Structure and composition of arytenoid cartilage of the bullfrog (Lithobates catesbeianus) during maturation and aging

History of Previous Surgical Resection Promotes the Sclerosis of the Arytenoid Cartilage in Patients With Laryngeal Contact Granuloma

OBJECTIVES

To explore the relationship between arytenoid cartilage sclerosis and a history of previous surgical resection in patients with laryngeal contact granuloma.

METHODS

167 patients with laryngeal contact granuloma treated from March 2016 to December 2018 were studied. The high-resolution computed tomography (HRCT) data of the sclerosis of arytenoid cartilage is divided into asymmetric sclerosis, bilateral sclerosis, and no sclerosis according to the range of sclerosis. The proportions of various ranges of sclerosis in two subgroups of patients were compared to patients with and without a history of previous surgical resection.

RESULTS

The arytenoid cartilage sclerosis rate of 167 patients was 69.46%. The exact probability method showed that P < 0.001, suggesting that the distribution of arytenoid cartilage sclerosis was different in patients with and without a history of previous surgical resection, and there was a moderate correlation between the extent of arytenoid sclerosis and history of previous surgical resection (Cramer's V = 0.436, P < 0.001). There were 18 cases of bilateral sclerosis in patients with a history of previous surgical resection, of which 50% had contralateral recurrence after combined therapy (proton pump inhibitor (PPI) and glucocorticoid injection into granuloma via the thyrohyoid membrane approach), accounting for 75% of recurrence after combined therapy.

CONCLUSION

Surgery promotes the expansion of arytenoid sclerosis, Patients with bilateral arytenoid sclerosis are prone to recurrence of contralateral laryngeal contact granuloma.

Tadpole bioacoustics: Sound processing across metamorphosis

Many species of anuran amphibians (frogs and toads) undergo metamorphosis, a developmental process during which external and internal body morphologies transform dramatically as the animal transitions to a new ecosystem (from aquatic to terrestrial) and develops new behavior patterns (from filter-feeding to active pursuit of moving prey; from mostly mute to highly vocal). All sensory systems transform to some extent during metamorphosis, even in those "primitive" anuran species that remain fully aquatic in adult life. In this article, I review what is known about the development of the auditory system in anuran tadpoles. I identify crucial developmental windows for major maturational events in the ear and brainstem that showcase the structural and physiological reorganization of the substrates for hearing airborne sounds as the animal navigates the metamorphic transition. I argue that auditory development is dynamic and nonlinear, and I point out areas for future investigation. Understanding metamorphosis can shed light on how organisms adapt to major environmental challenges. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Aberrant activation of latent transforming growth factor-β initiates the onset of temporomandibular joint osteoarthritis

There is currently no effective medical treatment for temporomandibular joint osteoarthritis (TMJ-OA) due to a limited understanding of its pathogenesis. This study was undertaken to investigate the key role of transforming growth factor-β (TGF-β) signalling in the cartilage and subchondral bone of the TMJ using a temporomandibular joint disorder (TMD) rat model, an ageing mouse model and a Camurati–Engelmann disease (CED) mouse model. In the three animal models, the subchondral bone phenotypes in the mandibular condyles were evaluated by µCT, and changes in TMJ condyles were examined by TRAP staining and immunohistochemical analysis of Osterix and p-Smad2/3. Condyle degradation was confirmed by Safranin O staining, the Mankin and OARSI scoring systems and type X collagen (Col X), p-Smad2/3a and Osterix immunohistochemical analyses. We found apparent histological phenotypes of TMJ-OA in the TMD, ageing and CED animal models, with abnormal activation of TGF-β signalling in the condylar cartilage and subchondral bone. Moreover, inhibition of TGF-β receptor I attenuated TMJ-OA progression in the TMD models. Therefore, aberrant activation of TGF-β signalling could be a key player in TMJ-OA development.

Blocking the activity of a critical growth factor could help treat degenerative disease of the jaw joint, according to experiments in three rodent models. Xuedong Zhou from Sichuan University in Chengdu, China, examined the cartilage and adjoining layer of bone found at the ends of the jawbone in a rat model of temporomandibular joint disorder and in two related mouse models. In all three, the researchers observed tissue abnormalities consistent with what’s seen in humans with osteoarthritis of the jaw joint, a condition with no effective therapeutic options. They showed that transforming growth factor-β, a master regulatory protein, displayed aberrant signalling patterns in these tissues and that blocking this protein’s receptor with a drug attenuated the disease process. The findings help explain what drives jaw joint osteoarthritis — and point to a strategy for treating it.