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Biomedical subjects

S Z Stefanko

Publications and source records attributed to S Z Stefanko.

36 records · Page 2Linked to original sources
PubMed1986

High incidence of somatostatin receptors in human meningiomas: biochemical characterization.

Thirteen human meningiomas were tested for their content of specific somatostatin (SRIH) receptors using an in vitro binding assay with meningioma homogenates as well as receptor autoradiography. All tumors had measurable amounts of somatostatin receptors. Receptor density, however, greatly varied among the tumors, ranging from low levels to more than 400 fmol/mg protein. Seven tumors, biochemically characterized in detail, had saturable and high affinity receptors [mean Kd, 1.10 +/- 0.42 (+/- SEM) nM], with pharmacological specificity for SRIH resembling the noncentral nervous system type of SRIH receptor. There was no correlation between the density of SRIH receptors and the density of progestin receptors measured in parallel. The presence of SRIH receptors in meningiomas was completely unexpected, and their role unknown. If the receptors can mediate antiproliferative properties in meningiomas, as has been suggested to be the case for such receptors in other endocrine tumors, the present data could be of potential therapeutic interest.

Adult↗
PubMed1985

Oncocytic variant of choroid plexus papilloma.

Two cases of oncocytic plexus papilloma are presented which were in the fourth ventricle and cerebello-pontine angle in women aged 70 and 63 years, respectively. The cytoplasm of the transformed tumor cells was enlarged, eosinophilic, and granular; and it was characterized ultrastructurally by innumerable mitochondria. Most of them had lamellar cristae, a clear matrix, and contained dense granules. These 'oncocytes' are identical with oncocytes of the human thyroid, parathyroid, bronchi, kidneys, adrenals, salivary gland and myocardium, and non-neoplastic choroid plexus epithelium. As far as we know, this is the first report of an oncocytic variant of the choroid plexus papilloma. Two unusual cases are described.

Aged↗
PubMed1985

Different responses of growth hormone secretion to guanfacine, bromocriptine, and thyrotropin-releasing hormone in acromegalic patients with pure growth hormone (GH)-containing and mixed GH/prolactin-containing pituitary adenomas.

There is great variability in the GH secretory responses to different stimuli in patients with acromegaly. In the present study, we compared the effects on GH secretion of two compounds (bromocriptine and TRH), which presumably act directly at the pituitary level, with the effect of the centrally acting alpha-adrenergic agonist guanfacine in 14 untreated acromegalic patients. These in vivo responses of GH release were correlated with the results of immunocytochemical studies of the pituitary adenomas. In nine patients with pure GH-containing adenomas, GH secretion was suppressed by bromocriptine by more than 50% in one patient, while TRH stimulated GH release by more than 100% in another patient. Guanfacine (2 mg, orally) did not elicit a change in circulating GH levels in any of these nine patients. In the group of five patients with mixed GH/PRL-containing adenomas, however, bromocriptine suppressed GH levels by more than 50% in all patients, and TRH stimulated GH release by more than 100% in four of them. Guanfacine stimulated GH secretion significantly in four of these five patients. Guanfacine inhibited GH secretion significantly in five other acromegalic patients who had been treated 5-10 yr previously by external pituitary irradiation. We conclude that in acromegaly, the presence of PRL within the GH-secreting pituitary adenoma makes GH secretion more sensitive to bromocriptine and TRH, while normal sensitivity to hypothalamus-mediated stimulation (alpha-adrenergic agonist) is retained to some extent. In contrast, pure GH-secreting tumors responded little or not at all to bromocriptine, TRH, or guanfacine.

Acromegaly↗
PubMed1983

Relationship between cytological picture and hormone secretion by human pituitary adenomas in cell culture.

In 22 endocrinologically active hypophyseal adenomas the relationship between the biological behaviour and the cytological picture was investigated. There was a positive correlation between the atypia of the cells in the cytograms and hormone secretion of the tumour cells in vitro and the clinical aggressiveness. Cytological examination gave a better insight into the biological properties of these tumours than histological methods.

Adenoma↗
PubMed1983

Hereditary neuralgic amyotrophy. Clinical, genetic, electrophysiological and histopathological studies.

Clinical, genetic, electrophysiological and histopathological studies in a four-generation family with hereditary neuralgic amyotrophy (HNA) are described. Clinically two kinds of attack could be distinguished: (1) the classical type with pain and weakness lasting for weeks to months, leaving atrophy and sometimes residual weakness; 2) attacks consisting of recurrent pain and weakness lasting for a few days and occurring about once a week for several months, also resulting in persisting atrophy and weakness. Genetically a strong association was found between HNA and hypotelorism, probably due to pleiotropism of one single gene. Close linkage with any of 29 genetic markers was not present. The electrophysiological findings indicated that a local process in the brachial plexus, possibly demyelination or a conduction block, was the primary pathophysiological mechanism. Nevertheless, the sural nerve of the index case, biopsied 5 months after the onset of an attack, showed a decreased number of myelinated nerve fibres per cross-sectional area. Apparently, other parts of the peripheral nervous system may be affected subclinically in an attack of brachial plexopathy. The central and peripheral nervous system of his mother, 30 years after her last attack of HNA, showed only nonspecific changes. Tomacula were not seen in either case. HNA and hereditary liability to pressure palsies (HLPP) are distinctly different disorders.

Adolescent↗
PubMed1983

Parinaud's syndrome.

Five cases of a tumour in the quadrigeminal area have been described, 4 of which could be verified by autopsy. In 2 cases with a metastasis in the tegmentum of the mesencephalon, a Parinaud syndrome was present. In 2 other cases, however, with extensive destruction of the quadrigeminal plate and of the posterior commissure this syndrome was not present. In the 5th case, with a big vascular tumour of the pineal area, disturbances of eye movements and pupils were also lacking. From these observations we may conclude that (1) destruction of the quadrigeminal plate has no influence upon vertical eye movements. (2) destruction of the posterior commissure, in combination with the quadrigeminal plate, is not always followed by disturbances of vertical eye movements. In man it is still not clear which structures are responsible for the performance of vertical eye movements.

Aged↗
PubMed1983

Autosomal recessive spino-olivo-cerebellar degeneration without ataxia.

Five adult siblings from a sibship of ten suffering from an external ophthalmoplegia with a spastic paraplegia are reported. In addition, optic nerve atrophy was present in three of the patients and dementia in two; extrapyramidal signs and cerebellar ataxia were found only in one patient. Contrary to earlier studies of patients with comparable neurological signs the pattern of inheritance was autosomal recessive. Neuropathological investigation of the index case, who had never shown ataxia, nevertheless showed demyelination of the spinocerebellar and the olivocerebellar pathways, and also a severe loss of Purkinje cells, of cells in Clarke's column and in the inferior olives. The dentate nucleus was severely gliotic but showed no cell loss. Earlier neuropathological investigations of this disorder, but with an autosomal dominant heredity, were incomplete. It is concluded that the five siblings of this family have a unique autosomal recessive disorder, which should be considered a distinct entity.

Aged↗
PubMed1983

The role of prolactin in the inhibitory action of bromocriptine on growth hormone secretion in acromegaly.

UNLABELLED: Bromocriptine treatment results in clinical improvement and inhibition of plasma GH levels in only part of the acromegalic patients. The possible role of the simultaneous presence of Prl and GH in GH-secreting pituitary adenomas was investigated with regard to the inhibitory action of bromocriptine on GH secretion and the paradoxical increase of GH release in reaction to TRH. Surgically obtained pituitary tumour tissue from 35 consecutive acromegalic patients was studied immunohistochemically. In 21 patients no Prl was present in the tumour tissue. These patients had normal plasma Prl levels. In the other 14 patients Prl was present in the tumour tissue. Hyperprolactinaemia was found in 10 of these 14 patient. Plasma GH levels from 2 till 10 h after the administration of 2.5 mg bromocriptine measured before operation were significantly more suppressed in the patients with mixed GH/Prl-containing than in those with pure GH-containing pituitary adenomas, being 38 +/- 4% and 65 +/- 4% of basal values, respectively (P less than 0.01). The response of GH to TRH, however, did not differ significantly between the two groups. CONCLUSIONS: 1. In about 70% of patients with 'mixed' GH/Prl containing adenomas, hyperprolactinaemia is present. 2. The simultaneous presence of Prl and GH in a GH-secreting pituitary tumour increases the sensitivity of GH secretion to bromocriptine. 3. The plasma Prl level is of value to predict which patients with acromegaly are likely to respond to bromocriptine with an inhibition of GH secretion.

Acromegaly↗
PubMed1981

Papillary meningioma.

Six cases of papillary meningioma are described. Five patients are still alive 2 months, and 2, 7, 8 and 14 years after the operation respectively. No metastases or recurrences have been noted. One patient died from an intercurrent disease 2 years after operation. In all cases the papillary pattern was associated with one of the typical well known forms of meningioma. One case showed histologic features of anaplasia, i.e.: local high cellularity accompanied by mitotic activity and pleiomorphism. Only one or two features suggestive of a higher growth dynamism were noted in the other cases. The mechanism of the papillary structures is discussed. Vasotropism and a feeble cohesion between the cellular perivascular "crowns" are thought to be responsible for the papillary pattern which should be interpreted as a secondary phenomenon. It appears likely that the papillary pattern of meningioma is not always an expression of anaplasia when no other clinical and histologic signs of malignancy are present.

Animals↗
PubMed1981

Autonomic nerve calcification and peripheral neuropathy in olivopontocerebellar atrophy.

This report concerns an unusual form of olivopontocerebellar atrophy (OPCA) of adult onset, inherited as an autosomal dominant. We examined 5 patients in one generation and performed neuropathological investigations in 3 of these. The clinical and pathological features were different from those of OPCA types I to V. Apart from olivopontocerebellar degeneration, there was dementia in 4, massive atrophy of the spinal cord in 3, and focal degeneration of the optic nerves in at least 1 case. The most remarkable findings were, however, the involvement of the peripheral nervous system and the abundant intrafascicular calcification in sympathetic nerve fibers and in their ganglia.

Atrophy↗
PubMed1980

Intramedullary metastasis.

Three cases of intramedullary metastases and one of a metastasis into the medulla oblongata are described. In two cases the primary tumour was a bronchial carcinoma and in one case a carcinoma of the breast. In one patient a primary tumour could not be found. The literature on this condition is reviewed and the difficulties of clinical diagnosis are discussed. The question remains unanswered as to the mechanism by which these tumour-cells reach the spinal cord and there is, as yet, no satisfactory explanation for the relative rare occurrence of these metastases.

Aged↗
PubMed1980

Failure of clinical remission after transsphenoidal removal of a microadenoma in a patient with Cushing's disease: multiple hyperplastic and adenomatous cell nets in surrounding pituitary tissue.

A patient with Cushing's disease is described who underwent transsphenoidal adenomectomy of a basophilic microadenoma with a diameter of 3 mm. In a piece of surrounding normal pituitary tissue removed at operation, multiple small nests of adenomatous basophilic cells were found both in the adeno- and neurohypophysis. No clinical improvement was observed. Cortisol secretory rate, plasma ACTH, the absent response of plasma cortisol to insulin-induced hypoglycemia, and the responses of plasma cortisol to lysine vasopressin and TRH remained unchanged. The observations in this patient point to the presence of multiple ACTH-secreting adenomatous cell nests and microadenomas throughout pituitary gland and bring back into view the concept of primary stimulation of hypothalamic corticotropin-releasing factor as the primary derangement in some patients with Cushing's disease.

Adenoma↗
PubMed1979

The incidence of complications during pregnancy after treatment of hyperprolactinemia with bromocriptine in patients with radiologically evident pituitary tumors.

The course of pregnancy achieved after bromocriptine therapy is described in nine patients with radiologically evident prolactin-secreting pituitary tumors. In six patients no complications occurred. No changes in sellar size or secondary endocrine deficiencies developed. In three patients, however, complications developed between the 22nd and 24th weeks of pregnancy. Despite prior external pituitary irradiation, one patient developed transient bitemporal hemianopsia and one patient had apoplexy of the pituitary tumor with transient paresis of the left abducens nerve. A third patient developed parasellar expansion of the pituitary tumor with bone destruction and paresis of the right abducens and oculomotor nerves. After transsphenoidal surgery the paresis of both nerves disappeared. Microscopically, the tissue removed at surgery was a chromophobe adenoma with focal fibrosis and calcifications without recent hemorrhages. In the course of more than 100 pregnancies achieved in The Netherlands after bromocriptine therapy, five patients reportedly developed complications of the pituitary tumor. At present, patients in whom complications can be expected cannot be predicted by the size or configuration of the sella turicica or the magnitude of elevation of the plasma prolactin level. In two patients external pituitary irradiation did not prevent complications during pregnancy.

Adult↗
PubMed1979

Pinealoblastoma with retinoblastomatous differentiation.

A case of primitive neuroectodermal tumour originating from pineal parenchymal cells in a 2 1/2-year-old boy is described. The tumour exhibited divergent lines of differentiation including neuroblastic and photoreceptor differentiation, thus aligning it with neuroblastomas and with retinoblastomas. The tumour recalls the function of the pineal as a photoreceptor organ at an earlier stage of its phylogenesis.

Brain Neoplasms↗
PubMedDate not supplied

Basilar artery giant fusiform aneurysms caused by congenital defect of the internal elastic lamina and media.

Giant fusiform aneurysms of the basilar artery were found in a 6-year-old boy who subsequently died after rupture of the aneurysm, and in a 64-year-old man who showed signs of ischemia and compression of the brain stem. Autopsy disclosed strikingly similar abnormalities of the wall of the basilar artery, consisting of a defect of the internal elastic lamina and absence of the media. A congenital anomaly may play a role in the pathogenesis of this abnormality, in both young and some elderly patients.

Basilar Artery↗