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  • Mitochondrial Replacement Therapy: Halachic Considerations for Enrolling in an Experimental Clinical Trial

    The transition of new biotechnologies into clinical trials is a critical step in approving a new drug or therapy in health care. Ethically recruiting appropriate volunteers for these clinical trials can be a challenging task for both the pharmaceutical companies and the US Food and Drug Administration. In this paper we analyze the Jewish halachic perspectives of volunteering for clinical trials by focusing on an innovative technology in reproductive medicine, mitochondrial replacement therapy. The halachic perspective encourages individuals to volunteer for such clinical trials under the ethical principles of beneficence and social responsibility, when animal studies have shown that health risks are minimal.
  • The Egg and the Nucleus: A Battle for Supremacy

    This brief introduction is followed by a published version of my Nobel Laureate lecture, re-published herein with the kind permission of the Nobel Foundation. Much has happened since my original research, for which that prize was awarded. Hence, I am pleased to offer a few thoughts about the future of my research and its possible impact on humankind. Although the original work on nuclear transfer and reprogramming was done over half a century ago, advances continue to be made. In particular the Takahashi and Yamanaka induced pluripotent stem cells (iPS) procedure has opened up the field of cell replacement to a great extent. Now, more recently, further advances make this whole field come closer to actual usefulness for humans. Recently, in the UK, the government approved the use of mitochondrial replacement therapy to avoid the problems associated with genetically defective mitochondria in certain women. Although the House of Commons (members of Parliament) and the House of Lords had to debate and discuss whether to allow this kind of human therapy, I was very pleased to find that both bodies approved this procedure. This means that a patient can choose to make use of the procedure; it does not in any way force an individual to have a procedure that they are not comfortable with. In my view, this is a great advance in respect to giving patients a choice about the treatment they receive. I am told that the UK is the first country in the world to approve mitochondrial replacement therapy. Now that the Clustered Regularly Interspaced Short Palindromic Repeat (CRISPr) technology is being widely used and works well, one can foresee that there will be those who wish to use this technology to make genetic changes to humans. For example, if a human has a gene that makes it susceptible to infection or any other disorder, the removal of that gene might give such a person immunity from that disease. If this gene deletion is done within the germ line, the genetic change will be inherited. However, one can imagine that various people will strongly object and say that this technology should not be allowed. I would very much hope that various regulatory bodies, governments, etc. will allow the choice to remain with the individual. I can see no argument for such bodies to make a law that removes any choice whatsoever by an individual.
  • Role of Regulatory T Cells (Treg) and the Treg Effector Molecule Fibrinogen-like Protein 2 in Alloimmunity and Autoimmunity

    CD4+CD25+Foxp3+ regulatory T cells (Treg) are critical to the maintenance of immune tolerance. Treg are known to utilize a number of molecular pathways to control immune responses and maintain immune homeostasis. Fibrinogen-like protein 2 (FGL2) has been identified by a number of investigators as an important immunosuppressive effector of Treg, which exerts its immunoregulatory activity by binding to inhibitory FcγRIIB receptors expressed on antigen-presenting cells including dendritic cells, endothelial cells, and B cells. More recently, it has been suggested that FGL2 accounts for the immunosuppressive activity of a highly suppressive subset of Treg that express T cell immunoreceptor with Ig and ITIM domains (TIGIT). Here we discuss the important role of Treg and FGL2 in preventing alloimmune and autoimmune disease. The FGL2–FcγRIIB pathway is also known to be utilized by viruses and tumor cells to evade immune surveillance. Moving forward, therapies based on modulation of the FGL2–FcγRIIB pathway hold promise for the treatment of a wide variety of conditions ranging from autoimmunity to cancer.
  • The Number Needed to Treat: 25 Years of Trials and Tribulations in Clinical Research

    The number needed to treat (NNT) is a simple measure of a treatment’s impact, increasingly reported in randomized trials and observational studies. It has been found to be incorrectly calculated in several studies involving varying follow-up times. We discuss the NNT in these contexts and illustrate the concept using several published studies. The computation of the NNT is founded on the cumulative incidence of the outcome. Instead, several published studies use simple proportions that do not account for varying follow-up times, or use incidence rates per person-time. We show how these approaches can lead to erroneous values of the NNT and misleading interpretations. For example, a trial of 3,845 very elderly hypertensives randomized to a diuretic or placebo reported a NNT of 94 treated for 2 years to prevent one stroke, though the correct approach results in a NNT of 63. We also note that meta-analyses involve trials of differing lengths, but often report a single NNT. For example a meta-analysis of 22 trials of the anticholinergic tiotropium in chronic obstructive pulmonary disease reported a NNT of 16 patients “over one year,” even if the trials varied in duration from 3 to 48 months, with the more specifically computed NNTs varying widely from 72, 15, and 250 for the 3-month, 12-month, and 48-month trials, respectively. Finally, we describe the value of the NNT in assessing benefit–risk, such as low-dose aspirin use in secondary prevention, where prevention of mortality was assessed against the risk of gastrointestinal bleeding. As the “number needed to treat” becomes increasingly used in the comparative effectiveness and safety of therapies, its accurate estimation and interpretation become crucial to avoid distorting clinical, economic, and public health decisions.
  • Lung Edema Clearance: Relevance to Patients with Lung Injury

    Pulmonary edema clearance is necessary for patients with lung injury to recover and survive. The mechanisms regulating edema clearance from the lungs are distinct from the factors contributing edema formation during injury. Edema clearance is effected via vectorial transport of Na+ out of the airspaces which generates an osmotic gradient causing water to follow the gradient out of the cells. This Na+ transport across the alveolar epithelium is mostly effected via apical Na+ and chloride channels and basolateral Na,K-ATPase. The Na,K-ATPase pumps Na+ out of the cell and K+ into the cell against their respective gradients in an ATP-consuming reaction. Two mechanisms contribute to the regulation of the Na,K-ATPase activity:recruitment of its subunits from intracellular compartments into the basolateral membrane, and transcriptional/translational regulation. Na,K-ATPase activity and edema clearance are increased by catecholamines, aldosterone, vasopressin, overexpression of the pump genes, and others. During lung injury, mechanisms regulating edema clearance are inhibited by yet unclear pathways. Better understanding of the mechanisms that regulate pulmonary edema clearance may lead to therapeutic interventions that counterbalance the inhibition of edema clearance during lung injury and improve the lungs’ ability to clear fluid, which is crucial for patient survival.
  • Secondary Guilt Syndrome May Have Led Nazi-persecuted Jewish Writers to Suicide

    Feelings of guilt have tormented Holocaust survivors, ranging from immediately after the liberation to later in life, for shorter or longer periods, and persisting for some throughout their entire post-war lives. Descriptions of the guilt experienced by survivors of the Nazi camps occupy an impressive amount of literature: “Why me?” was the question, when a younger and more able family member perished; “Why me?” when more productive members of the community perished; “Why me?” when a million and a half children were deprived of their lives. Many found the answer by retelling their stories, witnesses of what happened. This type of guilt is much different from the recently described phenomenon of survivor syndrome, namely the secondary guilt felt by Nazi-persecuted Jewish writers. Despite successes in all aspects of their life, these writers developed a self-incriminating guilt due to their perceived inadequacy of communicating, particularly in light of the resurging anti-Semitism worldwide. This paper deals with the survival and suicides of Nazi-persecuted Jewish writers and offers a possible explanation for their late self-destructive acts.
  • The Envy of Scholars: Applying the Lessons of the Framingham Heart Study to the Prevention of Chronic Kidney Disease

    During the past 50 years, a dramatic reduction in the mortality rate associated with cardiovascular disease has occurred in the US and other countries. Statistical modeling has revealed that approximately half of this reduction is the result of risk factor mitigation. The successful identification of such risk factors was pioneered and has continued with the Framingham Heart Study, which began in 1949 as a project of the US National Heart Institute (now part of the National Heart, Lung, and Blood Institute). Decreases in total cholesterol, blood pressure, smoking, and physical inactivity account for 24%, 20%, 12%, and 5% reductions in the mortality rate, respectively. Nephrology was designated as a recognized medical professional specialty a few years later. Hemodialysis was first performed in 1943. The US Medicare End-Stage Renal Disease (ESRD) Program was established in 1972. The number of patients in the program increased from 5,000 in the first year to more than 500,000 in recent years. Only recently have efforts for risk factor identification, early diagnosis, and prevention of chronic kidney disease (CKD) been undertaken. By applying the approach of the Framingham Heart Study to address CKD risk factors, we hope to mirror the success of cardiology; we aim to prevent progression to ESRD and to avoid the cardiovascular complications associated with CKD. In this paper, we present conceptual examples of risk factor modification for CKD, in the setting of this historical framework.
  • The Clinical Significance of Ependymal Enhancement at Presentation in Patients with Malignant Glioma

    Introduction. The current study evaluated the rate of ependymal enhancement and whether its presence influences survival of patients with malignant glioma (GBM). Methods. A retrospective review of all patients who were treated in our institution from 2005 to 2011 was conducted. Data extracted from the medical records included age, date of diagnosis, co-morbidities, treatment regimen, and time of death. Magnetic resonance images (MRI) were evaluated for the presence of ependymal enhancement and its extent, and the correlation to survival was investigated. Results. Between 2005 and 2011, 230 patients were treated for GBM. Eighty-nine patients were excluded from the study due to insufficient data, leaving 141 patients for analysis. Median age at diagnosis was 60 years. Sixty-seven (40.6%) patients had evidence of ependymal enhancement on MRI (group A), and 70 (42.4%) patients did not have evidence of enhancement. The assessment of ependymal enhancement was inconclusive due to mass effect and ventricular compression that precluded accurate assessment for 28 (17%) patients (group C). Median survival was 14 months for group A (range, 12–16 months), 15.9 months for group B (range, 14.28–17.65 months), and 11.7 months for group C (range, 6.47–16.92 months) (P>0.05). A multivariate analysis to predict survival indicated that male gender (P=0.039), hypertension (P=0.012), and biopsy only compared to complete gross tumor resection (P=0.001) were significant for poor survival. Conclusions. Pretreatment ependymal enhancement on MRI was not found to be associated with poorer survival. These results might be due to better treatments options compared to prior reports.
  • The Long and Winding Road to Innovation

    Medicine is developing through biomedical technology and innovations. The goal of any innovation in medicine is to improve patient care. Exponential growth in technology has led to the unprecedented growth of medical technology over the last 50 years. Clinician-scientists need to understand the complexity of the innovation process, from concept to product release, when working to bring new clinical solutions to the bedside. Hence, an overview of the innovation process is provided herein. The process involves an invention designed to solve an unmet need, followed by prototype design and optimization, animal studies, pilot and pivotal studies, and regulatory approval. The post-marketing strategy relative to funding, along with analysis of cost benefit, is a critical component for the adoption of new technologies. Examples of the road to innovation are provided, based on the experience with development of the transcatheter aortic valve. Finally, ideas are presented to contribute to the further development of this worldwide trend in innovation.
  • Reply to Professionalism—The Role of Quality Improvement

    I appreciate Dr Walsh’s feedback regarding my recent article, “Teaching and Assessing Profession-alism in Medical Learners and Practicing Physicians.” I agree with Dr Walsh that quality improvement is a topic of importance within the professionalism domain. ...