Objective To establish a double-antibody sandwich ELISA for the rapid detection of shiga toxin typeⅡ ( StxⅡ) in shiga toxin-producing Escherichia coli ( STEC) infection. Methods A pool of murine hybridomas was used to screen out the optimal antibody pair for the establishment of double-anti-body sandwich ELISA. The established ELISA system was used to detect StxⅡin the culture supernatants of 16 clinical strains of STEC. Specificity and sensitivity of the established ELISA system were also evaluated. Results Two antibodies, S2D8 and S2C6, were successfully screened out, based on which the double-anti-body sandwich ELISA was set up. StxⅡand its variants rather than StxⅠwas detected in the culture super-natants of STEC with a lowest detection limit of 4 ng/ml. Its performance was consistent with that of commer-cial colloidal gold test kit, indicating the characteristics of good specificity and sensitivity. Conclusion The S2D8/S2C6-based ELISA laid a foundation for researches which designates the shiga toxin as a potential can-didate on the diagnosis and therapy of STEC infection.

Objective To investigate the influence of tissue-specific growth hormone receptor (GHR)deficiency in type 1 diabetes in the mice at the gene level using pancreaticβcells combined with streptozotocin (STZ)-induced type 1 diabetes model.Methods The experiment was divided into four groups:knockout mice group (LLc knockout group), using the homozygotes (LLc:LL+Cre) producted by pancreaticβ cell-specific expressed recombinant enzyme mice (RIP-Cre)and Cre-LoxP system modified GHR mice (Floxed,LL);LL control group, containing Floxed GHR allele homozygous mice (LL);LLc STZ group and LL STZ group (STZ was used for inducing type 1 diabetes model mice). The mice with feeding glucose≥25 mmol · L-1 were considered to be successful models.The Glucose Tolerance Test (GTT),pancreas tissue HE staining and immunohistochemistry were performed in the mice.Results The blood glucose of the mice in LL STZ group and LLc STZ group and LLc STZ group were increased after inj ection of STZ and the models achieved the diagnostic criteria for diabetes 1 6 d later.The results of GTT showed that compared with LLc control group and LLc knockout group, the blood glucose levels of the mice in LL STZ and LLc STZ groups were increased (P<0.05).There was no significant change of morphology and structure of islets between LL control group and LLc knockout group detected by HE staining. The immunohistochemistry results showed that the insulin level of the mice in LL STZ group was significantly reduced compared with LL control group;the insulin level of the mice in LLc STZ group was reduced compared with LLc control group.Conclusion Pancreaticβcell GHR gene knockout has no effect on the blood glucose and the function ofβcells in the mice with STZ-induced type 1 diabetes.

Objective To evaluate conventional ultrasound combined with real-time elastography in differential diagnosis of metastatic axillary lymph nodes of breast cancer with a logistic regression model.Methods Conventional ultrasound and real-time elastography were performed in 112 breast cancer patients with 113 axillary lymph nodes.All the cases were confirmed with pathological examinations after surgery. A binary logistic regression model based on ultrasonographic features was developed.A receiver operator characteristic ( ROC) curve was constructed to assess the performance of the model.Results There were 28 nodes with no metastasis and 85 with metastasis in a total of 113 axillary lymph nodes.Three ultrasonographic features including the elastic strain ratio(SR), elastic score and shape were finally selected into the logistic regression model .The correct rate of the logistic regression model for predicting axillary lymph node metastasis was 93.8%, and the area under ROC curve was 0.962.Conclusion The binary classification logistic regression model has a good diagnostic efficacy in the diagnosis of benign and malignant axillary lymph nodes,while real-time elastography can improve the accuracy of conventional ultrasound in the diagnosis of axillary lymph nodes.

OBJECTIVETo establish the unitive multicomponent quality system bridged macrostate mathematic model parameters of material quality and microstate component concentration for Chinese materia medica (CMM).

METHODAccording to law of biologic laws of thermodynamics, the state functions of macrostate qulity of the CMM were established. The validation test was carried out as modeling drug as alcohol extract of Radix Rhozome (AERR), their enthalpy of combustion was determined, and entropy and the capability of information by chromatographic fingerprint were assayed, and then the biologic apparent macrostate parameters were calculated.

RESULTThe biologic macrostate mathematic models, for the CMM quality controll, were established as parameters as the apparent equilibrium constant, biologic enthalpy, Gibbs free energy and biologic entropy etc. The total molarity for the 10 batchs of AERR were 0.153 4 mmol x g(-1) with 28.26% of RSD, with the average of apparent equilibrium constants, biologic enthalpy, Gibbs free energy and biologic entropy were 0.039 65, 8 005 J x mol(-1), -2.408 x 10(7) J x mol(-1) and - 8.078 x 10(4) J x K(-1) with RSD as 6.020%, 1.860%, 42.32% and 42.31%, respectively.

CONCLUSIONThe macrostate quality models for CMM can represent their intrinsic quality for multicomponent dynamic system such as the CMM, to manifest out as if the forest away from or tree near from to see it.

Drugs, Chinese Herbal ; analysis ; Materia Medica ; analysis ; Models, Theoretical ; Quality Control ; Thermodynamics

Objective To investigate the correlation between long non-coding RNA (lncRNA)-LOC391533 and inadequate placental spiral artery remodeling in severe preeclampsia (sPE).Methods Thirty-six gravidas who were admitted to the Third Affiliated Hospital of Zhengzhou University with sPE from January 2016 to December 2016 were enrolled in sPE group.An equal number of healthy gravidas who experienced uneventful pregnancy and were of similar age (difference less than two years) and gestational age (difference less than one week) to those in the sPE group served as controls.Scanning electron microscopy was used to measure the luminal area and vessel wall thickness of placental spiral arteries for all gravidas.Levels of vascular endothelial growth factor (VEGF) and soluble VEGF receptor-1 (sVEGFR-1) in placenta tissues and maternal serum samples were detected by Western blot and ELISA.Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of LOC391533 at mRNA level in placenta tissues of the two groups.Independent two samples t-test,Mann-Whitney U test and Spearman correlation analysis were used for statistical analysis.Results (1) The average luminal area of spiral arteries of the sPE group was smaller than that of the control group [(130.1 22.3) vs (188.1 ±21.5) μ m2,t=10.888,P＜0.05],but the average thickness of spiral artery wall was thicker [(122.619.5) vs (98.9±2.5) μ m,t=-8.812,P＜0.05].(2) Compared with the control group,the sPE group showed increased sVEGFR-1 at protein level in both placenta tissues and serum samples [placenta:0.2±0.0 vs 0.4±0.1,serum:(15.6±2.4) vs (50.8±6.1) ng/L,t=-17.569 and-30.699,both P＜0.05],decreased VEGF at protein level in both placenta tissues and serum samples [placenta:0.6 ± 0.1 vs 0.2±0.0,serum:(40.8±3.2) vs (28.1 ±3.2) ng/L,t=18.013 and 16.200,both P＜0.05],and enhanced expression of LOC391533 at mRNA level in placenta tissues (1.00.2 vs 2.40.5,t=-14.799,P＜0.05).(3) Expression of LOC391533 at mRNA level in placenta tissues of the sPE group was positively correlated with spiral artery wall thickness and levels of sVEGFR-1 protein in placenta tissues and serum (r=0.683,0.759 and 0.857,all P＜0.05),and negatively correlated with luminal area and levels of VEGF protein in placenta tissues and serum (r=-0.702,-0.806 and-0.796,all P＜0.05).Conclusions Abnormal expression of VEGF and sVEGF-1 in placenta and serum of patients with sPE may be related to inadequate placental spiral artery remodeling.

Objective To investigate the antimicrobial resistance profile of the Streptococcus pneumoniae strains isolated from respiratory tract of children in Zhongshan Boai Hospital, Guangdong Province for better management of such infections. Methods The sputum samples were collected from respiratory tract of children in pediatric outpatient and inpatient from May 2013 to August 2017. S. pneumoniae strains were isolated and identified and their susceptibility to antimicrobial agentswas determined. Results The prevalence of S. pneumoniae was 10.6％ (2 963/28 006) in the sputum samples. S. pneumoniae was mainly isolated from children under 6 years old, and relatively higher in winter and spring. About 43.0％ of the S. pneumoniae isolates was associated with mixed infection, especially Moraxella catarrhalis and Haemophilus influenzae. About 6.0％ of the S. pneumoniae isolates were non-susceptible to penicillin, 59.3％ non-susceptible to ceftriaxone, and more than 95％ non-susceptible to erythromycin, clindamycin or tetracycline. However, more than 95％ of the isolates were susceptible to chloramphenicol or ofloxacin. No S. pneumoniae isolate was found resistant to rifampin, linezolid or vancomycin. Conclusions The respiratory tract infection caused by S. pneumoniae of children is increasing year by year, which is associated with age, season, and higher rate of mixed infection. These data showed that penicillin non-susceptible S. pneumoniae is highly prevalent in Zhongshan. More than 95％ of the S. pneumoniae isolates from children are resistant to erythromycin, clindamycin or tetracycline. S. pneumoniae isolates should be closely monitored for the emergence of multidrug resistant strains. Appropriate control measures must be taken according to the results of susceptibility testing.

Objective To systematically analyze and identify key risk factors for postoperative pulmonary hemorrhage u-sing a combination of the random forest(RF)model and traditional logistic regression analysis,so as to provide data support for clinical practice.Methods This study included patients who underwent needle biopsy of lung masses from January 2020 to December 2023 in the Department of Interventional Therapy,Cancer Hospital,Tianjin Medical University.There were 844 cases,including 387 males and 457 females,ranging in age from 39 to 82 years.Clinical data and puncture-related characteristics were collected,including tumor size,puncture depth,puncture angle,presence of emphysema,lesion loca-tion in the lung,body position during puncture,whether the puncture passed through the interlobar fissure,and the number of punctures.The RF model was used to rank the importance of all variables,identifying those with the highest predictive value.Subsequently,a multivariate logistic regression model was applied to the top-ranked important variables to further e-valuate their independent impact on postoperative pulmonary hemorrhage.Results The RF model results showed that tumor size and puncture depth had the highest importance in predicting the risk of postoperative pulmonary hemorrhage.Multivari-ate logistic regression analysis further confirmed that smaller tumor size(HR:0.980,95％CI:0.971-0.989,P＜0.05)was significantly associated with a lower risk of hemorrhage,while greater puncture depth(HR:1.146,95％CI:1.063-1.235,P＜0.05)was closely related to a higher risk of hemorrhage.Additionally,other factors such as puncture angle,age,lesion location in the lung and presence of emphysema showed some influence but did not reach statistical significance in the multi-variate analysis.Conclusion This study successfully identified tumor size and puncture depth as independent risk factors for postoperative pulmonary hemorrhage by combining the RF model with multivariate logistic regression analysis.The appli-cation of the RF model improved the accuracy of feature selection,allowing us to focus on the most contributory predictive variables.These findings provide important support for preoperative risk assessment,suggesting that clinicians should priori-tize these key factors in preoperative evaluations to develop safer and more effective surgical plans,thereby reducing the risk of postoperative hemorrhage and other complications.