Skin reactions to irritants assessed by non-invasive bioengineering methods

Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants.     

Analysis of mast cell subpopulations (MCT, MCTC) in cutaneous inflammation using novel enzyme-histochemical staining techniques

Abstract In order to gain insights into the dynamics of mast cell subpopulations in normal and diseased skin, a novel enzyme-histochemical double and triple staining method was employed that allowed the detection of metachromasia (toluidine blue) and the mast cell proteases tryp-tase and chymase within the same cell. Cryostat sections were used of skin biopsies from the following specimens: normal skin (N=4), psoriasis (N=13), atopic eczema (N=7), lichen planus (N=6), interferon α2a injection sites (N=l) of a leukemic infiltrate and corresponding normal skin of the same patient before and after treatment. (i) Equal numbers of tryptase-and chymase-positive mast cells (MCTC) were obtained in all normal and diseased specimens in papillary and reticular dermis, with threefold increases around appendages, (ii) Tryptase-positive mast cells (MCT) were absent in normal skin, but were markedly increased in a disease-specific pattern within the papillary dermis, the inflammatory infiltrate and around appendages, (iii) Marked increases of MCT were also noted at interferon injection sites within the leukemic infiltrate, but not in the normal skin of the same patient. These data suggest that disease-dependent mast cell dynamics involve only MCT in cutaneous inflammation and that MCT numbers are controlled by distinct, disease-specific local tissue factors.     

Keratin expression in pilosebaceous epithelia in truncal skin of acne patients

Summary This study compared the pattern of keratin expression in pilosebaceous follicles in uninvolved trunk skin of acne patients, comedones, and normal control skin by immunohistochemistry. using both immunofluorescent (IF) and immunoperoxidase (IP) techniques. The shape, size and gross morphology of truncal follicles varied greatly. There was no difference in keratin expression between normal skin and uninvolved skin of patients with acne. The upper part of the pilosebaceous duct expressed keratins K1, K5, K10 and K14, whereas the lower duct expressed keratins K5, K6, K14, K16, K17 and Kl9. The sebaceous gland showed considerable heterogeneity in keratin expression, with some lobules expressing keratins K1, K5, K7, K10, K14 and K17. The comedone wall showed a pattern of keratin expression similar to that of the upper follicle, except that there was, in addition, expression of keratins K6 and K16 suprabasally, and panepithelial expression of K17 in the comedone wall. IF techniques were found to be less sensitive than the IP method in the detection of individual keratins, but the use of multiple antibodies and many different transverse and longitudinal sections of follicles permitted full conclusions to be made. The increased expression of keratins K6, K16 and K17 in the comedone wall is likely to represent a secondary effect of increased cell turnover due to the primary underlying mechanism of comedogenesis. which is as yet unknown.     

基于Joinpoint回归和年龄-时期-队列模型分析中国皮肤癌的长期发病趋势

  目的  分析中国皮肤癌的发病趋势并分别估计其年龄、时期、队列效应。  方法  从2019年全球疾病负担研究中估计中国皮肤癌发病率的变化趋势。采用Joinpoint回归分析模型分析年度变化百分比和平均年度变化百分比(average annual percentage change, AAPC);利用年龄-时期-队列模型评估年龄、时期和出生队列效应对皮肤癌发病率的影响。  结果  1990―2019年中国皮肤癌男性和女性年龄标准化发病率均上升。Joinpoint回归分析模型分析显示皮肤恶性黑色素瘤男性AAPC为2.8%(95% CI: 2.6~3.0),女性AAPC为3.0%(95% CI: 2.8~3.2);基底细胞癌男性AAPC为4.2%(95% CI: 3.9~4.4),女性AAPC为4.0%(95% CI: 3.7~4.3);鳞状细胞癌男性AAPC为3.7%(95% CI: 3.5~3.9),女性AAPC为2.9%(95% CI: 2.7~3.0)。此外,年龄-时期-队列模型表明无论男女,皮肤癌的发病风险均随年龄增长和年份推移而增加,且较晚出生的队列的发病风险均低于之前出生的队列。  结论  1990―2019年中国皮肤癌的发病率呈上升趋势,年龄越大、出生越早且生活在当代的人其发病风险更高。应重视皮肤癌的防治工作。     

COVID-19 vaccine safety during pregnancy in women with systemic lupus erythematosus

COVID-19 vaccination has been shown to be safe in patients with systemic lupus erythematosus (SLE), but data on vaccine-associated adverse events (AEs) during the antenatal and lactation period are scarce or lacking. We investigated COVID-19 vaccination-related AEs in pregnant SLE patients from the COVAD study, a global esurvey involving 157 collaborators from 106 countries. A total of 9201 complete responses were extracted. Among 6787 (73.8%) women, we identified 70 (1.1%) who were exposed to at least one COVID-19 vaccine dose during pregnancy, 11 with SLE. Delayed onset (>7 days) vaccine-related AEs were triangulated with disease activity, treatment changes due to flare after vaccination, and COVID-19 infections in vaccinated pregnant women. Health-related quality of life and physical function was recorded using PROMIS. Age of patients ranged from 28 to 39 years; 5/11 women were of Asian origin. None of these patients reported major vaccine AEs or change in the status of their autoimmune disease. Although minor AEs were common, they did not impair daily functioning, and the symptoms resolved after a median of 3 (IQR: 2.5–5.0) days. All patients reported good to excellent health status. No adverse pregnancy outcomes were reported. Importantly, none of the patients reported thrombotic events post-vaccination, which provides reassurance in a patient population with a high risk for cardiovascular comorbidity and thrombosis, especially in the presence of antiphospholipid antibodies or the antiphospholipid syndrome, a considerable portion of SLE patients. Our findings provide reassurance and can contribute to informed decisions regarding vaccination in patients with SLE and high-risk pregnancies due to their background autoimmune disease. The risk/benefit ratio of COVID-19 vaccination appears favourable, with vaccines both providing passive immunisation to the fetus and active immunisation to the mother with no signals of exacerbation of the mother's autoimmune disease.     

Sneddon-wilkinson disease and arthritis

Sneddon-Wilkinson disease (subcorneal pustular dermatosis) is an uncommon disorder. An unusual association with seronegative arthritis is reported with review of literature.     

Compression and walking versus bed rest in the treatment of proximal deep venous thrombosis with low molecular weight heparin

OBJECTIVE: The purpose of this randomized controlled trial was to evaluate the benefits of compression and walking exercises in comparison with bed rest in the acute stage of proximal deep venous thrombosis (DVT). METHODS: Forty-five patients with proximal DVT that was proved with compression ultrasound scan or phlebography were randomized into three groups. Group A consisted of 15 patients who received inelastic compression bandages (Unna boots on the lower leg, adhesive bandages on the thigh), and group B consisted of 15 patients who received thigh-length compression stockings, class II. Group C consisted of 15 patients who underwent bed rest and no compression. All patients received dalteparin, 200 IU/kg per body weight, subcutaneously every 24 hours. The clinical characteristics of the three groups were comparable. Primary end points were the reduction of pain assessed daily with the Visual Analogue Scale and the Lowenberg test, the reduction of leg circumference at the ankle and calf levels, and the improvement of clinical scores. The daily walking distance was measured with a pedometer. Safety parameters were ventilation-perfusion scans and duplex ultrasound scans performed on days 0 and 9. RESULTS: The daily walking distance was between 600 and 12,000 m in the compression groups and averaged 66 m in the bed rest group. The pain level showed a statistically significant reduction starting after the second day in the compression groups (A and B) and after 9 days in the bed rest group C (P <.05). The same was true for the measurement of leg circumference. Improvement of the clinical scores was significantly better in the compression groups compared with the bed rest group (P <.01). There was no significant difference concerning the occurrence of new pulmonary emboli and regression of thrombus diameter. Progression of thrombi in the femoral vein was greater and occurred more frequently in the bed rest group than in the other two groups (P = not significant). CONCLUSION: Mobile patients with acute proximal DVT treated with low molecular weight heparin should be encouraged to walk with compression bandages or medical compression stockings. The rate of resolution of pain and swelling is significantly faster when the patient ambulates with compression. The risk of pulmonary embolism is not significantly increased by this approach.     

Skin sensitivity and skin microbiota: Is there a link?

Sensitive skin is defined by the occurrence of unpleasant sensations, accompanied or not by erythema, in response to stimuli which normally should not provoke such sensations and that cannot be linked to skin disease. Even if its pathophysiology is not completely known, hyper‐reactivity of the cutaneous nervous system associated with an abnormal skin barrier has been hypothesized as a primary culprit including more recently a role of the cutaneous microbiota. The objective of this short review is to discuss the relationship between the skin microbiota, skin sensitivity and the skin barrier function.