ObjectiveTo clarify the relationship between intestinal flora and intestinal motility in rats with slow transit constipation （STC） and qi stagnation syndrome by conducting a pseudo-sterile experiment and fecal microbiota transplantation （FMT） technology. MethodsTwenty-four Wistar rats were randomly divided into normal group （n=6）， STC with qi stagnation pattern group （n=6） and pseudo-sterile group （n=12）. In the STC group with qi stagnation pattern， 3 mg/kg of loperamide suspension by intragastric administration combined with tail clamping stimulation were performed to establish the rat model of STC with qi stagnation pattern. After successful modeling， fresh feces from the rats in the STC with qi stagnation pattern group and the normal group were collected to prepare 100 mg/ml of fecal bacterial suspension. In the pseudo-sterile group， the antibiotic cocktail method was used （a mixed antibiotic suspension containing bacitracin， streptomycin sulfate， and neomycin sulfate at 20 mg/ml each was administered intragastrically） to establish pseudo-sterile rats model. After successful modeling， the rats were randomly divided into normal fecal bacterial liquid group and STC with qi stagnation pattern fecal bacterial liquid group， with six rats in each group， and then were given 10 ml/kg of the prepared corresponding rat fecal bacterial suspension by gavage. Rats in STC with qi stagnation pattern group were given an equal volume of sterile water by gavage. All groups were administered once a day for 7 consecutive days. The small intestinal propulsion rate of the STC with qi stagnation pattern group， the normal fecal bacterial liquid group， and STC with qi stagnation pattern fecal bacterial liquid group were compared. ELISA method was used to detect serum 5-hydroxytryptamine （5-HT） levels. Immunohistochemistry was used to detect the positive expression levels of 5-hydroxytryptamine 3 receptor （5-HT3R） and 5-hydroxytryptamine 4 receptor （5-HT4R） in colon tissue. Western blot method was used to detect the protein expression levels of tryptophan hydroxylase 1 （TPH1）， tryptophan hydroxylase 2 （TPH2）， serotonin transporter （SERT）， and monoamine oxidase A （MAO-A） in colon tissue. ResultsCompared to those in the normal fecal bacterial liquid group， the small intestinal propulsion rate， serum 5-HT level， positive expression of 5-HT3R and 5-HT4R in colon tissue， and protein expression of TPH1， TPH2， SERT and MAO-A significantly decreased in the STC with qi stagnation pattern group and STC with qi stagnation pattern fecal bacterial liquid group （P＜0.05）. There was no statistically significant difference in the indicators between the STC with qi stagnation pattern group and STC with qi stagnation pattern fecal bacterial liquid group （P＞0.05）. ConclusionThe intestinal flora in STC rats with qi stagnation pattern can lead to a slowdown in intestinal transmission function， whose mechanism may be related to intestinal motility disorders affected by the synthesis， transport， metabolism and other pathways of 5-HT.

Objective:To construct a machine-learning model for predicting the progression of pancreatic cystic lesions (PCLs) based on clinical and CT features, and to evaluate its predictive performance in internal/external testing cohorts.Methods:Baseline clinical and radiological data of 200 PCLs in 177 patients undergoing abdominal thin slice enhanced CT examination at Peking Union Medical College Hospital from July 2014 to December 2022 were retrospectively collected. PCLs were divided into progressive and non-progressive groups according to whether the signs indicated for surgery by the guidelines of the European study group on PCLs were present during three-year follow-up. 200 PCLs were randomly divided into training (150 PCLs) and internal testing cohorts (50 PCLs) at the ratio of 1∶3. 15 PCLs in 14 patients at Jinling Affiliated Hospital of Medical School of Nanjing University from October 2011 to May 2020 were enrolled as external testing cohort. The clinical and CT radiological features were recorded. Multiple feature selection methods and machine-learning models were implemented and combined to identify the optimal machine-learning model based on the 10-fold cross-validation method. Receiver operating characteristics (ROC) curve was drawn and area under curve (AUC) was calculated. The model with the highest AUC was determined as the optimal model. The optimal model's predictive performance was evaluated on testing cohort by calculating AUC, sensitivity, specificity and accuracy. Permutation importance was used to assess the importance of optimal model features. Calibration curves of the optimal model were established to evaluate the model's clinical applicability by Hosmer-Lemeshow test.Results:In training and internal testing cohorts, the progressive and non-progressive groups were significantly different on history of pancreatitis, lesions size, main pancreatic duct diameter and dilation, thick cyst wall, presence of septation and thick septation (all P value <0.05) In internal testing cohort, the two groups were significantly different on gender, lesion calcification and pancreatic atrophy (all P value <0.05). In external testing cohort, the two groups were significantly different on lesions size and pancreatic duct dilation (both P<0.05). The support vector machine (SVM) model based on five features selected by F test (lesion size, thick cyst wall, history of pancreatitis, main pancreatic duct diameter and dilation) achieved the highest AUC of 0.899 during cross-validation. SVM model for predicting the progression of PCLs demonstrated an AUC of 0.909, sensitivity of 82.4%, specificity of 72.7%, and accuracy of 76.0% in the internal testing cohort, and 0.944, 100%, 77.8%, and 86.7% in the external testing cohort. Calibration curved showed that the predicted probability by the model was comparable to the real progression of PCLs. Hosmer-Lemeshow goodness-of-fit test affirmed the model's consistency with actual PCLs progression in testing cohorts. Conclusions:The SVM model based on clinical and CT features can help doctors predict the PCLs progression within three-year follow-up, thus achieving efficient patient management and rational allocation of medical resource.

Objective:To investigate the current situation and influence factors of prehospital thrombolysis treatment for ST segment elevation myocardial infarction (STEMI) in China, to analyze the main factors affecting prehospital thrombolysis implementation, and optimize the pre-hospital thrombolysis strategy for STEMI to reduce mortality.Methods:A multicenter cross-sectional survey was conducted. 21 cities from six major geographical regions in China were selected by using convenient sampling method. An anonymous online electronic questionnaire was used to investigate the current situation and influence factors of prehospital emergency physicians and grassroots physicians implementing prehospital thrombolysis treatment for STEMI patients. Chi-square test was used to analyze the differences in count data between groups, and multivariate logistic regression was used to analyze the factors affecting prehospital thrombolysis in STEMI.Results:A total of 5 163 prehospital emergency physicians and physicians from grassroots township health centers/community health service centers or village clinics participated in this survey. Among them, 3208 (62.13%) have never implemtent thrombolysis, and 1 955 (37.87%) have did it before. The results of the multivariate logistic regression analysis indicated that physicians with 5-10 years of experience ( OR=1.41, 95% CI: 1.18-1.69, P<0.01), 11-20 years of experience ( OR=1.25, 95% CI: 1.03-1.52, P=0.02), those working in village clinics ( OR=1.30, 95% CI: 1.05-1.61, P=0.02), those in pre-hospital emergency medical institutions/departments ( OR=3.19, 95% CI: 2.80-3.64, P<0.01), those whose units are equipped with remote ECG transmission capabilities ( OR=1.72, 95% CI: 1.50-1.96, P<0.01), or ECG AI-assisted diagnostic tools ( OR=1.31, 95% CI: 1.15-1.49, P<0.01), and those who believe that thrombolysis is highly effective and should be widely adopted ( OR=2.55, 95% CI: 2.09-3.12, P<0.01) or consider it somewhat effective but warranting caution ( OR=2.11, 95% CI: 1.73-2.59, P<0.001), were more likely to make pre-hospital thrombolysis decisions for STEMI patients. To improve the current situation of pre-hospital thrombolysis for STEMI, the top four measures prioritized by pre-hospital emergency and grassroots physicians were enhancing the rescue capabilities of primary care doctors (92.22%), strengthening guidance from higherlevel hospitals (84.99%), increasing support for information technology (83.37%), and improving public health education (74.75%). Conclusions:The implementation rate of prehospital thrombolysis for STEMI in China still needs to be improved. Optimizing the prehospital thrombolysis strategy for STEMI, strengthening the allocation of basic medical resources and information technology support, and improving the referral mechanism are conducive to the implementation of prehospital thrombolysis for STEMI.

OBJECTIVE To investigate the damage effect and potential toxic mechanism of SARS-CoV-2 spike protein(S protein)on human neuroblastomacells(SH-SY5Y).METHODS SH-SY5Y were treated with S protein at concentrations of 25,50,75,and 100 mg·L-1 for 24 h.Cell viability of SH-SY5Y was detected using the CCK-8 assay.The cytotoxic lactate dehydrogenase(LDH)detection kit was used to measure the release rate of LDH,and the 5-ethynyl-2′-deoxyuridine(EdU)-488 cell prolifera-tion kit was used to assess cell proliferation.The ATP detection kit was used to measure intracellular ATP content.The JC-1 fluorescent probe method was employed to detect the mitochondrial membrane potential(MMP)of cells.Seahorse XF was used to measure mitochondrial respiratory and glycolytic capacity.RESULTS Compared with the cell control group,cell viability was significantly reduced in S protein 25,50,75 and 100 mg·L-1 groups(P<0.01),and the half-inhibition concentration(IC50)was 65.05 mg·L-1.The LDH release rate wassignificantly increased(P<0.01)and the proportion of EdU positive cellswas significantly reduced(P<0.01)in S protein 25,50,75 and 100 mg·L-1 groups.S protein signifi-cantly reduced intracellular ATP content(P<0.01)at the concentrations of 75 and 100 mg·L-1,while significantly reduced intracellular MMP(P<0.05,P<0.01)at the concentrations of 50 and 75 mg·L-1.S protein 50 mg·L-1 increased the maximum value of basal glycolysis levels and glycolytic capacity(P<0.05,P<0.01),and S protein 25 and 50 mg·L-1 increased the maximum value of respiration capacity(P<0.05,P<0.01).SH-SY5Y cell viability was positively correlated with the intracellular ATP content and the MMP level(r2=0.9209,P=0.001;r2=0.6170,P=0.0025),and negatively correlated with the maximum level of basal glycolysis and glycolytic capacity(r2=0.5194,P=0.0285;r2=0.6664,P=0.0073),and nega-tively correlated with ATP production capacity(r2=0.8204,P=0.0008).CONCLUSIONS protein decreases the viability of SH-SY5Y cells and inhibited cell proliferation.The mechanism may be closely related to the disorder of energy metabolism.

OBJECTIVE To investigate the damage effect and mechanisms of cyclophosphamide(CTX)and its active metabolite derivative 4-hydroperoxycyclophosphamide(4-HC)to human neuroblas-toma SH-SY5Y cells.METHODS SH-SY5Y cells were treated with CTX[0(cell control),0.01,0.1,1,5,10,20,40 and 80 mmol·L-1]and 4-HC[0(cell control),0.01,0.1,1,5,10,20,40 and 80 μmol·L-1]for 48 h.Cell confluence and morphology were observed by the IncuCyte ZOOM system.Cell viability was assessed by CCK-8 assay.Lactate dehydrogenase(LDH)release was measured by LDH assay kit.SH-SY5Y cells were treated with CTX(0,1,5,10 and 20 mmol·L-1)and 4-HC(0,1,5,10 and 20 μmol·L-1)for 48 h before cell proliferation was analyzed by 5-ethynyl-2′-deoxyuridine(EdU)staining assay.Immunofluorescence was employed to assess the levels of the DNA double-strand break marker γ-H2AX and to evaluate changes in mitochondrial membrane potential.SH-SY5Y cells were treated with CTX(0,1,5 and 10 mmol·L-1)and 4-HC(0,1,5 and 10 μmol·L-1)for 48 h,and the alterations in glycolysis and oxidative phosphorylation levels were analyzed using the Seahorse XFe96 Analyzer.RESULTS Compared with the cell control group,cell confluence and cell viability were significantly reduced in the CTX and 4-HC groups(P<0.01),and the half-maximal inhibitory concentrations(IC50)for CTX and 4-HC were 4.44 mmol·L-1 and 4.78 μmol·L-1,respectively.The release rate of LDH was signif-icantly increased while the percentage of EdU+cells was significantly reduced in the CTX and 4-HC groups(P<0.01).The percentage of γ-H2AX+cells was significantly increased and mitochondrial membrane potential significantly decreased in the CTX and 4-HC group(P<0.05).Treatment with CTX and 4-HC resulted in reduced levels of maximum glycolytic capacity,glycolytic reserve,maximal respi-ration,and ATP production(P<0.05).CONCLUSION CTX and 4-HC exert significant cytotoxic effects on SH-SY5Y cells by disrupting cell membrane structure,impeding cell proliferation,and reducing cell viability.The mechanisms underlying these effects may involve intracellular DNA damage,disturbance of energy metabolism and mitochondrial dysfunction.

Objective:To investigate the characteristics of anorectal dynamics in elderly patients with functional defecation disorders(FDD), and to provide a basis for their diagnosis, treatment and prevention.Methods:In this retrospective study, 226 patients with FDD receiving 3D high-resolution anorectal manometry were divided into an elderly group(93 cases)and a non-elderly group(133 cases). Results from anorectal manometry parameters were compared and analysis of patterns of anorectal pressure changes in elderly participants based on sex, the Bristol stool classification and clinical symptoms was conducted.Results:The resting anal pressure, rectal pressure and anal relaxation rate were lower( t=-3.407, -2.051, Z=2.548, P=0.001, 0.040, 0.011)and the volume of first sensation was higher( t=1.998, P=0.047)in the elderly group than in the non-elderly group.The maximum anal squeezing pressure, residual anal pressure and maximum tolerated volume were higher( t=4.589, 4.730, 2.025, all P<0.05), whereas the anal relaxation rate and anorectal pressure gradient were lower in elderly men than in elderly women( Z=4.059, t=-3.714, P<0.001 for both). Regarding the types of FDD, both the elderly group and the non-elderly group were dominated with type Ⅱ defecation disorder, with more men than women having type Ⅱ defecation disorder in the elderly group( χ2=10.343, P=0.001). In cases of paradoxical sphincter contraction during simulated defecation, the incidence in the elderly group was 80.65%(75/93), which was higher than 68.42%(91/133)in the non-elderly group( χ2=4.194, P=0.041). The volume of first sensation, volume of first defecation sensation, and maximum tolerated volume of patients in the elderly group without the urge to defecate were(59.86±23.84)ml, (96.76±34.61)ml, and(144.32±30.57)ml, respectively, higher than those of patients with the urge to defecate(46.79±17.20)ml, (75.26±28.75)ml, and(120.00±40.28)ml( t=-2.241, -2.493, -2.891, P=0.027, 0.014, 0.005). The rectal pressure(26.52±16.08)mmHg of patients with defecation dyssynergia was lower than that of patients without defecation dyssynergia(39.91±8.82)mmHg(1 mmHg=0.133 kPa)( t=-3.128, P=0.002), while the resting anal pressure of patients with defecation dyssynergia(90.60±28.44)mmHg was higher than that of patients without defecation dyssynergia(73.65±27.10)mmHg( t=-2.201, P=0.030). The resting anal pressure and maximum anal squeezing pressure in patients with anal blockage sensation[(87.11±24.64)mmHg, (149.28±48.29)mmHg]were higher than those in patients without anal blockage sensation[(72.43±20.02)mmHg, (121.76±26.35)mmHg]( t=2.954、3.066, P=0.004、0.003). There was no significant difference in values from parameters of anorectal dynamics between patients with different Bristol stool types, with and without incomplete defecation or with different degrees of abdominal distension(all P>0.05). Conclusions:Anorectal dynamics in patients with FDD are characterized by paradoxical anal sphincter movements, but older patients with FDD are mainly characterized by inadequate rectal propulsion, pelvic floor muscle dysfunction and reduced rectal sensitivity.

Objective To observe the efficacy of continuous renal replacement therapy (CRRT) combined with hemoperfusion (HP) on patients with severe acute aconitine poisoning. Methods One patient suffered from severe acute aconitine poisoning was admitted into the Department of Critical Care Medicine of Affiliated Hospital of Guizhou Medical University, besides the gastric lavage and multi-organ supportive conventional therapies, CRRT combined with HP was given to the patient and his clinical data of life vital signs and other parameters were observed. Results After the patient underwent 4 episodes of CRRT (102 hours in total) and HP (8 hours in total) based on the conventional treatment, 4 days later, the disease situations were gradually stabilized, all of their parameters became gradually normal, the patient successfully weaned off from mechanical ventilation, the via mouth tracheal intubation was pulled out and the patient was transferred out of department of critical care medicine. Conclusion In the patient with acute aconitine poisoning, it is necessary to use CRRT combined with HP as early as possible, that can effectively eliminate the toxicant in the body and quickly correct the electrolytic and acid-base disturbances, so as the above combine method can improve the patient's prognosis and elevate the successful rescue rate.

Objective To study the expression level and function of micro RNA (microRNA)-218 in hepatocellular carcinoma (HCC) .Methods 46 cases of HCC surgery in the hepatobiliary surgery department of this hospital were selected and divided into the transfection group and nontransfection group .The expression ,proliferation and apoptosis of microRNA-218 and the expression level of B cell specific Maloney leukemia virus insertion site 1(Bmi-1) and cycling-dependented kinase 6(CDK6) in HepG2 cells were compared between the two groups .Results The expression level of microRNA-218 in HCC tissue was significantly lower than that in paracancerous tissues (P＜0 .05);the microRNA218 expression level was closely correlated with the clinicopathological characteristics such as tumor size and TNM stage(P＜0 .05);the HepG2 cell proliferation rates at 24 ,48 ,72 h after transfection in the transfection group were significantly lower than those in the nontransfection group(P＜0 .05);the HepG2 cell apoptosis rate in the transfection group was significantly higher than that in the nontransfection group(P＜0 .05);the Bim-1 and CDK6 expression levels after HepG2 cell transfection in the transfection group were significantly lower than those in nontransfection group(P＜0 .05) . Conclusion microRNA-218 can suppress the proliferation of HCC cells and promotes HCC cells apoptosis by down-regulating the Bim-1 and CDK6 expression level in potential targets .

Objective To explore the neural damage induced by acute exposure to methamphetamine (METH).Methods The mice were administrated with METH,then the stereotyped behavior of mice was evaluated,and spatial recognition memory was analyzed by Y-maze test.In addition,nitric oxide synthase (NOS) activity was detected by kit,and the apoptotic proteins including Bax,Bcl-2,Caspase-3 were assayed by using Western blot.The DNA injury induced by METH was observed by using the comet assay.Moreover,mitochondrial membrane potential was detected to assess the toxic effects of METH on mitochondria by JC-1.With the Western blot assay,the phosphorylation of MAPK signaling pathways were also investigated.Results Acute METH exposure significantly increased the stereotyped behavior in mice,and spatial recognition ability of mice was obviously decreased.On the molecular level,total nitric oxide synthase (TNOS) and induced nitric oxide synthase (iNOS) were increased,and the apoptotic proteins,such as Bax and cleaved caspase-3 were markedly enhanced.With the comet assay,it showed that METH exposure resulted in DNA damage.In parallel,mitochondrial membrane was damaged which manifested as mitochondrial membrane potential decreased.With the western blot,It was further found that METH enhanced the activation of MAPKs.However,p38 MAPK signahng pathway was demonstrated to be the only one factor involved in METH-induced neural damage.Conclusion METH induced neural damage,and MAPK signaling pathways might be involved in this process,since inhibition of p38 MAPK signaling pathway significantly ameliorated METH-induced neural damage.