bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of physiologic and supraphysiologic hyperglycemia on early and late-phase insulin secretion in chronically dialyzed uremic patients
Authors: Schmitz Ole 
Published: December 2008

Abstract.
To test secretory capacity of the beta-cell to a glucose stimulus in uremic patients on chronic dialysis, three hyperglycemic clamps (plasma glucose increments: 1, 4.5 and 11 mmol/l) were performed in 8 uremic and 8 healthy subjects. Early-phase insulin and C-peptide responses (ΔI and ΔC) during the initial 6 min were consistently exaggerated at all three steps in uremic patients compared with controls (ΔI. 16 ± 4 vs 4 ± 2, 41 ± 11 vs 15 ± 4 and 60 ± 12 vs 24 ± 5 mU/l; ΔC. 0.39 ± 0.13 vs 0.07 ± 0.02, 0.40 ± 0.13 vs 0.16 ± 0.02 and 0.73 ± 0.15 vs 0.29 ± 0.04 nmol/l, p < 0.05 in all cases). Similarly, late-phase insulin secretion defined as the insulin increment between 90 and 120 min after initiation of the glucose challenge was enhanced in uremic patients at the two highest glycemic steps (44 ± 10 vs 16 ± 2 and 123 ± 29 vs 44 ± 5 mU/l, both p < 0.01). The raised late-phase insulin response allowed comparable glucose disposal in the two groups (uremic patients: 9.2 ± 1.0 and 15.5 ± 1.6 mg · kg−1 · min−1· Controls: 9.0 ± 1.3 and 19.9 ± 2.4 mg · kg−1 · min−1). The slopes of potentiation, i.e. the slopes of the regression lines expressing the relationship between changes in insulin increments and changes in glucose, were markedly steeper in uremic patients (0.45 ± 0.09 and 0.66 ± 0.20, early and late-phase respectively) than in controls (0.20 ± 0.06 and 0.25 ± 0.03). No relationship between serum insulin responses and electrolytes or PTH was demonstrated. In conclusion, despite several factors which may inhibit the ability of the beta-cell to respond to a glucose stimulus, acute hyperglycemia elicits in insulin-resistant uremic subjects an exaggerated early and late-phase insulin secretion which is able to compensate for insulin resistance, thereby maintaining normal glucose disposal.
Estrogen biosynthesis in human uterine adenomyosis
Authors: Urabe Mamoru , Yamamoto Takara , Kitawaki Jo , Honjo Hideo , Okada Hiroji 
Published: December 2008

Abstract.
Estrogen biosynthesis (aromatase activity) was investigated in human adenomyosis tissue and compared with that of the normal myometrium, endometrium, and endometrial cancer tissues. Homogenates were incubated with [1,2,6,7-3H]androstenedione and NADPH at 37° C for 1 h. After stopping the enzymatic reaction with ethyl acetate, [4-14C]estrone and [4-14C]estradiol-17β were added to the incubated sample. Estrone and estradiol were purified and identified by Bio-Rad AG1-X2 column chromatography, thin-layer chromatography and co-crystallization. Estrogen formed in the incubated sample was calculated from the 3H/14C ratio of the final crystal. The value for estrone formed from androstenedione was 52–132 fmol· h −1 · g−1 wet weight. Aromatase activity in the adenomyosis tissues was higher than that in normal endometrial or myometrial tissues, but lower than that found in myometrial or endometrial tumour tissue. Furthermore, we investigated the effect of danazol, progesterone, and medroxyprogesterone acetate on adenomyosis cells in primary cultures. Aromatase activity in adenomyosis was blocked by danazol, but stimulated by progesterone and MPA. These results indicate that aromatase activity in adenomyosis may contribute to the growth of the ectopic endometrial tissue which occurs in this disease.
Familial acromegaly
Authors: Pestell Richard G. , Alford Frank P. , Best James D. 
Published: December 2008

Abstract.
Five family members over 3 generations had isolated functional pituitary adenomas diagnosed. In four cases acromegaly was diagnosed, and in the fifth galactorrhoea from prolactin excess was the presenting feature. A prominent feature of the affected members tumours were histological finding of either atypical mixed cell or undifferentiated cell type. Given the low incidence of acromegaly and the demonstration of vertical transmission over 3 generations it is suggested this family represents an inherited pituitary syndrome, distinct from Multiple Endocrine Neoplasia (MEN) type 1.
Erratum
Authors: Schleusener H. , Schwander J. , Fischer C. , Holle R. , Holl G. , Badenhoop K. , Hensen J. , Finke R. , Bogner U. , Mayr W. R. , Schernthaner G. , Schatz H. , Pickardt C. R. , Kotulla P. 
Published: December 2008

Abstract.
Graves' disease is an autoimmune disease characterized by a course of remission and relapse. Since the introduction of antithyroid drug treatment, various parameters have been tested for their ability to predict the clinical course of a patient with Graves' disease after drug withdrawal. Nearly all these studies were retrospective and often yielded conflicting results. In a prospective multicentre study with a total of 451 patients, we investigated the significance of a variety of routine laboratory and clinical parameters for predicting a patient's clinical course. Patients who had positive TSH receptor antibodies activity at the end of therapy showed a significantly higher relapse rate than those without (P < 0.001). However, the individual clinical course cannot be predicted exactly (sensitivity 0.49, specificity 0.73, N = 391). The measurement of microsomal (P = 0.99, sensitivity 0.37, specificity 0.63, N = 275) or thyroglobulin antibodies (P = 0.76, sensitivity 0.18, specificity 0.84, N = 304) at the end of antithyroid drug therapy did not show a statistically significant difference in the antibody titre between the patients of the relapse and those of the remission group. Additionally, HLA-DR typing (HLA-DR3: P = 0.37, sensitivity 0.36, specificity 0.58, N = 253) was proven to be unsuitable for predicting a patient's clinical course. Patients with abnormal suppression or an abnormal TRH test at the end of antithyroid drug therapy relapse significantly more often (P< 0.001) than patients with normal suppression or normal TRH test. Patients with a large goitre also have a significantly (P< 0.001) higher relapse rate than those with only a small enlargement. The sensitivity and specificity values of all these parameters, however, were too low to be useful for daily clinical decisions in the treatment of an individual patient. This is also true for the combinations of different parameters. Though the highest sensitivity value (0.94) was found for a combination of the suppression and the TRH test at the end of therapy, the very low specificity value (0.13) for this combination reduced its clinical usefulness.
DNA evaluation in growth hormone producing pituitary adenomas: flow cytometry versus single cell analysis
Authors: Hulting A. L. , Askensten U. , Tribukait B. , Wersäll J. , Auer G. , Grimelius L. , Falkmer S. , Werner S. 
Published: December 2008

Abstract.
DNA patterns were analysed in 26 GH-producing pituitary adenomas by flow cytometry as well as by microspectrophotometry. Twelve tumours (46%) were diploid according to both methods, whereas 5 tumours (19%) showed aneuploid DNA patterns. Nine tumours were classified differently by the two methods: flow cytometry resulted in diploidy in 2 and aneuploidy in 7 patients, whereas microspectrophotometry showed diploidy in 5 tumours, tetraploidy in 3 and aneuploidy in 1. Methodological limitations may explain the discrepancy in the results obtained by the two methods. However, both the flow cytometry and the microspectrophotometry method show the presence of aneuploid DNA patterns in GH-producing pituitary adenomas despite their benign growth characteristics and the clinically benign course of the disease. This comparative study with two methods measuring DNA content, shows that depending on the criteria used for diploidy-aneuploidy, the freqency of aneuploidy will vary. In this material of 26 GH-producing adenomas, 46% were aneuploid according to flow cytometry and 23% according to microspectrophotometric. However, no correlation to tumour size or GH levels was found with either method when patients with aneuploid and diploid tumours were compared. Therefore, no clinial significance can so far be drawn from these results.
Impaired somatostatin response to orally administered glucose in Type II diabetes entails both somatostatin-28 and -14 and is associated with deranged metabolic control
Authors: Gutniak Mark , Grill Valdemar , Roovete Arved , Efendic Suad 
Published: December 2008

Abstract.
We have investigated the effects of hyperglycemia in Type II diabetic patients on the somatostatin response to oral glucose. In these patients hyperglycemia prevailed (11.8 ± 1.4 mmol/l) and was markedly increased to a maximum of 18.9 ±1.0 mmol/l following the ingestion of 75 g of glucose. The rise in blood glucose following glucose ingestion failed to induce a rise in plasma levels of somatostatin-like immunoreactivity. Biostator-regulated insulin infusion normalized fasting levels of blood glucose and reduced the hyperglycemia following glucose ingestion, i.e. blood glucose now rose from 4.6 ± 0.1 to a maximum of 7.3 ±0.8 mmol/l. This moderate rise in blood glucose was accompanied by a significant (p <0.05) rise in somatostatin-like immunoreactivity. Somatostatin-28 and somatostatin-14 were separated using a Sephadex G-50 fine column. Biostator treatment suppressed plasma levels of both peptides during fasting conditions. Treatment was also accompanied by a rise in both peptides during the first hour following glucose ingestion; this rise did not occur in the untreated state. In conclusion: lack of somatostatin response to glucose in non-insulin-dependent diabetes mellitus is associated with deranged metabolic control. Unresponsiveness to glucose entails the secretion of both somatostatin-28 and -14.
Study on clinical and endocrine characteristics of dexamethasone-suppressible hyperaldosteronism compared with those in primary aldosteronism owing to aldosterone-producing adenoma
Authors: Yamakita Noriyoshi , Yasuda Keigo , Noritake Nobuyasu , Mercado-Asis Leilani B. , Murase Hiroshi , Mune Tomoatsu , Morita Hiroyuki , Miura Kiyoshi 
Published: December 2008

Abstract.
The clinical and endocrine characteristics of 12 Japanese patients with dexamethasone-suppressible hyperaldosteronism were compared with those in 49 Japanese patients with primary aldosteronism due to aldosteronoma. The results were as follows: 1. Most of the laboratory data in the two groups were almost the same. 2. The grade of vascular damage in both uncontrolled (3) and well-controlled (9) patients with dexamethasonesuppressible hyperaldosteronism did not correlate with blood pressure response. 3. The responsiveness of plasma aldosterone to exogenous ACTH in 6 patients with dexamethasone-suppressible hyperaldosteronism was not different from that in 9 patients with aldosteronoma. Even in 3 well-controlled patients in the former group, the plasma aldosterone response was as low as in all the 3 patients with small aldosteronomas. 4. In 4 patients with small aldosteronomas, plasma aldosterone was continuously suppressed with daily dexamethasone to the same degree as in dexamethasone-suppressible hyperaldosteronism. 5. The blood pressure, however, did not improve even in the patients with small aldosteronomas. The possible indistinguishable mechanism in dexamethasone-suppressible hyperaldosteronism and primary aldosteronism with small adenomas and the role of unknown hypertensinogenic steroid(s) other than aldosterone in inducing hypertension in dexamethasone-suppressible hyperaldosteronism are discussed.
Changes in plasma renin activity and aldosterone concentration in response to endothelin injection in dogs
Authors: Otsuka Atsuhiro , Mikami Hiroshi , Katahira Katsutoshi , Tsunetoshi Takeshi , Minamitani Kaori , Ogihara Toshio 
Published: December 2008

Abstract.
The effects of endothelin on the renin-aldosterone system were examined by injecting it intravenously at low (40 pmol/kg) and high (400 pmol/kg) doses into pentobarbital-anesthetized dogs. Plasma renin activity and aldosterone concentration together with hemodynamic parameters were measured before and 60 min after endothelin injection. The lower dose of endothelin induced no significant increase in mean blood pressure or total peripheral resistance. It caused a slight decrease of plasma renin activity from 10.3 ± 1.6 to 5.9 ± 1.3 μg · l−1 · h−1 (p <0.1) and a decrease of aldosterone concentration from 364 ± 68 to 231 ± 58 ng/l (p <0.05) with an increase in total peripheral resistance (p <0.05), but it did not cause any clear change in the plasma renin activity or aldosterone concentration. Thus, endothelin increases the blood pressure mainly by vasoconstriction. The finding of a slight decrease in the plasma renin activity after the lower dose of endothelin, together with our previous finding that endothelin inhibits renin release from isolated rat glomeruli, suggests that endothelin inhibits renin release in vivo. With the higher dose of endothelin, stimulation of renin release secondary to renal vasoconstriction might have counteracted the direct inhibitory action of endothelin. The decrease in aldosterone concentration may have been due to the direct inhibitory action of endothelin on aldosterone release or it may be a secondary effect induced by suppression of plasma renin activity.
Effect of hypothyroidism and thyroid hormone treatment of the rat on hepatic Spot 14 and thyroxine binding prealbumin mRNAs
Authors: Franklyn J. A. , King S. , Ahlquist J. A. , Sheppard M. C. 
Published: December 2008

Abstract.
We have examined the influence of hypothyroidism and thyroid hormone replacement on hepatic levels of Spot 14 and thyroxine binding prealbumin mRNAs determined by dot hybridization and by Northern blot hybridization to specific complementary DNA probes. A marked reduction in Spot 14 mRNA was demonstrated in hypothyroidism, compared with the euthyroid state. T3 replacement of hypothyroid rats, using a wide dose range of T3 (1–20 μg) and 6 and 72 h time points, demonstrated no sustained effect at 6 h, but a dose-dependent stimulation of Spot 14 mRNA at 72 h after daily treatment with T3 was commenced. In contrast, no effect of hypothyroidism or T3 replacement on hepatic levels of thyoxine binding prealbumin mRNA was demonstrated, indicating the specificity of thyroid hormone action. T3 treatment of euthyroid rats was also associated with a dose-related stimulation of Spot 14 mRNA levels. The effect of hypothyroidism and T3 treatment of the rat on hepatic Spot 14 mRNA contrasts with divergent regulatory influences of thyroid status in the anterior pituitary and ventricular myocardium demonstrated using identical animal models, indicating the tissue specific influences of thyroid status.
Slow growth but intense hypertrophy of thyrocytes in long-standing Graves' goitres
Authors: Derwahl Michael , Huber Gerold , Studer Hugo 
Published: December 2008

Abstract.
In order to evaluate the relative contribution of true cell replication, in comparison to mere cell hypertrophy, to the notoriously slow growth of toxic Graves' goitres persistently exposed to TSH receptor antibodies and requiring continuous thyrostatic treatment for more than one year, we have determined the fraction of dividing cells in 8 such goitres, using the monoclonal antibody Ki-67. This antibody identifies cells in late Gl-, S-, G2- and M-phase. The fraction of Ki-67 positive cells ranged from 0.1 to 4.1% with a mean of 2.3 ± 1.6. The apparently low absolute number of dividing cells is in full accordance with growth rates observed in multinodular goitres and in benign tumours of thyroidal and non-thyroidal origin. It is compatible with continuous, intense growth stimulation of the gland, particularly since thyrocytes may down-regulate their growth response when exposed to chronic stimulation. The observations account for the the clinical observation that goitres, and in parti ular Graves' goitres, may take years to double their total mass of thyrocytes, whereas cell hyperplasia and functional overactivity (if untreated) continue unabated.
The effect of tamoxifen on the function and lifespan of the corpus luteum and on subsequent ovarian function
Authors: Swahn M. L. , Bygdeman M. , Matlin S. A. , Wu Z. Y. 
Published: December 2008

Abstract.
The aim of the present study was to investigate the effects of tamoxifen on pituitary and luteal function and on the bleeding pattern when administered continuously in the secretory phase. The study included 16 women with regular menstrual cycles followed during one control, one treatment and one follow-up cycle. Each volunteer received 20 mg tamoxifen twice daily from cycle day 18 to menstruation in the treatment cycle. The luteal phase was slightly, but significantly prolonged during treatment, and FSH, progesterone, 17-hydroxyprogesterone, 20α-dihydro progesterone, estrone, estrone sulphate and estradiol significantly elevated in comparison with corresponding data during the control cycle. The results indicate that estrogen may be of some importance for the regulation of the life span of the corpus luteum in the human. The significantly elevated levels of pregnanediol glucuronide and estrone glucuronide during the follow-up cycle are most likely a result of either a direct effect of remaining circulating tamoxifen levels on the ovary, or mediated through the increased release of FSH. If estrogens are of importance for the process of implantation, which has recently been suggested in subhuman primates, also in the human remains unclear. Studies on the effect of anti-estrogens on the endometrium during the secretory phase of the cycle are ongoing.
Testosterone and its binding in hyperthyroid women before and under antithyroid drug therapy
Authors: Loric Sylvain , Duron Françoise , Guéchot Jérôme , Aubert Pierre , Giboudeau Jacqueline 
Published: December 2008

Abstract.
The serum concentrations of the different forms of circulating testosterone, total testosterone, free testosterone and non-sex-hormone binding globulin bound testosterone (albumin bound + free fractions) which is considered as the biovailable hormone, were measured in 15 hyperthyroid women before and after anti-thyroid drug therapy and in 15 age-matched healthy women. Sex-hormone binding globulin and albumin were quantified. Total testosterone was significantly higher in hyperthyroid women before treatment, whereas free testosterone and non sex-hormone binding globulin bound testosterone were significantly decreased. After recovery, all the parameters returned to the normal range. In hyperthyroid patients, the variations in the different fractions of testosterone can be related to the rise of sex-hormone binding globulin. These variations could be explained by the displacement of the equilibrium defined by the binding equation.
Small stature and insulin-like growth factors: prolonged treatment of mini-poodles with recombinant human insulin-like growth factor I
Authors: Guler Hans-Peter , Binz Katharina , Eigenmann Eugen , Jäggi Silvia , Zimmermann Daniel , Zapf Jürgen , Froesch E. Rudolf 
Published: December 2008

Abstract.
The short stature of mini-poodles is associated with low serum levels of IGF-I. Standard poodles are taller and have considerably higher serum levels of IGF-I. Low IGF-I serum levels may be a symptom or the cause of small stature. We, therefore, undertook a study in which serum IGF-I levels of mini-poodles were elevated over a prolonged period of time by a constant infusion of rhIGF-I and the growth rate of the mini-poodles was followed. We infused four mini-poodles from day 91 to day 221 of age with 6 mg/day of recombinant human insulin-like growth factor I (rhIGF-I). Serum levels of IGF-I rose from about 160 to about 500 μg/l. Blood glucose remained within normal limits. Stimulation tests with clonidine and with GHRH revealed suppression of endogenous GH secretion during the IGF-I infusion. Serum levels of IGF-II and of creatinine were lower in the IGF-I-infused animals. Radial length and body weight did not increase to a greater extent in the IGF-I infused dogs than in controls. However, 'adapted body mass index' (aBMI = gram body weight/(mm radial length)2) decreased in each of the IGF-I infused animals, whereas it increased in each of the control dogs (p <0.05). We conclude that long-term infusion of IGF-I does not stimulate growth in young minipoodles, but may change body composition.
Maturational changes in steroidogenic enzyme activities metabolizing testosterone and dihydrotestosterone in two populations of testicular interstitial cells
Authors: Murono Eisuke P. 
Published: December 2008

Abstract.
The present study examined changes in steroidogenic enzyme activities which metabolize testosterone or dihydrotestosterone between days 21–73 of maturation in Band 2 and Band 3 cells isolated by centrifugation of rat testicular interstitial cells on metrizamide density gradients. 5α-reductase and 17β-hydroxysteroid dehydrogenase activities increased progressively in Band 2 and Band 3 cells between days 21–35 of maturation, then both enzyme activities declined to reach low levels in adult Band 2 and Band 3 cells. The significantly higher activities of both enzymes in Band 3, which contains a greater concentration of Leydig cells at each age, suggest their localization in Leydig cells. 5α-androstane-3α- and 3β-hydroxysteroid dehydrogenase activities increased in both Band 2 and Band 3 cells between days 21–50 of maturation and remained elevated; however, dihydrotestosterone was metabolized primarily to 5α-androstane-3α,17β-diol in Band 2 cells, while 5α-androstane-3β,17β-diol was the major metabolite of dihydrotestosterone in Band 3 cells. These studies suggest that testosterone accumulation during sexual maturation can be influenced by changing patterns of 5α-reductase and 17β-hydroxysteroid dehydrogenase activities which metabolize testosterone, and of 5α-androstane-3α- and 3β-hydroxysteroid dehydrogenase activities which metabolize dihydrotestosterone in both Band 2 and Band 3 cells.
Impaired ACTH and β-endorphin response to sauna-induced hyperthermia in heroin addicts
Authors: Vescovi Pier P. , Pedrazzoni Mario , Gerra Gilberto , Pioli Giulio , Maninetti Letizia , Michelini Massimo , Passeri Mario 
Published: December 2008

Abstract.
To evaluate the responses of circulating β-endorphin, met-enkephalin and ACTH to sauna-induced hyperthermia, 8 male heroin addicts recently admitted to a therapeutic community and 8 age-matched normal subjects were examined. Compared with control subjects, heroin addicts showed 1. A decrease of the basal levels of β-endorphin; 2. Absence of the normal increase of β-endorphin and ACTH after sauna; 3. A lower increase in systolic blood pressure. It is concluded that an impairment of the adaptive response to stress may be present in heroin addicts, even after a relatively short drug-free period (14 days).