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Full-Text Articles in Engineering

The Trm2h : Detecting Protein-Protein Interactions By Engineering The Cell As A Biosensor, Elyse Shimomura, Paulina Perezalonso Aug 2013

The Trm2h : Detecting Protein-Protein Interactions By Engineering The Cell As A Biosensor, Elyse Shimomura, Paulina Perezalonso

Bioengineering Senior Theses

Protein-protein interactions regulate key cellular functions and cell signaling pathways in the body; biological systems can be disrupted by protein interactions or lack of interactions that cause cell dysfunction and can lead to disease or illness. However, studying these interactions is complex and difficult to quantify. In this project, we examine the interaction of two putative cancer biomarkers, Bax and PDCDS, using the tetracycline repressor-based mammalian two-hybrid system (trM2H). This in vivo system engineers the cell as a biosensor using methods of DNA cloning and mammalian cell transfections that easily detects and quantities the interaction of two proteins by the …


Analyzing Surface Protein Expression And Internalization, William Truong, Josergio Zaragoza Jul 2013

Analyzing Surface Protein Expression And Internalization, William Truong, Josergio Zaragoza

Bioengineering Senior Theses

G-protein coupled receptors (GPCRs) are currently the largest class of membrane receptors and are targeted by a majority of the modern drug therapeutics. In addition, they partake in many physiological and pathological processes such as inflammation, growth, and hormone responses. Most importantly, GPCRs are targets of many disease-specific pathways such as Alzheimers, hypertension, leukemia, and depression. As a result, there is an immense interest in studying GPCRs as this area provides further knowledge into the specific disease pathways and allows the discovery of novel therapeutics. In order to have a better understanding of pathways, scientists have studied GPCR activation. The …


Amperometric Detection Of Bioamines In Cancer Borealis Using Microchip Capillary Electrophoresis Integrated With Micellar Chromatography, Ajay Fernandez, Jason Howard, Christina Shuh Jun 2013

Amperometric Detection Of Bioamines In Cancer Borealis Using Microchip Capillary Electrophoresis Integrated With Micellar Chromatography, Ajay Fernandez, Jason Howard, Christina Shuh

Bioengineering Senior Theses

In order to study neuromodulation in Cancer borealis, commonly known as the Jonah crab, we designed a microchip capillary electrophoretic (CE) device with micellar electrokinetic chromatography (MEKC) to separate bioamines and detect their concentrations using amperometric detection (AD). The analysis will be used to characterize the bioamines: dopamine, octopamine, tyramine, serotonin, norepinephrine, and gammaaminobutyric acid (GABA). The device measures the concentration of bioamines in microdialysate samples taken directly from the pericardial cavity of the crab. The research on Jonah crabs will be applied to enhance our understanding of the crab neurology. Since the structure and in some instances, the function …


Microfluidic Detection Of Arsenic Contamination In Groundwater, Mary Reynolds, Kyle Perricone Jun 2013

Microfluidic Detection Of Arsenic Contamination In Groundwater, Mary Reynolds, Kyle Perricone

Bioengineering Senior Theses

The difficulty of detecting small quantities of arsenic in water currently threatens the health of millions of people worldwide, as long-term exposure to arsenic has been associated with both cancerous and noncancerous health risks. Existing technologies make it possible to very accurately quantify arsenic levels in water; however the expense, extensive training, and off-site analysis required by these methods impede wide scale use. Here, we report on research to develop an affordable and point-of-use microfluidic platform capable of detecting trace amounts of arsenic in groundwater samples. We intend this device to meet the World Health Organization's (WHO's) ASSURED criteria for …


Uniflow: A Collapsible Prostatic Stent To Treat The Symptoms Of Benign Prostatic Hyperplasia, Brett Simons, Senn Foote, Doug Yoon Jun 2013

Uniflow: A Collapsible Prostatic Stent To Treat The Symptoms Of Benign Prostatic Hyperplasia, Brett Simons, Senn Foote, Doug Yoon

Bioengineering Senior Theses

BPH is a widespread problem that currently does not have any highly effective and cheap solutions. We propose a solution involving a collapsible and durable stent for insertion in to the urethra to aid in urination by opening the urethra only when needed.


Polystyrene Microsphere And 5-Fluorouracil Release From Custom Designed Wound Dressing Films, Maryam Mobed-Miremadi, Raki Komarla Nagendra, Sujana Lakshmi Ramachandruni, Jason James Rook, Mallika Keralapura, Michel Goedert Jan 2013

Polystyrene Microsphere And 5-Fluorouracil Release From Custom Designed Wound Dressing Films, Maryam Mobed-Miremadi, Raki Komarla Nagendra, Sujana Lakshmi Ramachandruni, Jason James Rook, Mallika Keralapura, Michel Goedert

Bioengineering

Custom-designed wound dressing films of chitosan and alginate have been prepared by a casting/solvent evaporation method for hydrophobic therapeutic agent encapsulation. In this parametric study, the propylene glycol (PG) and calcium chloride (CaCl2) concentrations were varied for chitosan and alginate films, respectively. Mechanical and chemical inter-related responses under observations included thickness (th), elasticity (E), tensile strength (TS), sorption ability (S%) and kinetics of in-vitro drug release, specifically in terms of membrane time to burst (tB) and duration of release (tR). As shown by results of a one tailed t-test significance testing at the 95% confidence interval (α = …


Soft Microenvironments Promote The Early Neurogenic Differentiation But Not Self-Renewal Of Human Pluripotent Stem Cells, Albert Keung, Prashanth Asuri, Sanjay Kumar, David Schaffer Sep 2012

Soft Microenvironments Promote The Early Neurogenic Differentiation But Not Self-Renewal Of Human Pluripotent Stem Cells, Albert Keung, Prashanth Asuri, Sanjay Kumar, David Schaffer

Bioengineering

Human pluripotent stem cells (hPSCs) are of great interest in biology and medicine due to their ability to self-renew and differentiate into any adult or fetal cell type. Important efforts have identified biochemical factors, signaling pathways, and transcriptional networks that regulate hPSC biology. However, recent work investigating the effect of biophysical cues on mammalian cells and adult stem cells suggests that the mechanical properties of the microenvironment, such as stiffness, may also regulate hPSC behavior. While several studies have explored this mechanoregulation in mouse embryonic stem cells (mESCs), it has been challenging to extrapolate these findings and thereby explore their …


Directed Evolution Of Adeno-Associated Virus For Enhanced Gene Delivery And Gene Targeting In Human Pluripotent Stem Cells, Prashanth Asuri, Melissa Bartel, Tandis Vazin, Jae-Hyung Jang, Tiffany Wong, David Schaffer Nov 2011

Directed Evolution Of Adeno-Associated Virus For Enhanced Gene Delivery And Gene Targeting In Human Pluripotent Stem Cells, Prashanth Asuri, Melissa Bartel, Tandis Vazin, Jae-Hyung Jang, Tiffany Wong, David Schaffer

Bioengineering

Efficient approaches for the precise genetic engineering of human pluripotent stem cells (hPSCs) can enhance both basic and applied stem cell research. Adenoassociated virus (AAV) vectors are of particular interest for their capacity to mediate efficient gene delivery to and gene targeting in various cells. However, natural AAV serotypes offer only modest transduction of human embryonic and induced pluripotent stem cells (hESCs and hiPSCs), which limits their utility for efficiently manipulating the hPSC genome. Directed evolution is a powerful means to generate viral vectors with novel capabilities, and we have applied this approach to create a novel AAV variant with …


An Evolved Adeno-Associated Viral Variant Enhances Gene Delivery And Gene Targeting In Neural Stem Cells, Jae-Hyung Jang, James Koerber, Jung-Suk Kim, Prashanth Asuri, Tandis Vazin, Melissa Bartel, Albert Keung, Inchan Kwan, David Schaffer Jan 2011

An Evolved Adeno-Associated Viral Variant Enhances Gene Delivery And Gene Targeting In Neural Stem Cells, Jae-Hyung Jang, James Koerber, Jung-Suk Kim, Prashanth Asuri, Tandis Vazin, Melissa Bartel, Albert Keung, Inchan Kwan, David Schaffer

Bioengineering

Gene delivery to, and gene targeting in, stem cells would be a highly enabling technology for basic science and biomedical application. Adeno-associated viral (AAV) vectors have demonstrated the capacity for efficient delivery to numerous cells, but their application to stem cells has been limited by low transduction efficiency. Due to their considerable advantages, however, engineering AAV delivery systems to enhance gene delivery to stem cells may have an impact in stem cell biology and therapy. Therefore, using several diverse AAV capsid libraries—including randomly mutagenized, DNA shuffled, and random peptide insertion variants—we applied directed evolution to create a “designer” AAV vector …


Preparation And Characterization Of Protein-Nanotube Conjugates, Jonathan S. Dordick, Dhiral A. Shah, Ravindra C. Pangule, Shyam Sundhar Bale, Prashanth Asuri, Amit Joshi, Akhilesh Banerjee, David Vance, Ravi S. Kane Jan 2009

Preparation And Characterization Of Protein-Nanotube Conjugates, Jonathan S. Dordick, Dhiral A. Shah, Ravindra C. Pangule, Shyam Sundhar Bale, Prashanth Asuri, Amit Joshi, Akhilesh Banerjee, David Vance, Ravi S. Kane

Bioengineering

This chapter describes methods of immobilizing proteins on carbon nanotubes, using two different routes—physical adsorption and covalent attachment. We also provide an overview on how such conjugates can be characterized with the help of various techniques, such as Raman, Fourier transform infrared (FT-IR), circular dichroism (CD), and fluorescence spectroscopies, in addition to the standard enzyme kinetic analyses of activity and stability. Both the attachment routes—covalent and noncovalent—could be used to prepare protein conjugates that retained a significant fraction of their native structure and function; furthermore, the protein conjugates were operationally stable, reusable, and functional even under harsh denaturing conditions. These …