Public engagement projects developed by university-based academics tend to focus on specific academic topics. Yet, the problems and topics that our audiences want to engage with are broad, ...challenging, and can't be explained or solved by a single academic subject or expertise. In this article, we capitalise on our experience working with academics at the University of Oxford, and a workshop for public engagement professionals that we co-organised with the National Coordinating Centre for Public Engagement, to advocate for a novel approach: interdisciplinary public engagement (public engagement projects that bring together academics from several academic disciplines). We consider the potential benefits and the challenges of this approach and provide examples of how it is starting to be explored.
Centrosomes comprise a pair of centrioles surrounded by pericentriolar material (PCM). The PCM expands dramatically as cells enter mitosis, but it is unclear how this occurs. In this study, we show ...that the centriole protein Asl initiates the recruitment of DSpd-2 and Cnn to mother centrioles; both proteins then assemble into co-dependent scaffold-like structures that spread outwards from the mother centriole and recruit most, if not all, other PCM components. In the absence of either DSpd-2 or Cnn, mitotic PCM assembly is diminished; in the absence of both proteins, it appears to be abolished. We show that DSpd-2 helps incorporate Cnn into the PCM and that Cnn then helps maintain DSpd-2 within the PCM, creating a positive feedback loop that promotes robust PCM expansion around the mother centriole during mitosis. These observations suggest a surprisingly simple mechanism of mitotic PCM assembly in flies.
Centriole assembly requires a small number of conserved proteins. The precise pathway of centriole assembly has been difficult to study, as the lack of any one of the core assembly proteins-Plk4, ...Ana2/STIL, Sas-6, Sas-4/CPAP or Asl/Cep152-leads to the absence of centrioles. Here we use Sas-6/Ana2 Particles (SAPs) as a new model to probe the pathway of centriole and centrosome assembly. SAPs form in Drosophila eggs/embryos when Sas-6 and Ana2 are overexpressed. SAP assembly requires Sas-4, but not Plk4, while Asl helps to initiate SAP assembly, but is not required for SAP growth. Although not centrioles, SAPs recruit and organize many centriole and centrosome components, nucleate microtubules, organise actin structures and compete with endogenous centrosomes to form mitotic spindle poles. SAPs require Asl/Cep152 to efficiently recruit pericentriolar material (PCM), but Spd-2/Cep192 can promote some PCM assembly independently of Asl/Cep152. These observations provide new insights into the pathways of centriole and centrosome assembly.
Centriole assembly requires a small number of conserved proteins. The precise pathway of centriole assembly has been difficult to study, as the lack of any one of the core assembly proteins Plk4, ...Ana2 (the homologue of mammalian STIL), Sas-6, Sas-4 (mammalian CPAP) or Asl (mammalian Cep152) leads to the absence of centrioles. Here, we use Sas-6 and Ana2 particles (SAPs) as a new model to probe the pathway of centriole and centrosome assembly. SAPs form in
eggs or embryos when Sas-6 and Ana2 are overexpressed. SAP assembly requires Sas-4, but not Plk4, whereas Asl helps to initiate SAP assembly but is not required for SAP growth. Although not centrioles, SAPs recruit and organise many centriole and centrosome components, nucleate microtubules, organise actin structures and compete with endogenous centrosomes to form mitotic spindle poles. SAPs require Asl to efficiently recruit pericentriolar material (PCM), but Spd-2 (the homologue of mammalian Cep192) can promote some PCM assembly independently of Asl. These observations provide new insights into the pathways of centriole and centrosome assembly.
Abstract The cationic lipid GL67A is one of the more efficient non-viral gene transfer agents (GTAs) for the lungs, and is currently being evaluated in an extensive clinical trial programme for ...cystic fibrosis gene therapy. Despite conferring significant expression of vector-specific mRNA following transfection of differentiated human airway cells cultured on air liquid interfaces (ALI) cultures and nebulisation into sheep lung in vivo we were unable to detect robust levels of the standard reporter gene Firefly luciferase (FLuc). Recently a novel secreted luciferase isolated from Gaussia princeps (GLuc) has been described. Here, we show that (1) GLuc is a more sensitive reporter gene and offers significant advantages over the traditionally used FLuc in pre-clinical models for lung gene transfer that are difficult to transfect, (2) GL67A-mediated gene transfection leads to significant production of recombinant protein in these models, (3) promoter activity in ALI cultures mimics published in vivo data and these cultures may, therefore, be suitable to characterise promoter activity in a human ex vivo airway model and (4) detection of GLuc in large animal broncho-alveolar lavage fluid and serum facilitates assessment of duration of gene expression after gene transfer to the lungs. In summary, we have shown here that GLuc is a sensitive reporter gene and is particularly useful for monitoring gene transfer in difficult to transfect models of the airway and lung. This has allowed us to validate that GL67A, which is currently in clinical use, can generate significant amounts of recombinant protein in fully differentiated human air liquid interface cultures and the ovine lung in vivo.
Aiming at the enhancement of food products' nutritional and health value, the incorporation of nutraceuticals has attracted increasing interest in the last years. However, they often exhibit low ...water solubility and stability, limiting their direct incorporation into food products. Also, they show very low bioavailability due to limited bioaccessibility, poor absorption and/or chemical transformation within the gastrointestinal tract. This renders their health benefits extremely difficult to be realized by the consumers.
In the present review the recent innovations regarding the formulation and design of bio-based micro and nano-delivery systems to encapsulate nutraceuticals is discussed; it also gives an overview of the challenges associated to their development; and highlights some strategies to enhance nutraceuticals' bioavailability. An insight about delivery systems' potential toxicity (in particular at nano-scale) is also provided.
Recent developments in the design of bio-based delivery systems offer the possibility of stabilizing and enhancing nutraceuticals' functionality within food products. In fact, different strategies can be used to enhance nutraceuticals' bioavailability: i) nano-delivery systems, besides showing a huge potential for the protection of valuable nutraceuticals during food processing/digestion, can be used to increase their bioavailability; ii) absorption enhancement technologies have been successfully used to increase nutraceuticals' membrane permeation; and iii) excipient foods have been shown to improve nutraceuticals' biological activity. However, the application of these enabling technologies to food is hindered by very pertinent issues that can be summarized in the effective preservation/maximization of the nutraceuticals' bioactivity and safety, once inside the human body.
•Delivery systems allow nutraceuticals' protection and their incorporation in foods.•Bio-based delivery systems can be specifically designed to enhance nutraceuticals' bioavailability.•Bioavailability enhancement strategies include nano-delivery systems, absorption enhancers and excipient foods.•It is crucial to evaluate the safety of nano-delivery systems in food.•Development of delivery systems that provide nutraceuticals' greatest functionality and safety remains a challenge.
Ovarian cancer is the main cause of death from gynecological cancer, with its poor prognosis mainly related to late diagnosis and chemoresistance (acquired or intrinsic) to conventional alkylating ...and reactive oxygen species (ROS)-generating drugs. We and others reported that the availability of cysteine and glutathione (GSH) impacts the mechanisms of resistance to carboplatin in ovarian cancer. Different players in cysteine metabolism can be crucial in chemoresistance, such as the cystine/glutamate antiporter system Xc (xCT) and the H
S-synthesizing enzyme cystathionine β-synthase (CBS) in the pathway of cysteine catabolism. We hypothesized that, by disrupting cysteine metabolic flux, chemoresistance would be reverted. Since the xCT transporter is also able to take up selenium, we used selenium-containing chrysin (SeChry) as a plausible competitive inhibitor of xCT. For that, we tested the effects of SeChry on three different ovarian cancer cell lines (ES2, OVCAR3, and OVCAR8) and in two non-malignant cell lines (HaCaT and HK2). Results showed that, in addition to being highly cytotoxic, SeChry does not affect the uptake of cysteine, although it increases GSH depletion, indicating that SeChry might induce oxidative stress. However, enzymatic assays revealed an inhibitory effect of SeChry toward CBS, thus preventing production of the antioxidant H
S. Notably, our data showed that SeChry and folate-targeted polyurea dendrimer generation four (SeChry@PURE
-FA) nanoparticles increased the specificity for SeChry delivery to ovarian cancer cells, reducing significantly the toxicity against non-malignant cells. Collectively, our data support SeChry@PURE
-FA nanoparticles as a targeted strategy to improve ovarian cancer treatment, where GSH depletion and CBS inhibition underlie SeChry cytotoxicity.
•Cellulose extraction from grape pomace can be used to produce CNCs.•CNCs can be obtained through sequential acid hydrolysis and ultrasound processes.•Ultrasound led to needle-shaped CNCs and ...apparently more dispersed suspensions.•Caco-2 cells viability confirmed the non-toxicity of CNCs.
Cellulose nanocrystals (CNCs) were obtained from grape pomace through chemical and physical pretreatments. Bleached cellulose pulp was subjected to acid hydrolysis (AH) for 30 or 60 min and an ultrasound treatment to obtain CNCs (AH30S and AH60S). Compositional analyses of untreated (UGP) and pretreated (PGP) grape pomace showed the effectiveness of pretreatment in removing non-cellulosic components, recovering 80.1% cellulose in PGP (compared to 19.3% of UGP). Scanning and transmission electron microscopies were used to evaluate the CNCs morphology. AH in combination with ultrasound treatment led to needle-shaped structures and apparently more dispersed suspensions. Crystallinity index and thermal stability were studied by X-ray diffraction and thermogravimetric analysis, respectively. The AH60S sample presented high aspect ratio, crystallinity and thermal stability. CNCs toxicity was evaluated by exposing Caco-2 cells to CNCs suspension and evaluating their viability. Results showed that CNCs are non-toxic, opening the opportunity for their use on food and pharmaceutical applications.
Curcumin nanoemulsions stabilized by whey protein isolate were successfully developed using high-pressure homogenization. The effect of a chitosan layer deposition using the layer-by-layer technique ...on nanoemulsions' stability was evaluated during storage conditions, as well as during gastrointestinal tract passage. Lipids’ hydrolysis and curcumin bioaccessibility was assessed using a dynamic gastrointestinal model (simulating the stomach, duodenum, jejunum and ileum) and the cytotoxicity, cellular antioxidant activity and permeability analyses were carried out using Caco-2 cells. Results showed that both nanosystems were stable during one month of storage and at stomach pH conditions, whereas creaming and phase separation occurred at intestine pH conditions. The addition of a chitosan layer increased curcumin bioaccessibility, whereas cellular antioxidant activity studies revealed that nanoemulsions and multilayer nanoemulsions exhibited 9 and 10 times higher antioxidant capacity at the cellular level, respectively, when compared to free curcumin. Permeability assays showed that the use of a chitosan layer significantly increased the apparent permeability coefficient of curcumin through Caco-2 cells by 1.55-folds.
•Curcumin nanosystems increase curcumin bioaccessibility.•Nanosystems showed higher cellular antioxidant capacity than free curcumin.•Chitosan can enhance curcumin apparent permeability coefficient by 1.55-fold.•Transcellular and paracellular pathways may exist at the same time.
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