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Biomedical subjects

C Hedinger

Publications and source records attributed to C Hedinger.

At least 73 records · Page 4Linked to original sources
PubMed1977

[Thyroid neoplasms before and after the prophylactic supplementation of table salt with iodine].

Fifty years ago Switzerland was known to be an endemic goiter area. Iodine deficiency has since been abolished by supplementation of table salt with iodine and increasing consumption of imported food. On the basis of the large number of specimens in the University Institute of Pathology in Zürich, an attempt has been made to determine whether morphological aspects of malignant thyroid tumors have changed in the intervening perified according to the WHO nomenclature of 1974. Comparison of these results with those of a similar study covering the period from 1962 and 1973 showed that the relative incidence of some tumor types definitely changed following the introduction of iodine prophylaxis. Follicular and anaplastic carcinomas have decreased in number, while papillary carcinomas are nowadays more frequent. The sex-ratio distribution has also been modified, female patients being now in the majority. Altogether the proportion of differentiated carcinomas has increased during the period from 1962 onwards, and their far more favourable prognosis will probably lead to retrogressive mortality rates for malignant thyroid tumors.

Adenocarcinoma↗
PubMed1977

[Pancreatic island cell tumors and their syndromes. I. Insulinomas, organic hypertinsulinism].

Based on a retrospective investigation of 61 surgical and autopsy specimens, the histopathologic features and clinical manifestations of islet cell tumors are described. In 33 cases reviewed in the first part of this study there existed indications of primary hyperinsulinism (HI) which was generally verified through fast test, stimulation tests or by insulin determination. In 25 cases the HI was caused by benign B-cell adenomas and in 3 cases by metastasizing carcinomas. In another case, polymacronesia of the pancreas with all patterns from abnormally structured islets to true adenomas was found. This patient was free of symptoms after subtotal pancreatectomy. In 4 other cases neither adenomas nor evident islet changes were identified; subtotal pancreatectomy cured only one patient. The insulinomas were surgically removed in 16 cases locally and in 9 cases by partial pancreatectomy. In two patients the adenomas were detected only after a second operation, and a third suffered from HI despite removal of two adenomas. The majority of insulinomas were characterized by staining and immunohistological technique, and a few electronmicroscopically. Two types of differentiation could be distinguished. The symptomatology of the three carcinoma patients was complex. Two of these patients suffered from severe ulcer disease reminiscent of Zollinger-Ellison syndrome. The third patient fell ill with erythema and other symptoms known from the "glucagonoma syndrome". These malignant tumors could only be incompletely characterized by staining, immunohistology and electronmicroscopy.

Abdomen, Acute↗
PubMed1977

[Vitelline components in teratomas and serum alpha-1 fetoprotein].

Serum alpha1-fetoprotein (AFP) had been determined in 31 patient with (mostly malignant) teratomas before or immediately after operation, and later in the evolution of 3 other cases with clinical evidence of recurrence or metastases. Without knowledge of these serum AFP levels, histological slides of the same 34 teratomas were reexamined, especially for the presence of yolk sac components. Two pure yolk sac tumors and 6 teratomas containing yolk sac structures were associated with serum AFP levels above 500 ng/ml. Teratomas without yolk sac structures were associated with normal serum AFP levels (i.e. 10-500 ng/ml) in 14 cases, and high serum levels (i.e. above 500 ng/ml) in one case. Histologic analysis of the 14 cases with slightly elevated AFP levels did not reveal tissue possibly responsible for the low but nevertheless abnormal AFP synthesis. High AFP levels, which are easily detectable by counter-current immunoelectrophoresis, are, however, highly specific for the yolk sac tumor or the yolk sac component of teratomas, and hence suggest that this extra-embryonic structure should be distinguished from other teratoma components.

Adolescent↗
PubMed1976

Histologic characteristics of insulinomas and gastrinomas. Value of argyrophilia, metachromasia, immunohistology, and electron microscopy for the identification of gastrointestinal and pancreatic endocrine cells and their tumors.

In a first step of our investigation the staining characteristics, especially the argyrophilia and metachromasia, of immunohistologically identified endocrine cells of the pancreatic islets and of the gastroduodenal mucosa were tested. These staining characteristics were then examined on insulinomas and gastrinomas. Contrary to normal B cells which generally react positively with aldehyde fuchsin and pseudoisocyanine but not argyrophilic with the Grimelius method, the neoplastic B cells give inconsistent results with conventional staining methods. Yet neoplastic B cells often show argyrophilic structures. Immunohistologically, most benign insulinomas are rich in insulin-containing cells, whereas in malignant types such cells are rare. The carcinomas, however, show a typical and distinct Grimelius argyrophilia. The tumor cells of gastrinomas are Grimelius argyrophilic and slightly metachromatic, as normal G cells, yet, contrary to A1 cells, they are only exceptionally stainable with the Hellerström method. Despite the great number of Grimelius positive tumor cells, generally only a few reacted with antigastrin serum. Nevertheless, the immunohistology is the most reliable method for the diagnosis of gastrinomas. Electron microscopic results are often difficult to interpret, since gastrinomas, as well as undifferentiated or malignant insulinomas, may predominantly contain atypical secretion granules.

Adenoma, Islet Cell↗
PubMed1976

[Glucagon producing adenomatosis of Islands of Langerhans with polyendocrine symptoms].

A patient in whom Cushing syndrome had been diagnosed at the age of 23 was found 14 years later to have subclinical diabetes mellitus, subcutaneous calcified fat tissue necroses, and hypergastrinemia suggesting Zollinger-Ellison syndrome. Histopathologic investigation revealed pancreatic adenomatosis of the glucagon producing A2-cells with accompanying B-cell hyperplasia, and hyperplasia of the adrenal cortex. The origin of the increased serum gastrin concentration in this patient is not yet known. The significance of A2-cell proliferation in Zollinger-Ellison syndrome and and in multiple endocrine adenomatosis is discussed.

Adipose Tissue↗
PubMed1975

[Classification of thyroid gland tumors in accordance with 1974 WHO nomenclature. Histological follow-up examination of 327 malignant thyroid gland tumors].

In 1974 an international histological classification of thyroid tumours was published by the World Health torganization, Geneva (WHO). It usefulness has been tested on the surgical specimens of 353 patients with malignant or probably malignant thyroid tumours analyzed at the Institute of Pathology, University of Zürich, from 1962 to 1973. 10 out of the 353 histologically reexamined cases had to be eliminated because of insufficient material. Of the remaining 343 tumours only 30 (10%) are difficult to classify according to the WHO nomenclature. 13 of these 34 tumours can be classified as differentiated carcinomas, though a clear distinction between follicular and papillary carcinoma is not possible. In 21 of the 34 doubtful cases the problems are of definite clinical importance: in 9 of them it cannot be decided on morphological grounds alone whether the tumor is malignant or not; 7 tumours cannot definitely be differentiated from metastases in the thyroid; and in 5 tumours it is not possible to determine the grade of differentiation. Considering that 90% of our tumours are easily classifiable, the WHO nomenclature represents - for pathologists as well as for clinicians - a distinct and simple basis for the classification of thyroid cancers. There is no need to overemphasize the difficulties of differential diagnosis in about 10% of the tumours since in only 6,2% of all tumours do these difficulties have real bearing on therapeutic procedure. Moreover, these problems concern questions of malignancy or metastases and are quite indipendent of any kind of nomenclature.

Age Factors↗
PubMed1975

Ultrastructure of developing germ cells in the fetal human testis.

Electron microscopic studies of the testis were performed on 12 human embryos and fetuses between 9 and 30 weeks post conceptionem. According to their ultrastructural features, the fetal germ cells could be divided into the following three stages of differentiation: 1) gonocytes, 2) intermediate cells, and 3) fetal spermatogonia. Sertoli cells were present among the germ cells in all the testes studied. The gonocytes showed the highest nucleo-cytoplasmic ratio. Their round nucleus contained a centrally located, prominent nucleolus. The cytoplasm displayed a well developed Golgi apparatus, lipid droplets and parallel arrays of short cisternae of the rough surfaced endoplasmic reticulum (rER). Microfilaments were numerous, particularly just beneath the cell membrane. The intermediate cells were found to extend several cytoplasmic processes and to contain a moderate number of long, branched and/or widened rER cisterna which were frequently connected to the perinuclear cisterna. Intermediate cells were often connected to one another by intercellular cytoplasmic bridges. The fetal spermatogonia also displayed cytoplasmic bridges. These cells showed the lowest nucleo-cytoplasmic ratio and more condensed nuclear chromatin. The mitochondria were situated close to the nucleus. Many of them were connected by a cementing substance. Lipid droplets and rER cisternae were rare in these cells. Infoldings of the inner nuclear membrane were often present in the gonocytes and in the intermediate cells, but were rarely observed in the fetal spermatogonia. Glycogen particles, polyribosomes, and chromatoid bodies ("nuage") were present in all the three germ cell types. With the maturation of the fetus, the number of gonocytes was found to decrease, whereas the number of fetal spermatogonia increased. The Sertoli cells also changed their ultrastructure, showing an increase in the number of rER cisternae, as well as of microfilaments, lipid droplets, and secondary lysosomes.

Age Factors↗