ABSTRACT
We encountered two cases of infection with large female nematodes of the genus Philometra Costa, 1845 in the body cavity of a map puffer Arothron mappa (Lesson) caught off Okinawa, Japan, and a blackspotted puffer Arothron nigropunctatus (Bloch et Schneider) caught off Queensland, Australia, both reared in aquariums in Japan. No morphological difference was observed between the nematodes from A. mappa and A. nigropunctatus. We identified the nematodes as Philometra pellucida (Jägerskiöld, 1893) based on their morphology. The sequences of the nematodes from both hosts were identical to each other (1,643 bp) and formed a clade with other 17 nematodes belonging to the genera Philometra and Philometroides Yamaguti, 1935 with high bootstrap value (bp = 100). It is the first time that the genetic data on P. pellucida are provided. Philometra robusta Moravec, Möller et Heeger, 1992 is synonymised with the former species.
Subject(s)
Dracunculoidea/classification , Dracunculoidea/physiology , Fish Diseases/parasitology , Spirurida Infections/veterinary , Tetraodontiformes , Animals , Animals, Zoo , Dracunculoidea/anatomy & histology , Female , Japan , Queensland , Spirurida Infections/parasitologyABSTRACT
Kudoa septempunctata, a myxosporean parasite infecting the trunk muscles of olive flounder (Paralichthys olivaceus), is reported to cause food poisoning in humans. The molecular mechanisms underlying the toxicity of K. septempunctata spores remain largely unknown. In the present study, we examine the molecular basis of such toxicity using DNA microarray analysis of K. septempunctata-inoculated human colon adenocarcinoma cells (Caco-2). We observed that the transepithelial resistance of the K. septempunctata-inoculated Caco-2 cell monolayers decreased markedly. DNA microarray analysis revealed that the mRNA expression profiles of control and inoculated cells clearly differed. Inflammatory and bacteria-related pathways, such as interleukin-8 (IL-8) production and MAPK/NF-kappa B pathway, were enriched. The concentrations of IL-8 and serotonin (5-HT) were higher in inoculated cells than in controls. K. septempunctata invasion damages the human intestinal epithelium, causing increased production of IL-8 and 5-HT, which likely results in the vomiting associated with K. septempunctata invasion.Abbreviations: AP-1: activator protein 1; DAVID: Database for Annotation, Visualization and Integrated Discovery; ENS: enteric nervous system; FARMS: Factor Analysis for Robust Microarray Summarization; FDR: false discovery rate; GO: Gene Ontology; 5-HT: 5-hydroxytryptamine; IL-8: Interleukin-8; KEGG: Kyoto Encyclopedia of Genes and Genomes; K. septempunctata: Kudoa septempunctata; NF-kappa B: nuclear factor-kappa B; TJ: tight junction; TER: transepithelial electrical resistance.
