Objective To analyze the MR manifestations of the focal nodular hyperplasia (FNH)in liver and observe the MRI changes after 30-36 months.Methods 12 (14 lesions)of the 13 patients (1 5 lesions)were firstly diagnosed as FNH by MRI with plain scan and dynamic Gd-DTPA enhancement,and then were confirmed by the follow-up survey with similar MRI after 30 - 36 months.The last one patient was also scanned with Gd-EOB-DTPA enhancement but with similar plain scans.The size,signal,en-hancement patterns of the lesions were analyzed and compared with those in the follow-up survey.Results Typical MR manifesta-tions were found in 93.33%(14/1 5)of the lesions with hypo-or iso-intensity on T1 WI,hyper-or iso-intensity on T2 WI,marked en-hancement in arterial phase and attenuation but still equal to or higher than normal liver parenchyma in portal and delayed phases af-ter Gd-DTPA administration.In addition,the central scar showed hypointensity on T1 WI,hyperintensity on T2 WI,and enhance-ment in delayed phase.The enhanced small vessels inside lesions and the pesudocapsule enhancement could be seen in delayed phase. The only one lesion with Gd-EOB-DTPA enhancement showed marked enhancement in arterial and portal phases,and slight hyperin-tensity in hepatocellular phase with hypo-intense central scar in any phases.As for the only one lesion with atypical manifestation,it showed isointensity on T1 WI,slightly hyperintensity on T2 WI,nonenhancement in arterial phase,slightly enhancement in portal phase,and small vascular enhancement inside the lesion in delayed phase.After the follow-up survey of 30-36 months 92.86%(13/14)lesions did not change,however one lesion (10mm)disappeared.Conclusion Typical FNH shows similar MRI characteristics, iso-intense or slightly hypo-intense signal on T1 WI,iso-intense or slightly hyper-intense signal on T2 WI,marked enhancement in ar-terial phase,the central scar enhancement and the inside small vascular enhancement of lesions in delayed phase.It is valuable in dif-ferential diagnosis.

Objective To study the interactions between the highly pathogenic avian influenza H5N1 nucleoprotein (H5N1 NP) and NF-κB-inducing kinase (NIK),and to reveal the effect of H5N1 NP on NIK-induced NF-κB transcriptional activity.Methods The gene encoding NIK protein was amplified by RT-PCR from total RNA of HeLa cell line.Eukaryotic expression plasmid pCMV-Myc-NIK and prokaryotic expression plasmid pGEX-4T-1-NP (GST-NP) were constructed by cloning from HeLa cell cDNA and pcDNA3-Flag-NP vector,respectively.Co-immunoprecipitation (co-IP) and GST pull-down were used to test the interactions between H5N1 NP and NIK.Dual-luciferase reporter gene analysis system was used to test the effect of H5N1 NP on NIK-induced NF-κB transcriptional activity.Results Co-IP and GST pull-down showed that pCMV-Myc-NIK and pGEX-4T-1-NP (GST-NP) could express Myc tagged NIK protein and GST tagged NP protein in HEK293T cells and E.coli,respectively,and that H5N1 NP was associated with NIK in vivo and in vitro.Dual-luciferase reporter gene analysis suggested that H5N1 could inhibit NIK-induced NF-κB transcriptional activity.Conclusion H5N1 NP interacts with NIK and inhibits NIK-induced NF-κB transcriptional activity.This finding can facilitate further study of H5N1.

Objective To investigate the genetic characteristics and recombination of human-infected sapoviruses(SaVs)worldwide using bioinformatics.Methods The complete genome sequences of SaVs were downloaded from the National Center for Biotechnology Information(NCBI)while high-quality complete genomes were retained for analysis.Molecular phylogenetic trees of SaVs were constructed to analyze their genetic characteristics,followed by recombination analysis of human-infected SaV strains genetype Ⅰ,Ⅱ,Ⅳ,and V(G Ⅰ,G Ⅱ,GⅣ,and GⅤ)with recombination analysis software.Results SaVs exhibited substantial genetic diversity worldwide and infected a wide range of hosts.Human-associated SaVs included G Ⅰ,G Ⅱ,GⅣ,and GⅤ,with GⅤ shared between human and swine hosts.Genetype recombination analysis of SaVs revealed a high frequency of recombination in SaV G Ⅱ strains that involved diverse hosts in the field of SaV G V strains.Recombination breakpoints of the virus were concentrated in the major viral proteins 1(VP1)and minor viral proteins 2(VP2).Conclusion Based on systematic analysis of the genetic characteristics of human-infected SaVs,the genotype distribution and prevalence of SaVs are investigated,the recombination patterns of SaV revealed,and its genetic dynamics highlighted.These findings can offer insights into epidemiological trends of viruses and help devise effective prevention and control strategies.