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Find video protocols related to scientific articles indexed in Pubmed.
Rectangular Ion Funnel (RIF): A New Ion Funnel Interface for Structures for Lossless Ion Manipulations (SLIM).
Anal. Chem.
PUBLISHED: 11-20-2014
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Structures for Lossless Ion Manipulations (SLIM) have recently demonstrated the ability for near lossless ion focusing, transfer, and trapping in sub-atmospheric pressure regions. While lossless ion manipulations are advantageously applied to the applications of ion mobility separations and gas phase reactions, ion introduction through ring electrode ion funnels or more conventional ion optics to SLIM can involve discontinuities in electric fields or other perturbations that result in ion losses. In this work, we developed and investigated a new funnel design that aims to seamlessly couple to SLIM at the funnel exit. This rectangular ion funnel (RIF) was initially evaluated by ion simulations, fabricated utilizing printed circuit board technology and tested experimentally. The RIF was integrated to a SLIM-TOF MS system, and the operating parameters, including RF, DC bias of the RIF electrodes, and electric fields for effectively interfacing with a SLIM were characterized. The RIF provided a 2-fold sensitivity increase without significant discrimination over a wide m/z range along with greatly improved SLIM operational stability.
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All-optical self-referencing measurement of vectorial optical arbitrary waveform.
Opt Express
PUBLISHED: 11-18-2014
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We propose the Vectorial E-field Characterization Through all-Optical and self-Referenced (VECTOR) method to characterize vectorial optical arbitrary waveform with up to 100% duty cycle, which is free of ambiguity, iteration, radio-frequency or external optical reference, restriction on repetition rate, and requirement of external interferometric stabilization. The feasibility of VECTOR is experimentally verified by different waveforms created by a phase-modulated CW comb source and a built-in polarization line-by-line pulse shaper.
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Cadherin controls nectin recruitment into adherens junctions by remodeling the actin cytoskeleton.
J. Cell. Sci.
PUBLISHED: 11-15-2014
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The mechanism that coordinates different adhesion receptors is poorly understood. We investigated this mechanism by focusing on the nectin-2 and E-cadherin adherens junction receptors. Cadherin is not required for the basic process of nectin junction formation since nectin-2 forms junctions in cadherin-deficient A431D cells. Formation of nectin junctions in these cells, however, becomes regulated by cadherin as soon as E-cadherin is reconstituted. E-cadherin recruits nectin-2 into adherens junctions, where both proteins form distinct but tightly associated clusters. Live-cell imaging showed that the appearance of cadherin clusters often precedes that of nectin clusters at sites of junction assembly. Inactivation of cadherin clustering by different strategies concomitantly suppresses the formation of nectin clusters. Furthermore, cadherin significantly increases the stability of nectin clusters, thereby making them resistant to the BC-12 antibody, which targets the nectin-2 adhesion interface. By testing different cadherin-?-catenin chimeras, we showed that the recruitment of nectin into chimera junctions is mediated by the actin-binding domain of ?-catenin. Our data suggests that cadherin regulates-assembly of nectin junctions through ?-catenin-induced remodeling of the actin cytoskeleton around the cadherin clusters.
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Establishment of a New Ovarian Cancer Cell Line CA5171.
Reprod Sci
PUBLISHED: 11-15-2014
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A new cell line, CA5171, derived from a chemotherapy-naive, high-grade undifferentiated ovarian carcinoma was established and characterized. The CA5171 cells presented with cobblestone morphology and a doubling time of 24 hours. Gene mutation analysis showed that the cells belonged to the type II ovarian cancer pathway with mutations of PIK3CA, PTEN, and TP53. Single-nucleotide polymorphism array analysis showed no homozygous gene deletion; however, several loci of gene copy number gains were noted in chromosome 1, 2, 5, 9, 10, 12, 15, 16, 20, and X. The in vitro and in vivo experiments showed that the cells were sensitive to paclitaxel and doxorubicin, but resistant to cisplatin. The cells also presented epithelial-mesenchymal transition properties that may have been related to their invasion and migration potential. The CA5171 cells show the potential as a new cell line for studies on epithelial ovarian carcinoma.
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Younger pubertal age is associated with allergy and other atopic conditions in girls.
Pediatr Allergy Immunol
PUBLISHED: 11-13-2014
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Early menarche is linked to higher incidence of adult asthma suggesting that earlier puberty may influence type 2 immune responses characteristic of allergic diseases. We examined the hypothesis that timing of breast and pubic hair development, which precede menarche, are associated with increased childhood atopic conditions.
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Benzene absorption in a protuberant-grid-type zinc(ii)-organic framework triggered by the migration of guest water molecules.
Dalton Trans
PUBLISHED: 11-12-2014
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The 2D protuberant-grid-type Zn(ii)-organic framework consists of unusual racemic interdigitated bilayers and comprises a 3D intersecting channel system. The framework is thermally stable and the channels contain multiple water aggregates. Accompanying the migration of guest water molecules, only the specific channels in the bilayers along the b axis can easily and efficiently absorb guest benzene molecules in a regular manner.
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Parity, lactation, and breast cancer subtypes in African American women: results from the AMBER Consortium.
J. Natl. Cancer Inst.
PUBLISHED: 10-01-2014
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African American (AA) women have a disproportionately high incidence of estrogen receptor-negative (ER-) breast cancer, a subtype with a largely unexplained etiology. Because childbearing patterns also differ by race/ethnicity, with higher parity and a lower prevalence of lactation in AA women, we investigated the relation of parity and lactation to risk of specific breast cancer subtypes.
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Intake of energy-dense foods, fast foods, sugary drinks, and breast cancer risk in african american and European american women.
Nutr Cancer
PUBLISHED: 09-29-2014
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Limiting energy-dense foods, fast foods, and sugary drinks that promote weight gain is a cancer prevention recommendation, but no studies have evaluated intake in relation to breast cancer risk in African American (AA) women. In a case-control study with 1692 AA women (803 cases and 889 controls) and 1456 European American (EA) women (755 cases and 701 controls), odds ratios (OR) and 95% confidence intervals (CI) for risk were computed, stratifying for menopausal and estrogen receptor (ER) status. Among postmenopausal EA women, breast cancer risk was associated with frequent consumption of energy-dense foods (OR = 2.95; 95% CI: 1.66-5.22), fast foods (OR = 2.35; 95% CI: 1.38-4.00), and sugary drinks (OR = 2.05; 95% CI: 1.13-3.70). Elevated risk of ER+ tumors in EA women was associated with energy-dense (OR = 1.75; 95% CI: 1.14-2.69) and fast foods (OR = 1.84; 95% CI: 1.22-2.77). Among AA women, frequent fast food consumption was related to premenopausal breast cancer risk (OR = 1.97; 95% CI: 1.13-3.43), and with ER+ tumors. Energy adjustment attenuated risk estimates in AA women, while strengthening them among EA women. Frequent consumption of energy-dense and fast foods that have poor nutritive value appeared to increase breast cancer risk in AA and EA women, with differences by menopausal status and ER status.
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Mobility-resolved ion selection in uniform drift field ion mobility spectrometry/mass spectrometry: dynamic switching in structures for lossless ion manipulations.
Anal. Chem.
PUBLISHED: 09-26-2014
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A Structures for Lossless Ion Manipulations (SLIM) module that allows ion mobility separations and the switching of ions between alternative drift paths is described. The SLIM switch component has a "Tee" configuration and allows the efficient switching of ions between a linear path and a 90-degree bend. By controlling switching times, ions can be efficiently directed to an alternative channel as a function of their mobilities. In the initial evaluation the switch is used in a static mode and shown compatible with high performance ion mobility separations at 4 Torr. In the dynamic mode, we show that mobility-selected ions can be switched into the alternative channel, and that various ion species can be independently selected based on their mobilities for time-of-flight mass spectrometer (TOF MS) IMS detection and mass analysis. This development also provides the basis of, for example, the selection of specific mobilities for storage and accumulation, and the key component of modules for the assembly of SLIM devices enabling much more complex sequences of ion manipulations.
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Variants of estrogen-related genes and breast cancer risk in European and African American women.
Endocr. Relat. Cancer
PUBLISHED: 09-16-2014
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It has been observed previously that compared with women of European ancestry (EA), those of African ancestry (AA) are more likely to develop estrogen receptor (ER)-negative breast cancer, although the mechanisms have not been elucidated. We tested the associations between breast cancer risk and a targeted set of 20 genes known to be involved in estrogen synthesis, metabolism, and response and potential gene-environment interactions using data and samples from 1307 EA (658 cases) and 1365 AA (621 cases) participants from the Women's Circle of Health Study (WCHS). Multivariable logistic regression found evidence of associations with single-nucleotide polymorphisms (SNPs) in the ESR1 gene in EA women (rs1801132, odds ratio (OR)=1.47, 95% CI=1.20-1.80, P=0.0002; rs2046210, OR=1.24, 95% CI=1.04-1.47, P=0.02; and rs3020314, OR=1.43, 95% CI=1.19-1.70, P=0.00009), but not in AA women. The only other gene associated with breast cancer risk was CYP1A2 in AA women (rs2470893, OR=1.42, 95% CI=1.00-2.02, P=0.05), but not in EA women. When stratified by ER status, ESR1 rs1801132, rs2046210, and rs3020314 showed stronger associations in ER-positive than in ER-negative breast cancer in only EA women. Associations with the ESR1 SNPs in EA women also appeared to be stronger with longer endogenous estrogen exposure or hormonal replacement therapy use. Our results indicate that there may be differential genetic influences on breast cancer risk in EA compared with AA women and that these differences may be modified by tumor subtype and estrogen exposures. Future studies with a larger sample size may determine the full contribution of estrogen-related genes to racial/ethnic differences in breast cancer.
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Experimental evaluation and optimization of structures for lossless ion manipulations for ion mobility spectrometry with time-of-flight mass spectrometry.
Anal. Chem.
PUBLISHED: 09-05-2014
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We report on the performance of structures for lossless ion manipulation (SLIM) as a means for transmitting ions and performing ion mobility separations (IMS). Ions were successfully transferred from an electrospray ionization (ESI) source to the TOF MS analyzer by means of a linear SLIM, demonstrating lossless ion transmission and an alternative arrangement including a 90° turn. First, the linear geometry was optimized for radial confinement by tuning RF on the central "rung" electrodes and potentials on the DC-only guard electrodes. Selecting an appropriate DC guard bias (2-6 V) and RF amplitude (?160 V(p-p) at 750 kHz) resulted in the greatest ion intensities. Close to ideal IMS resolving power was maintained over a significant range of applied voltages. Second, the 90° turn was optimized for radial confinement by tuning RF on the rung electrodes and DC on the guard electrodes. However, both resolving power and ion transmission showed a dependence on these voltages, and the best conditions for both were >300 V(p-p) RF (685 kHz) and 7-11 V guard DC bias. Both geometries provide IMS resolving powers at the theoretical limit (R ~ 58), showing that degraded resolution from a "racetrack" effect from turning around a corner can be successfully avoided, and the capability also was maintained for essentially lossless ion transmission.
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Potential therapeutic roles of tanshinone IIA in human bladder cancer cells.
Int J Mol Sci
PUBLISHED: 09-04-2014
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Tanshinone IIA (Tan-IIA), one of the major lipophilic components isolated from the root of Salviae Miltiorrhizae, has been found to exhibit anticancer activity in various cancer cells. We have demonstrated that Tan-IIA induces apoptosis in several human cancer cells through caspase- and mitochondria-dependent pathways. Here we explored the anticancer effect of Tan-IIA in human bladder cancer cell lines. Our results showed that Tan-IIA caused bladder cancer cell death in a time- and dose-dependent manner. Tan-IIA induced apoptosis through the mitochondria-dependent pathway in these bladder cancer cells. Tan-IIA also suppressed the migration of bladder cancer cells as revealed by the wound healing and transwell assays. Finally, combination therapy of Tan-IIA with a lower dose of cisplatin successfully killed bladder cancer cells, suggesting that Tan-IIA can serve as a potential anti-cancer agent in bladder cancer.
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Structural perspectives of an engineered ?-1,4-xylanase with enhanced thermostability.
J. Biotechnol.
PUBLISHED: 09-03-2014
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The glycoside hydrolase 10 (GH10) xylanase from Streptomyces sp. 9 (XynAS9) can operate in a broad range of pH and temperature, and thus is a potential candidate for commercial applications. Recently, we engineered XynAS9 via mutating several residues in accordance with the consensus sequences of GH10 thermophilic xylanases in an attempt to improve the enzyme thermostability and thermotolerance. The most promising effects were observed in the double mutant V81P/G82E. In order to investigate the molecular mechanism of the improved thermal profile of XynAS9, complex crystal structures of the wild type (WT) and mutant (MT) enzyme were solved at 1.88-2.05? resolution. The structures reveal a classical GH10 (?/?)8 TIM-barrel fold. In MT XynAS9, E82 forms several interactions to its neighboring residues, which might aid in stabilizing the local structure. Furthermore, the MT structure showed lower B factors for individual residues compared to the WT structure, reflecting the increased MT protein rigidity. Analyses of the XynAS9 structures also delineate the detailed enzyme-substrate interaction network. More importantly, possible explanations for the enhanced thermal profiles of MT XynAS9 are proposed, which may be a useful strategy for enzyme engineering in the future.
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Design of Portable Mass Spectrometers with Handheld Probes: Aspects of the Sampling and Miniature Pumping Systems.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 08-26-2014
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Miniature mass spectrometry analytical systems of backpack configuration fitted with sampling probes could potentially be of significant interest for in-field, real-time chemical analysis. In this study, various configurations were explored in which a long narrow tube was used to connect the turbo and backing pumps used to create and maintain vacuum. Also, for the first time we introduced two new types of pumps for miniature mass spectrometers, the Creare 130 g drag pump and Creare 350 g scroll backing pump. These pumps, along with another Creare 550 turbo pump and the commercially available Pfeiffer HiPace 10 turbo and KnF diaphragm backing pumps, were tested with the backpack configurations. The system performance, especially the scan time, was characterized when used with a discontinuous atmospheric pressure interface (DAPI) for ion introduction. The pumping performance in the pressure region above 1 mtorr is critical for DAPI operation. The 550 g turbo pump was shown to have a relatively higher pumping speed above 1 mtorr and gave a scan time of 300 ms, almost half the value obtained with the larger, heavier HiPace 10 often used with miniature mass spectrometers. The 350 g scroll pump was also found to be an improvement over the diaphragm pumps generally used as backing pumps. With a coaxial low temperature plasma ion source, direct analysis of low volatility compounds glass slides was demonstrated, including 1 ng DNP (2,4-Dinitrophenol) and 10 ng TNT (2,4,6-trinitrotoluene) with Creare 550 g turbo pump as well as 10 ng cocaine and 20 ng DNP with Creare 130 g drag pump.
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Anabolic androgens affect the competitive interactions in cell migration and adhesion between normal mouse urothelial cells and urothelial carcinoma cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-23-2014
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The urothelium is constantly rebuilt by normal urothelial cells to regenerate damaged tissues caused by stimuli in urine. However, the urothelial carcinoma cells expand the territory by aberrant growth of tumor cells, which migrate and occupy the damaged tissues to spread outside and disrupt the normal cells and organized tissues and form a tumor. Therefore, the interaction between normal urothelial cells and urothelial carcinoma cells affect the initiation and progression of urothelial tumors if normal urothelial cells fail to migrate and adhere to the damages sites to regenerate the tissues. Here, comparing normal murine urothelial cells with murine urothelial carcinoma cells (MBT-2), we found that normal cells had less migration ability than carcinoma cells. And in our co-culture system we found that carcinoma cells had propensity migrating toward normal urothelial cells and carcinoma cells had more advantages to adhere than normal cells. To reverse this condition, we used anabolic androgen, dihyrotestosterone (DHT) to treat normal cells and found that DHT treatment increased the migration ability of normal urothelial cells toward carcinoma cells and the adhesion capacity in competition with carcinoma cells. This study provides the base of a novel therapeutic approach by using anabolic hormone-enforced normal urothelial cells to regenerate the damage urothelium and defend against the occupancy of carcinoma cells to thwart cancer development and recurrence.
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A prospective study of gynecological cancer risk in relation to adiposity factors: cumulative incidence and association with plasma adipokine levels.
PLoS ONE
PUBLISHED: 08-12-2014
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Associations of obesity and obesity-related metabolic factors (adiposity factors) with uterine corpus cancer (UCC) and ovarian cancer (OVC) risk have been described. Still, a cause-effect relationship and the underlying mediators remain unclear, particularly for low-incidence populations. We aimed to prospectively determine whether adiposity factors could predict the development of UCC and OVC in Taiwanese women. To explore the biological mediators linking adiposity factors to cancer risk, we examined the association of two adipokines, leptin and adiponectin, with the gynecological cancers.
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A linearity-enhanced time-domain CMOS thermostat with process-variation calibration.
Sensors (Basel)
PUBLISHED: 07-13-2014
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This study proposes a linearity-enhanced time-domain complementary metal-oxide semiconductor (CMOS) thermostat with process-variation calibration for improving the accuracy, expanding the operating temperature range, and reducing test costs. For sensing temperatures in the time domain, the large characteristic curve of a CMOS inverter markedly affects the accuracy, particularly when the operating temperature range is increased. To enhance the on-chip linearity, this study proposes a novel temperature-sensing cell comprising a simple buffer and a buffer with a thermal-compensation circuit to achieve a linearised delay. Thus, a linearity-enhanced oscillator consisting of these cells can generate an oscillation period with high linearity. To achieve one-point calibration support, an adjustable-gain time stretcher and calibration circuit were adopted for the process-variation calibration. The programmable temperature set point was determined using a reference clock and a second (identical) adjustable-gain time stretcher. A delay-time comparator with a built-in customised hysteresis circuit was used to perform a time comparison to obtain an appropriate response. Based on the proposed design, a thermostat with a small area of 0.067 mm2 was fabricated using a TSMC 0.35-?m 2P4M CMOS process, and a robust resolution of 0.05 °C and dissipation of 25 ?W were achieved at a sample rate of 10 samples/s. An inaccuracy of -0.35 °C to 1.35 °C was achieved after one-point calibration at temperatures ranging from -40 °C to 120 °C. Compared with existing thermostats, the proposed thermostat substantially improves the circuit area, accuracy, operating temperature range, and test costs.
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Curvature-correction-based time-domain CMOS smart temperature sensor with an inaccuracy of -0.8?°C-1.2?°C after one-point calibration from -40?°C to 120?°C.
Rev Sci Instrum
PUBLISHED: 07-03-2014
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This paper proposes a time-domain CMOS smart temperature sensor featuring on-chip curvature correction and one-point calibration support for thermal management systems. Time-domain inverter-based temperature sensors, which exhibit the advantages of low power and low cost, have been proposed for on-chip thermal monitoring. However, the curvature is large for the thermal transfer curve, which substantially affects the accuracy as the temperature range increases. Another problem is that the inverter is sensitive to process variations, resulting in difficulty for the sensors to achieve an acceptable accuracy for one-point calibration. To overcome these two problems, a temperature-dependent oscillator with curvature correction is proposed to increase the linearity of the oscillatory width, thereby resolving the drawback caused by a costly off-chip second-order master curve fitting. For one-point calibration support, an adjustable-gain time amplifier was adopted to eliminate the effect of process variations, with the assistance of a calibration circuit. The proposed circuit occupied a small area of 0.073 mm(2) and was fabricated in a TSMC CMOS 0.35-?m 2P4M digital process. The linearization of the oscillator and the effect cancellation of process variations enabled the sensor, which featured a fixed resolution of 0.049?°C/LSB, to achieve an optimal inaccuracy of -0.8?°C to 1.2?°C after one-point calibration of 12 test chips from -40?°C to 120?°C. The power consumption was 35 ?W at a sample rate of 10 samples/s.
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Microgrooved Surface Modulates Neuron Differentiation in Human Embryonic Stem Cells.
Methods Mol. Biol.
PUBLISHED: 05-27-2014
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Stem cell-based therapies have drawn intensive attention in the neuronal regenerative fields. Several studies have revealed that stem cells can serve as an inexhaustible source for neurons for transplantation therapies. However, generation of neurons and directionality has not yet been fully investigated. Herein, we investigate the mechanical ramifications of surface topography on human embryonic cell differentiation. Microgrooved surfaces with various pitches were applied to modulate the neuron differentiation. Our protocol showed that neuron differentiation increased as grove pitch decreased. The results indicated that 2 ?m microgrooves can improve neuron growth by ~1.7-fold. Our results indicate the importance of mechanotransduction on neuronal differentiation and highlight the feasibility of manipulating the neuronal differentiation with surface topography, providing new perspectives for accommodating clinical transplantation.
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Nicotine alters mucin rheological properties.
Am. J. Physiol. Lung Cell Mol. Physiol.
PUBLISHED: 05-16-2014
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Tobacco smoke exposure, the major cause of chronic obstructive pulmonary disease (COPD), instigates a dysfunctional clearance of thick obstructive mucus. However, the mechanism underlying the formation of abnormally viscous mucus remains elusive. We investigated whether nicotine can directly alter the rheological properties of mucin by examining its physicochemical interactions with human airway mucin gels secreted from A549 lung epithelial cells. Swelling kinetics and multiple particle tracking were utilized to assess mucin gel viscosity change when exposed to nicotine. Herein we show that nicotine (?50 nM) significantly hindered postexocytotic swelling and hydration of released mucins, leading to higher viscosity, possibly by electrostatic and hydrophobic interactions. Moreover, the close association of nicotine and mucins allows airway mucus to function as a reservoir for prolonged nicotine release, leading to correlated pathogenic effects. Our results provide a novel explanation for the maltransport of poorly hydrated mucus in smokers. More importantly, this study further indicates that even low-concentration nicotine can profoundly increase mucus viscosity and thus highlights the health risks of secondhand smoke exposure.
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Crystal structures of ligand-bound octaprenyl pyrophosphate synthase from Escherichia coli reveal the catalytic and chain-length determining mechanisms.
Proteins
PUBLISHED: 05-12-2014
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Octaprenyl pyrophosphate synthase (OPPs) catalyzes consecutive condensation reactions of one allylic substrate farnesyl pyrophosphate (FPP) and five homoallylic substrate isopentenyl pyrophosphate (IPP) molecules to form a C40 long-chain product OPP, which serves as a side chain of ubiquinone and menaquinone. OPPs belongs to the trans-prenyltransferase class of proteins. The structures of OPPs from Escherichia coli were solved in the apo-form as well as in complexes with IPP and a FPP thio-analog, FsPP, at resolutions of 2.2-2.6 Å, and revealed the detailed interactions between the ligands and enzyme. At the bottom of the active-site tunnel, M123 and M135 act in concert to form a wall which determines the final chain length. These results represent the first ligand-bound crystal structures of a long-chain trans-prenyltransferase and provide new information on the mechanisms of catalysis and product chain elongation. Proteins 2014. © 2014 Wiley Periodicals, Inc.
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Screening frequency and atypical cells and the prediction of cervical cancer risk.
Obstet Gynecol
PUBLISHED: 05-03-2014
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To evaluate the screening efficacy and importance of atypical squamous cells and atypical glandular cells in predicting subsequent cervical cancer risk.
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Squalene synthase as a target for Chagas disease therapeutics.
PLoS Pathog.
PUBLISHED: 05-01-2014
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Trypanosomatid parasites are the causative agents of many neglected tropical diseases and there is currently considerable interest in targeting endogenous sterol biosynthesis in these organisms as a route to the development of novel anti-infective drugs. Here, we report the first x-ray crystallographic structures of the enzyme squalene synthase (SQS) from a trypanosomatid parasite, Trypanosoma cruzi, the causative agent of Chagas disease. We obtained five structures of T. cruzi SQS and eight structures of human SQS with four classes of inhibitors: the substrate-analog S-thiolo-farnesyl diphosphate, the quinuclidines E5700 and ER119884, several lipophilic bisphosphonates, and the thiocyanate WC-9, with the structures of the two very potent quinuclidines suggesting strategies for selective inhibitor development. We also show that the lipophilic bisphosphonates have low nM activity against T. cruzi and inhibit endogenous sterol biosynthesis and that E5700 acts synergistically with the azole drug, posaconazole. The determination of the structures of trypanosomatid and human SQS enzymes with a diverse set of inhibitors active in cells provides insights into SQS inhibition, of interest in the context of the development of drugs against Chagas disease.
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Associations between estrogen receptor-negative breast cancer and timing of reproductive events differ between African American and European American women.
Cancer Epidemiol. Biomarkers Prev.
PUBLISHED: 04-09-2014
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The effects of reproductive factors on breast cancer risk seem to differ by estrogen receptor (ER) status. Menarche and first live birth (FLB) tend to occur at younger ages in African Americans (AA) than European Americans (EA), and could play a role in breast cancer disparities. In the Women's Circle of Health Study, a case-control study of breast cancer in EA and AA women, in-person interviews were conducted to collect epidemiologic data, including reproductive histories. Data on ER status, abstracted from pathology reports, were available for 814 AA and 538 EA breast cancer cases, and were analyzed with 1015 AA and 715 EA controls, to evaluate associations between subgroups and age at menarche, age at FLB, and the interval between those ages. Among AA women, later age at menarche (?14 years) was associated with reduced risk of both ER(+) and ER(-) breast cancer, with ORs strongest for ER(-) disease [OR = 0.57; 95% confidence interval (CI), 0.37-0.88]; associations were weaker and nonsignificant for EA women. There were no significant associations with age at FLB, but AA women with a FLB within 15 years of menarche had increased risk of ER(-) disease (OR = 2.26; 95% CI, 1.29-3.95), with no significant associations among EAs. In our data, earlier age at menarche and shorter intervals until FLB are associated with ER(-) breast cancer in AA women; differential distributions by race of these and other reproductive risk factors could contribute to the higher prevalence of ER(-) breast cancer in AA women. Cancer Epidemiol Biomarkers Prev; 23(6); 1115-20. ©2014 AACR.
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Structure, function and inhibition of ent-kaurene synthase from Bradyrhizobium japonicum.
Sci Rep
PUBLISHED: 04-03-2014
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We report the first X-ray crystal structure of ent-kaur-16-ene synthase from Bradyrhizobium japonicum, together with the results of a site-directed mutagenesis investigation into catalytic activity. The structure is very similar to that of the ? domains of modern plant terpene cyclases, a result that is of interest since it has been proposed that many plant terpene cyclases may have arisen from bacterial diterpene cyclases. The ent-copalyl diphosphate substrate binds to a hydrophobic pocket near a cluster of Asp and Arg residues that are essential for catalysis, with the carbocations formed on ionization being protected by Leu, Tyr and Phe residues. A bisphosphonate inhibitor binds to the same site. In the kaurene synthase from the moss Physcomitrella patens, 16-?-hydroxy-ent-kaurane as well as kaurene are produced since Leu and Tyr in the P. patens kaurene synthase active site are replaced by smaller residues enabling carbocation quenching by water. Overall, the results represent the first structure determination of a bacterial diterpene cyclase, providing insights into catalytic activity, as well as structural comparisons with diverse terpene synthases and cyclases which clearly separate the terpene cyclases from other terpene synthases having highly ?-helical structures.
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Self-referenced frequency comb measurement by using a polarization line-by-line pulse shaper.
Opt Lett
PUBLISHED: 04-02-2014
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A polarization line-by-line pulse shaper is used for generation and noniterative spectral phase retrieval of optical arbitrary waveforms (OAWs) spanning over the entire repetition period. The method is completely reference-free, making it particularly attractive in measuring high repetition-rate OAW.
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Dual protection therapy with staged coronary artery bypass surgery and stenting in patients with left main coronary artery stenosis: long-term results from a single center.
Heart Surg Forum
PUBLISHED: 03-18-2014
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We evaluated the efficacy and safety of dual protection therapy with staged coronary artery bypass grafting (CABG) and bare-metal stenting (BMS) in patients with left main coronary artery (LMCA) disease.
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The evolution and investigation of native coronary arteries in patients after coronary stent implantation: a study by 320-detector CT angiography.
Int J Cardiovasc Imaging
PUBLISHED: 03-13-2014
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To study the role of 320-detector coronary computed tomography angiography (CTA) in assessing native coronary arteries in patients treated with coronary stents. 123 patients with coronary stenting received both CTA and conventional coronary angiography (CCA) within 1 day. The clinical parameters, coronary calcium scoring, CTA and CCA were analyzed to determine the prevalence of significant stenosis of native coronary arteries (SSNCA), the predictive value of CTA and the factors correlating with SSNCA and newly developed SSNCA after stenting (NDSSNCAS), with CCA as the standard of reference, using both vessel-based analysis (VBA) and patient-based analysis (PBA). Both the source and the reconstructed images were analyzed by CTA. All native coronary arteries were interpretable independent of cardiac motion. CTA showed a sensitivity/specificity of 93.5%/97.3% and 92.5%/92.5% in diagnosing SSNCA in VBA and PBA, respectively. The significant factors related to SSNCA were higher calcium scores (P = 0.003), a higher serum glucose level (P = 0.048), a greater number of vessels without previous stent placement (P = 0.003) and fewer stents implanted within the vessels (P = 0.003). The risk factors showed no significant correlation from PBA on SSNCA or from NDSSNCAS on either VBA or PBA. CTA demonstrates excellent correlation with CCA. The prevalence of SSNCA is significantly correlated with the presence of higher calcium scores in the arteries, a higher serum glucose level, a greater number of vessels without previous stent placement and fewer stents implanted within the vessels; PBA on SSNCA and NDSSNCAS on both VBA and PBA showed no significance.
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Structural analysis of a glycoside hydrolase family 11 xylanase from Neocallimastix patriciarum: insights into the molecular basis of a thermophilic enzyme.
J. Biol. Chem.
PUBLISHED: 03-11-2014
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The catalytic domain of XynCDBFV, a glycoside hydrolase family 11 (GH11) xylanase from ruminal fungus Neocallimastix patriciarum previously engineered to exhibit higher specific activity and broader pH adaptability, holds great potential in commercial applications. Here, the crystal structures of XynCDBFV and its complex with substrate were determined to 1.27-1.43 ? resolution. These structures revealed a typical GH11 ?-jelly-roll fold and detailed interaction networks between the enzyme and ligands. Notably, an extended N-terminal region (NTR) consisting of 11 amino acids was identified in the XynCDBFV structure, which is found unique among GH11 xylanases. The NTR is attached to the catalytic core by hydrogen bonds and stacking forces along with a disulfide bond between Cys-4 and Cys-172. Interestingly, the NTR deletion mutant retained 61.5% and 19.5% enzymatic activity at 55 °C and 75 °C, respectively, compared with the wild-type enzyme, whereas the C4A/C172A mutant showed 86.8% and 23.3% activity. These results suggest that NTR plays a role in XynCDBFV thermostability, and the Cys-4/Cys-172 disulfide bond is critical to the NTR-mediated interactions. Furthermore, we also demonstrated that Pichia pastoris produces XynCDBFV with higher catalytic activity at higher temperature than Escherichia coli, in which incorrect NTR folding and inefficient disulfide bond formation might have occurred. In conclusion, these structural and functional analyses of the industrially favored XynCDBFV provide a molecular basis of NTR contribution to its thermostability.
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Arsenic Trioxide Inhibits CXCR4-Mediated Metastasis by Interfering miR-520h/PP2A/NF-?B Signaling in Cervical Cancer.
Ann. Surg. Oncol.
PUBLISHED: 03-05-2014
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Arsenic apparently affects numerous intracellular signal transduction pathways and causes many alterations leading to apoptosis and differentiation in malignant cells. We and others have demonstrated that arsenic inhibits the metastatic capacity of cancer cells. Here we present additional mechanistic studies to elucidate the potential of arsenic as a promising therapeutic inhibitor of metastasis.
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Preliminary X-ray diffraction analysis of a thermophilic ?-1,3-1,4-glucanase from Clostridium thermocellum.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 02-26-2014
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?-1,3-1,4-Glucanases catalyze the specific hydrolysis of internal ?-1,4-glycosidic bonds adjacent to the 3-O-substituted glucose residues in mixed-linked ?-glucans. The thermophilic glycoside hydrolase CtGlu16A from Clostridium thermocellum exhibits superior thermal profiles, high specific activity and broad pH adaptability. Here, the catalytic domain of CtGlu16A was expressed in Escherichia coli, purified and crystallized in the trigonal space group P3121, with unit-cell parameters a=b=74.5, c=182.9?Å, by the sitting-drop vapour-diffusion method and diffracted to 1.95?Å resolution. The crystal contains two protein molecules in an asymmetric unit. Further structural determination and refinement are in progress.
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Molecular alterations in endometrial and ovarian clear cell carcinomas: clinical impacts of telomerase reverse transcriptase promoter mutation.
Mod. Pathol.
PUBLISHED: 02-24-2014
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Recently, mutations of telomerase reverse transcriptase (TERT) promoter were found in several types of cancer. A few reports demonstrate TERT promoter mutations in ovarian clear cell carcinomas but endometrial clear cell carcinoma has not been studied. The aims of this study were to compare differences of molecular alterations and clinical factors, and identify their prognostic impact in endometrial and ovarian clear cell carcinomas. We evaluated mutations of the TERT promoter and PIK3CA, expression of ARID1A, and other clinicopathological factors in 56 ovarian and 14 endometrial clear cell carcinomas. We found that TERT promoter mutations were present in 21% (3/14) of endometrial clear cell carcinomas and 16% (9/56) of ovarian clear cell carcinomas. Compared with ovarian clear cell carcinomas, endometrial clear cell carcinomas showed older mean patient age (P<0.001), preserved ARID1A immunoreactivity (P=0.017) and infrequent PIK3CA mutation (P=0.025). In ovarian clear cell carcinomas, TERT promoter mutations were correlated with patient age >45 (P=0.045) and preserved ARID1A expression (P=0.003). In cases of endometrial clear cell carcinoma, TERT promoter mutations were not statistically associated with any other clinicopathological factors. In ovarian clear cell carcinoma patients with early FIGO stage (stages I and II), TERT promoter mutation was an independent prognostic factor and correlated with a shorter disease-free survival and overall survival (P=0.015 and 0.009, respectively). In recurrent ovarian clear cell carcinoma patients with early FIGO stage, TERT promoter mutations were associated with early relapse within 6 months (P=0.018). We concluded that TERT promoter mutations were present in endometrial and ovarian clear cell carcinomas. Distinct molecular alteration patterns in endometrial and ovarian clear cell carcinomas implied different processes of tumorigenesis in these morphologically similar tumors. In ovarian clear cell carcinoma of early FIGO stage, patients with TERT promoter mutation require close follow-up during the initial 6 months following chemotherapy.Modern Pathology advance online publication, 1 August 2014; doi:10.1038/modpathol.2014.93.
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Autonomous in situ analysis and real-time chemical detection using a backpack miniature mass spectrometer: concept, instrumentation development, and performance.
Anal. Chem.
PUBLISHED: 02-24-2014
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A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1-2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.
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Mini 12, miniature mass spectrometer for clinical and other applications--introduction and characterization.
Anal. Chem.
PUBLISHED: 02-24-2014
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A benchtop miniature mass spectrometer system, Mini 12, with ambient ionization source and tandem mass spectrometry capabilities has been developed and characterized. This instrument was developed as a self-contained system to produce quantitative results for unprocessed samples of small volumes including nonvolatile analytes. The ion processing system, vacuum system, and control system are detailed. An integrated sample loading system facilitates automated operation. A user interface has been developed to acquire and to interpret analytical results for personnel who have limited mass spectrometry knowledge. Peak widths of ?m/z 0.6 Th (full width at half-maximum) and a mass range of up to m/z 900 are demonstrated with the rectilinear ion trap mass analyzer. Multistage experiments up to MS(5) are accomplished. Consumable cartridges have been designed for use in ambient paper spray ionization, and the recently developed extraction spray ionization method has been employed to improve the quantitative performance. Monitoring of trace-levels of chemicals in therapeutic drugs, as well as in food safety and environmental protection operations is demonstrated. Dual MS/MS scans are implemented to obtain the intensities of the fragment ions from the analyte and its internal standard, and the ratio is used in quantitative analysis of complex samples. Limits of quantitation (LOQ) of 7.5 ng/mL, with relative standard deviations below 10%, have been obtained for selected therapeutic drugs in whole blood throughout their individual therapeutic ranges.
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Solitary primary peritoneal carcinoma arising from the omentum.
Taiwan J Obstet Gynecol
PUBLISHED: 02-20-2014
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To report a case of isolated omental peritoneal carcinoma without peritoneal carcinomatosis.
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Spontaneous ureteral rupture and review of the literature.
Am J Emerg Med
PUBLISHED: 02-16-2014
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Spontaneous ureteral rupture is defined as non-traumatic urinary leakage from the ureter. This is a diagnosis that, although uncommon, is important for emergency physicians to know about. The literature is relatively sparse.
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Implementation of dipolar resonant excitation for collision induced dissociation with ion mobility/time-of-flight MS.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 01-28-2014
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An ion mobility/time-of-flight mass spectrometer (IMS/TOF MS) platform that allows for resonant excitation collision induced dissociation (CID) is presented. Highly efficient, mass-resolved fragmentation without additional excitation of product ions was accomplished and over-fragmentation common in beam-type CID experiments was alleviated. A quadrupole ion guide was modified to apply a dipolar AC signal across a pair of rods for resonant excitation. The method was characterized with singly protonated methionine enkephalin and triply protonated peptide angiotensin I, yielding maximum CID efficiencies of 44% and 84%, respectively. The Mathieu q(x,y) parameter was set at 0.707 for these experiments to maximize pseudopotential well depths and CID efficiencies. Resonant excitation CID was compared with beam-type CID for the peptide mixture. The ability to apply resonant waveforms in mobility-resolved windows is demonstrated with a peptide mixture yielding fragmentation over a range of mass-to-charge (m/z) ratios within a single IMS-MS analysis.
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Improving specific activity and thermostability of Escherichia coli phytase by structure-based rational design.
J. Biotechnol.
PUBLISHED: 01-27-2014
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Escherichia coli phytase (EcAppA) which hydrolyzes phytate has been widely applied in the feed industry, but the need to improve the enzyme activity and thermostability remains. Here, we conduct rational design with two strategies to enhance the EcAppA performance. First, residues near the substrate binding pocket of EcAppA were modified according to the consensus sequence of two highly active Citrobacter phytases. One out of the eleven mutants, V89T, exhibited 17.5% increase in catalytic activity, which might be a result of stabilized protein folding. Second, the EcAppA glycosylation pattern was modified in accordance with the Citrobacter phytases. An N-glycosylation motif near the substrate binding site was disrupted to remove spatial hindrance for phytate entry and product departure. The de-glycosylated mutants showed 9.6% increase in specific activity. On the other hand, the EcAppA mutants that adopt N-glycosylation motifs from CbAppA showed improved thermostability that three mutants carrying single N-glycosylation motif exhibited 5.6-9.5% residual activity after treatment at 80°C (1.8% for wild type). Furthermore, the mutant carrying all three glycosylation motifs exhibited 27% residual activity. In conclusion, a successful rational design was performed to obtain several useful EcAppA mutants with better properties for further applications.
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Improving the specific activity of ?-mannanase from Aspergillus niger BK01 by structure-based rational design.
Biochim. Biophys. Acta
PUBLISHED: 01-22-2014
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?-Mannanase has found various biotechnological applications because it is capable of degrading mannans into smaller sugar components. A highly potent example is the thermophilic ?-mannanase from Aspergillus niger BK01 (ManBK), which can be efficiently expressed in industrial yeast strains and is thus an attractive candidate for commercial utilizations. In order to understand the molecular mechanism, which helps in strategies to improve the enzyme's performance that would meet industrial demands, 3D-structural information is a great asset. Here, we present the 1.57Å crystal structure of ManBK. The protein adopts a typical (?/?)8 fold that resembles the other GH5 family members. Polysaccharides were subsequently modeled into the substrate binding groove to identify the residues and structural features that may be involved in the catalytic reaction. Based on the structure, rational design was conducted to engineer ManBK in an attempt to enhance its enzymatic activity. Among the 23 mutants that we constructed, the most promising Y216W showed an 18±2.7% increase in specific activity by comparison with the wild type enzyme. The optimal temperature and heat tolerance profiles of Y216W were similar to those of the wild type, manifesting a preserved thermostability. Kinetic studies showed that Y216W has higher kcat values than the wild type enzyme, suggesting a faster turnover rate of catalysis. In this study we applied rational design to ManBK by using its crystal structure as a basis and identified the Y216W mutant that shows great potentials in industrial applications.
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Cu(I)-catalyzed synthesis of dihydropyrimidin-4-ones toward the preparation of ?- and ?3-amino acid analogues.
J. Org. Chem.
PUBLISHED: 01-22-2014
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A copper(I)-catalyzed synthesis of substituted dihydropyrimidin-4-ones from propargyl amides via the formation of ketenimine intermediate has been successfully developed; the synthesis afforded good isolated yields (80-95%). The mild reaction conditions at room temperature allow the reaction to proceed to completion in a few hours without altering the stereochemistry. Further, by involving a variety of reactive nucleophiles, the obtained substituted dihydropyrimidin-4-ones were elegantly transformed into the corresponding ?- and ?(3)-amino acid analogues.
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Preliminary X-ray diffraction analysis of thermostable ?-1,4-xylanase from Streptomyces sp. S9.
Acta Crystallogr F Struct Biol Commun
PUBLISHED: 01-15-2014
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Xylanase, which catalyzes the random hydrolysis of internal xylosidic linkages, is a critical enzyme participating in xylan decomposition and has been widely applied in industrial utilizations. Xylanase isolated from the extremophilic Streptomyces sp. S9 (XynAS9) possesses broad adaptability to temperature and pH and thus is an attractive candidate in industrial applications. In particular, the major products of XynAS9 are xylose and xylobiose, which enable the subsequent bioconversion to be carried out with higher efficiency. Therefore, the three-dimensional structure of XynAS9 and its catalytic machinery are of great interest. Here, recombinant XynAS9 protein was expressed in Pichia pastoris, purified and crystallized. Crystals belonging to the hexagonal space group P6(5)22, with unit-cell parameters a = b = 80.9, c = 289.3?Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 2.08?Å resolution. Initial phase determination using molecular replacement indicated that the crystal contains one molecule in an asymmetric unit. Further model building and structural refinement are in progress.
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Combined effects of circulating levels of 25-hydroxyvitamin d and Th1 and th2 cytokines on breast cancer estrogen receptor status.
Cancers (Basel)
PUBLISHED: 01-09-2014
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Vitamin D has been recognized for its immune-modulating properties. We have previously found that levels of 25OHD, and cytokines including IL5, IFN?2, and TNF?, are also associated with estrogen receptor (ER) negative breast cancer in younger women. Thus, we hypothesized that there may be interactions between vitamin D and the immune system in influencing breast cancer ER status, which was tested in 490 women with incident breast cancer. There was no correlation of the levels of 25OHD with any cytokine, and their associations with tumor ER negative status were independent of each other. However, premenopausal women with low 25OHD and high TNF? levels had the highest likelihood of having ER negative cancer (odds ratio [OR] = 7.32, 95% confidence interval [CI] = 2.44-21.98), with evidence of synergy between the two (relative excess risk due to interaction [RERI] = 5.46, p for additive interaction = 0.14, and p for multiplicative interaction = 0.09). There were similar synergistic associations between 25OHD and IL5, and several IFN?2 to Th2 cytokine ratios. This is the first study to provide evidence of interactions between vitamin D and the immune system in relation to breast cancer ER status, which may inform combinational use of vitamin D and anti-inflammatory drugs for cancer prevention and therapy.
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Validating a rapid, real-time, PCR-based direct mutation detection assay for preimplantation genetic diagnosis.
Gene
PUBLISHED: 01-06-2014
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Although co-amplification of polymorphic microsatellite markers is the current gold standard for preimplantation genetic diagnosis (PGD) of single-gene disorders (SGD), this approach can be hampered by the lack of availability of informative markers. We recently (2011) devised a novel in-house assay for PGD of aromatic L-amino acid decarboxylase deficiency, based on an amplification refractory mutation system and quantitative PCR (ARMS-qPCR). The objective of the present study was to verify ARMS-qPCR in a cohort of 20 PGD cycles with a diverse group of SGDs (15 couples at risk for 10 SGDs). Day-3 cleavage-stage embryos were subjected to biopsy and genotyping, followed by fresh embryo transfer (FET). The diagnostic rate was 82.9%; unaffected live births were achieved in 9 of 20 FET cycles (45%), with only one false negative (among 54 transferred embryos). Overall, the ARMS-qPCR had frequent allele-dropout (ADO), rendering it inappropriate as the sole diagnostic method (despite a favorable live-birth rate). Regardless, it has the potential to complement the current gold-standard methodology, especially when trophectoderm biopsy becomes a preferred option and genotyping needs to be timely enough to enable FET.
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Virulence Diversity among Bacteremic Aeromonas Isolates: Ex Vivo, Animal, and Clinical Evidences.
PLoS ONE
PUBLISHED: 01-01-2014
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The objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections.
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Outcomes and characteristics of patients undergoing percutaneous angioplasty followed by below-knee or above-knee amputation for peripheral artery disease.
PLoS ONE
PUBLISHED: 01-01-2014
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Little is known about long-term outcomes among patients who receive percutaneous angioplasty (PTA) for peripheral artery disease (PAD) then undergo below-knee or above-knee amputations. We sought to determine clinical outcomes associated with below-knee or above-knee amputation, along with possible explanatory factors and treatment strategies.
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Bone health history in breast cancer patients on aromatase inhibitors.
PLoS ONE
PUBLISHED: 01-01-2014
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A cross-sectional study was performed to assess bone health history among aromatase inhibitor (AI) users before breast cancer (BC) diagnosis, which may impact fracture risk after AI therapy and choice of initial hormonal therapy. A total of 2,157 invasive BC patients initially treated with an AI were identified from a prospective cohort study at Kaiser Permanente Northern California (KPNC). Data on demographic and lifestyle factors were obtained from in-person interviews, and bone health history and clinical data from KPNC clinical databases. The prevalence of osteoporosis and fractures in postmenopausal AI users was assessed, compared with 325 postmenopausal TAM users. The associations of bone health history with demographic and lifestyle factors in AI users were also examined. Among all initial AI users, 11.2% had a prior history of osteoporosis, 16.3% had a prior history of any fracture, and 4.6% had a prior history of major fracture. Postmenopausal women who were taking TAM as their initial hormonal therapy had significantly higher prevalence of prior osteoporosis than postmenopausal AI users (21.5% vs. 11.8%, p<0.0001). Among initial AI users, the associations of history of osteoporosis and fracture in BC patients with demographic and lifestyle factors were, in general, consistent with those known in healthy older women. This study is one of the first to characterize AI users and risk factors for bone morbidity before BC diagnosis. In the future, this study will examine lifestyle, molecular, and genetic risk factors for AI-induced fractures.
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The impact of inadequate terminal disinfection on an outbreak of imipenem-resistant Acinetobacter baumannii in an intensive care unit.
PLoS ONE
PUBLISHED: 01-01-2014
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This study was conducted to investigate an outbreak caused by imipenem-resistant Acinetobacter baumannii (IRAB) in a medical intensive care unit (ICU) in a regional hospital.
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Broad-spectrum transgenic resistance against distinct tospovirus species at the genus level.
PLoS ONE
PUBLISHED: 01-01-2014
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Thrips-borne tospoviruses cause severe damage to crops worldwide. In this investigation, tobacco lines transgenic for individual WLm constructs containing the conserved motifs of the L RNA-encoded RNA-dependent RNA polymerase (L) gene of Watermelon silver mottle virus (WSMoV) were generated by Agrobacterium-mediated transformation. The WLm constructs included: (i) translatable WLm in a sense orientation; (ii) untranslatable WLmt with two stop codons; (iii) untranslatable WLmts with stop codons and a frame-shift; (iv) untranslatable antisense WLmA; and (v) WLmhp with an untranslatable inverted repeat of WLm containing the tospoviral S RNA 3'-terminal consensus sequence (5'-ATTGCTCT-3') and an NcoI site as a linker to generate a double-stranded hairpin transcript. A total of 46.7-70.0% transgenic tobacco lines derived from individual constructs showed resistance to the homologous WSMoV; 35.7-100% plants of these different WSMoV-resistant lines exhibited broad-spectrum resistance against four other serologically unrelated tospoviruses Tomato spotted wilt virus, Groundnut yellow spot virus, Impatiens necrotic spot virus and Groundnut chlorotic fan-spot virus. The selected transgenic tobacco lines also exhibited broad-spectrum resistance against five additional tospoviruses from WSMoV and Iris yellow spot virus clades, but not against RNA viruses from other genera. Northern analyses indicated that the broad-spectrum resistance is mediated by RNA silencing. To validate the L conserved region resistance in vegetable crops, the constructs were also used to generate transgenic tomato lines, which also showed effective resistance against WSMoV and other tospoviruses. Thus, our approach of using the conserved motifs of tospoviral L gene as a transgene generates broad-spectrum resistance against tospoviruses at the genus level.
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Clinical and angiographic outcomes after intracoronary bare-metal stenting.
PLoS ONE
PUBLISHED: 01-01-2014
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Data from a large patient population regarding very long-term outcomes after BMS implantation are inadequate. This study aimed to evaluate the very long-term (8-17 years) clinical and long-term (3-5 years) angiographic outcomes after intracoronary bare-metal stenting (BMS).
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Baseline tumor growth and immune control in laboratory mice are significantly influenced by subthermoneutral housing temperature.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-18-2013
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We show here that fundamental aspects of antitumor immunity in mice are significantly influenced by ambient housing temperature. Standard housing temperature for laboratory mice in research facilities is mandated to be between 20-26 °C; however, these subthermoneutral temperatures cause mild chronic cold stress, activating thermogenesis to maintain normal body temperature. When stress is alleviated by housing at thermoneutral ambient temperature (30-31 °C), we observe a striking reduction in tumor formation, growth rate and metastasis. This improved control of tumor growth is dependent upon the adaptive immune system. We observe significantly increased numbers of antigen-specific CD8(+) T lymphocytes and CD8(+) T cells with an activated phenotype in the tumor microenvironment at thermoneutrality. At the same time there is a significant reduction in numbers of immunosuppressive MDSCs and regulatory T lymphocytes. Notably, in temperature preference studies, tumor-bearing mice select a higher ambient temperature than non-tumor-bearing mice, suggesting that tumor-bearing mice experience a greater degree of cold-stress. Overall, our data raise the hypothesis that suppression of antitumor immunity is an outcome of cold stress-induced thermogenesis. Therefore, the common approach of studying immunity against tumors in mice housed only at standard room temperature may be limiting our understanding of the full potential of the antitumor immune response.
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A mild removal of Fmoc group using sodium azide.
Amino Acids
PUBLISHED: 10-03-2013
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A mild method for effectively removing the fluorenylmethoxycarbonyl (Fmoc) group using sodium azide was developed. Without base, sodium azide completely deprotected N (?)-Fmoc-amino acids in hours. The solvent-dependent conditions were carefully studied and then optimized by screening different sodium azide amounts and reaction temperatures. A variety of Fmoc-protected amino acids containing residues masked with different protecting groups were efficiently and selectively deprotected by the optimized reaction. Finally, a biologically significant hexapeptide, angiotensin IV, was successfully synthesized by solid phase peptide synthesis using the developed sodium azide method for all Fmoc removals. The base-free condition provides a complement method for Fmoc deprotection in peptide chemistry and modern organic synthesis.
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Parity and breastfeeding among African-American women: differential effects on breast cancer risk by estrogen receptor status in the Womens Circle of Health Study.
Cancer Causes Control
PUBLISHED: 08-15-2013
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It has long been held that parity reduces risk of breast cancer. However, accumulating evidence indicates that the effects of parity, as well as breastfeeding, may vary according to estrogen receptor (ER) status. We evaluated these associations in a case-control study among African-American women in New York City and New Jersey.
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Noniterative data inversion of phase retrieval by omega oscillating filtering for optical arbitrary waveform measurement.
Opt Lett
PUBLISHED: 08-14-2013
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We propose a noniterative data inversion process for the phase retrieval by omega oscillating filtering method that could measure both isolated attosecond pulses and periodic optical arbitrary waveform (OAW). The built-in phase modulation depth recovery not only prevents the need of independent calibration (a critical advantage in the extreme ultraviolet regime) but provides a self-consistency check for the data integrity. Our experiments successfully retrieved OAW with ~100% duty cycle in the near infrared regime.
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Structural and mutagenetic analyses of a 1,3-1,4-?-glucanase from Paecilomyces thermophila.
Biochim. Biophys. Acta
PUBLISHED: 08-11-2013
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The thermostable 1,3-1,4-?-glucanase PtLic16A from the fungus Paecilomyces thermophila catalyzes stringent hydrolysis of barley ?-glucan and lichenan with an outstanding efficiency and has great potential for broad industrial applications. Here, we report the crystal structures of PtLic16A and an inactive mutant E113A in ligand-free form and in complex with the ligands cellobiose, cellotetraose and glucotriose at 1.80Å to 2.25Å resolution. PtLic16A adopts a typical ?-jellyroll fold with a curved surface and the concave face forms an extended ligand binding cleft. These structures suggest that PtLic16A might carry out the hydrolysis via retaining mechanism with E113 and E118 serving as the nucleophile and general acid/base, respectively. Interestingly, in the structure of E113A/1,3-1,4-?-glucotriose complex, the sugar bound to the -1 subsite adopts an intermediate-like (?-anomeric) configuration. By combining all crystal structures solved here, a comprehensive binding mode for a substrate is proposed. These findings not only help understand the 1,3-1,4-?-glucanase catalytic mechanism but also provide a basis for further enzymatic engineering.
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High-risk human papillomavirus, other than type 16/18, in predominantly older Taiwanese women with high-grade cervical preinvasive lesions.
Taiwan J Obstet Gynecol
PUBLISHED: 08-07-2013
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To investigate the various genotypes of human papillomavirus (HPV) in Taiwanese women patients with abnormal cervical cytology and analyze the associations between HPV types, cervical preinvasive lesions, and the medical characteristics of these patients.
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Epidermal growth factor enhances androgen receptor?mediated bladder cancer progression and invasion via potentiation of AR transactivation.
Oncol. Rep.
PUBLISHED: 07-22-2013
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Androgen receptor (AR) plays a critical role in bladder cancer (BCa) development. Our early studies found AR knock-out mice (with few androgens and deleted AR) failed to develop BCa, yet 50% of castrated mice (with few androgens and existing AR) still developed BCa in an N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) carcinogen-induced BCa mouse model, suggesting the existing AR in BCa of castrated mice may still play important roles in promoting BCa development at the castration level of androgens. The mechanism underlying this and/or which factors potentiate AR function at the castration level of androgen remains unclear. Epidermal growth factor (EGF), a key player in BCa progression, has been demonstrated to be able to potentiate AR transactivation in prostate cancer. In the present study, we found that EGF could increase BCa cell growth, migration and invasion in the presence of AR under the low amount of androgen and EGF was able to potentiate AR transactivation through EGFR by activating PI3K/AKT and MAPK pathway at castration androgen level. The increased suppression effects by EGFR inhibitor of PD168393 on AR function after addition of anti-androgen, Casodex, further suggested AR might play a key role in the effects of EGF on BCa progression and metastasis. Collectively, our results indicate that EGF may be able to potentiate AR transactivation that leads to enhancing BCa progression, which may help us to develop a better therapeutic approach to treat BCa via targeting both EGF and AR signaling.
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VP2 dominated CD4+ T cell responses against enterovirus 71 and cross-reactivity against coxsackievirus A16 and polioviruses in a healthy population.
J. Immunol.
PUBLISHED: 07-17-2013
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Enterovirus 71 (EV71)-associated hand-foot-mouth disease has become a major threat to public health in the Asia-Pacific region. Although T cell immunity is closely correlated with clinical outcomes of EV71 infection, little is known about T cell immunity baseline against EV71 and T cell immunogenecity of EV71 Ags in the population, which has restricted our understanding of immunoprotection mechanisms. In this study, we investigated the cellular immune responses against the four structural Ags of EV71 and determined the immunohierarchy of these Ags in healthy adults. A low frequency of EV71-responsive T cells was detected circulating in peripheral blood, and broad T cell immune responses could be identified in most of the subjects after in vitro expansion. We demonstrated that the VP2 Ag with broad distribution of immunogenic peptides dominates T cell responses against EV71 compared with VP1, VP3, and VP4. Furthermore, the responses were illuminated to be mainly single IFN-?-secreting CD4(+) T cell dependent, indicating the previous natural acute viral infection of the adult population. Conservancy analysis of the immunogenic peptides revealed that moderately variant peptides were in the majority in coxsackievirus A16 (CV-A16) whereas most of the peptides were highly variant in polioviruses. Less efficient cross-reactivity against CV-A16 might broadly exist among individuals, whereas influences derived from poliovirus vaccination would be limited. Our findings suggest that the significance of VP2 Ag should be addressed in the future EV71-responsive immunological investigations. And the findings concerning the less efficient cross-reactivity against CV-A16 and limited influences from poliovirus vaccination in EV71-contacted population would contribute to a better understanding of immunoprotection mechanisms against enteroviruses.
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A linearization time-domain CMOS smart temperature sensor using a curvature compensation oscillator.
Sensors (Basel)
PUBLISHED: 07-12-2013
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This paper presents an area-efficient time-domain CMOS smart temperature sensor using a curvature compensation oscillator for linearity enhancement with a -40 to 120 °C temperature range operability. The inverter-based smart temperature sensors can substantially reduce the cost and circuit complexity of integrated temperature sensors. However, a large curvature exists on the temperature-to-time transfer curve of the inverter-based delay line and results in poor linearity of the sensor output. For cost reduction and error improvement, a temperature-to-pulse generator composed of a ring oscillator and a time amplifier was used to generate a thermal sensing pulse with a sufficient width proportional to the absolute temperature (PTAT). Then, a simple but effective on-chip curvature compensation oscillator is proposed to simultaneously count and compensate the PTAT pulse with curvature for linearization. With such a simple structure, the proposed sensor possesses an extremely small area of 0.07 mm2 in a TSMC 0.35-mm CMOS 2P4M digital process. By using an oscillator-based scheme design, the proposed sensor achieves a fine resolution of 0.045 °C without significantly increasing the circuit area. With the curvature compensation, the inaccuracy of -1.2 to 0.2 °C is achieved in an operation range of -40 to 120 °C after two-point calibration for 14 packaged chips. The power consumption is measured as 23 mW at a sample rate of 10 samples/s.
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Characterization of a DAPI-RIT-DAPI System for Gas-Phase Ion/Molecule and Ion/Ion Reactions.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 07-10-2013
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The discontinuous atmospheric pressure interface (DAPI) has been developed as a facile means for efficiently introducing ions generated at atmospheric pressure to an ion trap in vacuum [e.g., a rectilinear ion trap (RIT)] for mass analysis. Introduction of multiple beams of ions or neutral species through two DAPIs into a single RIT has been previously demonstrated. In this study, a home-built instrument with a DAPI-RIT-DAPI configuration has been characterized for the study of gas-phase ion/molecule and ion/ion reactions. The reaction species, including ions or neutrals, can be introduced from both ends of the RIT through the two DAPIs without complicated ion optics or differential pumping stages. The primary reactant ions were isolated prior to reaction and the product ions were mass analyzed after controlled reaction time period. Ion/molecule reactions involving peptide radical ions and proton-transfer ion/ion reactions have been carried out using this instrument. The gas dynamic effect due to the DAPI operation on internal energy deposition and the reactivity of peptide radical ions has been characterized. The DAPI-RIT-DAPI system also has a unique feature for allowing the ion reactions to be carried out at significantly elevated pressures (in 10(-1) Torr range), which has been found to be helpful to speed up the reactions. The viability and flexibility of the DAPI-RIT-DAPI system for the study of gas-phase ion reactions have been demonstrated.
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Studies of efficacy and liver toxicity related to adeno-associated virus-mediated RNA interference.
Hum. Gene Ther.
PUBLISHED: 07-09-2013
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Adeno-associated virus (AAV)-mediated RNA interference shows promise as a therapy for chronic hepatitis B virus (HBV) infection, but its low efficacy and hepatotoxicity pose major challenges. We have generated AAV vectors containing different promoters and a panel of HBV-specific short hairpin RNAs (shRNAs) to investigate factors that contribute to the efficacy and pathogenesis of AAV-mediated RNA interference. HBV transgenic mice injected with high doses of AAV vectors containing the U6 promoter produced abundant shRNAs, transiently inhibited HBV, but induced severe hepatotoxicity. Sustained HBV suppression without liver toxicity can be achieved by lowering the dose of AAV-U6 vectors. AAVs containing the weaker H1 promoter did not cause liver injury, but their therapeutic efficacy was highly dependent on the sequence of the shRNA. Mice treated with the toxic U6-promoter-driven shRNA showed little change in hepatic microRNA levels, but a dramatic increase in hepatic leukocytes and inflammatory cytokines and chemokines. Hepatotoxicity was completely absent in immunodeficient mice and significantly alleviated in wild-type mice depleted of macrophages and granulocytes, suggesting that host inflammatory responses are the major cause of liver injury induced by the overexpressed shRNAs from AAV-U6 vectors. Our results demonstrate that selection of a highly potent shRNA and control its expression level is critical to achieve sustained HBV suppression without inducing inflammatory side effects.
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Preliminary X-ray diffraction analysis of thermostable ?-1,4-mannanase from Aspergillus niger BK01.
Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun.
PUBLISHED: 07-05-2013
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?-1,4-Mannanase (?-mannanase) is a key enzyme in decomposing mannans, which are abundant components of hemicelluloses in the plant cell wall. Therefore, mannan hydrolysis is highly valuable in a wide array of industrial applications. ?-Mannanase isolated from Aspergillus niger BK01 (ManBK) was classified into glycoside hydrolase family GH5. ManBK holds great potential in biotechnological applications owing to its high thermostability. Here, ManBK was expressed and purified in Pichia pastoris and the recombinant protein was crystallized. Crystals belonging to the orthorhombic space group C222?, with unit-cell parameters a=93.58, b=97.05, c=147.84?Å, were obtained by the sitting-drop vapour-diffusion method and diffracted to 1.57?Å resolution. Structure determination using molecular-replacement methods is in progress.
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Intratympanic steroid injection for sudden sensorineural hearing loss in a patient on hemodialysis.
Hemodial Int
PUBLISHED: 06-18-2013
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Sudden sensorineural hearing loss (SSNHL) is being described with increasing incidence among patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD). There are no widely accepted guidelines in the medical literature for the appropriate management of this medical emergency. Administration of systemic steroids remains the mainstay of the management of SSNHL in conjunction with the supportive treatment, in this vulnerable group of patients, as well. However, encouraged by the evolving evidence on the efficacy of the intratympanic steroid injections (ITSI) in the treatment of SSNHL among patients without renal disease-we successfully treated SSNHL in an elderly diabetic with sepsis due to bilateral pneumonitis undergoing regular HD treatment with multiple ITSI and antibiotics resulting in complete recovery of hearing function within 3 months of onset of the first symptoms.
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Long-term outcomes of drug-eluting stents versus bare-metal stents in large coronary arteries.
Int. J. Cardiol.
PUBLISHED: 06-15-2013
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Long-term (>3 years) outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in large coronary arteries were not conclusive. In addition, large coronary vessels were defined using a wide size range (?3.0 mm) in previous studies. The aim of this study was to assess the long-term efficacy of DES versus BMS in subgroups of different vessel sizes.
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Associations of dietary folate, Vitamins B6 and B12 and methionine intake with risk of breast cancer among African American and European American women.
Int. J. Cancer
PUBLISHED: 05-17-2013
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African American (AA) women are more likely than European American (EA) women to be diagnosed with breast cancer at younger ages and to develop poor prognosis tumors. However, these racial differences are largely unexplained. Folate and other methyl-group nutrients may be related to breast carcinogenesis, but few studies have examined these associations in AA populations. We examined the associations of dietary intake of these nutrients with breast cancer risk overall, by menopausal and estrogen receptor (ER) status among 1,582 AA (749 cases) and 1,434 EA (744 cases) women using data from a case-control study, the Womens Circle of Health Study. Unconditional multivariable logistic regression models were used to compute odds ratios (ORs) and 95% confidence intervals (CIs) for the association of each nutrient and breast cancer risk. In AA women, inverse associations were observed for natural food folate intake among premenopausal women (fourth vs. first quartile: OR?=?0.57, 95% CI, 0.33-1.00; p for trend?=?0.06) and for ER-positive tumors (fourth vs. first quartile: OR?=?0.58, 95% CI, 0.36-0.93; p for trend?=?0.03), whereas in EA women, a positive association was observed for intake of synthetic folate (fourth vs. first quartile: OR?=?1.53, 95% CI, 1.06-2.21; p for trend?=?0.03). Our findings suggest that natural food folate intake is inversely associated with breast cancer risk and that this association may vary by race, menopausal status or ER status. The finding of an increased risk observed among EA women with the highest intake of synthetic folate from fortified foods warrants further investigation.
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The correlations of sexual activity, sleep problems, emotional distress, attachment styles with quality of life: comparison between gynaecological cancer survivors and noncancer women.
J Clin Nurs
PUBLISHED: 05-08-2013
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AIMS AND OBJECTIVES: To compare quality of life and its related factors, which include sexual activity, sleep problems, depression, anxiety and attachment styles in close relationships, between gynaecological cancer survivors and noncancer women. BACKGROUND: The majority of studies focus on examining the relationships between the late-treatment side effects and quality of life in gynaecological cancer survivors. As a result, there is insufficient information about what are the correlations between psychosocial factors and quality of life in gynaecological cancer survivors. DESIGN: Cross-sectional study. METHODS: The quality of life of the 85 gynaecological cancer patients who had completed active treatments for at least six months was compared with the 85 age-matched women without cancer history. Measures included SF-12 Health Surveys, Medical Outcomes Study Sleep Scale, Beck Depression Inventory-II, State-Trait Anxiety Inventory, Sexual Activity Questionnaire and Experiences in Close Relationships-Revised. RESULTS: There were no significant differences in the quality of life between gynaecological cancer survivors and noncancer women. However, higher attachment-related anxiety in close relationship was the main factor associated with the lower physical quality of life in the gynaecological cancer survivor group. In contrast, older ages were correlated with lower physical quality of life in noncancer women. Anxiety level was the main factor associated with lower mental quality of life for both groups. CONCLUSIONS: Different from noncancer women, the psychosocial factor of insecure attachment in close relationships was the main factor associated with physical quality of life for gynaecological cancer survivors. Anxiety status was the common factor correlated with mental quality of life for cancer and noncancer women. RELEVANCE TO CLINICAL PRACTICE: Developing psychosocial interventions focusing on secure attachment in close relationships and anxiety management could improve physical and mental components of quality of life among gynaecological cancer survivors.
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Oxidative stress and nucleic acid oxidation in patients with chronic kidney disease.
Oxid Med Cell Longev
PUBLISHED: 05-07-2013
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Patients with chronic kidney disease (CKD) have high cardiovascular mortality and morbidity and a high risk for developing malignancy. Excessive oxidative stress is thought to play a major role in elevating these risks by increasing oxidative nucleic acid damage. Oxidative stress results from an imbalance between reactive oxygen/nitrogen species (RONS) production and antioxidant defense mechanisms and can cause vascular and tissue injuries as well as nucleic acid damage in CKD patients. The increased production of RONS, impaired nonenzymatic or enzymatic antioxidant defense mechanisms, and other risk factors including gene polymorphisms, uremic toxins (indoxyl sulfate), deficiency of arylesterase/paraoxonase, hyperhomocysteinemia, dialysis-associated membrane bioincompatibility, and endotoxin in patients with CKD can inhibit normal cell function by damaging cell lipids, arachidonic acid derivatives, carbohydrates, proteins, amino acids, and nucleic acids. Several clinical biomarkers and techniques have been used to detect the antioxidant status and oxidative stress/oxidative nucleic acid damage associated with long-term complications such as inflammation, atherosclerosis, amyloidosis, and malignancy in CKD patients. Antioxidant therapies have been studied to reduce the oxidative stress and nucleic acid oxidation in patients with CKD, including alpha-tocopherol, N-acetylcysteine, ascorbic acid, glutathione, folic acid, bardoxolone methyl, angiotensin-converting enzyme inhibitor, and providing better dialysis strategies. This paper provides an overview of radical production, antioxidant defence, pathogenesis and biomarkers of oxidative stress in patients with CKD, and possible antioxidant therapies.
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Interferon-gamma in ascites could be a predictive biomarker of outcome in ovarian carcinoma.
Gynecol. Oncol.
PUBLISHED: 04-23-2013
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The ovarian cancer-associated ascites is an ideal material for evaluating the interaction between the host immune system and cancer cells in the tumor micro-environment. The aim of this study was to investigate whether the selected target cytokine expression levels in ascites could serve as an immune biomarker for predicting outcomes in ovarian cancer.
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Cytokine and cytokine receptor genes of adaptive immune response are differentially associated with breast cancer risk in American women of African and European ancestry.
Int. J. Cancer
PUBLISHED: 04-15-2013
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Disparities in breast cancer biology are evident between American women of African ancestry (AA) and European ancestry (EA), and may be due, in part, to differences in immune function. To assess the potential role of constitutional host immunity on breast carcinogenesis, we tested associations between breast cancer risk and 47 single nucleotide polymorphisms (SNPs) in 26 cytokine-related genes of the adaptive immune system using 650 EA (n=335 cases) and 864 AA (n=458 cases) women from the Womens Circle of Health Study (WCHS). With additional participant accrual to the WCHS, promising SNPs from the initial analysis were evaluated in a larger sample size (1307 EAs and 1365 AAs). Multivariate logistic regression found SNPs in genes important for T helper type 1 (Th1) immunity (IFNGR2 rs1059293, IL15RA rs2296135, LTA rs1041981), Th2 immunity (IL4R rs1801275), and T regulatory cell-mediated immunosuppression (TGFB1 rs1800469), associated with breast cancer risk, mainly among AAs. The combined effect of these five SNPs was highly significant among AAs (P-trend=0.0005). When stratified by estrogen receptor (ER) status, LTA rs1041981 was associated with ER positive breast cancers among EAs and marginally among AAs. Among AA women only, IL15 rs10833 and IL15RA rs2296135 were associated with ER positive tumors, and IL12RB1 rs375947, IL15 rs10833 and TGFB1 rs1800469 were associated with ER negative tumors. Our study systematically identified genetic variants in the adaptive immune response pathway associated with breast cancer risk, which appears to differ by ancestry groups, menopausal status and ER status. © 2013 Wiley Periodicals, Inc.
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Acute and long-term outcomes of ostial stentings among bare-metal stents, sirolimus-eluting stents, and paclitaxel-eluting stents.
Coron. Artery Dis.
PUBLISHED: 04-11-2013
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The aim of this study is to evaluate the acute and long-term outcomes of ostial stentings among bare-metal stents (BMS), sirolimus-eluting stents, and paclitaxel-eluting stents.
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