Search results for "Somatostatin"
showing 10 items of 71 documents
An actin network dispatches ciliary GPCRs into extracellular vesicles to modulate signaling
2017
Signaling receptors dynamically exit cilia upon activation of signaling pathways such as Hedgehog. Here, we find that when activated G protein-coupled receptors (GPCRs) fail to undergo BBSome-mediated retrieval from cilia back into the cell, these GPCRs concentrate into membranous buds at the tips of cilia before release into extracellular vesicles named ectosomes. Unexpectedly, actin and the actin regulators drebrin and myosin 6 mediate ectosome release from the tip of cilia. Mirroring signal-dependent retrieval, signal-dependent ectocytosis is a selective and effective process that removes activated signaling molecules from cilia. Congruently, ectocytosis compensates for BBSome defects as…
The activation of NMDA receptors alters the structural dynamics of the spines of hippocampal interneurons
2017
N-Methyl-d-Aspartate receptors (NMDARs) are present in both pyramidal neurons and interneurons of the hippocampus. These receptors play a key role in the structural plasticity of excitatory neurons, but to date little is known about their influence on the remodeling of interneurons. Among hippocampal interneurons, the somatostatin expressing cells in the CA1 stratum oriens are of special interest because of their functional importance and structural characteristics: they display dendritic spines, which change their density in response to different stimuli. In order to understand the role of NMDAR activation on the structural dynamics of the spines of somatostatin expressing interneurons in …
Hepatic Steatosis Index in Acromegaly: Correlation with Insulin Resistance Regardless of the Disease Control
2018
Objective. In acromegaly, both lipotoxicity secondary to GH excess and insulin resistance have a significant impact on the liver. Ultrasonography has shown poor sensitivity in detecting hepatic steatosis and noninvasive methods have been proposed. We evaluated the hepatic steatosis index (HSI), a validated surrogate index of hepatic steatosis, and we correlated it with disease activity and insulin resistance. Design. Thirty-one patients with newly diagnosed acromegaly were studied at diagnosis and after 12 months of treatment with somatostatin receptor ligands. Methods. Glucose and insulin levels, surrogate estimates of insulin sensitivity, and hepatic steatosis through ultrasonography and …
Insulin sensitivity and secretion and adipokine profile in patients with Cushing’s disease treated with pasireotide
2018
Purpose: To evaluate the effect of pasireotide on β-cell and adipose function in patients with Cushing’s disease (CD). Methods: Clinical and hormonal parameters, insulin secretion evaluated by HOMA-β and by the area under the curve (AUC2h) of C-peptide during a mixed meal tolerance test and insulin sensitivity, evaluated by the euglycaemic hyperinsulinaemic clamp, were evaluated in 12 patients with active CD, before and after 6 and 12 months of pasireotide. In addition, a panel of adipokines including leptin (Ob), leptin/leptin receptor ratio (Ob/Ob-R ratio), adiponectin, resistin, visfatin, adipocyte fatty acid binding protein (AFABP) and non-esterified fatty acids (NEFAs) was evaluated at…
Clinical and metabolic effects of first-line treatment with somatostatin analogues or surgery in acromegaly: a retrospective and comparative study.
2012
To evaluate the metabolic effects of first-line somatostatin analogues or surgery in acromegaly. Retrospective, comparative, 12-month follow-up. Two hundred and thirty one patients (123 men, age 47.32 ± 14.63 years) with active acromegaly, first line treatments were somatostatin analogues in 151 (65.4%) and surgery in 80 (34.6%). Metabolic syndrome (MS) parameters, glucose, insulin and GH during oral glucose tolerance test, stimulated insulin sensitivity by insulin sensitivity index (ISI Matsuda), early and total insulin-secretion rate by insulinogenic index and AUC(INS), visceral adiposity function, expressed by visceral adipose index (VAI). Somatostatin analogues treatment improved all MS…
Somatostatin-receptor scintigraphy in Graves' disease: reproducibility and variance of orbital activity.
2000
Somatostatin-receptor (SSTR) scintigraphy using the single photon emission computed tomography (SPECT) technique allows the assessment of orbital inflammation in patients with Graves' disease. Previous studies showed differences in orbital octreotide uptake already 4 hr after injection. In this study, analysis of inter-/intra-observer variance and reproducibility in the evaluation of orbital SPECT images was performed. First, SPECT data of one representative female patient with clinically active Graves' ophthalmopathy (GO), obtained 4 hr after intravenous injection of 110 MBq 111In-pentetreotide and processed by filtered backprojection, were analyzed. Transverse SPECT images were reconstruc…
Somatostatin-producing neuroendocrine tumors of the duodenum and pancreas: incidence, types, biological behavior, association with inherited syndrome…
2008
Somatostatin-producing neuroendocrine tumors (SOM-NETs) of the duodenum and pancreas appear to be heterogeneous. To determine their clinicopathological profiles, respective data were analyzed on a series of 82 duodenal and 541 pancreatic NETs. In addition, the clinical records of 821 patients with duodenal or pancreatic NETs were reviewed for evidence of a somatostatinoma syndrome. Predominant or exclusive expression of somatostatin was found in 21 (26%) duodenal and 21 (4%) pancreatic NETs. They were classified as sporadic (n=31) or neurofibromatosis type 1 (NF1)-associated duodenal NETs (n=3), gangliocytic paragangliomas (GCPGs; n=6), or poorly differentiated neuroendocrine carcinomas (pd…
Long-term safety and efficacy of subcutaneous pasireotide in patients with Cushing’s disease: interim results from a long-term real-world evidence st…
2019
Abstract Purpose Clinical trials have demonstrated the favorable efficacy/safety profile of pasireotide in patients with Cushing’s disease (CD). We report interim long-term results of an ongoing real-world evidence study of subcutaneous pasireotide in patients with CD. Methods Adults with CD receiving pasireotide, initiated before (prior-use) or at study entry (new-use), were monitored for ≤ 3 years during a multicenter observational study (http://clinicaltrials.gov identifier NCT02310269). Primary objective was to assess long-term safety of pasireotide alone or with other CD therapies. Results At the time of this interim analysis, 127 patients had received pasireotide (new-use, n = 31; pri…
Role of Octreoscan and Correlation with MR Imaging in Graves' Ophthalmopathy
1995
Since the identification of somatostatin receptors on lymphocytes, orbital infiltration with mononuclear cells in Graves' ophthalmopathy has provided a rationale for receptor imaging with the radiolabeled somatostatin analog Octreotide. In 40 patients with Graves' ophthalmopathy and 10 controls, 110 MBq indium-Octreotide were administered i.v., and scans were performed at 4 and 24 h after injection. An uptake ratio between the orbits and the brain was determined. In 20 ophthalmophathy patients, magnetic resonance imaging (MRI) of the orbits was performed and the T2 relaxation time was measured within the rectus muscles. Compared to controls (4 h Octreotide uptake: median 6.0 counts/pixel/MB…
The medical treatment with pasireotide in Cushing’s disease: an Italian multicentre experience based on “real-world evidence”
2019
A phase III study has demonstrated that 6-month pasireotide treatment induced disease control with good safety in 15–26% of patients with Cushing’s disease (CD). The aim of the current study was to evaluate the 6-month efficacy and safety of pasireotide treatment according to the real-world evidence. Thirty-two CD patients started pasireotide at the dose of 600 µg twice a day (bid) and with the chance of up-titration to 900 µg bid, or down-titration to 450 or 300 µg bid, on the basis of urinary cortisol (UC) levels or safety. Hormonal, clinical and metabolic parameters were measured at baseline and at 3-month and 6-month follow-up, whereas tumour size was evaluated at baseline and at 6-mont…