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Toxicity mechanisms of per- and polyfluoroalkyl substances (PFASs), a chemical class present in diverse ecosystems, as well as many of their precursors, have been increasingly characterized in aquatic species. Perfluorooctanesulfonamide (PFOSA, C8H2F17NO2S) is a common precursor of perfluorooctane sulfonic acid (PFOS), a long-chain PFAS. Here, we assessed sub-lethal endpoints related to development, oxidative stress, transcript levels, and distance moved in zebrafish embryos and larvae following continuous exposure to PFOSA beginning at 6 h post-fertilization (hpf). PFOSA decreased survival in fish treated with 1 µg/L PFOSA; however, the effect was modest relative to the controls (difference of 10%). Exposure up to 10 µg/L PFOSA did not affect hatch rate, nor did it induce ROS in 7-day-old larvae fish. The activity of larval fish treated with 100 µg/L PFOSA was reduced relative to the solvent control. Transcripts related to oxidative stress response and apoptosis were measured and BCL2-associated X, apoptosis regulator (bax), cytochrome c, somatic (cycs), catalase (cat), superoxide dismutase 2 (sod2) were induced with high concentrations of PFOSA. Genes related to neurotoxicity were also measured and transcript levels of acetylcholinesterase (ache), elav-like RNA binding protein 3 (elavl3), growth-associated protein 43 (gap43), synapsin II (syn2a), and tubulin 3 (tubb3) were all increased in larval fish with higher PFOSA exposure. These data improve our understanding of the potential sub-lethal toxicity of PFOSA in fish species. [ABSTRACT FROM AUTHOR]

Background and objective: Emergence agitation is a common phenomenon in children recovering from general anesthesia. An emergence agitation reaction increases the risk of injuring the surgical repair, the patient, and the caregivers. Thus, we aim to explore the efficacy of melatonin premedication on emergence agitation in children undergoing herniorrhaphy surgeries. Patients and methods: A randomized prospective triple-blinded trial was conducted on 117 children with herniorrhaphy surgeries conducted at the Anesthesia, ICU, and Pain Management Department, Menoufia University hospitals from April 2022 to July 2023. Results: Yale preoperative scale at the start did not significantly differ among the studied groups (P>0.05). However, the Yale preoperative scale at 1 was significantly higher in group 1 with a mean of 10.2±1.9 than in group 2 (9.5±1.4) and group 3 (5.9±1.4) (P<0.001). The agitation score at 5 h was significantly higher among group 1 with a mean of 2.77±0.67 than group 2 (2.56±0.64) and group 3 (2.03 ±0.96) (P<0.001). Also, agitation scores at 10 and 15 h were significantly higher in group 1 (3.36±0.63, 4.2±0.66) than in group 2 (3.2±0.66, 3.79±0.73) and group 3 (1.74±0.88, 2.03±1.04), respectively (P<0.001). Conclusion: Melatonin premedication decreased the agitation scale postoperatively. The decrease was significantly higher in high doses in preventing emergence agitation in children. High-dose melatonin compared with low dose might have a significant effect in preventing emergence agitation. [ABSTRACT FROM AUTHOR]

Purpose To assess the use of oral chloral hydrate (CH) sedation in uncooperative children to perform a precise cycloplegic retinoscopy and a thorough dilated fundus examination in an outpatient strabismus and nystagmus clinic. Patients and methods A prospective study was conducted on 114 uncooperative children (119 sedation episodes) who were attending the strabismus and nystagmus outpatient clinic at Menoufia University Hospital. Children were sedated by the first dose of CH (50 mg/kg). A second dose, half-strength of the first dose, was given if no adequate sedation occurred after 30 min. The degree of sedation was graded into five categories: excellent, good, fair, poor, and failure. All demographic characteristics, sedation success, failure, and adverse events were reported and statistically analyzed. Results The mean age of children was 23.38 months (range: 5.16–62.06), and their weight ranged from 6.5 to 22 kg. The total CH dose ranged from 325 to 1500 mg. A total of 78 sedation episodes were reported by a single dose, and 41 by two doses. The percentage of the grade of sedation in our 119 episodes was as follows: excellent (56.3%), good (9.2%), fair (28.6%), poor (2.5%), and failure (3.4%). The overall success of one dose was 65.5%, which increased to 96.6% by a second supplemental dose. The most common complication was vomiting (13.4%). Other complications included prolonged drowsiness (one case) and paradoxical agitation (two cases). Spearman correlation showed a significant positive correlation between the degree of sedation and the total dose of CH (r=0.603, P<0.001). Conclusion According to our study, the use of CH was found to have a high success rate with two doses, without major adverse events. [ABSTRACT FROM AUTHOR]

R3858 --> There are two sources of hydroxylated bromodiphenyl ethers in aquatic environments, biotransformation products of bromodiphenyl ether (BDE) flame retardants, and natural products biosynthesized by marine bacteria. Regardless of source, BDEs and their hydroxylated metabolites (OH‐BDEs) are lipophilic molecules that can bioaccumulate in animals. OH‐BDEs are potential substrates for glucuronidation and sulfonation, as demonstrated with human liver samples (Cisneros et. al. Chemosphere, 226, 132‐139, 2019). The objective of the present study was to determine how well fish can eliminate selected OH‐BDEs by glucuronidation. The four OH‐BDEs studied here were natural products, 4‐OH‐BDE47, 2'‐OH‐BDE68, 6‐OH‐2'MeO‐BDE68 or closely related to natural products, 4'‐OH‐BDE68. Liver microsomes were prepared from laboratory‐maintained adult Channel Catfish, Ictalurus punctatus, two females and one male, held in freshwater tanks, and from wild‐caught adult Red Snapper, Lutjanus campechanus, from the Gulf of Mexico, two females and two males. To determine rates of glucuronidation, uridine‐diphosphate‐14C‐glucuronic acid (UDPGA), 1 mM, was incubated with liver microsomes, 0.05 mg, in the presence of 0.1M Tris‐Cl buffer, pH 7.6, magnesium chloride, 5 mM, and varying concentrations of OH‐BDE, 2.5 to 50 µM for 5 min. The amount of protein and incubation time were determined from preliminary studies to show linear formation of the glucuronide products. After 5 min, reactions were stopped by addition of tetrabutylammonium dihydrogen phosphate and acetic acid, and the ion‐pair of the glucuronide was extracted into ethyl acetate for determination of 14C, following a previously published procedure. In both fish species, the rates of glucuronidation with increasing substrate concentration followed Michaelis‐Menten kinetics. The Km values for the OH‐BDEs ranged from 3 to 35 µM and were generally somewhat lower in the catfish than the red snapper, though this only reached statistical significance, p<0.05, for 2'‐OH‐BDE68. Vmax values ranged from 0.9 to 5.4 nmol glucuronide per min per mg protein and for each substrate were variable between individual fish. Mean glucuronidation enzyme efficiency was highest for 2'‐OH‐BDE68 in the channel catfish, 715 ± 119 µL.min‐1.mg‐1 (mean ± S.D., n = 3), significantly higher than for red snapper, 239 ± 74 µL.min‐1.mg‐1 (n=4). The lowest glucuronidation efficiencies were found for 6‐OH‐BDE47, 145 ± 57 µL.min‐1.mg‐1, n=3 in Channel Catfish and 68 ± 37 µL.min‐1.mg‐1, n=4, in Red Snapper. Because of the variability, the efficiencies of 6‐OH‐BDE47 glucuronidation were similar between the two species. The glucuronidation efficiencies reported here for two fish species are of similar orders of magnitude to those observed with human liver microsomes. Both fish species were able to efficiently catalyze glucuronidation of the studied OH‐BDEs, suggesting these compounds should be readily excreted from exposed Channel Catfish or Red Snapper. [ABSTRACT FROM AUTHOR]