New Cryopreservation Technology of hMSCs: First Preclinical Results Using DMSO-containing Medium

BACKGROUND

Human mesenchymal stem cells (hMSCs) have tremendous potential in regenerative medicine, making it desirable to cryopreserve and bank them to increase their access and availability.

OBJECTIVE

This research is part of a clinical trial performed on six patients that aimed to use advanced therapy medicinal products (ATMPs) based on hMSCs in patients undergoing repeated total hip replacement.

MATERIALS AND METHODS

To compare the characteristics of fresh and frozen hMSCs, we used the trypan blue exclusion test (cell viability), flow cytometry (cell viability and phenotyping), sterility determinations and the clonogenic assay of cell proliferation.

RESULTS

Cryopreserved hMSCs showed good quality parameters after thawing in comparison with fresh hMSCs in suspension. When using a medium containing dimethyl sulfoxide (DMSO), the viability was higher than 90% in all cases. The cell purity determined by flow cytometry was also acceptable.

CONCLUSION

These initial results show that the prepared cryopreserved ATMP exhibited good viability and phenotype characteristics.

Low wintertime pre-diagnostic vitamin D status is associated with an increased risk of internal malignancies in kidney transplant recipients

Low serum 25-hydroxyvitamin D (25OHD) concentrations have been associated with increased cancer risk, but the relative importance of seasonality, i.e. high summer concentrations versus low winter concentrations, is unclear. We investigated this issue in a high risk group: kidney transplant recipients with known increased risk of cancer and low vitamin D statuses. We examined the relationship between registered concentrations of 25OHD binned by quarter and subsequent risk of internal malignancy or cutaneous squamous cell carcinoma in 1112 kidney transplant recipients. Hazard ratios for internal malignancies were significantly increased with lower pre-diagnostic 25OHD concentrations in the first quarter of the year (January-March); a 1.4 fold increase (95%CI 1.1;1.7) per 10 nmol L-1 decrease in 25OHD. Except for women in April-June (1.3 (1.01;1.7) per 10 nmol L-1 decrease) pre-diagnostic 25OHD concentrations in the other quarters were not statistically significantly associated with internal malignancies. Higher 25OHD concentrations tended to be associated with the development of cutaneous squamous cell carcinomas, independent of the time of the year. Our study indicates that low wintertime 25OHD concentrations are associated with an increased risk of internal malignancies and that transplant recipients may benefit from wintertime vitamin D supplementation. Our findings need further corroboration, but suggest that the lowest concentrations of vitamin D, which occur in winter, are important for the risk of internal malignancies.

A Qualitative Gas Chromatographic Analysis of Substituted 5,6-Dihydroxyindoles from the Urine of Patients with Melanoma

A qualitative gas chromatographic analysis of trimethylsilylated ethyl acetate extracts of melanotic urine revealed 5 indolic compounds, which have been identified as substituted 5,6-dihydroxyindoles. Ethyl acetate extracts of melanotic urines at pH 2.0 contained isomeric 5-hydroxy-6-methoxy and 6-hydroxy-5-methoxy-indolyl-2-carboxylic acids which were not separable under the conditions used. A careful hydrolysis of melanotic urine with a Helix pomatia preparation followed by extraction at pH 6.5 in a nitrogen atmosphere released 3 additional indolic compounds from their conjugated form. Using gas chromatographic-mass spectrometric analysis they were identified as 5-hydroxy-6-methoxy, 6-hydroxy-5-methoxyindole and 5,6-dihydroxyindole.

Chloroquine treatment reduces the number of cutaneous HLA-DR+ and CD1a+ cells in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can be exacerbated by exposure to ultraviolet radiation (UVR). The number and phenotype of antigen presenting cells in the skin play a role in cutaneous immune response generation. Although antimalarials are widely used in SLE treatment, their mode of action is not completely elucidated. The aim of our study was to determine the effect of chloroquine treatment on HLA-DR+ and CD1a+ cell number in locally irradiated (three minimal erythema doses of UVB) and normal appearing skin in SLE patients and healthy subjects. A significantly higher number of HLA-DR+ and CD1a+ cells were found in both locations in SLE patients compared with controls. Following three months of daily chloroquine treatment (250 mg), the HLA-DR+ and CD1a+ cell counts were significantly reduced in both irradiated and unirradiated sites of SLE patients, although still higher than in controls. Chloroquine treatment reduces the number of antigen presenting cells in the skin of SLE patients, and this effect may explain the antimalarials beneficial immunoregulatory and anti-inflammatory properties.

The effects of a mid-winter 8-week course of sub-sunburn sunbed exposures on tanning, vitamin D status and colds

Like UV irradiation, which generates vitamin D(3) in the skin, the hormonally active metabolite, 1,25-dihydroxyvitamin D(3), boosts innate immunity against viruses and bacteria. Epidemiologic studies have found high vitamin D levels to be associated with lower risk of infections of the upper respiratory tract (colds). We have therefore performed an intervention study in 105 young adults (ages 18-30 years; 91% female) over a mid-winter 8-week period (January-March 2010). The participants were randomised to 3 groups: (A) subjected to 3 times a week sub-sunburn sunbed exposure (n = 35), (B) daily vitamin D supplementation, @ 1000 IU (n = 37), and (C) a control group without any intervention (n = 33). The mean serum level of 25-hydroxyvitamin D (25(OH)D) dropped from 62 to 55 nmol l(-1) in group C, while these levels rose from 62 to 109 and from 58 to 93 nmol l(-1) in groups A and B, respectively (p < 0.001). The skin on the chest darkened significantly in group A (mean difference in lightness, L*, equalled -5.7, p < 0.001), correlating significantly, but weakly, with increases in 25(OH)D (3.3 nmol l(-1) per unit drop in L*, R(2) = 0.17, p = 0.014). The percentage of self-reported colds with proper signs and symptoms was only slightly and not significantly reduced in groups A and B in comparison to group C: 57 and 51 versus 67%, respectively. Hence, the sub-sunburn sunbed treatment was effective in tanning and increasing the 25(OH)D serum level, more so than 1000 IU per day, but had no appreciable effect on colds.

Mutations in EGFR signal pathway in correlation with response to treatment of head and neck cancers

The prognostic and predictive value of the epidermal growth factor receptor (EGFR) expression and some genetic alterations in an EGFR signal pathway, such as the EGFR amplification, the EGFR activating tyrosine kinase domain mutations or the k-ras gene mutation were investigated in our study. The aim of the research was to evaluate the occurrence of the above-mentioned biomarkers in correlation with a therapeutic response and survival in patients with locoregionally advanced spinocellular head and neck cancers.

KEYWORDS

Head and neck cancer, EGFR, predictive marker, k-ras, EGFR amplification, EGFR tyrosine kinase domain mutation.

Prevention and treatment of vitamin D deficiency in Dutch psychogeriatric nursing home residents by weekly half-body UVB exposure after showering: a pilot study

BACKGROUND

in older people, induction of cutaneous vitamin D production by ultraviolet B (UVB) exposure may be preferable to oral supplementation: it cannot cause toxic levels, it helps to prevent polypharmacy and, moreover, there are indications that UVB exposure has beneficial effects on health and well being by mechanisms other than the vitamin D pathway alone.

OBJECTIVE

the aim of this pilot study is to investigate whether weekly, half-body, UVB irradiation after showering can increase serum 25-hydroxyvitamin D (25(OH)D) to sufficient levels, in a Dutch psychogeriatric nursing home population.

METHOD

subjects were eight psychogeriatric nursing home patients, mean age: 79 ± 8. Exclusion criteria were going outdoors into the sun more than once a week, the presence of actinic or cancer skin lesions and known resistance to body contact. The intervention consisted of weekly half-body UVB irradiation, after showering, over 8 weeks, with 0.5 minimal erythemal dose (MED). Main outcome measures were change in fasting serum levels of 25(OH)D and parathyroid hormone (PTH) at 0, 2, 4 and 8 weeks.

RESULTS

at baseline, mean serum 25(OH)D was 28.5 nmol/l. Mean serum 25(OH)D levels increased to 46.5 nmol/l. Median serum PTH levels decreased by 20% after 8 weeks of treatment.

CONCLUSION

an 8 week course of weekly, frontal half-body irradiation with UVB, at 0.5 MED, leads to an significant increase in 25(OH)D serum levels, but this period is too short to reach vitamin D sufficiency.

The susceptibility of dermatophytes to photodynamic treatment with special focus on Trichophyton rubrum

Owing to the accessibility of skin to light, many applications of photodynamic treatment (PDT) have been developed within dermatology. The recent increase of dermatological antimicrobial PDT investigations is related to the growing problem of bacterial and fungal resistance to antibiotics. This review focuses on the susceptibility of dermatophytic fungi, in particular Trichophyton rubrum, to PDT and shows its potential usefulness in treatment of clinical dermatophytoses. There are no data indicating significant differences in PDT susceptibility between various dermatophytes and it is unlikely that treatment problems of especially T. rubrum with current antimycotics would occur in case of PDT. Red light 5-aminolevulinic acid-mediated PDT is after repeated sessions successful in in vivo treatment of onychomycosis (fungal nail infection) caused by various dermatophytes. Regarding skin dermatophytoses, UVA-1 PDT with cationic porphyrins appears to be safe and efficient. Most effective toward T. rubrum ex vivo is 5,10,15-tris(4-methylpyridinium)-20-phenyl-[21H,23H]-porphine trichloride (Sylsens B) when combined with UVA-1 radiation or red light; this creates the possibility of efficiently treating nail infections and remaining spores in hair follicles. If the promising in vitro and ex vivo results could be transferred to clinical practice, then PDT has a good prospect to become a worthy alternative to established antifungal drugs.

The hunt for natural skin whitening agents

Skin whitening products are commercially available for cosmetic purposes in order to obtain a lighter skin appearance. They are also utilized for clinical treatment of pigmentary disorders such as melasma or postinflammatory hyperpigmentation. Whitening agents act at various levels of melanin production in the skin. Many of them are known as competitive inhibitors of tyrosinase, the key enzyme in melanogenesis. Others inhibit the maturation of this enzyme or the transport of pigment granules (melanosomes) from melanocytes to surrounding keratinocytes. In this review we present an overview of (natural) whitening products that may decrease skin pigmentation by their interference with the pigmentary processes.

Hydrophilic and lipophilic moisturizers have similar penetration profiles but different effects on SC water distribution in vivo

Dry skin is often treated with hydrophilic and/or lipophilic moisturizers. Hydrophilic moisturizers must penetrate the stratum corneum (SC) deeply to function properly, whereas lipophilic moisturizers should remain in the upper SC layers. In this study, both types of moisturizers were applied on volunteers for 3 h, after which the relative amount of moisturizer and the water distribution in the SC were determined using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy in combination with tape-stripping. The results show that while hydrophilic moisturizers penetrate much more readily than lipophilic moisturizers, the latter are abundantly present in the upper regions of the SC. It was also observed that a 3-h treatment with lipophilic moisturizer did not result in increased water levels in the SC, whereas hydrophilic moisturizers retained water where they are located. The results suggest that upon prolonged application, adequate amounts of moisturizer can be obtained in those regions where they may cause moisturization in the central part of the SC. However, a single application of 3 h is probably too short to exert increased hydration as measured with ATR-FTIR.

Preclinical studies with 5,10,15-Tris(4-methylpyridinium)-20-phenyl-[21H,23H]-porphine trichloride for the photodynamic treatment of superficial mycoses caused by Trichophyton rubrum

Dermatophytes are fungi that cause infections of keratinized tissues. We have recently demonstrated the susceptibility of the dermatophyte Trichophyton rubrum to photodynamic treatment (PDT) with 5,10,15-Tris(4-methylpyridinium)-20-phenyl-[21H,23H]-porphine trichloride (Sylsens B) in 5 mm citric acid/sodium citrate buffer (pH 5.2, formulation I). In this work, we examined the penetration of Sylsens B in healthy and with T. rubrum infected skin and we investigated the susceptibility of T. rubrum to PDT using formulation I and UVA-1 radiation (340-550 nm). Skin penetration studies were performed with formulations I and II (Sylsens B in PBS, pH 7.4) applied on dermatomed skin, human stratum corneum (SC), disrupted SC by T. rubrum growth and SC pretreated with a detergent. No penetration was observed in healthy skin. Disruption of SC by preceding fungal growth caused Sylsens B penetration at pH 7.4, but not at pH 5.2. However, chemically damaged SC allowed Sylsens B to penetrate also at pH 5.2. UVA-1 PDT was applied ex vivo during two fungal growth stages of two T. rubrum strains (CBS 304.60 and a clinical isolate). Both strains could be killed by UVA-1 alone (40 J/cm(2)). Combined with formulation I (1 and 10 microm Sylsens B for, respectively, CBS 304.60 and the clinical isolate), only 18 J/cm(2) UVA-1 was required for fungal kill. Therefore, PDT with 10 microm Sylsens B (formulation I) and 18 J/cm(2) UVA-1 could be considered as effective and safe. This offers the possibility to perform clinical studies in future.

Increased melanogenesis is a risk factor for oxidative DNA damage--study on cultured melanocytes and atypical nevus cells

Melanin synthesis is an oxygen-dependent process that acts as a potential source of reactive oxygen species (ROS) inside pigment-forming cells. The synthesis of the lighter variant of melanin, pheomelanin, consumes cysteine and this may limit the capacity of the cellular antioxidative defense. We show that tyrosine-induced melanogenesis in cultured normal human melanocytes (NHM) is accompanied by increased production of ROS and decreased concentration of intracellular glutathione. Clinical atypical (dysplastic) nevi (DN) regularly contain more melanin than do normal melanocytes (MC). We also show that in these cultured DN cells three out of four exhibit elevated synthesis of pheomelanin and this is accompanied by their early senescence. By using various redox-sensitive molecular probes, we demonstrate that cultured DN cells produce significantly more ROS than do normal MC from the same donor. Our experiments employing single-cell gel electrophoresis (comet assay) usually reveal higher fragmentation of DNA in DN cells than in normal MC. Even if in some cases the normal alkaline comet assay shows no differences in DNA fragmentation between DN cells and normal MC, the use of the comet assay with formamidopyrimidine DNA glycosylase can disclose that the DNA of the cultured DN cells harbor more oxidative damage than the DNA of normal MC from the same person.

Investigation of conditions involved in the susceptibility of the dermatophyte Trichophyton rubrum to photodynamic treatment

BACKGROUND

Photodynamic treatment (PDT) refers to a treatment with light-activated agents (photosensitizers) in combination with visible light and molecular oxygen. Recently, we have demonstrated that the porphyrins, 5,10,15-tris(4-methylpyridinium)-20-phenyl-[21H,23H]-porphine trichloride (Sylsens B) and deuteroporphyrin monomethylester (DP mme) are excellent photosensitizers to be used against Trichophyton rubrum both in vitro and ex vivo.

OBJECTIVES AND METHODS

The objective of this study was to investigate the key factors involved in PDT efficacy of both photosensitizers in an ex vivo situation during different fungal growth stages using a recently developed ex vivo model. The study focused on the influence of pH and ion strength of incubation media, photochemical properties of the photosensitizers (spectra and singlet oxygen production), and the effect of several scavengers of reactive oxygen species (sodium azide, histidine, mannitol) and phenylmethylsulphonylfluoride (keratinase inhibitor) on the PDT efficacy.

RESULTS AND CONCLUSIONS

The results show that an optimal pH and low concentrations of calcium are crucial for a selective binding of Sylsens B to the fungus, leading to an increased PDT efficacy. This selective binding to T. rubrum cannot be accomplished for DP mme. It can be concluded that the prerequisite for successful treatment is a use of a low molarity solution of pH 5, supplemented with a chelating agent and a keratinase activity-repressing agent. Under these conditions, PDT with Sylsens B inactivates, initially via singlet oxygen, effectively the fungus in different fungal growth stages.

Susceptibility to UV-A and UV-B Provocation Does Not Correlate With Disease Severity of Polymorphic Light Eruption

OBJECTIVE

To examine whether the ease of disease provocation by UV-A and/or UV-B radiation correlates with clinical features of polymorphic light eruption (PLE), including those indicative of disease severity.

DESIGN

Intervention study.

PATIENTS

One hundred forty-three patients with PLE.

INTERVENTIONS

Provocation testing with broadband UV-A and UV-B lamps. Additionally, a range of clinical characteristics of the disorder, including a 5-item PLE severity score, was assessed by questionnaire.

MAIN OUTCOME MEASURES

Percentage of PLE rash induction by UV-A and UV-B provocation, differences between the skin types, and correlation between the results of provocation and a range of clinical characteristics of the disorder, including a 5-item PLE severity score.

RESULTS

Rash provocation was seen in 78.3% of patients after UV-A and in 46.7% after UV-B exposure. Neither UV-A nor UV-B provocation showed a significant association with the total 5-item severity score. The UV-B reactivity was associated with a high score on the severity item "number of months affected per year" (P = .04), whereas UV-A responsiveness showed a tendency for association with facial involvement (P = .06).

CONCLUSION

The objective assessment of UV-A or UV-B susceptibility in this large group of patients showed no significant relationship with clinical disease severity.

Papillary thyroid carcinoma in a patient with sarcoidosis treated with minocycline

Long-term treatment with minocycline is occasionally associated with the development of black thyroid syndrome in which thyroid cancer is frequently found. Here, we report a patient with cutaneous, pulmonary and thyroid sarcoidosis who developed papillary thyroid carcinoma in the presence of a black thyroid syndrome after being treated with minocycline for 2.5 years.

Acitretin induces capillary leak syndrome in a patient with pustular psoriasis

Capillary leak syndrome is a rare and potentially life-threatening condition caused by a shift of intravascular fluid and proteins to the interstitial space. We describe a patient with pustular psoriasis in whom capillary leak syndrome developed after the start of acitretin. Immediate withdrawal of retinoic acid is necessary and corticosteroid therapy should be considered.

A novel ex vivo skin model to study the susceptibility of the dermatophyte Trichophyton rubrum to photodynamic treatment in different growth phases

BACKGROUND

Dermatophytes are fungi that can cause infections of skin, hair and nails because of their ability to feed on keratin. Superficial mycoses are among the most prevalent infectious diseases worldwide. Two important restrictions of current therapeutic options are the recurrence of the infection and prolonged treatment. This is especially true for infections caused by Trichophyton rubrum, a widely distributed dermatophyte. The application of photosensitizers for treatment of fungal infections is, within the field of photodynamic treatment (PDT), relatively new. Recently, we demonstrated that the porphyrins 5,10,15-tris(4-methylpyridinium)-20-phenyl-[21H,23H]-porphine trichloride (Sylsens B) and deuteroporphyrin monomethylester (DP mme) were excellent photosensitizers towards T. rubrum when using red light.

OBJECTIVES AND METHODS

To evaluate the photodynamic effectiveness of the porphyrins in a situation that mimics the clinical situation, we developed an ex vivo model using human stratum corneum. This model offers the possibility of applying PDT at different time points during the germination and subsequent development of T. rubrum microconidia. The model was used for two different incubation media, Dulbecco's modified Eagle medium (DMEM) and distilled water.

RESULTS AND CONCLUSIONS

We demonstrated that the PDT susceptibility of T. rubrum depended on the time of PDT application after spore inoculation. A decrease in susceptibility was observed with increasing time of PDT application for both photosensitizers in DMEM. Changing the incubation medium to distilled water resulted in an increased fungicidal effect for Sylsens B and in a decreased effect for DP mme. We conclude that T. rubrum is susceptible to PDT in a situation that mimics the clinical situation. The fungicidal effect of PDT on fungal spores is of particular importance.

Ultraviolet-A (UVA-1) radiation suppresses immunoglobulin production of activated B lymphocytes in vitro

Previous studies have shown that low-dose ultraviolet-A (UVA-1) total body irradiations were capable of improving disease activity in patients with systemic lupus erythematosus (SLE). We hypothesized that UVA-1-induced suppression of immunoglobulin production by activated B cells in the dermal capillaries could be (partly) responsible for this effect. Our experiments with donor skin demonstrated that approximately 40% of UVA-1 could penetrate through the epidermis. Irradiation of peripheral blood mononuclear cells (PBMCs) with 2 J/cm(2) of UVA-1 resulted in 20% cell death. This toxic effect could be prevented totally by preincubation of the cell cultures with catalase. This indicates that the generation of hydrogen peroxide plays a role in UVA-1 cytotoxicity. T cells and B cells appeared to be less susceptible to UVA-1 cytotoxicity than monocytes. With the use of a CD40-CD40L B cell activation method we measured immunoglobulin production after various doses of UVA-1 irradiation (0-2 J/cm(2)). The doses of 2 J/cm(2) caused a significant decrease of IgM, IgG, IgA and IgE production under the conditions of interleukin (IL)-10 or IL-4 (IgE) stimulation. Although UVA-1 can cause apoptosis of B lymphocytes, we show that relatively low doses of UVA-1 radiation also affect the function of these cells. Both effects may be responsible for the observed improvement of disease activity in SLE patients.

Topical photodynamic therapy for prevention of new skin lesions in renal transplant recipients

Preclinical data suggest that topical methyl aminolevulinate photodynamic therapy may have potential in preventing new skin lesions in transplant recipients. An open intra-patient randomized study investigated the prevention potential of this treatment in 27 renal transplant patients with actinic keratoses and other skin lesions in two circular contralateral areas (5 cm diameter). The treatment area surface was debrided and methyl aminolevulinate cream (160 mg/g) was applied for 3 h prior to illumination by non-coherent red light (570-670 nm, light dose 75 J/cm2). The control area was not treated. The mean time to occurrence of the first new lesion was significantly longer in treated than control areas (9.6 vs 6.8 months, treatment difference 2.9 [95% confidence interval 0.2 to 5.5] months, p = 0.034). Over 12 months, 62% (16/26) of treated areas were free from new lesions compared with 35% (9/26) in control areas. These findings indicate that topical methyl aminolevulinate photodynamic therapy is a promising preventive treatment against new skin lesions in immunosuppressed patients.

Mechanistic studies of melanogenesis: the influence of N-substitution on dopamine quinone cyclization

The influence of side-chain structure on the mode of reaction of ortho-quinone amines has been investigated with a view, ultimately, to developing potential methods of therapeutic intervention by manipulating the early stages of melanogenesis. Four N-substituted dopamine derivatives have been prepared and quinone formation studied using pulse radiolysis and tyrosinase-oximetry. Ortho-quinones with an amide or urea side chain were relatively stable, although evidence for slow formation of isomeric para-quinomethanes was observed. A thiourea derivative cyclized fairly rapidly (k = 1.7/s) to a product containing a seven-membered ring, whereas a related amidine gave more rapidly (k approximately 2.5 x 10(2)/s) a stable spirocyclic product. The results suggest that cyclization of amides, ureas and carbamates (NHCO-X; X = R, NHR or OR) does not occur and is not, therefore, a viable approach to the formation of tyrosinase-activated antimelanoma prodrugs. It is also concluded that for N-acetyldopamine spontaneous ortho-quinone to para-quinomethane isomerization is slow.

Normalized ultraviolet (UV) induction of Langerhans cell depletion and neutrophil infiltrates after artificial UVB hardening of patients with polymorphic light eruption

BACKGROUND

Ultraviolet (UV) B hardening has been widely used as a prophylactic treatment in patients with polymorphic light eruption (PLE). Recent investigations have shown that in patients with PLE Langerhans cells (LCs) and neutrophils display less migration from and to the epidermis after an intense UVB irradiation compared with controls.

OBJECTIVES

To investigate the effect of UVB hardening of patients with PLE on their cell migratory responses after intense UVB exposure.

METHODS

Thirteen patients with PLE were recruited and UVB provocation testing was performed before entering the study. Among these patients, seven developed PLE rash upon UVB provocation ('UVB-P') and the other six did not respond ('UVB-NP'). Eleven age/sex-matched controls were included. Buttock skin of all included individuals was exposed to 6 minimal erythema doses (MED) of UVB (TL-12 lamps). Biopsies were taken after 24 h and 48 h, together with one control biopsy of unirradiated skin. Patients received total-body UVB hardening therapy consisting of 12 irradiations, on average rising from 10% to 140% of the initial MED in 6 weeks. Subsequently, MEDs were reassessed and biopsies were taken from newly irradiated (6 MED UVB) and unirradiated buttock skin. Skin sections were stained for the presence of LCs, macrophages and neutrophils. The cross-sectional area (in percentage) of positively stained cells within the epidermis was assessed from patients before and after hardening and compared with controls.

RESULTS

Before therapy, epidermal LC depletion and neutrophil influx at 48 h after 6 MED were most significantly reduced in 'UVB-P' patients (P = 0.025 and P =0.006, respectively) when compared with controls. 'UVB-NP' patients did not differ significantly from controls. After therapy, there were no longer any significant differences in the cell numbers among these three groups.

CONCLUSIONS

UVB hardening significantly improves UV-induced cell migratory responses in patients with PLE. UVB provokability of PLE appears to be most strongly linked to reduced UVB-induced trafficking of LCs and neutrophils, and 'UVB-P' patients show normalization of these responses after UVB hardening.

Cutaneous side-effects of transdermal iontophoresis with and without surfactant pretreatment: a single-blinded, randomized controlled trial

BACKGROUND

Iontophoresis, a method that facilitates drug transport across skin by an external electrical field, offers the possibility for long-term transdermal delivery of compounds in a well-controlled manner. In general, the literature supports the contention that iontophoresis is a safe procedure. However, there are important medical issues concerning the epidermal and dermal effects of iontophoresis that have not been extensively investigated. Specific and strictly controlled studies on the dermal effect of iontophoresis are scarce.

OBJECTIVES

The aim of this study was to investigate the cutaneous side-effects of transdermal iontophoresis application in healthy human volunteers.

METHODS

This was a single-blinded, randomized and parallel design study. In one group (n=12) subjects were treated nonocclusively with a surfactant formulation followed by iontophoresis (3-h application at a current density of 250 microA cm(-2)). In another group (n=12) iontophoresis alone was performed. No drug was included in these studies. The corresponding passive treatments served as controls. Noninvasive methods including sensation record, transepidermal water loss (TEWL), skin colour and the visual scoring were used to assess cutaneous effects.

RESULTS

Tingling and itching were commonly experienced in the first 30 min of the current application. Iontophoresis in combination with the pretreatment induced significant increases in TEWL values and in skin redness, and resulted in slight to mild erythema and oedema compared with the control. Compared with the iontophoresis alone, the presence of surfactant pretreatment caused slightly more skin irritation (erythema and oedema) but did not further disturb the skin barrier function.

CONCLUSIONS

The transdermal iontophoresis challenges the skin barrier function and induces transient mild skin irritation, but does not cause any permanent damage to the skin when applied for 3 h at a current density of 0.25 mA cm(-2).

UVA-1 cold light therapy in the treatment of atopic dermatitis: 61 patients treated in the Leiden University Medical Center

BACKGROUND

UVA-1 has been shown to be effective in the treatment of patients with atopic dermatitis. However, its optimal therapeutic conditions are not yet fully established.

METHODS

In an open prospective study we retrospectively compared the effect of 4 weeks therapy (32 patients) with the effect of the usual 3 weeks therapy (29 patients) in patients with atopic dermatitis, using a medium dose UVA-1 cold light (45 J/cm2), 5 days a week.

RESULTS

Scoring atopic dermatitis index (SCORAD) and dermatology life quality index (DLQI) quality of life indexes improved significantly during both 3 and 4 weeks UVA-1. Patients who were treated for 4 weeks showed a superior improvement of the SCORAD index [23.12 points, 95% confidence interval (CI) 16.09-30.16, vs. 13.32 points, 95% CI 5.61-21.04, P = 0.059], and the DLQI (5.41 points, 95% CI 2.38-7.88, vs. 3.86 points, 95% CI 1.88-5.84, P = 0.360), compared with patients who were treated for 3 weeks. However, the differences did not reach statistical significance. Only patients who were treated for 4 weeks were able to maintain their improvement 6 weeks after therapy. In both groups 50% of patients had intermittently used mild topical corticosteroids in the follow-up period.

CONCLUSION

Extension of UVA-1 therapy from 3 to 4 weeks results in a clinically relevant improvement of the outcome, and more prolonged therapeutic effects, measured by the SCORAD index.

UVB-induced leucocyte trafficking in the epidermis of photosensitive lupus erythematosus patients: Normal depletion of Langerhans cells

BACKGROUND

The pathogenic mechanisms of UV-induced skin lesions of lupus erythematosus (LE) are unknown. In a recent study of pathogenic mechanisms of polymorphic light eruption (PLE), significantly more Langerhans cells (LCs) persisted in the epidermis after UVB overexposure than in healthy individuals. Interestingly, the same phenomenon was observed in one subacute cutaneous lupus erythematosus (SCLE) patient. It could therefore be hypothesized that both photodermatoses share a common pathogenic mechanism of photosensitivity. In the present study, we tested this hypothesis by investigating leucocyte trafficking in the initial phase of cutaneous LE after intense UVB exposure.

METHODS

In 22 photosensitive LE patients (12 chronic discoid lupus erythematosus, seven systemic lupus erythematosus and three SCLE) and nine age/sex-matched controls, uninvolved buttock skin was exposed to six minimal erythemal dose (MED) UVB radiation. Subsequently, biopsies were taken after 24, 48 and 72 h, and one control biopsy was taken from unirradiated skin. Skin sections were stained for the presence of LCs, neutrophils and macrophages. Areal percentages of positively stained cells within the epidermis were quantified and compared between the patients and controls.

RESULTS

A gradual decrease of epidermal LCs and a gradual increase of epidermal neutrophils and macrophages at several timepoints after six MED irradiation was observed equally in both LE patients and controls.

CONCLUSION

Immunohistopathology of irradiated uninvolved skin of photosensitive LE patients did not reveal the same pathologic trafficking of LCs and neutrophils as described for PLE patients. We conclude that different mechanisms are operative in the pathogenesis of PLE and photosensitive LE.

[Risk factors for skin melanoma: genetic factors probably more important than exposure to sunlight]

Pigmented naevi (moles) are increasingly regarded as risk factors for the development of melanoma. The probability of melanoma developing from congenital naevi is proportional to the volume of the naevi. The risk of melanoma development from large naevi (diameter > 20 cm) is already present in the early years of childhood. The most important risk factor is the higher number of acquired naevi. This applies particularly to dysplastic (also called clinically atypical) naevi that not only represent the highest risk group but are also considered potential melanoma precursors. The development of acquired naevi (including dysplastic naevi) is dependant on the degree of skin pigmentation. The role of sunlight (ultraviolet radiation) in the development of melanoma is less significant than is generally assumed. The indirect effect of sunlight on melanoma development is to stimulate naevogenesis. One of the risk-modifying genes is the gene coding for melanocortin-1-receptor (MC1R). The presence of some gene variants has been found to lead to changes in melanin synthesis and is associated with a higher risk of melanoma. Recent research has shown that dysplastic naevi synthesise more phaeomelanin. There are also strong indications that dysplastic naevus cells suffer from chronic oxidative stress. This situation can lead to hypermutability and genetical instability.

The Combined Effects of Extracts Containing Carotenoids and Vitamins E and C on Growth and Pigmentation of Cultured Human Melanocytes

In the present study, we investigated the effects of tomato extract (TE) containing lycopene and palm fruit extract (PE) rich in carotenoids on the growth and pigmentation of melanocyte cultures of Caucasian origin. The extracts were tested at different concentrations and in combination with vitamins E and C. Melanocytes with basic and increased (tyrosine-induced) pigmentation were treated in short-term and long-term experiments. Prevention of UVA-induced DNA damage was studied by using the comet assay. Melanocytes with stimulated melanin production showed reduced growth. Incubation of the cells with TE/PE (20/4 microg/ml) in combination with 35 microM vitamin E and 100 microM vitamin C (COMB 20/4) reduced this growth inhibition, especially in the long-term cultures. Increased production of melanin pigment was obtained when the cells were treated with 2.5 x and 10 x higher concentrations of the TE/PE and the same concentration of vitamins E and C (COMB 50/10 and 200/40). Reduced DNA damage was found after UVA irradiation in cells preincubated with COMB 50/10. The results indicate that the presence of carotenoids from TE and PE in combination with vitamins E and C may influence growth and pigmentation in melanocyte monocultures. Depending on the concentration of the carotenoid mixtures, their presence may provide some protection against the melanogenic intermediates and/or exogenous DNA damage.

Efficacy of UVA-1 cold light as an adjuvant therapy for systemic lupus erythematosus

OBJECTIVE

The assessment of the efficacy of therapy of patients with moderately active systemic lupus erythematosus (SLE) with low doses of UVA-1 cold light.

METHODS

A double blind, placebo-controlled, cross-over study design was used for the examination of the efficacy of low doses of UVA-1 radiation (12 J/cm2/day for 15 days) in 12 patients.

RESULTS

UVA-1 treatment resulted in a significant decrease of well-validated disease activity indexes [the SLE Activity Measure (SLAM) (P < 0.001) and the SLE Disease Activity Index (SLEDAI) (P = 0.007)], whereas neither score improved significantly during placebo treatment. Furthermore, UVA-1 therapy proved to be more effective [mean decrease 4.8 points) than placebo (mean decrease -1.7 points (i.e. an increase)] when measured by the SLAM (P = 0.001, 95% CI -7.56 to -2.28), but not by the SLEDAI. Two patients had transient skin reactions at the beginning of treatment.

CONCLUSION

UVA-1 therapy appears to be a useful adjuvant treatment modality for patients suffering from moderately active SLE. Its effect could possibly be explained by reduction of B-cell function or apoptosis of plasma cells.

Tyrosine-induced melanogenesis shows differences in morphologic and melanogenic preferences of melanosomes from light and dark skin types

The quality, quantity and distribution of melanosomes in epidermis play a crucial role in the determination of skin color and its sensitivity to UV radiation. Melanocyte cultures originating from individuals with light and dark skin types were grown in media with varying concentration of L-tyrosine. Melanosomal melanin content and the size of the organelles were measured after subcellular fractionation. In light-skin type cells, increased melanin production resulted in a more elliptical shape of melanosomes. In melanosomes that constitutively produce more melanin, the tyrosine-induced melanogenesis caused enlargement in all dimensions. X-ray microanalysis provided evidence that the increase in sulfur content induced by high tyrosine concentration was more prominent in the melanosomes from light skin types. A ratio between pheomelanin and eumelanin found in light-skin type melanosomes by HPLC was increased more markedly than that in melanosomes from dark skin melanocytes. These findings suggest that the melanocytes of light-skinned individuals exhibit a preference for pheomelanogenesis. Pheomelanin production is a thiol-consuming process and that might increase the risk of oxidation stress in these cells. This fact, together with the limited ability of pheomelanin to absorb UV radiation may lead to an elevated skin cancer risk among light-skinned individuals.

Disturbed melanin synthesis and chronic oxidative stress in dysplastic naevi

Dysplastic naevi (DN) are a known risk factor for malignant melanoma. Their occurrence is closely connected with the degree of skin pigmentation. People with a light complexion are more likely to develop DN than dark-skinned individuals. We examined the proposition that DN exhibit altered melanin formation, which may be involved in their malignant transformation. X-ray microanalysis was used to study the composition of melanosomes from DN and to compare the results with those obtained from melanomas, banal (dermal) naevi and normal cutaneous melanocytes. We analysed sulphur (an indicator of phaeomelanin) and two metals, iron and calcium, involved in oxidative stress. FACS analysis of dihydrorhodamine-123-labelled cells was employed to quantify differences in the production of radical oxygen species in DN cells and normal skin melanocytes. A significantly higher sulphur content was found in melanosomes from DN cells and melanoma cells when compared with normal melanocytes and naevus cells from banal naevi. In addition, melanosomes of DN cells and melanoma cells contained higher amounts of iron and calcium. In the case of calcium, this was associated with a significantly elevated cytoplasmic concentration. FACS analysis showed that DN cells exhibited higher concentrations of radical oxygen species than normal skin melanocytes from the same individuals. We propose that increased phaeomelanogenesis in DN cells is connected with oxidative imbalance, which is reflected by increased intracellular concentrations of reactive oxygen species and raised calcium and iron concentrations. We show that the metabolic alterations in DN cells resemble those found in melanoma cells. Our findings provide support for the idea that DN cells are true precursor lesions of melanoma.

A double-blind placebo-controlled trial of UVA-1 in the treatment of dyshidrotic eczema

We carried out a randomized, double-blind, placebo-controlled study to examine the therapeutic effect of UVA-1 irradiation on dyshidrotic hand eczema. Twenty-eight patients were randomised to receive UVA-1 irradiation (40 J/cm2) or placebo, five times a week for 3 weeks. Evaluated by the DASI and the VAS, UVA-1 was significantly more effective after 2 and 3 weeks. Also, desquamation and area of affected skin improved significantly more after UVA-1. We did not find any difference regarding the response of patients with increased IgE blood levels (>100 IU/mL) compared with those having normal IgE levels. No side effects were observed. This study indicates that UVA-1 can cause a significant improvement of both objective and subjective signs of dyshidrotic eczema.

Homozygous germline mutation of CDKN2A/p16 and glucose-6-phosphate dehydrogenase deficiency in a multiple melanoma case

CDKN2A is regarded as a major melanoma susceptibility gene. A 19 bp deletion has been detected within Dutch families with familial atypical multiple mole-melanoma syndrome. Genetic analysis revealed two individuals with germline deletions in both copies of CDKN2A. One of them did not develop atypical naevi or melanoma, but died of adenocarcinoma at the age of 54 years. This report describes the results of the investigation of the second p16-null individual, who was also found to have glucose-6-phosphate dehydrogenase (G-6-PD) deficiency and who has developed many atypical naevi and seven melanomas. Using electron microscopic techniques, striking alterations in melanosomal structures and deviations in their sulphur, iron and calcium composition indicating a strong preference for phaeomelanogenesis and increased oxidative stress were found in the naevus cells of the patient. Using an in vitro model, we demonstrated that leaking melanin precursors may strongly enhance oxidative DNA damage through iron release from ferritin. We conclude that the homozygous p16 deletion is not sufficient for the development of a dysplastic naevus phenotype and melanoma. However, when an additional modifying factor, such as G-6-PD deficiency, increases the level of oxidative DNA damage in melanin-producing cells, the risk of developing atypical naevi and their malignant transformation may increase significantly.

Keratinocytes control the pheo/eumelanin ratio in cultured normal human melanocytes

The pheo/eumelanin ratio of cultured normal human melanocytes is distinct from the ratio observed for the same cells in vivo where they are in close contact with keratinocytes. To study the possible involvement of keratinocytes in the control of melanogenesis, we compared quantitatively and qualitatively the melanin production in melanocyte mono-cultures, in melanocyte-keratinocyte co-cultures and in pigmented reconstructed epidermis. Pheomelanin and eumelanin contents were assessed by high-performance liquid chromatography with electrochemical and fluorometric detection of their specific degradation products and revealed striking differences in the presence of keratinocytes. In the absence of keratinocytes (melanocyte mono-cultures), we observed a very limited eumelanin production and a very high pheomelanin synthesis. The pheo/eumelanin ratio in mono-cultures could be slightly influenced by changing the composition of the culture medium, however, the very strong imbalance in favor of pheomelanin remained unchanged. An induction of eumelanin synthesis accompanied by an important reduction of pheomelanin formation was only observed in the presence of keratinocytes. The pheo/eumelanin ratio in melanocyte mono-culture dropped from 1043 down to about 25 in the presence of keratinocytes (co-cultures). The same observations were made when the melanocytes were integrated into a reconstructed human epidermis. Interestingly, under co-culture conditions resulting in only a partial contact between melanocytes and keratinocytes, the reduction of the pheo/eumelanin ratio were less pronounced. From these results we conclude that keratinocytes play an important role in the melanin production, affecting the melanogenic pathways.