Spindle cell carcinoma of the external auditory meatus with intracranial extension: histological, immunohistochemical and electron microscopic evaluation.

We present a case of squamous spindle cell carcinoma of the external auditory meatus in a 38-year-old man. The tumour was extended to the inner ear, the temporal bone, the middle cranial fossa and the meningo-cerebral tissue. The surgical intervention of temporo-occipital craniotomy removed most of the neoplasia. At pathologic examination, the tumour showed an undifferentiated spindle cell pattern. Immunohistochemistry with a large antibody panel found a weak positivity only to EMA. The diagnosis was made when the electron microscopy showed rare junctional structures and tonofilaments.

Differentiation of the secondary elastic cartilage in the external ear of the rat.

The cartilage in the external ear of the rat belongs to the group of secondary cartilages and it has a unique structural organization. The chondrocytes are transformed into typical adipose cells, the proteoglycan cartilage matrix is reduced to thin capsules around the cells and the rest of the extracellular matrix is occupied by a network of coarse elastic fibers. It appears late in development (16-day fetus) and needs more than one month for final development. The differentiation proceeds in several steps which partly overlap: the appearance of collagen fibrils, elastin fibers, the proteoglycan matrix, and the adipose transformation of chondrocytes. The phenotype of this cartilage and the course of its differentiation are very stable, even in very atypical experimental environmental conditions. The only exceptions are explants in organ culture in vitro and perichondrial regenerates. In these conditions the development of elastic fibers is slow and poor while the production of the proteoglycan matrix is abundant. The resulting cartilage then displays structural characteristics of hyaline cartilage rather than those of the initial elastic one.

Hamster ear model for sebaceous glands.

The ventral side of the earlobes of Syrian hamsters richly endowed with sebaceous glands. These glands are large and are similar to human sebaceous follicles since they have an infundibulum, a sebaceous duct, multiple lobules, and a pilary unit which enters from below into the gland. In this study we have measured gland size by planimetry,and cellular activity by autoradiography using tritiated thymidine and tritated histidine. Males have much larger glands in sagittal sections than do females(0.1750 mm2 vs 0.0727 mm2, p less than 0.001) and a higher labeling index (19.85% vs 14.3%, p less than 0.01). Injection of testosterone propionate increases the gland size in female hamsters to 0.2362 mm2 (p less than 0.001). The labeling index also increases. The turnover of the total gland population is 12 to 14 days. Androgen sensitivity, gland size, and turnover time make the sebaceous glands on the ventral surface of the hamster earlobe a suitable model for study.

Differentiation of extracellular matrix in the cellular cartilage ("Zellknorpel") of the mouse pinna.

Differentiation of cellular cartilage was studied in the mouse pinna with particular reference to matrix material. Fixation of glycosaminoglycans was performed by the use of acridine orange and elastin was identified by staining thin sections with tannic acid and uranyl acetate. Condensation of mesenchymal cells ("prechondroblasts") initiates the formation of a blastema of cartilaginous tissue at postnatal day 4. The synthesis of acidic glycosaminoglycans begins at postnatal day 8 when prechondroblasts transform to chondroblasts. Glycosaminoglycans can be detected within secretory vesicles of chondroblasts at postnatal day 8, in the extracellular space at postnatal day 13. Delicate collagen fibrils and elastic fiber microfibrils are seen between prechondroblasts and chondroblasts. Deposition of elastin begins at postnatal day 11. A network of elastic fibers and lamellae is formed, which replaces both collagen fibrils and elastic fiber microfibrils. In the interstice of mature cellular cartilage only elastin and proteoglycans are present (postnatal day 21). These findings indicate that cellular cartilage represents an independent kind of supporting tissue, which may serve as a progenitor of hyaline or elastic cartilage ("transitional cellular cartilage") but does not differentiate from hyalin cartilage.

A comparative study of perichondrial tissue in mammalian cartilages.

The general organization, cellular and extracellular components, and structural variation of perichondrium have been studied in different mammalian cartilages by polarized light and transmission electron microscopy. The overall structure is that of a dense connective tissue composed of variable numbers of thin, stratified, closely-packed lamellae, themselves composed of closely-matted collagen fibres running in the plane of the cartilage surface, but oriented at various angles to each other. Variations mainly concern the arrangement of the fibre bundles in the transition zones between perichondrial and cartilage matrices, and between perichondrium and surrounding tissues. Perichondrial cells have the characteristics of fibrocytes. A cambial layer of undifferentiated stem cells was never observed. A layer of 'perichondrial lining cells' with distinctive ultrastructural characteristics was observed in some cartilage units, which separates the perichondrium from the surrounding loose connective tissue. The ultrastructural results demonstrate that the cartilage and perichondrial extracellular matrices are distinct, and what have been designated perichondrial 'transition' and 'proliferative' zones are in fact parts of the most superficial cartilage layer. Variations in perichondrial structure appear to correlate with diversity of cartilage function and we conclude that each cartilage unit plus perichondrium forms a tightly-integrated entity, best regarded as a unitary organ within the skeletal system.

Evaluation of commercially available antibodies to cytokeratin intermediate filaments and laminin in normal cat pinna.

The pattern of distribution of cytokeratin (CK) intermediate filaments can be used to characterize subsets of epithelial tissues. The purpose of the study was to examine the CK expression of feline pinna skin. Six normal feline pinnae were routinely processed in formalin. An immunohistochemical method was used to stain the pinnae with 8 commercially available anti-human CK antibodies (Abs) (PKK1, CAM 5.2, UCD 10/11, 35BH11, 34BE12, AE1/AE3, MAK 6, A575) and an anti-human laminin Ab. All the CK Abs selectively localized to epithelium except 35BH11, which did not react with any part of the pinna. Some epithelial subsets were identified by their unique staining pattern with CK Abs. Basal cells but not suprabasal cells of the epidermis stained with PKK1; basal but not lumenal cells of apocrine glands stained with 34BE12. Apocrine glands stained with all CK Abs except 35BH11. All epithelial structures were stained with A575. Basal lamina of epithelial and mesenchymal tissues was clearly identified by the anti-laminin Ab. The results indicate that in cat pinna some commercially available anti-human CK Abs selectively stain subsets of epithelium and adnexa. PKK1, 34BE12, and A575 were the CK Abs with the most consistent staining patterns, the other Abs stained more variably from pinna to pinna. The pattern of epithelial and adnexal staining was similar but not identical to that reported for humans.

Auditory epithelial migration. II: Morphological evidence for auditory epidermal cell migration in rat.

Morphology of the tympanic membrane (TM) and external auditory canal (EAC) was studied in healthy, intact rat ears. TM-perforated ears (3 days after making the perforation) and TM-perforation-healed ears (14, 28 and 42 days after making the perforation). In intact ears, the epidermis in the annular region of the EAC displayed a characteristic appearance with cytoplasmic protrusions. We termed these protrusions as "finger-like projections". In contrast to the rat, the annular region of the EAC in the guinea-pig did not show "finger-like projections". Following a perforation in the centre of the anterior or the posterior quadrant of the pars tensa in rats the "finger-like projections" disappeared from the annular region on the perforated side of the EAC, while the projections remained on the malleus side of the perforation edge. In perforation-healed ears analysed 42 days after the perforation, the "finger-like projections" had recurred in the annular region on the perforated side of the EAC. The "finger-like projections" are likely to express maturation (keratinization) and desquamation of epidermal cells in the pars tensa and also could constitute morphological evidence of their migration on the TM.

[Electron microscopic observation of the denervated flap reinnervation after implantation of sensory nerve].

Flap reinnervation was studied by electron microscopy in the rabbit cervico-shoulder flap with great auricular nerve implanted. After transferring the flap to the dorsal defect of the rabbit's ear and division of its pedicle, the original nerve fibers of the flap underwent a degenerative process which would persist over 2 months. The great auricular nerve implanted into the flap regenerated axons by entering into old endoneurial rube of the flap and sprouting. The development process of the regenerating nerves showed that the unmyelinated fibers appeared first in the 2nd month, and the myelinated ones in the 4th month. The regenerating nerve fibers had often accompanied by blood vessels.

[Alkaptonuria-ochronosis]. / Alkaptonuria-ochronosis.

The authors describe the case of a 40-year old female patient. Since her childhood she realised of her urine the black discoloration of the underwear. For about a year, without subjective complaints, blue-black color of the skin involved the axillae and pinnae. For a year appeared the increased pain of thoracal and lumbal spine column and the limitation of motion of these parts. The examination of urine, histological and electron microscopical findings, the X-ray photograph of the spinal column confirmed the diagnosis of alkaptonuria or rather congenital ochronosis.

[Pseudocyst of the auricle]. / Pseudoquiste de pabellón auricular.

Reporting one case of pseudocyst of the auricle in a young male, 18, white and wealthy, diagnosed and treated. Bibliographical review of this condition and explanation of its etiopathogenetic, clinic and therapeutical characteristics, as well. This deformity seems to be more prevalent as the number of published cases may suggest.

[Pilomatrixoma of the auricle. Differential diagnosis with carcinoma pilomatrixoma]. / Pilomatrixoma de pabellón auricular. Diagnóstico diferencial con el carcinoma pilomatrixial.

A 34 year-old man, with a two centimeter diameter quickly growing nodule on the auricular pavillion is presented. After mass excision the histologic diagnosis of pilomatrixoma was made. Pilomatrixoma is a rare benign tumor arising on the hair matrix. The differential diagnosis include pilomatrix carcinoma, a locally and recurrent aggressive tumor capable to make pulmonary metastasis. A review of the literature is included, with emphasis on the clinical and histopathological aspects and the therapeutic attitude.

[Adenocarcinoma of the ceruminous glands: report of three cases]. / Adenocarcinoma de glándulas ceruminosas: presentación de tres casos.

We report three cases of ceruminoma seen in our department over a 1-year period and review the neoplasms of the ceruminous glands. According to the Welti classification, our three cases were ceruminous adenocarcinomas. Based on existing literature, ceruminous adenocarcinoma is the least frequent neoplasm of the ceruminous glands.

[The ultrastructural characteristics of the histopathological changes at the site of attachment to the host body of larvae of the ixodid tick Ixodes ricinus]. / Ul'trastrukturnye osobennosti gistopatologicheskikh izmenenii v meste prikreplenii k telu khoziaina lichinok iksodovogo kleshcha Ixodes ricinus.

The attachment of ixodid tick Ixodes ricinus larvae to white mice and histopathology of host tissue in the attachment site were investigated by means of electronic microscopy. It was demonstrated the presence of cement substance around the mouthparts of tick during the first and the second days of feeding period and the absence of it at the last day of this period. The cement substance consists only of the cement cone (the external cement), situated on the surface of host epidermis. The tick mouthparts in the host dermis were surrounded by zone of modified collagene fibers. Examination of feeding site showed the intensive neutrophil migration and the formation of feeding cavity in 2 days after attachment of tick. At the same time the erythrocytes and active fibroblasts were found in the feeding cavity.

[Ultrastructural characteristics of the histopathologic changes at the site of attachment to the host's body of larvae of the ixodid tick Hyalomma asiaticum]. / Ul'trastrukturnye osobennosti gistopatologicheskikh izmenenii v meste prikrepleniia k telu khoziaina lichinok iksodovogo kleshcha Hyalomma asiaticum.

Tissues of white mice in the place of the attachment of H. asiaticum larvae were examined by means of electron microscopy 2, 4, 24 and 72 hours after the attachment to the host. Fine structure of the cement sheath, peculiarities of its connection with host's tissues, fine structure of derm at different feeding stages of the tick are studied.

External and middle ear pathology in TGF-alpha-deficient animals.

Transforming growth factor-alpha (TGF-alpha) is a growth-regulatory peptide found in a wide range of embryonic and adult tissues. TGF-alpha is produced by keratinocytes and has been reported to be overexpressed in several epidermal diseases, including middle ear cholesteatoma. This report describes ear pathology in the waved-1 mutant mouse, which is severely deficient in TGF-alpha. Morphologic changes of the external and middle ear were studied histologically in waved-1 mutants 2 weeks to 6.5 months of age. Abnormalities found in the mutants included epidermal hyperplasia of the external ear canal (EAC) and tympanic membrane (TM) and enlargement of specialized sebaceous glands adjacent to the cartilaginous EAC. Sebum and desquamated keratin progressively accumulated within the EAC, displacing the TM into the middle ear. These changes appear similar to those occurring in Mongolian gerbils, which are known to develop cholesteatoma. The alterations found in waved-1 mutants are discussed in relation to the possible involvement of TGF-alpha in cholesteatoma pathogenesis.

[Structuro-functional organization of human elastic cartilage]. / Strukturno-funktsional'naia organizatsiia élasticheskogo khriashcha cheloveka.

The light- and electron-microscopic investigation performed in order to study the elastic cartilage ultrastructure in the human concha auriculae has demonstrated that a peculiar feature of the later is abundance of elastic fibers both in its perichondrium and in the cartilagenous tissue. In the perichondrium the fibrillar elements (collagenous and elastic fibers) are oriented in parallel with the cartilagenous plate surface. There is not any definite regularity in the arrangement of the fibers of the cartilagenous tissue. As demonstrates the light microscopy, homogeneity of the ground substance is connected with a very compact arrangement of its fibrillar elements. Spaces between the fibers and fibrillae are filled with an amorphous ruthenium-positive substance of the proteoglycane nature.

[Chronic atrophying polychondritis]. / La polychondrite chronique atrophiante.

A case of chronic atrophic polychondritis in a 75 year old female patient is reported. The disease started with an asymptomatic lesion of the nasal septum. It was diagnosed after involvement of the auricular cartilages, which was followed by an ocular and then by a tracheal symptomatology. A histological study by means of optical microscopy and of electronic microscopy is presented. The general characteristics of chronic atrophic polychondritis are given. It is a systemic, inflammatory disease, and progresses by successive outbreaks. Its gravity lies in the frequency of laryngeal and tracheo-bronchial lesions. Its pathogeny is unknown. Two hypotheses are considered: the first, that it is due to a disturbance in the metabolism of mucopolysaccharides ; the second is based on an immunological mechanism.

Ultrastructural visualization of elastic fibres with a tannate--metal salt method.

A modification of the tannic acid-metal salt method was applied as an ultrastructural stain for elastin. Thin sections of glutaraldehyde-fixed, embedded rat aorta and rabbit elastic cartilage, with and without osmication, were examined. Raising the pH of the tannic acid solution from 2.7 to 9.0 progressively increased the electron-density of elastic fibres and collagen fibrils in osmicated and unosmicated specimens. The maximum tannic acid staining of elastic fibres was observed in the pH range 7.0-9.0. Collagen staining, although less intense than that of elastic fibres, was also greatest in this pH range. Elastic fibres in osmicated specimens demonstrated the strongest tannic acid staining with a minimal increase in density of collagen and cell nuclei when compared to the unosmicated specimens. Sequential treatments of osmicated specimens with tannic acid pH 7.0-9.0, and uranyl acetate, pH 4.1, enhanced the density of the elastin intensely, increased collagen staining moderately, but hardly increased the density of nuclei and microfibrils. In elastase-digested osmicated specimens, all tannic acid (pH 7.0)-uranyl acetate-reactive elastin was selectively removed. These results demonstrate that all the neutral and alkaline tannic acid-uranyl acetate methods can be used as a postembedment stain for elastin specimens fixed in glutaraldehyde and osmium tetroxide.

[Ultrastructural manifestations of the secretory function of the chondrocytes in elastic cartilage]. / Ultrastrukturni proiavi na sekretornata funktsiia na khondrotsitite v elastichniia khrushtial.

The authors examined ultrastructural manifestations of the secretory function of chondrocyetes in the auricular tendon of rats. They found that chondrocyetes were active secretorily in the prenatal and early postnatal ontogenesis; in later age such activity possessed mainly those chondrocytes located subperichondricaly. The existance of direct communications of cysternas of the granulated endoplasmic reticulum with extracellular area was interpreted as a possibility for direct release of the secretory products. Small coated vesicules with dense content were followed-up from the Goldi's organs till their openings on the cellular surface. Two types of vacuoles were differentiated-some with optically dense content, localized in the Goldi's organs, and others-optically empty, which were encountered in their boundaries as well. A concept was given that the first type originates from the granulated endoplasmic reticulum and transported protein product, but the second type-from the Goldgi's complex and transported probably polysaccharides.

Electron microscope study of bone lesion in cholesteatoma otitis.

Biopsy specimens were obtained at ear surgery of patients with cholesteatoma otitis and were studied by electron microscopy. The osseous tissue decalcified in EDTA demonstrated degradation of collagen matrix as well as extensive degeneration of bone cells. The surface of the eroded bone was found to be in direct contact with the subepithelial connective tissue or the granulation, but not with the keratinizing squamous epithelium of matrix. These results indicate that the bone destruction by cholesteatoma is of non-osteoclastic type and lend support to the view that the keratinizing squamous epithelium do not participate in bone destruction. One the ultrastructural basis, the inflammatory process in the soft tissue adjacent to bone and extensive degeneration of bone cells are considered as cardinal factors for bone destruction in this disease.