Audrey E. McGowin

A method for reliable voluntary oral administration of a fixed dosage (mg/kg) of chronic daily medication to rats.

Stress can influence a number of physiological processes including adult neurogenesis, metabolism, cardiovascular function, immune function, neurophysiological function, endocrine function and inflammatory processes following injury. In testing drugs which may be used to treat various diseases or injuries, reducing stress associated with chronic drug delivery to animal models should then be an imperative, which led us to design a reliable voluntary oral drug delivery method. Various drug combinations were tested versus vehicle controls in four different rat stocks or strains (Wistar, Fisher, Long Evans and Sprague Dawley) with our voluntary oral delivery system. Oral medications were placed into a store-bought sugar cookie dough ball (∼4 g), thoroughly integrating the dry drugs with the dough. This method has worked consistently to deliver the medication (complete ingestion) in four different stocks or strains of rats, with reliabilities ranging from 98.6% to 100%. The percentage of rats in each stock or strain that have at any time during the study had incomplete ingestion of the drugs ranged from 1% in Sprague Dawley, approximately 4% in Wistar and Fisher, to approximately 16% in Long Evans. Both serum and brain samples were analysed for high-performance liquid chromatography (HPLC) detection of one of our administered drugs: 5 mg/kg fluoxetine. HPLC analysis shows that serum levels are detectable 2–4 h after ingestion, but not 24 h after ingestion. Brain samples however, showed detectable levels of both fluoxetine and norfluoxetine more than a week following ingestion of a single dose, with higher norfluoxetine levels seen following a month of daily administered drugs.

Genetic Barcoding of Marine Leeches ( Ozobranchus spp.) from Florida Sea Turtles and Their Divergence in Host Specificity

Ozobranchus margoi and Ozobranchus branchiatus are the only two species of marine turtle leeches (Ozobranchus spp.) known to inhabit the Atlantic coast of the United States and the Gulf of Mexico. In early reports of fibropapillomatosis (FP) in green turtles (Chelonia mydas), O. branchiatus was implicated as a vector in the transmission of Fibropapilloma‐associated turtle herpesvirus (FPTHV). It is imperative that the leech species be identified to elucidate the role Ozobranchus spp. may play in disease transmission. In this study, Ozobranchus branchiatus has been identified for the first time on a loggerhead (Caretta caretta) turtle, and the molecular data for this species is now available for the first time in GenBank. Both species of leeches were also found infecting a single C. mydas. Using morphological taxonomy combined with distance‐ and character‐based genetic sequence analyses, this study has established a DNA barcode for both species of Ozobranchus spp. leech and has shown it can be applied successfully to the identification of leeches at earlier stages of development when morphological taxonomy cannot be employed. The results suggest a different haplotype may exist for O. branchiatus leeches found on C. caretta versus C. mydas. Leech cocoon residue collected from a C. mydas was identified using the new method.

Supercritical fluid extraction of chlorpyrifos and 3,5,6-trichloro-2-pyridinol from garden compost.

A method was developed for the simultaneous supercritical carbon dioxide extraction of chlorpyrifos and its primary degradate, 3,5,6-trichloro-2-pyridinol (TCP), from garden compost. In situ derivatization with N,O-bis(trimethylsilyl)trifluoracetamide was necessary for extraction of TCP. Recoveries for TCP and chlorpyrifos were quantitative for spiked compost samples. Sodium chloride was used as the packing material in extractions with in situ derivatization. Optimum results were obtained for air-dried samples containing 4-7% moisture. No sample cleanup was required prior to analysis by GC-flame ionization detection. The effects of compost moisture content and ageing were investigated for chlorpyrifos recovery. No significantly negative effect on recovery for up to 20% (w/w) moisture for chlorpyrifos was observed. Effects of ageing showed a decrease in extraction efficiency over time with 52% recovery after 10 days.

Selectivity of 1,3-dipolar cycloaddition of methyl propiolate to 3-phenylsydnone in near- or supercritical carbon dioxide

Abstract The selectivity of the 1,3-dipolar cycloaddition reaction of methyl propiolate to 3-phenylsydnone was measured under various conditions of pressure (7.6–30.4 MPa) and temperature (333–423 K) in near- or supercritical carbon dioxide. The reaction produces a mixture of two regioisomers, 3-carbomethoxy-1-phenylpyrazole (isomer A) and 4-carbomethoxy-1-phenylpyrazole (isomer B). Reaction composition was measured by high-performance liquid chromatography (HPLC). A supercritical fluid extraction (SFE) instrument, programmed in the static mode, was used as the reaction apparatus. The selectivity (isomer A/isomer B) of the reaction was compared with the selectivity in toluene at 353 K. For both solvents, selectivity did not vary over time for up to 12 h in CO2 and 67 h in toluene. The mean selectivity measured in toluene was 3.62 compared with 5.08 in CO2. At 7.6 MPa and 1 h in CO2, the selectivity decreased with increasing temperature from 5.52 at 353 K to 3.14 at 423 K. At 353 K and 3 h, the selectivity increased with increasing pressure from 4.96 at 7.6 MPa to 6.56 at 30.4 MPa, however, the yield decreased by 50%. Overall, lower pressure and higher temperature gave higher yields while higher pressure and lower temperature produced greater selectivity of isomer A over isomer B.

Examining the reversibility of long-term behavioral disruptions in progeny of maternal SSRI exposure

Visual Abstract Serotonergic dysregulation is implicated in numerous psychiatric disorders. Serotonin plays widespread trophic roles during neurodevelopment; thus perturbations to this system during development may increase risk for neurodevelopmental disorders. Epidemiological studies have examined association between selective serotonin reuptake inhibitor (SSRI) treatment during pregnancy and increased autism spectrum disorder (ASD) risk in offspring. It is unclear from these studies whether ASD susceptibility is purely related to maternal psychiatric diagnosis, or if treatment poses additional risk. We sought to determine whether maternal SSRI treatment alone or in combination with genetically vulnerable background was sufficient to induce offspring behavior disruptions relevant to ASD. We exposed C57BL/6J or Celf6 +/- mouse dams to fluoxetine (FLX) during different periods of gestation and lactation and characterized offspring on tasks assessing social communicative interaction and repetitive behavior patterns including sensory sensitivities. We demonstrate robust reductions in pup ultrasonic vocalizations (USVs) and alterations in social hierarchy behaviors, as well as perseverative behaviors and tactile hypersensitivity. Celf6 mutant mice demonstrate social communicative deficits and perseverative behaviors, without further interaction with FLX. FLX re-exposure in adulthood ameliorates the tactile hypersensitivity yet exacerbates the dominance phenotype. This suggests acute deficiencies in serotonin levels likely underlie the abnormal responses to sensory stimuli, while the social alterations are instead due to altered development of social circuits. These findings indicate maternal FLX treatment, independent of maternal stress, can induce behavioral disruptions in mammalian offspring, thus contributing to our understanding of the developmental role of the serotonin system and the possible risks to offspring of SSRI treatment during pregnancy.