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Estrogen Sulfotransferase (Sult1e1) Expression And Function In Mcf10a-Series Breast Epithelial Cells: Role As A Modifier Of Breast Carcinogenesis And Regulation By Proliferation State, Jiaqi Fu 2011 Wayne State University

Estrogen Sulfotransferase (Sult1e1) Expression And Function In Mcf10a-Series Breast Epithelial Cells: Role As A Modifier Of Breast Carcinogenesis And Regulation By Proliferation State, Jiaqi Fu

Wayne State University Dissertations

Estrogen sulfotransferase (SULT1E1) catalyzes the sulfonation of estrogens, which limits estrogen mitogenicity. TaqMan Gene Expression assays were used to profile the mRNA expression of estrogen receptor (ERα and ERβ) and estrogen metabolism enzymes including cytosolic sulfotransferases (SULT1E1, SULT1A1, SULT2A1, and SULT2B1), steroid sulfatase (STS), aromatase (CYP19), 17β-hydroxysteroid dehydrogenases (17βHSD1 and 2), CYP1B1, and catechol-O-methyltransferase (COMT) in an MCF10A-derived lineage cell culture model for basal-like human breast cancer progression and in ERα-positive luminal MCF7 breast cancer cells. Low levels of ERα and ERβ mRNA were present in MCF10A-derived cell lines. SULT1E1 mRNA was more abundant in confluent relative to subconfluent MCF10A ...


Compensatory Renal Hypertrophy, Mitochondria And Redox Status, Bavneet Benipal 2011 Wayne State University

Compensatory Renal Hypertrophy, Mitochondria And Redox Status, Bavneet Benipal

Wayne State University Dissertations

A reduction in functional renal mass occurs in humans during aging and severe kidney damage from diseases, injuries, infections and congenital conditions and after nephrectomy. Nephrectomy, or surgical removal of a kidney or a section of a kidney, is performed for treatment of unilateral secondary renal cancer, infections and for kidney transplantation. As a result, the remaining renal tissue undergoes compensatory growth due primarily to hypertrophy, in which both the size and functional capacity of the remaining kidney are increased. Renal compensatory hypertrophy is associated with a series of physiological, morphological and biochemical changes that also have toxicological implications.

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The Effects Of Methylmercury On Corticosterone And Thyroid Hormones In A Breeding Songbird Model Organism, Sarah Ross Lemelin 2011 College of William & Mary - Arts & Sciences

The Effects Of Methylmercury On Corticosterone And Thyroid Hormones In A Breeding Songbird Model Organism, Sarah Ross Lemelin

Dissertations, Theses, and Masters Projects

No abstract provided.


Compensatory Mechanisms Of Neuroprotection By Pkd Signaling Against Oxidative Damage In Experimental Models Of Parkinson's Disease (Pd): Relevance To Pd Drug Discovery Strategies, Arunkumar Asaithambi 2011 Iowa State University

Compensatory Mechanisms Of Neuroprotection By Pkd Signaling Against Oxidative Damage In Experimental Models Of Parkinson's Disease (Pd): Relevance To Pd Drug Discovery Strategies, Arunkumar Asaithambi

Graduate Theses and Dissertations

Oxidative stress is a key pathophysiological mechanism contributing to the selective degeneration of dopaminergic neurons in Parkinson's disease. Unraveling the molecular mechanisms underlying various stages of oxidative neuronal damage is critical to better understanding the diseases and developing new treatment modalities. In this study, we identified that protein kinase D1 (PKD1) functions as a key anti-apoptotic kinase to protect neuronal cells against early stages of oxidative stress. Blockade of PKCδ cleavage, PKCδ knockdown or overexpression of a cleavage-resistant PKCδ mutant effectively attenuated PKD1 activation, indicating that PKCδ proteolytic activation regulates PKD1 phosphorylation. We also identified that phosphorylation of S916 ...


Effects Of Chemically Characterized Fractions From Aerial Parts Of Echinacea Purpurea And E. Angustifolia On Myelopoiesis In Rats, Sindhura Ramasahayam, Hany N. Baraka, Fatma M. Abdel Bar, Bilal S. Abusal, Mark P. Widrlechner, Khalid A. El Sayed, Sharon A. Meyer 2011 University of Louisiana at Monroe

Effects Of Chemically Characterized Fractions From Aerial Parts Of Echinacea Purpurea And E. Angustifolia On Myelopoiesis In Rats, Sindhura Ramasahayam, Hany N. Baraka, Fatma M. Abdel Bar, Bilal S. Abusal, Mark P. Widrlechner, Khalid A. El Sayed, Sharon A. Meyer

NCRPIS Publications and Papers

Echinacea species are used for beneficial effects on immune function, and various prevalent phytochemicals have immunomodulatory effects. Using a commercial E. purpurea (L.) Moench product, we have evaluated the myelopoietic effect on bone marrow of rats treated with various extracts and correlated this with their chemical class composition. Granulocyte/macrophage-colony forming cells (GM-CFCs) from femurs of female Sprague-Dawley rats were assessed at 24 h after 7 daily oral treatments. A 75 % ethanolic extract at 50 mg dried weight (derived from 227 mg aerial parts) per kg body weight increased GM-CFCs by 70 % but at 100 mg/kg was without effect ...


Field-Evolved Resistance To Bt Maize By Western Corn Rootworm, Aaron J. Gassmann, Jennifer L. Petzold-Maxwell, Ryan Scott Keweshan, Michael Wilson Dunbar 2011 Iowa State University

Field-Evolved Resistance To Bt Maize By Western Corn Rootworm, Aaron J. Gassmann, Jennifer L. Petzold-Maxwell, Ryan Scott Keweshan, Michael Wilson Dunbar

Entomology Publications

Crops engineered to produce insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt) are planted on millions of hectares annually, reducing the use of conventional insecticides and suppressing pests. However, the evolution of resistance could cut short these benefits. A primary pest targeted by Bt maize in the United States is the western corn rootwormDiabrotica virgifera virgifera (Coleoptera: Chrysomelidae). We report that fields identified by farmers as having severe rootworm feeding injury to Bt maize contained populations of western corn rootworm that displayed significantly higher survival on Cry3Bb1 maize in laboratory bioassays than did western corn rootworm from fields ...


Development Of A Tier-1 Assay For Assessing The Toxicity Of Insecticidal Substances Against Coleomegilla Maculata, Yunhe Li, Jared Ostrem, Jörg Romeis, Mao Chen, Xiaoxia Liu, Richard L. Hellmich, Anthony M. Shelton, Yufa Peng 2011 Cornell University

Development Of A Tier-1 Assay For Assessing The Toxicity Of Insecticidal Substances Against Coleomegilla Maculata, Yunhe Li, Jared Ostrem, Jörg Romeis, Mao Chen, Xiaoxia Liu, Richard L. Hellmich, Anthony M. Shelton, Yufa Peng

Entomology Publications

To assess the potential dietary effects of insecticidal substances on the predacious ladybird beetle, Coleomegilla maculata De Geer, a Tier-1 laboratory testing system was developed. Artificial diets using shrimp eggs were developed, and a tier-1 bioassay examining C. maculata development and survival was designed based on those diets. To further measure the artificial diet in a Tier-1 testing system, larvae of C. maculata were fed the diet treated with different concentrations of an inorganic stomach poison, potassium arsenate (PA), or a cysteine protease inhibitor, E-64. The results demonstrated that the testing system was capable of detecting the dietary effects of ...


Effects Of Dietary Mercury Exposure On Spatial Memory Of Zebra Finches, Taeniopygia Guttata, Amanda Mae Bessler 2011 College of William & Mary - Arts & Sciences

Effects Of Dietary Mercury Exposure On Spatial Memory Of Zebra Finches, Taeniopygia Guttata, Amanda Mae Bessler

Dissertations, Theses, and Masters Projects

No abstract provided.


Identification Of Activities Involved In Cag/Ctg Repeat Instability, Nelson Lap Shun Chan 2011 University of Kentucky

Identification Of Activities Involved In Cag/Ctg Repeat Instability, Nelson Lap Shun Chan

University of Kentucky Doctoral Dissertations

CAG/CTG repeat instability is associated with at least 14 neurological disorders, including Huntington’s disease and Myotonic dystrophy type 1. In vitro and in vivo studies have showed that CAG/CTG repeats form a stable hairpin that is believed to be the intermediate for repeat expansion and contraction.

Addition of extra DNA is essential for repeat expansion, so DNA synthesis is one of the keys for repeat expansion. In vivo studies reveal that 3’ CTG slippage with subsequent hairpin formation (henceforth called the 3’ CTG slippage hairpin) occurs during DNA synthesis. It is proposed that hairpin tolerance machinery is ...


Genotoxin-Induced Acetylation Of The Werner Syndrome Protein (Wrn) And Effect On Its Dna Metabolic Function, Enerlyn Meliza Lozada Santiago 2011 University of Kentucky

Genotoxin-Induced Acetylation Of The Werner Syndrome Protein (Wrn) And Effect On Its Dna Metabolic Function, Enerlyn Meliza Lozada Santiago

University of Kentucky Doctoral Dissertations

Loss of function of the WRN protein causes the genetic disorder Werner Syndrome that is characterized by increased cancer and premature aging. WRN belongs to the RecQ helicase family that plays key roles in preventing genome instability. In response to treatment with genotoxins, WRN is subject to post-translational modification. The relationship of post-translational modification of WRN with its function in DNA metabolism is unknown. There is accumulating evidence suggesting that WRN contributes to the maintenance of genomic integrity through its involvement in DNA replication. Consistent with this notion, WS cells are sensitive to DNA replication inhibitors and DNA damaging agents ...


Sublethal Toxicity Of Microcystis And Microcystin-Lr In Fish, Emily Dawn Rogers 2010 University of Tennessee - Knoxville

Sublethal Toxicity Of Microcystis And Microcystin-Lr In Fish, Emily Dawn Rogers

Doctoral Dissertations

The occurrence of blooms of toxic cyanobacteria in freshwater environments is a global ecological and public health concern. Species of Microcystis are of particular importance because blooms occur in many freshwater environments throughout the world and microcystin toxin concentrations can exceed World Health Organization advisory levels. While microcystin has been associated with fish kills, sublethal effects of chronic exposure at environmentally relevant concentrations are relatively unknown. The objective of this research was to evaluate toxicity of microcystin and Microcystis in fish during all life history stages. We evaluated global gene expression response in larval zebrafish (Danio rerio), and a sub-set ...


Mycotoxins In Grains – Causes, Prevention And Control, Hester F. Vismer 2010 Medical Research Council (Cape Town, South Africa)

Mycotoxins In Grains – Causes, Prevention And Control, Hester F. Vismer

INTSORMIL Presentations

Discusses mycotoxins, their effect on grain, mitigation considerations, and resulting human toxicology.


Pharmacokinetic Evaluation Of The Blood: Tissue Relationship In Poultry: Screening For Antibiotic Residues In Chicken Muscle, Ixchel Reyes Herrera 2010 University of Arkansas, Fayetteville

Pharmacokinetic Evaluation Of The Blood: Tissue Relationship In Poultry: Screening For Antibiotic Residues In Chicken Muscle, Ixchel Reyes Herrera

Theses and Dissertations

During their life, humans are exposed to numerous substances that are naturally present in the environment or that are the result of man made processes, including heavy metals, persistent organic pollutants, pesticides and veterinary drugs. Some of these substances can leave residues in food products and possibly expose consumers to their potential toxic effects. To address these problems extensive regulatory efforts are devoted to prevent, detect and control these substances from reaching the food supply. However, given the vast diversity of food products that requires monitoring and the immense diversity of potential chemical contaminants, the need for an efficient and ...


Accident In Bhopal: Observations 20 Years Later, Ronald J. Willey, Dennis C. Hendershot, Scott Berger 2010 Northeastern University

Accident In Bhopal: Observations 20 Years Later, Ronald J. Willey, Dennis C. Hendershot, Scott Berger

Ronald J. Willey

The most influential process safety accident passed its 20th anniversary on Dec 3, 2004. At an international symposium to mark the event in Kanpur, India during the week of this anniversary, process safety practitioners from around the world assembled to discuss progress in resolving the Bhopal tragedy and in advancing the practice of process safety worldwide. This paper reports the main conclusions from the conference, and provides insight into the Bhopal site as attendees found it in December 2004. Since 1984, many positive steps worldwide have been made in regards to improvements in process safety and protection of personnel within ...


Aluminium Phosphide Poisoning: A Case Report, Shela Akbar Ali Hirani, Arshalooz Rahman 2010 Aga Khan University

Aluminium Phosphide Poisoning: A Case Report, Shela Akbar Ali Hirani, Arshalooz Rahman

School of Nursing & Midwifery

This paper reports the case of a family in which three children were presented at Emergency Room (ER) with poisoning after the use of a pesticide at home. Initially, the cases were managed as routine cases of organophosphorus poisoning; however, the death of two children made the health team members realise that the poison's effects were delayed and devastating. Later, the compound was identified as Aluminium Phosphide (ALP), and the life of the last surviving child in the family was saved.


Analysis Of Anthropogenic Effects On Topsoil Throughout The California Polytechnic State University Campus In San Luis Obispo, Brooke L. Hamilton 2010 California Polytechnic State University - San Luis Obispo

Analysis Of Anthropogenic Effects On Topsoil Throughout The California Polytechnic State University Campus In San Luis Obispo, Brooke L. Hamilton

Earth and Soil Sciences

Soils reflect the health of a landscape, and in many cases carry the burden of anthropogenic activity, continually changing in characteristics such as pH, soil texture, soil structure, carbon:nitrogen ratios (C:N), and chemical composition. In a study sampling six different soils on the California Polytechnic State University campus in San Luis Obispo, these five soil characteristics were tested for and the results were determined. Soil samples consist of the top 5-10 cm of soil profiles, with sample sites varying according to degree of human contact; the locations the samples were taken from are as follows: (1) Walters Creek ...


Meeting The Common Needs Of A More Effective And Efficient Testing And Assessment Paradigm For Chemical Risk Management, Steven P. Bradbury, Vicki Dellarco, Tala Henry, Phil Sayre, Jennifer Seed 2010 Iowa State University

Meeting The Common Needs Of A More Effective And Efficient Testing And Assessment Paradigm For Chemical Risk Management, Steven P. Bradbury, Vicki Dellarco, Tala Henry, Phil Sayre, Jennifer Seed

Steven P. Bradbury

Significant advances have been made in human health and ecological risk assessment over the last decade. Substantial challenges, however, remain in providing credible scientific information in a timely and efficient manner to support chemical risk assessment and management decisions. A major challenge confronting risk managers is the need for critical information to address risk uncertainties in large chemical inventories such as high- and medium-production-volume industrial chemicals or pesticide inert ingredients. From a strategic and tactical viewpoint, an integrated approach that relies on all existing knowledge and uses a range of methods, including those from emerging and novel technologies, is needed ...


Application Of The Tissue Residue Approach In Ecological Risk Assessment, Steven P. Bradbury, Keith G. Sappington, Todd S. Bridges, Russell J. Erickson, A. Jan Hendriks, Roman P. Lanno, James P. Meador, David R. Mount, Mike H. Salazar, Doug J. Spry 2010 Radboud University

Application Of The Tissue Residue Approach In Ecological Risk Assessment, Steven P. Bradbury, Keith G. Sappington, Todd S. Bridges, Russell J. Erickson, A. Jan Hendriks, Roman P. Lanno, James P. Meador, David R. Mount, Mike H. Salazar, Doug J. Spry

Steven P. Bradbury

The objective of this work is to present a critical review of the application of the tissue residue approach (TRA) in ecological risk and/or impact assessment (ERA) of chemical stressors and environmental criteria development. A secondary goal is to develop a framework for integrating the TRA into ecological assessments along with traditional, exposure concentration-based assessment approaches. Although widely recognized for its toxicological appeal, the utility of the TRA in specific applications will depend on numerous factors, such as chemical properties, exposure characteristics, assessment type, availability of tissue residue-response data, and ability to quantify chemical exposure. Therefore, the decision to ...


Characterization Of Arsd: An Arsenic Chaperone For The Arsab As(Iii)-Translocating Atpase, Jianbo Yang 2010 Wayne State University

Characterization Of Arsd: An Arsenic Chaperone For The Arsab As(Iii)-Translocating Atpase, Jianbo Yang

Wayne State University Dissertations

Arsenic is a metalloid toxicant that is widely distributed throughout the earth's crust and causes a variety of health and environment problems. As an adaptation to arsenic-contaminated environments, organisms have developed resistance systems. In bacteria and archaea various ars operons encode ArsAB ATPases that pump the trivalent metalloids As(III) or Sb(III) out of cells. In these operons, an arsD gene is almost always adjacent to the arsA gene, suggesting a related function. ArsA is the catalytic subunit of the pump that hydrolyzes ATP in the presence of arsenite or antimonite. ArsB is a membrane protein which containing ...


Expression Of The Periplaneta Americana's Α-Adrenergic-Like Octopamine Receptor In The Yeast Saccharomyces Cerevisiae: A High-Throughput Screening System In Search Of Biorational Insecticides, Aaron Donald Gross 2010 Iowa State University

Expression Of The Periplaneta Americana's Α-Adrenergic-Like Octopamine Receptor In The Yeast Saccharomyces Cerevisiae: A High-Throughput Screening System In Search Of Biorational Insecticides, Aaron Donald Gross

Graduate Theses and Dissertations

The use of conventional synthetic insecticides is facing increased scrutiny due to environmental and mammalian health concerns along with resistance to target insects. This has led to an investigation of alternative control measures to combat both economically and medically important arthropods. Octopamine, a biogenic amine, has significant physiological functions in invertebrates, including insects, and signals through G-protein-coupled receptors (GPCRs). Co-evolution of plants with insects has led to plants adapting defensive mechanisms to deter herbivore, microbial, or viral attack. This is sometimes accomplished via the production of essential oils that are composed of a variety of compounds, in particular monoterpenoids, sesquiterpenoids ...


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