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Full-Text Articles in Physiology

A Multi-Isotope Approach Reveals Seasonal Variation In The Reliance On Marine Resources, Production Of Metabolic Water, And Ingestion Of Seawater By Two Species Of Coastal Passerine To Maintain Water Balance, Lucas Navarrete, Nico Lübcker, Felipe Alvarez, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karin Maldonado, Zachary D. Sharp, John P. Whiteman, Seth D. Newsome, Pablo Sabat Jan 2023

A Multi-Isotope Approach Reveals Seasonal Variation In The Reliance On Marine Resources, Production Of Metabolic Water, And Ingestion Of Seawater By Two Species Of Coastal Passerine To Maintain Water Balance, Lucas Navarrete, Nico Lübcker, Felipe Alvarez, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karin Maldonado, Zachary D. Sharp, John P. Whiteman, Seth D. Newsome, Pablo Sabat

Biological Sciences Faculty Publications

Tracing how free-ranging organisms interact with their environment to maintain water balance is a difficult topic to study for logistical and methodological reasons. We use a novel combination of triple-oxygen stable isotope analyses of water extracted from plasma (δ16O, δ17O, δ18O) and bulk tissue carbon (δ13C) and nitrogen (δ15N) isotopes of feathers and blood to estimate the proportional contribution of marine resources, seawater, and metabolic water used by two species of unique songbirds (genus Cinclodes) to maintain their water balance in a seasonal coastal environment. We …


Sound The (Smaller) Alarm: The Triphosphate Magic Spot Nucleotide Pgpp, Areej Malik, Megan A. Hept, Erin B. Purcell Jan 2023

Sound The (Smaller) Alarm: The Triphosphate Magic Spot Nucleotide Pgpp, Areej Malik, Megan A. Hept, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

It has recently become evident that the bacterial stringent response is regulated by a triphosphate alarmone (pGpp) as well as the canonical tetra- and pentaphosphate alarmones ppGpp and pppGpp [together, (p)ppGpp]. Often dismissed in the past as an artifact or degradation product, pGpp has been confirmed as a deliberate endpoint of multiple synthetic pathways utilizing GMP, (p)ppGpp, or GDP/GTP as precursors. Some early studies concluded that pGpp functionally mimics (p)ppGpp and that its biological role is to make alarmone metabolism less dependent on the guanine energy charge of the cell by allowing GMP-dependent synthesis to continue when GDP/GTP has been …


Comparison Of Spine–Pelvis Kinematics Variability During Sit-To-Stand And Stand-To-Sit In People With & Without Chronic Low Back Pain: A Vector Coding And Statistical Parametric Mapping Approach, Narges Jangjoo, Elham Alijanpour, Saeid Khodabakhsh, Seyed Sadredin Shojaedin, Roozbeh Naemi Nov 2022

Comparison Of Spine–Pelvis Kinematics Variability During Sit-To-Stand And Stand-To-Sit In People With & Without Chronic Low Back Pain: A Vector Coding And Statistical Parametric Mapping Approach, Narges Jangjoo, Elham Alijanpour, Saeid Khodabakhsh, Seyed Sadredin Shojaedin, Roozbeh Naemi

Rehabilitation Sciences Faculty Publications

There is evidence in the literature to suggest that low back pain may change spine–pelvis coordination during activities of daily living. This study aimed to compare the variability of the spine– pelvis coordination during sit-to-stand in people with and without LBP. Ten healthy individuals with a history of LBP and ten individuals without history of LBP participated in this study. Three-dimensional kinematic data of the upper trunk (UT), lower trunk (LT), lower back (LB), and pelvis segments during sit-to-stand and stand-to-sit were recorded using a multi-segmental spine and pelvis models using a motion capture system. The coordination patterns and the …


Hsp90 Inhibitors Modulate Sars-Cov-2 Spike Protein Subunit 1-Induced Human Pulmonary Microvascular Endothelial Activation And Barrier Dysfunction, Ruben Manuel Luciano Colunga Biancatelli, Pavel Solopov, Betsy W. Gregory, Yara Khodour, John D. Catravas Mar 2022

Hsp90 Inhibitors Modulate Sars-Cov-2 Spike Protein Subunit 1-Induced Human Pulmonary Microvascular Endothelial Activation And Barrier Dysfunction, Ruben Manuel Luciano Colunga Biancatelli, Pavel Solopov, Betsy W. Gregory, Yara Khodour, John D. Catravas

Bioelectrics Publications

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused more than 5 million deaths worldwide. Multiple reports indicate that the endothelium is involved during SARS-Cov-2-related disease (COVID-19). Indeed, COVID-19 patients display increased thrombophilia with arterial and venous embolism and lung microcapillary thrombotic disease as major determinants of deaths. The pathophysiology of endothelial dysfunction in COVID-19 is not completely understood. We have investigated the role of subunit 1 of the SARS-CoV-2 spike protein (S1SP) in eliciting endothelial barrier dysfunction, characterized dose and time relationships, and tested the hypothesis that heat shock protein 90 (HSP90) inhibitors would prevent and repair such injury. S1SP …


Pulmonary Capillary Recruitment And Distention In Mammalian Lungs: Species Similarities, David Langleben, Benjamin D. Fox, Stylianos E. Orfanos, Michele Giovinazzo, John D. Catravas Jan 2022

Pulmonary Capillary Recruitment And Distention In Mammalian Lungs: Species Similarities, David Langleben, Benjamin D. Fox, Stylianos E. Orfanos, Michele Giovinazzo, John D. Catravas

Bioelectrics Publications

Pulmonary arterial pressure rises minimally during exercise. The pulmonary microcirculation accommodates increasing blood flow via recruitment of pulmonary capillaries and, at higher flows, by distention of already perfused capillaries. The flow transition range between recruitment and distention has not been studied or compared across mammalian species, including humans. We hypothesised that the range would be similar. Functional pulmonary capillary surface area (FCSA) can be estimated using validated metabolic techniques. We reviewed data from previous studies in three mammalian species (perfused rabbit lungs and dog lung lobes, and exercising humans) and generated blood flow-FCSA curves over a range of flows. We …


Toxic Effects Of Silver Ions On Early Developing Zebrafish Embryos Distinguished From Silver Nanoparticles, Martha S. Johnson, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu Jan 2022

Toxic Effects Of Silver Ions On Early Developing Zebrafish Embryos Distinguished From Silver Nanoparticles, Martha S. Johnson, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Currently, effects of nanomaterials and their ions, such as silver nanoparticles (Ag NPs) and silver ions (Ag+), on living organisms are not yet fully understood. One of the vital questions is whether nanomaterials have distinctive effects on living organisms from any other conventional chemicals (e.g., their ions), owing to their unique physicochemical properties. Due to various experimental protocols, studies of this crucial question have been inconclusive, which hinders rational design of effective regulatory guidelines for safely handling NPs. In this study, we chronically exposed early developing zebrafish embryos (cleavage-stage, 2 hours post-fertilization, hpf) to a dilution series of …


Polar Bear Behavior: Morphologic And Physiologic Adaptations, John P. Whiteman Jan 2021

Polar Bear Behavior: Morphologic And Physiologic Adaptations, John P. Whiteman

Biological Sciences Faculty Publications

Polar bears possess morphologic and physiologic characteristics that reflect their terrestrial lineage as members of the bear family (Ursidae) as well as adaptations to the Arctic marine environment. Among marine mammals, they are the least adapted for aquatic life. They exhibit substantial seasonality in body mass, body condition, and many physiological functions, reflecting the annual cycle of both their Arctic sea ice habitat and the availability of their main prey, ringed seals. This hypercarnivorous diet has likely influenced the polar bear’s craniodental morphology and nutritional physiology. Similar to other marine mammal predators, polar bears exhibit a relatively high resting metabolic …


Triple Oxygen Isotope Measurements (Δ'17O) Of Body Water Reflect Water Intake, Metabolism, And Δ18O Of Ingested Water In Passerines, Pablo Sabat, Seth D. Newsome, Stephanie Pinochet, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karen Maldonado, Alexander R. Gerson, Zachary D. Sharp, John P. Whiteman Jan 2021

Triple Oxygen Isotope Measurements (Δ'17O) Of Body Water Reflect Water Intake, Metabolism, And Δ18O Of Ingested Water In Passerines, Pablo Sabat, Seth D. Newsome, Stephanie Pinochet, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karen Maldonado, Alexander R. Gerson, Zachary D. Sharp, John P. Whiteman

Biological Sciences Faculty Publications

Understanding physiological traits and ecological conditions that influence a species reliance on metabolic water is critical to creating accurate physiological models that can assess their ability to adapt to environmental perturbations (e.g., drought) that impact water availability. However, relatively few studies have examined variation in the sources of water animals use to maintain water balance, and even fewer have focused on the role of metabolic water. A key reason is methodological limitations. Here, we applied a new method that measures the triple oxygen isotopic composition of a single blood sample to estimate the contribution of metabolic water to the body …


Can The Carbon And Nitrogen Isotope Values Of Offspring Be Used As A Proxy For Their Mother's Diet? Using Foetal Physiology To Interpret Bulk Tissue And Amino Acid Δ15N Values, Nico Lübcker, John P. Whiteman, Seth D. Newsome, Robert P. Millar, P.J. Nico De Bruyn Jan 2020

Can The Carbon And Nitrogen Isotope Values Of Offspring Be Used As A Proxy For Their Mother's Diet? Using Foetal Physiology To Interpret Bulk Tissue And Amino Acid Δ15N Values, Nico Lübcker, John P. Whiteman, Seth D. Newsome, Robert P. Millar, P.J. Nico De Bruyn

Biological Sciences Faculty Publications

The measurement of bulk tissue nitrogen (δ15N) and carbon isotope values (δ13C) chronologically along biologically inert tissues sampled from offspring can provide a longitudinal record of their mothers' foraging habits. This study tested the important assumption that mother-offspring stable isotope values are positively and linearly correlated. In addition, any change in the mother-offspring bulk tissues and individual amino acids that occurred during gestation was investigated. Whiskers sampled from southern elephant seal pups (Mirounga leonina) and temporally overlapping whiskers from their mothers were analyzed. This included n = 1895 chronologically subsampled whisker segments for bulk …


Squids Use Multiple Escape Jet Patterns Throughout Ontogeny, Carly A. York, Ian K. Bartol, Paul S. Krueger, Joseph T. Thompson Jan 2020

Squids Use Multiple Escape Jet Patterns Throughout Ontogeny, Carly A. York, Ian K. Bartol, Paul S. Krueger, Joseph T. Thompson

Biological Sciences Faculty Publications

Throughout their lives, squids are both predators and prey for a multitude of animals, many of which are at the top of ocean food webs, making them an integral component of the trophic structure of marine ecosystems. The escape jet, which is produced by the rapid expulsion of water from the mantle cavity through a funnel, is central to a cephalopod's ability to avoid predation throughout its life. Although squid undergo morphological and behavioral changes and experience remarkably different Reynolds number regimes throughout their development, little is known about the dynamics and propulsive efficiency of escape jets throughout ontogeny. We …


Isothermal Environmental Heat Energy Utilization By Transmembrane Electrostatically Localized Protons At The Liquid-Membrane Interface, James Weifu Lee Jan 2020

Isothermal Environmental Heat Energy Utilization By Transmembrane Electrostatically Localized Protons At The Liquid-Membrane Interface, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

This study employing the latest theory on transmembrane electrostatic proton localization has now, for the first time, consistently elucidated a decades-longstanding bioenergetic conundrum in alkalophilic bacteria and more importantly discovered an entirely new feature: isothermal environmental heat utilization by electrostatically localized protons at the liquid-membrane interface. It was surprisingly revealed that the protonic motive force (equivalent to Gibbs free energy) from the isothermal environmental heat energy utilization through the electrostatically localized protons is not constrained by the overall energetics of the redox-driven proton pump system because of the following: (a) the transmembrane electrostatically localized protons are not free to move …


Insights Into The Feeding Behaviors And Biomechanics Of Varroa Destructor Mites On Honey Bee Pupae Using Electropenetrography And Histology, Andrew Y. Li, Steven C. Cook, Daniel E. Sonenshine, Francisco Pasada-Florez, Noble I.I. Noble, Joseph Mowery, Conner J. Gulbronson, Gary R. Bauchan Dec 2019

Insights Into The Feeding Behaviors And Biomechanics Of Varroa Destructor Mites On Honey Bee Pupae Using Electropenetrography And Histology, Andrew Y. Li, Steven C. Cook, Daniel E. Sonenshine, Francisco Pasada-Florez, Noble I.I. Noble, Joseph Mowery, Conner J. Gulbronson, Gary R. Bauchan

Biological Sciences Faculty Publications

Feeding behaviors and biomechanics of female Varroa destructor mites are revealed from AC-DC electropenetrography (EPG) recordings of mites feeding from Apis mellifera honey bee pupae and histology of mite internal ingestion apparatus. EPG signals characteristic of arthropod suction feeding (ingestion) were identified for mites that fed on pupae during overnight recordings. Ingestion by these mites was confirmed afterwards by observing internally fluorescent microbeads previously injected into their hosts. Micrographs of internal ingestion apparatus illustrate the connection between a gnathosomal tube and a pharyngeal lumen, which is surrounded by alternating dilator and constrictor muscles. Inspection of EPG signals showed the muscularized …


Vitellogenin Receptor As A Target For Tick Control: A Mini-Review, Robert D. Mitchell Iii, Daniel E. Sonenshine, Adalberto A. Pérez De León Jan 2019

Vitellogenin Receptor As A Target For Tick Control: A Mini-Review, Robert D. Mitchell Iii, Daniel E. Sonenshine, Adalberto A. Pérez De León

Biological Sciences Faculty Publications

While much effort has been put into understanding vitellogenesis in insects and other organisms, much less is known of this process in ticks. There are several steps that facilitate yolk formation in developing oocytes of which the vitellogenin receptor (VgR) is a key component. The tick VgR binds vitellogenin (Vg) circulating in the hemolymph to initiate receptor-mediated endocytosis and its transformation into vitellin (Vn). The conversion of Vg into Vn, the final form of the yolk protein, occurs inside oocytes of the female tick ovary. Vn is critical to tick embryos since it serves as the nutritional source for their …


Emerging Roles Of The Membrane Potential: Action Beyond The Action Potential, Lina Abdul Kadir, Michael Stacey, Richard Barrett-Jolley Nov 2018

Emerging Roles Of The Membrane Potential: Action Beyond The Action Potential, Lina Abdul Kadir, Michael Stacey, Richard Barrett-Jolley

Bioelectrics Publications

Whilst the phenomenon of an electrical resting membrane potential (RMP) is a central tenet of biology, it is nearly always discussed as a phenomenon that facilitates the propagation of action potentials in excitable tissue, muscle, and nerve. However, as ion channel research shifts beyond these tissues, it became clear that the RMP is a feature of virtually all cells studied. The RMP is maintained by the cell's compliment of ion channels. Transcriptome sequencing is increasingly revealing that equally rich compliments of ion channels exist in both excitable and non-excitable tissue. In this review, we discuss a range of critical roles …


Voltage Effects On Muscarinic Acetylcholine Receptor-Mediated Contractions Of Airway Smooth Muscle, Iurii Semenov, Robert Brenner Sep 2018

Voltage Effects On Muscarinic Acetylcholine Receptor-Mediated Contractions Of Airway Smooth Muscle, Iurii Semenov, Robert Brenner

Bioelectrics Publications

Studies have shown that the activity of muscarinic receptors and their affinity to agonists are sensitive to membrane potential. It was reported that in airway smooth muscle (ASM) depolarization evoked by high K+ solution increases contractility through direct effects on M3 muscarinic receptors. In this study, we assessed the physiological relevance of voltage sensitivity of muscarinic receptors on ASM contractility. Our findings reveal that depolarization by high K+ solution induces contraction in intact mouse trachea predominantly through activation of acetylcholine release from embedded nerves, and to a lesser extent by direct effects on M3 receptors. We therefore devised …


Effect Of Exercise Volume On Hdl-Cholesterol: A 7-Year Case Study, David P. Swain Sep 2018

Effect Of Exercise Volume On Hdl-Cholesterol: A 7-Year Case Study, David P. Swain

Human Movement Sciences Faculty Publications

Introduction: While exercise is known to increase HDL-cholesterol, it is not known if larger exercise volumes produce larger increases in HDL. However, the range of exercise volumes used in most training studies is limited. This report presents a case study of a middle-aged male who engaged in large variations of exercise volume over 7 years while frequently measuring HDL. The purpose was to determine if large increases in exercise volume were associated with larger increases in HDL than previously reported.

Methods: The subject maintained detailed logs of his main form of exercise, bicycling. These logs were analyzed to determine the …


Asymmetric Patterns Of Small Molecule Transport After Nanosecond And Microsecond Electropermeabilization, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier Jan 2018

Asymmetric Patterns Of Small Molecule Transport After Nanosecond And Microsecond Electropermeabilization, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier

Bioelectrics Publications

Imaging of fluorescent small molecule transport into electropermeabilized cells reveals polarized patterns of entry, which must reflect in some way the mechanisms of the migration of these molecules across the compromised membrane barrier. In some reports, transport occurs primarily across the areas of the membrane nearest the positive electrode (anode), but in others cathode-facing entry dominates. Here we compare YO-PRO-1, propidium, and calcein uptake into U-937 cells after nanosecond (6 ns) and microsecond (220 µs) electric pulse exposures. Each of the three dyes exhibits a different pattern. Calcein shows no preference for anode- or cathode-facing entry that is detectable with …


The Effect Of Tackling Training On Head Accelerations In Youth American Football, Eric Schussler, Richard J. Jagacinski, Susan E. White, Ajit M. Chaudhari, John A. Buford, James A. Onate Jan 2018

The Effect Of Tackling Training On Head Accelerations In Youth American Football, Eric Schussler, Richard J. Jagacinski, Susan E. White, Ajit M. Chaudhari, John A. Buford, James A. Onate

Rehabilitation Sciences Faculty Publications

Background: Many organizations have introduced frameworks to reduce the incidence of football related concussions through proper equipment fitting, coach education, and alteration of tackling technique.

Purpose: The purpose of this study was to examine the effects of training in a vertical, head up tackling style on the number of head accelerations experienced while tackling in a controlled laboratory situation. The authors hypothesized that training in a head up tackling technique would reduce the severity of head acceleration experienced by participants.

Design: Controlled Laboratory Study.

Methods: Twenty-four participants (11.5 ± 0.6 years old, 60.5 ± 2.2 in, 110 ± 18.4 lbs.) …


Blubber Transciptome Response To Acute Stress Axis Activation Involves Transient Charges In Adipogenesis And Lipolysis In Fast-Adapted Marine Mammal, J. I. Khudyakov, C. D. Champagne, L. M. Meneghetti, D. E. Crocker Feb 2017

Blubber Transciptome Response To Acute Stress Axis Activation Involves Transient Charges In Adipogenesis And Lipolysis In Fast-Adapted Marine Mammal, J. I. Khudyakov, C. D. Champagne, L. M. Meneghetti, D. E. Crocker

Biological Sciences Faculty Publications

Stress can compromise an animal's ability to conserve metabolic stores and participate in energy-demanding activities that are critical for fitness. Understanding how wild animals, especially those already experiencing physiological extremes (e.g. fasting), regulate stress responses is critical for evaluating the impacts of anthropogenic disturbance on physiology and fitness, key challenges for conservation. However, studies of stress in wildlife are often limited to baseline endocrine measurements and few have investigated stress effects in fasting-adapted species. We examined downstream molecular consequences of hypothalamic-pituitary-adrenal (HPA) axis activation by exogenous adrenocorticotropic hormone (ACTH) in blubber of northern elephant seals due to the ease of …


Hyper-Activation Of Pp60(Src) Limits Nitric Oxide Signaling By Increasing Asymmetric Dimethylarginine Levels During Acute Lung Injury, Sanjiv Kumar, Xutong Sun, Satish Kumar Noonepalle, Qing Lu, Evgeny Zemskov, Ting Wang, Saurabh Aggarwal, Christine Gross, Shruti Sharma, Ankit A. Sesai, John D. Catravas Jan 2017

Hyper-Activation Of Pp60(Src) Limits Nitric Oxide Signaling By Increasing Asymmetric Dimethylarginine Levels During Acute Lung Injury, Sanjiv Kumar, Xutong Sun, Satish Kumar Noonepalle, Qing Lu, Evgeny Zemskov, Ting Wang, Saurabh Aggarwal, Christine Gross, Shruti Sharma, Ankit A. Sesai, John D. Catravas

Bioelectrics Publications

The molecular mechanisms by which the endothelial barrier becomes compromised during lipopolysaccharide (LPS) mediated acute lung injury (ALI) are still unresolved. We have previously reported that the disruption of the endothelial barrier is due, at least in part, to the uncoupling of endothelial nitric oxide synthase (eNOS) and increased peroxynitrite-mediated nitration of RhoA. The purpose of this study was to elucidate the molecular mechanisms by which LPS induces eNOS uncoupling during ALI. Exposure of pulmonary endothelial cells (PAEC) to LPS increased pp60Src activity and this correlated with an increase in nitric oxide (NO) production, but also an increase in …


Transient Alt Activation Protects Human Primary Cells From Chromosome Instability Induced By Low Chronic Oxidative Stress, Elisa Coluzzi, Rossella Buonsante, Stefano Leone, Anthony J. Asmar, Kelley L. Miller, Daniela Cimini, Antonella Sgura Jan 2017

Transient Alt Activation Protects Human Primary Cells From Chromosome Instability Induced By Low Chronic Oxidative Stress, Elisa Coluzzi, Rossella Buonsante, Stefano Leone, Anthony J. Asmar, Kelley L. Miller, Daniela Cimini, Antonella Sgura

Bioelectrics Publications

Cells are often subjected to the effect of reactive oxygen species (ROS) as a result of both intracellular metabolism and exposure to exogenous factors. ROS-dependent oxidative stress can induce 8-oxodG within the GGG triplet found in the G-rich human telomeric sequence (TTAGGG), making telomeres highly susceptible to ROS-induced oxidative damage. Telomeres are nucleoprotein complexes that protect the ends of linear chromosomes and their dysfunction is believed to affect a wide range of cellular and/or organismal processes. Acute oxidative stress was shown to affect telomere integrity, but how prolonged low level oxidative stress, which may be more physiologically relevant, affects telomeres …


Cloning, Characteristics, And Functional Analysis Of Rabbit Nadph Oxidase 5, Feng Chen, Caiyong Yin, Christiana Dimitropoulou, David J.R. Fulton Jul 2016

Cloning, Characteristics, And Functional Analysis Of Rabbit Nadph Oxidase 5, Feng Chen, Caiyong Yin, Christiana Dimitropoulou, David J.R. Fulton

Bioelectrics Publications

Background: Nox5 was the last member of the Nox enzyme family to be identified. Functionally distinct from the other Nox isoforms, our understanding of its physiological significance has been hampered by the absence of Nox5 in mouse and rat genomes. Nox5 is present in the genomes of other species such as the rabbit that have broad utility as models of cardiovascular disease. However, the mRNA sequence, characteristics, and functional analysis of rabbit Nox5 has not been fully defined and were the goals of the current study.

Methods: Rabbit Nox5 was amplified from rabbit tissue, cloned, and sequenced. COS-7 cells were …


Nanosecond Pulsed Platelet-Rich Plasma (Nsprp) Improves Mechanical And Electrial Cardiac Function Following Myocardial Reperfusion Injury, Barbara Y. Hargrave, Frency Varghese, Nektarios Barabutis, John Catravas, Christian Zemlin Jan 2016

Nanosecond Pulsed Platelet-Rich Plasma (Nsprp) Improves Mechanical And Electrial Cardiac Function Following Myocardial Reperfusion Injury, Barbara Y. Hargrave, Frency Varghese, Nektarios Barabutis, John Catravas, Christian Zemlin

Medical Diagnostics & Translational Sciences Faculty Publications

Ischemia and reperfusion (I/R) of the heart is associated with biochemical and ionic changes that result in cardiac contractile and electrical dysfunction. In rabbits, platelet-rich plasma activated using nanosecond pulsed electric fields (nsPRP) has been shown to improve left ventricular pumping. Here, we demonstrate that nsPRP causes a similar improvement in mouse left ventricular function. We also show that nsPRP injection recovers electrical activity even before reperfusion begins. To uncover the mechanism of nsPRP action, we studied whether the enhanced left ventricular function in nsPRP rabbit and mouse hearts was associated with increased expression of heat-shock proteins and altered mitochondrial …


Mitochondrial Function Assessed By 31p Mrs And Bold Mri In Non-Obese Type 2 Diabetic Rats, Yuchi Liu, Xunbai Mei, Jielei Li, Nicola Lai, Xin Yu Jan 2016

Mitochondrial Function Assessed By 31p Mrs And Bold Mri In Non-Obese Type 2 Diabetic Rats, Yuchi Liu, Xunbai Mei, Jielei Li, Nicola Lai, Xin Yu

Electrical & Computer Engineering Faculty Publications

The study aims to characterize age-associated changes in skeletal muscle bioenergetics by evaluating the response to ischemia-reperfusion in the skeletal muscle of the Goto-Kakizaki (GK) rats, a rat model of non-obese type 2 diabetes (T2D). 31P magnetic resonance spectroscopy (MRS) and blood oxygen level-dependent (BOLD) MRI was performed on the hindlimb of young (12 weeks) and adult (20 weeks) GK and Wistar (control) rats. 31P-MRS and BOLD-MRI data were acquired continuously during an ischemia and reperfusion protocol to quantify changes in phosphate metabolites and muscle oxygenation. The time constant of phosphocreatine recovery, an index of mitochondrial oxidative capacity, …


Gender Differences In Vo2 And Hr Kinetics At The Onset Of Moderate And Heavy Exercise Intensity In Adolescents, Nicola Lai, Alessandro Martis, Alfredo Belfiori, Fatima Tolentino-Silva, Melita M. Nasca, James Strainic, Marco E. Cabrera Jan 2016

Gender Differences In Vo2 And Hr Kinetics At The Onset Of Moderate And Heavy Exercise Intensity In Adolescents, Nicola Lai, Alessandro Martis, Alfredo Belfiori, Fatima Tolentino-Silva, Melita M. Nasca, James Strainic, Marco E. Cabrera

Electrical & Computer Engineering Faculty Publications

The majority of the studies on VO2 kinetics in pediatric populations investigated gender differences in prepubertal children during submaximal intensity exercise, but studies are lacking in adolescents. The purpose of this study was to test the hypothesis that gender differences exist in the VO2 and heart rate (HR) kinetic responses to moderate (M) and heavy (H) intensity exercise in adolescents. Twenty-one healthy African-American adolescents (9 males, 15.8 ± 1.1 year; 12 females, 15.7 ± 1 year) performed constant work load exercise on a cycle ergometer at M and H. The VO2 kinetics of the male group was …


Rnd3 As A Novel Target To Ameliorate Microvascular Leakage, Jerome W. Breslin, Dayle A. Daines, Travis M. Doggett, Kristine H. Kurtz, Flavia M. Souza-Smith, Xun E. Zhang, Mack H. Wu, Sarah Y. Yuan Jan 2016

Rnd3 As A Novel Target To Ameliorate Microvascular Leakage, Jerome W. Breslin, Dayle A. Daines, Travis M. Doggett, Kristine H. Kurtz, Flavia M. Souza-Smith, Xun E. Zhang, Mack H. Wu, Sarah Y. Yuan

Biological Sciences Faculty Publications

Background -Microvascular leakage of plasma proteins is a hallmark of inflammation that leads to tissue dysfunction. There are no current therapeutic strategies to reduce microvascular permeability. The purpose of this study was to identify the role of Rnd3, an atypical Rho family GTPase, in the control of endothelial barrier integrity. The potential therapeutic benefit of Rnd3 protein delivery to ameliorate microvascular leakage was also investigated.

Methods and Results-Using immunofluorescence microscopy, Rnd3 was observed primarily in cytoplasmic areas around the nuclei of human umbilical vein endothelial cells. Permeability to fluorescein isothiocyanate-albumin and transendothelial electrical resistance of human umbilical vein …


Hsp90 Inhibition Suppresses Nf-Κb Transcriptional Activation Via Sirt-2 In Human Lung Microvascular Endothelial Cells, Gagan S. Thangjam, Charalampos Birmpas, Nektarios Barabutis, Betsy W. Gregory, Mary Ann Clemens, Joseph R. Newton, David Fulton, John D. Catravas Jan 2016

Hsp90 Inhibition Suppresses Nf-Κb Transcriptional Activation Via Sirt-2 In Human Lung Microvascular Endothelial Cells, Gagan S. Thangjam, Charalampos Birmpas, Nektarios Barabutis, Betsy W. Gregory, Mary Ann Clemens, Joseph R. Newton, David Fulton, John D. Catravas

Bioelectrics Publications

The ability of anti-heat shock protein 90 (Hsp90) drugs to attenuate NF-κB-mediated transcription is the major basis for their anti-inflammatory properties. While the molecular mechanisms underlying this effect are not clear, they appear to be distinct in human endothelial cells. We now show for the first time that type 2 sirtuin (Sirt-2) histone deacetylase binds human NF-κB target gene promoter and prevents the recruitment of NF-κB proteins and subsequent assembly of RNA polymerase II complex in human lung microvascular endothelial cells. Hsp90 inhibitors stabilize the Sirt-2/promoter interaction and impose a “transcriptional block,” which is reversed by either inhibition or downregulation …


Physical Activity/Exercise And Diabetes: A Position Statement Of The American Diabetes Association, Sheri R. Colberg, Ronald J. Sigal, Jane E. Yardley, Michael C. Riddell, David W. Dunstan, Paddy C. Dempsey Jan 2016

Physical Activity/Exercise And Diabetes: A Position Statement Of The American Diabetes Association, Sheri R. Colberg, Ronald J. Sigal, Jane E. Yardley, Michael C. Riddell, David W. Dunstan, Paddy C. Dempsey

Human Movement Sciences Faculty Publications

The adoption and maintenance of physical activity are critical foci for blood glucose management and overall health in individuals with diabetes and prediabetes. Recommendations and precautions vary depending on individual characteristics and health status. In this Position Statement, we provide a clinically oriented review and evidence-based recommendations regarding physical activity and exercise in people with type 1 diabetes, type 2 diabetes, gestational diabetes mellitus, and prediabetes.

Physical activity includes all movement that increases energy use, whereas exercise is planned, structured physical activity. Exercise improves blood glucose control in type 2 diabetes, reduces cardiovascular risk factors, contributes to weight loss, and …


P53: "The Wall Watcher", Nektarios Barabutis, John D. Catravas Oct 2015

P53: "The Wall Watcher", Nektarios Barabutis, John D. Catravas

Bioelectrics Publications

No abstract provided.


Picosecond To Terahertz Perturbation Of Interfacial Water And Electropermeabilization Of Biological Membranes, P. Thomas Vernier, Zachary A. Levine, Ming-Chak Ho, Shu Xiao, Iurii Semenov, Andrei G. Pakhomov Jan 2015

Picosecond To Terahertz Perturbation Of Interfacial Water And Electropermeabilization Of Biological Membranes, P. Thomas Vernier, Zachary A. Levine, Ming-Chak Ho, Shu Xiao, Iurii Semenov, Andrei G. Pakhomov

Bioelectrics Publications

Non-thermal probing and stimulation with subnanosecond electric pulses and terahertz electromagnetic radiation may lead to new, minimally invasive diagnostic and therapeutic procedures and to methods for remote monitoring and analysis of biological systems, including plants, animals, and humans. To effectively engineer these still-emerging tools, we need an understanding of the biophysical mechanisms underlying the responses that have been reported to these novel stimuli. We show here that subnanosecond (≤500 ps) electric pulses induce action potentials in neurons and cause calcium transients in neuroblastoma-glioma hybrid cells, and we report complementary molecular dynamics simulations of phospholipid bilayers in electric fields in which …