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The article offers information on the 2015 World Congress of Dermatology (WCD) to be held in Vancouver, British Columbia in June 2015 on topics including new treatments techniques for skin diseases, clinical practice guidelines to dermatologists and patient care.

Abstract: The autofluorescence properties of normal human skin in the near-infrared (NIR) spectral range were studied using Monte Carlo simulation. The light-tissue interactions including scattering, absorption and anisotropy propagation of the regenerated autofluorescence photons in the skin tissue were taken into account in the theoretical modeling. Skin was represented as a turbid seven-layered medium. To facilitate the simulation, ex vivo NIR autofluorescence spectra and images from different skin layers were measured from frozen skin vertical sections to define the intrinsic fluorescence properties. Monte Carlo simulation was then used to study how the intrinsic fluorescence spectra were distorted by the tissue reabsorption and scattering during in vivo measurements. We found that the reconstructed model skin spectra were in good agreement with the measured in vivo skin spectra from the same anatomical site as the ex vivo tissue sections, demonstrating the usefulness of this modeling. We also found that difference exists over the melanin fluorescent wavelength range (880–910nm) between the simulated spectrum and the measured in vivo skin spectrum from a different anatomical site. This difference suggests that melanin contents may affect in vivo skin autofluorescence properties, which deserves further investigation. [Copyright &y& Elsevier]

Abstract: Melanin content and distribution in skin were studied by examining a patient with white, brown and blue skin tones expressed on skin affected by vitiligo. Both diffuse reflectance and autofluorescence spectra of the three distinction skin sites were measured and compared. Monte Carlo simulations were then performed to help explain the measured spectral differences. The modeling is based on a six-layer skin optical model established from published skin optical parameters and by adding melanin content into different locations in the model skin. Both the reflectance and fluorescence spectra calculated by Monte Carlo (MC) simulation were approximately in agreement with experimental results. The study suggests that: (1) trichrome vitiligo skin may be an ideal in vivo model for studying the effect of skin melanin content and distribution on skin spectroscopy properties. (2) Based on the skin optical model and MC simulation, the content and distribution of melanin in skin, or other component of skin could be simulated and predicted. (3) Both reflectance and fluorescence spectra provided information about superficial skin structures but fluorescence spectra are capable of providing information from deeper cutaneous structures. (4) The research method, including the spectral ratio method, the method of adding and modifying the melanin content in skin optical models, and MC simulation could be applied in other non-invasive optical studies of the skin. [Copyright &y& Elsevier]

Alopecia areata is regarded as a tissue-restricted autoimmune disease of hair follicles in which follicular activity is arrested because of the continued activity of lymphocytic infiltrates. Actual loss of hair follicles does not occur, even in hairless lesions. A variety of immunomodulating therapies, including contact sensitizers and immunomodulators, are part of the usual armamentarium for this disorder. None of these treatments have been consistent in their efficacy, and many have untoward side effects. Nevertheless, their uses in valid animal models provide a tool to dissect out molecular mechanisms of therapeutic effects. For several decades, both mechlorethamine (for the treatment of cutaneous T cell lymphoma) and anthralin (for the treatment of psoriasis) have been used successfully. When these therapies were tested in rat and mouse alopecia areata models, we found anthralin and mechlorethamine to be the most effective topical modalities, respectively. The underlying cellular mechanisms may act through targeting infiltrative lymphocytes, and the molecular mechanisms may involve specific cytokine expression changes. These visible, accessible, and unilaterally treated animal model systems are ideal for studying novel alopecia areata therapies, particularly in terms of their in vivo molecular mechanisms of action. [ABSTRACT FROM AUTHOR]

Evaluates the regenerative capacity of transversely sectioned hair follicle in athymic nude mice. Occipital areas of patients undergoing hair transplantation; Histologic features of hair follicle; Causes of low successful regeneration rate.

Abstract: Quantification of surface roughness greater than a micron is desirable for many industrial and biomedical applications. Polychromatic speckle contrast has been shown theoretically to be able to detect such roughness range using an appropriate light source with a Gaussian spectral shape. In this paper, we extend the theory to arbitrary spectral profile by formulating speckle contrast as a function of spectral profile, surface roughness, and the geometry of speckle formation. Under a far-field set-up, the formulation can be simplified and a calibration curve for contrast and roughness can be calculated. We demonstrated the technique using a blue diode laser with a set of 20 metal surface roughness standards in the range 1–73μm, and found that the method worked well with both Gaussian and non-Gaussian surfaces. [Copyright &y& Elsevier]

• Developed a novel polarization speckle system that incorporates deep learning. • Polarization speckle data lends itself to augmentation for machine learning and deep learning. • In a clinical validation study, multiple types of skin cancers are separated from benign skin lesions. • Deep learning enables improved detection performance over machine learning and previous speckle analysis methods. Polarization speckle is a growing research field, especially for the purposes of biomedical imaging and diagnostics. The statistical uniformity of speckle creates novel opportunities for AI methods to analyze speckle patterns, as they are difficult for a human to interpret. We employed deep learning and traditional machine learning methods (Support Vector Machine, K Nearest Neighbor, and Random Forests) to analyze polarization speckle images generated from the general categories of malignant and benign lesions, a classification task previously found to be very difficult. Their performance in classifying the patterns were compared both to each other and to the previous statistical methods of speckle analysis. A collection of 122 malignant and 196 benign skin lesion speckle images were augmented for deep learning using patch cropping, an advantageous method given the patterns' statistical homogeneity. The machine learning technique performed with a diagnostic accuracy of less than 65%, a result comparable to those of previous statistical methods, despite the fact that the same machine learning technique could achieve a high 90% accuracy in the simpler classification task of differentiating malignant melanoma and the benign lookalike seborrheic keratosis. However, ResNet, our chosen deep learning architecture, achieved the best performance of 82% diagnostic accuracy in the general classification task of malignant and benign. These results show that deep learning extracts previously hidden information from polarization speckle, which further develops towards a rapid, real-time, analysis technique for an automatic skin cancer detection system. [ABSTRACT FROM AUTHOR]

Although many therapeutic modalities have been tested on alopecia areata, patient outcomes have been disappointing. Use of animal models would help to develop more efficient therapies as well as understanding therapeutic mechanisms. We have demonstrated that 0.1% topical anthralin ointment is 100% effective in restoring follicular activity in Dundee experimental balding rats. This is the most promising topical treatment for Dundee experimental balding rats among the therapeutic agents tested on this model. Various cytokines have been shown to be associated with the pathogenesis of alopecia areata. To test whether any of these cytokines might be modulated by anthralin, an RNase protection assay and the real-time polymerase chain reaction were performed to compare their expression between anthralin-treated and control skins. These experiments showed that expression of tumor necrosis factor-α and interferon-γ was inhibited by anthralin, whereas expression of interleukin-1α/β and their receptor antagonist, interleukin-1Ra, and interleukin-10 was stimulated by anthralin. In addition, using an antibody-based multi-immunoblotting technique, we found that certain signaling regulatory proteins were modulated by anthralin. Their potential roles in reversing the autoimmune-arrested follicular activity in Dundee experimental balding rats are discussed. [ABSTRACT FROM AUTHOR]

Alopecia areata is an autoimmune disease targeted at hair follicles with infiltrated T lymphocytes probably playing an important role in the pathogenesis. It was reported in 1985 that mechlorethamine was effective on alopecia areata patients. This has never been confirmed since. The aims of the study were to investigate the effects of mechlorethamine on balding C3H/HeJ mice affected with an alopecia-areata-like disease and to study the underlying mechanisms. Mice were treated on half of the dorsal skin with mechlorethamine and the contralateral side was treated with the vehicle ointment. After 10 wk of mechlorethamine therapy, a full pelage of hair covered the treated side in all the mice and was maintained during the study, whereas the vehicle-treated sides showed either no change or continued hair loss. Immunohistochemistry revealed that infiltrated CD4+ and CD8+ lymphocytes were eliminated from the treated side. In vitro cell viability assay showed that lymphocytes were much more sensitive to the cytotoxic effects of mechlorethamine than skin and hair follicular cells. RNase protection assay and real-time reverse transcription polymerase chain reaction showed that tumor necrosis factor α/β, interleukin-12, and interferon-γ were inhibited by mechlorethamine upon successful treatment. Our findings support that mechlorethamine restores follicular activity by selectively targeting infiltrated lymphocytes in vivo in alopecia-areata-affected mice. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is a recently approved treatment modality that involves the sequential administration of a photosensitizer or its precursor and light to generate singlet oxygen for treating diseased tissue. The use of topical aminolevulinic acid (ALA) and blue light for nonhypertrophic actinic keratoses currently represents the only approved dermatologic application for PDT in the U.S.A. ALA is a photosensitizer precursor that is metabolized by cells into protoporphyrin IX (PpIX), which can be subsequently activated by visible light. PDT with topical ALA has been shown to improve psoriasis, but post-treatment hyperpigmentation as well as inconsistent clinical responses despite repeated PDT sessions have limited the development of this treatment approach for psoriasis. Furthermore the use of topical PDT photosensitizers becomes somewhat impractical for treating larger body surface areas in patients with extensive psoriasis. We have recently shown that oral administration of ALA induces preferential accumulation of PpIX in psoriatic plaques. The objectives of this study were to evaluate the effects of PDT with blue light on psoriatic plaques after systemic ALA administration as well as to determine whether systemic ALA-PDT induces apoptosis in lesional T lymphocytes. It has been suggested that induction of apoptosis in lesional T lymphocytes may be indicative of longer remission time following treatment of psoriasis. [ABSTRACT FROM AUTHOR]

In evaluating the autofluorescence properties of normal and diseased skin we discovered that psoriatic plaques can emit a distinct red fluorescence when illuminated with UVA or blue light. Using a macrospectrofluorometer equipped with a 442 nm excitation laser, a sharp in vivo fluorescence emission peak around 635 nm could be demonstrated within the plaques of 34 of 75 (45%) patients with psoriasis. This peak was absent from normal appearing skin of psoriatic patients and also from the skin of 66 patients with other dermatologic diseases. A microspectrofluorometer coupled with the same excitation laser was used to obtain emission spectra of separated epidermal sheets and dermis from plaques demonstrating macroscopic red autofluorescence. An emission peak around 635 nm was observed in all three patients thus studied, but only on spectra obtained from the epidermis. Additional spectra of vertical microscopic sections of intact psoriatic skin from five other patients revealed that the peak originated from the stratum corneum. Emission spectra from other microlocations including the mid‐epidermis and dermis of psoriatic and normal skin, as well as the stratum corneum of normal skin, failed to demonstrate a 635 nm peak. The excitation and emission fluorescence spectra of acid extracts of psoriatic scale from five patients were all similar to those of protoporphyrin IX in acid solution. High performance liquid chromatography identified the presence of protoporphyrin IX in the acid extracts from psoriatic scale of the same patients. We conclude that native psoriatic plaques can exhibit red autofluorescence that is due to elevated levels of protoporphyrin IX within scales. [ABSTRACT FROM AUTHOR]

This article presents information on a study which was conducted to determine whether combined treatment with eflornithine and a pulsed infrared laser would induce greater hair reduction than laser treatment alone. The study involved female patients undergoing up to six monthly laser hair removal sessions to the entire upper lip with a 755 nm, long-pulse alexandrite laser. During the study, each patient was assigned to apply topical eflornithine 13.9% cream to one side of the upper lip and a placebo vehicle cream to the contralateral side twice daily. It was concluded that more rapid hair reduction was seen in the patients who undergone the said treatment with combined laser-eflornithine.