Genetic polymorphism of circumsporozoite protein of Plasmodium falciparum among Chinese migrant workers returning from Africa to Henan Province.

BACKGROUND: Plasmodium falciparum malaria is recognized as a major global public health problem. The malaria vaccine was important because the case fatality rate of falciparum malaria was high. Plasmodium falciparum circumsporozoite protein (PfCSP) is one of the potential vaccine candidates, but the genetic polymorphism of PfCSP raises concerns regarding the efficacy of the vaccine. This study aimed to investigate the genetic polymorphism of PfCSP and provide data for the improvement of PfCSP-based vaccine (RTS,S malaria vaccine). METHODS: Blood samples were collected from 287 Chinese migrant workers who were infected with P. falciparum and returning from Africa to Henan Province during 2016-2018. The Pfcsp genes were analysed to estimate the genetic diversity of this parasite. RESULTS: The results showed that there were two mutations at the N-terminus of imported Pfcsp in Henan Province, including insertion amino acids (58.71%, 118/201) and A → G (38.81%, 78/201). The number of repeats of tetrapeptide motifs (NANP/NVDP/NPNP/NVDA) in the central repeat region ranged mainly from 39 to 42 (97.51%, 196/201). A total of 14 nonsynonymous amino acid changes were found at the C-terminus. The average nucleotide difference (K) of imported Pfcsp in Henan Province was 5.719, and the haplotype diversity (Hd) was 0.964 ± 0.004. The estimated value of dN-dS was 0.047, indicating that the region may be affected by positive natural selection. The minimum number of recombination events (Rm) of imported Pfcsp in Henan Province was close to that in Africa. The analysis of genetic differentiation showed that there may be moderate differentiation between East Africa and North Africa (Fst = 0.06484), and the levels of differentiation in the other regions were very small (Fst < 0.05). CONCLUSIONS: The N-terminus of Pfcsp was relatively conserved, and the central repeat region and the Th2R and Th3R regions of the C-terminus were highly polymorphic. The gene polymorphism pattern among Chinese migrant workers returning from Africa to Henan Province was consistent with that in Africa. The geographical pattern of population differentiation and the evidence of natural selection and gene recombination suggested that the effect of polymorphism on the efficacy of PfCSP-based vaccines should be considered.

[Identification and Comparison of Constituents of Different Processed Products of Ligubtrum lucidum Fruit by HPLC Fingerprint].

OBJECTIVE: To identify and compare the constituents in different processed products of Ligubtrum lucidum fruit by HPLC fingerprint, in order to study the changes of chemical constituents before and after processing. METHODS: HPLC analysis was carried outwith the mobile phase of acetonitrile and 0.1% formic acid in a gradient elution mode. The number of HPLC fingerprint chromatographic peaks and peak area changes in two processed products and the crude product under 240 nm and 280 nm were compared. Then the obtained fingerprint chromatographic peaks were confirmed according to the the standard references. RESULTS: 40 chromatographic peaks were detected from Ligustrum lucidum fruit, of which 18 chromatographic peaks were confirmed, including eleven iridoids, five phenethyl alcohols, one flavonoid and one aldehyde. 38 chromatographic peaks were detected from both steaming with wine product and the steamed product, of which 15 chromatographic peaks were confirmed, including seven iridoids, five phenethyl alcohols, one flavonoid, one aldehyde and one organic acid. There was a significant difference of fingerprint among crude Ligustrum lucidum fruit and its two processed products, but little difference between steaming with wine product and the steamed product. CONCLUSION: HPLC fingerprint of the steaming with wine product and the steamed product of Ligustrum lucidum fruit are similar while the changes on chemical composition and the content in steaming with wine product and steamed product of Ligustrum lucidum fruit are remarkable.

Comprehensive chemical profiling of monascus-fermented rice product and screening of lipid-lowering compounds other than monacolins.

ETHNOPHARMACOLOGICAL RELEVANCE: Monascus-fermented rice product (MFRP) has been regarded as a dietary supplement and traditional medicine with circulation-promoting effects in China and other countries for centuries. AIM OF THE STUDY: This study was carried out to profile the chemical components in MFRP, and provide available information for elucidating the potential lipid-lowering compounds other than monacolins. MATERIALS AND METHODS: High-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-QTOF MS) and gas chromatography coupled with mass spectrometry (GC-MS) methods were applied to comprehensive analysis of chemical components in MFRP. Potential small molecules were identified by comparing with reference standards, or tentatively characterized by comparing their retention time and high-resolution mass spectral data with previous literature. The lipid-lowering properties of ten major non-monacolin compounds were evaluated in cholesterol-fed zebrafish larvae. And one with optimum lipid-lowering activity was subsequently evaluated in high fat diet-fed C57BL/6 J mice, with the dyslipidemia and ectopic lipid deposition being investigated. RESULTS: A total of 99 compounds were characterized in MFRP, including 38 monacolins, 5 decalins, 6 isoflavones, 13 pigments, 8 azaphilonoids, 11 amino acids, 4 nucleosides, 9 lipid acids, 4 phytosterols and glycerol. The preliminary screening showed that ergosterol remarkably reduced cholesterol levels in zebrafish larvae. Moreover, ergosterol delayed body weight gain and decreased circulating total cholesterol, triglyceride, low density lipoprotein cholesterol levels in high fat diet-fed mice. Ectopic lipid accumulation was also ameliorated in the liver and heart of obese mice. CONCLUSION: Global analysis of chemical components and screening of lipid-lowering non-monacolin compounds in MFRP have improved our understanding of its therapeutic material basis.

Rapid separation and identification of multiple constituents in Danhong Injection by ultra-high performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight tandem mass spectrometry.

To characterize and identify multiple constituents in Danhong injection (DHI), a fast ultra-high performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC-ESI-QTOF/MS) method was established and validated in the present study. A total of 63 compounds, including 33 phenolic acids, 2 C-glycosyl quinochalcones, 6 flavonoid O-glycosides, 4 iridoid glycosides, 6 organic acids, 5 amino acids, and 3 nucleosides, were identified or tentatively characterized. In conclusion, the UHPLC-ESI-QTOF/MS method is useful and efficient for in-depth structural elucidation of chemical compounds in complex matrices of herbal medicines such as DHI.