bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age- and sex-associated modification of plasma melatonin concentrations in man. Relationship to pathology, malignant or not, and autopsy findings
Authors: Touitou Y. , Fevre-Montange M. , Proust J. , Klinger E. , Nakache J. P. 
Published: December 2008

Abstract. Plasma melatonin concentrations were determined in 757 unselected elderly patients aged 80.9 ± 9.7 years. The daytime (8–9.30 h) plasma levels of melatonin were in the so-called normal range in only one third of the population whereas 65% of the subjects had abnormal levels of the hormone, most often decreased i.e. less than 0.17 nmol/l (53%) and sometimes increased i.e. 0.43 nmol/l or higher (12%).
A control group of healthy elderly subjects showed the same distribution as the entire population. A sex-difference with significantly higher levels of plasma melatonin in elderly women was observed. With respect to pathology and autopsy findings high levels of the hormone correlated with cancer, chronic renal failure, cardiovascular disease, biological inflammatory syndrome and diabetes. Low levels correlated with neurologic disease, tobacco or alcohol addiction. However, some of these relations were found to be sex-related as they were observed in women but not in men. Our data indicate that pineal function seems to be often altered in elderly human subjects and suggest potential diagnostic applications of melatonin determination.
Changes of molecular forms of growth hormone in bromocriptine treated acromegaly in relation to changes of somatomedin-C and clinical response
Authors: Nortier J. W. R. , Croughs R. J. M. , Donker G. H. , thijssen J. H. H. , Schwarz F. 
Published: December 2008

Abstract. Eleven patients with active acromegaly were treated with 10–20 mg bromocriptine daily for a period of 6–9 months. The clinical response was evaluated by a 'clinical and metabolic improvement score'. The biochemical response was evaluated by measurement of both the mean plasma growth hormone (GH) level during the day and the somatomedin-C (Sm-C) concentration.
Before and at the end of the treatment period plasma samples were fractionated by Sephadex G-100 chromatography in order to study the effects of chronic bromocriptine treatment on the concentrations of total GH and its different molecular forms.
The main observations may be summarized as follows:
Three immunoreactive components were observed on Sephadex chromatography corresponding to molecular weight above 100 000 (big-big GH), 40000–60000 (big GH) and 20000–22000 (little GH). Bromocriptine treatment induced preferentially a reduction of little GH. There was a very good correlation between the decrease of little GH and total GH, and both were significantly correlated with the clinical response. The correlation between the decrease of Sm-C values and that of little and total GH as well as between the decrease of Sm-C and the clinical response was poor.
It is concluded that a) measurement of little GH is not superior to the determination of total GH in the assessment of disease activity of bromocriptine treated acromegalic patients; b) both methods are superior to the measurement of plasma Sm-C levels; c) clinical response out of proportion ot the fall of total GH which can be explained by a preferential reduction of little GH, has not been observed in our investigations.
Long-term culture of differentiated human thyroid tissue
Authors: Mothersill Carmel , Seymour Colin , Moriarty M.J. , Cullen M.J. 
Published: December 2008

Abstract. Human thyroid cells obtained during surgery have been maintained in monolayer culture for at least 2 months and without loss of morphological or functional differentiation. Samples as small as 0.5 g could be cultured but best results were obtained with samples of 5–10 g. The technique used was developed in this laboratory for sheep tissue and was applicable without significant modification to human tissue. It depends on the complete absence of media changes at any time during the culture period. Energy substrates are replenished by the addition of concentrated glucose solutions to the existing media at carefully monitored intervals.
Differences in both morphology and function could be observed between cultures derived from patients with different diseases, suggesting that the technique could have predictive value.
The importance of plasma free insulin and counterregulatory hormones for the recovery of blood glucose following hypoglycaemia in Type 1 diabetics
Authors: Madsbad Sten , Hilsted Jannik , Krarup Thure , Sestoft Leif , Christensen Niels Juel , Tronier Bente 
Published: December 2008

Abstract. After induction of hypoglycaemia in 31 Type 1 (insulin-dependent) patients, the 10 patients with the slowest recovery of blood glucose from hypoglycaemia were arbitrarily compared with the 10 patients with the fastest recovery of blood glucose. No differences were found between the two groups regarding response of glucagon to hypoglycaemia, whereas the epinephrine (2-fold), norepinephrine (2.4-fold) and cortisol responses were significantly greater in the group with the slow recovery.
The plasma free insulin concentrations were higher (2-fold) in the group with slow recovery from 30 min after stop of insulin and throughout the study. This may be explained by a 3-fold greater amount of insulin binding antibodies in this group compared to the group with fast recovery from hypoglycaemia. An inverse significant correlation was demonstrated between the rates of recovery and the amounts of insulin binding antibodies in all the patients (P < 0.02).
This implicates that enhanced counterregulatory hormone responses in the group with the slow recovery from hypoglycaemia could not compensate for the hypoglycaemic effect of a concomitant higher plasma free insulin concentration. Insulin binding antibodies, acting as a depot of circulating insulin, may be a risk factor of prolonged hypoglycaemia in Type 1 diabetics.
Testosterone precursors in spermatic venous blood of normal men and varicocele patients
Authors: Andò S. , Giacchetto C. , Colpi G. M. , Beraldi E. , Panno M. L. , Sposato G. 
Published: December 2008

Abstract. In the present study we determined progesterone (p), 17-OH-progesterone (17-OH-P), androstenedione (Δ4), dehydroepiandrosterone (DHEA) and testosterone (T) in spermatic venous blood of 34 varicocele patients and of 13 normal subjects. We also used the DHEA/Δ4 ratio as an index of the Δ5/Δ4 pathway ratio in testosterone biosynthesis.
The mean of T and Δ4 in the spermatic blood of varicocele (V) patients appeared to be significantly lower with respect to that of normal (N) subjects (T:N = 1718.2 ± 202.4 (sem) nmol/l, No. 11; V = 1243.7 ± 97 (sem) nmol/l, No. 34; P < 0.03. Δ4: N = 56.4 ± 5.6 (sem) nmol/l, No. 12; V = 38.1 ± 4 (sem) nmol/l, No. 27, 0.02> P>0.01).
A negative correlation was observed between the individual age of varicocele patients and 17-OH-P (No. 34, y = −30.66x + 1300, r = −0.57, P < 0.01) Δ4 values (No. 27, y = −1.981x + 96.52, r = −0.67, P< 0.01).
When the ratio of T precursors was evaluated, we observed a positive correlation between the P/17-OH-P ratio and age of varicocele (No. 33, y = 0.0065x–0.092, r = 0.45, P < 0.03). The 17-OH-P/Δ4 ratio was greatly increased with respect to that of normal subjects (N = 5.12 ± (sem), No. 12; V= 10.77 ± 1.31 (sem), No. 27; P<0.01).
These data suggest that the reduced T levels in spermatic venous blood of varicocele patients were due firstly to the enzymatic deficiency of 17-20-lyase and secondly to that of 17α-hydroxylase activity as the patients grow relatively older.
The negative correlation between the DHEA/Δ4 ratio and Δ4/T ratio was observed in normal subjects (No. 10, y = −0.00432x + 0.0542, r = −0.67, P < 0.03) as well as in varicocele patients (No. 27, y = −0.00399x + 0.0587, r = −0.48, 0.02 > P > 0.01). This indicates that in the testis of varicocele patients the testosterone remains prevalently supplied by the Δ5 pathway of biosynthesis.
Studies of the human testis. XIX
Authors: Waheed Abdul , Winters Stephen J. , Farrow George M. , Oshima Hiroyuki , Troen Philip 
Published: December 2008

Abstract. Human testosterone-oestradiol-binding globulin (hTeBG) was purified from pregnancy serum by ammonium sulphate precipitation, preparative flatbed electrofocussing, Concanavalin A-Sepharose affinity chromatography, Sephadex G-150 gel filtration, DEAE-Sephadex chromatography and preparative polyacrylamide gel electrophoresis. The yield was 0.3 mg of hTeBG with a specific acitivity of 1.1 nmoles DHT bound per mg. An antiserum to TeBG was raised in rabbits. Anti-hTeBG IgG was separated from rabbit TeBG by DEAE-Affi-Gel-Blue chromatography. Anti-hTeBG was titrated using protein A-Sepharose which quantitatively binds IgG and therefore bound [3H]DHT-hTeBG-anti-TeBG complexes.
The androgen binding components from human testis were separated on Concanavalin A-Sepharose columns into excluded and retained fractions. The antibody bound both testis fractions with titration curves which paralleled that of TeBG, indicating that these androphilic proteins share common immunodeterminants with hTe-BG. The possibility that these testicular proteins are identical in amino acid sequence to TeBG and differ only in carbohydrate content will require further verification. Finally, these results indicate that antibodies to TeBG can be used to study human testicular androgen-binding protein.
Gonadotrophins and ovarian steroids in cattle II. Pulsatile changes of concentrations in the jugular vein throughout pregnancy
Authors: Schallenberger E. , Rampp J. , Walters D. L. 
Published: December 2008

Abstract. Short-term secretion patterns (derived from samples collected from jugular vein cannulae every 20 min for 12 h) of LH, FSH, progesterone, oestradiol-17β, oestrone and prolactin were studied every 30 days during gestation in heifers. LH pulse frequency and amplitude was greater during the early (months 1-3) and end (months 8-9) than during mid-gestation when pulsatile LH secretion was almost abolished. The frequency of pulsatile FSH release, which was already twice as fast than of LH during early pregnancy, did not change throughout the whole gestation period. Mean, basal and maximal progesterone concentrations were highest during the first 3 months of gestation, were slightly reduced during mid-gestation and decreased further during the last 2 months preceding parturition. Pulses of progesterone occurred concomitantly with the parallel LH/FSH as well as the separate FSH pulses. Average oestradiol-17β concentrations during the first months of gestation were slightly higher than during the mid-luteal phase of the cycle and exceeded during mid-gestation concentrations measured at oestrus. Free oestrone could be detected as early as day 60 of pregnancy. Frequency and amplitude of short-term changes of oestrone increased after the 5th month. Discontinuous secretion of oestrone as well as oestradiol-17β was only arbitrarily but never consistently correlated with either each other or with pulsatile gonadotrophin release.
Apart form an occasional coincidence with pulsatile release of other hormones prolactin concentrations seemed to depend rather on the season of the year and time of the day than on the individual pregnancy stage.
It is concluded that pulsatile LH secretion is either abolished or greatly inhibitied during certain gestation periods (mid- and end-pregnancy) due to pronounced changes in hypothalamo-pituitary sensitivity against both ovarian and placental steroids while short-term secretion of FSH is not. Discontinuous release of ovarian progesterone may result out of pulsatile stimulation by FSH (in the presence of very infrequent pulsatile and low basal LH) whereas the discontinuous secretion of the placental steroids oestradiol-17β and oestrone is obviously independent of the short-term changes of both gonadotrophins.
Platelet and adipocyte thermogenesis in hypothyroid patients: a microcalorimetric study
Authors: Valdemarsson Stig , Fagher Birger , Hedner Pavo , Monti Mario , Nilsson-Ehle Peter 
Published: December 2008

Abstract. Direct microcalorimetry was used for measurements of heat production in cell suspensions of platelets and adipocytes, obtained from hypothyroid patients before and after 3 months on full l-thyroxine substitution.
Platelet heat production was significantly lower than normal before treatment and increased in all 10 patients studied; the mean value increased from 51.3 ± 1.6 fW/cell before to 57.1 ± 1.8 fW/cell after therapy (P< 0.001).
Similarily, adipocyte heat production was initially significantly lower than normal and increased during treatment in all 6 patients investigated. The mean value for heat production per adipocyte was 18.8 ± 1.7 pW/cell before and 32.4 ± 2.5 pW/cell after therapy (P < 0.025), which is still below the level recorded in lean healthy subjects. The adipocyte size did not change significantly. The increase in adipocyte heat production was correlated to the increase in S-triiodothyronine levels (r = 0.84, P <0.05).
In hypothyroidism, the total metabolic activity seems to be comparatively more reduced in adipocytes than in platelets. A difference may exist between these cells with regard to recovery of normal metabolic acitivity during treatment for hypothyroidism. Direct microcalorimetry appears to be an adequate method for monitoring net metabolic effects of thyroid hormones in these cells.
Decreased plasma calcitonin response to a calcium clamp in primary hyperparathyroidism
Authors: Tørring O. , Bucht E. , Sjöberg H. E. 
Published: December 2008

Abstract. In order preoperatively to evaluate the calcium induced plasma calcitonin (CT) response in patients with mild primary hyperparathyroidism (PHPT), 7 postmenopausal (PM) females with PHPT and 14 PM healthy subjects underwent a 2 h calcium infusion. The infusions were performed by means of the 'calcium clamp' technique previously described by us in order to obtain an identical calcium stimulus in all subjects. Immunoreactive calcitonin (iCT) was determined by means of a sensitive RIA utilizing rabbit antibodies directed against the carboxy-terminal amino acid sequence of the CT molecule.
All patients with PHPT had normal basal plasma iCT levels: 10 ± 5 pg-eq/ml (mean ± sd) as a group and not different from the control group: 13 ± 5 pg-eq/ml. In the control group significantly increased plasma iCT was seen at 30, 60, 90 and 120 min in contrast to that of the PHPT group where a blunted response was observed.
The results indicate a diminished CT reserve in these patients which may imply an impaired defence against the PTH mediated bone resorption seen in patients with PHPT.
Radioimmunoassay for 21-deoxycortisol: clinical applications
Authors: Gueux B. , Fiet J. , Pham-Huu-Trung M. T. , Villette J. M. , Gourmelen M. , Galons H. , Brerault J. L. , Vexiau P. , Julien R. 
Published: December 2008

Abstract. A radioimmunoassay for 21-deoxycortisol is described. The immunogen, 21-deoxycortisol-3-(O-carboxymethyl) oxime-bovine serum albumin, was prepared, the antisera raised against it were studied and the reliability of the assay was checked. The antiserum selected cross-reacted with 11-deoxycortisol (0.08%), corticosterone (0.25%), cortisol (0.6%) and 17-hydroxyprogesterone (1.6%). 21-deoxycortisol was separated by celite partition chromatography and eluted in the 70/30 (v/v) isooctane/ethyl acetate fraction together with 11-deoxycortisol and corticosterone.
The radioimmunoassay was used to measure 21-deoxycortisol in the plasma of normal subjects and patients with androgen excess. In normal subjects, men (0.19 ng/ml ± 0.08) and women (0.18 ng/ml ± 0.09) had similar basal levels (mean ± sd). One hour after ACTH stimulation, these levels were increased by a factor of 3.5. In 7 patients treated for classical congenital adrenal hyperplasia associated with 21-hydroxylase deficiency, basal values varied between 9.1 and 39.9 ng/ml (measured at 8 a.m.). In 7 untreated women with lateonset congenital adrenal hyperplasia (with 21-hydroxylase deficiency), ACTH-stimulated levels were increased to between 9 and 25.5 ng/ml. In 14 heterozygous carriers of 21-hydroxylase deficiency, diagnosed by HLA genotyping, all ACTH-stimulated levels were well above the highest corresponding levels in normal subjects, whereas 17-hydroxyprogesterone levels remained within the normal range in 9 of the cases.
Characterization of microheterogencity of human thyroglobulin from different thyroid disorders
Authors: Gärtner Roland , Bechtner Günther , Greil Walter , Horn Klaus , Pickardt C. Renate 
Published: December 2008

Abstract. Human thyroglobulin (Tg) was isolated to apparent purity from various thyroid tissue samples obtained after surgery. Iodine and iodothyronine content of Tg was determined. Isoelectric focussing (IEF) was performed on thin layer agarose gels. Tg revealed a microheterogeneity of 6 bands in the range between pH 4.2 and 4.6. The intensity of the single bands depended on the iodothyronine content of Tg. With increasing degree of iodination, the bands with a lower pI (pI 4.35, 4.40) became more prominent, whereas the bands with higher pI (pI 4.55, 4.60) diminished. This typical change in microheterogeneity pattern could be confirmed by kinetic in vitro iodination and consecutive iodothyronine formation of low iodinated Tg (0.05% iodine). After in vitro desialylation, the bands shifted to a higher pH range (pH 4.60 to pH 4.90), but no reduction of the number of bands occurred. Even in desialylated Tg microheterogeneity is still dependent on iodine content. These results suggest, that the microheterogeneity of Tg is influenced, but not caused by different iodine and NANA content. Different polypeptide composition may be responsible for the microheterogeneity of Tg.
In thyroid diseases without disturbance in Tg synthesis (endemic, diffuse and nodular goitre, Graves' disease) variations in relative intensity of single bands could be related to differences in iodine content. In thyroid cyst fluid and cold nodules in addition to low iodinated Tg, further bands were found with pI-values comparable to desialylated Tg.
Studies on the site of origin and molecular form of the extrahypothalamic corticotrophin-releasing factor (CRF) in rats
Authors: Yasuda Naoki , Yasuda Yuko 
Published: December 2008

Abstract. A homologous radioimmunoassay was developed for rat CRF. CRF immunoreactivity was found widely in the extrahypothalamic areas in the rat central nervous system in concentrations 1–3% of that in the median eminence. Large hypothalamic lesions including the paraventricular nucleus and the median eminence did not cause a decrease in the extrahypothalamic CRF concentrations.
CRF of the rat hypothalamus and cerebral cortex both consisted of high and low molecular weight forms. In contrast the posterior pituitary and the spinal cord contained only low molecular weight forms. Upon gel filtration the low molecular weight CRF of the hypothalamus co-eluted with synthetic rat CRF whereas that of the spinal cord was considerably more retarded. The low molecular weight CRF of the posterior pituitary and cerebral cortex was slightly more retarded compared to synthetic rat CRF.
We conclude that CRF in many extrahypothalamic brain areas and the spinal cord does not originate from the hypothalamus and that there is some heterogeneity in the molecular form of the extrahypothalamic CRF.
High muscle lipoprotein lipase activity in thyrotoxic patients
Authors: Lithell H. , Vessby B. , Selinus I. , Dahlberg P. A. 
Published: December 2008

Abstract. Serum lipoprotein metabolism was studied in 7 women before and after treatment for thyrotoxicosis. Of the lipoprotein lipids, the triglyceride concentration in the low density lipoproteins (LDL) (P < 0.01) and the cholesterol concentration in both LDL (P < 0.01) and the high density lipoproteins (HDL) (P < 0.05) increased significantly during treatment. These changes were accompanied by increases in apolipoprotein B (P < 0.01) and A-1 (P < 0.05) concentrations in serum.
Muscle lipoprotein lipase activity (LPLA) was increased in the thyrotoxic state by 46% (P < 0.05) compared with the value after the patients had been rendered euthyroid, but adipose tissue LPLA was only 8% higher (ns) in the former state. The capacity for removal of exogenous fat, as determined by the fractional elimination rate (K2) at an iv fat tolerance test, was 23% higher in the thyrotoxic than in the euthyroid state (ns).
It is suggested that the increase in muscle LPLA in the thyrotoxic state may be due to enhanced sensitivity to catecholamines. This may contribute to the increased capacity for plasma triglyceride turnover in thyrotoxicosis.
DNA and S-phase representation in human growth hormone producing pituitary adenomas
Authors: Hulting A.-L. , Tribukait B. , Bergstrand G. , Werner S. 
Published: December 2008

Abstract. The DNA contents of 33 pituitary adenomas from patients with acromegaly were analysed with flowcytofluorometry. 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. The possibility of unknown factors regulating growth rate, invasiveness and the lack of metastazation in tumours causing acromegaly cannot be excluded.