Nanodelivery of nucleic acids

Funding: This work was supported by the European Research Council (ERC) Starting Grant (ERC-StG-2019-848325 to J. Conde) and the Fundação para a Ciência e a Tecnologia FCT Grant (PTDC/BTM-MAT/4738/2020 to J. Conde). J.S. acknowledges US National Institute of Health (NIH) grants (R01CA200900, R01HL156362 and R01HL159012), the US DoD PRCRP Idea Award with Special Focus (W81XWH1910482), the Lung Cancer Discovery Award from the American Lung Association and the Innovation Discovery Grants award from the Mass General Brigham. H.L., D.Y. and X.Z. were supported by the National Key R&D Program of China (no. 2020YFA0710700), the National Natural Science Foundation of China (nos 21991132, 52003264, 52021002 and 52033010) and the Fundamental Research Funds for the Central Universities (no. WK2060000027).There is growing need for a safe, efficient, specific and non-pathogenic means for delivery of gene therapy materials. Nanomaterials for nucleic acid delivery offer an unprecedented opportunity to overcome these drawbacks; owing to their tunability with diverse physico-chemical properties, they can readily be functionalized with any type of biomolecules/moieties for selective targeting. Nucleic acid therapeutics such as antisense DNA, mRNA, small interfering RNA (siRNA) or microRNA (miRNA) have been widely explored to modulate DNA or RNA expression Strikingly, gene therapies combined with nanoscale delivery systems have broadened the therapeutic and biomedical applications of these molecules, such as bioanalysis, gene silencing, protein replacement and vaccines. Here, we overview how to design smart nucleic acid delivery methods, which provide functionality and efficacy in the layout of molecular diagnostics and therapeutic systems. It is crucial to outline some of the general design considerations of nucleic acid delivery nanoparticles, their extraordinary properties and the structure–function relationships of these nanomaterials with biological systems and diseased cells and tissues.publishersversionpublishe

58th Annual Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 58th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Breckenridge, Colorado, July 17-21, 2016

Biomarkers of Atherosclerosis A study of plasma and solid tissues from animal and human models using nuclear magnetic resonance (NMR) technology

Introduction: Current recommendations for surgical management of asymptomatic 50-99% carotid stenosis are guided by two factors, patient’s fitness for surgical intervention and the clinical/imaging features associated with an increased risk of late stroke. Despite the advances in imaging modalities and their ability to detect some features of plaque instability, full understanding the pathophysiology of plaque instability will allow early intervention in patients with high risk of developing stroke from the unstable plaque. To date, no serum or urine marker has been shown to predict plaque instability and the risk of future cerebrovascular events. Aims and methods: The aim of this study was to compare metabolic profiles of plasma and plaques from patients with symptomatic carotid stenosis undergoing endarterectomy, plasma and plaques from patients with symptomatic femoral stenosis, and plasma from patients without carotid or femoral disease (control). We also aim to compare plasma and solid tissues from mammalian model (mice), and further compare them to the human experiment. Nuclear magnetic resonance (NMR) spectroscopy will be used to analyse the metabolic profiles of plasma and plaques, and potentially identify predictive biomarkers of plaque instability. Animal experiment was carried out using 6 apolipoprotein E–deficient versus 6 control mice. For the human experiment, carotid and femoral plaques alongside plasma and urine samples were collected from 84 patients. NMR analysis was performed on all the samples and further analysis was done on the resulting spectra and correlating data. Results: The animal experiment showed weak models with inconclusive outcomes. Plasma human experiment also showed weak models and could not confidently establish certain metabolites as atherosclerotic biomarkers. However, similarities were observed between the animal and human models, and 3 metabolites (2-oxoglutarate, choline and taurine) were identified as potential biomarkers. In contrary, human solid tissue experiments have shown much stronger models and clearer results. Spectra gained from these experiments were the first to be described, with no comparable studies in the literature. The most notable finding is the possible effect of taurine on carotid plaques. Taurine signals have been observed in the animal (plasma and solid) as well as human plasma models in this study. Although, they were merely affecting the control groups. Conclusions: Identifying plaque instability in asymptomatic carotid disease was the centre of this study. Taurine’s strong influence on the metabolic profiling of carotid plaques raises the possibility of a potential biomarker of plaque instability. Further work is required regarding the histological examination of plaque sections. An objective assessment of the plaque instability will improve the study outcome and add a different aspect to the current results

Biomimetic Radical Chemistry and Applications

The enormous importance of free radical chemistry for a variety of biological events, including ageing and inflammation, has attracted a strong interest in understanding the related mechanistic steps at the molecular level. Modelling the free radical chemical reactivity of biological systems is an important research area. When studying free-radical-based chemical mechanisms, biomimetic chemistry and the design of established biomimetic models come into play to perform experiments in a controlled environment that is suitably designed to be in strict connection with cellular conditions. This Special Issue gives the reader a wide overview of biomimetic radical chemistry, where molecular mechanisms have been defined and molecular libraries of products are developed to also be used as traces for the discovery of some relevant biological processes. Several subjects are presented, with 12 articles and 6 reviews written by specialists in the fields of DNA, proteins, lipids, biotechnological applications, and bioinspired synthesis, having “free radicals” as a common denominator

Advanced fluorescence methodologies for the exploration of the nanoworld

Fluorescence spectroscopy and microscopy have emerged in the last few decades as robust methods to unravel the secrets of materials, their interactions and photophysical properties, on the nanoscale level. Confocal laser scanning microscopy (CLSM) is an important technique that utilizes the versatility of fluorescence as a tool to explore phenomena in the life- and material- sciences. In the scope of this thesis, a home built CLSM was upgraded and its advanced fluorescence method capabilities were used to investigate metal-organic frameworks (MOFs) and organic light emitting diodes (OLEDs). The interaction of differently functionalized MOF nanoparticles and serum proteins was studied by monitoring the fluorescence intensity fluctuations arising from the diffusion of fluorescently labeled nanoparticles through the small (~fL) confocal volume. This approach, known as the fluorescence correlation spectroscopy (FCS) analyzes the fluctuations of the recorded signal and extracts information regarding the rate of diffusion and the interaction between the MOFs and the proteins. In a second study, contrary to what was anticipated, rigid MOFs showed that a bulky linker was able to post-synthetically replace the organic likers of the original framework. Investigating the linker exchange via fluorescence imaging, combining the intensity and lifetime information, a new post synthetic linker exchange (PSE) mechanism in rigid MOFs was established. These studies show the versatility of utilizing CLSM measurements for FCS and fluorescence lifetime imaging microscopy (FLIM). The FLIM approach is a useful technique that relates the spatial variations in lifetime with the morphology of the examined structures. Investigating crystals and crystal-like luminescent structures via FLIM combined with the Hirshfeld surface (HS) analysis, provides information regarding the intermolecular interactions, structural-photophysical relationships could be established. Employing this tool on luminescent materials such as potential OLEDs structures provided new insights regarding their emissive properties, which is important for display and lighting technologies. Another application of fluorescence lifetime, via fluorescence spectroscopy, was employed to investigate the active center of a europium-dependent methanol dehydrogenase enzyme (Eu-MDH). Simultaneous measurements of the fluorescent cofactor and Eu metal ion, present in the MDH active center, showed their proximity to one another and provided a tool to characterize their photophysical behavior. Overall, utilizing the strengths of the upgraded CLSM, capable of the fluorescence methods presented within the scope of this thesis, elucidates a vast of relevant nanostructure properties especially in the field of material science

56th Annual Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 56th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Copper Mountain, Colorado, July 13-17, 2014