Cellular and Molecular Physiology Commons^™

Morphological And Moisture Availability Controls Of The Leaf Area-To-Sapwood Area Ratio: Analysis Of Measurements On Australian Trees, Henrique Furstenau Togashi, Iain Colin Prentice, Bradley John Evans, David Ian Forrester, Paul Drake, Paul Feikema, Kim Brooksbank, Derek Eamus, Daniel Taylor

Natural Resources Research Articles

1. The leaf area-to-sapwood area ratio (LA:SA) is a key plant trait that links photosynthesis to transpiration. The pipe model theory states that the sapwood cross-sectional area of a stem or branch at any point should scale isometrically with the area of leaves distal to that point. Optimization theory further suggests that LA:SA should decrease toward drier climates. Although acclimation of LA:SA to climate has been reported within species, much less is known about the scaling of this trait with climate among species.
2. We compiled LA:SA measurements from 184 species of Australian evergreen angiosperm trees. The pipe model was …

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 …

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 …

The Physiological Stress Response Caused By Hypoxia And Reperfusion Injury In Striped Bass (Morone Saxatilis) And Nile Tilapia (Oreochromis Niloticus), Amanda C. Reynolds

College of Graduate Studies: Theses & Dissertations

Approximately five million people in the United States are affected by cardiovascular related diseases yearly contributing to 300,000 annual deaths, making CVD the leading cause of mortality worldwide. It has been suggested that apoptosis (programmed cell death) contributes to the pathogenesis of cardiovascular diseases. When blood flow is reduced or cut off from the heart, usually by a thrombus, this results in oxygen deprivation (hypoxia) to the cardiomyocytes (heart cells). In response to this hypoxic stress, cardiomyocytes will undergo apoptosis. Since many species of fish can survive levels of hypoxia that would be fatal to mammals, fish are an ideal …

D-Galactose Decreases Mitoneet Levels In Liver Cancer Cells: Impact On Cellular Bioenergetics, Sudip Paudel

Masters Theses

Galactose is a simple sugar that at supraphysiological concentrations accelerates aging and age-related complications, which lead to impaired mitochondrial functions. MitoNEET is a small mitochondrial membrane protein with a molecular mass of 12.2 kDa that functions in diabetes, iron metabolism, regulation of oxidative phosphorylation (OXPHOS) and reactive oxygen species (ROS) homeostasis. MitoNEET knockdown increases cellular respiration rates and ROS levels similar to galactose treatment. Pioglitazone, an antidiabetic drug, binds to mitoNEET and ameliorates galactose toxicity. Cellular mitoNEET levels, exposure of cells to galactose medium, and pioglitazone treatment directly influence cellular respiration. To elucidate the role of mitoNEET in galactose induced …

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 …

The Effects Of Lampricide 3-Trifluoromethyl-4-Nitrophenol Toxicity On The Gills Of Larval Sea Lamprey And Non-Target Rainbow Trout And Lake Sturgeon, Lisa A. Sorensen

Theses and Dissertations (Comprehensive)

The pesticide, 3-trifluoromethyl-4-nitrophenol (TFM), is widely used in the Great Lakes to control invasive sea lampreys (Petromyzon marinus) populations, but much about its sub-lethal effects remains unknown. A better understanding of its toxicity is needed to improve TFM effectiveness and to protect non-target organisms from its potential adverse effects. The objectives of this thesis were to test the following two hypotheses: (1) impairment of mitochondrial ATP production by TFM interferes with ATP-dependent ion-uptake by fish, leading to altered electrolyte balance, and (2) perturbations of gill function by TFM are exacerbated in soft, ion poor water (SW; 40 mg …

Estimates Of Persistent Inward Current In Human Motor Neurons During Postural Sway, Ryan Foley, Jayne M. Kalmar Dr.

Theses and Dissertations (Comprehensive)

Persistent inward current (PIC) is a membrane property critical for increasing gain of motor neuron output. In humans, most estimates of PIC are made from plantarflexor or dorsiflexor motor units with the participant in a seated position with the knee flexed. This seated and static posture neglects the task-dependent nature of the monoaminergic drive that modulates PIC activation. Seated estimates may drastically underestimate the amount of PIC that occurs in human motor neurons during functional movement. The current study estimated PIC using the conventional paired motor unit technique which uses the difference between reference unit firing frequency at test unit …

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.

Mitochondrial Therapeutics During Ischemia-Reperfusion; Modulation Of Complex I: Effect Of Metformin., Shawn Y. Sunu

Theses and Dissertations

The modulation of the electron transport during ischemia-reperfusion has been shown to be protective. We hypothesized that metformin, a Complex I inhibitor, may exhibit characteristics of a pharmacological agent that could achieve long-term therapeutic intervention against ischemia-reperfusion injury. Mitochondria were harvested from adult male mice and incubated with or without metformin at 30^oC for 15 minutes, while being shaken at 300 rpm. Metformin decreased Complex I oxidative phosphorylation and Complex I activity. However, metformin also increased injury and decreased the maximum membrane potential. Even though there was a decrease in maximum membrane potential, the proton motive force (PMF) …

Molecular Identification And Functional Characteristics Of Peptide Transporter 1 (Pept1) In The Bonnethead Shark (Sphyrna Tiburo), Hannah Hart

UNF Graduate Theses and Dissertations

Many elasmobranchs are considered top predators with worldwide distribution, and in general these fish play an important role in the transfer of energy from the lower to the upper trophic levels within the marine ecosystem. Despite this, little research has been done regarding the rates of prey ingestion, digestion, and the processes of energy and nutrient absorption. Specifically understudied is enzymatic digestion within the intestinal brush border, which functions to break down macromolecules into smaller subunits for luminal absorption across the gastrointestinal epithelium. Given their carnivorous diet, the present study sought to expand knowledge on nutrient intake in elasmobranchs by …

Biological And Physiological Condition Of Juvenile California Halibut (Paralichthys Californicus) Exposed To A Contamination Gradient In Mission Bay, Ca, Kevin Stolzenbach

Theses

Contaminated sediments in marine environments have been shown to be good indicators of ecological risk and a means to assess anthropogenic impacts on marine habitats and the animals that inhabit them (Long et al. 1995, Rattner 2009). Estuarine sediments are especially complex media with regard to physical, chemical, and biological characteristics that trap, store, modify and sometimes release contaminants to the biota (Long et al. 1995). Especially vulnerable are animals that are in constant contact with the sediments, such as flatfishes that partially bury themselves for camouflage (Costa et al. 2011). Impacts can be assessed in a number of ways, …

Regulation Of Dkk1, An Inhibitor Of The Wnt Signaling Pathway, By Dax-1 In Mouse Embryonic Stem Cells, Victor D. Gavallos

Undergraduate Honors Theses

DAX-1 is known to play a key role in the maintenance of pluripotency in mouse embryonic stem cells (mESC), such that elimination of DAX-1 (through methods such as RNAi) leads to the differentiation of ESC (Khalfallah et al. 2009). Earlier research by the Tzagarakis-Foster lab identified target genes of DAX-1 in mESC through PCR array methodology (Torres 2013). The Dickkopf 1 gene (Dkk1) was identified as a potential target of DAX-1 by these studies and has since been confirmed to be a DAX-1 target in mESC. However, to date very little is understood of the mechanism of DAX-1 repression of …

Effect Of Hydrogen Peroxide On The Biosynthesis Of Heme And Proteins: Potential Implications For The Partitioning Of Glu-TrnaGlu Between These Pathways, Carolina Farah, Gloria Levicán, Michael Ibba, Omar Orellana

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Glutamyl-tRNA (Glu-tRNA^Glu) is the common substrate for both protein translation and heme biosynthesis via the C5 pathway. Under normal conditions, an adequate supply of this aminoacyl-tRNA is available to both pathways. However, under certain circumstances, Glu-tRNA^Glu can become scarce, resulting in competition between the two pathways for this aminoacyl-tRNA. In Acidithiobacillus ferrooxidans, glutamyl-tRNA synthetase 1 (GluRS1) is the main enzyme that synthesizes Glu-tRNA^Glu. Previous studies have shown that GluRS1 is inactivated in vitro by hydrogen peroxide (H₂O₂). This raises the question as to whether H₂O₂ negatively affects …

Prostate Field Cancerization -- Thinking Outside The Tumor, Dor Shoshan, Marco Bisoffi

Student Scholar Symposium Abstracts and Posters

Prostate field cancerization (or field effect) is characterized by the presence of molecular alterations in histologically normal tissues adjacent to adenocarcinomas. Accordingly, our research indicates deregulated expression of several proteins that define this type of molecular pathology. The scope of the present study was to determine the expression of the key transcription factor and potential marker of field cancerization early growth response 1 (EGR-1) in human prostate tissues derived from prostatectomies and biopsy cores.

EGR-1 was detected by immunofluorescence using a polyclonal anti-human EGR-1 and Alexa Fluor 488-conjugated secondary antibodies. EGR-1 expression was quantitated by determining the pixel count per …

Over-Expression Of Copper/Zinc Superoxide Dismutase In The Median Preoptic Nucleus Attenuates Chronic Angiotensin Ii-Induced Hypertension In The Rat., John P. Collister, Mitch Bellrichard, Donna Drebes, David Nahey, Jun Tian, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

The brain senses circulating levels of angiotensin II (AngII) via circumventricular organs, such as the subfornical organ (SFO), and is thought to adjust sympathetic nervous system output accordingly via this neuro-hormonal communication. However, the cellular signaling mechanisms involved in these communications remain to be fully understood. Previous lesion studies of either the SFO, or the downstream median preoptic nucleus (MnPO) have shown a diminution of the hypertensive effects of chronic AngII, without providing a clear explanation as to the intracellular signaling pathway(s) involved. Additional studies have reported that over-expressing copper/zinc superoxide dismutase (CuZnSOD), an intracellular superoxide (O2·-) scavenging enzyme, in …

Exploring The Glucocorticoid Actions Of 1Α-Hydroxycorticosterone (1Α-Oh-B) In The Elasmobranch Fishes, Faith Nichole Lambert

Master's Theses

The corticosteroid 1α-hydroxycorticosterone (1α-OH-B) is unique to the elasmobranch fishes. It is thought that 1α-OH-B acts as both the primary glucocorticoid (GC) and mineralocorticoid (MC) in these fishes, a dual role analogous to that of cortisol in the teleost fishes. The MC characteristics of 1α-OH-B are well supported, but data supporting its GC functions are lacking. In this study, the putative GC actions of 1α-OH-B were examined. The first experiment characterized the physiological stress response of the Atlantic stingray (Dasyatis sabina) to air exposure, with particular regards to the roles of corticosteroids and metabolic fuels. Results demonstrate that …

Regulation Of Functional Expression Of Mechanosensitive Trpv4 Channel In The Distal Nephron By Dietary Potassium And Sodium Intake, Nabila Boukelmoune

Dissertations and Theses (Open Access)

The Ca²⁺-permeable TRPV4 channel is predominantly expressed in the distal nephron (DN) and its activity is essential for [Ca²⁺]_i elevations in response to increased tubular flow. Here, I probed the physiological mechanisms controlling TRPV4 function and expression in the DN. I found that renal TRPV4 expression and mRNA levels were significantly increased by high K⁺ diet (5%) and decreased by dietary K⁺ restriction (0.003%). In contrast, variations in Na⁺ regimen had no apparent effect on TRPV4 expression and mRNA levels. Regulation of TRPV4 protein expression by K⁺ diet was independent of …