Diclofenac-induced cytotoxicity in cultured carp leukocytes

Temperature-dependent in vitro hepatocytotoxicity of insecticides in bats

Heterothermic insectivorous bats are supposed to experience differential adverse effects of insecticidal pollutants depending on their seasonal and/or daily variation of metabolic and detoxification rates. Here, we investigated effects of imidacloprid, cypermethrin and fipronil on Nyctalus noctula bat-derived hepatocytes through cytotoxicity, cell inhibition and death at different concentrations (0.01, 0.1, 1, 10, 100, 1000 μg/ml), exposure times (10, 24, 48 hrs), incubation temperatures simulating hibernation (8 °C), daily torpor (20 °C), normothermy (37 °C) and active flight (40 °C), and cytochrome P450 addition. Toxic effects were significantly influenced by temperature (p < 0.05), with strong cytotoxicity after 10 hour exposure to fipronil or cypermethrin at 37 and 40 °C, cell replication inhibition (all insecticides at 8 °C) and cellular stimulation, with slight culture proliferation after 48 hours (all insecticides at 40 °C). Replacing protected chiropterans with cell cultures is a way to assess and extrapolate risks of insecticides for bats.

Leftover of Amoxicillin Suspension After Use by Children in the Netherlands

PURPOSE

In clinical practice, a discrepancy may exist between the prescribed amount of a drug and the commercially available pack sizes in the pharmacy, potentially contributing to drug waste. This study aimed-as an example of this phenomena-to quantify leftover of amoxicillin suspension prescribed to children, due to discrepancies between physician-prescribed and pharmacy-dispensed amounts.

METHODS

We performed a retrospective cohort study including amoxicillin suspension dispensations for patients aged 0-12 years between 2017 and 2019 utilizing the Dutch PHARMO database. Leftover amount of amoxicillin was estimated by assessing the discrepancy between the prescribed and dispensed amounts. Extrapolated amoxicillin weight and economic spillage estimates for the Netherlands were determined. The impact of two theoretical interventions on leftover amount was assessed: (1) introducing vials with half the volume of the current 100 and 30 mL vials and (2) a combination of the first intervention with a maximum of 10% round-down by the dispensing pharmacy of the prescribed dose.

RESULTS

We included 79 512 amoxicillin suspension dispensations for 62 252 patients. The mean leftover amount of amoxicillin suspension per dispensing was 27%. The yearly amount of amoxicillin leftover was 49.8 kg in the study cohort, equivalent to yearly 633 kg and €621 000 when extrapolated to the Netherlands. Employing the first theoretical intervention reduced the mean leftover per dispensing to 20%, reducing the yearly leftover to 31.6 kg amoxicillin in the study cohort, and to 400 kg and €400 000 extrapolated. The second theoretical intervention further reduced leftover to 17%, reducing the yearly leftover to 24.3 kg amoxicillin in the study cohort, and to 300 kg and €300 000 extrapolated.

CONCLUSION

Approximately a quarter of amoxicillin suspension remains as leftover per dispensing. Applying different theoretical intervention shows the potential for a significant reduction of amoxicillin leftover.

Torpor/hibernation cycle may enhance the risk of insecticides for bats: an in vitro study

Exposure to pollutants is considered one of the potential reasons of population declines in bats. In the context of previous studies, we managed to create and keep a wide collection of cell lines from European bat species. Liver cells were chosen for testing, as they represent the preferred model for toxicological studies. Bats are protected, cell lines replacing experimental animals thus represent a unique opportunity to examine effects of pollutants which animals are exposed to in their environments. Moreover, cell incubation temperature variation may simulate physiological states of heterothermic bats. Liver cell lines were cultivated to the required cell number. Exposure to five different concentrations of permethrin (PM) and imidacloprid (IMI) were used to determine cytotoxic effects of these pesticides on Nyctalus noctula-derived liver cells cultivated at 37 °C and 8 °C for 24 h. An assay based on the measurement of activity of lactate dehydrogenase released from damaged cells was used for quantitating cytotoxicity. Cytotoxicity of IMI ranged from 0% to 47% and from 56% to 67% at 37 °C and 8 °C, respectively. Cytotoxicity of PM ranged from 36% to 56% and from 43% to 88% at 37 °C and 8 °C, respectively. Permethrin was tested on the cells at an order of magnitude lower concentrations; even so, higher degree of cytotoxicity was recorded. Imidacloprid was more toxic to bat liver cells at a hibernation temperature than at body temperature of 37 °C.