Objective:To study the clustered regularly interspaced short palindromic repeats (CRISPR) genotype of Yersinia pestis and its regional distribution characteristics in natural plague focus of Tibet Autonomous Region. Methods:A total of 125 representative Yersinia pestis strains isolated from natural plague focus in Tibet Autonomous Region at different times, regions, hosts and vectors were selected as experimental strains, and the phenol chloroform mixed extraction method was used to extract Yersinia pestis DNA. Three pairs of CRISPR primers (for YPa, YPb, YPc locus) were used to amplify the DNA of the experimental strains, and the CRISPR genotype of Yersinia pestis was determined by sequencing. Results:All 125 strains of Yersinia pestis had three CRISPR locus: YPa, YPb, and YPc. A total of 18 spacer were found, including 8 in YPa loci, 6 in YPb loci, and 4 in YPc loci. Two new types of spacers had been discovered, namely b52 and c14. CRISPR typing revealed 10 genotypes, including G1, G7, G7-b4''', G7-b52, G7-c2 -, G8, G22, G22-a4 -, G22-b4''', and G22-c14, of which 6 were newly discovered genotypes. Among the 125 experimental strains, G7 was the main genotype, accounting for 65.6% (82/125), which was distributed in 6 prefecture level citys and 1 region of Tibet Autonomous Region. Next were G22 and G7-c2 - genetypes, accounting for 14.4% (18/125) and 11.2% (14/125), respectively. G22 gene type was distributed in Nagqu, Changdu, Lhasa citys, and Ngari Prefecture, while G7-c2 - genetype was distributed in Shigatse and Shannan cities. Conclusion:The CRISPR locus of Yersinia pestis in natural plague focus of Tibet Autonomous Region is highly polymorphic, and the Yersinia pestis strains with different genotypes have obvious regional distribution characteristics.

Background/Aims: Chronic hepatitis C (CHC) patients who failed antiviral therapy are at increased risk for hepatocellular carcinoma (HCC). This study assessed the potential role of metformin and statins, medications for diabetes mellitus (DM) and hyperlipidemia (HLP), in reducing HCC risk among these patients. Methods: We included CHC patients from the T-COACH study who failed antiviral therapy. We tracked the onset of HCC 1.5 years post-therapy by linking to Taiwan’s cancer registry data from 2003 to 2019. We accounted for death and liver transplantation as competing risks and employed Gray’s cumulative incidence and Cox subdistribution hazards models to analyze HCC development. Results: Out of 2,779 patients, 480 (17.3%) developed HCC post-therapy. DM patients not using metformin had a 51% increased risk of HCC compared to non-DM patients, while HLP patients on statins had a 50% reduced risk compared to those without HLP. The 5-year HCC incidence was significantly higher for metformin non-users (16.5%) versus non-DM patients (11.3%; adjusted sub-distribution hazard ratio [aSHR]=1.51; P=0.007) and metformin users (3.1%; aSHR=1.59; P=0.022). Statin use in HLP patients correlated with a lower HCC risk (3.8%) compared to non-HLP patients (12.5%; aSHR=0.50; P<0.001). Notably, the increased HCC risk associated with non-use of metformin was primarily seen in non-cirrhotic patients, whereas statins decreased HCC risk in both cirrhotic and non-cirrhotic patients. Conclusions Metformin and statins may have a chemopreventive effect against HCC in CHC patients who failed antiviral therapy. These results support the need for personalized preventive strategies in managing HCC risk.

Abstract: Objective To understand the phenotypic and genetic characteristics of Yersinia pestis strains isolated from Himalayan marmot natural focus area and domestic rat plague focus area in southern China, and provide reference for mastering the pathogenic characteristics of Yersinia pestis of two plague foci. Methods A total of 412 of Yersinia pestis strains isolated from Himalayan marmot plague focus and domestic rat plague focus of southern China were subjected to to sorbitol fermentation assays, virulence factor, different region (DFR) typing, and clustered regularly interspaced palindromic repeats (CRISPR) typing. Results The biochemical types of Y. pestis from the two plague foci showed distinct regional distribution features. Five biochemical phenotypes were identified in Yersinia pestis isolated from Himalayan marmot natural focus area, while only one biochemical phenotype was identified in strains isolated from the domestic rat plague focus of Southern China. Most of the Yersinia pestis isolated from the two plague foci were capable of producing the virulence factors of Fl and PstI. Among the strains from Himalayan marmot focus, 70.53% (201/285) were VW-positive, 75.09% (214/285) were Pgm-positive, 20.00% (57/285) of the strains were Pgm-negative, and 5.26% (15/285) were Pgm mixed-type strains. Among strains from domestic rat plague focus of southern China, 37.80% (48/127) were VW-positive, 29.13% (37/127) were Pgm-positive, 58.27% (74/127) were Pgm-negative, and 12.60% (16/127) were Pgm mixed-type strains. DFR typing revealed 22 genotypes of Y. pestis from the Himalayan marmot plague focus, with the main genotypes being type 5, 7, 8, 10, 19, 32 and 49. All strains from domestic rat plague focus area in southern China belonged to type 9. CRISPR typing revealed that all strains from the Himalayan marmot natural focus were classified into 7 CRISPR gene clusters and 14 CRISPR genotypes, with the main genotypes being G7, G22, G26-a1'and G22-A1'. All strains from domestic rat plague focus area in southern China belonged to CRISPR genotype G30, with the gene cluster being Ca8. Conclusions The phenotypes and genotypes of the Yersinia pestis of Himalayan marmot plague focus are diverse, with an obvious characteristics of geographical distribution. The phenotype and genotype of the Yersinia pestis of domestic rat plague focus of Southern China are single. DFR and CRISPR genotyping methods with phenotypic characteristics can effectively identify the Yersinia pestis isolated from the two plague foci, thereby meeting the needs of identification and traceability research.

To identify the bitter compounds of real-world Xiaoer Ganmao Oral Liquid sugar-free intermediates, an integrated strategy has been developed by using ultra-high performance liquid chromatography with linear ion trap-Orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MSⁿ) method and BitterX database prediction. The chromatographic operating conditions were as follows, chromatographic column: Acquity UPLC BEH C₁₈ (100 mm × 2.1 mm, 1.7 μm), mobile phase: 0.1% formic acid-water solution (A)-acetonitrile (B) with gradient elution. The data were collected in positive and negative ion modes, respectively. The accurate molecular mass and structural information of the target compounds were obtained based on quasi-molecular ions and fragmentation ions provided by high-resolution mass spectrometry. The compounds were identified by combining retention time, reference substances, reports, and other relevant data, and a total of 57 constituents including flavonoids, alkaloids, and phenylpropanoids were finally identified. Further, the BitterX database was used to predict binding probability of compounds to bitter receptors and identify potential bitter critical quality attributes, finally 33 potential bitter compounds, including kukoamine A and linarin, were predicted. This study comprehensively characterized the material basis of Xiaoer Ganmao Oral Liquid sugar-free intermediates, it provides an effective method for bitter compound screening and a reference for further improving the undesirable taste of Xiaoer Ganmao Oral Liquid.

OBJECTIVE: To evaluate the feasibility and tolerability of metoprolol standard dosing pathway (MSDP) in Chinese patients with acute coronary syndrome (ACS). METHODS: In this multicenter, prospective, open label, single-arm and interventional study that was conducted from February 2018 to April 2019 in fifteen Chinese hospitals. A total of 998 hospitalized patients aged ≥ 18 years and diagnosed with ACS were included. The MSDP was applied to all eligible ACS patients based on the standard treatment recommended by international guidelines. The primary endpoint was the percentage of patients achieving the target dose at discharge (V2). The secondary endpoints included the heart rate and blood pressure at V2 and four weeks after discharge (V4), and percentage of patients experiencing bradycardia (heart rate < 50 beats/min), hypotension (blood pressure < 90/60 mmHg) and transient cardiac dysfunction at V2 and V4. RESULTS: Of the 998 patients, 29.46% of patients achieved the target dose (≥ 95 mg/d) at V2. The total population was divided into two groups: target group (patients achieving the target dose at V2) and non-target group (patients not achieving the target dose at V2). There was significant difference in the reduction of heart rate from baseline to discharge in the two groups (-4.97 ± 11.90 beats/min vs. -2.70 ± 9.47 beats/min, P = 0.034). There was no significant difference in the proportion of bradycardia that occurred in the two groups at V2 (0 vs. 0, P = 1.000) and V4 (0.81% vs. 0.33%, P = 0.715). There was no significant difference in the proportion of hypotension between the two groups at V2 (0.004% vs. 0.004%, P = 1.000) and V4 (0 vs. 0.005%, P = 0.560). No transient cardiac dysfunction occurred in two groups during the study. A total of five adverse events (1.70%) and one serious adverse event (0.34%) were related to the pathway in target group. CONCLUSIONS In Chinese ACS patients, the feasibility and tolerability of the MSDP have been proved to be acceptable.

Abstract: Objective　To investigate the clustered regularly interspaced short palindromic repeats (CRISPR) genotypes and regional distribution of Yersinia pestis strains in the natural plague foci of Hainan Tibetan Autonomous Prefecture of Qinghai Province (referred to as "Hainan prefecture") and provide a scientific basis for plague prevention and control in this area. Methods　A total of 36 representative Yersinia pestis strains, which were isolated from different host animals and insect vectors from 1954 to 2009 in Hainan Prefecture, were selected as experimental subjects. The DNAs were extracted using the traditional sodium dodecyl sulfate decomposition and phenol-chloroform method. Three pairs of CRISPR primers (YPa, Ypb, YPc) were used for PCR amplification, sequencing and analysis of the DNA of the tested strains, respectively, as a means to identify the CRISPR genotypes of Yersinia pestis in Hainan Prefecture. Results　A total of 17 spacers were observed among 36 strains of Yersinia pestis, including 9 of YPa, 5 of YPb and 3 of YPc. All strains were divided into 5 CRISPR gene clusters (Cb2, Cb4 ', Ca7, Ca7 ', Ca35 ') and 6 genotypes (G1, G9, G22, G22-A1 ', G26-A1 ', G26-A1 'A4 -). The G26-a1 ' was the main genotype, which was distributed in Gonghe, Guide and Xinghai County, and the G22 is the second type, which was distributed in Gonghe and Guide County. Conclusions　The genetic polymorphism of CRISPR loci of Yersinia pestis strains in Hainan was high, and the regional distribution characteristics of Yersinia pestis strains with different genotypes were significant.

Abstract: Objective To investigate the current status of streptomycin resistance of Yersinia pestis caused by point mutations of rpsL gene in Qinghai, so as to provide theoretical basis for precise clinical medication and prevention of drug resistance of human plague outbreak in South area of Qinghai Province in the future. Methods A total of 104 representative strains of Yersinia pestis collected from plague patients, vector insects and intermediate hosts in South area of Qinghai Province from 1957 to 2009 were screened, isolated and cultured by Hiss agar plates. The DNA of representative Yersinia pestis was extracted by sodium dodecyl sulfate lysis and phenol-chloroform method. The primers forward primer and reverse primer and TaqMan-MGB probes probe1 [FAM] and probe2 [VIC] were designed for the rpsL gene of streptomycin resistance gene in China. Real-time PCR with TaqMan-MGB fluorescent probe was used to detect the mutations of rpsL gene in streptomycin resistance locus of 104 strains of Yersinia pestis in South area of Qinghai Province. Results The FAM test results of 104 strains in South area of Qinghai Province were positive, corresponding to the detection of rpsL (128 : A ), RFU peak >1 000,negative <200. VIC test results of all tested strains were negative, corresponding to the detection of rpsL (128:G), RFU peak <200, positive >1 000. That is, no strains with rpsL gene mutation related to streptomycin resistance were found in the 104 strains of Yersinia pestis in Qingnan Province. Conclusion This study provides basic data on the distribution of streptomycin resistance of Yersinia pestis in South area of Qinghai Province, and lays a foundation for preventing the occurrence of drug resistance and clinical treatment of Yersinia pestis in South area of Qinghai Province.

Objective: To explore the composition of bacteria in lower respiratory tract of patients with pneumoconiosis and dust exposure, and to compare and analyze the difference and correlation between them. Methods: From May 2020 to January 2021, a prospective multicenter cross-sectional study was conducted to select patients with pneumoconiosis who underwent bronchoalveolar lavage treatment at the Respiratory and Critical Care Medical Department of the 920th Hospital of the Joint Support Force and the Respiratory Department of Tongren Hospital in Kunming, as well as the population of dust recipients. A total of 24 patients with pneumoconiosis (pneumoconiosis group) were included, and 16 dust exposed individuals (dust exposed group) were used as controls. Two groups of patients' alveolar lavage fluid were collected. The 16SrRNA gene V3-V4 sequencing technology and bioinformatics analysis platform were used to measure and analyze the differences in microbial structure composition and associations between bacterial communities. Results: Compared with the dust exposed group, the top 5 bacterial phyla in the alveolar lavage fluid level of patients with pneumoconiosis were the same, followed by Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria. Compared with the dust exposure group, the pneumoconiosis group patients belong to the top 5 genera of horizontal flora abundance, which are different. The dust exposure group is respectively: Pseudomonas, Proctor, Streptococcus, Achromobacter, and Neisseria. The pneumoconiosis group is respectively: Pseudomonas, Achromobacter, Streptococcus, Ralstonia, and Proctor. The Alpha diversity analysis results showed that compared with the dust exposed group, the level of bacterial diversity in the pneumoconiosis group was difference (P<0.05), and there was no statistically significant difference in bacterial evenness (P>0.05) ; Beta diversity showed differences in microbial community structure between the two groups (P<0.05 ). Single factor microbial association network analysis showed that there was a high correlation between Firmicutes and Bacteroidetes in the pneumoconiosis and dust exposed groups and other species, showing a positive correlation; The correlation between Proteobacteria and other species is high, showing a negative correlation. Conclusion: The structure and relative abundance of bacteria in lower respiratory tract were different between patients with pneumoconiosis and dust exposure, and the diversity of bacteria in lower respiratory tract increased in patients with pneumoconiosis, which may be related to disease status.
Humans ; Cross-Sectional Studies ; Prospective Studies ; Pneumoconiosis ; Bacteria/genetics* ; Dust ; Respiratory System

Objective:To learn about the clustered regularly interspaced short palindromic repeats (CRISPR) genotyping of Yersinia pestis in Yushu Tibetan Autonomous Prefecture (Yushu for short), Qinghai Province, and to explore its genetic characteristics. Methods:In this study, 44 representative strains isolated from local natural plague focus in Yushu from 1963 to 2007 were selected as experimental objects to extract DNA. Primers targeting the three CRISPR loci (YPa, YPb, and YPc) were designed for PCR amplification. The amplified products were sequenced and analyzed to identify the CRISPR spacer, and to determine the CRISPR genotypes and clusters.Results:Twenty-three spacers including 14 of YPa, 6 of YPb and 3 of YPc were observed among 44 strains, of which 2 spacers (a106 and a107) were firstly identified. According to the spacer arrays, the strains were divided into 15 CRISPR genotypes and classified into 6 CRISPR clusters which were Cb4, Cc3', Ca7, Ca7', CaΔ5' and Ca35', respectively. Among them, Ca7 was the most epidemic dominant cluster (34 strains) in Yushu.Conclusion:The CRISPR loci of Yersinia pestis in Yushu have multiple genotypes, high genetic polymorphism, and complex population structure.

Objective:To study the phenotype and genotype distribution of Yersinia pestis ( Y. pestis) in different natural foci of plague in China, so as to provide scientific basis for plague prevention and control. Methods:A total of 2 184 strains of Y. pestis isolated from different time periods, regions, hosts and vectors in 11 plague natural foci of China since 1943 were selected for biochemical type identification, glycolysis test, virulence factor test [capsule antigen (F1), pesticin Ⅰ (Pst Ⅰ), virulence antigen factor (VWa), pigmentation factor (Pgm)], different region (DFR) typing and clustered regularly interspaced short palindromic repeats (CRISPR) typing. Results:There were 16 biochemical types of Y. pestis in the natural foci of plague in China, and each biochemical type showed obvious regional distribution in each foci. Most strains were positive for ass hide glue glycolysis (89.79%, 1 961/2 184), maltose (80.13%, 1 750/2 184), glycerol (94.23%, 2 058/2 184), and denitrification (82.78%, 1 808/2 184), and negative for rhamnose (88.78%, 1 939/2 184) and melibiose (85.62%, 1 870/2 184). Virulence factor test results showed that 99.95% (2 183/2 184) of Y. pestis were F1 positive; 99.73% (2 178/2 184) of Y. pestis can produce Pst Ⅰ; 73.31% (1 601/2 184) of Y. pestis were VWa positive and 26.69% (583/2 184) were VWa negative; Pgm positive strains accounted for 72.62% (1 586/2 184), Pgm negative strains accounted for 21.52% (470/2 184), and Pgm mixed type strains accounted for 5.86% (128/2 184). According to DFR typing results, there were 52 genotypes in 2 184 strains of Y. pestis, of which 19 were major genotypes and 33 were minor genotypes. CRISPR typing revealed 16 major genotypes, of which 7 were newly discovered. Conclusion:The phenotypes and genotypes of Y. pestis in various natural foci of plague in China are diverse and have geographical distribution characteristics.