ABSTRACT
Objective@#To investigate current status and associated factors of preschool children’s physical fitness, in order to provide scientific basis for improving preschool children’s physical fitness.@*Methods@#A total of 3 240 preschool children aged 3-6 years old in Kunshan city were selected through cluster sampling method. They were surveyed about physical fitness and influencing factors.@*Results@#The number of excellence of preschool children’s physical fitness was 269, and the rate was 8.30 percent. The excellence rates of preschool children’s physical fitness in girls, high grade, non-residency in Jiangsu Province were higher(10.87%, 10.96%, 14.88%), and the excellence rate of preschool children’s physical fitness in premature group was lower(4.31%)(P<0.05). Further unconditioned logistic regression analysis found that girls, middle and high grade and non-residency in Jiangsu Province were the protective factors for the excellence of preschool children’s physical fitness, OR values were 1.96, 1.94, 2.45 and 1.87, respectively; premature was a risk factor for the excellence of preschool children’s physical fitness, OR value was 0.47.@*Conclusion@#Preschool children in Kunshan have poor physical fitness, especially in boys, low grade and premature groups. Education department and health department should work together to improve the preschool children’s physical fitness.
ABSTRACT
Objective To study the expression level of thyroid insulin-like growth factor-Ⅰ (IGF-Ⅰ) in iodine deficiency and excess mice and the effect of thyroid gland IGF-Ⅰ in the thyroid morphological change. Methods Forty-eight Balb/c mice were chosen as studied objects,weighing about 16 g. They were divided into three groups: low iodine(LI,iodine content of 50 μg/kg in feed,drinking deironized water) group,normoi(NI,iodine content of 300 μg/kg in feed,drinking deironized water) group and high(HI,iodine content of 300 μg/kg in feed,iodoine of content 14 700 μg/kg in drinking) group,16 mice in each group. Mice were put to death after 12 weeks and taken out of their thyroid gland. The body weight,absolute and relative weights of thyroid gland were measured and the morphological change of thyroid gland were observed under microscope. The expression levels of thyroid gland IGF-Ⅰ mRNA and protein were detected by RT-PCR and immunohistochemistry,respectively. Results There were statistical significances between groups of thyroid absolute and relative weights(F = 315.881,405.921,all P < 0.01). LI group [(10.71±4.03) mg,(44.98±15.39)mg/100 g body weight]and HI group [(3.42±1.17)mg,(13.50± 3.89)mg/100 g body weight]had heavier thyroid absolute and relative weights than NI group[(2.11±0.53)mg,(8.35±1.98)mg/100 g body weight,all P < 0.01]. Under microscopy,the thyroid follicle capacity grew down and the follicle quantity grew up in LI group,the epithelium was stylolitic,the colloid diminished or absence in follicular cavity,while HI group presented colloid accumulation without follicular hyperplasia. The expression level of thyroid gland IGF-Ⅰ mRNA in LI group(1.03±0.32) was more than that in NI(0.65±0.19) and HI(0.59± 0.20) groups(F= 7.518,P< 0.01). In contrast to NI,there was no difference in the expression level of thyroid gland IGF-Ⅰ mRNA in HI group(P > 0.05). The brownish particles of LI group were more than NI and HI groups in the thyroid follicle epithelium by immunohistochemistry,while HI group was less than NI group. Conclusions The mice of iodine deficiency presented follicular hyperplasia goiter,the mice of iodine excess presented colloid accumulative goiter. The change of IGF-Ⅰ mRNA and protein expression may participate morphologleal change,indicating autocrine IGF-Ⅰ of thyroid gland may play an important role in regulating goiter formation.