Skin Barrier Function and Its Relationship With IL-17, IL-33, and Filaggrin in Malar Melasma.

BACKGROUND: The pathogenesis of melasma remains unclear. Interleukin (IL)-17, a proinflammatory mediator, disturbs barrier function. Filaggrin (FLG) is a protein involved in epidermal barrier homeostasis and may be affected by IL-17 and IL-33. OBJECTIVE: To evaluate epidermal barrier function in malar melasma and its association with the expression of FLG, IL-17, and IL-33. METHODS: Twenty patients with malar melasma were included in this study. Colorimetric and transepidermal water loss (TEWL) was measured in lesional and adjacent unaffected skin at baseline and 30 minutes after barrier disruption using the tape-stripping test. Biopsies from melasma and perilesional skin were performed to evaluate the presence of FLG by immunohistochemistry, and profilaggrin, IL-17, and IL-33 expression were analyzed by reverse transcription-qualitative polymerase chain reaction. RESULTS: After the stripping test, the erythema and TEWL values were higher in the melasma than in the unaffected skin ( P = 0.01). Thirty minutes later, TEWL diminished, but it remained higher than in the perilesional skin. Profilaggrin increased as TEWL gradually decreased (R = -0.68, P = 0.04). FLG and IL-17 were higher in the melasma than in the perilesional skin ( P = 0.003). IL-17 and profilaggrin expression were positively associated (R = 0.60, P = 0.04). IL-33 expression was higher in the adjacent normal skin than in the melasma ( P = 0.01). CONCLUSION: This study found subclinical inflammation in the skin adjacent to the melasma, dysfunction of the epidermal barrier in lesions associated with chronic inflammation, and an abnormal differentiation process promoting an increase in FLG. These findings highlight the need to preserve the integrity of the facial stratum corneum in these patients.

Nutritional deficiency dermatitis related to branched-chain amino acid restriction in a child with maple syrup urine disease.

We present a one-year-old girl with maple syrup urine disease with dermatitis secondary to the restriction of amino acids as part of the treatment. We present the clinical evolution and histopathological correlation.

Analysis of cutaneous pigmentation in a sample / Análisis de la pigmentación cutánea en una muestra.

Background: The blend of hemoglobin, carotenes, and melanin defines the skin color. Constitutive pigmentation is genetically determined, facultative color is induced when skin is exposed to environment. The objective was to quantify both pigmentations in a sample of Mexican population and to analyze its relationship with sex, age, and phototype. Methods: We evaluated 259 individuals during the winter. Skin colorimetry was obtained by diffuse reflectance spectrometry, using the International Commission of Illumination coordenates. L*a*b* parameters were measured and the individual typological angle (ITA) was estimated from forehead, thorax, neck, forearms, and buttocks areas. Results: Facultative pigmentation differed from constitutive in L*, a*, and ITA° values. In men, L* and ITA° parameters were lower. Constitutive pigmentation was similar between sexes. Phototypes III, IV, and V showed differences in L*, b*, and ITA°. Facultative values such as L*, a*, ATI°, and the constitutive a* reduce as age increases. Conclusions: The cutaneous tones of a sample of population were quantified recognizing their values for white, light brown, and dark brown skin. A reference frame for research related to cutaneous pigmentation in Mexico is presented.

Antecedentes: La mezcla de melanina, hemoglobina y carotenos definen el color cutáneo. La pigmentación constitutiva está determinada genéticamente, la facultativa se induce cuando la piel se expone al ambiente. El objetivo fue cuantificar ambas pigmentaciones en una muestra de población mexicana, y analizar su relación con el género, edad y fototipo. Métodos: Se evaluaron 259 personas durante un periodo invernal. La colorimetría cutánea se obtuvo mediante espectrometría de reflectancia difusa utilizando las coordenadas de la Comisión Internacional de Iluminación. Se registraron los valores L*a*b* y se estimó el ángulo tipológico individual (ATI°) en frente, tórax, cuello, antebrazos y glúteos. Resultados: La pigmentación facultativa difirió de la constitutiva en los parámetros L*, a*, y ATIº. En hombres, los valores facultativos de L* y ATI° fueron menores. La pigmentación constitutiva fue similar entre sexos. Los fototipos III, IV y V muestran diferencias en L*, b* y ATI°. Los valores facultativos L*, a*, ATI° y el constitutivo a* se reducen al incrementarse la edad. Conclusiones: Se cuantificaron los tonos cutáneos de una muestra de población reconociéndose los valores para la piel blanca, morena clara y morena oscura. Se presenta un marco de referencia para estudios relacionados con la pigmentación cutánea en México.

Repigmentation patterns induced by NB-UVB and their relationship with melanocytic migration and proliferation in vitiligo.

BACKGROUND/PURPOSE: Vitiligo is the most commonly acquired depigmentation disorder of the skin and is characterized by the destruction of melanocytes. Ultraviolet phototherapy with narrow band (UVB-NB) induces proliferation, differentiation, maturation, and migration of melanocytes. The clinical repigmentation is featured by follicular, marginal, and diffuse patterns. The aim of this study was to observe the process involved in the melanocyte migration and proliferation among these patterns and the unresponsive lesions following UVB-NB phototherapy. The focal adhesion kinase (FAK) and c-KIT were used as markers of melanocyte migration and differentiation, respectively. METHODS: A total of 17 vitiligo patients under UVB-NB therapy were selected. The patients expressed the three repigmentation patterns as well as unresponsive lesions at the conclusion of a 30-session cycle. Skin biopsies were evaluated by immunohistochemistry and qRT-PCR. RESULTS: We found an increased expression of c-KIT in the follicular pattern compared to the diffuse pattern that was expressed predominantly of FAK. Marginal pattern expressed both proteins. The unresponsive achromic lesions showed poor expressions of both markers. CONCLUSION: Proliferation was prominent in the follicular pattern, but migration was prominent in the diffuse pattern. For the marginal pattern, both dynamics were present. The absence of these markers in vitiligo lesions suggests a lack of response to UVB-NB.

CD4, IL-17, and COX-2 Are Associated With Subclinical Inflammation in Malar Melasma.

The pathogenesis of melasma, a common, photo-induced hyperpigmentary disorder, is not clearly understood. Significant factors linked to melasma are ultraviolet radiation exposure and genetic predisposition. Histological analysis has demonstrated that melasma is caused by a network of cellular interactions among melanocytes, keratinocytes, mast cells, fibroblasts, and dermal vasculature exhibits, features similar to chronic sun damage. Dermal inflammation caused by ultraviolet radiation might play an important role in the hyperpigmentation and reactivation of melasma lesions through the production of melanogenic cytokines and growth factors. Because the role of inflammation in this disorder is unknown, we used histochemistry, immunohistochemistry, and quantitative real-time polymerase chain reaction to evaluate melasma lesions from healthy female patients (n = 20) with malar melasma. Lesional skin without specific solar exposure or photoprotection measures within the previous 4 weeks was compared with nonlesional skin. The increased lymphocytic infiltrate in lesional skin was mainly composed of CD4 T cells, mast cells, and macrophages. Levels of the cytokine interleukin (IL)-17 and the proinflammatory mediator cyclooxygenase (COX)-2 were significantly elevated in affected skin compared with healthy skin. In addition, the Melasma Activity and Severity Index score, fraction of solar elastosis, and epidermal melanin were positively associated with COX-2 expression. There was no statistically significant difference in IL-1α, IL-1ß, R-IL1, IL-6, IL-8, vascular endothelial growth factor, and tumor necrosis factor alpha expression levels. Together, these data indicated that melasma under unchallenged conditions is characterized by chronic inflammatory cells and mediators, which may explain its recurrent nature.

Hailey-Hailey disease improved by fractional CO2 laser.

Hailey-Hailey disease (HHD), also known as benign familial pemphigus, is an autosomal dominant skin condition that affects the adhesion of epidermal keratinocytes. Although the initial manifestation of flaccid vesicles on erythematous or normal skin in flexure sites frequently goes unnoticed, large, macerated, exudative plaques of superficial erosions with crusting are observed at the time of diagnosis. There is no specific treatment for HHD, and most cases are symptomatically supported. However, infrared laser ablation has been somewhat helpful. We present a case successfully treated with fractional CO2 laser showing a long-term favourable outcome and no adverse effects. Thus, this modality could be an alternative to full ablation for this condition.

Hyperpigmentation and atrophy in folds as cutaneous manifestation in a case of mitochondrial myopathy.

Mitochondrial myopathies are inborn metabolism defect diseases manifested by symptoms reflecting failure of the final step in the mitochondrial respiratory chain. Clinical expression of these conditions can vary widely, but typically includes organ systems with a high energy demand, such as striated muscle, myocardium, and nervous and liver tissues. In contrast, cutaneous manifestations are rare and are non-specific, most commonly presenting as pigmentation disorders. In this case report, we present a case of Alpers syndrome accompanied by hyperpigmentation and atrophy in skin folds.

Near-visible light and UV photoprotection in the treatment of melasma: a double-blind randomized trial.

BACKGROUND: Melasma is an acquired hyperpigmentation on sun-exposed areas. Multiple approaches are used to treat it, but all include broad ultraviolet (UV)-spectrum sunscreens. Visible light (VL) can induce pigmentary changes similar to those caused by UV radiation on darker-skinned patients. OBJECTIVE: To assess the efficacy of sunscreen with broad-spectrum UV protection that contains iron oxide as a VL-absorbing pigment (UV-VL) compared with a regular UV-only broad-spectrum sunscreen for melasma patients exposed to intense solar conditions. METHODS: Sixty-eight patients with melasma were randomized in two groups to receive either UV-VL sunscreen or UV-only sunscreen, both with sun protection factor ≥ 50, over 8 weeks. All patients received 4% hydroquinone as a depigmenting treatment. At onset and at conclusion of the study, they were assessed by the Melasma Activity and Severity Index (MASI; a subjective scale), colorimetry (L*) and histological analysis of melanin. RESULTS: Sixty-one patients concluded the study. At 8 weeks, the UV-VL group showed 15%, 28% and 4% greater improvements than the UV-only group in MASI scores, colorimetric values and melanin assessments, respectively. CONCLUSIONS: UV-VL sunscreen enhances the depigmenting efficacy of hydroquinone compared with UV-only sunscreen in treatment of melasma. These findings suggest a role for VL in melasma pathogenesis.

In vitro assessment of commercial sunscreens available in Latin America.

In Latin America, people have largely abandoned the practice of wearing hats and traditional clothing that provided skin protection. Sunscreen application has therefore become essential to protect against the increased sun exposure. The physician-prescribed medical-grade sunscreens provide sufficient sun protection but the requirement for regular use puts a financial burden on the patient that is often not sustainable. An appropriate sunscreen should provide a high and broad ultraviolet (UV) protection against UVB and UVA. Several over-the-counter (OTC) sunscreens have been developed for sale at affordable prices and are available for purchase in convenient locations, such as local grocery stores. The aim of this study was to assess the in vitro UV protection of 34 popular OTC sunscreens found in the Latin American market. UV absorbance/transmittance was quantified by diffusion transmission spectroscopy using coarse silica plaques. Photostability was tested by irradiating them with simulated solar light and calculating the sun protection factor (SPF), critical length of absorption (C lambda ), UVA/UVB ratio, and the spectral uniformity index (SUI). The results indicated that the in vitro SPFs were significantly lower than the value declared on the labels, particularly for those claiming high SPF values; however, the majority of these sunscreens offered high levels of UV protection. Considering the advantages of low cost and ample accessibility, we concluded that this sample of OTC sunscreens can be beneficial to the general public by providing some level of skin protection from solar radiation, and may be promoted to improve compliance with recommended photoprotection behavior.

Cutaneous congenital candidiasis in a full-term newborn from an asymptomatic mother.

A male infant of 2,900 g was born at term to a 19-year-old primigravida woman who had adequate prenatal care and no major complications detected during the pregnancy. The only reported medical event was an episode of urinary tract infection by E. coli one month before delivering, which resolved without complications using nitrofurantoin. There was no history of maternal herpes simplex infection and her serologic screening was negative for syphilis.

[Motor vehicles and ultraviolet exposure in Mexico]. / Automóviles y exposición ultravioleta en México.

INTRODUCTION: Sun exposure can cause both acute and chronic lesions of the skin due to ultraviolet (UV) radiation. While driving or traveling inside a vehicle, a person is exposed to this radiation, which can induce or exacerbate certain dermatoses. OBJECTIVE: To determine if the window glasses of commercial vehicles in Mexico can block UV transmission or if the addition of tinted films is necessary. MATERIAL AND METHODS: Sixty models of vehicles manufactured between 1998 and 2011 were randomly selected. UVA and UVB were measured through the windshield and lateral window glasses, and their transmission was calculated compared to ambient UV radiation. Four commercial tinted films were also evaluated for UV transmission. RESULTS: The average UVB transmission from the windshield was 0.01% and 0.9% for UVA. For the driver's and front seat's glasses, UVB transmission was 2% and 16% for UVA. Tinted films transmitted less than 4.5% of UVA, and almost 0% of UVB. CONCLUSIONS: Driving with the vehicle's windows closed eliminates 98% of UVB and 84% of UVA. Therefore, the addition of tinted films provides a marginal benefit in most clinical conditions that manifest photosensibility.

[Solar exposure time for sunburn in Mexican population]. / Estimación del tiempo de exposición solar para quemadura en población mexicana.

INTRODUCTION: THe minimal erythemal dose (MED) quantifies an individual's sensitivity to UV radiation (UVR). To estimate it in our population and establish the time of exposure inducing it during daily activities would allow us to calculate risk intervals. METHODS: From 2005-2012, the UV solar radiation was measured with terrestrial radiometry and compared to public UV index (UVI). We determined the MED in 90 individuals with the prevalent phototypes in Mexico (III, IV, V), and estimated the time needed for the development of sunburn. RESULTS: The average MED for phototype III was 39 (IC 95%: 35-42) mJ/cm2, for IV 48 (IC 95%:42-53) mJ/cm2, and for V was 84 (IC 95%:75-92) mJ/cm2 (ANOVA, p ≤ 0.001). Approximately, 80% of the daily UVR was accumulated between 10:00-16:00 h, and 77% of the annual UV dose is received between March-October. The public UVI had a high correlation with the one quantified at terrestrial level (r = 0.89; p ≤ 0.001). CONCLUSIONS: Mexico receives continuously high levels of UVR. Phototype III will present sunburn after 22-33 min in a summer day, while phototype V will require over one hour of exposure. This last group is at risk of chronic exposure without considering consequences.

[Assessment of moisturizing creams available in México]. / Evaluación de cremas humectantes disponibles en México.

UNLABELLED: There is a broad diversity of moisturizers for the treatment of dry skin; however, we do not know their real effectiveness. The objective here was to evaluate different products through their capacity to increase the epidermal hydration level (EHL) and to reduce the transepidermal water loss (TEWL). MATERIALS AND METHODS: We evaluated twenty moisturizers in sixteen individuals. The analysis was made on volar forearm and basal measurements were made for EHL and TWEL with the later application of 8 gm of each moisturizer on a 2 cm2 area. RESULTS: For the EHL we found significant differences among the products (p < 0.0001), but only 35% (n = 7) of the moisturizers registered ascending levels of hydration in the course of measurements. The variance analysis for TEWL also was significant (p < 0.0001). CONCLUSIONS: In the short term only a few products induced a significant change in EHL. This study demonstrates the necessity to obtain objective information in order to avoid false publicity claims that may erroneously influence our prescription habits.

In vitro determination of the chromatic effect of a silver nanoparticles solution linked to the gantrez S-97 copolymer on tooth enamel.

Silver nanoparticles (NNPs), alone or in combination with the bioadhesive Gantrez S-97, have demonstrated their efficacy against Streptococcus mutans; however, it is not known if this combination changes the color of teeth. The aim of this work was to measure the color changes occurring after the use of a Gantrez-NNP combination on enamel tooth blocks. Two study groups were randomly formed: enamel blocks brushed with (a) the Gantrez-NNP combination and (b) conventional toothpaste, for 1 minute once daily for 4 weeks, then rinsed with distilled water and placed in thymol solution. Color changes in the enamel blocks were measured using a Minolta colorimeter CR300. Analysis of mixed models was performed with R 2.10.1 at a 95% confidence level, using the nonlinear mixed effects (NLME) package. The results showed that there were no color changes over time, only a high luminosity equal in both groups. Our study showed that the use of the Gantrez-NNP combination is safe with respect to dental esthetics in the control of S. mutans.

Clinical efficacy of 5% sodium hypochlorite for removal of stains caused by dental fluorosis.

The objective of this study was to evaluate the clinical efficacy of 5% sodium hypochlorite solution for removal of stains caused by dental fluorosis in young patients. A clinical trial involved 33 patients with diffuse opacities on the enamel surfaces of maxillary incisors due to effects of dental fluorosis. The protocol of treatment 3 steps: (1) cleaning and enamel etching with 37% phosphoric acid in order to eliminate the layer that covers the fluorotic enamel surface and allow better penetration of the bleaching agent, (2) application of 5% sodium hypochlorite to remove stains caused by organic material, and (3) filling the opened micro-cavities with a light-cured, composite surface sealant to prevent restaining. The whiteness of the enamel lesions before and after treatment were expressed in L*, a*, and b* color space measurements using a Minolta Chroma Meter CR300. Analysis of parameters of [symbol:see text]E (L*, a*, b*) showed that changes were observed in the L* (brightness) and a* (redness), which paralleled the [symbol: see text]E differences. There was no significant difference in the b* (yellow) parameter. The technique described in this study appears to have advantages over other methods for improving the appearance of fluorotic lesions. It is simple, low cost, non invasive so the enamel keeps its structure, relatively rapid, and safe; it requires no special materials, and it can be used with safety on young permanent teeth.

DNA Methyltransferases in Malar Melasma and Their Modification by Sunscreen in Combination with 4% Niacinamide, 0.05% Retinoic Acid, or Placebo.

BACKGROUND: Malar melasma has a chronic and recurrent character that may be related to epigenetic changes. OBJECTIVE: To recognize the expression and DNA methylation of DNA methyltransferases (DNMTs) in malar melasma and perilesional skin, as well as the changes in DNMTs after their treatment with sunscreen in combination with 4% niacinamide, 0.05% retinoic acid, or placebo. METHODS: Thirty female patients were clinically evaluated for the expression of DNMT1 and DNMT3b using real-time PCR and immunofluorescence. These initial results were compared to results after eight weeks of treatment with sunscreen in combination with niacinamide, retinoic acid, or placebo. RESULTS: The relative expression of DNMT1 was significantly elevated in melasma compared with unaffected skin in all subjects, indicating DNA hypermethylation. After treatment, it was decreased in all groups: niacinamide (7 versus 1; p<0.01), retinoic acid (7 versus 2; p<0.05), and placebo (7 versus 3; p<0.05), which correlates with clinical improvement. DNMT3b was not overexpressed in lesional skin but reduced in all groups. CONCLUSIONS: We found DNA hypermethylation in melasma lesions. Environmental factors such as solar radiation may induce cellular changes that trigger hyperpigmentation through the activation of pathways regulated by epigenetic modifications. However, limiting or decreasing DNA methylation through sunscreen, niacinamide, and retinoic acid treatments that provide photoprotection and genetic transcription can counteract this.

[Ultraviolet absorption of prescription sunblocks in Mexico]. / Absorción ultravioleta de los protectores solares para prescripción en México.

BACKGROUND: An appropriate sunscreen should provide high and broad ultraviolet protection both for the B and A range. The objective was quantify the ultraviolet absorption spectrum in sunscreens available for medical prescription, and analyze its relationship with the labeled Sun Protection Factor (SPF). MATERIAL AND METHODS: Thirty-nine sunscreens were analyzed in vitro using ultraviolet spectroscopy following exposure to simulated solar irradiation. RESULTS: Fifty-six percent of sunscreens absorbed 90% or more of ultraviolet radiation. Seventy-five percent (n = 34) absorbed more than 95% of ultraviolet B radiation, and 46% (n = 18) more than 90% of ultraviolet A. There was no significant association between ultraviolet absorption and SPF. CONCLUSION: We were unable to estimate ultraviolet absorption only by its SPF. Protection differed considerably among products with similar SPF. Our study highlights regulation deficiencies in marketing practices of these products.

A Case of Prostatic Carcinoma Manifesting as Cutaneous Facial Nodule.

Prostate cancer is the second most frequently diagnosed cancer worldwide and the fifth most common cause of cancer deaths among men. Cutaneous metastasis is an uncommon phenomenon in prostatic cancer, occurring in 0.06-0.3% of cases. Case Presentation. A 56-year-old man presented to our outpatient clinic with a one-month history of a 1.5 cm in diameter, solitary, asymptomatic, purple nodule located on his upper right cheek. After biopsy, prostatic cancer metastasis was diagnosed. Discussion. A literature review revealed 59 articles documenting 71 cases of this diagnosis. The review recorded epidemiological data, including age, duration, morphology, location, and outcome of patients. Conclusions. The skin is an uncommon site for metastasis of prostate cancer, and the review showed that its presence is associated with a poor prognosis (approximately 10 months from diagnosis).

[Knowledge and attitudes of Mexican population concerning solar radiation]. / Conocimientos y actitudes de la población mexicana con respecto a la radiación solar.

BACKGROUND: The effects of solar radiation in human health is dependent upon environment, behavior, and genetic characteristics. OBJECTIVE: Identify phenotypic features, attitudes, knowledge and preventive measures concerning sun exposure among a local population. METHODS: People older than 15 years were interviewed concerning time of sun exposure, photoprotection, and general knowledge about adverse effects of sun irradiation. RESULTS: 964 questionnaires were analyzed. White-skin population represented 7.4%, light-brown 24.8%, dark-brown 67.8%. Exposure time on working days was up to 15 min in 27.8%, and more than 60 min in 38.8%. On weekends, time exposure was similar. 30% did not take any preventive measures 41% wore hats and 11.8% used sunscreens. Among participants, 85.4% were aware that sun exposure caused skin cancer, 64. 1% knew that mortality is increased, 83.4% reported that excessive sun exposure is related to aging of the skin, and 26.5% believed tanning is healthy. CONCLUSIONS: In spite of thefact that a great majority of the population recognized that sun exposure produces aging and skin cancer, their exposure is widespread. This survey may be a valuable tool to design preventive public health campaigns that target high risk groups.