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Poster Presentations

M.S. Student Poster Presentations

MPP01

Silver Coated Carbon Nanotubes for Inhibition of Salmonella in Two vs Three Dimensional Hep-2 Cell Model

Brandi Barlow1, Atul Chaudhari1, Kunal Kate2, Sundar Atre2, Shree Singh1, and Shreekumar Pillai1,*

1Center for Nanobiotechnology Research, Alabama State University, Montgomery, Alabama 36104; 2Department of Mechanical Engineering, University of Louisville, Louisville, Kentucky 40292. *Email: spillai@alasu.edu

Salmonellosis, caused by Salmonella serovars, is a food borne illness caused by consumption of contaminated food and water. Among the serovars, Salmonella enterica serovar Typhimurium causes food poisoning worldwide, with millions of cases and steadily increasing mortality rates. Therefore, potential therapeutic agents to control or effectively treat such Salmonella infections are needed. In these efforts nanotechnology has emerged as an effective tool as metallic nanoparticles exhibit antibacterial potential. In particular, silver coated carbon nanotubes (AgCNTs) are well known to have antibacterial activity against several Gram-positive and Gram-negative bacteria. In this study, Hep-2 cells (105 cells) were seeded 2D and infected with a 1:1 ratio of bacteria to cells for 3 h. In 2D models the 1:1 MOI ratio showed a 3 log fold increase in bacterial counts. In order to develop 3D models of infection, HEp-2 cells were grown on 3D printed, scaffolds designed at the University of Louisville. We will use the MOI of 1:1 with the 3D cellular model of HEp-2 cells to further investigate the antibacterial effect of silver coated carbon nanotubes against Salmonella Typhimurium infection. The long term goal of this project is to define the antibacterial mechanism of action for these nanoparticles comparing 2D vs. 3D cellular models.

Douce GR, IAmin II, and Stephen J. Invasion of HEp-2 cells by strains of Salmonella typhimurium of different virulence in relation to Gastroenteritis

Chaudhari AA, Jasper SL, Dosunmu E, Miller ME, Arnold RD, Singh SR, and Pillal S. Novel PEGylated silver coated carbon nanotubes kill Salmonella but they are non-toxic to eukaryotic cells.

Robert Y. Pelgrifta, Adam J. Friedman- Nanotechnology as a therapeutic tool to combat microbial resistance

MPP02

Gait Analysis of Transfemoral Amputees: A Comparison of Osseointegration and Socket Suspension

Caitlyn Yantz and Adetoun Komolafe*

Department of Prosthetics and Orthotics, Alabama State University, Montgomery, Alabama 36104. *Email: tounkomo@gmail.com

Osseointegration (OI) is the direct contact between living bone and the surface of synthetic implant (Leijendekkers et al., 2016). Osseointegration can potentially provide greater stability and control, as well as minimize energy exertion, while providing a perfect fit via a torque controlled knee connector. The functional outcome of transfemoral amputees can be assessed using a range of spatial and temporal gait characteristics, as well as kinematic and kinetic measures (Frossard et al., 2010). This study was designed to analyze how kinetic forces in the gait cycle of amputees with osseointegration (OI) compares to those with traditional socket suspension. The participants included two transfemoral amputees, one with an OI fixation and the other with a traditional socket. Additionally, data was collected for an able-bodied individual for comparison with normal gait. Data was collected using the Gait Real-time Analysis and Interactive Laboratory (GRAIL) system with participants using their current prosthetic componentry. Data was collected for five trials walking on a normal level, uphill conditions, and downhill conditions. The osseointegration participant had significantly smaller values (p < 0.05) for vertical ground reaction forces and hip angles, with comparable or significantly higher hip moments and power. The results indicate that the fixation enables the OI participant to walk with a comparable gait pattern to the socket participant, as well as have a comparable hip power. This study provides information that can be utilized by clinicians challenged with restoring a “normal” gait pattern for lower limb amputees with osseointegration.

 Frossard L, Hagberg K, Haggstrom E, Gow D, Branemark R, and Pearcy M (2010). Functional outcome of transfemoral amputees fitted with an osseointegrated fixation: Temporal gait characteristics. J. Prosthetics Orthotics, 22(1), 11-20.

Leijendekkers RA, Hinte GV, Frölke JP, Meent HV, Sanden MW, and Staal JB (2016). Comparison of bone-anchored prostheses and socket prostheses for patients with a lower extremity amputation: a systematic review. Disability and Rehabilitation, 39(11), 1045-1058. doi:10.1080/09638288.2016.1186752

Osseointegration Group of Australia (2017). Background of Osseointegration. Retrieved August 14, 2017, from http://www.osseointegrationaustralia.com.au/background-ofosseointegration

Van de Meent H, Hopman M, and Frolke J (2013).  Walking ability and quality of life in subjects with transfemoral amputation: A comparison of osseointegration with socket prostheses. Arch. Phys. Med. Rehabilitation, 94, 2174-8.

MPP03

Synthesis of Biomaterial using Polycaprolactone and Polydioxanone Nanofiber Scaffolds Used for Skin Tissue Engineering

Kendra Swain1, Vinoy Thomas2, and Komal Vig1,*

_Center of NanoBiotechnology Research, Alabama State University, Montgomery, Alabama 36104; _Department of Materials Science and Engineering, University of Alabama at Birmingham, Birmingham, Alabama 35294. *Email: komalvig@alasu.edu

Over the past few years’ tissue engineering and regenerative applications have yielded many neoteric tissue replacements and implementations. Electrospinning is a valuable technique for the fabrication of 3D fiber scaffolds for advanced wound healing and in this manner reclamation of the skin. Scaffolds are comprised of biocompatible biomaterials, such as collagen, manufactured materials, or in the current study a combination of polycaprolactone (PCL), and polydioxanone (PDO). PCL is a long-degrading polymer and is FDA approved with high porosity and PDO which has been used for biomedical applications, mostly in the form of surgical sutures. These polymers were fabricated into a bioresorbable scaffolds through electrospinning. This newly designed functionally graded composition will be used for skin growth. Scaffolds were synthesized using PDO and PCL which were dissolved in hexaflouro -2- propanol (HFIP) and stirred 24h. Different polymer solutions of PDO, PCL, PDO+PCL, and PDO+PCL+ Collagen were used for making the scaffolds used.  Electrospinning parameters were optimized to get fibers evenly dispersed across metal spiked plate. Scaffolds were then vacuumed dried for 2 days before characterization. Morphology and fiber composition were analyzed with Scanning electron microscopy (SEM). Tensile properties were measured with a dynamic mechanical analyzer (DMA). Scaffolds were sterilized by UV light and afterwards washing with ethanol, sterile distilled water, and finally HBSS. The growth and proliferation of normal human keratinocytes were evaluated in keratinocyte growth serum and our EpiLife medium. Fibroblast was grown in DMEM 10 media until confluent.  Scaffolds were then placed into a 48 well plate and seeded with keratinocytes and fibroblast in separate wells for 21 days. Synthesized scaffolds showed cell growth on scaffolds were 100% viable on days 3 and 5 with a decrease to 90% on days 7 and down to 80% on day 15. Keratinocytes and Fibroblast were viable on all variable scaffolds used. In conclusion scaffolds were successfully spun for PDO and PCL synthesized polymers. SEM showed ECM mimicking fibrous morphology for each blend that was used. Cell studies confirms cell adhesion and growth on scaffolds used for extended periods. Future studies are to develop procedures for establishing confluent, layers of co-cultured human keratinocytes and fibroblast on the surface of synthesized PDO and PCL scaffolds.

MPP04

The Inhibition of Staphylococcus aureus Infection by Silver Coated Carbon Nanotubes Using 3D Cell Culture and Keratinocytes

Talia Harper, Brandi Barlow, Atul A Chaudhari, Shree Ram Singh, and Shreekumar Pillai*

Center for Nanobiotechnology Research, Department of Biological Sciences, Alabama State University, Montgomery, Alabama 36104. *Email: spillai@alasu.edu

Staphylococcus aureus is a Gram-positive bacterium that causes a range of illnesses including serious skin infections. These infections range from life threatening diseases like toxic shock syndrome to mild acne. Staphylococcus aureus can infect over 100,000 patients in a hospital every year and is known as one of the most common nosocomial infections. A rising worldwide problem in modern day medicine is antibiotic- resistance. Therefore, it is of utmost concern to develop anti-Staphylococcus remedies to treat the skin infections. The use of metallic nanoparticles is becoming important in developing innovative antibacterial methods. In recent years, 3 dimensional (3D) cell cultures have become popular in investigating cell infection and evaluating the antibacterial potential of several different antibacterial agents. In this experiment, we developed a 3-D model of human keratinocytes based on Alvetex scaffold (Reinnervate Inc) and investigated the multiplicity of infection (MOI) for Staphylococcus aureus. For this study, the keratinocyte cells (105 cells) were seeded on Alvetex scaffolds and the cells were infected with the ratios of bacteria to cells as 1:1; 10:1; and 100:1 for 3 h. To determine the MOIs at 3h post infection, the cells were lysed using Triton-X100 and the appropriate dilutions were plated on Luria Burtani (LB) agar plates. The plate counting method was used to determine the MOI for each ratio. The results showed that the bacteria to cells ratios 1:1, 10:1 and 100:1 yielded 1 x 108 , 2.2 x 108  and 6.3 x 108 colony forming units, respectively. Our results suggested that the 10:1 ratio showed 3 log fold increase in bacterial counts compared to the other two ratios. Based on our experiments, our MOI for Staphylococcus aureus is 10 bacteria to 1 cell to establish the infection. We intend to use this MOI with the 3D cellular model of keratinocytes to further investigate the antibacterial effect of silver coated carbon nanotubes against Staphylococcus aureus infection. The long term goal of this project is to define the antibacterial mechanism of action for these nanoparticles using 3D cellular models.

Brown, Aisling F. et al (2013) “Staphylococcus Aureus Colonization: Modulation of Host Immune Response and Impact on Human Vaccine Design.” Frontiers in Immunology 4, 507.

Soong G, Paulino F, Wachtel S, Parker D, Wickersham M, Zhang D, Brown A, Lauren C, Dowd M, West E, Horst B, Planet P, and Prince A (2015) “Methicillin-resistant Staphylococcus aureusadaptation to human keratinocytes.” PMC MBio. 2015; 6, e00289-15. doi: 10.1128/mBio.00289-15.

MPP05

Measurement Accuracy: A Comparison Between Healthcare Professionals

Meghan Voss, Michele Hester, and Adetoun Komolafe*

Department of Prosthetics and Orthotics, Alabama State University, Montgomery, Alabama 36104. *Email: Tounkomo@gmail.com

Patient limbs, residual and intact, have daily volume fluctuations that occur for a myriad of reason, which is why measurement of affected limbs before and after treatment is essential to maintain the effectiveness of the prosthesis or orthosis (Tan, Coutts, Bulley, 2013). One common and standard way to concretely determine volume change is through anthropomorphic measurements (Susato, 2011). Healthcare professionals all receive a different education in respect to measurement techniques; in addition to this, their measurement skills are used in varying amounts in daily practice. This study compared the accuracy and reliability of several anthropometric measurements taken by groups of physical therapy (PT) students, occupational therapy (OT) students, prosthetic and orthotic (PO) students, and PO professionals. The purpose of this study was to determine which group of health care professionals took the most accurate anthropometric measurements. The study consisted of four second year PT students, four second year OT students, five second year PO students, three certified POs, one certified Orthotists, and one certified PO assistant. Participants were timed while they measured a foam model at marked points. All measurements were averaged and compared to the scanner measurements and percent errors with P-values were calculated. It was determined that the group with the lowest percent error was the PT group. The fastest group was the PO student group. The group with the lowest number of measurements sites with significant error based on P-values was also the PT group.

Tan C, Coutts F, and Bulley C (2013). Measurement of lower limb volume: Agreement between the vertically oriented perometer and a tape measure method. Physiotherapy, 99(3), 247-251. doi:10.1016/j.physio.2012.12.004

Susato S (2011) Development and Application of Portable Manual Non-Contact-Type Anthropometric Instruments for Measuring Human Anatomical Longitudinal Parameters. J. Physiological Anthropology,30(2), 55-67. doi:10.2114/jpa2.30.55

MPP06

Synthesis and Characterization of a Tri-Phase Hydrogel Scaffold for Cartilage Restoration

Tambre A.Tolliver1, Derrick Dean1,*, and Mohamed Abdalla2

1Biomedical Engineering Program, Alabama State University, Montgomery, Alabama 36104; 2Department of Chemistry, Tuskegee University, Tuskegee, Alabama 36088. *Email: ddean@alasu.edu

There is an estimated 27 million Americans that suffer from osteoarthritis in the age range of 25 and older. Osteoarthritis causes the degeneration of joint cartilage that cannot be restored by the body. Therefore there is a need for 3D scaffolds for the regeneration of a synthetic cartilage. We have investigated the synthesis and characterization of a tri-phase hydrogel scaffold for cartilage restoration. The overall goal of our work is to study the processing-property-function relationships to formulate bioink for 3D printing of these hydrogels. Research has been conducted that shows hydrogels can possibly be used to replace cartilage. Polyvinyl alcohol and Sodium alginate are polymers commonly studied for their similarities to cartilage. Bioinks are formed to duplicate the extracellular matrix to aid in the adhesion, proliferation, and differentiation of cells. The hydrogel system is based on polyvinyl alcohol, sodium alginate and hydroxyapatite. The scaffold was subjected to the process of freeze-thawing, and cross linking to form a synthetic articular cartilage. The modulus of the solutions was found to increase with increasing amounts of SA and degree of crosslinking. FTIR confirms the presence of SA at 1550, HA at 1040, O-H at 3610, and C-H at 2950. Rheology was used to measure the viscosity to select a sample that fits the target range for 3D printing. Morphology of the scaffolds was characterized with scanning electron microscopy. We successfully created three tri-phase hydrogel scaffolds that varied in porosity, sodium alginate concentration, and viscosity. SA concentration affects the mechanical properties and porosity of the scaffolds directly. Future studies will focus on using these hydrogels as bioinks to produce 3D printed scaffolds for cell studies.

MPP07

Natural Compounds Modulates Anti-apoptotic Functions of Hsp70 in Prostate Cancer Cells

Brittany Hollins, Sanjay Kumar, James Stokes III, Trentyn Shaw, and Manoj Mishra*

Cancer Biology Research and Training, Department of Biological Sciences, Alabama State University, Montgomery, Alabama 36104. *Email: mmishra@alasu.edu

Prostate cancer is the third most common cause of cancer related mortality in men. There are several available forms of treatment for patients with prostatic cancer, however, treatments with selective procedures such as chemotherapy can lead to multiple changes in DNA structure and gene expression causing the disease to become therapeutically resistant. Therapeutic resistance is the underlying basis for most cancer deaths, promoting a targeted therapy regimen for various cancers.  Studies show that targeting hsp70 may be an alternative strategy for prostate cancer (PCa) treatment. In this study, we hypothesize that natural compounds such as resveratrol (RES) and staurosporine (STS) exposure suppresses anti-apoptotic functions of Hsp70 in prostate cancer cells. Therefore, the long term goal of this investigation is to study the roles of natural compounds in modulating Hsp70 expression and it’s function in prostate cancer cells. To achieve this goal, we used the prostate cancer cell line “PC3” (derived from a metastatic site of bone cancer, grade IV PCa, of a 62 year old caucasian male). Briefly, cells were grown, treated, and incubated at 37˚C in 5.0% CO2 with RES (100uM) and STS (1uM) for 16 hours. After incubation, cells were harvested and different parameters were analyzed such as cell viability, cell morphology, cell cycle, expression of Hsp70, and mitochondrial membrane potential. Our preliminary findings suggest that RES  and STS modulates the expression of Hsp70 in PC3 cells, that in turn sensitizes the PC3 cells. Therefore, Hsp70 may be a possible target for prostate cancer therapy.

MPP08

3D Bone Tissue Scaffolds: A Comparison of Two Fabrication Methods

Jaketta Murphy1 and Derrick Dean2,3,*

1Department of Biological Sciences, 2Biomedical Engineering Program and 3Integrated Bioengineering and Advanced Materials Center, Alabama State University, Montgomery, Alabama 36104. *Email: ddean@alasu.edu

The field of tissue engineering has seen explosive growth over the last decade.  This growth is driven in part by the need to replace or repair damaged tissues and organs.   A critical step in the tissue engineering cycle is the development of a scaffold that mimics the characteristics of the extracellular matrix, ECM.  Some of the key requirements of an effective scaffold include: (1) biocompatibility with host tissue; (2) high degree of interconnected porosity for ingrowth and movement of cells, and flow of nutrients and waste; (3) 3-dimensionality; (4) surface chemistry that promotes cell adhesion, proliferation and differentiation; (5) mechanical properties that match those of the host tissue.  The objective of our study is to investigate the effect of two methods for fabricating 3-dimensional scaffolds on the structure, function and cell viability of polymeric bone tissue scaffolds.  The project is composed of three phases; Phase 1 involves scaffold fabrication via particulate leaching; Phase 2 involves scaffold fabrication using 3-D printing and phase 3 involves investigation of cell viability. We have fabricated polycaprolactone (PCL) samples to mimic the structure and properties of bone tissue using a particulate leaching technique.  Solution cast samples dispersed with hydroxyapatite, HA or bioglass (BG) into PCL solutions, were prepared using a particulate leaching method.  Percentages of the HA and BG ranged from 1 to 5 weight %.  The composition of the scaffold and the foams was confirmed by FT-IR, which featured a strong peak at 1730 cm-1, attributed to the carbonyl group in PCL and a peak at 1040 cm-1, due to the P-O bond in HA and BG, and the crystallinity confirmed by differential scanning calorimetry (DSC).  The crystallinity was highest for the HA samples.   Dynamic mechanical analysis of the sample indicated that the samples stiffness of the samples increased as the HA and BG content increased.  Future work will focus on fabricating scaffolds by 3-D printing and comparing the cell viability for each scaffold.

MPP09

The Effects of a UCBL and Shoe Insert Foot Orthoses on the Joint Kinematics of those with Flexible Flatfeet

Juliana Lynn, Zipporah Gunn, Blake Steczkowski, and Adetoun Komolafe*

Department of Prosthetics and Orthotics, Alabama State University, Montgomery, Alabama 36104. *Email: tounkomo@gmail.com

Flexible flatfoot is a condition in which a person’s foot presents with heel valgus, medial arch flattening and forefoot abduction, usually resulting in the loss of shock absorption and force dispersions that would typically be present in normal arched feet. A University of California Berkely Lab Orthosis (UCBL) can be used to control the hindfoot, while maintaining the shape of the medial longitudinal arch; it is predominantly the orthosis indicated for controlling this deformity. Unlike theUCBL, theshoe insert foot orthosis is much less controlling, allowing for a more intrinsiccontrol of foot alignment.More research is needed to effectively evaluate the clinical application of the UCBL and shoe insert foot orthosis for the control of flexible flatfeet. One subject was selected from a sample of convenience. Castings and modifications were made consistent with the NYU fabrication manual. The subject walked with or without an intervention on the Gait Real time Analysis Interactive Laboratory (GRAIL) system for 5 trials. Joint kinematics and kinetics were recorded for each trial. Results indicated that the UCBL had more effect on the joint kinematics of the knee, while the insert had considerable effects on the ankle. Ground reaction forces did not show significant differences (P<0.05). Power and Moments were significantly affected across the knee and ankle joints using both interventions. This has to do with the interventions effect on the alignment of the joints. The Ground reaction forces showed no significant differences when comparing interventions. Additional research with larger sample sizes is needed though in order to verify these results.

Bandholm T, Boysen L, Haugaard S, Zebis MK, and Bencke J (2008) Foot Medial Longitudinal-Arch Deformation During Quiet Standing and Gaitin Subjects with Medial Tibial Stress Syndrome. J. Foot Ankle Surgery, 47(2),89-95. doi:10.1053/j.jfas.2007.10.015

Hösl M, Böhm H, and Döderlein L (2013) Doesexcessive flat foot deformity affect function? A comparison between symptomatic and asymptomatic pediatric flat feet using the Oxford Foot Model. Gait & Posture, 38. doi:10.1016/j.gaitpost.2013.07.070

Zhai JN, Qiu YS, and Wang J (2016) Effects of orthoticinsoles on adults with flexible flat foot under different walking conditions. J. Physical Therapy Sci., 28(11), 3078-3083. doi:10.1589/jpts.28.3078

Zhai JN, Wang J, and Qiu Y S (2017) Plantar pressure differences among adults with mild flexible flat foot, severef lexible flat foot and normal foot when walking on level surface, walking upstairs and downstairs. J Physical Therapy Sci., 29(4), 641646. doi:10.1589/jpts.29.641

MPP10

Fabrication of a Low-cost Prosthetic Knee using Recycled Materials

Aaron Schmersal and Adetoun Komolafe*

Department of Prosthetics and Orthotics, Alabama State University, Montgomery, Alabama 36104. *Email: tounkomo@gmail.com

Approximately 30-million amputees live in low-income locations; 85-95% of this population have little to no access to prosthetic care. When these amputees do receive appropriate care, the componentry selected for the prosthesis is often expensive or inadequate for daily living(Chu, 2015). While there is an abundance of low-cost prosthetic foot options for amputees in developing nations, there is a dearth of low-cost prosthetic knees. (Hamner, Narayan, Rappin, & Donaldson, 2015). The on-site production of an effective polycentric knee using local recyclable materials would be a boon to the amputee population of the developing world. A protocol that could be followed by prosthetists working in developing nations could allow for the fabrication of a 4-bar knee, using simple, readily available materials. The goal of this project is to create a step-by-step guide for the production of a low-cost prosthetic knee; in this case, using High Density Polyethylene (HDPE). The fabrication process started with the production of a foam model. The foam model was placed into a “flask” and packed tightly with “green sand”. Molten aluminum was then poured into the flask to form a mold for production of the final pieces.  The aluminum mold was filled with shredded HDPE scrap and placed in an oven to melt the plastic.  Once cooled, the plastic parts were smoothed and assembled to form the final product.(Howel, 1993).  Future studies would involve project repeatability, and component strength and longevity tests.

Chu J (2015). A cheaper, high-performance prosthetic knee [Online posting].

Hamner S, Narayan V, Rappin N, and Donaldson K (2015). ReMotion Knee: Scaling of an Affordable Prosthetic Knee for Developing Countries. Technologies for Development,137-151. doi:10.1007/978-3-319-16247-8_14

Howell JS (1993). Evaporative Polystyrene Metal Casting Technology: Current Technique and Potential Application. APT Bulletin,25(3/4), 60. doi:10.2307/1504468

MPP11

Growth of Fibroblast Cells on Hydrogels for Tissue Engineering

Diana Richardson, Komal Vig*, and Sameer Joshi

Center for Nanobiotechnology Research, Alabama State University, Montgomery, Alabama 36104. *Email: komalvig@alasu.edu

Tissue engineering involves the use of engineering methods, favorable biochemical factors, and cells to improve tissues. Scaffolds are used in tissue engineering for the formation of new feasible tissue. There are many front line biological scaffolds, but hydrogels have become one of the most essential due to their high water content, porous structure, and excellent flexibility. These scaffolds provide wound surface hydration and moisture. Wound recovery, bone and ligament convalesce, and cell therapeutics are some of the biomedical tests that hydrogels have assisted. Hydrogels have also created a method for drug delivery because of their similarity to natural skin and biocompatibility. Alginate hydrogels have proven mechanical properties with minimum toxicity. In this study, alginate hydrogels are being tested for cell growth of keratinocyte cells. 1% alginate was prepared by mixing 1g alginate in 99ml distilled water, and then stirred for 30 minutes. 1% CaCl2 solution was prepared by mixing 1g CaCl2 in 99ml distilled water. Alginate hydrogels were prepared by adding 20µl of 1% CaCl2 into 100µl of 1% alginate. The cell development proficiency on fibroblast cells are being tested using this concentration in a 96 well plate of over a course of 21 days. The cells will be observed for a variety of things such as viability, absorbency, and cell proliferation. MTT assay will be used to measure the cellular viability on each hydrogel. Generally, this examination points on recognizing hydrogels for tissue designing and their applications in the field. Fibroblast cells have grown tremendously with the use of alginate hydrogels. The initial purpose of the study was to observe cell growth of fibroblasts on hydrogels. It was observed that fibroblast cells can be grown on hydrogels. MTT assay is currently being done to measure the cellular viability on each hydrogel. Cell growth on hydrogels will also undergo tests with DAPI (4', 6-diamidino-2-phenylindole) and neutral red dye uptake. NIH under the Research Initiative for Scientific Enhancement (RISE) program funded this experiment.