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Biomedical subjects

S Werner

Publications and source records attributed to S Werner.

At least 271 records · Page 15Linked to original sources
PubMed1985

Evidence of a circulating growth hormone stimulating factor other than growth hormone releasing hormone in a patient with pituitary tumour and acromegaly.

This study is a report on the growth hormone (GH) stimulatory effect of serum and plasma from a patient with notably active acromegaly due to a GH producing pituitary adenoma. Pituitary adenomatous tissue from 7 patients with GH producing adenomas, one with a prolactin (Prl) producing adenoma, one with a TSH producing adenoma, and one with a non-secreting adenoma, were cultured in vitro for 8-10 days. Media were changed every 48-72 h and contained Neumann Tytell buffer with the addition of 1) foetal calf serum, 2) patients' own serum or plasma, 3) serum or plasma from the patient with notably active acromegaly. GH release expressed as microgram GH/1/48-72 h between day 6 and 8 in culture did not differ when adenomatous tissue was cultured in buffer, foetal calf serum or the patients' own serum or plasma. In contrast, GH release was increased in 9/10 patients, when media contained serum or plasma from the patient with notably active acromegaly. This GH stimulatory effect was demonstrated in vitro in human pituitary adenomatous tissue from patients with pathological as well as normal GH secretion in vivo. Furthermore, this GH releasing plasma in a concentration of 10% increased GH release in cultures of dispersed rat anterior pituitary cells. In the same system, synthetic growth hormone-releasing hormone (GRF)-44 stimulated the release of GH in a dose-dependent manner. However, at all dose levels including maximally stimulating doses of GRF, an additive effect on GH release was seen with 10% of the GH releasing plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗
PubMed1985

DNA and S-phase representation in human growth hormone producing pituitary adenomas.

The DNA contents of 33 pituitary adenomas from patients with acromegaly were analysed with flow-cytofluorometry. Degrees of ploidy and the proliferation rate, expressed as percentage of cells in S-phase, were determined. The aim was to compare these morphological and functional tumour properties with clinical and laboratory parameters to establish a possible relation and to further elucidate the characteristics of these tumours. In 15 tumours (45%) diploid DNA pattern were found, while 18 (55%) showed varying degrees of aneuploidy. The frequency of cells in S-phase showed wide variations and were equally distributed in diploid and aneuploid tumours. Duration of symptoms, age at diagnosis, preoperative growth hormone (GH)- and prolactin (Prl)-levels, tumour size and grade of invasive tumour growth as determined by radiological estimations, did not correlate to ploidy or grade of proliferation. The lack of correlation between DNA pattern and proliferation rate in relation to clinical, laboratory and radiological parameters in tumours causing acromegaly contrasts to the documented relation between the degree of ploidy, cells in proliferation and grade of malignancy reported in tumours of other sites. The 55% aneuploid GH producing tumours indicate a certain malignant transformation. The high frequency of cells in S-phase in several GH secreting tumours completes the malignant morphological and functional cell properties. The benign character of tumours causing acromegaly is therefore in contrast to these findings. The lack of clinical significance of the DNA pattern and the frequency of cells in proliferation in GH producing tumours and the benign character despite malignant cell properties in most of these tumours are difficult to explain.(ABSTRACT TRUNCATED AT 250 WORDS)

Acromegaly↗
PubMed1984

Suckling in lactating women stimulates the secretion of insulin and prolactin without concomitant effects on gastrin, growth hormone, calcitonin, vasopressin or catecholamines.

The levels of growth hormone, vasopressin, prolactin, calcitonin, gastrin, insulin, epinephrine, norepinephrine and dopamine were measured in six lactating women during breast feeding. Prolactin levels increased in response to suckling as expected. In addition, insulin levels rose two-fold. No consistent changes were observed in the levels of the other hormones. It is suggested that the suckling related insulin release is either secondary to a reflexly induced activation of the vagal nerves or to the increased circulating levels of prolactin. Furthermore, it is suggested that the insulin release in response to suckling participates in the stimulation of milk production.

Adult↗
PubMed1984

Somatomedin A increments are diminished in acromegaly with concomitant hyperprolactinaemia.

The influence of prolactin (Prl) on growth hormone (GH) regulated somatomedin A (SMA) levels was studied in 30 patients with acromegaly before and after transsphenoidal pituitary surgery. Pre-operative GH levels were elevated in all patients and SMA levels in all but one patient. Eleven patients (33%) showed hyperprolactinaemia. There was no correlation between GH and SMA levels. Plasma GH did not differ in patients with GH and Prl producing adenomas compared to those with isolated GH hypersecretion. SMA levels, however, were significantly lower in patients with hyperprolactinaemia than in those with normal serum prolactin (P less than 0.001). After surgery GH decreased in all and SMA levels in all but one patient. Despite similar post-operative GH levels SMA decreased to significantly lower levels in patients with combined hypersecretion of GH and Prl compared to patients with normal prolactin levels (P less than 0.05). Nine of the 11 patients with hyperprolactinaemia showed normal Prl after surgery. The SMA levels in patients with acromegaly seem to be suppressed in patients with pre-operatively concomitant hyperprolactinaemia before as well as after adenomectomy regardless of the normalization of Prl. Our findings offer one explanation of the lack of correlation between SMA and GH levels in acromegaly.

Acromegaly↗
PubMed1984

[Brain sonographic findings in tuberous brain sclerosis. A comparison with roentgenologic images and pathologic-anatomic findings].

Ultrasound examination of a case of tuberous sclerosis is described. The results are compared to plain skull roentgenography, CT and pathological anatomical findings. Apart from the well known advantages of sonography (absence of radiation load, easy and quick practicability of control nearly without strain to the patient) the comparison shows that ultrasound offers a better chance to evaluate the structure of gliomatous masses and their relationship to the adjacent tissues. In connection with the pathological microscopical picture and the results of sonography we drew the conclusion that the paraventricular calcifications in CT so far described are most possibly gliomatous proliferations with densities around 100 HU. Using CT as a diagnostic tool alone it is not possible to distinguish between gliomatous proliferation and calcification in tuberous sclerosis.

Brain↗
PubMed1983

TSH-secreting pituitary tumor. A case report.

A pituitary tumor secreting thyroid-stimulating hormone (TSH) only was diagnosed in a 43-year-old man who originally showed signs and symptoms of thyrotoxicosis which recurred twice. Despite normal serum levels of T3 and T4, increased levels of TSH were diagnosed. The pituitary tumor was operated by the transsphenoidal approach. Morphological analysis of tumor tissue showed cellular pleomorphism and regressive changes. Nuclear DNA analysis showed that the tumor had only one cell line and an aneuploid DNA pattern. In vitro culture of tumor tissue confirmed that the tumor secreted TSH only.

Adult↗
PubMed1983

Oestrogen and testosterone effects on hormone secretion and cell morphology of human pituitary tumours.

Estradurin (a polymer of 17-beta-oestradiol) has an inhibitory effect on the synthesis/secretion of PRL. This effect is assumed to be caused by the strong inhibitory effect of the drug on phosphatases. With increasing time of low doses of Estradurin (0.001 micrograms/ml) in vitro, the inhibitory effect on PRL secretion was overcome and the synthesis/secretion of PRL increased. The secretion of GH was unaffected in all concentrations (0.001-0.1 micrograms/ml) except 1 microgram/ml. A stimulatory effect of 17-beta-oestradiol (0.01 micrograms/ml) on the synthesis/secretion of PRL was suggested by the tissue from one post-pregnancy pituitary. Short time organ cultures from prolactinomas or tumors with a concomitant secretion of GH and PRL show no changes of GH or PRL secretion following incubation with (0.001-0.1 micrograms/ml) of 17-beta-oestradiol. However, electron microscopy of 17-beta-oestradiol incubated specimens revealed an increased number of lysosomes and inclusion bodies in the cell cytoplasm. Incubation with testosterone (0.001-1 microgram/ml) cause inhibition of PRL synthesis/secretion in two of three prolactinomas. In GH secreting tumours testosterone did not effect PRL or GH secretion in vitro when compared with controls. The ultrastructural analysis of specimens in which a decrease of PRL synthesis/secretion had occurred showed myelin figures in the cell cytoplasm and accumulations of amorphous electron dense inclusion bodies.

Adult↗
PubMed1983

Oral contraceptive steroids do not promote the development or growth of prolactinomas.

Seventy women with prolactinomas, age 19-38 years, were studied in order to evaluate a possible relationship between the use of steroidal oral contraceptives (o.c.) and the development of prolactin-producing adenomas. Sixty-seven patients were admitted for investigation because of menstrual bleeding disturbances and three patients because of galactorrhea. Forty-three patients (61%) had used o.c. Thirty-six out of forty-three women (83%) experienced their menstrual disturbances and/or galactorrhea when using o.c. or immediately after discontinuing the pill. Patients who had used o.c. had shorter duration of symptoms, lower S-prolactin levels and less pronounced enlargement of the sella turcica. These tendencies indicate that o.c. lead to an earlier manifestation of clinically latent prolactin-producing tumours. With or without previous o.c., the patients showed a low total fertility rate, indicating a notably long, clinically undiagnosed period of disease. The accumulated usage of o.c. by the women with prolactinomas was not higher than among the total female population of the same age in Sweden. Furthermore, patients on o.c. for several years did not show a more advanced form of the disease than women who had not taken the pill. Thus, the present study provides no support for the hypothesis that o.c. promote the growth of prolactin-producing pituitary adenomas.

Adenoma↗
PubMed1983

The PHI (PHI-27)/corticotropin-releasing factor/enkephalin immunoreactive hypothalamic neuron: possible morphological basis for integrated control of prolactin, corticotropin, and growth hormone secretion.

By using the indirect immunofluorescence technique, one and the same neuron in the parvocellular part of the paraventricular nucleus has been shown to stain with antisera against three different peptides: PHI (PHI-27), corticotropin-releasing factor (CRF), and enkephalin. This could explain the well-known parallel increase in plasma prolactin, corticotropin, and growth hormone levels--for example, under certain types of stress--as being due to a concomitant release of PHI-like, CRF-like, and enkephalin-like peptides from the same nerve endings in the median eminence. A hypothetical mechanism for the co-ordinated release of these three anterior pituitary hormones is discussed.

Adrenocorticotropic Hormone↗
PubMed1983

Effect of the peptide PHI-27 on prolactin release in vitro.

The present study demonstrates that PHI, a peptide belonging to the glucagon-secretin group and thus structurally similar to VIP, can release prolactin from dispersed rat anterior pituitary cells and also causes release of prolactin from hemipituitaries. PHI-like immunoreactivity has previously been demonstrated in a hypothalamic system with nerve endings in the median eminence, and, taken together, these findings suggest that PHI may represent a physiologic prolactin-releasing factor.

Animals↗
PubMed1982

Subunit 1 of cytochrome oxidase from Neurospora crassa: nucleotide sequence of the coding gene and partial amino acid sequence of the protein.

A partial protein sequence (223 residues) of cytochrome oxidase subunit 1 from Neurospora crassa has been established. The nucleotide sequence of a cloned mitochondrial DNA segment, including the structural gene coding for the mature subunit 1 (CO I locus) was determined. In contrast to the situation in yeast, the CO I locus in N. crassa is not interrupted by long intervening sequences. A polypeptide of 555 residues with a mol. wt. of 61 000 has been deduced from the reading frame established by protein sequencing. With the exception of the C-terminal part of the polypeptide, the proposed sequences for subunit 1 of N. crassa, yeast, and man are largely homologous. Protein sequencing reveals that a region of low homology close to the C-terminal portion belongs to the structural gene in N. crassa. The DNA sequence coding for the prepiece , which characterizes the polypeptide precursor of the N. crassa subunit 1, has not yet been localized. A RNA species of approximately 6.8 kb has been identified as the CO I transcript. There is no indication of splicing of this large transcript.

Amino Acid Sequence↗
PubMed1982

Reoperation for primary hyperparathyroidism.

The reasons for failure of the initial exploration and the results of reoperation were analyzed in 53 patients with a diagnosis of primary hyperparathyroidism, 29 of whom were referred after initial operations elsewhere. Seventy-nine reoperations were performed. Sternotomy was used in 15 patients, and in retrospect was necessary in only 5. There was no operative mortality. The reasons for initial failure were incorrect diagnosis in 6 patients, true recurrence in 4 and persistent disease in 43. Persistence was caused by surgical failure in two thirds and pathology failure in one third. Of 47 patients reoperated on for hyperparathyroidism, 39 (83 percent) were cured, a rate warranting this type of surgery. Analysis of a long-term series of initial operations demonstrates a persistence rate of 5 percent (24 of 461) and a recurrence rate of 1 percent (4 of 461) in this disease. The need for reoperation was les than 1 percent over the recent 5 year period.

Female↗
PubMed1982

Immunoreactive calcitonin in maternal milk and serum in relation to prolactin and neurotensin.

Maternal milk four days post partum contained immunoreactive calcitonin in concentrations which were 22-89 times higher than those noted in concomitantly sampled maternal sera. Neurotensin-like immunoreactivity was barely detectable in milk. It is suggested that calcitonin may be a prerequisite for the concentration of calcium ions in milk but there is also possibility that it acts locally on the intestinal mucosa.

Adult↗
PubMed1982

Urinary cyclic AMP corrected for glomerular filtration rate in the differential diagnosis of hypercalcemia.

To evaluate the usefulness of urinary cyclic AMP (U-cAMP) expressed as nmol/100 ml glomerulus filtrate (GF) when discriminating various hypercalcemic states, we studied 99 patients. Patients with primary hyperparathyroidism (PHPT) showed a positive correlation between individual S-calcium levels and U-cAMP, nmol/100 ml GF (females r=0.49, n=40, p less than 0.01 and males r=0.91, n=7 p less than 0.001). There was also a correlation between U-cAMP, nmol/100 ml GF, and the weight of the adenomas (females r=0.36, n=32, p less than 0.05) and males r=0.79, n=6, p less than 0.05). Patients with PHPT and normal renal function excreted more U-cAMP than controls, 6.0 +/- 1.6 versus 4.3 +/- 1.0 nmol/100 ml GF (mean +/- SD). Of 47 patients with PHPT and normal renal function, 29 showed values below the upper normal limit, 6.3 nmol/100 ml GF (mean +/-2 SD), of the control group; the overlap was 62%. When U-cAMP was expressed as mumol/24 hours, the overlap was 40/47 (85%) and, when expressed as mumol/g creatinine, 31/47 (66%). Three patients with sarcoidosis and two with malignancies and hypercalcemia showed excretory values of U-cAMP, nmol/100 ml GF, above the upper normal limit. Patients with acromegaly or prolactinoma showed normal values of U-cAMP, nmol/100 ml GF. The present data indicate that all three types of determinations of urinary cAMP based on 24 hour urine collections are of little value in the differential diagnosis of hypercalcemic states.

Acromegaly↗
PubMed1982

Effects of long-term bromocriptine treatment on catecholamine excretion and on circulatory adaptation to orthostasis and to exercise in patients with hyperprolactinemia.

Sympatho-adrenally regulated mechanisms of the circulatory system have been studied in seven patients with hyperprolactinemia in order to evaluate the effects of long-term (1-3 months) treatment with bromocriptine. Before treatment catecholamine excretion was within the normal range. Blood volume was low and there was a marked heart rate reaction to orthostasis. ECG showed no abnormalities. Blood pressure and ECG reaction during exercise were normal. The blood pressure heart rate response to handgrip was less marked than in healthy young men. During bromocriptine treatment, serum prolactin levels normalized in all but one patient. Total catecholamine excretion was lowered. Body weight diminished. Resting heart rate and blood pressure fell significantly. Blood volume per kg body weight remained unchanged as did the orthostatic heart rate increase. The circulatory response to handgrip was less marked than before therapy. It seems that long-term bromocriptine therapy provokes a cardiovascular pattern reflecting an inhibition of sympatho-adrenal activity.

Adenoma↗