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

This research study focuses on addressing the limitations of current neuropathic pain (NP) treatments by developing a novel dual-target modulator, E0199, targeting both Na_V1.7, Na_V1.8, and Na_V1.9 and K_V7 channels, a crucial regulator in controlling NP symptoms. The objective of the study was to synthesize a compound capable of modulating these channels to alleviate NP. Through an experimental design involving both in vitro and in vivo methods, E0199 was tested for its efficacy on ion channels and its therapeutic potential in a chronic constriction injury (CCI) mouse model. The results demonstrated that E0199 significantly inhibited Na_V1.7, Na_V1.8, and Na_V1.9 channels with a particularly low half maximal inhibitory concentration (IC₅₀) for Na_V1.9 by promoting sodium channel inactivation, and also effectively increased K_V7.2/7.3, K_V7.2, and K_V7.5 channels, excluding K_V7.1 by promoting potassium channel activation. This dual action significantly reduced the excitability of dorsal root ganglion neurons and alleviated pain hypersensitivity in mice at low doses, indicating a potent analgesic effect without affecting heart and skeletal muscle ion channels critically. The safety of E0199 was supported by neurobehavioral evaluations. Conclusively, E0199 represents a ground-breaking approach in NP treatment, showcasing the potential of dual-target small-molecule compounds in providing a more effective and safe therapeutic option for NP. This study introduces a promising direction for the future development of NP therapeutics.

Objective: To prepare hollow mesoporous silicon nanoparticles ( HMSNs) loaded with allicin—diallyl trisulfide (DATS) , and to study their feasibility as a therapeutic agent for ischemic injury of lower limbs . Methods: HMSNs were synthesized by selective etching , and their microstructure was observed by scanning and transmis- sion electron microscopy. Their physical and chemical properties were analyzed by X-ray diffraction and dynamic light scattering (DLS) . Their biological safety was tested by erythrocyte hemolysis and cytotoxicity experiments . DATS was loaded into HMSNs by adsorption to obtain DATS sustained release nanoparticles (DATS-HMSNs) , and the cumulative release curve of DATS was calculated and produced by ultraviolet spectrophotometry. C57BL/6 mice were randomly divided into four groups (sham operation group , normal saline group , DATS group , and DATS-HM- SNs group) . Lower limb ischemia models were made by femoral artery ligation and resection . The exercise ability and the contents of tumor necrosis factor alpha (TNF-α ) , interleukin-6 (IL-6) , monocyte chemoattractant protein- 1 (MCP-1) , reactive oxygen species (ROS) , platelet-endothelial cell adhesion molecule (CD31) , alpha smooth muscle actin ( α-SMA) , basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) in muscles of mice in each group before and after limb ischemia were tested . Results : Scanning and transmission e- lectron microscope observation showed that the prepared HMSNs were hollow , spherical and uniform in particle size . DLS results showed that the particle size was (226. 5 ± 11 . 8) nm. The results of red blood cell hemolysis test and cytotoxicity test showed that HMSNs had good biocompatibility. The maximum drug loading rate of HMSNs on DATS was 27. 89% , the cumulative release rate of DATS in 7 days was about 80. 12% , and could reach 97. 27% in 21 days . Compared with the control group , after DATS-HMSNs were applied to mice with lower limb ischemia , immunohistochemical staining showed that the levels of CD31 , α-SMA , bFGF and VEGF increased ( P < 0. 05) . Elisa test showed that the levels of TNF-α , IL-6 , MCP-1 and ROS decreased (P < 0. 05) , and the exercise ability of mice recovered satisfactorily after ischemia. Conclusion DATS-HMSNs can release DATS slowly and continu- ously , providing protection against ischemic injury of lower limbs .

Objective:To establish a method of dual nueleic acid test strips for rapid detection of Bacillus cereus cytK and nhe toxin genes based on polymerase chain reaction(PCR)and colloidal gold technique,and to evaluate its specificity,sensitivity,repeatability and stability.Methods:Bacillus cereus DNA was extracted by boiling method.Specific primers were designed with Bacillus cereus cytK and nhe as the target genes.Clonal transformation was used to identify the PCR products.The optimal labeling amounts of colloidal gold-labeled streptavidin,quality control line(C line),cytK detection line(T1)and nhe detection line(T2)were determined.The nucleic acid test strips were assembled and its specificity,sensitivity,reproducibility and stability were evaluated.Results:The DNA concentration of Bacillus cereus was 248 mg·L-1,and the purities were 1.8-2.0.After cloning and plasmid sequencing,the similarities between the PCR products and the sequences of cytK and nhe registered in the GenBank database were 100％.Under the condition of pH 7.0,the optimal amount of streptavidin labeling per 200 μL of colloidal gold solution was 6.0 μL;the optimal marking amount was 2.00 g·L-1 for the quality control line(C line),0.550 g·L-1 for cytK gene detection line(T1)and 0.2 g·L-1 for nhe gene detection line(T2).In the specificity test,positive result on the test strips was seen only for Bacillus cereus,and no cross-reactivity was observed for Staphylococcus aureus,Escherichia coli,Pseudomonas aeruginosa and Bacillus subtilis,which were consistent with the electrophoresis results.Sensitivity assay showed that even when DNA concentration was reduced to 10-2 mg·L-1,three bands(C line,T1 line and T2 line)could be observed,and the detection limit of the test strip was one-tenth of agarose gel electrophoresis(10-1 mg·L-1).The nucleic acid test strips were verified by different operators in different laboratories,and the results were consistent.The stability of the test strips was verified at the 6th,9th and 12th months,and the results showed good stability.Conclusion:The dual nucleic acid test strip method established in this study can simutaneously detect the cytK and nhe toxin genes of Bacillus cereus with high sensitivity and specificity,achieving short-term visual detection.

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 infection status and changing trend of hepatitis C virus(HCV)infection in hospitalized patients in medical institutions,and provide reference for formulating HCV infection prevention and control strategies.Methods HCV infection surveillance results from cross-sectional survey data reported to China Healthcare-associated Infection(HAI)Surveillance System in 2020 were summarized and analyzed,HCV positive was serum anti-HCV positive or HCV RNA positive,survey result was compared with the survey results from 2003.Results In 2020,1 071 368 inpatients in 1 573 hospitals were surveyed,738 535 of whom underwent HCV test,4 014 patients were infected with HCV,with a detection rate of 68.93％and a HCV positive rate of 0.54％.The positive rate of HCV in male and female patients were 0.60％and 0.48％,respectively,with a statistically sig-nificant difference(x2=47.18,P＜0.001).The HCV positive rate in the 50-＜60 age group was the highest(0.76％),followed by the 40-＜50 age group(0.71％).Difference among all age groups was statistically signifi-cant(x2=696.74,P＜0.001).In 2003,91 113 inpatients were surveyed.35 145 of whom underwent HCV test,resulting in a detection rate of 38.57％;775 patients were infected with HCV,with a positive rate of 2.21％.In 2020,HCV positive rates in hospitals of different scales were 0.46％-0.63％,with the highest in hospital with bed numbers ranging 600-899.Patients'HCV positive rates in hospitals of different scales was statistically signifi-cant(X2=35.34,P＜0.001).In 2020,12 provinces/municipalities had over 10 000 patients underwent HCV-rela-ted test,and HCV positive rates ranged 0.19％-0.81％,with the highest rate from Hainan Province.HCV posi-tive rates in different departments were 0.06％-0.82％,with the lowest positive rate in the department of pedia-trics and the highest in the department of internal medicine.In 2003 and 2020,HCV positive rates in the depart-ment of infectious diseases were the highest,being 7.95％and 3.48％,respectively.Followed by departments of orthopedics(7.72％),gastroenterology(3.77％),nephrology(3.57％)and general intensive care unit(ICU,3.10％)in 2003,as well as departments of gastroenterology(1.35％),nephrology(1.18％),endocrinology(0.91％),and general intensive care unit(ICU,0.79％)in 2020.Conclusion Compared with 2003,HCV positive rate decreased significantly in 2020.HCV infected patients were mainly from the department of infectious diseases,followed by departments of gastroenterology,nephrology and general ICU.HCV infection positive rate varies with gender,age,and region.

AIM:This study aims to investigate the effects and mechanisms of silent information regulator 6(SIRT6)on carbon tetrachloride(CCl4)-induced liver fibrosis in mice,as well as the expression changes in the down-stream pathways of hepatic stellate cells after SIRT6 silencing.METHODS:Thirty male C57BL/6J mice were randomly divided into a normal control group(n=6)and a model group(modeling at 2,4,8,12 weeks,n=24).A liver fibrosis model in mice was prepared by intraperitoneal injection of CCl4 twice a week for 12 weeks.Serum alanine aminotransfer-ase(ALT)and aspartate aminotransferase(AST)levels were measured to assess liver injury.Hematoxylin-eosin(HE)and Masson staining were used to observe the pathological changes in mouse liver tissues.Immunohistochemical staining was conducted to detect the expression of α-smooth muscle actin(α-SMA)in the liver,Western blot analysis was used to measure the expression of liver α-SMA,SIRT6,acetyl histone H3 at Lys9(H3K9ac),acetyl histone H3 at Lys56(H3K56ac),interleukin-1β(IL-1β),and IL-18 proteins.Hepatic stellate cells-T6(HSC-T6)underwent SIRT6 gene si-lencing,divided into NC siRNA group and SIRT6 siRNA group,with Western blot performed to detect the expression of SIRT6,H3K9ac,and H3K56ac proteins.RESULTS:Compared with the normal control group,the serum ALT and AST levels in the model group were significantly increased(P<0.05);HE and Masson staining results showed that the patho-logical changes in the liver of the model group worsened over time,with an increase in collagen fiber deposition.Both im-munohistochemistry and Western blot showed that the expression of liver α-SMA significantly increased at 8 and 12 weeks in the model group(P<0.05).Western blot results showed that the expression of SIRT6 protein in the liver of all model group mice was lower than that in the normal control group(P<0.05),and decreased gradually with the progression of liv-er fibrosis;also,the expression levels of H3K9ac,H3K56ac,IL-1β,and IL-18 in the liver of the model group mice were significantly elevated at 8 and 12 weeks(P<0.05);after SIRT6 silencing,compared with the NC siRNA group,the levels of H3K9ac and H3K56ac in the SIRT6 siRNA group significantly increased(P<0.05).CONCLUSION:The deficiency of SIRT6,by abnormally increasing H3K9ac and H3K56ac,raises the expression of IL-1β and IL-18,intensifying the in-flammatory response and promoting the progression of liver fibrosis,indicating that the aberrant expression of SIRT6 is in-volved in the development of liver fibrosis.

Objective To investigate the conversion rate, organ procurement rate and influencing factors of organ donation in a single center from Fujian province. Methods Baseline data of 182 potential organ donors of Fujian Medical University Union Hospital from November 2018 to June 2021 were retrospectively analyzed. The conversion rate of organ donation, baseline data of successful organ donors and the causes of failure of organ donors were identified. The organ procurement rate and the influencing factors of the number of organ donations were analyzed. Results Among 182 potential organ donors, 46 cases were successful organ donors with a conversion rate of 25.3%. In addition, 136 cases failed to donate organ. The main causes included disagreement from family members (58.1%), insufficient evaluation time (24.3%) and ineligible for donation criteria (17.6%). A total of 212 large organs and tissues were donated by 46 organ donors, including 88 kidneys, 42 livers, 15 lungs, 19 hearts and 48 corneas, with 4.6 large organs and tissues, and 3.6 large organs for each donor. Age, sex, native place, organ donation area and blood type were the influencing factors of the number of large organ donations. Organ donation area was the influencing factor of the number of tissue donations. Conclusions The conversion rate of organ donation is relatively low in a single center from Fujian province. Disagreement from family members is the main cause. Suitable potential organ donors should be selected for organ donation to improve the conversion rate and organ procurement rate of organ donation.

Objective:To evaluate the cosmetic outcomes of non-eyebag associated tear trough deformities (TTDs) using the transconjunctival lower eyelid blepharoplasty with release of the tear trough ligament (TTL) and orbital septum fat reposition.Methods:Non-eyebag associated TTDs patients who received the transconjunctival lower eyelid blepharoplasty with release of TTL and with reposition of the orbital septum fat flap internally fixed to the premaxillary-prezygomatic space were retrospectively reviewed at the Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from September 2019 to April 2020. The "Hirmand" types of TTDs were classified preoperatively based on the digital photography. Tear trough rating scale (TTRS) introduced by Sadick was used to assess TTDs before and after surgeries based on depth of the trough, hyperpigmentation, prolapse of nasal fat pads/pockets, and lower eyelid skin rhytidosis. "Barton" grading system was used to evaluate demarcation of orbit-cheek junction area preoperatively and postoperatively. Ultimate surgical outcomes of TTDs were assessed by TTRS, Barton and patient self-assessment scores. Patients were followed up postoperatively and the complications were filed. Matched samples t-test (SPSS 20.0 software) was used for statistical analysis to compare TTRS scores pre- and post-surgery. Results:A total of 79 patients with bilateral TTDs were enrolled, including 24 men and 55 women. Their age ranged from 19 to 38 years old (average, 25.7 years old). Edema or congestion in conjunctiva presented in all patients within 3 days after surgery. Slight eyelid skin ecchymosis, lower eyelid edema or asymmetry was presented in 11 cases, and they all recovered in 1-2 weeks. No other complications occurred. The follow-up period ranged from 5 to 13 months (average, 8.5 months). TTRS scores between pre- and post-surgeries demonstrated no significant difference in Hirmand type Ⅰ ( P>0.05), but presenting significant difference both in Hirmand type Ⅱ and Hirmand type Ⅲ ( P<0.01). All cases (33) in Hirmand type Ⅰ graded as Barton 1 pre-surgery were improved to grade 0 post-surgery. There were 35 cases categorized as Hirmand type Ⅱ. Among them, 7 (20%), 25 (71.4%) and 3 cases (8.6%) were graded as Barton 1, 2 and 3 pre-surgery, respectively. Postoperatively, they were improved to Barton 0 (30 cases, 85.7%) and 1 (5 cases, 14.3%), accordingly. There were 11 cases categorized as Hirmand type Ⅲ, which included 6 cases graded as Barton 2 and 5 cases graded as Barton 3. After surgery, they were improved to Barton 0 (2 cases, 18.2%), Barton 1 (5 cases, 45.5%) and Barton 2(4 cases, 26.3%). As to overall cosmetic satisfaction, 78.5% (62/79), 17.7% (14/79) and 3.8% (3/79) were self-assessed as good, moderate and poor by the patients, respectively. Conclusions:Transconjunctival lower eyelid blepharoplasty with release of tear trough ligament and fat reposition can achieve satisfactory lower eyelid rejuvenation in tear trough deformities not associated with eyebags.