NP(Δc375) is a truncated version of the nucleocapsid protein of Newcastle disease virus (NDV) which self-assembles into a long helical structure. A packed bed anion exchange chromatography (PB-AEC), SepFastTM Supor Q pre-packed column, was used to purify NP(Δc375) from clarified feedstock. This PB-AEC column adsorbed 76.2% of NP(Δc375) from the clarified feedstock. About 67.5% of the adsorbed NP(Δc375) was successfully eluted from the column by applying 50 mM Tris-HCl elution buffer supplemented with 0.5 M NaCl at pH 7. Thus, a recovery yield of 51.4% with a purity of 76.7% which corresponds to a purification factor of 6.5 was achieved in this PB-AEC operation. Electron microscopic analysis revealed that the helical structure of the NP(Δc375) purified by SepFast(TM) Supor Q pre-packed column was as long as 490 nm and 22-24 nm in diameter. The antigenicity of the purified NP(Δc375) was confirmed by enzyme-linked immunosorbent assay.
OBJECTIVE:
To develop and validate a Mandarin version of the Leeds Dyspepsia Questionnaire (M-LDQ) in Asian patients with dyspepsia.
METHODS:
The M-LDQ was developed according to standardized methods. The validity, internal consistency, test-retest reliability and responsiveness of the instrument were evaluated in both primary and secondary care patients.
RESULTS:
A total of 184 patients (mean age 54.0 ± 15.8 years, of whom 59% were women and 72.3% of whom had at least secondary level education) were recruited between August 2012 and March 2013, from both primary (n = 100) and secondary care clinics (n = 84). Both the internal consistency of all components of the M-LDQ (Cronbach's α 0.79) and test-retest reliability (Spearman's correlation coefficient 0.78) were good. The M-LDQ was valid in diagnosing dyspepsia in primary care (area under the receiver operating characteristics curve 0.84) and was able to discriminate between secondary and primary care patients (median cumulative LDQ score 13.0 vs 3.0, P < 0.0001). Among eight patients with organic dyspepsia, the median M-LDQ score reduced significantly from 21.0 (pretreatment) to 9.5 (4 weeks post-treatment) (P < 0.0001).
CONCLUSION:
The M-LDQ is a valid and responsive instrument for assessing ethnic Chinese adults with dyspepsia.