ECL) of 8-OHdG is 8-18 times higher than that of guanine, uric acid (UA) and ascorbic acid, demonstrating its good selectivity for 8-OHdG detection. The ECL immunosensor exhibits long-term stability with a relative standard deviation (RSD) of 8.5% even after 16 cycles of continuous potential scans. The result of analytical detection of 8-OHdG in real samples was satisfactory. The proposed ECL immunosensor shows good performance with high sensitivity, specificity, repeatability, stability and provided a powerful tool for 8-OHdG monitoring in clinical samples.
Related JoVE Video
Quantitative mass spectrometry-based analysis of ?-D-glucosyl-5-hydroxymethyluracil in genomic DNA of Trypanosoma brucei.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 05-28-2014
Show Abstract
Hide Abstract
?-D-glucosyl-5-hydroxymethyluracil (base J) is a hyper-modified nucleobase found in the nuclear DNA of kinetoplastid parasites. With replacement of a fraction of thymine in DNA, J is localized primarily in telomeric regions of all organisms carrying this modified base. The biosynthesis of J occurs in two putative steps: first, a specific thymine in DNA is recognized and converted into 5-hydroxymethyluracil (5-HmU) by J-binding proteins (JBP1 and JBP2); a glucosyl transferase (GT) subsequently glucosylates the 5-HmU to yield J. Although several recent studies revealed the roles of internal J in regulating transcription in kinetoplastids, functions of telomeric J and proteins involved in J synthesis remain elusive. Assessing the functions of base J and understanding fully its biosynthesis necessitate the measurement of its level in cells and organisms. In this study, we reported a reversed-phase HPLC coupled with tandem mass spectrometry (LC-MS/MS) method, together with the use of a surrogate internal standard (?-D-glucosyl-5-hydroxymethyl-2'-deoxycytidine, 5-gHmdC), for the accurate detection of ?-D-glucosyl-5-hydroxymethyl-2'-deoxyuridine (dJ) in Trypanosoma brucei DNA. For comparison, we also measured the level of the precursor for dJ synthesis [i.e. 5-hydroxymethyl-2'-deoxyuridine (5-HmdU)]. We found that base J was not detectable in the JBP-null cells whereas it replaced approximately 0.5% thymine in wild-type cells, which was accompanied with a markedly decreased level of 5-HmdU in JBP1/JBP2-null strain relative to the wild-type strain. These results provided direct evidence supporting that JBP proteins play an important role in oxidizing thymidine to form 5-HmdU, which facilitated the generation of dJ. This is the first report about the application of LC-MS/MS for the quantification of base J. The analytical method built a solid foundation for dissecting the molecular mechanisms of J biosynthesis and assessing the biological functions of base J in the future.?
Related JoVE Video
Conductive upconversion Er,Yb-FTO nanoparticle coating to replace Pt as a low-cost and high-performance counter electrode for dye-sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 05-21-2014
Show Abstract
Hide Abstract
F-doped SnO2 (FTO) nanocrystals modified by Er and Yb with upconversion capability and excellent catalytic properties have been designed and fabricated as an economic replacement for Pt for use as the counter electrode (CE) in dye-sensitized solar cells. The cost of the UC-FTO counter electrode is only ?(1)/20th of that for Pt. The upconverted luminescence-mediated energy transfer and the superior catalytic property for I3(-)/I(-) circulation overpowered the slight degradation caused by increased CE/electrolyte interface resistance. A 23.9% enhancement in photocurrent was achieved with little degradation in photovoltage, resulting in a 9.12% increase in solar-to-electric power conversion efficiency. Near-infrared (NIR) light-to-electricity has been directly observed by SPS and IPCE characterizations, showing the effect of the upconversion counter electrode.
Related JoVE Video
Evaluation of avian influenza virus isolated from ducks as a potential live vaccine candidate against novel H7N9 viruses.
Vaccine
PUBLISHED: 05-10-2014
Show Abstract
Hide Abstract
Recent outbreaks of a novel H7N9 avian influenza virus in humans in China raise pandemic concerns and underscore an urgent need to develop effective vaccines. Theoretically, live influenza vaccines are of multiple advantages over traditional inactivated influenza vaccines to be used in a pandemic, because they can be produced rapidly, safely, and inexpensively. However, studies on live vaccines against the novel H7N9 virus are limited. In this study, we evaluated a potential live influenza vaccine candidate using an H7N3 avian influenza virus isolated from ducks with controls of two recombinant viruses generated through reverse genetics. The potential candidate could be produced efficiently using chicken embryonated eggs, and is homogenous to the novel H7N9 virus in their viral hemagglutinin genes. The potential candidate is likely low pathogenic to birds and mammals, and likely sensitive to oseltamivir and amantadine, as suggested by its genomic sequences. Its low pathogenicity was further supported through inoculation in mice, chicken embryonated eggs and chickens. Specific antibodies elicited in mice were detectable at least during the period between day 14 and day 56 after intranasal administration of the candidate for one time. Titers of the specific antibodies increased significantly with a boost intranasal administration or a higher inoculation dose. The induced specific antibodies were of substantial cross-reactivity with the novel H7N9 virus. These primary but promising evaluation data suggest that the duck influenza virus could be used as a potential live vaccine candidate, favorably through a prime-boost route, to mitigate the severity of the possible pandemic caused by the newly emerging H7N9 virus, and is valuable to be further evaluated.
Related JoVE Video
Operative versus nonoperative treatment in complex proximal humeral fractures.
Orthopedics
PUBLISHED: 05-10-2014
Show Abstract
Hide Abstract
This updated meta-analysis investigated whether operative treatment is superior to nonoperative treatment in complex proximal humeral fractures. The authors searched the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE. Randomized controlled trials that evaluated operative vs nonoperative treatment for exclusively 3- or 4-part proximal humeral fractures were considered. Six studies with a total of 287 patients who had proximal humeral fractures were included. According to the meta-analysis, no statistically significant differences were found between operative and nonoperative treatment in Constant-Murley shoulder scores (Constant scores); Disabilities of the Arm, Shoulder, and Hand scores; total complication events; mortality; infection; nonunion; avascular necrosis; osteoarthritis; redisplacement of fractures; or dislocation or resorption of tuberosity. For health-related quality of life, EuroQol-5D (EQ-5D) favored operative treatment, but 15D scores showed no significant difference. Compared with nonoperative treatment, open reduction and internal fixation required significantly more additional surgeries (risk ratio, 6.50; 95% confidence interval, 1.54-27.50; P=.01), and more penetrations into joint space occurred (risk ratio, 9.56; 95% confidence interval, 2.27-40.13; P=.002). The limited evidence suggests that no convincing findings support the use of either open reduction and internal fixation or hemiarthroplasty for the treatment of complex proximal humeral fractures. The findings of the current study should be interpreted cautiously because of the modest sample size and the short follow-up period.
Related JoVE Video
Effects of co-treatment with sulforaphane and autophagy modulators on uridine 5'-diphospho-glucuronosyltransferase 1A isoforms and cytochrome P450 3A4 expression in Caco-2 human colon cancer cells.
Oncol Lett
PUBLISHED: 04-25-2014
Show Abstract
Hide Abstract
Sulforaphane (SFN), which is highly enriched in cruciferous vegetables, has been investigated for its cancer chemopreventive properties and ability to induce autophagy. Uridine 5'-diphospho (UDP)-glucuronosyltransferase (UGT)1A induction is one of the mechanisms that is responsible for the cancer chemopreventive activity of SFN. The current study demonstrates that rapamycin may enhance the chemopreventive effects of SFN on Caco-2 cells; this may be partially attributed to nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2)- and human pregnane X receptor (hPXR)-mediated UGT1A1, UGT1A8 and UGT1A10 induction. These results indicate that targeting autophagy modulation may be a promising strategy for increasing the chemopreventive effects of SFN in cases of colon cancer.
Related JoVE Video
Lipoxin A4 suppresses the development of endometriosis in an ALX receptor-dependent manner via the p38 MAPK pathway.
Br. J. Pharmacol.
PUBLISHED: 04-18-2014
Show Abstract
Hide Abstract
Lipoxins can function as endogenous 'breaking signals' in inflammation and play important roles in the progression of endometriosis. In this study, we further investigated the molecular mechanism by which lipoxin A4 (LXA4 ) suppresses the development of endometriosis.
Related JoVE Video
Exploring and exploiting dynamic noncovalent chemistry for effective surface modification of nanoscale metal-organic frameworks.
ACS Appl Mater Interfaces
PUBLISHED: 04-11-2014
Show Abstract
Hide Abstract
Surface properties determine, to a great extent, the biologically relevant functions of various kinds of nanosized materials. Although the modification of the surface of traditional inorganic or polymeric nanoparticles can be routinely achieved through covalent or noncovalent manner or both, the surface modification of nanoscale metal-organic frameworks (nano-MOFs) is extremely challenging because of their rapid degradation in aqueous environments. In this work, we systematically studied the synergistic and dynamic noncovalent interactions between fluorescent probes and iron(III) carboxylate nano-MOFs (i.e., MIL-101-NH2 (Fe), one of the most prevalent MOFs used in drug delivery and imaging). We further examined the interplay between the surface binding of fluorescent probes and the degradation of MIL-101-NH2 (Fe) in aqueous medium. It was demonstrated that the surface binding of probes is not only of high affinity but also dynamic and nonsheddable, even during the degradation, a feature that is essentially different from the covalent conjugation. Subsequently, we developed a unique and straightforward strategy for the surface modification of MIL-101-NH2 (Fe) with polymer by exploiting the synergy of noncovalent interactions between functionalized copolymers and MIL-101-NH2 (Fe). We demonstrated that the binding of polymers onto MIL-101-NH2 (Fe) surface was very effective in aqueous solution and surprisingly nonsheddable during the process of degradation. Surface polymers can creep on the surface of MIL-101-NH2 (Fe), in a dynamic and real-time manner, to the new sites formed immediately after the degradation. In addition, the stability of MIL-101-NH2 (Fe) particles in aqueous environments can be improved to some extent by the surface polymer coating. The results presented herein constitute an important innovation for surface engineering of nano-MOFs, which would benefit the application of nano-MOFs as delivery systems in aqueous systems.
Related JoVE Video
Complete mitochondrial genome of Red-rumped Swallow, Cecropis daurica (Passeriformes: Hirundinidae).
Mitochondrial DNA
PUBLISHED: 04-09-2014
Show Abstract
Hide Abstract
Abstract The complete mitochondrial genome of the Cecropis daurica was determined by using a PCR-based method. The complete mitochondrial DNA of this swallow was 17,949?bp in length, including 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and 2 control regions. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The gene arrangement of the Cecropis daurica was similar to that found in other passerines. Base composition of the heavy strain was A (30.5%), T (23.0%), C (32.1%) and G (14.3%) with the A?+?T bias of 53.5%.
Related JoVE Video
Functional and molecular features of the calmodulin-interacting protein IQCG required for haematopoiesis in zebrafish.
Nat Commun
PUBLISHED: 04-04-2014
Show Abstract
Hide Abstract
We previously reported a fusion protein NUP98-IQCG in an acute leukaemia, which functions as an aberrant regulator of transcriptional expression, yet the structure and function of IQCG have not been characterized. Here we use zebrafish to investigate the role of iqcg in haematopoietic development, and find that the numbers of haematopoietic stem cells and multilineage-differentiated cells are reduced in iqcg-deficient embryos. Mechanistically, IQCG binds to calmodulin (CaM) and acts as a molecule upstream of CaM-dependent kinase IV (CaMKIV). Crystal structures of complexes between CaM and IQ domain of IQCG reveal dual CaM-binding footprints in this motif, and provide a structural basis for a higher CaM-IQCG affinity when deprived of calcium. The results collectively allow us to understand IQCG-mediated calcium signalling in haematopoiesis, and propose a model in which IQCG stores CaM at low cytoplasmic calcium concentrations, and releases CaM to activate CaMKIV when calcium level rises.
Related JoVE Video
Residues and dissipation of trifloxystrobin and its metabolite in tomatoes and soil.
Environ Monit Assess
PUBLISHED: 03-28-2014
Show Abstract
Hide Abstract
A simple residue analytical method using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for the determination of trifloxystrobin and its metabolite trifloxystrobin acid (CGA321113) in tomato and soil was developed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of detection were 0.0005 mg/kg for trifloxystrobin and 0.001 mg/kg for trifloxystrobin acid, respectively. The average recoveries in tomato and soil ranged from 73-99 % for trifloxystrobin and 75-109 % for trifloxystrobin acid, with relative standard deviations below 15 %. The method was then used to study the dissipation and residues in tomato and soil. The dissipation half-lives of trifloxystrobin in tomato were 2.9 days (Beijing) and 5.4 days (Shandong), while in soil were 1.9 days (Beijing) and 3.0 days (Shandong), respectively. The final results showed that the major residue compound was trifloxystrobin in tomato whereas it was its metabolite, trifloxystrobin acid, in soil. The final residues of total trifloxystrobin (including trifloxystrobin acid) were below the EU maximum residue limit of 0.5 mg kg(-1) in tomato 3 days after the treatment.
Related JoVE Video
Photoswitchable formation of a DNA interstrand cross-link by a coumarin-modified nucleotide.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 03-19-2014
Show Abstract
Hide Abstract
A coumarin-modified pyrimidine nucleoside (1) has been synthesized using a Cu(I)-catalyzed click reaction and incorporated into oligodeoxynucleotides (ODNs). Interstrand cross-links are produced upon irradiation of ODNs containing 1 at 350?nm. Cross-linking occurs through a [2+2] cycloaddition reaction with the opposing thymidine, 2'-deoxycytidine, or 2'-deoxyadenosine. A much higher reactivity was observed with dT than dC or dA. Irradiation of the dT-1 and dC-1 cross-linked products at 254?nm leads to a reversible ring-opening reaction, while such phenomena were not observed with dA-1 adducts. The reversible reaction is ultrafast and complete within 50-90?s. Consistent photoswitching behavior was observed over 6 cycles of irradiation at 350?nm and 254?nm. To the best of our knowledge, this is the first example of photoswitchable interstrand cross-linking formation induced by a modified pyrimidine nucleoside.
Related JoVE Video
Reduction of acute toxicity and genotoxicity of dye effluent using Fenton-coagulation process.
J. Hazard. Mater.
PUBLISHED: 03-11-2014
Show Abstract
Hide Abstract
Dye wastewater exhibits significant ecotoxicity even though its physico-chemical parameters meet the discharge standards. In this work, the acute toxicity and genotoxicity of dye effluent were tested, and the Fenton-coagulation process was carried out to detoxify this dye effluent. The acute toxicity was evaluated according to the mortality rate of zebrafish, and genotoxicity was evaluated by micronucleus (MN) and comet assays. Removal of color and chemical oxygen demand (COD) was also investigated. The results indicated that the dye effluent showed strong acute toxicity and genotoxicity to zebrafish. After 4h of treatment by Fenton-coagulation process, the dye effluent exhibited no significant acute toxicity and genotoxicity to zebrafish. In addition, its COD was less than 50mg/L, which met the discharge standard. It demonstrates that Fenton-coagulation process can comprehensively reduce the acute toxicity and genotoxicity as well as the COD of the dye effluent.
Related JoVE Video
Vitamin D Binding Protein Affects the Correlation of 25(OH)D and Frailty in the Older Men.
Int J Endocrinol
PUBLISHED: 02-19-2014
Show Abstract
Hide Abstract
Vitamin D binding protein (DBP) may alter the biologic activity of 25-hydroxyvitamin D [25(OH)D]. The objective of our present study was to determine the joint effect of serum 25(OH)D and DBP on the risk of frailty. Five hundred sixteen male participants aged 70 years or older were recruited in Changsha city and its surrounding area in Hunan province of China. Frailty was defined as the presence of at least three of the five following criteria: weakness, low physical activity, slow walking speed, exhaustion, and weight loss. Multivariate linear regression analysis was performed to assess the relationship between 25(OH)D and DBP levels. Odds ratios (ORs) for frailty were evaluated across quartiles of 25(OH)D and DBP levels, adjusted age, education, and body mass index. The results showed that participants in the lowest quartile of 25(OH)D and the highest quartile of DBP levels, the lowest quartile of 25(OH)D and the lowest quartile of DBP levels, and those in the the lower quartile of 25(OH)D and lowest quartile of DBP levels had significantly higher OR of being frail compared with those in the highest quartile of 25(OH)D and lowest quartile of DBP, with OR of 3.18 (95% CI: 1.46-4.56, P < 0.05), 2.63 (95% CI: 1.31-3.68, P < 0.01), and 2.52 (95% CI: 1.22-3.52, P < 0.05), respectively. The results indicate that the joint effect of serum 25(OH)D and DBP levels is associated with the risk of frailty, and serum DBP levels affects 25(OH)D-frailty relationship in the older men.
Related JoVE Video
Advanced treatment of refractory organic pollutants in petrochemical industrial wastewater by bioactive enhanced ponds and wetland system.
Ecotoxicology
PUBLISHED: 02-16-2014
Show Abstract
Hide Abstract
A large-scale combined ponds-wetland system was applied for advanced treatment of refractory pollutants in petrochemical industrial wastewater. The system was designed to enhance bioactivity and biological diversity, which consisted of anaerobic ponds (APs), facultative ponds (FPs), aerobic pond and wetland. The refractory pollutants in the petrochemical wastewater to be treated were identified as alkanes, chloroalkanes, aromatic hydrocarbons, and olefins, which were significantly degraded and transformed along with the influent flowing through the enhanced bioactive ponds-wetland system. 8 years of recent operational data revealed that the average removal rate of stable chemical oxygen demand (COD) was 42.7 % and that influent COD varied from 92.3 to 195.6 mg/L. Final effluent COD could reach 65.8 mg/L (average). COD removal rates were high in the APs and FPs and accounted for 75 % of the total amount removed. This result indicated that the APs and FPs degraded refractory pollutants through the facilitation of bacteria growth. The changes in the community structures of major microbes were assessed by 16SrDNA-denaturing gradient gel electrophoresis. The same analysis was used to identify the main bacterial function for the removal of refractory pollutants in the APs and FPs. The APs and FPs displayed similar microbial diversities, and some of the identified bacteria degraded and removed refractory pollutants. The overall results proved the applicability, stability, and high efficiency of the ponds-wetland system with enhanced bioactivity in the advanced removal of refractory pollutants from petrochemical industrial wastewater.
Related JoVE Video
The mammalian target of rapamycin signalling pathway is involved in osteoblastic differentiation of vascular smooth muscle cells.
Can J Cardiol
PUBLISHED: 02-13-2014
Show Abstract
Hide Abstract
Vascular calcification is a major risk factor for cardiovascular diseases. Osteoblastic differentiation of vascular smooth muscle cells (VSMCs) is a key step in vascular calcification, but the molecular mechanisms driving the differentiation remain elusive. In this study, the involvement of mammalian target of rapamycin (mTOR) signalling in osteoblastic differentiation of VSMCs is investigated.
Related JoVE Video
A code for RanGDP binding in ankyrin repeats defines a nuclear import pathway.
Cell
PUBLISHED: 01-22-2014
Show Abstract
Hide Abstract
Regulation of nuclear import is fundamental to eukaryotic biology. The majority of nuclear import pathways are mediated by importin-cargo interactions. Yet not all nuclear proteins interact with importins, necessitating the identification of a general importin-independent nuclear import pathway. Here, we identify a code that determines importin-independent nuclear import of ankyrin repeats (ARs), a structural motif found in over 250 human proteins with diverse functions. AR-containing proteins (ARPs) with a hydrophobic residue at the 13th position of two consecutive ARs bind RanGDP efficiently, and consequently enter the nucleus. This code, experimentally tested in 17 ARPs, predicts the nuclear-cytoplasmic localization of over 150 annotated human ARPs with high accuracy and is acquired by the most common familial melanoma-associated CDKN2A mutation, leading to nuclear accumulation of mutant p16ink4a. The RaDAR (RanGDP/AR) pathway represents a general importin-independent nuclear import pathway and is frequently used by AR-containing transcriptional regulators, especially those regulating NF-?B/p53.
Related JoVE Video
Adiponectin attenuates the osteoblastic differentiation of vascular smooth muscle cells through the AMPK/mTOR pathway.
Exp. Cell Res.
PUBLISHED: 01-20-2014
Show Abstract
Hide Abstract
Vascular calcification is common in patients with peripheral artery diseases and coronary artery diseases. The osteoblastic differentiation of vascular smooth muscle cells (VSMCs) contributes significantly to vascular calcification. Adiponectin has been demonstrated to exert a protective effect in osteoblastic differentiation of VSMCs through regulating mTOR activity. However, the upstream and downstream signaling molecules of adiponectin-regulated mTOR signaling have not been identified in VSMCs with osteoblastic differentiation. In this study, the VSMC differentiation model was established by beta-glycerophosphate (?-GP) induction. The mineralization was identified by Alizarin Red S staining. Protein expression and phosphorylation were detected by Western blot or immunofluorescence. Adiponectin attenuated osteoblastic differentiation and mineralization of ?-GP-treated VSMCs. Adiponectin inhibited osteoblastic differentiation of VSMCs through increasing the level of p-AMPK?. Pretreatment of VSMCs with AMPK inhibitor blocked while AMPK activator enhanced the effect of adiponectin on osteoblastic differentiation of VSMCs. Adiponectin upregulated TSC2 expression and downregulated mTOR and S6K1 phosphorylation in ?-GP-treated VSMCs. Adiponectin treatment significantly attenuates the osteoblastic differentiation and calcification of VSMCs through modulation of AMPK-TSC2-mTOR-S6K1 signal pathway.
Related JoVE Video
In situ transmission electron microscopy investigation on fatigue behavior of single ZnO wires under high-cycle strain.
Nano Lett.
PUBLISHED: 01-14-2014
Show Abstract
Hide Abstract
The fatigue behavior of ZnO nanowires (NWs) and microwires was systematically investigated with in situ transmission electron microscopy electromechanical resonance method. The elastic modulus and mechanical quality factors of ZnO wires were obtained. No damage or failure was found in the intact ZnO wires after resonance for about 10(8)-10(9) cycles, while the damaged ZnO NW under electron beam (e-beam) irradiation fractured after resonance for seconds. The research results will provide a useful guide for designing, fabricating, and optimizing electromechanical nanodevices based on ZnO nanomaterials, as well as future applications.
Related JoVE Video
Enhanced anaerobic fermentation with azo dye as electron acceptor: Simultaneous acceleration of organics decomposition and azo decolorization.
J Environ Sci (China)
PUBLISHED: 01-07-2014
Show Abstract
Hide Abstract
Accumulation of hydrogen during anaerobic processes usually results in low decomposition of volatile organic acids (VFAs). On the other hand, hydrogen is a good electron donor for dye reduction, which would help the acetogenic conversion in keeping low hydrogen concentration. The main objective of the study was to accelerate VFA composition through using azo dye as electron acceptor. The results indicated that the azo dye serving as an electron acceptor could avoid H2 accumulation and accelerate anaerobic digestion of VFAs. After adding the azo dye, propionate decreased from 2400.0 to 689.5mg/L and acetate production increased from 180.0 to 519.5mg/L. It meant that the conversion of propionate into acetate was enhanced. Fluorescence in situ hybridization analysis showed that the abundance of propionate-utilizing acetogens with the presence of azo dye was greater than that in a reference without azo dye. The experiments via using glucose as the substrate further demonstrated that the VFA decomposition and the chemical oxygen demand (COD) removal increased by 319.7mg/L and 23.3% respectively after adding the azo dye. Therefore, adding moderate azo dye might be a way to recover anaerobic system from deterioration due to the accumulation of H2 or VFAs.
Related JoVE Video
Anacardic acid enhances the proliferation of human ovarian cancer cells.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Anacardic acid (AA) is a mixture of 2-hydroxy-6-alkylbenzoic acid homologs. Certain antitumor activities of AA have been reported in a variety of cancers. However, the function of AA in ovarian cancer, to date, has remained unknown.
Related JoVE Video
Synthesis of convex hexoctahedral pt micro/nanocrystals with high-index facets and electrochemistry-mediated shape evolution.
J. Am. Chem. Soc.
PUBLISHED: 12-05-2013
Show Abstract
Hide Abstract
Systematic manipulation of nanocrystal shapes is prerequisite for revealing their shape-dependent physical and chemical properties. Here we successfully prepared a complex shape of Pt micro/nanocrystals: convex hexoctahedron (HOH) enclosed with 48 {15 5 3} high-index facets by electrochemical square-wave-potential (SWP) method. This shape is the last crystal single form that had not been achieved previously for face-centered-cubic (fcc) metals. We further realized the shape evolution of Pt nanocrystals with high-index facets from tetrahexahedron (THH) to the HOH, and finally to trapezohedron (TPH) by increasing either the upper (EU) or lower potential (EL). The shape evolution, accompanied by the decrease of low-coordinated kink atoms, can be correlated with the competitive interactions between preferentially oxidative dissolution of kink atoms at high EU and the redeposition of Pt atoms at the EL.
Related JoVE Video
Allergic conditions reduce the risk of glioma: a meta-analysis based on 128,936 subjects.
Tumour Biol.
PUBLISHED: 11-03-2013
Show Abstract
Hide Abstract
Many studies have investigated the association between the allergic conditions and the risk of glioma. However, the evidence is inadequate to draw robust conclusions because most studies were generally small and conducted in heterogeneous populations. To shed light on these inconclusive findings, we conducted a meta-analysis of studies relating the allergic conditions to the risk of glioma. We identified the relevant studies by searching ISI Web of Science, PubMed, EMBASE, Chinese National Knowledge Infrastructure (CNKI) databases, and Wanfang database by October 2013. We included studies that reported odds ratio (OR) or hazard ratio (HR) with its 95 % confidence interval (CI) for the association between the allergic condition and the risk of glioma. Eighteen independent publications, with 9,986 glioma cases and 118,950 controls, were included. Our results showed that allergic condition was reversely associated with the risk of glioma (OR?=?0.78, 95 % CI 0.73-0.83, P?
Related JoVE Video
[Early removal of the chest tube after lobectomies: a prospective randomized control study].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 10-05-2013
Show Abstract
Hide Abstract
To evaluate the feasibility and safety of early chest tube removal after lobectomies for lung diseases.
Related JoVE Video
Genetic incorporation of a 2-naphthol group into proteins for site-specific azo coupling.
Bioconjug. Chem.
PUBLISHED: 10-02-2013
Show Abstract
Hide Abstract
The 2-naphthol analogue of tyrosine, 2-amino-3-(6-hydroxy-2-naphthyl)propanoic acid (NpOH), has been genetically introduced into proteins in Escherichia coli . This is achieved through the directed evolution of orthogonal aminoacyl-tRNA synthetase/tRNA pairs that selectively charge the target amino acid in response to the amber stop codon, UAG. Moreover, chemoselective azo coupling reactions have been revealed between the 2-naphthol group and diazotized aniline derivatives that are substituted with an electron donating moiety. The coupling reactions required a very mild condition (pH 7) with great reaction rate (less than 2 h at 0 °C), high efficiency, and excellent selectivity.
Related JoVE Video
Vitamin D Controls Murine and Human Plasmacytoid Dendritic Cell Function.
J. Invest. Dermatol.
PUBLISHED: 09-06-2013
Show Abstract
Hide Abstract
Topical application of the vitamin D (VitD) analog calcipotriol is a highly effective standard treatment modality of psoriatic skin lesions. However, the immune modulatory effects of the treatment are incompletely understood. VitD is well known to induce tolerogenic responses in conventional dendritic cells (cDCs). Plasmacytoid DCs (pDCs) comprise a specialized, naturally occurring DC subset known to be important in autoimmune diseases including psoriasis. pDCs from the blood rapidly infiltrate psoriatic skin and are key to the initiation of the immune-mediated pathogenesis of the disease. We now demonstrate that pDCs express various proteins of the VitD receptor (VDR) pathway, including the VitD-metabolizing enzymes Cyp27B1 and Cyp24A1, and that VDR is transcriptionally active in pDCs. Moreover, VitD impairs the capacity of murine and human pDCs to induce T-cell proliferation and secretion of the T-helper 1 cytokine IFN?. The inhibitory effect of VitD is dependent on the expression of the VDR in the DCs. This study demonstrates that VitD signaling can act as a natural inhibitory mechanism on both cDCs and pDCs, which may instigate the development of VitD-based therapeutic applications for psoriasis and other inflammatory skin diseases.Journal of Investigative Dermatology advance online publication, 19 December 2013; doi:10.1038/jid.2013.501.
Related JoVE Video
The Involvement of RhoA and Wnt-5a in the Tumorigenesis and Progression of Ovarian Epithelial Carcinoma.
Int J Mol Sci
PUBLISHED: 08-29-2013
Show Abstract
Hide Abstract
Background: Ras homolog gene family member A (RhoA) is involved in Wnt-5a-induced migration of gastric and breast cancer cells. We investigated the roles of RhoA and Wnt-5a in ovarian carcinoma. Methods: RhoA and Wnt-5a mRNA and protein expression in normal fallopian tube epithelium, benign tumors, primary ovarian carcinomas, and metastatic omentum were quantified. RhoA or Wnt-5a was knocked down in OVCAR3 ovarian carcinoma cells using siRNAs and cell phenotype and expression of relevant molecules were assayed. Results: RhoA and Wnt-5a mRNA and protein expression were found to be significantly higher in metastatic omentum than in ovarian carcinomas, benign tumors, and normal fallopian tube epithelium (p < 0.05), and positively associated with differentiation and FIGO staging (stage I/II vs. stage III/IV) in ovarian carcinoma (p < 0.05). RhoA and Wnt-5a expression were positively correlated in ovarian carcinoma (p = 0.001, R2 = 0.1669). RhoA or Wnt-5a knockdown downregulated RhoA and Wnt-5a expression; reduced cell proliferation; promoted G1 arrest and apoptosis; suppressed lamellipodia formation, cell migration, and invasion; and reduced PI3K, Akt, p70S6k, Bcl-xL, survivin, and VEGF mRNA or protein expression. Conclusions: This is the first demonstration that RhoA and Wnt-5a are associated with ovarian carcinogenesis and apoptosis inhibition; there might be positive correlation between RhoA and Wnt-5a expression. RhoA is a potential tumorigenesis, differentiation, and progression biomarker in ovarian carcinoma.
Related JoVE Video
Employing bifunctional enzymes for enhanced extraction of bioactives from plants: flavonoids as an example.
J. Agric. Food Chem.
PUBLISHED: 08-09-2013
Show Abstract
Hide Abstract
A cost-effective and environmentally friendly approach was developed to improve the extraction of active ingredients from plants, in which a bifunctional enzyme was employed for not only facilitating cell wall degradation but also increasing the bioactivity of target compounds in the extract. In the aqueous extraction of flavonoids from Glycyrrhizae radix, Trichoderma viride cellulase, a commercial cell-wall-degrading enzyme, was found to efficiently deglycosylate liquiritin and isoliquiritin, which are of high content but low bioactivity, into their aglycones that have much higher physiological activities for dietary and medicinal uses. Under optimized conditions, the extraction yield of liquiritigenin and isoliquiritigenin aglycones reached 4.23 and 0.39 mg/g of dry weight (dw) with 6.51- and 3.55-fold increases, respectively. The same approach was expanded to the extraction of flavonoids from Scutellariae radix using Penicillium decumbens naringinase, where enhanced production of more bioactive bacalein and wogonin was achieved via enzymatic deglycosylation of bacalin and wogonoside.
Related JoVE Video

What is Visualize?

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

How does it work?

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

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

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