Biomedical Engineering and Bioengineering Commons^™

Reducing Biomass Recalcitrance By Heterologous Expression Of A Bacterial Peroxidase In Tobacco (Nicotiana Benthamiana), Ayalew Ligaba-Osena, Bertrand Hankoua, Kay Dimarco, Robert Pace, Mark Crocker, Jesse Mcatee, Nivedita Nagachar, Ming Tien, Tom L. Richard

Center for Applied Energy Research Faculty and Staff Publications

Commercial scale production of biofuels from lignocellulosic feed stocks has been hampered by the resistance of plant cell walls to enzymatic conversion, primarily owing to lignin. This study investigated whether DypB, the lignin-degrading peroxidase from Rodococcus jostii, depolymerizes lignin and reduces recalcitrance in transgenic tobacco (Nicotiana benthamiana). The protein was targeted to the cytosol or the ER using ER-targeting and retention signal peptides. For each construct, five independent transgenic lines were characterized phenotypically and genotypically. Our findings reveal that expression of DypB in the cytosol and ER does not affect plant development. ER-targeting increased protein accumulation, and …

Synthesis Of Regioselectively Acylated Quercetin Analogues With Improved Antiplatelet Activity, Yu Duan, Na Sun, Min Xue, Xiaolan Wang, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

The aim of the present study was to report on a complete synthetic approach, namely benzylation-hydrolysis-acylation-hydrogenation, to the synthesis of regioselectively acylated quercetin analogues using low-cost rutin as a starting material. Three quercetin analogues, quercetin-3-O-propionate (Q-pr), quercetin-3-O-butyrate (Q-bu) and quercetin-3-O-valerate (Q-va), containing 3-, 4- and 5-carbon aliphatic acyl chains, respectively, were synthesized and characterized with ¹H nuclear magnetic resonance (NMR), ¹³C NMR and mass spectrometry. Compared with quercetin, all three analogues exhibited improved lipophilicity. The lipophilicity of the analogue increased with increasing acyl chain length. Q-va exhibited the highest lipophilicity among the three analogues, but a lower water …

Tuning Properties Of Poly(Ethylene Glycol)-Block-Poly(Simvastatin) Copolymers Synthesized Via Triazabicyclodecene, Theodora A. Asafo-Adjei, Thomas D. Dziubla, David A. Puleo

Biomedical Engineering Faculty Publications

Simvastatin was polymerized into copolymers to better control drug loading and release for therapeutic delivery. When using the conventional stannous octoate catalyst in ring-opening polymerization (ROP), reaction temperatures ≥ 200 °C were required, which promoted uncontrollable and undesirable side reactions. Triazabicyclodecene (TBD), a highly reactive guanidine base organocatalyst, was used as an alternative to polymerize simvastatin. Polymerization was achieved at 150 °C using 5 kDa methyl-terminated poly(ethylene glycol) (mPEG) as the initiator. ROP reactions with 2 kDa or 550 Da mPEG initiators were also successful using TBD at 150 °C instead of stannous octoate, which required a higher reaction temperature. …

Titanium Addition Influences Antibacterial Activity Of Bioactive Glass Coatings On Metallic Implants, Omar Rodriguez, Wendy Stone, Emil H. Schemitsch, Paul Zalzal, Stephen Waldman, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

In an attempt to combat the possibility of bacterial infection and insufficient bone growth around metallic, surgical implants, bioactive glasses may be employed as coatings. In this work, silica-based and borate-based glass series were synthesized for this purpose and subsequently characterized in terms of antibacterial behavior, solubility and cytotoxicity. Borate-based glasses were found to exhibit significantly superior antibacterial properties and increased solubility compared to their silica-based counterparts, with BRT0 and BRT3 (borate-based glasses with 0 and 15 mol% of titanium dioxide incorporated, respectively) outperforming the remainder of the glasses, both borate and silicate based, in these respects. Atomic Absorption Spectroscopy …

Potency And Cytotoxicity Of A Novel Gallium-Containing Mesoporous Bioactive Glass/Chitosan Composite Scaffold As Hemostatic Agents, Sara Pourshahrestani, Ehsan Zeimaran, Nahrizul Adib Kadri, Nicola Gargiulo, Hassan Mahmood Jindal, Sangeetha Vasudevaraj Naveen, Shamala Devi Sekaran, Tunku Kamarul, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Chitosan-based hemostats are promising candidates for immediate hemorrhage control. However, they have some disadvantages and require further improvement to achieve the desired hemostatic efficiency. Here, a series of 1% Ga2O3-containing mesoporous bioactive glass-chitosan composite scaffolds (Ga-MBG/CHT) were constructed by the lyophilization process and the effect of various concentrations of Ga-MBG (10, 30, and 50 wt %) on the hemostatic function of the CHT scaffold was assessed as compared to that of Celox Rapid gauze (CXR), a current commercially available chitosan-coated hemostatic gauze. The prepared scaffolds exhibited >79% porosity and showed increased water uptake compared to that in CXR. The results …

Raman Spectral Variation For Human Fingernails Of Postmenopausal Women Is Dependent On Fracture Risk And Osteoporosis Status, J. R. Beattie, M. C. Caraher, N. M. Cummins, O. M. O'Driscoll, R. Eastell, S. H. Ralston, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Patients diagnosed with osteoporosis have reported loss of fingernail resilience as the disease progresses. Keratin is the predominant protein in human nail tissue, and its structure has been postulated to be different in fingernails clipped from subjects who have sustained fragility fractures and those who have not, which may offer a window into the donor's bone health. This study was designed to qualify these differences, which may lead to the development of a novel screening tool for fracture risk. Raman spectroscopy was used to measure the fingernails of 633 postmenopausal women who presented at six fracture clinics located across the …

Common Treatments And Procedures Used For Fractures Of The Distal Radius And Scaphoid: A Review, Basel A. Khader, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

The distal radius and the scaphoid are the most commonly injured carpal bones among both active adults and the osteoporotic elderly. The purpose of surgical treatment is to restore form and function to the wrist. Depending on the nature of the fracture, either topical procedures or invasive surgery can be applied. This article critiques the treatments currently used for fixation of wrist fractures in order to drive the development of new materials to improve patient outcomes.

Shear Driven Micro-Fluidic Pump For Cardiovascular Applications, Nihad E. Daidzic

Aviation Department Publications

A valveless shear-driven micro-fluidic pump design (SDMFP) for hemodynamic applications is presented in this work. One of the possible medical and biomedical applications is in-vivo hemodynamic (human blood circulation) support/assist. One or more SDMFPs can be inserted/implanted into vascular lumens in a form of a stent/duct in series and/or in parallel (bypass duct) to support blood circulation in-vivo. A comprehensive review of various micro-pump designs up to about mid 2000’s is given in [1,2]. Many of micropump designs considered are not suitable for in-vivo or even in-vitro medical/biomedical applications.

Operating principles, design, and SDMFP features are given in [3]. A …

Genetic Code Expansion In Biochemical Investigations And Biomedical Applications, Nanxi Wang

Department of Chemistry: Dissertations, Theses, and Student Research

Genetic code expansion provides a powerful tool for site-specific incorporation of unnatural amino acids (unAAs) with novel biochemical and physiological properties into proteins in live cells and organisms. To achieve this, a nonsense codon suppression system, which consists of an orthogonal aminoacyl-tRNA synthetase (aaRS) and tRNA pair that specifically decodes a nonsense codon (e.g., amber codon and quadruplet codon) with an unAA but do not “cross talk” with their endogenous counterparts, was established. This Ph.D. thesis presents our efforts on evolution and application of nonsense codon suppression systems for biochemical and biomedical investigations.

In Chapter 1, a brief overview of …

Polysaccharide Fabrication Platforms And Biocompatibility Assessment As Candidate Wound Dressing Materials, Donald C. Aduba Jr., Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Wound dressings are critical for wound care because they provide a physical barrier between the injury site and outside environment, preventing further damage or infection. Wound dressings also manage and even encourage the wound healing process for proper recovery. Polysaccharide biopolymers are slowly becoming popular as modern wound dressings materials because they are naturally derived, highly abundant, inexpensive, absorbent, non-toxic and non-immunogenic. Polysaccharide biopolymers have also been processed into biomimetic platforms that offer a bioactive component in wound dressings that aid the healing process. This review primarily focuses on the fabrication and biocompatibility assessment of polysaccharide materials. Specifically, fabrication platforms …

A Novel Tantalum-Containing Bioglass. Part I. Structure And Solubility, Adel Mf Alhalawani, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bio glasses are employed for surgical augmentation in a range of hard tissue applications. Tantalum is a bioactive and biocompatible transition metal that has been used as an orthopedic medical device. It has a range of biological and physical properties that make its incorporation into ionic form into bioactive glass systems promising for various clinical applications. The work herein reports the characterization and properties of novel tantalum-containing glasses. A series of glasses based on the system 48SiO₂-(36-X)ZnO-6CaO-8SrO-2P₂O₅-XTa₂O₅ with X varying from 0 mol% (TA0) to 0.5 mol% (TA2) were synthesized. The …

Toxicity Evaluation Of Magnetic Hyperthermia Induced By Remote Actuation Of Magnetic Nanoparticles In 3d Micrometastasic Tumor Tissue Analogs For Triple Negative Breast Cancer, Nathanael A. Stocke, Pallavi Sethi, Amar Jyoti, Ryan Chan, Susanne M. Arnold, J. Zach Hilt, Meenakshi Upreti

Chemical and Materials Engineering Faculty Publications

Magnetic hyperthermia as a treatment modality is acquiring increased recognition for loco-regional therapy of primary and metastatic lung malignancies by pulmonary delivery of magnetic nanoparticles (MNP). The unique characteristic of magnetic nanoparticles to induce localized hyperthermia in the presence of an alternating magnetic field (AMF) allows for preferential killing of cells at the tumor site. In this study we demonstrate the effect of hyperthermia induced by low and high dose of MNP under the influence of an AMF using 3D tumor tissue analogs (TTA) representing the micrometastatic, perfusion independent stage of triple negative breast cancer (TNBC) that infiltrates the lungs. …

Characterization And Fracture Property Of Different Strontium-Containing Borate-Based Glass Coatings For Ti6al4v Substrates, Yiming Li, Ali Matinmanesh, Declan J. Curran, Emil H. Schemitsch, Paul Zalzal, Marcello Papini, Anthony W. Wren, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work considered the effect of increasing Strontium ion (Sr²⁺) content on the structure of a series of glasses based on the B₂O₃-P₂O₅-CaCO₃-Na₂CO₃-TiO₂-SrCO₃ series and their resultant fracture toughness when coated onto a surgical metal substrate. Six glasses with increasing Sr²⁺ content (0 to 25 mol%) were synthesized and subsequently characterized by X-ray Diffraction (XRD), Differential Thermal Analysis (DTA) and both Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR) and Raman Spectroscopy. These techniques confirmed that increased Sr²⁺ content induced …

A Novel Tantalum-Containing Bioglass. Part Ii. Development Of A Bioadhesive For Sternal Fixation And Repair, Adel Mf Alhalawani, Cina Mehrvar, Wendy Stone, Stephen D. Waldman, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

With over a million median sternotomy surgeries performed worldwide every year, sternal wound complications have posed a serious risk to the affected patients. A rigid therapeutic sternal fixation device has therefore become a necessity. In this work, the incorporation of up to 0.5 mol% of tantalum pentoxide (Ta₂O₅), in exchange for zinc oxide (ZnO), into the SiO₂-ZnO-CaO-SrO-P₂O₅ glass system is presented. The effect of Ta incorporation on the physical, chemical and biological properties of the glass polyalkenoate cements (GPCs) prepared from them have been presented in this manuscript. The data obtained …

Engineering A Fluorescent Protease Sensor For In Vivo Protein Detection, Thomas C. Kinard

Honors Scholar Theses

This report details the results of an ongoing project to engineer a mutant form of Red Fluorescent Protein (RFP) variant mCherry that acts as a real-time in vivo protease sensor. The sought-after mutant only becomes fluorescent when exposed to Tobacco Etch Virus (TEV) Protease, this system’s model protease. This will be accomplished via the insertion of the TEV Protease Recognition Site (TEV-PRS) in such a position that, before cleavage, will prevent the protein from folding to fluorescent conformation, but upon cleavage, will allow for fluorescent conformation to occur. The cylindrical structure of the protein, composed of beta-pleated sheets, contains “loops” …

Idiosyncratic Drug-Induced Liver Injury (Idili): Potential Mechanisms And Predictive Assays, Alexander D. Roth, Moo-Yeal Lee

Chemical & Biomedical Engineering Faculty Publications

Idiosyncratic drug-induced liver injury (IDILI) is a significant source of drug recall and acute liver failure (ALF) in the United States. While current drug development processes emphasize general toxicity and drug metabolizing enzyme- (DME-) mediated toxicity, it has been challenging to develop comprehensive models for assessing complete idiosyncratic potential. In this review, we describe the enzymes and proteins that contain polymorphisms believed to contribute to IDILI, including ones that affect phase I and phase II metabolism, antioxidant enzymes, drug transporters, inflammation, and human leukocyte antigen (HLA). We then describe the various assays that have been developed to detect individual reactions …

Sugar Versus Lipid For Sustainable Biofuels, Yaşar Demirel

Yaşar Demirel Publications

Introduction

First‐generation biofuels, namely, ethanol and biodiesel, have led to far reaching impact on the peoples’ life world‐wide.[1] However, they inter-fere with the food supply chain and may not be sustainable although some of the biomass are converted to biofuels after those biomasses have met the human needs. Still, the first‐generation–based biofuels have proved that sugar and lipid platforms can be an answer to energy security and global warming concerns without the need for new infrastructure for feedstock delivery as well as for biomass‐to‐biofuel conversion tech-nologies. At the same time, we are discovering and assessing the long‐term environmental im-plications on …