Medicine and Health Sciences Commons^™

Animal Models Of Non-Respiratory, Post-Acute Sequelae Of Covid-19, Abigail Vanderheiden, Michael S Diamond

2020-Current year OA Pubs

Post-acute sequelae of COVID-19 (PASC) are a diverse set of symptoms and syndromes driven by dysfunction of multiple organ systems that can persist for years and negatively impact the quality of life for millions of individuals. We currently lack specific therapeutics for patients with PASC, due in part to an incomplete understanding of its pathogenesis, especially for non-pulmonary sequelae. Here, we discuss three animal models that have been utilized to investigate PASC: non-human primates (NHPs), hamsters, and mice. We focus on neurological, gastrointestinal, and cardiovascular PASC and highlight advances in mechanistic insight that have been made using these animal models, …

Sialylated Igg Induces The Transcription Factor Rest In Alveolar Macrophages To Protect Against Lung Inflammation And Severe Influenza Disease, Saborni Chakraborty, Derek E Byers, Philip A Mudd, Michael S Diamond, Et Al.

2020-Current year OA Pubs

While most respiratory viral infections resolve with little harm to the host, severe symptoms arise when infection triggers an aberrant inflammatory response that damages lung tissue. Host regulators of virally induced lung inflammation have not been well defined. Here, we show that enrichment for sialylated, but not asialylated immunoglobulin G (IgG), predicted mild influenza disease in humans and was broadly protective against heterologous influenza viruses in a murine challenge model. Mechanistic studies show that sialylated IgG mediated this protection by inducing the transcription factor repressor element-1 silencing transcription factor (REST), which repressed nuclear factor κB (NF-κB)-driven responses, preventing severe lung …

Helminth Infections Affect Host Immune Responses To Viral Infections And Vaccines, Juan García-Bernalt Diego, Pritesh Desai, Stephen T Yeung, Payal Damani-Yokota, Kamal M Khanna, Michael S Diamond, Michael Schotsaert

2020-Current year OA Pubs

Helminths are highly prevalent in many regions of the world. Due to the chronic nature of most helminth infections, these parasites are proficient immunomodulators of their hosts. This modulation often leads to skewed or even impaired immune responses against unrelated antigens, such as viruses and vaccines, which can be both beneficial and detrimental for the host. The extent of these effects and the impact on the outcomes of viral infection depends on a variety of factors including timing and tropism of both infections, pathological mechanisms, genetic background, and environmental factors. In this review, we dissect these complex interactions between virus …

Engaging Dystonia Networks With Subthalamic Stimulation, Konstantin Butenko, Evan M Gordon, Nico U F Dosenbach, Et Al.

2020-Current year OA Pubs

Deep brain stimulation is an efficacious treatment for dystonia. While the internal pallidum serves as the primary target, recently, stimulation of the subthalamic nucleus (STN) has been investigated. However, optimal targeting within this structure and its surroundings have not been studied in depth. Indeed, historical targets that have been used for surgical treatment of dystonia are directly adjacent to the STN. Further, multiple types of dystonia exist, and outcomes are variable, suggesting that not all types would profit maximally from the same target. Therefore, a thorough investigation of neural substrates underlying stimulation effects on dystonia signs and symptoms is warranted. …

Tolerability And Long-Term Disease Control By Ighv Mutation Status Among Patients With Cll On Ibrutinib Arm Of E1912, Tait D Shanafelt, Amanda F Cashen, Et Al.

2020-Current year OA Pubs

No abstract provided.

Daily Glucocorticoids Promote Glioblastoma Growth And Circadian Synchrony To The Host, Maria F Gonzalez-Aponte, Anna R Damato, Tatiana Simon, Nigina Aripova, Fabrizio Darby, Myung Sik Jeon, Jingqin Luo, Joshua B Rubin, Erik D Herzog

2020-Current year OA Pubs

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults with a poor prognosis despite aggressive therapy. Here, we hypothesized that daily host signaling regulates tumor growth and synchronizes circadian rhythms in GBM. We find daily glucocorticoids promote or suppress GBM growth through glucocorticoid receptor (GR) signaling depending on time of day and the clock genes, Bmal1 and Cry. Blocking circadian signals, like vasoactive intestinal peptide or glucocorticoids, dramatically slows GBM growth and disease progression. Analysis of human GBM samples from The Cancer Genome Atlas (TCGA) shows that high GR expression significantly increases hazard of mortality. Finally, mouse …

Cannabis Use Characteristics And Associations With Problematic Use Outcomes, Quitting-Related Factors, And Mental Health Among Us Young Adults, Carla J Berg, Cassidy R Loparco, Katelyn F Romm, Yuxian Cui, Darcey M Mccready, Yan Wang, Y Tony Yang, Hannah S Szlyk, Erin Kasson, Rishika Chakraborty, Patricia A Cavazos-Rehg

2020-Current year OA Pubs

OBJECTIVE: Given the changes in trends of cannabis use (e.g., product types), this study examined latent classes of young adult use and associations with use-related outcomes.

METHODS: We analyzed 2023 survey data among 4,031 US young adults (M

RESULTS: LCA identified 4 classes of cannabis use frequency and types used: 'infrequent-herb/edibles' (41.4%), 'frequent-herb' (16.8%), 'moderate-herb' (28.0%), and 'moderate-oil/other' (13.8%). In multivariable analyses (referent group: 'moderate-herb' class), 'frequent-herb' reported less problematic use (B=-0.18, 95%CI=-0.30, -0.07), while 'moderate-oil/other' reported greater (B = 0.39, 95%CI = 0.27, 0.51). 'Infrequent-herb/edibles' had lower odds of driving post-use of cannabis (aOR = 0.28, 95%CI = 0.22, …

Biophysical Mapping Of Trem2-Ligand Interactions Reveals Shared Surfaces For Engagement Of Multiple Alzheimer's Disease Ligands, Jessica A Greven, Joshua R Wydra, Rory A Greer, Cynthia Zhi, David A Price, Jordyn D Svoboda, Christopher L M Camitta, Mya Washington, Daisy W Leung, Yuhua Song, Jen Alexander-Brett, Tom J Brett

2020-Current year OA Pubs

TREM2 is a signaling receptor expressed on microglia that has emerged as an important drug target for Alzheimer's disease and other neurodegenerative diseases. While a number of TREM2 ligands have been identified, little is known regarding the structural details of how they engage. To better understand this, we created a protein library of 28 different TREM2 variants that could be used to map interactions with various ligands using biolayer interferometry. The variants are located in previously identified putative binding surfaces on TREM2 called the hydrophobic site, basic site, and site 2. We found that mutations to the hydrophobic site ablated …

The Effect Of Transcutaneous Auricular Vagus Nerve Stimulation On Cardiovascular Function In Subarachnoid Hemorrhage Patients: A Randomized Trial, Gansheng Tan, Anna L Huguenard, Kara M Donovan, Phillip Demarest, Xiaoxuan Liu, Ziwei Li, Markus Adamek, Kory Lavine, Ananthv K Vellimana, Terrance T Kummer, Joshua W Osbun, Gregory J Zipfel, Peter Brunner, Eric C Leuthardt

2020-Current year OA Pubs

BACKGROUND: Subarachnoid hemorrhage (SAH) is characterized by intense central inflammation, leading to substantial post-hemorrhagic complications such as vasospasm and delayed cerebral ischemia. Given the anti-inflammatory effect of transcutaneous auricular vagus nerve stimulation (taVNS) and its ability to promote brain plasticity, taVNS has emerged as a promising therapeutic option for SAH patients. However, the effects of taVNS on cardiovascular dynamics in critically ill patients, like those with SAH, have not yet been investigated. Given the association between cardiac complications and elevated risk of poor clinical outcomes after SAH, it is essential to characterize the cardiovascular effects of taVNS to ensure this …

Cancer-Related Health Behaviors During The Covid 19 Pandemic In Geographically Diverse Samples Across The Us, Breanna B Greteman, Bettina F Drake, Kia L Davis, Et Al.

2020-Current year OA Pubs

BACKGROUND: The COVID-19 pandemic involved business closures (e.g., gyms), social distancing policies, and prolonged stressful situations that may have impacted engagement in health behaviors. Our study assessed changes in cancer-related health behaviors during the pandemic, specifically physical activity, fruit/vegetable intake, smoking/tobacco use, and alcohol consumption.

METHODS: Eight cancer centers administered mailed/web-based/telephone surveys between June 2020 and March 2021. Surveys assessed demographics, perceptions on social distancing, and self-reported changes of behaviors (less/same/more) associated with cancer prevention or risk, e.g., physical activity, fruit/vegetable intake, tobacco/smoking use, and alcohol consumption. Descriptive analyses and logistic regression models assessed association of variables with behavior change. …

Decreased Lipidated Apoe-Receptor Interactions Confer Protection Against Pathogenicity Of Apoe And Its Lipid Cargoes In Lysosomes, Jing L Guo, Alexandra Litvinchuk, David M Holtzman, Et Al.

2020-Current year OA Pubs

While apolipoprotein E (APOE) is the strongest genetic modifier for late-onset Alzheimer's disease (LOAD), the molecular mechanisms underlying isoform-dependent risk and the relevance of ApoE-associated lipids remain elusive. Here, we report that impaired low-density lipoprotein (LDL) receptor (LDLR) binding of lipidated ApoE2 (lipApoE2) avoids LDLR recycling defects observed with lipApoE3/E4 and decreases the uptake of cholesteryl esters (CEs), which are lipids linked to neurodegeneration. In human neurons, the addition of ApoE carrying polyunsaturated fatty acids (PUFAs)-CE revealed an allelic series (ApoE4 > ApoE3 > ApoE2) associated with lipofuscinosis, an age-related lysosomal pathology resulting from lipid peroxidation. Lipofuscin increased lysosomal accumulation of tau …

Leveraging A New Data Resource To Define The Response Of Cryptococcus Neoformans To Environmental Signals, Yu Sung Kang, Jeffery Jung, Holly L Brown, Chase Mateusiak, Tamara L Doering, Michael R Brent

2020-Current year OA Pubs

Cryptococcus neoformans is an opportunistic fungal pathogen with a polysaccharide capsule that becomes greatly enlarged in the mammalian host and during in vitro growth under host-like conditions. To understand how individual environmental signals affect capsule size and gene expression, we grew cells in all combinations of 5 signals implicated in capsule size and systematically measured cell and capsule sizes. We also sampled these cultures over time and performed RNA-seq in quadruplicate, yielding 881 RNA-seq samples. Analysis of the resulting data sets showed that capsule induction in tissue culture medium, typically used to represent host-like conditions, requires the presence of either …

A Sequencing Overview Of Malignant Peripheral Nerve Sheath Tumors: Findings And Implications For Treatment, Kangwen Xiao, Kuangying Yang, Angela C Hirbe

2020-Current year OA Pubs

Malignant peripheral nerve sheath tumors (MPNSTs) are rare but aggressive malignancies with a low 5-year survival rate despite current treatments. MPNSTs frequently harbor mutations in key genes such as

Commensal-Pathogen Dynamics Structure Disease Outcomes During Clostridioides Difficile Colonization, Skye R S Fishbein, Anna L Deveaux, Sakshi Khanna, Aura L Ferreiro, James Liao, Wesley Agee, Jie Ning, Bejan Mahmud, Miranda J Wallace, Tiffany Hink, Kimberly A Reske, Candice Cass, Janaki Guruge, Sidh Leekha, Sunaina Rengarajan, Erik R Dubberke, Gautam Dantas

2020-Current year OA Pubs

Gastrointestinal colonization by Clostridioides difficile is common in healthcare settings and ranges in presentation from asymptomatic carriage to lethal C. difficile infection (CDI). We used a systems biology approach to investigate why patients colonized with C. difficile have a range of clinical outcomes. Microbiota humanization of germ-free mice with fecal samples from toxigenic C. difficile carriers revealed a spectrum of virulence among clinically prevalent clade 1 lineages and identified candidate taxa, including Blautia, as markers of stable colonization. Using gnotobiotic mice engrafted with defined human microbiota, we validated strain-specific CDI severity across clade 1 strains isolated from patients. Mice engrafted …

Waste Clearance Shapes Aging Brain Health, Li-Feng Jiang-Xie, Antoine Drieu, Jonathan Kipnis

2020-Current year OA Pubs

Brain health is intimately connected to fluid flow dynamics that cleanse the brain of potentially harmful waste material. This system is regulated by vascular dynamics, the maintenance of perivascular spaces, neural activity during sleep, and lymphatic drainage in the meningeal layers. However, aging can impinge on each of these layers of regulation, leading to impaired brain cleansing and the emergence of various age-associated neurological disorders, including Alzheimer's and Parkinson's diseases. Understanding the intricacies of fluid flow regulation in the brain and how this becomes altered with age could reveal new targets and therapeutic strategies to tackle age-associated neurological decline.

Development Of A Metabolome-Based Respiratory Infection Prognostic During Covid-19 Arrival, John I Robinson, Laura R Marks, Andrew L Hinton, Jane A O'Halloran, Charles W Goss, Peter J Mucha, Jeffrey P Henderson

2020-Current year OA Pubs

In a new respiratory virus pandemic, optimizing allocation of scarce medical resources becomes an urgent challenge. Infection prognosis takes on particular importance when allocating scarce antiviral antibodies and drugs, which are most effective when administered before the onset of severe disease. During arrival of the COVID-19 pandemic to the United States in 2020, we conducted a prognostic biomarker discovery and validation effort based upon metabolomic profiling with a liquid-chromatography-mass spectrometer (LC-MS) type used clinically for rapid toxicology. We obtained urine specimens from 163 patients presenting for evaluation. We obtained LC-MS profiles in the initial cohort and used machine learning methods …

Ubr5 In Tumor Biology: Exploring Mechanisms Of Immune Regulation And Possible Therapeutic Implications In Mpnst, Diana Akinyi Odhiambo, Selina Fan, Angela C Hirbe

2020-Current year OA Pubs

Malignant peripheral nerve sheath tumor (MPNST) is a rare but aggressive soft-tissue sarcoma characterized by poor response to therapy. The primary treatment remains surgical resection with negative margins. Nonetheless, in the setting of neurofibromatosis type 1 (NF1), the five-year survival rate is at 20-50%, with recurrence occurring in up to 50% of individuals. For patients with metastatic and unresectable disease, current treatment options include cytotoxic chemotherapy, which offers minimal benefit, and most patients die within five years of diagnosis. Despite advances in targeted therapy focusing on inhibiting Ras signaling and its downstream effectors, clinical trials report minimal clinical benefit, highlighting …

Functional Performance Of Patients With Stroke During Inpatient Rehabilitation: A Cross-Sectional Study Of Home And Access Visits, Melissa J Krauss, Emily Somerville, Callista Poiter, Rebecca M Bollinger, Brianna M Holden, Gabrielle Blenden, Danielle Kretzer, Susan L Stark

2020-Current year OA Pubs

BACKGROUND: Home visits prior to inpatient rehabilitation facility (IRF) discharge allow occupational therapists to observe functional abilities among patients with stroke and address barriers that impact daily activities at home. However, home visits prior to IRF discharge are not standard practice due to barriers of time and cost constraints. We explored whether an access visit (visiting the home without the patient) could serve as an alternative to a home visit (with the patient) to anticipate functional abilities at home.

METHODS: We used baseline data from a randomized controlled trial that occurred before and during the COVID-19 pandemic, which caused predischarge …

Student And Physician Views Of How The Dobbs Decision Affects Training And Practice Location Preferences: Cross-Sectional Questionnaire Study, Morgan S Levy, Simone A Bernstein, Sarah M Mcneilly, Abigail Liberty, Shira Fishbach, Shikha Jain, Jessica A Gold, Vineet M Arora

2020-Current year OA Pubs

BACKGROUND: By allowing for abortion bans and restrictions to take effect in the majority of US states, the 2022 Dobbs v Jackson Women's Health Organization decision portends to have lasting impacts on patient care and the physician workforce. Notably, it is already beginning to impact practice location preferences of US health care workers, evidenced by declining application rates to residency programs in abortion-restrictive states since 2022. Yet, there remains a gap in the literature regarding why this trend exists.

OBJECTIVE: This study aims to describe what factors are driving the practice location preferences of medical students and physicians after the …

Analytical Performance Of Oncoprism-Hnscc, An Rna-Based Assay To Inform Immune Checkpoint Inhibitor Treatment Decisions For Recurrent/Metastatic Head And Neck Squamous Cell Carcinoma, Jeffrey Hiken, Jon Earls, Kevin C Flanagan, Rachel L Wellinghoff, Michelle Ponder, David N Messina, Jarret I Glasscock, Eric J Duncavage

2020-Current year OA Pubs

BACKGROUND: While immune checkpoint inhibitor (ICI) therapies can significantly improve outcomes for patients with recurrent/metastatic head and neck squamous cell carcinoma (RM-HNSCC), only about 15-20% benefit from such treatments. Clinical tests that guide the use of ICIs are therefore critically needed. OncoPrism-HNSCC was developed to address this need. The assay combines next generation RNA sequencing-based immunomodulatory gene expression signatures with machine learning algorithms to generate an OncoPrism score that classifies patients as having low, medium, or high likelihood of disease control in response to ICI treatment. Also, OncoPrism-HNSCC leverages the same FFPE patient tumor RNA used for ICI response prediction …

Single-Nucleus Rna Sequencing Reveals Distinct Pathophysiological Trophoblast Signatures In Spontaneous Preterm Birth Subtypes, Cherilyn Uhm, Jianlei Gu, Weina Ju, Stephanie Pizzella, Hande Oktay, Joyce Yao-Chun Peng, Sararose Guariglia, Yong Liu, Hongyu Zhao, Yong Wang, Ramkumar Menon, Nanbert Zhong

2020-Current year OA Pubs

Spontaneous preterm birth (sPTB) poses significant challenges, affecting neonatal health and neurodevelopmental outcomes worldwide. The specific effects of placental trophoblasts on the pathological development of sPTB subtypes-preterm premature rupture of fetal membranes (pPROM) and spontaneous preterm labor (sPTL)-are not fully understood, making it crucial to uncover these impacts for the development of effective therapeutic strategies. Using single-nucleus RNA sequencing, we investigated transcriptomic and cellular differences at the maternal-fetal interface in pPROM and sPTL placentas. Our findings revealed distinct trophoblast compositions with pPROM characterized predominantly by extravillous trophoblasts (EVTs), while sPTL showed an abundance of syncytiotrophoblasts (STBs). Through cell differentiation and …

Education Strategies Are The Most Commonly Used In Pediatric Rehabilitation Implementation Research: A Scoping Review, Sahar Ghahramani, Sophia C Larson, Allison J L'Hotta, Kelly M Harris, Kim Lipsey, Elvin H Geng, Lisa A Juckett, Catherine R Hoyt

2020-Current year OA Pubs

BACKGROUND: Approximately one in six children has a disability, and effective, evidence-based rehabilitation can ameliorate the impact of these conditions over the lifespan. However, implementing interventions in real-world settings remains a challenge. This scoping review aimed to summarize the characteristics, implementation strategies, and outcomes of implementation studies in pediatric rehabilitation.

METHODS: A comprehensive search was conducted in PubMed/MEDLINE, EMBASE, CINAHL, SCOPUS, and Web of Science from the database inception to December 2, 2022. Studies testing implementation strategies in pediatric rehabilitation interventions were included. Data extracted included study characteristics (e.g., country, intervention type, field of rehabilitation), implementation strategies characterized using the …

The Impact Of Covid-19 On Hiv Care: A Comprehensive Analysis Of Patient And Healthcare Providers Experiences At The Largest Hiv Treatment Center In Ghana, Peter Puplampu, Justice K Baah, Karl Osei Afoduo, Bright A Adjei, Araba Abaidoo-Myles, Victor G Davila-Roman, George B Kyei, Collins S Ahorlu

2020-Current year OA Pubs

BACKGROUND: We sought to determine how the COVID-19 pandemic affected care delivery for HIV patients in Ghana.

METHODS: Guided by the Consolidated Framework for Implementation Research (CFIR), we performed a cross-sectional study between May and July 2021 among 40 people living with HIV and 19 healthcare providers caring for HIV patients. In-depth interviews and focus group discussions were done with HIV patients, doctors, nurses, pharmacists, laboratory scientists, data scientists, administrators, and counselors to ascertain barriers and facilitators to HIV care during the pandemic. We asked for their input on removing barriers to care during this and future pandemics. Data was …

Intrinsic Adaptive Plasticity In Mouse And Human Sensory Neurons, Lisa A Mcilvried, John Smith Del Rosario, Melanie Y Pullen, Andi Wangzhou, Tayler D Sheahan, Andrew J Shepherd, Richard A Slivicki, John A Lemen, Theodore J Price, Bryan A Copits, Robert W Gereau

2020-Current year OA Pubs

In response to changes in activity induced by environmental cues, neurons in the central nervous system undergo homeostatic plasticity to sustain overall network function during abrupt changes in synaptic strengths. Homeostatic plasticity involves changes in synaptic scaling and regulation of intrinsic excitability. Increases in spontaneous firing and excitability of sensory neurons are evident in some forms of chronic pain in animal models and human patients. However, whether mechanisms of homeostatic plasticity are engaged in sensory neurons of the peripheral nervous system (PNS) is unknown. Here, we show that sustained depolarization (induced by 24-h incubation in 30 mM KCl) induces compensatory …

Label Free, Capillary-Scale Blood Flow Mapping In Vivo Reveals That Low-Intensity Focused Ultrasound Evokes Persistent Dilation In Cortical Microvasculature, Yubing Y Shen, Jyoti V Jethe, Ashlan P Reid, Jacob Hehir, Marcello Magri Amaral, Chao Ren, Senyue Hao, Chao Zhou, Jonathan A N Fisher

2020-Current year OA Pubs

Non-invasive, low intensity focused ultrasound is an emerging neuromodulation technique that offers the potential for precision, personalized therapy. An increasing body of research has identified mechanosensitive ion channels that can be modulated by FUS and support acute electrical activity in neurons. However, neuromodulatory effects that persist from hours to days have also been reported. The brain's ability to provide blood flow to electrically active regions involves a multitude of non-neuronal cell types and signaling pathways in the cerebral vasculature; an open question is whether persistent effects can be attributed, at least partly, to vascular mechanisms. Using an in vivo optical …

Opaque Ontology: Neuroimaging Classification Of Icd-10 Diagnostic Groups In The Uk Biobank, Ty Easley, Xiaoke Luo, Kayla Hannon, Petra Lenzini, Janine Bijsterbosch

2020-Current year OA Pubs

BACKGROUND: The use of machine learning to classify diagnostic cases versus controls defined based on diagnostic ontologies such as the International Classification of Diseases, Tenth Revision (ICD-10) from neuroimaging features is now commonplace across a wide range of diagnostic fields. However, transdiagnostic comparisons of such classifications are lacking. Such transdiagnostic comparisons are important to establish the specificity of classification models, set benchmarks, and assess the value of diagnostic ontologies.

RESULTS: We investigated case-control classification accuracy in 17 different ICD-10 diagnostic groups from Chapter V (mental and behavioral disorders) and Chapter VI (diseases of the nervous system) using data from the …

Buprenorphine And Postpartum Contraception Utilization Among People With Opioid Use Disorder: A Multi-State Analysis, Kevin Y Xu, Jennifer K Bello, Joanna Buss, Hendrée E Jones, Laura J Bierut, Dustin Stwalley, Hannah S Szlyk, Caitlin E Martin, Jeannie C Kelly, Ebony B Carter, Elizabeth E Krans, Richard A Grucza

2020-Current year OA Pubs

BACKGROUND: The postpartum period provides an opportunity for birthing people with opioid use disorder (OUD) to consider their future reproductive health goals. However, the relationship between the use of medication for opioid use disorder (MOUD) and contraception utilization is not well understood. We used multistate administrative claims data to compare contraception utilization rates among postpartum people with OUD initiating buprenorphine (BUP) versus no medication (psychosocial services receipt without MOUD (PSY)) in the United States (US).

METHODS: In this retrospective cohort study, we analyzed data from the Merative™ MarketScan

RESULTS: Our sample consisted of 11,118 postpartum people with OUD. Among those, …

Automated Breast Density Assessment For Full-Field Digital Mammography And Digital Breast Tomosynthesis, Shu Jiang, Debbie L Bennett, Simin Chen, Adetunji T Toriola, Graham A Colditz

2020-Current year OA Pubs

Mammographic density is a strong risk factor for breast cancer and is reported clinically as part of Breast Imaging Reporting and Data System (BI-RADS) results issued by radiologists. Automated assessment of density is needed that can be used for both full-field digital mammography (FFDM) and digital breast tomosynthesis (DBT) as both types of exams are acquired in standard clinical practice. We trained a deep learning model to automate the estimation of BI-RADS density from a prospective Washington University clinic-based cohort of 9,714 women, entering into the cohort in 2013 with follow-up through October 31, 2020. The cohort included 27% non-Hispanic …

Null Method To Estimate The Maximal Pa At Subsaturating Concentrations Of Agonist, Allison L Germann, Spencer R Pierce, Joe Henry Steinbach, Gustav Akk

2020-Current year OA Pubs

The maximal probability of being in an active state (PA,max) is a measure of gating efficacy for a given agonist acting on a given receptor channel. In macroscopic electrophysiological recordings, PA,max is typically estimated by comparing the amplitude of the current response to a saturating concentration of a test agonist to that of a reference agonist with known PA. Here, we describe an approach to estimate the PA,max for low-efficacy agonists at subsaturating concentrations. In this approach, the amplitude of the response to a high-efficacy control agonist applied alone is compared with the amplitude of the response to a control …

Distinct Properties And Activation Of Hexameric And Heptameric Pannexin 1 Channel Concatemers, Smriti Gupta, Yu-Hsin Chiu, Mohan C Manjegowda, Bimal N Desai, Kodi S Ravichandran, Douglas A Bayliss

2020-Current year OA Pubs

Pannexin 1 (PANX1) is a member of a topologically related and stoichiometrically diverse family of large pore membrane ion channels that support the flux of signaling metabolites (e.g., ATP) and fluorescent dyes. High-resolution structural analyses have identified PANX1 as a heptamer despite early evidence suggesting that it might be a hexamer. To determine if PANX1 channel activity is supported in both hexameric and heptameric conformations, we examined properties of concatenated PANX1 constructs comprising either six or seven subunits with intact or truncated C-termini (the latter to mimic caspase-cleavage activation). In whole-cell recordings from PANX1-deleted cells, the C-tail-truncated hexameric and heptameric …