Surveillance of Shiga toxin-producing Escherichia coli in beef with effective procedures, independent of serotype.

To detect various serotypes of Shiga toxin-producing Escherichia coli (STEC) in food, methods independent of serotyping are needed. We established procedures to isolate STEC using a rapid and sensitive loop-mediated isothermal amplification (LAMP) assay targeting the Shiga toxin (ST) gene and a method of plating LAMP assay positive dilutions onto media for the selection of E. coli.

[Applicability of GC, GC/MS and liquid chromatography with tandem mass spectrometry to screening for 140 pesticides in agricultural products].

The applicability of GC, GC/MS and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to screening for 140 pesticides in agricultural products was examined. Validation of multi-residue screening methods for the determination of 88 pesticides in 12 crops (asparagus, cauliflower, burdock, carrot, broccoli, spinach, matsutake mushroom, orange, soybean, sesame, millet and tea) was done by GC and GC/MS. Of the 88 pesticides, 63 were obtained with recoveries in the range from 50 to 150% at the 0.

[Screening method for the determination of 199 pesticides in agricultural products by gas chromatography/ion trap mass spectrometry (GC/MS/MS)].

A screening method is described for determining 200 pesticides, except dimethipin, divided into four groups by means of gas chromatography/tandem mass spectrometry (GC/MS/MS) using an ion trap mass spectrometer equipped with automated gain control (AGC). The quantitation limit for 194 pesticides was 0.01 mg/kg on a crop basis, except for allidochlor, dimethoate, hexythiazox, methamidophos and triadimenol.

Preliminary genetic characterization of two lineages of black rats (Rattus rattus sensu lato) in Japan, with evidence for introgression at several localities.

We conducted a pilot survey of genetic diversity among 37 karyotyped individuals of the black rat Rattus rattus (sensu lato) from six localities on the Japanese Islands, using complete gene sequences of mitochondrial cytochrome b (cyt b) and nuclear interphotoreceptor retinoid binding protein (IRBP). Our sampling included two previously documented karyotypic groups: 'Oceanian' with 2n = 38 and 'Asian' with 2n = 42. Cyt b sequences for most individuals clustered according to their karyotypic groups, with an average between-group divergence of 3.