Pharmacology, Toxicology and Environmental Health Commons^™

Effects Of Anandamide Administration On Components Of Reward Processing, Howard C. Cromwell

Howard Casey Cromwell

Pharmacological And Antihyperalgesic Properties Of The Novel Α2/3 Preferring Gabaa Receptor Ligand Mp-Iii-024., Bradford D. Fischer, Raymond J. Schlitt, Bryan Z. Hamade, Sabah Rehman, Margot Ernst, Michael M. Poe, Guanguan Li, Revathi Kodali, Leggy A. Arnold, James M. Cook

Bradford Fischer

Perampanel, Michael A. Rogawski

Michael A. Rogawski

No abstract provided.

An Analysis Of The Use Of Animal Models In Predicting Human Toxicology And Drug Safety, Jarrod Bailey, Michelle Thew, Michael Balls

Jarrod Bailey, PhD

Animal use continues to be central to preclinical drug development, in spite of a lack of its demonstrable validity. The current nadir of new drug approvals and the drying-up of pipelines may be a direct consequence of this. To estimate the evidential weight given by animal data to the probability that a new drug may be toxic to humans, we have calculated Likelihood Ratios (LRs) for an extensive data set of 2,366 drugs, for which both animal and human data are available, including tissue-level effects and MedDRA Level 1–4 biomedical observations. This was done for three preclinical species (rat, mouse …

The Current Scientific And Legal Status Of Alternative Methods To The Ld50 Test For Botulinum Neurotoxin Potency Testing, Sarah Adler, Gerd Bicker, Hans Bigalke, Christopher Bishop, Jörg Blümel, Dirk Dressler, Joan Fitzgerald, Frank Gessler, Heide Heuschen, Birgit Kegel, Andreas Luch, Catherine Milne, Andrew Pickett, Heidemarie Ratsch, Irmela Ruhdel, Dorothea Sesardic, Martin Stephens, Gerhard Stiens, Peter D. Thornton, René Thürmer, Martin Vey, Horst Spielmann, Barbara Grune, Manfred Liebsch

Martin Stephens, PhD

No abstract provided.

Bringing Toxicology Into The 21st Century: A Global Call To Action, Troy Seidle, Martin Stephens

Martin Stephens, PhD

Conventional toxicological testing methods are often decades old, costly and low-throughput, with questionable relevance to the human condition. Several of these factors have contributed to a backlog of chemicals that have been inadequately assessed for toxicity. Some authorities have responded to this challenge by implementing large-scale testing programmes. Others have concluded that a paradigm shift in toxicology is warranted. One such call came in 2007 from the United States National Research Council (NRC), which articulated a vision of ‘‘21st century toxicology” based predominantly on non-animal techniques. Potential advantages of such an approach include the capacity to examine a far greater …

Pesticide Policy And Farmworker Health, Joan D. Flocks

Joan D. Flocks

Although data on the carcinogenicity of agricultural pesticides are still being generated and are thus incomplete, research such as the Agricultural Health Study indicates that populations with increased, regular exposure to pesticides have high rates of a variety of cancers (National Institutes of Health & Environmental Protection Agency 2008). Policies that regulate toxins such as pesticides are envisioned by the public to be empirical and objective, but toxins are socially produced and their regulation is just as often based on political and economic factors as it is on science (Luke 2000). This does not bode well for farm- workers who …

Β-Thujaplicin: A Soil Antifungal, Dennis J. Baumgardner

Dennis J. Baumgardner, MD

Background: β-thujaplicin (β-Th), also known as hinokitiol, naturally occurs in cedar mulch, is found in personal care products and has in vitro antitumor activities. It is antibacterial and antifungal, but has not been tested on soil. Scedosporium apiospermum (Sce) is an emerging “extremophile” fungal pathogen found in built outdoor environments. Purpose: Pilot β-Th as “natural” soil antimicrobial or for isolation of extremophiles, and to explore β-Th resistance as selective advantage to Sce in mulched landscape. Methods: A variety of outdoor and indoor environments were used for 2 sets of 24 paired soil samples. Soil/H20 slurry (0.1 ml) was spread on …

The Shellfish Corner -- Water Quality And Culture Of Shellfish In Prohibited Waters, Michael A. Rice

Michael A Rice

Structural Basis For Mutation-Induced Destabilization Of Profilin 1 In Als, Sivakumar Boopathy, Tania Silvas, Maeve Tischbein, Silvia Jansen, Shivender Shandilya, Jill Zitzewitz, John Landers, Bruce Goode, Celia Schiffer, Daryl Bosco

Celia A. Schiffer

Mutations in profilin 1 (PFN1) are associated with amyotrophic lateral sclerosis (ALS); however, the pathological mechanism of PFN1 in this fatal disease is unknown. We demonstrate that ALS-linked mutations severely destabilize the native conformation of PFN1 in vitro and cause accelerated turnover of the PFN1 protein in cells. This mutation-induced destabilization can account for the high propensity of ALS-linked variants to aggregate and also provides rationale for their reported loss-of-function phenotypes in cell-based assays. The source of this destabilization is illuminated by the X-ray crystal structures of several PFN1 proteins, revealing an expanded cavity near the protein core of the …

Antagonism Of Triazolam Self-Administration In Rhesus Monkeys Responding Under A Progressive-Ratio Schedule: In Vivo Apparent Pa2 Analysis, Bradford D. Fischer Phd, Donna M. Platt, Sundari K. Rallapalli, Ojas A. Namjoshi, James M. Cook, James K. Rowlett

Bradford Fischer

No abstract provided.

Prepubertal Organochlorine Pesticide Concentrations And Age Of Pubertal Onset Among Russian Boys, Thuy Lam, Paige Williams, Mary Lee, Susan Korrick, Linda Birnbaum, Jane Burns, Oleg Sergeyev, Boris Revich, Larisa Altshul, Donald Patterson, Wayman Turner, Russ Hauser

Mary M. Lee

BACKGROUND: In animal studies, organochlorine pesticide (OCP) exposure alters pubertal development; however, epidemiological data are limited and inconsistent. OBJECTIVE: To evaluate the associations of serum OCP concentrations [hexachlorobenzene (HCB), beta-hexachlorocyclohexane (beta-HCH), and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE)] with male pubertal onset. METHODS: In Chapaevsk, Russia, a town environmentally contaminated with OCPs, 350 8-9 year old boys with measured OCPs were enrolled during 2003-2005 and were followed annually for eight years. We evaluated three measures of pubertal onset: testicular volume (TV) > 3 mL in either testis, or stage 2 or greater for genitalia (G2+), or pubic hair (P2+). We used multivariable interval-censored models to …

Association Between Chlorinated Pesticides In The Serum Of Prepubertal Russian Boys And Longitudinal Biomarkers Of Metabolic Function, Jane Burns, Paige Williams, Susan Korrick, Russ Hauser, Oleg Sergeyev, Boris Revich, Thuy Lam, Mary Lee

Mary M. Lee

Organochlorine pesticides (OCPs) have been linked to adult metabolic disorders; however, few studies have examined these associations in childhood. We prospectively evaluated the associations of baseline serum OCPs (hexachlorobenzene, beta-hexachlorocyclohexane, and p,p'-dichlorodiphenyldichloroethylene) in Russian boys with subsequent repeated measurements of serum glucose, insulin, lipids, leptin, and calculated homeostatic model assessment of insulin resistance (IR). During 2003-2005, we enrolled 499 boys aged 8-9 years in a prospective cohort; 318 had baseline serum OCPs and serum biomarkers measured at ages 10-13 years. Multivariable generalized estimating equation and mediation regression models were used to examine associations and direct and indirect (via body mass …

Development Of A Novel Screening Strategy Designed To Discover A New Class Of Hiv Drugs, Nancy Cheng, Sook-Kyung Lee, P. Donover, Mel Reichman, Celia Schiffer, Emily Hull-Ryde, Ronald Swanstrom, William Janzen

Celia A. Schiffer

Current antiretroviral treatments target multiple pathways important for human immunodeficiency virus (HIV) multiplication, including viral entry, synthesis and integration of the DNA provirus, and the processing of viral polyprotein precursors. However, HIV is becoming increasingly resistant to these "combination therapies." Recent findings show that inhibition of HIV Gag protein cleavage into its two structural proteins, matrix (MA) and capsid (CA), has a devastating effect on viral production, revealing a potential new target class for HIV treatment. Unlike the widely used HIV protease inhibitors, this new class of inhibitor would target the substrate, not the protease enzyme itself. This approach offers …

Use Of Geographical Information Systems To Identify Counties In Georgia With High Risk For Childhood Lead Poisoning, R. Christopher Rustin, Christy Kuriatnyk, Byron Lobsinger, Simone Charles

R. Christopher Rustin

Examining The Regulatory Value Of Multi-Route Mammalian Acute Systemic Toxicity Studies, Troy Seidle, Pilar Prieto, Anna Bulgheroni

Troy Seidle, PhD

Regulatory information requirements for pesticides call for submission of acute systemic toxicity data for up to three different exposure routes (oral, dermal, inhalation) for both active ingredients and formulated products. Similar multi-route testing is required in the European Union and elsewhere for industrial chemicals. To determine the value of acute toxicity testing by more than one route, oral-dermal and oralinhalation concordances among regulatory classifications were examined for large data sets of chemicals and pesticide active ingredients. Across all sectors examined, oral acute toxicity classifications for pure active substances were more severe than those derived from dermal data in more than …

Can Acute Dermal Systemic Toxicity Tests Be Replaced With Oral Tests? A Comparison Of Route-Specific Systemic Toxicity And Hazard Classifications Under The Globally Harmonized System Of Classification And Labelling Of Chemicals (Ghs), Nigel P. Moore, David J. Andrew, Donald L. Bjerke, Stuart Creton, David Dreher, Thomas Holmes, Pilar Prieto, Troy Seidle, Tim G. Rowan

Troy Seidle, PhD

Acute systemic toxicity data (LD50 values) and hazard classifications derived in the rat following oral administration and dermal application have been analysed to examine whether or not orally-derived hazard classification or LD50 values can be used to determine dermal hazard classification. Comparing the oral and dermal classifications for 335 substances derived from oral and dermal LD50 values respectively revealed 17% concordance, and indicated that 7% of substances would be classified less severely while 76% would be classified more severely if oral classifications were applied directly to the dermal route. In contrast, applying the oral LD50 values within the dermal classification …

An Evaluation Of The Us High Production Volume (Hpv) Chemical-Testing Programme: A Study In (Ir)Relevance, Redundancy And Retro Thinking, Andrew Nicholson, Jessica Sandler, Troy Seidle

Troy Seidle, PhD

Under the US Environmental Protection Agency (EPA) High Production Volume (HPV) Challenge Programme, chemical companies have volunteered to conduct screening-level toxicity tests on approximately 2800 widely-used industrial chemicals. Participating companies are committed to providing available toxicity information to the EPA and presenting testing proposals for review by the EPA and posting on the EPA Web site as public information. People for the Ethical Treatment of Animals (PETA) and a coalition of animal protection organisations have reviewed all the test plans submitted by the participating chemical companies for compliance with the original HPV framework, as well as with animal welfare guidelines …

Cross-Sector Review Of Drivers And Available 3rs Approaches For Acute Systemic Toxicity Testing, Troy Seidle, Sally Robinson, Tom Holmes, Stuart Creton, Pilar Prieto, Julia Scheel, Magda Chlebus

Troy Seidle, PhD

Acute systemic toxicity studies are carried out in many sectors in which synthetic chemicals are manufactured or used and are among the most criticized of all toxicology tests on both scientific and ethical grounds. A review of the drivers for acute toxicity testing within the pharmaceutical industry led to a paradigm shift whereby in vivo acute toxicity data are no longer routinely required in advance of human clinical trials. Based on this experience, the following review was undertaken to identify (1) regulatory and scientific drivers for acute toxicity testing in other industrial sectors, (2) activities aimed at replacing, reducing, or …

The Development Of New Concepts For Assessing Reproductive Toxicity Applicable To Large Scale Toxicological Programmes, S. Bremer, C. Pellizzer, S. Hoffmann, T. Seidle, T. Hartung

Troy Seidle, PhD

Large scale toxicological testing programmes which are currently ongoing such as the new European chemical legislation REACH require the development of new integrated testing strategies rather than applying traditional testing schemes to thousands of chemicals. The current practice of requiring in vivo testing for every possible adverse effect endanger the success of these programmes due (i) to limited testing facilities and sufficient capacity of scientific/technical knowledge for reproductive toxicity; (ii) an unacceptable number of laboratory animals involved (iii) an intolerable number of chemicals classified as false positive.

A key aspect of the implementation of new testing strategies is the determination …

Bringing Toxicology Into The 21st Century: A Global Call To Action, Troy Seidle, Martin Stephens

Troy Seidle, PhD

Conventional toxicological testing methods are often decades old, costly and low-throughput, with questionable relevance to the human condition. Several of these factors have contributed to a backlog of chemicals that have been inadequately assessed for toxicity. Some authorities have responded to this challenge by implementing large-scale testing programmes. Others have concluded that a paradigm shift in toxicology is warranted. One such call came in 2007 from the United States National Research Council (NRC), which articulated a vision of ‘‘21st century toxicology” based predominantly on non-animal techniques. Potential advantages of such an approach include the capacity to examine a far greater …

A Modular One-Generation Reproduction Study As A Flexible Testing System For Regulatory Safety Assessment, Richard Vogel, Troy Seidle, Horst Spielmann

Troy Seidle, PhD

The European Union’s Registration, Evaluation and Authorisation of Chemicals (REACH) legislation mandates testing and evaluation of approximately 30,000 existing substances within a short period of time, beginning with the most widely used “high production volume” (HPV) chemicals. REACH testing requirements for the roughly 3000 HPV chemicals specify three separate tests for reproductive toxicity: two developmental toxicity studies on different animal species (OECD Test Guideline 414) and a two-generation reproduction toxicity study (OECD TG 416). These studies are highly costly in both economic and animal welfare terms. OECD TG 416 is a fertility study intended to evaluate reproductive performance of animals …

Considering A New Paradigm For Alzheimer’S Disease Research, Gillian R. Langley

Gill Langley, PhD

Using Alzheimer’s disease as a case study, this review argues that it might be time to consider a new paradigm in medical research and drug discovery. The existing framework is overly dependent on often unvalidated animal models, particularly transgenic mice. Translational success remains elusive and costly late-stage drug failure is common. The conventional paradigm tends to overlook species differences and assumes that animal-based findings are generally applicable to humans. Could pathways-based research using advanced human-specific models probed with new tools, including those of systems biology, take centre stage? The current transition in chemical toxicology to a 21st-century paradigm could be …

Role Of Gluk1 Kainate Receptors In Seizures, Epileptic Discharges, And Epileptogenesis, Brita Fritsch, Janine Reis, Maciej Gasior, Rafal M. Kaminski, Michael A. Rogawski

Michael A. Rogawski

Kainate receptors containing the GluK1 subunit have an impact on excitatory and inhibitory neurotransmission in brain regions, such as the amygdala and hippocampus, which are relevant to seizures and epilepsy. Here we used 2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl) propanoic acid (ATPA), a potent and selective agonist of kainate receptors that include the GluK1 subunit, in conjunction with mice deficient in GluK1 and GluK2 kainate receptor subunits to assess the role of GluK1 kainate receptors in provoking seizures and in kindling epileptogenesis. We found that systemic ATPA, acting specifically via GluK1 kainate receptors, causes locomotor arrest and forelimb extension (a unique behavioral characteristic of GluK1 …

Role Of Gluk1 Kainate Receptors In Seizures, Epileptic Discharges, And Epileptogenesis, Brita Fritsch, Janine Reis, Maciej Gasior, Rafal M. Kaminski, Michael A. Rogawski

Michael A. Rogawski

Kainate receptors containing the GluK1 subunit have an impact on excitatory and inhibitory neurotransmission in brain regions, such as the amygdala and hippocampus, which are relevant to seizures and epilepsy. Here we used 2-amino-3-(3-hydroxy-5-tert-butylisoxazol-4-yl) propanoic acid (ATPA), a potent and selective agonist of kainate receptors that include the GluK1 subunit, in conjunction with mice deficient in GluK1 and GluK2 kainate receptor subunits to assess the role of GluK1 kainate receptors in provoking seizures and in kindling epileptogenesis. We found that systemic ATPA, acting specifically via GluK1 kainate receptors, causes locomotor arrest and forelimb extension (a unique behavioral characteristic of GluK1 …

Imagining Possibilities For Healthy Appalachian Communities In An Emerging Postindustrial Landscape, Brian Hoey

Brian A. Hoey, Ph.D.

This paper explores how community might be re-imagined to promote incipient social and economic agendas born increasingly of broad-minded citizen initiatives within the Appalachian region aimed at what is generally understood as “development,” but of a form distinct from the prevailing models of a more industrial age. I would like to ask whether a city like Huntington, West Virginia can emerge as a progressive example of what we might term postindustrial, urban regeneration and perhaps what we might call community healing—specifically through grassroots movement now finding local governmental support in collective attempts to transform this place from one defined primarily …

Transmission Of Ranavirus Between Ectothermic Vertebrate Hosts, R Brenes, Matt J. Gray, T B. Waltzek, Rebecca P. Wilkes, Debra L. Miller

Debra L Miller

Transmission is an essential process that contributes to the survival of pathogens. Ranaviruses are known to infect different classes of lower vertebrates including amphibians, fishes and reptiles. Differences in the likelihood of infection among ectothermic vertebrate hosts could explain the successful yearlong persistence of ranaviruses in aquatic environments. The goal of this study was to determine if transmission of a Frog Virus 3 (FV3)-like ranavirus was possible among three species from different ectothermic vertebrate classes: Cope's gray treefrog (Hyla chrysoscelis) larvae, mosquito fish (Gambusia affinis), and red-eared slider (Trachemys scripta elegans). We housed individuals previously exposed to the FV3-like ranavirus …

Prolactin And Fmri Response To Skf38393 In The Baboon, Brad D. Miller, Lauren A. Marks, Jonathan M. Koller, Blake J. Newman, G Larry Bretthorst, Kevin J. Black

Kevin J. Black, MD

Background: This study’s goal was to provide dose-response data for a dopamine agonist in the baboon using standard methods (replicate measurements at each dose, across a range of doses), as a standard against which to subsequently validate a novel pharmacological MRI (phMRI) method. Dependent variables were functional MRI (fMRI) data from brain regions selected a priori, and systemic prolactin release. Necessary first steps included estimating the magnitude and time course of prolactin response to anesthesia alone and to various doses of agonist. These first steps (“time course studies”) were performed with three agonists, and the results were used to select …

Welcome To The Journal Of Evolution And Health, Aaron Blaisdell, Paul Jaminet, David C. Pendergrass

Aaron P Blaisdell

Welcome to the first issue of the Journal of Evolution and Health! The Journal of Evolution and Health is the peer-reviewed, open-access journal of the Ancestral Health Society, a community of scientists, healthcare professionals, and laypersons who collaborate to understand health challenges from an evolutionary perspective.

Seizure Protection By Intrapulmonary Delivery Of Midazolam In Mice, Ashish Dhir, Dorota Zolkowska, Michael A. Rogawski

Michael A. Rogawski

The lung provides a portal of entry that could be used to rapidly deliver anticonvulsant substances to the brain to treat seizures. In the present study, we demonstrate that midazolam, a water-soluble anticonvulsant benzodiazepine, confers potent seizure protection when administered via the intrapulmonary route. High dose (100 mg/kg) intraperitoneal midazolam induced loss-of-righting reflex in mice. Lower doses of midazolam (100–1000 μg/kg) when administered intraperitoneally did not induce loss-of-righting reflex but protected animals against pentylenetetrazol (PTZ)-induced seizures. Intrapulmonary administration of midazolam via a tracheal cannula protected against intraperitoneal PTZ seizures at lower doses. The minimal intraperitoneal and intravenous doses of midazolam …