The whole-blood Epstein-Barr virus DNA can serve as a valuable molecular marker for diagnosis and prognosis prediction of nasopharyngeal carcinoma.

The clinical significance and prognostic role of whole-blood EBV-DNA in EBV-associated nasopharyngeal carcinoma (NPC) have not been thoroughly investigated. This study aims to explore the diagnostic and prognostic value of EBV-DNA for NPC in a non-endemic region of China. We enrolled patients with chronic active EBV infection (CAEBV), nasopharyngitis (NA), extranodal NK/T-cell lymphoma, nasal type (ENKTCL-NT), and NPC. Demographic and clinical data were collected and the diagnostic and prognostic values of EBV-DNA were analyzed. Immunohistochemistry was performed to detect EBV-encoded small ribonucleic acids (EBER), as well as the expression of p53, Ki-67, and epidermal growth factor receptor (EGFR). The levels of pretreatment Epstein-Barr virus DNA (preEBV-DNA) in new NPC cases were found to differ from those in other diseases and exhibited varying age distributions. The threshold value of preEBV-DNA for distinguishing NPC from CAEBV and NA was determined. We confirmed that epistaxis, diabetes mellitus, T3N2 or T4N0-2 stage, and IgM positivity were associated with higher levels of preEBV-DNA, and identified risk factors associated with the prognosis of locoregionally advanced NPC (La-NPC). Patients with intermittently or persistently positive EBV-DNA (IPCP), higher preEBV-DNA levels, and positive Epstein-Barr virus-encoded small RNA (EBER) status (EBERpos) had worse survival. New cases of NPC with elevated levels of EBV in the whole-blood and positive EBER status were shown to have a poor prognosis upon progression to La-NPC. EBV-DNA was found to be an indicator for predicting prognosis in La-NPC and could also be used to distinguish new NPC cases.

rpoB gene mutations in rifampin-resistant Mycobacterium tuberculosis isolates from rural areas of Zhejiang, China.

OBJECTIVE: The aim was to analyze genetic mutations in the rpoB gene of rifampin-resistant Mycobacterium tuberculosis isolates (RIFR-MTB) from Zhejiang, China. METHODS: We prospectively analyzed RIFR-associated mutations in 13 rural areas of Zhejiang. Isolates were subjected to species identification, phenotype drug susceptibility testing (DST), DNA extraction, and rpoB gene sequencing. RESULTS: A total of 103 RIFR isolates were identified by DST (22 RIFR only, 14 poly-drug resistant, 49 multidrug resistant, 13 pre-extensively drug resistant [pre-XDR], and 5 extensively drug resistant [XDR]) from 2152 culture-positive sputum specimens. Gene sequencing of rpoB showed that the most frequent mutation was S450L (37.86%, 39/103); mutations P280L, E521K, and D595Y were outside the rifampicin resistance-determining region (RRDR) but may be associated with RIFR. Mutations associated with poly-drug resistant, pre-XDR, and XDR TB were mainly located at codon 445 or 450 in the RRDR. CONCLUSIONS: The frequency of rpoB RRDR mutation in Zhejiang is high. Further studies are needed to clarify the relationships between RIFR and the TTC insertion at codon 433 in the RRDR and the P280L and D595Y mutations outside the RRDR.

Comparative Genomic Analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites.

In the present study, the complete genomes of four common (4/EV71/Wenzhou/CHN/2014, 15/ EV71/Wenzhou/CHN/2014, 116/EV71/Wenzhou/ CHN/2014, and 120/EV71/Wenzhou/CHN/2014) and two virulent (11/EV71/Wenzhou/CHN/2014 and 109/EV71/Wenzhou/CHN/2014) enterovirus 71 (EV71) isolates were sequenced and described. They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster). Nucleotide sequence alignment revealed six nucleotide variations (GP151→TP151, GP199→AP199, GP261→TP261, AP328→CP328, GP422→AP422, and GP437→TP437) in the two virulent isolates within the 5'UTR of the IRES element. RNA secondary structure predictions of IRES and FCE indicated that the common isolates shared similar structures, which were different from those of the virulent isolates. Moreover, the GP114→CP114 and GP151→TP151 mutations in the virulent isolates contributed to the formation of the unique RNA secondary structures in SL II. Furthermore, nucleotide/amino acid sequence alignments of 82 EV71 isolates indicated that six sites (TP488 and CP577 in the 5'UTR; AsnP57 in 2A; IleP56 in 3C; CP10 and AP47 in the 3'UTR) are potentially associated with the neurovirulence of EV71. Finally, the 3D structures of 2A were analogous, whereas the structures of VP1 and 3C were variable.