1.The Regulatory Effects and Mechanisms of Piezo1 Channel on Chondrocytes and Bone Metabolic Dysregulation in Osteoarthritis
Yan LI ; Tao LIU ; Yu-Biao GU ; Hui-Qing TIAN ; Lei ZHANG ; Bi-Hui BAI ; Zhi-Jun HE ; Wen CHEN ; Jin-Peng LI ; Fei LI
Progress in Biochemistry and Biophysics 2026;53(3):564-576
Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca2+, K+, and Na+, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca2+ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca2+ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca2+ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.
2.Engineered Bacteriophages for The Treatment of Multidrug-resistant Bacterial Infections
Yu-Ying CHEN ; Chun-Mei HUANG ; Jin-Zhi PAN ; De-Liang LIU ; Yang ZHOU ; Gui-Qin DAI ; Peng-Fei ZHAO ; Hong-Zhou LU ; Ming-Bin ZHENG
Progress in Biochemistry and Biophysics 2026;53(6):1581-1596
Multidrug-resistant (MDR) bacterial infections have emerged as a serious challenge of global public health crisis. The overuse and misuse of conventional antibiotics have dramatically accelerated the emergence, evolution and worldwide spread of drug-resistant bacterial strains, necessitating urgent exploration of novel antibacterial strategies. Bacteriophages serve as natural bacterial predators offering distinct advantages including high host specificity, autonomous self-replication capabilities and cost-effective large-scale production. However, wild-type phages present significant clinical limitations due to their narrow host ranges, susceptibility to rapid immune clearance and poor penetration of bacterial biofilms, which severely restrict their therapeutic applications. The convergence of synthetic biology, nanotechnology and advanced gene editing technologies has accelerated the development of engineered bacteriophage platforms, providing programmable, scalable and clinically translatable pathways to overcome these inherent biological constraints. Here, we systematically delineate four fundamental strategies for engineered bacteriophage development. Chemical modification utilizes reactive functional groups such as amino, carboxyl and thiol moieties on capsid proteins through esterification, amidation or click chemistry reactions to achieve precise drug conjugation and surface functionalization. In vivo editing encompasses ultraviolet or chemical mutagenesis for random mutation induction, homologous recombination for targeted genetic alterations, recombineering methodologies including electroporation-mediated bacteriophage recombination engineering, and CRISPR-Cas systems for precise genome editing to enable exact genetic reconstruction and host range reprogramming. In vitro synthesis leverages genome engineering platforms where intact phage genomes are transferred into yeast or host bacteria to facilitate highly efficient homologous recombination, enabling large DNA fragment assembly and cross-gene host range expansion without bacterial toxicity constraints. Directed evolution combines artificial selection through mutation library screening with rational design approaches involving chimeric receptor binding protein construction or site-specific mutagenesis, effectively balancing the discovery of unknown adaptive pathways with targeted host specificity modification. Moreover, we comprehensively discuss therapeutic applications across diverse clinical scenarios. Engineered bacteriophage effectively disrupt bacterial biofilms through sophisticated functionalized delivery platforms including nanozyme-conjugated phages, phage-liposome nanoconjugates and bio-responsive hydrogels, demonstrating significantly enhanced bactericidal efficiency compared to unmodified free phages. These bioengineered vectors attenuate bacterial virulence and resensitize pathogens to antibiotics by delivering CRISPR-Cas systems or base editors to disrupt critical virulence factors such as pili, capsule synthesis machineries and quorum sensing systems, or by inactivating antibiotic resistance determinants including beta-lactamase genes. As an intelligent nanomedicine delivery platform, engineered bacteriophage enable precise pathogen elimination an through photocatalytic reactive oxygen species generation, immunomodulatory interventions, or controlled release of antibacterial drugs. Furthermore, oral administration of engineered bacteriophage facilitates microbiota modulation, which selectively eliminate intestinal pathogens while preserve beneficial commensal microbiota, thereby restoring microbial community balance and preventing complications associated with dysbiosis. Finally, we critically analyze persistent challenges including host strain matching complexity, evolution of bacterial resistance mechanisms, pharmacokinetic optimization requirements, optimal administration route selection, large-scale production quality control standards and clinical dosing determination protocols. Through multidisciplinary integration of synthetic biology, infectious disease medicine and immunology, future translational medicine studies of bacteriophage should establish comprehensive technical platforms encompassing rapid phage screening, intelligent rational design, rigorous in vivo evaluation and standardized clinical validation processes, ultimately advancing engineered bacteriophage from laboratory innovations to clinically approved therapeutics for effectively combating MDR bacterial infections.
3.Differences in deltamethrin resistance and kdr gene mutation in Culex tritaeniorhynchus population in and outside the Yellow Sea wetland
Xiao-er ZHANG ; Zhi-ming WU ; Ye TIAN ; Qian CUI ; Yu-qian JI ; Huan WANG ; Shu-juan YANG ; Yi-chao ZHAO ; Yu WANG ; Hua-yu YIN ; Yu DING ; Guo-jin YAN ; Min-sen ZHAO ; Shou-gang ZHANG ; Bing-dong SONG ; Hong-na CHEN ; Jian GAO ; Wei-fang YANG ; Yu-fu ZHANG ; Hui LIU ; Hong-liang CHU
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):101-107
Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.
4.Qualitative study on factors influencing the health of courier/food delivery workers based on the social-ecological model
Ruina LI ; Jingjing DU ; Jin WANG ; Xiaoman LIU ; Yan YE ; Yan YIN ; Zhi WANG ; Fengqiong CHEN ; Huanqiang WANG ; Shuang LI
China Occupational Medicine 2026;53(2):144-149
Objective To explore the health issues and influencing factors of workers in new forms of employment, represented by couriers and food delivery workers, based on the social-ecological model (SEM). Methods A total of 44 couriers and food delivery workers from Beijing City, Shanghai City, Guangzhou City, and Chongqing City were recruited as the study subjects using purposive sampling combined with snowball sampling method. An interview guide was developed based on the SEM to conduct semi-structured interviews. Thematic analysis was employed to code and analyze the interview data. Results The health influencing factors among the couriers and food delivery workers based on the SEM included three first-level themes at the micro-, meso-, and macro-levels, namely "individual factors," "occupational environmental factors," and "social environmental factors," each comprising three second-level themes. At the micro-level, individual factors such as insufficient health literacy, unhealthy lifestyles and behaviors, and sustained psychological burden jointly contributed to the health vulnerability among these couriers and food delivery workers. At the meso-level, occupational environmental factors including algorithmic management, high-load work environments, and inadequate interpersonal support, jointly construct a high-pressure and high-intensity work pattern. At the macro-level, social environmental factors such as insufficient social security caused by the de facto nature of labor relations, economic pressure resulting from unstable income in the market environment, and psychological depletion caused by occupational discrimination further exacerbate the health vulnerability among these workers. Conclusion The health issues of the couriers and food delivery workers result from the interplay of factors across micro-, meso-, and macro- levels. Therefore, a multi-level collaborative health protection system involving individuals, organizations, and society should be established to improve their health status.
5.Clinical Observation on Treatment of Hip Joint Pain with Mailuoning Compound Solution via Nerve Blocks around Hip Joint
Tao JIN ; Fuchang MA ; Cheng HUANG ; Manxia ZHI ; Ming YA
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(8):152-158
ObjectiveTo observe the clinical efficacy and safety of Mailuoning compound solution in the treatment of hip joint pain via nerve blocks around the hip joint. MethodsFrom March 2015 to March 2019,a total of 136 patients with hip joint pain who met the inclusion criteria were admitted and divided into an observation group and a control group according to the random number table method. Among them,six cases fell off due to failure to complete five treatments,and finally, 130 patients entered clinical observation,with 65 cases in each group. The observation group used Mailuoning compound solution for nerve blocks around the hip joint(including obturator nerve,femoral nerve branch,superior gluteal nerve, and hip fascia). The control used Mailuoning compound solution for a simple obturator nerve block. The differences in the visual analogue scale (VAS) and Harris score of hip joint of the two groups before and after treatment were observed. Any adverse drug reactions and adverse events during the treatment of the patients were recorded. ResultsThe VAS score of the two groups was significantly decreased after treatment (P<0.01). The observation group had a more significant decrease compared to the control group(P<0.01). The total Harris score of hip joint, pain degree,function score, and motion of joint of the two groups were significantly improved after treatment (P<0.01). Compared with the control group,the improvement in the total Harris score of hip joint, pain degree,and function score was more significant in the observation group (P<0.01). The clinical efficacy based on the Harris score of hip joint of the two groups was compared. The excellent and good rate of the observation group was 84.62% (55/65), which was significantly better than that of the control group [56.92% (37/65)] (χ2=12.05,P<0.01). The follow-up results showed that the patients who achieved excellent and good results had stable curative effects and low recurrence rates,and there was no significant difference in recurrence rate between the two groups. Case analysis showed that after treatment of femoral head necrosis,the saccular transparent shadow of the femoral head was significantly reduced,and the number of bone trabeculae increased. The low-density shadow decreased as can be seen on hip X-rays. In patients with hip osteoporosis after treatment,the number of bone trabeculae increased, and the low density shadow reduced. ConclusionThe use of Mailuoning compound solution for nerve blocks around the hip joint gives full play to the synergistic effect of Mailuoning compound solution and nerve block. It can effectively relieve hip joint pain,promote the recovery of hip joint function,reduce the disability rate,and improve the quality of life of patients. Early intervention is an important link in the treatment of hip joint pain diseases,which can effectively control the development of the patient's disease. Mailuoning compound solution is a new idea and method to treat hip joint pain through neuroregulation,which is easy to operate,with high safety and good therapeutic effect. In future studies,a larger sample size is needed,and more in-depth research should be conducted on the imaging changes and mechanisms of action for various hip joint pain diseases.
6.The study on the correlation between cognitive impairment of cerebral small vessel disease and white matter hyperintensity grade and cerebral atrophy grade
Ting LIU ; Jin ZHI ; Zhongzhong LIU ; Fang WANG ; Fengzhu MENG ; Xuemei LIN ; Yan WANG
Journal of Practical Radiology 2025;41(1):1-4
Objective To investigate the correlation between cognitive impairment of cerebral small vessel disease(CSVD)and white matter hyperintensity grade and cerebral atrophy grade.Methods The data of 213 patients with CSVD were analyzed retro-spectively.The semi-quantitative Fazekas visual score of brain MR was used to evaluate the white matter hyperintensity,and cerebral atrophy was evaluated by the whole cerebral cortex atrophy grade.Mini-mental state examination(MMSE)and Montreal cognitive assessment(Mo CA)were used to evaluate each patient and to classify according to the results.Results There was a statistically sig-nificant difference in age between male and female patients with CSVD(P=0.04,t=4.288).The mean age of males[(66.5±10.3)years]was less than females[(69.5±10.0)years].There was significant difference between patients with different gender and history of hypertension(P=0.02,t=5.424).There were statistical differences between white matter hyperintensity Fazekes grade and MMSE and Mo CA scores(P<0.001,χ2=5.639;P<0.001,χ2=5.843),and there were statistical differences between whole cerebral cortex atrophy grade and MMSE score(P=0.036,χ2=2.895).Conclusion There is a certain correlation between cognitive impairment of CSVD and head MR imaging evaluation grade.
7.OBE-based Design of Biochemistry Teaching:Taking the Teaching of"Classification and Specificity of Enzymes"as an Example
Hua HAI ; Li-Yan NA ; Ming-Lei HE ; Hong-Ze YANG ; Li-Ming JIN ; Chun-Bin LI ; Hua JIN ; Quan ZHOU ; De-Fu ZHI
Chinese Journal of Biochemistry and Molecular Biology 2025;41(6):903-913
Biochemistry,as a fundamental course for science and engineering majors related to biology and chemistry,holds a significant position in the curriculum.The course team at Dalian Minzu University is committed to teaching innovation,adopting the outcome-based education(OBE)concept for teaching de-sign and incorporating ideological and political elements,in order to achieve the dual goals of knowledge transmission and value guidance.The team has established a three-dimensional teaching goal of"knowl-edge,morality,and ability",covering"consolidating core knowledge,cultivating moral sentiment,and enhancing innovation ability".Through a multi-dimensional integrated teaching method of"three integra-tions and five combinations",multiple rounds of teaching practice have been carried out in the applied chemistry major using"classification and specificity of enzyme"as an example.The output of teaching re-sults and survey questionnaires show that students highly recognize the teaching design and its"process-based learning"evaluation method,fully reflecting the student-centered teaching idea.Research has shown that OBE design combined with ideological and political elements can effectively promote students' knowl-edge acquisition,moral growth,and innovation ability improvement in the course of Biochemistry.This teaching design not only helps students construct correct worldviews,outlooks on life,and values,but also significantly enhances their innovative thinking and practical abilities.This teaching design can not only ef-fectively improve the teaching quality of the course,but also provide new perspectives and ideas for the teaching design of Biochemistry,realizing the organic integration of professional knowledge imparting and i-deological and political education,and has certain innovation and practical significance.
8.Correlation of characteristics of symptomatic middle cerebral artery plaques with risk of stroke recurrence:Study based on high-resolution vessel wall imaging
Xing-xing ZENG ; Li-rong WANG ; Zhi-guo GAO ; Jin-fei LU ; Xiao-li JIANG ; Xiao-yi LI
Chinese Medical Equipment Journal 2025;46(2):63-67
Objective To investigate the correlation of the characteristics of symptomatic middle cerebral artery plaques with the risk of stroke recurrence based on high-resolution vessel wall imaging(HR-VWI).Methods Totally 83 patients hospitalized for acute ischemic stroke(AIS)and transient ischemic attack(TIA)at Jingmen People's Hospital and Yichang Central People's Hospital from January 2019 to August 2022 were selected prospectively,who all underwent the treatment with antiplatelet aggregation and intensive lipid lowering by statins.During the follow-up,AIS or TIA recurrences were determined in case of newly found symptoms of neurological impairment in the same supply area of the responsible vessel or new infarct foci confirmed by cranial diffusion weighted imaging(DWI).The patients with AIS or TIA recurrences were enrolled into a recurrence group,and the remained ones were divided into a non-recurrence group.The recurrence group went through HR-VWI scanning within two weeks of recurrence and statin treatment,and the non-recurrence group was examined with HR-VWI half a year after receiving statin treatment.All the patients had their clinical indexes compared before and after statin treatment,the baseline data of the two groups underwent univariate analysis,and Logistic regression analysis was performed for the high-risk factors related to recurrence.SPSS 22.0 software was used for statistical analysis.Results After six months of statin treatment,all the patients were improved in TC,TG,luminal stenosis rate,high T1WI signal,plaque burden,plaque enhancement rate and NIHSS score,with the differences being significant(all P<0.05).Univariate analysis showed the recurrence group had higher plaque enhancement rates(P=0.012)and higher plaque burden(P=0.047)when compared with the non-recurrence group,with the differences being significant;the two groups were not statistically different in luminal stenosis rate,high T1WI signal,plaque thickness and remodeling index(all P>0.05).Multivariate logistic regression analysis indicated the plaque enhancement rate was independently correlated with stroke recurrence within 6 months(P=0.027).Conclusion HR-VWI can effectively assess MCA plaque characteristics in recurrent stroke patients,and high plaque enhancement rate faciliates the evaluation of stroke recurrence.[Chinese Medical Equipment Journal,2025,46(2):63-67]
9.Clinicopathological analysis of 15 cases of primary cardiac tumors in children
Wenting WANG ; Zhi LI ; Lian CHEN ; Bin ZHANG ; Jing JIN
Chinese Journal of Clinical and Experimental Pathology 2025;41(6):765-770
Purpose To explore the clinical and pathological characteristics of primary benign,borderline,and malignant cardiac tumors in children.Methods 15 cases of primary cardiac tumors in children were collected,and their clinical manifestations,pathological morphology,and immunophenotypes were analyzed.Relevant literature was also reviewed.Results The age of 15 patients ranged from 0.3 to 12 years old,with an average age of about 5 years and a median age of 2 years.9 cases were males and 6 cases were females.4 cases were found to have heart masses during physical examination,3 cases were treated for symptoms of cerebral infarction,1 case was treated for limb weak-ness,1 case was treated for systemic edema,1 case was treated for accelerated heartbeat,1 case was treated for cough,1 case was treated for pneumonia,1 case was treated for abdominal pain,1 case was treated for vomiting,and 1 case was treated for fever and shortness of breath.Echocardiography showed 8 cases occurring in the left heart system(6 in the left atrium and 2 in the left ventricle),4 cases occurring in the right heart system(2 in the right atrium and 2 in the right ventricle),2 cases occurring in the pericardium,and 1 case occurring in the interventricular septum.Ac-cording to pathological diagnosis,13 cases were benign tumors(8 cases of mucinous tumors,4 cases of rhabdomyo-mas,and 1 case of fibroma),1 case was a malignant tumor(embryonal rhabdomyosarcoma),and 1 case was a border-line tumor(NTRK rearranged spindle cell tumor).Conclusion Primary cardiac tumors in children are relatively rare,and borderline and malignant tumors are even rarer.The types of common tumors are different from those in a-dults,and they are prone to misdiagnosis due to non-specific clinical symptoms.For specific cardiac tumors,it is rec-ommended to conduct genetic testing when necessary based on clinical manifestations to further investigate the possibili-ty of related syndromes.
10.Assay for detection of toxigenic Clostridioides difficile with combined microfluidic chip and immunochromatography technology
Hong-rui CHENG ; Xiao-jun SONG ; Yu CHEN ; Meng ZHANG ; Meng-ting CAI ; Kun ZHU ; Yu-lei TAI ; Shi-bo YING ; Da-zhi JIN
Chinese Journal of Zoonoses 2025;41(2):142-149
An assay was established for detection of toxigenic Clostridioides difficile by combining microfluidic chip analysis with immunochromatography,and its performance was evaluated and compared with those of the Xpert C.difficile/Epi and VIDAS CD AB tests.Primer pairs were designed according to the tcdB and tpi genes in C.difficile.The specificity,limit of detection,reproducibility,and stability were evaluated.A total of 215 stool samples from patients with diarrhea were collected and tested in parallel with the Xpert C.difficile/Epi,VIDAS CDAB,and our assay.C.difficile was isolated from samples,and the tcdB gene was identified when discrepant results were obtained from the three above assays.Our assay showed no cross-reaction with other diarrhea-associated pathogens.Its reproducibility was 100%in testing of two standard plasmids containing tcdB and tpi genes at two concentrations(105 and 102 copies/μL).Two standard plasmids were detected after the PCR and immunochromatography reagents had been stored for 3,6,9,and 12 months,and all the results were posi-tive.The limit of detection was 10 copies/μL for toxigenic C.difficile.Testing of 33 samples positive for C.difficile with our assay(33/215,15.3%)yielded findings statistically coherent with those of the Xpert C.difficile/Epi test(kappa value=0.965).The sensitivity,specificity,positive predictive value,and negative predictive value of our assay,with respect to Xpert C.difficile/Epi as the standard,were 94.3%,100.0%,100.0%,and 98.9%;these values were significantly higher than those of VIDAS CDAB(60.0%,98.9%,91.3%,and 92.7%)(Kappa=0.714,OR=157.50,95%CI:62.03-847.28,P=0.013).In conclusion,our newly developed assay is specific,stable,and reproducible,and may be used for rapid and accu-rate detection of toxigenic C.difficile.The assay could be used for C.difficile infection screening in outpatient and emergen-cy,community medical service center,and epidemiological settings.


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