Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “THYROID GLAND”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,081 records · Page 60Linked to original sources
PubMed1999

Ultrastructure of the thyroid gland of the one-humped camel (Camelus dromedarius).

Follicular epithelium of the thyroid gland of the one-humped camel was examined by light and electron microscopy. It consisted of a single type of epithelial cell which varied from flattened to columnar in shape. Follicular epithelial cells were characterized by the presence of markedly dilated cisternae of rough-surfaced endoplasmic reticulum, well developed Golgi apparatus, abundant small vesicles (150 nm to 200 nm in diameter) in the apical cytoplasm, and electron-dense colloid droplets measuring from 250 nm to 1600 nm. Follicular epithelial cells frequently showed apocrine secretion into colloidal lumens. Apocrine protrusions with smooth surface were dome-like or balloon-like structures and contained a fine granular matrix. These findings indicate that the morphological features of the follicular epithelial cells of the thyroid gland of the camel are essentially similar to those of mammals except for the presence of apocrine secretion, which is unique to the camel.

Animals↗
PubMed1987

Carbamazepine (Tegretol) inhibits in vivo iodide uptake and hormone synthesis in rat thyroid glands.

Decreased serum concentrations of T3 and T4 occur in patients treated with the anticonvulsant drug carbamazepine (CBZ), but with rare exception, these patients remain euthyroid. The mechanism that accounts for diminished hormone levels is unknown, and our objective was to study the direct effect of CBZ on iodide uptake and hormone synthesis in thyroid glands of CBZ-treated and pair-fed control rats. Chronic ingestion (per os) of CBZ in male rats reduced the four hour thyroid 131I-iodide uptake by approximately 60%. This inhibition occurred after the animals had received sufficient CBZ to attain plasma CBZ concentrations of 0.8 microgram/ml. Continued treatment with CBZ ranging from 560 to 800 mg/kg/day for 14 days did not result in further inhibition of iodide uptake even though the plasma CBZ concentrations had increased 6-20 fold. No inhibition of iodide uptake was apparent when the animals initially received CBZ ranging from 40 to 152 mg/kg body weight for 22 days when there were no detectable levels of plasma CBZ. Overall growth rates of CBZ-treated rats were slightly (6-10%) less than the pair-fed control animals. Plasma T4 concentrations were reduced by 18% (p less than 0.05) in the CBZ-fed animals, while T3 concentrations were diminished by 53% (p less than 0.01). CBZ appeared to alter thyroidal iodide transport because the thyroid:plasma iodide ratios were decreased by 26% in the drug-treated rats. The distribution of radioiodine in thyroidal iodoamino acids was essentially the same in both groups of rats but the absolute quantities of radioiodine were more than 2.5 times greater in the control rats. CBZ failed to inhibit peroxidase-catalyzed iodide and guaiacol oxidation in vitro. No differences in thyroid gland morphology were noted in the two groups of animals, but weights of the glands from the CBZ-fed animals increased by 25% after 42 days. It is concluded that CBZ, or its metabolites, has a direct inhibitory effect on iodide utilization and hormone synthesis by the thyroid gland.

Animals↗
PubMed1985

Gangliosides of human thyroid gland.

The ganglioside composition of adult human thyroid gland was examined in autopsy material obtained from patients who died of circulatory diseases but who showed no signs of thyroid disorders. The concentrations of phospholipids, cholesterol and gangliosides (lipid-bound sialic acid) in the whole glands were 5.2, 4.3 and 0.12 mmol/kg fresh tissue weight and, in dissected follicular material, 7.0, 3.4 and 0.24 mmol/kg tissue, respectively. The molar ratio of phospholipids/cholesterol/gangliosides in the follicular material was 1.00:0.49:0.034. Twelve molecular species of gangliosides were isolated and identified. Gangliosides GM3 and GD3 were most abundant, but GD1a, GD1b, GT1b and 3'-LM1 were also present in quantities greater than 5% of the total gangliosides. N-Acetylneuraminic acid and an alkali labile sialic acid, probably N-acetyl-9-O-acetylneuraminic acid, were found to occur in human thyroid.

Adult↗
PubMed1988

[Possibility of the neoplastic transformation of thyroid gland cells in the graft vs host reaction].

The experiments were carried out on 60 first generation hybrids. Acute systemic "graft-versus-host" reaction (GVHR) was induced in (CBA X C57B1/6) X 60 X 10(6) hybrids by intravenous administration of spleen cells from C57B1/6 parents. Thyroid glands were examined on the 3rd, 10th and 24th days of GVHR. Chronic GVHR was studied in accordance with routine model. (C57B1/6 X DBA/2) hybrids were given 50 X 10(6) spleen cells from DBA/2 parents. Thyroid glands were investigated 6 months after GVHR induction. On the 10th day of GVHR histological examination revealed that follicular-like adenoma tumours with pronounced cellular abnormalities tended to appear in thyroid gland. In a chronic form of GVHR the histological pattern corresponds to that of follicular cancer.

Adenoma↗
PubMedDate not supplied

[The concentration of nucleic acids in the subcellular structures of the thyroid gland in several of its diseases].

As a result of examination of whole tissue and subcellular structures of the human thyroid gland there was revealed an increase in the nucleic acid content in the whole tissue, nuclei and the RNA in the microsomal fractions--in toxic goiter, adenoma of the thyroid gland, and strumitis. The content of nucleic acids in the mitochondria increased only in strumitis. Nucleic acid level changed but little in the whole tissue and subcellular structures in nontoxic goiter.

Adenoma↗
PubMed2004

Metastasis of renal cell carcinoma to the thyroid gland 19 years after nephrectomy: a case report.

Although metastases to the thyroid are never uncommon at autopsy in patients who died of malignancy, metastatic thyroid carcinomas are rarely detected in clinical practice in most cases and cases of secondary thyroid cancer which require thyroid surgery clinically are few. A clinical case of thyroid metastasis from renal cell carcinoma with thyroidectomy is described herein. An 87-year-old Japanese woman was referred to us for a slow-growing palpable neck tumor with dysphagia. She had undergone a nephrectomy for renal clear cell carcinoma 19 years earlier at another hospital. Preoperative imaging examinations suspected an adenomatous goiter and a fine needle aspiration (FNA) cytology was suggestive of an atypical follicular tumor. Hemithyroidectomy was performed as a follicular tumor of thyroid for restriction of subjective symptom. A pathological examination of the thyroid tumor revealed clear cell carcinoma, postoperatively. The negative result of immunohistochemical staining for thyroglobulin also suggested metastatic renal cell carcinoma to the thyroid. Clinically significant metastases to the thyroid gland are relatively infrequent. However, if patient who bears a thyroid tumor has a history of malignancy, the possibility of metastatic disease should be taken under consideration.

Aged↗
PubMed1983

Effects of radiation on parafollicular C cells of the thyroid gland.

While radiation has well-recognized effects on follicular cells of the thyroid gland, those on parafollicular C cells are not yet established. Low-dose radiation that has been proved to be nonablative and carcinogenic to follicular cells was administered to 8-week-old Long-Evans rats to study the changes in C cell number and function. Circulating calcitonin levels were significantly reduced in animals that had undergone radiation at age 24 months. Mean calcitonin values were 0.66 (+/- 0.20) ng/ml and 1.64 (+/- 0.59) ng/ml for control males and females compared with 0.14 (+/- 0.06) ng/ml and 0.11 (+/- 0.01) ng/ml for males (P less than 0.05) and females (P less than 0.001) that had undergone radiation, respectively. These levels correlated well with C cell population density in thyroid glands in the control group and in the group that had undergone radiation as evidenced by light microscopy. Routine hematoxylin and eosin staining showed C cell hyperplasia in 77% of control animals of both sexes compared with 4% in animals that had undergone radiation (P less than 0.005). Immunoperoxidase staining with an anticalcitonin antibody showed virtual absence of C cells in most animals that had undergone radiation compared with diffusely scattered cells in animals in the control group. Medullary carcinomas occurred in 14% of animals in the control group compared with 3% of animals that had undergone radiation (P less than 0.05). These data indicate that the radiation dosage that is carcinogenic to the follicular epithelium causes lethal injury to C cells and thus suggest that C cells are more sensitive to radiation than are follicular cells. This increased sensitivity could explain the virtual absence of C cells, decrease in calcitonin levels, and reduced numbers of medullary carcinomas in the animals that had undergone radiation.

Animals↗
PubMed1977

Characterization of T3 immunoreactivity release from thyroid gland in vitro a reflection of colloid droplet formation.

T3 immunoreactivity release from the thyroid gland in vitro was shown to be increased by TSH. In the present study, we sought to determine whether the T3 immunoreactivity release is an indicator of thyroid hormone secretion or due to hormone synthesis. When thyroid glands from mice were incubated with TSH, T3 immunoreactivity release was increased in parallel with intracellular colloid droplet formation in a dose related manner. When colchicine, a known inhibitor of colloid droplet formation, was added, both T3 immunoreactivity release and colloid droplet formation were inhibited, whereas MMI, an inhibitor of hormone synthesis, failed to influence both aspects. Thus T3 immunoreactivity release as a reflection of colloid droplet formation was demonstrated. The analysis of the released immunoreactivity by Sephadex column and subsequent radioimmunoassay suggested that the T3 immunoreactivity was, to a considerable extent, due to macromolecule instead of T3 itself. The effect of I- or Li+ to inhibit thyroid hormone secretion was shown to be on the step prior to, but not subsequent to, colloid droplet formation.

Animals↗
PubMedDate not supplied

Intracytoplasmic lumina in medullary carcinoma of the thyroid gland. Report of a case with cytologic and immunocytochemical features.

BACKGROUND: Intracytoplasmic lumina (ICL) have been observed frequently in breast carcinoma cells. However, they are extremely rare in thyroid gland tumors. We encountered a medullary carcinoma of the thyroid (MCT) with ICL and present a case with cytologic, immunocytochemical and ultrastructural features. CASE: A 15-year-old female was admitted with a left thyroid mass. Ultrasound examination revealed a well-defined tumor in the left lobe of the thyroid. Fine needle aspiration cytology showed mainly dispersed spindle cells with oval nuclei and some polymorphic or triangular tumor cells. The tumor cells containing ICL were noted at high magnification. The ICL contained sparse microvilli and abundant granular material with dense, round bodies on ultrastructural sections. Immunocytochemically, these tumor cells were positive for calcitonin and carcinoembryonic antigen (CEA). Moreover, CEA was recognized in the ICL with immunocytochemical staining. All tumor cells were negative for thyroglobulin. Pathologic examination confirmed the diagnosis of medullary carcinoma of the thyroid gland. CONCLUSION: MCT can include ICL with granular material containing CEA.

Adolescent↗
PubMed1997

[Modern diagnostic methods for thyroid gland diseases].

The paper overviews the role of diagnostic procedures in evaluating patient with thyroid gland disease. It focuses on the diagnostics of functional disturbances and on the modern approach to the nodular goitre. The role of supersensitive, immunoenzymatic assay of TSH (sTSH) in the diagnostics of functional disturbances in underlined, particularly in subclinical course of thyroid gland diseases, or in diagnostically difficult cases. The complimentary role of tests' triangle-ultrasound, scintigraphy and fine needle biopsy in the evaluation of focal changes of the thyroid (nodular goitre) is discussed and the diagnostic algorithm of patient's qualification to surgery is proposed.

Algorithms↗
PubMed1987

Neurokinin A and galanin in the thyroid gland: neuronal localization.

The distribution of neurokinin A (NKA) and galanin (GAL) in the thyroid gland of several species was examined with immunocytochemistry. NKA-immunoreactive fibers were observed around blood vessels and follicles in all species examined, whereas GAL-immunoreactive fibers were found in mice and rats only. NKA-containing fibers were more numerous than GAL-containing fibers. All thyroid NKA-containing fibers harbored substance P (SP), and the majority of them stored calcitonin gene-related peptide (CGRP) as well. Most thyroid GAL-immunoreactive fibers contained NKA, SP, and CGRP; in a minor population GAL coexisted instead with vasoactive intestinal peptide. Cervical vagotomy (extirpation of the nodose ganglion) reduced the number of NKA- and GAL-containing fibers in the thyroid by approximately 50%. The jugular ganglion and cervical dorsal root ganglia are fairly rich in GAL-, NKA/SP-, and CGRP-containing cell bodies, which presumably represent the source of GAL-, NKA/SP-, and CGRP-containing fibers in the thyroid. The thyroid ganglion is rich in vasoactive intestinal peptide nerve cell bodies, which presumably project to the thyroid gland; a minor proportion of these cell bodies was found to contain GAL as well. Although the distribution of NKA and GAL fibers in the thyroid suggests that the two peptides are involved in the regulation of local blood flow and follicular cell activity, neither NKA nor GAL had any influence on thyroid hormone release as tested in conscious mice.

Animals↗
PubMedDate not supplied

[Comparative effects of desiccated thyroid gland and sodium salt of L-thyroxine in the treatment of hypothyroidism].

The studies comparing the actions of dried thyroid gland (Thyroideum-Polfa) with L-thyroxine sodium (L-T4) were carried out in 20 female patients with hypothyroidism, including 19 patients with the primary hypothyroidism and 1 patient with hypothyroidism secondary to pituitary deficiency. Administration of the dried thyroid gland did not normalize blood serum T4 an TSH in any patient. Normal serum T4 or even slightly increased was achieved in all patients treated with L-T4. Serum TSH was normalized in 17 patients with the primary hypothyroidism. The following conclusions have been drawn: 1. Dried thyroid gland (Thyroideum-Polfa) is ineffective in the treatment of hypothyroidism. 2. Serum TSH remains elevated despite normal serum T3 in cases of the primary hypothyroidism with decreased serum T4 levels. 3. Sodium salt of L-thyroxine should be used for the treatment of hypothyroidism. 1-Triiodothyronine sodium may be used as an adjuvant therapy.

Adult↗
PubMed2002

[Intraoperative electrophysiological monitoring of the recurrent laryngeal nerve in thyroid gland surgery--a prospective study].

INTRODUCTION: In the last few years the use of intraoperative electrophysiological monitoring of the recurrent laryngeal nerve (RLN) in thyroid gland surgery has become more and more important. PATIENTS AND METHOD: In a prospective study 223 nerves at risk in 116 patients were monitored with the Neurosign(R)100 (Fa. Magstim Ltd., UK). We used intramuscular needle electrodes inserted into the vocal muscle through the conic ligament. Practicability, complications, acceptance and predictive value of the method were documented. Recurrent nerve palsy rate and complications were compared with a control group operated upon without monitoring. RESULTS: The intraoperative delay using this method was on average 8.9 minutes. There were problems with monitoring equipment avoiding use in 6.4 %. In 2 cases (1.7 %) an accidental lesion of endotracheal tube cuff was found related to malpositioning of the needle and in 7.7 % a hematoma of the vocal cords was observed. 73.3 % of the surgeons accepted the method to identify and control the nerve integrity. False-positive and false-negative signals may occur. In cases of a final real stimulus response a regular vocal cord motility was found in 95 %. If a nerve conduction block was noted an immobility of ipsilateral vocal cord was diagnosed postoperatively in 50 %. There was no decrease in transient recurrent palsy rate using monitoring (10.7 % vs. 9.6 % without monitoring) but in permanent paralysis (1.8 % vs. 3.0 %). CONCLUSIONS: It may be concluded that intraoperative electrophysiological monitoring of the RLN is a simple and accepted method with low complications reducing the incidence of permanent RLN palsy rate. We found the monitoring especially useful for operations of recurrent goiter and carcinomas of the thyroid gland as well as for learning thyroid gland surgery.

Attitude of Health Personnel↗
PubMed1976

[Age dependent morphokinetics of the thyroid gland. Histochemical, morphometric, light-microscopical and functional investigations (author's transl)].

The aim of the animal experiments was to investigate the question of the age dependence of the morphokinetic reactions of the thyroid gland under standardised conditions. Through the administration of pharmaceutical substances, it was possible to produce defined functional states of the thyroid in the various age groups. Materials and Methods 700 Albino rats of the Chbb: Thom (SPF) strain, age 0 days (newborn) to 110 weeks, were used in the investigations. The animals were divided into 4 groups each with 12 subgroups according to age. One group received 300 mug/kg/day triiodothyronine (T3) for 10 days for the suppression of thyroid gland function, one group received methylthiouracil (MTU) for 10 days to block hormone synthesis, and one group received 10 IU/kg/day thyrotrophic hormone (TSH) for 5 days to stimulate the gland. The control group received distilled water. Investigations carried out: Protein-bound iodine (PBI) and total thyroxine (T4) in the serum; enzyme histochemical demonstration in the thyroid of alkaline phosphatase (a. Ph.), acid phsophatase (s. Ph.), cytochrome oxidase (Cyt. ox.), succinic dehydrogenase (SDH), iso-citric acid dehydrogenase (ICDH), ATP-ase and nonspecific esterase. The height of the follicular epithelium and the nuclear diameters of the follicular epithelial cells were estimated in embedded material. Light-microscopical investigations were performed using Paraplast and Epon embedded material. Staining methods: H. and E., Azan, PAS-alcian blue, Elastica-van Gieson, Perl's method for iron, Gomori's reticulin stain and von Kossa's calcium method (in aged animals). Staining of semithin sections with toluidine blue, Movat's stain and Morgenroth's stain. Biometric analysis of results: Simple and two factor analysis of variance, Scheffé test, graphic demonstration after polynomial fitting of third to fifth degree. Results a. Histochemical findings In the thyroid gland, all the above mentioned enzyme histochemical reactions studied show a mostly distinct age dependent relationship in the intensity of enzyme activity. Age dependent changes in the histo-topochemical behaviour of individual reactions are also demonstrable on light-microscopical examination. In control animals at the time of birth, alkaline phosphatase and cytochrome oxidase react moderately, the others weakly. With hydrolases the activity of alkaline phosphatassr remains at a moderate level throughout the life span, while acid phosphatase and ATP-ase show a marked increase up to puberty, and the reaction is still mnd I.C.D.H. an increase during the growth period, a marked response in middle life, and a lessening of activity in ageing animals can be demonstrated. Cytochrome oxidase increases up to the seventeenth week of life, and then decreases in older animals. The activity of nonspecific esterase increases up to the eleventh week, remains at a high level up to the forty fourth week and then lessen after one year of life...

Age Factors↗
PubMed2006

The interaction of the thyroid gland, pineal gland and immune system in chicken.

The interaction of immunological system, thyroid and pineal gland was studied in 5-week old males of Gallus domesticus. Several morphometrical parameters in pineal and thyroid glands were measured after bird immunization with human red blood cells and/or treatment with melatonin or seduxen, melatonin receptor blocker. The peak of the thyroid activity was found on Day 7 after immunization. The immune system appears to directly activate the thyroid gland only in the presence of certain level of melatonin. We suggest that the melatonin mechanism of action includes the enhancement of thyroid gland sensitivity to immune factors. Seduxen prevented the stimulatory influence of the immune system on the thyroid gland.

Animals↗
PubMedDate not supplied

[Autoimmune processes in diseases of the thyroid gland].

The previous knowledge related to auto-immune occurrences in thyroid gland disease are described in the review, showing main antigens, auto-antibodies, the inclusion of humoral and cellular immunity in the most frequent thyroid gland diseases. In spite of many learnings, which are broadened every day, the exact sequence of events and roles of external factors in genetically predisposed persons is still unknown. An identification of auto-antibodies gives direct evidence about the auto-immune process, as they are present among the majority of patients with Graves' hyperthyroid and Hashimoto's thyroiditis. Immuno globulins, created by plasma cells, linked with cytokinins from lymphocyte CD4 T, engage the cell auto-immune reaction in these diseases. Being acquainted with all events in the auto-immune process, we can understand better why these frequent diseases occur, why do they have chronic and recidivous course, why they are more frequent with women and within some families, and why they enable us to make a better diagnosis and treatment of these patients.

Autoantibodies↗
PubMed1977

Embryologic origin of various epithelial cell types in the thyroid gland of the rat.

Ventral pharyngeal outpocketings and ultimobranchial outpocketings from the 14-day-old fetus of the Fischer rat were isolated before they fused to form thyroid glands. The outpocketings were implanted into different kidney capsules of adult male Fischer rats, and were allowed to grow for several months. Transplants were then excised and examined by electron microscopy. The ultimobranchial outpocketing gave rise to two types of follicles. One contained ciliated cells, cells with an abundant agranular reticulum, U cells with basal hemidesmosomes, and two types of cells with secretory vesicles. The other contained C cells separated from the follicular lumen by a single flat fiber-containing cell. The ventral outpocketing formed typical thyroid epithelium making up the usual thyroid follicles differing from follicles in the thyroid in situ by the absence of C cells. These follicles were functional as determined by autoradiographic studies with 125I but differed from thyroid follicles in situ with respect to size distribution. The results suggest that (1) in the adult thyroid gland the C cell in the usual follicle is an ultimobranchial contribution and (2) the so-called ultimobranchial follicle is ultimobranchial in origin but that the typical thyroid epithelium in mixed follicles of U cells and typical thyroid epithelium is a ventral contribution. The reason for the absence in the thyroid gland in situ of the variety of other cell types observed in ultimobranchial transplants is unknown.

Animals↗
PubMed2002

Prenatal thyroid gland in sheep with regard to the presence of isthmus.

We studied the embryonal thyroid gland in 18 foetuses of sheep of Slovac merino breed by light microscopy in the period from 32nd to 36th day of evolution. We found that in the majority of sheep foetuses, the thyroid gland consists of two separate lobes and their structure was the same during the afore-mentioned period. Parenchyma, composed of solid cell networks or cell groups in the form of nests, was irregularly divided by septa, containing embryonal blood vessels. Almost all cases of this experiment showed slight asymmetry of lobes. In one case the asymmetry reached a considerable proportion - nearly the length of one lobe. Glandular isthmus was presented in only eight cases from 18 foetuses. We did not find fibrous isthmus in any case.

Animals↗