scholarly journals Localised inhibition of FGF signalling in the third pharyngeal pouch is required for normal thymus and parathyroid organogenesis

Development ◽  
2012 ◽  
Vol 139 (18) ◽  
pp. 3456-3466 ◽  
Author(s):  
J. R. Gardiner ◽  
A. L. Jackson ◽  
J. Gordon ◽  
H. Lickert ◽  
N. R. Manley ◽  
...  
1917 ◽  
Vol 25 (1) ◽  
pp. 129-152 ◽  
Author(s):  
Edwards A. Park

1. Accessory lobes of thymus, derived from the third pharyngeal pouch, occurring in close association with the parathyroids from the third pouch, were found in serial section of the cervical tissues of eleven out of fourteen guinea pigs, and probably would have been found in all fourteen but for a technical error. 2. It is probable, therefore, that accessory lobes of thymus having this situation and origin are usually, if not always, present in the guinea pig. 3. Additional accessory lobes of thymus belonging to, but at some distance from the main lobe were also present in several of the animals. 4. The discovery of these accessory lobes makes it certain that the guinea pig is unsuitable material for complete thymectomy, and probably complete extirpation of the thymus in this animal is rarely, if ever accomplished. 5. The extirpation experiments of previous investigators in the guinea pig must now be regarded as partial extirpations, and their results interpreted in that light. 6. Extirpation of the thymus in the guinea pig produced no changes in the writer's experiments. 7. The study of the serial sections of the cervical tissues of the guinea pig indicates that Ruben's statements regarding the parathyroid derived from the fourth pharyngeal pouch in the guinea pig are correct,—that it is much smaller than parathyroid III, may be rudimentary, and is sometimes absent at least on one side. 8. No accessory lobe of thymus was found accompanying the parathyroid from the fourth pouch, a finding also bearing out Ruben's statement that no thymus anlarge springs from the fourth pouch in the guinea pig.


2019 ◽  
Vol 2019 (12) ◽  
pp. 519-523 ◽  
Author(s):  
Anthony M Kordahi ◽  
Ron S Newfield ◽  
Stephen W Bickler ◽  
Jun Q Mo ◽  
Paritosh C Khanna ◽  
...  

ABSTRACT We describe a rare presentation of a symptomatic parathyroid adenoma located in an ectopic retropharyngeal position in a 13-year-old boy. Preoperative CT scan and MRI demonstrated the ectopic location of the parathyroid adenoma. The patient underwent successful parathyroidectomy with cure of his hyperparathyroidism. On pathologic exam, the specimen was made up of a parathyroid adenoma and adjacent thymic tissue, indicating that it was likely an undescended lower parathyroid gland arising from the third pharyngeal pouch. Ectopic retropharyngeal parathyroid adenomas are very rare and to our knowledge, none have been previously described in adolescents.


Blood ◽  
2009 ◽  
Vol 113 (13) ◽  
pp. 2976-2987 ◽  
Author(s):  
Dil Afroz Sultana ◽  
Shuhei Tomita ◽  
Michito Hamada ◽  
Yasuyuki Iwanaga ◽  
Yuki Kitahama ◽  
...  

Abstract The thymus provides a microenvironment that induces the differentiation of T-progenitor cells into functional T cells and that establishes a diverse yet self-tolerant T-cell repertoire. However, the mechanisms that lead to the development of the thymus are incompletely understood. We report herein the results of screening for genes that are expressed in the third pharyngeal pouch, which contains thymic primordium. Polymerase chain reaction (PCR)–based cDNA subtraction screening for genes expressed in microdissected tissues of the third pharyngeal pouch rather than the second pharyngeal arch yielded one transcription factor, MafB, which was predominantly expressed in CD45−IA−PDGFRα+ mesenchymal cells and was detectable even in the third pharyngeal pouch of FoxN1-deficient nude mice. Interestingly, the number of CD45+ cells that initially accumulated in the embryonic thymus was significantly decreased in MafB-deficient mice. Alterations of gene expression in the embryonic thymi of MafB-deficient mice included the reduced expression of Wnt3 and BMP4 in mesenchymal cells and of CCL21 and CCL25 in epithelial cells. These results suggest that MafB expressed in third pharyngeal pouch mesenchymal cells critically regulates lymphocyte accumulation in the embryonic thymus.


Author(s):  
Georgios Velimezis ◽  
Argyrios Ioannidis ◽  
Sotirios Apostolakis ◽  
Maria Chorti ◽  
Charalampos Avramidis ◽  
...  

Summary During embryogenesis, the thymus and inferior parathyroid glands develop from the third pharyngeal pouch and migrate to their definite position. During this process, several anatomic variations may arise, with the thyroid being one of the most common sites of ectopic implantation for both organs. Here, we report the case of a young female patient, who underwent total thyroidectomy for papillary carcinoma of the thyroid. The patient’s history was remarkable for disorders of the genitourinary system. Histologic examination revealed the presence of well-differentiated intrathyroidal thymic tissue, containing an inferior parathyroid gland. While each individual entity has been well documented, this is one of the few reports in which concurrent presentation is reported. Given the fact that both the thymus and the inferior parathyroid are derivatives of the same embryonic structure (i.e. the third pharyngeal pouch), it is speculated that the present condition resulted from a failure in separation and migration during organogenesis. Learning points: Intrathyroidal thymus and parathyroid are commonly found individually, but rarely concurrently. It is a benign and asymptomatic condition. Differential diagnosis during routine workup with imaging modalities can be challenging.


Author(s):  
Geoffrey N. Hendy ◽  
David Goltzman

Humans have two pairs of parathyroid glands lying in the anterior cervical region. The fetal parathyroid glands begin developing at 5 weeks from the third and fourth pharyngeal pouches. The third pharyngeal pouch, which contains tissue that will become the thymus and parathyroid, migrates downward and gives rise to the two inferior parathyroid glands normally located at the lower poles of the thyroid. The fourth pharyngeal pouch does not migrate and gives rise to the two upper parathyroid glands, which normally are attached to the upper poles of the thyroid (1).


2018 ◽  
Author(s):  
Erica Hasten ◽  
Bernice E Morrow

SummaryThe mechanisms required for segmentation of the pharyngeal apparatus to individual arches are not precisely delineated in mammalian species. Here, using conditional mutagenesis, we found that two transcription factor genes, Tbx1, the gene for 22q11.2 deletion syndrome and Foxi3, genetically interact in the third pharyngeal pouch endoderm for thymus and parathyroid gland development. We found that Tbx1 is autonomously required for the endoderm to form a temporary multilayered epithelium while invaginating. E-cadherin for adherens junctions remains expressed and cells in the apical boundary express ZO-1. Foxi3 is required autonomously to modulate proliferation and promote later restoration of the endoderm to a monolayer once the epithelia meet after invagination. Completion of this process cooccurs with expression of Alcam needed to stabilize adherens junctions and extracellular, Fibronectin. These processes are required in the third pharyngeal pouch to form the thymus and parathyroid glands, disrupted in 22q11.2 deletion syndrome patients.


2006 ◽  
Vol 293 (2) ◽  
pp. 499-512 ◽  
Author(s):  
Dan Zou ◽  
Derek Silvius ◽  
Julie Davenport ◽  
Raphaelle Grifone ◽  
Pascal Maire ◽  
...  

2020 ◽  
pp. 185-196
Author(s):  
Jad M. Abdelsattar ◽  
Moustafa M. El Khatib ◽  
T. K. Pandian ◽  
Samuel J. Allen ◽  
David R. Farley

The parathyroid glands develop from the endoderm: the superior glands from the fourth pharyngeal pouch, and the inferior glands from the third pharyngeal pouch. Parathyroid glands are usually found on the posterior surface of the thyroid gland. Chief cells secrete PTH, which has a half-life of 3 to 6 minutes. Primary HPT is most often asymptomatic and serendipitously found when the serum calcium value is increased on routine testing. The parathyroid glands can be evaluated with US, CT, MRI, or sestamibi scanning. Cervical exploration for primary HPT involves resection of a solitary adenoma in approximately 85% of patients. Injury to the RLN and superior laryngeal nerve does occur.


Sign in / Sign up

Export Citation Format

Share Document