Characteristics of the ageing skin, xerosis cutis and its complications

People in the developed countries are living longer. Geriatric dermatology is playing an increasingly important role as chances of developing skin-related problems increase with their ageing. Skin ageing is induced by two main processes: intrinsic and extrinsic. Extrinsic ageing is caused by environmental factors such as sun exposure, smoking, alcohol consumption, air pollution, and poor nutrition. Intrinsic ageing reflects the genetic background and depends on time. The aged skin is characterised by the appearance of dryness, atrophy, wrinkles, pigmented lesions, patchy hypopigmentation, and elastosis. This article provides an overview of skin ageing processes and common conditions found in the elderly persons such as xerosis, pruritus, and eczema.

Defining the Validity of Skin Self-Examination as a Screening Test for the Detection of Suspicious Pigmented Lesions: A Meta-Analysis of Diagnostic Test Accuracy

<b><i>Background:</i></b> Skin self-examination (SSE) is widely promoted for the detection of suspicious pigmented lesions. However, determining screening accuracy is essential to appraising the usefulness of SSE. <b><i>Objectives:</i></b> The aim of this work was to pool estimates from studies of SSE diagnostic accuracy in the detection of suspicious pigmented lesions. <b><i>Methods:</i></b> This study was registered with PROSPERO (CRD42021246356) and conducted in accordance with PRISMA-DTA guidelines. A systematic search of Medline (PubMed) EMBASE, CINAHL, and The Cochrane Library was conducted to identify relevant studies. We included studies that examined the accuracy of SSE, either whole-body or site-specific, for detecting change in individual pigmented lesions or detecting an atypical naevus. A univariate random-effects model, based on logit-transformed data, was used to calculate a summary diagnostic odds ratio (DOR) as well as pooled sensitivity and specificity. Cochran’s <i>Q</i> test and the <i>I</i>² statistic were calculated to assess heterogeneity. A proportional hazards model was used to calculate the area under the curve (AUC) and plot the summary receiver operator characteristic curve. We used the Quality Assessment of Diagnostic Accuracy Studies-2 tool to grade study quality. <b><i>Results:</i></b> We identified 757 studies, of which 3 met inclusion criteria for quantitative synthesis. The pooled sensitivity and specificity based on 553 included participants was 59 and 82%, respectively. The summary DOR was 5.88 and the AUC was 0.71. There were some concerns regarding risk of bias in all 3 studies. <b><i>Conclusions:</i></b> SSE can detect suspicious pigmented lesions with reasonable sensitivity and relatively high specificity, with the AUC suggesting acceptable discriminatory ability.

Pigmented Lesions of the Eyelid Margin

The eyelid area poses a diagnostic and therapeutic challenge due to its specific anatomy. The eyelid is composed of skin, orbicularis muscle, tarsus, and the eyelid margin is continuous with palpebral conjunctiva. Among pigmented tumors, benign lesions such as epidermal or intradermal nevi, freckles, lentigo, or seborrheic keratosis are the most common. Melanoma is relatively rare in this location. A suspicious lesion may be biopsied or excised. Surgery in the eyelid area requires special considerations to maintain a safe surgical margin, vital function of the eyelid, and acceptable cosmetic effect due to the exposure of the eyelid region of the face.

YK-4-279 Attenuates Progression of Pre-Existing Pigmented Lesions to Nodular Melanoma in a Mouse Model

More options are needed for the effective treatment of melanoma. In a previous study, we discovered the small molecule drug YK-4-279 almost completely inhibited tumor progression in the BrafCA;Tyr-CreERT2;Ptenflox/flox transgenic mouse model. YK-4-279 had no effect on tumor initiation but blocked progression of invasive melanoma. Our current study was designed as a treatment model, where YK-4-279 was administered during pigmented lesion formation. The study design included the use of three groups: (1) a control group that received only DMSO without a drug (MOCK), (2) mice following our prior studies with YK-4-279 administered at the time of tumor induction (YK-4-279), and (3) mice treated during tumor initiation (YK-4-279 delay). While the MOCK mice had progression of tumors, both YK-4-279 and YK-4-279 delay groups had a significant block or delay of progression. The majority of mice in the YK-4-279 groups had a block of progression, while the YK-4-279 delay group had either a partial block (60% in male mice or 29% in females) or a delay in disease progression in females (28 days in controls to 50 days in YK-4-279 delay group). Here, we demonstrate that YK-4-279 has a significant impact on blocking or delaying tumor progression in a pre-clinical treatment model of melanoma.

Malassezia Species Associated Seborrheic Dermatitis and Its Comparison between HIV Positive and Negative Patients

Introduction: Malassezia yeasts are lipophilic organisms causing certain skin diseases. Seborrheic dermatitis (SD) is the second most common skin infection caused by Malassezia as well as in HIV/AIDS. Aim: To determine the frequency of association of Malassezia species in HIV infected and HIV non-infected patients with Seborrheic dermatitis. Materials and Methods: The prevalence of Seborrheic dermatitis is 5% in the general population. Hence a sample size of 80 was derived, 40 each of HIV seropositive and HIV seronegative adult patients clinically suspected of having Seborrheic Dermatitis. Specimens were collected by scraping and cellophane tape for KOH and Chicago Sky Blue (CSB) stain, and were cultured on Sabouraud’s dextrose agar. Data were analysed using SPSS version 16.0. P ≤ 0.05 was considered as significant. Results: Majority of the patients i.e. 46 (57.5%) out of 80 were in the age group of 18-30 years with male preponderance. All HIV positive patients with SD had scaly, greasy, itchy, hypo-pigmented and erythematous lesions, & neck (23) and groin (20) were commonest sites. In 39 HIV positive and 22 HIV negative patients, >2 sites were involved. Majority of the HIV negative patients with SD had scaly (40), itchy (24) and hypo-pigmented lesions (27) & dandruff, and scalp (24) & neck (18) were commonest sites. (P<0.05). Twenty HIV positive patients had CD4 count ranging from 200-350 cells/mm3. Malassezia was detected in 38 and 34 HIV positive & negative patients respectively in laboratory diagnosis. Conclusion: Seborrheic Dermatitis has severe presentation at multiple sites in HIV positive patients as compared to HIV negative patients. Key words: Malassezia, Seborrheic dermatitis, HIV positive, HIV negative.

Mutations in a barley cytochrome P450 gene enhances pathogen induced programmed cell death and cutin layer instability

Disease lesion mimic mutants (DLMMs) are characterized by the spontaneous development of necrotic spots with various phenotypes designated as necrotic (nec) mutants in barley. The nec mutants were traditionally considered to have aberrant regulation of programmed cell death (PCD) pathways, which have roles in plant immunity and development. Most barley nec3 mutants express cream to orange necrotic lesions contrasting them from typical spontaneous DLMMs that develop dark pigmented lesions indicative of serotonin/phenolics deposition. Barley nec3 mutants grown under sterile conditions did not exhibit necrotic phenotypes until inoculated with adapted pathogens, suggesting that they are not typical DLMMs. The F2 progeny of a cross between nec3-γ1 and variety Quest segregated as a single recessive susceptibility gene post-inoculation with Bipolaris sorokiniana, the causal agent of the disease spot blotch. Nec3 was genetically delimited to 0.14 cM representing 16.5 megabases of physical sequence containing 149 annotated high confidence genes. RNAseq and comparative analysis of the wild type and five independent nec3 mutants identified a single candidate cytochrome P450 gene (HORVU.MOREX.r2.6HG0460850) that was validated as nec3 by independent mutations that result in predicted nonfunctional proteins. Histology studies determined that nec3 mutants had an unstable cutin layer that disrupted normal Bipolaris sorokiniana germ tube development.

The “Virtual Biopsy” of Cancerous Lesions in 3D: Non-Invasive Differentiation between Melanoma and Other Lesions Using Vibrational Optical Coherence Tomography

Early detection of skin cancer is of critical importance to provide five year survival rates that approach 99%. By 2050, one out of five Americans by age 70 will develop some form of skin cancer. This will result in a projected rate of 50 million skin biopsies per year given the current rate of escalation. In addition, the ability to differentiate between pigmented lesions and melanomas has proven a diagnostic challenge. While dermoscopy and visual analysis are useful in identifying many skin lesions, additional non-invasive techniques are needed to assist in the analysis of difficult to diagnose skin tumors. To augment dermoscopy data, we have developed 3D maps based on physical biomarker characteristics of benign and cancerous lesions using vibrational optical coherence tomography (VOCT). 3D images based on quantitative physical data involving changes in cellular and fibrous tissue stiffness along with changes in vascular quality are used to map and evaluate different types of cancers. 3D tumor maps constructed using quantitative VOCT data and OCT images have been used to characterize the differences between melanoma and other lesions. These characteristics can be used to plan the excision of difficult lesions where extensive surgery may be needed to remove the entire tumor in one step. In addition, it is now possible to use dermoscopy and VOCT to non-invasively differentiate between different cancerous lesion types using measurements of the resonant frequency of new cellular and vascular peaks. Quantitative VOCT information along with dermoscopic findings can be collected and analyzed remotely using artificial intelligence to improve cancerous tissue diagnosis.

Pigmented Oral Lesions: A Multicenter Study

Objectives The aim of this study was to determine the prevalence and clinical features of pigmented oral lesions from Thailand. Materials and Methods Biopsy records of the Department of Oral Pathology, Chulalongkorn University, Department of Oral Diagnosis, KhonKaen University, Department of Oral Biology and Oral Diagnostic Sciences, Chiangmai University, Department of Stomatology, Prince of Songkla University, and Rangsit University were reviewed for oral pigmented lesions diagnosed during 1999 to 2019. Demographic data were culled from the biopsy records. Ages of the patients were subdivided into 10-year intervals. Locations of the lesions were classified as gingiva, labial/buccal mucosa, palate, floor of the mouth, tongue, as well as the combination of sites. Data were analyzed by descriptive statistics using SPSS version 20.0. Results Of the 47,175 accessioned cases, 241 cases (0.51%) were diagnosed in the category of pigmented oral lesions. The age of the patients ranged from 1 month to 88 years with the mean ± standard deviation = 38.74 ± 20.96 years. Regarding gender, 172 patients (71.37%) with pigmented lesions were females, while 69 patients (28.63%) were males. The female-to-male ratio was 2.49:1. The majority of the pigmented lesions were encountered at the gingiva (29.88%) followed by labial/buccal mucosa (26.97%), palate (14.94%), lip (10.79%), alveolar mucosa (9.54%), and others (7.88%), respectively. The three most common pigmented oral lesions in the present study were nevus (39.83%), followed by melanotic macule (28.63%) and amalgam tattoo (17.43%), respectively. Conclusions The most common pigmented oral lesion in the present study is nevus. Demographic data of the patients in the present study are in accordance with previous studies with minor differences. Even though pigmented lesions of the oral cavity constitute a small portion of the oral pathology biopsies, accurate diagnosis is important since there is an overlap in clinical appearance of benign pigmented lesions and melanoma.

Skin Cancer Detection Based on Extreme Learning Machine and a Developed Version of Thermal Exchange Optimization

Melanoma is defined as a disease that has been incurable in advanced stages, which shows the vital importance of timely diagnosis and treatment. To diagnose this type of cancer early, various methods and equipment have been used, almost all of which required a visit to the doctor and were not available to the public. In this study, an automated and accurate process to differentiate between benign skin pigmented lesions and malignant melanoma is presented, so that it can be used by the general public, and it does not require special equipment and special conditions in imaging. In this study, after preprocessing of the input images, the region of interest is segmented based on the Otsu method. Then, a new feature extraction is implemented on the segmented image to mine the beneficial characteristics. The process is then finalized by using an optimized Deep Believe Network (DBN) for categorization into 2 classes of normal and melanoma cases. The optimization process in DBN has been performed by a developed version of the newly introduced Thermal Exchange Optimization (dTEO) algorithm to obtain higher efficacy in different terms. To show the method’s superiority, its performance is compared with 7 different techniques from the literature.