New Orleans, LA, United States

Tulane University
New Orleans, LA, United States

Tulane University of Louisiana is a private, nonsectarian research university located in New Orleans, Louisiana, United States. Founded as a public medical college in 1834, the school grew into a comprehensive university in 1847 and was eventually privatized under the endowments of Paul Tulane and Josephine Louise Newcomb in 1884. Tulane is a member of the Association of American Universities. Wikipedia.

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Wang Y.,Tulane University | Grayson S.M.,Tulane University
Advanced Drug Delivery Reviews | Year: 2012

Amphiphilic polymers are particularly useful for drug delivery because of their ability to self-assemble into discrete aggregates. While this behavior has been studied in depth for simple linear block copolymer amphiphiles, recent advances in synthetic methodologies have provided efficient routes to amphiphilic polymers with more complex architecture, including dendrimers, hyperbranched polymers, star polymers, and cyclic polymers. These architectures can impart unique advantages, such as increased stability, on their micellar aggregates. Herein the different strategies for preparing these complex amphiphiles are described, and the application of their assemblies towards drug delivery are summarized. © 2012 Elsevier B.V.

Daniel J.M.,Tulane University
Hormones and Behavior | Year: 2013

This article is part of a Special Issue "Hormones & Neurotrauma".Estrogens have been shown to be protective agents against neurodegeneration and associated cognitive decline in aging females. However, clinical data have been equivocal as to the benefits to the brain and cognition of estrogen therapy in postmenopausal women. One factor that is proposed to be critical in determining the efficacy of hormone therapy is the timing of its initiation. The critical period or window of opportunity hypothesis proposes that following long-term ovarian hormone deprivation, the brain and cognition become insensitive to exogenously administered estrogens. In contrast, if estrogens are administered during a critical period near the time of cessation of ovarian function, they will exert beneficial effects. The focus of the current review is the examination of evidence from rodent models investigating the critical period hypothesis. A growing body of experimental data indicates that beneficial effects of 17β-estradiol (estradiol) on cognition and on cholinergic function and hippocampal plasticity, both of which have been linked to the ability of estradiol to exert beneficial effects on cognition, are attenuated if estradiol is administered following a period of long-term ovarian hormone deprivation. Further, emerging data implicate loss of estrogen receptor alpha (ERα) in the brain resulting from long-term hormone deprivation as a basis for the existence of the critical period. A unifying model is proposed by which the presence or absence of estrogens during a critical period following the cessation of ovarian function permanently alters the system resulting in decreased or increased risk, respectively, of neurodegeneration and cognitive decline. © 2012 Elsevier Inc.

Wimley W.C.,Tulane University
ACS Chemical Biology | Year: 2010

Antimicrobial peptides (AMPs) have been studied for three decades, and yet a molecular understanding of their mechanism of action is still lacking. Here we summarize current knowledge for both synthetic vesicle experiments and microbe experiments, with a focus on comparisons between the two. Microbial experiments are done at peptide to lipid ratios that are at least 4 orders of magnitude higher than vesicle-based experiments. To close the gap between the two concentration regimes, we propose an "interfacial activity model", which is based on an experimentally testable molecular image of AMPâ€"membrane interactions. The interfacial activity model may be useful in driving engineering and design of novel AMPs. © 2010 American Chemical Society.

Jazwinski S.M.,Tulane University
Biochimica et Biophysica Acta - Molecular Cell Research | Year: 2013

Mitochondria are responsible for generating adenosine triphosphate (ATP) and metabolic intermediates for biosynthesis. These dual functions require the activity of the electron transport chain in the mitochondrial inner membrane. The performance of these electron carriers is imperfect, resulting in release of damaging reactive oxygen species. Thus, continued mitochondrial activity requires maintenance. There are numerous means by which this quality control is ensured. Autophagy and selective mitophagy are among them. However, the cell inevitably must compensate for declining quality control by activating a variety of adaptations that entail the signaling of the presence of mitochondrial dysfunction to the nucleus. The best known of these is the retrograde response. This signaling pathway is triggered by the loss of mitochondrial membrane potential, which engages a series of signal transduction proteins, and it culminates in the induction of a broad array of nuclear target genes. One of the hallmarks of the retrograde response is its capacity to extend the replicative life span of the cell. The retrograde signaling pathway interacts with several other signaling pathways, such as target of rapamycin (TOR) and ceramide signaling. All of these pathways respond to stress, including metabolic stress. The retrograde response is also linked to both autophagy and mitophagy at the gene and protein activation levels. Another quality control mechanism involves age-asymmetry in the segregation of dysfunctional mitochondria. One of the processes that impinge on this age-asymmetry is related to biogenesis of the organelle. Altogether, it is apparent that mitochondrial quality control constitutes a complex network of processes, whose full understanding will require a systems approach. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids. © 2012 Elsevier B.V.

Anbalagan M.,Tulane University
Nuclear receptor signaling | Year: 2012

Nuclear receptors (NR) impact a myriad of physiological processes including homeostasis, reproduction, development, and metabolism. NRs are regulated by post-translational modifications (PTM) that markedly impact receptor function. Recent studies have identified NR PTMs that are involved in the onset and progression of human diseases, including cancer. The majority of evidence linking NR PTMs with disease has been demonstrated for phosphorylation, acetylation and sumoylation of androgen receptor (AR), estrogen receptor α (ERα), glucocorticoid receptor (GR) and peroxisome proliferator activated receptor γ (PPARγ). Phosphorylation of AR has been associated with hormone refractory prostate cancer and decreased disease-specific survival. AR acetylation and sumoylation increased growth of prostate cancer tumor models. AR phosphorylation reduced the toxicity of the expanded polyglutamine AR in Kennedy's Disease as a consequence of reduced ligand binding. A comprehensive evaluation of ERα phosphorylation in breast cancer revealed several sites associated with better clinical outcome to tamoxifen therapy, whereas other phosphorylation sites were associated with poorer clinical outcome. ERα acetylation and sumoylation may also have predictive value for breast cancer. GR phosphorylation and acetylation impact GR responsiveness to glucocorticoids that are used as anti-inflammatory drugs. PPARγ phosphorylation can regulate the balance between growth and differentiation in adipose tissue that is linked to obesity and insulin resistance. Sumoylation of PPARγ is linked to repression of inflammatory genes important in patients with inflammatory diseases. NR PTMs provide an additional measure of NR function that can be used as both biomarkers of disease progression, and predictive markers for patient response to NR-directed treatments.

Kassan M.,Tulane University
Arteriosclerosis, thrombosis, and vascular biology | Year: 2012

Cardiac damage and vascular dysfunction are major causes of morbidity and mortality in hypertension. In the present study, we explored the beneficial therapeutic effect of endoplasmic reticulum (ER) stress inhibition on cardiac damage and vascular dysfunction in hypertension. Mice were infused with angiotensin II (400 ng/kg per minute) with or without ER stress inhibitors (taurine-conjugated ursodeoxycholic acid and 4-phenylbutyric acid) for 2 weeks. Mice infused with angiotensin II displayed an increase in blood pressure, cardiac hypertrophy and fibrosis associated with enhanced collagen I content, transforming growth factor-β1 (TGF-β1) activity, and ER stress markers, which were blunted after ER stress inhibition. Hypertension induced ER stress in aorta and mesenteric resistance arteries (MRA), enhanced TGF-β1 activity in aorta but not in MRA, and reduced endothelial NO synthase phosphorylation and endothelium-dependent relaxation (EDR) in aorta and MRA. The inhibition of ER stress significantly reduced TGF-β1 activity, enhanced endothelial NO synthase phosphorylation, and improved EDR. The inhibition of TGF-β1 pathway improved EDR in aorta but not in MRA, whereas the reduction in reactive oxygen species levels ameliorated EDR in MRA only. Infusion of tunicamycin in control mice induced ER stress in aorta and MRA, and reduced EDR by a TGF-β1-dependent mechanism in aorta and reactive oxygen species-dependent mechanism in MRA. ER stress inhibition reduces cardiac damage and improves vascular function in hypertension. Therefore, ER stress could be a potential target for cardiovascular diseases.

Agency: NSF | Branch: Continuing grant | Program: | Phase: QIS - Quantum Information Scie | Award Amount: 98.04K | Year: 2017

Superconducting quantum devices -- micrometer-scale circuits which are cooled to a few hundredths of a degree above absolute zero, where all electrical resistance vanishes -- are one of the most promising technologies for the future of computing. For many years, research in superconducting quantum bits (or qubits) was focused mainly on reducing noise in individual devices, but recent breakthroughs in coherence have made much larger circuits a reality, and new devices will soon reach a level of complexity where it is impossible to simulate them with regular computers. The PI will propose and coordinate new designs, experiments and applications for these devices that expand the frontiers of quantum computing. His research will study new methods for simulating exotic states of matter, correcting errors that occur from random noise, and using these qubits to more efficiently solve hard optimization problems. Graduate and undergraduate students will be trained and supported by the funding for this project. This program will also help the PI promote his research to aid commercial efforts to build quantum computers. The PI will also work in Tulane Universitys summer outreach program, to help attract middle and high school students to careers in science.

The scientific goals of this program are threefold. First, the PIs work will help researchers use photons trapped by superconducting qubits to simulate exotic states of matter, providing a new platform for testing predictions in quantum many-body physics. Second, the PI will explore applications of engineered dissipation, carefully tuned noise sources which can passively and automatically cancel out unwanted errors, and potentially speed up the process of solving hard optimization problems. Finally, the PI will work to integrate these passive error correction schemes with more traditional quantum error correction codes. In doing so, the PI will propose a new quantum computing architecture that could make it much easier to construct larger scale quantum computers.

Agency: NSF | Branch: Standard Grant | Program: | Phase: PROCESS & REACTION ENGINEERING | Award Amount: 500.00K | Year: 2016

Abstract - Albert - 1554555

Among the next generation of technologies are ones aimed at designing medical diagnostic devices that are more accurate and portable; electronic devices that are faster, smaller, and capable of storing more information; and energy sources that are cleaner without sacrificing capacity or power. Polymers with tunable nano- and micro-structured morphologies can address the challenges associated with accomplishing these goals, and solvent vapor annealing (SVA) is becoming an increasingly important technique for controlling polymer morphology. The goal of this proposal is to show that thermodynamic equilibrium principles can enable a priori selection of SVA conditions to guide experiments aimed at achieving a specific self-assembled morphology in a polymer system of interest.

The proposed thermodynamic framework and high-throughput experimental methods should facilitate rapid discovery of next generation polymer materials, improve the accessibility of designer polymers, and enable morphology control in polymer films to address technology challenges in the health, energy, and environment sectors. Thermodynamic equilibrium principles will be used to enable a priori selection of SVA conditions to guide experiments aimed at achieving a specific self-assembled morphology in a polymer system of interest. The PI plans studies aimed at predicting polymer phase behavior during SVA. She will apply thermodynamic principles to describe and predict the phase behavior of block copolymers in this process. These thermodynamic equilibrium principles are proposed to enable a priori selection of SVA conditions to guide experiments aimed at achieving specific self-assembled morphologies in polymer systems.

The aim of this project is to come up with an efficient manufacturing method for the production of tailor made polymer thin films, which could greatly benefit industry. Educationally, the proposed work should provide many opportunities for undergraduate students to carry out independent research projects and inspire some of them to pursue graduate studies. Activities carried out with the Society of Women Engineers (SWE) will contribute to increasing the representation of women in engineering undergraduate classes, doctoral programs, and leadership positions in industry, government, and academia. Specifically, undergraduate researchers enrolled for Independent Study have to develop research-related outreach workshops. The student-designed workshops will be integrated with existing outreach programs at Tulane such as the Girls in STEM at Tulane program, which targets 5th through 7th graders.

Agency: NSF | Branch: Standard Grant | Program: | Phase: Chem Struct,Dynmcs&Mechansms B | Award Amount: 439.90K | Year: 2016

In this collaborative project funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professors David N. Beratan and Peng Zhang of the Department of Chemistry at Duke University and Professors Igor V. Rubtsov and Russell H. Schmehl of the Department of Chemistry at Tulane University are developing novel ways to control the flow of electrical charge through molecules. Electron transfer at the molecular scale is essential in naturally occurring reactions and in devices of technological significance. The ability to dial in the rate of electronic motion and to control the directionality of these reactions on the molecular scale is a significant challenge that could open up new strategies for solar energy conversion, for understanding of biological energy conversion schemes, and for developing new strategies for devices of technological significance. The project includes intensive collaborations among chemical synthesis, ultrafast spectroscopy, and theory to establish a very rich interdisciplinary training environment for students. The team is promoting science and education by providing summer research opportunities to economically-disadvantaged and historically underrepresented groups. In addition, novel curriculum developments involve multi-university, multi-faculty teaching of courses that address the chemical and physical principles underpinning the research.

The overall aim of the project is to understand the chemical and physical approaches that use infrared perturbations to control charge flow at the molecular scale. The research also includes the design of novel molecular structures where the charge flow is strongly influenced by the infra-red radiation. The project combines the power of theoretical and experimental approaches to manipulate charge flow in molecules. The researchers use ultrafast multi-pulse spectroscopic methods in the laboratory to drive and to perturb the reaction dynamics of donor-bridge-acceptor compounds. Several classes of donor-bridge-acceptor molecular systems are prepared and studied, including transition-metal complexes, bimetallic complexes, hydrogen-bonded systems, and systems with bi-stable bridges. Using newly developed methods of non-equilibrium molecular dynamics, the same molecular systems examined in the experimental laboratory are simulated, targeting the development of understanding vibrational excitation that may perturb both reaction coordinate motion and donor-acceptor electronic coupling interactions.

Agency: NSF | Branch: Standard Grant | Program: | Phase: BIOTECH, BIOCHEM & BIOMASS ENG | Award Amount: 599.64K | Year: 2016

OConnor, Kim C.

Harnessing the regenerative capacity of mesenchymal stem cells (MSCs) has the potential to improve the quality of human life by repairing tissue damaged by disease, trauma and aging. A major challenge to realizing the therapeutic potential of these adult stem cells is their rapid depletion upon implantation at the site of tissue injury. MSCs exhibit significant cell-to-cell variation in their capacity to survive upon implantation, but the molecular basis for this heterogeneity is poorly understood. The objective of this project is to gain insight into the molecular mechanisms underlying the heterogeneity in MSC survival. This project helps to fulfill NSFs mission to advance the progress of science by generating fundamental knowledge about MSC survival at the molecular level. This knowledge has the potential to advance the stem cell field by developing novel methods to improve MSC survival. Greater MSC survival will overcome a critical barrier to achieve more effective MSC therapies. This study is broadly relevant to other types of stem cells inasmuch as all stem cells are inherently heterogeneous.

This project addresses a critical need to improve the survival of mesenchymal stem cells (MSCs) upon implantation. Rapid depletion of the majority of implanted MSCs impedes their ability to regenerate tissue upon engraftment. The PI has detected considerable cell-to-cell variation in MSC survival. The objective of this proposal is to gain insight into the molecular mechanisms underlying the heterogeneity in MSC survival. The central hypothesis is that MSCs are an ensemble of distinct cell subsets with different capacity to survive due to differential expression of key signaling molecules. This project is innovative in exploiting cellular heterogeneity to obtain unique insight into MSC survival on a molecular level. Aim 1 will evaluate a novel cell-surface marker of MSC survival in vivo, using a xenoimplantation assay to quantify survival kinetics. Aim 2 will employ bioinformatics to identify the first genome-wide gene signature of MSC survival, which will culminate in a binary classification model to predict MSC survival. This research is anticipated to develop novel molecular-based strategies to increase survival. Improving MSC survival is expected to have a positive impact on the therapeutic efficacy of engrafted MSCs. In addition, complementary educational activities will contribute to the training of a diverse STEM workforce, including students underrepresented in STEM fields. The project will provide interdisciplinary training for graduate and undergraduate students through a unique bioengineering curriculum and collaborative research, a hands-on laboratory experience with stem cells for middle school students, and other outreach activities. Project results will be broadly disseminated to students, scholars and the general public.
This award by the Biotechnology and Biochemical Engineering Program of CBET is co-funded by the Mathematical Biology Program of the Division of Mathematical Sciences.

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