Diclidophora luscae (Monogenea: Diclidophoridae) in pouting, Trisopterus luscus (Linnaeus, 1758) from the northeast Atlantic; epidemiology, morphology, molecular and phylogenetic analysis

Diclidophora (Monogenea) species are gill parasites with a stenoxenic specificity occurring only in Gadiformes. Epidemiological, morphological, molecular and phylogenetic studies were performed on 594 Diclidophora specimens collected from 213 Trisopterus luscus captured in the northeast Atlantic off the Portuguese coast during 2012, 2013 and 2020. Prevalence, parasite abundance and infection intensity were determined. Positive correlation between fish weight and length and infection intensity was observed. The effects of preservation on the parasite morphological features were studied, highlighting that specimen's identification should be reinforced by molecular studies. A sequence of D. luscae capelanii from T. capelanus captured in the Mediterranean Sea included in the 28S rDNA molecular analysis was nested within a robust D. luscae clade. Data analysis suggested that this species is in fact D. luscae, which is compatible with T. luscus and T. capelanus. The identity of fish hosts was confirmed by barcoding. For the first time, data on the infection parameters is shown, highlighting the importance of including this parasite in the monitoring plans for a holistic approach with possible effects for the management of pouting resources aiming of attaining sustainable development and biodiversity conservation measures, according to the 14th objective of the 2030 agenda.

Effect of doses of glucagon used to treat food impaction on esophageal motor function of normal subjects

We studied 10 normal subjects to determine the effect of doses of intravenous glucagon used to treat food impaction on esophageal motor function. With a multilumen assembly perfused by a low compliance pneumohydraulic infusion pump, esophageal manometry was performed during baseline and after randomized administration of 0. 25, 0.5, and 1 mg intravenous glucagon. Mean proximal and distal amplitudes of contraction, proximal and distal amplitude of contraction duration, lower esophageal sphincter (LES) resting pressure, percentage of LES relaxation, and glucagon-related side effects were evaluated. No effect on proximal amplitude of contraction and proximal or distal esophageal contraction duration was noted. Mean amplitude of contraction in the distal esophagus was further reduced with increased dosage of glucagon but did not achieve statistical significance. Mean LES resting pressure was significantly reduced after 0.25 mg (18.7 +/- 1.8 vs. 10.2 +/- 1.5 mmHg, p = 0.0001) and further reduced after 0.5 mg (5.9 +/- 1.2 mmHg, p = 0.0009). Mean LES relaxation was significantly reduced after 0. 25 mg (93.1 +/- 2.4% vs. 63.6 +/- 8.8%, p = 0.0031). The 1-mg dose versus the 0.5-mg did not provide further reduction in any LES function parameters. One subject experienced transient nausea after 0.5 mg, and 4 subjects experienced nausea after 1 mg glucagon. In conclusion, increased doses of glucagon further reduce mean distal esophageal amplitude of contraction. Although maximum reduction in mean LES resting pressure was achieved with 0.5 mg, it did not provide any potential therapeutic advantage over 0.25 mg glucagon. Nausea is a common, transient side effect predominantly affecting subjects treated with the 1-mg dose.

Reduced chemoreceptor sensitivity in patients with Barrett's esophagus may be related to age and not to the presence of Barrett's epithelium

BACKGROUND

Patients with Barrett's esophagus have demonstrated reduced chemo- and mechanoreceptor sensitivity to acid infusion and balloon distension, respectively. However, Barrett's esophagus is mainly a disease of the elderly, making age the possible underlying mechanism for altered pain perception in this patient population.

OBJECTIVES

To determine perception thresholds to acid infusion in elderly (>65 yr) versus younger (< or =50 yr) patients with Barrett's esophagus.

METHODS

Twelve elderly and 10 younger patients, matched by length of Barrett's mucosa, were recruited into the study. All patients participated in our Barrett's esophagus surveillance program. The patients were treated with omeprazole 20 to 60 mg/day and were symptom free. Chemosensitivity was determined by a modified acid perfusion test, in which acid perception thresholds were quantified by the lag time to initial typical symptom perception, sensory intensity rating, and an acid perfusion sensory score.

RESULTS

Five of the elderly patients with Barrett's esophagus had a negative test, whereas all younger patients with Barrett's esophagus experienced typical symptom perception during acid infusion. Elderly patients with Barrett's esophagus had significantly longer lag time to initial perception, lower acid perfusion sensory score, and sensory intensity rating in comparison with the younger patients.

CONCLUSIONS

Reduced chemoreceptor sensitivity to acid perfusion that has previously been demonstrated in patients with Barrett's esophagus may be related to age and not to the presence of Barrett's epithelium.