Sarcomatoid renal cell carcinoma is an uncommon tumor that has to be distinguished from renal carcinosarcoma. We have described three cases of sarcomatoid renal cell carcinoma showing different clinical and light microscopic features. An ultrastructural study of the tumor cells from the sarcomatoid area revealed frequent desmosomal junction, confirming the epithelial nature of the neoplasm. All three cases showed an aggressive clinical course and tended to invade adjacent organs or tissues. We believe that an histological and immunohistochemical examination in conjunction with an electron microscopic examination are necessary to diagnose sarcomatoid renal cell carcinoma.
Carcinoma, Renal Cell* ; Carcinosarcoma* ; Desmosomes ; Microscopy, Electron

Accurnulation of keratinized cells within the infundibulum of pilosebaceous canal is important in the pathogenesis of acne. Light and electron microscopic study of experimentally induced comedones, from the rabbit's external ear canal, was performed to define the earIy morphologic changes within and around the epithelial lining of the comedones. In light microscopic observation, early comedone was composed of loose cohesive horny cells and late comedone was composed of a mixture of loose and tight cohcsive horny cells. Cohesion between horny cells occured, in eIectron microscopic study, in two different ways: initially, by the persistence of desmosomes; later, and to a lesser extent, by tight junctions, which tightly bound the horny cells together. Multiple lipid droplets within the horny ceIls and a gradual decrease in the numbrane coating granules were observed.
Acne Vulgaris ; Desmosomes ; Ear Canal ; Tight Junctions

We have observed the ultrastructures of Langerhans cell in the normal limbal eonjunctiva by electron microscopy and expression of HLA-DR antigen by peroxidase-antiperoxidase(PAP) method in the normal limbal conjunctiva. In electron microscope, Langerhans cell had no junctional complex like desmosome, irregular and invaginated nucleus, and characteristic Birbeck granlues in the cytoplasm. In PAP method, HLA-DR-positive cells were found in basal or suprabasal layer of conjunctival epithelium as dendritic form.
Conjunctiva* ; Cytoplasm ; Desmosomes ; Epithelium ; HLA-DR Antigens* ; Microscopy, Electron

Well-differentiated papillary mesothelioma (WDPM) of the peritoneum is considered to be a distinct subtype of peritoneal mesothelioma and has mostly behaved in a benign fashion. We report a case of WDPM in a 48-year-old-woman. It was incidentally found during a hysterectomy for a uterine cervical carcinoma. Grossly, the tumor was composed of multiple peritoneal nodules, measuring up to 2 cm. Microscopically, the nodules showed well-developed papillae lined by a single layer of cuboidal mesothelial cells. Immunohistochemical staining revealed a positive reaction for cytokeratin and a negative reacion for carcinoembryonic antigen and Leu-M1. Ultrastructurally, the tumor cells showed numerous long, slender microvilli and desmosomes.
Carcinoembryonic Antigen ; Desmosomes ; Hysterectomy ; Keratins ; Mesothelioma* ; Microvilli ; Peritoneum*

BACKGROUND: Matrix metalloproteinases (MMPs) participate in extracellular matrix degradation and may play an important role in basal membrane damage in many dermatologic diseases. Recent studies implicated the importance of MMP-9 in the pathogenesis of bulla formation of bullous pemphigoid (BP). Various autoimmune bullous diseases are strongly associated with desmosome or hemidesmosome pathologies, and show an increased level of lesional MMP and exposed autoantigens from these structures. OBJECTIVE: This study evaluated the level of MMP-2, -3, and -9 in three types of autoimmune bullous disease [BP, pemphigus vulgaris (PV), pemphigus foliaceus (PF)] with the aim of investigating the role of MMPs in the pathogenesis of autoimmune bullous diseases. METHODS: Sample specimens were obtained from skin lesions of patients with BP (n=12), PV (n=10), and PF (n=12), and from normal controls (n=8). The immunohistochemical expression of MMP-2, -3, and -9 was analyzed and serum levels of MMP-2, -3, and -9 were measured by enzyme-linked immunosorbant assay (ELISA). The results were analyzed with reference to graded levels of clinical severity. RESULTS: Expression of dermal MMP-2, -3, and -9 were increased in BP, PV, and PF (p=0.036, 0.022, and 0.015, respectively). However, decreased expression of the three MMPs in the epidermis of skin lesions may have resulted from epidermal destruction. ELISA-determined serum levels of MMP-2, -3, and -9 increased in BP, PV and PF. Interestingly, MMP-2 was significantly increased in the sera of BP patients (p=0.015), consistent with the previous studies concerning the role of gelatinase (MMP-2 and -9) in the pathogenesis of BP. In BP patients, clinical severity was proportional to increased levels of MMP-2 in both skin lesions and and sera. CONCLUSION: The increased expression of MMP-2, -3, and -9 in skin lesions and sera may reflect the involvement of these enzymes in the mechanism of bulla formation in autoimmune bullous diseases including BP. In addition, expression of MMP and clinical severity may be closely connected.
Autoantigens ; Blister ; Desmosomes ; Epidermis ; Extracellular Matrix ; Gelatinases ; Hemidesmosomes ; Humans ; Matrix Metalloproteinases ; Membranes ; Pemphigoid, Bullous ; Pemphigus ; Skin

A 25-year-old man with familial benign chronic pemphigus presented with a one-year history of a localized pruritic recurrent eruption on his perianal area, Physical examination showed moist, macerated, fissured and scaly patches on erythematous base, A biopsy specimen showed extensive intraepidermal separation containing acantholytic cells. Electron microscopic observation showed widened intercellular space, detachment of the tonofilaments from the desmosomes, and subsequent concentration of the tono filaments around the nucleus. Microvilli were elorigated, thinned and branehed. 1)esmosomes were reduced in number. This case is unique in its clinical location, showing no family tendency.
Adult ; Biopsy ; Desmosomes ; Extracellular Space ; Humans ; Intermediate Filaments ; Microvilli ; Pemphigus, Benign Familial* ; Physical Examination

BACKGROUND: Bentonite clay, which is a major component of mud pack, has been used for various purposes in cosmetics. Glycolic acid is known to be effective in the treatment of acne. Al-though those products are used widely, information on the mode of action and effects on the skin are little and controversial till now. OBJECTIVE: To investigate whether bentonite alone, or bentonite with glycolic acid in mixed formulation affect the stratum corneum leading to alteration on cutaneous barrier function and whether those products alter the lipid lamellae and desmosomes of corneocytes. MATERIALS AND METHODS: Mud pack-type ointment of bentonite, bentonite and 5% glycolic acid formulation, bentonite and 10% glycolic acid formulation were applied on the volar fore-arm of the five healthy men and flank skin of five 6-8 week old hairless mice. Transepidermal water loss and capacitance were measured. Electron microscopic examination after ruthenium tetroxide postfixation was performed on the flank skin of the mice. RESULTS: Transepidermal water loss(TEWL) increased immediately and normalized 4 to 6 hours later after removal of vapor permeable membrane in both mouse and human. Capacitance did not show any evidence of change in the water content of the stratum corneum. Electron microscopic examination revealed that lipid lamellae and desmosome of corneocytes were not de-graded, but lamellar body secretion and partially electron-lucent material was-increased in 10% glycolic acid and bentonite mixture-treated area. CONCLUSION: Barrier function of stratum corneum is not disturbed by bentonite and glycolic acid formulations at the concentration used. Barrier structures are not disrupted, but lamellar body secretion and partially electron-lucent material was increased by bentonite and glycolic acid formulations at higher concentration.
Acne Vulgaris ; Animals ; Bentonite* ; Desmosomes ; Humans ; Male ; Membranes ; Mice ; Mice, Hairless ; Mud Therapy ; Ruthenium ; Skin ; Water

Osteofibrous dysplasia (OFD)-like adamantinoma is a rare skeletal tumor that is characterized by the predominant OFD-like pattern with scattered epithelial nests. Adamantinoma shares clinical features (the majority of lesions in the tibia and the prevalent age group), radiologic findings (radiolucency with sclerotic shadow), and pathologic similarities (particularly the presence of scattered cytokeratin-positive stromal cells) with OFD. We describe a case of OFD-like adamantinoma. Epithelial cell nests express the epithelial membrane antigen, pancytokeratin, CK14, and collagen type IV. Ultrastructurally, the oval to spindle cells in the epithelial foci had abundant tonofilaments, and well-formed desmosomes with dense plaques, of which well preserved desmosomes are demonstrated for the first time in OFD-like adamantinoma. These immunohistochemical and ultrastructural findings further support that the origin of epithelial cells of classic and OFD-like adamantinoma are epithelial cells transformed from fibroblastic cells in the proliferating osteofibrous tissue.
Adamantinoma* ; Collagen Type IV ; Desmosomes ; Epithelial Cells ; Fibroblasts ; Fibroma, Ossifying ; Immunohistochemistry ; Intermediate Filaments ; Mucin-1 ; Tibia

A case of hypertrophic lichen planus was reported and the literature reviewed. A 69-year-old widowed woman displayed generaIized discrete, multiple, round, various sized, flat-topped, hypertrophied papules and nodules on the abdomen, trunk and four extrimies for 42 years. An electron microscopic finding revealed widespread breakdown and thickening of the basal lamina at the dermo-epidermal junction and a degenerating change of the desmosomes. No particular intran uclear particles or bodies were discovered. We suggest that emotional factors and autoimmune mechanism might be the cause of the eruption in this case.
Abdomen ; Aged ; Basement Membrane ; Desmosomes ; Female ; Humans ; Lichen Planus* ; Lichens* ; Widowhood

BACKGROUND: Moisturizers induce skin hydration and then increase flexibility and elasticity, making the skin soft and smooth, and protecting it against environmental stimuli. OBJECTIVE: The aim of this work was to study the role of intercorneocyte lipid layers and desmosomes in the mechanism of moisturization. METHODS: Transepidermal water loss (TEWL) and capacitance were measured and the morphologic changes of the intercorneocyte lipid layers and desmosomes with electron microscopy, using ruthenium tetroxide (RuO4) postfixation, following the application of glycerin, propylene glycol, and a mixture of glycerin and propylene glycol for a 2 hour period to the epidermis of hairless mice were measured. RESULTS: 1. The TEWL was significantly increased in all three groups; glycerin, propylene glycol, and mixture of glycerin and propylene glycol. The increase of TEWL after the application of glycerin was maintained from the second to the forth hour after application which was statistically significant, after the application of propylene glycol it was maintained for 5 hours, and after the application of a mixture of glycerin and propylene glycol, for 6 hours. 2. The capacitance also was increased in all three experimental groups, compared to the control group. However there was no statistical significance. 3. Light microscopic findings showed no specific changes in all three groups, compared to the control group. 4. Ultrastructural observation by electron microscope, using RuO4 postfixation, showed widening of the intercorneocyte lipid layers in all three groups. In contrast to glycerin in which the results showed detachment of the desmosomes without changes in the intercorneocyte lipid layers, propylene glycol showed interruption and undulation of the intercorneocyte lipid layers and expansion of the lacunae spaces. A mixture of glycerin and propylene glycol showed interruption and undulation of the intercorneocyte lipid layers, detachment of the desmosomes, and, partial, formation of lacunae. CONCLUSION: These results suggest that the moisturizing effects of glycerin result from an increased detachment of the desmosomes and widening of the intercorneocyte lipid layers and then an increase in the water holding capacity of the stratum corneum. Propylene glycol, a chemical penetration enhancer, induce widening, interruption, and undulation of the lipid layers and expansion of the lacunae space. In the mixture of glycerin and propylene glycol, propylene glycol potentiate and continue the moisturizing effects of the glycerin.
Animals ; Desmosomes* ; Elasticity ; Epidermis ; Glycerol* ; Mice ; Mice, Hairless ; Microscopy, Electron ; Pliability ; Propylene Glycol* ; Ruthenium ; Skin