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Sample records for plasma thyroxine t4

  1. Quantitation of T-3 (triiodothyronine) and T-4 (thyroxine) in serum and plasma. Draft report

    International Nuclear Information System (INIS)

    Ceglowski, W.; Williams, R.B.

    1981-12-01

    This report summarizes an examination of the published literature concerning the quantitation of thyroxine and triiodothyronine in the clinical laboratory. It therefore details the precision, accuracy, sensitivity, and specificity obtainable in various commercial systems and those devised in the clinical laboratory. The data produced by several of the procedures often indicate that improvements in these parameters would enhance overall assay performance and increase the reliability of the clinical interpretation derivable from assay results. For T-3 and T-4 in vitro assays a very large number of systems exist and are currently being utilized in clinical laboratories in this country. For the sake of brevity some systems, while mentioned, are not reviewed in exhaustive detail. Radioimmunoassay, as the most frequently performed assay for both T-3 and T-4 is extensively reviewed. Also discussed with particular interest are assay systems which will undoubtedly impact on the future course of thyroid hormone assessment in the clinical laboratory, namely enzyme immunoassay and fluorescent immunoassay. The state of the art in T-4 measurements in neonates, because it is such a critical area for application of in vitro thyroid testing, is given detailed review. The quantitation of free thyroxine has been discussed in detail. These assays have been gaining more frequent use in the clinical laboratory and increased commercial system development

  2. Determination of serum free thyroxine concentration (FT4) by means of fT4-fraction and total thyroxine concentration

    International Nuclear Information System (INIS)

    Passath, A.; Leb, G.

    1985-01-01

    A new equilibrium assay for the determination of serum free thyroxine was evaluated in 514 patients. The assay comprises a two-vial-procedure to measure total thyroxine and free thyroxine fraction by use of monoclonal antibodies. Free thyroxine concentrations are calculated from fT 4 -fraction and total thyroxine concentration readings. In euthyroidism the average free thyroxine fraction (%fT 4 ) was 0.011%, in hyperthyroidism this fraction was elevated, in hypothyroidism it was below normal. In patients with TBG anomalies, TBG values were inversely correlated with fT 4 fraction readings. The 'euthyroid reference range' of FT 4 (SPAC ET) was between 0.70 to 1.78ng/dl. This euthyroid range of FT 4 was determined from TT 4 concentrations measured by T 4 -RIA (SPAC T 4 MONO) which were 30% above TT 4 values measured by conventional T 4 -RIA (SPAC T 4 POLY; polyclonal antibodies). However, a different euthyroid range of FT 4 between 0.55 to 1.30 ng/dl was observed as well as by other investigators when conventional T 4 -RIA measurements were used for calculation of FT 4 values. Our results indicate that calculated FT 4 concentration values are highly dependent on the methods used for determination of total thyroxine concentrations. Precision and reproducability of this two vial equilibrium assay did not meet the requirements mandatory for the application as a clinical routine diagnostic procedure, and its general use for this purpose can as yet not be recommended. (Author)

  3. Sensitive radioimmunoassay of total thyroxine (T4) in horses using a simple extraction method.

    Science.gov (United States)

    Tangyuenyong, Siriwan; Nambo, Yasuo; Nagaoka, Kentaro; Tanaka, Tomomi; Watanabe, Gen

    2017-07-28

    Most thyroid hormone determinations in animals are based on immunoassays adapted from those used to test human samples, which may not reflect the actual values of thyroid hormone in horses because of the presence of binding proteins. The aims of the present study were i) to establish a novel radioimmunoassay (RIA) using a more simple and convenient method to separate binding proteins for the measurement of total thyroxine (T4) in horses and ii) to validate the assay by comparing total T4 concentrations in yearling horses raised in different climates. Blood samples were collected from trained yearlings in Hokkaido (temperate climate) and Miyazaki (subtropical climate) in Japan and from adult horses in estrus and diestrus. T4 was extracted from both serum and plasma using modified acid ethanol cryo-precipitation and sodium acetate ethanol methods. Circulating total T4 concentrations were determined by RIA. T4 concentration by sodium acetate ethanol was appropriately detectable rather than sodium salicylate method and was the same as for acid ethanol method. Furthermore, this sodium acetate ethanol method required fewer extraction steps than the other methods. Circulating T4 concentrations in yearlings were 225.98 ± 20.89 ng/ml, which was higher than the previous reference values. With respect to climate, T4 levels in Hokkaido yearlings tended to be higher than those in Miyazaki yearlings throughout the study period. These results indicated that this RIA protocol using a modified sodium acetate ethanol separation technique might be an appropriate tool for specific measurement of total T4 in horses.

  4. Development and evaluation of a magnetic solid-phase radioimmunoassay for total human thyroxine (T4)

    International Nuclear Information System (INIS)

    Abbas, S. H.; Hassan, A. M. E.; Abdalla, O. M.; Zahran, A. B.; Shabbo, N. M.; Ali, N. I.; Gubara, A.

    2009-02-01

    In this study a simple and rapid magnetic solid-phase radioimmunoassay (RIA) for human thyroxine (T4) was developed using locally raised sheep thyroxine antibody and radioiodinated thyroxine (T4) tracer by chloramine-T method. The assay involves two hours incubation at ambient temperature rang (30 to 35 o C ) associated with the antibody covalently linked by the easily performed carbonyldiimidazole (CDI) method to magnetic particles obtained from SIPAC. 0.1% triton with sodium azide used as a wash buffer. L-Thyroxine Na-salt peta hydrate from sigma was used for the preparation of standards and quality control sera. The coupled magnetic anti-T4 solid phase titrated in order to find out the suitable antibody concentration (titre) to be used in the assay. Optimizations followed by validation procedures were done. When correlated with kits imported from NETRIA and AMERSHAM, results were found to be highly comparable r=0.965 and p<0.05. Shelf life was also studied, so that the local prepared T4 RIA magnetic reagents can be used for the measurement of total human thyroxine with a very low cost compared to imported kits. (Author)

  5. Concentrações plasmáticas de testosterona, triiodotironina (T3 e tiroxina (T4 em bodes submetidos ao estresse calórico Plasma concentrations of testosterone, triiodothyronine (T3, and thyroxine (T4 in bucks submitted to heat stress

    Directory of Open Access Journals (Sweden)

    L.A. Coelho

    2008-12-01

    Full Text Available Para verificar o efeito do estresse calórico (EC nas concentrações plasmáticas de testosterona, triiodotironina (T3 e tiroxina (T4, oito bodes, das raças Saanen (n=4 e Alpina (n=4, foram mantidos em câmara bioclimática, sob condições de termoneutralidade (13,0ºC a 26,7ºC durante 30 dias e, após um período (60 dias de descanso, submetidos ao EC (23,7ºC a 34,0ºC por 30 dias. Para minimizar as variações sazonais nos perfis hormonais devido ao fotoperíodo, durante toda fase experimental, incluindo a de adaptação em condições de termoneutralidade (30 dias, o fotoperíodo foi controlado utilizando-se alternância de dias longos (16h de luz e 8h de escuro e de dias curtos (8h de luz e 16h de escuro a cada 30 dias. As amostras de sangue foram coletadas duas vezes por semana durante cinco semanas. No conjunto das raças, o EC não influenciou (P>0,05 as concentrações de testosterona (1,8±0,2 vs 1,3±0,2ng/ml e nem a de T4 (52,7±2,8 vs 50,0±2,8ng/ml. Houve declínio (PTo verify the effect of heat stress (HS on plasma testosterone, triiodothyronine (T3, and thyroxine (T4 concentrations, eight Saanen (n=4 and Alpine Brown (n=4 bucks were kept in climate chamber under thermal neutral conditions (13.0ºC to 26.7ºC for 30 days. After a resting period (60 days, the same bucks were submitted to heat stress (23.7ºC to 34.0ºC for another 30 days. To neutralize the seasonal variations of hormonal profiles throughout the period, the photoperiod was controlled every 30 days altering long (16 hours of light and 8 hours of darkness and short days (8 hours of light and 16 hours of darkness. The blood samples were collected twice a week during five weeks. In both breeds, there was no effect of HS (P>0.05 on plasma concentrations of testosterone (1.8±0.2 vs 1.3±0.2ng/ml and T4 (52.7±2.8 vs 50.0±2.8ng/ml. There was a decline (P<0.01 of plasma T3 concentrations (1.3±0.1 vs 1.0±0.1ng/ml after HS treatment, but this reduction was only

  6. Radioimmunoassay for measurement of thyroxine (T4) and triiodothyonine (T3) in blood serum

    International Nuclear Information System (INIS)

    Chopra, I.J.

    1975-01-01

    This invention relates to a highly accurate, rapid and simple estimation of thyroxine (T 4 ) directly from blood serum and also relates to the accurate measurement of triiodo-L-thyronine (T 3 ) directly from blood serum. More specifically, the invention relates to a rapid, specific and reliable radioimmunoassay (RIA) technique for measurement of both T 4 and T 3 in unextracted serum. The method requires very small amounts of serum, e.g., 25 microliters (μl) to measure T 4 concentration in nearly all specimens representing clinical states of eu-, hypo- and hyperthyroidism, and 250 μl to measure T 3 concentrations in specimens representing most clinical states

  7. Effect of adjuvant lithium on thyroxine (T4) concentration after radioactive iodine therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, Emmanuel NiiBoye; Vangu, Mboyo-Di-Tamba Heben Willy [University of the Witwatersrand, Division of Nuclear Medicine and Molecular Imaging, Department of Radiation Sciences, Johannesburg (South Africa)

    2016-10-15

    To study the effect of adjuvant lithium on serum thyroxine (T4) concentrations in patients treated with radioactive iodine (RAI) therapy in our environment. This was a prospective simple randomized comparative, experimental cohort study of patients with hyperthyroidism referred for RAI ablation therapy in the two main academic hospitals in Johannesburg between February 2014 and September 2015. Amongst the 163 participants in the final analysis, 75 received RAI alone and 88 received RAI with lithium. The difference in mean T4 concentrations at 3 months between the RAI-only group (17.67 pmol/l) and the RAI with lithium group (11.55 pmol/l) was significant with a small effect size (U = 2328.5, Z = -2.700, p = 0.007, r = 0.01). Significant decreases in T4 concentrations were observed as early as 1 month after RAI (p = 0.0001) in the RAI with lithium group, but in the RAI-only group, significant decreases in T4 concentrations were observed only at 3 months after RAI therapy (p = 0.000). Women and patients with Graves' disease who received RAI with adjuvant lithium also showed significant decreases in T4 concentrations at 1 month (p = 0.002 and p = 0.003, respectively). Adjuvant lithium leads to an earlier and better response to RAI therapy with lower T4 concentrations that are achieved earlier. This earlier response and decrease in T4 concentrations were noted in patients with Graves' disease and nodular goitre, and in women with hyperthyroidism who received adjuvant lithium therapy. (orig.)

  8. The peripheral conversion of thyroxine (T4) into triiodothyronine (T3) and reverse triiodothyronine (rT3)

    International Nuclear Information System (INIS)

    Wiersinga, W.M.

    1979-01-01

    The aim of this study was to delineate several physiological, pathological and pharmacological factors involved in the peripheral conversion of thyroxine (T 4 ), using radioimmunoassay. The determination of normal values of these tests under basal circumstances and after stimulation with thyrotropin-releasing-hormone is presented, and some physiological factors which may modulate the conversion of T 4 are discussed. Results are presented of the thyroid function tests in patients with thyroid disease and with acute non-thyroidal diseases. (Auth.)

  9. Thyroxine (T 4-RIA) and triiodothyronine (T 3-RIA) serum levels in sheep fed on Leucaena Leucocephala

    International Nuclear Information System (INIS)

    Pessoa, J.M.; Rodriguez, N.M.; Cardoso, W.M.; Velez, C.E.S.

    1988-01-01

    The aim of this work is to study the toxicity of Leucaena leucocephala on thyroxine and triiodothyronine serum concentration. Results indicate that ovine T 4 and T 3 serum levels do not decrease with Leucaena leucocephala feeding, sohen proreided for 41 days. (author). 10 refs, 1 tab

  10. Effect of thyroxine on cellular oxygen-consumption and glucose uptake: evidence of an effect of total T4 and not "free T4"

    DEFF Research Database (Denmark)

    Kvetny, J; Matzen, L E

    1990-01-01

    Recent studies of cellular T4 and T3 uptake have indicated active transport of the hormones into the cell rather than passive diffusion of the non-protein bound fraction. In order to study the significance of the extracellular environment, oxygen consumption and glucose uptake were examined...... in human mononuclear blood cells. Cells were incubated in protein free medium and in human serum totally depleted of thyroid hormones by resin treatment and fixed amounts of T4 (total T4 = 0-50-100-5000 nmol/l; free T4 = 0-5-11-5600 pmol/l) were added. Thyroxine stimulated glucose uptake and oxygen......-consumption in a dose dependent manner but the T4 stimulation was dependent on the total concentration of T4 and did not differ between serum incubation or non-protein containing medium. Addition of ANS (100 mg/l) which inhibits binding of T4 to TBG, did not increase T4 effect in serum. Inhibition of the Na...

  11. Circadian variations of thyrotropin (TSH), triiodothyronine (T3) and thyroxine (T4) in surgical and functional pinealectomy in rats

    International Nuclear Information System (INIS)

    Ostrowska, Z.; Zwirska-Korczala, K.; Buntner, B.; Jarzab, B.; Kucharzewski, M.

    1994-01-01

    The aim of the present study was to determine the regulatory influence of surgical and functional pinealectomy on circadian variations of thyrotropin (TSH), triiodothyronine (T 3 ) and thyroxine (T 4 ) in male Wistar rats. The serum hormone levels were estimated with RIA method, and the circadian rhythm secretion was analyzed by means of cosinor method. Our study shows that there are marked differences in circadian fluctuations of T 3 and T 4 between the two generally used models of pinealectomy. (author). 55 refs, 4 figs

  12. Simultaneous measurement of thyroxine and triiodothyronine in trout plasma using a solid-phase radioimmunoassay

    International Nuclear Information System (INIS)

    Omeljaniuk, R.J.; Cook, R.F.; Eales, J.G.

    1984-01-01

    A solid-phase radioimmunoassay (RIA) employing miniature G-25 Sephadex columns and a single isotope was evaluated for simultaneous measurement of T 3 (3,5,3'-triiodo-L-thyronine) and T 4 (L-thyroxine) in trout plasma. The method was judged reliable based on the characteristics of the standard curves, the high and consistent recoveries of T 3 (87.0 or 86.7 percent) and T 4 (103 or 98 percent) added either singly or in combination, low inter-( 3 and T 4 after plasma dilution, and acceptable correlations between hormone values obtained using either the simultaneous or single RIA methods (rsub(T3) = 0.89; rsub(T4) = 0.91). It is concluded that the simultaneous RIA with its savings in time, plasma volume, and reagents can be used to advantage to measure T 3 and T 4 in plasma of trout and presumably other vertebrates

  13. Selenium deficiency inhibits the conversion of thyroidal thyroxine (T4) to triiodothyronine (T3) in chicken thyroids.

    Science.gov (United States)

    Lin, Shi-lei; Wang, Cong-wu; Tan, Si-ran; Liang, Yang; Yao, Hai-dong; Zhang, Zi-wei; Xu, Shi-wen

    2014-12-01

    Selenium (Se) influences the metabolism of thyroid hormones in mammals. However, the role of Se deficiency in the regulation of thyroid hormones in chickens is not well known. In the present study, we examined the levels of thyroidal triiodothyronine (T3), thyroidal thyroxine (T4), free triiodothyronine, free thyroxine (FT4), and thyroid-stimulating hormone in the serum and the mRNA expression levels of 25 selenoproteins in chicken thyroids. Then, principal component analysis (PCA) was performed to analyze the relationships between the selenoproteins. The results indicated that Se deficiency influenced the conversion of T4 to T3 and induced the accumulation of T4 and FT4. In addition, the mRNA expression levels of the selenoproteins were generally decreased by Se deficiency. The PCA showed that eight selenoproteins (deiodinase 1 (Dio1), Dio2, Dio3, thioredoxin reductase 2 (Txnrd2), selenoprotein i (Seli), selenoprotein u (Selu), glutathione peroxidase 1 (Gpx1), and Gpx2) have similar trends, which indicated that they may play similar roles in the metabolism of thyroid hormones. The results showed that Se deficiency inhibited the conversion of T4 to T3 and decreased the levels of the crucial metabolic enzymes of the thyroid hormones, Dio1, Dio2, and Dio3, in chickens. In addition, the decreased selenoproteins (Dio1, Dio2, Dio3, Txnrd2, Seli, Selu, Gpx1, and Gpx2) induced by Se deficiency may indirectly limit the conversion of T4 to T3 in chicken thyroids. The information presented in this study is helpful to understand the role of Se in the thyroid function of chickens.

  14. The colloidal thyroxine (T4) ring as a novel biomarker of perchlorate exposure in the African clawed frog Xenopus laevis

    Science.gov (United States)

    Hu, F.; Sharma, Bibek; Mukhi, S.; Patino, R.; Carr, J.A.

    2006-01-01

    The purpose of this study was to determine if changes in colloidal thyroxine (T4) immunoreactivity can be used as a biomarker of perchlorate exposure in amphibian thyroid tissue. Larval African clawed frogs (Xenopus laevis) were exposed to 0, 1, 8, 93, and 1131 ??g perchlorate/l for 38 and 69 days to cover the normal period of larval development and metamorphosis. The results of this study confirmed the presence of an immunoreactive colloidal T4 ring in thyroid follicles of X. laevis and demonstrated that the intensity of this ring is reduced in a concentration-dependent manner by perchlorate exposure. The smallest effective concentration of perchlorate capable of significantly reducing colloidal T4 ring intensity was 8 ??g perchlorate/l. The intensity of the immunoreactive colloidal T4 ring is a more sensitive biomarker of perchlorate exposure than changes in hind limb length, forelimb emergence, tail resorption, thyrocyte hypertrophy, or colloid depletion. We conclude that the colloidal T4 ring can be used as a sensitive biomarker of perchlorate-induced thyroid disruption in amphibians. ?? Copyright 2006 Oxford University Press.

  15. Thyroxine (T4) radioimmunoassay using filter paper dried blood sample: an attempt for screening of neonates for hypothyroidism

    International Nuclear Information System (INIS)

    Afroz, S.; Hussain, R.; Ahmed, K.

    1997-01-01

    This paper describes a sensitive but simple and less expensive method suitable for estimation of thyroxine (T 4 ) level. Deficiency of iodine during fetal life results in neonatal hypothyroidism and critinism. Frequency of neonatal hypothyroidism is 1 in 5000 to 7000 in countries having iodine deficiency. It is therefore important to diagnose the neonatal hypothyroidism as soon as possible after birth. The estimation of thyroxine has been found to the a reliable index for diagnosis of hypothyroidism and has long been used for screening of neonatal hypothyroidism. In the present study, instead of serum sample, a 6 mm disc of filter paper containing dried blood sample was used. The test was carried out in the laboratory with 40 samples. As compared to the sensitivity of serum sample technique which is 15.19 n mol/L, the filter paper technique has the sensitivity of 17.23 n mol/L. The work revealed that the T 4 concentration do not depend upon the amount of blood on the filter paper. Effect of temperature on filter paper disc was evaluated at 4 o c, at 25 o c and at 37 o c. Results obtained showed significant variation and the best result was obtained for the sample kept at 4 o c. The method is simple, rapid, less expensive and needs a small amount of blood and is, therefore, a useful technique for mass screening of neonatal hypothyroidism. 6 refs., 4 tables (author)

  16. Effect of melatonin supplementation on plasma vasopressin response to different conditions in rats with hyperthyroidism induced by L-thyroxine.

    Science.gov (United States)

    Mogulkoc, Rasim; Baltaci, Abdulkerim Kasim

    2010-04-09

    The present study was performed to determine how basal, isotonic, hypertonic and hypovolemic conditions affect fluid-electrolyte balance and plasma arginine vasopressin (AVP) levels in rats with experimental hyperthyroidism supplemented with melatonin. The rats were divided into four groups of twenty-four subjects each kept under the following treatments during one month: (1) Controls; (2) treated with L-thyroxine; (3) treated with L-thyroxine and sham melatonin and (4) treated with L-thyroxine and melatonin. After this each group was further subdivided into subgroups that were subject to normal, isotonic, hypertonic and hypovolemic conditions. The plasma AVP, total triiodothyronine (TT(3)), total thyroxine (TT(4)) and melatonin levels were measured in plasma by means of a Phoenix Pharmaceutical RIA test kit. Hematocrit and osmolality levels were also determined. There were significant increases of total T3 and T4 levels in the L-thyroxine treated groups, p<0.001. The AVP levels were also increased in groups 2 and 3, but not so in the rats treated with melatonin (p<0.001), which also showed increased plasma melatonin levels (p<0.001). These results indicate that treatment with L-thyroxine increases stimulated and non-stimulated AVP release that are inhibited by melatonin supplementation. It was also shown that AVP response to hypertonic and hypovolemic conditions was not affected by L-thyroxine treatment and/or L-thyroxine+melatonin treatment. Copyright 2009 Elsevier B.V. All rights reserved.

  17. A Clinical Study on 125IT3 Resin Uptake Rate and Serum Thyroxin(T4) in Hyperthyroidism

    International Nuclear Information System (INIS)

    MooN, Ern Soo; Park, Yoh Han; Cho, Chang Ho; Park, In Soo; Lee, Chong Suk; Lee, Hak Choong

    1978-01-01

    Hyperthyroidism may be defined as those clinical conditions which result from an increase in the circulating levels of one or both thyroid hormones. Hyperthyroidism in broad sense could be classified with toxic diffuse goiter, toxic adenomatous goiter, and toxic multinodular goiter on the basis of the circulating thyroid hormone levels. For this study, the subject included 94 cases with hyperthyroidism were presented in 77 with toxic diffuse goiter, 8 with toxic adenomatous goiter, and 9 with toxic multinodular goiter on the levels of 125 IT 3 resin uptake rate and serum thyroxine (T 4 ). The observed results were as follows: 1) In the cases of hyperthyroidism including toxic diffuse goiter, toxic adenomatous goiter, and toxic multinodular goiter, 20.21% of the patients were male and 79.79% female. The majority of the patients were in 2nd to 4th decades of their lives. 2) There were objective signs clearly manifested in hyperthyroidism including toxic diffuse goiter and toxic adenomatous goiter which were rare in the multinodular goiter. The clinical signs in toxic diffuse and toxic adenomatous goiter included wide pulse pressure, tachycardia, systolic murmur, exophthalmos, tremor and warm skin etc. 3) The most frequent complaints of the patients with hyperthyroidism were palpitation, weight loss, increased appetite, perspiration, heat intolerance, nervousness, exertional dyspnea, and menstrual disturbance etc. There was no clear difference in the incidence of symptoms between toxic diffuse goiter and toxic adenomatous goiter, but there was clear difference between toxic multinodular goiter. 4) Considering of results of 125 IT 3 resin uptake rate and serum T 4 level in toxic diffuse goiter, toxic adenomatous goiter and toxic multinodular goiter, 125 IT 3 resin uptake rate was 49.15±9.94% (mean) and serum T 4 21.29±7.04 ug/dl (mean) in toxic diffuse goiter. In toxic multinodular goiter, 125 I T 3 resin uptake rate was 32.47±6.74% (mean) and serum T 4 level 11.03

  18. Serum levels of triiodothyronine (T3) and thyroxine (T4) in buffalo (Bubalus bubalis Lin.) raised in Amazon region

    International Nuclear Information System (INIS)

    Silva, A.O.A. da.

    1991-08-01

    Through the use of radioimmunoassay (RIA) it was determined blood serum concentration of triiodothyronine (T 3 ) and thyroxine (T 4 ) (n=78) for two different water buffalo racial groups. Blood serum was collected from young and adult animals belonging to two farms in Castanhal country, state of Para, Brazil, through the year of 1988. The serum levels of T 3 and T 4 were statistically correlated with climatic parameters, e.g., pluviometric precipitation, environmental temperature, humidity, light intensity variation and physiological factors such as age, breed and sex. It was identified two seasons during experiment, one season the rainfall period with high precipitation rates and the other one was considered as dry season, with low precipitation rates. The average rate of temperature and humidity have shown no significant statistic difference between the two seasons. On the other hand, it was found a significant relationship between luminosity and seasons, since when the luminosity decreases the pluviometric rates increases. (author). 51 refs, 15 figs, 15 tabs

  19. Thyroxine (T 4-RIA) and triiodothyronine (T 3-RIA) serum levels in sheep fed on Leucaena Leucocephala; Niveis sericos de tiroxina (T4-RIA) e triiodotinonina (T3-RIA) em ovinos alimentados cm Leucaena Leucocephala LAM

    Energy Technology Data Exchange (ETDEWEB)

    Pessoa, J M; Rodriguez, N M [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Escola de Veterinaria; Cardoso, W M [Maranhao Univ., Sao Luis, MA (Brazil). Escola de Medicina Veterinaria; Velez, C E.S.

    1988-12-31

    The aim of this work is to study the toxicity of Leucaena leucocephala on thyroxine and triiodothyronine serum concentration. Results indicate that ovine T 4 and T 3 serum levels do not decrease with Leucaena leucocephala feeding, sohen proreided for 41 days. (author). 10 refs, 1 tab.

  20. Measurement of serum free thyroxine using fT4(fraction) determined by solidphase radioimmunoassay: First clinical results

    International Nuclear Information System (INIS)

    Reiners, C.; Walter, H.; Moll, E.; Boerner, W.

    1983-01-01

    The novel solidphase RIA SPAC ET permits the simultaneous determination of TF 4 , TT 4 and fT 4 -fraction. The duration until the complete results of this assay can be obtained is a little bit less than for parallel radioimmunologic FT 4 - and TT 4 -determinations. The results of our quality control survey indicate that the precision of the precommercial kits tested should be improved. In addition, the normal range of FT 4 from 5.5 pg/ml to 12.5 pg/ml should be adapted in the final assay version of the approximately 30% higher normal ranges which are common with alternative FT 4 -radioimunoassays. In comparison to FT 4 -I, TT 4 /TBG-ratio and other FT 4 -radioimmunoassays, the diagnostic accuracy of FT 4 determined by SPAC ET is equally good. Estrogen-mediated TBG elevations on oral contraceptives are well compensated. In pregnancy, the known tendency towards lower FT 4 levels can be seen with the beginning of the second trimester. While there are no changes of FT 4 levels on medication with acetylosalicyclic acid, a slight tendency towards lower FT 4 determined by SPAC ET can be seen on therapy with phenytoin. Under treatment with heparin, FT 4 by SPAC ET is elevated. This is more reasonable than the decreases of FT 4 concentrations observed with radioimmunoassays using FT 4 analogues as tracers. RIA SPAC ET is an interesting alternative to routinely used direct and indirect methods for determination of free thyroxine. (orig.) [de

  1. Thyroxine (T4) Test

    Science.gov (United States)

    ... K. Brunner & Suddarth's Handbook of Laboratory and Diagnostic Tests. 2 nd Ed, Kindle. Philadelphia: Wolters Kluwer Health, Lippincott Williams & Wilkins; c2014. Thryoxine, Serum 485 p. Lab Tests ...

  2. Dissociation between plasma concentrations of thyroxine and insulin-like growth factor-I.

    Science.gov (United States)

    Dauncey, M J; Morovat, A; Rudd, B T; Shakespear, R A

    1990-09-01

    The relation between plasma concentrations of thyroxine (T4) and insulin-like growth factor-I (IGF-I) has been examined in young, growing pigs under controlled conditions of energy intake. Compared with euthyroid controls, plasma levels of IGF-I were significantly elevated (P less than 0.005) both in hypothyroid animals on the same food intake and in hyperthyroid animals on double the food intake. There was however no increase in IGF-I in a hyperthyroid group on the control level of intake. Contrary to previous reports in which energy intake was not controlled, it is concluded that there is no simple correlation between plasma concentrations of T4 and IGF-I.

  3. Influence of D-thyroxine on plasma thyroid hormone levels and TSH secretion

    International Nuclear Information System (INIS)

    Gless, K.H.; Oster, P.; Huefner, M.; Heidelberg Univ.

    1977-01-01

    Triiodothyronine (T 3 ), thyroxine (T 4 ), basal TSH and TSH after stimulation with TRH were determined by labelling with Iodine 127 in healthy subjects and patients treated with D-thyroxine (DT 4 ). After a dosage of 6 mg DT 4 , the D/L T 4 plasma concentration rose about 4-fold 4 hours after application and was only moderately elevated 14 hours later. To achieve constantly elevated T 4 levels, 3 mg DT 4 were applied in the further experiment every 12 hours. The D/L T 4 plasma concentration rose 2.5-4-fold, and there was a small but significant increase of the D/L T 3 plasma concentration. 74 hours after onset of treatment basal TSH was below detecable limits and the increase of TSH 30 min after injection of 200 μg TRH (TRH test) was only about 15% compared to zero time. The time course of TSH suppression was investigated after treatment with DT 4 and LT 4 (single dosage of 3 mg). TRH-tests were performed before, 10, 26, 50 and 74 hours after the first dosage of D or LT 4 . There was no difference in the time course of basal TSH and TSH stimulated by TRH. In 10 patients on DT 4 longterm therapy, basal and stimulated TSH were found to be below the detectable limits of 0.4 μg/ml. Our results show that (1) plasma half-life of DT 4 is less than 1 day, (2) TSH suppression after D and LT 4 treatment is very similar, and (3) in patients on lang-term DT 4 treatment, TSH plasma concentration is below detectable limits even after stimulation with TRH. (orig.) [de

  4. A novel formulation of L-thyroxine (L-T4) reduces the problem of L-T4 malabsorption by coffee observed with traditional tablet formulations.

    Science.gov (United States)

    Vita, Roberto; Saraceno, Giovanna; Trimarchi, Francesco; Benvenga, Salvatore

    2013-02-01

    The purpose of this work is to evaluate if the coffee-associated malabsorption of tablet levothyroxine (L-T4) is reduced by soft gel capsule. We recruited 8 patients with coffee-associated L-T4 malabsorption including one hypothyroid patient. For 6 months, the patients were switched to the capsule maintaining the L-T4 daily dose. Patients took the capsule with water, having coffee 1 h later (proper habit, PH) on days 1-90, or with coffee ≤ 5 min later (improper habit, IH) on days 91-180. After 6 months, 2 patients volunteered for an acute loading test of 600 μg L-T4 (capsule) ingested with water (PH) or with coffee (IH). In the single hypothyroid patient, the post-switch TSH ranged 0.06-0.16 mU/L (PH) versus 5.8-22.4 mU/L pre-switch (PH) and 0.025-0.29 mU/L (IH) versus 26-34 mU/L pre-switch (IH). In the other 7 patients, post-switch TSH was 0.41 ± 0.46 (PH) versus 0.28 ± 0.20 pre-switch (PH) (P = 0.61) and 0.34 ± 0.30 (IH) versus 1.23 ± 1.47 pre-switch (IH) (P coffee influenced L-T4 pharmacokinetics minimally. Soft gel capsules can be used in patients who are unable/unwilling to change their IH of taking L-T4.

  5. Effects of L-thyroxine on plasma biochemistry in broiler chicks (Gallus gallus)

    International Nuclear Information System (INIS)

    Chaudhry, M.A.; Siddiqui, Z.H.; Imran, M.; Ahsan, M.

    2009-01-01

    The effect of a single intraperitoneal injection of a low dose (1 mu g/g) and a high dose (4 mu /g) of thyroxine (T 4) were investigated with time on plasma metabolites in broiler (Hubbard) chicks. Plasma total proteins, albumin fraction, glucose and triglyceride levels were decreased significantly in both experimental groups. The plasma cholesterol values remained almost comparable with controls during the early stages of the experiment but after 72 hours of the experiment higher dose of T 4 resulted in a significant (p<0.01) decrease followed by significant (p<0.05) increase in the same experimental group. The plasma albumin fraction decreased significantly in animals injected with higher dose of T/sub 4/ after 24 hours and the same trend continue even after 72 hour of the experiment. Plasma uric acid values were significantly decreased in group administered with lower dose of T/sub 4/ after 12 hours of the post injection time. However in animals administered with higher dose of thyroid hormone reflected a significant increase in plasma uric acid levels after 12 hours of the experiment and its levels were significantly decreased after 48 hours. The results are discussed in the light of previous reports of thyroid hormones and their physiological implications in different vertebrate groups. (author)

  6. A clinical study on 125I T3 resin uptake rate and serum thyroxin (T4) in hyperthyroidism

    International Nuclear Information System (INIS)

    Moon, E.S.; Park, Y.H.; Cho, C.H.; Park, I.S.; Lee, C.S.; Lee, H.C.

    1978-01-01

    Total of 94 cases of hyperthyroidism were classified as toxic diffuse goiter (77 case) as toxic adematous goiter (8 case) and as toxic multinodular goiter (9 case) on the levels of T 3 - 125 I resin uptake rate and the measurement of serum T 4 levels. Various clinical symptoms and diagnostic characteristics were discussed. (author)

  7. Effects of thyroxine (T4) and triiodothyronine (T3) on the thyrotropin (TSH) response to TSH-releasing hormone (TRH) in the rat

    International Nuclear Information System (INIS)

    Boado, R.J.; Ulloa, E.R.; Zaninovich, A.A.

    1982-01-01

    Wistar rats were treated with 7.8 or 260 nmols T4/100 g BW, 1.5 or 260 nmols T3/100 g BW, or saline as control. Twenty minutes later 1 μg TRH/100 g BW was injected iv. Heparinized blood samples were drawn at times 0 and 30 minutes (10 min post-TRH) for determination of plasma TSH, T4 and T3 by RIA. Other group of rats were administered with 150 μCi of 3',5'- 125 I-T4 prepared by iodination of 3,5-diiodothyronine. Thirty minutes later the hypophyses were removed, and chromatographed. Other group of animals were treated with 5 mg of iopanoic acid (IOP)/100 g BW. Thereafter, rats were injected iv with 260 nmols T4 or T3/100 g BW and the TRH-test performed as described above. In the control group there was a 11-fold increase in plasma TSH at 10 minutes post-TRH. In rats treated with 260 nmols T4 the post-TRH increment in plasma TSH was 5+-1-fold (p 125 I-T3 in the hypophyses 30 minutes after 125 I-T4 administration. The present data indicate that T4 is capable of depressing the release of TSH in response to TRH stimulation in normal rats. (M.E.L.) [es

  8. Comparison of serum levels of Tri‐iodothyronine (T3, Thyroxine (T4, and Thyroid‐Stimulating Hormone (TSH in preeclampsia and normal pregnancy

    Directory of Open Access Journals (Sweden)

    Nayereh Khadem

    2012-01-01

    Full Text Available Background: The physiological changes in thyroid gland during pregnancy have been suggested as one of the pathophysiologic causes of preeclampsia.Objective: The aim of this study was comparison of serum levels of Tri‐iodothyronine (T3, Thyroxine (T4, and Thyroid‐Stimulating Hormone (TSH in preeclampsia and normal pregnancy. Materials and Methods: In this case‐control study, 40 normal pregnant women and 40 cases of preeclampsia in third trimester of pregnancy were evaluated. They were compared for serum levels of Free T3 (FT3, Free T4 (FT4 and TSH. The data was analyzed by SPSS software with the use of t‐student, Chi‐square, Independent sample T-test and Bivariate correlation test. p≤0.05 was considered statistically significant. Results: The mean age was not statistically different between two groups (p=0.297. No significant difference was observed in terms of parity between two groups (p=0.206. Normal pregnant women were not significantly different from preeclampsia cases in the view of FT3 level (1.38 pg/ml vs. 1.41 pg/ml, p=0.803, FT4 level (0.95 pg/ml vs. 0.96 pg/ml, p=0.834 and TSH level (3.51 μIU/ml vs. 3.10 μIU/ml, p=0.386. Conclusion: The findings of the present study do not support the hypothesis that changes in FT3, FT4 and TSH levels could be possible etiology of preeclampsia

  9. Method for the determination of a new indicator proportional to the plasma concentration of free thyroxine

    International Nuclear Information System (INIS)

    Deutsch, G.

    1979-11-01

    A novel method for the estimation of free thyroxine (T 4 ) in serum is described. Partially heat-denatured serum is mixed with 125 I-labelled T 4 bound to thyroxine-binding globulin (TBG) on a Sephadex column. After a period of equilibration, the column is eluted with buffer and the residual radioactivity on the column measured. This represents the fraction of 125 I-labelled T 4 freed from TBG and can be related to the concentration of free T 4 in the serum, being expressed as ''proportional free thyroxine'' (PFT 4 ) in μg per 100 ml. In studies of the method, a coefficient of variation of 4.52% in the results was found. The mean PFT 4 value in 124 normal subjects was 7.26 +- 1.25 μg per 100 ml. Values below 4.8 μg per 100 ml were considered indicative of hypothyroidism and those above 9.8 μg per 100 ml indicative of hyperthyroidism, in good agreement with clinical findings. The coefficient of correlation between the results and results obtained by the AMES ''Tetralute'' method was 0.911. The mean PFT 4 value in 37 pregnant subjects was 12.2 +- 2.1 μg per 100 ml

  10. Serum levels at moment of breeding of triiodothyronine (T3), thyroxine (T4), and progesterone in Saanen goats females during normal and induced heat and testosterone in 12 Saanen goats males

    International Nuclear Information System (INIS)

    Prestes, Nereu C.; Vulcano, Luiz C.; Mamprim, Maria J.; Oba, Eunice

    1996-01-01

    The aim of this experiment was to measure the level of triiodothyronine(T 3 ), thyroxine(T 4 ) and progesterone in the serum of females Saanen goats. The progesterone levels were: 0.59 and 0.79 ng/μl considering breeding during normal and induced heat respectively. The T 3 values were: 192.8 and 251.32 ng/dl while T 4 values were: 36.38 and 31.68 ng/dl in the same condition above. The average testosterone level at the moment of breeding in the serum of 12 males was 1.38 pg/ml. (author)

  11. Conception of dairy cows in different seasons of the year in relation to thyroxine (T4) and triiodothyronine (T3) concentrations

    International Nuclear Information System (INIS)

    Bekeova, E.; Elecko, J.; Hendrichovsky, V.; Hajurka, V.; Choma, J.; Krajnicakova, M.

    1989-01-01

    The investigation took place in March, June and November following estrus synchronization with cloprostenol. The concentrations of thyroxine and triiodothyronine in the blood serum were determined by RIA using commercial kits. It is derived from the results that conception of dairy cows is in indirect proportion to the thyroid hormone levels. (M.D.). 4 figs., 4 tabs., 22 refs

  12. The effect of control of diabetes mellitus on plasma T4, T3, rT3 levels and half muscle relaxation period

    International Nuclear Information System (INIS)

    Ismail, A.A.; Hafiez, A.A.; Sayed, S.N.; Abbas, E.Z.; Halawa, F.A.; Youssef, M.M.

    1984-01-01

    25 diabetics of the maturity onset type who showed no clinical evidence of either peripheral neruropathy or diabetic amyotrophy were selected for this study. All patients were subjected to the following investigations: estimation of half muscle relaxation period of the quadriceps muscle knee-jerk, measurement of plasma levels of thyroxine (T 4 ), triiodothyronine (T 3 ) and reverse triiodothronine (rT 3 ), determination of fasting and two hours postprandial blood sugar levels. The quadriceps muscle relaxation period in uncontrolled diabetics was significantly longer than in normals. Control of diabetes by glibenclamide or gliclazide did not cause a significant change in muscle relaxation period. There was also no significant difference between the effects of the two drugs. (author)

  13. The concentration of glucose, insuline, thyroxine (T4), triiodthyronine (T3) and gastrine in the maternal blood, in the umbilical cord blood of their outcomes in the neonatal blood samples

    International Nuclear Information System (INIS)

    Osuch-Jaczewska, R.; Tomala, J.; Adamska, S.; Bielecka, W.; Mikulska, M.; Kalacinska, M.; Sieron, G.

    1978-01-01

    In the blood samples collected from the mothers, from the umbilical cord of their outcomes and from these neonates after 24 hours of life following estimations were performed collaterally: The concentration of insulin in 50 mothers and their fetuses and in 34 neonates, concentration of thyroxine (T 4 ) in 70 mothers and their fetuses and in 32 neonates, triiodothyronine binding coefficient (WWT 3 ) in 60 mothers and their fetuses and neonates, concentration of gastrine in 23 mothers and their fetuses and in 5 neonates. Besides that the concentration of glucose in total blood was established in 300 mothers - their fetuses and neonates. The insuline, WWT 3 and gastrine were estimated by radioimmune techniques and T 4 by radiocompetitive technique. The glucose concentration - with the aid of o-toluidine method. Basing on the results, the paper suggests that the fetus and the newborn represent independent unit in the aspect of regulation of the glucose concentration, secretion of insuline, T 3 , T 4 and gastrine, notwithstanding the possibility of transplacental passage of these hormones exists the correlation coefficients between the maternal and fetal blood concentrations of insuline, T 4 and WWT 3 were significant. The cord-blood glucose concentration exhibits a marked correlation with the maternal glicemia. Physiologic, asymptomatic hyperinsulinemia and hyperthyreosis and an increase of gastrine concentration demonstrate the presence, in the fetal and neonatal organisms, of certain compensatory-regulating mechanisms stimulating and inhibiting with feed-back properties, which guarantee the environmental homeostasis. (author)

  14. Plasma corticosterone and thyroxine concentrations during chronic ingestion of crude oil in mallard ducks (Anas platyrhynchos)

    Science.gov (United States)

    Rattner, B.A.; Eastin, W.C.

    1981-01-01

    1. Blood samples were collected from mallard ducks after 6, 12, and 18 weeks of dietary exposure to mash containing 0.015%, 0.150%, and 1.500% crude oil.2. Plasma corticosterone concentrations in ducks fed mash containing 0.150% or 1.500% Alaskan Prudhoe Bay crude oil were uniformly depressed when compared to values in untreated control birds.3. Plasma thyroxine concentration was not altered in ducks chronically exposed to crude oil.4. The observed alteration in corticosterone concentration could reduce tolerance to temperature and dietary fluctuations in the environment.

  15. Comparative characterization of thyroid hormone receptors and binding proteins in rat liver nucleus, plasma membrane, and cytosol by photoaffinity labeling with L-thyroxine

    International Nuclear Information System (INIS)

    Dozin, B.; Cahnmann, H.J.; Nikodem, V.M.

    1985-01-01

    Photoaffinity labeling with underivatized thyroxine (T4) was used to identify and compare the T4 binding proteins in rat liver cytosol, nuclear extract, and purified plasma membrane. When these subcellular fractions were incubated with a tracer concentration of [125I]T4, irradiated with light above 300 nm, and individually analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the radioactivity profiles revealed the presence of T4 binding proteins of molecular masses of 70, 52, 43, 37, 30, and 26 kilodaltons (kDa) in cytosol, of 96, 56, 45, and 35 kDa in nuclear extract, and of 70, 44, and 30 kDa in plasma membrane. Competition experiments performed in the presence of a 1000-fold excess of unlabeled T4 demonstrated that these binding proteins display different hormone binding activities. The similar electrophoretic mobilities of some binding proteins present in the different subcellular fractions, i.e., the 70-, 43-45-, and 30-kDa proteins, suggested that these proteins might be identical. However, double-labeling experiments in which plasma membrane, nuclear extract, and cytosol were photolabeled with either [125I] or [131I]T4 and mixed, two at a time, in all possible combinations showed that from one cellular fraction to another, the radioactivity peaks corresponding to the approximately 70-, 43-45-, and 30-kDa proteins were not superimposed. Their relative positions on the gel differed by one or two slices, which indicated differences in molecular mass of 1.9-3.6 kDa. Moreover, enzymatic digestion with Staphylococcus aureus V8 protease of these three proteins, prepared from each subcellular fraction, yielded dissimilar peptide patterns

  16. Thyroxine administration to infants of less than 30 weeks' gestational age does not increase plasma triiodothyronine concentrations

    NARCIS (Netherlands)

    van Wassenaer, A. G.; Kok, J. H.; Endert, E.; Vulsma, T.; de Vijlder, J. J.

    1993-01-01

    Very preterm infants (less than 30 weeks' gestational age) were treated with thyroxine in three different dosage schemes: 10, 8 and 6 micrograms.kg-1 birthweight.day-1 during the first 6 weeks of life. The aim was to prevent transient hypothyroxinemia of the preterm infant. Plasma levels of

  17. Combined radioimmunoassay for triiodothyronine and thyroxine

    International Nuclear Information System (INIS)

    Denning, C.E.; Schick, L.A.

    1980-01-01

    A method for the combined radioimmunoassay for the hormones triiodothyronine (T-3) and thyroxine (T-4) in serum or plasma, wherein the radiolabeled t-3 and t-4 reagents are t-3 and t-4 labeled with the same radioisotope. The hormones are extracted from the serum or plasma sample and separated from their binding proteins by adsorption to a crosslinked dextran gel at a highly alkaline ph. After washing away the dissociated proteins, a predetermined limiting amount of t-3 antibody is incubated with the gel and thereafter radiolabeled t-3 which has become extracted from the gel by antibody binding is washed away. Excess t-3 antibody and a predetermined limiting amount of t-4 antibody are then incubated with the gel and radiolabeled t-3 and t-4 which has become extracted from the gel by antibody binding are thereafter washed away. The respective relative amounts of radiolabeled t-3 and t-4 retained by the gel after the incubations with the respective limiting amounts of t-3 and t-4 antibody are compared with standard results to quantitate the hormones in the sample. The use of excess t-3 antibody in the t-4 antibody incubation is critical to the accuracy of the method, enabling the use of the same radioisotope for radiolabeling t-3 and t-4

  18. Dynamics of the plasma concentrations of TSH, FT4 and T3 following thyroxine supplementation in congenital hypothyroidism

    NARCIS (Netherlands)

    Bakker, Bert; Kempers, Marlies J. E.; de Vijlder, Jan J. M.; van Tijn, David A.; Wiedijk, Brenda M.; van Bruggen, Michael; Vulsma, Thomas

    2002-01-01

    OBJECTIVE The dynamics of the plasma concentrations of various diagnostic determinants of thyroid function were analysed in children with congenital hypothyroidism (CH) after the start of T4 supplementation. The description of the biochemical dynamics of TSH and free T4 (FT4) during the first period

  19. Free thyroxin by radioimmunoassay: evaluation of a new direct method involving a radiolabeled thyroxin analog

    International Nuclear Information System (INIS)

    Kubasik, N.P.; Lundberg, P.A.; Brodows, R.G.; Hallauer, G.D.; Same, D.G.; Lindstedt, G.; Bengtsson, C.; Nystroem, E.

    1983-01-01

    The first performance evaluation of a new direct method for free thyroxin (T4) in serum by radioimmunoassay, with use of coated tubes and a radioiodinated T4 analog (Diagnostic Products Corp.) is presented. The assay is precise and robust: within-run imprecision (CV), 3.1-6.6%; between-run imprecision, 4.0-7.9%; no demonstrable variation between technologists irrespective of experience with the method. No outliers were observed when we compared the free T4 results with serum total T4. Reference values are reported for a total of 1243 euthyroid subjects; there was no significant age effect on serum free T4 in women 26 to 72 years old. The biological variation was about +/- 35% of the mean (2 SD). Free T4 results are the same for serum and plasma. The assay performs well in hypothyroidism and hyperthyroidism, and distinguishes individuals with thyroid disease from normal individuals. Free T4 values in women taking oral contraceptives are normal. Depressed results were often observed in acute nonthyroidal illness and continuing pregnancy. These results were directly comparable with those of another commercial direct radiolabeled-T4 analog kit for free T4

  20. Effects of Hypothyroidism and Exogenous Thyroxine on ...

    African Journals Online (AJOL)

    Summary: Thyroxine (T4) is important in gut development and maturation, and its use in treating hypothyroidism is becoming more popular. This study was conducted to evaluate the effect of thyroidectomy and thyroxine replacement on some gastrointestinal organs. Ten out of 20 thyroidectomised rats received 100pg/kgbw ...

  1. Free serum thyroxine

    International Nuclear Information System (INIS)

    Degrossi, O.J.; Altschuler, Noe; Cabrejas, M.L. de; Pinkas, Mirta; Garcia del Rio, Hernan

    1982-01-01

    The use of radiommunoassay (RIA) tehcniques has increased the diagnosis of thyroid functional alterations. A solid phase RIA method for free thyroxine (FT4) measurement was tested. Serum FT4, Total T4, T3 and TSH were determined by radioimmunoassay in 179 subjects. One hundred twenty two patients were normal (8 to 75 years old); FT4 was 1.42 +- 0.03 ng/100 ml (avg. value and std. error). In 27 cases of thyrotoxicosis the values were 4.66 +- 0.48 ng/100 ml and in 15 cases of hypothyroidism 0.50 +- 0.06 ng/100 ml (statistics probability [es

  2. Conversion of the thyroxin (T4) in 3,5,3'-triiodothyronin (T3) and 3,3',5'-triiodothyronin (T3 reverse) in human leukocytes suspensions. Hyperthyroidism and hypothyroidism studies

    International Nuclear Information System (INIS)

    Bianco, A.C.; Douglas, C.R.; Marone, M.M.; Scalissi, N.M.; Correa, P.H.S.

    1984-01-01

    The peripheral metabolism of thyroid hormones was studied in suspensions of human leukocytes through the evaluation of in vitro generation of T 3 and rT 3 (RIA) from non-radioactive T 4 . Increased in vitro generation of T 3 and rT 3 was observed in suspensions from hyperthyroid patients, while a significant decrease was evidenced when leukocytes from hypothyroid patients were used. These alterations are apparently due to the excess and lack of thyroid hormones, respectively, since they could be reserved in both cases by specific clinical treatment. (author) [pt

  3. MMSET deregulation affects cell cycle progression and adhesion regulons in t(4;14) myeloma plasma cells

    Science.gov (United States)

    Brito, Jose L.R.; Walker, Brian; Jenner, Matthew; Dickens, Nicholas J.; Brown, Nicola J.M.; Ross, Fiona M.; Avramidou, Athanasia; Irving, Julie A.E.; Gonzalez, David; Davies, Faith E.; Morgan, Gareth J.

    2009-01-01

    Background The recurrent immunoglobulin translocation, t(4;14)(p16;q32) occurs in 15% of multiple myeloma patients and is associated with poor prognosis, through an unknown mechanism. The t(4;14) up-regulates fibroblast growth factor receptor 3 (FGFR3) and multiple myeloma SET domain (MMSET) genes. The involvement of MMSET in the pathogenesis of t(4;14) multiple myeloma and the mechanism or genes deregulated by MMSET upregulation are still unclear. Design and Methods The expression of MMSET was analyzed using a novel antibody. The involvement of MMSET in t(4;14) myelomagenesis was assessed by small interfering RNA mediated knockdown combined with several biological assays. In addition, the differential gene expression of MMSET-induced knockdown was analyzed with expression microarrays. MMSET gene targets in primary patient material was analyzed by expression microarrays. Results We found that MMSET isoforms are expressed in multiple myeloma cell lines, being exclusively up-regulated in t(4;14)-positive cells. Suppression of MMSET expression affected cell proliferation by both decreasing cell viability and cell cycle progression of cells with the t(4;14) translocation. These findings were associated with reduced expression of genes involved in the regulation of cell cycle progression (e.g. CCND2, CCNG1, BRCA1, AURKA and CHEK1), apoptosis (CASP1, CASP4 and FOXO3A) and cell adhesion (ADAM9 and DSG2). Furthermore, we identified genes involved in the latter processes that were differentially expressed in t(4;14) multiple myeloma patient samples. Conclusions In conclusion, dysregulation of MMSET affects the expression of several genes involved in the regulation of cell cycle progression, cell adhesion and survival. PMID:19059936

  4. Effects of obesity, total fasting and re-alimentation on L-thyroxine (T4), 3,5,3'-L-triiodothyronine (T3), 3,3',5'-L-triiodothyronine (rT3), thyroxine binding globulin (TBG), cortisol, thyrotrophin, cortisol binding globulin (CBG), transferrin, alpha 2-haptoglobin and complement C'3 in serum.

    Science.gov (United States)

    Scriba, P C; Bauer, M; Emmert, D; Fateh-Moghadam, A; Hofmann, G G; Horn, K; Pickardt, C R

    1979-08-01

    The effects of total fasting for 31 +/- 10 days followed by re-alimentation with an 800 calorie diet on thyroid function, i.e. T4,T3,rT3,RT3U (resin T3 uptake), and TSH, and on TBG levels in serum were studied sequentially in obese hospitalized patients (N=18). Additionally, cortisol, growth hormone, prolactin, parathyrin and free fatty acids were followed as hormonal and metabolic parameters, respectively. Further, CBG, transferrin, alpha 2-haptoglobin and complement C'3 were measured as representatives of other serum proteins. Results before fasting: T4, T3, TBG, cortisol, CBG, alpha 2-haptoglobin and complement C'3 of the obese patients were elevated when compared with healthy normal weight controls, whereas rT3, T4/TBG ratio, T3/TBG ratio, TSH, coritsol/cbg ratio, growth hormone, prolactin, parathyrin and transferrin of the obese group were normal. RT3U and fT4 index were decreased in the obese patients. Results during fasting: Significant decreases were observed during fasting for the following parameters -- T3, TBG, T3/TBG ratio, transferrin, alpha 2-haptoglobin complement C'3. rT3, T4/TBG ratio, RT3U, fT4 index and FFA increased. T4, tsh response to TRH stimulation, cortisol, CBG, cortisol/cbg ratio, parathyrin, growth hormone and prolactin did not change. Results during re-alimentation: T3, TBG, T3/TBG ratio, TSH response to TRH, transferrin, alpha 2-haptoglobin and complement C'3 increased. Conversely, fT3, RT3U, FFA, cortisol and cortisol/cbg ratio decreased whereas the other parameters did not change. 1) There is no evidence for primary hypothyroidism in obese patients during prolonged fasting and re-alimentation. 2) The rapid decrease of T3 and increase of RT3U after initiation of fasting are not fully explained by the observed slower decreases in TBG. 3) The alterations of T3, rT3 and RT3U resemble in their kinetics the changes in FFA levels. 4) Fasting reduced the levels of only certain serum proteins, interestingly TBG, transferrin, alpha 2

  5. Treating Hypothyroidism with Thyroxine/Triiodothyronine Combination Therapy in Denmark

    DEFF Research Database (Denmark)

    Michaelsson, Luba Freja; Medici, Bjarke Borregaard; la Cour, Jeppe Lerche

    2015-01-01

    BACKGROUND: Five to ten percent of patients with hypothyroidism describe persistent symptoms despite being biochemically well regulated on levothyroxine (L-T4). Thyroxine (T4)/triiodothyronine (T3) combination therapy [L-T4/liothyronine (L-T3) or desiccated thyroid] are still regarded as experime......BACKGROUND: Five to ten percent of patients with hypothyroidism describe persistent symptoms despite being biochemically well regulated on levothyroxine (L-T4). Thyroxine (T4)/triiodothyronine (T3) combination therapy [L-T4/liothyronine (L-T3) or desiccated thyroid] are still regarded...

  6. Serum Thyroxine to Thyroxine-Binding Globulin Ratio in Pregnancy and Newborn

    International Nuclear Information System (INIS)

    Kim, Ji Yeul

    1982-01-01

    To evaluate the diagnostic value of the ratio of serum thyroxine(T 4 ) /thyroxine-binding globulin (TBG) for the thyroid status in pregnancy and newborn serum thyroxine, TBG, triiodothyronine, and free thyroxine levels were radioimmunoassayed in normal pregnant women at each of the trimesters, and the calculated serum T 4 /TBG ratios were compared with other parameters such as T 3 /TBG ratio and free T 4 /TBG ratio and free T 4 /TBG ratio. Serum T 4 levels were elevated with the proportionate increase in TBG levels during pregnancy, leading to the nearly constant value of serum T 4 /TBG ratios as in normal non-pregnant controls. In contrast, serum T 3 /TBG and free T 4 /TBG ratios varied considerably during pregnancy. In newborn, T 4 levels were nearly not changed with compared non-pregnant control value and TBG levels were elevated. The results indicate that serum T 4 /TBG ratio is a better parameter than others in evaluating the thyroid status during pregnancy and but newborn is a no better.

  7. Biosensor discovery of thyroxine transport disrupting chemicals

    International Nuclear Information System (INIS)

    Marchesini, Gerardo R.; Meimaridou, Anastasia; Haasnoot, Willem; Meulenberg, Eline; Albertus, Faywell; Mizuguchi, Mineyuki; Takeuchi, Makoto; Irth, Hubertus; Murk, Albertinka J.

    2008-01-01

    Ubiquitous chemicals may interfere with the thyroid system that is essential in the development and physiology of vertebrates. We applied a surface plasmon resonance (SPR) biosensor-based screening method for the fast screening of chemicals with thyroxine (T4) transport disrupting activity. Two inhibition assays using the main thyroid hormone transport proteins, T4 binding globulin (TBG) and transthyretin (TTR), in combination with a T4-coated biosensor chip were optimized and automated for screening chemical libraries. The transport protein-based biosensor assays were rapid, high throughput and bioeffect-related. A library of 62 chemicals including the natural hormones, polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and metabolites, halogenated bisphenol A (BPA), halogenated phenols, pharmaceuticals, pesticides and other potential environmentally relevant chemicals was tested with the two assays. We discovered ten new active compounds with moderate to high affinity for TBG with the TBG assay. Strikingly, the most potent binding was observed with hydroxylated metabolites of the brominated diphenyl ethers (BDEs) BDE 47, BDE 49 and BDE 99, that are commonly found in human plasma. The TTR assay confirmed the activity of previously identified hydroxylated metabolites of PCBs and PBDEs, halogenated BPA and genistein. These results show that the hydroxylated metabolites of the ubiquitous PBDEs not only target the T4 transport at the TTR level, but also, and to a great extent, at the TBG level where most of the T4 in humans is circulating. The optimized SPR biosensor-based transport protein assay is a suitable method for high throughput screening of large libraries for potential thyroid hormone disrupting compounds

  8. Biosensor discovery of thyroxine transport disrupting chemicals.

    Science.gov (United States)

    Marchesini, Gerardo R; Meimaridou, Anastasia; Haasnoot, Willem; Meulenberg, Eline; Albertus, Faywell; Mizuguchi, Mineyuki; Takeuchi, Makoto; Irth, Hubertus; Murk, Albertinka J

    2008-10-01

    Ubiquitous chemicals may interfere with the thyroid system that is essential in the development and physiology of vertebrates. We applied a surface plasmon resonance (SPR) biosensor-based screening method for the fast screening of chemicals with thyroxine (T4) transport disrupting activity. Two inhibition assays using the main thyroid hormone transport proteins, T4 binding globulin (TBG) and transthyretin (TTR), in combination with a T4-coated biosensor chip were optimized and automated for screening chemical libraries. The transport protein-based biosensor assays were rapid, high throughput and bioeffect-related. A library of 62 chemicals including the natural hormones, polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and metabolites, halogenated bisphenol A (BPA), halogenated phenols, pharmaceuticals, pesticides and other potential environmentally relevant chemicals was tested with the two assays. We discovered ten new active compounds with moderate to high affinity for TBG with the TBG assay. Strikingly, the most potent binding was observed with hydroxylated metabolites of the brominated diphenyl ethers (BDEs) BDE 47, BDE 49 and BDE 99, that are commonly found in human plasma. The TTR assay confirmed the activity of previously identified hydroxylated metabolites of PCBs and PBDEs, halogenated BPA and genistein. These results show that the hydroxylated metabolites of the ubiquitous PBDEs not only target the T4 transport at the TTR level, but also, and to a great extent, at the TBG level where most of the T4 in humans is circulating. The optimized SPR biosensor-based transport protein assay is a suitable method for high throughput screening of large libraries for potential thyroid hormone disrupting compounds.

  9. Biosensor discovery of thyroxine transport disrupting chemicals

    NARCIS (Netherlands)

    Marchesini, G.R.; Meimaridou, A.; Haasnoot, W.; Meulenberg, E.; Albertus, F.; Mizuguchi, M.; Takeuchi, M.; Irth, H.; Murk, A.J.

    2008-01-01

    Ubiquitous chemicals may interfere with the thyroid system that is essential in the development and physiology of vertebrates. We applied a surface plasmon resonance (SPR) biosensor-based screening method for the fast screening of chemicals with thyroxine (T4) transport disrupting activity. Two

  10. Thyroid hormones in the elderly sick: "T4 euthyroidism".

    Science.gov (United States)

    Burrows, A W; Shakespear, R A; Hesch, R D; Cooper, E; Aickin, C M; Burke, C W

    1975-11-22

    Thyroid function and serum levels of triiodothyronine (T3) and thyroxine (T4) were investigated in 79 euthyroid geriatric patients. Of the 59 inpatients and 20 outpatients 35 (59%) and 2, respectively, had low T3 levels. In contrast, 7 (12%) and 6 (30%), respectively, had raised T4 levels. Two further patients were excluded from the study because of raised levels of thyroid-stimulating hormone. Thyroxine-binding globulin was greatly increased in both groups of patients, but low serum albumin levels were present in 31 (39%). Despite these changes free T3 and T4 indices closely followed total T3 and T4 levels. The difference between the two groups of patients did not correlate with body weight, diagnostic categories, age, drug treatment, or duration of stay in hospital.

  11. Thyroxine and thyrotropin radioimmunoassays using dried blood samples on filter paper for screening of neonatal hypothyroidism

    International Nuclear Information System (INIS)

    Beckers, C.; Cornette, C.; Francois, B.; Bouckaert, A.; Lechat, M.

    1977-01-01

    A routine and automatized methodology for thyroxine (T4) and thyrotropin (TSH) radioimmunoassay (RIA) using dried blood samples on filter paper is described. Five mm diameter dots were prepared. One eluted dot, corresponding to 4 μl of plasma, was used for T4-RIA while two were necessary for TSH-RIA. Reference filter papers were introduced in each assay for quality control. In a preliminary study on 1903 newborns, samples were obtained, generally between the 5th-7th day. Mean dot T4 was 7.38 +- 2.5 μg/dl. Mean dot TSH was 11.83 +- 9.1 μU/ml, the equation of the regression line between dot TSH (y) and serum TSH (x) being Y = 10.29 + 0.623x. (orig.) [de

  12. A genome-wide association study of thyroid stimulating hormone and free thyroxine in Danish children and adolescents

    DEFF Research Database (Denmark)

    Nielsen, Tenna Ruest Haarmark; Appel, Emil Vincent Rosenbaum; Svendstrup, Mathilde

    2017-01-01

    BackgroundHypothyroidism is associated with obesity, and thyroid hormones are involved in the regulation of body composition, including fat mass. Genome-wide association studies (GWAS) in adults have identified 19 and 6 loci associated with plasma concentrations of thyroid stimulating hormone (TSH......) and free thyroxine (fT4), respectively.ObjectiveThis study aimed to identify and characterize genetic variants associated with circulating TSH and fT4 in Danish children and adolescents and to examine whether these variants associate with obesity.MethodsGenome-wide association analyses of imputed genotype...... data with fasting plasma concentrations of TSH and fT4 from a population-based sample of Danish children, adolescents, and young adults, and a group of children, adolescents, and young adults with overweight and obesity were performed (N = 1,764, mean age = 12.0 years [range 2.5-24.7]). Replication...

  13. Evaluation of a new free-thyroxin assay

    International Nuclear Information System (INIS)

    Welby, M.L.; Guthrie, L.; Reilly, C.P.

    1981-01-01

    The Amerlex Free Thyroxin (T 4 ) Radioimmunoassay Kit (Amersham International Ltd.) is a new direct equilibrium radioimmunoassay for free T 4 based on an antiserum with very high affinity for T 4 , and a unique 125 l-labeled T 4 analog as tracer. It is a very simple single-tube radioimmunoassay, making use of Amerlex particles to separate antibody-bound from free species. Interassay precision (CV) is 3.7% at 13 pmol/L and 2.3% at 30 pmol/L; within-assay precision is 4.2% at 21 pmol/L. The reference interval is 11-22 pmol/L. The assay did not misclassify any patients tested who had untreated myxedema or untreated thyrotoxicosis. The free T 4 assay excelled both the free T 4 index and the T 4 /T 4 -binding globulin ratio in correcting for increased thyroxin-binding globulin from pregnancy, and it was better than the index but not better than the ratio in correcting for increased thyroxin-binding globulin in users of oral contraceptives

  14. The effect of phenobarbital on the metabolism and excretion of thyroxine in rats

    International Nuclear Information System (INIS)

    McClain, R.M.; Levin, A.A.; Posch, R.; Downing, J.C.

    1989-01-01

    The effect of phenobarbital on thyroid function and the metabolism and biliary excretion of thyroxine in rats was determined. Phenobarbital, administered for 2 weeks at a dose of 100 mg/kg/day, resulted in an increase in hepatic and thyroid gland weights, decreased circulating levels of T4, T3 and rT3, and increased TSH levels in male and female rats. After 3 months of treatment liver and thyroid weights were still increased; however, hormone values were not as markedly affected indicating that the rats had partially compensated for the effect on thyroid function. In thyroidectomized rats the plasma clearance of thyroxine was increased with phenobarbital. In bile duct cannulated phenobarbital-treated male rats the hepatic uptake at 4 hr was markedly increased. Bile flow was increased and the 4-hr cumulative biliary excretion of administered radioactivity was increased by 42%. Most of the increase in the excretion (76%) was accounted for by an increase in the excretion of thyroxine-glucuronide in phenobarbital-treated rats. Hepatic thyroxine-glucuronyltransferase activity in phenobarbital-treated rats expressed as picomoles per milligram of protein was increased by 40%; enzyme activity per gram of liver was increased by about twofold which, coupled with increased hepatic weight, resulted in about a threefold increase in total hepatic thyroxine-glucuronyltransferase activity in phenobarbital-treated rats as compared to that of controls. Qualitatively similar effects on metabolism, excretion, and enzyme induction were noted in female rats; however, the magnitude of increase was less than that observed in male rats. It is concluded that the effect of phenobarbital on thyroid function in rats is primarily a result of its effects on the hepatic disposition of thyroid hormone

  15. Effect of intravenous injection of galanin on plasma concentrations ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-06

    Oct 6, 2008 ... The goal of this study was to determine whether intravenously galanin injection effect on plasma concentrations of growth hormone (GH), thyroxine (T4), triiodothyronine (T3) and milk production in the. Saanen goats. Fifteen Saanen goats were randomly divided into 5 groups (n = 3 in each group). Each.

  16. In vitro fluorescence displacement investigation of thyroxine transport disruption by bisphenol A

    Institute of Scientific and Technical Information of China (English)

    Jie Cao; Liang-Hong Guo; Bin Wan; Yin Wei

    2011-01-01

    Bisphenol A (BPA) is a chemical with high production volume and wide applications in many industries.Although BPA is known as an endocrine disruptor, its toxic mechanisms have not been fully characterized.Due to its structural similarity to thyroid hormones thyroxine (T4) and triiodothyronine (T3), one possible mechanism of BPA toxicity is disruption of hormone transport by competitive binding with the transport proteins.In this study, the binding interactions of BPA, T4, and T3 with three thyroid hormone transport proteins, human serum albumin (HSA), transthyretin (TTR), and thyroxine-binding globulin (TBG) were investigated by fluorescence measurement.Using two site-specific fluorescence probes dansylamide and dansyl-L-proline, the binding constants of BPA with HSA at drug site I and site Ⅱ were determined as 2.90 × 104 and 3.14 × 104 L/mol, respectively.By monitoring the intrinsic fluorescence of tryptophan, a binding constant of 4.70 × 103 L/mol was obtained.Similarly, by employing 8-anilino-1-naphthalenesulfonic acid as fluorescence probe, the binding affinity of BPA with TTR and TBG was measured to be 3.10 × 105 and 5.90 × 105 L/mol, respectively.In general, BPA showed lower binding affinity with the proteins than T3 did, and even lower affinity than T4.Using these binding constants, the amount of BPA which would bind to the transport proteins in human plasma was estimated.These results suggest that the concentrations of BPA commonly found in human plasma are probably not high enough to interfere with T4 transport.

  17. Prolactin, cortisol and thyroxine levels and the premature infant

    African Journals Online (AJOL)

    1983-04-16

    Apr 16, 1983 ... and the premature infant ... values in cord and maternal plasma to fetal age and weight and to the incidence of hyaline membrane disease (HMD) was .... thyroxine and prolactin values with an increase in weight has also.

  18. t4 Workshop Report

    Science.gov (United States)

    Silbergeld, Ellen K.; Contreras, Elizabeth Q.; Hartung, Thomas; Hirsch, Cordula; Hogberg, Helena; Jachak, Ashish C.; Jordan, William; Landsiedel, Robert; Morris, Jeffery; Patri, Anil; Pounds, Joel G.; de Vizcaya Ruiz, Andrea; Shvedova, Anna; Tanguay, Robert; Tatarazako, Norihasa; van Vliet, Erwin; Walker, Nigel J.; Wiesner, Mark; Wilcox, Neil; Zurlo, Joanne

    2014-01-01

    Summary In October 2010, a group of experts met as part of the transatlantic think tank for toxicology (t4) to exchange ideas about the current status and future of safety testing of nanomaterials. At present, there is no widely accepted path forward to assure appropriate and effective hazard identification for engineered nanomaterials. The group discussed needs for characterization of nanomaterials and identified testing protocols that incorporate the use of innovative alternative whole models such as zebrafish or C. elegans, as well as in vitro or alternative methods to examine specific functional pathways and modes of action. The group proposed elements of a potential testing scheme for nanomaterials that works towards an integrated testing strategy, incorporating the goals of the NRC report Toxicity Testing in the 21st Century: A Vision and a Strategy by focusing on pathways of toxic response, and utilizing an evidence-based strategy for developing the knowledge base for safety assessment. Finally, the group recommended that a reliable, open, curated database be developed that interfaces with existing databases to enable sharing of information. PMID:21993959

  19. Solid Phase Radioimmunoassay for Measuring Serum Triiodothyronine and Thyroxine using Different Preparations of Their Labeled Hormones

    International Nuclear Information System (INIS)

    El Kolaly, M.T; Mehany, N.L; Ayyoub, S.M.; Hassan, S.E.M.

    2005-01-01

    The goal of the present work was oriented to prepare stable polystyrene coated tubes for direct radioimmunoassay (RIA) of triiodothyronine (T 3 ) and thyroxine (T 4 ) in human serum or plasma. Coating process was performed using sheep polyclonal antisera specific for each of T 3 and T 4 . The stability study showed that these tubes could be stored for up to one year at 4 degree without any appreciable reduction in their binding. The preparations of 25 I-T 3 and 125 I-T 4 were carried out by two different methods [chloramine-T(Ch-T) and iodogen] . It was found that Ch-T method gave approximately the same results as iodogen method. Twenty five samples of different thyroid status were assayed for T 3 and T 4 using the present systems and with commerically available kits (coated tubes, DPC). The statistical analysis revealed good correlations between the results from the present systems using T 3 and T 4 tracers prepared by Ch-T and iodogen methods and The DPC kits. This may be extremely helpful in diagnosis and proper management of thyroid dysfunctions

  20. Thyroxin hormone suppression treatment

    International Nuclear Information System (INIS)

    Samuel, A.M.

    1999-01-01

    One of the important modalities of treatment of thyroid cancer (TC) after surgery is the administration of thyroxin as an adjuvant treatment. The analysis supports the theory that thyroid suppression plays an important role in patient management. 300 μg of thyroxin, as this is an adequate dose for suppression is given. Ideally the dose should be tailored by testing s-TSH levels. However, since a large number of the patients come from out station cities and villages this is impractical. We therefore depend on clinical criteria of hyperthyroid symptoms and adjust the dose. Very few patients need such adjustment

  1. Basal levels of triiodotironine, thyroxine, thyrotropin, free thyroxine and reverse triiodotyronine in patients with chronic renal failure submitted to hemodialysis

    International Nuclear Information System (INIS)

    Knobel, H.; Mendonca, B.B. de; Mendes, V.; Rocha Junior, J.E.; Medeiros Neto, G.

    1987-01-01

    Serum triiodotironine (T3), thyroxine (T4), thyrotropin (TSH), free thyroxine (FT4) and reverse triiodothyronine (rT3) concentrations were determined by radioimmunoassay in 21 uremic patients on regular hemodialysis therapy (sera were collected immediately before dialysis) and 11 normal controls. In advanced chronic renal failure serum T3 and T4 were frequently decreased (86% and 57%, respectively). and serum rT3 was normal (81%) or subnormal (14%). The serum TSH and FT4 values were normal in all cases even when serum T3 and T4 concentrations were decreased below the normal range. The findings suggest that the measurement of serum TSH probably represents the most reliable differentiation between this disease with low T4 levels and primary hypothyroidism. (author)

  2. Radioimmunoassay method for triiodothyronine and thyroxine

    International Nuclear Information System (INIS)

    Hollander, C.S.

    1975-01-01

    This invention relates to a radioimmunoassay method for triiodothyronine or thyroxine or triiodothyronine and thyroxine present in unextracted serum containing thyroxine binding prealbumin and thyroxine binding globulin. Procedures using 125 I and 131 I are described

  3. Reference interval of thyroxine and thyrotropin of healthyterm ...

    African Journals Online (AJOL)

    Objective: To establish a local Reference Interval of Serum Thyroxine (T4) and Serum Thyroid stimulating Hormone(TSH) of healthy Nigerian Newborns in Jos University Teaching Hospital Jos. Materials and Methods: One hundred and sixty healthy term Nigerian Newborns who fulfilled the criteria for inclusion were ...

  4. A solid-phase-radioimmunoassay for total serum thyroxine

    International Nuclear Information System (INIS)

    Moedder, G.; Sokolowski, G.

    1978-01-01

    A new solid phase radioimmunoassay for total serum thyroxine was evaluated over a longer time under clinical routine conditions and compared with an established test system. The results show up that the T 4 values are precise, reliable and reproducible, the is incomplicate to handle and well suitable for semiautomatic pipetting systems. (orig.) 891 MG [de

  5. Triiodothyronine and thyroxine content of desiccated thyroid tablets.

    Science.gov (United States)

    Rees-Jones, R W; Larsen, P R

    1977-11-01

    Triiodothyronine (T3) and thyroxine (T4) were measured by radioimmunoassay in Pronase hydrolysates of four lots each of 1- and 2-grain tablets of desiccated thyroid (Thyroid, Armour) and thyroglobulin (Proloid, Warner-Chilcott). The methodology used was verified by studies of tablets containing known quantities of T4 and T3. One grain of desiccated thyroid contained 12 +/- 1 and 64 +/- 3 microgram (mean +/- SD) of T3 and T4 per tablet, respectively (T4/T3 molar ratio, 4.3). A 1-grain tablet of thyroglobulin contained 16 +/- 2 and 55 +/- 5 microgram of T3 and T4, respectively with a T4/T3 ratio of 2.9. Two-grain tablets generally contained twice the quantity of T3 and T4 in the 1-grain preparations. The variation in T3 and T4 content between the four lots of each tablet strength for each product was 10% or less. These estimates of T3 and T4 content are 1.5- to 2-fold greater than those previously published. This difference probably results from the more sophisticated methodology now available which does not require chromatographic separation of T3 and T4 or iodometry. Using calculations based on published estimates of T4 and T3 absorption and of the T3/T4 potency ratio, it would appear that the T3 content of desiccated thyroid and thyroglobulin provide approximately 39% and 51%, respectively, of the thyromimetic activity of these two medications.

  6. Liquid L-thyroxine versus tablet L-thyroxine in patients on L- thyroxine replacement or suppressive therapy: a meta-analysis.

    Science.gov (United States)

    Laurent, Irakoze; Tang, Siying; Astère, Manirakiza; Wang, Kan Ran; Deng, Shuhua; Xiao, Ling; Li, Qi Fu

    2018-03-23

    To compare the effectiveness of liquid L-T4 (L-thyroxine) and tablet L-T4 in patients on L-T4 replacement or suppressive therapy. The Cochrane Library, PubMed, Embase, and Web of Science databases were searched to identify relevant articles. All prospective or randomized controlled studies (RCTs) comparing liquid L-T4 and tablet L-T4 in patients on L-T4 replacement or suppressive therapy were included in the analysis. Overall, the initial search of the four databases identified 1278 published studies; of these, eight studies were ultimately included in the meta-analysis. TSH (thyroid stimulating hormone) levels were significantly suppressed in patients on liquid L-T4 compared with those on tablet L-T4, in patients on L-T4 suppressive therapy with L-T4 malabsorption (Mean Difference (MD) = -2.26, 95% Confidence Interval (CI): -3.59, -0.93; P = 0.0009)). However, liquid L-T4 and tablet L-T4 did not show a statistically significant difference in patients on L-T4 suppressive therapy without malabsorption (MD = 0.08, 95% CI: -0.31, 0.47; P = 0.69). TSH levels were significantly normalized in patients on liquid L-T4 compared with those on tablet L-T4, in Patients on L-T4 replacement therapy with L-T4 malabsorption (MD = -3.20, 95% CI: -5.08, -1.32; P = 0.0009). However, liquid L-T4 and tablet L-T4 did not show a statistically significant difference in patients on L-T4 replacement therapy without malabsorption (MD = 0.91, 95% CI: -0.03, 1.86; P = 0.06). Liquid L-T4 is more efficient than tablet L-T4 in patients on L-T4 replacement or suppressive therapy with malabsorption. No significant differences were observed in patients without malabsorption. Further studies should be conducted to verify these findings.

  7. Cathepsin C and plasma glutamate carboxypeptidase secreted from Fischer rat thyroid cells liberate thyroxin from the N-terminus of thyroglobulin.

    Science.gov (United States)

    Suban, Dejan; Zajc, Tajana; Renko, Miha; Turk, Boris; Turk, Vito; Dolenc, Iztok

    2012-03-01

    The release of a thyroid hormone from thyroglobulin is controlled by a complex regulatory system. We focused on the extracellular action of two lysosomal enzymes, cathepsin C (catC, dipeptidyl peptidase I) and PGCP (lysosomal dipeptidase), on thyroglobulin, and their ability to liberate the hormone thyroxin. Cathepsin C, an exopeptidase, removes dipeptides from the N-terminus of substrates, and PGCP hydrolyses dipeptides to amino acids. In vitro experiments proved that cathepsin C removes up to 12 amino acids from the N-terminus of porcine thyroglobulin, including a dipeptide with thyroxin on position 5. The newly formed N-terminus, Arg-Pro-, was not hydrolysed further by cathepsin C. Cell culture experiments with FRTL-5 cell line showed localization of cathepsin C and PGCP and their secretion into the medium. Secretion of the active cathepsin C from FRTL-5 cells is stimulated by TSH, insulin, and/or somatostatin. The released enzymes liberate thyroxin from porcine thyroglobulin added to media. The hormone liberation can be reduced by synthetic inhibitors of cysteine proteinases and metalloproteinases. Additionally, we show that TSH, insulin, and/or somatostatin induce up-regulation of N-acetylglucosaminyltransferase 1, the enzyme responsible for the initiation of biosynthesis of hybrid and complex N-glycosylation of proteins. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  8. Preparation and separation of the glucuronide and sulfate conjugates of thyroxine and triiodothyronine

    International Nuclear Information System (INIS)

    Hays, M.T.; Hsu, L.

    1987-01-01

    An enzymatic method for synthesis of labelled thyroxine glucuronide (T4G) and triiodothyronine glucuronide (T3G) from labelled thyroxine (T4) and triiodothyronine (T3) is presented. The synthetic glucuronides are completely digested by beta-glucuronidase, with recovery of the parent T4 or T3. They have distinctive elution patterns on HPLC and on Sephadex G25 chromatography, and can be clearly separated from T4 and T3 as well as from synthetic T4 sulfate (T4S) and T3 sulfate (T3S). On LH 20 chromatography, elution of T4G and T3G is intermediate between that of T4 and T3 and that of T4S and T3S. T3G can be well separated from other thyronines by HPLC alone, but T4G coelutes with rT3 on HPLC; these are then separated by adding a Sephadex G25 chromatography step. Biosynthetic 131 I-T3G and 125 I-T4G from the bile of a cat given 131 I-T3 and 125 I-T4 had similar HPLC chromatographic patterns to those of synthetic T3G and T4G. That the identified peaks from analysis of the bile were indeed T3G and T4G was confirmed by recovery of the parent T3 and T4 after beta-glucuronidase digestion

  9. Effects of shugan jieyu panacea on behavior and levels of ACTH in plasma and T3, T4, TSH and rT3 in serum in depression rats

    International Nuclear Information System (INIS)

    Li Huijing; Li Yang; Yao Jinghui; Li Youtian

    2010-01-01

    Objective: To investigate the effects of Shugan Jieyu Panacea (SJP) on behavior and the levels of ACTH in plasma and T 3 , T 4 , TSH, rT 3 in serum in depression model rats and explore the mechanism. Methods: The model rats were lonely fed and received chronic moderate intensive unpredictable stimulation. Normal control group, depressed model group, high dosage SJP group, middle dosage SJP group, low dosage SJP group and fluoxetine group were set up. Different drugs were used in various groups for 21 d, then the body mass, sugar consumption and the behavior changes of the rats were determined and the levels of ACTH in plasma and T 3 , T 4 , TSH, rT 3 in serum were detected with radioimmunoassay. Results: Compared with normal group,the body mass was decreased (P 4 , rT 3 markedly decreased (P 3 was increased (P<0.05) in high, middle, low dosage SJP groups after treatment. At the same time, there was no obvious difference between SJP groups and fluoxetine groups. Conclusion: SJP can significantly improve the depression in rats, its mechanism may be connected with adjusting the function of HPAA and HPTA. (authors)

  10. 2012 ETA Guidelines: The Use of L-T4 + L-T3 in the Treatment of Hypothyroidism

    DEFF Research Database (Denmark)

    Nygaard, Birte

    2012-01-01

    . Results: Suggested explanations for persisting symptoms include: awareness of a chronic disease, presence of associated autoimmune diseases, thyroid autoimmunity per se, and inadequacy of L-T4 treatment to restore physiological thyroxine (T4) and triiodothyronine (T3) concentrations in serum and tissues...

  11. Triiodothyronine and thyroxine in urine. I. Measurement and application.

    Science.gov (United States)

    Shakespear, R A; Burke, C W

    1976-03-01

    Urinary triiodothyronine (T3) and thyroxine (T4) were measured by RIA, and T4 was also measured by competitive protein binding (CPB). pH 1-hydrolysable conjugates were 48% of total urinary T3, and enzyme- or pH 1-hydrolysable conjugates were 55% and 61% of total urinary T4. The mean unconjugated T3 excretion was 34.3 ng/h (0.99 mug T3/g creatinine) in normal subjects (no day-night rhythm found), 1.56 mug/g in late pregnancy, 0.82 mug/g in neonates (1-12 days), and was also unchanged in persons with high or low thyroxine-binding globulin (TBG). In thyrotoxicosis, mean T3 excretion was 281 ng/h, no values being in the normal range. In primary hypothyroidism it was 18.3 ng/h, but over half the values were in the normal range. The mean urinary unconjugated T4 was 82.2 ng/h (1.37 mug T4/g creatinine) in normal subjects, 1.6 mug/g in neonates, and unchanged in persons with high or low TBG, except that in pregnancy high values were compatible with increases protein excretion. Apparently increased day-time T4 excretion compared with night-time excretion may also be due to changes in protein excretion rate. The mean T4 in thyrotoxicosis was 337 ng/h (12% of values in the normal range) and 32.8 ng/h in primary hypothyroidism (over half the normal range). All the assays, especially that of T4 by CPB gave readings which were incorrect with protein concentrations above 100 mg/l. Urinary T3 and T4 assays for clinical purposes have few practical advantages over serum assays, despite the relationship of urine T3 and T4 to serum unbound levels.

  12. Thyroxine and triiodothyronine kinetics in aging subjects

    International Nuclear Information System (INIS)

    Degrossi, O.J.; Carneiro, L.; Scornavachi, J.C.; Cima, M.E.; Mollerach, F.E.; Almeida, C.A.; Casas, O.I. de; Diez, F.

    1980-06-01

    Age modifications on serum levels of thyrotropin hormone (TSH) thyroxine (T4) and Triiodothyronine (T3), as well the kinetics of T4 and T3 were studied. T4 serum values were found to be in the normal range. T3 rates showed a significant decrease as TSH showed a slight increase, which was only significantin patients over 70 year-old. Metabolic T4 turnover allowed to observe a slower T4 disappearance rate with dialy degradation values of 35,4 μg/day/m 2 +-14,1 (S.D.)as compared with those of the control subjects (49,0+-14,6): Distribution space was in the normal range. On the contrary, for T3 a sharp decrease in distribution space (31,1% body weight+-3,5; controls 58,8%+-7,6), a slight lengthening in disappearance rate and a marked shortening of the clearance (17,32 l/d+-6,20; controls 33,72+-8.55), of T3 extrathyroid pool (14,5 μg+-1,8; controls 45,7+-4.7) and of the daily degradation rate (4,3 μg/d/m 2 +-1,7; controls: 15,3+-2,6) were observed. These results conveys to considere a diminished thyroid hormones production and of an also diminished peripheric conversion of T4 to T3. It should be delucidated if there is a real inadequate thyroid hormones suply to the tissues or if there is only an adaptation, to lower demands due to a diminished functional mass [es

  13. Thyroxine transport in choroid plexus

    International Nuclear Information System (INIS)

    Dickson, P.W.; Aldred, A.R.; Menting, J.G.; Marley, P.D.; Sawyer, W.H.; Schreiber, G.

    1987-01-01

    The role of the choroid plexus in thyroid hormone transport between body and brain, suggested by strong synthesis and secretion of transthyretin in this tissue, was investigated in in vitro and in vivo systems. Rat choroid plexus pieces incubated in vitro were found to accumulate thyroid hormones from surrounding medium in a non-saturable process. At equilibrium, the ratio of thyroid hormone concentration in choroid plexus pieces to that in medium decreased upon increasing the concentration of transthyretin in the medium. Fluorescence quenching of fluorophores located at different depths in liposome membranes showed maximal hormone accumulation in the middle of the phospholipid bilayer. Partition coefficients of thyroxine and triiodothyronine between lipid and aqueous phase were about 20,000. After intravenous injection of 125 I-labeled thyroid hormones, choroid plexus and parts of the brain steadily accumulated 125 I-thyroxine, but not [ 125 I]triiodothyronine, for many hours. The accumulation of 125 I-thyroxine in choroid plexus preceded that in brain. The amount of 125 I-thyroxine in non-brain tissues and the [ 125 I]triiodothyronine content of all tissues decreased steadily beginning immediately after injection. A model is proposed for thyroxine transport from the bloodstream into cerebrospinal fluid based on partitioning of thyroxine between choroid plexus and surrounding fluids and binding of thyroxine to transthyretin newly synthesized and secreted by choroid plexus

  14. Corticosterone and thyroxine in cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii).

    Science.gov (United States)

    Hunt, Kathleen E; Innis, Charles; Rolland, Rosalind M

    2012-09-01

    Kemp's ridley sea turtles (Lepidochelys kempii), a critically endangered species, frequently strand on the shores of Cape Cod (Massachusetts, USA) in late autumn in a state of "cold-stunning" exhibiting low body temperature and related clinical issues. Stranded turtles are transported to the New England Aquarium (Boston, Massachusetts, USA) for treatment and rehabilitation. This study tested the hypothesis that cold-stunned sea turtles might exhibit high corticosterone ("stress hormone") or low thyroxine (which is often affected by temperature), or both, and that monitoring of both hormones may be useful for assessing recovery. In a retrospective analysis, 87 archived plasma samples were assayed from 56 cold-stunned juvenile Kemp's ridley sea turtles for corticosterone and free thyroxine (fT4). Upon admission, mean corticosterone was the highest yet reported for a population of sea turtles (39.3 +/- 2.5 ng/ml; mean +/- standard error of the mean [SEM]) and fT4 was usually undetectable. On admission, corticosterone was negatively correlated with white blood cell count but was not correlated with blood glucose. There were no differences in either hormone between survivors and nonsurvivors on admission. After 18+ days in recovery, surviving turtles' corticosterone dropped significantly to levels typical of baseline in other species (0.9 +/- 1.0 ng/ml) while fT4 increased significantly (1.3 +/- 1.5 pg/ml). During recovery, corticosterone was positively correlated with blood glucose and was not correlated with white blood cell count. Turtles that showed persistent deficits in feeding, activity, or both during recovery had significantly lower fT4 than did turtles with no such deficits. The "high corticosterone, low fT4" endocrine profile seen on admission may be a useful marker of cold-stunning in this and other species. Further studies are necessary to determine whether low thyroid hormones play a causal role in deficits in feeding and activity during recovery

  15. Importance of the content and localization of tyrosine residues for thyroxine formation within the N-terminal part of human thyroglobulin

    NARCIS (Netherlands)

    den Hartog, M. T.; Sijmons, C. C.; Bakker, O.; Ris-Stalpers, C.; de Vijlder, J. J.

    1995-01-01

    Thyroxine (T4) is formed by coupling of iodinated tyrosine residues within thyroglobulin (TG). In mature TG, some iodinated tyrosine residues are involved preferentially in T4 formation. In order to investigate the specific role of various tyrosine residues in T4 formation, N-terminal TG fragments

  16. Prolactin, cortisol and thyroxine levels and the premature infant ...

    African Journals Online (AJOL)

    The relationship of prolactin, cortisol and thyroxine values in cord and maternal plasma to fetal age and weight and to the incidence of hyaline membrane disease (HMD) was investigated in 80 neonates of whom 40 were born at more than 37 weeks' gestation. Of the 40 born at less than 36 weeks 11 developed HMD.

  17. Basic and clinical evaluation of thyroxine radioimmunoassay kit. I. T-4 RIA kit

    Energy Technology Data Exchange (ETDEWEB)

    Bunko, H; Hisada, K [Kanazawa Univ. (Japan). Hospital

    1976-02-01

    The T/sub 4/ RIA kit is based on single antibody radioimmunoassay and utilizes a resin-sponge to separate free T/sub 4/-/sup 125/I from the incubation mixture. The use of the sodium salt of trichloroacetic acid (TBG inhibitor) permits direct radioimmunoassay of T/sub 4/ without a tedious extraction procedure. The T/sub 4/ RIA kit needs only 0.05 ml of patient serum and one hour of incubation to measure T/sub 4/. The TBG inhibitior was equivalent to 5.1 ..mu..g% of T/sub 4/ in displacing radioactive T/sub 4/ from TBG in a CPBA(Res-O-Mat T/sub 4/) system, and the TBG inhibitor volume of 0.5 ml (ten times of serum) was needed to measure a high T/sub 4/ concentration serum. The change of incubation temperature was more affected on the standard curve than that of incubation time. Correlation of the T/sub 4/ value between radioimmunoassay and CPBA in 69 patients was good (r=0.88612, p<0.01) and showed a slightly higher T/sub 4/ value when measured with radioimmunoassay than CPBA (linear regression function: Y=1.17506 + 0.95766X). Correlation of T/sub 4/ between Compu-curve and conventional standard curve was excellent (r=0.9995), but a slight difference was found in both low and high T/sub 4/ concentrations. In euthyroid patients without thyroid diseases, T/sub 4/ concentration was 9.92 +- 2.66 (SD) ..mu..g% and the normal range was between 4.60 and 15.24 ..mu..g%. Reproducibility within assay was 9.9% (CV) and recovery rate was 70% when added 10 ..mu..g of T/sub 4/ and 86% when added 15 ..mu..g% of T/sub 4/. From these results, the authors concluded that radioimmunoassay of serum T/sub 4/ using the T/sub 4/ RIA kit would be a promising one, especially when measuring a large amount of samples per assays.

  18. A genome-wide association study of thyroid stimulating hormone and free thyroxine in Danish children and adolescents.

    Directory of Open Access Journals (Sweden)

    Tenna Ruest Haarmark Nielsen

    Full Text Available Hypothyroidism is associated with obesity, and thyroid hormones are involved in the regulation of body composition, including fat mass. Genome-wide association studies (GWAS in adults have identified 19 and 6 loci associated with plasma concentrations of thyroid stimulating hormone (TSH and free thyroxine (fT4, respectively.This study aimed to identify and characterize genetic variants associated with circulating TSH and fT4 in Danish children and adolescents and to examine whether these variants associate with obesity.Genome-wide association analyses of imputed genotype data with fasting plasma concentrations of TSH and fT4 from a population-based sample of Danish children, adolescents, and young adults, and a group of children, adolescents, and young adults with overweight and obesity were performed (N = 1,764, mean age = 12.0 years [range 2.5-24.7]. Replication was performed in additional comparable samples (N = 2,097, mean age = 11.8 years [1.2-22.8]. Meta-analyses, using linear additive fixed-effect models, were performed on the results of the discovery and replication analyses.No novel loci associated with TSH or fT4 were identified. Four loci previously associated with TSH in adults were confirmed in this study population (PDE10A (rs2983511: β = 0.112SD, p = 4.8 ∙ 10-16, FOXE1 (rs7847663: β = 0.223SD, p = 1.5 ∙ 10-20, NR3C2 (rs9968300: β = 0.194SD, p = 2.4 ∙ 10-11, VEGFA (rs2396083: β = 0.088SD, p = 2.2 ∙ 10-10. Effect sizes of variants known to associate with TSH or fT4 in adults showed a similar direction of effect in our cohort of children and adolescents, 11 of which were associated with TSH or fT4 in our study (p<0.0002. None of the TSH or fT4 associated SNPs were associated with obesity in our cohort, indicating no pleiotropic effects of these variants on obesity.In a group of Danish children and adolescents, four loci previously associated with plasma TSH concentrations in adults, were associated with plasma TSH

  19. Rapid purification of tri-iodothyronine and thyroxine protein conjugates for antibody production.

    Science.gov (United States)

    Burke, C W; Shakespear, R A

    1975-04-01

    Thyroxine (T-4) and tri-iodothyronine (T-3) were coupled to human serum albumin (HSA) with carbodi-imide. By adsorption chromatography on Sephadex G-25, fractions containing purified conjugate, but not reversibly-bound T-3 or T-4, were obtained, and this procedure took 5 h; considerably less than the conventional dialysis technique. Highly specific high-titre antisera were produced in rabbits and guinea-pigs by injection of these fractions in Freund's adjuvant.

  20. The concentration of iodine in horse serum and its relationship with thyroxin concentration by geological difference.

    Science.gov (United States)

    Mochizuki, Mariko; Hayakawa, Noriyuki; Minowa, Fumiko; Saito, Akihiro; Ishioka, Katsumi; Ueda, Fukiko; Okubo, Kimihiro; Tazaki, Hiroyuki

    2016-04-01

    In this study, iodine and thyroxin (T4) concentrations in the serum of 69 horses were investigated. Higher iodine concentrations were obtained from the horses housed in Chiba Prefecture. In contrast, T4 concentrations of horses at Shizuoka Prefecture were higher than those of horses at Chiba Prefecture. There was a significant correlation (r = 0.643, P geological differences. It was thought that equine serum is a useful sample for monitoring.

  1. Serum TBG and T4 concentration in non-thyroidal diseases

    International Nuclear Information System (INIS)

    Sasaki, Y.; Tobari, C.; Sekita, N.; Onodera, Y.; Asazu, M.; Someya, K.

    1983-01-01

    Routinely available radioassay kits have recently enabled the measurement of serum concentrations of thyroxine binding globulin (TBG) and thyroxine (T 4 ), both total (TT 4 ) and free (FT 4 ) in various disease conditions. Serum TBG and T 4 level were measured in variety of non-thyroidal diseases, of which significance was evaluated in comparison with that in thyroidal diseases. Abnormal serum TBG concentrations in various non-thyroidal diseases and pregnancy result in abnormal serum TT 4 levels, which may cause difficulty in differentiation of these conditions from hyper- or hypothyroidal states. Serum FT 4 levels give better indicator than TT 4 , though the difference among RIA kits are considerably large. However, measurement of serum FT 4 levels alone is not sufficient to distinguish non-thyroidal disease from thyroidal diseases with abnormal thyroidal function. The differentiation has to be based on the combination of clinical findings and results of multiple thyroidal function tests

  2. Diagnostic Evaluation of Effective Thyroxine Ratio

    International Nuclear Information System (INIS)

    Lee, Myung Chul; Choi, Sang Jae; Ro, Heung Kyu; Lee, Hong Kyu; Koh, Chang Soon; Lee, Mun Ho

    1975-01-01

    The purpose of the present study is to evaluate the diagnostic value of the ETR test as compared to other thyroid function tests in normal persons, patients with thyroid disorders and patients with alterations of thyroxine-binding proteins. The ETR values were obtained from 35 cases as normal control, 63 hyperthyroid patients, 56 euthyroid patients, 23 hypothyroid patients, 10 pregnant women, 5 women taking oral contraceptive medication, 8 liver cirrhosis patients and 4 nephrotic syndrome patients. The results obtained were as follows. 1) The mean value of ETR obtained from the normal controls was 0.99±0.06. 2) The mean ETR values of various thyroid states were 1.25±0.16 in hyperthyroidism, 0.99±0.08 in euthyroidism and 0.82±0.05 in hypothyroidism and significant difference was found between these groups. 3) Seven out of 63 hyperthyroid patients (11.1%) and 2 out of 23 hypothyroid patients (8.7%) had ETR values within normal range and among the 56 euthyroid patients 6 (10.7%) had ETR values outside normal range, so the diagnostic compatibility of ETR was 89.4% in thyroid diseases. 4) Even though the ETR value was well correlated with 131 I-thyroid uptake rate, serum T 3 resin uptake rate and serum T 4 , a high positive correlation was found (r=0.79) between ETR and T 7 . 5) The mean ETR values from patients with alteration in TBG binding capacity were 0.99±0.05 in pregnant women, 0.98±0.04 in women with oral contraceptive medication, 1.04±0.09 in liver cirrhosis patients and 0.94±0.02 in nephrotic syndrome patients and most of them (85.2%) had ETR values within normal range. Our results, therefore, suggests that the ETR estimation does offer the simplest and most reliable single procedure for the screening and diagnosis of various thyroid diseases as a indirect indicator of serum-free thyroxine concentration without essential influence of changes in the thyroxine-binding proteins in serum.

  3. Triclosan exposure reduces thyroxine levels in pregnant and lactating rat dams and in directly exposed offspring

    DEFF Research Database (Denmark)

    Petersen, Marta Axelstad; Boberg, Julie; Vinggaard, Anne Marie

    2013-01-01

    Thyroid disrupting chemicals can potentially disrupt brain development. Two studies investigating the effect of the antibacterial compound triclosan on thyroxine (T4) levels in rats are reported. In the first, Wistar rat dams were gavaged with 75, 150 or 300 mg triclosan/kg bw/day throughout gest...

  4. Propranolol inhibits the in vitro conversion of thyroxine into triiodothyronine by isolated rat liver parenchymal cells

    NARCIS (Netherlands)

    van Noorden, C. J.; Wiersinga, W. M.; Touber, J. L.

    1979-01-01

    A model for the in vitro study of the conversion of thyroxine into triiodothyronine using isolated rat liver parenchymal cells is described. Isolated liver cells (mean protein content 18 mg/ml) convert approximately 0.8% of 1.3 microM exogenously added T4 into T3 during thirty minutes incubation.

  5. High free thyroxine levels are associated with QTc prolongation in males

    NARCIS (Netherlands)

    C. van Noord (Charlotte); W.M. van der Deure (Wendy); M.C.J.M. Sturkenboom (Miriam); S.M.J.M. Straus (Sabine); A. Hofman (Albert); T.J. Visser (Theo); J.A. Kors (Jan); J.C.M. Witteman (Jacqueline); B.H.Ch. Stricker (Bruno)

    2008-01-01

    textabstractThe literature on the effect of excess thyroid hormone on ventricular repolarization is controversial. To study whether free thyroxine (T4) and TSH are associated with QTc prolongation we conducted population-based cohort study. This study was conducted as part of the Rotterdam Study and

  6. Preparation of quality control samples for thyroid hormones T3 and T4 in radioimmunoassay techniques

    International Nuclear Information System (INIS)

    Ahmed, F.O.A.

    2006-03-01

    Today, the radioimmunoassay becomes one of the best techniques for quantitative analysis of very low concentration of different substances. RIA is being widely used in medical and research laboratories. To maintain high specificity and accuracy in RIA and other related techniques the quality controls must be introduced. In this dissertation quality control samples for thyroid hormones (Triiodothyronine T3 and Thyroxin T4), using RIA techniques. Ready made chinese T4, T3 RIA kits were used. IAEA statistical package were selected.(Author)

  7. 216-T-4 interim stabilization final report

    International Nuclear Information System (INIS)

    Smith, D.L.

    1996-01-01

    This report provides a general description of the activities performed for the interim stabilization of the 216-T-4-1 ditch, 216-T-4-2 ditch, and 216-T-4-2 pond. Interim stabilization was required to reduce the amount of surface-contaminated acres and to minimize the migration of radioactive contamination. Work associated with the 216-T4-1 ditch and 216-T-4-2 pond was performed by the Radiation Area Remedial Action (RARA) Project. Work associated with the 216-T-4-2 ditch was done concurrently but was funded by Westinghouse Hanford Company (WHC) Tank Waste Remediation Systems (TWRS)

  8. Competitive protein binding analysis for thyroxine using Sephadex column (Tetralute)

    International Nuclear Information System (INIS)

    Miyai, Kiyoshi; Katayama, Yoshiaki; Sawazaki, Norio; Ishibashi, Kaichiro; Kawashima, Minoru.

    1975-01-01

    The method of competitive protein binding analysis of thyroxine (T 4 ) using Tetralute kit was evaluated. The net retention was decreased when the procedure of competition and separation was performed at a higher temperature but the final T 4 -I values were constant when the standard and test sera were treated identically. Coefficient of variation (C.V.) was 4% (within-assay) and 6% (between-assay) respectively. However, the T 4 -I values of pooled serum for quality control were slightly lower in earlier experiments in which correction factors (1.03--1.62 in 18 out of 21 assays) were necessary. T 4 -I values were determined by the Tetralute in 155 cases. They were as follows: 4.9+-0.8 μg/dl (euthyroid subjects), 6.4+-1.2 μg/dl (cord serum), 7.1+-1.1 μg/dl (pregnant women). 9.0+-3.6 μg/dl (trophoblastic disease), 13.3+-4.8 μg/dl (Graves' disease), 6.3+-1.6 μg/dl (Plummer's disease), 4 -I values determined by Tetralute and Res-O-Mat T 4 (r=0.96). Following oral administration of Telepaque the serum protein-bound iodine was markedly elevated, while the T 4 -I determined by Tetralute did not change. In vitro addition of diphenylhydantoin (500 μg/ml), salicylate (4 mg/ml) and phenobarbital (1 mg/ml) had no or little effect on T 4 determination by Tetralute. A high concentration of benzbromarone (0.1 mg/ml) caused a higher value of T 4 -I determined by Tetralute when added to a TBG solution but there was only a slight increase when it was added to serum. (auth.)

  9. Behaviour of hormone parameters and equivalent iodide clearance (TcTu) on suppressive T4 treatment of enthyroid struma

    International Nuclear Information System (INIS)

    Greis, W.

    1978-01-01

    84 patients with euthyroid diffuse struma were stabilised at the individually necessary thyroxine dose by means of TcTU, T 4 , and NTR. As long-term medication, 100μg l-thyroxin were required in 143% of the patients, 150 μg in 83.3% of the patients, and 200 μg in 2.4% of the patients. After 8 to 12 weeks of therapy, the TcTU as an estimate of the iodide clearance was suppressed to 0.1 to 3.5 ( x +- s). T 4 and NTR values were near the upper limit of the normal at a normal T 3 level. After administration of 150 μg thyroxine per day for 12 weeks and 200μg thyroxine for 4 weeks, TcTU is suppressed to a comparable extent while the weaker suppressive effect of a 12 weeks' medication with 100μg thyroxine could not be improved even by a prolonged therapy. After one year of treatment, calculations of the thyroid surface in scintiscans showed a successful therapy in 82% of the patients while the circumference of the neck had become smaller only in 60% of the patients. Therapy was generally less successful in patients over 18 years of age. (orig.) [de

  10. Serum free-thyroxine modifications with age and in normal pregnancy

    International Nuclear Information System (INIS)

    Degrossi, O.J.; Altschuler, N.; Watanabe, T.; Pinkas, M.; Damilano, S.; Garcia del Rio, H.

    1982-01-01

    The possibility of using radioimmunoassay techniques (RIA) in the assessment of circulating thyroid hormones, total thyroxine (T4) and triiodothyronine (T3) has particularly increases the diagnosis of thyroid diseases. Thyroidal hormones circulate bound to proteins; therefore, variations in the transport capacity of the latter will produce important modifications in the T4 and T3 figures. Only small fractions, less than 0.05% for T4 and than 0.5% for T3, circulate in the free form and are considered as metabolically active forms of both hormones. In order to attain a correct clinical valuation, the rates of the free fractions as well as the total rates of these hormones must be known. Recently, these studies of free hormones are carried out by means of RIA, with the consequent advantages. The variations in serum free thyroxine (FT4) under certain physiogical conditions, such as for different ages and during pregnancy, were particularly studied

  11. Comparison of Amerlex, NML, and Ames total thyroxine and triiodothyronine radioimmunoassay kits

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, T J; Turnbull, P A [Commonwealth Pathology Lab., Toowoomba (Australia). Dept. of Endocrinology

    1982-03-01

    An evaluation of the Amerlex system for determination of total thyroxine (T4) and total triiodothyronine (T3) is described. The within- and between-batch precisions were acceptable, and analyses of quality control material and linearity studies demonstrated good accuracy at the clinical decision levels. The correlations obtained with NML and Ames T4 and T3 kit methods were highly significant. The Amerlex T4 and T3 methods are rapid, technically simple, and, coupled with excellent precision and accuracy, present significant advantages.

  12. Comparison of Amerlex, NML, and Ames total thyroxine and triiodothyronine radioimmunoassay kits

    International Nuclear Information System (INIS)

    Wilke, T.J.; Turnbull, P.A.

    1982-01-01

    An evaluation of the Amerlex system for determination of total thyroxine (T4) and total triiodothyronine (T3) is described. The within- and between-batch precisions were acceptable, and analyses of quality control material and linearity studies demonstrated good accuracy at the clinical decision levels. The correlations obtained with NML and Ames T4 and T3 kit methods were highly significant. The Amerlex T4 and T3 methods are rapid, technically simple, and, coupled with excellent precision and accuracy, present significant advantages. (author)

  13. Predicting thyroxine requirements following total thyroidectomy.

    Science.gov (United States)

    Mistry, Dipan; Atkin, Stephen; Atkinson, Helen; Gunasekaran, Sinnappa; Sylvester, Deborah; Rigby, Alan S; England, R James

    2011-03-01

    Optimal thyroxine replacement following total thyroidectomy is critical to avoid symptoms of hypothyroidism. The aim of this study was to determine the best formula to determine the initiated replacement dose of levothyroxine immediately following total thyroidectomy. Prospective study. All patients were initiated on 100 μg levothyroxine and titrated to within the reference range for TSH and free T4. Correlations to height, weight, age, lean body mass (LBM), body surface area (BSA) and body mass index (BMI) were calculated. One hundred consecutive adult patients underwent total thyroidectomy for non-malignant disease. Comparison between three methods of levothyroxine dose prediction, aiming for a levothyroxine dose correct to within 25 μg of actual dose required. Correlations were seen between levothyroxine dose and patient age (r=-0.346, Pregression equation was calculated (predicted levothyroxine dose=[0·943 × bodyweight] + [-1.165 × age] + 125.8), simplified to (levothyroxine dose= bodyweight - age + 125) pragmatically. Initiating patients empirically on 100 μg post-operatively showed that 40% of patients achieved target within 25 μg of their required dose; this increased to 59% when using a weight-only dose calculation (1.6 μg/kg) and to 72% using the simplified regression equation. A simple calculated regression equation gives a more accurate prediction of initiated levothyroxine dose following total thyroidectomy, reducing the need for outpatient attendance for dose titration. © 2011 Blackwell Publishing Ltd.

  14. Lower neonatal screening thyroxine concentrations in Down syndrome newborns

    NARCIS (Netherlands)

    van Trotsenburg, A. S. P.; Vulsma, T.; van Santen, H. M.; Cheung, W.; de Vijlder, J. J. M.

    2003-01-01

    There is an unexplained higher incidence of congenital hypothyroidism (CH) detected by T-4-based neonatal screening programs and a very high prevalence of (mild) plasma TSH elevation in young children with Down syndrome (DS). To determine whether newborns with DS have decreased blood T-4

  15. Serum thyroxine concentrations after radioactive iodine therapy in cats with hyperthyroidism

    International Nuclear Information System (INIS)

    Meric, S.M.; Hawkins, E.C.; Washabau, R.J.; Turrel, J.M.; Feldman, E.C.

    1986-01-01

    Thirty-one cats with hyperthyroidism were given one dose of radioactive iodine (131I) IV. Serum thyroxine (T4) concentrations were measured before treatment in all cats, at 12-hour intervals after treatment in 10 cats, and at 48-hour intervals after treatment in 21 cats. Serum T4 concentrations also were measured one month after 131 I therapy in 29 cats. Activity of 131I administered was 1.5 to 6.13 mCi, resulting in a dose of 20,000 rads to the thyroid. Serum T4 concentrations before 131 I administration were 5.3 to 51.0 micrograms/dl, with a median T4 concentration of 11.0 micrograms/dl. Serum T4 decreased most rapidly during the first 3 to 6 days after treatment. Sixteen cats (55%) had normal serum thyroxine concentrations by day 4 after 131I administration, and 23 cats (74%) were euthyroxinemic by day 8 after treatment. One month after administration of 131I, the 29 cats evaluated were clinically improved, and 24 (83%) of the 29 cats evaluated had normal serum T4 concentrations, 3 cats (10%) remained hyperthyroxinemic, and 2 cats (7%) were hypothyroxinemic. Therefore, administration of 131I was a safe and effective method to quickly decrease serum T4 concentrations in hyperthyroid cats

  16. Exogenous thyroxine improves glucose intolerance in insulin-resistant rats.

    Science.gov (United States)

    Vazquez-Anaya, Guillermo; Martinez, Bridget; Soñanez-Organis, José G; Nakano, Daisuke; Nishiyama, Akira; Ortiz, Rudy M

    2017-03-01

    Both hypothyroidism and hyperthyroidism are associated with glucose intolerance, calling into question the contribution of thyroid hormones (TH) on glucose regulation. TH analogues and derivatives may be effective treatment options for glucose intolerance and insulin resistance (IR), but their potential glucoregulatory effects during conditions of impaired metabolism are not well described. To assess the effects of thyroxine (T 4 ) on glucose intolerance in a model of insulin resistance, an oral glucose tolerance test (oGTT) was performed on three groups of rats (n = 8): (1) lean, Long Evans Tokushima Otsuka (LETO), (2) obese, Otsuka Long Evans Tokushima Fatty (OLETF) and (3) OLETF + T 4 (8.0 µg/100 g BM/day × 5 weeks). T 4 attenuated glucose intolerance by 15% and decreased IR index (IRI) by 34% in T 4 -treated OLETF compared to untreated OLETF despite a 31% decrease in muscle Glut4 mRNA expression. T 4 increased the mRNA expressions of muscle monocarboxylate transporter 10 (Mct10), deiodinase type 2 (Di2), sirtuin 1 (Sirt1) and uncoupling protein 2 (Ucp2) by 1.8-, 2.2-, 2.7- and 1.4-fold, respectively, compared to OLETF. Activation of AMP-activated protein kinase (AMPK) and insulin receptor were not significantly altered suggesting that the improvements in glucose intolerance and IR were independent of enhanced insulin-mediated signaling. The results suggest that T 4 treatment increased the influx of T 4 in skeletal muscle and, with an increase of DI2, increased the availability of the biologically active T 3 to upregulate key factors such SIRT1 and UCP2 involved in cellular metabolism and glucose homeostasis. © 2017 Society for Endocrinology.

  17. Role of beta adrenoceptors in the hypertrophic response to thyroxine

    International Nuclear Information System (INIS)

    Eliades, D.; Weiss, H.R.

    1989-01-01

    The ability of beta-adrenoceptor blockade to reduce the hypertrophic response to thyroxine (T4, 0.5 mg/kg per day, s.c.) was tested in New Zealand white rabbits. Two beta-adrenergic blocking agents, one a full antagonist (propranolol, 9.6 mg/kg per day) and the other a partial agonist (pindolol, 0.96 mg/kg per day) were administered in combination with T4 in an effort to reduce myocardial hypertrophy. A 3 and 16 day group were generated to test the time course of the hypertrophic and receptor responses. Coronary blood flow was measured using radioactive microspheres, and beta-adrenoceptor number and affinity were measured using 125I(-) pindolol as the radioligand. T4 increased coronary blood flow to 1.95 times control values in the 3 day group and 2.2 times control levels in the 16 day group; beta-adrenoceptor number was increased similarly in 3 and 16 day groups to 1.9 times control Bmax levels. Heart weight (HW) to body weight (BW) ratios were significantly increased in only the 16 day group to 1.22 and 1.61 times control, respectively. Treatment with propranolol + T4 blunted the coronary blood flow increase, but receptor upregulation occurred to the same extent as with either substance alone. The HW/BW was increased to 1.49 times control. Pindolol + T4 did not decrease coronary blood flow but blocked beta-adrenoceptor upregulation. The HW was reduced to control levels and the HW/BW ratio was 1.40 times control and significantly decreased from T4 alone. Thus, pindolol was effective in reducing the hypertrophic response to T4, whereas propranolol was only moderately effective in doing so

  18. The effect of thyroxine on silk gland and the effect of two thyroxine ...

    African Journals Online (AJOL)

    The influence of feeding mulberry leaves treated with thyroxine to the growth of the silk gland, and the effect of two different mulberry species, that is, Morus nigra and Morus multicaulis treated with thyroxine on silk quality in the silkworm were studied. The silk glands from thyroxine treated Bombyx mori larvae weighed ...

  19. The effects of thyroxine on metabolism and water balance in a desert-dwelling rodent, Merriam's kangaroo rat (Dipodomys merriami).

    Science.gov (United States)

    Banta, Marilyn R; Holcombe, Dale W

    2002-01-01

    Desert-dwelling mammals such as Merriam's kangaroo rat (Dipodomys merriani) need to conserve both energy and water to survive desert conditions characterized by aridity and low productivity. The thyroid hormone thyroxine increases both basal metabolic rate and urinary water loss in mammals. Increases in basal metabolism and urinary water loss are likely to be detrimental to D. merriami, therefore the regulation of this hormone may be important. To examine the effects of thyroxine in this species, we implanted adult kangaroo rats with pellets designed to release specific doses of thyroxine at a constant rate for 90 days or a placebo pellet. We measured plasma thyroxine concentration, basal metabolic rate, food consumption, urine concentration and water loss in all implanted animals. Thyroxine implants significantly increased both plasma thyroxine and basal metabolic rate in a relatively dose-dependent manner. In response to thyroxine. kangaroo rats increased food consumption only slightly, but this small increase was sufficient to compensate for their elevated metabolic rates. Neither urine concentration nor water loss varied among treatment groups. Thyroxine increased energy expenditure but not water loss in this species.

  20. Production and use of thyroxine antisera in radioimmunoassay technique

    International Nuclear Information System (INIS)

    Abbas, Sumaia Hussein

    2000-06-01

    This study describes the production of antisera from sheep and its use in the determination of thyroxine hormone (T 4 ) level in serum using radioimmunoassay (RIA) technique. In this study two local sheep (Ovis aris) were subjected to immunization against human T 4 immunogen, sera obtained from both sheep after each injection were subjected to evaluation through titration in a purified and non purified form. The produced antibodies were used to assemble a kit for the determination of total human serum thyroxine. Different separation techniques were tried, (second antibody polyethylene glycol (PEG) assisted precipitation, polystyrene beads and magnetisable particles solid phases). For the PEG assisted precipitation, local antiserum and that produced by the North East Thamus Region Immunoassay (NETRIA donkey anti-sheep serum (DASS) as second antibodies) were tried. The final dilutions of the anti-T 4 antibody used were 1/4000 in a liquid phase using second antibody PEG assisted separation, 1/3000 using magnetizable particles and a dilution of 1/10,000 using polystyrene beads solid phase for separation. Optimization of T 4 assay conditions including incubation temperature and reaction time were done. Tests for T 4 assay validation (linearity, recovery and responsibility) were carried out. For linearity and recovery tests, the regression coefficient ranges were found to be from (0.8 to 0.9) and (0.88 to 0.98) respectively. The assay was found to be reproducible where the coefficients of variation within and between assays were less than 10%. The locally developed assay was found to be comparable with NETRIA assay as a reference method with a correlation coefficient of 0.88, 0.93 and 0.87 for PEG assisted separation, magnetizable particles and polystyrene beads techniques respectively. The clinical validation tests showed a reliable sensitivity, specificity and efficiency with values of 97%, 94% and 96% respectively. When the T 4 concentrations measured using the

  1. Thyroid function in children and adolescents with Hashimoto’s thyroiditis after l-thyroxine discontinuation

    Directory of Open Access Journals (Sweden)

    Giorgio Radetti

    2017-04-01

    Full Text Available Objective: Thyroid function may recover in patients with Hashimoto’s thyroiditis (HT. Design: To investigate thyroid function and the need to resume l-thyroxine treatment after its discontinuation. Setting: Nine Italian pediatric endocrinology centers. Patients: 148 children and adolescents (25 m and 123 f with HT on treatment with l-thyroxine for at least one year. Intervention and main outcome measure: Treatment was discontinued in all patients, and serum TSH and fT4 concentrations were measured at the time of treatment discontinuation and then after 2, 6, 12 and 24 months. Therapy with l-thyroxine was re-instituted when TSH rose >10 U/L and/or fT4 was below the normal range. The patients were followed up when TSH concentrations were between 5 and 10 U/L and fT4 was in the normal range. Results: At baseline, TSH was in the normal range in 139 patients, and was between 5 and 10 U/L in 9 patients. Treatment was re-instituted after 2 months in 37 (25.5% patients, after 6 months in 13 patients (6.99%, after 12 months in 12 patients (8.6%, and after 24 months in an additional 3 patients (3.1%. At 24 months, 34 patients (34.3% still required no treatment. TSH concentration >10 U/L at the time of diagnosis was the only predictive factor for the deterioration of thyroid function after l-thyroxine discontinuation. Conclusions: This study confirms that not all children with HT need life-long therapy with l-thyroxine, and the discontinuation of treatment in patients with a TSH level <10 U/L at the time of diagnosis should be considered.

  2. Iodine versus thyroxine in treatment of simple goiter in sudan

    International Nuclear Information System (INIS)

    Hassan, A.M; Khangi, F.A; Ali, N.I.; Besheir, S.O.; Eltom, M.A.

    2003-01-01

    This study was designed to update the existing information concening goiter prevalence and iodine deficiency disorders in omdurman city and to compare the effects of thyroxine versus iodine in the treament of simlpe goiter. Thyroxine in different doses is commonly used in treatment of simple goiter in Sudan. The goiter survey was conducted in Omdurman secondary school for girls (Khartoum state). Of the goitrous subjects 99 girls were selected to participate in the treament protocol. A control group of 54 non-goitrous subjects from the same school were also included. The goitrous subjects were divided randomly into two groups receiving either daily dose of 100 μg thyroxine for six months or a single dose of 400 mg of oral iodine in the form of iodized oil. Blood and urine samples were collected from the goitrous and control group and recollected from the goitrous subjects every six weeks for six months. Goiter size was assessed at 3,6 and 14 months after the commencement of the treament. Blood samples were analyzed for serum level of T4,T3 and TSH using sensitive radioimmunoassay techniques. Urine samples were analyzed for urinary iodine excretion. Goiter was found in 139 students out of 1034, (13.4%). They were all euthyroid with simple diffuse goiter.T4 in the goitrous group (93.3±26.9 nmole /L (mean±SD)) was significanty lower than in the control group (106.4±18.2nmole/L,p<0.05). T3 was significantly higher in the goitrous (1.6±0.4 nmole/L) than in the control group (1.3±0.3 nmole/L,p<0.05) while there was no significant difference in the mean serum TSH or urinary iodine excretion between the two groups. More than 70% of the goitrous and the control subjects excreted 2 μg 1 / dI or less. Of the subjects treated with thyroxine 87.8% showed complete disappearance or definite regression of the goiter size compared with 90% of those received iodine after the treament.(Author) =

  3. Iodine versus thyroxine in treatment of simple goiter in sudan

    International Nuclear Information System (INIS)

    Eltom, M.A.; Ali, N.

    2003-01-01

    This study was designed to update the existing information concerning goiter prevalence and iodine deficiency disorders in Omdurman city and to compare the effects of thyroxine versus iodine in the treatment of simple goiter. Thyroxine in different doses is commonly used in treatment of sample goiter in sudan. This goiter survey was conducted in Omdurman secondary school for girls (Khartoum state). Of the goitrous subjects 99 girls were selected to participate in the treatment protocol. A control group of 54 non-goitrous subjects from the same school were also included. This goitrous subjects were divided randomly into two groups receiving either daily dose of 100 μg thyroxine for six months or a single dose of 400 mg of oral iodine in the form iodized oil. Blood and urine samples were collected from the goitrous and control group and recollected from the goitrous subjects every six weeks for six months. Goiter size was assessed at 3,6 and 14 months after the commencement of the treatment. Blood samples were analyzed for serum level of T4, T3 and TSH using sensitive radioimmunoassay techniques. Urine samples were analyzed for urinary iodine excretion. Goiter was found in 139 students out of 1034, (13.4%). They were all euthyroid with simple diffuse goiter. T4 in the goitrous group (93.3±26.9 n mole/L (mean±SD)) was significantly lower than in the control group (106.4±18.2 n mole /L, p<0.05). T3 was significantly higher in the goitrous (1.3 ±0.3 n mole/L, p<0.05) while there was no significant difference in the mean serum TSH or urinary iodine excretion between the two groups. More than 70% of goitrous and the control subjects excreted 2 μg I /dl or less. Of the subjects treated with thyroxine 87.8% showed complete disappearance or definite regression of the goiter sized compared with 90% of those received iodine after the treatment

  4. Thyroxin Is Useful to Improve Sperm Motility

    Directory of Open Access Journals (Sweden)

    Mendeluk Gabriela Ruth

    2016-07-01

    Full Text Available Background The aim of this study was to evaluate the non-genomic action of thyroxin on sperm kinetic and its probable use to improve sperm recovery after applying an en- richment method like “swim-up” in comparison with the available one, pentoxifylline. Materials and Methods This is an experimental study. A total of 50 patients were re- cruited, followed by infertility consultation. Conventional sperm assays were performed according to World Health Organization criteria-2010 (WHO-2010. A Computer Aided Semen Analysis System was employed to assess kinetic parameters and concentrations. Number of the motile sperm recovered after preparation technique was calculated. Results Addition of T4 (0.002 µg/ml to semen samples increased hypermotility at 20 minutes (control: 14.18 ± 5.1% vs. 17.66 ± 8.88%, P<0.03, data expressed as mean ± SD and remained unchanged after 40 minutes. Significant differences were found in the motile sperm recovered after swim-up (control: 8.93×106 ± 9.52× 06vs. 17.20×106 ± 21.16×106, P<0.03, achieving all of the tested samples a desirable threshold value for artificial insemination outcome, while adding pentoxifylline increased the number of recovered sperm after swim-up in 60% of the studied cases. No synergism between two treatments could be determined. Conclusion We propose a new physiological tool to artificially improve insemination. The discussion opens windows to investigate unknown pathways involved in sperm ca- pacitation and gives innovative arguments to better understand infertility mechanisms.

  5. Radioimmunoassay detection of levels of triiodothyronine and thyroxine in Mangalarga Marchador equine

    International Nuclear Information System (INIS)

    Viana, F.A.B.; Pessoa, J.M.; Biondini, J.

    1991-01-01

    Serum levels of triiodothyronine (T 3 ) and thyroxine (T 4 ) were determined in equine of Mangalarga Marchador breed through radioimmunoassay. Forty-two animals (17 males and 25 females), with age ranging from two to eighteen years, were utilized. The values recorded for males and females were, respectively: 101.68 ± 23.44 and 71.14 ± 18.82 ng/d l of T 3 (P 4 (P<0.05). (author). 10 refs, 1 tab

  6. Effect of subclinical hypothyroidism on the skeletal system and improvement with short-term thyroxine therapy.

    Science.gov (United States)

    Gao, Cuixia; Wang, Yu; Li, Tingting; Huang, Jing; Tian, Limin

    2017-10-27

    The purpose of the study was to observe changes in the skeletal system of rats with subclinical hypothyroidism (SCH) and to determine whether L-thyroxine (L-T4) administration suppresses those changes. Sixty male Wistar rats were randomly divided into control, SCH, and SCH+T4 groups. SCH was induced in rats by administration of methimazole (MMI), and rats in the SCH+T4 group were treated with L-T4 after 45 days of MMI administration. The SCH group had higher thyroid-stimulating hormone (TSH) level than the control and SCH+T4 groups. There were no differences in serum thyroid hormone (FT4 and FT3) levels among the three groups. Bone mineral density; serum levels of BALP and TRACP-5b, two bone metabolic markers; and the biomechanical properties of the femurs were lower in the SCH group than in the control group. After L-T4 treatment, serum BALP and TRACP-5b levels and the femur biomechanical properties were higher in the SCH+T4 than the SCH group. Histopathological examination revealed damage to the structure of the femur trabecular bone network in rats with SCH, and L-T4 treatment improved this condition to some extent. These findings demonstrate that L-T4 treatment ameliorates the destructive effects of SCH on the skeletal system in rats.

  7. Thyroxine and triiodothyronine content in commercially available thyroid health supplements.

    Science.gov (United States)

    Kang, Grace Y; Parks, Jonathan R; Fileta, Bader; Chang, Audrey; Abdel-Rahim, Maged M; Burch, Henry B; Bernet, Victor J

    2013-10-01

    As defined by the Dietary Supplement Health and Education Act 1997, such substances as herbs and dietary supplements fall under general Food and Drug Administration supervision but have not been closely regulated to date. We examined the thyroid hormone content in readily available dietary health supplements marketed for "thyroid support." Ten commercially available thyroid dietary supplements were purchased. Thyroid supplements were dissolved in 10 mL of acetonitrile and water with 0.1% trifloroacetic acid and analyzed using high-performance liquid chromatography for the presence of both thyroxine (T4) and triiodothyronine (T3) using levothyroxine and liothyronine as a positive controls and standards. The amount of T4 and T3 was measured separately for each supplement sample. Nine out of 10 supplements revealed a detectable amount of T3 (1.3-25.4 μg/tablet) and 5 of 10 contained T4 (5.77-22.9 μg/tablet). Taken at the recommended dose, 5 supplements delivered T3 quantities of greater than 10 μg/day, and 4 delivered T4 quantities ranging from 8.57 to 91.6 μg/day. The majority of dietary thyroid supplements studied contained clinically relevant amounts of T4 and T3, some of which exceeded common treatment doses for hypothyroidism. These amounts of thyroid hormone, found in easily accessible dietary supplements, potentially expose patients to the risk of alterations in thyroid levels even to the point of developing iatrogenic thyrotoxicosis. The current study results emphasize the importance of patient and provider education regarding the use of dietary supplements and highlight the need for greater regulation of these products, which hold potential danger to public health.

  8. The influence of thyroxine and propyl thiouracil on Parastrongylus malaysiensis infection in rats.

    Science.gov (United States)

    Kamis, A B; Ahmad, R A; Chang, J S; Ambu, S

    1994-01-01

    Daily intramuscular injection with thyroxine (T4) at a dose of 2.5 micrograms/100 g body weight decreased the larvae and adult worm burden of Parastrongylus malaysiensis in the brain and pulmonary arteries of male Sprague-Dawley albino rats. In contrast, rats treated with propyl thiouracil (PTU), an antithyroid drug, at a dose of 3.75 mg/100 g body weight retained greater numbers of larvae and adult worms. The results may reflect the contrasting immunomodulatory effects of T4 and PTU that influence the susceptibility of the host.

  9. Recovery following Thyroxine Treatment Withdrawal, but Not Propylthiouracil, Averts In Vivo and Ex Vivo Thyroxine-Provoked Cardiac Complications in Adult FVB/N Mice

    Directory of Open Access Journals (Sweden)

    Nancy S. Saad

    2017-01-01

    Full Text Available Persistent cardiovascular pathology has been described in hyperthyroid patients even with effective antithyroid treatment. Here, we studied the effect of a well-known antithyroid drug, propylthiouracil (PTU; 20 mg/kg/day, on thyroxine (T4; 500 µg/kg/day-induced increase in blood pressure (BP, cardiac hypertrophy, and altered responses of the contractile myocardium both in vivo and ex vivo after 2 weeks of treatment. Furthermore, the potential recovery through 2 weeks of T4 treatment discontinuation was also investigated. PTU and T4 recovery partially reduced the T4-prompted increase in BP. Alternatively, PTU significantly improved the in vivo left ventricular (LV function with no considerable effects on cardiac hypertrophy or ex vivo right ventricular (RV contractile alterations subsequent to T4 treatment. Conversely, T4 recovery considerably enhanced the T4-provoked cardiac changes both in vivo and ex vivo. Altogether, our data is in agreement with the proposal that hyperthyroidism-induced cardiovascular pathology could persevere even with antithyroid treatments, such as PTU. However, this cannot be generalized and further investigation with different antithyroid treatments should be executed. Moreover, we reveal that recovery following experimental hyperthyroidism could potentially ameliorate cardiac function and decrease the risk for additional cardiac complications, yet, this appears to be model-dependent and should be cautiously construed.

  10. Thyroid Function Test in Thyroid Diseases and Pregnancy - The diagnostic value of free thyroxine by RIA -

    International Nuclear Information System (INIS)

    Yoo, M. H.; Yoon, H. J.; Shin, Y. T.; Lee, J. C.; Chung, S. I.; Cho, B. Y.; Lee, M. H.; Lee, M. C.

    1981-01-01

    To evaluate the diagnostic accuracy of the measurement of free thyroxine(FT4) by radioimmunoassay, we measured free T 4 and T 4 , T 3 , T 3 RU, TSH and TBG serum levels by radioimmunoassay in 18 healthy persons and 52 patients with various thyroid diseases and 11 normal pregnant women. The results are as follows. 1) In 19 cases of overt hyperthyroidism, T 3 , free T 4 and FTI, T 4 /TBG ratio reflect hyperfunction in all cases. T 4 is increased in 94%(18/19) and TBG and TSH are decreased in 79%(15/19). 2) In 8 patients with overt hypothyroidism, TSH is increased in all cases and free T 4 and FTI is decreased in all cases. T 4 is decreased in 87.5%(7/8), T 3 is decreased in 75%(6/8) and T 4 /TBG ratio is decreased in 62.5%(5/8). 3) In 5 patients who are clinically in euthyroid state after treatment of hyperthyroidism, T , 4 free T 4 , FTI and TSH are in the normal range in all cases and T 3 is normal in 60%(3/5) and slightly increased in 40%(2/5). 4) In 10 patients who showed clinically borderline hypothyroidism after treatment of hyperthyroidism, TSH is increased in all cases and free T 4 and FTI are decreased in all cases, but T 4 and T 3 , T 4 /TBG ratio are in the normal limit in all cases. So after treatment of hyperthyroidism, TSH, free T 4 or FTI are recommended as optimal function test. 5) In normal pregnancy, free T 4 , FTI and T 4 /TBG ratio reflect normal function, but the other parameters unreliable due to the influence of increased TBG. Also TBG and TSH level in pregnancy is increased significantly compared with normal healthy control group. 6) The coefficients of correlation between T 4 and FTI were 0.862(p 4 and T 4 /TBG ratio. In most patients, diagnostic value of free T 4 was comparable and even superior to FTI, so free T 4 measurement can be used routinely with thyrotropin assay in the diagnosis of hypothyroidism or with T 3 for the diagnosis of hyperthyroidism.

  11. Measurement of free thyroxine and free triiodothyronine concentrations by DPC RIA kits

    International Nuclear Information System (INIS)

    Kasagi, Kanji; Kousaka, Tadako; Hatabu, Hiroto; Tokuda, Yasutaka; Iida, Yasuhiro; Konishi, Junji

    1988-01-01

    'DPC RIA' kits for measuring free triiodothyronine (T3) and free thyroxine (T4) were fundamentally and clinically studied. Standard curves for incubation temperature and time were favorable. The present kits yielded satisfactory precision and reproducibility. The upper and lower limits of the normal range for T4 were 0.88 ng/dl and 2.08 ng/dl, respectively. The serum concentration of T4 was 3.91 ng/dl or more for hyperthyroidism and 0.57 ng/dl or less for hypothyroidism, allowing discrimination between the two diseases. For T3, the upper and lower limits of the normal range were 1.45 ng/dl and 3.45 ng/dl, respectively. In pregnant women and patients with decreased or increased levels of thyroxine binding globulin (TBG), the serum T3 concentration lay within the normal range. Low free T4 and T3 levels were found in 22 % and 67 %, respectively, of patients with serious non-thyroidal illness (NTI). There was a good correlation between the present kits and the other commercially available kits. Measurements of free T3 and T4 obtained by ''Amerlex RIA'' kits tended to be lower than those by the present kits in pregnant women and NTI patients with hypoalbuminemia. In view of the simplified procedure, satisfactory precision and reproducibility, and the lack of influences of serum albumin and TBG, the present kits have a potential in routine use. (Namekawa, K.)

  12. Endothelial Functioning and Hemodynamic Parameters in Rats with Subclinical Hypothyroid and the Effects of Thyroxine Replacement.

    Directory of Open Access Journals (Sweden)

    Cuixia Gao

    Full Text Available Subclinical hypothyroidism (SCH and its associations with atherosclerosis (AS and cardiovascular disease remain controversial. The purpose of our study was to observe changes in endothelial functioning and hemodynamics in rats with SCH and to determine whether L-thyroxine (L-T4 administration affects these changes.In total, sixty male Wistar rats were randomly divided into the following three groups with 20 rats each: control euthyroid rats, SCH rats and SCH rats that had been treated with thyroxine (SCH+T4. The SCH rats were induced by administration of 10 mg x kg(-1 x d(-1 methimazole (MMI once daily by gavage for 3 months. The SCH+T4 rats were administered the same dose of MMI for three months in addition to 2 μg x kg(-1 x d(-1 L-T4 once daily by gavage after 45 days of MMI administration. The control rats received physiological saline via gavage.The SCH group had significantly higher thyroid-stimulating hormone (TSH, total cholesterol (TC, low-density lipoprotein cholesterol (LDL-C, and endothelin (ET levels and a lower nitric oxide (NO level than the control and SCH+T4 groups. The tail and carotid artery blood pressures, left ventricular systolic pressure, heart rate and aorta ventralis blood flow were significantly lower in the SCH group than in the control and SCH+T4 groups. ACH treatment caused concentration-dependent relaxation, which was reduced in the SCH arteries compared with the control and SCH+T4 arteries. Histopathological examination revealed the absence of pathological changes in the SCH rat arteries.These findings demonstrate that L-T4 treatment ameliorates endothelial dysfunction and hemodynamic changes in SCH rats.

  13. Transport of thyroxine across the blood-brain barrier is directed primarily from brain to blood in the mouse

    International Nuclear Information System (INIS)

    Banks, W.A.; Kastin, A.J.; Michals, E.A.

    1985-01-01

    The role of the blood-brain barrier (BBB) in the transport of thyroxine was examined in mice. Radioiodinated (hot thyroxine (hT 4 ) administered icv had a half-time disappearance from the brain of 30 min. This increased to 60 min (p 4 ). The Km for this inhibition of hT 4 transport out of the brain by cT 4 was 9.66 pmole/brain. Unlabeled 3,3',5 triiodothyronine (cT 3 ) was unable to inhibit transport of hT 4 out of the brain, although both cT 3 (p 4 (p 3 ) to a small degree. Entry of hT 4 into the brain after peripheral administration was negligible and was not affected by either cT 4 nor cT 3 . By contrast, the entry of hT 3 into the brain after peripheral administration was inhibited by cT 3 (p 4 (p < 0.01). The levels of the unlabeled thyroid hormones administered centrally in these studies did not affect bulk flow, as assessed by labeled red blood cells (/sup 99m/Tc-RBC), or the carrier mediated transport of iodide out of the brain. Likewise, the vascular space of the brain and body, as assessed by /sup 99m/Tc-RBC, was unchanged by the levels of peripherally administered unlabeled thyroid hormones. Therefore, the results of these studies are not due to generalized effects of thyroid hormones on BBB transport. The results indicate that in the mouse the major carrier-mediated system for thyroxine in the BBB transports thyroxine out of the brain, while the major system for triiodothyronine transports hormone into the brain. 14 references, 3 figures, 2 tables

  14. An Evaluation of Thyroid Hormones (T4, T3, and Free T4) Concentrations During Pregnancy

    International Nuclear Information System (INIS)

    Lee, Kyu Bo; Kim, Ji Yeul

    1981-01-01

    Serum concentrations of T 4 , T 3 , and free T 4 were measured by radioimmunoassay in normal pregnant women at trimesters, in postpartum women, and cord blood of neonate. Total T 4 were increased during pregnancy, remarkably high in the first trimester, and also somewhat increased in postpartum, and normal in neonate. Total T 3 were in normal range during pregnancy, but increased in postpartum, whereas decreased in neonate. Free T 4 were decreased in 2nd and 3rd trimesters of pregnancy, however normal in postpartum and neonate.

  15. Development of reagents for radioimmunoassay of: triiodothyronine, thyroxine and thyrotrophin

    International Nuclear Information System (INIS)

    Delgado S, B.; Lavalley E, C.; Ruiz J, A.; Garcia F, C.; Zamorano A, F.

    1991-12-01

    The radioimmunoassay (RIA) of thyroid hormones it is the but it frequents of all the studies carried out by RIA in the laboratories of Nuclear Medicine, these essays are carried out with imported reagents. In the ININ the reagents and the necessary methodology have been developed for the triiodothyronine (T3), thyroxine (T4) and thyrotrophin (TSH). The good titles of the antibodies (Ac) primary for each hormone were of 1:4,000; 1:750 and 1:1,500. The used separation system was of double Ac with PEG to 10%, with titles of 1:10 for the second Ac of lamb. The specific activity for 125-I-T3 and 125-I-T4 oscillate between 850 at 900 μCi / μ g: being this of 90 μ Ci /μg for TSH. To the first two hormones they were added 1-8 aniline naftalen sulfonic acid (ANS) to concentrations of 3 and 2 mg/ml respectively. As buffer for T3 and T4 it was used Tris-HCl pH 8.6 and PBS with normal serum of rabbit (SNC) for TSH. The standards got ready in buffer or free serum of thyroid hormones. The slope of the standard curves varied between -2.3 to -2.7 and the variation intra and inter assay among 4 to 10%. It is had at the moment in the ININ with standardized reagents for the RIA of T3, T4 and TSH, it is hoped to carry out tests in other laboratories and to establish the conditions of stability more appropriate to begin the preparation of pilot reagents. (Author)

  16. Evidence for thyroxine transport by the lung and heart capillary endothelium

    International Nuclear Information System (INIS)

    Heltianu, C.; Dobrila, L.; Antohe, F.; Simionescu, M.

    1989-01-01

    The uptake and transport of carrier-bound thyroxine by the endothelium were investigated by perfusing through the heart and lung of young rats radiolabeled thyroxine bound to prealbumin ([125I]T4Pa) or serum ([125I]T4S). In addition these complexes were tagged to 5-nm gold particles to obtain quantitative (radioassay) and qualitative (autoradiography) data from the same experiment. The complexes (prewarmed at 37 degrees) were perfused in situ at various concentrations (1 to 50 muCi/ml) for time intervals ranging from 5 to 30 min. After thorough washing of the unbound probe, tissue fragments were either measured for total uptake in a gamma counter or processed for electron microscopy autoradiography. The results showed that both the lung and heart take up [125I]T4 complexes by a process that is saturable at low hormone concentration; uptake is completed by free T4 and Pa. In specimens perfused with double-labeled complexes (iodinated and tagged to gold) autoradiography revealed that silver grains and gold particles colocalize predominantly on endothelial plasmalemmal vesicles. The probe appeared first in vesicles open to the capillary lumen (5 min) and further on in vesicles apparently free within the cytoplasm or open to the abluminal front. At 30 min, only silver grains seem to be present in the pericapillary space, on the alveolar epithelial cells, as well as on the nucleus and mitochondria of heart myocytes. The findings suggest that (1) T4Pa uptake by the endothelial cell (EC) is a specific process (possibly via specific binding sites); (2) T4Pa is taken up and transported across capillary EC by plasmalemmal vesicles; (3) in the pericapillary space T4 seems to dissociate from its carrier

  17. Pyrroloquinoline quinone ameliorates l-thyroxine-induced hyperthyroidism and associated problems in rats.

    Science.gov (United States)

    Kumar, Narendra; Kar, Anand; Panda, Sunanda

    2014-08-01

    Pyrroloquinoline quinone (PQQ) is believed to be a strong antioxidant. In this study, we have evaluated its hitherto unknown role in l-thyroxin (L-T4 )-induced hyperthyroidism considering laboratory rat as a model. Alterations in the serum concentration of thyroxin (T4 ) and triiodothyronine (T3 ); lipid peroxidation (LPO) of liver, kidney, heart, muscles and brain; in the endogenous antioxidants such as superoxide dismutase, catalase and glutathione and in serum total cholesterol, high-density lipoprotien, triglycerides, serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT) and urea were evaluated. Administration of l-T4 (500-µg kg(-1) body weight) enhanced not only the serum T3 and T4 levels but also the tissue LPO, serum SGOT, SGPT and urea with a parallel decrease in the levels of antioxidants and serum lipids. However, on simultaneous administration of PQQ (5 mg kg(-1) for 6 days), all these adverse effects were ameliorated, indicating the potential of PQQ in the amelioration of hyperthyroidism and associated problems. Possibly, the curative effects were mediated through inhibition of oxidative stress. We suggest that PQQ may be considered for therapeutic use for hyperthyroidism after dose standardization. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Radioimmunoassay of serum T3, T4 and TSH during anesthesia and operation

    International Nuclear Information System (INIS)

    Gosheva-Antonova, Ts.; Zakharieva, B.; Kurtev, I.

    1987-01-01

    The serum concentrations of thyroxine (T 3 ), triiodothyronine (T 4 ) and thyroid-stimulating hormone (TSH) were determined in 31 partients before and during urologic operations on the 30th and 60th minute since the onset of the operation, performed under endotracheal halotane or neuroleptanesthesia (NLA) in assisted breathing and intravenous drip anesthesia with ketalar-diazepam in spontaneous breathing. There was statistically significant rise in T 4 level, decrease in T 3 and negligible changes in TSH level, in patients operated under halotane anesthesia. In those operated under NLA, T 4 tended initially to be elevated, with subseguent fall to starting level, with a tendency toward rise in TSH and stable unchanged T 3 level. Ketalar-diazepam anesthesia was applied only to patients subjected to transurethral resections. T 4 in them tended to be decreased, while T 3 and TSH showed negligible changes. Since the operations of patients anesthesized with halotane and NLA had similar localizations and severity, the differences in the thyroid hormone reactions could be associated with the type of anesthesia. The negligible changes in TSH are highly suggestive that this hormone is not influenced by the operation stress and anesthetics, and does hot exert regulating effect upon the thyroid status under these conditions. The milder reactions in patients operated under ketalar-diazepam anestesia may largely be associated with the milder operation stress in transurethal resection

  19. Analytical Application of Flow Immunosensor in Detection of Thyroxine and Triiodothyronine in Serum.

    Science.gov (United States)

    Wani, Tanveer A; Zargar, Seema; Majid, Salma; Darwish, Ibrahim A

    2016-11-01

    In this study, an immunosensor based on kinetic exclusion analysis (KinExA) was used for thyroxine (T4) and triiodothyronine (T3) estimation. A KinExA™ 3200 instrument was used for this analysis, which is an automated flow fluorimeter designed to separate free unbound antibody binding sites in reaction mixtures of antibody, antigen, and antibody-antigen complex. A T3-BSA- and T4-BSA-coated polymethyl methacrylate (PMMA) bead microcolumn is generated inside the flow cell of the instrument. A sample mixture containing T3 and T4 with their respective monoclonal antibodies and their complexes are drawn past the microbead column. The unbound T3 or T4 monoclonal antibody binding sites are captured by their respective T3 and T4 antigens coated on the PMMA beads as bovine serum albumin conjugates. Fluorescently labeled secondary antibodies bind to the T3 or T4 antigen-antibody complex to generate fluorescence intensity for analysis. The limit of detection for the T3 and T4 assays was found to be 0.06 and 1.9 ng mL -1 with acceptable precision values. The convenience of the automated KinExA format may be valuable in medical diagnostic laboratories.

  20. Do Thyroxine and Thyroid-Stimulating Hormone Levels Reflect Urinary Iodine Concentrations?

    Science.gov (United States)

    Soldin, Offie P.; Tractenberg, Rochelle E.; Pezzullo, John C.

    2013-01-01

    The toxicity of environmental chemicals such as nitrates, thiocynates, and perchlorates, some therapeutics, and dietary goitrogens can lower thyroidal iodine uptake and result in hypothyroidism and goiter. Iodine sufficiency, essential for normal thyroid hormone synthesis, is critical during gestation to assure that sufficient thyroxine (T4) and iodine reach the developing fetus. Spot urinary iodide (UI) measurements are used globally to indicate and monitor iodine sufficiency of populations. In individuals, however, UI are not routinely measured; instead, normal serum thyroid-stimulating hormone (TSH) and T4 concentrations serve as surrogate indicators of iodine sufficiency as well as thyroidal health. Our objective was to examine the relationship between UI concentrations and serum T4 and TSH concentrations in individuals in an ‘‘iodine-sufficient population.’’ Using a cross-sectional sample of the US population (n = 7628) from the National Health and Nutrition Examination Survey (NHANES III; 1988–1994) database, we examined the relationship among UI, T4, and TSH in pregnant and nonpregnant women and in men (15–44 years). There was a lack of relationship between UI (or UI/Cr) concentrations and serum T4 or TSH concentrations. Therefore, TSH and T4 are not appropriate markers of UI concentrations in this population. Monitoring the status of iodine nutrition of individuals in the United States may be important because serum TSH and T4 concentrations do not indicate low iodine status. PMID:15795649

  1. Effect of selective blockade of oxygen consumption, glucose transport, and Ca2+ influx on thyroxine action in human mononuclear cells

    DEFF Research Database (Denmark)

    Kvetny, J; Matzen, L E

    1990-01-01

    The effect of selective blockade of cellular glucose transporters, Ca2+ influx, and mitochondrial oxygen consumption on thyroxine (T4)-stimulated oxygen consumption and glucose uptake was examined in human mononuclear blood cells. Blockade of glucose transporters by cytochalasin B (1 x 10(-5) mol....../L) and of Ca2+ influx by alprenolol (1 x 10(-5) mol/L) and verapamil (4 x 10(-4) mol/L) inhibited T4-activated glucose uptaken and reduced T4-stimulated oxygen consumption by 20%. Uncoupling of mitochondrial oxygen consumption by azide (1 x 10(-3) mol/L) inhibited T4-stimulated oxygen consumption, but had...... no effect on glucose uptake. We conclude that T4-stimulated glucose uptake in human mononuclear blood cells is dependent on intact glucose transporters and Ca2+ influx, but not on mitochondrial oxygen consumption. However, oxygen consumption is, in part, dependent on intact glucose uptake....

  2. Conversion of L-thyroxine to L-triiodothyronine in the rat liver under in vitro conditions

    International Nuclear Information System (INIS)

    Nauman, A.; Kaminski, T.; Pastuszko, D.

    1979-01-01

    Conversion of thyroxine (T 4 ) to triiodothyronine (T 3 ) has been studied in liver homogenates obtained from normal and hypothyroid rats. Liver homogenates were incubated for 0-60 minutes at 37 0 C in Tris buffer containing sucrose and T 4 , pH 7.4. T 3 generated during incubation was measured by a specific radioimmunoassay of an ethanol extract of the incubates. Conversion rate of T 4 to T 3 by liver homogenates from intact rats was found to be time, protein concentration and substrate concentration (T 4 ) dependent. Heating of homogenate above 60 0 C abolished while cooling significantly decreased the monodeiodination. In homogenates from hypothyroid rats the conversion and its rate were significantly decreased. The results of present study confirmed enzymatic character of monodeiodination reaction. Decreased conversion of T 4 to T 3 in hypothyroidism suggests that biosynthesis of converting enzyme may be regulated by thyroid hormones. (author)

  3. An improved method for the radioimmunoassay of free-thyroxine in serum dialysates

    International Nuclear Information System (INIS)

    Giles, A.F.

    1982-01-01

    A convenient, sensitive radioimmunoassay (using 125 I) of free thyroxine in serum dialysates is described. The method utilizes a solid phase separation system (pre-formed double antibody) and a relatively short incubation period (220 min) with a staggered addition of tracer. Blanks were low and consistent. The normal range for non-pregnant euthyroid samples (n = 59) was 11-23 pmol/l. Third trimester pregnancy samples were mostly within the normal range but at the lower end. Patients on T4 replacement showed a much wider variation in free T4 levels with many samples in the hyperthyroid region. Some hypothyroid samples had undetectable free T4 levels and hyperthyroid samples were frequently greater than 80 pmol/l. (author)

  4. Circadian variations of serum thyrotropin, thyroxine, triiodothyronine, reverse triiodothyronine, corticosterone and lipids in starved rats

    International Nuclear Information System (INIS)

    Zwirska-Korczala, K.; Ostrowska, Z.; Kucharzewski, M.; Marek, B.; Kos-Kudla, B.; Buntner, B.; Swietochowska, E.

    1993-01-01

    We investigated the circadian variation of serum thyrotropin (TSH), thyroxine (T 4 ), triiodothyronine (T 3 ), reverse triiodothyronine (rT 3 ), corticosterone (B) and lipids in male Wistar rats after one-week starvation. Starvation decreased the TSH level and eliminated its 24-h rhythm. The rhythmicity of oscillations of T 3 and B was maintained. Starvation led to a shift in the acrophase of 24-h T 3 and B oscillation and induced the circadian rhythm of T 4 . The T 3 , T 4 and mesor values were lower, while for rT 3 and B they increased. Lipid concentrations remained unchanged in both experimental and control rats. (author). 27 refs, 3 figs, 2 tabs

  5. Triiodothyronine and free thyroxine levels are differentially associated with metabolic profile and adiposity-related cardiovascular risk markers in euthyroid middle-aged subjects.

    Science.gov (United States)

    Roef, Greet L; Rietzschel, Ernst R; Van Daele, Caroline M; Taes, Youri E; De Buyzere, Marc L; Gillebert, Thierry C; Kaufman, Jean-Marc

    2014-02-01

    We have previously shown that in healthy young men, a less favorable body composition is associated with higher free triiodothyronine (fT3) levels within the euthyroid range. Besides, a higher free-triiodothyronine-to-free-thyroxin (fT3-to-fT4) ratio has been related to a less favorable metabolic phenotype and more placental growth in pregnant women. In the present study, we therefore investigated whether serum thyrotropin (TSH), thyroid hormone levels, and the fT3-to-fT4 ratio are associated with metabolic and adiposity-related cardiovascular risk markers in a healthy population of middle-aged euthyroid men and women. Thyroid parameters were measured in 2524 generally healthy subjects from the Asklepios Study (35-55 years, mean age 46 years). Analyses were restricted to 2315 subjects (1138 women and 1177 men), not using thyroid medication, not having anti-TPO levels above clinical cutoff values or TSH levels outside the reference range (0.27-4.2 mU/L). Twenty-seven percent of the women and 47.5% of the men were overweight, while 13% of women and 17% of men were obese. Twenty percent of the subjects were active smokers. Serum thyroid function parameters were determined by electrochemiluminescence. fT3 and the fT3-to-fT4 ratio were positively related to body mass index (BMI), waist circumference, and components of metabolic syndrome, that is, triglycerides, systolic and diastolic blood pressure, and fasting plasma glucose, and negatively with HDL-cholesterol levels, whereas fT4 was negatively associated with BMI, waist circumference, and triglycerides (p<0.001). TSH related positively with total cholesterol levels (p<0.01), triglycerides, and systolic and diastolic blood pressure (p<0.001). The fT3-to-fT4 ratio was further positively associated with the adiposity-related inflammation markers interleukin-6 and high-sensitivity C-reactive protein and to pulse wave velocity. All associations were adjusted for sex, age, height, and smoking, and most associations

  6. Clinical significance of two-step magnetic radioimmunoassay for determining serum free T3 and free T4

    International Nuclear Information System (INIS)

    Chen Bing

    1996-01-01

    The concentrations of the serum free T 3 (FT 3 ), free T 4 (FT 4 ), total triodothyronine (TT 3 ), total thyroxine (TT 4 ) and thyrotropin (TSH) are determined for 355 cases of normal persons, pregnant women and various thyropathetic patients. The normal values of FT 3 and FT 4 are 2.0-8.5 pmol/l, and 9.5-26.5 pmol/l, respectively. Neither FT 3 nor FT 4 is affected by the thyroxine combined with globulin (TBG), which is of unique diagnostic value for those with variable TBG (such as pregnant women hyperthyroidism, hypothyroidism, etc.), FT 3 and FT 4 are the most sensitive indices for diagnosis of hyperthyroidism, and hypothyroidism, respectively. In addition, FT 3 and FT 4 can greatly contribute to the observation of curative effectiveness under treatment

  7. Comparative effectiveness of carvedilol and propranolol on glycemic control and insulin resistance associated with L-thyroxin-induced hyperthyroidism--an experimental study.

    Science.gov (United States)

    Bhatt, Parloop; Makwana, Dharmesh; Santani, Devdas; Goyal, Ramesh

    2007-05-01

    The present study was undertaken to investigate the effectiveness of adrenergic antagonists carvedilol and propranolol on L-thyroxin-induced cardiovascular and metabolic disturbances in rats. Treatment with L-thyroxin sodium (75 mg/kg body mass, s.c., every alternate day for 3 weeks), produced a significant increase in food and water intake, body temperature, heart rate, systolic blood pressure, along with an increase in serum T3, T4, and triglyceride levels. Besides a significant reduction in body mass, serum levels of TSH and cholesterol were also reduced following L-thyroxin treatment. Carvedilol (10 mg/kg body mass, orally) and propranolol (10 mg/kg body mass, i.p.) administered daily in the third week to 2 separate groups of L-thyroxin-treated animals reversed thyroxin-induced loss in body mass and rise in body temperature, blood pressure, and heart rate. Propranolol treatment increased TSH levels and decreased T3 and T4 levels in hyperthyroid animals, whereas carvedilol did not produce any effect on thyroid hormones. Carvedilol treatment reversed thyroxin induced hypertriglyceridemia, whereas propranolol treatment had no effect. Both carvedilol and propranolol prevented decrease in cholesterol levels induced by thyroxine. Compared with normal animals, L-thyroxin-treated animals showed a state of hyperglycemia, hyperinsulinaemia, impaired glucose tolerance, and insulin resistance, as inferred from elevated fasting serum glucose and insulin levels, higher area under the curve over 120 min for glucose, and decreased insulin sensitivity index (KITT). Propranolol and carvedilol treatment significantly decreased fasting serum glucose levels. Treatment with propranolol did not alter serum insulin levels, area-under-the-curve glucose, or KITT values. However, treatment with carvedilol significantly reduced area-under-the-curve glucose, decreased fasting serum insulin levels and significantly increased KITT values. In conclusion, carvedilol appears to produce

  8. A randomized, masked study of triiodothyronine plus thyroxine administration in preterm infants less than 28 weeks of gestational age: Hormonal and clinical effects

    NARCIS (Netherlands)

    Valerio, Paolo G.; van Wassenaer, Aleid G.; de Vijlder, Jan J. M.; Kok, Joke H.

    2004-01-01

    A randomized, placebo-controlled, masked study was conducted of the responses of thyroid parameters, cortisol, and the cardiovascular system to a single dose of triiodothyronine (T-3) 24 h after birth, followed by a daily dose of thyroxine (T-4) during 6 wk to infants <28 wk gestational age.

  9. Thyroxine modifies the effects of growth hormone in Ames dwarf mice.

    Science.gov (United States)

    Do, Andrew; Menon, Vinal; Zhi, Xu; Gesing, Adam; Wiesenborn, Denise S; Spong, Adam; Sun, Liou; Bartke, Andrzej; Masternak, Michal M

    2015-04-01

    Ames dwarf (df/df) mice lack growth hormone (GH), thyroid stimulating hormone and prolactin. Treatment of juvenile df/df mice with GH alone stimulates somatic growth, reduces insulin sensitivity and shortens lifespan. Early-life treatment with thyroxine (T4) alone produces modest growth stimulation but does not affect longevity. In this study, we examined the effects of treatment of juvenile Ames dwarf mice with a combination of GH + T4 and compared them to the effects of GH alone. Treatment of female and male dwarfs with GH + T4 between the ages of 2 and 8 weeks rescued somatic growth yet did not reduce lifespan to match normal controls, thus contrasting with the previously reported effects of GH alone. While the male dwarf GH + T4 treatment group had no significant effect on lifespan, the female dwarfs undergoing treatment showed a decrease in maximal longevity. Expression of genes related to GH and insulin signaling in the skeletal muscle and white adipose tissue (WAT) of female dwarfs was differentially affected by treatment with GH + T4 vs. GH alone. Differences in the effects of GH + T4 vs. GH alone on insulin target tissues may contribute to the differential effects of these treatments on longevity.

  10. Radioimmunoassay of thyroxine and triiodothyronine in urine using extraction and separation on Sephadex columns

    International Nuclear Information System (INIS)

    Rogowski, P.; Siersbaek-Nielsen, K.

    1977-01-01

    Radioimmunological methods for the determination of thyroxine (T4) and triiodothyronine (T3) in urine have been developed. The methods are based on trapping of T4 and T3 from unextracted urine, followed by separation between free and antibody bound hormone on the same Sephadex column. The T4 method has been compared to a competitive protein binding (CPB) assay using ethyl acetate extraction. The methods are evaluated in sixty-seven euthyroid controls, twenty-four hyperthyroid and seven hypothyroid patients. In the T4 RIA detection limit was 3.9 pg, intra-assay coefficient of variation (cv) was 5.2% and inter-assay cv was 6.9%. In the T3 RIA detection limit was 7.2 pg, intra-assay cv 3.9% and inter-assay cv 10.8%. Recovery of added amounts of hormones and serial dilutions gave satisfactory results. The CPB assay was found unreliable with unspecific and false high values. In euthyroid controls 24 h urinary T4 excretion as measured by RIA was 1.8+-0.5 nmol, and urinary T3 excretion was 0.7+-0.3 nmol. T4 and T3 excretion was greatly elevated in hyperthyroid patients and decreased in hypothyroidism. (Auth.)

  11. Thyroxin treatment protects against white matter injury in the immature brain via brain-derived neurotrophic factor.

    Science.gov (United States)

    Hung, Pi-Lien; Huang, Chao-Ching; Huang, Hsiu-Mei; Tu, Dom-Gene; Chang, Ying-Chao

    2013-08-01

    Low level of thyroid hormone is a strong independent risk factor for white matter (WM) injury, a major cause of cerebral palsy, in preterm infants. Thyroxin upregulates brain-derived neurotrophic factor during development. We hypothesized that thyroxin protected against preoligodendrocyte apoptosis and WM injury in the immature brain via upregulation of brain-derived neurotrophic factor. Postpartum (P) day-7 male rat pups were exposed to hypoxic ischemia (HI) and intraperitoneally injected with thyroxin (T4; 0.2 mg/kg or 1 mg/kg) or normal saline immediately after HI at P9 and P11. WM damage was analyzed for myelin formation, axonal injury, astrogliosis, and preoligodendrocyte apoptosis. Neurotrophic factor expression was assessed by real-time polymerase chain reaction and immunohistochemistry. Neuromotor functions were measured using open-field locomotion (P11 and P21), inclined plane climbing (P11), and beam walking (P21). Intracerebroventricular injection of TrkB-Fc or systemic administration of 7,8-dihydroxyflavone was performed. On P11, the HI group had significantly lower blood T4 levels than the controls. The HI group showed ventriculomegaly and marked reduction of myelin basic protein immunoreactivities in the WM. T4 (1 mg/kg) treatment after HI markedly attenuated axonal injury, astrocytosis, and microgliosis, and increased preoligodendrocyte survival. In addition, T4 treatment significantly increased myelination and selectively upregulated brain-derived neurotrophic factor expression in the WM, and improved neuromotor deficits after HI. The protective effect of T4 on WM myelination and neuromotor performance after HI was significantly attenuated by TrkB-Fc. Systemic 7,8-dihydroxyflavone treatment ameliorated hypomyelination after HI injury. T4 protects against WM injury at both pathological and functional levels via upregulation of brain-derived neurotrophic factor-TrkB signaling in the immature brain.

  12. Multicompartmental model for iodide, thyroxine, and triiodothyronine metabolism in normal and spontaneously hyperthyroid cats

    Energy Technology Data Exchange (ETDEWEB)

    Hays, M.T.; Broome, M.R.; Turrel, J.M.

    1988-06-01

    A comprehensive multicompartmental kinetic model was developed to account for the distribution and metabolism of simultaneously injected radioactive iodide (iodide*), T3 (T3*), and T4 (T4*) in six normal and seven spontaneously hyperthyroid cats. Data from plasma samples (analyzed by HPLC), urine, feces, and thyroid accumulation were incorporated into the model. The submodels for iodide*, T3*, and T4* all included both a fast and a slow exchange compartment connecting with the plasma compartment. The best-fit iodide* model also included a delay compartment, presumed to be pooling of gastrosalivary secretions. This delay was 62% longer in the hyperthyroid cats than in the euthyroid cats. Unexpectedly, all of the exchange parameters for both T4 and T3 were significantly slowed in hyperthyroidism, possibly because the hyperthyroid cats were older. None of the plasma equivalent volumes of the exchange compartments of iodide*, T3*, or T4* was significantly different in the hyperthyroid cats, although the plasma equivalent volume of the fast T4 exchange compartments were reduced. Secretion of recycled T4* from the thyroid into the plasma T4* compartment was essential to model fit, but its quantity could not be uniquely identified in the absence of multiple thyroid data points. Thyroid secretion of T3* was not detectable. Comparing the fast and slow compartments, there was a shift of T4* deiodination into the fast exchange compartment in hyperthyroidism. Total body mean residence times (MRTs) of iodide* and T3* were not affected by hyperthyroidism, but mean T4* MRT was decreased 23%. Total fractional T4 to T3 conversion was unchanged in hyperthyroidism, although the amount of T3 produced by this route was increased nearly 5-fold because of higher concentrations of donor stable T4.

  13. Multicompartmental model for iodide, thyroxine, and triiodothyronine metabolism in normal and spontaneously hyperthyroid cats

    International Nuclear Information System (INIS)

    Hays, M.T.; Broome, M.R.; Turrel, J.M.

    1988-01-01

    A comprehensive multicompartmental kinetic model was developed to account for the distribution and metabolism of simultaneously injected radioactive iodide (iodide*), T3 (T3*), and T4 (T4*) in six normal and seven spontaneously hyperthyroid cats. Data from plasma samples (analyzed by HPLC), urine, feces, and thyroid accumulation were incorporated into the model. The submodels for iodide*, T3*, and T4* all included both a fast and a slow exchange compartment connecting with the plasma compartment. The best-fit iodide* model also included a delay compartment, presumed to be pooling of gastrosalivary secretions. This delay was 62% longer in the hyperthyroid cats than in the euthyroid cats. Unexpectedly, all of the exchange parameters for both T4 and T3 were significantly slowed in hyperthyroidism, possibly because the hyperthyroid cats were older. None of the plasma equivalent volumes of the exchange compartments of iodide*, T3*, or T4* was significantly different in the hyperthyroid cats, although the plasma equivalent volume of the fast T4 exchange compartments were reduced. Secretion of recycled T4* from the thyroid into the plasma T4* compartment was essential to model fit, but its quantity could not be uniquely identified in the absence of multiple thyroid data points. Thyroid secretion of T3* was not detectable. Comparing the fast and slow compartments, there was a shift of T4* deiodination into the fast exchange compartment in hyperthyroidism. Total body mean residence times (MRTs) of iodide* and T3* were not affected by hyperthyroidism, but mean T4* MRT was decreased 23%. Total fractional T4 to T3 conversion was unchanged in hyperthyroidism, although the amount of T3 produced by this route was increased nearly 5-fold because of higher concentrations of donor stable T4

  14. Effect of thyroidectomy and thyroxine on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced immunotoxicity

    International Nuclear Information System (INIS)

    Pazdernik, T.L.; Rozman, K.K.

    1985-01-01

    Radiothyroidectomy protected against 2,3,7,8-tetrachloro dibenzo-p-dioxin (TCDD)-induced immunotoxicity in rats as assessed by the spleen anti-SRBC plaque-forming cell assay. Thyroxin (T 4 ) replacement therapy partially reversed the effects of thyroidectomy on T 4 and triiodothyronine (T 3 ) serum levels, body weight and immune function as well as restored TCDD-induced immunotoxicity. Thus, hypothyroidism induced by TCDD exposure can be viewed as a protective response of the organism to reduce the insult caused by TCDD

  15. Interlaboratory survey for T3 and T4 assays in Italy: results from a two semester period

    International Nuclear Information System (INIS)

    Pilo, A.; Zucchelli, G.C.; Chiesa, M.R.; Piro, M.A.

    1982-01-01

    The usefulness of external quality control schemes (EQCS) is generally acknowledged in clinical chemistry; these schemes allow not only the evaluation of the between-laboratory variability of the assay under study, but also make it possible the improvement of the analytical performances of the participants laboratories. Recently interlaboratory surveys have been extended to radioimmunoassays. Starting from january 1980, a national EQCS hormone assays was organized in Italy; triiodothyronine (T3) and thyroxine (T4) have been the first assays considered due to their large diffusion

  16. A radioimmunoassay for measurement of thyroxine sulfate

    International Nuclear Information System (INIS)

    Chopra, I.J.; Santini, F.; Hurd, R.E.; Chua Teco, G.N.

    1993-01-01

    A highly sensitive, specific, and reproducible RIA has been developed to measure T 4 sulfate (T 4 S) in ethanol extracts of serum. rT 3 sulfate (rT 3 S) cross-reacted 7.1%, and T 3 S cross-reacted 0.59% in the RIA; T 4 , T 3 , rT 3 and 3,3'-diiodothyronine cross-reacted 0.004% or less. The recovery of nonradioactive T 4 S added to serum averaged 95%. The detection threshold of the RIA was 18 pmol/L. The coefficient of variation averaged 6.9% within an assay and 12% between assays. T 4 S was bound by T 4 -binding globulin and albumin in serum. The free fraction of T 4 S in four normal sera averaged 0.06% compared to a value of 0.03% for T 4 (P 4 S was (mean ± SE) 19 ± 1.2 pmol/L in normal subjects, 33 ± 10 in hyperthyroid patients with Graves disease, 42 ± 15 in hypothyroid patients, 34 ± 6.9 in patients with systematic nonthyroidal illnesses, 21 ± 4.3 in pregnant women at 15-40 weeks gestation, and 245 ± 26 in cord blood sera of newborns; the value in the newborn was significantly different from normal (P 4 S. The T 4 S content of the thyroid gland was less than 1/4000th that of T 4 . We conclude that (1) T 4 S is a normal component of human serum, and its levels are markedly increased in newborn serum and amniotic fluid; and (2) the sulfation pathway plays an important role in the metabolism of T 4 in man. 28 refs., 4 figs., 2 tabs

  17. Effects of triiodothyronine on turnover rate and metabolizing enzymes for thyroxine in thyroidectomized rats.

    Science.gov (United States)

    Nagao, Hidenori; Sasaki, Makoto; Imazu, Tetsuya; Takahashi, Kenjo; Aoki, Hironori; Minato, Kouichi

    2014-10-29

    Previous studies in rats have indicated that surgical thyroidectomy represses turnover of serum thyroxine (T4). However, the mechanism of this process has not been identified. To clarify the mechanism, we studied adaptive variation of metabolic enzymes involved in T4 turnover. We compared serum T4 turnover rates in thyroidectomized (Tx) rats with or without infusion of active thyroid hormone, triiodothyronine (T3). Furthermore, the levels of mRNA expression and activity of the metabolizing enzymes, deiodinase type 1 (D1), type 2 (D2), uridine diphosphate-glucuronosyltransferase (UGT), and sulfotransferase were also compared in several tissues with or without T3 infusion. After the T3 infusion, the turnover rate of serum T4 in Tx rats returned to normal. Although mRNA expression and activity of D1 decreased significantly in both liver and kidneys without T3 infusion, D2 expression and activity increased markedly in the brain, brown adipose tissue, and skeletal muscle. Surprisingly, hepatic UGT mRNA expression and activity in Tx rats increased significantly in comparison with normal rats, and returned to normal after T3 infusion. This study suggests that repression of the disappearance of serum T4 in rats after Tx is a homeostatic response to decreased serum T3 concentrations. Additionally, T4 glucuronide is a storage form of T4, but may also have biological significance. These results suggest strongly that repression of deiodination of T4 by D1 in the liver and kidneys plays a major role in thyroid hormone homeostasis in Tx rats, and that hepatic UGT also plays a key role in this mechanism. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Direct and indirect parameters of free thyroxine. Pt. 2

    International Nuclear Information System (INIS)

    Reiners, C.; Hoffmann, R.; Moll, E.; Baum, K.; Becker, W.; Eilles, C.; Gerhards, W.; Schick, F.; Spiegel, W.; Wiedemann, W.; Boerner, W.

    1983-01-01

    Part II of the study concerning the clinical applicability of direct and indirect parameters for free thyroxine evaluates the diagnostic accuracy of the FT 4 -RIAs ImmoPhase, GammaCoat, Liquisol, Amerlex and LisoPhase in relation to FT 4 index and T 4 /TBG ratio. This comparison of methods is done on a thoroughly classified collection (n = 640) of patients with normal and impaired thyroid function including patients with binding protein anomalies (pregnancy, estrogen-medication, phenytoin therapy, renal protein loss). FT 4 normal ranges of a given kit harmonize well with data of the manufacturers and of the literature. On the other hand, the normal ranges of the various kits are not comparable. The differentiation of euthyroidism from hyper- or hypothyroidism can be made without problems using any of these methods, with the exception of the FT 4 -RIA GammaCoat. As expected, patients with euthyroid goiter show, on the average, slightly lower parameters for FT 4 . In pregnancy all direct and indirect parameters for FT 4 have a tendency to lower values after the first trimester. This trend is most distinct for the T 4 /TBG ratio. A weak negative correlation of FT 4 parameters with basal TSH, which does not exceed the upper normal range, however, can be interpreted in the sense of a relative hypothyroxinemia. Under contraceptive estrogen medication FT 4 parameters do not fall outside the normal range, with the exception of the FT 4 -RIA ImmoPhase assay which yields a significantly increased frequency of high FT 4 levels. (orig./RW) [de

  19. Thyroxine treatment may be useful for subclinical hypothyroidism in patients with female infertility.

    Science.gov (United States)

    Yoshioka, Waka; Amino, Nobuyuki; Ide, Akane; Kang, Shino; Kudo, Takumi; Nishihara, Eijun; Ito, Mitsuru; Nakamura, Hirotoshi; Miyauchi, Akira

    2015-01-01

    Infertile women sometimes associated with subclinical hypothyroidism (SCH). The guidelines of the American Endocrine Society, and American Association of Clinical Endocrinologists and American Thyroid Association recommend treatment with thyroxine (T4) for patients with SCH who want to have children. We examined 69 female infertile patients with SCH and the effects of levothyroxine (l-T4) therapy on pregnancy rates and pregnancy outcomes were observed. Fifty-eight (84.1%) patients successfully conceived during the T4 treatment period (Group A), although 17 patients (29.3%) had miscarriage afterward. The remaining 11 patients continued to be infertile (Group B). The median TSH value in Group A before the T4 treatment was 5.46 μIU/mL (range 3.1-13.3) and this significantly decreased to 1.25 μIU/mL (range 0.02-3.75) during the treatment (ptreatment was 2.8±1.7 years and the duration until pregnancy after the treatment was significantly shorter at 0.9±0.9 years (ptreatment strongly suggest that T4 enhanced fertility in infertile patients with SCH.

  20. Gestational exposure to high perchlorate concentrations in drinking water and neonatal thyroxine levels.

    Science.gov (United States)

    Amitai, Yona; Winston, Gary; Sack, Joseph; Wasser, Janice; Lewis, Matthew; Blount, Benjamin C; Valentin-Blasini, Liza; Fisher, Nirah; Israeli, Avi; Leventhal, Alex

    2007-09-01

    To assess the effect of gestational perchlorate exposure through drinking water on neonatal thyroxine (T(4)). T(4) values were compared among newborns in Ramat Hasharon, Israel, whose mothers resided in suburbs where drinking water contained perchlorate water exclusively (as determined by a telephone interview) were analyzed as a subset. Serum perchlorate levels in blood from donors residing in the area were used as proxy indicators of exposure. Neonatal T(4) values (mean +/- SD) in the very high, high, and low exposure groups were 13.9 +/- 3.8, 13.9 +/- 3.4, and 14.0 +/- 3.5 microg/dL, respectively (p = NS). Serum perchlorate concentrations in blood from donors residing in areas corresponding to these groups were 5.99 +/- 3.89, 1.19 +/- 1.37, and 0.44 +/- 0.55 microg/L, respectively. T(4) levels of neonates with putative gestational exposure to perchlorate in drinking water were not statistically different from controls. This study finds no change in neonatal T(4) levels despite maternal consumption of drinking water that contains perchlorate at levels in excess of the Environmental Protection Agency (EPA) drinking water equivalent level (24.5 microg/L) based on the National Research Council reference dose (RfD) [0.7 microg/(kg.day)]. Therefore the perchlorate RfD is likely to be protective of thyroid function in neonates of mothers with adequate iodide intake.

  1. Unusual ratio between free thyroxine and free triiodothyronine in a long-lived mole-rat species with bimodal ageing.

    Science.gov (United States)

    Henning, Yoshiyuki; Vole, Christiane; Begall, Sabine; Bens, Martin; Broecker-Preuss, Martina; Sahm, Arne; Szafranski, Karol; Burda, Hynek; Dammann, Philip

    2014-01-01

    Ansell's mole-rats (Fukomys anselli) are subterranean, long-lived rodents, which live in eusocial families, where the maximum lifespan of breeders is twice as long as that of non-breeders. Their metabolic rate is significantly lower than expected based on allometry, and their retinae show a high density of S-cone opsins. Both features may indicate naturally low thyroid hormone levels. In the present study, we sequenced several major components of the thyroid hormone pathways and analyzed free and total thyroxine and triiodothyronine in serum samples of breeding and non-breeding F. anselli to examine whether a) their thyroid hormone system shows any peculiarities on the genetic level, b) these animals have lower hormone levels compared to euthyroid rodents (rats and guinea pigs), and c) reproductive status, lifespan and free hormone levels are correlated. Genetic analyses confirmed that Ansell's mole-rats have a conserved thyroid hormone system as known from other mammalian species. Interspecific comparisons revealed that free thyroxine levels of F. anselli were about ten times lower than of guinea pigs and rats, whereas the free triiodothyronine levels, the main biologically active form, did not differ significantly amongst species. The resulting fT4:fT3 ratio is unusual for a mammal and potentially represents a case of natural hypothyroxinemia. Comparisons with total thyroxine levels suggest that mole-rats seem to possess two distinct mechanisms that work hand in hand to downregulate fT4 levels reliably. We could not find any correlation between free hormone levels and reproductive status, gender or weight. Free thyroxine may slightly increase with age, based on sub-significant evidence. Hence, thyroid hormones do not seem to explain the different ageing rates of breeders and non-breeders. Further research is required to investigate the regulatory mechanisms responsible for the unusual proportion of free thyroxine and free triiodothyronine.

  2. Unusual ratio between free thyroxine and free triiodothyronine in a long-lived mole-rat species with bimodal ageing.

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Henning

    Full Text Available Ansell's mole-rats (Fukomys anselli are subterranean, long-lived rodents, which live in eusocial families, where the maximum lifespan of breeders is twice as long as that of non-breeders. Their metabolic rate is significantly lower than expected based on allometry, and their retinae show a high density of S-cone opsins. Both features may indicate naturally low thyroid hormone levels. In the present study, we sequenced several major components of the thyroid hormone pathways and analyzed free and total thyroxine and triiodothyronine in serum samples of breeding and non-breeding F. anselli to examine whether a their thyroid hormone system shows any peculiarities on the genetic level, b these animals have lower hormone levels compared to euthyroid rodents (rats and guinea pigs, and c reproductive status, lifespan and free hormone levels are correlated. Genetic analyses confirmed that Ansell's mole-rats have a conserved thyroid hormone system as known from other mammalian species. Interspecific comparisons revealed that free thyroxine levels of F. anselli were about ten times lower than of guinea pigs and rats, whereas the free triiodothyronine levels, the main biologically active form, did not differ significantly amongst species. The resulting fT4:fT3 ratio is unusual for a mammal and potentially represents a case of natural hypothyroxinemia. Comparisons with total thyroxine levels suggest that mole-rats seem to possess two distinct mechanisms that work hand in hand to downregulate fT4 levels reliably. We could not find any correlation between free hormone levels and reproductive status, gender or weight. Free thyroxine may slightly increase with age, based on sub-significant evidence. Hence, thyroid hormones do not seem to explain the different ageing rates of breeders and non-breeders. Further research is required to investigate the regulatory mechanisms responsible for the unusual proportion of free thyroxine and free triiodothyronine.

  3. Vanishing large ovarian cyst with thyroxine therapy

    OpenAIRE

    Dharmshaktu, Pramila; Kutiyal, Aditya; Dhanwal, Dinesh

    2013-01-01

    Summary A 21-year-old female patient recently diagnosed with severe hypothyroidism was found to have a large ovarian cyst. In view of the large ovarian cyst, she was advised to undergo elective laparotomy in the gynaecology department. She was further evaluated in our medical out-patient department (OPD), and elective surgery was withheld. She was started on thyroxine replacement therapy, and within a period of 4 months, the size of the cyst regressed significantly, thereby improving the cond...

  4. Thyroxine-induced cardiac hypertrophy: influence of adrenergic nervous system versus renin-angiotensin system on myocyte remodeling.

    Science.gov (United States)

    Hu, L W; Benvenuti, L A; Liberti, E A; Carneiro-Ramos, M S; Barreto-Chaves, M L M

    2003-12-01

    The present study assessed the possible involvement of the renin-angiotensin system (RAS) and the sympathetic nervous system (SNS) in thyroxine (T4)-induced cardiac hypertrophy. Hemodynamic parameters, heart weight (HW), ratio of HW to body weight (HW/BW), and myocyte width were evaluated in absence of thyroid hormone (hypothyroidism) and after T4 administration. Male Wistar rats were used. Some were subjected to thyroidectomies, whereas hyperthyroidism was induced in others via daily intraperitoneal injection of T4 (25 or 100 microg x 100 g BW(-1) x day(-1)) for 7 days. In some cases, T4 administration was combined with the angiotensin I-converting enzyme inhibitor enalapril (Ena), with the angiotensin type 1 (AT1) receptor blocker losartan (Los) or with the beta-adrenergic blocker propanolol (Prop). Hemodynamics and morphology were then evaluated. Systolic blood pressure (SBP) was not altered by administration of either T4 alone or T4 in combination with the specific inhibitors. However, SBP decreased significantly in hypothyroid rats. An increased heart rate was seen after administration of either T4 alone or T4 in combination with either Los or Ena. Although the higher dose of T4 significantly increased HW, HW/BW increased in both T4-treated groups. Ena and Prop inhibited the increase in HW or HW/BW in hyperthyroid rats. Morphologically, both T4 dose levels significantly increased myocyte width, an occurrence prevented by RAS or SNS blockers. There was a good correlation between changes in HW/BW and myocyte width. These results indicate that T4-induced cardiac hypertrophy is associated with both the SNS and the RAS.

  5. Elevated serum free thyroxine by thyroxine analog radioimmunoassays in euthyroid patients with familial dysalbuminemic hyperthyroxinemia

    International Nuclear Information System (INIS)

    Rajatanavin, R.; Fournier, L.; DeCosimo, D.; Abreau, C.; Braverman, L.E.

    1982-01-01

    A study was done to ascertain whether the serum free T4 measured by free T4 radioimmunoassay kits would, like equilibrium dialysis, be normal in patients with familial dysalbuminemic hyperthyroxinemia. Five free T4 radioimmunoassay kits were used to measure free T4 in serum samples from 19 patients with familial dysalbuminemic hyperthyroxinemia and 20 healthy volunteers. Values (mean +/- SE) for T4, free T4 index, and free T4 (equilibrium dialysis) in these normal subjects and patients with familial dysalbuminemic hyperthyroxinemia, respectively, were as follows: T4, 8.1 +/- 0.2 and 18.3 +/- 0.7 μg/dL; free T4 index, 3.1 +/- 0.1 and 7.3 +/- 0.3 μg/dL; free T4, 1.4 +/- 0.1 and 1.2 +/- 0.1 ng/dL. The following free T4 radioimmunoassay methods were used: antibody coated microfine silica, microencapsulated antibody, two-step antibody-coated tube, and one-step 125 I-T4 analog (2 kits). The present findings in patients with familial dysalbuminemic hyperthyroxinemia and previous observations in ill euthyroid patients suggest that serum free T4 measured by some radioimmunoassay methods must be interpreted with caution in these two clinical situations

  6. Quality control of radioimmunoassay reagents for T4

    International Nuclear Information System (INIS)

    Wayan Radiatning, S.

    1987-01-01

    Quality control of radioimmunoassay reagents for T4. A program of quality control testing has been carried out for 125 I-T4, T4 standards and T4 antisera. 125 I-labelled T4 has been tested for its specific activity, radiochemical purity using a Sephadex G-25 column, immunological activity, based on the immunological reaction between labelled antigen and excess T4 antibody, and non-specific binding. The useful shelf-life of the labelled compound was determined by monitoring the decrease in radiochemical purity and immunological activity, and the increase in non-specific binding. T4 standards were calibrated by means of T4 RIA kit manufactured by DPC (Diagnostic Products Corporation). A test on parallelism was also performed using hyperthyroid sera. T4 antisera were evaluated with respect to titre, avidity and specifity. The test results on 125 I-T4 show a specific activity varying between 1830-2020 uCi/ug, a radiochemical purity above 90%, an immunological more than 80% and a non-specific binding of less than 5%. The standard curve for T4 was found to coincide well with the standard curve of the DPC kit and parallel with the curve for hyperthyroid sera. The titre of T4 antisera obtained was 1:300, the avidity was about 4.8 x 10 7 and the cross-reaction for T3 was 1.6%. It can be concluded from the experimental results, that the 125 I-T4, T4 standards and T4 antisera prepared meet the requirements for the manufacture of T4 kits. (author). 5 refs.; 14 figs

  7. Preparation of second antibody enhanced coated tubes for radioimmunoassay of triiodothyronine and thyroxine

    International Nuclear Information System (INIS)

    Mehany, N.L.; El-Kolaly, M.T.; Ghonaim, A.; Abdelmouhty, N.R.

    1999-01-01

    The production of high technology RIA reagents with low cost is considered to be one of the important goal of labelled compounds dept., Radioisotope production division, hot labs centre, egyptian atomic energy authority. The development of a direct radioimmunoassay for the measurement of triiodothyronine (T 3 ) and thyroxine (T 4 ) in human serum is described. The coating of polystyrene tubes with affinity purified second antibody (Donkey antisheep antibody, DASS) followed by sheep polyclonal antisera specific for each of T 3 and T 4 was carried out. The stability study of these coated tubes revealed that these tubes could stored for at least one year at 4degree C without any appreciable reduction in binding. The assays were performed by adding 200 MU1 radiolabelled hormones ( 125 I - T 3 or 125 I - T 4 ) to standards, unknown samples or quality controls (50 MU1 10 MU1 for T 3 and T 4 , respectively ) into corresponding assay tubes. The reaction is allowed to proceed at 37degree C for 2h and 1h for T 3 and T 4 respectively. Then the tubes were decanted, washed and counted. Twenty human serum samples of different thyroid disorders were analyzed for T 3 and T 4 using the present systems and with commercially available kits (DOC, coated tubes). The statistical analysis showed good correlations between the results obtained from the present systems and the DPC kits (r = 0.994 and 0.990 for T 3 and T 4 respectively). Hypothyroid, euthyroid and hyperthyroid subjects are reasonably and accurately distinguished using our methods

  8. Effects of thyroxin therapy on different analytes related to obesity and inflammation in dogs with hypothyroidism.

    Science.gov (United States)

    Tvarijonaviciute, A; Jaillardon, L; Cerón, J J; Siliart, B

    2013-04-01

    Hypothyroidism in dogs is accompanied by changes in intermediary metabolism including alterations in bodyweight (BW), insulin resistance, and lipid profile. In this study, changes in selected adipokines (adiponectin, leptin), butyrylcholinesterase (BChE), and acute phase proteins, including C-reactive protein, haptoglobin (Hp) and serum amyloid A (SAA), were studied in dogs with hypothyroidism under thyroxin therapy. Blood samples were collected when hypothyroidism was diagnosed (before treatment) and after treatment with thyroxin. Twenty-eight of 39 dogs exhibited a good therapeutic response (group A), whereas the remainder were considered to have been insufficiently treated (group B). Following treatment, group A dogs demonstrated a statistically significant decrease in canine thyroid stimulating hormone (c-TSH) (P<0.001) and an increase in free thyroxine (fT4) (P<0.001) concentrations, associated with a significant decrease in BW (P<0.05), leptin (P<0.01), and adiponectin, (P<0.001) and an increase in BChE (P<0.01) and Hp (P<0.05). Group B dogs showed no statistically significant changes in c-TSH, but had a significant increase in fT4 (P<0.001) accompanied by a significant decrease in adiponectin (P<0.05) of lower magnitude than group A. No significant changes in the mean circulating levels of APPs were observed in both groups, with the exception of an increase in Hp (P<0.05) in group A. In summary, the successful treatment of hypothyroidism reduces circulating levels of adiponectin and leptin, while increasing BChE activity in dogs. The mean increase in Hp values and decrease in SAA for some of the dogs after treatment warrants further investigation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Changes in plasma low-density lipoprotein (LDL)- and high-density lipoprotein cholesterol in hypo- and hyperthyroid patients are related to changes in free thyroxine, not to polymorphisms in LDL receptor or cholesterol ester transfer protein genes

    NARCIS (Netherlands)

    Diekman, M. J.; Anghelescu, N.; Endert, E.; Bakker, O.; Wiersinga, W. M.

    2000-01-01

    Thyroid function disorders lead to changes in lipoprotein metabolism. Both plasma low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) increase in hypothyroidism and decrease in hyperthyroidism. Changes in LDL-C relate to altered clearance of LDL particles

  10. Acute mania after thyroxin supplementation in hypothyroid state

    Directory of Open Access Journals (Sweden)

    Rohit Verma

    2013-01-01

    Full Text Available The current literature variedly ascribes depressive and manic symptoms to hypo- and hyperthyroid state, respectively, reporting mania in hypothyroidism as an unusual entity. More unusual is precipitation of manic state in hypothyroid subjects after thyroxine supplementation for which studies report otherwise treating manic symptoms in hypothyroid state with thyroxine. We report a case of a patient whose acute mania appears to have been precipitated by thyroxine supplementation in hypothyroidism state. This case underscores the importance of thyroid screening in patients with mood and psychotic disorders, as well as the potency of thyroxine in producing manic symptoms.

  11. T4 thyrotoxicosis: an independent disease or the effect of an alteration in the peripheral metabolism of T4

    International Nuclear Information System (INIS)

    Maciel, R.M.B.; Vieira, J.G.H.; Russo, E.M.K.; Dib, S.A.

    1983-01-01

    Six cases of T 4 thyrotoxicosis were observed in 250 patients with hyperthyroidism. In the 6 episodes, the thyrotoxicosis was associated with severe systemic illness or with the admnistration of propanolol, which blocked the peripheral convertion of T 4 to T 3 . These data indicate that T 4 thyrotoxicosis reflects an alteration in the peripheral metabolism of T 4 produced by systemic illness or drugs. (M.A.C.) [pt

  12. Rapid T4 radioimmunoassay with antibody of Czechoslovak production

    Energy Technology Data Exchange (ETDEWEB)

    Cechacek, Z [MUNZ, Brno (Czechoslovakia) Div. of Nuclear Nedicine

    1978-06-30

    Rapid T4-RIA based on the T4-antibody produced in Institute of Experimental Endocrinology in Bratislava is described. The used T4-antibody was found as suitable preparation for the routine T4-RIA and is comparable to the foreign materials. T4 antibody was obtained by rabbit immunization and supplied as antiserum in a frozen state. It was properly diluted with 0.08M barbital buffer, pH 8.6, containing 0.a5% sodium ethylmercurythiosalicylate and 0.5% BSA.

  13. Polybrominated diphenyl ethers--plasma levels and thyroid status of workers at an electronic recycling facility.

    Science.gov (United States)

    Julander, A; Karlsson, M; Hagström, K; Ohlson, C G; Engwall, M; Bryngelsson, I-L; Westberg, H; van Bavel, B

    2005-08-01

    Personnel working with electronic dismantling are exposed to polybrominated diphenyl ethers (PBDEs), which in animal studies have been shown to alter thyroid homeostasis. The aim of this longitudinal study was to measure plasma level of PBDEs in workers at an electronic recycling facility and to relate these to the workers' thyroid status. PBDEs and three thyroid hormones: triiodothyronine (T(3)), thyroxin (T(4)) and thyroid stimulating hormone (TSH) were repeatedly analysed in plasma from 11 workers during a period of 1.5 years. Plasma levels of PBDEs at start of employment were plasma levels of PBDEs fluctuated during the study period. Due to small changes in thyroid hormone levels it was concluded that no relevant changes were present in relation to PBDE exposure within the workers participating in this study.

  14. Contribution of maternal thyroxine to fetal thyroxine pools in normal rats near term

    International Nuclear Information System (INIS)

    Morreale de Escobar, G.; Calvo, R.; Obregon, M.J.; Escobar Del Rey, F.

    1990-01-01

    Normal dams were equilibrated isotopically with [ 125 I]T4 infused from 11 to 21 days of gestation, at which time maternal and fetal extrathyroidal tissues were obtained to determine their [ 125 I]T4 and T4 contents. The specific activity of the [ 125 I]T4 in the fetal tissues was lower than in maternal T4 pools. The extent of this change allows evaluation of the net contribution of maternal T4 to the fetal extrathyroidal T4 pools. At 21 days of gestation, near term, this represents 17.5 +/- 0.9% of the T4 in fetal tissues, a value considerably higher than previously calculated. The methodological approach was validated in dams given a goitrogen to block fetal thyroid function. The specific activities of the [ 125 I]T4 in maternal and fetal T4 pools were then similar, confirming that in cases of fetal thyroid impairment the T4 in fetal tissues is determined by the maternal contribution. Thus, previous statements that in normal conditions fetal thyroid economy near term is totally independent of maternal thyroid status ought to be reconsidered

  15. Intraindividual variation of triiodothyronine, thyroxine, thyrotropin and thyroxine-binding globulin in fasting serum from healthy men

    International Nuclear Information System (INIS)

    Liappis, N.; Hoffmann, U.; Rao, M.L.

    1986-01-01

    The concentrations of triiodothyronine, thyroxine, thyrotropin and thyroxine-binding globulin were determined in fasting serum from 11 healthy men (age 18-25 years) by radioimmunoassays conducted over a period of 4 weeks on 5 consecutive days per week. The concentrations of thyroxine and thyroxine-binding globulin were very consistent intraindividually, with coefficients of variation of 7.84% and 9.37%, respectively. The triiodothyronine and thyrotropin levels showed significant intraindividual variability with coefficients of variation of 18.38% and 51.85%, respectively. These results point to the type of difficulties encountered in judging serum values, namely intraindividual variations over a given period of time. (orig.) [de

  16. Effect of Propranolol on Thyroxine-Induced Changes in Body Temperature and Metabolism During Exercise in Dogs

    Science.gov (United States)

    Kaciuba-Uscilko, Hanna; Brzezinska, Zofia; Greenleaf, John E.

    1976-01-01

    Effects of thyroxine on temperature and metabolism during exercise were studied in dogs after beta-adrenergic blockade. Dogs performed 60 min treadmill exercise of moderate intensity 5 and 72 h following thyroxine injected s. c. in a single dose of 0.1 mg/kg b.w. Thyroxine increased significantly the lipolytic response to exercise as well as blood lactate (LA) concentrations and rectal temperature (T(sub re)) during exercise as early as 5 h following the hormone administration. The changes became more pronounced 72 h after the injection. At rest T(sub re), blood FFA (free fatty acid) and LA levels in the thyroxine-treated dogs did not differ from the control values, and blood glucose was slightly, but significantly higher. Propranolol given intravenously in a dose of 0.25 mg/kg at 30 min of the exercise performed 72 h following thyroxine injection abolished the plasma FFA rise, and inhibited to a certain extent increases in T(sub re) and blood LA concentrations during the next 30 min of exercise.

  17. Effects of 18 months of L-T4 replacement in women with subclinical hypothyroidism.

    LENUS (Irish Health Repository)

    Adrees, M

    2012-02-01

    CONTEXT: Some of the cardiovascular and renal abnormalities seen in overt hypothyroidism have also been reported in subclinical hypothyroidism (SCH). Short-term L-T4 replacement in SCH improves cardiovascular risk markers and reduces carotid intima-media thickness (CIMT), a surrogate marker of atherosclerosis. The haemodynamic and renal effects of L-T4 replacement in SCH are poorly understood. OBJECTIVES: To compare cardiovascular risk factors and renal variables in women with SCH and normal women. To study the effects of L-T4 replacement in SCH subjects on these variables and on structural and functional changes in common carotid and brachial arteries. DESIGN: Fifty-six women with SCH before and after L-T4 replacement for 18 months and 56 normal women of similar age distribution were studied. Blood Pressure (BP), plasma lipids and homocysteine were measured and renal function evaluated [estimation of glomerular filtration rate (eGFR) using standard equations and measurement of serum Cystatin-C] in women with SCH before and after 18 months of l-T4, and in healthy women. CIMT and endothelial function (using brachial artery ultrasound) were studied before and after L-T4 in a subgroup of women with SCH. RESULTS: Systolic and diastolic BP, total cholesterol, triglyceride, LDL-cholesterol, lipoprotein(a) and homocysteine were greater in SCH (P < 0.05), and following L-T4 replacement decreased (P < 0.05) to levels that no longer differed from normal subjects. Estimated GFR was reduced and serum Cystatin-C increased (P < 0.05) in SCH. These variables also normalized following L-T4. Following L-T4 replacement the carotid artery baseline diameter increased by 7.1% and CIMT decreased by a mean value of 13%, while brachial artery diameter increased basally by 12.5% and following endothelium-dependent vasodilatation by 17.5% (P < 0.05). However, the increment following reactive hyperaemia did not differ before or following L-T4 replacement. CONCLUSION: Normalization of

  18. USEFULNESS OF FREE THYROXINE TO FREE TRIIODOTHYRONINE RATIO FOR DIAGNOSTICS OF VARIOUS TYPES OF HYPERTHYROIDISM

    Directory of Open Access Journals (Sweden)

    Jernej Grmek

    2015-06-01

    Full Text Available Background: Different types of hyperthyroidism are treated differently. The correct diagnosis enables the adequate treatment. Clinical experiences suggest that free thyroxine (fT4 to free triiodothyronine (fT3 ratio is different for different types of hyperthyroidism. Considering the paucity of literature data on the topic our aim was to evaluate the role of the serum fT4 to fT3 (fT4/fT3ratio in diagnostics of various types of hyperthyroidism.Methods: In retrospective clinical study we included 440 consecutive subjects, examined between February and August 2010, 350 females and 90 males aged between 15 and 97 years, among them 225 healthy subjects (HS, 80 patients with Graves' disease (GD, 48 with toxic adenoma (TA, 61 patients with hyperthyroid Hashimoto’s thyroiditis (HHT, 17 with subacute thyroiditis (ST, and 9 patients with iodine-induced hyperthyroidism (IIH. Thyrotropin (TSH, fT4, fT3 and thyroid autoantibodies were measured. The fT4/fT3 ratio was calculated.Results: The fT4/fT3 ratio was significantly different for various disorders causing hyperthyroidism (p<0.001. Compared with the fT4/fT3 ratio in HS (2.86±0.52, the ratio was significantly higher in HHT and ST (3.27±0.72 and 3.31±0.54, respectively, p<0.001 for both. In GD, the fT4/fT3 ratio was the lowest (2.55±0.58 and in IIH the highest (5.13±1.97. Both ratios significantly differed from the ratio in HS (p<0.001 for both and in other hyperthyroid patients (p<0.001 for both. In patients with TA, the fT4/fT3 ratio was similar as in HS (2.85±0.71 (p=0.085.Conclusion: The fT4/fT3 ratio is different in various types of hyperthyroidism and therefore represents a useful tool in the diagnostic procedure.

  19. Urea, Uric Acid, Prolactin and fT4 Concentrations in Aqueous Humor of Keratoconus Patients.

    Science.gov (United States)

    Stachon, Tanja; Stachon, Axel; Hartmann, Ulrike; Seitz, Berthold; Langenbucher, Achim; Szentmáry, Nóra

    2017-06-01

    Keratoconus is a noninflammatory disease of the cornea associated with progressive thinning and conical shape. Metabolic alterations in the urea cycle, with changes in collagen fibril stability, oxidative stress, thyroid hormones and prolactin with regulatory effect on biosynthesis and biomechanical stability of corneal stroma, may all play a role in keratoconus etiology. Our purpose was to determine urea, uric acid, prolactin and free thyroxin (fT4) concentrations in human aqueous humor (hAH) of keratoconus and cataract patients. hAH was collected from 100 keratoconus (penetrating keratoplasty) (41.9 ± 14.9 years, 69 males) and 100 cataract patients (cataract surgery) (71.2 ± 12.4 years, 58 males). Urea, uric acid, prolactin and fT4 concentrations were measured by Siemens clinical chemistry or immunoassay system. For statistical analysis, a generalized linear model (GLM) was used. Urea concentration was 11.88 ± 3.03 mg/dl in keratoconus and 16.44 ± 6.40 mg/dl in cataract patients, uric acid 2.04 ± 0.59 mg/dl in keratoconus and 2.18 ± 0.73 mg/dl in cataract groups. Prolactin concentration was 3.18 ± 0.34 ng/ml in keratoconus and 3.33 ± 0.32 ng/ml in cataract patients, fT4 20.57 ± 4.76 pmol/l in KC and 19.06 ± 3.86 pmol/l in cataract group. Urea concentration was effected through gender (p = 0.039), age (p = 0.001) and diagnosis (p = 0.025). Uric acid concentration was not effected through any of the analyzed parameters (p > 0.056). Prolactin and fT4 concentration were effected only through diagnosis (p = 0.009 and p = 0.006). Urea and prolactin concentrations are decreased, fT4 concentration is increased in aqueous humor of keratoconus patients, and uric acid concentration remains unchanged. Urea concentration in aqueous humor is also increased in older and male patients. Therefore, metabolic disorder and hormonal balance may both have an impact on keratoconus development. Further studies are necessary to assess the specific impact.

  20. The metabolic consequences of thyroxine replacement in adult hypopituitary patients

    DEFF Research Database (Denmark)

    Filipsson Nyström, Helena; Feldt-Rasmussen, Ulla; Kourides, Ione

    2012-01-01

    The metabolic consequences of thyroxine replacement in patients with central hypothyroidism (CH) need to be evaluated. The aim was to examine the outcome of thyroxine replacement in CH. Adult hypopituitary patients (n = 1595) with and without CH from KIMS (Pfizer International Metabolic Database...

  1. Congenital hypothyroidism: influence of disease severity and L-thyroxine treatment on intellectual, motor, and school-associated outcomes in young adults.

    Science.gov (United States)

    Oerbeck, Beate; Sundet, Kjetil; Kase, Bengt F; Heyerdahl, Sonja

    2003-10-01

    To describe intellectual, motor, and school-associated outcome in young adults with early treated congenital hypothyroidism (CH) and to study the association between long-term outcome and CH variables acting at different points in time during early development (CH severity and early L-thyroxine treatment levels [0-6 years]). Neuropsychological tests were administered to all 49 subjects with CH identified during the first 3 years of the Norwegian neonatal screening program (1979-1981) at a mean age of 20 years and to 41 sibling control subjects (mean age: 21 years). The CH group attained significantly lower scores than control subjects on intellectual, motor, and school-associated tests (total IQ: 102.4 [standard deviation: 13] vs 111.4 [standard deviation: 13]). Twelve (24%) of the 49 CH subjects had not completed senior high school, in contrast to 6% of the control subjects. CH severity (pretreatment serum thyroxine [T4]) correlated primarily with motor tests, whereas early L-thyroxine treatment levels were related to verbal IQ and school-associated tests. In multiple regression analysis, initial L-thyroxine dose (beta = 0.32) and mean serum T4 level during the second year (beta = 0.48) predicted Verbal IQ, whereas mean serum T4 level during the second year (beta = 0.44) predicted Arithmetic. Long-term outcome revealed enduring cognitive and motor deficits in young adults with CH relative to control subjects. Verbal functions and Arithmetic were associated with L-thyroxine treatment variables, suggesting that more optimal treatment might be possible. Motor outcome was associated with CH severity, indicating a prenatal effect.

  2. Thyroxine clearance in rats within the first month after the single whole-body {gamma} - irradiation at a dose of 10Gy

    Energy Technology Data Exchange (ETDEWEB)

    Pryadko, Kirill A. [Institute of Radiobiology, National Academy of Sciences, Minsk (Belarus)

    2002-07-01

    The effects of acute whole-body {gamma} -irradiation at a dose of 10 Gy on thyroxine (T{sub 4}) plasma clearance rate (PCR) and thyroidal and blood T4 concentration ([T{sub 4}]) were examined within one month after exposure. The PCR values were measured using the bolus injection, single-compartmental approach. To eliminate the influence of radiation-induced anorexia animals were fasting for two days before the pharmacokinetic experiments. Hormone concentrations in blood and in thyroid tissue were measured by RIA. Throughout the observation period, PCR was elevated in irradiated rats with maximum at day 4 after exposure (0.56{+-}0.04 vs. 0.36{+-}0.03 ml/h100 gbw, P<0.001). [T{sub 4}] in blood was not significantly different from that in control animals. Thyroidal [T{sub 4}] was significantly decreased in irradiated animals 4 days after exposure (151.8{+-}21.7 vs. 258.8{+-}29.9 pmol/mg protein, P<0.01) and gradually increased after day 9. 10 Gy {gamma} -irradiation causes the intensification of T{sub 4} metabolism without the pronounced changes in concentration. Presumably, at early terms the rising local demand in O{sub 4} can not be compensated with the existing level of production. Alterations in the intensity of T{sub 4} metabolism are evident at least one month after exposure but they may not be detected without taking into account kinetic data.

  3. Diagnostic Evaluation of Effective Thyroxine Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myung Chul; Choi, Sang Jae; Ro, Heung Kyu; Lee, Hong Kyu; Koh, Chang Soon; Lee, Mun Ho [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1975-09-15

    The purpose of the present study is to evaluate the diagnostic value of the ETR test as compared to other thyroid function tests in normal persons, patients with thyroid disorders and patients with alterations of thyroxine-binding proteins. The ETR values were obtained from 35 cases as normal control, 63 hyperthyroid patients, 56 euthyroid patients, 23 hypothyroid patients, 10 pregnant women, 5 women taking oral contraceptive medication, 8 liver cirrhosis patients and 4 nephrotic syndrome patients. The results obtained were as follows. 1) The mean value of ETR obtained from the normal controls was 0.99+-0.06. 2) The mean ETR values of various thyroid states were 1.25+-0.16 in hyperthyroidism, 0.99+-0.08 in euthyroidism and 0.82+-0.05 in hypothyroidism and significant difference was found between these groups. 3) Seven out of 63 hyperthyroid patients (11.1%) and 2 out of 23 hypothyroid patients (8.7%) had ETR values within normal range and among the 56 euthyroid patients 6 (10.7%) had ETR values outside normal range, so the diagnostic compatibility of ETR was 89.4% in thyroid diseases. 4) Even though the ETR value was well correlated with {sup 131}I-thyroid uptake rate, serum T{sub 3} resin uptake rate and serum T{sub 4}, a high positive correlation was found (r=0.79) between ETR and T{sub 7}. 5) The mean ETR values from patients with alteration in TBG binding capacity were 0.99+-0.05 in pregnant women, 0.98+-0.04 in women with oral contraceptive medication, 1.04+-0.09 in liver cirrhosis patients and 0.94+-0.02 in nephrotic syndrome patients and most of them (85.2%) had ETR values within normal range. Our results, therefore, suggests that the ETR estimation does offer the simplest and most reliable single procedure for the screening and diagnosis of various thyroid diseases as a indirect indicator of serum-free thyroxine concentration without essential influence of changes in the thyroxine-binding proteins in serum.

  4. Control survey of normal reference ranges adopted for serum thyroxine binding globulin, thyroxine, triiodothyronine in Japan

    International Nuclear Information System (INIS)

    Sugisaki, Hajime; Kameyama, Mayumi; Shibata, Kyoko

    1985-01-01

    A survey using questionnaires was made on 152 facilities from July through September 1984 to examine normal reference ranges of serum thyroxine binding globulin (TBG), thyroxine (TT 4 ), and triiodothyronine (TT 3 ). Normal reference ranges of TBG were in good agreement with each other, with the exception of four facilities showing high upper limits. An average value of the upper and lower limits in 83 facilities was 13.7 +- 1.9 μg/ml; and the standard deviation was 28.6 +- 2.8 μg/ml. Differences (approximately 10 %) in coefficient of variation were comparable to those (5.7-9.6 %) obtained from the previous survey. There were approximately 10 % differences in coefficient of variation for both TT 4 and TT 3 . (Namekawa, K.)

  5. Rethinking the biological relationships of the thyroid hormones, l-thyroxine and 3,5,3'-triiodothyronine.

    Science.gov (United States)

    Maher, Stacey K; Wojnarowicz, Pola; Ichu, Taka-Aki; Veldhoen, Nik; Lu, Linghong; Lesperance, Mary; Propper, Catherine R; Helbing, Caren C

    2016-06-01

    Thyroid hormones (THs), l-thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are essential for vertebrate growth and development. Classically, T4 is 5'-deiodinated to the active hormone, T3, in target tissues which then binds nuclear TH receptors (TRs) and regulates gene transcription. However, it is possible that T4 acts directly on target tissues. Frog metamorphosis is a powerful TR-dependent model for studying TH action. Premetamorphic Rana (Lithobates) catesbeiana tadpoles were injected with 0.1-50 T3 or 0.5-250T4pmol/gbodyweight to account for their 5-fold difference in biological activity and the mRNA profiles in six tissues from well-characterized TH-responsive genes were evaluated after 48h using quantitative real time polymerase chain reaction. 5'-deiodinase-poor tissues should produce superimposable dose-response curves if T4 does not require conversion to T3. This was the case in lung and tail fin; the latter tissue recapitulating these responses in organ culture. 5'-deiodinase-rich tissues should convert T4 to T3. Because T3 has a higher affinity to TRs, a 5-fold higher T4 dose compared to T3 should produce greater transcript induction. This was observed in the brain and for most intestinal transcripts. However, some gene transcripts in the intestine and all transcripts in the back skin produced superimposable response curves suggesting that a direct mode of T4 action is plausible in these tissues. While the liver showed results consistent with its 5'-deiodinase-poor status, we found evidence of an alternate, non-genomic mechanism for two gene transcripts. Therefore, mechanisms not requiring T4 conversion to T3 may play a far greater role than previously thought. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Family of autocatalytic group I introns in bacteriophage T4

    International Nuclear Information System (INIS)

    Shub, D.A.; Xu, M.Q.; Gott, J.M.; Zeeh, A.; Wilson, L.D.

    1987-01-01

    The discovery of an intron in phage T4 encouraged the authors to look for additional group I introns in the T4 genome. Further examples would permit sequence and structural comparisons that might lend insight into their evolutionary origin. Additionally, they hoped that their locations within the T4 genome would infer a possible regulatory function in prokaryotic gene expression. They took advantage of the fact that, since G is added to the 5' end of the intron, autocatalytic group I introns could be specifically labeled in vitro for use as probes for DNA blotting experiments. If Group I introns were in more than just the td gene, multiple RNA species should be labeled when total RNA is extracted from T4-infected cells and incubated with [α- 32 P]GTP in vitro. When used as a probe for a Southern blot of T4 DNA, this RNA should hybridize to several DNA bands

  7. Effects of Hypothyroidism and Exogenous Thyroxine on ...

    African Journals Online (AJOL)

    olayemitoyin

    made hyperthyroid by giving 100pg/kg.bw of T4 for five weeks, while the other ten ... hormones and as a regulator of the hormone activity. Excess of or deficiency in thyroid hormone alters the function and metabolism of the gastrointestinal tract.

  8. Cold-increase in brown fat thyroxine 5'-monodeiodinase is attenuated in Zucker obese rat

    International Nuclear Information System (INIS)

    Wu, S.Y.; Stern, J.S.; Fisher, D.A.; Glick, Z.

    1987-01-01

    In this study the authors examined the possibility that the reduced brown adipose tissue (BAT) thermogenesis in the Zucker obese rat may result from a limited capacity for enzymic conversion of thyroxine (T 4 ) to triiodothyronine (T 3 ) in BAT. A total of 34 lean and obese rats, ∼4 mo old were divided into three treatment groups: group 1 (5 lean and 6 obese) was fed Purina rat chow for 21 days, and group two (5 lean and 6 obese) was fed a cafeteria diet for 21 days, and groups 3 (6 lean and 6 obese) was fed Purina rat chow and maintained in the cold (8 +/- 1 0 C) for 7 days. Activity of T 4 5'-deiodinase was determined as the rate of T 3 production from added T 4 under controlled in vitro conditions. Serum T 4 and T 3 were determined by radioimmunoassay. The rate of T 4 -to-T 3 conversion in BAT was similar in the lean and obese rats maintained at room temperature, whether fed rat chow or a cafeteria diet. However, expressed per scapular BAT depot, lean rats exposed to cold displayed about a fivefold increase in BAT T 3 production whereas only a small increase was observed in the cold-exposed obese rats. Serum T 3 levels tended to be reduced in the Zucker obese rats. The data indicate a reduced capacity for T 3 production of Zucker rat BAT exposed to cold. This defect may account for the reduced tolerance of the obese animals to cold, but it does not account for their reduced diet-induced BAT thermogenesis

  9. A simple unifying procedure for radioimmunoassay of thyroxine, triiodothyronine and reverse triiodothyronine in unextracted serum

    International Nuclear Information System (INIS)

    Slebodzinski, A.B.; Nowak, G.; Zamyslowska, H.

    1980-01-01

    A simple unifying procedure for radioimmunoassay (RIA) of thyroxine, T 4 , triiodothyronine, T 3 , and reverse-triiodothyronine, rT 3 , in unextracted serum has been developed. In the method 8-anilino-naphthalene sulfonic acid, sodium salicylate and barbital were used as inhibitors of iodothyronine binding to proteins of serum and charcoal for separation of antibody-bound and free hormone fractions. For statistical evaluation and quality control of the results the assay data were analyzed after logit/log transformation. In this way, a reasonable linearization of the standard curve was achieved. The lower limit of detection of T 4 was 35 pg and for triiodothyronine (T 3 plus rT 3 ) 7.5 pg. The intraassay variability averaged from 5-7%. Corresponding betweenassay coefficient of variation was from 11-13%. The recovery of added hormone to the hormone-free serum was near 100%, and the index of precision (lambda) below 0.1. The useable range of hormone determination was found to be from 0.5 μg to 15 μg T 4 and from 15 to 200 ng T 3 or rT 3 per dl serum. Using this unifying procedure one person can perform about 120 determinations per day. After logit/log transformation of the input data and linearization of the standard curve, the statistical analysis and data processing can be easily performed by a suitable RIA programme for a top desk calculator. (author)

  10. Clinical significance of the measurements of serum free thyroxine and free triiodothyronine concentrations

    International Nuclear Information System (INIS)

    Kubota, Ken; Sasaki, Norio; Takaku, Fumimaro; Uchimura, Hidemasa

    1988-01-01

    A commercially available ''DPC'' radioimmunoassay kit was used to study the serum concentrations of free triiodothyronine (FT3) and free thyroxine (FT4) in a series of 189 patients with various thyroid diseases and 120 healthy controls. The basal serum concentrations of FT3 and FT4 in normal controls ranged from 0.98 to 2.04 ng/dl and from 1.43 to 3.66 pg/ml, respectively. All untreated patients with Graves' disease had abnormally high FT3 and FT4 values, indicating the discrimination between hyperthyroid and normal subjects. A decreased ratio of FT4 to FT3 was observed in patients managed with antithyroid drugs. In diagnosing hypothyroidism, ''DPC'' FT4 kits were more sensitive than ''DPC'' TT4 and ''Amerlex'' FT4 kits. In the case of non-thyroid diseases, FT4 and FT3 values, as well as total T4 and total T3, were normal or decreased, with the exception of occasionally unknown high values. The interference of thyroxine binding globulin abnormablity was successfully eliminated by using new versions of ''DPC'' kits. (Namekawa, K.)

  11. Simultaneous Study of Thyroxine and Triiodothyronine ({sup 125}I-T{sub 4} and {sup 131}I T{sub 3}) Metabolism: Diagnostic Value in Thyroid and Metabolic Diseases; Etude Simultanee du Metabolisme de la Thyroxine et de la Triiodothyronine ({sup 125}I-T{sub 4} - {sup 131}I T{sub 3}) - Interet Diagnostique dans les Maladies Thyroiediennes et Metaboliques

    Energy Technology Data Exchange (ETDEWEB)

    Jaffiol, C.; Pastorello, R.; Baldet, L.; Robin, M.; Mirouze, J. [Clinique des Maladies Metaboliques et Endocriniennes, Montpellier (France)

    1971-02-15

    The characteristic parameters of the metabolism of the two thyroid hormones (biological half-life, renewal rate, dilution space, pool, quantity of hormones consumed daily) are studied after the simultaneous intravenous injection of 200 {mu}Ci of {sup 125}I-T4 and {sup 131}I-T3, The plasma samples are first subjected to chromatography so as to separate the hormonal fraction from the iodides. Studies are then made on 10 control subjects, three subjects with hyperthyroidism, six with hypothyroidism, 41 diabetics, two subjects with nephrotic syndromes and five with renal insufficiency. In the case of the subjects with thyroid diseases, analysis of the results,reveals that, relative to the control subjects, there is a significantly reduced daily consumption of hormones on the part of the subjects with hypothyroidism and a significantly enhanced consumption on the part of those with hyperthyroidism. A parallel study of the thyroxine binding capacity of TBG and TBPA suggests an interpretation of these differences, which appear to be inversely proportional to the amount of thyroxine bound to the carrier proteins of the plasma. This test is of particular practical value in the case of subjects saturated with an organo-iodized contrast substance and in atypical forms of the disease where it is difficult to interpret the results of the classical biological tests. In alimentary diabetes, insulin therapy increases the amount of T4 and (even more so) T3 consumed daily, whereas hypoglycaemic sulphamides do not appear to have any effect. In the subjects with nephrotic syndromes, the T4 renewal rate is enhanced while the renal clearance is very high, in contrast to that of T3, which is not as closely bound to the proteins. In renal insufficiency, the renewal rate of T4 is greatly reduced while its dilution space and pool are enhanced. These results indicate the value of this technique both in the diagnosis of thyroid diseases and in the physiopathological interpretation of

  12. Quality characteristics of chemicals for the radioimmunoassay of thyroxine and thyrotropin

    International Nuclear Information System (INIS)

    Verdeja I, C.E.

    1994-01-01

    Radioimmunoassay is a form of saturation analysis in which the test material competes with labelled antigen for a limited amount of antibody, the amount of label displaced being a measure of the antigen in the test sample. In this country, the kits for Radioimmunoassay (RIA) are imported, and this increase the cost of it. Because this lack of production, the National Institute of Nuclear Research (ININ) has developed RIA's kits for the thyroxine (T 4 ), Thyrotropin (TSH) and Triyodotironine (T 3 ) hormones. This work presents the conclusions of the test recommended by the WHO. The quality test were: recuperation, cross reactions, basic parameters, intra and inter assay variations, sensibility and others. The results show that the RIA's kits of the ININ have a good behavior and can be use in the clinical laboratory. (Author)

  13. Re-initiation repair in bacteriophage T4

    International Nuclear Information System (INIS)

    Cupido, M.

    1981-01-01

    Irradiation of bacteriophage T4 with ultraviolet light induces the formation of pyrimidine dimers in its DNA. These dimers hamper replication of DNA and, to a lesser extent, transcription of DNA after its infection of bacteria. A number of pathways enable phage T4 to multiply dimer-containing DNA. One of these pathways has been named replication repair and is described in this thesis. The properties of two phage strains, unable to perform replication repair, have been studied to obtain a picture of the repair process. The mutations in these strains that affect replication repair have been located on the genomic map of T4. (Auth.)

  14. Total and free thyroxine and triiodothyronine: measurement discrepancies, particularly in inpatients.

    Science.gov (United States)

    Jonklaas, Jacqueline; Sathasivam, Anpalakan; Wang, Hong; Gu, Jianghong; Burman, Kenneth D; Soldin, Steven J

    2014-09-01

    We compared the performance of tandem mass spectrometry versus immunoassay for measuring thyroid hormones in a diverse group of inpatients and outpatients. Thyroxine (T4), triiodothyronine (T3), free thyroxine (FT4), and free triiodothyronine (FT3) were measured by liquid chromatography tandem mass spectrometry and immunoassay in 100 patients and the two assays were compared. T4 and T3 values measured by the two different assays correlated well with each other (r=0.91-0.95). However, the correlation was less good at the extremes (r=0.51-0.75). FT4 and FT3 concentrations measured by the two assays correlated less well with each other (r=0.75 and 0.50 respectively). The studied analytes had poor inverse correlation with the log-transformed TSH values (r=-0.22-0.51) in the population as a whole. The strongest correlations were seen in the groups of outpatients (r=-0.25-0.61). The weakest degree of correlation was noted in the inpatient group, with many correlations actually being positive. The worst between-assay correlation was demonstrated at low and high hormone concentrations, in the very concentration ranges where accurate assay performance is typically most clinically important. Based on the lesser susceptibility of mass spectrometry to interferences from conditions such as binding protein abnormalities, we speculate that mass spectrometry better reflects the clinical situation. In this mixed population of inpatients and outpatients, we also note failure of assays to conform to the anticipated inverse linear relationship between thyroid hormones and log-transformed TSH. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  15. Selenium derivatives of thyroxine and tri-iodothyronine

    International Nuclear Information System (INIS)

    Cree, G.M.

    1980-01-01

    Novel selenium derivatives of thyroxine and tri-iodothyronine are described. They preferably contain at least one 75 Se atom. The compounds are useful in dual isotope assays of thyroid function. (U.K.)

  16. Retinal S-opsin dominance in Ansell's mole-rats (Fukomys anselli) is a consequence of naturally low serum thyroxine.

    Science.gov (United States)

    Henning, Yoshiyuki; Mladěnková, Nella; Burda, Hynek; Szafranski, Karol; Begall, Sabine

    2018-03-12

    Mammals usually possess a majority of medium-wavelength sensitive (M-) and a minority of short-wavelength sensitive (S-) opsins in the retina, enabling dichromatic vision. Unexpectedly, subterranean rodents from the genus Fukomys exhibit an S-opsin majority, which is exceptional among mammals, albeit with no apparent adaptive value. Because thyroid hormones (THs) are pivotal for M-opsin expression and metabolic rate regulation, we have, for the first time, manipulated TH levels in the Ansell's mole-rat (Fukomys anselli) using osmotic pumps. In Ansell's mole-rats, the TH thyroxine (T4) is naturally low, likely as an adaptation to the harsh subterranean ecological conditions by keeping resting metabolic rate (RMR) low. We measured gene expression levels in the eye, RMR, and body mass (BM) in TH-treated animals. T4 treatment increased both, S- and M-opsin expression, albeit M-opsin expression at a higher degree. However, this plasticity was only given in animals up to approximately 2.5 years. Mass-specific RMR was not affected following T4 treatment, although BM decreased. Furthermore, the T4 inactivation rate is naturally higher in F. anselli compared to laboratory rodents. This is the first experimental evidence that the S-opsin majority in Ansell's mole-rats is a side effect of low T4, which is downregulated to keep RMR low.

  17. Association between l-thyroxine treatment, GH deficiency, and radiological vertebral fractures in patients with adult-onset hypopituitarism.

    Science.gov (United States)

    Mazziotti, G; Mormando, M; Cristiano, A; Bianchi, A; Porcelli, T; Giampietro, A; Maffezzoni, F; Serra, V; De Marinis, L; Giustina, A

    2014-06-01

    In this study, we aimed at evaluating the association between radiological vertebral fractures and levo-thyroxine (l-T4) replacement doses in adult patients with hypopituitarism. Cross-sectional study. We studied 74 adult hypopituitary patients (males, 43; females, 31; mean age, 57 years; and range, 23-79) with central hypothyroidism treated with l-T4 (median daily dose: 1.1  μg/kg). All patients also had severe GH deficiency (GHD) and 38 of them were replaced with recombinant GH. Vertebral fractures were assessed by a quantitative morphometric analysis performed on thoracic and lumbar spine lateral X-ray. Radiological vertebral fractures were found in 23 patients (31.1%) in association with untreated GHD (P=0.02), higher serum free T4 levels (P=0.03), a higher daily dose of l-T4 (P=0.005), and a longer duration of hypopituitarism (P=0.05). When GHD was treated, the prevalence of vertebral fractures was more frequent (P=0.03) in patients receiving high l-T4 doses (third tertile: >1.35  μg/kg per day) as compared with patients who were treated with lower drug doses (first tertile: hypopituitarism. © 2014 European Society of Endocrinology.

  18. Disruption of thyroid hormone homeostasis in Ugt1a-deficient Gunn rats by microsomal enzyme inducers is not due to enhanced thyroxine glucuronidation

    International Nuclear Information System (INIS)

    Richardson, Terrilyn A.; Klaassen, Curtis D.

    2010-01-01

    Microsomal enzyme inducers (MEI) that increase UDP-glucuronosyltransferases (UGTs) are thought to increase glucuronidation of thyroxine (T 4 ), thus reducing serum T 4 , and subsequently increasing thyroid stimulating hormone (TSH). Ugt1a1 and Ugt1a6 mediate T 4 glucuronidation. Therefore, this experiment determined the involvement of Ugt1a enzymes in increased T 4 glucuronidation, decreased serum T 4 , and increased TSH after MEI treatment. Male Wistar and Ugt1a-deficient Wistar (Gunn) rats were fed a control diet or diet containing pregnenolone-16α-carbonitrile (PCN; 800 ppm), 3-methylcholanthrene (3-MC; 200 ppm), or Aroclor 1254 (PCB; 100 ppm) for 7 days. Serum T 4 , triiodothyronine (T 3 ), and TSH concentrations, hepatic T 4 /T 3 glucuronidation, and thyroid histology and follicular cell proliferation were investigated. PCN, 3-MC, and PCB treatments decreased serum T 4 , whereas serum T 3 was maintained in both Gunn and Wistar rats (except for PCB treatment). TSH was increased in Wistar and Gunn rats after PCN (130 and 277%) or PCB treatment (72 and 60%). T 4 glucuronidation in Wistar rats was increased after PCN (298%), 3-MC (85%), and PCB (450%), but was extremely low in Gunn rats, and unchanged after MEI. T 3 glucuronidation was increased after PCN (121%) or PCB (58%) in Wistar rats, but only PCN increased T 3 glucuronidation in Gunn rats (43%). PCN treatment induced thyroid morphological changes and increased follicular cell proliferation in both strains. These data demonstrate that T 4 glucuronidation cannot be increased in Ugt1a-deficient Gunn rats. Thus, the decrease in serum T 4 , increase in TSH, and increase in thyroid cell proliferation after MEI are not dependent on increased T 4 glucuronidation, and cannot be attributed to Ugt1a enzymes.

  19. Vanishing large ovarian cyst with thyroxine therapy.

    Science.gov (United States)

    Dharmshaktu, Pramila; Kutiyal, Aditya; Dhanwal, Dinesh

    2013-01-01

    A 21-year-old female patient recently diagnosed with severe hypothyroidism was found to have a large ovarian cyst. In view of the large ovarian cyst, she was advised to undergo elective laparotomy in the gynaecology department. She was further evaluated in our medical out-patient department (OPD), and elective surgery was withheld. She was started on thyroxine replacement therapy, and within a period of 4 months, the size of the cyst regressed significantly, thereby improving the condition of the patient significantly. This case report highlights the rare and often missed association between hypothyroidism and ovarian cysts. Although very rare, profound hypothyroidism that can cause ovarian cysts in an adult should always be kept in the differential diagnosis to avoid unnecessary ovarian surgery. Hypothyroidism should be considered in the differential diagnosis of adult females presenting with multicystic ovarian tumours.Adequate thyroid hormone replacement therapy can prevent these patients from undergoing unnecessary and catastrophic ovarian resection.Surgical excision should be considered only when adequate thyroid replacement therapy fails to resolve ovarian enlargement.In younger women with ovarian cysts, it is also desirable to avoid unnecessary surgery so as to not compromise fertility in the future.

  20. Genetic diversity among five T4-like bacteriophages

    Directory of Open Access Journals (Sweden)

    Bertrand Claire

    2006-05-01

    Full Text Available Abstract Background Bacteriophages are an important repository of genetic diversity. As one of the major constituents of terrestrial biomass, they exert profound effects on the earth's ecology and microbial evolution by mediating horizontal gene transfer between bacteria and controlling their growth. Only limited genomic sequence data are currently available for phages but even this reveals an overwhelming diversity in their gene sequences and genomes. The contribution of the T4-like phages to this overall phage diversity is difficult to assess, since only a few examples of complete genome sequence exist for these phages. Our analysis of five T4-like genomes represents half of the known T4-like genomes in GenBank. Results Here, we have examined in detail the genetic diversity of the genomes of five relatives of bacteriophage T4: the Escherichia coli phages RB43, RB49 and RB69, the Aeromonas salmonicida phage 44RR2.8t (or 44RR and the Aeromonas hydrophila phage Aeh1. Our data define a core set of conserved genes common to these genomes as well as hundreds of additional open reading frames (ORFs that are nonconserved. Although some of these ORFs resemble known genes from bacterial hosts or other phages, most show no significant similarity to any known sequence in the databases. The five genomes analyzed here all have similarities in gene regulation to T4. Sequence motifs resembling T4 early and late consensus promoters were observed in all five genomes. In contrast, only two of these genomes, RB69 and 44RR, showed similarities to T4 middle-mode promoter sequences and to the T4 motA gene product required for their recognition. In addition, we observed that each phage differed in the number and assortment of putative genes encoding host-like metabolic enzymes, tRNA species, and homing endonucleases. Conclusion Our observations suggest that evolution of the T4-like phages has drawn on a highly diverged pool of genes in the microbial world. The T4

  1. Utilizing mass spectrometry imaging to map the thyroid hormones triiodothyronine and thyroxine in Xenopus tropicalis tadpoles.

    Science.gov (United States)

    Goto-Inoue, Naoko; Sato, Tomohiko; Morisasa, Mizuki; Kashiwagi, Akihiko; Kashiwagi, Keiko; Sugiura, Yuki; Sugiyama, Eiji; Suematsu, Makoto; Mori, Tsukasa

    2018-02-01

    Thyroid hormones are not only responsible for thermogenesis and energy metabolism in animals, but also have an important role in cell differentiation and development. Amphibian metamorphosis provides an excellent model for studying the remodeling of the body. This metamorphic organ remodeling is induced by thyroid hormones, and a larval body is thus converted into an adult one. The matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry (MS) imaging technology is expected to be a suitable tool for investigating small bioreactive molecules. The present study describes the distribution of the thyroid hormones, i.e., triiodothyronine (T3) and thyroxine (T4) and their inactive form reverse T3 (rT3) in Xenopus tropicalis tadpoles using two different types of imaging techniques, MS/MS and Fourier transform (FT)-MS imaging. As a result of MS/MS imaging, we demonstrated that T3 was mainly distributed in the gills. T4 was faintly localized in the eyes, inner gills, and intestine during metamorphosis. The intensity of T3 in the gills and the intensity of T4 in the body fluids were increased during metamorphosis. Moreover, the localization of the inactive form rT3 was demonstrated to be separate from T3, namely in the intestine and muscles. In addition, FT-MS imaging could utilize simultaneous imaging including thyroid hormone. This is the first report to demonstrate the molecular distribution of thyroid hormones themselves and to discriminate T3, T4, and rT3 in animal tissues.

  2. Seasonal variations in TSH serum levels in athyreotic patients under L-thyroxine replacement monotherapy.

    Science.gov (United States)

    Gullo, Damiano; Latina, Adele; Frasca, Francesco; Squatrito, Sebastiano; Belfiore, Antonino; Vigneri, Riccardo

    2017-08-01

    Whether serum TSH undergoes seasonal fluctuations in euthyroid and hypothyroid residents of temperate climates is controversial. Monthly TSH and thyroid hormone levels were cross-sectionally analysed in a large cohort of euthyroid subjects (n=11 806) and L-thyroxine (L-T4)-treated athyreotic patients (n=3 934). Moreover, in a small group (n=119) of athyreotic patients treated with an unchanged dosage of L-T4 monotherapy, hormones were measured both in the coldest and in the hottest seasons of the same year (longitudinal study). No seasonal hormone change was observed in the euthyroid subjects except for a small FT3 increase in winter (+2.9%, P<.001). In contrast, the L-T4-treated athyreotic patients had significantly higher serum TSH values in the cold season when the FT4 values were significantly lower. The differences were more notable in the longitudinal series (TSH, 0.80 vs. 0.20 mU/L and FT4, 16.3 vs. 17.8 pmol/L in December-March vs. June-September, respectively). In these patients also serum FT3 values significantly decreased in winter (in the longitudinal series, 3.80 in winter vs 4.07 pmol/L in summer). Regression analysis showed that in athyreotic subjects, a greater FT4 change is required to obtain a TSH change similar to that of euthyroid controls and that this effect is more pronounced in the summer. Athyreotic patients undergoing L-T4 monotherapy have abnormal seasonal variations in TSH. These changes are secondary to the FT4 and FT3 serum decreases in winter, which occur in spite of the constant treatment. The underlying mechanisms are unclear, but in some cases, these changes may be clinically relevant. © 2017 John Wiley & Sons Ltd.

  3. The development of T3-RIA, T4-RIA and TSH-IRMA for in vitro testing of thyroid function

    International Nuclear Information System (INIS)

    Borza, V.; Neacsu, G.; Chariton, Despina

    1998-01-01

    Thyroxine (T 4 ) and triiodothyronine (T 3 ) are two principal thyroid hormones; the release of this hormones and control of different stages of their synthesis are performed by thyrotropin (TSH), secreted by pituitary gland. Also, T 3 and T 4 exert negative feed-back on the pituitary, inhibiting the release of TSH. The measurement of T 3 , T 4 content in un-extracted serum, correlated with TSH values are useful results for investigating the pituitary-thyroid axis. This paper describes radioimmunological procedures for the measurement of T 3 and T 4 using as separation method of the bound and free radiolabeled antigen, the precipitation of antigen-antibody complex by polyethyleneglycol (PEG). Antisera against T 3 , T 4 were produced by immunizing sheep with conjugates of the hormones and bovine albumin; T 3 and T 4 standards were made in horse serum free of these hormones. Binding of T 3 and T 4 to TBG in serum was inhibited by addition of 8-aniline-1-naphthalene-sulfonic acid (ANS). The separation of antigen-antibody complex was carried out using 25.5% PEG 6000. In order to develop a simple T 3 solid phase radioimmunoassay, in this paper the immobilization of anti-T 3 antibodies on polystyrene tubes is presented. The best results were obtained with an exposure time of anti-T 3 antibodies (diluted in buffer solution, pH 8.4-8.6) of 40 h at 4 o C. Also, in this study the preparation of 125 I labeled monoclonal antibody (Mab)-anti-TSH is described, which will be used as a component of a TSH-IRMA kit; this kit is to be realized in our department. 125 I - Mab anti-TSH has the following characteristics: specific activity = 20 - 24 μCi/μg and radioactive concentration ≅ 25 μCi/ml; also, the immunological properties of tracer were verified. The major results of this activity is that the total dependence on important kits will be eliminated and also, the costs will be reduced. (authors)

  4. Mercury exposure associated with altered plasma thyroid hormones in the declining western pond turtle (Emys marmorata) from California mountain streams

    Science.gov (United States)

    Meyer, Erik; Eagles-Smith, Collin A.; Sparling, Donald; Blumenshine, Steve

    2014-01-01

    Mercury (Hg) is a global threat to wildlife health that can impair many physiological processes. Mercury has well-documented endocrine activity; however, little work on the effects of Hg on the thyroid hormones triiodothyronine (T3) and thyroxine (T4) in aquatic wildlife exists despite the fact that it is a sensitive endpoint of contaminant exposure. An emerging body of evidence points to the toxicological susceptibility of aquatic reptiles to Hg exposure. We examined the endocrine disrupting potential of Hg in the western pond turtle (Emys marmorata), a long-lived reptile that is in decline throughout California and the Pacific Northwest. We measured total Hg (THg) concentrations in red blood cells (RBCs) and plasma T3 and T4 of turtles from several locations in California that have been impacted by historic gold mining. Across all turtles from all sites, the geometric mean and standard error THg concentration was 0.805 ± 0.025 μg/g dry weight. Sampling region and mass were the strongest determinants of RBC THg. Relationships between RBC THg and T3 and T4 were consistent with Hg-induced disruption of T4 deiodination, a mechanism of toxicity that may cause excess T4 levels and depressed concentrations of biologically active T3.

  5. Mercury exposure associated with altered plasma thyroid hormones in the declining western pond turtle (Emys marmorata) from California mountain streams.

    Science.gov (United States)

    Meyer, Erik; Eagles-Smith, Collin A; Sparling, Donald; Blumenshine, Steve

    2014-01-01

    Mercury (Hg) is a global threat to wildlife health that can impair many physiological processes. Mercury has well-documented endocrine activity; however, little work on the effects of Hg on the thyroid hormones triiodothyronine (T3) and thyroxine (T4) in aquatic wildlife exists despite the fact that it is a sensitive endpoint of contaminant exposure. An emerging body of evidence points to the toxicological susceptibility of aquatic reptiles to Hg exposure. We examined the endocrine disrupting potential of Hg in the western pond turtle (Emys marmorata), a long-lived reptile that is in decline throughout California and the Pacific Northwest. We measured total Hg (THg) concentrations in red blood cells (RBCs) and plasma T3 and T4 of turtles from several locations in California that have been impacted by historic gold mining. Across all turtles from all sites, the geometric mean and standard error THg concentration was 0.805 ± 0.025 μg/g dry weight. Sampling region and mass were the strongest determinants of RBC THg. Relationships between RBC THg and T3 and T4 were consistent with Hg-induced disruption of T4 deiodination, a mechanism of toxicity that may cause excess T4 levels and depressed concentrations of biologically active T3.

  6. Effects of larval-juvenile treatment with perchlorate and co-treatment with thyroxine on zebrafish sex ratios

    Science.gov (United States)

    Mukhi, S.; Torres, L.; Patino, R.

    2007-01-01

    The objective of this study was to determine the effect of larval-juvenile exposure to perchlorate, a thyroid hormone synthesis inhibitor, on the establishment of gonadal sex ratios in zebrafish. Zebrafish were exposed to untreated water or water containing perchlorate at 100 or 250 ppm for a period of 30 days starting at 3 days postfertilization (dpf). Recovery treatments consisted of a combination of perchlorate and exogenous thyroxine (T4; 10 nM). Thyroid histology was assessed at the end of the treatment period (33 dpf), and gonadal histology and sex ratios were determined in fish that were allowed an additional 10-day period of growth in untreated water. As expected, exposure to perchlorate caused changes in thyroid histology consistent with hypothyroidism and these effects were reversed by co-treatment with exogenous T4. Perchlorate did not affect fish survival but co-treatment with T4 induced higher mortality. However, relative to the corresponding perchlorate concentration, co-treatment with T4 caused increased mortality only at a perchlorate concentration of 100 ppm. Perchlorate alone or in the presence of T4 suppressed body length at 43 dpf relative to control values. Perchlorate exposure skewed the sex ratio toward female in a concentration-dependent manner, and co-treatment with T4 not only blocked the feminizing effect of perchlorate but also overcompensated by skewing the sex ratio towards male. Moreover, co-treatment with T4 advanced the onset of spermatogenesis in males. There was no clear association between sex ratios and larval survival or growth. We conclude that endogenous thyroid hormone plays a role in the establishment of gonadal sex phenotype during early development in zebrafish. ?? 2006 Elsevier Inc. All rights reserved.

  7. Original Research: Metabolic alterations from early life thyroxine replacement therapy in male Ames dwarf mice are transient.

    Science.gov (United States)

    Darcy, Justin; Fang, Yimin; Hill, Cristal M; McFadden, Sam; Sun, Liou Y; Bartke, Andrzej

    2016-10-01

    Ames dwarf mice are exceptionally long-lived due to a Prop1 loss of function mutation resulting in deficiency of growth hormone, thyroid-stimulating hormone and prolactin. Deficiency in thyroid-stimulating hormone and growth hormone leads to greatly reduced levels of circulating thyroid hormones and insulin-like growth factor 1, as well as a reduction in insulin secretion. Early life growth hormone replacement therapy in Ames dwarf mice significantly shortens their longevity, while early life thyroxine (T4) replacement therapy does not. Possible mechanisms by which early life growth hormone replacement therapy shortens longevity include deleterious effects on glucose homeostasis and energy metabolism, which are long lasting. A mechanism explaining why early life T4 replacement therapy does not shorten longevity remains elusive. Here, we look for a possible explanation as to why early life T4 replacement therapy does not impact longevity of Ames dwarf mice. We found that early life T4 replacement therapy increased body weight and advanced the age of sexual maturation. We also find that early life T4 replacement therapy does not impact glucose tolerance or insulin sensitivity, and any deleterious effects on oxygen consumption, respiratory quotient and heat production are transient. Lastly, we find that early life T4 replacement therapy has long-lasting effects on bone mineral density and bone mineral content. We suggest that the transient effects on energy metabolism and lack of effects on glucose homeostasis are the reasons why there is no shortening of longevity after early life T4 replacement therapy in Ames dwarf mice. © 2016 by the Society for Experimental Biology and Medicine.

  8. Introns in the genome of bacteriophage T4

    International Nuclear Information System (INIS)

    Gott, J.M.

    1987-01-01

    RNA from T4-infected cells yields multiple end-labeled species when incubated with [α- 32 P]GTP under self-splicing conditions. One of these corresponds to the previously characterized intron from the T4 td gene and, as shown in this work, the others represent additional group I introns in T4. Two loci distinct from the td gene were found to hybridize to the mixed GTP-labeled T4 RNA probe. These were mapped to the unlinked genes nrdB and sunY. Cloned DNA from the nrdB region that contained the intron was shown to generate characteristic group I splice products with RNA synthesized in vivo or in vitro. The splice junction of the nrdB gene was determined and the nature of the RNA reaction products characterized. In vivo expression of the nrdB gene and the open reading frame within the intron was studied using in-frame lacZ fusions and primer extension analyses. The data suggest that expression of the intron open reading frame is highly regulated during T4 infection. Possible regulatory mechanisms are discussed

  9. Nonsense mutants in the bacteriophage T4D v gene

    Energy Technology Data Exchange (ETDEWEB)

    Minderhout, L van; Grimbergen, J; Groot, B de [Rijksuniversiteit Leiden (Netherlands). Lab. voor Stralengenetica en Chemische Mutagenese; Cohen (J.A.) Instituut voor Radiopathologie en Stralenbescherming, Leiden (Netherlands))

    1975-09-01

    Ten UV-sensitive mutants of T4D with the v phenotype were isolated. Of these ten mutants, two are amber and two opal. In UV curves and in photoreactivation and multiplicity reactivation experiments the nonsense mutants show the v phenotype in su/sup -/ hosts and almost the T4/sup +/ phenotype in su/sup +/ hosts. The mutations are located between rl and e and are alleles of v/sub 1/. In crosses with irradiated and non-irradiated phages the recombinant frequency is not reduced by uvs5. Amber uvs5 propagated in CR63 su/sup +/ is with B su/sup -/ just as sensitive to UV as uvs5 propagated in B su/sup -/, which permits the conclusion that the capsid of T4 phage particles does not contain the v gene product.

  10. The effect of life-long thyroxine treatment and physical activity on bone mineral density in young adult women with congenital hypothyroidism

    NARCIS (Netherlands)

    Kempers, M. J. E.; Vulsma, T.; Wiedijk, B. M.; de Vijlder, J. J. M.; van Eck-Smit, B. L. F.; Verberne, H. J.

    2006-01-01

    OBJECTIVE: Normalization of plasma thyrotropin in T4-supplemented patients with thyroidal congenital hypothyroidism (CH) requires elevated plasma FT4-concentrations compared to patients with acquired thyroidal hypothyroidism. We investigated bone mineral density (BMD) in patients with CH. PATIENTS

  11. Effects of thyroxine and dexamethasone on rat submandibular glands

    International Nuclear Information System (INIS)

    Sagulin, G.B.; Roomans, G.M.

    1989-01-01

    Glucocorticoids and thyroxine are known to have a marked effect on the flow rate and protein composition of rat parotid saliva in hormonally intact animals. In the present study, the effects of a one-week treatment of male rats with dexamethasone and thyroxine were studied by electron microscopy and x-ray micro-analysis, and by measurement of the flow rate and determination of the chemical composition of pilocarpine-induced submandibular saliva. Thyroxine had the most extensive effects on the submandibular gland. The acinar cells were enlarged and filled with mucus; the cellular calcium concentration was significantly increased. The flow rate of the submandibular saliva was significantly reduced compared with that in saline-injected control animals. Thyroxine caused an increase in the concentrations of protein, total calcium, and potassium in the saliva. Dexamethasone had no significant effects on gland ultrastructure or on the elemental composition of the acinar cells; flow rate was not affected, but the concentrations of protein, calcium, and potassium were significantly increased. The effects of dexamethasone and thyroxine on the flow rate and protein composition of pilocarpine-induced rat submandibular saliva differ from those reported earlier for rat parotid saliva after simultaneous stimulation with pilocarpine and isoproterenol

  12. Measurement for serum thyroxine-binding globulin (TBG) and its clinical assessment in diagnosis of thyroid states

    International Nuclear Information System (INIS)

    Imamura, Rikiyo; Yoshimasa, Yasunao; Hamada, Satoshi

    1979-01-01

    Serum levels of thyroxine (T 4 )-binding globulin (TBG) were determined by a radioimmunoassay using cellulose-linked antibody to TBG. Values obtained in healthy young adults averaged 1.62 +- 0.25 (SD) mg/100 ml, and no significant difference was detected between males and females. The TBG levels remained within the normal limit in hyperthyroidism while they were significantly increased in hypothyroidism. Interestingly enough, TBG levels were significantly elevated in chronic thyroidities with no overt hypothyroidism. In normal pregnancy, TBG was increased slightly in the first trimester, and markedly in the second and third trimesters. In one case of congenital TBG deficiency, no immunoreactive TBG was detected. It was demonstrated, further, that an inverse relationship (r = -0.7593) existed between the TBG level and serum triiodothyronine uptake index, and that a direct relation (r = +0.6557) was present between the TBG level and T 4 in sera from normal subjects and pregnancy. Ratios of T 4 /TBG were markedly increased in hyperthyroidism, and decreased in hypothyroidism, showing no overlap with the normal subjects, whereas they were below the normal limit in half the cases in the second and third trimesters of pregnancy. The radioimmunoassay for TBG was useful in evaluating hypothyroid states, because it could differentiate the increase in T 4 associated with elevated TBG from hyperthyroidism. (author)

  13. Effect of combination therapy with thyroxine (T4) and 3,5,3'-triiodothyronine versus T4 monotherapy in patients with hypothyroidism, a double-blind, randomised cross-over study

    DEFF Research Database (Denmark)

    Nygaard, Birte; Jensen, Ebbe Winther; Kvetny, Jan

    2009-01-01

    BACKGROUND: Treatment of hypothyroidism with 3,5,3'-triiodothyronine (T(3)) is controversial. A recent meta-analysis concludes that no evidence is present in favour of using T(3). However, the analysis included a mixture of different patient groups and dose-regimens. OBJECTIVE: To compare the eff...

  14. Incorporation of T4 bacteriophage in electrospun fibres.

    Science.gov (United States)

    Korehei, R; Kadla, J

    2013-05-01

    Antibacterial food packaging materials, such as bacteriophage-activated electrospun fibrous mats, may address concerns triggered by waves of bacterial food contamination. To address this, we investigated several efficient methods for incorporating T4 bacteriophage into electrospun fibrous mats. The incorporation of T4 bacteriophage using simple suspension electrospinning led to more than five orders of magnitude decrease in bacteriophage activity. To better maintain bacteriophage viability, emulsion electrospinning was developed where the T4 bacteriophage was pre-encapsulated in an alginate reservoir via an emulsification process and subsequently electrospun into fibres. This resulted in an increase in bacteriophage viability, but there was still two orders of magnitude drop in activity. Using a coaxial electrospinning process, full bacteriophage activity could be maintained. In this process, a core/shell fibre structure was formed with the T4 bacteriophage being directly incorporated into the fibre core. The core/shell fibre encapsulated bacteriophage exhibited full bacteriophage viability after storing for several weeks at +4°C. Coaxial electrospinning was shown to be capable of encapsulating bacteriophages with high loading capacity, high viability and long storage time. These results are significant in the context of controlling and preventing bacterial infections in perishable foods during storage. © 2013 The Society for Applied Microbiology.

  15. Clinical and evolutive aspects of nasopharyngeal T4 NO

    International Nuclear Information System (INIS)

    Maalej, M.; Bouaouina, N.; Benna, F.; Frikha, H.; Jallouli, M.; Ellouze, R.; Ben Romdhane, K.; Cammoun, M.; Ben Attia, R.; Daoud, J.

    1995-01-01

    Nasopharyngeal carcinoma (NPC) is the primary cancer of the head and neck localizations in the Salah Azaiz Institute (Tunisia). From 1970 to 1987, 80 patients with histologically proven T4 NO NPC, were treated with exclusive radiation (70-75 Gy to the primary lesion and 50-55 Gy to cervical lymph nodes). The T4 NO represents 7% of all NPC and 16% of the T4 treated in our Institute. Ninety percent of the patients are over 20 years old with a mean age of 52 years. The sex-ration was 4: 1. Extension to the brain was observed in 55% of the cases. Local control was 70% at 2 months after the end of irradiation. The actuarial survival at 5 years was 47%. Distant metastasis represent 13% (30% for all NPC). The main failure of treatment was local recurrence. The T4 NO is probably a particular entity concerning the age, the response to radiotherapy and the low rate of distant metastasis. (authors). 18 refs., 5 figs

  16. Seymour Benzer and T4 rII

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 13; Issue 10. Seymour Benzer and T4 rII - Running the Map into the Ground. R Jayaraman. General Article Volume 13 Issue 10 October 2008 pp 898-908. Fulltext. Click here to view fulltext PDF. Permanent link:

  17. Structure and assembly of bacteriophage T4 head

    Directory of Open Access Journals (Sweden)

    Black Lindsay W

    2010-12-01

    Full Text Available Abstract The bacteriophage T4 capsid is an elongated icosahedron, 120 nm long and 86 nm wide, and is built with three essential proteins; gp23*, which forms the hexagonal capsid lattice, gp24*, which forms pentamers at eleven of the twelve vertices, and gp20, which forms the unique dodecameric portal vertex through which DNA enters during packaging and exits during infection. The past twenty years of research has greatly elevated the understanding of phage T4 head assembly and DNA packaging. The atomic structure of gp24 has been determined. A structural model built for gp23 using its similarity to gp24 showed that the phage T4 major capsid protein has the same fold as that found in phage HK97 and several other icosahedral bacteriophages. Folding of gp23 requires the assistance of two chaperones, the E. coli chaperone GroEL and the phage coded gp23-specific chaperone, gp31. The capsid also contains two non-essential outer capsid proteins, Hoc and Soc, which decorate the capsid surface. The structure of Soc shows two capsid binding sites which, through binding to adjacent gp23 subunits, reinforce the capsid structure. Hoc and Soc have been extensively used in bipartite peptide display libraries and to display pathogen antigens including those from HIV, Neisseria meningitides, Bacillus anthracis, and FMDV. The structure of Ip1*, one of the components of the core, has been determined, which provided insights on how IPs protect T4 genome against the E. coli nucleases that degrade hydroxymethylated and glycosylated T4 DNA. Extensive mutagenesis combined with the atomic structures of the DNA packaging/terminase proteins gp16 and gp17 elucidated the ATPase and nuclease functional motifs involved in DNA translocation and headful DNA cutting. Cryo-EM structure of the T4 packaging machine showed a pentameric motor assembled with gp17 subunits on the portal vertex. Single molecule optical tweezers and fluorescence studies showed that the T4 motor packages

  18. Concepts for the assay of unbound thyroxine (FT4) and thyroxine binding globulin (TBG)

    International Nuclear Information System (INIS)

    Odstrchel, G.; Hertl, W.; Ward, F.B.; Travis, K.; Lindner, R.E.; Mason, R.D.

    1977-01-01

    Two new concepts for the assay of thyroid related substances are presented. One assay (FT 4 ) is based on a kinetic measurement of T 4 as it desorbs from binder proteins onto solid-phase T 4 antibody. This reaction can be described by a second order rate equation; r = k (IMA) (FT 4 ). The assay is rapid (2 hours) and gives good agreement (sigma = 0.92) with equilibrium dialysis and a normal range of 0.9 - 2.3 ng/dl. This assay uses a small sample size (25 μl) and is unaffected by drugs such as aspirin and dilantin. Pregnant and estrogen treated women gave normal FT 4 values. A new method for the measurement of functionally active TEG is also presented. In this case the labeled T 4 is partitioned between bovine serum albumin and the patient's samples. The complex is then removed from solution by solid-phase anti-TBG. A curve remiscent of an immunoradiometric assay is obtained. The assay has a sensitivity of 4 μg/ml and is unaffected by aspirin, dilantin or the patient's T 4 concentrations. Correlation with 'rocket' electrophoresis is 0.90. The normal range was 20 +- 7 μg/ml with pregnant women giving values greater than 30 μg/ml. Five hereditary deficient patients gave a value equivalent to zero TBG concentration. (orig.) [de

  19. Scottish immunoassay support service quality control scheme for thyroxine, triiodothyronine, and digoxin assays: analysis of first 18 months' experience

    International Nuclear Information System (INIS)

    Ratcliffe, W.A.; Logue, F.C.; Ratcliffe, J.G.

    1978-01-01

    Initial experience of the Scottish Immunoassay Support Service Quality Control scheme for thyroxin(T4), triiodothyronine (T3), and digoxin is analysed. For T4, radioimmunoassay (RIA) methods gave values close to the all-method mean. Competitive protein binding (CPB) kits gave values significantly higher (by 12%) in one and lower (by 10%) in another, probably due to the extraction of interfering substances such as non-esterified fatty acids or thyroid hormone binding proteins. The range of between-batch precision of individual laboratories was 10.8-47.5% (mean 17.8%) over the clinically relevant range. It was particularly poor at levels below the lower limit of the normal range. For T3 RIA, kit methods gave significantly higher values than independent methods although recovery of exogenous T3 was approximately quantitative with both. Cross reaction of T4 in T3 assays was insignificant. The range of between-batch precision for individual laboratories was 11.4-35.5% (mean 21.9%), and was poorest at levels of 1 nmol/l or less. For digoxin RIA, Lanoxitest γ gave significantly higher values than other methods, and over-recovered exogenous digoxin. The range of between-batch precision was 13.8-35.2% (mean 21.6%), and was poorest at levels of 1 nmol/l or less. The distribution of liquid human serum specimens at ambient temperature was satisfactory for quality control of T4, T3, and digoxin RIA but not for T4 by the Thyopac 4 method. Ox serum was unsuitable for certain T4 RIA methods. (author)

  20. Radioimmunological determination of total thyroxine in the serum

    Energy Technology Data Exchange (ETDEWEB)

    Premachandra, Bhartur

    1975-09-04

    A radioimmunological method to determine total thyroxine in a serum sample is described. The method is as follows: trichloracetic acid and sodium hydroxide are mixed with the sample; radioactive thyroxine is added to the mixture, which is left to reach equilibrium then placed in contact with a resin sponge consisting of a polyurethane foam with intercommunicating cells containing a strongly basic anion exchange resin; the mixture and the resin sponge are incubated, the initial radioactivity of the mixture and resin sponge combination is measured with an appropriate detection system, then the resin sponge is removed from the mixture, washed and its residual radioactivity measured.

  1. Radioimmunological determination of total thyroxine in the serum

    International Nuclear Information System (INIS)

    Premachandra, Bhartur.

    1975-01-01

    A radioimmunological method to determine total thyroxine in a serum sample is described. The method is as follows: trichloracetic acid and sodium hydroxide are mixed with the sample; radioactive thyroxine is added to the mixture, which is left to reach equilibrium then placed in contact with a resin sponge consisting of a polyurethane foam with intercommunicating cells containing a strongly basic anion exchange resin; the mixture and the resin sponge are incubated, the initial radioactivity of the mixture and resin sponge combination is measured with an appropriate detection system, then the resin sponge is removed from the mixture, washed and its residual radioactivity measured [fr

  2. Effects of thyroxine on the migration of hippocampal neurons in newborn rat exposed to HTO

    International Nuclear Information System (INIS)

    Cai Erpeng; Qiu Jun; Wang Yongsheng; Wu Cuiping; Yao Xiaobo; Wang Mingming

    2012-01-01

    Objective: To explore the effect of thyroxine (TH) on the migration of hippocampal neurons in newborn rat exposed to tritiated water (HTO). Methods: The hippocampal neurons from neonatal rats were primarily cultured, 7 days later, randomly divided into control group, HTO group, TH group and HTO + TH group (3.7 × 10 5 Bq/ml HTO and 0.3 μg/ml TH were simultaneously added). After 24 h, the distance of neuronal migration was measured with Leica AF 6000, the expressions of BDNF and Reelin mRNA in neurons were analyzed with reverse transcription polymerase chain reaction (RT-PCR), the expression of β-tubulin protein in neurons was assayed with Western blot and immunocytochemical staining. Results: Compared with control group, the expression of Reelin mRNA, BDNF mRNA and β-tubulin in HTO group were significantly reduced (t=5.80, 5.48, 5.47, P<0.01), but those in HTO + TH group and TH group were obviously increased (t=7.75, 12.06, 13.65, P<0.01; t=4.34, 5.47, 5.65, P<0.01) and higher than that in HTO group (t=2.92, 10.32, 8.76, P<0.01; t=18.07, 20.55, 40.13, P<0.01). Accordingly, the neuronal migration distance in HTO group was much shorter than that in control (t=8.62, P<0.01), and in HTO + TH group and TH group was far longer than that in control (t=7.64, 4.93, P<0.01). Moreover, the neuronal migration distance in HTO + TH group was notably elongated in comparison with that in HTO group (t=11.32, 12.31, P<0.01). Conclusions: Thyroxine may promote the migration of hippocampal neurons in newborn rat exposed to HTO. (authors)

  3. Effect of Thyroxin Treatment on Carotid Intima-Media Thickness (CIMT) Reduction in Patients with Subclinical Hypothyroidism (SCH): a Meta-Analysis of Clinical Trials.

    Science.gov (United States)

    Aziz, Muhammad; Kandimalla, Yugandhar; Machavarapu, Archana; Saxena, Anshul; Das, Sankalp; Younus, Adnan; Nguyen, Michelle; Malik, Rehan; Anugula, Dixitha; Latif, Muhammad A; Humayun, Choudhry; Khan, Idrees M; Adus, Ali; Rasool, Aisha; Veledar, Emir; Nasir, Khurram

    2017-07-01

    Research shows that subclinical hypothyroidism (SCH) is related to an increased carotid intima-media thickness (CIMT), a surrogate marker of subclinical cardiovascular disease (CVD). It is controversial whether or not SCH should be treated to reduce CVD morbidity and mortality. This meta-analysis aimed to determine whether SCH is associated with an increase in CIMT as compared to Euthyroidism (EU) and whether thyroxin (T4) treatment in SCH can reverse the change in CIMT. Two independent reviewers conducted an extensive database research up to December 2016. A total of 12 clinical trials discussed the effect of Thyroxin on CIMT values at pre- and post-treatment in subjects with SCH. CIMT was significantly higher among SCH (n=280) as compared to EU controls (n=263) at baseline; the pooled weighted mean difference (WMD) of CIMT was 0.44 mm [95% confidence interval (CI) 0.14, 0.74], p=0.004; I 2 =65%. After treatment with thyroxin in subjects with SCH (n=314), there was a statistically significant decrease in CIMT from pre- to post-treatment; the pooled WMD of CIMT decrease was [WMD -0.32; 95% CI (-0.47, -0.16), p=<0.0001; I 2 =2%], and it was no longer different from EU controls [WMD 0.13 mm; 95% CI (-0.04, 0.30); p=0.14; I 2 =27%]. The total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL) were higher in SCH as compared to EU controls and decreased significantly after treatment with thyroxin. This meta-analysis shows that thyroxin therapy in subjects with SCH significantly decreases CIMT and improves lipid profile, modifiable CVD risk factors. Thyroid hormone replacement in subjects with SCH may play a role in slowing down or preventing the progression of atherosclerosis.

  4. Simulation of Post-Thyroidectomy Treatment Alternatives for Triiodothyronine or Thyroxine Replacement in Pediatric Thyroid Cancer Patients

    Science.gov (United States)

    Ben-Shachar, Rotem; Huang, Stephen A.; DiStefano, Joseph J.

    2012-01-01

    Background As in adults, thyroidectomy in pediatric patients with differentiated thyroid cancer is often followed by 131I remnant ablation. A standard protocol is to give normalizing oral thyroxine (T4) or triiodothyronine (T3) after surgery and then withdraw it for 2 to 6 weeks. Thyroid remnants or metastases are treated most effectively when serum thyrotropin (TSH) is high, but prolonged withdrawals should be avoided to minimize hypothyroid morbidity. Methods A published feedback control system model of adult human thyroid hormone regulation was modified for children using pediatric T4 kinetic data. The child model was developed from data for patients ranging from 3 to 9 years old. We simulated a range of T4 and T3 replacement protocols for children, exploring alternative regimens for minimizing the withdrawal period, while maintaining normal or suppressed TSH during replacement. The results are presented with the intent of providing a quantitative basis to guide further studies of pediatric treatment options. Replacement was simulated for up to 3 weeks post-thyroidectomy, followed by various withdrawal periods. T4 vs. T3 replacement, remnant size, dose size, and dose frequency were tested for effects on the time for TSH to reach 25 mU/L (withdrawal period). Results For both T3 and T4 replacement, higher doses were associated with longer withdrawal periods. T3 replacement yielded shorter withdrawal periods than T4 replacement (up to 3.5 days versus 7–10 days). Higher than normal serum T3 concentrations were required to normalize or suppress TSH during T3 monotherapy, but not T4 monotherapy. Larger remnant sizes resulted in longer withdrawal periods if T4 replacement was used, but had little effect for T3 replacement. Conclusions T3 replacement yielded withdrawal periods about half those for T4 replacement. Higher than normal hormone levels under T3 monotherapy can be partially alleviated by more frequent, smaller doses (e.g., twice a day). LT4 may be the

  5. Use of chromatography tubes in triiodothyronine and thyroxine ria

    International Nuclear Information System (INIS)

    Inbar, D.; Tamir, Y.; Derfler, S.; Feingers, J.; Wagner, D.

    1980-01-01

    Simple, convenient radioimmunoassay for total triiodothyronine and total thyroxine in human serum are described. Ascending dry column chromatography is used to separate the free and antibody-bound hormone. The method allows for separation by absorption, without centrifugation. The use of test tubes containing pre-measured quantities of lyophilized radioactive reagent obviates unnecessary handling of radioactive solutions. (Auth.)

  6. Serum-thyroxine levels in microwave-exposed rats

    International Nuclear Information System (INIS)

    Lu, S.T.; Lebda, N.; Michaelson, S.M.; Pettit, S.

    1985-01-01

    The nature of the response of the thyroid gland in animals exposed to microwave irradiation is controversial. Animal experimentation has contributed to the controversy because both increased and decreased thyroid functions have been reported. The thyroxine concentration in rats as representative of thyroid function in animals exposed to 2.45-GHz, 120-Hz amplitude-modulated microwaves has been studied. These studies covered a long time span; rats from two commercial sources (BS and CR) were used and subjected to different numbers of exposures, and therefore these data were evaluated for their stability. Two factors could influence in the result significantly, i.e., source of animal and number of sham exposures. Rats used in the 2-hr exposures were from two different commercial sources; rats from CR had a higher (but normal) thyroxine concentration than did rats from BS. Therefore the data of these animals were separated by commercial source for reevaluation. Instead of increased thyroxine concentration in rats exposed at 25, 30, and 40 mW/cm 2 , changes were not noted in any microwave-exposed rats. The influence of sham exposure revealed that appropriate concurrent control and specification of animal source are needed in longitudinal studies. Furthermore, statistical procedures used can greatly influence the conclusions. Thus the specificity of changes in thyroxine concentration in rats exposed to microwaves because of its sporadic occurrence and because of inconsistencies among experiments was doubted

  7. Preparation of standards of triiodothyronine, thyroxine and thyrotropin

    International Nuclear Information System (INIS)

    Lavalley E, C.; Delgado S, B.; Ruiz J, A.; Zambrano A, F.

    1991-10-01

    The standards preparation requires of certain basic principles, some of which are described in this work, which was made with the purpose of establishing the most appropriate conditions for the preparation of standards of triiodothyronine, thyroxine and thyrotropin to be used in radioimmunoanalysis essays. The diverse standards show a balanced displacement, that which is observed in the graphs presented in this work. (Author)

  8. T4 genes in the marine ecosystem: studies of the T4-like cyanophages and their role in marine ecology

    Directory of Open Access Journals (Sweden)

    Millard Andrew D

    2010-10-01

    Full Text Available Abstract From genomic sequencing it has become apparent that the marine cyanomyoviruses capable of infecting strains of unicellular cyanobacteria assigned to the genera Synechococcus and Prochlorococcus are not only morphologically similar to T4, but are also genetically related, typically sharing some 40-48 genes. The large majority of these common genes are the same in all marine cyanomyoviruses so far characterized. Given the fundamental physiological differences between marine unicellular cyanobacteria and heterotrophic hosts of T4-like phages it is not surprising that the study of cyanomyoviruses has revealed novel and fascinating facets of the phage-host relationship. One of the most interesting features of the marine cyanomyoviruses is their possession of a number of genes that are clearly of host origin such as those involved in photosynthesis, like the psbA gene that encodes a core component of the photosystem II reaction centre. Other host-derived genes encode enzymes involved in carbon metabolism, phosphate acquisition and ppGpp metabolism. The impact of these host-derived genes on phage fitness has still largely to be assessed and represents one of the most important topics in the study of this group of T4-like phages in the laboratory. However, these phages are also of considerable environmental significance by virtue of their impact on key contributors to oceanic primary production and the true extent and nature of this impact has still to be accurately assessed.

  9. Development of a simple method for the immobilization of anti-thyroxine antibody on polystyrene tubes for use in the measurement of total thyroxine in serum

    International Nuclear Information System (INIS)

    Rani Gnanasekar; Shalaka Paradkar; Vijay Kadwad; Ketaki Bapat; Grace Samuel; Sachdev, S.S.; Sivaprasad, N.

    2015-01-01

    We describe a simple method for the immobilisation of anti-thyroxine antibody on to the surface of polystyrene tubes and a simple assay format for the quantitative estimation of total thyroxine in serum. The immobilisation of anti-thyroxine antibody was achieved through passive adsorption of normal rabbit gamma globulin and anti-rabbit antibody raised in goat, as immune bridges. This procedure ensured minimum utilisation of primary and secondary antibody as neat sera without precipitation or affinity purification. The developed assay system using these antibody coated tubes covers a range of 0-240 ng/mL of thyroxine with intra and inter assay variations of less than 10 %. (author)

  10. Higher Thyroid-Stimulating Hormone, Triiodothyronine and Thyroxine Values Are Associated with Better Outcome in Acute Liver Failure.

    Science.gov (United States)

    Anastasiou, Olympia; Sydor, Svenja; Sowa, Jan-Peter; Manka, Paul; Katsounas, Antonios; Syn, Wing-Kin; Führer, Dagmar; Gieseler, Robert K; Bechmann, Lars P; Gerken, Guido; Moeller, Lars C; Canbay, Ali

    2015-01-01

    Changes in thyroid hormone levels, mostly as non-thyroidal illness syndrome (NTIS), have been described in many diseases. However, the relationship between acute liver failure (ALF) and thyroid hormone levels has not yet been clarified. The present study evaluates potential correlations of select thyroid functional parameters with ALF. 84 consecutively recruited ALF patients were grouped according to the outcome of ALF (spontaneous recovery: SR; transplantation or death: NSR). TSH, free thyroxine (fT4), free triiodothyronine (fT3), T4, and T3 were determined. More than 50% of patients with ALF presented with abnormal thyroid parameters. These patients had greater risk for an adverse outcome than euthyroid patients. SR patients had significantly higher TSH, T4, and T3 concentrations than NSR patients. Albumin concentrations were significantly higher in SR than in NSR. In vitro T3 treatment was not able to rescue primary human hepatocytes from acetaminophen induced changes in mRNA expression. In patients with ALF, TSH and total thyroid hormone levels differed significantly between SR patients and NSR patients. This might be related to diminished liver-derived transport proteins, such as albumin, in more severe forms of ALF. Thyroid parameters may serve as additional indicators of ALF severity.

  11. Serum Levels of Follistatin Are Positively Associated With Serum-Free Thyroxine Levels in Patients With Hyperthyroidism or Euthyroidism

    Science.gov (United States)

    Tseng, Fen-Yu; Chen, Yen-Ting; Chi, Yu-Chao; Chen, Pei-Lung; Yang, Wei-Shiung

    2016-01-01

    Abstract Follistatin is a glycoprotein with various biologic functions that plays a role in adipocyte differentiation, muscle stimulation, anti-inflammation, and energy homeostasis. Thyroid hormones influence energy expenditure, glucose, and lipid metabolism. The association between serum follistatin level and thyroid function statuses has seldom been evaluated. The objectives of this study were to compare serum follistatin concentrations in different thyroid function statuses and to evaluate the associations between serum follistatin and free thyroxine (fT4) levels. In this study, 30 patients with hyperthyroidism (HY group) and 30 euthyroid individuals (EU group) were recruited. The patients of HY group were treated with antithyroid regimens as clinically indicated, whereas no medication was given to EU group. The demographic and anthropometric characteristics, biochemical data, serum levels of follistatin, and thyroid function of both groups at baseline and at the 6th month were compared. Data of all patients were pooled for the analysis of the associations between the levels of follistatin and fT4. At baseline, the HY group had significantly higher serum follistatin levels than the EU group (median [Q1, Q3]: 1.81 [1.33, 2.78] vs 1.13 [0.39, 1.45] ng/mL, P hyperthyroidism had higher serum follistatin levels, which decreased after receiving antithyroid treatment. In addition, the serum follistatin concentrations were positively associated with serum fT4 levels in patients with hyperthyroidism or euthyroidism. PMID:26844494

  12. Variable Suppression of Serum Thyroxine in Female Mice of Different Inbred Strains by Triiodothyronine Administered in Drinking Water

    Science.gov (United States)

    Hamidi, Sepehr; Aliesky, Holly; Chen, Chun-Rong; Rapoport, Basil

    2010-01-01

    Background Recombinant-inbred mouse strains differ in their susceptibility to Graves'-like hyperthyroidism induced by immunization with adenovirus expressing the human thyrotropin (TSH) receptor. Because one genetic component contributing to this susceptibility is altered thyroid sensitivity to TSH receptor agonist stimulation, we wished to quantify thyroid responsiveness to TSH. For such studies, it is necessary to suppress endogenous TSH by administering L-3,5,3′-triiodothyronine (L-T3), with the subsequent decrease in serum thyroxine (T4) reflecting endogenous TSH suppression. Our two objectives were to assess in different inbred strains of mice (i) the extent of serum T4 suppression after L-T3 administration and (ii) the magnitude of serum T4 increase induced by TSH. Methods Mice were tail-bled to establish baseline-serum T4 before L-T3 administration. We initially employed a protocol of L-T3-supplemented drinking water for 7 days. In subsequent experiments, we injected L-T3 intraperitoneally (i.p.) daily for 3 days. Mice were then injected i.p. with bovine TSH (10 mU) and euthanized 5 hours later. Serum T4 was assayed before L-T3 administration, and before and after TSH injection. In some experiments, serum T3 and estradiol were measured in pooled sera. Results Oral L-T3 (3 or 5 μg/mL) suppressed serum T4 levels by 26%–64% in female BALB/c mice but >95% in males. T4 suppression in female B6 mice ranged from 0% to 90%. In C3H mice, L-T3 at 3 μg/mL was ineffective but 5 μg/mL achieved >80% serum T4 reduction. Unlike inbred mice, in outbred CF1 mice the same protocol was more effective: 83% in females and 100% suppression in males. The degree of T4 suppression was unrelated to baseline T4, T3, or estradiol, but was related to mouse weight and postmortem T3, with greater suppression in larger mice (outbred CF1 animals and inbred males). Among females with serum T4 suppression >80%, the increase in serum T4 after TSH injection was greater for BALB

  13. Measurement of free thyroxine or free 3,5,3'-triiodothyronine in a liquid sample

    International Nuclear Information System (INIS)

    Hertl, W.; Ward, F.B.; Weetall, H.H.

    1982-01-01

    An immunoassay method is described for the direct measurement of free thyroxine or 3,5,3'-triiodothyronine in a liquid sample in which the thyroxine or 3,5,3'-triiodothyronine is present in both free and combined states. The sample is combined with a labelled thyroxine- or 3,5,3'-triiodothyronine-horseradish peroxidase conjugate which does not significantly interact with thyroxine-binding globulin, thyroxine-binding prealbumin and immobilised antibody which is specific for thyroxine or 3,5,3'-triiodothyronine. After incubation, the solid phase is separated from the liquid phase and the amount of labelled thyroxine- or 3,5,3'-triiodothyronine-horseradish peroxidase conjugate present in either phase is measured by determining the activity of the label. (author)

  14. Results of preoperative chemoradiotherapy for T4 rectal cancer

    International Nuclear Information System (INIS)

    Sato, Harunobu; Maeda, Koutarou; Masumori, Koji; Koide, Yoshikazu; Noro, Tomohito; Honda, Katsuyuki; Shiota, Miho; Matsuoka, Shinji; Toyama, Kunihiro

    2011-01-01

    We reviewed clinical records of 11 cases with preoperative chemoradiotherapy to evaluate the clinical effectiveness of chemoradiotherapy for T4 rectal cancer. The preoperative radiotherapy consisted of 40-50 Gy delivered in fractions of 1.8-2.0 Gy per day, five days per week. A treatment of 5-fluorouracil, 500 mg/body per day intravenously, or oral tegafur-uracil (UFT)-E (300 mg/m 2 ) with l-leucovorin (75 mg) per day, or oral S-1 (80 mg/m 2 ) per day five days per week, was given during radiotherapy. One patient died due to pelvic abscess in 63 days after chemoradiotherapy. Invasive findings to the adjacent organs identified by CT and MRI disappeared in 6 cases with complete or partial response 1 month after chemoradiotherapy. Curative surgery was performed in 7 patients. Although the adjacent organs were also removed during surgery in 7 patients, there was no histological invasion to the adjacent organs in 4 patients, and one patient had histological complete disappearance of tumor. Although complications after surgery were found in all of the patients, they were improved by conservative treatment. Two of 7 patients with curative surgery had recurrence, but the rest of them survived without recurrence. Preoperative chemoradiotherapy was expected to be an effective treatment to improve the resection rate and prognosis for T4 rectal cancer. However, it was thought that it was necessary to be careful about severe toxicity, such as pelvic abscess. (author)

  15. Treatment Outcomes for T4 Oropharyngeal Squamous Cell Carcinoma.

    Science.gov (United States)

    Zenga, Joseph; Wilson, Michael; Adkins, Douglas R; Gay, Hiram A; Haughey, Bruce H; Kallogjeri, Dorina; Michel, Loren S; Paniello, Randal C; Rich, Jason T; Thorstad, Wade L; Nussenbaum, Brian

    2015-12-01

    Little is known about treatment outcomes for T4 oropharyngeal squamous cell carcinoma (OPSCC), particularly in the era of human papillomavirus (HPV)-related disease. To evaluate oncologic outcomes for T4 OPSCC treated with primary surgical and nonsurgical therapies. Retrospective cohort study of 131 patients from a single academic hospital, who were treated for T4a or T4b OPSCC (with any N stage and without distant metastatic disease at presentation) between 1998 and 2012 and had a minimum 2-year follow-up (the median follow-up time was 34.6 months). This study was conducted between January 1, 1998, and November 1, 2012. Sixty-nine patients underwent nonsurgical therapy, 47 (68%) of whom had p16-positive tumors. Nonsurgical treatment paradigms included induction chemotherapy followed by chemoradiotherapy (n = 36 [54%]), concurrent chemoradiotherapy (n = 29 [43%]), and induction chemotherapy followed by radiation therapy alone (n = 2 [3%]). Sixty-two patients underwent surgical treatment, 50 (81%) of whom had p16-positive tumors. Fifty-seven surgical patients (92%) received adjuvant therapy. Overall survival (OS) was the primary outcome measure. Secondary outcome measures included disease-specific survival (DSS), disease-free survival (DFS), 2-year gastrostomy and tracheostomy tube rates, and major complication rates. Significant baseline differences between the surgical vs nonsurgical groups included age (mean 59.8 vs 55.4 years [P = .005]), sex (male, 95% vs 84% [P = .04]), body mass index (<18.5 [calculated as weight in kilograms divided by height in meters squared], 3% vs 16% [P = .02]), and smoking history of 10 or more pack-years (48% vs 77% [P = .003]). For p16-positive patients, Kaplan-Meier estimates of OS, DSS, and DFS were significantly higher for surgically treated patients than for the nonsurgical group (χ(2)(1) = 7.335 for log-rank P = .007, χ(2)(1) = 8.607 for log-rank P = .003, and χ(2)(1) = 7.763 for log-rank P = .005, respectively

  16. Serum levels of T3 and T4 among workers of contraceptive pills industry

    International Nuclear Information System (INIS)

    Abbas, E.Z.; Emara, A.; Yassen, Y.Z.; Amr, M.M.; Jaras, M.S.

    1985-01-01

    Serum levels of thyroxine and triiodothyronine were determined in 24 workers engaged in contraceptive pills industry and 20 control subjects. Serum thyroxine in exposed subjects was significantly lower, compared to its level in controls. On the other hand, triiodothyronine was significantly higher in exposed workers. Thus, it is concluded that exposure to the dust of contraceptive drugs, namely estrogen and progesterone, produced disturbances in thyroid gland function and thyroid hormone metabolism. (author)

  17. Study on the thyroid function of thoroughbred horses by means of 'in vitro' 125I-T3 modified and 125I-T4 tests

    International Nuclear Information System (INIS)

    Martin, B.W. de

    1975-01-01

    Sera of 71 animals, divided in groups of males and females, in repose and after activity were studied. The method to establish the percentage of the 125 I-lyothyronine retention in resin (Test 125 I-T 3 or T 3 ) was modified by the use of 0.2 ml of serum on the resin column, after addition of the marked hormone. This modification served to prove that thoroughbred equines show binding of the I-lyothyronine to the serum four times reduced, indicating, therefore, that these animals have four times more ligation sites of triidothyronin saturation in the serum, when compared with the results obtained from human beings. The variance analysis applied to the T 3 Test showed no significant results at the 95% level as regards to activity. For the 71 animals, the author has found an average of 50.30% of the 125 I-Lyothyronine in resin retention, being the confidence interval for this group between 48.75% and 51.85% to a 95% confidence coefficient. Evaluating the results of the T 4 Test by means of the variance analysis, we noticed that the male and female groups in repose differed statistically from the groups after activity to a 95% confidence coefficient. The author has grouped the results of the T 4 Test of 32 equines, 18 males and 14 females, in repose, obtaining an average of 0.61 mcg and 0.51 mcg and 0.71 mcg T 4 /100 ml as confidence interval to a 95% confidence coefficient. We have listed 39 results of T 4 Test, being 23 males and 61 Females, after activity, obtaining an average of 2.01 mcg of thyroxin by 100 ml of serum and 1.72 mcg and 2.30 T 4 /100 ml as confidence interval to a 95% confidence coefficient

  18. Direct determination of free thyroxine in two simultaneous radioimmunoassays with different test principles

    International Nuclear Information System (INIS)

    Lohkamp, F.; Schmidt, M.

    1982-01-01

    Serum FT 4 was measured simultaneously by the commercial FT 4 kits of Amersham-Buchler and Corning Medical in 4 groups with defined thyroid function as follows: 57 euthroid subjects with and without goitre, 27 patients on T 4 supplementation. 12 subjects on oral contraceptives and 26 subclinically hyperthyroid patients. All patients underwent physical examination, thyroid scintigraphy and additional in-vitro tests (total thyroxine T 4 , total triiodothyronine T 3 and TRH/TSH assay). Both assays generally correlated well with the definded thyroid functional status except for the patients on oral contraceptives. Contrary to the FT 4 -test (Amersham-Buchler) in this group the FT 4 -test (Corning Medical) produced a significantly increased mean for FT 4 as compared to the euthyroid group thus indicating a probably insufficient compensation for high but not necessarily abnormal levels of TBG concentration. Using the FT 4 -assay (Amersham-Buchler) the normal range of FT 4 values of euthyroid subjects from the area of Bamberg with marked iodine deficiency agrees well with recently published results of a multicentre trial thus confirming the assumption of serum FT 4 not being strongly dependent on iodine intake. The results of the FT 4 -test (Corning) showed a wider scatter of normal ranges of FT 4 values for all groups and concomitantly reduced discrimination compared to the corresponding simultaneously obtained FT 4 -test (Amersham-Buchler) results. Though cost and time saving, the commercial radioimmunoassays will require further critical evaluation of normal range validity on larger populations of defined abnormalities will require further critical evaluation of normal range validity on larger populations of defined abnormalities of thyroid function to elucidate inherent deficiencies of the new FT 4 methods and of their diagnostic efficiency. (orig./MG) [de

  19. Quantum thetas on noncommutative T4 from embeddings into lattice

    International Nuclear Information System (INIS)

    Chang-Young, Ee; Kim, Hoil

    2007-01-01

    In this paper, we investigate the theta vector and quantum theta function over noncommutative T 4 from the embedding of RxZ 2 . Manin has constructed the quantum theta functions from the lattice embedding into vector space (x finite group). We extend Manin's construction of the quantum theta function to the embedding of vector space x lattice case. We find that the holomorphic theta vector exists only over the vector space part of the embedding, and over the lattice part we can only impose the condition for the Schwartz function. The quantum theta function built on this partial theta vector satisfies the requirement of the quantum theta function. However, two subsequent quantum translations from the embedding into the lattice part are nonadditive, contrary to the additivity of those from the vector space part

  20. Influence of carbamazepin and diclofenac on the radio-T3/T4-distribution and the maximal binding capacity of thyroid hormone binding proteins

    International Nuclear Information System (INIS)

    Sternad, H.; Albrecher, B.; Langsteger, W.; Eber, O.

    1993-01-01

    Marked changes in plasma thyroid function parameters due to medication have been described in literature. We, therefore, studied the influence of routine administration of carbamazepine and diclofenac upon the radio T3/T4 distribution to specific thyroid transport proteins as well as their maximal binding capacity (MBC) for T4. Both drugs have been found to lead to changes in T3 and T4 distribution but not to any influence upon MBC. The parameters of thyroid function mostly revealed reduced FT3 and FT4 values while bTSH was affected only by carbamazepine administration. (authors)

  1. An improved 96-well turbidity assay for T4 lysozyme activity.

    Science.gov (United States)

    Toro, Tasha B; Nguyen, Thao P; Watt, Terry J

    2015-01-01

    T4 lysozyme (T4L) is an important model system for investigating the relationship between protein structure and function. Despite being extensively studied, a reliable, quantitative activity assay for T4L has not been developed. Here, we present an improved T4L turbidity assay as well as an affinity-based T4L expression and purification protocol. This assay is designed for 96-well format and utilizes conditions amenable for both T4L and other lysozymes. This protocol enables easy, efficient, and quantitative characterization of T4L variants and allows comparison between different lysozymes. Our method: •Is applicable for all lysozymes, with enhanced sensitivity for T4 lysozyme compared to other 96-well plate turbidity assays;•Utilizes standardized conditions for comparing T4 lysozyme variants and other lysozymes; and•Incorporates a simplified expression and purification protocol for T4 lysozyme.

  2. A method of radiocompetitive assay of total thyroxine in the serum by means of enzymatic release of thyroxine from the transporting proteins

    International Nuclear Information System (INIS)

    Snarski, A.; Wyrwinski, J.

    1978-01-01

    Pepsin causes denaturation of the transporting proteins and liberates thyroxine which can be assayed by the radiocompetitive method. Change of the pH of the medium from acid to alkaline inactivates irreveribly pepsin. The enzymatic release of thyroxine is much simpler that the method of ethanol extraction and thermal denaturation of the transporting proteins applied up to now. The new technique of thyroxine release has been introduced for radiocompetitive determination of thyroxine using dextran coated charcoal for adsorption of the free hormone. A new method has been elaborated for preparation of working standards of thyroxine in a mixture of pepsin solution with hormone-free serum. The method is efficient and rapid. The normal range is from 50 to 130 nanomol/l. Over 7 000 determinations were done as yet in patients with suspected thyroid function disturbances. (author)

  3. Effect of thyroxine on brain microstructure in extremely premature babies: magnetic resonance imaging findings in the TIPIT study.

    Science.gov (United States)

    Ng, Sze May; Turner, Mark A; Gamble, Carrol; Didi, Mohammed; Victor, Suresh; Atkinson, Jessica; Sluming, Vanessa; Parkes, Laura M; Tietze, Anna; Abernethy, Laurence J; Weindling, Alan Michael

    2014-08-01

    In order to assess relationships between thyroid hormone status and findings on brain MRI, a subset of babies was recruited to a multi-centre randomised, placebo-controlled trial of levothyroxine (LT4) supplementation for babies born before 28 weeks' gestation (known as the TIPIT study, for Thyroxine supplementation In Preterm InfanTs). These infants were imaged at term-equivalence. Forty-five TIPIT participants had brain MRI using diffusion tensor imaging (DTI) to estimate white matter development by apparent diffusion coefficient (ADC), fractional anisotropy (FA) and tractography metrics of number and length of streamlines. We made comparisons between babies with the lowest and highest plasma FT4 concentrations during the initial 4 weeks after birth. There were no differences in DTI metrics between babies who had received LT4 supplementation and those who had received a placebo. Among recipients of a placebo, babies in the lowest quartile of plasma-free thyroxine (FT4) concentrations had significantly higher apparent diffusion coefficient measurements in the posterior corpus callosum and streamlines that were shorter and less numerous in the right internal capsule. Among LT4-supplemented babies, those who had plasma FT4 concentrations in the highest quartile had significantly lower apparent diffusion coefficient values in the left occipital lobe, higher fractional anisotropy in the anterior corpus callosum and longer and more numerous streamlines in the anterior corpus callosum. DTI variables were not associated with allocation of placebo or thyroid supplementation. Markers of poorly organised brain microstructure were associated with low plasma FT4 concentrations after birth. The findings suggest that plasma FT4 concentrations affect brain development in very immature infants and that the effect of LT4 supplementation for immature babies with low FT4 plasma concentrations warrants further study.

  4. Effects of thyroxine and 1-methyl, 2-mercaptoimidazol on phosphoinositides synthesis in rat liver

    Directory of Open Access Journals (Sweden)

    Krasilnikova Oksana A

    2004-12-01

    Full Text Available Abstract Background Phosphoinositides mediate one of the intracellular signal transduction pathways and produce a class of second messengers that are involved in the action of hormones and neurotransmitters on target cells. Thyroid hormones are well known regulators of lipid metabolism and modulators of signal transduction in cells. However, little is known about phosphoinositides cycle regulation by thyroid hormones. The present paper deals with phosphoinositides synthesis de novo and acylation in liver at different thyroid status of rats. Results The experiments were performed in either the rat liver or hepatocytes of 90- and 720-day-old rats. Myo-[3H]inositol, [14C]CH3COONa, [14C]oleic and [3H]arachidonic acids were used to investigate the phosphatidylinositol (PtdIns, phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate (PtdInsP2 synthesis. 1-methyl, 2-mercaptoimidazol-induced hypothyroidism was associated with the decrease of myo-[3H]inositol and [3H]arachidonic acids incorporation into liver phosphoinositides and total phospholipids, respectively. The thyroxine (L-T4 injection to hypothyroid animals increased the hormones contents in blood serum and PtdInsP2 synthesis de novo as well as [3H]arachidonic acids incorporation into the PtdIns and PtdInsP2. Under the hormone action, the [14C]oleic acid incorporation into PtdIns reduced in the liver of hypothyroid animals. A single injection of L-T4 to the euthyroid [14C]CH3COONa-pre-treated animals or addition of the hormone to a culture medium of hepatocytes was accompanied by the rapid prominent increase in the levels of the newly synthesized PtdIns and PtdInsP2 and in the mass of phosphatidic acid in the liver or the cells. Conclusions The data obtained have demonstrated that thyroid hormones are of vital importance in the regulation of arachidonate-containing phosphoinositides metabolism in the liver. The drug-induced malfunction of thyroid gland noticeably changed the

  5. Exposure of Pregnant Mice to Triclosan Causes Insulin Resistance via Thyroxine Reduction.

    Science.gov (United States)

    Hua, Xu; Cao, Xin-Yuan; Wang, Xiao-Li; Sun, Peng; Chen, Ling

    2017-11-01

    Exposure to triclosan (TCS), an antibacterial agent, during pregnancy is associated with hypothyroxinemia and decreases in placental glucose transporter expression and activity. The objective of this study was to investigate the influence of TCS on glucose homeostasis and insulin sensitivity in gestational mice (G-mice) and nongestational female mice (Ng-mice) as a control. Herein, we show that the exposure of G-mice to TCS (8 mg/kg) from gestational day (GD) 5 to GD17 significantly increased their levels of fasting plasma glucose and serum insulin, and insulin content in pancreatic β-cells with reduced homeostasis model assessment (HOMA)-β index and increased HOMA-IR index. Area under curve (AUC) of glucose and insulin tolerance tests in TCS (8 mg/kg)-treated G-mice were markedly larger than controls. When compared with controls, TCS (8 mg/kg)-treated G-mice showed a significant decrease in the levels of thyroxine and triiodothyroninelevels, PPARγ and glucose transporter 4 (GLUT4) expression, and Akt phosphorylation in adipose tissue and muscle. Replacement of L-thyroxine in TCS (8 mg/kg)-treated G-mice corrected their insulin resistance and recovered the levels of insulin, PPARγ and GLUT4 expression, and Akt phosphorylation. Activation of PPARγ by administration of rosiglitazone recovered the decrease in Akt phosphorylation, but not GLUT4 expression. Although exposure to TCS (8 mg/kg) in Ng-mice reduced thyroid hormones levels, it did not cause the insulin resistance or affect PPARγ and GLUT4 expression, and Akt phosphorylation. The findings indicate that the exposure of gestational mice to TCS (≥8 mg/kg) results in insulin resistance via thyroid hormones reduction. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Assessment of a method for measuring serum thyroxine by radioimmunoassay, with use of polyethylene glycol precipitation

    International Nuclear Information System (INIS)

    Farid, N.R.; Kennedy, C.

    1977-01-01

    We assessed the efficacy of a new thyroxine radioimmunoassay kit (Abbott) in which polyethylene glycol is used to separate bound from free hormone. Mean serum thyroxine was 88 +- 15 (+-SD) μg/liter for 96 normal persons. Results for hypothyroid and hyperthyroid persons were clearly separated from those for normal individuals. Women taking oral contraceptive preparations showed variable increases in their serum thyroxine values. The coefficient of variation ranged from 1 to 3% within assay and from 5.4 to 11% among different assays. Excellent parallelism was demonstrated between thyroxine values estimated by this method and those obtained either by competitive protein binding or by a separate radioimmunoassay for the hormone

  7. Comparative evaluation of therapy with L-thyroxine versus no treatment in children with idiopathic and mild subclinical hypothyroidism.

    Science.gov (United States)

    Wasniewska, Malgorzata; Corrias, Andrea; Aversa, Tommaso; Valenzise, Mariella; Mussa, Alessandro; De Martino, Lucia; Lombardo, Fortunato; De Luca, Filippo; Salerno, Mariacarolina

    2012-01-01

    The question of whether children with subclinical hypothyroidism (SH) should be treated or not is controversial due to the lack of studies on outcomes of SH children treated with L-thyroxine (L-T(4)) versus those receiving no therapy. (a) To evaluate thyroid tests under L-T(4) and after therapy withdrawal in 69 SH children (group A) and (b) to compare our results with those recorded in 92 untreated children (group B). Group A children were treated for 24 months and TSH and FT(4) levels 3 months after therapy withdrawal were compared with those measured in group B at the end of follow-up in order to investigate treatment effects. The prevalence of children who had normalized TSH at the end of follow-up was higher in group A, but the prevalence of those who had normalized or maintained unchanged TSH was similar in the two groups, as was the prevalence of children who exhibited a TSH increase >10 mU/l. In group A, TSH values at 27 months were associated with baseline values. (a) Two-year treatment in SH children is unable to modify posttherapy outcome of hyperthyrotropinemia; (b) therapy is unable to prevent the risk of further TSH increase after treatment withdrawal, and (c) posttherapy TSH outcome is conditioned by baseline TSH. Copyright © 2012 S. Karger AG, Basel.

  8. Alteration of Hemostatic Parameters in Patients with Different Levels of Subclinical Hypothyroidism and the Effect of L-thyroxine Treatment.

    Science.gov (United States)

    Gao, Fang; Wang, Guangya; Xu, Jinxiu

    2017-01-01

    Subclinical hypothyroidism (SH) is associated with hypercoagulability and hypofibrinolysis. The objective of this study was to assess the effect of L-thyroxine (L-T4) treatment and to evaluate changes in the hemostatic abnormalities of patients with varying severities of SH. We measured tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), D-dimer (DDI), fibrinogen (FIB), platelet counts (PLT), mean platelet volume (MPV), platelet distribution width (PDW), activated partial thromboplastin time (APTT), and prothrombin time (PT) in 149 female subjects. The prospective study included 54 patients in the control group, 53 patients with 4.2 μIU/mLtreatment, a significant decrease in FIB, PAI-1 and t-PA levels and an increase in APTT and DDI were observed in the severe SH group. In conclusion, SH patients displayed a distinct pattern of alteration of hemostatic parameters that was dependent on the severity of the disease. Patients with TSH levels ≥10 μIU/mL displayed hypercoagulability, which was reversed by 6 months of L-T4 treatment. © 2017 by the Association of Clinical Scientists, Inc.

  9. Severe Hypothyroidism due to the Loss of Therapeutic Efficacy of l-Thyroxine in a Patient with Esophageal Complication Associated with Systemic Sclerosis.

    Science.gov (United States)

    Lobasso, Antonio; Nappi, Liliana; Barbieri, Letizia; Peirce, Carmela; Ippolito, Serena; Arpaia, Debora; Rossi, Francesca Wanda; de Paulis, Amato; Biondi, Bernadette

    2017-01-01

    Thyroid function abnormalities and thyroid autoantibodies have been frequently described in patients with systemic autoimmune diseases as systemic sclerosis (SSc). Serum TSH levels are higher in SSc patients with more severe skin diseases and a worse modified Rodnan skin score. Asymptomatic esophageal involvement due to SSc has never been described as a cause of severe hypothyroidism due to l-thyroxine (l-T4) malabsorption in patients with Hashimoto's thyroiditis (HT) and SSc. Here, we report a case of a 56-year-old female affected by both SSc and HT who developed severe hypothyroidism due to the loss of therapeutic efficacy of l-T4. Therapeutic failure resulted from the altered l-T4 absorption because of SSc esophageal complications. Clinical findings improved after the administration of oral liquid l-T4. Thyroid function completely normalized with a full clinical recovery, the disappearance of the pericardial effusion and the improvement of the pulmonary pressure. A recognition of a poor absorption is crucial in patients with hypothyroidism and SSc to reduce the risk of the subsequent adverse events. This case suggests the importance of clinical and laboratory surveillance in patients with SSc and HT because the systemic complications of these dysfunctions may worsen the prognosis of hypothyroid SSc/HT patients.

  10. Severe Hypothyroidism due to the Loss of Therapeutic Efficacy of l-Thyroxine in a Patient with Esophageal Complication Associated with Systemic Sclerosis

    Directory of Open Access Journals (Sweden)

    Antonio Lobasso

    2017-09-01

    Full Text Available BackgroundThyroid function abnormalities and thyroid autoantibodies have been frequently described in patients with systemic autoimmune diseases as systemic sclerosis (SSc. Serum TSH levels are higher in SSc patients with more severe skin diseases and a worse modified Rodnan skin score. Asymptomatic esophageal involvement due to SSc has never been described as a cause of severe hypothyroidism due to l-thyroxine (l-T4 malabsorption in patients with Hashimoto’s thyroiditis (HT and SSc.Case reportHere, we report a case of a 56-year-old female affected by both SSc and HT who developed severe hypothyroidism due to the loss of therapeutic efficacy of l-T4. Therapeutic failure resulted from the altered l-T4 absorption because of SSc esophageal complications. Clinical findings improved after the administration of oral liquid l-T4. Thyroid function completely normalized with a full clinical recovery, the disappearance of the pericardial effusion and the improvement of the pulmonary pressure.ConclusionA recognition of a poor absorption is crucial in patients with hypothyroidism and SSc to reduce the risk of the subsequent adverse events. This case suggests the importance of clinical and laboratory surveillance in patients with SSc and HT because the systemic complications of these dysfunctions may worsen the prognosis of hypothyroid SSc/HT patients.

  11. HUBUNGAN KADAR TIROGLOBULIN, TSH DAN fT4 SERUM PADA ANAK USIA SEKOLAH DI TIGA KABUPATEN DENGAN TINGKAT ENDEMISITAS DEFISIENSI-IODIUM BERBEDA (ASSOCIATION BETWEEN THE SERUM THYROGLOBULIN, TSH, AND fT4 AMONG SCHOOL-AGED CHILDREN IN THREE DISTRICTS WITH DIF

    Directory of Open Access Journals (Sweden)

    Agus Wibowo

    2013-06-01

    Full Text Available ABSTRACT Iodine deficiency lowers circulating thyroxine (T4 and raises serum Thyroid Stimulating Hormone (TSH, where free T4 (fT4 and TSH have strong corelation with thyroglobulin (Tg. The results from population studies indicate, Tg appears to be a valuable indicator of thyroid status, but it has yet to be fully explored. This study aimed to measure the association between serum Tg with TSH and fT4 as alternatif indicators thyroid status in school-aged children. This was a cross-sectional study of sample of 398 schoolchildren aged 10-12 years in three districts with different iodine-deficiency endemicity level, i.e. Pati as a mild endemic district, Purbalingga as a moderate endemic district, and Malang as a severe endemic district. Children’s blood have taken 3 cc as a sample for the determination of Tg, TSH, and fT4. Enzyme-Linked Immunosorbent Assay (ELISA was used to determine Tg, TSH and fT4. Mean of serum Tg 14.3 ± 11.1 ng/mL (cut-off 2-50 ng/mL, TSH 3.7 ± 2.2 µIU/mL (cut-off 0.3-6.2, fT4 1.4 ± 0.4 ng/dL (cut-off 0.8-2.0 ng/dL. Correlation analysis was showed the significance of Tg and TSH (p< 0.05 and Tg with fT4 (p< 0.05. The significance analysis of Tg with TSH and fT4 may be evaluated as indicator  for thyroid function in school-aged children in iodine-deficiency endemic areas.   Keywords: thyroglobulin (Tg, Thyroid Stimulating Hormone (TSH, free thyroxine (fT4, school-aged children ABSTRAK Defisiensi iodium menurunkan tiroksin (T4 yang beredar dalam darah dan meningkatkan Thyroid Stimulating Hormone (TSH, di mana T4 bebas (fT4 dan TSH memiliki hubungan erat dengan tiroglobulin (Tg. Hasil studi populasi menunjukkan, Tg tampak menjadi indikator berharga untuk status tiroid di daerah endemik defisiensi iodium, tetapi belum sepenuhnya dieksplorasi. Penelitian ini bertujuan mengukur hubungan antara kadar Tg serum dengan kadar TSH dan fT4 sebagai indikator alternatif status tiroid pada anak usia sekolah. Ini merupakan penelitian

  12. Acute redistribution of thyroxine after the administration of univalent anions, salicylate, theophylline and barbiturates in rats

    Energy Technology Data Exchange (ETDEWEB)

    Langer, P; Kokesova, H; Gschwendtova, K [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Ustav Experimentalni Endocrinologie

    1976-01-01

    Rats were injected with (/sup 125/I)L-thyroxine (T/sub 4/) ip 16 h before the experiment and samples of blood were frequently taken from polyethylene tubing inserted into the femoral artery in anaesthetized and heparin-injected animals. In each sample of plasma T/sub 4/ counts per ml were estimated with the acid of paper chromatography. Rapid decrease of circulating T/sub 4/ level was found at 20 min after iv injection of thiocyanate, iodide, fluoroborate, theophylline and salicylate and a dose-response relationship was established between such a decrease and the administered dose of salicylate (5-160 mg/400 g b.w.). A similar decrease was observed at 60 min after ip injection of some general anaesthetics or tranquilizers. An increase of T/sub 4/ fractional disposal rate was found between 120 and 480 min after the administration of some of the anaesthetics and this effect was abolished by the administration of thiocyanate. It was concluded that there are two different effects of drugs on the circulating T/sub 4/ level: 1. the immediate effect resulting apparently from a decreased plasma protein binding. 2. the prolonged effect which presumably results from the increased turnover of T/sub 4/ by peripheral tissues, the metabolic basis of which remains unexplained.

  13. Influence of adsorption and deproteination on potential free thyroxine reference methods

    DEFF Research Database (Denmark)

    Holm, Steen S; Andreasen, Lisbeth; Hansen, Palle Steen

    2002-01-01

    There is a need for consensus concerning reference methods to be used for calibration of commercial free-thyroxine (FT(4)) assays.......There is a need for consensus concerning reference methods to be used for calibration of commercial free-thyroxine (FT(4)) assays....

  14. Isoforms of thyroxine-binding globulin as a model for molecular epidemiology of human cancer risk

    International Nuclear Information System (INIS)

    Golovaty, A.S.; Lapko, A.G.

    2000-01-01

    The novel field of molecular epidemiology of human cancer risk has added a new branch to classical epidemiology by providing a direct link between human cancer and carcinogen exposure. It was estimated that about 80% of cancers are due to environmental factors. The blood proteins are almost certainly targets for modification in human cancer, and their identification and characterization will be of primary importance in the development of the new and rapidly evolving field of molecular epidemiology. Among blood proteins that are altered in human cancer, TBG occupies a special place because the level of human blood TBG is the most sensitive to intensification of biosynthesis and proliferation processes in organisms in different types of cancer. The increase of TBG concentration in cancer can be result from both activation of TBG biosynthesis in liver or altering of post translation glycosylation that prolongs protein survival time. The molecular basis for the change in the properties of TBG in cancer is unknown. These distinctive changes could have important consequences for the function of TBG in cancer and may help to develop more precise markers for monitoring pathological progression in this disease. Considerable variability and subtlety can occur in the carbohydrate composition and structure of serum glycoproteins in disease. This can be either as a major change, such as an increase in the number of oligosaccharide branches at a particular glycosylation site or as a minor change such as the addition of an extra fucose or sialic acid residue. Increased fucosylation has also been reported for transferrin and alpha-fetoprotein in liver cancer; thyroglobulin in thyroid cancer, IgG in myeloma, haptoglobin in ovarian cancer. The last own studies have shown that in clinically healthy teenagers born in Khojniki (137 Cs 185-555 kBq/m), we have found an unusual thyroid profile exhibiting increased levels of total triiodothyronine (T3), total thyroxine (T4), and thyroxine

  15. Differentiating Graves' disease from subacute thyroiditis using ratio of serum free triiodothyronine to free thyroxine.

    Science.gov (United States)

    Sriphrapradang, Chutintorn; Bhasipol, Adikan

    2016-09-01

    The measurement of free thyroid hormone, instead of the total form, is more commonly used in current practice. We aimed to evaluate the usefulness of the ratio of serum free triiodothyronine (FT3, pg/mL) to free thyroxine (FT4, ng/dL) for differentiating Graves' disease from subacute thyroiditis. Medical records of thyrotoxic patients aged >15 years who had measurement of FT3, FT4 and thyrotropin on the first diagnosis of thyrotoxicosis before initiating treatment were retrospectively reviewed. Data were collected from all clinics, and were not limited to the endocrine clinic. Pregnant women were excluded. A total of 548 patients (468 with Graves' disease, 40 with subacute thyroiditis and 40 with toxic adenoma/multinodular goiter) were recruited. Mean age was 43.9 ± 15.4 years. Most were female 434 (79.2%), and goiter was present in 55.3%. Prevalence of T3-toxicosis and T4-toxicosis were 5.6% and 6.6%, respectively. Mean FT3/FT4 ratios were 4.62 ± 2 (10(-2) pg/ng) in patients with Graves' disease and 2.73 ± 0.5 in subacute thyroiditis. The area under the ROC curve of the FT3/FT4 ratio for diagnosis of Graves' disease was 0.83 (95%CI, 0.76-0.91). Cutoff level of this ratio >4.4 offered sensitivity of 47.2% and specificity of 92.8%. FT3/FT4 ratio of >4.4 (10(-2) pg/ng) may help in differentiating the cause of thyrotoxicosis.

  16. Selective affinity labeling of a 27-kDa integral membrane protein in rat liver and kidney with N-bromoacetyl derivatives of L-thyroxine and 3,5,3'-triiodo-L-thyronine

    International Nuclear Information System (INIS)

    Koehrle, J.R.; Rasmussen, U.B.; Rokos, H.; Leonard, J.L.; Hesch, R.D.

    1990-01-01

    125I-Labeled N-bromoacetyl derivatives of L-thyroxine and L-triiodothyronine were used as alkylating affinity labels to identify rat liver and kidney microsomal membrane proteins which specifically bind thyroid hormones. Affinity label incorporation was analyzed by ethanol precipitation and individual affinity labeled proteins were identified by autoradiography after separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Six to eight membrane proteins ranging in size from 17 to 84 kDa were affinity labeled by both bromoacetyl-L-thyroxine (BrAcT4) and bromoacetyl-L-triiodothyronine (BrAcT3). Affinity labeling was time- and temperature-dependent, and both reduced dithiols and detergents increased affinity labeling, predominantly in a 27-kDa protein(s). Up to 80% of the affinity label was associated with a 27-kDa protein (p27) under optimal conditions. Affinity labeling of p27 by 0.4 nM BrAc[125I]L-T4 was blocked by 0.1 microM of the alkylating ligands BrAcT4, BrAcT3, or 100 microM iodoacetate, by 10 microM concentrations of the non-alkylating, reversible ligands N-acetyl-L-thyroxine, 3,3',5'-triiodothyronine, 3,5-diiodosalicylate, and EMD 21388, a T4-antagonistic flavonoid. Neither 10 microM L-T4, nor 10 microM N-acetyltriiodothyronine or 10 microM L-triiodothyronine blocked affinity labeling of p27 or other affinity labeled bands. Affinity labeling of a 17-kDa band was partially inhibited by excess of the alkylating ligands BrAcT4, BrAcT3, and iodoacetate, but labeling of other minor bands was not blocked by excess of the competitors. BrAc[125I]T4 yielded higher affinity label incorporation than BrAc[125I]T3, although similar banding patterns were observed, except that BrAcT3 affinity labeled more intensely a 58,000-Da band in liver and a 53,000-55,000-Da band in kidney

  17. Method for the radioimmunological in-vitro determination of thyroxine and packed test kit to carry out this method

    International Nuclear Information System (INIS)

    Salvatore, M.S.

    1977-01-01

    According to the invention a radioimmunoassay has been developed for the in-vitro determination of thyroxine in non-extracted blood serum. The radioactive thyroxine is labelled with iodine 125 or iodine 131. The corresponding antiserum contains special thyroxine antibodies. The immunogen to produce the antiserum contains a conjugate of the N-acetyl derivative of thyroxine compled to bovin serum albumin with 1-ethyl-3-(3-dimethyl-amino-propyl)-carbodiimide. (VJ) [de

  18. Plasma concentrations of free triiodothyronine predict weight change in euthyroid persons2

    Science.gov (United States)

    Ortega, Emilio; Pannacciulli, Nicola; Bogardus, Clifton; Krakoff, Jonathan

    2007-01-01

    Background Factors that influence energy metabolism and substrate oxidation, such as thyroid hormones (THs), may be important regulators of body weight. Objective We investigated associations of THs cross-sectionally with obesity, energy expenditure, and substrate oxidation and prospectively with weight change. Design Euthyroid, nondiabetic, healthy, adult Pima Indians (n = 89; 47 M, 42 F) were studied. Percentage body fat (%BF) was measured by using dual-energy X-ray absorptiometry; sleeping metabolic rate (SMR), respiratory quotient, and substrate oxidation rates were measured in a respiratory chamber. Thyroid-stimulating hormone (TSH), free thyroxine (T4), free triiodothyronine (T3), and leptin concentrations were measured in fasting plasma samples. Results TSH, but neither free T3 nor free T4, was associated with %BF and leptin concentrations (r = 0.27 and 0.29, respectively; both: P ≤ 0.01). In multiple regression analyses adjusted for age, sex, fat mass, and fat-free mass, free T3 was a positive predictor of SMR (P = 0.02). After adjustment for age, sex, %BF, and energy balance, free T3 was a negative predictor of 24-h respiratory quotient (P < 0.05) and a positive predictor of 24-h lipid oxidation rate (P = 0.006). Prospectively, after an average follow-up of 4 ± 2 y, the mean increase in weight was 3 ± 9 kg. Baseline T3 concentrations were associated with absolute and annual percentage of changes in weight (r = −0.27, P = 0.02, and r = −0.28, P = 0.009, for the age-and sex-adjusted associations, respectively). Conclusions In euthyroid Pima Indians, lower free T3 but not free T4 concentrations were an independent predictor of SMR and lipid oxidation and a predictor of weight gain. This finding indicates that control of T4-to-T3 conversion may play a role in body weight regulation. PMID:17284741

  19. Pituitary hyperplasia: a complication of the pseudomalabsorption of thyroxine

    Directory of Open Access Journals (Sweden)

    Doyle MA

    2013-04-01

    Full Text Available Mary-Anne Doyle, Heather A Lochnan Division of Endocrinology, University of Ottawa, Ottawa, ON, Canada Objective: “The pseudomalabsorption of thyroxine” has been used to describe patients with hypothyroidism who fail to comply with their treatment. We describe a unique case of a 32-year-old with hypothyroidism who developed pituitary hyperplasia and hyperprolactinemia secondary to the pseudomalabsorption of thyroxine. Investigations and treatment: After baseline thyroid-function tests were performed, the patient was administered levothyroxine 0.5 mg under the supervision of a registered nurse. Thyroid function testing was repeated at 30, 60, 120, and 180 minutes. Arrangements were made for further daily supervised loading of levothyroxine 0.1 mg. Results: With the administration of 0.5 mg levothyroxine, free thyroxine levels increased by 120 minutes, and with daily supervised dosing of 0.1 mg there was normalization of the thyroid hormone levels and a reduction of thyroid-stimulating hormone levels. Maintenance of thyroid-stimulating hormone < 15 mU/L for 2 weeks led to a reduction in prolactin levels and regression in the size of the pituitary on magnetic resonance imaging. Conclusion: If left untreated, these patients face significant morbidity and are at risk of developing pituitary hyperplasia, complications from an increase in pituitary size, hyperprolactinemia, and potentially myxedema coma. Recognizing pituitary hyperplasia and hyperprolactinemia as a complication from the pseudomalabsorption of levothyroxine may prevent the potential of a misdiagnosis of a prolactinoma leading to unnecessary investigations and inappropriate treatment. Patient awareness of this serious complication and the rapid, demonstrable resolution with adequate thyroid hormone replacement may provide motivation to comply with supervised dosing of levothyroxine. It has also been suggested that supervised treatment enables the individual to maintain their patient

  20. Global skeletal uptake of technetium-99m methylene diphosphonate in female patients receiving suppressive doses of L-thyroxine for differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Frusciante, V.; Dicembrino, F.; Carnevale, V.; Scillitani, A.; Zingrillo, M.; Ghiggi, M.R.; Giannatempo, G.M.; Minisola, S.

    1998-01-01

    This study was carried out in order to investigate the possible detrimental effects on bone of levothyroxine (l-T 4 ) suppressive therapy in female patients who had undergone surgery for differentiated thyroid cancer (DTC). Twenty female (14 premenopausal and 6 postmenopausal) patients receiving l-T 4 suppressive therapy for DTC were studied. The sample was selected in such a way as to avoid factors influencing bone metabolism other than l-T 4 . All patients were monitored by sensitive thyroid-stimulating hormone, free triiodothyronine and free thyroxine assays throughout the follow-up. Nineteen healthy (12 premenopausal and 7 postmenopausal) matched women served as controls. In all subjects bone turnover was evaluated by the measurement of global skeletal uptake of technetium-99m methylene diphosphonate (GSU); bone mineral density (BMD) was measured by quantitative computed tomography at the lumbar spine (LS) and by dual-energy X-ray absorptiometry both at the LS and at three femoral sites: the femoral neck, Ward's triangle and the greater trochanter. No significant difference was found in either GSU or BMD between patients (treated for an average period of 68 months) and controls in the whole sample or in any subgroup. Furthermore, no correlations were found between either GSU or BMD and the duration of therapy, daily doses of l-T 4 or results of thyroid function tests. Our data show that carefully monitored l-T 4 therapy does not influence skeletal turnover (directly reflected by GSU) or the bone density of the spine and femur. (orig.)

  1. Distribution of /sup 125/I-thyroxine in different organs and tissues of dietically obese rats

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, K.; Voss, C.; Huebner, G. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic)); Weber, A. (Ernst-Moritz-Arndt-Universitaet, Greifswald (German Democratic Republic). Radiologische Klinik)

    1985-04-01

    The distribution of /sup 125/I-thyroxine (% dose/g tissue; tissue/plasma radioactivity ratio) was investigated in different tissues of 28-week-old obese Wistar rats. Obesity was induced by high-fat diet (HFD) and confirmed by carcass analysis; in heavy obese animals the relative and absolute fat content is increased twofold and threefold, respectively, compared to control rats fed on a low-fat diet (LFD). Heavy HFD rats exhibit diminished /sup 125/I-T/sub 4/ distribution in the 'slow pool' (fat tissue, muscle) and unchanged values in the 'fast pool' (liver, kidneys) in comparison with LFD rats with low body weight. The differences in distribution presented here are not caused by the diet per se, but they are the consequence of the obesity of the animal, because no differences in the /sup 125/I-T/sub 4/ distribution were found in the /sup 125/I-T/sub 4/ between HFD and LFD rats with relatively equal body weight and body composition. The reduced T/sub 4/ distribution in the fat tissue of obese rats is discussed in connection with possibly decreased lipolysis in this tissue and possible causal participation in the beginning of obesity.

  2. PROTEOLYTIC REMOVAL OF THE CARBOXYL TERMINUS OF THE T4 GENE 32 HELIX-DESTABILIZING PROTEIN ALTERS THE T4 IN VITRO REPLICATION COMPLEX

    Energy Technology Data Exchange (ETDEWEB)

    Burke, R.L.; Alberts, B.M.; Hosoda, J.

    1980-07-01

    The proteolytic removal of about 60 amino acids from the COOH terminus of the bacteriophage T4 helix-destabilizing protein (gene 32 protein) produces 32*I, a 27,000-dalton fragment which still binds tightly and cooperatively to single-stranded DNA. The substitution of 32*I protein for intact 32 protein in the seven-protein T4 replication complex results in dramatic changes in some of the reactions catalyzed by this in vitro DNA replication system, while leaving others largely unperturbed. (1) Like intact 32 protein, the 32*I protein promotes DNA synthesis by the DNA polymerase when the T4 polymerase accessory proteins (gene 44/62 and 45 proteins) are also present. The host helix-destabilizing protein (Escherichia coli ssb protein) cannot replace the 32*I protein for this synthesis. (2) Unlike intact 32 protein, 32*I protein strongly inhibits DNA synthesis catalyzed by the T4 DNA polymerase alone on a primed single-stranded DNA template. (3) Unlike intact 32 protein, the 32*I protein strongly inhibits RNA primer synthesis catalyzed by the T4 gene 41 and 61 proteins and also reduces the efficiency of RNA primer utilization. As a result, de novo DNA chain starts are blocked completely in the complete T4 replication system, and no lagging strand DNA synthesis occurs. (4) The 32*I protein does not bind to either the T4 DNA polymerase or to the T4 gene 61 protein in the absence of DNA; these associations (detected with intact 32 protein) would therefore appear to be essential for the normal control of 32 protein activity, and to account at least in part for observations 2 and 3, above. We propose that the COOH-terminal domain of intact 32 protein functions to guide its interactions with the T4 DNA polymerase and the T4 gene 61 RNA-priming protein. When this domain is removed, as in 32*I protein, the helix destabilization induced by the protein is controlled inadequately, so that polymerizing enzymes tend to be displaced from the growing 3{prime}-OH end of a

  3. Structure and expression of the human and mouse T4 genes

    International Nuclear Information System (INIS)

    Maddon, P.J.; Molineaux, S.M.; Maddon, D.F.; Zimmerman, K.A.; Godfrey, M.; Alt, F.W.; Chess, L.; Axel, R.

    1987-01-01

    The T4 molecule may serve as a T-cell receptor recognizing molecules on the surface of specific target cells and also serves as the receptor for the human immunodeficiency virus. To define the mechanisms of interaction of T4 with the surface of antigen-presenting cells as well as with human immunodeficiency virus, the authors have further analyzed the sequence, structure, and expression of the human and mouse T4 genes. T4 consists of an extracellular segment comprised of a leader sequence followed by four tandem variable-joining (VJ)-like domains, a transmembrane domain, and A cytoplasmic segment. The structural domains of the T4 protein deduced from amino acid sequence are precisely reflected in the intron-exon organization of the gene. Analysis of the expression of the T4 gene indicates that T4 RNA is expressed not only in T lymphocytes, but in B cells, macrophages, and granulocytes. T4 is also expressed in a developmentally regulated manner in specific regions of the brain. It is, therefore, possible that T4 plays a more general role in mediating cell recognition events that are not restricted to the cellular immune response

  4. Pediatric Reference Intervals for Free Thyroxine and Free Triiodothyronine by Equilibrium Dialysis-Liquid Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    La'ulu, Sonia L; Rasmussen, Kyle J; Straseski, Joely A

    2016-03-05

    Thyroid hormone concentrations fluctuate during growth and development. To accurately diagnose thyroid disease in pediatric patients, reference intervals (RIs) should be established with appropriate age groups from an adequate number of healthy subjects using the most exact methods possible. Obtaining statistically useful numbers of healthy patients is particularly challenging for pediatric populations. The objective of this study was to determine non-parametric RIs for free thyroxine (fT4) and free triiodothyronine (fT3) using equilibrium dialysis-high performance liquid chromatography-tandem mass spectrometry with over 2200 healthy children 6 months-17 years of age. Subjects were negative for both thyroglobulin and thyroid peroxidase autoantibodies and had normal thyrotropin concentrations. The study included 2213 children (1129 boys and 1084 girls), with at least 120 subjects (average of 125) from each year of life, except for the 6 month to 1 year age group (n=96). Non-parametric RIs (95th percentile) for fT4 were: 18.0-34.7 pmol/L (boys and girls, 6 months-6 years) and 14.2-25.7 pmol/L (boys and girls, 7-17 years). RIs for fT3 were: 5.8-13.1 pmol/L (girls, 6 months-6 years); 5.7-11.8 pmol/L (boys, 6 months-6 years); 5.7-10.0 pmol/L (boys and girls, 7-12 years); 4.5-8.6 pmol/L (girls, 13-17 years); and 5.2-9.4 pmol/L (boys, 13-17 years). Numerous significant differences were observed between pediatric age groups and previously established adult ranges. This emphasizes the need for well-characterized RIs for thyroid hormones in the pediatric population.

  5. A simple ligand-binding assay for thyroxine-binding globulin on reusable Sephadex columns

    International Nuclear Information System (INIS)

    Bastomsky, C.H.; Kalloo, H.; Frenkel-Leith, D.B.; McGill Univ., Montreal, Quebec

    1977-01-01

    A method for the assay of thyroxine-binding globulin on reusable Sephadex G-25 columns is described. It depends upon elution by diluted iodothyronine-free serum of protein-bound [ 125 I]thyroxine from the columns under conditions where binding to thyroxine-binding prealbumin and albumin are abolished. It is simple, rapid and precise, and permits determinations inlarge numbers of samples. Values (mg/l; mean +- S.D.) were: normals 31.6+-5.4, hyperthyroid 28.3+-4.8, hypothyroid 40.6+-7.5, oral contraceptives 40.1+-6.8, pregnant 50.3+-5.4, cirrhotics 20.7+-4.3. Concentrations were reduced in serum heated at 56degC, while the uptake of [ 125 I]triiodothyronine was increased. There was a significant negative correlation between thyroxine-binding globulin concentration and triiodothyronine uptake in the heated serum samples and in euthyroid subjects

  6. Results of surgical treatment of T4 non-small cell lung cancer

    NARCIS (Netherlands)

    Pitz, CCM; de la Riviere, AB; van Swieten, HA; Westermann, CJJ; Lammers, JWJ; van den Bosch, JMM

    2003-01-01

    Objective: Because of location and invasion of surrounding structures, the role of surgical treatment for T4 tumors remains unclear. Extended resections carry a high mortality and should be restricted for selected patients. This study clarifies the selection process in non-small cell T4 tumors with

  7. Assembly and dynamics of the bacteriophage T4 homologous recombination machinery

    Directory of Open Access Journals (Sweden)

    Morrical Scott W

    2010-12-01

    Full Text Available Abstract Homologous recombination (HR, a process involving the physical exchange of strands between homologous or nearly homologous DNA molecules, is critical for maintaining the genetic diversity and genome stability of species. Bacteriophage T4 is one of the classic systems for studies of homologous recombination. T4 uses HR for high-frequency genetic exchanges, for homology-directed DNA repair (HDR processes including DNA double-strand break repair, and for the initiation of DNA replication (RDR. T4 recombination proteins are expressed at high levels during T4 infection in E. coli, and share strong sequence, structural, and/or functional conservation with their counterparts in cellular organisms. Biochemical studies of T4 recombination have provided key insights on DNA strand exchange mechanisms, on the structure and function of recombination proteins, and on the coordination of recombination and DNA synthesis activities during RDR and HDR. Recent years have seen the development of detailed biochemical models for the assembly and dynamics of presynaptic filaments in the T4 recombination system, for the atomic structure of T4 UvsX recombinase, and for the roles of DNA helicases in T4 recombination. The goal of this chapter is to review these recent advances and their implications for HR and HDR mechanisms in all organisms.

  8. Modelling T4 cell count as a marker of HIV progression in the ...

    African Journals Online (AJOL)

    Modelling T4 cell count as a marker of HIV progression in the absence of any defense mechanism. VSM Yadavalli, MMO Labeodan, S Udayabaskaran, N Forche. Abstract. The T4 cell count, which is considered one of the markers of disease progression in an HIV infected individual, is modelled in this paper. The World ...

  9. Specific action of T4 endonuclease V on damaged DNA in xeroderma pigmentosum cells in vivo

    International Nuclear Information System (INIS)

    Tanaka, K.; Hayakawa, H.; Sekiguchi, M.; Okada, Y.

    1977-01-01

    The specific action of T4 endonuclease V on damaged DNA in xeroderma pigmentosum cells was examined using an in vivo assay system with hemagglutinating virus of Japan (Sendai virus) inactivated by uv light. A clear dose response was observed between the level of uv-induced unscheduled DNA synthesis of xeroderma pigmentosum cells and the amount of T4 endonuclease V activity added. The T4 enzyme was unstable in human cells, and its half-life was 3 hr. Fractions derived from an extract of Escherichia coli infected with T4v 1 , a mutant defective in the endonuclease V gene, showed no ability to restore the uv-induced unscheduled DNA synthesis of xeroderma pigmentosum cells. However, fractions derived from an extract of T4D-infected E. coli with endonuclease V activity were effective. The T4 enzyme was effective in xeroderma pigmentosum cells on DNA damaged by uv light but not in cells damaged by 4-nitroquinoline 1-oxide. The results of these experiments show that the T4 enzyme has a specific action on human cell DNA in vivo. Treatment with the T4 enzyme increased the survival of group A xeroderma pigmentosum cells after uv irradiation

  10. [POSSIBLE CAUSES OF INEFFICIENT MONOTHERAPY OF SUBCLINICAL HYPOTHYROIDISM WITH L-THYROXIN].

    Science.gov (United States)

    Budnevsky, A V; Kravchenko, A Ya; Drobysheva, E S; Fes'kova, A A

    2015-01-01

    Substitution therapy with L-thyroxin was recognized in 2012 to be the method of choice for the treatment of subclinical hypothyroidism. However it does not always allow to achieve normalization of all metabolic parameters. The aim of our work was to search for and analyze data on the possible mechanisms responsible for the failure of replacement hormonal therapy with L-thyroxin with a view to changing the therapeutic strategy for patients with subclinical hypothyroidism.

  11. Effects of 5,5'-diphenylhydantoin on thyroxine and 3,5,3'-triiodothyronine concentrations in several tissues of the rat

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder-van der Elst, J.Pv.; van der Heide, D. (University Hospital, Leiden (Netherlands))

    1990-01-01

    We studied the effect of 5,5'-diphenylhydantoin (phenytoin, DPH) on the metabolism of thyroid hormones, the intracellular concentration of T4, and the source and concentration of T3. Two groups of six male Wistar rats received a continuous infusion of 10 ml saline/rat. day. One group received DPH in their food (50 mg/kg BW) for 20 days. For both groups (125I)T4 and (131I)T3 were added to the infusion fluid for the last 10 and 7 days, respectively. At isotopic equilibrium the rats were bled and perfused. Compared to the controls, plasma T4 and T3 in the DPH group were reduced (22% and 31%, respectively); TSH did not change. The rate of production of T4 and the plasma appearance rate for T3 were decreased. Thyroidal T3 production was markedly reduced. From the increased (125I)T3/(125I)T4 ratio for plasma, it follows that total body conversion was enhanced. The tissue T4 concentrations decreased in parallel with the plasma T4 level. Total T3 was reduced in all organs. In tissues in which local conversion does not occur, i.e. heart and muscle, the decrease reflected the decrease in plasma T3. In the liver both plasma-derived T3 and locally produced T3 were diminished. In cerebellum and brain the plasma-derived T3 pool was even smaller than was expected from the decrease in plasma T3. This was partly compensated by an increase in local conversion. Only for these two organs was the decrease in the tissue/plasma ratio for (131I)T3 significant. Our results suggest tissue hypothyroidism, caused by a decrease in the production of T4 and T3, which is partly compensated by increased conversion in several organs. The transport of T3 into cerebellum and brain is disturbed, which can be attributed to the mode of action of DPH.

  12. Effects of 5,5'-diphenylhydantoin on thyroxine and 3,5,3'-triiodothyronine concentrations in several tissues of the rat

    International Nuclear Information System (INIS)

    Schroeder-van der Elst, J.Pv.; van der Heide, D.

    1990-01-01

    We studied the effect of 5,5'-diphenylhydantoin (phenytoin, DPH) on the metabolism of thyroid hormones, the intracellular concentration of T4, and the source and concentration of T3. Two groups of six male Wistar rats received a continuous infusion of 10 ml saline/rat. day. One group received DPH in their food (50 mg/kg BW) for 20 days. For both groups [125I]T4 and [131I]T3 were added to the infusion fluid for the last 10 and 7 days, respectively. At isotopic equilibrium the rats were bled and perfused. Compared to the controls, plasma T4 and T3 in the DPH group were reduced (22% and 31%, respectively); TSH did not change. The rate of production of T4 and the plasma appearance rate for T3 were decreased. Thyroidal T3 production was markedly reduced. From the increased [125I]T3/[125I]T4 ratio for plasma, it follows that total body conversion was enhanced. The tissue T4 concentrations decreased in parallel with the plasma T4 level. Total T3 was reduced in all organs. In tissues in which local conversion does not occur, i.e. heart and muscle, the decrease reflected the decrease in plasma T3. In the liver both plasma-derived T3 and locally produced T3 were diminished. In cerebellum and brain the plasma-derived T3 pool was even smaller than was expected from the decrease in plasma T3. This was partly compensated by an increase in local conversion. Only for these two organs was the decrease in the tissue/plasma ratio for [131I]T3 significant. Our results suggest tissue hypothyroidism, caused by a decrease in the production of T4 and T3, which is partly compensated by increased conversion in several organs. The transport of T3 into cerebellum and brain is disturbed, which can be attributed to the mode of action of DPH

  13. AtlasT4SS: a curated database for type IV secretion systems.

    Science.gov (United States)

    Souza, Rangel C; del Rosario Quispe Saji, Guadalupe; Costa, Maiana O C; Netto, Diogo S; Lima, Nicholas C B; Klein, Cecília C; Vasconcelos, Ana Tereza R; Nicolás, Marisa F

    2012-08-09

    The type IV secretion system (T4SS) can be classified as a large family of macromolecule transporter systems, divided into three recognized sub-families, according to the well-known functions. The major sub-family is the conjugation system, which allows transfer of genetic material, such as a nucleoprotein, via cell contact among bacteria. Also, the conjugation system can transfer genetic material from bacteria to eukaryotic cells; such is the case with the T-DNA transfer of Agrobacterium tumefaciens to host plant cells. The system of effector protein transport constitutes the second sub-family, and the third one corresponds to the DNA uptake/release system. Genome analyses have revealed numerous T4SS in Bacteria and Archaea. The purpose of this work was to organize, classify, and integrate the T4SS data into a single database, called AtlasT4SS - the first public database devoted exclusively to this prokaryotic secretion system. The AtlasT4SS is a manual curated database that describes a large number of proteins related to the type IV secretion system reported so far in Gram-negative and Gram-positive bacteria, as well as in Archaea. The database was created using the RDBMS MySQL and the Catalyst Framework based in the Perl programming language and using the Model-View-Controller (MVC) design pattern for Web. The current version holds a comprehensive collection of 1,617 T4SS proteins from 58 Bacteria (49 Gram-negative and 9 Gram-Positive), one Archaea and 11 plasmids. By applying the bi-directional best hit (BBH) relationship in pairwise genome comparison, it was possible to obtain a core set of 134 clusters of orthologous genes encoding T4SS proteins. In our database we present one way of classifying orthologous groups of T4SSs in a hierarchical classification scheme with three levels. The first level comprises four classes that are based on the organization of genetic determinants, shared homologies, and evolutionary relationships: (i) F-T4SS, (ii) P-T4SS, (iii

  14. The relationship between thyroxine secretion rate and egg production in chicken

    International Nuclear Information System (INIS)

    Sri Asminah; Soewarsono, M.; Djojosoebagio, S.

    1976-01-01

    An experiment was carried out in 24 female White Leghorn Chickens by using 131 I as tracer. The chickens were initially and intraperitoneally injected with 10μCi of 131 I and then counted by means of a Gamma Well Type Scintillation Counter every 48 hours. A dose of 0,3 μg of thyroxine per 100 gr body weight was given as the first administration. After every two administrations of similar dose, the dose of the thyroxine was increased by 0,1 μg/100g body weight until the thyroxine secretion rate was reached. The injections were given in the neck region subcutaneously. The thyroxine secretion rate was found to be within the range from 0,5μg to 0,8μg per 100 g body weight. It also showed that the higher the thyroxine secretion rate, the higher the egg production became. This phenomenon occured both with the 7 and 9 months old chickens. However there was neither ralationship between the thyroxine secretion rate and the weight of eggs produced nor with the body weight of the chickens themselves. (author)

  15. Contribution of local thyroxine monodeiodination to intracellular 3,5, 3'-triiodothyronine in several tissues of hyperthyroid rats at isotopic equilibrium

    International Nuclear Information System (INIS)

    van Doorn, J.; van der Heide, D.; Roelfsema, F.

    1984-01-01

    The local conversion of T4 as a source of intracellular T3 in several organs of both hypothyroid and euthyroid rats has recently been recognized to be an important phenomenon. In the present study the source and quantity of T3 in various peripheral tissues of hyperthyroid rats were investigated. Athyreotic rats received a continuous iv infusion of T4 over a prolonged period in order to attain hyperthyroid conditions. At the same time, the animals also received a continuous iv infusion of [ 125 I]T4 and [ 131 I]T3 until isotopic equilibrium was achieved. After the animals were bled and perfused, the source and quantity of T3 in various tissue homogenates and subcellular preparations of liver, kidney, and the anterior pituitary gland were analyzed. In spite of the elevated plasma T3 and T4 levels, the concentration of T3 in the cerebral cortex and cerebellum was within the normal range. The contribution of T3 derived from local T4 to T3 conversion [Lc T3(T4)] was rather low in both parts of the brain when compared with values previously determined for euthyroid rats. Whereas previous studies revealed that Lc T3(T4) contributes significantly to the T3 in the pituitary glands of both hypothyroid and euthyroid rats, this was not the case for the hyperthyroid animals; virtually all T3 was derived from plasma. It was found that the T3 in muscle was derived exclusively from plasma. Both the liver and kidney showed high concentrations of T3. Whereas Lc T3(T4) was the main source of T3 in the liver, it contributed only a minor fraction of the total T3 content in the kidney

  16. Contribution of local thyroxine monodeiodination to intracellular 3,5, 3'-triiodothyronine in several tissues of hyperthyroid rats at isotopic equilibrium

    Energy Technology Data Exchange (ETDEWEB)

    van Doorn, J.; van der Heide, D.; Roelfsema, F.

    1984-07-01

    The local conversion of T4 as a source of intracellular T3 in several organs of both hypothyroid and euthyroid rats has recently been recognized to be an important phenomenon. In the present study the source and quantity of T3 in various peripheral tissues of hyperthyroid rats were investigated. Athyreotic rats received a continuous iv infusion of T4 over a prolonged period in order to attain hyperthyroid conditions. At the same time, the animals also received a continuous iv infusion of (/sup 125/I)T4 and (/sup 131/I)T3 until isotopic equilibrium was achieved. After the animals were bled and perfused, the source and quantity of T3 in various tissue homogenates and subcellular preparations of liver, kidney, and the anterior pituitary gland were analyzed. In spite of the elevated plasma T3 and T4 levels, the concentration of T3 in the cerebral cortex and cerebellum was within the normal range. The contribution of T3 derived from local T4 to T3 conversion (Lc T3(T4)) was rather low in both parts of the brain when compared with values previously determined for euthyroid rats. Whereas previous studies revealed that Lc T3(T4) contributes significantly to the T3 in the pituitary glands of both hypothyroid and euthyroid rats, this was not the case for the hyperthyroid animals; virtually all T3 was derived from plasma. It was found that the T3 in muscle was derived exclusively from plasma. Both the liver and kidney showed high concentrations of T3. Whereas Lc T3(T4) was the main source of T3 in the liver, it contributed only a minor fraction of the total T3 content in the kidney.

  17. Development of reagents for radioimmunoassay of: triiodothyronine, thyroxine and thyrotrophin; Desarrollo de reactivos para el radioinmunoanalisis de: triyodotironina, tiroxina y tirotrofina

    Energy Technology Data Exchange (ETDEWEB)

    Delgado S, B.; Lavalley E, C.; Ruiz J, A.; Garcia F, C.; Zamorano A, F

    1991-12-15

    The radioimmunoassay (RIA) of thyroid hormones it is the but it frequents of all the studies carried out by RIA in the laboratories of Nuclear Medicine, these essays are carried out with imported reagents. In the ININ the reagents and the necessary methodology have been developed for the triiodothyronine (T3), thyroxine (T4) and thyrotrophin (TSH). The good titles of the antibodies (Ac) primary for each hormone were of 1:4,000; 1:750 and 1:1,500. The used separation system was of double Ac with PEG to 10%, with titles of 1:10 for the second Ac of lamb. The specific activity for 125-I-T3 and 125-I-T4 oscillate between 850 at 900 {mu}Ci / {mu} g: being this of 90 {mu} Ci /{mu}g for TSH. To the first two hormones they were added 1-8 aniline naftalen sulfonic acid (ANS) to concentrations of 3 and 2 mg/ml respectively. As buffer for T3 and T4 it was used Tris-HCl pH 8.6 and PBS with normal serum of rabbit (SNC) for TSH. The standards got ready in buffer or free serum of thyroid hormones. The slope of the standard curves varied between -2.3 to -2.7 and the variation intra and inter assay among 4 to 10%. It is had at the moment in the ININ with standardized reagents for the RIA of T3, T4 and TSH, it is hoped to carry out tests in other laboratories and to establish the conditions of stability more appropriate to begin the preparation of pilot reagents. (Author)

  18. Thyroid stimulating hormone and serum, plasma, and platelet brain-derived neurotrophic factor during a 3-month follow-up in patients with major depressive disorder.

    Science.gov (United States)

    Baek, Ji Hyun; Kang, Eun-Suk; Fava, Maurizio; Mischoulon, David; Nierenberg, Andrew A; Lee, Dongsoo; Heo, Jung-Yoon; Jeon, Hong Jin

    2014-12-01

    Thyroid dysfunction and elevated thyroid stimulating hormone (TSH) are common in patients with depression. TSH might exert its function in the brain through blood levels of brain-derived neurotrophic factor (BDNF). BDNF decreases during depressed states and normalize after treatment. The gap is that the association between TSH and BDNF in patients with major depressive disorder (MDD) is unknown. We studied 105 subjects ≥18 years of age with MDD and measured serum, plasma, and platelet BDNF at baseline, 1 month and 3 months during antidepressant treatment. Other baseline measurements included hypothalamic-pituitary-thyroid axis hormones such as TSH, triiodothyronine (T3) and thyroxine (T4); hypothalamic-pituitary-adrenal (HPA) axis hormones and hypothalamic-pituitary-gonadal (HPG) axis hormones and prolactin. Linear mixed model effect analyses revealed that baseline TSH level was negatively associated with changes of serum BDNF from baseline to 3 months (F=7.58, p=0.007) after adjusting for age, sex, and body mass index, but was not associated with plasma and platelet BDNF. In contrast, T3 and T4, HPA axis hormones, HPG axis hormones, and prolactin were not associated with serum, plasma, or platelet BDNF levels. Patients in the highest quartile of TSH showed significantly lower serum BDNF than in the other quartiles (F=4.54, p=0.038), but no significant differences were found based on T3 and T4 levels. TSH was only measured at baseline. Higher TSH is associated with lower baseline and reduced the increase of serum BDNF levels during antidepressant treatment in patients with MDD. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. The Swelling of Rat Liver Mitochondria by Thyroxine and its Reversal

    Science.gov (United States)

    Lehninger, Albert L.; Ray, Betty Lou; Schneider, Marion

    1959-01-01

    The in vitro swelling action of L-thyroxine on rat liver mitochondria as examined photometrically represents an acceleration of a process which the mitochondria are already inherently capable of undergoing spontaneously, as indicated by the identical kinetic characteristics and the extent of thyroxine-induced and spontaneous swelling, the nearly identical pH dependence, and the fact that sucrose has a specific inhibitory action on both types of swelling. However, thyroxine does not appear to be a "catalyst" or coenzyme since it does not decrease the temperature coefficient of spontaneous swelling. The temperature coefficient is very high, approximately 6.0 near 20°. Aging of mitochondria at 0° causes loss of thyroxine sensitivity which correlates closely with the loss of bound DPN from the mitochondria, but not with loss of activity of the respiratory chain or with the efficiency of oxidative phosphorylation. Tests with various respiratory chain inhibitors showed that the oxidation state of bound DPN may be a major determinant of thyroxine sensitivity; the oxidation state of the other respiratory carriers does not appear to influence sensitivity to thyroxine. These facts and other considerations suggest that a bound form of mitochondrial DPN is the "target" of the action of thyroxine. The thyroxine-induced swelling is not reversed by increasing the osmolar concentration of external sucrose, but can be "passively" or osmotically reversed by adding the high-particle weight solute polyvinylpyrrolidone. The mitochondrial membrane becomes more permeable to sucrose during the swelling reaction. On the other hand, thyroxine-induced swelling can be "actively" reversed by ATP in a medium of 0.15 M KCl or NaCl but not in a 0.30 M sucrose medium. The action of ATP is specific; ADP, Mn++, and ethylenediaminetetraacetate are not active. It is concluded that sucrose is an inhibitor of the enzymatic relationship between oxidative phosphorylation and the contractility and

  20. The Effects of the Recombinant CCR5 T4 Lysozyme Fusion Protein on HIV-1 Infection.

    Directory of Open Access Journals (Sweden)

    Qingwen Jin

    Full Text Available Insertion of T4 lysozyme (T4L into the GPCR successfully enhanced GPCR protein stability and solubilization. However, the biological functions of the recombinant GPCR protein have not been analyzed.We engineered the CCR5-T4L mutant and expressed and purified the soluble recombinant protein using an E.coli expression system. The antiviral effects of this recombinant protein in THP-1 cell lines, primary human macrophages, and PBMCs from different donors were investigated. We also explored the possible mechanisms underlying the observed antiviral effects.Our data showed the biphasic inhibitory and promotion effects of different concentrations of soluble recombinant CCR5-T4L protein on R5 tropic human immunodeficiency virus-1 (HIV-1 infection in THP-1 cell lines, human macrophages, and PBMCs from clinical isolates. We demonstrated that soluble recombinant CCR5-T4L acts as a HIV-1 co-receptor, interacts with wild type CCR5, down-regulates the surface CCR5 expression in human macrophages, and interacts with CCL5 to inhibit macrophage migration. Using binding assays, we further determined that recombinant CCR5-T4L and [125I]-CCL5 compete for the same binding site on wild type CCR5.Our results suggest that recombinant CCR5-T4L protein marginally promotes HIV-1 infection at low concentrations and markedly inhibits infection at higher concentrations. This recombinant protein may be helpful in the future development of anti-HIV-1 therapeutic agents.

  1. T3 may be a better agent than T4 in the critically ill hypothyroid patient: evaluation of transport across the blood-brain barrier in a primate model

    International Nuclear Information System (INIS)

    Chernow, B.; Burman, K.D.; Johnson, D.L.; McGuire, R.A.; O'Brian, J.T.; Wartofsky, L.; Georges, L.P.

    1983-01-01

    Thyroid hormone transport across the blood brain barrier in hypothyroid patients is clinically important yet poorly understood. To study this question, 200 micrograms of thyroxine (T4), 100 micrograms of 3,5,3'-triiodothyronine (T3) and 100 micrograms of 3,3',5'-triiodothyronine (reverse T3) were administered separately to 3 baboons, first iv and at a later date intrathecally (IT). Six animals were used. Three received the iv injections and three received the IT injections. In each of the 18 experiments, cerebrospinal fluid (CSF) and serum specimens were collected serially for 6 h after injection. Mean maximal elevations from baseline in CSF iodothyronine levels were 100 +/- 10 ng/dl after iv T4, 3921 +/- 293 ng/dl after iv T3 and 31 +/- 17 ng/dl after iv reverse T3. When given IT in the same dosages, the mean maximal increases in serum iodothyronine concentrations were: 1670 +/- 600 ng/dl for T4, 806 +/- 405 ng/dl for T3, and 210 +/- 43 ng/dl for reverse T3. In every animal studied, rapid bidirectional transfer of T3 from serum to CSF and CSF to serum occurred, whereas iv T4 resulted in delayed minimal increments in CSF T4 concentration. Isotopic experiments were also performed and the results analyzed using a kinetic model. When 125 I-T3 was given iv, the equilibrium point in CSF was observed within 90 min with 1.7% of the administered dose/L able to be counted in CSF at any moment in time. When labeled T4 was given iv, only 0.6% of the administered dose/L was counted in CSF and the equilibrium point was not reached until 360 min. These data suggest: T4, T3, and reverse T3 are all capable of bidirectional transfer across the blood brain barrier, T3 may be a better agent than T4 in treating patients with myxedema coma because T3 crosses more rapidly and more completely from serum to CSF

  2. Methodological background of the Amersham Amerlex free thyroxine RIA

    International Nuclear Information System (INIS)

    Midgley, J.E.M.

    1982-01-01

    This contribution describes the essential rules underlying a valid estimation of FT4 and compares the way in which various methods deviate from ideal behaviour. The Amerlexsup((R)) FT4RIA test has been validated by several approaches. A practical demonstration of the ability of various methods to correct for differences in T4-binding protein concentration has been made by independent studies in a UK hospital on euthyroid non-pregnant, euthyroid contraceptive and euthyroid pregnant women. The Amersham kit has been shown to correspond closely to theoretical expectations for FT4 values in these groups. (orig.) [de

  3. First experiences with the AMERLEX-MAB FREE T4 assay

    International Nuclear Information System (INIS)

    Nijhof, W.A.; Penders, T.J.

    1989-01-01

    The new Amerlex-MAB FT 4 is a quick direct free T 4 assay with good reproducability. The correlation between the Amerlex-MAB FT 4 and the free T 4 of Byk is good. In the non-thyreoidal illness patient group no deviation for the values were found. Amerlex-MAB FT 4 is cheaper, because no total T4 has to be measured. More research has to be done for special patient sera. Disturbing influences as free fatty acids, heparin and auto-antibodies have to be checked. (R.B.). 3 refs.; 3 figs.; 4 tabs

  4. Treatment of subclinical hypothyroidism in pregnancy using fixed thyroxine daily doses of 75 μg.

    Science.gov (United States)

    Penin, Manuel; Trigo, Cristina; López, Yolanda; Barragáns, María

    2014-01-01

    Treatment of hypothyroid pregnant women is usually calculated based on weight (1 μg/kg/day) and TSH levels. This study assessed the usefulness of treating these women with a fixed dose of 75 μg/day. All women with pregnancy diagnosed from January to August 2012 in the Vigo Health Area (Spain) without previous diagnosis of thyroid disease or thyroxine treatment and with TSH levels over 4,5 mUI/ml were enrolled by consecutive sampling. All 116 women in the sample were treated with a fixed daily dose of thyroxine 75 μg-thyroxine levels were measured at two, four, and six months, and thyroxine dose was modified if TSH level was lower than 0.3 or higher than 4.5 mUI/ml. A woman had a TSH level less than 0.3 mUI/ml in a test; reduction of thyroxine dose to 50 μg/day allowed for maintaining TSH level within the desired range until delivery. Six women had TSH levels over 4.5 mUI/ml in one test; in all of them, increase in thyroxine dose to 100 μg/day allowed for maintaining the level within the desired range until delivery. Fixed daily doses of thyroxine 75 μg allowed for achieving goal TSH levels in most of our pregnant women with subclinical hypothyroidism, irrespective of their weight and baseline TSH level. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.

  5. The direct measurement of free T4 in the eluate of dried blood. Usefulness as a confirmatory screening test for neonatal hypothyroidism

    International Nuclear Information System (INIS)

    Travert, G.; Lemonnier, F.; Fernandez, Y.

    1984-01-01

    In France neonatal screening for hypothyroidism is performed by mean of radioimmunoassay for TSH in dried blood spots, collected on the 5th day of life. In order to be able to get more data from the day 5 blood sample and thus confirm congenital hypothyroidism in all cases when elevated TSH levels have been found, we developed a simple radioimmunoassay for free T4 in eluates of dried blood spots on filter paper. We used reagents from the Amerlex FT4 RIA kit. The ready for use supplied anti-T4 antibody suspension and 125 I-T4 derivative solution are respectively 2-fold and 3-fold diluted in 0,154 M phosphate saline buffer-pH 7,4. Whole blood free T4 standards are prepared by adding serum standards in the kit to an equal volume of washed and packed red blood cells. Free T4 concentrations in these dried standards are expressed as picomoles per liter of whole blood. One blood spot 4.25 mm in diameter, equivalent to about 5-6 μl test blood or standard is incubated for 1 hour at room temperature in 500 μl of antibody suspension. The assay sensitivity (smallest detectable FT4 level) is 1.4 pmol.l -1 . Within assay and between assays coefficients of variation are respectively 9,5 and 13%. Free T4 levels measured in eluates of dried blood closely correlate (r=0,946) with plasma levels in the same subjects. Free T4 in 690 five day old neonates shows a non gaussian distribution, with a mean value: 13,6 pmol.l -1 and standard deviation: 4,3 (range 3,6-30 pmol.l -1 ). In 13 newborns with congenital hypothyroidism, day 5 free T4 levels were found within the range: 0 to 3,5 pmol.l -1 , and thus did not overlap with free T4 measured in age-matched euthyroid neonates [fr

  6. Activity-based in vitro selection of T4 DNA ligase

    International Nuclear Information System (INIS)

    Takahashi, Fumio; Funabashi, Hisakage; Mie, Masayasu; Endo, Yaeta; Sawasaki, Tatsuya; Aizawa, Masuo; Kobatake, Eiry

    2005-01-01

    Recent in vitro methodologies for selection and directed evolution of proteins have concentrated not only on proteins with affinity such as single-chain antibody but also on enzymes. We developed a display technology for selection of T4 DNA ligase on ribosome because an in vitro selection method for DNA ligase had never been developed. The 3' end of mRNA encoding the gene of active or inactive T4 DNA ligase-spacer peptide fusion protein was hybridized to dsDNA fragments with cohesive ends, the substrate of T4 DNA ligase. After in vitro translation of the mRNA-dsDNA complex in a rabbit reticulocyte system, a mRNA-dsDNA-ribosome-ligase complex was produced. T4 DNA ligase enzyme displayed on a ribosome, through addition of a spacer peptide, is able to react with dsDNA in the complex. The complex expressing active ligase was biotinylated by ligation with another biotinylated dsDNA probe and selected with streptavidin-coated magnetic beads. We effectively selected active T4 DNA ligase from a small amount of protein. The gene of the active T4 DNA ligase was enriched 40 times from a mixture of active and inactive genes using this selection strategy. This ribosomal display strategy may have high potential to be useful for selection of other enzymes associated with DNA

  7. Benefit of adjuvant chemotherapy in patients with T4 UICC II colon cancer.

    Science.gov (United States)

    Teufel, Andreas; Gerken, Michael; Hartl, Janine; Itzel, Timo; Fichtner-Feigl, Stefan; Stroszczynski, Christian; Schlitt, Hans Jürgen; Hofstädter, Ferdinand; Klinkhammer-Schalke, Monika

    2015-05-20

    Colorectal cancer is the third most common cancer and a major cause of morbidity and mortality worldwide. Adjuvant chemotherapy is considered the standard of care in patients with UICC stage III colon cancer after R0 resection. Adjuvant therapy was not shown to be beneficial in patients with UICC stage II colon cancer. However, there is an ongoing discussion as to whether adjuvant chemotherapy may be beneficial for a subgroup of UICC II patients in a "high-risk situation" (such as T4). We investigated a Bavarian population-based (2.1 million inhabitants) cohort of 1937 patients with UICC II CRC treated between 2002 and 2012 in regard of the benefit of adjuvant chemotherapy for large (T4) tumors. Patients older than 80 years of age were excluded. Of 1937 patients, 240 had a T4 tumor (12%); 77 of all T4 patients received postoperative chemotherapy (33%). Kaplan-Meier analysis and Cox regression models were used for survival analyses. Patients with a T4 tumor who received postoperative chemotherapy had a highly significant survival benefit in respect of overall survival (pbenefit from adjuvant treatment. Chemotherapy, age at diagnosis, and tumor grading remained independent risk factors in the multivariate cox regression analysis. Our retrospective study demonstrated the significant benefit of adjuvant chemotherapy in the T4 subgroup of patients with UICC II colon cancer. Our data suggest that adjuvant chemotherapy should be seriously considered in these patients.

  8. Radioimmunossay methods for the determination of L-triiodothyronine and thyroxine

    International Nuclear Information System (INIS)

    Margherita, S.S.

    1978-01-01

    An improved, simplified radioimmunoassay method for the in vitro determination of L-triiodothyronine in unextracted blood serum involves the use of a combination reagent constituted by a buffered solution containing radioactive L-triiodothyronine and an inhibitor for inhibiting binding of L-triiodothyronine to thyroxine-binding globulin. Optionally the reagent may also include an antiserum containing antibody capable of immunoreactivity with L-triiodothyronine. Packaged test kits for use in conveniently carrying out the radioimmunoassay are also provided. Certain salts of 8-anilino-1-naphthalene sulfonic acid, which may be regarded as purified forms of the acid, which may be regarded as purified forms of the acid, are preferably employed as inhibitors for inhibiting binding of L-triiodothyronine to thyroxine-binding globulin. An improved radioimmunoassay method for the in vitro determination of thyroxine in unextracted blood serum is characterized by the use of an antiserum containing antibody capable of immunoreactivity with thyroxine and prepared from an immunogen comprising a conjugate of the N-acetyl derivative of thyroxine coupled to bovine serum albumin with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide

  9. Inositol and hepatic lipidosis. II. Effect of inositol supplementation and time from parturition on serum insulin, thyroxine and triiodothyronine and their relationship to serum and liver lipids in dairy cows.

    Science.gov (United States)

    Gerloff, B J; Herdt, T H; Wells, W W; Nachreiner, R F; Emery, R S

    1986-06-01

    Percutaneous liver biopsies and blood samples were obtained from 80 dairy cows in nine Michigan herds over the peripartum period. Thirty-nine cows were fed 17 g of supplemental inositol and 41 were fed a placebo. Liver biopsies were assayed for total myoinositol and triglyceride (TG) concentrations. Blood samples were assayed for serum dextran precipitable cholesterol, nonesterified fatty acids (NEFA), insulin, thyroxine (T4), free (FT4), triiodothyronine (T3) and free T3 (FT3) concentrations. Serum concentrations of insulin and the thyroid hormones decreased near parturition, with lowest concentrations occurring in the immediate postpartum period. Concentrations of T3 correlated well with T4, and the concentrations of free thyroid hormones reflected concentrations of total thyroid hormones. The percentage of hormone in the free fraction remained constant over time. Serum insulin, T3 and T4 were negatively correlated with serum NEFA and liver TG concentrations. Thyroid hormone concentrations were positively correlated with serum dextran precipitable cholesterol concentrations. Inositol supplementation was associated with reduced circulating T3 and FT3 concentrations, but not T4 and FT4 concentrations. Changes in hormone concentrations at parturition and their relationship to liver TG and serum NEFA concentrations were consistent with a metabolic adaptation by the dairy cow to the negative energy balance of early lactation.

  10. Pediatric Reference Intervals for Free Thyroxine and Free Triiodothyronine

    Science.gov (United States)

    Jang, Megan; Guo, Tiedong; Soldin, Steven J.

    2009-01-01

    Background The clinical value of free thyroxine (FT4) and free triiodothyronine (FT3) analysis depends on the reference intervals with which they are compared. We determined age- and sex-specific reference intervals for neonates, infants, and children 0–18 years of age for FT4 and FT3 using tandem mass spectrometry. Methods Reference intervals were calculated for serum FT4 (n = 1426) and FT3 (n = 1107) obtained from healthy children between January 1, 2008, and June 30, 2008, from Children's National Medical Center and Georgetown University Medical Center Bioanalytical Core Laboratory, Washington, DC. Serum samples were analyzed using isotope dilution liquid chromatography tandem mass spectrometry (LC/MS/MS) with deuterium-labeled internal standards. Results FT4 reference intervals were very similar for males and females of all ages and ranged between 1.3 and 2.4 ng/dL for children 1 to 18 years old. FT4 reference intervals for 1- to 12-month-old infants were 1.3–2.8 ng/dL. These 2.5 to 97.5 percentile intervals were much tighter than reference intervals obtained using immunoassay platforms 0.48–2.78 ng/dL for males and 0.85–2.09 ng/dL for females. Similarly, FT3 intervals were consistent and similar for males and females and for all ages, ranging between 1.5 pg/mL and approximately 6.0 pg/mL for children 1 month of age to 18 years old. Conclusions This is the first study to provide pediatric reference intervals of FT4 and FT3 for children from birth to 18 years of age using LC/MS/MS. Analysis using LC/MS/MS provides more specific quantification of thyroid hormones. A comparison of the ultrafiltration tandem mass spectrometric method with equilibrium dialysis showed very good correlation. PMID:19583487

  11. The E. coli Global Regulator DksA Reduces Transcription during T4 Infection

    Directory of Open Access Journals (Sweden)

    Jennifer Patterson-West

    2018-06-01

    Full Text Available Bacteriophage T4 relies on host RNA polymerase to transcribe three promoter classes: early (Pe, requires no viral factors, middle (Pm, requires early proteins MotA and AsiA, and late (Pl, requires middle proteins gp55, gp33, and gp45. Using primer extension, RNA-seq, RT-qPCR, single bursts, and a semi-automated method to document plaque size, we investigated how deletion of DksA or ppGpp, two E. coli global transcription regulators, affects T4 infection. Both ppGpp0 and ΔdksA increase T4 wild type (wt plaque size. However, ppGpp0 does not significantly alter burst size or latent period, and only modestly affects T4 transcript abundance, while ΔdksA increases burst size (2-fold without affecting latent period and increases the levels of several Pe transcripts at 5 min post-infection. In a T4motAam infection, ΔdksA increases plaque size and shortens latent period, and the levels of specific middle RNAs increase due to more transcription from Pe’s that extend into these middle genes. We conclude that DksA lowers T4 early gene expression. Consequently, ΔdksA results in a more productive wt infection and ameliorates the poor expression of middle genes in a T4motAam infection. As DksA does not inhibit Pe transcription in vitro, regulation may be indirect or perhaps requires additional factors.

  12. Combination L-T3 and L-T4 therapy for hypothyroidism.

    Science.gov (United States)

    Wartofsky, Leonard

    2013-10-01

    Because of the longstanding controversy regarding whether hypothyroid patients can be optimally replaced by treatment with levothyroxine (L-T4) alone, numerous studies have addressed potential benefits of combined therapy of triiodothyronine (T3) with L-T4. Results of these studies have failed to support a potential benefit of combined therapy. A strong argument for the addition of L-T3 to L-T4 monotherapy has been lacking until recent genetic studies indicated a rationale for such therapy among a small fraction of the hypothyroid patient population. Interest in this issue has focused on the importance of the deiodinases in maintaining the euthyroid state and the role of genetic polymorphisms in the deiodinase genes that would affect thyroid hormone concentrations in both blood and tissues. One such polymorphism in the D2 gene, Thr92Ala, is associated with reduced T4 to T3 activation in skeletal muscle and thyroid, linked to obesity and alterations in thyroid-pituitary feedback, and in responses to thyroid hormone treatment. Although our professional organizations continue to recommend L-T4 alone for the treatment of hypothyroidism, the possibility of a D2 gene polymorphism should be considered in patients on L-T4 monotherapy who continue to complain of fatigue in spite of dosage achieving low normal serum thyroid stimulating hormone levels. A suggestive clue to the presence of this polymorphism could be a higher than normal free T4/free T3 ratio. Clinicians could consider adding T3 as a therapeutic trial in selected patients. Future well controlled clinical trials will be required to more fully resolve the controversy.

  13. Clinicopathological outcomes of preoperative chemoradiotherapy using S-1 plus Irinotecan for T4 lower rectal cancer.

    Science.gov (United States)

    Beppu, Naohito; Yoshie, Hidenori; Kimura, Fumihiko; Aihara, Tsukasa; Doi, Hiroshi; Kamikonya, Norihiko; Matsubara, Nagahide; Tomita, Naohiro; Yanagi, Hidenori; Yamanaka, Naoki

    2016-07-01

    To investigate the clinicopathological outcomes of patients with T4 lower rectal cancer treated using preoperative chemoradiotherapy with S-1 plus Irinotecan. Between 2005 and 2011, 35 patients with T4M0 lower rectal cancer, diagnosed initially as T4a in 12 and as T4b in 23, were treated with 45 Gy of radiotherapy concomitantly with S-1 plus Irinotecan. The median follow-up period was 50.6 months (range 2-123 months). A total of 32 patients (91.4 %) completed the radiotherapy and 26 (74.3 %) completed the full chemotherapy regimen. Radical surgery was then performed in 33 (94.3 %) of the 35 patients after the exclusion of two patients, who had macroscopic residual disease. The pathological diagnosis was downstaged from T4a to ypT0-3 in all 12 of those patients (100 %) and from T4b to ypT0-4a in 20 of those 23 patients (87.0 %). The tumor regression grade of 1a/1b/2/3 (complete response) was 10/8/15/2, respectively. In terms of long-term survival, the 5-year local relapse-free survival rate was 74.8 % and the recurrence-free survival rate was 52.0 %. This regimen may result in favorable downstaging. Moreover, in this series, pathological evidence of involvement of adjacent organs was rare following preoperative chemoradiotherapy, in the patients with disease diagnosed as T4b at the initial staging.

  14. Effects of season, pregnancy and lactation on serum thyroxine level in dairy cattle

    Energy Technology Data Exchange (ETDEWEB)

    Shoda, Y [Tokyo Univ. (Japan). Faculty of Agriculture; Ishii, T

    1976-11-01

    Serum thyroxine level was determined monthly for fifteen Holstein cows by radio stereoassay using polyvinyl alcohol (PVF) sponge throughout a year to investigate the effects of season, pregnancy and lactation on the thyroxine level seasonably, the serum thyroxine level was low in summer, and the average level in July and August was 12.6 ..mu..g/dl, which was a half of the average winter level in January and February of 26.2 ..mu..g/dl. It became low level at the late stage of gestation, showing the lowest value of 13.7 ..mu..g/dl just before delivery, and increased suddenly in the second month of lactation attaining the highest level of 27.0 ..mu..g/dl. It reduced slightly thereafter to be 22.1 ..mu..g/dl at the end of lactation.

  15. Effects of season, pregnancy and lactation on serum thyroxine level in dairy cattle

    International Nuclear Information System (INIS)

    Shoda, Yoichi; Ishii, Tadao.

    1976-01-01

    Serum thyroxine level was determined monthly for fifteen Holstein cows by radio stereoassay using polyvinyl alcohol (PVF) sponge throughout a year to investigate the effects of season, pregnancy and lactation on the thyroxine level seasonably, the serum thyroxine level was low in summer, and the average level in July and August was 12.6 μg/dl, which was a half of the average winter level in January and February of 26.2 μg/dl. It became low level at the late stage of gestation, showing the lowest value of 13.7 μg/dl just before delivery, and increased suddenly in the second month of lactation attaining the highest level of 27.0 μg/dl. It reduced slightly thereafter to be 22.1 μg/dl at the end of lactation. (Kobatake, H.)

  16. Method of separating (125I)-L-thyroxine from mixture obtained by radioiodination

    International Nuclear Information System (INIS)

    Mucha, J.; Talan, P.; Dobias, M.

    1982-01-01

    ( 125 I)-L-thyroxine is separated by gel filtration on a column from the mixture of ( 125 I)-L-thyroxine, ( 125 I)-L-3,5,3'-triiodothyronine and ( 125 I) - . The column is packed with a non-polar gel such as polydextran with particle size 25 to 100 μm. The mixture 1,2-propanediol/distilled water/concentrated (26%) aqueous ammonia solution, or 1,2-propanediol/concentrated (26%) aqueous ammonia solution is used as eluent. The concentration of the eluate containing ( 125 I)-L-thyroxine is adjusted with distilled water such as to establish a 50 vol.% concentration of 1,2-propanediol. (E.S.)

  17. Application of 131I- and 125I-thyroxine in research of thyroid activity control

    International Nuclear Information System (INIS)

    Michajlovskij, N.; Langer, P.; Stastna, M.; Gschwendtova, L.; Sadlon, J.

    1974-01-01

    A report is presented on determining the normal levels of free thyroxine and triiodothyronine in the blood sera of man and of animals using tracer techniques with 125 I as a tracer. A method was elaborated of determining thyroxine by equilibrium dialysis and conditions were found of the quantitative chemical analysis of the blood sera of man and of rats for triiodothyronine. A nodification of the method made possible microanalysis of samples smaller than 2 ml, thus permitting the application of the procedure in determining the components in the blood serum of individuals in contrast to the previous practice when only mixtures of blood sera taken from groups of animals could be analyzed. The effect was also studied of certain significant factors, such as anaesthetics and others on the level of free thyroxine in the blood sera of man and of rats. (L.O.)

  18. Restriction of phage T4 internal protein I mutants by a strain of Escherichia coli

    International Nuclear Information System (INIS)

    Black, L.W.; Abremski, K.

    1974-01-01

    Phage T4 internal protein I(IPI), a small (ca, 10,000 MW), basic protein injected into the host with the phage DNA, is not required for infection of most hosts, but mutants defective in IPI are restricted by at least one naturally occurring strain of Escherichia coli, CT 596 (CT). Phages lacking IPI (IPI - ) appear to inject their DNA and bind it to the membrane of CT cells as well as wild-type phage T4 does, but shutoff of host protein synthesis, initiation of T4 protein synthesis, and cell killing are abnormal in the IPI - mutant infected CT host. The injection of IPI appears to be important in allowing T4 DNA to carry out early steps involved in takeover of this host. Restriction of IPI - phage growth by CT cells appears to be due, at least in part, to a defective prophage it harbors which renders the host resistant to successful infection by phage T4 which lack IPI or rII functions. Bacteria cured of this prophage can be infected by mutants defective in these functions. The resistance of CT cells to other coliphages, and the question of T-even phage internal protein diversity are discussed. (U.S.)

  19. Analysis of T4SS-induced signaling by H. pylori using quantitative phosphoproteomics

    Directory of Open Access Journals (Sweden)

    Frithjof eGlowinski

    2014-07-01

    Full Text Available Helicobacter pylori is a Gram-negative bacterial pathogen colonizing the human stomach. Infection with H. pylori causes chronic inflammation of the gastric mucosa and may lead to peptic ulceration and/or gastric cancer. A major virulence determinant of H. pylori is the type IV secretion system (T4SS, which is used to inject the virulence factor CagA into the host cell, triggering a wide range of cellular signaling events. Here, we used a phosphoproteomic approach to investigate tyrosine signaling in response to host-pathogen interaction, using stable isotope labeling in cell culture (SILAC of AGS cells to obtain a differential picture between multiple infection conditions. Cells were infected with wild type H. pylori P12, a P12ΔCagA deletion mutant, and a P12ΔT4SS deletion mutant to compare signaling changes over time and in the absence of CagA or the T4SS. Tryptic peptides were enriched for tyrosine (Tyr phosphopeptides and analysed by nano-LC-Orbitrap MS. In total, 58 different phosphosites were found to be regulated following infection. The majority of phosphosites identified were kinases of the MAPK familiy. CagA and the T4SS were found to be key regulators of Tyr phosphosites. Our findings indicate that CagA primarily induces activation of ERK1 and integrin linked factors, whereas the T4SS primarily modulates JNK and p38 activation.

  20. Performance Evaluation of the MyT4 Technology for Determining ART Eligibility.

    Science.gov (United States)

    Sitoe, Nádia; Macamo, Rosa; Meggi, Bindiya; Tobaiwa, Ocean; Loquiha, Osvaldo; Bollinger, Timothy; Vojnov, Lara; Jani, Ilesh

    2016-01-01

    In resource-limited countries, CD4 T-cell (CD4) testing continues to be used for determining antiretroviral therapy (ART) initiation eligibility and opportunistic infection monitoring. To support expanded access to CD4 testing, simple and robust technologies are necessary. We conducted this study to evaluate the performance of a new Point-of-Care (POC) CD4 technology, the MyT4, compared to conventional laboratory CD4 testing. EDTA venous blood from 200 HIV-positive patients was tested in the laboratory using the MyT4 and BD FACSCalibur™. The MyT4 had an r2 of 0.82 and a mean bias of 12.3 cells/μl. The MyT4 had total misclassifications of 14.7% and 8.8% when analyzed using ART eligibility thresholds of 350 and 500 cells/μl, respectively. We conclude that the MyT4 performed well in classifying patients using the current ART initiation eligibility thresholds in Mozambique when compared to the conventional CD4 technology.

  1. THE DIGESTIVE TRACT DEVELOPMENT OF THE TIGER GROUPER Epinephelus fuscoguttatus LARVAE TREATED WITH THYROXINE HORMONE

    OpenAIRE

    Ahmad Muzaki; Ketut Mahardika; Indah Mastuti; Wawan Andriyanto; Yasmina Nirmala Asih; Ida Komang Wardana

    2012-01-01

    Thyroxin administration in tiger grouper larval rearing was conducted to determine its effect on development of digestive tract of the larvae. Newly hatched larvae were treated with 0 mg/L (control), 0.1 mg/L, and 0.2 mg/L of thyroxin for 2 hours in a 30 L tank before were transferred into a 1 m3 rearing tank. Samples were collected daily until 10 DAH and every 3 days until 40 DAH. Development of digestive tract was observed using histological method. For all treatments, the digestive tract w...

  2. Specific labeling of the thyroxine binding site in thyroxine-binding globulin: determination of the amino acid composition of a labeled peptide fragment isolated from a proteolytic digest of the derivatized protein.

    Science.gov (United States)

    Tabachnick, M; Perret, V

    1987-08-01

    [125I] Thyroxine has been covalently bound to the thyroxine binding site in thyroxine-binding globulin by reaction with the bifunctional reagent, 1,5-difluoro-2,4-dinitrobenzene. An average of 0.47 mol of [125I] thyroxine was incorporated per mol protein; nonspecific binding amounted to 8%. A labeled peptide fragment was isolated from a proteolytic digest of the derivatized protein by HPLC and its amino acid composition was determined. Comparison with the amino acid sequence of thyroxine-binding globulin indicated partial correspondence of the labeled peptide with two possible regions in the protein. These regions also coincide with part of the barrel structure present in the closely homologous protein, alpha 1-antitrypsin.

  3. Median-lower normal levels of serum thyroxine are associated with low triiodothyronine levels and body temperature in patients with central hypothyroidism.

    Science.gov (United States)

    Hirata, Yu; Fukuoka, Hidenori; Iguchi, Genzo; Iwahashi, Yasuyuki; Fujita, Yasunori; Hari, Yusuke; Iga, Makiko; Nakajima, Shinsuke; Nishimoto, Yuki; Mukai, Miki; Hirota, Yushi; Sakaguchi, Kazuhiko; Ogawa, Wataru; Takahashi, Yutaka

    2015-08-01

    Although it has been recommended that serum free thyroxine (FT4) levels should be targeted to middle-upper normal levels during levothyroxine (l-T4) replacement therapy in patients with central hypothyroidism (CeH), the rationale has not been clarified. A retrospective single-center study enrolled 116 patients with hypothyroidism (CeH, n=32; total thyroidectomy (Tx), n=22; primary hypothyroidism (PH), n=33; and control benign thyroid nodule (C), n=29). The patients had received L-T4 therapy at the Kobe University Hospital between 2003 and 2013. They were stratified according to serum FT4 level (≥ 1.10 or triiodothyronine (FT3) levels, FT3/FT4 ratio, and lipid profiles were compared. The effect of GH replacement therapy on thyroid function was also analyzed. FT3 levels and FT3/FT4 ratios were significantly lower in patients with CeH than in patients with PH (P<0.05) or C (P<0.05). In patients with FT4 <1.10 ng/dl, BT was significantly lower in patients with CeH (P=0.002) and Tx (P=0.005) than in patients with PH, whereas no differences were found in patients with FT4 ≥ 1.10 ng/dl. In patients with CeH, FT3 levels were higher in those with GH replacement therapy (P=0.018). In CeH, patients with median-lower normal levels of serum FT4 exhibited lower serum FT3 levels and lower BT. These results support the target levels of serum FT4 as middle-upper normal levels during l-T4 replacement therapy in patients with CeH. © 2015 European Society of Endocrinology.

  4. Free thyroxine by solid phase radioimmunoassay: improvement in the laboratory diagnosis of thyroid status in severely ill patients

    Energy Technology Data Exchange (ETDEWEB)

    Bayer, M.F.; McDougall, I.R. (Stanford Univ., CA (USA). School of Medicine)

    1982-02-05

    During severe systemic illness total thyroid hormone levels are often low, and measurement of total hormones often does not differentiate between euthyroid and hypothyroid patients. Therefore serum free thyroxine levels were tested by radioimmunoassay (antibody-coated tubes, Clinical Assays) as an alternative diagnostic test in three groups of severely ill patients with subnormal triiodothyronine. Free thyroxine estimates agreed with the clinical impression and TSH in 91% of cases in group 1 (47 patients with no history or clinical evidence of thyroid disorder), in 96% of cases in group 2 (24 euthyroid patients with a history of thyroid disease, including some on thyroid replacement) and 90% of cases in group 3 (10 hypothyroid patients). By contrast, the free thyroxine index did so in only 53% (group 1), 46% (group 2) or 100% (group 3). Sequential studies showed little change in free thyroxine and TSH levels in euthyroid patients during illness and recovery, and a good negative correlation between free thyroxine and TSH in hypothyroid patients. Free thyroxine measurements (and TSH) discriminate between euthyroid and hypothyroid sick patients better than other thyroid function tests including the free thyroxine index, and can be employed routinely: a distinct advantage over free thyroxine measured by equilibrium dialysis.

  5. Binding of T4 endonuclease V to deoxyribonucleic acid irradiated with ultraviolet light

    International Nuclear Information System (INIS)

    Seawell, P.C.; Simon, T.J.; Ganesan, A.K.

    1980-01-01

    Endonuclease V of bacteriophage T4 binds to uv-irradiated deoxyribonucleic acid (DNA) but not to unirradiated DNA. We have developed an assay to detect this binding, based on the retention of enzyme - DNA complexes on nitrocellulose filters. The amount of complex retained, ascertained by using radioactive DNA, is a measure of T4 endonuclease V activity. From our data we conclude that (1) T4 endonuclease V binds to uv-irradiated DNA but not to DNA that has been previously incised by the endonuclease, (2) equilibrium between the free and complexed form of the enzyme is attained under our reaction conditions, (3) dissociation of enzyme - DNA complexes is retarded by sodium cyanide, and (4) retention of enzyme - DNA complexes on nitrocellulose filters is enhanced by high concentrations of saline-citrate

  6. Zinc(II) and the single-stranded DNA binding protein of bacteriophage T4

    International Nuclear Information System (INIS)

    Gauss, P.; Krassa, K.B.; McPheeters, D.S.; Nelson, M.A.; Gold, L.

    1987-01-01

    The DNA binding domain of the gene 32 protein of the bacteriophage T4 contains a single zinc-finger sequence. The gene 32 protein is an extensively studied member of a class of proteins that bind relatively nonspecifically to single-stranded DNA. The authors have sequenced and characterized mutations in gene 32 whose defective proteins are activated by increasing the Zn(II) concentration in the growth medium. The results identify a role for the gene 32 protein in activation of T4 late transcription. Several eukaryotic proteins with zinc fingers participate in activation of transcription, and the gene 32 protein of T4 should provide a simple, well-characterized system in which genetics can be utilized to study the role of a zinc finger in nucleic acid binding and gene expression

  7. The effect of L-thyroxine treatment on hypothyroid symptom scores and lipid profile in children with subclinical hypothyroidism.

    Science.gov (United States)

    Çatlı, Gönül; Anık, Ahmet; Ünver Tuhan, Hale; Böber, Ece; Abacı, Ayhan

    2014-12-01

    To evaluate i) the frequency of typical hypothyroidism symptoms in children with subclinical hypothyroidism (SH), ii) to evaluate the association of SH with lipoproteins and iii) to investigate possible improving effects of L-thyroxine (LT4) treatment on these findings. Twenty-seven children with SH who had elevated thyroid-stimulating hormone (TSH: >4.94 µIU/L) but normal free T4 levels and healthy euthyroid children of similar age and sex were enrolled in the study. Anthropometric and laboratory (lipid profile and thyroid function tests) measurements were performed at diagnosis and six months after euthyroidism was achieved. All children were also subjected to a questionnaire on hypothyroid symptoms at diagnosis. The SH patients were subjected to the questionnaire also following treatment. Pre-treatment data were compared with those of controls and post-treatment measurements. Anthropometric and laboratory parameters of the groups were not statistically different except for higher TSH levels in the SH group. Serum lipoprotein levels and dyslipidemia frequency were similar between the groups. Compared to the controls, hypothyroidism symptom score was significantly higher in the SH group. Six months after euthyroidism was achieved, a significant reduction in the hypothyroid symptom score was obtained in the SH group. Except for significantly higher serum TSH values, no significant differences regarding demographic characteristics, symptom scores and lipid parameters were present between patients with Hashimoto's thyroiditis and the remaining SH patients. The results of this study showed that in children with SH i) the hypothyroidism symptom score was significantly higher than in euthyroid children, ii) LT4 treatment improved the hypothyroidism symptom score and iii) SH does not seem to be associated with dyslipidemia.

  8. Comparison of Immunoassay methods for T3, T4 and TSH

    International Nuclear Information System (INIS)

    Alonso Rodríguez, Celia A.

    2016-01-01

    Measurements of T3, T4 and TSH have been considered very important in the diagnosis and monitoring of thyroid diseases both overt and subclinical. These subclinical diseases are actively seeking for years, both in healthy patients and hospitalized for other illnesses; and in the population over 35 years, especially women, in health checkups. The active search for these diseases requires the use of rapid and reliable techniques; that can be developed massively, with good level of detectability and comparable. The overall objective is to present the evaluation of different immunoassay techniques with respect to the RIA and IRMA: ELISA, chemiluminescence, Amplified Chemiluminescence, electrochemiluminescence Immunofluorescence. Compare including automatic methods and analyze the cost and feasibility of them for laboratory immunoassay. ELISA colorimetric technique for dosing was comparable to RIA T4, not for T3. Chemiluminescence (AMERLITE) compared to dosing RIA and IRMA T4 to TSH proved to be valid for both. Amplified Chemiluminescence (Immulite) compared to IRMA for TSH was no significant difference. Electrochemiluminescence (Elecsys 2010) compared to T3 and T4 RIA and IRMA for TSH, no significant differences for T4 and TSH; but no variation to T3. Immunofluorescence (AIA-600) used to compare with RIA for T3 and T4, and TSH IRMA, no significant differences for the measured analytes. Benchmarking of automatic methods suggests that the most thrifty of trials is Immunofluorescence the AIA-600, regarding calibration and control, programming time, randomization and the ability to save the value of the fluorescence deferred calculations for tests without valid at the time of realizing calibration. Analyzing the cost and feasibility of these methods for laboratory immunoassay, we must consider that their characteristics electrochemiluminescence is the fastest, but its price is prohibitive for our health systems. The AIA-600 appears to be the method of choice for its

  9. Benefit of adjuvant chemotherapy in patients with T4 UICC II colon cancer

    International Nuclear Information System (INIS)

    Teufel, Andreas; Gerken, Michael; Hartl, Janine; Itzel, Timo; Fichtner-Feigl, Stefan; Stroszczynski, Christian; Schlitt, Hans Jürgen; Hofstädter, Ferdinand; Klinkhammer-Schalke, Monika

    2015-01-01

    Colorectal cancer is the third most common cancer and a major cause of morbidity and mortality worldwide. Adjuvant chemotherapy is considered the standard of care in patients with UICC stage III colon cancer after R0 resection. Adjuvant therapy was not shown to be beneficial in patients with UICC stage II colon cancer. However, there is an ongoing discussion as to whether adjuvant chemotherapy may be beneficial for a subgroup of UICC II patients in a “high-risk situation” (such as T4). We investigated a Bavarian population-based (2.1 million inhabitants) cohort of 1937 patients with UICC II CRC treated between 2002 and 2012 in regard of the benefit of adjuvant chemotherapy for large (T4) tumors. Patients older than 80 years of age were excluded. Of 1937 patients, 240 had a T4 tumor (12 %); 77 of all T4 patients received postoperative chemotherapy (33 %). Kaplan-Meier analysis and Cox regression models were used for survival analyses. Patients with a T4 tumor who received postoperative chemotherapy had a highly significant survival benefit in respect of overall survival (p < 0.001) and recurrence-free survival (p = 0.008). However, no difference was observed between oxaliplatin-containing and non-oxaliplatin-containing treatment regimens. G2 and G3 tumors were found to particularly benefit from adjuvant treatment. Chemotherapy, age at diagnosis, and tumor grading remained independent risk factors in the multivariate cox regression analysis. Our retrospective study demonstrated the significant benefit of adjuvant chemotherapy in the T4 subgroup of patients with UICC II colon cancer. Our data suggest that adjuvant chemotherapy should be seriously considered in these patients. The online version of this article (doi:10.1186/s12885-015-1404-9) contains supplementary material, which is available to authorized users

  10. Crystal Structure of the Phage T4 Recombinase UvsX and Its Functional Interaction with the T4 SF2 Helicase UvsW

    Energy Technology Data Exchange (ETDEWEB)

    Gajewski, Stefan; Webb, Michael R.; Galkin, Vitold; Egelman, Edward H.; Kreuzer, Kenneth N.; White, Stephen W. (Duke); (UV); (SJCH)

    2012-07-11

    Bacteriophage T4 provides an important model system for studying the mechanism of homologous recombination. We have determined the crystal structure of the T4 UvsX recombinase, and the overall architecture and fold closely resemble those of RecA, including a highly conserved ATP binding site. Based on this new structure, we reanalyzed electron microscopy reconstructions of UvsX-DNA filaments and docked the UvsX crystal structure into two different filament forms: a compressed filament generated in the presence of ADP and an elongated filament generated in the presence of ATP and aluminum fluoride. In these reconstructions, the ATP binding site sits at the protomer interface, as in the RecA filament crystal structure. However, the environment of the ATP binding site is altered in the two filament reconstructions, suggesting that nucleotide cannot be as easily accommodated at the protomer interface of the compressed filament. Finally, we show that the phage helicase UvsW completes the UvsX-promoted strand-exchange reaction, allowing the generation of a simple nicked circular product rather than complex networks of partially exchanged substrates.

  11. Effect of protein and protein-free energy intake on plasma concentrations of insulin-like growth factor I and thyroid hormones in preruminant calves

    NARCIS (Netherlands)

    Gerrits, W.J.J.; Decuypere, E.; Verstegen, M.W.A.; Karabinas, V.

    1998-01-01

    We conducted two experiments with preruminant calves weighing 80 to 240 kg to study the long-term nutritional regulation of circulating IGF-I, thyroxine (T4), and triiodothyronine (T3). The two experiments were similar in design but were performed with calves of two live weight ranges: 80 to 160 kg

  12. Case report: When measured free T4 and free T3 may be misleading. Interference with free thyroid hormones measurements on Roche® and Siemens® platforms

    Directory of Open Access Journals (Sweden)

    Lewandowski Krzysztof C

    2012-10-01

    Full Text Available Abstract A 59-year old female patient presented with apathy and 6 kg weight gain. Investigations revealed severe primary hypothyroidism (TSH>100 μIU/ml. L-thyroxine (L-T4 was started and titrated up to 75 μg, once daily, with clinical improvement. Other investigations revealed very high titres of anti-thyroid peroxidase (anti-TPO and anti-thyroglobulin (anti-Tg antibodies. After three months, there was a fall in TSH to 12.74 μIU/ml, however, with unexpectedly high free T4 (FT4 - 6.8 ng/ml and free T3 (FT3 - 6.7 pg/ml concentrations [reference range (rr: 0.8-1.9 ng/ml and 1.5-4.1 pg/ml (Siemens®, respectively]. At this stage L-T4 was stopped, and this was followed by a rapid increase in TSH (to 77.76 μIU/ml and some decrease in FT4 and FT3, however FT4 concentration remained elevated (2.1 ng/ml. Following this, L-T4 was restarted. On admission to our Department, she was clinically euthyroid on L-T4, 88 μg, once daily. Investigations on Roche® platform confirmed mildly elevated TSH - 5.14 (rr: 0.27-4.2 μIU/ml with high FT4 [4.59 (rr: 0.93-1.7 ng/ml] and FT3 [4.98 (rr: 2.6-4.4 pg/ml] concentrations. Other tests revealed hypoechogenic ultrasound pattern typical for Hashimoto thyroiditis. There was no discrepancy in calculated TSH value following TSH dilution (101% recovery. Concentrations of FT4 and FT3 were assessed on the day of discontinuation of L-T4 and after four days by the means of Abbott® Architect I 1000SR platform. These revealed FT4 and FT3 concentrations within the reference range [e.g., FT4 - 1.08 ng/ml (rr: 0.7-1.48] vs 4.59 ng/ml (rr: 0.93-1.7, Roche®, FT3 - 3.70 pg/ml (rr: 1.71-3.71 vs 4.98 (rr: 2.6-4.4, Roche®], confirming assay interference. Concentrations of ferritin and SHBG were normal. Conclusions Clinicians must be aware of possible assay interference, including the measurements of FT4 and FT3 in the differential diagnosis of abnormal results of thyroid function tests that do not fit the patient clinical

  13. Successful treatment of refractory TAFRO syndrome with elevated vascular endothelial growth factor using thyroxine supplements.

    Science.gov (United States)

    Oka, Satoko; Ono, Kazuo; Nohgawa, Masaharu

    2018-04-01

    Although the clinical significance of hypothyroidism in TAFRO syndrome is unknown, vascular endothelial growth factor (VEGF) levels decreased with improvements in the condition of our refractory TAFRO cases after thyroxine supplement therapy. Our results indicate that elevated VEGF levels are a potential factor in the pathogenesis and anasarca of TAFRO syndrome with hypothyroidism.

  14. Preparation of standards of triiodothyronine, thyroxine and thyrotropin; Prepracion de estandares de triyodotironina, tiroxina y tirotrofina

    Energy Technology Data Exchange (ETDEWEB)

    Lavalley E, C.; Delgado S, B.; Ruiz J, A.; Zambrano A, F

    1991-10-15

    The standards preparation requires of certain basic principles, some of which are described in this work, which was made with the purpose of establishing the most appropriate conditions for the preparation of standards of triiodothyronine, thyroxine and thyrotropin to be used in radioimmunoanalysis essays. The diverse standards show a balanced displacement, that which is observed in the graphs presented in this work. (Author)

  15. Proposal of a candidate international conventional reference measurement procedure for free thyroxine in serum.

    NARCIS (Netherlands)

    Thienpont, L.M.; Beastall, G.H.; Christofides, N.D.; Faix, J.D.; Ieiri, T.; Jarrige, V.; Miller, W.G.; Miller, R.; Nelson, J.C.; Ronin, C.; Ross, H.A.; Rottmann, M.; Thijssen, J.H.; Toussaint, B.

    2007-01-01

    In the present paper the IFCC WG-STFT recommends and provides the rationale to establish metrological traceability of serum free thyroxine (FT4) measurements to a candidate international conventional reference measurement procedure. It is proposed that this procedure be based on equilibrium dialysis

  16. Evaluation of testosterone serum levels in testicular interstitial fluid under thyroxine influence

    International Nuclear Information System (INIS)

    Silva, Isvania Maria S. da; Pereira, Simey de L.S.; Souza, Grace Mary L.; Carvalho, Elaine F.M.B.; Catanho, Maria Teresa J. de A.; Silveira, Maria de Fatima G. da; Lima Filho, Guilherme L.

    2000-01-01

    The thyroid hormones possibly exert a reciprocal action between testicular steroids and Sertoli's cells during the premature period. This work aims to evaluate thyroxine effect on testosterone serum levels and in the testicular interstitial fluid (TIF) in rats. Wistar males rats, 22 days old, 80g of body weight, were induced to hyperthyroidism with thyroxine (20μg/kg) in periods of 5, 10, 15 and 20 consecutive days. After the treatment the animals were weighed and sacrificed for blood and testis collection. From the blood serum and from the TIF drained from the testis were performed testes in order to obtain testosterone attached to 125 I with a specific activity of 36,86 MBq/ig. The results have shown a testosterone significant lineal increase in both - serum and TIF - in the group treated with thyroxine as a time function. In the control group, testosterone levels remained low in both serum and TIF dosages. As a result, we were able to verify that the testosterone levels could be modified by thyroxine in serum and TIF. And so, it could affect luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in hypophysis. (author)

  17. Impact of adjusting for the reciprocal relationship between maternal weight and free thyroxine during early pregnancy.

    LENUS (Irish Health Repository)

    Haddow, James E

    2013-02-01

    Among euthyroid pregnant women in a large clinical trial, free thyroxine (FT4) measurements below the 2.5th centile were associated with a 17 lb higher weight (2.9 kg\\/m(2)) than in the overall study population. We explore this relationship further.

  18. Early thyroxine treatment in Down syndrome and thyroid function later in life

    NARCIS (Netherlands)

    Zwaveling-Soonawala, Nitash; Witteveen, M. Emma; Marchal, Jan Pieter; Klouwer, Femke C. C.; Ikelaar, Nadine A.; Smets, Anne M. J. B.; van Rijn, Rick R.; Endert, Erik; Fliers, Eric; van Trotsenburg, A. S. Paul

    2017-01-01

    Objective: The hypothalamus-pituitary-thyroid (HPT) axis set point develops during the fetal period and first two years of life. We hypothesized that thyroxine treatment during these first two years, in the context of a randomized controlled trial (RCT) in children with Down syndrome, may have

  19. False radioimmunoassay of thyroxine and triiodothyronine in the presence of hormone binding autoantibodies in serum

    International Nuclear Information System (INIS)

    Herrmann, J.; Kley, H.K.; Rudorff, K.H.; Kroell, H.J.; Krueskemper, H.L.

    1976-01-01

    Radioimmuno-assay of thyroxine and triiodothyronine in a 14-year-old girl with primary hypothyroidism and nodular goitre as a result of Hashimoto's thyroiditis gave falsely low values due to the presence of hormone-binding antibodies. Such antibodies occur in Hashimoto's thyroiditis and thyroid carcinoma. Their presence requires special methods for determining these hormones. (orig.) [de

  20. Focused genetic recombination of bacteriophage t4 initiated by double-strand breaks.

    Science.gov (United States)

    Shcherbakov, Victor; Granovsky, Igor; Plugina, Lidiya; Shcherbakova, Tamara; Sizova, Svetlana; Pyatkov, Konstantin; Shlyapnikov, Michael; Shubina, Olga

    2002-10-01

    A model system for studying double-strand-break (DSB)-induced genetic recombination in vivo based on the ets1 segCDelta strain of bacteriophage T4 was developed. The ets1, a 66-bp DNA fragment of phage T2L containing the cleavage site for the T4 SegC site-specific endonuclease, was inserted into the proximal part of the T4 rIIB gene. Under segC(+) conditions, the ets1 behaves as a recombination hotspot. Crosses of the ets1 against rII markers located to the left and to the right of ets1 gave similar results, thus demonstrating the equal and symmetrical initiation of recombination by either part of the broken chromosome. Frequency/distance relationships were studied in a series of two- and three-factor crosses with other rIIB and rIIA mutants (all segC(+)) separated from ets1 by 12-2100 bp. The observed relationships were readily interpretable in terms of the modified splice/patch coupling model. The advantages of this localized or focused recombination over that distributed along the chromosome, as a model for studying the recombination-replication pathway in T4 in vivo, are discussed.

  1. Structural studies on metal-containing enzymes: T4 endonuclease VII and D. gigas formate dehydrogenase

    NARCIS (Netherlands)

    Raaijmakers, H.C.A.

    2001-01-01

    Many biological processes require metal ions, and many of these metal-ion functions involve metalloproteins. The metal ions in metalloproteins are often critical to the protein's function, structure, or stability. This thesis focuses on two of these proteins, bacteriophage T4 endonuclease

  2. Modelling T4 cell count as a marker of HIV progression in the ...

    African Journals Online (AJOL)

    ∗Corresponding author: Department of Industrial and Systems Engineering, University ... T4 cell count as a marker of HIV progression in the absence of any defense ... This observation enables us to make the assumption that the population of ...

  3. The isolation and characterization of Stenotrophomonas maltophilia T4-like bacteriophage DLP6.

    Directory of Open Access Journals (Sweden)

    Danielle L Peters

    Full Text Available Increasing isolation of the extremely antibiotic resistant bacterium Stenotrophomonas maltophilia has caused alarm worldwide due to the limited treatment options available. A potential treatment option for fighting this bacterium is 'phage therapy', the clinical application of bacteriophages to selectively kill bacteria. Bacteriophage DLP6 (vB_SmoM-DLP6 was isolated from a soil sample using clinical isolate S. maltophilia strain D1571 as host. Host range analysis of phage DLP6 against 27 clinical S. maltophilia isolates shows successful infection and lysis in 13 of the 27 isolates tested. Transmission electron microscopy of DLP6 indicates that it is a member of the Myoviridae family. Complete genome sequencing and analysis of DLP6 reveals its richly recombined evolutionary history, featuring a core of both T4-like and cyanophage genes, which suggests that it is a member of the T4-superfamily. Unlike other T4-superfamily phages however, DLP6 features a transposase and ends with 229 bp direct terminal repeats. The isolation of this bacteriophage is an exciting discovery due to the divergent nature of DLP6 in relation to the T4-superfamily of phages.

  4. Modular architecture of the T4 phage superfamily: A conserved core genome and a plastic periphery

    International Nuclear Information System (INIS)

    Comeau, Andre M.; Bertrand, Claire; Letarov, Andrei; Tetart, Francoise; Krisch, H.M.

    2007-01-01

    Among the most numerous objects in the biosphere, phages show enormous diversity in morphology and genetic content. We have sequenced 7 T4-like phages and compared their genome architecture. All seven phages share a core genome with T4 that is interrupted by several hyperplastic regions (HPRs) where most of their divergence occurs. The core primarily includes homologues of essential T4 genes, such as the virion structure and DNA replication genes. In contrast, the HPRs contain mostly novel genes of unknown function and origin. A few of the HPR genes that can be assigned putative functions, such as a series of novel Internal Proteins, are implicated in phage adaptation to the host. Thus, the T4-like genome appears to be partitioned into discrete segments that fulfil different functions and behave differently in evolution. Such partitioning may be critical for these large and complex phages to maintain their flexibility, while simultaneously allowing them to conserve their highly successful virion design and mode of replication

  5. [Combined l-thyroxine and l-triiodothyronine replacement therapy in congenital hypothyroidism].

    Science.gov (United States)

    Péter, Ferenc; Muzsnai, Agota

    2013-05-12

    L-thyroxine replacement therapy is the treatment of choice for hypothyroidism. Recently, several studies suggested to complete it with l-triiodothyronine in acquired hypothyroidism. To study the role of combined l-thyroxine and l-triiodothyronine therapy in special cases with congenital hypothyroidism. Data of 16 patients (age: 11.9 ± 6.3 years; mean ± SD) are presented who had high serum free thyroxine values or even above the upper limit of reference range (21.16 ± 2.5 pmol/l) together with nonsuppressed TSH levels (15.7 ± 5.7 mIU/l), and therefore received l-triiodothyronine in completion (0.18 ± 0.09 μg/kg) once a day. The combined replacement therapy resulted in a rapid improvement of the hormone parameters (TSH: 4.2 ± 3.15 mIU/l; free thyroxine: 16.55 ± 2.4 and free triiodothyronine: 7.4 ± 1.8 pmol/l). The efficiency of this combined therapy proved to be more evident (TSH: 4.33 ± 3.2 mIU/l; free thyroxine: 16.85 ± 3.1 and free triiodothyronine: 6.4 ± 0.85 pmol/l) in 10 patients treated for a longer period of time (duration of treatment: 2.9 ± 2.0 years). The dose of thyroxine substitution decreased from 2.6 ± 0.9 to 2.18 ± 0.6 μg/kg/day), the ratio of these hormones was between 5:1 and 19:1 and the quotient of free fractions was normalized (3.8 ± 0.4→2.6 ± 0.3) during the replacement therapy. According to the observation of the authors a serious disturbance of feed-back mechanism may develop in some (>5%) children with congenital hypothyroidism (increased TSH release despite elevated free thyroxine level) after normal function of the feed-back system for years. Hormone parameters of these patients improve, then become normal on combined therapy supporting the rationale for this treatment method.

  6. Differential effect of L3T4+ cells on recovery from total-body irradiation

    International Nuclear Information System (INIS)

    Pantel, K.; Nakeff, A.

    1990-01-01

    We have examined the importance of L3T4+ (murine equivalent to CD4+) cells for hematopoietic regulation in vivo in unperturbed mice and mice recovering from total-body irradiation (TBI) using a cytotoxic monoclonal antibody (MoAb) raised with the GK 1.5 hybridoma. Ablating L3T4+ cells in normal (unperturbed) B6D2F1 mice substantially decreased the S-phase fraction (determined by in vivo hydroxyurea suicide) of erythroid progenitor cells (erythroid colony-forming units, CFU-E) as compared to the pretreatment level (10% +/- 14.1% [day 3 following depletion] vs 79.8% +/- 15.9%, respectively) with a corresponding decrease in the marrow content of CFU-E at this time to approximately 1% of the pretreatment value. Although the S-phase fraction of CFU-GM was decreased to 2.2% +/- 3.1% 3 days after L3T4+ cell ablation from the 21.3% +/- 8.3% pretreatment value, CFU-GM cellularity showed little change over the 3 days following anti-L3T4 treatment. Anti-L3T4 MoAb treatment had little or no effect on either the S-phase fraction or the marrow content of hematopoietic stem cells (spleen colony-forming units, CFU-S) committed to myeloerythroid differentiation. Ablating L3T4+ cells prior to a single dose of 2 Gy TBI resulted in significantly reduced marrow contents of CFU-S on day 3 and granulocyte-macrophage colony-forming units (CFU-GM) on day 6 following TBI, with little or no effect on the corresponding recovery of CFU-E. The present findings provide the first in vivo evidence that L3T4+ cells are involved in: (1) maintaining the proliferative activity of CFU-E and CFU-GM in unperturbed mice and (2) supporting the restoration of CFU-S and CFU-GM following TBI-induced myelosuppression

  7. Role of L-thyroxin in counteracting rotenone induced neurotoxicity in rats.

    Science.gov (United States)

    Salama, Mohamed; Helmy, Basem; El-Gamal, Mohamed; Reda, Amr; Ellaithy, Amr; Tantawy, Dina; Mohamed, Mie; El-Gamal, Aya; Sheashaa, Hussein; Sobh, Mohamed

    2013-03-01

    A key feature of Parkinson's disease is the dopaminergic neuronal cell loss in the substantia nigra pars compacta. Many triggering pathways have been incriminated in the pathogenesis of this disease including inflammation, oxidative stress, excitotoxicity and apoptosis. Thyroid hormone is an essential agent for the growth and maturation of neurons; moreover, it has variable mechanisms for neuroprotection. So, we tested the efficacy of (L)-thyroxin as a neuroprotectant in rotenone model of Parkinson's disease in rats. Thirty Sprague Dawley rats aged 3 months were divided into 3 equal groups. The first received daily intraperitoneal injections of 0.5% carboxymethyl cellulose (CMC) 3 mL/Kg. The second group received rotenone suspended in 0.5% CMC intraperitoneally at a dose of 3 mg/kg, daily. The third group received the same rotenone regimen subcutaneous l-thyroxine at a dose of 7.5 μg daily. All animals were evaluated regarding locomotor disturbance through blinded investigator who monitored akinesia, catalepsy, tremors and performance in open field test. After 35 days the animals were sacrificed and their brains were immunostained against anti-tyrosine hydroxylase and iba-1. Photomicrographs for coronal sections of the substantia nigra and striatum were taken and analyzed using image J software to evaluate cell count in SNpc and striatal fibers density and number of microglia in the nigrostriatal system. The results were then analyzed statistically. Results showed selective protective effects of thyroxin against rotenone induced neurotoxicity in striatum, however, failed to exert similar protection on SN. Moreover, microglial elevated number in nigrostriatal system that was induced by rotenone injections was diminished selectively in striatum only in the l-thyroxin treated group. One of the possible mechanisms deduced from this work was the selective regulation of microglia in striatal tissues. Thus, this study provides an insight into thyroxin neuroprotection

  8. Prognostic Value of Subclassification Using MRI in the T4 Classification Nasopharyngeal Carcinoma Intensity-Modulated Radiotherapy Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chen Lei [State Key Laboratory of Oncology in South China, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou (China); Liu Lizhi [State Key Laboratory of Oncology in South China, Imaging Diagnosis and Interventional Center, Sun Yat-sen University Cancer Center, Guangzhou (China); Chen Mo; Li Wenfei; Yin Wenjing [State Key Laboratory of Oncology in South China, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou (China); Lin Aihua [Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou (China); Sun Ying [State Key Laboratory of Oncology in South China, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou (China); Li Li [State Key Laboratory of Oncology in South China, Imaging Diagnosis and Interventional Center, Sun Yat-sen University Cancer Center, Guangzhou (China); Ma Jun, E-mail: majun2@mail.sysu.edu.cn [State Key Laboratory of Oncology in South China, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou (China)

    2012-09-01

    Purpose: To subclassify patients with the T4 classification nasopharyngeal carcinoma (NPC), according to the seventh edition of the American Joint Committee on Cancer staging system, using magnetic resonance imaging (MRI), and to evaluate the prognostic value of subclassification after intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 140 patients who underwent MRI and were subsequently histologically diagnosed with nondisseminated classification T4 NPC received IMRT as their primary treatment and were included in this retrospective study. T4 patients were subclassified into two grades: T4a was defined as a primary nasopharyngeal tumor with involvement of the masticator space only; and T4b was defined as involvement of the intracranial region, cranial nerves, and/or orbit. Results: The 5-year overall survival (OS) rate and distant metastasis-free survival (DMFS) rate for T4a patients (82.5% and 87.0%, respectively), were significantly higher than for T4b patients (62.6% and 66.8%; p = 0.033 and p = 0.036, respectively). The T4a/b subclassification was an independent prognostic factor for OS (hazard ratio = 2.331, p = 0.032) and DMFS (hazard ratio = 2.602, p = 0.034), and had no significant effect on local relapse-free survival. Conclusions: Subclassification of T4 patients, as T4a or T4b, using MRI according to the site of invasion, has prognostic value for the outcomes of IMRT treatment in NPC.

  9. Hepatic sinusoid is not well-stirred: estimation of the degree of axial mixing by analysis of lobular concentration gradients formed during uptake of thyroxine by the perfused rat liver

    International Nuclear Information System (INIS)

    Weisiger, R.A.; Mendel, C.M.; Cavalieri, R.R.

    1986-01-01

    Two general models have been proposed for predicting the effects of metabolism, protein binding, and plasma flow on the removal of drugs by the liver. These models differ in the degree of plasma mixing assumed to exist within each hepatic sinusoid. The venous equilibrium model treats the sinusoid as a single well-stirred compartment, whereas the sinusoidal model effectively breaks up the sinusoid into a large number of sequentially perfused compartments which do not exchange their contents except through plasma flow. As a consequence, the sinusoidal model, but not the venous equilibrium model, predicts that the concentration of highly extracted drugs will decline as the plasma flows through the hepatic lobule. To determine which of these alternative models best describes the hepatic uptake process, we looked for evidence that concentration gradients are formed during the uptake of [ 125 I]thyroxine by the perfused rat liver. Autoradiography of tissue slices after perfusion of the portal vein at physiologic flow rates with protein-free buffer containing [ 125 I]thyroxine demonstrated a rapid exponential fall in grain density with distance from the portal venule, declining by half for each 8% of the mean length of the sinusoid. Reversing the direction of perfusate flow reversed the direction of the autoradiographic gradients, indicating that they primarily reflect differences in the concentration of thyroxine within the hepatic sinusoids rather than differences in the uptake capacity of portal and central hepatocytes. Analysis of the data using models in which each sinusoid was represented by different numbers of sequentially perfused compartments (1-20) indicated that at least eight compartments were necessary to account for the magnitude of the gradients seen

  10. The administration of L-thyroxine as soft gel capsule or liquid solution.

    Science.gov (United States)

    Vita, Roberto; Fallahi, Poupak; Antonelli, Alessandro; Benvenga, Salvatore

    2014-07-01

    Levothyroxine (l-T4) is the mainstay of treating hypothyroidism. The tablet is the traditional formulation of l-T4. Tablet l-T4 malabsorption results from either hindered gastric dissolution of the tablet or binding of l-T4 by sequestrants in the intestinal lumen. This review provides an overview of the pharmacokinetics of l-T4 formulations available in the market: the tablet, the soft gel capsule and the oral solution. We review literature on the new formulations and anticipate the areas of future research. Failure of l-T4 treatment to reach target serum thyroid-stimulating hormone levels generally prompts the physicians to increase l-T4 daily dose. In vitro studies have shown that the soft gel capsule releases the active ingredient more consistently at varying pH than the tablet. In addition, in vivo studies have confirmed the in vitro data and have demonstrated that both the soft gel capsule and the liquid formulation are capable to solve tablet l-T4 malabsorption caused by certain drugs, bariatric surgery or coffee. These new formulations may be attractive also for patients who cannot/do not want to change their (improper) habits of l-T4 ingestion. Finally, the oral solution l-T4 could be suitable for patients who cannot swallow the solid formulations.

  11. Thyroid hormones and deiodinase activity in plasma and tissues in relation to high levels of organohalogen contaminants in East Greenland polar bears (Ursus maritimus).

    Science.gov (United States)

    Gabrielsen, Kristin Møller; Krokstad, Julie Stene; Villanger, Gro Dehli; Blair, David A D; Obregon, Maria-Jesus; Sonne, Christian; Dietz, Rune; Letcher, Robert J; Jenssen, Bjørn Munro

    2015-01-01

    Previous studies have shown relationships between organohalogen contaminants (OHCs) and circulating levels of thyroid hormones (THs) in arctic wildlife. However, there is a lack of knowledge concerning the possible functional effects of OHCs on TH status in target tissues for TH-dependent activity. The relationships between circulating (plasma) levels of OHCs and various TH variables in plasma as well as in liver, muscle and kidney tissues from East Greenland sub-adult polar bears (Ursus maritimus) sampled in 2011 (n=7) were therefore investigated. The TH variables included 3.3',5.5'-tetraiodothyronine or thyroxine (T4), 3.3',5-triiodothyronine (T3) and type 1 (D1) and type 2 (D2) deiodinase activities. Principal component analysis (PCA) combined with correlation analyses demonstrated negative relationships between individual polychlorinated biphenyls (PCBs) and their hydroxylated (OH-) metabolites and T4 in both plasma and muscle. There were both positive and negative relationships between individual OHCs and D1 and D2 activities in muscle, liver and kidney tissues. In general, PCBs, OH-PCBs and polybrominated dipehenyl ethers (PBDEs) were positively correlated to D1 and D2 activities, whereas organochlorine pesticides and byproducts (OCPs) were negatively associated with D1 and D2 activities. These results support the hypothesis that OHCs can affect TH status and action in the target tissues of polar bears. TH levels and deiodinase activities in target tissues can be sensitive endpoints for exposure of TH-disrupting compounds in arctic wildlife, and thus, tissue-specific responses in target organs should be further considered when assessing TH disruption in wildlife studies. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Comparative studies of commercially available T4-RIA-kits. Pt. 2

    International Nuclear Information System (INIS)

    Schmidt, H.A.E.; Lipke, P.

    1978-01-01

    The investigation of the tested commercially available T 4 -RIA-Kits have shown that: The separation of hypo-, eu- and hyperthyroid values is better with kits a) and f) than with b), c), d) and e), though all kits give acceptable values under routine operating conditions, kit b) takes less time and work than the other tested kits, depending on the kit used, the time needed for 100 determinations varies between 1,5 and 4 hr. A general recommendation for one of the tested T 4 -RIA-Kits cannot be made since the choice of a kit depends not only on the criteria discussed but also on local circumstances. (orig.) [de

  13. Repair of potentially lethal damage by introduction of T4 DNA ligase in eucaryotic cells

    International Nuclear Information System (INIS)

    Durante, M.; Grossi, G.F.; Napolitano, M.; Gialanella, G.

    1991-01-01

    The bacterial enzyme PvuII, which generates blunt-ended DNA double-strand breaks, and T4 DNA ligase, which seals adjacent DNA fragments in coupling to ATP cleavage, were introduced in mouse C3H10T1/2 fibroblasts using osmolytic shock of pinocytic vesicles. Cells were then assayed for their clonogenic ability. In agreement with previous studies by others, the authors found that PvuII restriction endonuclease simulates ionizing radiation effects by causing a dose-dependent loss of reproductive capacity. They show that concomitant treatment with DNA ligase considerably increases cell survival. Survival curves were shown to be dependent on ligase enzyme dose and on ATP concentration in the hypertonic medium. They conclude that T4 DNA ligase is able to repair some potentially lethal damage produced by restriction endonucleases in eucaryotic cells. (author)

  14. Characterization of a bacteriophage T4 mutant lacking DNA-dependent ATPase

    International Nuclear Information System (INIS)

    Behme, M.T.; Ebisuzaki, K.

    1975-01-01

    A DNA-dependent ATPase has previously been purified from bacteriophage T4-infected Escherichia coli. A mutant phage strain lacking this enzyme has been isolated and characterized. Although the mutant strain produced no detectable DNA-dependent ATPase, growth properties were not affected. Burst sizes were similar for the mutant phage and T4D in polAl, recB, recC, uvrA, uvrB, uvrC, and various DNA-negative E. coli. UV sensitivity and genetic recombination were normal in a variety of E. coli hosts. Mapping data indicate that the genetic locus controlling the mutant occurs near gene 56. The nonessential nature of this gene is discussed

  15. Radiation-induced osteochondroma of the T4 vertebra causing spinal cord compression

    Energy Technology Data Exchange (ETDEWEB)

    Gorospe, Luis; Madrid-Muniz, Carmen; Royo, Aranzazu; Garcia-Raya, Pilar [Department of Radiology, La Paz University Hospital, Madrid (Spain); Alvarez-Ruiz, Fernando [Department of Neurosurgery, La Paz University Hospital, Madrid (Spain); Lopez-Barea, Fernando [Department of Pathology, La Paz University Hospital, Madrid (Spain)

    2002-04-01

    A case of a radiation-induced osteochondroma arising from the vertebral body of T4 in an 18-year-old man is reported. The patient presented with a history of progressive left lower extremity weakness. At 7 years of age, he had undergone resection of a cerebellar medulloblastoma and received adjunctive craniospinal irradiation and systemic chemotherapy. Both CT and MR imaging revealed an extradural mass contiguous with the posteroinferior endplate of the T4 vertebral body. This case indicates that radiation-induced osteochondroma should be considered in the differential diagnosis of patients with symptoms of myelopathy or nerve root compression and a history of radiation therapy involving the spine in childhood. (orig.)

  16. Early thyroxine treatment in Down syndrome and thyroid function later in life.

    Science.gov (United States)

    Zwaveling-Soonawala, Nitash; Witteveen, M Emma; Marchal, Jan Pieter; Klouwer, Femke C C; Ikelaar, Nadine A; Smets, Anne M J B; van Rijn, Rick R; Endert, Erik; Fliers, Eric; van Trotsenburg, A S Paul

    2017-05-01

    The hypothalamus-pituitary-thyroid (HPT) axis set point develops during the fetal period and first two years of life. We hypothesized that thyroxine treatment during these first two years, in the context of a randomized controlled trial (RCT) in children with Down syndrome, may have influenced the HPT axis set point and may also have influenced the development of Down syndrome-associated autoimmune thyroiditis. We included 123 children with Down syndrome 8.7 years after the end of an RCT comparing thyroxine treatment vs placebo and performed thyroid function tests and thyroid ultrasound. We analyzed TSH and FT4 concentrations in the subgroup of 71 children who were currently not on thyroid medication and had no evidence of autoimmune thyroiditis. TSH concentrations did not differ, but FT4 was significantly higher in the thyroxine-treated group than that in the placebo group (14.1 vs 13.0 pmol/L; P  = 0.02). There was an increase in anti-TPO positivity, from 1% at age 12 months to 6% at age 24 months and 25% at age 10.7 years with a greater percentage of children with anti-TPO positivity in the placebo group (32%) compared with the thyroxine-treated group (18.5%) ( P  = 0.12). Thyroid volume at age 10.7 years (mean: 3.4 mL; range: 0.5-7.5 mL) was significantly lower ( P  treatment during the first two years of life led to a mild increase in FT4 almost 9 years later on and may point to an interesting new mechanism influencing the maturing HPT axis set point. Furthermore, there was a trend toward less development of thyroid autoimmunity in the thyroxine treatment group, suggesting a protective effect of the early thyroxine treatment. Lastly, thyroid volume was low possibly reflecting Down-specific thyroid hypoplasia. © 2017 European Society of Endocrinology.

  17. Pulsating strings from two-dimensional CFT on (T4N/S(N

    Directory of Open Access Journals (Sweden)

    Carlos Cardona

    2015-04-01

    Full Text Available We propose a state from the two-dimensional conformal field theory on the orbifold (T4N/S(N as a dual description for a pulsating string moving in AdS3. We show that, up to first order in the deforming parameter, the energy in both descriptions has the same dependence on the mode number, but with a non-trivial function of the coupling.

  18. Differential cross section measurement for the 6Li(n,t)4He Reaction

    International Nuclear Information System (INIS)

    Zhang Guohui; Tang Guoyou; Chen Jinxiang; Shi Zhaomin

    2002-01-01

    The differential cross sections and integrated cross sections of the 6 Li(n,t) 4 He reaction were measured at 1.85 and 2.67 MeV by using a gridded ionization chamber. Neutrons were produced through the T(p, n) 3 He reaction. The absolute neutron flux was determined through the 238 U(n, f) reaction. Present results are compared with existing data

  19. Three magnetic particles solid phase radioimmunoassay for T4: Comparison of their results with established methods

    International Nuclear Information System (INIS)

    Bashir, T.

    1996-01-01

    The introduction of solid phase separation techniques is an important improvement in radioimmunoassays and immunoradiometric assays. Magnetic particle solid phase method has additional advantages over others, as the separation is rapid and centrifugation is not required. Three types of magnetic particles have been studied in T 4 RIA and the results have been compared with commercial kits and other established methods. (author). 4 refs, 9 figs, 2 tabs

  20. Molecular dynamics simulations of deoxyribonucleic acids and repair enzyme T4 endonuclease V

    International Nuclear Information System (INIS)

    Pinak, Miroslav

    1999-01-01

    This report describes the results of molecular dynamics (MD) simulation of deoxyribonucleic acids (DNA) and specific repair enzyme T4 endonuclease V. Namely research described here is focused on the examination of specific recognition process, in which this repair enzyme recognizes the damaged site on the DNA molecule-thymine dimer (TD). TD is frequent DNA damage induced by UV radiation in sun light and unless properly repaired it may be mutagenic or lethal for cell, and is also considered among the major causes of skin cancer. T4 endonuclease V is a DNA specific repair enzyme from bacteriophage T4 that catalyzes the first reaction step of TD repair pathway. MD simulations of three molecules - native DNA dodecamer (12 base pairs), DNA of the same sequence of nucleotides as native one but with TD, and repair enzyme T4 endonuclease V - were performed for 1 ns individually for each molecule. Simulations were analyzed to determine the role of electrostatic interaction in the recognition process. It is found that electrostatic energies calculated for amino acids of the enzyme have positive values of around +15 kcal/mol. The electrostatic energy of TD site has negative value of approximately -9 kcal/mol, different from the nearly neutral value of the respective thymines site of the native DNA. The electrostatic interaction of TD site with surrounding water environment differs from the electrostatic interaction of other nucleotides. Differences found between TD site and respective thymines site of native DNA indicate that the electrostatic energy is an important factor contributing to proper recognition of TD site during scanning process in which enzyme scans the DNA. In addition to the electrostatic energy, the important factor in recognition process might be structural complementarity of enzyme and bent DNA with TD. There is significant kink formed around TD site, that is not observed in native DNA. (author)

  1. T4 category revision enhances the accuracy and significance of stage III breast cancer.

    Science.gov (United States)

    Güth, Uwe; Singer, Gad; Langer, Igor; Schötzau, Andreas; Herberich, Linda; Holzgreve, Wolfgang; Wight, Edward

    2006-06-15

    Because of the considerable heterogeneity in breast carcinoma with noninflammatory skin involvement (T4b/Stage IIIB), a revision was proposed of the TNM staging system that would classify these tumors exclusively based on their tumor size and lymph node status. In the current study, the authors evaluated how implementation of this proposal will affect Stage III noninflammatory breast cancer. Two hundred seven patients who were classified with noninflammatory Stage III breast cancer were treated consecutively between 1990 and 1999 at the University Hospital Basel, Switzerland. To assess the extent of T4b/Stage IIIB tumors independent of the clinicopathologic feature of skin involvement, the reclassification was undertaken. Of 68 patients who had nonmetastatic T4b breast cancer, 37 patients (54.4%) had a tumor extent in accordance with Stage I/II and had improved disease-specific survival (DSS) compared with patients who had Stage III breast cancer (P = .008). Excluding those patients from Stage III led to a 17.9% reduction of the number of patients in this group (n = 170 patients). The 10-year DSS declined from 48.5% to 42.9%. Considerable numbers of patients who are classified with noninflammatory Stage IIIB breast cancer show only a limited disease extent. Through a revision of the T4 category, these low-risk patients were excluded from the highest nonmetastatic TNM stage, and overstaging could be avoided. This procedure decreased the degree of heterogeneity of the entire Stage III group and may result in a more precise assessment of this disease entity. Copyright 2006 American Cancer Society.

  2. Experimental electromagnetic effects on the model organism Escherichia coli and the bacteriophage T4

    Science.gov (United States)

    Lisiewski, Darlene Mildred

    This experimentally-based work was designed to answer the research question as to whether the phenomenon of nuclear magnetic resonance (NMR) can produce observable effects upon the bacterial virus activity of T4, with such activity demonstrated through the infection of its host bacterium Escherichia coli. The biological samples were placed for three hours within a coil antenna assembly propagating oscillating fields of radio frequency electromagnetic energy generated at the frequency of 5.6 MHz, and set at right angles within a magnetic field of 1450 gauss (recognizing such conditions are not set for the maximum effective resonance for hydrogen nuclei). The laboratory technique of plaque formation was the basis upon which the statistically tested data were compiled. Exposure of the bacterium alone exhibited an increase in viral activity over the control group (40--68% higher numbers of plaque formation), while exposure of T4 alone saw a decrease (approximately 23%) in infection rates. Depending on the protocol, placement of both T4 and E. coli into the coil assembly saw a decrease of either approximately 50% or 42% in infection rates. Future research must address identification of the effects being observed.

  3. Sequence organization and control of transcription in the bacteriophage T4 tRNA region.

    Science.gov (United States)

    Broida, J; Abelson, J

    1985-10-05

    Bacteriophage T4 contains genes for eight transfer RNAs and two stable RNAs of unknown function. These are found in two clusters at 70 X 10(3) base-pairs on the T4 genetic map. To understand the control of transcription in this region we have completed the sequencing of 5000 base-pairs in this region. The sequence contains a part of gene 3, gene 1, gene 57, internal protein I, the tRNA genes and five open reading frames which most likely code for heretofore unidentified proteins. We have used subclones of the region to investigate the kinetics of transcription in vivo. The results show that transcription in this region consists of overlapping early, middle and late transcripts. Transcription is directed from two early promoters, one or two middle promoters and perhaps two late promoters. This region contains all of the features that are seen in T4 transcription and as such is a good place to study the phenomenon in more detail.

  4. Palliative telecobalt-60 with concentrated dose in TNM classification T4 of the breast

    International Nuclear Information System (INIS)

    Patricio, M.B.; Brites, C.F.; Guimaraes, M.F.; De Jesus, E.B.; Catita, J.I.; Vilhena, M.

    1986-01-01

    A method is presented of rapid, palliative radiotherapy for carcinoma of the breast, composed of two sessions of 6.5 or 8.5 Gy delivered at a 48-hour interval. The radiobiological equivalence of this unconventional technique is presented. Our preliminary results in a series of 80 patients were published in 1978. The present report is based on the analysis of 112 patients with T4 of the breast submitted to the flash dose, from March 1978 to December 1981. The method was used not only for relief of symptoms such as pain and hemorrhage, but also as part of intensive radiotherapy in all patients with good response and with no manifestation of distant dissemination so that they were able to resume treatment 2.5 or 3 weeks later, with conventional fractionation. Some of these patients became operable. About half of the cases had castration and/or hormone therapy and/or chemotherapy. In the group of patients with T4M0, 59.8% were alive after more than 1 year, and of them, 43.7% had no evidence of disease. These encouraging results suggest that this method be advocated in T4 of the breast because of its rapidity and good tolerance with no significant complications

  5. Processive nicking activity of T4 endonuclease V on UV-irradiated chromatin

    International Nuclear Information System (INIS)

    Gruskin, E.A.; Lloyd, R.S.

    1986-01-01

    T4 endonuclease V initiates the excision repair of pyrimidine dimers in UV-irradiated T4 infected E. coli cells. The pyrimidine dimer specific nicking activity of T4 endonuclease V functions by a processive scanning on UV-irradiated DNA. Previously it has been demonstrated that introduction of endonuclease V into repair-deficient human cells causes a restoration of UV survival in these cells. This demonstrates that endonuclease V is competent to incise mammalian DNA at the site of pyrimidine dimers. In order to assess the ability of endonuclease V to act processively on DNA associated as chromatin, minichromosomes were prepared for use as a substrate. Form I DNA was reconstituted with H3, H4 +/- H1 histones by sequential dialysis steps from 2.0 M NaCl to 50 mM NaCl. Time course reactions were performed with minichromosomes containing 10 and 25 dimers per molecule. In each case the rate of disappearance of form I DNA which was associated as chromatin was decreased relative to that of naked form I DNA. Concurrent with that observation, the rate and extent of appearance of form III DNA was increased with the DNA in minichromosomes relative to naked DNA. This is diagnostic of an enhancement of processivity. The inclusion of H1 in the minichromosomes resulted in a slight additional increase in processivity relative to minichromosomes consisting only of H3 and H4

  6. Synthesis and magnetic property of T4 virus-supported gold-coated iron ternary nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Xu Ziming; Sun Hongjing; Gao Faming, E-mail: fmgao@ysu.edu.cn; Hou Li; Li Na [Yanshan University, Key Laboratory of Applied Chemistry (China)

    2012-12-15

    Herein, we present a novel method based on the use of the symmetrical T4 bacteriophage capsid as a scaffold for preparing the gold-coated iron ternary core/shell nanostructure. Results showed that the thick gold shell was obtained to effectively protect Fe core from oxidation. Magnetic measurements showed that the nanocomposites were superparamagnetic at room temperature with a blocking temperature of about 35 K. At 3 K, its coercivity of 1142.86 Oe was larger than the existing experimental values. The magnetic property of Au/T4 was also tested, demonstrating the source of the magnetic sample arising from the Fe core only. The absorption spectrum of the Fe-Au/T4 complex was measured and compared with gold/virus. Different thickness gold shells were controlled in the synthesis by tuning the Au salt addition. On the basis of results and discussion, we further speculated the general growing mechanism of the template-supported Fe-Au process.

  7. Synthesis and magnetic property of T4 virus-supported gold-coated iron ternary nanocomposite

    Science.gov (United States)

    Xu, Ziming; Sun, Hongjing; Gao, Faming; Hou, Li; Li, Na

    2012-12-01

    Herein, we present a novel method based on the use of the symmetrical T4 bacteriophage capsid as a scaffold for preparing the gold-coated iron ternary core/shell nanostructure. Results showed that the thick gold shell was obtained to effectively protect Fe core from oxidation. Magnetic measurements showed that the nanocomposites were superparamagnetic at room temperature with a blocking temperature of about 35 K. At 3 K, its coercivity of 1142.86 Oe was larger than the existing experimental values. The magnetic property of Au/T4 was also tested, demonstrating the source of the magnetic sample arising from the Fe core only. The absorption spectrum of the Fe@Au/T4 complex was measured and compared with gold/virus. Different thickness gold shells were controlled in the synthesis by tuning the Au salt addition. On the basis of results and discussion, we further speculated the general growing mechanism of the template-supported Fe@Au process.

  8. Tensile behavior of friction stir welded AA 6061-T4 aluminum alloy joints

    International Nuclear Information System (INIS)

    Heidarzadeh, A.; Khodaverdizadeh, H.; Mahmoudi, A.; Nazari, E.

    2012-01-01

    Highlights: ► Range of parameters for defect-free friction stir welded AA 6061-T4 was reached. ► A model was developed for predicting UTS and EL of friction stir welded AA 6061-T4. ► The maximum values of UTS and EL of joints were estimated by developed model. ► The optimum values of FSW process parameters were determined. -- Abstract: In this investigation response surface methodology based on a central composite rotatable design with three parameters, five levels and 20 runs, was used to develop a mathematical model predicting the tensile properties of friction stir welded AA 6061-T4 aluminum alloy joints at 95% confidence level. The three welding parameters considered were tool rotational speed, welding speed and axial force. Analysis of variance was applied to validate the predicted model. Microstructural characterization and fractography of joints were examined using optical and scanning electron microscopes. Also, the effects of the welding parameters on tensile properties of friction stir welded joints were analyzed in detail. The results showed that the optimum parameters to get a maximum of tensile strength were 920 rev/min, 78 mm/min and 7.2 kN, where the maximum of tensile elongation was obtained at 1300 rev/min, 60 mm/min and 8 kN.

  9. Triiodothyronine and thyroxine in urine. II. Renal handling, and effect of urinary protein.

    Science.gov (United States)

    Burke, C W; Shakespear, R A

    1976-03-01

    Mean urinary clearances of T3 were 164 ml/min in normal subjects, 177 in pregnancy, 221 in thyrotoxicosis, 174 in hypothyroidism, and 194 in 3 persons with undetectable T4 but normal T3 levels. T4 clearances were 38 ml/min in normal subjects, 48 in thyrotoxicosis, and 138 in hypothyroidism. Low creatinine clearance was associated with low clearances of T4 and T3. The data suggest urinary excretion of T3 by glomerular filtration of serum unbound T3 with added tubular excretion; and T4 excretion by glomerular filtration of unbound T4 and tubular reabsorption. However, 3-9% of urinary T3 and 5-12% of urinary T4 were bound to urinary proteins, and increased protein excretion caused markedly increased T4 excretion. In addition, 52% of urinary T3 and 68% of urinary T4 were bound to other substances of approximate mol wt 500-2,000, which may influence tubular handling of T3 or T4.

  10. Conjugated effects of thyroxine and X-rays on the intestinal wall of Alytes obstetricans Larvae (Anuran Amphibian)

    International Nuclear Information System (INIS)

    Dauca, M.; Hourdry, J.

    1979-01-01

    The conjoined effects of thyroxine and X-rays on the intestinal wall were studied using Alytes obstetricans tadpoles in premetamorphosis. Thyroxine alone induced degeneration of the larval epithelium (primary epithelium) and its replacement by a secondary epithelium. The latter is derived from stem cells via the development of islets. In animals submitted to irradiation only, many of these stem cells showed signs of necrosis. In irradiated larvae treated with thyroxine, the secondary epitheliocytes were rare and never formed islets. Radioautographic observations confirmed their very low proliferation rate. Contrary to what was observed in the hormone treated larvae, cell fragments of the primary epithelium were extruded in the connective tissue, and phagocytes appear to infiltrate the epithelium. In animals treated with thyroxine and later submitted to irradiation, islets of secondary epitheliocytes developed while some cells degenerated. There again, the phagocytes were noted in both the connective tissue and the epithelium. (orig.) [de

  11. Radioimmunoassay methods for the determination of L-triiodo-thyronine and thyroxine

    International Nuclear Information System (INIS)

    1976-01-01

    An improved, simplified radioimmunoassay method for the in vitro determination of L-triiodo-thyronine in unextracted blood serum is described which involves the use of a combination reagent constituted by a buffered solution containing radioactive L-triiodothyronine and an inhibitor for inhibiting the binding of L-triiodothyronine to thyroxine-binding globulin. Optionally the reagent may also include an antiserum containing an antibody capable of immunoreactivity with L-triiodothyronine. Packaged test kits for use in conveniently carrying out the radioimmunoassay are also provided. Certain salts of 8-anilino-1-naphtalene sulfonic acid, which may be regarded as purified forms of the acid, are preferably employed as inhibitors for inhibiting binding of L-triiodothyronine to thyroxine-binding globulin

  12. Vibrational studies of Thyroxine hormone: Comparative study with quantum chemical calculations

    Science.gov (United States)

    Borah, Mukunda Madhab; Devi, Th. Gomti

    2017-11-01

    The FTIR and Raman techniques have been used to record spectra of Thyroxine. The stable geometrical parameters and vibrational wave numbers were calculated based on potential energy distribution (PED) using vibrational energy distribution analysis (VEDA) program. The vibrational energies are assigned to monomer, chain dimer and cyclic dimers of this molecule using the basis set B3LYP/LANL2DZ. The computational scaled frequencies are in good agreements with the experimental results. The study is extended to calculate the HOMO-LUMO energy gap, Molecular Electrostatic Potential (MEP) surface, hardness (η), chemical potential (μ), Global electrophilicity index (ω) and different thermo dynamical properties of Thyroxine in different states. The calculated HOMO-LUMO energies show the charge transfer occurs within the molecule. The calculated Natural bond orbital (NBO) analysis confirms the presence of intra-molecular charge transfer as well as the hydrogen bonding interaction.

  13. Thyroxine secretion rate during growth in different types of poultry birds

    International Nuclear Information System (INIS)

    Parshad, Omkar; Gupta, B.K.; Varman, P.N.

    1976-01-01

    Thyroid activity in pro- and post-pubertal as well as mature poultry birds of egg type i.e. White Leghorn (WLH); dual-purpose i.e. Rhode Island Red (RIR) and meat type i.e. Broiler strain was estimated by determining the thyroxine secretion rate (TSR) using 131 I as a radiotracer at 4 weeks, 14 weeks and 24 weeks of age. The study has revealed that the birds have higher thyroxine secretion rates during pre-pubertal as compared to the post-pubertal period as well as the period around the age of maturity. The birds of Broiler strain have higher TSR as compared to both the pure egg-type and the dual-purpose breeds. (author)

  14. Autoradiographic localization of 131I-labelled thyroxine in the tissues of rat

    International Nuclear Information System (INIS)

    Prakash, P.; Romack, F.E.

    1977-01-01

    An attempt was made to visualize the sites of localization of 131 I-labelled thyroxine in the tissues of the rat by autoradiographic dipping techniques. The maximal uptake of 131 I-thyroxine in rats occured at 12 hours in all the tissues examined. The radioactivity continued to decrease from 12 to 36 hours after the injection. In the liver and kidney, the decline after 12 hours was rather marked. The radioactivity decreased only slightly from 12 to 36 hours in the spleen. After 3 hours of injection, the radioactivity was consistently higher in the thyroid follicular epithelial cells than in the interfollicular connective tissue. A high concentration of radioactivity was found at the periphery of the colloid areas. (author)

  15. Thyrotoxic periodic paralysis due to excessive L-thyroxine replacement in a Caucasian man.

    LENUS (Irish Health Repository)

    Hannon, M J

    2009-09-01

    Thyrotoxic periodic paralysis is a potentially fatal complication of hyperthyroidism, more common in Asian races, which is defined by a massive intracellular flux of potassium. This leads to profound hypokalaemia and muscle paralysis. Although the paralysis is temporary, it may be lethal if not diagnosed and treated rapidly, as profound hypokalaemia may induce respiratory muscle paralysis or cardiac arrest. The condition is often misdiagnosed in the west due to its comparative rarity in Caucasians; however it is now increasingly described in Caucasians and is also being seen with increasing frequency in western hospitals due to increasing immigration and population mobility. Here we describe the case of a patient with panhypopituitarism due to a craniopharyngioma, who developed thyrotoxic periodic paralysis due to excessive L-thyroxine replacement. This disorder has been described in Asian subjects but, to our knowledge, thyrotoxic periodic paralysis secondary to excessive L-thyroxine replacement has never been described in Caucasians.

  16. Thermal stability of synthetic thyroid hormone l-thyroxine and l-thyroxine sodium salt hydrate both pure and in pharmaceutical formulations.

    Science.gov (United States)

    Ledeţi, Ionuţ; Ledeţi, Adriana; Vlase, Gabriela; Vlase, Titus; Matusz, Petru; Bercean, Vasile; Şuta, Lenuţa-Maria; Piciu, Doina

    2016-06-05

    In this paper, the thermal stability of pure l-thyroxine (THY) and l-thyroxine sodium salt hydrate (THYSS) vs. two pharmaceutical solid formulations commercialized on both Romanian and European market (with a content of 100μg, respectively 200μg THYSS per tablet) were investigated. In order to determine whether the presence of excipients affects the thermal stability of the active pharmaceutical ingredient (API), the preliminary study of thermal stability in air atmosphere was completed with an in-depth solid-state kinetic study. By kinetic analysis, the non-isothermal degradation of the selected active pharmaceutical ingredients vs. the solid formulation with strength of 200μg THYSS per tablet was investigated. Isoconversional methods (Kissinger-Akahira-Sunose, Flynn-Wall-Ozawa and Friedman) were employed for the estimation of activation energies values, at five different heating rates, β=5, 7, 10, 12 and 15°Cmin(-1). Also, a fourth method was applied in the processing of data, namely NPK, allowing an objective separation in the physical and chemical processes that contribute to the thermal degradation of the selected compounds. A discussion of thermal stability from the kinetic point of view is also presented. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Effects of In Utero Thyroxine Exposure on Murine Cranial Suture Growth.

    Directory of Open Access Journals (Sweden)

    R Nicole Howie

    Full Text Available Large scale surveillance studies, case studies, as well as cohort studies have identified the influence of thyroid hormones on calvarial growth and development. Surveillance data suggests maternal thyroid disorders (hyperthyroidism, hypothyroidism with pharmacological replacement, and Maternal Graves Disease are linked to as much as a 2.5 fold increased risk for craniosynostosis. Craniosynostosis is the premature fusion of one or more calvarial growth sites (sutures prior to the completion of brain expansion. Thyroid hormones maintain proper bone mineral densities by interacting with growth hormone and aiding in the regulation of insulin like growth factors (IGFs. Disruption of this hormonal control of bone physiology may lead to altered bone dynamics thereby increasing the risk for craniosynostosis. In order to elucidate the effect of exogenous thyroxine exposure on cranial suture growth and morphology, wild type C57BL6 mouse litters were exposed to thyroxine in utero (control = no treatment; low ~167 ng per day; high ~667 ng per day. Thyroxine exposed mice demonstrated craniofacial dysmorphology (brachycranic. High dose exposed mice showed diminished area of the coronal and widening of the sagittal sutures indicative of premature fusion and compensatory growth. Presence of thyroid receptors was confirmed for the murine cranial suture and markers of proliferation and osteogenesis were increased in sutures from exposed mice. Increased Htra1 and Igf1 gene expression were found in sutures from high dose exposed individuals. Pathways related to the HTRA1/IGF axis, specifically Akt and Wnt, demonstrated evidence of increased activity. Overall our data suggest that maternal exogenous thyroxine exposure can drive calvarial growth alterations and altered suture morphology.

  18. Effects of In Utero Thyroxine Exposure on Murine Cranial Suture Growth.

    Science.gov (United States)

    Howie, R Nicole; Durham, Emily L; Black, Laurel; Bennfors, Grace; Parsons, Trish E; Elsalanty, Mohammed E; Yu, Jack C; Weinberg, Seth M; Cray, James J

    2016-01-01

    Large scale surveillance studies, case studies, as well as cohort studies have identified the influence of thyroid hormones on calvarial growth and development. Surveillance data suggests maternal thyroid disorders (hyperthyroidism, hypothyroidism with pharmacological replacement, and Maternal Graves Disease) are linked to as much as a 2.5 fold increased risk for craniosynostosis. Craniosynostosis is the premature fusion of one or more calvarial growth sites (sutures) prior to the completion of brain expansion. Thyroid hormones maintain proper bone mineral densities by interacting with growth hormone and aiding in the regulation of insulin like growth factors (IGFs). Disruption of this hormonal control of bone physiology may lead to altered bone dynamics thereby increasing the risk for craniosynostosis. In order to elucidate the effect of exogenous thyroxine exposure on cranial suture growth and morphology, wild type C57BL6 mouse litters were exposed to thyroxine in utero (control = no treatment; low ~167 ng per day; high ~667 ng per day). Thyroxine exposed mice demonstrated craniofacial dysmorphology (brachycranic). High dose exposed mice showed diminished area of the coronal and widening of the sagittal sutures indicative of premature fusion and compensatory growth. Presence of thyroid receptors was confirmed for the murine cranial suture and markers of proliferation and osteogenesis were increased in sutures from exposed mice. Increased Htra1 and Igf1 gene expression were found in sutures from high dose exposed individuals. Pathways related to the HTRA1/IGF axis, specifically Akt and Wnt, demonstrated evidence of increased activity. Overall our data suggest that maternal exogenous thyroxine exposure can drive calvarial growth alterations and altered suture morphology.

  19. [Partial thyroxine binding globulin deficiency in test tube infants: report of cases and literature review].

    Science.gov (United States)

    Fang, Y L; Wang, C L; Liang, L

    2016-06-02

    To investigate the clinical characteristics of twins with thyroxine binding globulin (TBG) deficiency and to find SERPINA7 gene mutations. Data(2015) related to clinical characteristics, serum biochemistry, gene mutations and pedigree of two children with TBG deficiency were collected in the First Affiliated Hospital of College of Medicine, Zhejiang University. The related literature was searched form China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, National Center for Biotechnology Information and PubMed (up to December 2015) by using search terms "Thyroxine binding globulin deficiency, gene, mutation" . Both patients were diagnosed as central hypothyroidism at the beginning and treated with L-thyroxine. Both of the identical twins of the triplet were observed for mutation in exon3, c. 631G﹥A(p.A211T), a new mutation had not been reported, but their parents and another non-identical triplet brother were normal. Literature review showed that 23 foreign cases with SERPINA7 gene mutation had been reported, however, no Chinese with SERPINA7 gene mutation had been reported. Among reported cases it was shown that SERPINA7 gene mutations located in exon, intron, promoter and enhancer. Up to now, 49 variants had been identified, 41 of them located in the mutated genes. Including these two cases, patients with thyroxine binding globulin deficiency were characterized by reduced serum TH levels, but normal free TH and TSH and absence of clinical manifestations. The new mutation of SERPINA7 gene c. 631G﹥A(p.A211T)is not transmitted via the known X chromosome linked heredity, and as the cases were test tube triplet infants, it is a de novo mutation. The serum thyroid function tests of TBG deficiency showed decreased TT4, TT3 and normal TSH and TBG deficiency is often misdiagnosed as central hypothyroidism.

  20. Thyroxin and progesterone concentrations in pregnant, nonpregnant bitches, and bitches during abortion.

    Science.gov (United States)

    Thuróczy, Julianna; Müller, Linda; Kollár, Eszter; Balogh, Lajos

    2016-04-01

    Serum progesterone and thyroxin concentrations were measured weekly until 61 to 62 days after ovulation in 24 pregnant bitches and in the control group of nine nonpregnant bitches in the luteal phase. Fourteen of the 24 dogs had a normal pregnancy and parturition. Ten of the 24 dogs showed mucinous or colored vaginal discharge, decreased appetite, or lethargy. These initial signs of abortion or fetal resorption were noted during the fourth week of pregnancy, and the process occurred over the next 2 weeks. Progesterone and thyroxin concentrations were measured by quantitative ELISAs validated to dog serum. The serum progesterone concentrations of the group going through abortions differed significantly from the third week until the end of the eighth week. The mean serum thyroxin concentrations of healthy pregnant and nonpregnant groups significantly exceeded the reference range (20-45 nmol/L). The serum thyroxin concentrations in the abortion group were between 16.15 ± 3.17 and 40.78 ± 8.97 nmol/L. The values in this group were significantly different from the other two groups at the third week of the luteal phase. Clinical signs of abortion or fetus resorption manifested in midpregnancy. The clinical signs of abortion coincided in each case with a low serum progesterone concentration (<10 ng/mL). This phenomenon indicated, in contrast with other studies, that the decrease of serum progesterone below 10 ng/mL at the fourth week of pregnancy may signal impending abortion. In the second half of pregnancy, the thyroid gland was not able to respond adequately to the elevated requirement in thyroid hormone, although in other periods of the ovarian cycle, there were no clinical signs of hypothyroidism. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Usefulness of radioiodine scanning in patients with moderate/high risk differentiated thyroid carcinoma in whom thyroglobulin after thyroxin withdrawal is undetectable after initial treatment

    International Nuclear Information System (INIS)

    Rosario, Pedro Weslley S.; Cardoso, Ludmilla David; Fagundes, Tales Alvarenga; Reis, Janice Sepulveda; Maia, Frederico F. Ribeiro; Purisch, Saulo

    2004-01-01

    We selected 92 patients without anti thyroglobulin antibodies (TgAb), in whom thyroglobulin (Tg) after L-thyroxin withdrawal was undetectable ( 1.5 cm; and lymph nodes metastases in 43 (46.7%), local invasion in 26 (28.2%) or distant metastases in 23 (25%). Control whole-body scanning was negative in 78.2% of the cases and showed cervical uptake in the others. Cases presenting thyroid bed uptake in the absence of tumor recurrence did not receive radioiodine and Tg remained undetectable one year after the initial evaluation in all. Cervical uptake was not observed in 4/13 cases on repeated scan. In contrast, even in the absence of uptake and with undetectable Tg, 7 patients with recurrence confirmed by ultrasound (US) received surgical treatment. US showed 92.8% sensitivity for the detection of local-regional disease. The present study suggests that even moderate/high-risk patients without TgAb and with undetectable T g levels (off T 4 ) do not require radioiodine scanning after initial treatment and can be evaluated by cervical US. (author)

  2. Systematic appraisal of lactose intolerance as cause of increased need for oral thyroxine.

    Science.gov (United States)

    Cellini, Miriam; Santaguida, Maria Giulia; Gatto, Ilenia; Virili, Camilla; Del Duca, Susanna Carlotta; Brusca, Nunzia; Capriello, Silvia; Gargano, Lucilla; Centanni, Marco

    2014-08-01

    An increased need for T4 has been described in patients with different gastrointestinal disorders. However, there is a lack of systematic studies assessing the need for T4 in hypothyroid patients with lactose intolerance, a widespread and often occult disorder. The objective of the study was to assess the replacement T4 dose required in hypothyroid patients with lactose intolerance. This was a cohort study. The study was conducted at an outpatient endocrinology unit in a University Hospital. The replacement T4 dose has been analyzed, from 2009 to 2012, in 34 hypothyroid patients due to Hashimoto's thyroiditis and lactose intolerance and being noncompliant with a lactose-free diet. An individually tailored T4 dose was measured. In all patients with isolated Hashimoto's thyroiditis, target TSH (median TSH 1.02 mU/L) was obtained at a median T4 dose of 1.31 μg/kg/d. In patients with lactose intolerance, only five of 34 patients reached the desired TSH (median TSH 0.83 mU/L) with a similar T4 dose (1.29 μg/kg/d). In the remaining 29 patients, the T4 dose was progressively increased and the target TSH (median TSH 1.21 mU/L) was attained at a median T4 dose of 1.81 μg/kg/d (+38%, P lactose intolerance, a median T4 dose of 1.72 μg/kg/d (+31% P lactose intolerance significantly increased the need for oral T4 in hypothyroid patients.

  3. Serum PBDE levels in exposed rats in relation to effects on thyroxine homeostasis

    Energy Technology Data Exchange (ETDEWEB)

    Darnerud, P.O.; Aune, M.; Larsson, L.; Hallgren, S. [National Food Administration, Uppsala (Sweden)

    2004-09-15

    Brominated flame retardants (BFRs) is a group of environmental chemicals for which lately both interest and knowledge have increased considerably. Among the BFRs, the polybrominated diphenyl ethers (PBDEs) have attained special interest. Much data on environmental and human levels have been presented and several toxicological reviews are now published. Among interesting results is the difference in human PBDE levels that seem to exist between U.S.A. and Europe, results that suggest differences in exposure but without being able to pin-point the exact sources. In experimental studies PBDEs alter serum thyroxin levels, an effect seen both in rats and in mice. The mechanism(s) are still not completely clarified, but are thought to include alterations in serum transport, induced enzymatic degradation and possibly also direct effects on the thyroid gland. As perinatal alterations in thyroid homeostasis could affect brain development, early effects on thyroid hormones may be of special concern. Indeed, PBDEs have been shown to affect behaviour and learning in mice, when given neonatally. The aim of the present study was to relate the serum levels of PBDEs in rats to effects of these compounds on thyroxine homeostasis in these animals. Specifically, the relation between serum PBDE levels and effects on serum thyroxine levels was investigated, after two weeks of daily oral exposure. The result may have consequences for the future risk assessment activities on PBDE and specifically in finding the critical serum PBDE concentration at which the effect on thyroid hormone levels begin to occur.

  4. Risk of Depression, Chronic Morbidities, and l-Thyroxine Treatment in Hashimoto Thyroiditis in Taiwan

    Science.gov (United States)

    Lin, I-Ching; Chen, Hsin-Hung; Yeh, Su-Yin; Lin, Cheng-Li; Kao, Chia-Hung

    2016-01-01

    Abstract The aim of this study was to evaluate the risk of depression in and effect of l-thyroxine therapy on patients with Hashimoto thyroiditis (HT) in Taiwan. In this retrospective, nationwide cohort study, we retrieved data from the Longitudinal Health Insurance Database 2000. We collected data of 1220 patients with HT and 4880 patients without HT for the period 2000 to 2011. The mean follow-up period for the HT cohort was 5.77 years. Univariate and multivariate Cox proportional hazards regression models were used to estimate the risk of depression in the HT cohort. In the HT cohort, 89.6% of the patients were women. Compared with the non-HT cohort, the HT cohort exhibited a higher prevalence of diabetes mellitus, hyperlipidemia, and coronary artery disease. Furthermore, the HT cohort showed a higher overall incidence of depression compared with the non-HT cohort (8.67 and 5.49 per 1000 person-year; crude hazard ratio [HR] = 1.58, 95% confidence interval [CI] = 1.18–2.13). The risk of depression decreased after administration of l-thyroxine treatment for more than 1 year (adjusted HR = 1.02; 95% CI = 0.66–1.59). In Taiwan, the overall incidence of depression was greater in the young HT cohort. l-thyroxine treatment reduced the risk of depression. PMID:26871858

  5. Effects of Aroclor 1242 and different fish-based diets on vitamins A(retinol) and A2 (3,4-didehydroretinol), and their fatty acyl esters in mink plasma

    International Nuclear Information System (INIS)

    Kaekelae, Anne; Kaekelae, Reijo; Hyvaerinen Heikki; Nieminen, Petteri

    2003-01-01

    The effects of a 21-week exposure to Aroclor 1242 (1 mg per day in feed on plasma concentrations of vitamins A 1 (retinol) and A(3,4-didehydroretinol) and their principal fatty acyl esters (A 1 -16:0 A 2 -16:0 (palmitates), A 1 -18:1n-9; A 2 -18:1n-9 (oleates), and A 1 -18:0 A 2 -18:0 (stearates)) were studied in young female mink (Mustela vison) fed a diet based on freshwater smelt. These vitamin levels were also examined in mink fed diets containing Baltic herring or fatty marine fish. In the Aroclor-exposed smelt-fed mink, the plasma concentrations of A 1 and Aesters were significantly lower than the levels in controls fed the uncontaminated smelt diet. In addition, the A 2 esters reacted mor sensitively to the polychlorinated biphenyls than did A 1 esters. I contrast, in the plasma of the exposed mink the level of alcoholic A 1 was normal, and transport of thyroxine (T 4 ) and nonspecific lipoprotei transport of major lipids were not impaired. Despite the large dietary supply of vitamin A 2 and high levels of plasma A 2 esters, the mink fed freshwate smelt had only trace amounts of alcoholic vitamin A 2 in their plasma. The concentrations of A 1 and A 2 esters in the plasma of all the mink studied correlated with the hepatic total concentrations of the vitamins. Thus, in carnivores that have nonspecific lipoprotein transport of vitamin A esters determination of plasma levels of the esterified vitamins may be a useful nondestructive way to estimate stores of the vitamin A analogs in the body and to assess the organochlorine-induced decrease in the vitamin stores

  6. Intensity-modulated radiation therapy for T4 nasopharyngeal carcinoma. Treatment results and locoregional

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.L.Y.; Tsai, C.L.; Chen, W.Y.; Wang, C.W. [National Taiwan Univ. Hospital, Taipei (China). Div. of Radiation Oncology; Huang, Y.S.; Chen, Y.F. [National Taiwan Univ. Hospital, Taipei (China). Dept. of Medical Imaging; Kuo, S.H. [National Taiwan Univ. Hospital, Taipei (China). Div. of Radiation Oncology; National Taiwan Univ. College of Medicine, Taipei (China). Graduate Inst. of Clinical Medicine; Hong, R.L. [National Taiwan Univ. Hospital, Taipei (China). Div. of Medical Oncology; Ko, J.Y.; Lou, P.J. [National Taiwan Univ. Hospital, Taipei (China). Dept. of Otolaryngology

    2013-12-15

    Purpose: The purpose of this work was to examine outcomes in patients with T4 nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). Methods and materials: Between 2007 and 2010, 154 patients with nonmetastatic T4 NPC were treated with IMRT to a total dose of 70 Gy in 33-35 fractions. In addition, 97 % of patients received concurrent platinum-based chemotherapy. The median follow-up time was 52.8 months. Results: The rates of 5-year actuarial locoregional control, distant metastasis-free survival, progression free-survival, and overall survival (OS) were 81.2, 72.2, 61.9, and 78.1 %, respectively. A total of 27 patients had locoregional recurrence: 85.2 % in-field failures, 11.1 % marginal failures, and 3.7 % out-of-field failures. Fourteen patients with locoregional recurrence received aggressive treatments, including nasopharyngectomy, neck dissection, or re-irradiation, and the 5-year OS rate tended to be better (61.9 %) compared to those receiving conservative treatment (32.0 %, p = 0.051). In patients treated with 1 course of radiotherapy, grade {>=} 3 toxicities of ototoxicity, neck fibrosis, xerostomia, epistaxis, and radiographic temporal lobe necrosis occurred in 18.2, 9.8, 6.3, 2.1, and 5.6 % of patients, respectively. Increased ototoxicity, osteonecrosis, severe nasal bleeding, and temporal necrosis were observed in patients treated by re-irradiation. Conclusion: IMRT offers good locoregional control in patients with T4 NPC. For patients with locoregional recurrence after definitive radiotherapy, aggressive local treatment may be considered for a better outcome. (orig.)

  7. Specificity of interactions among the DNA-packaging machine components of T4-related bacteriophages.

    Science.gov (United States)

    Gao, Song; Rao, Venigalla B

    2011-02-04

    Tailed bacteriophages use powerful molecular motors to package the viral genome into a preformed capsid. Packaging at a rate of up to ∼2000 bp/s and generating a power density twice that of an automobile engine, the phage T4 motor is the fastest and most powerful reported to date. Central to DNA packaging are dynamic interactions among the packaging components, capsid (gp23), portal (gp20), motor (gp17, large "terminase"), and regulator (gp16, small terminase), leading to precise orchestration of the packaging process, but the mechanisms are poorly understood. Here we analyzed the interactions between small and large terminases of T4-related phages. Our results show that the gp17 packaging ATPase is maximally stimulated by homologous, but not heterologous, gp16. Multiple interaction sites are identified in both gp16 and gp17. The specificity determinants in gp16 are clustered in the diverged N- and C-terminal domains (regions I-III). Swapping of diverged region(s), such as replacing C-terminal RB49 region III with that of T4, switched ATPase stimulation specificity. Two specificity regions, amino acids 37-52 and 290-315, are identified in or near the gp17-ATPase "transmission" subdomain II. gp16 binding at these sites might cause a conformational change positioning the ATPase-coupling residues into the catalytic pocket, triggering ATP hydrolysis. These results lead to a model in which multiple weak interactions between motor and regulator allow dynamic assembly and disassembly of various packaging complexes, depending on the functional state of the packaging machine. This might be a general mechanism for regulation of the phage packaging machine and other complex molecular machines.

  8. Architecture of the bacteriophage T4 activator MotA/promoter DNA interaction during sigma appropriation.

    Science.gov (United States)

    Hsieh, Meng-Lun; James, Tamara D; Knipling, Leslie; Waddell, M Brett; White, Stephen; Hinton, Deborah M

    2013-09-20

    Gene expression can be regulated through factors that direct RNA polymerase to the correct promoter sequence at the correct time. Bacteriophage T4 controls its development in this way using phage proteins that interact with host RNA polymerase. Using a process called σ appropriation, the T4 co-activator AsiA structurally remodels the σ(70) subunit of host RNA polymerase, while a T4 activator, MotA, engages the C terminus of σ(70) and binds to a DNA promoter element, the MotA box. Structures for the N-terminal (NTD) and C-terminal (CTD) domains of MotA are available, but no structure exists for MotA with or without DNA. We report the first molecular map of the MotA/DNA interaction within the σ-appropriated complex, which we obtained by using the cleaving reagent, iron bromoacetamidobenzyl-EDTA (FeBABE). We conjugated surface-exposed, single cysteines in MotA with FeBABE and performed cleavage reactions in the context of stable transcription complexes. The DNA cleavage sites were analyzed using ICM Molsoft software and three-dimensional physical models of MotA(NTD), MotA(CTD), and the DNA to investigate shape complementarity between the protein and the DNA and to position MotA on the DNA. We found that the unusual "double wing" motif present within MotA(CTD) resides in the major groove of the MotA box. In addition, we have used surface plasmon resonance to show that MotA alone is in a very dynamic equilibrium with the MotA element. Our results demonstrate the utility of fine resolution FeBABE mapping to determine the architecture of protein-DNA complexes that have been recalcitrant to traditional structure analyses.

  9. Stimulation of the synthesis of bacteriophage T4 gene 32 protein by ultraviolet light irradiation

    International Nuclear Information System (INIS)

    Krisch, H.M.; Van Houwe, G.

    1976-01-01

    The synthesis of bacteriophage T4 gene 32 product, P32, has been followed by gel electrophoresis of lysates of infected cells which have been irradiated with ultraviolet light. In wild-type infections irradiation after the commencement of late gene expression results in a rapid stimulation of the rate of P32 synthesis. Within four minutes after irradiation P32 is synthesized at 11 times the rate of the unirradiated control infection. P32 seems to be the only T4 protein which exhibits such u.v. inducibility. This inducibility is dependent on the function of genes 46 and 47 and to a lesser extent on several other T4 genes thought to be involved in repair (P43, w and y). An infection defective in both P43 and P46 shows essentially no stimulation of the rate of P32 synthesis after irradiation. In the absence of DNA replication the parental DNA is degraded after irradiation in a dose-dependent manner. The extent of P32 induction in such an infection is also proportional to the dose. It is suggested that the production of gaps during repair of u.v.-irradiated DNA is responsible for the stimulation of P32 synthesis. A model is proposed in which such regions of single-stranded DNA compete for P32 by binding it nonspecifically, thus reducing the amount of P32 free to block the expression of gene 32. Because the expression of gene 32 is self-regulatory this would result in increased P32 synthesis. The possible role of P32 in the repair of u.v.-damaged DNA is discussed. (author)

  10. Intensity-modulated radiation therapy for T4 nasopharyngeal carcinoma. Treatment results and locoregional

    International Nuclear Information System (INIS)

    Chen, J.L.Y.; Tsai, C.L.; Chen, W.Y.; Wang, C.W.; Huang, Y.S.; Chen, Y.F.; Kuo, S.H.; National Taiwan Univ. College of Medicine, Taipei; Hong, R.L.; Ko, J.Y.; Lou, P.J.

    2013-01-01

    Purpose: The purpose of this work was to examine outcomes in patients with T4 nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). Methods and materials: Between 2007 and 2010, 154 patients with nonmetastatic T4 NPC were treated with IMRT to a total dose of 70 Gy in 33-35 fractions. In addition, 97 % of patients received concurrent platinum-based chemotherapy. The median follow-up time was 52.8 months. Results: The rates of 5-year actuarial locoregional control, distant metastasis-free survival, progression free-survival, and overall survival (OS) were 81.2, 72.2, 61.9, and 78.1 %, respectively. A total of 27 patients had locoregional recurrence: 85.2 % in-field failures, 11.1 % marginal failures, and 3.7 % out-of-field failures. Fourteen patients with locoregional recurrence received aggressive treatments, including nasopharyngectomy, neck dissection, or re-irradiation, and the 5-year OS rate tended to be better (61.9 %) compared to those receiving conservative treatment (32.0 %, p = 0.051). In patients treated with 1 course of radiotherapy, grade ≥ 3 toxicities of ototoxicity, neck fibrosis, xerostomia, epistaxis, and radiographic temporal lobe necrosis occurred in 18.2, 9.8, 6.3, 2.1, and 5.6 % of patients, respectively. Increased ototoxicity, osteonecrosis, severe nasal bleeding, and temporal necrosis were observed in patients treated by re-irradiation. Conclusion: IMRT offers good locoregional control in patients with T4 NPC. For patients with locoregional recurrence after definitive radiotherapy, aggressive local treatment may be considered for a better outcome. (orig.)

  11. Uptake of thyroxine in cultured anterior pituitary cells of euthyroid rats

    NARCIS (Netherlands)

    M.E. Everts (Maria); R. Docter (Roel); E.P.C.M. Moerings (Ellis); P.M. van Koetsveld (Peter); T.J. Visser (Theo); E.P. Krenning (Eric); G. Hennemann; M. de Jong (Marcel)

    1994-01-01

    textabstractThe uptake of [125I]T4 was investigated in cultured anterior pituitary cells isolated from adult fed Wistar rats and cultured for 3 days in medium containing 10% fetal calf serum. Experiments were performed with [125I]T4 (10(5) to 2 x 10(6) cpm; 0.35-7 nM)

  12. Laser shock peening on a 6056-T4 aluminium alloy for airframe applications

    CSIR Research Space (South Africa)

    Glaser, D

    2014-03-01

    Full Text Available stream_source_info Pityana1_2014_ABSTRACT ONLY.pdf.txt stream_content_type text/plain stream_size 1356 Content-Encoding ISO-8859-1 stream_name Pityana1_2014_ABSTRACT ONLY.pdf.txt Content-Type text/plain; charset=ISO-8859-1... Laser Shock Peening on a 6056-T4 Aluminium Alloy for Airframe Applications Daniel Glaser, Claudia Polese, Rachana D. Bedekar, Jasper Plaisier,Sisa Pityana, Bathusile Masina, Tebogo Mathebula, and Enrico Troiani Keywords: Laser Shock Peening...

  13. Characterization of bacteriophage KVP40 and T4 RNA ligase 2

    International Nuclear Information System (INIS)

    Yin Shenmin; Kiong Ho, C.; Miller, Eric S.; Shuman, Stewart

    2004-01-01

    Bacteriophage T4 RNA ligase 2 (Rnl2) exemplifies a subfamily of RNA strand-joining enzymes that includes the trypanosome RNA editing ligases. A homolog of T4 Rnl2 is encoded in the 244-kbp DNA genome of vibriophage KVP40. We show that the 335-amino acid KVP40 Rnl2 is a monomeric protein that catalyzes RNA end-joining through ligase-adenylate and RNA-adenylate (AppRNA) intermediates. In the absence of ATP, pre-adenylated KVP40 Rnl2 reacts with an 18-mer 5'-PO 4 single-strand RNA (pRNA) to form an 18-mer RNA circle. In the presence of ATP, Rnl2 generates predominantly AppRNA. Isolated AppRNA can be circularized by KVP40 Rnl2 in the absence of ATP. The reactivity of phage Rnl2 and the distribution of the products are affected by the length of the pRNA substrate. Whereas 18-mer and 15-mer pRNAs undergo intramolecular sealing by T4 Rnl2 to form monomer circles, a 12-mer pRNA is ligated intermolecularly to form dimers, and a 9-mer pRNA is unreactive. In the presence of ATP, the 15-mer and 12-mer pRNAs are converted to AppRNAs, but the 9-mer pRNA is not. A single 5' deoxynucleotide substitution of an 18-mer pRNA substrate has no apparent effect on the 5' adenylation or circularization reactions of T4 Rnl2. In contrast, a single deoxyribonucleoside at the 3' terminus strongly and selectively suppresses the sealing step, thereby resulting in accumulation of high levels of AppRNA in the absence of ATP. The ATP-dependent 'capping' of RNA with AMP by Rnl2 is reminiscent of the capping of eukaryotic mRNA with GMP by GTP:RNA guanylyltransferase and suggests an evolutionary connection between bacteriophage Rnl2 and eukaryotic RNA capping enzymes

  14. Template-directed ligation of tethered mononucleotides by t4 DNA ligase for kinase ribozyme selection.

    Directory of Open Access Journals (Sweden)

    David G Nickens

    Full Text Available BACKGROUND: In vitro selection of kinase ribozymes for small molecule metabolites, such as free nucleosides, will require partition systems that discriminate active from inactive RNA species. While nucleic acid catalysis of phosphoryl transfer is well established for phosphorylation of 5' or 2' OH of oligonucleotide substrates, phosphorylation of diffusible small molecules has not been demonstrated. METHODOLOGY/PRINCIPAL FINDINGS: This study demonstrates the ability of T4 DNA ligase to capture RNA strands in which a tethered monodeoxynucleoside has acquired a 5' phosphate. The ligation reaction therefore mimics the partition step of a selection for nucleoside kinase (deoxyribozymes. Ligation with tethered substrates was considerably slower than with nicked, fully duplex DNA, even though the deoxynucleotides at the ligation junction were Watson-Crick base paired in the tethered substrate. Ligation increased markedly when the bridging template strand contained unpaired spacer nucleotides across from the flexible tether, according to the trends: A(2>A(1>A(3>A(4>A(0>A(6>A(8>A(10 and T(2>T(3>T(4>T(6 approximately T(1>T(8>T(10. Bridging T's generally gave higher yield of ligated product than bridging A's. ATP concentrations above 33 microM accumulated adenylated intermediate and decreased yields of the gap-sealed product, likely due to re-adenylation of dissociated enzyme. Under optimized conditions, T4 DNA ligase efficiently (>90% joined a correctly paired, or TratioG wobble-paired, substrate on the 3' side of the ligation junction while discriminating approximately 100-fold against most mispaired substrates. Tethered dC and dG gave the highest ligation rates and yields, followed by tethered deoxyinosine (dI and dT, with the slowest reactions for tethered dA. The same kinetic trends were observed in ligase-mediated capture in complex reaction mixtures with multiple substrates. The "universal" analog 5-nitroindole (dNI did not support ligation when

  15. Glasgow Prognostic Score as a Prognostic Clinical Marker in T4 Esophageal Squamous Cell Carcinoma.

    Science.gov (United States)

    Ohira, Masaichi; Kubo, Naoshi; Masuda, Go; Yamashita, Yoshito; Sakurai, Katsunobu; Toyokawa, Takahiro; Tanaka, Hiroaki; Muguruma, Kazuya; Hirakawa, Kosei

    2015-09-01

    Patients with clinical T4 esophageal squamous cell carcinoma (ESCC) have an unfavorable prognosis, mainly indicated by the response to chemoradiotherapy (CRT), crucial to estimating long-term survival. Other prognostic measures include systemic inflammatory or immunonutritional indices such as the Glasgow Prognostic Score (GPS) and Prognostic Nutritional Index (PNI) that have not been sufficiently documented. This study retrospectively evaluated 91 patients with T4 ESCC treated at our Hospital between 2000 and 2013. All patients initially received CRT, including 5-fluorouracil (5FU) and cisplatin or nedaplatin with concurrent 2-Gy/fraction radiation (total dose, 40-60 Gy). Curative tumor resection was undertaken in suitable patients on completing CRT. Patients were classified as GPS0, GPS1, or GPS2 based on C-reactive protein (CRP) ≤ 10 mg/l and albumin ≥ 35 g/l, CRP >10 mg/l or albumin l, or CRP >10 mg/l and albumin l, respectively. PNI was calculated as 10-times the serum albumin (g/dl)+0.005 × total lymphocyte count (/mm(3)). The impact of the pre-treatment GPS and PNI on the prognosis of patients with T4 ESCC was investigated in univariate and multivariate analyses. Sixty (67%) patients responded to CRT (9 complete responses and 51 partial responses). Forty-one (45%) patients also underwent surgical resection of the residual tumor. The overall 5-year survival rate and median survival time were 27.0% and 11.8 months, respectively. In the cohort of CRT-plus-surgical resection, the 5-year survival rate was significantly higher than in the groups treated with CRT-alone (51.1% vs. 6.5%; p GPS1/2 (HR=2.151, p=0.015), and surgical resection (HR=0.282, pGPS is a useful, simple survival marker for patients with T4 ESCC undergoing multimodal therapy. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  16. T-4 handbook of material properties data bases. Volume 1c. Equations of state

    International Nuclear Information System (INIS)

    Holian, K.S.

    1984-11-01

    This manual is a compilation of descriptions of the equations of state (EOS) in the T-4 computerized library of material properties tables. The introduction gives a brief descriptions of the library and of the physics theories and models which were used to calculate the equations of state. Then each EOS is described in detail. First, various physical parameters of each theoretical EOS are tabulated and compared with experiments when available. Then the method of generating the EOS is briefly described. Finally, the tabels are plotted in terms of pressure and energy vs density along line of constant temperature

  17. DENV gene of bacteriophage T4 codes for both pyrimidine dimer-DNA glycosylase and apyrimidinic endonuclease activities

    International Nuclear Information System (INIS)

    McMillan, S.; Edenberg, H.J.; Radany, E.H.; Friedberg, R.C.; Friedberg, E.C.

    1981-01-01

    Recent studies have shown that purified preparations of phage T4 UV DNA-incising activity (T4 UV endonuclease or endonuclease V of phase T4) contain a pyrimidine dimer-DNA glycosylase activity that catalyzes hydrolysis of the 5' glycosyl bond of dimerized pyrimidines in UV-irradiated DNA. Such enzyme preparations have also been shown to catalyze the hydrolysis of phosphodiester bonds in UV-irradiated DNA at a neutral pH, presumably reflecting the action of an apurinic/apyrimidinic endonuclease at the apyrimidinic sites created by the pyrimidine dimer-DNA glycosylase. In this study we found that preparations of T4 UV DNA-incising activity contained apurinic/apyrimidinic endonuclease activity that nicked depurinated form I simian virus 40 DNA. Apurinic/apyrimidinic endonuclease activity was also found in extracts of Escherichia coli infected with T4 denV + phage. Extracts of cells infected with T4 denV mutants contained significantly lower levels of apurinic/apyrimidinic endonuclease activity; these levels were no greater than the levels present in extracts of uninfected cells. Furthermore, the addition of DNA containing UV-irradiated DNA and T4 enzyme resulted in competition for pyrimidine dimer-DNA glycosylase activity against the UV-irradiated DNA. On the basis of these results, we concluded that apurinic/apyrimidinic endonuclease activity is encoded by the denV gene of phage T4, the same gene that codes for pyrimidine dimer-DNA glycosylase activity

  18. Advancements in the treatment of hypothyroidism with L-T4 liquid formulation or soft gel capsule: an update.

    Science.gov (United States)

    Fallahi, Poupak; Ferrari, Silvia Martina; Ruffilli, Ilaria; Ragusa, Francesca; Biricotti, Marco; Materazzi, Gabriele; Miccoli, Paolo; Antonelli, Alessandro

    2017-05-01

    The most recent advance concerning levothyroxine (L-T4) therapy is the development of novel oral formulations: the liquid preparation, and the soft gel capsule. Areas covered: This review evaluates the most recent clinical studies about these new formulations. The liquid formulation has been shown to overcome: the food and beverages intereference with L-T4 tablets absorption, caused by food or coffee at breakfast; malabsorption induced by the increased gastric pH, resulting from atrophic gastritis, or due to proton-pump inhibitors; and malabsorption after bariatric surgery. The use of liquid L-T4 has been studied also in pregnancy, newborns and infants, suggesting a better bioequivalence than tablets. Finally, liquid L-T4 is more active than tablets in the control of thyroid-stimulating hormone (TSH) in hypothyroid patients without malabsorption, drug interference, or gastric disorders, leading to a hypothesized higher absorption of liquid L-T4 also in these patients. Few studies have evaluated soft gel L-T4 with promising results in patients with malabsorption related to coffee or gastritis. Expert opinion: Liquid L-T4 (and soft gel capsules) are more active than the tablet L-T4 in the control of TSH in hypothyroid patients with gastric disorders, malabsorption, or drug interference, but also in patients without absorption disorders.

  19. Combination treatment with T4 and T3: toward personalized replacement therapy in hypothyroidism?

    Science.gov (United States)

    Biondi, Bernadette; Wartofsky, Leonard

    2012-07-01

    Levothyroxine therapy is the traditional lifelong replacement therapy for hypothyroid patients. Over the last several years, new evidence has led clinicians to evaluate the option of combined T(3) and T(4) treatment to improve the quality of life, cognition, and peripheral parameters of thyroid hormone action in hypothyroidism. The aim of this review is to assess the physiological basis and the results of current studies on this topic. We searched Medline for reports published with the following search terms: hypothyroidism, levothyroxine, triiodothyronine, thyroid, guidelines, treatment, deiodinases, clinical symptoms, quality of life, cognition, mood, depression, body weight, heart rate, cholesterol, bone markers, SHBG, and patient preference for combined therapy. The search was restricted to reports published in English since 1970, but some reports published before 1970 were also incorporated. We supplemented the search with records from personal files and references of relevant articles and textbooks. Parameters analyzed included the rationale for combination treatment, the type of patients to be selected, the optimal T(4)/T(3) ratio, and the potential benefits of this therapy on symptoms of hypothyroidism, quality of life, mood, cognition, and peripheral parameters of thyroid hormone action. The outcome of our analysis suggests that it may be time to consider a personalized regimen of thyroid hormone replacement therapy in hypothyroid patients. Further prospective randomized controlled studies are needed to clarify this important issue. Innovative formulations of the thyroid hormones will be required to mimic a more perfect thyroid hormone replacement therapy than is currently available.

  20. Co-existence of freshwater and marine T4-like myoviruses in a typical subtropical estuary.

    Science.gov (United States)

    Liu, Lu; Cai, Lanlan; Zhang, Rui

    2017-11-01

    Viruses are the most abundant biological entities on Earth and play an important role in microbial community dynamics and biogeochemical cycling, yet their ecological characteristics in estuarine ecosystems are unclear. Here, virioplankton communities in a typical subtropical estuary, the Jiulong River estuary (JRE) in China, were investigated. The abundance of virioplankton ranged from 1.01 ± 0.05 × 107 to 1.62 ± 0.09 × 107 particles mL-1 in JRE, and the population size of viruses was correlated with temperature and nutrient levels. Three tailed viral morphotypes (myovirus, siphovirus and podovirus) were observed. Phylogenetic analysis showed that most of the g23 sequences in the JRE fell into three previously established groups (Marine, Paddy and Lake Groups) and two potential Estuary Groups. This demonstrates the co-existence of typical freshwater and marine T4-like myoviruses in the estuarine ecosystem, suggesting the movement of viruses and their hosts among biomes. Additionally, the spatial variation of g23 sequences suggests a geographic distribution pattern of T4-like myoviruses in the JRE, which might be shaped by the environmental gradient and/or their host distribution. These results provide valuable insights into the abundance, diversity and distribution patterns of virioplankton, as well as the factors influencing them, in subtropical estuarine ecosystems. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Hormonal evaluation of T4 and T3 through radioimmunoassay in younglings of rats with hypothyroidism

    International Nuclear Information System (INIS)

    Silveira, M.F.G.; Silva, I.M.S.; Pereira, S.S.L.; Souza, G.M.L.; Carvalho, E.F.M.B.; Cavalcante, C.V.G.; Lima Filho, G.L.; Catanho, M.T.J.A.

    2000-01-01

    The onset of fetal thyroid function occurs about 17-18 days after conception in the rat. The maternal hypothyroidism which occurs during gestation provokes alteration in the rat after birth. Due to this alteration, we decided to analyze the hormonal modification in the newborn rats. The hypothyroidism was induced in normal dams, which were being treated for 7 days with MMI (in the concentration of 0,03% in drinking water) before mating. Another dam group which was submitted to an induction of hypothyroidism maintained the treatment with MMI for 13 days during gestation. The hormones were assessed by radioimmunoassay technique. It was seen that the rats which were born from hypothyroid dams suffered alterations on its T 4 and T 3 hormone levels concerning to 10, 30 and 60 days after birth. There was also modifications on their weight and size. The growth is affected throughout post-natal life by thyroid hormones, which has a facilitator influence on growth hormone economy, as opposed to the inhibitory effects on TSH economy. The administration of MMI bars the fetal thyroid gland function, causing a decrease of both T 4 and T 3 levels, even after the birth, indicating that the maternal hypothyroidism influences on the post-natal life of the rat. (author)

  2. Severe Hyperthyroidism Complicated by Agranulocytosis Treated with Therapeutic Plasma Exchange: Case Report and Review of the Literature.

    Science.gov (United States)

    Garla, Vishnu; Kovvuru, Karthik; Ahuja, Shradha; Palabindala, Venkatataman; Malhotra, Bharat; Abdul Salim, Sohail

    2018-01-01

    To present a case of Graves' disease complicated by methimazole induced agranulocytosis treated with therapeutic plasma exchange (TPE) and review of the literature. A 21-year-old patient with a history of Graves' disease presented to the endocrine clinic. His history was significant for heat intolerance, weight loss, and tremors. Upon examination he had tachycardia, smooth goiter, thyroid bruit, and hyperactive reflexes. He was started on methimazole and metoprolol and thyroidectomy was to be done once his thyroid function tests normalized. On follow-up, the patient symptoms persisted. Complete blood count done showed a white blood cell count of 2100 (4000-11,000 cells/cu mm) with a neutrophil count of 400 cells/cu mm, consistent with neutropenia. He was admitted to the hospital and underwent 3 cycles of TPE and was also given filgrastim. He improved clinically and his thyroxine (T4) levels also came down. Thyroidectomy was done. He was discharged on levothyroxine for postsurgical hypothyroidism. Plasmapheresis may be useful in the treatment of hyperthyroidism. It works by removing protein bound hormones and also possibly inflammatory cytokines. Further studies are needed to clarify the role of various modalities of TPE in the treatment of hyperthyroidism.

  3. Severe Hyperthyroidism Complicated by Agranulocytosis Treated with Therapeutic Plasma Exchange: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Vishnu Garla

    2018-01-01

    Full Text Available Aim. To present a case of Graves’ disease complicated by methimazole induced agranulocytosis treated with therapeutic plasma exchange (TPE and review of the literature. Case Presentation. A 21-year-old patient with a history of Graves’ disease presented to the endocrine clinic. His history was significant for heat intolerance, weight loss, and tremors. Upon examination he had tachycardia, smooth goiter, thyroid bruit, and hyperactive reflexes. He was started on methimazole and metoprolol and thyroidectomy was to be done once his thyroid function tests normalized. On follow-up, the patient symptoms persisted. Complete blood count done showed a white blood cell count of 2100 (4000–11,000 cells/cu mm with a neutrophil count of 400 cells/cu mm, consistent with neutropenia. He was admitted to the hospital and underwent 3 cycles of TPE and was also given filgrastim. He improved clinically and his thyroxine (T4 levels also came down. Thyroidectomy was done. He was discharged on levothyroxine for postsurgical hypothyroidism. Conclusion. Plasmapheresis may be useful in the treatment of hyperthyroidism. It works by removing protein bound hormones and also possibly inflammatory cytokines. Further studies are needed to clarify the role of various modalities of TPE in the treatment of hyperthyroidism.

  4. Low submetamorphic doses of dexamethasone and thyroxine induce complete metamorphosis in the axolotl (Ambystoma mexicanum) when injected together.

    Science.gov (United States)

    Kühn, Eduard R; De Groef, Bert; Grommen, Sylvia V H; Van der Geyten, Serge; Darras, Veerle M

    2004-06-01

    Entanglement of functions between the adrenal (or interrenal) and thyroid axis has been well described for all vertebrates and can be tracked down up to the level of gene expression. Both thyroid hormones and corticosteroids may induce morphological changes leading to metamorphosis climax in the neotenic Mexican axolotl (Ambystoma mexicanum). In a first series of experiments, metamorphosis was induced with an injection of 25 microg T(4) on three alternate days as judged by a decrease in body weight and tail height together with complete gill resorption. This injection also resulted in elevated plasma concentrations of T(3) and corticosterone. Previous results have indicated that the same dose of dexamethasone (DEX) is ineffective in this regard (Gen. Comp. Endocrinol. 127 (2002) 157). In a second series of experiments low doses of T(4) (0.5 microg) or DEX (5 microg) were ineffective to induce morphological changes. However, when these submetamorphic doses were injected together, morphological changes were observed within one week leading to complete metamorphosis. It is concluded that thyroid hormones combined with corticosteroids are essential for metamorphosis in the axolotl and that only high doses of either thyroid hormone or corticosteroid can induce morphological changes when injected separately.

  5. Bacteriophage T4 Infection of Stationary Phase E. coli: Life after Log from a Phage Perspective

    Directory of Open Access Journals (Sweden)

    Elizabeth Martin Kutter

    2016-09-01

    Full Text Available Virtually all studies of phage infections investigate bacteria growing exponentially in rich media. In nature, however, phages largely encounter non-growing cells. Bacteria entering stationary phase often activate well-studied stress defense mechanisms that drastically alter the cell, facilitating its long-term survival. An understanding of phage-host interactions in such conditions is of major importance from both an ecological and therapeutic standpoint. Here, we show that bacteriophage T4 can efficiently bind to, infect and kill E. coli in stationary phase, both in the presence and absence of a functional stationary-phase sigma factor, and explore the response of T4-infected stationary phase cells to the addition of fresh nutrients 5 or 24 hours after that infection. An unexpected new mode of response has been identified. Hibernation mode is a persistent but reversible dormant state in which the infected cells make at least some phage enzymes, but halt phage development until appropriate nutrients become available before producing phage particles. Our evidence indicates that the block in hibernation mode occurs after the middle-mode stage of phage development; host DNA breakdown and the incorporation of the released nucleotides into phage DNA indicate that the enzymes of the nucleotide synthesizing complex, under middle-mode control, have been made and assembled into a functional state. Once fresh glucose and amino acids become available, the standard lytic infection process rapidly resumes and concentrations of up to 1011 progeny phage (an average of about 40 phage per initially-present cell are produced. All evidence is consistent with the hibernation-mode control point lying between middle mode and late mode T4 gene expression. We have also observed a scavenger response, where the infecting phage takes advantage of whatever few nutrients are available to produce small quantities of progeny within 2 to 5 hours after infection. The scavenger

  6. Experimental and computational studies on the DNA translocation mechanism of the T4 viral packaging motor

    Science.gov (United States)

    Migliori, Amy; Arya, Gaurav; Smith, Douglas E.

    2012-10-01

    Bacteriophage T4 is a double stranded DNA virus that infects E.coli by injecting the viral genome through the cellular wall of a host cell. The T4 genome must be ejected from the viral capsid with sufficient force to ensure infection. To generate high ejection forces, the genome is packaged to high density within the viral capsid. A DNA translocation motor, in which the protein gp17 hydrolyzes ATP and binds to the DNA, is responsible for translocating the genome into the capsid during viral maturation of T4. This motor generates forces in excess of 60 pN and packages DNA at rates exceeding 2000 base pairs/second (bp/s)1. Understanding these small yet powerful motors is important, as they have many potential applications. Though much is known about the activity of these motors from bulk and single molecule biophysical techniques, little is known about their detailed molecular mechanism. Recently, two structures of gp17 have been obtained: a high-resolution X-ray crystallographic structure showing a monomeric compacted form of the enzyme, and a cryo-electron microscopic structure of the extended form of gp17 in complex with actively packaging prohead complexes. Comparison of these two structures indicates several key differences, and a model has been proposed to explain the translocation action of the motor2. Key to this model are a set of residues forming ion pairs across two domains of the gp17 molecule that are proposed to be involved in force generation by causing the collapse of the extended form of gp17. Using a dual optical trap to measure the rates of DNA packaging and the generated forces, we present preliminary mutational data showing that these several of these ion pairs are important to motor function. We have also performed preliminary free energy calculations on the extended and collapsed state of gp17, to confirm that these interdomain ion pairs have large contributions to the change in free energy that occurs upon the collapse of gp17 during the

  7. Quantification of thyroxine by the selective photoluminescence quenching of L-cysteine–ZnS quantum dots in aqueous solution containing hexadecyltrimethylammonium bromide

    International Nuclear Information System (INIS)

    Khan, Sarzamin; Carneiro, Leonardo S.A.; Romani, Eric C.; Larrudé, Dunieskys G.; Aucelio, Ricardo Q.

    2014-01-01

    The determination of L-thyroxine is proposed based on the photoluminescence quenching effect caused on the L-cysteine modified ZnS quantum dots (L-cysteine ZnS QDs) aqueous dispersion. Under optimum conditions, the analytical response followed a Stern–Volmer model and the experimental conditions were adjusted to enable a robust and reproducible photoluminescence signal. The linear response observed in the quantum dots aqueous dispersion covered the L-thyroxine concentration from the LOQ (2.0×10 −8 mol L −1 ) to 4.0×10 −6 mol L −1 . The approach was tested in the determination of L-thyroxine in pharmaceutical formulations used to treat patients with thyroid gland disorder. The percent recoveries in controlled samples were between 93.3 and 103%. Analyte fortified saliva was also evaluated as a possible sample for L-thyroxine monitoring of a patient under treatment. It was identified a static type of photoluminescence quenching caused by L-thyroxine. - Highlights: • L-cysteine ZnS QDs were used as a photoluminescent probe to detect L-thyroxine. • Intensity of probe decreases following a Stern–Volmer model. • The method can detect down ng L −1 levels of L-thyroxine in the probe dispersion. • Method was used to determinate of L-thyroxine in saliva and in pharmaceuticals. • Mechanism of interaction between L-thyroxine and quantum dots was studied

  8. Modelling T4 cell count as a marker of HIV progression in the absence of any defence mechanism

    Directory of Open Access Journals (Sweden)

    VSS Yadavalli

    2010-12-01

    Full Text Available The T4 cell count, which is considered one of the markers of disease progression in an HIV infected individual, is modelled in this paper. The World Health Organisation has recently advocated that countries encourage HIV infected individuals to commence antiretroviral treatments once their T4 cell count drops below 350 cells per ml of blood (this threshold was formerly 200 cells per ml of blood. This recommendation is made because when the T4 cell count is low, the T4 cells are unable to mount an effective immune response against antigens and any such foreign matters in the body, and consequently the individual becomes susceptible to opportunistic infections and lymphomas. A stochastic catastrophe model is developed in this paper to obtain the mean, variance and covariance of the uninfected, infected and lysed T4 cells. The amount of toxin produced in an HIV infected person from the time of infection to a later time may also be obtained from the model. Numerical illustrations of the correlation structures between uninfected and infected T4 cells, and between the infected and lysed T4 cells are also presented.

  9. Simultaneous quantification of T4, T3, rT3, 3,5-T2 and 3,3'-T2 in larval zebrafish (Danio rerio) as a model to study exposure to polychlorinated biphenyls.

    Science.gov (United States)

    Chen, Xiaopeng; Walter, Kyla M; Miller, Galen W; Lein, Pamela J; Puschner, Birgit

    2018-06-01

    Environmental toxicants that interfere with thyroid hormone (TH) signaling can impact growth and development in animals and humans. Zebrafish represent a model to study chemically induced TH disruption, prompting the need for sensitive detection of THs. Simultaneous quantification of 3,3',5-triiodo-l-thyronine (T3), thyroxine (T4), 3,3',5'-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2) and 3,3'-diiodo-l-thyronine (3,3'-T2) in zebrafish larvae was achieved by ultra-performance liquid chromatography-tandem mass spectrometry in positive ion mode. Solid-phase extraction with SampliQ cartridges and derivatization with 3 m hydrochloric acid in n-butanol reduced matrix effects. Derivatized compounds were separated on an Acquity UPLC BEH C 18 column with mobile phases consisting of 0.1% acetic acid in deionized water and 0.1% acetic acid in methanol. The limits of detection ranged from 0.5 to 0.6 pg injected on column. The method was validated by evaluating recovery (77.1-117.2%), accuracy (87.3-123.9%) and precision (0.5-12.4%) using diluted homogenized zebrafish embryos spiked with all target compounds. This method was then applied to zebrafish larvae collected after 114 h of exposure to polychlorinated biphenyls (PCBs), including PCB 28, PCB 66 and PCB 95, or the technical mixture Aroclor 1254. Exposure to PCB 28 and PCB 95 increased the T4:T3 ratio and decreased the T3:rT3 ratio, demonstrating that this method can effectively detect PCB-induced alterations in THs. Copyright © 2018 John Wiley & Sons, Ltd.

  10. [After the Action T4 : "Regionalized euthanasia" in the Günzburg Psychiatric Hospital].

    Science.gov (United States)

    Söhner, F; V Cranach, M; Fangerau, H; Becker, T

    2017-09-01

    In Bavarian psychiatric hospitals approximately 15,000 people with mental handicaps and mental illnesses were killed after the so-called Action T4. The Heil- und Pflegeanstalt (psychiatric hospital) Günzburg was a so-called Zwischenanstalt (interim institution). The aim of the study was to analyze its role in carrying out "regionalized euthanasia". Based on defined criteria the patient records of deceased patients at the Günzburg Psychiatric Hospital between July 1941 and December 1943 were analyzed to establish whether criteria for "regionalized euthanasia" were fulfilled. During the study period 45 patients at the Günzburg Psychiatric Hospital probably died following actions by direct or indirect intention to kill using malnutrition, neglect, medication overdose or a combination of these actions. The Günzburg Psychiatric Hospital was involved in "regionalized euthanasia".

  11. Effects of Friction Stir Welding on Corrosion Behaviors of AA2024-T4 Aluminum Alloy

    Directory of Open Access Journals (Sweden)

    Ales Steve Korakan

    2017-01-01

    Full Text Available In this work, the corrosion behavior of welded joints of AA2024-T4 Al alloy produced by friction stir welding process has been investigated. Tests were performed in an aerated 3.5% NaCl aqueous solution with pH = 7 at 20±2°C. Corrosion rate and corrosion morphology of weld regions were evaluated and compared to those of the parent metal. The microstructure of weld nugget, thermomechanical affected zone, heated affected zone, and parent metal were analyzed using scanning electron microscopy and energy dispersive spectroscopy. It was observed that corrosion initiated at FSW related spots and the sizes of local corrosion increased with time.

  12. Production of antisera and development of radioimmunoassay for serum T3, T4, and ferritin

    International Nuclear Information System (INIS)

    Elhag, Omer Mohamed Abdalla

    1998-05-01

    In this study twelve local rabbits and sixteen New-zealand rabbits were subjected to immunization against T3 and T4 immunogens. Two local sheep (ovis aris) were immunized against human liver ferritin. The T3 and T4 immunogens were prepared by conjugation of the haptens to carrier proteins (bovine serum albumin ''BSA'' and horse serum protein ''HSP''), using water soluble carboiimide as coupling agent. The local and New-zealand rabbits were immunized against these conjugates emulsified in freund's complete adjuvant (FCA) in the first and second injections, and emulsified in freund's incomplete adjuvant (FIA) in the following injections. The blood samples obtained from rabbits after each injection were tested for antibodies as well as for the effect of immunization on rabbits biochemical and haematological parameters. The blood samples obtained from sheep were tested for anti-ferritin antibodies using crude antiserum, then this antiserum was purified using ammonium sulphate. A part of it was adsorbed physically onto polystyrene beads while the other part was linked chemically to magnitisable particles inorder to develop to IRMAs. The purified antiferritin antibody was diluted 200,000 folds before being coated to polystyrene beads, and different dilutions were tried with coupling to magnetic solid phase. Optimization and validation procedures for the two IRMAs ferritin were performed. The results obtained showed poor response of rabbits to immunization against T3 and T4 immunogen conjugates, where the percent bound (B%) of tracer with the antibody ranged from (0.0-22%) for local rabbits using charcoal seperation technique, and (0.0-2.9%) using second antibody precipitation technique. The B% for the antiserum obtained from New-zealand rabbits ranged from (0.0-18.1) using second antibody precipitation technique. Serum T3, T4 and TSH of the immunized rabbits were measured and found to be not significantly different form the controls (p=0.2211, 0.098, 0.35 respectively

  13. Pecularities of mutagenesis of T4Br bacteriophage under the direct and indirect radiation effects

    International Nuclear Information System (INIS)

    Yurov, S.S.

    1975-01-01

    Different lethal and mutagenic effects were shown when bacteriophage T4Br + (470 r/min) was irradiated in broth (direct effect) and a buffer solution (direct and indirect action). The survival rate of the bacteriophage in the buffer solution was 0.1 percent for a dose rate of 60 kr; in the broth it was 10 percent. The frequency of mutation of the bacteriophage also showed the greater effect of the irradiation in the buffer solution than in the broth (25 and 5 r-mutants respectively at a dose rate of 10 kr). An analysis of the ratio of the r-groups when the bacteriophage was treated in various ways revealed differences between mutagenesis produced in the broth and the buffer, and spontaneous mutagenesis. (V.A.P.)

  14. Production of antisera and development of radioimmunoassay for serum T3, T4, and ferritin

    Energy Technology Data Exchange (ETDEWEB)

    Elhag, Omer Mohamed Abdalla [Department of Biochemistry, Faculty of Veterinary Science, University of Khartoum, Khartoum (Sudan)

    1998-05-01

    In this study twelve local rabbits and sixteen New-zealand rabbits were subjected to immunization against T3 and T4 immunogens. Two local sheep (ovis aris) were immunized against human liver ferritin. The T3 and T4 immunogens were prepared by conjugation of the haptens to carrier proteins (bovine serum albumin ``BSA`` and horse serum protein ``HSP``), using water soluble carboiimide as coupling agent. The local and New-zealand rabbits were immunized against these conjugates emulsified in freund`s complete adjuvant (FCA) in the first and second injections, and emulsified in freund`s incomplete adjuvant (FIA) in the following injections. The blood samples obtained from rabbits after each injection were tested for antibodies as well as for the effect of immunization on rabbits biochemical and haematological parameters. The blood samples obtained from sheep were tested for anti-ferritin antibodies using crude antiserum, then this antiserum was purified using ammonium sulphate. A part of it was adsorbed physically onto polystyrene beads while the other part was linked chemically to magnitisable particles inorder to develop to IRMAs. The purified antiferritin antibody was diluted 200,000 folds before being coated to polystyrene beads, and different dilutions were tried with coupling to magnetic solid phase. Optimization and validation procedures for the two IRMAs ferritin were performed. The results obtained showed poor response of rabbits to immunization against T3 and T4 immunogen conjugates, where the percent bound (B%) of tracer with the antibody ranged from (0.0-22%) for local rabbits using charcoal seperation technique, and (0.0-2.9%) using second antibody precipitation technique. The B% for the antiserum obtained from New-zealand rabbits ranged from (0.0-18.1) using second antibody precipitation technique. Serum T3, T4 and TSH of the immunized rabbits were measured and found to be not significantly different form the controls (p=0.2211, 0.098, 0.35 respectively

  15. Pollution reduction technology program for class T4(JT8D) engines

    Science.gov (United States)

    Roberts, R.; Fiorentino, A. J.; Diehl, L. A.

    1977-01-01

    The technology required to develop commercial gas turbine engines with reduced exhaust emissions was demonstrated. Can-annular combustor systems for the JT8D engine family (EPA class T4) were investigated. The JT8D turbofan engine is an axial-flow, dual-spool, moderate-bypass-ratio design. It has a two-stage fan, a four-stage low-pressure compressor driven by a three-stage low-pressure turbine, and a seven-stage high-pressure compressor driven by a single-stage high-pressure turbine. A cross section of the JT8D-17 showing the mechanical configuration is given. Key specifications for this engine are listed.

  16. Virtual unit delay for digital frequency adaptive T/4 delay phase-locked loop system

    DEFF Research Database (Denmark)

    Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

    2016-01-01

    /processor with a fixed sampling rate considering the cost and complexity, where the number of unit delays that have been adopted should be an integer. For instance, in conventional digital control systems, a single-phase T/4 Delay Phase-Locked Loop (PLL) system takes 50 unit delays (i.e., in a 50-Hz system...... Delay PLL system should be done in its implementation. This process will result in performance degradation in the digital control system, as the exactly required number of delays is not realized. Hence, in this paper, a Virtual Unit Delay (VUD) has been proposed to address such challenges to the digital......Digital micro-controllers/processors enable the cost-effective control of grid-connected power converter systems in terms of system monitoring, signal processing (e.g., grid synchronization), control (e.g., grid current and voltage control), etc. Normally, the control is implemented in a micro-controller...

  17. Thyroid hormone uptake and T4 derived T3 formation in different skeletal muscle types of normal and hyperthyroid rats

    International Nuclear Information System (INIS)

    Hardeveld, C. van; Kassenaar, A.A.H.

    1978-01-01

    In this study hind-limb perfusion was used to investigate conversion of T 4 to T 3 in skeletal muscle tissue. For this purpose the rats were depleted of thyroid hormones by thyroid ablation with 0.75 mCi 131 I and were perfused 2 weeks later, when the skeletal muscle tissue consumed oxygen at a normal rate due to one subcutaneous dose of 10 μg T 3 /100 g b. w. 3 days before the perfusion experiments were started. T 4 * of high specific activity (> 2000 μCi/μg) was added to the perfusate. In the muscle (mixed type) a mean T 4 → T 3 conversion of 2% (range 0.5-3.9) was found after 120 min of perfusion. T 3 generation from T 4 in skeletal muscle did not correspond with T 3 muscle uptake. This observation makes a significant overestimation of T 3 by selective uptake of a small contamination of T 3 * in the T 4 * preparation highly improbable. In red muscle the T 4 and T 3 uptake was about 50 % higher than in white muscle. The observed Tetracsup(c) and T 3 sup(c) were significantly higher in red than in white muscle. The uptake of thyroid hormones by both muscle types was not changed in hyperthyroid rats. The Tetrac and T 3 formation from T 4 , however, was increased in red muscles of hyperthyroid rats. The results show that thyroid hormone metabolism can vary markedly depending upon the type of muscle studied and they present a basis for a better understanding of clinical and biochemical evidence for a different susceptibility of red and white muscle fibers to thyroid hormones. (Abbreviations: *= 125 I; **= 131 I; T 3 sup(c)=T 4 derived T 3 ; Tetracsup(c)=T 4 derived Tetrac) (author)

  18. Structure-Function Analysis of the DNA Translocating Portal of the Bacteriophage T4 Packaging Machine

    Science.gov (United States)

    Padilla-Sanchez, Victor; Gao, Song; Kim, Hyung Rae; Kihara, Daisuke; Sun, Lei; Rossmann, Michael G.; Rao, Venigalla B.

    2013-01-01

    Tailed bacteriophages and herpesviruses consist of a structurally well conserved dodecameric portal at a special five-fold vertex of the capsid. The portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. Although the structures of portals from phages φ29, SPP1 and P22 have been determined, their mechanistic roles have not been well understood. Structural analysis of phage T4 portal (gp20) has been hampered because of its unusual interaction with the E. coli inner membrane. Here, we predict atomic models for the T4 portal monomer and dodecamer, and fit the dodecamer into the cryoEM density of the phage portal vertex. The core structure, like that from other phages, is cone-shaped with the wider end containing the “wing” and “crown” domains inside the phage head. A long “stem” encloses a central channel, and a narrow “stalk” protrudes outside the capsid. A biochemical approach was developed to analyze portal function by incorporating plasmid-expressed portal protein into phage heads and determining the effect of mutations on head assembly, DNA translocation, and virion production. We found that the protruding loops of the stalk domain are involved in assembling the DNA packaging motor. A loop that connects the stalk to the channel might be required for communication between the motor and portal. The “tunnel” loops that project into the channel are essential for sealing the packaged head. These studies established that the portal is required throughout the DNA packaging process, with different domains participating at different stages of genome packaging. PMID:24126213

  19. High-dose radiotherapy alone for patients with T4-stage laryngeal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mucha-Malecka, A. [Maria Sklodowska-Curie Memorial Institute, Krakow (Poland). Dept. of Radiation Oncology; Skladowski, K. [Maria Sklodowska-Curie Memorial Institute, Gliwice (Poland). Dept. of Radiation Oncology

    2013-08-15

    Background and purpose: The purpose of this retrospective study was to report on the efficacy of radiotherapy alone in patients with T4-stage laryngeal cancer and to establish the prognostic value of (a) the size and location of the extralaryngeal tumor extensions and (b) of emergency tracheostomy. Patients and methods: A group of 114 patients were treated with definitive radiotherapy between 1990 and 1996. The piriform recess was involved in 37 cases (33 %), the base of the tongue and glosso-epiglottic vallecula in 34 cases (30 %), and the hypopharyngeal wall in 10 cases (9 %). In 16 cases (14 %), emergency tracheostomy was performed before radiotherapy. The mean total dose was 68 Gy (range, 60-77.6 Gy). The mean treatment time was 49 days (range, 42-74 days). Results: Actuarial 3-year local control (LC) was noted in 42 % of patients, disease-free survival (DFS) in 35 %, and overall survival (OS) in 40 %. The best prognosis was for the lesion suspected of cartilage infiltration: 56 % 3-year LC. The worst results were noted in the cases with massive infiltrations spreading from the larynx through the hypopharynx: 13 % 3-year LC. Emergency tracheostomy before radiotherapy was significantly connected with the worst treatment results (p = 0.000): 3-year LC in patients with tracheostomy was 0 % vs. 48 % in patients without tracheostomy. Conclusion: Conventional radiotherapy of T4 laryngeal cancer is a method of treatment with limited effectiveness. The efficacy of radiotherapy is dependent on the location and extent of extralaryngeal infiltrations. Emergency tracheostomy is a prognostic factor connected with the worst prognosis. (orig.)

  20. High-dose radiotherapy alone for patients with T4-stage laryngeal cancer

    International Nuclear Information System (INIS)

    Mucha-Malecka, A.; Skladowski, K.

    2013-01-01

    Background and purpose: The purpose of this retrospective study was to report on the efficacy of radiotherapy alone in patients with T4-stage laryngeal cancer and to establish the prognostic value of (a) the size and location of the extralaryngeal tumor extensions and (b) of emergency tracheostomy. Patients and methods: A group of 114 patients were treated with definitive radiotherapy between 1990 and 1996. The piriform recess was involved in 37 cases (33 %), the base of the tongue and glosso-epiglottic vallecula in 34 cases (30 %), and the hypopharyngeal wall in 10 cases (9 %). In 16 cases (14 %), emergency tracheostomy was performed before radiotherapy. The mean total dose was 68 Gy (range, 60-77.6 Gy). The mean treatment time was 49 days (range, 42-74 days). Results: Actuarial 3-year local control (LC) was noted in 42 % of patients, disease-free survival (DFS) in 35 %, and overall survival (OS) in 40 %. The best prognosis was for the lesion suspected of cartilage infiltration: 56 % 3-year LC. The worst results were noted in the cases with massive infiltrations spreading from the larynx through the hypopharynx: 13 % 3-year LC. Emergency tracheostomy before radiotherapy was significantly connected with the worst treatment results (p = 0.000): 3-year LC in patients with tracheostomy was 0 % vs. 48 % in patients without tracheostomy. Conclusion: Conventional radiotherapy of T4 laryngeal cancer is a method of treatment with limited effectiveness. The efficacy of radiotherapy is dependent on the location and extent of extralaryngeal infiltrations. Emergency tracheostomy is a prognostic factor connected with the worst prognosis. (orig.)

  1. Is neoadjuvant chemotherapy prior to radio-chemotherapy beneficial in T4 anal carcinoma?

    Science.gov (United States)

    Moureau-Zabotto, L; Viret, F; Giovaninni, M; Lelong, B; Bories, E; Delpero, J R; Pesenti, C; Caillol, F; de Chaisemartin, C; Minsat, M; Monges, G; Sarran, A; Resbeut, M

    2011-07-01

    This study retrospectively describes the outcome of a series of 38 patients (pts) with T4 anal carcinoma exclusively treated by radio and chemotherapy. From 1992 to 2007, 38 pts with UST4-N0-2-M0 anal carcinoma were treated with exclusive radiotherapy and chemotherapy. All patients received external beam radiotherapy (EBRT) (median dose 45 Gy) with a concomitant chemotherapy (5-fluorouracil-cisplatin). Eleven patients received neo-adjuvant chemotherapy (5-fluorouracil-cisplatin). After 2-8 weeks, a 15-20 Gy boost was delivered either with EBRT (20 pts) or interstitial (192)Ir brachytherapy (18 pts). Mean follow-up was 66 months. After chemoradiation therapy (CRT), 13 pts (34%) had a complete response, 23 pts (60%) a response >50% (2 pts were not evaluated). The 5-year-disease-free survival was 79.2 ± 6.5%, and the 5-year overall survival was 83.9 ± 6%. Eight patients developed tumor progression (mean delay 8.8 months), six of them requiring a salvage surgery with definitive colostomy for local relapse. Late severe complication requiring colostomy was observed in 2 pts. The 5-year-colostomy-free survival was 78 ± 6.9%. Patients who received primary chemotherapy had a statistically significant better 5-year colostomy-free survival (100% vs. 38 ± 16.4%, P = 0.0006). T4 anal carcinoma can be treated with a curative intent using a sphincter-sparing approach of CRT, and neo-adjuvant chemotherapy should be considered prior to radiotherapy. Copyright © 2011 Wiley-Liss, Inc.

  2. Structure-function analysis of the DNA translocating portal of the bacteriophage T4 packaging machine.

    Science.gov (United States)

    Padilla-Sanchez, Victor; Gao, Song; Kim, Hyung Rae; Kihara, Daisuke; Sun, Lei; Rossmann, Michael G; Rao, Venigalla B

    2014-03-06

    Tailed bacteriophages and herpesviruses consist of a structurally well conserved dodecameric portal at a special 5-fold vertex of the capsid. The portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. Although the structures of portals from phages φ29, SPP1, and P22 have been determined, their mechanistic roles have not been well understood. Structural analysis of phage T4 portal (gp20) has been hampered because of its unusual interaction with the Escherichia coli inner membrane. Here, we predict atomic models for the T4 portal monomer and dodecamer, and we fit the dodecamer into the cryo-electron microscopy density of the phage portal vertex. The core structure, like that from other phages, is cone shaped with the wider end containing the "wing" and "crown" domains inside the phage head. A long "stem" encloses a central channel, and a narrow "stalk" protrudes outside the capsid. A biochemical approach was developed to analyze portal function by incorporating plasmid-expressed portal protein into phage heads and determining the effect of mutations on head assembly, DNA translocation, and virion production. We found that the protruding loops of the stalk domain are involved in assembling the DNA packaging motor. A loop that connects the stalk to the channel might be required for communication between the motor and the portal. The "tunnel" loops that project into the channel are essential for sealing the packaged head. These studies established that the portal is required throughout the DNA packaging process, with different domains participating at different stages of genome packaging. © 2013.

  3. Nueva Área Terminal (NAT del aeropuerto de Madrid-Barajas T-4

    Directory of Open Access Journals (Sweden)

    Lamela, A.

    2006-03-01

    Full Text Available This paper deals with the New Terminal Area of the Barajas airport. Its first part indicates the participants in the design and construction, as well as some general data. In the second part, organised like a data chart, technical data, such as general information, construction aspects, parking area, data about the building itself and others, are expressed in a concise way. The third part analyzes the construction aspects of the NAT Building, related to the power efficiency. The paper ends with a note that the author of the project has considered of interest about the functionality of the T4. Drawings, details and photographs that show the work in their total magnitude are also included.El articulo que se presenta trata de la Nueva Área Terminal (NAT del aeropuerto de Barajas y está diferenciado en una primera parte, donde se indican los créditos del proyecto y de la construcción, así como algunos datos generales. En el punto 2 y organizado como ficha, aparecen de forma escueta los datos técnicos, tales como: información general, sobre la construcción, sobre los aparcamientos, sobre el edificio terminal y otras. En el punto 3 se analizan los aspectos de la edificación NAT, relacionados con la eficiencia energética y finaliza el artículo con una nota sobre la funcionalidad de la T4, que el autor del proyecto ha considerado de interés. Se incluyen planos detalles y fotografías que muestran la obra en su total magnitud.

  4. Evaluation of Selected Atherosclerosis Risk Factors in Women with Subclinical Hypothyroidism Treated with L-Thyroxine.

    Science.gov (United States)

    Adamarczuk-Janczyszyn, Maria; Zdrojowy-Wełna, Aleksandra; Rogala, Natalia; Zatońska, Katarzyna; Bednarek-Tupikowska, Grażyna

    2016-01-01

    Subclinical hypothyroidism (SCH) is a common endocrine disorder, probably increasing cardiovascular (CV) risk. However, the relation between SCH and atherosclerosis risk factors remains unclear. The aim of the study was to evaluate selected atherosclerosis risk factors in women with SCH in comparison to a group of healthy women and women with overt hypothyroidism, as well as to investigate the influence of L-thyroxine replacement on those risk factors. The study group consisted of 187 obese women aged between 50 and 70 years: 100 women with SCH, 45 women with overt hypothyroidism and 42 women with TSH level in reference ranges. Anthropometric parameters were evaluated. Laboratory tests included thyroid hormones concentrations, lipid profile with apolipoproteins, CRP, homocysteine. Atherosclerotic indexes were calculated: LDL C/HDL C ratio, apoA1/apoB ratio and Castelli risk index. Women with hypothyroidism were given L-thyroxine treatment and after 6 months in euthyroidism the evaluation was repeated. Total cholesterol, LDL-cholesterol and triglycerides concentrations as well as LDL-C/HDL-C ratio and Castelli index were higher in SCH than in controls and decreased after L-thyroxin substitution. All of the calculated atherosclerosis indexes showed significant positive correlations with TSH concentration in SCH group. Also in this group the systolic and diastolic blood pressure decreased significantly after treatment. Dyslipidemia in obese SCH women is not severe, but if untreated for many years, it may lead to atherosclerosis. Substitution therapy improves the lipid profile, changing the relations between protective and proatherogenic fractions of serum lipids, and optimises blood pressure.

  5. In vitro thyroid testing in populations with low thyroxine binding globulin capacity

    Energy Technology Data Exchange (ETDEWEB)

    Cuaron, A

    1993-12-31

    Total thyroxine (T{sub 4}) concentration in serum is a reliable indicator of thyroid function in most individuals, but it is affected by altered concentrations of thyroxine-binding globulin (TBG) in serum. Within certain limits, the variations in total TBG binding capacity (TBG{sub TOTAL}) caused by the fluctuations in the concentration of this binding globulin in serum can be modulated by calculating the free thyroxine index (FT{sub 4}I) as the product of T{sub 4} and the in vitro uptake of triiodothyronine by a secondary binder (T{sub 3}U). This calculation is empirically based on the facts that free TBG binding capacity (TBG{sub FREE}) is inversely related to T{sub 3}U and that T{sub 4} and T{sub 3}U show opposite behaviour when measured in sera with altered TBG: a low T{sub 4} in serum with reduced TBG{sub TOTAL} is compensated by a high value for T{sub 3}U, while an elevated T{sub 4} in serum with increased TBG{sub TOTAL} is compensated by a low value for T{sub 3}U. In both cases the product of T{sub 4} and T{sub 3} renders a normal FT{sub 4}I value, showing a certain association with the concentration of free T{sub 4} in serum (FT{sub 4}). In fact, this index has been shown to be superior than several FT{sub 4} assay systems in the assessment of thyroid status in clinical euthyroid subjects with relatively high or low T{sub 3}U 3 figs, 4 tabs

  6. Effects of early thyroxine treatment on development and growth at age 10.7 years: follow-up of a randomized placebo-controlled trial in children with Down's syndrome.

    Science.gov (United States)

    Marchal, Jan Pieter; Maurice-Stam, Heleen; Ikelaar, Nadine A; Klouwer, Femke C C; Verhorstert, Kim W J; Witteveen, M Emma; Houtzager, Bregje A; Grootenhuis, Martha A; van Trotsenburg, A S Paul

    2014-12-01

    In 2-year-old children with Down's syndrome (DS), early T4 treatment was found to result in slightly better motor development and growth. This study sought to determine long-term effects of early T4 treatment on development and growth in children with DS with either an elevated or normal neonatal TSH concentration. Patients received a single follow-up visit 8.7 years after a randomized placebo-controlled trial (RCT) comparing T4 and placebo treatment during the first 2 years of life. Dutch Academic Hospital. All children who completed the RCT (N = 181, of 196 randomly assigned children) were invited for the follow-up study. A total of 123 participants enrolled, at a mean age of 10.7 years. T4 or placebo treatment from the neonatal period until 2 years. Primary: mental and motor development. Secondary: communication skills, fine-motor coordination, height, weight, and head circumference (HC). Outcomes were compared between T4- and placebo-treated children, and between treatment groups with either a normal (development, communication skills, or fine-motor coordination did not differ between T4- (N = 64) and placebo-treated children (N = 59). T4-treated children had a larger HC (50.4 vs 49.8 cm, P = .04) and tended to be taller (133.2 vs 131.1 cm, P = .06). These differences were somewhat greater in children with TSH ≥ 5 mIU/L (HC: T4, 50.5 vs placebo, 49.7 cm; P = .01; height: T4, 133.8 vs placebo, 130.8 cm; P = .02), but were not found in children with TSH children with DS does not seem to benefit mental or motor development later in life. However, the positive effect on growth is still measurable, especially in children with an elevated plasma TSH concentration in the neonatal period.

  7. Contribution to the microchemical determination of thyroxine and triiodothyronine in urine

    Energy Technology Data Exchange (ETDEWEB)

    Bednar, J [Research Institute of Endocrinology, Prague (Czechoslovakia)

    1980-03-20

    The application of a microchemical method for the estimation of thyroxine (T/sub 4/) and triiodothyronine (T/sub 3/) in blood serum for the simultaneous determination of both hormones in urine is described. The results were corrected for possible losses during the analytical procedure using known amounts of /sup 131/I-T/sub 4/ and /sup 131/I-T/sub 3/ added to the analyzed samples. The developed method is not convenient for diagnostic purposes on account of the fact that the total concentration of both hormones and not only the percentage of hormones unbound in the form of conjugates is estimated.

  8. Comparative characterization of molecular varieties of thyroxine-binding human globulin

    International Nuclear Information System (INIS)

    Ermolenko, M.N.; Sviridov, O.V.; Strel'chenok, O.A.

    1986-01-01

    Two molecular varieties of thyroxine-binding globulin (TBG) of human retroplacental blood, obtained as a result of fractionation of pure TBG on concanavalin A-Sepharose, were studied. It was shown that these varieties (TBG-1 and TBG-2) are immunologically identical; they have the same molecular weight and amino acid composition, exhibit the same affinity for thyroid hormones, and are indistinguishable in spectral characteristics. And yet, TBG-1 and TBG-2 have differences in charge, detectable in isoelectrofocusing, and a different monosaccharide composition. The existence of molecular varieties of TBG during pregnancy is apparently due to the peculiarities of the glycosylation of the polypeptide chain during TBG biosynthesis

  9. The Coxiella Burnetii type IVB secretion system (T4BSS) component DotA is released/secreted during infection of host cells and during in vitro growth in a T4BSS-dependent manner.

    Science.gov (United States)

    Luedtke, Brandon E; Mahapatra, Saugata; Lutter, Erika I; Shaw, Edward I

    2017-06-01

    Coxiella burnetii is a Gram-negative intracellular pathogen and is the causative agent of the zoonotic disease Q fever. To cause disease, C. burnetii requires a functional type IVB secretion system (T4BSS) to transfer effector proteins required for the establishment and maintenance of a membrane-bound parasitophorous vacuole (PV) and further modulation of host cell process. However, it is not clear how the T4BSS interacts with the PV membrane since neither a secretion pilus nor an extracellular pore forming apparatus has not been described. To address this, we used the acidified citrate cysteine medium (ACCM) along with cell culture infection and immunological techniques to identify the cellular and extracellular localization of T4BSS components. Interestingly, we found that DotA and IcmX were secreted/released in a T4BSS-dependent manner into the ACCM. Analysis of C. burnetii-infected cell lines revealed that DotA colocalized with the host cell marker CD63 (LAMP3) at the PV membrane. In the absence of bacterial protein synthesis, DotA also became depleted from the PV membrane. These data are the first to identify the release/secretion of C. burnetii T4BSS components during axenic growth and the interaction of a T4BSS component with the PV membrane during infection of host cells. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Laboratory data of serum triiodothyronine, thyroxine and thyrotrophin dosages for diagnosis of primary hypothyroidism

    International Nuclear Information System (INIS)

    Nicolau, W.; Abelin, N.M.A.; Villares, S.M.; Mattar, E.

    1984-01-01

    TSH dosages are studied in 5.598 patients during 31 months. TSH values equal or superior than 10 μlU/ml was chosen (360 samples). These ones, 193 presented T 3 and T 4 results changed, too. The several factors that could influence the normal peripheral levels of T 3 and T 4 in primary hypothyroidal patients and the factors that cause an eventual low correlation with TSH are discussed. (M.A.C.) [pt

  11. Early determination of the congenital hypothyroidism by means of the cuantification of STH and T4 by radioimmunoassay method

    International Nuclear Information System (INIS)

    De Penados, R.C.

    1986-11-01

    It was investigated the advantages and disadvantages and conditions of working for the diagnosis of the congenital hypothyroidism by RIA, and its future implementation. It was determined concentration of neonatal STH and neonatal T4 in whole blood of 517 new borns, obtained by capilar punction and recollected in filter paper. 261 samples were found with levels of T4 between normal limits and STH between 0 and 12.5 u U/ml correspond to a normal thyroid function. 29 samples with normal T4 and STH above 30 u U/ml, correspond to a possible primary hypothyroidism. 171 samples with normal T4 and STH between 12.5 and 30 u U/ml were found. (Author)

  12. Fast algorithms for coordinate processors in Galois field for multiplicity t = 4.5 and t > 5

    International Nuclear Information System (INIS)

    Nikityuk, N.M.

    1989-01-01

    Fast algorithms for solving the coordinate equations for special-purpose processors at multiplicity t = 4.5 and t > 5 are described. Block diagrams of coordinate processor for t 4 in Galois field GF(2 m ) is presented which is solved by a table method. Economical algorithms for solving the coordinate equations by serial methods at t > 5 are described. The algorithms and devices proposed could be applied when creating fast processors in high energy physics spectrometers. 9 refs.; 3 figs

  13. The mechanisms of action of E. coli endonuclease III and T4 UV endonuclease (endonuclease V) at AP sites.

    OpenAIRE

    Kim, J; Linn, S

    1988-01-01

    Treatment of DNA containing AP sites with either T4 UV endonuclease or with E. coli endonuclease III followed by a human class II AP endonuclease releases a putative beta-elimination product. This result suggests that both the T4 endonuclease and E. coli endonuclease III class I AP endonucleases catalyze phosphodiester bond cleavage via a lyase- rather than a hydrolase mechanism. Indeed, we have not detected a class I AP endonuclease which hydrolytically catalyzes phosphodiester bond cleavage...

  14. Serum thyroxine concentrations following fixed-dose radioactive iodine treatment in hyperthyroid cats: 62 cases (1986-1989)

    International Nuclear Information System (INIS)

    Meric, S.M.; Rubin, S.I.

    1990-01-01

    The medical records of 62 hyperthyroid cats treated with a fixed dose of 4 mCi of radioactive iodine (131I) were reviewed. In 60 cats, serum thyroxine concentrations were determined after treatment, allowing evaluation of treatment success. Eighty-four percent of the cats had normal serum thyroxine concentrations after treatment. Five of the 60 cats (8%) remained hyperthyroxinemic after treatment. Five cats (8%) were hypothyroxinemic when evaluated within 60 days of treatment. Three of these cats had normal serum thyroxine concentrations 6 months after treatment, and none had clinical signs of hypothyroidism. The administration of a fixed dose of 4 mCi of 131I was determined to be an effective treatment for feline hyperthyroidism

  15. Reduction and repopulation of recipient T4+ and T8+ T-lymphocytes in allogeneic bone marrow transplantation

    International Nuclear Information System (INIS)

    Gratama, J.W.; van den Bergh, R.L.; Naipal, A.; D'Amaro, J.; Zwaan, F.E.; Jansen, J.; de Gast, G.C.

    1986-01-01

    In eight recipients of allogeneic bone marrow grafts who had sex-mismatched donors, the reduction and subsequent repopulation of T4+ and T8+ T-lymphocytes of recipient origin were studied. The origin of the donor-recipient T4+ and T8+ T cells was studied using quinacrine staining of Y chromatin combined with T-cell typing for T4 and T8. Following chemoradiotherapy and bone marrow transplantation (BMT), T cells reached their nadir at a median of five (range 1-8) days after BMT. T8+ T cells decreased at a faster rate from the peripheral blood than T4+ T cells. The first T cells that appeared in the circulation at day 12 were predominantly T4+, and a large number of them were of recipient origin. Thereafter, they gradually decreased, and the numbers of T cells of donor origin increased. In the patients who had no or only minor complications, T4+ and T8+ T cells of donor origin repopulated the blood at similar rates. This pattern, however, was modified by severe graft-versus-host disease or by cytomegalovirus infection

  16. Relationship Between Circulating Thyroid-Stimulating Hormone, Free Thyroxine, and Free Triiodothyronine Concentrations and 9-Year Mortality in Euthyroid Elderly Adults.

    Science.gov (United States)

    Ceresini, Graziano; Marina, Michela; Lauretani, Fulvio; Maggio, Marcello; Bandinelli, Stefania; Ceda, Gian P; Ferrucci, Luigi

    2016-03-01

    To determine the association between plasma thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) levels and all-cause mortality in older adults who had levels of all three hormones in the normal range. Longitudinal. Community-based. Euthyroid Invecchiare in Chianti study participants aged 65 and older (N = 815). Plasma TSH, FT3, and FT4 levels were predictors, and 9-year all-cause mortality was the outcome. Cox proportional hazards models adjusted for confounders were used to examine the relationship between TSH, FT3, and FT4 quartiles and all-cause mortality over 9 years of follow-up. During follow-up (mean person-years 8,643.7, range 35.4-16,985.0), 181 deaths occurred (22.2%). Participants with TSH in the lowest quartile had higher mortality than the rest of the population. After adjusting for multiple confounders, participants with TSH in the lowest quartile (hazard ratio = 2.22, 95% confidence interval = 1.19-4.22) had significantly higher all-cause mortality than those with TSH in the highest quartile. Neither FT3 nor FT4 was associated with mortality. In elderly euthyroid subjects, normal-low TSH is an independent risk factor for all-cause mortality. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

  17. Regulation of vernal migration in Gambel's white-crowned sparrows: Role of thyroxine and triiodothyronine.

    Science.gov (United States)

    Pérez, Jonathan H; Furlow, J David; Wingfield, John C; Ramenofsky, Marilyn

    2016-08-01

    Appropriate timing of migratory behavior is critical for migrant species. For many temperate zone birds in the spring, lengthening photoperiod is the initial cue leading to morphological, physiological and behavior changes that are necessary for vernal migration and breeding. Strong evidence has emerged in recent years linking thyroid hormone signaling to the photoinduction of breeding in birds while more limited information suggest a potential role in the regulation of vernal migration in photoperiodic songbirds. Here we investigate the development and expression of the vernal migratory life history stage in captive Gambel's white-crowned sparrows (Zonotrichia leucophrys gambelii) in a hypothyroidic state, induced by chemical inhibition of thyroid hormone production. To explore possible variations in the effects of the two thyroid hormones, triiodothyronine and thyroxine, we subsequently performed a thyroid inhibition coupled with replacement therapy. We found that chemical inhibition of thyroid hormones resulted in complete abolishment of mass gain, fattening, and muscle hypertrophy associated with migratory preparation as well as resulting in failure to display nocturnal restlessness behavior. Replacement of thyroxine rescued all of these elements to near control levels while triiodothyronine replacement displayed partial or delayed rescue. Our findings support thyroid hormones as being necessary for the expression of changes in morphology and physiology associated with migration as well as migratory behavior itself. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Effects of Seasonal Changes, Age and Smoking on Haemostatic Factors and Thyroxine Level in Egyptian Men

    International Nuclear Information System (INIS)

    Kamal, T.H.; Bahgat, M. M.; Haggag, A. M.; Taha, M. E.

    2002-01-01

    ONE hundred and twenty male volunteers arranged into 6 equal groups participated in the present study to investigate the influence of age, smoking and season on clot formation, clot lysis and thyroxine hormone. Erythrocyte sedimentation rate, clotting time, platelet count, haemoglobin content, red blood cell count, haematocrit, total leukocytic count, fibrinogen, prothrombin time and concentration, partial thromboplastin time, factor V, VIII, plasminogen and thyroxine hormone were estimated in each group. The effect of age was studied by comparing young individuals (11-16 years) with adult non smokers (30-40 years) . Simultaneously adult non smokers were compared to adult smokers to evaluate the effect of smoking.Three groups: young , adult non smokers and adult smokers during winter were compared with their corresponding groups in summer to assess the season effect.The results revealed that most changes in the three groups were due to temperature variation and the young group had a better thermoregulation control than both adult groups .In non smoker adult group winter caused hypercoagulation with a concomitant increase in fibrinolytic activity as a protective mechanism against thrombus formation. Smoking caused disturbances in many coagulation factors and interaction between smoking and season is evident causing vascular disturbances. In summer smokers are more liable to bleeding, while in winter they are more liable to thrombus formation providing the other condition interfering with bleeding and thrombus formation are constant. There is relative hypothyroidism in smoker group only in summer season

  19. Evaluation and comparison of radio-, fluorescence, and enzyme-linked immunoassays for serum thyroxine

    International Nuclear Information System (INIS)

    Kaplan, L.A.; Gau, N.; Fearn, J.; Steain, E.A.; Chen, I.W.; Maxon, H.; Volle, C.

    1981-01-01

    We have compared three analytical systems for the measurement of serum thyroxine: enzyme-linked immunoassay (EIA), fluorescent immunoassay (FIA) and a radioimmunoassay (RIA). These were evaluated with respect to their precision, accuracy, analytical sensitivity and sample throughput. The RIA is more sensitive than the EIA (10 μg/L vs. 35 μg/L). Both systems have excellent precision (X=86 μg/L, C.V.sub(RIA)=C.V.sub(EIA)=4.6 percent). Both the EIA and RIA demonstrate good accuracy with recovery of between 97-98 percent of added thyroxine. The FIA has an apparent sensitiviity between that of the RIA and EIA (25 μg/L), but a precision consistently lower than the other two systems (C.V. =7.4 percent, X=86 μg/L). Patients' results by RIA compared well with those from EIA (r=0.91,P 0.05). Although not fully automated, the EIA performed on the Abbott ABA-100 analyzer has a sample throughput equal to the automated RIA system (Micromedic, Concept 4)

  20. Insulin and thyroxine effect on /sup 32/P incorporation in the phospholipids of chicken intestinal mucosa

    Energy Technology Data Exchange (ETDEWEB)

    Aleksandrov, S; Lazarov, J [Akademiya na Selskostopanskite Nauki, Sofia-Kostinbrod (Bulgaria). Inst. po Zhivotnovydstvo

    1977-01-01

    Trials were conducted with 56-day-old broiler chickens. The effect was followed up of insulin and alloxan as well as of L-thyroxine and 6-methylthiouracil on /sup 32/P incorporation in phospholipids of the duodenal mucosa. A segment of the duodenum was isolated and Na/sub 2/H/sup 32/PO/sub 4/ was introduced therein. The lipids were extracted from duodenal mucosa and the individual phospholipids were separated by means of thin layer chromatography on sillica gel-G. Radioactivity was determined of individual phospholipid fractions. Blood glucose level was studied in insulin and alloxan-treated chickens. The inference was drawn that insulin significantly enhances /sup 32/P incorporation in the phospholipids in broiler chicken duodenal mucosa. The drop in blood glucose in insulin-treated chickens is inversely proportional to /sup 32/ P inclusion in individual phospholipids of duodenal mucosa. L-thyroxine exerts positive effect in chickens concerning /sup 32/P incorporation in lecithin and lysolecithin, this effect being negative with respect to sphingomyelin, cephalin and cardiolipin. Thyroid gland inhibition by 6-methylthiouracil induces negligible decline in /sup 32/P inclusion.

  1. Oral T4-like phage cocktail application to healthy adult volunteers from Bangladesh

    International Nuclear Information System (INIS)

    Sarker, Shafiqul Alam; McCallin, Shawna; Barretto, Caroline; Berger, Bernard; Pittet, Anne-Cécile; Sultana, Shamima; Krause, Lutz; Huq, Sayeda; Bibiloni, Rodrigo; Bruttin, Anne; Reuteler, Gloria; Brüssow, Harald

    2012-01-01

    The genomic diversity of 99 T4-like coliphages was investigated by sequencing an equimolar mixture with Illumina technology and screening them against different databases for horizontal gene transfer and undesired genes. A 9-phage cocktail was given to 15 healthy adults from Bangladesh at a dose of 3×10 9 and 3×10 7 plaque-forming units and placebo respectively. Phages were detected in 64% of the stool samples when subjects were treated with higher titer phage, compared to 30% and 28% with lower-titer phage and placebo, respectively. No Escherichia coli was present in initial stool samples, and no amplification of phage was observed. One percent of the administered oral phage was recovered from the feces. No adverse events were observed by self-report, clinical examination, or from laboratory tests for liver, kidney, and hematology function. No impact of oral phage was seen on the fecal microbiota composition with respect to bacterial 16S rRNA from stool.

  2. Anisotropic deformation behavior of as-extruded 6063-T4 alloy under dynamic impact loading

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Tuo [State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082 (China); Li, Luoxing, E-mail: luoxing_li@yahoo.com [State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082 (China); Joint Center for Intelligent New Energy Vehicle, Tongji University, Shanghai 200092 (China); Liu, Xiao; Liu, Wenhui [Key Laboratory of High Temperature Wear Resistant Materials Preparation Technology of Hunan Province, Hunan University of Science and Technology, Xiangtan 411201 (China); Guo, Pengcheng; Tang, Xu [State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082 (China)

    2016-06-01

    The deformation behavior of 6063-T4 aluminum alloy bar was investigated by compression tests conducted at a wide strain rate range of 10{sup −4} to 9×10{sup 3} s{sup −1} with loading directions at 0°, 45° and 90° to the axis of the extruded bar. It is found that the flow stresses of 0° specimens are always the highest and those of the 45° specimens are the lowest at the same conditions. The flow stress exhibits obvious strain rate sensitivity (SRS), which differs from static to dynamic deformation. The Schmid factors (SFs) for each type of texture components were calculated. For the {112}<111> texture component, the max Schmid factors are 0.27, 0.49 and 0.41 for 0°, 45° and 90° specimens. For the {110}<111> texture component, they are 0.27, 0.43 and 0.41 for the three directions. The initial texture changes significantly with increasing strain, the strain rate has slight influence on the texture evolution. The transmission electron microscope (TEM) observations indicate that as the strain rate increases, the density of the dislocation increases and its distribution becomes more homogeneous. It is necessary to consider the anisotropic deformation behavior and microstructure evolution in material selection and structure design for the impact components.

  3. SIGNIFICANCE OF THYROID PROFILE (Serum T3, T4 & TSH IN INFERTILE WOMEN

    Directory of Open Access Journals (Sweden)

    Bindu Sharma

    2012-06-01

    Full Text Available Objective: To evaluate the relation of female infertility to thyroid dysfunction. Material & Methods: The present study was carried out in the department of Biochemistry in collaboration with the Gynae & Obst deptt., Subharti Medical College & Hospital Meerut. Serum T3, T4 and TSH estimation was done by Enzyme Linked Fluorescent Assay. Results: Serum T3 level in control group was 1.8 ± 0.64 nmol/L while it was 10.5 ± 0.5 nmol/L in hyperthyroid (p value 0.05, i.e., not significant. Serum TSH in control group was 3.5 ± 1.71 mIU/L, while it was 0.14 ± 0.01 mIU/L (p value <0.001, i.e., highly significant in hyperthyroidism, 8.4 ± 1.06 mIU/L in hypothyroidism (p value <0.001, i.e., highly significant. Out of 65 patients of study group thyroid dysfunction was associated with 25 (38.5% infertile women. 23 (35.4% women had hypothyroidism, 2 (3.1% women had hyperthyroidism and 40 women (61.5% were with euthyroid state, while in control group all the 25 women had euthyroid profile. Conclusions: Every infertile woman with ovulatory dysfunction should also investigated thyroid profile along with other investigations, to open better prospects of conception for such desperate infertile women.

  4. Partial replicas of uv-irradiated bacteriophage T4 genomes and their role in multiplicity reactivation

    International Nuclear Information System (INIS)

    Rayssiguier, C.; Kozinski, A.W.; Doermann, A.H.

    1980-01-01

    A physicochemical study was made of the replication and transmission of uv-irradiated T4 genomes. The data presented in this paper justify the following conclusions. (i) For both low and high multiplicity of infection there was abundant replication from uv-irradiated parental templates. It exceeded by far the efficiency predicted by the hypothesis that a single lethal hit completely prevents replication of the killed phage DNA: i.e., some dead phage particles must replicate parts of their DNA. (ii) Replication of the uv-irradiated DNA was repetitive as shown by density reversal experiments. (iii) Newly synthesized progeny DNA originating from uv-irradiated templates appeared as significantly shorter segments of the genomes than progeny DNA produced from non-uv-irradiated templates. A good correlation existed between the number of uv hits and the number of random cuts that would be needed to reduce replication fragments to the length observed. (iv) The contribution of uv-irradiated parental DNA among progeny phage in multiplicity reactivation was disposed in shorter subunits than was the DNA from unirradiated parental phage. It is important to emphasize that it was mainly in the form of replicative hybrid. These conclusions appear to justify excluding interparental recombination as a prerequisite for multiplicity reactivation. They lead directly to some form of partial replica hypothesis for multiplicity reactivation

  5. Molecular identification of t4 and t5 genotypes in isolates from acanthamoeba keratitis patients.

    Science.gov (United States)

    Ledee, D R; Iovieno, A; Miller, D; Mandal, N; Diaz, M; Fell, J; Fini, M E; Alfonso, E C

    2009-05-01

    Acanthamoeba keratitis (AK) is a rare but sight-threatening ocular infection. Outbreaks have been associated with contaminated water and contact lens wear. The epidemiology and pathology may be associated with unique genotypes. We determined the Rns genotype for 37 clinical isolates from 23 patients presenting at the University of Miami Bascom Palmer Eye Institute with confirmed AK infections in 2006 to 2008. The genus-specific ASA.S1 amplicon allowed for rapid genotyping of the nonaxenic cultures. Of the 37 isolates, 36 were of the T4 genotype. Within this group, 13 unique diagnostic fragment 3 sequences were identified, 3 of which were not in GenBank. The 37th isolate was a T5, the first in the United States and second worldwide to be found in AK. For five patients with isolates from the cornea and contact lens/case, identical sequences within each patient cluster were observed, confirming the link between contact lens contamination and AK infection. Genotyping is an important tool in the epidemiological study of AK. In this study, it allowed for the detection of new strains and provided an etiological link between source and infection. Additionally, it can allow for accurate categorizing of physiological differences, such as strain virulence, between isolates and clades.

  6. Oral T4-like phage cocktail application to healthy adult volunteers from Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Shafiqul Alam, E-mail: sasarker@icddrb.org [International Centre for Diarrhoeal Diseases Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sharani, Mohakhali, Dhaka 1212 (Bangladesh); McCallin, Shawna; Barretto, Caroline [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Berger, Bernard, E-mail: bernard.berger@rdls.nestle.com [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Pittet, Anne-Cecile [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Sultana, Shamima, E-mail: shamima@icddrb.org [International Centre for Diarrhoeal Diseases Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sharani, Mohakhali, Dhaka 1212 (Bangladesh); Krause, Lutz, E-mail: ltz.krause@gmail.com [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Huq, Sayeda, E-mail: sayeeda@mail.icddrb.org [International Centre for Diarrhoeal Diseases Research, Bangladesh (icddr,b), 68 Shaheed Tajuddin Ahmed Sharani, Mohakhali, Dhaka 1212 (Bangladesh); Bibiloni, Rodrigo, E-mail: Rodrigo.Bibiloni@agresearch.co.nz [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Bruttin, Anne, E-mail: anne.bruttin@rdls.nestle.com [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Reuteler, Gloria, E-mail: gloria.reuteler@rdls.nestle.com [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland); Bruessow, Harald, E-mail: harald.bruessow@rdls.nestle.com [Nestle Research Centre, Nestec Ltd., Vers-chez-les-Blanc, CH-1000 Lausanne 26 (Switzerland)

    2012-12-20

    The genomic diversity of 99 T4-like coliphages was investigated by sequencing an equimolar mixture with Illumina technology and screening them against different databases for horizontal gene transfer and undesired genes. A 9-phage cocktail was given to 15 healthy adults from Bangladesh at a dose of 3 Multiplication-Sign 10{sup 9} and 3 Multiplication-Sign 10{sup 7} plaque-forming units and placebo respectively. Phages were detected in 64% of the stool samples when subjects were treated with higher titer phage, compared to 30% and 28% with lower-titer phage and placebo, respectively. No Escherichia coli was present in initial stool samples, and no amplification of phage was observed. One percent of the administered oral phage was recovered from the feces. No adverse events were observed by self-report, clinical examination, or from laboratory tests for liver, kidney, and hematology function. No impact of oral phage was seen on the fecal microbiota composition with respect to bacterial 16S rRNA from stool.

  7. Pourquoi le Grundgedanke (T. 4.0312 de Wittgenstein est si “Fondamental”?

    Directory of Open Access Journals (Sweden)

    André Leclerc

    1998-12-01

    Full Text Available La pensée fondamentale de Wittgenstein affirme que les constantes logiques ne représentent pas, ne fonctionnent pas sémantiquement comme des noms. En apparence triviale, cette pensée, nous le montrerons, à des ramifications étonnantes dans la philosophie du premier Wittgenstein, en particulier en ce qui concerne sa conception de la logique. Notre but est d'interpréter l'aphorisme en question (T. 4.0312 en montrant comment il se rapporte aux thèses et théories les plus importantes du Tractatus, et comment il permet de les faire tenir ensemble d'une façon cohérente, justifiant par là son caractère "fondamental". Nous tentons également d'apporter une réponse aux questions suivantes : les propositions complexes sont-elles encore - comme les propositions atomiques - des "images" de la réalité ? et quelle est cette "logique des faits" dont parle Wittgenstein dans l'aphorisme sous examen ?

  8. Thyroxine binding to serum thyronine-binding globulin in thyroidectomized adult and normal neonatal rats

    International Nuclear Information System (INIS)

    Young, R.A.; Meyers, B.; Alex, S.; Fang, S.L.; Braverman, L.E.

    1988-01-01

    The amount of tracer [125I]T4 bound to serum thyronine-binding globulin (TBG) was measured by polyacrylamide gel electrophoresis in adult thyroidectomized (TX) rats and normal 1-day to 4-week-old rat puts. Thyroidectomy was associated with the appearance of significant amounts of [125I]T4 binding to serum TBG in lean rats, but not in obese Zucker rats. Treatment of the TX rats in vivo with replacement doses of T4 prevented this increase in TBG binding, but enrichment of serum from TX rats with T4 did not. Significant amounts of tracer [125I]T4 binding to TBG was present in serum from 1- to 3-week-old normal rat pups, but not in 1-day- or 4-week-old pups. There were significantly higher levels of TBG binding of [125I]T4 in serum from 2-week-old rat pups raised in litters of 16 pups compared to those raised in litters of 4 pups. All manipulations that result in the appearance of TBG in rat serum also result in either weight loss or a slowing in the rate of growth, suggesting that the appearance of TBG in rat serum has a nutritional component. This possibility is further supported by the observations that increases in TBG binding of [125I]T4 are not found in obese Zucker rats fed a low protein-high carbohydrate diet for 14 days or fasted for 7 days, or after thyroidectomy, perhaps owing to the large stores of fuel in the obese rat

  9. Median nerve conduction velocity and central conduction time measured with somatosensory evoked potentials in thyroxine-treated infants with Down syndrome

    NARCIS (Netherlands)

    van Trotsenburg, A. S. Paul; Smit, Bert J.; Koelman, Johannes H. T. M.; Dekker-van der Sloot, Marijke; Ridder, Jeannette C. D.; Tijssen, Jan G. P.; de Vijlder, Jan J. M.; Vulsma, Thomas

    2006-01-01

    OBJECTIVE: The aim of this study was to determine whether thyroxine treatment would improve nerve conduction in infants with Down syndrome. METHODS: A single-center, nationwide, randomized, double-blind, clinical trial was performed. Neonates with Down syndrome were assigned randomly to thyroxine (N

  10. [The effect of synchronization on estrus and pregnancy in sheep and on levels of thyroxine, triiodothyronine, 17 beta-estradiol, progesterone and cholesterol].

    Science.gov (United States)

    Bekeová, E; Krajnicáková, M; Hendrichovský, V; Maracek, I

    1991-07-01

    Knowledge of pathogenesis of sexual dysfunctions at altered thyroid activity is limited by the knowledge of multiple and ubiquitous action of its hormones throughout the organism. One of the possibilities of modulatory influence of thyroid hormones on sexual functions can be realized through the participation of thyroxine and triiodothyronine in the synthesis and metabolism of primary substrate of steroid synthesis--cholesterol. The presented work is aimed at the study of simultaneous dynamic changes of concentrations of thyroxine (T4), triiodothyronine (T3), 17 beta-estradiol (E2), progesterone (P4) and cholesterol (Chol) during synchronization of the rutting period and gravidity at parallel correlative evaluation of mutual relations of the followed parameters in ten Merino sheep in the seasonal period. Synchronization was achieved by chlorsuperlutin (Agelin--vaginal swabs, Spofa; 20 mg of chlorsuperlutin/swab) and PMSG (500 I. U./animal). Blood was sampled by means of a jugular vein puncture at the time of swab insertion (-13th day) and after three (-10th day) and seven (-7th day) following days, at the removal of swabs and application of PMSG (-3rd day), on the day of insemination (zero day), on the 7th, 14th and 17th day and in the middle of the 2nd, 3rd, 4th and 5th month of gravidity. In the phase of oestrus synchronization a significant increase of E2 concentrations on days -7 and -3 of the experiment (0.47 +/- 0.079 and 0.542 +/- 0.177 nmol.l-1 of serum, P less than 0.001; P less than 0.001) was observed compared to the E2 values on day -13 (0.084 +/- 0.036 nmol.l-1 of serum). Parallel to these observations, marked intermittent changes of T4 (Tab. I, Graph 1) were recorded with the lowest values of this parameter observed on days -10 (41.75 +/- 20.23, P less than 0.05) and -3 (50.22 +/- 18.77, P less than 0.05) and the highest on day -7 (96.77 +/- 17.51 nmol.l-1, P less than 0.01) and day zero (85.40 +/- 19.59 nmol.l-1 of serum, P less than 0.05) in

  11. Phage T4 SegB protein is a homing endonuclease required for the preferred inheritance of T4 tRNA gene region occurring in co-infection with a related phage.

    Science.gov (United States)

    Brok-Volchanskaya, Vera S; Kadyrov, Farid A; Sivogrivov, Dmitry E; Kolosov, Peter M; Sokolov, Andrey S; Shlyapnikov, Michael G; Kryukov, Valentine M; Granovsky, Igor E

    2008-04-01

    Homing endonucleases initiate nonreciprocal transfer of DNA segments containing their own genes and the flanking sequences by cleaving the recipient DNA. Bacteriophage T4 segB gene, which is located in a cluster of tRNA genes, encodes a protein of unknown function, homologous to homing endonucleases of the GIY-YIG family. We demonstrate that SegB protein is a site-specific endonuclease, which produces mostly 3' 2-nt protruding ends at its DNA cleavage site. Analysis of SegB cleavage sites suggests that SegB recognizes a 27-bp sequence. It contains 11-bp conserved sequence, which corresponds to a conserved motif of tRNA TpsiC stem-loop, whereas the remainder of the recognition site is rather degenerate. T4-related phages T2L, RB1 and RB3 contain tRNA gene regions that are homologous to that of phage T4 but lack segB gene and several tRNA genes. In co-infections of phages T4 and T2L, segB gene is inherited with nearly 100% of efficiency. The preferred inheritance depends absolutely on the segB gene integrity and is accompanied by the loss of the T2L tRNA gene region markers. We suggest that SegB is a homing endonuclease that functions to ensure spreading of its own gene and the surrounding tRNA genes among T4-related phages.

  12. T4 bacteriophage conjugated magnetic particles for E. coli capturing: Influence of bacteriophage loading, temperature and tryptone.

    Science.gov (United States)

    Liana, Ayu Ekajayanthi; Marquis, Christopher P; Gunawan, Cindy; Gooding, J Justin; Amal, Rose

    2017-03-01

    This work demonstrates the use of bacteriophage conjugated magnetic particles (Fe 3 O 4 ) for the rapid capturing and isolation of Escherichia coli. The investigation of T4 bacteriophage adsorption to silane functionalised Fe 3 O 4 with amine (NH 2 ), carboxylic (COOH) and methyl (CH 3 ) surface functional groups reveals the domination of net electrostatic and hydrophobic interactions in governing bacteriophage adsorption. The bare Fe 3 O 4 and Fe 3 O 4 -NH 2 with high T4 loading captured 3-fold more E. coli (∼70% capturing efficiency) compared to the low loading T4 on Fe 3 O 4 -COOH, suggesting the significance of T4 loading in E. coli capturing efficiency. Importantly, it is further revealed that E. coli capture is highly dependent on the incubation temperature and the presence of tryptone in the media. Effective E. coli capturing only occurs at 37°C in tryptone-containing media with the absence of either conditions resulted in poor bacteria capture. The incubation temperature dictates the capturing ability of Fe 3 O 4 /T4, whereby T4 and E. coli need to establish an irreversible binding that occurred at 37°C. The presence of tryptophan-rich tryptone in the suspending media was also critical, as shown by a 3-fold increase in E. coli capture efficiency of Fe 3 O 4 /T4 in tryptone-containing media compared to that in tryptone-free media. This highlights for the first time that successful bacteria capturing requires not only an optimum tailoring of the particle's surface physicochemical properties for favourable bacteriophage loading, but also an in-depth understanding of how factors, such as temperature and solution chemistry influence the subsequent bacteriophage-bacteria interactions. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Plasma proteome and metabolome characterization of an experimental human thyrotoxicosis model

    DEFF Research Database (Denmark)

    Pietzner, Maik; Engelmann, Beatrice; Kacprowski, Tim

    2017-01-01

    BACKGROUND: Determinations of thyrotropin (TSH) and free thyroxine (FT4) represent the gold standard in evaluation of thyroid function. To screen for novel peripheral biomarkers of thyroid function and to characterize FT4-associated physiological signatures in human plasma we used an untargeted O...

  14. A genome-wide association study of thyroid stimulating hormone and free thyroxine in Danish children and adolescents

    DEFF Research Database (Denmark)

    Nielsen, Tenna Ruest Haarmark; Appel, Emil Vincent Rosenbaum; Svendstrup, Mathilde

    2017-01-01

    BackgroundHypothyroidism is associated with obesity, and thyroid hormones are involved in the regulation of body composition, including fat mass. Genome-wide association studies (GWAS) in adults have identified 19 and 6 loci associated with plasma concentrations of thyroid stimulating hormone (TSH...... data with fasting plasma concentrations of TSH and fT4 from a population-based sample of Danish children, adolescents, and young adults, and a group of children, adolescents, and young adults with overweight and obesity were performed (N = 1,764, mean age = 12.0 years [range 2.5-24.7]). Replication...... associated with TSH in adults were confirmed in this study population (PDE10A (rs2983511: beta = 0.112SD, p = 4.8.10(-16)), FOXE1 (rs7847663: beta = 0.223SD, p = 1.5 . 10(-20)), NR3C2 (rs9968300: beta = 0.194SD), p = 2.4 . 10(-11)), VEGFA (rs2396083: beta = 0.088SD, p = 2.2 . 10(-10))). Effect sizes...

  15. Activity of thyroxine 5' deiodinase in brown fat of lean and obese zucker rats

    International Nuclear Information System (INIS)

    Wu, S.Y.; Fisher, D.A.; Stern, J.S.; Glick, Z.

    1986-01-01

    This study examines the possibility that the reduced brown adipose tissue (BAT) thermogenesis in the Zucker obese rat may result from a limited capacity for conversion of T 4 to T 3 in BAT, through activity of T 4 5' deiodinase. Eighteen lean (Fa/.) and 18 age matched obese (fa/fa), about 16 weeks old, were each divided into 3 groups (n=6 per group). Group 1 and 2 were fed Purina Rat Chow and a cafeteria diet respectively for 21 days, and maintained at 22 0 C+/-2. Group 3 was fed rat chow and maintained at 8 0 C+/-1 for 7 days. Activity of T 4 5'deiodinase was determined in vitro. T 3 was measured by a radioimmunoassay. The rate of T 4 to T 3 conversion was similar in the lean and the obese rats maintained at room temperature, whether fed rat chow or a cafeteria diet (about 40 to 50 pmol T 3 /scapular BAT depot, per hour). However, lean rats exposed to the cold displayed about a 5 fold increase in T 4 5' deiodinase activity (p 3 may account for the reduced tolerance of obese animals to cold, but it does not account for their reduced diet induced BAT thermogenesis

  16. Molecular interactions and residues involved in force generation in the T4 viral DNA packaging motor.

    Science.gov (United States)

    Migliori, Amy D; Smith, Douglas E; Arya, Gaurav

    2014-12-12

    Many viruses utilize molecular motors to package their genomes into preformed capsids. A striking feature of these motors is their ability to generate large forces to drive DNA translocation against entropic, electrostatic, and bending forces resisting DNA confinement. A model based on recently resolved structures of the bacteriophage T4 motor protein gp17 suggests that this motor generates large forces by undergoing a conformational change from an extended to a compact state. This transition is proposed to be driven by electrostatic interactions between complementarily charged residues across the interface between the N- and C-terminal domains of gp17. Here we use atomistic molecular dynamics simulations to investigate in detail the molecular interactions and residues involved in such a compaction transition of gp17. We find that although electrostatic interactions between charged residues contribute significantly to the overall free energy change of compaction, interactions mediated by the uncharged residues are equally if not more important. We identify five charged residues and six uncharged residues at the interface that play a dominant role in the compaction transition and also reveal salt bridging, van der Waals, and solvent hydrogen-bonding interactions mediated by these residues in stabilizing the compact form of gp17. The formation of a salt bridge between Glu309 and Arg494 is found to be particularly crucial, consistent with experiments showing complete abrogation in packaging upon Glu309Lys mutation. The computed contributions of several other residues are also found to correlate well with single-molecule measurements of impairments in DNA translocation activity caused by site-directed mutations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Tools-4-Metatool (T4M): online suite of web-tools to process stoichiometric network analysis data from Metatool.

    Science.gov (United States)

    Xavier, Daniela; Vázquez, Sara; Higuera, Clara; Morán, Federico; Montero, Francisco

    2011-08-01

    Tools-4-Metatool (T4M) is a suite of web-tools, implemented in PERL, which analyses, parses, and manipulates files related to Metatool. Its main goal is to assist the work with Metatool. T4M has two major sets of tools: Analysis and Compare. Analysis visualizes the results of Metatool (convex basis, elementary flux modes, and enzyme subsets) and facilitates the study of metabolic networks. It is composed of five tools: MDigraph, MetaMatrix, CBGraph, EMGraph, and SortEM. Compare was developed to compare different Metatool results from different networks. This set consists of: Compara and ComparaSub which compare network subsets providing outputs in different formats and ComparaEM that seeks for identical elementary modes in two metabolic networks. The suite T4M also includes one script that generates Metatool input: CBasis2Metatool, based on a Metatool output file that is filtered by a list of convex basis' metabolites. Finally, the utility CheckMIn checks the consistency of the Metatool input file. T4M is available at http://solea.quim.ucm.es/t4m. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  18. Hippocampal Neurometabolite Changes in Hypothyroidism: An In Vivo (1) H Magnetic Resonance Spectroscopy Study Before and After Thyroxine Treatment.

    Science.gov (United States)

    Singh, S; Rana, P; Kumar, P; Shankar, L R; Khushu, S

    2016-09-01

    The hippocampus is a thyroid hormone receptor-rich region of the brain. A change in thyroid hormone levels may be responsible for an alteration in hippocampal-associated function, such as learning, memory and attention. Neuroimaging studies have shown functional and structural changes in the hippocampus as a result of hypothyroidism. However, the underlying process responsible for this dysfunction remains unclear. Therefore, the present study aimed to investigate the metabolic changes in the brain of adult hypothyroid patients during pre- and post-thyroxine treatment using in vivo proton magnetic resonance spectroscopy ((1) H MRS). (1) H MRS was performed in both healthy control subjects (n = 15) and hypothyroid patients (n = 15) (before and after thyroxine treatment). The relative ratios of the neurometabolites were calculated using the linear combination model (LCModel). Our results revealed a significant decrease of glutamate (Glu) (P = 0.045) and myo-inositol (mI) (P = 0.002) levels in the hippocampus of hypothyroid patients compared to controls. No significant changes in metabolite ratios were observed in the hypothyroid patients after thyroxine treatment. The findings of the present study reveal decreased Glu/tCr and mI/tCr ratios in the hippocampus of hypothyroid patients and these metabolite alterations persisted even after the patients became clinically euthyroid subsequent to thyroxine treatment. © 2016 British Society for Neuroendocrinology.

  19. Baseline levels and trimestral variation of triiodothyronine and thyroxine and their association with mortality in maintenance hemodialysis patients.

    Science.gov (United States)

    Meuwese, Christiaan L; Dekker, Friedo W; Lindholm, Bengt; Qureshi, Abdul R; Heimburger, Olof; Barany, Peter; Stenvinkel, Peter; Carrero, Juan J

    2012-01-01

    Conflicting evidence exists with regard to the association of thyroid hormones and mortality in dialysis patients. This study assesses the association between basal and trimestral variation of thyroid stimulating hormone, triiodothyronine, and thyroxine and mortality. In 210 prevalent hemodialysis patients, serum triiodothyronine, thyroxine, thyroid stimulating hormone, and interleukin-6 were measured 3 months apart. Cardiovascular and non-cardiovascular deaths were registered during follow-up. Based on fluctuations along tertiles of distribution, four trimestral patterns were defined for each thyroid hormone: persistently low, decrease, increase, and persistently high. The association of baseline levels and trimestral variation with mortality was investigated with Kaplan-Meier curves and Cox proportional hazard models. During follow-up, 103 deaths occurred. Thyroid stimulating hormone levels did not associate with mortality. Patients with relatively low basal triiodothyronine concentrations had higher hazards of dying than patients with high levels. Longitudinally, patients with persistently low levels of triiodothyronine during the 3-month period had higher mortality hazards than those having persistently high levels. These associations were mainly attributable to cardiovascular-related mortality. The association between thyroxine and mortality was not altered after adjustment for triiodothyronine. Hemodialysis patients with reduced triiodothyronine or thyroxine levels bear an increased mortality risk, especially due to cardiovascular causes. This was true when considering both baseline measurements and trimestral variation patterns. Our longitudinal design adds observational evidence supporting the hypothesis that the link may underlie a causal effect.

  20. Bacteriophage T4 Nanoparticles as Materials in Sensor Applications: Variables That Influence Their Organization and Assembly on Surfaces

    Directory of Open Access Journals (Sweden)

    Jinny L. Liu

    2009-08-01

    Full Text Available Bacteriophage T4 nanoparticles possess characteristics that make them ideal candidates as materials for sensors, particularly as sensor probes. Their surface can be modified, either through genetic engineering or direct chemical conjugation to display functional moieties such as antibodies or other proteins to recognize a specific target. However, in order for T4 nanoparticles to be utilized as a sensor probe, it is necessary to understand and control the variables that determine their assembly and organization on a surface. The aim of this work is to discuss some of variables that we have identified as influencing the behavior of T4 nanoparticles on surfaces. The effect of pH, ionic strength, substrate characteristics, nanoparticle concentration and charge was addressed qualitatively using atomic force microscopy (AFM.

  1. T cell antigen receptor expression by subsets of Ly-2-L3T4- (CD8-CD4-) thymocytes

    DEFF Research Database (Denmark)

    Wilson, A; Ewing, T; Owens, T

    1988-01-01

    . No positive cells were detected among Ly-2-L3T4- thymocytes from V beta 8-negative SJL mice. In contrast to the adult thymus, Ly-2-L3T4- cells from embryonic CBA thymus lacked F23.1-positive cells. Subsets of adult CBA Ly-2-L3T4- thymocytes were separated to determine which expressed V beta 8. The major...... B2A2-M1/69- and Pgp-1+ all included strongly F23.1-positive cells. A minor subset, negative for most markers except Pgp-1 and presumed on the basis of this phenotype and some reconstitution studies to include the earliest intrathymic precursors, contained 28% F23.1-positive cells. However, no F.23...

  2. Enhancement of ultraviolet-DNA repair in denV gene transfectants and T4 endonuclease V-liposome recipients

    International Nuclear Information System (INIS)

    Kibitel, J.T.; Yee, V.; Yarosh, D.B.

    1991-01-01

    The phage T4 denV gene, coding for the pyrimidine-dimer specific T4 endonuclease V, was transfected into human repair-proficient fibroblasts, repair-deficient xeroderma pigmentosum fibroblasts, and wild type CHO hamster cells. Transfectants maintained denV DNA and expressed denV mRNA. Purified T4 endonuclease V encapsulated in liposomes was also used to treat repair-proficient and -deficient human cells. The denV transfected clones and liposome-treated cells showed increased unscheduled DNA synthesis and enhanced removal of pyrimidine dimers compared to controls. Both denV gene transfection and endonuclease V liposome treatment enhanced post-UV survival in xeroderma pigmentosum cells but had no effect on survival in repair-proficient human or hamster cells. The results demonstrate that an exogenous DNA repair enzyme can correct the DNA repair defect in xeroderma pigmentosum cells and enhance DNA repair in normal cells. (author)

  3. Disparate effects of heparin on free thyroxine measured by two different radioimmunoassays

    International Nuclear Information System (INIS)

    McDougall, I.R.; Bayer, M.F.; Nierenberg, D.; Lewis, S.J.

    1983-01-01

    Heparin causes a rise in free thyroxine (FT4) measured by equilibrium dialysis (E.D.). With the introduction of at least 4 commercial radioimmunoassays (RIA) for FT4, FT4 measurements have become accepted as one of the best routine thyroid function tests. Investigators have indicated that FT4 levels determined by RIA may be of particular value in patients hospitalized for various severe nonthyroidal illnesses in whom conventional thyroid function tests tend to be abnormal. However, very little information is as yet available on possible effects of various drugs on FT4 levels measured by these new methods. A study was undertaken to evaluate the effect of heparin on FT4 measured by 2 different RIA procedures: RIA-I, GammaCoat FT4 by clinical Assays and RIA-II, Amerlex FT4 by Amersham

  4. Free thyroxine in needle washout after fine needle aspiration biopsy of toxic thyroid nodules.

    Science.gov (United States)

    Raikov, Nikolai; Nonchev, Boyan; Chaushev, Borislav; Vjagova, Diyana; Todorov, Svetoslav; Bocheva, Yana; Malceva, Daniela; Vicheva, Snejinka; Raikova, Asyia; Argatska, Antoaneta; Raikov, Miroslav

    2016-01-01

    The main diagnostic tool for toxic adenomas (TA) is radionuclide imaging indicated in patients with evidence of thyroid nodules in combination with thyrotoxic syndrome. Thyroid ultrasound and fine-needle aspiration biopsy (FNAB) are widely used for the valuation of thyroid masses. There is no literature data concerning the utility of FNAB and related tests for the diagnosis of hyperfunctioning thyroid nodules. The purpose of this study is to determine the levels of free thyroxine (FT4) in the needle washout after FNAB of hot thyroid nodules. The results of our study show that the FT4 levels in needle washout from TA were significantly higher than the surrounding parenchyma and correlated with the hormonal changes in patients with thyroid hyperfunctioning nodules. Further studies on a large number of patients are needed to refine the diagnostic value of this method and evaluate its importance in quantitative risk assessment of thyroid autonomy.

  5. Actions of a proline analogue, L-thiazolidine-4-carboxylic acid (T4C, on Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    Anahí Magdaleno

    Full Text Available It is well established that L-proline has several roles in the biology of trypanosomatids. In Trypanosoma cruzi, the etiological agent of Chagas' disease, this amino acid is involved in energy metabolism, differentiation processes and resistance to osmotic stress. In this study, we analyzed the effects of interfering with L-proline metabolism on the viability and on other aspects of the T. cruzi life cycle using the proline analogue L- thiazolidine-4-carboxylic acid (T4C. The growth of epimastigotes was evaluated using different concentrations of T4C in standard culture conditions and at high temperature or acidic pH. We also evaluated possible interactions of this analogue with stress conditions such as those produced by nutrient starvation and oxidative stress. T4C showed a dose-response effect on epimastigote growth (IC(50 = 0.89+/-0.02 mM at 28 degrees C, and the inhibitory effect of this analogue was synergistic (p<0.05 with temperature (0.54+/-0.01 mM at 37 degrees C. T4C significantly diminished parasite survival (p<0.05 in combination with nutrient starvation and oxidative stress conditions. Pre-incubation of the parasites with L-proline resulted in a protective effect against oxidative stress, but this was not seen in the presence of the drug. Finally, the trypomastigote bursting from infected mammalian cells was evaluated and found to be inhibited by up to 56% when cells were treated with non-toxic concentrations of T4C (between 1 and 10 mM. All these data together suggest that T4C could be an interesting therapeutic drug if combined with others that affect, for example, oxidative stress. The data also support the participation of proline metabolism in the resistance to oxidative stress.

  6. Increased thyroidal T4 to T3 conversion in autonomously functioning thyroid adenoma: from euthyroidism to thyrotoxicosis.

    LENUS (Irish Health Repository)

    Solter, M

    2012-01-31

    AIM: The aim was to investigate whether the intrathyroid conversion of T4 to T3 in autonomously functioning thyroid adenoma (AFTA) tissue could influence serum T3 levels and suppression of TSH, especially in patients with borderline thyroid function. PATIENTS AND METHODS: In ten patients with AFTA, thyroidal conversion of T4 to T3 was investigated in nodular and paranodular, TSH-suppressed tissue. All patients had normal serum T4 and suppressed TSH. Serum T3 was normal in six, and borderline or slightly increased in four. AFTA and paranodular tissues were surgically removed and frozen at -70 degrees C, then homogenized in a glass homogenizer, centrifuged at 100,000xg, and particulate fraction collected as a pellet. Analysis mixture consisted of thyroid enzyme suspension in 50 mumol\\/L TRIS buffer with 5 mumol DTT and 200 muL 1.3 mumol T4. Incubation was performed at 37 degrees C and the generation of T3 measured after 5, 10, 20 and 40 minutes respectively. RESULTS: T3 production (pmol\\/mg protein) was significantly higher in AFTA than in paranodular tissues (8.8 1.2\\/Mean +\\/- SE\\/vs. 1.8 +\\/- 0.2; p<0.01), and excessively high (9.8, 14.1, 14.2 and 15.0) in four patients with borderline or slightly supranormal serum T3. A significant correlation was found between serum T3 concentrations and T3 generation (T4 conversion) in AFTA tissues. CONCLUSION: Results suggest that increased thyroidal T4 to T3 conversion in AFTA tissue could be involved in an increased delivery of T3, increased serum T3 and suppressed serum TSH, particularly in patients with the disease evolving from euthyroid to an early hyperthyroid phase.

  7. Intervalos de referencia para concentraciones séricas de T3 y T4. Estudio preliminar

    Directory of Open Access Journals (Sweden)

    Cecilia Miranda Pantoja

    2013-12-01

    Full Text Available Fundamento: la determinación cuantitativa de las hormonas tiroideas T3 y T4 reviste gran importancia en el diagnóstico y la evaluación del hipertiroidismo, en especial del hipertiroidismo aislado causado por T3.Objetivo: establecer los intervalos de referencia de T3 y T4 en el laboratorio de medicina nuclear del Hospital General Universitario Dr. Gustavo Aldereguía Lima de Cienfuegos. Métodos: estudio descriptivo y prospectivo realizado mediante el método de radioinmunoanálisis, competencia que se establece entre la T3 y T4 sin marcar, y la marcada por un número limitado de los sitios de unión del anticuerpo específico. Al hacer reaccionar una cantidad fija de trazador y anticuerpo con diferentes cantidades del ligando sin marcar, la cantidad de trazador unido por el anticuerpo será inversamente proporcional a la concentración del ligando sin marcar. Resultados: los valores obtenidos se describen según una distribución gaussiana (media aritmética = 117, desviación estándar =31 para T4; media aritmética = 2,64, desviación estándar = 0,64 para T3, comprobado mediante un test de Chi cuadrado. Los rangos de valores normales obtenidos fueron de de 55 – 178 nmol/L y 1,4 – 3,9 nmol/L para T4 y T3 respectivamente. Conclusiones: los intervalos de referencia obtenidos resultaron más amplios que los propuestos por el productor, sobre todo en el caso de T4.

  8. Effect of magnesium sulfate and thyroxine on inflammatory markers in a rat model of hypothyroidism.

    Science.gov (United States)

    Abbas, Amr M; Sakr, Hussein F

    2016-04-01

    Inflammation is a major risk factor for cardiovascular complications. Magnesium sulfate (MgSO4) has anti-inflammatory actions. Therefore we investigated the effects of levothyroxine and MgSO4 on inflammatory markers as C-reactive protein (CRP), interleukin-6, tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) in hypothyroid rats. Sixty male rats were divided into 6 groups; normal, normal + MgSO4, hypothyroidism, hypothyroidism + levothyroxine, hypothyroidism + MgSO4, and hypothyroidism + levothyroxine + MgSO4. Thyroxine, triiodothyronine, and thyroid-stimulating hormone (TSH), CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1 were measured in all rats. Hypothyroidism significantly increased TSH, CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1 and decreased triiodothronine and thyroxine. Treatment of hypothyroid rats with levothyroxine or MgSO4 significantly decreased CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1. Combined therapy of hypothyroid rats with levothyroxine and MgSO4 significantly decreased CRP, interleukin-6, TNF-α, ICAM-1, and VCAM-1 compared with hypothyroid rats either untreated or treated with levothyroxine or MgSO4. This study demonstrates that hypothyroid rats have chronic low grade inflammation, which may account for increased risk of cardiovascular diseases. Combined levothyroxine and MgSO4 is better than levothyroxine or MgSO4 alone in alleviating the chronic low grade inflammatory status and therefore reducing the risk of cardiovascular diseases in hypothyroid animals.

  9. Comparison of the cleavage of pyrimidine dimers by the bacteriophage T4 and Micrococcus luteus uv-specific endonucleases

    International Nuclear Information System (INIS)

    Gordon, L.K.; Haseltine, W.A.

    1980-01-01

    A comparison was made of the activity of the uv-specific endonucleases of bacteriophage T4 (T4 endonuclease V) and of Micrococcus luteus on ultraviolet light-irradiated DNA substrates of defined sequence. The two enzyms cleave DNA at the site of pyrimidine dimers with the same frequency. The products of the cleavage reaction are the same. The pyrimidine dimer DNA-glycosylase activity of both enzymes is more active on double-stranded DNA than it is on single-stranded DNA

  10. Effects of excess maternal thyroxin on the bones of rat offspring from birth to the post-weaning period.

    Science.gov (United States)

    Maia, Mariana Zanini; Santos, Gianne Karla; Batista, Ana Claudia Moura; Reis, Amanda Maria Sena; Silva, Juneo Freitas; Ribeiro, Lorena Gabriela Rocha; Ocarino, Natália de Melo; Serakides, Rogéria

    2016-04-01

    Objective To evaluate, in rat offspring, bone changes induced by excess maternal thyroxin during pregnancy and lactation, and to assess the reversibility of these changes after weaning. Material and methods Twenty Wistar rats were distributed in two groups, hyperthyroid and control, that were treated daily with L-thyroxin (50 mcg/animal) and placebo, respectively. The treatment was initiated seven days before mating and continued throughout pregnancy and lactation. From every female of each of the two groups, two offspring were euthanized after birth, two at 21 days of age (weaning), and two at 42 days of age (21 days after weaning). In newborns, the length of pelvic and thoracic limbs were measured, and in the other animals, the length and width of the femur and humerus were measured. Bones were dissected, decalcified, embedded in paraffin, and analyzed histomorphometrically. Results Excess maternal thyroxin significantly reduced the length of the pelvic limb in neonates. In 21-day-old individuals, excess maternal thyroxine reduced the length and the width of the femur and the humerus. It also increased thickness of the epiphyseal plate and the percentage of trabecular bone tissue. In 42-day-old individuals, there were no significant differences between groups in relation to the parameters evaluated in the previous periods. Conclusion Excess maternal thyroxine reduced growth in suckling rats both at birth and at weaning, and it also increased the percentage of trabecular bone tissue in 21-day-old animals. These changes, however, were reversible at 42 days, i.e., 21 days after weaning. Arch Endocrinol Metab. 2016;60(2):130-7.

  11. Low maternal free thyroxine concentrations during early pregnancy are associated with impaired psychomotor development in infancy

    NARCIS (Netherlands)

    Pop, V. J.; Kuijpens, J. L.; van Baar, A. L.; Verkerk, G.; van Son, M. M.; de Vijlder, J. J.; Vulsma, T.; Wiersinga, W. M.; Drexhage, H. A.; Vader, H. L.

    1999-01-01

    Maternal thyroid function during early pregnancy is an important determinant of early fetal brain development because the fetal thyroid is unable to produce any T4 before 12-14 weeks' gestation. Overt maternal hypothyroidism as seen in severe iodine-deficient areas is associated with severely

  12. Determining total thyroxine with the aid of the homogeneous enzyme immunoassay

    International Nuclear Information System (INIS)

    Vogt, W.

    1978-01-01

    Total thyrozine values obtained with the aid of the homogeneous enzyme immunoassay are compared with those delivered by the RIA and the efficiency of the EMIT technique is evaluated. Some results obtained via Enzymun-T4, a heterologous enzyme immunoassay, are also given. (VJ) 891 VJ [de

  13. Negligible effects of nonesterified fatty acids on serum thyroxine analysis by competitive protein-binding radioassay on Sephadex and by radioimmunoassay

    International Nuclear Information System (INIS)

    Alexander, N.M.; Nishimoto, M.

    1978-01-01

    Values for thyroxine by our competitive protein-binding assay on Sephadex (I) and by radioimmmunoassy (II) were identical for sera containing markedly increased concentrations of endogenous nonesterified fatty acids. Addition of as much as 5 mmol of long-chain saturated fatty acids per liter to normal serum had no significant effect on the thyroxine values by I; larger concentrations (10 mmol/liter) spuriously increased values by 20 to 30%. Added unsaturated fatty acids (1 mmol/liter) were without effect on procedure I, but spurious elevations in thyroxine appeared when concentrations were further increased up to 10 mmol/liter. The spurious effects by 2 to 5 mmol of added oleate and arachidonate (the most potent inhibitor of thyroxine binding to thyroxine-binding globulin) per liter could be reversed by washing the Sephadex columns with additional barbital buffer before binding with thyroxine-binding globulin (a step that is done on the gel). Three different II procedures were unaffected by as much as 5 mmol of added fatty acids per liter, but moderate spurious increases were noted with 10 mmol of oleate per liter. We conclude that method I is reliable for thyroxine analysis in nearly all sera from human subjects, because the concentrations of unsaturated fatty acids present either in vitro or in vivo are seldom large enough to interfere

  14. Quantification of thyroxine by the selective photoluminescence quenching of L-cysteine–ZnS quantum dots in aqueous solution containing hexadecyltrimethylammonium bromide

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sarzamin; Carneiro, Leonardo S.A. [Chemistry Department, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro-RJ (Brazil); Romani, Eric C.; Larrudé, Dunieskys G. [Physics Department, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900, Rio de Janeiro-RJ (Brazil); Aucelio, Ricardo Q., E-mail: aucelior@puc-rio.br [Chemistry Department, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro-RJ (Brazil)

    2014-12-15

    The determination of L-thyroxine is proposed based on the photoluminescence quenching effect caused on the L-cysteine modified ZnS quantum dots (L-cysteine ZnS QDs) aqueous dispersion. Under optimum conditions, the analytical response followed a Stern–Volmer model and the experimental conditions were adjusted to enable a robust and reproducible photoluminescence signal. The linear response observed in the quantum dots aqueous dispersion covered the L-thyroxine concentration from the LOQ (2.0×10{sup −8} mol L{sup −1}) to 4.0×10{sup −6} mol L{sup −1}. The approach was tested in the determination of L-thyroxine in pharmaceutical formulations used to treat patients with thyroid gland disorder. The percent recoveries in controlled samples were between 93.3 and 103%. Analyte fortified saliva was also evaluated as a possible sample for L-thyroxine monitoring of a patient under treatment. It was identified a static type of photoluminescence quenching caused by L-thyroxine. - Highlights: • L-cysteine ZnS QDs were used as a photoluminescent probe to detect L-thyroxine. • Intensity of probe decreases following a Stern–Volmer model. • The method can detect down ng L{sup −1} levels of L-thyroxine in the probe dispersion. • Method was used to determinate of L-thyroxine in saliva and in pharmaceuticals. • Mechanism of interaction between L-thyroxine and quantum dots was studied.

  15. Wear behaviors of pure aluminum and extruded aluminum alloy (AA2024-T4) under variable vertical loads and linear speeds

    Science.gov (United States)

    Jung, Jeki; Oak, Jeong-Jung; Kim, Yong-Hwan; Cho, Yi Je; Park, Yong Ho

    2017-11-01

    The aim of this study was to investigate the transition of wear behavior for pure aluminum and extruded aluminum alloy 2024-T4 (AA2024-T4). The wear test was carried using a ball-on-disc wear testing machine at various vertical loads and linear speeds. The transition of wear behaviors was analyzed based on the microstructure, wear tracks, wear cross-section, and wear debris. The critical wear rates for each material are occurred at lower linear speed for each vertical load. The transition of wear behavior was observed in which abrasion wears with the generation of an oxide layer, fracture of oxide layer, adhesion wear, severe adhesion wear, and the generation of seizure occurred in sequence. In case of the pure aluminum, the change of wear debris occurred in the order of blocky, flake, and needle-like debris. Cutting chip, flake-like, and coarse flake-like debris was occurred in sequence for the extruded AA2024-T4. The transition in the wear behavior of extruded AA2024-T4 occurred slower than in pure aluminum.

  16. The efficacy of superselective intra-arterial infusion in patients with T4 oral cancer. Comparison with conventional chemotherapy

    International Nuclear Information System (INIS)

    Arakaki, Keiichi; Arasaki, Akira; Kano, Takeshi

    2009-01-01

    Since 1985, we have applied systematic treatment to improve radicality and postoperative oral dysfunction, as well as maxillofacial deformity. However, most T4 cases of oral cancer have remained difficult to treat, and diverse methods and results for progressive cancer have been reported by many institutions. For high-grade malignancy cases, we changed the treatment from bleomycin or cisplatin in induction chemotherapy to targeted intra-arterial infusions of carboplatin with radiation-combined therapy. In this study, we compared the effects of conventional therapy with targeted intra-arterial infusions of carboplatin for T4 cases of oral cancer. In this retrospective review, we analyzed a subset of patients who were treated with induction chemotherapy using bleomycin (BLM) and targeted intra-arterial infusions of carboplatin (CBDCA) with radiation-combined therapy patients who received treatment between June 1985 and December 2006. Of the 105 patients who had T4 disease, the proportion with grade IIb to IV in the carboplatin with radiation-combined therapy (88.9%) was higher than that in induction chemotherapy (45.0%). Targeted chemoradiation therapy followed by surgical salvage is a highly effective approach for the regional control of patients with T4, although additional strategies are required to address the problem of distant metastases. (author)

  17. Investigation of the T4 and T6 heat treatment cycles of semi-solid processed aluminium alloy A356

    CSIR Research Space (South Africa)

    Moller, H

    2008-01-01

    Full Text Available of the solution treatment time at 540 C from 6 hours to 1 hour does not alter the T4 or T6 tensile properties of the SSM processed A356 alloy. Slightly better impact properties are obtained with the shorter solution treatment. This could lead to time and energy...

  18. Esophageal motion characteristics in thoracic esophageal cancer: Impact of clinical stage T4 versus stages T1-T3

    Directory of Open Access Journals (Sweden)

    Yuta Kobayashi, MS

    2016-10-01

    Conclusions: The EM and the ITV margins in cT4 were significantly smaller than those in cT1-T3. The NM and the ITV margins of abdominal LNs were much larger than those of cervicothoracic LNs and the esophagus. In clinical radiation therapy planning for esophageal cancer, we should take cT stage into consideration.

  19. Development and characterization of radioimmunoassay methods for the measurement of iodothyronines (T4, T3 and rT3)

    International Nuclear Information System (INIS)

    Russo, E.M.K.; Vieira, J.G.H.; Barros Maciel, R.M. de; Fonseca, R.M.G.

    1982-01-01

    The experience acquired in the development of radioimmunoassay for T 4 , T 3 and rT 3 in unextrated serum is described. Antisera were produced in rabbits using iodothyronines conjugated to bovine serum albumin: the antisera selected provided the development of sensitive and specific radioassay methods. Stable high activity T 3 , T 4 and rT 3 tracers were prepared by iodination of 3,5 T 2 , T 3 and 3,3' T 2 by the chloramine-T method, and purified by column chromatography on Sephadex G25. Binding of those iodothyronines to endogenous serum proteins was blocked by including 8-aniline-1-naphtalene sulphonic acid (ANSA) in the T 4 and T 3 assays and thymerosal in the rT 3 assay. Normal values were defined in 46 healthy euthyroid adults of both sexes: T 4 = 7,1 +- 1,3μg/dl; T 3 = 139 +- 35ng/dl and rT 3 = 18,0 +- 7,9ng/dl. (Author) [pt

  20. Recovery of the accumulation ability of thiomethyl-β-galactoside in Escherichia coli after bacteriophage T4 infection

    International Nuclear Information System (INIS)

    Saijo, N.; Okamoto, K.

    1976-01-01

    Effects of uv-irradiated and unirradiated T4 phage infection on the β-galactoside accumulation ability in Escherichia coli have been examined by the use of 14 C-labeled thiomethyl-β-galactoside (TMG). Under conditions where a synchronous adsorption of phage takes place, the cellular ability for TMG accumulation is found to be largely inhibited immediately after phage adsorption but it recovers with time to a new level, which is dependent on the multiplicity of infection. When cells are infected with uv-irradiated T4 at the same multiplicity as that of unirradiated phage, the cellular accumulation ability is more severely inhibited and there is no recovery from the inhibition. The recovery process in T4-infected cells is mostly sensitive to puromycin. These results suggest that the initial inhibition of the TMG accumulation ability is probably caused by the adsorption of phage coats, and the subsequent restoration occurs through the action of a phage-directed protein(s). In the recovery process, no new transport system appears to be involved. The restored ability of TMG accumulation is resistant to the action of superinfecting uv phage. However, different mechanisms appear to be operating in T4-infected cells for the establishment of resistance to ghosts and for the recovery from the phage coat-induced inhibition

  1. Observation on the stability of the solid phase microparticles separating technique in T3, T4 radioimmunoassay

    International Nuclear Information System (INIS)

    Chen Guangliang; Chen Xunmin

    1995-01-01

    The solid phase T 3 ,T 4 RIA is adopted at various laboratories. The data analysis from the effective dose and quality control of samples indicates that the separation technique is of good effect and high stability. It is an effective separation technique for the quality control in RIA

  2. The breast cancer antigen 5T4 interacts with Rab11, and is a target and regulator of Rab11 mediated trafficking.

    Science.gov (United States)

    Harris, Janelle L; Dave, Keyur; Gorman, Jeffrey; Khanna, Kum Kum

    2018-06-01

    5T4 is a transmembrane glycoprotein with limited expression in normal adult tissues and expression in some solid tumours. It is unclear whether 5T4 is preferentially expressed by stem or differentiated cell types. Modes of 5T4 regulation are unknown despite its ongoing development as a cancer immunotherapy target. Our aims were to clarify the differentiation status of 5T4 expressing cells in breast cancer and to understand the mechanism underlying 5T4 membrane presentation. We analysed 5T4 expression in breast cancer cell populations by flow cytometery and found that 5T4 is highly expressed on differentiated cells, where it localizes to focal adhesions. Using immunoprecipitation and mass spectrometry, we identified interactions between 5T4 and the membrane trafficking proteins Rab11, Rab18 and ARF6. Mechanistically we found that Rab11 and Rab18 have oppositional roles in controlling expression and surface presentation of 5T4. 5T4 depletion stabilizes Rab11 protein expression with a consequent stimulation transferrin surface labelling, indicating that 5T4 represses endocytic activity. Successful immunotherapeutic targeting of 5T4 requires surface presentation and different immunotherapy strategies require surface presentation versus endocytosis. While breast cancer cells with high 5T4 surface expression and rapid cell surface turnover would be susceptible to antibody-drug conjugates that rely on intracellular release, 5T4 positive cells with lower expression or lower turnover may still be responsive to T-cell mediated approaches. We find that endocytosis of 5T4 is strongly Rab11 dependent and as such Rab11 activity could affect the success or failure of 5T4-targetted immunotherapy, particularly for antibody-drug conjugate approaches. In fact, 5T4 itself represses Rab11 expression. This newly uncovered relationship between Rab11 and 5T4 suggests that breast tumours with high 5T4 expression may not have efficient endocytic uptake of 5T4-targetted immunotherapeutics

  3. Plasma Dopamine-Beta-Hydroxylase as an Index of Peripheral Noradrenergic Activity

    Science.gov (United States)

    1981-08-17

    and an acidic buffer are included in the DBH mix along with the substrate. In addition, a monoamine oxidase inhibitor is added to the mix to prevent ...diseases (41 , 155, 97). Patients with hyperthyroidism have significantly lower DBH values than those of controls (190, 192), and patients with hypo... hyperthyroidism , and plasma DBH activity was inversely related to thyroxin levels during therapy for hypothyroidism. Although this and plasma NE

  4. COMPARACIÓN DE LOS NIVELES SÉRICOS DE TSH Y T4 LIBRE EN BOVINOS

    Directory of Open Access Journals (Sweden)

    J. H. Osorio

    2016-01-01

    Full Text Available El presente estudio tuvo como objetivo determinar los niveles de TSH y T4 libre (T4L en bovinos, diferenciados por género y edad, y conocer su comportamiento frente a dichas variables. Se obtuvieron 133 muestras de sangre de bovinos F1 en estado de ayuno y con ellas se establecieron cuatro grupos (36 machos y 20 hembras menores de 18 meses y 47 machos y 30 hembras mayores de 24 meses. Se determinaron los niveles de TSH y T4L mediante inmunoensayo enzimático. Los valores promedio de TSH (μUI/ml fueron de 1,86 para las hembras jóvenes y adultas, 1,88 para los machos jóvenes y 1,99 para los machos adultos. El valor P del test F fue mayor a 0,05 en todos los grupos y, por lo tanto, no hay diferencia estadísticamente significativa, con una confiabilidad del 95%. Los valores promedio de T4L (ng/dl para hembras jóvenes, hembras adultas, machos jóvenes y machos adultos fueron de 0,84; 0,62; 0,67 y 0,85, respectivamente. El valor P del test F fue menor a 0,05 en todos los grupos, indicando diferencia estadísticamente significativa, con 95% de confiabilidad. En conclusión, no se encontraron efectos de sexo y edad sobre las concentraciones de TSH, mientras que los niveles de T4L exhiben diferencia significativa entre estas variables; en efecto, entre los bovinos jóvenes, las hembras tienen niveles más elevados; por su parte, en los adultos, son los machos los que presentan valores superiores.

  5. Variation in the biochemical response to l-thyroxine therapy and relationship with peripheral thyroid hormone conversion efficiency

    OpenAIRE

    Midgley, John E M; Larisch, Rolf; Dietrich, Johannes W; Hoermann, Rudolf

    2015-01-01

    Several influences modulate biochemical responses to a weight-adjusted levothyroxine (l-T4) replacement dose. We conducted a secondary analysis of the relationship of l-T4 dose to TSH and free T3 (FT3), using a prospective observational study examining the interacting equilibria between thyroid parameters. We studied 353 patients on steady-state l-T4 replacement for autoimmune thyroiditis or after surgery for malignant or benign thyroid disease. Peripheral deiodinase activity was calculated a...

  6. Thyroxine determination in serum by radioimmunoassay and competitive protein-binding analysis (simultaneous study using four test kits)

    International Nuclear Information System (INIS)

    Wagner, K.

    1978-01-01

    Three commercial test kits for radioimmunological T 4 -determination have been tested (T 4 -RIA Abbott, RIA-mat T 4 , T 4 -RIA Henning). The RIA method has also been compared with a CPBA test (Tetralute) for routine application. 1) The results show that CPBA (Tetralute) is superior over the three radioimmuno-assays with regard to intra-assay variance. The T 4 -RIA Abbott has been inferior to the two other RIA under test and to the Tetralute with regard to inter-assay variance. 2) The four test kits show significant differences and considerable deviations from the given nominal values in comparison with the mean values of two control sera. A control for correctness does not seem to be appropriate as it cannot be decided which of the test kits yields the true value of T 4 content. No systematic difference has been observed between RIA and CPBA in the determination of T 4 in control sera. 3) No detectable difference has been found among the RIA-T 4 test kits and comparing them with the CBPA test regarding their diagnostic precision. A good correlation of T 4 values of euthyroid patients comparing the Tetralute and the three radioimmunological test kits. The mean values of euthyroid sera obtained by the three radioimmuno-assays and the Tetralute are not in agreement with each other. (orig.) [de

  7. The epidemiologic study: the serum levels of TSH, T4, T3 and autoantibodies in the Polish population

    International Nuclear Information System (INIS)

    Gardas, A.

    1991-01-01

    In 1986-1990 epidemiologic studies on the thyroid diseased frequency in the Polish population were undertaken. During this studies the serum levels of TSH, T 4 , T 3 and autoantibodies were estimated in more then 30 thousand people. TSH was estimated in 30749, T 4 in 30928, T 3 in 30621 and autoantibodies in 31265 randomly chosen people in 5 districts. We have arbitrarily established the normal range for TSH to be between 0.4-3.8 μIU/ml, for T 4 4.4-12.5 μg and for T 3 0.9-1.95 ng/ml. The tested group has been divide in 4 subgroup: girls and boys from 1 to 15 years of age of the Chernobyl accident, men and women from 15 to 50 years of age at the date of the accident. TSH values in the normal range were found in 85 to 92% of the tested population, depending on the subgroup. T 4 vales in the normal range were found in 85 to 92% of the tested groups. T 3 vales in the normal range were found in 86 to 93% of the tested groups. The absence on any kind of autoantibodies was established in 89.7% of the tested population. TSH values was above the normal range (above 3.8 μIU/ml) in 3.4% of boys, 4.3% girls, 3.2% men and 3.8% women. TSH vales below the normal range (less the 0.4 μIU/ml) were found in 4.3% boys, 5% girls, 10% men and 11.2% women. T 4 values above the normal range (higher then 12.5 μg%) were found in 12.9% boys, 12.6% girls, 4.6% men and 5.9% women. T 4 vales below the normal range (less then 4.4 μg%) were detected in 0.9% boys, 1.4% girls, 2.4% men and 2.0% women. T 3 values higher then 1.95 ng/ml were found in 10.8% of boys, 11.5% girls, 2.6% men and 3.5% women. The percentage of values above of below the arbitrarily chosen normal range depends on the age and sex group. (author). 5 refs, 4 tabs

  8. Study on changes of serum lipid profile after withdrawl of levo-thyroxine replacement therapy in patients with radical thyroidectomy for cancer

    International Nuclear Information System (INIS)

    Yang Shumin; Yu Lili; Dong Lin; Zhu Gaohong; Zhang Jijian

    2010-01-01

    Objective: To study the changes of serum lipid profile after withdrawl of levo-thyroxine replacement for 4 weeks in patient with radical thyroidectomy for cancer. Methods: Serum thyroid hormones (FT 3 , FT 4 , sTSH, with RIA) levels and lipid profile (Total cholesterol, triglycerides, LDL, HDL, apolipoprotein A-I, apolipoprotein B and Lp (a), with biochemistry) were determined in 46 patients with thyroid carcinoma after operation both during and after 4 weeks' withdrawl of levo-thyroxine replacement treatment. Results: Serum FT 3 , FT 4 levels decreased significantly and serum sTSH, TC, TG, LDL, apo-B, Lp (a) levels increased significantly after 4 weeks' withdrawl of levo-thyroxine replacement (vs during treatment, P 0.05). Conclusion: Hyperlipidaemia did develop in the hypothyroid patients after withdrawl of levo-thyroxine replacement but the degree of which did not not necessarily correlate with the increment of sTSH levels. (authors)

  9. Preliminary results of a new radioimmunoassay for thyroxine binding globulin (T.B.G.)

    International Nuclear Information System (INIS)

    Bisset, J.-P.; Sauvan, R.; Roux, F.; Hourtoule, P.

    1978-01-01

    A radioimmunoassay for the accurate measurement of T.B.G., developed by Crouzat-Reynes, was used to perform T.B.G. concentration in sera of euthyroid subjects in different clinical situations, in hypothyroid and hyperthyroid patients. In normal control, the T.B.G. concentration was not different from men and women, from young and old subjects. On the other hand, in women either pregnant or receving oral contraception, the T.B.G. levels were significantly higher than euthyro subjects. Cirrhosis of the liver and liver carcinoma were without apparent effect on T.B.G. levels because it was a too few number of patients and the group was too heterogeneous. In the group of hypothyroid and hyperthyroid patients, the T.B.G. serum concentrations were not significantly different from normal. The ratio T4/T.B.G. as I.T.L. (T4 x T3 uptake) permit to bring back in normal range T4 levels changed by extrathyroidal process; however, this ratio seems to be less interesting than standard I.T.L. The T.B.G. assay has not to be considered only as a substitution of T3 uptake because they do not study the same parameters [fr

  10. Thermal acclimation and thyroxine treatment modify the electric organ discharge frequency in an electric fish, Apteronotus leptorhynchus.

    Science.gov (United States)

    Dunlap, K D; Ragazzi, M A

    2015-11-01

    In ectotherms, the rate of many neural processes is determined externally, by the influence of the thermal environment on body temperature, and internally, by hormones secreted from the thyroid gland. Through thermal acclimation, animals can buffer the influence of the thermal environment by adjusting their physiology to stabilize certain processes in the face of environmental temperature change. The electric organ discharge (EOD) used by weak electric fish for electrocommunication and electrolocation is highly temperature sensitive. In some temperate species that naturally experience large seasonal fluctuations in environmental temperature, the thermal sensitivity (Q10) of the EOD shifts after long-term temperature change. We examined thermal acclimation of EOD frequency in a tropical electric fish, Apteronotus leptorhynchus that naturally experiences much less temperature change. We transferred fish between thermal environments (25.3 and 27.8 °C) and measured EOD frequency and its thermal sensitivity (Q10) over 11 d. After 6d, fish exhibited thermal acclimation to both warming and cooling, adjusting the thermal dependence of EOD frequency to partially compensate for the small change (2.5 °C) in water temperature. In addition, we evaluated the thyroid influence on EOD frequency by treating fish with thyroxine or the anti-thyroid compound propylthiouricil (PTU) to stimulate or inhibit thyroid activity, respectively. Thyroxine treatment significantly increased EOD frequency, but PTU had no effect. Neither thyroxine nor PTU treatment influenced the thermal sensitivity (Q10) of EOD frequency during acute temperature change. Thus, the EOD of Apteronotus shows significant thermal acclimation and responds to elevated thyroxine. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. The effects of dexamethasone (DXM) and vitamin A on the growth and metamorphosis of gamma irradiated, thyroxine induced Bufo melanostictus tadpoles

    International Nuclear Information System (INIS)

    Ahmad, M.; Haider, N.; Siddiqui, R.Q.R.

    1980-01-01

    This study deals with the effects of vitamin A and dexamethasone (DXM) on the metamorphosis of irradiated tadpoles. Results indicate that hypervitaminosis A depresses the metamorphosing action of thyroxine for several days. On the contrary, dexamethasone accelerates the action of exogenous thyroxine on tadpoles. Thus present data suggest that DXM supresses STH synthesis and promotes TSH secretion. Moreover, muscle appears to be its target tissue and DXM seems to promote the proteolytic digestion of the larval tail. (author)

  12. HUBUNGAN KANDUNGAN KLOR SERUM DENGAN HORMON T3/T4 PADA ANAK SEKOLAH DI DAERAH GONDOK ENDEMIK

    Directory of Open Access Journals (Sweden)

    Sukati Saidin

    2012-11-01

    Full Text Available ASSOCIATION OF SERUM CHLOR CONTENT WITH T3/T4 HORMONEIN SCHOOL CHILDREN IN IODINE DEFICIENCY REGION.Background: The National Mapping Survey of IDD (1998 found that 7% of sub districts In Indonesia was regarded as severe endemic goitre area (TGR>30%. The high TGR prevalence, beside as a result of low iodized salt consumption (< 30 ppm, It was assumed as the effect of exposure of goitrogenic agent such as chlorine. Based on observation in Karawang sub district showed people had food habit to consume fish contaminated by insecticide used for killing milk fish predator or salted fish which had also contaminated by insecticide used during process of fish drying. Insecticide raw material consists of chlorine which can not be broken by heat or oxidation. Previous study by Gaitan E. (1986 found that chlorine component could inhibit iodine metabolism to form mono and di-iodotyrosine as precursor of T3 and T4 hormones.Objectives: The aim of this study was to find an association of serum chlorine as a reflection of chlorine consumption from daily food with T3 and T4 hormone.Methods: Research design was case control. Study was conducted in Karawang district, West Java. The subject were elementary school children in the fourth, fifth and sixth grades with positive goitre at grade I and II by palpation. Sample size was 140 children divided into two groups, case group (70 children and control group (70 children. Main data collected was chlorine consumption from daily food, serum chlorine, serum T3 and T4 hormones as well as anthropometries.Results: The result showed that chlorine consumption from food was relatively greater in case group (135.9 ugr/day than in control group (129.9 ug/day but statistically it was not significant. Serum chlorine content in case group (1 14.8 mmol/L was significantly higher than in control group (102.1 mmol/L. Serum T4 hormone in case group (7.3 ug/dl was significantly lower than in control group (9.5 ug/dl. Serum T3 hormone in

  13. Inactivation of T4-phages by heat and γ-irradiation treatment in respect to sludge hygienization

    International Nuclear Information System (INIS)

    Farniok, C.; Turanitz, K.; Stehlik, G.; Meyrath, J.

    1977-04-01

    The effects of γ-irradiation, heat treatment and combined heat/irradiation treatments on T 4 -bacteriophages were studied and evaluated in surviving fractions. To ascertain the extent of inactivation, the formation of plaque was studied in the host organism Escherichia coli K 12 D 10. A 90-minute heat treatment of the bacteriolysat at 55 0 C did not inactivate the bacteriophages, whereas the number of plaque-forming bacteriophages was decreased by 50% at 60 0 C. At 65 0 C a linear correlation of heating period and the logarithm of relative number of phages was observed. After 30 minutes exposure to 70 0 C only few bacteriophages were traced in the plaque test. By inactivation of T 4 -phages after exposure to γ-irradiation a linear correlation of irradiation dose and the logarithm of the relative number of surviving bacteriophages was found. The combined method of heat and irradiation treatments resulted in a synergistic effect. (author)

  14. Enhanced unscheduled DNA synthesis in UV-irradiated human skin explants treated with T4N5 liposomes

    International Nuclear Information System (INIS)

    Yarosh, D.B.; Kibitel, J.T.; Green, L.A.; Spinowitz, A.

    1991-01-01

    Epidermal keratinocytes cultured from explants of skin cancer patients, including biopsies from xeroderma pigmentosum patients, were ultraviolet light-irradiated and DNA repair synthesis was measured. Repair capacity was much lower in xeroderma pigmentosum patients than in normal patients. The extent of DNA repair replication did not decline with the age of the normal patient. Treatment with T4N5 liposomes containing a DNA repair enzyme enhanced repair synthesis in both normal and xeroderma pigmentosum keratinocytes in an irradiation- and liposome-dose dependent manner. These results provide no evidence that aging people or skin cancer patients are predisposed to cutaneous malignancy by a DNA repair deficiency, but do demonstrate that T4N5 liposomes enhance DNA repair in the keratinocytes of the susceptible xeroderma pigmentosum and skin cancer population

  15. Co-administration of Apelin and T4 Protects Inotropic and Chronotropic Changes Occurring in Hypothyroid Rats

    Energy Technology Data Exchange (ETDEWEB)

    Akhondali, Zahra; Badavi, Mohammad; Dianat, Mahin, E-mail: dianat@ajums.ac.ir; Faraji, Farzaneh [Physiology Research Center and Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz (Iran, Islamic Republic of)

    2015-09-15

    One of the most important thyroid hormone targets is the cardiovascular system. Hemodynamic changes, such as decreased resting heart rate (HR), myocardial contractility, and cardiac output, and increased diastolic pressure and systemic vascular resistance, have been observed in hypothyroid patients. Moreover, in these patients, ECG changes include sinus bradycardia and low voltage complexes (P waves or QRS complexes). This study aimed at evaluating the prophylactic effect of apelin on HR changes and QRS voltage that occur in propylthiouracil (PTU)-induced hypothyroid rats. In this study, 48 adult male Wistar rats weighing 170-235g were randomly divided into 6 groups: Control group (normal saline ip injection + tap water gavage); P group (PTU 0.05%, in drinking water); A group (apelin 200 µg.kg{sup -1}.day{sup -1}, ip); PA group [co-administration of PTU and apelin]; PT group [co-administration of PTU + T4 (0.2 mg/g per day, gavage)]; and PAT group (co-administration of PTU, apelin and T4). All experiments were performed for 28 consecutive days, and then the animals were anesthetized with an ip injection of ketamine (80 mg/kg) and xylazine (12 mg/kg). Lead II electrocardiogram was recorded to calculate HR and QRS voltage. Heart rate and QRS voltage increased more significantly in the hypothyroid group that consumed both apelin and T4 (201 ± 4 beat/min, 0.71 ± 0.02 mv vs. hypothyroid 145 ± 9 beat/min, 0.563 ± 0.015 mv; respectively). The co-administration of apelin and T4 showed a protective effect on QRS voltage and HR in PTU‑induced hypothyroid rats.

  16. Co-administration of Apelin and T4 Protects Inotropic and Chronotropic Changes Occurring in Hypothyroid Rats

    Directory of Open Access Journals (Sweden)

    Zahra Akhondali

    2015-01-01

    Full Text Available Abstract Background: One of the most important thyroid hormone targets is the cardiovascular system. Hemodynamic changes, such as decreased resting heart rate (HR, myocardial contractility, and cardiac output, and increased diastolic pressure and systemic vascular resistance, have been observed in hypothyroid patients. Moreover, in these patients, ECG changes include sinus bradycardia and low voltage complexes (P waves or QRS complexes. Objective: This study aimed at evaluating the prophylactic effect of apelin on HR changes and QRS voltage that occur in propylthiouracil (PTU-induced hypothyroid rats. Method: In this study, 48 adult male Wistar rats weighing 170-235g were randomly divided into 6 groups: Control group (normal saline ip injection + tap water gavage; P group (PTU 0.05%, in drinking water; A group (apelin 200 µg.kg-1.day-1, ip; PA group [co-administration of PTU and apelin]; PT group [co-administration of PTU + T4 (0.2 mg/g per day, gavage]; and PAT group (co-administration of PTU, apelin and T4. All experiments were performed for 28 consecutive days, and then the animals were anesthetized with an ip injection of ketamine (80 mg/kg and xylazine (12 mg/kg. Lead II electrocardiogram was recorded to calculate HR and QRS voltage. Results: Heart rate and QRS voltage increased more significantly in the hypothyroid group that consumed both apelin and T4 (201 ± 4 beat/min, 0.71 ± 0.02 mv vs. hypothyroid 145 ± 9 beat/min, 0.563 ± 0.015 mv; respectively. Conclusion: The co-administration of apelin and T4 showed a protective effect on QRS voltage and HR in PTU‑induced hypothyroid rats.

  17. Metal ions-binding T4 lysozyme as an intramolecular protein purification tag compatible with X-ray crystallography

    Czech Academy of Sciences Publication Activity Database

    Bouřa, Evžen; Bäumlová, Adriana; Chalupská, Dominika; Dubánková, Anna; Klíma, Martin

    2017-01-01

    Roč. 26, č. 6 (2017), s. 1116-1123 ISSN 0961-8368 R&D Projects: GA ČR(CZ) GJ17-07058Y; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : phage T4 * lysozyme * endolysin * histidine tag * protein purification * crystal structure Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 2.523, year: 2016

  18. Serum thyroid stimulating hormone, total and free T4 during the neonatal period: Establishing regional reference intervals

    Directory of Open Access Journals (Sweden)

    Sara Sheikhbahaei

    2014-01-01

    Full Text Available Context: Congenital hypothyroidism (CH, the most common etiology of preventable mental retardation in children, is estimated to be more prevalent among Asian population. Aims: Since thyroid function tests (TFTs varied among different ages and geographical regions, in this study, the neonatal thyroid reference intervals in a healthy neonatal population is determined for the first time in Iran. Settings and Design: A cross-sectional study performed on 246 healthy term newborns aged between 2 days and 1 month. Materials and Methods: Blood samples were obtained by venipuncture from all subjects. The median, 2.5 th , 5 th , 95 th , and 97.5 th percentile of serum thyroid-stimulating hormone (TSH, as well as the total and free T4 were assessed among different age groups. Statistical Analysis Used: Predictive Analytics Software (PASW Statistics 18 was used for the analysis. Results: Serum TSH, total and free T4 concentration peaked in 5 th to 7 th days of life, continued over 2 weeks, then decreased and started reaching to adult reference range. A significant negative correlation between age and serum concentration of TSH (P = 0.02, total T4 (P = 0.01 and free T4 (P = 0.01 was found. Conclusion: This study yielded fairly different values for TFTs compared compared values found in other countries and also different from values reported for laboratory kits we used. These differences were assumed to be due to variations in ethnicity, age, and laboratory methods used. Due to the lack of international standardization, conducting multicenter studies helps in making a more precise evaluation of thyroid status in neonates.

  19. Concurrent chemoradiotherapy for T4 and/or M1 LYM squamous cell carcinoma of the esophagus

    Energy Technology Data Exchange (ETDEWEB)

    Miyata, Yoshinori; Seki, Shigeki [Saku Central Hospital, Usuda, Nagano (Japan); Ohtsu, Atsushi; Kaneko, Kazuhiro; Nakamura, Akira

    2000-07-01

    A phase II study was conducted to investigate the efficacy and feasibility of chemoradiotherapy for locally advanced carcinoma of the esophagus. Fifty-four patients with clinical T4 and/or M1 LYM squamous cell carcinoma of the esophagus were enrolled. Patients received protracted infusions of fluorouracil 400 mg/m{sup 2}/24 hours on days 1 to 5 and 8 to 12, 2-hour infusions of cisplatin 40 mg/m{sup 2} on days 1 and 8, and concurrent radiotherapy at a dose of 30 Gy in 15 fractions over 3 weeks. Filgrastim was prophylactically administered to 35 patients. This schedule was repeated twice every 5 weeks, for a total radiation dose of 60 Gy followed by two courses of fluorouracil (800 mg/m{sup 2}/24 hours for 5 days) and cisplatin (80 mg/m{sup 2} on day 1). There were 36 patients with T4 disease and 33 with M1 LYM. Forty-nine patients (91%) completed the chemoradiotherapy segment. The 18 patients (33%) who achieved a complete response included nine (25%) of the 36 with T4 disease and nine (50%) of the 18 with non-T4 disease. Major toxicities were leukopenia and esophagitis; there were four (7%) treatment-related deaths. Prophylactic filgrastim reduced the incidence of grade 3 or worse leukopenia without improving dose-intensity or response. With a median follow-up duration of 43 months, median survival time was 9 months. The 3-year survival rate was 23%. Despite its significant toxicity, this combined modality seemed to have curative potential even in cases of locally advanced carcinoma of the esophagus. (author)

  20. Automated measurement of serum thyroxine with the ''AIRA II,'' as compared with competitive protein binding and radioimmunoassay

    International Nuclear Information System (INIS)

    Reese, M.G.; Johnson, L.V.R.

    1978-01-01

    Two conventional serum thyroxine assays, run in separate laboratories, one by competitive protein binding and one by radioimmunoassay, were used to evaluate the automated ARIA II (Becton Dickinson Immunodiagnostics) serum thyroxine assay. Competitive protein binding as compared to ARIA II with 111 clinical serum samples gave a slope of 1.04 and a correlation coefficient of 0.94. The radioimmunoassay comparison to ARIA II with 53 clinical serum samples gave a slope of 1.05 and a correlation coefficient of 0.92. The ARIA II inter-assay coefficient of variation for 10 replicates of low, medium, and high thyroxine serum samples was 6.2, 6.0, and 2.9%, respectively, with an inter-assay coefficient of variation among 15 different assays of 15.5, 10.1, and 7.9%. The automated ARIA II, with a 2.2-min cycle per sample, gives results that compare well with those by manual methodology

  1. Maternal environment and craniofacial growth: geometric morphometric analysis of mandibular shape changes with in utero thyroxine overexposure in mice.

    Science.gov (United States)

    Kesterke, Matthew J; Judd, Margaret A; Mooney, Mark P; Siegel, Michael I; Elsalanty, Mohammed; Howie, R Nicole; Weinberg, Seth M; Cray, James J

    2018-07-01

    An estimated 3% of US pregnancies are affected by maternal thyroid dysfunction, with between one and three of every 1000 pregnancies being complicated by overactive maternal thyroid levels. Excess thyroid hormones are linked to neurological impairment and excessive craniofacial variation, affecting both endochondral and intramembranous bone. Using a geometric morphometric approach, this study evaluates the role of in utero thyroxine overexposure on the growth of offspring mandibles in a sample of 241 mice. Canonical variate analysis utilized 16 unilateral mandibular landmarks obtained from 3D micro-computed tomography to assess shape changes between unexposed controls (n = 63) and exposed mice (n = 178). By evaluating shape changes in the mandible among three age groups (15, 20 and 25 days postnatal) and different dosage levels (low, medium and high), this study found that excess maternal thyroxine alters offspring mandibular shape in both age- and dosage-dependent manners. Group differences in overall shape were significant (P < 0.001), and showed major changes in regions of the mandible associated with muscle attachment (coronoid process, gonial angle) and regions of growth largely governed by articulation with the cranial base (condyle) and occlusion (alveolus). These results compliment recent studies demonstrating that maternal thyroxine levels can alter the cranial base and cranial vault of offspring, contributing to a better understanding of both normal and abnormal mandibular development, as well as the medical implications of craniofacial growth and development. © 2018 Anatomical Society.

  2. Risk of Depression, Chronic Morbidities, and l-Thyroxine Treatment in Hashimoto Thyroiditis in Taiwan: A Nationwide Cohort Study.

    Science.gov (United States)

    Lin, I-Ching; Chen, Hsin-Hung; Yeh, Su-Yin; Lin, Cheng-Li; Kao, Chia-Hung

    2016-02-01

    The aim of this study was to evaluate the risk of depression in and effect of L-thyroxine therapy on patients with Hashimoto thyroiditis (HT) in Taiwan.In this retrospective, nationwide cohort study, we retrieved data from the Longitudinal Health Insurance Database 2000. We collected data of 1220 patients with HT and 4880 patients without HT for the period 2000 to 2011. The mean follow-up period for the HT cohort was 5.77 years. Univariate and multivariate Cox proportional hazards regression models were used to estimate the risk of depression in the HT cohort.In the HT cohort, 89.6% of the patients were women. Compared with the non-HT cohort, the HT cohort exhibited a higher prevalence of diabetes mellitus, hyperlipidemia, and coronary artery disease. Furthermore, the HT cohort showed a higher overall incidence of depression compared with the non-HT cohort (8.67 and 5.49 per 1000 person-year; crude hazard ratio [HR] = 1.58, 95% confidence interval [CI] = 1.18-2.13). The risk of depression decreased after administration of L-thyroxine treatment for more than 1 year (adjusted HR = 1.02; 95% CI = 0.66-1.59).In Taiwan, the overall incidence of depression was greater in the young HT cohort. L-thyroxine treatment reduced the risk of depression.

  3. Changes in arterial stiffness, carotid intima-media thickness, and epicardial fat after L-thyroxine replacement therapy in hypothyroidism.

    Science.gov (United States)

    del Busto-Mesa, Abdel; Cabrera-Rego, Julio Oscar; Carrero-Fernández, Lisván; Hernández-Roca, Cristina Victoria; González-Valdés, Jorge Luis; de la Rosa-Pazos, José Eduardo

    2015-01-01

    To assess the relationship between primary hypothyroidism and subclinical atherosclerosis and its potential changes with L-thyroxine replacement therapy. A prospective cohort study including 101 patients with primary hypothyroidism and 101 euthyroid patients as controls was conducted from July 2011 to December 2013. Clinical, anthropometrical, biochemical, and ultrasonographic parameters were assessed at baseline and after one year of L-thyroxine replacement therapy. At baseline, hypothyroid patients had significantly greater values of blood pressure, total cholesterol, VLDL cholesterol, left ventricular mass, epicardial fat, and carotid intima-media thickness as compared to controls. Total cholesterol, VLDL cholesterol, ventricular diastolic function, epicardial fat, carotid intima-media thickness, carotid local pulse wave velocity, pressure strain elastic modulus, and β arterial stiffness index showed a significant and positive correlation with TSH levels. After one year of replacement therapy, patients with hypothyroidism showed changes in total cholesterol, VLDL cholesterol, TSH, carotid intima-media thickness, and arterial stiffness parameters. Primary hypothyroidism is characterized by an increased cardiovascular risk. In these patients, L-thyroxine replacement therapy for one year is related to decreased dyslipidemia and improvement in markers of subclinical carotid atherosclerosis. Copyright © 2014 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

  4. Degradation of Phytate Pentamagnesium Salt by Bacillus sp. T4 Phytase as a Potential Eco-friendly Feed Additive

    Science.gov (United States)

    Park, Inkyung; Lee, Jaekoo; Cho, Jaiesoon

    2012-01-01

    A bacterial isolate derived from soil samples near a cattle farm was found to display extracellular phytase activity. Based on 16S rRNA sequence analysis, the strain was named Bacillus sp. T4. The optimum temperature for the phytase activity toward magnesium phytate (Mg-InsP6) was 40°C without 5 mM Ca2+ and 50°C with 5 mM Ca2+. T4 phytase had a characteristic bi-hump two pH optima of 6.0 to 6.5 and 7.4 for Mg-InsP6. The enzyme showed higher specificity for Mg-InsP6 than sodium phytate (Na-InsP6). Its activity was fairly inhibited by EDTA, Cu2+, Mn2+, Co2+, Ba2+ and Zn2+. T4 phytase may have great potential for use as an eco-friendly feed additive to enhance the nutritive quality of phytate and reduce phosphorus pollution. PMID:25049504

  5. Changes in Serum TSH and T4 Levels after Switching the Levothyroxine Administration Time from before Breakfast to before Dinner

    Directory of Open Access Journals (Sweden)

    S. Ala

    2015-01-01

    Full Text Available Background. Levothyroxine is commonly used in the treatment of patients with hypothyroidism. Levothyroxine is most often administered in the morning, on an empty stomach, in order to increase its oral absorption. However, many patients have difficulties taking levothyroxine in the morning. Aim. The aim of this study was evaluating the effect of changing levothyroxine administration time from before breakfast to before dinner on the serum levels of TSH and T4. Subjects and Methods. Fifty patients between 18 and 75 years old with hypothyroidism were included in the study and were randomly divided into two groups. Each group received two tablets per day (one levothyroxine tablet and one placebo tablet 30 minutes before breakfast and 1 hour before dinner. After two months, the administration time for the tablets was changed for each group, and the new schedule was continued for a further two-month period. The serum TSH and T4 levels were measured before and after treatment in each group. Results. Changing the levothyroxine administration time resulted in 1.47 ± 0.51 µIU/mL increase in TSH level (p=0.001 and 0.35 ± 1.05 µg/dL decrease in T4 level (p=0.3. Conclusions. Changing the levothyroxine administration time from before breakfast to before dinner reduced the therapeutic efficacy of levothyroxine.

  6. Clinical evaluation of thyroxine-binding globulin (TBG) as a marker of liver tumors

    Energy Technology Data Exchange (ETDEWEB)

    Terui, S

    1984-03-01

    This investigation was undertaken to evaluate thyroxine-binding globulin (TGB) as a marker of liver tumors, in conjection with the liver scintigram. Of 30 patients with primary hepatocellular carcinoma (PHC), 22 (73.3%) showed significantly higher TBG concentrations. Eight patients (26.7%) showed normal TBG concentrations. In the case of 27 our of 30 patients with definite liver tumors, defects were apparent on the scintigrams. But seven of them had normal TBG concentrations in spite of the defects on the scintigrams. Out of 33 postoperative patients with liver metastasis, 28 (84%) had a raised TBG concentration. Only five (15.2%) had a normal TBG level. In 31 patients (93.9%) out of 33 with liver metastasis, a definite diagnosis was made on the basis of the liver scintigram. In 28 (90.3%) of these 31 people, the TBG concentration was higher than normal. Among 63 patients with liver tumors, both primary and metastatic, the test sensitivity for liver tumors was 92.1% (58/63) based on the accuracy of the liver scintigram. It was 79.4% (50/63) based on the TBG measurement. Why TBG increases to such an extent in spite of the euthyroid state remains unexplained. But it may be concluded that elevated TBG with positive liver scintigram furnishes a sensitive, fairly reliable, nonspecific tumor marker to determine liver tumors, especially in the case of liver metastasis.

  7. Clinical evaluation of thyroxine-binding globulin (TBG) as a marker of liver tumors

    International Nuclear Information System (INIS)

    Terui, S.

    1984-01-01

    This investigation was undertaken to evaluate thyroxine-binding globulin (TGB) as a marker of liver tumors, in conjection with the liver scintigram. Of 30 patients with primary hepatocellular carcinoma (PHC), 22 (73.3%) showed significantly higher TBG concentrations. Eight patients (26.7%) showed normal TBG concentrations. In the case of 27 our of 30 patients with definite liver tumors, defects were apparent on the scintigrams. But seven of them had normal TBG concentrations in spite of the defects on the scintigrams. Out of 33 postoperative patients with liver metastasis, 28 (84%) had a raised TBG concentration. Only five (15.2%) had a normal TBG level. In 31 patients (93.9%) out of 33 with liver metastasis, a definite diagnosis was made on the basis of the liver scintigram. In 28 (90.3%) of these 31 people, the TBG concentration was higher than normal. Among 63 patients with liver tumors, both primary and metastatic, the test sensitivity for liver tumors was 92.1% (58/63) based on the accuracy of the liver scintigram. It was 79.4% (50/63) based on the TBG measurement. Why TBG increases to such an extent in spite of the euthyroid state remains unexplained. But it may be concluded that elevated TBG with positive liver scintigram furnishes a sensitive, fairly reliable, nonspecific tumor marker to determine liver tumors, especially in the case of liver metastasis. (orig.)

  8. Serum concentration of thyroxin and thyroid stimulating hormone in children suspected of thyroid dysfunction

    International Nuclear Information System (INIS)

    Elahi, S.; Syed, Z.; Rasheed, H.; Aman, Z.; Yasmeen, R.

    2010-01-01

    This study was planned to investigate serum concentration of free thyroxin (FT/sub 4/) and thyroid stimulating hormone (TSH) as well as thyroid dysfunctions in children attending CENUM, Mayo Hospital Lahore. A total of 227 children (131 female and 96 male) were selected for this study. Their age range was 1 to 12 years (mean 7.6 +- 3.4 years). 45 (19.8%) children had goiter with significantly more frequency in female as compared to male children (28.2% V s 8.3%; p<0.05). More than 70% of the children had F/sub 4/ and TSH within their respective normal ranges (euthyroid). Thyroid dysfunctions were detected in 11.0% children (7.5% hypothyroidism; 3.5% hyperthyroidism). Only the incidence of hyperthyroidism was significantly more in goiterous children. There was no significant difference in the incidence of hyperthyroidism but hypothyroidism was significant (p<0.05) more common in female children. (author)

  9. Total Laryngectomy Versus Larynx Preservation for T4a Larynx Cancer: Patterns of Care and Survival Outcomes

    International Nuclear Information System (INIS)

    Grover, Surbhi; Swisher-McClure, Samuel; Mitra, Nandita; Li, Jiaqi; Cohen, Roger B.; Ahn, Peter H.; Lukens, John N.; Chalian, Ara A.; Weinstein, Gregory S.; O'Malley, Bert W.; Lin, Alexander

    2015-01-01

    Purpose: To examine practice patterns and compare survival outcomes between total laryngectomy (TL) and larynx preservation chemoradiation (LP-CRT) in the setting of T4a larynx cancer, using a large national cancer registry. Methods and Materials: Using the National Cancer Database, we identified 969 patients from 2003 to 2006 with T4a squamous cell larynx cancer receiving definitive treatment with either initial TL plus adjuvant therapy or LP-CRT. Univariate and multivariable logistic regression were used to assess predictors of undergoing surgery. Survival outcomes were compared using Kaplan-Meier and propensity score–adjusted and inverse probability of treatment–weighted Cox proportional hazards methods. Sensitivity analyses were performed to account for unmeasured confounders. Results: A total of 616 patients (64%) received LP-CRT, and 353 (36%) received TL. On multivariable logistic regression, patients with adva