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Find video protocols related to scientific articles indexed in Pubmed.
Mild hypothermia for treatment of diffuse axonal injury: a quantitative analysis of diffusion tensor imaging.
Neural Regen Res
PUBLISHED: 09-11-2014
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Fractional anisotropy values in diffusion tensor imaging can quantitatively reflect the consistency of nerve fibers after brain damage, where higher values generally indicate less damage to nerve fibers. Therefore, we hypothesized that diffusion tensor imaging could be used to evaluate the effect of mild hypothermia on diffuse axonal injury. A total of 102 patients with diffuse axonal injury were randomly divided into two groups: normothermic and mild hypothermic treatment groups. Patient's modified Rankin scale scores 2 months after mild hypothermia were significantly lower than those for the normothermia group. The difference in average fractional anisotropy value for each region of interest before and after mild hypothermia was 1.32-1.36 times higher than the value in the normothermia group. Quantitative assessment of diffusion tensor imaging indicates that mild hypothermia therapy may be beneficial for patients with diffuse axonal injury.
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Genome-wide sequencing of small RNAs reveals a tissue-specific loss of conserved microRNA families in Echinococcus granulosus.
BMC Genomics
PUBLISHED: 08-29-2014
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MicroRNAs (miRNAs) are important post-transcriptional regulators which control growth and development in eukaryotes. The cestode Echinococcus granulosus has a complex life-cycle involving different development stages but the mechanisms underpinning this development, including the involvement of miRNAs, remain unknown.
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Exonuclease III-assisted cascade signal amplification strategy for label-free and ultrasensitive chemiluminescence detection of DNA.
Anal. Chem.
PUBLISHED: 08-20-2014
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Detection of ultralow concentrations of specific nucleic acid sequences is a central challenge in the early diagnosis of genetic diseases and biodefense applications. Herein, we report a simple and homogeneous chemiluminescence (CL) method for ultrasensitive DNA detection. It is based on the exonuclease III (Exo III)-assisted cascade signal amplification and the catalytic effect of G-quadruplex-hemin DNAzyme on the luminol-H2O2 CL system. A quadruplex-forming DNA probe hybridizes a hairpin DNA probe to construct a duplex DNA probe as recognition element. Upon sensing of target DNA, the recognition of target DNA and the duplex DNA probe triggers the Exo III cleavage process, accompanied by releasing target DNA and generating a new secondary target DNA fragment. The released target DNA and the secondary target DNA are recycled. Simultaneously, numerous quadruplex-forming sequences are liberated and bind hemin to yield G-quadruplex-hemin DNAzyme, which subsequently catalyze the luminol-H2O2 reaction to produce strong CL emission. This method exhibited a high sensitivity toward target DNA with a detection limit of 8 fM, which was about 100 times lower than that of the reported DNAzyme-based colorimetric system for DNA detection with Exo III-assisted cascade signal amplification. This method provides a simple, isothermal, and low-cost approach for sensitive detection of DNA and holds a great potential for early diagnosis in gene-related diseases.
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Berberine induces hERG channel deficiency through trafficking inhibition.
Cell. Physiol. Biochem.
PUBLISHED: 08-18-2014
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The human ether-a-go-go-related gene (hERG) encodes the ? subunit of the IKr, which plays an essential role in repolarization of action potentials. hERG channels are targeted by various pro-arrhythmic drugs. Berberine (BBR) was previously found to acutely inhibit hERG currents and prolong action potential duration. The present study aimed to determine long-term effects of BBR on the expression of 135kDa/155kDa hERG and the mechanism.
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Resveratrol suppresses oxidised low-density lipoprotein-induced macrophage apoptosis through inhibition of intracellular reactive oxygen species generation, LOX-1, and the p38 MAPK pathway.
Cell. Physiol. Biochem.
PUBLISHED: 08-11-2014
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Resveratrol (RSV) may have therapeutic potential for various diseases. Here we investigated the effect of RSV on oxidised low-density lipoprotein- (ox-LDL) induced apoptosis in RAW264.7 macrophages.
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Synergistic association of six well-characterized polymorphisms in three genes of the renin-angiotensin system with breast cancer among Han Chinese women.
J Renin Angiotensin Aldosterone Syst
PUBLISHED: 08-01-2014
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Breast cancer is the most common malignancy that is believed to be largely under genetic control. We therefore investigated both individual and interactive associations of six well-characterized polymorphisms in three genes of the renin-angiotensin system with breast cancer among Han Chinese women.
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Comparative study of the protective effects of terfenadine and amiodarone on barium chloride/aconitine-induced ventricular arrhythmias in rats: A potential role of terfenadine.
Mol Med Rep
PUBLISHED: 07-22-2014
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Terfenadine is a second generation histamine receptor antagonist which is widely used as a non?sedating antihistamine to relieve allergic responses. However, terfenadine has been associated with a number of side effects on cardiac electrical activities through blocking multiple ion channels in the heart, particularly K+ channels. Previous studies have also implied that terfenadine may have a potential antiarrhythmic effect; however, the electrophysiological influence by which terfenadine exerts its antiarrhythmic action remains elusive. Based on evidence from previous studies, it was hypothesized that the antiarrhythmic effect of terfenadine may be similar to that of amiodarone. The present study aimed to examine the effect of terfenadine on the QTc interval and on experimental ventricular arrhythmia in rats by comparing with that of amiodarone. The effect of terfenadine and amiodarone on the QTc interval was evaluated by comparison of multiple electrocardiograms. Barium chloride/aconitine was intraperitoneally injected to induce ventricular arrhythmias. Normal saline was administered to control rats. In comparison with normal saline, terfenadine and amiodarone similarly dose?dependently prolonged the QTc interval in rats. In the barium chloride/aconitine-induced ventricular arrhythmia model, terfenadine and amiodarone did not only similarly delay the onset time of arrhythmias induced by barium chloride (all P<0.05), but also increased the cumulative dosage of aconitine required to induce various arrhythmias (all P<0.05). Furthermore, the two drugs equivalently caused a significant decrease in the duration of ventricular tachycardia in comparison with the normal saline controls (all P<0.05). The present study suggested that terfenadine prolonged the QTc interval and decreased ventricular tachycardia duration. The potential protective effect of terfenadine in ventricular arrhythmia may be similar to that of amiodarone.
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Resveratrol protects vascular smooth muscle cells against high glucose-induced oxidative stress and cell proliferation in vitro.
Med Sci Monit Basic Res
PUBLISHED: 06-28-2014
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Resveratrol exhibits beneficial effects against numerous degenerative diseases at different stages of pathogenesis. This study investigated potential mechanisms and resveratrol effects on high glucose (HG)-induced oxidative stress (30 mM D-glucose, 30 min) and cell proliferation (30 mM D-glucose, 24 h) in vascular smooth muscle cells (VSMCs).
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Dithiaarsanes induce oxidative stress-mediated apoptosis in HL-60 cells by selectively targeting thioredoxin reductase.
J. Med. Chem.
PUBLISHED: 06-11-2014
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The selenoprotein thioredoxin reductase (TrxR) plays a pivotal role in regulating cellular redox homeostasis and has attracted increasing attention as a promising anticancer drug target. We report here that 2-(4-aminophenyl)-1,3,2-dithiarsinane (PAO-PDT, 4), a potent and highly selective small molecule inhibitor of TrxR, stoichiometrically binds to the C-terminal selenocysteine/cysteine pair in the enzyme in vitro and induces oxidative stress-mediated apoptosis in HL-60 cells. The molecular action of 4 in cells involves inhibition of TrxR, elevation of reactive oxygen species, depletion of cellular thiols, and activation of caspase-3. Knockdown of TrxR sensitizes the cells to 4 treatment, whereas overexpression of the functional enzyme alleviates the cytotoxicity, providing physiological relevance for targeting TrxR by 4 in cells. The simplicity of the structure and the presence of an easily manipulated amine group will facilitate the further development of 4 as a potential cancer chemotherapeutic agent.
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Activation of the phase II enzymes for neuroprotection by ginger active constituent 6-dehydrogingerdione in PC12 cells.
J. Agric. Food Chem.
PUBLISHED: 06-09-2014
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The cellular endogenous antioxidant system plays pivotal roles in counteracting or retarding the pathogenesis of many neurodegenerative diseases. Molecules with the ability to enhance the antioxidant defense thus are promising candidates for neuroprotective drugs. 6-Dehydrogingerdione (6-DG), one of the major components of dietary ginger, has received increasing attention due to its multiple pharmacological activities. However, how this pleiotropic molecule works on the neuronal system has not been studied. This paper reports that 6-DG efficiently scavenges various free radicals in vitro and displays remarkable cytoprotection against oxidative stress-induced neuronal cell damage in the neuron-like rat pheochromocytoma cell line, PC12 cells. Pretreatment of PC12 cells with 6-DG significantly up-regulates a panel of phase II genes as well as the corresponding gene products, such as glutathione, heme oxygenase,
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A paper-based chemiluminescence device for the determination of ofloxacin.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 06-05-2014
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Paper-based devices are biodegradable and have been used in diagnosis and environmental analysis field. In this work, a wax-printed paper-based analytical device combined with silver nanoparticles (AgNPs) catalyzed luminol chemiluminescence (CL) system for the determination of ofloxacin (OFLX) was presented. It was based on the enhancement of CL intensity of luminol-H2O2-OFLX system by AgNPs. Wax-printing fabrication technique was used to make the simple circle shaped paper device and large scale chips can be fabricated at the same time. Under the selected experimental conditions, a linear relationship was obtained between the CL intensity and the concentration of OFLX in the range from 1.0×10(-)(9)g/mL to 1.0×10(-)(6)g/mL with a detection limit of 3.0×10(-)(10)g/mL. This method has been successfully applied to the determination of OFLX in eyedrop samples.
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Highly sensitive fluorescence assay of T4 polynucleotide kinase activity and inhibition via enzyme-assisted signal amplification.
Anal. Biochem.
PUBLISHED: 05-17-2014
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DNA phosphorylation catalyzed by polynucleotide kinase (PNK) is an indispensable process in the repair, replication, and recombination of nucleic acids. Here, an enzyme-assisted amplification strategy was developed for the ultrasensitive monitoring activity and inhibition of T4 PNK. A hairpin oligonucleotide (hpDNA) was designed as a probe whose stem can be degraded from the 5' to 3' direction by lambda exonuclease (? exo) when its 5' end is phosphorylated by PNK. So, the 3' stem and loop part of hpDNA was released as an initiator strand to open a molecular beacon (MB) that was designed as a fluorescence reporter, leading to a fluorescence restoration. Then, the initiator strand was released again by the nicking endonuclease (Nt.BbvCI) to hybridize with another MB, resulting in a cyclic reaction and accumulation of fluorescence signal. Based on enzyme-assisted amplification, PNK activity can be sensitively and rapidly detected with a detection limit of 1.0×10(-4)U/ml, which is superior to those of most existing approaches. Furthermore, the application of the proposed strategy for screening PNK inhibitors also demonstrated satisfactory results. Therefore, it provided a promising platform for monitoring activity and inhibition of PNK as well as for studying the activity of other nucleases.
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Max-margin multiattribute learning with low-rank constraint.
IEEE Trans Image Process
PUBLISHED: 05-07-2014
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Attribute learning has attracted a lot of interests in recent years for its advantage of being able to model high-level concepts with a compact set of midlevel attributes. Real-world objects often demand multiple attributes for effective modeling. Most existing methods learn attributes independently without explicitly considering their intrinsic relatedness. In this paper, we propose max margin multiattribute learning with low-rank constraint, which learns a set of attributes simultaneously, using only relative ranking of the attributes for the data. By learning all the attributes simultaneously through low-rank constraint, the proposed method is able to capture their intrinsic correlation for improved learning; by requiring only relative ranking, the method avoids restrictive binary labels of attributes that are often assumed by many existing techniques. The proposed method is evaluated on both synthetic data and real visual data including a challenging video data set. Experimental results demonstrate the effectiveness of the proposed method.
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Epidemiology and control of echinococcosis in central Asia, with particular reference to the People's Republic of China.
Acta Trop.
PUBLISHED: 03-17-2014
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At least 270 million people (58% of the total population) are at risk of cystic echinococcosis (CE) in Central Asia including areas of Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan, Afghanistan, Iran, Pakistan and western China. The annual surgical incidence rate in Uzbekistan and Tadjikistan has been estimated to be as high as 25-27 cases/100,000 with the highest prevalence reaching 10% (range from 0.8 to 11.9%) in some Tibetan communities in western China. Echinococcus transmission in the region is largely associated with social factors including limited community knowledge of echinococcosis, small-scale household animal production, home killing of livestock, and the feeding of dogs with uncooked offal. Alveolar echinococcosis (AE) is also endemic in Central Asia and is recognized as a major problem in some Tibetan communities with up to 6% of villagers infected in some villages. In western China, 5-30% of the population are seropositive against E. granulosus antigens, indicating that a large number of individuals have been exposed to the parasite. Although echinococcosis control programs have been initiated in some countries in Central Asia, control efforts are generally fragmented and uncoordinated. Monthly deworming of dogs with praziquantel (PZQ), as a key measure to control the Echinococcus parasites, has been used in western China. However, the approach has proven difficult in local semi-nomadic communities. Additional control measures including health education, domestic livestock animal treatment/vaccination and dog vaccination are needed in CE-endemic areas to accelerate progress.
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Highly sensitive homogenous chemiluminescence immunoassay using gold nanoparticles as label.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 03-12-2014
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Homogeneous immunoassay is becoming more and more attractive for modern medical diagnosis because it is superior to heterogeneous immunoassay in sample and reagent consumption, analysis time, portability and disposability. Herein, a universal platform for homogeneous immunoassay, using human immunoglobulin G (IgG) as a model analyte, has been developed. This assay relies upon the catalytic activity of gold nanoparticles (AuNPs) on luminol-AgNO3 chemiluminescence (CL) reaction. The immunoreaction of antigen and antibody can induce the aggregation of antibody-functionalized AuNPs, and after aggregation the catalytic activity of AuNPs on luminol-AgNO3 CL reaction is greatly enhanced. Without any separation steps, a CL signal is generated upon addition of a trigger solution, and the CL intensity is directly correlated to the quantity of IgG. The detection limit of IgG was estimated to be as low as 3pg/mL, and the sensitivity was better than that of the reported AuNPs-based CL immunoassay for IgG.
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Influence of placement depth on bone remodeling around tapered internal connection implants: a histologic study in dogs.
Clin Oral Implants Res
PUBLISHED: 03-05-2014
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To evaluate the influence of implant-abutment interface (IAI) placement depth on bone remodeling around implants with two different types of tapered internal IAI: screwed-in (SI) and tapped-in (TI) connections in dogs.
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Spectroscopic investigation on sonodynamic and sonocatalytic damage of BSA molecules by Thymol Blue (TB) derivants under ultrasonic irradiation.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-26-2014
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In this paper, the Thymol Blue derivants including Thymol Blue (thymolsulfonphthalein), Thymol Blue-DA (3,3'-Bis [N,N-bis (carboxymethyl) aminomethyl] thymolsulfonphthalein) and Thymol Blue-DA-Fe(III) (3,3'-Bis [N,N-bis (carboxymethyl) aminomethyl] thymolsulfonphthalein-Ferrous(III)) were adopted as sonosensitizers to study the sonodynamic and sonocatalytic activities under ultrasonic irradiation. At first, the interaction of Thymol Blue derivants with bovine serum albumin (BSA) was studied by fluorescence spectroscopy. On that basis, the sonodynamic and sonocatalytic damages of Thymol Blue derivants to BSA under ultrasonic irradiation were investigated by the combination of UV-vis, circular dichroism (CD) and fluorescence spectroscopy. Meanwhile, some influenced factors (ultrasonic irradiation time, Thymol Blue derivants concentration and ionic strength) on the damaging degree of BSA molecules were also reviewed. In addition, synchronous fluorescence spectra were used to estimate the binding and damage sites of Thymol Blue derivants to BSA. Finally, the generation of ROS during sonodynamic and sonocatalytic processes was confirmed by the method of Oxidation-Extraction Spectrometry (OEP). Perhaps, this paper may offer some important subjects for the study of Thymol Blue derivants in sonodynamic therapy (SDT) and sonocatalytic therapy (SCT) technologies for tumor treatment and the effect of the amino acid and central metal.
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Neuropeptide Y acts in the paraventricular nucleus to suppress sympathetic nerve activity and its baroreflex regulation.
J. Physiol. (Lond.)
PUBLISHED: 02-17-2014
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Neuropeptide Y (NPY), a brain neuromodulator that has been strongly implicated in the regulation of energy balance, also acts centrally to inhibit sympathetic nerve activity (SNA); however, the site and mechanism of action are unknown. In chloralose-anaesthetized female rats, nanoinjection of NPY into the paraventricular nucleus of the hypothalamus (PVN) dose-dependently suppressed lumbar SNA (LSNA) and its baroreflex regulation, and these effects were blocked by prior inhibition of NPY Y1 or Y5 receptors. Moreover, PVN injection of Y1 and Y5 receptor antagonists in otherwise untreated rats increased basal and baroreflex control of LSNA, indicating that endogenous NPY tonically inhibits PVN presympathetic neurons. The sympathoexcitation following blockade of PVN NPY inhibition was eliminated by prior PVN nanoinjection of the melanocortin 3/4 receptor inhibitor SHU9119. Moreover, presympathetic neurons, identified immunohistochemically using cholera toxin b neuronal tract tracing from the rostral ventrolateral medulla (RVLM), express NPY Y1 receptor immunoreactivity, and patch-clamp recordings revealed that both NPY and ?-melanocyte-stimulating hormone (?-MSH) inhibit and stimulate, respectively, PVN-RVLM neurons. Collectively, these data suggest that PVN NPY inputs converge with ?-MSH to influence presympathetic neurons. Together these results identify endogenous NPY as a novel and potent inhibitory neuromodulator within the PVN that may contribute to changes in SNA that occur in states associated with altered energy balance, such as obesity and pregnancy.
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Effect of aggregated silver nanoparticles on luminol chemiluminescence system and its analytical application.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-15-2014
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We found that after silver nanoparticles (AgNPs) aggregated, its catalytic activity on luminol CL reaction obviously changed, and the change characteristic was closely related to the sizes of AgNPs. UV-visible spectra, X-ray photoelectron spectra, zeta potential and transmission electron microscopy studies were carried out to investigate the CL effect mechanism. The different CL responses of aggregated AgNPs with different size were suggested to be due to the two effects of quantum size and electron density in nanoparticle's conduction bands, and which one played a major role. The poisonous organic contaminants such as anilines, could induce the aggregation of AgNPs, were observed to affect effectively the luminol-H2O2-7 nm and 15 nm AgNPs CL systems and were detectable by use of a flow injection method with the enhanced or inhibited CL detection.
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Shikonin targets cytosolic thioredoxin reductase to induce ROS-mediated apoptosis in human promyelocytic leukemia HL-60 cells.
Free Radic. Biol. Med.
PUBLISHED: 02-13-2014
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Shikonin, a major active component of the Chinese herbal plant Lithospermum erythrorhizon, has been applied for centuries in traditional Chinese medicine. Although shikonin demonstrates potent anticancer efficacy in numerous types of human cancer cells, the cellular targets of shikonin have not been fully defined. We report here that shikonin may interact with the cytosolic thioredoxin reductase (TrxR1), an important selenocysteine (Sec)-containing antioxidant enzyme with a C-terminal -Gly-Cys-Sec-Gly active site, to induce reactive oxygen species (ROS)-mediated apoptosis in human promyelocytic leukemia HL-60 cells. Shikonin primarily targets the Sec residue in TrxR1 to inhibit its physiological function, but further shifts the enzyme to an NADPH oxidase to generate superoxide anions, which leads to accumulation of ROS and collapse of the intracellular redox balance. Importantly, overexpression of functional TrxR1 attenuates the cytotoxicity of shikonin, whereas knockdown of TrxR1 sensitizes cells to shikonin treatment. Targeting TrxR1 with shikonin thus discloses a previously unrecognized mechanism underlying the biological activity of shikonin and provides an in-depth insight into the action of shikonin in the treatment of cancer.
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Intraperitoneal administration of fetuin-A attenuates D-galactosamine/lipopolysaccharide-induced liver failure in mouse.
Dig. Dis. Sci.
PUBLISHED: 02-10-2014
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Fulminant hepatic failure (FHF) is a devastating syndrome, which sometimes results in death or liver transplantation, in which inflammation would aggravate the development of fetuin-A which would act as an anti-inflammatory factor and may be an available approach to attenuate FHF.
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Mouse Flk-1+Sca-1- mesenchymal stem cells: functional plasticity in vitro and immunoregulation in vivo.
Transplantation
PUBLISHED: 02-04-2014
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Mesenchymal stem cells (MSCs) represent a powerful tool in regenerative medicine because of their differentiation and migration capacities. Moreover, the immunomodulatory ability of MSCs may be used to develop therapies for the treatment of autoimmune diseases.
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Nanoparticle coated paper-based chemiluminescence device for the determination of L-cysteine.
Talanta
PUBLISHED: 01-29-2014
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A laminated paper-based analytical device (LPAD) combined with gold nanoparticles (AuNPs) catalyzed luminol chemiluminescence (CL) system for the determination of L-cysteine (L-cys) was presented here. It is based on the principle that L-cys can greatly inhibit CL signal of AuNPs-luminol-H2O2 system. The paper-based device was fabricated by a low-cost cutting method, followed by lamination with two polyester films. This approach of cutting/lamination to fabricate LPAD is very similar to making a lamination picture. A good linear relationship was obtained between the CL intensity and the concentrations of L-cys in the range from 1.0×10(-8) M to 1.0×10(-6) M with a detection limit at 8.2×10(-10) M (S/N=3). This study shows the successful integration of the LPAD and the CL method. It will be of interest for use in areas such as disease diagnosis in the future.
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Laryngeal schwannoma excised under a microlaryngoscope without tracheotomy: A case report.
Exp Ther Med
PUBLISHED: 01-28-2014
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Schwannomas are benign encapsulated tumors arising from Schwann cells in the peripheral nervous system. Between 25 and 45% of schwannomas occur in the head and neck region. Schwannomas of the larynx are extremely rare with an incidence of 0.1-1.5% in all benign laryngeal tumors. Laryngeal schwannomas usually occur in females aged between their 4th and 5th decades. The most successful curative method is surgical resection. When selecting the surgical method, the size and location of the tumor, as well as the requests of the patient, should be considered. The present case report describes a 29-year-old female patient with symptoms of hoarseness and dyspnea on exertion. Through endoscopic biopsy, histopathology revealed a schwannoma. Considering the symptoms, age and preferences of the patient, the method of trans-oral microlaryngoscopic excision without tracheotomy was used to excise the tumor located in the aryepiglottic fold. Results from a short-term follow-up showed the postoperative result to be satisfactory.
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The use of antibody modified liposomes loaded with AMO-1 to deliver oligonucleotides to ischemic myocardium for arrhythmia therapy.
Biomaterials
PUBLISHED: 01-24-2014
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MicroRNA-1 (miR-1) has been found in cardiac and skeletal tissues. It is overexpressed in ischemic cardiac tissues. Down-regulation of miR-1 could relieve arrhythmogenesis by the anti-miR-1 antisense oligonucleotides (AMO-1). To increase the therapeutic efficiency and inhibit off-target effects of AMO-1, here we explored anti-cardiac troponin I (cTnI) antibody modified liposomes loading with AMO-1 (cT-A-LIP) to deliver the oligonucleotides to ischemic myocardium tissues. Liposomal cytotoxicity was assessed by MTT assay. The targeting abilities to foci were evaluated by in vivo imaging. The uptake and bio-distribution in vitro were observed by live cell station and flow cytometry, respectively. The anti-arrhythmic effects of cT-A-LIP in vivo were evaluated by electrocardiograms (ECG), immunohistochemistry, real-time PCR and patch-clamp recording. Immunohistochemistry showed that cTnI expression had a peak at the third day after myocardial infarction (MI). After cT-LIP administration via tail vein, accumulation of fluorescent trackers in the ischemic foci was significantly increased more than that of LIP. In addition, after cT-A-LIP administration, the ischemic arrhythmias were recovered and ST segment in ECG was elevated nearly back to normal. Compared with MI group, miR-1 expression was significantly down-regulated while Kir2.1 and CX43 protein expression were increased. Patch-clamp recordings showed that cT-A-LIP as well as AMO-1 incubation increased K(+) current density in guinea pigs ventricular cardiomyocytes acting on repolarized membrane potential. In conclusion, the cT-A-LIP not only delivered AMO-1 to ischemic myocardium in MI rats, but validated AMO-1 on relieving ischemic arrhythmia by silencing of miR-1 in ischemic myocardium and restoring the depolarized resting membrane potential (RMP) in MI rats.
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Resveratrol ameliorates diabetic vascular inflammation and macrophage infiltration in db/db mice by inhibiting the NF-?B pathway.
Diab Vasc Dis Res
PUBLISHED: 01-23-2014
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In this study, resveratrol (RSV) - a potent sirtuin 1 activator - was found to have beneficial effects on glucolipid metabolism and improve inflammatory mediators and markers of oxidative stress. Diabetic (db/db) mice and non-diabetic C57BL/6J mice were used in the study. The db/db mice were treated with or without 0.3% RSV mixed with chow for 8 weeks. Dietary RSV significantly lowered blood glucose, plasma lipid and free fatty acid levels in db/db mice. RSV markedly inhibited the expression of intercellular adhesion molecule-1 (ICAM-1), endothelial vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) in the aorta and the blood plasma of db/db mice (p < 0.05). Levels of mac-3-positive macrophages (measure of the infiltration of activated macrophages) were lower in RSV-treated diabetic mice than in their untreated counterparts (p < 0.05). RSV treatment reduced the activity of the transcriptional regulator nuclear factor kappa B (NF-?B) in aortic tissues (p < 0.05). Thus, RSV treatment reduced ICAM-1, VCAM-1 and MCP-1 expression in the aorta and ICAM-1, VCAM-1 and MCP-1 levels in the plasma of diabetic mice. Since dietary supplementation with RSV also reduced NF-?B activities in the aorta, the therapeutic effects of RSV might be associated with the downregulation of NF-?B.
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Enhanced chemiluminescence of CdTe quantum dots-H?O? by horseradish peroxidase-mimicking DNAzyme.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-19-2014
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In this study, it was found that horseradish peroxidase (HRP)-mimicking DNAzyme could effectively enhance the CL emission of CdTe quantum dots (QDs)-H2O2 system, whereas HRP could not enhance the CL intensity. The CL enhancement mechanism was investigated, and the CL enhancement was supposed to originate from the catalysis of HRP-mimicking DNAzyme on the CL reaction between CdTe QDs and H2O2. Meantime, compared with CdTe QDs-H2O2 CL system, H2O2 concentration was markedly decreased in QDs-H2O2-HRP-mimicking DNAzyme CL system, improving the stability of QDs-H2O2 CL system. The QDs-based CL system was used to detect sensitively CdTe QDs and HRP-mimicking DNAzyme (as biologic labels). This work gives a path for enhancing CL efficiency of QDs system, and will be helpful to promote the step of QDs application in various fields such as bioassay and trace detection of analyte.
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Visual chiral recognition of tryptophan enantiomers using unmodified gold nanoparticles as colorimetric probes.
Anal. Chim. Acta
PUBLISHED: 01-15-2014
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A simple protocol to distinguish enantiomers is extremely intriguing and useful. In this study, we propose a low-cost, facile, sensitive method for visual chiral recognition of enantimers. It is based on the inherent chirality of gold nanoparticles (AuNPs), and the unmodified AuNPs are used as chiral selector for D- and L-Tryptophan (Trp). In the presence of D-Trp, an appreciable red-to-blue color change of AuNPs solution can be observed, whereas no color change is found in the presence of L-Trp. The method can be used to detect D-Trp in the range of 0.2-10 ?M, and the limit of detection is 0.1 ?M. The chiral assay described in this work is easily readout with the naked eye or using a UV-vis spectrometer. Furthermore, the AuNPs can selectively adsorb D-Trp, and simple centrifugation can allow the precipitation of D-Trp with AuNPs and leave a net excess of the other enantiomer in solution, thus resulting in enantioseparation. In this method, AuNPs do not need any labeling or modifying with chiral molecules. The method is more attractive because of its high sensitivity, low cost, ready availability and simple manipulation.
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Gambogic acid induces apoptosis in hepatocellular carcinoma SMMC-7721 cells by targeting cytosolic thioredoxin reductase.
Free Radic. Biol. Med.
PUBLISHED: 01-07-2014
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The thioredoxin reductase (TrxR) isoenzymes, TrxR1 in cytosol or nucleus and TrxR2 in mitochondria, are essential mammalian selenocysteine (Sec)-containing flavoenzymes with a unique C-terminal -Gly-Cys-Sec-Gly active site. TrxRs are often overexpressed in a number of human tumors, and the reduction of their expression in malignant cells reverses tumor growth, making the enzymes attractive targets for anticancer drug development. Gambogic acid (GA), a natural product that has been used in traditional Chinese medicine for centuries, demonstrates potent anticancer activity in numerous types of human cancer cells and has entered phase II clinical trials. We discovered that GA may interact with TrxR1 to elicit oxidative stress and eventually induce apoptosis in human hepatocellular carcinoma SMMC-7721 cells. GA primarily targets the Sec residue in the antioxidant enzyme TrxR1 to inhibit its Trx-reduction activity, leading to accumulation of reactive oxygen species and collapse of the intracellular redox balance. Importantly, overexpression of functional TrxR1 in cells attenuates the cytotoxicity of GA, whereas knockdown of TrxR1 sensitizes cells to GA. Targeting of TrxR1 by GA thus discloses a previously unrecognized mechanism underlying the biological action of GA and provides useful information for further development of GA as a potential agent in the treatment of cancer.
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Population-based reference for birth weight for gestational age in northern China.
Early Hum. Dev.
PUBLISHED: 01-06-2014
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Localized birth weight references for gestational age serve as an essential tool in accurate evaluation of atypical birth outcomes (e.g. small for gestational age) in clinical diagnosis and region-specific epidemiological studies. Such standards are currently not available in Mainland China.
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The basic social medical insurance is associated with clinical outcomes in the patients with ST-elevation myocardial infarction: a retrospective study from Shanghai, China.
Int J Med Sci
PUBLISHED: 01-01-2014
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Several social economic factors play important roles in treatments of ST-elevation myocardial infarction (STEMI) and finally influence the clinical outcomes. The basic social medical insurance (BSMI) is an important economic factor in China's medical system. However, the impact of BSMI on clinical outcomes in STEMI patients has not been explored yet. The aim of this study is to investigate whether BSMI is a predictor of clinical outcomes in the patients with STEMI in Shanghai, China.
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The tumor suppressor role of miR-124 in osteosarcoma.
PLoS ONE
PUBLISHED: 01-01-2014
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MicroRNAs have crucial roles in development and progression of human cancers, including osteosarcoma. Recent studies have shown that miR-124 was down-regulated in many cancers; however, the role of miR-124 in osteosarcoma development is unknown. In this study, we demonstrate that expression of miR-124 is significantly downregulated in osteosarcoma tissues and cell lines, compared to the adjacent tissues. The expression of miR-124 in the metastases osteosarcoma tissues was lower than that in non- metastases tissues. We identified and confirmed Rac1 as a novel, direct target of miR-124 using prediction algorithms and luciferase reporter gene assays. Overexpression of miR-124 suppressed Rac1 protein expression and attenuated cell proliferation, migration, and invasion and induced apoptosis in MG-63 and U2OS in vitro. Moreover, overexpression of Rac1 in miR-124-transfected osteosarcoma cells effectively rescued the inhibition of cell invasion caused by miR-124. Therefore, our results demonstrate that miR-124 is a tumor suppressor miRNA and suggest that this miRNA could be a potential target for the treatment of osteosarcoma in future.
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Vinpocetine attenuates neointimal hyperplasia in diabetic rat carotid arteries after balloon injury.
PLoS ONE
PUBLISHED: 01-01-2014
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Diabetes exacerbates abnormal vascular smooth muscle cell (VSMC) accumulation in response to arterial wall injury. Vinpocetine has been shown to improve vascular remolding; however, little is known about the direct effects of vinpocetine on vascular complications mediated by diabetes. The objective of this study was to determine the effects of vinpocetine on hyperglycemia-facilitated neointimal hyperplasia and explore its possible mechanism.
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Bleeding risk and mortality of edoxaban: a pooled meta-analysis of randomized controlled trials.
PLoS ONE
PUBLISHED: 01-01-2014
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Edoxaban, a factor Xa inhibitor, is a new oral anticoagulant that has been developed as an alternative to vitamin K antagonists. However, its safety remains unexplored.
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Effects of obstructive sleep apnea on cardiac function and clinical outcomes in Chinese patients with ST-elevation myocardial infarction.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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The objective of this study was to investigate the influence of OSA on cardiac function in Chinese patients with ST-elevation myocardial infarction (STEMI) and determine the prognostic impact of OSA among these patients.
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G-Quadruplex DNAzyme-Based Chemiluminescence Biosensing Strategy for Ultrasensitive DNA Detection: Combination of Exonuclease III-Assisted Signal Amplification and Carbon Nanotubes-Assisted Background Reducing.
Anal. Chem.
PUBLISHED: 11-18-2013
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Detection of ultralow concentration of specific nucleic acid sequences is important in early diagnosis of gene-related diseases and biodefense application. Herein, we report an amplified chemiluminescence (CL) biosensing platform for ultrasensitive DNA detection. It is based on the exonuclease III-assisted target recycling amplification and catalytic effect of G-quadruplex-hemin DNAzyme to stimulate the generation of CL in the presence of H2O2 and luminol. Moreover, the typical problem of high background induced by excess hemin itself can be effectively addressed through the absorbing of superfluous hemin on the surface of single-walled carbon nanotubes and then removing though centrifugation. Therefore, our proposed biosensing exhibited a high sensitivity toward target DNA with a detection limit of 12 fM, which was about 100-fold lower than that of the DNAzyme-based CL sensor for DNA detection without Exo III-assisted amplification. This sensing platform provides a label-free and cost-effective approach for sensitive detection of DNA.
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OPN Gene Polymorphism and the Serum OPN Levels Confer the Susceptibility and Prognosis of Ischemic Stroke in Chinese Patients.
Cell. Physiol. Biochem.
PUBLISHED: 11-11-2013
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Aim: To investigate the association of Osteopontin (OPN) gene polymorphism and serum thrombin-cleaved OPN level with the susceptibility to ischemic stroke (IS) and its prognosis. Methods: A total of 377 patients with IS and 551 healthy individuals were recruited. The OPN gene polymorphisms at -156 G>GG, -443 C>T and -66 T>G were genotyped. Serum full-length and the thrombin-cleaved OPN were determined. Results: We found that only the -443 C>T polymorphism was significantly associated with the susceptibility to IS. The -443 CC represented a near 2 time higher risk for IS incidence than TT carriers. Also, the -443 CC genotype had significantly poorer outcome and they significantly had higher occurrence for bad recovery as determined by modified Rankin Scale (mRS) (OR=2.18, p=0.043) and Barthel Index (BI) (OR=2.12, p=0.05). The mean serum thrombin-cleaved OPN level in IS group were significantly higher than that in control group. ROC analysis showed that the thrombin-cleaved OPN level (cut-off value, 166.8 ng/ml) can discriminate IS patients from controls with a specificity of 86.3% and a sensitivity of 57.7%. The serum thrombin-cleaved OPN was significantly associated with the clinical outcome at 12 months after discharge from hospital. Conclusion: These results suggest that the -443 C>T polymorphism of OPN gene and serum thrombin-cleaved OPN can be used as a biomarker for the susceptibility and prognosis of IS patients. © 2014 S. Karger AG, Basel.
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Steroid receptor co-activator-3 promotes osteosarcoma progression through up-regulation of FoxM1.
Tumour Biol.
PUBLISHED: 09-20-2013
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Increasing evidence suggests that the three homologous members of steroid receptor co-activator (SRC) family (SRC-1, SRC-2, and SRC-3) play key roles in enhancing cell proliferation in various human cancers, such as breast, prostate, and hepatocellular carcinoma. However, the function of SRC-3 in osteosarcoma remains largely unexplored. In the current study, we found that SRC-3, but not SRC-1 and SRC-2, was dramatically up-regulated in human osteosarcoma tissues, compared with adjacent normal tissues. To explore the functions of SRC-3 in osteosarcoma, in vitro studies were performed in MG63 and U2OS cells. SRC-3 overexpression promoted osteosarcoma cell proliferation, whereas knockdown of SRC-3 inhibits its proliferation. In support of these findings, we further demonstrated that SRC-3 up-regulated FoxM1 expression through co-activation of C/EBP?. Together our results show that SRC-3 drives osteosarcoma progression and imply it as a therapeutic target to abrogate osteosarcoma.
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One-step homogeneous non-stripping chemiluminescence metal immunoassay based on catalytic activity of gold nanoparticles.
Anal. Biochem.
PUBLISHED: 09-16-2013
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The catalytic activity of gold nanoparticles (AuNPs) on a luminol-H2O2 chemiluminescence (CL) system is found to be greatly enhanced after its crosslinking aggregation induced by immunoreaction. Based on this observation, a one-step homogeneous non-stripping CL metalloimmunoassay was designed. In the presence of corresponding antigen (Ag), the immunoreaction caused the aggregation of antibody (Ab)-modified AuNPs, and these crosslinking aggregated AuNPs could catalyze luminol-H2O2 CL reaction to produce a much stronger CL signal than dispersed Ab-modified AuNPs. The assay, including immunoreaction and detection, can be accomplished in homogeneous solution. In the assay, no tedious and strict stripping of metal nanoparticles, difficult synthesis of labels, multiple steps of immunoreactions and washings, and complicated magnetic separation process were required. The detection limit of human immunoglobulin G (IgG, 3?) was estimated to be as low as 3.2×10(-11)gml(-1). The sensitivity was increased by two orders of magnitude over that of other AuNP-based CL immunoassay. The current CL metalloimmunoassay offers the advantages of being simple, cheap, rapid, and sensitive.
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Enhancement in efferocytosis of oxidized low?density lipoprotein-induced apoptotic RAW264.7 cells through Sirt1-mediated autophagy.
Int. J. Mol. Med.
PUBLISHED: 09-08-2013
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Macrophages play a key role in atherosclerotic plaque formation and rupture. These phagocytic cells are important in the scavenging of modified lipoproteins, unwanted or dead cells and cellular debris through efferocytosis. Sirtuin1 (Sirt1), a member of the conserved sirtuin family and a key regulator in the progression of atherosclerosis exerts protective effects by regulating autophagy, a well?known survival mechanism. Inhibition of autophagy may also result in defective efferocytosis. This study aimed to investigate the effect of Sirt1 on the efferocytosis of oxidized low-density lipoprotein (ox-LDL)-induced apoptotic RAW264.7 cells through upregulation of autophagy. The apoptotic cells were incubated with high and low concentrations of Sirt1 activator resveratrol (RSV) and Sirt1 inhibitor nicotinamide (NAM) as well as autophagy inhibitor 3-methyl-adenine (3-MA) + low concentration RSV. Apoptosis was determined by flow cytometry (FCM) of annexin-V/propidium iodide (AV/PI) dual staining. Total proteins were extracted and protein levels were detected through western blot analysis. The ox-LDL uptake and efferocytosis of apoptotic RAW264.7 cells were detected by oil red O staining and calculation of the phagocytic index of apoptotic RAW264.7 cells. The expression of Sirt1 and autophagy marker proteins was simultaneously increased with the stimulation of low concentration RSV (all P<0.05) and decreased in low and high NAM groups (all P<0.05), compared with the control group. Efferocytosis was highest in the low concentration RSV group (P<0.001) and relatively lower in the low and high concentration NAM groups (both P<0.05) compared with the control group, which was similar to the change in the expression of Sirt1 and autophagy marker proteins. The results showed that the efferocytosis of apoptotic RAW264.7 cells was significantly improved with the upregulation of Sirt1?mediated autophagy. Therefore, Sirt1 may serve as a novel therapeutic target for the treatment of atherosclerosis.
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Chemiluminescence resonance energy transfer biosensing platform for site-specific determination of DNA methylation and assay of DNA methyltransferase activity using exonuclease III-assisted target recycling amplification.
Biosens Bioelectron
PUBLISHED: 08-12-2013
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Site-specific determination of DNA methylation and assay of MTase activity can be used for determining specific cancer types, providing insights into the mechanism of gene repression, and developing novel drugs to treat methylation-related diseases. Herein, we develop a simple and highly sensitive chemiluminescence (CL) biosensing platform for site-specific determination of DNA methylation using Exonuclease III (Exo III)-assisted target recycling signal amplification. After bisulfite treatment of mixture of methylated DNA and unmethylated DNA, methylated DNA can hybridize with fluorescein (FAM)-labeled probe DNA to form double-stranded DNA (dsDNA), removing the FAM-labeled probe DNA from the surface of grapheme oxide, and the chemiluminescence resonance energy transfer (CRET) sensing signal can be observed and then amplified using Exo III-based recycling strategy. The biosensing platform exhibits excellent high sensitivity, and it can ever distinguish as low as 0.002% methylation level from the mixture, which is superior to most currently reported methods used for DNA methylation assay. In addition, the proposed method can also be used to sensitively assay MTase activity with determination limit of 0.007U/mL. This CL biosensing offers the advantages of being facile, sensitive, rapid and cost-effective. These features make the system promising for future use for early cancer diagnosis and discover of new anticancer drugs.
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Spectroscopic investigation on interaction and sonodynamic damage of Riboflavin to DNA under ultrasonic irradiation by using Methylene Blue as fluorescent probe.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 07-16-2013
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In this paper, the Riboflavin (RF) as a sonosensitizer and Methylene Blue (MB) as a fluorescent probe were used to study the interaction and sonodynamic damage to Deoxyribonucleic Acid (DNA) by fluorescence and UV-vis spectroscopy. The results showed that the RF could efficiently bind to DNA in aqueous solution and exchange with the MB through competing reaction. And then, under ultrasonic irradiation, the RF could obviously damage the DNA. In addition, the influencing factors such as ultrasonic irradiation time and RF concentration on the sonodynamic damage to DNA were also considered. The experimental results showed that the sonodynamic damage degree increase with the increase of ultrasonic irradiation time and RF concentration. Perhaps, this paper may offer some important subjects for broadening the application of RF in sonodynamic therapy (SDT) technologies for tumor treatment.
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Automated analysis of diabetic retinopathy images: principles, recent developments, and emerging trends.
Curr. Diab. Rep.
PUBLISHED: 05-21-2013
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Diabetic retinopathy (DR) is a vision-threatening complication of diabetes. Timely diagnosis and intervention are essential for treatment that reduces the risk of vision loss. A good color retinal (fundus) photograph can be used as a surrogate for face-to-face evaluation of DR. The use of computers to assist or fully automate DR evaluation from retinal images has been studied for many years. Early work showed promising results for algorithms in detecting and classifying DR pathology. Newer techniques include those that adapt machine learning technology to DR image analysis. Challenges remain, however, that must be overcome before fully automatic DR detection and analysis systems become practical clinical tools.
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Paper-based chromatographic chemiluminescence chip for the detection of dichlorvos in vegetables.
Biosens Bioelectron
PUBLISHED: 05-13-2013
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Paper chromatography was a big breakthrough in the early of 20th century but it is rarely used due to the long separation time and the diffusion on the sample spots. In this work, for the first time, a paper-based chemiluminescence (CL) analytical device combined with paper chromatography was developed for the determination of dichlorvos (DDV) in vegetables without complicated sample pretreatment. The paper chromatography separation procedure can be accomplished in 12 min on a paper support (0.8 × 7.0 cm(2)) by using 5 µL sample spotted on it. After sample developing, the detection area (0.8 × 1.0 cm(2)) was cut and inserted between two layers of water-impermeable single-sided adhesive tapes. The paper-based chip was made by attaching the middle layer of paper onto the bottom layer. Then it was covered by another tape layer, which was patterned by the cutting method to form a square hole (0.8 × 1.0 cm(2)) in it. 10 ?L mixed solution of luminol and H2O2 was dropped on the detection area to produce CL. A linear relationship was obtained between the CL intensity and the concentrations of DDV in the range between 10.0 ng mL(-1) and 1.0 ?g mL(-1)and the detection limit was 3.6 ng mL(-1). Water-soluble metal ions and vitamins can be developed at different spatial locations relative to DDV, eliminating interference with DDV during detection. The paper-based chromatographic chip can be successfully used for the determination of DDV without complicated sample preparation in vegetables. This study should, therefore, be suitable for rapid and sensitive detection of trace levels of organophosphate pesticides in environmental and food samples.
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The complete mitochondrial genome of Liriomyza huidobrensis and comparison with L. trifolii and L. sativae (Diptera: Agromyzidae).
Mitochondrial DNA
PUBLISHED: 04-25-2013
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Abstract Liriomyza huidobrensis, L. trifolii and L. sativae (Diptera: Agromyzidae) are serious horticultural pests. The three species are very similar and difficult to discriminate from each other. In this study, we report the mitochondrial genome of L. huidobrensis and compare with L. trifolii and L. sativae. The mitochondrial genome of L. huidobrensis is 16,239?bp long, and it contains 37 genes and one A?+?T-rich region as do the sequenced liriomyza species. The sequence and structure of H51-H100 region in srRNA is significantly different from that of L. trifolii and L. sativae. The greatest sequence differences among the three leafminers are located in the region including ND2, ND3, ND6, ATP6, ATP8, CYTb and A+T region, which can be considered as candidate regions for molecular identification or SNP markers.
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Anionic polythiophene derivative as peroxidase mimetics and their application for detection of hydrogen peroxide and glucose.
Talanta
PUBLISHED: 04-19-2013
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In this paper, we discovered that the anionic polythiophenes derivative, poly[2-(3-thienyl)ethyloxy-4-butylsulfonate] (PTEBS), possesses intrinsic peroxidase-like activity that can catalyze the reaction of peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) in the presence of H2O2 to produce a blue color reaction, which provides colorimetric detection of H2O2. PTEBS exhibits several advantages such as high catalytic efficiency, good stability, and rapid response over horseradish peroxidase (HRP). By coupling the oxidation of glucose catalyzed by glucose oxidase, a simple, inexpensive, highly sensitive and selective colorimetric method for glucose detection has been developed. The absorbance was proportional to the concentration of glucose in the range from 0.01 to 0.5mM with a detection limit of 0.004 mM. This work is not only of importance for a better understanding of the unique properties of polythiophenes derivative but also of great potential for medical diagnostics and biotechnology.
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Visual detection of hexokinase activity and inhibition with positively charged gold nanoparticles as colorimetric probes.
Analyst
PUBLISHED: 04-19-2013
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Positively charged gold nanoparticles can effectively differentiate ATP and ADP, thus providing a simple and visual approach to colorimetric detection of hexokinase activity and inhibition.
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Leptin and its receptor expression in dental and periodontal tissues of primates.
Cell Tissue Res.
PUBLISHED: 03-30-2013
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Leptin and its receptor (OBR) have attracted much attention since their discovery. They have been reported to play central roles in energy balance, the immune-inflammatory response and bone metabolism. Evidence indicates that leptin and OBR are associated with inflammatory diseases of dental and periodontal tissues. The first step for establishing this is to determine the expression of leptin and OBR in these tissues. Our study is the first to examine systematically the expression of leptin and OBR in dental and periodontal tissues of monkeys (Macaca fascicularis) by immunohistochemistry and in primary cultured cells, isolated from human dental and periodontal tissues, by reverse transcription plus the polymerase chain reaction and immunocytochemistry. Our results show that leptin and OBR are constitutively expressed and widely distributed in dental and periodontal tissues of primates. Their immunoreaction is especially strong in junctional epithelium, a unique front-line defense around teeth and in mineralizing areas of the dental pulp and periodontal ligament. The expression of the long and also functional form of OBR (OBRb) indicates that leptin has a direct effect on these cells. Thus, we can reasonably infer that leptin and OBR exert effects on defense, mineralization and angiogenesis in dental and periodontal tissues of primates.
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Spectroscopic studies on H2O2 damaging BSA induced by 1,2-dihydroxy-9, 10-anthraquinone-3-aminomethyl-N, N-diacetate-ferrous(III).
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 03-29-2013
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The interaction between 1,2-dihydroxy-9, 10-anthraquinone-3-aminomethyl-N, N-diacetate-Ferrous(III) (Alizarin-DA-Fe(III)) and bovine serum albumin (BSA) was studied by using UV-vis and fluorescence spectra. And then, the H2O2 damage of BSA induced by Alizarin-DA-Fe(III) was examined. The results show that due to the interaction the fluorescence of BSA solution can be obviously quenched by Alizarin-DA-Fe(III) and that the quenching process belongs to the static quenching. In addition, in the presence of Alizarin-DA-Fe(III) the BSA molecules were markedly damaged by H2O2. Meanwhile, the effects of the standing time, Alizarin-DA-Fe(III) concentration and H2O2 concentration on the damage of BSA molecules were also researched. The experimental results demonstrate that the damage degree increase with the increase of standing time, Alizarin-DA-Fe(III) concentration and H2O2 concentration. Finally, the generation of reactive oxygen species (ROS) from H2O2 induced by Alizarin-DA-Fe(III) as Fenton-like reagent was estimated by some quenchers. Because the Iminodiacetic-Ferrous(III) (IDA-Fe(III)) and Nitrilotriacetic-Ferrous(III) (NTA-Fe(III)) can be thought of as the active part of Alizarin-DA-Fe(III), they were used to compare the catalytic activity with Alizarin-DA-Fe(III). Owing to the special plane structure, the experiment results showed that the Alizarin-DA-Fe(III) exhibited higher damage ability than IDA-Fe(III) and NTA-Fe(III). Perhaps, the Alizarin-DA-Fe(III) may be used as a new antitumor compound to induce peroxides in body to kill cancer cells.
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Improvement of sonocatalytic activity of TiO2 by using Yb, N and F-doped Er3+:Y3Al5O12 for degradation of organic dyes.
Ultrason Sonochem
PUBLISHED: 03-16-2013
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In this study, several up-conversion luminescence agents (Er(3+):Y3Al5O12, Er(3+):Yb0.2Y2.79Al5O12, Er(3+):Yb0.2Y2.79Al5N0.01O11.99, Er(3+):Yb0.2Y2.79Al5F0.01O11.99 and Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98) were synthesized using sol-gel method. And then, the corresponding sonocatalyst (Er(3+):Y3Al5O12/TiO2, Er(3+):Yb0.2Y2.79Al5O12/TiO2, Er(3+):Yb0.2Y2.79Al5N0.01O11.99/TiO2, Er(3+):Yb0.2Y2.79Al5F0.01O11.99/TiO2 and Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98/TiO2 coated composites) were prepared by sol-gel coating process. The synthesized up-conversion luminescence agents and their coated composites were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). And that, the sonocatalytic activities were detected through the degradation of Azo Fuchsine (AF) dye in aqueous solution by UV-vis spectroscopy. Some key influences such as heat-treated temperature and heat-treated time on the sonocatalytic activity of Er(3+):YbaY2.99-aNxFyAl5O12-x-y/TiO2 coated composite, as well as ultrasonic irradiation time and initial dye concentration on the sonocatalytic degradation were studied. The results showed that the doping of Yb, N and F into Er(3+):Y3Al5O12/TiO2 significantly enhanced the sonocatalytic activity of Er(3+):Y3Al5O12/TiO2 coated composite in the degradation of organic dyes. Particularly, Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98/TiO2 coated composites with 3:7 M ratio heat-treated at 550 °C for 60 min showed the highest sonocatalytic activity. At last, the experiments also indicated that the Er(3+):Yb0.2Y2.79Al5N0.01F0.01O11.98/TiO2 coated composites has a good sonocatalytic activity to degrade other organic dyes under ultrasonic irradiation.
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The protective effect of fasudil on the structure and function of cardiac mitochondria from rats with type 2 diabetes induced by streptozotocin with a high-fat diet is mediated by the attenuation of oxidative stress.
Biomed Res Int
PUBLISHED: 02-19-2013
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Dysfunction of cardiac mitochondria appears to play a substantial role in cardiomyopathy or myocardial dysfunction and is a promising therapeutic target for many cardiovascular diseases. We investigated the effect of the Rho/Rho-associated protein kinase (ROCK) inhibitor fasudil on cardiac mitochondria from rats in which diabetes was induced by a combination of streptozotocin (STZ) and a sustained high-fat diet. Eight weeks after diabetes was induced by a single intraperitoneal injection of 50 mg/kg STZ followed by a sustained high-fat diet, either fasudil (5 mg/kg bid) or equivalent volumes of saline (control) were administered over four weeks. Fasudil significantly protected against the histopathologic changes of cardiac mitochondria in diabetic rats. Fasudil significantly reduced the abundances of the Rho A, ROCK 1, and ROCK 2 proteins, restored the activities of succinate dehydrogenase (SDH) and monoamine oxidase (MAO) in cardiac mitochondria, inhibited the opening of the mitochondrial permeability transition pore, and decreased the total antioxidant capacity, as well as levels of malonyldialdehyde, hydroxy radical, reduced glutathione, and superoxide dismutase in heart. Fasudil improved the structures of cardiac mitochondria and increased both SDH and MAO activities in cardiac mitochondria. These beneficial effects may be associated with the attenuation of oxidative stress caused by fasudil treatment.
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Leptin acts in the forebrain to differentially influence baroreflex control of lumbar, renal, and splanchnic sympathetic nerve activity and heart rate.
Hypertension
PUBLISHED: 02-19-2013
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Although leptin is known to increase sympathetic nerve activity (SNA), we tested the hypothesis that leptin also enhances baroreflex control of SNA and heart rate (HR). Using ?-chloralose anesthetized male rats, mean arterial pressure (MAP), HR, lumbar SNA (LSNA), splanchnic SNA (SSNA), and renal SNA (RSNA) were recorded before and for 2 hours after lateral cerebroventricular leptin or artificial cerebrospinal fluid administration. Baroreflex function was assessed using a 4-parameter sigmoidal fit of HR and SNA responses to slow ramp (3-5 minutes) changes in MAP, induced by intravenous infusion of nitroprusside and phenylephrine. Leptin (3 ?g) increased (P<0.05) basal LSNA, SSNA, RSNA, HR, and MAP, and the LSNA, SSNA, RSNA, and HR baroreflex maxima. Leptin also increased gain of baroreflex control of LSNA and RSNA, but not of SSNA or HR. The elevations in HR were eliminated by pretreatment with methscopalamine, to block parasympathetic nerve activity; however, after cardiac sympathetic blockade with atenolol, leptin still increased basal HR and MAP and the HR baroreflex maximum and minimum. Leptin (1.5 ?g) also increased LSNA and enhanced LSNA baroreflex gain and maximum, but did not alter MAP, HR, or the HR baroreflex. Lateral cerebroventricular artificial cerebrospinal fluid had no effects. Finally, to test whether leptin acts in the brain stem, leptin (3 ?g) was infused into the 4th ventricle; however, no significant changes were observed. In conclusion, leptin acts in the forebrain to differentially influence baroreflex control of LSNA, RSNA, SSNA, and HR, with the latter action mediated via suppression of parasympathetic nerve activity.
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Enhanced effect of aggregated gold nanoparticles on luminol chemiluminescence system and its analytical application.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-14-2013
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Some organic compounds containing groups of OH, NH2, or SH, which could induce the aggregation of gold nanoparticles (AuNPs), were observed to enhance effectively the luminol-H2O2-2.6 nm AuNPs CL system. It was found that the aggregation of AuNPs was an important effect factor for the catalytic activity of AuNPs on luminol CL system. The aggregated AuNPs could effectively enhance luminol CL signal compared with the dispersed one. The enhanced effect was closely related to the sizes of AuNPs. Among the studied AuNPs with seven sizes, 2.6 nm AuNPs had the greatest enhancement effect on luminol CL system after its aggregation. The CL enhancement mechanism was investigated, and the marked enhancement of aggregated 2.6 nm AuNPs for luminol CL system was supposed to originate from the decrease of AuNPs surface negative charge density compared to its dispersed state. For the luminol-H2O2-2.6 nm AuNPs CL system in the presence of organic compounds containing groups of OH, NH2, or SH, more than one factor played the role in influencing the CL intensity. It was found that the enhanced effect of aggregated 2.6 nm AuNPs induced by such organic compounds was much more significant than the inhibition effect of reducing groups of OH, NH2, or SH, which made it applicable for the determination of this kind of compounds.
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Metal artifacts reduction using monochromatic images from spectral CT: evaluation of pedicle screws in patients with scoliosis.
Eur J Radiol
PUBLISHED: 02-14-2013
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To evaluate the effectiveness of spectral CT in reducing metal artifacts caused by pedicle screws in patients with scoliosis.
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Learning skill-defining latent space in video-based analysis of surgical expertise - a multi-stream fusion approach.
Stud Health Technol Inform
PUBLISHED: 02-13-2013
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In recent years, surgical simulation has emerged at the forefront of new technologies for improving the education and training of surgical residents. To objectively evaluate the surgical skills of the trainees and reduce the training cost, an automated method for rating the performance of the operator is critical. However, automated evaluation of surgical skills in a video-based system, e.g., the FLS trainer box, is still a challenging task, both due to the lack of reliable visual features and the lack of analysis tools that bridge the semantic gap between the low-level visual features and the high-level surgical skills. This study attempts to find a latent space for the visual features for supporting more meaningful analysis of surgical skills. The approach employs multi-modality fusion and Canonical Correlation Analysis as the key techniques. Experiments were designed to evaluate the proposed approach. The results suggest that this is a promising direction.
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Conjugated polyelectrolytes-initiated chemiluminescence: a biosensing platform for label-free and homogeneous DNA detection.
Biosens Bioelectron
PUBLISHED: 01-22-2013
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In this study, it was found that conjugated polyelectrolytes (CPEs) would initiate the strong chemiluminescence (CL) emission of luminol-H2O2 in weak basic media. Using CL spectra, ultraviolet visible light spectra, fluorescence spectra and electron spin resonance (ESR) spectra, the catalytic mechanism of CPEs on luminol-H2O2 CL was discussed in detail. Furthermore, it was found that the catalytic activity of poly [3-(3-N,N,N-triethylamino-1-propyloxy)-4-methyl-2,5-thiophene hydro chloride] (PMNT) (a kind of cationic CPEs) on the luminol-H2O2 CL system was closely relevant to the conformation of PMNT. The CL intensity of luminol-H2O2-PMNT system in the presence of single-stranded DNA was much larger than that in the presence of double-stranded DNA. By taking advantage of this phenomenon, a label-free and homogeneous CL detection of DNA hybridization is proposed. The detection limit of target DNA (3?) was estimated to be as low as 3.7×10(-13)M. The present CL method for DNA hybridization detection offers the advantages of being simple, cheap, rapid and sensitive.
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Impaired PI3 K Akt expression in liver and skeletal muscle of ovariectomized rats.
Endocrine
PUBLISHED: 01-22-2013
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It is well established that estrogen deficiency is strongly linked to the development of insulin resistance (IR), but the mechanism is still unclear. Since IR is characterized by a marked reduction in insulin-stimulated PI3 K-mediated activation of Akt in liver and skeletal muscle, we hypothesized that ovariectomized rats (OVX) would exhibit reductions in the expression of proteins in PI3 K signaling pathway, including PI3 K and Akt. As hypothesized, after observing for 12 weeks, compared with the SHAM rats, ovariectomy led to decreased plasma estrogen level and increased HOMA-IR index; in addition, ovariectomy also caused decreased PI3 K and Akt expression levels in the liver and skeletal muscle. Interestingly, the expression patterns differed in tissue-dependent fashion: Akt1 was only found reduction in liver, whereas Akt2 decreased in muscle; these changes can be reversed by estrogen supplement (OVXE). In conclusion, data demonstrate that estrogen withdrawals may cause IR at least in part by impaired PI3 K/Akt signaling proteins in liver and skeletal muscle, and Akt1 and Akt2 might be tissue-specific expressions.
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The genome of the hydatid tapeworm Echinococcus granulosus.
Nat. Genet.
PUBLISHED: 01-14-2013
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Cystic echinococcosis (hydatid disease), caused by the tapeworm E. granulosus, is responsible for considerable human morbidity and mortality. This cosmopolitan disease is difficult to diagnose, treat and control. We present a draft genomic sequence for the worm comprising 151.6 Mb encoding 11,325 genes. Comparisons with the genome sequences from other taxa show that E. granulosus has acquired a spectrum of genes, including the EgAgB family, whose products are secreted by the parasite to interact and redirect host immune responses. We also find that genes in bile salt pathways may control the bidirectional development of E. granulosus, and sequence differences in the calcium channel subunit EgCav?1 may be associated with praziquantel sensitivity. Our study offers insights into host interaction, nutrient acquisition, strobilization, reproduction, immune evasion and maturation in the parasite and provides a platform to facilitate the development of new, effective treatments and interventions for echinococcosis control.
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Magnetic field assisted photocatalytic degradation of organic dyes in the presence of Ag/TiO(2) coated composite.
Water Sci. Technol.
PUBLISHED: 01-12-2013
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Ag/TiO(2) coated composite was prepared via sol-gel method in order to elucidate its application in magnetic field assisted photocatalytic degradation of dyes. Through the degradation of organic dyes, the key influences such as Ag amount, heat-treated temperature and time on the photocatalytic activity of Ag/TiO(2), as well as UV irradiation time, rotational speed, dye concentration and magnetic sheet number on the photocatalytic degradation were studied. Results showed that the Ag/TiO(2) with 25 wt% Ag content heat-treated at 550 °C for 60 min has the best photocatalytic activity. With the increase of UV light irradiation time, rotational speed and magnetic sheet number, the degradation rate is improved. Different dye degradation proved that the method could universally be used.
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[Purification and identification of HMGB1 secreted by liver cells and immune cells].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 12-16-2011
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To purify and identify HMGB1 secreted by liver cells HepG2 and immune cells U937.
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3,4,4-Trihydroxy-trans-stilbene, an analogue of resveratrol, is a potent antioxidant and cytotoxic agent.
Free Radic. Res.
PUBLISHED: 10-25-2011
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Resveratrol (3,5,4-trihydroxy-trans-stilbene) is a naturally occurring polyphenol widely distributed in food and dietary plants. This phytochemical has been intensively studied as an efficient antioxidant and anticancer agent, and a variety of substituted stilbenes have been developed in order to improve the potency of resveratrol. In this work, we described the synthesis of 3,4,4 -trihydroxy-trans-stilbene (3,4,4-THS), an analogue of resveratrol, and studied its antioxidant and cytotoxic activity in vitro. 3,4,4 -THS was much more efficient than resveratrol in protecting against free radical-induced lipid peroxidation, photo-sensitized DNA oxidative damage, and free radical-induced hemolysis of human red blood cells. More potent growth inhibition in cultured human leukemia cells (HL-60) was also observed for 3,4,4 -THS. The relationship between the antioxidant efficiency and cytotoxic activity was discussed, with the emphasis on inhibition of the free radical enzyme ribonucleotide reductase by antioxidants. The result that this subtle structure modification of resveratrol drastically improves its bioactivity provides important strategy to develop novel resveratrol-based molecules.
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Solid lipid nanoparticle suspension enhanced the therapeutic efficacy of praziquantel against tapeworm.
Int J Nanomedicine
PUBLISHED: 10-18-2011
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Hydatid disease caused by tapeworm is an increasing public health and socioeconomic concern. In order to enhance the therapeutic efficacy of praziquantel (PZQ) against tapeworm, PZQ-loaded hydrogenated castor oil solid lipid nanoparticle (PZQ-HCO-SLN) suspension was prepared by a hot homogenization and ultrasonication method. The stability of the suspension at 4°C and room temperature was evaluated by the physicochemical characteristics of the nanoparticles and in-vitro release pattern of the suspension. Pharmacokinetics was studied after subcutaneous administration of the suspension in dogs. The therapeutic effect of the novel formulation was evaluated in dogs naturally infected with Echinococcus granulosus. The results showed that the drug recovery of the suspension was 97.59% ± 7.56%. Nanoparticle diameter, polydispersivity index, and zeta potential were 263.00 ± 11.15 nm, 0.34 ± 0.06, and -11.57 ± 1.12 mV, respectively and showed no significant changes after 4 months of storage at both 4°C and room temperature. The stored suspensions displayed similar in-vitro release patterns as that of the newly prepared one. SLNs increased the bioavailability of PZQ 5.67-fold and extended the mean residence time of the drug from 56.71 to 280.38 hours. Single subcutaneous administration of PZQ-HCO-SLN suspension obtained enhanced therapeutic efficacy against tapeworm in infected dogs. At the dose of 5 mg/kg, the stool-ova reduction and negative conversion rates and tapeworm removal rate of the suspension were 100%, while the native PZQ were 91.55%, 87.5%, and 66.7%. When the dose reduced to 0.5 mg/kg, the native drug showed no effect, but the suspension still got the same therapeutic efficacy as that of the 5 mg/kg native PZQ. These results demonstrate that the PZQ-HCO-SLN suspension is a promising formulation to enhance the therapeutic efficacy of PZQ.
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Naked-eye sensitive detection of nuclease activity using positively-charged gold nanoparticles as colorimetric probes.
Chem. Commun. (Camb.)
PUBLISHED: 10-17-2011
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Positively-charged gold nanoparticles can effectively differentiate long DNA and fragmented DNA, thus providing a simple and visual approach to colorimetric detection of nuclease activity.
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PAX6 analysis of one family and one sporadic patient from southern China with classic aniridia.
Mol. Vis.
PUBLISHED: 10-03-2011
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To investigate the paired box gene 6 (PAX6) in three patients from southern China presenting with classic aniridia: two patients from two successive generations of one family and one sporadic patient.
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Label-free fluorescence method for screening G-quadruplex ligands.
Anal. Biochem.
PUBLISHED: 07-29-2011
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G-quadruplex ligands can interfere with the telomere structure, telomere elongation/replication, and proliferation of cancer cells. A key element in the development of potent G-quadruplex ligands is the screening of large chemical libraries of potential candidates. Here, we describe a simple fluorescence method for screening of G-quadruplex ligands. The method is based on the ability of G-quadruplex ligands to displace hemin from G-quadruplex-based DNAzyme, resulting in a decrease of its catalytic activity on the fluorescence-developing reaction between p-hydroxyphenylacetic acid and H(2)O(2). The method eliminates the requirement for expensive and time-consuming preparation of labeled DNA. Our method provides a simple, cheap, and sensitive approach to screen G-quadruplex ligands (potential antitumor drugs).
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Small molecule inhibitors of mammalian thioredoxin reductase.
Free Radic. Biol. Med.
PUBLISHED: 07-15-2011
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Mammalian thioredoxin reductases (TrxRs) are a family of NADPH-dependent flavoproteins with a penultimate selenocysteine residue at the carboxy-terminus. Besides their native substrate thioredoxins (Trx), the enzymes show a broad substrate specificity, at least partially, because of the C-terminal redox-active site that is easily accessible in the reduced form. TrxRs are ubiquitous in all kinds of cells and have a critical role in regulating intracellular redox signaling. In recent years, a wealth of evidence has revealed that overactivation/dysfunction of TrxRs is closely related to various diseases, especially in tumor development, and thus the past decades have witnessed an expanding interest in finding TrxRs inhibitors, which might be promising agents for cancer chemotherapy. Herein we reviewed the small molecule inhibitors of mammalian TrxRs, with an emphasis on those that have potential anticancer activity. This review includes the nonpatent references up to 2010 that deal with mammalian TrxR inhibitors.
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Label-free fluorescent detection of thrombin using G-quadruplex-based DNAzyme as sensing platform.
Analyst
PUBLISHED: 07-04-2011
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We report herein a label-free and sensitive fluorescent method for detection of thrombin using a G-quadruplex-based DNAzyme as the sensing platform. The thrombin-binding aptamer (TBA) is able to bind hemin to form the G-quadruplex-based DNAzyme, and thrombin can significantly enhance the activity of the G-quadruplex-based DNAzyme. The G-quadruplex-based DNAzyme is found to effectively catalyze the H(2)O(2)-mediated oxidation of thiamine, giving rise to fluorescence emission. This allows us to utilize the H(2)O(2)-thiamine fluorescent system for the quantitative analysis of thrombin. The assay shows a linear toward thrombin concentration in the range of 0.01-0.12 nM. The present limit of detection for thrombin is 1 pM, and the sensitivity for analyzing thrombin is improved by about 10,000-fold as compared with the reported colorimetric counterpart. The work also demonstrates that thiamine is an excellent substrate for the fluorescence assay using the G-quadruplex-based DNAzyme as the sensing platform.
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[Determination of mangiferin in rat plasma and aqueous humor by HPLC].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 06-11-2011
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A HPLC method was developed for the determination of mangiferin in rat plasma and aqueous humor. 4-Nitrophenol was used as internal standard. Analysis was performed on a Cosmosil ODS C18 analytical column (4.6 mm x 250 mm, 5 microm) with mobile phase consisting of methanol-water (40: 60) with 2% glacial acetic acid at a flow rate of 1.0 mL x min(-1). The calibration curve of mangiferin in rat plasma and aqueous humor showed excellent linear behaviors over the investigated concentration of 0. 50-250.00 mg x L(-1) in plasma and 0.10-10.00 mg x L(-1) in aqueous humor, respectively, and the correlation coefficients were all above 0.995 4. The intra-day and inter-day precisions for all samples were measured to be below 12%. The limit of quantitation was 0.10 mg x L(-1) and low enough for the determination of mangiferin in all samples. The validated method has been successfully applied to preliminary pharmacokinetics study of mangiferin in rat plasma and aqueous humor.
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Human papillomavirus type 16 variant analysis of E6, E7, and L1 [corrected] genes and long control region in [corrected] cervical carcinomas in patients in northeast China.
J. Clin. Microbiol.
PUBLISHED: 05-18-2011
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Human papillomavirus type 16 (HPV 16) plays a cardinal role in the pathogenesis of cervical cancer. HPV 16 has intratypic variants which show different geographical distributions and different oncogenic potentials. To analyze the presence of sequence variations of HPV 16 variants in northeast China, 71 cervical carcinomas were identified by HPV typing. HPV 16-positive specimens were analyzed by PCR-directed sequencing in the E6, E7, and L1 genes and the LCR (long control region). The variation data were compared with those of neighboring districts. In this hospital-based study, HPV 16 was the most common type (73.24%). In HPV 16-positive specimens, 67.31% belonged to the European (E) lineage, while 32.69% were Asian (As) variants. The Asian-American (AA), African-1 (Af-1), African-2 (Af-2), and northern American (NA) lineages were not detected. The most frequently observed variation sites were T178G (32.69%) in E6; A647G (34.62%), G666A (38.46%), and T846C (32.69%) in E7; C6826T (36.17%) and G7060A (61.70%) in L1; and G7521A (98.08%) in the LCR. The most prevalent amino acid variations were D25E in E6 and N29S in E7. In addition, 28 novel variations of HPV 16 were reported. Some covariations between different genes were obtained. In this study, HPV 16 variants belonged to the European lineage and the Asian lineage. Compared with neighboring districts, the distribution of HPV 16 variants in northeast China had a typical pattern. As the first report on HPV 16 variants in northeast China, it should be helpful for designing a HPV vaccine and HPV vaccination program in China.
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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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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.