Synthesis and characterization of dicarboxymethyl cellulose

Associate Laboratory for Green Chemistry-LAQV which is financed by national funds from FCT/MCTES (UID/QUI/50006/2019). FCT, Portugal (ROTEIRO/0031/2013–PINFRA/22161/2016, co-financed by FEDER through COMPETE 2020, POCI, and PORL and FCT through PIDDAC).Synthesis of dicarboxymethyl cellulose (DCMC) under heterogeneous conditions was examined. Cellulose was etherified using sodium bromomalonate in isopropanol/water in the presence of NaOH. The reaction was performed with five different NaOH concentrations (5–30 w/v %) and the products were characterized by anion-exchange high-performance liquid chromatography (AE-HPLC), inductively coupled plasma atomic emission- (ICP-AES), Fourier transform infrared- (FTIR), and nuclear magnetic resonance (1D-/2D-NMR) spectroscopy. Adjusting the amount of NaOH resulted in increasing functionalization of the cellulose achieving an average degree of substitution (DS) between 0.05 and 0.51. Both ICP-AES and AE-HPLC gave comparable DS values. NMR spectroscopic analysis showed that etherification occurred preferably at O-6 and, to a certain extent, at the secondary positions depending on the reaction conditions. Graphic abstract: [Figure not available: see fulltext.].authorsversionpublishe

Fusion proteins towards fungi and bacteria in plant protection

Research ArticleIn agriculture, although fungi are considered the foremost problem, infections by bacteria also cause significant economical losses. The presence of different diseases in crops often leads to a misuse of the proper therapeutic, or the combination of different diseases forces the use of more than one pesticide. This work concerns the development of a ‘super-Blad’: a chimeric protein consisting of Blad polypeptide, the active ingredient of a biological fungicide already on the market, and two selected peptides, SP10-5 and Sub5, proven to possess biological potential as antibacterial agents. The resulting chimeric protein obtained from the fusion of Blad with SP10-5 not only maintained strong antibacterial activity, especially against Xanthomonas spp. and Pseudomonas syringae, but was also able to retain the ability to inhibit the growth of both yeast and filamentous fungi. However, the antibacterial activity of Sub5 was considerably diminished when fused with Blad, which seems to indicate that not all fusion proteins behave equally. These newly designed drugs can be considered promising compounds for use in plant protection. A deeper and focused development of an appropriate formulation may result in a potent biopesticide that can replace, per se, two conventional chemistries with less impact on the environmentinfo:eu-repo/semantics/publishedVersio

Suspended-core fibers for sensing applications

A brief review on suspended-core fibers for sensing applications is presented. A historical overview over the previous ten years about this special designed microstructure optical fiber is described. This fiber presents attractive optical properties for chemical/biological or gas measurement, but it can be further explored for alternative sensing solutions, namely, in-fiber interferometers based on the suspended-core or suspended-multi-core fiber, for physical parameter monitoring.info:eu-repo/semantics/publishedVersio

Specific configuration of dendritic degeneration in pyramidal neurons of the medial prefrontal cortex induced by differing corticosteroid regimens

We previously demonstrated that hypercorticalism induces pronounced volumetric reductions in the rat medial prefrontal cortex (mPFC) and that these structural changes correlate with deficits in executive function. By applying 3-dimensional analysis of Golgi-Cox-stained material, we now demonstrate that corticosteroids can exert differential effects on dendritic arborizations of pyramidal neurons in lamina II/III of the mPFC. Treatment with the glucocorticoid receptor-selective agonist dexamethasone and with the natural adrenosteroid, corticosterone (CORT), results in significant reductions in the total length of apical dendrites in the pyramidal neurons in lamina II/III of the anterior cingulate/prelimbic and infralimbic cortices. Interestingly, although these treatments do not affect the number of dendritic branches, they are associated with impoverished arborizations in their distal portions and, in CORT-treated animals, with increased branching in the middle portions of the apical dendritic tree. Deprivation of corticosteroids by adrenalectomy leads to decreases in total apical dendritic length and spine number, but in this case, dendritic impoverishment was restricted to the middle/proximal segments of the dendritic trees. None of the treatments influenced the architecture of the basal dendrites. These results add to our knowledge of the morphological substrates through which corticosteroids may disrupt mPFC-dependent behaviors.Part of this work was supported by an Accões Integradas Luso-Alemãs grant from the German Academic Exchange Service (DAAD) and the Portuguese Rectors’ Conference

A versatile nanocarrierCubosomes, characterization, and applications

The impact of nanotechnology on the exponential growth of several research areas, particularly nanomedicine, is undeniable. The ability to deliver active molecules to the desired site could significantly improve the efficiency of medical treatments. One of the nanocarriers developed which has drawn researchers’ attention are cubosomes, which are nanosized dispersions of lipid bicontinuous cubic phases in water, consisting of a lipidic interior and aqueous domains folded in a cubic lattice. They stand out due to their ability to incorporate hydrophobic, hydrophilic, and amphiphilic compounds, their tortuous internal configuration that provides a sustained release, and the capacity to protect and safely deliver molecules. Several approaches can be taken to prepare this structure, as well as different lipids like monoolein or phytantriol. This review paper describes the different methods to prepare nanocarriers. As it is known, the physicochemical properties of nanocarriers are very important, as they influence their pharmacokinetics and their ability to incorporate and deliver active molecules. Therefore, an extensive characterization is essential to obtain the desired effect. As a result, we have extensively described the most common techniques to characterize cubosomes, particularly nanocarriers. The exceptional properties of the cubosomes make them suitable to be used in several applications in the biomedical field, from cancer therapeutics to imaging, which will be described. Taking in consideration the outstanding properties of cubosomes, their application in several research fields is envisaged.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, by Marie Skłodowska Curie grant (MSCA-RISE; FODIAC; 778388) and by European Regional Development Fund (ERDF) through the Competitiveness factors Operational program—Norte 2020, COMPETE and National Funds through the FCT—under the project AgriFood XXI (NORTE- 01-0145-FEDER-000041). J.L.P. acknowledge the Instituto de Salud Carlos III for a “Sara Borrell” grant (CD19/00250), cofounded by European Social Fund (“El FSE invierte en futuro”). C.J.O.F. acknowledge the FCT for the grant SFRH/149/BD/14199/2019.info:eu-repo/semantics/publishedVersio

In Vitro CRISPR/Cas9 Transfection and Gene-Editing Mediated by Multivalent Cationic LiposomeDNA Complexes

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated nuclease 9 (Cas9) gene-editing offers exciting new therapeutic possibilities for disease treatment with a genetic etiology such as cancer, cardiovascular, neuronal, and immune disorders. However, its clinical translation is being hampered by the lack of safe, versatile, and effective nonviral delivery systems. Herein we report on the preparation and application of two cationic liposome–DNA systems (i.e., lipoplexes) for CRISPR/Cas9 gene delivery. For that purpose, two types of cationic lipids are used (DOTAP, monovalent, and MVL5, multivalent with +5e nominal charge), along with three types of helper lipids (DOPC, DOPE, and monoolein (GMO)). We demonstrated that plasmids encoding Cas9 and single-guide RNA (sgRNA), which are typically hard to transfect due to their large size (>9 kb), can be successfully transfected into HEK 293T cells via MVL5-based lipoplexes. In contrast, DOTAP-based lipoplexes resulted in very low transfection rates. MVL5-based lipoplexes presented the ability to escape from lysosomes, which may explain the superior transfection efficiency. Regarding gene editing, MVL5-based lipoplexes achieved promising GFP knockout levels, reaching rates of knockout superior to 35% for charge ratios (+/−) of 10. Despite the knockout efficiency being comparable to that of Lipofectamine 3000® commercial reagent, the non-specific gene knockout is more pronounced in MVL5-based formulations, probably resulting from the considerable cytotoxicity of these formulations. Altogether, these results show that multivalent lipid-based lipoplexes are promising CRISPR/Cas9 plasmid delivery vehicles, which by further optimization and functionalization may become suitable in vivo delivery systems.This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte and the Project FCOMP-01– 0124-FEDER-021053 (PTDC/SAU-BMA/121028/2010). This research was also supported by the Microfluidic Layer-by-layer Assembly of Cationic Liposome—Nucleic Acid Nanoparticles for Gene Delivery project (032520) co-funded by FCT and the ERDF through COMPETE2020. Diana A. Sousa (D.A.S) and Celso J.O. Ferreira (C.J.O.F) acknowledge FCT for the grants PD/BD/139083/2018 and SFRH/BD/149199/2019, respectively.info:eu-repo/semantics/publishedVersio

Tradução, adaptação cultural e validação do Inventário da Prática Centrada na Pessoa, profissionais de saúde (PCPI-S)

Aiming to translate, culturally adapt, and psychometrically evaluate the Person-centred Practice Inventory – Staff (PCPI-S) for Portuguese healthcare professionals, this methodological study was conducted sequentially in two phases. Phase I followed the 10-steps recommendations from the ISPOR taskforce for translation and cultural adaptation of patient reported outcome measures. Phase II comprised a quantitative cross-sectional virtual survey of the translated PCPI-S with healthcare professionals, who were reached through snowball sampling from both primary and specialized care settings. The psychometric properties of the PCPI-S were determined by assessing reliability and construct validity. A sample of 304 healthcare professionals participated in Phase II. Ceiling effects were found. The overall internal consistency was excellent (>0.9). The confirmatory factor analysis showed a good model fit after minor modifications, revealing construct validity, and supporting the theoretical framework. In conclusion, the three-factorial model of PCPI-S adjusted to the studied sample is a valid and reliable instrument to assess the perceptions of healthcare professionals on person-centred practice in various Portuguese clinical contexts. Considering the ceiling effects, the effect of social desirability should be explored.Com o objetivo de traduzir, adaptar culturalmente e avaliar psicometricamente o Inventário para a Prática Centrada na Pessoa para profissionais de saúde (PCPI-S) em diversos contextos de prestação de cuidados, este estudo metodológico realizou-se em duas fases sequenciais. A Fase I seguiu as recomendações de dez etapas da taskforce da ISPOR para tradução e adaptação cultural de medidas de resultados auto reportados. A Fase II incluiu um estudo cross-sectional do PCPI-S traduzido com profissionais de saúde, que foram alcançados por meio de amostragem snowball em contextos de cuidados primários e diferenciados. A psicometria do PCPI-S foi analisada pela avaliação da confiabilidade e validade de construto. Uma amostra de 304 profissionais de saúde participou da Fase II. Efeitos de teto foram encontrados. A consistência interna geral foi excelente (> 0,9). A análise fatorial confirmatória mostrou um bom ajuste do modelo e validade de construto, refletindo o referencial teórico. Concluindo, o modelo tri-fatorial do PCPI-S ajustado à amostra estudada é um instrumento válido e fiável para avaliar as percepções dos profissionais de saúde sobre a prática centrada na pessoa em vários contextos de cuidados portugueses. Considerando os efeitos teto, a desejabilidade social deve ser explorada.info:eu-repo/semantics/publishedVersio

Real-Time Demonstration of Low-Complexity Time-Domain Chromatic Dispersion Equalization

We demonstrate real-time CD equalization (CDE) for coherent optical transmission systems using a low complexity time-domain (TD) multiplierless finite-impulse response (FIR)-based equalizer, based on a field-programmable gate array (FPGA) implementation. The real-time operation is performed for a single-channel 2.5 Gb/s QPSK optical signal with a performance penalty of only 0.15 dB with respect to the maximum performance. The hardware complexity is also evaluated in terms of occupation in a Virtex-6 FPGA-XC6VLX240T, revealing the high efficiency of the proposed CDE algorithm

Back to the Future: Conserving Functional and Phylogenetic Diversity in the Amphibian-Climate Refuges

Climate refuges have been used by several species over historical climate change. Ectothermic species often display good models for climate change studies because they are highly sensitive to temperature. Analysis of species loss with ecosystem and evolutionary values helps to understand environmental processes and climate change consequences. We determined the functional and phylogenetic diversity of amphibians in the Atlantic Forest hotspot, using multiple models representing present and future conditions. Through a novel approach, we predict species’ threat status by 2080, following the IUCN’s criterion B1. Our results estimate a drastic reduction in species richness, ecosystem functioning and evolutionary history at low latitudes and altitudes. We show that species will tend to disperse to the areas with milder temperatures (i.e., high latitudes/altitudes). Some of these areas are the same climate refuges that have been suggested for the Late Pleistocene. We highlight that 60% of amphibians can become threatened under predicted-future conditions. This work advances the knowledge on climate refuges for amphibian ecology and evolution, supporting complementary tools for conservation strategies