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Trichoscopy (dermoscopy of the hair and scalp) is a technique that improves diagnostic accuracy and follow-up with hair and scalp disorders. Although several studies of trichoscopy have been made in Caucasian and Asian populations, little has been published regarding trichoscopy findings in skin of color, despite the great prevalence of hair diseases in populations with this kind of skin. The aim of this review was to describe the trichoscopic features of normal scalp and of hair disorders in patients with dark skin phototypes. This will help dermatologists to distinguish between unique trichoscopic features of dark skin, and allow them to provide more accurate diagnoses and treatments for these patients.

BACKGROUND Mycobacterium tuberculosis is an intracellular pathogen, which may either block cellular defensive mechanisms and survive inside the host cell or induce cell death. Several studies are still exploring the mechanisms involved in these processes. OBJECTIVES To evaluate the genomic instability of M. tuberculosis-infected macrophages and compare it with that of uninfected macrophages. METHODS We analysed the possible variations in the genomic instability of Mycobacterium-infected macrophages using the DNA breakage detection fluorescence in situ hybridisation (DBD-FISH) technique with a whole human genome DNA probe. FINDINGS Quantitative image analyses showed a significant increase in DNA damage in infected macrophages as compared with uninfected cells. DNA breaks were localised in nuclear membrane blebs, as confirmed with DNA fragmentation assay. Furthermore, a significant increase in micronuclei and nuclear abnormalities were observed in infected macrophages versus uninfected cells. MAIN CONCLUSIONS Genomic instability occurs during mycobacterial infection and these data may be seminal for future research on host cell DNA damage in M. tuberculosis infection. Key words: Mycobacterium tuberculosis - alkaline-labile sites - DNA breakage detection fluorescence in situ hybridisation (DBD-FISH)

Cherriesarefruitscontainingfiberandbioactivecompounds(e.g.,polyphenolics)with the potential of helping patients with diabetes and weight disorders, a phenomenon likely related to changes in the complex host-microbiota milieu. The objective of this study was to investigate the effect of cherry supplementation on the gut bacterial composition,concentrationsofcaecalshort-chainfattyacids(SCFAs)andbiomarkers ofguthealthusinganinvivomodelofobesity.Obesediabetic(db/db)micereceiveda supplementeddietwith10%cherrypowder(supplementedmice,n=12)for12weeks; obese (n=10) and lean (n=10) mice served as controls and received a standard diet without cherry. High-throughput sequencing of the 16S rRNA gene and quantitative real-timePCR(qPCR)wereusedtoanalyzethegutmicrobiota;SCFAsandbiomarkers of gut health were also measured using standard techniques. According to 16S sequencing, supplemented mice harbored a distinct colonic microbiota characterized by a higher abundance of mucin-degraders (i.e., Akkermansia) and fiber-degraders (theS24-7family)aswellaslowerabundancesofLactobacillusandEnterobacteriaceae. Overall this particular cherry-associated colonic microbiota did not resemble the microbiotainobeseorleancontrolsbasedontheanalysisofweightedandunweighted UniFracdistancemetrics.qPCRconfirmedsomeoftheresultsobservedinsequencing, thussupportingthenotionthatcherrysupplementationcanchangethecolonicmicrobiota.Moreover,theSCFAsdetectedinsupplementedmice(caproate,methylbutyrate, propionate, acetate and valerate) exceeded those concentrations detected in obese and lean controls except for butyrate. Despite the changes in microbial composition and SCFAs, most of the assessed biomarkers of inflammation, oxidative stress, and intestinal health in colon tissues and mucosal cells were similar in all obese mice with and without supplementation. This paper shows that dietary supplementation with cherry powder for 12 weeks affects the microbiota and the concentrations of SCFAs in the lower i

For a better view of the nail matrix during nail surgery, the proximal nail fold (PNF) must be incised and reclined. Two oblique incisions at 45° at the junction of the proximal and lateral nail fold are performed [1, 2]. As the nail matrix is just below the PNF, there is a considerable risk of hurting the matrix, and consequently nail dystrophy

Background: Vitiligo is characterized by a lack of pigmentation in the skin. To date, there are no studies that analyze the changes in gene expression in the skin of vitiligo patients in response to narrow-band ultraviolet B (nb-UVB) phototherapy treatment. oBjective: Explore the usefulness of new generation RNA sequencing in the identification of gene expression changes in the skin of vitiligo patients treated with nb-UVB phototherapy. Methods: Four skin biopsies (4mm in diameter) were collected from 45 Mexican vitiligo vulgaris patients, 2 specimens before and 2 after treatment with nb-UVB phototherapy, obtained from pigmented and non-pigmented tissue. RNA extracted from the biopsies was analyzed using the Illumina TruSeq Targeted RNA Expression protocol to study the expression of genes that participate in pathways of skin homeostasis. The 2 groups were compared using Student’s t-test and the Mann-Whitney U-test. results: The expression analysis identified differences in 12 genes included in this study after comparing the samples obtained before and after treatment: 5 genes involved in skin pigmentation, 2 genes involved in apoptosis, 2 genes involved in cell survival, 2 genes involved in oxidative stress responses and 1 gene involved in signal transduction mechanisms (p<0.05). study liMitations: The small size of skin biopsies limits the amount of RNA obtained, the number of genes to be analyzed and the use of conventional techniques such as RT-qPCR. conclusion: We demonstrated usefulness of new generation RNA sequencing in the identification of gene expression changes, in addition to identifying new targets in the study of vitiligo. Keywords: Gene expression; Phototherapy; Vitiligo

Vitiligo is a disorder causing skin depigmentation, in which several factors have been proposed for its pathogenesis: Environmental, genetic and biological aspects of melanocytes, even those of the surrounding keratinocytes. However, the lack of understanding of the mechanisms has complicated the task of predicting the development and progression. The present study used microarray analysis to characterize the transcriptional profile of skin from Vitiligo Vulgaris (VV) patients and the identified transcripts were validated using targeted high-throughput RNA sequencing in a broader set of patients. For microarrays, mRNA was taken from 20 skin biopsies of 10 patients with VV (pigmented and depigmented skin biopsy of each), and 5 biopsies of healthy subjects matched for age and sex were used as a control. A signature was identified that contains the expression pattern of 722 genes between depigmented vitiligo skin vs. healthy control, 1,108 between the pigmented skin of vitiligo vs. healthy controls and 1,927 between pigmented skin, depigmented vitiligo and healthy controls (P<0.05; false discovery rate, <0.1). When comparing the pigmented and depigmented skin of patients with vitiligo, which reflects the real difference between both skin types, 5 differentially expressed genes were identified and further validated in 45 additional VV patients by RNA sequencing. This analysis showed significantly higher RNA levels of calpain-3, dopachrome tautomerase, melan-A and tyrosinase-related protein-1 genes. The data revealed that the pigmented skin of vitiligo is already affected at the level of gene expression and that the main differences between pigmented and non-pigmented skin are explained by the expression of genes associated with pigment metabolism.

El borrego cimarrón del desierto (Ovis canadensis) es una especie con una distribución espacial restringida, debido a que requiere de características específicas de hábitat que le provean agua, alimento, cobertura y espacio; factores determinantes en la selección de sitios de distribución. O. c. weemsi tiene el estatus de especie Sujeta a Protección Especial y, actualmente, solo se ha registrado en algunas zonas de Sonora, Baja California y Baja California Sur. La Isla El Carmen, Baja California Sur, pertenece al Parque Marino Nacional Bahía de Loreto, por su ubicación geográfica, condiciones climáticas, escasez de agua, tipos de vegetación y topoformas es un sitio de enorme interés para realizar investigaciones en ecosistemas de zonas áridas. Se determinó la distribución del borrego cimarrón (O c. weemsi) introducido en la Isla, mediante el método de conteo por franjas, modificado por Hayne; y el registro a través de avistamiento de ejemplares en los aguajes, para reforzar las observaciones de la estructura poblacional de la especie. Asimismo, se registraron la inclinación del terreno, época del año, distribución de aguajes y presencia de comederos para determinar su efecto en la estructura de la población. Se estimó una densidad de 4.96 borregos km-2, con un total de 1 151 observaciones. Se calcularon 616 individuos en una superficie de 12 428 ha con matorral desértico sarcocaule.

Ecthyma gangrenosum is a rare skin infection classically associated with Pseudomonas aeruginosa. We performed a retrospective study of all cases diagnosed with ecthyma gangrenosum from 2004-2010 in a university hospital in Mexico (8 cases, 5 female patients and 3 male patients, ages between 4 months and 2 years). The most common risk factor for ecthyma gangrenosum is neutropenia in immunocompromised patients. In previously healthy patients, immunological evaluation is important to rule out underlying immunodeficiency. Ecthyma gangrenosum in healthy patients has a high mortality rate and early diagnosis and aggressive antibiotic treatment is imperative as it can improve patients’ prognosis. Keywords: Ecthyma; Pseudomonas; Pseudomonas aeruginosa; Pseudomonas infections

Acute hemorrhagic edema of infancy was initially described in 1913 by Snow. It is a benign, self-limited leukocytoclastic vasculitis that occurs most commonly in males. It evolves favorably with conservative medical management and treatment with steroids is not usually administered.

Onychomatricoma (OM) presenting as a longitudinal melanonychia is a very uncommon clinical presentation with very few cases in the literature. Our aim in this article is to report four cases of pigmented OM, and describe their clinical and dermoscopic findings and the importance of the differential diagnoses, especially with melanoma. Key words: longitudinal melanonychia, nail, nail tumour, onychomatricoma, pigmented onychomatricoma.