1.Effect of Simiaowan on Promoting Ileal Uric Acid Excretion by Modulating Gut Microbiota to Improve Intestinal Barrier Function and Upregulate ABCG2 Expression in Rats
Yuan ZHANG ; Zhongyou ZHANG ; Huilin FENG ; Lian DUAN ; Lingchun WANG ; Hao DAI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(1):101-112
ObjectiveTo investigate the effects of Simiaowan on intestinal barrier function and adenosine triphosphate (ATP) binding cassette transporter G2 (ABCG2) expression in hyperuricemic (HUA) rats, and elucidate its therapeutic mechanisms. MethodsForty male Sprague Dawley (SD) rats were randomized into a normal group, a model group, low-dose (282.6 mg·kg-1) and high-dose (565.2 mg·kg-1) Simiaowan groups, and a Benzbromarone (4.7 mg·kg-1) group. The HUA model was established via intraperitoneal injection of potassium oxonate (ip) combined with oral gavage of hypoxanthine (ig) for 14 days. Following modeling, treatments were administered for 14 days. Samples were collected and weighed 4 h after final dosing. Blood uric acid and hepatic function were analyzed. Histopathological changes were evaluated by hematoxylin-eosin (HE) staining, and Chiu's scoring was conducted. Enzyme-linked immunosorbent assay (ELISA) quantified tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), lipopolysaccharide (LPS), diamine oxidase (DAO), and D-lactic acid (D-LA) levels. Real-time polymerase chain reaction (Real-time PCR), Western blot, and immunohistochemistry assessed the expression of Claudin-1, Occludin, occludens-1 (ZO-1), and ABCG2 mRNAs and proteins. 16S rDNA amplicon sequencing characterized ileal microbiota. ResultsCompared with the normal group, the model group exhibited epithelial shedding in the ileal villus, structural disruption, infiltration of extensive inflammatory cells, and significantly elevated Chiu's scores (P<0.01). The DAO, TNF-α, IL-6, IL-1β, LPS, and D-LA levels in the ileum were markedly increased (P<0.01), while mRNA and protein expressions of Claudin 1, Occludin, ZO-1, and ABCG2, as well as positive staining area and proportion, were significantly reduced (P<0.01). Compared with the model group, the Simiaowan groups at all doses showed improved epithelial damage in the ileal villus, significantly lowered Chiu's scores (P<0.01), significantly reduced DAO, TNF-α, IL-6, IL-1β, LPS, and D-LA levels in the ileum (P<0.01), and upregulated mRNA and protein expressions of Claudin 1, Occludin, ZO-1, and ABCG2, as well as positive staining area and proportion (P<0.01). The 16S rDNA results showed that in the model group, the α-diversity index of the ileal microbiota was increased, and species diversity and richness were enhanced, with microbiota dysfunction observed. The community structure of the gut microbiota was significantly different from that of the normal microbiota. The abundance of probiotics was decreased, and the abundance of pathogenic bacteria was increased, with butyrate-producing bacteria showing a low abundance. In contrast, Simiaowan at all doses reduced species diversity and richness, regulated microbiota dysfunction, and promoted the shift of the structure of the gut microbiota community towards a normal one. This increased the abundance of beneficial bacteria, decreased the abundance of harmful bacteria, and restored the abundance of butyrate-producing bacteria. ConclusionSimiaowan enhances ileal uric acid excretion and further alleviates HUA by modulating the gut microbiota composition to improve the intestinal barrier and upregulate the expression of the urate transporter ABCG2 in HUA rats.
2.WWP1 plays a positive role in ameloblast differentiation and enamel formation in mice
Jingxiao LIN ; Jiaxin NIU ; Jing FU ; Hao FENG ; Yan LIU ; Guohua YUAN ; Zhi CHEN
Chinese Journal of Stomatology 2025;60(1):33-42
Objective:To investigate the role of WW domain containing E3 ubiquitin protein ligase 1 (WWP1) in enamel development of mice.Methods:Single-cell RNA sequencing data of incisor tissues of postnatal day 7 (P7) mice and mandibular first molar tooth germs of P3.5 mice were used to analyze the expression of Wwp1 in dental epithelial cells. Immunohistochemistry was performed to observe the distribution and expression levels of WWP1 in the epithelium of mouse incisors and mandibular first molar tooth germs. Wwp1 knockout (Wwp1 KO) mice were generated and collected with their control littermates at P1, P7, three mice per group, as well as at P14, P28, 2 months (2M), and 3M, six mice per group. The enamel volumes of molars and incisors were analyzed using micro-CT. Scanning electron microscopy was employed to examine the enamel cross-sections of Wwp1 KO and control mice. Energy dispersive spectroscopy (EDS) was used to analyze the calcium and phosphorus content of the enamel rod of incisors. Immunofluorescence was performed to detect the expression of amelogenin (AMELX) in the ameloblasts of Wwp1 KO and control mice. Additionally, LS-8 ameloblast-like epithelial cells were cultured, and Wwp1 siRNA or overexpression plasmids were transfected to knock down or overexpress WWP1. The protein levels of AMELX were then assessed by Western blotting.Results:Single-cell sequencing result showed a high Wwp1 mRNA expression level in the epithelial cells of mouse incisors and mandibular molar tooth germs. Immunohistochemistry revealed the expression of WWP1 in presecretory, secretory, transitional, and mature ameloblasts. Wwp1 KO mice exhibited enamel developmental defects. The enamel volumes of molars and incisors in Wwp1 KO mice [(0.155±0.016), (0.300±0.017) μm 3] were reduced by 23.95% ( P<0.001) and 28.31% ( P<0.001) compared with the control group [(0.203±0.062), (0.418±0.023) μm 3] respectively. Scanning electron microscopy showed disorganized enamel structures in Wwp1 KO incisors and molars. EDS results showed the weight percent of calcium in the enamel rod of incisors decreased in Wwp1 KO mice [(20.74±0.91)%] compared with the control group [(30.30±3.83)%] ( P<0.001), and the calcium-to-phosphorus ratio decreased in Wwp1 KO mice (1.93±0.01) compared with the control group (2.02±0.01) ( P<0.001). Immunofluorescence showed weaker AMELX expression in ameloblasts of mandibular first molar tooth germs from P1 and P7 Wwp1 KO mice compared with the control group ( P<0.001, P<0.001). In LS-8 cells, Wwp1 knocked-down led to a decrease of AMELX protein expression, while WWP1 overexpression resulted in an increased AMELX protein level. Conclusions:WWP1 promotes ameloblast differentiation and enamel matrix mineralization, playing a critical role in enamel formation.
3.Whole genome sequencing and analysis of multidrug resistant ST314 Salmonella Kentucky from a broiler slaughterhouse
Jia-rui LI ; Rui-yuan SUN ; Pei-jie HE ; Hao-tian LIU ; Ru-yi KUANG ; Jing XIA ; Min CUI ; Yong HUANG ; Li-kou ZOU ; Xin-feng HAN
Chinese Journal of Zoonoses 2025;41(5):537-543
This study investigated the potential pathogenicity and genetic characteristics of ST314 Salmonella Kentucky(S.Ken-tucky)isolates from a broiler slaughterhouse.Antimicrobial susceptibility testing and whole-genome sequencing(WGS)were used to determine antimicrobial resistance,virulence factors,and the presence of antimicrobial resistance genes(ARGs)and mobile genetic elements(MGEs)among the isolates.The three multidrug resistant(MDR)isolates exhibited high resistance to multiple antimicrobial agents.The F4-2S strain exhibited resistance to 14 drugs across seven categories,whereas the F4T strain showed resistance to 13 drugs in the same number of categories.In contrast,the Y23 strain was resistant to nine drugs in six categories.Notably,F4-2S dem-onstrated high homology with F4T:both possessed 13 ARGs distributed across nine categories,in addition to a wide range of virulence factors,including secretion systems and effector proteins.The presence of IncR and IncX1 plasmids significantly enhanced both the antimicrobial resistance and pathogenicity of the isolates.The genome map of Y23 revealed a chromosome alongside two plasmids.The chromosome containedonly one resistance gene but several virulence factors,including the type III secretion system(T3SS),which is crucial for bacterial invasion.The plasmid pY23-1 contained eight types of 19 ARGs.Comparative analysis indicated that pY23-1 ex-hibited high homology with pZ1323SSL0055 and pSAL-045,all of which contained multiple ARGs,thus suggesting critical roles of these genes in the evolution of bacterial resistance.In conclusion,ST314 S.Kentucky demonstrated a complex mechanism of resis-tance coupled with significant pathogenic potential.The ARGs and MGEs in the plasmid contributed to the emergence and dissemina-tion of antimicrobial resistance.The multiple virulence factors present in the chromosome may be key factors driving the increasing virulence of ST314 S.Kentucky.
4.Mechanisms and intervention strategies of aging based on epigenetics
Li-yuan ZHANG ; Hao-nan SHI ; Wen-feng ZHANG ; Ming-qian ZHANG ; Zi-yang ZHAO ; Zhen-zhen CHENG ; Ti ZHANG ; Zhen-teng YAN ; Jian-ning SUN ; Shi-fen DONG
Chinese Pharmacological Bulletin 2025;41(12):2230-2235
Aging is comprehensively influenced by multiple fac-tors such as internal genes,cellular metabolism,external envi-ronment,and lifestyle habits.Among them,epigenetic regula-tion plays a core role.Epigenetic modifications,including DNA methylation,histone modification,heterochromatin remodeling,and non-coding RNA regulation,act in concert with the three-di-mensional genome architecture to precisely regulate gene expres-sion.This review elaborates on the factors influencing epigenetic regulation,as well as the mechanisms of how epigenetics affects the occurrence of organismal aging and the corresponding inter-vention strategies,providing relevant insights for uncovering the mechanisms of aging and preventing/treating aging-related disea-ses.
5.In vitro fluorescent substrate assay for the activity of leucine aminopeptidase(LAP)in Echinococcus multilocularis
Jia-yu CHEN ; Yao DAI ; Shun-juan WANG ; Yang XIAO ; Xin-zong YAN ; Tong LIU ; Zhi-hao YUAN ; Kai-li SHI ; Run-le LI ; Feng TANG
Chinese Journal of Zoonoses 2025;41(1):23-31
This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.
6.Long-term efficacy analysis of narrow-margin hepatectomy intraoperative radiotherapy for hepatocellular carcinoma
Mengyuan LI ; Yanling WU ; Liming WANG ; Fan WU ; Shulian WANG ; Yueping LIU ; Yongwen SONG ; Ning LI ; Yuan TANG ; Hao JING ; Hui FANG ; Ningning LU ; Shunan QI ; Zhuanbo YANG ; Siye CHEN ; Yexiong LI ; Jianxiong WU ; Qinfu FENG ; Yirui ZHAI ; Bo CHEN
Cancer Research and Clinic 2025;37(5):343-350
Objective:To investigate the long-term efficacy, safety and prognostic factors of intraoperative radiotherapy (IORT) for narrow-margin (resection margin < 1 cm) hepatectomy in patients with hepatocellular carcinoma (HCC) during radical surgery.Methods:A retrospective cohort study was conducted. The data of primary HCC patients undergoing radical surgery and narrow-margin hepatectomy IORT in the Cancer Hospital of the Chinese Academy of Medical Sciences from November 2009 to February 2019 were collected. IORT applied 6 MeV or 9 MeV electron beams and a single irradiation was given to the margin. Kaplan-Meier method was used for the overall survival (OS) and disease-free survival (DFS) analysis; log-rank test was used for survival comparison among subgroups. The recurrence patterns and adverse reactions were recorded. Univariate and multivariate Cox proportional hazards models were used to analyze the factors influencing the OS and DFS.Results:A total of 64 patients were enrolled, with the median age [ M ( Q1, Q3)] of 57 years (49, 63) years. All patients included 55 males (85.9%) and 9 females (14.1%). The median dose of IORT was 15 Gy (range: 12-17 Gy). The median follow-up time was 83.3 (64.4, 91.9) months. The 1-year, 3-year, 5-year, 7-year, 10-year OS rates were 90.4%, 80.6%, 75.5%, 71.4% and 47.6%, respectively; the 1-year, 3-year, 5-year, 7-year,10-year DFS rates were 77.8%, 68.1%, 59.6%, 57.6% and 38.4%, respectively. Univariate Cox regression analysis indicated that preoperative serum alpha-fetoprotein (AFP) > 400 ng/ml was an independent risk factor for poor OS (> 400 ng/ml vs. ≤ 400 ng/ml: HR = 6.57, 95% CI: 2.16-19.96, P < 0.001), while not the independent influencing factor of poor DFS ( HR = 1.71, 95% CI: 0.65-4.52, P = 0.277). The age ≤ 60 years or not, gender, viral hepatitis or not, American Joint Committee on Cancer stage, tumor diameter (> 5 cm or not), tumor number, degree of tumor differentiation, microvascular invasion or not, microsatellite nodules or not, anatomical liver resection or not, and the dose of IORT ≤15 Gy or not were not the independent influencing factors of poor OS and DFS (all P > 0.05). Kaplan-Meier method analysis showed that patients with preoperative serum AFP ≤ 400 ng/ml (48 cases) had better OS compared with those with preoperative serum AFP>400 ng/ml (16 cases) (5-year OS rate: 84.8% vs. 44.9%; 7-year OS rate: 79.9% vs.37.4%), and the difference was statistically significant ( P = 0.002). There was no statistically significant difference in the DFS between the 2 groups ( P = 0.134). During the follow-up, 28 patients (43.8%) relapsed, including 17 cases (26.6%) of early recurrence and 11 cases (17.2%) of late recurrence. No marginal recurrence was observed. There were 22 cases (34.4%) of intrahepatic recurrence alone, 2 cases (3.1%) of extrahepatic recurrence and 4 cases (6.3%) of stimutaneous recurrence inside and outside the liver. The 1-, 3-, 5- and 7-year cumulative recurrence rates inside the liver were 19.0%, 27.2%, 37.4% and 39.3% respectively, and the cumulative recurrence rates outside the liver were 6.4%, 8.0%, 9.6% and 9.6% respectively. There were no adverse reactions above grade 3 in the entire group. There were no surgery-related deaths within 30 d after the operation, and no radiation-induced liver disease occurred. Conclusions:Narrow-margin IORT helps HCC patients receiving hepatectomy to achieve favorable long-term survival and adverse reactions are tolerable. It can be used as a safe and effective adjuvant therapy alternative.
7.Long-term protective efficacy of recombinant CHO cell-derived hepatitis B vaccine:A 26-year follow-up study in Zhengding county
Qiudong SU ; Zhiyong HAO ; Feng QIU ; Lili QIAO ; Huijuan JIA ; Shuang ZHANG ; Pengpeng YUAN ; Juan CHU ; Zhiyong ZHANG ; Junfang YAO ; Jinling WEI ; Yan WANG ; Peiqi ZHAO ; Yujiao LIU ; Zhao GAO ; Jingchen MA ; Feng WANG ; Haisong ZHOU
Chinese Journal of Experimental and Clinical Virology 2025;39(4):434-440
Objective:To evaluate the long-term protective efficacy of the recombinant Chinese hamster ovary cell-derived hepatitis B vaccine(CHO-HepB)26 years post-vaccination in the rural China.Methods:Zhengding county,Hebei province was designated as a rural monitoring site for CHO-HepB efficacy. Study participants included individuals born between 1997 and 1999 who had completed the three-dose CHO-HepB primary series without booster doses. A cross-sectional survey was conducted in late 2024 using random sampling. Demographic and vaccination history data were collected via questionnaires,and hepatitis B virus(HBV)serological markers were detected using chemiluminescence. Historical surveillance data were integrated to infer infection statuses of HBsAg-positive individuals and evaluate longitudinal trends in anti-HBs seropositivity and antibody titers.Results:Among 178 participants(mean time since vaccination:26.2 years),the seroprevalence rates were 0.6% for HBsAg(95% CI:0.0%-1.6%),64.6% for anti-HBs(95% CI:57.6%-71.6%),and 1.1% for anti-HBc(95% CI:0.0%-2.7%). Compared to the pre-vaccination baseline HBsAg positivity of 11.3% in children under 10 years of age,the estimated vaccine protection rate was 95%. Two notable cases were identified:one with concurrent HBsAg and anti-HBc positivity and one with anti-HBs and anti-HBc positivity,suggestive of transient HBV exposure(1999—2009)without chronicity. Natural immune boosting was inferred for the latter case based on anti-HBs titer dynamics. Longitudinal analysis of four prior cross-sectional surveys(2005,2009,2013,and 2017)revealed no significant upward trends in HBsAg and anti-HBc positivity(both P>0.05)over 26 years,while anti-HBs seropositivity declined significantly( P<0.05)from 6 to 26 years post-vaccination. Conclusion:The CHO-HepB vaccine demonstrates sustained immunological persistence and robust long-term protection up to 26 years post-immunization. Continued emphasis on rigorous implementation of mother-to-child transmission prevention strategies is critical for future hepatitis B control.
8.Clinical observation of enteral nutrition support in pediatric patients after heart transplantation
Chang'e LIU ; Zhe ZHAO ; Aihong LIU ; Yuhan CHEN ; Yun HAO ; Xiaohan YUAN ; Yue MA ; Jiandang LI ; Cong WU ; Yanjuan ZHU ; Gengxu ZHOU ; Zhichun FENG ; Xiaoyang HONG
Chinese Journal of Pediatrics 2025;63(10):1126-1130
Objective:To evaluate the safety and clinical efficacy of enteral nutrition (EN) initiated within 24 h after heart transplantation in pediatric patients.Methods:A retrospective cohort study was conducted. Clinical data from 16 pediatric heart transplant recipients at the Seventh Medical Center of the Chinese People′s Liberation Army General Hospital between October 2022 and October 2024 were collected, including demographics, anthropometric measurements, biochemical markers, cytokine levels, and clinical outcomes. Based on the timing of EN initiation, the patients were divided into EN-initiated within 24 h and EN-initiated after 24 h 2 groups. Demographic data, preoperative extracorporeal membrane oxygenation (ECMO) support, physical examination indicators, laboratory parameters, and cytokine levels were compared between groups using independent samples t-test, Mann-Whitney U test, Fisher′s exact probability test. Results:The cohort comprised 16 patients (10 males and 6 females) with an age of (12.5±1.9) years. The EN-initiated within 24 h group comprised 6 cases, and the EN-initiated after 24 h group comprised 10 cases. No significant difference was observed between the two groups in age, preoperative body mass index Z-score, preoperative ECMO support, physical examination indicators, laboratory parameters (total protein, albumin, hemoglobin), or cytokine levels (all P>0.05). Compared to the EN-initiated after 24 h group, the EN-initiated within 24 h group exhibited a shorter intensive care unit stay ( t=2.65, P<0.05) and shorter mechanical ventilation duration ( t=2.23, P<0.05) than EN-initiated after 24 h group. Total hospitalization length had no significant difference ( P>0.05). At 72 h post-transplant, the EN-initiated within 24 h group had a lower interleukin-12 P70 ( t=2.46, P<0.05) and interferon-γ levels ( t=2.55, P<0.05) than EN-initiated after 24 h group. Prior to discharge, the EN-initiated within 24 h group has a lower mean skinfold thickness ( t=2.49, P<0.05) and lower mid-upper arm circumference ( t=2.36, P<0.05) compared with the EN-initiated after 24 h group. Conclusions:Initiating EN within 24 h postoperatively is safe and feasible in pediatric heart transplant recipients. Early EN may shorten the length of intensive care unit stay and mechanical ventilation while attenuating postoperative release of inflammatory cytokine.
9.Current status of bacterial contamination control and prevention measures and construction of quality control laboratory in Chinese blood stations
Xiaohua YUAN ; Yanbo MIAO ; Feng YAN ; Guoqiang FENG ; Ying LI ; Xiulan HU ; Hao LI ; Yan QIU
Chinese Journal of Nosocomiology 2025;35(13):2034-2039
OBJECTIVE To evaluate the current status of bacterial contamination control and prevention measures and construction of quality control laboratory in Chinese blood station,and find out the problems and put forward the improvement suggestions.METHODS A total of 41 questionnaires were sent out for performance comparison by secretariat of working group of Chinese blood collection and supply institutions from May 2024 to Jun.2024,and 40 questionnaires were received(14 blood centers and 26 central blood stations),39 of which were valid.The questionnaire survey covered four aspects,including disinfection and surveillance,construction of quality control laboratory,sterility test for blood component and monitoring of blood transfusion reactions.The data were pro-cessed through itemized statistics and descriptive analysis.RESULTS Totally 84.62%of the blood stations used io-dine-containing disinfectants for arm disinfection of the blood donors,and the monthly monitoring was the primary frequency.Among the quality control laboratories,43.59%were registered as biosafety level 2,while 35.90%lacked biosafety registration.As for the pressure settings of the laboratories,64.10%were under normal pres-sure,15.38%under negative pressure and 17.95%under positive pressure.In the sterility test,the utilization rate of ultra clean operating tables and biological safety cabinets was 48.72%,the blood stations that did not have the indoor quality control accounted for 79.49%,and only 35.90%participated the external quality assessment.Regarding the approaches to confirm the positive result,25.64%of the blood stations adopted the re-peated tests,and 15.38%adopted the combination with positive culture bottle.The shortage of fund was the ma-jor restricted factor for the sterility test,and the confirmation of positive result was the fundamental difficulty.The blood stations with the feedback of insufficient transfusion reactions reported from hospitals ac-counted for 53.85%,while the blood stations that encountered suspected bacterial transfusion reactions with nega-tive culture results accounted for 25.64%.CONCLUSIONS The infeciton control and prevention measures and the construction of quality control laboratory vary significantly in Chinese blood stations.The incomplete biosafety registration,non-standardized sterility test operation and weak surveillance of blood transfusion reactions are the major existing problems.It is suggested that the investment should be increased to push forward the standardi-zation and complete the laboratory biosafety system,and a hospital-blood station closed loop coordination mecha-nism should be established so as to raise the blood safety.
10.In vitro fluorescent substrate assay for the activity of leucine aminopeptidase(LAP)in Echinococcus multilocularis
Jia-yu CHEN ; Yao DAI ; Shun-juan WANG ; Yang XIAO ; Xin-zong YAN ; Tong LIU ; Zhi-hao YUAN ; Kai-li SHI ; Run-le LI ; Feng TANG
Chinese Journal of Zoonoses 2025;41(1):23-31
This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

Result Analysis
Print
Save
E-mail