The CgHaa1-dependent pathway mediates Candida glabrata response and tolerance to acetic acid thereby enhancing colonization of vaginal epithelium

To successfully colonize the vaginal tract Candida glabrata has to cope with various stresses including the presence of acetic acid at a low pH that is produced by the bacteria that co-colonize this niche. The genes/pathways involved in C. glabrata tolerance and response to acetic acid are largely unknown, although these are a highly interesting set of novel targets to control vaginal infections caused by this yeast. Saccharomyces cerevisae response and tolerance to acetic acid was found to be largely mediated by the ScHaa1 transcription factor [1,2,3]. In this work the involvement of CgHaa1 in C. glabrata tolerance and response to acetic acid is demonstrated. Elimination of CgHAA1 gene from C. glabrata genome dramatically increased susceptibility of this pathogenic yeast to acetic acid (30 mM at pH 4.0). Around 140 genes were found to be up-regulated, directly or indirectly, by CgHaa1 in response to acetic acid stress, based on results of a transcriptomic analysis. Functional clustering of the genes activated by CgHaa1 under acetic acid stress shows an enrichment of those involved in carbohydrate metabolism, transport, cell wall maintenance, regulation of internal pH and nucleic acid processing. At least five of the CgHaa1-regulated genes were found to increase C. glabrata tolerance to acetic acid including CgGAD1, encoding a glutamate decarboxylase; CgTPO2/3, encoding a drug efflux pump of the Major Facilitator Superfamily; CgYPS1, encoding a cell wall aspartyl protease; and CAGL0H04851 and CAGL0E03740, encoding two uncharacterized ORFs. Altogether our results are consistent with the concept that the CgHaa1- signalling pathway increases C. glabrata tolerance to acetic acid by reducing the internal accumulation of the acid and by up-regulating the activity of the plasma membrane proton pump H+-ATPase CgPma1, two essential features for a robust weak acid response. The role exerted by CgHaa1 in the ability of C. glabrata to colonize reconstituted vaginal human epithelium (RVHE) in the presence of acetic acid (30 mM at pH 4.0) was also investigated in this work. In the absence of acetic acid wild-type and DCgHaa1 mutant cells were able to colonize RVHE at a similar rate, however, in the presence of acetic acid colonization of the vaginal tissue was markedly reduced in the mutant background. The reduced colonizing capacity of DCgHaa1 mutant cells was correlated with a reduced expression of the adhesin-encoding genes EPA6, EPA7 and EPA1 and with a lower adhesiveness to the extracellular matrix proteins fibronectin and vitronectin

Overexpression of Adenosine A2A receptors in rats: effects on depression, locomotion, and anxiety

Copyright: © 2014 Coelho, Alves, Canas, Valadas, Shmidt, Batalha, Ferreira, Ribeiro, Bader, Cunha, do Couto and Lopes. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Adenosine A2A receptors (A2AR) are a sub-type of receptors enriched in basal ganglia, activated by the neuromodulator adenosine, which interact with dopamine D2 receptors. Although this reciprocal antagonistic interaction is well-established in motor function, the outcome in dopamine-related behaviors remains uncertain, in particular in depression and anxiety. We have demonstrated an upsurge of A2AR associated to aging and chronic stress. Furthermore, Alzheimer's disease patients present A2AR accumulation in cortical areas together with depressive signs. We now tested the impact of overexpressing A2AR in forebrain neurons on dopamine-related behavior, namely depression. Adult male rats overexpressing human A2AR under the control of CaMKII promoter [Tg(CaMKII-hA2AR)] and aged-matched wild-types (WT) of the same strain (Sprague-Dawley) were studied. The forced swimming test (FST), sucrose preference test (SPT), and the open-field test (OFT) were performed to evaluate behavioral despair, anhedonia, locomotion, and anxiety. Tg(CaMKII-hA2AR) animals spent more time floating and less time swimming in the FST and presented a decreased sucrose preference at 48 h in the SPT. They also covered higher distances in the OFT and spent more time in the central zone than the WT. The results indicate that Tg(CaMKII-hA2AR) rats exhibit depressive-like behavior, hyperlocomotion, and altered exploratory behavior. This A2AR overexpression may explain the depressive signs found in aging, chronic stress, and Alzheimer's disease.Joana E. Coelho, Vânia L. Batalha and Diana G. Ferreira were supported by a grant from Fundação para a Ciência e Tecnologia (FCT); Paula M. Canas and Rodrigo A. Cunha were supported by FCT (PTDC/SAU-NSC/122254/2010) and Defense Advanced Research Projects Agency (DARPA, grant 09-68-ESR- FP-010). Luísa V. Lopes is an Investigator FCT, funded by Fundação para a Ciência e Tecnologia (PTDC-099853/2009) and Bial.info:eu-repo/semantics/publishedVersio

The CgHaa1-regulon mediates response and tolerance to acetic acid stress in the human pathogen Candida glabrata

To thrive in the acidic vaginal tract C. glabrata has to cope with high concentrations of acetic acid. The mechanisms underlying C. glabrata tolerance to acetic acid at low pH remain largely uncharacterized. In this work it is demonstrated the essential role of the CgHaa1 transcription factor (encoded by ORF CAGL0L09339g) in the response and tolerance of C. glabrata to acetic acid. Transcriptomic analysis showed that CgHaa1 regulates, directly or indirectly, the expression of about 75% of the genes activated under acetic acid stress. CgHaa1-activated targets are involved in multiple physiological functions including membrane transport, metabolism of carbohydrates and amino acids, regulation of the activity of the plasma membrane H+-ATPase and adhesion. Under acetic acid stress CgHaa1 increased the activity and the expression of the CgPma1 proton pump and contributed to increased colonization of vaginal epithelial cells by C. glabrata. CgHAA1, CgTPO3 and CgHSP30, two identified CgHaa1-activated targets, are herein demonstrated to be determinants of C. glabrata tolerance to acetic acid. The protective effect of CgTpo3 and of CgHaa1 was linked to a role of these proteins in reducing the accumulation of acetic acid inside C. glabrata cells. In response to acetic acid stress, marked differences were found in the regulons controlled by CgHaa1 and by its S. cerevisiae ScHaa1 ortholog, demonstrating a clear divergent evolution of the two regulatory networks. The results gathered in this study significantly advance the understanding of the molecular mechanisms underlying the success of C. glabrata as a vaginal colonizer.Cristoph Schueller (University of Natural Resources and Life Sciences, Austria) and Ken Haynes (University of Exeter, UK) are acknowledged for sharing strains. Funding received by the Institute for Bioengineering and Biosciences from the Portuguese Foundation for Science and Technology (FCT) (UID/BIO/04565/2013) and from Programa Operacional Regional de Lisboa 2020 (project no. 007317)is acknowledged. FCT is also acknowledged for funding the Centre of Biological Engineering through contracts FCOMP-01-0124-FEDER020243 and PTDC/EBB-EBI/120495/2010. Science Foundation Ireland and the Wellcome Trust are acknowledged for funding G.B

Comparison of zinc oxide nanoparticle integration into non-woven fabrics using different functionalisation methods for prospective application as active facemasks

The development of advanced facemasks stands out as a paramount priority in enhancing healthcare preparedness. In this work, different polypropylene non-woven fabrics (NWF) were characterised regarding their structural, physicochemical and comfort-related properties. The selected NWF for the intermediate layer was functionalised with zinc oxide nanoparticles (ZnO NPs) 0.3 and 1.2wt% using three different methods: electrospinning, dip-pad-dry and exhaustion. After the confirmation of ZnO NP content and distribution within the textile fibres by morphological and chemical analysis, the samples were evaluated regarding their antimicrobial properties. The functionalised fabrics obtained via dip-pad-dry unveiled the most promising data, with 0.017 ± 0.013wt% ZnO NPs being mostly located at the fibre’s surface and capable of total eradication of Staphylococcus aureus and Escherichia coli colonies within the tested 24 h (ISO 22196 standard), as well as significantly contributing (**** p < 0.0001) to the growth inhibition of the bacteriophage MS2, a surrogate of the SARS-CoV-2 virus (ISO 18184 standard). A three-layered structure was assembled and thermoformed to obtain facemasks combining the previously chosen NWF, and its resulting antimicrobial capacity, filtration efficiency and breathability (NP EN ISO 149) were assessed. The developed three-layered and multiscaled fibrous structures with antimicrobial capacities hold immense potential as active individual protection facemasks.FCT -Fundação para a Ciência e a Tecnologia(LA/P/0029/2020)info:eu-repo/semantics/publishedVersio

Genetic adaptive mechanisms mediating response and tolerance to acetic acid stress in the human pathogen Candida glabrata: role of the CgHaa1-dependent signaling pathway

C. glabrata is a commensal found in the human genitourinary tract but under certain conditions this harmless colonization evolves to a mucosal infection and, in more serious cases, to disseminated mycosis. To thrive in the acidic vaginal tract C. glabrata has to cope with the presence of a competing commensal microbiota known to restrain the overgrowth of pathogens through the production of acetic and lactic acids, among other interference effects. The persistent emergence of C. glabrata strains resistant to currently used antifungals demands the implementation of novel therapeutic strategies based on non-conventional targets. Genes contributing to increase C. glabrata competitiveness in the vaginal tract by mediating tolerance to the organic acids found therein are a cohort of interesting and yet unexplored therapeutic targets. Tolerance mechanisms of C. glabrata to acetic acid at low pH are poorly studied but much knowledge was gathered in Saccharomyces cerevisiae (Mira et al 2010a; 2010b; 2011; 2010c). In particular, the central role of the ScHaa1 transcription factor in mediating S. cerevisiae tolerance to acetic acid stress was demonstrated (Mira et al 2010b; 2011; 2010c). In this work it is shown that CgHaa1, an orthologue of ScHaa1, controls an acetic acid-responsive system in C. glabrata. The mechanisms by which the CgHaa1 pathway mediate tolerance to acetic acid in C. glabrata were further dissected, exploring a transcriptomics approach, being of notice the involvement of this regulatory system in the control of internal pH and in reducing the internal accumulation of the acid. In the presence of acetic acid CgHaa1 enhanced adhesion and colonization of reconstituted vaginal human epithelium by C. glabrata, this correlating with a positive effect of CgHaa1 over the expression of adhesinencoding genes. The results obtained show similarities, but also remarkable differences, in the way by which the ScHaa1 and CgHaa1 pathways mediate tolerance to acetic acid in S. cerevisiae and in C. glabrata, indicating a functional expansion of the network in the later species. The role of the CgHaa1-pathway in the extreme acetic acid-tolerance exhibited by vaginal C. glabrata isolates will also be discussed, along with other uncovered mechanistic insights

A social and ecological assessment of tropical land uses at multiple scales: the Sustainable amazon network

Science has a critical role to play in guiding more sustainable development trajectories. Here, we present the Sustainable Amazon Network (Rede Amazônia Sustentável, RAS): a multidisciplinary research initiative involving more than 30 partner organizations working to assess both social and ecological dimensions of land-use sustainability in eastern Brazilian Amazonia. The research approach adopted by RAS offers three advantages for addressing land-use sustainability problems: (i) the collection of synchronized and co-located ecological and socioeconomic data across broad gradients of past and present human use; (ii) a nested sampling design to aid comparison of ecological and socioeconomic conditions associated with different land uses across local, landscape and regional scales; and (iii) a strong engagement with a wide variety of actors and non-research institutions. Here, we elaborate on these key features, and identify the ways in which RAS can help in highlighting those problems in most urgent need of attention, and in guiding improvements in land-use sustainability in Amazonia and elsewhere in the tropics. We also discuss some of the practical lessons, limitations and realities faced during the development of the RAS initiative so far

Perspectives on utilization of edible coatings and nano-laminate coatings for extension of postharvest storage of fruits and vegetables

It is known that in developing countries, a large quantity of fruit and vegetable losses results at postharvest and processing stages due to poor or scarce storage technology and mishandling during harvest. The use of new and innovative technologies for reducing postharvest losses is a requirement that has not been fully covered. The use of edible coatings (mainly based on biopolymers) as a postharvest technique for agricultural commodities has offered biodegradable alternatives in order to solve problems (e.g., microbiological growth) during produce storage. However, biopolymer-based coatings can present some disadvantages such as: poor mechanical properties (e.g., lipids) or poor water vapor barrier properties (e.g., polysaccharides), thus requiring the development of new alternatives to solve these drawbacks. Recently, nanotechnology has emerged as a promising tool in the food processing industry, providing new insights about postharvest technologies on produce storage. Nanotechnological approaches can contribute through the design of functional packing materials with lower amounts of bioactive ingredients, better gas and mechanical properties and with reduced impact on the sensorial qualities of the fruits and vegetables. This work reviews some of the main factors involved in postharvest losses and new technologies for extension of postharvest storage of fruits and vegetables, focused on perspective uses of edible coatings and nano-laminate coatings.María L. Flores-López thanks Mexican Science and Technology Council (CONACYT, Mexico) for PhD fellowship support (CONACYT Grant Number: 215499/310847). Miguel A. Cerqueira (SFRH/BPD/72753/2010) is recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, POPH-QREN and FSE Portugal). The authors also thank the FCT Strategic Project of UID/ BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project ‘‘BioInd Biotechnology and Bioengineering for improved Industrial and AgroFood processes,’’ REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico – FUNCAP, CE Brazil (CI10080-00055.01.00/13)

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic