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H Bornet

Publications and source records attributed to H Bornet.

At least 37 records · Page 2Linked to original sources
PubMed1984

[Immunohistochemistry of thyroglobulin by indirect immunofluorescence in thyroid cancers].

The authors have developed an indirect immunofluorescence technique for histochemical detection of thyroglobulin and have tested it on 66 tissue sections. Fluorescence reflecting the presence of thyroglobulin was elicited in 57 samples of differentiated thyroid tissue, including healthy or hyperfunctional tissue and primary or metastatic papillary or follicular carcinomas. Thyroglobulin was found to be distributed heterogeneously between different areas and different cells. It may occupy the whole cell, the apex, the colloid substance and sometimes extracellular spaces. No fluorescence was present in non-thyroid tissues. This technique could be applied mainly to the diagnosis of thyroid carcinomas, where 25 metastases have been examined by this method, and to clear cell carcinomas. In these two cases, thyroglobulin appeared to be a good marker of tumoral tissue.

Female↗
PubMed1984

Metabolic alterations induced by chronic heat exposure in the rat: the involvement of thyroid function.

The effects of chronic exposure to high environmental temperature (34 degrees C) on T4 production rate, food-intake, growth-rate and resting metabolic rate were investigated in adult male rats. This study was designed to examine the extent of variations and possible relationships between these parameters. As compared to control rats of the same body weight kept at 25 degrees C, rats exposed to 34 degrees C for 3-4 weeks exhibited a retarded growth-rate: 2.3 vs 4.0 g/day, a reduced food-intake: 15.2 vs 23.2 g/day, a decreased T4 production-rate: 1.8 vs 2.7 micrograms/day and a decreased oxygen consumption: 4.0 vs 5.4 ml/min. Heat-exposure altered the 4 parameters to a similar extent. T4 supplementation (3 micrograms/day) which induced a decrease in plasma TSH concentration, did not restore a normal growth-rate in heat-exposed rats. The decreased food-intake of the heat-exposed rats was not associated with any significant changes in the daily pattern of variations of liver glycogen content, or in the mean daily levels of blood glucose or insulin. The ratio T3 to rT3 in plasma was not altered by chronic heat exposure. When rats which had been chronically exposed to heat (25 days at 34 degrees C) were exposed to 25 degrees C, growth-rate, food-intake and oxygen consumption rapidly increased to control values whereas the rate of T4 production remained low. It is concluded that (1) a decrease in thyroid hormone economy is not directly involved in the alterations of growth and energy expenditure in rats chronically exposed to heat, (2) heat exposure does not lead to the establishment of a fasted state resulting from a large reduction in voluntary food intake, (3) metabolic alterations induced by heat exposure are rapidly and completely reversible upon decreasing the environmental temperature.

Animals↗
PubMed1983

[Effect of estrogens on the value of serum thyroglobulin].

Serum thyroglobulin (TG) is considered as a useful index of differentiated thyroid carcinoma evolution. Previous studies have suggested that TG levels might be dependent upon oestrogens. Here TG levels were determined in volunteers , free of any thyroid disease, divided into 5 groups according to estrogen level. Results (mean +/- s.d.) indicated that Tg levels in men group A (n = 9): 6,6 +/- 2,8 ng/ml in women undergoing oestroprogestagen treatment group B (n = 10) 3,7 +/- 1,5 ng/ml; in women free of oestroprogestaten treatment group C (n = 10): 5,9 +/- 4,0 ng/ml; in pregnant women group D (n = 40): 4,6 +/- 2,7 ng/ml, and in parturient women group E (n = 4): 7,2 +/- 2,2 ng/ml; were not correlated to estrogen levels. However, in a group where thyroid gland was not carefully examined i.c. a "blood doners group", a difference (p less than 0,005) was found between women (29 +/- 15) and men (14 +/- 9). Sex and estrogen levels there fore do not influence the TG index which as a result can be used in the monitoring of thyroid carcinoma in pregnant women.

Adult↗
PubMed1981

Radioimmunoassay of serum thyroglobulin. Technique and clinical results.

A radioimmunoassay technique using a double antibody procedure for human serum thyroglobulin (HTg) is described. Only antigen labeling with iodine-125 is performed extemporaneously, the other reagents being purchased commercially. Quality criteria were: sensitivity (2 microgram/l), interassay reproducibility (coefficient of variance, C.V. = 11%) and specificity are comparable with those of previously published techniques. Normal limits for serum HTg concentrations were established on the basis of 65 assays (33.0 +/- 21.20 microgram/l). In 69 subjects exhibiting goiters and cold nodules, the values observed were considerably higher and more dispersed (81 +/- 57 microgram/l); the same observation was made for the the cases of Basedow's disease studied. Patients who had undergone thyroid ablation for thyroid cancer exhibited a low or nondemonstrable HTg concentration, except for seven subjects showing osseous and/or pulmonary functionally active metastases of a differentiated cancer whose HTg levels were significantly higher (300-400 microgram/l). These results concur with several previous reports in emphasizing the interest of assaying serum HTg during the surveillance of differentiated cancers of the thyroid.

Humans↗
PubMed1981

Human serum albumin labelled with 99Tcm and 131I for total blood volume determination: A critical and comparative analysis in vivo and in vitro.

The increased plasma volume or total blood volume determined with radioactive tracers often have no physical or pathologic explanation. The plasma volume and blood dilution were simultaneously measured in 5 patients who had received human serum albumin labelled with 99Tcm or 131I. In each case and for each tracer, a biexponential dilution curve was obtained. The measured plasma volume was consistently higher after 99Tcm-labelled albumin. The results are correlated with the presence of non-protein artifacts arising from the labelling process and proteinaceous compounds arising from denaturation.

Blood Volume Determination↗
PubMed1980

[Triiodothyronine radioimmunoassay. Comparison of the different factors between two technics (author's transl)].

Triiodothyronine concentration was determined in human serum and in thyroid extracts by two radioimmunoassay technics. Both antibodies, radioactive T3, stable T3, protein-binding-hormone inhibitors, methods used to separate the free from the bound fractions were different. Each factor from a method was substituted to the homologue of the other method. The results occasionally showed a variation of 32 p. cent in the first method and 50 p. cent in the second one. However the results gave a correct interpretation of the triiodothyronine values measured in human serum and in thyroid extracts.

Humans↗
PubMed1978

Thyroid function and blood pressure in two new strains of spontaneously hypertensive and normotensive rats.

1. The influence of thryoid function on the development of hypertension was studied in strains of spontaneously hypertensive (SH) and normotensive rats. 2. Surgical thyroidectomy decreased systolic blood pressure more markedly in SH rats than in normotensive rats. The effects of oral administration of 5 and 100 micrograms of thyroxine 24 h-1 100 g-1 were studied in the thyroidectomized animals. In the two strains the blood pressure returned to control levels only after administration of the larger dose. 3. The evolution of body weight, total plasma tri-iodothyronine (T3) and tetraiodothyronine (T4) concentrations were followed as a function of age in SH rats and normotensive rats from 5 to 21 weeks. At each age, SH rats showed significantly larger body weight and decreased T4 concentrations. Plasma T3 in SH rats was lower than in normotensive rats until 15 weeks of age, after which the difference was not significant. At 11 weeks, plasms free T3 and T4 concentrations were slightly lower in SH rats than in normotensive rats. 4. The more marked hypotensive effects of surgical thyroidectomy in SH rats cannot be related to increased thyroid function.

Aging↗
PubMed1978

[Study of thyroxine synthesis in non-toxic goiters using dispersed thyroid cells (author's transl)].

The ability of thyroid tissue from non-toxic goiter to synthesis thyroid hormones was investigated by measuring 131 I-iodide incorporation in T4 in dispersed thyroid cell system. Dispersed thyroid cells were prepared by trypsinization from 5 pathological and 2 Normal thyroid specimens. The patients with non-toxic goiter were euthyroid or in mild hypothyroidism. The capacity of T4 synthesis was decreased in 4 cases and increased in 1 as compared to that of normal thyroid tissue. In one case, the impairement of T4 synthesis seemed to be related to the presence of thyralbumin as the major thyroid iodoprotein. In the 3 other cases with a decreased T4 synthesis, a good correlation was found between the capacity of T4 synthesis in dispersed thyroid cells and the thyroid activity in vivo (6 hr - 132 I-uptake). The discrepancy between in vivo and in vitro data in the case showing an increased T4 synthesis could be explained by the difference in the iodide supply in vitro (5 X 10(-8) M) and in vivo (urinary iodide : 2 microgram/24 hr). Thyroid cell preparations may serve as an experimental model to confirm or invalidate the hypothesis of a defect of thyroid hormone synthesis in non-toxic goiters.

Cells, Cultured↗
PubMed1976

Thyroid iodine organification defects: a case with lack of thyroglobulin iodination and a case without any peroxidase activity.

Two patients (G2, G3) with iodine organification defect were studied. The first patient (G2), a 25-year-old women with no clinical hypothyroidism, had had her goiter for 10 years; 62% of the thyroidal iodine was released by perchlorate indicating iodine organification defect. The thyroid tissue obtained at thyroidectomy contained a normal concentration of thyroid peroxidase (I2 formation from I-) when tested after solubilization of the enzyme by trypsin and digitonin treatment of the particulate material. 1. The enzymatic activity (G2-TPO) behaved on DEAE cellulose chromatography very differently from those of hog (P-TPO) or another human goiter peroxidase (G1-TPO) (Pommier, et al., J Clin Endocrinol Metab 39: 69, 1974): the molarity of elution was 2M NaCl instead of 0.15 mM. 2. Both P-TPO and G2-TPO catalyzed iodide peroxidation (I- leads to I2) but the Km (iodide) value for G2-TPO was much lower (2.3 x 10(-2) M) when compared with that of P-TPO (3.7 x 10(-3) M) or G1-TPO (3.5 x 10(-3) M). In addition, the optimum pH for this reaction differed markedly (pH 6.1 instead of 7.9). 3. G2-TPO was poorly efficient in catalyzing the oxidation of gaiacol to tetragaiacol. 4. G2-TPO was unable to perform the iodination of non-iodinated goiter thyroglobulin whatever the pH and the iodide concentration. 5. Thyroglobulin from this goiter (G2) was almost not iodinated (0.0014%), i.e., 0.07 atoms iodine/mole thyroglobulin), and its total content in the gland was very low (0.3-4 g/1000 g wet tissue instead of 25 g). A clear discrepancy was thus shown between the euthyroid state of this patient and the total lack of iodinating activity of the isolated peroxidase. The second patient (G3), a 17-year-old man with clinical hypothyroidism, had had his goiter for 5 years. 100% of the thyroidal iodine was released by perchlorate indicating a complete iodine organification defect. The thyroid tissue obtained at thyroidectomy contained no peroxidase activity when tested before and after treatment of the particulate material by trypsin and digitonin and even in the presence of hematin. Thyroglobulin from this goiter, which was almost non-iodinated (0.0014%), was present in normal amounts in the gland (congruent to 25 g/1000 g).

Adolescent↗
PubMed1975

[Radioimmunoassay without extraction of L-triiodothyronine in human serum].

A radio-immunoassay of L-triiodothyronin is described. Blinding of T3 to TBG is prevented by salicylate (1%--w/v). The rabbit antiserum obtained by injection of a complexe T3-bovine serum albumin is diluted between 1/10000 and 1/20000. Bound and free hormone are separated by polyethylene glycol (17%--w/v). Serum T3-concentration in normal subjects averaged 132 +/- 29 ng/dl (SD). In hyperthyroid and hypothyroid patients, these values were respectively 351 +/- 118 ng/dl and 68 +/- 21 ng/dl.

Humans↗