Publications by authors named "R M Lechan"

Head and neck paragangliomas (HNPGLs) are typically slow-growing, hormonally inactive tumors of parasympathetic paraganglia. Inactivation of prolyl-hydroxylase domain-containing 2 protein causing indirect gain-of-function of hypoxia-inducible factor-2α (HIF-2α), encoded by EPAS1, was recently shown to cause carotid body hyperplasia. We previously described a syndrome with multiple sympathetic paragangliomas caused by direct gain-of-function variants in EPAS1 (Pacak-Zhuang syndrome, PZS) and developed a corresponding mouse model.

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The term 'fugitive acromegaly' was introduced by the neurosurgeons Bailey and Cushing in 1928 to describe subjects manifesting signs and symptoms of somatotroph hyperfunction with pituitary insufficiency. Currently, it identifies patients with subtle acromegalic dysmorphisms and inconsistent hormonal profile, possibly presenting only with hyperprolactinemia and related clinical symptoms. Patients have rapidly growing, locally invasive, relapsing pituitary macrotumors that can be classified as either acidophil stem cell tumors (ASCTs) or sparsely granulated somatotroph tumors (SGSTs), both of PIT1-lineage.

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Background: Hyponatremia is a common complication following endoscopic endonasal resection (EER) of pituitary adenomas. We report a single-center, multisurgeon study detailing baseline clinical data, outcomes, and factors associated with postoperative hyponatremia.

Methods: This was a retrospective cohort study of patients undergoing EER for pituitary adenoma at Tufts Medical Center.

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In contrast to mammals, birds have a higher basal metabolic rate and undertake wide range of energy-demanding activities. As a consequence, food deprivation for birds, even for a short period, poses major energy challenge. The energy-regulating hypothalamic homeostatic mechanisms, although extensively studied in mammals, are far from clear in the case of birds.

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Article Synopsis
  • * Researchers used retrograde and anterograde tracing techniques in rats and found that TRH neurons projecting to the TMN mainly originate from the tuberal lateral hypothalamus (TuLH).
  • * The findings suggest that TRH from TuLH could play a role in controlling food intake and energy balance by influencing histaminergic signaling in the TMN, potentially impacting homeostasis in rodents.
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