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  • Has Human Evolution Stopped?

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important impli-cations for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the hu-man gene pool, thereby enhancing the potential for human evolution. The increase in human popula-tion size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual het-erozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.
  • Intelligent Design versus Evolution

    Intelligent Design (ID) burst onto the scene in 1996, with the publication of Darwin’s Black Box by Mi-chael Behe. Since then, there has been a plethora of articles written about ID, both pro and con. How-ever, most of the articles critical of ID deal with peripheral issues, such as whether ID is just another form of creationism or whether ID qualifies as science or whether ID should be taught in public schools. It is our view that the central issue is whether the basic claim of ID is correct. Our goal is fourfold: (I) to show that most of the proposed refutations of ID are unconvincing and/or incorrect, (II) to describe the single fundamental error of ID, (III) to discuss the historic tradition surrounding the ID controversy, showing that ID is an example of a “god-of-the-gaps” argument, and (IV) to place the ID controversy in the larger context of proposed proofs for the existence of God, with the emphasis on Jewish tradition.
  • MRI-Guided Electrophysiology Intervention

    Catheter ablation is a first-line treatment for many cardiac arrhythmias and is generally performed under X-ray fluoroscopy guidance. However, current techniques for ablating complex arrhythmias such as atrial fibrillation and ventricular tachycardia are associated with sub-optimal success rates and prolonged radiation exposure. Pre-procedure 3-D magnetic resonance imaging (MRI) has improved understanding of the anatomic basis of complex arrhythmias and is being used for planning and guidance of ablation procedures. A particular strength of MRI compared to other imaging modalities is the ability to visualize ablation lesions. Post-procedure MRI is now being applied to assess ablation lesion location and permanence with the goal of identifying factors leading to procedure success and failure. In the future, intra-procedure real-time MRI, together with the ability to image complex 3-D arrhythmogenic anatomy and target additional ablation to regions of incomplete lesion formation, may allow for more successful treatment of even complex arrhythmias without exposure to ionizing radiation. Development of clinical grade MRI-compatible electrophysiology devices is required to transition intra-procedure MRI from preclinical studies to more routine use in patients.
  • The Next Revolution: Percutaneous Aortic Valve Replacement

    Aortic valve replacement (AVR) is a treatment of choice for patients with symptomatic severe aortic stenosis (AS). However, a significant proportion of these patients do not undergo surgical AVR due to high-risk features. Transcatheter aortic valve implantation (TAVI) has emerged as an alternative for patients with severe AS who are not candidates for open-heart surgery. Since the introduction of TAVI to the medical community in 2002, there has been an explosive growth in procedures. The balloon-expandable Edwards SAPIEN valve and the self-expanding CoreValve ReValvingTM system contribute the largest patient experience with more than 10,000 patients treated with TAVI to date. Clinical out-comes have stabilized in experienced hands, with 30-day mortality less than 10%. Careful patient selection, growing operator experience, and an integrated multidisciplinary team approach contribute to notable improvement in outcomes. In the first randomized pivotal PARTNER trial, in patients with severe AS not suitable candidates for surgical AVR, TAVI compared with standard therapy, significantly improved survival and cardiac symptoms, but was associated with higher incidence of major strokes and major vascular events. The results of randomized comparison of TAVI with AVR among high-risk patients with AS for whom surgery is a viable option are eagerly awaited to provide further evidence on the applicability of TAVI in these patients.
  • Maimonides' Appreciation for Medicine

    Moses Maimonides, the illustrious medieval rabbi and philosopher, dedicated the last decade of his life primarily to medicine. His strong interest in medicine was an integral component of his religious-philosophical teachings and world view. In this paper various sources from his rabbinic writings are presented that explain Maimonides’ motivation regarding and deep appreciation for medicine: (A) The physician fulfills the basic biblical obligation to return lost objects to their owner, for with his knowledge and experience the physician can restore good health to his sick fellow human being; (B) medicine provides a unique opportunity to practice imitatio dei, as it reflects the religious duty to maintain a healthy life-style; (C) as an important natural science, medicine offers tools to recognize, love and fear God. These three aspects address man’s relationship and obligation towards his fellow man, himself and God. Biographical insights supported by additional sources from Maimonides’ writings are discussed.
  • Milestones in the Evolution of Hepatic Surgery

    This paper describes the rapid evolution of modern liver surgery, starting in the middle of the twentieth century. Claude Couinaud studied and described the segmental anatomy of the liver, Thomas Starzl performed the first liver transplantations, and Henri Bismuth introduced the concept of anatomical resections. Hepatic surgery has developed significantly since those early days. To date, innovative techniques are applied, using cutting-edge technologies: Intraoperative ultrasound, techniques of vascular exclusion of the liver, new devices for performing homeostasis and dissection, laparoscopy for resections, and new drugs that allow the resection of previously unresectable tumors. The next stage in liver surgery will probably be the implementation of a multidisciplinary holistic approach to the liver-diseased patient that will ensure the best and most efficient treatments in the future.
  • Systematic Quality Improvement in Medicine: Everyone Can Do It

    In this brief review, written from the perspective of a physician-leader who has fostered the development of comprehensive quality improvement efforts at two academic medical centers, I review the need for improvement, some conceptual barriers that must be overcome, the goals of a comprehensive quality improvement (QI) effort, some of the results we have obtained, and some observations on how to develop a culture of continuous improvement in an academic medical center. The mandate for quality improvement is clear; current healthcare is wasteful and error-prone, leading to excessive morbidity and mortality and unsustainably high costs. Successful quality improvement requires the abandonment of two paradigms: the craft model of medical practice and the notion that many forms of harm to patients are not preventable. I will describe how dramatic improvement has been achieved in reducing, by up to 10-fold, rates of central line infections, ventilator-associated pneumonias, peritonitis in peritoneal dialysis patients, and mortality due to cardiac arrest in hospital. I will describe as well how these methods can improve access to out-patient clinics dramatically and enhance the reliability and safety of hand-offs between covering physicians. To develop and maintain systematic quality improvement in all phases of medical care we must articulate a culture in which: everyone working at the medical center makes improvements every day; front-line staff, who know best how the work is done, are empowered to improve the processes of care; and multidisciplinary teams create the protocols that reduce variation that is due to physician preference, leaving only the variation required by the individual needs of patients. I will review as well the crucial elements of education of trainees and faculty members needed to guide and sustain a culture of quality. Finally, I will add some observations on how oversight boards and medical center leaders can help create systematic quality improvement in their medical centers.
  • The Role for Insulin and Insulin-like Growth Factors in the Increased Risk of Cancer in Diabetes

    Patients with type 2 diabetes (T2D) are at increased risk of developing cancer. This evidence arises from numerous epidemiologic studies that relate a positive association between T2D and cancer. In-vitro and several in-vivo experiments have attempted to discern the potential mechanistic factors involved in this relationship. Candidates include hyperinsulinemia, insulin-like growth factor-1 (IGF-1), and insulin-like growth factor-2 (IGF-2) signaling. These studies demonstrated that increased insulin, IGF-1, and IGF-2 signaling through the insulin receptor and IGF-1 receptor can induce cancer development and progression.
  • At the Edge of Viability: Moral and Ethical Guideline Proposals

    The paper proposes moral and ethical guidelines for medical treatment at the edge of viability. The proposed principles are defended on the grounds of a general conceptual framework presented by elucidating the notions of viability, the edge of viability, person, sanctity of human life, dignity, and the slope of dignity protection, as well as the distinction between ethics and morality.
  • New Insights in Celiac Disease

    Celiac disease (CD) is an autoimmune disorder occurring in genetically susceptible subjects. The incidence of CD is around 1%, and it is much more common in first-degree relatives of CD patients, 10%–18%. However, the pattern of the genetic inheritance is still obscure. Environmental factors are undoubtedly affecting the disease’s clinical presentation, time at presentation, and maybe effect on the characteristics of the disease. The clinical presentation of CD has shifted during the previous decades from the classical presentation in which the toddler suffers from diarrhea, constipation, vomiting, failure to thrive, abdominal distension, etc., to the child with a monosymptomatic presentation, such as anemia, as well as an enlarged list of extra-intestinal disorders. The diagnosis of CD is being established by symptoms consistent with CD and positive serology. The ultimate diagnosis should be made upon histological evaluation of the small bowel mucosa. The treatment of CD is a lifelong, strict gluten-free diet (GFD). Compliance with a GFD is quite difficult. Therefore, new strategies for prevention and treatment modalities other than GFD are greatly needed. Recently several promising therapeutic modalities have been developed; these include resuming traditional baking techniques. Another methodology is using probiotic-driven prolylendopeptidase. Another pathway to tackle the therapeutic option in CD is by down-regulation of the activity of zonulin—the active pump enabling gluten to enter the enterocytes. We are facing an era where other modalities beyond a GFD might allow CD patients to be able to tolerate occasionally a small amount of gluten in their diet.