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J Podoba

Publications and source records attributed to J Podoba.

At least 19 recordsLinked to original sources

Thyroid hormone receptors and type I iodothyronine 5'-deiodinase activity of human thyroid toxic adenomas and benign cold nodules.

The majority of thyroid adenomas are of clonal origin. In a subset of toxic adenomas (TAs) and cold nodules (CNs) activating mutations in the thyrotropin (TSH) receptor or G s -alpha gene may explain the altered functions in these benign tumours. The present study was undertaken to investigate the status of functional thyroid hormone receptors, major thyroid hormone signal mediators, in both the human TAs and CNs in comparison with a normal thyroid tissue from the same patient. Electrophoretic mobility shift assays using a DR4 ("direct repeats" 4), a thyroid hormone responsive element (TRE) of human type I iodothyronine 5'-deiodinase demonstrated the DNA-binding of thyroid hormone receptors (TRs) in thyroid tissue nuclear extracts. A significant increase (p < 0.05) in the functional binding properties of TRs to the DR4 thyroid hormone responsive element was found in TAs when compared to normal thyroid tissue. Contrary, a marked diminution in the TR-TRE complex formation was found in CNs in comparison with normal thyroid tissue. In addition, functional activity of the iodothyronine 5'-deiodinase (5'DI) was analyzed in benign tumours, thyroid TAs and CNs in comparison with that of normal thyroid tissue. A significantly increased (p < 0.01) activity of 5'DI was demonstrated in TAs, and in contrast, decreased values of the enzyme activity were found in CNs when compared to a normal tissue. From the data it is suggested that both the status of TR-TRE complex formation and the activity of the 5'DI may be altered in benign tumours of human thyroid gland.

Adenoma↗

Iodized oil as a complement to iodized salt in schoolchildren in endemic goiter in Romania.

OBJECTIVE: To evaluate the long-term efficacy and possible side effects of low doses of iodized oil on iodine nutrition and thyroid function in endemic goiter in Romania. METHODS: Random selection of 214 schoolchildren aged 6-14 years. Serial measurements of urinary iodine, thyroid volume with ultrasound, serum concentrations of thyrotropin, free thyroxine, thyroglobulin and thyroid autoantibodies before and up to 2 years after the oral administration of 200 mg iodine in iodized oil. RESULTS: Urinary iodine concentrations indicated a moderate iodine deficiency before therapy, sharply increased soon after therapy and slowly decreased thereafter but remained within the normal range up to more than 1 year after therapy. The prevalence of goiter was 29% before the administration of iodized oil and 9% 1 year later. Thyroid function tests and autoantibodies were normal before and up to 2 years after therapy. CONCLUSION: A single dose of 200 mg iodine from oral Lipiodol appears adequate and safe for correcting moderate iodine deficiency in children.

Adolescent↗

Toward a consensus on reference values for thyroid volume in iodine-replete schoolchildren: results of a workshop on inter-observer and inter-equipment variation in sonographic measurement of thyroid volume.

OBJECTIVE: Interpretation of thyroid ultrasonography for assessing goiter prevalence requires valid reference criteria from iodine-sufficient populations. Reports have suggested the current reference criteria for thyroid volume (T(vol)) of WHO/ICCIDD (International Council for the Control of Iodine Deficiency Disorders) may be too high. Our objective was to determine if inter-observer and/or inter-equipment variability contributes to the disagreement in sonographic T(vol) in children reported from iodine-sufficient areas. DESIGN: A 2-day workshop in which four experienced ultrasound examiners from around Europe measured T(vol) in 45 6--12-year-old Swiss schoolchildren using four different portable ultrasound machines. One of the participating examiners (observer A) had generated the T(vol) data in European children that are the basis for the WHO/ICCIDD reference criteria. METHODS: Sonographic T(vol) was measured in each child by all four examiners on all four machines. Six hundred and eighty-four examinations were completed, with examiners having no knowledge of one another's results. Inter-observer and inter-equipment variation was calculated. RESULTS: Mean inter-equipment variation in T(vol) was 15.2% (95% CI: 14.1, 16.3%). There were no significant differences in T(vol) between equipment (P=0.51). For all observers, the mean inter-observer variation in T(vol) was 25.6% (95% CI: 23.9, 27.2%). At all ages and all body surface areas, there was a large systematic measurement bias (+30% volume) between the mean T(vol) of observer A and the mean Tvol of observers B, C and D. Reanalysis using data from observers B, C and D reduced the mean inter-observer variation in T(vol) to 13.3% (95% CI: 11.9, 14.7%). A correction factor for the systematic difference of operator A for the P50 and P97 of T(vol) was estimated using analysis of covariance. When applied to the WHO/ICCIDD reference data, it sharply reduced the discrepancy between the WHO/ICCIDD criteria and those from other iodine-sufficient children around the world. CONCLUSIONS: Inter-equipment error contributes minimally to reported differences in sonographic T(vol). Even among experienced examiners, inter-observer variation in sonographic T(vol) in children can be high, and probably contributes to the current disagreement on normative values in iodine-sufficient children. A systematic bias at least partially explains why the WHO/ICCIDD reference data differ from those reported from other iodine-sufficient children around the world. The findings argue strongly for the standardization of methods used for sonographic measurement of T(vol) in children.

Child↗

A programme of iodine supplementation using only iodised household salt is efficient--the case of Poland.

BACKGROUND: Iodine prophylaxis in Poland started in 1935 and has been interrupted twice: by World War II and in 1980 for economic reasons. Epidemiological surveys carried out after the Chernobyl accident in 1989 as well as in 1992/1993 and in 1994 as a 'ThyroMobil' study, revealed increased prevalence of goitre in children and adults. Ninety per cent of Poland was classified as an area of moderate iodine deficiency, and 10%, in the seaside area, as mild iodine deficiency territory. Iodine prophylaxis based on iodisation of household salt was introduced again in 1986 as a voluntary model and in 1997 as a mandatory model with 30+/-10 mg KI/kg salt. OBJECTIVE: The evaluation of the obligatory model of iodine prophylaxis in schoolchildren from the same schools in 1994 and 1999. METHODS: Thyroid volume was determined by ultrasonography. Ioduria in casual morning urine samples was measured using Sandell-Kolthoff's method, within the framework of the ThyroMobil study. RESULTS: Goitre prevalence decreased from 38.4 to 7% and urinary iodine concentration increased from 60.4 to 96.2 microg/l mean values between 1994 and 1999. In four schools the prevalence of goitre diminished below 5%. In 1999, 70% of children excreted over 60 microg I/l, and 36% over 100 microg I/l, whereas in 1994 the values were 44 and 13% respectively. CONCLUSION: The present findings indicate that iodine prophylaxis based only on iodised household salt is highly effective.

Adolescent↗

A survey of iodine intake and thyroid volume in Dutch schoolchildren: reference values in an iodine-sufficient area and the effect of puberty.

BACKGROUND: Iodine deficiency and endemic goiter have been reported in the past in The Netherlands, especially in the southeast. OBJECTIVE: To evaluate iodine intake and thyroid size in Dutch schoolchildren, contrasting those living in a formerly iodine-deficient region in the east (Doetinchem) with those living in an iodine-sufficient region in the west (Amsterdam area). DESIGN: Cross-sectional survey of 937 Dutch schoolchildren aged 6--18 years, of whom 390 lived in the eastern and 547 in the western part of the country. METHODS: Thyroid size was assessed by inspection and palpation as well as by ultrasound. Iodine intake was evaluated by questionnaires on dietary habits and by measurement of urinary iodine concentration. RESULTS: Eastern and western regions were similar with respect to median urinary iodine concentration (15.7 and 15.3 microg/dl, NS, Mann-Whitney U test), goiter prevalence by inspection and palpation (0.8 and 2.6%, P=0.08, chi-squared test), and thyroid volumes. The P97.5 values of thyroid volumes per age and body surface area group were all lower than the corresponding sex-specific normative WHO reference values. Iodized salt was not used by 45.7% of households. Daily bread consumption was five slices by boys and four slices by girls. Weekly milk consumption was 3 liters by boys and 2 liters by girls. Seafish was consumed once monthly. From these figures we calculated a mean daily iodine intake of 171 microg in boys and 143 microg in girls, in good agreement with the measured median urinary concentration of 16.7 microg/dl in boys and 14.5 microg/dl in girls. The sex difference in iodine excretion is fully accounted for by an extra daily consumption of one slice of bread (20 microg I) and one-seventh of a liter of milk (8.3 microg I) by boys. Thyroid volume increases with age, but a steep increase by 41% was observed in girls between 11 and 12 years, and by 55% in boys between 13 and 14 years, coinciding with peak height velocity. Girls have a larger thyroid volume at the ages of 12 and 13 years, but thyroid volume is larger in boys as of the age of 14 years. CONCLUSIONS: (1) Iodine deficiency disorders no longer exist in The Netherlands. (2) Bread consumption remains the main source of dietary iodine in The Netherlands; the contribution of iodized table salt and seafish is limited. (3) The earlier onset of puberty in girls renders their thyroid volume larger than in boys at the age of 12--13 years, but boys have a larger thyroid volume as of the age of 14 years.

Adolescent↗

Thyroid volumes and urinary iodine in Swiss school children, 17 years after improved prophylaxis of iodine deficiency.

Salt iodine content in Switzerland was raised from 7.5 to 15 mg per kg in 1980, and since then dietary iodine intake has been considered to be sufficient, even though a slight decrease due to imported food has recently been reported. The aim of this study was to establish normal values for thyroid volumes of school children who can be assumed to have had a sufficient iodine intake all their lifetime. Moreover. the present investigation was undertaken to verify that iodine sufficiency had been achieved equally in two regions each served by one of the two Swiss salt producers. Mean iodine concentration in urine spot samples from school children was 16.1 microg/dl, and it was identical in both the city of Lausanne (n=215) and the city of Solothurn (n=208). Thus it can be stated that in both cities (served by two different salt producers) iodine intake is equal and sufficient. Accordingly, thyroid volumes measured by ultrasound in school children aged 6 to 16 years were the same in both Lausanne (n=202) and Solothurn (n=207). Moreover, the age-adjusted median volumes at the 97th percentiles closely agree with and validate provisional international reference values recently proposed by the World Health Organisation and by the International Council for Control of Iodine Deficiency Disease.

Adolescent↗

In old age the majority of thyroid peroxidase autoantibodies are directed to a single TPO domain irrespective of thyroid function and iodine intake.

OBJECTIVE: We have examined (1) which epitopes on thyroid peroxidase (TPO) are recognized by TPO autoantibodies (TPO-Aab) in old age and to what extent? (2) Does the TPO-Aab pattern differ in euthyroid and hypothyroid elderly subjects or does it depend on their iodine intake? DESIGN: TPO-Aab positive sera obtained from a screening study of nursing-home residents living in areas of varying iodine intake were tested by competition studies with monoclonal antibodies (mAbs) recognizing different epitopes on TPO. SUBJECTS: The nursing-home residents with TPO-Aab positivity were from (A) an iodine abundant area (Eastern Hungary, median iodine excretion -MIE-: 0.462 mumol/mmol creatinine, N = 13); (B) an area of obligatory iodinated salt prophylaxis since the 1950s (Slovakia, MIE: 0.090 mumol/mmol creatinine, N = 11); (C) a moderately iodine-deficient area (Northern Hungary, MIE: 0.065 mumol/mmol creatinine, N = 13). MEASUREMENTS: Thirteen murine TPO antibodies generated against several epitopes of the four (A, B, C, D) antigenic domains on the TPO were co-incubated with the TPO-Aab positive sera on TPO coated microtitre plates. The amount of mAb bound was estimated after further incubation with goat anti-mouse antibodies, conjugated with horseradish peroxidase and tetramethylbenzidine as chromogen. The TPO-Aab positive sera were characterized by the pattern of percentage of inhibition of mAb binding caused by the TPO-Aabs. RESULTS: TPO-Aabs inhibited only the binding of mAbs raised against the antigenic domains A (mAb9, mAb2, mAb60) and B (mAb64, mAb59, mAb18, mAb15). The extent of inhibition depended upon the TPO-Aab titre but in all cases the binding of mAb9 was inhibited to the highest degree. The percentage inhibition of mAb9 was (a) 34 +/- 17% (M +/- SD) caused by sera (N = 8) with TPO-Aab titre 1/100-1/200 (higher than that of all mAbs recognizing domain B, P < 0.01-P < 0.001), (b) 76 +/- 18% caused by sera (N = 14) with TPO-Aab titre 1/1000 (higher than that of all other mAbs -P < 0.01-P < 0.001, except mAb64), (c) 99 +/- 4% caused by sera (N = 15) with TPO-Aab titre 1/4000-1/16,000 (higher than that of all other mAbs, P < 0.01-P < 0.001). Thus, only mAb9 was inhibited completely by high titres of TPO-Aabs. The qualitative and quantitative distribution pattern of mAb inhibition was similar in the subgroups of elderly hypothyroid and euthyroid subjects with comparable TPO-Aab levels, as well as in the subgroups with varying iodine intake. CONCLUSIONS: (1) In old age, there is a polyclonal TPO autoantibody response but the majority of the autoantibodies are directed to the TPO region mapped by or close to mAb9 (domain A); (2) the autoantibody response does not differ in elderly subjects with or without the clinical manifestations of autoimmune thyroid disease and does not depend on the iodine supply of the elderly subjects.

Aged↗

Comparative screening for thyroid disorders in old age in areas of iodine deficiency, long-term iodine prophylaxis and abundant iodine intake.

OBJECTIVE: To investigate the effect of varying amounts of iodine intake on the prevalence of thyroid dysfunction, autoimmunity and goitre in old age. DESIGN: The first screening study where elderly subjects with varying amounts of iodine supply but from the same geographical and ethnographical region (Carpathian basin) were compared, and all hormone measurements and ultrasonography were performed by the same laboratory or person. PATIENTS: Nursing home residents were screened for thyroid disorders from: (A) an iodine-deficient area, Northern Hungary (n = 119; median age 81 years; median iodine excretion (MIE) 0.065 mumol/mmol creatinine (equivalent to 72 micrograms/g creatinine); (B) an area of obligatory iodinated salt prophylaxis since the 1950s, Slovakia (n = 135; median age 81 years, MIE 0.090 mumol/mmol creatinine (equivalent to 100 micrograms/g creatinine)) and (C) an abundant iodine intake area, Eastern Hungary (n = 92; median age 78 years; MIE 0.462 mumol/mmol creatinine (equivalent to 513 micrograms/g creatinine)). MEASUREMENTS: TSH, T4, free T4, T3, thyroglobulin (Tg), antibodies to Tg (AbTg) and to thyroid peroxidase (AbTPO), iodine excretion, ultrasonography of the thyroid gland. RESULTS: In regions A, B, and C, the prevalence of unsuspected clinical hypothyroidism was 0.8%, 1.5% and 7.6% (P = 0.006), with all cases except one being antibody positive (Ab+). The occurrence of subclinical hypothyroidism was 4.2% in region A, 10.4% in region B and 23.9% in region C (P < 0.001), but only 3 of 22 cases with subclinical hypothyroidism from region C were Ab+. The overall prevalence of Ab positivity (either antiTg+ or antiTPO+) was similar in the three regions (A, 19.3%; B, 24.4%; C, 22.8%). The occurrence of hyperthyroidism (clinical plus subclinical) was 3.4% in region A, 3.0% in region B and 0% in region C (not significant). The rate of elevated Tg levels was similar in the three regions. The prevalence of goitre was 39.4%, 16.4% and 12.2% (P < 0.001), respectively in regions A, B and C. In euthyroid subjects the mean ultrasonographically determined thyroid volume was 21.9 ml in region A, 13.6 ml in region B and 15.1 ml in region C (ANOVA F = 5.76; P = 0.0038). There was no significant difference in the occurrence of cases with hypoechogenic echotexture of the thyroid gland. CONCLUSIONS: The screening for hypothyroidism in nursing home residents living in iodine-rich regions is justified by the high prevalence of unsuspected clinical hypothyroidism. The high prevalence of antibody positivity in old age is independent of the iodine supply, but iodine supply has a determining role in the development of autoimmune hypothyroidism in the aged. Most cases of subclinical hypothyroidism in iodine-rich regions are not of autoimmune origin. In old age, hypoechogenic texture of the thyroid gland is not predictive of thyroid dysfunction.

Aged↗

Thyroid volume and urinary iodine in European schoolchildren: standardization of values for assessment of iodine deficiency.

Up to 1992, most European countries used to be moderately to severely iodine deficient. The present study aimed at evaluating possible changes in the status of iodine nutrition in 12 European countries during the past few years. Thyroid volume was measured by ultrasonography in 7599 schoolchildren aged 7-15 years in one to fifteen sites in The Netherlands. Belgium, Luxemburg, France, Germany, Austria, Italy, Poland, the Czech and Slovak Republics, Hungary and Romania. The concentrations of urinary iodine were measured in 5709 of them. A mobile unit (ThyroMobil van) equipped with a sonographic device and facilities for the collection of urine samples visited all sites in the 12 countries. All ultrasounds and all urinary iodine assays were performed by the same investigators. The status of iodine nutrition in schoolchildren has markedly improved in many European countries and is presently normal in The Netherlands, France and Slovakia. It remains unchanged in other countries such as Belgium. There is an inverse relationship between urinary iodine and thyroid volume in schoolchildren in Europe. Goiter occurs as soon as the urinary iodine is below a critical threshold of 10 micrograms/dl. Its prevalence is up to 10 to 40% in some remote European areas. This work produced updated recommendations for the normal volume of the thyroid measured by ultrasonography as a function of age, sex and body surface area in iodine-replete schoolchildren in Europe. This study proposes a method for a standardized evaluation of iodine nutrition on a continental basis, which could be used in other continents.

Adolescent↗

[Fibrillary glomerulopathy].

The authors present an account on contemporary knowledge of the diagnosis and differential diagnosis of fibrillar glomerulopathies. The latter are characterized by extracellular localized microfibrils and microtubules resp. in the glomeruli of the kidneys, their diameter being 8-60 nm. They are divided into amyloid and non-amyloid types. The others are classified according to the immunofluorescent finding into immunoglobulin positive and negative ones. The differential diagnosis is important in particular in immunoglobulin positive ones as they are present in serious diseases such as cryoglobulinaemia, monoclonal gammapathy, systemic lupus erythematosus and immunotactoid glomerulopathy.

Adult↗

[Octreotide in the treatment of thyrotropin-secreting pituitary adenomas].

The authors detected in a 30-year-old patient a very rare type of hyperthyroidism caused by a thyrotropin secreting pituitary adenoma. Scintigraphic examination of the pituitary by means of 111In radiolabelled octreotide revealed an increased accumulation of the radiopharmaceutical preparation in the tumour, which confirmed the high density of somatostatin receptors. After onset of octreotide treatment (Sandostatin, Sandoz, Switzerland) 3 x 100 ug/day by the s.c. route a brisk decline and normalization of thyrotropin already after the first dose was recorded. The thyroxine concentration declined slowly to the upper range of normal values. After 5 months treatment despite the positive response to receptor scintigraphy diminution of the adenoma was not recorded. Again an increase of thyrotropin above the upper limit of the reference range and a marked rise of thyroxinaemia were observed. Six months after radical selective trans-sphenoidal adenomectomy normal pituitary function was confirmed.

Adenoma↗

[Thyrotropin-secreting adenomas of the hypophysis].

Thyrotropin secreting pituitary adenomas are scarce. They may cause an extremely rare form of hyperthyroidism. The diagnosis is often delayed because the clinical symptoms are attributed to common types of hyperthyroidism. The diagnosis involves detection of elevated or normal (unsuppressed) thyrotropin levels in hyperthyroid patients and evidence of a pituitary adenoma by computed tomography or magnetic resonance imaging. The thyrotropin response in the thyrotropin-releasing hormone test is either absent or insufficient. When the pituitary microadenoma appears to be undetectable, the familiar syndrome of selective pituitary resistance to thyroid hormones has to be excluded. Treatment involves extirpation of the tumour. If the macroadenoma is not removed completely, external radiotherapy of the pituitary follows. If this conventional treatment does not produce an adequate effect, treatment with long-acting somatostatin analogues is recommended.

Adenoma↗

[Surgical treatment of hyperparathyroidism].

The authors present their experience with the diagnosis and treatment of hyperparathyroidism in a group of eight patients operated between June 1993 and November 1993 at the Surgical Clinic of Dérer's Hospital in Bratislava-Kramáre. They summarize the findings on the disease from the literature and compare them with their own clinical observations, which confirm the indication of surgical revision as a useful localizing method, and the necessity of perioperative histological diagnosis to determine the extent of surgery.

Adult↗

[Thin-needle aspiration biopsy in the preoperative diagnosis of non-toxic nodular goiter].

The ascertainment of diagnostic reliability of fine needle aspiration biopsy in preoperative examination of non-toxic goitres is performed by comparing its results with the findings of the definitive histologic examination. The set of patients did not include those with the cytological finding of Hürtle tumour for the impossibility to distinguish between adenomas and carcinomas from oxyphilic cells by means of cytologic examination. Aspirates were stained by May, Grunwald and Giemsa method. Histologic results were gained from 185 patients. Cytologic findings were considered as benign in 95 cases (however 3 cases of cancer were revealed by the histologist--false negativity). In 90 cases, atypia, findings of suspectivity, or diagnosis of malignity were described, however the histologist evaluated 49 cases of goitres as being benign (false positivity). Totally 44 cases of malignant tumours were histologically diagnosed. Diagnostic sensitivity in our set of patients was 0.97 and diagnostic specificity was 0.46. In accordance with the available literature, fine needle cytodiagnosis is considered to represent an appropriate screening method in the process of decision as to whether conservative or surgical therapy with histologic verification in patients with non-toxic nodular goitres is to be indicated. (Tab. 1, Ref. 6.).

Biopsy, Needle↗

[The effectiveness of iodine prophylaxis of endemic goiter in Slovakia from the viewpoint of physical and ultrasonographic examinations of the thyroid gland].

Being aimed at the effectivity of iodine prophylaxis of endemic goitre the authors examined 2946 children and adolescents at the age of 6-18 years during the period from 1989 to 1995 in 6 regions of Slovakia. The thyroid glands were examined physically and ultrasonographically. The authors have found out that the occurrence rate of diffuse goitre is acceptable and it is not meeting the criteria of endemic goitre. No case of nodular goitre was revealed. Similarly to the relative frequency of diffuse goitre, neither the ultrasonographically measured volumes of thyroid glands differed among various areas. They are comparable with the volumes detected in countries with a sufficient iodine supply. The use of criteria for iodine deficiency evaluation recommended by WHO (goitre occurrence, thyroid gland volume, ioduria) leads the authors to consider the current prophylaxis of endemic goitre as being effective and successful. (Tab. 5, Ref. 20.).

Adolescent↗

Thyroid volume and urinary iodine in school children and adolescents in Slovakia after 40 years of iodine prophylaxis.

The thyroid volume (by ultrasonographic volumetry) was estimated in 4,254 schoolchildren and adolescents 6-18 years of age from 12 districts of Slovakia and urinary iodine (by dry alkaline ashing followed by spectrophotometry) in 1,174 spot urine samples. No differences in thyroid volume or in iodine excretion between individual districts were found. Similarly, no differences in thyroid volume between sexes were found up to the age of 14 years, however, thereafter, such volumes were considerably higher in boys. When comparing our cummulated data with those reported by others for a population with optimal iodine intake, it was found: 1. the medians for most of the examined age groups were slightly higher, 2. the percentage of values which were higher than 97 percentiles of normal population was 3.01 for the age of 6-14 years, while that for the age of 15-18 years was 9.04. Only 35.9% of all values of urinary iodine were in the optimal range (i.e. 10-20 mud/dl), while 56.1 were less than 10 micrograms/dl and 15.9% less than 5 micrograms/dl, the remaining 8.0% over 20 micrograms/dl. In spite of long-term iodine prophylaxis (since 1949), the intake of iodine apparently is still not satisfactory, since a considerable amount of individuals appeared to be iodine deficient on the day of examination. Iodine intake, however, may be marginally sufficient up to the age of about 13-14 years, while later a higher number of enlarged thyroids was found which may be classified as goitre endemy grade I.

Adolescent↗