Medicine and Health Sciences Commons^™

1h And 13c Nmr Assignments For (N-Methyl)-(−)-(Α)-Isosparteinium Iodide And (N-Methyl)-(−)-Sparteinium Iodide, Kavoos Kolahdouzan, O. Maduka Ogba, Daniel J. O'Leary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

(‒)-Sparteine (1) and (–)-(α)-isosparteine (2) are members of the lupine alkaloid family.^[1-2] Sparteine has found extensive use in asymmetric organic transformations, including lithiations^[3] and Pd-catalyzed oxidations.^[4-7] (α)-Isosparteine, which can be made from sparteine, has been utilized as a chiral ligand for a limited number of stereoselective reactions.^[8-9] The two compounds differ in that 1 displays an exo-endo arrangement of the bridgehead hydrogens at C-11 and C-6, respectively, while 2 retains an exo-exo arrangement of these atoms (Figure 1). This study is focused on assigning 1H chemical shifts and coupling constants and 13C chemical shifts for N-methyl …

Astromimetics: The Dawn Of A New Era For (Bio)Materials Science?, Vuk Uskoković, Victoria M. Wu

Pharmacy Faculty Articles and Research

Composite, multifunctional fine particles are likely to be at the frontier of materials science in the foreseeable future. Here we present a submicron composite particle that mimics the stratified structure of the Earth by having a zero-valent iron core, a silicate/silicide mantle, and a thin carbonaceous crust resembling the biosphere and its biotic deposits. Particles were formulated in a stable colloidal form and made to interact with various types of healthy and cancer cells in vitro. A selective anticancer activity was observed, promising from the point of view of the intended use of the particles for tumor targeting across the …

Microgel Core/Shell Architectures As Targeted Agents For Fibrinolysis, Purva Kodlekere, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We demonstrate the utility of microgel core/shell structures conjugated to fibrin-specific peptides as fibrinolytic agents. Poly(N-isopropylmethacrylamide) (pNIPMAm) based microgels conjugated to the peptide GPRPFPAC (GPRP) were observed to bring about fibrin clot erosion, merely through exploitation of the dynamic nature of the clots. These results suggest the potential utility of peptide–microgel hybrids in clot disruption and clotting modulation.

Dissecting Structure-Encoded Determinants Of Allosteric Cross-Talk Between Post-Translational Modification Sites In The Hsp90 Chaperones, Gabrielle Stetz, Amanda Tse, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Post-translational modifications (PTMs) represent an important regulatory instrument that modulates structure, dynamics and function of proteins. The large number of PTM sites in the Hsp90 proteins that are scattered throughout different domains indicated that synchronization of multiple PTMs through a combinatorial code can be invoked as an important mechanism to orchestrate diverse chaperone functions and recognize multiple client proteins. In this study, we have combined structural and coevolutionary analysis with molecular simulations and perturbation response scanning analysis of the Hsp90 structures to characterize functional role of PTM sites in allosteric regulation. The results reveal a small group of conserved PTMs …

Ferrocenylchalcone-Uracil Conjugates: Synthesis And Cytotoxic Evaluation, Amandeep Singh, Vishu Mehra, Neda Sadeghiani, Saghar Mozaffari, Keykavous Parang, Vipan Kumar

Pharmacy Faculty Articles and Research

Huisgen’s azide-alkyne cycloaddition reaction was employed to synthesize a series of 1H-1,2,3-triazole-tethered uracil-ferrocenyl chalcone conjugates with the aim of evaluating their in vitro anti-proliferative efficacy on human leukemia (CCRF-CEM) and human breast adenocarcinoma (MDA-MB-468) cell lines. Cytotoxic evaluation studies identified a number of synthesized conjugates that inhibited the proliferation of leukemia cancer cells by ~70% after 72 h. The selected synthesized conjugates were found to be significantly less cytotoxic against normal kidney cell line (LLC-PK1) when compared with CCRF-CEM cancer cells.

Geometroneurodynamics And Neuroscience, Keun-Hang Susan Yang, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

The Orthodox Interpretation of quantum mechanics, as developed by many physicists, particularly John von Neumann, addresses the role of measurement, available choices and response of the quantum system to questions posed by an observer in specific quantum laboratory experiments. As such, it is, more consistent and clearer than other interpretations of quantum mechanics and it provides an account of the interactions of observers with the external world. However, in order to explore whether quantum mechanics plays a role in the brain, which is the primary issue, one has to examine the applicability of Hilbert space structure as a valid geometric …

Atomistic Simulations And Network-Based Modeling Of The Hsp90-Cdc37 Chaperone Binding With Cdk4 Client Protein: A Mechanism Of Chaperoning Kinase Clients By Exploiting Weak Spots Of Intrinsically Dynamic Kinase Domains, John Czemeres, Kurt Buse, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

A fundamental role of the Hsp90 and Cdc37 chaperones in mediating conformational development and activation of diverse protein kinase clients is essential in signal transduction. There has been increasing evidence that the Hsp90-Cdc37 system executes its chaperoning duties by recognizing conformational instability of kinase clients and modulating their folding landscapes. The recent cryo-electron microscopy structure of the Hsp90-Cdc37- Cdk4 kinase complex has provided a framework for dissecting regulatory principles underlying differentiation and recruitment of protein kinase clients to the chaperone machinery. In this work, we have combined atomistic simulations with protein stability and network-based rigidity decomposition analyses to characterize dynamic …

Virtual Reality As A Training Tool To Treat Physical Inactivity In Children, Adam W. Kiefer, David Pincus, Michael J. Richardson, Gregory D. Myer

Psychology Faculty Articles and Research

Lack of adequate physical activity in children is an epidemic that can result in obesity and other poor health outcomes across the lifespan. Physical activity interventions focused on motor skill competence continue to be developed, but some interventions, such as neuromuscular training (NMT), may be limited in how early they can be implemented due to dependence on the child’s level of cognitive and perceptual-motor development. Early implementation of motor-rich activities that support motor skill development in children is critical for the development of healthy levels of physical activity that carry through into adulthood. Virtual reality (VR) training may be beneficial …

A Cluster Analysis Of Challenging Behaviors In Autism Spectrum Disorder, Elizabeth Stevens, Abigail Atchison, Laura Stevens, Esther Hong, Doreen Granpeesheh, Dennis Dixon, Erik J. Linstead

Mathematics, Physics, and Computer Science Faculty Articles and Research

We apply cluster analysis to a sample of 2,116 children with Autism Spectrum Disorder in order to identify patterns of challenging behaviors observed in home and centerbased clinical settings. The largest study of this type to date, and the first to employ machine learning, our results indicate that while the presence of multiple challenging behaviors is common, in most cases a dominant behavior emerges. Furthermore, the trend is also observed when we train our cluster models on the male and female samples separately. This work provides a basis for future studies to understand the relationship of challenging behavior profiles to …

Ensemble-Based Modeling And Rigidity Decomposition Of Allosteric Interaction Networks And Communication Pathways In Cyclin-Dependent Kinases: Differentiating Kinase Clients Of The Hsp90-Cdc37 Chaperone, Gabrielle Stetz, Amanda Tse, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

The overarching goal of delineating molecular principles underlying differentiation of protein kinase clients and chaperone-based modulation of kinase activity is fundamental to understanding activity of many oncogenic kinases that require chaperoning of Hsp70 and Hsp90 systems to attain a functionally competent active form. Despite structural similarities and common activation mechanisms shared by cyclin-dependent kinase (CDK) proteins, members of this family can exhibit vastly different chaperone preferences. The molecular determinants underlying chaperone dependencies of protein kinases are not fully understood as structurally similar kinases may often elicit distinct regulatory responses to the chaperone. The regulatory divergences observed for members of CDK …

An Evaluation Of The Effects Of Intensity And Duration On Outcomes Across Treatment Domains For Children With Autism Spectrum Disorder, Erik J. Linstead, D. R. Dixon, E. Hong, C. O. Burns, Ryan French, M. N. Novack, D. Granpeesheh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Applied behavior analysis (ABA) is considered an effective treatment for individuals with autism spectrum disorder (ASD), and many researchers have further investigated factors associated with treatment outcomes. However, few studies have focused on whether treatment intensity and duration have differential influences on separate skills. The aim of the current study was to investigate how treatment intensity and duration impact learning across different treatment domains, including academic, adaptive, cognitive, executive function, language, motor, play, and social. Separate multiple linear regression analyses were used to evaluate these relationships. Participants included 1468 children with ASD, ages 18 months to 12 years old, M= …

Traceable Peo-Poly(Ester) Micelles For Breast Cancer Targeting: The Effect Of Core Structure And Targeting Peptide On Micellar Tumor Accumulation, Shyam M. Garg, Igor M. Paiva, Mohammad R. Vakili, Rania Soudy, Kate Agopsowicz, Amir H. Soleimani, Mary Hitt, Kamaljit Kaur, Afsaneh Lavasanifar

Pharmacy Faculty Articles and Research

Traceable poly(ethylene oxide)-poly(ester) micelles were developed through chemical conjugation of a near-infrared (NIR) dye to the poly(ester) end by click chemistry. This strategy was tried for micelles with poly(ε-caprolactone) (PCL) or poly(α-benzyl carboxylate-ε-caprolactone) (PBCL) cores. The surface of both micelles was also modified with the breast cancer targeting peptide, P18-4. The results showed the positive contribution of PBCL over PCL core on micellar thermodynamic and kinetic stability as well as accumulation in primary orthotopic MDA-MB-231 tumors within 4–96 h following intravenous administration in mice. This was in contrast to in vitro studies where better uptake of PEO-PCL versus PEO-PBCL micelles …

Cellular And Molecular Targets Of Menthol Actions, Murat Oz, Eslam El Nebrisi, Keun-Hang Susan Yang, Frank Christopher Howarth, Lina T. Al Kury

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol belongs to monoterpene class of a structurally diverse group of phytochemicals found in plant-derived essential oils. Menthol is widely used in pharmaceuticals, confectionary, oral hygiene products, pesticides, cosmetics, and as a flavoring agent. In addition, menthol is known to have antioxidant, anti-inflammatory, and analgesic effects. Recently, there has been renewed awareness in comprehending the biological and pharmacological effects of menthol. TRP channels have been demonstrated to mediate the cooling actions ofmenthol. There has been new evidence demonstrating thatmenthol can significantly influence the functional characteristics of a number of different kinds of ligand and voltage-gated ion channels, indicating that at …

Environmental Health, Tessa Oliaro

Student Scholar Symposium Abstracts and Posters

There is a very important intersection between the environment, public health, and socioeconomic factors (Braveman, 2014). These include waste disposal, water use and quality, road safety, ecosystem services, and many more. Environmental health stresses, “the health impacts of physical, chemical, and biological agents in the environment and workplace, and learns to develop strategies to measure and control major environmental health problems both locally…and in settings around the globe” (UC Berkeley School of Public Health, 2017). This overarching umbrella can have emphases in environmental epidemiology, exposure science, climate change, ergonomics, home and industrial hygiene, and molecular epidemiology. Exploring each of these …

One Ion To Rule Them All: Combined Antibacterial, Osteoinductive And Anticancer Properties Of Selenite-Incorporated Hydroxyapatite, Vuk Uskoković, Maheshwar Adiraj Iyer, Victoria M. Wu

Pharmacy Faculty Articles and Research

Although hydroxyapatite (HAp) has been doped with dozens of different ions, the quest for an ion imparting a combination of properties conducive to bone healing is still ongoing. Because of its protean potency and the similarity in size and shape to the phosphate tetrahedron, the selenite ion presents a natural ionic substitute in HAp. The incorporation of selenite into synthetic HAp using two different methods – co-precipitation and ion-exchange sorption – was studied for its effect on crystal properties and on a triad of biological responses: antibacterial, anticancer and osteoinductive. Co-precipitation yielded HAp with a higher selenite content than sorption …

Computational Analysis Of Residue Interaction Networks And Coevolutionary Relationships In The Hsp70 Chaperones: A Community- Hopping Model Of Allosteric Regulation And Communication, Gabrielle Stetz, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Allosteric interactions in the Hsp70 proteins are linked with their regulatory mechanisms and cellular functions. Despite significant progress in structural and functional characterization of the Hsp70 proteins fundamental questions concerning modularity of the allosteric interaction networks and hierarchy of signaling pathways in the Hsp70 chaperones remained largely unexplored and poorly understood. In this work, we proposed an integrated computational strategy that combined atomistic and coarse-grained simulations with coevolutionary analysis and network modeling of the residue interactions. A novel aspect of this work is the incorporation of dynamic residue correlations and coevolutionary residue dependencies in the construction of allosteric interaction networks …

Remote Sensing Observation Of Annual Dust Cycles And Possible Causality Of Kawasaki Disease Outbreaks In Japan, Hesham El-Askary, Nick Lahaye, Erik J. Linstead, William A. Sprigg, Magdi Yacoub

Mathematics, Physics, and Computer Science Faculty Articles and Research

Kawasaki disease (KD) is a rare vascular disease that, if left untreated, can result in irreparable cardiac damage in children. While the symptoms of KD are well-known, as are best practices for treatment, the etiology of the disease and the factors contributing to KD outbreaks remain puzzling to both medical practitioners and scientists alike. Recently, a fungus known as Candida, originating in the farmlands of China, has been blamed for outbreaks in China and Japan, with the hypothesis that it can be transported over long ranges via different wind mechanisms. This paper provides evidence to understand the transport mechanisms …

Design, Synthesis, And Evaluation Of Dasatinib-Amino Acid And Dasatinib-Fatty Acid Conjugates As Protein Tyrosine Kinase Inhibitors, Rakesh Tiwari, Alex Brown, Neda Sadeghiani, Amir Nasrolahi Shirazi, Jared Bolton, Amanda Tse, Gennady M. Verkhivker, Keykavous Parang, Gongqin Sun

Pharmacy Faculty Articles and Research

Derivatives of dasatinib were synthesized via esterification with 25 carboxylic acids including amino acids and fatty acids by extending the inhibitor to interact with more diverse sites and to improve specificity. Dasatinib-L-arginine derivative (Das-R, 7) was the most potent of the inhibitors tested with IC50 values of 4.4 nM, <0.25 nM, and <0.45 nM against Csk, Src, and Abl kinases, respectively. The highest selectivity ratio obtained in our study, 91.4 Csk/Src belonged to compound 18 (Das-C10) with an IC50 of 3.2 μM for Csk compared to 35 nM for Src. Furthermore, many compounds displayed increased selectivity toward Src, as compared with Abl. Compounds 15 (Das-E) and 13 (Das-C) demonstrated the largest gains (10.2 and 10.3 Abl/Src IC50 ratios). Das-R (IC50 = 2.06 μM) was significantly more potent than Das (IC50 = 26.3 μM) against Panc-1 cells while they both showed an IC50 < 51.2 pM against BV-173 and K562 cells. Molecular modeling and binding free energy simulations revealed a good agreement with the experimental results and rationalized differences in selectivity of the studied compounds. Integration of experimental and computational approaches in the design and biochemical screening of dasatinib derivatives facilitated rational engineering and diversification of dasatinib scaffold, providing useful insights into mechanisms of kinase selectivity.

Peroxiredoxin Catalysis At Atomic Resolution, Arden Perkins, Derek Parsonage, Kimberly J. Nelson, O. Maduka Ogba, Paul Ha-Yeon Cheong, Leslie B. Poole, P. Andrew Karplus

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peroxiredoxins (Prxs) are ubiquitous cysteine-based peroxidases that guard cells against oxidative damage, are virulence factors for pathogens, and are involved in eukaryotic redox regulatory pathways. We have analyzed catalytically active crystals to capture atomic resolution snapshots of a PrxQ-subfamily enzyme (from Xanthomonas campestris) proceeding through thiolate, sulfenate, and sulfinate species. These analyses provide structures of unprecedented accuracy for seeding theoretical studies, and show novel conformational intermediates giving insight into the reaction pathway. Based on a highly non-standard geometry seen for the sulfenate intermediate, we infer that the sulfenate formation itself can strongly promote local unfolding of the active site to …

Theoretical Investigation Of Interaction Between The Set Of Ligands And Α7 Nicotinic Acetylcholine Receptor, O. E. Glukhova, Tatiana Prytkova, D. S. Shmygin

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nicotinic acetylcholine receptors (nAChRs) are neuron receptor proteins that provide a transmission of nerve impulse through the synapses. They are composed of a pentametric assembly of five homologous subunits (5 α7 subunits for α7nAChR, for example), oriented around the central pore. These receptors might be found in the chemical synapses of central and peripheral nervous system, and also in the neuromuscular synapses. Transmembrane domain of the one of such receptors constitutes ion channel. The conductive properties of ion channel strongly depend on the receptor conformation changes in the response of binding with some molecule, f.e. acetylcholine. Investigation of interaction between …

Development And Validation Of A Sensitive Uplc-Ms/Ms Method For The Quantitation Of [13c]Sucrose In Rat Plasma, Blood, And Brain: Its Application To The Measurement Of Blood-Brain Barrier Permeability, Mohammad K. Miah, Ulrich Bickel, Reza Mehvar

Pharmacy Faculty Articles and Research

Accurate and reproducible measurement of blood-brain barrier (BBB) integrity is critical in the assessment of the pathophysiology of the central nervous system disorders and in monitoring therapeutic effects. The widely-used low molecular weight marker [14C]sucrose is non-specific in the absence of chromatographic separation. The purpose of this study was to develop and validate a sensitive and reproducible LC-MS/MS method for the analysis of stable isotopemodified [13C12]sucrose in brain, plasma, and blood to determine BBB permeability to sucrose. After addition of internal standard (IS, [13C6]sucrose), the marker and IS were recovered from diluted rat blood, plasma, and brain homogenate by protein …

The Impact Of Information Technology On Patient Engagement And Health Behavior Change: A Systematic Review Of The Literature, Suhila Sawesi, Mohamed Rashrash, Kanitha Phalakornkule, Janet S. Carpenter, Josette F. Jones

Pharmacy Faculty Articles and Research

Background: Advancements in information technology (IT) and its increasingly ubiquitous nature expand the ability to engage patients in the health care process and motivate health behavior change.

Objective: Our aim was to systematically review the (1) impact of IT platforms used to promote patients’ engagement and to effect change in health behaviors and health outcomes, (2) behavior theories or models applied as bases for developing these interventions and their impact on health outcomes, (3) different ways of measuring health outcomes, (4) usability, feasibility, and acceptability of these technologies among patients, and (5) challenges and research directions for implementing …

Proper Orthogonal Decomposition Methods For The Analysis Of Real-Time Data: Exploring Peak Clustering In A Secondhand Smoke Exposure Intervention, Vincent Berardi, R. Carretero-González, N. E. Klepeis, A. Palacios, J. Belletierre, S. Hughes, S. Obayashi, M. F. Hovell

Psychology Faculty Articles and Research

This work explores a method for classifying peaks appearing within a data-intensive time-series. We summarize a case study from a clinical trial aimed at reducing secondhand smoke exposure via the installation of air particle monitors in households. Proper orthogonal decomposition (POD) in conjunction with a k-means clustering algorithm assigns each data peak to one of two clusters. Aversive feedback from the monitors increased the proportion of short-duration, attenuated peaks from 38.8% to 96.6%. For each cluster, a distribution of parameters from a physics-based model of airborne particles is estimated. Peaks generated from these distributions are correctly identified by POD/clustering …

Rapid Label-Free Detection Of E. Coli Using Antimicrobial Peptide Assisted Impedance Spectroscopy, Keren Jieng, Hashem Etayash, Sarfuddin Azmi, Selvaraj Naicker, Mahtab Hassanpourfard, Parmiss Mojir Shaibani, Garima Thakur, Kamaljit Kaur, Thomas Thundat

Pharmacy Faculty Articles and Research

There is an increasing demand for rapid detection of waterborne pathogens to monitor drinking water safety. We demonstrate a compact, label-free sensor array for rapid detection of Escherichia coli (E. coli) in contaminated water samples using antimicrobial peptide assisted impedimetric sensor platform. Interdigitated electrode arrays immobilized with the antimicrobial peptide Colicin V (ColV) were used to screen the affinity towards different bacterial strains by monitoring impedance variations in real-time. This ColV assisted impedance biosensor exhibited high selectivity towards Gram-negative strains particularly towards E. coli strains. This selective detection of E. coli from other strains was observed at 10 …

Electrochemical Characterization Of Protein Adsorption Onto Yngrt-Au And Vlgxe-Au Surfaces, Hanna Trzeciakiewicz, Jose Esteves-Villanueva, Rania Soudy, Kamaljit Kaur, Sanela Martic-Milne

Pharmacy Faculty Articles and Research

The adsorption of the proteins CD13, mucin and bovine serum albumin on VLGXE-Au and YNGRT-Au interfaces was monitored by electrochemical impedance spectroscopy in the presence of [Fe(CN)6]3−/4−. The hydrophobicity of the Au surface was tailored using specific peptides, blocking agents and diluents. The combination of blocking agents (ethanolamine or n-butylamine) and diluents (hexanethiol or 2-mercaptoethanol) was used to prepare various peptide-modified Au surfaces. Protein adsorption onto the peptide-Au surfaces modified with the combination of n-butylamine and hexanethiol produced a dramatic decrease in the charge transfer resistance, Rct, for all three proteins. In contrast, polar peptide-surfaces induced a minimal change in …

Choice Of Human–Computer Interaction Mode In Stroke Rehabilitation, Hossein Mousavi Hondori, Maryam Khademi, Lucy Dodakian, Alison Mackenzie, Cristina V. Lopes, Steven C. Cramer

Physical Therapy Faculty Articles and Research

Background and Objective. Advances in technology are providing new forms of human–computer interaction. The current study examined one form of human–computer interaction, augmented reality (AR), whereby subjects train in the real-world workspace with virtual objects projected by the computer. Motor performances were compared with those obtained while subjects used a traditional human–computer interaction, that is, a personal computer (PC) with a mouse. Methods. Patients used goal-directed arm movements to play AR and PC versions of the Fruit Ninja video game. The 2 versions required the same arm movements to control the game but had different cognitive demands. With …

Dimethylsulfide Gas Transfer Coefficients From Algal Blooms In The Southern Ocean, T. G. Bell, Warren J. De Bruyn, Christa A. Marandino, S. D. Miller, C. S. Law, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Air-sea dimethylsulfide (DMS) fluxes and bulk air-sea gradients were measured over the Southern Ocean in February-March 2012 during the Surface Ocean Aerosol Production (SOAP) study. The cruise encountered three distinct phytoplankton bloom regions, consisting of two blooms with moderate DMS levels, and a high biomass, dinoflagellate-dominated bloom with high seawater DMS levels (> 15 nM). Gas transfer coefficients were considerably scattered at wind speeds above 5 m s(-1). Bin averaging the data resulted in a linear relationship between wind speed and mean gas transfer velocity consistent with that previously observed. However, the wind-speed-binned gas transfer data distribution at all wind …

Peptide Arrays For Detecting Naphthenic Acids In Oil Sands Process Affected Water, Kamaljit Kaur, Subir Bhattacharjee, Rajesh G. Pillai, Sahar Ahmed, Sarfuddin Azmi

Pharmacy Faculty Articles and Research

Naphthenic acids (NAs) are water-soluble components of petroleum. The characterization and quantification of NAs by analytical methods have proved quite challenging, whilst the toxic effects of these water-soluble compounds on a variety of organisms adversely affecting reproduction and steroid production is becoming apparent. In this study, we report a fluorescence-based competitive binding method for rapid sensing of the presence of NAs using cellulosic peptide array strips as sensors. The peptide array was designed from sequences derived from the estrogen receptor (ER). Several of these peptides were able to detect the presence of NAs at low micromolar (∼5 mg L^{−1 …}

A Novel Label-Free Colorimetric Assay For Dna Concentration In Solution, Molla R. Islam, Michael J. Serpe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Optical devices were fabricated by sandwiching a “monolithic” poly(N-isopropylacrylamide-co-N-(3-aminopropyl) methacrylamide hydrochloride) (pNIPAm-co-APMAH) microgel layer between two semitransparent Au layers. These devices, referred to as etalons, exhibit characteristic multipeak reflectance spectra, and the position of the peaks in the spectra primarily depends on the distance between the Au surfaces mediated by the microgel layer thickness. Here, we show that the positively charged microgel layer can collapse in the presence of negatively charged single stranded DNA (ssDNA) due to ssDNA induced microgel crosslinking. The collapse results in a change in the etalon's optical properties, which can be used to detect target DNA …

Analysis Of Ligand Bias In Functional Studies Involving The Allosteric Modulation Of G Protein- Coupled Receptors, Frederick J. Ehlert, Michael T. Griffin

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Introduction

The affinity constants of a ligand for active and inactive states of a receptor ultimately determine its capacity to activate downstream signaling events. In this report, we describe a reverse-engineering strategy for estimating these microscopic constants.

Methods

Our approach involves analyzing responses measured downstream in the signaling pathway of a G protein-coupled receptor under conditions of allosteric modulation and reduced receptor expression or partial receptor inactivation. The analysis also yields estimates of the isomerization constant of the unoccupied receptor, the sensitivity constant of the signaling pathway, and the more empirical parameters of the receptor population including the observed affinities …