Effects of weathered polyethylene microplastic ingestion on sexual maturation, fecundity and egg quality in maturing broodstock Atlantic cod Gadus morhua.

Microplastics (MPs) have become a global issue as they are omnipresent in the ocean. Fish ingesting MPs through feed could be affected in their physiological function, e.g., disrupted enzyme production and function, reduction of feeding and reproductive failure. This study assessed the effects of feed containing naturally weathered MPs from the Oslofjord (Norway) on the reproductive physiology of Atlantic cod (Gadus morhua). Farmed cod broodstock were fed either control (C-diet) or feeds containing 1% microplastic (MP-diet) starting nine months prior to spawning, from June until May. No major differences were found between diet groups in overall biometrics or gonad histology. Sex steroid levels (testosterone, 11-ketotestosterone and 17ß-estradiol) resulted in expected profiles increasing over time without any significant differences between treatments. Gene expression levels of the steroidogenic enzyme 20ß-hydroxysteroid dehydrogenase (20ß-hsd) and vitellogenin1 (vtg1) showed significant differences between dietary treatments with lower expression in the control group. This can be a direct effect of MPs, but endocrine disrupting effects of potentially leachable plastic additives cannot be completely ruled out. Thus, these enzymes could be indicators of exposure to contaminants that disrupt sexual maturation by affecting the production of primarily maturation-inducing steroid. Although the concentration of MPs employed in this study may not be high enough to elicit any observable short-term biological effects, the observed gene expression suggests that long-term consequences should be considered caused by an expected increase of MPs in marine environments.

Effect of cisapride on relapse of reflux oesophagitis, healed with an antisecretory drug.

Maintenance treatment with cisapride was evaluated in 298 patients in whom reflux oesophagitis had been healed with antisecretory drugs. Initially, 34% of the patients had grade-I oesophagitis, 33% had grade II, and 33% had grade III. The patients were treated with 20 mg cisapride twice daily or placebo for 6 months or until endoscopic relapse was shown if this occurred earlier. Survival analysis showed that cisapride significantly prolonged the time to endoscopic relapse in grade-I patients (P = 0.02). The intergroup difference in symptomatic relapse in all patients was also significant (P = 0.010). The effect of cisapride was less clearcut in grade II or III, and/or in patients healed with omeprazole. Factors associated with early relapse were placebo therapy, prior omeprazole therapy, duration of pre-trial symptomatic period, and initial endoscopic severity grade. Adverse experiences were limited; diarrhoea was reported by 9% of the cisapride patients.