Amino acid residues 253 and 591 of the PB2 protein of avian influenza virus A H9N2 contribute to mammalian pathogenesis.

We investigated the tropism, host responses, and virulence of two variants of A/Quail/Hong Kong/G1/1997 (H9N2) (H9N2/G1) with D253N and Q591K in the PB2 protein in primary human macrophages and bronchial epithelium in vitro and in mice in vivo. Virus with PB2 D253N and Q591K had greater polymerase activity in minireplicon assays, induced more tumor necrosis factor alpha (TNF-α) in human macrophages, replicated better in differentiated normal human bronchial epithelial (NHBE) cells, and was more pathogenic for mice. Taken together, our studies help define the viral genetic determinants that contribute to pathogenicity of H9N2 viruses.

Mutations on the Switch III region and the alpha3 helix of Galpha16 differentially affect receptor coupling and regulation of downstream effectors.

Background: Galpha16 can activate phospholipase Cbeta (PLCbeta) directly like Galphaq. It also couples to tetratricopeptide repeat 1 (TPR1) which is linked to Ras activation. It is unknown whether PLCbeta and TPR1 interact with the same regions on Galpha16.

Nodal detection in malignant melanoma of the vagina using laparoscopic ultrasonography.

Background: Primary malignant melanoma of the vagina is a rare variant of melanoma. It has worse prognosis compared to nongenital melanomas or other vaginal malignant neoplasms.

Case: A 40-year-old Chinese was diagnosed vaginal melanoma.