Medicine and Health Sciences Commons^™

Comparative Analysis Of 3d Printed Denture Resins With Traditional Denture Materials At The Micro Level, Aneeza Hussain, Caleb Beckwith, Gaffar Gailani

Publications and Research

The aim of this experiment was to evaluate and identify compression strength between traditionally manufactured acrylic dentures and additive manufacturing resin dentures. Specifically, the dentures produced by Uhler Dental, its Reveal line were compared against samples produced on the Formlabs Form 2 SLA, Stereolithography, 3D printer using their Denture Teeth A2 resin to test compression strength to assure they are compatible with the occlusal forces in the oral cavity. Using the ZwickRoell tensile testing machine, it appeared that the acrylic dentures were half as strong as the resin dentures. Then we went ahead to and did a comparative analysis under …

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …

No Ordinary Proteins: Adsorption And Molecular Orientation Of Monoclonal Antibodies, Ankit D. Kanthe, Andrew Ilott, Mary Krause, Songyan Zheng, Jinjiang Li, Wei Bu, Mrinal K. Bera, Binhua Lin, Charles Maldarelli, Raymond S. Tu

Publications and Research

The interaction of monoclonal antibodies (mAbs) with air/water interfaces plays a crucial role in their overall stability in solution. We aim to understand this behavior using pendant bubble measurements to track the dynamic tension reduction and x-ray reflectivity to obtain the electron density profiles (EDPs) at the surface. Native immunoglobulin G mAb is a rigid molecule with a flat, “Y” shape, and simulated EDPs are obtained by rotating a homology construct at the surface. Comparing simulations with experimental EDPs, we obtain surface orientation probability maps showing mAbs transition from flat-on Y-shape configurations to side-on or end-on configurations with increasing concentration. …

Association Of X-Ray Absorptiometry Body Composition Measurements With Basic Anthropometrics And Mortality Hazard, Nir Y. Krakauer, Jesse C. Krakauer

Publications and Research

Dual-energy X-ray absorptiometry (DEXA) is a non-invasive imaging modality that can estimate whole-body and regional composition in terms of fat, lean, and bone mass. We examined the ability of DEXA body composition measures (whole-body, trunk, and limb fat mass and fat-free mass) to predict mortality in conjunction with basic body measures (anthropometrics), expressed using body mass index (BMI) and a body shape index (ABSI). We used data from the 1999–2006 United States National Health and Nutrition Examination Survey (NHANES), with mortality follow-up to 2015. We found that all DEXA-measured masses were highly correlated with each other and with ABSI and …

A Systematic Review And Meta-Analysis On The Efficacy Of Stem Cell Therapy On Bone Brittleness In Mouse Models Of Osteogenesis Imperfecta, Lauren Battle, Shoshana Yakar, Alessandra Carriero

Publications and Research

There is no cure for osteogenesis imperfecta (OI), and current treatments can only partially correct the bone phenotype. Stem cell therapy holds potential to improve bone quality and quantity in OI. Here, we conduct a systematic review and meta-analysis of published studies to investigate the efficacy of stem cell therapy to rescue bone brittleness in mouse models of OI. Identified studies included bone marrow, mesenchymal stem cells, and human fetal stem cells. Effect size of fracture incidence, maximum load, stiffness, cortical thickness, bone volume fraction, and raw engraftment rates were pooled in a random-effects meta-analysis. Cell type, cell number, injection …

Acute Effect Of High‑Definition And Conventional Tdcs On Exercise Performance And Psychophysiological Responses In Endurance Athletes: A Randomized Controlled Trial, Daniel Gomes Da Silva Machado, Marom Bikson, Abhishek Datta, Egas Caparelli‑Dáquer, Gozde Unal, Abrahão F. Baptista, Edilson Serpeloni Cyrino, Li Min Li, Edgard Morya, Alexandre Moreira, Alexandre Hideki Okano

Publications and Research

Transcranial direct current stimulation (tDCS) has been used aiming to boost exercise performance and inconsistent findings have been reported. One possible explanation is related to the limitations of the so-called “conventional” tDCS, which uses large rectangular electrodes, resulting in a diffuse electric field. A new tDCS technique called high-definition tDCS (HD-tDCS) has been recently developed. HD-tDCS uses small ring electrodes and produces improved focality and greater magnitude of its aftereffects. This study tested whether HD-tDCS would improve exercise performance to a greater extent than conventional tDCS. Twelve endurance athletes (29.4 ± 7.3 years; 60.15 ± 5.09 ml kg− 1 min− …

Detection Methods And Clinical Applications Of Circulating Tumor Cells In Breast Cancer, Hongyi Zhang, Xiaoyan Lin, Yuan Huang, Minghong Wang, Chunmei Cen, Shasha Tang, Marcia R. Dique, Lu Cai, Manuel A. Luis, Jillian Smollar, Yuan Wan, Fengfeng Cai

Publications and Research

Circulating Tumor Cells (CTCs) are cancer cells that split away from the primary tumor and appear in the circulatory system as singular units or clusters, which was first reported by Dr. Thomas Ashworth in 1869. CTCs migrate and implantation occurs at a new site, in a process commonly known as tumor metastasis. In the case of breast cancer, the tumor cells often migrate into locations such as the lungs, brain, and bones, even during the early stages, and this is a notable characteristic of breast cancer. Survival rates have increased significantly over the past few decades because of progress made …

Nanoanalytical Analysis Of Bisphosphonate-Driven Alterations Of Microcalcifications Using A 3d Hydrogel System And In Vivo Mouse Model, Jessica L. Ruiz, Joshua D. Hutcheson, Luis Cardoso, Amirala Bakhshian Nik, Alexandra Condado De Abreu, Tan Pham, Fabrizio Buffolo, Sara Busatto, Stefania Frederici, Andrea Ridolfi, Masanori Aikawa, Sergio Bertazzo, Paolo Bergese, Sheldon Weinbaum, Elena Aikawa

Publications and Research

Vascular calcification predicts atherosclerotic plaque rupture and cardiovascular events. Retrospective studies of women taking bisphosphonates (BiPs), a proposed therapy for vascular calcification, showed that BiPs paradoxically increased morbidity in patients with prior acute cardiovascular events but decreased mortality in event-free patients. Calcifying extracellular vesicles (EVs), released by cells within atherosclerotic plaques, aggregate and nucleate calcification. We hypothesized that BiPs block EV aggregation and modify existing mineral growth, potentially altering microcalcification morphology and the risk of plaque rupture. Three-dimensional (3D) collagen hydrogels incubated with calcifying EVs were used to mimic fibrous cap calcification in vitro, while an ApoE−/− mouse was used …

Slowing The Spread Of Covid-19: Review Of “Social Distancing” Interventions Deployed By Public Transit In The United States And Canada, Camille Kamga, Penny Eickemeyer

Publications and Research

This paper presents a review of social distancing measures deployed by transit agencies in the United States and Canada during the COVID-19 pandemic and discusses how specific operators across the two countries have implemented changes. Challenges and impacts on their operations are also provided.

Social distancing is one of the community mitigation measures traditionally implemented during influenza pandemics and the novel coronavirus pandemic. Research has shown that social distancing is effective in containing the spread of disease. This is applicable to the current situation with the novel coronavirus, given the lack of effective vaccines and treatments in the United States …

A Bisphosphonate With A Low Hydroxyapatite Binding Affinity Prevents Bone Loss In Mice After Ovariectomy And Reverses Rapidly With Treatment Cessation, Abigail A. Coffman, Jelena Basta-Pljakic, Rosa M. Guerra, Frank H. Ebetino, Mark W. Lundy, Robert J. Majeska, Mitchell B. Schaffler

Publications and Research

Bisphosphonates (BPs) are a mainstay of osteoporosis treatment; however, concerns about bone health based on oversuppression of remodeling remain. Long-term bone remodeling suppression adversely affects bone material properties with microdamage accumulation and reduced fracture toughness in animals and increases in matrix mineralization and atypical femur fractures in patients. Although a “drug holiday” from BPs to restore remodeling and improve bone quality seems reasonable, clinical BPs have long functional half-lives because of their high hydroxyapatite (HAP) binding affinities. This places a practical limit on the reversibility and effectiveness of a drug holiday. BPs with low HAP affinity and strong osteoclast inhibition …

Age And Sex Differences In Load-Induced Tibial Cortical Bone Surface Strain Maps, Alessandra Carriero, Behzad Javaheri, Neda Bassir Kazeruni, Andrew A. Pitsillides, Sandra J. Shefelbine

Publications and Research

Bone adapts its architecture to the applied load; however, it is still unclear how bone mechano-adaptation is coordinated and why potential for adaptation adjusts during the life course. Previous animal models have suggested strain as the mechanical stimulus for bone adaptation, but yet it is unknown how mouse cortical bone load-related strains vary with age and sex. In this study, full-field strain maps (at 1 N increments up to 12 N) on the bone surface were measured in young, adult, and old (aged 10, 22 weeks, and 20 months, respectively), male and female C57BL/6J mice with load applied using a …

Restoration Of Bone Material And Microstructural Properties After Long-Term Remodeling Suppression, Abigail A. Coffman

Dissertations and Theses

Anti-resorptive drugs, principally bisphosphonates (BPs), are the mainstay of osteoporosis treatment. They work by inhibiting bone resorption/remodeling, thus preventing bone loss. However, long-term suppression of bone resorption adversely affects bone tissue mechanical properties, even while conserving bone mass. Lack of remodeling leads to accumulation of fatigue-induced microdamage, altered matrix mineralization and reduction in normal bone tissue heterogeneity, causing impaired strength and fracture toughness. The most severe consequence to patients, while rare, is Atypical Femur Fractures (i.e., complete fatigue fractures of the femoral shaft). To counteract the effects of long-term remodeling suppression, a temporary break in BP treatment (a "drug holiday) …

Osteocyte Activity And Skeletal Muscle Relative Gene Expression Profiling After Short-Term Muscle Paralysis, Michelle Gelbs

Dissertations and Theses

Mechanical loading is essential for maintaining bone tissue. Reduced mechanical loading has been shown to have a negative effect on bone, and can result in the development of disuse osteoporosis. Disuse models of muscle inactivity and immobilization, like the Botox model used in this study, result in changes in the bone microarchitecture, the mechanisms behind which are not fully understood. In a previous four-week Botox disuse study, skeletally mature 20- week-old rats experienced degradation of intracortical bone, increased vascular porosity, and decreased osteocyte lacunar density in the tibiae. The focus of this study was to explicate a potential source of …

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …

Development Of An Injectable Methylcellulose Hydrogel System For Nucleus Pulposus Repair And Regeneration, Nada A. Haq-Siddiqi

Dissertations and Theses

Low back pain is the most common cause of disability in the world and is often caused by degeneration or injury of the intervertebral disc (IVD). The IVD is a complex, fibrocartilaginous tissue that allows for the wide range of spinal mobility. Disc degeneration is a progressive condition believed to begin in the central, gelatinous nucleus pulposus (NP) region of the tissue, for which there are few preventative therapies. Current therapeutic strategies include pain management and exercise, or surgical intervention such as spinal fusion, none of which address the underlying cause of degeneration. With an increasingly aging population, the socioeconomic …