Medical Toxicology Commons^™

Multifactorial Modulation Of The Blood-Brain Barrier: Relationship To Stroke, Bei Zhang

Theses and Dissertations--Nutritional Sciences

The blood-brain barrier (BBB) is a dynamic interface, mainly consisting of highly specialized brain microvascular endothelial cells (BMECs) that segregate the central nervous system (CNS) from the peripheral circulation. Impairment of the BBB, due to disruption of tight junction (TJ) proteins and inflammatory responses, may initiate and/or contribute to the progress of CNS disorders, including stroke. Stroke is the second leading cause of death worldwide. It has been shown that aging and environmental pollutants can induce brain endothelium dysfunction, and are considered as risk factors for stroke.

Deficiency of telomerase is highly linked with aging-associated vascular diseases. Evidence indicates that …

Effects Of Cellular Heterogeneity And Immune Cells In Angiotensin Ii-Infused Hemorrhaged Ascending Aortas, Kyung Sik Jung

Theses and Dissertations--Toxicology and Cancer Biology

A previous thoracic aortic aneurysm time course study from our laboratory determined that ascending aortic dilation was significantly increased by day 5, and reached a plateau by day 28 of angiotensin II (AngII) infusion. We also found that mice had hemorrhage localized to the ascending aortas by day 5 of AngII infusion. The purpose of these studies was to provide mechanistic insight into the development of AngII-induced ascending aortic hemorrhage.

Male C57BL/6 mice fed normal diet were subcutaneously infused with either AngII (1000 ng/kg/min) or saline for 5 days. To examine cellular heterogeneity, hemorrhaged ascending aortas were collected and sectioned …

Effects Of Endothelial Progenitor Cell-Derived Microvesicles On Hypoxia/Reoxygenation-Induced Endothelial Dysfunction And Apoptosis, Jinju Wang, Shuzhen Chen, Xioatang Ma, Chuanfang Cheng, Xiang Xiao, Ji Chen, Shiming Liu, Bin Zhao, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

Oxidative stress-induced endothelial dysfunction plays a key role in ischemia/reperfusion injury. Recent evidence indicates that endothelial progenitor cell-derived microvesicles (EPC-MVs) can promote angiogenesis of endothelial cells (ECs). Here, we investigated the potential effects of EPC-MVs on hypoxia/reoxygenation (H/R) injury in human brain microvascular ECs (hb-ECs). MVs were prepared from EPCs cultured in a serum deprivation (SD) medium (starving stress, sEPC-MVs) or SD medium containing tumor necrosis factor-α (TNFα) (apoptotic stress, aEPC-MVs). H/R injury model of hb-ECs was produced by 6 hr hypoxia (1% O₂) and 24 hr reoxygenation. The H/R hb-ECs were co-cultured with EPC-MVs. Results showed that …

Is Rimonabant A Safe And Effective Treatment For Patients With Alcohol Dependence?, Samantha L. Hughes

PCOM Physician Assistant Studies Student Scholarship

OBJECTIVE: The objective of this selective EBM review is to determine whether or not Rimonabant is a safe and effective treatment for patients with alcohol dependence.

STUDY DESIGN: Systematic review of three English language randomized control trials published in 2005, 2008 and 2010.

DATA SOURCES: Three double-blind, placebo controlled randomized trials comparing Rimonabant or Naltrexone to placebo were found using PubMed, OVID, Medline and Cochrane.

OUTCOMES MEASURED: Outcomes measured include event rate of heavy drinking days using the timeline follow back method, which facilitates self-reporting of drinking habits by utilizing calendars and personal recall. Other outcomes measured include …

Using The Theory Of Planned Behavior As A Predictor Of Radiologic Technologists' Use Of Patient Radiation Protection Best Practices: A Regional Study, Brenda L. Boyd

Dissertations

Problem. A growing concern exists that patients are receiving an increase in radiation exposure while undergoing medical imaging exams. According to a March 2009 report by the National Council on Radiation Protection and Measurements (NCRP), the U.S. population's total exposure to ionizing radiation has nearly doubled over the past two decades. With the introduction of new digital radiology equipment, patient dose is on the rise. Possible reasons for a radiologic technologist's behavior include: influence by availability or lack of equipment, policies, social pressure, attitudes, and a safety culture. Little research has been done in this area, specifically with applying a …

Luteolin Inhibits Human Prostate Tumor Growth By Suppressing Vascular Endothelial Growth Factor Receptor 2-Mediated Angiogenesis, Poyil Pratheeshkumar, Young-Ok Son, Amit Budhraja, Xin Wang, Songze Ding, Lei Wang, Andrew Hitron, Jeong-Chae Lee, Donghern Kim, Sasidharan Padmaja Divya, Gang Chen, Zhuo Zhang, Jia Luo, Xianglin Shi

Toxicology and Cancer Biology Faculty Publications

Angiogenesis, the formation of new blood vessels from pre-existing vascular beds, is essential for tumor growth, invasion, and metastasis. Luteolin is a common dietary flavonoid found in fruits and vegetables. We studied the antiangiogenic activity of luteolin using in vitro, ex vivo, and in vivo models. In vitro studies using rat aortic ring assay showed that luteolin at non-toxic concentrations significantly inhibited microvessel sprouting and proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Luteolin also inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM) …

Lack Of P53 Affects The Expression Of Several Brain Mitochondrial Proteins: Insights From Proteomics Into Important Pathways Regulated By P53, Ada Fiorini, Rukhsana Sultana, Eugenio Barone, Giovanna Cenini, Marzia Perluigi, Cesare Mancuso, Jian Cai, Jon B. Klein, Daret K. St. Clair, D. Allan Butterfield

Chemistry Faculty Publications

The tumor suppressor protein p53 has been described "as the guardian of the genome" for its crucial role in regulating the transcription of numerous genes responsible for cells cycle arrest, senescence, or apoptosis in response to various stress signals. Although p53 promotes longevity by decreasing the risk of cancer through activation of apoptosis or cellular senescence, several findings suggest that an increase of its activity may have deleterious effects leading to selected aspects of the aging phenotype and neurodegenerative diseases. There is the link between p53 and oxidative stress, the latter a crucial factor that contributes to neurodegenerative processes like …

Nadph Oxidase 4 Mediates Insulin-Stimulated Hif-1Α And Vegf Expression, And Angiogenesis In Vitro, Dan Meng, Aihong Mei, Junxu Liu, Xueling Kang, Xianglin Shi, Ruizhe Qian, Sifeng Chen

Toxicology and Cancer Biology Faculty Publications

Acute intensive insulin therapy causes a transient worsening of diabetic retinopathy in type 1 diabetes patients and is related to VEGF expression. Reactive oxygen species (ROS) have been shown to be involved in HIF-1α and VEGF expression induced by insulin, but the role of specific ROS sources has not been fully elucidated. In this study we examined the role of NADPH oxidase subunit 4 (Nox4) in insulin-stimulated HIF-1α and VEGF expression, and angiogenic responses in human microvascular endothelial cells (HMVECs). Here we demonstrate that knockdown of Nox4 by siRNA reduced insulin-stimulated ROS generation, the tyrosine phosphorylation of IR-β and IRS-1, …

Nevirapine Hepatotoxicity: Case Report And Discussion, Matt Baichi

The Medicine Forum

Nevirapine (viramune) is a nonnucleoside reverse transcriptase inhibitor commonly used in combination with other antiretroviral medicines in the treatment of HIV/AIDS. The safety profile of nevirapine, as determined by review of prospective clinical trials, reports rash with an incidence of 16% as the most common side effect. Clinical hepatitis is reported to occur with an incidence of 1%. A review of the literature shows many case reports of nevirapine-induced hepatotoxicity in patients receiving both treatment and prophylaxis for HIV. The purpose of this case report is to stress the importance of early recognition and withdrawal of the offending drug.

Quercetin Inhibits Angiogenesis Mediated Human Prostate Tumor Growth By Targeting Vegfr- 2 Regulated Akt/Mtor/P70s6k Signaling Pathways, Poyil Pratheeshkumar, Amit Budhraja, Young-Ok Son, Xin Wang, Zhuo Zhang, Songze Ding, Lei Wang, Andrew Hitron, Jeong-Chae Lee, Mei Xu, Gang Chen, Jia Luo, Xianglin Shi

Toxicology and Cancer Biology Faculty Publications

Angiogenesis is a crucial step in the growth and metastasis of cancers, since it enables the growing tumor to receive oxygen and nutrients. Cancer prevention using natural products has become an integral part of cancer control. We studied the antiangiogenic activity of quercetin using ex vivo, in vivo and in vitro models. Rat aortic ring assay showed that quercetin at non-toxic concentrations significantly inhibited microvessel sprouting and exhibited a significant inhibition in the proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Most importantly, quercetin treatment inhibited ex vivo angiogenesis …

Interprofessional Education In Didactic And Experiential Settings At The Jefferson School Of Pharmacy, Elena M. Umland, Cynthia A. Sanoski, Emily R. Hajjar, Bhavik Shah

College of Pharmacy Faculty Papers

Presented at: 2012 Annual Meeting of the American Association of Colleges of Pharmacy in Kissimmee, Florida.

Objective:

To evaluate the various IPE offerings at a new school of pharmacy at a large academic medical center.

Human Endometrial Stromal Stem Cells Differentiate Into Megakaryocytes With The Ability To Produce Functional Platelets, Jinju Wang, Shuzhen Chen, Cheng Zhang, Samantha Stegeman, Teresa Pfaff-Amesse, Ying Zhang, Wenfeng Zhang, Lawrence Amesse, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

Human endometrium is a high dynamic tissue that contains endometrial stromal stem cells (hESSCs). The hESSCs have been differentiated into a number of cell lineages. However, differentiation of hESSCs into megakaryocytes (MKs) has not yet been investigated. The aim of this study was to investigate the feasibility of MK generation from hESSCs and subsequent production of functional platelets (PLTs). In our study, hESSCs were cultured from endometrial stromal cells as confirmed by positive stromal cell specific markers (CD90 and CD29) and negative hematopoietic stem cell markers (CD45 and CD34) expression. Then, hESSCs were differentiated in a medium supplemented with thrombopoietin …

Weaponizing Tear Gas: Bahrain’S Unprecedented Use Of Toxic Chemical Agents Against Civilians., Richard Sollom, Holly G. Atkinson

Publications and Research

The Bahraini government’s response to the early 2011 pro-democracy protests was brutal, systematic, and violent. In addition to birdshot and rubber bullets, government law enforcement attacked unarmed protestors with toxic chemical agents including tear gas. The government’s crackdown on the medical profession was especially harmful, as security forces arrested and detained doctors, raided health facilities, and obstructed patients from receiving necessary care. This report’s findings are based on field research that the authors conducted in Bahrain (April 2012) to investigate excessive use of force by law enforcement officials since June 2011—the end of Bahrain’s state of emergency. The medico-legal team …

Associations Between Toenail Arsenic Concentration And Dietary Factors In A New Hampshire Ppopulation, Joann F. Gruber, Margaret R. Karagas, Diane Gilbert-Diamond, Pamela J. Bagley, M Scot Zens, Vicki Sayarath, Tracy Punshon, J Steven Morris, Kathryn L. Cottingham

Dartmouth Scholarship

Background: Dietary factors such as folate, vitamin B12, protein, and methionine are important for the excretion of arsenic via one-carbon metabolism in undernourished populations exposed to high levels of arsenic via drinking water. However, the effects of dietary factors on toenail arsenic concentrations in well-nourished populations exposed to relatively low levels of water arsenic are unknown.

Methods: As part of a population-based case-control study of skin and bladder cancer from the USA, we evaluated relationships between consumption of dietary factors and arsenic concentrations in toenail clippings. Consumption of each dietary factor was determined from a validated food frequency questionnaire. We …

Uptake And Toxic Effects Of Surface Modified Nanomaterials In Freshwater Aquatic Organisms, Brandon Seda

All Dissertations

Nanomaterials are a class of materials with unique properties due to their size, and the association of these properties with the toxicity of nanomaterials is poorly understood. The present study assessed the toxic effects of stable aqueous colloidal suspensions of three distinctly different classes of nanomaterials in aquatic organisms. The fullerene, C70, was stabilized through non-covalent surface modification with gallic acid. Toxicity of C70-gallic acid was confirmed to exhibit similar toxic effects as C60-fullerene, including changes in antioxidative processes in Daphnia magna. Daphnia magna fecundity was significantly reduced in 21d bioassays at C70-gallic concentrations below quantifiable limits (0.03 mg/L C70). …

Effects Of Restricted Fructose Access On Body Weight And Blood Pressure Circadian Rhythms, Danielle Senador, Swapnil Vijay Shewale, Maria Claudia Irigoyen, Khalid M. Elased, Mariana Morris

Pharmacology and Toxicology Faculty Publications

High-fructose diet is known to produce cardiovascular and metabolic pathologies. The objective was to determine whether the timing of high fructose (10% liquid solution) intake affect the metabolic and cardiovascular outcomes. Male C57BL mice with radiotelemetric probes were divided into four groups: (1) 24 h water (control); (2) 24 h fructose (F24); (3) 12 h fructose during the light phase (F12L); (4) 12 h fructose during the dark phase (F12D). All fructose groups had higher fluid intake. Body weight was increased in mice on restricted access with no difference in total caloric intake. Fasting glycemia was higher in groups with …

Inverse Relationship Between Psa And Il-8 In Prostate Cancer: An Insight Into A Nf-Κb-Mediated Mechanism, Yong Xu, Daret K. St. Clair, Fang Fang, William H. St. Clair

Toxicology and Cancer Biology Faculty Publications

Background: Prostate specific antigen (PSA) is traditionally used as an indicator for the presence of prostate cancer (PCa) and radiotherapy is generally used to treat inoperable and locally advanced PCa. However, how cellular PSA level is associated with sensitivity of PCa to radiotherapy is unknown. The previous finding that the RelB-based NF-κB alternative pathway differentially regulates PSA and interleukin-8 (IL-8) in aggressive PCa has directed our attention to the role of RelB in the response of PCa to radiotherapy.

Methodology/Principal Findings: RelB and its targets PSA and IL-8 in PCa cells were manipulated by ectopic expression in PCa …

Identifying And Reducing Potential Risks Of Contamination In Food Packaging, Jeffrey Daniel Stollenwerk

Graphic Communication

The purpose of this study was to identify the possible health hazards in food packaging and evaluate each component of food packaging for risks and potential improvements. There have been recent cases in which contaminants have been identified in various food packaging products that pose potential harm to consumers. National authorities, like the Food and Drug Administration and the European Food Standards Agency, regulate these contaminants and create regulations for industry standards.

Contaminants travel from food packaging to the food-surface through a process called migration. Migration varies depending on the usage of different substrates, inks, varnishes, and printing technologies. Each …

Ex Vivo And In Vivo Methods And Related Compositions For Generating Hematopoietic Stem Cell Populations, Gary Van Zant, Ying Liang

Toxicology and Cancer Biology Faculty Patents

Various embodiments provide methods and related compositions for increasing the population size of hematopoietic stem cells (HSCs) in patients that may benefit from reconstitution of stem cells and/or differentiated cells of the blood lineage. The present methods enable the production of HSCs ex vivo and in vivo by reducing latexin expression and/or latexin activity within HSC exposed to various antagonists. Inhibition of latexin expression and/or latexin activity by various antagonists can promote HSC proliferation and/or inhibit HSC apoptosis. Antagonists that can reduce latexin expression and/or latexin activity can be utilized to regenerate endogenous HSCs within patients affected with disorders, diseases, …

The Use Of Cerium Oxide And Curcumin Nanoparticles As Therapeutic Agents For The Treatment Of Ventricular Hypertrophy Following Pulmonary Arterial Hypertension, Madhukar Babu Kolli

Theses, Dissertations and Capstones

Pulmonary arterial hypertension (PAH) is a progressive and fatal disease characterized by inflammation, increased pulmonary vascular resistance, right ventricular failure and premature death. Monocrotaline (MCT) has been used to induce PAH in laboratory rats. Previous in vitro and in vivo work suggested that cerium oxide (CeO2)-and curcumin nanoparticles exhibit anti-inflammatory activity; however, it is unknown if these materials are effective for the treatment of PAH induced cardiac hypertrophy. To determine the efficacy of CeO2 nanoparticle treatment in preventing MCT-induced RV hypertrophy, male Sprague Dawley rats were divided into one of three groups (control, MCT, or MCT + CeO2 nanoparticle, n=6/group). …