Description of a new Nipergasilus species (Family: Ergasilidae) from the gills of grey mullet

A new Nipergasilus species is described from the gills of the grey mullet Valamugil cunnesius from several localities in India and Pakistan. The new species is closely related to Nipergasilus bora (Yamaguti, 1939) which is also recorded here on three species of grey mullet. The genus Nipergasilus is redefined in order to accommodate the second species.     

New species and new records of Ergasilus Nordmann (Copepoda: Ergasilidae) from the gills of grey mullet (Mugilidae)

Four new Ergasilus species are described from five host species of grey mullet, family Mugilidae, held in the fish collections of The Natural History Museum, London. Ergasilus extensus n. sp. was found on Myxus petardi (Castelnau) from Australia, E. sittangenesis n. sp. on Sicamugil hamiltoni (Day) from Burma, E. piriformis n. sp. on Sicamugil cascasia (Hamilton Buchanan) from India, and E. ecuadorensis n. sp. on Mugil curema Valenciennes and M. hospes Jordan & Culver from Ecuador. New records of E. cyanopictus Caravalho, E. magnicornis Yin, E. orientalis Yamaguti and E. rostralis Ho, Jayarajian & Radhakrishnan on grey mullet are also given.     

Role of serum Metadherin mRNA expression in the diagnosis and prediction of survival in patients with colorectal cancer

Molecular Biology Reports - Early diagnosis and treatment of colorectal cancer (CRC) are important for improving patients’ survival. Metadherin is an oncogene that plays a pivotal role in...     

A new copepod (Siphonostomatoida: Lernanthropidae) parasitic on a Red Sea immigrant dragonet (Actinopterygii: Callionymidae), with a review of records of parasitic copepods from dragonets

A new species of parasitic copepod of the family Lernanthropidae is described from an immigrant population of the blotchfin dragonet Callionymus filamentosus Valenciennes (family Callionymidae) in the Eastern Mediterranean. Both sexes are described on the basis of material caught in Egyptian waters off the Alexandria coast at Abuqir. The new species shares with Lernanthropus breviculus Kabata, 1979 the possession of a small dorsal plate on the trunk that is so narrow at its origin that it does not overlap the bases of the fourth legs, which are therefore visible in dorsal view. These species differ in the shape of the cephalothorax and in the extent of the dorsal plate, which is shorter in the new species, revealing the caudal rami in dorsal view. Previous records of parasitic copepods utilising callionymids as hosts are reviewed: most belong to the families Pennellidae and Chondracanthidae.     

Direct actions of organophosphate anticholinesterases on nicotinic and muscarinic acetylcholine receptors

Four nerve agents and one therapeutic organophosphate (OP) anticholinesterase (anti-ChE) bind to acetylcholine (ACh) receptors, inhibit or modulate binding of radioactive ligands to these receptors, and modify events regulated by them. The affinity of nicotinic (n) ACh receptors of Torpedo electric organs and most muscarinic (m) ACh receptors of rat brain and N1E-115 neuroblastoma cultures for the OP compounds was usually two to three orders of magnitude lower than concentrations required to inhibit 50% (IC-50) of ACh-esterase activity. However, a small population of m-ACh receptors had an affinity as high as that of ACh-esterase for the OP compound. This population is identified by its high-affinity [³H]-cis-methyldioxolane ([³H]-CD) binding. Although sarin, soman, and tabun had no effect, (O-ethyl S[2-(diisopropylamino)ethyl)] methyl phosphonothionate (VX) and echothiophate inhibited competitivel the binding of receptors. However, VX was more potent than echothiophate in inhibiting this binding and 50-fold more potent in inhibiting carbamylcholine (carb)-stimulated [³H]-cGMP synthesis in N1E-115 neuroblastoma cells—both acting as m receptor antagonist. All five OPs inhibited [³H]-CD binding, with IC-50s of 3, 10, 40, 100, and 800 nM for VX, soman, sarin, echothiophate, and tabun, respectively. The OP anticholinesterases also bound to allosteric sites on the n-ACh receptor (identified by inhibition of [³H]-phencyclidine binding), but some bound as well to the receptor's recognition site (identified by inhibition of [¹²⁵I]-α-bungarotoxin binding). Soman and echothiophate in micromolar concentrations acted as partial agonists of the n-ACh receptor and induced receptor desensitization. On the other hand, VX acted as an open channel blocker of the activated receptor and also enhanced receptor desensitization. It is suggested that the toxicity of OP anticholinesterases may include their action on n-ACh as well as m-ACh receptors if their concentrations in circulation rise above micromolar levels. At nanomolar concentrations their toxicity is due mainly to their inhibition of ACh-esterase. However, at these low concentrations, many OP anticholinesterases (eg, VX and soman) may affect a small population of m-ACh receptors, which have a high affinity for CD. Such effects on m-ACh receptors may play an important role in the toxicity of certain OP compounds.     

Biogeography and phylogeny of Dermoergasilus Ho & Do, 1982 (Copepoda: Ergasilidae), with descriptions of three new species

Three new species of Dermoergasilus are described from six species of grey mullet hosts. Dermoergasilus longiabdominalis n. sp. was found on Valamugil engeli (Bleeker) from the Philippines and Madagascar and on V. cunnesius (Valenciennes) from the Philippines and Mangalore, India. D. semiamplectens n. sp. occurred on Sicamugil hamiltoni (Day) from the Sittang River, Burma, on Liza subviridis (Valenciennes) and L. parsia (Hamilton Buchanan) from Calcutta, India, and on V. cunnesius (Valenciennes) from China. D. curtus n. sp. parasitised Rhinomugil squamipinnis (Swainson) from Alahabad, India. A key to the ten currently accepted species of Dermoergasilus is given. The biogeographical distribution of Dermoergasilus species is analysed and levels of host-specificity are surveyed within the genus. The phylogenetic relationships between the species of Dermoergasilus are also analysed.