Polarization and depolarization metrics as optical markers in support to histopathology of ex vivo colon tissue

Tissue polarimetry holds great promise to improve the effectiveness of conventional cancer diagnostics and staging, being a fast, minimally invasive, and low-cost optical technique. We introduce an enhanced diagnostic method for ex vivo colon specimens assessment by utilizing Stokes and Mueller matrix polarimetry. The proposed method makes use of experimental Mueller matrices, measured from healthy and tumor zones of a colon specimen, as input data for post-processing algorithms that include physical realisability filtering, symmetric decomposition and estimation of various polarization and depolarization metrics for colon specimen diagnostics. We validated our results with the gold standard histological diagnostics provided by pathologists. It was found that the Stokes-Mueller matrix polarimetry, combined with the appropriate filtering, decomposition algorithms and polarization/depolarization metrics calculations provides relevant optical markers of the colon tissue pathological conditions (healthy versus cancer), as confirmed by histopathology analysis. This approach potentially provides physicians with valuable and complementary information that holds promises in helping with the diagnostics of colon tissue specimens.     

Topical retinoids in the management of photodamaged skin: from theory to evidence‐based practical approach

Skin, being exposed directly to the environment, represents a unique model for demonstrating the synergistic effects of intrinsic and extrinsic factors on the ageing process. Ultraviolet radiation (UVR) is the major factor among exogenous stressors responsible for premature skin ageing. The problem of skin ageing has captured public attention and has an important social impact. Different therapeutic approaches have been developed to treat cutaneous ageing and to diminish or prevent the negative effects of UVR. Topical retinoids represent an important and powerful class of molecules in the dermatologist’s hands for the treatment of photodamaged skin. Since their introduction more than 20 years ago, topical retinoids have shown beneficial efficacy and good safety profiles in the management of photodamaged skin, and as therapeutic anti‐ageing agents. This review provides a brief retrospective of the development of topical retinoids in the treatment of photodamaged skin, elucidates their mechanism of action, delineates their use and addresses clinical, pharmaceutical and regulatory issues in connection with their intended use.     

Acute irritant threshold correlates with barrier function,skin hydration and contact hypersensitivity in atopic dermatitis and rosacea

The aim of the study was to disclose interactions between epidermal barrier, skin irritation and sensitization in healthy and diseased skin. Transepidermal water loss (TEWL) and stratum corneum hydration (SCH) were assessed in adult patients with atopic dermatitis (AD), rosacea and healthy controls. A 4‐h patch test with seven concentrations of sodium lauryl sulphate was performed to determine the irritant threshold (IT). Contact sensitization pattern was revealed by patch testing with European baseline series. Subjects with a lower IT had higher TEWL values and lower SCH. Subjects with positive allergic reactions had significantly lower IT. In AD, epidermal barrier deterioration was detected on both volar forearm and nasolabial fold, while in rosacea, impeded skin physiology parameters were observed on the facial skin only, suggesting that barrier impediment is restricted to the face in rosacea, in contrast with AD where the abnormal skin physiology is generalized.     

Influence of skin type, race, sex, and anatomic location on epidermal barrier function

The intact skin represents a barrier to the uncontrolled loss of water, proteins, and plasma components from the organism. Owing to its complex structure, the epidermal barrier with its major layer, the stratum corneum, is the rate-limiting unit for the penetration of exogenous substances through the skin. The epidermal barrier is not a static structure. The status of different functions of the epidermis can be monitored by assessing specific biophysical parameters such as transepidermal water loss, stratum corneum hydration, and skin surface pH. Variables originating from the individual as well as exogenous factors have an important influence on the epidermal barrier parameters.     

Penicillin and vitamin A as possible therapeutic agents in pityriasis rubra pilaris

Pityriasis rubra pilaris (PRP) is a rare skin disorder with versatile clinical presentations. A 62‐year‐old Caucasian woman with progressive erythroderma and classic adult (type I) PRP is presented. Treatment with systemic steroids and methotrexate produced no improvement. Clinical remission was achieved after systemic therapy with penicillin (both intravenous and intramuscular) and vitamin A. The therapy of PRP is reviewed, focusing on a possible infectious genesis of PRP as well as the role of antibiotics in its management.     

Pemphigus vulgaris and pregnancy

The management and counseling of patients with pemphigus vulgaris during pregnancy is a challenge. The frequency of the association is very low and the current knowledge is based only on case reports or small series. The authors report 2 cases ofpemphigus vulgaris and pregnancy that differed from each other in the time of occurrence and clinical course but had similar favorable outcomes. Based on a literature review and their personal observations, the authors discuss the characteristics of this association, the therapeutic behavior, patients' followup, and fetal prognosis.     

Non-invasive in vivo methods for investigation of the skin barrier physical properties

Skin as an organ of protection covers the body and accomplishes multiple defensive functions. The intact skin represents a barrier to the uncontrolled loss of water, proteins, and plasma components from the organism. Due to its complex structure, the epidermal barrier with its major component, stratum corneum, is the rate-limiting unit for the penetration of exogenous substances through the skin. The epidermal barrier is not a static structure. The permeability barrier status can be modified by different external and internal factors such as climate, physical stressors, and a number of skin and systemic diseases.Today, different non-invasive approaches are used to monitor the skin barrier physical properties in vivo. The quantification of parameters such as transepidermal water loss, stratum corneum hydration, and skin surface acidity is essential for the integral evaluation of the epidermal barrier status. Novel methods such as in vivo confocal Raman microspectroscopy offer the possibility for precise and detailed characterization of the skin barrier.This paper will allow the readership to get acquainted with the non-invasive, in vivo methods for the investigation of the skin barrier.     

Functional skin adaptation in infancy – almost complete but not fully competent

Please cite this paper as: Functional skin adaptation in infancy – almost complete but not fully competent. Experimental Dermatology 2010; 19: 483–492. Abstract: Early postnatal life is a period of active functional reorganization and cutaneous physiological adaptation to the extrauterine environment. Skin as the outermost organ of mammalians is endowed of multiple functions such as protection, secretion, absorption and thermoregulation. Birth stimulates the epidermal barrier maturation and the skin surface acidification especially in premature infants. In full‐term infants the developed stratum corneum accomplishes competent barrier function, in contrast to prematures. Complete barrier maturation in preterm infants is fulfilled by 2–4 weeks of the postnatal life. However, in preterms with 23–25 weeks gestational age this process takes longer. Versatile regulatory mechanisms, namely skin surface acidity, calcium ion gradient and nuclear hormone receptors/ligands are interrelated in the complex postnatal newborn adaptation. The skin of newborns is adjusting quickly to the challenging environmental conditions of the postpartum. However, certain functions, for example, microcirculation, continue to develop even beyond the neonatal period, that is, up to the age of 14–17 weeks. Different environmental factors (for instance, dry and cold climate, diapers and cosmetic care procedures) influence the postnatal development of skin functional parameters such as stratum corneum hydration and the permeability barrier especially in premature infants. The aim of this article is to summarize the current knowledge on skin physiology in newborn and infants with a practical approach and to discuss the possible clinical consequences. This review offers the readership a critical and practical overview of skin physiology in newborns and infants. It emphasizes possible new research fields in neonatal and infantile skin physiology.     

Contact Dermatitis in a Child from Methlychloroisothiazolinone and Methylisothiazolinone in Moist Wipes

Abstract: Contact allergic reactions to methlychloroisothiazolinone/methylisothiazolinone also widely known as Kathon CG have been reported extensively reported. It is one of the most commonly used preservatives in rinse‐off products, cosmetics, and others. Herein, a case of a 50‐year‐old girl is presented with chronic dermatitis in the anogenital area. The patient was patch tested and had positive reaction to Kathon CG. The detailed history taking revealed that the allergen was present in the moist cleaning wipes used instead of dry toilet paper. The presented case serves as a basis for a appraisal of the use of this preservative in wet wipes. In addition, the duration of the patch test protocol in children has also been discussed.