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Biomedical subjects

G Tarján

Publications and source records attributed to G Tarján.

At least 19 recordsLinked to original sources

[Zn-content of erythrocytes in overt and subclinical hyperthyroidism].

Assaying the markers in blood reflecting thyroid hormone effect at peripheral tissue level previous data revealing a significantly decreased red-blood cell Zn-content in overt hyperthyroidism compared to euthyroid controls could be confirmed (p < 0.001). In patients with thyrotoxicosis during Metothyrin treatment the Zn-concentration of red-blood-cells normalised about 8 weeks later than the abnormally elevated serum thyroxine and triiodothyronine levels. On the basis of the present findings it is assumed that the Zn-concentration of red-blood cells reflects to a certain degree the circulating levels of thyroid hormones 2 to 3 months prior to the performed examination. The measurement of red-blood cell Zn-content does not seem to be a reliable method for the detection of a possible "tissue"-thyrotoxicosis in cases of subclinical hyperthyroidism.

Erythrocytes↗

[Changes in osteocalcin serum levels in children with growth hormone deficiency during substitution therapy].

UNLABELLED: Osteocalcin (OC), a specific marker of osteoblast activity, was measured in 21 short, growth hormone deficient (GHD) children before and during 2 years of growth hormone (GH) therapy. Anthropometric and serum measurements were performed in every three-month during the first year (15 patients) and after the second year (16 patients). Mean OC concentration was significantly lower in GHD children compared to normal value (11.9 +/- 2.1 ng/ml (n = 15) and 11.4 +/- 2.5 ng/ml (n = 16) vs. 17.5 +/- 4.9 ng/ml). During the GH treatment serum OC increased continuously: 15.5 +/- 2.4 - 20.5 +/- 8.2 - 26.1 +/- 8.6 - 25.1 +/- 9.8 ng/ml (n = 15) and 24.9 +/- 9.1 ng/ml (n = 16) then decreased (16.6 +/- 9.7 ng/ml). OC level measured in the 9th and 12th months was markedly higher than in normal children (p = 0.01 and p < 0.001). IN CONCLUSION: 1. Serum OC is low in short statured GHD children. 2. In the first 9-12 months of GH therapy OC raises continuously exceeding the normal mean value. 3. During the second year of GH treatment OC decreases to the normal level. 4. OC concentration measured does not correlate with change of other parameters observed (growth velocity, bone maturation, height for age). 5. Although OC is a sensitive marker of bone formation, it has no prognostic value concerning the growth.

Adolescent↗

Bone mineral density in patients with endogenous subclinical hyperthyroidism: is this thyroid status a risk factor for osteoporosis?

OBJECTIVE: The aim of the present study was to elucidate whether endogenous subclinical hyperthyroidism due to a solitary autonomously functioning thyroid nodule affects bone metabolism and is a risk factor for osteoporosis. DESIGN: In a cross-sectional study measurements of bone mineral density were performed in premenopausal and post-menopausal women. Patients were categorized into non-toxic nodular goitre (n = 32), subclinical hyperthyroid (n = 37) and toxic solitary autonomous thyroid nodule (n = 22) subgroups and the results were compared with those of sex and age-matched control reference population (n = 68). MEASUREMENTS: Lumbar spine and femoral neck bone mineral densities were measured by dual energy X-ray absorptiometry. Single-photon absorptiometry was applied to the measurement of bone mineral content in the midshaft of the radius. RESULTS: In the non-toxic nodular goitre group, bone densities for all the scanned sites did not differ from the sex and age-matched reference population. At the L2-4 scanning site a significant decrease in the bone mineral density could be observed only in the toxic nodular goitre group and this decrease was more marked in the postmenopausal (P < 0.001) than in the premenopausal females (P < 0.05). At the femoral neck and midshaft radius the mean densitometric values were slightly, but significantly, lower only in the post-menopausal subclinical hyperthyroid group compared with the reference population (P < 0.01). The bone mineral density of the femoral neck, as well as the bone mineral content of the midshaft radius, was significantly decreased in both the premenopausal and post-menopausal patients with a toxic solitary nodule. CONCLUSION: This study indicates that the bone mineral density of the lumbar spine, femoral neck and the midshaft of the radius are not significantly decreased in premenopausal patients with endogenous subclinical hyperthyroidism resulting from a solitary autonomously functioning thyroid nodule. Conversely, findings hint at the possibility that long-lasting endogenous subclinical hyperthyroidism may be a contributing factor to the development of osteoporosis in some post-menopausal women, mostly at sites where cortical bone preponderates.

Adult↗

Biologic markers in blood reflecting thyroid hormone effect at peripheral tissue level in patients receiving levothyroxine replacement for hypothyroidism.

Plasma fibronectin, serum procollagen-III-peptide and sex-hormone binding globulin as not specific markers of thyroid hormone effect at peripheral tissue level were determined and their values were related with serum levels of TSH, free-thyroxine and triiodothyronine during levothyroxine sodium replacement therapy for hypothyroidism. Low levels of biologic markers characteristic of hypothyroidism were normalized in consequence of hormone replacement and a negative correlation between their serum levels and TSH concentration was demonstrated in most subjects. However, in some patients a discrepancy in the response to levothyroxine between the pituitary and other target organs could be revealed. Additional evidence was disclosed that the pituitary thyrotroph sensitizes a minor decrease in serum thyroxine level, which would not be recognized by other target organs. Furthermore, it was revealed that during L-T4 replacement therapy in a large fraction of patients with subnormal serum TSH concentration blood levels of the measured markers often exceeded the upper limit of the normal range indicating the possibility of "tissue"-thyrotoxicosis beside the pituitary in other target organs, too. According to the present study which takes into consideration markers reflecting end-organ responsiveness to thyroid hormones it is recommended to adjust the dose of levothyroxine to maintain serum TSH in the normal range. For patients with subnormal TSH concentration a close follow-up is obligatory and in case od concomitantly raised free-thyroxine level the reduction of the levothyroxine dosage is proposed.

Adult↗

[Biological markers reflecting peripheral effects of thyroid hormones in autonomous thyroid adenoma].

In some patients with functioning thyroid autonomous nodules preclinical hyperthyroidism is detected. It is important to know, whether in this intermediate clinical state beside the suppression of pituitary TSH secretion other target organs are also affected by serum free-thyroxine and free-triiodothyronine levels still within the normal range. Determining some sensitive, but not specific biologic markers reflecting the impact of thyroid hormones at the peripheral tissue level, it was demonstrated that in the group of preclinical hyperthyroidism the mean level of plasma fibronectin exceeded that of the controls (mean +/- S. D.: 583.5 +/- 163.9 vs. 424.2 +/- 84.1 micrograms/ml, p less than 0.001), serum procollagen-III-peptide concentration was already significantly raised, though its value was still within the normal range (mean +/- S. D.: 0.73 +/- 0.17 vs. 0.57 +/- 0.16 U/ml, p less than 0.05), conversely, mean sex-hormone binding globulin level was the same as in euthyroid controls (mean +/- S. D. 47.4 +/- 18.2 vs. 48.3 +/- 16.3 nmol/l). The value of all three parameters was significantly elevated in patients with toxic nodular goiter. Based on the results of this study "tissue"-thyrotoxicosis is suspected in some patients with preclinical hyperthyroidism, which may have therapeutical implications.

Adult↗

[Decreased serum osteocalcin level in non-alcoholic and alcoholic chronic liver diseases].

Serum level of osteocalcin (OC) is believed to be a specific biochemical parameter of bone formation. Decreased serum OC has been reported in alcohol-intoxicated subjects, in patients with primary biliary cirrhosis and in patients with chronic alcoholic liver disease. The question was, whether lower OC level could be detected in patients with nonalcoholic and non-cholestatic chronic liver disease. The serum OC was measured by RIA developed in our laboratory. Results were compared to age and sex matched controls. Decreased OC level was found in 35 out of 47 (74%) patients with non-alcoholic and non-cholestatic liver disease as chronic persistent hepatitis, chronic active hepatitis, fatty liver and cirrhosis, in 21 out of 26 (80%) patients with alcoholic liver disease and in 8 out of 15 (53%) primary biliary cirrhosis. None of the patients had elevated value. There was no correlation between the decreased OC level and the duration or severity of the liver disease and the laboratory parameters as bilirubin, AST, ALT, alkaline phosphatase, albumin, prothrombin, and serum 25-OH-D3 vitamin level. Decreased OC was found also in the patients without cirrhosis. The possible causes are discussed. Relying upon these findings it is supposed that chronic liver disease by itself can influence the osteoblast activity also by some unknown mechanism.

Bone Diseases, Metabolic↗

Serum bone Gla protein in streak gonad syndrome.

Osteoporosis is one of the most common complications of streak gonad syndrome (SGS), however its pathogenesis is still unclear. Bone Gla protein (BGP) has been found to be a serum marker of bone turnover in various metabolic disease states. In the present study serum BGP and alkaline phosphatase (AP) were measured in 13 osteoporotic patients with SGS and in 56 healthy women. Mean (+/- SD) serum BGP levels were normal (7.5 +/- 2.0 ng/ml) in seven patients who had been on estrogen-progestin replacement therapy and became significantly elevated (P less than 0.001) 2 and 3 months after discontinuation of the treatment (15.3 +/- 2.3 and 13.2 +/- 1.0 ng/ml, respectively). Mean (+/- SD) serum AP (207 +/- 65 U/l) showed significant increases (P less than 0.05) 2 months after withdrawal of hormonal substitution (287 +/- 74 U/l). Mean (+/- SD) serum BGP (15.4 +/- 3.5) and AP (287 +/- 49) levels were significantly higher (P less than 0.001 and less than 0.05, respectively) in six patients with SGS who had not been on hormonal substitution. These findings are consistent with those obtained in postmenopausal women suffering from "high remodelling osteoporosis" and suggest that bone turnover in osteoporotic patients with SGS is increased and the skeletal loss is a consequence of accelerated bone loss rather than decreased bone formation.

Adult↗

Biologic blood markers reflecting thyroid hormone effect at peripheral tissue level in patients receiving levothyroxine replacement for hypothyroidism.

Plasma fibronectin, serum procollagen-III-peptide and sex-hormone-binding globulin as non-specific markers of thyroid hormone effect at peripheral tissue level were determined and their values were related with serum levels of TSH, free-thyroxine and triiodothyronine during levothyroxine sodium replacement therapy for hypothyroidism. Low levels of biologic markers characteristic of hypothyroidism were normalized in consequence of hormone replacement and a negative correlation between their serum levels, and TSH concentration was demonstrated in most subjects. However, in some patients a discrepancy in the response to levothyroxine between the pituitary and other target organs was revealed. Additional evidence was disclosed that the pituitary thyrotroph sensitizes a minor decrease in serum thyroxine level, which would not be recognized by other target organs. Furthermore, it was revealed that during L-T4 replacement therapy in a large fraction of patients with subnormal serum TSH concentration blood levels of the measured markers often exceeded the upper limit of the normal range indicating a possibility of "tissue" thyrotoxicosis, besides the pituitary, in other target organs, too. According to the present study, which takes into consideration markers reflecting end-organ responsiveness to thyroid hormones, it is recommended to adjust the dose of levothyroxine to maintain serum TSH in the normal range. For patients with subnormal TSH concentration a close follow-up is obligatory and in case of concomitantly raised free-thyroxine level the reduction of the levothyroxine dosage is proposed.

Adult↗

[Serum sex hormone-binding globulin levels in thyroid diseases].

Synthesis of "sex-hormone binding globulin" is influenced by the thyroid hormones and its concentration in the serum may be a marker of the thyroid hormone effect at the peripheral tissue (liver) level. Compared to euthyroid controls serum "sex-hormone binding globulin" concentration is elevated in overt hyperthyroidism (141.6 +/- 37.6 vs 48.3 +/- 16.2 nmol/l; p less than 0.001), conversely, its mean level is decreased in the hypothyroid group of patients (24.9 +/- 14.8 vs 48.3 +/- 16.2; p less than 0.001). In the group of subclinical hyperthyroidism the mean value of "sex-hormone binding globulin" corresponds to that in control subjects (47.4 +/- 16.8), while its serum level is near the lower border of the normal range in subclinical hypothyroidism (33.6 +/- 6.1 vs 48.3 +/- 16.2; p less than 0.01). During thyroid hormone replacement for hypothyroidism measurement of serum "sex-hormone binding globulin" may help to assess the response of the target organs to the hormone therapy. In patients with peripheral thyroid hormone resistance serum "sex-hormone binding globulin" level is within the normal range (51.3 +/- 9.8), its determination supports the diagnosis of this disease.

Adult↗

[Serum osteocalcin levels in healthy males and females in relation to age].

The measurement of serum osteocalcin is a new sensitive and specific method in the evaluation of calcium metabolism disorders. We established the normal values of healthy adult Hungarian women (n = 111, age: 20-86 yrs, mean: 47 yrs) and men (n = 70, age: 20-88 yrs, mean: 42 yrs) by radioimmunoassay method developed at our institute. Serum osteocalcin levels are constant between 20-50 yrs (7,8 +/- 2,4 ng/ml) while the values are significantly higher after 50 yrs of age (11,0 +/- 4,6 ng/ml) and remain constant afterwards. A correlation might be supposed between this elevation around 50 and bone loss around menopause. Serum osteocalcin values of men are constant with aging (11,0 +/- 3,9 ng/ml).

Age Factors↗

The measurement of the serum sex-hormone binding globulin in various thyroid diseases.

Synthesis of "sex-hormone binding globulin" (SHBG) is influenced by thyroid hormones and its concentration in the serum of female subjects may be a marker of thyroid hormone effect at the peripheral tissue (liver) level. Compared to the levels found in euthyroid females (n = 46), the mean (+/- S.D.) serum SHBG concentration was found elevated in overt hyperthyroidism (Graves' disease: n = 56; 141.6 +/- 37.6 vs. 48.3 +/- 16.2; toxic nodular goiter: n = 16; 119.9 +/- 50.7 vs. 48.3 +/- 16.2 nmol/l; P less than 0.001). In contrast, it was decreased in manifest hypothyroidism (n = 25; 24.9 +/- 14.8 vs. 48.3 +/- 16.2; P less than 0.001). In the group of preclinical hyperthyroidism (n = 43), despite suppressed TSH secretion, the serum value of SHBG was normal (47.4 +/- 16.8), while its serum level approached the lower border of the normal range in subclinical hypothyroidism (n = 10; 33.6 +/- 6.1 vs 48.3 +/- 16.2 nmol/l; P less than 0.01). Data indicate that the pituitary responds more sensitively than the liver to a slight change of the serum thyroid hormone level. During thyroid hormone replacement for hypothyroidism, measurement of serum SHBG may provide help to assess the response of the target organ to the given therapy. In patients with generalized resistance to thyroid hormone, the serum SHBG level is within the normal range (51.3 +/- 9.8 nmol/l), thus, its determination supports the diagnosis of this disease.

Biomarkers↗

[Thyroid function in severe non-thyroidal diseases].

The aim of the present study was to find out whether a change in the function of the pituitary-thyroid axis can be revealed in a relatively homogenous group of hematological patients. To clarify this problem serum levels of total-thyroxine and triidothyronine, free-thyroxine and free-triiodothyronine, reverse-triidothyronine and thyrotropin were detected in these patients. The majority of subjects with chronic myelogenous leukemia (in the remission phase) have normal pituitary-thyroid function, however a change in the peripheral metabolism of thyroxine can be revealed. Longitudinal studies in patients with acute myelogenous leukemia indicate that in some cases with the progression of the disease serum TSH and thyroid hormone levels decrease referring to secondary hypothyroidism and in these cases the measurement of serum free-thyroxine content by an analogue tracer method is not recommended. On the basis of the investigational results it is stated that in hematological patients the pituitary-thyroid function is influenced by the phase of illness and by the results of the given treatment.

Humans↗

Androgens and bone mineral content in patients with subtotal thyroidectomy for benign nodular disease.

To investigate the influence of thyroid surgery on the skeleton and different hormones a well characterized patient group of 24 women was selected who had undergone subtotal thyroidectomy for euthyroid benign nodular disease and remained euthyroid after the operation. Bone mineral content was determined in lumbar vertebrae, femoral neck and radius by dual and single photon absorptiometry. The serum levels of calcitonin, dehydroepiandrosterone, dehydroepiandrosterone-sulphate, androstenedione, total testosterone, cortisol and 25-hydroxyvitamin D were measured. A control group was created of 48 healthy female subjects. No reduction in bone mass was observed at the measured sites compared to appropriate controls. Beside normal bone mineral content significantly elevated serum levels of dehydroepiandrosterone (27.4 +/- 10.4 vs. 20.8 +/- 6.9 nmol/l) and androstenedione 9.3 +/- 3.3 vs. 6.6 +/- 2.2 nmol/l) were found without any clinical sign of androgen excess. There was no correlation between bone mineral content and these androgen levels. The serum calcitonin levels of all patients were low. With regard to the previously reported interactions among androgen, calcitonin and bone metabolism, our results raise the possibility of a relationship between higher androgen levels and preserved bone mass in these patients, while normal bone mineral content and calcitonin deficiency in these patients does not inevitably indicate that calcitonin does not affect bone tissue in adults.

Adenoma↗

Thyroid function in severe "nonthyroidal illness". Longitudinal studies in haematological patients.

It is known that in severe nonthyroidal illness the regulation of thyroid function, the distribution and metabolism of thyroid hormones may change. The present study aimed at clarifying whether a change in the function of the pituitary-thyroid axis can be detected in an approximately homogeneous group of haematological patients, and how it is correlated with the various phases of the disease and with the therapeutic result. Studies were performed on patients with chronic and acute myelogenous leukaemia: serum levels of total thyroxine and triiodothyronine, free thyroxine and triiodothyronine, reverse triiodothyronine and thyrotropic hormone were determined. Apart from a few cases, there was no dysfunction of the pituitary-thyroid axis in chronic leukaemic patients being in the remission phase. However, the peripheral thyroxine metabolism may be altered. The longitudinal studies on acute myelogenous leukaemic patients indicate that, with the progression of the disease, serum TSH and thyroid hormone levels were reduced in a part of the cases and it is not justified to assess the free serum thyroxine level by an analogue-tracer method in this disease. The examinations have revealed that the various phases of the clinical picture as well as the therapeutic results considerably influence the function of the pituitary-thyroid axis. It seems reasonable to consider these findings in the other severe nonthyroidal illnesses as well.

Adult↗