Objective To investigate the virulence and drug resistance characteristics of diarrheagenic Escherichia coli isolated from patients with infectious diarrhea in our hospital.Methods The preliminary identification of microbes was carried out by the VITEK-MS microbial mass spectrometry detection system and virulence genes were detected by the multiplex real-time PCR.Five types of diarrhea-genic Escherichia coli(DEC)clinically isolated from patients with infectious diarrhea in our hospital were identified.The drug resist-ance characteristics of DEC strains were detected by the microbroth dilution and E-test.The drug-resistant molecular characteristics were analyzed by the next-generation sequencing and bioinformatics.The Fisher exact probability method was used for statistical analy-sis.Results The detection rate of DEC in our hospital was 11.9%,with enteroaggregative E.coli(EAEC)accounting for 37.5%,a-typical enteropathogenic Escherichia coli(EPEC)accounting for 34.38%,enterotoxigenic E.coli(ETEC)accounting for 25.0%,and enteroinvasive E.coli(EIEC)accounting for 3.12%.None of enterohemorrhagic E.coli(EHEC)strain was detected.The resistance rates of 32 DEC strains to ampicillin,tetracycline,and trimethoprim/sulfamethoxazole were 53.12%,43.75%,and 37.5%,respec-tively.ESBLs(+)strains accounted for 18.75%,and the detection rate of multidrug-resistant strains was 83.83%,significantly higher than that of ESBLs(-)strains(P=0.042).A total of 25 ST genotypes were obtained from 32 DEC strains.The dominant genotypes were ST10(4 strains,12.5%),followed by ST28(2 strains,6.25%),ST31(2 strains,6.25%),ST3153(2 strains,6.25%),and the other 21 genotypes(1 strain,3.13%).One carbapenem resistant strain carrying the blaNDM-1 gene was detected in EAEC.Conclu-sion Four virulence genes such as aggR,pic,astA,and eae,are more common in the DEC of patients with infectious diarrhea in our hospital,with EAEC and EPEC as the main subtypes.The genotypes are highly polymorphic,and multidrug-resistant strains have been detected.

Objective:To investigate the prospective association of sleep duration with the development of chronic obstructive pulmonary disease (COPD) in adults in Suzhou.Methods:The study used the data of 53 269 participants aged 30-79 years recruited in the baseline survey from 2004 to 2008 and the follow-up until December 31, 2017 of China Kadoorie Biobank (CKB) conducted in Wuzhong District, Suzhou. After excluding participants with airflow limitation, self-reported chronic bronchitis/emphysema/coronary heart disease history at the baseline survey and abnormal or incomplete data, a total of 45 336 participants were included in the final analysis. The association between daily sleep duration and the risk for developing COPD was analyzed by using a Cox proportional hazard regression model, and the hazard ratio ( HR) values and their 95% CI were calculated. The analysis was stratified by age, gender and lifestyle factors, and cross-analysis was conducted according to smoking status and daily sleep duration. Results:The median follow-up time was 11.12 years, with a total of 515 COPD diagnoses in the follow-up. After adjusting for potential confounders, multifactorial Cox proportional hazard regression analysis showed that daily sleep duration ≥10 hours was associated with higher risk for developing COPD ( HR=1.42, 95% CI: 1.03-1.97). The cross analysis showed that excessive daily sleep duration increased the risk for COPD in smokers ( HR=2.49, 95% CI: 1.35-4.59, interaction P<0.001). Conclusion:Longer daily sleep duration (≥10 hours) might increase the risk for COPD in adults in Suzhou, especially in smokers.

Acute pancreatitis (AP) is a devastating disease characterized by an inflammatory disorder of the pancreas. P-selectin glycoprotein ligand-1 (PSGL-1) plays a crucial role in the initial steps of the adhesive at process to inflammatory sites, blockade of PSGL-1 might confer potent anti-inflammatory effects. In this study, we generated two non-human primate derived monoclonal antibodies capable of efficiently targeting human PSGL-1, RH001-6 and RH001-22, which were screened from immunized rhesus macaques. We found that RH001-6, can effectively block the binding of P-selectin to PSGL-1, and abolish the adhesion of leukocytes to endothelial cells in vitro. In vivo, we verified that RH001-6 relieved inflammatory responses and pancreatic injury in both caerulein and l-arginine induced AP models. We also evaluated the safety profile after RH001-6 treatment in mice, and verified that RH001-6 did not cause any significant pathological damages in vivo. Taken together, we developed a novel non-human primate derived PSGL-1 blocking antibody with high-specificity, named RH001-6, which can interrupt the binding of PSGL-1 and P-selectin and attenuate inflammatory responses during AP. Therefore, RH001-6 is highly potential to be further developed into therapeutics against acute inflammatory diseases, such as AP.

Objective:This work aims to investigate the virulence features, spore formation and the resistance mechanisms of major sequence types (STs) of clinical Clostridium difficile isolates from nosocomial infectious diarrhea. Methods:Clostridium difficile isolates were prospectively collected from 816 loose stool samples of in patients with antibiotic associated diarrhea at the Beijing Friendship Hospital of Capital Medical University from September 2017 to September 2019. The main ST types ST81 (26 strains), ST8 (15 strains) and ST42 (14 strains) of C. difficile were used as experimental strains. The polymerase chain reaction (PCR) and enzyme-linked immunoassay (ELISA) were performed to detect toxin genes and toxin production of different C. difficile ST types, respectively. The count of the colony forming units (CFU) of the strains as conducted by using the brain-heart infusion (BHI) agar plates. The antimicrobial resistance patterns of the strains to eleven kinds of antibiotics were determined by agar dilution method. The antimicrobial resistance genes: gyrA, gyrB and ermB were amplified and sequenced from the stains. Mutations in the resistance genes were analyzed by sequencing. Measure data was compared by Kruskal Wallis Test, differences in the resistance rates in three group were compared using Fisher exact test. Results:ST81 strains were identified as the tcdA-tcdB+/ cdtA-cdtB-toxin type, ST8 and ST42 strains belonged to tcdA+tcdB+/ cdtA-cdtB-toxin type. The toxin production of ST42 strains (41.9) were higher than ST8 (2.4) and ST81 groups (0.83) (all P<0.001). The number of spore quantities of ST81, ST8 and ST42 strains were 494×10 5CFU/ml, 160×10 5CFU/ml and 166×10 5CFU/ml, respectively. The spore quantities of ST81 strains were much higher than that of ST81 and ST42 strains (all P<0.001). From the in vitro susceptibility test, 100% (26/26) ST81 strains were featured as multi-drug resistant (MDR), and they were resistant to moxifloxacin, ceftriaxone, erythromycin and clindamycin. The resistance rates of ST8 strain to moxifloxacin, erythromycin and clindamycin were 9/15, 11/15 and 11/15, respectively. ST81 strains had higher resistance rates to moxifloxacin, clindamycin and erythromycin, compared to ST8 strains ( P=0.001, P=0.005 and P=0.005). All ST42 strains were susceptible to ceftriaxone and 3/14 ST42 strains were resistant to moxifloxacin. ST81 strains had higher resistance rates to ceftriaxone and moxifloxacin than the ST42 strains (both P<0.001). The positive rate of ermB in ST81 strains (100%, 26/26) were higher the ST8 strains (11/15) ( P<0.005). Amino acid mutation analysis showed that ST81and ST8 stains had one amino acid substitution in both GyrA and GyrB, but the amino acid substitutions were different in GyrB between two ST types. ST81 strains had two point-mutations: Thr82 replaced by Ile in GyrA, and Asp426 replaced by Val in GyrB. ST8 strains had point-mutation: Thr82 replaced by Ile in GyrA; Asp426 replaced by Asn in GyrB. For ST42 strains, Thr82 was replaced by Ile in GyrA. Conclusions:ST81 and ST42 strains were MDR. ST81 had higher spore ability, whereas ST42 strains had more virulence. ST81 strains and most of ST8 strains had high level of fluoroquinolones resistance. It is important to supervise persistently these three ST genotypes to prevent further dissemination.

Objective To investigate the prevalence rate of occult HBV infection (OBI) in patients with autoimmune hepatitis (AIH) and the influence of OBI in the clinical condition and prognosis of AIH patients. Methods A total of 103 patients with a confirmed diagnosis of AIH who were admitted to Beijing YouAn Hospital from April 2012 to March 2019 were enrolled. Nested PCR and real-time PCR were used to confirm the diagnosis of OBI, and real-time PCR was used to measure HBV pgRNA. Clinical features, laboratory markers, and follow-up analysis of prognosis were compared between the OBI group with 24 patients and the non-OBI group with 79 patients. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U rank sum test was used for comparison of non-normally distributed continuous data between two groups; the chi-square test or the Fisher's exact test was used for comparison of categorical data between groups. The Kaplan-Meier method was used to plot survival curves, and the Cox regression model was used to perform univariate and multivariate analyses. Hazard ratio and its 95% confidence interval were calculated. Results The detection rate of OBI was 23.30% (24/103) in AIH patients, with an HBV DNA viral load of < 200 IU/mL, among whom 9 patients with OBI (9/24, 37.50%) were found to have HBV pgRNA in serum. Compared with the non-OBI group, the OBI group had a significantly higher positive rate of the three antibodies anti-HBs, anti-HBc, and anti-HBe ( χ 2 =5.906, P =0.016). The univariate analysis showed that OBI, hypoproteinemia, splenomegaly, and ascites were risk factors for adverse events in AIH (all P < 0.05) and were associated with disease progression, and the multivariate Cox regression analysis showed that hypoproteinemia and ascites were independent risk factors for adverse events (all P < 0.05). Conclusion There is a relatively high detection rate of OBI in AIH patients, and the presence of OBI may accelerate the progression of AIH.

SIRT6 belongs to the conserved NAD⁺-dependent deacetylase superfamily and mediates multiple biological and pathological processes. Targeting SIRT6 by allosteric modulators represents a novel direction for therapeutics, which can overcome the selectivity problem caused by the structural similarity of orthosteric sites among deacetylases. Here, developing a reversed allosteric strategy AlloReverse, we identified a cryptic allosteric site, Pocket Z, which was only induced by the bi-directional allosteric signal triggered upon orthosteric binding of NAD⁺. Based on Pocket Z, we discovered an SIRT6 allosteric inhibitor named JYQ-42. JYQ-42 selectively targets SIRT6 among other histone deacetylases and effectively inhibits SIRT6 deacetylation, with an IC₅₀ of 2.33 μmol/L. JYQ-42 significantly suppresses SIRT6-mediated cancer cell migration and pro-inflammatory cytokine production. JYQ-42, to our knowledge, is the most potent and selective allosteric SIRT6 inhibitor. This study provides a novel strategy for allosteric drug design and will help in the challenging development of therapeutic agents that can selectively bind SIRT6.

Clostridioides difficile is a kind of opportunistic pathogen ubiquitous in human intestinal tracts. It can induce intestinal inflammation by releasing its unique toxins when the body has dysbacteriosis due to various triggers, causing patients to experience a variety of clinical symptoms ranging from simple diarrhea to fatal septic shock. In recent years, the BI/NAP1/027 strain of Clostridioidesdifficile has been detected in stool samples of patients from medical institutions all around China. This kind of strain can produce higher levels of toxins and spores that are more difficult to eradicate. More importantly, the strain will pose tremendous threats and challenges to global public health security once it spreads. In this paper, the epidemiological characteristics, virulence, pathogenic mechanisms, molecular diagnostic techniques and the treatment methods of hypervirulent Clostridioides difficile strain BI/NAP1/027 were summarized based on the existing research results and case reports at home and abroad. The possible future research hotspots and endeavors in the field have also been suggested. This article aimed to make a comprehensive understanding of hypervirulent Clostridioides difficile strain BI/NAP1/027, and to provide a theoretical basis for more in-depth analysis of its pathogenic mechanism and more scientific formulation of its prevention and treatment plans in the future.

Objective:To explore the mediating effect of physical activity on association between sedentary leisure-time and obesity indexes among hypertensive individuals.Methods:After excluding of those with a prior history of heart disease, stroke and cancer, a total of 20 178 hypertensive participants in the China Kadooire Biobank (CKB) study from Wuzhong district of Suzhou city were included. Mediating effect analysis was used to analyze the mediating effect of physical activity (PA) on correlation between sedentary leisure-time and body fat percentage (BFP), waist circumference (WC) and body mass index (BMI).Results:After adjusted for age, gender, smoking status, alcohol consumption, education levels, intake frequencies of meat and intake frequencies of fresh fruit, sedentary leisure-time (SLT) was negatively correlated with PA ( β=-0.246, P<0.001), but positively associated with BFP ( β=0.061, P<0.001), WC ( β=0.087, P<0.001) and BMI ( β=0.071, P<0.001). After including the mediator variable PA, the direct effect of SLT on obesity index was still significant. PA was negatively correlated with BFP, WC and BMI ( β=-0.052, -0.083 and -0.028, respectively, P<0.001). Analysis of mediating effect indicated that the association of SLT with BFP, WC and BMI were partly mediated by PA, the proportion of mediating effect was 20.820%, 23.421% and 9.915%. Stratified by gender, PA had mediating effect on SLT and all obesity indexes in women, while only on SLT and BFP and WC in men. Conclusions:There is a significant mediating effect of PA on correlation between SLT and obesity indexes among hypertensive individuals. Hypertensive patients should increase the level of physical activity and reduce sedentary behavior to achieve a profounder healthy effect.

Objective:To investigate the correlation of serum hepatitis B virus large protein (HBV-LP), HBV-DNA, and Pre S1 antigen (Pre S1-Ag) with HBV replication.Methods:Serum samples were collected from 650 patients with chronic hepatitis B (CHB) who were treated in Beijing Friendship Hospital from March 2017 to March 2019. Serum HBV-LP and Pre S1-Ag were detected by enzyme-linked immunosorbent assay (ELISA). HBV markers (HBV-M) were measured using chemiluminescent microparticle immunoassay (CMIA). Quantitative real-time PCR (qRT-PCR) was used to detect HBV-DNA. The positive detection rates of HBV-DNA, HBV-LP and Pre S1-Ag were calculated and compared, and the correlation of HBV-LP (S/CO value) and hepatitis B surface antigen (HBsAg, log 10 IU/ml) with HBV-DNA(log 10 IU/ml)was analyzed. Results:In the 650 CHB patients, the positive rates of HBV-DNA, HBV-LP and Pre S1-Ag were 65.4% (425/650), 79.2% (515/650) and 43.1% (280/650), respectively ( P<0.01). The positive rates of HBV-DNA and HBV-LP in 243 HBeAg-positive patients were 93.0% (226/243) and 94.6% (230/243), and no significant difference was found between them ( P=0.45). However, there was significant difference between the positive rates of HBV-DNA and HBV-LP in 407 patients negative for HBeAg [48.9% (199/407) vs 70.0% (285/407), P<0.01]. The positive rates of HBV-DNA and HBV-LP in HBsAg-, HBeAg- and HBcAb-positive groups were 92.8% (206/222) and 94.1% (209/222), which showed no significant difference ( P=0.56). In HBsAg-, HBeAb- and HBcAb-positive groups, the positive rates of HBV-DNA and HBV-LP were 45.4% (124/273) and 69.9% (191/273) ( P<0.01). The detection rate of HBeAg was lower than that of HBV-LP significantly in both HBV-DNA-positive and HBV-DNA-negative groups ( P<0.01). With the increasing of HBV-DNA load, the S/CO value and the positive rate of HBV-LP increased significantly ( P<0.05). Conclusions:HBV-LP had a good correlation with HBV-DNA load as compared with Pre S1-Ag, HBeAg and HBsAg. HBV-LP in combination with HBV-M might be used as predictive markers that could efficiently reflect the status of HBV replication.

Objective:To evaluate the association betweew family history of diabetes and incident diabetes of adults.Methods:A total of 49 266 participants in the China Kadoorie Biobank (CKB) study from Wuzhong district of Suzhou city were included in the analysis, after the exclusion of those with heart disease, stroke, cancer and diabetes at baseline survey. The person-year of follow-up was calculated from the date on completion of baseline survey to the date on any firstly-occurred event, i.e., diabetes incidence, death, loss of follow-up, or December 31, 2013. Cox regression model was used to estimate the hazards ratios of the association between family history of diabetes and incident diabetes.Results:During 348 677 person-years of the follow-up (median 7.08 years), a total of 423 men and 791 women were diagnosed as having diabetes. Compared to those without diabetic family history, participants with family history of diabetes showed a higher risk of diabetes, with a HR (95% CI) of 1.90 (1.57-2.29), and the risk increased with the number of relatives suffering from diabetes ( P for trend<0.05). The family history of maternal type, sibling type, and sibling and parental type had a statistically significant association with the risk of diabetes. The adjusted HR (95% CI) was 2.03 (1.45-2.77), 2.07 (1.56-2.68) and 2.39 (1.14-4.34), respectively. Modification effects of tobacco smoking, alcohol drinking, body mass index and physical activity on the association between diabetic family history and risk of diabetes were not observed in the study ( P for interaction>0.05). Conclusions:Diabetic family history is associated with the increased incident diabetes, and the risk increased with the number of relatives suffering from diabetes.