Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
258 result(s) for "Hormones, Ectopic - analysis"
Sort by:
Antagonism of ghrelin receptor reduces food intake and body weight gain in mice
Background and aims: Ghrelin, an endogenous ligand for growth hormone secretagogue receptor (GHS-R), is an appetite stimulatory signal from the stomach with structural resemblance to motilin. We examined the effects of the gastric peptide ghrelin and GHS-R antagonists on energy balance and glycaemic control in mice. Materials and methods: Body weight, fat mass, glucose, insulin, and gene expression of leptin, adiponectin, and resistin in white adipose tissue (WAT) were measured after repeated administrations of ghrelin under a high fat diet. Gastric ghrelin gene expression was assessed by northern blot analysis. Energy intake and gastric emptying were measured after administration of GHS-R antagonists. Repeated administration of GHS-R antagonist was continued for six days in ob/ob obese mice. Results: Ghrelin induced remarkable adiposity and worsened glycaemic control under a high fat diet. Pair feeding inhibited this effect. Ghrelin elevated leptin mRNA expression and reduced resistin mRNA expression. Gastric ghrelin mRNA expression during fasting was increased by a high fat diet. GHS-R antagonists decreased energy intake in lean mice, in mice with diet induced obesity, and in ob/ob obese mice; it also reduced the rate of gastric emptying. Repeated administration of GHS-R antagonist decreased body weight gain and improved glycaemic control in ob/ob obese mice. Conclusions: Ghrelin appears to be closely related to excess weight gain, adiposity, and insulin resistance, particularly under a high fat diet and in the dynamic stage. Gastric peptide ghrelin and GHS-R may be promising therapeutic targets not only for anorexia-cachexia but also for obesity and type 2 diabetes, which are becoming increasingly prevalent worldwide.
Acromegaly Due to Secretion of Growth Hormone by an Ectopic Pancreatic Islet-Cell Tumor
THE clinical features of acromegaly result directly or indirectly from sustained hypersecretion of growth hormone. 1 2 3 Somatotroph-cell adenomas, or in rare cases hyperplasia, constitute the pathologic pituitary lesions causing acromegaly. 4 , 5 Also in rare cases, acromegaly may be caused by ectopic somatotroph-cell adenomas in the sphenoid or parapharyngeal sinuses. 4 , 5 Attention has recently been focused on the elaboration of growth hormone–releasing factors by carcinoid 6 and pancreatic islet-cell tumors 7 causing acromegaly. The structure of human growth hormone–releasing factor was, in fact, first elucidated from two such pancreatic tumor extracts, which were shown to stimulate growth hormone release both in vitro and in vivo. 8 , 9 Ectopic . . .
Pituitary Tumors Containing Cholecystokinin
We found small amounts of cholecystokinin in the normal human adenohypophysis and therefore examined pituitary tumors from 87 patients with acromegaly, Cushing's disease, Nelson's syndrome, prolactinoma, or inactive pituitary adenomas. Five adenomas associated with Nelson's syndrome contained increased amounts of cholecystokinin, the concentrations being extremely high in two: 8281 and 13,453 pmol per gram as compared with <30 pmol per gram in normal pituitary glands. The cholecystokinin concentrations were moderately increased in adenomas from another 12 patients, of whom 5 had Cushing's disease and 7 acromegaly with adenomas containing ACTH. The cholecystokinin peptides from the tumors were smaller and less sulfated than cholecystokinin from normal pituitary glands. We conclude that ACTH-producing pituitary cells may also produce an altered form of cholecystokinin. (N Engl J Med 1987; 316:1244–7.) TUMORS secreting the enteropancreatic hormones gastrin, 1 glucagon, 2 insulin, 3 pancreatic polypeptide, 4 somatostatin, 5 , 6 and vasoactive intestinal polypeptide 7 are well known. Paradoxically, tumors producing one of the oldest known gut hormones, cholecystokinin, have not been described. We have therefore used sequence-specific radioimmunoassays 8 to look for cholecystokinin tumors, but the search in patients with enteropancreatic tumors has so far been unsuccessful. Because we recently found small amounts of cholecystokinin in the human anterior pituitary, 9 we have now examined a large number of pituitary tumors. Methods Pituitary Tumors and Tissue Pituitary tumors were obtained from patients undergoing neurosurgery. Fifteen were from patients with Cushing's disease . . .
Subunits of Human Chorionic Gonadotropin: Unbalanced Synthesis and Secretion by Clonal Cell Strains Derived from a Bronchogenic Carcinoma
Three clones of ectopic hormone-producing cells from a single human neoplasm (bronchogenic carcinoma) show different rates of synthesis and secretion of chorionic gonadotropin and its alpha and beta subunits. For each clone, the amount of one or the other subunit always exceeded that of the complete hormone molecule. These findings may be analogous to unbalanced immunoglobulin chain synthesis in certain forms of myeloma.
Somatostatin and adrenocorticotrophic hormone like immunoreactivity in small cell carcinoma of the lung
The immunocytological detection of adrenocorticotrophic hormone (ACTH) and somatotropin release inhibitor factor (SRIF) like immunoreactivity was carried out on tumour cells from bronchial brush smears in 39 cases of lung tumours. Results obtained were compared with the cytological and histological diagnosis and confirmed the high incidence of ACTH synthesis by malignant bronchial carcinoma cells: the same phenomenon also seems to occur for somatostatin. The concomitant detection of ACTH and SRIF like immunoreactivity seems to be highly suggestive of small cell carcinoma and indicates that the immunocytological detection of hormones carried out at the same time as cytological examination can improve the accuracy of the diagnosis.
Differences in outcomes of bilateral adrenalectomy in patients with ectopic ACTH producing tumor of known and unknown origin
Endogenous Cushing syndrome (CS) can be caused by ectopic corticotropin-producing tumors of known (EK) and unknown origin (EU). Bilateral adrenalectomy (BA) can be used as definite treatment of hypercortisolism in such cases. This study compared patients undergoing BA for CS secondary to EK vs EU. Retrospective review (1995–2017) of patients undergoing BA due to EK or EU. We analyzed demographic characteristics, laboratory values, intraoperative variables, surgical outcomes, and survival. 48 patients (26 EU, 22 EK) were identified. Serum cortisol and ACTH concentrations were similar. 92% of BA for EU were performed minimally invasively vs 77% for EK, P = 0.22. Complications occurred in 19% of EU and 4.5% EK, P = 0.2. Mean survival was 4.3 years for EU and 4.0 years for EK without difference in all-cause mortality P = 0.63. BA cure rate was 100% for CS in EU and EK. Morbidity, long term and all-cause mortality differences were not statistically significant between EK and EU. •Ectopic ACTH producing tumors (EA) can present high morbidity due to hypercortisolism.•EA of unknown (EU) and known origin (EK) have similar demographic and laboratory patterns.•Bilateral adrenalectomy (BA) can be used to cure hypercortisolism in patients with EU and EK.•Survival rates after BA are similar between EK and EU. Retrospective review analyzing differences in surgical outcomes for patients undergoing bilateral adrenalectomy as curative treatment for endogenous hypercortisolism secondary to ectopic ACTH-producing tumors of known and unknown origin.
Personalized Noninvasive Diagnostic Algorithms Based on Urinary Free Cortisol in ACTH-dependant Cushing's Syndrome
Abstract Context Current guidelines for distinguishing Cushing's disease (CD) from ectopic ACTH secretion (EAS) are questionable, as they use pituitary magnetic resonance imaging (MRI) as first-line investigation for all patients. CRH testing is no longer available, and they suggest performing inferior petrosal sinus sampling (BIPPS), an invasive and rarely available investigation, in many patients. Objective To establish noninvasive personalized diagnostic strategies based on the probability of EAS estimated from simple baseline parameters. Design Retrospective study. Setting University hospitals. Patients Two hundred forty-seven CD and 36 EAS patients evaluated between 2001 and 2023 in 2 French hospitals. A single-center cohort of 105 Belgian patients served as external validation. Results Twenty-four-hour urinary free cortisol (UFC) had the highest area under the receiver operating characteristic curve for discrimination of CD from EAS (.96 [95% confidence interval (CI), .92-.99] in the primary study and .99 [95% CI, .98-1.00] in the validation cohort). The addition of clinical, imaging, and biochemical parameters did not improve EAS prediction over UFC alone, with only BIPPS showing a modest improvement (C-statistic index .99 [95% CI, .97-1.00]). Three groups were defined based on baseline UFC: < 3 (group 1), 3-10 (group 2), and > 10 × the upper limit of normal (group 3), and they were associated with 0%, 6.1%, and 66.7% prevalence of EAS, respectively. Diagnostic approaches performed in our cohort support the use of pituitary MRI alone in group 1, MRI first followed by neck-to-pelvis computed tomography scan (npCT) when negative in group 2, and npCT first followed by pituitary MRI when negative in group 3. When not combined with the CRH test, the desmopressin test has limited diagnostic value. Conclusion UFC accurately predicts EAS and can serve to define personalized and noninvasive diagnostic algorithms.
Dynamic Testing for Differential Diagnosis of ACTH-Dependent Cushing Syndrome: A Systematic Review and Meta-analysis
Abstract Context Diagnostic accuracy of testing currently used for the differential diagnosis of Cushing disease (CD) vs ectopic adrenocorticotropic hormone secretion (EAS) is difficult to interpret. Objective The present study aimed to identify and evaluate the diagnostic accuracy of the corticotropin-releasing hormone (CRH) test, the desmopressin test, and the high-dose dexamethasone suppression test (HDDST) when used to establish a CD or EAS diagnosis. Methods This study is a systematic review of the literature and meta-analysis. MEDLINE, OVID, and Web of Science databases were searched for articles published between 1990 and 2021. Articles included described at least 1 test(s) (CRH, desmopressin, or HDDST) and the diagnostic reference standard(s) (histopathology, petrosal sinus sampling, surgical remission, imaging, and long-term follow-up) used to establish a CD or EAS diagnosis. Results Sixty-two studies were included: 43 reported the use of the HDDST; 32, the CRH test; and the 21, the desmopressin test. The CRH test was found to have the highest sensitivity in detecting CD (ACTH 86.9%, 95% CI 82.1-90.6, cortisol 86.2%, 95% CI 78.3-91.5) and the highest specificity in detecting EAS (ACTH 93.9%, 95% CI 87-98.3, cortisol 89.4%, 95% CI 82.8-93.7). This resulted in a high diagnostic odds ratio (58, 95% CI 43.25-77.47), large area under the curve, and a receiver operating characteristic of 0.934. The diagnostic accuracy of the HDDST and desmopressin test was lower than that of the CRH test. Conclusion The meta-analysis indicates that a patient with a positive ACTH response after a CRH test is highly likely to have CD. Further studies analyzing role of dynamic testing in addition to imaging are needed.
Single-cell transcriptome analysis identifies a unique tumor cell type producing multiple hormones in ectopic ACTH and CRH secreting pheochromocytoma
Ectopic Cushing’s syndrome due to ectopic ACTH&CRH-secreting by pheochromocytoma is extremely rare and can be fatal if not properly diagnosed. It remains unclear whether a unique cell type is responsible for multiple hormones secreting. In this work, we performed single-cell RNA sequencing to three different anatomic tumor tissues and one peritumoral tissue based on a rare case with ectopic ACTH&CRH-secreting pheochromocytoma. And in addition to that, three adrenal tumor specimens from common pheochromocytoma and adrenocortical adenomas were also involved in the comparison of tumor cellular heterogeneity. A total of 16 cell types in the tumor microenvironment were identified by unbiased cell clustering of single-cell transcriptomic profiles from all specimens. Notably, we identified a novel multi-functionally chromaffin-like cell type with high expression of both POMC (the precursor of ACTH) and CRH, called ACTH+&CRH + pheochromocyte. We hypothesized that the molecular mechanism of the rare case harbor Cushing’s syndrome is due to the identified novel tumor cell type, that is, the secretion of ACTH had a direct effect on the adrenal gland to produce cortisol, while the secretion of CRH can indirectly stimulate the secretion of ACTH from the anterior pituitary. Besides, a new potential marker (GAL) co-expressed with ACTH and CRH might be involved in the regulation of ACTH secretion. The immunohistochemistry results confirmed its multi-functionally chromaffin-like properties with positive staining for CRH, POMC, ACTH, GAL, TH, and CgA. Our findings also proved to some extent the heterogeneity of endothelial and immune microenvironment in different adrenal tumor subtypes.