1.Isometric exercise reduces resting blood pressure:a meta-analysis of moderating factors and dose effects
Yang JIANG ; Hao PENG ; Yanping SONG ; Na YAO ; Yueyu SONG ; Xingxiao YIN ; Yanqi LI ; Qigang CHEN
Chinese Journal of Tissue Engineering Research 2026;30(4):975-986
OBJECTIVE:Elevated blood pressure increases the risk of cardiovascular diseases.Isometric exercise training has been shown to significantly reduce resting blood pressure,but the factors influencing its effectiveness remain unclear,and specific application guidelines are yet to be established.This study aims to evaluate the impact of isometric exercise training on resting blood pressure through meta-analysis,explore its moderating factors,and provide evidence-based recommendations based on its dose-response relationship.METHODS:Following the PRISMA guidelines,a systematic search was conducted in PubMed,Embase,Cochrane Library,Scopus,and Web of Science databases using keywords"Isometric exercise training,""Systolic blood pressure,"and"Diastolic blood pressure,"covering literature up to September 2024.Randomized controlled trials involving isometric exercise training and resting blood pressure were included.Three independent researchers performed literature screening and data extraction,assessing bias risk and quality grades using the Risk of Bias 2.0 tool and GRADE framework.Main effect pooling,publication bias assessment,subgroup,and regression analysis were conducted using R software(version 4.3.4).RESULTS:A total of 28 articles(comprising 32 randomized controlled trials)involving 977 participants were included.(1)Meta-analysis results indicated that isometric exercise training significantly reduced resting systolic blood pressure(MD=-8.01,95%CI=-9.22 to-6.80,P<0.01,I2=18.20%,low evidence grade)and diastolic blood pressure(MD=-3.46,95%CI=-4.64 to-2.28,P<0.01,I2=0%,moderate evidence grade)compared to no exercise.(2)Subgroup analysis results revealed significant influences of gender,health status,exercise modality,frequency,intensity,duration,sets per session,rest duration,and baseline blood pressure on the main effects for both systolic(P<0.01)and diastolic blood pressure(P<0.05).(3)Regression analysis results did not show any significant influencing factors,but body mass index(β=-4.11,P=0.091)showed a significant negative trend on the main effect for systolic blood pressure.(4)No significant publication bias was observed in the meta-analysis results(P>0.05).CONCLUSION:(1)Isometric exercise training significantly lowers systolic(low evidence grade)and diastolic(moderate evidence grade)blood pressure with clinically meaningful thresholds.(2)Participant characteristics(gender,health status,baseline blood pressure,and body mass index)and isometric exercise training protocols(modality,frequency,intensity,duration,cycle,sets per session,and rest duration)influence its antihypertensive effects.(3)The article recommends the optimal blood pressure management prescription:three sessions per week,with four sets per session,each set lasting 2 minutes with a 2-minute rest,at an intensity of 95%HRpeak using isometric wall squat exercises;the intervention period can be adjusted around a 6-week node.Future high-quality research is urgently needed to further validate and support these conclusions.
2.Study on the safety and efficacy of micro-perfusion device for preserving isolated porcine limbs
Pengkai LI ; Zhaodi MI ; Shen LI ; Man YUAN ; Xiwei PENG ; Jia LÜ ; Sice WANG ; Zhibo JIA ; Xiangyu SONG ; Yixuan ZHU ; Chonghui LI ; Moling XIAO ; Wenjing XU ; Jiang PENG
Organ Transplantation 2026;17(3):422-431
Objective To evaluate the safety and efficacy of a self-developed micro-normothermic machine perfusion (NMP) system (micro-perfusion device) for preserving isolated porcine limbs. Methods Five healthy Landrace pigs were selected, and their left and right forelimbs were randomly divided into the NMP group and static cold storage (SCS) group. The NMP group was perfused with the self-developed micro-perfusion device and polymerized hemoglobin perfusate for 32 hours at normothermia, while the SCS group was preserved at 4 ℃. Hemodynamic parameters such as perfusion pressure and flow were monitored. The pH value, partial pressure of oxygen (PO2), lactic acid (Lac), creatine kinase (CK) and lactate dehydrogenase (LDH) in the perfusate were measured. Hematoxylin-eosin staining was used to assess the muscle tissue structure, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling was employed to evaluate muscle cell apoptosis, and immunohistochemistry staining was applied to detect the expressions of tumor necrosis factor (TNF)-α and interleukin (IL)-6. A mixed-effects model was used to analyze the effects of time and treatment methods on tissue structure, cell apoptosis and inflammatory factors. Results The device could stably maintain a perfusion pressure of (69±15) mmHg and a flow rate of (117±42) mL/min. The pH value and electrolytes of the perfusate were generally stable, with PO2 maintained at a high level. Lac was maintained at 5.38(3.81, 6.45) mmol/L, while CK and LDH increased over time. After 32 hours of perfusion in the NMP group, both the myocyte spacing and apoptosis rate were better than those in the SCS group. Mixed-effects model analysis showed that there were statistically significant differences in the effects of NMP treatment and SCS treatment on myocyte spacing and apoptosis rate per unit time (both P < 0.05). There were no statistically significant differences in TNF-α and IL-6 between the two groups, and mixed-effects model analysis showed no statistically significant differences in the effects of NMP treatment and SCS treatment on TNF-α and IL-6 per unit time (both P > 0.05). Conclusions The micro-perfusion device used in this study may achieve 32-hour normothermic preservation in a porcine limb amputation model, maintain basic metabolism and ionic homeostasis, reduce muscle structural damage and cell apoptosis without inducing additional inflammatory responses. This technology is expected to significantly extend the time window for replantation of amputated limbs in disaster rescue and long-distance transportation, providing an important technical basis for clinical translation and subsequent replantation research.
3.Isometric exercise reduces resting blood pressure:a meta-analysis of moderating factors and dose effects
Yang JIANG ; Hao PENG ; Yanping SONG ; Na YAO ; Yueyu SONG ; Xingxiao YIN ; Yanqi LI ; Qigang CHEN
Chinese Journal of Tissue Engineering Research 2026;30(4):975-986
OBJECTIVE:Elevated blood pressure increases the risk of cardiovascular diseases.Isometric exercise training has been shown to significantly reduce resting blood pressure,but the factors influencing its effectiveness remain unclear,and specific application guidelines are yet to be established.This study aims to evaluate the impact of isometric exercise training on resting blood pressure through meta-analysis,explore its moderating factors,and provide evidence-based recommendations based on its dose-response relationship.METHODS:Following the PRISMA guidelines,a systematic search was conducted in PubMed,Embase,Cochrane Library,Scopus,and Web of Science databases using keywords"Isometric exercise training,""Systolic blood pressure,"and"Diastolic blood pressure,"covering literature up to September 2024.Randomized controlled trials involving isometric exercise training and resting blood pressure were included.Three independent researchers performed literature screening and data extraction,assessing bias risk and quality grades using the Risk of Bias 2.0 tool and GRADE framework.Main effect pooling,publication bias assessment,subgroup,and regression analysis were conducted using R software(version 4.3.4).RESULTS:A total of 28 articles(comprising 32 randomized controlled trials)involving 977 participants were included.(1)Meta-analysis results indicated that isometric exercise training significantly reduced resting systolic blood pressure(MD=-8.01,95%CI=-9.22 to-6.80,P<0.01,I2=18.20%,low evidence grade)and diastolic blood pressure(MD=-3.46,95%CI=-4.64 to-2.28,P<0.01,I2=0%,moderate evidence grade)compared to no exercise.(2)Subgroup analysis results revealed significant influences of gender,health status,exercise modality,frequency,intensity,duration,sets per session,rest duration,and baseline blood pressure on the main effects for both systolic(P<0.01)and diastolic blood pressure(P<0.05).(3)Regression analysis results did not show any significant influencing factors,but body mass index(β=-4.11,P=0.091)showed a significant negative trend on the main effect for systolic blood pressure.(4)No significant publication bias was observed in the meta-analysis results(P>0.05).CONCLUSION:(1)Isometric exercise training significantly lowers systolic(low evidence grade)and diastolic(moderate evidence grade)blood pressure with clinically meaningful thresholds.(2)Participant characteristics(gender,health status,baseline blood pressure,and body mass index)and isometric exercise training protocols(modality,frequency,intensity,duration,cycle,sets per session,and rest duration)influence its antihypertensive effects.(3)The article recommends the optimal blood pressure management prescription:three sessions per week,with four sets per session,each set lasting 2 minutes with a 2-minute rest,at an intensity of 95%HRpeak using isometric wall squat exercises;the intervention period can be adjusted around a 6-week node.Future high-quality research is urgently needed to further validate and support these conclusions.
4.Ilizarov bone transport combined with antibiotic bone cement promotes junction healing of large tibial bone defect
Zhibo ZHANG ; Zhaolin WANG ; Zhigang WANG ; Peng LI ; Jianhao JIANG ; Kai ZHANG ; Shuye YANG ; Gangqiang DU
Chinese Journal of Tissue Engineering Research 2025;29(10):2038-2043
BACKGROUND:Ilizarov bone transport is very effective in the treatment of open large tibial bone defects,but there are still complications,among which the difficulty of junction healing is one of the difficult points in treatment. OBJECTIVE:To investigate the effect of Ilizarov bone transport combined with antibiotic bone cement on junction healing after operation of open large tibial bone defect. METHODS:Totally 51 patients with open large tibial bone defect(bone defect>4 cm)admitted to Binzhou Medical University Hospital from August 2010 to January 2022 were selected,of which 28 received Ilizarov bone transport alone(control group)and 23 received Ilizarov bone transport combined with antibiotic bone cement treatment(trial group).External fixation time,bone healing time,bone healing index,visual analog scale score during bone removal,bone defect limb function,junction healing and complications at the final follow-up were statistically compared between the two groups. RESULTS AND CONCLUSION:(1)All the 51 patients were followed up for a mean of(22.53±5.77)months.External fixation time,bone healing time,bone healing index,postoperative infection rate,and non-healing rate of junction were less in the trial group than those in the control group(P<0.05).There was no significant difference between the two groups in visual analog scale scores at 6 months after the second surgery and in the functional excellence and good rate of limb with bone defect at the final follow-up(P>0.05).(2)These findings indicate that compared with the Ilizarov bone transport alone,Ilizarov bone transport combined with antibiotic bone cement treatment can promote the healing of open tibial fracture junction and increase the rate of bone healing.
5.NLUS-VQA: construction and evaluation of a visual question answering model for neonatal lung ultrasound diagnosis
Xuming TONG ; Jiangang CHEN ; Yiran WANG ; Xiqing ZHAO ; Yanhong YUAN ; Zishuo WANG ; Peng JIANG ; Qingyao XIONG ; Renxing LI ; Xueli WANG ; Jing LIU
Chinese Journal of Perinatal Medicine 2025;28(11):917-928
Objective:To develop and evaluate a medical visual question answering (VQA) model for neonatal lung ultrasound (LUS) images to enhance intelligent auxiliary diagnosis of neonatal pulmonary diseases.Methods:Using data from neonates admitted to Beijing Obstetrics and Gynecology Hospital, Capital Medical University (January 2023 to December 2024), an image-question-answer dataset comprising 251 LUS images was constructed [43 pneumonia (17.1%), 42 neonatal respiratory distress syndrome (16.7%), 83 transient tachypnea (33.1%), and 83 normal (33.1%) images] with a four-tier medical question-answer framework. Building upon the Qwen2.5-VL-7B base model and integrating LoRA fine-tuning with chain-of-thought prompting, we developed the NLUS-VQA model to enhance visual-language semantic alignment and enable stepwise clinical reasoning, achieving efficient small-sample adaptation. Model performance was comprehensively assessed through natural language generation metrics (BLEU-4, ROUGE-1/2/L), qualitative evaluation of characteristic recognition, and clinical consistency analysis.Results:(1) Quantitative evaluation demonstrated that NLUS-VQA achieved scores of 22.38 (BLEU-4), 48.26 (ROUGE-1), 22.40 (ROUGE-2), and 37.20 (ROUGE-L), representing significant improvements over baseline models. (2) Qualitatively, the model exhibited strong performance in identifying lung consolidation, coalescent B-lines, and snowflake signs, with its chain-of-thought strategy enhancing clinical interpretability and answer accuracy. (3) Clinically, NLUS-VQA achieved a Cohen's Kappa coefficient of 0.78 and diagnostic accuracy of 80.8% (21/26), indicating substantial agreement with clinical experts.Conclusion:The NLUS-VQA model demonstrates robust interpretability in recognizing key sonographic patterns (e.g. lung consolidation, confluent B-lines, and snowflake signs), providing a scalable framework for small-sample medical image analysis, though diagnostic performance on complex conditions remains limited by dataset scale and minority class representation.
6.Construction and application of a quality control and improvement system for metabolic and bariatric surgery in Beijing
Peirong TIAN ; Mengyi LI ; Jingli LIU ; Rixing BAI ; Jingtao BI ; Guanglong DONG ; Yanmin DU ; Jiagang HAN ; Wei HAN ; Yong JIANG ; Yuanxin LI ; Zhifei LI ; Hongwei LIN ; Diangang LIU ; Yang LIU ; Fanqiang MENG ; Runhong NI ; Jinghai SONG ; Qiang XU ; Wenmao YAN ; Nengwei ZHANG ; Chaohui ZHONG ; Peng ZHANG ; Zhongtao ZHANG
Chinese Journal of Surgery 2025;63(7):624-629
Objective:To establish and assess the quality control and improvement system for metabolic and bariatric surgery in Beijing.Methods:Based on relevant documents from the National Health Commission and the Beijing Municipal Health Commission,and referencing the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) by the American Society for Metabolic and Bariatric Surgery,a quality control system was developed under the Beijing Quality Control and Improvement Center of Metabolic and Bariatric Surgery. The system incorporated on-site evaluations,data registration,and specialized training. From May to December 2023,on-site assessments were conducted at 21 hospitals in Beijing performing bariatric surgery,evaluating personnel qualifications,infrastructure,clinical workflows,and postoperative follow-up. A quality control database was created to collect real-time surgical data,and training was provided for data entry and professional skills. Assessment results were classified as excellent,qualified,or needing improvement,with rectification suggestions offered and follow-up visits conducted to track progress.Results:All 21 hospitals achieved a 100% compliance rate for surgical indications, 16 (76.2%) met standardized surgical operation criteria,and 14 (66.7%) had standardized postoperative management. However,only 5 (23.8%) achieved a 12-month postoperative follow-up rate of ≥60%,and 4 (19.1%) had established specialized databases. Key challenges included insufficient specialized staffing (19.1%), lack of multidisciplinary collaboration (47.6%), inadequate equipment (57.1%), and low follow-up rates (57.1%). The database collected data from over 2 000 patients across 111 fields. After rectification, specialized database coverage rose to 61.9% (13 hospitals). Multi-level training programs developed backbone physicians and specialized nurses,significantly addressing the shortage of specialized personnel.Conclusion:The quality control system established in this study,through the integration of on-site evaluation,data registration,and specialized training,effectively enhances the standardization of surgical practices and data management capabilities.
7.Effects of normal body weight and overweight status on metabolism of sufentanil in patients with same CYP3A4/5 genotype:A prospective clinical study
Guanlei LIU ; Ying JIANG ; Bo YANG ; Zhigang QIN ; Liyuan FENG ; Zhengwei XUE ; Fang QIU ; Chunmei CHEN ; Wenzhong ZOU ; Peng LI ; Jianteng GU
Journal of Army Medical University 2025;47(22):2774-2782
Objective To explore the pharmacokinetic characteristics of sufentanil in individuals with normal body mass index(BMI),overweight BMI,and different CYP3A4/5 enzyme genotypes.Methods The patients receiving laparoscopic surgery under general anesthesia in the First Affiliated Hospital of Army Medical University from November 2020 to September 2021 were prospectively recruited in this study.Before the operation,the oral swabs were collected from all the patients for genotyping using the human CYP3A4/5 gene kit.Based on the potential impact of combination of their polymorphisms on sufentanil metabolism and the proportion of different genotype combinations of CYP3A4/5 enzymes,the patients were divided into groups I(3A4 homozygous mutation or 3A4 heterozygous mutation+3A5 homozygous mutation),II(3A4 heterozygous mutation+3A5 heterozygous mutation),and III(3A4 wild type or 3A4 heterozygous mutation+3A5 wild type).According to their BMI,they were also assigned into a normal body weight group(18.5~24.0 kg/m2)and an overweight group(24~<28 kg/m2),and the differences in drug metabolism parameters were statistically analyze between the 2 groups.After routine general anesthesia induction(sufentanil 0.5 μg/kg),venous blood samples were collected to detect the changes in its concentration using high performance liquid chromatography-mass spectrometry(HPLC-MS).The pharmacokinetic data of sufentanil were calculated between the normal BMI group and overweight group in all participants and between the 2 body weight groups among those with different genotype combinations.Results Among the 90 participants completing the blood drug concentration test,8 patients had their blood samples contaminated(including 1 case with an anesthesia duration of<2 h),and 3 were excluded due to low weight or overweight.Eventually,79 participants were included in the pharmacokinetic analysis on the normal body weight group and the overweight group.Compared with the normal body weight group,the central compartment volume of distribution in the overweight group was significantly reduced(P<0.05),while no obvious differences were observed between the 2 groups in terms of peripheral compartment volume of distribution,total clearance rate,peripheral compartment clearance rate,distribution half-life,clearance half-life,and area under the blood concentration-time curve.In group Ⅰ(n=26),the overweight patients(n=13)had significantly reduced central compartment volume of distribution,peripheral compartment volume of distribution,and peripheral compartment clearance rate when compared with the normal body weight patients(n=13)(P<0.05),while no differences were observed in other pharmacokinetic parameters.In groups Ⅱ(n=25)and Ⅲ(n=28),the overweight patients and normal body weight patients had no statistical differences in all pharmacokinetic parameters.Conclusion Among the patients with the same genotype combination of CYP3A4/5 mutations,there was no difference in the metabolism of sufentanil between the overweight and normal weight patients.Additionally,in the population of 3A4 homozygous mutation or 3A4 heterozygous mutation+3A5 homozygous mutation,the overweight patients have smaller peripheral distribution range of sufentanil,and weakened metabolic process.
8.Impact of early antimicrobial therapy on clinical outcomes in patients with suspected sepsis in emergency and outpatient settings: a prospective cohort study.
Xianxian XU ; Hongqing SHEN ; Weimin ZHU ; Ping LI ; Peng YANG ; Renfei SHAN ; Nanjin CHEN ; Yongpo JIANG
Chinese Critical Care Medicine 2025;37(4):337-342
OBJECTIVE:
To investigate the impact of early antimicrobial therapy on the prognosis of patients with suspected sepsis in emergency and outpatient settings.
METHODS:
A prospective cohort study was conducted. Patients with suspected sepsis admitted to the emergency department of Taizhou Hospital, Zhejiang Province, from May 1, 2022, to July 31, 2023, were enrolled. Participants were divided into an early group (0-1 hour) and a delayed group (> 1 hour) according to duration from admission to antimicrobial administration. General information, initial vital signs, laboratory parameters within 24 hours after admission, disease severity scores, vasoactive drug usage, and clinical outcomes of the patient were collected. Kaplan-Meier survival curve was used to analyze 28-day survival. Multivariate Cox proportional hazards regression was performed to identify independent risk factors for prognosis of the patients with suspected sepsis in emergency and outpatient settings. Sensitivity analyses were conducted through subgroup analyses.
RESULTS:
A total of 143 patients with suspected sepsis were enrolled in the analysis, with 66 patients in the early group and 77 in the delayed group. No statistically significant differences were observed in baseline characteristics (age, gender, vital signs, laboratory parameters, disease severity scores) or clinical outcomes [vasoactive drug usage rate, mechanical ventilation duration, length of intensive care unit (ICU) stay, total hospitalization duration] between the two groups. The 28-day mortality, multidrug resistance rate and sepsis confirmation rate did not differ significantly between the early group and delay group [28-day mortality: 18.2% (12/66) vs. 20.8% (16/77), multidrug resistance rate: 3.0% (2/66) vs. 2.6% (2/77), sepsis confirmation rate: 87.9% (58/66) vs. 88.3% (68/77), all P > 0.05]. Kaplan-Meier survival curve analysis showed no difference in 28-day cumulative survival between the two groups (Log-Rank test: χ2 = 2.528, P = 0.112). Multivariate Cox proportional hazards regression identified vasoactive drug usage [hazard ration (HR) = 2.465, 95% confidence interval (95%CI) was 1.019-5.961, P = 0.045] and endotracheal intubation (HR = 5.516, 95%CI was 2.195-13.858, P < 0.001) as independent risk factors for 28-day death of the patients with suspected sepsis in emergency and outpatient settings. Further exploration of the impact of early antimicrobial therapy on 28-day death in different subgroups of the patients with suspected sepsis in emergency and outpatient settings was conducted through subgroup analysis. The results showed that in the patients with different ages (< 60 years old: HR = 1.214, 95%CI was 0.535-2.751, P = 0.643; ≥ 60 years old: HR = 2.085, 95%CI was 0.233-18.668, P = 0.511), sequential organ failure assessment (SOFA) scores (< 6: HR = 1.411, 95%CI was 0.482-4.128, P = 0.530; ≥ 6: HR = 0.869, 95%CI was 0.292-2.587, P = 0.801), shock indexes (< 1: HR = 1.095, 95%CI was 0.390-3.077, P = 0.863; ≥ 1: HR = 1.364, 95%CI was 0.458-4.059, P = 0.577) and whether diagnosed with sepsis or not (yes: HR = 0.943, 95%CI was 0.059-15.091, P = 0.967; no: HR = 1.207, 95%CI was 0.554-2.628, P = 0.636) subgroups, early usage of antibiotics had not shown any advantage in improving prognosis compared with delayed usage.
CONCLUSION
Early antimicrobial therapy does not improve the prognosis of patients with suspected sepsis in emergency and outpatient settings.
Humans
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Sepsis/drug therapy*
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Prospective Studies
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Prognosis
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Emergency Service, Hospital
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Outpatients
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Female
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Male
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Anti-Infective Agents/therapeutic use*
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Middle Aged
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Aged
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Proportional Hazards Models
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Treatment Outcome
9.The analysis of effect of serum containing Gegen Qinlian Decoction on regulating hypoxia-induced glucose metabolism in L02 Cells and related metabolic mechanisms
Yan YOU ; Hongjing CUI ; Chengcheng PENG ; Li JIANG ; Qiyun ZHANG ; Bingtao LI ; Guoliang XU
The Journal of Practical Medicine 2025;41(7):936-943
Objective The study aimedto investigate the effects and metabolic mechanisms of Gegen Qinlian Decoction(GQD)containing serum on hypoxia-induced glucose metabolism in L02 cells.Methods The effects of five hypoxia durations(6,12,18,24,and 48 hours)on glucose consumption and cell viability of L02 cells were examined under hypoxic conditions to determine the optimal hypoxia time.Normal hepatocytes served as the normal control group.L02 cells with hypoxia-induced reduction in glucose consumption were divided into several groups:hypoxia group,metformin 2 mmol/L group,and 25 g/kg GQD groups treated with 5%,10%,and 15%GQD contain-ing serum.Glucose consumption was used as an indicator of drug efficacy.High-resolution liquid chromatography tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS)was employed to collect metabolite signals from each group.Data were analyzed by using Progenesis QI software,and potential biomarkers were identified through online databases such as HMDB.Finally,metabolic pathways of potential biomarkers were analyzed via the Metabo Analyst 5.0 website.Results An 18 hour hypoxia period was identified as the optimal duration for the replication of the hypoxia-induced L02 cell model.GQD containing serums at 5%and 10%significantly increased glucose consumption in hypoxia-induced L02 cells after 18 hours.14 biomarkers of hypoxia-induced L02 cells were identified,with the levels of 13 biomarkers significantly increased and 1 biomarker significantly decreased.GQD containing serum notably regulated the levels of 3 biomarkers.Conclusion GQD containing serum might improve hypoxia-induced abnormal glucose metabolism in L02 cells and enhance glucose consumption by modulating glycero-phospholipid metabolism,glycosylphosphatidylinositol biosynthesis,and sphingolipid metabolism.
10.Genetic diversity,virulence factors,and antibiotic resistance of Listeria monocytogenes from livestock and poultry meat and clinical samples in Weifang during 2020-2023
Yi-meng WANG ; Ming-ming YU ; De-hui LIU ; Xiao-yan HAO ; Li-dan JIANG ; Zhi-peng REN
Chinese Journal of Zoonoses 2025;41(6):629-635
This study was aimed at understanding the antimicrobial resistance patterns,virulence characteristics,and phyloge-netic relationships of foodborne Listeria monocytogenes in Weifang.A total of 67 strains of Listeria monocytogenes were isolated from livestock,poultry meat,and clinical samples in Weifang between 2020 and 2023.The susceptibility of these isolates was determined through broth microdilution.Whole-genome sequencing and genetic characterization of these isolates were conducted.The 67 strains were divided into 12 STs,among which ST121,ST8,ST9,and ST87 predominated(76.12%).Eight groups of closely related strains were identified through cgMLST typing.Three Listeria pathogenicity islands and two genomic islands were identified in all strains:100%of the strains carried LIPI-1,5.97%carried LIPI-3,14.93%carried LIPI-4,2.99%carried LGI-2,and 4.48%of the strains carried LGI-3.No antibiotic resistance genes were found in any strains.All isolates were susceptible to ampicillin,penicillin,merope-nem,trimethoprim-sulfamethoxazole,and vancomycin.Five isolates were resistant to tetracycline,and three strains of ST87,one strain of ST8,one strain of ST224,and two strains of ST87 were simultaneously resistant to erythromycin.The tet(M)tetracycline re-sistance genes and msr(D)and mef(A)erythromycin resistance genes from three strains of ST87 and one strain of ST8 were carried by a phage similar to phi1605 in Erysipelothrix,with>95%identity.The tet(M)gene from the ST224 isolates was carried by a transposon similar to Tn5801_B15 in Enterococcus faecalis,with>95%identity.Drug-resistant strains of Listeria monocytogenes were found in livestock and poultry meat on sale in Weifang,particularly strains of type ST87 and ST224 simultaneously carrying highly pathogenic virulence islands,thus posing a threat to food safety and public health.These findings therefore warrant attention from relevant depart-ments and strengthened monitoring efforts.

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