Search results for "pituitary"
showing 10 items of 238 documents
MR IMAGING AND HORMONAL FINDINGS IN PATIENTS WITH IDIOPATHIC GROWTH HORMONU DEFICIENCY
1993
Until the introduction of MR imaging in neuroradiological diagnostic, diagnosis of the ecotopic posterior pituitary lobe, first described by the pathologist Priesel in 1920, was rare. Recently it has increasingly been diagnosed by MR in patients whose anamnesis showed birth trauma. We performed MR of the hypothalamic-pituitary region in 17 patients with idiopathic growth hormone deficiency. 8 patients had additional deficiencies of the anterior pituitary lobe whereas the function of the posterior lobe of the hypophysis was normal in all patients. Indications of birth trauma were present in only 2 patients. The cause of anterior lobe insufficiency was determined by MR in 8 patients with panh…
The influence of risk factors on the onset and outcome of psychosis: What we learned from the GAP study
2020
The GAP multidisciplinary study carried out in South London, recruited 410 first episode of psychosis patients and 370 controls; the aim was to elucidate the multiple genetic and environmental factors influencing the onset and outcome of psychosis. The study demonstrated the risk increasing effect of adversity in childhood (especially parental loss, abuse, and bullying) on onset of psychosis especially positive symptoms. Adverse life events more proximal to onset, being from an ethnic minority, and cannabis use also played important roles; indeed, one quarter of new cases of psychosis could be attributed to use of high potency cannabis. The “jumping to conclusions” bias appeared to mediate …
CHANGES IN ALBINO RAT TESTICLE INTERSTITIAL CELLS AFTER PITUITARY STIMULATION IN VIVO WITH HeNe LASER
1995
Population I Leydig cells of the central part of the Albino rat testicle showed signs of increased but nonspecific activity in the entire series of experimental animals compared with sham irradiated controls (n = 30 in each group) after anterior pituitary stimulation with low incident energy levels of the HeNe laser at 632.8 nm with an incident power at the pituitary calculated as 2.75 ± 0.25 mW. The authors conclude that LLLT applied to the pituitary in the rat model at the parameters used in the present study may have an effect on testosterone production. Further quantitative and qualitative work is required to assess the significance of the increase in activity of type I Leydig cells and…
The HMGA1 protoncogene frequently deregulated in cancer is a transcriptional target of E2F1
2011
Reactivation of the HMGA1 protoncogene is very frequent in human cancer, but still very little is known on the molecular mechanisms leading to this event. Prompted by the finding of putative E2F binding sites in the human HMGA1 promoter and by the frequent deregulation of the RB/E2F1 pathway in human carcinogenesis, we investigated whether E2F1 might contribute to the regulation of HMGA1 gene expression. Here we report that E2F1 induces HMGA1 by interacting with a 193bp region of the HMGA1 promoter containing an E2F binding site surrounded by three putative Sp1 binding sites. Both gain and loss of function experiments indicate that Sp1 functionally interacts with E2F1 to promote HMGA1 expre…
Estrogen receptor (ER)-mediated transcriptional regulation of the human corticotropin-releasing hormone-binding protein promoter: differential effect…
2004
CRH-binding protein (CRH-BP) regulates activation of the hypothalamic-pituitary-adrenal (HPA) axis by binding and inhibiting CRH. We investigated for the first time transcriptional regulation of the human CRH-BP promoter using transient transfections. Estrogen receptors (ERs) contributed to ligand-independent constitutive activation of the promoter, whereas in the presence of estradiol ERalpha induced and ERbeta repressed promoter activity in a dose-dependent manner. TNFalpha inhibited promoter induction by ERalpha in the absence and presence of estradiol. Three ERE half-sites in the CRH-BP promoter bound ERalpha and ERbeta in an EMSA, and disruption of ERE half-sites by site-directed mutag…
Organizational and activational effects of testosterone in two populations with high androgenization susceptibility = Efectos organizadores y activad…
2013
Los esteroides sexuales como la testosterona (T) producen una organización y/o modificaciones relativamente permanentes de la estructura y función del sistema nervioso central. Una alta exposición prenatal a la T podría estar relacionada con una mayor sensibilidad a los efectos activadores de dicha hormona durante la edad adulta. Por otra parte, las fluctuaciones en los niveles endógenos de T pueden modificar transitoriamente las capacidades socio-cognitivas. Así, la conducta y los procesos cognitivos podrían ser el resultado de la interacción entre los efectos hormonales organizadores y activadores. La T podría ser considerada como un predictor de rasgos masculinizados tales como los rasgo…
Effects of gadolinium and cadmium on the electrically evoked release of 45calcium from the isolated rat neurohypophysis.
1988
Isolated neural lobes of the rat pituitary gland were fixed by their stalks to a platinum wire electrode. They were loaded with 45calcium and then superfused with radioactivity-free Krebs-solution. The efflux of 45calcium into the superfusion medium was determined. After 54–60 min of superfusion the spontaneous outflow of 45calcium was 2.03%/min of the tissue 45calcium. It was not affected by cadmium (Cd2+, 0.03-3 mmol/1), but reduced by 40% in the presence of 1 mmol/1 gadolinium (Gd3). Electrical stimulation with pulses of 15 Hz (3 times for 1 min with intervals of 1 min) evoked a 45calcium release of 14.4% of the tissue radioactivity. The evoked release of 45calcium was reduced by 80% in …
Effects of tetraethylammonium ions on frequency-dependent vasopressin release from the rat neurohypophysis.
1988
1. Isolated rat neurohypophyses were fixed by their stalks to a platinum wire electrode and superfused with oxygenated Krebs-HEPES solution. Vasopressin release into the medium was determined by radioimmunoassay. Vasopressin secretion was increased by electrical stimulation at different frequencies (3-30 Hz) and different train lengths (75-900 pulses). The effects of tetraethylammonium (TEA) ions and of enhanced calcium were tested. 2. Electrical stimulation at 7.5 or 15 Hz evoked a markedly larger release of vasopressin than stimulation at 3 Hz. During continuous stimulation at 7.5 and 15 Hz the evoked vasopressin release per pulse declined rapidly, but with similar time constants for both…
Loneliness Mediates the Relationship Between Early Life Stress and Perceived Stress but not Hypothalamic–Pituitary–Adrenal Axis Functioning
2021
Many authors have proposed that early life stress (ELS) provokes a dysregulation of the hypothalamic–pituitary–adrenal (HPA) axis and contributes negatively to the management of stress in adulthood. However, these associations have not always been observed, making it necessary to include new factors that could explain the different results found. In this regard, people with ELS experiences report less social support during adulthood, suggesting that loneliness could be a mediating factor. Thus, our aims were to investigate whether ELS was related to both perceived stress and diurnal HPA axis activity, and whether loneliness mediates these relationships, in a community sample (N=187, 18–55ye…
Vitamin D Deficiency in Cushing’s Disease: Before and After Its Supplementation
2022
Background: The primary objective of the study was to assess serum 25-hydroxyvitamin D [25(OH)D] values in patients with Cushing’s disease (CD), compared to controls. The secondary objective was to assess the response to a load of 150,000 U of cholecalciferol. Methods: In 50 patients with active CD and 48 controls, we evaluated the anthropometric and biochemical parameters, including insulin sensitivity estimation by the homeostatic model of insulin resistance, Matsuda Index and oral disposition index at baseline and in patients with CD also after 6 weeks of cholecalciferol supplementation. Results: At baseline, patients with CD showed a higher frequency of hypovitaminosis deficiency (p = 0…