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Objective:To investigate the whole genome of SARS-CoV-2 causing COVID-19 in Rongcheng city of Shandong Province in May 2022 and to further analyze the nucleotide and amino acid variations for source tracing.Methods:High-throughput sequencing was used to sequence the SARS-CoV-2 genome in 15 nasopharyngeal swab samples from COVID-19 cluster infections and three environmental samples related to an aquatic product import company. Whole-genome sequence splicing, variant site analysis and sequence typing were performed on the raw sequencing data using virus sequence and variant analysis software. A phylogenetic tree was constructed by evolutionary analysis software. Epidemiological investigation was used to trace the potential source of infection.Results:Thirteen whole genome sequences of SARS-CoV-2 with the length ranging from 29 653 bp to 29 780 bp were successfully obtained from the nasopharyngeal swab samples. The average sequencing depth was 1 756-6 565 X and the genome coverage was 99.20%-99.63%. The results of Pangolin typing showed that the 13 genomes belonged to the VOC/Gamma (P.1.15) evolutionary branch. Compared with the Wuhan reference strain (NC_045512.2), the 13 genome sequences had 40-41 nucleotide mutation sites. There were 23-24 amino acid variation sites in seven protein domains (ORF1a, ORF1b, S, ORF3a, ORF8, ORF9b and N proteins). Evolutionary analysis showed that the viral sequence was grouped to the same subclade as the reference strain from Argentina (EPI_ISL_4082233).Conclusions:In this study, the whole genome sequences of 13 Gamma variant strains were obtained from COVID-19 cluster infections associated with imported cold-chain aquatic products in Rongcheng city, and the imported seafood from South America in 2021 was found to be the source of the virus in a timely manner. This study provided reference for the SARS-CoV-2 variant analysis and case tracing and also suggested that the survival and transmission ability of SARS-CoV-2 on the surface of cold-chain products should not be underestimated and needed further investigation.
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In order to provide guidance for the protection and utilization of resources,quality control and breeding of improved varieties,we compared the main phenotypic characters and quality of wild and transplanted Paris polyphylla var. yunnanensis collected from different producing areas. Seven phenotypic characters of 33 samples of P. polyphylla var. yunnanensis collected from Yunnan,Guizhou and Sichuan were determined by conventional methods,and the principal component analysis and cluster analysis were used to analyze the diversity of the samples. The parissaponin( polyphyllin Ⅰ,Ⅱ,Ⅵ,Ⅶ) content of the samples were detected by HPLC,and analyzed by cluster analysis. Correlation analysis of the phenotypic characters and the parissaponin content was performed. There were significant differences in seven phenotypic characters between wild and transplanted samples of P. polyphylla var. yunnanensis from different habitats,with high phenotypic diversity and abundant genetic variation. The results of principal component analysis showed that leaf shape index was the main factor of morphological variation of P. polyphylla var. yunnanensis. Cluster analysis showed that the phenotypic characters of wild and transplanted P. polyphylla var. yunnanensis could not be completely separated. The content of saponins in wild and transplanted samples from different habitats was quite different. Saponins content of 93. 94% samples met the criterion of Chinese Pharmacopoeia 2015 edition,and the overall quality was relatively steady. The results of independent sample t-test showed that there was no significant difference of all the active ingredient between wild and transplanted samples,and it couldn't be used to distinguish between wild and transplanted samples. It is the same as the results of cluster analysis. The results of correlation analysis showed that the phenotypic traits of P. polyphylla var. yunnanensis were correlated with its medicine quality,and the total content of saponins was positively correlated with leaf length and leaf shape index( r = 0. 389,0. 441; P<0. 05). Yunnan,Guizhou and Sichuan are suitable for the growth of P. polyphylla var. yunnanensis. And the transplaned P. polyphylla var. yunnanensis can be used as the same as the wild ones completely. The results provide reference for the protection and selective breeding of P. polyphylla var. yunnanensis.
Subject(s)
China , Chromatography, High Pressure Liquid , Ecosystem , Melanthiaceae , Chemistry , Phytochemicals , Plant Breeding , Plant Leaves , Plants, Medicinal , Chemistry , SaponinsABSTRACT
Vitreoscilla haemoglobin (VHb) expression in heterologous host was shown to enhance growth and oxygen utilization capabilities under oxygen-limited conditions. The exact mechanism by which VHb enhances the oxygen utilization under oxygen-limiting conditions is still unknown. In order to understand the role of VHb in promoting oxygen utilization, changes in the total protein profile of E. coli expressing the vgb gene under its native promoter was analysed. Two-dimensional difference gel electrophoresis (2D DIGE) was employed to quantify the differentially expressed proteins under oxygen-limiting conditions. Overexpression of proteins involved in aerobic metabolic pathways and suppression of proteins involved in non-oxidative metabolic pathways shown in this study indicates that the cells expressing VHb prefer aerobic metabolic pathways even under oxygen limitation. Under these conditions, the expression levels of proteins involved in central metabolic pathways, cellular adaptation and cell division were also found to be altered. These results imply that Vitreoscilla haemoglobin expression alters aerobic metabolism specifically, in addition to altering proteins involved in other pathways, the significance of which is not clear as of now.
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Bibliometrics analysis has been made on the statistics of Chinese books circulation and order data through Chongqing Medical University. Goldlib Library Management System. And analysis relativity and variation between circulation needs and resource allocation for the past 10 years has also been made.
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Objective To assess the sequence variations in preS/S regions of occult hepatitis B virus (OHB) and their relationship to severe chronic hepatic injury. MethodsWe collected samples from HBsAg negative patients, and evaluated their HBV-DNA by nest-PCR. HBV-DNA positive samples were used for analysis of preS/S region by PCR sequencing. Results Sixty-nine cases with HBV-DNA were identified in 468 cases without HBsAg. The positive percents were 16％, 8.7％, 36.4％, 18.3％ and 0％in group of only HBcAb positive, only HBeAb positive, only HBeAg positive, both HBcAb and HBsAb positive and all indexes negative, respectively. The level of HBV-DNA of OHB was significant lower than that in HBsAg positive patients. Compared with HBsAg positive controls, preS/S deletion, M1I and Q2K in preS2 region, Q129N/R/P,G185R and S210R in S region were more common in OHB. Moreover, M1I and Q2K in preS2 region, G185R and S210R in S region in OHB with severe chronic hepatic injury were more common that those in OHB without severe chronic hepatic injury. Compared with HBsAg positive patients with severe chronic hepatic injury, the level of HBV-DNA was lower, while the frequency of M1I and Q2K mutation in preS2 region, G185R and S210R in S region were more common in OHB patients with severe chronic hepatic injury. ConclusionThe virological factors were different between OHB and HBsAg positive patients. The M1I and Q2K in preS2 region, G185R and S210R in S region might be useful for prognosis evaluation of OHB patients.