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2021
Square planar Au(III), Pt(II) and Cu(II) complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligands: From in vitro to in vivo biological properties, Choroba, Katarzyna, Machura Barbara, Szlapa-Kula Agata, Malecki {Jan G. }, Raposo Luis, Roma-Rodrigues Catarina, Cordeiro Sandra, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , European Journal of Medicinal Chemistry, jun, Volume 218, (2021) Abstract

Cancer is the second leading cause of death worldwide. Cisplatin has challenged cancer treatment; however, resistance and side effects hamper its use. New agents displaying improved activity and more reduced side effects relative to cisplatin are needed. In this work we present the synthesis, characterization and biological activities of three complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligand: [Pt(4′-(2-quin)-terpy)Cl](SO3CF3) (1), [Au(4′-(2-quin)-terpy)Cl](PF6)2·CH3CN (2) and [Cu(4′-(2-quin)-terpy)Cl](PF6) (3). The three complexes displayed a high antiproliferative activity in ovarian carcinoma cell line (A2780) and even more noticeable in a colorectal carcinoma cell line (HCT116) following the order 3 > 2 > 1. The complexes IC50 are at least 20 × lower than the IC50 displayed by cisplatin (15.4 μM) in HCT116 cell line while displaying at the same time, much reduced cytotoxicity in a normal dermal fibroblast culture. These cytotoxic activities seem to be correlated with the inclination angles of 2-quin unit to the central pyridine. Interestingly, all complexes can interact with calf-thymus DNA (CT-DNA) in vitro via different mechanisms, although intercalation seems to be the preferred mechanism at least for 2 and 3 at higher concentrations of DNA. Moreover, circular dichroism (CD) data seems to indicate that complex 3, more planar, induces a high destabilization of the DNA double helix (shift from B-form to Z-form). Higher the deviation from planar, the lower the cytotoxicity displayed by the complexes. Cellular uptake may be also responsible for the different cytotoxicity exhibited by complexes with 3 > 2 >1. Complex 2 seems to enter cells more passively while complex 1 and 3 might enter cells via energy-dependent and -independent mechanisms. Complexes 1–3 were shown to induce ROS are associated with the increased apoptosis and autophagy. Moreover, all complexes dissipate the mitochondrial membrane potential leading to an increased BAX/BCL-2 ratio that triggered apoptosis. Complexes 2 and 3 were also shown to exhibit an anti-angiogenic effect by significantly reduce the number of newly formed blood vessel in a CAM model with no toxicity in this in vivo model. Our results seem to suggest that the increased cytotoxicity of complex 3 in HCT116 cells and its potential interest for further translation to pre-clinical mice xenografts might be associated with: 1) higher % of internalization of HCT116 cells via energy-dependent and -independent mechanisms; 2) ability to intercalate DNA and due to its planarity induced higher destabilization of DNA; 3) induce intracellular ROS that trigger apoptosis and autophagy; 4) low toxicity in an in vivo model of CAM; 5) potential anti-angiogenic effect.

Benchtop X-ray fluorescence imaging as a tool to study gold nanoparticle penetration in 3D cancer spheroids, Pedrosa, Pedro, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Guerra Mauro , RSC Advances, jul, Volume 11, Number 42, p.26344–26353, (2021) Abstract

The use of nanomaterials to improve medical diagnostics and therapeutics has been rapidly increasing. Among these materials are gold nanoparticles, which can be functionalized to target specific cells, acting as nanovectors for drug delivery, enhanced contrast agents as well as other targeted therapies. Au nanoparticles are very useful as they selectively accumulate in tumour sites due to the enhanced permeability-retention effect. There is however little information about the spatial distribution of the nanoparticles within tumours, which might hinder efficient therapies. In this study, X-ray fluorescence was used to investigate the diffusion of gold nanoparticles in cancer cell spheroids mimicking true tumour growth. Functionalization of the nanoparticles has the effect of allowing better diffusion into and out of the spheroid, while those nanoparticles that are only partially covered rapidly formed aggregates. This clustering led to size exclusion during transport within the tumour, changing its distribution profile while greatly increasing the nanoparticle concentration.

Exploiting the antiproliferative potential of spiropyrazoline oxindoles in a human ovarian cancer cell line, Raposo, {Luís R. }, Silva {Ana Rute}, Silva Dário, Roma-Rodrigues Catarina, Espadinha Margarida, Baptista {Pedro V. }, Santos {Maria M. M. }, and Fernandes {Alexandra R. } , Bioorganic and Medicinal Chemistry, jan, Volume 30, (2021) Abstract

Cancer is still one of the deadliest diseases worldwide despite the efforts in its early detection and treatment strategies. However, most chemotherapeutic agents still present side effects in normal tissues and acquired resistance that limit their efficacy. Spiropyrazoline oxindoles might be good alternatives as they have shown antiproliferative activity in human breast and colon cancer cell lines, without eliciting cytotoxicity in healthy cells. However, their potential for ovarian cancer was never tested. In this work, the antiproliferative activity of five spiropyrazoline oxindoles was assessed in ovarian cancer cells A2780 and the biological targets and mechanism of action of the most promising compound evaluated. Compound 1a showed the highest antiproliferative effect, as well as the highest selectivity for A2780 cells compared to healthy fibroblasts. This antiproliferative effect results from the induction of cell death by mitochondria-mediated apoptosis and autophagy. In vitro DNA interaction studies demonstrated that 1a interacts with DNA by groove-binding, without triggering genotoxicity. In addition, 1a showed a strong affinity to bovine serum albumin that might be important for further inclusion in drug delivery platforms. Proteomic studies reinforced 1a role in promoting A2780 endoplasmatic reticulum (ER) stress by destabilizing the correct protein folding which triggers cell death via apoptosis and autophagy.

Specific Antiproliferative Properties of Proteinaceous Toxin Secretions from the Marine Annelid Eulalia sp. onto Ovarian Cancer Cells, Rodrigo, {Ana P. }, Mendes {Vera M. }, Manadas Bruno, Grosso {Ana R. }, {Alves de Matos} {António P. }, Baptista {Pedro V. }, Costa {Pedro M. }, and Fernandes {Alexandra R. } , Marine Drugs, jan, Volume 19, Number 1, (2021) Abstract

As Yondelis joins the ranks of approved anti-cancer drugs, the benefit from exploring the oceans' biodiversity becomes clear. From marine toxins, relevant bioproducts can be obtained due to their potential to interfere with specific pathways. We explored the cytotoxicity of toxin-bearing secretions of the polychaete Eulalia onto a battery of normal and cancer human cell lines and discovered that the cocktail of proteins is more toxic towards an ovarian cancer cell line (A2780). The secretions' main proteins were identified by proteomics and transcriptomics: 14-3-3 protein, Hsp70, Rab3, Arylsulfatase B and serine protease, the latter two being known toxins. This mixture of toxins induces cell-cycle arrest at G2/M phase after 3h exposure in A2780 cells and extrinsic programmed cell death. These findings indicate that partial re-activation of the G2/M checkpoint, which is inactivated in many cancer cells, can be partly reversed by the toxic mixture. Protein-protein interaction networks partake in two cytotoxic effects: cell-cycle arrest with a link to RAB3C and RAF1; and lytic activity of arylsulfatases. The discovery of both mechanisms indicates that venomous mixtures may affect proliferating cells in a specific manner, highlighting the cocktails' potential in the fine-tuning of anti-cancer therapeutics targeting cell cycle and protein homeostasis.

A Transcriptomic Approach to the Recruitment of Venom Proteins in a Marine Annelid, Rodrigo, {Ana P. }, Grosso {Ana R. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Costa {Pedro M. } , Toxins, jan, Volume 13, Number 2, (2021) Abstract

The growing number of known venomous marine invertebrates indicates that chemical warfare plays an important role in adapting to diversified ecological niches, even though it remains unclear how toxins fit into the evolutionary history of these animals. Our case study, the Polychaeta Eulalia sp., is an intertidal predator that secretes toxins. Whole-transcriptome sequencing revealed proteinaceous toxins secreted by cells in the proboscis and delivered by mucus. Toxins and accompanying enzymes promote permeabilization, coagulation impairment and the blocking of the neuromuscular activity of prey upon which the worm feeds by sucking pieces of live flesh. The main neurotoxins ({"}phyllotoxins{"}) were found to be cysteine-rich proteins, a class of substances ubiquitous among venomous animals. Some toxins were phylogenetically related to Polychaeta, Mollusca or more ancient groups, such as Cnidaria. Some toxins may have evolved from non-toxin homologs that were recruited without the reduction in molecular mass and increased specificity of other invertebrate toxins. By analyzing the phylogeny of toxin mixtures, we show that Polychaeta is uniquely positioned in the evolution of animal venoms. Indeed, the phylogenetic models of mixed or individual toxins do not follow the expected eumetazoan tree-of-life and highlight that the recruitment of gene products for a role in venom systems is complex.

Cu(i) complexes as new antiproliferative agents against sensitive and doxorubicin resistant colorectal cancer cells: synthesis, characterization, and mechanisms of action, Sequeira, Diogo, Baptista {Pedro V. }, Valente Ruben, Piedade Fátima {M. M. M. }, Garcia Helena} {M., Morais {Tânia S. }, and Fernandes {Alexandra R. } , Dalton Transactions, feb, Volume 50, Number 5, p.1845–1865, (2021) Abstract

Cancer is one of the worst health issues worldwide, representing the second leading cause of death. Current chemotherapeutic drugs face some challenges like the acquired resistance of the tumoral cells and low specificity leading to unwanted side effects. There is an urgent need to develop new compounds that may target resistant cells. The synthesis and characterization of two Cu(i) complexes of general formula [Cu(PP)(LL)][BF4], where PP is a phosphane ligand (triphenylphosphine or 1,2-bis(diphenylphosphano) ethane) and LL = is a heteroaromatic bidentate ligand (4,4′-dimethyl-2,2′-bipyridine and 6,3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine). The new compounds were fully characterized by spectroscopic techniques (NMR, FTIR and UV-vis.), elemental analysis (C, H, N and S) and two structures were determined by single X-ray diffraction studies. The antiproliferative potential of the new Cu(i) complexes were studied in tumor (breast adenocarcinoma, ovarian carcinoma and in colorectal carcinoma sensitive and resistant to doxorubicin) and normal (fibroblasts) cell lines. Complexes1-4did not show any antiproliferative potential. Amongst the complexes5-8, complex8shows high cytotoxic potential against colorectal cancer sensitive and resistant to doxorubicin and low cytotoxicity towards healthy cells. We show that complexes5-8can cleave pDNA and, in particular, thein vitropDNA cleavage is due to an oxidative mechanism. This oxidative mechanism corroborates the induction of reactive oxygen species (ROS), that triggers HCT116 cell deathviaapoptosis, as proved by the increased expression of BAX protein relative to BCL-2 protein and the depolarization of mitochondrial membrane potential, andviaautophagy. Additionally, complex8can block the cell cycle in the G1 phase, also exhibiting a cytostatic potential. Proteomic analysis confirmed the apoptotic, autophagic and cytostatic potential of complex8, as well as its ability to produce ROS and cause DNA damage. The interference of the complex in folding and protein synthesis and its ability to cause post-translational modifications was also verified. Finally, it was observed that the complex causes a reduction in cellular metabolism. The results herein demonstrated the potential of Cu(i) complexes in targeting doxorubicin sensitive and resistant cells which is positive and must be further explored usingin vivoanimal models.

Aggregation versus Biological Activity in Gold(I) Complexes. An Unexplored Concept, Pinto, Andrea, Roma-Rodrigues Catarina, Ward {Jas S. }, Puttreddy Rakesh, Rissanen Kari, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Lima {João Carlos}, and Rodríguez Laura , Inorganic Chemistry, dec, Volume 60, Number 24, p.18753–18763, (2021) Abstract

The aggregation process of a series of mono- and dinuclear gold(I) complexes containing a 4-ethynylaniline ligand and a phosphane at the second coordination position (PR3-Au-CCC6H4-NH2, complexes 1-5, and (diphos)(Au-CCC6H4-NH2)2, complexes 6-8), whose biological activity was previously studied by us, has been carefully analyzed through absorption, emission, and NMR spectroscopy, together with dynamic light scattering and small-angle X-ray scattering. These experiments allow us to retrieve information about how the compounds enter the cells. It was observed that all compounds present aggregation in fresh solutions, before biological treatment, and thus they must be entering the cells as aggregates. Inductively coupled plasma atomic emission spectrometry measurements showed that mononuclear complexes are mainly found in the cytosolic fraction; the dinuclear complexes are mainly found in a subsequent fraction composed of nuclei and cytoskeleton. Additionally, dinuclear complex 8 affects the actin aggregation to a larger extent, suggesting a cooperative effect of dinuclear compounds.

Drug delivery nanosystems targeted to hepatic ischemia and reperfusion injury, Ferreira-Silva, Margarida, Faria-Silva Catarina, Baptista {Pedro Viana}, Fernandes Eduarda, Fernandes {Alexandra Ramos}, and Corvo {Maria Luísa} , Drug delivery and translational research, apr, Volume 11, Number 2, p.397–410, (2021) Abstract

Abstract: Hepatic ischemia and reperfusion injury (IRI) is an acute inflammatory process that results from surgical interventions, such as liver resection surgery or transplantation, or hemorrhagic shock. This pathology has become a severe clinical issue, due to the increasing incidence of hepatic cancer and the high number of liver transplants. So far, an effective treatment has not been implemented in the clinic. Despite its importance, hepatic IRI has not attracted much interest as an inflammatory disease, and only a few reviews addressed it from a therapeutic perspective with drug delivery nanosystems. In the last decades, drug delivery nanosystems have proved to be a major asset in therapy because of their ability to optimize drug delivery, either by passive or active targeting. Passive targeting is achieved through the enhanced permeability and retention (EPR) effect, a main feature in inflammation that allows the accumulation of the nanocarriers in inflammation sites, enabling a higher efficacy of treatment than conventional therapies. These systems also can be actively targeted to specific compounds, such as inflammatory markers and overexpressed receptors in immune system intermediaries, allowing an even more specialized therapy that have already showed encouraging results. In this manuscript, we review drug delivery nanosystems designed for hepatic IRI treatment, addressing their current state in clinical trials, discussing the main hurdles that hinder their successful translation to the market and providing some suggestions that could potentially advance their clinical translation. Graphical abstract: [Figure not available: see fulltext.].

Genetic predisposition for aggressive behaviour related with dopamine and serotonin pathways - an overview, Paulino, Cathy, Fernandes {Alexandra R. }, Baptista {Pedro V. }, Soeiro Cristina, Grosso {Ana Rita}, and Quintas Alexandre , Annals of Medicine, apr, Volume 53, Number SI, p.S77–S77, (2021) Abstract
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The genetic susceptibility linking preterm birth and periodontal disease a review, Couceiroa, Joana, Grosso {Ana Rita}, Baptista {Pedro V. }, Mendes {Jose J. }, Fernandes {Alexandra R. }, and Quintas Alexandre , Annals of Medicine, apr, Volume 53, Number SI, p.S16–S17, (2021) Abstract
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Liposomal nanosystems in rheumatoid arthritis, Ferreira-Silva, Margarida, Faria-Silva Catarina, Baptista {Pedro Viana}, Fernandes Eduarda, Fernandes {Alexandra Ramos}, and Corvo {Maria Luísa} , Pharmaceutics, apr, Volume 13, Number 4, (2021) Abstract

Rheumatoid arthritis (RA) is an autoimmune disease that affects the joints and results in reduced patient quality of life due to its chronic nature and several comorbidities. RA is also associated with a high socioeconomic burden. Currently, several available therapies minimize symptoms and prevent disease progression. However, more effective treatments are needed due to current therapies’ severe side-effects, especially under long-term use. Drug delivery systems have demonstrated their clinical importance—with several nanocarriers present in the market—due to their capacity to improve therapeutic drug index, for instance, by enabling passive or active targeting. The first to achieve market authorization were liposomes that still represent a considerable part of approved delivery systems. In this manuscript, we review the role of liposomes in RA treatment, address preclinical studies and clinical trials, and discuss factors that could hamper a successful clinical translation. We also suggest some alterations that could potentially improve their progression to the market.

Cation-mediated gelation of the fucose-rich polysaccharide FucoPol: preparation and characterization of hydrogel beads and their cytotoxicity assessment, Fialho, Letícia, Araújo Diana, Alves {Vitor D. }, Roma-Rodrigues Catarina, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Freitas Filomena, and Reis {Maria A. M. } , International Journal of Polymeric Materials and Polymeric Biomaterials, Volume 70, Number 2, (2021) Abstract

This study describes for the first time the iron- and copper-mediated gelation of FucoPol, fucose-rich bacterial polysaccharide. The ability of FucoPol to gel in the presence of metal cations, including iron(III) and copper(II), was used for the preparation of hydrogel beads. Iron mediated the formation of stable and not cytotoxic gel beads, while copper resulted in fragile and cytotoxic ones. Copper-mediated beads coated with an iron-mediated gel layer were more stable and had reduced cytotoxicity. The resulting polymeric structures had differing morphology, physical properties and cytotoxicity, which support their use in several applications, including biomedicine, agriculture and bioremediation.

Isothermal Amplification of Nucleic Acids: The Race for the Next “Gold Standard”, Oliveira, {Beatriz B. }, Veigas Bruno, and Baptista {Pedro Viana} , Frontiers in Sensors, Volume 2, (2021) Abstract

Nucleic acid amplification technologies (NAATs) have become fundamental tools in molecular diagnostics, due to their ability to detect small amounts of target molecules. Since its development, Polymerase Chain Reaction (PCR) has been the most exploited method, being stablished as the “gold standard” technique for DNA amplification. However, the requirement for different working temperatures leads to the need of a thermocycler machine or complex thermal apparatus, which have been preventing its application in novel integrated devices for single workflow and high throughput analysis. Conversely, isothermal amplification methods have been gaining attention, especially for point-of-care diagnosis and applications. These non-PCR based methods have been developed by mimicking the in vivo amplification mechanisms, while performing the amplification with high sensitivity, selectivity and allowing for high-throughput analysis. These favorable capabilities have pushed forward the implementation and commercialization of several platforms that exploit isothermal amplification methods, mostly against virus, bacteria and other pathogens in water, food, environmental and clinical samples. Nevertheless, the future of isothermal amplification methods is still dependent on achieving technical maturity and broader commercialization of enzymes and reagents.

2020
The intracellular number of magnetic nanoparticles modulates the apoptotic death pathway after magnetic hyperthermia treatment, Beola, Lilianne, Asín Laura, Roma-Rodrigues Catarina, Fernandez-Afonso Yilian, Fratila {Raluca M. }, Serantes David, Ruta Sergiu, Chantrell {Roy W. }, Fernandes {Alexandra R. }, Baptista {Pedro V. }, {de la Fuente} {Jesus M. }, Grazu Valeria, and Gutierrez Lucía , ACS Applied Materials & Interfaces, sep, Volume 12, Number 39, p.43474–43487, (2020) Abstract

Magnetic hyperthermia is a cancer treatment based on the exposure of magnetic nanoparticles to an alternating magnetic field in order to generate local heat. In this work, 3D cell culture models were prepared to observe the effect that a different number of internalized particles had on the mechanisms of cell death triggered upon the magnetic hyperthermia treatment. Macrophages were selected by their high capacity to uptake nanoparticles. Intracellular nanoparticle concentrations up to 7.5 pg Fe/cell were measured both by elemental analysis and magnetic characterization techniques. Cell viability after the magnetic hyperthermia treatment was decreased to <25% for intracellular iron contents above 1 pg per cell. Theoretical calculations of the intracellular thermal effects that occurred during the alternating magnetic field application indicated a very low increase in the global cell temperature. Different apoptotic routes were triggered depending on the number of internalized particles. At low intracellular magnetic nanoparticle amounts (below 1 pg Fe/cell), the intrinsic route was the main mechanism to induce apoptosis, as observed by the high Bax/Bcl-2 mRNA ratio and low caspase-8 activity. In contrast, at higher concentrations of internalized magnetic nanoparticles (1−7.5 pg Fe/cell), the extrinsic route was observed through the increased activity of caspase-8. Nevertheless, both mechanisms may coexist at intermediate iron concentrations. Knowledge on the different mechanisms of cell death triggered after the magnetic hyperthermia treatment is fundamental to understand the biological events activated by this procedure and their role in its effectiveness.

Hyperthermia induced by gold nanoparticles and visible light photothermy combined with chemotherapy to tackle doxorubicin sensitive and resistant colorectal tumor 3D spheroids, Roma-Rodrigues, Catarina, Pombo Inês, Fernandes {Alexandra R. }, and Baptista {Pedro V. } , International Journal of Molecular Sciences, oct, Volume 21, Number 21, p.1–13, (2020) Abstract

Current cancer therapies are frequently ineffective and associated with severe side effects and with acquired cancer drug resistance. The development of effective therapies has been hampered by poor correlations between pre-clinical and clinical outcomes. Cancer cell-derived spheroids are three-dimensional (3D) structures that mimic layers of tumors in terms of oxygen and nutrient and drug resistance gradients. Gold nanoparticles (AuNP) are promising therapeutic agents which permit diminishing the emergence of secondary effects and increase therapeutic efficacy. In this work, 3D spheroids of Doxorubicin (Dox)-sensitive and -resistant colorectal carcinoma cell lines (HCT116 and HCT116-DoxR, respectively) were used to infer the potential of the combination of chemotherapy and Au-nanoparticle photothermy in the visible (green laser of 532 nm) to tackle drug resistance in cancer cells. Cell viability analysis of 3D tumor spheroids suggested that AuNPs induce cell death in the deeper layers of spheroids, further potentiated by laser irradiation. The penetration of Dox and earlier spheroid disaggregation is potentiated in combinatorial therapy with Dox, AuNP functionalized with polyethylene glycol (AuNP@PEG) and irradiation. The time point of Dox administration and irradiation showed to be important for spheroids destabilization. In HCT116-sensitive spheroids, pre-irradiation induced earlier disintegration of the 3D structure, while in HCT116 Dox-resistant spheroids, the loss of spheroid stability occurred almost instantly in post-irradiated spheroids, even with lower Dox concentrations. These results point towards the application of new strategies for cancer therapeutics, reducing side effects and resistance acquisition.

Tackling Multidrug Resistance in Streptococci: From Novel Biotherapeutic Strategies to Nanomedicines, Alves-Barroco, Cinthia, Rivas-García Lorenzo, Fernandes {Alexandra R. }, and Baptista {Pedro Viana} , Frontiers in Microbiology, oct, Volume 11, (2020) Abstract

The pyogenic streptococci group includes pathogenic species for humans and other animals and has been associated with enduring morbidity and high mortality. The main reason for the treatment failure of streptococcal infections is the increased resistance to antibiotics. In recent years, infectious diseases caused by pyogenic streptococci resistant to multiple antibiotics have been raising with a significant impact to public health and veterinary industry. The rise of antibiotic-resistant streptococci has been associated to diverse mechanisms, such as efflux pumps and modifications of the antimicrobial target. Among streptococci, antibiotic resistance emerges from previously sensitive populations as result of horizontal gene transfer or chromosomal point mutations due to excessive use of antimicrobials. Streptococci strains are also recognized as biofilm producers. The increased resistance of biofilms to antibiotics among streptococci promote persistent infection, which comprise circa 80% of microbial infections in humans. Therefore, to overcome drug resistance, new strategies, including new antibacterial and antibiofilm agents, have been studied. Interestingly, the use of systems based on nanoparticles have been applied to tackle infection and reduce the emergence of drug resistance. Herein, we present a synopsis of mechanisms associated to drug resistance in (pyogenic) streptococci and discuss some innovative strategies as alternative to conventional antibiotics, such as bacteriocins, bacteriophage, and phage lysins, and metal nanoparticles. We shall provide focused discussion on the advantages and limitations of agents considering application, efficacy and safety in the context of impact to the host and evolution of bacterial resistance.

Correction to: Nano-in-Micro Sildenafil Dry Powder Formulations for the Treatment of Pulmonary Arterial Hypertension Disorders: The Synergic Effect of POxylated Polyurea Dendrimers, PLGA, and Cholesterol (Part. Part. Syst. Charact, (2020), 37, (1900447), , Restani, {Rita B. }, Tavares {Márcia T. }, Pires {Rita F. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Casimiro Teresa, Bonifácio {Vasco D. B. }, and Aguiar-Ricardo Ana , Particle and Particle Systems Characterization, nov, Volume 37, Number 11, (2020) Abstract

Part. Part. Syst. Charact. 2020, 37, 1900447 In the originally published manuscript, the author Márcia T. Tavares was omitted. The author is hereby added in the author byline and is associated with the first affiliation.

Water safety screening via multiplex LAMP-Au-nanoprobe integrated approach, Oliveira, {Beatriz B. }, Veigas Bruno, Carlos {Fábio Ferreira}, Sánchez-Melsió Alexandre, Balcázar {José Luís}, Borrego {Carles M. }, and Baptista {Pedro Viana} , Science of the Total Environment, nov, Volume 741, (2020) Abstract

Contaminated water resources remain a major global concern regarding public health. The majority of water safety protocols include indicators of microbial contamination to evaluate the potential risk to public health and are key elements of quality guidelines. Among these, markers for total coliforms and fecal coliforms are strong indicators of co-contamination with other pathogens. Traditional methods, recurring to slow and cumbersome culture-based approaches, have been gradually replaced by molecular methods, capable of faster and more specific screening. These are usually PCR-based methods that may allow for multiple pathogen detection but require dedicated laboratory equipment, hindering the rapid on-site assessment. Here, we used a multiplex Loop-Mediated Isothermal Amplification (mLAMP) strategy for the amplification of two markers associated with the contamination by total and fecal coliforms (e.g. Escherichia coli) — lacZ and uidA genes, respectively — thus allowing for single tube multiplex detection. The mLAMP products were then subject to an Au-nanoprobe colorimetric detection assay for precise discrimination of targets. This approach was validated in 22 water samples that were also screened for the presence of lacZ and uidA using standard and quantitative PCR, with the capability for discriminating the contamination level, e.g. a semi-quantitative evaluation of water quality.

Fast prototyping microfluidics: Integrating droplet digital lamp for absolute quantification of cancer biomarkers, Oliveira, Beatriz, Veigas Bruno, Fernandes {Alexandra R. }, Águas Hugo, Martins Rodrigo, Fortunato Elvira, and Baptista {Pedro Viana} , Sensors, mar, Volume 20, Number 6, (2020) Abstract

Microfluidic (MF) advancements have been leveraged toward the development of state-of-the-art platforms for molecular diagnostics, where isothermal amplification schemes allow for further simplification of DNA detection and quantification protocols. The MF integration with loop-mediated isothermal amplification (LAMP) is today the focus of a new generation of chip-based devices for molecular detection, aiming at fast and automated nucleic acid analysis. Here, we combined MF with droplet digital LAMP (ddLAMP) on an all-in-one device that allows for droplet generation, target amplification, and absolute quantification. This multilayer 3D chip was developed in less than 30 minutes by using a low-cost and extremely adaptable production process that exploits direct laser writing technology in “Shrinky-dinks” polystyrene sheets. ddLAMP and target quantification were performed directly on-chip, showing a high correlation between target concentration and positive droplet score. We validated this integrated chip via the amplification of targets ranging from five to 500,000 copies/reaction. Furthermore, on-chip amplification was performed in a 10 µL volume, attaining a limit of detection of five copies/µL under 60 min. This technology was applied to quantify a cancer biomarker, c-MYC, but it can be further extended to any other disease biomarker.

Gene therapy in cancer treatment: Why go nano?, Roma-Rodrigues, Catarina, Rivas-García Lorenzo, Baptista {Pedro V. }, and Fernandes {Alexandra R. } , Pharmaceutics, mar, Volume 12, Number 3, (2020) Abstract

The proposal of gene therapy to tackle cancer development has been instrumental for the development of novel approaches and strategies to fight this disease, but the efficacy of the proposed strategies has still fallen short of delivering the full potential of gene therapy in the clinic. Despite the plethora of gene modulation approaches, e.g., gene silencing, antisense therapy, RNA interference, gene and genome editing, finding a way to efficiently deliver these effectors to the desired cell and tissue has been a challenge. Nanomedicine has put forward several innovative platforms to overcome this obstacle. Most of these platforms rely on the application of nanoscale structures, with particular focus on nanoparticles. Herein, we review the current trends on the use of nanoparticles designed for cancer gene therapy, including inorganic, organic, or biological (e.g., exosomes) variants, in clinical development and their progress towards clinical applications.

Nano-in-Micro Sildenafil Dry Powder Formulations for the Treatment of Pulmonary Arterial Hypertension Disorders: The Synergic Effect of POxylated Polyurea Dendrimers, PLGA, and Cholesterol, Restani, {Rita B. }, Pires {Rita F. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, Casimiro Teresa, Bonifácio {Vasco D. B. }, and Aguiar-Ricardo Ana , Particle and Particle Systems Characterization, jun, Volume 37, Number 6, (2020) Abstract

POXylated polyurea dendrimer nanoparticles (PUREG4OOx48) are loaded with sildenafil (SDF) by a supercritical carbon dioxide–assisted (scCO2) impregnation. Further supercritical CO2-assisted spray drying (SASD) leads to hybrid nano-in-micro dry powder formulations that are investigated aiming at efficient pulmonary delivery of SDF in pulmonary arterial hypertension treatment. This is the first report of the production of poly(D,L-lactide-co-glycolide)-cholesterol (PLGA-Chol) microparticles processed by SASD. The optimized formulation of nano-in-microparticles is composed of PLGA, Chol, and PUREG4OOx48, loaded with SDF solutions in a 77:23 ratio (PLGA-Chol:dendrimer, w/w). The dry powders are fully characterized and found to be highly biodegradable and biocompatible, and the SDF release profile evaluates under different pH values. The median mass average diameter (MMAD) of the nano-in-micro systems varies between 2.57 and 5 µm and the fine particle fraction (FPF) between 36% and 29% for PUREG4OMeOx48[PLGA-Chol] and PUREG4OEtOx48[PLGA-Chol], respectively. The data validate the potential use of these new formulations in inhalation therapy. In vitro studies are also carried out in order to evaluate the effect of the free drug in cell viability and formulations cytotoxicity.

Synthesis of new hetero-arylidene-9(10H)-anthrone derivatives and their biological evaluation, Roma-Rodrigues, Catarina, Malta Gabriela, Peixoto Daniela, Ferreira {Luísa M. }, Baptista {Pedro V. }, Fernandes {Alexandra R. }, and Branco {Paula S. } , Bioorganic Chemistry, jun, Volume 99, (2020) Abstract

New hetero-arylidene-9(10H)-anthrone derivatives (1) were synthesized from reaction of 1,2-dimethyl-3-alkyl imidazolium salts (2) and 9-anthracenecarboxaldehyde. Ion exchange of the anion with dioctyl sulfosuccinate and lithium bis(trifluoromethanesulfonyl)imide led to the preparation of other derivatives. The antiproliferative effect of the compounds was evaluated in human ovarian (A2780) and colorectal (HCT116) carcinoma cell lines and in normal primary human fibroblasts. Compound 1 presented an antiproliferative effect related to the imidazolium pattern of substitution with compounds having a decyl group at the R-position (1c and 3c) showing the highest cytotoxic activities in all cell lines independently of the counter ion. Compounds 1b and 1c internalize A2780 cancer cells via a passive or an active transport, respectively, inducing A2780 cell death via an extrinsic apoptosis (1b) or intrinsic apoptosis and oncosis (1c). The localization of both compounds in the cytoplasm coupled to the absence of reactive oxygen species (ROS) induction suggest that the mechanisms of toxicity might be different than those of other anthracyclines currently used in chemotherapy.

Light Irradiation of Gold Nanoparticles Toward Advanced Cancer Therapeutics, Amendoeira, Ana, García {Lorenzo Rivas}, Fernandes {Alexandra R. }, and Baptista {Pedro V. } , Advanced Therapeutics, jan, Volume 3, Number 1, (2020) Abstract

Cancer is one of the leading causes of death in the world. To challenge this epidemic, there are growing demands for the development of new advanced and targeted therapeutics capable of effectively tackling cancer cells with improved selectivity. Nanomedicine has put forward several innovative therapeutics toward improving therapeutic efficacy while decreasing the deleterious side effects of current chemotherapy. Multifunctional gold nanoparticles (AuNPs) have been at the core of a plethora of advanced therapeutic strategies that provide selective targeting with their unique optical properties, capable to interact with the light of specific wavelength to deliver therapy with tremendous spatiotemporal precision. AuNPs have been exploited as photodynamic and photothermal therapeutic agents alone or in combination with other cancer treatment modalities with other cancer applications. Due to their exceptional physicochemical properties, they have been proven efficacious allies for photodynamic therapy and for photothermal therapy regimens. Herein, the rapidly progressing literature related to the use of these promising strategies against cancer is discussed, highlighting their possible future clinical translation.

Nanotheranostics in Gene Therapy, Oliveira, {Beatriz B. }, Fernandes {Alexandra R. }, and Baptista {Pedro V. } , Advances in Cancer Nanotheranostics for Experimental and Personalized Medicine, jan, United Kingdom, p.82–115, (2020) Abstract

The continuous advances in molecular genetics have prompt for a wealth of tools capable to modulate genome and the corresponding gene expression. These innovative technologies have broadened the range of possibilities for gene therapy, either to decrease expression of malignant genes and mutations or edition of genomes for correction of errors. These strategies rely on the delivery of therapeutic nucleic acids to cells and tissues that must overcome several biological barriers. Indeed, a key element for the success of any gene therapy formulation is the carrier agent capable to deliver the therapeutic nucleic acid moieties to a specific target and promote efficient cellular uptake, while preventing deleterious off-target effects and degradation by endogenous nucleases. The initial vectorization strategies proved to be rather immunogenic, limited in the amount of genetic material that can be packed and raised severe toxicity concerns. Nowadays, a new generation of nanotechnology-based gene delivery systems are making an impact on the way we use therapeutic nucleic acids. These nanovectorization platforms have been developed so as to show low immunogenicity, low toxicity, ease of assembly and scale-up with higher loading capacity. Some of these nanoscale systems have also allowed for controlled release system and for the simultaneous capability of monitorization of effect - nanotheranostics. Herein, we provide a review on the variety of gene delivery vectors and platforms at the nanoscale.

Porphyrin Pigments in Polychaeta: Explorations on the Evolution of Haem Metabolism in Marine Eumetazoans, Martins, C., Rodrigo {A. P. }, Madeira C., D'Ambrosio M., Goncalves C., Parola {A. J. }, Grosso {A. R. }, Baptista {P. V. }, Fernandes {A. R. }, and Costa {P. M. } , jan, Volume 18, (2020) Abstract
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