Antimicrobial effect of farnesol, a Candida albicans quorum sensing molecule, on Paracoccidioides brasiliensis growth and morphogenesis

<p>Abstract</p> <p>Background</p> <p>Farnesol is a sesquiterpene alcohol produced by many organisms, and also found in several essential oils. Its role as a quorum sensing molecule and as a virulence factor of <it>Candida albicans </it>has been well described. Studies revealed that farnesol affect the growth of a number of bacteria and fungi, pointing to a potential role as an antimicrobial agent.</p> <p>Methods</p> <p>Growth assays of <it>Paracoccidioides brasiliensis </it>cells incubated in the presence of different concentrations of farnesol were performed by measuring the optical density of the cultures. The viability of fungal cells was determined by MTT assay and by counting the colony forming units, after each farnesol treatment. The effects of farnesol on <it>P. brasiliensis </it>dimorphism were also evaluated by optical microscopy. The ultrastructural morphology of farnesol-treated <it>P. brasiliensis </it>yeast cells was evaluated by transmission and scanning electron microscopy.</p> <p>Results</p> <p>In this study, the effects of farnesol on <it>Paracoccidioides brasiliensis </it>growth and dimorphism were described. Concentrations of this isoprenoid ranging from 25 to 300 μM strongly inhibited <it>P. brasiliensis </it>growth. We have estimated that the MIC of farnesol for <it>P. brasiliensis </it>is 25 μM, while the MLC is around 30 μM. When employing levels which don't compromise cell viability (5 to 15 μM), it was shown that farnesol also affected the morphogenesis of this fungus. We observed about 60% of inhibition in hyphal development following <it>P. brasiliensis </it>yeast cells treatment with 15 μM of farnesol for 48 h. At these farnesol concentrations we also observed a significant hyphal shortening. Electron microscopy experiments showed that, despite of a remaining intact cell wall, <it>P. brasiliensis </it>cells treated with farnesol concentrations above 25 μM exhibited a fully cytoplasmic degeneration.</p> <p>Conclusion</p> <p>Our data indicate that farnesol acts as a potent antimicrobial agent against <it>P. brasiliensis</it>. The fungicide activity of farnesol against this pathogen is probably associated to cytoplasmic degeneration. In concentrations that do not affect fungal viability, farnesol retards the germ-tube formation of <it>P. brasiliensis</it>, suggesting that the morphogenesis of this fungal is controlled by environmental conditions.</p

“Las penas con pan duelen menos”: The role of food and culture in Latinas with disordered eating behaviors

This study elucidated the experiences of eighteen Latina adults (mean age = 38.5 years) from “Promoviendo una Alimentación Saludable” Project who received nutritional intervention as part of the clinical trial. Half of the participants were first generation immigrants from Mexico (50%), followed by U.S. born with 16.7%. Remaining nationalities represented were Bolivia, Colombia, Guatemala, Honduras, Peru, and Venezuela with 33.3% combined. The average duration of living in the U.S. was 11.1 years. The mean body mass index (BMI) at baseline was 36.59 kg/m2 (SD=7.72). Based on the DSM-IV, 28% (n=5) participants were diagnosed with binge-eating disorder, 33% (n=6) with bulimia nervosa purging type and 39% (n=7) with eating disorder not otherwise specified. Participants received up to three nutritional sessions; a bilingual dietitian conducted 97.8% of sessions in Spanish. In total, fifty nutritional sessions were included in the qualitative analysis. A three step qualitative analysis was conducted. First, a bilingual research team documented each topic discussed by patients and all interventions conducted by the dietitian. Second, all topics were classified into specific categories and the frequency was documented. Third, a consensus with the dietitian was performed to validate the categories identified by the research team. Six categories (describing eating patterns, emotional distress, Latino culture values, family conflicts associated with disturbed eating behaviors, lack of knowledge of healthy eating, and treatment progress) emerged from patients across all nutritional sessions. Considering the background of immigration and trauma (60%, n=15) in this sample; the appropriate steps of nutritional intervention appear to be: 1) elucidating the connection between food and emotional distress, 2) providing psychoeducation of healthy eating patterns using the plate method, and 3) developing a meal plan

Integration of genetic, genomic and transcriptomic information identifies putative regulators of adventitious root formation in Populus

Clustering the difference in transcriptome response of PtQTL and PdQTL genotypes. Modulated Modularity Clustering of genes displaying a similar pattern of expression differences between genotypes from the PtQTL and PdQTL categories, at all time points. (DOCX 25 kb

Bee Pollination Highly Improves Oil Quality in Sunflower

Sunflower is a pollinator-dependent crop and one of the most cultivated oilseeds in the world, supporting important sectors of the agricultural industry, such as the food supply, because it is an important source of vitamin E and unsaturated fatty acids for human health. Although it is well stablished that bee pollination improves sunflower seed set, it is still unknown if pollinators influence the nutritional composition. Considering the economic importance of sunflowers for several Brazilian agricultural sectors, the aim of this study was to evaluate the effect of the bee community for (1) achene quality (weight and nutritional composition) and (2) market value. Exclusion experiments were performed with hybrid sunflowers and showed that bee pollination enhanced the achene weight by 91 %, the levels of vitamin E by 45 % and unsaturated fatty acids by 0.3 %. Also, it was estimated that due to the pollination services provided by bees, the grower of the sunflower cultivar used in this study nearly duplicates the sale value of the achenes per hectare of cultivated area. Thus, the current study highlights the importance of bees as providers of cross- and self-pollination to nutritional quality of sunflower achenes and provides useful baseline figures to further evaluations of the effects of pollinators on human diets and health

Genomic analysis and immune response in a murine mastitis model of vB_EcoM-UFV13, a potential biocontrol agent for use in dairy cows

Bovine mastitis remains the main cause of economic losses for dairy farmers. Mammary pathogenic Escherichia coli (MPEC) is related to an acute mastitis and its treatment is still based on the use of antibiotics. In the era of antimicrobial resistance (AMR), bacterial viruses (bacteriophages) present as an efficient treatment or prophylactic option. However, this makes it essential that its genetic structure, stability and interaction with the host immune system be thoroughly characterized. The present study analyzed a novel, broad host-range anti-mastitis agent, the T4virus vB-EcoM-UFV13 in genomic terms, and its activity against a MPEC strain in an experimental E. coli-induced mastitis mouse model. 4,975 Single Nucleotide Polymorphisms (SNPs) were assigned between vB-EcoM-UFV13 and E. coli phage T4 genomes with high impact on coding sequences (CDS) (37.60%) for virion proteins. Phylogenetic trees and genome analysis supported a recent infection mix between vB-EcoM-UFV13 and Shigella phage Shfl2. After a viral stability evaluation (e.g pH and temperature), intramammary administration (MOI 10) resulted in a 10-fold reduction in bacterial load. Furthermore, pro-inflammatory cytokines, such as IL-6 and TNF-\u3b1, were observed after viral treatment. This work brings the whole characterization and immune response to vB-EcoM-UFV13, a biocontrol candidate for bovine mastitis

Avian haemosporidians in the cattle egret (Bubulcus ibis) from central-western and southern Africa: high diversity and prevalence

We described the geographic distribution of 82 haemosporidian lineages (Plasmodium, Haemoproteus, and Leucocytozoon) in the cattle egret sampled in five countries in central-western and southern Africa. Seventy-three lineages have not previously been reported. We determined the prevalence of three haemosporidians in the samples. We investigated the influence of the internal environment of the host and environmental variables on the Plasmodium diversity and whether environmental variables may explain spatial variations in the prevalence of Plasmodium. We screened DNA from 509 blood samples from nestlings in 15 African colonies for infection by sequencing the cytochrome b gene of parasites. The molecular phylogenetic analysis was performed using Bayesian methods and including sequences from the MalAvi and GeneBank databases. We found 62 new Plasmodium lineages in a clade with MYCAME02, which is a lineage described in waterbirds and recently identified in birds of prey as Plasmodium paranucleophilum. Two Haemoproteus lineages identified in cattle egret formed a distinct group with Haemoproteus catharti and MYCAMH1 (Haemoproteus spp.). Seven Leucocytozoon lineages found in the cattle egret clustered with Leucocytozoon californicus. We found different Plasmodium diversities among the colonies sampled, demonstrating that the internal environment of the host is not the primary determinant of diversity. A linear mixed-effects multivariate model showed that precipitation was positively associated with Plasmodium diversity when controlling for the effects of temperature, colony composition (mixed and non-mixed species) and country. Moreover, a generalized mixed model showed that temperature was positively associated with the prevalence of Plasmodium when controlling for precipitation, elevation and country. We conclude that the cattle egret is a good model for future haemosporidian studies, as we found a significant number of new lineages in this host, which occupies regions with different climate characteristics where environmental variables exert an influence on the diversity and prevalence of Plasmodium

Phylogenetic and functional diversity of metagenomic libraries of phenol degrading sludge from petroleum refinery wastewater treatment system

In petrochemical refinery wastewater treatment plants (WWTP), different concentrations of pollutant compounds are received daily in the influent stream, including significant amounts of phenolic compounds, creating propitious conditions for the development of particular microorganisms that can rapidly adapt to such environment. In the present work, the microbial sludge from a refinery WWTP was enriched for phenol, cloned into fosmid vectors and pyrosequenced. The fosmid libraries yielded 13,200 clones and a comprehensive bioinformatic analysis of the sequence data set revealed a complex and diverse bacterial community in the phenol degrading sludge. The phylogenetic analyses using MEGAN in combination with RDP classifier showed a massive predominance of Proteobacteria, represented mostly by the genera Diaphorobacter, Pseudomonas, Thauera and Comamonas. The functional classification of phenol degrading sludge sequence data set generated by MG-RAST showed the wide metabolic diversity of the microbial sludge, with a high percentage of genes involved in the aerobic and anaerobic degradation of phenol and derivatives. In addition, genes related to the metabolism of many other organic and xenobiotic compounds, such as toluene, biphenyl, naphthalene and benzoate, were found. Results gathered herein demonstrated that the phenol degrading sludge has complex phylogenetic and functional diversities, showing the potential of such community to degrade several pollutant compounds. This microbiota is likely to represent a rich resource of versatile and unknown enzymes which may be exploited for biotechnological processes such as bioremediation

The Floristic-Holistic Method for Arid, Semiarid, and Subhumid Areas: A Tool for the Revaluation of Floristic Diversity, Conservation, and Protection of the Ecosystem

The valorization of methods for comprehensive data collection is one of the fundamental tools to establish concrete bases and is applicable to lines of work in conservation, preservation, and protection of ecosystems. During the last 20 years, from the Botany Laboratory and Herbarium Trelew, we have valued the Floristic-Holistic Method that we have been adapting, for flora surveys. Method is intensively used in some Argentine provinces of arid, semiarid, and subhumid zones of the South American Arid Diagonal (Santa Cruz, Chubut, Río Negro, Neuquén, Mendoza, and arid islands of the Patagonian Atlantic coast). This revaluation focuses its importance on not only providing information on ecological parameters (bare soil, topsoil, living plant cover, and dead plant cover), richness, equitability, and floristic diversity, but also on status, conservation, botanical types, biological forms, adaptations, plant density, percentages of protected species, potential invasions of exotic species, forage productivity, and animal receptivity. The information is comprehensive and adaptable to different situations, applicable to different plant associations, types of terrain, and landscape units (open and closed mount, shrubby steppes, subshrubs, grasses, wastelands, rocky fields, peladales, and all kinds of modified areas). The method thus holistically conceptualizes ecosystem goods and services, allowing their study at different scales

GEOS-5 Aerosol Modeling Data Assimilation: Update on Recent and Future Development

No abstract availabl

Evaluation of MCM-2 Expression in TMA Cervical Specimens

Background:Minichromosome maintenance proteins (MCM) are highly expressed in actively replicating cells. The need for biological markers for cervical carcinoma and its precursor lesions is emerging. Our main aim was to determine the immunohistochemical expression of MCM-2 in HIV-positive and -negative dysplastic cervical specimens. Methods:Immunohistochemical analysis of MCM-2 was performed in a total of 352 cervical TMA specimens of normal control, low-grade CIN, high-grade CIN and invasive tumor. 38 specimens were from HIV-positive women. A receiver operating characteristic (ROC) curve was constructed to determine the best cutoff to diagnose high-grade CIN and invasive cervical cancer. Results:In the progression from normal epithelium to high-grade CIN and invasive tumor we found significant differences in the MCM-2 expression (p,0.05). Based on the ROC curve of 80% with an area under the curve (AUC) of 0.78, expression of MCM-2 to diagnose high-grade CIN and invasive tumor resulted in sensitivity of 81%, specificity of 66%, a positive predictive value (PPV) of 86% and a negative predictive value (NPV) of 57%. HIV-positive cervices revealed a decreasing expression of MCM-2 in both LGCIN and HGCIN compared with HIV-negative specimens (p,0.0001). Conclusions:The present study suggests that immunohistochemical MCM-2 may not be a promising biomarker for diagnosing high-grade CIN and invasive cance