BACKGROUND:The absence of blood vessels in tendon tissue makes tendon repair challenging.Therefore,improving tendon healing and raising the efficacy of stem cell and other therapeutic cell transplantation after tendon damage have become hotspots for research in both clinical and scientific contexts. OBJECTIVE:The stem cells and gelatin microcarrier scaffold were joined to form tissue engineered stem cells.Human umbilical cord mesenchymal stem cells cultured in gelatin microcarriers were used to investigate the therapeutic impact and mode of action on tendinopathy healing in rats in vitro and In vivo. METHODS:(1)In vitro cell experiments:After seeding human umbilical cord mesenchymal stem cells with three-dimensional gelatin microcarriers,the cell vitality and survival were assessed.Human umbilical cord mesenchymal stem cells conventionally cultured were cultured as controls.(2)In vivo experiment:Adult SD rats were randomly assigned to normal group,tendinopathy group,2D group(tendinopathy+conventional culture of human umbilical cord mesenchymal stem cells),and 3D group(tendinopathy+gelatin microcarrier three-dimensional culture of human umbilical cord mesenchymal stem cells),with 6 rats in each group.Four weeks after therapy,animal behavior tests and histopathologic morphology of the Achilles tendon was examined. RESULTS AND CONCLUSION:(1)In vitro cell experiments:the seeded human umbilical cord mesenchymal stem cells on gelatin microcarriers showed high viability and as time went on,the stem cell proliferation level grew.Compared with the control group,3D stem cell culture preserved cell viability.(2)In vivo experiment:Following a 4-week treatment,the 3D stem cell culture group showed a significant improvement in both functional recovery of the lower limbs and histopathological scores when compared to the tendinopathy group.The 2D stem cell culture group also showed improvement in tendinopathy injury,but its effect is not as much as the 3D stem cell culture group.(3)The outcomes demonstrate that human umbilical cord mesenchymal stem cells cultured with three-dimensional gelatin microcarrier can promote the repair and regeneration of tendon injury tissue,and the repair effect is better than that of conventional human umbilical cord mesenchymal stem cells.

ObjectiveTo explore the possible mechanism of Yigan Fupi Prescription （抑肝扶脾方， YFP） in treating diarrhea-type irritable bowel syndrome （IBS-D） by investigating the AKT/mTOR signaling pathway. MethodsSixty SD rats were randomly divided into control group， model group， YFP low-， medium-， and high-dose group， and pinaverium bromide group， with 10 rats in each group. All groups but the control group， were subjected to 21 days of tail-clamping stimulation and 14 days of senna leaf gavage to establish a liver stagnation and spleen deficiency-type IBS-D rat model. After successful modeling， the YFP low-， medium-， and high-dose group were administered 0.96， 1.93， and 3.87 g/（kg·d） of the prescription， respectively. The pinaverium bromide group was given 13.5 mg/（kg·d）， while the control and model groups were given 10 ml/（kg·d） distilled water. All groups were administered once daily for 14 consecutive days. General conditions of the rats were recorded during the experiment， and after modeling and drug administration， body weight， Bristol stool score， abdominal withdrawal reflex （AWR） score， and histo pathology of colon tissue were observed under HE staining. ELISA was used to detect serum levels of tumor necrosis factor α （TNF-α）， interleukin-1β （IL-1β）， and interleukin-6 （IL-6）. Immunofluorescence was employed to detect the levels of AKT/mTOR pathway-related proteins including phosphorylated AKT （p-AKT）/AKT and phosphorylated mTOR （p-mTOR）/mTOR in the colon tissue. Western Blotting was used to detect the levels of autophagy-related proteins， including UNC-51-like kinase 1 （ULK1）， Beclin1 and LC3， and tight junction proteins including Occludin and ZO-1 in the colon tissue. ResultsAfter modeling， compared to the control group， the body weight of rats in the other groups decreased， and Bristol stool scores， as well as AWR scores under 20， 40， 60， and 80 mmHg increased （P＜0.05 or P＜0.01）. After drug administration， compared to the control group， the model group showed reduced body weight， decreased ULK1， Beclin1， LC3Ⅱ/LC3Ⅰ， Occludin， and ZO-1 protein levels in the colon tissue （P＜0.05 or P＜0.01）， and increased Bristol stool scores， AWR scores， serum TNF-α， IL-1β， and IL-6 levels， as well as p-AKT/AKT and p-mTOR/mTOR protein relative expression levels （P＜0.05 or P＜0.01）. Pathological results showed a significant reduction in goblet cells in the upper part of the glandular layer of the colon， with mild inflammatory cell infiltration. The submucosal collagen fibers were dissolved， with unclear boundaries， pale staining， and microvascular congestion and dilation. Compared with the model group， the YFP low-， medium-， and high-dose group and the pinaverium bromide group showed increased body weight， Beclin1， Occludin， and LC3Ⅱ/LC3Ⅰ protein levels （P＜0.05 or P＜0.01）， and decreased Bristol stool scores， AWR scores under 40， 60， and 80 mmHg， serum IL-1β， IL-6， TNF-α levels， and p-AKT/AKT， p-mTOR/mTOR protein relative expression levels （P＜0.05 or P＜0.01）. The pathological morphology of the rats in the YFP groups and pinaverium bromide group showed varying degrees of improvement. Compared with the pinaverium bromide group， the YFP low- and medium-dose group showed increased AWR scores under 20， 40， and 60 mmHg （P＜0.05）. The YFP low-dose group had reduced TNF-α， IL-1β， and IL-6 levels， and increased p-mTOR/mTOR protein relative expression levels occured in all YFP groups （P＜0.05）. Compared with the YFP low-dose group， the YFP high-dose group and pinaverium bromide group showed decreased AWR scores under different pressure levels and reduced p-AKT/AKT protein relative expression levels， while the YFP medium- and high-dose group had elevated serum TNF-α， IL-1β levels and reduced p-mTOR/mTOR protein relative expression levels （P＜0.05）. ConclusionYFP can effectively improve the pathological injury of colon tissue in IBS-D model rats with liver stagnation and spleen deficiency， reduce Bristol stool and AWR scores， and its mechanism may be related to reducing level of inflammatory factors and inhibiting AKT/mTOR pathway-related proteins in colon tissue， thereby enhancing the expression of autophagy-related proteins in the colon tissue.

ObjectiveThe study explores the influence of voluntary wheel running on the behavioral abnormalities and the activation state of the hypothalamic-pituitary-adrenal (HPA) axis in autism spectrum disorder (ASD) rats through gut microbiota. MethodsSD female rats were selected and administered either400 mg/kg of valproic acid (VPA) solution or an equivalent volume of saline via intraperitoneal injection on day 12.5 of pregnancy. The resulting offspring were divided into 2 groups: the ASD model group (PASD, n=35) and the normal control group (PCON, n=16). Behavioral assessments, including the three-chamber social test, open field test, and Morris water maze, were conducted on postnatal day 23. After behavioral testing, 8 rats from each group (PCON, PASD) were randomly selected for serum analysis using enzyme-linked immunosorbent assay (ELISA) to measure corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) concentration, to evaluate the functional state of the HPA axis in rats. On postnatal day 28, the remaining 8 rats in the PCON group were designated as the control group (CON, n=8), and the remaining 27 rats in the PASD group were randomly divided into 4 groups: ASD non-intervention group (ASD, n=6), ASD exercise group (ASDE, n=8), ASD fecal microbiota transplantation group (FMT, n=8), and ASD sham fecal microbiota transplantation group (sFMT, n=5). The rats in the ASD group and the CON group were kept under standard conditions, while the rats in the ASDE group performed 6 weeks of voluntary wheel running intervention starting on postnatal day 28. The rats in the FMT group were gavaged daily from postnatal day 42 with 1 ml/100 g fresh fecal suspension from ASDE rats which had undergone exercise for 2 weeks, 5 d per week, continuing for 4 weeks. The sFMT group received an equivalent volume of saline. After the interventions were completed, behavioral assessments and HPA axis markers were measured for all groups. ResultsBefore the intervention, the ASD model group exhibited significantly reduced social ability, social novelty preference, spontaneous activity, and exploratory interest, as well as impaired spatial learning, memory, and navigation abilities compared to the normal control group (P<0.05). Serum concentration of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT) in the PASD group were significantly higher than those in the PCON group (P<0.05). Following 6 weeks of voluntary wheel running, the ASDE group showed significant improvements in social ability, social novelty preference, spontaneous activity, exploratory interest, spatial learning, memory, and navigation skills compared to the ASD group (P<0.05), with a significant decrease in serum CORT concentration (P<0.05), and a downward trend in CRH and ACTH concentration. After 4 weeks of fecal microbiota transplantation in the exercise group, the FMT group showed marked improvements in social ability, social novelty preference, spontaneous activity, exploratory interest, as well as spatial learning, memory, and navigation abilities compared to both the ASD and sFMT groups (P<0.05). In addition, serum ACTH and CORT concentration were significantly reduced (P<0.05), and CRH concentration also showed a decreasing trend. ConclusionExercise may improve ASD-related behaviors by suppressing the activation of the HPA axis, with the gut microbiota likely playing a crucial role in this process.

Objective To investigate the expression and significance of microRNA(miR)-4429 and microRNA(miR)-19-3p level in patients with pelvic floor dysfunctional(PFD)disease.Methods A total of 90 PFD patients admitted to the Second People's Hospital of Hengshui from June 2021 to June 2022 were selected as the PFD group.They were grouped into the pelvic organ prolapse(POP)group(n=50),the stress urinary incontinence(SUI)group(n=25),and the POP combined with SUI group(n=15).Meanwhile,80 healthy women who were examined in the Second People's Hospital of Hengshui were collected as the control group.The general data such as delivery mode,previous abortion history and family history were compared between the control group and the PFD group.The levels of serum miR-4429 and miR-19-3p in each group were compared.The diagnostic value of serum miR-4429 and miR-19-3p levels in PFD was analyzed by receiver operating characteristic(ROC)analysis.Logistic regression analysis was applied to analyze the factors affecting PFD.The paired sample t-test was applied to compare the changes in serum miR-4429 and miR-19-3p levels before and after PFD treatment.Results There were significant differences between the PFD group and the control group in terms of delivery mode,previous abortion history,and PFD family history,and the differences were statistically significant(t=4.415,6.444,4.707,all P＜0.05).The serum miR-4429(0.71±0.19 vs 1.00±0.25)level in the PFD group was lower than that in the control group,while the miR-19-3p(1.44±0.35 vs 1.01±0.28)level was higher than that in the control group,and the differences was statistically significant(t=8.927,8.772,all P＜0.05).The serum miR-4429(0.73±0.22,0.74±0.16 vs 0.59±0.16)level in the POP and SUI groups was higher than that in the POP combined SUI group,while the serum miR-19-3p(1.35±0.39,1.41±0.31 vs 1.77±0.56)level in the POP group and SUI group was lower than that in the POP combined with SUI group,with significant differences(t=3.531,3.411;5.003,3.865,all P＜0.05).ROC analysis showed that the areas under curve(AUC)for miR-4429 and miR-19-3p to assist in assessing whether PFD occurs were 0.805 and 0.825,respectively.The AUC of the combined detection was 0.865.Multivariate logistic regression analysis showed that miR-19-3p was a risk factor affecting PFD,while miR-4429 was a protective factor.After treatment,serum miR-4429(0.93±0.23 vs 0.71±0.19)level in PFD patients increased,while the miR-19-3p(1.12±0.29 vs 1.44±0.35)level decreased,the diffences were statistically significant(t=6.996,6.679,all P＜0.05).Conclusion The serum miR-4429 level in patients with PFD decreased,while the miR-19-3p level increased.The levels of miR-4429 and miR-19-3p in serum were closely related to the occurrence and development of PFD diseases,which can be used as evaluation indicators to predict PFD.

Objective To study the mechanism of polyene phosphatidylcholine in improving metabolic disorders and fatty liver induced by high fat diet.Methods Thirty-two C57BL/6 mice were randomly divided into blank group,control group,model group and experimental group.The blank group was fed with low-fat diet and intraperitoneal injection of 10％glucose 200 μL twice a week.Control group was fed with low-fat diet twice a week and intraperitoneally injected 10％glucose solution 200 μL containing polyene phosphatidylcholine(PPC)20 μg.Model group was fed with high-fat diet and intraperitoneal injection of 10％glucose 200 μL twice a week.Experimental group was fed with high-fat diet twice a week and intraperitoneally injected 10％glucose solution 200 μL containing PPC 20 μg.The body weight of the mice was measured,blood glucose test strips and insulin resistance was analyzed.The levels of triglyceride(TG),high density lipoprotein(HDL),low density lipoprotein(LDL),glutamic oxalic aminotransferase(GOT)and glutamic pyruvic aminotransferase(GPT)in serum and liver were analyzed by biochemical method.The levels of tumor necrosis factor-α(TNF-α),interleukin-6 and IL-8 were detected by enzyme-linked immunosorbent assay(ELISA).Results The serum TG levels of blank group,control group,model group and experimental group were(0.15±0.01),(0.11±0.01),(0.21±0.01)and(0.12±0.01)mmol·L-1;LDL levels were(0.41±0.01),(0.25±0.01),(0.71±0.02)and(0.49±0.01)mmol·L-1;GOT levels were(30.30±0.89),(31.39±1.18),(43.04±2.82)and(25.64±0.72)mmol·L-1;GPT levels were(9.15±0.45),(7.39±1.88),(12.87±1.81)and(7.96±1.64)mmol·L-1;fasting blood glucose levels were(4.97±0.08),(6.08±0.18),(8.12±0.20)and(7.29±0.02)mmol·L-1;fasting insulin levels were(6.52±1.11),(5.45±0.28),(54.83±4.32)and(30.55±2.73)mU·L-1;the levels of TNF-α in liver tissues were(3.98±0.63),(3.95±0.98),(20.55±4.71)and(15.28±1.73)pg·g-1;IL-6 levels were(18.93±8.56),(17.64±3.29),(59.40±4.63)and(37.54±7.33)pg·g-1;IL-8 levels were(67.16±12.37),(59.44±3.58),(198.40±9.27)and(132.10±7.04)pg·g-1.The difference of above indicatory between experimental group and model group was statistically significant(all P＜0.05).Conclusion Polyene phosphatidylcholine may inhibit the expression of TNF-α,IL-6 and IL-8 inflammatory factors by mediating the inhibition of inflammation on liver tissue and then improve metabolic disorders.

Objective To study the activity of ten kinds of antipyretic-antidotal traditional Chinese medicine(TCM),including radix tinosporae.herb of blin conyza and turmeric,against extensively drug-resistant Acineto-bacter baumannii(XDR-AB)infection,screen out the extracts of antipyretic-antidotal TCM which have in vivo anti-infection activity,provide a research basis for the discovery of novel antimicrobials against XD-RAB infection.Methods Ten antipyretic-antidotal TCM were extracted with water,50％ethanol and 95％ethanol respectively,and TCM extracts with different concentrations were prepared,which were co-incubated with the model of XDR-AB-infected Caenorhabditis elegans previously optimized by the research group.The in vivo activity of antipyretic-antidotal TCM against XDR-AB infection was judged through the survival rate of Caenorhabditis elegans.Results With the increase of concentration of turmeric and cortex pseudolaricis extracts,the survival rate of XDR-AB-infec-ted nematodes continued to improve.The water extract,50％ethanol extract,and 95％ethanol extract of turmeric at a concentration of 1 000 μg/mL could increase the survival rates of XDR-AB-infected Caenorhabditis elegans to 54.2％(compared to the negative control group,P＜0.001),18.8％,and 13.3％,respectively.The water ex-tract,50％ethanol extract,and 95％ethanol extract of cortex pseudolaricis at a concentration of 1 000 μg/mL could increase the survival rates of XDR-AB-infected Caenorhabditis elegans to 47.4％(compared to the negative control group,P＜0.001),23.8％,and 15.8％,respectively.Conclusion The water extracts of turmeric and cortex pseudolaricis have good activity against XDR-AB infection,and their main chemical components can be tested for in vitro antimicrobial efficacy to discover novel antimicrobial agents against XDR-AB infection.

Objective:To explore the early coagulation function changes of penetrating intestinal firearm injury of pig in high-altitude environments.Methods:Twenty healthy long white piglets were selected and divided into the plain group and the high-altitude group using the random number table method, with 10 pigs in each group. Pigs in the plain group were placed in a plain environment at an altitude of 800 meters, while pigs in the high-altitude group were placed in an experimental chamber simulating an altitude of 6 000 meters for 48 hours. Both groups received pistol gunshot to have firearm penetrating wounds to the abdominal intestinal tract and then returned to the plain observation room. At 0, 2, 4, 8, 12 and 24 hours after injury, coagulation in the peripheral blood and fibrinolytic indexes [prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen (Fbg), D-dimer (D-D), and fibrinogen degradation product (FDP)], thromboelastogram (TEG) [reaction time (R), clotting time (K), clot formation rate (α), maximum amplitude (MA) and coagulation composite index (CI) ], platelet parameters [platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), and platelet-large cell ratio (P-LCR)] in the two groups were detected separately.Results:The PT values at 0 and 2 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 8, 12 and 24 hours than those in the plain group ( P<0.01); there was no significant difference at 4 hours between the two groups ( P>0.05). The APTT values at 0, 2 and 4 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The TT values at 0, 2 and 4 hours after the injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 12 and 24 hours after injury than those in the plain group ( P<0.01); there was no significant difference at 8 hours after injury between the two groups ( P>0.05). The Fbg, D-D and FDP values at 0, 2, 4, 8, 12 and 24 hours after injury were higher in the high-altitude group than those in the plain group ( P<0.01). The R values at 0, 2 and 4 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The K values at 0, 2, 4 and 8 hours after injury in the high-altitude group were significantly lower than those in the plain group, while they were significantly higher at 12 and 24 hours after injury than those in the plain group ( P<0.05 or 0.01). The α angles at 0, 2 and 4 hours after injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The MA values at 0, 2 and 4 hours after the injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The CI values at 0, 2 and 4 hours after injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 8, 12 and 24 hours after injury than those in the plain group ( P<0.01). The PLT values at 0, 2, 4 and 8 hours after injury in the high-altitude group were significantly higher than those in the plain group, while they were significantly lower at 12 and 24 hours after injury than those in the plain group ( P<0.05 or 0.01). The MPV values at 0, 2, 4, 8, 12 and 24 hours after injury in the high-altitude group were significantly higher than those in the plain group ( P<0.01). The PDW values at 2, 4, 8, 12 and 24 hours after injury in the high-altitude group were significantly higher than those in the plain group ( P<0.05 or 0.01), while there was no significant difference in PDW at 0 hour after injury between the two groups ( P>0.05). The P-LCR values at 0, 2, 4, 8, 12 and 24 hours after injury in the high-altitude group were all significantly higher than those in the plain group ( P<0.01). Conclusion:Compared with the plain environments, pig intestinal firearm penetrating injury in the high-altitude environments is more prone to early hypercoagulable state accompanied by mild hyperfibrinolysis, and faster to reach a hypocoagulable state accompanied by obvious hyperfibrinolysis.

Objective To explore the optimal image-guided verification mode by using combined cone-beam CT(CBCT)and ExacTrac X-ray(ETX)image-guided system for the position verification during the first and remaining fractionated radiotherapy of high-grade glioma patients.Methods Twenty high-grade glioma patients undergoing intensity-modulated radiotherapy at some hospital from January 2018 to June 2020 were analyzed retrospectively.CBCT image-guided system was used for the patients treated for the first time to determine the corresponding position of the treatment center on the body surface and to reset and mark the treatment center,then on-line auto registration of the CBCT images with CT positioning images was carried out,and the residual setup errors were verified with ETX image-guided system;position verification of the setup errors was performed with ETX image-guided sysem during the remaining fractionated treatment.The setup errors and their interval distributionswere calculated for the patients in six directions including left-right direction(Lat),head-foot direction(Lng),anterior-posterior direction(Vrt),rotation around left-right(Pitch),rotation around head-foot(Roll)and rotation around anterior-posterior(Yaw).SPSS 22.0 statistical software was used for data analysis.Results There were 75％patients treated for the first time and 78.62％ones undergoing the remaining fractionated radiotherapy only needed one time of setup error corre-ction.Combined CBCT and ETX image-guided resetting during the first radiotherapy met clinical requirements;during the remaining fractionated radiotherapy there were significant differences between the setup errors in the six directions before and after calibration(P＜0.05).The interval distribution of setup errors showed the error values in the six directions were all restricted within 0 to 1 mm and within 0° to l °during the first and remaining fractionated radiotherapy.Conclusion Involve-ment of combined CBCT and ETX image-guided system in the first and remaining fractionated radiotherapy of high-grade glioma patients after operation contributes to determining and resetting the treatment center rapidly and accurately,decreasing setup errors and enhancing the accuracy and repeatability of radiotherapy.[Chinese Medical Equipment Journal,2024,45(8):57-62].

Objective To investigate the potential risk factors for immune checkpoint-related pneumonia(CIP)in non-small cell lung cancer(NSCLC)patients treated with immune checkpoint inhibitors(ICIs),to identify high-risk patients with CIP at an early stage.Methods A total of 728 NSCLC patients treated with ICIs at the First Affiliated Hospital of Zhengzhou University from January 2020 to June 2023 were retrospectively selected,including 47 cases with CIP(CIP group),and 141 matched NSCLC patients without CIP(control group).Clinical data,laboratory tests,and CT images before the first immunotherapy were collected for all patients in two groups.The FACT medical imaging software was utilized for quantitative emphysema assessment in patients'CT scans.Univariate and multivariate logistic regression analyses were conducted to identify the risk factors associated with CIP.Receiver operating characteristic(ROC)curves were plotted to evaluate the predictive value of these factors for CIP occurrence in NSCLC patients.Results Among the 47 CIP patients,40(85.1%)were male,with 25(53.0%)aged between 41 and 65 years.Grade 3 pneumonia according to the Common Terminology Criteria for Adverse Events(CTCAE)was found in 28(59.6%)cases,characterized by a predominant reticular radiographic pattern.Multivariate logistic regression analysis showed that a low albumin level(OR=0.889,95%CI 0.808-0.979,P=0.017),targeted therapy(OR=9.204,95%CI 1.678-50.486,P=0.011),anti-angiogenic therapy(OR=0.056,95%CI 0.020-0.161,P<0.001),and a high percentage of low attenuation area(LAA%)(OR=1.227,95%CI 1.053-1.430,P=0.009)were significant factors influencing CIP occurrence.The combined predictive model using these four factors showed an area under the ROC curve of 0.888(95%CI 0.838-0.939),with a sensitivity of 0.894 and a specificity of 0.801 for predicting CIP in NSCLC patients.Conclusions Low serum albumin,first-line targeted therapy,and high LAA%are identified as risk factors for CIP occurrence,while anti-angiogenic therapy is a protective factor.The predictive model based on these four variables effectively predicts the risk of CIP in NSCLC patients.

Objective To evaluate the effect of delayed cleaning on the cleaning and disinfection quality of gastro-scopes after pre-treatment with different solutions.Methods According to the factorial design table,combination of the pre-treatment cleaning solutions(factor A)(including multi-enzyme cleaning solution[A1],clean water[A2])and delayed cleaning durations(factor B)(including 0 minutes after pre-treatment[B1],30 minutes after pre-treat-ment[B2],1 hour after pre-treatment[B3],and 3 hours after pre-treatment[B4])yielded eight groups(A1B1,A1B2,A1B3,A1B4,A2B1,A2B2,A2B3,A2B4).According to the usage order of gastroscopes,96 gastroscopes used in the digestive endoscopy center of a tertiary first-class hospital from May to September,2023 were randomly assigned to each group by random number table method,with 12 gastroscopes in each group.Specimens were taken at four time points:after pre-treatment,before cleaning,after cleaning,and after disinfection.Due to instant clea-ning,no specimen before cleaning were taken from A1B1 and A2B1 groups,thus only 3 specimens were taken from these two groups each.Four specimens were taken from gastroscopes in the rest groups,resulting in 360 specimens in total.The internal condition of the biopsy cavity was observed through a cavity detector during each delayed cleaning period after pre-treatment,and specimens were taken at the subsequent reprocessing processes of the gas-troscopes.The microbial conditions of the gastroscopes after pre-treatment,before cleaning,after cleaning,and af-ter disinfection were compared.Results After pre-treatment with multi-enzyme cleaning solution and clean water,there was no statistically significant difference in microbiological detection result(P＞0.05).The biopsy cavity re-mained moist during the delayed cleaning period.There was no statistically significant difference in the microbial de-tection results of factors A and B before and after delayed cleaning as well as after disinfection(all P＞0.05).There was no interaction effect between factor A and B.The distribution of bacterial colonies and disinfection qualified rate of gastroscopes after pre-treatment with two cleaning solutions were also not statistically different(both P＞0.05).Conclusion Delayed cleaning for 30 minutes,1 hour,and 3 hours after pre-treatment does not affect the cleaning and disinfection quality of gastroscopes.When clinical demand is urgent,immediate cleaning should be carried out.However,a certain buffering time(no longer than 3 hours)before cleaning is acceptable,when cleaning and disin-fection workload is heavy and timely cleaning cannot be carried out.