Diazoxon exposure increases susceptibility to infection by Salmonella Typhimurium.

Various exogenous factors, such as microbiological and chemical contamination condition food security. Salmonella Typhimurium (S. Typhimurium) is the cause of salmonellosis. This bacterium utilizes phagocytosis to create bacterial reservoirs. On the other hand, exposure to chemical contaminants, such as pesticides, increases susceptibility to numerous infections. Therefore, this research aims to evaluate the effect of co-exposure to diazoxon and S. Typhimurium on the in vitro infection dynamics. For this purpose, human mononuclear cells were pre-exposed in vitro to diazoxon and then challenged with S. Typhimurium at 1, 8, and 24 h. Bacterial internalization, actin polymerization, and reactive oxygen species (ROS) were analyzed. Obtained data show that mononuclear cells previously exposed to diazoxon exhibit greater internalization of S. Typhimurium. Likewise, greater ROS production and an increase in actin polymerization were observed. Therefore, in the proposed scenario, obtained data suggest that co-exposure to diazoxon and S. Typhimurium increases susceptibility to acquiring an illness.

Etiología de baja visión y ceguera en siete centros de referencia en Colombia entre los años 2012 a 2017 / Etiology of low vision and blindness in seven reference centers in Colombia between the years 2012 to 2017

Introducción: La baja visión y la ceguera tienen alta prevalencia mundial, siendo categorías de discapacidad frecuentes en Colombia. Se requieren estudios que caractericen la etiología de las deficiencias visuales permanentes. Objetivo: Identificar y caracterizar las diferentes causas de baja visión y ceguera en siete centros de referencia para la población con discapacidad visual en Colombia, atendida entre los años 2012 a 2017 en seis ciudades capitales. Materiales y métodos:Estudio retrospectivo, serie de casos, descriptivo y multicéntrico.Resultados: Se contó con una muestra de 879 registros de pacientes con discapacidad visual. El 70% (612/879) con baja visión y 30% (267/879) con ceguera. Para todos los grupos de edad es más prevalente la baja visión. La etiología más frecuente en pacientes con baja visión fue la degeneración macular asociada a la edad (DMAE) (24%, 144/612); en pacientes con ceguera fue el glaucoma (17%, 45/267). Discusión: Posiblemente en Colombia las causas de baja visión y ceguera van más allá de las cataratas, errores de refracción no corregidos y ceguera infecciosa. Discusión: Las etiologías más frecuentes encontradas son condiciones oculares crónicas y diversas, que requieren intervenciones específicas para disminuir su prevalencia y prevenir casos de baja visión y ceguera.

Introduction: Low vision and blindness have high global prevalence, with categories of disability common in Colombia. Studies that characterize the etiology of permanent visual impairments are required. Objective:To identify and characterize the different causes of low vision and blindness in seven reference centers for the visually impaired population in Colombia, attended between 2012 and 2017 in six capital cities. Materials and Methods:Retrospective, case series, descriptive and multicenter study. Results: A sample of 879 records of visually impaired patients was available. Low vision is more prevalent for all age groups. 70% (612/879) low vision and 30% (267/879) blindness. The most common etiology in patients with low vision was age-related macular degeneration (DMAE) (24%, 144/612); in patients with blindness it was glaucoma (17%, 45/267). Discussions: Possibly in Colombia the causes of low vision and blindness go beyond cataracts, un corrected refractive errors and infectious blindness. Conclusions: The most common etiologies found are chronic and diverse eye conditions, which require specific interventions to decrease their prevalence and prevent cases of low vision and blindness.

Introdução: Baixa visão e cegueira têm alta prevalência global, com categorias de incapacidade comuns na Colômbia. São necessários estudos que caracterizem a etiologia das deficiências visuais permanentes. Objetivo: Identificar e caracterizar as diferentes causas de baixa visão e cegueira em sete centros de referência para a população deficiente visual na Colômbia, atendidos entre 2012 e 2017 em seis capitais. Materiais e Métodos: Estudo retrospectivo, série de casos, descritivo e multicêntrico. Resultados: Uma amostra de 879 registros de pacientes com deficiência visual estava disponível. 54% (478/879) homens. A baixa visão é mais prevalente para todas as faixas etárias. 70% (612/879) baixa visão e 30% (267/879) cegueira. A etiologia mais comum em pacientes com baixa visão foi a degeneração macular relacionada à idade (DMAE) (24%, 144/612); em pacientes com cegueira foi glaucoma (17%, 45/267).Discussão: Possivelmente na Colômbia as causas da baixa visão e cegueira vão além da catarata, erros refrativos não corrigidos e cegueira infecciosa. Conclusões: As etiologias mais comuns encontradas são condições oculares crônicas e diversas, que requerem intervenções específicas para diminuir sua prevalência e prevenir casos de baixa visão e cegueira

Microbial Community and Biochemical Dynamics of Biological Soil Crusts across a Gradient of Surface Coverage in the Central Mojave Desert.

In this study, we expand upon the biogeography of biological soil crusts (BSCs) and provide molecular insights into the microbial community and biochemical dynamics along the vertical BSC column structure, and across a transect of increasing BSC surface coverage in the central Mojave Desert, CA, United States. Next generation sequencing reveals a bacterial community profile that is distinct among BSCs in the southwestern United States. Distribution of major phyla in the BSC topsoils included Cyanobacteria (33 ± 8%), Proteobacteria (26 ± 6%), and Chloroflexi (12 ± 4%), with Phormidium being the numerically dominant genus. Furthermore, BSC subsurfaces contained Proteobacteria (23 ± 5%), Actinobacteria (20 ± 5%), and Chloroflexi (18 ± 3%), with an unidentified genus from Chloroflexi (AKIW781, order) being numerically dominant. Across the transect, changes in distribution at the phylum (p < 0.0439) and genus (p < 0.006) levels, including multiple biochemical and geochemical trends (p < 0.05), positively correlated with increasing BSC surface coverage. This included increases in (a) Chloroflexi abundance, (b) abundance and diversity of Cyanobacteria, (b) OTU-level diversity in the topsoil, (c) OTU-level differentiation between the topsoil and subsurface, (d) intracellular ATP abundances and catalase activities, and (e) enrichments in clay, silt, and varying elements, including S, Mn, Co, As, and Pb, in the BSC topsoils. In sum, these studies suggest that BSCs from regions of differing surface coverage represent early successional stages, which exhibit increasing bacterial diversity, metabolic activities, and capacity to restructure the soil. Further, these trends suggest that BSC successional maturation and colonization across the transect are inhibited by metals/metalloids such as B, Ca, Ti, Mn, Co, Ni, Mo, and Pb.

International Space Station environmental microbiome - microbial inventories of ISS filter debris.

Despite an expanding array of molecular approaches for detecting microorganisms in a given sample, rapid and robust means of assessing the differential viability of the microbial cells, as a function of phylogenetic lineage, remain elusive. A propidium monoazide (PMA) treatment coupled with downstream quantitative polymerase chain reaction (qPCR) and pyrosequencing analyses was carried out to better understand the frequency, diversity, and distribution of viable microorganisms associated with debris collected from the crew quarters of the International Space Station (ISS). The cultured bacterial counts were more in the ISS samples than cultured fungal population. The rapid molecular analyses targeted to estimate viable population exhibited 5-fold increase in bacterial (qPCR-PMA assay) and 25-fold increase in microbial (adenosine triphosphate assay) burden than the cultured bacterial population. The ribosomal nucleic acid-based identification of cultivated strains revealed the presence of only four to eight bacterial species in the ISS samples, however, the viable bacterial diversity detected by the PMA-pyrosequencing method was far more diverse (12 to 23 bacterial taxa) with the majority consisting of members of actinobacterial genera (Propionibacterium, Corynebacterium) and Staphylococcus. Sample fractions not treated with PMA (inclusive of both live and dead cells) yielded a great abundance of highly diverse bacterial (94 to 118 taxa) and fungal lineages (41 taxa). Even though deep sequencing capability of the molecular analysis widened the understanding about the microbial diversity, the cultivation assay also proved to be essential since some of the spore-forming microorganisms were detected only by the culture-based method. Presented here are the findings of the first comprehensive effort to assess the viability of microbial cells associated with ISS surfaces, and correlate differential viability with phylogenetic affiliation.

Description of Tersicoccus phoenicis gen. nov., sp. nov. isolated from spacecraft assembly clean room environments.

Two strains of aerobic, non-motile, Gram-reaction-positive cocci were independently isolated from geographically distinct spacecraft assembly clean room facilities (Kennedy Space Center, Florida, USA and Centre Spatial Guyanais, Kourou, French Guiana). A polyphasic study was carried out to delineate the taxonomic identity of these two isolates (1P05MA(T) and KO_PS43). The 16S rRNA gene sequences exhibited a high similarity when compared to each other (100 %) and lower than 96.7 % relatedness with Arthrobacter crystallopoietes ATCC 15481(T), Arthrobacter luteolus ATCC BAA-272(T), Arthrobacter tumbae DSM 16406(T) and Arthrobacter subterraneus DSM 17585(T). In contrast with previously described Arthrobacter species, the novel isolates maintained their coccidal morphology throughout their growth and did not exhibit the rod-coccus life cycle typically observed in nearly all Arthrobacter species, except A. agilis. The distinct taxonomic identity of the novel isolates was confirmed based on their unique cell-wall peptidoglycan type (A.11.20; Lys-Ser-Ala2) and polar lipid profile (presence of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, an unknown phospholipid and two unknown glycolipids). The G+C content of the genomic DNA was 70.6 mol%. The novel strains revealed MK-9(H2) and MK-8(H2) as dominant menaquinones and exhibited fatty acid profiles consisting of major amounts of anteiso-C15 : 0 and anteiso-C17 : 0 and moderate amounts of iso-C15 : 0 discriminating them again from closely related Arthrobacter species. Based on these observations, the authors propose that strains 1P05MA(T) and KO_PS43 be assigned into a separate genus Tersicoccus gen. nov. For this new taxon, comprising strains 1P05MA(T) and KO_PS43, we propose the name Tersicoccus phoenicis gen. nov., sp. nov. (the type species of Tersicoccus), represented by the type strain Tersicoccus phoenicis 1P05MA(T) ( = NRRL B-59547(T) = DSM 30849(T)).