Dr. Melissa A. Grunlan

Dr. Melissa A. Grunlan, assistant professor in the Department of Biomedical Engineering at Texas A&M University, will give a talk Wednesday (Nov. 25) at 3:30 p.m. in Room 203 of the Zachry Engineering Center on campus.

Grunlan’s talk, “Inorganic‐Organic Hybrid Polymeric Biomaterials,” is part of the biomedical engineering department’s seminar series.

Abstract
Development of the next‐generation of medical devices and therapies hinges on new biomaterials with superior properties. The rationale design of polymeric biomaterials involves establishing predictive relationships between polymer structure, material properties and performance in a particular application. Our research focuses on designing inorganic silicon‐containing polymers and their combination with organic polymers to obtain inorganic‐organic “hybrid” biomaterials. These hybrid materials achieve distinct properties that can be readily tailored based on the requirements of the application.

Our research has identified several applications in which hybrid biomaterials can enhance performance: clot‐resistant coatings, membranes for biosensors, tissue engineering scaffolds, and shape memory polymers. For blood‐contacting devices, surface‐induced thrombosis necessitates anti‐coagulant or anti‐platelet therapies. To minimize blood protein adhesion — the first event in surface‐induced thrombosis — we have prepared coatings with enhanced surface molecular mobility and with amphiphilicity by introduction of poly(ethylene glycol) (PEG) with flexible “siloxane tethers.” For implanted biosensors, biofouling of the membrane is considered to be a primary cause of failure. To extend biosensor lifetime, we have developed “self‐cleaning” thermoresponsive nanocomposite membranes comprised of polysiloxane nanoparticles embedded in a poly(N‐isopropylacrylamide) (PNIPAAm) matrix. Thermal modulation effectively removes adhered cells. In tissue engineering, a major hurdle to regenerating tissues that have the same properties (e.g. strength) of native tissues is the lack of understanding of how specific scaffold chemical and physical properties affect cell behavior and the regenerated tissue properties. To understand this, we have designed hydrogel scaffolds based on PEG and star‐polydimethylsiloxane (PDMSstar) with tunable chemical and physical properties including modulus, morphology, and hydration. Finally, shape memory polymers (SMPs) are of interest for a variety of interventional devices. We have prepared a new type of shape memory polymer comprised of polycaprolactone (PCL) and PDMS segments which give rise to unusually high deformability, rigidity, and shape memory properties that may be useful in these applications.

Submitted by Nicole Priolo, npriolo@bme.tamu.edu

Popularity: unranked [?]

Dr. Hai-Chao Han of the University of Texas at San Antonio’s Biomedical Engineering Program will give a talk Wednesday (Nov. 18) at 3:30 p.m. in Room 203 of the Zachry Engineering Center at Texas A&M University.

Han’s talk, “The Theory and Application of Artery Buckling,” is part of the Department of Biomedical Engineering’s seminar series.

Abstract
The mechanical stability of blood vessel is important for maintaining normal blood flow and vascular function. While it is well known that blood vessels collapse under external pressure, blood vessels are commonly considered to be stable under internal pressure. Our recent studies showed that increased lumen pressure and reduced axial tension can lead to instability in blood vessels. The theoretical models and experimental results will be presented in this talk. A possible application in the study of vessel tortuosity will be discussed. We propose that mechanical buckling could be a possible mechanism in the development of tortuous blood vessels that are often observed in many patients.

Submitted by Nicole A. Priolo, npriolo@bme.tamu.edu

Popularity: unranked [?]

Dr. Ana Egatz-Gomez, a TEES research assistant professor in biomedical engineering at Texas A&M University, will present a lecture Wednesday (Nov. 11) at 3:30 p.m. in Room 203 of the Zachry Engineering Center on campus.

Her talk, “Digital Magnetofluidics and Molecular Separations in a Drop,” is part of the Department of Biomedical Engineering’s seminar series.

Abstract
Digital magnetofluidics consists of a novel drop manipulation microfluidic technique. It relies on magnetic fields to control the movement of drops in air, on silicon nanowire (Si NW) superhydrophobic surfaces, using magnetizable micro‐ or nano‐ particles. Key operations such as movement, coalescence, and splitting of aqueous and biological fluid drops, as well as electrochemical measurement of dopamine and glucose have been demonstrated. It is possible to create pH gradients in a drop for protein electrophoresis and isoelectric focusing. Fractions with different pI ranges can be obtained through drop splitting. Digital magnetofluidics‐based protein separations can be performed with extreme ease and simplicity, working with proteins in either native or denaturized state, in a few minutes and using low voltage, and also holds promise as a method for removing albumin from serum samples for blood analyses. This is a technology with great potential as a means for rapid preparation and analysis of microliter‐sized biological fluid samples.

Submitted by Nicole Priolo, npriolo@bme.tamu.edu

Popularity: unranked [?]

From left: Rodrigo Garza Urquiza, Rachel Oyler, David Gent, Alexandra Iacob, Colin Bailie, Mark Deimund.

The Dwight Look College of Engineering at Texas A&M University honored five students with its Craig C. Brown Outstanding Senior Engineer Award during a banquet at Miramont Country Club in Bryan.

Seniors Colin Bailie, Mark Deimund, Alexandra (Sandra) Iacob, Rachel Oyler and Rodrigo Garza Urquiza received the annual award due to their academic achievement, character and leadership abilities.

Dr. G. Kemble Bennett, vice chancellor and dean of engineering, presented the awards to the students.

Colin Bailie is a mechanical engineering major from Plano. He is described as a disciplined, dedicated and well-spoken student, both inside the classroom and out.

He is a member of several on-campus groups, and has held leadership roles with the Singing Cadets and the a capella singing group Apotheosis. He has given back to the community through Habitat for Humanity, Replant and Relay for Life.

Bailie is involved with the American Society of Mechanical Engineers and the American Nuclear Society. He has been inducted into the Pi Tau Sigma and Tau Beta Pi honor societies.

During summer 2008 Bailie was a test intern for Enfora in Dallas where he helped move the company toward automation. This past summer he was one of 15 research interns at the Lawrence Livermore National Laboratory in California, and will submit a journal article based on his findings. Currently he conducts research with a Texas A&M professor to build a shock tube for better understanding of multiphase shock accelerated flow physics. Bailie will graduate in May 2010.

Mark Deimund is a chemical engineering major from Oklahoma City, Okla. Cited by one professor as among his top 10 undergraduates in the last quarter-century. Deimund is a member of four honor societies: Tau Beta Pi, Omega Chi Epsilon, Phi Kappa Phi and Phi Eta Sigma. His current term as president caps three years of leadership roles in the Texas A&M chapter of the American Institute of Chemical Engineers.

He has been a Chem-E Car team leader since 2007, guiding his group to multiple wins at regional and national competitions. He has worked summers for Celanese Chemicals as an R&D intern in Texas and a process engineering intern in Virginia. His volunteer work has included Texas A&M Big Event, Habitat for Humanity and Super Summer Southern Baptist Youth Leadership Camp.

Deimund has assisted with Texas A&M research on a biomass processing technique that is being patented and published. He visited 15 states during travels this past summer and still managed to earn his Business Management Certificate for Engineers. He will graduate in May 2010.

Alexandra (Sandra) Iacob is a biomedical engineering major from Bucharest, Romania. A University Research Scholar, Iacob is a three-year leader in the Society of Women Engineers, currently serving as internal vice president. She also has served as president of the Romanian Club.

During summer 2009 Iacob participated in Texas A&M’s Undergraduate Summer Research Grant program, after concluding two years as an undergraduate research assistant in the chemical engineering department. She interned at the Pittsburgh Tissue Engineering Institute at Brooke Army Medical Center and spent one semester as a student researcher with the Michael E. DeBakey Institute at Texas A&M. She gives back to the community as a hospital volunteer helping in the pre-op room.

Fluent in four languages and knowledgeable of two more, Iacob is recognized for her compassion, leadership and dedication to making the world better for others. She will graduate in December 2009 with the distinction of having completed the Engineering Scholars Program.

Rachel Oyler is an electrical engineering major from Sundown, Texas. She is a member of the Tau Beta Pi, Eta Kappa Nu and Phi Eta Sigma honor societies, and the Society of Women Engineers.

Oyler has been a leader in her sorority, Gamma Phi Beta, earning two of its highest awards for exemplifying the core values of love and learning. Since 2005 she has continued to volunteer at a local camp for handicapped, disabled and terminally ill children. Her summers at Texas A&M have been well spent, including a summer internship with The Boeing Company’s International Space Station electrical power system group, Study Abroad in Italy and a summer internship with the IT Design Systems group at Texas Instruments.

She is repeatedly described as exceptionally intelligent and an outstanding leader and role model with a superb work ethic and enviable time management skills—a person who exemplifies the honor and tradition of Texas A&M. Oyler will graduate in December 2009.

Rodrigo Garza Urquiza is a mechanical engineering major from Corregidora, Queretaro, Mexico. He is president of the American Society of Mechanical Engineers student section. ASME and Tau Beta Pi national engineering honor society nominated him for the Leadership Exchange Program in Qatar, where he spent spring break 2009.

He has enjoyed three internships: systems engineering for Compressor Controls Corporation; mechanical research, Chicago Bridge and Iron; and sand control technology, Halliburton. He currently serves as a research assistant in the Texas A&M Turbomachinery Laboratory. Professors have described him as a very rare student and the best all-around undergraduate in mechanical engineering at Texas A&M, crediting him with the talent and drive to succeed in any professional situation.

He said prides himself on staying active outside of the classroom as well as with extracurricular activities such as the Texas A&M Golf Club, tennis intramurals, triathlon training and giving back to the community through Big Event and Aggie Replant. He will graduate in May 2010.

Each of the seniors received an engraved medallion and a $5,000 educational grant. Their names appear on a plaque in the Zachry Engineering Center.

The Engineering Faculty Senior Award was renamed the Craig C. Brown Outstanding Senior Engineer Award in 1996 in recognition of Brown’s endowment for the award. He received the award as a Class of 1975 civil engineering senior. Currently, Brown is chief operating officer, owner and president of Bray International Inc. as well as chairman and president of the Craig and Galen Brown Foundation.

David W. Gent, Class of ’75, senior vice president of Bray International, represented Brown, who was sick with the flu. Gent also received the award as a senior electrical engineering major.

Popularity: unranked [?]

The Department of Biomedical Engineering at Texas A&M University will host a seminar on measuring deformation Wednesday (Nov. 4) at 3:30 p.m. in Room 203 of the Zachry Engineering Center on campus.

Dr. Katia Genovese, faculty member in the Department of Environmental Engineering and Physics at the University of Basilicata (Italy), will present the seminar, “Deformation Measurement With the Digital Image Correlation Method,” as part of the biomedical engineering department’s seminar series.

Abstract
The talk will present an experimental approach that uses a digital image correlation technique to provide deformation and strain measurements in a form of two-dimensional contour maps for planar surface specimens. Relationships between some of the most important variables involved in the digital image correlation process will be discussed together with strength points and limitations of the technique. The talk will include a simple tutorial for processing data obtained from a biaxial-test on a cruciform specimen.

Submitted by Nicole Priolo, npriolo@bme.tamu.edu

Popularity: unranked [?]

The Department of Biomedical Engineering at Texas A&M University will host the Department of Biology’s Dr. Mark Harlow for a lecture on neurotransmitters Wednesday (Oct. 28) at 3:30 p.m. in Room 203 of the Zachry Engineering Center on campus.

Harlow’s talk, “The Structural Organization of Macromolecules Responsible for Neurotransmitter Secretion During
Synaptic Transmission,” is part of the biomedical engineering department’s seminar series.

Abstract
Research in the Harlow laboratory focuses on the structural organization of macromolecules responsible for neurotransmitter secretion during synaptic transmission. Synaptic transmission regulates virtually all aspects of animal behavior; consequently, there is considerable interest in the underlying mechanisms. My previous research concerned dense aggregates of macromolecules that play an important role in synaptic transmission at chemical synapses, and the relationship of these aggregates to synaptic vesicles (SV). These aggregates, referred to as active zone material (AZM), stud the cytoplasmic surface of the plasma membrane in the presynaptic neuron just opposite the postsynaptic cell, and are situated next to releasable SVs docked on the presynaptic membrane and calcium channels concentrated within the membrane. Because the components of AZM are composed of macromolecules, they can only be visualized in situ using the electron microscope. I employed a technique called electron tomography (ET) to study the 3D structure of AZM at the highest resolution possible.

Although AZM was first detected more than 50 years ago, its structure and function have not been elucidated. Hypotheses as to the role AZM plays in synaptic transmission have included: a site of adhesion for pre- and post‐synaptic cells; a synaptic vesicle adhesion site; and a macromolecular complex directly involved in vesicle fusion. As a step toward making direct tests of these hypotheses, I characterized the structure of a subset of the AZM and its relationship to docked vesicles and the adjacent region of the presynaptic membrane that contains calcium channels. Specifically, I used ET to generate 3D reconstructions of tissue sections to determine the structure of specific components of the AZM and their spatial relationships at the frog’s neuromuscular junction, a model synapse. My results provide compelling evidence that the active zone material at the frog’s neuromuscular junction helps dock SVs and anchor calcium channels and that the architecture of the material provides for both a
particular spatial relationship and a structural linkage between the vesicles and the channels.

My current research project involves the study of SVs and their relationship to the AZM. In samples prepared under classic conditions, the lumens of SVs appear empty. However, numerous filaments can be seen in vesicles prepared by rapid freezing and cryo‐staining, with the filaments occupying approximately 10 percent of the lumen’s volume. These filaments, many of which are likely luminal domains of SV proteins, may help tether synaptic vesicle proteins together during vesicle recycling, and could play a role in vesicle protein organization. Indeed, the arrangement of filaments inside each vesicle appears to be constant from vesicle to vesicle, with differing orientations for docked and undocked vesicles. This raises the possibility that, much like the AZM, each vesicle contains a highly organized arrangement of proteins. In order for synaptic transmission to occur, these luminal structures may need to be in a specific orientation so that vesicle proteins can precisely align with the AZM.

Popularity: unranked [?]

Dr. Wayne Orr, assistant professor of pathology at the Louisiana State University Health Sciences Center, will give a talk Wednesday (Oct. 21) at 3:30 p.m. in Room 203 of the Zachry Engineering Center at Texas A&M University.

Orr’s talk, “CenterMatrix-specific signaling in shear stress-induced endothelial cell dysfunction,” is part of the Department of Biomedical Engineering’s seminar series.

Abstract
Endothelial cell dysfunction initiates early atherosclerotic plaque formation by promoting local LDL accumulation and facilitating leukocyte recruitment, whereas endothelial cell dysfunction in advanced plaques may contribute to thrombotic complications through enhanced endothelial cell turnover and leukocyte-dependent degradation of the plaque’s fibrotic cap. Regulation of endothelial cell dysfunction is multifactorial; classically ascribed to the combined effects of blood flow patterns and systemic risk factors. My research suggests that subendothelial matrix
composition is a novel regulator of endothelial cell dysfunction.

Shear stress, the frictional force generated by blood flow, activates the integrin family of extracellular matrix receptors resulting in enhanced receptor affinity, and matrix-specific integrin signaling alters the endothelial cell response to flow. Transitional matrix proteins, such as fibronectin and fibrinogen, accumulate in the subendothelial matrix early during endothelial cell dysfunction in vivo and prime endothelial cells for dysfunction in vitro by enhancing flow-induced permeability, proinflammatory signaling (NF-κB, JNK), and inflammatory gene expression. In contrast, basement membrane proteins are protective and limit flow-induced endothelial cell dysfunction. In this presentation, we will explore the mechanisms of the matrix-specific response to shear stress and examine the roles of p21 activated kinase (PAK) and protein kinase A (PKA) signaling in mediating this matrix-specific response.

Popularity: unranked [?]

The Department of Electrical and Computer Engineering at Texas A&M University sponsored the university’s inaugural Nano/Micro Poster Symposium to promote multidisciplinary interaction and scientific communication among students and faculty in the field of nano/micro technology.

The Department of Electrical and Computer Engineering sponsored the inaugural Nano/Micro Poster Symposium.

The symposium started with an invited talk, “Three Dimensions of Individualized Nanomedicine,” from Dr. Mauro Ferrari, a world-renowned expert in nanomedicine. He is currently a professor and chairman of the Department of Nanomedicine and Biomedical Engineering and a professor of internal medicine, at the University of Texas Health Science Center in Houston, as well as a professor of bioengineering at Rice University and president of the Alliance for NanoHealth in Houston. This also was the inaugural talk for the newly launched monthly Texas A&M Nano/Micro Seminar Series.

Following Ferrari’s talk was a poster session, which included more than 65 posters from various disciplines, with more than 150 people from 16 departments across campus participating.

The steering committee was lead by Dr. Arum Han, assistant professor in the electrical and computer engineering department. Other committee members included: Dr. Arul Jayaraman, chemical engineering; Dr. Mike McShane, biomedical engineering; Dr. Dong Hee Son, chemistry; Dr. Winfried Teizer, physics; and Dr. Choongho Yu, mechanical engineering.

Written by Deana Totzke, deana@ece.tamu.edu

Popularity: unranked [?]

Dr. Junghae Suh, assistant professor in the Department of Bioengineering at Rice University, will present her gene delivery research Wednesday (Sept. 30) at 3:30 p.m. in Room 203 of the Zachry Engineering Center at Texas A&M University.

Suh’s talk, “Reprogramming Viruses for Controlled Gene Delivery,” is part of the Department of Biomedical Engineering’s seminar series.

Abstract
Delivering nucleic acid-based therapeutics into target cells specifically is a considerable challenge. Using concepts and tools from virology, protein engineering, and molecular biology, we are interested in developing virus-based gene delivery vectors to tackle this challenge in an innovative way. In the first application, we are focused on utilizing virus-based gene delivery vectors for tissue engineering/regenerative medicine.

A significant hurdle in tissue engineering and regenerative medicine is the difficulty in achieving spatially organized tissue structures. To drive the proper hierarchical differentiation and assembly of cells, gene expression patterns may need to be tightly regulated. This may entail the expression of certain genes, involved in tissue genesis or repair, to be upregulated or downregulated in a spatially dependent manner. We are working towards leveraging the unique advantages of virus-based gene delivery systems to achieve this goal.

In a second application, we are building a toolkit of innovative virus nanoparticles that can deliver nucleic acids specifically into breast cancer cells. In particular, we are using advances in protein engineering to develop viruses that are activated by tumor-specific biomolecular inputs.

Overall, such sophisticated gene delivery vectors should yield improvements in the control and efficiency of nucleic acid delivery and lead to enhanced therapeutic outcomes.

Biography
Dr. Junghae Suh received her B.S. in chemical engineering from the Massachusetts Institute of Technology and Ph.D. in biomedical engineering at Johns Hopkins University’s School of Medicine. Before joining the Rice University Department of Bioengineering in 2007, she completed a two-year postdoctoral fellowship in the Laboratory of Genetics at the Salk Institute for Biological Studies. Her graduate research focused on understanding the interaction of nanoscale systems, either nature-derived or human-engineered, with complex biological environments in an effort to discover ruling paradigms that govern the performance of nanoparticles designed for various diagnostic and/or therapeutic applications. Her postdoctoral research focused on studying how natural viruses interface with cellular machinery, particularly those that maintain homeostasis in the cell nucleus. Such studies should uncover new insights into how synthetic nanoparticle systems can be designed to yield the performance efficiencies rivaling that of viruses.

Currently, Suh works at the interface of chemistry, virology, biophysics, molecular biology and protein engineering to investigate and create novel virus-based materials for various biomedical applications. She has recently been awarded the U.S. Department of Defense Breast Cancer Concept Award and the Hamill Innovation Award for her innovative work on reprogramming viruses as therapeutic platforms.

For more information regarding this seminar, please contact Dr. Arum Han at arum.han@ece.tamu.edu.

Popularity: unranked [?]

Dr. Harry A. Hogan, an associate professor in the Department of Mechanical Engineering at Texas A&M University, will give a talk on his musculoskeletal research Wednesday (Sept. 23) at 3:30 p.m. in Room 203 of the Zachry Engineering Center on campus.

Dr. Harry A. Hogan

Hogan’s talk, “Musculoskeletal Response to Simulated Microgravity and Exercise in an Adult Rat Animal Model,” is part of the Department of Biomedical Engineering’s seminar series.

Abstract
The adult hindlimb unloaded (HU) rat has gained wide acceptance and usage as a ground-based analog model for studying musculoskeletal effects of microgravity. This model is employed extensively in a wide range of investigations aimed at better understanding of the effects of long-term space flight on the musculoskeletal system. Obvious advantages of the animal model include the ability to tightly control experimental variables, to include destructive tissue assays, and to complete tests in a relatively short period of time, particularly compared to long duration astronaut missions. Current countermeasure strategies employed on the International Space Station (ISS) have not yet proven to be sufficiently effective, so important questions remain. We have conducted a series of studies in recent years using the rat HU model to seek greater insight into the various contributing factors. More specifically, we have used a muscle stimulation protocol that simulates resistive exercise as a countermeasure during HU and quantified the response of both muscle and bone. Primary muscle outcomes include muscle mass and strength.

Bone outcomes have been derived from peripheral Quantitative Computed Tomography (pQCT) scans as well as direct mechanical testing. Several pQCT variables show bone loss and recovery patterns that match analogous astronaut data impressively well. Results also show a dramatic mismatch in the recovery rates of muscle and bone; muscle recovers strength much more rapidly than bone. A series of studies have been conducted varying the details of the muscle stimulation protocol, and the consistent finding has been a very potent anabolic effect on bone but only modest effects on muscle. In order to gain better insight into possible reasons for the responses observed, companion studies were also conducted in which strain gages were implanted on the bone surfaces in order to quantify the strain characteristics experienced by the bone during the exercise protocols. The seminar will also include descriptions of some of the challenges unique to mechanical testing of specimens from the rat. In addition, an overview will be provided on related new projects and future directions.

Popularity: unranked [?]