BACKGROUNDTo clarify the features of gene variation among epidemic strains of human rotavirus NSP4 in China.

METHODSSP4 genes from 27 epidemic strains of human rotavirus isolated in different area of China in recent years were amplified with RT-PCR, the resulted cDNAs were cloned and sequenced. The sequences of full length cDNAs were compared with 10 rotavirus NSP4 sequences available in the GenBank using the Clustal x 1.8 TreeView32 and DNA Star softwares. The G serotype of VP7 was analysed by PCR.

RESULTSThe homology of the amino acid among the 27 rotavirus strains isolated in China was 81.7%-99.4%. Based on the variation of amino acid sequence, the virus strains can be divided into two groups, represented by Wa and KUN with the homology of 92.0%-99.4% and 92.0%-98.9% within each group, respectively. The diversity between the two groups were 16.6%-21.0%. The Wa group could further be separated into three subgroups, according to the diversity between those strains and the characterization in the highly variable domain. The association between VP7 serotype and NSP4 genotype was not strong.

CONCLUSIONSThe NSP4 gene of human rotavirus epidemic strains in China can be divided into Wa and KUN two groups, Wa group is the main group and contains three subgroups possessing characteristic amino acid sites. Samples isolated in the same year but not in the same area shared higher homology.

Antigens, Viral ; Capsid Proteins ; genetics ; DNA, Complementary ; analysis ; DNA, Viral ; analysis ; Diarrhea ; virology ; Genetic Variation ; Genotype ; Glycoproteins ; genetics ; Humans ; Phylogeny ; Reverse Transcriptase Polymerase Chain Reaction ; Rotavirus ; genetics ; isolation & purification ; Sequence Analysis, DNA ; Toxins, Biological ; Viral Nonstructural Proteins ; genetics

BACKGROUNDNasopharyngeal carcinoma (NPC) patients have a 19%-56% locoregional recurrence rate after primary therapy. For those recurrent NPC (rNPC) patients, re-irradiation may cause some complications. In recent years, endoscopic endonasal nasopharyngectomy (EEN) has become a surgical option for rNPC patients. Here we introduce the concept of en bloc excision (EBE) technique for EEN, including the surgical technique and clinical outcomes.

METHODSA retrospective study was conducted covering September 2009 to May 2013, involving the collection of locoregional rNPC cases from two institutions (Kuang-Tien General Hospital (KTGH) in Taiwan and National University Health System (NUHS) in Singapore). These patients failed prior therapy and then underwent EEN. We reported the 2-year overall survival rate, the 2-year disease-free survival rate, and related complications.

RESULTSNine patients (five from KTGH and four from NUHS) completed this study, with five, two, and two patients of recurrence tumors (rT1), rT2, and rT3, respectively. The mean age was 46.4 years (range 32-63); the mean follow-up period was 24.9 months (range 10-45). The 2-year survival rate and the 2-year disease-free rate were 100% and 80%, respectively, in five patients. No significant complications or cases of mortality occurred.

CONCLUSIONSThe EBE concept of EEN is suitable for early rT1 and has relatively encouraging short-term outcomes. In selected rT2, careful EBE can be performed by expanding the surgical field. A clear view of the internal carotid artery-related anatomy is indispensable. In the future, more series may be needed to determine the role of EEN in rNPC patients.

Adult ; Carcinoma ; Endoscopy ; methods ; Female ; Humans ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; surgery ; Retrospective Studies ; Treatment Outcome