Improved molecular identification of Strongyloides myopotami in nutrias using fecal samples.

Strongyloides myopotami is an intestinal nematode parasite of nutrias. Identification of S. myopotami is conducted based on the morphological characteristics of adult worms or cultured larvae. To widely and effectively understand the infection in nutrias, it would be preferable to develop the molecular identification using a few grams of the feces. Here, we attempted to identify S. myopotami using DNA extracted from eggs obtained from fecal samples. Among previously reported primer pairs targeting the 18S rRNA gene of Strongyloides spp., most could not be successful. We newly designed primers that successfully amplified the partial sequences in S. myopotami, resulting in being sequenced. Our simple protocol can be useful in nationwide surveys for clarifying the risk of human infection.

Isolation and characterization of Escherichia albertii from wild and safeguarded animals in Okayama Prefecture and its prefectural borders, Japan.

Escherichia albertii has recently been recognized as a zoonotic enteropathogen associated with food poisoning. The reservoirs and transmission routes of this bacterium to humans are still unclear. In this study, we performed a survey of E. albertii in fecal specimens of wild and safeguarded animals in Okayama Prefecture and its prefectural borders, Japan to understand its reservoir in the environment. Forty-two E. albertii were isolated from 10 and 31 droppings of 59 crows and 125 starlings, respectively. Fifty-two E. albertii were isolated from 906 mammal droppings, and out of 52 isolates, origin of 33, 6 and 1 isolates were from martens, foxes, and rabbit, respectively, however, origin of 12 isolates remained unknown. Three E. albertii were isolated from two and one feces of 159 dogs and 76 cats, respectively. Pulsed-filed gel electrophoresis analysis grouped 97 E. albertii strains into 66 pulsotypes including 36 and 30 pulsotypes of isolates from mammals and birds, respectively. E. albertii strains isolated in this study were genetically diverse. Although clonal relationship was not observed between mammal and bird isolates, there were intra- and inter-species relationship in mammalian isolates. All E. albertii strains were positive for eae and Eacdt virulence genes. Furthermore, 20 and 7 strains also carried Eccdt-I and stx2f genes, respectively. Taken together, the results indicate that genetically diverse and potentially virulent E. albertii are distributed among various wild and safeguarded animals in Okayama Prefecture, and the animals could also be reservoirs of E. albertii.

Effects of uric acid on nitrosation of N-acetylcysteine by diethylamine NONOate and N-acetyl-N-nitrosotryptophan.

Uric acid of human plasma concentration accelerated nitrosation of N-acetylcysteine by diethylamine NONOate at neutral pH, but diminished that of N-acetyltryptophan. Uric acid also accelerated nitrosation of N-acetylcysteine by N-acetyl-N-nitrosotryptophan, having a nitroso group on the nitrogen atom of the indole ring. N-Acetyl-S-nitrosocysteine was stable even in the presence of uric acid and N-acetyltryptophan at neutral pH, while decomposition of N-acetyl-N-nitrosotryptophan was accelerated by uric acid and N-acetylcysteine. The results indicate that uric acid receives a nitroso group from diethylamine NONOate or N-acetyl-N-nitrosotryptophan, and passes it to the thiol group of N-acetylcysteine resulting in N-acetyl-S-nitrosocysteine. This implies that uric acid may act as an effective transporter of nitric oxide to thiols resulting in accumulation of nitrosothiols in humans.