"Access to healthcare is a human right": a constructivist study exploring the impact and potential of a hospital-community partnered COVID-19 community response team for Toronto homeless services and congregate living settings.

BACKGROUND: Individuals experiencing homelessness face unique physical and mental health challenges, increased morbidity, and premature mortality. COVID -19 creates a significant heightened risk for those living in congregate sheltering spaces. In March 2020, the COVID-19 Community Response Team formed at Women's College Hospital, to support Toronto shelters and congregate living sites to manage and prevent outbreaks of SARS-CoV-2 using a collaborative model of onsite mobile testing and infection prevention. From this, the Women's College COVID-19 vaccine program emerged, where 14 shelters were identified to co-design and support the administration of vaccine clinics within each shelter. This research seeks to evaluate the impact of this partnership model and its future potential in community-centered integrated care through three areas of inquiry: (1) vaccine program evaluation and lessons learned; (2) perceptions on hospital/community partnership; (3) opportunities to advance hospital-community partnerships. METHODS: Constructivist grounded theory was used to explore perceptions and experiences of this partnership from the voices of shelter administrators. Semi-structured interviews were conducted with administrators from 10 shelters using maximum variation purposive sampling. A constructivist-interpretive paradigm was used to determine coding and formation of themes: initial, focused, and theoretical. RESULTS: Data analysis revealed five main categories, 16 subcategories, and one core category. The core category "access to healthcare is a human right; understand our communities" emphasizes access to healthcare is a consistent barrier for the homeless population. The main categories revealed during a time of confusion, the hospital was seen as credible and trustworthy. However, the primary focus of many shelters lies in housing, and attention is often not placed on health resourcing, solidifying partnerships, accountability, and governance structures therein. Health advocacy, information sharing tables, formalized partnerships and educating health professionals were identified by shelter administrators as avenues to advance intersectoral relationship building. CONCLUSION: Hospital-community programs can alleviate some of the ongoing health concerns faced by shelters - during a time of COVID-19 or not. In preparation for future pandemics, access to care and cohesion within the health system requires the continuous engagement in relationship-building between hospitals and communities to support co-creation of innovative models of care, to promote health for all.

Controlling the release of peptide antimicrobial agents from surfaces.

Medical conditions are often exacerbated by the onset of infection caused by hospital dwelling bacteria such as Staphylococcus aureus. Antibiotics taken orally or intravenously can require large and frequent doses, further contributing to the sharp rise in resistant bacteria observed over the past several decades. These existing antibiotics are also often ineffective in preventing biofilm formation, a common cause of medical device failure. Local delivery of new therapeutic agents that do not allow bacterial resistance to occur, such as antimicrobial peptides, could alleviate many of the problems associated with current antibacterial treatments. By taking advantage of the versatility of layer-by-layer assembly of polymer thin films, ponericin G1, an antimicrobial peptide known to be highly active against S. aureus, was incorporated into a hydrolytically degradable polyelectrolyte multilayer film. Several film architectures were examined to obtain various drug loadings that ranged from 20 to 150 microg/cm2. Release was observed over approximately ten days, with varying release profiles, including burst as well as linear release. Results indicated that film-released peptide did not suffer any loss in activity against S. aureus and was able to inhibit bacteria attachment, a necessary step in preventing biofilm formation. Additionally, all films were found to be biocompatible with the relevant wound healing cells, NIH 3T3 fibroblasts and human umbilical vein endothelial cells. These films provide the level of control over drug loading and release kinetics required in medically relevant applications including coatings for implant materials and bandages, while eliminating susceptibility to bacterial resistance.

Polyelectrolyte multilayers for tunable release of antibiotics.

Polyelectrolyte multilayers incorporating gentamicin were fabricated using layer-by-layer deposition. The multilayers could be precisely tuned with regard to dosage, and release rate under aqueous physiological conditions could be controlled. The films were demonstrated efficacious against Staphylococcus aureus and nontoxic toward murine osteoblasts MC3T3. The films were made in a layer-by-layer process with a heterostructural architecture that represents a general strategy for incorporating charged small molecular species into polyelectrolyte multilayers without the need for any physical or chemical premodification, expanding the range of active species that can be delivered from these films while maintaining the ease of layer-by-layer fabrication process.

Controlling interlayer diffusion to achieve sustained, multiagent delivery from layer-by-layer thin films.

We present the fabrication of conformal, hydrolytically degradable thin films capable of administering sustained, multiagent release profiles. Films are constructed one molecular layer at a time by using the layer-by-layer, directed-deposition technique; the subsequent hydrolytic surface erosion of these systems results in the release of incorporated materials in a sequence that reflects their relative positions in the film. The position of each species is determined by its ability to diffuse throughout the film architecture, and, as such, the major focus of this work is to define strategies that physically block interlayer diffusion during assembly to create multicomponent, stratified films. By using a series of radiolabeled polyelectrolytes as experimental probes, we show that covalently crosslinked barriers can effectively block interlayer diffusion, leading to compartmentalized structures, although even very large numbers of ionically crosslinked (degradable or nondegradable) barrier layers cannot block interlayer diffusion. By using these principles, we designed degradable films capable of extended release as well as both parallel and serial multiagent release. The ability to fabricate multicomponent thin films with nanoscale resolution may lead to a host of new materials and applications.

Improvement of thermal contact resistance by carbon nanotubes and nanofibers.

Interfacial thermal resistance results of various nanotube and nanofiber coatings, prepared by chemical vapor deposition (CVD) methods, are reported at relatively low clamping pressures. The five types of samples examined include multi-walled and single-walled nanotubes growth by CVD, multi-walled nanotubes grown by plasma enhanced CVD (PECVD) and carbon nanofibers of differing aspect ratio grown by PECVD. Of the samples examined, only high aspect ratio nanofibers and thermally grown multi-walled nanotubes show an improvement in thermal contact resistance. The improvement is approximately a 60% lower thermal resistance than a bare Si-Cu interface and is comparable to that attained by commercially available thermal interface materials.