Second-degree burn induced by high-concentration topical capsaicin with mobility sequelae: A case report

High-concentration topical capsaicin is used as a second-line treatment for neuropathic pain. Transient, mild burning sensation and erythema are expected adverse drug reactions. Here, we report the first case of second degree burn after the application of a high-concentration topical capsaicin patch with secondary mobility sequelae. Nine months after the application, neuropathic pain still remained and the patient described mobility difficulties in daily activities, preventing her from returning to work. This report aims to raise the question of the benefit/risk ratio of high concentration topical capsaicin.     

Autosomal dominant inheritance with sex-limited manifestation: An unusual mode of transmission in humans and animals

Autosomal dominant, sex-limited inheritance is a distinct mode of transmission that should not be conflated with X-linked inheritance. From animal studies, we know that sex-limited inheritance implies the chance to “turn off” some genes in either males or females, in order to meliorate the phenotype, for example, by improving the fecundity. In this way, sex-limited genes play an important role in the evolution of diverse species of animals. In human genetics, however, the biological significance of sex-limited genes is unknown until today. When screening the literature, we found, thus far, three human examples of sex-limited transmission. Autosomal dominant, male-limited inheritance has meticulously been studied in a particular form of precocious puberty. Limitation to females was described in autosomal dominant lymphedema of the CESLR1 type, being underpinned by convincing molecular findings. Another example is white lentiginosis of Grosshans that shows clinical evidence of such mode of transmission although molecular findings are lacking as yet. In the animal kingdom, autosomal dominant sex-limited inheritance is a well-established phenomenon that has extensively been studied in various species such as butterflies, damselflies, fish (cichlids), and birds. Hence, at this point in time, it seems likely that other human examples of this mode of inheritance have previously been reported or will be published in the future.     

Status quo and future perspectives of molecular diagnostics in dermatology

Molecular diagnostics (MDx) has become an indispensable pillar of diagnostics in dermatology. Modern sequencing technologies allow for identification of rare genodermatoses, analysis of somatic mutations in melanoma are prerequisite for targeted therapies, and cutaneous infectious pathogens are quickly detected by PCR and other amplification methods. However, to push innovation in molecular diagnostics and tackle so far unmet clinical needs, research activities need to be bundled and the pipeline from idea to MDx product clearly rolled out. Only then, the requirements for technical validity and clinical utility of novel biomarkers can be fulfilled and the long-term vision of personalized medicine will be realized.     

Carboxylic Groups via Postpolymerization Modification of Polythiophene and their Influence on the Performance of a Polymeric MALDI Matrix

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) requires a matrix, and traditionally small organic matrices (SOMs) carrying acidic or basic functional groups are used. However, the analyte ionization via secondary processes in the gas-phase seems to be more important than primary processes. For conjugated polymeric matrices, an even more complicated picture emerges due to their apolar and aprotic nature, high molecular weight, and low tendency to desorb. Poly(3-dodecylthiophene-2,5-diyl) (P3DDT), a good matrix for low-molecular weight (LMW) analytes, does not give matrix-related peaks in the LMW area. Here, carboxylic acid ( COOH) side-chains are introduced via postpolymerization modification. The polymers are characterized by NMR, FT-IR, CV, MALDI MS, and, when possible, GPC. The electron withdrawing side-chains serve three functions; i) raising the ionization potential (IP), ii) improving the absorption maximum, and iii) acting as a source of protons. When measuring basic amines, this results in the occurrence of additional [Analyte + H⁺]⁺ signals compared to polymers without acidic groups, where only radical cations [Analyte]^+• are detected. Similarly, estradiol and testosterone, compounds with high IPs, are not detected by polythiophenes without acidic groups, while P3DDT-COOH enables detection as protonated species.     

Biomarkers associated with the development of comorbidities in patients with atopic dermatitis: A systematic review

Biomarkers associated with the development of comorbidities in atopic dermatitis (AD) patients have been reported, but have not yet been systematically reviewed. Seven electronic databases were searched, from database inception to September 2021. English language randomized controlled trials, prospective and retrospective cohort, and case–control studies that investigated the association between a biomarker and the development of comorbidities in AD patients were included. Two authors independently screened the records for eligibility, one extracted all data, and critically appraised the quality of studies and risk of bias. Fifty six articles met the inclusion criteria, evaluating 146 candidate biomarkers. The most frequently reported biomarkers were filaggrin mutations and allergen specific-IgE. Promising biomarkers include specific-IgE and/or skin prick tests predicting the development of asthma, and genetic polymorphisms predicting the occurrence of eczema herpeticum. The identified studies and biomarkers were highly heterogeneous, and associated with predominately moderate-to-high risk of bias across multiple domains. Overall, findings were inconsistent. High-quality studies assessing biomarkers associated with the development of comorbidities in people with AD are lacking. Harmonized datasets and independent validation studies are urgently needed.