ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.

ObjectiveTo observe the effect of heat-sensitive moxibustion on quality of life and immune function in non-small cell lung cancer （NSCLC） patients undergoing chemotherapy. MethodsSeventy NSCLC patients with qi deficiency and phlegm stasis syndrome were randomly divided into an intervention group and a control group， with 35 cases in each group. The control group received chemotherapy combined with routine symptomatic treatment， while the intervention group additionally received heat-sensitive moxibustion since the first day of chemotherapy. Acupoints included Dazhui （GV14）， bilateral Feishu （BL13）， Zhongwan （CV12）， Qihai （CV6）， and Guanyuan （CV4）. The site exhibiting the strongest heat-sensitization response was selected for moxibustion. Treatment was administered for 45 minutes per session， three times weekly for three consecutive weeks， totaling nine sessions. Before and after treatment， quality of life was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire （EORTC QLQ-C30）， and traditional Chinese medicine （TCM） syndrome scores were evaluated. Peripheral blood levels of natural killer （NK） cells and T-lymphocyte subsets including CD3⁺， CD4⁺， and CD8⁺， and CD4⁺/CD8⁺ ratio were measured. Levels of programmed cell death protein-1 （PD-1）， including PD-1⁺CD4⁺ and PD-1⁺CD8⁺ cells， were also assessed. Liver and renal function were monitored before and after treatment， and adverse events were recorded. ResultsIn the intervention group， 1 participant withdrew and 1 was excluded， while in the control group， 2 participants withdrew. Ultimately， 33 participants in each group were included in the final analysis. The intervention group showed significant improvements in physical， role， emotional， cognitive， and social functioning， as well as global health status after treatment， while scores for fatigue， nausea and vomiting， dyspnea， appetite loss， diarrhea， and TCM syndrome scale were significantly decreased （P＜0.05）. Moreover， the intervention group demonstrated higher scores in physical functioning， role functioning， and global health status， as well as lower scores for fatigue， nausea and vomiting， dyspnea， appetite loss， diarrhea， and the TCM syndrome scale than the control group （P＜0.05）. After treatment， the levels of peripheral NK cells and PD-1⁺CD8⁺ T cells in the intervention group increased significantly； furthermore， the intervention group exhibited higher peripheral NK cell levels and lower PD-1⁺CD8⁺ T cell levels than the control group （P＜0.05）. No significant differences were found in liver or renal function between the two groups （P＞0.05）. In addition， no adverse events such as burns or moxibustion-induced syncope occurred during the study. ConclusionHeat-sensitive moxibustion as an adjunctive therapy may enhance immune function， alleviate clinical symptoms， and improve quality of life， while demonstrating a favorable safety profile in NSCLC patients with qi deficiency and phlegm stasis.

Tumor drug resistance is an important problem in the failure of chemotherapy and targeted drug therapy, which is a complex process involving chromatin remodeling. SWI/SNF is one of the most studied ATP-dependent chromatin remodeling complexes in tumorigenesis, which plays an important role in the coordination of chromatin structural stability, gene expression, and post-translation modification. However, its mechanism in tumor drug resistance has not been systematically combed. SWI/SNF can be divided into 3 types according to its subunit composition: BAF, PBAF, and ncBAF. These 3 subtypes all contain two mutually exclusive ATPase catalytic subunits (SMARCA2 or SMARCA4), core subunits (SMARCC1 and SMARCD1), and regulatory subunits (ARID1A, PBRM1, and ACTB, etc.), which can control gene expression by regulating chromatin structure. The change of SWI/SNF complex subunits is one of the important factors of tumor drug resistance and progress. SMARCA4 and ARID1A are the most widely studied subunits in tumor drug resistance. Low expression of SMARCA4 can lead to the deletion of the transcription inhibitor of the BCL2L1 gene in mantle cell lymphoma, which will result in transcription up-regulation and significant resistance to the combination therapy of ibrutinib and venetoclax. Low expression of SMARCA4 and high expression of SMARCA2 can activate the FGFR1-pERK1/2 signaling pathway in ovarian high-grade serous carcinoma cells, which induces the overexpression of anti-apoptosis gene BCL2 and results in carboplatin resistance. SMARCA4 deletion can up-regulate epithelial-mesenchymal transition (EMT) by activating YAP1 gene expression in triple-negative breast cancer. It can also reduce the expression of Ca²⁺ channel IP3R3 in ovarian and lung cancer, resulting in the transfer of Ca²⁺ needed to induce apoptosis from endoplasmic reticulum to mitochondria damage. Thus, these two tumors are resistant to cisplatin. It has been found that verteporfin can overcome the drug resistance induced by SMARCA4 deletion. However, this inhibitor has not been applied in clinical practice. Therefore, it is a promising research direction to develop SWI/SNF ATPase targeted drugs with high oral bioavailability to treat patients with tumor resistance induced by low expression or deletion of SMARCA4. ARID1A deletion can activate the expression of ANXA1 protein in HER2+ breast cancer cells or down-regulate the expression of progesterone receptor B protein in endometrial cancer cells. The drug resistance of these two tumor cells to trastuzumab or progesterone is induced by activating AKT pathway. ARID1A deletion in ovarian cancer can increase the expression of MRP2 protein and make it resistant to carboplatin and paclitaxel. ARID1A deletion also can up-regulate the phosphorylation levels of EGFR, ErbB2, and RAF1 oncogene proteins.The ErbB and VEGF pathway are activated and EMT is increased. As a result, lung adenocarcinoma is resistant to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Although great progress has been made in the research on the mechanism of SWI/SNF complex inducing tumor drug resistance, most of the research is still at the protein level. It is necessary to comprehensively and deeply explore the detailed mechanism of drug resistance from gene, transcription, protein, and metabolite levels by using multi-omics techniques, which can provide sufficient theoretical basis for the diagnosis and treatment of poor tumor prognosis caused by mutation or abnormal expression of SWI/SNF subunits in clinical practice.

BACKGROUND:Human periodontal stem cells have a certain inhibitory effect on the pro-inflammatory function of M1-type macrophages,and it is not clear whether icariin,which has anti-inflammatory and other pharmacological activities,can enhance the inhibitory effect of human periodontal stem cells on M1-type macrophages. OBJECTIVE:To investigate the effect of icariin on M1 macrophages after pretreatment of human periodontal stem cells. METHODS:Primary human periodontal stem cells were isolated,cultured and characterized.THP-1 was induced and M1-type macrophages were identified by immunofluorescence staining and PCR.Human periodontal stem cells were cultured with α-MEM complete medium containing concentrations of 10-7,10-6,10-5,and 10-4 mol/L icariin,and the cytotoxicity of Icariin on human periodontal stem cells was detected by the CCK-8 assay at 1,3,5,and 7 days,respectively.α-MEM complete medium,untreated α-MEM conditioned medium for human periodontal stem cells and α-MEM conditioned medium for human periodontal stem cells pretreated with icariin for 24 hours were conditioned with RPMI-1640 complete medium in a 1:1 ratio for M1-type macrophages in the control,untreated,and pretreated groups,and 24 hours later,the mRNA expression of inflammatory factors in M1 macrophages was detected by RT-PCR.The protein expression of inflammatory factors in M1 macrophages was detected by ELISA.The expression of surface markers and nuclear factor-κB pathway-related proteins in M1/M2 macrophages was detected by western blot assay. RESULTS AND CONCLUSION:(1)CCK-8 assay results showed that 10-7,10-6,10-5,10-4 mol/L icariin was not cytotoxic to the human periodontal stem cells,and from day 5 onwards,all the concentrations increased the cell viability,and promoted the cell proliferation.10-4 mol/L icariin was selected for follow-up experiment.(2)RT-PCR and ELISA results showed that compared with the control group,the untreated group and the pretreated group both decreased the expression and secretion of interleukin-1β,interleukin-6,and tumor necrosis factor-α of M1-type macrophages(P<0.05),and the pretreated group was lower than the untreated group(P<0.05).(3)Western blot assay results showed that compared with the untreated group,the expression of CD86 was significantly lower in the pretreated group(P<0.05);compared with the control group,the expression of CD206,a surface marker of M2-type macrophages,was elevated in both the untreated and pretreated groups(P<0.01),and it was significantly higher in the pretreated group than in the untreated group(P<0.01).In M1-type macrophages after 24 hours of conditioned culture,compared with the control group,the expression of nuclear factor-κB/P65 was decreased in the untreated group and the pretreated group(P<0.01),and the expression of p-IκBα was decreased only in the pretreated group(P<0.01);the expression of both nuclear factor-κB/P65 and p-IκBα was significantly reduced in the pretreated group compared with the untreated group(P<0.05),while the difference of IκBα in the three groups was not statistically significant.(4)These results indicated that icariin enhanced the inhibitory effect of human periodontal stem cells on M1-type macrophages,and this effect may be related to the inhibition of the nuclear factor-κB signaling pathway of macrophages.

ObjectiveTo study the mechanism of compound Xishu granules （CXG） in inhibiting the proliferation of hepatocellular carcinoma cells by regulating ferroptosis. MethodsThe transplanted tumor model of human Huh7 was established with nude mice and the successfully modeled mice were randomized into model， Fufang Banmao （0.21 g·kg^-1）， low-dose （1.87 g·kg^-1） CXG， medium-dose （3.74 g·kg^-1） CXG， and high-dose （7.49 g·kg^-1） CXG groups. Mice were administrated with drinking water or CXG for 28 days， and the body weight and tumor volume were measured every 4 days. Hematoxylin-eosin staining was employed to observe the histopathological changes of tumors. The cell-counting kit-8 （CCK-8） was used to examine the survival rate of Huh7 cells treated with different concentrations （0， 31.25， 62.5， 125， 250， 500， 1 000 mg·L^-1） of CXG for 24 h and 48 h. CA-AM， DCFH-DA， and C11-BODIPY^581/591 fluorescent probes were used to determine the intracellular levels of ferrous ion （Fe²⁺）， reactive oxygen species （ROS）， and lipid peroxide （LPO）， respectively. The colorimetric method was employed to measure the levels of glutathione （GSH） and superoxide dismutase （SOD）. Western blot was employed to determine the protein levels of glutathione peroxidase 4 （GPX4）， transferrin receptor 1 （TFR1）， and ferritin heavy chain 1 （FTH1）， respectively. ResultsIn the animal experiment， compared with the model group， the drug treatment groups showed reductions in the tumor volume from day 12 （P<0.01）. After treatment， the Fufang Banmao and low-， medium-， and high-dose CXG groups had lower tumor volume， relative tumor volume， and tumor weight than the model group （P<0.05）， with tumor inhibition rates of 48.99%， 79.93%， 91.38%， and 97.36%， respectively. Moreover， the CXG groups had lower tumor volume and relative tumor volume （P<0.05 in all the three dose groups） and lower tumor weight （P<0.05 in medium-dose and high-dose groups） than the Fufang Banmao group. Compared with the model group， the drug treatment groups showed reduced number of tumor cells， necrotic foci with karyopyknosis， nuclear fragmentation， and nucleolysis， and the high-dose CXG group showed an increase in the proportion of interstitial fibroblasts. In the cell experiment， compared with the blank group， CXG reduced the survival rate of Huh7 cells in a dose-dependent manner after incubation for 24 h and 48 h （P<0.05）. Compared with the blank group， the RSL3 group and the low-， medium-， and high-dose CXG groups showed a decrease in the relative fluorescence intensity of CA-AM and increases in the fluorescence intensity of DCFH-DA and fluorescence ratio of C11-BODIPY^581/591， which indicated elevations in the levels of Fe²⁺ （P<0.01）， ROS （P<0.05）， and LPO （P<0.01）， respectively. Compared with the blank group， the RSL3 and low-， medium-， and high-dose CXG groups showed lowered levels of GSH and SOD （P<0.05）. In addition， the RSL3 group and the medium- and high-dose CXG groups showed down-regulated expression of GPX4 and FTH1 （P<0.05）， and the low- and high-dose CXG groups presented up-regulated expression of TFR1 （P<0.05）. ConclusionCXG suppresses the proliferation of hepatocellular carcinoma cells by inducing ferroptosis via downregulating the GSH-GPX4 signaling axis and increasing intracellular Fe²⁺and LPO levels.

Objective:To construct a communication skills assessment scale for newly employed nurses, verify the reliability and validity of the scale in a simulated setting, and develop and construct an effective and structured assessment tool for the communication skills of newly employed nurses.Methods:The Chinese version of the Liverpool Communication Skills Assessment Scale was modified and two rounds of expert consultation were conducted to construct the communication skills assessment scale for newly employed nurses. A total of 194 newly employed nurses at a tertiary hospital between 2024 and 2025 were selected using convenience sampling. Data were collected using a teacher-based evaluation method during simulated communication scenarios. The performance of the nurses was scored, and the reliability and validity of the scale were analyzed.Results:The final version of the scale consisted of 4 dimensions and 11 items, and can be used in both workplace-based and simulation-based evaluations. The expert authority coefficients of both rounds were greater than 0.70. The Kendall's W coordination coefficients for the two rounds of consultation were 0.278 and 0.309 for workplace-based evaluations and 0.256 and 0.295 for simulation-based evaluations. The coefficients of variation for the 11 items in both application scenarios were <0.250. The total Cronbach's alpha coefficient of the scale was 0.805 and the total split-half reliability coefficient was 0.814. In the two application scenarios, the item-level content validity index ranged from 0.769 to 1.000 (all >0.750). The scale-level content validity index was 0.916 and 0.909 (>0.900), respectively, in the workplace-based and simulation-based evaluations. The exploratory factor analysis extracted a total of four common factors, with a cumulative variance contribution of 69.09%, and all item loadings on their corresponding factors exceeded 0.500. Conclusions:The communication skills assessment scale for newly employed nurses has moderate and validated content and number of items. The scale demonstrates high reliability and validity in simulation-based evaluations, and can be used as an effective tool for assessing the communication skills of newly employed nurses.

BACKGROUND:Acupotomy is an effective method for the treatment of cervical spondylosis with definite clinical efficacy,but its key molecular mechanism is still unclear.OBJECTIVE:To observe the effect of acupotomy intervention on the expression of fibroblast growth factor family and kinase insert domain protein receptor in the splenius capitis muscles of rats with cervical spondylosis,and to study the therapeutic mechanism of acupotomy in cervical spondylosis.METHODS:The Genomics Expression Omnibus Database was searched to obtain the microarray dataset GSE153761,which was compatible with the study,and a bioinformatics approach was used for the initial screening of targets,followed by animal experiments.Twenty-four 6-month-old SPF grade Sprague-Dawley rats were randomly divided into four groups.The model of cervical spondylosis was established by unbalanced dynamic and static forces in the model and acupotomy groups.The muscles and ligaments were not cut in the sham operation group.After successful modeling,acupotomy intervention was performed in the acupotomy group,once a week,3 times in total.Normal rats were selected as controls.The posteroanterior and lateral X-rays of the cervical spine were taken for modeling verification;the open-field tests were performed in all rats to observe behavioral changes;the pathological structure of the splenius capitis muscles was observed by hematoxylin-eosin staining;the mRNA and protein expression of fibroblast growth factor family and kinase insert domain protein receptor in the splenius capitis muscles was detected by fluorescent quantitative PCR and immunohistochemical method,respectively.RESULTS AND CONCLUSION:Bioinformatics results indicated that fibroblast growth factor family/kinase insert domain protein receptor is an important signal axis for activating the phosphatidylinositol 3-kinase/protein kinase B signaling pathway.After modeling,the intervertebral space of the rats was narrowed,and the anterior and posterior borders of the vertebral body and the articular process were hyperosteogenous.In the open-field tests,the total distance and average speed in the model group were decreased after modeling(P<0.05),while the total rest time in the model group was increased(P<0.05).After treatment,the total distance and average speed in the acupotomy group were greater than those in the model group(P<0.05),while the total rest time in the acupotomy group was shorter than that in the model group(P<0.05).The pathological changes of the splenius capitis muscles indicated damage to the cervical muscle,and acupotomy improved cervical muscle strain.Compared with the normal group,The mRNA and protein expressions of fibroblast growth factor 7,fibroblast growth factor 9,fibroblast growth factor 10,fibroblast growth factor 18,and kinase insert domain protein receptor in the splenius capitis muscles were increased in the model group compared with the normal group(P<0.05).In contrast,acupotomy treatment could downregulate the above indicators(P<0.05).Thus,acupotomy may repair cervical muscle strain by regulating the expression of fibroblast growth factor 7,fibroblast growth factor 9,fibroblast growth factor 10,fibroblast growth factor 18,and kinase insert domain protein receptor,thereby improving intervertebral disc degeneration,which may be the key target for acupotomy treatment of cervical spondylosis.

BACKGROUND:There are many problems to completely transform clinical diseases into animal models,but the ideal animal model is the premise of the mechanism research of cervical spondylosis,and it is very important to select the appropriate animal model of cervical spondylosis.OBJECTIVE:To analyze the species,sex,age,type of cervical spondylosis model and its internal molecular mechanism of animal models of cervical spondylosis in detail so as to explore how to select suitable animal models for experimental research of cervical spondylosis.METHODS:PubMed,Medline,Embase,Web of Science,WanFang,VIP,and CNKI databases were searched with Chinese and English search terms"cervical spondylosis,cervical spondylotic myelopathy,cervical spondylotic radiculopathy,cervical spondylosis of vertebral artery type,neck type cervical spondylosis,unbalanced dynamic and static forces,joint injury,neck pain,animal model."According to the inclusion and exclusion criteria,the literature was screened,and finally 61 articles were included for review and analysis.RESULTS AND CONCLUSION:Rats are the most commonly used animals,and males seem to be more popular.It is recommended to use young adult animals.According to the characteristics of molding,cervical spondylosis models were divided into cervical spondylotic myelopath,cervical spondylotic radiculopathy,neck type cervical spondylosis,and other type cervical spondylosis.The advantages and disadvantages of various modeling methods were evaluated.Based on the studies of existing animal models,the molecular mechanism of cervical spondylosis was summarized.Therapeutic signals mediate nuclear factor-κB,phosphatidylinositol-3 kinase/protein kinase B,mitogen-activated protein kinase,and other pathways to regulate the biological processes of inflammation,apoptosis and autophagy of spinal cord,nerve root,intervertebral disc,muscle and other tissues,and ultimately delay the progression of cervical spondylosis.The quality of some studies is poor,and the clinical compatibility is not high.In the future,it is necessary to further standardize the animal model of cervical spondylosis,formulate relevant guidelines,improve the credibility of the research results,and lay a solid foundation for further human clinical trials.

Aim To investigate the effects of sodium lactate(NALA)on right heart failure induced by monocrotaline(MCT)-induced pulmonary arterial hy-pertension in rats and to reveal the underlying mecha-nisms.Methods Forty male Sprague-Dawley(SD)rats were randomly allocated into four groups,with ten rats in each group,namely,MCT group,NALA group,and NALA+MCT group;the MCT and NALA+MCT groups were administered a single intraperito-neal injection of MCT at 60 mg·kg-1 to induce pul-monary hypertension,and one week later,the NALA and NALA+MCT groups received intraperitoneal in-jections of NALA at 0.1 g·kg-1(once a day,for 5 weeks),while the CON and MCT groups received e-qual volumes of physiological saline(once a day,for 5 weeks);right heart function was assessed using echo-cardiography,right ventricular and pulmonary artery remodeling were evaluated via histopathological sec-tions,and the expression levels of ANP,BNP,and in-flammatory factors were measured by ELISA,along with assessments of oxidative stress levels,Western blot detection of the expression levels of proteins in the TLR4/NF-κB signaling pathway.Results Compared to the CON group,the MCT group exhibited increased RVSP and RVHI,decreased right heart function,in-creased collagen fiber deposition,and elevated oxida-tive stress and inflammatory factor expression,and the expression levels of proteins in the TLR4/NF-κB signa-ling pathway increased(P＜0.05);compared to the MCT group,the NALA+MCT group showed reduced RVSP and RVHI,improved right heart function,atten-uated pulmonary vascular remodeling,decreased ex-pression of ANP,BNP,inflammatory factors,and H2O2,along with increased antioxidant enzyme expres-sion,and the expression levels of proteins in the TLR4/NF-κB signaling pathway decreased(P＜0.05).Conclusion NALA can inhibit right ventric-ular remodeling in rats with pulmonary hypertension,and the underlying mechanism may involve the allevia-tion of inflammatory responses and oxidative stress through the inhibition of the TLR4/NF-κB signaling pathway.

Objective To investigate the differences in demographic characteristics,reproductive health status,and the distribution of pregnancy-related diseases between couples conceived via assisted reproductive technology(ART)and naturally conceived couples,and to analyze the impact of ART treatment on the incidence of preterm birth(PTB)in singleton and twin and multiple pregnancies.Methods We conducted a retrospective analysis of the maternal and infant cohort data of Jing'an District from 2013 to 2020.Based on the conception method,the subjects were categorized into two groups:the ART group and the natural conception group.Chi-square test was applied to compare baseline characteristics and disease distributions differences between the two groups,and logistic regression models were used to evaluate the association between ART and the PTB risks.A causal mediation model was used to evaluate the mediating effect of twin and multiple pregnancy in the relationship between ART and PTB.Results A total of 117 717 parturients were included,6 265 in the ART group and 111 452 in the natural conception group.Compared with the natural conception group,couples in the ART group were significantly older and had a higher prevalence of reproductive system diseases.The incidences of diabetes and hypertensive disorders during pregnancy in ART parturient were 13.76%and 9.99%,respectively,which were significantly higher than 7.88%and 4.75%in the natural conception group(both P<0.001).The overall PTB rate in the ART group was 14.81%,higher than 5.35%in the natural conceptions group(P<0.001).The PTB rate in ART for singleton pregnancies in the ART group was 6.40%,higher than 4.83%in the natural conception group(P<0.001),while the PTB rate in ART for twin and multiple pregnancies in the ART group was 53.97%,lower than 60.42%in the natural conception group(P<0.05).Mediation analysis showed that 97.99%of the effect of ART on PTB was mediated by twin and multiple pregnancy,with ART increasing the PTB risk by 3.44 times through multiple pregnancy.Conclusion The overall PTB rate of ART recipients is higher than that of natural recipients,but ART does not increase the PTB risk in singleton and twin and multiple pregnancies.Twin and multiple pregnancy is the key mediating factor contributing to PTB in ART-conceived recipients.Compared with naturally conceived couples,ART conception couples own more advanced maternal age,and have higher risks of suffering gestational diabetes,gestational hypertension,and PTB.