Scanning Electron Microscopy of the Inner and Outer Aspects of Tiger Tail Hairs.

Background: Tiger tail hairs, Morse hairs or pili annulati is a nonsyndromic hair shaft disorder, characterized by alternating light and dark bands along the hair shaft. Methods: The outer surface and the inner structure of longitudinally cut tiger tail hairs were examined with scanning electron microscopy. Results: Hair specimens of five affected individuals showed small surface undulations with "curtain-like" folding of the hair cuticula (microcanaliculi). In the inner surface cord-like linear structures with serpiginous, tortuous traject were seen, associated with some cavities. Conclusions: These findings suggest that this condition is due to some deficient protein synthesis/arrangement, not only due to cavities in the hair cortex. The term Tiger tail hair is a descriptive clinical term of little scientific rigor. This disorder has been reported mainly as pili annulati; however, rings are not observed. In analogy to pili canaliculi, in which well-formed grooving is observed in the hair surface, we suggest the term pili microcanaliculi to describe this condition, based in the ultrastructural findings.

Pitted keratolysis.

Pitted keratolysis is a skin disorder that affects the stratum corneum of the plantar surface and is caused by Gram-positive bacteria. A 30-year-old male presented with small punched-out lesions on the plantar surface. A superficial shaving was carried out for scanning electron microscopy. Hypokeratosis was noted on the plantar skin and in the acrosyringium, where the normal elimination of corneocytes was not seen. At higher magnification (x 3,500) bacteria were easily found on the surface and the described transversal bacterial septation was observed.

Isoflavone aglycone content and the thermal, functional, and structural properties of soy protein isolates prepared from hydrothermally treated soybeans.

UNLABELLED: Soybeans were hydrothermally treated at 2 different temperatures (40 °C and 60 °C) and for 4 different hydration times (4, 8, 12, and 16 h) to (i) increase the isoflavone aglycone content in a soy protein isolate and (ii) evaluate the changes in thermal, functional, and structural properties of a soy protein isolate as a function of hydrothermal treatment conditions. Our study is the first to evaluate aglycone content, extraction yield, ß-glucosidase activity, differential scanning calorimetry, protein digestibility, scanning electron microscopy, water absorption capacity (WAC), foaming capacity (FC), and foaming stability of soy protein isolates prepared from hydrothermally treated soybeans. For aglycone enhancement and the extraction yield maintenance of soy protein isolates, the condition of 40 °C for 12 h was the best soybean hydrothermal treatment. The structural rearrangement of proteins that occurred with the hydrothermal treatment most likely promoted the capacity of proteins to bind to aglycone. Moreover, the structure shape and size of soy protein isolates verified by scanning electron microscopy appears to be related to the formation of hydrophobic surfaces and hydrophobic zones at 40 °C and 60 °C, respectively, affecting the protein digestibility, WAC, and FC of soy protein isolates. PRACTICAL APPLICATION: The aglycone content in the soy protein isolate can be improved with the hydrothermal treatment of soybeans. The temperature and time used for hydrothermal treatment must be selected in order to achieve a soy protein isolate with high aglycone content, extraction yield, and functionality. This technology is suitable for providing healthier soy protein isolates for food industry with improved functional and structural properties.

Ecthyma-like phaeohyphomycosis caused by Cladosporium cladosporioides.

A case of cutaneous phaeohyphomycosis caused by Cladosporium cladosporioides in a 50-year-old housewife is described. The clinical presentation was an ecthyma-like crusted lesion on the back of her left hand. Scanning electron microscopy of the culture showed the conidiophores and the limoniform or ellipsoidal conidia, with a slightly verrucous surface. The lesion was removed surgically, with no relapses after 6-month follow up.

Ichthyosis cribriformis: A new entity?

A 22-year-old woman had an unusual congenital skin disorder in the form of ichthyosis characterized by innumerable keratotic plugs, resulting in a peculiar sievelike appearance. On histopathologic examination the epidermis showed a pronounced orthohyperkeratosis. The keratotic plugs seemed to emerge from the infundibular region of hair follicles. Immunohistochemical characterization revealed a normal keratin and filaggrin expression. Oral treatment with isotretinoin resulted in a reduction of the hyperkeratosis. Because we could not find any previously reported similar case, we propose the new name "ichthyosis cribriformis," which means "sievelike ichthyosis."

Elastic tissue damage in cephalic acquired cutis laxa.

Cutis laxa is a rare condition characterized by diminished elastic tissue. We report the histological changes from a 22-year-old male patient, who presented since 4 years hanging and inelastic facial skin, giving him an older appearance. The palpebral, preauricular and submandibular skin obtained after a facelift were examined. Conventional light microscopy with hematoxylin-eosin staining showed perivascular lymphocytic infiltrates and crossed-over collagen fibers. With Weigert staining, a lessening of elastic fibers with fragmentation, shortening and clumping was seen. The oxytalanic fibers in the papillary dermis were also affected, ranging from absence or reduction to flattening with clumping of the fibers, giving an irregular contour to the basal membrane zone. These findings were more intense in the palpebral skin. Transmission electronic microscopy showed reduction of the elastic fibers, a granular degeneration of the elastic tissue was found and collagen fibers were normal. Similar to light microscopy, at the ultrastructural level, the basal membrane has an irregular contour.