bluuebunny/crossref_metadata_2025 huggingface dataset:
Impairment of 11β-hydroxylase but not 21-hydroxylase in adrenal 'incidentalomas'
Authors: Reincke Martin , Peter Michael , Sippell Wolfgang G , Allolio Bruno
Published: December 2008

Recent reports have shown an exaggerated response of 17-hydroxyprogesterone in up to 70% of patients with incidentally detected adrenal adenomas ('incidentalomas'). This has been explained by pre-existing 21-hydroxylase deficiency which may be a pathogenetic factor in the development of adrenal tumours. However, other defects in steroidogenesis, such as mild 11β-hydroxylase deficiency, could also result in increased 17-hydroxyprogesterone secretion. We therefore studied the glucocorticoid and mineralocorticoid pathways in patients with adrenal 'incidentalomas' by measuring multiple adrenal steroids before and after 1–24 ACTH stimulation. Twenty patients with adrenal 'incidentalomas' (14 females, 6 males) and 27 healthy controls (14 females, 13 males) were studied. All subjects underwent a 1–24 ACTH stimulation test (250 μg i.v.) with determination of progesterone, 11-deoxycorticosterone, corticosterone, 17-hydroxyprogesterone, 11-deoxycortisol and cortisol at O and 60 min. All steroids were measured by RIA after extraction and HPLC. Patients with 'incidentalomas' had higher stimulated concentrations of 17-hydroxyprogesterone (21·6 ± 8·4 vs 4·2 ± 0·3 nmol/l; P ≤ 0·001), 11-deoxycortisol (8·1 ± 1·2 vs 3·6 ± 0·3 nmol/l; P ≤ 0·001), progesterone (8·28 ± 2·82 vs 1·08 ± 0·15 nmol/l; P ≤ 0·001), and 11-deoxycorticosterone (2·1 ± 0·39 vs 0·78 ± 0·12 nmol/l; P = 0·002) compared with controls. In contrast, cortisol and corticosterone concentrations were not different. There was evidence for impairment of 11β-hydroxylase activity by an increased 11-deoxycortisol/cortisol ratio (0·012 ± 0·003 vs 0·005 ± 0·001 in controls; P = 0·002) and 11-deoxycorticosterone/corticosterone ratio (0·04 ± 0·003 vs 0·015 ± 0·003; P = 0·003). The conclusions reached were that patients with adrenal 'incidentalomas' have increased responses of precursors of the mineralocorticoid and glucocorticoid pathway including 17-hydroxyprogesterone after stimulation with ACTH. This seems to be caused by impairment of 11β-hydroxylase activity rather than by impaired 21-hydroxylase activity in these tumours.

European Journal of Endocrinology 136 196–200
Effect of a high-fat diet on energy balance and thermic effect of food in hypothyroid rats
Authors: Iossa Susanna , Mollica Maria Pina , Lionetti Lillà , Barletta Antonio , Liverini Giovanna
Published: December 2008

We have carried out measurements of energy balance in hypothyroid rats fed a low-fat or a high-fat diet for eighteen days. We have also measured cephalic and processing thermic effect of food (TEF) after a low-fat or a high-fat meal.

Body lipid gain, carcass lipid content and gross efficiency were significantly (P < 0·05) higher in hypothyroid rats fed a high-fat diet compared with hypothyroid rats fed a low-fat diet, while metabolizable energy intake and energy expenditure remained unchanged. Cephalic TEF after a low-fat meal was significantly (P < 005) lower in hypothyroid rats fed a high-fat diet compared with hypothyroid rats fed a low-fat diet, while it was significantly (P <0·05) higher after a high-fat meal than after a low-fat meal in hypothyroid rats fed a high-fat diet. No significant variation was found in processing TEF after a low-fat or a high-fat meal.

Our results indicate that hypothyroid rats are unable to develop increased energy expenditure and increased TEF in response to a high-fat diet.

European Journal of Endocrinology 136 309–315
Effects of selenium and iodine deficiency on thyroid hormone concentrations in the central nervous system of the rat
Authors: Campos-Barros Angel , Meinhold Harald , Walzog Barbara , Behne Dietrich
Published: December 2008

Objective: The effects of single and combined nutritional selenium and iodine deficiency on intracellular thyroid hormone concentrations and type II 5′-iodothyronine deiodinase (5′D-II) activity were examined in different regions of the adult rat brain.

Design: Four groups (n=6) of weanling female Wistar rats proceeding from a breeding line fed a selenium-deficient or a selenium-replete diet for 3 generations, were fed selenium-deficient, iodine-deficient, combined selenium- and iodine-deficient or selenium- and iodine-replete diets for 2 months before they were killed.

Methods: Tissue thyroxine (T4) and tri-iodothyronine (T3) concentrations were determined by highly sensitive RIAs after extraction of the iodothyronines from the tissue samples. The measurement of 5′D-II was based on the release of radioiodide from the 125I-labelled substrate.

Results: Selenium deficiency significantly decreased tissue T3 concentrations in the hippocampus, hypothalamus and striatum to 70–80% of controls, whereas no significant changes were found in the cerebellum, cerebral cortex and brain stem. Tissue T4 concentrations were only marginally affected with the exception of a 35% increase in the cerebral cortex. Iodine deficiency dramatically diminished serum T4 levels as well as intracellular T4 concentrations in all regions examined up to 10–30% of control. In spite of a threefold enhancement of 5′D-II, the iodine-deficient animals still had a significant reduction of tissue T3 concentrations (50–65% of controls) in all regions excepting the cerebellum. The combination of selenium and iodine deficiency did not significantly alter this pattern of changes.

Conclusions: These findings suggest that prolonged selenium deficiency as well as iodine deficiency may compromise thyroid hormone homeostasis in the adult brain leading to tissue hypothyroidism and therefore to impaired brain function.

European Journal of Endocrinology 136 316–323
Effects of 5,5′-diphenylhydantoin on the metabolic pathway of thyroid hormone in rats
Authors: Schröder-van der Elst Janny P , van der Heide Daan , DiStefano Joe J , van der Bent Chris , Kaptein Ellen , Visser Theo J
Published: December 2008

Treatment of rats with phenytoin (DPH), an anti-epileptic drug, results in lower tissue thyroid hormone (TH) levels and interferes with the metabolic pathway of TH. To test the hypothesis that DPH affects the enterohepatic cycle of TH and, thus, the kinetics of TH turnover, we performed a kinetic experiment (three-compartment analysis) and a steady-state, double-isotope equilibrium experiment in rats treated for 3 weeks with DPH (50 mg/kg body weight per day) and in untreated controls. This included measurements of TH and TH metabolite levels, as well as the activities of enzymes involved in the TH metabolic pathway.

DPH treatment resulted in a decrease in the production of thyroxine (T4) (by 25%) and triiodothyronine (T3) (by 37%), a decrease in the T3 concentration in all three pools, and a redistribution of T4 from the fast to the slow pool. The amount of T4 increased in intestinal contents and feces by 66% and 71% respectively. Expressed as a fraction of daily TH disposal, fecal loss of T4 was enhanced from 10 to 23% and that of T3 from 16 to 21%. An increase in T4 and T3 UDP-glucuronyltransferase activities was observed, suggesting that the increased fecal loss of T4 and T3 is secondary to an increased biliary output of their glucuronides. The reduced secretion of TH and increased fecal clearance during DPH treatment can lead in the long run to depletion of TH stores.

European Journal of Endocrinology 136 324–329
Growth hormone increases and insulin-like growth factor-I decreases circulating lipoprotein(a)
Authors: Laron Z , Wang X L , Klinger B , Silbergeld A , Wilcken D E L
Published: December 2008

Background: elevated serum lipoprotein(a) (Lp(a)) is a strong risk factor for coronary artery disease (CAD). Genetic factors appear to account for the major variance in Lp(a) levels but the contribution hormones make in modulating Lp(a) levels is not yet clear. In the present investigation we determined the effects of human growth hormone (hGH) and insulin-like growth factor-I (IGF-I) on circulating Lp(a).

Methods: four groups of patients were studied. Group a: adults with GH deficiency (n=7) treated with hGH (0·05 U/kg/day, s.c.); group b: girls with Turner syndrome (n=7) treated with hGH (0·1 U/kg/day, s.c.); group c: prepubertal boys with idiopathic short stature (n=6) treated with the GH secretagogue (GHRP) hexarelin (60 μg t.i.d. intranasally); group d: Laron syndrome patients (n=10) treated with IGF-I (100–200 μg/kg/day, s.c.). Following overnight fasting, serum was sampled before the initiation of treatment and during 6–9 months treatment.

Results: serum IGF-I rose significantly in all the subjects in all four groups. In the first three groups in which IGF-I was elevated by exogenous or endogenous GH stimulation, serum Lp(a) increased significantly (119±35%, P<0·01; 126±44%, P<0·05; 102±29% P<0·01 for groups a, b, and c respectively). By contrast, serum Lp(a) levels decreased in group d to whom exogenous IGF-I was administered (–66±5%, P<0·001). The differential effect of endogenous vs exogenous IGF-I on serum Lp(a) paralleled the behaviour of serum insulin. Insulin was significantly increased in all the subjects receiving hGH or GHRP (65·2±31%, P=0·109; 93·7±53%, P=0·062; 3536·8±52·7%, P<0·01 for groups a, b, and c respectively) whereas insulin levels were reduced following exogenous administration of IGF-I (—34·1±9·1%, P<0·01).

Conclusions: we conclude that long-term GH treatment increases and IGF-I decreases circulating levels of Lp(a). These findings may have clinical relevance in view of the increasing use of hGH in children and adults and the role of Lp(a) as a CAD risk factor.

European Journal of Endocrinology 136 377–381
Greater disorderliness of ACTH and cortisol release accompanies pituitary-dependent Cushing's disease
Authors: van den Berg Gerrit , Pincus Steven M , Veldhuis Johannes D , Frölich Marijke , Roelfsema Ferdinand
Published: December 2008

We investigated the episodicity of 24-h ACTH and cortisol secretory profiles in 16 patients with Cushing's disease and 25 healthy matched controls, with a recently introduced scale- and modelindependent regularity statistic, approximate entropy (ApEn). The mean (± s.e.m.) ApEn value for plasma ACTH concentrations in Cushing's disease was 1·3817 ± 0·033, and in controls 0·8394 ± 0·049 (P< 10−10); for plasma cortisol concentrations the values were 1·4575 ± 0·052 and 0·8637 ± 0·020 respectively (P<10−10), implying greater irregularity of release for both hormones in Cushing's subjects. The calculated sensitivity and specificity of ApEn for ACTH profiles were 94% and 100% respectively. For cortisol the sensitivity and specificity were both 100%. ApEn was not correlated with sex, age, or the total 24-h secretion rate of ACTH and cortisol in patients and controls. The increased ApEn in patients with Cushing's disease points to an increased disorderliness of ACTH and cortisol secretion compared with healthy controls. In conjunction with the available literature, we hypothesize more generally that autonomous endocrine tumors may be typified by reduced regularity, orderliness, or synchrony of the time structure of hormone release.

European Journal of Endocrinology 136 394–400
Prostate specific antigen in boys with precocious puberty before and during gonadal suppression by GnRH agonist treatment
Authors: Juul Anders , Müller Jørn , Skakkebæk Niels E
Published: December 2008

In healthy boys, the pituitary–gonadal axis exhibits diurnal variation in early puberty. Serum testosterone levels are higher during the night and low or immeasurable during the day. These fluctuating levels of circulating androgens in early pubertal boys are difficult to monitor. Prostate specific antigen (PSA) is a marker of the androgen-dependent prostatic epithelial cell activity and it is used in the diagnosis and surveillance of adult patients with prostatic cancer. We have measured PSA concentrations in serum from boys with precocious puberty before and during gonadal suppression with GnRH agonists to evaluate the effect of normal and precocious puberty on PSA levels and to study the correlation between testosterone and PSA in boys.

Methods: PSA was measured by an ultrasensitive immunofluorometric assay with a detection limit of 003 μg/l. Testosterone was measured by an RIA with a sensitivity of 0·23 nmol/l, and sex hormone binding globulin was measured by a time-resolved immunofluoresence assay (sensitivity 0·23 nmol/l). Five boys with central precocious puberty (CPP) were studied before and after 12 months of GnRH agonist treatment. Sixty healthy boys (12 in each Tanner stage of puberty) and 37 healthy young males served as controls.

Results: PSA levels were immeasurable in all prepubertal boys, whereas PSA levels increased with increasing stage of pubertal maturation. There was a significant correlation between PSA and testosterone and free androgen indices (r = 0·61 and r = 0·65 respectively, both P< 0001). All 5 boys with CPP had significantly elevated PSA levels which decreased to very low or immeasurable levels after GnRH agonist treatment.

Conclusion: PSA may be a useful marker of testosterone activity in boys with normal or precocious puberty.

European Journal of Endocrinology 136 401–405
Lanreotide in the treatment of patients with thyroid eye disease
Authors: Krassas G E , Kaltsas Th , Dumas A , Pontikides N , Tolis G
Published: December 2008

Octreotide, a potent synthetic somatostatin (SM) analogue, was recently evaluated and found to have a beneficial effect in thyroid eye disease (TED), mostly in those patients with a positive Octreoscan-111. Lanreotide (LRT; Somatuline-Ipsen), a new SM long-acting analogue, is more active than natural SM and shows a much longer duration of action. The aim of the present preliminary study was to evaluate the therapeutic effect of LRT in the treatment of TED. Five patients, three males and two females, mean age 50·6±7·6 s.d. (45–64) years, all with severe symptoms of TED were studied. A similar number of patients, matched for age, sex and severity of ophthalmopathy served as controls. All the patients and controls were investigated with orbital scintigraphy using 111In DTPA-d-Phe1-octreotide (Octreoscan111) and selected on the basis of positive octreoscan. The NOSPECS system, as adapted by Donaldson et al. (Journal of Clinical Endocrinology and Metabolism 1973 37 276–-285) and a disease activity score, as proposed recently by an International Workshop, have been followed in this study in order to evaluate the response to treatment. The five patients who comprised the treatment group received 0·04 g LRT i.m. once every 2 weeks over a period of 3 months, after which the Octreoscan-111 was repeated. The control patients were given an injection of water i.m., also once every 2 weeks for 3 months, after which they were evaluated clinically. No Octreoscan-111 was performed in the controls. All patients and controls were evaluated by the same physician, who was unaware of the type of treatment used. A decrease in the NOSPECS score and the clinical activity score was regarded as a positive response, while no change or an increase in the NOSPECS score along with no clinical improvement was regarded as a-negative response. After 3 months of treatment with LRT, four patients showed a statistically significant improvement in ophthalmopathy in both eyes and one in one eye. Three of the control patients with TED did not show any change, one showed a minor improvement in one eye and no change in the other and one showed deterioration in both eyes. An interesting finding was that orbital Octreoscan-111 activity was absent in all the patients after LRT treatment. In conclusion, these preliminary results show that LRT has a beneficial effect on patients with TED, and that since it has to be given only once every 2 weeks, it is probably superior to any other form of SM treatment. However, as the number of patients was small, further studies are needed to confirm our results.

European Journal of Endocrinology 136 416–422
Parathyroid hormone-related protein in neonatal and reproductive goats determined by a sensitive time-resolved immunofluorometric assay
Authors: Rong Haiqin , Hydbring Eva , Olsson Kerstin , Burtis William J , Rankin Wayne , Grill Vivian , Bucht Elisabet
Published: December 2008

Objective: High concentrations of parathyroid hormone-related protein (PTHrP) have been found in goat milk but it is not known whether it can enter the circulation of the neonate. In this study we have developed a sensitive two-site lanthanide immunofluorometric assay (IFMA) using dissociation and enhancement time-resolved fluorometry to address this question.

Method: Affinity-purified anti-PTHrP 38–67 raised in rabbit was biotinylated and immobilized in streptavidin-coated microtitration wells as a 'capture' antibody. As a signal, affinity-purified anti-PTHrP 1–34, raised in sheep, was labeled with an europium chelate. A sensitivity of 0·3 pmol/l was achieved. PTHrP levels were determined in the plasma of eleven neonatal, seven parturient and six non-pregnant, non-lactating goats as well as in goat milk.

Results: The circulating PTHrP levels (mean±s.d.) were significantly increased at day 1 (6·1± 1·7 pmol/l; P< 0·01) and day 3 (3·5±0·6 pmol/l; P< 0·05) after birth in the male kids (n = 8) bottle-fed with milk from the dams, compared with before (2·2±0·7 pmol/l)and 30 min after (2·0±0·6 pmol/l) the first feeding and 14 days (2·4±0·8 pmol/l) later. In the female kids (n = 3) fed with formula there was no such increase and the concentrations remained between 1·6–1·9 pmol/l. In the parturient goats the mean±s.d. PTHrP levels before, during and after parturition were 2·9±1·7. 4·2±2·4 and 3·7±2·2 pmol/l respectively (n = 7) which demonstrated that plasma PTHrP was higher during and after parturition in comparison with before (P < 0·05). The levels in non-pregnant, non-lactating goats were 3·3±1·5 pmol/l (n = 6). PTHrP levels in goat milk were in the nanomolar range and were highest in the colostrum.

Conclusions: A significant increase of plasma PTHrP was observed in goat kids fed with milk from their dams and this increase was not found in kids fed with formula. Plasma PTHrP was also increased during parturition.

European Journal of Endocrinology 136 546–551
Reversible increase of intraocular pressure in subclinical hypothyroid patients
Authors: Centanni M , Cesareo R , Verallo O , Brinelli M , Canettieri G , Viceconti N , Andreoli M
Published: December 2008

Objective: The aim of the study was to analyse the relationship between the ocular parameters, namely intraocular pressure (IOP), and the early forms of subclinical hypothyroidism.

Design: Fifty-three subjects (9 male and 44 female) aged from 18 to 45 years (mean 32±7 years) were selected for this study. Twenty-nine met the criteria of subclinical hypothyroidism and 24 euthyroid subjects, age- and sex-matched, were used as controls.

Methods: All individuals underwent a complete ocular examination, including visual field examination and serial measurement of IOP by means of a Goldmann tonometer. A tonographic examination was also performed.

Results: The hypothyroid patients showed a substantially higher pressure in both eyes compared with control subjects (right eye=17·52±4·74 vs 13·42±1·95 mmHg, p<0.0001; left eye=17·55±3·99 vs 13·71±1·55 mmHg, p<0.0001). Indeed, the tonometric pressure exceeded 18 mmHg in 11 out of the 29 (38%) patients in the right eye and in 8 out of 29 (27%) patients in the left eye. The outflow index was normal in all subjects except in two hypothyroid patients. After two months of L-thyroxine (L-T4) replacement therapy, only one patient continued to show tonometric values above 18 mmHg and the hypothyroid patients showed a significant reduction in mean IOP in both eyes compared with pretreatment values (right eye=14·96± 1·32 mmHg. p<0.0097; left eye=15·03± 1·38 mmHg, p<0.0018). Treatment did not lead to any change in the outflow indices; however, the C value (outflow coefficient at the sclerocorneal corner) returned to normal in the two patients with increased pre-treatment tonographic values.

Conclusions: These findings indicate that the intraocular pressure is increased even in subclinical hypothyroid patients and that, at this early stage, the impairment is fully reversible with L-T4 therapy.

European Journal of Endocrinology 136 595–598
Analysis of human thyrotropin receptor gene expression and immunoreactivity in human orbital tissue
Authors: Spitzweg Christine , Joba Werner , Hunt Nicholas , Heufelder Armin E
Published: December 2008

The human thyrotropin receptor (hTSHR) represents an autoantigen that plays a central role in the hyperthyroidism of Graves' disease (GD). hTSHR transcripts have recently been detected by reverse transcription (RT)-PCR in various extrathyroidal tissues, suggesting that the hTSHR may be more widely distributed than previously thought, and that it may serve as a common antigen in the thyroidal and extrathyroidal manifestations of GD. Using techniques other than RT-PCR, we examined whether RNA encoding hTSHR and hTSHR-specific immunoreactivity can be detected and localized in cultured orbital fibroblasts (OF), orbital connective tissue, extraocular muscle and various extraorbital tissues derived from both patients with Graves' ophthalmopathy (GO) and normal individuals. Using in situ hybridization with a digoxigenin-labeled antisense oligonucleotide probe specific for the extra-cellular domain of hTSHR, specific perinuclear and cytoplasmic hTSHR gene expression was detected in OF of patients with GO and, to a lesser degree, normal individuals. Using a highly sensitive immunostaining technique and a panel of monoclonal and polyclonal antibodies directed against different epitopes of recombinant hTSHR, distinct cytoplasmic hTSHR-like immunoreactivity was detected in methanol-fixed OF and orbital connective tissue, which was absent in abdominal fibroblasts, or when using isotype-matched non-immune immunoglobulins. Mouse monoclonal and pig polyclonal hTSHR antibodies detected cytoplasmic hTSHR-like immunoreactivity in perimysial fibroblasts within extraocular muscle, but not in extraocular muscle fibers. Immunocytochemical staining with rabbit polyclonal hTSHR antibody revealed, in addition, distinct cell surface-associated immunoreactivity in paraformaldehyde-fixed OF, but not in abdominal fibroblasts. Taken together, our results suggest that RNA encoding hTSHR is present and actively processed to immunoreactive hTSHR-like protein in OF residing within orbital connective tissue and extraocular muscle. These data support the concept that OF expressing intact or variant hTSHR may act as extrathyroidal targets for sensitized T-cells and immunoglobulins in GD.

European Journal of Endocrinology 136 599–607
Healing Rate of Swim Bladders in Rainbow Trout
Authors: Bellgraph Brian J. , Brown Richard S. , Stephenson John R. , Welch Abigail E. , Deters Katherine A. , Carlson Thomas J.
Published: December 2008

Swim bladders of juvenile rainbow trout Oncorhynchus mykiss were ruptured and subsequently observed for 28 d to identify healing patterns of swim bladder wounds and the effect of swim bladder rupture on direct mortality. Healing began within 7 d, wounds were completely closed after 14 d, and no mortality occurred. The healing process followed a pattern in which tissue first thickened around the opening (7‐14 d), scarring of the ruptured area occurred, and evidence of the wound ultimately disappeared (21‐28 d). The healing observed in juvenile rainbow trout suggests that swim bladder rupture does not result in direct mortality as was hypothesized; however, the indirect effects of swim bladder injury (e.g., a decreased ability to swim efficiently) may lead to mortality by predation or other natural phenomena that were not observable in this study.
Improvement of an Esocid Bioenergetics Model for Juvenile Fish
Authors: Schoenebeck Casey W. , Chipps Steven R. , Brown Michael L.
Published: December 2008

Feeding rate and water temperature are known to influence the accuracy of fish bioenergetics models. In an effort to improve the accuracy of a juvenile esocid bioenergetics model, we used a regression‐based approach to develop a corrective equation that accounted for the prediction error associated with variable feeding rates and water temperatures. The regression model explained 58% of the variability in the consumption rate prediction error for age‐0 tiger muskellunge (northern pike Esox lucius × muskellunge E. masquinongy) and included the following variables: Initial body weight (g), water temperature (°C), and relative growth rate (cal·g−1·d−1). The corrected model accurately predicted observed food consumption and had lower prediction error (mean error = 7%) than the uncorrected model (mean error = 43%). Moreover, the differences between the observed and modeled estimates of cumulative food consumption were significantly greater than zero for the uncorrected model while those between the observed and adjusted model estimates of food consumption were not, indicating that the corrective equation provided a significant improvement in model accuracy. We recommend using the corrective equation to adjust consumption estimates for juvenile tiger muskellunge when using the esocid bioenergetics model. Further work is needed to identify the physiological mechanisms responsible for consumption‐dependent error in fish bioenergetics models.
Longitudinal Gradients along a Reservoir Cascade
Authors: Miranda L. E. , Habrat M. D. , Miyazono S.
Published: December 2008

Reservoirs have traditionally been regarded as spatially independent entities rather than as longitudinal segments of a river system that are connected upstream and downstream to the river and other reservoirs. This view has frustrated advancement in reservoir science by impeding adequate organization of available information and by hindering interchanges with allied disciplines that often consider impounded rivers at the basin scale. We analyzed reservoir morphology, water quality, and fish assemblage data collected in 24 reservoirs of the Tennessee River; we wanted to describe longitudinal changes occurring at the scale of the entire reservoir series (i.e., cascade) and to test the hypothesis that fish communities and environmental factors display predictable gradients like those recognized for unimpounded rivers. We used a data set collected over a 7‐year period; over 3 million fish representing 94 species were included in the data set. Characteristics such as reservoir mean depth, relative size of the limnetic zone, water retention time, oxygen stratification, thermal stratification, substrate size, and water level fluctuations increased in upstream reservoirs. Conversely, reservoir area, extent of riverine and littoral zones, access to floodplains and associated wetlands, habitat diversity, and nutrient and sediment inputs increased in downstream reservoirs. Upstream reservoirs included few, largely lacustrine, ubiquitous fish taxa that were characteristic of the lentic upper reaches of the basin. Fish species richness increased in a downstream direction from 12 to 67 species/reservoir as riverine species became more common. Considering impoundments at a basin scale by viewing them as sections in a river or links in a chain may generate insight that is not always available when the impoundments are viewed as isolated entities. Basin‐scale variables are rarely controllable but constrain the expression of processes at smaller scales and can facilitate the organization of reservoir management efforts.
Effect of Trawling and Habitat on Mercury Concentration in Juvenile Red Snapper from the Northern Gulf of Mexico
Authors: Wells R. J. David , Chumchal Matthew M. , Cowan James H.
Published: December 2008

We evaluated mercury (Hg) contamination in juvenile red snapper Lutjanus campechanus (<250 mm total length) as an indicator of Hg pollution on the northern Gulf of Mexico (GOM) continental shelf. Specifically, we examined the effects of fish size, commercial shrimp trawling, and habitat type on total Hg concentrations and stable nitrogen isotope ratios (δ15N; a proxy for trophic position) in red snapper. Red snapper Hg concentrations and δ15N values were positively and significantly correlated with fish size. In addition, red snapper collected over trawled habitats had significantly higher Hg concentrations and δ15N values than did red snapper collected from similar, nontrawled habitats. Red snapper also exhibited habitat‐specific differences in Hg concentrations and δ15N values, but differences were size dependent and generally small. Our study suggests that the Hg concentrations of juvenile red snapper in the northern GOM are elevated in areas where commercial shrimp trawling occurs, possibly due to increases in both red snapper trophic position and bioavailable Hg in trawled areas. Additional studies are needed to determine whether Hg concentrations are elevated in fish from trawled areas in other marine ecosystems.
Interferência do tipo de má oclusão nas medidas dos movimentos mandibulares: um estudo realizado com o apoio do exército brasileiro
Authors: Metzger Andrea Luiza Taumaturgo , Campiotto Alcione Ramos , Muzy Paulo Cavalcante
Published: December 2008

OBJETIVO: correlacionar os diferentes tipos de má oclusões dentais com as medidas de lateralidade e protrusão mandibular e amplitude de abertura bucal de indivíduos adultos normais. MÉTODOS: neste estudo participaram 127 militares do sexo masculino que serviam no 21º Depósito de Suprimento do Exército Brasileiro em São Paulo, no ano de 2005, com idades entre 18 e 32 anos. Do total de militares, 47 (39,16%) foram excluídos. Desse modo, a amostra final foi de 80 indivíduos os quais foram divididos em grupo controle (31 - 38,75%) e grupo experimental (49 - 61,25%). Na avaliação, foi realizada uma breve anamnese e inspeção oral, com posterior medição dos movimentos mandibulares de abertura bucal, protrusão e lateralidade para direita e para esquerda. RESULTADOS: 69,38% de indivíduos portadores da má oclusão Classe I de Angle; 16,32% de Classe II-1; 6,12% de Classe II-2; 8,16% de Classe III. A medida de abertura de boca, relacionada com os tipos de má oclusão, não foi estatisticamente significante, apesar de terem sido obtidas as maiores medidas nos indivíduos portadores de Classe III. Já nas medidas de protrusão e lateralidade mandibular existiu uma diferença estatisticamente significante nos grupos de uma maneira em geral. 40,42% dos indivíduos apresentavam ausência de algum dente molar. CONCLUSãO: não houve relação entre a medida de abertura de boca com a presença de má oclusões. Entretanto, houve relação entre as medidas de protrusão e de lateralidade mandibular para a direita e para a esquerda com má oclusões.
O dizer de fonoaudiólogos sobre a evolução terapêutica de crianças com distúrbios fonológicos/fonéticos
Authors: Ramos Ana Paula , Reginato Renata , Deuschle Vanessa Panda
Published: December 2008

OBJETIVOS: investigar fatores que contribuem de forma decisiva na evolução terapêutica nos casos de distúrbios fonológico/fonético, bem como quais abordagens são utilizadas pelos fonoaudiólogos para tratar tais distúrbios. MÉTODOS: dezoito fonoaudiólogos que atendem tal distúrbio foram entrevistados sobre questões relativas à evolução e métodos terapêuticos. RESULTADOS: demonstram um grupo de profissionais provenientes de distintas instituições com predomínio do uso de abordagens fonológicas, embora citem a problemática emocional como um aspecto que dificulta a evolução terapêutica. Afirmam não terem formação para lidar com tal aspecto, mas não a buscam em supervisões ou cursos de formação. CONCLUSÕES: a dificuldade mais mencionada foi a resistência da criança a aceitar o trabalho instrumental de fala, sendo esta encarada como de origem emocional, sendo esse aspecto um dos referidos como deficitários na formação profissional. Abordagens fonéticas e fonológicas foram as mais citadas pelos profissionais.
Efeito de supressão nas vias auditivas: um estudo com os potenciais de média e longa latência
Authors: Simões Mariana Buncana , Souza Renata Rezende de , Schochat Eliane
Published: December 2008

OBJETIVO: avaliar o efeito de supressão no Potencial Evocado Auditivo de Média e Longa Latência em indivíduos sem alterações auditivas, com presença de emissões otoacústicas (EOA) transientes em ambas as orelhas. MÉTODOS: foram avaliados 25 indivíduos (50 orelhas) de 18 a 30 anos de idade, de ambos os sexos, utilizando-se os Potenciais Evocados Auditivos de Média e Longa latência sem e com ruído branco contralateral. Os sujeitos não apresentavam queixa relacionada ao Processamento Auditivo. Foram verificados e comparados os valores numéricos das latências e amplitudes das ondas na avaliação convencional sem ruído e com ruído contralateral. RESULTADOS: a média aritmética da amplitude de resposta na situação com ruído (mascaramento) reduziu em todas as posições (C3/A1, C4/A1, C3/A2 e C4/A2), porém estes achados foram estatisticamente significantes nas posições C4/A1, C3/A2 e C4/A2. CONCLUSÃO: a diminuição da amplitude pode ter relação com o número de sinapses realizadas. O efeito de supressão na amplitude pode estar relacionado à ação do sistema eferente que suprime o número de sinapses neuronais.
The effect of gross cystic disease fluid proteins on oestrogen synthesis in breast cancer cells
Authors: Duncan L J , Robinson G V , Ghilchik M W , Reed M J
Published: December 2008

Gross cystic breast disease frequently occurs in premenopausal women and women with apocrine cysts may have an increased risk of developing breast cancer. Many steroids, growth factors, cytokines and proteins have now been identified in breast cyst fluid (BCF), but it is not yet known whether any of these factors may be associated with an increased risk for cancer, or if these factors have a functional role within the breast. In this study we show that concentrations of the cytokine interleukin-2 are higher in BCF with a low electrolyte ratio, whereas albumin concentrations are increased in BCF with a high Na+/K+ ratio. As albumin has been shown to potentiate the ability of growth factors, such as insulin-like growth factor-I (IGF-I), to stimulate oestradiol-17β hydroxysteroid dehydrogenase (E2DH) (reductive) activity in breast cancer cells, we have examined the ability of other proteins which are found in breast secretions (α-lactalbumin, lactoferrin) or BCF (gross cystic disease proteins-15 and -24) to potentiate the action of this growth factor. While lactoferrin had no effect on E2DH, the other proteins tested significantly potentiated the effect of IGF-I on the activity of this enzyme. Recombinant human albumin also acted synergistically with IGF-I to stimulate E2DH activity, suggesting that the ability of albumin to potentiate growth factor action is an intrinsic property of the molecule itself, rather than being due to the presence of a ligand which is bound to the molecule. Results from these investigations suggest that proteins found in breast secretions and BCF may have a functional role in regulating oestrogen synthesis in breast tissues.
Can patients with benign breast disease who are at high risk for breast cancer be identified using bombesin estimation?
Authors: Milewicz A , Daroszewski J , Jedrzejak J , Bielanski W , Jedrzejuk D , Arkonska A
Published: December 2008

Clinical follow-up studies of women with breast cystic disease indicate an increased risk of subsequent development of breast cancer, but the absolute risk marker has not yet been identified. It has been shown that bombesin/gastrin-releasing peptide can stimulate the proliferation of breast cancer cells in culture. In order to address the question of whether biological measurements might identify women with benign breast disease (BBD) at particular risk for breast cancer, analyses of bombesin and dehydroepiandrosterone sulfate (DHEAS) levels in tumor tissue from patients with breast cancer and BBD were carried out.

The groups of patients comprised 13 women with breast cancer (mean age 52.3 years), 12 women with fibroadenoma (mean age 47.5 years), 6 with microcystic breast disease (mean age 43.5 years) and 6 with gross cystic breast disease (mean age 47.2 years). Malignant and benign tumor tissues were collected after mastectomy or tumorectomy. Bombesin and DHEA-S levels was measured by RIA after homogenization and extraction of tissues. Bombesin concentrations were higher in women with breast cancer (83.67±21.07 ng/g) than in other groups, except women with gross cystic disease (79.6±10.9 ng/g). In contrast, tissue concentrations of DHEAS in women with breast cancer (130.5±34.5 μg/g) were lower with comparison to the others, except women with fibroadenoma (177.7±84.9 μg/g). Bombesin and DHEAS tissue concentrations showed significant negative correlation only in women with fibroadenoma. All values are means±S.D.

The significantly higher bombesin levels in tissues from women with breast cancer and in breast benign gross cystic disease (high risk of cancer) suggests the possible role of bombesin in the malignant process. Further studies are necessary to confirm these initial results.
Morphological and immunohistochemical study of typical and atypical carcinoids of the lung with clinico-pathological correlation
Authors: Klemen H , Smolle-Jüttner F M , Popper H H
Published: December 2008

Typical and atypical carcinoids are neuroendocrine epithelial lung tumours which are difficult to distinguish. Confusion has been introduced by designating atypical carcinoids as well differentiated neuroendocrine carcinomas and including some tumours which are large cell neuroendocrine carcinomas.

We therefore investigated 32 typical and 23 atypical carcinoids of the lung, and 9 combined forms of atypical carcinoid and small cell carcinoma. The following parameters were each independently correlated in a multivariate analysis with 10-year survival data: nuclear and nucleolar polymorphism, mitotic counts, vascular invasion, lymph node metastasis, structural pattern, location of the tumours, immunohistochemistry, age and sex of the patients.

Typical carcinoids were characterized by an absence of vascular invasion and lymph node metastases, and a mean mitotic rate of 0.75/10 high power fields (HPFs), while atypical carcinoids were characterized by vascular invasion and/or metastases, a mean mitotic rate of 4.25/10 HPFs and nuclear pleomorphism. Combined forms of atypical carcinoid and small cell carcinoma were characterized by vascular invasion, metastases and a mean mitotic rate of 20.7/10 HPFs. Vascular invasion, lymph node metastases, mitotic counts and nuclear pleomorphism significantly correlated with 10-year survival data, whereas location, size and structural pattern of the tumour, age and sex did not correlate with survival. All tumours were positive for cytokeratins and at least two out of three general neuroendocrine markers. However, positive reactivity for different peptides, hormones, and neurotransmitters did not correlate with one of the structural subtypes of carcinoid or with patient survival.
Structural analysis of the 5′-flanking sequence of the mouse epidermal growth factor gene
Authors: Pascall J. C. , Brown K. D.
Published: December 2008

The 5′-flanking sequence of the mouse epidermal growth factor gene has been isolated from a mouse genomic DNA library. S1 nuclease mapping indicated that the transcription start sites used in the submaxillary gland and the kidney are identical. Computer-aided sequence comparisons have indicated regions of the gene which may be involved in hormonal regulation.
Heat-shock treatment of mouse pancreatic islets results in a partial loss of islet cells but no remaining functional impairment among the surviving β cells
Authors: Welsh M. , Eizirik D. L. , Strandell E.
Published: December 2008

To elucidate the role of thermal stress on the function of pancreatic β cells, isolated mouse pancreatic islets were incubated for 30 min at 42°C. This resulted in decreased glucose-stimulated insulin secretion, inhibited total protein and pro-insulin synthesis and the induction of heat-shock proteins with molecular weights of 64 and 88 kDa. Six days later, the islets exposed to heat shock showed a lower DNA content, indicating islet cell death. However, the insulin secretory response and rates of oxygen consumption in the presence of glucose were normal. It is suggested that the induction of heat-shock proteins does not permanently impair β-cell function, but rather protects these cells from lasting damage.
Presence of pro-vasopressin mRNA, neurophysin and arginine vasopressin in mouse anterior pituitary cells and the AtT-20 corticotrophic tumour cell line
Authors: Loh Y. P. , Castro M. G. , Zeng F.-J. , Patel-Vaidya U.
Published: December 2008

Pro-vasopressin mRNA, neurophysin and arginine vasopressin (AVP) were assayed in the mouse anterior pituitary gland, in mouse anterior pituitary cells in culture and in the AtT-20 corticotrophic tumour cell line. Northern blot analysis revealed the presence of an ∼700 base pair pro-vasopressin mRNA in anterior pituitary and AtT-20 cells. Neurophysin, identified by immunoblots, and AVP, identified by high-performance liquid chromatography and cross-reactivity with AVP antiserum, were detected in anterior pituitary cells and AtT-20 cells. Immunocytochemical staining with anti-neurophysin showed that ∼40–45% of the dissociated anterior pituitary cells in culture and >95% of the AtT-20 cells were stained. Anterior pituitary cells in culture and AtT-20 cells had a basal level of release of AVP in the 0·01–0·1 nm range. These results indicate that anterior pituitary cells and AtT-20 cells have the ability to synthesize and process pro-vasopressin to AVP and neurophysin, endogenously.
Gonadal regulation of pituitary hormone mRNA levels in male rats
Authors: Abbot S. D. , Docherty K. , Clayton R. N.
Published: December 2008

The control of anterior pituitary hormone gene expression by testosterone in male rat pituitaries in vivo was investigated using dot-blot mRNA-cDNA hybridization assays.

Common α subunit mRNA levels doubled by 2 days after orchidectomy and rose progressively to reach plateau levels three to four times intact control values by 2 weeks. LH-β mRNA increased significantly (≃50%) within 12h, and thereafter progressively to seven times intact control values by 3 weeks after orchidectomy. The changes in α mRNA were likely to have occurred in gonadotrophs and not thyrotrophs, since TSH-β mRNA levels were unaltered by orchidectomy. LH subunit mRNA changes were accompanied by an initial (1–4 days) decrease in pituitary LH content; thereafter, pituitary LH increased in parallel with and by a similar magnitude to the LH-β mRNA. Serum LH rises occurred before significant increases in LH subunit mRNA after orchidectomy. The lack of temporal correlation between mRNA levels and serum and pituitary LH in the early stages after removal of testosterone feedback contrasts with the good correlation when a new steady state was achieved after 3–4 weeks, and indicates differing kinetics for changes in these aspects of gonadotroph function.

An inhibitory effect of testosterone on LH subunit gene expression was confirmed by prevention of the rise in α and LH-β mRNAs when treatment commenced immediately after castration. However, pituitary LH content and serum LH levels were reduced relative to control values, suggesting additional inhibitory actions of testosterone on translational and post-translational events in gonadotrophs. A stimulatory effect of testosterone on α mRNA levels was observed between 4 and 24 h after a single injection in rats castrated 2 weeks previously, no effect being seen on LH-β mRNA. The mechanism for this action remains to be elucidated. Gene specificity of testosterone action was confirmed by unaltered levels of mRNA for prolactin, GH, TSH-β subunit and actin under all experimental conditions. No changes in pituitary content of prolactin or GH were found. We conclude that regulation of LH subunit gene expression by testosterone is an important step in control of gonadotrophin synthesis and availability for release.
Functional expression of the oxytocin receptor in Xenopus laevis oocytes primed with mRNA from bovine endometrium
Authors: Morley S. D. , Meyerhof W. , Schwarz J. , Richter D.
Published: December 2008

Synthesis of the uterine receptor for the hypothalamic hormone oxytocin has been induced in oocytes from Xenopus laevis previously primed with bovine endometrium mRNA. The injected oocytes responded to oxytocin by showing dose-dependent oscillations in membrane currents as recorded by the voltage-clamp method. The response was specific in that it was not elicited by several other peptides tested. The oxytocin-induced membrane changes were suppressed when oocytes were pretreated with an oxytocin receptor antagonist.
Sheep antiluteolytic interferon: cDNA sequence and analysis of mRNA levels
Authors: Stewart H.J. , McCann S.H.E. , Northrop A.J. , Lamming G.E. , Flint A.P.F.
Published: December 2008

A cloned cDNA has been isolated by probing a sheep blastocyst cDNA library using a synthetic oligonucleotide representing the N-terminal amino acid sequence of the antiluteolytic protein, ovine trophoblast protein-1. Sequence analysis of the cDNA confirms the 70% homology between the antiluteolysin and the interferon-α family of proteins; however, the sequence reported here differs at several points from previously reported amino acid and cDNA sequences for the antiluteolysin. In-vitro translation of day-16 poly(A)+ RNA indicated that antiluteolysin mRNA is a major constituent of total mRNA at this stage of blastocyst development, and Northern blotting confirmed that antiluteolysin mRNA production occurred between days 13 and 22 after oestrus. This is consistent with the stage at which embryonic extracts are antiluteolytic on administration in vivo. These and other data confirm that the ovine trophoblast antiluteolysin is an interferon, and suggest that at least five isoforms of this protein may exist.
Characterization of the receptor for glucagon-like peptide-1(7–36)amide on plasma membranes from rat insulinoma-derived cells by covalent cross-linking
Authors: Göke R. , Cole T. , Conlon J. M.
Published: December 2008

125I-Labelled glucagon-like peptide-1(7–36)amide was cross-linked to a specific binding protein in plasma membranes prepared from RINm5F rat insulinoma-derived cells using disuccinimidyl suberate. Consistent with the presence of a single class of binding site on the surface of intact cells, only a single radiolabelled band at Mr 63 000 was identified by SDS-PAGE after solubilization of the ligand—binding protein complex. The band was not observed when 10 nm glucagon-like peptide-1(7–36)amide was included in the binding assay, but 1 μm concentrations of glucagon-like peptide1(1–36)amide, glucagon-like peptide-2 and glucagon did not decrease the intensity of labelling. No change in the mobility of the band was observed under reducing conditions, suggesting that the binding protein in the receptor is not attached to other subunits via disulphide bonds. In control incubations using plasma membranes from pig intestinal epithelial cells, which do not contain specific binding sites for glucagon-like peptide-1(7–36)amide, no cross-linked ligand-binding protein complex was observed.
Immunochemical analysis of the human chorionic gonadotrophin-like material secreted by 'normal' and neoplastic urothelial cells
Authors: Iles R. K. , Chard T.
Published: December 2008

Material with the immunochemical characteristics of human chorionic gonadotrophin (hCG) is produced by bladder tumour cells in vitro and in vivo. In order to characterize this material further, media were collected from 17 cell cultures (three choriocarcinomas, seven bladder carcinomas and seven 'normal' urothelium). The hCG-like material was compared with pregnancy hCG and purified α- and β-subunits by specific radioimmunoassays. Media were also submitted to affinity chromatography and the fractions further analysed by SDS-PAGE and Western blotting. It was shown that both the neoplastic and normal urothelium produced only free β-subunit-like material. This urothelial 'β-hCG' has the same molecular weight and electrophoretic mobility as that present in the intact hCG of pregnancy.