163 research outputs found
Particle-Stabilized Fluid-Fluid Interfaces: The Impact of Core Composition on Interfacial Structure
The encapsulation of small molecule drugs in nanomaterials has become an increasingly popular approach to the delivery of therapeutics. The use of emulsions as templates for the synthesis of drug impregnated nanomaterials is an exciting area of research, and a great deal of progress has been made in understanding the interfacial chemistry that is critical to controlling the physicochemical properties of both the encapsulated material and the templated material. For example, control of the interfacial tension between an oil and aqueous phase is a fundamental concern when designing drug delivery vehicles that are stabilized by particulate surfactants at the fluid interface. Particles in general are capable of self-assembly at a fluid interface, with a preference for one or the other of the phases, and much work has focussed on modification of the particle properties to optimize formation and stability of the emulsion. An issue arises however when a model, single oil system is translated into more complex, real-world scenarios, which are often multi-component, with the incorporation of charged active ingredients and other excipients. The result is potentially a huge change in the properties of the dispersed phase which can lead to a failure in the capability of particles to continue to stabilize the interface. In this mini-review, we will focus on two encapsulation strategies based on the selective deposition of particles or proteins on a fluid-fluid interface: virus-like particles and polymer microcapsules formed from particle-stabilized emulsion templates. The similarity between these colloidal systems lies in the fact that particulate entities are used to stabilize fluid cores. We will focus on those studies that have described the effect of subtle changes in core composition on the self-assembly of particles at the fluid-fluid interface and how this influences the resulting capsule structure
Bibliometric and scientometric analysis of PSMA-targeted radiotheranostics: knowledge mapping and global standing
PurposeBibliometric and scientometric analyses provide a structured approach to large amounts of data, enabling the prediction of research theme trends over time, the detection of shifts in the boundaries of disciplines, and the identification of the most productive countries, institutions and scholars. In the context of prostate-specific membrane antigen (PSMA)-targeted radiotheranostics, no bibliometric or scientometric analysis has been published thus far. Therefore, this study was conducted to identify key contributors to the literature, assess the global scientific production of related research, and possibly predict future development patterns.MethodsScientometrics and bibliometrics were utilized to analyze the current body of knowledge while tracking its evolution to support scientific decision-making comprehensively and systematically. Science mapping techniques were employed to visualize research activities. Two different tools, Tableau and VOSviewer, were utilized, with VOSviewer being deemed the most suitable for the research objectives. The Web of Science (WoS) was used as the principal database for the searches.ResultsThrough the search process over a period of 30 years (January 1993âJanuary 2023), 694 original studies in the English language were subjected to comprehensive analysis. By employing bibliometric and scientometric methods, multiple networks were created that mapped various concepts, such as publication trends, leading countries, cocitations, coauthorship among researchers and scientists, as well as coauthorship among organizations and funding agencies. This study revealed the evolutionary patterns, trends, outliers, and key players in the PSMA field, which enabled a more nuanced understanding of the research landscape.ConclusionThis research contributes to the enrichment of knowledge on PSMA-targeted radiotheranostics through detailed global bibliometric and scientometric analyses. It stresses the necessity for the development of communication platforms, the establishment of supportive infrastructures, and the implementation of proactive solutions to address emerging challenges. This study offers a significant resource for delineating effective strategies and identifying prominent funding bodies essential for continuous advancements in the field of PSMA-based diagnosis and therapy for prostate cancer. It is vital to sustain this momentum to ensure further progress in this pioneering area
A chimeric affinity tag for efficient expression and chromatographic purification of heterologous proteins from plants
The use of plants as expression hosts for recombinant proteins is an increasingly attractive option for the production of complex and challenging biopharmaceuticals. Tools are needed at present to marry recent developments in high-yielding gene vectors for heterologous expression with routine protein purification techniques. In this study, we designed the Cysta-tag, a new purification tag for immobilized metal affinity chromatography (IMAC) of plant-made proteins based on the protein-stabilizing fusion partner SlCYS8. We show that the Cysta-tag may be used to readily purify proteins under native conditions, and then be removed enzymatically to isolate the protein of interest. We also show that commonly used protease recognition sites for linking purification tags are differentially stable in leaves of the commonly used expression host Nicotiana benthamiana, with those linkers susceptible to cysteine proteases being less stable then serine protease-cleavable linkers. As an example, we describe a Cysta-tag experimental scheme for the one-step purification of a clinically useful protein, human Îą1-antitrypsin, transiently expressed in N. benthamiana. With potential applicability to the variety of chromatography formats commercially available for IMAC-based protein purification, the Cysta-tag provides a convenient means for the efficient and cost-effective purification of recombinant proteins from plant tissues.A Discovery grant from the Natural Science and Engineering Research Council (NSERC) of Canada to DM, and by an Australian Research Council (ARC) Discovery Early Career Research Award to FS (DE140101553).PJ was the recipient of an AgroPhytoSciences NSERCâFONCER scholarship and of a BMP graduate scholarship funded by NSERC, the Fonds de Recherche QuĂŠbec Nature et Technologies and our private research partner Medicago Inc.http://www.frontiersin.orgam2016Plant Production and Soil Scienc
DNA-origami-directed virus capsid polymorphism
Viral capsids can adopt various geometries, most iconically characterized by icosahedral or helical symmetries. Importantly, precise control over the size and shape of virus capsids would have advantages in the development of new vaccines and delivery systems. However, current tools to direct the assembly process in a programmable manner are exceedingly elusive. Here we introduce a modular approach by demonstrating DNA-origami-directed polymorphism of single-protein subunit capsids. We achieve control over the capsid shape, size and topology by employing user-defined DNA origami nanostructures as binding and assembly platforms, which are efficiently encapsulated within the capsid. Furthermore, the obtained viral capsid coatings can shield the encapsulated DNA origami from degradation. Our approach is, moreover, not limited to a single type of capsomers and can also be applied to RNAâDNA origami structures to pave way for next-generation cargo protection and targeting strategies.</p
Rapid Transient Production in Plants by Replicating and Non-Replicating Vectors Yields High Quality Functional Anti-HIV Antibody
Background: The capacity of plants and plant cells to produce large amounts of recombinant protein has been well established. Due to advantages in terms of speed and yield, attention has recently turned towards the use of transient expression systems, including viral vectors, to produce proteins of pharmaceutical interest in plants. However, the effects of such high level expression from viral vectors and concomitant effects on host cells may affect the quality of the recombinant product. Methodology/Principal Findings: To assess the quality of antibodies transiently expressed to high levels in plants, we have expressed and characterised the human anti-HIV monoclonal antibody, 2G12, using both replicating and non-replicating systems based on deleted versions of Cowpea mosaic virus (CPMV) RNA-2. The highest yield (approximately 100 mg/kg wet weight leaf tissue) of affinity purified 2G12 was obtained when the non-replicating CPMV-HT system was used and the antibody was retained in the endoplasmic reticulum (ER). Glycan analysis by mass-spectrometry showed that the glycosylation pattern was determined exclusively by whether the antibody was retained in the ER and did not depend on whether a replicating or non-replicating system was used. Characterisation of the binding and neutralisation properties of all the purified 2G12 variants from plants showed that these were generally similar to those of the Chinese hamster ovary (CHO) cell-produced 2G12. Conclusions: Overall, the results demonstrate that replicating and non-replicating CPMV-based vectors are able to direct the production of a recombinant IgG similar in activity to the CHO-produced control. Thus, a complex recombinant protein was produced with no apparent effect on its biochemical properties using either high-level expression or viral replication. The speed with which a recombinant pharmaceutical with excellent biochemical characteristics can be produced transiently in plants makes CPMV-based expression vectors an attractive option for biopharmaceutical development and production
Time intervals from first symptom to treatment of cancer: a cohort study of 2,212 newly diagnosed cancer patients
<p>Abstract</p> <p>Background</p> <p>Delay in diagnosis of cancer may worsen prognosis. The aim of this study is to explore patient-, general practitioner (GP)- and system-related delay in the interval from first cancer symptom to diagnosis and treatment, and to analyse the extent to which delays differ by cancer type.</p> <p>Methods</p> <p>Population-based cohort study conducted in 2004-05 in the County of Aarhus, Denmark (640,000 inhabitants). Data were collected from administrative registries and questionnaires completed by GPs on 2,212 cancer patients newly diagnosed during a 1-year period. Median delay (in days) with interquartile interval (IQI) was the main outcome measure.</p> <p>Results</p> <p>Median total delay was 98 days (IQI 57-168). Most of the total delay stemmed from patient (median 21 days (7-56)) and system delay (median 55 days (32-93)). Median GP delay was 0 (0-2) days. Total delay was shortest among patients with ovarian (median 60 days (45-112)) and breast cancer (median 65 days (39-106)) and longest among patients with prostate (median 130 days (89-254)) and bladder cancer (median 134 days (93-181)).</p> <p>Conclusion</p> <p>System delay accounted for a substantial part of the total delay experienced by cancer patients. This points to a need for shortening clinical pathways if possible. A long patient delay calls for research into patient awareness of cancer. For all delay components, special focus should be given to the 4<sup>th </sup>quartile of patients with the longest time intervals and we need research into the quality of the diagnostic work-up process. We found large variations in delay for different types of cancer. Improvements should therefore target both the population at large and the specific needs associated with individual cancer types and their symptoms.</p
The Barley Genome Sequence Assembly Reveals Three Additional Members of the <i>CslF </i>(1,3;1,4)-b-Glucan Synthase Gene Family
An important component of barley cell walls, particularly in the endosperm, is (1,3;1,4)-β-glucan, a polymer that has proven health benefits in humans and that influences processability in the brewing industry. Genes of the cellulose synthase-like (Csl) F gene family have been shown to be involved in (1,3;1,4)-β-glucan synthesis but many aspects of the biosynthesis are still unclear. Examination of the sequence assembly of the barley genome has revealed the presence of an additional three HvCslF genes (HvCslF11, HvCslF12 and HvCslF13) which may be involved in (1,3;1,4)-β-glucan synthesis. Transcripts of HvCslF11 and HvCslF12 mRNA were found in roots and young leaves, respectively. Transient expression of these genes in Nicotiana benthamiana resulted in phenotypic changes in the infiltrated leaves, although no authentic (1,3;1,4)-β-glucan was detected. Comparisons of the CslF gene families in cereals revealed evidence of intergenic recombination, gene duplications and translocation events. This significant divergence within the gene family might be related to multiple functions of (1,3;1,4)-β-glucans in the Poaceae. Emerging genomic and global expression data for barley and other cereals is a powerful resource for characterising the evolution and dynamics of complete gene families. In the case of the CslF gene family, the results will contribute to a more thorough understanding of carbohydrate metabolism in grass cell walls
âThey All Said You Could Come and Speak to Usâ:Patientsâ Expectations and Experiences of Help on an Acute Psychiatric Inpatient Ward
Acute psychiatric inpatient care forms an integral part of mental health services. Few studies have focussed on the patient experience of acute care. Research into patient experience is increasingly important to policy and service development processes. Knowledge of patient experiences facilitates the development of nursing practice. The aim of the study was to gain insight into the experience of being a patient on an acute inpatient psychiatric ward. Thirteen participants were recruited from the acute ward. Unstructured interviews were used to gather narrative data of their experiences. Holistic analysis of the narratives was informed by Gee's socio-linguistic theories that meaning is linked to narrative structure. Reading of the holistic analyses yielded themes of help, safety and power running across the participants' experiences. The patient experience was characterized by dissonance between expectation and experience, the search for a nurseâpatient relationship and the development of strategies to cope with being on the acute ward. This paper focuses on the theme of âHelpâ where participants describe their expectation that they will receive help through the development of relationships with the nurses, and their experience of the barriers to this. In response, participants developed strategies to support each other
Mental health service users' experiences of mental health care: an integrative literature review.
The aim of this integrative literature review was to identify mental health service users' experiences of services. The rationale for this review was based on the growing emphasis and requirements for health services to deliver care and support, which recognizes the preferences of individuals. Contemporary models of mental health care strive to promote inclusion and empowerment. This review seeks to add to our current understanding of how service users experience care and support in order to determine to what extent the principles of contemporary models of mental health care are embedded in practice. A robust search of Web of Science, the Cochrane Database, Science Direct, EBSCO host (Academic Search Complete, MEDLINE, CINAHL Plus Full-Text), PsycINFO, PsycARTICLES, Social Sciences Full Text and the United Kingdom and Ireland Reference Centre for data published between 1 January 2008 and 31 December 2012 was completed. The initial search retrieved 272609 papers. The authors used a staged approach and the application of predetermined inclusion/exclusion criteria, thus the numbers of papers for inclusion were reduced to 34. Data extraction, quality assessment and thematic analysis were completed for the included studies. Satisfaction with the mental health service was moderately good. However, accessing services could be difficult because of a lack of knowledge and the stigma surrounding mental health. Large surveys document moderate satisfaction ratings; however, feelings of fear regarding how services function and the lack of treatment choice remain. The main finding from this review is while people may express satisfaction with mental health services, there are still issues around three main themes: acknowledging a mental health problem and seeking help; building relationship through participation and care; and working towards continuity of care. Elements of the recovery model appear to be lacking in relation to user involvement, empowerment and decision making. There is a need for a fundamental shift in the context of the provider-service user relationship to fully facilitate service users' engagement in their care
Pictures have propositional content
Although philosophers of art and aesthetics regularly appeal to a notion of âpictorial contentâ, there is little agreement over its nature. The present paper argues that pictures have propositional contents. This conclusion is reached by considering a style of argument having to do with the phenomenon of negation intended to show that pictures must have some kind of non-propositional content. I first offer reasons for thinking that arguments of that type fail. Second, I show that when properly understood, such arguments can in fact be turned on their heads and shown to support the propositionalist position
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