ABSTRACT
Objective To investigate the molecular characteristics of H5 subtype avian influenza viruses (AIV) in Weining, Guizhou Province. Methods Nine representative strains were randomly select-ed from H5 subtype AIV that were identified by real-time PCR in Weining, Guizhou Province from 2015 to 2017. Nucleic acid was extracted from each sample and hemagglutinin (HA) genes were amplified and then sequenced. Homology, genetic evolution and the sites related to pathogenicity, receptor binding regions as well as potential glycosylation of H5 AIV were analyzed by bioinformation software. Results Homology analysis revealed that there was 96. 1%-99. 9% and 95. 7%-100% similarity among the nine strains in nu-cleotide and amino acid of HA gene, respectively. These strains belonged to two branches, H5-1 and H5-2. The cleavage site motifs were PLREKRRKR↓GLF for five strains in H5-1 branch and PQRERRRKR↓GLF for four strains in H5-2 branch, which made them high pathogenic. QSG and QRG at the key receptor bind-ing sites were found in H5-1 and H5-2 branch strains, respectively. They were responsible for receptor bind-ing specificity of AIV. Mutations of 138Q, 139G and 53K were all detected in the nine strains. 129K, 189T, 140K and 282V mutations were discovered in the five strains of H5-1 branch, while 189N, 140M and 282I mutations were found in the four strains of H5-2 branch. Results of the glycosylation motif analysis showed that six sites were conservative, but there was an addition of 124NHT site in two strains of H5-2 branch isolated in 2017. Conclusion Two high pathogenic H5 subtypes of AIV could be epidemic in Wein-ing, Guizhou Province during 2015 to 2017. Although H5 subtype AIV did not possess specific receptor binding regions like human influenza viruses, they were in continuous variation with an increase in glycosyla-tion motifs, which might enhance their virulence and pathogenicity to human beings. Hence, surveillance and study on the molecular properties of H5 subtype AIV should be strengthened.
ABSTRACT
Objective Medication for pituitary adenomas is mainly targeted on the prolactin-secreting and growth-hormone types and shows poor therapeutic effects on other adenomas .Therefore, new drugs urgently need to be developed for this purpose .This study was to investigate the effects of glivec and everolimus on mouse pituitary AtT-20 cells and their molecular mechanisms in vitro. Methods Mouse pituitary AtT-20 cells were incubated with glivec or everolimus or combination of both and their inhibitory effect on the proliferation of the cells was measured by CCK-8 assay.The mRNA levels of AKT and ERK were determined by q-PCR and the ex-pressions of the phosphorylated AKT (p-AKT) and ERK (p-ERK) were detected by Western blot. Results Used alone, both glivec and everolimus inhibited the proliferation of the AtT-20 cells in a time-and dose-dependent manner , but their combination produced a mutually antagonistic effect, with combination index values of 1.13 ±0.06, 1.12 ±0.03, and 1.07 ±0.03 respectively.The two a-gents , either used alone or in combination , induced no significantly inhibitory effects on the mRNA and protein expressions of AKT and ERK ( P >0.05 ).Both glivec and everolimus up-regulated the expressions of p-AKT and p-ERK, and their combination manifested an even stronger effect (P>0.05). Conclusion Both glivec and everolimus inhibit the proliferation of AtT-20 cells when administered alone, but their combination produces an antagonistic effect .Their action mechanism might be that when targeting some signaling path-ways to inhibit cell proliferation , glivec, as well as everolimus , in-duces a feedback activation of AKT and ERK .