Toxicoproteomics in diagnostic toxicology

Elsevier eBooks · 2025-01-01

Contributors

Elsevier eBooks · 2025-01-01

Toxicology and Analytical Chemistry

Veterinary Clinics of North America Food Animal Practice · 2023 · 4 citations

• Toxicology
• Medicine
• Biology

GC/MS Method for the Detection of Terbufos, Diazinon and Parathion in Blood v1

2022-12-01 · 1 citations

Scope This is a multi-residue method for the detection of the organophosphate pesticides, terbufos, diazinon and parathion in blood by gas chromatography and mass spectrometry (GC/MS). This is a qualitative screening method intended to isolate and concentrate organophosphate pesticides from sample extracts for GC/MS confirmation. This method also allows for adequate separation and detection of 42 other organophosphorus, carbamate and organochlorine pesticides. In this multi-residue method, pesticides are extracted from blood samples in acetonitrile and isolated using a dual-layer, ENVI-Carb-II‱/PSA solid-phase extraction procedure. The pesticides are subsequently separated and detected using gas chromatography and detected using electron-impact mass spectrometry. Table 1. Instrument and Method Limits of Detection Method validation/evaluation/verification: In-house method validation data and evaluation by an independent laboratory (Vet-LIRN) in collaborative multi-laboratory studies

Genomic and proteomic mechanisms and models in toxicity and safety evaluation of nutraceuticals

Elsevier eBooks · 2021-01-01 · 1 citations

Atrazine intoxication in cattle, confirmed by gas chromatography–mass spectrometry

Journal of Veterinary Diagnostic Investigation · 2021 · 2 citations

• Chemistry
• Chromatography
• Animal science

Ten of 40 cows died within 48 h of gaining access to a barn in which various chemicals were stored. Some of the surviving cows exhibited drooling, muscle tremors, and agitation. Postmortem examinations of 2 cows were performed in the field, and revealed nonspecific, moderate-to-severe pulmonary congestion. Liver and rumen contents, each from a different cow, were analyzed using a qualitative, multi-residue GC-MS method validated for the detection of pesticides and other chemical analytes. Using this method, extracts from the liver and rumen content samples were compared to atrazine (neat standard) and matrix-matched, control samples fortified with atrazine. GC-MS analysis detected atrazine at 215 m/z (NIST match >97%) with a retention time of ~13 min in liver and rumen content samples from our case. Detection of atrazine in the samples from the cows in this herd, combined with the clinical history, indicate that atrazine toxicity was the likely cause of clinical signs and death observed in this herd.

Chronic copper toxicosis in a crossbred heifer calf

Journal of Veterinary Diagnostic Investigation · 2020 · 8 citations

• Pathology
• Chemistry
• Biology

An 8-mo-old, crossbred, heifer calf was presented to the Heeke Animal Disease Diagnostic Laboratory with a history of ataxia and altered mentation. Grossly, the liver was diffusely yellow-orange, turgid, and exuded watery, thin blood on cut section. The cortex and medulla in both kidneys were diffusely and markedly dark brown to black. The urinary bladder was filled with dark red urine. Histologically, centrilobular hepatocellular degeneration was observed, but these sections lacked necrosis. In the kidney, numerous cortical tubules contained intraluminal bright eosinophilic fluid and red-orange granular casts that stained positive for hemoglobin with the Dunn-Thompson method. The gross and histologic lesions supported a high level of suspicion for copper toxicosis. Feed and water samples from the farm were submitted for mineral analysis. The copper concentration in the feed was 118 mg/kg, and the molybdenum concentration was 0.9 mg/kg. Chronic copper toxicosis is rarely reported in cattle. The gross lesions in our case are a departure from, although similar to, previously reported cases, including lack of histologic hepatocellular necrosis. Collectively, gross and histologic lesions were compatible with copper toxicosis in this calf, and copper concentrations in the feed samples suggest a feed-mixing error.

Proteomics in Biomarkers of Chemical Toxicity

Elsevier eBooks · 2019-01-01 · 7 citations

Proteomics in the Evaluation of Nutraceuticals and Functional Foods

2019-01-01 · 4 citations

Filter Cone Spray Ionization Coupled to a Portable MS System: Application to On-Site Forensic Evidence and Environmental Sample Analysis

Journal of the American Society for Mass Spectrometry · 2019-12-31 · 38 citations

The complexity of field-borne sample matrices and the instrumental constraints of portable mass spectrometers (MS) often necessitate that preparative steps are added prior to ambient MS methods when operated on-site, but the corresponding decrease in throughput and experimental simplicity can make field operation impractical. To this end, we report a modified ambient MS method, filter cone spray ionization (FCSI), specifically designed for simple, yet robust, processing of bulk forensic evidence and environmental samples using a fieldable MS system. This paper-crafted source utilizes low-cost laboratory consumables to produce a conical structure that serves as a disposable, spray-based ionization source. Integrated extraction and filtration capabilities mitigate sample heterogeneity and carryover concerns and expedite sample processing, as characterized through the analysis of a variety of authentic forensic evidence types (e.g., abused pharma tablets, counterfeit/adulterated tablets, crystal-based drugs, synthetic marijuana, toxicological specimens) and contaminated soil samples. The data presented herein suggests that the FCSI-MS design could prove robust to the rigors of field-borne, bulk sample screening, overcoming the inefficiencies of other ambient MS methods for these sample classes. Novel applications of FCSI-MS are also examined, such as the coupling to trace evidence vacuum filtration media.