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el pioderma canino corresponde a la contaminación bacteriana de la piel, causada en mayor parte de los casos por Staphylococcus pseudointermedius. Durante las últimas décadas los Staphylococcus sp. han mostrado una mayor resistencia a los antimicrobianos, en medicina humana y veterinaria. El objetivo del presente estudio fue determinar el perfil de sensibilidad “in vitro” de Staphylococcus sp. aislados en muestras de pioderma canino en la ciudad de Popayán. Fueron colectadas 34 muestras de caninos diagnosticados con pioderma en clínicas y refugios, cultivadas en medio de agar sangre 5% e incubadas a 37°C. Colonias aisladas se clasificaron por métodos bioquímicos: catalasa, manitol, fermentación de maltosa, glucosa y sacarosa. El perfil de sensibilidad fue evaluado por el método de difusión en discos con los antibióticos ceftriaxona, cefalexina, amoxicilina con ácido clavulánico, doxiciclina, clindamicina y sulfa/trimetoprim, clasificando a los estafilococos como sensibles, intermedios o resistentes con referencia en los valores del Clinical and Laboratory Standard Institute. En 38% de las muestras cultivadas (n=13) fue aislado S. pseudointermedius, 18% (n=6) S. epidermidis, 15% (n=5) S. intermedius, 12% (n=4) S. aureus y en 18% (n=6) otros estafilococos. Respecto al perfil de sensibilidad “in vitro”, en términos generales se observó una mayor resistencia frente a clindamicina (68%), cefalexina (68%), amoxicilina/ácido clavulánico (59%) y ceftriaxona (56%). Respecto al patógeno más resistente, S. pseudointermedius mostró una resistencia en 6/13 aislados para todos los antibióticos evaluados, seguido de S. epidermidis con 5/6 aislados y S. intermedius con 3/5 aislados. S. aureus, S. y Staphylococcus spp. mostraron igual proporción de muestras resistente y sensibles dentro del total de aislados. El uso de pruebas específicas como cultivo y antibiograma es útil para identificar el patógeno causante y establecer una antibioterapia adecuada.

Chromoblastomycosis is a chronic cutaneous and subcutaneous mycosis, is caused by dematiaceous fungi, the most frequently implicated are Fonsecaea, Phialophora, Cladophialophora, Rhinocladiella and Exophiala.We report a woman who was treated before with mycological cure, but she experience a relapse requiring treatment again. Direct microscopic examination and skin biopsy with culture were necessary to identify a Exophiala psychrophila, and for our knowledge this is the first case reported. Keywords: Chromoblastomycosis, Exophiala salmonis-clade, Subcutaneous mycosis

La resistencia a antimicrobianos representa un aspecto natural de evolución bacteriana, que puede resultar de mutaciones o por adquisición de genes foráneos. Hay diferentes posturas sobre el origen de ésta resistencia que explican la habilidad de estos microorganismos de adquirir nuevas características. Las teorías de la evolución de Lamarck y Darwin, han dado pie a experimentos diseñados para explorar el origen de la variación bacteriana y surgimiento de nuevas características. Estos estudios muestran que la resistencia está relacionada con mutaciones en genes cromosomales y/o la transferencia de elementos genéticos extracromosomales, que se expresan según la presión antibiótica ejercida. Está revisión recopila los principales experimentos y las conclusiones derivadas para explicar el fenómeno de resistencia a antibióticos. Antimicrobial resistance is a natural aspect of bacterial evolution that can result from mutations or acquisition of foreign genes. Various views on the origin of this resistance explain the ability of these organisms to acquire new features. Lamarck andDarwin’s theories of evolution have led to experiments designed to explore the origin of bacterial variation and the emergence of new features. These experiments show that antimicrobial resistance is related to mutations in chromosomal genes and/or transfer of extrachromosomal genetic elements that can be expressed based on the antibiotic pressure exerted. The main experiments and findings that seek to explain the phenomenon of antibiotic resistance are reviewed here in.

Genotyping of Fusarium Isolates from Onychomycoses in Colombia: Detection of Two New Species Within the Fusarium solani Species Complex and In Vitro Antifungal Susceptibility Testing DOI: 10.1007/s11046-016-9983-9 URL: http://link.springer.com/article/10.1007%2Fs11046-016-9983-9 Fusariosis have been increasing in Colombia in recent years, but its epidemiology is poorly known. We have morphologically and molecularly characterized 89 isolates of Fusarium obtained between 2010 and 2012 in the cities of Bogotá and Medellín. Using a multi-locus sequence analysis of rDNA internal transcribed spacer, a fragment of the translation elongation factor 1-alpha (Tef-1α) and of the RNA-dependent polymerase subunit II (Rpb2) genes, we identified the phylogenetic species and circulating haplotypes. Since most of the isolates studied were from onychomycoses (nearly 90 %), we carried out an epidemiological study to determine the risk factors associated with such infections. Five phylogenetic species of the Fusarium solani species complex (FSSC), i.e., F. falciforme, F. keratoplasticum, F. lichenicola, F. petroliphilum, and FSSC 6 as well as two of the Fusarium oxysporum species complex (FOSC), i.e., FOSC 3 and FOSC 4, were identified. The most prevalent species were FOSC 3 (38.2 %) followed by F. keratoplasticum (33.7 %). In addition, our isolates were distributed into 23 haplotypes (14 into FOSC and nine into FSSC). Two of the FSSC phylogenetic species and two haplotypes of FSSC were not described before. Our results demonstrate that recipients of pedicure treatments have a lower probability of acquiring onychomycosis than those not receiving such treatments. The antifungal susceptibility of all the isolates to five clinically available agents showed that amphotericin B was the most active drug, while the azoles exhibited lower in vitro activity.

Resumen Introduccion Globalamente la situacion epidemiologica de la enfermedad por micobacterias no tuberculosas (MNT) es desconocida debido a que no es una enfermedad de notificacion en la mayoria de los paises, sin embargo los diversos reportes de infecciones y brotes por MNT publicados sugieren su creciente incremento en los ultimos anos. Tradicionalmente la identificacion se realiza a traves de metodologias bioquimicas, las cuales permiten la diferenciacion inicial entre M. tuberculosis y MNT, y en algunos casos la identificacion de la especie micobacteriana. Sin embargo, esta metodologia tiene importantes limitaciones tecnicas y la obtencion de resultados requiere tiempos prolongados. Por otra parte, la introduccion de metodologias basadas en biologia molecular ha facilitado significativamente el diagnostico de las MNT desde el laboratorio. Objetivo Establecer la frecuencia de MNT en los cultivos positivos para bacilos acido alcohol resistentes remitidos al Laboratorio de Salud publica de Bogota en un periodo de 12 meses. Materiales y metodos Un total de 100 cultivos provenientes de hospitales publicos y privados de Bogota fueron identificados a traves de pruebas bioquimicas y de las metodologias moleculares; PRA (PCR-analisis de restriccion) y PCR multiplex. Asi mismo, la presencia de especies de baja prevalencia, asi como el estudio de los casos no concluyentes se realizo traves de analisis de secuenciacion del blanco molecular 16SrDNA. Resultados El estudio identifico MNT en el 11% de los cultivos a traves de la metodologia PRA. Adicionalmente, esta metodologia molecular permitio detectar la ocurrencia de mas de una especie micobacteriana en el 4% de los cultivos evaluados. Interesantemente un nuevo patron de restriccion-PRA para la especie M. kubicae es reportado en nuestro estudio. Conclusion El uso de un algoritmo de identificacion micobacteriana que incluya la metodologia molecular PRA incrementa el poder diagnostico de los metodos convencionales, y contribuye al mejor conocimiento de la epidemiologia de las MNT y control de las micobacteriosis.

The efficacy of liposomal amphotericin B and voriconazole was evaluated against the systemic infection by Fusarium oxysporum species complex or Fusarium keratoplasticum. Although MIC values were within the epidemiological cutoff values (ECVs) recently stablished for Fusarium spp., no efficacy was obtained, indicating that ECVs for Fusarium are not relevant for in vivo efficacy.

Resumen La resistencia a antimicrobianos representa un aspecto natural de evolución bacteriana, que puede resultar de mutaciones o por adquisición de genes foráneos. Hay diferentes posturas sobre el origen de ésta resistencia que explican la habilidad de estos microorganismos de adquirir nuevas características. Las teorías de la evolución de Lamarck y Darwin, han dado pie a experimentos diseñados para explorar el origen de la variación bacteriana y surgimiento de nuevas características. Estos estudios muestran que la resistencia está relacionada con mutaciones en genes cromosomales y/o la transferencia de elementos genéticos extracromosomales, que se expresan según la presión antibiótica ejercida. Está revisión recopila los principales experimentos y las conclusiones derivadas para explicar el fenómeno de resistencia a antibióticos. Abstract Antimicrobial resistance is a natural aspect of bacterial evolution that can result from mutations or acquisition of foreign genes. Various views on the origin of this resistance explain the ability of these organisms to acquire new features. Lamarck and Darwin’s theories of evolution have led to experiments designed to explore the origin of bacterial variation and the emergence of new features. These experiments show that antimicrobial resistance is related to mutations in chromosomal genes and/or transfer of extrachromosomal genetic elements that can be expressed based on the antibiotic pressure exerted. The main experiments and findings that seek to explain the phenomenon of antibiotic resistance are reviewed here in.

Malassezia furfur is part of the human skin microbiota. Its volatile organic compounds (VOCs) possibly contribute to the characteristic odour in humans, as well as to microbiota interaction. The aim of this study was to investigate how the lipid composition of the liquid medium influences the production of VOCs. Growth was performed in four media: (1) mDixon, (2) oleic acid (OA), (3) oleic acid + palmitic acid (OA+PA), and (4) palmitic acid (PA). The profiles of the VOCs were characterized by HS-SPME/GC-MS in the exponential and stationary phases. A total number of 61 VOCs was found in M. furfur, among which alkanes, alcohols, ketones, and furanic compounds were the most abundant. Some compounds previously reported for Malassezia (&gamma, dodecalactone, 3-methylbutan-1-ol, and hexan-1-ol) were also found. Through our experiments, using univariate and multivariate unsupervised (Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA)) and supervised (Projection to Latent Structures Discriminant Analysis (PLS-DA)) statistical techniques, we have proven that each tested growth medium stimulates the production of a different volatiles profile in M. furfur. Carbon dioxide, hexan-1-ol, pentyl acetate, isomer5 of methyldecane, dimethyl sulphide, undec-5-ene, isomer2 of methylundecane, isomer1 of methyldecane, and 2-methyltetrahydrofuran were established as differentiating compounds among treatments by all the techniques. The significance of our findings deserves future research to investigate if certain volatile profiles could be related to the beneficial or pathogenic role of this yeast.

Four new zinc complex derivatives of azoles and ligands were synthesized and isolated as white air-stable solids and characterized by elemental analyses, thermogravimetric analysis (TGA), infrared spectroscopy, nuclear magnetic resonance (NMR) and mass spectra. The elemental analysis, theoretical calculations and NMR show that the complexes likely have a 1:1 (M:L) stoichiometry and tetrahedral geometry. To evaluate the biological activity of the complexes and to discuss the role of metal ions and structural properties, the ligands and their metal complexes have been studied. Their antimicrobial activity was determined in vitro by agar-well diffusion and broth microdilution against nine bacterial strains and seven fungal strains with clinical relevance. In vitro assays showed that the complexes exhibited moderate antibacterial and/or antifungal activities. The antimicrobial activity was found to be more active for the metal complexes than the ligands. The metal complexes that contained copper and cobalt, respectively, displayed notable antibacterial and antifungal effects against all the tested bacterial strains. The minimum inhibitory concentration 50 (MIC50) values were in the range 2454-0.7 µg mL-1. Metal complexes were more effective at inhibiting bacteria than fungi. The results could provide a high-potential solution for antimicrobial growth resistance, for both bacteria and fungi.

The species constituting the genus Malassezia are considered to be emergent opportunistic yeasts of great importance. Characterized as lipophilic yeasts, they are found in normal human skin flora and sometimes are associated with different dermatological pathologies. We have isolated seven Malassezia species strains that have a different Tween assimilation pattern from the one typically used to differentiate M. furfur , M. sympodialis , and M. slooffiae from other Malassezia species. In order to characterize these isolates of Malassezia spp., we studied their physiological features and conducted morphological and molecular characterization by PCR-restriction fragment length polymorphism and sequencing of the 26S and 5.8S ribosomal DNA-internal transcribed spacer 2 regions in three strains from healthy individuals, four clinical strains, and eight reference strains. The sequence analysis of the ribosomal region was based on the Blastn algorithm and revealed that the sequences of our isolates were homologous to M. furfur sequences. To support these findings, we carried out phylogenetic analyses to establish the relationship of the isolates to M. furfur and other reported species. All of our results confirm that all seven strains are M. furfur ; the atypical assimilation of Tween 80 was found to be a new physiological pattern characteristic of some strains isolated in Colombia.

Malassezia pachydermatis is a basidiomycetous yeast that causes infections in humans and animals. Here, we report the genome sequence of Malassezia pachydermatis strain CBS 1879, which will facilitate the study of mechanisms underlying pathogenicity of the only non-lipid-dependent Malasezzia species.

Introduccion. Las especies del genero Malassezia se consideran levaduras oportunistas emergentes de gran importancia. Han sido asociadas a diferentes patologias dermatologicas y sistemicas de las cuales se aislan una o mas especies de este genero. El papel de estas levaduras en las enfermedades dermatologicas no se ha aclarado completamente, ya que la Malassezia spp. pertenece a la flora normal de la piel. Objetivo. Buscar marcadores geneticos en los aislamientos de Malassezia spp. que permitan correlacionar las lesiones dermatologicas con las especies aisladas. Materiales y metodos. Se obtuvieron 103 aislamientos de Malassezia spp. a partir de muestras de pacientes con pitiriasis versicolor, dermatitis seborreica, dermatitis seborreica en pacientes positivos para VIH, dermatitis atopica, y de individuos sanos. Para los controles se usaron ocho cepas del Centraalbureau voor Schimmelcultures (CBS), Holanda. El perfil genetico se realizo utilizando la tecnica de ADN polimorfico amplificado aleatorio (RAPD) con tres iniciadores (OPA2, OPA4, OPA13). Los datos obtenidos se analizaron con los programas Diversity Database y SYN-TAX-PC. Resultados. Se observo heterogeneidad genetica intraespecifica en Malassezia furfur, Malassezia globosa, Malassezia restricta, Malassezia slooffiae y Malassezia obtusa, mientras que Malassezia sympodialis mostro mayor homogeneidad. Conclusion. No se determino ningun patron genetico especifico mediante la tecnica de RAPD para las especies de Malassezia que se pudiera relacionar con la entidad dermatologica implicada.

Introduction. Yeasts of the genus Malassezia form a normal component of skin flora, but are also associated with several dermatological disorders. Since 1996, the description of new species in this genus have led to new questions about their epidemiology and pathogenicity. Objective. Herein, the frequency of Malassezia species in individuals with pityriasis versicolor, atopic dermatitis, seborrhoeic dermatitis, seborrhoeic dermatitis was compared in HIV patients and healthy individuals. Three body sites were selected for examination -head, thorax, and upper and lower extremities. Material and methods. The 154 Malassezia species were isolated from 112 individuals and grouped as follows: 39 with seborrhoeic dermatitis (20 were HIV-positive patients), 18 with pityriasis versicolor, 18 with atopic dermatitis and 37 without dermatological leisions. HIV patient samples were examined microscopically, and specimens from both patients and healthy subjects were cultured on modified Dixon agar medium. Subsequently, isolates were identified by macroscopic, microscopic and physiological characteristics. Results. The most commonly isolated species were Malassezia globosa (37.5%), M. sympodialis (31.3%) and M. furfur (31.3%). Malazzerzia globosa predominated in patients with pityriasis versicolor (67%) and in HIV-positive patients with seborrhoeic dermatitis (85%). In non-HIV patients with atopic dermatitis or seborrhoeic dermatitis, M. furfur and M. restricta were isolated in 72% and 26% of the cases, respectively. Conclusion. Several conclusions were evident. First, Malassezia species was present in subjects with and without dermatological pathologies. Second, the species frequency in the sampled population differed from frequencies reported from other geographic areas. Third, Malassezia globosa was involved at high frequency in patients with dermatological pathologies, suggesting a higher pathogenicity of this species. Additional studies on each species are recommended to clarify their pathogenic roles in association with HIV-positive and normal subjects. Introducción. Las levaduras del género Malassezia forman parte de la flora normal de la piel y se asocian con varios tipos de lesiones dermatológicas. Desde 1996, la descripción de nuevas especies dentro de este género planteó numerosos interrogantes sobre su epidemiología y patogenicidad. Objetivo. El fin de este trabajo fue encontrar la frecuencia de las diferentes especies de Malassezia en individuos con pitiriasis versicolor, dermatitis atópica, dermatitis seborreica, dermatitis seborreica en pacientes positivos para VIH, y en individuos sin lesiones a partir de tres zonas corporales (cabeza, tórax, extremidades inferiores y superiores). Materiales y métodos. Se identificaron 154 aislamientos de especies de Malassezia de 112 individuos: 39 con dermatitis seborreica de los cuales 20 eran positivos para VIH, 18 con pitiriasis versicolor, 18 con dermatitis atópica y 37 individuos sin lesión dermatológica (controles). Las escamas de piel de los pacientes se observaron microscópicamente y las muestras de pacientes y controles se cultivaron en agar Dixon modificado. Posteriormente, se observaron las colonias y se identificaron según sus características macroscópicas, microscópicas y fisiológicas. Resultados. Las especies más frecuentemente aisladas en el total de los grupos estudiados fueron: Malassezia globosa (37,5%), M. sympodialis (31,3%) y M. furfur (31,3%). M. globosa predominó en los aislamientos de pacientes con pitiriasis versicolor (67%) y en pacientes positivos para VIH con dermatitis seborreica (85%). En pacientes con dermatitis atópica y dermatitis seborreica sin diagnóstico de VIH, se aislaron M. furfur y M. restricta en el 72% y el 26% de los casos, respectivamente. Conclusiones. Las diferentes especies de Malassezia pueden aislarse de pacientes con lesiones dermatológicas o sin ellas. Además, la frecuencia de especies en la población muestreada difiere de lo reportado en otras zonas geográficas. Se destaca la alta frecuencia de M. globosa en pacientes con lesiones lo que podría indicar la mayor patogenicidad de esta especie. No obstante, se requieren estudios adicionales para determinar el papel de las diferentes especies del género Malassezia, asociadas con estas patologías.

Global epidemiology of non-tuberculous mycobacteria (NTM) is unknown due to the fact that notification is not required in many countries, however the number of infection reports and outbreaks caused by NTM suggest a significant increase in the last years. Traditionally, mycobacteria identification is made through biochemical profiles which allow to differentiate M. tuberculosis from NTM, and in some cases the mycobacteria species. Nevertheless, these methods are technically cumbersome and time consuming. On the other hand, the introduction of methods based on molecular biology has improved the laboratory diagnosis of NTM.To establish the NTM frequency in positive cultures for acid-fast bacilli (AAFB) which were sent to Laboratorio de Salud Pública de Bogotá over a 12 month period.A total of 100 positive cultures for acid-fast bacilli from public and private hospitals from Bogotá were identified by both biochemical methods and the molecular methods PRA (PCR-restriction enzyme analysis) and multiplex-PCR. Furthermore, low prevalence mycobacteria species and non-interpretable results were confirmed by 16SrDNA sequentiation analysis.Identification using the PRA method showed NMT occurrence in 11% of cultures. In addition, this molecular methodology allowed to detect the occurrence of more than one mycobacteria in 4% of the cultures. Interestingly, a new M. kubicae pattern of PCR-restriction analysis is reported in our study.Using a mycobacteria identification algorithm, which includes the molecular method PRA, improves the diagnostic power of conventional methods and could help to advance both NTM epidemiology knowledge and mycobacteriosis control.

Seborrheic dermatitis (SD) is a chronic, widespread skin condition, which is considered a multifactorial disease influenced, in part, by Malassezia spp. opportunistic activities, as well as various endogenous and exogenous factors. Malassezia species are lipophilic, lipid-dependent yeasts that are members of the normal mycobiota of the human skin. Their isolation from SD lesions varies around the world and the study of the relationship among factors such as gender, age, immunosuppressive condition of the patient and SD development, can lead to a better understanding of this disease. To elucidate the association of age and gender with the development of SD and to precisely determine the Malassezia species involved in the disease, samples were obtained from 134 individuals, including individuals without lesions, human immunodeficiency virus positive patients, individuals with seborrheic dermatitis, and HIV patients with seborrheic dermatitis. Malassezia spp. were identified by phenotypic and genotypic methods and a phylogenetic analysis was performed using Bayesian inference. This study revealed that age and gender are not predisposing factors for SD development, and that the most frequent species of Malassezia related to SD development among the Colombian population is M. restricta. We also report the isolation of M. yamatoensis for the first time in Colombia, and propose an ITS2 secondary structure from Malassezia taxa that can be used for precise identification and to establish more robust phylogenetic relationships.

El sistema económico neoliberal ha obligado a los países en desarrollo a implementar reformas estructurales que condicionan el ejercicio de una de las principales obligaciones del Estado, la procuración del bienestar social a la población. La seguridad en el ámbito educativo, de salud, de vivienda, de trabajo, entre otros, se han visto afectados por estas reformas. El derecho a la salud, en este contexto, está condicionado más por factores asociados con intereses de sistemas financieros internacionales que por una perspectiva de derechos humanos. La respuesta que el Sistema de Salud en México brinda a las personas que viven con vihresulta insuficiente debido a las fallas en los programas de atención y prevención que generalmente operan con menos recursos de los que requieren.

Lejano parece el día, a inicios del siglo XX, en que Paul Ehrlich propuso el término de "balas mágicas" como compuestos con toxicidad selectiva capaces de actuar contra microorganismos responsables de infecciones, pero no contra las células eucarióticas del hospedero. Sin lugar a dudas, el hallazgo de la penicilina, la bala mágica por excelencia, es un hito que dio un giro en esencia, los microorganismos tienen mecanismos para hacerse "invisibles" a las balas mágicas o a la terapia utilizada para combatir las enfermedades infecciosas. Para muchos era evidente que el fin de las infecciones bacterianas estaba próximo, sin considerar otros elementos que también tienen un papel importante en la evolución y el desarrollo de la resistencia: la plasticidad de los microorganismos causantes de la infección, y la selección de cepas resistentes por el uso irracional de antibióticos.

Yeasts of the genus Malassezia form a normal component of skin flora, but are also associated with several dermatological disorders. Since 1996, the description of new species in this genus have led to new questions about their epidemiology and pathogenicity.Herein, the frequency of Malassezia species in individuals with pityriasis versicolor, atopic dermatitis, seborrhoeic dermatitis, seborrhoeic dermatitis was compared in HIV patients and healthy individuals. Three body sites were selected for examination--head, thorax, and upper and lower extremities.The 154 Malassezia species were isolated from 112 individuals and grouped as follows: 39 with seborrhoeic dermatitis (20 were HIV-positive patients), 18 with pityriasis versicolor, 18 with atopic dermatitis and 37 without dermatological leisions. HIV patient samples were examined microscopically, and specimens from both patients and healthy subjects were cultured on modified Dixon agar medium. Subsequently, isolates were identified by macroscopic, microscopic and physiological characteristics.The most commonly isolated species were Malassezia globosa (37.5%), M. sympodialis (31.3%) and M. furfur (31.3%). Malazzerzia globosa predominated in patients with pityriasis versicolor (67%) and in HIV-positive patients with seborrhoeic dermatitis (85%). In non-HIV patients with atopic dermatitis or seborrhoeic dermatitis, M. furfur and M. restricta were isolated in 72% and 26% of the cases, respectively.Several conclusions were evident. First, Malassezia species was present in subjects with and without dermatological pathologies. Second, the species frequency in the sampled population differed from frequencies reported from other geographic areas. Third, Malassezia globosa was involved at high frequency in patients with dermatological pathologies, suggesting a higher pathogenicity of this species. Additional studies on each species are recommended to clarify their pathogenic roles in association with HIV-positive and normal subjects.