Skin of atopic dermatitis patients shows disturbed ß-glucocerebrosidase and acid sphingomyelinase activity that relates to changes in stratum corneum lipid composition.

Patients with Atopic Dermatitis (AD) suffer from inflamed skin and skin barrier defects. Proper formation of the outermost part of the skin, the stratum corneum (SC), is crucial for the skin barrier function. In this study we analyzed the localization and activity of lipid enzymes ß-glucocerebrosidase (GBA) and acid sphingomyelinase (ASM) in the skin of AD patients and controls. Localization of both the expression and activity of GBA and ASM in the epidermis of AD patients was altered, particularly at lesional skin sites. These changes aligned with the altered SC lipid composition. More specifically, abnormal localization of GBA and ASM related to an increase in specific ceramide subclasses [AS] and [NS]. Moreover we related the localization of the enzymes to the amounts of SC ceramide subclasses and free fatty acids (FFAs). We report a correlation between altered localization of active GBA and ASM and a disturbed SC lipid composition. Localization of antimicrobial peptide beta-defensin-3 (HBD-3) and AD biomarker Thymus and Activation Regulated Chemokine (TARC) also appeared to be diverging in AD skin compared to control. This research highlights the relation between correct localization of expressed and active lipid enzymes and a normal SC lipid composition for a proper skin barrier.

Changes in cell-cycle kinetics responsible for limiting somatic growth in mice.

In mammals, the rate of somatic growth is rapid in early postnatal life but then slows with age, approaching zero as the animal approaches adult body size. To investigate the underlying changes in cell-cycle kinetics, [methyl-H]thymidine and 5'-bromo-2'deoxyuridine were used to double-label proliferating cells in 1-, 2-, and 3-wk-old mice for four weeks. Proliferation of renal tubular epithelial cells and hepatocytes decreased with age. The average cell-cycle time did not increase in liver and increased only 1.7 fold in kidney. The fraction of cells in S-phase that will divide again declined approximately 10 fold with age. Concurrently, average cell area increased approximately 2 fold. The findings suggest that somatic growth deceleration primarily results not from an increase in cell-cycle time but from a decrease in growth fraction (fraction of cells that continue to proliferate). During the deceleration phase, cells appear to reach a proliferative limit and undergo their final cell divisions, staggered over time. Concomitantly, cells enlarge to a greater volume, perhaps because they are relieved of the size constraint imposed by cell division. In conclusion, a decline in growth fraction with age causes somatic growth deceleration and thus sets a fundamental limit on adult body size.

Squamous cell carcinoma arising in hypertrophic lichen planus.

Hypertrophic lichen planus (HLP) is a chronic T-cell-mediated inflammatory disease characterised by pruritic hypertrophic or verrucous plaques on the lower limbs. We report a case of an 87-year-old woman with a 12-year history of HLP on both lower legs presenting with malignant transformation of one lesion into a squamous cell carcinoma (SCC). Malignancy developing in cutaneous lichen planus is rare, with less than 50 cases reported in the literature. This case highlights the need to be aware of suspicious changes in long-standing HLP to allow early detection of a developing SCC.

[Rosacea fulminans in pregnancy]. / Een zwangere vrouw met een rode uitslag in het gelaat.

We present a 38-year-old woman who suddenly developed erythema with follicular papules and pustules on her face during the second trimester of pregnancy. The diagnosis 'rosacea fulminans' was made. This is an uncommon skin condition that predominantly affects younger women. Treatment with erythromycin was successful.

[Pyoderma gangrenosum following breast surgery]. / Pyoderma gangrenosum na mammachirurgie.

Pyoderma gangrenosum is a rare, destructive ulcerative condition of the skin. The painful ulcers may occur spontaneously, or result from a minor injury or surgery. The clinical presentation can mimic a necrotizing bacterial infection; however, no micro-organisms can be cultured from the skin lesions and the ulcers fail to respond to antibiotic therapy. Surgical interventions can aggravate the disease process. We describe 2 patients, a 22-year-old woman and a 45-year-old woman, with ulcerative wound abnormalities after breast surgery. After failure of antibiotic therapy and standard wound care, tissue biopsy of the wounds confirmed the clinical diagnosis 'pyoderma gangrenosum'. Wound healing began after systemic steroid treatment. Delays in diagnosis and treatment of pyoderma gangrenosum may result in extensive ulceration and scarring. It is, therefore, important to recognise the characteristic clinical features at an early stage and to start appropriate treatment immediately.