The thyroid gland of vertebrates is considered to be homologous to the endostyle of non-vertebrate chordates (cephalochordates, urochordates), a key character for understanding the origin and evolution of the chordate body plan. In lampreys, the larval endostyle transforms into an adult thyroid gland during metamorphosis, reflecting evolutionary changes that occurred in the vertebrate lineage. Focussing on thyroid-like cells in the endostyle, we here relate morphologically visible steps of lamprey (Lampetra fluviatilis) endostyle differentiation to embryonic stages and determine the onset of thyroid-like function. Analysing lamprey endostyle development using semi-thin histological sections, immunohistochemical detection of thyroid hormone, and the molecular marker thyroid transcription factor1 (Ttf1) refines our current view of the homology between endostyle and thyroid gland. In contrast to earlier literature, we find that a duct always persists to connect the endostyle lumen to the pharynx, a structure that resembles the thyroglossal duct in thyroid development and could further support the homology between endostyle and thyroid. Before the onset of thyroid-like function, Ttf1 expression becomes restricted to the ventral part of the endostyle, on the one hand showing that dorsal thyroid-like cells produce thyroid hormone in the absence of Ttf1, and on the other suggesting that Ttf1 was initially involved in specifying ventral fates in the endostyle.
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http://dx.doi.org/10.1007/s00427-004-0450-0 | DOI Listing |
Cureus
December 2024
Nephrology, Yokohama Municipal Citizen's Hospital, Yokohama, JPN.
Hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI) is a novel class of orally administered medications for renal anemia in patients with end-stage renal disease (ESRD). Roxadustat, a HIF-PHI, has a structure similar to that of triiodothyronine and may work as an agonist for thyroid hormone receptor-beta in the pituitary gland and/or hypothalamus. Therefore, roxadustat may cause central hypothyroidism due to suppressing thyroid-stimulating hormone (TSH) release in the pituitary gland and/or thyrotropin-releasing hormone release in the hypothalamus.
View Article and Find Full Text PDFBMC Anesthesiol
January 2025
Department of Anesthesiology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkla, 90110, Thailand.
Background: A previous study showed that airway ultrasound, specifically the distance from the skin to the hyoid bone (DSHB), may be correlated with a higher risk of difficult mask ventilation (DMV). However, the study was conducted in Italy and lacks data for the Asian and Thai populations. This study aimed to predict DMV using pre-operative ultrasonography to measure the DSHB and from the skin to the thyroid isthmus (DSTI) in Thai patients undergoing elective surgery under general anesthesia.
View Article and Find Full Text PDFChirurgie (Heidelb)
January 2025
Klinik für Viszerale, Gefäß- und Endokrine Chirurgie, Universitätsmedizin Halle, Ernst-Grube-Str. 40, 06120, Halle/Saale, Deutschland.
Endocrine surgery in multimorbid, frail and geriatric patients is increasing, is often urgent and characterized by special risk constellations. Successful parathyroid gland surgery nearly always results in a marked improvement, irrespective of the specific risk profile of the patient. Except for critical intubation and mediastinal interventions in the risk profile, surgery of the thyroid glands is predominantly beneficial and justifiable even in frail patients.
View Article and Find Full Text PDFPheochromocytoma (PHEO) currently is considered to be malignant due to metastatic potential. One of the most common familial forms of PHEO is multiple endocrine neoplasia syndrome (MEN) type 2. The penetrance of PHEO in MEN2 syndrome is up to 50% of cases.
View Article and Find Full Text PDFInt Med Case Rep J
January 2025
Department of Neurology, The Lishui Hospital of Wenzhou Medical University, The First Affiliated Hospital of Lishui University, Lishui People's Hospital, Lishui, Zhejiang, 323000, People's Republic of China.
Primary amyloidosis (AL type) is a systemic disease that can lead to structural and functional damage to organs and tissues such as the kidney, heart and liver with non-specific symptoms. Most of the affected patients develop thyroid infiltration and thus diffuse enlargement of the thyroid gland, while cases leading to hypothyroidism are exceedingly rare. Some researchers have analyzed thyroid function in newly diagnosed patients with AL amyloidosis, and found that the incidence of overt hypothyroidism is only 7%.
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