JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Vitamin D Therapy in Individuals with Pre-Hypertension or Hypertension: The DAYLIGHT Trial.
Circulation
PUBLISHED: 11-01-2014
Show Abstract
Hide Abstract
-A large body of epidemiological and experimental evidence suggests that vitamin D deficiency may promote hypertension. This raises the possibility that vitamin D supplementation could be a simple intervention to reduce blood pressure, but data from prospective, randomized trials are limited.
Related JoVE Video
Effect of phosphodiesterase inhibition on insulin resistance in obese individuals.
J Am Heart Assoc
PUBLISHED: 09-13-2014
Show Abstract
Hide Abstract
Obesity is associated with cardiometabolic disease, including insulin resistance (IR) and diabetes. Cyclic guanosine monophosphate (cGMP) signaling affects energy balance, IR, and glucose metabolism in experimental models. We sought to examine effects of phosphodiesterase-5 inhibition with tadalafil on IR in a pilot study of obese nondiabetic individuals.
Related JoVE Video
Hospital Discharge Algorithm Based on Admission HbA1c for the Management of Patients With Type 2 Diabetes.
Diabetes Care
PUBLISHED: 08-28-2014
Show Abstract
Hide Abstract
Effective treatment algorithms are needed to guide diabetes care at hospital discharge in general medicine and surgery patients with type 2 diabetes.
Related JoVE Video
Genetic variants related to height and risk of atrial fibrillation: the cardiovascular health study.
Am. J. Epidemiol.
PUBLISHED: 06-18-2014
Show Abstract
Hide Abstract
Increased height is a known independent risk factor for atrial fibrillation (AF). However, whether genetic determinants of height influence risk is uncertain. In this candidate gene study, we examined the association of 209 height-associated single-nucleotide polymorphisms (SNPs) with incident AF in 3,309 persons of European descent from the Cardiovascular Health Study, a prospective cohort study of older adults (aged ? 65 years) enrolled in 1989-1990. After a median follow-up period of 13.2 years, 879 participants developed incident AF. The height-associated SNPs together explained approximately 10% of the variation in height (P = 6.0 × 10(-8)). Using an unweighted genetic height score, we found a nonsignificant association with risk of AF (per allele, hazard ratio = 1.01, 95% confidence interval: 1.00, 1.02; P = 0.06). In weighted analyses, we found that genetically predicted height was strongly associated with AF risk (per 10 cm, hazard ratio = 1.30, 95% confidence interval: 1.03, 1.64; P = 0.03). Importantly, for all models, the inclusion of actual height completely attenuated the genetic height effect. Finally, we identified 1 nonsynonymous SNP (rs1046934) that was independently associated with AF and may warrant future study. In conclusion, we found that genetic determinants of height appear to increase the risk of AF, primarily via height itself. This approach of examining SNPs associated with an intermediate phenotype should be considered as a method for identifying novel genetic targets.
Related JoVE Video
Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.
Dan E Arking, Sara L Pulit, Lia Crotti, Pim van der Harst, Patricia B Munroe, Tamara T Koopmann, Nona Sotoodehnia, Elizabeth J Rossin, Michael Morley, Xinchen Wang, Andrew D Johnson, Alicia Lundby, Daniel F Gudbjartsson, Peter A Noseworthy, Mark Eijgelsheim, Yuki Bradford, Kirill V Tarasov, Marcus Dörr, Martina Müller-Nurasyid, Annukka M Lahtinen, Ilja M Nolte, Albert Vernon Smith, Joshua C Bis, Aaron Isaacs, Stephen J Newhouse, Daniel S Evans, Wendy S Post, Daryl Waggott, Leo-Pekka Lyytikäinen, Andrew A Hicks, Lewin Eisele, David Ellinghaus, Caroline Hayward, Pau Navarro, Sheila Ulivi, Toshiko Tanaka, David J Tester, Stéphanie Chatel, Stefan Gustafsson, Meena Kumari, Richard W Morris, Asa T Naluai, Sandosh Padmanabhan, Alexander Kluttig, Bernhard Strohmer, Andrie G Panayiotou, Maria Torres, Michael Knoflach, Jaroslav A Hubacek, Kamil Slowikowski, Soumya Raychaudhuri, Runjun D Kumar, Tamara B Harris, Lenore J Launer, Alan R Shuldiner, Alvaro Alonso, Joel S Bader, Georg Ehret, Hailiang Huang, W H Linda Kao, James B Strait, Peter W Macfarlane, Morris Brown, Mark J Caulfield, Nilesh J Samani, Florian Kronenberg, Johann Willeit, , J Gustav Smith, Karin H Greiser, Henriette Meyer zu Schwabedissen, Karl Werdan, Massimo Carella, Leopoldo Zelante, Susan R Heckbert, Bruce M Psaty, Jerome I Rotter, Ivana Kolčić, Ozren Polašek, Alan F Wright, Maura Griffin, Mark J Daly, David O Arnar, Hilma Holm, Unnur Thorsteinsdottir, Joshua C Denny, Dan M Roden, Rebecca L Zuvich, Valur Emilsson, Andrew S Plump, Martin G Larson, Christopher J O'Donnell, Xiaoyan Yin, Marco Bobbo, Adamo P d'Adamo, AnnaMaria Iorio, Gianfranco Sinagra, Angel Carracedo, Steven R Cummings, Michael A Nalls, Antti Jula, Kimmo K Kontula, Annukka Marjamaa, Lasse Oikarinen, Markus Perola, Kimmo Porthan, Raimund Erbel, Per Hoffmann, Karl-Heinz Jöckel, Hagen Kälsch, Markus M Nöthen, Marcel den Hoed, Ruth J F Loos, Dag S Thelle, Christian Gieger, Thomas Meitinger, Siegfried Perz, Annette Peters, Hanna Prucha, Moritz F Sinner, Melanie Waldenberger, Rudolf A de Boer, Lude Franke, Pieter A van der Vleuten, Britt Maria Beckmann, Eimo Martens, Abdennasser Bardai, Nynke Hofman, Arthur A M Wilde, Elijah R Behr, Chrysoula Dalageorgou, John R Giudicessi, Argelia Medeiros-Domingo, Julien Barc, Florence Kyndt, Vincent Probst, Alice Ghidoni, Roberto Insolia, Robert M Hamilton, Stephen W Scherer, Jeffrey Brandimarto, Kenneth Margulies, Christine E Moravec, Fabiola Del Greco M, Christian Fuchsberger, Jeffrey R O'Connell, Wai K Lee, Graham C M Watt, Harry Campbell, Sarah H Wild, Nour E El Mokhtari, Norbert Frey, Folkert W Asselbergs, Irene Mateo Leach, Gerjan Navis, Maarten P van den Berg, Dirk J van Veldhuisen, Manolis Kellis, Bouwe P Krijthe, Oscar H Franco, Albert Hofman, Jan A Kors, André G Uitterlinden, Jacqueline C M Witteman, Lyudmyla Kedenko, Claudia Lamina, Ben A Oostra, Gonçalo R Abecasis, Edward G Lakatta, Antonella Mulas, Marco Orrù, David Schlessinger, Manuela Uda, Marcello R P Markus, Uwe Völker, Harold Snieder, Timothy D Spector, Johan Arnlöv, Lars Lind, Johan Sundström, Ann-Christine Syvänen, Mika Kivimäki, Mika Kähönen, Nina Mononen, Olli T Raitakari, Jorma S Viikari, Vera Adamkova, Stefan Kiechl, María Brión, Andrew N Nicolaides, Bernhard Paulweber, Johannes Haerting, Anna F Dominiczak, Fredrik Nyberg, Peter H Whincup, Aroon D Hingorani, Jean-Jacques Schott, Connie R Bezzina, Erik Ingelsson, Luigi Ferrucci, Paolo Gasparini, James F Wilson, Igor Rudan, Andre Franke, Thomas W Mühleisen, Peter P Pramstaller, Terho J Lehtimäki, Andrew D Paterson, Afshin Parsa, Yongmei Liu, Cornelia M van Duijn, David S Siscovick, Vilmundur Gudnason, Yalda Jamshidi, Veikko Salomaa, Stephan B Felix, Serena Sanna, Marylyn D Ritchie, Bruno H Stricker, Kari Stefansson, Laurie A Boyer, Thomas P Cappola, Jesper V Olsen, Kasper Lage, Peter J Schwartz, Stefan Kääb, Aravinda Chakravarti, Michael J Ackerman, Arne Pfeufer, Paul I W de Bakker, Christopher Newton-Cheh.
Nat. Genet.
PUBLISHED: 05-29-2014
Show Abstract
Hide Abstract
The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ?8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD.
Related JoVE Video
Annotation of loci from genome-wide association studies using tissue-specific quantitative interaction proteomics.
Nat. Methods
PUBLISHED: 05-16-2014
Show Abstract
Hide Abstract
Genome-wide association studies (GWAS) have identified thousands of loci associated with complex traits, but it is challenging to pinpoint causal genes in these loci and to exploit subtle association signals. We used tissue-specific quantitative interaction proteomics to map a network of five genes involved in the Mendelian disorder long QT syndrome (LQTS). We integrated the LQTS network with GWAS loci from the corresponding common complex trait, QT-interval variation, to identify candidate genes that were subsequently confirmed in Xenopus laevis oocytes and zebrafish. We used the LQTS protein network to filter weak GWAS signals by identifying single-nucleotide polymorphisms (SNPs) in proximity to genes in the network supported by strong proteomic evidence. Three SNPs passing this filter reached genome-wide significance after replication genotyping. Overall, we present a general strategy to propose candidates in GWAS loci for functional studies and to systematically filter subtle association signals using tissue-specific quantitative interaction proteomics.
Related JoVE Video
Effects of long-term averaging of quantitative blood pressure traits on the detection of genetic associations.
Am. J. Hum. Genet.
PUBLISHED: 03-13-2014
Show Abstract
Hide Abstract
Blood pressure (BP) is a heritable, quantitative trait with intraindividual variability and susceptibility to measurement error. Genetic studies of BP generally use single-visit measurements and thus cannot remove variability occurring over months or years. We leveraged the idea that averaging BP measured across time would improve phenotypic accuracy and thereby increase statistical power to detect genetic associations. We studied systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP) averaged over multiple years in 46,629 individuals of European ancestry. We identified 39 trait-variant associations across 19 independent loci (p < 5 × 10(-8)); five associations (in four loci) uniquely identified by our LTA analyses included those of SBP and MAP at 2p23 (rs1275988, near KCNK3), DBP at 2q11.2 (rs7599598, in FER1L5), and PP at 6p21 (rs10948071, near CRIP3) and 7p13 (rs2949837, near IGFBP3). Replication analyses conducted in cohorts with single-visit BP data showed positive replication of associations and a nominal association (p < 0.05). We estimated a 20% gain in statistical power with long-term average (LTA) as compared to single-visit BP association studies. Using LTA analysis, we identified genetic loci influencing BP. LTA might be one way of increasing the power of genetic associations for continuous traits in extant samples for other phenotypes that are measured serially over time.
Related JoVE Video
The effect of race on outcomes for appendicitis in children: a nationwide analysis.
Am. J. Surg.
PUBLISHED: 03-12-2014
Show Abstract
Hide Abstract
We sought to examine the impact of race on the management and outcomes of appendicitis in children aged 20 years or younger.
Related JoVE Video
Gene-centric meta-analysis in 87,736 individuals of European ancestry identifies multiple blood-pressure-related loci.
Vinicius Tragante, Michael R Barnes, Santhi K Ganesh, Matthew B Lanktree, Wei Guo, Nora Franceschini, Erin N Smith, Toby Johnson, Michael V Holmes, Sandosh Padmanabhan, Konrad J Karczewski, Berta Almoguera, John Barnard, Jens Baumert, Yen-Pei Christy Chang, Clara C Elbers, Martin Farrall, Mary E Fischer, Tom R Gaunt, Johannes M I H Gho, Christian Gieger, Anuj Goel, Yan Gong, Aaron Isaacs, Marcus E Kleber, Irene Mateo Leach, Caitrin W McDonough, Matthijs F L Meijs, Olle Melander, Christopher P Nelson, Ilja M Nolte, Nathan Pankratz, Tom S Price, Jonathan Shaffer, Sonia Shah, Maciej Tomaszewski, Peter J van der Most, Erik P A van Iperen, Judith M Vonk, Kate Witkowska, Caroline O L Wong, Li Zhang, Amber L Beitelshees, Gerald S Berenson, Deepak L Bhatt, Morris Brown, Amber Burt, Rhonda M Cooper-DeHoff, John M Connell, Karen J Cruickshanks, Sean P Curtis, George Davey-Smith, Christian Delles, Ron T Gansevoort, Xiuqing Guo, Shen Haiqing, Claire E Hastie, Marten H Hofker, G Kees Hovingh, Daniel S Kim, Susan A Kirkland, Barbara E Klein, Ronald Klein, Yun R Li, Steffi Maiwald, Christopher Newton-Cheh, Eoin T O'Brien, N Charlotte Onland-Moret, Walter Palmas, Afshin Parsa, Brenda W Penninx, Mary Pettinger, Ramachandran S Vasan, Jane E Ranchalis, Paul M Ridker, Lynda M Rose, Peter Sever, Daichi Shimbo, Laura Steele, Ronald P Stolk, Barbara Thorand, Mieke D Trip, Cornelia M van Duijn, W Monique Verschuren, Cisca Wijmenga, Sharon Wyatt, J Hunter Young, Aeilko H Zwinderman, Connie R Bezzina, Eric Boerwinkle, Juan P Casas, Mark J Caulfield, Aravinda Chakravarti, Daniel I Chasman, Karina W Davidson, Pieter A Doevendans, Anna F Dominiczak, Garret A FitzGerald, John G Gums, Myriam Fornage, Hakon Hakonarson, Indrani Halder, Hans L Hillege, Thomas Illig, Gail P Jarvik, Julie A Johnson, John J P Kastelein, Wolfgang Koenig, Meena Kumari, Winfried März, Sarah S Murray, Jeffery R O'Connell, Albertine J Oldehinkel, James S Pankow, Daniel J Rader, Susan Redline, Muredach P Reilly, Eric E Schadt, Kandice Kottke-Marchant, Harold Snieder, Michael Snyder, Alice V Stanton, Martin D Tobin, André G Uitterlinden, Pim van der Harst, Yvonne T van der Schouw, Nilesh J Samani, Hugh Watkins, Andrew D Johnson, Alex P Reiner, Xiaofeng Zhu, Paul I W de Bakker, Daniel Levy, Folkert W Asselbergs, Patricia B Munroe, Brendan J Keating.
Am. J. Hum. Genet.
PUBLISHED: 02-20-2014
Show Abstract
Hide Abstract
Blood pressure (BP) is a heritable risk factor for cardiovascular disease. To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP), we genotyped ~50,000 SNPs in up to 87,736 individuals of European ancestry and combined these in a meta-analysis. We replicated findings in an independent set of 68,368 individuals of European ancestry. Our analyses identified 11 previously undescribed associations in independent loci containing 31 genes including PDE1A, HLA-DQB1, CDK6, PRKAG2, VCL, H19, NUCB2, RELA, HOXC@ complex, FBN1, and NFAT5 at the Bonferroni-corrected array-wide significance threshold (p < 6 × 10(-7)) and confirmed 27 previously reported associations. Bioinformatic analysis of the 11 loci provided support for a putative role in hypertension of several genes, such as CDK6 and NUCB2. Analysis of potential pharmacological targets in databases of small molecules showed that ten of the genes are predicted to be a target for small molecules. In summary, we identified previously unknown loci associated with BP. Our findings extend our understanding of genes involved in BP regulation, which may provide new targets for therapeutic intervention or drug response stratification.
Related JoVE Video
Variations in pediatric trauma transfer patterns in Northern California pediatric trauma centers (2001-2009).
Acad Emerg Med
PUBLISHED: 02-10-2014
Show Abstract
Hide Abstract
Due to the scarcity of specialized resources for pediatric trauma, "regionalization," or a system designed to get "the right child, to the right place, at the right time," is vital to quality pediatric trauma care. In Northern California, four pediatric trauma centers serve 3.9 million children within a geographically diverse area of 113,630 square miles. A significant proportion of children with trauma is initially triaged to nontrauma hospitals and may require subsequent transfer to a specialty center. Trauma transfer patterns to a pediatric trauma center may provide insight into regional primary triage practices. Transfers from hospitals in close proximity to pediatric trauma centers might suggest that some children could have avoided transfer with minimal additional transport time. While pediatric trauma centers are scarce and serve as regional resources, transfers from beyond the regular catchment area of a trauma center could be an indication of clinical need.
Related JoVE Video
An enhancer polymorphism at the cardiomyocyte intercalated disc protein NOS1AP locus is a major regulator of the QT interval.
Am. J. Hum. Genet.
PUBLISHED: 01-10-2014
Show Abstract
Hide Abstract
QT interval variation is assumed to arise from variation in repolarization as evidenced from rare Na- and K-channel mutations in Mendelian QT prolongation syndromes. However, in the general population, common noncoding variants at a chromosome 1q locus are the most common genetic regulators of QT interval variation. In this study, we use multiple human genetic, molecular genetic, and cellular assays to identify a functional variant underlying trait association: a noncoding polymorphism (rs7539120) that maps within an enhancer of NOS1AP and affects cardiac function by increasing NOS1AP transcript expression. We further localized NOS1AP to cardiomyocyte intercalated discs (IDs) and demonstrate that overexpression of NOS1AP in cardiomyocytes leads to altered cellular electrophysiology. We advance the hypothesis that NOS1AP affects cardiac electrical conductance and coupling and thereby regulates the QT interval through propagation defects. As further evidence of an important role for propagation variation affecting QT interval in humans, we show that common polymorphisms mapping near a specific set of 170 genes encoding ID proteins are significantly enriched for association with the QT interval, as compared to genome-wide markers. These results suggest that focused studies of proteins within the cardiomyocyte ID are likely to provide insights into QT prolongation and its associated disorders.
Related JoVE Video
Increased Burden of Cardiovascular Disease in Carriers of APOL1 Genetic Variants.
Circ. Res.
PUBLISHED: 12-30-2013
Show Abstract
Hide Abstract
Two distinct alleles in the gene encoding apolipoprotein L1 (APOL1), a major component of HDL, confer protection against Trypanosoma brucei rhodesiense infection and also increase risk for chronic kidney disease (CKD). Approximately 14% of African-Americans carry two APOL1 risk alleles, accounting for the high CKD burden in this population.
Related JoVE Video
Laparoscopy utilization and outcomes for appendicitis in small children.
J. Pediatr. Surg.
PUBLISHED: 10-01-2013
Show Abstract
Hide Abstract
To examine the trends in laparoscopic appendectomy (LA) utilization and outcomes for children 5 years or younger.
Related JoVE Video
The increasing incidence of adolescent bariatric surgery.
J. Pediatr. Surg.
PUBLISHED: 08-16-2013
Show Abstract
Hide Abstract
Morbid obesity continues to be a significant problem within the United States, as overweight/obesity rates are nearing 33%. Bariatric surgery has had success in treating obesity in adults and is becoming a viable treatment option for obese adolescents.
Related JoVE Video
Predictive value of electrocardiographic T-wave morphology parameters and T-wave peak to T-wave end interval for sudden cardiac death in the general population.
Circ Arrhythm Electrophysiol
PUBLISHED: 07-23-2013
Show Abstract
Hide Abstract
Previous population studies have found an association between electrocardiographic T-wave morphology parameters and cardiovascular mortality, but their relationship to sudden cardiac death (SCD) is not clear. To our knowledge, there are no follow-up studies assessing the association between electrocardiographic T-wave peak to T-wave end interval (TPE) and SCD. We assessed the predictive value of electrocardiographic T-wave morphology parameters and TPE for SCD in an adult general population sample.
Related JoVE Video
Safety and efficacy of sitagliptin therapy for the inpatient management of general medicine and surgery patients with type 2 diabetes: a pilot, randomized, controlled study.
Diabetes Care
PUBLISHED: 07-22-2013
Show Abstract
Hide Abstract
This study investigated the safety and efficacy of sitagliptin (Januvia) for the inpatient management of type 2 diabetes (T2D) in general medicine and surgery patients.
Related JoVE Video
Gene-environment interaction between SCN5A-1103Y and hypokalemia influences QT interval prolongation in African Americans: The Jackson Heart Study.
Am. Heart J.
PUBLISHED: 07-02-2013
Show Abstract
Hide Abstract
African-American ancestry, hypokalemia, and QT interval prolongation on the electrocardiogram are all risk factors for sudden cardiac death (SCD), but their interactions remain to be characterized. SCN5A-1103Y is a common missense variant, of African ancestry, of the cardiac sodium channel gene. SCN5A-1103Y is known to interact with QT-prolonging factors to promote ventricular arrhythmias in persons at high risk for SCD, but its clinical impact in the general African-American population has not been established.
Related JoVE Video
Common genetic variation at the IL1RL1 locus regulates IL-33/ST2 signaling.
J. Clin. Invest.
PUBLISHED: 06-27-2013
Show Abstract
Hide Abstract
The suppression of tumorigenicity 2/IL-33 (ST2/IL-33) pathway has been implicated in several immune and inflammatory diseases. ST2 is produced as 2 isoforms. The membrane-bound isoform (ST2L) induces an immune response when bound to its ligand, IL-33. The other isoform is a soluble protein (sST2) that is thought to be a decoy receptor for IL-33 signaling. Elevated sST2 levels in serum are associated with an increased risk for cardiovascular disease. We investigated the determinants of sST2 plasma concentrations in 2,991 Framingham Offspring Cohort participants. While clinical and environmental factors explained some variation in sST2 levels, much of the variation in sST2 production was driven by genetic factors. In a genome-wide association study (GWAS), multiple SNPs within IL1RL1 (the gene encoding ST2) demonstrated associations with sST2 concentrations. Five missense variants of IL1RL1 correlated with higher sST2 levels in the GWAS and mapped to the intracellular domain of ST2, which is absent in sST2. In a cell culture model, IL1RL1 missense variants increased sST2 expression by inducing IL-33 expression and enhancing IL-33 responsiveness (via ST2L). Our data suggest that genetic variation in IL1RL1 can result in increased levels of sST2 and alter immune and inflammatory signaling through the ST2/IL-33 pathway.
Related JoVE Video
Impairments in site-specific AS160 phosphorylation and effects of exercise training.
Diabetes
PUBLISHED: 06-25-2013
Show Abstract
Hide Abstract
The purpose of this study was to determine if site-specific phosphorylation at the level of Akt substrate of 160 kDa (AS160) is altered in skeletal muscle from sedentary humans across a wide range of the adult life span (18-84 years of age) and if endurance- and/or strength-oriented exercise training could rescue decrements in insulin action and skeletal muscle AS160 phosphorylation. A euglycemic-hyperinsulinemic clamp and skeletal muscle biopsies were performed in 73 individuals encompassing a wide age range (18-84 years of age), and insulin-stimulated AS160 phosphorylation was determined. Decrements in whole-body insulin action were associated with impairments in insulin-induced phosphorylation of skeletal muscle AS160 on sites Ser-588, Thr-642, Ser-666, and phospho-Akt substrate, but not Ser-318 or Ser-751. Twelve weeks of endurance- or strength-oriented exercise training increased whole-body insulin action and reversed impairments in AS160 phosphorylation evident in insulin-resistant aged individuals. These findings suggest that a dampening of insulin-induced phosphorylation of AS160 on specific sites in skeletal muscle contributes to the insulin resistance evident in a sedentary aging population and that exercise training is an effective intervention for treating these impairments.
Related JoVE Video
Prevalence, quality of care, and complications in long term care residents with diabetes: a multicenter observational study.
J Am Med Dir Assoc
PUBLISHED: 05-31-2013
Show Abstract
Hide Abstract
Few studies have reported on the quality of diabetes care and glycemic control adjusted for medication use in long term care (LTC) facilities.
Related JoVE Video
Silencing of the Drosophila ortholog of SOX5 in heart leads to cardiac dysfunction as detected by optical coherence tomography.
Hum. Mol. Genet.
PUBLISHED: 05-21-2013
Show Abstract
Hide Abstract
The SRY-related HMG-box 5 (SOX5) gene encodes a member of the SOX family of transcription factors. Recently, genome-wide association studies have implicated SOX5 as a candidate gene for susceptibility to four cardiac-related endophenotypes: higher resting heart rate (HR), the electrocardiographic PR interval, atrial fibrillation and left ventricular mass. We have determined that human SOX5 has a highly conserved Drosophila ortholog, Sox102F, and have employed transgenic Drosophila models to quantitatively measure cardiac function in adult flies. For this purpose, we have developed a high-speed and ultrahigh-resolution optical coherence tomography imaging system, which enables rapid cross-sectional imaging of the heart tube over various cardiac cycles for the measurement of cardiac structural and dynamical parameters such as HR, dimensions and areas of heart chambers, cardiac wall thickness and wall velocities. We have found that the silencing of Sox102F resulted in a significant decrease in HR, heart chamber size and cardiac wall velocities, and a significant increase in cardiac wall thickness that was accompanied by disrupted myofibril structure in adult flies. In addition, the silencing of Sox102F in the wing led to increased L2, L3 and wing marginal veins and increased and disorganized expression of wingless, the central component of the Wnt signaling pathway. Collectively, the silencing of Sox102F resulted in severe cardiac dysfunction and structural defects with disrupted Wnt signaling transduction in flies. This implicates an important functional role for SOX5 in heart and suggests that the alterations in SOX5 levels may contribute to the pathogenesis of multiple cardiac diseases or traits.
Related JoVE Video
Atrial natriuretic peptide is negatively regulated by microRNA-425.
J. Clin. Invest.
PUBLISHED: 05-17-2013
Show Abstract
Hide Abstract
Numerous common genetic variants have been linked to blood pressure, but no underlying mechanism has been elucidated. Population studies have revealed that the variant rs5068 (A/G) in the 3 untranslated region of NPPA, the gene encoding atrial natriuretic peptide (ANP), is associated with blood pressure. We selected individuals on the basis of rs5068 genotype (AG vs. AA) and fed them a low- or high-salt diet for 1 week, after which they were challenged with an intravenous saline infusion. On both diets, before and after saline administration, ANP levels were up to 50% higher in AG individuals than in AA individuals, a difference comparable to the changes induced by high-salt diet or saline infusion. In contrast, B-type natriuretic peptide levels did not differ by rs5068 genotype. We identified a microRNA, miR-425, that is expressed in human atria and ventricles and is predicted to bind the sequence spanning rs5068 for the A, but not the G, allele. miR-425 silenced NPPA mRNA in an allele-specific manner, with the G allele conferring resistance to miR-425. This study identifies miR-425 as a regulator of ANP production, raising the possibility that miR-425 antagonists could be used to treat disorders of salt overload, including hypertension and heart failure.
Related JoVE Video
Prevalence of arrhythmia-associated gene mutations and risk of sudden cardiac death in the Finnish population.
Ann. Med.
PUBLISHED: 05-08-2013
Show Abstract
Hide Abstract
Sudden cardiac death (SCD) remains a major cause of death in Western countries. It has a heritable component, but previous molecular studies have mainly focused on common genetic variants. We studied the prevalence, clinical phenotypes, and risk of SCD presented by ten rare mutations previously associated with arrhythmogenic right ventricular cardiomyopathy, long QT syndrome, or catecholaminergic polymorphic ventricular tachycardia.
Related JoVE Video
Identification of heart rate-associated loci and their effects on cardiac conduction and rhythm disorders.
Marcel den Hoed, Mark Eijgelsheim, Tonu Esko, Bianca J J M Brundel, David S Peal, David M Evans, Ilja M Nolte, Ayellet V Segrè, Hilma Holm, Robert E Handsaker, Harm-Jan Westra, Toby Johnson, Aaron Isaacs, Jian Yang, Alicia Lundby, Jing Hua Zhao, Young Jin Kim, Min Jin Go, Peter Almgren, Murielle Bochud, Gabrielle Boucher, Marilyn C Cornelis, Daniel Gudbjartsson, David Hadley, Pim van der Harst, Caroline Hayward, Martin den Heijer, Wilmar Igl, Anne U Jackson, Zoltan Kutalik, Jian'an Luan, John P Kemp, Kati Kristiansson, Claes Ladenvall, Mattias Lorentzon, May E Montasser, Omer T Njajou, Paul F O'Reilly, Sandosh Padmanabhan, Beate St Pourcain, Tuomo Rankinen, Perttu Salo, Toshiko Tanaka, Nicholas J Timpson, Veronique Vitart, Lindsay Waite, William Wheeler, Weihua Zhang, Harmen H M Draisma, Mary F Feitosa, Kathleen F Kerr, Penelope A Lind, Evelin Mihailov, N Charlotte Onland-Moret, Ci Song, Michael N Weedon, Weijia Xie, Loïc Yengo, Devin Absher, Christine M Albert, Alvaro Alonso, Dan E Arking, Paul I W de Bakker, Beverley Balkau, Cristina Barlassina, Paola Benaglio, Joshua C Bis, Nabila Bouatia-Naji, Søren Brage, Stephen J Chanock, Peter S Chines, Mina Chung, Dawood Darbar, Christian Dina, Marcus Dörr, Paul Elliott, Stephan B Felix, Krista Fischer, Christian Fuchsberger, Eco J C de Geus, Philippe Goyette, Vilmundur Gudnason, Tamara B Harris, Anna-Liisa Hartikainen, Aki S Havulinna, Susan R Heckbert, Andrew A Hicks, Albert Hofman, Suzanne Holewijn, Femke Hoogstra-Berends, Jouke-Jan Hottenga, Majken K Jensen, Asa Johansson, Juhani Junttila, Stefan Kääb, Bart Kanon, Shamika Ketkar, Kay-Tee Khaw, Joshua W Knowles, Angrad S Kooner, Jan A Kors, Meena Kumari, Lili Milani, Päivi Laiho, Edward G Lakatta, Claudia Langenberg, Maarten Leusink, Yongmei Liu, Robert N Luben, Kathryn L Lunetta, Stacey N Lynch, Marcello R P Markus, Pedro Marques-Vidal, Irene Mateo Leach, Wendy L McArdle, Steven A McCarroll, Sarah E Medland, Kathryn A Miller, Grant W Montgomery, Alanna C Morrison, Martina Müller-Nurasyid, Pau Navarro, Mari Nelis, Jeffrey R O'Connell, Christopher J O'Donnell, Ken K Ong, Anne B Newman, Annette Peters, Ozren Polašek, Anneli Pouta, Peter P Pramstaller, Bruce M Psaty, Dabeeru C Rao, Susan M Ring, Elizabeth J Rossin, Diana Rudan, Serena Sanna, Robert A Scott, Jaban S Sehmi, Stephen Sharp, Jordan T Shin, Andrew B Singleton, Albert V Smith, Nicole Soranzo, Tim D Spector, Chip Stewart, Heather M Stringham, Kirill V Tarasov, André G Uitterlinden, Liesbeth Vandenput, Shih-Jen Hwang, John B Whitfield, Cisca Wijmenga, Sarah H Wild, Gonneke Willemsen, James F Wilson, Jacqueline C M Witteman, Andrew Wong, Quenna Wong, Yalda Jamshidi, Paavo Zitting, Jolanda M A Boer, Dorret I Boomsma, Ingrid B Borecki, Cornelia M van Duijn, Ulf Ekelund, Nita G Forouhi, Philippe Froguel, Aroon Hingorani, Erik Ingelsson, Mika Kivimäki, Richard A Kronmal, Diana Kuh, Lars Lind, Nicholas G Martin, Ben A Oostra, Nancy L Pedersen, Thomas Quertermous, Jerome I Rotter, Yvonne T van der Schouw, W M Monique Verschuren, Mark Walker, Demetrius Albanes, David O Arnar, Themistocles L Assimes, Stefania Bandinelli, Michael Boehnke, Rudolf A de Boer, Claude Bouchard, W L Mark Caulfield, John C Chambers, Gary Curhan, Daniele Cusi, Johan Eriksson, Luigi Ferrucci, Wiek H van Gilst, Nicola Glorioso, Jacqueline de Graaf, Leif Groop, Ulf Gyllensten, Wen-Chi Hsueh, Frank B Hu, Heikki V Huikuri, David J Hunter, Carlos Iribarren, Bo Isomaa, Marjo-Riitta Järvelin, Antti Jula, Mika Kähönen, Lambertus A Kiemeney, Melanie M van der Klauw, Jaspal S Kooner, Peter Kraft, Licia Iacoviello, Terho Lehtimäki, Marja-Liisa L Lokki, Braxton D Mitchell, Gerjan Navis, Markku S Nieminen, Claes Ohlsson, Neil R Poulter, Lu Qi, Olli T Raitakari, Eric B Rimm, John D Rioux, Federica Rizzi, Igor Rudan, Veikko Salomaa, Peter S Sever, Denis C Shields, Alan R Shuldiner, Juha Sinisalo, Alice V Stanton, Ronald P Stolk, David P Strachan, Jean-Claude Tardif, Unnur Thorsteinsdottir, Jaako Tuomilehto, Dirk J van Veldhuisen, Jarmo Virtamo, Jorma Viikari, Peter Vollenweider, Gérard Waeber, Elisabeth Widén, Yoon Shin Cho, Jesper V Olsen, Peter M Visscher, Cristen Willer, Lude Franke, , Jeanette Erdmann, John R Thompson, Arne Pfeufer, Nona Sotoodehnia, Christopher Newton-Cheh, Patrick T Ellinor, Bruno H Ch Stricker, Andres Metspalu, Markus Perola, Jacques S Beckmann, George Davey Smith, Kari Stefansson, Nicholas J Wareham, Patricia B Munroe, Ody C M Sibon, David J Milan, Harold Snieder, Nilesh J Samani, Ruth J F Loos.
Nat. Genet.
PUBLISHED: 03-21-2013
Show Abstract
Hide Abstract
Elevated resting heart rate is associated with greater risk of cardiovascular disease and mortality. In a 2-stage meta-analysis of genome-wide association studies in up to 181,171 individuals, we identified 14 new loci associated with heart rate and confirmed associations with all 7 previously established loci. Experimental downregulation of gene expression in Drosophila melanogaster and Danio rerio identified 20 genes at 11 loci that are relevant for heart rate regulation and highlight a role for genes involved in signal transmission, embryonic cardiac development and the pathophysiology of dilated cardiomyopathy, congenital heart failure and/or sudden cardiac death. In addition, genetic susceptibility to increased heart rate is associated with altered cardiac conduction and reduced risk of sick sinus syndrome, and both heart rate-increasing and heart rate-decreasing variants associate with risk of atrial fibrillation. Our findings provide fresh insights into the mechanisms regulating heart rate and identify new therapeutic targets.
Related JoVE Video
Effects of subacute dietary salt intake and acute volume expansion on diastolic function in young normotensive individuals.
Eur Heart J Cardiovasc Imaging
PUBLISHED: 03-20-2013
Show Abstract
Hide Abstract
Chronic excess salt intake may have blood pressure-independent adverse effects on the heart such as myocardial hypertrophy and fibrosis. Effects of subacute sodium loading with excess dietary salt on diastolic function in normotensive individuals have been conflicting and the mechanisms are poorly understood.
Related JoVE Video
Differences in inpatient glycemic control and response to subcutaneous insulin therapy between medicine and surgery patients with type 2 diabetes.
J. Diabetes Complicat.
PUBLISHED: 03-18-2013
Show Abstract
Hide Abstract
To determine differences in inpatient glycemic control and response to two different glargine-based insulin regimens in general medicine and surgery patients with type 2 diabetes (T2D).
Related JoVE Video
A blood pressure genetic risk score is a significant predictor of incident cardiovascular events in 32,669 individuals.
Hypertension
PUBLISHED: 03-18-2013
Show Abstract
Hide Abstract
Recent genome-wide association studies have identified genetic variants associated with blood pressure (BP). We investigated whether genetic risk scores (GRSs) constructed of these variants would predict incident cardiovascular disease (CVD) events. We genotyped 32 common single nucleotide polymorphisms in several Finnish cohorts, with up to 32,669 individuals after exclusion of prevalent CVD cases. The median follow-up was 9.8 years, during which 2295 incident CVD events occurred. We created GRSs separately for systolic BP and diastolic BP by multiplying the risk allele count of each single nucleotide polymorphism by the effect size estimated in published genome-wide association studies. We performed Cox regression analyses with and without adjustment for clinical factors, including BP at baseline in each cohort. The results were combined by inverse variance-weighted fixed-effects meta-analysis. The GRSs were strongly associated with systolic BP and diastolic BP, and baseline hypertension (all P<10(-62)). Hazard ratios comparing the highest quintiles of systolic BP and diastolic BP GRSs with the lowest quintiles after adjustment for age, age squared, and sex were 1.25 (1.07-1.46; P=0.006) and 1.23 (1.05-1.43; P=0.01), respectively, for incident coronary heart disease; 1.24 (1.01-1.53; P=0.04) and 1.35 (1.09-1.66; P=0.005), respectively, for incident stroke; and 1.23 (1.08-1.40; P=2 × 10(-6)) and 1.26 (1.11-1.44; P=5 × 10(-4)), respectively, for composite CVD. In conclusion, BP findings from genome-wide association studies are strongly replicated. GRSs comprising bona fide BP-single nucleotide polymorphisms predicted CVD risk, consistent with a lifelong effect on BP of these variants collectively.
Related JoVE Video
Genetic predisposition to higher blood pressure increases coronary artery disease risk.
Hypertension
PUBLISHED: 03-11-2013
Show Abstract
Hide Abstract
Hypertension is a risk factor for coronary artery disease. Recent genome-wide association studies have identified 30 genetic variants associated with higher blood pressure at genome-wide significance (P<5 × 10(-8)). If elevated blood pressure is a causative factor for coronary artery disease, these variants should also increase coronary artery disease risk. Analyzing genome-wide association data from 22 233 coronary artery disease cases and 64 762 controls, we observed in the Coronary ARtery DIsease Genome-Wide Replication And Meta-Analysis (CARDIoGRAM) consortium that 88% of these blood pressure-associated polymorphisms were likewise positively associated with coronary artery disease, that is, they had an odds ratio >1 for coronary artery disease, a proportion much higher than expected by chance (P=4 × 10(-5)). The average relative coronary artery disease risk increase per each of the multiple blood pressure-raising alleles observed in the consortium was 3.0% for systolic blood pressure-associated polymorphisms (95% confidence interval, 1.8%-4.3%) and 2.9% for diastolic blood pressure-associated polymorphisms (95% confidence interval, 1.7%-4.1%). In substudies, individuals carrying most systolic blood pressure- and diastolic blood pressure-related risk alleles (top quintile of a genetic risk score distribution) had 70% (95% confidence interval, 50%-94%) and 59% (95% confidence interval, 40%-81%) higher odds of having coronary artery disease, respectively, as compared with individuals in the bottom quintile. In conclusion, most blood pressure-associated polymorphisms also confer an increased risk for coronary artery disease. These findings are consistent with a causal relationship of increasing blood pressure to coronary artery disease. Genetic variants primarily affecting blood pressure contribute to the genetic basis of coronary artery disease.
Related JoVE Video
Related JoVE Video
Assessing the phenotypic effects in the general population of rare variants in genes for a dominant Mendelian form of diabetes.
Nat. Genet.
PUBLISHED: 02-11-2013
Show Abstract
Hide Abstract
Genome sequencing can identify individuals in the general population who harbor rare coding variants in genes for Mendelian disorders and who may consequently have increased disease risk. Previous studies of rare variants in phenotypically extreme individuals display ascertainment bias and may demonstrate inflated effect-size estimates. We sequenced seven genes for maturity-onset diabetes of the young (MODY) in well-phenotyped population samples (n = 4,003). We filtered rare variants according to two prediction criteria for disease-causing mutations: reported previously in MODY or satisfying stringent de novo thresholds (rare, conserved and protein damaging). Approximately 1.5% and 0.5% of randomly selected individuals from the Framingham and Jackson Heart Studies, respectively, carry variants from these two classes. However, the vast majority of carriers remain euglycemic through middle age. Accurate estimates of variant effect sizes from population-based sequencing are needed to avoid falsely predicting a substantial fraction of individuals as being at risk for MODY or other Mendelian diseases.
Related JoVE Video
A common missense variant in the neuregulin 1 gene is associated with both schizophrenia and sudden cardiac death.
Heart Rhythm
PUBLISHED: 02-08-2013
Show Abstract
Hide Abstract
Both schizophrenia and epilepsy have been linked to increased risk of sudden cardiac death (SCD). We hypothesized that DNA variants within genes previously associated with schizophrenia and epilepsy may contribute to an increased risk of SCD.
Related JoVE Video
Effect of mood states and infertility stress on patients attitudes toward embryo transfer and multiple pregnancy.
Fertil. Steril.
PUBLISHED: 01-15-2013
Show Abstract
Hide Abstract
To examine whether mood state or infertility stress influences perceptions of risk, preferences for embryo transfer, or views on multiple pregnancy.
Related JoVE Video
Resequencing and clinical associations of the 9p21.3 region: a comprehensive investigation in the Framingham heart study.
Circulation
PUBLISHED: 01-11-2013
Show Abstract
Hide Abstract
9p21.3 is among the most strongly replicated regions for cardiovascular disease. There are few reports of sequencing the associated 9p21.3 interval. We set out to sequence the 9p21.3 region followed by a comprehensive study of genetic associations with clinical and subclinical cardiovascular disease and its risk factors, as well as with copy number variation and gene expression, in the Framingham Heart Study (FHS).
Related JoVE Video
Loci influencing blood pressure identified using a cardiovascular gene-centric array.
Santhi K Ganesh, Vinicius Tragante, Wei Guo, Yiran Guo, Matthew B Lanktree, Erin N Smith, Toby Johnson, Berta Almoguera Castillo, John Barnard, Jens Baumert, Yen-Pei Christy Chang, Clara C Elbers, Martin Farrall, Mary E Fischer, Nora Franceschini, Tom R Gaunt, Johannes M I H Gho, Christian Gieger, Yan Gong, Aaron Isaacs, Marcus E Kleber, Irene Mateo Leach, Caitrin W McDonough, Matthijs F L Meijs, Olle Mellander, Cliona M Molony, Ilja M Nolte, Sandosh Padmanabhan, Tom S Price, Ramakrishnan Rajagopalan, Jonathan Shaffer, Sonia Shah, Haiqing Shen, Nicole Soranzo, Peter J van der Most, Erik P A van Iperen, Jessica van Setten, Jessic A Van Setten, Judith M Vonk, Li Zhang, Amber L Beitelshees, Gerald S Berenson, Deepak L Bhatt, Jolanda M A Boer, Eric Boerwinkle, Ben Burkley, Amber Burt, Aravinda Chakravarti, Wei Chen, Rhonda M Cooper-DeHoff, Sean P Curtis, Albert Dreisbach, David Duggan, Georg B Ehret, Richard R Fabsitz, Myriam Fornage, Ervin Fox, Clement E Furlong, Ron T Gansevoort, Marten H Hofker, G Kees Hovingh, Susan A Kirkland, Kandice Kottke-Marchant, Abdullah Kutlar, Andrea Z LaCroix, Taimour Y Langaee, Yun R Li, Honghuang Lin, Kiang Liu, Steffi Maiwald, Rainer Malik, , Gurunathan Murugesan, Christopher Newton-Cheh, Jeffery R O'Connell, N Charlotte Onland-Moret, Willem H Ouwehand, Walter Palmas, Brenda W Penninx, Carl J Pepine, Mary Pettinger, Joseph F Polak, Vasan S Ramachandran, Jane Ranchalis, Susan Redline, Paul M Ridker, Lynda M Rose, Hubert Scharnag, Nicholas J Schork, Daichi Shimbo, Alan R Shuldiner, Sathanur R Srinivasan, Ronald P Stolk, Herman A Taylor, Barbara Thorand, Mieke D Trip, Cornelia M van Duijn, W Monique Verschuren, Cisca Wijmenga, Bernhard R Winkelmann, Sharon Wyatt, J Hunter Young, Bernhard O Boehm, Mark J Caulfield, Daniel I Chasman, Karina W Davidson, Pieter A Doevendans, Garret A FitzGerald, John G Gums, Hakon Hakonarson, Hans L Hillege, Thomas Illig, Gail P Jarvik, Julie A Johnson, John J P Kastelein, Wolfgang Koenig, Winfried März, Braxton D Mitchell, Sarah S Murray, Albertine J Oldehinkel, Daniel J Rader, Muredach P Reilly, Alex P Reiner, Eric E Schadt, Roy L Silverstein, Harold Snieder, Alice V Stanton, André G Uitterlinden, Pim van der Harst, Yvonne T van der Schouw, Nilesh J Samani, Andrew D Johnson, Patricia B Munroe, Paul I W de Bakker, Xiaofeng Zhu, Daniel Levy, Brendan J Keating, Folkert W Asselbergs.
Hum. Mol. Genet.
PUBLISHED: 01-08-2013
Show Abstract
Hide Abstract
Blood pressure (BP) is a heritable determinant of risk for cardiovascular disease (CVD). To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP), we genotyped ?50 000 single-nucleotide polymorphisms (SNPs) that capture variation in ?2100 candidate genes for cardiovascular phenotypes in 61 619 individuals of European ancestry from cohort studies in the USA and Europe. We identified novel associations between rs347591 and SBP (chromosome 3p25.3, in an intron of HRH1) and between rs2169137 and DBP (chromosome1q32.1 in an intron of MDM4) and between rs2014408 and SBP (chromosome 11p15 in an intron of SOX6), previously reported to be associated with MAP. We also confirmed 10 previously known loci associated with SBP, DBP, MAP or PP (ADRB1, ATP2B1, SH2B3/ATXN2, CSK, CYP17A1, FURIN, HFE, LSP1, MTHFR, SOX6) at array-wide significance (P < 2.4 × 10(-6)). We then replicated these associations in an independent set of 65 886 individuals of European ancestry. The findings from expression QTL (eQTL) analysis showed associations of SNPs in the MDM4 region with MDM4 expression. We did not find any evidence of association of the two novel SNPs in MDM4 and HRH1 with sequelae of high BP including coronary artery disease (CAD), left ventricular hypertrophy (LVH) or stroke. In summary, we identified two novel loci associated with BP and confirmed multiple previously reported associations. Our findings extend our understanding of genes involved in BP regulation, some of which may eventually provide new targets for therapeutic intervention.
Related JoVE Video
Minimizing unnecessary parenteral nutrition after appendectomy in children.
J. Surg. Res.
PUBLISHED: 01-05-2013
Show Abstract
Hide Abstract
Consensus guidelines have indicated that postoperative parenteral nutrition (PN) might provide benefit when patients are expected to be nil per os (NPO) ?7 d and when PN is administered ?5 d. We hypothesized that most children receiving PN after appendectomy do not satisfy these criteria.
Related JoVE Video
Novel loci associated with increased risk of sudden cardiac death in the context of coronary artery disease.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Recent genome-wide association studies (GWAS) have identified novel loci associated with sudden cardiac death (SCD). Despite this progress, identified DNA variants account for a relatively small portion of overall SCD risk, suggesting that additional loci contributing to SCD susceptibility await discovery. The objective of this study was to identify novel DNA variation associated with SCD in the context of coronary artery disease (CAD).
Related JoVE Video
Low plasma level of atrial natriuretic peptide predicts development of diabetes: the prospective Malmo Diet and Cancer study.
J. Clin. Endocrinol. Metab.
PUBLISHED: 11-23-2011
Show Abstract
Hide Abstract
The cardiac natriuretic peptides are involved in blood pressure regulation, and large cross-sectional studies have shown lower plasma levels of N-terminal pro-natriuretic peptide levels [N-terminal atrial natriuretic peptide (N-ANP) and N-terminal brain natriuretic peptide (N-BNP)] in patients with insulin resistance, obesity, and diabetes.
Related JoVE Video
Fc receptor-like 5 promotes B cell proliferation and drives the development of cells displaying switched isotypes.
J. Leukoc. Biol.
PUBLISHED: 10-25-2011
Show Abstract
Hide Abstract
The biological roles of B cell membrane proteins in the FCRL family are enigmatic. FCRL proteins, including FCRL5, were shown to modulate early BCR signaling, although the subsequent, functional consequences of receptor engagement are poorly understood. We found that FCRL5 surface protein itself was induced temporarily upon BCR stimulation of human, naive B cells, indicating precise control over timing of FCRL5 engagement. Cross-linking of FCRL5 on cells induced to express FCRL5 enhanced B cell proliferation significantly. This enhancement required costimulation of the BCR and TLR9, two signals required for optimal proliferation of naive B cells, whereas T cell help in the form of anti-CD40 and IL-2 was dispensable. In addition, we found that FCRL5 stimulation generated a high proportion of cells displaying surface IgG and IgA. Optimal development of cells expressing switched isotypes required T cell help, in addition to stimuli found necessary for enhanced proliferation. Surprisingly, cells that developed upon FCRL5 stimulation simultaneously displayed surface IgM, IgG, and IgA. Cells expressing multiple Ig isotypes were described in hairy cell leukemia, a disease in which FCRL5 is overexpressed. Enhanced proliferation and downstream isotype expression upon FCRL5 stimulation could reflect a physiological role for FCRL5 in the expansion and development of antigen-primed B cells. In addition, FCRL5 may promote growth of malignant cells in hairy cell leukemia and other FCRL5-expressing tumors.
Related JoVE Video
Genetic variants and blood pressure in a population-based cohort: the Cardiovascular Risk in Young Finns study.
Hypertension
PUBLISHED: 10-24-2011
Show Abstract
Hide Abstract
Clinical relevance of a genetic predisposition to elevated blood pressure was quantified during the transition from childhood to adulthood in a population-based Finnish cohort (N=2357). Blood pressure was measured at baseline in 1980 (age 3-18 years) and in follow-ups in 1983, 1986, 2001, and 2007. Thirteen single nucleotide polymorphisms associated with blood pressure were genotyped, and 3 genetic risk scores associated with systolic and diastolic blood pressures and their combination were derived for all of the participants. Effects of the genetic risk score were 0.47 mm Hg for systolic and 0.53 mm Hg for diastolic blood pressures (both P<0.01). The combination genetic risk score was associated with diastolic blood pressure from age 9 years onward (?=0.68 mm Hg; P=0.015). Replications in 1194 participants of the Bogalusa Heart Study showed essentially similar results. The participants in the highest quintile of the combination genetic risk score had a 1.82-fold risk of hypertension in adulthood (P<0.0001) compared with the lowest quintile, independent of a family history of premature hypertension. These findings show that genetic variants are associated with preclinical blood pressure traits in childhood; individuals with several susceptibility alleles have, on average, a 0.5-mm Hg higher blood pressure, and this trajectory continues from childhood to adulthood.
Related JoVE Video
Cardiac natriuretic peptides, obesity, and insulin resistance: evidence from two community-based studies.
J. Clin. Endocrinol. Metab.
PUBLISHED: 08-17-2011
Show Abstract
Hide Abstract
The natriuretic peptides play an important role in salt homeostasis and blood pressure regulation. It has been suggested that obesity promotes a relative natriuretic peptide deficiency, but this has been a variable finding in prior studies and the cause is unknown.
Related JoVE Video
Substitution of standard soybean oil with olive oil-based lipid emulsion in parenteral nutrition: comparison of vascular, metabolic, and inflammatory effects.
J. Clin. Endocrinol. Metab.
PUBLISHED: 08-10-2011
Show Abstract
Hide Abstract
Soybean oil-based lipid emulsions are the only Food and Drug Administration-approved lipid formulation for clinical use in parenteral nutrition (PN). Recently concerns with its use have been raised due to the proinflammatory effects that may lead to increased complications because they are rich in ?-6 polyunsaturated fatty acids.
Related JoVE Video
Genetic variants in novel pathways influence blood pressure and cardiovascular disease risk.
, Georg B Ehret, Patricia B Munroe, Kenneth M Rice, Murielle Bochud, Andrew D Johnson, Daniel I Chasman, Albert V Smith, Martin D Tobin, Germaine C Verwoert, Shih-Jen Hwang, Vasyl Pihur, Peter Vollenweider, Paul F O'Reilly, Najaf Amin, Jennifer L Bragg-Gresham, Alexander Teumer, Nicole L Glazer, Lenore Launer, Jing Hua Zhao, Yurii Aulchenko, Simon Heath, Siim Sõber, Afshin Parsa, Jian'an Luan, Pankaj Arora, Abbas Dehghan, Feng Zhang, Gavin Lucas, Andrew A Hicks, Anne U Jackson, John F Peden, Toshiko Tanaka, Sarah H Wild, Igor Rudan, Wilmar Igl, Yuri Milaneschi, Alex N Parker, Cristiano Fava, John C Chambers, Ervin R Fox, Meena Kumari, Min Jin Go, Pim van der Harst, Wen Hong Linda Kao, Marketa Sjögren, D G Vinay, Myriam Alexander, Yasuharu Tabara, Sue Shaw-Hawkins, Peter H Whincup, Yongmei Liu, Gang Shi, Johanna Kuusisto, Bamidele Tayo, Mark Seielstad, Xueling Sim, Khanh-Dung Hoang Nguyen, Terho Lehtimäki, Giuseppe Matullo, Ying Wu, Tom R Gaunt, N Charlotte Onland-Moret, Matthew N Cooper, Carl G P Platou, Elin Org, Rebecca Hardy, Santosh Dahgam, Jutta Palmen, Veronique Vitart, Peter S Braund, Tatiana Kuznetsova, Cuno S P M Uiterwaal, Adebowale Adeyemo, Walter Palmas, Harry Campbell, Barbara Ludwig, Maciej Tomaszewski, Ioanna Tzoulaki, Nicholette D Palmer, Thor Aspelund, Melissa Garcia, Yen-Pei C Chang, Jeffrey R O'Connell, Nanette I Steinle, Diederick E Grobbee, Dan E Arking, Sharon L Kardia, Alanna C Morrison, Dena Hernandez, Samer Najjar, Wendy L McArdle, David Hadley, Morris J Brown, John M Connell, Aroon D Hingorani, Ian N M Day, Debbie A Lawlor, John P Beilby, Robert W Lawrence, Robert Clarke, Jemma C Hopewell, Halit Ongen, Albert W Dreisbach, Yali Li, J Hunter Young, Joshua C Bis, Mika Kähönen, Jorma Viikari, Linda S Adair, Nanette R Lee, Ming-Huei Chen, Matthias Olden, Cristian Pattaro, Judith A Hoffman Bolton, Anna Köttgen, Sven Bergmann, Vincent Mooser, Nish Chaturvedi, Timothy M Frayling, Muhammad Islam, Tazeen H Jafar, Jeanette Erdmann, Smita R Kulkarni, Stefan R Bornstein, Jürgen Gräßler, Leif Groop, Benjamin F Voight, Johannes Kettunen, Philip Howard, Andrew Taylor, Simonetta Guarrera, Fulvio Ricceri, Valur Emilsson, Andrew Plump, Inês Barroso, Kay-Tee Khaw, Alan B Weder, Steven C Hunt, Yan V Sun, Richard N Bergman, Francis S Collins, Lori L Bonnycastle, Laura J Scott, Heather M Stringham, Leena Peltonen, Markus Perola, Erkki Vartiainen, Stefan-Martin Brand, Jan A Staessen, Thomas J Wang, Paul R Burton, María Soler Artigas, Yanbin Dong, Harold Snieder, Xiaoling Wang, Haidong Zhu, Kurt K Lohman, Megan E Rudock, Susan R Heckbert, Nicholas L Smith, Kerri L Wiggins, Ayo Doumatey, Daniel Shriner, Gudrun Veldre, Margus Viigimaa, Sanjay Kinra, Dorairaj Prabhakaran, Vikal Tripathy, Carl D Langefeld, Annika Rosengren, Dag S Thelle, Anna Maria Corsi, Andrew Singleton, Terrence Forrester, Gina Hilton, Colin A McKenzie, Tunde Salako, Naoharu Iwai, Yoshikuni Kita, Toshio Ogihara, Takayoshi Ohkubo, Tomonori Okamura, Hirotsugu Ueshima, Satoshi Umemura, Susana Eyheramendy, Thomas Meitinger, H-Erich Wichmann, Yoon Shin Cho, Hyung-Lae Kim, Jong-Young Lee, James Scott, Joban S Sehmi, Weihua Zhang, Bo Hedblad, Peter Nilsson, George Davey Smith, Andrew Wong, Narisu Narisu, Alena Stančáková, Leslie J Raffel, Jie Yao, Sekar Kathiresan, Christopher J O'Donnell, Stephen M Schwartz, M Arfan Ikram, W T Longstreth, Thomas H Mosley, Sudha Seshadri, Nick R G Shrine, Louise V Wain, Mario A Morken, Amy J Swift, Jaana Laitinen, Inga Prokopenko, Paavo Zitting, Jackie A Cooper, Steve E Humphries, John Danesh, Asif Rasheed, Anuj Goel, Anders Hamsten, Hugh Watkins, Stephan J L Bakker, Wiek H van Gilst, Charles S Janipalli, K Radha Mani, Chittaranjan S Yajnik, Albert Hofman, Francesco U S Mattace-Raso, Ben A Oostra, Ayse Demirkan, Aaron Isaacs, Fernando Rivadeneira, Edward G Lakatta, Marco Orrù, Angelo Scuteri, Mika Ala-Korpela, Antti J Kangas, Leo-Pekka Lyytikäinen, Pasi Soininen, Taru Tukiainen, Peter Würtz, Rick Twee-Hee Ong, Marcus Dörr, Heyo K Kroemer, Uwe Völker, Henry Völzke, Pilar Galán, Serge Hercberg, Mark Lathrop, Diana Zelenika, Panos Deloukas, Massimo Mangino, Tim D Spector, Guangju Zhai, James F Meschia, Michael A Nalls, Pankaj Sharma, Janos Terzic, M V Kranthi Kumar, Matthew Denniff, Ewa Zukowska-Szczechowska, Lynne E Wagenknecht, F Gerald R Fowkes, Fadi J Charchar, Peter E H Schwarz, Caroline Hayward, Xiuqing Guo, Charles Rotimi, Michiel L Bots, Eva Brand, Nilesh J Samani, Ozren Polašek, Philippa J Talmud, Fredrik Nyberg, Diana Kuh, Maris Laan, Kristian Hveem, Lyle J Palmer, Yvonne T van der Schouw, Juan P Casas, Karen L Mohlke, Paolo Vineis, Olli Raitakari, Santhi K Ganesh, Tien Y Wong, E Shyong Tai, Richard S Cooper, Markku Laakso, Dabeeru C Rao, Tamara B Harris, Richard W Morris, Anna F Dominiczak, Mika Kivimäki, Michael G Marmot, Tetsuro Miki, Danish Saleheen, Giriraj R Chandak, Josef Coresh, Gerjan Navis, Veikko Salomaa, Bok-Ghee Han, Xiaofeng Zhu, Jaspal S Kooner, Olle Melander, Paul M Ridker, Stefania Bandinelli, Ulf B Gyllensten, Alan F Wright, James F Wilson, Luigi Ferrucci, Martin Farrall, Jaakko Tuomilehto, Peter P Pramstaller, Roberto Elosua, Nicole Soranzo, Eric J G Sijbrands, David Altshuler, Ruth J F Loos, Alan R Shuldiner, Christian Gieger, Pierre Meneton, André G Uitterlinden, Nicholas J Wareham, Vilmundur Gudnason, Jerome I Rotter, Rainer Rettig, Manuela Uda, David P Strachan, Jacqueline C M Witteman, Anna-Liisa Hartikainen, Jacques S Beckmann, Eric Boerwinkle, Ramachandran S Vasan, Michael Boehnke, Martin G Larson, Marjo-Riitta Järvelin, Bruce M Psaty, Gonçalo R Abecasis, Aravinda Chakravarti, Paul Elliott, Cornelia M van Duijn, Christopher Newton-Cheh, Daniel Levy, Mark J Caulfield, Toby Johnson.
Nature
PUBLISHED: 07-28-2011
Show Abstract
Hide Abstract
Blood pressure is a heritable trait influenced by several biological pathways and responsive to environmental stimuli. Over one billion people worldwide have hypertension (?140?mm?Hg systolic blood pressure or? ?90?mm?Hg diastolic blood pressure). Even small increments in blood pressure are associated with an increased risk of cardiovascular events. This genome-wide association study of systolic and diastolic blood pressure, which used a multi-stage design in 200,000 individuals of European descent, identified sixteen novel loci: six of these loci contain genes previously known or suspected to regulate blood pressure (GUCY1A3-GUCY1B3, NPR3-C5orf23, ADM, FURIN-FES, GOSR2, GNAS-EDN3); the other ten provide new clues to blood pressure physiology. A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function. We also observed associations with blood pressure in East Asian, South Asian and African ancestry individuals. Our findings provide new insights into the genetics and biology of blood pressure, and suggest potential novel therapeutic pathways for cardiovascular disease prevention.
Related JoVE Video
Effects of transdermal testosterone on natriuretic peptide levels in women: a randomized placebo-controlled pilot study.
Fertil. Steril.
PUBLISHED: 07-25-2011
Show Abstract
Hide Abstract
To investigate whether testosterone administration alters natriuretic peptide levels in women.
Related JoVE Video
Blood pressure loci identified with a gene-centric array.
Toby Johnson, Tom R Gaunt, Stephen J Newhouse, Sandosh Padmanabhan, Maciej Tomaszewski, Meena Kumari, Richard W Morris, Ioanna Tzoulaki, Eoin T O'Brien, Neil R Poulter, Peter Sever, Denis C Shields, Simon Thom, Sasiwarang G Wannamethee, Peter H Whincup, Morris J Brown, John M Connell, Richard J Dobson, Philip J Howard, Charles A Mein, Abiodun Onipinla, Sue Shaw-Hawkins, Yun Zhang, George Davey Smith, Ian N M Day, Debbie A Lawlor, Alison H Goodall, , F Gerald Fowkes, Gonçalo R Abecasis, Paul Elliott, Vesela Gateva, Peter S Braund, Paul R Burton, Christopher P Nelson, Martin D Tobin, Pim van der Harst, Nicola Glorioso, Hani Neuvrith, Erika Salvi, Jan A Staessen, Andrea Stucchi, Nabila Devos, Xavier Jeunemaitre, Pierre-Francois Plouin, Jean Tichet, Peeter Juhanson, Elin Org, Margus Putku, Siim Sõber, Gudrun Veldre, Margus Viigimaa, Anna Levinsson, Annika Rosengren, Dag S Thelle, Claire E Hastie, Thomas Hedner, Wai K Lee, Olle Melander, Björn Wahlstrand, Rebecca Hardy, Andrew Wong, Jackie A Cooper, Jutta Palmen, Li Chen, Alexandre F R Stewart, George A Wells, Harm-Jan Westra, Marcel G M Wolfs, Robert Clarke, Maria Grazia Franzosi, Anuj Goel, Anders Hamsten, Mark Lathrop, John F Peden, Udo Seedorf, Hugh Watkins, Willem H Ouwehand, Jennifer Sambrook, Jonathan Stephens, Juan-Pablo Casas, Fotios Drenos, Michael V Holmes, Mika Kivimäki, Sonia Shah, Tina Shah, Philippa J Talmud, John Whittaker, Chris Wallace, Christian Delles, Maris Laan, Diana Kuh, Steve E Humphries, Fredrik Nyberg, Daniele Cusi, Robert Roberts, Christopher Newton-Cheh, Lude Franke, Alice V Stanton, Anna F Dominiczak, Martin Farrall, Aroon D Hingorani, Nilesh J Samani, Mark J Caulfield, Patricia B Munroe.
Am. J. Hum. Genet.
PUBLISHED: 06-15-2011
Show Abstract
Hide Abstract
Raised blood pressure (BP) is a major risk factor for cardiovascular disease. Previous studies have identified 47 distinct genetic variants robustly associated with BP, but collectively these explain only a few percent of the heritability for BP phenotypes. To find additional BP loci, we used a bespoke gene-centric array to genotype an independent discovery sample of 25,118 individuals that combined hypertensive case-control and general population samples. We followed up four SNPs associated with BP at our p < 8.56 × 10(-7) study-specific significance threshold and six suggestively associated SNPs in a further 59,349 individuals. We identified and replicated a SNP at LSP1/TNNT3, a SNP at MTHFR-NPPB independent (r(2) = 0.33) of previous reports, and replicated SNPs at AGT and ATP2B1 reported previously. An analysis of combined discovery and follow-up data identified SNPs significantly associated with BP at p < 8.56 × 10(-7) at four further loci (NPR3, HFE, NOS3, and SOX6). The high number of discoveries made with modest genotyping effort can be attributed to using a large-scale yet targeted genotyping array and to the development of a weighting scheme that maximized power when meta-analyzing results from samples ascertained with extreme phenotypes, in combination with results from nonascertained or population samples. Chromatin immunoprecipitation and transcript expression data highlight potential gene regulatory mechanisms at the MTHFR and NOS3 loci. These results provide candidates for further study to help dissect mechanisms affecting BP and highlight the utility of studying SNPs and samples that are independent of those studied previously even when the sample size is smaller than that in previous studies.
Related JoVE Video
Early repolarization pattern in competitive athletes: clinical correlates and the effects of exercise training.
Circ Arrhythm Electrophysiol
PUBLISHED: 05-04-2011
Show Abstract
Hide Abstract
Inferior lead early repolarization pattern (ERP) recently has been associated with sudden cardiac death. Although ERP is common among athletes, prevalence, ECG lead distribution, clinical characteristics, and effects of physical training remain uncertain. We sought to examine the nonanterior ERP in competitive athletes.
Related JoVE Video
Common genetic variants, QT interval, and sudden cardiac death in a Finnish population-based study.
Circ Cardiovasc Genet
PUBLISHED: 04-21-2011
Show Abstract
Hide Abstract
Although sudden cardiac death (SCD) is heritable, its genetic underpinnings are poorly characterized. The QT interval appears to have a graded relationship to SCD, and 35% to 45% of its variation is heritable. We examined the relationship among recently reported common genetic variants, QT interval, and SCD.
Related JoVE Video
Association of hypertension drug target genes with blood pressure and hypertension in 86,588 individuals.
Hypertension
PUBLISHED: 03-28-2011
Show Abstract
Hide Abstract
We previously conducted genome-wide association meta-analysis of systolic blood pressure, diastolic blood pressure, and hypertension in 29,136 people from 6 cohort studies in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Here we examine associations of these traits with 30 gene regions encoding known antihypertensive drug targets. We find nominal evidence of association of ADRB1, ADRB2, AGT, CACNA1A, CACNA1C, and SLC12A3 polymorphisms with 1 or more BP traits in the Cohorts for Heart and Aging Research in Genomic Epidemiology genome-wide association meta-analysis. We attempted replication of the top meta-analysis single nucleotide polymorphisms for these genes in the Global BPgen Consortium (n=34,433) and the Womens Genome Health Study (n=23,019) and found significant results for rs1801253 in ADRB1 (Arg389Gly), with the Gly allele associated with a lower mean systolic blood pressure (?: 0.57 mm Hg; SE: 0.09 mm Hg; meta-analysis: P=4.7×10(-10)), diastolic blood pressure (?: 0.36 mm Hg; SE: 0.06 mm Hg; meta-analysis: P=9.5×10(-10)), and prevalence of hypertension (?: 0.06 mm Hg; SE: 0.02 mm Hg; meta-analysis: P=3.3×10(-4)). Variation in AGT (rs2004776) was associated with systolic blood pressure (?: 0.42 mm Hg; SE: 0.09 mm Hg; meta-analysis: P=3.8×10(-6)), as well as diastolic blood pressure (P=5.0×10(-8)) and hypertension (P=3.7×10(-7)). A polymorphism in ACE (rs4305) showed modest replication of association with increased hypertension (?: 0.06 mm Hg; SE: 0.01 mm Hg; meta-analysis: P=3.0×10(-5)). Two loci, ADRB1 and AGT, contain single nucleotide polymorphisms that reached a genome-wide significance threshold in meta-analysis for the first time. Our findings suggest that these genes warrant further studies of their genetic effects on blood pressure, including pharmacogenetic interactions.
Related JoVE Video
Relation of visceral adiposity to circulating natriuretic peptides in ambulatory individuals.
Am. J. Cardiol.
PUBLISHED: 03-23-2011
Show Abstract
Hide Abstract
Natriuretic peptides have important roles in the regulation of vasomotor tone, salt homeostasis, and ventricular remodeling. Lower natriuretic peptide levels observed in obese individuals may underlie the greater cardiovascular risk associated with obesity. Thus the aim of this study was to determine whether lower natriuretic peptide levels in obesity are attributable to differences in regional fat distribution. We investigated the relation of plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) to regional adiposity in 1,873 community-based individuals (46% women, mean age 45 years). Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) volumes were measured by multidetector computed tomography. In gender-specific multivariable analyses adjusting for age and blood pressure, log NT-pro-BNP was inversely associated with VAT in men (beta -0.11 per standard deviation increment, p <0.001) and women (beta -0.19, p <0.001). Log NT-pro-BNP was inversely associated with SAT in women only (beta -0.14, p <0.001). In models containing VAT and SAT, only VAT was significantly associated with log NT-pro-BNP (men, beta -0.137, p <0.001; women, beta -0.184, p <0.001). VAT remained associated with log NT-pro-BNP even after adjustment for body mass index and waist circumference (beta -0.119, p <0.001) and in analyses restricted to nonobese patients (beta -0.165, p <0.001). Adjustment for insulin resistance attenuated the associations of NT-pro-BNP with VAT and SAT. In conclusion, this study demonstrates that circulating NT-pro-BNP is related to variations in regional and particularly visceral adiposity. These findings suggest that excess visceral adiposity and concomitant hyperinsulinemia may contribute to the natriuretic peptide "deficiency" observed in obesity.
Related JoVE Video
Combined admixture mapping and association analysis identifies a novel blood pressure genetic locus on 5p13: contributions from the CARe consortium.
Hum. Mol. Genet.
PUBLISHED: 03-21-2011
Show Abstract
Hide Abstract
Admixture mapping based on recently admixed populations is a powerful method to detect disease variants with substantial allele frequency differences in ancestral populations. We performed admixture mapping analysis for systolic blood pressure (SBP) and diastolic blood pressure (DBP), followed by trait-marker association analysis, in 6303 unrelated African-American participants of the Candidate Gene Association Resource (CARe) consortium. We identified five genomic regions (P< 0.001) harboring genetic variants contributing to inter-individual BP variation. In follow-up association analyses, correcting for all tests performed in this study, three loci were significantly associated with SBP and one significantly associated with DBP (P< 10(-5)). Further analyses suggested that six independent single-nucleotide polymorphisms (SNPs) contributed to the phenotypic variation observed in the admixture mapping analysis. These six SNPs were examined for replication in multiple, large, independent studies of African-Americans [Womens Health Initiative (WHI), Maywood, Genetic Epidemiology Network of Arteriopathy (GENOA) and Howard University Family Study (HUFS)] as well as one native African sample (Nigerian study), with a total replication sample size of 11 882. Meta-analysis of the replication set identified a novel variant (rs7726475) on chromosome 5 between the SUB1 and NPR3 genes, as being associated with SBP and DBP (P< 0.0015 for both); in meta-analyses combining the CARe samples with the replication data, we observed P-values of 4.45 × 10(-7) for SBP and 7.52 × 10(-7) for DBP for rs7726475 that were significant after accounting for all the tests performed. Our study highlights that admixture mapping analysis can help identify genetic variants missed by genome-wide association studies because of drastically reduced number of tests in the whole genome.
Related JoVE Video
Influence of sex and hormone status on circulating natriuretic peptides.
J. Am. Coll. Cardiol.
PUBLISHED: 03-15-2011
Show Abstract
Hide Abstract
The aim of this study was to assess the relationship between sex hormones and natriuretic peptide levels in community-based adults.
Related JoVE Video
The early repolarization pattern in the general population: clinical correlates and heritability.
J. Am. Coll. Cardiol.
PUBLISHED: 03-04-2011
Show Abstract
Hide Abstract
This study sought to describe the clinical correlates and heritability of the early repolarization pattern (ERP) in 2 large, population-based cohorts.
Related JoVE Video
Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure.
Louise V Wain, Germaine C Verwoert, Paul F O'Reilly, Gang Shi, Toby Johnson, Andrew D Johnson, Murielle Bochud, Kenneth M Rice, Peter Henneman, Albert V Smith, Georg B Ehret, Najaf Amin, Martin G Larson, Vincent Mooser, David Hadley, Marcus Dörr, Joshua C Bis, Thor Aspelund, Tonu Esko, A Cecile J W Janssens, Jing Hua Zhao, Simon Heath, Maris Laan, Jingyuan Fu, Giorgio Pistis, Jian'an Luan, Pankaj Arora, Gavin Lucas, Nicola Pirastu, Irene Pichler, Anne U Jackson, Rebecca J Webster, Feng Zhang, John F Peden, Helena Schmidt, Toshiko Tanaka, Harry Campbell, Wilmar Igl, Yuri Milaneschi, Jouke-Jan Hottenga, Veronique Vitart, Daniel I Chasman, Stella Trompet, Jennifer L Bragg-Gresham, Behrooz Z Alizadeh, John C Chambers, Xiuqing Guo, Terho Lehtimäki, Brigitte Kühnel, Lorna M Lopez, Ozren Polašek, Mladen Boban, Christopher P Nelson, Alanna C Morrison, Vasyl Pihur, Santhi K Ganesh, Albert Hofman, Suman Kundu, Francesco U S Mattace-Raso, Fernando Rivadeneira, Eric J G Sijbrands, André G Uitterlinden, Shih-Jen Hwang, Ramachandran S Vasan, Thomas J Wang, Sven Bergmann, Peter Vollenweider, Gérard Waeber, Jaana Laitinen, Anneli Pouta, Paavo Zitting, Wendy L McArdle, Heyo K Kroemer, Uwe Völker, Henry Völzke, Nicole L Glazer, Kent D Taylor, Tamara B Harris, Helene Alavere, Toomas Haller, Aime Keis, Mari-Liis Tammesoo, Yurii Aulchenko, Inês Barroso, Kay-Tee Khaw, Pilar Galán, Serge Hercberg, Mark Lathrop, Susana Eyheramendy, Elin Org, Siim Sõber, Xiaowen Lu, Ilja M Nolte, Brenda W Penninx, Tanguy Corre, Corrado Masciullo, Cinzia Sala, Leif Groop, Benjamin F Voight, Olle Melander, Christopher J O'Donnell, Veikko Salomaa, Adamo Pio D'adamo, Antonella Fabretto, Flavio Faletra, Sheila Ulivi, Fabiola M Del Greco, Maurizio Facheris, Francis S Collins, Richard N Bergman, John P Beilby, Joseph Hung, A William Musk, Massimo Mangino, So-Youn Shin, Nicole Soranzo, Hugh Watkins, Anuj Goel, Anders Hamsten, Pierre Gider, Marisa Loitfelder, Marion Zeginigg, Dena Hernandez, Samer S Najjar, Pau Navarro, Sarah H Wild, Anna Maria Corsi, Andrew Singleton, Eco J C de Geus, Gonneke Willemsen, Alex N Parker, Lynda M Rose, Brendan Buckley, David Stott, Marco Orrù, Manuela Uda, , Melanie M van der Klauw, Weihua Zhang, Xinzhong Li, James Scott, Yii-Der Ida Chen, Gregory L Burke, Mika Kähönen, Jorma Viikari, Angela Döring, Thomas Meitinger, Gail Davies, John M Starr, Valur Emilsson, Andrew Plump, Jan H Lindeman, Peter A C 't Hoen, Inke R König, Janine F Felix, Robert Clarke, Jemma C Hopewell, Halit Ongen, Monique Breteler, Stéphanie Debette, Anita L Destefano, Myriam Fornage, Gary F Mitchell, Nicholas L Smith, Hilma Holm, Kari Stefansson, Gudmar Thorleifsson, Unnur Thorsteinsdottir, Nilesh J Samani, Michael Preuss, Igor Rudan, Caroline Hayward, Ian J Deary, H-Erich Wichmann, Olli T Raitakari, Walter Palmas, Jaspal S Kooner, Ronald P Stolk, J Wouter Jukema, Alan F Wright, Dorret I Boomsma, Stefania Bandinelli, Ulf B Gyllensten, James F Wilson, Luigi Ferrucci, Reinhold Schmidt, Martin Farrall, Tim D Spector, Lyle J Palmer, Jaakko Tuomilehto, Arne Pfeufer, Paolo Gasparini, David Siscovick, David Altshuler, Ruth J F Loos, Daniela Toniolo, Harold Snieder, Christian Gieger, Pierre Meneton, Nicholas J Wareham, Ben A Oostra, Andres Metspalu, Lenore Launer, Rainer Rettig, David P Strachan, Jacques S Beckmann, Jacqueline C M Witteman, Jeanette Erdmann, Ko Willems van Dijk, Eric Boerwinkle, Michael Boehnke, Paul M Ridker, Marjo-Riitta Järvelin, Aravinda Chakravarti, Gonçalo R Abecasis, Vilmundur Gudnason, Christopher Newton-Cheh, Daniel Levy, Patricia B Munroe, Bruce M Psaty, Mark J Caulfield, Dabeeru C Rao, Martin D Tobin, Paul Elliott, Cornelia M van Duijn.
Nat. Genet.
PUBLISHED: 02-10-2011
Show Abstract
Hide Abstract
Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we identified at genome-wide significance (P = 2.7 × 10(-8) to P = 2.3 × 10(-13)) four new PP loci (at 4q12 near CHIC2, 7q22.3 near PIK3CG, 8q24.12 in NOV and 11q24.3 near ADAMTS8), two new MAP loci (3p21.31 in MAP4 and 10q25.3 near ADRB1) and one locus associated with both of these traits (2q24.3 near FIGN) that has also recently been associated with SBP in east Asians. For three of the new PP loci, the estimated effect for SBP was opposite of that for DBP, in contrast to the majority of common SBP- and DBP-associated variants, which show concordant effects on both traits. These findings suggest new genetic pathways underlying blood pressure variation, some of which may differentially influence SBP and DBP.
Related JoVE Video
Identification of a sudden cardiac death susceptibility locus at 2q24.2 through genome-wide association in European ancestry individuals.
PLoS Genet.
PUBLISHED: 01-29-2011
Show Abstract
Hide Abstract
Sudden cardiac death (SCD) continues to be one of the leading causes of mortality worldwide, with an annual incidence estimated at 250,000-300,000 in the United States and with the vast majority occurring in the setting of coronary disease. We performed a genome-wide association meta-analysis in 1,283 SCD cases and >20,000 control individuals of European ancestry from 5 studies, with follow-up genotyping in up to 3,119 SCD cases and 11,146 controls from 11 European ancestry studies, and identify the BAZ2B locus as associated with SCD (P?=?1.8×10(-10)). The risk allele, while ancestral, has a frequency of ~1.4%, suggesting strong negative selection and increases risk for SCD by 1.92-fold per allele (95% CI 1.57-2.34). We also tested the role of 49 SNPs previously implicated in modulating electrocardiographic traits (QRS, QT, and RR intervals). Consistent with epidemiological studies showing increased risk of SCD with prolonged QRS/QT intervals, the interval-prolonging alleles are in aggregate associated with increased risk for SCD (P?=?0.006).
Related JoVE Video
Association of genetic variation in the natriuretic peptide system with cardiovascular outcomes.
J. Mol. Cell. Cardiol.
PUBLISHED: 01-13-2011
Show Abstract
Hide Abstract
Polymorphisms within individual natriuretic peptide genes have been associated with risk factors for cardiovascular disease, but their association with clinical outcomes was previously unknown. This study aimed to investigate the association between genetic variants in key genes of the natriuretic peptide system with cardiovascular outcomes in patients with coronary artery disease. Coronary disease patients (n=1810) were genotyped for polymorphisms within NPPA, NPPB, NPPC, NPR1 and NPR2. Clinical history, natriuretic peptide concentrations, echocardiography, all-cause mortality and cardiovascular hospital readmissions were recorded over a median 2.8 years. Minor alleles of NPPA rs5068, rs5065 and rs198358 were associated with less history of hypertension; minor alleles of NPPA rs5068 and rs198358 was also associated with higher circulating natriuretic peptide levels (p=0.003 to p=0.04). Minor alleles of NPPB rs198388, rs198389, and rs632793 were associated with higher circulating BNP and NT-proBNP (p=0.001 to p=0.03), and reduced E/E(1) (p=0.011), or LVESVI (p=0.001) and LVEDVI (p=0.004). Within NPPC, both rs11079028 and rs479651 were associated with higher NT-proBNP and CNP (p=0.01 to p=0.03), and rs479651 was associated with lower LVESVI (p=0.008) and LVEDVI (p=0.018). NPR2 rs10758325 was associated with smaller LVMI (p<0.02). A reduced rate of cardiovascular readmission was observed for minor alleles of NPPA rs5065 (p<0.0001), NPPB rs632793 (p<0.0001), rs198388 (p<0.0001), rs198389 (p<0.0001), and NPR2 rs10758325 (p<0.0001). There were no associations with all-cause mortality. In established cardiovascular disease, natriuretic peptide system polymorphisms were associated with natriuretic peptide levels, hypertension, echocardiographic indices and the incidence of hospital readmission for cardiovascular events.
Related JoVE Video
Related JoVE Video
Genome-wide association studies of the PR interval in African Americans.
PLoS Genet.
PUBLISHED: 01-11-2011
Show Abstract
Hide Abstract
The PR interval on the electrocardiogram reflects atrial and atrioventricular nodal conduction time. The PR interval is heritable, provides important information about arrhythmia risk, and has been suggested to differ among human races. Genome-wide association (GWA) studies have identified common genetic determinants of the PR interval in individuals of European and Asian ancestry, but there is a general paucity of GWA studies in individuals of African ancestry. We performed GWA studies in African American individuals from four cohorts (n?=?6,247) to identify genetic variants associated with PR interval duration. Genotyping was performed using the Affymetrix 6.0 microarray. Imputation was performed for 2.8 million single nucleotide polymorphisms (SNPs) using combined YRI and CEU HapMap phase II panels. We observed a strong signal (rs3922844) within the gene encoding the cardiac sodium channel (SCN5A) with genome-wide significant association (p<2.5 x 10??) in two of the four cohorts and in the meta-analysis. The signal explained 2% of PR interval variability in African Americans (beta ?=?5.1 msec per minor allele, 95% CI ?=?4.1-6.1, p?=?3 x 10?²³). This SNP was also associated with PR interval (beta?=?2.4 msec per minor allele, 95% CI?=?1.8-3.0, p?=?3 x 10?¹?) in individuals of European ancestry (n?=?14,042), but with a smaller effect size (p for heterogeneity <0.001) and variability explained (0.5%). Further meta-analysis of the four cohorts identified genome-wide significant associations with SNPs in SCN10A (rs6798015), MEIS1 (rs10865355), and TBX5 (rs7312625) that were highly correlated with SNPs identified in European and Asian GWA studies. African ancestry was associated with increased PR duration (13.3 msec, p?=?0.009) in one but not the other three cohorts. Our findings demonstrate the relevance of common variants to African Americans at four loci previously associated with PR interval in European and Asian samples and identify an association signal at one of these loci that is more strongly associated with PR interval in African Americans than in Europeans.
Related JoVE Video
Genome-wide association study of coronary heart disease and its risk factors in 8,090 African Americans: the NHLBI CARe Project.
PLoS Genet.
PUBLISHED: 01-07-2011
Show Abstract
Hide Abstract
Coronary heart disease (CHD) is the leading cause of mortality in African Americans. To identify common genetic polymorphisms associated with CHD and its risk factors (LDL- and HDL-cholesterol (LDL-C and HDL-C), hypertension, smoking, and type-2 diabetes) in individuals of African ancestry, we performed a genome-wide association study (GWAS) in 8,090 African Americans from five population-based cohorts. We replicated 17 loci previously associated with CHD or its risk factors in Caucasians. For five of these regions (CHD: CDKN2A/CDKN2B; HDL-C: FADS1-3, PLTP, LPL, and ABCA1), we could leverage the distinct linkage disequilibrium (LD) patterns in African Americans to identify DNA polymorphisms more strongly associated with the phenotypes than the previously reported index SNPs found in Caucasian populations. We also developed a new approach for association testing in admixed populations that uses allelic and local ancestry variation. Using this method, we discovered several loci that would have been missed using the basic allelic and global ancestry information only. Our conclusions suggest that no major loci uniquely explain the high prevalence of CHD in African Americans. Our project has developed resources and methods that address both admixture- and SNP-association to maximize power for genetic discovery in even larger African-American consortia.
Related JoVE Video
A common variant in the ?2-adrenergic receptor and risk of sudden cardiac death.
Heart Rhythm
PUBLISHED: 01-02-2011
Show Abstract
Hide Abstract
Homozygosity for a common nonsynonymous single nucleotide polymorphism (Gln27Glu) in the ?(2)-adrenergic receptor gene (ADRB2) has been inconsistently associated with sudden cardiac death (SCD) in individual studies of small sample size.
Related JoVE Video
Increased power of mixed models facilitates association mapping of 10 loci for metabolic traits in an isolated population.
Hum. Mol. Genet.
PUBLISHED: 11-30-2010
Show Abstract
Hide Abstract
The potential benefits of using population isolates in genetic mapping, such as reduced genetic, phenotypic and environmental heterogeneity, are offset by the challenges posed by the large amounts of direct and cryptic relatedness in these populations confounding basic assumptions of independence. We have evaluated four representative specialized methods for association testing in the presence of relatedness; (i) within-family (ii) within- and between-family and (iii) mixed-models methods, using simulated traits for 2906 subjects with known genome-wide genotype data from an extremely isolated population, the Island of Kosrae, Federated States of Micronesia. We report that mixed models optimally extract association information from such samples, demonstrating 88% power to rank the true variant as among the top 10 genome-wide with 56% achieving genome-wide significance, a >80% improvement over the other methods, and demonstrate that population isolates have similar power to non-isolate populations for observing variants of known effects. We then used the mixed-model method to reanalyze data for 17 published phenotypes relating to metabolic traits and electrocardiographic measures, along with another 8 previously unreported. We replicate nine genome-wide significant associations with known loci of plasma cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, thyroid stimulating hormone, homocysteine, C-reactive protein and uric acid, with only one detected in the previous analysis of the same traits. Further, we leveraged shared identity-by-descent genetic segments in the region of the uric acid locus to fine-map the signal, refining the known locus by a factor of 4. Finally, we report a novel associations for height (rs17629022, P< 2.1 × 10??).
Related JoVE Video
A comparison study of continuous insulin infusion protocols in the medical intensive care unit: computer-guided vs. standard column-based algorithms.
J Hosp Med
PUBLISHED: 10-15-2010
Show Abstract
Hide Abstract
To compare the safety and efficacy of continuous insulin infusion (CII) via a computer-guided and a standard paper form protocol in a medical intensive care unit (ICU).
Related JoVE Video
The impact of continuous subcutaneous insulin infusion and multiple daily injections of insulin on glucose variability in older adults with type 2 diabetes.
J. Diabetes Complicat.
PUBLISHED: 09-13-2010
Show Abstract
Hide Abstract
To determine whether continuous subcutaneous insulin infusion (CSII) or multiple daily injections of insulin (MDI) are associated with improved glycemic variability.
Related JoVE Video
Cardiac transplantation followed by dose-intensive melphalan and autologous stem-cell transplantation for light chain amyloidosis and heart failure.
Transplantation
PUBLISHED: 08-25-2010
Show Abstract
Hide Abstract
Patients with light chain (AL) amyloidosis who present with severe heart failure due to cardiac involvement rarely survive more than 6 months. Survival after cardiac transplantation is markedly reduced due to the progression of amyloidosis. Autologous stem-cell transplantation (ASCT) has become a common therapy for AL amyloidosis, but there is an exceedingly high treatment-related mortality in patients with heart failure.
Related JoVE Video
Genome-wide association analysis identifies multiple loci related to resting heart rate.
Hum. Mol. Genet.
PUBLISHED: 07-16-2010
Show Abstract
Hide Abstract
Higher resting heart rate is associated with increased cardiovascular disease and mortality risk. Though heritable factors play a substantial role in population variation, little is known about specific genetic determinants. This knowledge can impact clinical care by identifying novel factors that influence pathologic heart rate states, modulate heart rate through cardiac structure and function or by improving our understanding of the physiology of heart rate regulation. To identify common genetic variants associated with heart rate, we performed a meta-analysis of 15 genome-wide association studies (GWAS), including 38,991 subjects of European ancestry, estimating the association between age-, sex- and body mass-adjusted RR interval (inverse heart rate) and approximately 2.5 million markers. Results with P < 5 × 10(-8) were considered genome-wide significant. We constructed regression models with multiple markers to assess whether results at less stringent thresholds were likely to be truly associated with RR interval. We identified six novel associations with resting heart rate at six loci: 6q22 near GJA1; 14q12 near MYH7; 12p12 near SOX5, c12orf67, BCAT1, LRMP and CASC1; 6q22 near SLC35F1, PLN and c6orf204; 7q22 near SLC12A9 and UfSp1; and 11q12 near FADS1. Associations at 6q22 400 kb away from GJA1, at 14q12 MYH6 and at 1q32 near CD34 identified in previously published GWAS were confirmed. In aggregate, these variants explain approximately 0.7% of RR interval variance. A multivariant regression model including 20 variants with P < 10(-5) increased the explained variance to 1.6%, suggesting that some loci falling short of genome-wide significance are likely truly associated. Future research is warranted to elucidate underlying mechanisms that may impact clinical care.
Related JoVE Video
Dual X-ray absorptiometry in todays clinical practice.
Radiol. Clin. North Am.
PUBLISHED: 07-09-2010
Show Abstract
Hide Abstract
Central DXA is rapid, reliable, and the most commonly used method of measuring bone mineral density in clinical practice. Although interpretation of clinical DXA scans is generally straightforward, it is important for the interpreting physician to be aware of common pitfalls and to maintain rigorous quality assurance. A firm understanding of the clinical utility of DXA allows the interpreting physician to provide valuable recommendations to treating clinicians, thereby improving the care of patients with osteoporosis. This article describes the current approach to and recent advances in the clinical use of central DXA.
Related JoVE Video
Electrocardiographic assessment for therapeutic proteins--scientific discussion.
Am. Heart J.
PUBLISHED: 07-02-2010
Show Abstract
Hide Abstract
Electrocardiographic monitoring is an integral component of the clinical assessment of cardiac safety of all compounds in development. The International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use E14 guideline recommends a dedicated study to evaluate drug-induced effects on cardiac repolarization ("thorough QT/QTc study"). There has been limited published information on QT interval changes secondary to therapeutic proteins; however, in theory, biologic therapies may affect cardiac electrical activity either directly or indirectly. This article summarizes scientific discussions of members of the Cardiac Safety Research Consortium and includes possible approaches to consider for the clinical evaluation of drug-induced QT prolongation in development programs of therapeutic proteins.
Related JoVE Video
Genome-wide association study of blood pressure extremes identifies variant near UMOD associated with hypertension.
PLoS Genet.
PUBLISHED: 05-25-2010
Show Abstract
Hide Abstract
Hypertension is a heritable and major contributor to the global burden of disease. The sum of rare and common genetic variants robustly identified so far explain only 1%-2% of the population variation in BP and hypertension. This suggests the existence of more undiscovered common variants. We conducted a genome-wide association study in 1,621 hypertensive cases and 1,699 controls and follow-up validation analyses in 19,845 cases and 16,541 controls using an extreme case-control design. We identified a locus on chromosome 16 in the 5 region of Uromodulin (UMOD; rs13333226, combined P value of 3.6 × 10?¹¹). The minor G allele is associated with a lower risk of hypertension (OR [95%CI]: 0.87 [0.84-0.91]), reduced urinary uromodulin excretion, better renal function; and each copy of the G allele is associated with a 7.7% reduction in risk of CVD events after adjusting for age, sex, BMI, and smoking status (H.R.?=?0.923, 95% CI 0.860-0.991; p?=?0.027). In a subset of 13,446 individuals with estimated glomerular filtration rate (eGFR) measurements, we show that rs13333226 is independently associated with hypertension (unadjusted for eGFR: 0.89 [0.83-0.96], p?=?0.004; after eGFR adjustment: 0.89 [0.83-0.96], p?=?0.003). In clinical functional studies, we also consistently show the minor G allele is associated with lower urinary uromodulin excretion. The exclusive expression of uromodulin in the thick portion of the ascending limb of Henle suggests a putative role of this variant in hypertension through an effect on sodium homeostasis. The newly discovered UMOD locus for hypertension has the potential to give new insights into the role of uromodulin in BP regulation and to identify novel drugable targets for reducing cardiovascular risk.
Related JoVE Video
Common variants in 22 loci are associated with QRS duration and cardiac ventricular conduction.
Nona Sotoodehnia, Aaron Isaacs, Paul I W de Bakker, Marcus Dörr, Christopher Newton-Cheh, Ilja M Nolte, Pim van der Harst, Martina Müller, Mark Eijgelsheim, Alvaro Alonso, Andrew A Hicks, Sandosh Padmanabhan, Caroline Hayward, Albert Vernon Smith, Ozren Polašek, Steven Giovannone, Jingyuan Fu, Jared W Magnani, Kristin D Marciante, Arne Pfeufer, Sina A Gharib, Alexander Teumer, Man Li, Joshua C Bis, Fernando Rivadeneira, Thor Aspelund, Anna Köttgen, Toby Johnson, Kenneth Rice, Mark P S Sie, Ying A Wang, Norman Klopp, Christian Fuchsberger, Sarah H Wild, Irene Mateo Leach, Karol Estrada, Uwe Völker, Alan F Wright, Folkert W Asselbergs, Jiaxiang Qu, Aravinda Chakravarti, Moritz F Sinner, Jan A Kors, Astrid Petersmann, Tamara B Harris, Elsayed Z Soliman, Patricia B Munroe, Bruce M Psaty, Ben A Oostra, L Adrienne Cupples, Siegfried Perz, Rudolf A de Boer, André G Uitterlinden, Henry Völzke, Timothy D Spector, Fang-Yu Liu, Eric Boerwinkle, Anna F Dominiczak, Jerome I Rotter, Gé van Herpen, Daniel Levy, H-Erich Wichmann, Wiek H van Gilst, Jacqueline C M Witteman, Heyo K Kroemer, W H Linda Kao, Susan R Heckbert, Thomas Meitinger, Albert Hofman, Harry Campbell, Aaron R Folsom, Dirk J van Veldhuisen, Christine Schwienbacher, Christopher J O'Donnell, Claudia Beu Volpato, Mark J Caulfield, John M Connell, Lenore Launer, Xiaowen Lu, Lude Franke, Rudolf S N Fehrmann, Gerard te Meerman, Harry J M Groen, Rinse K Weersma, Leonard H van den Berg, Cisca Wijmenga, Roel A Ophoff, Gerjan Navis, Igor Rudan, Harold Snieder, James F Wilson, Peter P Pramstaller, David S Siscovick, Thomas J Wang, Vilmundur Gudnason, Cornelia M van Duijn, Stephan B Felix, Glenn I Fishman, Yalda Jamshidi, Bruno H Ch Stricker, Nilesh J Samani, Stefan Kääb, Dan E Arking.
Nat. Genet.
PUBLISHED: 05-03-2010
Show Abstract
Hide Abstract
The QRS interval, from the beginning of the Q wave to the end of the S wave on an electrocardiogram, reflects ventricular depolarization and conduction time and is a risk factor for mortality, sudden death and heart failure. We performed a genome-wide association meta-analysis in 40,407 individuals of European descent from 14 studies, with further genotyping in 7,170 additional Europeans, and we identified 22 loci associated with QRS duration (P < 5 × 10(-8)). These loci map in or near genes in pathways with established roles in ventricular conduction such as sodium channels, transcription factors and calcium-handling proteins, but also point to previously unidentified biologic processes, such as kinase inhibitors and genes related to tumorigenesis. We demonstrate that SCN10A, a candidate gene at the most significantly associated locus in this study, is expressed in the mouse ventricular conduction system, and treatment with a selective SCN10A blocker prolongs QRS duration. These findings extend our current knowledge of ventricular depolarization and conduction.
Related JoVE Video

What is Visualize?

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

How does it work?

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

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

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