Objective To evaluate the effects of iodine on antioxidative capability by observing activity of antioxidative enzymes and related gene expression, and peroxide content in the brain of rat offspring. Methods One-month weaning Wistar rats were divided into four groups(low iodine-LI, normal iodine-NI, ten-fold high iodine-10HI and fifty-fold high iodine-50HI), and fed with water containing different iodine concentration by adding potassium iodate respectively. Rats mate randomly after three months.The offspring were sacrificed at 28 days after birth, then the activity of SOD and GSH-Px, and MDA content in brain tissue were tested, and the SOD and GSH-Px mRNA expression were measured by RT-PCR. Results Compared with the NI group, only in LI group MDA content were increased significantly (P

Objective To study the effect of different dosage KIO3 on anti-oxidative capability of the blood.Methods The Wistar rats were randomly divided into 6 groups and given KIO3 through food at different dosages,low iodide(LI),normal iodide(NI),5 fold high iodide(5HI),10 fold high iodide(10HI),50 fold high iodide(50HI)and 100 fold high iodide(100HI).3,6 and 12 months later,the rats were sacrificed and blood glutathione peroxidase(GPx)activity,superoxide dismutase(SOD)activity and malondialdehyde(MDA)content were determined.Results After 3,6 and 12 months of treatment,the GPx activity in LI group was significantly lower than that in NI group.Furthermore,after 12 months of low iodide intake,the SOD activity in LI group was higher than that in NI group.The GPx activity in 100HI group was lower than that in NI group after 3 months of administration,but no difference was seen between these two groups after 6 and 12 months of treatment.No difference was found in the GPx activity of NI group and those of 5HI,10HI and 50HI groups.The SOD activity in 50HI and 100HI groups was higher than that in NI group after 12 months of administration.There was no difference in MDA content among NI group and 4 high iodide groups.Conclusion Low iodide intake may damage the anti-oxidative capability of blood in normal rats.Blood has a strong anti-oxidative ability and compensative capabilities to compete with high iodate intake.

Objective To explore the effects of iodine on apoptosis and proliferation of the thyroid cells. Methods Wistar rats of one month wean were randomly divided into five groups(low iodine-LI, normal iodine-NI, fivefold high iodine-5 HI, tenfold high iodine-10 HI, fiftyfold high iodine-50 HI), and fed on water containing different concentration of iodine. All groups got prospective iodine intake, that is 0.6, 6.15, 30.75, 61.5, and 307.5 mg/d. After 7 days, 14 days, 28 days, the rats were sacrificed. The proliferation, apoptosis, and apoptosis related genes expression in the thyroid cells were determined by TUNEL, immunohistochemistry and RT-PCR. Results As for short-term of iodine deficiency, no significant change was seen in the mRNA expression of fas and fasL genes, while in the iodine excess groups,the expreesion showed an up-regulation trend as iodine intake increased. Fas and FasL proteins expressions were consistent in LI and NI groups and all of them were negative or weak positive. In the HI groups the stain density increased with iodine intake and treatmnet period increased. Expression of PCNA was enhanced by short-term iodine deficiency, but not by short-term iodine excess. Apoptosis was not observed in all groups. Conclusion Both short-term iodine deficiency and iodine excess have no obvious effects on thyrocytes apoptosis. Proliferation can be induced by short-term iodine deficiency, not by iodine excess. Wistar rats present a strong tolerance to long-term iodine excess.

Objective To study the effects of excessive iodine intake through the meal on the expression of mRNA of placental NIS in pregnant rat and breast NIS in lactating rats. Methods Wistar rats, weaning one month, were randomly divided into three groups according to the body weights, i.e., normal iodine (NI), ten fold high iodine(10HI), one hundred fold high iodine(100HI), the ratio of female and male was 2∶1. Iodine intake of the groups were about 6.15, 61.5 and 615.0 mg/d respectively. After 3 months of treatment, the urine iodine was determined by As-Ce-catalytic spectrophotometry. The rats mated and had offspring. Their placenta and breasts were taken on the seventeenth day of pregnancy and tenth day of lactation respectively. Then NIS mRNA expression was determined by RT-PCR. Results The urine iodine increased with the increase of the iodine intake. The urine iodine and iodine intake showed the parallel magnification. Compared with the NI group,AR value of the placental NIS mRNA in 100HI group and the breast NIS mRNA in 10HI and 100HI group significantly decreased. Conclusion Excessive iodine intake may down-regulate the expression of the placental and breast NIS, which presents a protective effect on offspring.

To explore the relationship between thyroid autoantibodies and thyroid function in school children aged 8-10 years,adults,pregnant women,and lactating women in China,in order to provide reference for the prevention and monitoring of thyroid disease.Healthy 8-10 years old school children (693 cases),adults (698 cases),pregnant women(325 cases),and lactating women(332 cases) from six iodine sufficient areas were enrolled.Serum TSH,FT4,and FT3 were determined by chemiluminescent immunoassay,while antithyroid antibody by radioimmunoassay.The positive rate of thyroid autoantibodies in females was significantly higher than that in the male (5.6％ vs 2.0％ in school children,and 22.8％ vs 3.2％ in adults) ; while positive rate of autoantibodies in pregnant and lactating women (8.9％,8.7％) were significantly lower than that in the other healthy adult women (22.8％).The incidence of abnormal thyroid function in antibody-positive people was higher than that in negative ones in all groups,and abnormal thyroid function showed mainly as subclinical hypothyroidism.In addition,lactating women with negative autoantibodies presented a higher incidence of abnormal thyroid function,mainly as low FT4.The abnormal thyroid function is related with the positive thyroid autoantibodies,indicating that it is essential to follow-up these people with positive antibodies in order to facilitate prevention,early diagnosis,and treatment of thyroid disease.Reference data for thyroid hormones in lactating women should be establisbed as soon as possible.

Thyroid function ultimately depends on appropriate iodine supply to the gland. Thyroid hormone deiodination is an intrinsic component of the thyroid hormone homeostasis. Type Ⅰ iodothyronine deiodinase (D1) plays an important role in thyroid hormone metabolism and has close relationship with thyroid function. Based on successfully establishing animal models of iodine deficiency and iodine excess in Babl/c mice (Babl/c mice were randomly divided into five groups: low iodine (LI), normal iodine (NI), five-fold iodine (5HI) , ten-fold iodine (10HI) and fifty-fold iodine (50HI) group. Three months and six months after admistration, they were sacrificed and thyroids were excised), the expression level of D1 mRNA were examined by using real time quantitative PCR method. D1 activity was analyzed by 125I-rT3 as substrate combined with ion-exchange chromatography. The thyroid hormone was measured with radioimmunoassay method. The data revealed that in the case of iodine deficiency, both D1 mRNA expression and D1 activity was greatly increased(compared with NI groups, P

Objective To set up the reference range for thyroid hormones and thyrotropin (TSH) of 8-10 years old school children in certain regions of China to provide reference criteria for diagnosis,treatment,and monitoring of thyroid diseases and related research.Methods A cross-sectional survey was conducted in primary school children aged 8-10 years from six iodine sufficient areas.664 normal school children were selected for establishing reference ranges of thyroid hormones and TSH after crucial screening through questionnaire and laboratory investigation.The serum hormone levels were determined by using chemiluminescent immunoassay (Bayer's reagents),and the reference range of each hormone was displayed as its 95％ central interval.Results The reference ranges of TSH,FT4,FT3,TT4,and TT3 were 1.03-8.42 mIU/L,13.44-20.59 pmol/L,4.75-6.96pmol/L,75.29-152.66 nmol/L,and 1.76-3.35 nmol/L,respectively.There was no significant difference in hormone levels between boys and girls.The eight years old group had slightly higher TT4 level compared with the other age groups.The rural children had higher TSH and TT3 levels and lower FT4 level than the urban children.Conclusion The thyroid hormone and TSH levels are substantially different between school children and adults.Therefore,it is necessary to establish the reference range of thyroid function indices for normal school children in order to diagnose,treat,and monitor thyroid diseases.

Objective To compare proprotein convertase subtilisin/kexin type 9 (PCSK9) levels between premenopausal and postmenopausal women,and to investigate the relationship between serum PCSK9 and metabolic factors.Methods Totally 515 women were enrolled from the study on diabetes of prediction,prevention,and intervention in Nanjing in 2009.Survey,physical examinations,and determination of related metabolic indexes were performed.Serum PCSK9 level was measured by sandwich ELISA.Results Serum PCSK9 level was positively correlated with low density lipoprotein-cholesterol (LDL-C),total cholesterol (TC),triglyceride,fasting plasma glucose,body mass index,waist-hip ratio,and age in women (all P＜0.01).PCSK9 level was significantly lower in premenopausal women than that in postmenopausal women [(58.18 ± 25.44 vs 80.91 ± 33.74) ng/ml,P ＜0.01].Conclusion Higher level of PCSK9 exists in postmenopausal women compared with premenopausal women.The level of PCSK9 is closely correlated with age,TC,and LDL-C.

Objective To add an open reading frame in the shuttle vector of pGFP ∷ CM for transfection of exogenous genes into Chlamydia muridarum.Methods The sequence of plasmid pGFP ∷ CM and new open reading frame (including promoter of pgp4,mCherry gene of red fluorescence protein and transcription termination sequence of Chlamydia trachomatis CT579) were amplified by polymerase chain reaction (PCR),and the products were transfected into Stellar competent cells.The recombinant plasmids were identified by PCR,enzyme digestion and sequencing.Then the recombinant plasmid was transfected into plasmid-free strain CMUT3,and the GFP-and mCherry-positive inclusions were observed under the fluorescence microscope.After the ampicillin selection and plaque purification,the purified CMUT3-pGFP-mCherry-CM was identified by indirect immunofluorecesent stain using anti-pgp3 and anti-glgA antibodies.Results The correct recombinant plasmid after sequencing identification,enzyme digestion and PCR amplification was successfully transfected into CMUT3,and the GFP-and mCherry-positive inclusions were observed.The transfected strain CMUT3-pGFP-mCherry-CM was purified after ampicillin selection and plaque purification.The expression of pgp3 and glgA protein in CMUT3-pGFP-mCherry-CM was similar to that in CMUT3-pGFP ∷ CM.Conclusion An open reading frame is successfully added in the plasmid pGFP ∷ CM,and the new plasmid can be transfected into CMUT3 and express exogenous protein,which can be used for further study on the function of single chlamydial protein.

Objective To observe the effects of different iodine intake on the thyroid tumor growth and thyroid function in the orthotopic nude mice model of human papillary thyroid carcinoma (PTC) cell line TPC-1.Methods Human PTC cell line TPC-1 (2 × 105) was injected into the left thyroid gland of nude mice.After the operation,the nude mice were randomly divided into three groups:low iodine group (LI),normal iodine group (NI),and high iodine group(HI,50 folds of normal iodine) based on the iodine levels contained in their diet.4 and 12 weeks later,the nude mice were executed,then their thyroid tumors were removed and weighted.The levels of urinary iodine were measured with As3+-Ce4+ catalytic spectrophotometry using ammonium persulfate digestion method.The thyroid hormone level was detected using chemiluminescent immunoassay.The morphology and structure of thyroid tumor tissue was observed by microscope.Results The iodine intervention feeding was successful according to urinary iodine level of LI,NI,and HI groups,paralleled to their iodine intakes.However,the difference of the weight of thyroid tumor in three groups had no statistical significance(P＞0.05).At 4 weeks,compared with control group,the levels of thyroid hormones were normal in NI group,while lower T4 and normal T3 were found in LI group.However,T4 was higher and T3 was lower in HI group (P＜0.05).At 12 weeks,the levels of thyroid hormones all were decreased due to the enlargement of thyroid gland tumor in NI,LI and HI groups.T4 and T3 in LI group were the lowest among three groups,even T4 was below detection limit.T4 was normal and T3 was lower in HI group as compared to control group.Conclusion Iodine intake may not significantly affect tumor growth in the orthotopic nude mice model of human PTC cell line TPC-1,but it has a significant effect on the synthesis of thyroid hormones.