Deroceras panormitanum and congeners from Malta and Sicily, with a redescription of the widespread pest slug as Deroceras invadens n. sp.

The name Deroceras panormitanum is generally applied to a terrestrial slug that has spread worldwide and can be a pest; earlier this tramp species had been called Deroceras caruanae. Neither name is appropriate. The taxonomic descriptions apply to a species from Sicily and Malta. This true D. panormitanum and the tramp species are distinct in morphology and mating behaviour. For instance, the penial caecum of D. panormitanum is more pointed, everting faster at copulation. The size of the penial lobe varies considerably in preserved specimens but is always prominent at copulation. D. panormitanum is distinct from the Maltese endemic Deroceras golcheri, but a phylogeny based on mtDNA COI sequences implies that they are more closely related than is the tramp species. D. golcheri has a still closer counterpart on Sicily, but we leave the taxonomy of this species X unresolved. In interspecific crosses, D. panormitanum may transfer sperm to the partner's sarcobelum whereas the partner fails to evert its penis (D. golcheri) or to transfer sperm (the tramp species). Names previously applied to the tramp species originally referred to D. panormitanum or are otherwise invalid, so it is here formally redescribed as D. invadens. Deroceras giustianum Wiktor, 1998 is synonymised with D. panormitanum

Determination of the effect of collars containing 10% w/w imidacloprid and 4.5% w/w flumethrin (Seresto®) on the incidence of Leishmania and other canine vector-borne pathogen infections in Greece

Background: The objective of this field study was to assess the effect of treating a considerable portion of a dog population naturally exposed to canine vector-borne pathogens (CVBPs) in endemic areas with a 10% w/w imidacloprid/4.5% w/w flumethrin collar (Seresto®) on the transmission of CVBPs and the resulting incidence of infection. Methods: A total of 479 dogs from two sites were enrolled in the study. Collars were placed on all dogs continuously for 21 months, with replacement of the collar every 7 months. All dogs were examined, including body weight and blood/conjunctival swab collections, every 7 months. Serum samples were analysed for the presence of antibodies against Leishmania infantum, Ehrlichia canis and Anaplasma phagocytophilum. PCR assays were also performed on blood samples and conjunctival swab collected from the dogs for the presence of L. infantum, and on blood samples only for the presence of Ehrlichia spp. and Anaplasma spp. Sand flies were collected, identified to species level and molecularly tested for L. infantum throughout two vector activity seasons. Results: The results showed that the Seresto collar was safe with continuous use. At study inclusion, 419, 370 and 453 dogs tested negative for L. infantum, Ehrlichia spp. and Anaplasma spp., respectively (353 dogs tested negative for any pathogen). Overall, 90.2% of the dogs were protected from L. infantum infection on both sites combined. The entomological survey confirmed the presence of competent vectors of L. infantum at all monitored locations, namely the sand flies Phlebotomus neglectus and Phlebotomus tobbi, both of which are regarded as the most important competent vectors in the Mediterranean basin. All captured sand flies tested negative for L. infantum. Protection against ticks and fleas was high, with only two dogs showing a low number of ticks and seven dogs having low numbers of fleas at single evaluation time points. Across the entire study population, a number of dogs became infected with tick-transmitted pathogens, but prevention of transmission was 93% for E. canis and 87.2% for Anaplasma spp. when all cases from both sites were combined. Conclusions: The Seresto® (10% w/w imidacloprid/4.5% w/w flumethrin) collar significantly reduced the risk of CVBP transmission when compared to previously observed incidences of CVBP infections in two highly endemic areas under field conditions

Evidence for a less high acceptor substrate specificity of gastric histamine methyltransferase: methylation of imidazole compounds

The transmethylation catalysed by HMT (EC 2.1.1.8)* has been considered as absolutely specific for histamine as acceptor substrate. In this investigation Nα-MH, Nα,NαDMH, spinaceamine and synthetically prepared 4-[(2-amino-ethylmercapto)-methyl]-imidazole could be identified as further methyl-group accepting substrates (optimum substrate concentration ~ 1 mM), but the yield of extractable 14C-labelled methylation products was never greater than 21 per cent of that of histamine. The 3 per cent methylation of Nα,Nα-DMH was considerably smaller than that of 33 per cent reported in the literature. This discrepancy was resolved and found to be ascribable to an inappropriate product extraction procedure used in the former experiments. When Nα-MH and Nα,Nα-DMH were the substrates, the corresponding products were isolated by t.1.c. in four different solvent systems and identified to be Nτ,Nα-DMH and Nτ,Nα,Nα-TMH. Thus HMT catalysed in all cases a uniform methyl of the Nα-nitrogen atom of the imidazole nucleus. The investigation of a series of various substituted imidazole compounds revealed that a methylation of the ring system had to be considered, if it was not substituted in the Nτ-, 2- or Nπ-position and if it carried a 4-substituent with a strong basic aminogroup, whereas substitution in the ring 5-position seemed to be of minor importance. Furthermore H1-receptor antagonists, H2-receptor antagonists, the non-imidazole H2-receptor agonist dimaprit, as well as the enzyme inhibitors aminoguanidine, tranylcypromine, pargyline and nicolinamide, were not methylated under the catalysis of HMT. The evidence for a less high substrate specificity of HMT may influence the relevance of histamine determinations using this enzyme: caution seems necessary

Deroceras panormitanum and congeners from Malta and Sicily, with a redescription of the widespread pest slug as Deroceras invadens n. sp.

The name Deroceras panormitanum is generally applied to a terrestrial slug that has spread worldwide and can be a pest; earlier this tramp species had been called Deroceras caruanae. Neither name is appropriate. The taxonomic descriptions apply to a species from Sicily and Malta. This true D. panormitanum and the tramp species are distinct in morphology and mating behaviour. For instance, the penial caecum of D. panormitanum is more pointed, everting faster at copulation. The size of the penial lobe varies considerably In preserved specimens but is always prominent at copulation. D. panormitanum is distinct from the Maltese endemic Deroceras golcheri, but a phylogeny based on mtDNA COI sequences implies that they are more closely related than is the tramp species. D. golcheri has a still closer counterpart on Sicily, but we leave the taxonomy of this “species X” unresolved. In interspecific crosses, D. panormitanum may transfer sperm to the partner’s sarcobelum whereas the partner fails to evert its penis (D. golcheri) or to transfer sperm (the tramp species). Names previously applied to the tramp species originally referred to D. panormitanum or are otherwise invalid, so it is here formally redescribed as D. invadens. Deroceras giustianum Wiktor, 1998 is synonymised with D. panormitanum

Histamine H3-receptor antagonist inhibit gastroprotection by (R)-alfa-methylhistamine in the rat

1 (R)-alpha-methylhistamine, a selective agonist of hist amine H-3 receptors, is capable of protecting the gastric mucosa against differently acting damaging agents. The objective of the present study was to determine whether H-3 receptors mediate its protective action in the rat. 2 Gastric mucosal lesions were induced intragastrically (i.g.) by 0.6 N HCl, 1 mi rat(-1). (R)-alpha-methylhistamine, 100 mg kg(-1) i.g., substantially reduced the severity of macroscopically and histologically assessed damage caused by concentrated acid. Prior treatment with highly selective H-3- receptor antagonists, ciproxifan (0.3, 1 and 3 mg kg(-1) i.g.) and clobenpropit (3, 10 and 30 mg kg(-1) i.g.), dose-dependently inhibited the protection exerted by (R)-alpha-methylhistamine up to a complete reversal. When given alone at high doses, both antagonists tended to worsen the HCl-induced histologic damage. 3 During basal conditions, (R)-alpha-methylhistamine, 100 mg kg(-1) i.g., caused a significant increase in titratable acidity of the gastric juice. Prior treatment with ciproxifan (3 mg kg(-1) i.g.) and clobenpropit (30 mg kg(-1) i.g.) did not alter the secretory response to (R)-alpha-methylhistamine. Clobenpropit alone, but not ciproxifan, increased the volume of gastric juice, and both compounds alone had no effect on titratable acid. 4 Present findings support evidence that H-3 receptors an actively involved in the maintenance of gastric mucosal integrity, with no apparent role in the regulation of basal gastric acid secretion