Complex and Controversial Roles of Eicosanoids in Fungal Pathogenesis

The prevalence of fungal infections has increased in immunocompromised patients, leading to millions of deaths annually. Arachidonic acid (AA) metabolites, such as eicosanoids, play important roles in regulating innate and adaptative immune function, particularly since they can function as virulence factors enhancing fungal colonization and are produced by mammalian and lower eukaryotes, such as yeasts and other fungi (Candida albicans, Histoplasma capsulatum and Cryptococcus neoformans). C. albicans produces prostaglandins (PG), Leukotrienes (LT) and Resolvins (Rvs), whereas the first two have been well documented in Cryptococcus sp. and H. capsulatum. In this review, we cover the eicosanoids produced by the host and fungi during fungal infections. These fungal-derived PGs have immunomodulatory functions analogous to their mammalian counterparts. Prostaglandin E2 (PGE2) protects C. albicans and C. parapsilosis cells from the phagocytic and killing activity of macrophages. H. capsulatum PGs augment the fungal burden and host mortality rates in histoplasmosis. However, PGD2 potentiates the effects and production of LTB4, which is a very potent neutrophil chemoattractant that enhances host responses. Altogether, these data suggest that eicosanoids, mainly PGE2, may serve as a new potential target to combat diverse fungal infections

Lipid droplet levels vary heterogeneously in response to simulated gastrointestinal stresses in different probiotic Saccharomyces cerevisiae strains

AbstractTo exert their therapeutic action, probiotic Saccharomyces cerevisiae strains must survive harsh digestive environments. Lipid droplets accumulate in cells which undergo stress-inducing situations, supposedly having a protective role. We assessed lipid droplet levels, either naturally accumulated or induced in response to digestive challenges, of probiotic strains S. boulardii, S. cerevisiae A-905, S. cerevisiae Sc47 and S. cerevisiae L11, and of non-probiotic strains S. cerevisiae BY4741 and S. cerevisiae BY4743. Strains 905 and Sc47 had lower and higher lipid droplet levels, respectively, when compared to the remaining strains, showing that higher accumulationof these neutral lipids is not a feature shared by all probiotic Saccharomyces strains. When submitted to simulated gastric or bile salts environments, lipid droplet levels increase in all tested probiotic strains, at least for one to the induced stresses, suggesting that lipid droplets participate in the protective mechanisms against gastrointestinal stresses in probiotic Saccharomyces yeasts

Real time Quantum state holography using coherent transients

In a two level atom, real-time quantum state holography is performed through interferences between quantum states created by a reference pulse and a chirped pulse resulting in coherent transients. A sequence of several measurements allows one to measure the real and imaginary parts of the excited state wave function. These measurements are performed during the interaction with the ultrashort laser pulse. The extreme sensitivity of this method to the pulse shape provides a tool for electric field measurement

Group V secretory phospholipase A2 is involved in tubular integrity and sodium handling in the kidney

Group V (GV) phospholipase A2 (PLA2) is a member of the family of secreted PLA2 (sPLA2) enzymes. This enzyme has been identified in several organs, including the kidney. However, the physiologic role of GV sPLA2 in the maintenance of renal function remains unclear. We used mice lacking the gene encoding GV sPLA2 (Pla2g5−/−) and wild-type breeding pairs in the experiments. Mice were individually housed in metabolic cages and 48-h urine was collected for biochemical assays. Kidney samples were evaluated for glomerular morphology, renal fibrosis, and expression/activity of the (Na+ + K+)-ATPase α1 subunit. We observed that plasma creatinine levels were increased in Pla2g5−/− mice following by a decrease in creatinine clearance. The levels of urinary protein were higher in Pla2g5−/− mice than in the control group. Markers of tubular integrity and function such as γ-glutamyl transpeptidase, lactate dehydrogenase, and sodium excretion fraction (FENa+) were also increased in Pla2g5−/− mice. The increased FENa+ observed in Pla2g5−/− mice was correlated to alterations in cortical (Na+ + K+) ATPase activity/ expression. In addition, the kidney from Pla2g5−/− mice showed accumulation of matrix in corticomedullary glomeruli and tubulointerstitial fibrosis. These data suggest GV sPLA2 is involved in the maintenance of tubular cell function and integrity, promoting sodium retention through increased cortical (Na+ + K+)-ATPase expression and activity

O clickbait no ciberjornalismo português e brasileiro: o caso português

A investigação que aqui se apresenta partiu da proposta de analisar a incidência de clickbait no ciberjornalismo português e brasileiro. Faz parte de um projeto desenvolvido em conjunto por investigadores brasileiros e portugueses, em que cada grupo efetuou a verificação em 18 cibermeios de informação geral do seu país com abrangência nacional e com produção própria e atualizada frequentemente, tanto nas páginas Web como no Facebook. Neste artigo apresentamos os resultados encontrados nos 270 títulos/conteúdos que constituíram a amostra portuguesa, que apontam para um índice de clickbait de 39,6%. Analisando individualmente os 32 indicadores, verificamos que nenhum chega aos 10%, destacando-se como valor mais alto a "Informação empolada", presente em 8,5% da amostra.The paper aims to analyze the incidence of clickbait in Portuguese and Brazilian online journalism. It is part of an activity carried out jointly by Brazilian and Portuguese researchers, in which each group carried out the verification in the Web and Facebook pages of 18 general information vehicles of such countries, each having national coverage, as well as its own production and frequent updates. This article presents the results found in the Portuguese sample that shows a high clickbait index, of 39,6%, when cross-checking the general data. On the other hand, the values are reduced when we look at the 32 indicators individually, all of them with rates below 10%

O clickbait no ciberjornalismo português e brasileiro: o caso brasileiro

O trabalho tem como proposta analisar a incidência de "clickbait" no jornalismo online português e brasileiro. Faz parte de uma atividade realizada em conjunto por pesquisadores brasileiros e portugueses, em que cada grupo efetuou a verificação em 18 veículos de informação geral do seu país com abrangência nacional, com produção própria e atualizada frequentemente, tanto nas páginas Web, assim como no Facebook. Este artigo traz os resultados encontrados na amostra brasileira que apontam um alto índice de "clickbait" ao se verificar os dados gerais, com 54,4% da amostra com ocorrência desta prática. Ao mesmo tempo, os valores se reduzem ao olharmos os 32 indicadores individualmente, em que apenas três tiveram índices superiores a 10%.The paper aims to analyze the incidence of clickbait in Portuguese and Brazilian online journalism. It is part of an activity carried out jointly by Brazilian and Portuguese researchers, in which each group carried out the verification in the Web and Facebook pages of 18 general information vehicles of such countries, each having national coverage, as well as its own production and frequent updates. This article presents the results found in the Brazilian sample that shows a high clickbait index, of 54.4%, when crosschecking the general data. On the other hand, the values are reduced when we look at the 32 indicators individually, in which only three had rates above 10%

Complex and Controversial Roles of Eicosanoids in Fungal Pathogenesis

The prevalence of fungal infections has increased in immunocompromised patients, leading to millions of deaths annually. Arachidonic acid (AA) metabolites, such as eicosanoids, play important roles in regulating innate and adaptative immune function, particularly since they can function as virulence factors enhancing fungal colonization and are produced by mammalian and lower eukaryotes, such as yeasts and other fungi (Candida albicans, Histoplasma capsulatum and Cryptococcus neoformans). C. albicans produces prostaglandins (PG), Leukotrienes (LT) and Resolvins (Rvs), whereas the first two have been well documented in Cryptococcus sp. and H. capsulatum. In this review, we cover the eicosanoids produced by the host and fungi during fungal infections. These fungal-derived PGs have immunomodulatory functions analogous to their mammalian counterparts. Prostaglandin E2 (PGE2) protects C. albicans and C. parapsilosis cells from the phagocytic and killing activity of macrophages. H. capsulatum PGs augment the fungal burden and host mortality rates in histoplasmosis. However, PGD2 potentiates the effects and production of LTB4, which is a very potent neutrophil chemoattractant that enhances host responses. Altogether, these data suggest that eicosanoids, mainly PGE2, may serve as a new potential target to combat diverse fungal infections

Fungal Melanin and the Mammalian Immune System

Melanins are ubiquitous complex polymers that are commonly known in humans to cause pigmentation of our skin. Melanins are also present in bacteria, fungi, and helminths. In this review, we will describe the diverse interactions of fungal melanin with the mammalian immune system. We will particularly focus on Cryptococcus neoformans and also discuss other major melanotic pathogenic fungi. Melanin interacts with the immune system through diverse pathways, reducing the effectiveness of phagocytic cells, binding effector molecules and antifungals, and modifying complement and antibody responses