[Determination method of clomeprop and clomeprop acid in livestock and seafood products by LC-MS/MS].

A method using liquid chromatography with tandem mass spectrometry has been developed for the determination of clomeprop and its metabolite clomeprop acid in livestock and seafood products. Clomeprop and clomeprop acid were extracted with acetone-n-hexane mixture under acidic conditions, and were defatted by liquid-liquid separation using acetonitrile and n-hexane, followed cleanup with SAX and PSA cartridges. The average recoveries from 10 kinds of food (bovine muscle, bovine fat, bovine liver, milk, yellowtail, salmon, eel, fresh water clam, egg and honey) spiked at the level of the MRLs or at uniform limits (0.

Glucose-induced translocation of coronin 3 regulates the retrograde transport of the secretory membrane in the pancreatic beta-cells.

GTP-Rab27a is known to regulate insulin exocytosis. We have recently reported that coronin 3, which paradoxically binds GDP-Rab27a, participates in endocytosis of the insulin secretory membrane. Here, we demonstrate that glucose stimulation caused redistribution of coronin 3 in the vicinity of the plasma membrane, which was mimicked by overexpression of the GDP-Rab27a mutant or the Rab27a GAP.

Nontypeable Haemophilus influenzae isolated from intractable acute otitis media internalized into cultured human epithelial cells.

Objectives: The aim of this study is to examine the internalization of nontypeable Haemophilus influenzae (NTHi) into human epithelial cells.

Methods: Bactericidal assay was applied to examine the effects of antibiotics against cell-adherent NTHi using HEp-2 cells. A trans-well chamber assay was applied to examine the internalization and penetration of NTHi using Detroit562 cells.

[Determination of spiramycin and tilmicosin in meat and fish by LC/MS].

A simple and reliable method using liquid chromatography-electrospray ionization-mass spectrometry (LC/ESI-MS) has been developed for the determination of the macrolide antibiotics spiramycin and tilmicosin in meat and fish. The drugs were extracted from meat and fish with 0.2% metaphosphoric acid-methanol (6:4), and the extracts were cleaned up on an Oasis HLB cartridge (60 mg).