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Biomedical subjects

L Stefăneanu

Publications and source records attributed to L Stefăneanu.

15 recordsLinked to original sources
PubMed1986

Immunohistochemical localization of thyroglobulin (Tg), thyroxine (T4), and triiodothyronine (T3) in thyroid diseases.

Thyroglobulin (Tg), thyroxine (T4), and triiodothyronine (T3) were detected by the immunoperoxidase method in 51 cases of the following thyroid diseases: euthyroid goiter, Basedow's disease, Hashimoto's thyroiditis, folliculo-papillary carcinoma, follicular carcinoma, anaplastic carcinoma, and medullary carcinoma. Tg, T3, and T4 are present in most of the examined disorders, excepting anaplastic and medullary carcinoma. The pattern of Tg, T3, and T4 distribution between the cases of a benign lesion is rather similar; Tg and T4 are localized both in the epithelium and the colloid; T3 is disposed especially in the follicular cells. The pattern of Tg, T3, and T4 distribution in differentiated carcinomas is more heterogeneous. In half of the cases, T3 distribution resembled that of Tg. In 2 cases, a predominance of T4 was noted. In the other specimens, T3 and T4 showed a weak or a negative immunostaining.

Adenocarcinoma↗
PubMed1977

Cytoenzymologic activities of some oxidreductases in thyreopathies.

The authors studied in cryostat sections and in smears from thyroid aspirates the cytoenzymic pattern of the following thyreopathies: euthyroid goitre, GRAVES' disease, hyperthyroidized goitre, HASHIMOTO's thyroiditis and folliculo-papillary carcinoma. A biochemical study was simultaneously performed. According to the investigated thyreopathies the highest enzymic activity was found in the GRAVES' disease especially for peroxidase, glucose-6-phosphate dehydrogenase and succinate dehydrogenase. Lactate dehydrogenase showed a great activity in thyroid cancer. The lowest activity was found in the HASHIMOTO's thyroiditis with strong fibrosclerosis. The same pattern was found in thyroid smears from fine needle aspirates. The biochemical analysi revealed a strong parallelism with cytoenzymic results. The isozymic pattern of lactate dehydrogenase showed no significant differences between the thyreopathies.

Female↗
PubMed1975

Histopathologic observations on thyroid carcinoma with amyloid stroma.

The authors describe histopathologic aspects in ten cases of thyroid carcinoma with amyloid stroma. This form of cancer represents 3.4% of all the thyroid cancer cases in the last five years in the Institute of Endocrinology. Microscopic examination reveals a polymorphous picture alongside with amyloid deposits. The authors attribute to the tumor cells an important role in producing thyroid amyloidosis.

Amyloidosis↗
PubMedDate not supplied

A pathomorphic study of chronic thyroiditis.

The authors studied the pathomorphy of 364 cases of chronic thyroiditis including Hashimoto's thyroiditis (67 cases), Hashimoto's thyroiditis associated with thyroid cancer (21 cases), De Quervain's thyroiditis (10 cases), tuberculous thyroiditis (6 cases), and 260 cases of focal thyroiditis without manifest clinical symptoms appearing in 10% of euthyroid polynodular goitres. A personal classification of chronic thyroiditis is presented. The high incidence (24%) of association between thyroid cancer and the fibrous type of Hashimoto's thyroiditis is emphasized. A morphometric investigation showed the highest sclerosis percentage in De Quervalin's thyroiditis.

Adolescent↗
PubMedDate not supplied

Histopathology of some carcinomatous and pseudocarcinomatous aspects of the thyroid.

The authors studied the histopathology of some true carcinomatous and pseudocarcinomatous aspects of the thyroid. Some peculiar aspects occuring after therapy with thyreostatics are underlined: papillary structures, giant polymorphous, hyperchromic or light vesicular nuclei. These lesions are not to be confused with true neoplastic pictures. The criteria in discriminating between thyroid adenoma and follicular adenocarcinoma are also discussed.

Adenocarcinoma↗
PubMedDate not supplied

Scanning electron microscopy of euthyroid goiter and Graves's disease.

The scanning electron microscopy of 5 euthyroid polynodular goiters and 5 cases of Grave's disease was studied. In the polynodular goiter most of the follicular cells were flattened. Small, coarse, irregular microvilli were noticed. In the Grave's disease cases the follicular cells were columnar, covered with long microvilli. Marked epithelial infoldings were found. Thick bundles of collagen surrounded the follicles, especially in the polynodular goiter.

Adult↗
PubMedDate not supplied

Cytochemistry--a tool in thyroid pathology.

The authors studied the cytoenzymic pattern of various thyropathies. The highest enzymic activity was found in Graves' disease, especially for peroxidase, glucose-6-phosphate dehydrogenase and succinate dehydrogenase. Lactate dehydrogenase showed a great activity in thyroid cancer. The lowest activity was found in Hashimoto's thyroiditis with strong fibrosclerosis. The cytophotometrical data in form of histograms showed dextro-deviation of curves and plurimodal, irregular aspects of nuclear volumes and nucleic acid content in agreement with the cytological features of the investigated thyropathies. The linear regression analysis between the nuclear volumes and the nucleic acid content disclosed a diminished correlation in thyroid carcinoma and in euthyroid goitre.

Acid Phosphatase↗
PubMedDate not supplied

Immunohistochemistry of thyroid hormones as a functional parameter in thyroid pathology.

The authors study by means of immunoperoxidase method the pattern of thyroglobulin, triiodothyronine and thyroxine distribution in 58 cases of thyroid disorders: 15 euthyroid goiters, 10 Graves' disease, 7 Hashimoto's thyroiditis, 11 folliculo-papillary carcinomas (6 primary tumors and 5 lymph node metastases), 8 follicular carcinomas, 4 anaplastic carcinomas and 3 medullary carcinomas. Thyroglobulin, triiodothyronine and thyroxine were present in most of the thyroid disorders, excepting anaplastic and medullary carcinomas. Thyroglobulin and thyroxine were localized both in the follicular epithelium and in the colloid, whereas triiodothyronine was present especially in the follicular cells. The thyroid hormones distribution in benign lesions is rather similar. In carcinomas, the pattern of thyroglobulin, triiodothyronine and thyroxine is more heterogeneous, but generally the triiodothyronine distribution is similar to that of thyroglobulin. In some carcinomas, triiodothyronine and thyroxine showed a weak or negative immunostaining. The immunoperoxidase method is a valuable tool in the study of functional disturbances in the thyroid pathology and in the diagnosis of thyroid carcinoma metastases as well. Positive thyroid hormones staining clearly indicates the thyroid origin of metastases.

Histocytochemistry↗
PubMedDate not supplied

Immunohistochemical demonstration of myoglobin (Mb) in pathological thyroid tissue. Correlation with thyroglobulin (Tg), thyroxine (T4) and triiodothyronine (T3) distribution.

Myoglobin (Mb) was investigated by the immunoperoxidase method (PAP) in 48 cases of thyroid diseases including euthyroid goiter, Graves' disease, folliculo-papillary carcinoma, follicular carcinoma, anaplastic carcinoma and medullary carcinoma. Mb was demonstrated in most of the pathological thyroid tissues. In benign lesions, Mb is diffusely disposed throughout the cytoplasm in moderate quantities and only occasionally predominates at the apical border of thyreocytes. Generally, in differentiated carcinomas, the intensity of Mb immunostaining is moderate or weak. In some cases a predominance of Mb at the apical border of the malignant thyreocytes was noticed. In anaplastic and medullary carcinoma no Mb was detected. We compared the pattern of Mb distribution with that of thyroglobulin (Tg), triiodothyronine (T3), and thyroxine (T4) on serial or semiserial sections. The localization of Mb agreed relatively well with that of thyroid hormones. The distribution of Tg, especially in carcinomas did not correspond with that of Mb. Our results could suggest the implication of Mb as a source of oxygen in the thyroid peroxidase system rather than in exocytotic-endocytotic processes.

Carcinoma↗
PubMedDate not supplied

The myocardial microangiopathy in human and experimental diabetes mellitus. (A microscopic, ultrastructural, morphometric and computer-assisted symbolic-logic analysis).

The following microscopical aspects were found in the small intramural arteries in the myocardium of 30 diabetic patients: endothelial proliferations with focal protuberances leading to partial narrowing of the lumen, increased thickness of the arterial wall due to fibrosis and accumulations of neutral mucopolysaccharides: alteration of elastic fibres. Morphometrically, the arterial wall thickness and the arterial diameter were increased whereas the arterial density decreased in the diabetic heart. In 25 rats with streptozotocin-induced diabetes the small intramyocardial arteries were investigated at 11 to 40 weeks of diabetic state. Using morphometrical analysis a constant increase of arterial wall thickness paralleling the diabetes duration was found. Microscopically, the lesions consist in endothelial proliferation with bridging across the vascular lumen and slight perivascular and diffuse fibrosis. Ultrastructurally, the capillary basal lamina was thickened in the diabetic myocardium. In order to investigate the morphometrical data we used symbolic-logic as a decision method, by applying an original computer program based on the Quine-McCluskey algorithm. All our results together with the final symbolic-logic expression suggest that damage of the small intramyocardial arteries plays an important role in the pathogenesis of diabetic cardiomyopathy.

Aged↗
PubMedDate not supplied

An electron-microscopic study of human thyroid cancer.

Authors studied the ultrastructural characteristics of the following thyroid cancer: papillary carcinoma, follicular carcinoma, undifferentiated carcinoma and medullary carcinoma. Some specific ultrastructural-functional correlations for each type of thyroid cancer could be established. Papillary and follicular carcinoma had some common features: larger nuclei than in benign lesions, a highly increased number of mitochondria, a reduced endoplasmic reticulum, cell junctions between the cells and an intact basal lamina. In addition, papillary carcinoma presented stage I and stage II nuclear inclusions, and nuclear invaginations that contained cytoplasm. The higher malignancy of follicular carcinoma compared with that of papillary carcinoma was assigned to less differentiated areas corresponding to the compact fields. Undifferentiated carcinoma consisted of large pleomorphic cells (spindle and giant cells) with abundant mitochondria, a flat rough endoplasmic reticulum, scanty secretory granules and lysosomes, cell junctions, all suggesting their common epithelial origin. Ultrastructure of medullary carcinoma contributed to the explanation of the amyloid origin and of granule types in correlation with hormone storage in cells.

Adenocarcinoma↗
PubMedDate not supplied

Ultrastructural pathology of the adrenal gland in Cushing's syndrome.

Authors studied the ultrastructural pathology of Cushing's syndrome. Some specific features correlated with the pathological aspects of the adrenals could be found. In the hyperplastic adrenal cortex the cytoplasm contains a rich smooth endoplasmic reticulum and numerous mitochondria. Increased lipid-pigment complexes were also found. The clear cell adenomas showed large lipid vacuoles. In the compact cell adenomas the mitochondria are of variable size and the smooth endoplasmic reticulum is well developed; the pigment bodies are frequent. The nuclei and especially the nucleoli are increased in size. In the adrenal carcinoma the nuclear and nucleolar alterations are still more evident. A marked pleomorphism of mitochondria was noticed. The behaviour of the steroidogenic activity in both tumoral and hyperplastic adrenal glands can be assessed using the ultrastructural picture of the agranular endoplasmic reticulum and of the mitochondria as functional parameters.

Adrenal Cortex↗
PubMedDate not supplied

Electronoptical aspects of the thyroid cold nodule.

The authors studied the ultrastructure of benign and malignant forms of the thyroid cold nodule. In the benign cold nodule the most striking feature was an irregular endoplasmic reticulum with large cisternae and scarce ribosomes, this meaning an impaired protein synthesis. Frequent lysosomes and phagolysosomes occurring in the apical zone of the cell were present. In the malignant form of the cold nodule, nuclear abnormalities, a reduced endoplasmic reticulum and a highly increased number of abnormal mitochondria were found. The increased number of mitochondria in the carcinoma is a compensatory reaction to the frequent abnormalities found in these organelles. No transitional ultrastructural stages could be established between benign and malignant cold nodules. In practice the nature of a cold nodule is established by thyroid surgery and histologic examination.

Adenoma↗