Adhesive bioactive coatings inspired by sea life

Inspired by nature, in particular by the marine mussels adhesive proteins (MAPs) and by the tough brick-and-mortar nacre-like structure, novel multilayered films are prepared in the present work. Organic-inorganic multilayered films, with an architecture similar to nacre based on bioactive glass nanoparticles (BG), chitosan and hyaluronic acid modified with catechol groups, which are the main responsible for the outstanding adhesion in MAPs, are developed for the first time. The biomimetic conjugate is prepared by carbodiimide chemistry and analyzed by ultraviolet-visible spectrophotometry. The build-up of the multilayered films is monitored with a quartz crystal microbalance with dissipation monitoring and their topography is characterized by atomic force microscopy. The mechanical properties reveal that the films containing catechol groups and BG present an enhanced adhesion. Moreover, the bioactivity of the films upon immersion in a simulated body fluid solution for 7 days is evaluated by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction. It was found that the constructed films promote the formation of bone-like apatite in vitro. Such multifunctional mussel inspired LbL films, which combine enhanced adhesion and bioactivity, could be potentially used as coatings of a variety of implants for orthopedic applications.The authors want to acknowledge the Portuguese Foundation for Science and Technology (FCT) and the European program FEDER/COMPETE for the financial support through project BioSeaGlue: EXPL/CTM-BIO/0646/2013 (FCOMP-01-0124- FEDER-041105)

Bacillary Prostatitis after Intravesical Immunotherapy: A Rare Adverse Effect

Nowadays, the most efficient form of intravesical immunotherapy for superficial transitional cell carcinoma of the urinary bladder is the instillation of bacillus Calmette-Guérin (BCG), proceeding from an attenuated strain of Mycobacterium bovis. In up to 40% of cases, its instillation is associated with significantly elevated prostate-specific antigen (PSA) levels. In these cases, prostate biopsy should be withheld for 3 months and PSA should be monitored. Bacillary prostatitis is a rare occurrence in patients treated with intravesical BCG immunotherapy. Although symptomatic bacillary prostatitis is even rarer, it is the worst type of this condition. The aims of this study are to report a case of bacillary prostatitis as a rare adverse effect of intravesical BCG immunotherapy and to make a theoretical review about how to manage this complication. A 58-year-old man, former smoker, underwent a transurethral resection of the bladder in February 2004 because of a papillary transitional cell carcinoma of the bladder (pT1G2N0M0). After surgery, BCG instillation therapy was given in a total of 15 instillations, the last one in March 2007. In the last 3 months of therapy, until May 2007, a progressive increase in his PSA level was registered, and he underwent a prostate biopsy revealing granulomatous prostatitis of bacillary etiology. The semen culture was positive for M. bovis. After 3 months of a two-drug (isoniazid and rifampin) antituberculous regimen, the semen culture became negative and the PSA level decreased. The early identification of intravesical BCG immunotherapy complications allows their effective treatment. However, when a histological diagnosis of asymptomatic granulomatous prostatitis is made, the execution and type of treatment are controversial

The NAD+-dependent deacetylase SIRT2 attenuates oxidative stress and mitochondrial dysfunction and improves insulin sensitivity in hepatocytes

Funding Information: European Regional Development Fund (ERDF), Centro 2020 Regional Operational Programme (CENTRO-01-0145-FEDER-000012: HealthyAging2020); COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation and Portuguese national funds via FCT – Fundação para a Ciência e a Tecnologia (POCI-01-0145-FEDER-007440, SFRH/BPD/109347/ 2015 to R.M.O., SFRH/BD/86655/2012 to L.N. and SFRH/BPD/ 111815/2015 to P.G.); FLAD Life Science 2020 Grant to A.C.R.; European Molecular Biology Organization (EMBO Installation Grant to T.F.O.); DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB) to T.F.O.Insulin resistance is a major predictor of the development of metabolic disorders. Sirtuins (SIRTs) have emerged as potential targets that can be manipulated to counteract age-related diseases, including type 2 diabetes. SIRT2 has been recently shown to exert important metabolic effects, but whether SIRT2 regulates insulin sensitivity in hepatocytes is currently unknown. The aim of this study is to investigate this possibility and to elucidate underlying molecular mechanisms. Here, we show that SIRT2 is downregulated in insulin-resistant hepatocytes and livers, and this was accompanied by increased generation of reactive oxygen species, activation of stress-sensitive ERK1/2 kinase, and mitochondrial dysfunction. Conversely, SIRT2 overexpression in insulin-resistant hepatocytes improved insulin sensitivity, mitigated reactive oxygen species production and ameliorated mitochondrial dysfunction. Further analysis revealed a reestablishment of mitochondrial morphology, with a higher number of elongated mitochondria rather than fragmented mitochondria instigated by insulin resistance. Mechanistically, SIRT2 was able to increase fusion-related protein Mfn2 and decrease mitochondrial-associated Drp1. SIRT2 also attenuated the downregulation of TFAM, a key mtDNA-associated protein, contributing to the increase in mitochondrial mass. Importantly, we found that SIRT2 expression in PBMCs of human subjects was negatively correlated with obesity and insulin resistance. These results suggest a novel function for hepatic SIRT2 in the regulation of insulin sensitivity and raise the possibility that SIRT2 activators may offer novel opportunities for preventing or treating insulin resistance and type 2 diabetes.publishersversionpublishe

The NAD+-dependent deacetylase SIRT2 attenuates oxidative stress and mitochondrial dysfunction and improves insulin sensitivity in hepatocytes

Insulin resistance is a major predictor of the development of metabolic disorders. Sirtuins (SIRTs) have emerged as potential targets that can be manipulated to counteract age-related diseases, including type 2 diabetes. SIRT2 has been recently shown to exert important metabolic effects, but whether SIRT2 regulates insulin sensitivity in hepatocytes is currently unknown. The aim of this study is to investigate this possibility and to elucidate underlying molecular mechanisms. Here, we show that SIRT2 is downregulated in insulin-resistant hepatocytes and livers, and this was accompanied by increased generation of reactive oxygen species, activation of stress-sensitive ERK1/2 kinase, and mitochondrial dysfunction. Conversely, SIRT2 overexpression in insulin-resistant hepatocytes improved insulin sensitivity, mitigated reactive oxygen species production and ameliorated mitochondrial dysfunction. Further analysis revealed a reestablishment of mitochondrial morphology, with a higher number of elongated mitochondria rather than fragmented mitochondria instigated by insulin resistance. Mechanistically, SIRT2 was able to increase fusion-related protein Mfn2 and decrease mitochondrial-associated Drp1. SIRT2 also attenuated the downregulation of TFAM, a key mtDNA-associated protein, contributing to the increase in mitochondrial mass. Importantly, we found that SIRT2 expression in PBMCs of human subjects was negatively correlated with obesity and insulin resistance. These results suggest a novel function for hepatic SIRT2 in the regulation of insulin sensitivity and raise the possibility that SIRT2 activators may offer novel opportunities for preventing or treating insulin resistance and type 2 diabetes.European Regional Development Fund (ERDF), Centro 2020 Regional Operational Programme (CENTRO-01-0145-FEDER-000012: HealthyAging2020); COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation and Portuguese national funds via FCT – Fundação para a Ciência e a Tecnologia (POCI-01-0145-FEDER-007440, SFRH/BPD/109347/2015 to R.M.O., SFRH/BD/86655/2012 to L.N. and SFRH/BPD/111815/2015 to P.G.); FLAD Life Science 2020 Grant to A.C.R.; European Molecular Biology Organization (EMBO Installation Grant to T.F.O.); DFG Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB) to T.F.O

Novel organotin-PTA complexes supported on mesoporous carbon materials as recyclable catalysts for solvent-free cyanosilylation of aldehydes

The work was also funded by national funds through FCT, under the Scientific Employment Stimulus-Institutional Call (CEEC-INST/00102/2018). AGM is grateful to Associação do Instituto Superior Técnico para a Investigação e Desenvolvimento ( IST-ID ) for his post-doctoral fellowship through grant no. BL133/2021-IST-ID . AP and AMF are grateful to FCT and Instituto Superior Técnico (IST), Portugal through DL/57/2017 (Contract no. IST-ID/197/2019 and IST-ID/131/2018). This publication is also supported by the RUDN University Strategic Academic Leadership Program (recipient AJLP, preparation). The authors also acknowledge the Portuguese NMR Network (IST-UL Centre) for access to the NMR facility. Publisher Copyright: © 2023 Elsevier B.V.New organotin compounds with general formula [(PTA-CH2-C6H4-p-COO)SnR3]Br (where R is Me for 3 and Ph for 4; PTA = 1,3,5-triaza-7-phosphaadamantane), bearing the methylene benzoate PTA derivative, were synthesized through a mild two-step process. The compounds were characterized by Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, elemental analysis and nuclear magnetic resonance spectroscopy (NMR). They were heterogenized on commercially available activated carbon (AC) and multi-walled carbon nanotubes (CNT), as well as on their chemically modified analogues. The obtained materials were characterized by scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. Complex 3 supported on activated carbon (3-AC) was found to be an active and recyclable catalyst for the cyanosilylation of several aromatic and aliphatic aldehydes. Using 3-AC with a low loading of 0.1 mol% several substrates were quantitatively converted, within just 5 min at 50 °C and under microwave irradiation in solvent-free conditions. Multinuclear NMR analysis suggested a mechanism that potentially involves a double activation process, where the nucleophilic phosphorus at the PTA derivative acts as a Lewis base and the Sn(IV) metal centre as a Lewis acid.publishersversionpublishe

Recovery of carotenoids from brown seaweeds using aqueous solutions of surface-active ionic liquids and anionic surfactants

Carotenoids are lipophilic compounds and their production is one of the most challenging, yet rewarding, activities in algal biotechnology. Some carotenoids (fucoxanthin included) have antioxidant activity and many studies have confirmed their health benefits. Fucoxanthin is considered as one of the most important intracellular active metabolites present in brown macroalgae. In this work, aqueous solutions of different surface-active ionic liquids and anionic surfactants were evaluated for the carotenoids extraction. Aqueous solutions of sodium dodecyl sulfate were selected as the media with the best extractive performance. For the best solvent, the solid-liquid ratio, concentration, and time of extraction were the conditions optimized and the maximum yield of extraction of carotenoids attained found to be between 2.57 ± 0.26 mgcarotenoids/gdried mass and 3.31 ± 0.02 mgcarotenoids/gdried mass, depending of the algae batch used. This said, this work proposed an efficient water-based process of carotenoids extraction, for both dried (more 37.4% of carotenoids extracted) and wet (more 30.2% of carotenoids extracted) biomass matricespublishe

Luminescent electrochromic devices for smart windows of energy-efficient buildings

To address the challenges of the next generation of smart windows for energy-efficient buildings, new electrochromic devices (ECDs) are introduced. These include indium molybdenum oxide (IMO), a conducting oxide transparent in the near-infrared (NIR) region, and a NIR-emitting electrolyte. The novel electrolytes are based on a sol-gel-derived di-urethane cross-linked siloxane-based host structure, including short chains of poly (ε-caprolactone) (PCL(530) (where 530 represents the average molecular weight in g mol−1). This hybrid framework was doped with a combination of either, lithium triflate (LiTrif) and erbium triflate (ErTrif3), or LiTrif and bisaquatris (thenoyltrifluoroacetonate) erbium (III) ([Er(tta)3(H2O)2]). The ECD@LiTrif-[Er(tta)3(H2O)2] device presents a typical Er3+ NIR emission around 1550 nm. The figures of merit of these devices are high cycling stability, good reversibility, and unusually high coloration efficiency (CE = ΔOD/ΔQ, where Q is the inserted/de-inserted charge density). CE values of −8824/+6569 cm2 C−1 and −8243/+5200 cm2 C−1 were achieved at 555 nm on the 400th cycle, for ECD@LiTrif-ErTrif3 and ECD@LiTrif-[Er(tta)3(H2O)2], respectively.This research was funded by National Funds through the Foundation for Science and Technology (FCT) and by FEDER funds through the POCI-COMPETE 2020, Operational Programme Competitiveness and Internationalisation in Axis I: Strengthening research, technological development and innovation (FCT Ref. UID/QUI/00616/2013, POCI-01-0145-FEDER-007491, FCT Ref. UID/Multi/00709/2013), and LUMECD (POCI-01-0145-FEDER-016884 and PTDC/CTM-NAN/0956/2014).info:eu-repo/semantics/publishedVersio

Lipophilic Fraction of Cultivated Bifurcaria bifurcata R. Ross: Detailed Composition and In Vitro Prospection of Current Challenging Bioactive Properties

Macroalgae have been seen as an alternative source of molecules with promising bioactivities to use in the prevention and treatment of current lifestyle diseases. In this vein, the lipophilic fraction of short-term (three weeks) cultivated Bifurcaria bifurcata was characterized in detail by gas chromatography–mass spectrometry (GC-MS). B. bifurcata dichloromethane extract was composed mainly by diterpenes (1892.78 ± 133.97 mg kg−1 dry weight (DW)), followed by fatty acids, both saturated (550.35 ± 15.67 mg kg−1 DW) and unsaturated (397.06 ± 18.44 mg kg−1 DW). Considerable amounts of sterols, namely fucosterol (317.68 ± 26.11 mg kg−1 DW) were also found. In vitro tests demonstrated that the B. bifurcata lipophilic extract show antioxidant, anti-inflammatory and antibacterial activities (against both Gram-positive and Gram-negative bacteria), using low extract concentrations (in the order of µg mL−1). Enhancement of antibiotic activity of drug families of major clinical importance was observed by the use of B. bifurcata extract. This enhancement of antibiotic activity depends on the microbial strain and on the antibiotic. This work represents the first detailed phytochemical study of the lipophilic extract of B. bifurcata and is, therefore, an important contribution for the valorization of B. bifurcata macroalgae, with promising applications in functional foods, nutraceutical, cosmetic and biomedical fields