Feeds:
Posts
Comments

Posts Tagged ‘Atrial Fibrillation: IL6R Polymorphism in Whites and African Americans’

Curation, HealthCare System in the US, and Calcium Signaling Effects on Cardiac Contraction, Heart Failure, and Atrial Fibrillation, and the Relationship of Calcium Release at the Myoneural Junction to Beta Adrenergic Release

Curation, HealthCare System in the US, and Calcium Signaling Effects on Cardiac Contraction, Heart Failure, and Atrial Fibrillation, and the Relationship of Calcium Release at the Myoneural Junction to Beta Adrenergic Release

Curator and e-book Contributor: Larry H. Bernstein, MD, FCAP
Curator and BioMedicine e-Series Editor-in-Chief: Aviva Lev Ari, PhD, RN

and 

Content Consultant to Six-Volume e-SERIES A: Cardiovascular Diseases: Justin Pearlman, MD, PhD, FACC

This portion summarises what we have covered and is now familiar to the reader.  There are three related topics, and an extension of this embraces other volumes and chapters before and after this reading.  This approach to the document has advantages over the multiple authored textbooks that are and have been pervasive as a result of the traditional publication technology.  It has been stated by the founder of ScoopIt, that amount of time involved is considerably less than required for the original publications used, but the organization and construction is a separate creative process.  In these curations we amassed on average five articles in one curation, to which, two or three curators contributed their views.  There were surprises, and there were unfulfilled answers along the way.  The greatest problem that is being envisioned is the building a vision that bridges and unmasks the hidden “dark matter” between the now declared “OMICS”, to get a more real perspective on what is conjecture and what is actionable.  This is in some respects unavoidable because the genome is an alphabet that is matched to the mino acid sequences of proteins, which themselves are three dimensional drivers of sequences of metabolic reactions that can be altered by the accumulation of substrates in critical placements, and in addition, the proteome has functional proteins whose activity is a regulatory function and not easily identified.  In the end, we have to have a practical conception, recognizing the breadth of evolutionary change, and make sense of what we have, while searching for more.

We introduced the content as follows:

1. We introduce the concept of curation in the digital context, and it’s application to medicine and related scientific discovery.

Topics were chosen were used to illustrate this process in the form of a pattern, which is mostly curation, but is significantly creative, as it emerges in the context of this e-book.

  • Alternative solutions in Treatment of Heart Failure (HF), medical devices, biomarkers and agent efficacy is handled all in one chapter.
  • PCI for valves vs Open heart Valve replacement
  • PDA and Complications of Surgery — only curation could create the picture of this unique combination of debate, as exemplified of Endarterectomy (CEA) vs Stenting the Carotid Artery (CAS), ischemic leg, renal artery stenosis.

2. The etiology, or causes, of cardiovascular diseases consist of mechanistic explanations for dysfunction relating to the heart or vascular system. Every one of a long list of abnormalities has a path that explains the deviation from normal. With the completion of the analysis of the human genome, in principle all of the genetic basis for function and dysfunction are delineated. While all genes are identified, and the genes code for all the gene products that constitute body functions, there remains more unknown than known.

3. Human genome, and in combination with improved imaging methods, genomics offers great promise in changing the course of disease and aging.

4. If we tie together Part 1 and Part 2, there is ample room for considering clinical outcomes based on individual and organizational factors for best performance. This can really only be realized with considerable improvement in information infrastructure, which has miles to go.

Curation

Curation is an active filtering of the web’s  and peer reviewed literature found by such means – immense amount of relevant and irrelevant content. As a result content may be disruptive. However, in doing good curation, one does more than simply assign value by presentation of creative work in any category. Great curators comment and share experience across content, authors and themes.
Great curators may see patterns others don’t, or may challenge or debate complex and apparently conflicting points of view.  Answers to specifically focused questions comes from the hard work of many in laboratory settings creatively establishing answers to definitive questions, each a part of the larger knowledge-base of reference. There are those rare “Einstein’s” who imagine a whole universe, unlike the three blindmen of the Sufi tale.  One held the tail, the other the trunk, the other the ear, and they all said this is an elephant!
In my reading, I learn that the optimal ratio of curation to creation may be as high as 90% curation to 10% creation. Creating content is expensive. Curation, by comparison, is much less expensive.  The same source says “Scoop.it is my content marketing testing “sandbox”. In sharing, he says that comments provide the framework for what and how content is shared.

Healthcare and Affordable Care Act

We enter year 2014 with the Affordable Care Act off to a slow start because of the implementation of the internet signup requiring a major repair, which is, unfortunately, as expected for such as complex job across the US, and with many states unwilling to participate.  But several states – California, Connecticut, and Kentucky – had very effective state designed signups, separate from the federal system.  There has been a very large rush and an extension to sign up. There are many features that we can take note of:

1. The healthcare system needed changes because we have the most costly system, are endowed with advanced technology, and we have inexcusable outcomes in several domains of care, including, infant mortality, and prenatal care – but not in cardiology.

2. These changes that are notable are:

  • The disparities in outcome are magnified by a large disparity in highest to lowest income bracket.
  • This is also reflected in educational status, and which plays out in childhood school lunches, and is also affected by larger class size and cutbacks in school programs.
  • This is not  helped by a large paralysis in the two party political system and the three legs of government unable to deal with work and distraction.
  • Unemployment is high, and the banking and home construction, home buying, and rental are in realignment, but interest rates are problematic.

3.  The  medical care system is affected by the issues above, but the complexity is not to be discounted.

  •  The medical schools are unable at this time to provide the influx of new physicians needed, so we depend on a major influx of physicians from other countries
  • The technology for laboratories, proteomic and genomic as well as applied medical research is rejuvenating the practice in cardiology more rapidly than any other field.
  • In fields that are imaging related the life cycle of instruments is shorter than the actual lifetime use of the instruments, which introduces a shortening of ROI.
  • Hospitals are consolidating into large consortia in order to maintain a more viable system for referral of specialty cases, and also is centralizing all terms of business related to billing.
  • There is reduction in independent physician practices that are being incorporated into the hospital enterprise with Part B billing under the Physician Organization – as in Partners in Greater Boston, with the exception of “concierge” medical practices.
  • There is consolidation of specialty laboratory services within state, with only the most specialized testing going out of state (Quest, LabCorp, etc.)
  • Medicaid is expanded substantially under the new ACA.
  • The federal government as provider of services is reducing the number of contractors for – medical devices, diabetes self-testing, etc.
  • The current rearrangements seeks to provide a balance between capital expenses and fixed labor costs that it can control, reduce variable costs (reagents, pharmaceutical), and to take in more patients with less delay and better performance – defined by outside agencies.

Cardiology, Genomics, and calcium ion signaling and ion-channels in cardiomyocyte function in health and disease – including heart failure, rhythm abnormalities, and the myoneural release of neurotransmitter at the vesicle junction.

This portion is outlined as follows:

2.1 Human Genome: Congenital Etiological Sources of Cardiovascular Disease

2.2 The Role of Calcium in Health and Disease

2.3 Vasculature and Myocardium: Diagnosing the Conditions of Disease

Genomics & Genetics of Cardiovascular Disease Diagnoses

actin cytoskeleton

wall stress, ventricular workload, contractile reserve

Genetic Base of Atherosclerosis and Loss of Arterial Elasticity with Aging

calcium and actin skeleton, signaling, cell motility

hypertension & vascular compliance

Genetics of Conduction Disease

Ca+ stimulated exostosis: calmodulin & PKC (neurotransmitter)

complications & MVR

disruption of Ca2+ homeostasis cardiac & vascular smooth muscle

synaptotagmin as Ca2+ sensor & vesicles

atherosclerosis & ion channels


It is increasingly clear that there are mutations that underlie many human diseases, and this is true of the cardiovascular system.  The mutations are mistakes in the insertion of a purine nucleotide, which may or may not have any consequence.  This is why the associations that are being discovered in research require careful validation, and even require demonstration in “models” before pursuing the design of pharmacological “target therapy”.  The genomics in cardiovascular disease involves very serious congenital disorders that are asserted early in life, but the effects of and development of atherosclerosis involving large and medium size arteries has a slow progression and is not dominated by genomic expression.  This is characterized by loss of arterial elasticity. In addition there is the development of heart failure, which involves the cardiomyocyte specifically.  The emergence of regenerative medical interventions, based on pleuripotent inducible stem cell therapy is developing rapidly as an intervention in this sector.

Finally, it is incumbent on me to call attention to the huge contribution that research on calcium (Ca2+) signaling has made toward the understanding of cardiac contraction and to the maintenance of the heart rhythm.  The heart is a syncytium, different than skeletal and smooth muscle, and the innervation is by the vagus nerve, which has terminal endings at vesicles which discharge at the myocyte junction.  The heart specifically has calmodulin kinase CaMK II, and it has been established that calmodulin is involved in the calcium spark that triggers contraction.  That is only part of the story.  Ion transport occurs into or out of the cell, the latter termed exostosis.  Exostosis involves CaMK II and pyruvate kinase (PKC), and they have independent roles.  This also involves K+-Na+-ATPase.  The cytoskeleton is also discussed, but the role of aquaporin in water transport appears elsewhere, as the transport of water between cells.  When we consider the Gibbs-Donnan equilibrium, which precedes the current work by a century, we recall that there is an essential balance between extracellular Na+ + Ca2+ and the intracellular K+ + Mg2+, and this has been superceded by an incompletely defined relationship between ions that are cytoplasmic and those that are mitochondrial.  The glass is half full!

 

Read Full Post »

Atrial Fibrillation: IL6R Polymorphism in Whites and African Americans

Reporter: Aviva Lev-Ari, PhD, RN

Large-Scale Candidate Gene Analysis in Whites and African Americans Identifies IL6R Polymorphism in Relation to Atrial Fibrillation

The National Heart, Lung, and Blood Institute’s Candidate Gene Association Resource (CARe) Project

Renate B. Schnabel, MD, MSc*Kathleen F. Kerr, PhD*Steven A. Lubitz, MD*,Ermeg L. Alkylbekova, MD*Gregory M. Marcus, MD, MAS, Moritz F. Sinner, MD,Jared W. Magnani, MD, Philip A. Wolf, MD, Rajat Deo, MD, Donald M. Lloyd-Jones, MD, ScM, Kathryn L. Lunetta, PhD, Reena Mehra, MD, MS, Daniel Levy, MD, Ervin R. Fox, MD, MPH, Dan E. Arking, PhD, Thomas H. Mosley, PhD, Martina Müller-Nurasyid, MSc, PhD, Taylor R. Young, MA, H.-Erich Wichmann, MD, PhD, Sudha Seshadri, MD,Deborah N. Farlow, PhD, Jerome I. Rotter, MD, Elsayed Z. Soliman, MD, MSc, MS,Nicole L. Glazer, PhD, James G. Wilson, MD, Monique M.B. Breteler, MD, Nona Sotoodehnia, MD, MPH, Christopher Newton-Cheh, MD, MPH, Stefan Kääb, MD, PhD,Patrick T. Ellinor, MD, PhD*Alvaro Alonso, MD*Emelia J. Benjamin, MD, ScM*,Susan R. Heckbert, MD, PhD* and for the Candidate Gene Association Resource (CARe) Atrial Fibrillation/Electrocardiography Working Group

Correspondence to Susan R. Heckbert, MD, PhD, Cardiovascular Health Research Unit, University of Washington, 1730 Minor Ave, Suite 1360, Seattle, WA 98101. E-mail heckbert@u.washington.edu; Emelia J. Benjamin, MD, ScM, Medicine andEpidemiology, Boston University Schools of Medicine and Public Health, The Framingham Heart Study, 73 Mount Wayte Ave, Framingham, MA 01702–5827. E-mail emelia@bu.edu; Renate B. Schnabel, MD, MSc, Department of Medicine 2, Cardiology, Johannes Gutenberg University, Langenbeckstr 1, 55131 Mainz, Germany. E-mail schnabelr@gmx.de

* These authors contributed equally to the manuscript.

Abstract

Background—The genetic background of atrial fibrillation (AF) in whites andAfrican Americans is largely unknown. Genes in cardiovascular pathways have not been systematically investigated.

Methods and Results—We examined a panel of approximately 50 000 common single-nucleotide polymorphisms (SNPs) in 2095 cardiovascular candidate genesand AF in 3 cohorts with participants of European (n=18 524; 2260 cases) or African American descent (n=3662; 263 cases) in the National Heart, Lung, andBlood Institute’s Candidate Gene Association Resource. Results in whites were followed up in the German Competence Network for AF (n=906, 468 cases). The top result was assessed in relation to incident ischemic stroke in the Cohorts for Heartand Aging Research in Genomic Epidemiology Stroke Consortium (n=19 602 whites, 1544 incident strokes). SNP rs4845625 in the IL6R gene was associated with AF (relative risk [RR] C allele, 0.90; 95% confidence interval [CI], 0.85–0.95;P=0.0005) in whites but did not reach statistical significance in African Americans (RR, 0.86; 95% CI, 0.72–1.03; P=0.09). The results were comparable in the German AF Network replication, (RR, 0.71; 95% CI, 0.57–0.89; P=0.003). No association between rs4845625 and stroke was observed in whites. The known chromosome 4 locus near PITX2 in whites also was associated with AF in African Americans (rs4611994; hazard ratio, 1.40; 95% CI, 1.16–1.69; P=0.0005).

Conclusions—In a community-based cohort meta-analysis, we identified genetic association in IL6R with AF in whites. Additionally, we demonstrated that the chromosome 4 locus known from recent genome-wide association studies in whites is associated with AF in African Americans.

 SOURCE:

Circulation: Cardiovascular Genetics.2011; 4: 557-564

Published online before print August 16, 2011,

doi: 10.1161/ CIRCGENETICS.110.959197

Read Full Post »