Single-cell transcriptomics reveals a senescence-associated IL-6/CCR6 axis driving radiodermatitis

Irradiation‐induced alopecia and dermatitis (IRIAD) are two of the most visually recognized complications of radiotherapy, of which the molecular and cellular basis remains largely unclear. By combining scRNA‐seq analysis of whole skin‐derived irradiated cells with genetic ablation and molecular inhibition studies, we show that senescence‐associated IL‐6 and IL‐1 signaling, together with IL‐17 upregulation and CCR6⁺‐mediated immune cell migration, are crucial drivers of IRIAD. Bioinformatics analysis colocalized irradiation‐induced IL‐6 signaling with senescence pathway upregulation largely within epidermal hair follicles, basal keratinocytes, and dermal fibroblasts. Loss of cytokine signaling by genetic ablation in IL‐6^−/− or IL‐1R^−/− mice, or by molecular blockade, strongly ameliorated IRIAD, as did deficiency of CCL20/CCR6‐mediated immune cell migration in CCR6^−/− mice. Moreover, IL‐6 deficiency strongly reduced IL‐17, IL‐22, CCL20, and CCR6 upregulation, whereas CCR6 deficiency reciprocally diminished IL‐6, IL‐17, CCL3, and MHC upregulation, suggesting that proximity‐dependent cellular cross talk promotes IRIAD. Therapeutically, topical application of Janus kinase blockers or inhibition of T‐cell activation by cyclosporine effectively reduced IRIAD, suggesting the potential of targeted approaches for the treatment of dermal side effects in radiotherapy patients.

Isolated solar angioedema: A systematic review of the literature

Solar urticaria is a well-recognized photodermatosis, sometimes accompanied by angioedema. However, isolated solar angioedema (ISA) is a rare and unrecognized entity. The purpose of our work was to systematically review the available data on ISA. Therefore, a systematic review of studies evaluating ISA was performed. Additionally, a case of a 21-years-old patient from our photodermatosis service is presented. The search yielded 421 publications, with 3 eligible for review. Together with our case, 5 cases were included overall. All patients were female. Four out of 5 patients first experienced ISA at childhood or early adulthood (age range 6-22 years). UVA photoprovocation was positive in the 3 out of the 4 patients who were tested. Improvement was noted following NB-UVB hardening (2 out of 5 patients) or a short course of oral prednisone (3 out of 5 patients) combined with regular sunscreen application. To conclude, ISA is an extremely rare entity, although it may be underdiagnosed due to lack of awareness. The clinician must consider ISA in the differential diagnosis of angioedema since it can have a detrimental effect on quality of life. Besides sun avoidance, there is no consensus regarding treatment.

Self-administered daylight-activated photodynamic therapy for the treatment of hand eczema: A prospective proof-of-concept study

Photodynamic therapy (PDT), traditionally used in patients with nonmelanoma skin cancer, has been found to be effective for various inflammatory skin conditions. Daylight-activated PDT (DL-PDT), in which the sun serves as the light source, is substantially less painful than conventional PDT. This study aimed to determine the safety and efficacy of DL-PDT in a series of patients with chronic hand eczema (CHE). A proof-of-concept prospective design was used. Eight patients diagnosed with CHE at a tertiary dermatology clinic underwent DL-PDT. The first treatment was administered at the clinic and subsequent treatments (up to four total) were self-administered at home at 2-week intervals. Outcome was evaluated with the Investigator Global Assessment (IGA; score 0-4), Dermatology Life Quality Index (DLQI; score 0-24), and blinded review of clinical photographs (graded on a quartile scale by percent improvement). There were six male and two female patients of mean age 35 years. All underwent at least three treatments. The IGA score improved by 2.5 points at 1 month, 2.7 at 3 months, and 2.2 at 6 months post-treatment, and the DLQI score improved by 7.9, 6.6, and 6.1 points, respectively. Clinical photograph grades improved by 2.9 points at 3 months. Side effects were mild and transient. All patients had some degree of recurrence after 6 months of treatment. The self-administered DL-PDT is easy to perform, moderately effective, and safe to use in patients with CHE. Repeated treatments might be required to maintain remission.

Real-life experience in the treatment of solar urticaria: retrospective cohort study

BACKGROUND

Solar urticaria (SU) is a rare photodermatosis causing a significant impact on patients' quality of life (QoL), and treatment is often challenging.

AIM

To analyse clinical experience with a tailored stepwise therapeutic approach.

METHODS

A retrospective cohort design was used. Patients with suspected SU underwent laboratory investigations and photoprovocation. Those with a high minimal urticaria dose (MUD) were treated with a single antihistamine (protocol 1), and those with a lower MUD received three types of antihistamines (protocol 2); both protocols included a leucotriene receptor antagonist (LRA). In cases of failure, treatment was switched to omalizumab at doses of < 300 mg/month with incremental dosage increases as necessary (monthly dose range, 150-600 mg/month). Symptom relief and photoprovocation under treatment were evaluated.

RESULTS

In total, 30 patients (10 men, 20 women) were enrolled. Most (87%) were sensitive to visible light (1-70 J/cm² ) with or without extension to ultraviolet A. Of the 30 patients, 23 opted for our stepwise approach: 22 achieved complete remission on protocols 1 or 2 (n = 17) or after switching to omalizumab (n = 5), and another patient achieved partial remission under omalizumab. There were no treatment-related severe adverse effects.

CONCLUSIONS

Symptoms of SU can be well controlled by treatment with antihistamines and an LRA tailored to the degree of photosensitivity, followed by omalizumab in refractory cases. This has important implications for patient QoL.

Daylight photodynamic therapy for the treatment of actinic cheilitis

BACKGROUND

Actinic cheilitis (AC) is a common, chronic premalignant condition resulting from protracted sun exposure affecting the vermilion border of the lower lip. Treatment of AC aims at terminating the progression to squamous cell carcinoma by obliterating the primary lesion, and includes ablative methods; nonablative modalities such as cryotherapy, electrodessication, chemical peeling, topical imiquimod and 5-fluorouracil; and photodynamic therapy (PDT). Daylight-activated PDT, in which natural daylight serves as the light source, showed promising results in the treatment of actinic keratoses with substantially less pain than conventional PDT.

PURPOSE

To determine the safety and efficacy of daylight PDT in a series of patients with AC.

METHODS

Eleven patients with AC were treated with daylight PDT. All patients underwent repeated treatment sessions until clinical and histological remission were achieved.

RESULTS

Cure rate was 91% (10 of 11 patients, three females/eight males; mean age 59.2 ± 14.4 years). Mean number of treatments to attain cure was 2.7. Patients experienced mild erythema and minimal to no pain during treatment.

CONCLUSIONS

Daylight PDT is a promising modality for the treatment of AC, with impressive cosmetic results and few side effects.

Palmar Telangiectasias: A Cutaneous Sign for Smoking

BACKGROUND

Telangiectasias are permanent dilations of blood capillaries which appear in a variety of medical conditions. Cutaneous palmar telangiectasias have been postulated to be associated with smoking.

OBJECTIVE

To determine whether a significant correlation exists between palmar telangiectasias and smoking habits.

PATIENTS AND METHODS

A total of 124 volunteers participated in this observational study by allowing physical evaluation of their palms and by completing a questionnaire.

RESULTS

Palmar telangiectasias were found to be associated with current or past smoking. Neither age nor gender was found to be a co-contributor.

DISCUSSION

Palmar telangiectasias were found to constitute highly specific and sensitive markers for prolonged smoking.

Integrated cooling-vacuum-assisted 1540-nm erbium:glass laser is effective in treating mild-to-moderate acne vulgaris

Acne treatment by a mid-infrared laser may be unsatisfactory due to deeply situated acne-affected sebaceous glands which serve as its target. Skin manipulation by vacuum and contact cooling may improve laser-skin interaction, reduce pain sensation, and increase overall safety and efficacy. To evaluate the safety and efficacy of acne treatment using an integrated cooling-vacuum-assisted 1540-nm erbium:glass laser, a prospective interventional study was conducted. It included 12 patients (seven men and five women) suffering from mild-to-moderate acne vulgaris. The device utilizes a mid-infrared 1540-nm laser (Alma Lasers Ltd. Caesarea, Israel), which is integrated with combined cooling-vacuum-assisted technology. An acne lesion is initially manipulated upon contact by a vacuum-cooling-assisted tip, followed by three to four stacked laser pulses (500-600 mJ, 4 mm spot size, and frequency of 2 Hz). Patients underwent four to six treatment sessions with a 2-week interval and were followed-up 1 and 3 months after the last treatment. Clinical photographs were taken by high-resolution digital camera before and after treatment. Clinical evaluation was performed by two independent dermatologists, and results were graded on a scale of 0 (exacerbation) to 4 (76-100 % improvement). Patients' and physicians' satisfaction was also recorded. Pain perception and adverse effects were evaluated as well. All patients demonstrated a moderate to significant improvement (average score of 3.6 and 2.0 within 1 and 3 months, respectively, following last treatment session). No side effects, besides a transient erythema, were observed. Cooling-vacuum-assisted 1540-nm laser is safe and effective for the treatment of acne vulgaris.

Lymphatic Dissemination in Cutaneous Leishmaniasis Following Local Treatment

Cutaneous leishmaniasis (CL) is diverse in its clinical presentation but usually demonstrates an erythematous, infiltrated, ulcerated, and crusted papule or nodule in exposed areas of the body. Rare clinical features have been reported including lymphatic dissemination, usually with subcutaneous nodules along lymphatic channels. Herein, we present six patients suffering from Old World CL with lymphatic dissemination characterized by sporotrichoid subcutaneous nodules along the lymphatic channels draining the primary lesion. Patients' history, clinical and laboratory findings were collected and summarized. Lymphatic dissemination of CL in our patients manifested as subcutaneous nodules without epidermal involvement within the axis of lymphatic drainage toward the regional lymph node, at times accompanied by regional lymphadenopathy. In all patients, the lymphatic dissemination was not present at initial diagnosis of CL, appearing only after local (topical or intralesional) treatment was initiated. In three patients, the subcutaneous nodules resolved without systemic treatment. Lymphatic dissemination of Old World CL is not uncommon and may possibly be triggered by local treatment. It should be recognized by dermatologists, especially those working in endemic areas. Systemic treatment may be not necessary since spontaneous resolution may occur.

Cutaneous leishmaniasis responds to daylight-activated photodynamic therapy: proof of concept for a novel self-administered therapeutic modality

BACKGROUND

Cutaneous leishmaniasis (CL) is endemic in Israel, with hundreds of new cases reported in recent years. Photodynamic therapy (PDT) is highly effective for treatment of CL, but requires equipment available only at specialized centres. Daylight-activated PDT (DA-PDT) abolishes the need for artificial light sources and allows the patient to administer the treatment with no professional assistance.

OBJECTIVES

The objective of this single-centre, open study was to establish proof of concept for the efficacy of DA-PDT in the treatment of CL using clinical, microbiological and molecular clearance as outcome measures.

METHODS

Thirty-one patients with CL (11 Leishmania major and 20 Leishmania tropica) underwent DA-PDT. Fourteen patients were treated in the hospital garden under professional supervision and 17 patients underwent DA-PDT as a self-administered treatment modality at home. Following application of a thick layer of 16% methyl aminolaevulinate and 30-min occlusion, the lesions were exposed to daylight for 2·5 h. Treatment sessions were repeated at weekly intervals until clinical and microbiological cure. Control lesions were either treated with cryotherapy or left untreated.

RESULTS

The overall cure rate for DA-PDT was 89% (intention-to-treat cure rate 77%); this was 86% for the hospital-based treatment group and 92% for the self-administered group.

CONCLUSIONS

DA-PDT proved to be effective in the treatment of CL caused by L. major and L. tropica. More patients were treated according to a self-administered protocol, suggesting that DA-PDT can be adopted even in technologically deprived countries where the majority of Leishmania infections are encountered.

Late-onset onchocercal skin disease among Ethiopian immigrants

BACKGROUND

Onchocerciasis is an infectious disease caused by the filaria Onchocerca volvulus. Very little is known regarding onchocerciasis imported from endemic to nonendemic areas.

OBJECTIVES

To evaluate pruritic dermatitis simulating atopic dermatitis in Ethiopian immigrants in Israel.

PATIENTS AND METHODS

A retrospective study of 27 Ethiopian immigrants to Israel was conducted. Demographics and clinical and laboratory data were collected.

RESULTS

Of the group of 27 patients, 10 (37%) were men and 17 (63%) were women. The average age at referral was 29 years. All of the patients emigrated from Kuwara, Ethiopia. Diagnosis was done by either positive skin snip test or immunoglobulin (Ig) G4 serology of onchocerciasis in 14 patients. The most common presentation was a combination of lichenified onchodermatitis with atrophy and depigmentation (36%). Eosinophilia and elevated IgE levels were common. Seventeen patients were treated with a single administration of oral ivermectin 200 μg mg(-1). Thirteen patients responded to the treatment.

CONCLUSIONS

Immigrants from endemic regions to developed countries presenting with pruritic diseases, especially those with a clinical picture suggestive of atopic dermatitis, should be evaluated for possible onchocerciasis infection. Ivermectin, a relatively safe and low-cost treatment, should be considered even in the absence of a proven disease. Physicians should have a high index of suspicion in patients with the corresponding residential history.

Thiazolidinedione derivatives as novel agents against Propionibacterium acnes biofilms

AIMS

The aim of the present study was to determine the effect of two thiazolidinedione derivatives on Propionibacterium acnes biofilm formation in vitro and to assess their effect on the susceptibility of P. acnes biofilms towards antimicrobials.

METHODS AND RESULTS

The compounds were shown to have a moderate to strong antibiofilm activity when used in subinhibitory concentrations. These compounds do not affect P. acnes attachment but lead to increased dispersal of biofilm cells. This dispersal results in an increased killing of the P. acnes biofilm cells by conventional antimicrobials.

CONCLUSION

The antibiofilm effect and the effect on biofilm susceptibility of the thiazolidinedione-derived quorum sensing inhibitors were clearly demonstrated.

SIGNIFICANCE AND IMPACT OF THE STUDY

Propionibacterium acnes infections are difficult to treat due to the presence of biofilms at the infection site and the associated resistance towards conventional antimicrobials. Our results indicate that these thiazolidinedione derivatives can be promising leads used for the treatment of P. acnes infections and as anti-acne drugs.

Weather conditions and daylight-mediated photodynamic therapy: protoporphyrin IX-weighted daylight doses measured in six geographical locations

BACKGROUND

Photodynamic therapy (PDT) is an attractive therapy for nonmelanoma skin cancers and actinic keratoses (AKs). Daylight-mediated methyl aminolaevulinate PDT (daylight-PDT) is a simple and painless treatment procedure for PDT. All daylight-PDT studies have been performed in the Nordic countries. To be able to apply these results in other parts of the world we have to compare the daily protoporphyrin IX (PpIX) light dose in other countries with the PpIX light doses found in Nordic countries.

OBJECTIVES

  To calculate where and when daylight-PDT of AKs was possible in six different geographical locations using ground stations measuring PpIX-weighted daylight doses.

METHODS

  PpIX-weighted daylight doses were measured using a dosimeter with a customer-specific photodiode with a detector sensitivity that mimics the PpIX absorption spectrum and measures in 'PpIX doses'. The dosimeters were built into ground stations that were placed in six geographical locations measuring from July to December 2008. Temperature data for each location were obtained from the internet. The maximal ultraviolet (UV) index for Copenhagen was obtained for the measuring period of the dosimeters.

RESULTS

  If the PpIX light dose should be above 8Jcm(-2) and the maximum temperature of the day at least 10°C, it was possible to treat patients on nearly all days until the middle of September in Reykjavik and Oslo, until the last week of October in Copenhagen and Regensburg, until the middle of November in Turin and all year in Israel.

CONCLUSIONS

  Where and when to perform daylight-PDT depends on the PpIX light dose and outdoor temperature. The PpIX light dose was influenced by the geographical location (latitude), weather condition and time of year. The UV index was not more suitable than temperature and weather to predict if the intensity of daylight would be sufficient for daylight-PDT.

Synthesis and evaluation of thiazolidinedione and dioxazaborocane analogues as inhibitors of AI-2 quorum sensing in Vibrio harveyi

Two focused libraries based on two types of compounds, that is, thiazolidinediones and dioxazaborocanes were designed. Structural resemblances can be found between thiazolidinediones and well-known furanone type quorum sensing (QS) inhibitors such as N-acylaminofuranones, and/or acyl-homoserine lactone signaling molecules, while dioxazaborocanes structurally resemble previously reported oxazaborolidine derivatives which antagonized autoinducer 2 (AI-2) binding to its receptor. Because of this, we hypothesized that these compounds could affect AI-2 QS in Vibrio harveyi. Although all compounds blocked QS, the thiazolidinediones were the most active AI-2 QS inhibitors, with EC(50) values in the low micromolar range. Their mechanism of inhibition was elucidated by measuring the effect on bioluminescence in a series of V. harveyi QS mutants and by DNA-binding assays with purified LuxR protein. The active compounds neither affected bioluminescence as such nor the production of AI-2. Instead, our results indicate that the thiazolidinediones blocked AI-2 QS in V. harveyi by decreasing the DNA-binding ability of LuxR. In addition, several dioxazaborocanes were found to block AI-2 QS by targeting LuxPQ.

Detection of living Sarcoptes scabiei larvae by reflectance mode confocal microscopy in the skin of a patient with crusted scabies

Scabies is an intensely pruritic disorder induced by a delayed type hypersensitivity reaction to infestation of the skin by the mite Sarcoptes scabiei. The diagnosis of scabies is established clinically and confirmed by identifying mites or eggs by microscopic examination of scrapings from the skin or by surface microscopy using a dermatoscope. Reflectance-mode confocal microscopy is a novel technique used for noninvasive imaging of skin structures and lesions at a resolution compatible to that of conventional histology. Recently, the technique was employed for the confirmation of the clinical diagnosis of scabies.We demonstrate the first ever documentation of a larva moving freely inside the skin of a patient infected with scabies.

Direct antifungal effect of femtosecond laser on Trichophyton rubrum onychomycosis

Onychomycosis is caused by dermatophyte infection of the nail. Though laser energy has been shown to eliminate dermatophytes in vitro, direct laser elimination of onychomycosis is not successful due to difficulties in selectively delivering laser energy to the deeper levels of the nail plate without collateral damage. Femtosecond (fsec) infrared titanium sapphire lasers circumvent this problem by the nonlinear interactions of these lasers with biological media. This quality, combined with the deeply penetrating nature of the near-infrared radiation, allows elimination of deeply seeded nail dermatopytes without associated collateral damage. Nail cuttings obtained from patients with onychomycosis caused by Trichophyton rubrum underwent fsec laser irradiation using increasing laser intensities with the focus scanned throughout the whole thickness of the nail specimen. The efficacy of the laser treatment was evaluated by subculture. Scanning electron microscopy was used to determine fsec laser-induced collateral damage. We found that a fsec laser fluence of 7 x 10(31) photons m(-2) s(-1) or above successfully inhibited the growth of the fungus in all samples examined, whereas laser intensities above 1.7 x 10(32) photons m(-2) s(-1) affected the structure of the nail plate. Our findings suggest that T. rubrum-mediated onychomycosis may be treated by fsec laser technology.

RIN2 deficiency results in macrocephaly, alopecia, cutis laxa, and scoliosis: MACS syndrome

Inherited disorders of elastic tissue represent a complex and heterogeneous group of diseases, characterized often by sagging skin and occasionally by life-threatening visceral complications. In the present study, we report on an autosomal-recessive disorder that we have termed MACS syndrome (macrocephaly, alopecia, cutis laxa, and scoliosis). The disorder was mapped to chromosome 20p11.21-p11.23, and a homozygous frameshift mutation in RIN2 was found to segregate with the disease phenotype in a large consanguineous kindred. The mutation identified results in decreased expression of RIN2, a ubiquitously expressed protein that interacts with Rab5 and is involved in the regulation of endocytic trafficking. RIN2 deficiency was found to be associated with paucity of dermal microfibrils and deficiency of fibulin-5, which may underlie the abnormal skin phenotype displayed by the patients.

Fluorescence imaging for the demarcation of basal cell carcinoma tumor borders

BACKGROUND

Basal cell carcinoma (BCC) is a common malignancy accounting for 80% of all nonmelanoma skin cancers. Mohs micrographic surgery (MMS) is considered superior to alternative treatments, but the procedure is time consuming and costly. Alternative simpler techniques to facilitate accurate tumor demarcation are therefore in demand. Fluorescence imaging following application of 5-aminolevulinic acid is a noninvasive diagnostic technique that gives rapid information about the superficial extent of the skin tumor.

OBJECTIVE

To ascertain whether fluorescence imaging improves the clinical tumor border assessment by investigating the consistency between tumor size determination by MMS, clinical assessment, and fluorescence imaging.

METHODS

Eighteen patients with histologically verified nodular BCCs on the face scheduled for MMS were included in the study. The night before the surgical procedure, 5-aminolevulinic methyl ester cream was applied to the lesion. The following morning, tumor borders were determined clinically (clinical size), after illumination with Wood's light (fluorescence size), and by the tumor defect left on the skin surface following removal of the MMS specimen (Mohs size).

RESULTS

The median tumor sizes were 93.05 mm2 (Mohs size), 61.05 mm2 (clinical size), and 72.75 mm2 (fluorescence size). The interclass correlation coefficients between Mohs size and fluorescence size was 0.984 and Mohs size and clinical size was 0.752.

CONCLUSION

Tumor border estimation by fluorescence imaging and clinical assessment underestimate the genuine tumor size determined by MMS; however, the fluorescence size showed a higher degree of consistency with the Mohs size than did the clinical size.

Genomic-scale analysis of psoriatic skin reveals differentially expressed insulin-like growth factor-binding protein-7 after phototherapy

BACKGROUND

Phototherapy is an effective therapy for psoriasis. The molecular mechanisms underlying its efficacy are not yet understood.

OBJECTIVES

To compare the expression profiles of psoriatic epidermis in patients before and after undergoing phototherapy with the purpose of expounding the molecular mechanisms underlying the efficacy of this therapeutic modality.

METHODS

Patients with psoriasis were investigated before and after full courses of phototherapy: three patients completed 3 weeks of heliotherapy at the Dead Sea; three patients received narrowband ultraviolet B (NB-UVB) for a total of 20-27 treatments. Epidermal samples were analysed using oligonucleotide microarrays. Our microarray results led us to explore further and to quantify a specific gene, insulin-like growth factor-binding protein-7 (IGFBP7), using real-time quantitative reverse transcriptase-polymerase chain reaction assays and immunohistochemical protein expression.

RESULTS

We identified 315 genes modulated by phototherapy: the expressions of 248 genes (142 up; 106 down) were changed by Dead Sea treatment, 116 (71 up; 45 down) by NB-UVB and 49 (37 up; 12 down) were modulated regardless of treatment. The differentially changed genes include S100 calcium-binding proteins, dendritic cell markers, tumour necrosis factor-alpha target genes, matrix metalloproteinases and NFkappaB target genes. We also found that IGFBP7 mRNA and protein were significantly underexpressed in psoriatic compared with normal epidermis, and that phototherapy significantly increased their expression.

CONCLUSIONS

IGFBP7 is underexpressed in psoriatic epidermis but is inducible by UVB.

Onchocerciasis--river blindness

Onchocerciasis results from infestation by the nematode Onchocerca volvulus and is characterized by troublesome itching, skin lesions, and eye manifestations. Although partially controlled by international mass prevention programs, onchocerciasis remains a major health hazard and is endemic in Africa, Arabia, and the Americas. Onchocerciasis is spread by bites from infested black flies, which transmit larvae that subsequently develop into adult filariae. Skin symptoms are commonly nonspecific and include severe pruritus, acute and chronic dermatitis, vitiligo-like hypopigmentation, and atrophy. Onchocercal ocular disease covers a large spectrum of manifestations, which in severe cases, may lead to blindness. Diagnosis is usually made by direct visualization of the larvae emerging from superficial skin biopsies, "skin snips." In some cases, the microfilariae can also be directly observed at the slit lamp when migrating into the anterior chamber of the eye. Ivermectin is, at present, the drug of choice for skin and ocular manifestations. Recent research using a chemotherapeutic approach that targets filarial Wolbachia symbionts in the treatment and control of onchocerciasis, however, suggests that 100 mg/d of doxycycline for 6 weeks might be effective in reducing the filarial load and preventing ocular symptoms.

The UVB-induced gene expression profile of human epidermis in vivo is different from that of cultured keratinocytes

In order to obtain a comprehensive picture of the molecular events regulating cutaneous photodamage of intact human epidermis, suction blister roofs obtained after a single dose of in vivo ultraviolet (UV)B exposure were used for microarray profiling. We found a changed expression of 619 genes. Half of the UVB-regulated genes had returned to pre-exposure baseline levels at 72 h, underscoring the transient character of the molecular cutaneous UVB response. Of special interest was our finding that several of the central p53 target genes remained unaffected following UVB exposure in spite of p53 protein accumulation. We next compared the in vivo expression profiles of epidermal sheets to that of cultured human epidermal keratinocytes exposed to UVB in vitro. We found 1931 genes that differed in their expression profiles between the two groups. The expression profile in intact epidemis was geared mainly towards DNA repair, whereas cultured keratinocytes responded predominantly by activating genes associated with cell-cycle arrest and apoptosis. These differences in expression profiles might reflect differences between mature differentiating keratinocytes in the suprabasal epidermal layers versus exponentially proliferating keratinocytes in cell culture. Our findings show that extreme care should be taken when extrapolating from findings based on keratinocyte cultures to changes in intact epidermis.

Role of antioxidants in prevention of pyrimidine dimer formation in UVB irradiated human HaCaT keratinocytes

The objective of the present study was to study the role of reactive oxygen species (ROS) in UVB induced cyclobutane pyrimidine dimer (CPD) formation in human keratinocytes, and to examine the modulating activity of low molecular weight antioxidants. To demonstrate the involvement of ROS, we examined the protective capacity of alpha-tocopherol, tempamine, and diethyldithiocarbamate (DDC) on CPD formation in intact cells and naked DNA. HaCaT cells and naked DNA in water solution were irradiated with UVB in the presence of the antioxidants and CPD was determined by ELISA. We found that all three antioxidants provided protection against UVB induced CPD formation. The protection was observed in intact cells only and not in naked DNA. Since some of the tested antioxidants do not possess UV absorbing qualities, our findings suggest that in a cellular environment ROS play a role in CPD formation.

Ultraviolet A-1 as a treatment for ulcerative lichen planus of the feet

Ulcerative lichen planus of the feet is a rare variant of lichen planus characterized by the constellation of a chronic bullous and ulcerative eruption limited to the feet, atrophy of involved skin and nails, and cicatricial alopecia. Only split-thickness skin grafting has here to been documented to be effective. We here report a case with ulcerative lichen planus of the feet successfully treated with medium-dose ultraviolet A-1.

Porphyra-334, a potential natural source for UVA protective sunscreens

The mycosporine-like amino acid (MAA), porphyra-334 (lambda(max) = 334 nm; epsilon = 42,300 M(-1) cm(-1)), was isolated from the aquatic cyanobacterium Aphanizomenon flos-aquae (AFA) and its structure was verified by spectroscopic methods. The UVA absorption properties of the crude methanolic extract were determined against two commercial sun care products in terms of mean critical wavelength, mean UVA/UVB ratios and UVA protection category (Boots the Chemists, Ltd.). The crude methanolic extract from AFA exhibited maximum UVA protection comparable to that determined for Boots SPF 4.

The Region of 150 kb Telometic to HLA-C Is Associated with Psoriasis in the Jewish Population

The HLA-Cw*0602 has been associated with psoriasis in different ethnic groups. But, it remains unclear whether HLA-C is the PSORS1 gene (the psoriasis gene in the MHC). Thus, several case-control studies have been performed in order to investigate whether HLA-C itself determines the susceptibility to the disease. We studied 59 Jewish patients with type I psoriasis and 79 matched controls. Polymorphic genes and markers from HLA-B (centromeric to HLA-C) to the corneodesmosin (CDSN) gene (telomeric to HLA-C) were genotyped in order to determine their contribution to the susceptibility to psoriasis. Neither HLA-Cw*0602 nor the allele CDSN*TTC were significantly associated with psoriasis with the size of the sample studied. The genes and markers telomeric to HLA-C such as the microsatellite C1_4_4 (OR = 2.6, 95% CI = 1.4-4.7, p(c) = 0.018) the octamer transcription factor (OTF)-3 gene (OR = 2.6, 95% CI = 1.6-4.3, p(c) = 0.0001) and the alpha-helix coiled-coil rod homologue (HCR) gene (OR = 2.5, 95% CI = 1.3-4.5, p(c) = 0.004), however, were associated with the disease. These results suggest that a major psoriasis susceptibility gene is likely to be located within a region of 150 kb telomeric to HLA-C and centromeric to the CDSN gene.

Molecular detection of MART-1, tyrosinase and MIA in peripheral blood, lymph nodes and metastatic sites of stage III/IV melanoma patients

Melanoma lesions that develop in the same patient at different times or simultaneously at different locations may differ antigenically, because malignant melanoma is heterogeneous in terms of its biological, immunological and metastatic properties. The objective of this study was to characterize the molecular profiles of melanoma cells in peripheral blood, lymph nodes and metastatic tissues, employing the messenger RNA (mRNA) expression of tyrosinase, melanoma-inhibiting activity (MIA) and melanoma antigen recognized by T cells-1 (MART-1) as markers. Samples of cells propagated from metastatic sites were obtained from 17 stage III/IV melanoma patients and assayed by reverse transcriptase-polymerase chain reaction (RT-PCR), using specific primers for each marker. In eight patients, marker profiles were analysed in simultaneously obtained specimens of peripheral blood, lymph nodes and metastatic tissues originating from the same patient. Tyrosinase, MIA and MART-1 were expressed in 59%, 76% and 76% of the metastases, respectively. Simultaneously obtained specimens of peripheral blood, lymph nodes and metastatic tissues showed a high degree of homogeneity: 60%, 75% and 20% for tyrosinase, MIA and MART-1, respectively. Our findings suggest that the rather homogeneous expression pattern found in different tumour sites analysed in the same patient is of potential prognostic and therapeutic importance. Furthermore, melanoma lesions may be negative for the expression of antigens such as MART-1, and discrepancies in expression patterns between peripheral blood and metastatic tissues may occur, especially for this marker. Finally, our findings support the notion that molecular screening using an RT-PCR approach is appropriate in this kind of investigation.

Gene expression profiling of in vivo UVB-irradiated human epidermis

BACKGROUND

Several recent studies have employed microarray profiling to study UVB-regulated gene expression in human skin. These studies are all based on UV-irradiated cultured cells that differ substantially from the intact tissues they are supposed to imitate. The purpose of the present study was to analyze the differential expression of UVB-regulated genes in intact human epidermis following in vivo UV irradiation.

METHODS

The forearms of human volunteers were exposed to 4 MED of UVB in vivo, followed by removal of epidermal samples from exposed and non-exposed areas after 24 h. RNA samples were analyzed using oligonucleotide microarray (Affymetrix) technology analyzing 12 500 genes simultaneously. Verification of selected genes was performed by semi-quantitative reverse transcriptase polymerase chain reaction.

RESULTS

Gene expression patterns clearly distinguished UV-exposed epidermis from unexposed skin. Classification of these genes into functional categories revealed that several biological processes are globally affected by UVB. Significant changes were seen in more than 800 genes.

CONCLUSION

Human intact epidermis responds to a single low dose of in vivo UVB irradiation by differential regulation of numerous genes. Our results illustrate the power of global gene expression analysis of human epidermis to identify molecular pathways involved in UV-induced photodamage.

Photoprotection by Cichorum endivia extracts: prevention of UVB-induced erythema, pyrimidine dimer formation and IL-6 expression

In the gradual process of evolution, plants have developed natural sun protecting substances that enable continuous survival under direct and intense ultraviolet (UV) radiation. As part of our studies of plant-derived pigments that might constitute an alternative to conventional sunscreens, we have tested the ethanolic extracts of roots, stalks, and inflorescences of populations of wild Cichorum endivia subsp. Divaricatum (Asteraceae) in terms of protection against sunburn, and in prevention of UVB-induced pyrimidine dimer formation and IL-6 mRNA expression in the human keratinocyte cell line, HaCaT. Using ELISA technique for detection of pyrimidine dimers and RT-PCR for detection of IL-6, we found that the ethanolic extract of C. endivia roots absorbs radiation in the UVB spectrum and partially prevents induction of pyrimidine dimers and IL-6 expression. Application of the root extract on the skin prior to UVB irradiation totally prevented erythema. Our findings suggest that C. endivia extracts might possess sun-protective qualities that make them useful as sunscreens.

Diagnostic performance and retention of acquired skills after dermatology elective

BACKGROUND

The dermatology elective often constitutes the future physician's only exposure to dermatologic practice. Cost-benefit considerations dictate that the elective enables the students to acquire useful diagnostic expertise in the short time period available, and that this expertise is not rapidly forgotten after completion of the elective.

METHODS

In order to determine the efficacy of a 2-week dermatology elective in promoting diagnostic skills and to ascertain the preservation of the acquired expertise, kodachrome slide-based multiple-choice examinations were administered to 84 sixth year medical students at the beginning (pre-test) and completion (post-test) of the elective. The long-term retention of diagnostic skills was evaluated by re-testing 4-9 months after completion of the elective (follow-up test).

RESULTS

The mean scores of correct answers at the pre- and post-test were 39.73% and 72.46%, respectively. The mean score at the follow-up test for students with a previous dermatology elective was 80.22%, compared with a score of 46.00% for students who did not participate in the elective.

CONCLUSIONS

The 2-week dermatology elective significantly improved the diagnostic skills of the participants, and the knowledge obtained during the elective was retained for at least 4-9 months.

A new UV-B absorbing mycosporine with photo protective activity from the lichenized ascomycete Collema cristatum

A novel photo protective mycosporine was isolated from the lichenized ascomycete Collema cristatum. Biological activity was measured in terms of protection against UV-B induced membrane destruction and pyrimidine dimer formation in cultured human keratinocytes, and prevention of UV-B induced erythema. It was found that the pure isolated compound prevented UV-B induced cell destruction in a dose-dependent manner, that the compound partially prevented pyrimidine dimer formation and completely prevented UV-B induced erythema when applied to the skin prior to irradiation.

Onchocerciasis among Ethiopian immigrants in Israel

BACKGROUND

Onchocerciasis results from infestation by the nematode Onchocerca volvulus, and is characterized clinically by troublesome itching, skin lesions and eye manifestations. Since 1992, approximately 9,000 immigrants have arrived in Israel from the Kuwara province of northwest Ethiopia where the prevalence of onchocerciasis is particularly high.

OBJECTIVES

To determine whether onchocerciasis is the cause of cutaneous and ocular symptoms among recent immigrants from the Kuwara province in Ethiopia.

METHODS

We examined 1,200 recent immigrants from the Kuwara province residing at the Mevasseret Zion immigration center outside Jerusalem. Among them, patients with cutaneous signs suggestive of onchocerciasis underwent a skin-snip biopsy and a thorough eye examination.

RESULTS

In the detailed skin examination performed in 83 patients, the most common skin finding was chronic papular onchodermatitis, found in more than 46 patients (55%); depigmentation and atrophy was found in 13 (15%) and 12 (14%), respectively. In 40 patients (48%), living microfilaria were detected in their skin snips. Of the 65 patients who underwent a through eye examination, 45 patients (66%) had ocular complaints. Corneal abnormalities were found in 55 of the 130 eyes (42%), active anterior segment intraocular inflammation and live microfilariae were found in 4 eyes (3%) and lens changes in 16 eyes (1%). Eleven eyes (9%) showed retinal or choroidal changes.

CONCLUSIONS

Skin and eye manifestations associated with onchocerciasis are prevalent among symptomatic Ethiopians who immigrated to Israel from the Kuwara province.

[Cutaneous leishmaniasis]

Leishmaniasis is a vector-borne disease caused by an obligate intracellular protozoa, Leishmania, which resides in macrophages. The parasite is transmitted by an infected female sandfly. The incidence of cutaneous leishmaniasis approaches 2 million new cases per year with 90% of the cases occurring in the "Old World", while the "New World" accounts for the rest. Infection may be restricted to the skin with development of characteristic ulcers, or may affect the mucous membranes in its mucocutaneous form. The clinical diagnosis is verified by the presence of amastigotes in slit-skin smears. Therapeutic modalities include systemic treatments such as the pentavalent antimony compound sodium stibogluconate, liposomal formulations of amphotericin B, oral ketoconazole or itraconazole, as well as topical paromomycin sulphate, local heat, freezing with liquid nitrogen, or photodynamic therapy. An effective vaccine is not available.

[Onchocerciasis]

Onchocerciasis is an infestation caused by the nematode, Onchocerca volvulus, and characterized by eye manifestations, skin lesions and troublesome itching. Although partially controlled by international mass treatment programs, onchocerciasis remains a major health hazard in endemic areas in Africa, Arabia, and the Americas. Onchocerciasis is spread by bites from infested blackflies which transmit larvae that subsequently develop into adult filariae. Skin findings are commonly non-specific, and include severe pruritus, acute and chronic dermatitis, vitiligo-like hypopigmentation and atrophy. Onchocercal ocular disease has a large spectrum of manifestations and may even lead to blindness. Diagnosis is usually made by direct visualization of the larvae emerging from superficial skin biopsies, "skin snips". In some cases, the microfilariae can also be directly observed with a slit lamp when they migrate into the anterior chamber of the eye. Ivermectin is highly microfilaricidal, and is the current drug of choice for both skin and ocular manifestations.

Achievements of dermatological research in Denmark and Israel: a comparative 10-year study

Wide differences of achievement in dermatological research between Denmark and Israel have been reported, although the two countries are comparable in terms of academic dermatological structure. The aims of the present study were to document these differences by means of bibliometric analysis, and to attempt to elucidate the causes of these differences. Employing MEDLINE searches for the 10-year period 1988-97, quantitative and qualitative comparisons of the dermatological publications from these two countries were conducted. We found the achievements of Danish dermatological research to be superior to those of Israel, and suggest that the large proportion of case reports and reviews is one cause of the relatively low ranking of Israeli dermatological research efforts.

Expression of tyrosinase, MIA and MART-1 in sentinel lymph nodes of patients with malignant melanoma

BACKGROUND

Regional lymph node status is an important predictor of survival in patients with malignant melanoma. Mapping of sentinel lymph nodes using sensitive molecular techniques has recently been introduced. Malignant melanoma is heterogeneous in terms of its biological, immunological and metastatic properties, and melanoma cells exhibit a polymorphous expression of tumour markers. Thus, assays that include multiple markers appear to be more sensitive than single-marker assays.

OBJECTIVES

To characterize the molecular profiles of melanoma cells in sentinel lymph nodes employing the mRNA expression of tyrosinase, MIA and MART-1 as markers.

METHODS

Samples of sentinel lymph nodes from 17 melanoma patients and 18 control nodes from non-melanoma patients were assayed by reverse transcriptase-polymerase chain reaction, using specific primers for each marker.

RESULTS

We found that both tyrosinase and MIA expression were sensitive indicators of micrometastases in sentinel lymph nodes that were negative on routine histopathological examination, and that the finding of micrometastases expressing MART-1 in sentinel lymph nodes was negatively correlated with overall survival.

CONCLUSIONS

Characterization of the molecular profiles of melanoma cells constitutes a valid means of detecting metastatic melanoma cells in sentinel lymph nodes, and of predicting the survival of melanoma patients.

Polymorphism in MICA rather than HLA-B/C genes is associated with psoriatic arthritis in the Jewish population

The aim of this study was to examine whether the association of psoriatic arthritis (PsA) with human leukocyte antigen (HLA) class I genes is secondary to linkage disequilibrium with a nearby gene. We examined a sample of the Jewish population to investigate whether HLA-B/C and DR polymorphism is associated with susceptibility, or whether other closely related class I loci, such as the major histocompatibility complex class I chain-related gene A (MICA) and tumor necrosis factor (TNF), might play a role in disease development. Comparisons of different populations with different HLA profiles would be of value in identifying the candidate genes involved in PSA. Fifty-two patients with PsA and 73 random matched controls from a Jewish population were selected and DNA typed by polymerase chain reaction-single-strand oligonucleotide probe (PCR-SSOP) (HLA-C), PCR sequence-specific primers (PCR-SSP) (HLA-B, -DR), radioactive PCR (MICA-TM polymorphism in the transmembrane region), and PCR-RFLP (TNF). Some findings can be concluded from the study: (1) the frequency of HLA-B*5701, B*3801, B*39, B*27, Cw*0602, Cw*07, DRB1*0402, and DRB1*0701 were not found to be significantly increased in PsA; (2) no significant differences of TNFalpha promoter alleles at positions -308 and -238 were found between PsA and healthy controls; (3) the trinucleotide repeat polymorphism MICA-A9 was present at a higher frequency in PsA patients, (p(c) < 0.009, RR = 3.34, EF = 0.39); and (4) MICA-A9 polymorphism was found in linkage disequilibrium with HLA-B alleles (B*5701, B*3801) described to be associated with PsA in Caucasians. These results suggest that the MICA gene or other nearby gene(s) may be involved in the development of PsA, and it would thus appear that psoriasis vulgaris (PsV) and PsA are associated with different MHC susceptibility genes.