Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0432222 (SEM)
47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to assess the effect of sex steroids on bone mineral density in Japanese with senile osteoporosis, the bone mineral density in 1/3 distal site of radius was measured serially before and after treatment for 2 years using single photon absorptiometry. Sixty seven old females with senile osteoporosis were divided into 4 groups, Group 1 (n = 28, mean age; 74.4 +/- 1.3 y.o., mean +/- SEM) was the control group, Group 2 (n = 14, mean age; 73.7 +/- 1.7 y.o.) was treated with 0.5-1.0 micrograms/day of 1 alpha -OHD3, Group 3 (n = 12, mean age; 75.4 +/- 2.9 y.o.) was treated with conjugated estrogen (Premarin) in a dose of 0.3125 mg/day (3 approximately 4 weeks administration followed by 1 week rest) and Group 4 (n = 13, mean age; 76.4 +/- 1.8 y.o.) was treated with sex-steroids (pregnenolone : androstenedione : androstenediol : testosterone : estrone = 1.0 mg : 1.0 mg : 0.5 mg : 0.1 mg : 5 micrograms/tablet) and thyroid hormone (thyroid-sicca 7.5 mg/tablet) preparation in a dose of 2 tablets/day. When the radial bone mineral density (RMD) before the treatment was taken as 100%, RMDs of each group at 6, 12, 18 and 24 months were 96.4 +/- 3.1%, 97.3 +/- 2.0%, 93.7 +/- 2.1% and 96.1 +/- 1.8% in Group 1, 100.8 +/- 2.8%, 106.4 +/- 2.1%, 101.3 +/- 3.4% and 108.8 +/- 2.9% in Group 2, 103.0 +/- 2.8%, 106.2 +/- 3.5%, 105.9 +/- 4.3% and 100.2 +/- 4.7% in Group 3, 105.3 +/- 2.2%, 104.7 +/- 2.3%, 112.6 +/- 6.4% and 112.1 +/- 6.7% in Group 4, respectively. Therefore, significant increases in RMD were observed in Groups 2, 3 (transient) and 4 when compared with Group 1. In Group 3, serum level of parathyroid hormone (PTH) was significantly (p less than 0.05) increased from 0.28 +/- 0.03 ng/ml before the treatment to 0.55 +/- 0.15 ng/ml at 24 months after the treatment. In Group 2, transient (6 months after the treatment) but significant (p less than 0.01) increase in urinary Ca/Creatinine ratio from 0.15 +/- 0.04 to 0.20 +/- 0.03 was found. Serum A1-P activities in Group 4 was shown to increase transiently from 131 +/- 10 IU to 151 +/- 12 IU (p less than 0.05) at 6 months and to 158 +/- 13 IU (p less than 0.01) at 12 months followed by subsequent decrease to 135 +/- 6 IU at 18 months and 133 +/- 10 IU at 24 months after the treatment.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:[The effect of estrogen and, sex-steroids and thyroid hormone preparation on bone mineral density in senile osteoporosis--a comparative study of the effect of 1 alpha-hydroxycholecalciferol (1 alpha-OHD3) on senile osteoporosis]. 164 79

Metabolic balance studies were carried out to determine the interrelationships of thyroid hormone-induced lipogenesis, lipolysis, and energy balance in the free-living rat. Intraperitoneal doses of 15 micrograms triiodothyronine (T3)/100 g body wt per d caused an increase in caloric intake from 26.5 +/- 1.7 (mean +/- SEM) kcal/100 g per d to 38.1 +/- 1.5 kcal/100 g per d. Food intake, however, rose only after 4-6 d of treatment and was maximal by the 8th day. In contrast, total body basal oxygen consumption rose by 24 h and reached a maximum by 4 d. Since total urinary nitrogen excretion and hepatic phosphoenolpyruvate carboxykinase mRNA did not rise, gluconeogenesis from protein sources did not supply the needed substrate for the early increase in calorigenesis. Total body fat stores fell approximately 50% by the 6th day of treatment and could account for the entire increase in caloric expenditure during the initial period of T3 treatment. Total body lipogenesis increased within 1 d and reached a plateau 4-5 d after the start of T3 treatment. 15-19% of the increased caloric intake was channeled through lipogenesis, assuming glucose to be the sole substrate for lipogenesis. The metabolic cost of the increased lipogenesis, however, accounted for only 3-4% of the T3-induced increase in calorigenesis. These results suggest that fatty acids derived from adipose tissue are the primary source of substrate for thyroid hormone-induced calorigenesis and that the early increase in lipogenesis serves simply to maintain fat stores. Since the mRNAs coding for lipogenic enzymes rise many hours before oxygen consumption and lipolysis, these results suggest that T3 acts at least in part by an early coordinate induction of the genes responsible for these processes.
...
PMID:Functional relationship of thyroid hormone-induced lipogenesis, lipolysis, and thermogenesis in the rat. 198 90

We have studied serum concentrations of immunoassayable tumor necrosis factor-alpha (TNF alpha) and iodothyronines (T4, T3, and rT3) in normal subjects (n = 16) and patients with nonthyroidal illnesses (NTI; n = 13), hyperthyroidism (n = 10), and hypothyroidism (n = 9). The mean (+/- SEM; femtomoles per mL) serum concentration of TNF alpha was 45 +/- 4.3 in normal subjects, 84 +/- 38 in NTI, 54 +/- 6.0 in hyperthyroidism, and 50 +/- 10 in hypothyroidism; the various values did not differ significantly from one another. Serum TNF alpha was well within the normal range in all NTI patients, except one patient with a brain glioma and infection in whom it was elevated (540 fmol/mL). There was no significant correlation between serum TNF alpha and serum T4, T3, or rT3 levels in NTI patients. Similarly, there was no correlation between serum TNF alpha and serum thyroid hormone (T3 or T4) levels when data in normal subjects were combined with those in NTI patients. The dialyzable fraction of T3 and the free T3 concentration did not correlate with serum TNF alpha levels. However, there was a tendency toward a positive correlation between dialyzable fraction of T4 and the serum concentration of TNF alpha in NTI (r = 0.54; n = 11; 0.05 greater than P less than 0.1). The relationship between these two parameters became more clear when data in normal subjects and NTI patients were combined for statistical analysis (r = 0.59; n = 22; P less than 0.005). The free T4 concentration correlated positively with serum TNF alpha levels whether the data in NTI patients were analyzed alone (r = 0.93; P less than 0.001) or in combination with data from normal subjects (r = 0.85; P less than 0.001). Our data suggest that circulating TNF alpha may contribute to elevated free T4 in NTI. However, it is not a universal or common factor in the pathogenesis of other alterations in serum thyroid hormone levels in NTI (euthyroid sickness syndrome).
...
PMID:A study of the serum concentration of tumor necrosis factor-alpha in thyroidal and nonthyroidal illnesses. 202 11

Calcitonin has an uncertain role in the preservation of bone mass. Since surgical thyroidectomy abolishes the calcitonin secretion in response to calcium, the bone mineral density at the radius shaft and lumbar spine was measured in 60 patients (5 men, 16 premenopausal, 34 postmenopausal euparathyroid and 5 postmenopausal hypoparathyroid women) who had undergone near total thyroidectomy for thyroid cancer 8.4 +/- 0.7 years before the study. All patients were maintained on suppressive doses of thyroid hormones. Bone mineral density values of the radius shaft (expressed as Z-score) of 34 postmenopausal euparathyroid women was significantly below the normal average (mean +/- SEM = -0.59 +/- 0.2; p = 0.01). Bone mineral density of the lumbar spine was also below the normal average although the difference only approached statistical significance (-0.36 +/- 0.2; 0.05 less than p less than 0.1). The bone mineral density of neither the radius nor the spine differed from normal levels in the premenopausal women and the postmenopausal hypoparathyroid women. Unexpectedly, the bone mineral density of the spine was significantly increased in the 5 thyroidectomized men. The results indicate that thyroidectomized women have a diminished bone mass after the menopause only if parathyroid function is normal. Since the patients were receiving thyroid hormone at suppressive doses, the present study is not able to separate the relative contributions of calcitonin deficit and exogenous thyroid on bone mass loss.
...
PMID:Bone mass in totally thyroidectomized patients. Role of calcitonin deficiency and exogenous thyroid treatment. 202 10

Severe combined immunodeficient (SCID) mice were injected with peripheral blood mononuclear cells (PBMC) from normal individuals and 14 out of 18 had detectable serum human (h) IgG (maximum levels providing a mean +/- SEM 934 +/- 213 micrograms/ml) and IgM (253 +/- 93 micrograms/ml) at 3-6 weeks after transplantation. Serum human immunoglobulin levels were maximum 6-12 weeks after transplantation and declined to low levels over the subsequent 5 months. Human B cells constituted up to 10% and human T cells up to 40% of cells in the peripheral circulation and spleens of these animals 2-3 weeks after transplantation, PBMC, or intrathyroidal (IT) lymphocytes, from 6 patients with Graves' disease and high serum levels of thyroid autoantibodies were transplanted into 30 SCID mice (Graves' SCID-hu). Although serum human immunoglobulins were observed in only low amounts in the animals receiving IT lymphocytes (n = 4), increased levels of hIgG or hIgM were more easily detectable in 19 Graves' SCID-hu mice that received PBMC. The Graves' SCID-hu mice had significantly lower mean levels of hIgG and hIgM than those observed following transplantation of normal PBMC (mean maximum 328 +/- 113 and 32 +/- 21 micrograms/ml, respectively). Six of these 19 mice had detectable human autoantibody to thyroid peroxidase (TPO, as microsomal antigen) between 3 and 8 weeks after transplantation, with titers ranging from 0.05 to 0.39 (normal SCID-hu serum less than 0.02 ELISA Index). No abnormal thyroid hormone (T4 and T3) levels or thyroiditis was seen when compared to normal SCID-hu mice. Immunization of reconstituted SCID mice with recombinant immunoactive human TPO antigen failed to initiate anti-TPO in normal PBMC-treated mice nor did it increase the titer of human anti-TPO in the anti-TPO positive animals. In conclusion we successfully established human thyroid autoantibody secretion in the SCID-hu mouse and characterized the transient nature of the model. Further studies will be required to achieve successful antigen presentation in this system.
...
PMID:The SCID-hu mouse and thyroid autoimmunity: characterization of human thyroid autoantibody secretion. 207 May 73

Calcitonin (CT) deficiency and its possible repercussions on bone mass were studied in a group of 9 adult patients (7 females, 2 males) with congenital hypothyroidism of dysgenetic origin. Using a new extraction method (exCT) which considerably improves the sensitivity and the specificity of the assay for CT-monomer, we measured CT levels before and after a short calcium (Ca) stimulation test (2 mg Ca/kg over 5 minutes) to evaluate C-cell secretory reserve. Mean basal plasma CT concentrations were lower in the hypothyroid women (mean +/- SEM: 0.6 +/- 0.1 pg/ml) than in 30 normal female controls (1.7 +/- 0.2 pg/ml, P less than 0.001). Serum calcium increased similarly in the two groups, but postinfusion CT levels were lower in the hypothyroid women, (1.7 +/- 0.2 pg/ml) than in normal women (16.8 +/- 2.9 pg/ml), P less than 0.001. Hypothyroid women showed a 10% reduction in bone mineral content at the diaphyseal site in the radius, 0.840 +/- 0.037 g/cm, compared with normal age-matched controls, 0.930 +/- 0.020 g/cm, (P less than 0.05). Our study demonstrates the existence of a profound CT-monomer deficiency in adult patients with thyroid agenesis or dysgenesis. Both calcitonin deficiency and thyroid hormone treatment could play a role in the observed bone loss. Attention should therefore be paid to bone metabolism during treatment of congenital hypothyroidism to avoid further bone loss.
...
PMID:Calcitonin and bone mass status in congenital hypothyroidism. 193 88

The relationship between thyroid function and serum osteocalcin was studied in a population of 27 women with multinodular goitre and normal serum concentrations of thyroid hormones. Seven patients were found to have suppressed TSH levels (less than 0.1 mU/l) as measured by an immunoradiometric assay. Osteocalcin was statistically significantly correlated with serum free thyroxine (FT4), both in the total population and in the subpopulation of patients with TSH greater than or equal to 0.1 mU/l (r = 0.61; P less than 0.001, resp. r = 0.51; P less than 0.05). Mean (+/- SEM) serum osteocalcin and FT4 were higher in the patients with suppressed TSH than in those with TSH greater than or equal to 0.1 mU/l (10.6 +/- 1.9 vs. 7.1 +/- 0.6 micrograms/l; P less than 0.05, resp. 16.3 +/- 1.4 vs. 13.3 +/- 0.5 pmol/l; P less than 0.02). This study suggests that women with multinodular goitre who proceed to autonomous function are at risk of developing osteoporosis even when thyroid hormone concentrations are in the normal range.
...
PMID:Is there a relationship between thyroid function and serum osteocalcin in women with multinodular goitre? A preliminary report. 221 27

1. We studied a brominated thyroid hormone analogue, SKF L-94901, which has the potential to lower serum cholesterol without adverse cardiovascular effects. This compound is about 50% as active as tri-iodothyronine (T3) in liver nuclear receptor binding in vivo but only 1% as active in vitro and has nearly 200 times more enzyme-inducing activity in liver than in heart. Our aim was to examine the interaction of SKF L-94901 with [125I]T3 binding to the intact nuclei in whole cells, isolated nuclei and nuclear extracts of human HeLa cells and to investigate the binding of this compound to human serum. 2. Relative to thyroxine (T4), the affinity of this compound for T4-binding globulin was 0.0035%, for transthyretin 1.66% and for albumin 1.26%. Low affinity for serum proteins, with a relatively high circulating free fraction, could explain why SKF L-94901 is more potent in vivo than in vitro. 3. Human HeLa cell nuclei, isolated after whole-cell incubations, bound [125I]T3 with high affinity (Kd = 78 +/- 8 pmol/l, mean +/- SEM), which was displaceable by T3 analogues in the order Triac [( 4-(4-hydroxy-3-iodophenoxy)-3,5-di-iodophenyl]acetic acid) greater than T3 greater than T4 much greater than reverse T3. Similar high-affinity (Kd = 58 +/- 6 pmol/l, mean +/- SEM) and identical specificity was observed in high-salt (0.4 mol/l KCl) nuclear extracts. In nuclei of whole cells incubated with [125I]T3 and SKF L-94901, the analogue was 0.8% as potent as T3, whereas in experiments with nuclear extract, the analogue was 7.7% as potent as T3.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:The thyroid hormone analogue SKF L-94901: nuclear occupancy and serum binding studies. 272 Nov 16

The so-called "low T3 syndrome" has frequently been reported in patients with cirrhosis. In this study, we aimed to determine whether administration of propranolol to such patients leads to further changes in plasma thyroid hormones, since it can affect their peripheral metabolism. Twenty cirrhotics (11 with ascites) whom we investigated showed no clinical evidence of thyroid dysfunction. The free fractions of plasma T3 and T4 (FT3, FT4) were determined by radioimmunoassay before and after the achievement of an effective beta-blockade by propranolol. The activity of the sympathetic nervous system also was evaluated by measuring plasma norepinephrine concentration. Under basal conditions, cirrhotics showed a reduced FT3 (2.45 +/- 0.11 SEM vs 3.55 +/- 0.16 pg/ml; p less than 0.001) and comparable FT4 (7.62 +/- 0.79 vs 9.2 +/- 0.42 pg/ml) and FT3/FT4 ratio (0.38 +/- 0.04 vs 0.42 +/- 0.013) with respect to healthy controls. When patients with ascites were considered apart, a reduction of FT4 was also found (6.78 +/- 0.74 pg/ml; p less than 0.01). In these patients, many of whom showed an increased plasma norepinephrine concentration, an inverse correlation between log FT3/FT4 and log plasma norepinephrine concentration was found (r = -0.79; p less than 0.01). The effective beta-blockade did not lead to significant changes in either FT3 or FT4 or FT3/FT4, whether the patients were considered as a whole (2.52 +/- 0.19 pg/ml, 9.3 +/- 1.41 pg/ml, and 0.36 +/- 0.04, respectively), or were split into groups according to the presence of ascites. When administered to cirrhotics, propranolol did not worsen thyroid hormone abnormalities, thus appearing to be safe in this respect. This may result from an impaired influence of the sympathoadrenergic system on thyroid hormone metabolism.
...
PMID:"Low T3 syndrome" in cirrhosis: effect of beta-blockade. 278

The maximal binding capacity (MBC) of the rat cerebrocortical nuclear T3 receptor, as determined by in vivo saturation techniques, is approximately half that measured in vitro on isolated nuclei or solubilized receptors. To investigate this disparity, the MBC values determined in vivo and in vitro for both rat cerebral cortex and liver were compared, taking into account nuclear receptor loss or inactivation and the presence of endogenous T3. By Scatchard analysis of T3 binding to isolated nuclei in vitro at 37 C, the uncorrected MBC values (mean +/- SEM; n = 3) for the cerebrocortical nuclear T3 receptor in euthyroid and hypothyroid rats were 0.80 +/- 0.14 and 0.66 +/- 0.07 ng T3/mg DNA, respectively, and were not significantly different. The Kd values were also not significantly different (5.6 +/- 0.3 and 5.2 +/- 0.9 X 10(-10) M, respectively). After corrections for incomplete dissociation and receptor inactivation under the in vitro conditions, the overall mean MBC increased by approximately 33% to 0.97 ng T3/mg DNA, or about 3.6 times the in vivo MBC. In addition, cerebrocortical nuclei prelabeled in vivo with +/- 131I]T3 at near-saturating levels and subsequently incubated with [125I]T3 in vitro at concentrations up to 10 times the Kd were shown to bind as much as 4 times more T3 in vitro relative to the amount of endogenous hormone which dissociated, thus exceeding the in vivo MBC by a factor of two. Parallel experiments with isolated liver nuclei did not show the existence of nuclear T3 receptors which were available only in vitro, even when the corrected MBC (0.77 ng T3/mg DNA) was compared with the MBC obtained by the in vivo saturation technique (0.76 ng T3/mg DNA). The experiments with liver nuclei were done at 25 C to reduce the rate of inactivation or loss of nuclear T3 receptors in this tissue. By fractionating isolated cerebrocortical nuclei into neuronal and glial subpopulations on discontinuous sucrose gradients, the high affinity, limited capacity nuclear T3 receptor could only be identified in the neuronal fraction. No consistent specific binding of T3 was observed in glial nuclei that were 80% pure, suggesting that either glial cells in the adult rat are not likely to be direct targets of thyroid hormone or that thyroid hormone may act via nonnuclear receptor-mediated pathways. We conclude that only neurons have specific high affinity, limited capacity nuclear T3 receptors and that as many as half of these receptors may not be accessible to plasma T3.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:In vitro 3,5,3'-triiodothyronine binding to rat cerebrocortical neuronal and glial nuclei suggests the presence of binding sites unavailable in vivo. 298 67


<< Previous 1 2 3 4 5 6 7 8 9 Next >>