Melanoma is notoriously resistant to immuno- and even targeted chemotherapeutic strategies despite recent advances in drug development. The overall mortality of melanoma correlates with its ability to metastasise. Breslow thickness or the depth of invasion remains the most useful prognostic indicator, thereby linking the ability of the cells to invade with their propensity to metastasise. Invasion occurs early during tumour development, but the factors driving this process remain poorly understood. There is a growing appreciation that chemotaxis plays an important role in driving the migration and invasion of melanoma cells, but the key stimuli are not known. Through the generation and validation of an improved chamber for cancer cell chemotaxis, melanoma cells are shown to create chemotactic gradients that drive or disperse themselves outwards with remarkable efficiency. This process is driven by strikingly positive chemotaxis and depends on the melanoma reaching a critical density to generate the gradient. The principal attractant is the inflammatory signal lysophosphatidic acid (LPA). Unexpectedly, it is active across all stages of melanoma evolution and LPA is both necessary and sufficient for chemotaxis in 2D & 3D assays. Growth Factors were previously considered to play essential roles in driving directed migration, but instead facilitate LPA chemotaxis. Sampling across the margins of melanomas in vivo, gradients of LPA are reliably identified, which are capable of driving accurate chemotaxis. This not only confirms the physiological importance of the results, but also is the first time a chemoattractant gradient has been measured in vivo. The corollary of these findings is that, provided with an external homogenous source of LPA, a large enough melanoma will degrade the local LPA to generate an outward gradient. Therefore it is the ability to degrade the gradient that acts as the signal to drive chemotaxis and invasion rather than the presence of LPA per se. In the chambers, cells are observed dispersing in a wave and in addition to driving efficient melanoma invasion, this may be responsible for the patterning of melanocytes across the skin during embryogenesis. Ultimately, identifying key aspects of and targeting the LPA-axis may prove a novel prognostic indicator and therapeutic target for invasion and metastasis.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Human cancer stem cells are proposed to play a critical role in tumour initiation and maintenance by their exclusive ability to regenerate the tumour. Thus cancer stem cells share many of the properties of normal stem cell including self-renewal and ability to give rise to progeny which undergo tissue-specific differentiation. Thus we hypothesised that by determining the normal patterns of tissue differentiation within cancer we could identify tumour type specific factors that promote differentiation, for therapeutic development. Therefore the aim of this study is to define patterns of human hair follicle differentiation in human basal cell carcinoma (BCC) in order to elucidate potential drug-able targets that can promote tumour specific differentiation. To test this hypothesis we analysed 20 different hair follicle specific differentiation markers, which define distinct layers within the normal adult hair, in six different human BCC samples using RT-PCR with normal hair follicle tissue as control. For the 12 specific keratin genes expressed in the BCC, we analysed expression by immunofluorescence on 20 different BCC samples, using hair follicle samples as positive controls. Our findings suggest that human BCC demonstrates both inward and upward differentiation patterns similar to the hair follicle, with expression of: outer root sheath (K5,14,16,and k17), companion layer (K75), inner root sheath (K26,27,28,71,72,and k74), and cuticle (K32,35,82,and k85); but not hair shaft (K31) markers. Consistent with these findings we observed the mutually exclusive relationship between expression of the early differentiation marker K19 and cell proliferation in the hair follicle and BCC. Similarly, expression of the outer root sheath keratins coincided with nuclear translocation of both GLI1 and NFIL-6, suggesting that BCC also share normal hair follicle tissue regulatory pathways. To further test the hypothesis that normal tissue factors observed in the hair follicle regulate BCC differentiation we have developed an in vitro BCC assay. Using this tissue culture model we hypothesised that BCC’s are stuck in the telogen part of the hair follicle cycle, resulting from autocrine expression of bone morphogenic proteins 2 and 4. Inhibition of BMP signalling by addition of noggin as well as addition of TGF-β to BCC colonies in tissue culture led to further induction of inner root sheath, cuticle and medulla keratins. In summary we have shown that BCC exhibit hair follicle differentiation, which is similarly regulated, but is stuck in telogen arrest and can be rescued by addition of noggin and TGF- β2.

Epigenetic regulation is now known to play an important role in determining stem cell fate during normal tissue development and disease pathogenesis. In this study, we report loss of 5-hydroxymethylcytosine (5-hmC) mediated by ten-eleven translocation (TET) methylcytosine dioxygenases in keratinocyte stem cells (KSCs) and in their progenitor transit-amplifying (TA) cells of psoriatic lesions. We establish the DNA hydroxymethylation profile in both human psoriasis as well as in the imiquimod (IMQ)-induced mouse psoriasis model. Genome-wide mapping of 5-hmC in IMQ-treated mice epithelium revealed a loci-specific reduction of 5-hmC in genes associated with maintaining stem cell homeostasis including those involved in the RAR and Wnt/β-catenin signaling pathways. Restoration of TET expression in human KSC cultures via vitamin C treatment increased 5-hmC levels and induced more normal KSC differentiation. We found that by modulating 5-hmC levels in vitro, we could alter downstream expression of genes important in regulating stem cell homeostasis like nestin as well as IL-17R known to promote the psoriatic phenotype. Our findings demonstrate that loss of 5-hmC is a critical epigenomic phenomenon in KSCs and TA cells during psoriasis pathogenesis. / 2019-12-17T00:00:00Z

Overexposure to UV (ultraviolet) radiation has been linked to a number of deleterious effects on human health, particularly epidermal malignancies, which consist of both melanoma and non-melanoma skin cancers, basal cell carcinoma and squamous cell carcinoma. In the 1950’s, an epidermal compound known as Urocanic Acid (UCA) was discovered whose trans isoform was shown to display photoprotective effects against UV radiation. Not long after, the cis-UCA isomer was found to act as a mediator of immune suppression, causing UCA to be removed from all cosmetic products on the commercial market, most notably sunscreen. Numerous studies conducted after this finding further corroborated cis-UCA’s immunosuppressive properties, showing evidence for the ability of cis-UCA to inhibit contact hypersensitivity responses, delayed-type hypersensitivity responses, and allograft rejection. Early evidence for a mechanism of action behind cis-UCA’s immunosuppressive properties were widespread, including modulation of antigen-presenting cells, interaction with histamine receptors, and regulation of cytokine expression. The immunosuppressive nature of cis-UCA quickly became associated with an ability to facilitate cancerous progression, particularly regarding epidermal malignancies. Interesting theories were raised about the evolutionary basis for cis-UCA’s immunosuppressive nature, including speculation that cis-UCA was meant to induce immunosuppression following ultraviolet exposure in order to prevent autoimmune responses against sunburned epidermal cells. After the turn of the 20th century, new research continued to facilitate modern day understanding of the role of UCA. Evidence showed that UCA was ultimately derived from filaggrin within the stratum corneum, interacted with key immune effectors including T-lymphocytes and Langerhans cells, and potentially contributed to acidification of the stratum corneum. Despite the negative reputation cis-UCA has received in regards to facilitating skin cancer evasion of the immune system, research has shown that its immunosuppressive effects may allow it to serve as potent anti-inflammatory therapeutic. In regards to skin cancer, targeting of UCA as a therapeutic varies widely. Some have suggested using UCA as a measure of sunscreen efficacy, as an indirect target that when inhibited can reduce tumor growth, and as a biomarker for skin cancer risk. Others have begun developing UCA-based mimics that retain the benefits of UCA, while avoiding any deleterious effects. The role of UCA in non-melanoma and melanoma malignancies is not well understood, making targeting of UCA as a therapeutic challenging. The aim of this paper is to comprehensively review the scientific literature regarding the pre-21st century history of UCA, followed by an in-depth analysis of post-21st century research. The objective is to determine the overall potential of UCA to serve as a therapeutic target for UV-associated health conditions, most notably dermatologic malignancies.

Introdução: A hanseníase pode acometer a pele e o sistema nervoso periférico podendo levar a graves deformidades. É causada pelo Mycobacterium leprae, bacilo álcool-ácido resistente, parasita exclusivamente intracelular. Atualmente, a hanseníase é classificada em dois grandes grupos: paucibacilar (menos de cinco lesões) e multibacilar (mais de cinco lesões). É um problema de saúde pública, estando o Brasil entre os países de maior endemicidade no mundo. A morbidade dessa doença milenar se deve ao fato de causar incapacidades, por vezes irreversíveis, além do estigma que a acompanha, levando ao comprometimento da qualidade de vida. Vários trabalhos têm sido realizados a respeito da qualidade de vida em doenças dermatológicas, como psoríase, dermatite atópica, acne, herpes genital, hanseníase, no sentido de se tentar avaliar o grau de comprometimento do bem-estar físico, psicossocial e de atividades da rotina diária, assim como se tentar melhorar a relação médico-paciente e das ações de saúde, com o intuito de se minimizar os problemas decorrentes de cada enfermidade. Objetivo: avaliar o comprometimento da qualidade de vida nos pacientes do grupo paucibacilar de hanseníase em tratamento ambulatorial. Métodos: aplicação dos questionários Dermatology Life Quality Index e Short Form-36. O Dermatology Life Quality Index é um questionário específico para a dermatologia e é constituído de 10 questões, cujo escore varia de zero a 30, sendo o máximo valor (30) relacionado ao maior comprometimento da qualidade de vida. O Short Form-36, questionário mais genérico, abrange oito domínios (Capacidade Funcional, Aspectos físicos, Dor, Estado geral de saúde, Vitalidade, Aspectos sociais, Aspectos emocionais e Saúde mental), distribuídos em 11 questões, cada qual com número variável de itens, perfazendo 36 itens, que nos dá um escore que pode variar de zero a 100, sendo o maior escore (100) atribuído ao menor comprometimento da qualidade de vida. Foram aplicados esses dois questionários em 49 doentes com hanseníase do grupo paucibacilar. Resultados: Dos 49 pacientes que participaram do estudo, 36 do sexo feminino e 13 do sexo masculino, a maioria (63%) não apresentou comprometimento da qualidade de vida, de acordo com os resultados obtidos através do questionário Dermatology Life Quality Index. Ao aplicar o questionário genérico Short Form - 36, os escores alcançados nos diversos domínios também demonstraram pouco comprometimento da qualidade de vida no grupo estudado / Introduction - Leprosy can affect the skin and peripheral nervous system and can lead to severe deformities. It is caused by Mycobacterium leprae, Bacillus acid-resistant, an intracellular parasite exclusively. Currently, leprosy is classified into two major groups: paucibacillary (less than five lesions) and multibacillary (more than five lesions). It is a public health problem, with Brazil among the countries with the highest endemicity in the world. The millennial morbidity of this disease is due to the fact that causes disabilities, sometimes irreversible, besides the stigma that accompanies it, compromising the quality of life. Several studies have been conducted regarding the quality of life in dermatological diseases such as psoriasis, atopic dermatitis, acne, genital herpes, leprosy, in order to try to assess the degree of impairment of physical well-being, psychosocial and daily routine activities as well as try to improve the doctor-patient relationship and health actions in order to minimize problems arising from each disease. Objective: To assess the actual quality of life for patients in group paucibacillary leprosy outpatients. Methods: application of the Dermatology Life Quality Index questionnaire and Short Form-36. The Dermatology Life Quality Index is a dermatology-specific questionnaire and consists of 10 questions which score ranges from zero to 30, with the maximum value (30) related to greater impairment of quality of life. The Short Form-36, more generic questionnaire covers eight domains (Physical Functioning, Role Physical, Pain, General Health, Vitality, Social, Emotional and Mental Health Aspects), distributed in 11 questions, each with varying number of items, totaling 36 items, which gives a score that can range from zero to 100, with the highest score (100) assigned to lower impairment of quality of life. These two questionnaires were applied in 49 patients with paucibacillary leprosy group. Results: Of 49 patients who participated in the study, 36 females and 13 males, most (63%) did not show quality of life compromising, according to the results obtained by the Dermatology Life Quality Index questionnaire. By applying the generic questionnaire SF - 36, the scores achieved in several domains also showed little decrease in quality of life in the studied group

INTRODUÇÃO: Onicomicose é a infecção fúngica das unhas e é considerada a onicopatia mais frequente em adultos. Representa até 50% das lesões ungueais, sendo necessária confirmação diagnóstica com exame complementar que demostre a presença do fungo na unha, sendo o exame micológico direto e a cultura para fungos os mais utilizados. A dermatoscopia é um exame não invasivo, rápido e de baixo custo cujos padrões para onicomicose relatados na literatura em estudos retrospectivos chegam a 100% de sensibilidade e especificidade. Deste modo realizamos um estudo prospectivo para comparar a dermatoscopia frente ao exame micológico. MÉTODOS: Estudo prospectivo, transversal avaliando 109 pacientes e 202 unhas com suspeita diagnóstica de onicomicose. Os padrões dermatoscópicos encontrados foram descritos através de fotografias digitais. A sensibilidade e especificidade dos padrões de onicomicose distal-lateral foram determinados de acordo com o resultado do exame micológico. RESULTADOS: Foram significativos (p < 0,05) para o diagnóstico de onicomicose distal lateral e tiveram sensibilidade/especificidade calculadas os padrões: borda recortada (80,2% / 65,3%), borda linear (12,6% / 42,9%), estrias irregulares (81,1% / 65,3%), estrias finas/regulares (9,9% / 59,2%); e as cores branco (93,7% / 18,4%), amarelo (63,1% / 71,4%) e laranja (10,8% / 100%). Após análise multivariada stepwise forward os padrões de estrias irregulares, borda linear e cor amarela mantiveram significância estatística (p < 0,05). DISCUSSÃO: Os achados deste trabalho prospectivo estão de acordo com a literatura mostrando que há correlação entre o exame micológico e a dermatoscopia. Todavia, não ratifica a sensibilidade e especificidade de 100% encontrada em estudo retrospectivo para os padrões de borda recortada e borda linear. Também não demonstrado na literatura, as cores amarela, branca e laranja foram também estatisticamente significativas para o diagnóstico. CONCLUSÃO: A dermatoscopia correlaciona bem com a história natural da infecção fúngica e com o exame micológico, sendo um exame promissor para o diagnóstico de onicomicose. Sugerimos que futuros estudos comparem a dermatoscopia com exames considerados padrão-ouro (ex: microscopia de fluorescência e PCR) para detectar exames falso negativos / BACKGROUND: Onychomycosis is defined as a fungal infection of the nail and is considered the most common onychopathy in adults. It represents up to 50% of nail diseases and demonstration of the fungal pathogen is necessary for diagnostic confirmation. Direct mycological examination and fungal culture are commonly used for this purpose. Dermoscopy is a noninvasive, fast and inexpensive exam, reaching 100% diagnostic sensitivity and specificity for onychomycosis in retrospective studies. Thus, we conducted a prospective study to compare dermoscopy with mycological examination. METHODS Prospective, cross-sectional study with 109 patients and 202 nails evaluated. Dermoscopic patterns were described using digital photography and their sensitivity and specificity for distal-lateral onychomycosis were determined. RESULTS: Statistically significant (p < 0.05) patterns and colors for the diagnosis of distal-lateral onychomycosis and respective sensitivity / specificity: jagged edge (80.2% / 65.3%), linear edge (12.6% / 42 , 9%), longitudinal irregular streaks (81.1% / 65.3%), longitudinal fine / regular streaks (9.9% / 59.2%); white color (93.7% / 18.4%), yellow color (63.1% / 71.4%) and orange color (10.8% / 100%). After a stepwise forward multivariate analysis irregular streaks, linear edge and yellow color remained statistically significant (p < 0.05). DISCUSSION: Findings of this prospective study are in agreement with the literature showing that there is correlation between mycological examination and dermoscopy. However, this study does not agree with 100% sensitivity and specificity found in retrospective studies for jagged edge and linear edge patterns. In addition, white, yellow and orange colors were also statistically significant for the diagnosis of onychomycosis. CONCLUSION: Dermoscopy correlates well with the natural history of fungal nail infection and mycological examination, and we consider it a promising method for the diagnosis of onychomycosis. We suggest that future studies compare dermoscopy with a gold standard exam (ex: fluorescence microscopy, PCR) to detect false negative cases

A distribuição da energia espacial do feixe de laser é de grande importância para a eficiência em tratamentos dermatológicos. Os métodos existentes para a calibração do feixe podem ser realizados por meio de equipamentos óticos ou por materiais fotossensíveis. Este trabalho apresenta uma metodologia que pode ser descrita por quatro fases. Na primeira, foi obtido o polímero poliacetal, material que foi responsável por registrar o perfil transversal do feixe de laser (Nd:YAG 1064 nm). Na segunda fase os valores referenciais dos parâmetros do feixe foram extraídos por meio do método knife edge. Posteriormente, as técnicas de processamento de imagem foram aplicadas sendo responsáveis pela extração de características do feixe registradas no polímero. Como resultados, determinaram-se os seguintes parâmetros: área do feixe, circularidade, perfil da borda, assinatura, diâmetros, divergência e cintura do feixe. Na última fase o feixe foi classificado em calibrado e descalibrado por meio da Rede Neural Artificial (RNA) Multilayer Perceptron (MLP), que apresentou 88,5% de taxa de acertos. Outro parâmetro utilizado para a calibração foi a circularidade, onde adotou-se o valor limiar de 0,85 para decisão entre feixes calibrados e feixes descalibrados. Frente aos resultados obtidos, considera-se bem sucedida a proposta para a inspeção de qualidade de feixe laser para aplicação dermatológica, apresentando-se como um método de calibração alternativo com maior precisão quando comparado a análises por meio da visualização humana. / The spatial distribution of laser beam energy is of great importance to the efficiency of dermatologic treatments. The existing methods beam calibration can be performed with optical equipment or photosensitive materials. This paper presents a methodology which can be described by four phases. At first it was obtained polyacetal polymer, a material that was responsible for registering the transverse profile of the laser beam (Nd:YAG 1064 nm). In the second phase, the reference values of the beam parameters were extracted using the knife edge method. Subsequently, the image processing techniques were applied being responsible for extracting features of the beam recorded in the polymer. As a result, we determined the following parameters: beam area, circularity, the edge profile, signature, diameter, divergence and beam waist. In the last phase the beam was classified calibrated and uncalibrated with Artificial Neural Network (ANN) Multilayer Perceptron (MLP), which showed 88.5% hit ratio. Another parameter used for calibration was the circularity, where we adopted the threshold value of 0.85 for decision between calibrated and uncalibrated beams. Given our results, it is considered a successful proposal for the quality inspection of laser beam for dermatological application, presenting itself as an alternative method of calibration with greater precision when compared to analyzes by human viewing.

Para analisar a efetividade da teledermatologia assistencial a partir de fotografias digitais de lesões, avaliou-se a sistematização de aspectos técnicos, morfológicos (maculoso, relevo e palpatório) e de representatividade clínica (típico, moderado e atípico). Verificou-se que o comprometimento da qualidade técnica, a morfologia palpatória e menor tipicidade clínica devem ser suplementados pela descrição das lesões e pelas informações clínicas para aumentar sua acurácia diagnóstica. Desenvolveu-se um sistema de interconsulta dermatológica à distância e constatou-se que seu desempenho diagnóstico foi comparável à consulta presencial, devendo ser consideradas todas as hipóteses diagnósticas elaboradas, além da principal / To analyze the effectiveness of a teledermatology system, the systematization of digital photographs from cutaneous lesions on technical quality, morphologic and clinical aspects was performed. The study showed that unsatisfactory technical quality, palpatory morphology and less typical lesions should be supplemented by clinical description of the lesions and patient information to increase diagnostic accuracy. The dermatologic Internet-based teleconsultation system has diagnostic performance comparable to face-to-face consultation, and all the hypotheses, not only first one, should be considered at virtual diagnostic evaluation

Itch lies second only to disturbance of body image as a reported symptom in dermatology. This study started by concentrating on improving the measurement of itch. Itch has a paired physical response, scratch. The pairing can be exploited: preliminary work by this unit had validated the use of wrist-worn movement-measuring machines called ‘accelerometers’ to measure itch-related movement (scratch and rub). The first part of this research developed use of these machines. Simple accelerometers (‘Actiwatch Plus’) were used to observe the pattern of variation of itch over clusters of nights and in different conditions. The accelerometer scores were able to identify controls’ scores from those with itchy disease. Considerable variation (56%) was discovered in objective score between subject and considerable variation was noted (46%) even within subject. More complex accelerometers, (‘DigiTrac’) which could potentially specifically identify itch-related movement on the basis of frequency of action derived from Fast Fourier Transform (FFT), were validated against the ‘gold standard’ measurement of itch-related movement, directly observed movement (via infra red video recording). It was necessary to characterise the ‘frequency of action’ of itch on video and, as an aside, the characteristics of human itch-related movement were compared to other mammals’ itch-related movement ‘frequency of action’. The ‘frequency of action’ and video data was used to enrich the DigiTrac readouts to improve specificity of itch-related movement detection. During the accelerometer studies, an unexpected finding came to light: objective score of itch was not related to subjective score. To try to explain the lack of relationship, a 42 day longitudinal study of atopic dermatitis patients’ subjective and objective scores was undertaken. The results demonstrated autocorrelation for subjective scores, but not for the objective scores but still did not fully explain the lack of relationship. In an effort to explain the disconnect between subjective and objective scores a second tranche of experiments and the second part of this research interrogated whether the methods with which we measure disease as a whole in dermatology are robust. One study investigated whether the way patients are asked about subjective symptoms in general was resistant to the effects of focusing and framing bias. The results were reassuring as they suggested that the commonly used and recommended symptom scoring systems were robust in the face of bias. In order to assess whether perspective or perception of disease explained the disconnect, a study was designed in collaboration with the Edinburgh College of Art. A series of computer-generated images of different psoriasis severities were created and used to assess how doctors and patients assessed disease-extent. This study showed that, whilst each group had a naturally divergent opinion of extent of disease, by scoring disease using the models it was possible to unify the perspective and perception of extent. Finally, an exploratory study to reduce recall bias to a minimum, in case this had caused the disconnect between objective and subjective, was undertaken. This employed a novel questionnaire, the Day Reconstruction Method.