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1.
Iodine deficiency disorder (IDD) has been recognized as a major public health problem worldwide and has serious detrimental effects on the growth and development of the children. Therefore, monitoring the iodine status of the school-aged children is of great importance. We randomly recruited 159 boarding school students (aged from 6 to 14) from 10 primary schools in Lincang County, Yunnan Province. The dietary iodine level of the students was measured by the new mixed meal method and chemical analysis. Fifty-seven daily water samples and 32 salt samples were collected from the same surveyed area to determine the iodine content using the sulfate cerium catalytic spectrophotometric method and the hyposulphite quantitative titration method, respectively. The iodine level of each water sample was ranged from 0.611 to 1.473 μg/L. The median and the mean value of the iodine content in water were 0.972 and 0.979?±?0.189 μg/L. The average iodine intake of each age group was higher that the recommended nutrient intakes (RNI) but lower than the tolerable upper intake level (UL). The median and the mean value of the iodine content in salt were 25.53 and 25.62?±?1.70 mg/kg. Taken together, the present study investigated the iodine intake status of Wa school-aged children through examination of their dietary iodine intake, the environment, and the salt iodine status. Results showed that the status of the iodine uptake of the Wa children were higher than the RNI, but lower than the UL.  相似文献   

2.
Thyroglobulin of very low iodine content has been prepared from a single non-toxic human goitre. The initial iodine content of the protein (0.038%) has been increased to levels of 0.16% and 0.85% by in vitro treatment with thyroid peroxidase and the resulting proteins studied with respect to their intrinsic fluorescence, circular dichroism spectra and binding of the hydrophobic probe 1,8-anilinonaphthalene sulfonic acid (ANS). While significant differences were observed between levels of iodination in both the ANS binding and intrinsic fluorescence of the thyroglobulin, no significant differences in the near and far UV circular dichroism spectra of the protein as a function of iodine content were observed. These data suggest that, the iodination of thyroglobulin effects specific areas of the protein without significant disruption of its overall secondary structure.  相似文献   

3.
Iodide is actively concentrated in the thyroid gland for thyroid hormone biosynthesis. Excess iodine has been observed to induce apoptosis in thyrocytes and mammary cells. The mechanism of iodine induced apoptosis is poorly understood. Among various cell organelles, mitochondria is known to provide conducive environment for the organification of iodine, i.e. iodination of different proteins. Mitochondria also play a central role in execution of apoptosis. To study the role of mitochondria in iodine induced apoptosis, we investigated the direct interaction of iodine and human breast mitochondria vis-a-vis its role in the initiation of apoptosis in vitro. We observed that mitochondria isolated from the tumor (TT) and extra-tumoral tissue (ET) of human breast display significant uptake of iodine. Mitochondrial proteins were observed to be predominantly iodinated in ET but not in TT mitochondria. Treatment with iodine showed an increase in mitochondrial permeability transition of TT and decrease in ET. Iodine induced released factor(s) other than cytochrome c from tumor mitochondria initiate(s) apoptosis in vitro, while those from ET mitochondria were non-apoptogenic in nature. To our knowledge, this is first report demonstrating that iodine acts differentially on mitochondria of tumor and extratumoral origin to release apoptogenic proteins from TT and has a protective effect on ET.  相似文献   

4.
The high fungistatic activity of tetraiodoethylene has been investigated. Diiodo-acetylene, which like tetraiodoethylene is an unsaturated substance containing only carbon and iodine, has also been found to have a high antifungal action. The effect of replacing the iodine atoms in these compounds by hydrogen, bromine, and carboxyl and nitro groups has been studied. The high fungistatic activity of some iodoethylenic and iodoacetylenic compounds appears to be associated with the presence in the molecule of positive iodine.  相似文献   

5.
Physicochemical investigation of the biologically active supplement Marinid has been carried out. Biological accessibility of iodine containing in Marinid has been determined. About 60 micrograms of iodine can be assimilated by thyroid from one 0.5 g Marinid tablet. Daily iodine need for groups of different age can be satisfied by 1-4 tablets. Marinid reduces 90Sr resorption from gastrointestinal tract by 20-40%.  相似文献   

6.
Previously reported models for radioiodine in ruminants cannot account for the effect of variations in stable iodine intake including large countermeasure doses of stable iodine on the transfer of radioiodine to goat milk. A metabolically based model of radioiodine transfer in goats has been parameterised using new experimental data on the effect of countermeasure doses of stable iodine on radioiodine transfer to milk. To account for the effect of dietary stable iodine levels, the model represents the transfer of iodine from the extracellular fluid to milk with Michaelis-Menten kinetics. The model shows good agreement with the experimental data, and the estimated parameters compare favourably with values which can be estimated from the literature. The parameterised model accounts for 95% of the variation in the observed data for milk, faeces, urine and thyroid (n=199). The model has been used to predict the effects of variation in stable iodine intake and the extent of consequent chemical contamination of milk by stable iodine. The time taken for radio-iodine to reach peak concentrations in milk following a deposition event is predicted to vary significantly (ca. 2 days) over a range of expected stable iodine intakes. Doses of stable iodine sufficient to reduce the radioiodine transfer to milk will result in stable iodine concentrations in milk greatly in excess of internationally advised limits. Therefore, we recommend that stable iodine supplementation not be used as a countermeasure to reduce radioiodine transfer to milk. Indeed, model predictions suggest that reductions in stable iodine intake would be a more effective countermeasure. However, this is unlikely to be feasible since the short physical half-life of 131I may not allow adequate time to implement changes in feed manufacture. The model described in this paper is freely available in ModelMaker 3.0 format (http://www.notingham.ac.uk/environmental-modelling/). Received: 16 August 1999 / Accepted in revised form: 15 November 1999  相似文献   

7.
An adequate intake of iodine in the diet of pregnant women is important to ensure normal growth and development of the fetus. It is difficult, however, to accurately determine iodine intakes using traditional methods of dietary assessment, primarily because the contribution of iodised salt use, at the table and in cooking, to total iodine intake is difficult to quantify. Given the limitations of dietary assessment, biochemical indices in blood and urine are typically used to assess iodine status in children and adults. Although reference ranges exist for thyroid hormones, there has been no consensus on the cut-offs needed in pregnancy to diagnose iodine deficiency. In contrast, a median urinary iodine concentration (UIC) of 150-249 μg/L has been established to determine the adequate iodine status of a group of pregnant women. However, the large intra-individual variation in UIC from either spot or 24h urine samples means that UIC cannot be used to assess iodine status in an individual pregnant woman. The difficulty in determining if an individual pregnant woman is iodine deficient is problematic for cross-sectional studies examining associations between iodine status in pregnancy and developmental outcomes in the child.  相似文献   

8.
Fifty patients with uncomplicated Graves' disease were treated with radioactive iodine (I(131)). Twenty-six patients who were followed for one year or longer are the basis of this report. Twenty-five are now euthyroid; only one is not completely well. The total dose of radioiodine administered varied from 0.5 to 10 millicuries. The average length of time necessary for return to a euthyroid state was from three to four months. Hypometabolism developed in three patients, and in one the signs and symptoms of myxedema developed. No other complications ensued. One patient who apparently relapsed had complete return to normal after further iodine administration. The determination of the uptake of radioactive iodine by the thyroid gland is a useful diagnostic procedure in differentiating conditions simulating hyperthyroidism.Following treatment with radioactive iodine, the thyroid gland becomes smaller, the uptake of iodine by the gland is reduced, and the level of organic iodine in the plasma becomes normal. In acute thyroiditis, in spite of a high basal metabolic rate, high content of organic iodine in the plasma and other evidences of "hyperthyroidism," the uptake of I(131) has been very low.  相似文献   

9.
An assessment of effectiveness of the administering of single dose of stable iodine in Poland on the reduction of 131I doses in thyroid has been performed. 5-compartment model of metabolism of iodine developed by Johnson has been used to evaluate predicted levels of stable iodine and 131I content in thyroid and commitment dose equivalent H50 for different doses of stable iodine and various age and sex group population. The measured values of 131I concentration in air and in milk and standard values for milk and food consumption and inhalation rate as well as metabolic parameters were used. Theoretical calculations showed that administering of stable iodine on 1986-04-28, 1986-04-29, 1986-04-30 and 1986-05-01 could have reduced committed dose equivalent H50 form ingestion with inhalation pathway by about 44%, 40%, 26%, 12% respectively. On the basis of measured 131I activity in the thyroid for inhabitants from different districts in Poland (1400 measurement) committed dose equivalents were determined and analysis of radiation hazard from 131I were performed. In the most contaminated regions of Poland average H50 doses for children 1-5 and 5-10 years old are close to 50 mSv (permissible level for population) and maximal doses exceed this limit four times. These maximal doses occurred for about from 5% inhabitants from these area. In the moderate and low contaminated regions of Poland the average doses are fivefold and tenfold less respectively.  相似文献   

10.
动物实验表明,短期或长期高碘摄入会对机体产生一定的毒性,包括发育毒性、遗传毒性和致畸性等。目前世界各国家及组织对于碘的推荐摄入量(reference nutrition intake,RNI)和可耐受最高摄入量(tolerable upper intake level,UL)的制定一般是基于一些的人体实验研究和人群调查,但由于地理环境及人种差异等原因,所得数据并不统一。由于参照的研究数据不同,各国对不同人群设定的碘安全摄入量参照标准也不尽相同。鉴于此,分析了国际上主要的国家及国际组织制订标准的过程与依据,概述了我国相关标准的制订过程与依据以及El前的研究进展,明确了进一步探讨和研究更适合我国人群的碘的安全摄入量是当前和今后的工作重点之一,也是食盐加碘计划(universal salt iodization,USI)科学实施的重要保障。  相似文献   

11.
Production technology of iodinized spirulina biomass at vertical panel airlifted photobioreactor has been developed. The influence of different concentrations of iodine ions at certain combinations with cobalt ions on iodine-accumulative properties of spirulina has been studied. It has been shown that it is possible to obtain spirulina biomass containing certain amount of organically bound iodine by varying cobalt and iodine ions combinations and by staged addition of ions to incubation medium. This technique of staged addition of iodine and cobalt salt allowed to adopt spirulina to their high amount in the incubation medium, to increase spirulina productivity during growth, and to produce biomass with large iodine content.  相似文献   

12.
Cultures of the causal fungus of Kikuyu Yellows disease of Pennisetum clandestinum isolated from Australia have been examined. The fungus is described. The oospore has three noteworthy features: it is plerotic even into the oogonial neck; the ooplast appears to develop a condensed core; the relative thicknesses of the oospore wall layers appear to differ from those of other Oomycetes. Oogonial characters and parasitism indicate an affinity with the graminicolous downy mildews. However, asexual sporulation is not immediately reconcilable with that of these mildews. A major re-appraisal of the classification of the peronosporalean fungi has been necessary to accommodate this fungus. Attention has been drawn to mycelial morphology. Three new orders and two new families are recognized. The division between the peronosporalean fungi and saprolegnialean fungi is recognized at the sub-class level.  相似文献   

13.
The Polish Council for Control of Iodine Deficiency Disorders (PCCIDD) was established in 1991 in Krakow at the Chair and Dept. of Endocrinology, Jagiellonian University, Collegium Medicum, following the example of the International Council for Control of Iodine Deficiency Disorders (ICCIDD) in Charlottesville, USA. The PCCIDD co-operates with the European Co-ordinating Centre in Pisa, Italy. The PCCIDD comprises a group of experts in endocrinology, iodine prophylaxis, the technology of salt and food iodisation, and Polish representatives of several organisations: WHO, UNICEF, the Polish Consumers Federation, and the Spokesman for Children's Rights. The strategic goal of the Polish Council is to solve the problem of iodine deficiency in Poland realising the Programme for Elimination of Iodine Deficiency financed by the Ministry of Health. The Polish model of iodine prophylaxis contains obligatory iodisation of household salt (20-40 mg KI/1 kg) and neonates' formula (10 μg/100 mL of milk), and additional supplementation for pregnant and breastfeeding women with 150-200 μg of iodine as pharmacotherapy. The model is very effective: endemic goitre in schoolchildren has been eradicated, the prevalence of goitre in pregnant women has fallen from 80% to 19%, the frequency of transient hypothyroidism in neonates has dropped from 2.0% to 0.16%, and the observed increase of incidence rate of thyroid cancer in women over 40 years old has diminished markedly. In 2008, a WHO Collaborating Centre (WHOCC) for Nutrition was designated at the Department of Endocrinology, UJCM in Krakow. The main goal of the WHOCC is to sustain effective iodine prophylaxis in Poland in the light of the latest WHO recommendations on the necessary reduction of daily salt intake as a risk factor for hypertension and arteriosclerosis. Therefore, additional standardised carriers of iodine (milk, mineral water) have been introduced into the food market.  相似文献   

14.
Electron Energy Loss Spectroscopy (EELS) has been used to study the lysosomal distribution of iodine atoms in mouse thyroid cells. High resolution and high magnification pictures show that iodine atoms are located on protein network with regular polyedric meshes.  相似文献   

15.
In severe iodine deficient areas, iodine deficiency has been documented to be an important etiological factor leading to poor fetal growth and development. Iodine is essential for physical growth and development of the central nervous system of the fetus. Iodine deficiency in pregnant mothers leads to increased incidence of infertility and abortions, perinatal mortality and infant child mortality. The clinical iodine supplementation trials have documented adverse health consequences due to iodine deficiency. Evidence from observational studies concludes that prevention of iodine deficiency can lead to reduction in infant mortality rate and facilitate to achieve millennium development goal-4.  相似文献   

16.
Spores from five genera of filamentous fungi were measured by light microscopy using thirteen different mounting and staining techniques. The measurements obtained for the different methods for each organism were compared. Measurements taken in mountants and stains such as 40% KOH, Lugol's iodine, and cold lactophenol cotton blue showed significant differences with four of the five isolates. Comparisons between living and herbarium specimens suggested that for other mountants this would not give rise to significant differences. Possible explanations for these results are reviewed, their significance for critical taxonomic studies considered, and recommendations to mycologists are made.  相似文献   

17.
Studies on the tropical marine fungi of Brunei   总被引:4,自引:0,他引:4  
Driftwood, mangrove roots and branches, and seaweeds were examined for marine fungi from beaches, rocky shorelines, an artificial lake and mangrove stands. Ninety-five species, some new to science were recorded. This is the largest number of marine fungi reported from a single study. Our knowledge of the geographic distributions of these fungi has been extended. New and rare species are illustrated at the light microscope and SEM levels.  相似文献   

18.
Epidemiological investigations have shown that at the Bia?ystok Province about 30% of children and youth is afflicted with goitre. In this area drinking water is poor in iodine and iodine supply with food is quite unsatisfactory. The purpose of the present work has been to check the behaviour of the serum and urine iodine in children with thyroid goitre. The estimations of I in blood serum were made in 126 children with goitre (I, II, and III, according to the WHO classification) and in 100 healthy children. The method used included buthanol extraction according to Fisher and Morris. The concentration of iodine and its excretion rate in urine were assessed in 119 children with goitre of various advancement, an; in 170 children not affected with goitre, using the method of Fisher and Morris adopted to urine analysis. The authors found the following values for serum protein bound iodine: control group 4.9 microgram/100 ml, at average; 4.3 microgram/100 ml, 3.0 microgram/100 ml, and 2.6 microgram/100 ml in those affected with I, II, and III of the goitre, respectively. The 24 hr urine excretion rate of iodine in healthy children amounted to 66.4 microgram, and 64.2 microgram, 53.6 microgram, and 4o.2 microgram in those with I, II, and III goitre, respectively. The above results indicate a significant decrease of iodine concentration in blood serum and in urine in children with goitre; this decrease has been found to be dependent on the degree of the thyroid gland enlargement. The differences were statistically significant.  相似文献   

19.
Chemical quenching, gel filtration or liquid phase extraction procedures are currently in vogue for taking iodine off from the reaction mixtures in which it is used to cause the formation of disulfide bonds in acetamidomethyl or trityl protected peptides. It has been found that charcoal effectively, selectively and rapidly removes iodine by solid phase extraction from reaction mixtures in which it is used to convert the acetamidomethyl protected precursors of oxytocin or a peptide from the Pre-S1 region of hepatitis B virus into their intramolecularly disulfide-bonded products. The advantages of this new method, namely simplicity, rapidity, quantitative yields, freedom from side reactions, linear scalability, cost effectiveness and adsorption of iodine on to solid charcoal are discussed.  相似文献   

20.
Iodine-enhanced vegetable has been proven to be an effective way to reduce iodine deficiency disorders in many regions. However, the knowledge about what mechanisms control plant uptake of iodine and where iodine is stored in plants is still very limited. A series of controlled experiments, including solution culture, pot planting, and field experiments were carried out to investigate the uptake mechanism of iodine in different forms. A new methodology for observing the iodine distribution within the plant tissues, based on AgI precipitation reaction and transmission electron microscope techniques, has been developed and successfully applied to Chinese cabbage. Results show that iodine uptake by Chinese cabbage was more effective when iodine was in the form of IO3 than in the form of I if the concentration was low (<0.5 mg L−1), but the trend was opposite if iodine concentration was 0.5 mg L−1 or higher. The uptake was more sensitive to metabolism inhibitor in lower concentration of iodine, which implies that the uptake mechanism transits from active to passive as the iodine concentration increases, especially when the iodine is in the form of IO3 . The inorganic iodine fertilizer provided a quicker supply for plant uptake, but the higher level of iodine was toxic to plant growth. The organic iodine fertilizer (seaweed composite) provided a more sustainable iodine supply for plants. Most of the iodine uptake by the cabbage is intercepted and stored in the fibrins in the root while the iodine that is transported to the above-ground portion (shoots and leaves) is selectively stored in the chloroplasts.  相似文献   

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