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Nucleic acid nanoparticles (NANPs) have become powerful new platforms as therapeutic and diagnostic tools due to the innate biological ability of nucleic acids to identify target molecules or silence genes involved in disease pathways. However, the clinical application of NANPs has been limited by factors such as chemical instability, inefficient intracellular delivery, and the triggering of detrimental inflammatory responses following innate immune recognition of nucleic acids. Here, we have studied the effects of altering the chemical composition of a circumscribed panel of NANPs that share the same connectivity, shape, size, charge and sequences. We show that replacing RNA strands with either DNA or chemical analogs increases the enzymatic and thermodynamic stability of NANPs. Furthermore, we have found that such composition changes affect delivery efficiency and determine subcellular localization, effects that could permit the targeted delivery of NANP-based therapeutics and diagnostics. Importantly, we have determined that altering NANP composition can dictate the degree and mechanisms by which cell immune responses are initiated. While RNA NANPs trigger both TLR7 and RIG-I mediated cytokine and interferon production, DNA NANPs stimulate minimal immune activation. Importantly, incorporation of 2′F modifications abrogates RNA NANP activation of TLR7 but permits RIG-I dependent immune responses. Furthermore, 2′F modifications of DNA NANPs significantly enhances RIG-I mediated production of both proinflammatory cytokines and interferons. Collectively this indicates that off-target effects may be reduced and/or desirable immune responses evoked based upon NANPs modifications. Together, our studies show that NANP composition provides a simple way of controlling the immunostimulatory potential, and physicochemical and delivery characteristics, of such platforms.

There has been a surge of research on Home Children in the past several decades, as the phenomenon previously unknown to many came into the spotlight. However, much of the historical research has focused on either the psychological and physical impacts on the children at the hands of their new “families” (there were many reports of child abuse and neglect) or the ways they were saved from their poverty in Britain by being sent to the colonies. This article will put this existing historical research into conversation with theories of settler colonialism, considering Home Children as a tool of domestication for the social reproduction of Canadian white settler society, which was paired with the forced removal of Indigenous peoples from their lands. This analysis stems from and is intertwined with personal reflections on my own family history as a white settler woman descending from a Home Child to explore the gendered labour of social reproduction as a crucial pillar in creating and maintaining settler colonial Canada. Following Lorenzo Veracini’s argument that settler colonialism is a distinct structure that uses domestication as one of its key tenets and relies on its “regenerative capacity”, this paper will explore how British Home Children were a key component of settler colonialism in Canada and how this history has manifested in the current gendered, racialized, and classed politics of “settling”.

Background HIV+ donor (HIV D+) to HIV+ recipient (HIV R+) transplantation involves ethical considerations related to safety, consent, stigma, and privacy, which could be better understood through studying patients' actual experiences. Methods We interviewed kidney and liver transplant recipients enrolled in clinical trials evaluating HIV D+/R+ transplantation at 4 centers regarding their decision-making process, the informed consent process, and posttransplant experiences. Participants were interviewed at-transplant (≤3 wk after transplant), posttransplant (≥3 mo after transplant), or both time points. Interviews were analyzed thematically using constant comparison of inductive and deductive coding. Results We conducted 35 interviews with 22 recipients (15 at-transplant; 20 posttransplant; 13 both time points; 85% participation). Participants accepted HIV D+ organs because of perceived benefits and situational factors that increased their confidence in the trials and outweighed perceived clinical and social risks. Participants reported positive experiences with the consent process and the trial. Some described HIV-related stigma and emphasized the need for privacy; others believed HIV D+/R+ transplantation could help combat such stigma. There were some indications of possible therapeutic misestimation (overestimation of benefits or underestimation of risks of a study). Some participants believed that HIV+ transplant candidates were unable to receive HIV-noninfected donor organs. Conclusions Despite overall positive experiences, some ethical concerns remain that should be mitigated going forward. For instance, based on our findings, targeted education for HIV+ transplant candidates regarding available treatment options and for transplant teams regarding privacy and stigma concerns would be beneficial.

BackgroundAntibiotics are not recommended for treatment of acute uncomplicated bronchitis (AUB), but are often prescribed (85% of AUB visits within the Veterans Affairs nationally). This quality improvement project aimed to decrease antibiotic prescribing for AUB in community-based outpatient centres from 65% to MethodsFrom January to December 2018, community-based outpatient clinics’ 6 months’ average of prescribed antibiotics for AUB and upper respiratory infections was 63% (667 of 1054) and 64.6% (314 of 486) when reviewing the last 6 months. Seven plan–do–study–act (PDSA) cycles were implemented by an interprofessional antimicrobial stewardship team between January 2019 and March 2020. Balancing measures were a return patient phone call or visit within 4 weeks for the same complaint. Χ2 tests and statistical process control charts using Western Electric rules were used to analyse intervention data.ResultsThe AUB antibiotic prescribing rate decreased from 64.6% (314 of 486) in the 6 months prior to the intervention to 36.8% (154 of 418) in the final 6 months of the intervention. No change was seen in balancing measures. The largest reduction in antibiotic prescribing was seen after implementation of PDSA 6 in which 14 high prescribers were identified and targeted for individualised reviews of encounters of patients with AUB with an antimicrobial steward.ConclusionsOperational implementation of successful stewardship interventions is challenging and differs from the traditional implementation study environment. As a nascent outpatient stewardship programme with limited resources and no additional intervention funding, we successfully reduced antibiotic prescribing from 64.6% to 36.8%, a reduction of 43% from baseline. The most success was seen with targeted education of high prescribers.

The unknown immune stimulation by nucleic acid nanoparticles (NANPs) has become one of the major impediments to a broad spectrum of clinical developments of this novel technology. Having evolved to defend against bacterial and viral nucleic acids, mammalian cells have established patterns of recognition that are also the pathways through which NANPs can be processed. Explorations into the immune stimulation brought about by a vast diversity of known NANPs have shown that variations in design correlate with variations in immune response. Therefore, as the mechanisms of stimulation are further elucidated, these trends are now being taken into account in the design phase to allow for development of NANPs that are tailored for controlled immune activation or quiescence.

Background 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is widely used in diagnostic cancer imaging. However, the use of 18F-FDG in PET-based imaging is limited by its specificity and sensitivity. In contrast, anti-TAG (tumor associated glycoprotein)-72 monoclonal antibodies are highly specific for binding to a variety of adenocarcinomas, including colorectal cancer. The aim of this preliminary study was to evaluate a complimentary determining region (CDR)-grafted humanized CH2-domain-deleted anti-TAG-72 monoclonal antibody (HuCC49deltaCH2), radiolabeled with iodine-124 (124I), as an antigen-directed and cancer-specific targeting agent for PET-based imaging. Methods HuCC49deltaCH2 was radiolabeled with 124I. Subcutaneous tumor implants of LS174T colon adenocarcinoma cells, which express TAG-72 antigen, were grown on athymic Nu/Nu nude mice as the xenograft model. Intravascular (i.v.) and intraperitoneal (i.p.) administration of 124I-HuCC49deltaCH2 was then evaluated in this xenograft mouse model at various time points from approximately 1 hour to 24 hours after injection using microPET imaging. This was compared to i.v. injection of 18F-FDG in the same xenograft mouse model using microPET imaging at 50 minutes after injection. Results At approximately 1 hour after i.v. injection, 124I-HuCC49deltaCH2 was distributed within the systemic circulation, while at approximately 1 hour after i.p. injection, 124I-HuCC49deltaCH2 was distributed within the peritoneal cavity. At time points from 18 hours to 24 hours after i.v. and i.p. injection, 124I-HuCC49deltaCH2 demonstrated a significantly increased level of specific localization to LS174T tumor implants (p = 0.001) when compared to the 1 hour images. In contrast, approximately 50 minutes after i.v. injection, 18F-FDG failed to demonstrate any increased level of specific localization to a LS174T tumor implant, but showed the propensity toward more nonspecific uptake within the heart, Harderian glands of the bony orbits of the eyes, brown fat of the posterior neck, kidneys, and bladder. Conclusions On microPET imaging, 124I-HuCC49deltaCH2 demonstrates an increased level of specific localization to tumor implants of LS174T colon adenocarcinoma cells in the xenograft mouse model on delayed imaging, while 18F-FDG failed to demonstrate this. The antigen-directed and cancer-specific 124I-radiolabled anti-TAG-72 monoclonal antibody conjugate, 124I-HuCC49deltaCH2, holds future potential for use in human clinical trials for preoperative, intraoperative, and postoperative PET-based imaging strategies, including fused-modality PET-based imaging platforms.

This study investigates cross-border collaboration between beef organisations in Australia and Singapore. It aims to identify factors impacting trust and technology diffusion by gauging gaps between expected importance and perceived performance rating of the factors. The research presents results of a survey comprising 69 beef organisations from Australia and Singapore. The research identifies critical gaps using two methods of analysis; validity analysis and performance gap analysis. Each method comprises two types of tests. The WarpPLS software is used to perform the validity analysis. Results indicate gaps in level of responsiveness. The research concludes that the success of cross-border collaboration between organisations in both Australia and Singapore can be better achieved through the establishment of information exchange relationships, rather than through the use of technology alone, and by ensuring compatibility between business partners.