Medical Toxicology Commons^™

Parasitic Contamination Of Soil In The Southern United States, Christine Crudo Blackburn, Sally Mingshuang Yan, David Mccormick, Lauren Nicholas Herrera, Roumen Borilov Iordanov, Mark Daniel Bailey, Maria Elena Bottazzi, Peter J Hotez, Rojelio Mejia

Faculty, Staff and Students Publications

Parasites are generally associated with lower income countries in tropical and subtropical areas. Still, they are also prevalent in low-income communities in the southern United States. Studies characterizing the epidemiology of parasites in the United States are limited, resulting in little comprehensive understanding of the problem. This study investigated the environmental contamination of parasites in the southern United States by determining each parasite's contamination rate and burden in five low-income communities. A total of 499 soil samples of approximately 50 g were collected from public parks and private residences in Alabama, Louisiana, Mississippi, South Carolina, and Texas. A technique using …

Communities Disproportionately Affected By Carbon Monoxide Exposure After Winter Storm Uri, Elyse N Portillo, Casandra Quiñones, Zachary C Foughty, Ryan Ramphul, Asha T Morrow, Kathryn Fisher, Stephen A Harding, Elizabeth A Camp, Shubhada Hooli, Eric A Russell

Faculty, Staff and Students Publications

Extreme cold in February 2021 precipitated prolonged power failure in Texas. In Houston, many patients presented for carbon monoxide exposure from neighborhoods with lower per capita income, higher rates of limited English proficiency, and greater median Social Vulnerability Indices than Greater Houston. Weather-related disasters disproportionately affect socially vulnerable communities.

Structures Of The Insecticidal Toxin Complex Subunit Xpta2 Highlight Roles For Flexible Domains, Cole L Martin, David W Chester, Christopher D Radka, Lurong Pan, Zhengrong Yang, Rachel C Hart, Elad M Binshtein, Zhao Wang, Lisa Nagy, Lawrence J Delucas, Stephen G Aller

Faculty, Staff and Students Publications

The Toxin Complex (Tc) superfamily consists of toxin translocases that contribute to the targeting, delivery, and cytotoxicity of certain pathogenic Gram-negative bacteria. Membrane receptor targeting is driven by the A-subunit (TcA), which comprises IgG-like receptor binding domains (RBDs) at the surface. To better understand XptA2, an insect specific TcA secreted by the symbiont

Clustering Of Pediatric Brain Tumors In Texas, 2000-2017, Thanh T Hoang, Omar Rosales, Elyse Burgess, Philip J Lupo, Michael E Scheurer, Abiodun O Oluyomi

Faculty, Staff and Students Publications

Risk factors for pediatric brain tumors are largely unknown. Identifying spatial clusters of these rare tumors on the basis of residential address may provide insights into childhood socio-environmental factors that increase susceptibility. From 2000-2017, the Texas Cancer Registry recorded 4305 primary brain tumors diagnosed among children (≤19 years old). We performed a spatial analysis in SaTScan to identify neighborhoods (census tracts) where the observed number of pediatric brain tumors was higher than expected. Within each census tract, the number of pediatric brain tumors was summed on the basis of residential address at diagnosis. The population estimate from the 2007-2011 American …

Botulinum Neurotoxin Injections In Children With Self-Injurious Behaviors, Mariam Hull, Mered Parnes, Joseph Jankovic

Faculty, Staff and Students Publications

Self-injurious behaviors are repetitive, persistent actions directed toward one's body that threaten or cause physical harm. These behaviors are seen within a broad spectrum of neurodevelopmental and neuropsychiatric conditions, often associated with intellectual disability. Injuries can be severe and distressing to patients and caregivers. Furthermore, injuries can be life-threatening. Often, these behaviors are challenging to treat and require a tiered, multimodal approach which may include mechanical/physical restraints, behavioral therapy, pharmacotherapy, or in some cases, surgical management, such as tooth extraction or deep brain stimulation. Here, we describe a series of 17 children who presented to our institution with self-injurious behaviors …

Spatial Analysis Of Drug Absorption, Distribution, Metabolism, And Toxicology Using Mass Spectrometry Imaging, Michelle L Spruill, Mirjana Maletic-Savatic, Howard Martin, Feng Li, Xinli Liu

Faculty, Staff and Students Publications

Mass spectrometry imaging (MSI) is emerging as a powerful analytical tool for detection, quantification, and simultaneous spatial molecular imaging of endogenous and exogenous molecules via in situ mass spectrometry analysis of thin tissue sections without the requirement of chemical labeling. The MSI generates chemically specific and spatially resolved ion distribution information for administered drugs and metabolites, which allows numerous applications for studies involving various stages of drug absorption, distribution, metabolism, excretion, and toxicity (ADMET). MSI-based pharmacokinetic imaging analysis provides a histological context and cellular environment regarding dynamic drug distribution and metabolism processes, and facilitates the understanding of the spatial pharmacokinetics …

Two Mechanisms Of Chromosome Fragility At Replication-Termination Sites In Bacteria, Qian Mei, Devon M Fitzgerald, Jingjing Liu, Jun Xia, John P Pribis, Yin Zhai, Ralf B Nehring, Jacob Paiano, Heyuan Li, Andre Nussenzweig, P J Hastings, Susan M Rosenberg

Faculty, Staff and Students Publications

Chromosomal fragile sites are implicated in promoting genome instability, which drives cancers and neurological diseases. Yet, the causes and mechanisms of chromosome fragility remain speculative. Here, we identify three spontaneous fragile sites in the Escherichia coli genome and define their DNA damage and repair intermediates at high resolution. We find that all three sites, all in the region of replication termination, display recurrent four-way DNA or Holliday junctions (HJs) and recurrent DNA breaks. Homology-directed double-strand break repair generates the recurrent HJs at all of these sites; however, distinct mechanisms of DNA breakage are implicated: replication fork collapse at natural replication …

A Pharmacokinetic Analysis Of Hemodialysis For Metformin-Associated Lactic Acidosis, Stephen A Harding, Rana Biary, Robert S Hoffman, Mark K Su, Mary Ann Howland

Faculty, Staff and Students Publications

OBJECTIVE: Although hemodialysis is recommended for patients with severe metformin-associated lactic acidosis (MALA), the amount of metformin removed by hemodialysis is poorly documented. We analyzed endogenous clearance and hemodialysis clearance in a patient with MALA.

METHODS: A 62-year-old man with a history of type II diabetes mellitus presented after several days of vomiting and diarrhea and was found to have acute kidney injury (AKI) and severe acidemia. Initial serum metformin concentration was 315.34 μmol/L (40.73 μg/mL) (typical therapeutic concentrations 1-2 μg/mL). He underwent 6 h of hemodialysis. We collected hourly whole blood, serum, urine, and dialysate metformin concentrations. Blood, urine, …

Trace Element Concentrations In Blood And Scute Tissues From Wild And Captive Hawaiian Green Sea Turtles (Chelonia Mydas), Katherine R Shaw, Jennifer M Lynch, George H Balazs, T Todd Jones, Jeff Pawloski, Marc R Rice, Amanda D French, Jing Liu, George P Cobb, David M Klein

Faculty, Staff and Students Publications

Sea turtles are exposed to trace elements through water, sediment, and food. Exposure to these elements has been shown to decrease immune function, impair growth, and decrease reproductive output in wildlife. This study compares trace element concentrations in green turtles in captivity at Sea Life Park Hawaii (n = 6) to wild green turtles in Kapoho Bay, HI (n = 5 to 7). Blood and scute samples were collected and analyzed for eleven elements via inductively coupled plasma-mass spectrometry (ICP-MS). Selenium was significantly greater (p < 0.05) in the blood of captive turtles compared to wild turtles, while V, Ni, and Pb were significantly greater in the blood of wild turtles. In scute, V, Cu, Se, and Cr were significantly greater in captive turtles, while As was significantly greater in wild turtles. Pelleted food fed to the captive turtles and representative samples of the wild turtle diet were analyzed via ICP-MS to calculate trophic transfer factors and daily intake values. Wild turtles had greater estimated daily intake than captive turtles for all elements except Cu and Se. Because captive turtles are fed a diet very different from their wild counterparts, captive turtles do not represent control or reference samples for chemical exposure studies in wild turtles. No toxic thresholds are known for sea turtles, but rehabilitation and managed care facilities should monitor sea turtle elemental concentrations to ensure the animals’ health.