Application of a support vector regression on prediction of bacillary dysentery combined with meteorological and air pollutants index / 中华疾病控制杂志

Objective To explore the application of support vector regression (SVR) model combined with meteorological and air pollutants index in the prediction of the cases of bacillary dysentery in Lanzhou City, so as to provide scientific reference for the prevention and control of bacillary dysentery.Methods Time series data of the reported cases of bacillary dysentery from December 2013 to August 2016, combined with the meteorological and air pollutants data, were used as training set to fit support vector regression model. The data from September 2016 to December 2017 was used as validation set to verify the model and compare the effect in fit and prediction with different models. Results A total of 7 192 bacillary dysentery cases were reported in Lanzhou City from 2013 to 2017. The correlation coefficient of meteorological and pollution factors with the cases of bacillary dysentery was more than 0.4, except air pressure. The parameters of the fit model were selected based on the integrated data, acquiring the three parameters with the smallest test error were C=5, γ=0.02 and ε=0.000 1, respectively. The validation set was used to test the different models, which showed that the integrated data model had the best predictive accuracy and robustness . The root mean squared error (RMSE) was 0.164 7 and the mean absolute percentage error (MAPE) was 16.405%. Conclusion SVR model combined with meteorological and air pollutants index is effective in the prediction of bacterial dysentery.

Application and comparison of residual autoregressive model and Holt’s two-parameter exponential smoothing model in infant mortality prediction in some countries along the Belt and Road Initiative / 中华疾病控制杂志

@# Objective To explore the application of residual autoregressive model and Holt's two-parameter exponential model in the prediction of infant mortality rate in some countries along the “Belt and Road” (China-Indo-China Peninsula Economic Corridor). Methods The time series data of infant mortality rate in Vietnam, Laos, Cambodia, Myanmar, Thailand, Singapore, Malaysia, and China for 1978-2013 were used as training set to fit residual autoregressive model and Holt's two-parameter exponential model. The 2014-2016 data was used as the validation set to compare the performance of model prediction. Results The akaike information criterion (AIC) value of the residual autoregressive model was superior to Holt's two-parameter exponential model. Both prediction models showed high accuracy, and most evaluation indicators (absolute error and relative error) of residual autoregressive prediction model were smaller than Holt's two-parameter exponential model. The residual autoregressive models of Laos, Myanmar and Cambodia were better than the Holt’s two-parameter exponential model for the infant mortality rate(IMR) prediction in different years. Conclusions The residual autoregressive model and Holt's two-parameter exponential model performed well in infant mortality rate prediction in some countries along the China-Indo-china Peninsula Economic Corridor. The residual autoregressive model has better fitting effect. The residual autoregressive model for infant mortality prediction is superior to the Holt two-parameter exponential model in most countries in most years.

Expression of interleukin-17 and retinoid-related orphan nuclear receptor gamma t in cornea of experimental keratomycosis / 中华实验眼科杂志

Background In the past few decades,the balance of Th1/Th2 is often used to explain the immune mechanisms of fungal infection and fungal disease.More recently,a novel subset of CD4+ effector Th cells has been found to participate in anti-fungal infection response.However,whether Th17 is involved in the immune response in fungal keratitis is unclear up to now.Objective Present study was to investigate the expression change of Th17 type cytokine and its specific transcription factor,retinoid-related orphan nuclear receptor gamma t (RORγt),in the cornea of Fusarium solani keratitis.Methods Ninety-six clean BALB/c mice were divided into Fusarium solani keratitis model group and control group by randomized digital table.Fusarium solani keratitis models were established by epikeratophakia-assisted corneal epithelial erasion and interlayerly injection of 5 μl (1 × 106 CFU/ml) Fusarium solani solution in the right eyes,and the equal volume of PBS was injected in the same way in the control group.10％ KOH wet film was used to examine the fungal hyphea and funga strain was identified by inoculation.The corneas were examined under the slit lamp microscope 1 day,3,5,7 days after modeling and the inflammatory response was scored based on the criteria of Wu and Hu.The histopathological examination of corneas was performed in the time points above.Real time fluorescence quantitative PCR was used to detect the expression levels of interleukin-17 (IL-17) mRNA and RORγt mRNA in the corneas.The expression of IL-17 protein in the corneas was detected by ELISA.The use and raise of the mice followed the Statement of Association for Research in Vision and Ophthalmology.Results The inflammatory scores were 3.2±0.8,6.6± 1.1,9.4± 1.1 and 6.8±0.8 in 1 day,3,5,7 days after modeling,showing a significant difference among them (F =89.786,P =0.010).The inflammatory scores were higher in the third and seventh day than that in the first day (P＜0.05),but they were significantly lower than that in the fifth day (P＜0.05).The infiltration of inflammatory cells showed a coincident tendency with the score.The expressing levels of IL-17 mRNA (2-ΔΔCt) in the corneas were 4.12±0.73,20.72±1.81 and 14.16±1.88 in 3,5,7 days after modeling,with statistically significant differences in comparison with those in the control group (P＜0.01),and the expression level was significantly higher in the fifth day than those in the first,third and seventh day in the model group(P＜0.01).The expression levels of IL-17 protein (ng/g) were significantly increased 1 day,3,5,7 days in the model group compared with the control group (P＜0.01).A similar change was found in the expression of RORγt mRNA to that of IL-17 mRNA.Conclusions Expressions of IL-17 and its transcription factor RORγt upregulate in the fungal keratitis and has an association with inflammatory degree,which suggests that Th17 subset may play an important role in the immune responses of fungal keratitis.

Statistical analysis of residues of heavy metals in Chinese crude drugs / 中国中药杂志

<p><b>OBJECTIVE</b>To analyze the residues of heavy metals in Chinese crude drugs.</p><p><b>METHOD</b>The SPSS 13.0 software was used to analyze the data of Cu, Pb, As, Cd, Hg collected in literatures. And, Green Trade Standards of Importing & Exporting Medicinal Plants & Preparations was used as the standard to evaluate the pollution condition of Cu, Pb, As, Cd, Hg in Chinese crude drugs.</p><p><b>RESULT</b>Chinese crude drugs were contaminated by heavy metals in different levels. The content of Cu, Pb, As, Cd, Hg exceeded the limit of the standard and the percentage was 21.0%, 12.0%, 9.7%, 28.5%, 6.9%, respectively; the phenomena of two, three and four metals exceeding limited standard simultaneity in a drug were also found and the percentage was 4.6%, 1.5%, 0.7%, respectively; the content of heavy metals in Radix Platycodi, Radix Asari and Rhizoma Coptidis was higher among the thirty-six Chinese crude drugs; All of the content of five heavy metals in Barbary Fructus Lycii Rhizoma Anemones Raddeanae, Radix Panacis Quiquefolii and Fructus Aurantii were below the limit; The pollution levels of heavy metals in different locality were different; The content of Cu, Pb in cultivated Chinese crude drugs was higher than that in wild Chinese crude drugs, while the content of As in wild Chinese crude drugs was higher than that in cultivated Chinese crude drugs.</p><p><b>CONCLUSION</b>The pollution levels of heavy metals in Chinese crude drugs were detailed reported in this paper. And it provided ways for the further study of heavy metals in Chinese crude drugs.</p>

Study on the prognostic factors of colorectal cancer after radical resection and on suggested model for prediction / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the factors of colorectal cancer (CRC) after radical resection to provide data predicting the prognosis of the patients.</p><p><b>METHODS</b>120 cases of CRC were collected in this study. Medical clinical records and 5-year follow-up data were reviewed. Streptavidin-peroxidase immunohistochemical technique was used to detect the expression of p53, C-erbB-2, nm23-H(1) and Ras on formalin-fixed, paraffin embedded sections of CRC from the 120 patients.</p><p><b>RESULTS</b>Results showed that the rates of positive expression of p53, C-erbB-2, Ras and nm23-H(1) were 62.5% (75/120), 25.8% (31/120), 80.0% (96/120) and 60.8% (73/120) respectively in the CRC tissue. All pathological variables and biological markers were analyzed with Cox regression model (alpha = 0.05). Eight distinguished prognostic factors were identified in the univariate analysis as: macroscopic configuration, histology grade, depth of invasion of intestinal, lymph nodes metastasis, Dukes' classification, p53, Ras and nm23-H(1). The results of multivariate analysis (alpha = 0.05) indicated that the independent prognostic factors were Dukes' classification, p53 and nm23-H(1) (P = 0.000), with relative risk of 3.06, 6.02 and 0.40, respectively. A prognostic model: h(t, x) = h(0)(t)exp (-0.9269X(14) + 1.1197X(10) + 1.7948X(11)) was established. Sensitivity, specificity agreement and reliability of the model and Kappa were 79.1%, 83.0%, 80.8% and 0.62, respectively.</p><p><b>CONCLUSION</b>Dukes' classification, p53 and nm23-H(1)seemed to be independent and important prognostic factors. This prognostic model could be used to evaluate the prognosis of patients with CRC by clinicians.</p>