Description: Extramammary Paget's disease (EMPD) is a rare malignant tumour characterised by erythematous scaly patches or plaques occurring in apocrine gland-bearing skin such as the vulva, penis, scrotum, perineum, perianal area, and axilla. Because of its nonspecific clinical presentation and low incidence, EMPD can be a challenge to diagnose. Therefore, its misdiagnosis as an inflammatory or infectious skin condition (eczema, psoriasis, or candidiasis) is common, and EMPD lesions may worsen before appropriate treatment is initiated. 1,2 Early diagnosis and treatment of EMPD is crucial for a favourable prognosis because a delayed diagnosis can result in a more extensive lesion, dermal invasion, or distant metastasis. Although the utility of dermoscopy has been reported for various pigmented and nonpigmented tumours, 3-7 the dermoscopic patterns of EMPD have rarely been reported in the literature. 8,9 Investigation of clinical and dermoscopic patterns of EMPD could elucidate further characteristics of this rare tumour. This article is protected by copyright. All rights reserved.

Description: Laser and photocell quantum heat engines (QHEs) are powered by thermal light and governed by the laws of quantum thermodynamics. To appreciate the deep connection between quantum mechanics and thermodynamics we need only recall that in 1901 Planck introduced the quantum of action to calculate the entropy of thermal light, and in 1905 Einstein’s studies of the entropy of thermal light led him to introduce the photon. Then in 1917, he discovered stimulated emission by using detailed balance arguments. Half a century later, Scovil and Schulz-DuBois applied detailed balance ideas to show that maser photons were produced with Carnot quantum efficiency (see Fig. 1A). Furthermore, Shockley and Quiesser invoked detailed balance to obtain the efficiency of a photocell illuminated by “hot” thermal light (see Fig. 2A). To understand this detailed balance limit, we note that in the QHE, the incident light excites electrons, which can then deliver useful work to a load. However, the efficiency is limited by radiative recombination in which the excited electrons are returned to the ground state. But it has been proven that radiatively induced quantum coherence can break detailed balance and yield lasing without inversion. Here we show that noise-induced coherence enables us to break detailed balance and get more power out of a laser or photocell QHE. Surprisingly, this coherence can be induced by the same noisy (thermal) emission and absorption processes that drive the QHE (see Fig. 3A). Furthermore, this noise-induced coherence can be robust against environmental decoherence.pnas;108/37/15097/F1F1F1Fig. 1.(A) Schematic of a laser pumped by hot photons at temperature Th (energy source, blue) and by cold photons at temperature Tc (entropy sink, red). The laser emits photons (green) such that at threshold the laser photon energy and pump photon energy is related by Carnot efficiency (4). (B) Schematic of atoms inside the cavity. Lower level b is coupled to the excited states a and β. The laser power is governed by the average number of hot and cold thermal photons, and . (C) Same as B but lower b level is replaced by two states b1 and b2, which can double the power when there is coherence between the levels.pnas;108/37/15097/F2F2F2Fig. 2.(A) Schematic of a photocell consisting of quantum dots sandwiched between p and n doped semiconductors. Open circuit voltage and solar photon energy ℏνh are related by the Carnot efficiency factor where Tc is the ambient and Th is the solar temperature. (B) Schematic of a quantum dot solar cell in which state b is coupled to a via, e.g., solar radiation and coupled to the valence band reservoir state β via optical phonons. The electrons in conduction band reservoir state α pass to state β via an external circuit, which contains the load. (C) Same as B but lower level b is replaced by two states b1 and b2, and when coherently prepared can double the output power.pnas;108/37/15097/F3F3F3Fig. 3.(A) Photocell current j = Γραα (laser photon flux Pl/ℏνl) (in arbitrary units) generated by the photovoltaic cell QHE (laser QHE) of Fig. 1C (Fig. 2C) as a function of maximum work (in electron volts) done by electron (laser photon) Eα - Eβ + kTc log(ραα/ρββ) with full (red line), partial (brown line), and no quantum interference (blue line). (B) Power of a photocell of Fig. 2C as a function of voltage for different decoherence rates , 100γ1c. Upper curve indicates power acquired from the sun.

Description: Background:  Dermatoscopy is a non-invasive technique that can be helpful in the diagnosis of pigmented and non-pigmented skin tumours. The dermatoscopic evaluation of Bowen’s disease (BD) improves diagnostic accuracy. Objective:  To evaluate the usefulness of dermatoscopy as a tool to assess responses to therapy and recurrence of BD. Methods:  Patients with histopathologically diagnosed BD were prospectively enrolled. In all lesions, 3 months after the end of treatment (photodynamic therapy or 5% imiquimod cream), dermatoscopic and histopathological examinations were repeated to evaluate and correlate changes in dermatoscopic features and histopathological results. Cured lesions were monitored using dermatoscopy during the follow-up period. Results:  A total of 23 patients with 29 histopathologically diagnosed BD lesions were included in this study. After treatment, dermatoscopic examination revealed the disappearance of pre-existing vascular structures in 16 lesions, and remaining vascular structures in 13 lesions. Histopathological evaluation of the treated lesions showed remnant intraepithelial neoplasms and increased dermal vascularity in lesions with persistent dermatoscopic vascular structures. However, normal epidermis and decreased dermal vascularity were observed in all but 1 of the lesions without previous dermatoscopic vascular structures. During the follow-up period, 1 lesion showed reappearance of previous vascular structures on dermatoscopy at 9 months after treatment. Histopathological examination confirmed the recurrence of BD. Conclusions:  Our study results demonstrate that the persistence of dermatoscopic vascular structures of BD appears to be associated with residual disease, and disappearance of vascular structures suggests that the disease has been cured. In addition, reappearance of previous dermatoscopic vascular structures indicates the recurrence of BD. Therefore, we suggest that dermatoscopy can be a useful, reliable, and non-invasive tool in the therapeutic follow-up of BD.

Description: Background Subungual haemorrhages are characterised by well-circumscribed dots or blotches with a red to red-black pigmentation, but some cases can be difficult to distinguish from subungual melanoma by the naked eye alone. Dermoscopy has proven to be a useful, noninvasive tool in the diagnosis of pigmented lesions in the nail; however, few dermoscopic studies for subungual haemorrhages have been reported. Objective The purpose of this study was to investigate characteristic dermoscopic patterns of subungual haemorrhage and to find distinctive features that can differentiate subungual haemorrhages from nail unit melanomas. Methods Patients with a confirmed diagnosis of either subungual haemorrhage or nail unit melanoma at a tertiary university hospital were included in the study. Clinical features and dermoscopic patterns were evaluated. Results Sixty-four patients with a total of 90 lesions of subungual haemorrhage were enrolled in the study. The majority of cases (84.4%) showed a combination of more than 1 colour, while 15.6% had only 1 colour. The most common colour of the subungual haemorrhages was purple-black in 36.7% cases. A homogenous pattern was observed in 92.2% cases, globular patterns in 42.2%, and streaks in 38.9%. Peripheral fading and periungual haemorrhages were found in 54.4% and 22.3%, respectively. Destruction or dystrophy of the nail plate was observed in 15.6% cases. In the 16 cases with nail unit melanomas, Hutchinson sign, longitudinal irregular bands or lines, triangular shape of bands, vascular pattern, and ulcerations were found in 100%, 81.25%, 25%, 6.25%, and 81.25% cases, respectively. In contrast, these features were not found in subungual haemorrhages. Conclusions Dermoscopy provides valuable information for the diagnosis of subungual haemorrhage and aids in the differential diagnosis from nail unit melanoma.

Description: PERK inhibits DNA replication during the Unfolded Protein Response via Claspin and Chk1 Oncogene 36, 678 (2 February 2017). doi:10.1038/onc.2016.239 Authors: E Cabrera, S Hernández-Pérez, S Koundrioukoff, M Debatisse, D Kim, M B Smolka, R Freire & D A Gillespie