19 results on '"Poyan-Mehr A"'
Search Results
2. The Implementation of a Virtual Home Dialysis Mentoring Program for Nephrologists
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Ali Poyan Mehr, Christopher Chan, Brigitte Schiller, and Graham Abra
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Nephrologists ,education ,Mentors ,Hemodialysis, Home ,Humans ,Kidney Failure, Chronic ,Mentoring ,General Medicine ,Brief Communication ,Peritoneal Dialysis ,GeneralLiterature_MISCELLANEOUS - Abstract
Virtual home dialysis physician mentorship is feasible. In total, 53% of participants perceived the program would change the perspective of participants on prescribing home dialysis. More research is needed to ascertain the effect of virtual mentorship on home dialysis incidence and attrition rates in a wider audience.
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- 2022
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3. Innovating and invigorating the clinical trial infrastructure for glomerular diseases
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Meg Jardine, Moin A. Saleem, Kimberly Smith, Irv Smokler, Matthias Kretzler, Debbie S. Gipson, Lauren Eva, Jun Oh, Elaine S. Kamil, Aliza Thompson, Josh Tarnoff, Barbara S. Gillespie, Patrick D. Walker, Lauren Lee, Elena Levtchenk, Patrick H. Nachman, Melissa West, Marina Vivarelli, Tobias B. Huber, Jonathan Barratt, Stuart J. Shankland, Brad H. Rovin, Howard Trachtman, Ali Poyan Mehr, Suneel Udani, Kirk N. Campbell, Laura Barisoni, and William E. Smoyer
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medicine.medical_specialty ,business.industry ,Glomerulonephritis ,Patient engagement ,medicine.disease ,law.invention ,Clinical trial ,Randomized controlled trial ,Nephrology ,law ,Internal medicine ,medicine ,Humans ,Kidney Diseases ,business ,Glomerular diseases - Published
- 2021
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4. Glomerular Disease Education Experience across Nephrology Fellowship Programs: An International Survey
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Harish Seethapathy, Sayna Norouzi, Kate J. Robson, Lida Gharibvand, and Ali Poyan Mehr
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education ,RC648-665 ,Diseases of the endocrine glands. Clinical endocrinology - Abstract
Introduction: Glomerulonephritis (GN) education is an important, albeit a challenging, component of nephrology fellowship training. We hypothesized that trainee experience varies widely across programs, leading to differences in self-reported competency levels in the diagnosis and management of glomerular diseases. Methods: The Glomerular Disease Study & Trial Consortium (GlomCon) conducted an anonymous online survey to determine the educational experience of nephrology trainees. We used multiple-choice questions to obtain data about (a) curriculum-based education, (b) dedicated specialty clinic, and (c) exposure to pathology. We leveraged a visual analog scale of 1–100 (with a higher number indicating a higher comfort level) to assess self-reported levels of clinical competency. The survey was disseminated via email to the subscribing members of GlomCon and through Twitter. Results: In total, there were 109 respondents to our survey, and 56% were from training programs in the USA. Exposure to a specialized GN clinic was reported by 45%, while 77% reported the presence of an onsite nephropathologist at their training program. Self-reported competency scores were 59 ± 25 and 52 ± 25 for diagnosis and treatment of glomerular diseases, respectively. Days spent in a GN clinic per year, years of fellowship, and dedicated nephropathology didactics were associated with higher diagnosis and treatment competency scores. Conclusion: Trainees report a wide variation in glomerular disease education across fellowship programs. A lack of nephropathology exposure and a dedicated GN curriculum was associated with lower scores in self-reported clinical competency in caring for patients with glomerular disease.
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- 2021
5. The use of virtual physician mentoring to enhance home dialysis knowledge and uptake
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Ali Poyan Mehr, Brigitte Schiller, Paul Bennett, Justin Ashley, Christopher T. Chan, Joanne M. Bargman, Graham Abra, Ashley, Justin, Abra, Graham, Schiller, Brigitte, Bennett, Paul N, Mehr, Ali Poyan, Bargman, Joanne M, and Chan, Christopher T
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medicine.medical_treatment ,030232 urology & nephrology ,Hemodialysis, Home ,030204 cardiovascular system & hematology ,Peritoneal dialysis ,home dialysis ,project ECHO ,Nephrologists ,03 medical and health sciences ,User-Computer Interface ,0302 clinical medicine ,Mentorship ,Nursing ,Pandemic ,medicine ,Home dialysis ,Humans ,business.industry ,SARS-CoV-2 ,Home hemodialysis ,Teaching ,COVID-19 ,General Medicine ,virtual mentorship ,medicine.disease ,peritoneal dialysis ,Nephrology ,Scale (social sciences) ,Kidney Failure, Chronic ,Education, Medical, Continuing ,home haemodialysis ,business ,Developed country ,Kidney disease - Abstract
Home dialysis therapies are flexible kidney replacement strategies with documented clinical benefits. While the incidence of end-stage kidney disease continues to increase globally, the use of home dialysis remains low in most developed countries. Multiple barriers to providing home dialysis have been noted in the published literature. Among known challenges, gaps in clinician knowledge are potentially addressable with a focused education strategy. Recent national surveys in the United States and Australia have highlighted the need for enhanced home dialysis knowledge especially among nephrologists who have recently completed training. Traditional in-person continuing professional educational programmes have had modest success in promoting home dialysis and are limited by scale and the present global COVID-19 pandemic. We hypothesize that the use of a ‘Hub and Spoke’ model of virtual home dialysis mentorship for nephrologists based on project ECHO would support home dialysis growth. We review the home dialysis literature, known educational gaps and plausible educational interventions to address current limitations in physician education Refereed/Peer-reviewed
- Published
- 2021
6. Niacinamide May Be Associated with Improved Outcomes in COVID-19-Related Acute Kidney Injury: An Observational Study
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Kenneth J. Mukamal, Samir M. Parikh, Ali Poyan Mehr, Nathan Raines, Pitchaphon Nissaisorakarn, Theodore I. Steinman, Alexander Morales, Rahul Maheshwari, Vigyan Bang, Sourbha S. Dani, Mehrnaz Sadrolashrafi, Aarti Asnani, Amitoj Singh, Katherine Shreyder, Robert S. Brown, Johannes Schlondorff, Sarju Ganatra, Amar Pandit, Mark L. Zeidel, Rushin Patel, Sarah Knapp, Simarjeet Brar, and Rhea Bhargava
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Adult ,Niacinamide ,Vitamin ,medicine.medical_specialty ,Original Investigations ,Lower risk ,urologic and male genital diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Renal Dialysis ,Risk Factors ,Internal medicine ,medicine ,Humans ,Prospective Studies ,030212 general & internal medicine ,Stage (cooking) ,Retrospective Studies ,030304 developmental biology ,0303 health sciences ,Creatinine ,business.industry ,Acute kidney injury ,COVID-19 ,General Medicine ,Acute Kidney Injury ,medicine.disease ,female genital diseases and pregnancy complications ,chemistry ,Observational study ,Complication ,business - Abstract
BACKGROUND: AKI is a significant complication of coronavirus disease 2019 (COVID-19), with no effective therapy. Niacinamide, a vitamin B3 analogue, has some evidence of efficacy in non-COVID-19-related AKI. The objective of this study is to evaluate the association between niacinamide therapy and outcomes in patients with COVID-19-related AKI. METHODS: We implemented a quasi-experimental design with nonrandom, prospective allocation of niacinamide in 201 hospitalized adult patients, excluding those with baseline eGFR
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- 2020
7. Moving beyond COVID-19 Surge—Caring for Patients with Kidney Disease throughout the Pandemic
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Sijie Zheng, Ali Poyan Mehr, Paul Kroupa, Nelson B. Goes, Leonid Pravoverov, Sharina Belani, and Anna V. Asovskaya
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medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Early signs ,medicine.medical_treatment ,030232 urology & nephrology ,030204 cardiovascular system & hematology ,Subspecialty ,Brief Communication ,03 medical and health sciences ,0302 clinical medicine ,Older patients ,Pandemic ,medicine ,Humans ,Intensive care medicine ,Pandemics ,Dialysis ,business.industry ,COVID-19 ,General Medicine ,medicine.disease ,Nephrology ,Kidney Diseases ,Patient Care ,Kidney disorder ,business ,Kidney disease - Abstract
As nephrologists, we have early on recognized the current coronavirus disease 2019 (COVID-19) pandemic to be particularly threatening to the patients we care for in our clinics. Many observations have shown older patients and those with chronic medical comorbidities to be disproportionately at risk for excess morbidity and mortality due to COVID-19 infection (1,2). As a medical subspecialty, nephrologists not only see the most substantial proportion of patients age ≥80 years but also care for the most complex patient population with the highest number of comorbidities (3). Therefore, extensive discussions have been carried out in our community about the potential fallout of COVID-19 infection and the observed or anticipated adverse outcomes. These adverse outcomes include hospitalizations, critical care admission, ESKD, and death in patient’s kidney disorder (4⇓–6). Further, several reports have shown that a high number of patients with COVID-19 infection experience AKI and may require dialysis, potentially increasing demand for available resources beyond capacity (7⇓–9). Several surge-mitigation protocols and COVID-19–related best practice guidelines are now available to nephrologists (10,11). Moving beyond the surge, however, there is substantial uncertainty about the chronic management of patients with kidney disease in the near-term future. When should we time dialysis access placement? Do we place patients at unnecessary risk for “nosocomial” COVID-19 infection by requiring routine laboratory assessment or dialysis access surveillance for primary prevention? Or do we risk a rise in preventable adverse outcomes by dialing back on care considered not essential and thus, failing to identify early signs of medical complications? Answers to some of these questions were already hotly debated before. The COVID-19 pandemic has considerably increased their complexity and uncertainty. Here, we share the Kaiser Permanente Northern California (KPNC) strategy for population-wide management strategies of patients with kidney …
- Published
- 2020
8. The CSL112-2001 trial: Safety and tolerability of multiple doses of CSL112 (apolipoprotein A-I [human]), an intravenous formulation of plasma-derived apolipoprotein A-I, among subjects with moderate renal impairment after acute myocardial infarction
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Megan K. Yee, John Feaster, Majdi Halabi, John J.P. Kastelein, Serge Korjian, Dominick J. Angiolillo, Ravindra L. Mehta, Mathieu Kerneis, Béla Merkely, Danielle Duffy, C. Michael Gibson, Daniel Duerschmied, Ton Oude Ophuis, Basil S. Lewis, Pierluigi Tricoci, Yazan Daaboul, Ali Poyan Mehr, Roxana Mehran, John H. Alexander, Christoph Bode, Beth Israel Deaconess Medical Center [Boston] (BIDMC), Harvard Medical School [Boston] (HMS), University of Amsterdam [Amsterdam] (UvA), Icahn School of Medicine at Mount Sinai [New York] (MSSM), University of Freiburg [Freiburg], Rappaport faculty of Medicine, Technion - Israel Institute of Technology [Haifa], University of California [San Diego] (UC San Diego), University of California, University of Florida [Gainesville] (UF), Semmelweis University of Medicine [Budapest], Vascular Medicine, ACS - Atherosclerosis & ischemic syndromes, and ACS - Pulmonary hypertension & thrombosis
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Male ,medicine.medical_specialty ,Time Factors ,[SDV]Life Sciences [q-bio] ,Myocardial Infarction ,Renal function ,030204 cardiovascular system & hematology ,Placebo ,Gastroenterology ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,Randomized controlled trial ,law ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Myocardial infarction ,Renal Insufficiency, Chronic ,Aged ,Creatinine ,Apolipoprotein A-I ,business.industry ,Acute kidney injury ,Acute Kidney Injury ,medicine.disease ,Intention to Treat Analysis ,3. Good health ,Cholesterol ,Tolerability ,chemistry ,Sample Size ,Female ,Lipoproteins, HDL ,Cardiology and Cardiovascular Medicine ,business ,Biomarkers ,[SDV.MHEP]Life Sciences [q-bio]/Human health and pathology ,Glomerular Filtration Rate ,Kidney disease - Abstract
International audience; BACKGROUND:CSL112 (apolipoprotein A-I [human]) is a plasma-derived apolipoprotein A-I developed for early reduction of cardiovascular risk following an acute myocardial infarction (AMI). The safety of CSL112 among AMI subjects with moderate, stage 3 chronic kidney disease (CKD) is unknown.METHODS:CSL112_2001, a multicenter, placebo-controlled, parallel-group, double-blind, randomized phase 2 trial, enrolled patients with moderate CKD within 7 days following AMI. Enrollment was stratified on the basis of estimated glomerular filtration rate and presence of diabetes requiring treatment. Patients were randomized in a 2:1 ratio to receive 4 weekly infusions of CSL112 6 g or placebo. The co-primary safety end points were renal serious adverse events (SAEs) and acute kidney injury, defined as an increase ≥26.5 μmol/L in baseline serum creatinine for more than 24 hours, during the treatment period.RESULTS:A total of 83 patients were randomized (55 CSL112 vs 28 placebo). No increase in renal SAEs was observed in the CSL112 group compared with placebo (CSL112 = 1 [1.9%], placebo = 4 [14.3%]). Similarly, no increase in acute kidney injury events was observed (CSL112 = 2 [4.0%], placebo = 4 [14.3%]). Rates of other SAEs were similar between groups. CSL112 administration resulted in increases in ApoA-I and cholesterol efflux similar to those observed in patients with AMI and normal renal function or stage 2 CKD enrolled in the ApoA-I Event Reducing in Ischemic Syndromes I trial.CONCLUSIONS:These results demonstrate the acceptable safety of the 6-g dose of CSL112 among AMI subjects with moderate stage 3 CKD and support inclusion of these patients in a phase 3 cardiovascular outcomes trial powered to assess efficacy.
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- 2019
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9. The Glomerular Disease Study and Trial Consortium: A Grassroots Initiative to Foster Collaboration and Innovation
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Isaac E. Stillman, Stewart H. Lecker, Helmut G. Rennke, Tripti Singh, Martin R. Pollak, Neil Roy, Kristi Chau, Roger A. Rodby, Johannes Schlondorff, David J. Friedman, Rima Pai, Maryam Sadeghi-Najafabadi, Mihran Naljayan, Michael J. Germain, Ali Poyan Mehr, and Joseph Messmer
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medicine.medical_specialty ,030232 urology & nephrology ,Review ,030204 cardiovascular system & hematology ,lcsh:RC870-923 ,observational clinical studies ,03 medical and health sciences ,0302 clinical medicine ,Disease registry ,medicine ,Medical history ,Curriculum ,business.industry ,glomerular kidney disease ,nephrology education ,lcsh:Diseases of the genitourinary system. Urology ,medicine.disease ,Clinical trial ,Biorepository ,Nephrology ,Family medicine ,disease registry ,Observational study ,Kidney disorder ,business ,Kidney disease - Abstract
Glomerular kidney disorders account for a significant proportion of chronic kidney disease and end-stage renal disease worldwide. Nevertheless, major obstacles make breakthrough progress in diagnosis and cure an ongoing challenge. Here we report the creation of a “grassroots” initiative that aims to provide new opportunities for nephrologists, pathologists, basic and clinical scientists, patients, and industry partners to collaborate in the field of glomerular kidney disease. Members of the medical community, including trainees, nephrologists, and nephropathologists, can participate in the open-access, Web-based, multidisciplinary clinical video case conferences, which provide “peer-to-peer” exchange of clinical and pathological expertise combined with a formal didactic curriculum. Participants can also join other aspects of the broader initiative. These include the participation in a multisite research study to facilitate enrollment of patients into a longitudinal clinical data and biorepository for glomerular kidney disorders. Items included in this prospective registry include the following: an ontology-based patient medical history, which is regularly updated; interval collection and storage of blood and urine samples; DNA collection; and a contact registry for patients who wish to participate in clinical trials. Participating sites and external scientists can leverage access to the database to pursue genetic, biomarker, epidemiological, and observational clinical effectiveness studies. Patients can independently sign up for a supplementary contact registry to participate in clinical trials if eligible. The broad spectrum of activities within this initiative will foster closer collaboration among trainees, practicing nephrologists, pathologists, and researchers, and may help to overcome some of the barriers to progress in the field of glomerular kidney disease. Keywords: disease registry, glomerular kidney disease, nephrology education, observational clinical studies
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- 2019
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10. De novo NAD+ biosynthetic impairment in acute kidney injury in humans
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Anders H. Berg, Sushrut S. Waikar, Adam Lerner, Eugene P. Rhee, Samir M. Parikh, Matthew R Lynch, Mary E. Trovato, Clary B. Clish, Steven H. Kim, Ravi Thadhani, David E. Leaf, Ali Poyan Mehr, Joseph Messmer, Kamal R. Khabbaz, Charbel C. Khoury, Shoshana J. Herzig, Mei T. Tran, Ajay Kher, Noemie Simon-Tillaux, Kenneth M. Ralto, and Vaughan Washco
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Niacinamide ,0301 basic medicine ,030232 urology & nephrology ,nicotinamide ,Pilot Projects ,Nicotinamide adenine dinucleotide ,Pharmacology ,urologic and male genital diseases ,General Biochemistry, Genetics and Molecular Biology ,Article ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,QPRT ,Biosynthesis ,Ischemia ,NAD+ ,medicine ,Animals ,quinolinate ,Humans ,Pentosyltransferases ,Cardiac Surgical Procedures ,Aged ,2. Zero hunger ,chemistry.chemical_classification ,Nicotinamide ,Tryptophan ,Acute kidney injury ,clinical trial ,General Medicine ,Middle Aged ,Quinolinic Acid ,medicine.disease ,NAD ,Quinolinate ,Biosynthetic Pathways ,Oxidative Stress ,Treatment Outcome ,030104 developmental biology ,Enzyme ,chemistry ,acute kidney injury ,NAD+ kinase ,Homeostasis - Abstract
Nicotinamide adenine dinucleotide (NAD+) extends longevity in experimental organisms, raising interest in its impact on human health. De novo NAD+ biosynthesis from tryptophan is evolutionarily conserved yet considered supplanted among higher species by biosynthesis from nicotinamide (NAM). Here we show that a bottleneck enzyme in de novo biosynthesis, quinolinate phosphoribosyltransferase (QPRT), defends renal NAD+ and mediates resistance to acute kidney injury (AKI). Following murine AKI, renal NAD+ fell, quinolinate rose, and QPRT declined. QPRT+/− mice exhibited higher quinolinate, lower NAD+, and higher AKI susceptibility. Metabolomics suggested an elevated urinary quinolinate/tryptophan ratio (uQ/T) as an indicator of reduced QPRT. Elevated uQ/T predicted AKI and other adverse outcomes in critically ill patients. A phase 1 placebo-controlled study of oral NAM demonstrated a dose-related increase in circulating NAD+ metabolites. NAM was well tolerated and was associated with less AKI. Therefore, impaired NAD+ biosynthesis may be a feature of high-risk hospitalizations for which NAD+ augmentation could be beneficial. Impaired NAD+ biosynthesis may be a common feature of high-risk hospitalizations for which NAD+ augmentation could improve therapeutic outcome.
- Published
- 2018
11. TCT CONNECT-349 Percutaneous Mitral Valve Edge-to-Edge Repair in Patients With Severely Reduced Left Ventricular Ejection Fraction (LVEF ≤20%)
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Samuel Unzek, Camelle Jones, Soundos Moualla, Timothy Byrne, Ligita Centorino, Radha Gopalan, Emrie Tomaiko, Kenith Fang, Hursh Naik, Orazio Amabile, Samuel Butman, Sarah Bertram, Nishant Gupta, Rajkumar Sugumaran, David Biglari, Lee R. Goldberg, Merick Kirshner, Edward Distler, Tony Gaidici, Kwan Lee, Srikanth Seethala, Deepti Taneja, Aneesh Kalya, Arshad Banday, Ali Poyan Mehr, Marium Muzaffar, George Gellert, Thomas Waggoner, Bani Khurana, Divya Ratan Verma, and Mark A. Goldberg
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medicine.medical_specialty ,medicine.anatomical_structure ,Percutaneous ,Ejection fraction ,business.industry ,Mitral valve ,Internal medicine ,medicine ,Cardiology ,In patient ,Edge (geometry) ,Cardiology and Cardiovascular Medicine ,business - Published
- 2020
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12. Functional and molecular identification of a TASK-1 potassium channel regulating chloride secretion through CFTR channels in the shark rectal gland: implications for cystic fibrosis
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Ali Poyan Mehr, William W. Motley, Sarah E. Decker, John N. Forrest, Connor J. Telles, Raymond A. Frizzell, and Alexander W. Peters
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0301 basic medicine ,medicine.medical_specialty ,DNA, Complementary ,Potassium Channels ,Cystic Fibrosis ,Physiology ,Cystic Fibrosis Transmembrane Conductance Regulator ,Nerve Tissue Proteins ,Cystic fibrosis ,Salt Gland ,Xenopus laevis ,03 medical and health sciences ,Potassium Channels, Tandem Pore Domain ,0302 clinical medicine ,Chlorides ,Internal medicine ,medicine ,Animals ,Humans ,Amino Acid Sequence ,Chloride secretion ,Molecular identification ,biology ,Articles ,Cell Biology ,medicine.disease ,Potassium channel ,Cystic fibrosis transmembrane conductance regulator ,Cell biology ,030104 developmental biology ,Endocrinology ,Dogfish ,Oocytes ,Sharks ,biology.protein ,030217 neurology & neurosurgery - Abstract
In the shark rectal gland (SRG), apical chloride secretion through CFTR channels is electrically coupled to a basolateral K+ conductance whose type and molecular identity are unknown. We performed studies in the perfused SRG with 17 K+ channel inhibitors to begin this search. Maximal chloride secretion was markedly inhibited by low-perfusate pH, bupivicaine, anandamide, zinc, quinidine, and quinine, consistent with the properties of an acid-sensitive, four-transmembrane, two-pore-domain K+ channel (4TM-K2P). Using PCR with degenerate primers to this family, we identified a TASK-1 fragment in shark rectal gland, brain, gill, and kidney. Using 5′ and 3′ rapid amplification of cDNA ends PCR and genomic walking, we cloned the full-length shark gene (1,282 bp), whose open reading frame encodes a protein of 375 amino acids that was 80% identical to the human TASK-1 protein. We expressed shark and human TASK-1 cRNA in Xenopus oocytes and characterized these channels using two-electrode voltage clamping. Both channels had identical current-voltage relationships (outward rectifying) and a reversal potential of −90 mV. Both were inhibited by quinine, bupivicaine, and acidic pH. The pKa for current inhibition was 7.75 for shark TASK-1 vs. 7.37 for human TASK-1, values similar to the arterial pH for each species. We identified this protein in SRG by Western blot and confocal immunofluorescent microscopy and detected the protein in SRG and human airway cells. Shark TASK-1 is the major K+ channel coupled to chloride secretion in the SRG, is the oldest 4TM 2P family member identified, and is the first TASK-1 channel identified to play a role in setting the driving force for chloride secretion in epithelia. The detection of this potassium channel in mammalian lung tissue has implications for human biology and disease.
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- 2016
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13. PPARγ-Coactivator-1α, Nicotinamide Adenine Dinucleotide and Renal Stress Resistance
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Samir M. Parikh and Ali Poyan Mehr
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0301 basic medicine ,medicine.medical_specialty ,Kidney ,Nicotinamide ,business.industry ,Acute kidney injury ,Mitochondrion ,Nicotinamide adenine dinucleotide ,medicine.disease ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Mitochondrial biogenesis ,Internal medicine ,medicine ,NAD+ kinase ,business ,Niacin - Abstract
With one of the highest mitochondrial densities in the body, the kidneys consume approximately 10% of total oxygen while constituting 0.5% of body mass. Renal respiration is linear to solute extraction, linking oxidative metabolism directly to tubular function. This fundamental role of mitochondria in renal health may become an “Achilles heel” under duress. Acute kidney injury (AKI) related to each major class of stressor - inflammation, ischemia, and toxins - exhibits early and prominent mitochondrial injury. The mitochondrial biogenesis regulator, PPARγ-coactivator-1α (PGC1α), may confer tubular protection against these stressors. Recent work proposes that renal PGC1α directly increases levels of nicotinamide adenine dinucleotide (NAD+), an essential co-factor for energy metabolism that has lately been proposed as an anti-aging factor. This mini-review summarizes recent studies on AKI, PGC1α, and NAD+ that identify a direct mechanism between the regulation of metabolic health and the ability to resist renal stressors.
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- 2017
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14. COMPARISON OF LONG-TERM OUTCOMES WITH BIODEGRADABLE POLYMER DRUG ELUTING STENTS AND DURABLE POLYMER DRUG ELUTING STENTS: AN UPDATED META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS
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Ali Poyan Mehr, Anantharam Kalya, Radha Gopalan, Samuel Butman, Samuel Unzek Freiman, Ligita Centorino, Nickalaus L. Gramze, Robert T. Hurst, Arshad Banday, Francisco A. Arabia, Nachiket Patel, Moses Ashukem, Byomesh Tripathi, Martha Gulati, Michael Kost, Firas Abbas, Wilber Su, Katheryne Marchbanks, Rajkumar Sugumaran, David Biglari, Divya Ratan Verma, and Peter Weiss
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Drug ,medicine.medical_specialty ,Web of science ,business.industry ,media_common.quotation_subject ,Biodegradable polymer ,law.invention ,Randomized controlled trial ,law ,Meta-analysis ,Durable polymer ,Long term outcomes ,Medicine ,Cardiology and Cardiovascular Medicine ,business ,Intensive care medicine ,media_common - Abstract
Long term outcomes of biodegradable polymer drug-eluting stents (BP-DES) compared to durable polymer drug-eluting stents (DP-DES), are not well described. A comprehensive search in clinicalTrials.gov, PubMed, EBSCO, Web of Science, google scholar and Ovid was performed for RCTs comparing BP-DES and
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- 2020
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15. Physiology of Local Renin-Angiotensin Systems
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Martin Paul, Reinhold Kreutz, and Ali Poyan Mehr
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Physiology ,Cell growth ,Transgene ,Endocrine System ,General Medicine ,Biology ,medicine.disease ,Renin-Angiotensin System ,Diabetic nephropathy ,Paracrine signalling ,Mediator ,Physiology (medical) ,Renin–angiotensin system ,medicine ,Animals ,Humans ,Autocrine signalling ,Receptor ,Molecular Biology - Abstract
Since the first identification of renin by Tigerstedt and Bergmann in 1898, the renin-angiotensin system (RAS) has been extensively studied. The current view of the system is characterized by an increased complexity, as evidenced by the discovery of new functional components and pathways of the RAS. In recent years, the pathophysiological implications of the system have been the main focus of attention, and inhibitors of the RAS such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin (ANG) II receptor blockers have become important clinical tools in the treatment of cardiovascular and renal diseases such as hypertension, heart failure, and diabetic nephropathy. Nevertheless, the tissue RAS also plays an important role in mediating diverse physiological functions. These focus not only on the classical actions of ANG on the cardiovascular system, namely, the maintenance of cardiovascular homeostasis, but also on other functions. Recently, the research efforts studying these noncardiovascular effects of the RAS have intensified, and a large body of data are now available to support the existence of numerous organ-based RAS exerting diverse physiological effects. ANG II has direct effects at the cellular level and can influence, for example, cell growth and differentiation, but also may play a role as a mediator of apoptosis. These universal paracrine and autocrine actions may be important in many organ systems and can mediate important physiological stimuli. Transgenic overexpression and knock-out strategies of RAS genes in animals have also shown a central functional role of the RAS in prenatal development. Taken together, these findings may become increasingly important in the study of organ physiology but also for a fresh look at the implications of these findings for organ pathophysiology.
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- 2006
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16. Genetic Loci Contribute to the Progression of Vascular and Cardiac Hypertrophy in Salt-Sensitive Spontaneous Hypertension
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Peter Kossmehl, Anja-Kristin Siegel, Sibylle Rademacher, Michael Planert, Reinhold Kreutz, Markus Wehland, Ali Poyan Mehr, and Monika Stoll
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medicine.medical_specialty ,Genotype ,Genetic Linkage ,Blood Pressure ,Cardiomegaly ,Chromosome 9 ,Quantitative trait locus ,Biology ,Rats, Inbred WKY ,Muscle hypertrophy ,Spontaneously hypertensive rat ,Fibrosis ,Rats, Inbred SHR ,Internal medicine ,medicine.artery ,medicine ,Animals ,cardiovascular diseases ,Aorta ,Rats, Inbred Dahl ,Chromosome Mapping ,Sodium, Dietary ,medicine.disease ,Rats ,Phenotype ,Endocrinology ,Blood pressure ,Salt sensitivity ,Disease Progression ,Cardiology ,Hypertrophy, Left Ventricular ,Cardiology and Cardiovascular Medicine - Abstract
Objective— The salt-sensitive Dahl rat and the spontaneously hypertensive rat develop comparable spontaneous hypertension on a low-salt diet, whereas only the salt-sensitive Dahl rat strain develops a striking increase in blood pressure and cardiovascular hypertrophy on a high-salt diet. We set out to identify quantitative trait loci (QTLs) contributing to the progression of salt-induced organ damage in hypertension by studying an F 2 population derived from both strains. Methods and Results— We determined systolic blood pressure (SBP), vascular aortic hypertrophy (AH), cardiac left ventricular (LV) hypertrophy (LVH), and LV fibrosis in 230 male F 2 -animals on a high-salt diet. A strong correlation between AH and LVH was found ( r =0.58, P Conclusions— This study demonstrates a strong correlation between AH and LVH in salt-sensitive hypertension and identifies QTLs contributing to the progression of cardiovascular hypertrophy in this condition.
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- 2003
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17. THE SAFETY AND TOLERABILITY OF MULTIPLE DOSE ADMINISTRATION OF CSL112, AN INTRAVENOUS FORMULATION OF PLASMA-DERIVED APOA-I, AMONG SUBJECTS WITH MODERATE RENAL IMPAIRMENT AFTER ACUTE MYOCARDIAL INFARCTION
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Danielle Duffy, Christoph Bode, Mathieu Kerneis, Megan Yee, John Feaster, Basil Lewis, John Kastelein, C. Michael Gibson, Yazan Daaboul, Roxana Mehran, Daniel Duerschmied, Pierluigi Tricoci, Dominick J. Angiolillo, John Alexander, Ali Poyan Mehr, Ton Oude Ophius, Bela Merkely, Serge Korjian, Majdi Halabi, and Ravindra Mehta
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0301 basic medicine ,medicine.medical_specialty ,Apolipoprotein B ,Multiple dose ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Medicine ,cardiovascular diseases ,Myocardial infarction ,biology ,business.industry ,Plasma derived ,Cholesterol ,Intravenous Infusions ,medicine.disease ,030104 developmental biology ,chemistry ,Tolerability ,030220 oncology & carcinogenesis ,biology.protein ,Cardiology ,lipids (amino acids, peptides, and proteins) ,Cardiology and Cardiovascular Medicine ,business - Abstract
CSL112 is plasma-derived apolipoprotein A-I (apoA-I), currently in development for early reduction of cardiovascular risk after acute myocardial infarction (AMI). The AEGIS-I trial demonstrated renal and hepatic safety and elevations in cholesterol efflux with 4 weekly intravenous infusions of 2g or
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- 2018
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18. Human kidney proximal tubule-on-a-chip for drug transport and nephrotoxicity assessment
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Seyoon Chung, Kahp-Yang Suh, Geraldine A. Hamilton, Donald E. Ingber, Lori McPartlin, Ali Poyan Mehr, and Kyung-Jin Jang
- Subjects
Brush border ,Biophysics ,Drug Evaluation, Preclinical ,Biology ,Biochemistry ,Organ-on-a-chip ,Nephrotoxicity ,Kidney Tubules, Proximal ,In vivo ,Albumins ,medicine ,Humans ,ATP Binding Cassette Transporter, Subfamily B, Member 1 ,Kidney ,Biological Transport ,Epithelial Cells ,Anatomy ,Microfluidic Analytical Techniques ,Alkaline Phosphatase ,Epithelium ,Cell biology ,medicine.anatomical_structure ,Glucose ,Microscopy, Fluorescence ,Cell culture ,Alkaline phosphatase ,Cisplatin - Abstract
Kidney toxicity is one of the most frequent adverse events reported during drug development. The lack of accurate predictive cell culture models and the unreliability of animal studies have created a need for better approaches to recapitulate kidney function in vitro. Here, we describe a microfluidic device lined by living human kidney epithelial cells exposed to fluidic flow that mimics key functions of the human kidney proximal tubule. Primary kidney epithelial cells isolated from human proximal tubule are cultured on the upper surface of an extracellular matrix-coated, porous, polyester membrane that splits the main channel of the device into two adjacent channels, thereby creating an apical 'luminal' channel and a basal 'interstitial' space. Exposure of the epithelial monolayer to an apical fluid shear stress (0.2 dyne cm(-2)) that mimics that found in living kidney tubules results in enhanced epithelial cell polarization and primary cilia formation compared to traditional Transwell culture systems. The cells also exhibited significantly greater albumin transport, glucose reabsorption, and brush border alkaline phosphatase activity. Importantly, cisplatin toxicity and Pgp efflux transporter activity measured on-chip more closely mimic the in vivo responses than results obtained with cells maintained under conventional culture conditions. While past studies have analyzed kidney tubular cells cultured under flow conditions in vitro, this is the first report of a toxicity study using primary human kidney proximal tubular epithelial cells in a microfluidic 'organ-on-a-chip' microdevice. The in vivo-like pathophysiology observed in this system suggests that it might serve as a useful tool for evaluating human-relevant renal toxicity in preclinical safety studies.
- Published
- 2013
19. Early onset albuminuria in Dahl rats is a polygenetic trait that is independent from salt loading
- Author
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Peter Kossmehl, Reinhold Kreutz, Anja-Kristin Siegel, Ralph Plehm, Angela Schulz, Emile de Heer, Jan A. Bruijn, and Ali Poyan Mehr
- Subjects
Male ,Multifactorial Inheritance ,medicine.medical_specialty ,Urinary albumin ,Genotype ,Genetic Linkage ,Physiology ,Quantitative Trait Loci ,Blood Pressure ,Biology ,Quantitative trait locus ,Excretion ,Quantitative Trait, Heritable ,Rats, Inbred SHR ,Internal medicine ,Genetics ,medicine ,Albuminuria ,Animals ,Sodium Chloride, Dietary ,Crosses, Genetic ,Salt loading ,Early onset ,Genome ,Rats, Inbred Dahl ,Chromosome Mapping ,Rats ,Phenotype ,Endocrinology ,Female ,medicine.symptom - Abstract
The aim of the study was to characterize the genetic basis for the early onset of increased urinary albumin excretion (UAE) observed in the salt-sensitive Dahl rat (SS). We first characterized blood pressures and UAE values in adult SS compared with the spontaneously hypertensive rat (SHR) strain. Blood pressure measurements by radiotelemetry at 14 wk demonstrated similar spontaneous hypertension in both strains on a low-sodium diet containing 0.2% NaCl by weight, whereas UAE was markedly increased in SS compared with SHR (253.07 ± 68.39 vs. 1.65 ± 1.09 mg/24 h, P < 0.0001). Analysis of UAE in young animals of both strains fed a low-sodium diet demonstrated that UAE is elevated in SS as early as 4 wk of age ( P < 0.0001), when ultrastructural evaluation of glomeruli by electron microscopy appears still normal. At 8 wk SS demonstrated a 280-fold elevated UAE compared with SHR ( P < 0.0001). Consequently, to identify quantitative trait loci (QTLs) contributing to salt-independent early manifestation of increased UAE in the SS rat, we performed genome-wide linkage and QTL mapping analysis in a young F2population derived from the two contrasting strains. UAE was determined in 539 F2animals at 8 wk. We identified seven suggestive or significant UAE QTLs on rat chromosomes (RNO) RNO2, RNO6, RNO8, RNO9, RNO10, RNO11, and RNO19, accounting together for 34% of the overall variance of UAE in this F2population. Thus early onset albuminuria in the SS rat is under polygenetic influence and independent from salt loading.
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