Objective:To study the current status of longitudinal extrauterine growth restriction (EUGR) in extremely preterm infants (EPIs) and to develop a prediction model based on clinical data from multiple NICUs.Methods:From January 2017 to December 2018, EPIs admitted to 32 NICUs in North China were retrospectively studied. Their general conditions, nutritional support, complications during hospitalization and weight changes were reviewed. Weight loss between birth and discharge > 1SD was defined as longitudinal EUGR. The EPIs were assigned into longitudinal EUGR group and non-EUGR group and their nutritional support and weight changes were compared. The EPIs were randomly assigned into the training dataset and the validation dataset with a ratio of 7∶3. Univariate Cox regression analysis and multiple regression analysis were used in the training dataset to select the independent predictive factors. The best-fitting Nomogram model predicting longitudinal EUGR was established based on Akaike Information Criterion. The model was evaluated for discrimination efficacy, calibration and clinical decision curve analysis.Results:A total of 436 EPIs were included in this study, with a mean gestational age of (26.9±0.9) weeks and a birth weight of (989±171) g. The incidence of longitudinal EUGR was 82.3%(359/436). Seven variables (birth weight Z-score, weight loss, weight growth velocity, the proportion of breast milk ≥75% within 3 d before discharge, invasive mechanical ventilation ≥7 d, maternal antenatal corticosteroids use and bronchopulmonary dysplasia) were selected to establish the prediction model. The area under the receiver operating characteristic curve of the training dataset and the validation dataset were 0.870 (95% CI 0.820-0.920) and 0.879 (95% CI 0.815-0.942), suggesting good discrimination efficacy. The calibration curve indicated a good fit of the model ( P>0.05). The decision curve analysis showed positive net benefits at all thresholds. Conclusions:Currently, EPIs have a high incidence of longitudinal EUGR. The prediction model is helpful for early identification and intervention for EPIs with higher risks of longitudinal EUGR. It is necessary to expand the sample size and conduct prospective studies to optimize and validate the prediction model in the future.

Objective: To evaluate the distribution characteristics and health risk of trichloromethane (TCM) in the drinking water supply of primary and middle schools in rural areas of Tianjin, so as to provide a scientific basis for improving drinking water safety in rural schools. Methods: A total of 60 water samples from 30 rural primary and middle schools in 10 agricultural districts of Tianjin were collected from April to June (dry season) and July to October (wet season) in 2023 with direct selection method. The content of TCM was detected according to the Standard Methods for the Examination of Drinking Water, and a risk assessment method recommended by the United States Environmental Protection Agency was used to evaluate the health risk of TCM through oral exposure. Results: The concentration of TCM in drinking water was no detection to 54.00 μg/L, with an average of (13.44±14.88) μg/L, and the value was higher during the wet season [12.90(1.40,32.28)μg/L] than the dry season [2.40(1.40,18.13)μg/L] (Z=-2.09, P<0.05). The concentration of TCM for primary and middle schools were [3.38(1.40,20.75) μg/L] and [5.30(1.40,28.23)μg/L] respectively, and there was no statistically significant difference between different types of schools (Z=0.50, P>0.05). The carcinogenic risk through oral exposure ranged from 3.84×10-7 to 2.05×10-5, while the noncarcinogenic risk ranged from (0.00-0.16), all within the acceptable range. Children aged 6 to 9 years old were at the highest risk. Conclusions TCM has been detected in the drinking water of rural primary and middle schools to a certain extent in Tianjin, and attention should be paid to the potential health risks of oral exposure. The monitoring and management of disinfection byproducts in drinking water should be strengthened to further reduce the risk of exposure to children.

Objective:To investigate the myocardial protective effect of extracorporeal cardiac shock wave therapy (CSWT) combined with sulfur hexafluoride microbubble post-conditioning on myocardial ischemia-reperfusion injury (MI/RI) in rats, and to provide theoretical support for clinical treatment of MI/RI.Methods:A total of 32 male SD rats were randomly divided into 4 groups: sham operation group (Sham group), MI/RI group (IR group), CSWT group (IR+ SW group), and CSWT combined with sulfur hexafluoride microbubble treatment group (IR+ SW+ MB group), with 8 rats in each group. Therapeutic intervention was performed in IR+ SW group and IR+ SW+ MB group on the 1st, 3rd and 5th day after modeling. The left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) of the rats were measured by echocardiography before and after treatment. On the 7th day, myocardial fibrosis was assessed by Masson staining, and cardiomyocyte apoptosis was observed by TUNEL staining. The myocardial apoptotic proteins Bcl-2, BAX, Cleaved-Caspase-3 and Cleaved-Caspase-9 in the infarct boundary area were detected by Western blot. The differences of the above indexes among different groups were compared.Results:①There was no significant change in heart rhythm and heart rate among the groups before and after treatment, and there was no significant difference in heart rate ( P>0.05). ②The echocardiographic results after treatment showed that, compared with IR group, LVEDD and LVESD in IR+ SW group and IR+ SW+ MB group decreased in turn, while LVEF and LVFS increased in turn with significant differences between each two groups (all P<0.05). ③Compared with IR group, the degrees of myocardial fibrosis and apoptosis in IR+ SW group and IR+ SW+ MB group were alleviated in turn, and the relief in IR+ SW+ MB group was the most obvious. Quantitative analysis showed that compared with IR group, the proportions of cardiomyocyte apoptosis in IR+ SW group and IR+ SW+ MB group decreased in turn, and there were significant differences between each two groups (all P<0.05). ④The results of Western blot detection showed that compared with IR group, the levels of Bcl-2 in IR+ SW group and IR+ SW+ MB group increased in turn, while the levels of BAX and the activation level of Caspase-3 and Caspase-9 protein decreased in turn. These differences were all statistically significant between each two groups (all P<0.05) except for the activation level of Caspase-3 protein between IR+ SW group and IR+ SW+ MB group ( P>0.05). Conclusions:CSWT combined with sulfur hexafluoride microbubble therapy can improve left ventricular remodeling and left ventricular systolic function by inhibiting cardiomyocyte apoptosis.

Multidrug resistance （MDR） has been a main culprit behind the failure of chemotherapy in patients with malignant tumors and a major obstacle to improving the life quality and prolonging the survival of patients. Hepatocellular carcinoma cells， the innate drug-resistant cells， are generally insensitive to radiotherapy and chemotherapy. Moreover， as the early symptoms of hepatocellular carcinoma are atypical， most patients are diagnosed at the advanced stage， with short survival period and high recurrence rate. Thus， the sensitivity to chemotherapy drugs is decreased. This explains how MDR becomes one of the important reasons for the failure of primary hepatocellular carcinoma （PHC） treatment. Therefore， it is an urgent task to search for safe and effective chemosensitizers with little adverse effect in the research on the drug resistance of hepatocellular carcinoma. As Chinese medicine has been widely applied in the treatment of tumors， the mechanisms of compound Chinese medicine prescriptions， Chinese medicine injections， and single Chinese medicinal in reversing chemotherapy resistance in liver cancer have attracted the interest of scholars. According to previous reports， the mechanisms can be summarized as increasing intracellular drug concentration， influencing changes in enzyme activity， inducing apoptosis， reversing abnormalities in cellular signaling pathways， and regulating the tumor microenvironment. Traditional Chinese medicine reduces the chemotherapy resistance of hepatocellular carcinoma cells through multiple targets and multiple pathways， thereby improving the chemotherapy sensitivity of the cancer cells and enhancing the toxicity of chemotherapeutic drugs to hepatocellular carcinoma cells. Therefore， exploring the mechanism of MDR of hepatocellular carcinoma from the perspective of traditional Chinese medicine is important for reversing the MDR and is of great reference value for clinical treatment of hepatocellular carcinoma. However， there are few experimental types and adverse effects available. Thus， the multi-mechanism and multi-target experiments and clinical research should be carried out in the future.

Objective:To explore the feasibility of dual-energy CT (DECT) in the evaluation of liver iodine concentration in patients on long-term oral amiodarone treatment (≥12 months).Methods:Eighteen subjects undergoing abdominal dual-energy CT who met the criterion in January 2017 were collected as a control group. Twenty-seven patients who received oral amiodarone treatment for more than 12 months from January 2017 to May 2019 were enrolled as an experimental group. The difference of CT value and iodine concentration of liver, pancreas and spleen in 140 kV, 100 kV and VNC images between experimental and control groups were measured and analyzed. The correlation between liver CT value and liver iodine concentration was analyzed by Spearman correlation.Results:The concentrations of iodine in the liver, pancreas and spleen of the experimental group were 0.2 (0.2, 0.4), 0.1 (0.1, 0.2) and 0.2 (0.1, 0.2) mg/ml, and those in the control group were 0.2 (0.1， 0.2), 0.1 (0.1, 0.2) and 0.1 (0.1, 0.2) mg/ml. The difference in the concentration of iodine of the liver was statistically significant ( Z=-3.354, P<0.05), however there was no significant difference in the concentration of pancreas and spleen between the two groups ( Z=-0.179 and -1.590, P>0.05). The CT values of 100 kV, 140 kV, VNC images in the experimental group [(74±18)， (70±10) and (71±5) HU] were higher than those in the control group [(60±6)， (59±6) and (62±6) HU], and the differences were statistically significant ( t=3.310, 4.205 and 5.241, P<0.05). There was a positive correlation between the CT value of 140 kV image and iodine concentration ( r=0.410, P<0.05). In the experimental group, the time difference of taking amiodarone was statistically significant ( P<0.05). Conclusions:DECT can be used to quantitatively measure the liver iodine concentration of patients with long-term oral amiodarone, and provides some biological indicators for the assessment of amiodarone induced liver injury.

Objective To assess the diagnostic value of 3D-enhanced T2 ? weighted angiography (ESWAN )in evaluating superficial siderosis of the central nervous system (SS-CNS)after traumatic subarachnoid hemorrhage (tSAH).Methods ESWAN and GRE T2 ? WI sequence were performed on 30 patients with tSAH,detection rate and the number of distribution areas of SS-CNS were compared between the two sequences.A McNemar’s test and Wilcoxon signed-rank test were used to analyze the differences between T2 ? WI and ESWAN images sequences. Results In the tSAH group,29 of 30 patients (96.7%)showed SS-CNS on ESWAN images,the total number of SS-CNS regions was 134.Identified SS-CNS positive rate respectively was 95.8% (23/24)on ESWAN images and 66.7% (1 6/24)on T2 ? WI in 24 patients simultaneously perform ESWAN and T2 ? WI sequences.A McNemar ’s test showed that there was significant difference between the positive rates of two sequences in detecting the SS-CNS (χ2 =7.0,P <0.05).The number of SS-CNS regions on ESWAN images and T2 ? WI was 106 and 34 respectively.The Wilcoxon signed rank test showed that the number of SS-CNS regions difference between two sequences was significant (Z =-4.225,P <0.01).Conclusion Various degress of SS-CNS are detected in a majority of tSAH atients.ESWAN sequence is a reliable and efficient method for assessment of SS-CNS.

Objective To investigate the risk factors for drug resistance‐tuberculosis(DR‐TB) ,and to establish a clinical risk predictive model .Methods A total of 126 cases of DR‐TB patients and 126 cases of non‐DR‐TB patients treated in our hospital from January 2014 to January 2015 were included in this study .The clinical data of these patients were collected .We used univariate and multivariate logistic regression analysis to determine the independent risk factors and established a risk predictive model .The calibration and discrimination of the model were assessed by the H‐L test and the area under the ROC curve ,respectively .Results Statistical analysis showed that the risk factors included previous treatment ,a duration of first treatment of more than 8 months ,ad‐verse effects of anti‐TB medication ,more than three TB foci in the lung and diabetes mellitus .H‐L statistic(χ2 =8 .760 ,P=0 .363) . The area under the ROC was 0 .826 ,95% CI(0 .766 ,0 .886) .Conclusion Logistic regression model established in the study can pre‐dict the incidence of DR‐TB with high prediction accuracy .

Objective To investigate microRNAs ( miRNAs) expression profiling of cardiomyocytes in rats with heart failure, and predict miRNAs-regulated target genes and their functions.Methods Total of 18 male SD rats weighing 200-220 g were randomly divided into 2 groups:the control group ( CON) and the heart failure group (HF).The rats in HF group were injected by adriamycin via tail vein to induce heart failure, meanwhile in CON group, rats were received an equal volume of 0.9% sodium chloride intravenously.The cardiomyocytes isolated from the rat hearts in two groups and cultured overnight.After that, total RNA was extracted and then subjected to miRNA microarray to screen differentially expressed miRNAs.The reults of microarray were further verified by quantitative real-time PCR ( qRT-PCR ) .The target genes regulated by differentially expressed miRNAs were predicted by the software of Targetscan and miRanda.Bioinformatics analysis was performed to predict the miRNAs-regulated target genes and analyze the enriched gene ontology ( GO) and signaling pathway ( KEGG Pathway) .Results The results of miRNA microarray showed that a total of 37 miRNAs were differentially expressed in HF group as compared to CON group, among which 22 miRNAs were up-regulated and 15 miRNAs were down-regulated (P<0.01, FDR<0.05).The expression of miR-133b-5p (t=14.56, P<0.01), miR-6216 (t=9.32, P<0.01) and let-7e-5p (t=13.92, P<0.01) which were detected by qRT-PCR exhibited the similar tendency of up or down regulation to those shown in microarray results.Bioinformatics analysis indicated that miRNAs-regulated target genes were significantly enriched in 31 GOs (P<0.01, FDR<0.05) and 12 signal pathways (P<0.05, FDR<0.05), among which ubiquitin-proteasome system, MAPK signaling pathway and Toll like siganling pathway exhibited a higher enrichment. Conclusion MiRNA expression profile on cardiomyocytes in rat with adriamycin-induced heart failure was significantly changed.These differentially expressed miRNAs might participate in the process of heart failing by regulating their target genes in rat cardiomyocytes.

Objective To investigate the adverse effect of different doses of high power microwave(HPM) irradiation on oxidative stress in the brain of Wistar rats in order to contribute to establishing an animal model to evaluate protective agents which will be used for protection against microwave radiation.Methods Eighty male Wistar rats were randomly divided into 16 groups according to factor analysis.The average power density was 0,10,30 and 100 mW/cm2 and the sampling time was 6 h,1,3 and 7 d .The duration of exposure was 6 minutes for each radiation group.After exposure, the rats were sacrificed at each sampling time.Colorimetric method was used to measure the content of malondialdehyde(MDA) and protein carbonyl, the activity of GSH-px, SOD and CAT.Results The content of MDA and protein carbonyl of each radiation group was increased with the radiation dose, but decreased with the sampling time prolonged.The activity of superoxide dismutast(SOD),glutathion peroxidase(GSH-px) and catalase(CAT) in each radiation group was decreased with the radiation dose increased, and with the sampling time prolonged, but increased later.Conclusion Microwave radiation can cause oxidative stress in rats brain, as shown by the oxidative damage of lipid and protein and the decrease in the activity of antioxidant enzymes.Besides, the effect also depends on the radiation dose and sampling time.

Objective To explore the development of disaster nursing in undergraduate courses . Methods Measures were done in writing program , course design , textbook writing , determining the content , theoretical teaching and experimental teaching .Results In 2012, 51 among 60 students (85.00%) selected the course of disaster nursing .In 2013, 40 among 60 students ( 66.67%) selected the course of disaster nursing.During the two years of course development , 75.83% students selected the disaster nursing courses . The class hour increased from 24 to 30 .The textbook of disaster nursing was edited and published as the nursing teaching materials of the twelfth five-year plan .Conclusions It is necessary to develop the disaster nursing in undergraduate education .We recommend promoting the disaster nursing in medical colleges and universities .