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Stochastic Modeling Of Neuronal Transport In Various Cellular Geometries, Abhishek Choudhary Mr., Peter Kramer 2019 Rensselaer Polytechnic Institute

Stochastic Modeling Of Neuronal Transport In Various Cellular Geometries, Abhishek Choudhary Mr., Peter Kramer

Biology and Medicine Through Mathematics Conference

No abstract provided.


Assessing The Potential Impact Of Nanotechnology On The Purification Of Water, Noor Khan 2019 Collin College

Assessing The Potential Impact Of Nanotechnology On The Purification Of Water, Noor Khan

Quest

Independent Research Paper

Research in progress for PHYS 2426: University Physics II

Faculty Mentor: Raji Kannampuzha, Ph.D.

The following paper represents research work done by students in a University Physics 2426 class, the second half of a two-semester introductory course in physics. It is a calculus-based physics course, intended primarily for physics, chemistry, math, and engineering majors. Students are introduced to the concept of academic research by learning to ask research-focused questions and then use the library resources to pursue outside research to find answers. For this assignment, students are asked to investigate a physical science, biological science, or ...


Aptamers For Diagnostics With Applications For Infectious Diseases, Muslum Ilgu, Rezzan Fazlioglu, Meric Ozturk, Yasemin Ozsurekci, Marit Nilsen-Hamilton 2019 Middle East Technical University

Aptamers For Diagnostics With Applications For Infectious Diseases, Muslum Ilgu, Rezzan Fazlioglu, Meric Ozturk, Yasemin Ozsurekci, Marit Nilsen-Hamilton

Biochemistry, Biophysics and Molecular Biology Publications

Aptamers are in vitro selected oligonucleotides (DNA, RNA, oligos with modified nucleotides) that can have high affinity and specificity for a broad range of potential targets with high affinity and specificity. Here we focus on their applications as biosensors in the diagnostic field, although they can also be used as therapeutic agents. A small number of peptide aptamers have also been identified. In analytical settings, aptamers have the potential to extend the limit of current techniques as they offer many advantages over antibodies and can be used for real-time biomarker detection, cancer clinical testing, and detection of infectious microorganisms and ...


An Automated Bayesian Pipeline For Rapid Analysis Of Single-Molecule Binding Data, Carlas Smith, Karina Jouravleva, Maximiliaan Huisman, Samson M. Jolly, Phillip D. Zamore, David Grünwald 2019 University of Massachusetts Medical School

An Automated Bayesian Pipeline For Rapid Analysis Of Single-Molecule Binding Data, Carlas Smith, Karina Jouravleva, Maximiliaan Huisman, Samson M. Jolly, Phillip D. Zamore, David Grünwald

David Grünwald

Single-molecule binding assays enable the study of how molecular machines assemble and function. Current algorithms can identify and locate individual molecules, but require tedious manual validation of each spot. Moreover, no solution for high-throughput analysis of single-molecule binding data exists. Here, we describe an automated pipeline to analyze single-molecule data over a wide range of experimental conditions. In addition, our method enables state estimation on multivariate Gaussian signals. We validate our approach using simulated data, and benchmark the pipeline by measuring the binding properties of the well-studied, DNA-guided DNA endonuclease, TtAgo, an Argonaute protein from the Eubacterium Thermus thermophilus. We ...


Bisthioether Stapled Peptides Targeting Polycomb Repressive Complex 2 Gene Repression, Gan Zhang 2019 The Graduate Center, City University of New York

Bisthioether Stapled Peptides Targeting Polycomb Repressive Complex 2 Gene Repression, Gan Zhang

All Dissertations, Theses, and Capstone Projects

Interactions between proteins play a key role in nearly all cellular process, and therefore, disruption of such interactions may lead to many different types of cellular dysfunctions. Hence, pathologic protein-protein interactions (PPIs) constitute highly attractive drug targets and hold great potential for developing novel therapeutic agents for the treatment of incurable human diseases. Unfortunately, the identification of PPI inhibitors is an extremely challenging task, since traditionally used small molecule ligands are mostly unable to cover and anchor on the extensive flat surfaces that define those binary protein complexes. In contrast, large biomolecules such as proteins or peptides are ideal fits ...


Analyzing Neuronal Dendritic Trees With Convolutional Neural Networks, Olivier Trottier, Jonathon Howard 2019 Yale University

Analyzing Neuronal Dendritic Trees With Convolutional Neural Networks, Olivier Trottier, Jonathon Howard

Yale Day of Data

In the biological sciences, image analysis software are used to detect, segment or classify a variety of features encountered in living matter. However, the algorithms that accomplish these tasks are often designed for a specific dataset, making them hardly portable to accomplish the same tasks on images of different biological structures. Recently, convolutional neural networks have been used to perform complex image analysis on a multitude of datasets. While applications of these networks abound in the technology industry and computer science, use cases are not as common in the academic sciences. Motivated by the generalizability of neural networks, we aim ...


A Three State Model Can Explain The Dynamics Of Class Iv Drosophila Dendritic Tips, Sabyasachi Sutradhar 2019 Yale University

A Three State Model Can Explain The Dynamics Of Class Iv Drosophila Dendritic Tips, Sabyasachi Sutradhar

Yale Day of Data

No abstract provided.


An Automated Bayesian Pipeline For Rapid Analysis Of Single-Molecule Binding Data, Carlas Smith, Karina Jouravleva, Maximiliaan Huisman, Samson M. Jolly, Phillip D. Zamore, David Grünwald 2019 University of Massachusetts Medical School

An Automated Bayesian Pipeline For Rapid Analysis Of Single-Molecule Binding Data, Carlas Smith, Karina Jouravleva, Maximiliaan Huisman, Samson M. Jolly, Phillip D. Zamore, David Grünwald

Open Access Articles

Single-molecule binding assays enable the study of how molecular machines assemble and function. Current algorithms can identify and locate individual molecules, but require tedious manual validation of each spot. Moreover, no solution for high-throughput analysis of single-molecule binding data exists. Here, we describe an automated pipeline to analyze single-molecule data over a wide range of experimental conditions. In addition, our method enables state estimation on multivariate Gaussian signals. We validate our approach using simulated data, and benchmark the pipeline by measuring the binding properties of the well-studied, DNA-guided DNA endonuclease, TtAgo, an Argonaute protein from the Eubacterium Thermus thermophilus. We ...


Effects Of H-Ras Disease Mutations On Binding To The Ras Binding Domain Of Pi3ky Measured By Micro-Scale Thermophoresis, Justin Martyr 2019 University of Colorado, Boulder

Effects Of H-Ras Disease Mutations On Binding To The Ras Binding Domain Of Pi3ky Measured By Micro-Scale Thermophoresis, Justin Martyr

Undergraduate Honors Theses

H-Ras is a G-protein responsible for the activation of multiple signaling pathways that control cell growth. Our primary interest is examining its role in the regulation of the phosphoinositide-3-kinase (PI3K) signaling cascade, as H-Ras has been previously shown to recruit PI3K to the plasma membrane where this lipid kinase phosphorylates PIP2 to PIP3, a signal for cellular growth. The H-Ras-PI3K-PIP3 signaling pathway is known to be highly oncogenic, with constitutive activation of H-Ras leading to increased PIP3 production and cell growth. We hypothesize that disease-linked mutations on the binding interface between Ras and PI3K increase the ...


Membrane Protein Nanoparticles: The Shape Of Things To Come, Kailene S. Simon, Naomi L. Pollock, Sarah C. Lee 2018 University of Massachusetts Medical School

Membrane Protein Nanoparticles: The Shape Of Things To Come, Kailene S. Simon, Naomi L. Pollock, Sarah C. Lee

Open Access Articles

The use of styrene-maleic acid (SMA) for the purification of a wide range of membrane proteins (MPs) from both prokaryotic and eukaryotic sources has begun to make an impact in the field of MP biology. This method is growing in popularity as a means to purify and thoroughly investigate the structure and function of MPs and biological membranes. The amphiphilic SMA copolymer can effectively extract MPs directly from a native lipid bilayer to form discs approximately 10 nm in diameter. The resulting lipid particles, or styrene-maleic acid lipid particles (SMALPs), contain SMA, protein and membrane lipid. MPs purified in SMALPs ...


Investigation Of Flow Disturbances And Multi-Directional Wall Shear Stress In The Stenosed Carotid Artery Bifurcation Using Particle Image Velocimetry, Amanda L. DiCarlo 2018 The University of Western Ontario

Investigation Of Flow Disturbances And Multi-Directional Wall Shear Stress In The Stenosed Carotid Artery Bifurcation Using Particle Image Velocimetry, Amanda L. Dicarlo

Electronic Thesis and Dissertation Repository

Hemodynamics and shear forces are associated with pathological changes in the vascular wall and its function, resulting in the focal development of atherosclerosis. Flow complexities that develop in the presence of established plaques create environments favourable to thrombosis formation and potentially plaque rupture leading to stroke. The carotid artery bifurcation is a common site of atherosclerosis development. Recently, the multi-directional nature of shear stress acting on the endothelial layer has been highlighted as a risk factor for atherogenesis, emphasizing the need for accurate measurements of shear stress magnitude as well direction. In the absence of comprehensive patient specific datasets numerical ...


Optimization Of Detergent-Mediated Reconstitution Of Influenza A M2 Protein Into Proteoliposomes, Catherine Hirshfeld Crouch, Margaret H. Bost , '17, Tae H. Kim , '14, Bryan M. Green , '16, Douglas Stuart Arbuckle , '17, Carl H. Grossman, Kathleen P. Howard 2018 Swarthmore College

Optimization Of Detergent-Mediated Reconstitution Of Influenza A M2 Protein Into Proteoliposomes, Catherine Hirshfeld Crouch, Margaret H. Bost , '17, Tae H. Kim , '14, Bryan M. Green , '16, Douglas Stuart Arbuckle , '17, Carl H. Grossman, Kathleen P. Howard

Physics & Astronomy Faculty Works

We report the optimization of detergent-mediated reconstitution of an integral membrane-bound protein, full-length influenza M2 protein, by direct insertion into detergent-saturated liposomes. Detergent-mediated reconstitution is an important method for preparing proteoliposomes for studying membrane proteins, and must be optimized for each combination of protein and membrane constituents used. The purpose of the reconstitution was to prepare samples for site-directed spin-labeling electron paramagnetic resonance (SDSL-EPR) studies. Our goals in optimizing the protocol were to minimize the amount of detergent used, reduce overall proteoliposome preparation time, and confirm the removal of all detergent. The liposomes were comprised of (1-palmitoyl-2-oleyl-sn-glycero-phosphocholine (POPC) and 1-palmitoyl-2-oleyl-sn-glycero-3- ...


Metformin, Oxidative Stress, And Infertility: A Way Forward, Rehana Rehman, Syed Hani Abidi, Faiza Alam 2018 Aga Khan University

Metformin, Oxidative Stress, And Infertility: A Way Forward, Rehana Rehman, Syed Hani Abidi, Faiza Alam

Department of Biological & Biomedical Sciences

No abstract provided.


Evidence For A Role Of Spindle Matrix Formation In Cell Cycle Progression By Antibody Perturbation, Changfu Yao, Chao Wang, Yeran Li, Michael Zavortink, Vincent Archambault, Jack Girton, Kristen M. Johansen, Jorgen Johansen 2018 Iowa State University

Evidence For A Role Of Spindle Matrix Formation In Cell Cycle Progression By Antibody Perturbation, Changfu Yao, Chao Wang, Yeran Li, Michael Zavortink, Vincent Archambault, Jack Girton, Kristen M. Johansen, Jorgen Johansen

Biochemistry, Biophysics and Molecular Biology Publications

In Drosophila it has recently been demonstrated that a spindle matrix in the form of a membrane-less macromolecular assembly embeds the microtubule-based spindle apparatus. In addition, two of its constituents, Megator and Chromator, were shown to function as spatial regulators of spindle checkpoint proteins. However, whether the spindle matrix plays a wider functional role in spatially regulating cell cycle progression factors was unknown. Here using a live imaging approach we provide evidence that a number of key cell cycle proteins such as Cyclin B, Polo, and Ran co-localize with the spindle matrix during mitosis. Furthermore, prevention of spindle matrix formation ...


Combined High-Speed Single Particle Tracking Of Membrane Proteins And Super-Resolution Of Membrane-Associated Structures, Hanieh Mazloom Farsibaf, Keith A. Lidke 2018 University of New Mexico

Combined High-Speed Single Particle Tracking Of Membrane Proteins And Super-Resolution Of Membrane-Associated Structures, Hanieh Mazloom Farsibaf, Keith A. Lidke

Shared Knowledge Conference

Many experiments have shown that the diffusive motion of lipids and membrane proteins are slower on the cell surface than those in artificial lipid bilayers or blebs. One hypothesis that may partially explain this mystery is the effect of the cytoskeleton structures on the protein dynamics. A model proposed by Kusumi [1] is the Fence-Picket Model which describes the cell membrane as a set of compartment regions, each ~ 10 to 200 nm in size, created by direct or indirect interaction of lipids and proteins with actin filaments just below the membrane. To test this hypothesis, we have assembled a high-speed ...


Arginine In The Farm And Sarm: A Role In Chain-Length Determination For Arginine In The Aspartate-Rich Motifs Of Isoprenyl Diphosphate Synthases From Mycobacterium Tuberculosis, Raimund Nagel, Jill A. Thomas, Faith A. Adekunle, Francis M. Mann, Reuben J. Peters 2018 Iowa State University

Arginine In The Farm And Sarm: A Role In Chain-Length Determination For Arginine In The Aspartate-Rich Motifs Of Isoprenyl Diphosphate Synthases From Mycobacterium Tuberculosis, Raimund Nagel, Jill A. Thomas, Faith A. Adekunle, Francis M. Mann, Reuben J. Peters

Biochemistry, Biophysics and Molecular Biology Publications

Isoprenyl chains are found in many important metabolites. These are derived from precursors of the appropriate length produced by isoprenyl diphosphate synthases (IDSs). The human pathogen Mycobacterium tuberculosis makes various isoprenoids/terpenoids, with important roles in their biosynthesis played by two closely related IDSs, encoded by grcC1 (Rv0562) and grcC2 (Rv0989c), with Rv0989c generating the 10-carbon precursor (E)-geranyl diphosphate (GPP), and Rv0562 the 20-carbon precursor (E,E,E)-geranylgeranyl diphosphate (GGPP). Intriguingly, while Rv0562 contains the prototypical trans-IDS first and second aspartate-rich (DDxxD) motifs (FARM and SARM, respectively), Rv0989c uniquely contains arginine in place of the second Asp in ...


Continuous Interdomain Orientation Distributions Reveal Components Of Binding Thermodynamics, Yang Qi, Jeffrey W. Martin, Adam W. Barb, Francois Thelot, Anthony Yan, Bruce R. Donald, Terrence G. Oas 2018 Duke University Medical Center

Continuous Interdomain Orientation Distributions Reveal Components Of Binding Thermodynamics, Yang Qi, Jeffrey W. Martin, Adam W. Barb, Francois Thelot, Anthony Yan, Bruce R. Donald, Terrence G. Oas

Biochemistry, Biophysics and Molecular Biology Publications

The flexibility of biological macromolecules is an important structural determinant of function. Unfortunately, the correlations between different motional modes are poorly captured by discrete ensemble representations. Here, we present new ways to both represent and visualize correlated interdomain motions. Interdomain motions are determined directly from residual dipolar couplings, represented as a continuous conformational distribution, and visualized using the disk-on-sphere representation. Using the disk-on-sphere representation, features of interdomain motions, including correlations, are intuitively visualized. The representation works especially well for multidomain systems with broad conformational distributions.This analysis also can be extended to multiple probability density modes, using a Bingham mixture ...


Accurate Flexible Refinement Of Atomic Models Against Medium-Resolution Cryo-Em Maps Using Damped Dynamics, Julio A. Kovacs, Vitold E. Galkin, Willy Wriggers 2018 Old Dominion University

Accurate Flexible Refinement Of Atomic Models Against Medium-Resolution Cryo-Em Maps Using Damped Dynamics, Julio A. Kovacs, Vitold E. Galkin, Willy Wriggers

Mechanical & Aerospace Engineering Faculty Publications

Background: Dramatic progress has recently been made in cryo-electron microscopy technologies, which now make possible the reconstruction of a growing number of biomolecular structures to near-atomic resolution. However, the need persists for fitting and refinement approaches that address those cases that require modeling assistance.

Methods: In this paper, we describe algorithms to optimize the performance of such medium-resolution refinement methods. These algorithms aim to automatically optimize the parameters that define the density shape of the flexibly fitted model, as well as the time-dependent damper cutoff distance. Atomic distance constraints can be prescribed for cases where extra containment of parts of ...


A 2′Fy-Rna Motif Defines An Aptamer For Ebolavirus Secreted Protein, Shambhavi Shubham, Jan Hoinka, Soma Banerjee, Emma Swanson, Jacob A. Dillard, Nicholas J. Lennemann, Teresa M. Przytycka, Wendy Maury, Marit Nilsen-Hamilton 2018 Iowa State University

A 2′Fy-Rna Motif Defines An Aptamer For Ebolavirus Secreted Protein, Shambhavi Shubham, Jan Hoinka, Soma Banerjee, Emma Swanson, Jacob A. Dillard, Nicholas J. Lennemann, Teresa M. Przytycka, Wendy Maury, Marit Nilsen-Hamilton

Biochemistry, Biophysics and Molecular Biology Publications

With properties such as stability to long-term storage and amenability to repetitive use, nucleic acid aptamers are compatible with many sensing/transducing platforms intended for use in remote locations. Sensors with these properties are important for quickly identifying ebolavirus outbreaks, which frequently start in locations that lack sophisticated equipment. Soluble glycoprotein (sGP), an excellent biomarker for ebolaviruses, is produced from the same gene as the ebolavirus glycoprotein GP1,2 that decorates the surface of the viral particle and is secreted in abundance into the blood stream even during the early stages of infection. Here, we report the selection and properties ...


Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler 2018 Washington University in St. Louis

Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler

Engineering and Applied Science Theses & Dissertations

The brain connects to, modulates, and receives information from every organ in the body. As such, brain-computer interfaces (BCIs) have vast potential for diagnostics, medical therapies, and even augmentation or enhancement of normal functions. BCIs provide a means to explore the furthest corners of what it means to think, to feel, and to act—to experience the world and to be who you are. This work focuses on the development of a chronic bi-directional BCI for sensorimotor restoration through the use of separable frequency bands for recording motor intent and providing sensory feedback via electrocortical stimulation. Epidural cortical surface electrodes ...


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