Application of ARIMA model to predict schistosomiasis cases in China / 中华地方病学杂志

Objective:An autoregressive integrated moving average (ARIMA) model was used to predict the number of monthly reported cases of schistosomiasis in China (excluding Hong Kong, Macao and Taiwan), so as to provide a scientific basis for prevention and control of schistosomiasis.Methods:Using ARIMA model, taking the time series of monthly reported cases of schistosomiasis in China from January 2009 to December 2018 as the training set, after stabilizing analysis with R 3.6.2 software, ARIMA models were selected by using screening parameters such as akaike information criterion and bayesian information criterion. Taking the number of monthly reported cases of schistosomiasis in China from January to December 2019 as the test set for verification and monthly optimization, an optimal ARIMA model was obtained. The prediction effect of the optimal ARIMA model was verified by the number of monthly reported cases of schistosomiasis in China from January 2019 to October 2020.Results:Based on the data of monthly reported cases of schistosomiasis in China from January 2009 to December 2018, four ARIMA models were obtained, namely ARIMA(2,0,2)(1,0,1)[12], ARIMA(2,0,2)(0,0,1)[12], ARIMA(2,0,2)(1,0,0)[12] and ARIMA(2,0,2). By comparing the actual number of cases from January to December 2019 with the predicted values of the four ARIMA models, the optimal prediction model of monthly reported cases of schistosomiasis was ARIMA(2,0,2)(1,0,1)[12], and the mean relative error of the prediction was 0.51%.Conclusions:The ARIMA model constructed in this study has high accuracy and is suitable for short-term prediction and analysis of the number of schistosomiasis cases in China. It can provide data support for prevention and control of the disease, and has certain practical guiding significance.

Effects of calcium supplementation during the pregnancy and early infancy stage on the body mass index and gut microbiota in the infants / 中华预防医学杂志

Objective@#To investigate the effects of calcium supplementation during the pregnancy and early infancy stage on body mass index (BMI) and gut microbiota in the infants.@*Methods@#A total of 1 752 healthy pregnant women and their infants (breast feeding) in two maternal and child health care hospitals of Beijing were chosen as the subjects in this study from May to October 2016. Questionnaires were used to obtain the general information and supplementation of calcium and vitamin D in mothers and their infants. The body length and weight of infants at birth and 6 months were recorded to calculate the BMI. The random number table method was used to randomly select 40 infants from each group for gut microbiota analysis (If less than 40 infants were all included in this study, 23 infants in the pregnancy and early infancy would be all treated with calcium supplements. There were 6 infants who was not added calcium during the pregnancy but added in the early infancy). Then it was compared that the effects of calcium supplementation during the pregnancy and early infancy on the BMI and gut microbiota composition of infants were determined at birth and 6 months.@*Results@#Compared to the group with no calcium supplementation during the pregnancy ((12.76±1.23), (17.68±0.76)kg/m2), the BMI of infants at birth and 6 months in the group with calcium supplementation during the pregnancy ((13.51±0.47), (17.91±0.23)kg/m2) were significantly higher(P<0.05). In the group with maternal calcium supplementation, the BMI at 6 months ((18.63±0.52)kg/m2), BMI increment ((5.71±0.54)kg/m2) and the content of lactobacillus (21.04%±3.68%) in the only calcium supplementation subgroup in the early infancy were higher than those in only vitamin D supplementation subgroup ((17.69±0.89) kg/m2, (4.17±1.01) kg/m2 and 12.28%±3.86%) (P<0.05). In the group without maternal calcium supplementation, the content of lactobacillus (20.15%±4.87%) in the only calcium supplementation subgroup were also higher than those in only vitamin D supplementation subgroup (14.64%±3.71%) (P<0.05).@*Conclusion@#Appropriate calcium supplementation during the pregnancy is good for the growth and development of the fetus. Calcium supplementation in the early infancy could increase the BMI of infants, and promote the growth of intestinal lactobacillus.

Effect of docosahexenoic acid supplementation on infant's growth and body mass index during maternal pregnancy / 中华流行病学杂志

Objective To investigate the effects of docosahexenoic acid (DHA) supplementation on infant's growth and BMI during pregnancy.Methods A total of 1 516 healthy pregnant women delivered their babies in two maternal and child health care hospitals in Beijing and were chosen as the subjects in this cohort study from May to October 2015.Self-developed questionnaires were used to gather general information of the subjects,including age,height,weight,weight gain during pregnancy,delivery mode,DHA supplementation etc.,before giving birth.Information on body length,weight,head circumference and BMI at birth and 6 months postnatal,of the infants were recorded.Breast milk was collected to test the fatty acid profiles by using the gas chromatography (GC) method at one to three months postnatally.Results The overall rate of DHA supplementation was 47.76％ among the pregnant women,in which introduction of DHA from the early and second stage of the pregnancy accounted for 49.31％ and 39.64％ respectively.When DHA supplementation began from the early pregnant stage,the DHA concentration showed an increase in the milk (P＜0.05),whereas the supplementation began from the second and third stages did not affect the milk DHA concentration (P＞0.05).Higher height and lower BMI were seen in the infants at birth and 6 months in the supplementation group when comparing to the non-supplementary group (P＜0.05),with the greatest effects noticed in the earliest supplementation group.Specifically,the head circumference appeared larger from the early pregnant stage in the DHA supplementary group,than that in the non-supplement group (P=0.001).The increment of head circumference was larger than that in the other groups when the infants were 6-month old (P＜0.01).Results from the partial regression analysis showed that during pregnancy,there were positive correlations between DHA supplementation and height (r=0.324,r=0.216),head circumference (r=0.221,r=0.302) as well as the increment of head circumference (r=0.276) at birth and 6 months (P＜0.05).Whereas,a negative correlation was shown between DHA and the infants' BMI (r=-0.310,r=-0.371) (P＜0.05) when supplementation was given during maternal pregnancy.Conclusions When DHA supplementation program was carried out during maternal pregnancy,it could increase the height and head circumference and inhibit the rapid increase of BMI in the infants BMI.Our findings seemed helpful in promoting brain development and preventing the childhood obesity.

Effect of docosahexenoic acid supplementation on infant's growth and body mass index during maternal pregnancy / 中华流行病学杂志

Objective To investigate the effects of docosahexenoic acid (DHA) supplementation on infant's growth and BMI during pregnancy.Methods A total of 1 516 healthy pregnant women delivered their babies in two maternal and child health care hospitals in Beijing and were chosen as the subjects in this cohort study from May to October 2015.Self-developed questionnaires were used to gather general information of the subjects,including age,height,weight,weight gain during pregnancy,delivery mode,DHA supplementation etc.,before giving birth.Information on body length,weight,head circumference and BMI at birth and 6 months postnatal,of the infants were recorded.Breast milk was collected to test the fatty acid profiles by using the gas chromatography (GC) method at one to three months postnatally.Results The overall rate of DHA supplementation was 47.76％ among the pregnant women,in which introduction of DHA from the early and second stage of the pregnancy accounted for 49.31％ and 39.64％ respectively.When DHA supplementation began from the early pregnant stage,the DHA concentration showed an increase in the milk (P＜0.05),whereas the supplementation began from the second and third stages did not affect the milk DHA concentration (P＞0.05).Higher height and lower BMI were seen in the infants at birth and 6 months in the supplementation group when comparing to the non-supplementary group (P＜0.05),with the greatest effects noticed in the earliest supplementation group.Specifically,the head circumference appeared larger from the early pregnant stage in the DHA supplementary group,than that in the non-supplement group (P=0.001).The increment of head circumference was larger than that in the other groups when the infants were 6-month old (P＜0.01).Results from the partial regression analysis showed that during pregnancy,there were positive correlations between DHA supplementation and height (r=0.324,r=0.216),head circumference (r=0.221,r=0.302) as well as the increment of head circumference (r=0.276) at birth and 6 months (P＜0.05).Whereas,a negative correlation was shown between DHA and the infants' BMI (r=-0.310,r=-0.371) (P＜0.05) when supplementation was given during maternal pregnancy.Conclusions When DHA supplementation program was carried out during maternal pregnancy,it could increase the height and head circumference and inhibit the rapid increase of BMI in the infants BMI.Our findings seemed helpful in promoting brain development and preventing the childhood obesity.

Experience and analysis of excellent works of human parasitology in nation-al medical colleges and universities / 中国血吸虫病防治杂志

Teaching competition is an effective way for college and university teachers to improve their teaching skills. Based on the teaching practice and experience in medical parasitology,this paper discusses several key issues in teaching competition including topics,teaching designs and teaching methods. It provides references for the teachers in department of parasitology of universities and colleges to improve the quality of classroom teaching.

Multiple insecticide resistances and kdr mutation of Culex pipiens pallens in north-central Anhui Province / 中国血吸虫病防治杂志

Objective To understand the status of resistance to multiple insecticides and the frequencies of kdr mutations in Culex pipiens pallens from north?central Anhui Province. Methods From July to September,2014,the C. pipiens pallens mosquito larvae were collected in Huaibei,Bengbu and Chuzhou cities of the north?central Anhui Province and reared to adults. The female adult mosquitoes at 3-5 days post emergence were tested for susceptibility to the four insecticides,namely 0.05%deltamethrin,5%malathion,0.1%bendiocarb and 4%DDT,by using the standard WHO resistance tube bioassay. The detec?tion of the point mutations of the kdr gene at codon 1014 was conducted by PCR and DNA sequencing in the deltamethrin?resis?tant and?susceptible mosquitoes. Results High levels of resistance to all the four insecticides were found in all the three tested populations,although mosquito mortality varied among populations and test insecticides. Among the test insecticides,DDT showed lowest mortality with no significant difference(F=1.027,P>0.05)in all test populations,whereas significantly differ?ent mortalities were observed among populations for the remained three insecticides tested(deltamethrin,malathion,and ben?diocarb)(F = 23.823,33.955,128.841;all P < 0.01). Two types of non?synonymous kdr mutation at codon position 1014 (L1014F and L1014S)were observed. A positive correlation between L1014F mutation frequencies and deltamethrin resistance levels were detected in the three mosquito populations(r2=0.718,P<0.01). Conclusions The observed high levels of resis?tance to multiple?insecticides coupled with the occurrence of medium to high kdr frequencies in populations of C. pipiens pallens could profoundly affect the mosquito vector control programme in China. The local health departments need to strengthen vector dynamic monitoring and implement rational resistance management strategies.

Analysis of population genetic structure of Anopheles sinensis based on mitochondrial DNA cytochrome oxidase subunit I gene fragment / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the population genetic variation, genetic diversity and phylogenesis of Anopheles sinensis in China.</p><p><b>METHODS</b>Anopheles sinensis samples collected from Shandong, Anhui, Jiangsu, Guizhou, and Yunnan Provinces and Guangxi Zhuang Autonomous Region with different geographical conditions between 2010 and 2012 were analyzed by mitochondrial DNA cytochrome oxidase subunit I (mtDNA-COI) gene amplification and sequencing. Bioedit 7.0 and DnaSP 5.0 software was used to compare the gene sequences and analyze the population genetic structure, respectively. Arlequin 3.1 was used to calculate the genetic distance and parameters of population differentiation. The relationship between the geographic and genetic distances was analyzed using IBD Web Service. PHYLIP 3.6 was used to construct the phylogenetic tree.</p><p><b>RESULTS</b>PCR amplification and sequencing was performed successfully for 6 Anopheles sinensis populations containing 123 female mosquitoes. The length of mtDNA-COI gene fragment was 841 bp with an average A+T content of 71.2% and G+C content of 28.8%. High nucleotide diversity and genetic differentiation were observed among the Anopheles sinensis populations based on mtDNA-COI gene. Analysis of the molecular variance revealed a greater variation between populations than that within populations with isolation by distance between the populations. The Anopheles sinensis populations appeared to have undergone expansion, but the Yunnan population constituted an isolated branch in the phylogenetic tree.</p><p><b>CONCLUSION</b>mtDNA-COI can serve as the molecular marker to analyze population genetic variation and phylogenesis of Anopheles sinensis. The Yunnan population shows a phylogenetic difference from the other populations analyzed in this study.</p>