A modified direct insulin lodination for insulin radioreceptor assay in human erythrocytes

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Elnabrawie, F S; Megahed, Y M; Fahim, F A; Ahmed, A M [Middle Eastern Regional radioisotope center for Arab Countries biochemistry dept. Faculty of science Ain Shams university, cairo, (Egypt)

1995-10-01

A substitution of iodine in to the inulin molecule will easily lead to a decreased hormonal activity. Nevertheless it cannot be concluded without further investigation that one or several of the tyrosyl groups are directly involve in the degree of iodination and the loss activity has been demonstrated by many workers, (Frenkel-Conrat 1950, and de Zoeten and van Strik, 1961). On the basis of the Frenkel-Conrat experiments, lee 1957 suggested that a mono-substitution of iodine in two tyrosyl groups is possible without loss of biological activity. In general, iodination is easy to perform as usually carried out at room temperature at PH of 7.5 in a phosphate buffer medium (Megahed et al., 1976, 1979). Reaction between antigen and antibody in radioimmunoassay (RIA), immunoradiometric assay (IRMA) and radioreceptor assay (RRA), is detected by radiation emitted from a radioisotope incorporated into the antigen or antibody molecule. Ideally the radiolabelled molecule has an immunoreactivity identical to the natural molecule and this behaves in the same way as in the assay procedure. Oxidation of 125 I-iodide gives rise to the 125 I-iodination which in a mildly alkaline PH (7.5) reacts with the phenolic benzene ring of tyrosine and tyrosyl residues by a process of electrophilic attack.

A modified direct insulin lodination for insulin radioreceptor assay in human erythrocytes

International Nuclear Information System (INIS)

Elnabrawie, F.S.; Megahed, Y.M.; Fahim, F.A.; Ahmed, A.M.

1995-01-01

A substitution of iodine in to the inulin molecule will easily lead to a decreased hormonal activity. Nevertheless it cannot be concluded without further investigation that one or several of the tyrosyl groups are directly involve in the degree of iodination and the loss activity has been demonstrated by many workers, (Frenkel-Conrat 1950, and de Zoeten and van Strik, 1961). On the basis of the Frenkel-Conrat experiments, lee 1957 suggested that a mono-substitution of iodine in two tyrosyl groups is possible without loss of biological activity. In general, iodination is easy to perform as usually carried out at room temperature at PH of 7.5 in a phosphate buffer medium (Megahed et al., 1976, 1979). Reaction between antigen and antibody in radioimmunoassay (RIA), immunoradiometric assay (IRMA) and radioreceptor assay (RRA), is detected by radiation emitted from a radioisotope incorporated into the antigen or antibody molecule. Ideally the radiolabelled molecule has an immunoreactivity identical to the natural molecule and this behaves in the same way as in the assay procedure. Oxidation of 125 I-iodide gives rise to the 125 I-iodination which in a mildly alkaline PH (7.5) reacts with the phenolic benzene ring of tyrosine and tyrosyl residues by a process of electrophilic attack

A radioreceptor assay for measurement of plasma glucocorticoid binding activity

International Nuclear Information System (INIS)

Fan Jie

1990-01-01

A radioreceptor assay (RRA) for plasma glucocorticoid binding activity (GCBA) has been developed using glucocorticoid receptor in rat thymocytes. Unlike other assays for natural and certain synthetic corticosteroids, RRA measures the GCBA of all natural and synthetic GC in plasma. The range of standard curve was 0 ∼ 1.00 mg/L. The sensitivity was 0.01 mg/l. The recovery rate was 92.1%, and the intra and inter assay CV was 0.7% (n = 3) and 4.4% (n = 3) respectively. The level of corticosterone in 9 rat plasma samples was determined by RRA and CBG-isotope binding assay. There was a general correlation over a wide range between the values determined by the two assays (r = 0.95; P < 0.001). The measuring condition was described in detail

Studies on somatomedin A with special reference to its measurement by a radioreceptor assay

International Nuclear Information System (INIS)

Takano, K.

1975-01-01

A radioreceptor assay for somatomedin A was developed utilizing human placental membrane. This assay method is more sensitive and simpler than the chick bioassay and requires only 40μl of serum. It is not species specific. The level of somatomedin A in serum from different animals decrease with increased size of the animal species. (Auth.)

Development of a sensitive and specific radioreceptor assay for leukotriene B4

International Nuclear Information System (INIS)

Kohi, F.; Agrawal, D.K.; Cheng, J.B.; Bewtra, A.; Townley, R.G.; Olesch, J.W.

1988-01-01

To establish a simple and sensitive quantitation of leukotriene B 4 (LTB 4 ), they developed a radioreceptor assay (RRA) using a highly specific [ 3 H]leukotriene B 4 ([ 3 H]LTB 4 ) binding to a guinea pig spleen homogenate. The assay detected LTB 4 levels as low as 0.12 pmol per tube. 50% inhibition of bound [ 3 H]LTB 4 was obtained by 2.5 nM of unlabeled LTB 4 . [ 3 H]LTB 4 competition studies indicated that 20-hydroxy-LTB 4 was 8 times, 6 trans-LTB 4 was 640 times and 20-carboxy-LTB 4 was 1000 times less effective than LTB 4 . The peptide leukotrienes C 4 , D 4 and E 4 showed no effect on [ 3 H]LTB 4 binding. Recovery rates averaged 97% after ethanol extraction and evaporation of known amounts of LTB 4 . The intra-assay coefficients of variation for three samples were 2.4%, 7.2% and 8.4%, respectively. This assay was validated by measuring LTB 4 released from human granulocytes stimulated with calcium ionophore A23187. The LTB 4 level was maximal at 10 min and decreased rapidly after 15 min. This radioreceptor assay for leukotriene B 4 is highly sensitive and is comparable to the reported sensitivity by radioimmunoassay. The method is simpler and less expensive than other methods such as high pressure liquid chromatography and is suitable for routine measurement of leukotriene B 4

Application of hormone receptor assay for clinical chemistry

International Nuclear Information System (INIS)

Sato, Seiya

1978-01-01

A conception of hormone receptors was explained to understand radioreceptor assay (RRA), and various problems in the operation of this method were described mainly. The principle of RRA is the same as that of RIA and CPBA, and measured values by RRA resembled to those by bioassay more closely than those by RIA. However, the sensitivity of RRA was inferior to that of RIA. It was important in using this method especially for measurement of peptide hormone not to deactivate biological the base by radioactivation. As the significance of this method in clinical chemistry, it was mentioned that this method was one kind of experiment to observe the biological activity of hormones, and that properties analysis of receptors, studies on action mechanism, the structure and function of hormone, the pathological analysis of endocrine abnormalities, and the development of drugs and treatment methods for receptors may become possible by this method. The other usefulness of this method was also mentioned. (Kanao, N.)

Application of hormone receptor assay for clinical chemistry

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Sato, S [Kitasato Univ. Hospital, Sagamihara, Kanagawa (Japan)

1978-06-01

A conception of hormone receptors was explained to understand radioreceptor assay (RRA), and various problems in the operation of this method were described mainly. The principle of RRA is the same as that of RIA and CPBA, and measured values by RRA resembled to those by bioassay more closely than those by RIA. However, the sensitivity of RRA was inferior to that of RIA. It was important in using this method especially for measurement of peptide hormone not to deactivate biological the base by radioactivation. As the significance of this method in clinical chemistry, it was mentioned that this method was one kind of experiment to observe the biological activity of hormones, and that properties analysis of receptors, studies on action mechanism, the structure and function of hormone, the pathological analysis of endocrine abnormalities, and the development of drugs and treatment methods for receptors may become possible by this method. The other usefulness of this method was also mentioned.

Evaluation of a radioreceptor assay for TSH receptor autoantibodies

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Rootwelt, K.

1988-02-01

A commercial radioreceptor assay for TSH receptor autoantibodies (TRAb), based on solubilized porcine receptor and purified radio-iodinated bovine TSH, was tested in 264 subjects with a variety of thyroid disorders. The sensitivity of the assay for the detection of hyperthyroid Graves' disease was 91%. The assay specificity for Graves' disease was 95%. With the exception of one patient with Hashimoto's disease and one patient with de Quervain's subacute thyroiditis no subjects other than Graves' patients had detectable TRAb. Thus purely blocking TSII receptor autoantibodies were not detected with the assay. One female with thyroxine-treated idiopathic primary hypothyroidism who had given birth to two children with transiently elevated TSH, was found to have a circulating TSH-binding substance that resulted in an abnormally negative TRAb value, and highly discrepant results when TSH was measured with a double antibody TSH radioimmunoassay and an immunoradiometric assay. The TSH-binding substance was precipitated like a protein, but was not IgG. Similar findings have not previously been reported.

Measurement of rat serum FSH by radioreceptor assay and comparison with radioimmunoassay

International Nuclear Information System (INIS)

Minegishi, Takashi; Igarashi, Masao; Wakabayashi, Katsumi

1980-01-01

Follicle stimulating hormone (FSH) in rat serum is successfully measured by a radioreceptor assay system employing PMS-treated immature rat ovary. The non-specific inhibitory effect of serum was partially overcome by the addition of merthiolate to every component, while the residual effect was compensated for by using FSH-free serum which was prepared by passing the pooled female diestrous rat sera through an immunoadsorbent column packed with anti-ovine FSH-coupled Sepharose 4B. The assay system consisted of 100 μl of Tris-MgCl 2 -BSA or standard, 100 μl of FSH-free serum or sample, 100 μl of the receptor preparation and 100 μl of 125 I-FSH. The incubation was carried out for 4 hr at 37 0 C and 500 μl of cold Tris-MgCl 2 -BSA was used for the termination. Serum FSH could be measured within a range of 0.125 - 16 ng NIAMDD rat FSH I-3/tube. The mean within-assay coefficient of variation was 10.5%. The mean between-assay coefficient of variation was 11.0%. The assay values obtained by RRA showed a good correlation to those by RIA under the same physiological states of the animals. The ratio of the assay values, RRA/RIA, was found to change according to the sex and the physiological states, e.g. around 1.3 in normal males and 1.7 in orchiectomized animals and 2.21 in female rats. Serum FSH levels in female rats obtained by RRA and RIA changed almost in parallel until 20:00 (hr) of proestrous day, but after the first surge of serum FSH they were not parallel. These facts seem to indicate possible changes in the affinity of FSH with its receptor according to the state of animals and lead to the problem of the heterogeneity of FSH. (author)

Steroid receptor status in breast cancer: the roles of radioreceptor assay and immunohistochemistry

International Nuclear Information System (INIS)

Myint Aye Mu; Ch'ong

1997-01-01

A total of 24 cases of female breast cancer were reviewed, typed and graded based on the WHO classification. The steroid receptors (oestrogen and progesterone receptors) status was assessed using radio-receptor assay (RRA) and immunohistochemical (IH) method. The data showed that there were 21 cases of infiltrating ductal carcinoma of the breast and 3 cases of medullary carcinoma. The age of the patients ranged from 36 to 71 years and 4 patients were post-menopausal. The oestrogen receptor (ER) and progesteronc receptor (PR) status were analyzed by radio-receptor assay using 'H-oestradiol and 3 H-ORG respectively, and also by IH using immunoperoxidase detection assay (DAKO LSAB 2 Kit. Peroxidase K 677). Primary antibodies used were also procured from Dako Corp. and these were mouse anti-human ER and rabbit anti-human PR antibodies. On RRA analysis, 22 (95.7%) cases showed ER positivity (i.e. >20 fmol/mg of cytosol protien), and the ER content ranged from 16.64 to 297.8 fmovmg of cytosol protein. All cases showed PR positivity, and PR content ranged from 20.56 to 364 fmoumg of cytosol protein. A significant positive correlation was found between the ER content and PR content of tumour tissues (r = 0.7132, p<0.003). No significant association was found between ER content and menopausal status or histological grade IH showed that 10 of 24 cases (41.67%) showed ER positivity of which 8 were also PR positive. PR status was negative in all ER negative tissues. A decreasing trend in ER positivity was observed with worsening in histological grade (67% positivity in Grade 1, 50% positivity in Grade 11, and 33% positivity in Grade 111). ER and PR positivity occurred more frequently in pre-menopausal women. The results of this study showed that the result derived from IH method were found to have association with grade of tumour and confirmed findings by other workers. These findings revealed that although the quantitative data from radio-receptor assay for estimation of

Binding properties of beetal recombinant caprine growth hormone to ...

African Journals Online (AJOL)

SAM

2014-07-23

Jul 23, 2014 ... The aim of the study was to illustrate the radio-receptor assay of beetal recombinant caprine growth hormone (rcGH) ... interaction with microsomal membrane that shall be beneficial to study hormone receptor interactions of other Bovidae .... adding 1 ml of ice cold assay buffer, followed by 1 ml of 25% (w/v).

Radioreceptor assay of opioid peptides in selected canine brain regions

International Nuclear Information System (INIS)

Desiderio, D.M.; Takeshita, H.

1985-01-01

A radioreceptor assay using the opioid delta receptor-preferring ligand D- 2 ala, D- 5 leu leucine enkephalin ( 3 H-DADL) and the broader-specificity ligand 3 H-etorphine was used to measure five HPLC-purified neuropeptide fractions derived from the peptide-rich fraction of tissue homogenates of nine anatomical regions of the canine brain. The receptoractive peptides studied were methionine enkephalin, alpha-neo-endorphin, dynorphin 1-8, methionine enkephalin-Arg-Phe, and leucine enkephalin. These peptides derive from two larger precursors: proenkephalin A, which contains methionine enkephalin, leucine enkephalin, methionine enkephalin-Arg-Phe; and proenkephalin B, which contains alpha-neo-endorphin and dynorphin 1-8. Receptoractive peptides were measured in the peptide-rich fraction derived from homogenates of canine hypothalamus, pituitary, caudate nucleus, amygdala, hippocampus, mid-brain, thalamus, pons-medulla, and cortex

Radioreceptor assay of opioid peptides in selected canine brain regions

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Desiderio, D.M.; Takeshita, H.

1985-09-01

A radioreceptor assay using the opioid delta receptor-preferring ligand D-/sup 2/ala, D-/sup 5/leu leucine enkephalin (/sup 3/H-DADL) and the broader-specificity ligand /sup 3/H-etorphine was used to measure five HPLC-purified neuropeptide fractions derived from the peptide-rich fraction of tissue homogenates of nine anatomical regions of the canine brain. The receptoractive peptides studied were methionine enkephalin, alpha-neo-endorphin, dynorphin 1-8, methionine enkephalin-Arg-Phe, and leucine enkephalin. These peptides derive from two larger precursors: proenkephalin A, which contains methionine enkephalin, leucine enkephalin, methionine enkephalin-Arg-Phe; and proenkephalin B, which contains alpha-neo-endorphin and dynorphin 1-8. Receptoractive peptides were measured in the peptide-rich fraction derived from homogenates of canine hypothalamus, pituitary, caudate nucleus, amygdala, hippocampus, mid-brain, thalamus, pons-medulla, and cortex.

Gamma aminobutyric acid radioreceptor assay: a confirmatory quantitative assay for toxaphene in environmental and biological samples

International Nuclear Information System (INIS)

Saleh, M.A.; Blancato, J.N.

1993-01-01

Toxaphene is a complex mixture of polychlorinated monoterpenes, and was found to be acutely and chronically toxic to aquatic and wild life and posed a carcinogenic risk to humans before its ban in 1982. However, it is still found in the environment due to its relative persistence with an estimated half life time of about 10 years in soils. Toxaphenes neurotoxicity is attributed to a few isomers with a mode of action through binding to the chloride channel of the gamma-aminobutyric acid (GABA) receptor ionophore complex. [ 35 S] tertiary butylbicyclophosphorothionate (TBPS) with specific activity higher than 60 Ci/mmole has a high binding affinity to the same sites and is now commercially available and can be used to label the GABA receptor for the development of radioreceptor assay technique. The GABA receptor was prepared by a sequence of ultra centrifugation and dialysis of mammalian (rats, cows, catfish and goats) brain homogenates. The receptor is then labeled with [ 35 S] TBPS and the assay was conducted by measuring the displacement of radioactivity following incubation with the sample containing the analytes. The assay is fast, sensitive and requires very little or no sample preparation prior to the analysis. (Author)

Human epidermal growth factor: molecular forms and application of radioimmunoassay and radioreceptor assay

International Nuclear Information System (INIS)

Hirata, Y.; Orth, D.N.

1981-01-01

Epidermal growth factor (EGF), a 53 amino acid polypeptide, was first isolated by Cohen. EGF's growth-promoting activity is not limited to epidermal cells, but is expressed on a wide variety of tissues derived from a number of different species. Human EGF (hEGF) was isolated and subsequently purified from human urine. Unexpectedly, a close structural relationship was recognized between mEGF and human β-urogastrone. The authors recently developed both an homologous hEGF radioimmunoassay (RIA) and a radioreceptor assay (RRA) using a human placental membrane fraction. Using these assays, the molecular size of hEGF in human body fluids and tissues was evaluated, and partial characterization of a high molecular weight form of hEGF isolated from human urine was carried out. The concentrations of immunoreactive hEGF were also determined in human tissues and plasma after extraction either with cationic exchange chromatography or with immunoaffinity chromatography. (Auth.)

Radioreceptor assay for evaluation of the plasma glucocorticoid activity of natural and synthetic steroids in man

International Nuclear Information System (INIS)

Ballard, P.L.; Carter, J.P.; Graham, B.S.; Baxter, J.D.

1975-01-01

An assay for plasma glucocorticoid activity has been developed using specific glucocorticoid receptors. Unlike other assays for cortisol and certain synthetic corticosteroids, this radioreceptor assay measures the glucocorticoid activity of all natural and synthetic steroids. Steroids extracted from as little as 0.05 ml of plasma are incubated with 3 H-dexamethasone and cytosol receptors from cultured rat hepatoma cells. From 0.5 to 50 ng of cortisol are accurately detected. Glucocorticoid activities of adult plasmas determined by the assay correlate closely with corticoid levels obtained in the CBG-isotope and fluorometric assays. Other steroids are measured in proportion to both concentration and potency as glucocorticoids. Relative activities include: cortisol 100, dexamethasone 940, prednisolone 230, prednisone 3, estradiol 1 and androstenedione 1. A similar ranking of steroids was found using receptors from a human source (fetal lung). The assay has been useful in detecting glucocorticoid activity in unidentified medications and in measuring plasma glucocorticoid levels after administration of synthetic corticosteroids. (auth)

We don't look at hormones the way we used to

International Nuclear Information System (INIS)

Odell, W.D.

1977-01-01

Determination of hormones by means of bioassays, among others with the help of 131 iodine, in radioimmunoassays is studied within the frame of a general assay. The necessity of an exact knowledge of the physiology and pathophysiology of the hormones is pointed out. The poor purity of the hormones has disturbing effects on quantitive measurements. Application of radioimmunoassays increases the proofsensity by 200-500 times that obtained when applying bioassays. Assays with radioreceptors allow the purification of new hormones. Other positive characteristics of radioimmunoassays are described in detail. (AJ) [de

Hormone assay

International Nuclear Information System (INIS)

Eisentraut, A.M.

1977-01-01

An improved radioimmunoassay is described for measuring total triiodothyronine or total thyroxine levels in a sample of serum containing free endogenous thyroid hormone and endogenous thyroid hormone bound to thyroid hormone binding protein. The thyroid hormone is released from the protein by adding hydrochloric acid to the serum. The pH of the separated thyroid hormone and thyroid hormone binding protein is raised in the absence of a blocking agent without interference from the endogenous protein. 125 I-labelled thyroid hormone and thyroid hormone antibodies are added to the mixture, allowing the labelled and unlabelled thyroid hormone and the thyroid hormone antibody to bind competitively. This results in free thyroid hormone being separated from antibody bound thyroid hormone and thus the unknown quantity of thyroid hormone may be determined. A thyroid hormone test assay kit is described for this radioimmunoassay. It provides a 'single tube' assay which does not require blocking agents for endogenous protein interference nor an external solid phase sorption step for the separation of bound and free hormone after the competitive binding step; it also requires a minimum number of manipulative steps. Examples of the assay are given to illustrate the reproducibility, linearity and specificity of the assay. (UK)

Study of NSILA-s (nonsuppressible insulin-like activity soluble in acid ethanol) by a new radio-receptor assay

International Nuclear Information System (INIS)

Megyeri, K.

1977-01-01

The insulin-like activity nonsuppressible with insulin-antibodies (NSILA) accounts for 90% of the insulin activity of the blood plasma. A peptid, soluble in acid ethanol, was purified (NSILA-s) and specific NSILA-s receptors were found on the plasma membrane of liver cells. The specificity, kinetics, affinity and pH-optimum of NSILA-s receptors significantly differed from those of insulin-receptors. A new, highly specific radio-receptor assay was developed, applying 125 I NSILA-s and liver cell membranes or lymphocytes. By this means the NSILA-s concentration of blood plasma was determined under normal and pathological (hypoglycaemizing tumours, hypopituritarism, acromegaly, anorexia nervosa, etc.) conditions. It is concluded that, 90% of the NSILA-s concentration of blood plasma is bound. In cases of hypoglycaemizing tumours increased NSILA-s activity was demonstrated both in blood serum and in the extracts of the tumour-tissue. Pharmacological doses of growth hormon (GH) increased plasma NSILA-s concentration, however, in the case of stimulation- and inhibition-tests carried out in normal patients, no unambiguous relationship could be demonstrated between plasma GH- and NSILA-s-levels. (L.E.)

Measurement and characterization of neuronal cholecystokinin using a novel radioreceptor assay

International Nuclear Information System (INIS)

Beresford, I.J.M.; Clark, C.R.; Hughes, J.

1986-01-01

This study describes a novel radioreceptor assay (RRA) for cholecystokinin (CCK) which is the first to measure and characterize brain CCK using a technique not dependent on the generation of peptide antibodies. The CCK RRA utilizes the mouse cerebral cortex CCK receptor as the binding source and [ 125 I]BH-CCK-8 as the radiolabelled probe. CCK was extracted (90% methanol) from discrete brain regions (mouse) and quantified using the CCK RRA. The amygdala contained the highest concentration of CCK, followed by the olfactory bulbs and cerebral cortex. Moderate levels of CCK were found in the hippocampus, striatum and hypothalamus. Low levels of CCK were recorded in the pons, medulla and spinal cord, whilst no CCK was detected in the cerebellum. The molecular forms of CCK in amygdala, cerebral cortex and hypothalamus were characterized using RRA in conjunction with HPLC. CCK-8 was identified as the major molecular form with a smaller component attributable to CCK-4. (Auth.)

Radioreceptor assay for 1,25-dihydroxyvitamin D3 in serum and its application in the study of rachitis

International Nuclear Information System (INIS)

Shi Yuyuan; Zhang Peiyin; Li Yajuan

1988-01-01

A modifed radioreceptor assay for 1,25-(OH) 2 -D 3 (1,25-Dihydroxy vitamin D 3 , Dihydroxycholecalciferol, DHCC) in serum was established, which was proved to have high sensitivity, stability and accuracy, and was applied in patients with rachitis. The results showed that DHCC level in serum in rachictic patients was lower than that of the control. The detection rate of DHCC was obviously higher than that through symptoms, laboratory tests and X-ray examination in patients with rachitis. Therefore, this assay technique can be used as a sensitive indicator for diagnosis of rachitis. It was also found that DHCC level in mothers was cor-relative with their infants, so that assay for DHCC level in pregnant mothers has significance in prevention and treatment of rachitis in their infants

Binding properties of beetal recombinant caprine growth hormone to ...

African Journals Online (AJOL)

The aim of the study was to illustrate the radio-receptor assay of beetal recombinant caprine growth hormone (rcGH). Tracer (125I-rcGH) was prepared by iodinating beetal rcGH with iodine-125 and its biological activity was analyzed by rabbit anti-rcGH antibodies. Liver microsomal membranes of the Bovidae species ...

Evidence for alterations in luteinizing hormone secreted in rhesus monkeys with normal and inadequate luteal phases using radioreceptor and radioimmunoassay

Energy Technology Data Exchange (ETDEWEB)

Sakai, C.N.; Channing, C.P.

1979-05-01

A radioreceptor assay (RRA) using porcine granulosa cells and (/sup 125/I)hCG was developed and validated for the measurement of LH or CG. The RRA was used in conjunction with a heterologous RIA employing antiserum against ovine LH and (/sup 125/I)ovine LH (RIA) to measure serum LH in the rhesus monkey throughout the menstrual cycle. Discrepancies were found in the measurement of serum LH using RRA and RIA. Measurements of serum LH using RIA were consistently higher than the measurements of serum LH using RRA in serum from adult intact female and male monkeys and hypophysectomized, ovariectomized, and pregnant monkeys.

The measurement of TSH-receptor autoantibodies in human serum by radioreceptor assay

International Nuclear Information System (INIS)

Truong, T.X.

2002-01-01

TSH receptor autoantibodies (TRAB) are valuable in Graves' disease with a sensitivity of 85% and a specificity of 80%. Autoantibodies levels decrease progressively with antithyroid drugs treatment or after thyroidectomy. The predictive value of the level of TSH receptor autoantibodies is diversely appreciated. Nevertheless, the vast majority of the studies agrees on the fact that high levels of TSH receptor autoantibodies predict a relapse. The feto-placental transfer of these antibodies could explain congenital hyperthyroidism of newborns from mother affected by Graves' disease. These antibodies are present in certain cases of Hashimoto thyroiditis, subacute thyroiditis or silent thyroiditis in phase of thyrotoxicosis. In Vietnam, first time we have researched determination of TRAB levels in the non disease and the Graves' disease, after treatment of antithyroid drugs and after thyroidectomy. We imported TRAB - Kit from CIS bio international France. The principle of Radioreceptor assay (RRA ) is following: TR - Ab kit utilizes a principle of competition between TSH receptor autoantibodies present in the sample and bovine TSH radiolabelled with 125 -I, facing a fixed and limited amount of soluble porcine TSH receptors. The more TSH receptor autoantibodies are present in the sample, the less 125 -I- TSH is bound to the soluble TSH receptors. Free and bound fractions are separated in adding PEG solution followed by a centrifugation. Results are calculated from a calibration curve (U/l). The samples were counted by the multi crystal gamma counter Oakfield which was supplied from IAEA (Years 2000). This is the first study in Vietnam, the concentration of TSH receptor autoantibodies (TRAB) was determined by radioreceptor assay (RRA) on 30 normal subjects and 30 Grave's disease subjects. The normal range is 1,4 □ 0.6 U/l. Max of normal is 2.99U/l. Min of normal is 3.38U/l .There are 11 males and 29 females with age from 15 to 50 years old. Mean of Graves' disease is

Insulin radioreceptor assay on murine splenic leukocytes and peripheral erythrocytes

International Nuclear Information System (INIS)

Shimizu, F.; Kahn, R.

1982-01-01

Insulin radioreceptor assays were developed using splenic leukocytes and peripheral erythrocytes from individual mice. Splenic leukocytes were prepared using an NH 4 Cl buffer which did not alter insulin binding, but gave much higher yields than density gradient methods. Mouse erythrocytes were isolated from heparinized blood by three passages over a Boyum gradient, and a similar buffer was used to separate cells from free [ 125 I]iodoinsulin at the end of the binding incubation. Insulin binding to both splenic leukocytes and peripheral erythrocytes had typical pH, temperature, and time dependencies, and increased linearly with an increased number of cells. Optimal conditions for the splenic leukocytes (6 x 10 7 /ml) consisted of incubation with [ 125 I]iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.0. In cells from 20 individual mice, the specific [ 125 I]iodoinsulin binding was 2.6 +/- 0.1% (SEM), and nonspecific binding was 0.3 +/- 0.04% (10.6% of total binding). Erythrocytes (2.8 x 10 9 /ml) were incubated with [ 125 ]iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.2. In cells from 25 individual mice, the specific [ 125 I]iodoinsulin binding was 4.5 +/- 0.2%, and nonspecific binding was 0.7 +/- 0.03% (13.6% of total binding). In both splenic leukocytes and peripheral erythrocytes, analysis of equilibrium binding data produced curvilinear Scatchard plots with approximately 3500 binding sites/leukocyte and 20 binding sites/erythrocyte. These data demonstrate that adequate numbers of splenic leukocytes and peripheral erythrocytes can be obtained from individual mice to study insulin binding in a precise and reproducible manner

Radioimmunoassay for somatomedin C: comparison with radioreceptor assay in patients with growth-hormone disorders, hypothyroidism, and renal failure

Energy Technology Data Exchange (ETDEWEB)

Baxter, R.C.; Brown, A.S.; Turtle, J.R.

1982-03-01

An antiserum (Tr4) was raised in rabbits against a basic somatomedin C-like peptide preparation. Using high-immunoreactivity somatomedin C tracer, we compared the performance of radioimmunoassays in which we used the Tr4 antiserum distributed by the National Pituitary Agency (NPA) with that of the human placental-membrane somatomedin radioreceptor asay (RRA). In their cross reactivity towards various somatomedin-like and unrelated peptides, the two radioimmunoassay methods were almost identical, although NPA antiserum, with about fourfold higher titer than Tr4 antiserum, showed a slightly greater sensitivity for most peptides tested. Radioimmunoassay of acid-ethanol-extracted plasma samples from normal persons and acromegalic, hypopituitary, hypothyroid, and renal-failure patients revealed no analytical differences between the antisera (for 122 samples, r = 0.979 between methods). Somatomedin values for acromegalic and hypopituitary samples showed no overlap with normals. Values for hypothyroid and pre-dialysis renal-failure samples were significantly lower than normal. By comparison, the RRA showed greater cross reactivity towards some somatomedin-like peptides and gave significantly lower values than radioimmunoassay for acromegalic and hypothyroid plasma extracts, and significantly higher values for hypopituitary and renal-failure samples. We conclude that the radioimmunoassay methods clearly are of greater diagnostic value than RRA for clinical somatomedin measurement.

Radioreceptor assay for TBII in the spectrum of thyroid stimulating immunoglobulins

Energy Technology Data Exchange (ETDEWEB)

Bliddal, H.

1986-01-01

Thyroid stimulating immunoglobulins have been measured by several different methods among which the radioreceptor assay for TBII has been mostly employed. This technique is review in detail and it is concluded that the present method has the advantage of a larger stability aquired by the use of a purified plasma membrane fraction produced from autopsy material. TBII has been found in 60 to 80 percent in untreated Graves' disease while the percentage of positive patients decreases after any kind of treatment. Thus, TBII descreases during long term antithyroid treatment and by the end of such treatment TBII has a certain prognostic value. In the present study TBII was correlated to several other methods of measurement, primarily with the thyroid adenylate cyclase stimulating antibodies. In Graves's disease a general correlation was found with significant differences in TBII and TSAb activity in some cases. In contrast, a dissociation between two tests was often found in Hashimoto's thyroiditis and several other diseases with a low occurence of these antibodies, e.g. IDDM. Based on the present results it is concluded that thyroid stimulating immunoglobulins are heterogenous and probably polyclonal antibodies directed against several different epitopes on the TSH receptor with different affinity for the binding side of TSH. An activation in vitro by adenylate cyclase is apparently possible by-passing this binding side, and in some sera antibodies have been described which block the adenylate cyclase in vitro without affecting the binding of TSH. It is concluded that these antibodies are a major factor in the pathogenesis of thyrotoxicosis in Graves' disease, while differences in expression and affinity of antibodies against the TSH receptor may explain the lack of clinical correlation in other diseases. 193 refs.

Thyroid-stimulating immunoglobulins in Hashimoto's thyroiditis measured by radioreceptor assay and adenylate cyclase stimulation and their relationship to HLA-D alleles

International Nuclear Information System (INIS)

Bliddal, H.; Bech, K.; Feldt-Rasmussen, U.; Thomsen, M.; Ryder, L.P.; Hansen, J.M.; Siersbaek-Nielsen, K.; Friis, T.

1982-01-01

The relationship between thyroid-stimulating immunoglobulins, measured by both radioreceptor assay and adenylate cyclase stimulation, and the HLA alleles was studied in 41 patients with Hashimoto's thyroiditis. TSH binding-inhibiting immunoglobulins (TBII) were detected in 9 (22%) patients, and human thyroid adenylate cyclase-stimulating immunoglobulins (HTACS) were found in 21 (51%) patients. Only 2 patients were positive in both assays, and an inverse relationship was observed between TBII and HTACS. In the 21 HTACS-positive patients, HLA-Dw5 was found in 1 subject, compared to 8 of the 20 HTACS-negative patients (P < 0.01), while 4 of the 9 TBII-positive patients had HLA-Dw5 compared to 5 of the 32 TBII-negative subjects (P = 0.09).No significant relations were observed between the presence of HTACS or TBII and HLA-Dw3 or HLA-B8. It is concluded that TBII and HTACS are produced independently in Hashimoto's thyroiditis, and that the production of these autoantibodies seems to be related to the HLA-D region in this disease

Progress of measurement of hormones

International Nuclear Information System (INIS)

Ohsawa, Nakaaki

1977-01-01

Description was made as to an outline of the theory of radioreceptor assay (RRA) in which hormone receptor was used as specific binding protein, as same as the theory of RIA, and as to its practical use. Meaning of RRA for measurement of hormones in consideration of the site of immunological and biological activation and meaning of difference in measurement values between this method and in RIA in the same materials, were mentioned, and effectiveness of use of this method together with RIA was described. Detection of receptor site, analysis of binding specificity, and numerical calculation were mentioned as receptor analysis by this method. As practical use of these functions, arrangement mechanism of receptor, and analysis of abnormality were mentioned. Especially, analysis of testicular feminization syndrome, insulinresistenter diabetes, hyperthyroidism, and myasthenia gravis, and relationship between these diseases and autoimmune diseases were described, and clinical meaning of this method in internal medicine and surgery was mentioned. (Kanao, N.)

Quality control of insulin radioreceptor assay for human erythrocytes. Effect of ageing of mono-125I-Tyr-A14-insulin preparation

International Nuclear Information System (INIS)

Marttinen, A.; Pasternack, A.; Koivula, T.; Jokela, H.; Lehtinen, M.

1984-01-01

The quality control of insulin radioreceptor assay for human erythrocytes is based on the storage of erythrocyte preparations in Hepes buffer of pH 8.0, containing 10 g/l of albumin and 20 mmol/l of glucose. The change of erythrocytes into spherocytes and crenated cells reduces the apparent number of insulin receptors in a relatively constant way by less than 8% a week after 10 days of storage. At the same time the dissociation constants of the insulin-receptor complex increase rapidly. Thus the use of a preparation must be limited to controlling the determination of the insulin binding sites of erythrocytes, and not to the measurement of the affinities of the receptors. When mono- 125 I-Tyr-A14-insulin gets old, a slow decrease in the insulin binding sites can be measured, but the dissociation constants of the insulin receptor complex are not affected. (author)

Thyroid-stimulating immunoglobulins in Hashimoto's thyroiditis measured by radioreceptor assay and adenylate cyclase stimulation and their relationship to HLA-D alleles

Energy Technology Data Exchange (ETDEWEB)

Bliddal, H. (Frederiksberg Hospital, Copenhagen, Denmark); Bech, K.; Feldt-Rasmussen, U.; Thomsen, M.; Ryder, L.P.; Hansen, J.M.; Siersbaek-Nielsen, K.; Friis, T.

1982-11-01

The relationship between thyroid-stimulating immunoglobulins, measured by both radioreceptor assay and adenylate cyclase stimulation, and the HLA alleles was studied in 41 patients with Hashimoto's thyroiditis. TSH binding-inhibiting immunoglobulins (TBII) were detected in 9 (22%) patients, and human thyroid adenylate cyclase-stimulating immunoglobulins (HTACS) were found in 21 (51%) patients. Only 2 patients were positive in both assays, and an inverse relationship was observed between TBII and HTACS. In the 21 HTACS-positive patients, HLA-Dw5 was found in 1 subject, compared to 8 of the 20 HTACS-negative patients (P < 0.01), while 4 of the 9 TBII-positive patients had HLA-Dw5 compared to 5 of the 32 TBII-negative subjects (P = 0.09).No significant relations were observed between the presence of HTACS or TBII and HLA-Dw3 or HLA-B8. It is concluded that TBII and HTACS are produced independently in Hashimoto's thyroiditis, and that the production of these autoantibodies seems to be related to the HLA-D region in this disease.

Quality control of insulin radioreceptor assay for human erythrocytes. Effect of ageing of mono-/sup 125/I-Tyr-A14-insulin preparation

Energy Technology Data Exchange (ETDEWEB)

Marttinen, A; Pasternack, A [Tampere Univ. (Finland). Dept. of Clinical Sciences; Koivula, T; Jokela, H; Lehtinen, M [Tampere Univ. Central Hospital (Finland). Dept. of Clinical Chemistry

1984-09-01

The quality control of insulin radioreceptor assay for human erythrocytes is based on the storage of erythrocyte preparations in Hepes buffer of pH 8.0, containing 10 g/l of albumin and 20 mmol/l of glucose. The change of erythrocytes into spherocytes and crenated cells reduces the apparent number of insulin receptors in a relatively constant way by less than 8% a week after 10 days of storage. At the same time the dissociation constants of the insulin-receptor complex increase rapidly. Thus the use of a preparation must be limited to controlling the determination of the insulin binding sites of erythrocytes, and not to the measurement of the affinities of the receptors. When mono-/sup 125/I-Tyr-A14-insulin gets old, a slow decrease in the insulin binding sites can be measured, but the dissociation constants of the insulin receptor complex are not affected.

Decapeptides as effective agonists from L-amino acids biologically equivalent to the luteinizing hormone-releasing hormone

International Nuclear Information System (INIS)

Folkers, K.; Bowers, C.Y.; Tang, P.L.; Kubota, M.

1986-01-01

Apparently, no agonist has been found that is comparable in potency to the luteinizing hormone-releasing hormone (LHRH) for release of LH and follicle-stimulating hormone (FSH) without substitutions with unnatural or D forms of natural amino acids. Of 139 known agonist analogs of LHRH, two were active in the range of 65%. The four LHRHs known to occur in nature involve a total of six amino acids (Tyr, His, Leu, Trp, Arg, Gln) in positions 5, 7, and 8. There are 16 possible peptides with these six amino acids in positions 5, 7, and 8, of which 4 are the known LHRHs, and 2 more were synthesized. The authors have synthesized the 10 new peptides and assayed 11 in vivo and in vitro, and they found not only 1 but a total of 5 that have activity equivalent to or greater than that of LHRH for the release of LH and/or FSH under at least one assay condition. These five are as follows: [His 5 ,Trp 7 ,Gln 8 ]LHRH; [His 5 ,Trp 7 ,Leu 8 ]LHRH; [His 5 ,Trp 7 ]LHRH; [Trp 7 ]LHRH; [His 5 ]LHRH. These structures are a basis for the design of antagonists without Arg 8 toward avoiding histamine release. Complete inhibition of LH and FSH release in vivo may be induced by joint use of Arg 8 and Gln 8 or Leu 8 antagonists. These potent agonists, related to LHRH, may be therapeutically useful in disorders of reproduction, the central nervous system, and for the control of hormone-dependent carcinomas. Radioreceptor assays and radioimmunoassays were utilized

Study of change of sex hormone receptors in diabetic impotent patients

International Nuclear Information System (INIS)

Zhang Yong; Chen Weizhen; Zhang Zikang; Hu Xiaoke

2002-01-01

To study the relationship between diabetic impotence and sex hormones as well as sex hormone receptors. 32 diabetic impotent patients, 32 diabetic patients with normal sex function, 32 impotent patients without diabetes, and 40 healthy men were enrolled. The plasma sex hormone levels were examined by radioimmunoassay, and sex hormone receptors in white blood cells by radioreceptor assay. Compared with healthy men and impotent patients without diabetes, PRL levels in both diabetic impotent patients and diabetic patients with normal sex function increased markedly, T and AR levels decreased, and the ratio of E 2 /T and ER/AR increased. Compared with diabetic patients with normal sex function, while there was no significant difference in PRL, T and E 2 /T ratio, the AR level of diabetic impotent patients further decreased, and the ER/AR ratio further increased. Negative correlation was found between age and AR as well as T. The decline of AR and the increase of ER/AR ratio might be one main cause of diabetic impotence. And the decline of T and AR might be an important cause of the increase of diabetic impotence incidence with age

A radioreceptor assay of luteinizing hormone-releasing hormone receptor and characterization of LHRH binding to pituitary receptors in Shao duck

International Nuclear Information System (INIS)

Yang Peixin; Wu Meiwen; Chen Ziyuan

2000-01-01

The properties of Shao duck pituitary luteinizing hormone-releasing hormone (LHRH) receptors were analyzed in pituitary membrane preparation and isolated pituitary cells prepared by enzymatic dispersion with collagenase and trypsin, by using a super-agonist analog of (D-Lys 6 ) LHRH. High binding of 125 I-(D-Lys 6 ) LHRH to 10 6 cultured cells of Shao duck was observed after a 90 minute incubation at 4 degree C, while binding was significantly reduced after a 24h incubation. Binding of the radioligand was a function of tissue concentration of Shao duck pituitary membrane preparation, with a positive correlation over the range of 1-2 pituitary per-tube. Specific binding for 125 I-(D-Lys 6 ) LHRH increased with the increase in the amount of 125 I-(D-Lys 6 ) LHRH. The Scatchard analysis of data revealed a linear relationship between the amount of specific binding and the ratio of specific binding to free 1 '2 5 I(D-Lys 6 )LHRH, indicating a single class of high affinity sites. Equilibrium dissociation constant (Kd) was 0.34 nM in pituitary membrane preparation and 0.43 nM in isolated pituitary cells. Both Kd values were near and the maximum binding capacity (B max ) was great in isolated cells, suggesting no significant loss of the LHRH receptor population caused by the enzymatic procedure employed for cell dispersion in the present study. Addition of 9D-Lys 6 ) LHRH displaced bound 125 I-(D-Lys 6 ) LHRH. These results demonstrated the presence and provided characterization of LHRH receptors in Shao duck pituitary

Development and clinical application of a radioimmunoassay for circulating 1,25 and 25,26-dihydroxycholecalciferol in man

International Nuclear Information System (INIS)

O'Riordan, J.L.H.; Hendy, G.N.; Fraher, L.J.; Papapoulos, S.E.; Sandler, L.M.; Clemens, T.L.

1979-01-01

Recent interest is centred on the development of improved assays for 1,25-dihydroxycholecalciferol (1,25-(OH) 2 D 3 ) the hormonal form of vitamin D. Because radioimmunoassays have been successful when applied to the measurement of steroid hormones it seemed reasonable to use this approach to assay 1,25-(OH) 2 D 3 . These techniques have now been developed and applied to clinical studies. Clearly, the radioimmunoassay using tritium as label, is proving to be a versatile tool in the clinical study of the production and disposition of the hydroxylated vitamin D metabolites. This technique has a distinct practical advantage over existing radioreceptor assays in that antibodies provide a continuous supply of stable binding reagent whereas radioreceptor assays require preparation of intestinal binding protein from vitamin D deficient chickens. Moreover, with the radioimmunoasay approach there is considerable potential for further development. For example, by immunizing more animals with the same or different immunogens it may be possible to produce antisera with even higher affinity and with greatest structural specificity. These possibilities are now being investigated. (Auth.)

Assay-specific decision limits for two new automated parathyroid hormone and 25-hydroxyvitamin D assays.

Science.gov (United States)

Souberbielle, Jean-Claude; Fayol, Véronique; Sault, Corinne; Lawson-Body, Ethel; Kahan, André; Cormier, Catherine

2005-02-01

The recent development of nonradioactive automated assays for serum parathyroid hormone (PTH) and 25-hydroxyvitamin D (25OHD) has made measurement of these two hormones possible in many laboratories. In this study, we compared two new assays for PTH and 25OHD adapted on an automated analyzer, the LIAISON, with two manual immunoassays used worldwide. We studied 228 osteoporotic patients, 927 healthy individuals, 38 patients with primary hyperparathyroidism, and 167 hemodialyzed patients. Serum PTH was measured with the Allegro and the LIAISON assays, and 25OHD was measured with DiaSorin RIA and the LIAISON assay. Regression analysis was used to calculate decision thresholds for the LIAISON assays that were equivalent to those of the Allegro PTH and DiaSorin 25OHD assays. The 25OHD concentrations obtained with the LIAISON assay and the RIA in osteoporotic patients were well correlated (r = 0.83; P 50 nmol/L as eligible for the reference population for the LIAISON PTH assay. In this group, the 3rd-97th percentile interval for LIAISON PTH was 3-51 ng/L. Considering upper reference limits of 46 and 51 ng/L for the Allegro and LIAISON assays, respectively, the frequency of above-normal PTH concentrations in patients with primary hyperparathyroidism was similar in both assays. Regression analysis between serum PTH measured by the Allegro and LIAISON assays in 167 hemodialyzed patients and the corresponding Bland-Altman analysis of these data suggest that the LIAISON PTH assay tends to read higher than the Allegro assay at low concentrations but lower at high concentrations (>300 ng/L). Because clinical decision limits for both PTH and 25OHD should be assay specific, we propose equivalences between these assays and two manual assays used worldwide. These assay-specific decision limits should help potential users of the LIAISON PTH and 25OHD assays.

Heterogeneity of protein hormones

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Rosselin, G; Bataille, D; Laburthe, M; Duran-Garcia, S [Institut National de la Sante et de la Recherche Medicale (INSERM), Hopital Saint-Antoine, 75 - Paris (France)

1975-12-01

Radioimmunoassay measures antigenic determinants of hormonal molecules in the plasmas and tissues. These estimations carried out after fractionation in biological fluids, have revealed several immunological forms of the same hormone. The main problem is in the relationship of the various immunoreactive forms to the same hormonal sequence. The similar immunoreactive forms of high molecular weight usually have low biological activity and suggest the presence of prohormone; the suggestion of prohormonal nature depends on the chronology of the incorporation of labelled leucine and enzymatic transformation of prohormone with low biological into active hormone. The forms with high molecular weight and similar immunological activity may be of another nature. Thus, it has been shown that the biosynthetic nature of a compound such as big big insulin in the rat is doubtful owing to the absence of specific incorporation of labelled leucine into the immunoprecipitate of this fraction. The significance of low molecular weight form is still little known. An example of these forms is supplied by the existence of an alpha sub-unit of gonadotrophin present in the plasma of menopausal women. The interest of analytical methods by radio-receptor, simulation of cyclase activity in the identification of biological activity of immunoreactive forms, is discussed in relation to immunological forms ofenteroglucagon. An unusual aspect of the evolutive and adaptative character of hormonal heterogeneity is given by the gastro-intestinal hormones.

Measurement of thyroid-stimulating autoantibodies using a radioreceptor-assay (TRAK-assay)

International Nuclear Information System (INIS)

Becker, W.; Reiners, C.; Boerner, W.

1983-01-01

Autoantibodes against TSH-receptors were determined with a new radioreceptorassay (TRAK-assay) in 37 patients with untreated toxic diffus goitre and in 73 patients with non immunogenic thyroid diseases (41 healthy controls, respectively patients with euthyroid diffus or nodular goitres as well as 32 patients with toxic nodular goitre). The upper limit of normal is a TRAK-Titer of 20% without considerable fluctuations during titers in follow-up. According to this preliminary results it seems to be recommendable to treat patients with TRAK-titer F 20% (expected risk of relapse) primarily by operation or radioiodine. (orig.) [de

Hormone action. Part I. Peptide hormones

International Nuclear Information System (INIS)

Birnbaumer, L.; O'Malley, B.W.

1985-01-01

The major sections of this book on the hormonal action of peptide hormones cover receptor assays, identification of receptor proteins, methods for identification of internalized hormones and hormone receptors, preparation of hormonally responsive cells and cell hybrids, purification of membrane receptors and related techniques, assays of hormonal effects and related functions, and antibodies in hormone action

Persistent Graves' hyperthyroidism despite rapid negative conversion of thyroid-stimulating hormone-binding inhibitory immunoglobulin assay results: a case report.

Science.gov (United States)

Ohara, Nobumasa; Kaneko, Masanori; Kitazawa, Masaru; Uemura, Yasuyuki; Minagawa, Shinichi; Miyakoshi, Masashi; Kaneko, Kenzo; Kamoi, Kyuzi

2017-02-06

Graves' disease is an autoimmune thyroid disorder characterized by hyperthyroidism, and patients exhibit thyroid-stimulating hormone receptor antibody. The major methods of measuring circulating thyroid-stimulating hormone receptor antibody include the thyroid-stimulating hormone-binding inhibitory immunoglobulin assays. Although the diagnostic accuracy of these assays has been improved, a minority of patients with Graves' disease test negative even on second-generation and third-generation thyroid-stimulating hormone-binding inhibitory immunoglobulins. We report a rare case of a thyroid-stimulating hormone-binding inhibitory immunoglobulin-positive patient with Graves' disease who showed rapid lowering of thyroid-stimulating hormone-binding inhibitory immunoglobulin levels following administration of the anti-thyroid drug thiamazole, but still experienced Graves' hyperthyroidism. A 45-year-old Japanese man presented with severe hyperthyroidism (serum free triiodothyronine >25.0 pg/mL; reference range 1.7 to 3.7 pg/mL) and tested weakly positive for thyroid-stimulating hormone-binding inhibitory immunoglobulins on second-generation tests (2.1 IU/L; reference range hyperthyroidism for more than 8 years, requiring 15 mg/day of thiamazole to correct. During that period, he tested negative on all first-generation, second-generation, and third-generation thyroid-stimulating hormone-binding inhibitory immunoglobulin assays, but thyroid scintigraphy revealed diffuse and increased uptake, and thyroid ultrasound and color flow Doppler imaging showed typical findings of Graves' hyperthyroidism. The possible explanations for serial changes in the thyroid-stimulating hormone-binding inhibitory immunoglobulin results in our patient include the presence of thyroid-stimulating hormone receptor antibody, which is bioactive but less reactive on thyroid-stimulating hormone-binding inhibitory immunoglobulin assays, or the effect of reduced levels of circulating thyroid

Studies on insulin receptor, 1

International Nuclear Information System (INIS)

Sakai, Yukio

1979-01-01

The present study was designed for the purpose of establishing a method of insulin radioreceptor assay using plasma membranes of guinea pigs as receptor sites. The results obtained are as follows: 1) Insulin receptor in the renal plasma membranes of guinea pigs showed a significantly high affinity to porcine insulin compared with that in the plasma membranes of guinea pig liver or rat kidney and liver. 2) In the insulin radioreceptor assay, an optimum condition was observed by the incubation at 4 0 C for 24 - 48 hours with 100 μg membrane protein of guinea pig kidney and 0.08 ng of 125 I-insulin. This assay method was specific for insulin and showed an accurate biological activity of insulin. 3) The recovery rate of insulin radioreceptor assay was 98.4% and dilution check up to 16 times did not influence on the result. An average of coefficient variation was 3.92% within assay. All of these results indicated the method to be satisfactory. 4) Glucose induced insulin release by perfusion method in isolated Langerhans islets of rats showed an identical pattern of reaction curves between radioreceptor assay and radioimmunoassay, although the values of radioreceptor assay was slightly low. 5) Insulin free serum produced by ultra filtration method was added to the standard assay medium. By this procedure, direct measurement of human serum by radioreceptor assay became possible. 6) The value of human serum insulin receptor binding activity by the radioreceptor assay showed a high correlation with that of insulin radioimmunoassay in sera of normal, borderline or diabetic type defined by glucose tolerance test. (author)

Association of Biotin Ingestion With Performance of Hormone and Nonhormone Assays in Healthy Adults.

Science.gov (United States)

Li, Danni; Radulescu, Angela; Shrestha, Rupendra T; Root, Matthew; Karger, Amy B; Killeen, Anthony A; Hodges, James S; Fan, Shu-Ling; Ferguson, Angela; Garg, Uttam; Sokoll, Lori J; Burmeister, Lynn A

2017-09-26

Biotinylated antibodies and analogues, with their strong binding to streptavidin, are used in many clinical laboratory tests. Excess biotin in blood due to supplemental biotin ingestion may affect biotin-streptavidin binding, leading to potential clinical misinterpretation. However, the degree of interference remains undefined in healthy adults. To assess performance of specific biotinylated immunoassays after 7 days of ingesting 10 mg/d of biotin, a dose common in over-the-counter supplements for healthy adults. Nonrandomized crossover trial involving 6 healthy adults who were treated at an academic medical center research laboratory. Administration of 10 mg/d of biotin supplementation for 7 days. Analyte concentrations were compared with baseline (day 0) measures on the seventh day of biotin treatment and 7 days after treatment had stopped (day 14). The 11 analytes included 9 hormones (ie, thyroid-stimulating hormone, total thyroxine, total triiodothyronine, free thyroxine, free triiodothyronine, parathyroid hormone, prolactin, N-terminal pro-brain natriuretic peptide, 25-hydroxyvitamin D) and 2 nonhormones (prostate-specific antigen and ferritin). A total of 37 immunoassays for the 11 analytes were evaluated on 4 diagnostic systems, including 23 assays that incorporated biotin and streptavidin components and 14 assays that did not include biotin and streptavidin components and served as negative controls. Among the 2 women and 4 men (mean age, 38 years [range, 31-45 years]) who took 10 mg/d of biotin for 7 days, biotin ingestion-associated interference was found in 9 of the 23 (39%) biotinylated assays compared with none of the 14 nonbiotinylated assays (P = .007). Results from 5 of 8 biotinylated (63%) competitive immunoassays tested falsely high and results from 4 out of 15 (27%) biotinylated sandwich immunoassays tested falsely low. In this preliminary study of 6 healthy adult participants and 11 hormone and nonhormone analytes measured by 37 immunoassays

Heterophilic antibody interference affecting multiple hormone assays: Is it due to rheumatoid factor?

Science.gov (United States)

Mongolu, Shiva; Armston, Annie E; Mozley, Erin; Nasruddin, Azraai

2016-01-01

Assay interference with heterophilic antibodies has been well described in literature. Rheumatoid factor is known to cause similar interference leading to falsely elevated hormone levels when measured by immunometric methods like enzyme-linked immunosorbent assay (ELISA) or multiplex immunoasays (MIA). We report a case of a 60-year-old male patient with a history of rheumatoid arthritis referred to our endocrine clinic for investigation of hypogonadism and was found to have high serum levels of LH, FSH, SHBG, Prolactin, HCG and TSH. We suspected assay interference and further tests were performed. We used Heteroblock tubes and PEG precipitation to eliminate the interference and the hormone levels post treatment were in the normal range. We believe the interference was caused by high serum levels of rheumatoid factor. Although he was treated with thyroxine for 3 years, we believe he may have been treated inappropriately as his Free T4 level was always normal despite high TSH due to assay interference. Our case illustrates the phenomenon of heterophilic antibody interference likely due to high levels of rheumatoid factor. It is essential for clinicians and endocrinologists in particular to be aware of this possibility when making treatment decisions in these groups of patients.

Heterogeneity of pituitary and plasma prolactin in man: decreased affinity of big prolactin in a radioreceptor assay and evidence for its secretion

International Nuclear Information System (INIS)

Garnier, P.E.; Aubert, M.L.; Kaplan, S.L.; Grumbach, M.M.

1978-01-01

Molecular heterogeneity of immunoreactive human PRL (IR-hPRL) plasma was assessed by exclusion chromatography in blood from 4 normal adults, 3 newborn infants, 2 late gestational women, 3 patients with primary hypothyroidism and high PRL levels, 2 with functional hyperprolactinemia, 3 with acromegaly, and 10 with PRL-secreting tumors. Three forms of PRL were detected: big-big hPRL, big hPRL, and little hPRL. In normal subjects, the proportion of big-big, big, and little hPRL components was 5.1%, 9.1%, and 85.8%, respectively, without change in the distribution after TRF stimulation. In 8 of 10 patients with PRL-secreting tumors, we detected a significantly higher proportion of big PRL. In 2 additional patients with prolactinomas, the proportion of big PRL was much higher. In 3 of 10 patients, the molecular heterogeneity of the tumor PRL was similar to that in plasma. In 1 acromegalic, there was a very high proportion of big-big hPRL. The PRL fractions were tested in a radioreceptor assay (RRA) using membranes from rabbit mammary gland. Big PRL was much less active than little PRL in the RRA. The fractions were rechromatographed after storage. Big PRL partially distributed as little or big-big PRL, while little PRL remained unchanged. Big-big PRL from tumor extract partially converted into big and little PRL. The big PRL obtained by rechromatography had low activity in the RRA. These observations suggest at least part of the receptor activity of big PRL may arise from generation of or contamination by little PRL. The decreased binding affinity of big PRL in the RRA also indicates that big PRL has little, if any, biological activity. The evidence suggests big PRL is a native PRL dimer linked by intermolecular disulfide bonds which arises in the lactotrope as a postsynthetic product or derivative and is not a true precursor prohormone

Intraoperative parathyroid hormone assay-cutting the Gordian knot

Directory of Open Access Journals (Sweden)

Chandralekha Tampi

2014-01-01

Full Text Available Background: Hyperparathyroidism is treated by surgical excision of the hyperfunctioning parathyroid gland. In case of adenoma the single abnormal gland is removed, while in hyperplasias, a subtotal excision, that is, three-and-a-half of the four glands are removed. This therapeutic decision is made intraoperatively through frozen section evaluation and is sometimes problematic, due to a histological overlap between hyperplasia and the adenoma. The intraoperative parathyroid hormone (IOPTH assay, propogated in recent years, offers an elegant solution, with a high success rate, due to its ability to identify the removal of all hyperfunctioning parathyroid tissue. Aim: To study the feasibility of using IOPTH in our setting. Materials and Methods: Seven patients undergoing surgery for primary hyperparathyroidism had their IOPTH levels evaluated, along with the routine frozen and paraffin sections. Results: All seven patients showed more than a 50% intraoperative fall in serum PTH after excision of the abnormal gland. This was indicative of an adenoma and was confirmed by histopathological examination and normalization of serum calcium postoperatively. Conclusion: The intraoperative parathyroid hormone is a sensitive and specific guide to a complete removal of the abnormal parathyroid tissue. It can be incorporated without difficulty as an intraoperative guide and is superior to frozen section diagnosis in parathyroid surgery.

Two simple cleanup methods combined with LC-MS/MS for quantification of steroid hormones in in vivo and in vitro assays

DEFF Research Database (Denmark)

Weisser, Johan Juhl; Hansen, Cecilie Hurup; Poulsen, Rikke

2016-01-01

Measuring both progestagens, androgens, corticosteroids as well as estrogens with a single method makes it possible to investigate the effects of endocrine-disrupting chemicals (EDCs) on the main pathways in the mammalian steroidogenesis. This paper presents two simple methods for the determination...... of the major steroid hormones in biological matrixes using liquid chromatography tandem mass spectrometry (LC-MS(2)). A novel method was developed for the determination of 14 steroids in the H295R in vitro assay without the need for solid phase extraction (SPE) purification prior to LC-MS(2) analysis....... The in vitro assay was validated by exposing H295R cells to prochloraz for inhibiting steroid hormone secretion and by exposing cells to forskolin for inducing steroid hormone secretion. The developed method fulfills the recommendations for the H295R assay suggested by the OECD. Furthermore, a simple off...

Radiometric immunosorbent assay for the detection of anti-hormone-binding protein antibodies

International Nuclear Information System (INIS)

Pierce, E.A.; Dame, M.C.; DeLuca, H.F.

1986-01-01

A radiometric immunosorbent assay (RISA) for the detection of monoclonal antibodies to hormone-binding proteins has been developed. The assay involves incubating hybridoma supernatants in microtiter wells that have been coated with goat anti-mouse IgG antibodies. Any mouse IgG in the test supernatant is thus specifically retained in the wells. Radioactive ligand-binding protein complexes are then incubated in the wells. The presence of anti-binding protein antibodies in the supernatant is indicated by specific retention of radioactive ligand-binding protein complexes in the wells. Crude antigen preparations, such as tissue homogenates, can be used to detect antibodies. The assay is capable of detecting antibody at concentrations 20 ng/ml (approx. 100 pM IgG). The RISA has been used successfully to screen for monoclonal antibodies to the intracellular receptor for 1,25-dihydroxyvitamin D 3 and should be useful for the detection of antibodies to ligand-binding proteins in general

Analysis of therapeutic growth hormone preparations: report of an interlaboratory collaborative study on growth hormone assay methodologies.

Science.gov (United States)

Bristow, A F; Jeffcoate, S L

1992-09-01

Recombinant DNA-derived human growth hormone (somatotropin) is widely used to treat growth hormone-deficient children. The potency of this product is determined by in-vivo bioassay in hypophysectomized rats, which is imprecise, costly and invasive, and there have been suggestions that it could safely be replaced with in-vitro or physico-chemical alternatives. In this report we present the results of a collaborative study designed to test this proposal. Somatotropin was modified by mild or severe proteolysis, mild or severe oxidation or treatment at high pH, and compared in a multi-centre collaborative study with unmodified somatotropin or with dimerized somatotropin. Participating laboratories included manufacturers and national control laboratories, and pharmacopoeial bioassays were compared with in-house in-vitro and physico-chemical bioassays. Although performing adequately with untreated somatotropin, for degraded samples the in-vivo bioassays were relatively unresponsive to changes in the growth hormone molecule. In contrast, the physico-chemical assays, in particular the reverse-phase HPLC, performed with a high degree of selectivity. We conclude that in the case of somatotropin, the in-vivo bioassay can be removed from the routine product specification with an acceptable degree of security. This however does not obviate the requirement rigorously to demonstrate biological activity in-vivo during product development, nor may the conclusions of this study be applied to other therapeutic recombinant proteins without similar collaborative investigations.

Development of a radioreceptor assay for human chorion gonadotropin: Application in normal and pathological pregnancies

International Nuclear Information System (INIS)

Koch, R.

1978-01-01

Rats testes were homogenised, and the binding capacity of several dilutions of these were tested with iodine 125 -labelled human choriongonadotropin. Investigations about binding over a period of 36 hrs. with 3 different temperatures, inhibition tests and cross reaction analyses for determining the specificity were carried out. 2 assay systems could be developed. The highly sensitive assay was applied at early pregnancy, at suspected disturbed or ectopic gravidity and allowed to measure the hCG-serum concentration above the physiological basal secretion of hLH. The less sensitive assay was used for measuring hCG in later stages of pregnancy, chorionepitheliomas and other hCG producing tumours. With the highly sensitive and specific assay, hCG was determinable 8 to 10 days post conceptionem. (orig.) [de

Evaluation of some magnetizable immunosorbents in radioimmunoassays and immunoradiometric assays of hormones

International Nuclear Information System (INIS)

Jyotsna, N.; Kadwad, V.; Sivaprasad, N.; Nirmala, V.; Pal, N.; Singh, Y.; Karir, T.; Chouthkantiwar, V.; Paradkar, S.

1996-01-01

Immunoassays are now indispensable clinical tools in many laboratories. An essential requirement for achieving reliable assays is an efficient and clean method for separating the immune complexes from the unreacted reagents. The development of a wide variety of solid phase separation methods has contributed significantly towards the reliability and simplification of immunoassays. Antibody coated macro one-piece surfaces like plastic beads or tubes are very popular but require great skill and control at all stages of manufacture. On the other hand, finely divided supports especially magnetizable particles are cheaper and simpler to develop. A variety of materials have been used in immunoassays. Black iron oxide Fe 3 O 4 is the most commonly used material and it is generally coated with polymeric materials like polymerized alkyl silanes, m-diaminobenzene, polyacrylamide, polyacrolein, or cellulose to facilitate covalent coupling of the antibodies. In this project we have evaluated some magnetizable particles for use in RIAs and IRMAs of hormones. The particles include Fe 3 0 4 , silane coated iron oxide, polyacrolein coated iron oxide and magnetizable cellulose. Second antibody (anti rabbit IgG.) was coupled to the particles for use in RIA of T 3 , T 4 , HCG, LH and progesterone, while monoclonal antibodies were coupled for the IRMAs of TSH, FSH and prolactin (hPrl). The influence of conditions such as reaction time, ratio of antibody to particles, and stability of the adsorbents and assay performance have been studied. For developing IRMAs for TSH, FSH and prolactin, monoclonal antibodies for each of these hormones were tested using magnetizable cellulose as the solid phase. We have also prepared silanized Fe 3 0 4 particles using Hungarian magnetite particles, and also prepared magnetizable cellulose by a simple grinding process. Both these materials are being tried out in different assays. Preliminary results have been encouraging. (author). 7 refs, 3 figs, 9 tabs

Hormonal changes in secondary impotence

International Nuclear Information System (INIS)

Salama, F.M.; El-Shabrawy, N.O.; Nosseir, S.A.; Abo El-Azayem, Naglaa.

1985-01-01

Impotence is one of the problems which is still obscure both in its aetiology and treatment. The present study deals with the possible hormonal changes in cases of secondary infertility. The study involved 25 patients diagnosed as secondary impotence. Hormonal assay was performed for the following hormones: 1. Prolaction hormone. 2. Luteinising hormone (L.H.). 3. Testosterone. 4. Follicle stimulating hormone (F.S.H.). The assay was carried out by radioimmunoassay using double antibody technique. Results are discussed

Clinical experience with a radioreceptor assay for TSH-binding inhibiting immunoglobulins (TBII)

International Nuclear Information System (INIS)

Heberling, H.J.; Bierwolf, B.; Lohmann, D.

1988-01-01

The aim was evaluate the clinical value of a commercial kit for determination of TSH-binding inhibiting immunoglobulin (TBII). 47 of 50 patients with untreated hyperthyroid Graves' disease were TBII positive (sensitivity 94%). TBII was in the normal range in all normal volunteers and in patients with simple goiter, thyroid cancer and in most cases of nonimmunogenic hyperthyreoidism (19 of 22). After 12 months antithyroid drug therapy with methimazole of 21 patients the prevalence of positive TBII findings was 28%. In contrast to this, 50 percent of the patients had increased microsomal antibodies at the end of therapy. The determination of TBII by TRAK assay proved to be a sensitive, specific and practical method. The assay can be used to differentiate between hyperthyreoidism of autoimmune or nonimmunogenic origin. Even so this method seems to be helpful for the follow-up during medical treatment of patients with Graves' disease. The results indicate that persistence of increased TBII levels are markers of active Graves' disease and suggest that in this situation ablative measures should be performed. Normalization of TBII on the end of a longstanding antithyroid therapy does not exclude the possibility of relapse in the further course. (author)

Establishment and clinical application of immunoradiometric assay for human growth hormone in serum

International Nuclear Information System (INIS)

Ji Jinfeng; Wu Congyuan; Niu Zhanpo; Zhang Kui; Song Ailing; Deng Jieying; Shi Mifan

1992-01-01

An immunoradiometric assay (IRMA) for human growth hormone (hGH) in serum is developed based on two high specific monoclonal antibodies against hGh. It can specifically detect the levels of serum bioactive hGh and had no cross-reaction with human prolactin (hPRL) and hGh oligmeric forms. The sensitivity was 0.2 ng/ml and the recovery for different concentrations of hGh was 92.0% ∼ 103.2%. The coefficients of variation for intra and inter-assay were<9.1% and <14.2%, respectively. Integral analysis of the results of RIA and IRMA with the patients' clinical manifestations revealed that hGh IRMA is better than hGh RIA in reflecting the clinical states of different acromegalic patients

Radioreceptor assay study of thyrotropin receptor antibody (TRAb) in Grave's diseases

International Nuclear Information System (INIS)

Lu Chao; Lin Xiangtong

1989-01-01

Here was reported the assay system using pig thyroid TSH receptor and 125 I-bTSH purified by receptor of thyroid cell membrane for the study of TRAb activity. The binding rate of ASH soluble receptor with 125 I-bTSH was 22.2 ∼ 37.4%, while as the control was only 1.0 ∼ 2.1%. TRAb was measured clinically in 48 cases of Grave's diseases and 25 normal persons. The TSH binding inhabitory index(TRII) was introduced for reflection of TRAb activity. The results showed that TBII was positure in 30 of 48 patients of Grave's diseases, the detctactibility was 79.2%

Multicenter analytical performance evaluation of a fully automated anti-Müllerian hormone assay and reference interval determination

NARCIS (Netherlands)

Anckaert, E.; Öktem, M.; Thies, A.; Cohen-Bacrie, M.; Daan, N. M P; Schiettecatte, J.; Müller, C.; Topcu, D.; Gröning, A.; Ternaux, F.; Engel, C.; Engelmann, S.; Milczynski, C.

2016-01-01

Objectives: Anti-Müllerian hormone (AMH) is an established biomarker for assessing ovarian reserve and predicting response to controlled ovarian stimulation. Its routine clinical use is hampered by the variability and low-throughput of available enzyme-linked immunosorbent assays (ELISA). The

The use of intermediate electron acceptors to enhance MTT bioreduction in a microculture tetrazolium assay for human growth hormone.

Science.gov (United States)

Goodwin, C J; Holt, S J; Downes, S; Marshall, N J

1996-01-01

We contrast the effects of three intermediate electron acceptors (IEAs) on the highly quantitative ESTA bioassay for human growth hormone. This is a microculture tetrazolium assay based upon the in vitro reduction of the tetrazolium salt MTT, by Nb2 cells which have been activated with hGH. Each of the IEAs influenced MTT-formazan production in a distinctive manner. The two quinonoids, namely menadione and co-enzyme Q0 markedly increased the MTT-formazan produced by hormone activated Nb2 cells and thereby amplified the response of our bioassay for human growth hormone (hGH). The exceptionally low bioassay baseline which is characteristic of the unstimulated Nb2 cells when only MTT is added was retained in the presence of CoQ0, but was greatly increased by menadione. Phenazine methosulphate, which is the most widely used redox intermediary in microculture tetrazolium assays, also increased the baseline, but had only a minimal additional effect on MTT reduction by activated Nb2 cells. We conclude that CoQ0 is the preferred IEA for this ESTA bioassay for hGH.

Pancreatic polypeptide: Identification of target tissues and investigation of possible physiologic significance

International Nuclear Information System (INIS)

Shetzline, M.A.

1988-01-01

Pancreatic Polypeptide (PP) is a 36 amino acid peptide with hormonal properties but whose physiologic function remains unknown. In order to determine the function of this peptide we investigated potential target tissues using an in vivo radioreceptor assay. In vitro high concentrations of unlabeled hormone competitively inhibit low concentrations of labeled hormone from binding to receptors. Our in vivo studies indicate that, in the presence of concentrated unlabeled peptide, labeled PP distributes between the plasma and interstitial fluid. When saline rather than excess unlabeled PP is injected, the labeled peptide appears to distribute in a volume exceeding the combined plasma and interstitial fluid volume of tissue. The distribution volume which exceeds the anatomic extracellular volume and which is not present with excess unlabeled peptide, is the receptor compartment. With this assay we demonstrated in the rat specific and displaceable PP binding to the ductus choledochus, duodenum, ileum, and adrenal gland. In vitro rat adrenal cell membranes showed specific I-125 labeled PP binding. Specific binding also occurred in bovine cortical and medullary membranes

Some important concepts in development of radioimmunoassay (RIA) for hormones, viruses and drugs. [Peptide hormones, non-peptide hormones

Energy Technology Data Exchange (ETDEWEB)

Shah, K B; Mani, R S [Bhabha Atomic Research Centre, Bombay (India). Radiopharmaceuticals Section

1981-01-01

Radioimmunoassay (RIA) procedures for the quantitative measurement of polypeptide and steroid hormones and other substances of medical and biological interest constitute one of the most important and rapidly expanding groups of applications of radioactive tracers in analytical chemistry and the life sciences. The method consists in setting up assays wherein the isotopically tagged substance is allowed to compete with its non-radioactive counterpart for the limited binding sites of a specific antibody. The degree of competitive inhibition of binding of labelled tracer is determined by measuring the radioactivity of the bound or unbound (free) complex, and comparing with the corresponding values for standard solutions of known concentration. This paper outlines the salient features, and specific problems associated with the preparation, purification of immunoreactive labelled tracers, and other suitable RIA reagents, the stability and storage conditions and standardisation of assay procedure. The characteristics of the assay systems have been investigated in detail and regular quality control has been instituted for evaluating various statistical parameters, inter-assay and intra-assay variances, and effective shelf life of the RIA reagents, with specific reference to assays of insulin growth hormones and thyroid and pregnancy hormones.

Two new automated, compared with two enzyme-linked immunosorbent, antimüllerian hormone assays.

Science.gov (United States)

Nelson, Scott M; Pastuszek, Ewa; Kloss, Grzegorz; Malinowska, Iwona; Liss, Joanna; Lukaszuk, Aron; Plociennik, Lukasz; Lukaszuk, Krzysztof

2015-10-01

To compare new automated antimüllerian hormone (AMH) assay performance characteristics from the new automated Elecsys AMH (Roche; Elecsys) and Access AMH (Beckman Coulter; Access) assays with the existing AMH Gen II ELISA (enzyme-linked immunosorbent assay; Gen II; Beckman Coulter) and AMH ELISA (Ansh Labs) assays. Prospective assay evaluation. University-affiliated clinical chemistry laboratory. Patients referred for serum AMH measurement (n = 83) before start of in vitro fertilization cycle between September 2014 and October 2014. None. Serum AMH concentration. Intra-assay coefficients of variation were low; Ansh ≤ 9.0%; Gen II ≤ 5.8%; Access ≤ 10.7%; and Elecsys ≤ 2.8%. The Passing-Bablok regression equations (pmol/L) were y (Access) = 0.128 + (0.781 × Gen II); and y (Access) = 0.302 + (0.742 x Ansh). For y (Elecys) = 0.087 + (0.729 x Gen II) and y (Elecys) = 0.253 + (0.688 x Ansh Labs). For y (Elecys) = 0.943 - (0.037 × Access). For all the assays, AMH exhibited a moderate positive correlation with AFC (r = 0.62-0.64); number of cumulus oocyte complexes (r = 0.60-0.64); and metaphase II oocytes (r = 0.48-0.50). Accuracy of pregnancy prediction, as determined by area under the receiver operating characteristic curve, was uniformly low for all assays (0.62-0.63). The novel automated assays exhibit strong concordance in calibration, but derived values are substantially lower than those obtained from pre-existing assays, with assay-specific interpretation required for routine clinical use. These results highlight the need for an international standard of measurement of AMH. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Usefulness of a rapid immunometric assay for intraoperative parathyroid hormone measurements

Directory of Open Access Journals (Sweden)

M.N. Ohe

2003-06-01

Full Text Available Intraoperative parathyroid hormone (IO-PTH measurements have been proposed to improve operative success rates in primary, secondary and tertiary hyperparathyroidism (PHP, SHP and THP. Thirty-one patients requiring parathyroidectomy were evaluated retrospectively from June 2000 to January 2002. Sixteen had PHP, 7 SHP and 8 THP. Serum samples were taken at times 0 (before resection, 10, 20 and 30 min after resection of each abnormal parathyroid gland. Samples from 28 patients were frozen at -70ºC for subsequent tests, whereas samples from three patients were tested while surgery was being performed. IO-PTH was measured using the Elecsys immunochemiluminometric assay (Roche, Mannheim, Germany. The time necessary to perform the assay was 9 min. All samples had a second measurement taken by a conventional immunofluorimetric method. We considered as cured patients who presented normocalcemia in PHP and THP, and normal levels of PTH in SHP one month after surgery and who remained in this condition throughout the follow-up of 1 to 20 months. When rapid PTH assay was compared with a routine immunofluorimetric assay, excellent correlation was observed (r = 0.959, P < 0.0001. IO-PTH measurement showed a rapid average decline of 78.8% in PTH 10 min after adenoma resection in PHP and all patients were cured. SHP patients had an average IO-PTH decrease of 89% 30 min after total parathyroidectomy and cure was observed in 85.7%. THP showed an average IO-PTH decrease of 91.9%, and cure was obtained in 87.5% of patients. IO-PTH can be a useful tool that might improve the rate of successful treatment of PHP, SHP and THP.

Development of radiometric assays for quantification of enzyme activities of the key enzymes of thyroid hormones metabolism

Czech Academy of Sciences Publication Activity Database

Pavelka, Stanislav

2014-01-01

Roč. 63, Suppl.1 (2014), S133-S140 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) 7AMB12SK158; GA ČR(CZ) GA304/08/0256 Institutional support: RVO:67985823 Keywords : enzyme * metabolism * radiometric assay * thyroid hormone Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.293, year: 2014

Radioimmunoassay of thyroid hormones

International Nuclear Information System (INIS)

Bartalena, L.; Mariotti, S.; Pinchera, A.

1987-01-01

For many years, methods based on iodine content determination have represented the only techniques available for the estimation of total thyroid hormone concentrations in serum. Subsequently, simple, sensitive, and specific radioligand assays for thyroid hormones have replaced these chemical methods. For the purpose of this chapter, iodometric techniques are only briefly summarized for their historical importance, whereas attention is focused on radioligand assays

Radioimmunoassay and related procedures in medicine

International Nuclear Information System (INIS)

1978-01-01

Full text: Radioassay procedures for the measurement of substances such as hormones, vitamins and drugs in the body fluids and tissues, above all in the blood, are now in the front rank of medical applications of radioactive materials. These procedures, which are carried out on specimens in the medical laboratory and do not involve the administration of any radioactive material to the patient, are now widely employed in the routine diagnosis and investigation of disease, whilst their use in research has led to important advances in many branches of medicine. Typical of radioassay methods is radioimmunoassay, which depends on the antigen-antibody reaction between the substance to be measured and the antibodies in an antiserum against that substance produced in a guinea-pig, rabbit, sheep or other animal. The importance of radioimmunoassay was recently underlined by the award of the Nobel Prize in medicine for 1977 to Dr. Rosalyn Yalow of the United States of America for her pioneer work on the method over the past two decades, particularly in relation to the measurement of protein hormones. This symposium was the third on the subject to have been sponsored by the IAEA. The first took place in Vienna in 1969 and the second in Istanbul in 1973. During the four years from 1973 to 1977, the growing commercial availability of reagents and kits for radioassays brought them into routine use. This in turn led to an increasing awareness of the need for assay standardization and quality control and to an increasing attention to techniques of assay data analysis. The burgeoning demands made on assay services stimulated interest in the possibilities for automation of assay procedures. Promising new methods were developed, notably solid-phase radioassay and radioreceptor assay. At the same time there was a resurgence of interest in alternative assay methods not based on the use of radioactive materials, which made a critical re-examination of the entire subject desirable. The

Radioimmunoassay and related procedures in medicine

Energy Technology Data Exchange (ETDEWEB)

NONE

1978-02-15

Full text: Radioassay procedures for the measurement of substances such as hormones, vitamins and drugs in the body fluids and tissues, above all in the blood, are now in the front rank of medical applications of radioactive materials. These procedures, which are carried out on specimens in the medical laboratory and do not involve the administration of any radioactive material to the patient, are now widely employed in the routine diagnosis and investigation of disease, whilst their use in research has led to important advances in many branches of medicine. Typical of radioassay methods is radioimmunoassay, which depends on the antigen-antibody reaction between the substance to be measured and the antibodies in an antiserum against that substance produced in a guinea-pig, rabbit, sheep or other animal. The importance of radioimmunoassay was recently underlined by the award of the Nobel Prize in medicine for 1977 to Dr. Rosalyn Yalow of the United States of America for her pioneer work on the method over the past two decades, particularly in relation to the measurement of protein hormones. This symposium was the third on the subject to have been sponsored by the IAEA. The first took place in Vienna in 1969 and the second in Istanbul in 1973. During the four years from 1973 to 1977, the growing commercial availability of reagents and kits for radioassays brought them into routine use. This in turn led to an increasing awareness of the need for assay standardization and quality control and to an increasing attention to techniques of assay data analysis. The burgeoning demands made on assay services stimulated interest in the possibilities for automation of assay procedures. Promising new methods were developed, notably solid-phase radioassay and radioreceptor assay. At the same time there was a resurgence of interest in alternative assay methods not based on the use of radioactive materials, which made a critical re-examination of the entire subject desirable. The

Competitive binding thyroid assay with improved bound-free separation step

International Nuclear Information System (INIS)

1979-01-01

A competitive binding assay is described for serum thyroid hormone using 125 I-labelled thyroid hormone and exogenous thyroid hormone binding protein. The unbound thyroid hormone is separated from thyroid hormone bound to thyroid hormone binding protein using an intermediate base anion exchange resin. This resin comprises tertiary and quaternary amine groups on a polyalkyleneamine lattice and is compressed with microcrystalline cellulose in a tablet form. The assay technique of the present invention employing an intermediate base anion resin was found to give superior results compared with alternative assay techniques used in serum thyroid hormone estimation. (UK)

Functional diagnostics for thyrotropin hormone receptor autoantibodies: bioassays prevail over binding assays.

Science.gov (United States)

Lytton, Simon David; Schluter, Anke; Banga, Paul J

2018-06-01

Autoantibodies to the thyrotropin hormone receptor (TSH-R) are directly responsible for the hyperthyroidism in Graves' disease and mediate orbital manifestations in Graves' orbitopathy (otherwise known as thyroid eye disease). These autoantibodies are heterogeneous in their function and collectively referred to as TRAbs. Measurement of TRAbs is clinically important for diagnosis of a variety of conditions and different commercial assays with high sensitivity and specificity are available for diagnostic purposes. This review provides overwhelming evidence that the TRAbs detected in binding assays by mainly the automated electrochemical luminescence immunoassays (ECLIA) do not distinguish TRAbs that stimulate the TSH-R (called TSIs or TSAbs) and TRAbs that just inhibit the binding of TSH without stimulating the TSH-R (called TBAbs). However, TSAbs and TBAbs have divergent pathogenic roles, and depending which fraction predominates cause different clinical symptoms and engender different therapeutic regimen. Therefore, diagnostic distinction of TSAbs and TBAbs is of paramount clinical importance. To date, only bioassays such as the Mc4 TSH-R bioassay (Thyretain TM , Quidel) and the Bridge assay (Immulite 2000, Siemens) can measure TSAbs, with only the former being able to distinguish between TSAbs and TBAbs. On this note, it is strongly recommended to only use the term TSI or TSAb when reporting the results of bioassays, whereas the results of automated TRAb binding assays should be reported as TRAbs (of undetermined functional significance). This review aims to present a technical and analytical account of leading commercial diagnostic methods of anti-TSH-R antibodies, a metaanalysis of their clinical performance and a perspective for the use of cell based TSH-R bioassays in the clinical diagnostics of Graves' disease.

Flow cytometric measurement of DNA level and steroid hormone receptor assay in breast cancer

International Nuclear Information System (INIS)

Zubrikhina, G.N.; Kuz'mina, Eh.V.; Bassalyk, L.S.; Murav'eva, N.I.

1989-01-01

DNA level measured by flow cytometry and estrogen and progesteron receptors assayed in tissue samples obtained from 85 malignant and 16 benign lesions of the breast. All the benign tumors revealed 2c DNA content and most of them were receptor-negative, while 74.1% of breast carcinomas displayed aneuploidy. Three patients (3.5%) had two lines of aneuploid cells. Many aneuploid tumors were receptor-negative. Preoperative radiation treatmet (14-20 Gy) did not significantly influence the level of steroid hormone receptors in tumors. Estrogen receptor level was higher in menopausal patients than in premenopausal ones

Interpretation of growth hormone provocative tests

DEFF Research Database (Denmark)

Andersson, A M; Orskov, H; Ranke, M B

1995-01-01

To compare interpretations of growth hormone (GH) provocative tests in laboratories using six different GH immunoassays (one enzymeimmunometric assay (EIMA, assay 1), one immunoradiometric assay (IRMA, assay 5), one time-resolved fluorimmunometric assay (TRFIA, assay 3) and three radioimmunoassays...

Clinical evaluation of the 2nd generation radio-receptor assay for anti-thyrotropin receptor antibodies (TRAb) in Graves' disease

International Nuclear Information System (INIS)

Giovanella, L.; Ceriani, L.; Garancini, S.

2002-01-01

Full text: Detection of autoantibodies to the TSH receptor by radioreceptorial assays (RRA) is largely requested in clinical practice for the diagnosis of Graves' disease and its differentiation from diffuse thyroid autonomy. Additionally, TRAb measurement during antithyroid drug treatment can be useful to evaluate the risk of disease's relapse alter therapy discontinuation. Nevertheless, some patients affected by Graves' disease are TRAb negative when 1st generation assay is used. Recently a new RRA method for TRAb assay was developed by using human recombinant TSH-receptor and solid-phase technique. Aim of our work was the comparison between 1st and 2nd generation TRAb assays in Graves' disease patients and, particularly, the evaluation of 2nd generation test in a sub-group of patients affected by Graves' disease but with negative 1st generation TRAb assay. We evaluated the diagnostic performance of a newly developed 2nd generation TRAb assay (DYNOtest(r) TRAK human, BRAHMS Diagnostica GmbH, Germany) in 46 patients affected by Graves' disease with negative 1st generation TRAb assay (TRAK Assay(r), BRAHMS Diagnostica GmbH, Germany) . A control groups of 50 Graves' disease patients with positive 1st generation TRAb assay, 50 patients affected by Hashimoto's thyroiditis and 50 patients affected by nodular goiter were also examined. 41 out of 46 patients affected by Graves' disease with negative 1st generation TRAb assay showed a positive 2nd generation test. The overall sensitivity of the 2nd generation test was significantly improved respect the 1st generation assay in Graves' disease patients (χ 2 = 22.5, p<0.0001). 1 and 3 out of 50 patients affected by Hashimoto's thyroiditis were positive by 1st and 2nd generation TRAB assay, respectively. All these patients showed primary hypothyroidism. No differences resulted in euthyroid Hashimoto's thyroiditis sub-group and in nodular goiter control group. The 2nd generation TRAB assay is clearly more sensitive than the 1

Clinical value of determination of TSH-binding inhibiting immunoglobulins (TBII) by a radioreceptor assay

International Nuclear Information System (INIS)

Heberling, H.J.; Bierwolf, B.; Lohmann, D.

1986-01-01

The clinical value of a commercial kit for determination of TBII was evaluated. 50 patients with untreated Graves' disease, 21 patients with Graves' disease before and during medical therapy, 18 patients after finishing medical therapy and 10 patients after surgical treatment were examined. Besides these, 41 patients with other thyroid diseases and 36 patients without any thyroid disorder were included. In 47 (94%) of 50 patients with untreated Graves' disease TBII were detectable in serum using a TSH standard curve. Binding activities exceeding 10 U/l TSH equivalents were regarded as positive. In other thyroid diseases TBII were negative with the exception of 3 of 22 patient with autonomously functioning thyroid nodules. After 12 months of antithyroid drug treatment of 19 patients the incidence of positive antibody findings was 26%. During follow-up after medical therapy (1-9 years) 7 of 18 patients had increased TBII in correlation with clinical and functional findings. The determination of TBII by TRAK assay proved to be a sensitive and specific method. The assay can be used to differentiate between hyperthyroidism of autoimmune or non-immunogenic origin. Thus the method seems to be helpful for the follow-up under medical treatment of patients with Graves' disease. (author)

Insulin-like growth factors: assay methods and their implications

International Nuclear Information System (INIS)

Guyda, H.J.; Posner, B.I.; Schiffrin, A.; Rappaport, R.; Postel-Vinay, M.C.; Corvol, M.T.

1981-01-01

The insulin-like growth factors (IGF's) are small molecular weight peptides (6-10 x 10 3 daltons) that circulate in blood plasma almost entirely bound to macromolecular carrier proteins. The growth-promoting and insulin-like activities of IGF's can be explained by the observed ability of these peptides to interact with the IGF receptor on the one hand and with the insulin receptor on the other. These observations have led to the establishment of radioreceptor assays (RRA's), competitive protein binding assays (CPBA's), and more recently radioimmunoassays (RIA's) for the IGF's that have different specificities. Because of their ease of performance and sensitivity, the radioligand assays have largely supplanted the biological assays originally utilized to identify and characterize these anabolic peptides. In this report the authors' studies are summarised which utilize a slightly acidic IGF which has been purified on the basis of its insulin-like activity in an insulin RRA and which was termed ILAs. They refer to purified insulin-like peptides that have the properties of a somatomedin by the generic term insulin-like growth factor (IGF). Somatomedin (SM) activity will be utilized to connote that activity in plasma or serum determined by bioassay. The competitive dose-response curves for IGF peptides in the insulin RRA as well as those in the ILAs RRA are presented. A combination of bioassays, RRA and RIA were employed to assess somatomedin activity and IGF peptide levels in a number of clinical circumstances. The correlations are discussed. (Auth.)

Radioligand assay in reproductive biology

International Nuclear Information System (INIS)

Korenman, S.G.; Sherman, B.M.

1975-01-01

Radioligand assays have been developed for the principal reproductive steroids and peptide hormones. Specific binding reagents have included antibodies, plasma binders, and intracellular receptors. In each assay, problems of specificity, sensitivity, and nonspecific inhibitors were encountered. Many features of the endocrine physiology in childhood, during puberty, and in adulthood have been characterized. Hormonal evaluations of endocrine disorders of reproduction are characterized on the basis of their characteristic pathophysiologic alterations. (U.S.)

Rapid intraoperative parathyroid hormone assay--more than just a comfort measure.

LENUS (Irish Health Repository)

Hanif, F

2012-02-03

BACKGROUND: Minimally invasive radio-guided parathyroidectomy (MIRP) has been embraced as an acceptable therapeutic approach to primary hyperparathyroidism. Preoperative sestamibi scanning has facilitated this technique. Here we evaluate the addition of a rapid intraoperative parathyroid hormone (iPTH) assay for patients undergoing MIRP. METHODS: A series of 51 patients underwent sestamibi localization of parathyroid glands followed by MIRP for primary hyperparathyroidism. Using peripheral venous samples, iPTH levels were measured prior to gland excision, as well as post-excision at 5, 10, and 15 minutes, taking a 50% reduction in iPTH level as indicative of complete excision. Next, changes in serum iPTH were compared with preoperative and postoperative changes in serum calcium, as well as levels of intraoperative ex-vivo radiation counts taken by hand-held gamma probe. RESULTS: In this series, a drop of greater than 50% in iPTH levels was observed in 94% of patients (n=48). Moreover, a significant drop in iPTH occurred within 10 minutes of excision in the majority (n=42) of cases (P<0.004). Changes in iPTH were comparable with the therapeutic reduction in calcium levels, as well as with the change in intraoperative ex-vivo gamma counts. CONCLUSIONS: This study demonstrates that the addition of an iPTH assay to MIRP provides a quick and reliable intraoperative diagnostic modality in confirming correct adenoma removal. Moreover, it precludes the requirement of frozen section.

Hormone Receptor Expression Analyses in Neoplastic and Non-Neoplastic Canine Mammary Tissue by a Bead Based Multiplex Branched DNA Assay: A Gene Expression Study in Fresh Frozen and Formalin-Fixed, Paraffin-Embedded Samples.

Directory of Open Access Journals (Sweden)

Annika Mohr

Full Text Available Immunohistochemistry (IHC is currently considered the method of choice for steroid hormone receptor status evaluation in human breast cancer and, therefore, it is commonly utilized for assessing canine mammary tumors. In case of low hormone receptor expression, IHC is limited and thus is complemented by molecular analyses. In the present study, a multiplex bDNA assay was evaluated as a method for hormone receptor gene expression detection in canine mammary tissues. Estrogen receptor (ESR1, progesterone receptor (PGR, prolactin receptor (PRLR and growth hormone receptor (GHR gene expressions were evaluated in neoplastic and non-neoplastic canine mammary tissues. A set of 119 fresh frozen and 180 formalin-fixed, paraffin-embedded (FFPE was comparatively analyzed and used for assay evaluation. Furthermore, a possible association between the hormone receptor expression in different histological subtypes of canine malignant mammary tumors and the castration status, breed and invasive growth of the tumor were analyzed. The multiplex bDNA assay proved to be more sensitive for fresh frozen specimens. Hormone receptor expression found was significantly decreased in malignant mammary tumors in comparison to non-neoplastic tissue and benign mammary tumors. Among the histological subtypes the lowest gene expression levels of ESR1, PGR and PRLR were found in solid, anaplastic and ductal carcinomas. In summary, the evaluation showed that the measurement of hormone receptors with the multiplex bDNA assay represents a practicable method for obtaining detailed quantitative information about gene expression in canine mammary tissue for future studies. Still, comparison with IHC or quantitative real-time PCR is needed for further validation of the present method.

Investigation of the immunological and receptor activity of human growth hormone in patients with acromegaly

International Nuclear Information System (INIS)

Dietz, A.

1982-01-01

Human growth hormone (hGH) was measured by means of the radioimmunoassay (RIA) and the radioreceptor assay (RRA). The receptors were liver plasma membranes (LPM) of pregnant rabbits. In the RIA, no cross-reaction was found with hPRL, whereas in the RRA the cross-reaction was 3 p.c. The Scatchard analysis revealed two binding sites for hGH at the receptor. Pre-treatment with hGH and Cortisol brought about an enhanced affinity without change of the specific bonding, whereas pre-treatment with bromocriptin showed no significant effect. Hypophyseal hGH was separated by means of gel chromatography into big-big and big-little hGH and a reduced receptor activity of the higher molecular hGH fraction was shown. The Scatchard analysis indicated a more unspecific bonding characteristic of the big hGH. Stimulation of hGH secretion by insulin hypoglycemia provoked an overproportional increase in big hGH in healthy persons, whereas in patients with acromegaly the secretion of little hGH was enhanced. The suppression of hGH secretion by long-term bromocriptin treatment led to a significant rise of the RIA/RRA quotient in patients with post-operative florid acromegaly. Acute administration of BC was shown to induce a stronger hGH drop in the RRA of responders than in their RIA, as compared to non-responders. By chromatographic separation it was found that in responders the secretion of little hGH is selectively inhibited, but no in non-responders. (orig.) [de

Bioprocessing feasibility analysis. [thymic hormone bioassay and electrophoresis

Science.gov (United States)

1978-01-01

The biology and pathophysiology of the thymus gland is discussed and a clinical procedure for thymic hormone assay is described. The separation of null lymphocytes from mice spleens and the functional characteristics of the cells after storage and transportation were investigated to develop a clinical procedure for thymic hormone assay, and to determine whether a ground-based approach will provide the desired end-product in sufficient quantities, or whether the microgravity of space should be exploited for more economical preparation of the hormone.

Determination of luteinizing hormone in bovine blood by radioligand receptor assay and comparison with radioimmunological evaluation

International Nuclear Information System (INIS)

Schams, D.; Menzer, C.

1978-01-01

A sensitive and specific radioligand receptor assay (RRA) using rat testis homogenate as the receptor source is described for measurement of luteinizing hormone (LH) in bovine blood. Interfering and nonspecific substances in blood were removed by means of ion-exchange chromatography on CM-Sephadex C-50. Criteria of validation such as recovery of added LH to plasma or serum, reproducibility, and specificity gave good results. Inhibition curves obtained with bovine plasma and serum were parallel to those obtained with the bovine standard preparation. The range of the dose-response curve was between 0.5-20 ng of bovine LH. The pattern of LH concentrations in purified serum samples under different physiological conditions such as during the oestrous cycle and after administration of GnRH showed a very close correlattion whether measured by means of radioimmunoassay (RIA) or receptor assay. Values of RRA-LH were consistently higher than those of RIA-LH. Thus the lower the RIA-LH levels, the more pronounced were the discrepancies between results of both assay systems. The mean ratio of RRA-LH/RIA-LH for basal levels (less than 1 ng RIA-LH/ml plasma) was 17.8 as compared to a mean ratio for higher peak values (more than 20 ng RIA-LH/ml plasma) of only 1.2. (author)

Correlations Between Seminal Plasma Hormones and Sperm ...

African Journals Online (AJOL)

Context: There is a complex relationship between seminal plasma hormone levels and infertility in men. Previous studies had shown no specific pattern in the serum or seminal plasma hormone profiles of men with infertility and it is debatable whether there is a need to perform routine seminal hormone assays in the ...

Radioimmunological and serological assay of the urinary excretion of the luteinizing hormone in women with amenorrhea

International Nuclear Information System (INIS)

Szymanski, W.

1975-01-01

The radioimmunological and serological assay of the urinary excretion of the luteinizing hormone (LH) was performed in 6 women treated with monopausal gonadotropin - because of amenorrhoe. The observations of the course of treatment demonstrated different concentration of LH in women treated because of primary and secondary amenorrhoe. In cases of primary amenorrhoe increase of the LH concentration appeared in the form of ovulation peak being closely correlated with the first injection of Biogonadyl (HCG) preparation. Different observations were made in the secondary amenorrhoe group, where urinary LH increase proceeded for some hours the adminstration of the exogenous chrionic gonadotropin. This may prove the induction of ovulation without the participation of HCG, as an effect of the menopausal gonadotropin (Menogonadyl) with established 1:1 ratio of FSH:LH. In the examined group of women with secondary amenorrhoe the radioimmunologic assay demonstrated persisting through several days high levels of urinary LH - undetectable by serological methods. In 4 cases corpus luteum appeared in the course of treatment - confirmed by cytologic examination and by determination of urainary pregnandiol activity. (author)

Abstracts of the 28. Annual meeting of the Brazilian Society on Biochemistry and Molecular Biology

International Nuclear Information System (INIS)

1999-01-01

Biochemistry, genetic and molecular biology aspects of either animals (including man), plants and microorganisms are studied. Topics such as cell membrane structures (including receptors), enzymatic assays, biological pathways, structural chemical analysis, metabolism, biological functions are focused. The use of radiolabelled compounds (radioassay, radioenzymatic assay, radioreceptor assay) and nuclear magnetic resonance are the most applied techniques

Immunoassay of serum polypeptide hormones by using 125I-labelled anti(-immunoglobulin G) antibodies.

Science.gov (United States)

Beck, P; Nicholas, H

1975-03-01

1. A technique for indirectly labelling antibodies to polypeptide hormones, by combining them with radioactively labelled anti-(immunoglobulin G) is described. (a) 125I-labelled anti-(rabbit immunoglobulin G) and anti-(guinea-pig immunoglobulin G) antibodies with high specific radioactivity were prepared after purification of the antibodies on immunoadsorbents containing the respective antigens. (b) Rabbit immunoglobulin G antibodies to human growth hormone, porcine glucagon and guinea-pig immunoglobulin G antibodies to bovine insulin and bovine parathyroid hormone were combined with immunoadsorbents containing the respective polypeptide hormone antigen. (c) The immunoglobulin G antibodies to the polypeptide hormones were reacted with 125-I-labelled anti-(immunoglobulin G) antibodies directed against the appropriate species of immunoglobulin G,and the anti-hormone antibodies were combined with the hormone-containing immunoadsorbent. (d) 125I-labelled anti-(immunoglobulin G) antibodies and anti-hormone antibodies were simultaneously eluted from the hormone-containing immunoadsorbent by dilute HCl, pH 2.0. After elution the anti-(immunoglobulin G) antibodies and antihormone antibodies were allowed to recombine at pH 8.0 and 4 degrees C. 2. The resultant immunoglobulin G-anti-immunoglobulin G complex was used in immunoradiometric (labelled antibody) and two-site assays of the respective polypeptide hormone. 3. By using these immunoassays, concentrations down to 90pg of human growth hormone/ml, 100 pg of bovine insulin/ml, 80 pg of bovine parathyroid hormone/ml and 150 pg of glucagon/ml were readily detected. Assays of human plasma for growth hormone and insulin by these methods showed good agreement with results obtained by using a directly 125I-labelled anti-hormone antibody in an immunoradiometric assay of human growth hormone or by radioimmunoassay of human insulin. 4. The method described allows immunoradiometric or two-site assays to be performed starting with as

Surface plasmon resonance immunoassay analysis of pituitary hormones in urine and serum samples.

Science.gov (United States)

Treviño, Juan; Calle, Ana; Rodríguez-Frade, José Miguel; Mellado, Mario; Lechuga, Laura M

2009-05-01

Direct determination of four pituitary peptide hormones: human thyroid stimulating hormone (hTSH), growth hormone (hGH), follicle stimulating hormone (hFSH), and luteinizing hormone (hLH) has been carried out using a portable surface plasmon resonance (SPR) immunosensor. A commercial SPR biosensor was employed. The immobilization of the hormones was optimized and monoclonal antibodies were selected in order to obtain the best sensor performance. Assay parameters as running buffer and regeneration solution composition or antibody concentration were adjusted to achieve a sensitive analyte detection. The performance of the assays was assessed in buffer solution, serum and urine, showing sensitivity in the range from 1 to 6 ng/mL. The covalent attachment of the hormones ensured the stability of the SPR signal through repeated use in up to 100 consecutive assay cycles. Mean intra- and inter-day coefficients of variation were all <7%, while batch-assay variability using different sensor surfaces was <5%. Taking account both the excellent reutilization performance and the outstanding reproducibility, this SPR immunoassay method turns on a highly reliable tool for endocrine monitoring in laboratory and point-of-care (POC) settings.

Abstracts of the 29. annual meeting of the Brazilian Society on Biochemistry and Molecular Biology

International Nuclear Information System (INIS)

2000-01-01

Several aspects concerning biochemistry and molecular biology of either animals (including man), plants and microorganisms are studied. Topics such as cell membrane structures (including receptors), enzymatic assays, biological pathways, structural chemical analysis, metabolism, biological functions are focused. The use of radiolabelled compounds (radioassay, radioenzymatic assay, radioreceptor assay and nuclear magnetic resonance are the most applied techniques

Application of europium(III) chelates-bonded silica nanoparticle in time-resolved immunofluorometric detection assay for human thyroid stimulating hormone

International Nuclear Information System (INIS)

Zhou Yulin; Xia Xiaohu; Xu Ye; Ke Wei; Yang Wei; Li Qingge

2012-01-01

Highlights: ► A rapid and ultrasensitive TSH immunoassay was developed using fluorescent silica nanoparticles-based TrIFA. ► The assay is of high sensitivity with short period time request. ► method can be potentially used at hospitals for daily clinical practice in hTSH screening. - Abstract: Eu(III) chelate-bonded silica nanoparticle was used as a fluorescent label to develop a highly sensitive time-resolved immunofluorometric assay (TrIFA) for human thyroid stimulating hormone (hTSH). The limit of detection of the assay calculated according to the 2SD method was 0.0007 mIU L −1 and became 0.003 mIU L −1 when serum-based matrix was used for calibrators, indicating that this TrIFA is comparable with the most sensitive assays. The linear range was from 0.005 to 100 mIU L −1 of hTSH with coefficient of variation between 1.9% and 8.3%. The correlation study using 204 blood spot samples from newborns showed that the results from this new method were coincident with that of the commercial dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA) system, with a correlation coefficient of 0.938. The fluorescent nanoparticle label allows directly reading the fluorescent signal, omitting the signal development step required for the DELFIA system, and the whole procedure of this assay is fulfilled within 2 h. Thus, we developed a novel, sensitive, quantitative and simple nanoparticle label-based TrIFA assay, suitable for routine application in hTSH screening of neonatal hypothyroidism.

Application of europium(III) chelates-bonded silica nanoparticle in time-resolved immunofluorometric detection assay for human thyroid stimulating hormone

Energy Technology Data Exchange (ETDEWEB)

Zhou Yulin [Xiamen Branch of Fujian Newborn Screening Centre and Xiamen Prenatal Diagnosis Centre, Xiamen Maternal and Children' s Health Care Hospital, Xiamen, Fujian 361003 (China); Xia Xiaohu; Xu Ye; Ke Wei [Engineering Research Centre of Molecular Diagnostics Laboratory, MOE, Department of Biomedical Sciences and the Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005 (China); Yang Wei, E-mail: weiyang@xmu.edu.cn [Engineering Research Centre of Molecular Diagnostics Laboratory, MOE, Department of Biomedical Sciences and the Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005 (China); Li Qingge, E-mail: qgli@xmu.edu.cn [Engineering Research Centre of Molecular Diagnostics Laboratory, MOE, Department of Biomedical Sciences and the Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005 (China)

2012-04-13

Highlights: Black-Right-Pointing-Pointer A rapid and ultrasensitive TSH immunoassay was developed using fluorescent silica nanoparticles-based TrIFA. Black-Right-Pointing-Pointer The assay is of high sensitivity with short period time request. Black-Right-Pointing-Pointer method can be potentially used at hospitals for daily clinical practice in hTSH screening. - Abstract: Eu(III) chelate-bonded silica nanoparticle was used as a fluorescent label to develop a highly sensitive time-resolved immunofluorometric assay (TrIFA) for human thyroid stimulating hormone (hTSH). The limit of detection of the assay calculated according to the 2SD method was 0.0007 mIU L{sup -1} and became 0.003 mIU L{sup -1} when serum-based matrix was used for calibrators, indicating that this TrIFA is comparable with the most sensitive assays. The linear range was from 0.005 to 100 mIU L{sup -1} of hTSH with coefficient of variation between 1.9% and 8.3%. The correlation study using 204 blood spot samples from newborns showed that the results from this new method were coincident with that of the commercial dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA) system, with a correlation coefficient of 0.938. The fluorescent nanoparticle label allows directly reading the fluorescent signal, omitting the signal development step required for the DELFIA system, and the whole procedure of this assay is fulfilled within 2 h. Thus, we developed a novel, sensitive, quantitative and simple nanoparticle label-based TrIFA assay, suitable for routine application in hTSH screening of neonatal hypothyroidism.

Haloperidol plasmatic levels and their clinical response to the treatment. Comparison between the radioimmunoassay and radioreceptorassay: preliminary data

Energy Technology Data Exchange (ETDEWEB)

Cabranes, J A; Almoguera, I; Santos, J L; Prieto, P; Ramos, J A

1988-06-01

Schizophrenic patients were treated with haloperidol. Their haloperidol levels in plasma were determined with radioimmunoassay (RIA) and radioreceptor assay (RRA). The results obtained are compared with the clinical improvement. (M.C.B.).

Haloperidol plasmatic levels and their clinical response to the treatment

International Nuclear Information System (INIS)

Cabranes, J.A.; Almoguera, I.; Santos, J.L.; Prieto, P.; Ramos, J.A.

1988-01-01

Schizophrenic patients were treated with haloperidol. Their haloperidol levels in plasma were determined with radioimmunoassay (RIA) and radioreceptor assay (RRA). The results obtained are compared with the clinical improvement. (M.C.B.)

Characterisation of monoclonal antibodies for human luteinising hormone, and mapping of antigenic determinants on the hormone

International Nuclear Information System (INIS)

Soos, M.; Siddle, K.

1983-01-01

Twelve mouse monoclonal antibodies for human luteinising hormone were produced. The affinities varied from 4 X 10 7 to 1 X 10 10 l/mol. The specificity of each antibody was assessed by determining the relative reactivities with luteinising hormone, thyroid stimulating hormone, follicle stimulating hormone and chorionic gonadotrophin. Six antibodies bound to the α-subunit as shown by similar reactivity with all hormones, and the remainder to the β-subunit as shown by specificity for luteinising hormone. This latter group of antibodies cross-reacted only weakly with thyroid stimulating hormone (approximately 10%) and follicle stimulating hormone (approximately 3%). Three of these antibodies also showed low reactivity towards chorionic gonadotrophin (<10%), though the others did not (80-300%). The ability of different antibodies to bind simultaneously to luteinising hormone was examined and it was shown that several distinct antigenic determinants existed on both subunits. The characterisation of monoclonal binding sites is discussed in relation to the use of antibodies in two-site immunoradiometric assays. (Auth.)

Methodologic and clinical aspects of free thyroid hormone assay

International Nuclear Information System (INIS)

Hermans, J.; Baldewyns, P.; Beauduin, M.

1984-01-01

The diagnostic value of free thyroid hormones measures depends on used technic. The results gived by two different kits are compared: - Kit Le Petit with chromatographic separation, - Kit Amersham which uses an analogue [fr

Abstracts of the 30. Annual meeting of the Brazilian Society on Biochemistry and Molecular Biology

International Nuclear Information System (INIS)

2001-01-01

Several aspects concerning biochemistry and molecular biology of either animals, plants and microorganisms are studied. Topics such as cell membrane structures (including receptors), enzymatic assays, biological pathways, structural chemical analysis, metabolism, biological functions are focused. The use of radiolabelled compounds (radioassay, radioreceptor assay) and nuclear magnetic resonance are the most applied techniques

Immunoassays for the incretin hormones GIP and GLP-1

DEFF Research Database (Denmark)

Deacon, Carolyn F; Holst, Jens J

2009-01-01

The measurement of the incretin hormones, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), using immunologically based assays is made difficult by the fact that the processing of the precursor molecules gives rise to a number of different peptides which cross......-react with antisera raised against the two hormones. For GLP-1, the picture is further complicated because of the necessity to differentiate between the intestinal and pancreatic proglucagon products. Finally, once secreted, both incretins are rapidly degraded by the enzyme dipeptidyl peptidase-4 (DPP-4) to generate....... The use of highly specific assays using well-characterised antisera and careful sample handling is therefore required for a reliable determination of incretin hormone concentrations....

The effect of ovarian steroid feedback upon radioimmunoreactive luteinizing hormone releasing hormone in the hypothalamus

International Nuclear Information System (INIS)

Yanaihara, Takumi; Arai, Kiyoshi; Kanazawa, Motomi; Okinaga, Shoichi; Yanaihara, Noboru

1975-01-01

A radioimmunoassay (RIA) method for luteinizing hormone (LH) releasing hormone (RH) utilizing rabbit antiserum against synthetic (Glu 1 )-LH-RH coupled with human serum albumin at the N-terminus, is described. This assay system for LH-RH also cross-reacted with several LH-RH analogues or fragments, but not with pituitary trophic hormones. The assay was performed on the hypothalamic extracts of adult ovariectomized rats and female immature rats which had been treated with estradiol. The FSH and LH levels in the pituitary gland and serum of the same animals were determined by RIA. The radioimmunoreactive LH-RH content of the stalk median eminence markedly increased seven days after ovariectomy. The serum levels and the pituitary contents of FSH and LH of the same rats were also significantly augmented. In immature rats, the hypothalamic content of LH-RH, as measured by RIA, was significantly increased one hour after the injection of estradiol. The FSH and LH levels in the pituitary showed a significant rise after 7 hours. (auth.)

Preparation of a homogeneous extract of human growth hormone, isohormone B, and its 125I-labelling for utilization in radioligand assays

International Nuclear Information System (INIS)

Santos, A.J. dos.

1985-01-01

Non-destructive polyacrylamide gel electrophoretic (PAGE) tecnique, with direct UV-densitometry, was set up to permit both qualitative and quantitative studies of human growth hormone (hGH) isohormone purification is presented. This tecnique was used on a preparative scale to obtain milligram amounts of the fundamental form of hGH, isohormone B(Ih-B). Reversed electrophoresis was employed to elute the protein band form the gel. Retention of bio-and immunoactivity was demonstrated via two separate experiments. An 'in vivo' bioassay, based on the weight increase of hypophysectomized rats with a 2 x 2 factorial assay design, was used to compare the true somatotrophic activity of an hGH preparation submitted to the purification process with that of a single control preparation. Retention of immunoactivity was confirmed by studying the antibody binding properties of purified and radioiodinated Ih-B and by determination of its absolute immunopotency against a calibrated secondary standard. Radioimmuno assay curves, determined using Ih-B, as a standard and labelled preparation, showed its applicability in setting up assays based on more homogeneous reagents. (Author) [pt

Radioimmunoassay of hormones for clinical trials of fertility regulating agents in developing countries

International Nuclear Information System (INIS)

1975-01-01

The need for accurate hormonal assay is emphasized, and becomes more urgent as hormones, in addition to their conventional medical use are being increasinly used for family planning purposes, particularly in developing countries. Readily available facilities and laboratories for the assay of hormone strength are therefore required, and also for the standardization of methods and techniques for such assays. Radioimmunology appears and excellent tool for this. Analytical techniques in actual use and techniques of potential future use are considered. Techniques for assessing hormone strength, potenty and doses are outlined. Criteria are developed, required for establishing a calibration and standardization laboratory for hormone strength. These criteria include a discussion of the necessary staff, location of such a facility and the material and equipment needed. Help from consultants, staff training, and the growth in sample analysis and corresponding financial aspects are discussed. Finally, the problems are reviewed of creating national laboratories which can be developed as services available for certain geographical regions

Free thyroid hormones in patients with severe non-thyroidal illness

International Nuclear Information System (INIS)

Boettger, I.; Schneck, H.W.; Technische Univ. Muenchen

1985-01-01

Free thyroid hormone radioligand assays and indirect methods for FT 4 and FT 3 were applied to measurement in sera of patients with severe NTI (hemodialysis, intensive-care, polytrauma). FT 4 by different techniques was low-normal to decreased by a kinetic two-tube and a T 4 -analogue tracer single-tube assay whereas another two-tube technique measured normal to low-normal but in some instances increased FT 4 levels. Indirect parameters behaved in a similar fashion. FT 3 was decreased in most of the cases as were the indirect parameters, mostly due to affected T 4 -T 3 conversion. Direct and indirect parameters for free thyroid hormones changed in parallel also during follow-up of NTI. There was no clear protein or albumen effect upon the two-tube FT 4 and the two-tube FT 3 assay(s). Supersensitively determined basal TSH was found to be decreased in some cases with severe NTI (polytrauma). The findings taken together are consistent with (pseudo) sedondary hypothyroidism in severe NTI. The data show the free thyroid hormone assays tested to be rather reliable with little or no disturbance by severe NTI or specifically hypoalbumenemia. (orig.)

Studies on the radioimmunoassay of thyroid hormones

International Nuclear Information System (INIS)

Kim, J.R.; Awh, O.D.; Park, K.B.; Kim, Y.S.

1980-01-01

To establish radioimmunoassay (RIA) systems of 3,5,3'-triiodo-L-thyronine (T 3 ) and thyroxine (T 4 ), various experiments such as 125 I labelling, antibody raising, preparation of hormone-free sera and efficient separations of the free hormones from those of antibody bound etc. were conducted. By optimizing many factors, assay systems were successfully established. Some detailed methodological aspects were described. (author)

Antibodies immobilized on magnetic particles for radioimmunoassay and immunoradiometric assay of hormones. Final report of a co-ordinated research programme 1991-1995

International Nuclear Information System (INIS)

1996-11-01

The IAEA organized a co-ordinated research programme (CRP) in 1991 for studying the properties of a few most promising magnetizable immunoadsorbents and standardizing some important radioimmunoassay and immunoradiometric assay procedures using them with the ultimate aim of expanding the application of these assays in developing countries using indigenously prepared reagents. Ten laboratories from nine countries of Asia, Latin America and Europe participated in this CRP which was concluded in 1995. Three different magnetizable particles prepared and investigated by the participants, namely magnetite, magnetite coated with silane and magnetite coated with polyacrolein, have emerged suitable for use in radioimmunometric assays from this CRP. Methods have been developed for coupling antibodies to these particles and using the resultant immunoadsorbents for assaying several important hormones and proteins including T 3 , T 4 , fT 3 , fT 4 , reverse T 3 , TSH, thyroglobuling(Tg), Tg-antibodies, HCG, LH, cortisol, FSH and prolacting. All the participating laboratories could develop in house methodology for solid phase assays based on magnetizable particles during the course of the CRP and benefit from the exchange of materials, information and experience amongst them. This report includes detailed results obtained by the participating laboratories as well as a summary and assessment of the achievements of the CRP. It also includes suggestions for areas of investigation for pursuing in the future. Refs, figs, tabs

Free thyroid hormones in patients with severe non-thyroidal illness

Energy Technology Data Exchange (ETDEWEB)

Boettger, I.; Schneck, H.W.

1985-11-01

Free thyroid hormone radioligand assays and indirect methods for FT/sub 4/ and FT/sub 3/ were applied to measurement in sera of patients with severe NTI (hemodialysis, intensive-care, polytrauma). FT/sub 4/ by different techniques was low-normal to decreased by a kinetic two-tube and a T/sub 4/-analogue tracer single-tube assay whereas another two-tube technique measured normal to low-normal but in some instances increased FT/sub 4/ levels. Indirect parameters behaved in a similar fashion. FT/sub 3/ was decreased in most of the cases as were the indirect parameters, mostly due to affected T/sub 4/-T/sub 3/ conversion. Direct and indirect parameters for free thyroid hormones changed in parallel also during follow-up of NTI. There was no clear protein or albumen effect upon the two-tube FT/sub 4/ and the two-tube FT/sub 3/ assay(s). Supersensitively determined basal TSH was found to be decreased in some cases with severe NTI (polytrauma). The findings taken together are consistent with (pseudo) sedondary hypothyroidism in severe NTI. The data show the free thyroid hormone assays tested to be rather reliable with little or no disturbance by severe NTI or specifically hypoalbumenemia.

New aspects of radioimmunochemical measurement of human parathyroid hormone using the labelled antibody technique

International Nuclear Information System (INIS)

Hesch, R.D.; McIntosh, C.H.S.; Woodhead, J.S.; Welsh National School of Medicine, Cardiff

1975-01-01

Two forms of heterogeneity of parathyroid hormone (PTH) have given rise to conflicting results: one due to the heterogeneity of the secreted species from the gland and their peripheral metabolism and the other representing the immunochemical heterogeneity of the available antibodies. We have developed sequence specific assays using the technique of labelled antibodies. Therefore, results of assays measuring the C-terminal part and the (1-34)-N-terminal part of the molecule could be compared to those of an assay for hormone bearing both N- and C-terminal antigenic determinants. This assay is supposed to detect predominantly (1-84)-intact hormone. The immunoradiometric assay of (1-34)-PTH has a sensitivity of 0.04 ng/ml. This technique avoids the critical iodination of the hormone fragment containing no tyrosine. There is the expected overlap between normal subjects and patients with primary and secondary hyperparathyroidism. The most important finding are results from patients undergoing neck catheterization. We demonstrated nonuniform secretion of different species of PTH by parathyroid adenomata and normal glands. This supports the hypothesis of cleavage of the (1-84)-molecule in the gland. (orig.) [de

We don't look at hormones the way we used to

International Nuclear Information System (INIS)

Odell, W.D.

1978-01-01

Our concepts of hormone quantification or assessment have evolved through four different viewpoints during the past 25 years. Initially, we viewed hormones with monocular vision - via bioassay. As bioassay techniques became sophisticated, discrepancies in potencies arose; two or more different potencies existed for an unknown hormone or analyte and a reference preparation depending seemingly on different bioassays. No way to ascertain which was correct existed. Subsequently, binocular vision developed with the existence of immunoassay techniques. Initially, efforts were directed to validate immunoassays and show they gave potencies similar to bioassays. Later, striking discrepancies developed and it was recognized that the two techniques need not agree. Immunoassays recognized structure, bioassays recognized a biological function. A third viewpoint developed with the advent of receptor assays. These assays depended on binding to cellular receptors, but did not involve parameters of in-vivo distribution, degradation, etc. Examples of three or more different potencies appeared for the same substance; one with bioassays, one with immunoassays, and one with receptor assays; all three different answers could be correct. Currently, a fourth viewpoint exists - structure-function analysis. Here the many molecular forms of single hormones may be defined and quantified and often discrepancies in answers in the four viewpoints of hormone quantification can be explained. (author)

Rapid purification of radioiodinated peptides with Sep-Pak reversed phase cartridges and HPLC

International Nuclear Information System (INIS)

Miller, J.J.; Schultz, G.S.; Levy, R.S.

1984-01-01

A simple, rapid method is described for the purification of radioiodinated peptides for use in radioimmuno- and in radioreceptor assays. Iodinated reaction mixtures are applied directly onto Sep-Pak disposable, reversed phase cartridges equilibrated with phosphate buffer. Unreacted 125-iodide and other non-peptide reaction components are eluted with buffer. The peptide fraction is then eluted with 70% buffer:30% acetonitrile. The peptide fraction is further purified by reversed phase high pressure liquid chromatography to separate the native peptide and the mono- and diiodo-derivatives. In this study the method is used to prepare 125-iodide-labeled monoiodo-leucine enkephalin and monoiodo-angiotensin II, which are free of the parent peptides and diiodo-derivatives and are of maximum obtainable specific radioactivity. The usefulness of these labeled peptides in radioimmuno- and radioreceptor assays is demonstrated by their binding to specific antibodies and receptors, respectively. (author)

Comparison of in vitro hormone activities of novel flame retardants TBB, TBPH and their metabolites TBBA and TBMEPH using reporter gene assays.

Science.gov (United States)

Klopčič, Ivana; Skledar, Darja Gramec; Mašič, Lucija Peterlin; Dolenc, Marija Sollner

2016-10-01

The anti-androgenic and anti-thyroid hormonal activities of the two novel brominated flame retardants, TBB and TBPH and of their metabolites TBBA and TBMEPH have been compared using the luciferase reporter gene assays. Only the parent compounds TBB and TBPH exhibited anti-glucocorticoid activity with IC50 values of 1.9 μM and 0.3 μM. Furthermore, mode of action for these two compounds is by direct competing to the glucocorticoid receptor (GR) with IC50 values of 0.03 μM and 0.002 μM. All four tested compounds possess anti-androgenic and anti-thyroid hormonal activities, without agonist activities on the respective receptors. Anti-androgenic activities with IC50 values of 43.5 μM, 0.1 μM, 47.5 μM and 1.3 μM were found for TBB, TBPH, TBBA and TBMEPH. The anti-thyroid hormonal IC50 values of 37.5 μM, 0.1 μM, 22.8 μM and 32.3 μM for TBB, TBPH, TBBA and TBMEPH, together with the above quoted results, indicate that metabolism can modify anti-androgenic, anti-glucocorticoid and anti-thyroid hormonal effects of these novel brominated flame retardants. Furthermore, the parent flame retardants are shown to be able to disrupt the function of the GR as antagonists by direct competition to the receptor. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immunoreactive somatomedin A in human serum

International Nuclear Information System (INIS)

Hall, K.; Brandt, J.; Enberg, G.; Fryklund, L.

1979-01-01

A RIA has been developed for somatomedin A (SM-A) utilizing Sepharose-bound antibodies. This assay, measuring SM-A, the insulin-like growth factors 1 and 2, and somatomedin C, allows determination in serum samples. In comparison with a serum standard, the mean serum levels in patients with acromegaly or GH deficiency and healthy subjects were 8.7 +- 0.7 (n=25), 0.24 +- 0.02 (n=25), and 1.15 +- 0.11 U/ml, respectively. The correlation coefficient between immunoreactive SM-A and SM-A by radioreceptor assay was highly significant (r=0.93), although the potency ratio of SM-A between the two groups of patients was higher in the RIA than in the radioreceptor assay. Gel chromatography revealed that SM-A in acromegalic serum is bound to a carrier protein which is absent in patients with GH deficiency. After gel chromatography at low pH, 90% of applied immunoreactive SM-A was recovered in the low molecular weight fraction and consisted mainly of neutral polypeptides

Clinical evaluation of thyrotropin-releasing hormone (TRH) test with a sensitive immunoradiometric thyrotropin (TSH) assay kit

International Nuclear Information System (INIS)

Nakamura, Saeko; Demura, Reiko; Yamanaka, Yukako; Ishiwatari, Naoko; Jibiki, Kazuko; Odagiri, Emi; Demura, Hiroshi

1987-01-01

Thyrotropin-releasing hormone (TRH) test was performed using a commercially available immunoradiometric thyrotropin (TSH) assay kit (RIA-gnost hTSH) in patients with endocrine diseases. The basal serum concentration of TSH ranged from 0.2 to 2.9 μU/ml in healthy subjects. The values for endocrine diseases, except for Graves' disease, were almost within the normal range. A significant increase in TSH values caused by TRH test was observed in females compared with males (4.4 - 24.7 μU/ml vs 4.1 - 12.3 μU/ml). In cases of Graves' disease, there was a good correlation between the basal TSH value and the response of TSH to TRH. However, in the other endocrine diseases, including acromegaly, prolactinoma, anorexia nervosa, Cushing syndrome, and hypopituitarism, the response of TSH to TRH did not necessarily correlated with the basal TSH value. TRH test would be of value in elucidating pathophysiologic features, as well as in accurately diagnosing secretion reserve of TSH. (Namekawa, K.)

Clinical evaluation of thyrotropin-releasing hormone (TRH) test with a sensitive immunoradiometric thyrotropin (TSH) assay kit

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Saeko; Demura, Reiko; Yamanaka, Yukako; Ishiwatari, Naoko; Jibiki, Kazuko; Odagiri, Emi; Demura, Hiroshi

1987-10-01

Thyrotropin-releasing hormone (TRH) test was performed using a commercially available immunoradiometric thyrotropin (TSH) assay kit (RIA-gnost hTSH) in patients with endocrine diseases. The basal serum concentration of TSH ranged from 0.2 to 2.9 ..mu..U/ml in healthy subjects. The values for endocrine diseases, except for Graves' disease, were almost within the normal range. A significant increase in TSH values caused by TRH test was observed in females compared with males (4.4 - 24.7 ..mu..U/ml vs 4.1 - 12.3 ..mu..U/ml). In cases of Graves' disease, there was a good correlation between the basal TSH value and the response of TSH to TRH. However, in the other endocrine diseases, including acromegaly, prolactinoma, anorexia nervosa, Cushing syndrome, and hypopituitarism, the response of TSH to TRH did not necessarily correlated with the basal TSH value. TRH test would be of value in elucidating pathophysiologic features, as well as in accurately diagnosing secretion reserve of TSH. (Namekawa, K.).

Improved radioimmunoassay for thyroid hormone and reagent

International Nuclear Information System (INIS)

1980-01-01

Improvements in the radioimmunoassay of the thyroid hormones, thyroxine or triiodothyronine, are described. Hydrolyzed cross-linked polyacrylamide particles covalently bonded against the thyroid hormone are employed as solid phase substrates for the thyroid hormone antibodies. The polyacrylamide particles are dyed yellow or blue to facilitate the various manipulative steps during the radioimmunoassay. The particles are characterized by their ability to form stable hydrophilic suspensions. As a result the reaction mixture, during which thyroid hormone is separated from serum proteins and competitive binding in the presence of radioactive tracer with the antibody occurs, requires no agitation to maintain the desired homogeneous condition. This is in contrast to the settling problems experienced with cellulose, dextran and glass particles. In addition, the non-specific binding property of the polyacrylamide particles is so low that the initially separated solid phase particles following incubation can be directly measured for radioactivity levels without any initial washings thus increasing the speed and convenience of the assay procedure. Details of the preparation of the dyed, hydrolyzed polyacrylamide particles, the coupling of antiserum to these particles and the radioimmunoassay procedure are given. Data obtained from the radioimmunoassays of hypothyroid, euthyroid and hyperthyroid sera demonstrated the satisfactory performance of the assay. (U.K.)

A half-century of studies of growth hormone insensitivity/Laron syndrome: A historical perspective.

Science.gov (United States)

Rosenbloom, Arlan L

2016-06-01

A growth hormone (GH) dependent substance responsible for sulfate uptake by costal cartilage of hypophysectomized rats, labeled sulfation factor, was reported in 1957. In 1962 the radioimmunoassay for GH was described. The clinical picture of severe GH deficiency but with high serum concentrations of GH was reported in 3 siblings in 1966 and followed by a 1968 report of 22 patients belonging to 14 consanguineous oriental Jewish families in Israel. Defective sulfation factor generation was demonstrated in 15 of these individuals and in a 1971 report; FFA response to IV GH and growth response to GH injections suggested competitive saturation of peripheral tissue receptors by an abnormal GH. However, studies published in 1973 demonstrated normal fractionation of their circulating GH, and normal binding of GH from 22 patients to various antisera used for radioimmunoassay. In 1976, the Israeli investigators reported that circulating GH from 7 patients reacted normally in the recently developed radioreceptor assay for GH. In 1984, using hepatic microsome pellets, they demonstrated that the defect was a failure of GH binding to receptors. Characterization of the human GH receptor (GHR) gene, reported in 1989, included the initial description of a genetic defect of the GHR in 2 of 9 Israeli patients. At about the same time began the identification in Ecuador of what was to become the largest population of GH insensitivity in the world, ~100 individuals, and the only substantial population with a common mutation of the GH receptor. Treatment studies with recombinant IGF-I began in 1990. Growth response was modest compared to that of GH treated GH deficient subjects. The spectrum of GH insensitivity has expanded beyond GH receptor deficiency to include postreceptor abnormalities: IGF-I gene mutation (1996); IGF-I receptor mutation (2003); signal transducer and activator of transcription 5b mutation (2003); and mutation of the GH-dependent acid labile subunit (2004). Rare

Comparative assessment of quality of immunoradiometric assay (IRMA) and chemiluminescence immunometric assay (CHEIMA) for estimation of thyroid stimulating hormone (TSH)

International Nuclear Information System (INIS)

Sajid, K.M.

2009-01-01

Biological substances like hormones, vitamins and enzymes are found in minute quantities in blood. Their estimation requires very sensitive and specific methods. The most modern method for estimation of thyroid stimulating hormone in serum is non-isotopic enzyme enhanced chemiluminescence immunometric method. In our laboratory immunoradiometric assay is in routine for the last many years. Recently interest has grown to establish non-isotopic techniques in laboratories of PAEC. However, the main requirement to adopt the new procedures is to compare their results, cost and other benefits with the existing method. Immunoassay laboratory of MINAR, therefore, conducted a study to compare the two methods. A total of 173 (males: 34 females: 139 age: between 1 and 65 years) cases of clinically confirmed thyroid status were included in the study. Serum samples of these cases were analyzed by two methods and results were compared by plotting precision profiles, correlation plots and calculating sensitivities and specificities of the methods. As the results in all the samples were not normally distributed Wilcoxon rank sum test was applied to compare the analytical results of two methods. The comparison shows that the results obtained in two methods are not completely similar (p=0.0003293), although analysis of samples in groups shows that some similarity exists between the results of hypo and hyperthyroid patients (p<=0.156 and p<=0.6138). This shows that results obtained in these two methods could sometimes disagree in final diagnosis. Although TSH-CHEIMA is analytically more sensitive than TSH-IRMA the clinical sensitivities and specificities of two methods are not significantly different. TSH-CHEIMA test completes in almost 2 hours whereas TSH-IRMA takes about 6 hours to complete. Comparison of costs shows that TSH-CHIEMA is almost 5 times more expensive than TSH-IRMA. We conclude that the two methods could sometimes disagree but the two techniques have almost same

Effects of zinc on male sex hormones and semen quality in rats

African Journals Online (AJOL)

olayemitoyin

collected and assayed for Luteinizing hormone (LH), follicle stimulating hormone (FSH), Prolactin (PL), testosterone (T), progesterone .... a role in the production, storage and secretion of .... This study was done to assess the effects of oral zinc.

A national quality control scheme for serum HGH assays

International Nuclear Information System (INIS)

Hunter, W.M.; McKenzie, I.

1979-01-01

In the autumn of 1975 the Supraregional Assay Service established a Quality Control Sub-Committee and the intra-laboratory QC Scheme for Growth Hormone (HGH) assays which is described here has served, in many respects, as a pilot scheme for protein RIA. Major improvements in accuracy, precision and between-laboratory agreement can be brought about by intensively interactive quality control schemes. A common standard is essential and should consist of ampoules used for one or only a small number of assays. Accuracy and agreement were not good enough to allow the overall means to serve as target values but a group of 11 laboratories were sufficiently accurate to provide a 'reference group mean' to so serve. Gross non-specificity was related to poor assay design and was quickly eliminated. Within-laboratory between-batch variability was much worse than that normally claimed for simple protein hormone RIA. A full report on this Scheme will appear shortly in Annals of Clinical Biochemistry. (Auth.)

Proceedings of the 13. Annual meeting of the Federation of Societies on Experimental Biology; 23. Brazilian congress on biophysics; 30. Brazilian congress on pharmacology and experimental therapeutics; 33. Brazilian congress on physiology; 14. Brazilian congress on clinical research; 22. Brazilian congress on neuroscience and behaviour. Abstracts

International Nuclear Information System (INIS)

1998-01-01

Several aspects concerning neuroscience and behavior, compared physiology, endocrinology, pharmacology, molecular immunology and immuno diagnosis, biochemistry, genetic and toxicology of either animals, plants and microorganisms are studied. Topics such as cell membrane structures (including receptors), enzymatic assays, biological pathways, structural chemical analysis, metabolism, biological functions, blood pressure regulation are focused. The use of radiolabelled compounds, e.g. radioassay, radioimmunoassay, radioreceptor assay, are the most applied techniques

Proceedings of the 13. Annual meeting of the Federation of Societies on Experimental Biology; 23. Brazilian congress on biophysics; 30. Brazilian congress on pharmacology and experimental therapeutics; 33. Brazilian congress on physiology; 14. Brazilian congress on clinical research; 22. Brazilian congress on neuroscience and behaviour. Abstracts; Anais do 13. Reuniao anual da Federacao de Sociedades de Biologia Experimental; 23. Congresso brasileiro de biofisica; 30. Congresso brasileiro de farmacologia e terapeutica experimental; 33. Congresso brasileiro de fisiologia; 14. Congresso brasileiro de investigacao clinica; 22. Congresso brasileiro de neurociencias e comportamento. Resumos

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-07-01

Several aspects concerning neuroscience and behavior, compared physiology, endocrinology, pharmacology, molecular immunology and immuno diagnosis, biochemistry, genetic and toxicology of either animals, plants and microorganisms are studied. Topics such as cell membrane structures (including receptors), enzymatic assays, biological pathways, structural chemical analysis, metabolism, biological functions, blood pressure regulation are focused. The use of radiolabelled compounds, e.g. radioassay, radioimmunoassay, radioreceptor assay, are the most applied techniques.

Multiplex Immunoassay Profiling of Hormones Involved in Metabolic Regulation.

Science.gov (United States)

Stephen, Laurie; Guest, Paul C

2018-01-01

Multiplex immunoassays are used for rapid profiling of biomarker proteins and small molecules in biological fluids. The advantages over single immunoassays include lower sample consumption, cost, and labor. This chapter details a protocol to develop a 5-plex assay for glucagon-like peptide 1, growth hormone, insulin, leptin, and thyroid-stimulating hormone on the Luminex ® platform. The results of the analysis of insulin in normal control subjects are given due to the important role of this hormone in nutritional programming diseases.

Reproductive hormones disorders of Sudanese females using immunoradiometric assay (IRMA)

International Nuclear Information System (INIS)

Ali, N. I.; Almahi, W. A. A.; Abdalla, O. M.; Bafarag, S. M. I.; Abdelgadir, O. M.; Eltayeb, M. A. H.; Hassan, A. M. E.; Hassan, A. M. E.

2004-12-01

In this study fertility hormones were measured for 587 infertile Sudanese female referred from gynecological clinics. The ages of these female ranges from 16-50 years divided into seven groups. Eighty seven percent of them are in the age range between 21 and 40 year which correlate with the female's fertile period and 5.6% of them under 20 years. Sensitive (IRMA) method was used for measuring the hormone concentration. The objective of this study was to found out the percentage of hormonal disorders and its relation to the age in infertile Sudanese females. The age group (21-25) was the most affected group by the Poly Cystic Ovary Syndrome (PCOS) and represented 5.1% of the total number of patients. The least group was the age group (41-45) with a percentage of 0.4. The LH and the FSH in the age group of (31-35) was found to be higher than the other groups and represented 11.4% and 7.8% from the total number of patients respectively. The least percent of high level of LH and FSH was found to be in the most fertile age group (15-20) and it was 1.7% and 1.0% from the total number of studied patient, respectively. Those who were in the age range (26-30) with hyperprolactinaemia represented 10.4% of patients, while those with age rang (46-50) with hyperprolactinaemia represented the lowest percentage (1.2%). The percentage of patients having high LH and high FSH was 44.5% and 29.1% respectively, while the hyperprolactinaemia among the infertile Sudanese female was found to 38.2%.(Author)

Immunohistochemical localisation and developmental aspects of epidermal growth factor in the rat

DEFF Research Database (Denmark)

Raaberg, L; Nexø, E; Damsgaard Mikkelsen, J

1988-01-01

The tissue localisation and time of first appearance of Epidermal Growth Factor (EGF) in the developing rat were investigated by means of immunohistochemistry, radioimmunoassay and radioreceptor assay. In this study we were able to show, that EGF appears prenatally in the lung and the kidney from...

Suppression of Thyroid Hormone Receptor-Mediated Transcription ...

African Journals Online (AJOL)

TH)-induced TR-mediated transcription. We further examined the effects of methamidophos on TR-thyroid hormone response element (TRE) binding using the liquid chemiluminescent DNA pull-down assay (LCDPA), and found no dissociation of ...

PTH Assays: Understanding What We Have and Forecasting What We Will Have

Directory of Open Access Journals (Sweden)

Jose Gilberto H. Vieira

2012-01-01

Full Text Available Parathyroid hormone (PTH assays have evolved continuously for the last 50 years. Since the first radioimmunoassay was described in 1963, several assays based on immunological identification have been published (first generation assays. The routine assays used nowadays are immunometric “sandwich-type”. They are based on two different monoclonal antibodies, one amino-terminal and the other carboxyl terminal specific. These second generation assays are widely available and adapted to most of the automation platforms. The specificity of the amino terminal antibody defines if the immunometric assay measures only the bioactive PTH circulating form (including the first amino terminal amino acids or the “intact” PTH, which includes, besides bioactive PTH, other “long” carboxyl-terminal forms, for example, 7–84-PTH. Assays for “intact” PTH are the most commonly available and the potential advantage of the bioactive PTH assays is still debatable. Next generation of assays will be based on different principles, mainly mass spectrometry in samples submitted to a prior purification and fragmentation steps. These assays will provide information about the whole spectra of PTH peptides in circulation, with a significant increase of the information regarding this biologically important peptide hormone.

Expression of the epidermal growth factor receptor in human small cell lung cancer cell lines

DEFF Research Database (Denmark)

Damstrup, L; Rygaard, K; Spang-Thomsen, M

1992-01-01

of EGF receptor mRNA in all 10 cell lines that were found to be EGF receptor-positive and in one cell line that was found to be EGF receptor-negative in the radioreceptor assay and affinity labeling. Our results provide, for the first time, evidence that a large proportion of a broad panel of small cell......Epidermal growth factor (EGF) receptor expression was evaluated in a panel of 21 small cell lung cancer cell lines with radioreceptor assay, affinity labeling, and Northern blotting. We found high-affinity receptors to be expressed in 10 cell lines. Scatchard analysis of the binding data...... demonstrated that the cells bound between 3 and 52 fmol/mg protein with a KD ranging from 0.5 x 10(-10) to 2.7 x 10(-10) M. EGF binding to the receptor was confirmed by affinity-labeling EGF to the EGF receptor. The cross-linked complex had a M(r) of 170,000-180,000. Northern blotting showed the expression...

Prognostic Utility of the 21-Gene Assay in Hormone Receptor–Positive Operable Breast Cancer Compared With Classical Clinicopathologic Features

Science.gov (United States)

Goldstein, Lori J.; Gray, Robert; Badve, Sunil; Childs, Barrett H.; Yoshizawa, Carl; Rowley, Steve; Shak, Steven; Baehner, Frederick L.; Ravdin, Peter M.; Davidson, Nancy E.; Sledge, George W.; Perez, Edith A.; Shulman, Lawrence N.; Martino, Silvana; Sparano, Joseph A.

2008-01-01

Purpose Adjuvant! is a standardized validated decision aid that projects outcomes in operable breast cancer based on classical clinicopathologic features and therapy. Genomic classifiers offer the potential to more accurately identify individuals who benefit from chemotherapy than clinicopathologic features. Patients and Methods A sample of 465 patients with hormone receptor (HR) –positive breast cancer with zero to three positive axillary nodes who did (n = 99) or did not have recurrence after chemohormonal therapy had tumor tissue evaluated using a 21-gene assay. Histologic grade and HR expression were evaluated locally and in a central laboratory. Results Recurrence Score (RS) was a highly significant predictor of recurrence, including node-negative and node-positive disease (P < .001 for both) and when adjusted for other clinical variables. RS also predicted recurrence more accurately than clinical variables when integrated by an algorithm modeled after Adjuvant! that was adjusted to 5-year outcomes. The 5-year recurrence rate was only 5% or less for the estimated 46% of patients who have a low RS (< 18). Conclusion The 21-gene assay was a more accurate predictor of relapse than standard clinical features for individual patients with HR-positive operable breast cancer treated with chemohormonal therapy and provides information that is complementary to features typically used in anatomic staging, such as tumor size and lymph node involvement. The 21-gene assay may be used to select low-risk patients for abbreviated chemotherapy regimens similar to those used in our study or high-risk patients for more aggressive regimens or clinical trials evaluating novel treatments. PMID:18678838

Prognostic utility of the 21-gene assay in hormone receptor-positive operable breast cancer compared with classical clinicopathologic features.

Science.gov (United States)

Goldstein, Lori J; Gray, Robert; Badve, Sunil; Childs, Barrett H; Yoshizawa, Carl; Rowley, Steve; Shak, Steven; Baehner, Frederick L; Ravdin, Peter M; Davidson, Nancy E; Sledge, George W; Perez, Edith A; Shulman, Lawrence N; Martino, Silvana; Sparano, Joseph A

2008-09-01

Adjuvant! is a standardized validated decision aid that projects outcomes in operable breast cancer based on classical clinicopathologic features and therapy. Genomic classifiers offer the potential to more accurately identify individuals who benefit from chemotherapy than clinicopathologic features. A sample of 465 patients with hormone receptor (HR) -positive breast cancer with zero to three positive axillary nodes who did (n = 99) or did not have recurrence after chemohormonal therapy had tumor tissue evaluated using a 21-gene assay. Histologic grade and HR expression were evaluated locally and in a central laboratory. Recurrence Score (RS) was a highly significant predictor of recurrence, including node-negative and node-positive disease (P < .001 for both) and when adjusted for other clinical variables. RS also predicted recurrence more accurately than clinical variables when integrated by an algorithm modeled after Adjuvant! that was adjusted to 5-year outcomes. The 5-year recurrence rate was only 5% or less for the estimated 46% of patients who have a low RS (< 18). The 21-gene assay was a more accurate predictor of relapse than standard clinical features for individual patients with HR-positive operable breast cancer treated with chemohormonal therapy and provides information that is complementary to features typically used in anatomic staging, such as tumor size and lymph node involvement. The 21-gene assay may be used to select low-risk patients for abbreviated chemotherapy regimens similar to those used in our study or high-risk patients for more aggressive regimens or clinical trials evaluating novel treatments.

Immunoradiometric assay for the determination of E. coli proteins in recombinant dna derived human growth hormone produced at IPEN-CNEN/SP

International Nuclear Information System (INIS)

Soares, Carlos R.J.

1995-01-01

An immunoradiometric assay (IRMA) for the determination of multiple antigens was set up in order to quantify E. coli (ECP) in lots of purified recombinant human growth hormone (rec-hGH). SDS-PAGE and Western Blotting techniques were carried out, in parallel, to confirm the results obtained by IRMA and to provide more information about the contaminants. Anti-ECP antibodies were obtained by rabbit immunization with ECP, which were submitted to the same purification process utilized for rec-hGH with the exception of the last step. A strain-process-specific assay was thus set up. The antiserum obtained was purified through an affinity column prepared with the same ECP used for immunization, this provided an highly sensitive assay (0,03 ng ECP/mL). This IRMA was shown to be specific, not presenting any cross reaction with hGH and studies carried out on precision, accuracy and linearity of response with dilution confirmed its validity as one of the fundamental purity tests for rec-hGH produced at IPEN-CNEN/SP, whose principles can be easily extended to the analysis of other similar products. These studies have also shown that the utilization of an affinity column, prepared with the described anti-ECP antiserum was very effective, providing rec-hGH lots with less then 10 parts per million (0,001%) of contaminating proteins. (author). 45 refs., 15 figs., 11 tabs

Receptor scintigraphy using the Tc-99M-labelled somatostatin analogue EDDA-TRYCINE-HYNIC-TOC: clinical results in different tumor types and comparison with In-111 DOTATOC during Y-90 DOTATOC radioreceptor therapy

International Nuclear Information System (INIS)

Baum, R.P.; Schmuecking, M.; Fischer, S.; Przetak, C.; Niesen, A.; Maecke, H.R.

2002-01-01

Aim: To evaluate Tc-99m EDDA-TRYCINE-HYNIC-TOC in patients with somatostatin receptor positive tumours (staging, pre-therapeutic dosimetry for radioreceptor therapy and restaging after therapy) in comparison with In-111 DOTATOC. Material and Methods: The Tc-99m labelled somatostatin analogue was synthesized by an optimized procedure in our pharmaceutical laboratory using lyophilized kits (radiochemical purity by HPLC, TLC > 95%, product stability in vitro 4 to 6h). So far, 58 patients (60 examinations) were studied after injection of 580-890 MBq (median 673 MBq) EDDA-TRYCINE-HYNIC-TOC. The histologically proven tumours were neuroendocrine neoplasias, renal carcinomas, bronchial carcinoma, mesothelioma and malignant fibrous histiocytoma. The imaging protocol consisted of whole-body scans and planar images of the tumor region (15 min, 1 h, 2 h, 4 h, 8 h, 24 h p.i.) and additionally SPECT-images (1 h und 4 h p.i.). For semi-quantitative assessment, individual regions of interest (ROI) were drawn in order to generate time-activity curves and to calculate tumour-to-tissue/background ratios which were compared by visual grading (scala 0 to 3+). Furthermore, pharmacokinetic analyses were carried out (radioactivity kinetics in plasma and urine). In some selected patients, image fusion of whole-body scans was performed with CT and/or MRT and/or PET using a NUD software and a HERMES computer. Results: 10 out of 58 patients showed an intense tracer accumulation in the SSTR-positive tumours (visual 3+, tumour/background ratio >2,5). In these patients, radioreceptor therapy was carried out using Y-90 DOTATOC (simultaneous injection von 150 MBq In-111 DOTATOC). All pretherapeutic scans with the Tc-99m labelled ligand (4 h p.i.) showed a similar overall pattern of biodistribution and tumour uptake in comparison to the therapy scans with In-111 / Y-90 DOTATOC (24 h p.i.). The Tc-99m EDDA-TRYCINE-HYNIC-TOC scans (incl. SPECT) offered superior imaging properties with earlier tumour

Dual isotope assays

International Nuclear Information System (INIS)

Smith, G.F.W.; Stevens, R.A.J.; Jacoby, B.

1980-01-01

Dual isotope assays for thyroid function are performed by carrying out a radio-immunoassay for two of thyroxine (T4), tri-iodothyronine (T3), thyroid stimulating hormone (TSH), and thyroxine binding globulin (TBG), by a method wherein a version of one of the thyroid components, preferably T4 or T3 is labelled with Selenium-75 and the version of the other thyroid component is labelled with a different radionuclide, preferably Iodine-125. (author)

Tumor markers kits development for use in radioimmunometric assays

International Nuclear Information System (INIS)

Ahmed, B.

1997-01-01

The immunoassays such as RIA and IRMA are now widely used through the world for the quantitation of a variety of substances in the biological fluid for their high sensibility and specificity which required simple equipments. These techniques are also very used in Algeria for an effective amelioration of public heath The assays kits of RIA/IRMA of thyroid hormones are the most used, followed by peptidic hormones, steroids hormones and IRMA Tumor Markers (T.M) kits. In spite of the important demand, of tumor markers kits for the diagnosis and follow up of cancers their use are always insufficient due to the high cost. The research contract programme proposed by IAEA on the theme 'The Developments of IRMA Tumor Markers Kits' of prostate specific Antigen (PSA) and Tissue Polypeptide Specific Antigen (TPS) will allowed us to produce locally with best quality-price, the main reagents for PSA and TPS IRMA assays kits for diagnosis and follow up the prostate and breast cancers which are very spready in the country. This report include the following points: Generalities on the use of tumor markers in Algeria, programme for the Development of the PSA IRMA assay (schedule of protocols applied for each reagents; annual planning for assessing the programme activities) and conclusion

Homeorhetic hormones, metabolites and accelerated growth ...

African Journals Online (AJOL)

Blood samples were drawn from surgically implanted catheters in the caudal aorta and vena cava during normal growth, maintenance (zero) growth and accelerated growth.These samples were assayed for glucose, free fatty acids, glycerol, alanine, lysine, growth hormone, insulin and thyroxine. It was found that during the ...

Radioimmunological assay of the biologically active fragment of the human parathyroid hormone

International Nuclear Information System (INIS)

Desplan, C.; Jullienne, A.; Raulais, D.; Rivaille, P.; Barlet, J.P.; Moukthar, M.S.; Milhaud, G.

1977-01-01

The authors describe a RIA of the biologically active fraction (N-terminal) of human parathyroid hormone. This homologous test uses antibodies obtained in goats against a N-terminal 1-34 fragment of hPTH synthetised according to the method of Niall and Coll. In this system, natural hPTH of different origin (extracts from parathyroid adenomas, adenomal culture medium, hyperparathyroid plasma, adsorption chromatography extract of normal human plasma) behaved in the same manner as the synthetic reference hormone 1-34 hPTHN. The RIA detected PTH in 65% of the normal subjects and distinguished the normal values from the values of hyperparathyroid patients, which makes it suitable for clinical practice. (AJ) [de

Clinical significance of determination of serum TRAb levels in patients with thyroid diseases

International Nuclear Information System (INIS)

Wu Lijian; Tang Bing; Yang Chunying; Lin Jun

2005-01-01

Objective: To investigate the clinical Significance of determination of serum thyroid stimulating hormone receptor antibody (TRAb) levels in patients with thyroid diseases, especially in patients with Graves' disease. Methods: Serum TRAb levels were determined with radio-receptor assay (RRA) in 302 patients with various thyroid diseases and 52 controls. Results: In patients with Graves' disease before treatment (n=62) the positive rate of TRAb was 86.3%. In patients with Graves' diseases improved after treatment (n=60), the positive rate was 74.5%; in those clinically cured (n=68) the positive rate was 32.1%. In 58 patients with Graves' disease who relapsed after apparently cure, the positive rate of TRAb rose to 90.3 %. However, there were no positive TRAb cases in 23 patients with simple goiter and 31 patients with benign thyroid adenomas. Also, there were no positive TRAb cases in the controls. Conclusion: TRAb levels correspond well with the severity of Graves' disease. (authors)

Study on the internal quality control of thyroid hormones assays in a hospital laboratory

International Nuclear Information System (INIS)

Hu Haiqiang; Chu Shaolin; Ye Peihong; Lei Qiufang; Chai Luhua; Xia Wei

2004-01-01

Objective: With the aim of providing more reliable information for clinical diagnosis, this study investigated the possible causes of the occasional instability of thyroid hormones (T 3 , T 4 , FT 3 , FT 4 TSH) assays in this laboratory and tried to seek plausible explanation for some seemingly contradictory (mismatching) readings of the laboratory reports. Methods: Regular monitoring and checks were enforced on laboratory equipment from sampling pipet to gamma-counters. Results of separation with PR reagent and solid - phase coated tube were compared for superiority (FT 3 ). Collected specimens were tested in monthly sets; this study consisted of 10 sets with total 964 specimens. Serum T 3 , T 4 , FT 3 , FT 4 levels were measured with RIA. For every hormone tested, values of parameters of the standard cure (B 0 , NSB, a, b, r, ED 20 , ED 50 , ED 80 , ABCV) were recorded in detail, from which the QC (quality control) table was derived. For complementary sake , mean level in patients' sera was noted along with the quality control sera. Shewart control chart was drawn for quick reference. Serum TSH levels were measured with IRMA; the parameters involved were: B 0 NSB, ED 80 , ED 50 , ED 20 , standard point deviation. Results: Among the 964 specimens tested, there were 154 specimens with seemingly contradictory (mismatching) results, of which, the majority (n=145) were not erroneous and were compatible with the clinical manifestations of thyroid dysfunction other than plain simple hyper-or hypothyroidism. Only 9 (5.8% of the 154) were due to technical errors (defective technic in removing the supernatant n=7, lipid blood separated with PR reagent n=2). Conclusion: Faulty technic in separation is the main source of random error. From the data of this laboratory, authors believe that solid-phase separation method is better than the conventional homogenous-phase separation method and is the preferred one. With meticulous adherence to standard laboratory procedures and

The detection of ovulation with a two-hour radioimmunoassay for human plasma luteinizing hormone using the Centria Analyzer

International Nuclear Information System (INIS)

Schwarz, S.

1980-01-01

We describe a rapid (2-h) radioimmunoassay for human plasma luteinizing hormone which utilizes the reagents from a commercially available kit. Standardization of the assay was achieved using plasma standards instead of a buffer system and the Centria radioimmunoassay centrifugal analyzer which allowed simultaneous initiation and termination of reactions in all assay tubes. The specificity, precision, and accuracy of the assay were equal to or better than the conventional 24-h assay. Since this assay is designed to detect the mid-cycle surge of luteinizing hormone, its decreased sensitivity was small price to pay for the speed with which a result could be obtained. (orig.) [de

Anti-idiotypic antibody: A new strategy for the development of a growth hormone receptor antagonist.

Science.gov (United States)

Lan, Hainan; Zheng, Xin; Khan, Muhammad Akram; Li, Steven

2015-11-01

In general, traditional growth hormone receptor antagonist can be divided into two major classes: growth hormone (GH) analogues and anti-growth hormone receptor (GHR) antibodies. Herein, we tried to explore a new class of growth hormone receptor (GHR) antagonist that may have potential advantages over the traditional antagonists. For this, we developed a monoclonal anti-idiotypic antibody growth hormone, termed CG-86. A series of experiments were conducted to characterize and evaluate this antibody, and the results from a competitive receptor-binding assay, Enzyme Linked Immunosorbent Assays (ELISA) and epitope mapping demonstrate that CG-86 behaved as a typical Ab2β. Next, we examined its antagonistic activity using in vitro cell models, and the results showed that CG-86 could effectively inhibit growth hormone receptor-mediated signalling and effectively inhibit growth hormone-induced Ba/F3-GHR638 proliferation. In summary, these studies show that an anti-idiotypic antibody (CG-86) has promise as a novel growth hormone receptor antagonist. Furthermore, the current findings also suggest that anti-idiotypic antibody may represent a novel strategy to produce a new class of growth hormone receptor antagonist, and this strategy may be applied with other cytokines or growth factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interference by antiruthenium antibodies in the Roche thyroid-stimulating hormone assay

NARCIS (Netherlands)

Buijs, M. M.; Gorgels, J. P. M. C.; Endert, E.

2011-01-01

There are many causes of interference in immunoassays causing erratic patient results. A method-specific interference due to antiruthenium antibodies in Roche free thyroxine (fT4) and free triiodothyronine (fT3) assays has been described previously. As a result, a new generation fT4 assay has been

Reproductive Hormones Disorders Of Sudanese Infertile Females Using Immunoradiometric assay (IRMA)

International Nuclear Information System (INIS)

Ali, N. I.; Almahi, W. A. A.; Abdalla, O. M.; Bafarag, S. M. I.; Abdelgadir, O. M.; Eltayeb, M. A. H.; Hassan, A. M. E.; Hassan, A. M. E.

2004-01-01

In this study fertility hormones were measured for 587 infertile Sudanese female referred from gynecological clinics. The ages of these female ranges from 16 - 50 years divided into seven groups. Eighty seven percent of them are in the age range between 21 and 40 year which correlate with the female's fertile period and 5.6% of them under 20 years. Sensitive (IRMA) method was used for measuring the hormone concentration. The objective of this study was to found out the percentage of hormonal disorders and its relation to the age in infertile Sudanese females. The age group (21 - 25) was the most affected group by the Poly-Cystic Ovary Syndrome (PCOS) and represented 5.1% of the total number of patients. The least group was the age group (41- 45) with a percentage of 0.4. The LH and the FSH in the age group of (31- 35) was found to be higher than the other groups and represented 11.4% and 7.8% from the total number of patients respectively. The least percent of high level of LH and FSH was found to be in the most fertile age group (15 - 20) and it was 1.7% and 1.0% from the total number of studied patient, respectively. Those who were in the age range (26 - 30) with hyperprolactinemia represented 10.4% of patients, while those with age range (46 - 50) with hyperprolactinemia represented the lowest percentage (1.2%). The percentage of patients having high LH and high FSH was 44.5% and 29.1% respectively , while the hyperprolactinemia among the infertile Sudanese female was found to 38.2%. (Authors)

Receptor imaging with a new Tc-99m labelled somatostatin analogue (Tc-99m EDDA-TRYCINE-HYNIC-TOC): first clinical results and comparison with In-111 Dotatoc during radioreceptor therapy with Y-90 Dotatoc

International Nuclear Information System (INIS)

Baum, R.P.; Schmuecking, M.; Fischer, S.; Przetak, C.; Niesen, A.; Maecke, H.R.

2002-01-01

Full text: To evaluate Tc-99m EDDA-TRYCINE-HYNIC-TOC (TET-H-TOC) in patients with somatostatin receptor (SSTR)-positive tumors (staging, pretherapeutic indication for radioreceptor therapy and restaging after therapy) in comparison with In-111 DOTATOC. The Tc-99m labelled somatostatin analogue was synthesized by an optimized procedure in our pharmaceutical lab using lyophilized kits (radiochemical purity by HPLC, TLC > 95 %, product stability in vitro 4 to 6 h). So far, 46 patients (53 examinations) were studied after injection of 580-890 MBq (median 673 MBq) TET-H-TOC. The histologically proven tumors were endocrine neoplasias, renal carcinomas, bronchial carcinoma, mesothelioma and malignant fibrous histiocytoma. The imaging protocol consisted of whole-body scans and planar images of the tumor region (15 min, 1 h, 2 h, 4 h, 8 h, 24 h p.i.) and additionally SPECT-images (1 h and 4 h p.i.). For semi-quantitative assessment, individual regions of interest (ROI) were drawn in order to generate time-activity curves and to calculate tumor-to-tissue/background ratios which were compared by visual grading (scale 0 to 3+). Furthermore, pharmacokinetic analyses were carried out (radioactivity kinetics in plasma and urine). In some selected patients, image fusion of the whole-body scans was performed with CT and/or MRT and/or PET using a HERMES computer. 7 out of 46 patients showed an intense tracer accumulation in the SSTR-positive tumors (visual 3+, tumor / background ratio >2,5). In these patients, radioreceptor therapy was carried out using Y-90 DOTATOC (simultaneous injection of 150 MBq In-111 DOTATOC). All pretherapeutic scans with the Tc-99m labelled ligand (4 h p.i.) showed a similar overall pattern of biodistribution and tumor uptake in comparison to the therapy scans with In-111 / Y-90 DOTATOC 24 h p.i. The Tc-99m EDDA-HYNIC-TOC scans (incl. SPECT) offered superior imaging properties with earlier tumor visualization (all lesions were detected 1 h p.i.) as compared

Clinical implications of a new TSH-receptor-antibody-assay (DYNOtest {sup trademark} TRAKhuman) in autoimmune thyroid diseases; Klinische Implikationen eines neuen TSH-Rezeptor-Antikoerper-Assays (DYNOtest {sup trademark} TRAKhuman) bei autoimmunen Schilddruesenerkrankungen

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Meller, J.; Schreivogel, I.; Becker, W. [Goettingen Univ. (Germany). Abt. fuer Nuklearmedizin; Bergmann, A.; Morgenthaler, N. [B.R.A.H.M.S Diagnostica, Berlin (Germany); Huefner, M. [Goettingen Univ. (Germany). Abt. Innere Medizin

2000-07-01

Aim: Conventional radioreceptor-antibody-assays (RAAs) fail in the detection of TSH-receptor antibodies (TRAKs) in 10-30% of patients with Graves' disease (GD). The aim of this study was the evaluation of the diagnostic and clinical impact of a new RRA (DYNOtest {sup trademark} TRAKhuman) which uses the human recombinant TSH-Receptor in the diagnosis of autoimmune thyroid disease. Methods: Sera from 142 consecutive patients (GD: n=50, autoimmune thyroiditis/AIT: n=92) and from 55 controls (31 patients without any thyroid disease and 14 with euthyroid goiter) were evaluated both with the DYNOtest {sup trademark} TRAKhuman-assay and a conventional RRA (TRAK-Assay {sup trademark}). Thyroid in vitro parameters and thyroid sonography were performed in all patients. Results: The DYNOtest {sup trademark} TRAK-assay was significantly superior to the conventional RRA in the diagnosis of GD (p<0,00012), especially in those who were treated by thionamides (p<0,003) and in the diagnosis of TRAK-positive patients with AIT (p<0,003). The majority of TRAK-positive AIT-patients suffered from hypothyroidism. One false positive result in patients with euthyroid goiter was found in the TRAK-Assay {sup trademark} as well as in the DYNOtest {sup trademark} TRAKhuman-Assay. Therefore the specifity of the DYNOtest {sup trademark} TRAKhuman was not inferior compared with the conventional assay. Conclusion: The DYNOtest {sup trademark} TRAK-assay is superior in the diagnostic work up of Graves' disease compared with a conventional TRAK-assay and offers an equal specifity. (orig.) [German] Ziel: Bei konventionellen Radiorezeptor-Antikoerper-Assays (RRAs) misslingt der Nachweis von TSH-Rezeptor Antikoerpern (TRAKS) bei 10-30% der immunogenen Hyperthyreosen (IH). Ziel der Studie war es, den diagnostischen und klinischen Stellenwertes eines neuen RRA (DYNOtest {sup trademark} TRAKhuman) bei autoimmunen Schilddruesenerkrankungen zu evaluieren. Methoden: Serumproben von 142

Radioimmunoassay of human growth hormone and its application in pituitary dysfunction studies

International Nuclear Information System (INIS)

Asolkar, S.V.; Sivaprasad, N.; Shah, K.B.; Mani, R.S.; Deshpande, A.

1981-01-01

A simple, specific and sensitive Radioimmunoassay (RIA) has been developed for the measurement of Human Growth Hormone (HGH) in serum samples. 123 I-labelled HGH has been used as a tracer and dextran coated charcoal system has been employed to separate antibody bound hormone from the unbound one. The assay offers sensitivity of 0.16 ng/ml with a reproducibility of 7% intraassay and inter-assay variations. Serum HGH levels were measured at fasting-resting state and during insulin stimulation test in (1) 15 normal subjects (controls) and (2) 31 patients with stunted growth, whereas (3) in 7 acromegalic patients the same were measured at fasting-resting state and after oral glucose administration. This procedure has been used to distinguish dwarfs due to growth hormone deficiency from other conditions unrelated to pituitary disease and to confirm acromegaly. (author)

Effects of estradiol and progesterone on the variability of the micronucleus assay

International Nuclear Information System (INIS)

Baeyens, Ans; Vandersickel, Veerle; Thierens, Hubert; Ridder, Leo De; Vral, Anne

2005-01-01

To investigate chromosomal radiosensitivity of lymphocytes the micronucleus (MN) assay has been used for many years. The results of these studies suggest the use of the MN assay as a biomarker for cancer predisposition. However, the MN assay has still some limitations associated with the reproducibility and sensitivity. Especially a high intra-individual variability has been observed. An explanation for this high intra-individual variability is not yet available. In literature it is suggested that the high variability among females is attributable to hormonal status. In this study we investigated if the high intra-individual variability in micronucleus formation in lymphocytes of females after in vitro exposure to ionising radiation is caused by variations in hormone levels of estradiol (E2) and progesterone (PROG). For this, the MN assay was performed on blood samples of 18 healthy women during 7 consecutive weeks while the estradiol and progesterone levels were determined at the same time. The MN assay was also examined in cultures of isolated blood lymphocytes with estradiol or progesterone levels added in vitro. The results demonstrated that estradiol and progesterone levels have no influence on the variations in radiation-induced MN yields observed in blood samples of healthy women. These conclusions were confirmed by the 'in vitro' experiments as no correlation between the MN yields and the concentrations of hormones (estradiol or progesterone) added in vitro to isolated lymphocytes cultures was observed

Concordance of self-reported hormonal contraceptive use and presence of exogenous hormones in serum among African women.

Science.gov (United States)

Pyra, Maria; Lingappa, Jairam R; Heffron, Renee; Erikson, David W; Blue, Steven W; Patel, Rena C; Nanda, Kavita; Rees, Helen; Mugo, Nelly R; Davis, Nicole L; Kourtis, Athena P; Baeten, Jared M

2018-04-01

Studies that rely on self-report to investigate the relationship between hormonal contraceptive use and HIV acquisition and transmission, as well as other health outcomes, could have compromised results due to misreporting. We determined the frequency of misreported hormonal contraceptive use among African women with and at risk for HIV. We tested 1102 archived serum samples from 664 African women who had participated in prospective HIV prevention studies. Using a novel high-performance liquid chromatography-mass spectrometry assay, we quantified exogenous hormones for injectables (medroxyprogesterone acetate or norethisterone), oral contraceptives (OC) (levonorgestrel or ethinyl estradiol) and implants (levonorgestrel or etonogestrel) and compared them to self-reported use. Among women reporting hormonal contraceptive use, 258/358 (72%) of samples were fully concordant with self-report, as were 642/744 (86%) of samples from women reporting no hormonal contraceptive use. However, 42/253 (17%) of samples from women reporting injectable use, 41/66 (62%) of samples from self-reported OC users and 3/39 (8%) of samples from self-reported implant users had no quantifiable hormones. Among self-reported nonusers, 102/744 (14%) had ≥1 hormone present. Concordance between self-reported method and exogenous hormones did not differ by HIV status. Among African women with and at risk for HIV, testing of exogenous hormones revealed agreement with self-reported contraceptive use for most women. However, unexpected exogenous hormones were identified among self-reported hormonal contraceptive users and nonusers, and an important fraction of women reporting hormonal contraceptive use had no hormones detected; absence of oral contraceptive hormones could be due, at least in part, to samples taken during the hormone-free interval. Misreporting of hormonal contraceptive use could lead to biased results in observational studies of the relationship between contraceptive use and health

Do saw palmetto extracts block human alpha1-adrenoceptor subtypes in vivo?

Science.gov (United States)

Goepel, M; Dinh, L; Mitchell, A; Schäfers, R F; Rübben, H; Michel, M C

2001-02-15

To test whether saw palmetto extracts, which act as alpha1-adrenoceptor antagonists in vitro, also do so in vivo in man. In a placebo-controlled, double-blind, four-way cross-over study 12 healthy young men were treated with three different saw palmetto extract preparations (320 mg o.d.) for 8 days each. On the last day, before and 2, 4 and 6 hr after drug intake blood pressure and heart rate were determined and blood samples obtained, which were used in an ex vivo radioreceptor assay with cloned human alpha1-adrenoceptor subtypes. Saw palmetto extract treatment did not result in alpha1-adrenoceptor subtype occupancy in the radioreceptor assay. Although the saw palmetto extracts caused minor reductions of supine blood pressure, they did not affect blood pressure during orthostatic stress testing and did not alter heart rate under either condition. Moreover, plasma catecholamines remained largely unaltered. Despite their alpha1-adrenoceptor antagonist effects in vitro, therapeutically used doses of saw palmetto extracts do not cause alpha1-adrenoceptor antagonism in man in vivo. Copyright 2001 Wiley-Liss, Inc.

Purification of human platelet-derived growth factor

International Nuclear Information System (INIS)

Raines, E.W.; Ross, R.

1985-01-01

The paper describes a method for purification of human platelet-derived growth factor (PDGF) from outdated platelet-rich plasma (PRP) using commonly available laboratory reagents and yielding a mitogen purified 800,000-fold over the starting material. [ 3 H]thymidine incorporation into DNA of cultured cells responsive to PDGF represents the most readily available method to follow its purification and define the biological activity of a purified preparation. Other assays to quantitate PDGF include radioreceptor assay and radioimmunoassay

Thyroid hormone radioimmunoassay

International Nuclear Information System (INIS)

Rodriguez, S.; Richmond, M.; Quesada, S.; Lahaman, S.; Ramirez, A.; Herrera, J.F.

1988-01-01

The International Atomic Energy Agency (AIEA) is carrying out the ARCAL VIII Program 'Thiroid Hormone Readioimmunoassay'. The Immunoassay Laboratory of INCIENSA is in charge of this program, with the participation of four National Hospital System laboratories, which carried out Thyroxine (T4). Triodothyroxine (T3) and Thyroid Stimulating Hormone (TSH) assays with NETRIA Reagents (North East Thames Region Immunoassay Unit). The variability was shown to be between 9-20 per cent for T4, 12-22 per cent for TSH and 22-36 per cent for T3. The study also evaluated the quality of a tracer (T3-l125 and T4 l125) produced at INCIENSA. In this case the intrassay variability was 8,4 per cent for T3 and 6,8 per cent for T4 in 32 determinations evaluated during 6 months. It was concluded that the T4 and TSH tests but not the T3 test are valid and reproducible when NETRIA Ragents are used. The tracer made at INCIENSA can be used up to 6 weeks after the radioiodination with l125. A successful thyroid-related hormones quality control was defined in Costa Rica by taking advantage of the support of a prestigious international agency, the IAEA. (author). 13 refs, 4 figs

External quality-control surveys of peptide hormone radioimmunoassays in the Federal Republic of Germany. The present status

International Nuclear Information System (INIS)

Breuer, H.; Jungbluth, D.; Roehle, G.; Marschner, I.; Scriba, P.C.; Wood, W.G.

1978-01-01

Two types of quality-control survey (QCS) of hormone assays are performed in the Federal Republic of Germany. In the one survey, the participating laboratories are requested to determine seven or eight different hormones in two lyophilized sera that are distributed several times a year. Because of the lack of reference methods for peptide hormones, the statistical evaluation of the results indicates only whether they are ''correct'' or subject to systematic or nonsystematic errors with respect to the findings of the other participants. In the other survey, the participating laboratories are requested to assay only one given hormone in some 20 deep-frozen sera (including standards in hormone-free sera for derivation of a standard curve) that are distributed at relatively long intervals. The statistical analysis of the data derived from these QCSs allows - together with the methodological inquiry form - detection of probable causes for discrepancies in the results. (author)

Preparation of directly iodinated steroid hormones and related directly halogenated compounds

International Nuclear Information System (INIS)

Sahadevan, V.

1981-01-01

The preparation of directly iodinated radioactive steroid hormones is described for use in radioimmunoassays or radiolocalization and treatment of human breast tumours. The radioactive iodinated steroid hormone is prepared by reacting a parent steroid hormone with an alkali metal iodide containing radioactive 123 I, 125 I, 130 I or 131 I in the presence of hydrogen peroxide or chloramine-T. The parent steroid hormones include the adrenal corticosteroids, the estrogens, the progestogens, the progestins and the diuretic and antidiuretic agents. The radioactive iodinated steroid hormone is prepared by iodinating the parent steroid hormone directly on the cyclopentanophenanthrene nucleus. The radioactive iodinated steroid hormones have the same antigenicity and receptor site specificity as the parent steroid hormone. The invention is illustrated by 1) the method of iodination of estradiol-17β, 2) results for the percentage labelling of several steroids and steroid hormones, 3) results for the radioimmunoassay of 125 I-estradiol and 4) results for the binding of directly iodinated estradiol-17β in an estrogen receptor assay of human breast cancer. (U.K.)

Sleep Deprivation Alters Rat Ventral Prostate Morphology, Leading to Glandular Atrophy: A Microscopic Study Contrasted with the Hormonal Assays

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Daniel P. Venâncio

2012-01-01

Full Text Available We investigated the effect of 96 h paradoxical sleep deprivation (PSD and 21-day sleep restriction (SR on prostate morphology using stereological assays in male rats. After euthanasia, the rat ventral prostate was removed, weighed, and prepared for conventional light microscopy. Microscopic analysis of the prostate reveals that morphology of this gland was altered after 96 h of PSD and 21 days of SR, with the most important alterations occurring in the epithelium and stroma in the course of both procedures compared with the control group. Both 96 h PSD and 21-day SR rats showed lower serum testosterone and higher corticosterone levels than control rats. The significance of our result referring to the sleep deprivation was responsible for deep morphological alterations in ventral prostate tissue, like to castration microscopic modifications. This result is due to the marked alterations in hormonal status caused by PSD and SR.

Sleep Deprivation Alters Rat Ventral Prostate Morphology, Leading to Glandular Atrophy: A Microscopic Study Contrasted with the Hormonal Assays

Science.gov (United States)

Venâncio, Daniel P.; Andersen, Monica L.; Vilamaior, Patricia S. L.; Santos, Fernanda C.; Zager, Adriano; Tufik, Sérgio; Taboga, Sebastião R.; De Mello, Marco T.

2012-01-01

We investigated the effect of 96 h paradoxical sleep deprivation (PSD) and 21-day sleep restriction (SR) on prostate morphology using stereological assays in male rats. After euthanasia, the rat ventral prostate was removed, weighed, and prepared for conventional light microscopy. Microscopic analysis of the prostate reveals that morphology of this gland was altered after 96 h of PSD and 21 days of SR, with the most important alterations occurring in the epithelium and stroma in the course of both procedures compared with the control group. Both 96 h PSD and 21-day SR rats showed lower serum testosterone and higher corticosterone levels than control rats. The significance of our result referring to the sleep deprivation was responsible for deep morphological alterations in ventral prostate tissue, like to castration microscopic modifications. This result is due to the marked alterations in hormonal status caused by PSD and SR. PMID:22927719

Assessment of the hormonal state of medical personnel occupationally exposed to ionizing radiation

International Nuclear Information System (INIS)

Bliznakov, V.; Maleeva, A.; Mikhaylov, M.

1982-01-01

Testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations are assayed in 14 men against the background of occupational exposure of medical personnel to small - dose radiations. Low testosterone values, and elevated LH and FSH levels are established. A preliminary conclusion is made according to which in occupationally exposed men in the field of medicine there is a disturbance of hormonal secretion along the hypophysis - target gland axis. Twenty normal men of comparable age are studied for control purpose. (author)

{sup 177}Lutetium-DOTATATE peptide radio-receptor therapy for patients with endocrine neoplasm and the individualized semi-automatic dosimetry. A retrospective analysis; {sup 177}Lutetium-DOTATATE-Peptid-Radio-Rezeptor-Therapie bei Patienten mit neuroendokrinen Neoplasien und die individualisierte, semi-automatische-Dosimetrie. Eine retrospektive Analyse

Energy Technology Data Exchange (ETDEWEB)

Loeser, Anastassia

2016-09-28

The {sup 177}lutetium-DOTATATE peptide radio-receptor therapy is a promising approach for the palliative treatment of patients with inoperable endocrine neoplasm. The individually variable biological dispersion and the tumor uptake including the protection of critical organs require a precise and reliable organ and tumor dosimetry. The HERMES Hybrid dosimetry module has appeared as reliable and user-friendly tool for clinical application. The next step is supposed to by the complete integration of 3D SPECT imaging.

Local Production of Luteinizing Hormone Antisera to Be Used In Radioimmunoassay Technique

International Nuclear Information System (INIS)

Mahmoud, S. M.; Ali, N. I.; Abdullah, O. M.; Albaqi, W. A. A.

2004-01-01

Luteinizing hormone (LH) is a glycoprotein hormone. It is one of the coordinate pituitary regulators of gonadal function (2). Serum LH concentration increase in polycystic ovary syndrome (PCOS) which is the most common cause of infertility among infertile women. (3). The expensive imported LH kits lead us to think seriously to develop our local reagents. The antibody is a backbone of RIA reagents and this study is describing how to raise LH antibody and how to use it for a local LH kit production. Human LH was emulsified to Freunds adjuvant and acted as an immunogen Local Sudanese sheep was used to raise anti-LH antisera. The obtained antisera were adsorbed physically onto polystyrene beads with a dilution of 1/100.000 in order to develop an RIA kit. Optimization of LH assay conditions including incubation temperature and reaction time were performed. Assay validation tests including specificity, sensitivity, linearity, recovery, reproducibility and comparability for the local kit were performed. The polystyrene beads RIA LH system showed a minimum detectable dose of 0.04 m U/L. For the linearity and recovery tests, the regression coefficients were found to be 0.99, 0.997 respectively. The assay was found to be reproducible where the coefficients of variation within and between assays were less than 10%. Comparison between local and Chinese reagents for Luteinizing hormone determination in serum showed high correlation where r=0.96. (Authors)

Local production of luteinizing hormone antisera to be used in radioimmunoassay technique

International Nuclear Information System (INIS)

Mahmoud, S. M.; Ali, N. I.; Abdullah, O. M.; Almahi, W. A. A.

2004-12-01

Luteinizing hormone (LH) is a glycoprotein hormone. It is one of the coordinate pituitary regulators of gonadal function (2). Serum LH concentration increase in polycystic ovary syndrome (PCOS) which is the most common cause of infertility among infertile women (3). The expensive imported LH kits lead us to think seriously to develop our local reagents. The antibody is a backbone of RIA reagents and this study is describing how to raise LH antibody and how to use it for a local LH kit production. Human LH was emulsified to Freunds adjuvant and acted as an immunogen local Sudanese sheep was used to raise anti-LH antisera. The obtained antisera were adsorbed physically onto polystyrene beads with a dilution of 1/100.000 in order to develop an RIA kit. Optimization of LH assay conditions including incubation temperature and reaction time were performed. Assay validation tests including specificity, sensitivity, linearity, recovery, reproducibility and comparability for the local kit were performed. The polystyrene beads RIA LH system showed a minimum detectable dose of 0.04 m U/L. For the linearity and recovery tests, the regression coefficients were found to be 0.99, 0.997 respectively. The assay was found to be reproducible where the coefficients of variation within and between assays were less than 10%. Comparison between local and Chinese reagents for luteinizing hormone determination in serum showed high correlation where r=0.96. (Author)

Enzyme-immuno assay for total estrogens and human placental lactogen. Comparison with radio-immuno-assay in normal pregnancy-monitoring

International Nuclear Information System (INIS)

Raichvarg, D.; Tallet, F.; Lajeunie, E.; Bonnaire, Y.; Danglas, P.

1980-01-01

The concentrations of estrogens (E) and human placental lactogen (HLP) are estimated in sera by radio immuno-assay (RIA) and enzyme-immuno-assay (EIA). Statistical data indicate mean intra-assay variation coefficients of 7% and 12% for E and HLP tests, respectively. The correlation coefficient (RIA/EIA) are found higher than 0,9% for both hormonal assays. The dilution curves obtained by RIA and EIA are similar. However, Student'test gives a significant difference for E determination. In fact, total E and E 3 only are measured by EIA and RIA, respectively. In most cases biological interferences are negligible except for HLP in presence of higher protein or haemoglobin levels. RIA and EIA are performed to study serum HLP and E levels throughout normal pregnancies. Results allow to use EIA for HLP and E evaluations in pregnancy-monitoring [fr

New Solid Phases for Estimation of Hormones by Radioimmunoassay Technique

International Nuclear Information System (INIS)

Sheha, R.R.; Ayoub, H.S.M.; Shafik, M.

2013-01-01

The efforts in this study were initiated to develop and validate new solid phases for estimation of hormones by radioimmunoassay (RIA). The study argued the successful application of different hydroxy apatites (HAP) as new solid phases for estimation of Alpha fetoprotein (AFP), Thyroid Stimulating hormone (TSH) and Luteinizing hormone (LH) in human serum. Hydroxy apatites have different alkali earth elements were successfully prepared by a well-controlled co-precipitation method with stoichiometric ratio value 1.67. The synthesized barium and calcium hydroxy apatites were characterized using XRD and Ftir and data clarified the preparation of pure structures of both BaHAP and CaHAP with no evidence on presence of other additional phases. The prepared solid phases were applied in various radioimmunoassay systems for separation of bound and free antigens of AFP, TSH and LH hormones. The preparation of radiolabeled tracer for these antigens was carried out using chloramine-T as oxidizing agent. The influence of different parameters on the activation and coupling of the used apatite particles with the polyclonal antibodies was systematically investigated and the optimum conditions were determined. The assay was reproducible, specific and sensitive enough for regular estimation of the studied hormones. The intra-and inter-assay variation were satisfactory and also the recovery and dilution tests indicated an accurate calibration. The reliability of these apatite particles had been validated by comparing the results that obtained by using commercial kits. The results finally authenticates that hydroxyapatite particles would have a great potential to address the emerging challenge of accurate quantitation in laboratory medical application

Radioimmunoassay for thyroid stimulating hormone (TSH)

International Nuclear Information System (INIS)

1980-01-01

An improved double antibody radioimmunoassay method is described for the determination of thyroid stimulating hormone (TSH) in biological and other fluids. Highly purified second antibody is immobilised on to hydrophilic, hydrolyzed polyacrylamide particles of a suspendable size to form a solid phase second antibody reagent. The immobilised second antibody reagent is used to precipitate the reaction product of the first antibody with labelled and unlabelled thyroid stimulating hormone (TSH-anti-TSH-complex) so as to produce a two-phase system which permits rapid and efficient separation of bound TSH in the solid phase from free TSH in the liquid phase. Details of the preparation of this novel second antibody-polyacrylamide reagent and of the assay procedure for human TSH are described. (U.K.)

The current state of external quality control surveys in the German Federal Republic in the field of peptide hormone radioimmunoassays

International Nuclear Information System (INIS)

Marschner, I.; Scriba, P.C.; Wood, W.G.; Breuer, H.; Jungbluth, D.; Roehle, G.

1977-01-01

Two types of quality control surveys (QSC) are performed in the Federal Republic of Germany in the field of hormone assays: 1) The distribution of two lyophilized sera at regular intervals, in which the participants have to determine 7 or 8 different hormones. Because of the lack of reference methods for peptide hormones, the statistical evaluation of the results indicates only whether the results of the participants are 'correct' or contain systematic or nonsystematic errors with respect to the findings of the other participants. 2) The distribution of approximately 20 deep-frozen sera (including a standard curve in hormone-free serum) in which the participant has to assay a single hormone. These 20 sera-QCS are performed only at long intervals for a given hormone. The statistical analysis of the rate of the radioactive counts of the QCS-sera and those of the participants' standard curves allows - together with a methodological inquiry form - detection of probable causes for deviating results. (orig.) [de

Serum sample containing endogenous antibodies interfering with multiple hormone immunoassays. Laboratory strategies to detect interference

Directory of Open Access Journals (Sweden)

Elena García-González

2016-04-01

Full Text Available Objectives: Endogenous antibodies (EA may interfere with immunoassays, causing erroneous results for hormone analyses. As (in most cases this interference arises from the assay format and most immunoassays, even from different manufacturers, are constructed in a similar way, it is possible for a single type of EA to interfere with different immunoassays. Here we describe the case of a patient whose serum sample contains EA that interfere several hormones tests. We also discuss the strategies deployed to detect interference. Subjects and methods: Over a period of four years, a 30-year-old man was subjected to a plethora of laboratory and imaging diagnostic procedures as a consequence of elevated hormone results, mainly of pituitary origin, which did not correlate with the overall clinical picture. Results: Once analytical interference was suspected, the best laboratory approaches to investigate it were sample reanalysis on an alternative platform and sample incubation with antibody blocking tubes. Construction of an in-house ‘nonsense’ sandwich assay was also a valuable strategy to confirm interference. In contrast, serial sample dilutions were of no value in our case, while polyethylene glycol (PEG precipitation gave inconclusive results, probably due to the use of inappropriate PEG concentrations for several of the tests assayed. Conclusions: Clinicians and laboratorians must be aware of the drawbacks of immunometric assays, and alert to the possibility of EA interference when results do not fit the clinical pattern. Keywords: Endogenous antibodies, Immunoassay, Interference, Pituitary hormones, Case report

Quality control of estrogen receptor assays.

Science.gov (United States)

Godolphin, W; Jacobson, B

1980-01-01

Four types of material have been used for the quality control of routine assays of estrogen receptors in human breast tumors. Pieces of hormone-dependent Nb rat mammary tumors gave a precision about 40%. Rat uteri and rat tumors pulverized at liquid nitrogen temperature and stored as powder yielded precision about 30%. Powdered and lyophilised human tumors appear the best with precision as good as 17%.

There Is No Elevation of Immunoglobulin E Levels in Albanian Patients with Autoimmune Thyroid Diseases

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Hatixhe Latifi-Pupovci

2014-01-01

Full Text Available Background. Studies in several ethnic groups reported high incidence of elevated levels of immunoglobulin E (IgE in patients with autoimmune thyroid diseases (ATD, especially in patients with Graves’ disease. Objective. To study association between serum levels of IgE and thyroid stimulating hormone receptor antibodies (TRAb in Albanian patients with ATD. Material and Methods. Study was performed in 40 patients with Graves’ disease, 15 patients with Hashimoto’s thyroiditis, and 14 subjects in the control group. The IgE levels were measured by immunoradiometric assay, whereas the TRAb levels were measured by radioreceptor assay. Results. In all groups of subjects the IgE levels were within reference values (<200 kIU/L. Significant difference in mean concentration of IgE was found between two groups of Graves’ disease patients, and those with normal and elevated TRAb levels (22.57 versus 45.03, P<0.05. Positive correlation was found between TRAb and IgE only in Graves’ disease patients (r=0.43, P=0.006. Conclusion. In Albanian patients with ATD there is no elevation of IgE levels. This could be the result of low prevalence of allergic diseases in Albanian population determined by genetic and environmental factors.

Radioimmunoassays of parathyroid hormone: Clinical value of the midregion and c-terminal assay

International Nuclear Information System (INIS)

Hengst, K.; Raidt, H.; Hoegemann, B.; Wagner, H.

1984-01-01

PTH was measured by midregion and carboxy-terminal assay in 20 patients suffering from primary hyperparathyroidism, 30 patients with secondary hyperparathyroidism, 10 persons with tertiary hyperparathyroidism, 50 patients who underwent transplantation of the kidney, 10 patients with hypoparathyroidism and 10 patients with other hypocalcemia as well as in 50 normal persons. Diagnosing hyperparathyroidism both assays were successful, when serum kreatinine was within the normal range. Especially midregion fragments became elevated, when serum kreatinine was above 2,0 mg. During renal failure diagnosis of hyperparathyroidism and hypoparathyroidism is more difficult. In normal renal function, however, the midregion assay is more sensitive for diagnosis of hypoparathyroidism compared to the carboxy-terminal assay. After kidney transplantation midregion levels of PTH are elevated, perhaps because of a failure of the transplanted kidney to eliminate the midregion fragment. (orig.) [de

Evaluation of the 2. generation radio-receptional assay for anti-TSH receptor antibodies (TRAb) in autoimmune thyroid diseases. Comparison with 1. generation and anti-thyroperoxidae antibodies (AbTPO)

International Nuclear Information System (INIS)

Giovanella, L.; Ceriani, L.; Garacini, S.

2001-01-01

The detection of autoantibodies to the TSH-receptor (TRAb) by radio-receptor assays (RRA) is widely requested in clinical practice for the diagnostic work-up of Graves' disease and its differentiation from diffuse thyroid autonomy. Additionally, TRAb measurement can be useful during antithyroid drug treatment of Graves' disease to evaluate the risk of relapse after therapy discontinuation. Nevertheless, some patients affected by Graves' disease are TRAb-negative when 1. generation assay is used. In this study the diagnostic performance of a newly developed 2. generation TRAb assay (TRAK human DYNOtest(R), BRAHMS Diagnostica GmbH, Berlin, Germany) was evaluated in 74 untreated patients affected by Graves' disease, in 53 untreated patients affected by Hashimoto's thyroiditis and in 88 patients affected by euthyroid nodular goiter. It was also compared the new TRAb assay with the 1. generation test (TRAK(R) Assay, BRAHMS Diagnostica GmbH, Berlin, Germany) and anti-thyroperoxidase assay (AbTPO DYNOtest(R), BRAHMS GmbH, Berlin). The 2. generation TRAb assay showed the better diagnostic sensitivity in Graves' disease (97%) with respect to the 1. generation assay (85%) and AbTPO assay (64%). The AbTPO assay was positive in 50 of 53 (94%) patients affected by autoimmune thyroiditis. The 1. and 2. generation TRAb assays were positive in 4 (7%) and 7 (13%) of 53 patients affected by autoimmune thyroiditis, respectively. No patients affected by nodular goiter showed positive 1. and 2. generation TRAb assay while AbTPO levels were positive in 8 of 88 patients (specificity 91%). In conclusion, the 2. generation TRAb assay is clearly more sensitive than the 1. generation test and should be used in clinical practice to minimize the incidence of TRAb-negative Graves' disease. Long term prospective studies are needed to evaluate the prognostic role of 2. generation TRAb assay in Graves' disease. The assay of AbTPO is the best marker for autoimmune thyroiditis but is clearly less

Evaluation of the 2. generation radio-receptional assay for anti-TSH receptor antibodies (TRAb) in autoimmune thyroid diseases. Comparison with 1. generation and anti-thyroperoxidae antibodies (AbTPO)

Energy Technology Data Exchange (ETDEWEB)

Giovanella, L.; Ceriani, L.; Garacini, S. [University Hospital Ospedale di Circolo e Fondazione Macchi, Dept. of Nuclear Medicine, Lab. of Endocrinology and Thyroid Unit, Varese (Italy)

2001-03-01

The detection of autoantibodies to the TSH-receptor (TRAb) by radio-receptor assays (RRA) is widely requested in clinical practice for the diagnostic work-up of Graves' disease and its differentiation from diffuse thyroid autonomy. Additionally, TRAb measurement can be useful during antithyroid drug treatment of Graves' disease to evaluate the risk of relapse after therapy discontinuation. Nevertheless, some patients affected by Graves' disease are TRAb-negative when 1. generation assay is used. In this study the diagnostic performance of a newly developed 2. generation TRAb assay (TRAK human DYNOtest(R), BRAHMS Diagnostica GmbH, Berlin, Germany) was evaluated in 74 untreated patients affected by Graves' disease, in 53 untreated patients affected by Hashimoto's thyroiditis and in 88 patients affected by euthyroid nodular goiter. It was also compared the new TRAb assay with the 1. generation test (TRAK(R) Assay, BRAHMS Diagnostica GmbH, Berlin, Germany) and anti-thyroperoxidase assay (AbTPO DYNOtest(R), BRAHMS GmbH, Berlin). The 2. generation TRAb assay showed the better diagnostic sensitivity in Graves' disease (97%) with respect to the 1. generation assay (85%) and AbTPO assay (64%). The AbTPO assay was positive in 50 of 53 (94%) patients affected by autoimmune thyroiditis. The 1. and 2. generation TRAb assays were positive in 4 (7%) and 7 (13%) of 53 patients affected by autoimmune thyroiditis, respectively. No patients affected by nodular goiter showed positive 1. and 2. generation TRAb assay while AbTPO levels were positive in 8 of 88 patients (specificity 91%). In conclusion, the 2. generation TRAb assay is clearly more sensitive than the 1. generation test and should be used in clinical practice to minimize the incidence of TRAb-negative Graves' disease. Long term prospective studies are needed to evaluate the prognostic role of 2. generation TRAb assay in Graves' disease. The assay of AbTPO is the best marker for

Simultaneous measurement of hormone release and secretagogue binding by individual pituitary cells

International Nuclear Information System (INIS)

Smith, P.F.; Neill, J.D.

1987-01-01

The quantitative relationship between receptor binding and hormone secretion at the single-cell level was investigated in the present study by combining a reverse hemolytic plaque assay for measurement of luteinizing hormone (LH) secretion from individual pituitary cells with an autoradiographic assay of 125 I-labeled gonadontropin-releasing hormone (GnRH) agonist binding to the same cells. In the plaque assay, LH secretion induces complement-mediated lysis of the LH-antibody-coated erythrocytes around the gonadotropes, resulting in areas of lysis (plaques). LH release from individual gonadotropes was quantified by comparing radioimmunoassayable LH release to hemolytic area in similarly treated cohort groups of cells; plaque area was linearly related to the amount of LH secreted. Receptor autoradiography was performed using 125 I-labeled GnRH-A (a superagonist analog of GnRH) both as the ligand and as the stimulant for LH release in the plaque assay. The grains appeared to represent specific and high-affinity receptors for GnRH because (i) no pituitary cells other than gonadotropes bound the labeled ligand and (ii) grain development was progressively inhibited by coincubation with increasing doses of unlabeled GnRH-A. The authors conclude that GnRH receptor number for any individual gonadotrope is a weak determinant of the amount of LH it can secrete; nevertheless, full occupancy of all its GnRH receptors is required for any gonadotrope to reach its full LH-secretory capacity. Apparently the levels of other factors comprising the steps along the secretory pathway determine the secretory capacity of an individual cell

Parathyroid hormone: radioimmunoassay and clinical interpretation

International Nuclear Information System (INIS)

Hawker, C.D.

1975-01-01

A radioimmunoassay for serum immunoreactive parathyroid hormone (iPTH), which has had widespread clinical use for five years, is described in detail. The iPTH results in large groups of patients are reported, and are discussed in relation to the specificity of the assay and in relation to other assays. The assay has excellent precision and is highly proficient in discrimination of groups of patients. Ninety-three percent of 412 patients with surgically proven primary hyperparathyroidism were confidently separated from normal subjects or patients with hypercalcemia owing to other causes, while 86 percent of 160 patients with chronic renal failure and secondary hyperparathyroidism had iPTH values more than 2 S.D. above the normal mean. Results in patients with ectopic hyperparathyroidism were lower than in primary hyperparathyroidism although these groups showed considerable overlap. The antiserum used in this assay for iPTH appears to be specific for the carboxy-terminal region of the secreted or intact form of PTH but recognizes predominantly the secreted form rather than carboxy-terminal fragments believed to be in the circulation. It does not recognize amino terminal fragments. The assay is useful in selective venous catheterization for preoperative localization of hyperfunctioning parathyroid tissue

Radioimmunoassay and the hormones of thyroid function

International Nuclear Information System (INIS)

Stahl, R.J.

1975-01-01

Radioimmunoassay (RIA) has provided the tools for wide-reaching investigations that have changed and continue to change many important concepts of thyroid physiology and pathophysiology. The RIA for human thyrotropin (TSH) was developed in 1965; development of the RIA for triiodothyronine (T 3 ), thyroxine(T 4 ), thyroxine-binding globulin (TBG), and recently, thyrotropin-releasing hormone (TRH) and thyroglobulin (Tg) followed. The capacity to measure nanogram and picogram concentrations with relative ease and speed has permitted the demonstration of dynamic relationships of the intrathyroidal and circulating thyroid hormones to each other and to the pituitary and hypothalamic regulating hormones. Evidence for the presence of cross-influences between TRH and other hypothalamic regulating hormones on the secretion of pituitary hormones has accumulated. The impact of the new information on clinical practice is now becoming evident. There is new appreciation of the value of assaying serum T 3 and TSH concentrations in the clinical management of patients with disturbed function of the thyroid, pituitary, or hypothalamus. The necessary components for RIA performance can be purchased separately or in kit form from commercial sources. With appropriate quality-control procedures, precise, sensitive, and reliable data can be generated. Awareness of the specific technical problems relating to the RIA of these hormones is absolutely necessary to assure reliable results. The availability of kits or their components permits the performance of these studies in the community hospital and in reliable commercial-service laboratories. (U.S.)

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

Anti-Müllerian Hormone and Its Clinical Use in Pediatrics with Special Emphasis on Disorders of Sex Development

DEFF Research Database (Denmark)

Lindhardt Johansen, Marie; Hagen, Casper P; Johannsen, Trine Holm

2013-01-01

Using measurements of circulating anti-Müllerian hormone (AMH) in diagnosing and managing reproductive disorders in pediatric patients requires thorough knowledge on normative values according to age and gender. We provide age- and sex-specific reference ranges for the Immunotech assay and conver......Using measurements of circulating anti-Müllerian hormone (AMH) in diagnosing and managing reproductive disorders in pediatric patients requires thorough knowledge on normative values according to age and gender. We provide age- and sex-specific reference ranges for the Immunotech assay...

Development of homologous radioimmunoassays for equine growth hormone and equine prolactin and their application to the detection of circulating levels of hormone in horse plasma

Energy Technology Data Exchange (ETDEWEB)

Cahill, C.M.; Hayden, T.J. [University Coll., Dublin (Ireland); Ven der Kolk, H. [Rijksuniversiteit Utrecht (Netherlands); Goode, J.A. [Agricultural Research Council, Cambridge (United Kingdom). Inst. of Animal Physiology

1994-12-31

Highly purified and well-characterized preparations of equine prolactin and growth hormone from equine pituitary glands were employed to set up highly sensitive and specific homologous radioimmunoassays (RIA) for the measurement of hormone in horse plasma. The limit of sensitivity of the GH RIA was 1.2 ng/ml with mean intra -and inter- assay coefficients of variation (CV) of 6.6 and 10%, respectively. The sensitivity of the equine prolactin (ePRL) RIA was 0.5 ng/ml with mean intra and inter-assay CV of 9.1 and 15.6%, respectively. Dose-response curves of a crude pituitary gland extract and plasma samples collected from a mare and foal were parallel to the standards and the PRL RIA was clinically validated by administration of thyrotropin-releasing hormone (TRH). Plasma samples taken at 15 min intervals over 24 h from lactating mares gave 24 h mean GH values in the range 5.5 to 7.95 ng/ml. Large intermittent elevations of GH activity were detected. The mean 24 h PRL concentrations were between 3.2-10.4 ng/ml in the lactating animals, with higher concentrations earlier in lactation. Long episodic bursts of PRL were detected. (authors). 48 refs., 9 figs.

Development of homologous radioimmunoassays for equine growth hormone and equine prolactin and their application to the detection of circulating levels of hormone in horse plasma

International Nuclear Information System (INIS)

Cahill, C.M.; Hayden, T.J.; Ven der Kolk, H.; Goode, J.A.

1994-01-01

Highly purified and well-characterized preparations of equine prolactin and growth hormone from equine pituitary glands were employed to set up highly sensitive and specific homologous radioimmunoassays (RIA) for the measurement of hormone in horse plasma. The limit of sensitivity of the GH RIA was 1.2 ng/ml with mean intra -and inter- assay coefficients of variation (CV) of 6.6 and 10%, respectively. The sensitivity of the equine prolactin (ePRL) RIA was 0.5 ng/ml with mean intra and inter-assay CV of 9.1 and 15.6%, respectively. Dose-response curves of a crude pituitary gland extract and plasma samples collected from a mare and foal were parallel to the standards and the PRL RIA was clinically validated by administration of thyrotropin-releasing hormone (TRH). Plasma samples taken at 15 min intervals over 24 h from lactating mares gave 24 h mean GH values in the range 5.5 to 7.95 ng/ml. Large intermittent elevations of GH activity were detected. The mean 24 h PRL concentrations were between 3.2-10.4 ng/ml in the lactating animals, with higher concentrations earlier in lactation. Long episodic bursts of PRL were detected. (authors). 48 refs., 9 figs

Radioimmunoassay of canine growth hormone

International Nuclear Information System (INIS)

Eigenmann, J.E.; Eigenmann, R.Y.

1981-01-01

A sensitive radioimmunoassay (RIA) for canine growth hormone (GH) was developed. Antibodies were elicited in rhesus monkeys. One antiserum exhibited a working titer at a dilution of 1:500 000. Radioiodination was performed enzymatically employing lactoperoxidase. Logit-log transformation and least squares fitting resulted in straight line fitting of the standard curve between 0.39 and 50 ng/ml. Formation of large-molecular [ 125 I]GH during storage caused diminished assay sensitivity. Therefore [ 125 I]GH was re-purified by gel chromatography. Using this procedure, high and reproducible assay sensitivity was obtained. Tracer preparations were used for as long as 3 months after iodination. Diluted plasma from normal and acromegalic dogs resulted in a dose-response curve parallel to the standard curve. Canine prolactin exhibited a cross-reactivity of 2%. The within-assay coefficient of variation (CV) was 3.8 and the between-assay CV was 7.2%. Mean plasma GH concentration in normal dogs was 1.92 +- 0.14 ng/ml (mean +- SEM.) GH levels in acromegalic dogs were appreciably higher. Insulin-induced hypoglycaemia, arginine and ornithine administration resulted in inconsistent and sluggish GH increment. A better response was obtained by injecting a low dose of clonidine. Clonidine administration to hypopituitary dogs resulted in absent or poor GH increment. (author)

Radioimmunoassay of parathyroid hormone: past and future

International Nuclear Information System (INIS)

Yalow, R.S.

1986-01-01

In this report on radioimmunoassay of parathyroid hormone (iPTH) it was shown that the rate of disappearance of iPTH from plasma differed markedly in patients with primary hyperthyroidism or those with uremia and secondary hyperparathyroidism and that for each patient the rate of disappearance depended on the antiserum used for assay. The heterogeneity of iPTH in plasma was soon rapidly confirmed in many laboratories. (Auth.)

New fluorimetric assay of horseradish peroxidase using sesamol as substrate and its application to EIA

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Hidetoshi Arakawa

2012-04-01

Full Text Available Horseradish peroxidase (HRP is generally used as a label enzyme in enzyme immunoassay (EIA. The procedure used for HRP detection in EIA is critical for sensitivity and precision. This paper describes a novel fluorimetric assay for horseradish peroxidase (HRP using sesamol as substrate. The principle of the assay is as follow: sesamol (3,4-methylenedioxy phenol is reacted enzymatically in the presence of hydrogen peroxide to produce dimeric sesamol. The dimer is fluorescent and can be detected sensitively at ex. 347 nm, em. 427 nm.The measurable range of HRP was 1.0×10−18 to 1.0×10−15 mol/assay, with a detection limit of 1.0×10−18 mol/assay. The coefficient of variation (CV, n=8 was examined at each point on the standard curve, with a mean CV percentage of 3.8%. This assay system was applied to thyroid stimulating hormone (TSH EIA using HRP as the label enzyme. Keywords: Sesamol, Fluorescence, Enzyme immunoassay (EIA, Horseradish peroxidase (HRP, Thyroid stimulating hormone (TSH

Identification of an estrogenic hormone receptor in Caenorhabditis elegans

International Nuclear Information System (INIS)

Mimoto, Ai; Fujii, Madoka; Usami, Makoto; Shimamura, Maki; Hirabayashi, Naoko; Kaneko, Takako; Sasagawa, Noboru; Ishiura, Shoichi

2007-01-01

Changes in both behavior and gene expression occur in Caenorhabditis elegans following exposure to sex hormones such as estrogen and progesterone, and to bisphenol A (BPA), an estrogenic endocrine-disrupting compound. However, only one steroid hormone receptor has been identified. Of the 284 known nuclear hormone receptors (NHRs) in C. elegans, we selected nhr-14, nhr-69, and nhr-121 for analysis as potential estrogenic hormone receptors, because they share sequence similarity with the human estrogen receptor. First, the genes were cloned and expressed in Escherichia coli, and then the affinity of each protein for estrogen was determined using a surface plasmon resonance (SPR) biosensor. All three NHRs bound estrogen in a dose-dependent fashion. To evaluate the specificity of the binding, we performed a solution competition assay using an SPR biosensor. According to our results, only NHR-14 was able to interact with estrogen. Therefore, we next examined whether nhr-14 regulates estrogen signaling in vivo. To investigate whether these interactions actually control the response of C. elegans to hormones, we investigated the expression of vitellogenin, an estrogen responsive gene, in an nhr-14 mutant. Semi-quantitative RT-PCR showed that vitellogenin expression was significantly reduced in the mutant. This suggests that NHR-14 is a C. elegans estrogenic hormone receptor and that it controls gene expression in response to estrogen

Whole blood microculture assay of human lymphocyte function.

Science.gov (United States)

Pauly, J L; Han, T

1976-11-01

A whole blood microculture assay is described for measuring lymphocyte reactivity to mitogenic and antigenic stimulants. This assay employs heparinized whole blood, serum-free culture medium, microtiter plates, and a Multiple Automated Sample Harvester (MASH). When this assay is compared to other leukocyte assays, its major advantages include (1) the utilization of fewer lymphocytes per microculture, thuus reducing the amount of blood required per test while increasing the number of test agents and replicate cultures which can be employed in any given experiment; (2) the conservation of mitogens, antigens, drugs, enzymes, hormones, lymphokines, and other test agents, some of which are either expensive of difficult to prepare in large quantities; (3) the elimination of lymphocyte isolation and purification procedures which may disrupt the relative proportion of T cells, B cells and antigen-processing cells; and (4) the application of an automated harvester which simplifies and expedites procedures required for processing cells for liquid scintillation counting.

A High-Throughput Screening Assay to Detect Thyroperoxidase Inhibitors (Teratology Society)

Science.gov (United States)

In support of the Endocrine Disruption Screening Program (EDSP21), the US EPA ToxCast program is developing assays to enable screening for chemicals that may disrupt thyroid hormone synthesis. Thyroperoxidase (TPO) is critical for TH synthesis and is a known target of thyroid-dis...

Preservation of active incretin hormones by inhibition of dipeptidyl peptidase IV suppresses meal-induced incretin secretion in dogs

DEFF Research Database (Denmark)

Deacon, C F; Wamberg, S; Bie, P

2002-01-01

protection has not been fully assessed, largely because suitable assays which distinguish between intact and degraded peptides have been unavailable. Using newly developed assays for intact GLP-1 and GIP, the effect of DPP IV inhibition on incretin hormone metabolism was examined. Conscious dogs were given...

Comparison level of thyroid and thyroid related hormones between sudanese males and females

International Nuclear Information System (INIS)

Madani, H.; Hassan, AME.; Basama, N. K.; Mohamed, W.A.S.; Eltayeb, N. H.; Elsayed, B. B.

2012-12-01

The function of the thyroid gland is under the control of pituitary gland through the thyroid stimulating hormone (TSH). It secretes the thyroid hormones tetra-iodo-thyronine (T 4 ) and Tri-iodo-thyronine (T 3 ). More secretion of thyroid hormones (hyperthyroidism) and low secretion (hypothyroidism) sometimes happen. This study was carried out to determine thyroid disorders in patients referred to radioimmunoassay (RIA) laboratory of Sudan Atomic Energy Commission (SAEC) during 2006-2010 for the thyroid function test. Disorders were detected using radioimmunoassay and Immuno radiometric assay. The total number of patients referred during these years were found to be 4700 sudanese patients, among them 4165 were females representing 88.6% compared to 535 males representing 11.4%. The total concentration of thyroid hormones thyroxine (T 4 ), tri iodine thyronine (T 3 ) and thyroid simulating stimulating hormones (TSH) were d terminated the prevalence of euthyroid was (66.5%), hypothyroidism was (11.8%) and of hyperthyroidism was (21.7%). These percentages did not vary significantly with sex. (Author)

The clinical evaluation of the radioimmunoassay of luteinizing hormone in urine

International Nuclear Information System (INIS)

Sobieszczyk, S.

1975-01-01

The studies comprised 177 persons: 39 healthy males, 20 women in the reproductive age, 35 postmenopausal women and 83 patients with different types of gonadal insufficiency (gonadal dysgenesis; premature ovarian failure, male hypogonadism, pituitary dwarfism). The luteinizing hormone was determined in acetone extracts of the urine by radioimmunnoassay using double antibody technique. The results of urinary LH assays allowed to differentiate the concentration of this hormone in healthy males from postmenopausal women. In a group of patients with primary ganadal deficiency urinary LH was elevated while there was a lack urinary LH in cases of secondary gonadal insufficiency. (author)

Characterization of a bioactive 15 kDa fragment produced by proteolytic cleavage of chicken growth hormone.

Science.gov (United States)

Arámburo, C; Carranza, M; Reyes, M; Luna, M; Martinez-Coria, H; Berúmen, L; Scanes, C G

2001-07-01

There is evidence for a cleaved form of GH in the chicken pituitary gland. A 25 kDa band of immunoreactive-(ir-)GH, as well as the 22 kDa monomeric form and some oligomeric forms were observed when purified GH or fresh pituitary extract were subjected to SDS-PAGE under nonreducing conditions. Under reducing conditions, the 25 kDa ir-GH was no longer observed, being replaced by a 15 kDa band, consistent with reduction of the disulfide bridges of the cleaved form. The type of protease involved was investigated using exogenous proteases and monomeric cGH. Cleaved forms of chicken GH were generated by thrombin or collagenase. The site of cleavage was found in position Arg133-Gly134 as revealed by sequencing the fragments produced. The NH2-terminal sequence of 40 amino acid residues in the 15 kDa form was identical to that of the rcGH and analysis of the remaining 7 kDa fragment showed an exact identity with positions 134-140 of cGH structure. The thrombin cleaved GH and the 15 kDa form showed reduced activity (0.8% and 0.5% of GH, respectively) in a radioreceptor assay employing a chicken liver membrane preparation. However, this fragment had a clear bioactivity in an angiogenic bioassay and was capable to inhibit the activity of deiodinase type III in the chicken liver.

Influence of gender on the correlation between plasma growth hormone profiles and urinary growth hormone excretion

DEFF Research Database (Denmark)

Main, K M; Jansson, C; Skakkebak, N

1997-01-01

A lot of interest has been directed towards the measurement of urinary growth hormone (GH) excretion instead of plasma GH profiles or provocation tests. We investigated the factors influencing the relationship between 24- and 3-hour plasma GH profiles and urinary GH excretion in a cohort of 113...... than spontaneous GH peaks. The difference in cross-reactivities of molecular GH forms in polyclonal assays may have an impact on the correlation between plasma and urinary GH. Thus, the diagnostic value of urinary GH measurement as compared to serum GH profiles needs to be further evaluated....

Thyroid Hormones Are Transport Substrates and Transcriptional Regulators of Organic Anion Transporting Polypeptide 2B1.

Science.gov (United States)

Meyer Zu Schwabedissen, Henriette E; Ferreira, Celio; Schaefer, Anima M; Oufir, Mouhssin; Seibert, Isabell; Hamburger, Matthias; Tirona, Rommel G

2018-07-01

Levothyroxine replacement therapy forms the cornerstone of hypothyroidism management. Variability in levothyroxine oral absorption may contribute to the well-recognized large interpatient differences in required dose. Moreover, levothyroxine-drug pharmacokinetic interactions are thought to be caused by altered oral bioavailability. Interestingly, little is known regarding the mechanisms contributing to levothyroxine absorption in the gastrointestinal tract. Here, we aimed to determine whether the intestinal drug uptake transporter organic anion transporting polypeptide 2B1 (OATP2B1) may be involved in facilitating intestinal absorption of thyroid hormones. We also explored whether thyroid hormones regulate OATP2B1 gene expression. In cultured Madin-Darby Canine Kidney II/OATP2B1 cells and in OATP2B1-transfected Caco-2 cells, thyroid hormones were found to inhibit OATP2B1-mediated uptake of estrone-3-sulfate. Competitive counter-flow experiments evaluating the influence on the cellular accumulation of estrone-3-sulfate in the steady state indicated that thyroid hormones were substrates of OATP2B1. Additional evidence that thyroid hormones were OATP2B1 substrates was provided by OATP2B1-dependent stimulation of thyroid hormone receptor activation in cell-based reporter assays. Bidirectional transport studies in intestinal Caco-2 cells showed net absorptive flux of thyroid hormones, which was attenuated by the presence of the OATP2B1 inhibitor, atorvastatin. In intestinal Caco-2 and LS180 cells, but not in liver Huh-7 or HepG2 cells, OATP2B1 expression was induced by treatment with thyroid hormones. Reporter gene assays revealed thyroid hormone receptor α -mediated transactivation of the SLCO2B1 1b and the SLCO2B1 1e promoters. We conclude that thyroid hormones are substrates and transcriptional regulators of OATP2B1. These insights provide a potential mechanistic basis for oral levothyroxine dose variability and drug interactions. Copyright © 2018 by The American

Effect of adrenal hormones on thyroid secretion and thyroid hormones on adrenal secretion in the sheep.

Science.gov (United States)

Falconer, I R; Jacks, F

1975-01-01

1. Previous work has shown that after stressful stimuli, sheep initially secrete increased amounts of thyroid hormone, at a time when adrenal secretion is also elevated. 2. This study was designed to evaluate (a) any short-term activation or inhibition of thyroid secretion by exogenous cortisol or ACTH administered in quantities comparable to those secreted after stress in sheep and (b) any short-term effect that exogenous thyroxine or triiodothyronine may have on the concentration of plasma cortisol in the sheep. 3. Thyroid activity was measured by determination of plasma protein bound 125I (PB125I) and total 125I in thyroid vein and mixed venous (jugular) blood. Plasma cortisol and thyroxine concentrations were measured by a competitive protein-binding assay at intervals for up to 5 hr after commencement of the experiment. 4. No evidence of an activation of thyroid secretion was found during cortisol or ACTH infusion, as monitored by thyroid vein PB125I. Similarly there was no evidence of any inhibition of thyroid function, as measured by continued secretion of thyroid hormones into thyroid vein blood. 5. No effect on plasma cortisol concentration due to thyroid hormone treatment was observed. 6. It was concluded that (a) elevated circulating corticosteroids in physiological concentrations have no short-term effects on thyroid activity in the sheep and (b) the short-term alterations in thyroid and adrenal cortical secretion observed during stress in the sheep could not be attributed to direct interaction of elevated thyroid hormone concentrations with adrenal cortical secretion. PMID:170400

Recombinant-derived chicken growth hormone used for radioimmunoassay

International Nuclear Information System (INIS)

Proudman, J.A.

1984-01-01

The use of recombinant-derived chicken growth hormone (rcGH) in an avian growth hormone (GH) radioimmunoassay (RIA) procedure is described. Antiserum to turkey GH bound 125 I-labeled rcGH, and unlabeled rcGH or turkey GH displaced binding in a dose-related manner. The dose-response curves of sera and pituitary extract from chickens and turkeys were parallel to the rcGH standard curve. Sera from hypophysectomized (hypox) chickens and turkeys produced no dose-response and did not inhibit binding of labeled rcGH. Recovery of rcGH added to hypox sera was quantitative. Modification of the homologous turkey GH RIA protocol of Proudman and Wentworth (1) to use rcGH made possible either an increase in assay sensitivity or a 3-day reduction in incubation time

Radioanalytical methods for the measurement of melanin concentrating hormone (MCH) and detection its receptor in rat tissues

International Nuclear Information System (INIS)

Lelesz, B.; Szilvassy, Z.; Varga, A.; Juhasz, B.; Nemeth, J.; Toth, G.K.; Toth, A.; Enyedi, A.; Felszeghy, E.

2016-01-01

In the present paper the development and application of a novel melanin concentrating hormone radioimmunoassay and receptor-binding assay are described. 125 I-labeling of melanin concentrating hormone (MCH) was performed by iodogen and the mono-iodinated peptide was separated by reversed-phase high performance liquid chromatography. Detection limit of the MCH specific assay was 0.2 fmol/ml. As a practical application of the novel radioimmunoassay, we measured the MCH concentration in different rat organs. High MCH concentrations were detected in the small intestine, pancreas, kidney, liver, trachea, hypothalamus and spinal cord. 125 I-MCH was also suitable for RBA to demonstrate the presence of MCH receptors in the rat brain. (author)

Effects of Hormone Deprivation, 2-Methoxyestradiol Combination Therapy on Hormone-Dependent Prostate Cancer In Vivo

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Fuminori Sato

2005-09-01

Full Text Available 2-Methoxyestradiol (2-ME has potent anti proliferative effects on cancer cells. Its utility alone or in combination with other therapies for treating prostate cancer, however, has not been fully explored. Androgendependent, independent human prostate cancer cells were examined in vivo for their response to combination therapy. Efficacy was assessed by terminal deoxynucleotide transferase-mediated dUTP nick-end labeling assay, measuring microvessel density (MVD in excised tumors. Animals harboring hormonedependent tumors treated with 2-ME alone, androgen deprivation therapy alone, or the combination of the two had a 3.1-fold, 5.3-fold, 10.1-fold increase in apoptosis, respectively. For hormone-independent tumors, treatment with 2-ME resulted in a 2.43-fold increase in apoptosis, a 73% decrease in MVD. 2-ME was most effective against hormone-dependent tumors in vivo, combination therapy resulted in a significant increase in efficacy compared to no treatment controls, trended toward greater efficacy than either 2-ME or androgen deprivation alone. Combination therapy should be investigated further as an additional therapeutic option for early prostate cancer.

Intraindividual variation in levels of serum testosterone and other reproductive and adrenal hormones in men.

Science.gov (United States)

Brambilla, Donald J; O'Donnell, Amy B; Matsumoto, Alvin M; McKinlay, John B

2007-12-01

Estimates of intraindividual variation in hormone levels provide the basis for interpreting hormone measurements clinically and for developing eligibility criteria for trials of hormone replacement therapy. However, reliable systematic estimates of such variation are lacking. To estimate intraindividual variation of serum total, free and bioavailable testosterone (T), dihydrotestosterone (DHT), SHBG, LH, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEAS), oestrone, oestradiol and cortisol, and the contributions of biological and assay variation to the total. Paired blood samples were obtained 1-3 days apart at entry and again 3 months and 6 months later (maximum six samples per subject). Each sample consisted of a pool of equal aliquots of two blood draws 20 min apart. Men aged 30-79 years were randomly selected from the respondents to the Boston Area Community Health Survey, a study of the health of the general population of Boston, MA, USA. Analysis was based on 132 men, including 121 who completed all six visits, 8 who completed the first two visits and 3 who completed the first four visits. Day-to-day and 3-month (long-term) intraindividual standard deviations, after transforming measurements to logarithms to eliminate the contribution of hormone level to intraindividual variation. Biological variation generally accounted for more of total intraindividual variation than did assay variation. Day-to-day biological variation accounted for more of the total than did long-term biological variation. Short-term variability was greater in hormones with pulsatile secretion (e.g. LH) than those that exhibit less ultradian variation. Depending on the hormone, the intraindividual standard deviations imply that a clinician can expect to see a difference exceeding 18-28% about half the time when two measurements are made on a subject. The difference will exceed 27-54% about a quarter of the time. Given the level of intraindividual variability in hormone

Comparison of third and second generation parathyroid hormone assays and their use in chronic hemdialysis patients

Directory of Open Access Journals (Sweden)

Alexis Muryan

2017-06-01

Full Text Available Introduction: This work’s objective is to compare third and second generation assays in patients with normal kidney function and in chronic hemodialysis patients, and the implications on the latter. Methods: 60 chronic hemodialysis patients and 40 patients with normal kidney function were studied and their PTH levels were measured for both assays. Results: In patients population with normal kidney function the average on PTH was 51.8 and 45.6 pg/ml with second and third generation assays respectively. In chronic hemodialysis patients the average PTH was 193.9 and 137.1 pg/ml with second and third generation assays respectively. The difference between assays was 11.3% and 29.3% in patients with normal kidney function and in hemodialysis patients respectively. Third generation assay caused a variation in the amount of patients that fall over seve ral PTH ranges according to KDIGO guidelines, for a lesser value of 2 times the reference upper limit: it changes from 20 to 25 patients, between 2 and 9 times: it changes from 31 to 32 patients, and more than 9 times: it changes from 9 to 3 patients. Conclusions: When PTH concentration increases the difference between both assays also increases, for this reason we cannot use them indiscriminately in a chronic hemodialysis patient population. With third generation assays 11 patients (18.3% changed their classification according to KDIGO guidelines, which will result in a change of treatment.

Novel cell-based assay for detection of thyroid receptor beta-interacting environmental contaminants.

Science.gov (United States)

Stavreva, Diana A; Varticovski, Lyuba; Levkova, Ludmila; George, Anuja A; Davis, Luke; Pegoraro, Gianluca; Blazer, Vicki; Iwanowicz, Luke; Hager, Gordon L

2016-08-10

Even though the presence of endocrine disrupting chemicals (EDCs) with thyroid hormone (TH)-like activities in the environment is a major health concern, the methods for their efficient detection and monitoring are still limited. Here we describe a novel cell assay, based on the translocation of a green fluorescent protein (GFP)-tagged chimeric molecule of glucocorticoid receptor (GR) and the thyroid receptor beta (TRβ) from the cytoplasm to the nucleus in the presence of TR ligands. Unlike the constitutively nuclear TRβ, this GFP-GR-TRβ chimera is cytoplasmic in the absence of hormone while translocating to the nucleus in a time- and concentration-dependent manner upon stimulation with triiodothyronine (T3) and thyroid hormone analogue, TRIAC, while the reverse triiodothyronine (3,3',5'-triiodothyronine, or rT3) was inactive. Moreover, GFP-GR-TRβ chimera does not show any cross-reactivity with the GR-activating hormones, thus providing a clean system for the screening of TR beta-interacting EDCs. Using this assay, we demonstrated that Bisphenol A (BPA) and 3,3',5,5'-Tetrabromobisphenol (TBBPA) induced GFP-GR-TRβ translocation at micro molar concentrations. We screened over 100 concentrated water samples from different geographic locations in the United States and detected a low, but reproducible contamination in 53% of the samples. This system provides a novel high-throughput approach for screening for endocrine disrupting chemicals (EDCs) interacting with TR beta. Published by Elsevier Ireland Ltd.

Novel cell-based assay for detection of thyroid receptor beta-interacting environmental contaminants

International Nuclear Information System (INIS)

Stavreva, Diana A.; Varticovski, Lyuba; Levkova, Ludmila; George, Anuja A.; Davis, Luke; Pegoraro, Gianluca; Blazer, Vicki; Iwanowicz, Luke; Hager, Gordon L.

2016-01-01

Even though the presence of endocrine disrupting chemicals (EDCs) with thyroid hormone (TH)-like activities in the environment is a major health concern, the methods for their efficient detection and monitoring are still limited. Here we describe a novel cell assay, based on the translocation of a green fluorescent protein (GFP)—tagged chimeric molecule of glucocorticoid receptor (GR) and the thyroid receptor beta (TRβ) from the cytoplasm to the nucleus in the presence of TR ligands. Unlike the constitutively nuclear TRβ, this GFP-GR-TRβ chimera is cytoplasmic in the absence of hormone while translocating to the nucleus in a time- and concentration-dependent manner upon stimulation with triiodothyronine (T3) and thyroid hormone analogue, TRIAC, while the reverse triiodothyronine (3,3′,5′-triiodothyronine, or rT3) was inactive. Moreover, GFP-GR-TRβ chimera does not show any cross-reactivity with the GR-activating hormones, thus providing a clean system for the screening of TR beta-interacting EDCs. Using this assay, we demonstrated that Bisphenol A (BPA) and 3,3′,5,5′-Tetrabromobisphenol (TBBPA) induced GFP-GR-TRβ translocation at micro molar concentrations. We screened over 100 concentrated water samples from different geographic locations in the United States and detected a low, but reproducible contamination in 53% of the samples. This system provides a novel high-throughput approach for screening for endocrine disrupting chemicals (EDCs) interacting with TR beta.

Rapid, portable detection of endocrine disrupting chemicals through ligand-nuclear hormone receptor interactions.

Science.gov (United States)

Hunt, J Porter; Schinn, Song-Min; Jones, Matthew D; Bundy, Bradley C

2017-12-04

Endocrine disrupting chemicals (EDC) are structurally diverse compounds that can interact with nuclear hormone receptors, posing significant risk to human and ecological health. Unfortunately, many conventional biosensors have been too structure-specific, labor-intensive or laboratory-oriented to detect broad ranges of EDC effectively. Recently, several technological advances are providing more rapid, portable, and affordable detection of endocrine-disrupting activity through ligand-nuclear hormone receptor interactions. Here, we overview these recent advances applied to EDC biosensors - including cell lyophilization, cell immobilization, cell-free systems, smartphone-based signal detection, and improved competitive binding assays.

Quantification of three steroid hormone receptors of the leopard gecko (Eublepharis macularius), a lizard with temperature-dependent sex determination: their tissue distributions and the effect of environmental change on their expressions.

Science.gov (United States)

Endo, Daisuke; Park, Min Kyun

2003-12-01

Sex steroid hormones play a central role in the reproduction of all vertebrates. These hormones function through their specific receptors, so the expression levels of the receptors may reflect the responsibility of target organs. However, there was no effective method to quantify the expression levels of these receptors in reptilian species. In this study, we established the competitive-PCR assay systems for the quantification of the mRNA expression levels of three sex steroid hormone receptors in the leopard gecko. These assay systems were successfully able to detect the mRNA expression level of each receptor in various organs of male adult leopard geckoes. The expression levels of mRNA of these receptors were highly various depending on the organs assayed. This is the first report regarding the tissue distributions of sex steroid hormone receptor expressions in reptile. The effects of environmental conditions on these hormone receptor expressions were also examined. After the low temperature and short photoperiod treatment for 6 weeks, only the androgen receptor expression was significantly increased in the testes. The competitive-PCR assay systems established in this report should be applicable for various studies of the molecular mechanism underlying the reproductive activity of the leopard gecko.

Thyroid endocrine system disruption by pentachlorophenol: an in vitro and in vivo assay.

Science.gov (United States)

Guo, Yongyong; Zhou, Bingsheng

2013-10-15

The present study aimed to evaluate the disruption caused to the thyroid endocrine system by pentachlorophenol (PCP) using in vitro and in vivo assays. In the in vitro assay, rat pituitary GH3 cells were exposed to 0, 0.1, 0.3, and 1.0 μM PCP. PCP exposure significantly downregulated basal and triiodothyronine (T3)-induced Dio 1 transcription, indicating the antagonistic activity of PCP in vitro. In the in vivo assay, zebrafish embryos were exposed to 0, 1, 3, and 10 μg/L of PCP until 14 days post-fertilization. PCP exposure resulted in decreased thyroxine (T4) levels, but elevated contents of whole-body T3. PCP exposure significantly upregulated the mRNA expression of genes along hypothalamic-pituitary-thyroid (HPT) axis, including those encoding thyroid-stimulating hormone, sodium/iodide symporter, thyroglobulin, Dio 1 and Dio 2, alpha and beta thyroid hormone receptor, and uridinediphosphate-glucuronosyl-transferase. PCP exposure did not influence the transcription of the transthyretin (TTR) gene. The results indicate that PCP potentially disrupts the thyroid endocrine system both in vitro and in vivo. Copyright © 2013 Elsevier B.V. All rights reserved.

Radioimmunoassay of bovine, ovine and porcine luteinizing hormone with a monoclonal antibody and a human tracer

Energy Technology Data Exchange (ETDEWEB)

Fosberg, M; Tagle, R; Madej, A; Molina, J R; Carlsson, M -A

1993-01-01

A radioimmunoassay for bovine (bLH), ovine (oLH) and porcine (pLH) luteinizing hormone was developed using a human [sup 125]ILH tracer from a commercial kit and a monoclonal antibody (518B7) specific for LH but with low species specificity. Standard curves demonstrated similar binding kinetics when bLH, oLH and pLH were incubated with tracer and antibody for 2 h at room temperature. A 30-min delay in the addition of the tracer gave sufficient sensitivity when analysing pLH. Separation of antibody-bound LH from free hormone was achieved by using second antibody-coated micro Sepharose beads. The assay was validated and the performance compared with that of an RIA currently in use for determination of bLH (coefficient of correlation: 0.99 and 0.98). Regardless of the standards used, intra-assay coefficients of variation were <10% for LH concentrations exceeding 1 [mu]g/L. The inter-assay coefficients of variation were <15%. The assay was used for clinical evaluation demonstrating the pre-ovulatory LH surge in two cyclic cows, LH pulsatility in an oophorectomized ewe and LH response to GnRH injection in a boar. (au) (7 refs.).

Technical note: Time-resolved immunofluorometric assay for growth hormone in ruminants

DEFF Research Database (Denmark)

Løvendahl, P.; Adamsen, J.; Lund, Regina Teresa

2003-01-01

for 4 h at 25degreesC. Plates were then washed six times, incubated for 5 to 10 min with 250 muL of enhancement solution, and fluorescence read with a time-resolved fluorometer. The sensitivity of the assay was 0.1 ng/mL, and the working range was 0.2 to 200 ng/mL. Recovery of quantitative amounts...

Pentadecapeptide BPC 157 Enhances the Growth Hormone Receptor Expression in Tendon Fibroblasts

Directory of Open Access Journals (Sweden)

Chung-Hsun Chang

2014-11-01

Full Text Available BPC 157, a pentadecapeptide derived from human gastric juice, has been demonstrated to promote the healing of different tissues, including skin, muscle, bone, ligament and tendon in many animal studies. However, the underlying mechanism has not been fully clarified. The present study aimed to explore the effect of BPC 157 on tendon fibroblasts isolated from Achilles tendon of male Sprague-Dawley rat. From the result of cDNA microarray analysis, growth hormone receptor was revealed as one of the most abundantly up-regulated genes in tendon fibroblasts by BPC 157. BPC 157 dose- and time-dependently increased the expression of growth hormone receptor in tendon fibroblasts at both the mRNA and protein levels as measured by RT/real-time PCR and Western blot, respectively. The addition of growth hormone to BPC 157-treated tendon fibroblasts dose- and time-dependently increased the cell proliferation as determined by MTT assay and PCNA expression by RT/real-time PCR. Janus kinase 2, the downstream signal pathway of growth hormone receptor, was activated time-dependently by stimulating the BPC 157-treated tendon fibroblasts with growth hormone. In conclusion, the BPC 157-induced increase of growth hormone receptor in tendon fibroblasts may potentiate the proliferation-promoting effect of growth hormone and contribute to the healing of tendon.

Stress hormones predict hyperbolic time-discount rates six months later in adults.

Science.gov (United States)

Takahashi, Taiki; Shinada, Mizuho; Inukai, Keigo; Tanida, Shigehito; Takahashi, Chisato; Mifune, Nobuhiro; Takagishi, Haruto; Horita, Yutaka; Hashimoto, Hirofumi; Yokota, Kunihiro; Kameda, Tatsuya; Yamagishi, Toshio

2010-01-01

Stress hormones have been associated with temporal discounting. Although time-discount rate is shown to be stable over a long term, no study to date examines whether individual differences in stress hormones could predict individuals' time-discount rates in the relatively distant future (e.g., six month later), which is of interest in neuroeconomics of stress-addiction association. We assessed 87 participants' salivary stress hormone (cortisol, cortisone, and alpha-amylase) levels and hyperbolic discounting of delayed rewards consisting of three magnitudes, at the time-interval of six months. For salivary steroid assays, we employed a liquid chromatography/ mass spectroscopy (LC/MS) method. The correlations between the stress hormone levels and time-discount rates were examined. We observed that salivary alpha-amylase (sAA) levels were negatively associated with time-discount rates in never-smokers. Notably, salivary levels of stress steroids (i.e., cortisol and cortisone) negatively and positively related to time-discount rates in men and women, respectively, in never-smokers. Ever-smokers' discount rates were not predicted from these stress hormone levels. Individual differences in stress hormone levels predict impulsivity in temporal discounting in the future. There are sex differences in the effect of stress steroids on temporal discounting; while there was no sex defference in the relationship between sAA and temporal discounting.

Preeclampsia-Associated Hormonal Profiles and Reduced Breast Cancer Risk Among Older Mothers

National Research Council Canada - National Science Library

Laudenslager, Mark

2003-01-01

... to cases on race/ethnicity, current age, age at delivery, and breast-feeding status. A fasting blood and saliva sample was collected from each subject during the luteal phase (day 19-22) of the menstrual cycle and assayed for specific steroid and peptide hormones thought to be linked to breast cancer.

Radioimmunoassay for luteinizing hormone releasing hormone in plasma

International Nuclear Information System (INIS)

Saito, Shiro; Musa, Kimitaka; Oshima, Ichiyo; Yamamoto, Suzuyo; Funato, Toyohiko

1975-01-01

A sensitive and specific double antibody radioimmunoassay has been developed capable of measuring LH-RH in extracted human plasma. Thyrotropin releasing hormone, lysine vasopressin and most of LH-RH analogues did not appear to affect the assay. Hypothalamic extract and some of the LH-RH analogues produced displacement curves which were parallel to the curve obtained with the synthetic LH-RH. Sensitivity of the radioimmunoassay was about 3 pg per assay tube. The coefficient of variation of intraassays was 6.4%, while that of interassays was 9.6%. Exogenous LH-RH could be quantitatively extracted by acidic ethanol when varying amounts of synthetic LH-RH were added to the plasma. Immunoreactivity of LH-RH was preserved in plasma for 2 hrs in the cold but was gradually reduced thereafter. The plasma levels of LH-RH were 20 pg/ml or less in normal adults and not detectable in children. Aged males over 60 yr and postmenopausal women showed a tendency to have higher levels of plasma LH-RH. The plasma LH-RH level was significantly higher in midcycle than in the follicular or luteal stages. The disappearance rate of LH-RH from the circulation after intravenous injection could be represented as half-times of 4-6 min. Between 0.2-0.4% of the injected dose was excreted into urine within 1 hr. These results indicate that the determination of LH-RH might be a useful tool for elucidating hypothalamic-pituitary-gonad interactions. (auth.)

Benzodiazepines have high-affinity binding sites and induce melanogenesis in B16/C3 melanoma cells.

OpenAIRE

Matthew, E; Laskin, J D; Zimmerman, E A; Weinstein, I B; Hsu, K C; Engelhardt, D L

1981-01-01

We found that two markers of differentiation, tyrosinase (monophenol, dihydroxyphenylalanine:oxygen oxidoreductase, EC 1.14.18.1) activity and melanin synthesis, are induced by diazepam in B16/C3 mouse melanoma cells. We also demonstrated high-affinity binding sites for [3H]diazepam in these cells by radioreceptor assay, and we visualized binding to the cell surface by fluorescence microscopy with a benzodiazepine analog conjugated to a fluorescein-labeled protein. Our studies also showed tha...

Plasma. beta. -endorphin and stress hormone levels during adaptation and stress

Energy Technology Data Exchange (ETDEWEB)

Lishmanov, Yu.B.; Trifonova, Zh.V.; Tsibin, A.N.; Maslova, L.V.; Dement' eva, L.A.

1987-09-01

This paper describes a comparative study of ..beta..-endorphin and stress hormone levels in the blood plasma of rats during stress and adaptation. Immunoreactive ..beta..-endorphin in the blood plasma was assayed by means of a kit after preliminary isolation of the ..beta..-endorphin fraction by affinity chromatography on sepharose; ACTH was assayed with a kit and cortisol, insulin, thyroxine and tri-iodothyronine by means of kits from Izotop. Determination of plasma levels of ..beta..-endorphin and other opioids could evidently be an important method of assessing the state of resistance of the organism to stress.

Recovery responses of testosterone, growth hormone, and IGF-1 after resistance exercise.

Science.gov (United States)

Kraemer, William J; Ratamess, Nicholas A; Nindl, Bradley C

2017-03-01

The complexity and redundancy of the endocrine pathways during recovery related to anabolic function in the body belie an oversimplistic approach to its study. The purpose of this review is to examine the role of resistance exercise (RE) on the recovery responses of three major anabolic hormones, testosterone, growth hormone(s), and insulin-like growth factor 1. Each hormone has a complexity related to differential pathways of action as well as interactions with binding proteins and receptor interactions. Testosterone is the primary anabolic hormone, and its concentration changes during the recovery period depending on the upregulation or downregulation of the androgen receptor. Multiple tissues beyond skeletal muscle are targeted under hormonal control and play critical roles in metabolism and physiological function. Growth hormone (GH) demonstrates differential increases in recovery with RE based on the type of GH being assayed and workout being used. IGF-1 shows variable increases in recovery with RE and is intimately linked to a host of binding proteins that are essential to its integrative actions and mediating targeting effects. The RE stress is related to recruitment of muscle tissue with the glandular release of hormones as signals to target tissues to support homeostatic mechanisms for metabolism and tissue repair during the recovery process. Anabolic hormones play a crucial role in the body's response to metabolism, repair, and adaptive capabilities especially in response to anabolic-type RE. Changes of these hormones following RE during recovery in the circulatory biocompartment of blood are reflective of the many mechanisms of action that are in play in the repair and recovery process. Copyright © 2017 the American Physiological Society.

Removal of natural hormones in dairy farm wastewater using reactive and sorptive materials.

Science.gov (United States)

Cai, Kai; Phillips, Debra H; Elliott, Christopher T; Muller, Marc; Scippo, Marie-Louise; Connolly, Lisa

2013-09-01

The objective of this study was to examine the oestrogen and androgen hormone removal efficiency of reactive (Connelly zero-valent iron (ZVI), Gotthart Maier ZVI) and sorptive (AquaSorb 101 granular activated carbon (GAC) and OrganoLoc PM-100 organoclay (OC)) materials from HPLC grade water and constructed wetland system (CWS) treated dairy farm wastewater. Batch test studies were performed and hormone concentration analysis carried out using highly sensitive reporter gene assays (RGAs). The results showed that hormonal interaction with these materials is selective for individual classes of hormones. Connelly ZVI and AquaSorb 101 GAC were more efficient in removing testosterone (Te) than 17β-estradiol (E2) and showed faster removal rates of oestrogen and androgen than the other materials. Gotthart Maier ZVI was more efficient in removing E2 than Te. OrganoLoc PM-100 OC achieved the lowest final concentration of E2 equivalent (EEQ) and provided maximum removal of both oestrogens and androgens. Copyright © 2013 Elsevier B.V. All rights reserved.

Standardization of human thyrotropin radioimmunoassay and its application to the purification of this hormone to the preparation of the assay reagents

International Nuclear Information System (INIS)

Lin, L.H.

1991-01-01

The various steps that are necessary for setting up the thyrotropin radioimmunoassay are presented below. Radioiodination was carried out through the Chloramine T method and the labeled purification performed on Sephadex G-100. Purification of human thyrotropin from side fractions obtained during the purification of growth hormone was carried out in order to obtain a pure reagent for use in the radioimmunoassay. The employment of the hormone obtained was evaluated as the radioimmunoassay tracer in comparison with that prepared from the hormone received from the NIDDKD, U.S.A. The results indicated that although it was not possible to obtain a hormone with a purity degree adequate to be used as the tracer, enough experience was acquired for the isolation of thyrotropin. (author)

Nuclear Import and Export of the Thyroid Hormone Receptor.

Science.gov (United States)

Zhang, Jibo; Roggero, Vincent R; Allison, Lizabeth A

2018-01-01

The thyroid hormone receptors, TRα1 and TRβ1, are members of the nuclear receptor superfamily that forms one of the most abundant classes of transcription factors in multicellular organisms. Although primarily localized to the nucleus, TRα1 and TRβ1 shuttle rapidly between the nucleus and cytoplasm. The fine balance between nuclear import and export of TRs has emerged as a critical control point for modulating thyroid hormone-responsive gene expression. Mutagenesis studies have defined two nuclear localization signal (NLS) motifs that direct nuclear import of TRα1: NLS-1 in the hinge domain and NLS-2 in the N-terminal A/B domain. Three nuclear export signal (NES) motifs reside in the ligand-binding domain. A combined approach of shRNA-mediated knockdown and coimmunoprecipitation assays revealed that nuclear entry of TRα1 is facilitated by importin 7, likely through interactions with NLS-2, and importin β1 and the adapter importin α1 interacting with both NLS-1 and NLS-2. Interestingly, TRβ1 lacks NLS-2 and nuclear import depends solely on the importin α1/β1 heterodimer. Heterokaryon and fluorescence recovery after photobleaching shuttling assays identified multiple exportins that play a role in nuclear export of TRα1, including CRM1 (exportin 1), and exportins 4, 5, and 7. Even single amino acid changes in TRs dramatically alter their intracellular distribution patterns. We conclude that mutations within NLS and NES motifs affect nuclear shuttling activity, and propose that TR mislocalization contributes to the development of some types of cancer and Resistance to Thyroid Hormone syndrome. © 2018 Elsevier Inc. All rights reserved.

Strigolactones, a novel carotenoid-derived plant hormone

KAUST Repository

Al-Babili, Salim

2015-04-29

Strigolactones (SLs) are carotenoid-derived plant hormones and signaling molecules. When released into the soil, SLs indicate the presence of a host to symbiotic fungi and root parasitic plants. In planta, they regulate several developmental processes that adapt plant architecture to nutrient availability. Highly branched/tillered mutants in Arabidopsis, pea, and rice have enabled the identification of four SL biosynthetic enzymes: a cis/trans-carotene isomerase, two carotenoid cleavage dioxygenases, and a cytochrome P450 (MAX1). In vitro and in vivo enzyme assays and analysis of mutants have shown that the pathway involves a combination of new reactions leading to carlactone, which is converted by a rice MAX1 homolog into an SL parent molecule with a tricyclic lactone moiety. In this review, we focus on SL biosynthesis, describe the hormonal and environmental factors that determine this process, and discuss SL transport and downstream signaling as well as the role of SLs in regulating plant development. ©2015 by Annual Reviews. All rights reserved.

Study of goldfish (Carassius auratus) growth hormone structure-function relationship by domain swapping.

Science.gov (United States)

Chan, Y H; Cheng, C H K; Chan, K M

2007-03-01

Using goldfish as a model, the structure-function relationship of goldfish growth hormone was studied using the strategy of homologous domain swapping. Chimeric mutants were constructed by exchanging homologous regions between goldfish growth hormone (gfGH II) and goldfish prolactin (gfPRL) with their cloned complementary DNAs. Six mutants, with their domain-swapped, were generated to have different combinations of three target regions, including the helix a, helix d and the large section in between these helices (possess the helices b, c and other random coiled regions). After expression in E. coli and refolding, these mutants were characterized by using competitive receptor binding assay (RRA) and growth hormone responding promoter activation assay. The different activity profiles of mutants in Spi 2.1 gene promoter assays from that in RRA shows that, for gfGH, receptor binding dose not confer receptor signal activations. When either helices a or d of gfGH was maintained with other helices replaced by their gfPRL counterparts, both receptor binding and hence gene activation activities are reduced. In mutants with helices b and c in gfGH maintained, containing the gfGH middle section, and helices a and d swapped with gfPRL, the had reduced RRA activities but the promoter activation activities retained. In conclusion, as in the case of human GH, the gfGH molecule possesses two functional sites: one of them is composed of discontinuous epitopes located on the target regions of this study and is for receptor binding; another site is located on the middle section of the molecule that helices a and d are not involved, and it is for activation of GH receptor and intracellular signals.

The evaluation of CLIA, RIA and MSP-ELISA for measurement of thyroid hormones

International Nuclear Information System (INIS)

Jing Hua; Li Dan; Chen Yiguang; Zhou Huiqin; Xu Liyan

2005-01-01

To compare the characteristics of chemiluminescent immunoassay (CLIA), RIA and magnetic solid phase enzyme-linked immnosorbent assay (MSP-ELISA) in measuring thyroid hormones, TT 3 , TT 4 , FT 3 , FT 4 and TSH were tested in 40 samples of human serum and in standard samples of thyroid hormones by CLIA, RIA and MSP-ELISA respectively. The linearity, relativiy, precision, recovery of these three met hods were compared. The result showed that there were no statistical differences between CLIA, RIA and MSP-ELISA in linearity and relativity. CLIA was better than RIA and MSP-ELISA in precision and accuracy. (authors)

Association of postmenopausal endogenous sex hormones with global methylation level of leukocyte DNA among Japanese women

Directory of Open Access Journals (Sweden)

Iwasaki Motoki

2012-07-01

Full Text Available Abstract Background Although global hypomethylation of leukocyte DNA has been associated with an increased risk of several sites of cancer, including breast cancer, determinants of global methylation level among healthy individuals remain largely unexplored. Here, we examined whether postmenopausal endogenous sex hormones were associated with the global methylation level of leukocyte DNA. Methods A cross-sectional study was conducted using the control group of a breast cancer case–control study in Nagano, Japan. Subjects were postmenopausal women aged 55 years or over who provided blood samples. We measured global methylation level of peripheral blood leukocyte DNA by luminometric methylation assay; estradiol, estrone, androstenedione, dehydroepiandrosterone sulfate, testosterone and free testosterone by radioimmunoassay; bioavailable estradiol by the ammonium sulfate precipitation method; and sex-hormone binding globulin by immunoradiometric assay. A linear trend of association between methylation and hormone levels was evaluated by regression coefficients in a multivariable liner regression model. A total of 185 women were included in the analyses. Results Mean global methylation level (standard deviation was 70.3% (3.1 and range was from 60.3% to 79.2%. Global methylation level decreased 0.27% per quartile category for estradiol and 0.39% per quartile category for estrone while it increased 0.41% per quartile category for bioavailable estradiol. However, we found no statistically significant association of any sex hormone level measured in the present study with global methylation level of leukocyte DNA. Conclusions Our findings suggest that endogenous sex hormones are not major determinants of the global methylation level of leukocyte DNA.

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

Persistent organochlorine pollutants with endocrine activity and blood steroid hormone levels in middle-aged men.

Directory of Open Access Journals (Sweden)

Elise Emeville

Full Text Available BACKGROUND: Studies relating long-term exposure to persistent organochlorine pollutants (POPs with endocrine activities (endocrine disrupting chemicals on circulating levels of steroid hormones have been limited to a small number of hormones and reported conflicting results. OBJECTIVE: We examined the relationship between serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulphate, androstenedione, androstenediol, testosterone, free and bioavailable testosterone, dihydrotestosterone, estrone, estrone sulphate, estradiol, sex-hormone binding globulin, follicle-stimulating hormone, and luteinizing hormone as a function of level of exposure to three POPs known to interfere with hormone-regulated processes in different way: dichlorodiphenyl dichloroethene (DDE, polychlorinated biphenyl (PCB congener 153, and chlordecone. METHODS: We collected fasting, morning serum samples from 277 healthy, non obese, middle-aged men from the French West Indies. Steroid hormones were determined by gas chromatography-mass spectrometry, except for dehydroepiandrosterone sulphate, which was determined by immunological assay, as were the concentrations of sex-hormone binding globulin, follicle-stimulating hormone and luteinizing hormone. Associations were assessed by multiple linear regression analysis, controlling for confounding factors, in a backward elimination procedure, in multiple bootstrap samples. RESULTS: DDE exposure was negatively associated to dihydrotestosterone level and positively associated to luteinizing hormone level. PCB 153 was positively associated to androstenedione and estrone levels. No association was found for chlordecone. CONCLUSIONS: These results suggested that the endocrine response pattern, estimated by determining blood levels of steroid hormones, varies depending on the POPs studied, possibly reflecting differences in the modes of action generally attributed to these compounds. It remains to be investigated whether

Preparation and Characterization of an Antibody Antagonist That Targets the Porcine Growth Hormone Receptor

Directory of Open Access Journals (Sweden)

Huanzhong Cui

2016-10-01

Full Text Available A series of antagonists specifically targeting growth hormone receptors (GHR in different species, such as humans, rats, bovines, and mice, have been designed; however, there are currently no antagonists that target the porcine growth hormone (GH. Therefore, in this study, we developed and characterized a porcine GHR (pGHR antibody antagonist (denoted by AN98 via the hybridoma technique. The results from enzyme-linked immunosorbent assay, fluorescence activated cell sorter, indirect immunoinfluscent assay, and competitive receptor binding analysis showed that AN98 could specifically recognize pGHR, and further experiments indicated that AN98 could effectively inhibit pGH-induced signalling in CHO-pGHR cells and porcine hepatocytes. In addition, AN98 also inhibited GH-induced insulin-like growth factor-1 (IGF-1 secretion in porcine hepatocytes. In summary, these findings indicated that AN98, as a pGHR-specific antagonist, has potential applications in pGH-pGHR-related research on domestic pigs.

Concentrations of testosterone, luteal hormone and prolactin in the serum as well as comparisons of sensitivity between radioimmunoassays and enzyme assays for the detection of acid prostate phosphatase in the presence of carcinomas of the prostate

International Nuclear Information System (INIS)

Vopelius-Feldt, F. von.

1986-01-01

The relationship between carcinomas of the prostate and the plasma levels of testosterone, luteal hormone and prolactin as well as the possible influence of these neoplasms on the testosterone binding capacity and free testosterone index are investigated for various tumour stages and degrees of histological differentiation, in connection with several forms of local therapy as well as a variety of contrasexual methods. The sensitivity of enzyme assays and radioimmunoassays for the detection of acid prostate phosphatase is evaluated within the framework of this study. (MBL) [de

Associations between Bisphenol A Exposure and Reproductive Hormones among Female Workers.

Science.gov (United States)

Miao, Maohua; Yuan, Wei; Yang, Fen; Liang, Hong; Zhou, Zhijun; Li, Runsheng; Gao, Ersheng; Li, De-Kun

2015-10-22

The associations between Bisphenol-A (BPA) exposure and reproductive hormone levels among women are unclear. A cross-sectional study was conducted among female workers from BPA-exposed and unexposed factories in China. Women's blood samples were collected for assay of follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17β-Estradiol (E2), prolactin (PRL), and progesterone (PROG). Their urine samples were collected for BPA measurement. In the exposed group, time weighted average exposure to BPA for an 8-h shift (TWA8), a measure incorporating historic exposure level, was generated based on personal air sampling. Multiple linear regression analyses were used to examine linear associations between urine BPA concentration and reproductive hormones after controlling for potential confounders. A total of 106 exposed and 250 unexposed female workers were included in this study. A significant positive association between increased urine BPA concentration and higher PRL and PROG levels were observed. Similar associations were observed after the analysis was carried out separately among the exposed and unexposed workers. In addition, a positive association between urine BPA and E2 was observed among exposed workers with borderline significance, while a statistically significant inverse association between urine BPA and FSH was observed among unexposed group. The results suggest that BPA exposure may lead to alterations in female reproductive hormone levels.

Associations between Bisphenol A Exposure and Reproductive Hormones among Female Workers

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Maohua Miao

2015-10-01

Full Text Available The associations between Bisphenol-A (BPA exposure and reproductive hormone levels among women are unclear. A cross-sectional study was conducted among female workers from BPA-exposed and unexposed factories in China. Women’s blood samples were collected for assay of follicle-stimulating hormone (FSH, luteinizing hormone (LH, 17β-Estradiol (E2, prolactin (PRL, and progesterone (PROG. Their urine samples were collected for BPA measurement. In the exposed group, time weighted average exposure to BPA for an 8-h shift (TWA8, a measure incorporating historic exposure level, was generated based on personal air sampling. Multiple linear regression analyses were used to examine linear associations between urine BPA concentration and reproductive hormones after controlling for potential confounders. A total of 106 exposed and 250 unexposed female workers were included in this study. A significant positive association between increased urine BPA concentration and higher PRL and PROG levels were observed. Similar associations were observed after the analysis was carried out separately among the exposed and unexposed workers. In addition, a positive association between urine BPA and E2 was observed among exposed workers with borderline significance, while a statistically significant inverse association between urine BPA and FSH was observed among unexposed group. The results suggest that BPA exposure may lead to alterations in female reproductive hormone levels.

Similarity criterion analysis of dose-response curves in biological assay and radioimmunoassay of hormones

International Nuclear Information System (INIS)

Cristakou, H.D.

1983-01-01

The difficulties involved in the control of biological and radioimmunological assay systems, and in the maintenance of standard, as well as, the usual heterogeneity of assayed samples require some evidence of similarity between the dose-response curves obtained with the standard and the sample. Nowadays the parallelism test is used to provide such evidence. However, some indications of non-normal errors distribution, such as the presence of out layers, render the parallelism test both conceptually implausible and statistically inefficient. In such a manner we suggest the non-parametric 'frequencial' test as a more sounding option. (author)

Reproductive Hormones and Subclinical Cardiovascular Disease in Midlife Women.

Science.gov (United States)

Thurston, Rebecca C; Bhasin, Shalender; Chang, Yuefang; Barinas Mitchell, Emma; Matthews, Karen A; Jasuja, Ravi; Santoro, Nanette

2018-05-18

Reproductive hormones are understood to be important to the pathophysiology of cardiovascular disease (CVD) in women. However, standard estradiol (E2) and testosterone (T) assays lack sensitivity at the levels of postmenopausal women. Investigate relations of mass spectrometry-assessed estrone (E1), estradiol (E2), and testosterone (T), and sex hormone binding globulin (SHBG) and subclinical CVD in women. 304 peri- and postmenopausal women, aged 40-60 years, and free of clinical CVD underwent subclinical CVD measurements. E1, E2, and T were assayed using liquid chromatography-tandem mass spectrometry; Free T (FT) was estimated using ensemble allostery models. Associations between hormones and outcomes were analyzed using regression models adjusting for CVD risk factors. Carotid artery intima media thickness (IMT), inter-adventitial diameter (IAD), plaque; brachial flow mediated dilation (FMD). Higher E1 was related to higher FMD [b(SE)=.77(.37), p=.04], indicating better endothelial function. Higher E2 was related to lower IAD [b(SE)=-.07(.02), p=.004], indicating less carotid remodeling. Higher SHBG was related to higher FMD [b(SE)=1.31(.40), p=.001], yet higher IAD [b(SE)=.15(.06), p=.02] and carotid plaque [OR (95%CI)=1.84(1.16-2.91), p=.009]. Higher FT was associated with lower FMD [b(SE)=-1.58(.52), p=.003], yet lower IAD [b(SE)=-.19(.08), p=.01] and carotid plaque [OR(95%CI)=.49(.28-.88), p=.02]. Thus, higher SHBG and lower FT was associated with better endothelial function, yet greater carotid remodeling and plaque. Endogenous E1 levels were related to endothelial function and E2 to vascular remodeling, suggesting distinct roles of these estrogens. SHBG and free testosterone have a complex role and depend on the vessel under study.

Radioimmunossay of hormones and metabolites in blood serum and plasma

International Nuclear Information System (INIS)

Khare, G.P.

1978-01-01

Hormones or metabolites which are capable of producing antibodies can be detected and precisely quantitated by this method. Antibodies, to various hormones or metabolites whose assay is desired, are adsorbed onto commercially available imitation or cultured pearls. These pearls coated with antibody are contacted with a buffered reaction mixture containing blood serum or plasma specimen and respective radioactive antigen. The entire reaction is allowed to proceed for a time sufficient to form antigen (radioactive or non-radioactive)-antibody complex. These complexes on the pearls are washed and the total amount of radioactivity emanating from the complex is measured. This is indicative of the extent of binding of radioactive antigen and provides an indirect correlation of the amount of non-radioactive antigen present in the serum or plasma sample

Adrenocorticotropin, beta-endorphin, and beta-lipotropin in normal thyroid and lung: possible implications for ectopic hormone secretion.

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Clements, J A; Funder, J W; Tracy, K; Morgan, F J; Campbell, D J; Lewis, P; Hearn, M T

1982-12-01

The expression of the proopiomelanocortin (POMC) gene by normal lung and thyroid was examined by measurement of the content of ACTH, beta-lipotropin (beta LPH), and beta-endorphin (beta EP) in porcine lung and thyroid tissue. Acid extracts of normal porcine lung and thyroid tissue each contained appreciable amounts of immunoreactive (ir) ACTH, ir-beta LPH, and ir-beta EP. The content of ir-beta LPH in both tissues exceeded by severalfold, on a molar basis, the content of ir-ACTH and ir-beta EP, suggesting that the common precursor POMC was processed predominantly to peptides other than ir-ACTH and ir-beta EP. A porcine thyroid extract (Calcitare, porcine calcitonin, Armour) showed equivalent levels of beta EP-like immunoreactivity and bioactivity, measured by opiate radioreceptor assay; in contrast, ACTH-like bioactivity, measured by rat zona fasciculata steroidogenesis, was only 4% of ACTH-like immunoreactivity. On reversed phase high performance liquid chromatography, Calcitare showed multiple peaks of ACTH-like immunoreactivity, one of which coeluted with porcine ACTH-(1-39), and two much smaller peaks of beta EP-like immunoreactivity, of which the smaller coeluted with porcine beta EP. These data suggest that both lung and thyroid gland synthesize POMC, which in normal tissue is usually predominantly processed to species other than ACTH and beta EP. Ectopic secretion of ACTH and beta EP by lung and thyroid neoplasms may thus represent the loss of a system(s) normally responsible for processing the precursor beyond ACTH and beta EP.

Bioactivity and immunoactivity of growth hormone during dynamic testing of patients with acromegaly

International Nuclear Information System (INIS)

Baldwin, A.L.; Norman, M.; Butler, J.; Aston, R.; Buchanan, C.

1988-01-01

We have used the Nb2 cell proliferation bioassay for lactogenic hormones to investigate the biological activity of hGH in sera of patients with acromegaly. The specificity of the assay has been improved by the use of monoclonal antibodies to block the activity of individual lactogenic hormones. Disease activity in patients was assessed by scoring signs and symptoms, and by measuring IGF-I concentrations in some patients. Patients with a wide spectrum of disease activity were studied using a TRH test. hGH concentrations were measured by bioassay, RIA and immunoradiometric assay (IRMA) at 0,20 and 60 min after injection of TRH. There was a high degree of correlation between log 10 of all hGH concentrations measured by bioassay and RIA (r = 0.995, P<0.0001), between bioassay and IRMA (r = 0.990, P<0.0001), and between RIA and IRMA (r = 0.995, P<0.0001). In contrast to previous reports, we found no evidence for changes in the bioactivity of hGH secreted after pituitary stimulation. (author)

Alternative complement pathway and factor B activities in rats with altered blood levels of thyroid hormone

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Bitencourt, C.S. [Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Duarte, C.G.; Azzolini, A.E.C.S.; Assis-Pandochi, A.I. [Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

2012-03-02

Evaluating the activity of the complement system under conditions of altered thyroid hormone levels might help elucidate the role of complement in triggering autoimmune processes. Here, we investigated alternative pathway (AP) activity in male Wistar rats (180 ± 10 g) after altering their thyroid hormone levels by treatment with triiodothyronine (T3), propylthiouracil (PTU) or thyroidectomy. T3 and thyroxine (T4) levels were determined by chemiluminescence assays. Hemolytic assays were performed to evaluate the lytic activity of the AP. Factor B activity was evaluated using factor B-deficient serum. An anti-human factor B antibody was used to measure factor B levels in serum by radial immunodiffusion. T3 measurements in thyroidectomized animals or animals treated with PTU demonstrated a significant reduction in hormone levels compared to control. The results showed a reduction in AP lytic activity in rats treated with increasing amounts of T3 (1, 10, or 50 µg). Factor B activity was also decreased in the sera of hyperthyroid rats treated with 1 to 50 µg T3. Additionally, treating rats with 25 µg T3 significantly increased factor B levels in their sera (P < 0.01). In contrast, increased factor B concentration and activity (32%) were observed in hypothyroid rats. We conclude that alterations in thyroid hormone levels affect the activity of the AP and factor B, which may in turn affect the roles of AP and factor B in antibody production.

Alternative complement pathway and factor B activities in rats with altered blood levels of thyroid hormone

International Nuclear Information System (INIS)

Bitencourt, C.S.; Duarte, C.G.; Azzolini, A.E.C.S.; Assis-Pandochi, A.I.

2012-01-01

Evaluating the activity of the complement system under conditions of altered thyroid hormone levels might help elucidate the role of complement in triggering autoimmune processes. Here, we investigated alternative pathway (AP) activity in male Wistar rats (180 ± 10 g) after altering their thyroid hormone levels by treatment with triiodothyronine (T3), propylthiouracil (PTU) or thyroidectomy. T3 and thyroxine (T4) levels were determined by chemiluminescence assays. Hemolytic assays were performed to evaluate the lytic activity of the AP. Factor B activity was evaluated using factor B-deficient serum. An anti-human factor B antibody was used to measure factor B levels in serum by radial immunodiffusion. T3 measurements in thyroidectomized animals or animals treated with PTU demonstrated a significant reduction in hormone levels compared to control. The results showed a reduction in AP lytic activity in rats treated with increasing amounts of T3 (1, 10, or 50 µg). Factor B activity was also decreased in the sera of hyperthyroid rats treated with 1 to 50 µg T3. Additionally, treating rats with 25 µg T3 significantly increased factor B levels in their sera (P < 0.01). In contrast, increased factor B concentration and activity (32%) were observed in hypothyroid rats. We conclude that alterations in thyroid hormone levels affect the activity of the AP and factor B, which may in turn affect the roles of AP and factor B in antibody production

Fundamental and clinical study for PHT (parathyroid hormone) kit 'Yamasa'

International Nuclear Information System (INIS)

Fukunaga, Masao; Otsuka, Nobuaki; Furukawa, Takako; Morita, Rikushi

1987-01-01

A commercially available radioimmunoassay kit (Yamasa) for parathyroid hormone (PTH) is the midregion-specific assay system. Fundamental study of the PTH kit gave favorable results for specificity, reproducibility, dilution, and recovery. The serum PTH concentration was detectable among all 41 normal volunteers. The upper and lower limits of normal for PTH in serum were found to be 600 pg/ml and 184 pg/ml, respectively. PTH values were high for chronic renal failure (6/7) and primary hyperparathyroidism (41/41), and low for malignancy associated with hypercalcemia (5/25). It seems possible to discriminate hypercalcemic from normal subjects. The serum PTH concentration from the present assay system was significantly correlated with that from conventional carboxyl-terminal PTH, midregion PTH, amino-terminal PTH, and (1 - 84) PTH assay systems. The results indicate the potential of the Yamasa kit in evaluating calcium metabolism, as well as in detecting the presence of secondary hyperparathyroidism. (Namekawa, K.)

[Low levels of TSH measured by a sensitive assay: do they reflect hyperthyroidism? A critical analysis of 580 cases].

Science.gov (United States)

Rohmer, V; Ligeard-Ducoroy, A; Perdrisot, R; Beldent, V; Jallet, P; Bigorgne, J C

1990-05-12

Highly sensitive TSH assays make it easier to diagnose thyroid diseases. During one year, we performed 5,300 sensitive TSH assays (normal range: 0.15-4 mU/l) in various patients. The purpose of this work was to test the value of the low TSH plasma concentrations found in 580 patients. In 99.7 percent of the cases, low TSH levels were the consequence of a thyroid disorder or a treatment by thyroid hormones; non thyroidal illnesses were detected in only 0.3 percent. However, not all TSH values below 0.15 mU/l were associated with overt or occult thyrotoxicosis. When TSH was undetectable (less than 0.04 mU/l), and excluding thyroid hormone-treated patients, thyrotoxicosis was present in 97 percent of the cases. On the other hand, when TSH values were between 0.04 and 0.15 mU/l, 41 percent of the patients failed to show any sign or symptom of hyperthyroidism, although they had functioning thyroid nodules, multinodular goitre or iodine overload, or they received thyroid hormones.

Progress in radiochemical determinations using a radioreagent method in the first half of the 1980's

International Nuclear Information System (INIS)

Kyrs, M.; Moravec, A.

1987-06-01

Procedures published in the period 1980 to 1985 are reviewed and the following topics discussed: separation processes, accuracy and precision, relation to radioimmunoassay and radioreceptor assay, unusual procedures. A brief survey of Shamaev's contributions is given. Typical papers are summarized in a table giving the substance to be determined, radionuclide used, basis and type of the method of determination, accuracy and precision, minimum amount determinable, additional data and references. Conclusions are drawn concerning the development in the pertinent period. (author). 1 fig., 2 tabs., 52 refs

Hormones

Science.gov (United States)

Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work ... glands, which are special groups of cells, make hormones. The major endocrine glands are the pituitary, pineal, ...

Identification of a novel modulator of thyroid hormone receptor-mediated action.

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Bernhard G Baumgartner

Full Text Available BACKGROUND: Diabetes is characterized by reduced thyroid function and altered myogenesis after muscle injury. Here we identify a novel component of thyroid hormone action that is repressed in diabetic rat muscle. METHODOLOGY/PRINCIPAL FINDINGS: We have identified a gene, named DOR, abundantly expressed in insulin-sensitive tissues such as skeletal muscle and heart, whose expression is highly repressed in muscle from obese diabetic rats. DOR expression is up-regulated during muscle differentiation and its loss-of-function has a negative impact on gene expression programmes linked to myogenesis or driven by thyroid hormones. In agreement with this, DOR enhances the transcriptional activity of the thyroid hormone receptor TR(alpha1. This function is driven by the N-terminal part of the protein. Moreover, DOR physically interacts with TR( alpha1 and to T(3-responsive promoters, as shown by ChIP assays. T(3 stimulation also promotes the mobilization of DOR from its localization in nuclear PML bodies, thereby indicating that its nuclear localization and cellular function may be related. CONCLUSIONS/SIGNIFICANCE: Our data indicate that DOR modulates thyroid hormone function and controls myogenesis. DOR expression is down-regulated in skeletal muscle in diabetes. This finding may be of relevance for the alterations in muscle function associated with this disease.

The problem of anti-doping control of luteinizing hormone in boxing.

Science.gov (United States)

Llouquet, Jean Louis; Crepin, Nathalie; Lasne, Françoise

2013-04-01

Luteinizing hormone (LH) is physiologically produced by the anterior pituitary gland. Male athletes may use pharmaceutical LH for doping since it increases the production of testosterone by testes. This hormone is thus on the World Anti-Doping Agency (WADA) list of substances prohibited for males. Anti-doping laboratories perform the assay of this hormone in urine and report abnormally elevated results. We observed a highly significant prevalence of abnormal results in samples taken after a boxing match. Comparison of the descriptive statistics for 426 LH values observed in boxing and other sports showed significant differences. An experimental study comparing urinary LH levels in 17 boxers before and after a match demonstrated a clear increase after the match. The same observation was made for urinary follicle stimulating hormone (FSH) in all of the eight boxers tested for this other pituitary gonadotropin. These observations have consequences for anti-doping controls, as the reference range for urinary LH levels must take into account the specificities of boxers. They also suggest consequences for the health of boxers. Although to our knowledge such observations have never been described, other pituitary disorders have been reported. Our results deserve further investigation from a medical point of view. Copyright © 2013 John Wiley & Sons, Ltd.

Ultrasensitive immunoradiometric assay for chorionic gonadotropin which does not cross-react with luteinizing hormone nor free β chain of hCG and which detects hCG in blood of non-pregnant humans

International Nuclear Information System (INIS)

Griffin, J.; Odell, W.D.

1987-01-01

A sensitive, non-competitive, two-monoclonal antibody, sandwich-type or immunoradiometric assay has been developed for human chorionic gonadotropin (hCG) which shows no cross-reaction with the free β chain of hCG nor with human luteinizing hormone (LH). In the assay procedure, two, highly selected monoclonal antibodies reacted in solution with hCG to be quantified. One antibody was covalently conjugated to biotin. This antibody was specific for the β subunit of hCG, and showed no reaction with LH nor the α subunit. The second antibody was labelled with 125 I and was specific for intact hCG and LH, showing no cross-reaction with βhCG nor the α subunit. The separation system was a polystyrene ball conjugated with biotin. This ball bound via an avidin bridge the monoclonal 'sandwich' containing hCG. Counts per minute bound to the ball were directly proportional to the amount of hCG present. The assay was specific for whole hCG and showed no reaction with βhCG, βLH, intact LH nor the free α subunit. Sensitivity was adequate to detect 'hCG-like' material in all post menopausal women and, when single samples were obtained, in over 2/3 of normal men. When multiple samples were obtained, 'hCG-like' material was detectable in all eugonadal adults studied. 27 refs.; 4 figs.; 1 table

Antiproliferative effect of growth hormone-releasing hormone (GHRH antagonist on ovarian cancer cells through the EGFR-Akt pathway

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Varga Jozsef

2010-05-01

Full Text Available Abstract Background Antagonists of growth hormone-releasing hormone (GHRH are being developed for the treatment of various human cancers. Methods MTT assay was used to test the proliferation of SKOV3 and CaOV3. The splice variant expression of GHRH receptors was examined by RT-PCR. The expression of protein in signal pathway was examined by Western blotting. siRNA was used to block the effect of EGFR. Results In this study, we investigated the effects of a new GHRH antagonist JMR-132, in ovarian cancer cell lines SKOV3 and CaOV3 expressing splice variant (SV1 of GHRH receptors. MTT assay showed that JMR-132 had strong antiproliferative effects on SKOV3 and CaOV3 cells in both a time-dependent and dose-dependent fashion. JMR-132 also induced the activation and increased cleaved caspase3 in a time- and dose-dependent manner in both cell lines. In addition, JMR-132 treatments decreased significantly the epidermal growth factor receptor (EGFR level and the phosphorylation of Akt (p-Akt, suggesting that JMR-132 inhibits the EGFR-Akt pathway in ovarian cancer cells. More importantly, treatment of SKOV3 and CaOV3 cells with 100 nM JMR-132 attenuated proliferation and the antiapoptotic effect induced by EGF in both cell lines. After the knockdown of the expression of EGFR by siRNA, the antiproliferative effect of JMR-132 was abolished in SKOV3 and CaOV3 cells. Conclusions The present study demonstrates that the inhibitory effect of the GHRH antagonist JMR-132 on proliferation is due, in part, to an interference with the EGFR-Akt pathway in ovarian cancer cells.

In vitro conditions modify immunoassayability of bovine pituitary prolactin and growth hormone: insights into their secretory granule storage forms

International Nuclear Information System (INIS)

Lorenson, M.Y.

1985-01-01

The amount of immunoassayable intracellular bovine (b) PRL and GH varies depending on treatment conditions. The present studies were designed to characterize the mechanisms involved and to compare immunoassayability of both hormones under similar conditions. Pituitary homogenate and secretory granule hormones displayed both time- and temperature-dependent increases when incubated at pH 10.5 with reduced glutathione. Changes in immunoassayability seem to reflect conversion from poorly immunoactive tissue hormone oligomers to monomeric hormone. The data indicate that oligomeric bPRL is stabilized primarily by intermolecular disulfide bonds, although it is also susceptible to urea, SDS, and EDTA; granule thiols may also influence the conversion to monomer. The storage form of bGH appears to be stabilized differently. Maneuvers demonstrated in these studies to influence immunoassayability correlate very well with their previously established effects on hormone release and secretion, strengthening the likelihood that a functional link exists between assayability and secretion

The production of high affinity monoclonal antibodies to human growth hormone

International Nuclear Information System (INIS)

Stuart, M.C.; Walichnowski, C.M.; Hussain, S.; Underwood, P.A.; Harman, D.F.; Rathjen, D.A.; Sturmer, S.R. von

1983-01-01

The primary aim of this work was to produce specific monoclonal antibodies to human growth hormone (hGH) for use in a diagnostic RIA of hGH levels in serum. Three different schedules were used for immunization of BALB/c mice and the splenocytes from each mouse were fused with myeloma cells Sp 2/0 Ag 14. Each fusion resulted in the production of hundreds of hybridomas secreting hGH-directed antibodies. Six antibodies have been fully characterized and have been grouped into pairs which recognize 3 different epitopes on the hGH molecule. One pair exhibits no cross reaction with the structurally related placental hormone, human placental lactogen (hPL), a second pair has low cross reaction with hPL (1.6-3%) and a third pair reacts equally well with hGH and hPL indicating binding to a common epitope in the 2 molecules. The highest affinity antibody, 74/6, which has an affinity constant of 4.4x10 10 l/mol and 3% cross-reactivity with hPL, has been used to establish a RIA for serum hGH measurements. Evidence is provided that hGH levels measured in this assay correlate well with those obtained in a conventional rabbit antiserum assay. (Auth.)

Exaggerated gonadotropin response to luteinizing hormone-releasing hormone in amenorrheic runners.

Science.gov (United States)

Yahiro, J; Glass, A R; Fears, W B; Ferguson, E W; Vigersky, R A

1987-03-01

Most studies of exercise-induced amenorrhea have compared amenorrheic athletes (usually runners) with sedentary control subjects. Such comparisons will identify hormonal changes that develop as a result of exercise training but cannot determine which of these changes play a role in causing amenorrhea. To obviate this problem, we assessed reproductive hormone status in a group of five amenorrheic runners and compared them to a group of six eumenorrheic runners matched for body fatness, training intensity, and exercise performance. Compared to the eumenorrheic runners, the amenorrheic runners had lower serum estradiol concentrations, similar basal serum luteinizing hormone and follicle-stimulating hormone concentrations, and exaggerated responses of serum gonadotropins after administration of luteinizing hormone-releasing hormone (100 micrograms intravenous bolus). Serum prolactin levels, both basally and after thyrotropin-releasing hormone administration (500 micrograms intravenous bolus) or treadmill exercise, was similar in the two groups, as were serum thyroid function tests (including thyrotropin response to thyrotropin-releasing hormone). Changes in serum cortisol levels after short-term treadmill exercise were similar in both groups, and serum testosterone levels increased after exercise only in the eumenorrheic group. In neither group did such exercise change serum luteinizing hormone, follicle-stimulating hormone, or thyrotropin levels. We concluded that exercise-induced amenorrhea is not solely related to the development of increased prolactin output after exercise training. The exaggerated gonadotropin response to luteinizing hormone-releasing hormone seen in amenorrheic runners in comparison with matched eumenorrheic runners is consistent with a hypothalamic etiology for the menstrual dysfunction, analogous to that previously described in "stress-induced" or "psychogenic" amenorrhea.

Steroidogenic disruptive effects of the serotonin-noradrenaline reuptake inhibitors duloxetine, venlafaxine and tramadol in the H295R cell assay and in a recombinant CYP17 assay

DEFF Research Database (Denmark)

Islin, Julie; Munkboel, Cecilie Hurup; Styrishave, Bjarne

2018-01-01

The aim of this study was to determine the steroidogenic endocrine disrupting effect of the three most widely used serotonin-noradrenaline reuptake inhibitors duloxetine, venlafaxine and tramadol, using two in vitro models, the H295R assay and a recombinant CYP17 enzyme assay. Steroid hormones were...... quantified using LC-MS/MS. Duloxetine showed endocrine disrupting effects at 5-20μM with CYP17 being the main target. Venlafaxine also affected the steroidogenesis, mainly by affecting the CYP17 lyase reaction, although at much higher concentrations i.e. 100μM. Tramadol only exerted minor effects...... on the steroidogenesis with the lowest observed effect at 314μM. Based on the H295R results, the inhibition of CYP17 by duloxetine and venlafaxine was investigated in a recombinant CYP17 assay with the use of the 4 major CYP17 substrates pregnenolone, progesterone, 17α-hydroxypregnenolone and 17α...

Overnight Levels of Luteinizing Hormone, Follicle-Stimulating Hormone and Growth Hormone before and during Gonadotropin-Releasing Hormone Analogue Treatment in Short Boys Born Small for Gestational Age

NARCIS (Netherlands)

van der Kaay, Danielle C. M.; de Jong, Frank H.; Rose, Susan R.; Odink, Roelof J. H.; Bakker-van Waarde, Willie M.; Sulkers, Eric J.; Hokken-Koelega, Anita C. S.

2009-01-01

Aims: To evaluate if 3 months of gonadotropin-releasing hormone analogue (GnRHa) treatment results in sufficient suppression of pubertal luteinizing hormone (LH) and follicle-stimulating hormone (FSH) profile patterns in short pubertal small for gestational age (SGA) boys. To compare growth hormone

The interrelationships of thyroid and growth hormones: effect of growth hormone releasing hormone in hypo- and hyperthyroid male rats.

Science.gov (United States)

Root, A W; Shulman, D; Root, J; Diamond, F

1986-01-01

Growth hormone (GH) and the thyroid hormones interact in the hypothalamus, pituitary and peripheral tissues. Thyroid hormone exerts a permissive effect upon the anabolic and metabolic effects of GH, and increases pituitary synthesis of this protein hormone. GH depresses the secretion of thyrotropin and the thyroid hormones and increases the peripheral conversion of thyroxine to triiodothyronine. In the adult male rat experimental hypothyroidism produced by ingestion of propylthiouracil depresses the GH secretory response to GH-releasing hormone in vivo and in vitro, reflecting the lowered pituitary stores of GH in the hypothyroid state. Short term administration of large amounts of thyroxine with induction of the hyperthyroid state does not affect the in vivo GH secretory response to GH-releasing hormone in this animal.

Serum protein inhibition of thyrotropin binding to human thyroid tissue

International Nuclear Information System (INIS)

Beall, G.N.; Chopra, I.J.; Solomon, D.H.; Kruger, S.R.

1978-01-01

We used a modificaton of the TSH radioreceptor assay to detect TSH-binding inhibition (TBI) activity in serum and serum fractions from normal subjects and patients with Graves' disease. TBI activity is present in normal IgG prepared by DEAE-Sephadex chromatography and in normal globulins prepared by precipitation at 1.6 M ammonium sulfate. Other normal serum proteins also had TBI activity when large concentrations were tested. Gel filtration chromatography and powder block electrophoresis were used to prepare fractions of normal and Graves' disease sera. In these fractions from normal serum, TBI activity was found in both γ-globulin and α-globulin-albumin fractions electrophoretically and in both 7S and 4S peaks from gel filtration. TBI activity from Graves' disease patients' sera was similarly distributed, but relatively more TBI accompanied the electrophoretic γ-globulins. Sepharose Protein-A and anti-IgG were used as immunoabsorbents to isolate and purify IgG from normal and Graves' disease sera. TBI activity in IgG was proportional to the IgG concentration, indicating that the TBI which migrates as a γ-globulin electrophoretically is an IgG and thus may possibly be an antibody. Inhibitory activity found in normal serum globulins and in the non-IgG fractions of both normal and abnormal sera seriously interferes with attempts to use the TSH radioreceptor assay to study the hypothesized anti-TSH receptor antibody in the serum of patients with Graves' disease

[Changes of the immune cells, cytokines and growth hormone in teenager drug addicts].

Science.gov (United States)

Kuang, Ying-min; Zhu, Yue-chun; Kuang, Ying; Sun, Yuan; Hua, Chen; He, Wen-yi

2007-09-01

To investigate the effect of heroin on the immune function, growth and development in the teenager heroin addicts by measuring their T-lymphocyte subsets, Th1/Th2 cytokines and serum growth hormone. Tlymphocyte subsets of peripheral blood from the teenager heroin addicts were measured by direct microvolume whole blood immunofluorescent staining technique by flow cytometer (FCM). Thl / Th2 cytokines were measured by BD cytometric bead array and serum growth hormone was assayed using the chemiluminescence method in the 20 teenager heroin addicts and 23 healthy teenagers. The levels of CD3(+), CD3(+) + CD4(+), CD3(+) + CD4(+)/CD3(+)+ CD8(+), Th1 cytokines(IL-2, TNF-alpha and IFN-gamma) and Th2 cytokines(IL-4 and IL-10) reduced significantly in the teenager heroin addicts compared with the healthy control group (P teenager heroin addicts was remarkably higher than that in control group (Pteenager heroin addicts. Besides, it can increase the level of serum growth hormone of the teenager heroin addicts.

Response of the pigeon crop sac to mammotrophic hormones: Comparison between relaxin and prolactin

International Nuclear Information System (INIS)

Bani, G.; Sacchi, T.B.; Bigazzi, M.

1990-01-01

The effects of relaxin (RLX), a hormone that has previously been demonstrated to have mammotrophic properties, were studied in the pigeon crop sac, a well-known target organ for mammotrophic and lactogenic hormones, and compared with the effects produced by prolactin (PRL). The two hormones were injected directly over the crop at different doses and the response was evaluated after differing times of exposure. RLX causes a dose-related increase in wet and dry weights and [ 3 H]thymidine and [ 3 H]uridine uptake by the crop mucosa, as well as morphological changes indicating growth and differentiation of the epithelial cells similar to those occurring during physiological activation in incubation and hatching. At the doses assayed, the effects of RLX were nearly identical to those obtained following PRL in the short-term experiments, but differences in functional responses were found in the long-term experiment

Hormonal contraception use alters stress responses and emotional memory.

Science.gov (United States)

Nielsen, Shawn E; Segal, Sabrina K; Worden, Ian V; Yim, Ilona S; Cahill, Larry

2013-02-01

Emotionally arousing material is typically better remembered than neutral material. Since norepinephrine and cortisol interact to modulate emotional memory, sex-related influences on stress responses may be related to sex differences in emotional memory. Two groups of healthy women - one naturally cycling (NC women, n=42) and one using hormonal contraceptives (HC women, n=36) - viewed emotionally arousing and neutral images. Immediately after, they were assigned to Cold Pressor Stress (CPS) or a control procedure. One week later, participants received a surprise free recall test. Saliva samples were collected and later assayed for salivary alpha-amylase (biomarker for norepinephrine) and cortisol. Compared to NC women, HC women exhibited significantly blunted stress hormone responses to the images and CPS. Recall of emotional images differed between HC and NC women depending on noradrenergic and cortisol responses. These findings may have important implications for understanding the neurobiology of emotional memory disorders, especially those that disproportionately affect women. Published by Elsevier B.V.

Thyroid hormone-like and estrogenic activity of hydroxylated PCBs in cell culture

International Nuclear Information System (INIS)

Kitamura, Shigeyuki; Jinno, Norimasa; Suzuki, Tomoharu; Sugihara, Kazumi; Ohta, Shigeru; Kuroki, Hiroaki; Fujimoto, Nariaki

2005-01-01

The thyroid hormone-disrupting activity of hydroxylated PCBs was examined. 4-Hydroxy-2,2',3,4',5,5'-hexachlorobiphenyl (4-OH-2,2',3,4',5,5'-HxCB), 4-hydroxy-3,3',4',5-tetrachlorobiphenyl (4-OH-3,3',4',5-TCB) and 4,4'-dihydroxy-3,3',5,5'-tetrachlorobiphenyl (4,4'-diOH-3,3',5,5'-TCB), which have been detected as metabolites of PCBs in animals and humans, and six other 4-hydroxylated PCBs markedly inhibited the binding of triiodothyronine (1 x 10 -10 M) to thyroid hormone receptor (TR) in the concentration range of 1 x 10 -6 to 1 x 10 -4 M. However, 4-hydroxy-2',4',6'-trichlorobiphenyl (4-OH-2',4',6'-TCB), 3-hydroxy-2,2',5,5'-tetrachlorobiphenyl, 4-hydroxy-2,2',5,5'-tetrachlorobiphenyl, 4-hydroxy-2,3,3',4'-tetrachlorobiphenyl, 2,3',5,5'-tetrachlorobiphenyl and 2,3',4',5,5'-pentachlorodiphenyl did not show affinity for TR. The thyroid hormonal activity of PCBs was also examined using rat pituitary cell line GH3 cells, which grow and release growth hormone in a thyroid hormone-dependent manner. 4-OH-2,2',3,4',5,5'-HxCB, 4,4'-diOH-3,3',5,5'-TCB and 4-OH-3,3',4',5-TCB enhanced the proliferation of GH3 cells and stimulated their production of growth hormone in the concentration range of 1 x 10 -7 to 1 x 10 -4 M, while PCBs which had no affinity for thyroid hormone receptor were inactive. In contrast, only 4-OH-2',4',6'-TCB exhibited a significant estrogenic activity using estrogen-responsive reporter assay in MCF-7 cells. However, the 3,5-dichloro substitution of 4-hydroxylated PCBs markedly decreased the estrogenic activity. These results suggest that, at least for the 17 PCB congeners and hydroxylated metabolites tested, a 4-hydroxyl group in PCBs is essential for thyroid hormonal and estrogenic activities, and that 3,5-dichloro substitution favors thyroid hormonal activity, but not estrogenic activity

Measurement of human serum parathyroid hormone in disorders of calcium metabolism and during administration of certain gut hormones

International Nuclear Information System (INIS)

Coetzee, J.; Klaff, L.J.; Epstein, S.

1980-01-01

A sensitive radio-immunoassay for parathyroid hormone (PTH) using the commercially available antisera AS 211/32 and AS 211/41 has been established. The lower limit of sensitivity of the assay is 0,25 ng/ml. Seventy-nine per cent of normal subjects have PTH levels in the measurable range, with a mean of 0,49 ng/ml (SD more or less 0,26 ng/ml). Only 1 of 9 patients with proven primary hyperparathyroidism had a normal serum PTH value. The mean serum PTH value in this group was 3,0 more or less 0,26 ng/ml, which differed significantly from that in the normal group (P<0,001). The serum PTH level of 33 patients on chronic haemodialysis was uniformly raised, while in 8 patients with hypoparathyroidism PTH levels were undetectable. Patients with malignant disease presented a mixed picture, with raised, normal or undetectable PTH levels. We investigated a possible relationship between the gut hormones, gastrin, secretin and cholecystokininpancreozymin (CCK-PZ) and PTH secretion in human volunteers. No effect was found, although the investigations were conducted over relatively short time periods

Profiles of alpha-melanocyte-stimulating hormone in the Japanese flounder as revealed by a newly developed time-resolved fluoroimmunoassay and immunohistochemistry.

Science.gov (United States)

Amiya, Noriko; Amano, Masafumi; Takahashi, Akiyoshi; Yamanome, Takeshi; Yamamori, Kunio

2007-03-01

Profiles of alpha-melanocyte-stimulating hormone (alpha-MSH) in the Japanese flounder were examined by a newly developed time-resolved fluoroimmunoassay (TR-FIA) and immunohistochemistry. A TR-FIA for alpha-MSH was newly developed, and its levels in the pituitary gland and plasma of Japanese flounder reared in a white or black tank for 5 months were compared. A competitive assay using two antibodies was performed among secondary antibodies in the solid phase, alpha-MSH antibodies, samples, and europium-labeled Des-Ac-alpha-MSH. The sensitivity of the assay, defined as twice the standard deviation at a zero dose, was 0.98 ng/ml (49 pg/well). The intra- and interassay coefficients of variation of the assay were 8.8% (n=8) and 17.3% (n=5), respectively, at about 50% binding. Cross-reactivities of Des-Ac-alpha-MSH and Di-Ac-alpha-MSH were about 100%. Cross-reactivities of adrenocorticotropic hormone, salmon gonadotropin-releasing hormone (sGnRH), and chicken GnRH-II were less than 0.2%, and that of melanin-concentrating hormone was less than 2.0% at 50% binding. Displacement curves of serially twofold-diluted hypothalamus extract, pituitary gland extract, and plasma extract of Japanese flounder with the assay buffer were parallel to the alpha-MSH standard curve. Moreover, displacement curves of serially twofold-diluted hypothalamus and/or pituitary gland extract of masu salmon, goldfish, red seabream, Japanese eel, tiger puffer, and barfin flounder with the assay buffer were also parallel to the alpha-MSH standard. In Japanese flounder, total immunoreactive (ir)-alpha-MSH levels in the pituitary gland were lower in the black tank, whereas those in the plasma tended to be higher in the black tank, suggesting that the synthesis and release of alpha-MSH are higher in the black tank. alpha-MSH-ir cells were detected in the pars intermedia and a small part of the pars distalis of the pituitary gland. alpha-MSH-ir cell bodies were located in the basal hypothalamus and alpha

Interconnection between thyroid hormone signalling pathways and parvovirus cytotoxic functions.

OpenAIRE

Vanacker, J M; Laudet, V; Adelmant, G; Stéhelin, D; Rommelaere, J

1993-01-01

Nonstructural (NS) proteins of autonomous parvoviruses can repress expression driven by heterologous promoters, an activity which thus far has not been separated from their cytotoxic effects. It is shown here that, in transient transfection assays, the NS-1 protein of the parvovirus minute virus of mice (MVMp) activates the promoter of the human c-erbA1 gene, encoding the thyroid hormone (T3) receptor alpha. The endogenous c-erbA1 promoter is also a target for induction upon MVMp infection. M...

Circulating 25-hydroxy vitamin D correlates with serum level of anti-Müllerian hormone in male patients with chronic kidney disease.

Science.gov (United States)

Abdel Hamid, F F; Soliman, A F; Lashin, F E S

2018-02-14

This study was designed to assess the relationship between serum levels of anti-Müllerian hormone and 25-hydroxy vitamin D in chronic kidney disease male patients. For that, serum 25-hydroxy vitamin D and anti-Müllerian hormone along with follicle-stimulating hormone, luteinising hormone, prolactin, total testosterone and estradiol were assayed in 59 patients with different stages of chronic kidney disease and 21 healthy participants. Compared to controls, serum levels of anti-Müllerian hormone and 25-hydroxy vitamin D were significantly decreased in patients with chronic kidney disease. The decreased anti-Müllerian hormone level correlated positively with estimated glomerular filtration rate and serum levels of testosterone and 25-hydroxy vitamin D. Meanwhile, it was negatively correlated with age and serum levels of urea, creatinine, follicle-stimulating hormone, luteinising hormone and prolactin. 25-Hydroxy vitamin D and luteinising hormone explained the 65.9% variability of anti-Müllerian hormone in a multiple linear regression model. However, anti-Müllerian hormone in crude correlation was more strongly associated with serum 25-hydroxy vitamin D than luteinising hormone. In conclusion, serum level of 25-hydroxy vitamin D might be a determinant factor of anti-Müllerian hormone level, and their relationship might explain in part the dysfunction of Sertoli cells and the impaired testicular functions in chronic kidney disease male patients. © 2018 Blackwell Verlag GmbH.

Quality control of radioimmunoassay kits of pituitary hormones

International Nuclear Information System (INIS)

Caso Pena, R.; Arranz Calzado, C.

1997-01-01

The present work describe the quality control procedures carried out on three RIA-Kits by the Isotopes Centre of Cuba, The subject matter of study were ;: were: LH-RIA-Kit, FSH-RIA-Kit and Prolactin- RIA -Kit. The controls have included the characterization of the 125 I labelled hormones the specific antibodies, the 2 nd antibodies, the standards curves and the control serum. For the validation of these Kits were used reference standards from the WHO (World Health Organizations) and Kits from CIS company (France) based on the IRMA assays technologies . The results obtained allow us encourage the reliability of RIA-Kits

Characterization of monoclonal antibodies directed against human thyroid stimulating hormone

International Nuclear Information System (INIS)

Soos, M.; Siddle, K.

1982-01-01

Monoclonal antibodies directed against human thyroid stimulating hormone (TSH) were obtained from hybrid myelomas, following fusion of mouse NSI myeloma cells with mouse spleen cells. Ten different antibodies were obtained from 4 separate fusions. Eight antibodies were of the IgG 1 subclass. Affinities of antibodies for TSH were in the range 2 x 10 8 -5 x 10 10 M -1 . Five of the antibodies were specific for TSH and did not react with LH, FSH or hCG. The remaining antibodies reacted with all these hormones and were assumed to recognise their common (α) subunit. The 5 specific antibodies fell into 3 subgroups recognising distinct antigenic determinants, whereas the 5 non-specific antibodies recognised a single determinant or closely related set of sites. It is concluded that these antibodies should be valuable reagents for use in sensitive and specific two-site immunoradiometric assays. (Auth.)

Development of statistical and analytical techniques for use in national quality control schemes for steroid hormones

International Nuclear Information System (INIS)

Wilson, D.W.; Gaskell, S.J.; Fahmy, D.R.; Joyce, B.G.; Groom, G.V.; Griffiths, K.; Kemp, K.W.; Nix, A.B.J.; Rowlands, R.J.

1979-01-01

Adopting the rationale that the improvement of intra-laboratory performance of immunometric assays will enable the assessment of national QC schemes to become more meaningful, the group of participating laboratories has developed statistical and analytical techniques for the improvement of accuracy, precision and monitoring of error for the determination of steroid hormones. These developments are now described and their relevance to NQC schemes discussed. Attention has been focussed on some of the factors necessary for improving standards of quality in immunometric assays and their relevance to laboratories participating in NQC schemes as described. These have included the 'accuracy', precision and robustness of assay procedures as well as improved methods for internal quality control. (Auth.)

Juvenile hormone-binding proteins of Melanoplus bivittatus identified by EFDA photoaffinity labeling

International Nuclear Information System (INIS)

Winder, B.S.

1988-01-01

Proteins that bind juvenile hormone in the hemolymph and fat body of the grasshopper, Melanoplus bivittatus were identified by photoaffinity labeling with radiolabeled epoxyfarnesyl diazoacetate ( 3 H-EFDA), and were characterized by electrophoretic analysis. A protocol was developed which allowed detection of 3 H-EFDA that was covalently linked to proteins upon exposure to ultraviolet light at 254 nm. Quantification of protein-linked 3 H-EFDA by liquid scintillation spectrometry took advantage of the differential solubility of unlinked 3 H-EFDA in toluene alone, and of the protein-linked 3 H-EFDA in toluene plus the detergent, Triton X-100. Competition between EFDA and juvenile hormone (JH) for binding to JH-specific binding sites was measured by hydroxyapatite protein binding assays in the presence of radiolabeled JH or EFDA and competing non-radiolabeled hormone. The protein-linked EFDA was detected on fluorograms of SDS or nondenaturing polyacrylamide gels (PAGE), and by liquid scintillation spectrometry of membranes to which the proteins had been electrophoretically transferred. Proteins which specifically bound JH were identified by photolabeling proteins in the presence and absence of nonlabeled JH-III

New fluorimetric assay of horseradish peroxidase using sesamol as substrate and its application to EIA.

Science.gov (United States)

Arakawa, Hidetoshi; Nakabayashi, Shigeo; Ohno, Ken-Ichi; Maeda, Masako

2012-04-01

Horseradish peroxidase (HRP) is generally used as a label enzyme in enzyme immunoassay (EIA). The procedure used for HRP detection in EIA is critical for sensitivity and precision. This paper describes a novel fluorimetric assay for horseradish peroxidase (HRP) using sesamol as substrate. The principle of the assay is as follow: sesamol (3,4-methylenedioxy phenol) is reacted enzymatically in the presence of hydrogen peroxide to produce dimeric sesamol. The dimer is fluorescent and can be detected sensitively at ex. 347 nm, em. 427 nm. The measurable range of HRP was 1.0×10 -18 to 1.0×10 -15  mol/assay, with a detection limit of 1.0×10 -18  mol/assay. The coefficient of variation (CV, n =8) was examined at each point on the standard curve, with a mean CV percentage of 3.8%. This assay system was applied to thyroid stimulating hormone (TSH) EIA using HRP as the label enzyme.

Effect of growth hormone replacement therapy on pituitary hormone secretion and hormone replacement therapies in GHD adults

DEFF Research Database (Denmark)

Hubina, Erika; Mersebach, Henriette; Rasmussen, Ase Krogh

2004-01-01

We tested the impact of commencement of GH replacement therapy in GH-deficient (GHD) adults on the circulating levels of other anterior pituitary and peripheral hormones and the need for re-evaluation of other hormone replacement therapies, especially the need for dose changes.......We tested the impact of commencement of GH replacement therapy in GH-deficient (GHD) adults on the circulating levels of other anterior pituitary and peripheral hormones and the need for re-evaluation of other hormone replacement therapies, especially the need for dose changes....

Expression of IGF-I and Protein Degradation Markers During Hindlimb Unloading and Growth Hormone Administration in Rats

Science.gov (United States)

Leinsoo, T. A.; Turtikova, O. V.; Shenkman, B. S.

2013-02-01

It is known that hindlimb unloading or spaceflight produce atrophy and a number of phenotypic alterations in skeletal muscles. Many of these processes are triggered by the axis growth hormone/insulin-like growth factor I. However growth hormone (GH) and insulin-like growth factor I (IGF-I) expression relationship in rodent models of gravitational unloading is weakly investigated. We supposed the IGF-I is involved in regulation of protein turnover. In this study we examined the IGF-I expression by RT-PCR assay in the rat soleus, tibialis anterior and liver after 3 day of hindlimb suspension with growth hormone administration. Simultaneously were studied expression levels of MuRF-1 and MAFbx/atrogin as a key markers of intracellular proteolysis. We demonstrated that GH administration did not prevent IGF-I expression decreasing under the conditions of simulated weightlessness. It was concluded there are separate mechanisms of action of GH and IGF-I on protein metabolism in skeletal muscles. Gravitational unloading activate proteolysis independently of growth hormone activity.

Prospective hormone study of hypothalamic-pituitary function in patients with nasopharyngeal carcinoma after high dose irradiation

International Nuclear Information System (INIS)

Chen, Ming-Shen; Lin, Fang-Jen; Huang, Miau-Ju; Wang, Pei-Wan; Tang, Simon; Leung, Wei-Man; Leung, Wan

1989-01-01

With the aim of evaluating the effect of high dose irradiation (6,500 cGy/36 fractions or higher) to pituitary fossa, a prospective study was carried out in patients with nasopharyngeal cancer by a serial determination of several hormones in the serum, before and after the course of radiation therapy (RT). The radiation treatment field was at least 1 cm above the skull base with bilateral parallel opposing fields. Hormone assays were performed three times on each patient: (1)prior to, (2)one month after, (3)15-18 months after radiation therapy. The study included determination of serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroid-stimulating hormone (TSH), cortisol, growth hormone (GH) and prolactin concentrations and LH-releasing hormone, thyrotrophin-releasing hormone stimulation and insulin tolerance tests were also carried out. Complete profiles were obtained in 24 patients (16 males and 8 females), aged 16-67 years. The results showed a significant decrease in the level of serum peak value of LH in males 18 months after therapy, and also in GH both one month and 18 months after therapy. A significant increase in the peak value of serum TSH was observed after therapy. Decreased serum FSH, cortisol and prolactin levels were noted, but these did not reach statistical significance. The decrease in GH level appeared earlier and was more sensitive than that found for the other hormones, and could prove to be a useful parameter for clinical evaluation. None of the patients showed any clinically recognizable symptoms or signs of hormone deficiency in the 18-33 months following completion of the radiation therapy. (author)

Bioidentical Hormones and Menopause

Science.gov (United States)

... Endocrinologist Search Featured Resource Menopause Map™ View Bioidentical Hormones January 2012 Download PDFs English Espanol Editors Howard ... take HT for symptom relief. What are bioidentical hormones? Bioidentical hormones are identical to the hormones that ...

Thyroid and Cortisol hormones in Attention Deficit Hyperactivity Disorder: A case-control study.

Science.gov (United States)

Kuppili, Pooja Patnaik; Pattanayak, Raman Deep; Sagar, Rajesh; Mehta, Manju; Vivekanandhan, S

2017-08-01

There is paucity of research in the putative role of hormonal biomarkers in Attention Deficit Hyperactivity Disorder (ADHD). The current study aimed to analyze the clinical profile, socio-demographic status, co-morbidity, hormonal biomarkers namely Thyroid hormones and Cortisol in children with ADHD and compare them with healthy controls and to explore the association of the hormonal biomarkers with severity of ADHD. Thirty children with DSM-IV TR diagnosis of ADHD were assessed using semi structured proforma, Conners' Parent Rating Scale revised short (CPRS - R: S) , Mini international neuropsychiatric interview for children and adolescents and Childrens' Global Assessment Scale as well as serum levels of total Triiodothyronine (T3) ,total Thyroxine (T4) , Thyroid Stimulating Hormone (TSH) and Cortisol using chemiluminescent immunometric assay and compared with 30 age- and gender -matched controls. The typical profile of cases of ADHD was of a male with mean age of 9.47 years (S.D=2.43) belonging to Hyperactive subtype of ADHD. Serum T4 was significantly lower in cases compared to controls. No significant difference was found in serum T3, TSH and Cortisol levels. No significant correlation between the CPRS : R-S scores and the hormonal biomarkers. There is need for exploration of Serum T4 as putative biomarker for ADHD with replication in future studies. It may also be important to report the negative finding of Cortisol as a biomarker of ADHD in the context of effective utilization of resources for research with special relevance to resource deficit developing countries. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of congenital hypothyroidism in neonatal by immunoradiometric assays of thyrotropin

International Nuclear Information System (INIS)

Contreras P, E.

1998-01-01

The congenital hypothyroidism is the endocrine illness more frequent of the childhood, it is the one that produce the devastating effects on the growth and the development. It represent one of the few causes of mental delay that it could be prevented if it is diagnosed and treaty on time. The infants affected with congenital hypothyroidism, could be detected for the apparent presence of some physical abnormalities, which comes the first days of the birth. Unfortunately, in the moment in which the classical manifestations are made present, it is very probable that cerebral damage already exists, for what the affected children should be tried before the three months of life administering them thyroid hormones. In Mexico the incidence of the congenital hypothyroidism is of one for each 1612 births for that is very important in the area of Public Health diagnose in early form and with certainty the congenital hypothyroidism. The TSH hormone or thyrotropin is formed in the hypophysis and intervenes in the synthesis of the thyroid hormones (T3, T4) when the concentration of these is adapted, the formation of TSH is inhibited, for that upon lacking the thyroid hormones the concentration of TSH in the blood is high. For these reasons the shot metabolic state of a newborn could be determined, quantifying the TSH in blood obtained by heel stab of the neonatal, or in coming blood from the umbilical cord, after 48 hours of being born. However because the TSH is similar to other hormones and is in extremely low concentrations, it is made necessary appeal analytic techniques of very sensitive and specific laboratory like the Immunoradiometric assays (Irma) in order to could determine the levels of this hormone in the blood. (Author)

Application of ovine luteinizing hormone (LH) radioimmunoassay in the quantitation of LH in different mammalian species

International Nuclear Information System (INIS)

Millar, R.P.; Aehnelt, C.

1977-01-01

A sensitive double antibody radioimmunoassay has been developed for measuring luteinizing hormone (LH) in various African mammalian species, using rabbit anti-ovine LH serum (GDN 15) and radioiodinated rat LH or ovine LH. Serum and pituitary homogenates from some African mammals (hyrax, reedbuck, sable, impala, tsessebe, thar, spring-hare, ground squirrel and cheetah, as well as the domestic sheep, cow and horse and laboratory rat and hamster) produced displacement curves parallel to that of the ovine LH standards. The specificity of the assay was examined in detail for one species, the rock hyrax. Radioimmunoassay and bioassay estimates of LH in hyrax pituitaries containing widely differing quantities of pituitary hormones were similar. In sexually active male hyrax mean plasma LH was 12.1 ng/ml and pituitary LH 194 μg/gland, but in sexually quiescent hyrax mean plasma LH was 2.4 ng/ml and mean pituitary LH 76 μg/gland. Intravenous injection of 10 μg of luteinizing hormone releasing hormone increased mean LH levels in hyrax from 0.9 ng/ml to 23.2 ng/ml by 30 min. Conversely, im injection of 250 μg testosterone induced a fall in LH levels in male hyrax from 1.7 ng/ml to 0.7 ng/ml 6 h after administration. Although the specificity of the assay for quantitating plasma LH in other species was not categorically established, there was a good correlation between plasma LH concentration and reproductive state in the bontebok, impala, spring-hare, thar, cheetah, domestic horse and laboratory rat, suggesting the potential use of the antiserum in quantitating LH in a variety of mammalian species

Serum level of hormone and metabolites in pregnant rabbit does

Directory of Open Access Journals (Sweden)

Gabriele Brecchia

2010-01-01

Full Text Available The aims of this study were to compare the hormones and metabolites serum levels and the reproductive performances of nulliparous (n=100 and primiparous pregnant does submitted to artificial insemination (AI 11 days post-partum. On the day of AI, all the does were weighed and the sexual receptivity was evaluated. The kits were weaned at 26 day. Blood samples were collect by punc- ture of the marginal ear vein from one day before AI until few days before the kindling and assayed for hormones and metabolites. The higher sexual receptivity and the fertility in nulliparous than in primiparous does confirmed the negative effect of lactation. Nulliparous does showed higher blood con- centration of leptine than primiparous, and in both the groups such level lowered during pregnancy, probably reflecting the reduction of the fat reserve. The insuline level increased during pregnancy in either groups as a consequence of the growing of the foetuses. In nulliparous does the cortisol, NEFA and T3 concentrations were higher than primiparous does. The glucose levels were similar in both the groups probably due to the homeostatic mechanisms controlling the glycemia. Hormonal and metabo- lite analyses represent a good tool for understanding the physiological mechanisms required to meet higher reproductive performance.

Immunochemical and immunocytochemical studies of the crustacean vitellogenesis-inhibiting hormone (VIH).

Science.gov (United States)

Meusy, J J; Martin, G; Soyez, D; van Deijnen, J E; Gallo, J M

1987-09-01

Immunochemical investigations, using dot immunobinding assay (DIA) and enzyme-linked immunosorbent assay (ELISA), and immunocytochemical studies reveal the following new information about crustacean vitellogenesis-inhibiting hormone (VIH): (1) The structure of VIH is sufficiently different from that of the other sinus gland neuropeptides to allow a selective recognition of VIH by polyclonal antibodies. (2) From immunochemical criteria, VIH does not seem strictly species specific. The antisera raised against VIH of Homarus americanus cross-react with sinus gland extracts of Palaemonetes varians, Palaemon serratus, Macrobrachium rosenbergii, Carcinus maenas, and Porcellio dilatatus. (3) In the sinus gland of H. americanus, VIH immunoreactivity is localized mainly in electron-dense granules of medium size (110-185 nm in diameter) while, in P. dilatatus, the labeling is mostly on the largest granules (200-270 nm in diameter).

Hormones and absence epilepsy

NARCIS (Netherlands)

Luijtelaar, E.L.J.M. van; Tolmacheva, E.A.; Budziszewska, B.; Stein, J.

2017-01-01

Hormones have an extremely large impact on seizures and epilepsy. Stress and stress hormones are known to reinforce seizure expression, and gonadal hormones affect the number of seizures and even the seizure type. Moreover, hormonal concentrations change drastically over an individual's lifetime,

Lepidium meyenii (Maca) enhances the serum levels of luteinising hormone in female rats.

Science.gov (United States)

Uchiyama, Fumiaki; Jikyo, Tamaki; Takeda, Ryosuke; Ogata, Misato

2014-02-03

Lepidium meyenii (Maca) is traditionally employed in the Andean region for its supposed fertility benefits. This study investigated the effect of Maca on the serum pituitary hormone levels during the pro-oestrus phase. Maca powder was made from the tubers of Lepidium meyenii Walp collected, dried, and reduced to powder at the plantation in Junín Plateau and was purchased from Yamano del Perú SAC. The Maca powder was identified by chemical profiling and taxonomic methods. Two groups of female Sprague-Dawley rats were provided feed with normal feed containing 5%, 25%, or 50% Maca powder ad libitum for 7 weeks. At 1800h of the proestrus stage, the rats were euthanised, and blood samples were collected for serum isolation. The serum pituitary hormone levels were measured using enzyme-linked immunosorbent assays (ELISAs). No significant differences in feed intake or growth rate were observed among the rats. During the pro-oestrus stage, a 4.5-fold increase (PMaca powder compared with the control rats. No significant differences were observed in the levels of the other pituitary hormones, including growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH), and thyroid-stimulating hormone (TSH). A dose-dependent increase of LH serum levels was observed within the range of 3-30g Maca/kg. Furthermore, the enhancement of the LH serum levels was specific to the pro-oestrus LH surge. The present study demonstrates that Maca uniquely enhances the LH serum levels of pituitary hormones in female rats during the pro-oestrus LH surge and acts in a pharmacological, dose-dependent manner. These findings support the traditional use of Maca to enhance fertility and suggest a potential molecular mechanism responsible for its effects. © 2013 Elsevier Ireland Ltd. All rights reserved.

[Serum hormones that regulate the reproductive axis in men with testicular germ cell cancer and its impact on fertility].

Science.gov (United States)

Tovar-Rodríguez, José María; Chávez-Zúñiga, Irma; Bañuelos-Ávila, Leticia; Vargas-Hernández, Víctor Manuel; Acosta-Altamirano, Gustavo

2014-01-01

Epidemiological studies treat testicular germ cancer as a single disease, the behavior of the two histological types of cancer; seminoma and nonseminoma have differences in reproductive hormone secretion and impair fertility differently. To demonstrate that the serum concentration of pituitary hormones involved in fertility and spermatogenesis in the affected male is different in the two histological types. Were determined by radioimmunoassay or inmunoradiometric assay, luteinizing hormone, follicle stimulating hormone, total testosterone, prolactin, estradiol, human chorionic gonadotropin and alpha fetoprotein in 37 patients with germ cell cancer (15 seminoma and 22 nonseminoma) and 35 controls. We analyzed the semen of patients, and were questioned about paternity before the cancer diagnosis. Age was higher in patients with seminoma cancer, showed decreased luteinizing hormone, follicle stimulating hormone, and testosterone and increased estradiol and prolactin in nonseminoma compared with seminoma. In patients with nonseminoma they had 9 children, 5 were oligozoospermic, 3 azoospermic and 6 normal concentration, 8 did not provide sample, seminoma group they had eight children, only one azoospermic, nine normal concentration, and 5 did not provide sample . The hormonal behavior is different in men with nonseminoma compared with seminoma, so that the negative impact on the reproductive axis and fertility is higher in cases of non-seminoma.

Impact of Drinking Water Fluoride on Human Thyroid Hormones: A Case- Control Study.

Science.gov (United States)

Kheradpisheh, Zohreh; Mirzaei, Masoud; Mahvi, Amir Hossein; Mokhtari, Mehdi; Azizi, Reyhane; Fallahzadeh, Hossein; Ehrampoush, Mohammad Hassan

2018-02-08

The elevated fluoride from drinking water impacts on T 3 , T 4 and TSH hormones. The aim was study impacts of drinking water fluoride on T 3 , T 4 and TSH hormones inYGA (Yazd Greater Area). In this case- control study 198 cases and 213 controls were selected. Fluoride was determined by the SPADNS Colorimetric Method. T 3 , T 4 and TSH hormones tested in the Yazd central laboratory by RIA (Radio Immuno Assay) method. The average amount of TSH and T 3 hormones based on the levels of fluoride in two concentration levels 0-0.29 and 0.3-0.5 (mg/L) was statistically significant (P = 0.001 for controls and P = 0.001 for cases). In multivariate regression logistic analysis, independent variable associated with Hypothyroidism were: gender (odds ratio: 2.5, CI 95%: 1.6-3.9), family history of thyroid disease (odds ratio: 2.7, CI 95%: 1.6-4.6), exercise (odds ratio: 5.34, CI 95%: 3.2-9), Diabetes (odds ratio: 3.7, CI 95%: 1.7-8), Hypertension (odds ratio: 3.2, CI 95%: 1.3-8.2), water consumption (odds ratio: 4, CI 95%: 1.2-14). It was found that fluoride has impacts on TSH, T 3 hormones even in the standard concentration of less than 0.5 mg/L. Application of standard household water purification devices was recommended for hypothyroidism.

Evidence for a synchronization of hormonal states between humans and dogs during competition.

Science.gov (United States)

Buttner, Alicia Phillips; Thompson, Breanna; Strasser, Rosemary; Santo, Jonathan

2015-08-01

Social interactions with humans have been shown to influence hormonal processes in dogs, but it is unclear how the hormonal states of humans factor into this relationship. In this study, we explored the associations between changes in the cortisol levels of dogs with humans' hormonal changes, behavior, and perceptions of their performance at an agility competition. A total of 58 dogs and their handlers (44 women, 14 men) provided saliva samples before and after competing. Dogs' saliva samples were later assayed for cortisol and humans' samples for cortisol and testosterone. Following the competition, handler-dog interactions were observed for affiliative and punitive behavior towards their dogs, and handlers completed questionnaires that included personal ratings of their performance. Structural equation modeling revealed that elevations in handlers' cortisol levels were associated with increases in their dogs' cortisol levels. Handlers' affiliative and punitive behaviors towards their dogs following competition were associated with their ratings of their performance, but these variables were unrelated to changes in their own cortisol levels and their dogs', implying their behavior did not mediate the relationship. These findings suggest that changes in the hormonal states were reflected between humans and their dogs, and this relationship was not due to handlers' perceptions of their performance or the behaviors we observed during post-competition social interactions. This study is one of the first to provide evidence for a synchronization of hormonal changes between species. Copyright © 2015 Elsevier Inc. All rights reserved.

Negative regulation of parathyroid hormone-related protein expression by steroid hormones

International Nuclear Information System (INIS)

Kajitani, Takashi; Tamamori-Adachi, Mimi; Okinaga, Hiroko; Chikamori, Minoru; Iizuka, Masayoshi; Okazaki, Tomoki

2011-01-01

Highlights: → Steroid hormones repress expression of PTHrP in the cell lines where the corresponding nuclear receptors are expressed. → Nuclear receptors are required for suppression of PTHrP expression by steroid hormones, except for androgen receptor. → Androgen-induced suppression of PTHrP expression appears to be mediated by estrogen receptor. -- Abstract: Elevated parathyroid hormone-related protein (PTHrP) is responsible for humoral hypercalcemia of malignancy (HHM), which is of clinical significance in treatment of terminal patients with malignancies. Steroid hormones were known to cause suppression of PTHrP expression. However, detailed studies linking multiple steroid hormones to PTHrP expression are lacking. Here we studied PTHrP expression in response to steroid hormones in four cell lines with excessive PTHrP production. Our study established that steroid hormones negatively regulate PTHrP expression. Vitamin D receptor, estrogen receptor α, glucocorticoid receptor, and progesterone receptor, were required for repression of PTHrP expression by the cognate ligands. A notable exception was the androgen receptor, which was dispensable for suppression of PTHrP expression in androgen-treated cells. We propose a pathway(s) involving nuclear receptors to suppress PTHrP expression.

Two-step versus one-step FT4 assays in heparin treated patients and non-thyroidal illness

International Nuclear Information System (INIS)

Reiners, C.; Bieler, G.; Ertl, G.; Gloss, H.; Boerner, W.

1985-01-01

The primary intention of this study is to inform the clinician about the direction and the order of magnitude of possible disturbances of different FT 4 parameters under the condition mentioned last, which is not uncommon in daily routine. No single FT 4 -RIA proved be valid in severe NTI. There is the risk to misinterprete hyperthyroidism as euthyroidism with 1step assays and the possibility to classify euthyroid patients falsely as hyperthyroid with 2step assays. In relation to this problem, the sometimes lowered FT 4 values by 1step methods are clinically not so important. It has to be established, wether TSH assays of high sensitivity are able to overcome some of the difficulties with determinations of peripheral thyroid hormones in NTI. (orig./MG)

Effect of race, gender and age on thyroid and thyroid stimulating hormone levels in north west frontier province, Pakistan

International Nuclear Information System (INIS)

Ahmed, Z.; Khan, M.A.; Haq, A.U.

2009-01-01

Thyroid is one of the ductless endocrine gland, which is located immediately below the larynx on either side of and anterior to the trachea. The principal hormones of thyroid gland are thyroxine (T4) and triiodothyronine (T3). The current study was carried out to investigate the impact of race, gender and area on the levels of Thyroxine (T4), Triiodothyronine (T3) and Thyroid Stimulating Hormone (TSH) in normal healthy individuals. Methods: Serum levels of T4, T3 and TSH in 498 normal healthy individuals belonging to different districts of North West Frontier Province, Pakistan, were examined. Serum T4 and T3 were analysed by Radio Immuno Assay (RIA) method whereas TSH was estimated by Immunoradiometric assay (IRMA) method. Results: Levels of T4, T3 and TSH ranged from 53 to 167 m mu mol/L and 0.3-4.8 mu mol/L respectively. The levels of these hormones show significant change from the reference values that are used in clinical laboratories as well as in Institute of Rauclear Medicine (IRNUM), Peshawar, Pakistan. Conclusion: It is concluded that the age, gender, race and area, all have an appreciable effect on the levels T4, T3 and TSH. (author)

Efficacy of chemotherapy after hormone therapy for hormone receptor-positive metastatic breast cancer.

Science.gov (United States)

Mori, Ryutaro; Nagao, Yasuko

2014-01-01

According to the guidelines for metastatic breast cancer, hormone therapy for hormone receptor-positive metastatic breast cancer without life-threatening metastasis should be received prior to chemotherapy. Previous trials have investigated the sensitivity of chemotherapy for preoperative breast cancer based on the efficacy of neoadjuvant hormone therapy. In this retrospective study, we investigated the efficacy of chemotherapy for metastatic breast cancer in hormone therapy-effective and hormone therapy-ineffective cases. Patients who received chemotherapy after hormone therapy for metastatic breast cancer between 2006 and 2013 at our institution were investigated. A total of 32 patients received chemotherapy after hormone therapy for metastatic breast cancer. The median patient age was 59 years, and most of the primary tumors exhibited a T2 status. A total of 26 patients had an N(+) status, while 7 patients had human epidermal growth factor receptor 2-positive tumors. A total of 13 patients received clinical benefits from hormone therapy, with a rate of clinical benefit of subsequent chemotherapy of 30.8%, which was not significantly different from that observed in the hormone therapy-ineffective patients (52.6%). A total of 13 patients were able to continue the hormone therapy for more than 1 year, with a rate of clinical benefit of chemotherapy of 38.5%, which was not significantly different from that observed in the short-term hormone therapy patients (47.4%). The luminal A patients were able to continue hormone therapy for a significantly longer period than the non-luminal A patients (median survival time: 17.8 months vs 6.35 months, p = 0.0085). However, there were no significant differences in the response to or duration of chemotherapy. The efficacy of chemotherapy for metastatic breast cancer cannot be predicted based on the efficacy of prior hormone therapy or tumor subtype, and clinicians should administer chemotherapy in all cases of

A multi-assay screening approach for assessment of endocrine-active contaminants in wastewater effluent samples

Energy Technology Data Exchange (ETDEWEB)

Metcalfe, Chris D., E-mail: cmetcalfe@trentu.ca [Environmental and Resource Studies, Trent University, Peterborough, ON, K9J 7B8 (Canada); Kleywegt, Sonya [Standards Development Branch, Ontario Ministry of the Environment, 40 St. Clair Ave. West, Toronto, ON, M4V 1M2 (Canada); Letcher, Robert J. [Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON, K1A 0H3 (Canada); Topp, Edward [Agriculture and Agri-Food Canada, Southern Crop Protection and Food Research Centre, London, ON, N5V 7T3 (Canada); Wagh, Purva; Trudeau, Vance L.; Moon, Thomas W. [Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada)

2013-06-01

Environmental agencies must monitor an ever increasing range of contaminants of emerging concern, including endocrine disrupting compounds (EDCs). An alternative to using ultra-trace chemical analysis of samples for EDCs is to test for biological activity using in vitro screening assays, then use these assay results to direct analytical chemistry approaches. In this study, we used both analytical approaches and in vitro bioassays to characterize the EDCs present in treated wastewater from four wastewater treatment plants (WWTPs) in Ontario, Canada. Estrogen-mediated activity was assessed using a yeast estrogenicity screening (YES) assay. An in vitro competitive binding assay was used to assess capacity to interfere with binding of the thyroid hormone, thyroxine (T4) to the recombinant human thyroid hormone transport protein, transthyretin (i.e. hTTR). An in vitro binding assay with a rat peroxisome proliferator responsive element transfected into a rainbow trout gill cell line was used to evaluate binding and subsequent gene expression via the peroxisome proliferator activated receptor (PPAR). Analyses of a suite of contaminants known to be EDCs in extracts from treated wastewater were conducted using either gas chromatography with mass spectrometry (GC-MS) or liquid chromatography with tandem mass spectrometry (LC-MS/MS). Estrogenic activity was detected in the YES assay only in those extracts that contained detectable amounts of estradiol (E2). There was a positive relationship between the degree of response in the T4-hTTR assay and the amounts of polybrominated diphenyl ether (PBDE) congeners 47 and 99, triclosan and the PBDE metabolite, 4-OH-BDE17. Several wastewater extracts gave a positive response in the PPAR assay, but these responses were not correlated with the amounts of any of the EDCs analyzed by LC-MS/MS. Overall, these data indicate that a step-wise approach is feasible using a combination of in vitro testing and instrumental analysis to monitor for

A multi-assay screening approach for assessment of endocrine-active contaminants in wastewater effluent samples

International Nuclear Information System (INIS)

Metcalfe, Chris D.; Kleywegt, Sonya; Letcher, Robert J.; Topp, Edward; Wagh, Purva; Trudeau, Vance L.; Moon, Thomas W.

2013-01-01

Environmental agencies must monitor an ever increasing range of contaminants of emerging concern, including endocrine disrupting compounds (EDCs). An alternative to using ultra-trace chemical analysis of samples for EDCs is to test for biological activity using in vitro screening assays, then use these assay results to direct analytical chemistry approaches. In this study, we used both analytical approaches and in vitro bioassays to characterize the EDCs present in treated wastewater from four wastewater treatment plants (WWTPs) in Ontario, Canada. Estrogen-mediated activity was assessed using a yeast estrogenicity screening (YES) assay. An in vitro competitive binding assay was used to assess capacity to interfere with binding of the thyroid hormone, thyroxine (T4) to the recombinant human thyroid hormone transport protein, transthyretin (i.e. hTTR). An in vitro binding assay with a rat peroxisome proliferator responsive element transfected into a rainbow trout gill cell line was used to evaluate binding and subsequent gene expression via the peroxisome proliferator activated receptor (PPAR). Analyses of a suite of contaminants known to be EDCs in extracts from treated wastewater were conducted using either gas chromatography with mass spectrometry (GC-MS) or liquid chromatography with tandem mass spectrometry (LC-MS/MS). Estrogenic activity was detected in the YES assay only in those extracts that contained detectable amounts of estradiol (E2). There was a positive relationship between the degree of response in the T4-hTTR assay and the amounts of polybrominated diphenyl ether (PBDE) congeners 47 and 99, triclosan and the PBDE metabolite, 4-OH-BDE17. Several wastewater extracts gave a positive response in the PPAR assay, but these responses were not correlated with the amounts of any of the EDCs analyzed by LC-MS/MS. Overall, these data indicate that a step-wise approach is feasible using a combination of in vitro testing and instrumental analysis to monitor for

Interactions between the thyroid hormones and the hormones of the growth hormone axis.

Science.gov (United States)

Laron, Zvi

2003-12-01

The normal secretion and action of the thyroid hormones and the hormones of the GH/IGF-I (growth hormone/ insulin-like growth factor I) axis are interdependent. Their interactions often differ in man from animal studies in rodents and sheep. Thus neonates with congenital hypothyroidism are of normal length in humans but IUGR (intrauterine growth retardation) in sheep. Postnatally normal GH/IGF-I secretion and action depends on an euthyroid state. Present knowledge on the interactions between the two axes is reviewed in states of hypo- and hyperthyroidism, states of GH/IGF-I deprivation and hypersecretion, as well as the relationship between IGF-I and thyroid cancer. Emphasis is given to data in children and aspects of linear growth and skeletal maturation.

Salivary steroid hormone response to whole-body cryotherapy in elite rugby players.

Science.gov (United States)

Grasso, D; Lanteri, P; Di Bernardo, C; Mauri, C; Porcelli, S; Colombini, A; Zani, V; Bonomi, F G; Melegati, G; Banfi, G; Lombardi, G

2014-01-01

Saliva represents a low stress, not-invasively collected matrix that allows steroid hormone monitoring in athletes by reflecting type, intensity and duration of exercise. Whole body cryotherapy (WBC) consists of short whole-body exposures to extremely cold air (-110° to -140°C) which, despite being initially used to treat inflammatory diseases, is currently acquiring increasing popularity in sports medicine. Cryostimulation practice is now widely accepted as an effective treatment to accelerate muscle recovery in rugby players. The aim of this work was to study the changes of steroid hormones in saliva of rugby players after both 2 and 14 consecutive WBC sessions, in order to investigate the effects of the treatment on their salivary steroid hormonal profile. Twenty-five professional rugby players, belonging to the Italian National Team, underwent a 7-day cryotherapy protocol consisting of 2 daily sessions. Saliva samples were taken in the morning prior to the start of the WBC, in the evening after the end of the second WBC, and in the morning of the day after the last WBC session. The samples were analyzed for cortisol, DHEA, testosterone and estradiol using competitive enzyme-linked immunosorbent assays. Cortisol and DHEA showed a reduction already after the 2 WBC sessions of the first day; after 14 consecutive WBC sessions cortisol, DHEA, and estradiol levels decreased, while testosterone increased as did the testosterone to cortisol ratio. These results were confirmed by the fact that the majority of subjects showed variations exceeding the critical difference (CD). In conclusion, we found that WBC acutely affects the salivary steroid hormone profile, and the results are evident already after only one twice-daily session. Most significantly, after one-week of consecutive twice-daily WBC sessions, all the hormones were modified. This is the first experimental report that links changes in the hormonal asset to WBC.

Automated data processing and radioassays.

Science.gov (United States)

Samols, E; Barrows, G H

1978-04-01

Radioassays include (1) radioimmunoassays, (2) competitive protein-binding assays based on competition for limited antibody or specific binding protein, (3) immunoradiometric assay, based on competition for excess labeled antibody, and (4) radioreceptor assays. Most mathematical models describing the relationship between labeled ligand binding and unlabeled ligand concentration have been based on the law of mass action or the isotope dilution principle. These models provide useful data reduction programs, but are theoretically unfactory because competitive radioassay usually is not based on classical dilution principles, labeled and unlabeled ligand do not have to be identical, antibodies (or receptors) are frequently heterogenous, equilibrium usually is not reached, and there is probably steric and cooperative influence on binding. An alternative, more flexible mathematical model based on the probability or binding collisions being restricted by the surface area of reactive divalent sites on antibody and on univalent antigen has been derived. Application of these models to automated data reduction allows standard curves to be fitted by a mathematical expression, and unknown values are calculated from binding data. The vitrues and pitfalls are presented of point-to-point data reduction, linear transformations, and curvilinear fitting approaches. A third-order polynomial using the square root of concentration closely approximates the mathematical model based on probability, and in our experience this method provides the most acceptable results with all varieties of radioassays. With this curvilinear system, linear point connection should be used between the zero standard and the beginning of significant dose response, and also towards saturation. The importance is stressed of limiting the range of reported automated assay results to that portion of the standard curve that delivers optimal sensitivity. Published methods for automated data reduction of Scatchard plots

Commercial radioimmunoassay for beta subunit of human chorionic gonadotropin: falsely positive determinations due to elevated serum luteinizing hormone

International Nuclear Information System (INIS)

Fowler, J.E. Jr.; Platoff, G.E.; Kubrock, C.A.; Stuzman, R.E.

1982-01-01

Among 17 men who had received seemingly curative treatment for unilateral non-seminomatous germ cell tumors for the testis and who had consistently normal serum human chorionic gonadotropin (HCG) levels at a reference laboratory, 7 (41%) had at least one falsely positive commercial serum HCG determination. To investigate the cause of these falsely positive determinations the authors measured the cross reactivity of luteinizing hormone (LH) and follicle stimulating hormone (FSH) standards in the commercial HCG assay, and studied the relationships between commercial HCG levels and serum LH levels, serum FSH levels and gonadal status in men with and without normal gonadal function. The falsely positive HCG determinations appeared to be due to elevated serum LH levels and cross reactivity of LH in the commercial HCG assay because: 1) there was substantial cross reactivity of the LH standards in the commercial assay, 2) the serum LH was elevated in four of six men with solitary testes, 3) there was a striking correlation between elevated serum LH levels and falsely elevated commercial HCG levels in ten men with solitary or absent testes, and 4) there were no falsely positive HCG determinations in 13 normal men but there were falsely positive HCG determinations in seven of ten anorchid men

Allosteric activation of the follicle-stimulating hormone (FSH) receptor by selective, nonpeptide agonists.

Science.gov (United States)

Yanofsky, Stephen D; Shen, Emily S; Holden, Frank; Whitehorn, Erik; Aguilar, Barbara; Tate, Emily; Holmes, Christopher P; Scheuerman, Randall; MacLean, Derek; Wu, May M; Frail, Donald E; López, Francisco J; Winneker, Richard; Arey, Brian J; Barrett, Ronald W

2006-05-12

The pituitary glycoprotein hormones, luteinizing hormone and follicle-stimulating hormone (FSH), act through their cognate receptors to initiate a series of coordinated physiological events that results in germ cell maturation. Given the importance of FSH in regulating folliculogenesis and fertility, the development of FSH mimetics has been sought to treat infertility. Currently, purified and recombinant human FSH are the only FSH receptor (FSH-R) agonists available for infertility treatment. By screening unbiased combinatorial chemistry libraries, using a cAMP-responsive luciferase reporter assay, we discovered thiazolidinone agonists (EC50's = 20 microm) of the human FSH-R. Subsequent analog library screening and parallel synthesis optimization resulted in the identification of a potent agonist (EC50 = 2 nm) with full efficacy compared with FSH that was FSH-R-selective and -dependent. The compound mediated progesterone production in Y1 cells transfected with the human FSH-R (EC50 = 980 nm) and estradiol production from primary rat ovarian granulosa cells (EC50 = 10.5 nm). This and related compounds did not compete with FSH for binding to the FSH-R. Use of human FSH/thyroid-stimulating hormone (TSH) receptor chimeras suggested a novel mechanism for receptor activation through a binding site independent of the natural hormone binding site. This study is the first report of a high affinity small molecule agonist that activates a glycoprotein hormone receptor through an allosteric mechanism. The small molecule FSH receptor agonists described here could lead to an oral alternative to the current parenteral FSH treatments used clinically to induce ovarian stimulation for both in vivo and in vitro fertilization therapy.

Plurihormonal pituitary adenoma immunoreactive for thyroid-stimulating hormone, growth hormone, follicle-stimulating hormone, and prolactin.

Science.gov (United States)

Luk, Cynthia T; Kovacs, Kalman; Rotondo, Fabio; Horvath, Eva; Cusimano, Michael; Booth, Gillian L

2012-01-01

To describe the case of a patient with an unusual plurihormonal pituitary adenoma with immunoreactivity for thyroid-stimulating hormone (TSH), growth hormone, follicle-stimulating hormone, prolactin, and α-subunit. We report the clinical, laboratory, imaging, and pathology findings of a patient symptomatic from a plurihormonal pituitary adenoma and describe her outcome after surgical treatment. A 60-year-old woman presented to the emergency department with headaches, blurry vision, fatigue, palpitations, sweaty hands, and weight loss. Her medical history was notable for hyperthyroidism, treated intermittently with methimazole. Magnetic resonance imaging disclosed a pituitary macroadenoma (2.3 by 2.2 by 2.0 cm), and preoperative blood studies revealed elevated levels of TSH at 6.11 mIU/L, free thyroxine at 3.6 ng/dL, and free triiodothyronine at 6.0 pg/mL. She underwent an uncomplicated transsphenoidal resection of the pituitary adenoma. Immunostaining of tumor tissue demonstrated positivity for not only TSH but also growth hormone, follicle-stimulating hormone, prolactin, and α-subunit. The Ki-67 index of the tumor was estimated at 2% to 5%, and DNA repair enzyme O6-methylguanine-DNA methyltransferase immunostaining was mostly negative. Electron microscopy showed the ultrastructural phenotype of a glycoprotein-producing adenoma. Postoperatively, her symptoms and hyperthyroidism resolved. Thyrotropin-secreting pituitary adenomas are rare. Furthermore, recent reports suggest that 31% to 36% of adenomas may show evidence of secretion of multiple pituitary hormones. This case emphasizes the importance of considering pituitary causes of thyrotoxicosis and summarizes the clinical and pathology findings in a patient with a plurihormonal pituitary adenoma.

Correlation of skin changes with hormonal changes in polycystic ovarian syndrome: A cross-sectional study clinical study

Directory of Open Access Journals (Sweden)

B Vijaya Gowri

2015-01-01

Full Text Available Background: Polycystic ovarian syndrome (PCOS is a heterogenous collection of signs and symptoms that when gathered, form a spectrum of disorder with disturbance of reproductive, endocrine and metabolic functions. Aim: The aim of this study is to correlate the skin manifestations with hormonal changes and to know the incidence and prevalence of skin manifestations in patients with PCOS. Materials and Methods: A total of 40 patients with PCOS were examined during 1 year time period from May 2008 P to May 2009. Detailed clinical history was taken from each patient. PCOS was diagnosed on the basis of ultrasonography. Hormonal assays included fasting blood sugar, postprandial blood sugar, follicle-stimulating hormone, luteinizing hormone, thyroid stimulating hormone, dehydroepiandrostenedione, prolactin, free testosterone, fasting lipid profile and sex hormone binding globulin. The results obtained were statistically correlated. Results: In our study, the prevalence of cutaneous manifestations was 90%. Of all the cutaneous manifestations acne was seen in highest percentage (67.5%, followed by hirsutism (62.5%, seborrhea (52.5%, androgenetic alopecia (AGA (30%, acanthosis nigricans (22.5% and acrochordons (10%. Fasting insulin levels was the most common hormonal abnormality seen in both acne and hirsutism, whereas AGA was associated with high testosterone levels. Conclusion: The prevalence of cutaneous manifestations in PCOS was 90%. Hirsutism, acne, seborrhea, acanthosis nigricans and acrochordons were associated with increased levels of fasting insulin, whereas AGA showed higher levels of serum testosterone.

Is radiation-induced ovarian failure in rhesus monkeys preventable by luteinizing hormone-releasing hormone agonists?: Preliminary observations

International Nuclear Information System (INIS)

Ataya, K.; Pydyn, E.; Ramahi-Ataya

1995-01-01

With the advent of cancer therapy, increasing numbers of cancer patients are achieving long term survival. Impaired ovarian function after radiation therapy has been reported in several studies. Some investigators have suggested that luteinizing hormone-releasing hormone agonists (LHRHa) can prevent radiation-induced ovarian injury in rodents. Adult female rhesus monkeys were given either vehicle or Leuprolide acetate before, during, and after radiation. Radiation was given in a dose of 200 rads/day for a total of 4000 rads to the ovaries. Frequent serum samples were assayed for estradiol (E 2 ) and FSH. Ovariectomy was performed later. Ovaries were processed and serially sectioned. Follicle count and size distribution were determined. Shortly after radiation started, E 2 dropped to low levels, at which it remained, whereas serum FSH level, which was low before radiation, rose soon after starting radiation. In monkeys treated with a combination of LHRHa and radiation, FSH started rising soon after the LHRHa-loaded minipump was removed (after the end of radiation). Serum E 2 increased after the end of LHRHa treatment in the non-irradiated monkey, but not in the irradiated monkey. Follicle counts were not preserved in the LHRHa-treated monkeys that received radiation. The data demonstrated no protective effect of LHRHa treatment against radiation-induced ovarian injury in this rhesus monkey model. 58 refs., 2 figs., 1 tab

The Influence of Thyroid Hormones on Leptin and Resistin Levels in Hyperthyroid Female Patients

Directory of Open Access Journals (Sweden)

Al-Hindawi Sahar H

2018-01-01

Full Text Available Background: Hyperthyroidism or thyrotoxicosis occurs due to excess release of thyroid hormone. These hormones regulate the body’s energy balance and have effects on adipokine level. There are several reports suggesting interrelation between adipokines (resistin and leptin with thyroid dysfunction. Objectives: This study was established to investigate the effect of thyroid hormones in hyperthyroidism state on the level of some adipokines, leptin and resistin; in comparison with control. Patients and Methods: The present study included 50 Iraqi female patients with hyperthyroidism with age ranged between 30-58 years and 30 healthy controls with age ranged between 30-53 years. Serum samples were collected from study groups. The levels of thyroid hormones (TSH, T4 and T3 were determined by using automated Chemiluminescence Immunoassay (CLIA analysis system. Detection of leptin hormone and resistin hormone levels in the serum were determined by an enzyme linked immunosorbent assay (ELISA kits. Results: The results revealed that serum leptin levels were significantly low (P<0.004 in hyperthyroid patient groups as compared to control, and there were significant negative correlations between T4 and leptin (P<0.0001; also, T3 and leptin (P<0.05. Resistin hormone level increased non-significantly (P˃0.05 than control level; and there was significant negative correlation between TSH and resistin (P<0.035. Conclusion: The study shows that there is complex interrelation between adipocytokines (leptin and resistin with thyroid gland and pituitary gland. Leptin levels were decreased in hyperthyroid patients than control and associated negatively with T4 and T3 levels, while resistin levels were increased non-significantly than control and associated negatively with TSH level. They affect each other in their physiological function in the human body.

Gonadotropin-releasing hormone radioimmunoassay and its measurement in normal human plasma, secondary amenorrhea, and postmenopausal syndrome

International Nuclear Information System (INIS)

Rosenblum, N.G.; Schlaff, S.

1976-01-01

A sensitive and specific double antibody radioimmunoassay for gonadotropin-releasing hormone (GnRH) has been developed for measurement in ethanol extracts of human plasma. Iodinated hormone was prepared with the use of the chloramine-T method, and antibodies were developed in rabbits over a six-month period with a GnRH synthetic copolymer immunogen. A Scatchard plot revealed at least three species of antibody. The assay can measure conservatively at the 5 pg. per milliliter level and shows no cross-reactivity with other available hypothalamic and pituitary hormones. The releasing hormone was quantitatively recovered from human plasma with immunologic identity to native hormone. Unextracted plasma could not be used because of nonspecific displacement. The measurement of GnRH in individuals receiving 100 μg of intravenous bolus infusions of the synthetic decapeptide show extremely elevated values with two half-lives: one of two to four minutes and another of 35 to 40 minutes. In our experiments, we have found measurable GnRH in patients with secondary amenorrhea and at the midcycle in normal women. In the normal cycling woman during the follicular and luteal phases, GnRH was undetectable. In postmenopausal women with extreme hypoestrogenism and markedly elevated luteinizing hormone values, GnRH was also undetectable. No bursts of GnRH could be detected in normal men when sampled every ten minutes over a two-hour period and every two hours throughout the day

Role of stress-related hormones in plant defence during early infection of the cyst nematode Heterodera schachtii in Arabidopsis

Science.gov (United States)

Kammerhofer, Nina; Radakovic, Zoran; Regis, Jully M A; Dobrev, Petre; Vankova, Radomira; Grundler, Florian M W; Siddique, Shahid; Hofmann, Julia; Wieczorek, Krzysztof

2015-01-01

Heterodera schachtii, a plant-parasitic cyst nematode, invades host roots and induces a specific syncytial feeding structure, from which it withdraws all required nutrients, causing severe yield losses. The system H. schachtii–Arabidopsis is an excellent research model for investigating plant defence mechanisms. Such responses are suppressed in well-established syncytia, whereas they are induced during early parasitism. However, the mechanisms by which the defence responses are modulated and the role of phytohormones are largely unknown. The aim of this study was to elucidate the role of hormone-based defence responses at the onset of nematode infection. First, concentrations of main phytohormones were quantified and the expression of several hormone-related genes was analysed using quantitative real-time (qRT)-PCR or GeneChip. Further, the effects of individual hormones were evaluated via nematode attraction and infection assays using plants with altered endogenous hormone concentrations. Our results suggest a pivotal and positive role for ethylene during nematode attraction, whereas jasmonic acid triggers early defence responses against H. schachtii. Salicylic acid seems to be a negative regulator during later syncytium and female development. We conclude that nematodes are able to impose specific changes in hormone pools, thus modulating hormone-based defence and signal transduction in strict dependence on their parasitism stage. PMID:25825039

The role of Sep (O-phosphoserine) tRNA: Sec (selenocysteine) synthase (SEPSECS) in proliferation, apoptosis and hormone secretion of trophoblast cells.

Science.gov (United States)

Zhao, H-D; Zhang, W-G; Sun, M-N; Duan, Q-F; Li, F-L; Li, H

2013-11-01

To investigate whether Sep (O-phosphoserine) tRNA: Sec (selenocysteine) synthase (SEPSECS), which plays an essential role in the synthesis of selenoprotein, affects proliferation, apoptosis and hormone secretion of human trophoblast cells. Human trophoblast JEG-3 cells were divided into four groups: control group, SEPSECS silenced-expression group, empty vector group and SEPSECS over-expression group. Over-expression and silenced-expression were achieved by transfection with plasmid DNA or RNA oligonucleotide, respectively. 3-[4,5-dimethylthiazol-2-yl] -2,5-diphenyltetrazolium bromide (MTT) and colony formation assays were performed to investigate cell proliferation, while apoptosis was tested by annexin V-FITC, PI double staining and caspases-3 activation assays, enzyme-linked immunosorbent assay (ELISA) was used to determine the level of progesterone (PG) and human chorionic gonadotropin (hCG). SEPSECS silenced-expression clearly inhibited proliferation of JEG-3 cells (p < 0.05), significantly induced cell apoptosis (p < 0.01) and reduced the production of PG and hCG (p < 0.05). On the contrary, SEPSECS over-expression significantly promoted both cell proliferation (p < 0.01) and secretion of PG and hCG (p < 0.05). SEPSECS significantly affects proliferation, apoptosis and hormone secretion of human trophoblast cells, suggesting that a potential relationship exists among SEPSECS, cell proliferation, apoptosis and hormone production of human placental trophoblast cells. Furthermore, this may provide a clue to uncover the relationship between selenium and human placental in association with an emphasis on the importance of selenium adequacy during pregnancy. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Clinical study on the postburn change in the hypothalamus-pituitary-adrenal hormones in severely burned patients].

Science.gov (United States)

Li, Hong-mian; Liang, Zi-qian; Luo, Zuo-jie

2003-06-01

To investigate the postburn dynamic changes in the hypothalamus-pituitary-adrenal hormones in severely burned patients. Fifty burn patients were enrolled in the study. The plasma contents of total GC (cortisol), ACTH and aldosterone (ALDO) and urinary contents of 17-OHO and 17-KS were determined with radio-immunological assay (RIA) method after burn injury to compare with the normal values which were well established clinically. The postburn plasma and urinary contents of the above indices were increased evidently with two peak values in shock and infectious stages, whilst the majority of he indices were lower than the normal values after 6 postburn weeks (PBWs). The values of these hormones were the lowest in dying patients. On the other hand, the values approached normal levels in those patients whose burn wounds were healing. Increases of the plasma and urinary levels of hypothalamus-pituitary -adrenal hormones in severely burned patients were constantly seen. Burn shock and infection seemed to be the two major factors in inducing postburn stress reaction in burn victims. Abrupt decrease of the hormone levels in plasma and or urine indicated adrenal failure predicting a poor prognosis of the burn patients.

Antimüllerian hormone in gonadotropin releasing-hormone antagonist cycles

DEFF Research Database (Denmark)

Arce, Joan-Carles; La Marca, Antonio; Mirner Klein, Bjarke

2013-01-01

To assess the relationships between serum antimüllerian hormone (AMH) and ovarian response and treatment outcomes in good-prognosis patients undergoing controlled ovarian stimulation using a gonadotropin-releasing hormone (GnRH) antagonist protocol....

Gastrointestinal hormones and their targets

DEFF Research Database (Denmark)

Rehfeld, Jens F.

2014-01-01

Gastrointestinal hormones are peptides released from endocrine cells and neurons in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gastrointestinal tract, which makes the gut the largest hormone producing organ in the body. Modern biology makes...... it feasible to conceive the hormones under five headings: The structural homology groups a majority of the hormones into nine families, each of which is assumed to originate from one ancestral gene. The individual hormone gene often has multiple phenotypes due to alternative splicing, tandem organization......, or differentiated maturation of the prohormone. By a combination of these mechanisms, more than 100 different hormonally active peptides are released from the gut. Gut hormone genes are also widely expressed in cells outside the gut, some only in extraintestinal endocrine cells and neurons but others also in other...

Missed hormonal contraceptives: new recommendations.

Science.gov (United States)

Guilbert, Edith; Black, Amanda; Dunn, Sheila; Senikas, Vyta

2008-11-01

To provide evidence-based guidance for women and their health care providers on the management of missed or delayed hormonal contraceptive doses in order to prevent unintended pregnancy. Medline, PubMed, and the Cochrane Database were searched for articles published in English, from 1974 to 2007, about hormonal contraceptive methods that are available in Canada and that may be missed or delayed. Relevant publications and position papers from appropriate reproductive health and family planning organizations were also reviewed. The quality of evidence is rated using the criteria developed by the Canadian Task Force on Preventive Health Care. This committee opinion will help health care providers offer clear information to women who have not been adherent in using hormonal contraception with the purpose of preventing unintended pregnancy. The Society of Obstetricians and Gynaecologists of Canada. SUMMARY STATEMENTS: 1. Instructions for what women should do when they miss hormonal contraception have been complex and women do not understand them correctly. (I) 2. The highest risk of ovulation occurs when the hormone-free interval is prolonged for more than seven days, either by delaying the start of combined hormonal contraceptives or by missing active hormone doses during the first or third weeks of combined oral contraceptives. (II) Ovulation rarely occurs after seven consecutive days of combined oral contraceptive use. (II) RECOMMENDATIONS: 1. Health care providers should give clear, simple instructions, both written and oral, on missed hormonal contraceptive pills as part of contraceptive counselling. (III-A) 2. Health care providers should provide women with telephone/electronic resources for reference in the event of missed or delayed hormonal contraceptives. (III-A) 3. In order to avoid an increased risk of unintended pregnancy, the hormone-free interval should not exceed seven days in combined hormonal contraceptive users. (II-A) 4. Back-up contraception should

Thyroid hormone receptor inhibits hepatoma cell migration through transcriptional activation of Dickkopf 4

Energy Technology Data Exchange (ETDEWEB)

Chi, Hsiang-Cheng; Liao, Chen-Hsin [Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC (China); Huang, Ya-Hui [Medical Research Central, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan, ROC (China); Wu, Sheng-Ming; Tsai, Chung-Ying; Liao, Chia-Jung; Tseng, Yi-Hsin; Lin, Yang-Hsiang; Chen, Cheng-Yi; Chung, I-Hsiao; Wu, Tzu-I [Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC (China); Chen, Wei-Jan [First Cardiovascular Division, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan, ROC (China); Lin, Kwang-Huei, E-mail: khlin@mail.cgu.edu.tw [Department of Biochemistry, School of Medicine, Chang-Gung University, Taoyuan 333, Taiwan, ROC (China)

2013-09-13

Highlights: •T{sub 3} affects DKK4 mRNA and protein expression in HepG2-TR cells. •Regulation of DKK4 by T{sub 3} is at transcriptional level. •DKK4 overexpression suppresses hepatoma cell metastasis. -- Abstract: Triiodothyronine (T{sub 3}) is a potent form of thyroid hormone mediates several physiological processes including cellular growth, development, and differentiation via binding to the nuclear thyroid hormone receptor (TR). Recent studies have demonstrated critical roles of T{sub 3}/TR in tumor progression. Moreover, long-term hypothyroidism appears to be associated with the incidence of human hepatocellular carcinoma (HCC), independent of other major HCC risk factors. Dickkopf (DKK) 4, a secreted protein that antagonizes the canonical Wnt signaling pathway, is induced by T{sub 3} at both mRNA and protein levels in HCC cell lines. However, the mechanism underlying T{sub 3}-mediated regulation of DKK4 remains unknown. In the present study, the 5′ promoter region of DKK4 was serially deleted, and the reporter assay performed to localize the T{sub 3} response element (TRE). Consequently, we identified an atypical direct repeat TRE between nucleotides −1645 and −1629 conferring T{sub 3} responsiveness to the DKK4 gene. This region was further validated using chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA). Stable DKK4 overexpression in SK-Hep-1 cells suppressed cell invasion and metastatic potential, both in vivo andin vitro, via reduction of matrix metalloproteinase-2 (MMP-2) expression. Our findings collectively suggest that DKK4 upregulated by T{sub 3}/TR antagonizes the Wnt signal pathway to suppress tumor cell progression, thus providing new insights into the molecular mechanism underlying thyroid hormone activity in HCC.

Chronic food restriction and the circadian rhythms of pituitary-adrenal hormones, growth hormone and thyroid-stimulating hormone.

Science.gov (United States)

Armario, A; Montero, J L; Jolin, T

1987-01-01

Adult male Sprague-Dawley rats were subjected to food restriction so that they ate 65% of food ingested by control rats. While control rats had free access to food over the 24-hour period, food-restricted rats were provided with food daily at 10 a.m. The experimental period lasted for 34 days. On day 35, rats from both experimental groups were killed at 08.00, 11.00, 14.00, 24.00 and 02.00 h. Food restriction modified the circadian rhythms of ACTH and corticosterone. In addition, total circulating corticosterone throughout the day was higher in food-restricted than in control rats. In contrast, food restriction resulted in depressed secretion of thyroid-stimulating hormone and growth hormone. The results indicate that time of food availability entrained circadian corticosterone rhythm but not thyroid-stimulating hormone and growth hormone rhythms.

Thyroid hormone upregulates zinc-α2-glycoprotein production in the liver but not in adipose tissue.

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Rafael Simó

Full Text Available Overproduction of zinc-α2-glycoprotein by adipose tissue is crucial in accounting for the lipolysis occurring in cancer cachexia of certain malignant tumors. The main aim of this study was to explore whether thyroid hormone could enhance zinc-α2-glycoprotein production in adipose tissue. In addition, the regulation of zinc-α2-glycoprotein by thyroid hormone in the liver was investigated. We performed in vitro (HepG2 cells and primary human adipocytes and in vivo (C57BL6/mice experiments addressed to examine the effect of thyroid hormone on zinc-α2-glycoprotein production (mRNA and protein levels in liver and visceral adipose tissue. We also measured the zinc-α2-glycoprotein serum levels in a cohort of patients before and after controlling their hyperthyroidism. Our results showed that thyroid hormone up-regulates zinc-α2-glycoprotein production in HepG2 cells in a dose-dependent manner. In addition, the zinc-α2-glycoprotein proximal promoter contains functional thyroid hormone receptor binding sites that respond to thyroid hormone treatment in luciferase reporter gene assays in HepG2 cells. Furthermore, zinc-α2-glycoprotein induced lipolysis in HepG2 in a dose-dependent manner. Our in vivo experiments in mice confirmed the up-regulation of zinc-α2-glycoprotein induced by thyroid hormone in the liver, thus leading to a significant increase in zinc-α2-glycoprotein circulating levels. However, thyroid hormone did not regulate zinc-α2-glycoprotein production in either human or mouse adipocytes. Finally, in patients with hyperthyroidism a significant reduction of zinc-α2-glycoprotein serum levels was detected after treatment but was unrelated to body weight changes. We conclude that thyroid hormone up-regulates the production of zinc-α2-glycoprotein in the liver but not in the adipose tissue. The neutral effect of thyroid hormones on zinc-α2-glycoprotein expression in adipose tissue could be the reason why zinc-α2-glycoprotein is not

Thyroid hormone upregulates zinc-α2-glycoprotein production in the liver but not in adipose tissue.

Science.gov (United States)

Simó, Rafael; Hernández, Cristina; Sáez-López, Cristina; Soldevila, Berta; Puig-Domingo, Manel; Selva, David M

2014-01-01

Overproduction of zinc-α2-glycoprotein by adipose tissue is crucial in accounting for the lipolysis occurring in cancer cachexia of certain malignant tumors. The main aim of this study was to explore whether thyroid hormone could enhance zinc-α2-glycoprotein production in adipose tissue. In addition, the regulation of zinc-α2-glycoprotein by thyroid hormone in the liver was investigated. We performed in vitro (HepG2 cells and primary human adipocytes) and in vivo (C57BL6/mice) experiments addressed to examine the effect of thyroid hormone on zinc-α2-glycoprotein production (mRNA and protein levels) in liver and visceral adipose tissue. We also measured the zinc-α2-glycoprotein serum levels in a cohort of patients before and after controlling their hyperthyroidism. Our results showed that thyroid hormone up-regulates zinc-α2-glycoprotein production in HepG2 cells in a dose-dependent manner. In addition, the zinc-α2-glycoprotein proximal promoter contains functional thyroid hormone receptor binding sites that respond to thyroid hormone treatment in luciferase reporter gene assays in HepG2 cells. Furthermore, zinc-α2-glycoprotein induced lipolysis in HepG2 in a dose-dependent manner. Our in vivo experiments in mice confirmed the up-regulation of zinc-α2-glycoprotein induced by thyroid hormone in the liver, thus leading to a significant increase in zinc-α2-glycoprotein circulating levels. However, thyroid hormone did not regulate zinc-α2-glycoprotein production in either human or mouse adipocytes. Finally, in patients with hyperthyroidism a significant reduction of zinc-α2-glycoprotein serum levels was detected after treatment but was unrelated to body weight changes. We conclude that thyroid hormone up-regulates the production of zinc-α2-glycoprotein in the liver but not in the adipose tissue. The neutral effect of thyroid hormones on zinc-α2-glycoprotein expression in adipose tissue could be the reason why zinc-α2-glycoprotein is not related to weight

Gut hormones and gastric bypass

DEFF Research Database (Denmark)

Holst, Jens J.

2016-01-01

Gut hormone secretion in response to nutrient ingestion appears to depend on membrane proteins expressed by the enteroendocrine cells. These include transporters (glucose and amino acid transporters), and, in this case, hormone secretion depends on metabolic and electrophysiological events elicited...... that determines hormone responses. It follows that operations that change intestinal exposure to and absorption of nutrients, such as gastric bypass operations, also change hormone secretion. This results in exaggerated increases in the secretion of particularly the distal small intestinal hormones, GLP-1, GLP-2......, oxyntomodulin, neurotensin and peptide YY (PYY). However, some proximal hormones also show changes probably reflecting that the distribution of these hormones is not restricted to the bypassed segments of the gut. Thus, cholecystokinin responses are increased, whereas gastric inhibitory polypeptide responses...

Adult growth hormone deficiency

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Vishal Gupta

2011-01-01

Full Text Available Adult growth hormone deficiency (AGHD is being recognized increasingly and has been thought to be associated with premature mortality. Pituitary tumors are the commonest cause for AGHD. Growth hormone deficiency (GHD has been associated with neuropsychiatric-cognitive, cardiovascular, neuromuscular, metabolic, and skeletal abnormalities. Most of these can be reversed with growth hormone therapy. The insulin tolerance test still remains the gold standard dynamic test to diagnose AGHD. Growth hormone is administered subcutaneously once a day, titrated to clinical symptoms, signs and IGF-1 (insulin like growth factor-1. It is generally well tolerated at the low-doses used in adults. Pegylated human growth hormone therapy is on the horizon, with a convenient once a week dosing.

The measurement of serum human parathyroid hormone (h-PTH53-84) and effect of exercise on calcium metabolism

International Nuclear Information System (INIS)

Torizumi, Kazutami; Taniguchi, Yoshiyuki; Aibata, Hirofumi; Kiji, Shigeyuki; Ueyoshi, Akitaka; Shimizu, Eiji; Okamoto, Yukiharu; Tuda, Tadaaki; Ota, Kiichiro

1987-01-01

This study was focussed our attention on the measurement within the upper physiological level of human serum parathyroid hormone (PTH), using kits of human PTH 53 - 84. This assay kit was able to detect serum PTH in sera with suble changes of serum calcium concentrations before and after short term exercise. These serum PTH levels before and after exercise seemed to be changed within the upper physiological levels of PTH. Thus, this study suggested that the assay kit was likely to become a useful tool of the measurement of the physiological level of serum PTH in humans. (author)

Silent pituitary macroadenoma co-secreting growth hormone and thyroid stimulating hormone.

Science.gov (United States)

Sen, Orhan; Ertorer, M Eda; Aydin, M Volkan; Erdogan, Bulent; Altinors, Nur; Zorludemir, Suzan; Guvener, Nilgun

2005-04-01

Silent pituitary adenomas are a group of tumors showing heterogenous morphological features with no hormonal function observed clinically. To date no explanation has been provided as to why these tumors remain "silent". We report a case of a silent macroadenoma with both growth hormone (GH) and thyroid stimulating hormone (TSH) staining and secretion but with no clinical manifestations, in particular, the absence of features of acromegaly or hyperthyroidism. The relevant literature is reviewed.

Alternatives to in vivo tests to detect endocrine disrupting chemicals (EDCs) in fish and amphibians--screening for estrogen, androgen and thyroid hormone disruption.

Science.gov (United States)

Scholz, S; Renner, P; Belanger, S E; Busquet, F; Davi, R; Demeneix, B A; Denny, J S; Léonard, M; McMaster, M E; Villeneuve, D L; Embry, M R

2013-01-01

Endocrine disruption is considered a highly relevant hazard for environmental risk assessment of chemicals, plant protection products, biocides and pharmaceuticals. Therefore, screening tests with a focus on interference with estrogen, androgen, and thyroid hormone pathways in fish and amphibians have been developed. However, they use a large number of animals and short-term alternatives to animal tests would be advantageous. Therefore, the status of alternative assays for endocrine disruption in fish and frogs was assessed by a detailed literature analysis. The aim was to (i) determine the strengths and limitations of alternative assays and (ii) present conclusions regarding chemical specificity, sensitivity, and correlation with in vivo data. Data from 1995 to present were collected related to the detection/testing of estrogen-, androgen-, and thyroid-active chemicals in the following test systems: cell lines, primary cells, fish/frog embryos, yeast and cell-free systems. The review shows that the majority of alternative assays measure effects directly mediated by receptor binding or resulting from interference with hormone synthesis. Other mechanisms were rarely analysed. A database was established and used for a quantitative and comparative analysis. For example, a high correlation was observed between cell-free ligand binding and cell-based reporter cell assays, between fish and frog estrogenic data and between fish embryo tests and in vivo reproductive effects. It was concluded that there is a need for a more systematic study of the predictive capacity of alternative tests and ways to reduce inter- and intra-assay variability.

The association of total antioxidant capacity with sex hormones.

Science.gov (United States)

Demirbag, Recep; Yilmaz, Remzi; Erel, Ozcan

2005-07-01

Although sex hormones have potential cardioprotective effects, their effects on total antioxidant capacity (TAC) are not very well known. The aim of the study was to evaluate TAC in men who have decreased and normal testosterone levels and in women in menopausal and premenopausal period. Ninety-seven subjects with similar age intervals, men aged <45 years and female aged <50 years, were divided into four groups: 1) 10 men with normal testosterone levels, as control, 2) 36 men with decreased testosterone, 3) 19 women in menopause, surgically induced, and 4) 32 women in premenopausal period. Testosterone and estrogen levels were measured by chemiluminescence assay and TAC were measured by using a more recently developed automated measurement method. The TAC was significantly lower in Group 2 and Group 3 than those of Group 1 and Group 4 (ANOVA, p<0.001). A strong correlation between TAC, and testosterone and estrogen were found (r=0.807, p<0.001; r=0.685, p<0.001, testosterone and estrogen respectively). The observed relationship between sex hormones and TAC may have a role in mechanism of their cardioprotective effect.

Neuromuscular performance of elite rugby union players and relationships with salivary hormones.

Science.gov (United States)

Crewther, Blair T; Lowe, Tim; Weatherby, Robert P; Gill, Nicholas; Keogh, Justin

2009-10-01

This study compared the neuromuscular performance (speed, power, strength) of elite rugby union players, by position, and examined the relationship between player performance and salivary hormones, by squad and position. Thirty-four professional male rugby players were assessed for running speed (10-m, 20-m or 30-m sprints), concentric mean (MP) and peak power (PP) during a 70-kg squat jump (SJ) and 50-kg bench press throw (BT), and estimated 1 repetition maximum (1RM) strength for a box squat (BS) and bench press (BP). Tests were performed on separate days with absolute and normalized (power and strength only) values computed. Saliva was collected before each test and assayed for testosterone (Sal-T) and cortisol (Sal-C). In absolute terms, the backs demonstrated greater speed and BT MP, whereas the forwards produced greater SJ PP and MP and BS 1RM (p 0.05). A comparison (absolute and normalized) of BT PP showed no positional differences (p > 0.05), whereas BP 1RM was greater for the forwards (p rugby. The Sal-T and/or Sal-C concentrations of players correlated to speed, power, and strength, especially for the backs (p benefit from acute and chronic hormone monitoring to identify those individuals likely to respond more to hormonal change.

The utility and dynamics of salivary sex hormone measurements in the National Social Life, Health, and Aging Project, Wave 2.

Science.gov (United States)

Kozloski, Michael J; Schumm, L Philip; McClintock, Martha K

2014-11-01

Sex hormones affect physical, mental, and social health, yet their role in mediating social effects on aging is understudied. To facilitate such analyses with the National Social Life, Health & Aging Project Wave 2, we summarize the conceptual background, collection protocols, laboratory assays, and data analysis strategies for biologically active (free) levels of testosterone, estradiol, progesterone, and dehydroepiandrosterone (DHEA). Saliva from passive drool was collected from returning Wave 1 respondents and non-respondents as well as their partners during an in-home interview. Specimens were frozen and sent to Dresden LabService GmbH for duplicate assays of biologically active steroids using identical assay kits from National Social Life, Health, and Aging Project (NSHAP) Wave 1 (SaliCap, Catalog No. RE69995). Overall, 2,772 testosterone, 2,504 estradiol, 2,714 progesterone, and 2,800 DHEA measurements are publically available for Wave 2 analyses. Through a series of weighted linear regressions, all 4 steroids are compared by gender and age and to Wave 1 measurements. Men had higher levels of both free testosterone and progesterone than women; women and men had the same levels of estradiol and DHEA. Both free testosterone and DHEA decreased with age. We also found significant wave effects for all 4 sex hormones. NSHAP Waves 1 and 2 are the first U.S. probability sample studies to measure these 4 salivary sex hormones simultaneously, providing individual profiles 5 years apart. Wave 2 data demonstrate differences by gender and trends by age that are similar to those found in other saliva-based and serum-based studies of free steroid levels. The differences between waves arising from the change in assay laboratory need to be adjusted in future longitudinal analyses using NSHAP Wave 1 and Wave 2 steroid data. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e

Pituitary Gonadotropins, Prolactin and Growth Hormone Differentially Regulate AQP1 Expression in the Porcine Ovarian Follicular Cells

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Mariusz T. Skowronski

2017-12-01

Full Text Available The present in vitro study analyzed whether the hormones that affect the ovarian follicular steroidogenesis process also participate in the regulation of AQP1 mRNA and protein expression. Granulosa (Gc and theca cells (Tc of medium and large porcine ovarian follicles were exposed to follicle-stimulating hormone (FSH, luteinizing hormone (LH, prolactin (PRL and growth hormone (GH for 24 h in separated cells and co-cultures of these cells. Real-time PCR, Western blotting, immunofluorescence and volumetric analysis were then performed. Gonadotropins, PRL and GH had a stimulatory impact on AQP1 mRNA and protein expression in Gc and Tc of medium and large ovarian cells. Moreover, swelling assays, in response to a hypotonic environment, demonstrated the functional presence of AQPs in porcine Gc and Tc. Immunofluorescence analysis showed that AQP1 protein was mainly localized in the perinuclear region of the cytoplasm, endosomes and cell membranes of Gc and Tc from medium and large follicles. It seems possible that AQP1 present in Gc and Tc cells may be implicated not only in the regulation of water homeostasis required for follicle development but also in cell proliferation and migration.

Heterologous humoral immune response in patients treated with human growth hormone from different sources

International Nuclear Information System (INIS)

Cardoso, A.I.; Llera, A.S.; Iacono, R.F.

1993-01-01

The existence of homologous anti-human growth hormone (anti-hGH) and heterologous anti-bovine growth hormone (anti-bGH) humoral immune responses in hypopituitary patients under hGH therapy has been reported previously. In order to study the influence of the hormone source, both responses were compared by radiobinding assays performed with [ 125 I]hGH or [ 125 I]bGH as tracers. 57 hypopituitary patients treated with extractive hGH, recombinant methionyl hGH or authentic recombinant hGH were studied. A very low incidence of heterologous antibodies was found in patients under recombinant hGH therapy, contrary to the high incidence observed in patients treated with extractive hGH preparations. In addition, immunochemical studies performed with a synthetic peptide (hGH 44-128) indicated that this peptide exhibited, in the anti-bGH/[ 125 I]bGH radioimmunoassay system, higher reactivity than the native hGH, suggesting that such fragment resembled an altered conformation of the hormone. The high heterologous response elicited only by the extractive hGH along with the behaviour of the hGH 44-128 fragment supports the fact that the extraction and purification procedures in extractive preparations may alter slightly the structure of the hGH molecule and trigger a heterologous immune response. 16 refs., 4 figs., 1 tab

Heterologous humoral immune response in patients treated with human growth hormone from different sources

Energy Technology Data Exchange (ETDEWEB)

Cardoso, A.I.; Llera, A.S.; Iacono, R.F. (and others) (Inst. de Estudios de la Inmunidad Humoral, Buenos Aires (Argentina))

1993-07-01

The existence of homologous anti-human growth hormone (anti-hGH) and heterologous anti-bovine growth hormone (anti-bGH) humoral immune responses in hypopituitary patients under hGH therapy has been reported previously. In order to study the influence of the hormone source, both responses were compared by radiobinding assays performed with [[sup 125]I]hGH or [[sup 125]I]bGH as tracers. 57 hypopituitary patients treated with extractive hGH, recombinant methionyl hGH or authentic recombinant hGH were studied. A very low incidence of heterologous antibodies was found in patients under recombinant hGH therapy, contrary to the high incidence observed in patients treated with extractive hGH preparations. In addition, immunochemical studies performed with a synthetic peptide (hGH 44-128) indicated that this peptide exhibited, in the anti-bGH/[[sup 125]I]bGH radioimmunoassay system, higher reactivity than the native hGH, suggesting that such fragment resembled an altered conformation of the hormone. The high heterologous response elicited only by the extractive hGH along with the behaviour of the hGH 44-128 fragment supports the fact that the extraction and purification procedures in extractive preparations may alter slightly the structure of the hGH molecule and trigger a heterologous immune response. 16 refs., 4 figs., 1 tab.

Pituitary mammosomatotroph adenomas develop in old mice transgenic for growth hormone-releasing hormone

DEFF Research Database (Denmark)

Asa, S L; Kovacs, K; Stefaneanu, L

1990-01-01

It has been shown that mice transgenic for human growth hormone-releasing hormone (GRH) develop hyperplasia of pituitary somatotrophs and mammosomatotrophs, cells capable of producing both growth hormone and prolactin, by 8 months of age. We now report for the first time that old GRH-transgenic...

Menopause and Hormones

Science.gov (United States)

... Consumer Information by Audience For Women Menopause and Hormones: Common Questions Share Tweet Linkedin Pin it More ... reproduction and distribution. Learn More about Menopause and Hormones Menopause--Medicines to Help You Links to other ...

An homologous radioimmunoassay for chicken follicle-stimulating hormone: observations on the ovulatory cycle

International Nuclear Information System (INIS)

Scanes, C.G.; Godden, P.M.M.; Sharp, P.J.

1977-01-01

A highly purified FSH preparation has been used to develop a specific homologous radio-immunoassay for chicken FSH which is sufficiently sensitive and precise to measure the hormone in small samples (10-100 μl) of plasma. The assay was used to measure plasma FSH in the chicken and turkey. The FSH concentration was higher in sexually mature chickens than in juvenile birds and further elevated after castration or ovariectomy. In turkeys, it was lower in birds held on a short daily photoperiod than in birds held on a long daily photoperiod. FSH rose in sexually quiescent female turkeys after injection of synthetic L-H releasing hormone and was increased in laying hens after injection of progesterone. No major changes were observed in FSH concentration during the chicken ovulatory cycle, although there was a small increase between 15 and 14 h before ovulation. (author)

Tomato transcriptome and mutant analyses suggest a role for plant stress hormones in the interaction between fruit and Botrytis cinerea

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Barbara eBlanco-Ulate

2013-05-01

Full Text Available Fruit-pathogen interactions are a valuable biological system to study the role of plant development in the transition from resistance to susceptibility. In general, unripe fruit are resistant to pathogen infection but become increasingly more susceptible as they ripen. During ripening, fruit undergo significant physiological and biochemical changes that are coordinated by complex regulatory and hormonal signaling networks. The interplay between multiple plant stress hormones in the interaction between plant vegetative tissues and microbial pathogens has been documented extensively, but the relevance of these hormones during infections of fruit is unclear. In this work, we analyzed a transcriptome study of tomato fruit infected with Botrytis cinerea in order to profile the expression of genes for the biosynthesis, modification and signal transduction of ethylene (ET, salicylic acid (SA, jasmonic acid (JA, and abscisic acid (ABA, hormones that may be not only involved in ripening, but also in fruit interactions with pathogens. The changes in relative expression of key genes during infection and assays of susceptibility of fruit with impaired synthesis or perception of these hormones were used to formulate hypotheses regarding the involvement of these regulators in the outcome of the tomato fruit-B. cinerea interaction.

The role of anti-Müllerian hormone in female fertility and infertility - an overview

DEFF Research Database (Denmark)

Grynnerup, Anna Garcia-Alix; Lindhard, Anette; Sørensen, Steen

2012-01-01

and hyper-responses. However, recent research has also highlighted the use of AMH in a variety of ovarian pathological conditions, including polycystic ovary syndrome, granulosa cell tumors and premature ovarian failure. A new commercial enzyme-linked immunosorbent assay for measuring AMH levels has been......Anti-Müllerian hormone (AMH) plasma levels reflect the continuous non-cyclic growth of small follicles, thereby mirroring the size of the resting primordial follicle pool and thus acting as a useful marker of ovarian reserve. Anti-Müllerian hormone seems to be the best endocrine marker...... for assessing the age-related decline of the ovarian pool in healthy women; thus, it has a potential ability to predict future reproductive lifespan. The most established role for AMH measurements is before in vitro fertilization is initiated, because AMH can be predictive of the ovarian response, namely poor...

Thyroid Hormone Treatment

Science.gov (United States)

... THYROID HORMONES? Desiccated ( dried and powdered ) animal thyroid ( Armour ®), now mainly obtained from pigs, was the most ... hormone can increase the risk or heart rhythm problems and bone loss making the use of thyroxine ...

Obesity Related Alterations in Plasma Cytokines and Metabolic Hormones in Chimpanzees

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Pramod Nehete

2014-01-01

Full Text Available Obesity is characterized by chronic low-grade inflammation and serves as a major risk factor for hypertension, coronary artery disease, dyslipidemias, and type-2 diabetes. The purpose of this study was to examine changes in metabolic hormones, inflammatory cytokines, and immune function, in lean, overweight, and obese chimpanzees in a controlled environment. We observed increased plasma circulating levels of proinflammatory TH-1 cytokines, Interferon gamma, interleukin-6, interleukin-12p40, tumor necrosis factor, soluble CD40 ligand, and Interleukin-1β and anti-inflammatory TH-2 cytokines, Interleukin-4, Interleukin-RA, Interleukin-10, and Interleukin-13 in overweight and obese chimpanzees. We also observed increased levels of metabolic hormones glucagon-like-peptide-1, glucagon, connecting peptide, insulin, pancreatic peptide YY3–36, and leptin in the plasma of overweight and obese chimpanzees. Chemokine, eotaxin, fractalkine, and monocyte chemoattractant protein-1 were higher in lean compared to obese chimpanzees, while chemokine ligand 8 increased in plasma of obese chimpanzees. We also observed an obesity-related effect on immune function as demonstrated by lower mitogen induced proliferation, and natural killer activity and higher production of IFN-γ by PBMC in Elispot assay, These findings suggest that lean, overweight, and obese chimpanzees share circulating inflammatory cytokines and metabolic hormone levels with humans and that chimpanzees can serve as a useful animal model for human studies.

Serum Testosterone Levels in Prostate Cancer Patients Undergoing Luteinizing Hormone-Releasing Hormone Agonist Therapy.

Science.gov (United States)

Morote, Juan; Comas, Inma; Planas, Jacques; Maldonado, Xavier; Celma, Ana; Placer, José; Ferrer, Roser; Carles, Joan; Regis, Lucas

2018-04-01

Serum testosterone measurement is recommended to assess the efficacy of androgen deprivation therapy (ADT) and to diagnose castration resistance in patients with prostate cancer (PCa). Currently, the accepted castrate level of serum testosterone is 50 ng/dL. Liquid chromatography and tandem mass spectrometry (LC MSMS) is the appropriate method to measure testosterone, especially at low levels. However, worldwide, chemiluminescent assays (CLIAs) are used in clinical laboratories, despite their lack of accuracy and reproducibility, because they are automatable, fast, sensitive, and inexpensive. We compared serum testosterone levels measured using LC MSMS and CLIAs in 126 patients with PCa undergoing luteinizing hormone-releasing hormone (LHRH) agonist therapy. The median serum testosterone level was 14.0 ng/dL (range, 2.0-67.0 ng/dL) with LC MSMS and 31.9 ng/dL (range, 10.0-91.6 ng/dL) with CLIA (P  50 ng/dL in 3 patients (2.4%). These ranges were found in 34 (27%), 72 (57.1%), and 20 (15.9%) patients when testosterone was measured using CLIA (P < .001). The castrate level of serum testosterone using LC MSMS and CLIA was 39.8 ng/dL (95% confidence interval [CI], 37.1-43.4 ng/dL) and 66.5 ng/dL (95% CI, 62.3-71.2 ng/dL), respectively. We found that CLIA overestimated the testosterone levels in PCa patients undergoing LHRH agonist therapy. Thus, the castration level was incorrectly considered inadequate with CLIA in almost 15% of patients. The true castration level of serum testosterone using an appropriate method is < 50 ng/dL. Copyright © 2017 Elsevier Inc. All rights reserved.

Synthesis and binding affinity of an iodinated juvenile hormone

Energy Technology Data Exchange (ETDEWEB)

Prestwich, G.D.; Eng, W.S.; Robles, S.; Vogt, R.G.; Wisniewski, J.R.; Wawrzenczyk, C.

1988-01-25

The synthesis of the first iodinated juvenile hormone (JH) in enantiomerically enriched form is reported. This chiral compound, 12-iodo-JH I, has an iodine atom replacing a methyl group of the natural insect juvenile hormone, JH I, which is important in regulating morphogenesis and reproduction in the Lepidoptera. The unlabeled compound shows approximately 10% of the relative binding affinity for the larval hemolymph JH binding protein (JHBP) of Manduca sexta, which specifically binds natural /sup 3/H-10R,11S-JH I (labeled at 58 Ci/mmol) with a KD of 8 X 10(-8) M. It is also approximately one-tenth as biologically active as JH I in the black Manduca and epidermal commitment assays. The 12-hydroxy and 12-oxo compounds are poor competitors and are also biologically inactive. The radioiodinated (/sup 125/I)12-iodo-JH I can be prepared in low yield at greater than 2500 Ci/mmol by nucleophilic displacement using no-carrier-added /sup 125/I-labeled sodium iodide in acetone; however, synthesis using sodium iodide carrier to give the approximately 50 Ci/mmol radioiodinated ligand proceeds in higher radiochemical yield with fewer by-products and provides a radioligand which is more readily handled in binding assays. The KD of (/sup 125/I)12-iodo-JH I was determined for hemolymph JHBP of three insects: M. sexta, 795 nM; Galleria mellonella, 47 nM; Locusta migratoria, 77 nM. The selectivity of 12-iodo-JH I for the 32-kDa JHBP of M. sexta was demonstrated by direct autoradiography of a native polyacrylamide gel electrophoresis gel of larval hemolymph incubated with the radioiodinated ligand. Thus, the in vitro and in vivo activity of 12-iodo-JH I indicate that it can serve as an important new gamma-emitting probe in the search for JH receptor proteins in target tissues.

Heart, lipids and hormones

Directory of Open Access Journals (Sweden)

Peter Wolf

2017-05-01

Full Text Available Cardiovascular disease is the leading cause of death in general population. Besides well-known risk factors such as hypertension, impaired glucose tolerance and dyslipidemia, growing evidence suggests that hormonal changes in various endocrine diseases also impact the cardiac morphology and function. Recent studies highlight the importance of ectopic intracellular myocardial and pericardial lipid deposition, since even slight changes of these fat depots are associated with alterations in cardiac performance. In this review, we overview the effects of hormones, including insulin, thyroid hormones, growth hormone and cortisol, on heart function, focusing on their impact on myocardial lipid metabolism, cardiac substrate utilization and ectopic lipid deposition, in order to highlight the important role of even subtle hormonal changes for heart function in various endocrine and metabolic diseases.

Mining Chemical Activity Status from High-Throughput Screening Assays

KAUST Repository

Soufan, Othman; Ba Alawi, Wail; Afeef, Moataz A.; Essack, Magbubah; Rodionov, Valentin; Kalnis, Panos; Bajic, Vladimir B.

2015-01-01

High-throughput screening (HTS) experiments provide a valuable resource that reports biological activity of numerous chemical compounds relative to their molecular targets. Building computational models that accurately predict such activity status (active vs. inactive) in specific assays is a challenging task given the large volume of data and frequently small proportion of active compounds relative to the inactive ones. We developed a method, DRAMOTE, to predict activity status of chemical compounds in HTP activity assays. For a class of HTP assays, our method achieves considerably better results than the current state-of-the-art-solutions. We achieved this by modification of a minority oversampling technique. To demonstrate that DRAMOTE is performing better than the other methods, we performed a comprehensive comparison analysis with several other methods and evaluated them on data from 11 PubChem assays through 1,350 experiments that involved approximately 500,000 interactions between chemicals and their target proteins. As an example of potential use, we applied DRAMOTE to develop robust models for predicting FDA approved drugs that have high probability to interact with the thyroid stimulating hormone receptor (TSHR) in humans. Our findings are further partially and indirectly supported by 3D docking results and literature information. The results based on approximately 500,000 interactions suggest that DRAMOTE has performed the best and that it can be used for developing robust virtual screening models. The datasets and implementation of all solutions are available as a MATLAB toolbox online at www.cbrc.kaust.edu.sa/dramote and can be found on Figshare.

Mining Chemical Activity Status from High-Throughput Screening Assays

KAUST Repository

Soufan, Othman

2015-12-14

High-throughput screening (HTS) experiments provide a valuable resource that reports biological activity of numerous chemical compounds relative to their molecular targets. Building computational models that accurately predict such activity status (active vs. inactive) in specific assays is a challenging task given the large volume of data and frequently small proportion of active compounds relative to the inactive ones. We developed a method, DRAMOTE, to predict activity status of chemical compounds in HTP activity assays. For a class of HTP assays, our method achieves considerably better results than the current state-of-the-art-solutions. We achieved this by modification of a minority oversampling technique. To demonstrate that DRAMOTE is performing better than the other methods, we performed a comprehensive comparison analysis with several other methods and evaluated them on data from 11 PubChem assays through 1,350 experiments that involved approximately 500,000 interactions between chemicals and their target proteins. As an example of potential use, we applied DRAMOTE to develop robust models for predicting FDA approved drugs that have high probability to interact with the thyroid stimulating hormone receptor (TSHR) in humans. Our findings are further partially and indirectly supported by 3D docking results and literature information. The results based on approximately 500,000 interactions suggest that DRAMOTE has performed the best and that it can be used for developing robust virtual screening models. The datasets and implementation of all solutions are available as a MATLAB toolbox online at www.cbrc.kaust.edu.sa/dramote and can be found on Figshare.

Clinical significance and changes of TRAb and TSI assay in patients with Graves' disease

International Nuclear Information System (INIS)

Hu Xiaolin; Zhang Haiyan

2006-01-01

Objective: To explore the changes and clinical significance of TRAb and TSI detection in patients with Graves' disease. Methods: Serum TRAb and TSI levels were detected by enzyme-linked immunosorbent assay, and thyroid hormone levels were detected by microparticle enzyme immunoassay, including normal controls, Graves' disease in period of onset, catabsis group and hashimotos thyroiditis group. Results: The positive rate of TRAb and TSI in Graves' in period of onset group is 86.67% and 95.0%, TGA and TMA in hashimotos thyroiditis group is 85.29% and 91.18%, respectively. More importantly these results were significant difference than normal controls. Conclusions: It's very important for Graves' disease patients to detect TRAb, TSI, TGA, TMA and thyroid hormone simulta-neously, especially to the curative effect and prognosis criterin in patients with Graves' disease and antidi-astole in patients with hashimotos thyroiditis. (authors)

Thyroid hormone regulates the expression of the sonic hedgehog signaling pathway in the embryonic and adult Mammalian brain.

Science.gov (United States)

Desouza, Lynette A; Sathanoori, Malini; Kapoor, Richa; Rajadhyaksha, Neha; Gonzalez, Luis E; Kottmann, Andreas H; Tole, Shubha; Vaidya, Vidita A

2011-05-01

Thyroid hormone is important for development and plasticity in the immature and adult mammalian brain. Several thyroid hormone-responsive genes are regulated during specific developmental time windows, with relatively few influenced across the lifespan. We provide novel evidence that thyroid hormone regulates expression of the key developmental morphogen sonic hedgehog (Shh), and its coreceptors patched (Ptc) and smoothened (Smo), in the early embryonic and adult forebrain. Maternal hypo- and hyperthyroidism bidirectionally influenced Shh mRNA in embryonic forebrain signaling centers at stages before fetal thyroid hormone synthesis. Further, Smo and Ptc expression were significantly decreased in the forebrain of embryos derived from hypothyroid dams. Adult-onset thyroid hormone perturbations also regulated expression of the Shh pathway bidirectionally, with a significant induction of Shh, Ptc, and Smo after hyperthyroidism and a decline in Smo expression in the hypothyroid brain. Short-term T₃ administration resulted in a significant induction of cortical Shh mRNA expression and also enhanced reporter gene expression in Shh(+/LacZ) mice. Further, acute T₃ treatment of cortical neuronal cultures resulted in a rapid and significant increase in Shh mRNA, suggesting direct effects. Chromatin immunoprecipitation assays performed on adult neocortex indicated enhanced histone acetylation at the Shh promoter after acute T₃ administration, providing further support that Shh is a thyroid hormone-responsive gene. Our results indicate that maternal and adult-onset perturbations of euthyroid status cause robust and region-specific changes in the Shh pathway in the embryonic and adult forebrain, implicating Shh as a possible mechanistic link for specific neurodevelopmental effects of thyroid hormone.

Microculture tetrazolium assays: a comparison between two new tetrazolium salts, XTT and MTS.

Science.gov (United States)

Goodwin, C J; Holt, S J; Downes, S; Marshall, N J

1995-02-13

Microculture tetrazolium assays are being widely exploited to investigate the mechanisms of both cell activation and cell damage. They are colorimetric assays which are based upon the bioreduction of a tetrazolium salt to an intensely coloured formazan. We contrast the responses obtainable with two new tetrazolium salts, MTS and XTT, when used on the rat lymphoma cell line (Nb2 cells), which has been activated by human growth hormone. These tetrazolium salts, unlike the more commonly used MTT, form soluble formazans upon bioreduction by the activated cells. This has the advantage that it eliminates the error-prone solubilisation step which is required for the microculture tetrazolium assays which employ MTT. Bioreduction of XTT and MTS usually requires addition of an intermediate electron acceptor, phenazine methosulphate (PMS). We found that the XTT/PMS, but not the MTS/PMS, reagent mixture was unstable. Nucleation and crystal formation in the XTT/PMS reagent mixture, prepared in DPBS, could occur within 1-3 min. This resulted in a decline in XTT-formazan production and manifested itself in the microculture tetrazolium assay as both poor within-assay precision and serious assay drift. Several features of the system suggested that the formation of charge-transfer complexes between XTT and PMS accounted for this instability. No such instability was encountered when MTS and PMS were mixed. We demonstrate that MTS/PMS provides microculture tetrazolium assays for hGH which are free from these serious artefacts and which are uniquely precise. In conclusion we therefore advocate the use of MTS in preference to XTT for the new generation of microculture tetrazolium assays.

A nonpeptidyl growth hormone secretagogue.

Science.gov (United States)

Smith, R G; Cheng, K; Schoen, W R; Pong, S S; Hickey, G; Jacks, T; Butler, B; Chan, W W; Chaung, L Y; Judith, F

1993-06-11

A nonpeptidyl secretagogue for growth hormone of the structure 3-amino-3-methyl-N-(2,3,4,5-tetrahydro-2-oxo-1-([2'-(1H-tetrazol-5 -yl) (1,1'-biphenyl)-4-yl]methyl)-1H-1-benzazepin-3(R)-yl)-butanamid e (L-692,429) has been identified. L-692,429 synergizes with the natural growth hormone secretagogue growth hormone-releasing hormone and acts through an alternative signal transduction pathway. The mechanism of action of L-692,429 and studies with peptidyl and nonpeptidyl antagonists suggest that this molecule is a mimic of the growth hormone-releasing hexapeptide His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 (GHRP-6). L-692,429 is an example of a nonpeptidyl specific secretagogue for growth hormone.

[Integration of pharmacokinetics and pharmacodynamics based on the in vivo analysis of drug-receptor binding].

Science.gov (United States)

Yamada, Shizuo

2015-01-01

  As I was deeply interested in the effects of drugs on the human body, I chose pharmacology as the subject of special study when I became a 4th year student at Shizuoka College of Pharmacy. I studied abroad as a postdoctoral fellow for two years, from 1978, under the tutelage of Professor Henry I. Yamamura (pharmacology) in the College of Medicine at the University of Arizona, USA. He taught me a variety of valuable skills such as the radioreceptor binding assay, which represented the most advanced technology developed in the US at that time. After returning home, I engaged in clarifying receptor abnormalities in pathological conditions, as well as in drug action mechanisms, by making the best use of this radioreceptor binding assay. In 1989, following the founding of the University of Shizuoka, I was invited by Professor Ryohei Kimura to join the Department of Pharmacokinetics. This switch in discipline provided a good opportunity for me to broaden my perspectives in pharmaceutical sciences. I worked on evaluating drug-receptor binding in vivo as a combined index for pharmacokinetics and pharmacological effect manifestation, with the aim of bridging pharmacology and pharmacokinetics. In fact, by focusing on data from in vivo receptor binding, it became possible to clearly rationalize the important consideration of drug dose-concentration-action relationships, and to study quantitative and kinetic analyses of relationships among pharmacokinetics, receptor binding and pharmacological effects. Based on this concept, I was able to demonstrate the utility of dynamic analyses of drug-receptor binding in drug discovery, drug fostering, and the proper use of pharmacokinetics with regard to many drugs.

Concomitant alteration in number and affinity of P2X and muscarinic receptors are associated with bladder dysfunction in early stage of diabetic rats.

Science.gov (United States)

Yoshizawa, Tsuyoshi; Hayashi, Yukio; Yoshida, Akira; Yoshida, Shohei; Ito, Yoshihiko; Yamaguchi, Kenya; Yamada, Shizuo; Takahashi, Satoru

2018-03-01

To investigate time course of bladder dysfunction and concurrent changes in number and affinity of the muscarinic and P 2 X receptor in the early stage of streptozotocin (STZ)-induced diabetic rats. Diabetic rats were prepared by the intraperitoneal injection of 50 mg/kg of STZ to 7-week-old female Wistar rats. We performed recording of 24-h voiding behavior and cystometry at 1, 4, 8, and 12 weeks after the induction of diabetes. A muscle strip experiments with electrical field stimulation (EFS), carbachol, and α,β-methylene adenosine 5'-triphosphate (α,β-MeATP) were also performed at the same time-points. Additionally, concurrent changes in number and affinity of bladder muscarinic and P 2 X receptor were measured by a radioreceptor assay using [N-methyl- 3 H] scopolamine methyl chloride ([ 3 H]NMS) and α,β-methylene-ATP (2,8- 3 H) tetrasodium salt ([ 3 H]α,β-MeATP). In STZ-induced diabetic rats, polydipsic polyuric pollakiuria were noted on recording of 24-h voiding behavior from early stage. Also, the residual urine volume markedly increased in diabetic rats on cystometry. In the muscle strip experiment, the detrusor contractions induced by EFS, carbachol, and α,β-MeATP were enhanced in STZ-induced diabetic rats. Based on the radioreceptor assay, the maximum number of sites (Bmax) for the specific binding of [ 3 H]NMS and [ 3 H]α,β-MeATP was concurrently increased in the bladder from diabetic rats. Increased bladder contractility is found in early stage of diabetic rats. Then, bladder dysfunction is associated with increased number of muscarinic and P 2 X receptors in STZ-induced diabetic rats.

Corticotropin-releasing hormone and pituitary-adrenal hormones in pregnancies complicated by chronic hypertension.

Science.gov (United States)

Warren, W B; Gurewitsch, E D; Goland, R S

1995-02-01

We hypothesized that maternal plasma corticotropin-releasing hormone levels are elevated in chronic hypertension and that elevations modulate maternal and fetal pituitary-adrenal function. Venous blood samples and 24-hour urine specimens were obtained in normal and hypertensive pregnancies at 21 to 40 weeks of gestation. Corticotropin-releasing hormone, corticotropin, cortisol, dehydroepiandrosterone sulfate, and total estriol levels were measured by radioimmunoassay. Mean hormone levels were compared by unpaired t test or two-way analysis of variance. Plasma corticotropin-releasing hormone levels were elevated early in hypertensive pregnancies but did not increase after 36 weeks. Levels of pituitary and adrenal hormones were not different in normal and hypertensive women. However, maternal plasma estriol levels were lower in hypertensive pregnancies compared with normal pregnancies. Fetal 16-hydroxy dehydroepiandrosterone sulfate, the major precursor to placental estriol production, has been reported to be lower than normal in hypertensive pregnancies, possibly explaining the decreased plasma estriol levels reported here. Early stimulation of placental corticotropin-releasing hormone production or secretion may be related to accelerated maturation of placental endocrine function in pregnancies complicated by chronic hypertension.

Competitive-IgY- Enzyme Linked Immuno Sorbent Assay (CIgY-ELISA to detect the cytokinins in Gerbera jamesonii plantlets

Directory of Open Access Journals (Sweden)

Cleiton Mateus Sousa

2011-08-01

Full Text Available A competitive hyper-immune yolk Immunoglobulin Y - Enzyme Linked Immune Sorbent Assay (CIgY-ELISA, was developed as an alternative method to detect zeatin and 2ip in plantlets of gerbera. The endogenous level of hormones in the plantlets in vitro of gerbera with one or six weeks after replication was determined with competitive IgY-ELISA set to detect between 1 and 100 pmoles of plant hormone for each 1.0 g tissue. The plantlets of six weeks presented sprouts and root, while the plantlets of one week presented only sprouts. The CIgY-ELISA was set with high independent variables values of sensitivity/specificity of 96/89 % for zeatin and 94/78 % for 2ip, with high values of reproducibility (up to 90 % for both the cytokinins. Zeatin content varied from 2.2 to 2.8 pmoles.g-1 and from 2.7 to 3.3 pmoles.g-1 on the plantlet with one and six weeks, respectively. The 2ip content did not vary and was detected near the detection limit in all the assays. It was concluded that the observed capabilities of CIgY-ELISA were putative and the competitive assay was a highly robust and stable method, which could be used for the studies on plant physiology for endogenous cytokinins.

Thyroid Hormone Receptor Mutations in Cancer and Resistance to Thyroid Hormone: Perspective and Prognosis

Directory of Open Access Journals (Sweden)

Meghan D. Rosen

2011-01-01

Full Text Available Thyroid hormone, operating through its receptors, plays crucial roles in the control of normal human physiology and development; deviations from the norm can give rise to disease. Clinical endocrinologists often must confront and correct the consequences of inappropriately high or low thyroid hormone synthesis. Although more rare, disruptions in thyroid hormone endocrinology due to aberrations in the receptor also have severe medical consequences. This review will focus on the afflictions that are caused by, or are closely associated with, mutated thyroid hormone receptors. These include Resistance to Thyroid Hormone Syndrome, erythroleukemia, hepatocellular carcinoma, renal clear cell carcinoma, and thyroid cancer. We will describe current views on the molecular bases of these diseases, and what distinguishes the neoplastic from the non-neoplastic. We will also touch on studies that implicate alterations in receptor expression, and thyroid hormone levels, in certain oncogenic processes.

Radioimmunoassay of polypeptide hormones and enzymes

International Nuclear Information System (INIS)

Felber, J.P.

1974-01-01

General principles of radioimmunoassay are reviewed. Detailed procedures are reviewed for the following hormones: insulin, pituitary hormones, gonadotropins, parathyroid hormone, ACTH, glucagon, gastrin, and peptide hormones. Radioimmunoassay of enzymes is also discussed. (U.S.)

Aging changes in hormone production

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/004000.htm Aging changes in hormone production To use the sharing ... that produce hormones are controlled by other hormones. Aging also changes this process. For example, an endocrine ...

Low vitamin D3 and high anti-Müllerian hormone serum levels in the polycystic ovary syndrome (PCOS): Is there a link?

Science.gov (United States)

Cappy, Hélène; Giacobini, Paolo; Pigny, Pascal; Bruyneel, Aude; Leroy-Billiard, Maryse; Dewailly, Didier; Catteau-Jonard, Sophie

2016-10-01

Low vitamin D serum level has been reported in women with polycystic ovary syndrome (PCOS) compared to controls. A few in vitro studies showed that the bioactive form of vitamin D is able to modulate the expression of the anti-Müllerian hormone (AMH) gene. However, in vivo studies failed to demonstrate clearly whether low vitamin D3 serum level is involved in the AMH excess of PCOS. This prospective study evaluates serum vitamin D3 and AMH levels in women with PCOS and in controls, before and after vitamin D supplementation. Among vitamin D deficient patients, 23 patients with PCOS were compared to 27 women with normal ovarian reserve (NOR). The vitamin D deficient patients received a vitamin D supplementation according to the depth of their insufficiency. For the 23 patients with PCOS and the 27 controls, serum AMH assay and serum calciotropic hormone assays [25-hydroxyvitamin D (25[OH]D), 1,25 dihydroxyvitamin D (1,25[OH] 2 D) and parathyroid hormone (PTH)] were performed before and after supplementation. Serum 25(OH)D levels before treatment were statistically lower in PCOS women than in NOR patients (Ptreatment was observed neither in PCOS patients nor in NOR patients. In both groups, 25(OH)D serum levels were not related to serum AMH levels, serum 1,25(OH) 2 D and serum PTH levels, before and after treatment. We found no evidence that serum calciotropic hormones are linked to circulating AMH levels, particularly in PCOS. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The "multiple hormone deficiency" theory of aging: is human senescence caused mainly by multiple hormone deficiencies?

Science.gov (United States)

Hertoghe, T

2005-12-01

In the human body, the productions, levels and cell receptors of most hormones progressively decline with age, gradually putting the body into various states of endocrine deficiency. The circadian cycles of these hormones also change, sometimes profoundly, with time. In aging individuals, the well-balanced endocrine system can fall into a chaotic condition with losses, phase-advancements, phase delays, unpredictable irregularities of nycthemeral hormone cycles, in particular in very old or sick individuals. The desynchronization makes hormone activities peak at the wrong times and become inefficient, and in certain cases health threatening. The occurrence of multiple hormone deficits and spilling through desynchronization may constitute the major causes of human senescence, and they are treatable causes. Several arguments can be put forward to support the view that senescence is mainly a multiple hormone deficiency syndrome: First, many if not most of the signs, symptoms and diseases (including cardiovascular diseases, cancer, obesity, diabetes, osteoporosis, dementia) of senescence are similar to physical consequences of hormone deficiencies and may be caused by hormone deficiencies. Second, most of the presumed causes of senescence such as excessive free radical formation, glycation, cross-linking of proteins, imbalanced apoptosis system, accumulation of waste products, failure of repair systems, deficient immune system, may be caused or favored by hormone deficiencies. Even genetic causes such as limits to cell proliferation (such as the Hayflick limit of cell division), poor gene polymorphisms, premature telomere shortening and activation of possible genetic "dead programs" may have links with hormone deficiencies, being either the consequence, the cause, or the major favoring factor of hormone deficiencies. Third, well-dosed and -balanced hormone supplements may slow down or stop the progression of signs, symptoms, or diseases of senescence and may often

Kinetics of thyroid hormones

International Nuclear Information System (INIS)

Inada, Mitsuo; Nishikawa, Mitsushige; Naito, Kimikazu; Ishii, Hitoshi; Tanaka, Kiyoshi

1980-01-01

Kinetics of thyroid hormones were outlined, and recent progress in metabolism of these hormones was also described. Recently, not only T 4 and T 3 but also rT 3 , 3,3'-T 2 , 3',5'-T 2 , and 3,5-T 2 can be measured by RIA. To clarify metabolic pathways of these hormones, metabolic clearance rate and production rate of these hormones were calculated. As single-compartment analysis was insufficient to clarify disappearance curves of thyroid hormones in blood such as T 3 and T 2 of which metabolic speed was so fast, multi-compartment analysis or non-compartment analysis were also performed. Thyroid hormones seemed to be measured more precisely by constant infusion method. At the first step of T 4 metabolism, T 3 was formed by 5'-monodeiodination of T 4 , and rT 3 was formed by 5-monodeiodination of T 4 . As metabolic pathways of T 3 and rT 3 , conversion of them to 3,3'-T 2 or to 3',5'-T 2 and 3,5-T 2 was supposed. This subject will be an interesting research theme in future. (Tsunoda, M.)

Comparison of Intact PTH and Bio-Intact PTH Assays Among Non-Dialysis Dependent Chronic Kidney Disease Patients.

Science.gov (United States)

Einbinder, Yael; Benchetrit, Sydney; Golan, Eliezer; Zitman-Gal, Tali

2017-09-01

The third-generation bio-intact parathyroid hormone (PTH) (1-84) assay was designed to overcome problems associated with the detection of C-terminal fragments by the second-generation intact PTH assay. The two assays have been compared primarily among dialysis populations. The present study evaluated the correlations and differences between these two PTH assays among patients with chronic kidney disease (CKD) stages 3 to 5 not yet on dialysis. Blood samples were collected from 98 patients with CKD stages 3 to 5. PTH concentrations were measured simultaneously by using the second-generation - PTH intact-STAT and third-generation bio-intact 1-84 PTH assays. Other serum biomarkers of bone mineral disorders were also assessed. CKD stage was calculated by using the CKD-Epidemiology Collaboration (EPI) formula. Serum bio-intact PTH concentrations were strongly correlated but significantly lower than the intact PTH concentrations (r=0.963, Pbio-intact PTH) positively correlated with urea (r=0.523, r=0.504; P=0.002, respectively), phosphorus (r=0.532, r=0.521; Pbio-intact PTH assay detected significantly lower PTH concentrations compared with intact PTH assay. Additional studies that correlate the diagnosis and management of CKD mineral and bone disorders with bone histomorphometric findings are needed to determine whether bio-intact PTH assay results are better surrogate markers in these early stages of CKD. © The Korean Society for Laboratory Medicine

Production of non-stimulatory immunoglobulins that inhibit TSH binding in Graves' disease after radioiodine administration

International Nuclear Information System (INIS)

Bech, K.; Bliddal, H.; Siersbaek-Nielsen, K.; Friis, T.

1982-01-01

The effect of single dose of 131 I upon thyroid stimulating immunoglobulins has been studied in twenty-two patients with Graves' disease. The thyroid stimulating immunoglobulins were assessed by parallel measurements of thyrotrophin receptor binding inhibitory immunoglobulins (TBII) and of thyroid adenylate cyclase stimulating immunoglobulins (TACSI) in serum by radioreceptor assay and stimulation of adenylate cyclase respectively. The present study thus confirms that radioiodine therapy is followed by an increase of TBII and TACSI in most patients with Graves' disease. The level of TBII can probably provide a marker for development of hypothyroidism following 131 I therapy and might be involved in its pathogenesis. (author)

Low prevalence of antibodies and other plasma factors binding to CC chemokines and IL-2 in HIV-positive patients

DEFF Research Database (Denmark)

Meyer, C N; Svenson, M; Schade Larsen, C

2000-01-01

of HIV-infected patients were therefore assessed by radioimmunoassay and radioreceptor assay. IgG from 4/505 HIV patients and 9/2000 healthy controls (p>0.05) bound rMIP-1alpha and rMIP-1beta, but not rRANTES. No other plasma factors bound the chemokines. The antibodies inhibited receptor binding of both...... chemokines. There was no association between presence of antibodies and disease stage or HIV progression rate. Three of 11 patients treated with rIL-2 developed IgG antibodies suppressing cellular binding and growth promotion of rIL-2. Hence, circulating factors, including antibodies MIP-1alpha/MIP-1beta...

Plants altering hormonal milieu: A review

Directory of Open Access Journals (Sweden)

Prashant Tiwari

2017-02-01

Full Text Available The aim of the present review article is to investigate the herbs which can alter the levels of hormones like Follicle stimulating hormone, Prolactin, Growth hormone, Insulin, Thyroxine, Estrogen, Progesterone, Testosterone, and Relaxin etc. Hormones are chemical signal agents produced by different endocrine glands for regulating our biological functions. The glands like pituitary, thyroid, adrenal, ovaries in women and testes in men all secrete a number of hormones with different actions. However, when these hormones are perfectly balanced then people become healthy and fit. But several factors like pathophysiological as well as biochemical changes, disease conditions, changes in the atmosphere, changes in the body, diet changes etc. may result in imbalance of various hormones that produce undesirable symptoms and disorders. As medicinal plants have their importance since ancient time, people have been using it in various ways as a source of medicine for regulation of hormonal imbalance. Moreover, it is observed that certain herbs have a balancing effect on hormones and have great impact on well-being of the people. So, considering these facts we expect that the article provides an overview on medicinal plants with potential of altering hormone level.

Plants altering hormonal milieu: A review

Directory of Open Access Journals (Sweden)

Prashant Tiwari

2017-01-01

Full Text Available The aim of the present review article is to investigate the herbs which can alter the levels of hormones like Follicle stimulating hormone, Prolactin, Growth hormone, Insulin, Thyroxine, Estrogen, Progesterone, Testosterone, and Relaxin etc. Hormones are chemical signal agents produced by different endocrine glands for regulating our biological functions. The glands like pituitary, thyroid, adrenal, ovaries in women and testes in men all secrete a number of hormones with different actions. However, when these hormones are perfectly balanced then people become healthy and fit. But several factors like pathophysiological as well as biochemical changes, disease conditions, changes in the atmosphere, changes in the body, diet changes etc. may result in imbalance of various hormones that produce undesirable symptoms and disorders. As medicinal plants have their importance since ancient time, people have been using it in various ways as a source of medicine for regulation of hormonal imbalance. Moreover, it is observed that certain herbs have a balancing effect on hormones and have great impact on well-being of the people. So, considering these facts we expect that the article provides an overview on medicinal plants with potential of altering hormone level.

Thyroid Hormone, Cancer, and Apoptosis.

Science.gov (United States)

Lin, Hung-Yun; Chin, Yu-Tan; Yang, Yu-Chen S H; Lai, Husan-Yu; Wang-Peng, Jacqueline; Liu, Leory F; Tang, Heng-Yuan; Davis, Paul J

2016-06-13

Thyroid hormones play important roles in regulating normal metabolism, development, and growth. They also stimulate cancer cell proliferation. Their metabolic and developmental effects and growth effects in normal tissues are mediated primarily by nuclear hormone receptors. A cell surface receptor for the hormone on integrin [alpha]vβ3 is the initiation site for effects on tumor cells. Clinical hypothyroidism may retard cancer growth, and hyperthyroidism was recently linked to the prevalence of certain cancers. Local levels of thyroid hormones are controlled through activation and deactivation of iodothyronine deiodinases in different organs. The relative activities of different deiodinases that exist in tissues or organs also affect the progression and development of specific types of cancers. In this review, the effects of thyroid hormone on signaling pathways in breast, brain, liver, thyroid, and colon cancers are discussed. The importance of nuclear thyroid hormone receptor isoforms and of the hormone receptor on the extracellular domain of integrin [alpha]vβ3 as potential cancer risk factors and therapeutic targets are addressed. We analyze the intracellular signaling pathways activated by thyroid hormones in cancer progression in hyperthyroidism or at physiological concentrations in the euthyroid state. Determining how to utilize the deaminated thyroid hormone analog (tetrac), and its nanoparticulate derivative to reduce risks of cancer progression, enhance therapeutic outcomes, and prevent cancer recurrence is also deliberated. © 2016 American Physiological Society. Compr Physiol 6:1221-1237, 2016. Copyright © 2016 John Wiley & Sons, Inc.

Short Communication: Comparison of Maxim and Sedia Limiting Antigen Assay Performance for Measuring HIV Incidence.

Science.gov (United States)

Schlusser, Katherine E; Konikoff, Jacob; Kirkpatrick, Allison R; Morrison, Charles; Chipato, Tsungai; Chen, Pai-Lien; Munjoma, Marshall; Eshleman, Susan H; Laeyendecker, Oliver

2017-06-01

Accurate methods for cross-sectional incidence estimation are needed for HIV prevention research. The Limiting Antigen Avidity (LAg-Avidity) assay has been marketed by two vendors, Maxim Biomedical and Sedia BioSciences Corporation. Performance differences between the two versions of the assay are unknown. We tested a total 1,410 treatment-naive samples with both versions of the assay. The samples came from 176 seroconverters from the Zimbabwe Hormonal Contraception and HIV Study. The correlation between the two versions of the assay was 0.93 for the optical density (OD) and 0.86 for the normalized OD. As the difference was more pronounced for the normalized OD, the difference in assays can be attributed to the calibrators. The mean duration of recent infection (MDRI), the average time individuals infected 1,000 copies/ml. The MDRI was 137 days for Sedia and 157 days for Maxim, with a difference of 20 days (95% CI 11-30). The MDRIs decreased to 102 and 120 days with the inclusion of a viral load cutoff of >1,000 copies/ml. These results imply that use of the Sedia LAg-Avidity will result in estimates of incidence ∼13% lower than those using the Maxim LAg-Avidity.

Hormones and the blood-brain barrier.

Science.gov (United States)

Hampl, Richard; Bičíková, Marie; Sosvorová, Lucie

2015-03-01

Hormones exert many actions in the brain, and brain cells are also hormonally active. To reach their targets in brain structures, hormones must overcome the blood-brain barrier (BBB). The BBB is a unique device selecting desired/undesired molecules to reach or leave the brain, and it is composed of endothelial cells forming the brain vasculature. These cells differ from other endothelial cells in their almost impermeable tight junctions and in possessing several membrane structures such as receptors, transporters, and metabolically active molecules, ensuring their selection function. The main ways how compounds pass through the BBB are briefly outlined in this review. The main part concerns the transport of major classes of hormones: steroids, including neurosteroids, thyroid hormones, insulin, and other peptide hormones regulating energy homeostasis, growth hormone, and also various cytokines. Peptide transporters mediating the saturable transport of individual classes of hormones are reviewed. The last paragraph provides examples of how hormones affect the permeability and function of the BBB either at the level of tight junctions or by various transporters.

Hormonal control of euryhalinity

Science.gov (United States)

Takei, Yoshio; McCormick, Stephen D.; McCormick, Stephen D.; Farrell, Anthony Peter; Brauner, Colin J.

2013-01-01

Hormones play a critical role in maintaining body fluid balance in euryhaline fishes during changes in environmental salinity. The neuroendocrine axis senses osmotic and ionic changes, then signals and coordinates tissue-specific responses to regulate water and ion fluxes. Rapid-acting hormones, e.g. angiotensins, cope with immediate challenges by controlling drinking rate and the activity of ion transporters in the gill, gut, and kidney. Slow-acting hormones, e.g. prolactin and growth hormone/insulin-like growth factor-1, reorganize the body for long-term acclimation by altering the abundance of ion transporters and through cell proliferation and differentiation of ionocytes and other osmoregulatory cells. Euryhaline species exist in all groups of fish, including cyclostomes, and cartilaginous and teleost fishes. The diverse strategies for responding to changes in salinity have led to differential regulation and tissue-specific effects of hormones. Combining traditional physiological approaches with genomic, transcriptomic, and proteomic analyses will elucidate the patterns and diversity of the endocrine control of euryhalinity.

Mass spectrometry and immunoassay: how to measure steroid hormones today and tomorrow.

Science.gov (United States)

Taylor, Angela E; Keevil, Brian; Huhtaniemi, Ilpo T

2015-08-01

The recent onslaught of mass spectrometry (MS) to measurements of steroid hormones, including demands that they should be the only acceptable method, has confused clinicians and scientists who have relied for more than 40 years on a variety of immunoassay (IA) methods in steroid hormone measurements. There is little doubt that MS methods with their superior specificity will be the future method of choice in many clinical and research applications of steroid hormone measurement. However, the majority of steroid measurements are currently, and will continue to be, carried out using various types of IAs for several reasons, including their technical ease, cost and availability of commercial reagents. Speedy replacement of all IAs with MS is an unrealistic and unnecessary goal, because the availability of MS measurements is limited by cost, need of expensive equipment, technical demands and lack of commercial applications. Furthermore, IAs have multiple well-known advantages that vindicate their continuing use. The purpose of this article is to elucidate the advantages and limitations of the MS and IA techniques from two angles, i.e. promotion of MS and defence of IA. The purpose of the text is to give the reader an unbiased view about the current state and future trends of steroid analysis and to help him/her choose the correct assay method to serve his/her diagnostic and research needs. © 2015 European Society of Endocrinology.

Radioactive probes for adrenocorticotropic hormone receptors

International Nuclear Information System (INIS)

Hofmann, K.; Romovacek, H.; Stehle, C.J.; Finn, F.M.; Bothner-By, A.A.; Mishra, P.K.

1986-01-01

Our attempts to develop adrenocorticotropic hormone (ACTH) analogues that can be employed for ACTH receptor identification and isolation began with the synthesis of ACTH fragments containing N epsilon-(dethiobiotinyl)lysine (dethiobiocytin) amide in position 25 to be used for affinity chromatographic purification of hormone-receptor complexes on Sepharose-immobilized avidin resins. Because labeling ACTH or ACTH fragments by conventional iodination techniques destroys biological activity due to oxidation of Met4 and incorporation of iodine into Tyr2, we have prepared [Phe2,Nle4]ACTH1-24, [Phe2,Nle4,biocytin25]ACTH1-25 amide, and [Phe2,Nle4,dethiobiocytin25]ACTH1-25 amide by conventional synthetic techniques. The HPLC profiles and amino acid analyses of the final products indicate that the materials are of a high degree of purity. The amount of tertiary butylation of the Trp residue in the peptides was assessed by NMR and was found to be less than 0.5%. All three peptides are equipotent with the standard ACTH1-24 as concerns their ability to stimulate steroidogenesis and cAMP formation in bovine adrenal cortical cells. Iodination of [Phe2,Nle4]ACTH1-24, with iodogen as the oxidizing agent, has been accomplished without any detectable loss of biological activity. The mono- and diiodo derivatives of [Phe2,Nle4]ACTH1-24 have been prepared, separated by HPLC, and assayed for biological activity. Both peptides have the full capacity to stimulate steroidogenesis and cAMP production in bovine adrenal cortical cells

Comparison of risks due to bisphenol A and radiation with trad-MCN assay

International Nuclear Information System (INIS)

Shin, H. S.; Lee, J. H.; Kim, J. K.; Chon, K. J.; Lee, B. H.

2001-01-01

Many kinds of synthetic chemicals have been being used for various purposes. Some of them are called 'environmental hormones' because they can disturb the endocrine system of organisms. Presently no technique is established for the quantitative assessment of biological risk of the environmental hormones. The pollen mother cells (PMC) of Tradescantia are very sensitive to chemical toxicants or ionizing radiation, and thus can be used as a biological end-point assessing their effect. Micronucleus frequencies in PMC showed a good dose- and concentration-response relationship for radiation and bisphenol A. From the dose-response relationship, it is possible to estimate the equivalent bisphenol A concentration, or vice versa. One μM/ml of bisphenol A is equivalent to 1.8 cGy of radiation in the induction of micronuclei. It is known from the result that Trad-MCN assay can be an excellent tool for detection of biological risk due to environmental toxicants or synthetic chemicals

Application of ovine luteinizing hormone (LH) radioimmunoassay in the quantitation of LH in different mammalian species. [/sup 125/I tracer technique

Energy Technology Data Exchange (ETDEWEB)

Millar, R.P.; Aehnelt, C.

1977-09-01

A sensitive double antibody radioimmunoassay has been developed for measuring luteinizing hormone (LH) in various African mammalian species, using rabbit anti-ovine LH serum (GDN 15) and radioiodinated rat LH or ovine LH. Serum and pituitary homogenates from some African mammals (hyrax, reedbuck, sable, impala, tsessebe, thar, spring-hare, ground squirrel and cheetah, as well as the domestic sheep, cow and horse and laboratory rat and hamster) produced displacement curves parallel to that of the ovine LH standards. The specificity of the assay was examined in detail for one species, the rock hyrax. Radioimmunoassay and bioassay estimates of LH in hyrax pituitaries containing widely differing quantities of pituitary hormones were similar. In sexually active male hyrax mean plasma LH was 12.1 ng/ml and pituitary LH 194 ..mu..g/gland, but in sexually quiescent hyrax mean plasma LH was 2.4 ng/ml and mean pituitary LH 76 ..mu..g/gland. Intravenous injection of 10 ..mu..g of luteinizing hormone releasing hormone increased mean LH levels in hyrax from 0.9 ng/ml to 23.2 ng/ml by 30 min. Conversely, im injection of 250 ..mu..g testosterone induced a fall in LH levels in male hyrax from 1.7 ng/ml to 0.7 ng/ml 6 h after administration. Although the specificity of the assay for quantitating plasma LH in other species was not categorically established, there was a good correlation between plasma LH concentration and reproductive state in the bontebok, impala, spring-hare, thar, cheetah, domestic horse and laboratory rat, suggesting the potential use of the antiserum in quantitating LH in a variety of mammalian species.

Sex hormones affect neurotransmitters and shape the adult female brain during hormonal transition periods

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Claudia eBarth

2015-02-01

Full Text Available Sex hormones have been implicated in neurite outgrowth, synaptogenesis, dendritic branching, myelination and other important mechanisms of neural plasticity. Here we review the evidence from animal experiments and human studies reporting interactions between sex hormones and the dominant neurotransmitters, such as serotonin, dopamine, GABA and glutamate. We provide an overview of accumulating data during physiological and pathological conditions and discuss currently conceptualized theories on how sex hormones potentially trigger neuroplasticity changes through these four neurochemical systems. Many brain regions have been demonstrated to express high densities for estrogen- and progesterone receptors, such as the amygdala, the hypothalamus, and the hippocampus. As the hippocampus is of particular relevance in the context of mediating structural plasticity in the adult brain, we put particular emphasis on what evidence could be gathered thus far that links differences in behavior, neurochemical patterns and hippocampal structure to a changing hormonal environment. Finally, we discuss how physiologically occurring hormonal transition periods in humans can be used to model how changes in sex hormones influence functional connectivity, neurotransmission and brain structure in vivo.

Reproductive toxicity after levetiracetam administration in male rats: Evidence for role of hormonal status and oxidative stress.

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Merve Baysal

Full Text Available Levetiracetam (LEV is an antiepileptic drug commonly used in the treatment of epilepsy because of its excellent safety profile in all age groups. It is remarkable that there are no studies evaluating the toxic effects of this drug on the male reproductive system, as it is commonly used in male patients of reproductive age. From this point of view, our aim was to evaluate the possible toxic effects of LEV on the male reproductive system. Therefore, LEV was administered to male rats orally at 50, 150, and 300 mg/kg for 70 consecutive days. At the end of this period, alterations to body and organ weights were calculated, and sperm concentration, motility, and morphology were investigated by a computer-assisted sperm analysis system. Sperm DNA damage was determined by comet assay and histopathological examination of the testes was carried out. Serum testosterone, follicle-stimulating hormone (FSH, and luteinizing hormone (LH levels were measured by ELISAs to determine the effects of hormonal status, while glutathione, superoxide dismutase, catalase, and malondialdehyde levels in the testes were measured by colorimetric assay kits to determine the role of oxidative status in potential toxicity. According to the results, sperm quality was decreased by LEV treatment in a dose-dependent manner. LEV induced significant DNA damage in the 150 and 300 mg/kg LEV-administered groups. Histopathology of the testes showed that LEV resulted in testicular injury in the 300 mg/kg LEV-administered group. Serum testosterone, FSH, and LH levels were significantly decreased in the 300 mg/kg LEV-administered group. Glutathione, superoxide dismutase, and catalase levels were significantly decreased in all experimental groups while malondialdehyde levels were significantly increased in 150 and 300 mg/kg LEV-administered groups. According to these results, it was determined that LEV administration decreased sperm quality and it was alleged that hormonal alteration and

Parathyroid hormone in sodium-dependent hypertension

International Nuclear Information System (INIS)

Doris, P.A.; Harvey, S.; Pang, P.K.T.

1987-01-01

Plasma parathyroid hormone (pPTH) levels have been assessed in three separate radioimmunoassay systems in samples from Wistar-Kyoto rats. The animals were subjected to one of three dietary regimens throughout the study period: Group 1 animals consumed normal rat chow and drank tap water; Group 2 animals consumed normal rat chow and tap water was replaced with 0.05% saline solution; Group 3 animals consumed normal rat chow to which 2.5% CaCO 3 had been added and also drank 0.5% saline solution. Three assay systems were used to measure pPTH levels from trunk blood samples obtained by guillotine decapitation. One assay used an antiserum directed toward the vasoactive N terminal fragment 1-34 and produced pPTH measurements of 0.74 +/- 0.05 ng/ml in Gp 1 animals, 1.04 +/- 0.07 ng/ml in Gp 2 animals and 1.12 +/- 0.08 ng/ml in Gp 3 animals. This pattern was consistent with that obtained by another antiserum which had been raised against the intact 1-84 PTH molecule and produced values of 0.25 +/- 0.03 ng/ml in Gp 1 animals, 0.55 +/- 0.07 ng/ml in Gp 2 animals and 0.74 +/- 0.04 ng/ml in Gp 3 animals. Antiserum raised against the C-terminal did not show any difference in pPTH across groups. The authors conclude that saline consumption may increase some portions of circulating PTH. 26 references, 2 tables

A common polymorphism of the growth hormone receptor is associated with increased responsiveness to growth hormone.

Science.gov (United States)

Dos Santos, Christine; Essioux, Laurent; Teinturier, Cécile; Tauber, Maïté; Goffin, Vincent; Bougnères, Pierre

2004-07-01

Growth hormone is used to increase height in short children who are not deficient in growth hormone, but its efficacy varies largely across individuals. The genetic factors responsible for this variation are entirely unknown. In two cohorts of short children treated with growth hormone, we found that an isoform of the growth hormone receptor gene that lacks exon 3 (d3-GHR) was associated with 1.7 to 2 times more growth acceleration induced by growth hormone than the full-length isoform (P < 0.0001). In transfection experiments, the transduction of growth hormone signaling through d3-GHR homo- or heterodimers was approximately 30% higher than through full-length GHR homodimers (P < 0.0001). One-half of Europeans are hetero- or homozygous with respect to the allele encoding the d3-GHR isoform, which is dominant over the full-length isoform. These observations suggest that the polymorphism in exon 3 of GHR is important in growth hormone pharmacogenetics.

A Rapid ELISA Method for 17, 20b-dihydroxy-4-pregenen-3-one (17,20bP Hormone Using Acetylcholinesterase Enzyme as Tracer

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M Ebrahimi

2004-06-01

Full Text Available Background: During the past 15 years Enzyme Linked ImmunoSorbent Assay (ELISA has been described as an alternative to radioimmunoassay for steroid detection. In addition to gonads, sperm itself is capable of producing reduced progesterone metabolites. In this study we introduced a method to extend the applicability of previous measures by describing a general preparation procedure for the enzyme label which is applicable to any steroid hormone. Methods: A simple and rapid Enzyme Linked Immunosorbant Assay (ELISA is described and validated for 17,20β- dihydroxy-4-pregnen-3-one (17,20βP. A general procedure for preparation of the acetylcholinesterase labelled steroid is described which is applicable to any steroid. Results: Use of acetylcholinesterase tracer increased the sensitivity of assay so that reliable measurements of each steroid could be achieved with only 10 µl of plasma. ELISA was applied to measure of 17,20βP steroid production by sperm of trout which has sufficient amount of potent and active 20βHSD enzyme to convert 17α-hydroxy-4-pregnen-3-one (17αP substrate to 17,20βP product. The results showed that a clear shift in 17,20βP production was found with increase in substrate concentration in all in vitro incubations. Conclusion: ELISA method presented in this study has greater sensitivity and accuracy compared to previously described method that uses radiolabelled substances. Keywords: Immunoassay, ELISA, Steroids, Hormone, Assay

Interconnection between thyroid hormone signalling pathways and parvovirus cytotoxic functions.

Science.gov (United States)

Vanacker, J M; Laudet, V; Adelmant, G; Stéhelin, D; Rommelaere, J

1993-01-01

Nonstructural (NS) proteins of autonomous parvoviruses can repress expression driven by heterologous promoters, an activity which thus far has not been separated from their cytotoxic effects. It is shown here that, in transient transfection assays, the NS-1 protein of the parvovirus minute virus of mice (MVMp) activates the promoter of the human c-erbA1 gene, encoding the thyroid hormone (T3) receptor alpha. The endogenous c-erbA1 promoter is also a target for induction upon MVMp infection. Moreover, T3 was found to up-modulate the level of cell sensitivity to parvovirus attack. These data suggest an interconnection between T3 signalling and NS cytotoxic pathways. Images PMID:8230488

TGF-beta1 expression in EL4 lymphoma cells overexpressing growth hormone.

Science.gov (United States)

Farmer, John T; Weigent, Douglas A

2006-03-01

Our previous studies show that growth hormone overexpression (GHo) upregulates the expression of the IGF-1R and IGF-2R resulting in the protection of the EL4 lymphoma cell line from apoptosis. In this study, we report that GHo also increases TGF-beta1 protein expression measured by luciferase promoter assay, Western analysis, and ELISA. Further, the data show that antibody to TGF-betaR2 decreases TGF-beta1 promoter activity to the level of vector alone control cells. GHo cells treated with (125)I-rh-latent TGF-beta1 showed increased activation of latent TGF-beta1 as measured by an increase in the active 24kDa, TGF-beta1 compared to vector alone control cells. The ability of endogenous GH to increase TGF-beta1 expression is blocked in EL4 cells by antisense but not sense oligodeoxynucleotides or in cells cultured with antibody to growth hormone (GH). The data suggest that endogenous GH may protect from apoptosis through the IGF-1R receptor while limiting cellular growth through increased expression and activation of TGF-beta1.

BIOTECHNOLOGY OF RECOMBINANT HORMONES IN DOPING

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Biljana Vitošević

2011-09-01

Full Text Available Recombinant DNA technology has allowed rapid progress in creating biosynthetic gene products for the treatment of many diseases. In this way it can produce large amounts of hormone, which is intended for the treatment of many pathological conditions. Recombinant hormones that are commonly used are insulin, growth hormone and erythropoietin. Precisely because of the availability of these recombinant hormones, it started their abuse by athletes. Experiments in animal models confirmed the potential effects of some of these hormones in increasing physical abilities, which attracted the attention of athletes who push the limits of their competitive capability by such manipulation. The risks of the use of recombinant hormones in doping include serious consequences for the health of athletes. Methods of detection of endogenous hormones from recombined based on the use of a monoclonal antibodies, capillary zone electrophoresis and protein biomarkers

Radioisotopic methods of investigation in endocrinology. Radioizotopnye metody issledovaniya v endokrinologii

Energy Technology Data Exchange (ETDEWEB)

Malenchenko, A F; Matveenko, E G; Livshits, I B; Seregin, V V; Spesivtseva, V G

1976-01-01

A description is given of research on iodine metabolism both under normal and pathological conditions employing the method of clinical dynamic radiometry. Possible uses of radioisotopes are indicated for evaluating the function of the parathyroid glands, the pancreas, and the pituitary-adrenal system. Data are given on the practical use of radio-immune, radio-receptor methods as well as the competitive bonding method for determining a number of hormonal and other biologically active metabolites and substances with low antigen activity in various pathological states both clinically and in experiments. The use of neutron-activation methods in biology and medicine is demonstrated. The book is intended for endocrinologists, biologists, and scientific associates interested in the study of the functional state of endocrine glands by radioisotopic methods. 46 figures, 16 tables.

Gastrointestinal hormone research - with a Scandinavian annotation

DEFF Research Database (Denmark)

Rehfeld, Jens F

2015-01-01

Gastrointestinal hormones are peptides released from neuroendocrine cells in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gut, which makes it the largest hormone-producing organ in the body. Modern biology makes it feasible to conceive the hormones...... as a blood-borne hormone, a neurotransmitter, a local growth factor or a fertility factor. The targets of gastrointestinal hormones are specific G-protein-coupled receptors that are expressed in the cell membranes also outside the digestive tract. Thus, gut hormones not only regulate digestive functions...

[Hormones and hair growth].

Science.gov (United States)

Trüeb, R M

2010-06-01

With respect to the relationship between hormones and hair growth, the role of androgens for androgenetic alopecia (AGA) and hirsutism is best acknowledged. Accordingly, therapeutic strategies that intervene in androgen metabolism have been successfully developed for treatment of these conditions. Clinical observations of hair conditions involving hormones beyond the androgen horizon have determined their role in regulation of hair growth: estrogens, prolactin, thyroid hormone, cortisone, growth hormone (GH), and melatonin. Primary GH resistance is characterized by thin hair, while acromegaly may cause hypertrichosis. Hyperprolactinemia may cause hair loss and hirsutism. Partial synchronization of the hair cycle in anagen during late pregnancy points to an estrogen effect, while aromatase inhibitors cause hair loss. Hair loss in a causal relationship to thyroid disorders is well documented. In contrast to AGA, senescent alopecia affects the hair in a diffuse manner. The question arises, whether the hypothesis that a causal relationship exists between the age-related reduction of circulating hormones and organ function also applies to hair and the aging of hair.

Sensitive and rapid immunoassay for parathyroid hormone using magnetic particle labels and magnetic actuation.

Science.gov (United States)

Dittmer, W U; de Kievit, P; Prins, M W J; Vissers, J L M; Mersch, M E C; Martens, M F W C

2008-09-30

A rapid method for the sensitive detection of proteins using actuated magnetic particle labels, which are measured with a giant magneto-resistive (GMR) biosensor, is described. The technique involves a 1-step sandwich immunoassay with no fluid replacement steps. The various assay binding reactions as well as the bound/free separation are entirely controlled by magnetic forces induced by electromagnets above and below the sensor chip. During the assay, particles conjugated with tracer antibodies are actuated through the sample for target capture, and rapidly brought to the sensor surface where they bind to immobilized capture antibodies. Weakly or unbound labels are removed with a magnetic force oriented away from the GMR sensor surface. For the measurement of parathyroid hormone (PTH), a detection limit in the 10 pM range is obtained with a total assay time of 15 min when 300 nm particles are used. The same sensitivity can be achieved in 5 min when 500 nm particles are used. If 500 nm particles are employed in a 15-minute assay, then 0.8 pM of PTH is detectable. The low sample volume, high analytical performance and high speed of the test coupled with the compact GMR biosensor make the system especially suitable for sensitive testing outside of laboratory environments.

Radioreceptor assay for benzodiazepines in biological fluids using a new dry and stable receptor preparation

International Nuclear Information System (INIS)

Lund, J.

1981-01-01

A method for determination of benzodiazepines in human blood, plasma, saliva and urine has been developed. The method is based upon the competition between 3 H-flunitrazepam and biologically active benzodiazepines in biological fluids for brain specific receptors, prepared in a stable, dry form and easy to handle. The pharmacological specificity for benzodiazepines of the dry stable receptor preparation is closely similar to that of fresh membrane-bound rat brain receptors. The method is specific for biologically active benzodiazepines; it is relatively rapid, sensitive and reproducible, and can be performed at room temperature. (author)

Hormonal effects in newborns

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... page: //medlineplus.gov/ency/article/001911.htm Hormonal effects in newborns To use the sharing features on this page, please enable JavaScript. Hormonal effects in newborns occur because in the womb, babies ...

Antidiuretic hormone blood test

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... medlineplus.gov/ency/article/003702.htm Antidiuretic hormone blood test To use the sharing features on this page, please enable JavaScript. Antidiuretic blood test measures the level of antidiuretic hormone (ADH) in ...

New radioimmunoassay for follicle-stimulating hormone in macaques: ovulatory menstrual cycles. [/sup 125/I tracer technique

Energy Technology Data Exchange (ETDEWEB)

Hodgen, G.D.; Wilks, J.W.; Vaitukaitis, J.L.; Chen, H.C.; Papkoff, H.; Ross, G.

1976-07-01

A sensitive and specific radioimmunoassay system for macaque follicle-stimulating hormone (mFSH) was developed utilizing an antiserum (H-31) prepared in a rabbit against purified ovine FSH as the immunogen. Sera from castrated female, adult male, and juvenile rhesus monkeys, as well as urinary extracts from castrated rhesus and bonnet monkeys, were used to demonstrate parallelism with a standard of partially purified monkey pituitary gonadotropins (LER-M-907-D). An extract of baboon pituitary tissue also showed parallelism with the reference standard. A highly purified pituitary extract (WP-X-105-28), containing approximately 75 percent macaque luteinizing hormone (mLH) and 1 percent mFSH, was used to demonstrate the specificity of this mFSH assay system. Sera and urinary extracts obtained from hypophysectomized monkeys did not show cross-reactivity in the assay. Macaque chorionic gonadotropin (mCG) did not produce an inhibition curve in the assay, as determined from serum samples and urinary extracts collected from pregnant monkeys at the time of peak mCG secretion. Serum concentrations of mFSH were suppressed in ovariectomized monkeys by the administration of ethinyl estradiol for 3 days, but returned to near pretreatment values by 96 h after the last estradiol administration. The determination of serum mFSH concentrations in daily blood samples obtained from 20 rhesus monkeys throughout ovulatory menstrual cycles revealed a pattern similar to that previously reported for the rhesus monkey and the woman. The peak value of serum mFSH during the menstrual cycle coincided with the midcycle surge of mLH in each case. The gonadotropin peaks were preceded by increasing serum concentrations of estradiol and followed by rises in the serum concentrations of progesterone.

Does weight loss improve semen quality and reproductive hormones? results from a cohort of severely obese men

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Ernst Emil

2011-08-01

Full Text Available Abstract Background A high body mass index (BMI has been associated with reduced semen quality and male subfecundity, but no studies following obese men losing weight have yet been published. We examined semen quality and reproductive hormones among morbidly obese men and studied if weight loss improved the reproductive indicators. Methods In this pilot cohort study, 43 men with BMI > 33 kg/m2 were followed through a 14 week residential weight loss program. The participants provided semen samples and had blood samples drawn, filled in questionnaires, and had clinical examinations before and after the intervention. Conventional semen characteristics as well as sperm DNA integrity, analysed by the sperm chromatin structure assay (SCSA were obtained. Serum levels of testosterone, estradiol, sex hormone-binding globulin (SHBG, luteinizing hormone (LH, follicle-stimulating hormone (FSH, anti-Müllerian hormone (AMH and inhibin B (Inh-B were measured. Results Participants were from 20 to 59 years of age (median = 32 with BMI ranging from 33 to 61 kg/m2. At baseline, after adjustment for potential confounders, BMI was inversely associated with sperm concentration (p = 0.02, total sperm count (p = 0.02, sperm morphology (p = 0.04, and motile sperm (p = 0.005 as well as testosterone (p = 0.04 and Inh-B (p = 0.04 and positively associated to estradiol (p Conclusion This study found obesity to be associated with poor semen quality and altered reproductive hormonal profile. Weight loss may potentially lead to improvement in semen quality. Whether the improvement is a result of the reduction in body weight per se or improved lifestyles remains unknown.

Effects of Growth Hormone Replacement Therapy on Bone Mineral Density in Growth Hormone Deficient Adults: A Meta-Analysis

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Peng Xue

2013-01-01

Full Text Available Objectives. Growth hormone deficiency patients exhibited reduced bone mineral density compared with healthy controls, but previous researches demonstrated uncertainty about the effect of growth hormone replacement therapy on bone in growth hormone deficient adults. The aim of this study was to determine whether the growth hormone replacement therapy could elevate bone mineral density in growth hormone deficient adults. Methods. In this meta-analysis, searches of Medline, Embase, and The Cochrane Library were undertaken to identify studies in humans of the association between growth hormone treatment and bone mineral density in growth hormone deficient adults. Random effects model was used for this meta-analysis. Results. A total of 20 studies (including one outlier study with 936 subjects were included in our research. We detected significant overall association of growth hormone treatment with increased bone mineral density of spine, femoral neck, and total body, but some results of subgroup analyses were not consistent with the overall analyses. Conclusions. Our meta-analysis suggested that growth hormone replacement therapy could have beneficial influence on bone mineral density in growth hormone deficient adults, but, in some subject populations, the influence was not evident.

The study in the relationship between serum calcium and serum parathyroid hormone (PTH) by employing the various kits of PTH assay

International Nuclear Information System (INIS)

Torizumi, Kazutami; Aibata, Hirofumi; Taniguchi, Yoshiyuki; Kiji, Shigeyuki; Ueyoshi, Akitaka; Shimizu, Eiji; Okamoto, Yukiharu; Tuda, Tadaaki; Ota, Kiichiro

1987-01-01

In order to evaluate the influences of serum PTH assay in the various concentrations of serum calcium, we divided into three groups which serum calcium had below 8.0 mg/dl, 8.2 mg/dl to 9.8 mg/dl and above 10.0 mg/dl at random samples and assayed PTH in serum sample, using various kits of PTH assay obtained from commercial sources. Our results suggested that the measurement of serum PTH influenced by the concentration of serum calcium and therefore, should be taken an attention of serum calcium in each sample. (author)

Growth hormone stimulation test

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... this page: //medlineplus.gov/ency/article/003377.htm Growth hormone stimulation test To use the sharing features on this page, please enable JavaScript. The growth hormone (GH) stimulation test measures the ability of ...

SOCS2 mediates the cross talk between androgen and growth hormone signaling in prostate cancer

DEFF Research Database (Denmark)

Iglesias Gato, Diego; Chuan, Yin Choy; Wikström, Pernilla

2014-01-01

) as mediator of the cross talk between androgens and GH signals in the prostate and its potential role as tumor suppressor in prostate cancer (PCa). We observed that SOCS2 protein levels assayed by immunohistochemistry are elevated in hormone therapy-naive localized prostatic adenocarcinoma in comparison...... of transcription 5 protein (STAT5) and androgen receptor-dependent transcription. Consequentially, SOCS2 inhibits GH activation of Janus kinase 2, Src and STAT5 as well as both cell invasion and cell proliferation in vitro. In vivo, SOCS2 limits proliferation and production of IGF-1 in the prostate in response......Anabolic signals such as androgens and the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis play an essential role in the normal development of the prostate but also in its malignant transformation. In this study, we investigated the role of suppressor of cytokine signaling 2 (SOCS2...

A regulator of G Protein signaling, RGS3, inhibits gonadotropin-releasing hormone (GnRH-stimulated luteinizing hormone (LH secretion

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Musgrove Lois C

2001-11-01

Full Text Available Abstract Background Luteinizing hormone secreted by the anterior pituitary gland regulates gonadal function. Luteinizing hormone secretion is regulated both by alterations in gonadotrope responsiveness to hypothalamic gonadotropin releasing hormone and by alterations in gonadotropin releasing hormone secretion. The mechanisms that determine gonadotrope responsiveness are unknown but may involve regulators of G protein signaling (RGSs. These proteins act by antagonizing or abbreviating interaction of Gα proteins with effectors such as phospholipase Cβ. Previously, we reported that gonadotropin releasing hormone-stimulated second messenger inositol trisphosphate production was inhibited when RGS3 and gonadotropin releasing hormone receptor cDNAs were co-transfected into the COS cell line. Here, we present evidence for RGS3 inhibition of gonadotropin releasing hormone-induced luteinizing hormone secretion from cultured rat pituitary cells. Results A truncated version of RGS3 (RGS3T = RGS3 314–519 inhibited gonadotropin releasing hormone-stimulated inositol trisphosphate production more potently than did RSG3 in gonadotropin releasing hormone receptor-bearing COS cells. An RSG3/glutathione-S-transferase fusion protein bound more 35S-Gqα than any other member of the G protein family tested. Adenoviral-mediated RGS3 gene transfer in pituitary gonadotropes inhibited gonadotropin releasing hormone-stimulated luteinizing hormone secretion in a dose-related fashion. Adeno-RGS3 also inhibited gonadotropin releasing hormone stimulated 3H-inositol phosphate accumulation, consistent with a molecular site of action at the Gqα protein. Conclusions RGS3 inhibits gonadotropin releasing hormone-stimulated second messenger production (inositol trisphosphate as well as luteinizing hormone secretion from rat pituitary gonadotropes apparently by binding and suppressing the transduction properties of Gqα protein function. A version of RGS3 that is amino

Lignans from the roots of Urtica dioica and their metabolites bind to human sex hormone binding globulin (SHBG).

Science.gov (United States)

Schöttner, M; Gansser, D; Spiteller, G

1997-12-01

Polar extracts of the stinging nettle (Urtica dioica L.) roots contain the ligans (+)-neoolivil, (-)-secoisolariciresinol, dehydrodiconiferyl alcohol, isolariciresinol, pinoresinol, and 3,4-divanillyltetrahydrofuran. These compounds were either isolated from Urtica roots, or obtained semisynthetically. Their affinity to human sex hormone binding globulin (SHBG) was tested in an in vitro assay. In addition, the main intestinal transformation products of plant lignans in humans, enterodiol and enterolactone, together with enterofuran were checked for their activity. All lignans except (-)-pinoresinol developed a binding affinity to SHBG in the in vitro assay. The affinity of (-)-3,4-divanillyltetrahydrofuran was outstandingly high. These findings are discussed with respect to potential beneficial effects of plant lignans on benign prostatic hyperplasia (BPH).

Headache And Hormones

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Shukla Rakesh

2002-01-01

Full Text Available There are many reasons to suggest a link between headache and hormones. Migraine is three times common in women as compared to men after puberty, cyclic as well as non-cyclic fluctuations in sex hormone levels during the entire reproductive life span of a women are associated with changes in frequency or severity of migraine attack, abnormalities in the hypothalamus and pineal gland have been observed in cluster headache, oestrogens are useful in the treatment of menstrual migraine and the use of melatonin has been reported in various types of primary headaches. Headache associated with various endocrinological disorders may help us in a better understanding of the nociceptive mechanisms involved in headache disorders. Prospective studies using headache diaries to record the attacks of headache and menstrual cycle have clarified some of the myths associated with menstrual migraine. Although no change in the absolute levels of sex hormones have been reported, oestrogen withdrawal is the most likely trigger of the attacks. Prostaglandins, melatonin, opioid and serotonergic mechanisms may also have a role in the pathogenesis of menstrual migraine. Guidelines have been published by the IHS recently regarding the use of oral contraceptives by women with migraine and the risk of ischaemic strokes in migraineurs on hormone replacement therapy. The present review includes menstrual migraine, pregnancy and migraine, oral contraceptives and migraine, menopause and migraine as well as the hormonal changes in chronic migraine.

In vitro assessment of thyroid hormone disrupting activities in drinking water sources along the Yangtze River

International Nuclear Information System (INIS)

Hu Xinxin; Shi Wei; Zhang Fengxian; Cao Fu; Hu Guanjiu; Hao Yingqun; Wei Si; Wang Xinru; Yu Hongxia

2013-01-01

The thyroid hormone disrupting activities of drinking water sources from the lower reaches of Yangtze River were examined using a reporter gene assay based on African green monkey kidney fibroblast (CV-1) cells. None of the eleven tested samples showed thyroid receptor (TR) agonist activity. Nine water samples exhibited TR antagonist activities with the equivalents referring to Di-n-butyl phthalate (DNBP) (TR antagonist activity equivalents, ATR-EQ 50 s) ranging from 6.92 × 10 1 to 2.85 × 10 2 μg DNBP/L. The ATR-EQ 50 s and TR antagonist equivalent ranges (ATR-EQ 30–80 ranges) for TR antagonist activities indicated that the water sample from site WX-8 posed the greatest health risks. The ATR-EQ 80 s of the water samples ranging from 1.56 × 10 3 to 6.14 × 10 3 μg DNBP/L were higher than the NOEC of DNBP. The results from instrumental analysis showed that DNBP might be responsible for the TR antagonist activities in these water samples. Water sources along Yangtze River had thyroid hormone disrupting potential. - Highlights: ► We examined thyroidal activities of drinking water sources at lower reaches of Yangtze River. ► Nine sites showed TR antagonist activities and no site exhibited TR agonist activity. ► ATR-EQ 50 s and ATR-EQ 30–80 ranges showed that the tested water samples had potential risks. ► The drinking water after water treatment processes may pose potential risks to residents. ► DBP, DEHP, NP and OP might contribute to TR antagonist activities in the aquatic environment. - Drinking water sources from the lower reaches of Yangtze River showed thyroid hormone disrupting potential in reporter gene assays.

Hormone therapy and ovarian borderline tumors

DEFF Research Database (Denmark)

Mørch, Lina Steinrud; Løkkegaard, Ellen; Andreasen, Anne Helms

2012-01-01

Little is known about the influence of postmenopausal hormone therapy on the risk of ovarian borderline tumors. We aimed at assessing the influence of different hormone therapies on this risk.......Little is known about the influence of postmenopausal hormone therapy on the risk of ovarian borderline tumors. We aimed at assessing the influence of different hormone therapies on this risk....

Association of Hormonal Contraception With Depression

DEFF Research Database (Denmark)

Skovlund, Charlotte Wessel; Mørch, Lina Steinrud; Kessing, Lars Vedel

2016-01-01

to those who never used hormonal contraception, the RR estimates for users of combined oral contraceptives increased to 1.7 (95% CI, 1.66-1.71). Conclusions and Relevance: Use of hormonal contraception, especially among adolescents, was associated with subsequent use of antidepressants and a first......Importance: Millions of women worldwide use hormonal contraception. Despite the clinical evidence of an influence of hormonal contraception on some women's mood, associations between the use of hormonal contraception and mood disturbances remain inadequately addressed. Objective: To investigate...... whether the use of hormonal contraception is positively associated with subsequent use of antidepressants and a diagnosis of depression at a psychiatric hospital. Design, Setting, and Participants: This nationwide prospective cohort study combined data from the National Prescription Register...

Effects of Growth Hormone Replacement Therapy on Bone Mineral Density in Growth Hormone Deficient Adults: A Meta-Analysis

OpenAIRE

Xue, Peng; Wang, Yan; Yang, Jie; Li, Yukun

2013-01-01

Objectives. Growth hormone deficiency patients exhibited reduced bone mineral density compared with healthy controls, but previous researches demonstrated uncertainty about the effect of growth hormone replacement therapy on bone in growth hormone deficient adults. The aim of this study was to determine whether the growth hormone replacement therapy could elevate bone mineral density in growth hormone deficient adults. Methods. In this meta-analysis, searches of Medline, Embase, and The Cochr...

Growth Hormone-Releasing Hormone in Diabetes

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Leonid Evsey Fridlyand

2016-10-01

Full Text Available Growth hormone-releasing hormone (GHRH is produced by the hypothalamus and stimulates growth hormone synthesis and release in the anterior pituitary gland. In addition GHRH is an important regulator of cellular functions in many cells and organs. Expression of GHRH G-Protein Coupled Receptor (GHRHR has been demonstrated in different peripheral tissues and cell types including pancreatic islets. Among the peripheral activities, recent studies demonstrate a novel ability of GHRH analogs to increase and preserve insulin secretion by beta-cells in isolated pancreatic islets, which makes them potentially useful for diabetes treatment. This review considers the role of GHRHR in the beta-cell and addresses the unique engineered GHRH agonists and antagonists for treatment of Type 2 diabetes mellitus. We discuss the similarity of signaling pathways activated by GHRHR in pituitary somatotrophs and in pancreatic beta-cells and possible ways as to how the GHRHR pathway can interact with glucose and other secretagogues to stimulate insulin secretion. We also consider the hypothesis that novel GHRHR agonists can improve glucose metabolism in Type 2 diabetes by preserving the function and survival of pancreatic beta-cells. Wound healing and cardioprotective action with new GHRH agonists suggesting that they may prove useful in ameliorating certain diabetic complications. These findings highlight the future potential therapeutic effectiveness of modulators of GHRHR activity for the development of new therapeutic approaches in diabetes and its complications.

Role of Anti-Müllerian Hormone in pathophysiology, diagnosis and treatment of Polycystic Ovary Syndrome: a review.

Science.gov (United States)

Dumont, Agathe; Robin, Geoffroy; Catteau-Jonard, Sophie; Dewailly, Didier

2015-12-21

Polycystic ovary syndrome (PCOS) is the most common cause of chronic anovulation and hyperandrogenism in young women. Excessive ovarian production of Anti-Müllerian Hormone, secreted by growing follicles in excess, is now considered as an important feature of PCOS. The aim of this review is first to update the current knowledge about the role of AMH in the pathophysiology of PCOS. Then, this review will discuss the improvement that serum AMH assay brings in the diagnosis of PCOS. Last, this review will explain the utility of serum AMH assay in the management of infertility in women with PCOS and its utility as a marker of treatment efficiency on PCOS symptoms. It must be emphasized however that the lack of an international standard for the serum AMH assay, mainly because of technical issues, makes it difficult to define consensual thresholds, and thus impairs the widespread use of this new ovarian marker. Hopefully, this should soon improve.

Radioimmunological determination of plasma testosterone, luteinizing hormone, folliculostimulating hormone and prolactin levels in patients with prostate cancer

International Nuclear Information System (INIS)

Milkov, V.; Maleeva, A.; Tsvetkov, M.; Visheva, N.

1986-01-01

The hormone levels were measured before and after hormonal therapy. Statistically significant changes in the levels of the hormones in this study were recognized (p<0,001) as a result of treatment with estrogen preparations. Plasma prolactin was raised before estrogen therapy (statistically significant rise, p<0,001), as compared to the levels in a control group of normal subjects. A mild tendency was observed toward its increase, depending on the duration of treatment. The results of this study show that control of the hormonal status of patients with prostate cancer may serve as reliable criterion in evaluating the effectiveness of hormonal therapy. The changes in prolactin levels are evidence of hormonal disbalance, which may be observed in these patients

Development of an assay for a biomarker of pregnancy and early fetal loss

International Nuclear Information System (INIS)

Canfield, R.E.; O'Connor, J.F.; Birken, S.; Krichevsky, A.; Wilcox, A.J.

1987-01-01

Human chorionic gonadotropin (hCG) is a glycoprotein hormone, secreted by the syncytiotrophoblast cells of the fertilized ovum, that enters the maternal circulation at the time of endometrial implantation. It is composed of two nonidentical subunits; α and β, with molecular weights of 14 kD and 23 kD, respectively. Human chorionic gonadotropin binds to the same receptor as hLH and displays the same biological response, namely, to stimulate the declining function of the corpus luteum to produce progestins and estrogen late in the menstrual cycle. The differences in the structures of hCG and hLH have been exploited to develop antibodies that can measure hCG specifically in the presence of hLH. Two-site antibody binding assays have been developed, based on a surface immunological concept of hCG epitopes, that involve four distinct regions to which antibodies against hCG can bind simultaneously. Antibody cooperative effects, in conjunction with kinetic advantages derived from the concentration factors by use of the sandwich assay technique (immunoradiometric assay, IRMA), have enabled development of extremely sensitive and specific measurement protocols for urinary hCG. The assay described herein permits the detection of pregnancy on an average 25.4 days after the first day of the preceding menses, as opposed to 29.5 days for conventional radioimmunoassay techniques. In addition, the greater sensitivity and specificity of this assay method has permitted the detection of episodes of fetal loss not detected by radioimmunoassay of urine specimens. A large scale epidemiological study is in progress using this assay technique as a way to identify pregnancies that are lost before becoming clinically apparent

Hormones and β-Agonists

NARCIS (Netherlands)

Ginkel, van L.A.; Bovee, T.F.H.; Blokland, M.H.; Sterk, S.S.; Smits, N.G.E.; Pleadin, Jelka; Vulić, Ana

2016-01-01

This chapter provides some updated information on contemporary methods for hormone and β-agonist analyses. It deals with the classical approaches for the effective detection and identification of exogenous hormones. The chapter examines specific problems related to control strategies for natural

Prognostic Value of Thyroid Hormone Levels in Patients Evaluated for Liver Transplantation

Science.gov (United States)

Van Thiel, David H.; Udani, Mahendra; Schade, Robert R.; Sanghvi, Agit; Starzl, Thomas E.

2010-01-01

The thyroid hormones T4, T3, rT3 and TSH were assayed in 134 adult patients evaluated and accepted as potential liver transplant candidates at the University of Pittsburgh from March, 1981 to December, 1983. The subsequent course of these patients was evaluated with respect to the levels of these hormones obtained at the time of acceptance for transplantation. T4 levels were increased significantly while their T3 levels were reduced (both p < 0.01) in those who survived and were discharged home as compared to either those who died waiting to be transplanted or died following the procedure. As a result, the ratio of T3/T4 was reduced markedly (p < 0.01) in those who were transplanted and survived as compared to those not transplanted or dying following transplantation. Importantly, the rT3 levels clearly separated (p < 0.01) those who would die prior to transplantation from those who would survive to be transplanted. Finally, the ratio rT3/T3 even more clearly separates those who will die prior to transplantation (p < 0.01) from the other two groups. These data suggest that thyroid hormone levels, particularly rT3 levels, might be useful in setting priorities for which patients referred for a transplantation evaluation should be accepted into the program and in determining who among accepted patients should be operated upon in preference to others also accepted and waiting to be transplanted. PMID:2993148

Some theoretical aspects of hormone receptor determination

International Nuclear Information System (INIS)

Sluiter, W.J.

1981-01-01

Suitable antisera for determination of hormone receptors are not available for the majority of hormone receptors. Therefore, the determination of hormone receptors is mostly performed in terms of binding capacity for the appropriate hormone, using radioactive hormone labels. Some theoretical aspects of such a receptor determination are discussed including the length of incubation (total or unoccupied receptor concentration), single point or multiple point (Scatchard) analysis (regarding the influence of other specific binders), the correction procedure for non-specific binding and the influence of the circulating hormone level. (Auth.)

Solid-phase peptide quantitation assay using labeled monoclonal antibody and glutaraldehyde fixation

International Nuclear Information System (INIS)

Kasprzyk, P.G.; Cuttitta, F.; Avis, I.; Nakanishi, Y.; Treston, A.; Wong, H.; Walsh, J.H.; Mulshine, J.L.

1988-01-01

A solid-phase radioimmunoassay utilizing iodinated peptide-specific monoclonal antibody as a detection system instead of labeled peptide has been developed. Regional specific monoclonal antibodies to either gastrin-releasing peptide or gastrin were used as models to validate the general application of our modified assay. Conditions for radioactive labeling of the monoclonal antibody were determined to minimize oxidant damage, which compromises the sensitivity of other reported peptide quantitation assays. Pretreatment of 96-well polyvinyl chloride test plates with a 5% glutaraldehyde solution resulted in consistent retention of sufficient target peptide on the solid-phase matrix to allow precise quantitation. This quantitative method is completed within 1 h of peptide solid phasing. Pretreatment of assay plates with glutaraldehyde increased binding of target peptide and maximized antibody binding by optimizing antigen presentation. The hypothesis that glutaraldehyde affects both peptide binding to the plate and orientation of the peptide was confirmed by analysis of several peptide analogs. These studies indicate that peptide binding was mediated through a free amino group leaving the carboxy-terminal portion of the target peptide accessible for antibody binding. It was observed that the length of the peptide also affects the amount of monoclonal antibody that will bind. Under the optimal conditions, results from quantitation of gastrin-releasing peptide in relevant samples agree well with those from previously reported techniques. Thus, we report here a modified microplate assay which may be generally applied for the rapid and sensitive quantitation of peptide hormones

Certain hormonal profiles of postpartum anestrus jersey crossbred cows treated with controlled internal drug release and ovsynch protocol

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Dayanidhi Jena

2016-10-01

Full Text Available Aim: The study was conducted to determine the serum levels of certain hormones in post-partum anestrus cows following treatment with controlled internal drug release (CIDR and Ovsynch protocol. Materials and Methods: A total of 30 postpartum anestrus cows were divided into three equal groups after thorough gynecoclinical examination. The Group 1 animals received an intravaginal progesterone device on day 0 and 2 ml of prostaglandin F2α (PGF2α on day of CIDR removal (7th day, Group 2 cows were treated with ovsynch protocol (gonadotropinreleasing hormone [GnRH]-PGF2α-GnRH on day 0, 7 and 9, respectively, and Group 3 cows were supplemented with mineral mixture and treated as control. The serum estrogen, progesterone, triiodothyronine, and thyroxine concentration were estimated using enzyme-linked immunosorbent assay kit and absorbance was read at 450 nm with Perkin Elmer Wallac 1420 Microplate Reader. Results: There was a significant increase in progesterone level in Group 1 after withdrawal of CIDR as compared to other two groups. However, the estrogen assay revealed a greater concentration in Group 2 against Group 1 on day 7 of sampling. However, there was no significant difference for serum triiodothyronine (T3 and thyroxine (T4 irrespective of treatment protocols and days of sampling. Conclusion: Treatment with CIDR based progesterone therapy and drug combinations may affect the reproductive hormonal balance like estrogen and progesterone, which is inevitable for successful return to cyclicity and subsequent fertilization and conception. However, as far as serum T3 and T4 concentration concerned it may not give an astounding result.

Prolonged inhibition of luteinizing hormone and testosterone levels in male rats with the luteinizing hormone-releasing hormone antagonist SB-75.

Science.gov (United States)

Bokser, L; Bajusz, S; Groot, K; Schally, A V

1990-09-01

Inhibitory effects of the potent antagonist of luteinizing hormone-releasing hormone N-Ac-[3-(2-naphthyl)-D-alanine1,4-chloro-D-phenylalanine2,3- (3-pyridyl)-D- alanine3,D-citrulline6,D-alanine10]luteinizing hormone-releasing hormone (SB-75) free of edematogenic effects were investigated in male rats. In a study to determine the effect on luteinizing hormone levels in castrated male rats, SB-75 was injected s.c. in doses of 0.625, 1.25, 2.5, 5.0, and 10 micrograms. Blood samples were taken at different intervals for 48 hr. All doses of SB-75 significantly decreased luteinizing hormone levels for greater than 6 hr (P less than 0.01); this inhibition lasted for greater than 24 hr (P less than 0.01) with a dose of 5.0 micrograms and greater than 48 hr with 10 micrograms (P less than 0.05). Serum testosterone levels were also measured in intact male rats injected with SB-75 in doses of 25, 50, and 100 micrograms. All doses produced a dramatic fall in testosterone to castration levels 6 hr after injection (P less than 0.01); this inhibition of serum testosterone was maintained for greater than 72 hr, but only the 100-micrograms dose could keep testosterone in the castration range for greater than 24 hr (P less than 0.01). In another study using a specific RIA, we obtained the pharmacokinetic release pattern of SB-75 from two sustained delivery formulations of SB-75 pamoate microgranules and examined their effect on serum testosterone. After a single i.m. injection of 20 mg of one batch of microgranules, a large peak corresponding to SB-75 at 45.8 ng/ml was observed, corresponding to the "burst" effect. Levels of the analog decreased to 19.6 ng/ml on day 2, gradually reached a concentration of 4.7 ng/ml on day 7, and kept declining thereafter. Testosterone levels were reduced on day 1 (P less than 0.01) and were maintained at low values for greater than 7 days (P less than 0.05). In rats injected with 10 mg of SB-75 pamoate microgranules of the second batch, SB-75 serum

Masturbation frequency and sexual function domains are associated with serum reproductive hormone levels across the menopausal transition.

Science.gov (United States)

Randolph, John F; Zheng, Huiyong; Avis, Nancy E; Greendale, Gail A; Harlow, Siobán D

2015-01-01

To determine whether reproductive hormones are related to sexual function during the menopausal transition. The Study of Women's Health Across the Nation (SWAN) is a multiethnic cohort study of the menopausal transition located at seven US sites. At baseline, the 3302 community-based participants, aged 42-52, had an intact uterus and at least one ovary and were not using exogenous hormones. Participants self-identified as White, Black, Hispanic, Chinese, or Japanese. At baseline and at each of the 10 follow-up visits, sexual function was assessed by self-administered questionnaires, and blood was drawn to assay serum levels of T, estradiol, FSH, SHBG, and dehydroepiandrosterone sulfate. Self-reported frequency of masturbation, sexual desire, sexual arousal, orgasm, and pain during intercourse. Masturbation, sexual desire, and arousal were positively associated with T. Masturbation, arousal, and orgasm were negatively associated with FSH. Associations were modest. Estradiol was not related to any measured sexual function domain. Pain with intercourse was not associated with any hormone. Reproductive hormones were associated with sexual function in midlife women. T was positively associated, supporting the role of androgens in female sexual function. FSH was negatively associated, supporting the role of menopausal status in female sexual function. The modest associations in this large study suggest that the relationships are subtle and may be of limited clinical significance.

Sex, hormones and neurogenesis in the hippocampus: hormonal modulation of neurogenesis and potential functional implications.

Science.gov (United States)

Galea, L A M; Wainwright, S R; Roes, M M; Duarte-Guterman, P; Chow, C; Hamson, D K

2013-11-01

The hippocampus is an area of the brain that undergoes dramatic plasticity in response to experience and hormone exposure. The hippocampus retains the ability to produce new neurones in most mammalian species and is a structure that is targeted in a number of neurodegenerative and neuropsychiatric diseases, many of which are influenced by both sex and sex hormone exposure. Intriguingly, gonadal and adrenal hormones affect the structure and function of the hippocampus differently in males and females. Adult neurogenesis in the hippocampus is regulated by both gonadal and adrenal hormones in a sex- and experience-dependent way. Sex differences in the effects of steroid hormones to modulate hippocampal plasticity should not be completely unexpected because the physiology of males and females is different, with the most notable difference being that females gestate and nurse the offspring. Furthermore, reproductive experience (i.e. pregnancy and mothering) results in permanent changes to the maternal brain, including the hippocampus. This review outlines the ability of gonadal and stress hormones to modulate multiple aspects of neurogenesis (cell proliferation and cell survival) in both male and female rodents. The function of adult neurogenesis in the hippocampus is linked to spatial memory and depression, and the present review provides early evidence of the functional links between the hormonal modulation of neurogenesis that may contribute to the regulation of cognition and stress. © 2013 British Society for Neuroendocrinology.

Assay of free thyroxine and free triiodothyronine in fine-needle aspiration of thyroid nodules: a useful and low-cost assessment.

Science.gov (United States)

Barbaro, Daniele; Macchia, Enrico; Orsini, Paola; Piazza, Francesca; Lapi, Paola; Pasquini, Cristina

2004-01-01

To evaluate whether analysis of thyroid hormones in fine-needle aspiration (FNA) of thyroid nodules can provide information about the functional status and the nature of the nodules. We studied 4 groups of patients: group 1, 17 patients with autonomous hyperfunctioning thyroid nodules; group 2, 52 patients with cold nonfunctioning thyroid nodules; group 3, 12 patients with malignant thyroid nodules; and group 4 (control group), 10 patients with nonthyroid nodular lesions (enlarged parathyroid glands or lymph nodes). The assay of thyroid hormones was performed in FNA after the washing of needles and, with patient consent, also in normal thyroid parenchyma. The free thyroxine (FT(4)) and free triiodothyronine (FT(3)) values were remarkably high in group 1 (mean, 5.5 +/- 0.53 ng/dL and 27.6 +/- 3.1 pg/mL, respectively; Pnodules. These results show that assay of FT(4) and FT(3) in FNA can yield information about the functional status of thyroid nodules and, indirectly, about the nature of nodules. In this era of sophisticated new molecular markers in FNA cytology, this low-cost diagnostic method can be readily performed in every laboratory.

Would male hormonal contraceptives affect cardiovascular risk?

Directory of Open Access Journals (Sweden)

Michael Zitzmann

2018-01-01

Full Text Available The aim of hormonal male contraception is to prevent unintended pregnancies by suppressing spermatogenesis. Hormonal male contraception is based on the principle that exogenous administration of androgens and other hormones such as progestins suppress circulating gonadotropin concentrations, decreasing testicular Leydig cell and Sertoli cell activity and spermatogenesis. In order to achieve more complete suppression of circulating gonadotropins and spermatogenesis, a progestin has been added testosterone to the most recent efficacy trials of hormonal male contraceptives. This review focusses on the potential effects of male hormonal contraceptives on cardiovascular risk factors, lipids and body composition, mainly in the target group of younger to middle-aged men. Present data suggest that hormonal male contraception can be reasonably regarded as safe in terms of cardiovascular risk. However, as all trials have been relatively short (< 3 years, a final statement regarding the cardiovascular safety of hormonal male contraception, especially in long-term use, cannot be made. Older men with at high risk of cardiovascular event might not be good candidates for hormonal male contraception. The potential adverse effects of hormonal contraceptives on cardiovascular risk appear to depend greatly on the choice of the progestin in regimens for hormonal male contraceptives. In the development of prospective hormonal male contraception, data on longer-term cardiovascular safety will be essential.

Development of radiolabeling method for natural juvenile hormones

International Nuclear Information System (INIS)

Okuda, Takashi; Shiotsuki, Takahiro; Kotaki, Toyomi

2000-01-01

This study aimed to develop a new assay method for accurate determination of juvenile hormone (JH) using radioisotope. A new measuring method for JH was designed based on the principle of molecular competition. Namely, JH-binding protein in the insect was used to form a selective binding to JH. At first, corpus allatum was cultured in a medium containing 3 H or 14 C epoxyfarnesyldiazoacetate (EFDA), which is a photoaffinity labeling reagent and JH binding protein (JHBP) was purified using 3 H or 14 C labeled EFDA. Since several kinds of JH homologues different in the molecular structure have been known, it was needed to establish each labeling method appropriate to those homologues. Then, an assay method for micro-quantitative measurement of JH was established utilizing the competition between labeled natural JH and JHBP. Thus, the authors succeeded in the overexpression of the blood JHBA of kind of tabaco moth, H.virescens and also in cloning and overexpression of JHBP in the silk worm. It was confirmed that these JHBPs specifically bind to 3 H labeled JH3, leading to stable supply of blood JHBP. Thus, accurate assay for JH concentration became possible by the use of the labeled JH with natural configuration and the blood JHBP. In the course of this study, several findings were obtained as follows: The JHBP of a sting bug was different from the previously reported ones. The regulation of JH synthesis in the corpus allatum was closely related to the control of diapause in several insects. The JHBP isolated from the cytosol of silk gland was a new protein in respect of amino acid sequence. (M.N.)

Development of radiolabeling method for natural juvenile hormones

Energy Technology Data Exchange (ETDEWEB)

Okuda, Takashi; Shiotsuki, Takahiro; Kotaki, Toyomi [National Inst. of Sericultural and Entomological Science, Tsukuba, Ibaraki (Japan)

2000-02-01

This study aimed to develop a new assay method for accurate determination of juvenile hormone (JH) using radioisotope. A new measuring method for JH was designed based on the principle of molecular competition. Namely, JH-binding protein in the insect was used to form a selective binding to JH. At first, corpus allatum was cultured in a medium containing {sup 3}H or {sup 14}C epoxyfarnesyldiazoacetate (EFDA), which is a photoaffinity labeling reagent and JH binding protein (JHBP) was purified using {sup 3}H or {sup 14}C labeled EFDA. Since several kinds of JH homologues different in the molecular structure have been known, it was needed to establish each labeling method appropriate to those homologues. Then, an assay method for micro-quantitative measurement of JH was established utilizing the competition between labeled natural JH and JHBP. Thus, the authors succeeded in the overexpression of the blood JHBA of kind of tabaco moth, H.virescens and also in cloning and overexpression of JHBP in the silk worm. It was confirmed that these JHBPs specifically bind to {sup 3}H labeled JH3, leading to stable supply of blood JHBP. Thus, accurate assay for JH concentration became possible by the use of the labeled JH with natural configuration and the blood JHBP. In the course of this study, several findings were obtained as follows: The JHBP of a sting bug was different from the previously reported ones. The regulation of JH synthesis in the corpus allatum was closely related to the control of diapause in several insects. The JHBP isolated from the cytosol of silk gland was a new protein in respect of amino acid sequence. (M.N.)

Hormone Replacement Therapy and Your Heart

Science.gov (United States)

Hormone replacement therapy and your heart Are you taking — or considering — hormone therapy to treat bothersome menopausal symptoms? Understand ... you. By Mayo Clinic Staff Long-term hormone replacement therapy used to be routinely prescribed for postmenopausal ...

Childhood lead toxicity and impaired release of thyrotropin-stimulating hormone

International Nuclear Information System (INIS)

Huseman, C.A.; Moriarty, C.M.; Angle, C.R.

1987-01-01

Decreased stature of children is epidemiologically associated with increased blood lead independent of multiple socioeconomic and nutritional variables. Since endocrine dysfunction occurs in adult lead workers, they studied two girls, 2 years of age, before and after calcium disodium edetate chelation for blood leads (PbB) of 19-72 μg/dl. The height of both children had crossed from the 50th to below the 10th percentile during the course of chronic lead toxicity. Basal free T 4 , T 4 , T 3 , cortisol, somatomedin C, and sex steroids were normal. A decrease in the growth hormone response and elevation of basal prolcatin and gonadotropins were noted in one. Both children demonstrated blunted thyrotropin-stimulating hormone (TSH) responses to thyrotropin-releasing hormone (TRH) in six of seven challenges. This prompted in vitro studies of cultured cells from rat pituitarities. After incubation of pituitary cells with 0.1-10 μM Pb 2+ for 2 hr, followed by the addition of TRH, there was a dose-dependent inhibition of TSH release Lead did not interfere with the assay of TSH. To investigate the interaction of lead and calcium, 45 Ca 2+ kinetic analyses were done on rat pituitary slices after 1 hr incubation with 1.0 μM lead. The impaired late efflux was consistent with a decrease in the size and exchangeability of the tightly bound pool of intracellular microsomal or mitochondrial calcium. The rat pituitary cell model provides a model for the decreased TSH release of lead poisoning, supports the biological plausibility of a neuroendocrine effect on growth, and suggests that interference with calcium-mediated intracellular responses is a basic mechanism of lead toxicity

Gastrointestinal Hormones Induced the Birth of Endocrinology.

Science.gov (United States)

Wabitsch, Martin

2017-01-01

The physiological studies by British physiologists William Maddock Bayliss and Ernest Henry Starling, at the beginning of the last century, demonstrated the existence of specific messenger molecules (hormones) circulating in the blood that regulate the organ function and physiological mechanisms. These findings led to the concept of endocrinology. The first 2 hormones were secretin, discovered in 1902, and gastrin, discovered in 1905. Both hormones that have been described are produced in the gut. This chapter summarizes the history around the discovery of these 2 hormones, which is perceived as the birth of endocrinology. It is noteworthy that after the discovery of these 2 gastrointestinal hormones, many other hormones were detected outside the gut, and thereafter gut hormones faded from both the clinical and scientific spotlight. Only recently, the clinical importance of the gut as the body's largest endocrine organ producing a large variety of hormones has been realized. Gastrointestinal hormones are essential regulators of metabolism, growth, development and behavior and are therefore the focus of a modern pediatric endocrinologist. © 2017 S. Karger AG, Basel.

Ghrelin: much more than a hunger hormone

Science.gov (United States)

Ghrelin is a multifaceted gut hormone that activates its receptor, growth hormone secretagogue receptor (GHS-R). Ghrelin's hallmark functions are its stimulatory effects on growth hormone release, food intake and fat deposition. Ghrelin is famously known as the 'hunger hormone'. However, ample recen...

Pituitary-hormone secretion by thyrotropinomas

OpenAIRE

Roelfsema, Ferdinand; Kok, Simon; Kok, Petra; Pereira, Alberto M.; Biermasz, Nienke R.; Smit, Jan W.; Frolich, Marijke; Keenan, Daniel M.; Veldhuis, Johannes D.; Romijn, Johannes A.

2008-01-01

Hormone secretion by somatotropinomas, corticotropinomas and prolactinomas exhibits increased pulse frequency, basal and pulsatile secretion, accompanied by greater disorderliness. Increased concentrations of growth hormone (GH) or prolactin (PRL) are observed in about 30% of thyrotropinomas leading to acromegaly or disturbed sexual functions beyond thyrotropin (TSH)-induced hyperthyroidism. Regulation of non-TSH pituitary hormones in this context is not well understood. We there therefore ev...

Headaches and Hormones: What's the Connection?

Science.gov (United States)

Headaches and hormones: What's the connection? Being female has some real health advantages, but not when it comes to headaches — particularly ... a relationship between headaches and hormonal changes. The hormones estrogen (ES-truh-jen) and progesterone (pro-JES- ...

Trimester- and Assay-Specific Thyroid Reference Intervals for Pregnant Women in China

Directory of Open Access Journals (Sweden)

Jinfang Xing

2016-01-01

Full Text Available Objective. The guidelines of the American Thyroid Association (ATA recommend an upper limit reference interval (RI of thyroid stimulating hormone (TSH of 2.5 mIU/L in the first trimester of pregnancy and 3.0 mIU/L in subsequent trimesters, but some reported ranges in China are significantly higher. Our study aimed to establish trimester- and assay-specific RIs for thyroid hormones in normal pregnant Chinese women. Methods. In this cross-sectional study, 2540 women with normal pregnancies (first trimester, n=398; second trimester, n=797; third trimester, n=1345 and 237 healthy nonpregnant control subjects were recruited. Serum TSH, free thyroxin (FT4, thyroid peroxidase antibody (TPOAb, and thyroglobulin antibody (TgAb levels were determined by automated chemiluminescence with an Immulite 2000 system (Siemens, Erlangen, Germany. After outliers were excluded, the 2.5–97.5th percentiles were used to define the RIs. Results. The RIs of thyroid function in the first, second, and third trimesters of pregnancy and in nonpregnant controls were 0.07–3.96, 0.27–4.53, 0.48–5.40, and 0.69–5.78 mIU/L for TSH and 9.16–18.12, 8.67–16.21, 7.80–13.90, and 8.24–16.61 pmol/L for FT4, respectively. Conclusion. The trimester- and assay-specific RIs of thyroid function during pregnancy differed between trimesters, which suggests that it is advisable to detect and avoid misclassification of thyroid dysfunction during pregnancy for women in Henan, China.

Interactions between hormones and epilepsy.

Science.gov (United States)

Taubøll, Erik; Sveberg, Line; Svalheim, Sigrid

2015-05-01

There is a complex, bidirectional interdependence between sex steroid hormones and epilepsy; hormones affect seizures, while seizures affect hormones thereby disturbing reproductive endocrine function. Both female and male sex steroid hormones influence brain excitability. For the female sex steroid hormones, progesterone and its metabolites are anticonvulsant, while estrogens are mainly proconvulsant. The monthly fluctuations in hormone levels of estrogen and progesterone are the basis for catamenial epilepsy described elsewhere in this issue. Androgens are mainly anticonvulsant, but the effects are more varied, probably because of its metabolism to, among others, estradiol. The mechanisms for the effects of sex steroid hormones on brain excitability are related to both classical, intracellularly mediated effects, and non-classical membrane effects due to binding to membrane receptors. The latter are considered the most important in relation to epilepsy. The different sex steroids can also be further metabolized within the brain to different neurosteroids, which are even more potent with regard to their effect on excitability. Estrogens potentiate glutamate responses, primarily by potentiating NMDA receptor activity, but also by affecting GABA-ergic mechanisms and altering brain morphology by increasing dendritic spine density. Progesterone and its main metabolite 5α-pregnan-3α-ol-20-one (3α-5α-THP) act mainly to enhance postsynaptic GABA-ergic activity, while androgens enhance GABA-activated currents. Seizures and epileptic discharges also affect sex steroid hormones. There are close anatomical connections between the temporolimbic system and the hypothalamus controlling the endocrine system. Several studies have shown that epileptic activity, especially mediated through the amygdala, alters reproductive function, including reduced ovarian cyclicity in females and altered sex steroid hormone levels in both genders. Furthermore, there is an asymmetric

Toxic effects of arsenic on semen and hormonal profile and their amelioration with vitamin E in Teddy goat bucks.

Science.gov (United States)

Zubair, M; Ahmad, M; Jamil, H; Deeba, F

2016-12-01

The present environmental study has been planned to investigate the toxic effects of arsenic on reproductive functions of Teddy bucks as well as to examine whether these toxic effects are ameliorated by vitamin E. Sixteen adult Teddy bucks were divided randomly into four equal groups A, B, C and D with following treatment: A (control), B (sodium arsenite 5 mg kg -1 BW day -1 ), C (vit E 200 mg kg -1 BW day -1  + Arsenic 5 mg kg -1 BW day -1 ) and D (vit E 200 mg kg -1 BW day -1 ). This treatment was continued for 84 days. Semen quality parameters were evaluated weekly. Male testosterone, luteinising hormone (LH), follicle-stimulating hormone (FSH) and cortisol levels were measured through enzyme-linked immunosorbent assay (ELISA) after every 2 weeks. The data were subjected to two-way analysis of variance followed by Duncan test for multiple comparisons. Semen evaluation parameters were reduced significantly (P semen and hormonal parameters. It may be concluded from this study that sodium arsenite causes major toxicity changes in semen and hormonal profile in Teddy goat bucks and vitamin E has ameliorative effects on these toxic changes. © 2016 Blackwell Verlag GmbH.

Exposure to organophosphate pesticides and male hormone profile in floriculturist of the state of Morelos, Mexico.

Science.gov (United States)

Blanco-Muñoz, Julia; Morales, Magally Mayanin; Lacasaña, Marina; Aguilar-Garduño, Clemente; Bassol, Susana; Cebrián, Mariano E

2010-07-01

Studies on experimental animals have found that organophosphate (OP) pesticides may act as endocrine disruptors; however, their effects on the human hormonal profile have not yet been adequately characterized. We evaluate the association between exposure to OP pesticides, measured through dialkyl phosphate (DAP) metabolites urinary levels, and the male hormone profile. A cross-sectional study was performed in 104 floriculturists of Morelos, Mexico. A structured questionnaire was applied to get information on sociodemographic characteristics, anthropometry, clinical history, alcohol and tobacco consumption, and work history. DAP metabolites [dimethylphosphate (DMP), dimethylthiophosphate, dimethyldithiophosphate, diethylphosphate (DEP), diethylthiophosphate (DETP) and diethyldithiophosphate] were determined using gas-liquid chromatography. Serum levels of FSH, LH, prolactin, testosterone, inhibin B and estradiol were determined using enzyme-linked immunosorbent assay. Multiple linear regression was used to study the association between DAP metabolite levels and male hormonal profile. Data were adjusted by p,p'-dichlorodiphenyldichloroethene serum levels and other potential confounders. There was a negative association between inhibin B and urinary levels of DMP, DEP, DETP and total DAP metabolites. DEP levels were negatively associated with serum FSH concentrations, but marginally and positively associated with those of testosterone. DETP was marginally associated with lower LH serum levels. There were no other significant associations among OP metabolites and serum hormone levels. Inhibin B and FSH vary according to levels of DAP metabolites in men occupationally exposed to OP pesticides. These results suggest that OP pesticides could act as endocrine disruptors in humans; however, most hormonal values fell within the wide normal range and associations were small. There is, therefore, a need for further investigation to elucidate their biological and clinical

Parathyroid hormone-related protein blood test

Science.gov (United States)

... ency/article/003691.htm Parathyroid hormone-related protein blood test To use the sharing features on this page, ... measures the level of a hormone in the blood, called parathyroid hormone-related protein. How the Test is Performed A blood sample is needed . How ...

Thyroid hormone signaling in the hypothalamus

NARCIS (Netherlands)

Alkemade, Anneke; Visser, Theo J.; Fliers, Eric

2008-01-01

PURPOSE OF REVIEW: Proper thyroid hormone signaling is essential for brain development and adult brain function. Signaling can be disrupted at many levels due to altered thyroid hormone secretion, conversion or thyroid hormone receptor binding. RECENT FINDINGS: Mutated genes involved in thyroid

Obesity, growth hormone and weight loss

DEFF Research Database (Denmark)

Rasmussen, Michael Højby

2009-01-01

Growth hormone (GH) is the most important hormonal regulator of postnatal longitudinal growth in man. In adults GH is no longer needed for longitudinal growth. Adults with growth hormone deficiency (GHD) are characterised by perturbations in body composition, lipid metabolism, cardiovascular risk...

Human adrenocarcinoma (H295R) cells for rapid in vitro determination of effects on steroidogenesis: Hormone production

International Nuclear Information System (INIS)

Hecker, Markus; Newsted, John L.; Murphy, Margaret B.; Higley, Eric B.; Jones, Paul D.; Wu, Rudolf; Giesy, John P.

2006-01-01

To identify and prioritize chemicals that may alter steroidogenesis, an in vitro screening assay based on measuring alterations in hormone production was developed using the H295R human adrenocortical carcinoma cell line. Previous studies indicated that this cell line was useful to screen for effects on gene expression of steroidogenic enzymes. This study extended that work to measure the integrated response on production of testosterone (T), estradiol (E2), and progesterone/pregnenolone (P) using an ELISA. Under optimized culture and experimental conditions, the basal release of P, T and E2 into the medium was 7.0 ± 1.2 ng/ml, 1.6 ± 0.4 ng/ml, and 0.51 ± 0.13 ng/ml, respectively. Model chemicals with different modes of action on steroidogenic systems were tested. Exposure to forskolin resulted in dose-dependent increases in all three hormones with the greatest relative increase being observed for E2. This differed from cells exposed to prochloraz or ketoconazole where P concentrations increased while T and E2 concentrations decreased in a dose-dependent manner. In cells exposed to fadrozole, E2 decreased in a dose-dependent manner while T and P only decreased at the greatest dose tested. Aminoglutethimide decreased P and E2 concentrations but increased T concentrations. Vinclozolin reduced both P and T but resulted in a slight increase in E2. The alteration in the patterns of hormone production in the H295R assay was consistent with the modes of action of the chemicals and was also consistent with observed effects of these chemicals in animal models. Based on these results, the H295R in vitro system has potential for high throughput screening to not only characterize the effects of chemicals on endocrine systems but also to prioritize chemicals for additional testing

Hormone therapy and ovarian cancer

DEFF Research Database (Denmark)

Mørch, Lina Steinrud; Løkkegaard, Ellen; Andreasen, Anne Helms

2009-01-01

CONTEXT: Studies have suggested an increased risk of ovarian cancer among women taking postmenopausal hormone therapy. Data are sparse on the differential effects of formulations, regimens, and routes of administration. OBJECTIVE: To assess risk of ovarian cancer in perimenopausal and postmenopau......CONTEXT: Studies have suggested an increased risk of ovarian cancer among women taking postmenopausal hormone therapy. Data are sparse on the differential effects of formulations, regimens, and routes of administration. OBJECTIVE: To assess risk of ovarian cancer in perimenopausal...... and postmenopausal women receiving different hormone therapies. DESIGN AND SETTING: Nationwide prospective cohort study including all Danish women aged 50 through 79 years from 1995 through 2005 through individual linkage to Danish national registers. Redeemed prescription data from the National Register...... bands included hormone exposures as time-dependent covariates. PARTICIPANTS: A total of 909,946 women without hormone-sensitive cancer or bilateral oophorectomy. MAIN OUTCOME MEASURE: Ovarian cancer. RESULTS: In an average of 8.0 years of follow-up (7.3 million women-years), 3068 incident ovarian...

Assay for plasma somatomedin: (/sup 3/H)thymidine incorporation by isolated rabbit chondrocytes

Energy Technology Data Exchange (ETDEWEB)

Ashton, I K; Francis, M J.O. [Nuffield Orthopaedic Centre, Oxford (UK)

1977-01-01

The incorporation of (/sup 3/H)thymidine by rabbit chondrocytes in vitro has been developed as a sensitive assay for plasma somatomedin. A concentration of normal plasma of 2.5% enhanced (/sup 3/H)thymidine incorporation by 5- to 20-fold compared with basal levels in the absence of plasma. The mean potency of plasma from normal adult men was 0.96 +-0.1 u./ml (mean +- S.D.) and from acromegalic patients 1.9 +- 0.4 u./ml. The apparent potency of hypopituitary plasma alone increased on heating which suggested the presence of heat-labile inhibitors of somatomedin activity. The potency of heated hypopituitary plasma (0.6 +- 0.09 u./ml) remained significantly lower (P < 0.01) than normal plasma. Human growth hormone (0.1 to 20 ..mu..u/ml), bovine growth hormone (0.5 to 20 ..mu..u/ml), insulin (0.5 to 5 ..mu..u/ml) and glucose (0.3 to 2 mmol/l) had no direct effect on the incorporation of (/sup 3/H)thymidine. Chondrocytes which had been previously stored frozen also showed a response to plasma somatomedin.

Production and purification of polyclonal antibody against melatonin hormone

Directory of Open Access Journals (Sweden)

Fooladsaz K

1999-09-01

Full Text Available Nowadays immunochemical techniques have played a very important and valuable role in quantitative and qualitative assays of liquid compounds of the body. Producing antibody against immunogenes is the first step to make immunochemical kits. In this study production and purification of polyclonal antibody against melatonin has been considered. This hormone which has several important functions in physiological conditions such as migraine, cirrhosis, mammary gland cancer and other diseases, is the most important pineal gland secretion. This gland is a circumventricular organ of brain and according to histological and anatomical studies, it is a high secretory organ, that secretes active biological substances like melatonin, oxytocin, serotonin and ect. In this study, melatonin has been considered as hapten and has become an immunogen by being linked to the bovine serum Albumin. Then, by the immunization of three white New Zeland rabbits that had the booster injections in regular intervals, the antibody titer was detected to be 1/2000, by using checkboard curves, and with the use of melatonin linked to penicillinase as a labeled antigen, the titer was detected 1/200. Finally an antibody with high purification rate has been obtained, which can be used in immunochemical assays like RIA, ELISA, and EIA.

Bioanalytical and instrumental analysis of thyroid hormone disrupting compounds in water sources along the Yangtze River

International Nuclear Information System (INIS)

Shi Wei; Wang Xiaoyi; Hu Guanjiu; Hao Yingqun; Zhang Xiaowei; Liu Hongling; Wei Si; Wang Xinru; Yu Hongxia

2011-01-01

Thyroid hormone (TH) agonist and antagonist activities of water sources along the Yangtze River in China were surveyed by a green monkey kidney fibroblast (CV-1) cell-based TH reporter gene assay. Instrumental analysis was conducted to identify the responsible thyroid-active compounds. Instrumentally derived L-3,5,3'-triiodothyronine (T 3 ) equivalents (T 3 -EQs) and thyroid receptor (TR) antagonist activity equivalents referring to dibutyl phthalate (DBP-EQs) were calculated from the concentrations of individual congeners. The reporter gene assay demonstrated that three out of eleven water sources contained TR agonist activity equivalents (TR-EQs), ranging from 286 to 293 ng T 3 /L. Anti-thyroid hormone activities were found in all water sources with the TR antagonist activity equivalents referring to DBP (Ant-TR-EQs), ranging from 51.5 to 555.3 μg/L. Comparisons of the equivalents from instrumental and biological assays suggested that high concentrations of DBP and di-2-ethylhexyl phthalate (DEHP) were responsible for the observed TR antagonist activities at some locations along the Yangtze River. - Research highlights: → First of all, we indicated the instrumentally derived L-3,5,3'-triiodothyronine (T 3 ) equivalents (T 3 -EQs) and thyroid receptor (TR) antagonist activity equivalents referring to DBP (DBP-EQs) for the very first time. → Secondly, high concentrations of DBP and DEHP might be responsible for the observed TR antagonist activities at some locations. → Finally, we found that thyroid receptor (TR) antagonist activities were very common in Yangtze River. More attentions should be paid to the TR antagonist activities and the responsible compounds. - In vitro bioassay responses observed in Yangtze River source water extracts showed great TR antagonist activities, and DBP and DEHP were responsible.

Bioanalytical and instrumental analysis of thyroid hormone disrupting compounds in water sources along the Yangtze River

Energy Technology Data Exchange (ETDEWEB)

Shi Wei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wang Xiaoyi [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Jiangsu Academy of Environmental Science, Nanjing 210036 (China); Hu Guanjiu; Hao Yingqun [State Environmental Protection Key Laboratory of Monitoring and Analysis for Organic Pollutants in Surface Water, Jiangsu Provincial Environmental Monitoring Center, Nanjing 210036 (China); Zhang Xiaowei [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Liu Hongling, E-mail: hlliu@nju.edu.c [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wei Si [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China); Wang Xinru [Key Laboratory of Reproductive Medicine and Institute of Toxicology, Nanjing Medical University, Nanjing 210029 (China); Yu Hongxia, E-mail: hongxiayu@nju.edu.c [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093 (China)

2011-02-15

Thyroid hormone (TH) agonist and antagonist activities of water sources along the Yangtze River in China were surveyed by a green monkey kidney fibroblast (CV-1) cell-based TH reporter gene assay. Instrumental analysis was conducted to identify the responsible thyroid-active compounds. Instrumentally derived L-3,5,3'-triiodothyronine (T{sub 3}) equivalents (T{sub 3}-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to dibutyl phthalate (DBP-EQs) were calculated from the concentrations of individual congeners. The reporter gene assay demonstrated that three out of eleven water sources contained TR agonist activity equivalents (TR-EQs), ranging from 286 to 293 ng T{sub 3}/L. Anti-thyroid hormone activities were found in all water sources with the TR antagonist activity equivalents referring to DBP (Ant-TR-EQs), ranging from 51.5 to 555.3 {mu}g/L. Comparisons of the equivalents from instrumental and biological assays suggested that high concentrations of DBP and di-2-ethylhexyl phthalate (DEHP) were responsible for the observed TR antagonist activities at some locations along the Yangtze River. - Research highlights: First of all, we indicated the instrumentally derived L-3,5,3'-triiodothyronine (T{sub 3}) equivalents (T{sub 3}-EQs) and thyroid receptor (TR) antagonist activity equivalents referring to DBP (DBP-EQs) for the very first time. Secondly, high concentrations of DBP and DEHP might be responsible for the observed TR antagonist activities at some locations. Finally, we found that thyroid receptor (TR) antagonist activities were very common in Yangtze River. More attentions should be paid to the TR antagonist activities and the responsible compounds. - In vitro bioassay responses observed in Yangtze River source water extracts showed great TR antagonist activities, and DBP and DEHP were responsible.

Peptide Hormones in the Gastrointestinal Tract

DEFF Research Database (Denmark)

Rehfeld, Jens F.

2015-01-01

Gastrointestinal hormones are peptides released from endocrine cells and neurons in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gastrointestinal tract, which makes the gut the largest hormone-producing organ in the body. Modern biology makes it feasi...

Growth hormone-mediated breakdown of body fat

DEFF Research Database (Denmark)

Johansen, T.; Malmlöf, K.; Richelsen, Bjørn

2003-01-01

regimen. Twelve-month-old rats fed first a high-fat diet or a low-fat diet for 14 weeks were injected with saline or growth hormone (4 mg/kg/d) for four days or three weeks in different combinations with either high- or low-fat diets. In adipose tissue, growth hormone generally inhibited lipoprotein...... lipase and also attenuated the inhibiting effect of insulin on hormone-sensitive lipase activity. Growth hormone treatment combined with restricted high-fat feeding reduced the activity of both lipases in adipose tissue and stimulated hormone-sensitive lipase in muscle. Generally, plasma levels of free...... fatty acids, glycerol and cholesterol were reduced by growth hormone, and in combination with restricted high-fat feeding, triglyceride levels improved too. We conclude that growth hormone inhibits lipid storage in adipose tissue by reducing both lipoprotein lipase activity and insulin's inhibitory...

Ovarian hormones and obesity.

Science.gov (United States)

Leeners, Brigitte; Geary, Nori; Tobler, Philippe N; Asarian, Lori

2017-05-01

Obesity is caused by an imbalance between energy intake, i.e. eating and energy expenditure (EE). Severe obesity is more prevalent in women than men worldwide, and obesity pathophysiology and the resultant obesity-related disease risks differ in women and men. The underlying mechanisms are largely unknown. Pre-clinical and clinical research indicate that ovarian hormones may play a major role. We systematically reviewed the clinical and pre-clinical literature on the effects of ovarian hormones on the physiology of adipose tissue (AT) and the regulation of AT mass by energy intake and EE. Articles in English indexed in PubMed through January 2016 were searched using keywords related to: (i) reproductive hormones, (ii) weight regulation and (iii) central nervous system. We sought to identify emerging research foci with clinical translational potential rather than to provide a comprehensive review. We find that estrogens play a leading role in the causes and consequences of female obesity. With respect to adiposity, estrogens synergize with AT genes to increase gluteofemoral subcutaneous AT mass and decrease central AT mass in reproductive-age women, which leads to protective cardiometabolic effects. Loss of estrogens after menopause, independent of aging, increases total AT mass and decreases lean body mass, so that there is little net effect on body weight. Menopause also partially reverses women's protective AT distribution. These effects can be counteracted by estrogen treatment. With respect to eating, increasing estrogen levels progressively decrease eating during the follicular and peri-ovulatory phases of the menstrual cycle. Progestin levels are associated with eating during the luteal phase, but there does not appear to be a causal relationship. Progestins may increase binge eating and eating stimulated by negative emotional states during the luteal phase. Pre-clinical research indicates that one mechanism for the pre-ovulatory decrease in eating is a

Generalized resistance to thyroid hormone associated with a mutation in the ligand-binding domain of the human thyroid hormone receptor β

International Nuclear Information System (INIS)

Sakurai, A.; Takeda, K.; Ain, K.; Ceccarelli, P.; Nakai, A.; Seino, S.; Bell, G.I.; Refetoff, S.; DeGroot, L.J.

1989-01-01

The syndrome of generalized resistance to thyroid hormone is characterized by elevated circulating levels of thyroid hormone in the presence of an overall eumetabolic state and failure to respond normally to triiodothyronine. The authors have evaluated a family with inherited generalized resistance to thyroid hormone for abnormalities in the thyroid hormone nuclear receptors. A single guanine → cytosine replacement in the codon for amino acid 340 resulted in a glycine → arginine substitution in the hormone-binding domain of one of two alleles of the patient's thyroid hormone nuclear receptor β gene. In vitro translation products of this mutant human thyroid hormone nuclear receptor β gene did not bind triiodothyronine. Thus, generalized resistance to thyroid hormone can result from expression of an abnormal thyroid hormone nuclear receptor molecule

Comparison and validation of ELISA assays for plasma insulin-like growth factor-1 in the horse

Directory of Open Access Journals (Sweden)

Courtnay L. Baskerville

2017-03-01

Full Text Available Insulin-like growth factor-1 (IGF-1 plays several important physiological roles, and IGF-related pathways have been implicated in developmental osteochondral disease and endocrinopathic laminitis. This factor is also a downstream marker of growth hormone activity and its peptide mimetics. Unfortunately, previously used assays for measuring equine IGF-1 (radioimmunoassays and ELISAs are no longer commercially available, and many of the kits on the market give poor results when used on horse samples. The aim of the present study was to compare three different ELISA assays (two human and one horse-specific. Plasma samples from six Standardbreds, six ponies and six Andalusians were used. The human IGF-1 ELISA kit from Immunodiagnostic Systems (IDS proved to be the most accurate and precise of the three kits; the other two assays gave apparently much lower concentrations, with poor recovery of spiked recombinant human IGF-1 and unacceptably poor intra-assay coefficients of variation (CV. The IDS assay gave an intra-assay CV of 3.59 % and inter-assay CV of 7.31%. Mean percentage recovery of spiked IGF-1 was 88.82%, and linearity and dilutional parallelism were satisfied. The IGF-1 plasma concentrations were 123.21 ±8.24 ng/mL for Standardbreds, 124.95 ±3.69 ng/mL for Andalusians and 174.26 ±1.94 ng/mL for ponies. Therefore of the three assays assessed, the IGF-1 ELISA manufactured by IDS was the most suitable for use with equine plasma samples and may have many useful applications in several different research areas. However, caution should be used when comparing equine studies where different analytical techniques and assays may have been used to measure this growth factor.

Luteinizing hormone (LH) blood test

Science.gov (United States)

ICSH - blood test; Luteinizing hormone - blood test; Interstitial cell stimulating hormone - blood test ... to temporarily stop medicines that may affect the test results. Be sure to tell your provider about ...

contribution of growth hormone-releasing hormone and

African Journals Online (AJOL)

The strategy used was to stimulate GH secretion in 8 young ... treatment with two oral doses of 50 mg atenolol (to inhibit .... had normal baseline thyroid-stimulating hormone (TSH) ..... production rate of 14% per decade has been documented.'".

Radio-immunoassay of antidiuretic hormone. Choice of a technic of extraction. Normal and pathological values

International Nuclear Information System (INIS)

Basuyau, J.P.; Brunelle, P.; Le Bihan, G.; Bourreille, J.; Bohuon, C.

1980-01-01

The low serum concentration of ADH requires extraction prior to assay. Various methods are compared (direct extraction by acetone, adsorption on talcum powder, Florisil, silicilic acid, Fuller's earth. QUSO, carbon-dextran, adsormone, then elution with hydrochloric acetone). The technic finally used was extraction with Florisil. The antibody used was commercially accessible. The separation of bound from free hormone required a second antibody fixed on Sephadex (DASP). The usual values found in 31 normal subjects from 22 to 89 years were: 7.4 . 4.1 pmol/l(M 2 tau) 1 pmol/l = 1.08 pg/ml. These assays were carried out on tissue extracts prepared by mashing tumour fragments or lymph nodes removed from a patient with the Schwartz Bartter syndrome. They showed the existence in these tissues of high concentrations of ADH immunologically identical with that present in the serum of normal subjects [fr

Evaluation of the amphibian metamorphosis assay: exposure to the goitrogen methimazole and the endogenous thyroid hormone L-thyroxine.

Science.gov (United States)

Coady, Katherine; Marino, Troy; Thomas, Johnson; Currie, Rebecca; Hancock, Gregg; Crofoot, Jackie; McNalley, Lindsay; McFadden, Lisa; Geter, David; Klecka, Gary

2010-04-01

The U.S. Environmental Protection Agency (U.S. EPA) has included an amphibian metamorphosis assay (AMA) to detect thyroid active chemicals in Tier 1 testing of their endocrine screening program. To understand the variability, specificity, and reliability of the key endpoints of this assay, two exposure studies with Xenopus laevis tadpoles were conducted with two known thyroid-active compounds, namely, methimazole or L-thyroxine, for a total of 21 d. In addition, various increased-flow-rate treatments were included in the exposures to evaluate the effects of physical stress on metamorphic development. The endpoints examined in the exposures were wet weight, snout-vent length, hind-limb length, developmental stage, and thyroid and gonadal histopathology. As expected, the results indicated that both methimazole and L-thyroxine were thyroid active in the AMA, hind-limb length and thyroid histopathology being the most sensitive endpoints of thyroid activity. Tadpoles that were exposed to the various physical stressors in these experiments showed no signs of altered metamorphic development, and exposure to the thyroid-active compounds had no effect on the developing gonad of X. laevis. Taken together, these results support the use of the AMA as a Tier 1 endocrine screen for detection of potential thyroid pathway activity; however, the lack of a true negative response (no-effect) during the validation process prevents a full evaluation of this assay's specificity at this time. (c) 2009 SETAC.

Postmenopausal hormone replacement therapy--clinical implications

DEFF Research Database (Denmark)

Ravn, S H; Rosenberg, J; Bostofte, E

1994-01-01

The menopause is defined as cessation of menstruation, ending the fertile period. The hormonal changes are a decrease in progesterone level, followed by a marked decrease in estrogen production. Symptoms associated with these hormonal changes may advocate for hormonal replacement therapy....... This review is based on the English-language literature on the effect of estrogen therapy and estrogen plus progestin therapy on postmenopausal women. The advantages of hormone replacement therapy are regulation of dysfunctional uterine bleeding, relief of hot flushes, and prevention of atrophic changes...... in the urogenital tract. Women at risk of osteoporosis will benefit from hormone replacement therapy. The treatment should start as soon after menopause as possible and it is possible that it should be maintained for life. The treatment may be supplemented with extra calcium intake, vitamin D, and maybe calcitonin...

Hormone therapy and different ovarian cancers

DEFF Research Database (Denmark)

Mørch, Lina Steinrud; Løkkegaard, Ellen; Andreasen, Anne Helms

2012-01-01

Postmenopausal hormone therapy use increases the risk of ovarian cancer. In the present study, the authors examined the risks of different histologic types of ovarian cancer associated with hormone therapy. Using Danish national registers, the authors identified 909,946 women who were followed from...... 1995-2005. The women were 50-79 years of age and had no prior hormone-sensitive cancers or bilateral oophorectomy. Hormone therapy prescription data were obtained from the National Register of Medicinal Product Statistics. The National Cancer and Pathology Register provided data on ovarian cancers......, including information about tumor histology. The authors performed Poisson regression analyses that included hormone exposures and confounders as time-dependent covariates. In an average of 8.0 years of follow up, 2,681 cases of epithelial ovarian cancer were detected. Compared with never users, women...

Optimization of the purification methods for recovery of recombinant growth hormone from Paralichthys olivaceus

Science.gov (United States)

Zang, Xiaonan; Zhang, Xuecheng; Mu, Xiaosheng; Liu, Bin

2013-03-01

This study aimed to optimize the purification of recombinant growth hormone from Paralichthys olivaceus. Recombinant flounder growth hormone (r-fGH) was expressed by Escherichia coli in form of inclusion body or as soluble protein under different inducing conditions. The inclusion body was renatured using two recovery methods, i.e., dilution and dialysis. Thereafter, the refolded protein was purified by Glutathione Sepharase 4B affinity chromatography and r-fGH was obtained by cleavage of thrombin. For soluble products, r-fGH was directly purified from the lysates by Glutathione Sepharase 4B affinity chromatography. ELISA-receptor assay demonstrated that despite its low receptor binding activity, the r-fGH purified from refolded inclusion body had a higher yield (2.605 mg L-1) than that from soluble protein (1.964 mg L-1). Of the tested recovery methods, addition of renaturing buffer (pH 8.5) into denatured inclusion body yielded the best recovery rate (17.9%). This work provided an optimized purification method for high recovery of r-fGH, thus contributing to the application of r-fGH to aquaculture.

Provision of radioimmunoassays for reproductive hormones in developing countries

International Nuclear Information System (INIS)

Sufi, S.B.; Donaldson, A.; Jeffcoate, S.L.; Goncharov, N.P.

1986-01-01

The Special Programme of Research, Development and Research Training in Human Reproduction of the World Health Organization (WHO) has, for the last eight years, distributed sets of matched assay reagents for the radioimmunoassay of hormones to approximately 75 laboratories in 45 countries. The Matched Reagent Programme has enabled these centres to carry out research that would otherwise have been difficult, if not impossible, for them to undertake. Between-centre comparability, as judged by WHO External Quality Assurance Scheme data, has improved and at least five hundred scientific papers have been published as a consequence of the availability of WHO reagents. National and regional reagent programmes and associated schemes are being encouraged. These activities should help to improve the availability of research and diagnostic facilities for patient care in developing countries, which is consistent with the WHO policy of technology transfer. (author)

Radioimmunoassay of steroid hormone

International Nuclear Information System (INIS)

Murakami, Tadashi

1975-01-01

Low acid pepsin treated gamma-globulin was applied to ammonium sulfate salting out method, which was a method to separate bound fraction from free one in radioimmunoassay of steroid hormone, and the effect of the separation and the standard curve were examined. Pepsin treated gamma-globulin was prepared in pH 1.5 to 5.5 and then the pepsin was completely removed. It had an effect to accelerate the precipitation in radioimmunoassay of steroid hormone labelled with 3 H. The effect of pepsin treated gamma-globulin to adhere free steroid hormone and to slat out bound one was compared with that of human gamma-globulin. Pepsin treated gamma-globulin, which was water soluble, could easier reach its optimal concentration, and the separation effect was better than human gamma-globulin. The standard curve of it was steeper, particularly in a small dose, and the reproducibility was also better. It could be applied not only to aldosterone and DOC, but also to the steroid hormones, such as progesterone and DHEA, and it seemed suitable for routine measurement method. (Kanao, N.)

Measurement of the incretin hormones

DEFF Research Database (Denmark)

Kuhre, Rune Ehrenreich; Wewer Albrechtsen, Nicolai Jacob; Hartmann, Bolette

2015-01-01

The two incretin hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP), are secreted from the gastrointestinal tract in response to meals and contribute to the regulation of glucose homeostasis by increasing insulin secretion. Assessment of plasma concentrat......The two incretin hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP), are secreted from the gastrointestinal tract in response to meals and contribute to the regulation of glucose homeostasis by increasing insulin secretion. Assessment of plasma...... concentrations of GLP-1 and GIP is often an important endpoint in both clinical and preclinical studies and, therefore, accurate measurement of these hormones is important. Here, we provide an overview of current approaches for the measurement of the incretin hormones, with particular focus on immunological...

Sex hormone-binding globulin as a marker for the thrombotic risk of hormonal contraceptives.

NARCIS (Netherlands)

Raps, M.; Helmerhorst, F.; Fleischer, K.; Thomassen, S.; Rosendaal, F.; Rosing, J.; Ballieux, B.; Vliet, H. van

2012-01-01

BACKGROUND: It takes many years to obtain reliable values for the risk of venous thrombosis of hormonal contraceptive users from clinical data. Measurement of activated protein C (APC) resistance via thrombin generation is a validated test for determining the thrombogenicity of hormonal

Not all elevated hormones are toxic: A case of thyroid hormone resistance

Directory of Open Access Journals (Sweden)

Rajeev Philip

2016-01-01

Full Text Available Resistance to thyroid hormone syndrome (RTH is a rare disorder and is usually inherited as dominantly negative autosomal trait. RTH is caused by mutations in the thyroid hormone receptor beta. Patients with RTH usually do not have signs and symptoms of thyrotoxicosis, but the thyroid function test shows an elevated T3 and T4, which get misinterpreted as hyperthyroidism, resulting in unnecessary treatment.

SHBG (Sex Hormone Binding Globulin)

Science.gov (United States)

... Links Patient Resources For Health Professionals Subscribe Search Sex Hormone Binding Globulin (SHBG) Send Us Your Feedback ... As Testosterone-estrogen Binding Globulin TeBG Formal Name Sex Hormone Binding Globulin This article was last reviewed ...

Hormone Therapy for Breast Cancer

Science.gov (United States)

... Common Cancer Types Recurrent Cancer Common Cancer Types Bladder Cancer Breast Cancer Colorectal Cancer Kidney (Renal Cell) Cancer ... sensitive breast cancer cells contain proteins called hormone receptors that become activated when hormones bind to them. ...

Determination of the concentration of thyroid hormone in dialysate and assessment of the loss of thyroid hormone during hemodialysis

International Nuclear Information System (INIS)

Beyer, H.K.; Schuster, P.; Pressler, H.; Bochum Univ.

1980-01-01

In order to determine the hormone concentration in a dialysate, the commercially available radioimmunossay test of Dow-Lepetit for determination of free thyroid hormones in serum had to be modified. The results raised the suspicion that additional protein-bound hormone had passed the membrane. This could be demonstrated by the addition of Thiomersal. In 64 patients examined 1 and 5 hrs after the beginning of hemodialysis the mean total hormone concentration in the dialysate was 12.05 pg/ml for thyroxine and 5.47 pg/ml for triiodothyronine. The resulting loss of total hormone in hemodialysis patients, calculated for 1 week, amounted to 2.25 μg triiodothyronine and 4.87 μg thyroxine. The comparison with the physiologic renal elimination of thyroid hormone shows that the hormone elimination in hemodialysis patients is negligibly small. The quantitative determination of the protein concentration in the dialysate however, that the loss of protein is without clinical relevance. (orig.) [de

Pituitary-hormone secretion by thyrotropinomas

NARCIS (Netherlands)

Roelfsema, Ferdinand; Kok, Simon; Kok, Petra; Pereira, Alberto M.; Biermasz, Nienke R.; Smit, Jan W.; Frolich, Marijke; Keenan, Daniel M.; Veldhuis, Johannes D.; Romijn, Johannes A.

2009-01-01

Hormone secretion by somatotropinomas, corticotropinomas and prolactinomas exhibits increased pulse frequency, basal and pulsatile secretion, accompanied by greater disorderliness. Increased concentrations of growth hormone (GH) or prolactin (PRL) are observed in about 30% of thyrotropinomas leading

Long-term outcomes of tissue-based ACTH-antibody assay-guided transsphenoidal resection of pituitary adenomas in Cushing disease.

Science.gov (United States)

Erfe, J Mark; Perry, Avital; McClaskey, John; Inzucchi, Silvio E; James, Whitney Sheen; Eid, Tore; Bronen, Richard A; Mahajan, Amit; Huttner, Anita; Santos, Florecita; Spencer, Dennis

2017-10-13

OBJECTIVE Cushing disease is caused by a pituitary micro- or macroadenoma that hypersecretes adrenocorticotropic hormone (ACTH), resulting in hypercortisolemia. For decades, transsphenoidal resection (TSR) has been an efficacious treatment but with certain limitations, namely precise tumor localization and complete excision. The authors evaluated the novel use of a double-antibody sandwich assay for the real-time quantitation of ACTH in resected pituitary specimens with the goals of augmenting pathological diagnosis and ultimately improving long-term patient outcome. METHODS This study involved a retrospective review of records and an analysis of assay values, pathology slides, and MRI studies of patients with Cushing disease who had undergone TSR in the period from 2009 to 2014 and had at least 1 year of follow-up in coordination with an endocrinologist. In the operating room, biopsy specimens from the patients had been analyzed for tissue ACTH concentration. Additional samples were simultaneously sent for frozen-section pathological analysis. The ACTH assay performance was compared against pathology assessments of surgical tumor samples using receiver operating characteristic (ROC) analysis and against pre- and postoperative MRI studies. RESULTS Fourteen patients underwent TSR with guidance by ACTH-antibody assay and pathological assessment of 127 biopsy samples and were followed up for an average of 3 years. The ACTH threshold for discriminating adenomatous from normal tissue was 290,000 pg/mg of tissue, based on jointly maximized sensitivity (95.0%) and specificity (71.3%). Lateralization discordance between preoperative MRI studies and surgical visualization was noted in 3 patients, confirming the impression that MRI alone may not achieve optimal localization. A majority of the patients (85.7%) attained long-term disease remission based on urinary free cortisol levels, plasma cortisol levels, and long-term corticosteroid therapy. Comparisons of patient

Sex hormones and skeletal muscle weakness

DEFF Research Database (Denmark)

Sipilä, Sarianna; Narici, Marco; Kjaer, Michael

2013-01-01

Human ageing is accompanied with deterioration in endocrine functions the most notable and well characterized of which being the decrease in the production of sex hormones. Current research literature suggests that low sex hormone concentration may be among the key mechanism for sarcopenia...... and muscle weakness. Within the European large scale MYOAGE project, the role of sex hormones, estrogens and testosterone, in causing the aging-related loss of muscle mass and function was further investigated. Hormone replacement therapy (HRT) in women is shown to diminish age-associated muscle loss, loss...... properties. HRT influences gene expression in e.g. cytoskeletal and cell-matrix proteins, has a stimulating effect upon IGF-I, and a role in IL-6 and adipokine regulation. Despite low circulating steroid-hormone level, postmenopausal women have a high local concentration of steroidogenic enzymes in skeletal...

Hormone Replacement Therapy: MedlinePlus Health Topic

Science.gov (United States)

... of hormone therapy (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Hormone Replacement Therapy ... Estrogen overdose Types of hormone therapy Related Health Topics Menopause National Institutes of Health The primary NIH ...

Improvement of reproducibility and quality control of human growth hormone radioiodination

International Nuclear Information System (INIS)

Bartolini, P.; Ribela, M.T.C.P.; Camilo, M.A.

1988-01-01

The labelling reaction of human growth hormone (hGH) with 125 I and its chromatographic purification have been studied with emphasis on the reproducibility of the yields, quantitaTive recoveries and resulting activities. Through the accurate standardization of a monitoring technique, it is confirmed that there are no significant losses in radioactivity or protein during the labelling or purification process. By strict control of the reaction conditions a fairily good reproducibility is also obtained in the labelling of various hGH extracts with diferent 125 I shipments used after short or long storage. Finally, the specific activity (or absolute mass) of the radioiodinated protein is determined by this Analysis of the Reaction Mixture and compared to the widely used radioimmunological assay (Self-displacement). (M.A.C.) [pt

Characterization of the hormone-binding domain of the chicken c-erbA/thyroid hormone receptor protein

DEFF Research Database (Denmark)

Muñoz, A; Zenke, M; Gehring, U

1988-01-01

mutations present in the carboxy-terminal half of P75gag-v-erbA co-operate in abolishing hormone binding, and that the ligand-binding domain resides in a position analogous to that of steroid receptors. Furthermore, a point mutation that is located between the putative DNA and ligand-binding domains of P75......To identify and characterize the hormone-binding domain of the thyroid hormone receptor, we analyzed the ligand-binding capacities of proteins representing chimeras between the normal receptor and P75gag-v-erbA, the retrovirus-encoded form deficient in binding ligand. Our results show that several......gag-v-erbA and that renders it biologically inactive fails to affect hormone binding by the c-erbA protein. These results suggest that the mutation changed the ability of P75gag-v-erbA to affect transcription since it also had no effect on DNA binding. Our data also suggest that hormone...

In vitro invasion of small-cell lung cancer cell lines correlates with expression of epidermal growth factor receptor

DEFF Research Database (Denmark)

Damstrup, L; Rude Voldborg, B; Spang-Thomsen, M

1998-01-01

receptor (EGFR) in a panel of 21 small-cell lung cancer (SCLC) cell lines. We have previously reported that ten of these cell lines expressed EGFR protein detected by radioreceptor and affinity labelling assays. In 11 small-cell lung cancer (SCLC) cell lines, EGFR mRNA was detected by Northern blot...... analysis. In vitro invasion in a Boyden chamber assay was found in all EGFR-positive cell lines, whereas no invasion was detected in the EGFR-negative cell lines. Quantification of the in vitro invasion in 12 selected SCLC cell lines demonstrated that, in the EGFR-positive cell lines, between 5% and 16......-PCR). However, in vitro invasive SCLC cell lines could not be distinguished from non-invasive cell lines based on the expression pattern of these molecules. In six SCLC cell lines, in vitro invasion was also determined in the presence of the EGFR-neutralizing monoclonal antibody mAb528. The addition...

Increasing Goat Productivity Through the Improvement of Endogenous Secretion of Pregnant Hormones Using Follicle Stimulating Hormone

Directory of Open Access Journals (Sweden)

Andriyanto Andriyanto

2011-05-01

Full Text Available Abstract. Previous studies reported that the improvement of endogenous estrogen and progesterone secretions during gestation improved fetal prenatal growth, birth weight, mammary gland growth and development, milk production, litter size, pre- and post-weaning growths. An experiment was conducted to apply the improvement of endogenous secretion of pregnant hormones during pregnancy to increase goat productivity. Thirty-six female ettawah-cross does were divided into 2 groups. Group 1 (control: 18 does included does without improvement of endogenous secretion of pregnant hormones and Group 2 (treatment: 18 does included does with improvement of endogenous secretion of pregnant hormones using follicle stimulating hormones to stimulate super ovulation. The application of this technology increased total offspring born (control: 25 offspring; treatment: 42 offspring, average litter size (control: 1.88; treatment: 2.33, offspring birth weight (control: 2.85±0.50 kg; treatment: 3.82±0.40 kg, and does milk production (control: 1.36±0.34 L/does/day; treatment: 2.10±0.21 L/does/day. Offspring born to does with improved endogenous secretion of pregnant hormones had better weaning weight (control: 11.17±1.99 kg/offspring; treatment: 14.5±1.11 kg/offspring. At weaning period, does with improved endogenous secretion of pregnant hormones produced offspring with total weaning weight twice as heavy as control does (control: 189.9 kg; treatment: 403.6 kg. By a simple calculation of economic analysis, this technology application could increase gross revenue per does until weaning by Rp. 432.888,89. It was concluded that this technology is economically feasible to be applied in small-scale farm. Key Words: follicle stimulating hormone, pregnant hormones, endogenous secretion, super ovulation, ettawah-cross does

Crystal structure of the PAC1R extracellular domain unifies a consensus fold for hormone recognition by class B G-protein coupled receptors.

Directory of Open Access Journals (Sweden)

Shiva Kumar

Full Text Available Pituitary adenylate cyclase activating polypeptide (PACAP is a member of the PACAP/glucagon family of peptide hormones, which controls many physiological functions in the immune, nervous, endocrine, and muscular systems. It activates adenylate cyclase by binding to its receptor, PAC1R, a member of class B G-protein coupled receptors (GPCR. Crystal structures of a number of Class B GPCR extracellular domains (ECD bound to their respective peptide hormones have revealed a consensus mechanism of hormone binding. However, the mechanism of how PACAP binds to its receptor remains controversial as an NMR structure of the PAC1R ECD/PACAP complex reveals a different topology of the ECD and a distinct mode of ligand recognition. Here we report a 1.9 Å crystal structure of the PAC1R ECD, which adopts the same fold as commonly observed for other members of Class B GPCR. Binding studies and cell-based assays with alanine-scanned peptides and mutated receptor support a model that PAC1R uses the same conserved fold of Class B GPCR ECD for PACAP binding, thus unifying the consensus mechanism of hormone binding for this family of receptors.

Structure-activity relationship of crustacean peptide hormones.

Science.gov (United States)

Katayama, Hidekazu

2016-01-01

In crustaceans, various physiological events, such as molting, vitellogenesis, and sex differentiation, are regulated by peptide hormones. To understanding the functional sites of these hormones, many structure-activity relationship (SAR) studies have been published. In this review, the author focuses the SAR of crustacean hyperglycemic hormone-family peptides and androgenic gland hormone and describes the detailed results of our and other research groups. The future perspectives will be also discussed.

Analysis of sex hormones in groundwater using electron impact ionization

International Nuclear Information System (INIS)

Gonschorowski, Graciele Pereira da Cruz; Gonschorowski, Juliano dos Santos; Shihomatsu, Helena M.; Bustillos, Jose Oscar Vega; Limeira, Larissa

2013-01-01

A wide range of estrogenic contaminants has been detected in the aquatic environment, both in natural and synthetic forms. Steroid hormones are endocrine-disrupting compounds, which affect the endocrine system at very low concentrations. This work presents the development of an analytical procedure for the determination of five sexual steroid hormones, 17β-estradiol, estrone, progesterone, and the synthetics contraceptives, 17α-ethynylestradiol and norgestrel in groundwater from Sao Paulo University campus, specifically at Institute of Energy and Nuclear Research (IPEN). The analytical procedure starting with the sample pre-treatment, where the samples were first filtered and then extracted through solid-phase extraction, using Strata-X cartridges, and ending with detection. The separation method used was gas chromatography (GC), and the detection method was mass spectrometry (MS). The ion source used was electron impact ionization which produced an electron beam generated by an incandescent tungsten/thorium filament, which collide with molecules of gas sample. This interaction between the electrons and molecules, produce ions of the sample. The detection limits 0.06μg.L -1 for estrone, 0.13 μg. L -1 for 17β-estradiol, 0.13 μg.L -1 for 17α-ethynylestradiol, 0.49 μg.L -1 for norgestrel and 0.02 μg.L -1 for progesterone were detected in assays matrix. Validating tests were also used in this work. (author)

Fluorochemicals used in food packaging inhibit male sex hormone synthesis

Energy Technology Data Exchange (ETDEWEB)

Rosenmai, A.K., E-mail: akjro@food.dtu.dk [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Nielsen, F.K. [Section of Toxicology, Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2100 Copenhagen (Denmark); Pedersen, M. [Division of Food Chemistry, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Hadrup, N. [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Trier, X. [Division of Food Chemistry, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark); Christensen, J.H. [Department of Basic Sciences and Environment, Faculty of Life Sciences, University of Copenhagen, DK-1871 Frederiksberg C. (Denmark); Vinggaard, A.M. [Division of Toxicology and Risk Assessment, National Food Institute, Technical University of Denmark, DK-2860 Søborg (Denmark)

2013-01-01

Polyfluoroalkyl phosphate surfactants (PAPS) are widely used in food contact materials (FCMs) of paper and board and have recently been detected in 57% of investigated materials. Human exposure occurs as PAPS have been measured in blood; however knowledge is lacking on the toxicology of PAPS. The aim of this study was to elucidate the effects of six fluorochemicals on sex hormone synthesis and androgen receptor (AR) activation in vitro. Four PAPS and two metabolites, perfluorooctanoic acid (PFOA) and 8:2 fluorotelomer alcohol (8:2 FTOH) were tested. Hormone profiles, including eight steroid hormones, generally showed that 8:2 diPAPS, 8:2 monoPAPS and 8:2 FTOH led to decreases in androgens (testosterone, dehydroepiandrosterone, and androstenedione) in the H295R steroidogenesis assay. Decreases were observed for progesterone and 17-OH-progesterone as well. These observations indicated that a step prior to progestagen and androgen synthesis had been affected. Gene expression analysis of StAR, Bzrp, CYP11A, CYP17, CYP21 and CYP19 mRNA showed a decrease in Bzrp mRNA levels for 8:2 monoPAPS and 8:2 FTOH indicating interference with cholesterol transport to the inner mitochondria. Cortisol, estrone and 17β-estradiol levels were in several cases increased with exposure. In accordance with these data CYP19 gene expression increased with 8:2 diPAPS, 8:2 monoPAPS and 8:2 FTOH exposures indicating that this is a contributing factor to the decreased androgen and the increased estrogen levels. Overall, these results demonstrate that fluorochemicals present in food packaging materials and their metabolites can affect steroidogenesis through decreased Bzrp and increased CYP19 gene expression leading to lower androgen and higher estrogen levels. -- Highlights: ► Fluorochemicals found in 57% of paper and board food packaging were tested. ► Collectively six fluorochemicals were tested for antiandrogenic potential in vitro. ► Three out of six tested fluorochemicals inhibited

Network identification of hormonal regulation.

Directory of Open Access Journals (Sweden)

Daniel J Vis

Full Text Available Relations among hormone serum concentrations are complex and depend on various factors, including gender, age, body mass index, diurnal rhythms and secretion stochastics. Therefore, endocrine deviations from healthy homeostasis are not easily detected or understood. A generic method is presented for detecting regulatory relations between hormones. This is demonstrated with a cohort of obese women, who underwent blood sampling at 10 minute intervals for 24-hours. The cohort was treated with bromocriptine in an attempt to clarify how hormone relations change by treatment. The detected regulatory relations are summarized in a network graph and treatment-induced changes in the relations are determined. The proposed method identifies many relations, including well-known ones. Ultimately, the method provides ways to improve the description and understanding of normal hormonal relations and deviations caused by disease or treatment.

Fiscal 1997 report on the results of the international standardization R and D. Measurement of ultra-micro chemical substances and measuring methods of hormone effects; 1997 nendo seika hokokusho kokusai hyojun soseigata kenkyu kaihatsu. Chobiryo kagaku busshitsu no keisoku horumon eikyo sayo sokuteiho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

Concerning the measurement system of ultra-micro hazardous chemical substances in the global environment, the paper examined the present situation of chemical substances such as dioxins, made an experimental study on the method to analyze dioxins in exhaust gas from an aspect of international consistency, and worked out a JIS draft. As to the standard measuring method of hormone effects of chemical substances, the paper developed the competitive bonding experiment system to measure bonding ability of chemical substances to homo sapiens estrogen receptor (ER). By measuring ER bonding ability of 78 kinds of chemical substances, the measuring method was developed. In the development of the assay system for detection of hormone-like compounds, the assay system with transfer activity via estrogen receptor as an index was established using cultured cells and yeast. Further, the development was made of a measuring method of receptor bonding activity of hormone-like substances. 33 refs., 151 figs., 66 tabs.

Sex Hormones and Ischemic Stroke

DEFF Research Database (Denmark)

Holmegard, Haya N; Nordestgaard, Børge G; Jensen, Gorm B

2016-01-01

CONTEXT AND OBJECTIVE: Whether endogenous sex hormones are associated with ischemic stroke (IS) is unclear. We tested the hypothesis that extreme concentrations of endogenous sex hormones are associated with risk of IS in the general population. DESIGN, SETTING, AND PARTICIPANTS: Adult men (n...... = 4615) and women (n = 4724) with measurements of endogenous sex hormones during the 1981-1983 examination of the Copenhagen City Heart Study, Denmark, were followed for up to 29 years for incident IS, with no loss to follow-up. Mediation analyses assessed whether risk of IS was mediated through...

Free thyroid hormones in health and disease

International Nuclear Information System (INIS)

Bueber, V.

1984-01-01

Several groups of patients with normal and abnormal thyroid function as well as patients with goitre on hormone substitution are discussed with respect to the diagnostic value of the free thyroid hormone methods. The free T 3 technique under investigation separates clearly between euthyroidism and hyperthyroidism, however, during application of contraceptive pills and during pregnancy free T 3 is slightly enhanced. Free T 4 can be found in the normal range even in hypothyroidism, during T 4 substitution free T 4 is useful for control of adequate hormone substitution. Free thyroid hormones are advantageous to be performed with respect to practicability compared to the estimation of total hormone concentrations by enzyme as well as radioimmunoassay. Normally there is no additional demand for measurement of thyroid hormone binding proteins, another rather economical argument for using these parameters in thyroid diagnosis. (orig.) [de

Radioimmunological and clinical studies with luteinizing hormone releasing hormone (LRH)

International Nuclear Information System (INIS)

Dahlen, H.G.

1986-01-01

Radioimmunoassay for Luteinizing Hormone Releasing Hormone (LRH) has been established, tested and applied. Optimal conditions for the performance with regards to incubation time, incubation temperature, concentration of antiserum and radiolabelled LRH have been established. The specificity of the LRH immunoassay was investigated. Problems with direct measurement of LRH in plasmas of radioimmunoassay are encountered. The LRH distribution in various tissues of the rat are investigated. By means of a system for continuous monitoring of LH and FSH in women the lowest effective dose of LRH causing a significant release of LH and FSH could be established. (Auth.)

Incretin hormone secretion over the day

DEFF Research Database (Denmark)

Ahren, B; Carr, RD; Deacon, Carolyn F.

2010-01-01

The two incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are key factors in the regulation of islet function and glucose metabolism, and incretin-based therapy for type 2 diabetes has gained considerable interest during recent years. Regulat......The two incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are key factors in the regulation of islet function and glucose metabolism, and incretin-based therapy for type 2 diabetes has gained considerable interest during recent years....... Regulation of incretin hormone secretion is less well characterized. The main stimulus for incretin hormone secretion is presence of nutrients in the intestinal lumen, and carbohydrate, fat as well as protein all have the capacity to stimulate GIP and GLP-1 secretion. More recently, it has been established...... that a diurnal regulation exists with incretin hormone secretion to an identical meal being greater when the meal is served in the morning compared to in the afternoon. Finally, whether incretin hormone secretion is altered in disease states is an area with, so far, controversial results in different studies...

Highly potent metallopeptide analogues of luteinizing hormone-releasing hormone

International Nuclear Information System (INIS)

Bajusz, S.; Janaky, T.; Csernus, V.J.; Bokser, L.; Fekete, M.; Srkalovic, G.; Redding, T.W.; Schally, A.V.

1989-01-01

Metal complexes related to the cytotoxic complexes cisplatin [cis-diamminedichloroplatinum(II)] and transbis(salicylaldoximato)copper(II) were incorporated into suitably modified luteinizing hormone-releasing hormone (LH-RH) analogues containing D-lysine at position 6. Some of the metallopeptides thus obtained proved to be highly active LH-RH agonists or antagonists. Most metallopeptide analogues of LH-RH showed high affinities for the membrane receptors of rat pituitary and human breast cancer cells. Some of these metallopeptides had cytotoxic activity against human breast cancer and prostate cancer and prostate cancer cell lines in vitro. Such cytostatic metallopeptides could be envisioned as targeted chemotherapeutic agents in cancers that contain receptors for LH-RH-like peptides

Effects of hormones on platelet aggregation.

Science.gov (United States)

Farré, Antonio López; Modrego, Javier; Zamorano-León, José J

2014-04-01

Platelets and their activation/inhibition mechanisms play a central role in haemostasis. It is well known agonists and antagonists of platelet activation; however, during the last years novel evidences of hormone effects on platelet activation have been reported. Platelet functionality may be modulated by the interaction between different hormones and their platelet receptors, contributing to sex differences in platelet function and even in platelet-mediated vascular damage. It has suggested aspects that apparently are well established should be reviewed. Hormones effects on platelet activity are included among them. This article tries to review knowledge about the involvement of hormones in platelet biology and activity.

Anti-Müllerian hormone and polycystic ovary syndrome.

Science.gov (United States)