Resume

• 2006

  University of Pennsylvania

  Texas A&M University

  Philadelphia

  •Proteomic analysis of nitration and chlorination of tyrosine on HDL particles.\n•Lipidomic analysis of phospholipid loss in HDL particles.\n•Demonstrated a correlation between lipid oxidative stress and protein misfolding.

  Senior Research Assistant

  University of Pennsylvania

• 2003

  University of Pennsylvania Health System

  St. George's University

  Grenada

  Philadelphia

  •Developed novel small molecule mass spectrometric assays to quantify lipid oxidative stress.\n•Used this technique to determine that Amyloid  protein functions as an oxidant and antioxidant.\n•Refined solubilization techniques for MALDI analysis of modified

  misfolded and insoluble proteins.\n•Novel biochemical/ mass spectrometric studies of the role of hydroxy-2-nonenal in protein misfolding.\n•Funded by private and NIH grants demonstrating effective research

  communication and writing skills.\n•Managed laboratory equipment and supply budgets.

  Research Associate

  University of Pennsylvania Health System

• 1999

  University of Pennsylvania

  •Identified structural regions of synuclein protein misfolding using circular dichroism and infrared spectroscopy.\n•Analyzed proteins using dialysis

  HPLC

  immunoprecipitation

  electrophoresis

  Western blots and ELISAS.\n•Conducted DNA analyses including cloning

  agarose gel electrophoresis

  and southern blots analysis.\n•Prepared

  grew

  harvested

  affinity purified and tested polyclonal and monoclonal antibodies.\n•Analyzed antibodies via biacore analysis and immunohistochemistry.

  University of Pennsylvania

  Assistant Professor

  •Identified amyloid plaques using a novel metal-based probe and a novel antibody method. Pioneered and published a unifying hypothesis for amyloid diseases

  including linking metabolic diseases and Alzheimer’s disease. Managed a $400K total budget and a team of up to 8.\n•Mechanistically linked metabolic dysfunction and amyloid protein misfolding in Alzheimer’s disease (Fawver

  Hall JAD 2012) and Type 2 Diabetes (manuscript in preparation). \n•Hypothesized that amyloids can function as sensors of dysfunction (Petrofes Chapa 2012).\n•Drug screening: screened anti- amyloid and antioxidant drugs for potential therapeutic use in Alzheimer’s disease (Fawver

  Duong JAD 2012).\n•Identified post-translational oxidation/glycation modifications of Amyloid β.(Murray 2007

  Ellis 2010)\n•Identified a novel metal based probe for imaging amyloid plaques in tissue sections and in vivo. (Cook 2012 in press)\n•Development of LCMS (QTRAP) methods to identify small compounds and lipids

  and MALDI TOF identification of posttranslational modification (including protelytic digests and sequencing).\n•Taught medical histology to medical students.\n•Implemented several changes in the histology course- including 5 self-study video modules and reformatting review sessions to Jeopardy game format. These changes

  studies over a 3 year period from 2010

  resulted in a significant increase in student exam scores.

  Texas A&M Health Science Center

  Russian

  Spanish

  English

  French

  Hillview

  Postdoctoral Training

  Neuroscience

  University of Pennsylvania School of Medicine

• 1994

  McGill University

  Merck

  McGill University

  Merck

  Montreal

  Canada Area

  •Pulmonary resistance & compliance screen for agents blocking arachidonic acid & leukotriene B pathways.

  Research Technician

  Taught physiology to medical students in the fall and spring (~1500/year with a very high student evaluation)\nDirector of Medical School Research Institute (MSRI) 2014-2019 (~50-100 students/year)\nProgram Director for Medical School Assessment Program (MSAP): an online admissions course.\n\nMy strengths also include:​\n•> 12 years in medical education\n• > 19 years of demonstrated research experience in neuroscience;\n• > 6 years research experience in diabetes and obesity;\n•Analytical

  innovative

  visionary

  and critical thinker; skilled at problem finding and problem solving;\n•Skilled in establishing research programs

  leading projects

  and laboratory management;\n•Effective early and rapid screening of existing drugs to avoid unnecessary lengthy clinical trials;\n•Have demonstrated both the ability to mentor and offer conflict resolution strategies;\n•Providing multiple opportunities to develop the strengths of junior researchers;\n•Developed a network of academic and biotech collaborations.\n\nTechnical Skills\n•Antibodies:Production

  purification

  conjugation. Antigenic epitope identification

  and mapping. immunization. Biacore

  ELISA

  and RIA. \n•Biochemistry: Lipid extraction and purification. Protein expression

  characterization

  and purification.\n•Biophysics: UV-Vis

  Fluorescence

  FTIR spectroscopy

  Circular dicroism.\n•Cell culture: Mammalian cells

  primary fibroblasts

  primary preadipocytes

  cell transformation

  hybridomas\nChromatography: FPLC

  HPLC

  ion exchange

  gel filtration

  reversed phase

  HPLC

  TLC\n•Gel electrophoresis: Western Blot

  Filter trap

  RIA

  ELISA

  IP

  and co-IP.\nMass spectrometry: GC/MS

  LCMS (LTQ

  QTrap 2000)

  MALDI (Voyager MALDI-TOF

  QSTAR

  4700 TOF/TOF).\n•Histochemistry: Colorimetric

  fluorescence.\n•Microscopy: Electron

  fluorescence

  light.\n•Transgenic models:  Transgenic animal models: Mouse

  C. elegans.​

  St. George's University

  Grenada

  Doctor of Philosophy (Ph.D.)

  •Initiated animal model studies to characterize Acylation Stimulating Proteins function.\n•Developed in-house methods to measure postprandial lipid and glucose metabolism in mice and cell culture.

  Obesity

  Diabetes

  McGill University

• 1993

  Pioneer Hi-Bred

  •Performed Agrobacterium mediated transformation and shoot regeneration of Canola.\n•Contracted for PCR RAPD (polymorphism) screening of tomato hybrid seed purity.\n•Developed a 96 well Mini-DNA extraction method for tomato leaf tissue samples.

  Research Technician

  Ontario

  Canada

  Pioneer Hi-Bred

  Houston

  Texas Area

  Associate Professor nontenure

  Texas A&M University

• 1988

  Bachelor of Science (B.Sc.)

  Biology/Biological Sciences

  General

  University of Waterloo

  Physiology

  Physiology

  Coursera

  Using Python to Access Web Data

  TYENCH2UAPAF

  Using Databases with Python

  3933WZ68S6RR

  Coursera

• Physiology

  Experimental Design

  Neuroscience

  Higher Education

  Online courses

  Teaching Classes

  Education

  Histology

  Human Physiology

  Train Employees

  Health Education

  Meta-analysis

  Cell Physiology

  Manage Complex Projects

  Cardiac physiology

  Teaching

  Muscle Physiology

  Systematic Reviews

  Cardiovascular Physiology

  Medical Education

  Ruthenium red colorimetric and birefringent staining of amyloid beta aggregates in vitro and in Tg2576 mice

  Alzheimer’s disease (AD) is a devastating neurodegenerative disease most notably characterized by the misfolding of amyloid-β (Aβ) into fibrils and its accumulation into plaques. In this Article

  we utilize the affinity of Aβ fibrils to bind metal cations and subsequently imprint their chirality to bound molecules to develop novel imaging compounds for staining Aβ aggregates. Here

  we investigate the cationic dye ruthenium red (ammoniated ruthenium oxychloride) that binds calcium-binding proteins

  as a labeling agent for Aβ deposits. Ruthenium red stained amyloid plaques red under light microscopy

  and exhibited birefringence under crossed polarizers when bound to Aβ plaques in brain tissue sections from the Tg2576 mouse model of AD. Staining of Aβ plaques was confirmed via staining of the same sections with the fluorescent amyloid binding dye Thioflavin S. In addition

  it was confirmed that divalent cations such as calcium displace ruthenium red

  consistent with a mechanism of binding by electrostatic interaction. We further characterized the interaction of ruthenium red with synthetic Aβ fibrils using independent biophysical techniques. Ruthenium red exhibited birefringence and induced circular dichroic bands at 540 nm upon binding to Aβ fibrils due to induced chirality. Thus

  the chirality and cation binding properties of Aβ aggregates could be capitalized for the development of novel amyloid labeling methods

  adding to the arsenal of AD imaging techniques and diagnostic tools.

  Ruthenium red colorimetric and birefringent staining of amyloid beta aggregates in vitro and in Tg2576 mice

  Neuronal and oligodendrocytic aggregates of fibrillar alpha-synuclein define several diseases of the nervous system. It is likely that these inclusions impair vital metabolic processes and compromise viability of affected cells. Here

  we report that a 12-amino acid stretch ((71)VTGVTAVAQKTV(82)) in the middle of the hydrophobic domain of human alpha-synuclein is necessary and sufficient for its fibrillization based on the following observations: 1) human beta-synuclein is highly homologous to alpha-synuclein but lacks these 12 residues

  and it does not assemble into filaments in vitro; 2) the rate of alpha-synuclein polymerization in vitro decreases after the introduction of a single charged amino acid within these 12 residues

  and a deletion within this region abrogates assembly; 3) this stretch of 12 amino acids appears to form the core of alpha-synuclein filaments

  because it is resistant to proteolytic digestion in alpha-synuclein filaments; and 4) synthetic peptides corresponding to this 12-amino acid stretch self-polymerize to form filaments

  and these peptides promote fibrillization of full-length human alpha-synuclein in vitro. Thus

  we have identified key sequence elements necessary for the assembly of human alpha-synuclein into filaments

  and these elements may be exploited as targets for the design of drugs that inhibit alpha-synuclein fibrillization and might arrest disease progression.

  A Hydrophobic stretch of 12 amino acid residues in the middle of alpha-synuclein is essential for filament assembly

  lycation is the reaction of a reducing sugar with proteins and lipids

  resulting in myriads of glycation products

  protein modifications

  cross-linking

  and oxidative stress. Glycation reactions are also elevated during metabolic dysfunction such as in Alzheimer's disease (AD) and Down's syndrome. These reactions increase the misfolding of the proteins such as tau and amyloid-β (Aβ)

  and colocalize with amyloid plaques in AD. Thus

  glycation links metabolic dysfunction and AD and may have a causal role in AD. We have characterized the reaction of Aβ with reactive metabolites that are elevated during metabolic dysfunction. One metabolite

  glyceraldehyde-3-phosphate

  is a normal product of glycolysis

  while the others are associated with pathology. Our data demonstrates that lipid oxidation products malondialdehyde

  hydroxynonenal

  and glycation metabolites (methylglyoxal

  glyceraldehyde

  and glyceraldehyde-3-phosphate) modify Aβ42 and increase misfolding. Using mass spectrometry

  modifications primarily occurred at the amino terminus. However

  the metabolite methylglyoxal modified Arg5 in the Aβ sequence. 4-Hydroxy-2-nonenal modifications were similar to our previous publication. To place such modifications into an in vivo context

  we stained AD brain tissue for endproducts of glycation

  or advanced glycation endproducts (AGE). Similar to previous findings

  AGE colocalized with amyloid plaques. In summary

  we demonstrate the glycation of Aβ and plaques by metabolic compounds. Thus

  glycation potentially links metabolic dysfunction and Aβ misfolding in AD

  and may contribute to the AD pathogenesis. This association can further be expanded to raise the tantalizing concept that such Aβ modification and misfolding can function as a sensor of metabolic dysfunction.

  Amyloid beta (β) metabolite sensing: biochemical linking of glycation modification and misfolding.

  http://www.ncbi.nlm.nih.gov/pubmed/22330832

  Amyloids as sensors and protectors (ASAP) hypothesis.

  Aggregated alpha-synuclein proteins form brain lesions that are hallmarks of neurodegenerative synucleinopathies

  and oxidative stress has been implicated in the pathogenesis of some of these disorders. Using antibodies to specific nitrated tyrosine residues in alpha-synuclein

  we demonstrate extensive and widespread accumulations of nitrated alpha-synuclein in the signature inclusions of Parkinson's disease

  dementia with Lewy bodies

  the Lewy body variant of Alzheimer's disease

  and multiple system atrophy brains. We also show that nitrated alpha-synuclein is present in the major filamentous building blocks of these inclusions

  as well as in the insoluble fractions of affected brain regions of synucleinopathies. The selective and specific nitration of alpha-synuclein in these disorders provides evidence to directly link oxidative and nitrative damage to the onset and progression of neurodegenerative synucleinopathies.

  Oxidative damage linked to neurodegeneration by selective alpha-synuclein nitration in synucleinopathy lesions

  Acylation stimulating protein (ASP) is a potent stimulator of triglyceride synthesis in adipocytes. In the present study

  we have examined the effect of an ASP functional knockout (ASP(-/-)) on lipid metabolism in male mice. In both young (14 weeks) and older (26 weeks) mice there were marked delays in postprandial triglyceride clearance (80% increase at 14 weeks and 120% increase at 26 weeks versus wild type (+/+)). Postprandial nonesterified fatty acids were also increased in ASP(-/-) mice versus ASP(+/+) mice by 37% (low fat 10% Kcal) and by 73% (high fat 40% Kcal) diets

  although there were no differences in fasting lipid levels. The ASP(-/-) mice had moderately increased energy intake (16% +/- 2% p < 0.0001) and reduced feed efficiency (33% increase in calories/g of body weight gained on low fat diet) versus wild type. The ASP(-/-) mice also had modest changes in insulin/glucose metabolism (30% to 40% decrease in insulin.glucose product)

  implying increased insulin sensitivity. As well

  there were decreases in leptin (29% shift in leptin to body weight ratio) and up to a 26% decrease in specific adipose tissue depots versus the wild type mice on both low fat and high fat diets. These results demonstrate that ASP plays an important role in adipose tissue metabolism and fat partitioning.

  Acylation stimulating protein (ASP) deficiency alters postprandial and adipose tissue metabolism in male mice

  Alzheimer's disease (AD) is a devastating neurodegenerative disease with pathological misfolding of amyloid-β protein (Aβ). The recent interest in Aβ misfolding intermediates necessitates development of novel detection methods and ability to trap these intermediates. We speculated that two regions of Aβ may allow for detection of specific Aβ species: the N-terminal and 22-35

  both likely important in oligomer interaction and formation. We determined via epitomics

  proteomic assays

  and electron microscopy that the Aβ42 species (wild type

  ΔE22

  and MetOx) predominantly formed fibrils

  oligomers

  or dimers

  respectively. The 2H4 antibody to the N-terminal of Aβ

  in the presence of 2% SDS

  primarily detected fibrils

  and an antibody to the 22-35 region detected low molecular weight Aβ species. Simulated molecular modeling provided insight into these SDS-induced structural changes. We next determined if these methods could be used to screen anti-Aβ drugs as well as identify compounds that trap Aβ in various conformations. Immunoblot assays determined that taurine

  homotaurine (Tramiprosate)

  myoinositol

  methylene blue

  and curcumin did not prevent Aβ aggregation. However

  calmidazolium chloride trapped Aβ at oligomers

  and berberine reduced oligomer formation. Finally

  pretreatment of AD brain tissues with SDS enhanced 2H4 antibody immunostaining of fibrillar Aβ. Thus we identified and characterized Aβs that adopt specific predominant conformations (modified Aβ or via interactions with compounds)

  developed a novel assay for aggregated Aβ

  and applied it to drug screening and immunohistochemistry. In summary

  our novel approach facilitates drug screening

  increases the probability of success of antibody therapeutics

  and improves antibody-based detection and identification of different conformations of Aβ.

  Probing and trapping a sensitive conformation: amyloid beta fibrils

  oligomers

  and dimers

  Alzheimer's disease (AD) is thought to start years or decades prior to clinical diagnosis. Overt pathology such as protein misfolding and plaque formation occur at later stages

  and factors other than amyloid misfolding contribute to the initiation of the disease. Vascular and metabolic dysfunctions are excellent candidates

  as they are well-known features of AD that precede pathology or clinical dementia. While the general notion that vascular and metabolic dysfunctions contribute to the etiology of AD is becoming accepted

  recent research suggests novel mechanisms by which these/such processes could possibly contribute to AD pathogenesis. Vascular dysfunction includes reduced cerebrovascular flow and cerebral amyloid angiopathy. Indeed

  there appears to be an interaction between amyloid β (Aβ) and vascular pathology

  where Aβ production and vascular pathology both contribute to and are affected by oxidative stress. One major player in the vascular pathology is NAD(P)H oxidase

  which generates vasoactive superoxide. Metabolic dysfunction has only recently regained popularity in relation to its potential role in AD. The role of metabolic dysfunction in AD is supported by the increased epidemiological risk of AD associated with several metabolic diseases such as diabetes

  dyslipidemia and hypertension

  in which there is elevated oxidative damage and insulin resistance. Metabolic dysfunction is further implicated in AD as pharmacological inhibition of metabolism exacerbates pathology

  and several metabolic enzymes of the glycolytic

  tricarboxylic acid cycle (TCA) and oxidative phosphorylation pathways are damaged in AD. Recent studies have highlighted the role of insulin resistance

  in contributing to AD. Thus

  vascular and metabolic dysfunctions are key components in the AD pathology throughout the course of disease. The common denominator between vascular and metabolic dysfunction emerging from this review appears to be oxidative stress and Aβ. ..

  Vascular and metabolic dysfunction in Alzheimer’s disease: A review.

  Ian

  Murray

  Texas A&M Health Science Center