Isoprene and acetone concentration profiles during exercise on an ergometer

A real-time recording setup combining exhaled breath VOC measurements by proton transfer reaction mass spectrometry (PTR-MS) with hemodynamic and respiratory data is presented. Continuous automatic sampling of exhaled breath is implemented on the basis of measured respiratory flow: a flow-controlled shutter mechanism guarantees that only end-tidal exhalation segments are drawn into the mass spectrometer for analysis. Exhaled breath concentration profiles of two prototypic compounds, isoprene and acetone, during several exercise regimes were acquired, reaffirming and complementing earlier experimental findings regarding the dynamic response of these compounds reported by Senthilmohan et al. [1] and Karl et al. [2]. While isoprene tends to react very sensitively to changes in pulmonary ventilation and perfusion due to its lipophilic behavior and low Henry constant, hydrophilic acetone shows a rather stable behavior. Characteristic (median) values for breath isoprene concentration and molar flow, i.e., the amount of isoprene exhaled per minute are 100 ppb and 29 nmol/min, respectively, with some intra-individual day-to-day variation. At the onset of exercise breath isoprene concentration increases drastically, usually by a factor of ~3-4 within about one minute. Due to a simultaneous increase in ventilation, the associated rise in molar flow is even more pronounced, leading to a ratio between peak molar flow and molar flow at rest of ~11. Our setup holds great potential in capturing continuous dynamics of non-polar, low-soluble VOCs over a wide measurement range with simultaneous appraisal of decisive physiological factors affecting exhalation kinetics.Comment: 35 page

Using a human cardiovascular-respiratory model to characterize cardiac tamponade and pulsus paradoxus

<p>Abstract</p> <p>Background</p> <p>Cardiac tamponade is a condition whereby fluid accumulation in the pericardial sac surrounding the heart causes elevation and equilibration of pericardial and cardiac chamber pressures, reduced cardiac output, changes in hemodynamics, partial chamber collapse, pulsus paradoxus, and arterio-venous acid-base disparity. Our large-scale model of the human cardiovascular-respiratory system (H-CRS) is employed to study mechanisms underlying cardiac tamponade and pulsus paradoxus. The model integrates hemodynamics, whole-body gas exchange, and autonomic nervous system control to simulate pressure, volume, and blood flow.</p> <p>Methods</p> <p>We integrate a new pericardial model into our previously developed H-CRS model based on a fit to patient pressure data. Virtual experiments are designed to simulate pericardial effusion and study mechanisms of pulsus paradoxus, focusing particularly on the role of the interventricular septum. Model differential equations programmed in C are solved using a 5^th-order Runge-Kutta numerical integration scheme. MATLAB is employed for waveform analysis.</p> <p>Results</p> <p>The H-CRS model simulates hemodynamic and respiratory changes associated with tamponade clinically. Our model predicts effects of effusion-generated pericardial constraint on chamber and septal mechanics, such as altered right atrial filling, delayed leftward septal motion, and prolonged left ventricular pre-ejection period, causing atrioventricular interaction and ventricular desynchronization. We demonstrate pericardial constraint to markedly accentuate normal ventricular interactions associated with respiratory effort, which we show to be the distinct mechanisms of pulsus paradoxus, namely, series and parallel ventricular interaction. Series ventricular interaction represents respiratory variation in right ventricular stroke volume carried over to the left ventricle via the pulmonary vasculature, whereas parallel interaction (via the septum and pericardium) is a result of competition for fixed filling space. We find that simulating active septal contraction is important in modeling ventricular interaction. The model predicts increased arterio-venous CO₂due to hypoperfusion, and we explore implications of respiratory pattern in tamponade.</p> <p>Conclusion</p> <p>Our modeling study of cardiac tamponade dissects the roles played by septal motion, atrioventricular and right-left ventricular interactions, pulmonary blood pooling, and the depth of respiration. The study fully describes the physiological basis of pulsus paradoxus. Our detailed analysis provides biophysically-based insights helpful for future experimental and clinical study of cardiac tamponade and related pericardial diseases.</p

The spotted gar genome illuminates vertebrate evolution and facilitates human-teleost comparisons

To connect human biology to fish biomedical models, we sequenced the genome of spotted gar (Lepisosteus oculatus), whose lineage diverged from teleosts before teleost genome duplication (TGD). The slowly evolving gar genome has conserved in content and size many entire chromosomes from bony vertebrate ancestors. Gar bridges teleosts to tetrapods by illuminating the evolution of immunity, mineralization and development (mediated, for example, by Hox, ParaHox and microRNA genes). Numerous conserved noncoding elements (CNEs; often cis regulatory) undetectable in direct human-teleost comparisons become apparent using gar: functional studies uncovered conserved roles for such cryptic CNEs, facilitating annotation of sequences identified in human genome-wide association studies. Transcriptomic analyses showed that the sums of expression domains and expression levels for duplicated teleost genes often approximate the patterns and levels of expression for gar genes, consistent with subfunctionalization. The gar genome provides a resource for understanding evolution after genome duplication, the origin of vertebrate genomes and the function of human regulatory sequences

Impact of systemic juvenile idiopathic arthritis/Still&rsquo;s disease on adolescents as evidenced through social media posts

Renee F Modica,1 Kathleen G Lomax,2 Pamela Batzel,3 Armelle Cassanas3 1Department of Pediatrics, University of Florida, Gainesville, FL, USA; 2Immunology, Hepatology and Dermatology Medical Affairs, Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA; 3Treato, Princeton, NJ, USA Purpose: To understand the experience of adolescent systemic juvenile idiopathic arthritis (SJIA) patients and those of their parents based on their social media posts.Methods: English language posts related to SJIA, Still&rsquo;s disease, or juvenile arthritis were collected and analyzed.Results: In total, 71 posts created between 2009 and 2015 on 15 websites were identified in November 2015. Of the 32 unique authors, 17 were SJIA patients aged 13&ndash;20 years (40 posts), 7 were mothers of SJIA patients (12 posts), and 8 patients had unspecified forms of juvenile arthritis (19 posts). Many patients posted about similar diagnostic experiences marked by 5 phases: 1) early prediagnosis: pain and fatigue overlooked until crisis occurred, 2) first misdiagnosis: doctors talked about &ldquo;growing pains&rdquo; and psychosocial problems (&ldquo;fake pains&rdquo; to avoid school), 3) second misdiagnosis: severity acknowledged, but diagnosed as leukemia or another cancer, 4) tests: tests leading to diagnosis and treatment conducted, and 5) cognitive identity: patient accepted the diagnosis and its implications. Many adolescent patients, looking back at disease onset in their childhood, described themselves as a &ldquo;sleeping child&rdquo; rather than the typical active child. Several patients tried to hide their illness from friends, but expressed concerns openly online. Many patients described SJIA as a powerful external enemy, using terms like &ldquo;bulldozer,&rdquo; &ldquo;dragon,&rdquo; and &ldquo;monster.&rdquo; Many posts from patients and their mothers used superhero language/imagery to help &ldquo;fight&rdquo; SJIA. Some patients also posted about the risk of death.Conclusion: Although most adolescent SJIA patients openly posted about the difficulties of their disease online, they made efforts to hide their disease in the real world. They frequently used superhero words and images in describing their fight for better health. Physicians can use these insights when counseling SJIA patients to provide a narrative that meshes with the patients&rsquo; worldview and perhaps to improve physician&ndash;patient communication to increase treatment adherence. Keywords: adolescents, juvenile arthritis, SJIA, social media, Still&rsquo;s disease, superheroe

The family journey-to-diagnosis with systemic juvenile idiopathic arthritis: a cross-sectional study of the changing social media presence

Renee F Modica,1 Kathleen Graham Lomax,2 Pamela Batzel,3 Leah Shapardanis,3 Kimberly Compton Katzer,3 Melissa E Elder1 1Division of Pediatric Rheumatology, Immunology and Infectious Diseases, University of Florida, Gainesville, FL, USA; 2Immunology and Dermatology Medical Affairs, Novartis Pharmaceuticals Corporation, East Hanover, USA; 3Treato, Princeton, NJ, USA Background: Children with systemic juvenile idiopathic arthritis (SJIA) often encounter a delay between symptom onset and disease diagnosis, partly due to the broad differential of fever and lack of symptom recognition by providers. Families often seek multiple medical opinions and post on social media about their frustrations. This linguistic analysis observed the changing language patterns and social media posting behaviors of parents in the time leading to, during, and after SJIA diagnosis. Methods: Public social media sites were manually reviewed by a linguistic team to evaluate posts about SJIA from US-based parents. Results: A total of 3,979 posts between July 2001 and January 2015 were reviewed from 108 sites. Pre-SJIA diagnosis parents sought answers and shared status updates on social media, focusing primarily on the following three site types: alternative/natural lifestyle forums (39%), Facebook (27%), and disease-specific forums (17%). Posts during early prediagnosis phases were characterized by expressive language showing confidence in health care providers and trust in parental instincts. At later prediagnosis stages, parents continued to use social media, but the posts demonstrated increased frustration with delays in diagnosis and gaps in communication with providers. More objective symptom descriptions and a greatly reduced child-centered emotional focus were observed as parents shifted into caregiving roles. Once the diagnosis of SJIA was confirmed, parents used straightforward, less expressive language, and Facebook (47%) to make &quot;announcement&quot; posts and increased their use of SJIA websites (30%). With treatment initiation, the posts demonstrated a slow return of expressive language and an increased parental understanding of the &quot;new normal&quot;. Conclusion: Parents use different language styles, frames of reference, and websites before and after SJIA diagnosis. Gaps in parent&ndash;provider communication, especially before diagnosis, and their new roles as caregivers lead to parental use of social media to express frustration with the health care process. Providers should tailor their discussions with parents to address these issues. Keywords: systemic juvenile idiopathic arthritis, social media, linguistics, language frames, diagnostic proces

miRNA Nomenclature: A View Incorporating Genetic Origins, Biosynthetic Pathways, and Sequence Variants.

High-throughput sequencing of miRNAs has revealed the diversity and variability of mature and functional short noncoding RNAs, including their genomic origins, biogenesis pathways, sequence variability, and newly identified products such as miRNA-offset RNAs (moRs). Here we review known cases of alternative mature miRNA-like RNA fragments and propose a revised definition of miRNAs to encompass this diversity. We then review nomenclature guidelines for miRNAs and propose to extend nomenclature conventions to align with those for protein-coding genes established by international consortia. Finally, we suggest a system to encompass the full complexity of sequence variations (i.e., isomiRs) in the analysis of small RNA sequencing experiments. Trends Genet 2015 Nov; 31(11):613-26

Evolution and developmental expression of the sodium–iodide symporter (NIS, slc5a5) gene family: Implications for perchlorate toxicology

The vertebrate sodium–iodide symporter (NIS or SLC5A5) transports iodide into the thyroid follicular cells that synthesize thyroid hormone. The SLC5A protein family includes transporters of vitamins, minerals, and nutrients. Disruption of SLC5A5 function by perchlorate, a pervasive environmental contaminant, leads to human pathologies, especially hypothyroidism. Perchlorate also disrupts the sexual development of model animals, including threespine stickleback (Gasterosteus aculeatus) and zebrafish (Danio rerio), but the mechanism of action is unknown. To test the hypothesis that SLC5A5 paralogs are expressed in tissues necessary for the development of reproductive organs, and therefore are plausible candidates to mediate the effects of perchlorate on sexual development, we first investigated the evolutionary history of Slc5a paralogs to better understand potential functional trajectories of the gene family. We identified two clades of slc5a paralogs with respect to an outgroup of sodium/choline cotransporters (slc5a7); these clades are the NIS clade of sodium/iodide and lactate cotransporters (slc5a5, slc5a6, slc5a8, slc5a8, and slc5a12) and the SGLT clade of sodium/glucose cotransporters (slc5a1, slc5a2, slc5a3, slc5a4, slc5a10, and slc5a11). We also characterized expression patterns of slc5a genes during development. Stickleback embryos and early larvae expressed NIS clade genes in connective tissue, cartilage, teeth, and thyroid. Stickleback males and females expressed slc5a5 and its paralogs in gonads. Single-cell transcriptomics (scRNA-seq) on zebrafish sex-genotyped gonads revealed that NIS clade-expressing cells included germ cells (slc5a5, slc5a6a, and slc5a6b) and gonadal soma cells (slc5a8l). These results are consistent with the hypothesis that perchlorate exerts its effects on sexual development by interacting with slc5a5 or its paralogs in reproductive tissues. These findings show novel expression domains of slc5 genes in stickleback and zebrafish, which suggest similar functions across vertebrates including humans, and provide candidates to mediate the effects of perchlorate on sexual development. © 2022 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]