Objective To study the overweight and obesity situation among Mongolian ethnic children and adolescents in the last 25 years and to provide a basis on related prevention and control measures.Methods A cross-sectional study was used,with 18 366 aged 7 to 18 Mongolian ethnic children and adolescents involved.Surveys on their physical health,in 1985,2000 and 2010 were carried out.Comparison on the mean of BMI and the prevalence rates of overweight and obesity in different years,genders,location of residence (urban or rural) was also made.Results Over the past 25 years,among the aged 7 to 18 Mongolian ethnic children and adolescents,the overall trend on their means of BMI was increasing.The prevalence rates of overweight and obesity in Mongolian ethnic children and adolescents were 2.1％,0.5％ in 1985,and 6.3％,2.4％ in 2000,with an increase of 2 to 4 times during the last 15 years.The prevalence rates of overweight and obesity were substantially increasing in the year 2010,to have reached 9.1％ and 6.6％,which were 4 to 12 times of the figures in 1985.The detection rates of overweight and obesity in urban boys were 1.2％,0 in 1985,7.9％,3.4％ in 2000 and 11.0％,11.8％ in 2010.However,the rate of obesity in the rural boys were 0.6％ and 0.6％ in 1985,2.8％,2.1％ in 2000 and 9.0％,3.4％ in 2010.In 1985 the rates of overweight and obesity in urban girls were 1.8％,0.3％,8.1％,4.3％ in 2000 and 9.4％,8.4％ in 2010.However,among the rural girls,the prevalence rates of overweight and obesity prevalence was 8.8％,2.2％ in 1985,4.5％,0.9％,in 2000 and 10.2％,4.5％ in 2010.The rates of overweight and obesity among groups in different years showed significant differences (P＜0.05).Conclusion Over the past 25 years,the prevalence rates on overweight and obesity increased significantly in Mongolian ethnic children and adolescents,and continued to rise,which called for reasonable and effective measures to be taken to prevent and control the occurrence of the problem.

OBJECTIVETo detect and study the types of Borrelia burgdorferi sensu lato in ticks and rodents from Da Xing-An Mountains Forest areas of China.

METHODSNested PCR was performed to amplify 5S-23S rRNA intergenic spacer of B. burgdorferi. Positive products were analysed by restriction fragment length polymorphism (RFLP) and single strand conformation polymorphism (SSCP), specimens showing unique RFLP profile were sequenced and analysed.

RESULTS1336 Ixodes persulcatus, 144 Dermacento silvarum, 144 Haemaphysalis concinna and 145 rodents of 9 species were collected from 16 sections of Da Xing-An Mountains Forest areas of China. Specific fragments were amplified from 293 I. persulcatus and 6 D. silvarum and 5 rodents of 4 species. B. burgdorferi was not detected in H. concinna. Among the positively tested I. persulcatus, 209 contained B. garinii genospecies and 45 contained B.afzelii genospecies based on RFLP. Moreover, B.garinii genospecies consisted of B. garinii 20047 and B. garinii NT29. 17 adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. garinii NT29. Nine adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. afzelii. Four adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. garinii NT29 and B. afzelii. Two D. silvarum were infected with B. garinii 20047, 1 D. silvarum with B. garinii 20047, 2 D. silvarum with B. afzelii. 3 rodents were infected with B. garinii 20047 while 2 rodents were infected with B. garinii NT29. Mixed infection was not found in D. silvarum and rodents. In addition, nine I. persulcatus and one D. silvarum specimens showed unique RFLP pattern. Data from sequential analysis showed that they all belonged to B. garinii. PCR-SSCP profiles of 5S-23S rRNA intergenic spacer of B. burgdorferi in the positive specimens exceeded 36 types; B. garinii 20047 showed 16 types while B. garinii NT29 showing 11 types, B. afzelii showing 9 types. SSCP profiles of the specimens coinfected with multiple B. burgdorferi was relatively complex.

CONCLUSIONThe infection of B. burgdorferi was found in the ticks and rodents in Da Xing-An Mountains Forests areas. The infection rate of I. persulcatus was high. B. garinii was predominant genospecies, and the population of B. burgdorferi was heterogeneous in the area. Mixed infections of different B. burgdorferi genospecies in ticks were found. I. persulcatus and Clethrionomys rufocanus were possibly served as major vector and major host for B. burgdorferi, respectively, suggesting that further study is needed to confirm the coinfection in humans and animals in this region.

Animals ; Borrelia burgdorferi Group ; genetics ; isolation & purification ; China ; epidemiology ; Humans ; Lyme Disease ; epidemiology ; Polymorphism, Restriction Fragment Length ; Polymorphism, Single-Stranded Conformational ; RNA, Bacterial ; analysis ; Rodentia ; microbiology ; Ticks ; microbiology ; Trees