Abstract: The present invention provides a method of assisting a determination of whether a subject is susceptible to infection by norovirus or whether a subject is susceptible to post-infection worsening, wherein this method contains a step of measuring the concentration of IgG antibody that is present in a sample originating from within the oral cavity of the subject.

Abstract: One object of the present invention is to provide an inhibitor for renal injuries induced by an iodinated contrast medium. In this invention, cilastatin or a pharmaceutically acceptable salt thereof is used.

Abstract: An object of the present invention is to solve problems in terms of stagnation of research on norovirus by providing a cultured transgenic cell or a transgenic animal in which murine norovirus (MNV) can be grown across the barrier of host specificity in mammalian cells, and providing a screening method that uses the cultured transgenic cell or the transgenic animal. The present inventors have found that MNV infection is determined in a cultured transgenic mammalian cell or a mammal possessing the cultured transgenic mammalian cell as its own cell, the cultured transgenic mammalian cell containing one or more species selected from the entirety or a portion of the murine CD300F gene and/or a CD300 family gene having an extracellular domain nucleotide sequence similar to that of the murine CD300F gene. The present inventors have solved the aforementioned problems by providing, for example, a norovirus-related drug screening method on the basis of this finding.

Abstract: One object of the present invention is to provide an inhibitor for renal injuries induced by an iodinated contrast medium. In this invention, cilastatin or a pharmaceutically acceptable salt thereof is used.

Abstract: An object of the present invention is to solve problems in terms of stagnation of research on norovirus by providing a cultured transgenic cell or a transgenic animal in which murine norovirus (MNV) can be grown across the barrier of host specificity in mammalian cells, and providing a screening method that uses the cultured transgenic cell or the transgenic animal. The present inventors have found that MNV infection is determined in a cultured transgenic mammalian cell or a mammal possessing the cultured transgenic mammalian cell as its own cell, the cultured transgenic mammalian cell containing one or more species selected from the entirety or a portion of the murine CD300F gene and/or a CD300 family gene having an extracellular domain nucleotide sequence similar to that of the murine CD300F gene. The present inventors have solved the aforementioned problems by providing, for example, a norovirus-related drug screening method on the basis of this finding.