At normal conditions there is a substantial water gradient over the skin as it separates the water-rich inside of the body from the dry outside. This leads to a variation in the degree of hydration from the inside to the outside of skin and changes in this gradient may affect its structure and function. In this study we raise the question: How do changes in the water gradient across skin affect its permeability? We approach this problem in novel diffusion experiments that permit strict control of the gradient in the chemical potential of water and hence well-defined boundary conditions. The results demonstrate that a water gradient can be used to regulate transport of drugs with different lipophilic characteristics across the skin barrier. It is shown that the transport of metronidazole (log Po/w=0.0) and methyl salicylate (log Po/w=2.5) across skin increases abruptly at low water gradients, corresponding to high degrees of skin hydration, and that this effect is reversible. This phenomenon is highly relevant to drug delivery applications due to its potential of temporarily open the skin barrier for transdermal drug delivery and subsequently close the barrier after treatment. Further, the results contribute to the understanding of the occlusion effect and indicate the boundary conditions of the water gradient needed to make use of this effect

Atopic Dermatitis (AD) is a chronically relapsing skin condition characterized by dry, itchy, and inflamed skin where sufferers can frequently be subject to infections. Probiotics are known to be potent immune-modulators, and liveLactobacillus reuteriDSM 17938 has shown to be anti-inflammatory but also to possess antimicrobial and barrier function properties. This study aimed to investigate and compare two investigational ointment products (topical probiotic and control) for cutaneous acceptability, safety, and efficacy under normal conditions of use, in adult subjects with atopic dermatitis. The products were applied twice daily for 8 weeks, and cutaneous acceptability, SCORAD index, local SCORAD, and adverse events were evaluated after 4 and 8 weeks of treatment. At the end of the observations, it was demonstrated that both the probiotic-containing and probiotic-free ointments were both cutaneously acceptable and safe. It importantly showed a statistically and clinically significant improvement of the SCORAD index and local SCORAD in adult subjects with AD after 4 and 8 weeks of continuous use. In conclusion, we show evidence that the probiotic product, containing liveL. reuteriDSM 17938 as an extra ingredient, is safe and promising as a novel topical cosmetic ointment and with further testing could be a standard topical product for the management of atopic dermatitis or other disorders associated with the skin.

Introduction: Incontinence-associated dermatitis (IAD) is irritant contact dermatitis and skin damage associated with prolonged skin contact with urine and/or faeces. Identifying prognostic factors for the development of IAD may improve management, facilitate prevention and inform future research.

Methods and analysis: This protocol follows the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Prospective and retrospective observational studies or clinical trials in which prognostic factors associated with the development of IAD are described are eligible. There are no restrictions on study setting, time, language, participant characteristics or geographical regions. Reviews, editorials, commentaries, methodological articles, letters to the editor, cross-sectional and case-control studies, and case reports are excluded. MEDLINE, CINAHL, EMBASE and The Cochrane Library will be searched from inception until May 2023. Two independent reviewers will independently evaluate studies. The Quality in Prognostic Studies tool will be used to assess the risk of bias, and the Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies-Prognostic Factors checklist will be used for data extraction of the included studies. Separate analyses will be conducted for each identified prognostic factor, with adjusted and unadjusted estimated measures analysed separately. Evidence will be summarised with a meta-analysis when possible, and narratively otherwise. The Q and I2 statistics will be calculated in order to quantify heterogeneity. The quality of the evidence obtained will be evaluated according to the Grades of Recommendation Assessment, Development and Evaluation guidance.

Ethics and dissemination: No ethical approval is needed since all data is already publicly accessible. The results of this work will be published in a peer-reviewed scientific journal.

BACKGROUND: Carvone (l-carvone) is a mint-tasting flavour additive that most of us is exposed to and can cause allergic contact reactions.

OBJECTIVES: To analyse the frequency and the relevance of positive carvone reactions in a dermatitis population.

METHOD: A retrospective analysis of dermatitis patients consecutively tested with carvone from 2017 to 2021. Data were retrieved from the department's patch-test database.

RESULTS: Of 3554 patients tested with carvone, 28 (0.79%) had a positive reaction. Carvone-positive patients had higher mean age, were significantly more likely female (p < 0.001) and had often an intraoral/lip involvement (p < 0.001). In the carvone-positive group, 50% (n = 14) had a relevant reaction, and in 4 of 14, the relevance was first revealed after test reading. Of the carvone-positive patients, 18 of 28 did not have a coexisting allergy to a fragrance/flavour allergen and of these 44% had a relevant allergy.

CONCLUSIONS: The study suggests that a significant fraction of relevant carvone contact allergies may be overlooked if the allergen is not tested. Furthermore, as the exposure is widespread, inclusion of carvone in the Swedish baseline series may be justified even if the contact allergy prevalence is below 1%.

Background: The German Hairdex quality of life (QoL) instrument is specific to hair and scalp diseases, developed for self-rating and consists of 48 statements divided into five domains: Symptoms, Functioning, Emotions, Self-confidence and Stigmatisation. There was a need of a Swedish reliability tested, validated hair and scalp specific QoL instrument why the German Hairdex was chosen to be translated and reliability tested in a systematic way.

Objectives: To make a translation, a reliability test of stability, and validation of the German Hairdex QoL instrument among 100 Swedish patients with a dermatological ICD-10 diagnosis of alopecia areata (AA).

Methods: An eight-step method by Gudmundsson was used as a model with a forward and backward translation and with comments from an expert panel. A statistical test–retest (ICC (2,1)) analysis was made, followed by an internal consistency analysis. A comparison between the German and Swedish Hairdex-S constructs by a principal component analysis was performed.

Results: The Hairdex-S was very well accepted by patients. The ICC(2,1) test–retest showed a good to excellent correlation of 0.91 (CI [0.85–0.95]). Internal consistency was α = 0.92. Like the original Hairdex, Hairdex-S showed good factorability with a Kaiser–Meyer–Olkin measure of 0.82 and with one component explaining 70% of the variance: original Hairdex instrument (69%). When tested on patients with AA, the domains Functioning and Emotions had the strongest loadings, followed by Stigmatisation and Self-confidence. Younger AA patients at self-assessment and patients who reported to be younger at the onset of AA, scored statistically significantly higher on the Hairdex-S, indicating an overall lower QoL on domains Emotions and Functioning, respectively.

Conclusions: The Hairdex-S is very well accepted by AA patients, shows very good psychometric properties, and a very good agreement with the original Hairdex. The Swedish Hairdex instrument can be recommended for evaluation of patients QoL as well as for research purposes.

Hansson, L. Detektion av makrolidresistens hos Mycoplasma genitalium med Panther Fusion. Examensarbete i biomedicinsk laboratorievetenskal 15 högskolepoäng. Malmö universitet: Fakulteten för hälsa och samhälle, institutionen för Biomedicinsk Vetenskap, 2023.

Mycoplasma genitalium är en sexuellt överförbar mikroorganism som infekterar både män och kvinnor, som behandlas oftast med azitromycin med ett ökande problem av antibiotikaresistens. För M. genitalium är makrolidresistens det främsta hotet mot behandling, och har kopplats till fyra punktmutationer i region V i 23S rRNA-genen: A2071G, A2072G, A2072C samt A2071T (M. genitalium G-37, GenBank NR_077054.1). Projektet har undersökt möjligheten att ersätta nuvarande in house realtids-PCR metod för makrolidresistensbestämning med ett integrerat nukleinsyra-reningssteg och realtids-PCR med Panther Fusion (Hologic) hos Klinisk mikrobiologi i Lund. Under projektet analyserades 55 patientprover som samlades under perioden januari-februari 2023 i Region Skåne, som blivit positiva vid M. genitalium testning. Dessa prover har därefter analyserats av personal med nuvarande ABI-metod för resistensbestämning och sedan analyserats på Panther Fusion.

Nuvarande ABI-metod resulterade i positiv signal för 91% (50/55) av patientprover positiva vid M. genitalium analys och makrolidresistensmutation hos 25 % (14/55), medan Panther Fusion metoden resulterade i positiv signal för 81 % (45/55) av positiva M. genitalium prover och påvisade resistensmutation hos 20 % (11/55) av proverna.

Elevated amounts of reactive oxygen species (ROS) including hydrogen peroxide (H2O2) are observed in the epidermis in different skin disorders. Thus, epidermal sensing of H2O2 should be useful to monitor the progression of skin pathologies. We have evaluated epidermal sensing of H2O2 in vitro, by visualising H2O2 permeation through the skin. Skin membranes were mounted in Franz cells, and a suspension of Prussian white microparticles was deposited on the stratum corneum face of the skin. Upon H2O2 permeation, Prussian white was oxidised to Prussian blue, resulting in a pattern of blue dots. Comparison of skin surface images with the dot patterns revealed that about 74% of the blue dots were associated with hair shafts. The degree of the Prussian white to Prussian blue conversion strongly correlated with the reciprocal resistance of the skin membranes. Together, the results demonstrate that hair follicles are the major pathways of H2O2 transdermal penetration. The study recommends that the development of H2O2 monitoring on skin should aim for pathway-specific epidermal sensing, allowing micrometre resolution to detect and quantify this ROS biomarker at hair follicles. Graphical abstract

The aim of this study was to investigate the effect of various skin preservation protocols on in vitro drug permeation, epidermal-dermal drug distribution, and electrical impedance properties of skin membranes. Acyclovir (AC) and methyl salicylate (MS) were selected as model drugs due to their different physicochemical properties and skin metabolic profiles. In particular, AC is relatively hydrophilic (logP -1.8) and not expected to be affected by skin metabolism, while MS is relatively lipophilic (logP 2.5) and susceptible to metabolism, being a substrate for esterase residing in skin. Skin from pig ears was used and freshly excised into split-thickness membranes, which were divided and immediately stored at five different storage conditions: a) 4 °C overnight (fresh control), b) 4 °C for 4 days, c) and d) -20 °C for 6 weeks and one year, respectively, and e) -80 °C for 6 weeks. Based on the combined results, general trends are observed showing that fresh skin is associated with lower permeation of both model drugs and higher skin membrane electrical resistance, as compared to the other storage conditions. Interestingly, in the case of fresh skin, significantly lower amounts of MS are detected in the epidermis and dermis compartments, implying higher levels of ester hydrolysis of MS (i.e., higher esterase activity). In line with this, the concentration of salicylic acid (SA) extracted from the dermis is significantly higher for fresh skin, as compared to the other storage conditions. Nevertheless, for all storage conditions, substantial amounts of SA are detected in the receptor medium, as well as in the epidermis and dermis, implying that esterase activity is maintained to some extent in all cases. For AC, which is not expected to be affected by skin metabolism, freeze storage (protocols c-e) is observed to result in higher accumulation of AC in the epidermis, as compared to the case of fresh skin, while the AC concentration in dermis is unaffected. These observations can be rationalized primarily by the observed lower permeability of fresh skin towards this hydrophilic substance. Finally, a strong correlation between AC permeation and electrical skin resistance is shown for individual skin membranes irrespective of storage condition, while the corresponding correlation for MS is inferior. On the other hand, a strong correlation is shown for individual membranes between MS permeation and electrical skin capacitance, while a similar correlation for AC is lower. The observed correlations between drug permeability and electrical impedance open up for standardizing in vitro data for improved analysis and comparisons between permeability results obtained with skin stored at different conditions.

Bacterial lipopolysaccharide (LPS) induces rapid protein aggregation in human wound fluid. We aimed to characterize these LPS-induced aggregates and their functional implications using a combination of mass spectrometry analyses, biochemical assays, biological imaging, cell experiments, and animal models. The wound-fluid aggregates encompass diverse protein classes, including sequences from coagulation factors, annexins, histones, antimicrobial proteins/peptides, and apolipoproteins. We identified proteins and peptides with a high aggregation propensity and verified selected components through Western blot analysis. Thioflavin T and Amytracker staining revealed amyloid-like aggregates formed after exposure to LPS in vitro in human wound fluid and in vivo in porcine wound models. Using NF-κB-reporter mice and IVIS bioimaging, we demonstrate that such wound-fluid LPS aggregates induce a significant reduction in local inflammation compared with LPS in plasma. The results show that protein/peptide aggregation is a mechanism for confining LPS and reducing inflammation, further emphasizing the connection between host defense and amyloidogenesis.

Dry skin is a common condition that is attributed to a lack of water in the stratum corneum. With the availability of new technologies, light has been shed on the pathophysiology of dry skin at the molecular level. With the aim to discuss implications of this latest research for the optimal formulation of emollients designed to treat dry skin, five specialists met in November 2017. Research on three topics thereby provided particularly detailed new insights on how to manage dry skin: research on the lipid composition and organization of the stratum corneum, research on natural moisturizing factors, and research on the peripheral nervous system. There was consensus that latest research expands the rationale to include physiological lipids in an emollient used for dry skin, as they were found to be essential for an adequate composition and organization in the stratum corneum but are reduced in dry skin. Latest findings also confirmed the incorporation of carefully selected humectants into a topical emollient for dry skin, given the reduced activity of enzymes involved in the synthesis of moisturizing factors when skin is dry. Overall, the group of specialists concluded that the previous concept of the five components for an ideal emollient for dry skin is well in accordance with latest research.

BACKGROUND: Different specific and generic instruments are used to evaluate quality of life in dermatology, but their interrelationship is not well known. OBJECTIVES: To describe the quality of life in patients with different clinical types of psoriasis using the 36-item short form of the Medical Outcomes Study questionnaire (SF-36), and to study its correlation with dermatology-specific instruments. METHODS: We conducted a cross-sectional study of 380 inpatients with psoriasis. SF-36 mean scores were compared with the norms for medical and psychiatric disorders. Quality of life was also measured by both dermatology-specific (Skindex-29 and Dermatology Life Quality Index, DLQI) and psoriasis-specific instruments (Psoriasis Disability Index, PDI, and the Impact of Psoriasis Questionnaire, IPSO). A specific (Psoriasis Life Stress Inventory, PLSI) and a generic (12-item General Health Questionnaire, GHQ-12) measure of psychological distress was also used. A cluster analysis was performed to study the relationship among the different questionnaires. RESULTS: Our study population showed SF-36 physical health scores similar to minor medical conditions (e.g. physical functioning 79 for psoriasis, 80 for minor medical conditions, and 57 for severe medical conditions), but mental health scores quite similar to psychiatric illnesses (e.g. mental health 57 for psoriasis, 81 for minor medical conditions, 79 for severe medical conditions, and 53 for psychiatric conditions). The SF-36 showed two distinct patterns of impairment of quality of life, with a greater burden of disease for palmoplantar, pustular and arthropathic psoriasis. SF-36 scales tended to form separate clusters from the other dermatology-specific quality of life instruments. CONCLUSIONS: A generic quality of life instrument (e.g. the SF-36) provides information that is complementary to that derived from dermatological questionnaires, and may give further insight in the evaluation of the burden of psoriasis.

At normal conditions there is a substantial water gradient over the skin as it separates the water-rich inside of the body from the dry outside. This leads to a variation in the degree of hydration along the skin and changes in this gradient may affect the structure and function of skin. In this study we raise the question: How do changes in the water gradient across skin affect its permeability? We approach this problem in experiments that permit strict control of the gradient in the chemical potential of water. The results demonstrate that an external water gradient can be used to regulate transport of drugs across the skin. It is shown that the permeability of the skin barrier increases abruptly at low water gradients, corresponding to high degrees of skin hydration, and that this effect is reversible. This phenomenon is highly relevant to drug delivery applications due to its potential of temporarily opening the skin barrier for transdermal delivery of drugs and subsequently closing the barrier after treatment. The results are explained on basis that the skin is a responding membrane, for which small changes in the environment can lead to major changes in membrane structure, which in turn affect its transport properties. We have in parallel theoretical modeling and experimental studies in model systems shown how a water gradient across multilayer lipid membrane can be used as a regulating mechanism to control the barrier properties. These principles are here applied to the barrier of stratum corneum, the upper layer of the human skin, where it can provide an explanation for the experimental findings that a water gradient can be used to regulate drug transport across the skin.

The generation of reactive oxygen species presents a destructive challenge for the skin organ and there is a clear need to advance skin care formulations aiming at alleviating oxidative stress. The aim of this work was to characterize the activity of the antioxidative enzyme catalase in keratinocytes and in the skin barrier (i.e., the stratum corneum). Further, the goal was to compare the activity levels with the corresponding catalase activity found in defatted algae biomass, which may serve as a source of antioxidative enzymes, as well as other beneficial algae-derived molecules, to be employed in skin care products. For this, an oxygen electrode-based method was employed to determine the catalase activity and the apparent kinetic parameters for purified catalase, as well as catalase naturally present in HaCaT keratinocytes, excised stratum corneum samples collected from pig ears with various amounts of melanin, and defatted algae biomass from the diatom Phaeodactylum tricornutum. Taken together, this work illustrates the versatility of the oxygen electrode-based method for characterizing catalase function in samples with a high degree of complexity and enables the assessment of sample treatment protocols and comparisons between different biological systems related to the skin organ or algae-derived materials as a potential source of skin care ingredients for combating oxidative stress.