Objective:To analyze the contamination characteristics and pathogenic potential of Listeria monocytogenes (LM) in pre-packaged and refrigerated ready-to-eat cooked meat products in Chengdu City. Methods:From September 2022 to May 2023, pre-packaged and refrigerated ready-to-eat cooked meat products were collected from six districts and counties in Chengdu City. Qualitative and quantitative determination of LM was performed on these samples. Whole genome sequencing was carried out on the isolated strains. Different ST strains were selected for cell adhesion and invasion experiments. The results were expressed as adhesion rate and invasion rate. One-way ANOVA was used for comparison between groups, and the Dunnett t-test was used for pairwise comparison. Results:A total of 145 samples were collected, and LM was detected and isolated in 29 samples. The total detection rate was 20.00%, and the detection rate of braised pork was the highest (68.18%). The contamination level of LM in 9 samples (31.03%) was greater than 100.00 MPN/g. The 29 strains of Listeria monocytogenes belonged to 7 STs, including ST 3 (27.59%), ST 8 (17.24%) and ST 87 (13.79%). The strain of ST 87 carried Listeria pathogenicity islands 4 (LIPI-4), which was a highly virulent strain. The medium and high virulence strains accounted for 79.31%. Some moderately virulent and highly virulent strains of ST 8 and ST 87 were closely related to clinical patient strains. Some LM isolates of the same ST type had little SNP differences (1-6) in the same manufacturer at different stages. In vitro cell experiments showed that the highly virulent strain ST 87 had the strongest adhesion and invasion ability towards Caco-2 cells. Conclusion:The pre-packaged and refrigerated cooked meat products have a high contamination rate. Some samples have high contamination levels and carry medium and high virulence strains, posing potential health risks to human beings. LM residues continue to persist in some manufacturers′ production and processing stages.

Objective:To analyze the contamination characteristics and pathogenic potential of Listeria monocytogenes (LM) in pre-packaged and refrigerated ready-to-eat cooked meat products in Chengdu City. Methods:From September 2022 to May 2023, pre-packaged and refrigerated ready-to-eat cooked meat products were collected from six districts and counties in Chengdu City. Qualitative and quantitative determination of LM was performed on these samples. Whole genome sequencing was carried out on the isolated strains. Different ST strains were selected for cell adhesion and invasion experiments. The results were expressed as adhesion rate and invasion rate. One-way ANOVA was used for comparison between groups, and the Dunnett t-test was used for pairwise comparison. Results:A total of 145 samples were collected, and LM was detected and isolated in 29 samples. The total detection rate was 20.00%, and the detection rate of braised pork was the highest (68.18%). The contamination level of LM in 9 samples (31.03%) was greater than 100.00 MPN/g. The 29 strains of Listeria monocytogenes belonged to 7 STs, including ST 3 (27.59%), ST 8 (17.24%) and ST 87 (13.79%). The strain of ST 87 carried Listeria pathogenicity islands 4 (LIPI-4), which was a highly virulent strain. The medium and high virulence strains accounted for 79.31%. Some moderately virulent and highly virulent strains of ST 8 and ST 87 were closely related to clinical patient strains. Some LM isolates of the same ST type had little SNP differences (1-6) in the same manufacturer at different stages. In vitro cell experiments showed that the highly virulent strain ST 87 had the strongest adhesion and invasion ability towards Caco-2 cells. Conclusion:The pre-packaged and refrigerated cooked meat products have a high contamination rate. Some samples have high contamination levels and carry medium and high virulence strains, posing potential health risks to human beings. LM residues continue to persist in some manufacturers′ production and processing stages.

BACKGROUND:Pulsed electromagnetic fields,as an important physical therapy,are exactly effective in the treatment of osteoarthritis,but the mechanism has not been fully clarified. OBJECTIVE:To observe the effect of pulsed electromagnetic field on the degeneration of knee joint cartilage in aged rats. METHODS:Eight 6-month-old Sprague-Dawley rats were selected as the young group and were subjected to normal diet with no treatment.Sixteen 22-month-old Sprague-Dawley rats were randomly divided into old group(n=8)and pulsed electromagnetic field group(n=8).The rats in the pulsed electromagnetic field group were subjected to a pulsed electromagnetic field intervention,once a day,5 days per week for continuous 8 weeks.The rats in the old group were given no treatment.All rats were anesthetized and executed after 8 weeks for the detection of relevant indexes. RESULTS AND CONCLUSION:Compared with the young group,serum type Ⅱ collagen C-terminal peptide level was increased in the old group(P<0.05);compared with the old group,serum type Ⅱ collagen C-terminal peptide level was decreased in the pulsed electromagnetic field group(P<0.05).Micro-CT showed that the bone volume fraction,bone mineral density,and number of bone trabeculae decreased(P<0.05)and the trabecular separation increased(P<0.05)in the tibia of rats in the aged group compared with the young group;and the bone volume fraction,bone density,and number of trabeculae increased(P<0.05)and the trabecular separation decreased(P<0.05)in the tibia of rats in the pulsed electromagnetic field group compared with the aged group.The tibial plateau Safranin O-fast green staining showed that the articular cartilage structure of rats in the aged group was disorganized,and the number of chondrocytes was obviously reduced,and the tidal line could not be distinguished.The above results were improved in the pulsed electromagnetic field group.RT-qPCR and western blot assay showed that the mRNA and protein expression levels of matrix metalloproteinase 1,matrix metalloproteinase 13,P53 and P21 in the articular cartilage and subchondral bone of rats were elevated in the aged group compared with the young group(P<0.05)and decreased in the pulsed electromagnetic field group compared with the old group(P<0.05).To conclude,pulsed electromagnetic fields may improve osteoarthritis in aged rats by inhibiting chondrocyte senescence,alleviating articular cartilage degradation and inhibiting subchondral bone osteoporosis through suppressing the expression of P53/P21.

Objective To investigate the effect of artesunate(ART)on hypoxia/reoxygenation(H/R)-induced injury of human renal proximal tubular HK-2 cells by regulating the high mobility group protein B1(HMGB1)-receptor of advanced glycation endproduct(RAGE)signaling pathway.Methods HK-2 cells cultured in vitro were stochastically separated into control group,model group,L-ART group(4 μg/ml ART),H-ART group(16 μg/ml ART),H-ART+pcDNA NC group(16 μg/ml ART+transfected pcDNA NC plasmid),and H-ART+pcDNA-HMGB1 group(16 μg/ml ART+transfected pcDNA-HMGB1 plasmid).HK-2 cells in the control group were cultured normally,while the cells in the other groups were induced with hypoxia/reoxygenation(H/R).MTT and plate clone formation experiments were applied to detect the proliferation of cells in each group;ELISA kits were used to measure the expression of interleukin(IL)-1β,IL-6 and tumor necrosis factor-α(TNF-α)in various groups;flow cytometry was applied to detect the apoptosis in various groups;Western blot was applied to detect the expression of proliferation related proteins(PCNA),apoptosis related proteins(Bcl-2,Bax),and HMGB1-RAGE signaling pathway related proteins(HMGB1,RAGE)in each group.Results Compared with the control group,the survival rate,clone number,PCNA and Bcl-2 proteins expression of HK-2 cells decreased in the model group,but the apoptosis rate,IL-1β,IL-6,TNF-α,Bax,HMGB1 and RAGE proteins expression increased(P<0.05).Compared with the model group,the survival rate,clone number,PCNA and Bcl-2 proteins expression of HK-2 cells increased in L-ART and H-ART groups,but the apoptosis rate,IL-1β,IL-6,TNF-α,Bax,HMGB1 and RAGE proteins expression decreased(P<0.05).Compared with the H-ART and H-ART+pcDNA NC groups,the survival rate,clone number,PCNA and Bcl-2 proteins expression of HK-2 cells decreased in the H-ART+pcDNA-HMBB1 group,but the apoptosis rate,IL-1β,IL-6,TNF-α,Bax,HMGB1 and RAGE proteins expression increased(P<0.05).Conclusion ART may suppress inflammatory response and cell apoptosis,promote cell proliferation,and alleviate H/R-induced injury of renal proximal tubular HK-2 cells by inhibiting the HMGB1-RAGE signaling pathway.

Objective To investigate the effect of artesunate(ART)on hypoxia/reoxygenation(H/R)-induced injury of human renal proximal tubular HK-2 cells by regulating the high mobility group protein B1(HMGB1)-receptor of advanced glycation endproduct(RAGE)signaling pathway.Methods HK-2 cells cultured in vitro were stochastically separated into control group,model group,L-ART group(4 μg/ml ART),H-ART group(16 μg/ml ART),H-ART+pcDNA NC group(16 μg/ml ART+transfected pcDNA NC plasmid),and H-ART+pcDNA-HMGB1 group(16 μg/ml ART+transfected pcDNA-HMGB1 plasmid).HK-2 cells in the control group were cultured normally,while the cells in the other groups were induced with hypoxia/reoxygenation(H/R).MTT and plate clone formation experiments were applied to detect the proliferation of cells in each group;ELISA kits were used to measure the expression of interleukin(IL)-1β,IL-6 and tumor necrosis factor-α(TNF-α)in various groups;flow cytometry was applied to detect the apoptosis in various groups;Western blot was applied to detect the expression of proliferation related proteins(PCNA),apoptosis related proteins(Bcl-2,Bax),and HMGB1-RAGE signaling pathway related proteins(HMGB1,RAGE)in each group.Results Compared with the control group,the survival rate,clone number,PCNA and Bcl-2 proteins expression of HK-2 cells decreased in the model group,but the apoptosis rate,IL-1β,IL-6,TNF-α,Bax,HMGB1 and RAGE proteins expression increased(P<0.05).Compared with the model group,the survival rate,clone number,PCNA and Bcl-2 proteins expression of HK-2 cells increased in L-ART and H-ART groups,but the apoptosis rate,IL-1β,IL-6,TNF-α,Bax,HMGB1 and RAGE proteins expression decreased(P<0.05).Compared with the H-ART and H-ART+pcDNA NC groups,the survival rate,clone number,PCNA and Bcl-2 proteins expression of HK-2 cells decreased in the H-ART+pcDNA-HMBB1 group,but the apoptosis rate,IL-1β,IL-6,TNF-α,Bax,HMGB1 and RAGE proteins expression increased(P<0.05).Conclusion ART may suppress inflammatory response and cell apoptosis,promote cell proliferation,and alleviate H/R-induced injury of renal proximal tubular HK-2 cells by inhibiting the HMGB1-RAGE signaling pathway.

Chronic diarrhea is a common complaint in gastroentology department,which is classified into a variety of types.While as eosinophilic gastroenteritis is a rare cause.A 50-year-old male patient was admitted with a 2-year history of diarrhea worsened for 10 months.Fasting could alleviate the diarrhea.Laboratory findings demonstrated anemia,low vitamins and minerals,fat malabsorption and abnormal D-xylose absorption test,delayed gastric emptying.According to the endoscopic biopsy of gastrointestinal mucosa,the diagnosis of eosinophilic gastroenteritis was made.Diabetic neuropathy may aggravate the symptom.The diarrhea resolved after the administration of steroids.

Objective To investigate the relationship between serum visfatin level and coronary artery stenosis.Methods Based on coronary angiography,85 patients were diagnosed as coronary heart disease.According to oral glucose tolerance test,these patients were divided into 3 groups,34 patients with normal glucose tolerance(CHD group),25 with impaired glucose regulation(CIG group),and 26 with type 2 diabetes mellitus(CDM group).30 non-comary heart disease subjects with normal glucose tolerance were selected as the control group(CON group),and they underwent coronary CT angiography scan and were confirmed coronary disease-free.Blood pressure,body mass index(BMI),waist circumference(WC),waist hip ratio(WHR),fasting plasma glucose(FPG),blood lipid analysis,fasting insulin,and HbA1C were determined.Serum visfatin concentration was assayed and the status of coronary artery was assessed.Coronary artery stenosis was screened by coronary interventional angiography and assessed by Gemini scoring system in CHD,CIG,and CDM groups.Results Compared with control group,serum visfatin in CHD,CIG,and CDM groups were significantly higher(all P<0.05).Compared with CHD group,serum visfatin in CIG and CDM groups were significantly higher(all P<0.05).The correlation analysis showed that serum visfatin level was positively correlated with the involved branches of coronary arteries(r=0.807,P<0.01),serum visfatin level was positively related with Gensini coronary artery score(r=0.669,P<0.01).Visfatin was also positively correlated with WC,WHR,triglyceride(TG,r=0.200,P=0.032,r=0.185,P=0.047,r=0.321,P<0.01),while high density lipoprotein cholesterol(HDL-C)was negatively correlated with visfatin(r=-0.354,P<0.01).Multiple regression analysis showed that senlm hvel of TG and WC were the main influencing factors of visfatin.Conclusion (1)The level of serum visfatin may reflect the severity of coronary artery stenosis,detection of visfatin helps to make early diagnosis of CHD.(2)The raised serum level of visfatin in comary heart disease patients with imparied glucose tolerance is consistent with clinical evidence that diabetic patients have more severe coronary diseases.(3)WC and serum TG are main inilucencing factors,suggesting that visfatin is correlated with abdominal obesity.

Objective To investigate the operative indications and operation techniques for augmentative plate fixation in treatment of femoral shaft atrophic nonunions subsequent to intramedullary fixation. Methods Twelve femoral nonunions after internal fixation with intramedullary nailing were treated with augmentative plate internal fixation and bone graft from June 1999 to June 2008. All femoral nonunions were caused by insecure fixation of the intramedullary nailing, in which a rotational instability of the fracture site was verified in all the patients during operation. Minimally invasive removal of the granulation tissue at fracture site and the sclerotic bone was dccorticated. The adequate lilac bone was tiled longitudinally on the nonunion gap and the cortical bone bed. The fixation involved the limited-contact dynamic titanium plate with 5-6 holes, 3.0 mm Kirschner wire and 4-6 double cortex cortical screw fixation.Protective weight-bearing was given after surgery and the tunction was evaluated at 1,3, 6 and 12 months with imaging. Results All patients were followed up for 7-26 months ( average 17.4 months), which showed radiological solid union (7-12 months, average 9.4 months) and clinical union (5-9 months, average 7.1 months ). The operation lasted for 50-120 minutes ( average 77.5 minutes), with blood volume of 150-350 ml ( average 252 ml). There were nine patients with bone pain, of whom the pain was relieved within one month in seven patients and three months in two. No infection, hardware loosening or breaking were found. Conclusion The plate augmentation and cancellous bone grafting leaving the nail in situ can be an effective solution for nonisthmal femoral nonunion, bone defect and failed exchange nailing.

ObjectiveTo compare the outcomes and indications between exchange nailing (EN) and augmentation plating (AP) with a nail left in situ for femoral shaft hypertrophic nonunion after femoral nailing. MethodsFrom April 1998 to June 2009, 20 patients with femoral shaft hypertrophic nonunions after femoral nailing were treated with EN (11 patients) and AP (9 patients) respectively. There were no significant differences between the two groups with respect to the patient's age, gender, associated injuries, anatomical location and type of femoral fracture. Patients were evaluated by imaging and clinical function at 1, 2, 3, 4,6, and 12 months after surgery, and then every year postoperatively, to observe the callus and the recovery condition of the affected limb function. Fisher exact test and t'-test were performed to compare the outcome and complications respectively. ResultsAn unpaired t'-test showed no significant differences with respect to follow-up time, operating time, intraoperative blood loss, postoperative drainage, length of stay, time to radiographic union, time to clinical union, and AAOS score between the two groups. The cost of hospitalizations in the EN group was higher than in the AP group(t'=16.4, P=0.013). Four nonunions in the EN group failed to achieve union, which 3 patients were subsequently treated with AP and simultaneous autogenous bone grafting and 1 patient was treated with nail dynamization. All 9 hypertrophic nonunions in the AP group obtained osseous union. Fisher exact test showed a higher nonunion rate of EN compared with AP (χ2=6.01 ,P=0.008). ConclusionEN has been an excellent choice for aseptic isthmal femoral nonunion without a large bone defect subsequent to intramedullary fracture fixation, and AP can be an effective solution in cases of nonisthmal femoral nonunion and bone defect and failed exchange nailing.

ObjectiveTo analysis the clinical features of thoracic spine and spinal cord injury (SCI) and summarize the inclusive standard of cellular transplant clinical trial for SCI.MethodsThe data of 72 cases with thoracic spine and spinal cord injury from 1990 to 2005 were analyzed retrospectively.ResultsMean follow-up period was 20 months (6～48 months). There was no recovery in 12 spinal cord injury without radiographic abnormality (SCIWORA) patients, but improvement of urine function in 4 cases. 5 cases of 52 fracture-dislocation complete injury were improved to grade B (sense recovery), rate of recovery was 9.6%; recovery rate was 62.5% in incomplete injury. Sense recovery of all cases was better than motor recovery. Partial cases appeared spasm paralysis relief.ConclusionIncidence rate of complete injury is high and recovery is bad in thoracic spine and spinal cord injury. The inclusive standard of cellular transplant clinical trial for SCI is old complete thoracic spinal cord injury without residual compression.