OBJECTIVES: To detect prfA and hly toxin genes of Listeria monocytogenes using polymerase chain reaction (PCR) and colloidal gold technology. METHODS: L. monocytogenes DNA was extracted by boiling method. With prfA and hly of L. monocytogenes as the target genes, the 5' ends of upstream and downstream primers of prfA gene were labeled with 6-FAM and biotin, and the 5' ends of upstream and downstream primers of hly gene were labeled with digoxin and biotin, respectively, to establish the toxin gene detection method. Using cloning transformation, sequencing analysis, cloning of positive control products, the detection kid was developed and its specificity, sensitivity, reproducibility and stability were tested, followed by verification with sample testing. RESULTS: The concentration of L. monocytogenes DNA extracted by boiling method was 148.81±0.97 ng/μL, and the A₂₆₀/A₂₈₀ ratio ranged from 1.8 to 2.0. The PCR products showed a 100% homology with the gene sequences in GenBank database after cloning, transformation and sequencing. The colloidal gold strip yielded positive results only for L. monocytogenes samples without cross-reactions with Staphylococcus aureus, Escherichia coli or Bacillus cereus, and its minimum detection limit was 10^-2 ng/μL, demonstrating a 10-fold greater sensitivity of the test than agarose gel electrophoresis. The test also showed good reproducibility of the results when performed by different operators with good stability of the test strips after storage for 6 to 12 months. The test results showed that this kit could accurately and quickly detect L.monocytogenes in the test samples. CONCLUSIONS The detection kit developed in this study can simultaneously detect prfA and hly toxin genes of L. monocytogenes with good specificity, sensitivity, reproducibility and stability for use in food safety inspection.
Listeria monocytogenes/isolation & purification* ; Gold Colloid ; Bacterial Toxins/genetics* ; Polymerase Chain Reaction/methods* ; Hemolysin Proteins/genetics* ; Bacterial Proteins/genetics* ; DNA, Bacterial/genetics* ; Food Microbiology ; Heat-Shock Proteins

AIM:To investigate the preventive and therapeutic effects of sesamin(SES)on fatty liver disease in rats with hypertension combined with dyslipidemia,and to explore the potential mecha-nisms based on mRNA-seq.METHODS:Spontane-ously hypertensive rats(SHRs)were fed a high-fat,high-cholesterol diet to establish a rat model of hy-pertension combined with dyslipidemia,and then treated with SES for 16 weeks continuously.The ex-periment was divided into four groups:WKY,SHR,Model,and Model+SES(160 mg·kg-1·d-1).Blood pressure was measured using the tail-cuff method.Body weight was monitored,and body mass index was calculated.Liver morphology was detected by ultrasound,and liver thickness was measured.Liver wet weight was weighed,and liver index was calcu-lated.Liver volume was detected by the water dis-placement method.Serum triglycerides(TG),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),alanine aminotransferase(ALT),aspartate amino-transferase(AST),and total bile acids(TBA)were de-tected by ELISA.Liver sequencing analysis was per-formed using mRNA-seq.Liver histomorphological changes were observed by HE staining.The degree of hepatic steatosis was observed by Oil Red O stain-ing,and the degree of hepatic fibrosis was observed by MASSON staining.The mRNA expression of Al-dh1a7,Nnmt,Irs2,Pltp,and Scd was detected by q-PCR.The protein expression of Scd,Nnmt,AMPK,p-AMPK,PPARα,and PPARγ was detected by Western blotting.RESULTS:After 16 weeks of continuous SES administration to rats with hypertension combined with dyslipidemia,blood pressure was significantly reduced(P＜0.01),and body weight was decreased.Serum TG,TC,and LDL-C levels were decreased,while HDL-C levels were increased.Serum ALT and AST levels were decreased.Liver weight,organ in-dex,liver thickness,and liver volume were de-creased.The degree of hepatic steatosis and hepat-ic fibrosis was improved.A total of 545 differentially expressed mRNAs were identified in the livers of rats in each group,of which 278 were upregulated and 267 were downregulated.Among the 27 com-monly differentially expressed mRNAs,five mRNAs related to lipid metabolism were screened,namely Aldh1a7,Nnmt,Irs2,Pltp,and Scd.KEGG enrich-ment analysis showed that the enriched pathways were AMPK and PPAR.Further validation revealed that in the SES-treated group,the mRNA expression of Scd in the liver was decreased,while the mRNA expression of Nnmt was increased.The protein ex-pression of Scd was decreased,while the protein ex-pression of Nnmt,AMPK,p-AMPK,PPARα,and PPARγ was increased.CONCLUSION:SES has preven-tive and therapeutic effects on fatty liver disease in rats with hypertension combined with dyslipidemia,and its mechanism of action may be related to the reduction of Scd expression levels in the liver and the increase in the expression of Nnmt,AMPK,p-AMPK,PPARα,and PPARγ.

Objective To investigate the association of cerebral white matter lesions(WMLs)with systolic and diastolic blood pressure.Methods Patients admitted to our department from January 2023 to December 2023 were prospectively recruited for this study.The Fazekas method was used to grade the severity of the periventricular WMLs(P-WMLs)and deep WMLs(D-WMLs).Multivariate logistic regression analyses were performed to examine the association of systolic and diastolic blood pressure with WMLs.Results A total of 966 eligible participants were enrolled in this study.The mean age was 65.96±11.35 years and 487 participants(50.41%)were male.The results indicated that the more severe the P-WMLs and D-WMLs,the higher the systolic blood pressure was[P-WMLs:0:(134.41±19.86)mmHg,1:(136.82±20.47)mmHg,2:(144.52±21.64)mmHg,3:(147.80±20.7)mmHg;D-WMLs:0:(137.49±20.58)mmHg,1:(139.17±21.33)mmHg,2:(144.39±21.20)mmHg,3:(147.50±21.73)mmHg],but not diastolic blood pressure.Multivariate logistic regression analysis showed that an elevated systolic level(P-WMLs:OR=1.02,95%CI:0.009-0.021;D-WMLs:OR=1.01,95%CI:0.005-0.016)was associated with an increased risk of more severe of P-WMLs and deep D-WMLs.No significant association was observed between diastolic blood pressure and WMLs,whether for P-WMLs or D-WMLs.Conclusion The more severe P-WMLs and D-WMLs were,the higher the systolic blood pressure was.Elevated systolic blood pressure was an independent risk factors for more severe of P-WMLs and D-WMLs,but not diastolic blood pressure.

Type 2 inflammation（T2 inflammation）is an immune response mediated by Th2 cells，eosinophils，type 2 innate lymphocytes，and other cells. Its pathological characteristics are manifested by the abnormally high expression of type 2 cytokines such as IL-4，IL-5，and IL-13，and it widely involves allergic diseases including asthma，allergic rhinitis，and atopic dermatitis. Ginsenosides are the core active ingredients of ginseng and the key substances for ginseng to exert its pharmacological effects. It has anti-inflammatory and immunomodulatory effects. This article reviews the mechanism of action，experimental research progress，and clinical application prospects of ginsenosides in T2 inflammation，explores the therapeutic potential and clinical challenges of ginsenosides，and proposes future research directions.

Insufficient future liver remnant volume remains a critical limitation for single-stage resection in patients with hepatic malignancies. The techniques for promoting future liver remnant hypertrophy to realize two-stage hepatectomy include portal vein embolization， associating liver partition and portal vein ligation for staged hepatectomy， and portal vein ligation. In recent years， the application of auxiliary liver transplantation has further facilitated two-stage total hepatectomy. This article systematically reviews the clinical applications of these techniques and analyzes their advantages and limitations， so as to provide a reference for optimizing clinical decision-making.

Objective:To discuss the effect of quorum sensing-related gene expression on biofilm formation and drug resistance in clinically multidrug-resistant Pseudomonas aeruginosa,and to clarify the mechanism of enhacing drug resistance.Methods:A total of 77 strains of Pseudomonas aeruginosa were collected.Based on drug resistance,the strains were divided into multidrug-resistant group and sensitive group.The optimal biofilm formation conditions were determined using the microtiter plate method;biofilm formations of the stains in both groups was observed under an optical microscope;crystal violet staining was used to semiquantitatively detect biofilm formation ability of P.aeruginosa in both groups;microbroth dilution method was used to determine the minimal inhibitory concentration(MIC)values of the quorum sensing inhibitor(C-30)against Pseudomonas aeruginosa in both groups;RNA was extracted from two groups using a commercial kit,while RNA from planktonic state and biofilm state of multidrug-resistant strains was extracted using modified TRIzol method;real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the mRNA expression levels of quorum sensing-related genes(lasR/I,RhlR/I,PqsR/A)of the stains in multidrug-resistant group and sensitive group,as well as before and after adding the quorum sensing inhibitor C-30.Results:Among 77 strains of Pseudomonas aeruginosa,56 were multidrug-resistant(multidrug-resistant group)and 21 were fully sensitive(sensitive group).Optimal biofilm formation occurred at a bacterial concentration of 1.5×108 CFU·mL-1 with 48 h incubation.The biofilm positivity rate was 91%,with strongly positive,moderately positive,weakly positive,and negative biofilms accounting for 16%,34%,41%,and 9%,respectively.The biofilm positivity rate in multidrug-resistant strains was 96%,and biofilm formation ability in multidrug-resistant group was higher than that in sensitive group(P<0.05).When the concentration of C-30 was 8 mg·L-1 the biofilm formation in most Pseudomonas aeruginosa was inhibited,with enhanced suppression at higher concentrations.The absorbtion(A)value of both planktonic-state and biofilm-state RNA ranged from 1.8 to 2.0.The RT-qPCR results showed that compared with planktonic state,the expression levels of lasR/I,RhlR/I,and PqsR/A mRNA of the stains in biofilm state were significantly increased(P<0.01).Compared with non-inhibitor group,the expression levels of lasR/I,RhlR/I,and PqsR/A mRNA in biofilm state of inhibitor-treated group were significantly decreased(P<0.01).Conclusion:High expression of quorum sensing-related genes in multidrug-resistant P.aeruginosa promotes biofilm formation,thereby enhancing drug resistance.

Objective:To establish a rapid detection method for pathogenic microorganisms by combining loop-mediated isothermal amplification(LAMP)and clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 12a(Cas12a)(CRISPR-Cas12a)system,and to evaluate its efficacy for detecting the thermolabile hemolysin(tlh)gene of Vibrio parahaemolyticus(Vp).Methods:Using the tlh gene of Vp as the target gene,LAMP primers and CRISPR RNA(crRNA)were designed to construct and optimize the optimal concentration ratio of each component in the LAMP-CRISPR detection system.Bacillus cereus,Staphylococcus aureus,and Escherichia coli were used as control groups,and the specificity,sensitivity,reproducibility and positive conformity rate were verified to establish a rapid LAMP-CRISPR/Cas12a method for detecting the tlh gene of Vp.Results:The method specifically detected Vp,while Bacillus cereus,Staphylococcus aureus,and Escherichia coli yielded negative results.The DNA extraction concentration of Vp was 190.67 mg·L-1 with an A(260)/(A280)ratio of 1.84.Under the reaction conditions of 37℃ with 80 cycles for 40 min using quantitative PCR(qPCR)method,when the concentrations of Cas12a protein and crRNA in the LAMP-CRISPR/Cas12a system were 50 nmol·L-1,the visual brightness and relative fluorescence intensity peaks were high.The sensitivity of LAMP CRISPR/Cas12a for detecting Vp DNA concentration could reach 10-6 mg·L-1.The reproducibility test results showed that different experimenters had consistent results in different experimental environments and times.Conclusion:The established LAMP-CRISPR/Cas12a method can rapidly detect the tlh gene of Vp with high sensitivity and specificity,and can achieve short-term visual detection in the field.

Objective:To investigate the difference in intracranial infection rate between long-tunneled external ventricular drainage(LTEVD)and conventional external ventricular drainage(EVD),as well as the risk factors for intracranial infection.Methods:A retro-spective analysis was performed for the clinical data of 45 patients who were admitted to Department of Neurology Center,The Third Affiliated Hospital of Chongqing Medical University,from January 2020 to December 2022 and underwent EVD,among whom 13 patients underwent LTEVD(LTEVD group)and 32 patients underwent conventional EVD(EVD group).Related data were recorded for both groups,including general information,postoperative catheter-related complications,and postoperative management,to investi-gate the effect on reducing the rate of intracranial infection.According to the presence or absence of intracranial infection after surgery,the patients were divided into the infection group with 10 patients and non-infection group with 35 patients,and related clini-cal data were analyzed to investigate the risk factors for intracranial infection.Results:The LTEVD group had a significantly lower secondary infection rate of catheterization days than the EVD group[2.40‰(1/417)vs.27.19‰(9/331),P=0.009].The duration of catheterization was 14-85 days[27.00(22.50,36.50)days]in the LTEVD group and 8-22 days[9.00(8.00,11.50)days]in the EVD group,suggesting that the LTEVD group had a significantly longer duration of catheterization than the EVD group(P=0.000).The multivariate logistic regression analysis showed that the times of cerebrospinal fluid sampling was an independent risk factor for post-operative intracranial infection in patients undergoing EVD,and the use of LTEVD was a protective factor against intracranial infection after EVD.Conclusion:Compared with conventional EVD,LTEVD can safely prolong the duration of catheterization and reduce the rate of postoperative intracranial infection in patients undergoing EVD.The use of LTEVD procedure and the reduction in the times of cerebrospinal fluid sampling can reduce the risk of postoperative in-tracranial infection.

Objective:This study aims to investigate the differences between two groups of patients treated with nucleos（t）ide analogues（NAs）：those with undetectable HBV DNA by ultrasensitive testing and those with HBV DNA below the quantification limit. The findings will provide a basis for the clinical interpretation and rational use of ultrasensitive HBV DNA results.Methods:This cross-sectional study included patients with chronic HBV infection who were treated with NAs between May 2023 and December 2023 at the outpatient clinic and inpatient department of the Hepatology Department，The Second Hospital of Shandong University. All patients had ultrasensitive HBV DNA results that were either undetectable or less than 20 IU/ml. The group with undetectable ultrasensitive HBV DNA was defined as the target not detected（TND）group，while the group with HBV DNA levels below 20 IU/ml was defined as the limit of quantitation（LOQ）group. Data on patients' sex，age，type of NAs used，routine blood tests，liver and kidney function，quantitative hepatitis B serology，ultrasensitive HBV DNA，HBV pregenomic RNA（pgRNA），abdominal ultrasound，CT or MRI imaging were collected. Differences between the two groups in terms of demographic data and HBV markers were analyzed.Results:A total of 827 patients were included in the study，with 536 patients in the TND group and 291 in the LOQ group. Compared with the TND group，the LOQ group had a younger age（ P<0.001），and higher level of ALT，AST，HBeAg positive rate，HBsAg，and HBV pgRNA（all P<0.001）. Subgroup analyses stratified by HBeAg status，cirrhosis status，and sex showed that the LOQ group had significantly higher levels of HBsAg and HBV pgRNA compared to the TND group in all subgroups（all P<0.05）. Conclusion:The LOQ group had significantly higher levels of HBsAg and HBV pgRNA compared to the TND group.

Objective:To investigate effect of testosterone on polarization of M1 macrophages induced by lipopolysaccharide(LPS).Methods:CCK-8 method was used to detect effects of LPS and testosterone on RAW 264.7 cell viability.Morphological changes of cells were observed by optical microscope.mRNA expression levels of M1-type polarizing genes TNF-α,IL-1β and IL-6 in macro-phages were detected by qRT-PCR.Expression levels of M1-polarizing protein TNF-α and CD206 in macrophages were detected by immunofluorescence and Western blot.Secretion of inflammatory cytokines was detected by ELISA.Results:Testosterone could decrease mRNA expressions of TNF-α,IL-1β and IL-6 mRNA and protein expression of TNF-α.Finally,testosterone could decrease secretion of inflammation-related factors.Conclusion:Testosterone can inhibit LPS-induced transformation of macrophages to M1 polarization phenotype.