The Tulane Medical Center is a hospital located in New Orleans, Louisiana. The Tulane Medical Center has centers covering nearly all major specialties of medicine, and is the primary teaching hospital for the Tulane University School of Medicine. The hospital is jointly owned by Hospital Corporation of America and Tulane University . Wikipedia.
Varma N.,Cleveland Clinic |
Epstein A.E.,University of Pennsylvania |
Irimpen A.,Tulane University Medical Center |
Schweikert R.,Akron General Medical Center |
Love C.,Ohio State University
Circulation | Year: 2010
Background-: Monitoring implantable cardiac device function and patient condition is important. The Lumos-T Safely Reduces Routine Office Device Follow-Up (TRUST) trial tested the hypothesis that remote home monitoring with automatic daily surveillance (HM) is safe and effective for implantable cardioverter-defibrillator follow-up for 1 year and enables rapid physician evaluation of significant events. Methods and results-: In total, 1339 patients were randomized 2:1 to HM or conventional follow-up. Follow-up checks occurred at 3, 6, 9, 12, and 15 months after implantation. HM was used before office visits at 3 and 15 months in the HM group. At 6, 9, and 12 months, HM only was used but was followed by office visits if necessary. Conventional patients were evaluated with office visits only. Scheduled office visits and unscheduled evaluations, incidence of morbidity, and time elapsed from first event occurrence in each patient to physician evaluation were tracked for each group. HM and conventional patients were similar (age, 63.3±12.8 versus 64.0±12.1 years; gender, 72.0% versus 73.1% male; New York Heart Association class II, 55.9% versus 60.4%; pathology: left ventricular ejection fraction, 29.0±10.7% versus 28.5±9.8%; coronary artery disease, 64.8% versus 71.7%; primary prevention indication, 72.2% versus 73.8%; and dual-chamber implants, 57.8% versus 56.6%). HM reduced total in-hospital device evaluations by 45% without affecting morbidity. In the HM group, 85.8% of all 6-, 9-, and 12-month follow-ups were performed remotely only, indicating that HM provided sufficient assessment in the majority. Median time to evaluation was <2 days in the HM group compared with 36 days in the conventional group (P<0.001) for all arrhythmic events. Conclusions-: HM is safe and allows more rapid detection of actionable events compared with conventional monitoring in patients with implantable electronic cardiac devices. © 2010 American Heart Association, Inc.
Abd Elmageed Z.Y.,Tulane University Medical Center |
Naura A.S.,Louisiana State University Health Sciences Center |
Errami Y.,Louisiana State University Health Sciences Center |
Zerfaoui M.,University of Alabama at Birmingham
Cellular Signalling | Year: 2012
Post-transcriptional modification of proteins is crucial for balancing protein structure and function in many biological processes. The addition of polymers of adenosine diphosphate (ADP)-ribose (PAR), which are synthesized by PAR polymerases (PARPs) from nicotinamide adenine dinucleotide (NAD), is one such distinctive post-translational modification. PARP-1, the best characterized of the 17-member PARP family, is considered a key isoform responsible for poly(ADP-ribosyl)ation of several nuclear proteins. ADP-ribose polymers add a highly negative charge to their target proteins, resulting in a modification of their activities and functions. PARPs not only participate in regulating cell survival and cell death programs, but are also involved in other biological functions with which novel members of the PARP family have been shown to be involved. Among such functions are transcription regulation, telomere cohesion and mitotic spindle formation during cell division, and intracellular energy metabolism. Recent work from our laboratory and others has highlighted the novel role of PARP-1 in regulating the intracellular trafficking of key cellular proteins such as p53 and nuclear factor-kappa B (NF-κB). Recent literature has revealed that ADP-ribosylation reactions may play important roles in cellular trafficking during inflammation, cell death, and DNA repair. This review will summarize recent findings and concepts linking the role of PARP enzymes and their poly-ADP-ribosylation activity in the regulation of intracellular transport processes. A special focus is placed on the proposed molecular mechanisms involved in such transport processes as the functional significance of PARylation of p53, NF-κB, and high-mobility group protein box 1. © 2011 Elsevier Inc.
Gimble J.M.,Louisiana State University |
Bunnell B.A.,Tulane University Medical Center |
Chiu E.S.,Tulane University Medical Center |
Guilak F.,Duke University
Stem Cells | Year: 2011
Subcutaneous fat has emerged as an alternative tissue source for stromal/stem cells in regenerative medicine. Over the past decade, international research efforts have established a wealth of basic science and preclinical evidence regarding the differentiation potential and regenerative properties of both freshly processed, heterogeneous stromal vascular fraction cells and culture expanded, relatively homogeneous adipose-derived stromal/stem cells. the stage has been set for clinicians to translate adipose-derived cells from the bench to the bedside; however, this process will involve "development" steps that fall outside of traditional "hypothesis-driven, mechanism-based'' paradigm. This concise review examines the next stages of the development process for therapeutic applications of adipose-derived cells and highlights the current state of the art regarding clinical trials. It is recommended that the experiments addressing these issues be reported comprehensively in the peer-review literature. This transparency will accelerate the standardization and reproducibility of adipose-derived cell therapies with respect to their efficacy and safety. © AlphaMed Press.
Li E.,Saint Joseph's University |
Wimley W.C.,Tulane University Medical Center |
Hristova K.,Johns Hopkins University
Biochimica et Biophysica Acta - Biomembranes | Year: 2012
Studies of the dimerization of transmembrane (TM) helices have been ongoing for many years now, and have provided clues to the fundamental principles behind membrane protein (MP) folding. Our understanding of TM helix dimerization has been dominated by the idea that sequence motifs, simple recognizable amino acid sequences that drive lateral interaction, can be used to explain and predict the lateral interactions between TM helices in membrane proteins. But as more and more unique interacting helices are characterized, it is becoming clear that the sequence motif paradigm is incomplete. Experimental evidence suggests that the search for sequence motifs, as mediators of TM helix dimerization, cannot solve the membrane protein folding problem alone. Here we review the current understanding in the field, as it has evolved from the paradigm of sequence motifs into a view in which the interactions between TM helices are much more complex. This article is part of a Special Issue entitled: Membrane protein structure and function. © 2011 Elsevier B.V.
Morava E.,Tulane University Medical Center |
Morava E.,Radboud University Nijmegen
Molecular Genetics and Metabolism | Year: 2014
We recently redefined phosphoglucomutase-1 deficiency not only as an enzyme defect, involved in normal glycogen metabolism, but also an inborn error of protein glycosylation. Phosphoglucomutase-1 is a key enzyme in glycolysis and glycogenesis by catalyzing in the bidirectional transfer of phosphate from position 1 to 6 on glucose. Glucose-1-P and UDP-glucose are closely linked to galactose metabolism. Normal PGM1 activity is important for effective glycolysis during fasting. Activated glucose and galactose are essential for normal protein glycosylation. The complex defect involving abnormal concentrations of activated sugars leads to hypoglycemia and two major phenotypic presentations, one with primary muscle involvement and the other with severe multisystem disease. The multisystem phenotype includes growth delay and malformations, like cleft palate or uvula, and liver, endocrine and heart function with possible cardiomyopathy. The patients have normal intelligence. Decreased transferrin galactosylation is a characteristic finding on mass spectrometry. Previous in vitro studies in patient fibroblasts showed an improvement of glycosylation on galactose supplements. Four patients with PGM1 deficiency have been trialed on d-galactose (compassionate use), and showed improvement of serum transferrin hypoglycosylation. There was a parallel improvement of liver function, endocrine abnormalities and a decrease in the frequency of hypoglycemic episodes. No side effects have been observed. Galactose supplementation didn't seem to resolve all clinical symptoms. Adding complex carbohydrates showed an additional clinical amelioration. Based on the available clinical data we suggest to consider the use of 0.5-1. g/kg/day d-galactose and maximum 50. g/day oral galactose therapy in PGM1-CDG. The existing data on galactose therapy have to be viewed as preliminary observations. A prospective multicenter trial is ongoing to evaluate the efficacy and optimal d-galactose dose of galactose supplementation. © 2014 Elsevier Inc.
Fonseca V.A.,Tulane University Medical Center
Clinical Therapeutics | Year: 2014
Background Suboptimal blood glucose control among patients with type 2 diabetes continues to support the need for new pharmacologic approaches. Objective The purpose of this commentary was to highlight newly available and soon-to-be available agents that are promising tools for targeting specific pathophysiologic pathways in the management of diabetes. Methods Published evidence to support the application of novel incretin-based therapies, dipeptidyl peptidase (DPP)-4 inhibitors, sodium-glucose cotransporter (SGLT)-2 inhibitors, other oral agents and insulins for managing specific aspects of type 2 diabetes, as well as disadvantages associated with those novel medications, are discussed. Results Several new glucagon-like peptide (GLP)-1 receptor agonists with different time frames of action, although each has unique advantages and disadvantages, have been through clinical trials. Examples of these are lixisenatide and albiglutide. Currently available DPP-4 inhibitor agents, important for inhibiting the breakdown of endogenous GLP-1, have not been associated with weight gain or hypoglycemia. SGLT-2 inhibitors, which do not depend on insulin secretion or insulin action, may be advantageous in that they appear to be broadly efficacious at all stages of diabetes. New insulin analogues, such as degludec and U-500, improve glycemic control without contributing to hypoglycemia. Conclusions Advances in pharmacologic options offer the promise of improving glycemic control for longer periods, with limited glycemic fluctuations, hypoglycemia, and weight gain. However, the effectiveness of these agents ultimately depends on their availability to providers managing the health care of patients at high risk for poor diabetes outcomes and patients' use of them as directed. Long-term effectiveness and safety trials are ongoing. © 2014 Elsevier HS Journals, Inc.
Richey L.E.,Tulane University Medical Center |
Halperin J.,Tulane University Medical Center
American Journal of the Medical Sciences | Year: 2013
The clinical spectrum of acute human immunodeficiency virus (HIV) infection, a common clinical syndrome, may range from asymptomatic to a severe illness. The purpose of this review is to increase awareness of this syndrome, which is rarely suspected and often missed in clinical care settings, and provide an informative reference for primary care providers. The diagnosis of acute HIV infection is important for both patient care and public health concerns. In this article, the epidemiology, pathophysiology, clinical presentation, diagnosis and treatment of acute HIV infection are reviewed. © Copyright 2013 Southern Society for Clinical Investigation.
Killackey M.,Tulane University Medical Center
Southern Medical Journal | Year: 2010
Obesity is a worldwide epidemic and public health crisis associated with severe comorbidity leading to end organ dysfunction and poorer transplant outcome. Large population studies show decreased patient and graft survival in obese kidney transplant patients. Despite the poorer outcomes, kidney transplant is considered because of the survival benefit as compared to the wait-listed dialysis patients. In liver transplantation, the benefit of transplant as compared to remaining on the list is obvious because there is no viable liver dialysis at this time.Obesity in potential organ donors impacts both medical and surgical issues. Obesity-related kidney disease affects both the remaining and transplanted kidney. Pancreas donor organs are associated with decreased early graft survival. Liver donor organs with significant steatosis lead to an increased risk for delayed function or nonfunction of the organ. Immunosuppressive drugs with variable lipophilicity and altered volume of distribution can greatly affect the therapeutic usefulness of these drugs.Transplant candidates benefit from a multidisciplinary team approach to their care. As the epidemic progresses and less invasive treatments for metabolic surgery evolve, we are likely to see more patients lose weight before transplant as we continue to strive for improved outcomes. Copyright © 2010 by The Southern Medical Association.
Feng M.-G.,Tulane University Medical Center |
Navar L.G.,Tulane University Medical Center
American Journal of Physiology - Renal Physiology | Year: 2010
Adenosine is an important paracrine agent regulating renal vascular tone via adenosine A1 and A2 receptors. While A2B receptor message and protein have been localized to preglomerular vessels, functional evidence on the role of A2B receptors in mediating the vasodilator action of adenosine on afferent arterioles is not available. The present study determined the role of A2B receptors in mediating the afferent arteriolar dilation and compared the effects of A2B and A2A receptor blockade on afferent arterioles. We used the rat in vitro blood-perfused juxtamedullary nephron technique combined with videomicroscopy. Single afferent arterioles of Sprague-Dawley rats were visualized and superfused with solutions containing adenosine or adenosine A2 receptor agonist (CV-1808) along with adenosine A2B and A2A receptor blockers. Adenosine (10 μmol/l) caused modest constriction and subsequent superfusion with SCH-58261 (SCH), an A2A receptor blocker, at concentrations up 10 μmol/l elicited only slight additional decreases in afferent arteriolar diameter with maximum effect at a concentration of 1 μmol/l (-11.0 ± 2.5%, n = 6, P < 0.05). However, superfusion of adenosine-treated vessels with MRS-1754 (MRS), an A2B receptor blocker, elicited greater decreases in afferent arteriolar diameter (-26.0 ± 4.7%, n = 5, P < 0.01). SCH did not significantly augment the adenosine-mediated afferent constriction elicited by MRS; however, adding MRS after SCH caused further significant vasoconstriction. Superfusion with CV-1808 dilated afferent arterioles (17.2 ± 2.4%, n = 6, P < 0.01). This effect was markedly attenuated by MRS (-22.6 ± 2.0%, n = 5, P < 0.01) but only slightly reduced by SCH (-9.0 ± 1.1%, n = 5, P < 0.05) and completely prevented by adding MRS after SCH (-24.7 ± 1.8%, n = 5, P < 0.01). These results indicate that, while both A2A and A 2B receptors are functionally expressed in juxtamedullary afferent arterioles, the powerful vasodilating action of adenosine predominantly involves A2B receptor activation, which counteracts A1 receptor-mediated vasoconstriction. Copyright © 2010 the American Physiological Society.
Feng M.-G.,Tulane University Medical Center |
Prieto M.C.,Tulane University Medical Center |
Navar L.G.,Tulane University Medical Center
American Journal of Physiology - Renal Physiology | Year: 2012
Nebivolol is a β1-adrenergic blocker that also elicits renal vasodilation and increases the glomerular filtration rate (GFR). However, its direct actions on the renal microvasculature and vasodilator mechanism have not been established. We used the in vitro blood-perfused juxtamedullary nephron technique to determine the vasodilator effects of nebivolol and to test the hypothesis that nebivolol induces vasodilation of renal afferent arterioles via an nitric oxide synthase (NOS)/nitric oxide (NO)/soluble guanylate cyclase (sGC)/cGMP pathway and the afferent arteriolar vasodilation effect may be mediated through the release of NO by activation of NOS via a β3-adrenoceptor-dependent mechanism. Juxtamedullary nephrons were superfused with nebivolol either alone or combined with the sGC inhibitor 1H-[1,2,4]oxadiazolo[ 4,3-a]quinoxalin-1-one (ODQ) or the NOS inhibitor Nω-nitro-Larginine (L-NNA) or the β-blockers metoprolol (β1), butoxamine (β2), and SR59230A (β3). Nebivolol (100 μmol/l) markedly increased afferent and efferent arteriolar diameters by 18.9 ± 3.0 and 15.8 ± 1.8%. Pretreatment with L-NNA (1,000 μmol/l) or ODQ (10 μmol/l) decreased afferent vasodilator diameters and prevented the vasodilator effects of nebivolol (2.0 ± 0.2 and 2.4 ± 0.6%). Metoprolol did not elicit significant changes in afferent vasodilator diameters and did not prevent the effects of nebivolol to vasodilate afferent arterioles. However, treatment with SR59230A, but not butoxamine, markedly attenuated the vasodilation responses to nebivolol. Using a monoclonal antibody to β3-receptors revealed predominant immunostaining on vascular and glomerular endothelial cells. These data indicate that nebivolol vasodilates both afferent and efferent arterioles and that the afferent vasodilator effect is via a mechanism that is independent of β1-receptors but is predominantly mediated via a NOS/NO/sGC/ cGMP-dependent mechanisms initiated by activation of endothelial β3-receptors. © 2012 the American Physiological Society.