Thirty-two Wistar rats were divided randomly into four groups of eight with six females and two males in each group. The rats were exposed to high fluoride drinking water （45 mg F-L^-1 from 100 mg NaF L-1）, low diet...Thirty-two Wistar rats were divided randomly into four groups of eight with six females and two males in each group. The rats were exposed to high fluoride drinking water （45 mg F-L^-1 from 100 mg NaF L-1）, low dietary iodine （0.0855 mg kg-1）, or both together in order to assess the effects of these three regimens on the thyroid function of the offspring rats. After the animal model was established, the offspring rats were bred and 10-, 20-, 30-, 60-, and 90-d-old rats were used for the experiment. The treatments for the offspring rats were the same as those of their parents. In comparison with control rats, the relative thyroid glands were changed by three regimens, but the mean values of thyroid weight in the experimental groups saw no marked difference. Serum TT3 levels were increased in all stages in the low iodine （LI） group. In the high fluoride （HiF） group, increase in TT3 levels was observed except in 20-d-old rats. Decrease in TT3 at 20- and 90-d and increase in TT3 at 30- and 60-d were found in HiF＋LI group. Serum TT4 levels first saw an increase, and then dropped in the LI and HiF＋LI group. However, an increase in TT4 was found in the HiF group. The levels of TSH in serum rocketed at d 20, and then dropped in the next stages in experimental groups. The results suggested that thyroid disorder could be induced by high flroride in drinking water, low iodine diet, or both of them. Exposure time to fluoride or low iodine diet was one of the important factors that fluoride can induce the development of thyroid dyfunction.展开更多
The present study determined the thyroid hormone interference of tetrabromobisphenol A （TBBPA） in Sprague-Dawley （SD） rats, and the derived-reference dose （RfD） of different endpoint effects on mammals based on ...The present study determined the thyroid hormone interference of tetrabromobisphenol A （TBBPA） in Sprague-Dawley （SD） rats, and the derived-reference dose （RfD） of different endpoint effects on mammals based on experimental results and data collection. Based on repeated exposure toxicity tests on mammals and extensive research, the present study used BMDS240 Software to derive a benchmark dose, and analyzed the accuracy and uncertainty, and similarity with other studies. Test results on triiodothyronine （T3）, thyroxine （T4）, and thyroid stimulating hormone （TSH） demonstrated that all the indicators presented a non-monotonous dose-effect relationship clearly, except TSH in male rats exposed to 0-1000 mg/kg BW per day. Therefore, RfDs were derived from different critical effects. In summary, RfD for mammals in the present study was found to be 0.6 mg/kg per day.展开更多
BACKGROUND： Zinc （Zn） has been shown to greatly influence brain development. Zn supplements may reduce injury to cell membranes of the thyroid gland due to iodine deficiency. OBJECTIVE： To establish an iodine defi...BACKGROUND： Zinc （Zn） has been shown to greatly influence brain development. Zn supplements may reduce injury to cell membranes of the thyroid gland due to iodine deficiency. OBJECTIVE： To establish an iodine deficiency rat model using low-iodine food, which was supplemented with compound Zn and Zn gluconate, to observe the effects of Zn on brain development, as well as pituitary gland and thyroid gland function in iodine-deficient rats. DESIGN, TIME AND SETTING： Randomized grouping study of neural development was performed in the central laboratory of Shandong Institute for Prevention and Treatment of Endemic Disease from 1998 to 1999. MATERIALS： A total of 270 Wistar, female rats, one month after weaning, were used in this study, including 150 pregnant and 120 neonatal rats. Rats were randomly divided into six groups： normal control, model, iodine, compound Zn, iodine and compound Zn, and zinc gluconate. Each group contained 25 pregnant rats and 20 neonatal rats. METHODS： The pregnant rats and 20 neonatal rats, and well as the normal group, were fed standard chow and allowed free access to tap water （containing 5 u g/L iodine and 1 mg/L Zn）. The remaining five groups were fed low-iodine chow. However, the model group received distilled water, the iodine group received potassium-iodide distilled water （containing 300 u g/L iodine）, the compound Zn group received distilled water and intragastrically administrated 10 mL/kg compound Zn solution, once per day, the iodine and compound Zn group received distilled water with 300 u g/L iodine and intragastrically administrated 10 mL/kg compound Zn solution, once per day. All treatments lasted 90 days. MAIN OUTCOME MEASURES： All pregnant rats were sacrificed on the day 21 of pregnancy. Body mass number and rate of fetal absorption, as well as fetal death and malformation, were determined. Thyroid and pituitary gland weights were measured, as well as serum levels of thyroid hormone, gonadotropin, and sex hormones. In the experimental study of neonatal rats, the animals normally gave birth at day 21. At day 45 after birth of the neonatal rats, thyroid and pituitary gland weights were measured, and protein, DNA, and RNA concentrations were measured. RESULTS： Pregnant rats in the iodine group exhibited decreased urine iodine and body mass （F = 7.37, P 〈 0.01 ）, increased thyroid absolute and relative weight （F= 7.01, 50.27, P 〈 0.01）, as well as decreased T4 and FF4 （F = 7.01, 29.32, P 〈 0.01 ） and increased T3 and VI＇3 （F = 41.20, 5.94, P 〈 0.01）. Gonadotropic and sexual hormones were abnormal. The pregnant rats displayed decreased weight gain, and the rates of malformation, dead, and absorbed fetuses were increased. Compared with the control group, the neonatal rats with iodine deficiency exhibited lower brain weights （P 〈 0.01 ）. Brain protein, DNA, and RNA, concentrations were decreased, with a rate of RNA/DNA （F = 5.70, 55.86, 25.65, 5.44, P 〈 0.01）. Body mass was gradually increased （F= 6.74, P 〈 0.01）, and the thyroid glands were enlarged （F= 50.01, 76.13, P 〈 0.01）. Following Zn administration, thyroid gland weight was decreased in pregnant rats （P 〈 0.01 ）. Thyroid hormone, gonadotropic hormones, and sexual hormones were restored to some degree. Fetal weight was increased, and the rates of malformation, dead, and absorbed fetuses were decreased. At the same time, neonatal rats gained body weight, displayed decreased thyroid gland weight, as well as increased protein, DNA, and RNA concentrations in the brain. The ratio of RNA/DNA and protein/DNA increased following Zn administration （P 〈 0.01 ）. CONCLUSION： Zn supplementation may decrease the degree of goiter, ameliorate thyroid hormone disorder, as well as gonadotropic and sexual hormone disorders, and increase protein, DNA, and RNA content. Zn supplementation antagonized reproductive abnormalities in pregnant rats, decreased fetal growth,and disturbed brain development in neonatal rats as a result of iodine deficiency.展开更多
Four hundred and thirty-seven patients with papillary thyroid carcinoma were treated from April 1963 to December 1989. The main treatment was surgery which was divided into 4 types: lobectomy combined with neck dissec...Four hundred and thirty-seven patients with papillary thyroid carcinoma were treated from April 1963 to December 1989. The main treatment was surgery which was divided into 4 types: lobectomy combined with neck dissection (RND or MND); total thyroidectomy; isthmusectomy plus lobectomy; lobectomy combined with RND and then followed by contralateral MND. The 10-year survival rates of these four groups were 88.6%, 89.5% to % and 80%, respectively. The overall 5, 10 and 15-year survival rates were 92.7%, 87.9%,79.4%. Lymph node metastasis was present in 80%. The authors believe that functional neck dissection is indicated if the number of lymph node is limited and the size is small.展开更多
In the present study, we investigated the effects of hypothyroidism on the morphology of astrocytes and microglia in the hippocampus of Zucker diabetic fatty rats and Zucker lean control rats. To induce hypothyroidism...In the present study, we investigated the effects of hypothyroidism on the morphology of astrocytes and microglia in the hippocampus of Zucker diabetic fatty rats and Zucker lean control rats. To induce hypothyroidism, Zucker lean control and Zucker diabetic fatty rats at 7 weeks of age orally received the vehicle or methimazole, an anti-thyroid drug, treatment for 5 weeks and were sacrificed at 12 weeks of age in all groups for blood chemistry and immunohistochemical staining. In the me- thimazole-treated Zucker lean control and Zucker diabetic fatty rats, the serum circulating triiodo- thyronine （T3） and thyroxine （＇I＂4） levels were significantly decreased compared to levels observed in the vehicle-treated Zucker lean control or Zucker diabetic fatty rats. This reduction was more prominent in the methimazole-treated Zucker diabetic fatty group. Glial fibrillary acidic protein im- munoreactive astrocytes and ionized calcium-binding adapter molecule 1 （Iba-1）-immunoreactive microglia in the Zucker lean control and Zucker diabetic fatty group were diffusely detected in the hippocampal CA1 region and dentate gyrus. There were no significant differences in the glial fibril- lary acidic protein and Iba-1 immunoreactivity in the CA1 region and dentate gyrus between Zucker lean control and Zucker diabetic fatty groups. However, in the methimazole-treated Zucker lean control and Zucker diabetic fatty groups, the processes of glial fibrillary acidic protein immunoreac- tive astrocytes and Iba-1 immunoreactive microglia, were significantly decreased in both the CA1 region and dentate gyrus compared to that in the vehicle-treated Zucker lean control and Zucker diabetic fatty groups. These results suggest that diabetes has no effect on the morphology of as- trocytes and microglia and that hypothyroidism during the onset of diabetes prominently reduces the processes of astrocytes and microglia.展开更多
基金sponsored by the National Natural Science Foundation of China (30170681)the Foundation of Henan Institute of Science and Technology, China(6007)
文摘Thirty-two Wistar rats were divided randomly into four groups of eight with six females and two males in each group. The rats were exposed to high fluoride drinking water （45 mg F-L^-1 from 100 mg NaF L-1）, low dietary iodine （0.0855 mg kg-1）, or both together in order to assess the effects of these three regimens on the thyroid function of the offspring rats. After the animal model was established, the offspring rats were bred and 10-, 20-, 30-, 60-, and 90-d-old rats were used for the experiment. The treatments for the offspring rats were the same as those of their parents. In comparison with control rats, the relative thyroid glands were changed by three regimens, but the mean values of thyroid weight in the experimental groups saw no marked difference. Serum TT3 levels were increased in all stages in the low iodine （LI） group. In the high fluoride （HiF） group, increase in TT3 levels was observed except in 20-d-old rats. Decrease in TT3 at 20- and 90-d and increase in TT3 at 30- and 60-d were found in HiF＋LI group. Serum TT4 levels first saw an increase, and then dropped in the LI and HiF＋LI group. However, an increase in TT4 was found in the HiF group. The levels of TSH in serum rocketed at d 20, and then dropped in the next stages in experimental groups. The results suggested that thyroid disorder could be induced by high flroride in drinking water, low iodine diet, or both of them. Exposure time to fluoride or low iodine diet was one of the important factors that fluoride can induce the development of thyroid dyfunction.
基金supported by the National Natural Science Foundation of China(No.21377045)Joint Innovation Funding of Production and Research-a Prospective Joint Research Project(BY2015027-05)
文摘The present study determined the thyroid hormone interference of tetrabromobisphenol A （TBBPA） in Sprague-Dawley （SD） rats, and the derived-reference dose （RfD） of different endpoint effects on mammals based on experimental results and data collection. Based on repeated exposure toxicity tests on mammals and extensive research, the present study used BMDS240 Software to derive a benchmark dose, and analyzed the accuracy and uncertainty, and similarity with other studies. Test results on triiodothyronine （T3）, thyroxine （T4）, and thyroid stimulating hormone （TSH） demonstrated that all the indicators presented a non-monotonous dose-effect relationship clearly, except TSH in male rats exposed to 0-1000 mg/kg BW per day. Therefore, RfDs were derived from different critical effects. In summary, RfD for mammals in the present study was found to be 0.6 mg/kg per day.
基金the Scientific and Technology Bureau of Shandong Province, No. 1996 BBIDKA1
文摘BACKGROUND： Zinc （Zn） has been shown to greatly influence brain development. Zn supplements may reduce injury to cell membranes of the thyroid gland due to iodine deficiency. OBJECTIVE： To establish an iodine deficiency rat model using low-iodine food, which was supplemented with compound Zn and Zn gluconate, to observe the effects of Zn on brain development, as well as pituitary gland and thyroid gland function in iodine-deficient rats. DESIGN, TIME AND SETTING： Randomized grouping study of neural development was performed in the central laboratory of Shandong Institute for Prevention and Treatment of Endemic Disease from 1998 to 1999. MATERIALS： A total of 270 Wistar, female rats, one month after weaning, were used in this study, including 150 pregnant and 120 neonatal rats. Rats were randomly divided into six groups： normal control, model, iodine, compound Zn, iodine and compound Zn, and zinc gluconate. Each group contained 25 pregnant rats and 20 neonatal rats. METHODS： The pregnant rats and 20 neonatal rats, and well as the normal group, were fed standard chow and allowed free access to tap water （containing 5 u g/L iodine and 1 mg/L Zn）. The remaining five groups were fed low-iodine chow. However, the model group received distilled water, the iodine group received potassium-iodide distilled water （containing 300 u g/L iodine）, the compound Zn group received distilled water and intragastrically administrated 10 mL/kg compound Zn solution, once per day, the iodine and compound Zn group received distilled water with 300 u g/L iodine and intragastrically administrated 10 mL/kg compound Zn solution, once per day. All treatments lasted 90 days. MAIN OUTCOME MEASURES： All pregnant rats were sacrificed on the day 21 of pregnancy. Body mass number and rate of fetal absorption, as well as fetal death and malformation, were determined. Thyroid and pituitary gland weights were measured, as well as serum levels of thyroid hormone, gonadotropin, and sex hormones. In the experimental study of neonatal rats, the animals normally gave birth at day 21. At day 45 after birth of the neonatal rats, thyroid and pituitary gland weights were measured, and protein, DNA, and RNA concentrations were measured. RESULTS： Pregnant rats in the iodine group exhibited decreased urine iodine and body mass （F = 7.37, P 〈 0.01 ）, increased thyroid absolute and relative weight （F= 7.01, 50.27, P 〈 0.01）, as well as decreased T4 and FF4 （F = 7.01, 29.32, P 〈 0.01 ） and increased T3 and VI＇3 （F = 41.20, 5.94, P 〈 0.01）. Gonadotropic and sexual hormones were abnormal. The pregnant rats displayed decreased weight gain, and the rates of malformation, dead, and absorbed fetuses were increased. Compared with the control group, the neonatal rats with iodine deficiency exhibited lower brain weights （P 〈 0.01 ）. Brain protein, DNA, and RNA, concentrations were decreased, with a rate of RNA/DNA （F = 5.70, 55.86, 25.65, 5.44, P 〈 0.01）. Body mass was gradually increased （F= 6.74, P 〈 0.01）, and the thyroid glands were enlarged （F= 50.01, 76.13, P 〈 0.01）. Following Zn administration, thyroid gland weight was decreased in pregnant rats （P 〈 0.01 ）. Thyroid hormone, gonadotropic hormones, and sexual hormones were restored to some degree. Fetal weight was increased, and the rates of malformation, dead, and absorbed fetuses were decreased. At the same time, neonatal rats gained body weight, displayed decreased thyroid gland weight, as well as increased protein, DNA, and RNA concentrations in the brain. The ratio of RNA/DNA and protein/DNA increased following Zn administration （P 〈 0.01 ）. CONCLUSION： Zn supplementation may decrease the degree of goiter, ameliorate thyroid hormone disorder, as well as gonadotropic and sexual hormone disorders, and increase protein, DNA, and RNA content. Zn supplementation antagonized reproductive abnormalities in pregnant rats, decreased fetal growth,and disturbed brain development in neonatal rats as a result of iodine deficiency.
文摘Four hundred and thirty-seven patients with papillary thyroid carcinoma were treated from April 1963 to December 1989. The main treatment was surgery which was divided into 4 types: lobectomy combined with neck dissection (RND or MND); total thyroidectomy; isthmusectomy plus lobectomy; lobectomy combined with RND and then followed by contralateral MND. The 10-year survival rates of these four groups were 88.6%, 89.5% to % and 80%, respectively. The overall 5, 10 and 15-year survival rates were 92.7%, 87.9%,79.4%. Lymph node metastasis was present in 80%. The authors believe that functional neck dissection is indicated if the number of lymph node is limited and the size is small.
基金supported by the National Research Foundation of Korea Grant funded by the Korean Government(MEST),Republic of Korea,No.2010-0007712
文摘In the present study, we investigated the effects of hypothyroidism on the morphology of astrocytes and microglia in the hippocampus of Zucker diabetic fatty rats and Zucker lean control rats. To induce hypothyroidism, Zucker lean control and Zucker diabetic fatty rats at 7 weeks of age orally received the vehicle or methimazole, an anti-thyroid drug, treatment for 5 weeks and were sacrificed at 12 weeks of age in all groups for blood chemistry and immunohistochemical staining. In the me- thimazole-treated Zucker lean control and Zucker diabetic fatty rats, the serum circulating triiodo- thyronine （T3） and thyroxine （＇I＂4） levels were significantly decreased compared to levels observed in the vehicle-treated Zucker lean control or Zucker diabetic fatty rats. This reduction was more prominent in the methimazole-treated Zucker diabetic fatty group. Glial fibrillary acidic protein im- munoreactive astrocytes and ionized calcium-binding adapter molecule 1 （Iba-1）-immunoreactive microglia in the Zucker lean control and Zucker diabetic fatty group were diffusely detected in the hippocampal CA1 region and dentate gyrus. There were no significant differences in the glial fibril- lary acidic protein and Iba-1 immunoreactivity in the CA1 region and dentate gyrus between Zucker lean control and Zucker diabetic fatty groups. However, in the methimazole-treated Zucker lean control and Zucker diabetic fatty groups, the processes of glial fibrillary acidic protein immunoreac- tive astrocytes and Iba-1 immunoreactive microglia, were significantly decreased in both the CA1 region and dentate gyrus compared to that in the vehicle-treated Zucker lean control and Zucker diabetic fatty groups. These results suggest that diabetes has no effect on the morphology of as- trocytes and microglia and that hypothyroidism during the onset of diabetes prominently reduces the processes of astrocytes and microglia.
