Toxicology Commons^™

Lead Activation Of A Developmentally Regulated Calcium Channel In Rat Hippocampal Nerve Terminals, Troy E. Rhodes

Theses and Dissertations in Biomedical Sciences

Low level lead (Pb²⁺) exposure may produce lasting deficits in learning and memory by altering calcium (Ca²⁺) dependent processes. Isolated presynaptic nerve terminals from rat hippocampus were loaded with the intracellular (Ca²⁺) indicator Fura-2. The changes in cytoplasmic free calcium ([Ca²⁺]_i) were measured by stopped-flow fluorescence spectroscopy following depolarization with elevated potassium on a millisecond time scale (Lentzner et al., 1992). Depolarization promoted a rapid increase in Ca²⁺_i which occured in two kinetically distinguishable phases: a fast component, representing the activity of rapidly inactivating Ca²⁺ channels (τ …

Fish Tissue Contamination In Maine Lakes : Data Report, Jeanne Difranco, Linda Bacon, Barry Mower, David Courtemanch

Maine Collection

Fish Tissue Contamination in Maine Lakes : Data Report

by Jeanne DiFranco, Linda Bacon, Barry Mower and David Courtemanch

Regional Environmental Monitoring and Assessment Program (REMAP)

State of Maine Department of Environmental Protection, Bureau of Land and Water Quality, Division of Environmental Assessment, State House Station 17, Augusta, Maine 04333 (September 1995).

Contents: List of Figures and Tables / I. Introduction / II. Goals and Objectives / III. Experimental Design / IV. Methods / V. Data / VI. Quality Assurance-Quality Control / Appendices A-H

Indomethacin Reduces Splenic Red Pulp Macrophage Populations In Female New Zealand White Rabbits, Thane S. Thurmond

Electronic Theses and Dissertations

In an effort to elucidate the mechanism by which indomethacin (IN) attenuates the stimulatory effect of estradiol (E$\sb2$) on rabbit splenic red pulp macrophages (RPM), thirty-nine female New Zealand White rabbits were divided into 10 groups: ovariectomized (OVX), OVX/IN at 0.1 and 5.0 mg/kg body weight (bw)/day; sham OVX (SOVX), SOVX/IN at 0.1 and 5.0 mg/kg bw/day; OVX/25 mg E2, OVX/25 mg E$\sb2$/IN at 0.1 and 5.0 mg/kg bw/day; intact Control. Quantitative changes in RPM population in response to the treatments were measured using a 0 to 4 histologic grading scale. Estradiol treatment resulted in increased RPM grade when compared …

State Of Maine Handbook For Hazardous Waste Generators, Department Of Environmental Protection

Maine Collection

State of Maine Handbook for Hazardous Waste Generators

Department of Environmental Protection, Augusta, Maine 1995.

Contents: Introduction to Hazardous Waste / Purpose of This Handbook / Who Generates Hazardous Waste and How? / How Do I Determine If I Generate Hazardous Waste? / Am I a Small Quantity Generator (SQG), an SQG Plus, or a Generator? / Hazardous Waste Management Practices / Manifesting Hazardous Waste / In Summary / Appendix A - D

Validation Of A Bag Sampling Method For 1,3-Butadiene, Lori Eckenrode

Community & Environmental Health Theses & Dissertations

At this time there is no NIOSH approved means for bag sampling 1,3-butadiene. An attempt was made to use the application of cold (0°F) to inhibit the reactivity of the gas prior to analysis. The State of California Air Resources Board has an approved method for the gas chromatographic analysis of 1,3-butadiene from stationary sources. The method was utilized in the application of industrial hygiene monitoring of affected workers. The application of cold was found to be ineffective at inhibiting the highly reactive nature of 1,3-butadiene. Analyte losses were too great to classify the method as an accurate measure of …

Effect Of Alcohol On The Postnatal Development Of Cerebellar Cortex In Rat Guste 1-Histological And Morphometric Studies., Mansoor Saleh, M N. Saleh, M A. Desouky, Saadia Sayed, Entesar Saber

Haematology and Oncology, East Africa

The effect of ethyl alcohol (10%) on the postnatal development of cerebellar cortex was studied using histological and morphometric methods. The external granular layer was much increased in thickness in alcohol fed rat than those of the control while the molecular and granular layer were reduced. The cells of themolecular layer showed neuronal degeneration and many spaces were present in this layer esp < /strong>ecially late postnatal. The Purkinje cells failed to reach their final position up the tenth day and still arranged in more than one row. The degenerative changes appeared at five days and increased with age. The extent …

The Effect Of Trimethyltin On The Cholinergic System Of The Rat Hippocampus, Richard L. Cannon

Electronic Theses and Dissertations

Trimethyltin (TMT) is a neurotoxin occurring in the environment. Exposure to (TMT) is known to destroy specific neuronal components of the hippocampus in the rat and to cause clinical symptoms in exposed humans, including mnemonic deficits, that indicate hippocampal involvement. In addition to hippocampal cell loss TMT causes significant increases in cholinergic markers such as acetylcholinesterase (AChE) stain density and choline acetyltransferase (ChAT) activity in the hippocampus of rats. However, despite these observations the effect of TMT on hippocampal cholinergic system has not been investigated in detail. The purpose of the present study was to elucidate more fully the consequences …

The Accumulation And Run-Down Of Dieldrin In Wethers Grazed On Paddocks Previously Treated With Dieldrin, Tony Albertsen, Roy Casey, Keith Croker

Journal of the Department of Agriculture, Western Australia, Series 4

In mid 1987, the organochlorines (O/Cs) DDT, dieldrin, heptachlor and chlordane were deregistered for agricultural and horticultural use in Australia. These chemicals had been used widely, and land on several hundred Western Australian farms, particularly where potatoes had been grown, was contaminated with chemical residues. Livestock grazing pastures on such land was also contaminated, and our beef exports were threatened. In 1988, the Western Australian Department of Agriculture started a two-year project to collect information from sheep which were grazed on land that had previously been treated with O/Cs, particularly dieldrin. The levels of O/Cs in body and wool fats …

Agenda For Action - Casco Bay, Department Of Environmental Protection

Maine Collection

Agenda For Action - Casco Bay

Department of Environmental Protection, Augusta, Maine (January, 1989)

Contents: Introduction / The Problems : Bacteria, Toxics, Nutrients / The Solutions / Recommendations / References

Maine Nonpoint Source Pollution Assessment Report, Bureau Of Water Quality Control

Maine Collection

Maine Nonpoint Source Pollution Assessment Report

Prepared by the Maine Department of Environmental Protection, Bureau of Water Quality Control, Augusta, Maine 1989.

Contents: Executive Summary / Introduction / Methodology / Statewide Water Quality Summary / State And Local Agency Programs for Control of Nonpoint Source Pollution / Process for Identification of Best Management Practices and Associated Standards / List of References / List of Figures / List of Tables

Policy For Identifying And Assessing The Health Risks Of Toxic Substances, Maine Bureau Of Health

Maine Collection

Policy for Identifying and Assessing the Health Risks of Toxic Substances

by Norman T. Anderson, Environmental Toxicology Program, Division of Disease Control, Bureau of Health (February, 1988).

Contents: Section I: Introduction / Section II: Methods / Section III: Exposure Assessment / Section IV: Hazard Identification / Section V: Hazard Assessment / Section VI: Risk Characterization / List of Figures / List of Tables

Reactions Of Organic N-Chloramines In The Gastric Fluid Of The Rat, Kathryn E. Mazina

Chemistry & Biochemistry Theses & Dissertations

Using chlorine as a drinking water disinfectant may have potential health effects due to its reactivity with organic amino nitrogen compounds found in the stomach. Organic N-chloramines have been shown to form in the stomachs of laboratory rats. The possible reactions of N-chloramines in the stomach fluid were examined in this study using a model radiolabeled N-chloramine. ³⁶Cl-N-Chloropiperidine, was synthesized and purified to remove ³⁶Cl-chloride. Stomach fluid was obtained from Sprague-Dawley rats which had been first fasted for 24 or 48 hours and then administered 3 mL of deionized water. Different concentrations of radiolabeled chloramine were reacted with …

The Effects Of Tri-O-Cresyl Phosphate On 2',3'-Cyclicnucleotide-3'-Phosphohydrolase Activity In Neural And Non-Neural Tissue Of The Rat, Mark K. Schlager

Chemistry & Biochemistry Theses & Dissertations

A total of 44 Long-Evans rats received 5.7 g/kg tri-O-cresyl phosphate (TOCP) orally every 3 days for 6 days. A second group of 13 rats received 4.6 g/kg orally every 3 days for 6 days. Animals were administered atropine sulfate (10 mg/kg) intraperitoneally every 6 hours or as needed to alleviate cholinergic symptoms. Ten control animals were given corn oil orally. Eight rats (18%) survived the 5.7 g/kg dose regimen and 5 rats (38%) survived the 4.6 g/kg dose regimen. Surviving rats were killed at 30-33 days post-dose. Signs of delayed neuropathy included ataxia and motor impairment.

The CNP activity …

Effects Of Organic Compounds On Amphibian Reproduction, Wesley J. Birge, Jeffrey A. Black, Robert A. Kuehne

KWRRI Research Reports

Aquatic toxicity tests were conducted with atrazine, carbon tetrachloride, chloroform, methylene chloride, trisodium nitrilotriacetic acid (NTA), and phenol. Each compound was administered to developmental stages of three to five amphibian species. Exposure was initiated at fertilization and maintained through 4 days posthatching. Test responses included lethality and teratogenesis. Different amphibian species exhibited varying degrees of tolerance to the selected compounds. Greatest tolerance usually was observed for the more broadly adapted semi-aquatic and terrestrial species (e.g., Bufo americanus, Bufo fowleri). The more sensitive amphibians usually included those species which normally are restricted to aquatic or moist habitats (e.g., Rana …

Bulletin 3967 - Cyanogenetic Plants Of Western Australia, T E H Aplin

Bulletins - 3000 - 3999

This article deals with those native, naturalized and cultivated plants, which by virtue of contained cyanogenetic glycosides, are known to be poisonous or potentially poisonous to livestock in Western Australia.

Cyanogenetic glycosides are chemical compounds which contain a cyanogen (cyanide) radical combined with a sugar molecule. The sugar moiety may differ in glycosides obtained from different plants, and as a consequence glycosides from different plants, containing different sugar moieties, may be given different names.

When a cyanogenetic glycoside is broken down by enzyme action, through injury to the plant or by microbial action in the digestive system of the animal, …

Pesticide Residues In The Illinois Wild Turkey, John M. Bridges

Masters Theses

Adipose tissue from 55 turkeys, killed during the 1974 hunting season in southern Illinois, was grouped by age and location of the birds, and the pesticide concentrations in them were determined by gas/liquid chromatography. Twelve different pesticides were identified in the samples with only four, total DDT, heptachlor epoxide, toxaphene, and linuron, being present in all samples. Concentrations ranged from 0.02 ppm to 0.88 ppm.

The Great Potato Debate, James D. Hudson

Honors Theses

Anencephaly and spina bifida cystica are two of the most common severe congenital malformations consistently observed in human populations. Both represent defects in the neural tube and share a significant number of similar epidemiological associations among them, occupational class, geography, sex ratio, maternal age, year and season of the year. In anencephaly most of the brain and upper skull never form usually resulting in death within a few hours of birth. Spina bifida cystica is a malformation of the spinal cord often causing paralysis, vulnerability to infection, and early death. In 1972, Dr. J.H. Renwick presented a controversial hypothesis which …

A Comparative In Vitro Metabolic Study Of Certain Pesticidal Phenyl N-Methyl-Carbamates, Larry A. Wheeler

Loma Linda University Electronic Theses, Dissertations & Projects

Two critical parameters in the evaluation of the toxicological hazards of the use of carbamate pesticides are: (1) a rapid, sensitive, and precise analytical method of identification of the carbamate and its metabolites; and (2) their metabolism. A method in this study was developed whereby various carbamates and their metabolites could be chromatographed in the gaseous phase. Also, a comparative in vitro study of 15,000 g liver supernatants from human, rat, and dog was performed. Additional tissues investigated for metabolic activity toward the carbamates, Zectran and Mesurol, were kidney (from the dog only) and various blood fractions (red blood cells, …

Bulletin No 69 - The Poison Plants Of Western Australia, D. A. Herbert

Bulletins 1 - 2999

Up to the present no publication dealing with the whole of the known i)01S0fl plaits of Western Australia has been written. This Bulletin contains the collected accounts of various authors and correspondents which have been published at different times and contains a large amount of original information gathered both from field experience and from laboratory experiments. The work is not complete. A number of plants from distant districts have not been obtainable or obtainable only in amounts insufficient for exhaustive tests. These plants are comparatively few, however, and in Section 13 of this publication those which are suspected, but against …