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

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*

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

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

A 41 year-old man had dark pigmented papules and plaques, 4 to 15 mm in size, on the proximal portion of the dorsum of the penile shaft and pubic area of 8 months duration. Over next several months, flesh colored, macerated papules, 2 to 4 mm in size, appeared on the left side of the scrotum Light microscopic examination from a pigmented lesion of the penile shaft showed typical findings of Bowen's disease. Ultrastructural findings included: widening of intercellular space, a decrease in the number of desmosomes with microvillous projections, aggregation of tonofilaments, an increase in the mitotic keratinocytes, an increase in the number of melanin granules, and disorganized bundles of tonofilaments surrounding chromosomes. Virus-like particles were not observed. Based on the ultrastructural findings and review of literatures, it seems to be probable that bowenoid papulosis is a clinical variant of Bowens disease.
Adult ; Bowen's Disease ; Desmosomes ; Extracellular Space ; Genitalia* ; Humans ; Intermediate Filaments ; Keratinocytes ; Melanins ; Scrotum

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: Desmocollins (Dsc) are calcium-dependent transmembrane glycoproteins of desmosomes that are important in the junction complex of epidermis and maintain structural integrity of the skin from external stressors. Among three Dscs (Dsc 1, 2, 3), Dsc 1 and 3 are distributed on skin. OBJECTIVE: The purpose of this study was to observe the Dsc 1 distribution pattern on the skin and oral mucosa during fetal development. METHODS: Skin was obtained from the sole and scalp of 33 fetuses, ranging from 10 to 37 weeks of gestational age. Immunohistochemical staining was performed on the paraffin-embedded tissue using a Dsc 1 monoclonal antibody. RESULTS: Dsc 1 was expressed in the suprabasal layer but not in the basal layer of the epidermis of the sole at the 10th week of gestation. Thereafter, Dsc 1 expression further increased in the suprabasal layer with initiation of stratification and increased gradually in the granular layers of the sole and scalp epidermis. Dsc 1 was strongly expressed in the superficial layer of the infundibulum and inner root sheath of the hair follicle but was not expressed in the sebaceous cells or other hair components. The eccrine duct epithelium was focally and weakly positive for Dsc 1 expression. Furthermore, Dsc 1 was not expressed in oral mucosa, although the oro-cutaneous portion was strongly expressed in the superficial layer. CONCLUSION: Dsc 1 was strongly expressed in the suprabasal cells of the epidermis during fetal skin development, and expression increased gradually in the granular layer and inner root sheath of the hair follicle. However, Dsc 1 was not expressed in basal cells or in oral mucosa. Dsc 1 may play a role in the maintenance of epithelial integrity as part of desmosomes.
Desmocollins ; Desmosomes ; Epidermis ; Epithelium ; Fetus ; Gestational Age ; Glycoproteins ; Hair ; Hair Follicle ; Mouth Mucosa ; Pregnancy ; Scalp ; Skin

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

Our aim was to identify histologic changes in cervical carcinoma tumor cells due to chemotherapy,by electron microscopic examination. Cisplatin and 5-fluorouracil were used between March 1, 1994 and February 28, 1995 on a total of 16 patients. The treatment schedule consisted of 75 mg/m2 cisplatin via iv with hyperhydration on Day 1, in combination with 1000 mg/m2 5-fluorouracil via continuous iv on Day 1 to 5. The treatment was repeated every 4 weeks with a maxinum of 3 courses. Ultrastructurally, chemotherapy induced apoptosis,indicated by condensation of nucleus and cytoplasm,fragmentation of nuclei, and apoptotic bodies. Due to repeat chemotherapy, increased levels of desmosomes were noted and parts of tumor nests were replaced by mature squamous cells. Tumor nests were reduced in size, mitochondria exhibited swelling, the endoplasmic reticulum was dilated, and infiltration of inflammatory cells increased after chemotherapy. These results suggest that chemotherapy induces apoptosis and injury to the cytoplasm and nuclei of tumor cells. However, the exact selection mechanism of the biochemical pathway of cell death is not fuUy understood. Further study of the molecular biologic actions of cell death after chemotherapy is warranted.
Apoptosis ; Appointments and Schedules ; Cell Death ; Cisplatin ; Cytoplasm ; Desmosomes ; Drug Therapy* ; Endoplasmic Reticulum ; Fluorouracil ; Humans ; Mitochondrial Size