UNLABELLED The gastroprokinetic agent metoclopramide is known to stimulate catecholamine secretion from pheochromocytomas. The aim of the study was to investigate the mechanism of action of metoclopramide and expression of serotonin type 4 (5-HT(4)) receptors in pheochromocytoma tissues. Tissue explants, obtained from 18 pheochromocytomas including the tumor removed from a 46-year-old female pa...

Activin A (a homodimer of two activin betaA subunits) has been shown to induce the neuronal differentiation of rat pheochromocytoma PC12 cells. We studied activin A and its receptor gene expression in human pheochromocytomas in vivo and in vitro to clarify the potential involvement of activin A in the pathophysiology of these tumors. We first screened 20 pheochromocytomas and nine normal adrena...

BACKGROUND Von Hippel-Lindau (VHL) disease is an autosomal dominant inherited disease. It is relatively recent that type 2C was identified as a separate group solely presenting with pheochromocytomas. As an illustration, an interesting case is presented of a pregnant woman with refractory hypertension. It proved to be the first manifestation of bilateral pheochromocytomas. The family history ma...

Pheochromocytomas are derived from chromaffin cells of the adrenal medulla which synthesize and secrete catecholamines, thus affecting the cardiovascular system and metabolic processes. Pheochromocytoma is a tumor of the following multicarcinoma hereditary syndromes: type 2 multiple endocrine neoplasia, von Hippel-Lindau disease, type 1 neurofibromatosis and the pheochromocytomas/paragangliomas...

Giant pheochromocytomas are rare silent entities that do not present with the classical symptoms commonly seen in catecholamine-secreting tumors. In many cases they are accidentally discovered. The algorithm to diagnose a pheochromocytoma consists of biochemical evaluation and imaging of a retroperitoneal mass. The female patient in this case report presented with a palpable abdominal mass and ...

Pheochromocytomas in multiple endocrine neoplasia type 2 (MEN-2) express phenylethanolamine N-methyltransferase (PNMT), the enzyme that catalyzes conversion of norepinephrine to epinephrine, whereas those in von Hippel-Lindau (VHL) syndrome do not. Consequently, pheochromocytomas in MEN-2 produce epinephrine, whereas those in VHL syndrome produce mainly norepinephrine. This study examined wheth...

Paragangliomas/pheochromocytomas comprise rare tumors that arise from the extra-adrenal paraganglia, with an incidence of about 2 to 8 per million people each year. Approximately 40% of cases are due to genetic mutations in at least one out of more than 30 causative genes. About 25-30% of pheochromocytomas/paragangliomas develop under the conditions of a hereditary tumor syndrome a third of whi...

Pheochromocytomas are neuroendocrine tumors that can arise sporadically or be inherited as a familial disease, and they may occur in isolation or as part of a multitumor syndrome. Familial disease typically presents in younger patients with a higher risk of multifocality. Recently, the tumor suppressor MYC-associated factor X (MAX) gene has been implicated as a cause of familial isolated pheoch...

Pheochromocytomas can be a part of familial neoplastic syndromes, in which case they tend to be multiple and involve both adrenal glands. Therefore, sparing adrenocortical function represents a major concern while dealing with these hereditary lesions. Herein, we describe the clinical characteristics and the management strategy of a patient with von Hippel-Lindau (VHL) disease who had multiple,...

Point defects in silicon carbide are rapidly becoming a platform of great interest for single-photon generation, quantum sensing, and quantum information science. Photonic crystal cavities (PCCs) can serve as an efficient light-matter interface both to augment the defect emission and to aid in studying the defects' properties. In this work, we fabricate 1D nanobeam PCCs in 4H-silicon carbide wi...