bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variations in serum T3, rT3, 3,3'-diiodothyronine and 3',5'-diiodothyronine induced by acute myocardial infarction and propranolol
Authors: Faber Jens , Kirkegaard Carsten , Lumholtz Ib Bo , Siersbæk-Nielsen Kaj , Friis Thorkild 
Published: December 2008

Abstract.
Serum levels of thyroxine, 3,5,3'-triiodothyronine (T3), 3,3',5'-triiodothyronine (rT3), 3,3'-diiodothyronine (3,3'-T2), 3',5'-diiodothyronine (3',5'-T2) and TSH were measured in two clinical situations which are both known to induce a low serum T3 high serum rT3 syndrome: 1) during the early course of acute myocardial infarction (AMI) and after recovery, and 2) before and during one week's propranolol medication (20 mg 4 times a day). In 10 patients with AMI serum levels of the iodothyronines were unchanged on admission to hospital (in average 6.6 h after onset of symptoms). However, already 24 h after onset of symptoms serum T3 and 3,3'T2 were reduced whereas serum rT3 and 3',5'-T2 were increased. Serum T3 and 3,3'-T2 reached a nadir on day 4 and 3, respectively, whereas serum rT3 and 3',5'-T2 reached peak values 24 h after onset of symptoms.
In eight healthy, euthyroid volunteers propranolol medication induced similar changes in iodothyronine concentration as AMI did. However, the alterations were more delayed. Serum T3 decreased slowly reaching statistically significantly reduced values on day 7. Serum rT3 and 3',5'-T2 were significantly enhanced from day 3 and 4, respectively. A close parallelism in alterations of serum T3 and 3,3'-T2 levels was observed.
Our data suggest that T3 in the two situations studied is a major precursor for 3,3'-T2 probably as a consequence of reduced 5'-deiodinase activity. It seems possible that the mechanisms affecting the metabolism of the iodothyronines in AMI and during propranolol medication involved the same enzyme system. However, the late appearance of the alterations in serum iodothyronines levels during propranolol medication might indicate different modes of action.
Effect of receptor occupancy on [3H]dexamethasone binding to circulating leukocytes
Authors: Murakami Tohru , Brandon David D. , Loriaux D. Lynn , Lipsett Mortimer B. 
Published: December 2008

Abstract.
To determine the effect of steroid occupancy of the glucocorticoid receptor on the measurement of total receptor concentration using Scatchard plot of [3H]dexamethasone (Dex) binding to circulating leukocytes, leukocytes were incubated with 10−7m cortisol or 10−9m Dex prior to [3H]Dex binding study. Total binding capacity calculated from Scatchard plot analysis of [3H]Dex binding was not significantly reduced after pre-incubation with cortisol. However, total binding capacity was significantly lower after pre-incubation with Dex. These data suggest that total glucocorticoid receptor concentration can be measured from a 3 h incubation of leukocytes obtained from untreated patients.
Oestrogens, compared to other steroids of testicular origin, in bloodplasma of boars
Authors: Claus R. , Hoffmann B. 
Published: December 2008

Abstract.
Oestrogens, testosterone, and 5α-androstenone ('boar taint steroid') were determined in peripheral and spermatic vein blood plasma of boars. Oestrone was the predominant steroid in both the conjugated and the unconjugated fractions of total oestrogens. Concentrations of conjugated oestrogens in peripheral plasma generally are in the range of several nanograms/ml, which is similar to the range of 5α-androstenone and testosterone. Unconjugated total oestrogens are in the lower nanogram-range. These concentrations, however, are still higher than those during the oestrus in sows. Stimulation with hCG led to increased concentrations of peripheral plasma oestrogens, demonstrating their testicular origin. Comparative measurements in spermatic vein plasma and peripheral plasma show that in general the testis has to secrete different amounts of the individual steroid to maintain the appropriate peripheral level. A highly correlated course of all the steroids measured was apparent.
This was shown for the diurnal rhythm, the age-related changes and for the increase after application of hCG.
Calcium and phosphate metabolism in acromegaly
Authors: Halse Johan , Haugen Harry N. 
Published: December 2008

Abstract.
A study of 28 consecutively admitted patients with active acromegaly revealed the following results with regards to calcium and phosphate metabolism.
When compared with controls, there was an increase in serum calcium levels corrected for total protein, urinary calcium was increased, but the tubular re-absorption of calcium was normal. There was a negative correlation between the urinary cAMP and calcium excretion indicating that hyperabsorption of calcium from the gut is the cause of the increased urinary calcium excretion.
Serum phosphate values were increased in acromegalics and correlated well with TmP/GFR which was also increased.
Immunoreactive parathyroid hormone (PTH) was increased in 5 patients, three of whom had hypercalcaemia. In the remaining patients the PTH values were scattered within the normal range. The urinary cAMP/creatinine ratio was increased in acromegalics, but most of this difference was abolished when urinary cAMP was expressed relative to 100ml of glomerulus filtrate.
It is concluded that parathyroid hyperactivity is a feature of acromegaly.
Clinical and pathological significance of sibling Graves' disease
Authors: Tanaka Toshio , Katayama Shoichi , Kuma Kanji , Tamai Hajime , Matsuzuka Fumio , Hidaka Hiroyoshi 
Published: December 2008

Abstract.
The clinical picture and serum antithyroid antibodies in 16 pairs of siblings with Graves' disease were compared with an age and sex matched group of 32 patients with Graves' disease who did not have a family history of any thyroid disease (control patients). There was a significant difference in frequency and mean titres of antibodies to thyroglobulin between sibling patients. (positive 76.0%) and control patients (positive 40.0%), but not in microsomal antibodies (sibling; positive 92.0%, control; 92.0%). There were no significant differences in the mean values of 24 h 131I-thyroidal uptake, serum T3U, serum T4 and T3 concentrations before treatment between the two groups.
Lymphoid follicles and degeneration of the epithelia were more often found in the thyroid glands of sibling patients than in those of the control patients, when 32 (16 sibling, 16 control) thyroid glands from the same groups in the clinical study, including antibody series, were examined pathologically after subtotal thyroidectomy for Graves' disease. Moreover, there was a strong tendency to increased lymphocyte and plasma cell infiltration in the thyroid glands of sibling patients with Graves' disease.
The findings might indicate that Graves' disease is closely related to Hashimoto's thyroiditis, especially in sibling patients with Graves' disease.
Effects of chronic hypocalcaemia on plasma renin activity in man
Authors: Gedik O. 
Published: December 2008

Abstract.
A study was carried out to investigate the role of serum calcium in the regulation of renin secretion. The subjects for this study comprised of two groups. Group 1 consisted of 10 patients with primary or secondary hypoparathyroidism. Blood samples for basal PRA (plasma renin activity) were drawn at 8 a.m. when the patients were recumbent and on a normal sodium intake. Then all the patients were given a constant diet containing 10 mEq sodium for 4 days and were given 80 mg of Furosemid orally every day. On the morning of the fifth day blood samples were drawn after the patients had been upright for 4 h. These patients were treated with vitamin D2 and when normocalcaemic states were achieved the same study was repeated. Group 2 (control group) consisted of 10 normal, healthy subjects of both sexes. They were prepared for the experiment in the same way as for group 1.
In the hypocalcaemic state mean serum calcium level was 5.6 ± 0.3 mg/100 ml. After treatment with vitamin D2, the mean serum calcium level was increased to 9.6 ± 0.1 mg/100 ml (P < 0.001). There was no significant difference in the mean serum sodium and potassium levels in either hypocalcaemia or normocalcaemia. But the mean stimulated PRA (12.12 ± 1.13 ng/ml/h) was found to be decreased in hypocalcaemia compared to in normocalcaemia and in the control group (22.87 ± 1.18 and 23.83 ± 0.86 ng/ml/h, respectively). The difference of means was significant (P < 0.001). There were no significant differences between basal PRA in hypocalcaemic and normocalcaemic state as well as in the control group. (P> 0.5, P > 0.2 and P> 0.5, respectively).
Our results indicate that serum calcium plays an important role in the regulation of renin secretion.
Stimulation of rat ovarian ornithine decarboxylase in vitro by hCG, amino acids and bovine serum albumin
Authors: Käpyaho Kirsti 
Published: December 2008

Abstract.
Rat ovarian ornithine decarboxylase activity could be stimulated in vitro by a variety of factors, which apparently have different modes of action. Ovarian cells prepared from pre-pubertal rats by collagenase dispersion exhibited a low but detectable ornithine decarboxylase activity after a 6-h incubation in a defined medium. The enzyme activity was markedly enhanced in vitro by hCG, which also produced increased accumulation of cyclic AMP and stimulated the secretion of progesterone. In addition to the gonadotrophin, ovarian ornithine decarboxylase activity was strikingly stimulated by some non-essential amino acids, and especially by bovine serum albumin. While markedly enhancing ornithine decarboxylase activity, none of the latter additions increased the accumulation of cyclic AMP or enhanced the secretion of progesterone.
Bovine serum albumin enhanced powerfully ornithine decarboxylase activity in vitro at very small concentrations (from 0.75 μm). The half-life of the enzyme remained unchanged (26—28 min) upon stimulation indicating that the stimulation mechanism did not involve any stabilization of the enzyme.
Importance of time-related parameters of pre-optic electrical stimulation in the release of LH in the pentobarbital-blocked pro-oestrous rat
Authors: Johnson James H. , Somori Gabriel J. 
Published: December 2008

Abstract.
The effectiveness of pre-optic stimulation in overcoming the pentobarbital blockade of ovulation in the rat has long been recognized and employed in neuroendocrine investigations. Although some reports have appeared comparing certain aspects of electrical stimulation in effectiveness in releasing LH, no complete study in female rats has been reported. The present study utilized regularly cycling rats of the Charles River CD strain in which ovulation was blocked by the injection of sodium pentobarbital on the afternoon of pro-oestrus. Electrical stimulation was delivered through bipolar platinum electrodes stereotaxically positioned in the pre-optic area, and LH was measured in plasma samples obtained at the onset of stimulation and 10, 20, 30, 45, 60, 80, 120 and 150 min thereafter. LH release was established in response to a baseline set of parameters: 15 Hz, 1.5 mA and 1.5 ms per phase, 30 s on/off for 60 min. Stimulations employing equi-coulombic increments of 1/3 introduced in each parameter in turn were compared in groups of 4—6 animals. Use of small increments in each parameter allowed the detection of those parameters to which the pre-optico-hypothalamo-pituitary system is most sensitive over the range studied, namely duration: of each pulse and of the overall stimulation period. This observation may be explained in terms of characteristics of the pituitary responsiveness.
Evaluation of LH, FSH, TSH, Prl, and GH secretion in patients suffering from prostatic neoplasms
Authors: Rolandi Ermanno , Pescatore Domenico , Milesi Giovanni M. , Giberti Claudio , Sannia Antonello , Barreca Tommaso 
Published: December 2008

Abstract.
The concentration of luteinizing hormone (LH), of follicle stimulationg hormone (FSH), of thyroid stimulating hormone (TSH), of prolactin (Prl) and of growth hormone (GH) was evaluated, in basal conditions and during stimulation tests, in serum of 32 patients with benign prostatic hypertrophy (BPH), of 29 patients suffering from prostatic carcinoma and of a control group of similar age. Significant difference in pituitary Prl secretion was found between the prostatic patients and the control group.
'Proopiocortin fragments' in normal human adult pituitary. Distribution and ultrastructural characterization of immunoreactive cells
Authors: Celio Marco R. , Pasi A. , Bürgisser E. , Buetti G. , Höllt V. , Gramsch Ch. 
Published: December 2008

Abstract.
The distribution and ultrastructure of cells immunoreactive towards antisera against synthetic fragments of proopiocortin were studied in human pituitaries by immunohistochemical methods. Anterior lobe cells exhibiting the ultrastructural characteristics of corticolipotropes, as well as all epithelial cells 'invading' the posterior lobe, display β-endorphin/β-lipotropin-ACTH immunoreactivities. At low dilution a β-lipotropin antiserum, raised with highly purified antigen, stains also somatotropes. α-MSH antibodies bind to certain corticolipotropic cells in the pars distalis and to only a few of the cells 'invading' the pars nervosa. Met-enkephalin antisera react only with isolated cells in the anterior lobe. These results indicate a striking difference in the processing of the proopiocortin precursor molecule in different corticolipotropic cells of the human hypophysis. Furthermore, the hypothesis of a homology between cells 'invading' the human neurohypophysis and those of the intermediate lobe of lower vertebrates, is questioned.
Discrepancy between the effects of desialylation of human chorionic gonadotrophin on in vitro ovarian biological activity and on receptor binding
Authors: Brand E. C. , Odink J. , van Hall E. V. 
Published: December 2008

Abstract.
An in vitro bioassay based on progesterone production by enzymatically-dispersed immature rat ovary cells, was used to investigate the effect of sialidase treatment on the biological activity of human chorionic gonadotrophin (hCG). The potency in this bioassay system and in an ovarian receptor assay were compared, to substantiate possible discrepancies between the effect of this treatment on biological activity and on receptor binding.
Ovarian cells responded dose-dependently to the addition of hCG as well as sialidase treated hCG (asialo-hCG). Dose-response curves of hCG and asialo-hCG were parallel and the maximal stimulation levels reached were the same. Sub-maximal doses of hCG and asialo-hCG were additive. The potency of asialo-hCG was 65% of the original preparation. Addition of low concentrations of phosphodiesterase inhibitor resulted in a greatly enhanced sensitivity of the bioassay, but had no effect on the potencies of asialo-hCG and hCG.
In contrast to intact gonadotrophins, the receptor assay potency of asialo-hCG was more than three times the bioassay potency. In agreement with this, it was found that when equal amounts of 125I-labelled hCG and asialohCG were specifically bound to the ovarian cells, the latter stimulated progesterone production less effectively.
It is concluded that there is a discrepancy between the effect of desialylation on the biological activity and on the receptor-binding ability of hCG.
Cell-free synthesis of α and β subunits of human chorionic gonadotrophin with polyribosomes from early placenta
Authors: Maruo Takeshi , Koide S. S. 
Published: December 2008

Abstract.
Polyribosomes were prepared from first trimester human placenta and assayed for protein synthetic activity in the cell-free translatory system derived from wheat germ or from first trimester placental tissue. High incorporation of [3H]proline was observed, whereas incorporation of [3H]glucosamine did not occur. The radiolabelled proteins synthesized by the wheat germ cell-free system were immunoprecipitated with specific antisera for hCG, α- and β-subunit and analyzed by electrophoresis on sodium dodecyl sulphate-polyacrylamide gels. The apparent molecular weight of the immunoprecipitable CG-α-protein was estimated to be 15 000 daltons, while that of the immunoprecipitable β-protein was about 24 000 daltons. Since the molecular weights of the polypeptide part of authentic α and β subunits are 10 200 and 16 000 daltons, respectively, the cell-free products may represent their precursor protein forms; pre-CG-α and pre-CG-β.
The rates of production of hCG, α and β proteins by in vitro incubation of placental polyribosomes with the wheat germ translating system were determined by the respective homologous radioimmunoassays. It is noteworthy that CG-β-protein production was highest during the initial 15 min of incubation and became limited subsequently, whereas an increase in hCG and α-protein formation was observed at 90 min of incubation. The present results suggest that the placental polyribosomes contain mRNA for α- and β-subunits. Earlier accelerated synthesis of CG-β protein might be required for the subsequent association with the newly synthesized α-subunit protein to form hCG.
Mechanisms of action of testosterone propionate on LH and FSH release by the pituitary gland in cyclic female rats
Authors: Roos J. , Plas-Roser S. , Aron Cl. 
Published: December 2008

Abstract.
The aim of this work was to determine whether changes in pituitary responsiveness to LRH could account for the effect of testosterone propionate (TP) on the gonadotrophic function of the pituitary in 4-day cyclic female rats.
Doses of 250, 500 and 1000 ng LRH were injected ip on pro-oestrus at 15.30 h in rats either pre-treated with 5 mg TP on dioestrus II at 10.00 h or injected with 30 mg/kg pentobarbital (PB) at 13.00 h. LH release induced within 30 min by LRH was higher in PB than in TP-treated rats. Even by using 250 ng LRH full ovulation was observed on the morning of oestrus in PB-treated rats. On the other hand, only partial ovulation occurred whatever the dose of LRH used in TP-treated rats; a great number of luteinized follicles was shown to be constantly associated with post-ovulatory corpora lutea. While LRH caused a significant FSH release (30 min later) in TP-treated rats, no FSH release could be shown in PB-treated rats. The pituitary FSH content appeared to be decreased and the pituitary LH content remained unchanged while a sharp increase in both blood FSH and LH concentrations occurred following injection of 1000 ng LRH in TP-treated rats. Concomitantly a sharp decrease in the number of pituitary gonadotrophs (AB-PAS+) was observed. A significant decrease in the number of the small roundshaped PAS positive cells was also observed. The mechanisms whereby TP influences the function of the pituitary-ovarian axis are discussed in the light of these results.
Regulation of serum-progesterone in patients with essential hypertension
Authors: Wambach G. , Koschut M. , Helber A. , Bönner G. , Kaufmann W. 
Published: December 2008

Abstract.
Increased levels of progesterone in serum have been reported in male patients with essential hypertension (EH). We, therefore, investigated serum progesterone levels in relation to excretion of aldosterone after 4 days of low Na+ intake and 6 days following high Na+ diets, in 11 normotensive controls, 22 male patients with EH and 8 male patients with hypertension of renal origin (RH). In the group of normotensive controls, the concentration of progesterone in serum averaged 228 ± 90 and 186 ± 93 (mean ± sd) pg/ml during low and high regimens of Na+ intake, respectively, despite a fall in the excretion of aldosterone from 22.8 ± 9 to 1.8 ± 1.4 μg/24 h. Similarly, in patients with EH, serum progesterone remained unchanged during either low or high Na+ intake regimens: 197 ± 73 and 219 ± 83 pg/ ml, respectively. In patients with RH, serum progesterone tended to be lower during both low and high Na+ diets: 167 ± 61 and 185 ± 72 pg/ml, respectively. In 5 normotensive controls, diurnal variations of progesterone and cortisol were significantly correlated (r = 0. 726, P < 0.005).
The results of the present study suggest, that progesterone is not involved in metabolism of Na+, either in normotensive or hypertensive male subjects. Correlation between circadian variations of progesterone and cortisol suggests, that progesterone levels are modified by ACTH secretion.
Biosynthesis and accumulation of cadaverine and putrescine in rat ovary after administration of human chorionic gonadotrophin
Authors: Andersson Anne-Charlotte , Henningsson Stig 
Published: December 2008

Abstract.
In the ovaries of pre-pubertal rats stimulated by human chorionic gonadotrophin (hCG) the temporal changes in cadaverine and putrescine formation were investigated. In addition, the dose-response relationship of hCG and its effect on the diamine formation and the effect of hCG on the content of diamines and polyamines in the ovaries and the urine were studied. The results show that the ovary stimulated by hCG, in addition to putrescine, forms cadaverine at a highly increased rate. The elevated diamine formation was parallelled by an increased content of cadaverine and putrescine in the ovary.
Treatment with aminoguanidine elevated the content of cadaverine in the ovary, suggesting that diamine oxidase has a role as a regulator of the intra-ovary level of cadaverine.
These results confirm that cadaverine can be synthesized in an inducible manner in mammalian tissues. This is, virtually, the first report of elevated formation of cadaverine in response to an exogenous gonadotrophin.
Sebum production and plasma testosterone levels in man after high-dose medroxyprogesterone acetate treatment and androgen administration
Authors: Novak E. , Hendrix J. W. , Chen T. T. , Seckman C. E. , Royer G. L. , Pochi P. E. 
Published: December 2008

Abstract.
In 47 healthy male volunteers, the administration of 100 mg of oral medroxyprogesterone acetate daily for 42 consecutive days caused a modest 16.7% decrease in sebum production from a baseline mean of 2.28 mg to a post-treatment mean of 1.90 mg. This represented a considerably smaller decrement than had been reported in the literature. Immediately following the period of medroxyprogesterone acetate administration, the addition of daily oral doses of either 50 mg of fluoxymesterone, methyltestosterone, or calusterone to the 100 mg daily dose of medroxyprogesterone acetate for 42 additional days resulted in the return of sebum production to essentially pre-suppression values.
A statistically significant decrease in serum testosterone levels, from a pre-treatment mean of 862 ng/100 ml to a post-treatment mean of 251 ng/100 ml, was seen in all groups treated during the first 42 days with 100 mg of medroxyprogesterone acetate daily (P < 0.05). The addition of 50 mg of fluoxymesterone, methyltestosterone, or calusterone to the 100 mg of medroxyprogesterone acetate for another 42 day period caused a further decrease in serum testosterone levels (P < 0.001); the fluoxymesterone-medroxyprogesterone acetate combination produced the greatest decrease of serum testosterone levels, from a pre-treatment mean value of 932.8 ng/100 ml (Day 1), to a post-treatment mean value of 70.6 ng/100 ml (Day 85).
The daily dose of 20 mg of medroxyprogesterone acetate for 42 consecutive days caused less suppression of serum testosterone levels (from 831 ng/100 ml to a mean of 585 ng/100 ml) than 100 mg of medroxyprogesterone acetate (from 831 ng/100 ml to a mean of 214 ng/100 ml), but more than that of placebo (pre-treatment mean of 886 ng/100 ml to a post-treatment mean of 871 ng/100 ml). Except for changes in haemoglobin, haematocrit and haptoglobin values, no other medically significant changes were seen in the routine screening chemistries and urineanalyses for any of the drug groups. These changes were not unexpected, as they are known to occur with androgen therapy. Of potentially clinical importance was the absence of any effect of antithrombin-3 levels during the study period.
No major side effects were reported other than in one patient who developed gynaecomastia of his right breast on Day 42 of medroxyprogesterone acetate therapy. After his being removed from the study, the gynaecomastia disappeared rapidly.