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Find video protocols related to scientific articles indexed in Pubmed.
[Experimental study on closed plasma discharging under low pressure and spectroscopic diagnosis].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 11-01-2014
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Closed plasma can overcome difficulties of maintaining plasma and excessive energy consumption in open environment. For plasma stealth technology, a closed plasma generator was designed. Using microsecond pulse generator and argon as working gas, discharge experiments were carried out under low pressure environment. The emission spectrum of Ar at different position in discharge chamber was measured. By using collisional-radiative modal (CRM), the distribution of plasma parameters was studied. At a given electron temperature and density with specified discharge parameters, corresponding population distribution could be obtained by CRM. By comparing the line ratio of argon 2p levels acquired from CRM with the line ratio from spectrum measured, the plasma parameters were confirmed after obtaining the minimum difference value. Using the line ratio of argon 2p9 to 2p1 from CRM while the range of electron density was 1-5 eV, the calculating error was analyzed. The results reveal that, the electron density of the closed plasma reaches a magnitude of 10(11) cm(-3) and shows a gradient distribution with small variational amplitude, and the distribution is beneficial to the application of plasma stealth.
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Silver(i)-catalyzed annulation for the regioselective synthesis of N-imino-?-carbolinium ylides from hydrazones of indole-3-carbonyl derivatives and propargylic alcohols.
Org. Biomol. Chem.
PUBLISHED: 10-28-2014
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A regioselective efficient synthetic approach to N-imino-?-carbolinium ylides via AgOTf-catalyzed iminoannulation has been developed. This transformation proceeds via a silver(i) triflate-catalyzed consecutive Friedel-Crafts reaction/N-C bond formation sequence between the readily available indole derivatives and propargylic alcohols.
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High prevalence of pfmdr1 N86Y and Y184F mutations in Plasmodium falciparum isolates from Bioko island, Equatorial Guinea.
Pathog Glob Health
PUBLISHED: 10-27-2014
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Objective: Drug resistance against Plasmodium falciparum has been recognized as the crucial obstacle to curbing mortality and morbidity from malaria. To investigate the distribution and pattern of multidrug resistance 1 (pfmdr1) gene polymorphisms in P. falciparum, isolates collected from the malaria high-endemic Bioko Island, Equatorial Guinea. Methods: Blood samples were collected from 217 patients with P. falciparum malaria during rainy season in 2012 on Bioko Island. These samples were extracted using Chelex to obtain parasite DNA. Nest-polymerase chain reaction (PCR) and sequencing were employed to detect mutations (N86Y, E130K, Y184F, S1034C, N1042D, V1109I, and D1246Y) and haplotypes in pfmdr1 gene. Results: A total of 151 samples were successfully detected for pfmdr1 mutations from the 217 patients. Pfmdr1 mutations were found in 91·39% (138/151) P. falciparum isolates. However, no mutation at 130 and 1109 was identified from these samples. Four haplotypes coding 86, 184, 1034, 1?042, and 1?246 were found including NYSND, YYSND, NFSND, and YFSND, which accounted for 8·61% (13/151), 2·65% (4/151), 29·80% (45/151), and 58·94% (89/151), respectively. Conclusions: Our results exhibited hypersensitivity to lumefantrine (LU) and mefloquine (MQ) and resistance to chloroquine (CQ) and amodiaquine (AQ) in P. falciparum isolates from Bioko Island. This information will be useful for anti-malarial drug policy in Equatorial Guinea.
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Identification of human prolactinoma related genes by DNA microarray.
J Cancer Res Ther
PUBLISHED: 10-15-2014
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To identify the genes involved in prolactinoma by bioinformatics methods and provide new potential biomarkers for prolactinoma.
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Hydrazine-mediated construction of nanocrystal self-assembly materials.
ACS Nano
PUBLISHED: 10-13-2014
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Self-assembly is the basic feature of supramolecular chemistry, which permits to integrate and enhance the functionalities of nano-objects. However, the conversion of self-assembled structures to practical materials is still laborious. In this work, on the basis of studying one-pot synthesis, spontaneous assembly, and in situ polymerization of aqueous semiconductor nanocrystals (NCs), NC self-assembly materials are produced and applied to design high performance white light-emitting diode (WLED). In producing self-assembly materials, the additive hydrazine (N2H4) is curial, which acts as the promoter to achieve room-temperature synthesis of aqueous NCs by favoring a reaction-controlled growth, as the polyelectrolyte to weaken inter-NC electrostatic repulsion and therewith facilitate the one-dimensional self-assembly, and in particular as the bifunctional monomers to polymerize with mercapto carboxylic acid-modified NCs via in situ amidation reaction. This strategy is versatile for mercapto carboxylic acid-modified aqueous NCs, for example CdS, CdSe, CdTe, CdSexTe1-x, and CdyHg1-yTe. Because of the multisite modification with carboxyl, the NCs act as macromonomers, thus producing cross-linked self-assembly materials with excellent thermal, solvent, and photostability. The assembled NCs preserve strong luminescence and avoid unpredictable fluorescent resonance energy transfer, the main problem in design WLED from multiple NC components. These advantages allow the fabrication of NC-based WLED with high color rendering index (86), high luminous efficacy (41 lm/W), and controllable color temperature.
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The genome of Paenibacillus sabinae T27 provides insight into evolution, organization and functional elucidation of nif and nif-like genes.
BMC Genomics
PUBLISHED: 08-27-2014
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Most biological nitrogen fixation is catalyzed by the molybdenum nitrogenase. This enzyme is a complex which contains the MoFe protein encoded by nifDK and the Fe protein encoded by nifH. In addition to nifHDK, nifHDK-like genes were found in some Archaea and Firmicutes, but their function is unclear.
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Composite photothermal platform of polypyrrole-enveloped Fe?O? nanoparticle self-assembled superstructures.
ACS Appl Mater Interfaces
PUBLISHED: 08-18-2014
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Photothermal nanoplatforms with small size, low cost, multifunctionality, good biocompatibility and in particular biodegradability are greatly desired in the exploration of novel diagnostic and therapeutic methodologies. Despite Fe3O4 nanoparticles (NPs) have been approved as safe clinical agents, the low molar extinction coefficient and subsequent poor photothermal performance shed the doubt as effective photothermal materials. In this paper, we demonstrate the fabrication of polypyrrole (PPy)-enveloped Fe3O4 NP superstructures with a spherical morphology, which leads to a 300-fold increase in the molar extinction coefficient. The basic idea is the optimization of Fe3O4 electronic structures. By controlling the self-assembly of Fe3O4 NPs, the diameters of the superstructures are tuned from 32 to 64 nm. This significantly enhances the indirect transition and magnetic coupling of Fe ions, thus increasing the molar extinction coefficient of Fe3O4 NPs from 3.65 × 10(6) to 1.31 × 10(8) M(-1) cm(-1) at 808 nm. The envelopment of Fe3O4 superstructures with conductive PPy shell introduces additional electrons in the Fe3O4 oscillation system, and therewith further enhances the molar extinction coefficient to 1.12 × 10(9) M(-1) cm(-1). As a result, the photothermal performance is greatly improved. Primary cell experiments indicate that PPy-enveloped Fe3O4 NP superstructures are low toxic, and capable to kill Hela cells under near-infrared laser irradiation. Owing to the low cost, good biocompatibility and biodegradability, the PPy-enveloped Fe3O4 NP superstructures are promising photothermal platform for establishing novel diagnostic and therapeutic methods.
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PPAR? ligand ciglitazone inhibits TNF?-induced ICAM-1 in human airway smooth muscle cells.
Biomed J
PUBLISHED: 08-14-2014
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Modification of human airway smooth muscle (ASM) function by proinflammatory cytokines has been regarded as a potential mechanism underlying bronchial hyperresponsiveness in asthma. Human ASM cells express intercellular adhesion molecule (ICAM)-1 in response to cytokines. Synthetic ligands for peroxisome proliferator-activated receptor (PPAR)? reportedly possess anti-inflammatory and immunomodulatory properties. In this study, we examined whether ciglitazone, a synthetic PPAR? ligand, can modulate the basal and tumor necrosis factor (TNF)?-induced ICAM1 gene expression in human ASM cells.
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Draft Genome Sequence of Listeria monocytogenes Strain LI0521 (syn. HPB7171), Isolated in 1983 during an Outbreak in Massachusetts Caused by Contaminated Cheese.
Genome Announc
PUBLISHED: 07-26-2014
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Listeria monocytogenes, a pathogenic food-borne bacterium, is the causative agent of both sporadic and outbreak cases of human listeriosis. Here, we present the genome sequence of L. monocytogenes reference strain LI0521, isolated during an outbreak involving contaminated cheese, which has been used as the model during several proteomic studies.
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Diversity-oriented combinatorial biosynthesis of benzenediol lactone scaffolds by subunit shuffling of fungal polyketide synthases.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-21-2014
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Combinatorial biosynthesis aspires to exploit the promiscuity of microbial anabolic pathways to engineer the synthesis of new chemical entities. Fungal benzenediol lactone (BDL) polyketides are important pharmacophores with wide-ranging bioactivities, including heat shock response and immune system modulatory effects. Their biosynthesis on a pair of sequentially acting iterative polyketide synthases (iPKSs) offers a test case for the modularization of secondary metabolic pathways into "build-couple-pair" combinatorial synthetic schemes. Expression of random pairs of iPKS subunits from four BDL model systems in a yeast heterologous host created a diverse library of BDL congeners, including a polyketide with an unnatural skeleton and heat shock response-inducing activity. Pairwise heterocombinations of the iPKS subunits also helped to illuminate the innate, idiosyncratic programming of these enzymes. Even in combinatorial contexts, these biosynthetic programs remained largely unchanged, so that the iPKSs built their cognate biosynthons, coupled these building blocks into chimeric polyketide intermediates, and catalyzed intramolecular pairing to release macrocycles or ?-pyrones. However, some heterocombinations also provoked stuttering, i.e., the relaxation of iPKSs chain length control to assemble larger homologous products. The success of such a plug and play approach to biosynthesize novel chemical diversity bodes well for bioprospecting unnatural polyketides for drug discovery.
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Investigation of metabolism and disposition of GSK1322322, a peptidase deformylase inhibitor, in healthy humans using the entero-test for biliary sampling.
Drug Metab. Dispos.
PUBLISHED: 05-28-2014
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GSK1322322 (N-((R)-2-(cyclopentylmethyl)-3-(2-(5-fluoro-6-((S)-hexahydropyrazino[2,1-c][1,4]oxazin-8(1H)-yl)-2-methylpyrimidin-4-yl)hydrazinyl)-3-oxopropyl)-N-hydroxy-formamide) is an antibiotic in development by GlaxoSmithKline. In this study, we investigated the metabolism and disposition of [(14)C]GSK1322322 in healthy humans and demonstrated the utility of the Entero-Test in a human radiolabel study. We successfully collected bile from five men using this easy-to-use device after single i.v. (1000 mg) or oral administration (1200 mg in a solution) of [(14)C]GSK1322322. GSK1322322 had low plasma clearance (23.6 liters/hour) with a terminal elimination half-life of ?4 hours after i.v. administration. After oral administration, GSK1322322 was readily and almost completely absorbed (time of maximal concentration of 0.5 hour; bioavailability 97%). GSK1322322 predominated in the systemic circulation (>64% of total plasma radioactivity). An O-glucuronide of GSK1322322 (M9) circulated at levels between 10% and 15% of plasma radioactivity and was pharmacologically inactive. Humans eliminated the radioactive dose in urine and feces at equal proportions after both i.v. and oral doses (?45%-48% each). Urine contained mostly unchanged GSK1322322, accounting for 30% of the dose. Bile contained mostly M9, indicating that glucuronidation was likely a major pathway in humans (up to 30% of total dose). In contrast, M9 was found in low amounts in feces, indicating its instability in the gastrointestinal tract. Therefore, without the Entero-Test bile data, the contribution of glucuronidation would have been notably underestimated. An unusual N-dehydroxylated metabolite (a secondary amide) of GSK1322322 was observed primarily in the feces and was most likely formed by gut microbes.
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Complications and predictors associated with persistent hemodynamic depression after carotid artery stenting.
Clin Neurol Neurosurg
PUBLISHED: 05-20-2014
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We aimed to investigate the complications and predictors associated with persistent hemodynamic depression (PHD) after carotid artery stenting (CAS). A total of 204 patients undergoing CAS in two centers between January 2011 and November 2013 were enrolled for study into two cohorts: PHD (systolic blood pressure <90 mm Hg and heart beat rate <60/min, which lasted more than 1h) and non-PHD according to their periprocedure detections. The complications were recorded and compared between the two groups. The predictors of PHD were analyzed by univariate analysis and logistic regression model. 43 patients developed PHD, which lasted for 17.22 h on average. The complications occurred in 9 patients of PHD group (angina pectoris 2, myocardial infarction 1, cerebral infarction 3, transient ischemic attack 2 and intestinal obstruction 1), which was significantly more than non- PHD group (angina pectoris 1, cerebral infarction 1, transient ischemic attack 5, p=0.001). Regression analysis revealed that diabetes, severe calcified plaque and a balloon dilation pressure of more than 8 atmospheres (atm) were the independent predictors for PHD after CAS. We concluded that PHD may be related to increased complications of CAS. Patients with diabetes, more severe calcified plaque and more balloon dilation pressure are more prone to develop PHD after CAS.
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Elevated plasma thrombomodulin and angiopoietin-2 predict the development of acute kidney injury in patients with acute myocardial infarction.
Crit Care
PUBLISHED: 05-02-2014
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Acute kidney injury (AKI) following acute myocardial infarction (AMI) is associated with unfavorable prognosis. Endothelial activation and injury were found to play a critical role in the development of both AKI and AMI. This pilot study aimed to determine whether the plasma markers of endothelial injury and activation could serve as independent predictors for AKI in patients with AMI.
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Selective synthesis of 4-(sulfonyl)-methyl-1H-pyrazoles and (E)-4,5-dihydro-1H-pyrazoles from N-allenic sulfonylhydrazones.
Org. Biomol. Chem.
PUBLISHED: 05-01-2014
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Selective synthesis of 4-(sulfonyl)-methyl-1H-pyrazoles and (E)-4,5-dihydro-1H-pyrazoles from N-allenic sulfonylhydrazones with sulfonyl group migrations has been developed. A key feature of these reactions is that the migrations of the sulfonyl groups to different positions can be controlled by changing the Lewis acids.
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[Research on association of BDNF gene Val66Met polymorphism with efficacy of antidepressants and plasma BDNF level].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 04-09-2014
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To assess the association of BDNF gene Val66Met polymorphism with efficacy of antidepressant treatment and plasma BDNF level.
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Removal of endobronchial malignant mass by cryotherapy improved performance status to receive chemotherapy.
ScientificWorldJournal
PUBLISHED: 04-06-2014
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Although malignant endobronchial mass (MEM) has poor prognosis, cryotherapy is reportedly a palliative treatment. Clinical data on postcryotherapy MEM patients in a university-affiliated hospital between 2007 and 2011 were evaluated. Survival curve with or without postcryotherapy chemotherapy and performance status (PS) improvement of these subjects were analyzed using the Kaplan-Meier method. There were 59 patients (42 males), with median age of 64 years (range, 51-76, and median performance status of 2 (interquartile range [IQR], 2-3). Postcryotherapy complications included minor bleeding (n = 12) and need for multiple procedures (n = 10), while outcomes were relief of symptoms (n = 51), improved PS (n = 45), and ability to receive chemotherapy (n = 40). The survival of patients with chemotherapy postcryotherapy was longer than that of patients without such chemotherapy (median, 534 versus 106 days; log-rank test, P = 0.007; hazard ratio, 0.25; 95% confidence interval, 0.10-0.69). The survival of patients with PS improvement postcryotherapy was longer than that of patients without PS improvement (median, 406 versus 106 days; log-rank test, P = 0.02; hazard ratio, 0.28; 95% confidence interval, 0.10-0.81). Cryotherapy is a feasible treatment for MEM. With better PS after cryotherapy, further chemotherapy becomes possible for patients to improve survival when MEM caused dyspnea and poor PS.
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Polypyrrole-coated chainlike gold nanoparticle architectures with the 808 nm photothermal transduction efficiency up to 70%.
ACS Appl Mater Interfaces
PUBLISHED: 04-04-2014
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Aqueous Au nanoparticles (NPs) are employed as the building blocks to construct chainlike self-assembly architectures, which greatly enhance the photothermal performance at 808 nm. Biocompatible polypyrrole (PPy) is further adopted as the package material to coat Au NP chains, producing stable photothermal agents. As a result of contributions from chainlike Au, the PPy shell, as well as the Au-PPy composite structures, the capability of photothermal transduction at 808 nm is greatly enhanced, represented by the high photothermal transduction efficiency up to 70%. Primary animal experiment proves that the current composite photothermal agents are efficient in inhibiting tumor growth under an 808 nm irradiation, showing the potentials for in vivo photothermal therapy.
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Hymenobacter kanuolensis sp. nov., a novel radiation-resistant bacterium.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 03-28-2014
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A Gram-reaction-negative, rod-shaped, non-motile, red-pigmented, radiation-resistant, aerobic bacterium designated T-3(T) was isolated from a soil sample from the Qinghai-Tibet Plateau in Tibet, China, after exposure to 10 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA sequences indicated that this isolate represented a novel member of the genus Hymenobacter. Sequence identities of the 16S rRNA gene of strain T-3(T) with the type strains of species of the genus Hymenobacter with validly published names range from 89% to 97%, and the most closely related species is Hymenobacter psychrotolerans Tibet-IIU11(T) (97%). The DNA-DNA relatedness between strain T-3(T) and H. psychrotolerans is 59.10%. The major fatty acids of strain T-3(T) were iso-C(15?:?0) (27.66%), summed feature 4 (iso-C(17?:?1)I and/or anteiso-C(17?:?1)B, 15.84%), anteiso-C(15?:?0) (14.08%) and summed feature 3 (C(16?:?1)?7c and/or C(16?:?1)?6c, 12.38%). The major menaquinone of strain T-3(T) was MK-7. Phosphatidylethanolamine (PE) was predominant in the polar lipid profile. The G+C content of the DNA of strain T-3(T) was 69.17 mol%. On the basis of the results of the polyphasic characterization presented in this study, it is concluded that strain T-3(T) represents a novel species of the genus Hymenobacter, for which the name Hymenobacter kanuolensis is proposed. The type strain is T-3(T) (?=?ACCC 05760(T)?=?KCTC 32407(T)).
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Arabidopsis ABA receptor RCAR1/PYL9 interacts with an R2R3-type MYB transcription factor, AtMYB44.
Int J Mol Sci
PUBLISHED: 03-22-2014
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Abscisic acid (ABA) signaling plays important roles in plant growth, development and adaptation to various stresses. RCAR1/PYL9 has been known as a cytoplasm and nuclear ABA receptor in Arabidopsis. To obtain further insight into the regulatory mechanism of RCAR1/PYL9, a yeast two-hybrid approach was performed to screen for RCAR1/PYL9-interacting proteins and an R2R3-type MYB transcription factor, AtMYB44, was identified. The interaction between RCAR1/PYL9 and AtMYB44 was further confirmed by glutathione S-transferase (GST) pull-down and bimolecular fluorescence complementation (BiFC) assays. Gene expression analysis showed that AtMYB44 negatively regulated the expression of ABA-responsive gene RAB18, in contrast to the opposite role reported for RCAR1/PYL9. Competitive GST pull-down assay and analysis of phosphatase activity demonstrated that AtMYB44 and ABI1 competed for binding to RCAR1/PYL9 and thereby reduced the inhibitory effect of RCAR1/PYL9 on ABI1 phosphatase activity in the presence of ABA in vitro. Furthermore, transient activation assay in protoplasts revealed AtMYB44 probably also decreased RCAR1/PYL9-mediated inhibition of ABI1 activity in vivo. Taken together, our work provides a reasonable molecular mechanism of AtMYB44 in ABA signaling.
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Molecular analysis of interactions between dendrimers and asymmetric membranes at different transport stages.
Soft Matter
PUBLISHED: 03-22-2014
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Studying dendrimer-biomembrane interactions is important for understanding drug and gene delivery. In this study, coarse-grained molecular dynamics simulations were performed to investigate the behaviors of polyamidoamine (PAMAM) dendrimers (G4 and G5) as they interacted with asymmetric membranes from different sides of the bilayer, thus mimicking different dendrimer transport stages. The G4 dendrimer could insert into the membrane during an equilibrated state, and the G5 dendrimer could induce pore formation in the membrane when the dendrimers interacted with the outer side (outer interactions) of an asymmetric membrane [with 10% dipalmitoyl phosphatidylserine (DPPS) in the inner leaflet of the membrane]. During the interaction with the inner side of the asymmetric membrane (inner interactions), the G4 and G5 dendrimers only adsorbed onto the membrane. As the membrane asymmetry increased (e.g., increased DPPS percentage in the inner leaflet of the membrane), the G4 and G5 dendrimers penetrated deeper into the membrane during the outer interactions and the G4 and G5 dendrimers were adsorbed more tightly onto the membrane for the inner interactions. When the DPPS content reached 50%, the G4 dendrimer could completely penetrate through the membrane from the outer side to the inner side. Our study provides molecular understanding and reference information about different dendrimer transport stages during drug and gene delivery.
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Evaluation of a levonorgestrel-releasing intrauterine system for treating endometrial hyperplasia in patients with polycystic ovary syndrome.
Gynecol. Obstet. Invest.
PUBLISHED: 03-18-2014
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To evaluate the use of a levonorgestrel-releasing intrauterine system (LNG-IUS) for treating endometrial hyperplasia in patients with polycystic ovary syndrome (PCOS).
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Nation wide epidemiological survey of primary palmar hyperhidrosis in the People's Republic of China.
Clin. Auton. Res.
PUBLISHED: 03-17-2014
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To investigate the prevalence and epidemiological characteristics of primary palmar hyperhidrosis (PPH) among adolescents in PR China.
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Association analysis of COMT/MTHFR polymorphisms and major depressive disorder in Chinese Han population.
J Affect Disord
PUBLISHED: 03-05-2014
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In several previous biochemical and genetic studies, the Val158Met polymorphism of the gene encoding catechol-O-methyltransferase (COMT) and the C677T polymorphism of Methylenetetrahydrofolate reductase (MTHFR) have been suggested to be involved in the pathogenesis as well as the treatment response of major depressive disorder (MDD), but the results have been inconsistent. In this study, we investigate the association of COMT/MTHFR and their interactions with MDD and antidepressant response in Chinese Han population.
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Rapid screening for sickle cell disease by polymerase chain reaction-high resolution melting analysis.
Mol Med Rep
PUBLISHED: 03-05-2014
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Each year, ~300,000 individuals with sickle cell disease (SCD), a hemoglobinopathy caused by ?-globin gene mutation, are born, and >75% of those are in Africa. The present study examined 511 individuals on the island of Bioko (Equatorial Guinea) and attempted to establish a method for rapid sickle cell disease screening. Following DNA extraction and polymerase chain reaction (PCR) amplification, high resolution melting (HRM) analysis was used to assess the specificity of fluorescence signals of the PCR products and to differentiate various genotypes of these products. The analytical results of HRM were validated using DNA sequencing. By HRM analysis, 80 out of 511 samples were classified as hemoglobin S (Hb S) heterozygotes, while 431 out of 511 samples were classified as wild-type. No mutant homozygote was identified. DNA sequencing indicated that within the 431 wild-type samples as indicated by HRM analysis, one case was actually a Hb S heterozygote and another case was a rare hemoglobin S-C genotype (sickle-hemoglobin C disease). One out of 80 suspected Hb S heterozygotes as indicated by HRM was confirmed as wild-type by DNA sequencing and the results of residual 508 cases were consistent for HRM analysis and sequencing. In conclusion, HRM analysis is a simple, high-efficiency approach for Hb S screening and is useful for early diagnosis of SCD and particularly suitable for application in the African area.
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DDX3X regulates cell survival and cell cycle during mouse early embryonic development.
J Biomed Res
PUBLISHED: 03-03-2014
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DDX3X is a highly conserved DEAD-box RNA helicase that participates in RNA transcription, RNA splicing, and mRNA transport, translation, and nucleo-cytoplasmic transport. It is highly expressed in metaphase II (MII) oocytes and is the predominant DDX3 variant in the ovary and embryo. However, whether it is important in mouse early embryo development remains unknown. In this study, we investigated the function of DDX3X in early embryogenesis by cytoplasmic microinjection with its siRNA in zygotes or single blastomeres of 2-cell embryos. Our results showed that knockdown of Ddx3x in zygote cytoplasm led to dramatically diminished blastocyst formation, reduced cell numbers, and an increase in the number of apoptotic cells in blastocysts. Meanwhile, there was an accumulation of p53 in RNAi blastocysts. In addition, the ratio of cell cycle arrest during 2-cell to 4-cell transition increased following microinjection of Ddx3x siRNA into single blastomeres of 2-cell embryos compared with control. These results suggest that Ddx3x is an essential gene associated with cell survival and cell cycle control in mouse early embryos, and thus plays key roles in normal embryo development.
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Dissecting the mechanism of carotid atherosclerosis from the perspective of regulation.
Int. J. Mol. Med.
PUBLISHED: 02-20-2014
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Carotid atherosclerosis is a chronic inflammatory disease of the arterial wall. The present study aimed to identify changes in the gene expression and regulatory factors for atherosclerotic plaques of carotid atherosclerosis from an early to an advanced stage. The original data were downloaded from the NCBI GEO database under accession no. GSE28829. Differentially expressed genes (DEGs) were detected by the Robust Multiarray Average (RMA). The enriched Gene Ontology (GO) terms and pathways for DEGs using DAVID were subsequently identified. The transcriptional and microRNA (miRNA) regulatory network were constructed for the DEGs. Cis-regulatory signals were also investigated. More genes were activated in the advanced stage compared with the early stage. IGHG1 and SPP1 were upregulated, while MYBL1 and PLD were downregulated. The upregulated genes in the advanced stage were involved in atherosclerosis?related GO terms such as immune, vascular and cell movement homeostasis. The DEGs were significantly enriched in cell adhesion molecules (CAMs) and the focal adhesion pathway. MMP9 and CFL2 played key roles in the transcriptional regulatory network. Moreover, miR-328 was identified as one of the hubs in the miRNA regulatory network. The results may therefore be used to determine the mechanism involved in carotid atherosclerosis.
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Zonal rate model for axial and radial flow membrane chromatography, part II: model-based scale-up.
Biotechnol. Bioeng.
PUBLISHED: 01-31-2014
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Membrane chromatography (MC) systems are finding increasing use in downstream processing trains for therapeutic proteins due to the unique mass-transfer characteristics they provide. As a result, there is increased need for model-based methods to scale-up MC units using data collected on a scaled-down unit. Here, a strategy is presented for MC unit scale-up using the zonal rate model (ZRM). The ZRM partitions an MC unit into virtual flow zones to account for deviations from ideal plug-flow behavior. To permit scale-up, it is first configured for the specific device geometry and flow profiles within the scaled-down unit so as to achieve decoupling of flow and binding related non-idealities. The ZRM is then configured for the preparative-scale unit, which typically utilizes markedly different flow manifolds and membrane architecture. Breakthrough is first analyzed in both units under non-binding conditions using an inexpensive tracer to independently determine unit geometry related parameters of the ZRM. Binding related parameters are then determined from breakthrough data on the scaled-down MC capsule to minimize sample requirements. Model-based scale-up may then be performed to predict band broadening and breakthrough curves on the preparative-scale unit. Here, the approach is shown to be valid when the Pall XT140 and XT5 capsules serve as the preparative and scaled-down units, respectively. In this case, scale-up is facilitated by our finding that the distribution of linear velocities through the membrane in the XT140 capsule is independent of the feed flow rate and the type of protein transmitted. Introduction of this finding into the ZRM permits quantitative predictions of breakthrough over a range of industrially relevant operating conditions.
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Chronic obstructive pulmonary disease in stage I non-small cell lung cancer that underwent anatomic resection: the role of a recurrence promoter.
COPD
PUBLISHED: 01-29-2014
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Despite the use of anatomic resection, the post-surgical recurrence rate remains high in early-stage non-small cell lung cancer (NSCLC). Chronic inflammation plays a role in the mechanism that promotes tumor initiation. This study aimed to investigate the association between recurrence outcome and chronic inflammation-related co-morbidities in early-stage resected NSCLC.
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Quantitative proteomics analysis of altered protein expression in the placental villous tissue of early pregnancy loss using isobaric tandem mass tags.
Biomed Res Int
PUBLISHED: 01-28-2014
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Many pregnant women suffer miscarriages during early gestation, but the description of these early pregnancy losses (EPL) can be somewhat confusing because of the complexities of early development. Thus, the identification of proteins with different expression profiles related to early pregnancy loss is essential for understanding the comprehensive pathophysiological mechanism. In this study, we report a gel-free tandem mass tags- (TMT-) labeling based proteomic analysis of five placental villous tissues from patients with early pregnancy loss and five from normal pregnant women. The application of this method resulted in the identification of 3423 proteins and 19647 peptides among the patient group and the matched normal control group. Qualitative and quantitative proteomic analysis revealed 51 proteins to be differentially abundant between the two groups (? 1.2-fold, Student's t-test, P < 0.05). To obtain an overview of the biological functions of the proteins whose expression levels altered significantly in EPL group, gene ontology analysis was performed. We also investigated the twelve proteins with a difference over 1.5-fold using pathways analysis. Our results demonstrate that the gel-free TMT-based proteomic approach allows the quantification of differences in protein expression levels, which is useful for obtaining molecular insights into early pregnancy loss.
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Halomonas huangheensis sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 01-16-2014
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A novel, Gram-stain-negative, aerobic, rod-shaped, non-motile and moderately halophilic bacterium, designated strain BJGMM-B45(T), was isolated from a saline-alkali soil collected from Shandong Province, China. Growth of strain BJGMM-B45(T) occurred at 10-45 °C (optimum, 30 °C) and pH 5.0-12.0 (optimum, pH 7.0) on Luria-Bertani agar medium with 1-20?% (w/v) NaCl (optimum, 7-10?%). The predominant respiratory quinone was Q-9. The major cellular fatty acids (>5?%) were C18?:?1?7c, C16?:?0, C19?:?0 cyclo ?8c, summed feature 3, C12?:?0 3-OH and C12?:?0. The genomic DNA G+C content was 57.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BJGMM-B45(T) belonged to the genus Halomonas in the class Gammaproteobacteria. The closest relatives were Halomonas cupida DSM 4740(T) (98.2?% 16S rRNA gene sequence similarity) and Halomonas denitrificans M29(T) (97.8?%). Levels of DNA-DNA relatedness between strain BJGMM-B45(T) and Halomonas cupida CGMCC 1.2312(T) and Halomonas denitrificans DSM 18045(T) were 57.0 and 58.9?%, respectively. On the basis of phenotypic, chemotaxonomic and phylogenetic features, strain BJGMM-B45(T) is considered to represent a novel species of the genus Halomonas, for which the name Halomonas huangheensis sp. nov. is proposed. The type strain is BJGMM-B45(T) (?=?ACCC 05850(T)?=?KCTC 32409(T)).
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Base-catalyzed N-N bond cleavage of hydrazones: synthesis of ?-amino ketones.
Chem Asian J
PUBLISHED: 01-07-2014
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An efficient Cs2CO3-promoted synthesis of ?-amino ketones using hydrazines, aldehydes, and ?-haloketones as starting materials through a cascade condensation/nucleophilic substitution/N-N bond cleavage route is developed. The carbonyl group plays a key role in this novel N-N bond cleavage process.
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Basis of aggravated hepatic lipid metabolism by chronic stress in high-fat diet-fed rat.
Endocrine
PUBLISHED: 01-06-2014
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Our previous study has demonstrated that long-term stress, known as chronic stress (CS), can aggravate nonalcoholic fatty liver disease in high-fat diet (HFD)-fed rat. In this study, we tried to figure out which lipid metabolic pathways were impacted by CS in the HFD-fed rat. Male Sprague-Dawley rats (6 weeks of age, n = 8 per group) were fed with either standard diet or HFD with or without CS exposure for 8 weeks. Hepatic lipidosis, biochemical, hormonal, and lipid profile markers in serum and liver, and enzymes involved in de novo lipogenesis (DNL) of fatty acids (FAs) and cholesterol, ?-oxidation, FAs uptake, triglycerides synthesis, and very low-density lipoprotein (VLDL) assembly in the liver were detected. CS exposure reduced hepatic lipidosis but further elevated hepatic VLDL content with aggravated dyslipidemia in the HFD-fed rats. There was a synergism between CS and HFD on VLDL production and dyslipidemia. PCR and western blot assays showed that CS exposure significantly promoted hepatic VLDL assembly in rats, especially in the HFD-fed rats, while it had little impact on DNL, ?-oxidation, FAs uptake, and triglycerides synthesis in the HFD-fed rats. This phenomenon was in accordance with elevated serum glucocorticoid level. The critical influence of CS exposure on hepatic lipid metabolism in the HFD-fed rats is VLDL assembly which might be regulated by glucocorticoid.
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Characterization of Lung Function Impairment in Adults with Bronchiectasis.
PLoS ONE
PUBLISHED: 01-01-2014
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Characteristics of lung function impairment in bronchiectasis is not fully understood.
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Tumor-associated macrophages in stage IIIA pN2 non-small cell lung cancer after neoadjuvant chemotherapy and surgery.
Am J Transl Res
PUBLISHED: 01-01-2014
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Most of the patients with stage IIIA pN2 non-small cell lung cancer (NSCLC) develop recurrence after surgery. It is not clear whether post neoadjuvant chemotherapy tumor-associated macrophages is associated with recurrence.
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High resolution melting analysis: a rapid screening and typing tool for common ?-thalassemia mutation in Chinese population.
PLoS ONE
PUBLISHED: 01-01-2014
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?-thalassemia is a common inherited disorder worldwide including southern China, and at least 45 distinct ?-thalassemia mutations have been identified in China. High-resolution melting (HRM) assay was recently introduced as a rapid, inexpensive and effective method for genotyping. However, there was no systemic study on the diagnostic capability of HRM to identify ?-thalassemia. Here, we used an improved HRM method to screen and type 12 common ?-thalassemia mutations in Chinese, and the rapidity and reliability of this method was investigated. The whole PCR and HRM procedure could be completed in 40 min. The heterozygous mutations and 4 kinds of homozygous mutations could be readily differentiated from the melting curve except c.-78A>G heterozygote and c.-79A>G heterozygote. The diagnostic reliability of this HRM assay was evaluated on 756 pre-typed genomic DNA samples and 50 cases of blood spots on filter paper, which were collected from seven high prevalent provinces in southern China. If c.-78A>G heterozygote and c.-79A>G heterozygote were classified into the same group (c.-78&79 A>G heterozygote), the HRM method was in complete concordance with the reference method (reverse dot blot/DNA-sequencing). In a conclusion, the HRM method appears to be an accurate and sensitive method for the rapid screening and identification of ?-thalassemia mutations. In the future, we suggest this technology to be used in neonatal blood spot screening program. It could enlarge the coverage of ?-thalassemia screening program in China. At the same time, its value should be confirmed in prospectively clinical and epidemiological studies.
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Molecular epidemiological characterization and health burden of thalassemia in Jiangxi Province, P. R. China.
PLoS ONE
PUBLISHED: 01-01-2014
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Thalassemia is the most common inherited disease in southern China. However, this disorder is usually ignored by Jiangxi provincial health system and government due to lack of epidemiological data.
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Macrolide therapy in adults and children with non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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A systematic review and meta-analysis was conducted to evaluate the efficacy and safety of macrolide therapy in adults and children with bronchiectasis.
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Clinical characteristics and treatment outcomes of patients with low- and high-concentration isoniazid-monoresistant tuberculosis.
PLoS ONE
PUBLISHED: 01-01-2014
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Isoniazid (INH) resistance is now the most common type of tuberculosis (TB) infection resistance worldwide. The aim of this study was to evaluate the clinical characteristics and treatment outcomes of patients with low- and high-concentration INH-monoresistant TB.
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[Study on biological characteristics of Cordyceps ramosa mycelia].
Zhong Yao Cai
PUBLISHED: 12-31-2013
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To study the biological characteristics of Cordyceps ramosa mycelia.
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Polypyrrole-Enveloped Pd and Fe3O4 Nanoparticle Binary Hollow and Bowl-Like Superstructures as Recyclable Catalysts for Industrial Wastewater Treatment.
ACS Appl Mater Interfaces
PUBLISHED: 11-27-2013
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Metal and metal-oxide nanoparticles (NPs) are promising catalysts for dye degradation in wastewater treatment despite the challenges of NP recovery and recycling. In this study, water-dispersible NP superstructures with spherical morphology were constructed from hydrophobic Pd and Fe3O4 NPs by virtue of the oil droplets in an oil-in-water microemulsion as templates. Control of the evaporation rate of organic solvents in the oil droplets produces solid, hollow, and bowl-like superstructures. The component Fe3O4 and in particular Pd NPs can catalyze H2O2 degradation to create hydroxyl radicals and therewith degrade various dyes, and the magnetic Fe3O4 NPs also permit recycling of the superstructures with a magnet. Because the hollow and bowl-like superstructures increase the contact area of the NPs with their surroundings in comparison to solid superstructures, the catalytic activity is greatly enhanced. To improve the structural stability, the superstructures were further enveloped with a thin polypyrrole (PPy) shell, which does not weaken the catalytic activity. Because the current method is facile and feasible to create recyclable catalysts, it will promote the practicability of NP catalysts in treating industrial polluted water.
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Characteristics of Single Large-Conductance Ca2+-Activated K+ Channels and Their Regulation of Action Potentials and Excitability in vagal Cardiac Motoneurons.
Am. J. Physiol., Cell Physiol.
PUBLISHED: 11-06-2013
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Large-conductance Ca(2+)-activated K(+) channels (BK) regulate action potential (AP) properties and excitability in many central neurons. However, the properties and functional role of BK channels of parasympathetic cardiac motoneurons (PCMNs) in the nucleus ambiguus (NA) have not yet been well characterized. In this study, the tracer X-rhodamine-5 (and 6)-isothiocyanate (XRITC) was injected into the pericardial sac to retrogradely label PCMNs in FVB mice at 7-9 days postnatal. Two days later, XRITC-labeled PCMNs in brain stem slices were identified. Using excised patch single-channel recordings, we identified voltage-gated and Ca(2+)-dependent BK channels in PCMNs. The majority of BK channels exhibited persistent channel opening during voltage holding. These BK channels had a conductance of 237 pS. The channel dwell time increased exponentially as the membrane potential depolarized. Occasionally, some BK channels showed a transient channel opening or fast inactivation. Using whole-cell voltage clamp, we found that BK channel mediated outward currents had both transient and persistent components. Using whole-cell current clamp, we found that application of IBTX increased spike half-width in single APs and trains, and reduced the spike frequency-dependent AP broadening in trains. In addition, BK channel blockade suppressed fast afterhyperpolarization (fAHP) amplitude following APs. Furthermore, BK channel blockade significantly decreased spike frequency and spike frequency adaption (SFA). Collectively, these results demonstrate that PCMNs have BK channels which significantly regulate AP repolarization, fAHP, SFA and spike frequency. We conclude that activation of BK channels underlies one of the mechanisms for facilitation of PCMN excitability.
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[Spectroscopic diagnosis of dielectric barrier discharge in long gap under low presssure].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-29-2013
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In the present paper, a dielectric barrier discharge (DBD) plasma was generated at low pressure in a DBD device with the eletrode distance of 10cm and using Ar as working gas. The changes in electronic temperature and density in the discharge cavum were studied by means of emission spectrometry. The changes in electronic temperature measured by using corona model were obtained. The variations in electronic density were analyzed using 750.4 nm line intensity. It was found that the plasma electronic temperature and density is various at different positions in the discharge cavum. With the measuring point moving from cathode to anode, the electronic temperature firstly increases slowly, then decreases quickly. While the electronic density increases slowly at first, and then rapidly.
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Endobronchial ultrasound-guided transbronchial biopsy and brushing: a comparative evaluation for the diagnosis of peripheral pulmonary lesions.
Eur J Cardiothorac Surg
PUBLISHED: 09-27-2013
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The diagnosis of peripheral pulmonary lesions (PPLs) often involves endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB), washing and brushing. Certain echoic features of PPL have been associated with biopsy yield. This study compared yields of TBB and bronchial washing (TBBW) with those of TBBW plus bronchial brushing and analysed the associations between clinical and echoic features and yield.
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Oligonucleotide-linked gold nanoparticle aggregates for enhanced sensitivity in lateral flow assays.
Lab Chip
PUBLISHED: 09-24-2013
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Lateral flow assays (LFAs) as rapid analytical techniques promise to be widely used in point-of-care (POC) diagnostics because of their affordability and simplicity. However, LFAs still suffer from low sensitivity in detection of various biomarkers, e.g., nucleic acids. In this study, we developed a simple and general one-step signal amplification strategy, which employed oligonucleotide-linked gold nanoparticle (AuNP) aggregates to enhance the sensitivity in nucleic acid lateral flow (NALF) assays. Using a nucleic acid sequence of human immunodeficiency virus type 1 (HIV-1) as a model analyte, we observed that the detection limit of the developed NALF assay was 0.1 nM, which was improved by 2.5-fold compared with that of a non-signal amplification approach. The methodology described here could be used to detect a broad range of nucleic acids, and the general signal amplification approach could be potentially adopted in other types of LFAs.
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Sphingobacterium arenae sp. nov., isolated from sandy soil in Xinjiang of China.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 09-19-2013
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A novel Gram-negative, non-motile, non-spore-forming, aerobic short rod-bacterium designated strain H-12T was isolated from mixed sandy soil sample of Xinjiang, China. Growth of strain H-12T occurred at 20-37 °C (optimum, 30 °C), pH 7.0-11.0 (optimum, pH 8.5) on TGY medium with 0-5 % (w/v) NaCl. The 16S rRNA gene sequence of strain H-12T has a similarity with Sphingobacterium composti DSM 18850T (90.0%) and Sphingobacterium thermophilum CKTNT (91.0%). The predominant isoprenoid quinone of strain H-12T is MK-7 and the major polar lipid is phosphatidylethanolamine. The predominant cellular fatty acids are C16 : 1 ?7c and/or C16 : 1 ?6c, iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 0, C16 : 0 3-OH, iso-C15 : 0 3-OH. The DNA G+C content of strain H-12T is 44.15 mol%. On the basis of phenotypic, genetic and phylogenetic data, strain H-12T may be classified as a novel species of the genus Sphingobacterium, for which the name Sphingobacterium sandensis sp. nov. is proposed. The type strain is H-12T (= ACCC 05758T = KCTC 32294T).
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Controlled growth of atomically thin In2Se3 flakes by van der Waals epitaxy.
J. Am. Chem. Soc.
PUBLISHED: 08-28-2013
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The controlled production of high-quality atomically thin III-VI semiconductors poses a challenge for practical applications in electronics, optoelectronics, and energy science. Here, we exploit a controlled synthesis of single- and few-layer In2Se3 flakes on different substrates, such as graphene and mica, by van der Waals epitaxy. The thickness, orientation, nucleation site, and crystal phase of In2Se3 flakes were well-controlled by tuning the growth condition. The obtained In2Se3 flakes exhibit either semiconducting or metallic behavior depending on the crystal structures. Meanwhile, field-effect transistors based on the semiconducting In2Se3 flakes showed an efficient photoresponse. The controlled growth of atomically thin In2Se3 flakes with diverse conductivity and efficient photoresponsivity could lead to new applications in photodetectors and phase change memory devices.
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Chronic cough and obstructive sleep apnoea in a sleep laboratory-based pulmonary practice.
Cough
PUBLISHED: 08-03-2013
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Obstructive sleep apnoea (OSA) has recently been identified as a possible aetiology for chronic cough. The aim of this study was to compare the incidence of chronic cough between patients with and without OSA and the impact of continuous positive airway pressure (CPAP) treatment in resolving chronic cough.
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Gelatin nanostructured lipid carriers-mediated intranasal delivery of basic fibroblast growth factor enhances functional recovery in hemiparkinsonian rats.
Nanomedicine
PUBLISHED: 07-27-2013
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Lipid nanoparticles with solid matrix have been given increasing attention due to their biodegradable status and ability to entrap a variety of biologically active compounds. In this study, new phospholipid-based gelatin nanoparticles encapsulating basic fibroblast growth factor (bFGF) were developed to target the brain via nasal administration. Treatment effects were assessed by quantifying rotational behavior, monoamine neurotransmitter levels and tyrosine hydroxylase expression in 6-hydroxydopamine induced hemiparkinsonian rats. The gelatin nanostructured lipid carriers (GNLs) were prepared by a water-in-water emulsion method and then freeze-dried. The GNLs possessed better profile than gelatin nanoparticles (GNs), with particle size 143±1.14nm and Zeta potential -38.2±1.2mV. The intranasal GNLs efficiently enriched exogenous bFGF in olfactory bulb and striatum without adverse impact on the integrity of nasal mucosa and showed obvious therapeutic effects on hemiparkinsonian rats. Thus, GNLs are attractive carriers for nose-to-brain drug delivery, especially for unstable macromolecular drugs such as bFGF.
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A method for detecting forward scattering signals on-chip with a photonic-microfluidic integrated device.
Biomed Opt Express
PUBLISHED: 07-01-2013
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A photonic integrated microfluidic device is demonstrated to perform optical excitation and forward scatter collection all on-chip in a planar format. Integrated on-chip optics formed a tailored beam geometry for optimal excitation of particles while a special design modification allowed for on-chip forward collection with the beam shaping capabilities. A notch was placed in the lens system that caused a dark spot on the facet of a collection waveguide while not affecting the beam geometry at the point of interrogation. The modified device with the ability to form a 10 ?m beam geometry was demonstrated to detect the forward scatter from blank 5 ?m diameter polystyrene beads. Free-space collection of side scatter signals was performed simultaneously with the on-chip collection and the designs demonstrated and enhanced SNR while the reliability of detection was determined to be appropriate for many applications. Excellent performance was confirmed via a false positive rate of 0.4%, a missed events rate of 6.8%, and a coincident rate of 96.3% as determined between simultaneously performed free-space and on-chip detection schemes.
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Molecular epidemiological survey of hemoglobinopathies in the Wuxi region of Jiangsu Province, eastern China.
Hemoglobin
PUBLISHED: 06-27-2013
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In order to determine the prevalence and molecular characterization of hemoglobinopathies in the Wuxi region of Jiangsu Province in the Peoples Republic of China (PRC), a total of 10,297 healthy people selected from a regional hospital were screened. Hemoglobin (Hb) electrophoresis, complete blood cell (CBC) count, polymerase chain reaction (PCR), DNA sequencing, reverse dot-blot and multiplex ligation-dependent probe amplification (MLPA) were used to detect Hb variants, thalassemias and hereditary persistence of fetal Hb (HPFH). Two thousand and twenty-one adult subjects were screened for thalassemia, five cases were identified as ?-thalassemia (?-thal) carriers including three cases of the -?(3.7) (rightward) deletion, one case of the - -(SEA) deletion and one case of ?-thal [IVS-II-654 (C>T), (HBB: c.316-197C>T)]. The incidence of Hb variants, thalassemia and HPFH/??-thal were 0.136% (14/10,297), 0.25% (5/2021) and 0.0001% (1/10,297), respectively. Eight genotypes of Hb variants were found, including Hb E [?26(B8)Glu?Lys, GAG>AAG; HBB: c.79G>A], Hb J-Bangkok [?56(D7)Gly?Asp (GGC>GAC); HBB; c.170G>A], Hb G-Coushatta [?22(4)Glu?Ala (GAA>GCA); HBB: c.68A>C], Hb Queens [?34(B15)Leu?Arg (CTG>CGG) (?2 or ?1); HBA2: c.104T>G (or HBA1)], Hb I [?16(A14)Lys?Glu, AAG>GAG (?1); HBA1: c.49A>G], Hb Beijing [?16(A14)Lys?Asn (AAG>AAC or AAT) (?2 or ?1); HBA2: c.51G>C (or HBA1) or 51G>T (or HBA1)], Hb Ube-2 [?68(E17)Asn?Asp (AAC>GAC) (?2 or ?1); HBA2: c.205A>G (or HBA1)] and Hb G-Taipei [?22(B4)Glu?Gly (GAA>GGA); HBB: c.68A>G]. A Sicilian ??(0)-thal, identified for the first time in Asia, was also found in this survey.
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Advances in the understanding of nanomaterial-biomembrane interactions and their mathematical and numerical modeling.
Nanomedicine (Lond)
PUBLISHED: 06-05-2013
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The widespread application of nanomaterials (NMs), which has accompanied advances in nanotechnology, has increased their chances of entering an organism, for example, via the respiratory system, skin absorption or intravenous injection. Although accumulating experimental evidence has indicated the important role of NM-biomembrane interaction in these processes, the underlying mechanisms remain unclear. Computational techniques, as an alternative to experimental efforts, are effective tools to simulate complicated biological behaviors. Computer simulations can investigate NM-biomembrane interactions at the nanoscale, providing fundamental insights into dynamic processes that are challenging to experimental observation. This paper reviews the current understanding of NM-biomembrane interactions, and existing mathematical and numerical modeling methods. We highlight the advantages and limitations of each method, and also discuss the future perspectives in this field. Better understanding of NM-biomembrane interactions can benefit various fields, including nanomedicine and diagnosis.
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Efficacy, Safety, and Tolerability of Telcagepant in the Treatment of Acute Migraine: A meta-Analysis.
Pain Pract
PUBLISHED: 05-31-2013
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Although triptans are widely used for treating acute migraine, they are contraindicated or not effective in a large proportion of patients. Hence, alternative treatments are needed. Calcitonin gene-related peptide receptor antagonists, such as telcagepant, have been under investigation as a treatment for acute migraine. A meta-analysis of the efficacy of telcagepant vs. placebo and triptans (zolmitriptan or rizatriptan) was performed. Randomized controlled trials were indentified from databases using the following search terms: migraine; calcitonin gene-related peptide; calcitonin gene-related peptide receptor antagonists; efficacy; safety, and telcagepant. The primary outcome measure was pain freedom 2 hours after first treatment. The secondary outcome measure was pain relief 2 hours after first treatment. Eight trials were included in the meta-analysis (telcagepant = 4011 participants). The difference in pain freedom at 2 hours significantly favored telcagepant over placebo (odds ratio = 2.70, 95% confidence interval = 2.27-3.21, P < 0.001) and triptans over telcagepant (odds ratio = 0.68, 95% confidence interval = 0.56-0.83, P < 0.001). The difference in pain relief at 2 hours significantly favored telcagepant over placebo (odds ratio = 2.48, 95% confidence interval = 2.18-2.81, P < 0.001). The difference in pain relief at 2 hours did not significantly favor telcagepant over triptans or vice versa (odds ratio = 0.76, 95% confidence interval = 0.57-1.01, P = 0.061). These findings indicate that telcagepant can be effective for treating acute migraine. Calcitonin gene-related peptide receptor antagonists represent a potentially important alternative means of treating acute migraine.
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Proteomic identification of Listeria monocytogenes surface-associated proteins.
Proteomics
PUBLISHED: 05-23-2013
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This study aimed to identify proteins exposed on the surface of Listeria monocytogenes cells for diagnostic reagent development. Brief trypsin treatment of L. monocytogenes cells followed by peptide separation and identification by nano-LC and online-MS/MS was performed. In parallel, as a negative control, proteins secreted into the digest buffer as well as proteins from cell lysis were identified. One hundred and seventy-four proteins were identified in at least two of three trials in either the negative control or during cell digest. Nineteen surface, 21 extracellularly secreted, 132 cytoplasmic, and two phage proteins were identified. Immunofluorescence microscopy of L. monocytogenes cells revealed the surface localization of two potential candidates for L. monocytogenes isolation and detection: lipoprotein LMOf2365_0546 and PBPD1 (LMOf2365_2742). In this report, we present the first data set of surface-exposed L. monocytogenes proteins currently available. The data have been deposited to the ProteomeXchange Consortium with identifier PXD000035.
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Low prevalence of HPV in male sexual partners of HR-HPV infected females and low concordance of viral types in couples in Eastern Guangdong.
Asian Pac. J. Cancer Prev.
PUBLISHED: 05-18-2013
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To investigate the prevalence of genital high-risk human papillomavirus (HR-HPV) in male sexual partners of HR-HPV infected women and the concordance of viral types in couples in China, and comprehend the role of men play in HPV transmission to women.
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Scattering detection using a photonic-microfluidic integrated device with on-chip collection capabilities.
Electrophoresis
PUBLISHED: 04-19-2013
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SU-8-based photonic-microfluidic integrated devices with on-chip beam shaping and collection capabilities were demonstrated in a scattering detection and counting application. Through the proper deployment of the tailored beam geometries via the on-chip excitation optics, excellent CV values were measured for 1, 2, and 5 ?m blank beads, 16.4, 11.0, and 12.5%, respectively, coupled with a simple free-space optical detection scheme. The performance of these devices was found dependent on the combination of on-chip, lens-shaped beam geometry and bead size. While very low CVs were obtained when the combination was ideal, a nonideal combination could still result in acceptable CVs for flow cytometry; the reliability was confirmed via devices being able to resolve separate populations of 2.0 and 5.0 ?m beads from their mixture with low CV values of 15.9 and 18.5%, respectively. On-chip collection using integrated on-chip optical waveguides was shown to be very reliable in comparison with a free-space collection scheme, yielding a coincident rate of 94.2%. A CV as low as 19.2% was obtained from the on-chip excitation and collection of 5 ?m beads when the on-chip lens-shaped beam had a 6.0-?m beam waist.
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Computational fluid dynamic simulation of axial and radial flow membrane chromatography: mechanisms of non-ideality and validation of the zonal rate model.
J Chromatogr A
PUBLISHED: 04-01-2013
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Membrane chromatography (MC) is increasingly being used as a purification platform for large biomolecules due to higher operational flow rates. The zonal rate model (ZRM) has previously been applied to accurately characterize the hydrodynamic behavior in commercial MC capsules at different configurations and scales. Explorations of capsule size, geometry and operating conditions using the model and experiment were used to identify possible causes of inhomogeneous flow and their contributions to band broadening. In the present study, the hydrodynamics within membrane chromatography capsules are more rigorously investigated by computational fluid dynamics (CFD). The CFD models are defined according to precisely measured capsule geometries in order to avoid the estimation of geometry related model parameters. In addition to validating the assumptions and hypotheses regarding non-ideal flow mechanisms encoded in the ZRM, we show that CFD simulations can be used to mechanistically understand and predict non-binding breakthrough curves without need for estimation of any parameters. When applied to a small-scale axial flow MC capsules, CFD simulations identify non-ideal flows in the distribution (hold-up) volumes upstream and downstream of the membrane stack as the major source of band broadening. For the large-scale radial flow capsule, the CFD model quantitatively predicts breakthrough data using binding parameters independently determined using the small-scale axial flow capsule, identifying structural irregularities within the membrane pleats as an important source of band broadening. The modeling and parameter determination scheme described here therefore facilitates a holistic mechanistic-based method for model based scale-up, obviating the need of performing expensive large-scale experiments under binding conditions. As the CFD model described provides a rich mechanistic analysis of membrane chromatography systems and the ability to explore operational space, but requires detailed knowledge of internal capsule geometries and has much greater computational requirements, it is complementary to the previously described strengths and uses of the ZRM for process analysis and design.
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Nocturnal CPAP improves walking capacity in COPD patients with obstructive sleep apnoea.
Respir. Res.
PUBLISHED: 02-11-2013
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BACKGROUND: Exercise limitation is an important issue in patients with chronic obstructive pulmonary disease (COPD), and it often co-exists with obstructive sleep apnoea (overlap syndrome). This study examined the effects of nocturnal continuous positive airway pressure (CPAP) treatment on walking capacity in COPD patients with or without obstructive sleep apnoea. METHODS: Forty-four stable moderate-to-severe COPD patients were recruited and completed this study. They all underwent polysomnography, CPAP titration, accommodation, and treatment with adequate pressure. The incremental shuttle walking test was used to measure walking capacity at baseline and after two nights of CPAP treatment. Urinary catecholamine and heart rate variability were measured before and after CPAP treatment. RESULTS: After two nights of CPAP treatment, the apnoea-hypopnoea index and oxygen desaturation index significantly improved in both overlap syndrome and COPD patients, however these changes were significantly greater in the overlap syndrome than in the COPD group. Sleep architecture and autonomic dysfunction significantly improved in the overlap syndrome group but not in the COPD group. CPAP treatment was associated with an increased walking capacity from baseline from 226.4 +/- 95.3 m to 288.6 +/- 94.6 m (P < 0.05), and decreased urinary catecholamine levels, pre-exercise heart rate, oxygenation, and Borg scale in the overlap syndrome group. An improvement in the apnoea-hypopnoea index was an independent factor associated with the increase in walking distance (r = 0.564). CONCLUSION: Nocturnal CPAP may improve walking capacity in COPD patients with overlap syndrome.Trial registrationNCT00914264: http://www.clinicaltrials.gov/
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Algorithmic approach by endobronchial ultrasound-guided transbronchial needle aspiration for isolated intrathoracic lymphadenopathy: A study in a tuberculosis-endemic country.
J. Formos. Med. Assoc.
PUBLISHED: 01-24-2013
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Isolated intrathoracic lymphadenopathy (IT-LAP) is clinically challenging because of the difficult anatomic location and wide range of associated diseases, including tuberculosis (TB). Although sampling via endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for histopathology is a major development, there is still room for improvement. This study aimed to investigate an algorithmic approach driven by EBUS-TBNA and conventional bronchoscopy to streamline the management of IT-LAP.
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Role of flexible bronchoscopic cryotechnology in diagnosing endobronchial masses.
Ann. Thorac. Surg.
PUBLISHED: 01-24-2013
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Endobronchial masses obstruct the central airway, and cryotechnology is reportedly a feasible means of managing such masses. However, few reports have explored the role of cryotechnology in diagnosing endobronchial masses.
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Anti-Diabetic Activities of Jiaotaiwan in db/db Mice by Augmentation of AMPK Protein Activity and Upregulation of GLUT4 Expression.
Evid Based Complement Alternat Med
PUBLISHED: 01-16-2013
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Jiaotaiwan (JTW), which is composed of Coptis chinensis (CC) and cinnamon (CIN), is one of the most well-known traditional Chinese medicines. In this study, we investigated the antidiabetic effects and mechanism of JTW in db/db mice. Results showed that JTW significantly decreased the level of fasting blood glucose and improved glucose and insulin tolerance better than CC or CIN alone. JTW also effectively protected the pancreatic islet shape, augmented the activation of AMP-activated protein kinase (AMPK) in the liver, and increased the expression of glucose transporter 4 (GLUT4) protein in skeletal muscle and white fat. AMPK and GLUT4 contributed to glucose metabolism regulation and had an essential function in the development of diabetes mellitus (DM). Therefore, the mechanisms of JTW may be related to suppressing gluconeogenesis by activating AMPK in the liver and affecting glucose uptake in surrounding tissues through the upregulation of GLUT4 protein expression. These findings provided a new insight into the antidiabetic clinical applications of JTW and demonstrated the potential of JTW as a new drug candidate for DM treatment.
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SecA2 is not required for secretion of the surface autolysin IspC in Listeria monocytogenes serotype 4b.
J. Basic Microbiol.
PUBLISHED: 01-07-2013
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Listeria monocytogenes is one of several Gram-positive bacteria known to contain an auxiliary ATPase (SecA2) involved in the Sec secretion of a subset of proteins important to bacterial pathogenesis, including autolysins. It is not known if IspC, a novel surface-associated autolysin essential for full virulence of L. monocytogenes serotype 4b, is SecA2-dependent for secretion. By creating a secA2 gene deletion (?secA2) mutant from the wild type (WT) L. monocytogenes serotype 4b strain, in combination with the proteomic analysis of surface proteins and those secreted into the medium from both the mutant and the WT, we confirmed previous findings that two autolysins (p60 and NamA) are SecA2-dependent for secretion. However, this approach did not identify IspC as one of the surface proteins affected by the SecA2 deletion. Further experiments with immunofluorescence microscopy and Western blotting indicated that IspC was well displayed on the surface of both the ?secA2 mutant and WT cells, while p60 was not, clearly indicating that the secretion of IspC is not attributed to the SecA2 pathway. This finding sets IspC apart from other autolysins involved in virulence, such as p60 and NamA, in that SecA2 is not required for IspC secretion.
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NF-?B Repressing Factor Inhibits Chemokine Synthesis by Peripheral Blood Mononuclear Cells and Alveolar Macrophages in Active Pulmonary Tuberculosis.
PLoS ONE
PUBLISHED: 01-01-2013
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NF-?B repressing factor (NRF) is a transcriptional silencer implicated in the basal silencing of specific NF-?B targeting genes, including iNOS, IFN-? and IL-8/CXCL8. IP-10/CXCL10 and IL-8/CXCL8 are involved in neutrophil and lymphocyte recruitment against M. tuberculosis (MTb) and disease progression of pulmonary tuberculosis (TB). Alveolar macrophages (AM) and peripheral blood mononuclear cells (PBMC) were used to study the regulatory role of NRF in pulmonary TB. AM and PBMC were purified from 19 TB patients and 15 normal subjects. To study the underlying mechanism, PBMC were exposed to heated TB bacilli. The regulation role of NRF in IP-10/CXCL10 and IL-8/CXCL8 was determined by NRF knock-down or over-expression. NRF binding capabilities in promoter sites were measured by chromatin immunoprecipitation (ChIP) assay. The levels of IP-10/CXCL10, IL-8/CXCL8 and NRF were significantly higher in AM and PBMC in patients with active TB. NRF played an inhibitory role in IP-10/CXCL10 and IL-8/CXCL8 inductions. We delineate the role of NRF in pulmonary TB, which inhibits the expressions of IP-10/CXCL10 and IL-8/CXCL8 in AM and PBMC of patients with high bacterial load. NRF may serve as an endogenous repressor to prevent robust increase in IP-10/CXCL10 and IL-8/CXCL8 when TB bacterial load is high.
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Enhancement of cerenkov luminescence imaging by dual excitation of er(3+), yb(3+)-doped rare-Earth microparticles.
PLoS ONE
PUBLISHED: 01-01-2013
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Cerenkov luminescence imaging (CLI) has been successfully utilized in various fields of preclinical studies; however, CLI is challenging due to its weak luminescent intensity and insufficient penetration capability. Here, we report the design and synthesis of a type of rare-earth microparticles (REMPs), which can be dually excited by Cerenkov luminescence (CL) resulting from the decay of radionuclides to enhance CLI in terms of intensity and penetration. Methods: Yb(3+)- and Er(3+)- codoped hexagonal NaYF4 hollow microtubes were synthesized via a hydrothermal route. The phase, morphology, and emission spectrum were confirmed for these REMPs by power X-ray diffraction (XRD), scanning electron microscopy (SEM), and spectrophotometry, respectively. A commercial CCD camera equipped with a series of optical filters was employed to quantify the intensity and spectrum of CLI from radionuclides. The enhancement of penetration was investigated by imaging studies of nylon phantoms and nude mouse pseudotumor models. Results: the REMPs could be dually excited by CL at the wavelengths of 520 and 980 nm, and the emission peaks overlaid at 660 nm. This strategy approximately doubled the overall detectable intensity of CLI and extended its maximum penetration in nylon phantoms from 5 to 15 mm. The penetration study in living animals yielded similar results. Conclusions: this study demonstrated that CL can dually excite REMPs and that the overlaid emissions in the range of 660 nm could significantly enhance the penetration and intensity of CL. The proposed enhanced CLI strategy may have promising applications in the future.
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Generation and Analysis of a Large-Scale Expressed Sequence Tag Database from a Full-Length Enriched cDNA Library of Developing Leaves of Gossypium hirsutum L.
PLoS ONE
PUBLISHED: 01-01-2013
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Cotton (Gossypium hirsutum L.) is one of the worlds most economically-important crops. However, its entire genome has not been sequenced, and limited resources are available in GenBank for understanding the molecular mechanisms underlying leaf development and senescence.
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Evaluation of a novel thermosensitive heparin-poloxamer hydrogel for improving vascular anastomosis quality and safety in a rabbit model.
PLoS ONE
PUBLISHED: 01-01-2013
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Despite progress in the design of advanced surgical techniques, stenosis recurs in a large percentage of vascular anastomosis. In this study, a novel heparin-poloxamer (HP) hydrogel was designed and its effects for improving the quality and safety of vascular anastomosis were studied. HP copolymer was synthesized and its structure was confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy ((1)H-NMR). Hydrogels containing HP were prepared and their important characteristics related to the application in vascular anastomosis including gelation temperature, rheological behaviour and micromorphology were measured. Vascular anastomosis were performed on the right common carotid arteries of rabbits, and the in vivo efficiency and safety of HP hydrogel to achieve vascular anastomosis was verified and compared with Poloxamer 407 hydrogel and the conventional hand-sewn method using Doppler ultrasound, CT angiograms, scanning electron microscopy (SEM) and histological technique. Our results showed that HP copolymer displayed special gel-sol-gel phase transition behavior with increasing temperature from 5 to 60 °C. HP hydrogel prepared from 18 wt% HP solution had a porous sponge-like structure, with gelation temperature at approximately 38 °C and maximum elastic modulus at 10,000 Pa. In animal studies, imaging and histological examination of rabbit common jugular artery confirmed that HP hydrogel group had similar equivalent patency, flow and burst strength as Poloxamer 407 group. Moreover, HP hydrogel was superior to poloxamer 407 hydrogel and hand-sewn method for restoring the functions and epithelial structure of the broken vessel junctions after operation. By combining the advantages of heparin and poloxamer 407, HP hydrogel holds high promise for improving vascular anastomosis quality and safety.
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The role of RING box protein 1 in mouse oocyte meiotic maturation.
PLoS ONE
PUBLISHED: 01-01-2013
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RING box protein-1 (RBX1) is an essential component of Skp1-cullin-F-box protein (SCF) E3 ubiquitin ligase and participates in diverse cellular processes by targeting various substrates for degradation. However, the physiological function of RBX1 in mouse oocyte maturation remains unknown. Here, we examined the expression, localization and function of RBX1 during mouse oocyte meiotic maturation. Immunofluorescence analysis showed that RBX1 displayed dynamic distribution during the maturation process: it localized around and migrated along with the spindle and condensed chromosomes. Rbx1 knockdown with the appropriate siRNAs led to a decreased rate of first polar body extrusion and most oocytes were arrested at metaphase I. Moreover, downregulation of Rbx1 caused accumulation of Emi1, an inhibitor of the anaphase-promoting complex/cyclosome (APC/C), which is required for mouse meiotic maturation. In addition, we found apparently increased expression of the homologue disjunction-associated protein securin and cyclin B1, which are substrates of APC/C E3 ligase and need to be degraded for meiotic progression. These results indicate the essential role of the SCF(?TrCP)-EMI1-APC/C axis in mouse oocyte meiotic maturation. In conclusion, we provide evidence for the indispensable role of RBX1 in mouse oocyte meiotic maturation.
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Using acoustic cavitation to enhance chemotherapy of DOX liposomes: experiment in vitro and in vivo.
Drug Dev Ind Pharm
PUBLISHED: 12-21-2011
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Experiments in vitro and in vivo were designed to investigate tumor growth inhibition of chemotherapeutics-loaded liposomes enhanced by acoustic cavitation. Doxorubicin-loaded liposomes (DOX liposomes) were used in experiments to investigate acoustic cavitation mediated effects on cell viability and chemotherapeutic function. The influence of lingering sensitive period after acoustic cavitation on tumor inhibition was also investigated. Animal experiment was carried out to verify the practicability of this technique in vivo. From experiment results, blank phospholipid-based microbubbles (PBM) combined with ultrasound (US) at intensity below 0.3 W/cm² could produce acoustic cavitation which maintained cell viability at high level. Compared with DOX solution, DOX liposomes combined with acoustic cavitation exerted effective tumor inhibition in vitro and in vivo. The lingering sensitive period after acoustic cavitation could also enhance the susceptibility of tumor to chemotherapeutic drugs. DOX liposomes could also exert certain tumor inhibition under preliminary acoustic cavitation. Acoustic cavitation could enhance the absorption efficiency of DOX liposomes, which could be used to reduce DOX adverse effect on normal organs in clinical chemotherapy.
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Development and evaluation of a reverse dot blot assay for the simultaneous detection of common alpha and beta thalassemia in Chinese.
Blood Cells Mol. Dis.
PUBLISHED: 11-04-2011
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Thalassemia is the commonest inherited autosomal recessive disorders of hemoglobin in southern China. We developed and evaluated a reverse dot blot (RDB) assay combined with flow-through hybridization technology platform for the rapid and simultaneous identification of 5 types of ?-thalassemia and 16 types of ?-thalassemia common in Chinese. Reliable genotyping of wild-type and thalassemic genomic DNA samples was achieved by means of a gene chip on which allele-specific oligonucleotide probes were immobilized on a nylon membrane. This method involved two multiplex PCR amplification systems of ?-thalassemia and ?-thalassemia and one time of hybridization. The whole procedure starting from blood sampling to the identification of thalassemia genotype required less than 4h. The diagnostic reliability of this reverse dot blot assay was evaluated on 427 samples (387 cases of thalassemia and 40 healthy persons) by using direct DNA sequence analysis and gap-PCR in a blind study. These samples included 377 cases of blood, 7 cases of amniotic fluid, 18 cases of chorionic villus, and 25 cases of cord blood. The RDB gene chip was in complete concordance with the reference method. The reverse dot blot assay was a simple, rapid, accurate, and cost-effective method to identify common thalassemia genotypes in the Chinese population.
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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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