bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in polyploidization of exocrine pancreas in db/db diabetic and normal mice
Authors: White J. W. , Swartz F. J. 
Published: December 2008

Abstract.
Polyploidy in tele-insular and peri-insular exocrine pancreas of C57BL/KsJ-db/db diabetic mice and normal littermate controls was quantitated, because the diseased state has been shown to produce an increase in the percentage of polyploid islet B-cells. Three diabetic and 3 normal animals were sacrificed at 4.5, 7, 9.5, 12, 14.5, and 17 weeks of age. Semi-automatic nuclear size analysis on Feulgen stained sections separated the nuclei into polyploid classes, with the following results: 1) In both normal and diabetic mice, percentages of polyploid cells in peri-insular and tele-insular regions differed significantly from one another, and from that of the islet B-cells. Per-cent polyploidy was highest in the peri-insular regions, and lowest in the islets. 2) In the tele-insular regions, per cent polyploidy did not differ between normals and diabetics at 4.5 weeks. By 17 weeks, polyploidy in the diabetics was essentially unchanged, while that of the normal animals had risen and become significantly elevated over that of both the 4.5 week normal and the 17 week diabetic animals. 3) In peri-insular regions, per cent polyploidy did not differ significantly between normals and diabetics throughout the period studied.
Effect of age on plasma aldosterone response to exogenous angiotensin II in normotensive subjects
Authors: Takeda Ryoyu , Morimoto Shinpei , Uchida Kenzo , Miyamori Isamu , Hashiba Tetsuji 
Published: December 2008

Abstract.
The plasma aldosterone response to angiotensin II (10 ng/kg/min for 30 min, iv) under conditions of varied sodium intake was studied in 10 young subjects (20 to 35 years), 9 middle-aged (41 to 56 years) and 11 elderly (66 to 73 years) normotensive subjects. Basal plasma renin activity, basal plasma level and urinary excretion of aldosterone were significantly lower in the elderly than in the young and middle-aged groups on both 130 and 25 mEq sodium intakes. When sodium intake was reduced to 25 mEq for 3 days, the weight loss was significantly greater in the elderly than in the young and middle-aged groups. No significant differences in blood pressure and serum electrolytes were found between the three groups. Angiotensin II infusion caused significant increases in the mean blood pressure in all the three groups, but to a greater extent in the elderly group. Plasma aldosterone level and its absolute increment, but not its per cent increment, after angiotensin II infusion were significantly lower in the elderly than in the young and middle-aged groups. In combined young, middleaged and elderly subjects, the absolute plasma aldosterone increment correlated positively with basal plasma aldosterone and plasma renin activity levels on a 25 mEq sodium intake, and with plasma renin response to sodium restriction.
These results suggest that ageing may cause a lesser plasma aldosterone response to angiotensin II with a decrease in basal plasma aldosterone, in parallel with a decrease in plasma renin activity, under condition of low sodium diet.
Biosynthetic and morphological evidence for inhibition of aldosterone production following administration of ACTH to sheep
Authors: McDougal John G. , Butkus Aldona , Coghlan John P. , Denton Derek A. , Müller Jürg , Oddie CatherineJ. , Robinson Peter M. , Scoggins Bruce A. 
Published: December 2008

Abstract.
The effect of ACTH administration for 1—5 days on the morphology and steroidogenic capability of sheep adrenal tissue has been examined. During this period of treatment there was a gradual decline in the in vitro conversion of 3H-labelled precursors to products of solely zona glomerulosa origin (aldosterone and 18-hydroxycorticosterone) while conversion to products of zona fasciculata origin (17-hydroxyprogesterone, 11-deoxycortisol and cortisol) was stimulated throughout. Conversion to DOC, 18-hydroxydeoxycorticosterone and corticosterone (steroids produced by both the zona glomerulosa and the zona fasciculata) declined after initial stimulation.
Within 2—3 days of the commencement of treatment, the zona glomerulosa showed a progressive decrease in cell number associated with disruption of cords and cell separation. Ultrastructurally, it was found that typical zona glomerulosa cells had almost disappeared. The majority of residual cells in this area had a structure intermediate between zona glomerulosa and zona fasciculata cells.
The similarity in time-course of the alterations in both the morphological and biosynthetic characteristics suggests that the decline in aldosterone output caused by ACTH administration to sheep results from the loss of adrenal zona glomerulosa cells, predominantly due to selective cellular degeneration.
Umbilical serum DHAS and total oestriol in relation to gestational age and mode of delivery
Authors: Noguchi Akihiko , Turnipseed Marvin R. , Bentley Karen , Reynolds John W. 
Published: December 2008

Abstract.
The concentrations of mixed umbilical cord serum dehvdroepiandrosterone sulphate (DHAS) and total oestriol, were determined by radioimmunoassay in 301 infants. Of 280 infants born between 36 and 42 weeks of gestation, 260 were born by vaginal delivery and 20 were delivered by Caesarean (C-section). We found that there was a significant elevation of serum total oestriol (P < 0.005) after 35 weeks with no concomitant gestational change of DHAS. Within the vaginal delivery group steroid values were similar among infants born following spontaneous, oxytocin augmented, and oxytocin induced labour. Within the C-section delivery group, steroid values were similar in infants who experienced spontaneous labour and those who did not. However, DHAS level was significantly higher (P < 0.005) in the vaginal delivery group than in the C-section group. We postulate that the higher DHAS levels in the vaginal delivery group are the result of stress during the late first stage of labour or later.
Free and bound androgens in the female guinea pig during gestation and after parturition and in the offsprings during the perinatal period
Authors: Rigaudière N. , Pradier P. , Delost P. 
Published: December 2008

Abstract.
Total amounts of testosterone (T) and dihydrotestosterone (DHT) and their distribution between non-protein-bound (free), albumin-bound and PBG-(progesterone binding globulin)-bound fractions were determined by radioimmunoassay and equilibrium dialysis from plasma samples. The samples were taken from male guinea pigs during the perinatal period and from pregnant females during gestation and after parturition. Plasma proteins of the foetus and newborn animals appeared to have no high binding affinity for androgens. On the other hand albumin having a binding capacity of 56% for testosterone and 75% for DTH irrespective of the total androgen concentration may be considered to be an important low affinity binding protein.
Maternal plasma developed a specific binding activity with the appearance of PBG in early pregnancy. Alterations in the binding capacity of PBG for T or DHT paralleled changes in plasma concentrations of both androgens, the highest values being observed on day 48 of pregnancy, with a prompt return to normal after parturition. Irrespective of the total androgen concentration, it was evident that PBG was capable of maintaining the free T and DHT at low concentrations (about 0.20 and 0.17 ng/10 ml, respectively). Besides the specific binding due to PBG a non-specific binding due to albumin was observed. The competition which exists between these two binding systems for T and DHT was evident when the quantity of bound androgens was expressed as a percentage. Neither the sex, nor the number of the foetuses, nor the interaction between the two, was found to have any significant effect in the maternal androgens, whether total or free hormone was considered.
The effect of clomiphene citrate on pubertal gynaecomastia
Authors: LeRoith D. , Sobel R. , Glick S. M. 
Published: December 2008

Abstract.
Clomiphene citrate 100 mg daily was used to treat 28 boys with pubertal gynaecomastia. Six failed to complete the course and of the remaining, 14 (64%) responded within 6 months of commencement of therapy. LH, FSH, testosterone and oestradiol levels rose during therapy. It is suggested that clomiphene affects gynaecomastia locally as an anti-oestrogen.
Gonadal dysfunction in adult men with congenital adrenal hyperplasia
Authors: Moore G. W. , Lacroix A. , Rabin D. , McKenna T. J. 
Published: December 2008

Abstract.
Two adult males are described with congenital adrenal hyperplasia (21-hydroxylase deficiency). Patient 1 was receiving therapy with cortisone acetate and presented with clinical features of glucocorticoid excess and uncontrolled adrenal androgen activity. It was established that the short-acting steroid which the patient was receiving was cleared so rapidly that endogenous ACTH secretion was not inhibited.
Patient 2 presented with enlarged and painful testes in association with poor compliance with corticosteroid therapy. The histologic picture of the testis was compatible with 'Leydig cell hyperplasia'. However, successful response to dexamethasone therapy suggests that the testes harboured an adrenal rest. These observations highlight the need for careful follow-up and treatment of adult male patients with congenital adrenal hyperplasia.
Long-term effect of glucocorticoid on connective tissue of aorta and skin Morphological and biochemical studies of tissues from rabbits with intact and injured aortas
Authors: Manthorpe R. , Garbarsch C. , Lorenzen I. 
Published: December 2008

Abstract.
The long-term effect of prednisolone — 0.6 mg/day for 63 days — upon mechanically induced inflammation and repair processes in vascular connective tissue was compared with that upon undamaged vascular wall and intact skin of rabbits. The investigations included histological examination of aorta as well as biochemical analyses of collagen and various glycosaminoglycan fractions, RNA, DNA and alpha-amino nitrogen. The metabolism of collagen was estimated by in vitro labelling with [14C]proline and the metabolism of glycosaminoglycans by in vivo labelling with [35S]O4. The radioactivity of [125I]albumin in the aorta and serum was also studied.
The collagen, glycosaminoglycans, RNA, DNA and water of vascular connective tissue during inflammation and repair and of intact skin was found to be more sensitive to the action of prednisolone than the connective tissue of undamaged vascular wall. An increased degradation of newly synthesized collagen was observed in damaged aorta as well as in skin in which also the biosynthesis of collagen was inhibited. Prednisolone inhibited the biosynthesis of glycosaminoglycans and decreased the total amount of glycosaminoglycans and of nucleic acids in the damaged aortas and the skin. The [125I]albumin aorta-to-serum ratio was significantly increased in the damaged aorta. Prednisolone treatment decreased the ratio in injured aortas, but elevated the ratio in the undamaged vessels. Prednisolone inhibited intimal thickening of the injured aortas.
Interrelationships between tumour size, age, plasma growth hormone and incidence of extrasellar extension in acromegalic patients
Authors: Klijn J. G. M. , Lamberts S. W. J. , de Jong F. H. , van Dongen K. J. , Birkenhäger J. C. 
Published: December 2008

Abstract.
In 44 consecutive acromegalic patients we studied the interrelationships between tumour size, age, incidence of extrasellar extension, growth hormone levels and 'tumour growth'. These parameters were compared with results from a previous study in 62 prolactinoma patients. It appeared that the incidence of extrasellar extension in acromegalic patients was lower than in the prolactinoma patients (32 versus 44%). In acromegalic patients extrasellar extension occurred on the average at a lateral sellar and tumour area of almost 1 cm2 larger than in prolactinoma patients (with respect to sellar size generally above 3 cm2 versus 2 cm2, with respect to tumour size generally above 4 cm2 versus 3 cm2).
Log tumour size and log basal growth hormone level were positively correlated (P < 0.0005). In the acromegalic patients there was a negative correlation between the size of the pituitary tumour and the age of the patient (P < 0.005) in contrast to the absence of such a relationship in the prolactinoma patients. In the group of acromegalic patients mean tumour size decreased gradually from the third to the sixth decade (5.0, 3.8, 3.0 and 2.3 cm2, respectively). The interval between the time of appearance of symptoms and the time of diagnosis was significantly shorter in younger patients and in women. The restriction of large tumours (lateral area > 5 cm2) to young patients (< 35 year) and the short period between the appearance of symptoms and the time of diagnosis in these patients indicate that growth hormone secreting pituitary tumours generally grow more rapidly in younger patients.
Insulin secretory reserve in insulin dependent patients at time of diagnosis and the first 180 days of insulin treatment
Authors: Madsbad Sten , Krarup Thure , Regeur Lisbeth , Faber Ole K. , Binder Christian 
Published: December 2008

Abstract.
Eleven newly diagnosed insulin dependent patients were studied before and during the first 16 h after start of insulin treatment. All the patients were found to have significant amounts of C-peptide in plasma indicating residual insulin secretion. The fall in blood glucose after start of insulin therapy was followed by a parallel decrease in C-peptide (R = 0.99, P < 0.01) suggesting that the beta-cells may respond to variation in blood glucose.
Eight of the patients were studied 1, 4, 7, 14, 90 and 180 days after start of insulin therapy. During the first 90 days of treatment an increasing maximal C-peptide concentration was found after a standard breakfast test meal. Two thirds of this improvement i beta-cell function was found after the initial 14 days with an average increase in maximal C-peptide of 260 per cent. The sensitivity to glucose improved.
Urinary excretion of albumin and total protein in normal and streptozotocin diabetic rats
Authors: Rasch R. , Mogensen C. E. 
Published: December 2008

Abstract.
Using a radioimmunoassay the urinary albumin excretion rate has been measured in groups of streptozotocin diabetic female Wistar rats and non-diabetic control rats. Total protein excretion has been measured with the Biuret technieque in the same animals.
One group of 4 rats was given 35 mg streptozotocin iv. The rats remained non-ketotic and were not treated with insulin. The geometric mean albumin excretion before the induction of diabetes was 0.38 mg/24 h. For the next 4 days after streptozotocin the albumin excretion was not significantly increased. From day 16 to day 30 the mean albumin excretion was 2.4 mg/24 h, which is a significant increase from the initial value (2P = 0.0082). Another group of 8 rats showed ketonuria on the second day after the injection of 100 mg streptozotocin iv, and they were treated with insulin daily. Geometric mean albumin excretion before the induction of diabetes was 0.38 mg/24 h, and the next 4 days after the induction of diabetes it was not significantly increased. During the period from day 16 to day 30 a small, but significant, increase to 0.76 mg/24 h (2P = 0.029) occurred when compared to prevalues.
Total protein excretion showed a significant increase in both diabetic groups just after the streptozotocin injection.
In a long-term study albumin excretion was measured every month up to the age of 12 months in 8 insulin treated rats. The results obtained in this group have been compared to that of a non-diabetic control group. Both groups showed a steady increase in albumin excretion. However, the slope of the curves was significantly steeper in the diabetic rats (2P = 0.0000095).
Cyclic AMP phosphodiesterases of the rat ovary. Oestrous cycle dependent activity change of high affinity form
Authors: Schmidtke J. , Meyer H. , Epplen J. T. 
Published: December 2008

Abstract.
In the rat ovary, from prenatal to adult stages, two electrophoretically distinct forms of cyclic AMP phosphodiesterase (E.C.: 3.1.4.17) occur. These forms were analysed for their affinity towards cAMP in both crude and partially purified preparations. Whereas the slow electrophoretic form, which has a low affinity towards cAMP, shows a linear Lineweaver-Burk plot, the fast electromorph exhibits anomalous kinetic behaviour in that cAMP affinity appears to increase with decreasing cAMP-concentration. This form shows dramatic alteration of maximum velocity during the oestrous cycle, attaining maximum activity at metoestrus. This rise of activity is sensitive to inhibition of protein synthesis.
The inability of Angiotensin II infusions to raise plasma vasopressin levels in haemodialysis patients
Authors: Hammer M. , Ølgaard K. , Madsen S. 
Published: December 2008

Abstract.
Since it has previously been claimed that angiotensin II (All) stimulates vasopressin (AVP) secretion, the effect of All-infusions was studied in 1) 6 normals, 2) 5 non-nephrectomized haemodialysis (HD) patients, and 3) 6 nephrectomized HD patients. In dialysis patients the infusion rate was increased step-wise from 2–12 ng AII/kg bw × min−1 and was terminated if diastolic blood pressure (BP) increased more than 20 mmHg. Normals were infused at a constant rate of 4 ng AII/kg bw × min−1.
In all the groups significant increments in BP and plasma aldosterone occurred while plasma renin activity decreased. The plasma vasopressin level was unchanged in normals, while in the two groups of dialysis patients a minor decrease was found. The present study has therefore not been able to confirm a stimulating effect of a physiological dose of All on AVP secretion, and the results in anephric patients indicate that a normal plasma All concentration is of no importance for the plasma AVP level.
The effect in post-menopausal women of natural human and artificial oestrogens on the concentration in serum of prolactin
Authors: Andersen Jesper Rye , Schroeder Erik , Lebech Paul Erik 
Published: December 2008

Abstract.
25 women aged 53–78 years with at least two vears menopause were divided in three groups receiving one of the following oral treatments for three weeks: 2 mg oestradiol-17β plus 1 mg oestriol, 4 mg oestradiol-17β plus 2 mg oestriol or 50 μg ethinyloestradiol daily. Blood samples were collected before, during and after the treatment and the effect on the serum concentration of prolactin, oestradiol-17β, follicle-stimulating hormone and luteinizing hormone was evaluated.
During treatment with natural human oestrogens serum oestradiol-17β levels were significantly higher than before treatment. The serum concentration of prolactin was unchanged in patients receiving 2 mg oestradiol-17β plus 1 mg oestriol but increased in patients receiving 4 mg oestradiol-17β plus 2 mg oestriol or 50 μg ethinyloestradiol, thus indicating dose-dependence for natural human oestrogens. However, the increase was moderate, and these higher levels were not significantly different from levels of prolactin in serum found in 16 younger women. Concentrations of follicle-stimulating hormone and luteinizing hormon were depressed during treatment, the former to significantly lower levels when higher doses of oestrogens were used.
Dynamic study of antidiuretic hormone during benign mineralocorticoid and metacorticoid hypertension
Authors: Marchetti Jeannine , Thibonnier Marc , Gonzales M. Françoise , Corvol Pierre , Menard Joël 
Published: December 2008

Abstract.
Deoxycorticosterone-treated rats with benign hypertension were observed for changes in antidiuretic hormone (ADH) excretion during the mineralocorticoid hypertension phase (weeks 4–8 after DOC implantation) and the metacorticoid phase (weeks 16–18 after DOC). During the latter period, blood pressure was still high but electrolytic abnormalities due to excess DOC had disappeared. Urinary ADH excretion was studied in rats with normal sodium intake (Group I) and in rats which drank a 1% NaCl solution (Group II) under three conditions: basal conditions, after water loading and after hypertonic sodium loading. The rise in blood pressure (BP) was larger, lasted longer and was more frequently accompanied by malignant hypertension in Group II than in Group I animals. During the mineralocorticoid hypertension, a 2- and 3-fold increase in urinary ADH excretion occurred in all DOC-treated rats, concomittantly with a rise in plasma osmolality. ADH excretion did not change in control rats drinking sodium chloride solution. In hyper- and normotensive animals, oral water loading reduced ADH excretion and hypertonic saline loading increased it. However, under both these conditions, ADH excretion remained higher in hypertensive than normotensive rats. During metacorticoid hypertension, BP was normal in Group I rats, but remained elevated in Group II rats. In both groups, electrolyte abnormalities disappeared and urinary AVP excretion returned to normal under basal conditions and after suppression and stimulation tests.
The present results show that increased ADH excretion is characteristic of DOC-induced benign hypertension even in the absence of sodium from drinking water. There are two possible mechanisms through which ADH might raise BP: 1) by expanding plasma volume, and 2) by acting as a vasoconstrictor agent directly affecting the arterial walls. However, vasopressin does not seem necessary to maintain hypertension, since ADH excretion was normal during the metacorticoid phase.
Plasma and pituitary gonadotrophins before and after LRH in normal, cryptorchid and castrated rats
Authors: Grizard Geneviève , André Max , Boucher Daniel 
Published: December 2008

Abstract.
Rats were either castrated or made cryptorchid at 1, 8, 21 or 49 days of age. Sham-operated animals were used as controls. At 70 days, all the animals were anaesthetized and then injected with saline or 100 ng of LRH (time 0). Blood samples were collected before and after the injection (time – 15, 0, 8, 15, 45 min), and the animals were killed by decapitation. Plasma LH and FSH were measured by radioimmunoassays (RIA) and pituitary gonadotrophins were measured by bioassays and RIA.
Irrespective of the age of surgery, plasma gonadotrophin levels of cryptorchid rats were elevated: they were nearly tripled for LH and doubled for FSH but they always remained distinctly below those of castrated rats. The LH response to LRH injection was higher in cryptorchid rats than in controls, but this response was lower than in castrated rats. Plasma FSH response to LRH injection depended on the age of surgery and FSH levels were not always significantly increased.
In rats operated on at 49 days, following cryptorchidism, or castration, pituitary gonadotrophin content was increased. The highest value was found in castrated rats. After LRH injection pituitary LH content was unchanged in controls but decreased in other animals, pituitary FSH content was decreased in castrated rats and unchanged in cryptorchid rats.
These results showed, in the adult rat that at any time of operative cryptorchidism between 1 and 49 days of age, a negative feedback control persisted, exerted by the testicular system on the hypothalamo-hypophyseal system as regards the secretion of both LH and FSH.