Linear patterns of the skin and their dermatoses

Knowledge about the linear patterns of the skin is a key competence of dermatologists. Four major groups of linear patterns can be distinguished: Langer lines, dermatomes, Blaschko lines and exogenous patterns. Langer lines run in the direction of the underlying collagen fibers (least skin tension) and play an important diagnostic role for some exanthematous skin diseases. In the thoracodorsal region, the distribution of the Langer lines gives rise to what is referred to as a ’Christmas tree pattern’. A dermatome is an area of skin that is supplied by a single spinal nerve. Disorders with a neuronal origin follow this pattern of distribution. The lines of Blaschko delineate the lines of migration of epidermal cells during embryogenesis. Exogenous linear patterns are caused by external factors. The present CME article will highlight important skin disorders that primarily present in the form of one of the aforementioned patterns. In addition, we will also address skin conditions that may secondarily follow with these patterns (or distinctly not do so) as the result of various mechanisms such as the Koebner phenomenon, reverse Koebner phenomenon, and Wolf’s isotopic response

Pollen grains induce a rapid and biphasic eczematous immune response in atopic eczema patients

Introduction: Eczematous reactions to type I allergy-inducing antigens are documented in a subgroup of patients with atopic eczema. Yet, the underlying immunological mechanisms are not well understood. Material and Methods: To delineate the effect of native pollen grains on human skin of healthy and atopic individuals we performed patch tests (atopy patch test with native pollen grains, PPT). Nickel patch tests (NPT) served as an established model of contact dermatitis. Skin site biopsies were taken 6 - 96 h after allergen application and investigated immunohistochemically. Results: Histology of positive patch tests showed an influx of mononuclear cells (predominantly CD4+, CD25+, CD45RO+). This influx was detected earlier in the PPT reaction than in the immune response to nickel. A biphasic cytokine response could be detected in the PPT: IL-5 dominated in the early, IFN-gamma in the late phase. The NPT was continuously dominated by IFN-gamma. Dendritic cell subpopulations imitated the earlier kinetics of the mononuclear infiltrate. Discussion: Thus, pollen grains induce eczematous reactions in susceptible individuals. This reaction appears clinically and immunohistochemically similar to the contact hypersensitivity reaction to nickel but follows a faster kinetic and a biphasic course: Th2 and IgE in the early (24 h) and Th1 predominance in the late (96 h) phase. Copyright (c) 2007 S. Karger AG, Basel

Measurement, reporting and verification of livestock GHG emissions by developing countries in the UNFCCC: current practices and opportunities for improvement

This report provides an overview of current practices, challenges and opportunities in the measurement, reporting and verification (MRV) of livestock greenhouse gas (GHG) emissions and emission reductions by developing countries in the context of the United Nations Framework Convention on Climate Change (UNFCCC). MRV of livestock GHG emissions is relevant because (i) livestock production makes a significant contribution to global GHG emissions; (ii) livestock GHG emissions have been contributing an increasing share of agricultural emissions over time; and (iii) better characterization of livestock GHG emissions can assist policy makers to target and design efforts to mitigate GHG emissions. As national climate change mitigation policies increasingly focus on GHG reduction targets in Nationally Determined Contributions (NDCs), this report assesses the extent to which current MRV practices are able to meet the evolving policy needs. The report describes MRV obligations under the UNFCCC (Chapter 2), current practices in compiling and reporting livestock GHG emissions through national GHG inventories (Chapter 3) and MRV of mitigation actions (Chapter 4), and highlights opportunities for improvement (Chapter 5).This report is also available in:French: http://hdl.handle.net/10568/93125Spanish: http://hdl.handle.net/10568/93127A summary brief is available at: http://hdl.handle.net/10568/80890

Shifting food consumption to mitigate climate change is critical to fulfilling the Paris Agreement, but how?

Reducing emissions by changing consumption of foods with large greenhouse gas emissions could have a major impact on climate change. Yet past efforts to change diets through public policy have had mixed results, suggesting that recent estimates of technical mitigation potential likely exceed feasible reductions in emissions. Shifting consumption away from livestock products is a major opportunity for reducing emissions driven by consumption demand. In some contexts, this could also provide health, food security and other environmental benefits. Packages of policy mechanisms and interventions involving health, nutrition, efficiency and sustainability in supply chains will be more effective in achieving dietary change than any one measure. Focusing on reducing food loss and waste in high potential areas and involving key value chain actors can increase returns on efforts to mitigate climate change and improve food security. Private sector investment in reducing food loss and waste requires an enabling environment, support for development of commercially viable investments, and increased awareness among financial institutions of investment opportunities. This Info Note is related to the report on "The technical mitigation potential of demand-side measures in the agri-food sector: a preliminary assessment of available measures" https://cgspace.cgiar.org/bitstream/handle/10568/77142/CCAFS%20Report%2015%20for%20web.pd

Efficacy of a skin care cream with TRPV1 inhibitor 4‐t‐butylcyclohexanol in the topical therapy of perioral dermatitis

Background Perioral dermatitis is a clinically distinctive reaction pattern of facial dermatitis, including redness, dryness, burning, pruritus and skin tightness. A gold standard treatment remains unclear. Objectives Our study evaluates the clinical value of a skin care cream with the transient receptor potential vanilloid type 1 inhibitor 4‐t‐butylcyclohexanol in POD patients over 8 weeks. Methods This open, unblinded 8‐week clinical trial included 48 patients. A skin care cream containing 4‐t‐butylcyclohexanol was applied over a period of 8 weeks. Standardized questionnaires were used at baseline, 4 and 8 weeks, for history documentation, objective and subjective severity scores, and quality of life assessments. Six different skin physiology parameters were assessed at all timepoints. Results The perioral dermatitis severity score decreased significantly during the treatment period. This was mirrored by significantly lower patients’ subjective numerical rating score and an improved quality of life score. Transepidermal water loss, stratum corneum hydration and skin erythema improved significantly during the treatment period. Conclusion This transient receptor potential vanilloid type 1 inhibitor‐based skin care cream improved subjective and objective parameters of perioral dermatitis. Decreased transepidermal water loss values and increased stratum corneum hydration demonstrate a restored skin barrier function. Consequently, the topical inhibition of these receptors is a promising management option for POD

Expression and Function of the Mannose Receptor CD206 on Epidermal Dendritic Cells in Inflammatory Skin Diseases

The capability to take up mannosylated protein antigens is important for the biologic function of dendritic cells, as many glycoproteins derived from bacteria and fungi, e.g., Malassezia furfur, are mannosylated. The expression of the mannose receptor CD206 has been regarded a differentiation hallmark of immature dendritic cells, whereas monocytes and mature dendritic cells as well as epidermal Langerhans cells do not express CD206. This study describes some epidermal dendritic cells that may express CD206 under inflammatory skin conditions: Immunohistochemical and flow cytometric analysis with the CD206-specific D547 antibody confirmed that Langerhans cells from normal human skin do not express CD206. Epidermal cell suspensions from atopic dermatitis and psoriasis revealed two distinct subsets of epidermal dendritic cells: a CD1a+++/CD206– cell population (i.e., Langerhans cells) and a CD1a+/CD206++ cell population, corresponding to the previously described inflammatory dendritic epidermal cells. CD206-mediated endocytosis, assessed by dextran-fluorescein isothiocyanate uptake, was demonstrated in inflammatory dendritic epidermal cells but not in Langerhans cells. CD206-independent uptake of the fluorescent dye Lucifer yellow, a pinocytosis marker, was demonstrated in both Langerhans cells and inflammatory dendritic epidermal cells. Electron microscopic examination, known to distinguish Langerhans cells from inflammatory dendritic epidermal cells by their Birbeck granules, revealed Langerhans cells with Birbeck granules and inflammatory dendritic epidermal cells without Birbeck granules. Inflammatory dendritic epidermal cells exhibited numerous coated pits and vesicles, the latter fusing with large endosome-like structures, thus suggesting a high endocytotic activity. Immunogold staining with D547 monoclonal antibody confirmed that inflammatory dendritic epidermal cells were positive for CD206. In conclusion, inflammatory dendritic epidermal cells but not Langerhans cells are expressing CD206 in situ and use it for receptor-mediated endocytosis

A systematic review of factors influencing treatment adherence in chronic inflammatory skin disease – strategies for optimizing treatment outcome

Adherence describes how a patient follows a medical regime recommended by a healthcare provider. Poor treatment adherence represents a complex and challenging problem of international healthcare systems, as it has a substantial impact on clinical outcomes and patient safety and constitutes an important financial burden. Since it is one of the most common causes of treatment failure, it is extremely important for physicians to reliably distinguish between non‐adherence and non‐response. This systematic review aims to summarize the current literature on treatment adherence in dermatology, focusing on chronic inflammatory skin diseases such as psoriasis, atopic dermatitis and acne. A systematic literature search was performed using the PubMed Database, including articles from 2008 to 2018. Low treatment adherence is a multidimensional phenomenon defined by the interplay of numerous factors and should under no circumstances be considered as the patient's fault alone. Factors influencing treatment adherence in dermatology include patient characteristics and beliefs, treatment efficacy and duration, administration routes, disease chronicity and the disease itself. Moreover, the quality of the physician‐patient relationship including physician‐time available for the patient plays an important role. Understanding patients’ adherence patterns and the main drivers of non‐adherence creates opportunities to improve adherence in the future. Strategies to increase treatment adherence range from reminder programs to simplifying prescriptions or educational interventions. Absolute adherence to treatment may not be realistically achievable, but efforts need to be made to raise awareness in order to maximize adherence as far as possible

Limits of agricultural greenhouse gas calculators to predict soil N2O and CH4 fluxes in tropical agriculture

Acknowledgements This work was undertaken as part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS), which is a strategic partnership of CGIAR and Future Earth. This research was carried out with funding by the European Union (EU) and with technical support from the International Fund for Agricultural Development (IFAD). The UN FAO Mitigation of Climate Change in Agriculture (MICCA) Programme funded data collection in Kenya and Tanzania. The views expressed in the document cannot be taken to reflect the official opinions of CGIAR, Future Earth, or donors. We thank Louis Bockel of the UN FAO Agricultural Development Economics Division (ESA) for his comments on an earlier draft of the manuscript.Peer reviewedPublisher PD

Mannan-Binding Lectin Levels and Activity Are Not Altered in Atopic Dermatitis Patients with a History of Eczema Herpeticum

Background. Eczema herpeticum (EH) is a potentially serious, systemic complication in subjects with atopic dermatitis (AD) caused by herpes simplex virus (HSV). The innate immune dysregulation that predisposes these subjects to cutaneous viral infections is not well understood. We tested the hypothesis that defects in mannan-binding lectin (MBL) may be associated with an increased risk of EH. Methods. We evaluated serum MBL levels and functional activity in 13 AD subjects with a history of EH (EH+) and 21 AD subjects with no history of EH (EH−). MBL levels were detected by enzyme immunoassay. MBL pathway functional activity was evaluated by determining MBL C4b deposition capacity. Results. We found no statistical difference in MBL serum levels or function between EH+ and EH− groups. Conclusion. Considering the limitations of this study (e.g., small samples size) our findings suggest that MBL defects do not play a role in EH

Recurrent eczema herpeticum – a retrospective European multicenter study evaluating the clinical characteristics of eczema herpeticum cases in atopic dermatitis patients

Background Eczema herpeticum (EH ) is a disseminated viral infection of eczematous skin disease with the herpes simplex virus. Knowledge on clinical characteristics, risk factors and recurrent disease is limited. Our aim was to better define clinical characteristics and risk factors for EH and especially for recurrent EH . Methods A retrospective analysis of EH cases assessed the history, clinical signs, prior treatment and laboratory results using a predefined questionnaire. Results A total of 224 EH cases from eight European centres were included. Extrinsic AD was identified as risk factor for EH , and only one patient suffered from intrinsic AD . Early onset of AD was identified as risk factor for recurrent EH . Pretreatment with topical steroids, systemic steroids, topical calcineurin inhibitors or plain emollients reflected standard therapy. Many patients showed AD lesions without EH , but skin without AD lesions was never affected by herpetic lesions. Conclusion Patients with clinically active, extrinsic AD are at risk of EH . Recurrent EH is associated with confounders of severe atopic distortion and requires active AD lesions for clinical manifestation. Recurrent eczema herpeticum mainly affects patients with early onset of AD