1.Curcumin extraction and preparation and optimization of curcumin nanoparticles
Yuhang WANG ; Han ZHANG ; Chaojing ZHANG ; Xurong KOU ; Tongtong JING ; Rimei LIN ; Xinyu LIU ; Shilei LOU ; Hui YAN ; Cong SUN
Chinese Journal of Tissue Engineering Research 2026;30(2):362-374
BACKGROUND:Curcumin is the main active ingredient of turmeric and has significant medicinal value in anti-tumor,anti-inflammatory,antioxidant and other aspects.However,its poor water solubility,unstable chemical properties and easy decomposition lead to difficulty in extracting curcumin and low extraction yield.Therefore,it is particularly important to optimize the curcumin extraction method.OBJECTIVE:To enhance the extraction yield and utilization value of curcumin and optimize the curcumin extraction process and curcumin nanoparticle preparation process.METHODS:Curcumin was extracted from turmeric by ethanol extraction,ultrasonic extraction,ionic liquid extraction,enzyme extraction,and ionic liquid combined with ultrasonic assisted enzyme extraction.The curcumin extraction yield was detected by high performance liquid chromatography;the best extraction method was determined,and subsequent process optimization experiments were carried out.The curcumin extraction yield was the response value with the type of ionic liquid,reaction temperature,ultrasonic time,liquid-to-solid ratio,ionic liquid concentration,and enzyme-drug mass ratio as parameters.The optimal production process of ionic liquid combined with ultrasonic assisted enzyme extraction was determined by single factor combined response surface experiment.The optimal process for preparing curcumin nanoparticles by ionic crosslinking method was determined by single factor combined response surface experiment with acetic acid concentration,chitosan to sodium tripolyphosphate mass ratio,stirring rate,curcumin mass concentration,sodium tripolyphosphate mass concentration,and chitosan mass concentration as parameters,and drug encapsulation efficiency as response value.Curcumin nanoparticles were prepared under the optimal process,and the particle size,polydispersity index,Zata potential value,drug loading,stability,hemolysis rate,and antioxidant capacity in vivo and in vitro of the nanoparticles were detected.RESULTS AND CONCLUSION:(1)Among the five extraction methods,the curcumin yield of ionic liquid combined with ultrasound-assisted enzyme extraction was the highest,and this method was selected as the curcumin extraction method for subsequent experiments.The results of single factor combined response surface experiment showed that the optimal process for curcumin extraction was:ionic liquid selected 1-hexyl-3-methylimidazolium chloride,reaction temperature 55 ℃,liquid-to-solid ratio 40 mL/g,ultrasound time 57 minutes,ionic liquid concentration 57%,enzyme-drug mass ratio 3.5:10,and the obtained turmeric extraction yield was 3.10%.The optimal preparation process of curcumin nanoparticles was:glacial acetic acid concentration 0.5%,chitosan and sodium tripolyphosphate mass ratio 5.0:1,stirring speed 150 r/min,curcumin mass concentration 2.23 mg/mL,sodium tripolyphosphate mass concentration 1.45 mg/mL,chitosan mass concentration 3.63 mg/mL,and the obtained drug encapsulation efficiency was 90.61%.(2)The drug loading of curcumin nanoparticles was(14.49±0.23)%,the average particle size was(76.95±1.65)nm,the polydispersity coefficient was 0.15±0.02,and the Zata potential value was(32.37±1.46)mV.The curcumin nanoparticles had good stability and blood compatibility,did not induce hemolysis,and had stronger antioxidant capacity in vivo and in vitro than free curcumin.(3)The results show that the process optimization not only solves the problems of low extraction yield,poor solubility,and low bioavailability of curcumin,but also enhances its antioxidant activity in vivo and in vitro.
2.Assessing High-density Y-SNP Panels for Paternal Haplogroup Assignment in Forensic Practice
De-Qin ZHANG ; Chun-Nian WANG ; Lin-Lin LOU ; Meng NI ; Jing GAO ; Jiang HUANG ; Li JIANG
Progress in Biochemistry and Biophysics 2026;53(2):458-469
ObjectiveThe accuracy of Y-chromosome haplogroup assignment is crucial for tracing paternal lineage in male samples. With the advancement of high-throughput sequencing technologies, high-density Y-SNP genotyping from whole-genome or array-based data has become a standard method for determiningY-chromosome haplogroups. This study systematically evaluated the performance of 4 commonly used high-density SNP genotyping systems—namely, the Global Screening Array (GSA), Chinese Genotyping Array (CGA), Affymetrix array, and the 1240K capture panel—for haplogroup assignment. This work provides a reference for data comparison across different systems. MethodsWe extracted genotype data for the 4 Y-SNP panels from 30× whole-genome sequencing (WGS) data of 1 590 male samples from the 1000 Genomes Project. Additionally, GSA array genotype data from 384 relative pairs (spanning 1st- to 12th-degree relationships) from 109 Chinese Han families were collected. Haplogroup assignment was performed using Y-LineageTracker v1.3.0 software. We assessed the concordance and resolution of haplogroup assignments between the four Y-SNP panels and the WGS data. The consistency and resolution of haplogroup assignments were also evaluated for both the 1000 Genomes Project samples and the 109 family samples collected in this study. Furthermore, the impact of varying numbers of Y-SNPs on haplogroup assignment was examined. ResultsThe GSA and CGA panels demonstrated superior resolution and discrimination of haplogroup subclades compared with the other two panels. The haplogroup assignments from the GSA, CGA, and 1240K panels showed high concordance with WGS data, with consistency rates exceeding 88.70%, whereas the Affymetrix platform exhibited a significantly lower consistency rate of 61.89%. Specifically, the GSA and CGA panels consistently demonstrated superior performance compared with the other two panels in the assignment of haplogroups O-M175 and H-L901, achieving complete concordance (100%) for both haplogroups. In contrast, the Affymetrix panel erroneously assigned all individuals belonging to haplogroup O-M175 to haplogroup K2-M526. Furthermore, its accuracy for haplogroup H-L901 was exceedingly low, at merely 1.41%. This poor performance was characterized by the misassignment of 98.59% of H-L901 samples—specifically, 1.41% to J-M304 and a predominant 97.18% to F-M89. For haplogroup R-M207, all four panels exhibited uniformly high levels of consistency, with concordance values exceeding 94.00%. Notably, for haplogroup E-M96, the 1240K and Affymetrix panels outperformed the GSA and CGA panels in terms of concordance, representing the first instance in which these two panels surpassed the latter. Conversely, for haplogroups J-M304, Q-M242, and I-M170, all 4 panels showed relatively elevated misclassification rates, with the Affymetrix array demonstrating the poorest overall performance. None of the four panels showed any discordant haplogroup assignments among the familial relative pairs analyzed. A positive correlation was observed between the number of Y-SNPs (ranging from 1 000 to 10 000) and classification consistency; however, classification consistency plateaued when the number of Y-SNPs exceeded 10 000. Furthermore, a random sampling analysis conducted on the GSA and CGA panels demonstrated that the haplogroup misclassification rate exhibited negligible fluctuation across the Y-SNP range of 500 to 1 000. Conversely, a marked enhancement in classification consistency was observed as the number of markers increased from 1 000 to 5 000, ultimately reaching a plateau within the interval of 5 000 to 8 000 markers. ConclusionThese findings indicate that the GSA and CGA panels provide high resolution and concordance, delivering reliable Y-haplogroup assignment for forensic investigations.
3.Assessing High-density Y-SNP Panels for Paternal Haplogroup Assignment in Forensic Practice
De-Qin ZHANG ; Chun-Nian WANG ; Lin-Lin LOU ; Meng NI ; Jing GAO ; Jiang HUANG ; Li JIANG
Progress in Biochemistry and Biophysics 2026;53(2):458-469
ObjectiveThe accuracy of Y-chromosome haplogroup assignment is crucial for tracing paternal lineage in male samples. With the advancement of high-throughput sequencing technologies, high-density Y-SNP genotyping from whole-genome or array-based data has become a standard method for determiningY-chromosome haplogroups. This study systematically evaluated the performance of 4 commonly used high-density SNP genotyping systems—namely, the Global Screening Array (GSA), Chinese Genotyping Array (CGA), Affymetrix array, and the 1240K capture panel—for haplogroup assignment. This work provides a reference for data comparison across different systems. MethodsWe extracted genotype data for the 4 Y-SNP panels from 30× whole-genome sequencing (WGS) data of 1 590 male samples from the 1000 Genomes Project. Additionally, GSA array genotype data from 384 relative pairs (spanning 1st- to 12th-degree relationships) from 109 Chinese Han families were collected. Haplogroup assignment was performed using Y-LineageTracker v1.3.0 software. We assessed the concordance and resolution of haplogroup assignments between the four Y-SNP panels and the WGS data. The consistency and resolution of haplogroup assignments were also evaluated for both the 1000 Genomes Project samples and the 109 family samples collected in this study. Furthermore, the impact of varying numbers of Y-SNPs on haplogroup assignment was examined. ResultsThe GSA and CGA panels demonstrated superior resolution and discrimination of haplogroup subclades compared with the other two panels. The haplogroup assignments from the GSA, CGA, and 1240K panels showed high concordance with WGS data, with consistency rates exceeding 88.70%, whereas the Affymetrix platform exhibited a significantly lower consistency rate of 61.89%. Specifically, the GSA and CGA panels consistently demonstrated superior performance compared with the other two panels in the assignment of haplogroups O-M175 and H-L901, achieving complete concordance (100%) for both haplogroups. In contrast, the Affymetrix panel erroneously assigned all individuals belonging to haplogroup O-M175 to haplogroup K2-M526. Furthermore, its accuracy for haplogroup H-L901 was exceedingly low, at merely 1.41%. This poor performance was characterized by the misassignment of 98.59% of H-L901 samples—specifically, 1.41% to J-M304 and a predominant 97.18% to F-M89. For haplogroup R-M207, all four panels exhibited uniformly high levels of consistency, with concordance values exceeding 94.00%. Notably, for haplogroup E-M96, the 1240K and Affymetrix panels outperformed the GSA and CGA panels in terms of concordance, representing the first instance in which these two panels surpassed the latter. Conversely, for haplogroups J-M304, Q-M242, and I-M170, all 4 panels showed relatively elevated misclassification rates, with the Affymetrix array demonstrating the poorest overall performance. None of the four panels showed any discordant haplogroup assignments among the familial relative pairs analyzed. A positive correlation was observed between the number of Y-SNPs (ranging from 1 000 to 10 000) and classification consistency; however, classification consistency plateaued when the number of Y-SNPs exceeded 10 000. Furthermore, a random sampling analysis conducted on the GSA and CGA panels demonstrated that the haplogroup misclassification rate exhibited negligible fluctuation across the Y-SNP range of 500 to 1 000. Conversely, a marked enhancement in classification consistency was observed as the number of markers increased from 1 000 to 5 000, ultimately reaching a plateau within the interval of 5 000 to 8 000 markers. ConclusionThese findings indicate that the GSA and CGA panels provide high resolution and concordance, delivering reliable Y-haplogroup assignment for forensic investigations.
4.Curcumin extraction and preparation and optimization of curcumin nanoparticles
Yuhang WANG ; Han ZHANG ; Chaojing ZHANG ; Xurong KOU ; Tongtong JING ; Rimei LIN ; Xinyu LIU ; Shilei LOU ; Hui YAN ; Cong SUN
Chinese Journal of Tissue Engineering Research 2026;30(2):362-374
BACKGROUND:Curcumin is the main active ingredient of turmeric and has significant medicinal value in anti-tumor,anti-inflammatory,antioxidant and other aspects.However,its poor water solubility,unstable chemical properties and easy decomposition lead to difficulty in extracting curcumin and low extraction yield.Therefore,it is particularly important to optimize the curcumin extraction method.OBJECTIVE:To enhance the extraction yield and utilization value of curcumin and optimize the curcumin extraction process and curcumin nanoparticle preparation process.METHODS:Curcumin was extracted from turmeric by ethanol extraction,ultrasonic extraction,ionic liquid extraction,enzyme extraction,and ionic liquid combined with ultrasonic assisted enzyme extraction.The curcumin extraction yield was detected by high performance liquid chromatography;the best extraction method was determined,and subsequent process optimization experiments were carried out.The curcumin extraction yield was the response value with the type of ionic liquid,reaction temperature,ultrasonic time,liquid-to-solid ratio,ionic liquid concentration,and enzyme-drug mass ratio as parameters.The optimal production process of ionic liquid combined with ultrasonic assisted enzyme extraction was determined by single factor combined response surface experiment.The optimal process for preparing curcumin nanoparticles by ionic crosslinking method was determined by single factor combined response surface experiment with acetic acid concentration,chitosan to sodium tripolyphosphate mass ratio,stirring rate,curcumin mass concentration,sodium tripolyphosphate mass concentration,and chitosan mass concentration as parameters,and drug encapsulation efficiency as response value.Curcumin nanoparticles were prepared under the optimal process,and the particle size,polydispersity index,Zata potential value,drug loading,stability,hemolysis rate,and antioxidant capacity in vivo and in vitro of the nanoparticles were detected.RESULTS AND CONCLUSION:(1)Among the five extraction methods,the curcumin yield of ionic liquid combined with ultrasound-assisted enzyme extraction was the highest,and this method was selected as the curcumin extraction method for subsequent experiments.The results of single factor combined response surface experiment showed that the optimal process for curcumin extraction was:ionic liquid selected 1-hexyl-3-methylimidazolium chloride,reaction temperature 55 ℃,liquid-to-solid ratio 40 mL/g,ultrasound time 57 minutes,ionic liquid concentration 57%,enzyme-drug mass ratio 3.5:10,and the obtained turmeric extraction yield was 3.10%.The optimal preparation process of curcumin nanoparticles was:glacial acetic acid concentration 0.5%,chitosan and sodium tripolyphosphate mass ratio 5.0:1,stirring speed 150 r/min,curcumin mass concentration 2.23 mg/mL,sodium tripolyphosphate mass concentration 1.45 mg/mL,chitosan mass concentration 3.63 mg/mL,and the obtained drug encapsulation efficiency was 90.61%.(2)The drug loading of curcumin nanoparticles was(14.49±0.23)%,the average particle size was(76.95±1.65)nm,the polydispersity coefficient was 0.15±0.02,and the Zata potential value was(32.37±1.46)mV.The curcumin nanoparticles had good stability and blood compatibility,did not induce hemolysis,and had stronger antioxidant capacity in vivo and in vitro than free curcumin.(3)The results show that the process optimization not only solves the problems of low extraction yield,poor solubility,and low bioavailability of curcumin,but also enhances its antioxidant activity in vivo and in vitro.
5.Chinese expert consensus on the clinical application of recombinant human thyroid-stimulating hormone (2025 edition)
Chentian SHEN ; Yushen GU ; Hui TAN ; Anren KUANG ; Sijin LI ; Yaming LI ; Jing WANG ; Ningyi JIANG ; Jian TAN ; Zhuoying WANG ; Shaoyan LIU ; Xiaoyi LI ; Jugao FANG ; Dingcun LUO ; Youben FAN ; Hui WANG ; Yuetao WANG ; Xuemei WANG ; Feng WANG ; Wei FU ; Feng SHI ; Xuegong LIU ; Zhongwei LÜ ; Yan XING ; Lin LI ; Hui YANG ; Jun XIN ; Yifan ZHANG ; Yue CHEN ; Yansong LIN ; Wei OUYANG ; Shuzhan YAO ; Changjiu ZHAO ; Xinming ZHAO ; Zairong GAO ; Dingde HUANG ; Qiang WEN ; Xingmin HAN ; Cen LOU ; Weibing MIAO ; Wei FAN ; Quanyong LUO ; Hongcheng SHI
Chinese Journal of Clinical Medicine 2026;33(5):932-944
The recombinant human thyroid-stimulating hormone (rhTSH) can be used for differentiated thyroid cancer (DTC) preparation before 131I therapy, and follow-up. Since its approval by the American Food and Drug Administration (FDA) in 1998, rhTSH has been clinically used in European countries, the United States, and other countries for nearly 30 years. In April 2024, China’s first independently developed rhTSH agent was approved. Based on clinical experience and evidence from domestic and international studies, an expert consensus on the application of rhTSH has been developed following thorough consultations among experts. The consensus offers evidence-based recommendations to guide the appropriate use of rhTSH in clinical practice.
6.Comparison of clinical efficacy between unilateral biportal endoscopy and percutaneous endoscopic transforaminal discectomy in treatment of lumbar disc herniation
Jing ZENG ; Yindong SONG ; Zhiguo WANG ; Aiju LOU ; Dongdong WU ; Bing XU ; Jiayi LIU ; Zili XIONG
Journal of Jilin University(Medicine Edition) 2025;51(5):1349-1357
Objective:To analyze the efficacies of unilateral biportal endoscopy(UBE)and percutaneous endoscopic transforaminal discectomy(PETD)in treatment of lumbar disc herniation(LDH),and to explore the optimal selection of minimally invasive surgical approaches for the The LDH patients.Methods:A retrospective analysis was performed on the clinical data of 64 LDH patients who underwent surgery at Liwan Central Hospital of Guangzhou City in Guangdong Province,between January 2020 and June 2024.The surgical approaches were determined through physician-patient communication,and the patients were divided into UBE group(n=30)and PETD group(n=34).The materials of patients were recorded including gender,age,body mass index(BMI),percentages of affected segments,course of disease,duration of hospitalization,operation duration,intraoperative blood loss,numbers of intraoperative fluoroscopy,total incision length,and time to full weight-bearing(WB).The therapeutic outcomes were evaluated using Oswestry disability index(ODI),Visual Analog Scale(VAS)scores for low back pain and leg pain,MacNab criteria,and spinal canal areas at the affected segment.the postoperative complications of the patients in two groups were analyzed.Results:There were no statistically significant differences in age,gender composition ratio,BMI,course of disease,and percentages of affected segments of the patients between UBE group and PETD group(P>0.05).Compared with PETD group,the intraoperative blood loss,total incision length,and time to full WB of the patients in UBE group were significantly increase(P<0.01),while the number of intraoperative fluoroscopy time was decreased(P<0.01).Compared with pre-operation,the ODI scores and VAS scores for low back and leg pain of the patients at final follow-up in both groups were decreased(P<0.01),and the spinal canal areas at the affected segments of the patients were increased(P<0.01).At final follow-up,compared with PETD group,the ODI score and VAS scores for low back and leg pain of patients in UBE group were decreased(P<0.01),while the spinal canal areas at the affected segments of the patients was increased(P<0.01).According to MacNab criteria,the percentages of excellent and good had no significant difference between two groups(P>0.05).The incidence of complication showed no statistical difference between two groups(P>0.05).Conclusion:Both UBE and PETD yield satisfactory outcomes in the treatment of single-segment LDH.PETD is less invasive and permits earlier time to full WB,whereas UBE provides more extensive decompression and superior long-term efficacy.The surgical approach selection should be individualized based on specific factors in the clinic.
7.Correlation between frequency of follow up and death under SDTM mode in advanced age patients with type 2 diabetes mellitus
Jing DAI ; Liubao GU ; Qinglin LOU ; Haidi WU
Chongqing Medicine 2025;54(1):43-45,51
Objective To conduct the standardized management on the advanced age(≥75 years old)outpatients with type 2 diabetes mellitus(T2DM)by adopting the staged diabetes targeted management(SDTM)mode,and to observe the correlation between the follow up frequency and death.Methods The ad-vanced age patients with T2DM participating in the SDTM mode in the diabetes clinic of a tertiary hospital in Jiangsu Province from September 2009 to September 2022 were retrospectively selected and divided into the survival and death groups according to whether or not the patient died.The correlation between the follow up frequency and death was analyzed.Results A total of 947 advanced age patients with T2DM participated in the follow up,the mean age was(82.1±4.7)years old,and the mean follow-up time was(7.5±3.2)years.A total of 169 cases died with a death rate of 17.8%.The Cox regression analysis showed that the annual average follow up frequency had the correlation with death;after correcting the factors such as age and gender,the an-nual average follow-up frequency of the patients was correlated with death(HR=0.880,95%CI:0.854-0.907,P<0.001).Conclusion Using the SDTM mode to conduct the standardized management on the advanced age patients with T2DM and increasing the follow-up frequency could reduce the death rate of the patients and im-prove their survival rate.
8.Mechanism of SOS1-IT1 promoting EZH2 expression in human endometrial cancer cells by regulating acetylation modification
Hong-Yang LIU ; Xue-Ling LOU ; Rong-Jing ZHANG ; Quan-Ling FENG ; Kai-Ge GUO ; Hao-Fan WANG ; Ying-Ying LI ; Jun-Hu WAN ; Lin-Dong ZHANG
Acta Anatomica Sinica 2025;56(4):444-451
Objective To explore the molecular mechanism by which SOS Ras/Rac guanine nucleotide exchange factor 1-intronic transcript 1(SOS1-IT1)affects enhancer of zeste homolog 2(EZH2)protein expression in endometrial cancer cells Ishikawa and RL95-2.Methods Lentiviral transfection of short hairpin RNA(shRNA)and overexpression plasmid were used in Ishikawa and RL95-2 cell lines to knock down and overexpress SOS1-IT1.The mechanism of EZH2 expression regulation was studied using Real-time PCR,Western blotting,and chromatin immunoprecipitation.Results The expression of SOS1-IT1 and EZH2 genes was positively correlated in endometrial cancer tissues.Knocking down SOS1-IT1 significantly reduces the expression of EZH2,inhibited the proliferation and migration of Ishikawa and RL95-2 cells,and could reduced the acetylation of histone H3 at position 27(H3K27)and the enrichment of CREB binding protein(CBP)in the EZH2 gene promoter region.Overexpression of SOS1-IT1 could increased the expression of EZH2 and enhance the acetylation of H3K27 and the enrichment of CBP.CBP could bind to SOS1-IT1 RNA,and this binding ability was weakened when CBP was knocked down.Conclusion SOS1-IT1 can promote the expression level of EZH2 in endometrial cancer cells Ishikawa and RL95-2 by regulating the acetylation modification level of the EZH2 gene promoter region,thereby affecting the proliferation and migration ability of endometrial cancer cells.
9.Construction of evaluation index system for clinical application of ventilator
Wei XIONG ; Ligang LOU ; Bin MAO ; Zhichen WANG ; Jing SUN ; Jingyi FENG
China Medical Equipment 2025;22(7):107-112
Objective:To establish a set of reasonable,reliable and easy-to-operate evaluation index system for the clinical application of ventilators,so as to carry out all-round clinical evaluation for application of ventilators.Methods:A research group on the evaluation index system for the clinical application of ventilators was formed by 5 clinical engineers,who came from the Department of Medical Engineering of the First Affiliated Hospital of Zhejiang University School of Medicine,to form a primary evaluation index system for the clinical application of ventilators through literature review and internal discussion,and invited 14 experts from different provinces and cities engaged in respiratory therapy or ventilator maintenance management,after two rounds of online discussion and optimization,the importance scores of each evaluation index were obtained by the Delphi method,and the relative importance of each evaluation index was calculated by analytic hierarchy process.An evaluation index system for the clinical application of ventilators was established from three dimensions:technical performance,clinical effect and after-sales service.The ventilators of brand A and brand B used in the hospital during the same period were selected,and the clinical application of the two different brands of ventilators was compared and evaluated by using the evaluation index system.Results:The constructed evaluation index system for clinical application of ventilator included 3 first-level indicators(technical performance,clinical effect and after-sale service),and 8 second-level indicators and 35 third-level indicators.The combined weight of indicators showed that the ratio of importance of"technical performance"of the first-level indicators accounted for more than half,and the relatively important indicators in the second-level indicators were successively design for safety,static performance,reliability,service quality and applicability.The comprehensive average score of ventilator A was 4.468 points,and that of ventilator B was 4.117 points.The overall performance of ventilator A was better than that of ventilator B in the evaluation of this round,which was consistent with the actually clinical application of the two ventilators.Conclusion:The evaluation index system for clinical application of ventilator can conduct comprehensive evaluation for the effect of clinical application of various kinds of ventilators,and clarify the advantages and disadvantages of various kinds of ventilators,and provide reference basis for medical institutions in selecting ventilator's brands,and for manufacturers in improving product's performance.
10.Isolation and identification of yak-derived Enterococcus from four provinces of Tibetan plateau and detection of virulence resistance genes and biofilms
Jiaojiao XIN ; Guiqin GAO ; Xiaolong ZHAO ; Yongzhi LOU ; Jing LI ; Pan CHANG ; Ren-de SONG ; Xiangying KONG ; Hongmei SHI ; Xiaolin LUO ; Zhuoma GESANG ; Sizhu SUOLANG ; Ga GONG
Chinese Journal of Veterinary Science 2025;45(2):289-297
This study aims to understand the epidemic distribution characteristics,antimicrobial resistance,virulence genes,and biofilm adhesion ability of Enterococcus in yaks on the Tibetan plateau.Three hundred and forty-six fresh yak fecal samples and 311 milk samples were collected from four provinces on the Tibetan plateau(Xizang,Sichuan,Gansu,Qinghai),totaling 657 sam-ples.Bacterial isolation and identification were conducted,followed by 16S rDNA gene detection and the construction of a systematic evolutionary tree.The isolated strains were tested for antimi-crobial resistance and virulence genes using PCR,and sensitivity tests were performed using 18 types of antibiotics.The biofilm adhesion ability of the isolated bacteria was determined using an improved semi-quantitative crystal violet staining method.The results showed that the total isola-tion rate of Enterococcus was 32.27%,with Sichuan having the highest at 60.23%,followed by Gansu,Qinghai,and Tibet autonomous region at 42.70%,23.47%,and 18.31%respectively.In terms of sample types,the isolation rate in fecal samples was 36.71%,and in milk samples,it was 27.33%.Through PCR amplification,bands of approximately 1 400 bp were obtained,and 5 strains were selected for evolutionary analysis,forming a separate cluster.Among the 212 isolated strains,a high resistance to clindamycin,quinupristin-dalfopristin,linezolid,levofloxacin,and erythromycin was observed,with various resistance phenomena,accounting for 60.85%.Only 5 out of 12 resist-ant genes were detected,namely erm(B),tet(L),tet(O),tet(M),and ant(6)-Ia.All 13 virulence genes were detected in Enterococcus,with detection rates in the range of 5.19%to 95.76%,where cpd was 95.75%,gelE was 91.98%,efaA was 86.79%,asal was 86.32%,and the rest ranged from 5.19%to 55.66%.The fsr virulence gene was not detected in Enterococcus from milk sources.Among the isolated strains,3.30%showed medium adhesive ability,48.58%showed weak adhesive ability,and 48.11%showed no adhesive ability.The above research revealed the preva-lence of yak derived Enterococcus,the carrying status of resistance and virulence genes,and the correlation between biofilm phenotypes,laying the foundation for mastering research data on yak-derived Enterococcus in the Tibetan plateau.

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