A case of feline intoxication and fatality with the illicit drug heroin is described. A 5-year-ol... more A case of feline intoxication and fatality with the illicit drug heroin is described. A 5-year-old castrated male domestic shorthair cat was recently diagnosed with an active pneumonitis and left at home for a couple of days under the care of another resident. Upon return, the owner found his cat dead with strong suspicion of foul play. The cat was necropsied by a local veterinary clinic to retrieve the liver for diagnostic toxicology. The postmortem liver sample screened positive for 6-acetylmorphine and 6-acetylcodeine by gas chromatography mass spectrometry. Deconvolution techniques were applied to chromatograms, which revealed the additional presence of morphine and mirtazapine. Subsequent quantitation of mirtazapine, heroin, morphine, 6-acetylmorphine and 6-acetylcodeine was performed by gas chromatography--tandem quadrupole mass spectrometry. Although companion animal fatalities arising from toxicities are a likely consequence of drug abuse in a home, this is the first reporte...
OBJECTIVE To determine the pharmacokinetics of voriconazole after single IV or orally administere... more OBJECTIVE To determine the pharmacokinetics of voriconazole after single IV or orally administered boluses in common ravens (Corvus corax). ANIMALS 8 healthy common ravens. PROCEDURES Voriconazole (5 mg/mL, 10 mg/kg IV) was administered to 8 birds, and then plasma voriconazole concentrations were measured at various time points by high-pressure liquid chromatography with mass spectrometry. Starting 6 months later in a randomized 3-treatment 3-period regimen, birds received a single oral dose of voriconazole suspension (10 mg/mL; 6, 12, and 24 mg/kg PO). The study period was May 2015 to March 2016. RESULTS Voriconazole (10 mg/kg IV) achieved an initial plasma concentration of 6.31 µg/mL when measured over 21 hours. After oral administration of voriconazole at 6, 12, and 24 mg/kg, the relative bioavailability was 67.5%, 209%, and 183%, respectively. For the 6-mg/kg dose, the maximum plasma concentration was reached at 30 minutes after administration and remained in the therapeutic ran...
Supplemental material, sj-pdf-1-ems-10.1177_14690667211000244 for Vitamin D analyses in veterinar... more Supplemental material, sj-pdf-1-ems-10.1177_14690667211000244 for Vitamin D analyses in veterinary feeds by gas chromatography-tandem mass spectrometry by Andreas Lehner, Margaret Johnson, Alan Zimmerman, Justin Zyskowski and John Buchweitz in European Journal of Mass Spectrometry
Tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) are perennial cool-seas... more Tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) are perennial cool-season grasses which are infected with the endophytic fungi, Neotyphodium coenophialum and N. lolii, respectively. These endophytes have been increasingly selected for, as they confer benefits such as pest resistance and drought tolerance to the plant. However, livestock grazing endophyte-infected (E+) grasses are negatively impacted by fungal ergot and lolitrem alkaloids, which are responsible for a variety of mammalian diseases including fescue toxicosis (summer syndrome, fescue foot and fat necrosis) and ryegrass staggers. Most likely, not all of the ergot alkaloids involved in fescue toxicosis have been identified to date. During sample processing for the diagnostic analysis of the endophyte toxin ergovaline, other unidentified peaks occasionally elute that appear to coincide with clinical disease. Analysis of unidentified chromatographic peaks was performed on feed samples by LCMS/ MS t...
As part of our efforts to understand factors influencing chromosomal organization and rearrangeme... more As part of our efforts to understand factors influencing chromosomal organization and rearrangements, we studied a family of Salmonella typhimurium tandum duplication mutants. We found that the duplications were originally generated by unequal recombination between pairs of similarly oriented ribosomal ribonucleic acid operons (rrn). This demonstration involved the physical isolation of the duplicated material as circular deoxyribonucleic acid excised from the duplication. The four rrn operons involved embraced the ilv pur D segment of the chromosome and occurred at positions closely analogous to those previously observed for Escherichia coli. The interval between rrnC and rrnA of S. typhimurium was similar in size to that of E. coli (43 versus 39 kilobases), as was the interval between rrnB and rrnE (94 versus 91 kilobases). The rrnA-to-rrnB interval of S. typhimurium, however, was 155 kilobases, substantially greater than the 126 kilobases observed for E. coli.
The complete nucleotide sequence of the rhsA locus and selected portions of other members of the ... more The complete nucleotide sequence of the rhsA locus and selected portions of other members of the rhs multigene family of Escherichia coli K-12 have been determined. A definition of the limits of the rhsA and rhsC loci was established by comparing sequences from E. coli K-12 with sequences from an independent E. coli isolate whose DNA contains no homology to the rhs core. This comparison showed that rhsA comprises 8,249 base pairs (bp) in strain K-12 and that the Rhs0 strain, instead, contains an unrelated 32-bp sequence. Similarly, the K-12 rhsC locus is 9.6 kilobases in length and a 10-bp sequence resides at its location in the Rhs0 strain. The rhsA core, the highly conserved portion shared by all rhs loci, comprises a single open reading frame (ORF) 3,714 bp in length. The nucleotide sequence of the core ORF predicts an extremely hydrophilic 141-kilodalton peptide containing 28 repeats of a motif whose consensus is GxxxRYxYDxxGRL(I or T). One of the most novel aspects of the rhs f...
The Science of the total environment, Jan 15, 2017
Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Docum... more Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Documented effects of contaminants include potential disease progression and adverse impacts on development, immune function, and survival in these imperiled species. The shallow seagrass habitats of Florida's northwest coast (Big Bend) serve as an important developmental habitat for Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles; however, few studies have been conducted in this area. Our objectives were (1) to evaluate plasma analytes (mass, minimum straight carapace length, body condition index [BCI], fibropapilloma tumor score, lysozyme, superoxide dismutase, reactive oxygen/nitrogen species, plasma protein electrophoresis, cholesterol, and total solids) in Kemp's ridleys and green turtles and their correlation to brevetoxins that were released from a red tide bloom event from July-October 2014 in the Gulf of Mexico near Florida's Big Bend, and (...
A case of feline intoxication and fatality with the illicit drug heroin is described. A 5-year-ol... more A case of feline intoxication and fatality with the illicit drug heroin is described. A 5-year-old castrated male domestic shorthair cat was recently diagnosed with an active pneumonitis and left at home for a couple of days under the care of another resident. Upon return, the owner found his cat dead with strong suspicion of foul play. The cat was necropsied by a local veterinary clinic to retrieve the liver for diagnostic toxicology. The postmortem liver sample screened positive for 6-acetylmorphine and 6-acetylcodeine by gas chromatography mass spectrometry. Deconvolution techniques were applied to chromatograms, which revealed the additional presence of morphine and mirtazapine. Subsequent quantitation of mirtazapine, heroin, morphine, 6-acetylmorphine and 6-acetylcodeine was performed by gas chromatography--tandem quadrupole mass spectrometry. Although companion animal fatalities arising from toxicities are a likely consequence of drug abuse in a home, this is the first reporte...
OBJECTIVE To determine the pharmacokinetics of voriconazole after single IV or orally administere... more OBJECTIVE To determine the pharmacokinetics of voriconazole after single IV or orally administered boluses in common ravens (Corvus corax). ANIMALS 8 healthy common ravens. PROCEDURES Voriconazole (5 mg/mL, 10 mg/kg IV) was administered to 8 birds, and then plasma voriconazole concentrations were measured at various time points by high-pressure liquid chromatography with mass spectrometry. Starting 6 months later in a randomized 3-treatment 3-period regimen, birds received a single oral dose of voriconazole suspension (10 mg/mL; 6, 12, and 24 mg/kg PO). The study period was May 2015 to March 2016. RESULTS Voriconazole (10 mg/kg IV) achieved an initial plasma concentration of 6.31 µg/mL when measured over 21 hours. After oral administration of voriconazole at 6, 12, and 24 mg/kg, the relative bioavailability was 67.5%, 209%, and 183%, respectively. For the 6-mg/kg dose, the maximum plasma concentration was reached at 30 minutes after administration and remained in the therapeutic ran...
Supplemental material, sj-pdf-1-ems-10.1177_14690667211000244 for Vitamin D analyses in veterinar... more Supplemental material, sj-pdf-1-ems-10.1177_14690667211000244 for Vitamin D analyses in veterinary feeds by gas chromatography-tandem mass spectrometry by Andreas Lehner, Margaret Johnson, Alan Zimmerman, Justin Zyskowski and John Buchweitz in European Journal of Mass Spectrometry
Tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) are perennial cool-seas... more Tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) are perennial cool-season grasses which are infected with the endophytic fungi, Neotyphodium coenophialum and N. lolii, respectively. These endophytes have been increasingly selected for, as they confer benefits such as pest resistance and drought tolerance to the plant. However, livestock grazing endophyte-infected (E+) grasses are negatively impacted by fungal ergot and lolitrem alkaloids, which are responsible for a variety of mammalian diseases including fescue toxicosis (summer syndrome, fescue foot and fat necrosis) and ryegrass staggers. Most likely, not all of the ergot alkaloids involved in fescue toxicosis have been identified to date. During sample processing for the diagnostic analysis of the endophyte toxin ergovaline, other unidentified peaks occasionally elute that appear to coincide with clinical disease. Analysis of unidentified chromatographic peaks was performed on feed samples by LCMS/ MS t...
As part of our efforts to understand factors influencing chromosomal organization and rearrangeme... more As part of our efforts to understand factors influencing chromosomal organization and rearrangements, we studied a family of Salmonella typhimurium tandum duplication mutants. We found that the duplications were originally generated by unequal recombination between pairs of similarly oriented ribosomal ribonucleic acid operons (rrn). This demonstration involved the physical isolation of the duplicated material as circular deoxyribonucleic acid excised from the duplication. The four rrn operons involved embraced the ilv pur D segment of the chromosome and occurred at positions closely analogous to those previously observed for Escherichia coli. The interval between rrnC and rrnA of S. typhimurium was similar in size to that of E. coli (43 versus 39 kilobases), as was the interval between rrnB and rrnE (94 versus 91 kilobases). The rrnA-to-rrnB interval of S. typhimurium, however, was 155 kilobases, substantially greater than the 126 kilobases observed for E. coli.
The complete nucleotide sequence of the rhsA locus and selected portions of other members of the ... more The complete nucleotide sequence of the rhsA locus and selected portions of other members of the rhs multigene family of Escherichia coli K-12 have been determined. A definition of the limits of the rhsA and rhsC loci was established by comparing sequences from E. coli K-12 with sequences from an independent E. coli isolate whose DNA contains no homology to the rhs core. This comparison showed that rhsA comprises 8,249 base pairs (bp) in strain K-12 and that the Rhs0 strain, instead, contains an unrelated 32-bp sequence. Similarly, the K-12 rhsC locus is 9.6 kilobases in length and a 10-bp sequence resides at its location in the Rhs0 strain. The rhsA core, the highly conserved portion shared by all rhs loci, comprises a single open reading frame (ORF) 3,714 bp in length. The nucleotide sequence of the core ORF predicts an extremely hydrophilic 141-kilodalton peptide containing 28 repeats of a motif whose consensus is GxxxRYxYDxxGRL(I or T). One of the most novel aspects of the rhs f...
The Science of the total environment, Jan 15, 2017
Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Docum... more Natural biotoxins and anthropogenic toxicants pose a significant risk to sea turtle health. Documented effects of contaminants include potential disease progression and adverse impacts on development, immune function, and survival in these imperiled species. The shallow seagrass habitats of Florida's northwest coast (Big Bend) serve as an important developmental habitat for Kemp's ridley (Lepidochelys kempii) and green (Chelonia mydas) sea turtles; however, few studies have been conducted in this area. Our objectives were (1) to evaluate plasma analytes (mass, minimum straight carapace length, body condition index [BCI], fibropapilloma tumor score, lysozyme, superoxide dismutase, reactive oxygen/nitrogen species, plasma protein electrophoresis, cholesterol, and total solids) in Kemp's ridleys and green turtles and their correlation to brevetoxins that were released from a red tide bloom event from July-October 2014 in the Gulf of Mexico near Florida's Big Bend, and (...
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