Distinguishing androgenetic alopecia from chronic telogen effluvium when associated in the same patient: a simple noninvasive method

BACKGROUND: Distinguishing chronic telogen effluvium (CTE) from androgenetic alopecia (AGA) may be difficult especially when associated in the same patient. OBSERVATIONS: One hundred consecutive patients with hair loss who were clinically diagnosed as having CTE, AGA, AGA + CTE, or remitting CTE. Patients washed their hair in the sink in a standardized way. All shed hairs were counted and divided "blindly" into 5 cm or longer, intermediate length (>3 to <5 cm), and 3 cm or shorter. The latter were considered telogen vellus hairs, and patients having at least 10% of them were classified as having AGA. We assumed that patients shedding 200 hairs or more had CTE. The kappa statistic revealed, however, that the best concordance between clinical and numerical diagnosis (kappa = 0.527) was obtained by setting the cutoff shedding value at 100 hairs or more. Of the 100 patients, 18 with 10% or more of hairs that were 3 cm or shorter and who shed fewer than 100 hairs were diagnosed as having AGA; 34 with fewer than 10% of hairs that were 3 cm or shorter and who shed at least 100 hairs were diagnosed as having CTE; 34 with 10% or more of hairs that were 3 cm or shorter and who shed at least 100 hairs were diagnosed as having AGA + CTE; and 14 with fewer than 10% of hairs that were 3 cm or shorter and who shed fewer than 100 hairs were diagnosed as having CTE in remission. CONCLUSION: This method is simple, noninvasive, and suitable for office evaluation.     

Disseminated porokeratosis with fatal metastatic squamous cell carcinoma: an additional case of "malignant disseminated porokeratosis"

We report on a patient with a disseminated form of porokeratosis in whom bowenoid lesions and squamous cell carcinoma developed in an apparent sequential progression. Local and disseminated metastases ensued, resulting in the death of the patient. Furthermore, we found an overexpression of the p53 protein in the keratinocytes beneath and adjacent to the cornoid lamella in the porokeratotic lesion and throughout the epidermis in a bowenoid lesion. Although malignancy has been reported previously in various types of porokeratosis, the development of fatal metastatic squamous cell carcinoma in the setting of this disease is a rare event. The histopathologic findings of this case document the association of porokeratotic lesions with bowenoid dysplasia and aggressive squamous cell carcinoma and confirm that a p53 functional aberration can be important in a malignant outcome such as this.     

Interface connections of a transmembrane voltage sensor

Voltage-sensitive ion channels open and close in response to changes in transmembrane (TM) potential caused by the motion of the S4 voltage sensors. These sensors are alpha-helices that include four or more positively charged amino acids, most commonly arginine. The so-called paddle model, based on the high-resolution structure of the KvAP K+ channel [Jiang, et al. (2003) Nature 423, 33-41], posits that the S4 sensors move within the membrane bilayer in response to TM voltage changes. Direct exposure of S4 sensors to lipid is contrary to the classical expectation that the dielectric contrast between the membrane hydrocarbon core and water presents an insurmountable energetic penalty to burial of electric charges. Nevertheless, recent experiments have shown that a helix with the sequence of KvAP S4 can be inserted across the endoplasmic reticulum membrane. To reconcile this result with the classical energetics argument, we have carried out a molecular dynamics simulation of an isolated TM S4 helix in a lipid bilayer. The simulation reveals a stabilizing hydrogen-bonded network of water and lipid phosphates around the arginines that reduces the effective thickness of the bilayer hydrocarbon core to approximately 10 A in the vicinity of the helix. It suggests that bilayer phospholipids can adapt locally to strongly perturbing protein elements, causing the phospholipids to become a structural extension of the protein.     

Angioarchitectural Evolution of Clival Dural Arteriovenous Fistulas in Two Patients

Dural arteriovenous fistulas (dAVFs) may present in a variety of ways, including as carotid-cavernous sinus fistulas. The ophthalmologic sequelae of carotid-cavernous sinus fistulas are known and recognizable, but less commonly seen is the rare clival fistula. Clival dAVFs may have a variety of potential anatomical configurations but are defined by the involvement of the venous plexus just overlying the bony clivus. Here we present two cases of clival dAVFs that most likely evolved from carotid-cavernous sinus fistulas.Key Words: Neuro-ophthalmology, Carotid-cavernous sinus fistula, Clivus, Clival fistula, Dural arteriovenous fistula