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Multi-Level Effects Of Low Dose Rate Ionizing Radiation On Southern Toad, Anaxyrus [Bufo] Terrestris, Karolina Stark, David E. Scott, Olga Tsyusko, Daniel P. Coughlin, Thomas G. Hinton

Plant and Soil Sciences Faculty Publications

Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development -embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³⁷Cs at 0.13, 2.4, 21, and 222 mGy d^-1, resulting in total doses up to 15.8 …

Plasma Tnf-Α And Soluble Tnf Receptor Levels After Doxorubicin With Or Without Co-Administration Of Mesna-A Randomized, Cross-Over Clinical Study, John Hayslip, Emily Van Meter Dressler, Heidi L. Weiss, Tammy J. Taylor, Mara D. Chambers, Teresa Noel, Sumitra Miriyala, Jeriel T. R. Keeney, Xiaojia Ren, Rukhsana Sultana, Mary Vore, D. Allan Butterfield, Daret St. Clair, Jeffrey A. Moscow

Markey Cancer Center Faculty Publications

PURPOSE: Chemotherapy-induced cognitive impairment (CICI) is a common sequelae of cancer therapy. Recent preclinical observations have suggested that CICI can be mediated by chemotherapy-induced plasma protein oxidation, which triggers TNF-α mediated CNS damage. This study evaluated sodium-2-mercaptoethane sulfonate (Mesna) co-administration with doxorubicin to reduce doxorubicin-induced plasma protein oxidation and resultant cascade of TNF-α, soluble TNF receptor levels and related cytokines.

METHODS: Thirty-two evaluable patients were randomized using a crossover design to receive mesna or saline in either the first or second cycle of doxorubicin in the context of a standard chemotherapy regimen for either non-Hodgkin lymphoma or breast …

Closed Head Injury In An Age-Related Alzheimer Mouse Model Leads To An Altered Neuroinflammatory Response And Persistent Cognitive Impairment, Scott J. Webster, Linda J. Van Eldik, D. Martin Watterson, Adam D. Bachstetter

Sanders-Brown Center on Aging Faculty Publications

Epidemiological studies have associated increased risk of Alzheimer's disease (AD)-related clinical symptoms with a medical history of head injury. Currently, little is known about pathophysiology mechanisms linked to this association. Persistent neuroinflammation is one outcome observed in patients after a single head injury. Neuroinflammation is also present early in relevant brain regions during AD pathology progression. In addition, previous mechanistic studies in animal models link neuroinflammation as a contributor to neuropathology and cognitive impairment in traumatic brain injury (TBI) or AD-related models. Therefore, we explored the potential interplay of neuroinflammatory responses in TBI and AD by analysis of the temporal …

Mechanism-Based Combination Treatment Dramatically Increases Therapeutic Efficacy In Murine Globoid Cell Leukodystrophy, Jacqueline A. Hawkins-Salsbury, Lauren Shea, Xuntian Jiang, Daniel A. Hunter, A Miguel Guzman, Adarsh S. Reddy, Elizabeth Y. Qin, Yedda Li, Steven J. Gray, Daniel S. Ory, Mark S. Sands

Open Access Publications

Globoid cell leukodystrophy (GLD, Krabbe disease) is a lysosomal storage disease (LSD) caused by a deficiency in galactocerebrosidase (GALC) activity. In the absence of GALC activity, the cytotoxic lipid, galactosylsphingosine (psychosine), accumulates in the CNS and peripheral nervous system. Oligodendrocytes and Schwann cells are particularly sensitive to psychosine, thus leading to a demyelinating phenotype. Although hematopoietic stem-cell transplantation provides modest benefit in both presymptomatic children and the murine model (Twitcher), there is no cure for GLD. In addition, GLD has been relatively refractory to virtually every experimental therapy attempted. Here, Twitcher mice were simultaneously treated with CNS-directed gene therapy, substrate …

Targeting Human Central Nervous System Protein Kinases: An Isoform Selective P38Αmapk Inhibitor That Attenuates Disease Progression In Alzheimer's Disease Mouse Models, Saktimayee M. Roy, Valerie L. Grum-Tokars, James P. Schavocky, Faisal Saeed, Agnieszka Staniszewski, Andrew F. Teich, Ottavio Arancio, Adam D. Bachstetter, Scott J. Webster, Linda J. Van Eldik, George Minasov, Wayne F. Anderson, Jeffrey C. Pelletier, D. Martin Watterson

Spinal Cord and Brain Injury Research Center Faculty Publications

The first kinase inhibitor drug approval in 2001 initiated a remarkable decade of tyrosine kinase inhibitor drugs for oncology indications, but a void exists for serine/threonine protein kinase inhibitor drugs and central nervous system indications. Stress kinases are of special interest in neurological and neuropsychiatric disorders due to their involvement in synaptic dysfunction and complex disease susceptibility. Clinical and preclinical evidence implicates the stress related kinase p38αMAPK as a potential neurotherapeutic target, but isoform selective p38αMAPK inhibitor candidates are lacking and the mixed kinase inhibitor drugs that are promising in peripheral tissue disease indications have limitations for neurologic indications. Therefore, …

One-Step Generation Of Multiple Transgenic Mouse Lines Using An Improved Pronuclear Injection-Based Targeted Transgenesis (I-Pitt)., Masato Ohtsuka, Hiromi Miura, Keiji Mochida, Michiko Hirose, Ayumi Hasegawa, Atsuo Ogura, Ryuta Mizutani, Minoru Kimura, Ayako Isotani, Masahito Ikawa, Masahiro Sato, Channabasavaiah B. Gurumurthy

Journal Articles: Genetics, Cell Biology & Anatomy

BACKGROUND: The pronuclear injection (PI) is the simplest and widely used method to generate transgenic (Tg) mice. Unfortunately, PI-based Tg mice show uncertain transgene expression due to random transgene insertion in the genome, usually with multiple copies. Thus, typically at least three or more Tg lines are produced by injecting over 200 zygotes and the best line/s among them are selected through laborious screening steps. Recently, we developed technologies using Cre-loxP system that allow targeted insertion of single-copy transgene into a predetermined locus through PI. We termed the method as PI-based Targeted Transgenesis (PITT). A similar method using PhiC31-attP/B system …

Hco3(-)-Independent Ph Regulation In Astrocytes In Situ Is Dominated By V-Atpase., Daniel Bloch Hansen, Nestor Garrido-Comas, Mike Salter, Robert Fern

More Faculty of Health Research

The mechanisms of HCO3(-)-independent intracellular pH (pHi) regulation were examined in fibrous astrocytes within isolated neonatal rat optic nerve (RON) and in cultured cortical astrocytes. In agreement with previous studies, resting pHi in cultured astrocytes was 6.82 ± 0.06 and inhibition of the V-ATPase H(+) pump by Cl(-) removal or via the selective inhibitor bafilomycin had only a small effect upon resting pHi and recovery following an acid load. In contrast, resting pHi in RON astrocytes was 7.10 ± 0.04, significantly less acidic than that in cultured cells (p < 0.001), and responded to inhibition of V-ATPase with profound acidification to the 6.3-6.5 range. Fluorescent immuno-staining and immuno-gold labeling confirmed the presence V-ATPase in the cell membrane of RON astrocyte processes and somata. Using ammonia pulse recovery, pHi recovery in RON astrocyte was achieved largely via V-ATPase with sodium-proton exchange (NHE) playing a minor role. The findings indicate that astrocytes in a whole-mount preparation such as the optic nerve rely to a greater degree upon V-ATPase for HCO3(-)-independent pHi regulation than do cultured astrocytes, with important functional consequences for the regulation of pH in the CNS.

Enhanced Nmda Receptor-Mediated Modulation Of Excitatory Neurotransmission In The Dorsal Vagal Complex Of Streptozotocin-Treated, Chronically Hyperglycemic Mice, Eva C. Bach, Katalin Cs. Halmos, Bret N. Smith

Physiology Faculty Publications

A variety of metabolic disorders, including complications experienced by diabetic patients, have been linked to altered neural activity in the dorsal vagal complex. This study tested the hypothesis that augmentation of N-Methyl-D-Aspartate (NMDA) receptor-mediated responses in the vagal complex contributes to increased glutamate release in the dorsal motor nucleus of the vagus nerve (DMV) in mice with streptozotocin-induced chronic hyperglycemia (i.e., hyperglycemic mice), a model of type 1 diabetes. Antagonism of NMDA receptors with AP-5 (100 μM) suppressed sEPSC frequency in vagal motor neurons recorded in vitro, confirming that constitutively active NMDA receptors regulate glutamate release in the DMV. There …

Individual Quality And Personality: Bolder Males Are Less Fecund In The Hermit Crab Pagurus Bernhardus., Danielle Bridger, Simon J. Bonner, Mark Briffa

School of Biological and Marine Sciences

One explanation for animal personality is that different behavioural types derive from different life-history strategies. Highly productive individuals, with high growth rates and high fecundity, are assumed to live life at a fast pace showing high levels of boldness and risk taking, compared with less productive individuals. Here, we investigate among-individual differences in mean boldness (the inverse of the latency to recover from a startling stimulus) and in the consistency of boldness, in male hermit crabs in relation to two aspects of life-history investment. We assessed aerobic scope by measuring the concentration of the respiratory pigment haemocyanin, and we assessed …

Mitochondria-Associated Micrornas In Rat Hippocampus Following Traumatic Brain Injury, Wang-Xia Wang, Nishant P. Visavadiya, Jignesh D. Pandya, Peter T. Nelson, Patrick G. Sullivan, Joe E. Springer

Sanders-Brown Center on Aging Faculty Publications

Traumatic brain injury (TBI) is a major cause of death and disability. However, the molecular events contributing to the pathogenesis are not well understood. Mitochondria serve as the powerhouse of cells, respond to cellular demands and stressors, and play an essential role in cell signaling, differentiation, and survival. There is clear evidence of compromised mitochondrial function following TBI; however, the underlying mechanisms and consequences are not clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally, and function as important mediators of neuronal development, synaptic plasticity, and neurodegeneration. Several miRNAs show altered expression following TBI; however, the …

Pharmacologically Distinct Nicotinic Acetylcholine Receptors Drive Efferent-Mediated Excitation In Calyx-Bearing Vestibular Afferents, J. Chris Holt, Kevin Kewin, Paivi M. Jordan, Peter Cameron, Marcin Klapczynski, J. Michael Mcintosh, Peter A. Crooks, Linda P. Dwoskin, Anna Lysakowski

Pharmaceutical Sciences Faculty Publications

Electrical stimulation of vestibular efferent neurons rapidly excites the resting discharge of calyx/dimorphic (CD) afferents. In turtle, this excitation arises when acetylcholine (ACh), released from efferent terminals, directly depolarizes calyceal endings by activating nicotinic ACh receptors (nAChRs). Although molecular biological data from the peripheral vestibular system implicate most of the known nAChR subunits, specific information about those contributing to efferent-mediated excitation of CD afferents is lacking. We sought to identify the nAChR subunits that underlie the rapid excitation of CD afferents and whether they differ from α9α10 nAChRs on type II hair cells that drive efferent-mediated inhibition in adjacent bouton …

Novel Actions Of Next-Generation Taxanes Benefit Advanced Stages Of Prostate Cancer., Renée De Leeuw, Lisa D. Berman-Booty, Matthew J. Schiewer, Stephen J Ciment, Robert Den, Adam P. Dicker, William Kelly, Edouard J. Trabulsi, Costas D. Lallas, Leonard G. Gomella, Karen E. Knudsen

Department of Cancer Biology Faculty Papers

PURPOSE: To improve the outcomes of patients with castration-resistant prostate cancer (CRPC), there is an urgent need for more effective therapies and approaches that individualize specific treatments for patients with CRPC. These studies compared the novel taxane cabazitaxel with the previous generation docetaxel, and aimed to determine which tumors are most likely to respond.

EXPERIMENTAL DESIGN: Cabazitaxel and docetaxel were compared via in vitro modeling to determine the molecular mechanism, biochemical and cell biologic impact, and cell proliferation, which was further assessed ex vivo in human tumor explants. Isogenic pairs of RB knockdown and control cells were interrogated in vitro …

Designer Receptors Enhance Memory In A Mouse Model Of Down Syndrome, Ashley M. Fortress, Eric D. Hamlett, Elena M. Vazey, Gary Aston-Jones, Wayne A. Cass, Heather A. Boger, Ann-Charlotte E. Granholm

Neuroscience Faculty Publications

Designer receptors exclusively activated by designer drugs (DREADDs) are novel and powerful tools to investigate discrete neuronal populations in the brain. We have used DREADDs to stimulate degenerating neurons in a Down syndrome (DS) model, Ts65Dn mice. Individuals with DS develop Alzheimer's disease (AD) neuropathology and have elevated risk for dementia starting in their 30s and 40s. Individuals with DS often exhibit working memory deficits coupled with degeneration of the locus coeruleus (LC) norepinephrine (NE) neurons. It is thought that LC degeneration precedes other AD-related neuronal loss, and LC noradrenergic integrity is important for executive function, working memory, and attention. …

Zhx2 Enhances The Cytotoxicity Of Chemotherapeutic Drugs In Liver Tumor Cells By Repressing Mdr1 Via Interfering With Nf-Ya, Hongxin Ma, Xuetian Yue, Lifen Gao, Xiaohong Liang, Wenjiang Yan, Zhenyu Zhang, Haixia Shan, Hualin Zhang, Brett T. Spear, Chunhong Ma

Microbiology, Immunology, and Molecular Genetics Faculty Publications

We previously reported the tumor suppressor function of Zinc-fingers and homeoboxes 2 (ZHX2) in hepatocellular carcinoma (HCC). Other studies indicate the association of increased ZHX2 expression with improved response to high dose chemotherapy in multiple myeloma. Here, we aim to test whether increased ZHX2 levels in HCC cells repress multidrug resistance 1(MDR1) expression resulting in increased sensitivity to chemotherapeutic drugs. We showed evidence that increased ZHX2 levels correlated with reduced MDR1 expression and enhanced the cytotoxicity of CDDP and ADM in different HCC cell lines. Consistently, elevated ZHX2 significantly reduced ADM efflux in HepG2 cells and greatly increased the CDDP-mediated …

Space Use, Daily Movements, And Roosting Behavior Of Male Wild Turkeys During Spring In Louisiana And Texas, John T. Gross, Andrew R. Little, Bret A. Collier, Michael J. Chamberlain

School of Natural Resources: Faculty Publications

Because wild turkeys (Meleagris gallopavo) are an important game species and turkey hunter numbers are increasing, the need for better information on how turkeys use their environment is critical. With the recent advent of GPS technology suitable for use on wild turkeys, we are now able to collect data on a scale not previously possible. We used backpack style GPS units to detail home range and core area sizes, daily movement distances, and roosting characteristics of male Eastern (M. g. silvestris) and Rio Grande (M. g. intermedia) wild turkeys in Louisiana and Texas. Mean …

Intracellular Cd24 Disrupts The Arf-Npm Interaction And Enables Mutational And Viral Oncogene-Mediated P53 Inactivation., Lizhong Wang, Runhua Liu, Peiying Ye, Chunshu Wong, Guo-Yun Chen, Penghui Zhou, +11 Additional Authors

Pediatrics Faculty Publications

CD24 is overexpressed in nearly 70% human cancers, whereas TP53 is the most frequently mutated tumour-suppressor gene that functions in a context-dependent manner. Here we show that both targeted mutation and short hairpin RNA (shRNA) silencing of CD24 retard the growth, progression and metastasis of prostate cancer. CD24 competitively inhibits ARF binding to NPM, resulting in decreased ARF, increase MDM2 and decrease levels of p53 and the p53 target p21/CDKN1A. CD24 silencing prevents functional inactivation of p53 by both somatic mutation and viral oncogenes, including the SV40 large T antigen and human papilloma virus 16 E6-antigen. In support of the …

Comparison Of Individual And Pooled Urine Samples For Estimating The Presence And Intensity Of Schistosoma Haematobium Infections At The Population Level, Abraham Degarege, Berhanu Erko, Zeleke Mekonnen, Mengistu Legesse, Yohannes Negash, Jozef Vercruysse, Bruno Levecke

Journal Articles: Epidemiology

BACKGROUND: There is a lack of cost-effective diagnostic strategies to evaluate whether mass drug administration (MDA) programmes to control Schistosoma haematobium progress as anticipated. The purpose of this study is to provide a proof-of-principle for examination of pooled urine samples as a strategy for rapid assessment of presence and intensity of Schistosoma haematobium infections at the population level.

METHODS: A total of 640 urine samples were collected from 520 school-aged children (520 at baseline and 120 at follow-up) during a clinical trial that was designed to assess the efficacy of praziquantel against Schistosoma haematobium infections in Ethiopia. Individual and pooled …

Clinical Presentation Of Patients With Ebola Virus Disease In Conakry, Guinea, Elhadj Ibrahima Bah, Marie-Claire Lamah, Tom Fletcher, Shevin T. Jacob, David Brett-Major, Amadou Alpha Sall, Nahoko Shindo, William A. Fischer, Francois Lamontagne, Sow Mamadou Saliou, Daniel G. Bausch, Barry Moumié, Tim Jagatic, Armand Sprecher, James V. Lawler, Thierry Mayet, Frederique A. Jacquerioz, María F. Méndez Baggi, Constanza Vallenas, Christophe Clement, Simon Mardel, Ousmane Faye, Oumar Faye, Baré Soropogui, Nfaly Magassouba, Lamine Koivogui, Ruxandra Pinto, Robert A. Fowler

Journal Articles: Epidemiology

BACKGROUND: In March 2014, the World Health Organization was notified of an outbreak of Zaire ebolavirus in a remote area of Guinea. The outbreak then spread to the capital, Conakry, and to neighboring countries and has subsequently become the largest epidemic of Ebola virus disease (EVD) to date.

METHODS: From March 25 to April 26, 2014, we performed a study of all patients with laboratory-confirmed EVD in Conakry. Mortality was the primary outcome. Secondary outcomes included patient characteristics, complications, treatments, and comparisons between survivors and nonsurvivors.

RESULTS: Of 80 patients who presented with symptoms, 37 had laboratory-confirmed EVD. Among confirmed …

The Effect Of Statins On Blood Gene Expression In Copd, Ma'en Obeidat, Nick Fishbane, Yunlong Nie, Virginia Chen, Zsuzsanna Hollander, Scottj Tebbutt, Yohan Bossé, Raymond T. Ng, Bruce E. Miller, Bruce Mcmanus, Stephen I. Rennard, Peter D. Paré, Don D. Sin

Journal Articles: Pulmonary & Critical Care Med

BACKGROUND: COPD is currently the fourth leading cause of death worldwide. Statins are lipid lowering agents with documented cardiovascular benefits. Observational studies have shown that statins may have a beneficial role in COPD. The impact of statins on blood gene expression from COPD patients is largely unknown.

OBJECTIVE: Identify blood gene signature associated with statin use in COPD patients, and the pathways underpinning this signature that could explain any potential benefits in COPD.

METHODS: Whole blood gene expression was measured on 168 statin users and 451 non-users from the ECLIPSE study using the Affymetrix Human Gene 1.1 ST microarray chips. …

Assessment Of Artificial Mirna Architectures For Higher Knockdown Efficiencies Without The Undesired Effects In Mice., Hiromi Miura, Hidetoshi Inoko, Masafumi Tanaka, Hirofumi Nakaoka, Minoru Kimura, Channabasavaiah B. Gurumurthy, Masahiro Sato, Masato Ohtsuka

Journal Articles: Genetics, Cell Biology & Anatomy

RNAi-based strategies have been used for hypomorphic analyses. However, there are technical challenges to achieve robust, reproducible knockdown effect. Here we examined the artificial microRNA (amiRNA) architectures that could provide higher knockdown efficiencies. Using transient and stable transfection assays in cells, we found that simple amiRNA-expression cassettes, that did not contain a marker gene (-MG), displayed higher amiRNA expression and more efficient knockdown than those that contained a marker gene (+MG). Further, we tested this phenomenon in vivo, by analyzing amiRNA-expressing mice that were produced by the pronuclear injection-based targeted transgenesis (PITT) method. While we observed significant silencing of the …

Mk591, A Second Generation Leukotriene Biosynthesis Inhibitor, Prevents Invasion And Induces Apoptosis In The Bone-Invading C4-2b Human Prostate Cancer Cells: Implications For The Treatment Of Castration-Resistant, Bone-Metastatic Prostate Cancer, Sivalokanathan Sarveswaran, Ritisha Ghosh, Shravan Morisetty, Jagadananda Ghosh

Urology Articles

Castration-resistant prostate cancer (CRPC) is a major clinical challenge for which no cure is currently available primarily because of the lack of proper understanding about appropriate molecular target(s). Previously we observed that inhibition of 5-lipoxygenase (5-Lox) activity induces apoptosis in some types of prostate cancer cells, suggesting an important role of 5-Lox in the viability of prostate cancer cells. However, nothing is known about the role of 5-Lox in the survival of castration-resistant, metastatic prostate cancer cells. Thus, we tested the effects of MK591, a second-generation, specific inhibitor of 5-Lox activity, on the viability and metastatic characteristics of CRPC cells. …

Expression Of Enteropathogenic Escherichia Coli Map Is Significantly Different Than That Of Other Type Iii Secreted Effectors In Vivo., Mai Nguyen, Jason Rizvi, Gail Hecht

Department of Medicine Faculty Papers

The enteropathogenic Escherichia coli (EPEC) locus of enterocyte effacement (LEE)-encoded effectors EspF and Map are multifunctional and have an impact on the tight junction barrier while the non-LEE-encoded proteins NleH1 and NleH2 possess significant anti-inflammatory activity. In order to address the temporal expression of these important genes in vivo, their promoters were cloned upstream of the luxCDABE operon, and luciferase expression was measured in EPEC-infected mice by bioluminescence using an in vivo imaging system (IVIS). Bioluminescent images of living mice, of excised whole intestines, and of whole intestines longitudinally opened and washed were assessed. The majority of bioluminescent bacteria localized …

Age-Related Factors Influencing The Occurrence Of Undernutrition In Northeastern Ethiopia, Abraham Degarege, Elifaged Hailemeskel, Berhanu Erko

Journal Articles: Epidemiology

BACKGROUND: Undernutrition is a major public health problem on the globe particularly in the developing regions. The objective of the current study was to assess the prevalence of undernutrition in different age groups and examine the relationship of the disease to parasitic and socioeconomic factors among communities in Harbu Town, northeastern Ethiopia.

METHODS: Stool samples of the study participants were examined for intestinal helminth infections using the Kato-Katz method. Blood specimens were diagnosed for Plasmodium infection using CareStartTM Malaria Pf/Pv Combo test. The blood type was determined from blood samples using antisera A and antisera B. In addition, the height …

Posture Affects How Robots And Infants Map Words To Objects., Af Morse, Vl Benitez, T Belpaeme, A Cangelosi, Lb Smith

School of Engineering, Computing and Mathematics

For infants, the first problem in learning a word is to map the word to its referent; a second problem is to remember that mapping when the word and/or referent are again encountered. Recent infant studies suggest that spatial location plays a key role in how infants solve both problems. Here we provide a new theoretical model and new empirical evidence on how the body - and its momentary posture - may be central to these processes. The present study uses a name-object mapping task in which names are either encountered in the absence of their target (experiments 1-3, 6 …

Renal And Hematological Effects Of Clcf-1, A B-Cell-Stimulating Cytokine Of The Il-6 Family., Virginia J. Savin, Mukut Sharma, Jianping Zhou, David Gennochi, Timothy Fields, Ram Sharma, Ellen T. Mccarthy, Tarak Srivastava, Jos Domen, Aurélie Tormo, Jean-François Gauchat

Manuscripts, Articles, Book Chapters and Other Papers

CLCF-1 is a cytokine known for B-cell stimulation and for neurotrophic properties. We have identified CLCF-1 as a potential injurious factor in the human renal disease focal segmental glomerulosclerosis (FSGS). We investigated its effects on renal cells and renal function in in vitro and in vivo studies. Methods include measurement of the effect of CLCF-1 on phosphorylation of target molecules of the JAK/STAT pathway, on cytoskeleton and cell morphology in cultured podocytes, on albumin permeability of isolated rat glomeruli, and on tissue phosphorylation and urine albumin after acute or chronic CLCF-1 injection. In addition, cell sorting was performed to determine …

Follow-Up Plasma Apolipoprotein E Levels In The Australian Imaging, Biomarkers And Lifestyle Flagship Study Of Ageing (Aibl) Cohort, Veer B. Gupta, V.B, Andrea C. Wilson, Samantha Burnham, Eugene Hone, Steve Pedrini, Simon M. Laws, Wei L.F. Lim, Alan Rembach, Stephanie Rainey-Smith, David Ames, Lynne Cobiac, S L. Macaulay, Colin L. Masters, Christopher C. Rowe, Ashley I. Bush, Ralph Martins, Aibl Research Group

Research outputs 2014 to 2021

Introduction: Alzheimer's disease (AD) is a growing socioeconomic problem worldwide. Early diagnosis and prevention of this devastating disease have become a research priority. Consequently, the identification of clinically significant and sensitive blood biomarkers for its early detection is very important. Apolipoprotein E (APOE) is a well-known and established genetic risk factor for late-onset AD; however, the impact of the protein level on AD risk is unclear. We assessed the utility of plasma ApoE protein as a potential biomarker of AD in the large, well-characterised Australian Imaging, Biomarkers and Lifestyle Study of Ageing (AIBL) cohort. Methods: Total plasma ApoE levels were …

Amyloid-Related Memory Decline In Preclinical Alzheimer's Disease In Dependent On Apoe Ε4 And Is Detectable Over 18-Months, Christine Thai, Yen Ying Lim, Victor L. Villemagne, Simon Laws, David Ames, Kathryn A. Ellis, Stephanie Rainey-Smith, Ralph Martins, Colin L. Masters, Christopher C. Rowe, Paul Maruff, Australian Imaging, Biomarkers And Lifestyle (Aibl) Research Group

Research outputs 2014 to 2021

High levels of β-amyloid (Aβ) in the brain and carriage of the APOE ε4 allele have each been linked to cognitive impairment in cognitively normal (CN) older adults. The aim of this study was to investigate the relationship between cerebral Aβ level, APOE ε4 carrier status, and cognitive decline over 18 monthes, in 317 cognitively healthy (CN) older adults (47% males, 52.4% females) aged between 60 and 89 years (Mean = 69.9, SC = 6.8). Cognition was assessed using the Cogstate Brief Battery (CBB) and the California Verbal Learning Test, Second Edition (CVLT-II). Planned comparisons indicated that CN older adults …

Effects Of Ambient Coarse, Fine, And Ultrafine Particles And Their Biological Constituents On Systemic Biomarkers: A Controlled Human Exposure Study, Ling Liu, Bruce Urch, Raymond Poon, Mieczyslaw Szyszkowicz, Mary Speck, Diane R. Gold, Amanda J. Wheeler, James A. Scott, Jeffrey R. Brook, Peter S. Thorne, Frances S. Silverman

Research outputs 2014 to 2021

Background: Ambient coarse, fine, and ultrafine particles have been associated with mortality and morbidity. Few studies have compared how various particle size fractions affect systemic biomarkers. Objectives: We examined changes of blood and urinary biomarkers following exposures to three particle sizes. Methods: Fifty healthy nonsmoking volunteers, mean age of 28 years, were exposed to coarse (2.5–10 μm; mean, 213 μg/m3) and fine (0.15–2.5 μm; mean, 238 μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (< 0.3 μm; mean, 136 μg/m3) and filtered medical air. Exposures lasted 130 min, separated by ≥ 2 weeks. Blood/urine samples were collected preexposure and 1 hr and 21 hr postexposure to determine blood interleukin-6 and C-reactive protein (inflammation), endothelin-1 and vascular endothelial growth factor (VEGF; vascular mediators), and malondialdehyde (lipid peroxidation); as well as urinary VEGF, 8-hydroxy-deoxy-guanosine (DNA oxidation), and malondialdehyde. Mixed-model regressions assessed pre- and postexposure differences. results: One hour postexposure, for every 100-μg/m3 increase, coarse CAP was associated with increased blood VEGF (2.41 pg/mL; 95% CI: 0.41, 4.40) in models adjusted for O3, fine CAP with increased urinary malondialdehyde in single- (0.31 nmol/mg creatinine; 95% CI: 0.02, 0.60) and two-pollutant models, and ultrafine CAP with increased urinary 8-hydroxydeoxyguanosine in single- (0.69 ng/mg creatinine; 95% CI: 0.09, 1.29) and two-pollutant models, lasting < 21 hr. Endotoxin was significantly associated with biomarker changes similar to those found with CAPs. conclusions: Ambient particles with various sizes/constituents may influence systemic biomarkers differently. Endotoxin in ambient particles may contribute to vascular mediator changes and oxidative stress.

Outcome Predictability Biases Learning., Oren Griffiths, Chris J. Mitchell, Anna Bethmont, Peter F. Lovibond

School of Psychology

Much of contemporary associative learning research is focused on understanding how and when the associative history of cues affects later learning about those cues. Very little work has investigated the effects of the associative history of outcomes on human learning. Three experiments extended the "learned irrelevance" paradigm from the animal conditioning literature to examine the influence of an outcome's prior predictability on subsequent learning of relationships between cues and that outcome. All 3 experiments found evidence for the idea that learning is biased by the prior predictability of the outcome. Previously predictable outcomes were readily associated with novel predictive cues, …

Smooth-Muscle Bmal1 Participates In Blood Pressure Circadian Rhythm Regulation, Zhongwen Xie, Wen Su, Shu Liu, Guogang Zhao, Karyn Esser, Elizabeth A. Schroder, Mellani Lefta, Harald M. Stauss, Zhenheng Guo, Ming Cui Gong

Physiology Faculty Publications

As the central pacemaker, the suprachiasmatic nucleus (SCN) has long been considered the primary regulator of blood pressure circadian rhythm; however, this dogma has been challenged by the discovery that each of the clock genes present in the SCN is also expressed and functions in peripheral tissues. The involvement and contribution of these peripheral clock genes in the circadian rhythm of blood pressure remains uncertain. Here, we demonstrate that selective deletion of the circadian clock transcriptional activator aryl hydrocarbon receptor nuclear translocator-like (Bmal1) from smooth muscle, but not from cardiomyocytes, compromised blood pressure circadian rhythm and decreased blood …