Maarten M. Verberk

Loss-of-function polymorphisms in the filaggrin gene are associated with an increased susceptibility to chronic irritant contact dermatitis: a case-control study.

Background  Polymorphisms in the filaggrin (FLG) gene, which result in loss of filaggrin production, may alter the skin barrier and are a well‐known predisposing factor for atopic dermatitis.

Percutaneous penetration of sodium lauryl sulphate is increased in uninvolved skin of patients with atopic dermatitis compared with control subjects

Background  Involved regions of the skin in patients with atopic dermatitis (AD) have been shown to have higher transepidermal water loss (TEWL), indicating a compromised skin barrier. Whether uninvolved skin also has diminished barrier characteristics is controversial.

Stratum corneum cytokines and skin irritation response to sodium lauryl sulfate

Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24‐hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3‐week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)‐1α decreased by 30% after repeated exposure, while IL‐1RA increased 10‐fold and IL‐8 increased fourfold. Baseline IL‐1RA and IL‐8 values were predictors of TEWL and erythema after single exposure (r = 0.55–0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL‐1RA and IL‐8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.

Cytokine gene polymorphisms and susceptibility to chronic irritant contact dermatitis

Background:  Cytokines play an important role in skin inflammation.

Increased permeability for polyethylene glycols through skin compromised by sodium lauryl sulphate

Abstract:  In this in vivo human study we assessed the influence of skin damage by sodium lauryl sulphate (SLS) on percutaneous penetration of polyethylene glycols (PEGs) of different molecular weights (MW).

Cytokines at different stratum corneum levels in normal and sodium lauryl sulphate‐irritated skin

Background/purpose: Cytokines play an important role in inflammatory and repair processes occurring in the skin. The objectives of this study were to determine the amounts of cytokines and protein isolated by tape stripping in the different layers of the stratum corneum (SC), and to compare normal skin with skin exposed in vivo to the irritant sodium lauryl sulphate (SLS).

Smoking habits and levels of lead and cadmium in blood in urban women.

SummaryIn 222 Dutch urban women lead (PbB)- and cadmium (CdB)-levels in blood were measured and related to smoking habits. PbB ranged from 40 ppb to 240 ppb and CdB rangedfrom 0.2 ppb to 4.4 ppb. Smokers had slightly higher PbB-levels and distinctly higher CdB-levels.

Validity of biological tests in epidemiological toxicology

SummaryThe authors emphasize the need to introduce the concept of validity (sensitivity and specificity) of biological test methods in epidemiological toxicology (occupational and public health). Up till now too often relevant information is lost, because the frequency distribution of individual data is not taken into account. The method of calculating parameters of validity is demonstrated. These parameters add relevant information for determining the feasibility of test methods; they provide valuable information not presented by classical statistical treatment of data. Several examples have been worked out to elucidate the approach.

Differential cytokine expression in skin after single and repeated irritation by sodium lauryl sulphate

Abstract:  In vivo levels of cytokines and presence of neutrophils and eosinophils in skin irritation are not well known. Our objective was to get more insight in inflammatory mediators and markers involved in single and repeated skin irritation. We sampled epidermis‐derived fluid using a novel technology that includes application of a negative pressure on the skin after creation of micropores in the stratum corneum by a laser. In nine volunteers, transdermal fluid was sampled after a single 4‐h 10% sodium lauryl sulphate exposure and a repeated 3‐week exposure (0.1% sodium lauryl sulphate). Twenty‐seven cytokines were assessed by multiplex assay, and IL‐1α, eosinophil cationic protein and myeloperoxidase by enzyme‐linked immunosorbent assay. Levels of eosinophil cationic protein were increased after irritation and correlated with levels of myeloperoxidase. The levels of inflammatory mediators showed large interindividual differences in unexposed and exposed skin. Despite this variation, several mediators clearly showed increased levels: CC chemokine ligand (CCL)11, CXCL10 and vascular endothelial growth factor after both single and repeated exposure, IL‐1α and basic fibroblast growth factor after single exposure and interleukin‐1 receptor antagonist (IL‐1RA) after repeated exposure. After repeated exposure, CCL5 and the ratio IL‐1RA/IL‐1α both increased compared with single exposure. We conclude that single and repeated irritation induces differential and concerted expression of various inflammatory mediators and markers.

Chronic solvent-induced encephalopathy: European consensus of neuropsychological characteristics, assessment, and guidelines for diagnostics

INTRODUCTION The presence of neuropsychological impairment is a hallmark of chronic solvent-induced encephalopathy (CSE), and using clinical neuropsychological procedures to generate a valid assessment of the condition is crucial for its diagnosis. The goals of this consensus document are to provide updated knowledge of the neuropsychological characteristics of CSE and to provide internationally acceptable guidelines for using neuropsychological assessments in the process of diagnosing patients who are suspected of having CSE. MATERIALS AND METHODS A European working group that was composed of experts in the field of the clinical diagnosis of CSE met at several round-table meetings and prepared this report. The first section of the consensus paper addresses a review of the relevant literature that was published between 1985 and March 2012. The second section addresses recommendations for the clinical neuropsychological assessment of patients who are suspected of having CSE. RESULTS The literature review indicates that the most common neuropsychological impairments in CSE patients are within the domains of attention, particularly the speed of information processing, memory, and motor performance. It appears that the influence of CSE on memory processes mainly involves immediate recall and generally involves verbal, visual and visuospatial material. In the second section, six recommendations are presented regarding important functional domains for the neuropsychological diagnostic process of CSE that relate to the evaluation of neuropsychological impairment, the assessment and evaluation of symptoms, differential diagnostic considerations, the reliability and validity of neuropsychological test results, and the retesting of patients. DISCUSSION AND CONCLUSIONS These recommendations will contribute to the improvement of the process for accurately diagnosing CSE, better counselling for CSE patients, the comparability of epidemiological data between countries, and finally, by raising awareness, these recommendations will contribute to combating the adverse health effects of occupational exposure to solvents.