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.

Objective To investigate whether endoscopic ultrasonography (EUS) can be an alternative method for diagnostic endoscopic retrograde cholangiopancreatography (ERCP) by comparing the ability of EUS versus CT and transabdominal ultrasonography (TUS) in the diagnosis of muddy stones of the common bile duct. Methods A prospective study was conducted for 53 patients suspected of muddy stones of the common bile duct who attended Nanxishan Hospital of Guangxi Zhuang Autonomous Region from July 2019 to December 2021, and all patients underwent EUS, TUS, and CT before ERCP. With ERCP and endoscopic sphincterotomy (EST) for removing muddy stones of the common bile duct as the gold standard for the diagnosis of muddy stones of the common bile duct, EUS, TUS, and CT were compared in terms of their ability to display the muddy stones of the common bile duct. The chi-square test or the Fisher's exact test was used for comparison of categorical data between groups. Results In the 53 patients, EUS, TUS, and CT had a positive rate of 88.68%, 50.94%, and 62.26%, respectively, in detecting muddy stones of the common bile duct. As for the positive results confirmed by EST under ERCP, EUS had a sensitivity of 93.75%, a specificity of 60.00%, and an accuracy of 90.57% in detecting muddy stones of the common bile duct, while TUS had a sensitivity of 56.25%, a specificity of 100.00%, and an accuracy of 60.38% and CT had a sensitivity of 66.67%, a specificity of 80.00%, and an accuracy of 67.92%. There was a significant difference between EUS and CT in the accuracy in detecting muddy stones of the common bile duct ( χ 2 =8.26, P =0.004), and there was also a significant difference in diagnostic accuracy between EUS and TUS ( χ 2 =13.05, P < 0.001). Conclusion EUS is more accurate than TUS and CT in the diagnosis of muddy stones of the common bile duct, and instead of ERCP, EUS is thus recommended for suspected muddy stones of the common bile duct when TUS and CT fail to identify the lesions in clinical practice, so as to make a confirmed diagnosis and reduce related costs and complications.

Objective:To analyze the expression of cell division cycle associated protein 5 (CDCA5) in pancreatic cancer tissues and its correlation with prognosis based on the bioinformatics.Methods:The RNA sequencing data (HTSeq-FPKM) and corresponding clinical information of 168 pancreatic cancer samples from January to December 2021 were downloaded from the Cancer Genome Atlas (TCGA) database, and the data of 179 pancreatic patients from January to December 2021 were downloaded from the GEPIA2 database, and 171 normal pancreatic tissues from TCGA and GTEx databases were simultaneously integrated. The relative expression level of CDCA5 mRNA in pancreatic cancer patients in GEPIA2 database and its relationship with overall survival (OS) and disease-free survival (DFS) were explored. Combined with the clinical data of the patients, univariate and multivariate Cox regression model analysis was used to analyze the factors influencing the OS of pancreatic cancer patients. Gene set enrichment analysis (GSEA) was performed to investigate the possibly involved signal pathways of CDCA5 in pancreatic cancer.Results:In the GEPIA2 database, the relative expression level of CDCA5 mRNA in pancreatic cancer tissues was higher than that in normal pancreatic tissues, and the difference was statistically significant ( P < 0.05). The pancreatic cancer patients were divided into the high CDCA5 mRNA expression group (89 cases) and the low CDCA5 mRNA expression group (89 cases) according to the median of relative expression level of CDCA5 mRNA (the case equal to the median value was not subgrouped). Survival analysis showed that patients with high CDCA5 mRNA expression had shorter OS ( P = 0.024) and DFS ( P = 0.025) compared with those with low CDCA5 mRNA expression. Multivariate Cox analysis showed that in TCGA database, N staging ( HR = 2.15, 95% CI 1.24-3.72, P = 0.006) and CDCA5 expression ( HR = 1.71, 95% CI 1.23-2.38, P = 0.001) were independent influencing factors of OS for pancreatic cancer patients. The results of GSEA enrichment analysis indicated that high CDCA5 mRNA expression was enriched in 13 biological pathways [all P < 0.05, false discovery rate (FDR) < 0.005] including cell cycle, DNA replication, homologous recombination, pyrimidine metabolism, mismatch repair, pentose phosphate pathway, glycolysis gluconeogenesis and p53. The expression of CDCA5 mRNA was positively correlated with the expressions of HK2, PKM, PGK1, ALDOA, EN01 and LDHA (all P < 0.05). Conclusions:CDCA5 is highly expressed in pancreatic cancer tissues and is associated with poor prognosis of patients, and it can be used as a prognostic marker for pancreatic cancer.

Pyroptosis is a newly discovered programmed cell death that can lead to inflammatory response, its occurrence depends on the sequential activation of inflammatory bodies and caspase, and then the pore-forming generated by the fragmentation of gasdermin D and its cell membrane polymerization. Pyroptosis is mainly comprised of the pathway that depends on caspase-1 activated by flammasomes and the non-classical pathway that depends on caspase-4/5/11 activated by cytoplasmic lipopolysaccharide. As an important mechanism mediating the inflammatory response of the body, pyroptosis plays an irreplaceable role in the body's response to noxious stimuli, which is closely related to many diseases such as nervous system diseases, cardiovascular system diseases and tumors. Recent studies have found that pyroptosis also plays a key role in the occurrence of intestinal ischemia-reperfusion (II/RI). This paper reviews the molecular characteristics, mechanism of pyroptosis and its relationship with II/RI in recent years, in order to provide theoretical basis for the prevention and treatment of II/RI.

Objective:To explore the association between resting heart rate(RHR) and all-cause mortality among the Chinese oldest-old aged more than 80.Methods:Using a total of seven surveys or follow-ups data (1998, 2000, 2002, 2005, 2008, 2011 and 2014) from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 17 886 elderly over 80 years old were selected as subjects, their resting heart rate were measured though baseline survey and the survival outcome and death time of the subjects were followed up. The subjects were divided into 6 groups according to their resting heart rate. Cox regression model was used to estimate the effect of resting heart rate on mortality risk. The interaction of age, gender and resting heart rate was also analyzed by likelihood ratio test.Results:The age of subjects M( P25, P75) was 92 (86, 100) years old, including 10 531 females (58.9%) and there were 13 598 participants died, the mortality rate was 195.5 per 1 000 person-years. Multivariate Cox regression analysis showed that compared to the control group (60-69 pbm/min), the hazard ratio of the elderly are 1.06 (95% CI: 1.02, 1.11), 1.09 (95% CI: 1.04, 1.15), 1.23 (95% CI: 1.14, 1.34), 1.25 (95% CI: 1.08, 1.44) in the group of RHR between 70-79, 80-89, 90-99 and ≥100 pbm/min and Pvalues are all less than 0.05. Likelihood ratio test showed that RHR and age had an interaction effect. ( P for interaction=0.011). Conclusion:The risk of all-cause death increased with the increase of resting heart rate and this relationship was stronger between the 80-89 years old people.

Objective:To explore the association between resting heart rate(RHR) and all-cause mortality among the Chinese oldest-old aged more than 80.Methods:Using a total of seven surveys or follow-ups data (1998, 2000, 2002, 2005, 2008, 2011 and 2014) from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 17 886 elderly over 80 years old were selected as subjects, their resting heart rate were measured though baseline survey and the survival outcome and death time of the subjects were followed up. The subjects were divided into 6 groups according to their resting heart rate. Cox regression model was used to estimate the effect of resting heart rate on mortality risk. The interaction of age, gender and resting heart rate was also analyzed by likelihood ratio test.Results:The age of subjects M( P25, P75) was 92 (86, 100) years old, including 10 531 females (58.9%) and there were 13 598 participants died, the mortality rate was 195.5 per 1 000 person-years. Multivariate Cox regression analysis showed that compared to the control group (60-69 pbm/min), the hazard ratio of the elderly are 1.06 (95% CI: 1.02, 1.11), 1.09 (95% CI: 1.04, 1.15), 1.23 (95% CI: 1.14, 1.34), 1.25 (95% CI: 1.08, 1.44) in the group of RHR between 70-79, 80-89, 90-99 and ≥100 pbm/min and Pvalues are all less than 0.05. Likelihood ratio test showed that RHR and age had an interaction effect. ( P for interaction=0.011). Conclusion:The risk of all-cause death increased with the increase of resting heart rate and this relationship was stronger between the 80-89 years old people.

Objective:To establish the minimum inhibitory concentration (MIC) detection method of Yersinia pestis by determining MIC of 11 kinds of antibiotics against Yersinia pestis, to master the inhibition range of common antibiotics on Yersinia pestis, and provide baseline data for clinical treatment of plague. Methods:According to Clinical Labor Standard Institution (CLSI), the agar plate dilution method was used to determine the MIC of 11 kinds of antibiotics against 118 strains of Yersinia pestis, including ofloxacin, ciprofloxacin, trimethoprim-sulfamethoxazole, kanamycin, streptomycin, ceftriaxone, ampicillin, chloramphenicol, spectinomycin, cefuroxime and tetracycline. MIC 50 and MIC 90 (the minimum concentration of drug which could inhibit 50% and 90% of bacterial growth) were calculated. The consistency was observed by comparing the results with those of the disk diffusion method. One hundred and eighteen strains of Yersinia pestis were isolated from natural plague foci of Qinghai Province and preserved by Qinghai Institute for Endemic Disease Prevention and Control. Results:Among 118 strains of Yersinia pestis tested, no single or multiple strains of Yersinia pestis resistant to 11 kinds of antibiotics were found, which was consistent with the results of the disk diffusion method. The MIC 50 and MIC 90 of 11 kinds of antibiotics against 118 strains of Yersinia pestis were obtained. Conclusions:The MIC detection method of Yersinia pestis is successfully established. This method can be used to measure the MIC of antibiotics against Yersinia pestis in high throughput and evaluate the sensitivity of Yersinia pestis to antibiotics. It is an efficient, economical and practical experimental method.

Objective To explore the clinicopathological characteristics,diagnosis,treatment and prognosis of accessory breast cancer.Methods Clinical and pathological data of 37 accessory breast cancer patients from Dec 2005 to Aug 2017 were reviewed.Results 12 patients underwent breast-conserving local wide excision plus axillary lymph node dissection.5 cases were treated by segmental resection and 19 patients by Auchincloss or Halsted mastectomy;One patient abandoned surgery.The most common histological type of accessory breast cancer was infiltrating ductal carcinoma (26 cases,70.3％) followed by adenocarcinoma (4 cases) and miscellaneous type (7 cases).The most common AJCC pathological stages were stage Ⅱ (n =24,65 ％),Ⅰ (n =8),Ⅲ(n =3) and Ⅳ (n =2).The median follow-up time was 6 (1-12) years,the followup rate was 100％.Until Dec 2017,7 patients died from metastasis and the others were alive.Conclusions Accessory breast cancer is rare and with poor prognosis.The diagnosis depends on clinical manifestations,imaging and pathology.Surgery is the mainstay therapy,adjuvant chemo therapy is recommanded.

Randomization is the key to ensure the balance of confounders between the comparison groups in clinical trials, and it is the statistical basis for making the study results comparable. A simple randomization in a clinical trial with large sample-size allows for a balanced comparison of the number of subjects and confounding factors between groups, but in a clinical trial with small sample-size, it is necessary to use a restricted randomization method (the blocked randomization). Block randomization ensures that the number of subjects between groups is basically equal, maximize the effectiveness of clinical trials as the standard error of the treatment-effect estimate is decreased, which affords big rewards in scientific accuracy and credibility.

Objective In order to acquaint with the prevalence of Tibetan sheep plague in this area, we conducted a serum epidemiological investigation of Tibetan sheep plague in Qinghai Province. Methods Indirect hemagglutination assay (IHA) and colloidal gold immunochromatography (GICA) were applied to test serum samples of Tibetan sheep and whole blood samples from jugular vein of Tibetan sheep were collected in 8 Prefectures of Qinghai Province from 2013 to 2016. Results A total of 86 positive Tibetan sheep serum samples with plague F1 antibody were detected by both methods, and the positive rate was 0.68％ (86/12710), the samples collected in Xinghai County Hainan Prefecture had the highest positive rate, which was 5.20％ (27/519). The Haixi Prefecture and Yushu Prefecture were historical epidemic areas, the positive rates were 0.65％(15/2313) and 0.26％(6/2293), respectively. Hainan Prefecture, Guoluo Prefacture and Huangnan Prefecture were newly confirmed epidemic areas, the positive rates were 1.61％ (28/1741), 1.01％ (15/1481), and 1.44％(19/1316), respectively. The antibody titers were 1:20 to 1:5120, the samples collected in Maqin County Guoluo Prefecture had the highest titer, namely 1 :5120. Conclusions In Qinghai Province, Tibetan sheep plague is endemic, and there are outbreaks in some regions. So we have to enhance the Tibetan sheep plague monitoring especially in Marmot plague epidemic area.