Physiology Commons^™

Chemical-Free Technique To Study The Ultrastructure Of Primary Cilium, Ashraf M. Mohieldin, Wissam A. Aboualaiwi, Min Gao, Surya M. Nauli

Pharmacy Faculty Articles and Research

A primary cilium is a hair-like structure with a width of approximately 200 nm. Over the past few decades, the main challenge in the study of the ultrastructure of cilia has been the high sensitivity of cilia to chemical fixation, which is required for many imaging techniques. In this report, we demonstrate a combined high-pressure freezing (HPF) and freeze-fracture transmission electron microscopy (FFTEM) technique to examine the ultrastructure of a cilium. Our objective is to develop an optimal high-resolution imaging approach that preserves cilia structures in their best natural form without alteration of cilia morphology by chemical fixation interference. Our …

Bdnf Contributes To Angiotensin Ii-Mediated Reductions In Peak Voltage-Gated K+ Current In Cultured Cath.A Cells., Bryan K. Becker, Han-Jun Wang, Changhai Tian, Irving H. Zucker

Journal Articles: Cellular & Integrative Physiology

Increased central angiotensin II (Ang II) levels contribute to sympathoexcitation in cardiovascular disease states such as chronic heart failure and hypertension. One mechanism by which Ang II increases neuronal excitability is through a decrease in voltage-gated, rapidly inactivating K(+) current (IA); however, little is known about how Ang II signaling results in reduced IA. Brain-derived neurotrophic factor (BDNF) has also been demonstrated to decrease IA and has signaling components common to Ang II. Therefore, we hypothesized that Ang II-mediated suppression of voltage-gated K(+) currents is due, in part, to BDNF signaling. Differentiated CATH.a, catecholaminergic cell line treated with BDNF for …

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

Bioelectrics Publications

No abstract provided.

Relevance Of The Carotid Body Chemoreflex In The Progression Of Heart Failure., David C. Andrade, Claudia Lucero, Camilo Toledo, Carlos Madrid, Noah J. Marcus, Harold D. Schultz, Rodrigo Del Rio

Journal Articles: Cellular & Integrative Physiology

Chronic heart failure (CHF) is a global health problem affecting millions of people. Autonomic dysfunction and disordered breathing patterns are commonly observed in patients with CHF, and both are strongly related to poor prognosis and high mortality risk. Tonic activation of carotid body (CB) chemoreceptors contributes to sympathoexcitation and disordered breathing patterns in experimental models of CHF. Recent studies show that ablation of the CB chemoreceptors improves autonomic function and breathing control in CHF and improves survival. These exciting findings indicate that alterations in CB function are critical to the progression of CHF. Therefore, better understanding of the physiology of …

Elongation Factor-P At The Crossroads Of The Host-Endosymbiont Interface, Andrei Rajkovic, Anne Witzky, William Navarre, Andrew J. Darwin, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is an ancient bacterial translational factor that aids the ribosome in polymerizing oligo-prolines. EF-P structurally resembles tRNA and binds in-between the exit and peptidyl sites of the ribosome to accelerate the intrinsically slow reaction of peptidyl-prolyl bond formation. Recent studies have identified in separate organisms, two evolutionarily convergent EF-P post-translational modification systems (EPMS), split predominantly between gammaproteobacteria, and betaproteobacteria. In both cases EF-P receives a post-translational modification, critical for its function, on a highly conserved residue that protrudes into the peptidyl-transfer center of the ribosome. EPMSs are comprised of a gene(s) that synthesizes the precursor molecule …

Monitoring The Progression Of Spontaneous Articular Cartilage Healing With Infrared Spectroscopy, Megan P. O'Brien, Madhuri Penmatsa, Uday Palukuru, Paul West, Xu Yang, Mathias P. G. Bostrom, Theresa Freeman, Nancy Pleshko

Publications and Research

Objective. Evaluation of early compositional changes in healing articular cartilage is critical for understanding tissue repair and for therapeutic decision-making. Fourier transform infrared imaging spectroscopy (FT-IRIS) can be used to assess the molecular composition of harvested repair tissue. Furthermore, use of an infrared fiber-optic probe (IFOP) has the potential for translation to a clinical setting to provide molecular information in situ. In the current study, we determined the feasibility of IFOP assessment of cartilage repair tissue in a rabbit model, and assessed correlations with gold-standard histology.

Design. Bilateral osteochondral defects were generated in mature white New Zealand rabbits, and …

Editorial: Carotid Body: A New Target For Rescuing Neural Control Of Cardiorespiratory Balance In Disease., Rodrigo Del Rio, Rodrigo Iturriaga, Harold D. Schultz

Journal Articles: Cellular & Integrative Physiology

No abstract provided.

Cyclic Rhamnosylated Elongation Factor P Establishes Antibiotic Resistance In Pseudomonas Aeruginosa, Andrei Rajkovic, Sarah Erickson, Anne Witzky, Owen E. Branson, Jin Seo, Philip R. Gafken, Michael A. Frietas, Julian P. Whitelegge, Kym F. Faull, William Wiley Navarre, Andrew J. Darwin, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is a ubiquitous bacterial protein that is required for the synthesis of poly-proline motifs during translation. In Escherichia coli and Salmonella enterica, the posttranslational β-lysylation of Lys34 by the PoxA protein is critical for EF-P activity. PoxA is absent from many bacterial species such as Pseudomonas aeruginosa, prompting a search for alternative EF-P posttranslation modification pathways. Structural analyses of P. aeruginosa EF-P revealed the attachment of a single cyclic rhamnose moiety to an Arg residue at a position equivalent to that at which β-Lys is attached to E. coli EF-P. Analysis of the genomes …

Orexin Receptor Activation Generates Gamma Band Input To Cholinergic And Serotonergic Arousal System Neurons And Drives An Intrinsic Ca(2+)-Dependent Resonance In Ldt And Ppt Cholinergic Neurons, Masaru Ishibashi, Iryna Gumenchuk, Bryan Kang, Catherine Steger, Elizabeth Lynn, Nancy Molina, Leonard M. Eisenberg, Christopher S. Leonard

NYMC Faculty Publications

A hallmark of the waking state is a shift in EEG power to higher frequencies with epochs of synchronized intracortical gamma activity (30-60 Hz) - a process associated with high-level cognitive functions. The ascending arousal system, including cholinergic laterodorsal (LDT) and pedunculopontine (PPT) tegmental neurons and serotonergic dorsal raphe (DR) neurons, promotes this state. Recently, this system has been proposed as a gamma wave generator, in part, because some neurons produce high-threshold, Ca(2+)-dependent oscillations at gamma frequencies. However, it is not known whether arousal-related inputs to these neurons generate such oscillations, or whether such oscillations are ever transmitted to neuronal …

Discovering The Sequence Specificity Of Human Dyrk2 And Dyrk4, Julie Klaric

University Scholar Projects

Protein phosphorylation is a post-translational modification (PTM) that is ubiquitous in regulating cellular processes. It is the most common PTM used in signal translation. Protein kinases are the class of enzymes that catalyze the transfer of a phosphate group from ATP to a specific amino acid on a substrate protein. In eukaryotes, kinases generally add a phosphate to serine, threonine, or tyrosine residues. Short linear patterns in the amino acid sequence of the substrate protein help guide the protein kinase to the correct residue to be phosphorylated. However, these patterns, or “motifs,” as well as the complete list of substrates …

The Development Of Skeletal Muscle In Young Horses: An Ultrasonography And Satellite Cell Approach, Emma K. Lavigne

Honors Scholar Theses

Muscle growth in young horses is characterized by an increase in muscle cross-sectional area, which can be accomplished through the activation and differentiation of satellite cells. Satellite cells can be stimulated or inhibited in response to different cytokines and growth factors and are key mediators of muscle hypertrophy and regeneration. The aim of this study was to investigate the growth of the longissimus dorsi (LD) muscle in horses under 5 years of age and to obtain preliminary data on satellite cell behavior in foals. The area, width, height, and subcutaneous fat were measured using ultrasonography at 6-month increments over the …

Pathological Effects Of Repeated Concussive Tbi In Mouse Models: Periventricular Damage And Ventriculomegaly, Richard H. Wolferz Jr.

Honors Scholar Theses

Repeated concussive traumatic brain injury (rcTBI) is the most prominent form of head injury affecting the brain, with an estimated 1.7 million Americans affected each year (Kuhn 2012). Neurologists have been concerned about the danger of repeated head impacts since the 1920’s, but researchers have only begun to understand the long-term effects of rcTBI (McKee 2009). Although symptoms can be as mild as dizziness, current research suggests that multiple concussions can lead to a progressive degenerative brain disease known as chronic traumatic encephalopathy (CTE) (Luo 2008, McKee 2009, Kane 2013). Research on the brain is just beginning to scratch the …

Exercise Ameliorates High Fat Diet Induced Cardiac Dysfunction By Increasing Interleukin 10., Varun Kesherwani, Vishalakshi Chavali, Bryan T. Hackfort, Suresh C. Tyagi, Paras K. Mishra

Journal Articles: Cellular & Integrative Physiology

Increasing evidence suggests that a sedentary lifestyle and a high fat diet (HFD) leads to cardiomyopathy. Moderate exercise ameliorates cardiac dysfunction, however underlying molecular mechanisms are poorly understood. Increased inflammation due to induction of pro-inflammatory cytokine such as tumor necrosis factor-alpha (TNF-α) and attenuation of anti-inflammatory cytokine such as interleukin 10 (IL-10) contributes to cardiac dysfunction in obese and diabetics. We hypothesized that exercise training ameliorates HFD- induced cardiac dysfunction by mitigating obesity and inflammation through upregulation of IL-10 and downregulation of TNF-α. To test this hypothesis, 8 week old, female C57BL/6J mice were fed with HFD and exercised (swimming …

Induction Of Autophagy Markers Is Associated With Attenuation Of Mir-133a In Diabetic Heart Failure Patients Undergoing Mechanical Unloading., Shyam Sundar Nandi, Michael J. Duryee, Hamid R. Shahshahan, Geoffrey M. Thiele, Daniel R. Anderson, Paras K. Mishra

Journal Articles: Cellular & Integrative Physiology

Autophagy is ubiquitous in all forms of heart failure and cardioprotective miR-133a is attenuated in human heart failure. Previous reports from heart failure patients undergoing left ventricular assist device (LVAD) implantation demonstrated that autophagy is upregulated in the LV of the failing human heart. Studies in the murine model show that diabetes downregulates miR-133a. However, the role of miR-133a in the regulation of autophagy in diabetic hearts is unclear. We tested the hypothesis that diabetes exacerbates cardiac autophagy by inhibiting miR-133a in heart failure patients undergoing LVAD implantation. The miRNA assay was performed on the LV of 15 diabetic (D) …

Theoretical Investigation Of Intra- And Inter-Cellular Spatiotemporal Calcium Patterns In Microcirculation, Jaimit B. Parikh

FIU Electronic Theses and Dissertations

Microcirculatory vessels are lined by endothelial cells (ECs) which are surrounded by a single or multiple layer of smooth muscle cells (SMCs). Spontaneous and agonist induced spatiotemporal calcium (Ca²⁺) events are generated in ECs and SMCs, and regulated by complex bi-directional signaling between the two layers which ultimately determines the vessel tone. The contractile state of microcirculatory vessels is an important factor in the determination of vascular resistance, blood flow and blood pressure. This dissertation presents theoretical insights into some of the important and currently unresolved phenomena in microvascular tone regulation. Compartmental and continuum models of isolated EC …

The Proteomic Response In The Crustacean Molting Gland Of Land Crab Gecarcinus Lateralis In Response To Artificially Induced Molting Throughout Its Molting Cycle., Andrea Reider, Talia B. Head, Lars Tomanek, Donald L. Mykles

STAR Program Research Presentations

Molting in crustaceans is a highly complex physiological process involving negative regulation by two paired endocrine glands, the X-organ/sinus gland complex (XO/SG) and the Y-organ (YO). The XO/SG complex is responsible for making molt-inhibiting hormone (MIH) which negatively regulates synthesis of molting hormones (ecdysteroids) by the YO. Eyestalk ablation (ESA) removes the source of MIH and provides an experimental means to manipulate and induce molting, although the physiological effects of ESA on the YO have not been fully characterized. Analysis of gene expression in the XOs and YOs has lead to the development of a proposed molecular signaling pathway which …

Clique Topology Reveals Intrinsic Geometric Structure In Neural Correlations, Chad Giusti, Eva Pastalkova, Carina Curto, Vladimir Itskov

Department of Mathematics: Faculty Publications

Detecting meaningful structure in neural activity and connectivity data is challenging in the presence of hidden nonlinearities, where traditional eigenvalue-based methods may be misleading. We introduce a novel approach to matrix analysis, called clique topology, that extracts features of the data invariant under nonlinear monotone transformations. These features can be used to detect both random and geometric structure, and depend only on the relative ordering of matrix entries. We then analyzed the activity of pyramidal neurons in rat hippocampus, recorded while the animal was exploring a 2D environment, and confirmed that our method is able to detect geometric organization using …

Human Anatomy And Physiology Preparatory Course (1st Edition), Carlos Liachovitzky

Open Educational Resources

The overall purpose of this preparatory course textbook is to help students familiarize with some terms and some basic concepts they will find later in the Human Anatomy and Physiology I course.

The organization and functioning of the human organism generally is discussed in terms of different levels of increasing complexity, from the smallest building blocks to the entire body. This Anatomy and Physiology preparatory course covers the foundations on the chemical level, and a basic introduction to cellular level, organ level, and organ system levels. There is also an introduction to homeostasis at the beginning.

Physiological Performance Of Warm-Adapted Marine Ectotherms: Thermal Limits Of Mitochondrial Energy Transduction Efficiency, Eloy Martinez, Eric Hendricks, Michael Menze, Joseph Torres

Faculty Research & Creative Activity

Thermal regimes in aquatic systems have profound implications for the physiology of ectotherms. In particular, the effect of elevated temperatures on mitochondrial energy transduction (i.e. energy from carbon substrates to ATP) in tropical and subtropical teleosts may have profound consequences on organismal performance and population viability. Upper and lower whole-organism critical temperatures for teleosts suggest that subtropical and tropical species are not susceptible to the warming trends associated with climate change, but sub-lethal effects on energy transduction efficiency and population dynamics remain unclear. The goal of the present study was to compare the thermal sensitivity of processes associated with mitochondrial …

Acute Toxicity Assessment Of N,N-Diethyl-M-Toluamide (Deet) On The Photosynthetic Activity Of The Dinoflagellate Gymnodinium Instriatum, Eloy Martinez, Sylvia Velez, Marietta Mayo, Miguel Sastre

Faculty Research & Creative Activity

Despite the ubiquitous occurrence of N, N-diethyl-m-toluamide (DEET) in aquatic systems, assessments evaluating the toxicity of DEET on phytoplankton species are summed to a single study on a unicellular green alga. In particular, the toxicological effects of DEET in dinoflagellates are unknown. In this study, we employed the mixotrophic dinoflagellate Gymnodinium instriatum as a study system to evaluate acute effects of DEET on the oxygen flux of laboratory cultures. This study reports an inhibitory reaction model of DEET described by the equation y = 4.99 x 0.54, where y represents the percent inhibition of oxygen flux and x represents DEET …

Transfer Rna Comes Of Age, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

"The year the journal RNA was founded was slated by some in scientific publishing to be the year that one particular type of RNA's run in the spotlight would end. In 1995 I had recently started as a post-doc with Dieter Söll at Yale when he came into the lab to solemnly inform us all that an editor at a certain (S)cience journal had just told him “we won't be publishing any more tRNA papers.” For a post-doc who had migrated across the Atlantic for the sole purpose of furthering his career by working on tRNA this was not great …