Histological analysis of elastic cartilages treated with alkaline solution / Análise histológica de cartilagens elásticas tratadas com solução alcalina

The elastic cartilage is composed by chondroblasts and chondrocytes, extracellular matrix and surrounded by perichondrium. It has a low regeneration capacity and is a challenge in surgical repair. One of obstacles in engineering a structurally sound and long-lasting tissue is selecting the most appropriate scaffold material. One of the techniques for obtaining biomaterials from animal tissues is the decellularization that decreases antigenicity. In this work, alkaline solution was used in bovine ear elastic cartilages to evaluate the decellularization and the architecture of the extracellular matrix. The cartilages were treated in alkaline solution (pH13) for 72 hours and lyophilized to be compared with untreated cartilages by histological analysis (hematoxylin-eosin, Masson's trichrome and Verhoeff slides). Areas of interest for cell counting and elastic fiber quantification were delineated, and the distribution of collagen and elastic fibers and the presence of non-fibrous proteins were observed. The results demonstrated that the alkaline solution caused 90% decellularization in the middle and 13% in the peripheral region, and maintenance of the histological characteristics of the collagen and elastic fibers and non-fibrous protein removal. It was concluded that the alkaline solution was efficient in the decellularization and removal of non-fibrous proteins from the elastic cartilages of the bovine ear.(AU)

A cartilagem elástica é composta por condroblastos e condrócitos, matriz extracelular e envolta por pericôndrio. Possui uma baixa capacidade de regeneração e é um desafio em reparos cirúrgicos. Um dos obstáculos na engenharia de tecido estruturalmente sólido e de longa duração é a seleção do material de arcabouço mais adequado. Uma das técnicas para obtenção de biomateriais oriundos de tecidos animais é a descelularização, que diminui a antigenicidade. Neste trabalho, foi utilizada solução alcalina em cartilagem elástica auricular bovina para avaliar a descelularização e a arquitetura da matriz extracelular. As cartilagens foram tratadas em solução alcalina (pH13) durante 72 horas e liofilizadas, e comparadas com cartilagens não tratadas por análise histológica (hematoxilina-eosina, tricrômio de Masson e Verhoeff). Foram determinadas as áreas de interesse para contagem celular e quantificação de fibras elásticas, observada a distribuição de colágeno e fibras elásticas e a presença de proteínas não fibrosas. Os resultados demonstraram que a solução alcalina causou 90% de descelularização na região central e 13% na região periférica, manutenção das características histológicas do colágeno e fibras elásticas e remoção das proteínas não fibrosas. Concluiu-se que a solução alcalina foi eficiente na descelularização e retirada de proteínas não fibrosas de cartilagens elásticas da orelha de bovinos.(AU)

Three different clinical faces of the same histopathological entity: hair follicle nevus, trichofolliculoma and accessory tragus

AbstractBACKGROUND:Hair follicle nevus is a rare, congenital hamartoma with follicular differentiation characterized histologically by numerous, tiny, mature hair follicles. Trichofolliculoma, the histopathological features of which are quite similar to those of hair follicle nevus, is also a hamartoma that differs from hair follicle. Accessory tragus is a relatively common, benign congenital abnormality of the external ear with an incidence rate of 1 to 10 per 1,000 live births.OBJECTIVE:This study seeks to assess the discriminatory value of currently available, histological criteria in the differential diagnosis of hair follicle nevus, accessory tragi and trichofolliculoma.METHODS:Twenty-one patients comprising 9 cases of hair follicle nevus, 8 accessory tragi patients and 4 trichofolliculoma cases, were recruited to perform the study.RESULTS:There were 10 males and 11 females in the study group. No significant difference was observed between the three study groups in terms of age, gender or histopathological parameters such as density of hair follicles, subcutaneous fat score and presence of connective tissue framework. Cartilaginous component was seen in 8 cases that were diagnosed as accessory tragi, while central cyst and radiating hair follicles were seen in 4 cases which were diagnosed as trichofolliculoma.CONCLUSION:The results of our study showed that diagnostic discrimination of these diseases could be made only with the clinicopathologic correlation because of their clinical and histopathological similarities.

Clinical Experience of Sturdy Elevation of the Reconstructed Auricle

BACKGROUND: The ear is composed of elastic cartilage as its framework, and is covered with a thin layer of skin. Auricular reconstruction using autogenous cartilage in microtia patients requires delicacy. This paper reports clinical experiences related to elevation of reconstructed ear in the last 11 years. METHODS: This study was based on 68 congenital microtia patients who underwent auricular elevation in our hospital. Among these 68 patients, 47 patients were recruited. We compared the differences in the ear size, auriculocephalic angle, and conchal depth with those in the opposite ear, and the patients' satisfaction levels were investigated using a survey. RESULTS: The difference in the sizes of the two ears was less than or equal to 5 mm in 32 patients, 5 to 10 mm in 10 patients, and greater than or equal to 10 mm in 5 patients. The difference in the auriculocephalic angles of the two ears was less than or equal to 10 degrees in 14 patients, 10 to 20 degrees in 26 patients, and greater than or equal to 20 degrees in 7 patients. The difference in the conchal depths of the two ears was less than or equal to 5 mm in 24 patients, 5 to 10 mm in 19 patients, and greater than or equal to 10 mm in 4 patients. The average grade of 3.9 points out of 5 points was obtained by the patients with satisfactory surveys. CONCLUSION: We could make enough protrusion and maintain the three-dimensional shape for a long time to satisfy our patients.

Expression of carbonic anhydrase IX in human fetal joints, ligaments and tendons: a potential marker of mechanical stress in fetal development? / 대한해부학회지

Carbonic anhydrase type IX (CA9) is known to express in the fetal joint cartilage to maintain pH against hypoxia. Using paraffin-embedded histology of 10 human fetuses at 10-16 weeks of gestation with an aid of immunohistochemistry of the intermediate filaments, matrix components (collagen types I and II, aggrecan, versican, fibronectin, tenascin, and hyaluronan) and CA9, we observed all joints and most of the entheses in the body. At any stages examined, CA9-poisitive cells were seen in the intervertebral disk and all joint cartilages including those of the facet joint of the vertebral column, but the accumulation area was reduced in the larger specimens. Glial fibrillary acidic protein (GFAP), one of the intermediate filaments, expressed in a part of the CA9-positive cartilages. Developing elastic cartilages were positive both of CA9 and GFAP. Notably, parts of the tendon or ligament facing to the joint, such as the joint surface of the annular ligament of the radius, were also positive for CA9. A distribution of each matrix components examined was not same as CA9. The bone-tendon and bone-ligament interface expressed CA9, but the duration at a site was limited to 3-4 weeks because the positive site was changed between stages. Thus, in the fetal entheses, CA9 expression displayed highly stage-dependent and site-dependent manners. CA9 in the fetal entheses seemed to play an additional role, but it was most likely to be useful as an excellent marker of mechanical stress at the start of enthesis development.

Correction of the Short Nose using Derotation Graft

Among several techniques to maintain the lengthened cartilagenous tip structure, septal extension graft with septal cartilage or rib cartilage is most widely used. But in many cases, nasal tip rigidity with unnatural appearance on smiling is one of the major drawbacks of septal extension graft. The authors used a piece of elastic cartilage graft harvested form ear that can act as a cushion buffer between alar cartilage and septum instead of directly fixing the alar cartilage to extended septum for obtaining a less stiff nasal tip with sufficient nasal tip elongation. We called this graft "derotation graft". Derotation graft was performed in 1197 patients via the open nasal approach. Among them, 432(36%) patients had preoperative short nose deformity and 765(64%) patients developed intraoperative cephalic rotation of the tip resulting from procedures for tip projection such as columellar strut. Excellent results were achieved in 1110(93%) patients. 87(7%) patients had unsatisfactory results requiring a revision surgery because of overcorrection or undercorrection of tip rotation, poor tip projection and visible graft on supratip. Derotation graft is a simple, and effective procedure for short nose correction preventing with less post-operative nasal tip rigidity.

A Case of Auricular Ossification

Ectopic ossification refers to the process of new bone formation in sites that normally do not ossify. The auricle is composed of elastic cartilage, and hence is a pliable structure. Auricular ossification is a rare condition that might be caused by injurious processes, including frostbite, physical trauma, and inflammation as well as processes related to metabolic or endocrine disorders. Here, we report a case of unilateral auricular ossification in a 53-year-old Korean man who had previously rubbed his ear repeatedly with his hand.

A Case Report of Focal Ossification of the Auricular Cartilage

PURPOSE: The focal ossification of auricular cartilage is an unusual clinical entity in which the ear becomes partially or totally rigid and immalleable. This condition may result from cold injury, local trauma, inflammation, or various systemic diseases. Patients may feel mild discomfort, but there are usually no other serious symptoms. We present a case of focal ossification of auricular cartilage in which the cause is unknown. METHODS: A healthy 58-year-old man presented with a 2-year history of hard mass of right posterior auricular area. He denied any precipitating historical events like cold injury and inflammation. Routine testing did not demonstrate systemic abnormalities. Ultrasonographic examination revealed a 22 x 10 x 11 mm sized heterogenous isoechoic mass showing an acoustic shadow. RESULTS: Excisional biopsy was performed under local anesthesia. Histological examination revealed the ossification with deposition of trabecular bone in normal elastic cartilage. The patient was healed without any problems and satisfied with the result. CONCLUSION: We report clinical experience of focal ossification of auricular cartilage, which is quite a rare clinical entity. It should be considered that there is the possibility of ossification of cartilage when it meets the benign mass of the ear.

A Case of Accessory Tragus on the Posterior Neck / 대한피부과학회지

Cervical accessory tragus is a rare congenital malformation presenting at birth as a firm nodule on the neck along the anterior edge of the sternocleidomastoid muscle. It has also been reported under different names, such as elastic cartilage choristoma of the neck, Meckel's cartilaginous remnant, cervical tab, cervical auricle, and wattle. Histologically, cervical accessory tragus is composed of numerous hair follicles, and a prominent connective tissue framework in the subcutaneous fat and central core of cartilage. We report a case of an 8-year-old female who presented with a solitary flesh colored papule on the posterior neck that was histopathologically diagnosed as cervical accessory tragus.

A Case of Accessory Tragus on the Posterior Neck / 대한피부과학회지

Cervical accessory tragus is a rare congenital malformation presenting at birth as a firm nodule on the neck along the anterior edge of the sternocleidomastoid muscle. It has also been reported under different names, such as elastic cartilage choristoma of the neck, Meckel's cartilaginous remnant, cervical tab, cervical auricle, and wattle. Histologically, cervical accessory tragus is composed of numerous hair follicles, and a prominent connective tissue framework in the subcutaneous fat and central core of cartilage. We report a case of an 8-year-old female who presented with a solitary flesh colored papule on the posterior neck that was histopathologically diagnosed as cervical accessory tragus.

The Morphologic Study of Elastic Structures in the Developing Murine Eustachian Tube / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Detailed information on how an epithelial differentiation and elastic structures occurred in the developing eustachian tube would be helpful in understanding both normal physiology and pathology of the tubotympanum. This study was undertaken to establish elastic structures such as cartilage, elastic fiber, and collagen fiber in the embryonic mouse eustachian tube at a stage when epithelial differentiation is taking place. MATERIALS AND METHOD: Thirty four mice (BALB/c mouse), aged from gestational day 11 to postnatal day 21, were investigated using Verhoeff stain, Masson trichrome stain and alpha-1 antitrypsin immunohistochemistry. RESULTS: The cartilage-like structures were first found after birth, however, matured cartilages appeared at postnatal day 7. The elastic fibers and collagen fibers surrounding cartilage were abundantly found about 5 days after birth. alpha-1 antitrypsin, which is an strong inhibitor of elastase, began to be immunolabelled at gestational day 16. Its expression has been significantly increased after birth. CONCLUSION: Although the epithelial differentiation and maturation in eustachian tube occured at late embryonal stage, the elastic structures have developed and matured after birth. These findings might be a explanation to why young children are highly susceptible to otitis media.

Tissue Engineered Cartilage Formation using Human Hyaline Chondrocytes and Elastic Chondrocytes

The purpose of this study was to evaluate the influence of different types of PLGA scaffolds on the formation of human auricular and septal cartilages. The scaffolds were formed in tubular shape from 110,000 g/mol PLGA (poly lactic glycolic acid) and 220,000 g/mol one. Elastic cartilage was taken from the ear of a patient aged under 20 years old and hyaline cartilage from the nasal septum. The chondrocytes cells were then isolated by Klausburn method. After second passages, the chondrocytes were seeded on the PLGA scaffolds followed by in vitro culture for one week. The cells-PLGA scaffold complex was implanted at the back of nude mouses for 8 weeks. The tissue engineered cartilages were separated from nude mouse and examined histologically after staining with the Hematoxylin Eosin and Verhoeff. The formation of extracellular matrix and the porosity of the scaffolds were examined by scanning electron microscopy. The pores were well formed and uniformly distributed in both 110,000 g/mol and 220,000 g/mol PLGA scaffolds. The extracellular matrix was formed better in 110,000 g/mol PLGA compared to 220,000 g/mol one. And hyaline cartilage was proliferated better in vitro culture than elastic cartilage. After 8 weeks in vivo culture, cartilage was well formed with 110,000 g/mol PLGA, however lumen was collapsed. In contrast with 220,000 g/mol PLGA scaffold, neocartilage was formed in minimal amount while the architecture of scaffold was well preserved. Elastic cartilage seems to be better than hyaline one in terms of neocartilage formation. From the analysis after Verhoeff staining the cartilages, the neocartilage from elastic cartilage was proved to be elastic cartilage. In summary, there was no significant difference between elastic cartilage and hyaline cartilage in their morphologies, proliferation rates and the degree of cartilage formation since they were tissue engineered, however marked difference was found in neocartilage formation and preservation of scaffold architecture between 110,000 g/mol PLGA scaffold and 220,000 one. From the present findings, it is concluded that the influence of scaffold materials is significantly higher than that of different types of cells on the formation of new tissues.

Two Cases of Congenital Preauricular Fistula / 대한피부과학회지

The auricle develops from six auricular tubercles which originate from the mesenchyme of the first and second branchial arch. If a defective fusion of these tubercles occur, a preauricular fistula may be formed. We report two cases of congenital preauricular fistula manifested by soft nodules with external openings on the left preauricular area. Histologically, the fistulas are lined by stratified squamous epithelium, and elastic cartilage. and chronic inflammatory cell infiltration are also present.

Morphological changes of the epiglottis with aging: a radiological study

In man the epiglottis is a thin lamella of yellow elastic cartilage. The upper part is free and is known asleaf and lower part participates in the formation of the anterior wall of the vestibule of the larynx. Theipithelial covering extends forwards onto the base of the tongue over the medial glossoepiglottic folds. The sidesof epiglottis are connected with the cartilages of Wrisberg and arytenoid cartilage by the aryepiglottic fold. Inview of these anatomical complexities, the function and physiology of the epiglottis have been debated sinceMagendi(1815), who proposed the theory that the epiglottis acts as a flap valve to prevent food entering thewindpipe, and who found that he could remove the free part of the epiglottis in dog without spoiling the dog.Follwoing the introduction of laryngoscopy(Garcia, 1815; Liston, 1840; Czermark, 1861) and modern cineradiographicequipments in 1950's, the anatomy and physiology of epiglottis has become much clearrer. Age as it is seen on thelateral x-ray of the neck. In the present study we have made an attempt to systematically analyze aging changes ofthe epiglottis in the lateral x-ray of the neck in 245 healthy adults. The age ranged from 16 to 65 years old.Based on our observation the epiglottis was classified into type A, B, and C according to their curvatures. Thus,type A represented those with posterior curvature, type B those with straight epiglottis and type C anteriorcurvature. Type C was sudivided into I, II and III according to the degree of curvature. Thus, type C-I, C-II andC-III represented mild, moderated and marked anterior curvature, respectively. Type A epiglottis was found in thesecond, third and fourth decades and type C-III in the older age group. Type A was least comon and type C mostprevalent. It seems that the epiglottis inclines anteriorly with backward curvature with age (p<0.0001).