Biomedical Engineering and Bioengineering Commons^™

In Vivo Measurement Of Nadh Fluorescence Lifetime In Skeletal Muscle Via Fiber-Coupled Time-Correlated Single Photon Counting, Kathryn M. Priest, Jacob V. Schluns, Nathania Nischal, Colton L. Gattis, Jeffery C. Wolchok, Timothy J. Muldoon

Biomedical Engineering Faculty Publications and Presentations

Nicotinamide adenine dinucleotide (NADH) is a cofactor that serves to shuttle electrons during metabolic processes such as glycolysis, the tricarboxylic acid cycle, and oxidative phosphorylation (OXPHOS). NADH is autofluorescent, and its fluorescence lifetime can be used to infer metabolic dynamics in living cells. Fiber-coupled time-correlated single photon counting (TCSPC) equipped with an implantable needle probe can be used to measure NADH lifetime in vivo, enabling investigation of changing metabolic demand during muscle contraction or tissue regeneration. This study illustrates a proof of concept for point-based, minimally-invasive NADH fluorescence lifetime measurement in vivo. Volumetric muscle loss (VML) injuries were …

The Sexually Dimorphic Role Of Connexin 43 In Bone Remodeling And Disuse-Induced Bone Loss, Gabriel A. Hoppock

Theses and Dissertations

Bone loss is frequently experienced by individuals undergoing long-term disuse, such as prolonged bedrest, immobilization due to paralysis or injury, and conditions such as spaceflight. Under normal physiological conditions, bone remodeling is balanced by bone-forming osteoblasts and bone-resorbing osteoclasts, and the activity of osteoblasts and osteoclasts is orchestrated by osteocytes. Osteocytes are the most abundant cell type found in bone and ample evidence suggests they are bone’s main mechanosensory cell type. Therefore, understanding osteocyte biology and responses to mechanical signals, or lack thereof during unloading, may lead to new therapeutic targets to combat bone loss during disuse. Previous data has …

Method For Continuous Fabrication Of Multi-Functional Nanogels, Hu Yang, Da Huang

Patents

Nanogels and methods of synthesizing and using these nanogels are provided. The nanogels are formed by mixing a building block (e.g., polymer), crosslinker, preferably a target (e.g., biomedical compound or molecule), and a solvent in a multi-inlet vortex mixer, so as to cause the polymer and crosslinker to react and form a chemically crosslinked polymer network. In embodiments including a target, the target will be interspersed in and among that network and can be physically embedded and/or chemically bound therein.

The Effect Of Phase-Separated Microstructures On Cell Migration In 3d Dextran Hydrogels, Jenifer Sidhwa

Honors Theses and Capstones

No abstract provided.

Flexible Fitting Of Alphafold2-Predicted Models To Cryo-Em Density Maps Using Elastic Network Models: A Methodological Affirmation, Maytha Alshammari, Jing He, Willy Wriggers

Computer Science Faculty Publications

Motivation: This study investigates the flexible refinement of AlphaFold2 models against corresponding cryo-electron microscopy (cryo-EM) maps using normal modes derived from elastic network models (ENMs) as basis functions for displacement. AlphaFold2 generally predicts highly accurate structures, but 18 of the 137 models of isolated chains exhibit a TM-score below 0.80. We achieved a significant improvement in four of these deviating structures and used them to systematically optimize the parameters of the ENM motion model.

Results: We successfully refined four AlphaFold2 models with notable discrepancies: lipid-preserved respiratory supercomplex (TM-score increased from 0.52 to 0.69), flagellar L-ring protein (TM-score increased from 0.53 …

Gamma Amplitude-Envelope Correlations Are Strongly Elevated Within Hyperexcitable Networks In Focal Epilepsy, Manoj Raghavan, Jared Pilet, Chad Carlson, Christopher T. Anderson, Wade Mueller, Sean Lew, Candida Ustine, Priyanka Shah-Basak, Vahab Youssofzadeh, Scott A. Beardsley

Biomedical Engineering Faculty Research and Publications

Methods to quantify cortical hyperexcitability are of enormous interest for mapping epileptic networks in patients with focal epilepsy. We hypothesize that, in the resting state, cortical hyperexcitability increases firing-rate correlations between neuronal populations within seizure onset zones (SOZs). This hypothesis predicts that in the gamma frequency band (40–200 Hz), amplitude envelope correlations (AECs), a relatively straightforward measure of functional connectivity, should be elevated within SOZs compared to other areas. To test this prediction, we analyzed archived samples of interictal electrocorticographic (ECoG) signals recorded from patients who became seizure-free after surgery targeting SOZs identified by multiday intracranial recordings. We show that …

Multi-Functional Gelatin-Dithiolane Hydrogels For Tissue Engineering, Saad Asim

Dissertations, Master's Theses and Master's Reports

Biomaterials that integrate multiple functionalities, mimic the extracellular matrix (ECM) microenvironment to support cellular growth, and adhere robustly to damaged tissues are highly needed to advance tissue engineering. Protein-based biomaterials are promising due to their inherent biocompatibility, biomimicry, biodegradation, and cell-supportive properties. Herein, by leveraging the unique ability of dithiolanes to generate on-demand in-situ thiols, we developed a new class of dithiolane-modified, protein-based biomaterial that combines unique, seemingly opposing functions for tissue engineering. Dithiolane-modified gelatin, a model protein used herein, enabled photoinitiator-free photo-crosslinking to form multi-functional gelatin-dithiolane (GelDT) hydrogels, which displayed exceptional long-term stability in cell culture media (>28 …

Computational Analysis Of Vascular Aneurysms, Seyedmostafa Rezaeitaleshmahalleh

Dissertations, Master's Theses and Master's Reports

Vascular aneurysms, such as intracranial aneurysms (IAs) and abdominal aortic aneurysms (AAAs), pose significant health risks, particularly upon rupture. Disturbed hemodynamics, characterized by swirling flow patterns, can lead to cellular and structural changes that disrupt normal physiological processes and contribute to destructive vascular remodeling. Integrating hemodynamic analysis into clinical assessments of aneurysms has become crucial, especially through patient-specific computational fluid dynamics (CFD) simulations based on medical imaging. However, the complexity of CFD tools presents challenges in model creation and post-simulation analysis, limiting their accessibility to clinicians.
This project aimed to advance aneurysm management by exploring the role of intraluminal thrombus …

An Fpga-Based Eit System For Deep Space Medical Imaging, Kendall R. Farnham

Dartmouth College Ph.D Dissertations

Dangers associated with high radiation and microgravity exposure in space are critical challenges inhibiting us from exploring deep space and pursuing long-duration missions, as current medical systems are unable to monitor, diagnose, or treat tissue injury within physical spacecraft constraints and communication limits. Ultrasound (US) is the current imaging system used on the International Space Station, but this technology relies on telemedical support (or onboard artificial intelligence/autonomous capabilities) for both operation and diagnosis, posing challenges for crews isolated in deep space. Electrical impedance tomography (EIT) is a non-invasive, non-ionizing technology that produces images of the electrical properties of tissues and …

Matrix Stiffness Sensing By Nascent Adhesions And The Role Of Riam In Adhesion Assembly, Nikhil Mittal

Dissertations, Master's Theses and Master's Reports

Mechanical stiffness of the extracellular matrix (ECM) impacts many cellular functions such as proliferation, migration, and differentiation. ECM stiffness is sensed by a cell via integrin-based focal adhesions (FAs) by changing conformation and biochemical activities of molecules within FAs by the exchange of the force between the ECM and filamentous actin (F-actin). Cells in turn respond to this stiffness by generating traction force that plays an important role in many biological events such as tissue morphogenesis, stem cell differentiation, wound healing, and cancer cell metastasis. The stiffness of the extracellular matrix induces differential tension within integrin-based adhesions. Understanding stiffness sensing …

Mobile Robot Adhesion Methodology And Development Of An Automatous Robot Module, Lauren Baird, Zachariah Stone, Madison Lemons, Jonathon Moody

Williams Honors College, Honors Research Projects

Due to the increasing availability of space travel as not only a scientific exploration but a commercial exploration, there is a need for an onsite repair station that can be deployed in the event of aircraft maintenance, damage, or failure. We have been tasked with researching and creating a prototype of an automatous robot that can be attached to a spacecraft body, move along the surface while avoiding obstacles, scan for damage, 3D print a repair piece, and then make the repair, all without the need of direct human input. Our team, as will be discussed throughout, was tasked with …

Tympanostomy Tube Efficiency Study, Reem Ghumrawi, Kristi Weir

Williams Honors College, Honors Research Projects

The ventilation of the middle ear, crucial for maintaining optimal ear health, is often impeded by factors such as swelling, inflammation, and mucus in the eustachian tubes, particularly during upper respiratory infections or allergies. This issue, prevalent in children due to their narrow and horizontal eustachian tubes, prompts the insertion of tympanostomy tubes by ENT surgeons to establish an alternative airway for pressure equalization and fluid drainage. Despite the common belief in the effectiveness of these tubes, there is a notable dearth of research validating their optimal functionality. This study aims to address this gap by systematically comparing the efficiency …

Salmonella Detection In Food Using A Hek-Htlr5 Reported Cell-Based Sensor, Esma Eser, Victoria A. Felton, Rishi Drolia, Arun K. Bhunia

Biological Sciences Faculty Publications

The development of a rapid, sensitive, specific method for detecting foodborne pathogens is paramount for supplying safe food to enhance public health safety. Despite the significant improvement in pathogen detection methods, key issues are still associated with rapid methods, such as distinguishing living cells from dead, the pathogenic potential or health risk of the analyte at the time of consumption, the detection limit, and the sample-to-result. Mammalian cell-based assays analyze pathogens’ interaction with host cells and are responsive only to live pathogens or active toxins. In this study, a human embryonic kidney (HEK293) cell line expressing Toll-Like Receptor 5 (TLR-5) …

Receptor-Targeted Next-Generation Probiotics Ameliorate Mammalian Colitis, Nicholas L. F. Gallina, Vignesh Nathan, Akshay Krishnakumar, Dongqi Liu, Rishi Drolia, Nicole Irrizary Tardi, Yang Fu, Manalee Samadar, Shivendra Tenguria, Alvin Cai, Ruth Eunice Centeno-Martinez, Timothy A. Johnson, Abigail Cox, Lavanya Reddivari, Bruce Applegate, Xingjian Bai, Luping Xu, Deepti Tanjore, Ramesh Vemulapalli, Rahim Rahimi, Arun K. Bhunia

Biological Sciences Faculty Publications

Introduction: a loss of intestinal barrier function, inflammation, and an elevated expression of epithelial heat shock protein 60 (Hsp60) are features of an inflamed bowel. Probiotics have been used to alleviate colitis-induced pathologies, but offer poor adhesion and adaptation to the diseased gut. We hypothesize that enhancing probiotic adhesion in the inflamed bowel may ameliorate such pathologies. Listeria adhesion protein (LAP; 94-kDa acetaldehyde alcohol dehydrogenase) aids Listeria attachment to the epithelial cells by interacting with the mammalian receptor Hsp60. Bioengineered Lactobacillus casei probiotics (BLPs) expressing LAP showed strong interaction with epithelial Hsp60, a high immunomodulatory response, and sustained epithelial barrier …

Serious Game-Based Training For Improved Utilization Of A Novel Temporalis Emg Interface For Controlling Powered Wheelchairs, Calvin Macdonald

Honors Undergraduate Theses

Amyotrophic lateral sclerosis (ALS) is a terminal neurodegenerative disease that leads to a lack of independent mobility. One solution uses a unilateral surface EMG (sEMG) interface on the temporalis muscle to provide autonomous control of a powered wheelchair. Limbitless Journey, an EMG-controlled serious game, intends to provide users with a virtual environment to train in before use in a real-world scenario. A recent study analyzed the effect of video game training on the use of sEMG systems on the forearm, showing significant improvement in the usage of the interface but no difference between Free Play and structured play. The study …

Integrating Therapy Into Play: Stand-On Ride-On For A Child With Cerebral Palsy, Kira Flanagan

UNF Graduate Theses and Dissertations

This study focuses on the development of an adaptive ride-on toy specifically designed for a 2.5-year-old child with spastic diplegic cerebral palsy. As a feasibility study, the primary objective of this innovative device is to enhance motor function, foster autonomy, and improve the overall quality of life for the child. The Power Mobility Device (PMD) integrates actuation and steering modifications, and a harness mechanism tailored to meet the child's unique needs. Comprehensive assessments of the child's spatiotemporal gait characteristics were conducted before and after a three-month usage period. The results reveal significant improvements in the child's ability to control dynamic …

การพัฒนาแผ่นปิดแผลที่มีโปรตีนกาวไหมและสารสกัดจากอบเชยสำหรับแผลติดเชื้อ, สิริพร ปิยะพันธ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

โปรตีนกาวไหม (Silk sericin) เป็นโปรตีนจากธรรมชาติ ซึ่งเป็นวัสดุเหลือทิ้งจากการสกัดรังไหมเอาเส้นใยไหม (Silk fibroin) ไปใช้ โปรตีนกาวไหมถูกนำมาใช้ประโยชน์อย่างแพร่หลายในงานทางการแพทย์ ไม่ว่าจะเป็นงานด้านการนำส่งยา สเต็มเซลล์ การสร้างเนื่อเยื่อใหม่ แผ่นปิดแผล ในรูปแบบของ แผ่นฟิล์ม (film) ไฮโดรเจล (hydrogel) โครงเลี้ยงเซลล์ (scaffold) หรืออนุภาคระดับไมโคร/นาโน เป็นต้น ในงานวิจัยชิ้นนี้ผู้วิจัยมีความสนใจที่นำโปรตีนกาวไหมมาขึ้นรูปเป็นแผ่นปิดแผล ร่วมกับการใช้พอลิไวนิลแอลกอฮอล์และกลีเซอรีน ด้วยการเชื่อมขวาง 2 รูปแบบ คือ การเชื่อมขวางทางกายภาพโดยกระบวนการ freeze-thaw และการเชื่อมขวางทางเคมีด้วยสารเชื่อมขวางกลูตาราลดีไฮด์ (glutaraldehyde) และทำการศึกษาคุณสมบัติต่างๆ จากการศึกษา พบว่า แผ่นปิดแผลที่ขึ้นรูปได้ทั้ง 2 แบบ มีรูพรุนกระจายอยู่ทั่วทั้งแผ่น โครงสร้างภายในจับกันเป็นโครงข่ายได้เป็นอย่างดี ผลการวิเคราะห์หมู่ฟังก์ชัน ปรากฎว่า พบหมู่ amide I ที่ 1618-1640 cm-1 (C=O stretching) หมู่ amide II ที่ 1518-1638 cm-1 (N-H bending and C-N stretching) และ หมู่ amide III ที่ 1238 cm-1 (C-N and C=O stretching) จากแผ่นปิดแผลทุกชนิด โดยในแผ่นปิดแผลที่ใช้สารเชื่อมขวางกลูตาราลดีไฮด์จะพบ peak ที่2830 -3000 cm-1 ซึ่งแสดงถึงพันธะ C-H ของหมู่อัลดีไฮด์กับหมู่แอลคิล การทดสอบสมบัติเชิงกล (mechanical property) แสดงให้เห็นว่า การเชื่อมขวางทั้ง 2 วิธี ทำให้ค่ามอดูลัสของยัง (Young’s modulus) เพิ่มขึ้น แผ่นปิดแผลสามารถทนต่อการเปลี่ยนแปลงรูปร่างได้มากขึ้น และการเชื่อมขวางทางกายภาพยังทำให้ระยะยืดที่จุดขาด (elongation at break) ของแผ่นปิดแผลสูงขึ้น แต่ในขณะเดียวระยะยืดที่จุดขาด (elongation …

การพัฒนาเท้าเทียมที่สามารถปรับ Roll-Over Shape สำหรับผู้พิการที่มีกิจวัตรประจำวันระดับต่ำถึงปานกลาง, ณิชนันทน์ ปิดทอง

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้เสนอการออกแบบเท้าเทียมแบบใหม่ที่สามารถปรับ Roll-over shape ได้สำหรับผู้พิการที่มีระดับกิจกรรมต่ำถึงปานกลาง เนื่องจากเท้าเทียมสำหรับผู้พิการที่ได้รับสิทธิเบิกจ่ายจากรัฐบาลจะเป็นเท้าเทียม SACH ซึ่งมีข้อจำกัดคือลักษณะฝ่าเท้าที่มีความแข็งและไม่สามารถงอข้อเท้าได้ จึงเป็นเหตุให้ผู้พิการมีลักษณะการเดินที่ไม่สมมาตร โดยเท้าเทียมวิจัยนี้จะสามารถปรับ Roll-over shape ตามความสูงของแต่ละบุคคล เพื่อพัฒนาความสมมาตรในการเดินให้ดีขึ้น การออกแบบเท้าเทียมจะคำนึงถึงปัจจัยต่างๆ เช่น ความยาวเท้า น้ำหนัก และส่วนสูง ซึ่งส่วนสูงเป็นปัจจัยสำคัญที่ส่งผลต่อ Roll-over shape ดังนั้นเท้าเทียมจึงได้รับการพัฒนาให้สามารถปรับ Roll-over shape ได้เพื่อรองรับผู้พิการที่มีส่วนสูงที่แตกต่างกัน การทดสอบความแข็งแรงและ Roll-over radius ทำโดยวิธีการวิเคราะห์ไฟไนต์เอลิเมนต์ด้วยโปรแกรม ANSYS 2021R2 และมีการทดสอบการเดินกับผู้พิการจริงแบบ Single Pilot Study เพื่อทดสอบประสิทธิภาพของเท้าเทียมวิจัยกับความสมมาตรของการเดิน เท้าเทียมวิจัยนี้ถูกออกแบบให้สามารถปรับ Roll-over radius ได้ 289 297 และ 323 มม. ตามลำดับ และจากการทดสอบการเดินกับผู้พิการพบว่าดัชนีสมมาตรจะเพิ่มขึ้นเมื่อปรับเท้าเทียมให้มี Roll-over radius ที่มากขึ้น โดยมีค่าดัชนีความสมมาตรของ Roll-over radius 289 297 323 มม. และเท้า SACH คือ 0.03%, -0.77%, -7.12% และ -11.62% ตามลำดับ และค่าดัชนีความสมมาตรของ Step time สำหรับเท้าเทียมที่มี Roll-over radius 289 297 และ 323 มม. และเท้า SACH คือ -4.14%, -11.07%, -18.19% และ -21.30% ตามลำดับ และจากการทดสอบกับผู้พิการจริงพบว่าดัชนีความสมมาตรของเท้าเทียมที่มี Roll-over radius 289 มม. ดีกว่าเท้า SACH ในแง่ของ Roll-over radius และ Step time 99.7% …

Evaluation Of Silk Fibroin And Hylauronic Acid As Otic Drug Delivery System Additives; Investigation Of Silk Fibroins Responses To Enviromental Stimulii, Kolton Charles Sandau

Graduate Student Theses, Dissertations, & Professional Papers

The Serban lab has previously developed and reported on a single application drug delivery system for the treatment of otitis externa. Otitis externa also known as outer ear infections is a very common ailment that impacts large portions of both human and domestic animal populations. Typical treatment for otitis externa typically requires an extended dosing regimen over several days that is inconvenient and can lead to poor clinical outcomes due to poor patient compliance. Our delivery system employs a thixotropic gel to deliver a steady dose of medication over the duration of the infection.

Here we evaluated the reproducibility and …

Development Of Porous Poly(Methylmethacrylate) Beads For Toxic Cytokine Removal Application, Nutchanon Putthabucha

Chulalongkorn University Theses and Dissertations (Chula ETD)

Sepsis is a vital cause of death globally, primarily due to the uncontrolled secretion of cytokines that disrupt homeostasis. Hemoperfusion is an extracorporeal blood purification technique to treat sepsis that is uncomplicated and effective. The adsorbent material is the essence part of this technique. Since it has to direct contact with blood, the material requires necessary properties, including hemocompatibility, biocompatibility, mechanical stability, etc. Here in this thesis, we developed a new adsorbent material for hemoperfusion using PMMA beads suspension polymerization. Five different porogens, including ethyl acetate, tributyrin (short-chain triglycerides), MCT oil (medium-chain triglyceride), soybean oil (long-chain triglyceride), and toluene were …