Pharyngeal adaptation to bolus properties in patients with Parkinson's disease.

PURPOSE: Dysphagia is common in people with Parkinson's disease (PD). Yet, literature describing swallow function in PD using high-resolution manometry is limited. This study explored swallowing pressure metrics for varied bolus conditions in people with PD. METHOD: A solid-state unidirectional catheter was used to acquire manometric data for triplicate swallows (5 ml, 10 ml, 20 ml; IDDSI 0, 2 & 4). Penetration-aspiration severity was rated during videofluoroscopy. Patient-reported measures included PDQ-8: Parkinson's Disease Questionnaire-8 and EAT-10: Eating Assessment Tool-10. Quantitative manometric swallow analysis was completed through Swallow Gateway™. Metrics were compared to published normative values and generalized linear model tests explored modulatory effects. RESULTS: 21 participants (76% male; mean age 69.6 years, SD 7.1) with mild-moderate severity PD were studied. Two patients (9%) aspirated for single bolus thin liquid and paste trials and 15 patients (73%) scored > 3 EAT-10. Standardized PDQ-8 scores correlated with EAT-10 (p < 0.05). Abnormality in UES relaxation and distension was demonstrated by high UES integrated relaxation pressure and low UES maximum admittance (UES MaxAdm) values across varied bolus conditions. Participants demonstrated abnormally elevated pharyngeal contractility and increased post-swallow upper-esophageal sphincter (UES) contractility for thinner liquid trials. Alterations in volume and viscosity had significant effects on the bolus timing metric-distention to contraction latency. UES peak pressure measures were altered in relation to bolus viscosity. CONCLUSION: This study identifies early pharyngoesophageal contractile changes in relation to bolus volume and viscosity in PD patients, associated with subtle deterioration of self-reported swallow scores. Manometric evaluation may offer insight into PD-related swallowing changes and help optimize diagnostics and treatment planning.

Engineering Magnetic Nanoclusters for Highly Efficient Heating in Radio-Frequency Nanowarming.

Effective thawing of cryopreserved samples requires rapid and uniform heating. This is achievable through nanowarming, an approach that heats magnetic nanoparticles by using alternating magnetic fields. Here we demonstrate the synthesis and surface modification of magnetic nanoclusters for efficient nanowarming. Magnetite (Fe3O4) nanoclusters with an optimal diameter of 58 nm exhibit a high specific absorption rate of 1499 W/g Fe under an alternating magnetic field at 43 kA/m and 413 kHz, more than twice that of commercial iron oxide cores used in prior nanowarming studies. Surface modification with a permeable resorcinol-formaldehyde resin (RFR) polymer layer significantly enhances their colloidal stability in complex cryoprotective solutions, while maintaining their excellent heating capacity. The Fe3O4@RFR nanoparticles achieved a high average heating rate of 175 °C/min in cryopreserved samples at a concentration of 10 mg Fe/mL and were successfully applied in nanowarming porcine iliac arteries, highlighting their potential for enhancing the efficacy of cryopreservation.

A Low-Cost, Tabletop LOD-EPR System for Nondestructive Quantification of Iron Oxide Nanoparticles in Tissues.

Iron oxide nanoparticles (IONPs) have wide utility in applications from drug delivery to the rewarming of cryopreserved tissues. Due to the complex behavior of IONPs (e.g., uneven particle distribution and aggregation), further developments and clinical translation can be accelerated by having access to a noninvasive method for tissue IONP quantification. Currently, there is no low-cost method to nondestructively track IONPs in tissues across a wide range of concentrations. This work describes the performance of a low-cost, tabletop, longitudinally detected electron paramagnetic resonance (LOD-EPR) system to address this issue in the field of cryopreservation, which utilizes IONPs for rewarming of rat kidneys. A low-cost LOD-EPR system is realized via simultaneous transmit and receive using MHz continuous-wave transverse excitation with kHz modulation, which is longitudinally detected at the modulation frequency to provide both geometric and frequency isolation. The accuracy of LOD-EPR for IONP quantification is compared with NMR relaxometry. Solution measurements show excellent linearity (R2 > 0.99) versus Fe concentration for both measurements on EMG308 (a commercial nanoparticle), silica-coated EMG308, and PEG-coated EMG308 in water. The LOD-EPR signal intensity and NMR longitudinal relaxation rate constant (R1) of water are affected by particle coating, solution viscosity, and particle aggregation. R1 remains linear but with a reduced slope when in cryoprotective agent (CPA) solution, whereas the LOD-EPR signal is relatively insensitive to this. R1 does not correlate well with Fe concentration in rat kidney sections (R2 = 0.3487), while LOD-EPR does (R2 = 0.8276), with a linear regression closely matching that observed in solution and CPA.

A Review of In Vitro and In Silico Swallowing Simulators: Design and Applications.

Swallowing is a primary and complex behaviour that transports food and drink from the oral cavity, through the pharynx and oesophagus, into the stomach at an appropriate rate and speed. To understand this sophisticated behaviour, a tremendous amount of research has been carried out by utilising the in vivo approach, which is often challenging to perform, poses a risk to the subjects if interventions are undertaken and are seldom able to control for confounding factors. In contrast, in silico (computational) and in vitro (instrumental) methods offer an alternate insight into the process of the human swallowing system. However, the appropriateness of the design and application of these methods have not been formally evaluated. The purpose of this review is to investigate and evaluate the state of the art of in vitro and in silico swallowing simulators, focusing on the evaluation of their mechanical or computational designs in comparison to the corresponding swallowing mechanisms during various phases of swallowing (oral phase, pharyngeal phase and esophageal phase). Additionally, the potential of the simulators is also discussed in various areas of applications, including the study of swallowing impairments, swallowing medications, food process design and dysphagia management. We also address current limitations and recommendations for the future development of existing simulators.

Investigating Parkinson's disease with dual high resolution pharyngeal manometry with impedance and videofluoroscopy.

PURPOSE: To characterize pharyngeal function in people with Parkinson's Disease using both high resolution impedance manometry (HRIM) and videofluoroscopy (VFSS) and to explore correlations between VFSS and HRIM metrics. METHODS: All participants received both VFSS and HRIM within 24 h-time window. A standard VFSS protocol (IDDSI 0: 1 mL, 3 mL, 20 mL, and 100 mL) was performed. A solid-state unidirectional catheter (36 pressure sensors) was used to acquire manometric data for triplicate swallows (IDDSI 0: 5 mL, 10 mL, 20 mL), quantitative swallow analysis was completed through Swallowtail™ and SwallowGateway™. Parameters were compared to published norms and statistical tests explored correlational associations (p < 0.05). RESULTS: Twenty-one participants (76% male; mean age 70 years, SD7.16) with mild-moderate severity PD were recruited with 73% reporting Eating Assessment Tool (EAT-10) scores ≥3 indicating swallow impairment. Compared to normal metrics, one third of participants had abnormally elevated hypopharyngeal contractile integral (HPCI), hypopharyngeal peak pressure, upper esophageal sphincter (UES) integrated relaxation pressure (UES IRP), and reduced UES maximum admittance. Five participants showed compromised swallow safety (Penetration-Aspiration Scale score ≥6). One third of participants had abnormal VFSS values for pharyngoesophageal segment (PES) opening duration, maximum PES opening distance, and maximum hyoid displacement measures. Some HRIM metrics had a strong correlation with pharyngeal VFSS measures (r > 0.60, p < 0.05). CONCLUSION: This study identifies early manometric signs of pharyngeal dysfunction in people with PD. The congruence of the VFSS and HRIM measures confirms the hypothesis of insidious early decline in swallow function in PD despite maintenance of airway safety (i.e., low aspiration rates).

The effectiveness of preoperative delirium prevention in intermediate to high-risk older surgical patients: A systematic review.

BACKGROUND: Few reviews have addressed delirium prevention among intermediate to high-risk older surgical patients. AIMS: To map preoperative delirium prevention interventions for older surgical patients at intermediate to high risk of developing delirium, assess outcomes and identify gaps in knowledge. DESIGN: Systematic narrative review of randomised controlled trials reported following the PRISMA checklist. METHODS: A systematic search was conducted of the literature published from 1990 to October 2022 in Medline, CINAHL and Ageline and of the grey literature in Google Scholar. Randomised controlled trials were retrieved that assessed the effectiveness of preoperative delirium prevention interventions for older surgical patients at intermediate to high risk of delirium. Data were extracted using a data extraction tool, and results were tabulated. Studies were assessed for bias using the Cochrane Collaboration Risk of Bias tool. RESULTS: Twenty-one studies met the selection criteria including N = 5096 participants. Two studies tested cognitive training, two studies tested fascia iliaca compartment block and one study assessed femoral nerve block. Ten studies tested prophylactic medications including methylprednisolone. Five studies investigated geriatric assessment and management. One study assessed transcutaneous electrical acupoint stimulation. In the two studies testing fascia iliaca compartment block, there was a reduction in postoperative delirium for orthopaedic patients. Methylprednisolone reduced postoperative delirium in orthopaedic patients and in those undergoing gastrointestinal surgery. Results of all other interventions on the occurrence of postoperative delirium and additional outcomes including the severity and duration of delirium were inconclusive. CONCLUSIONS: Despite the promising results for fascia iliaca compartment block and methylprednisolone, there is limited knowledge regarding evidence-based delirium prevention interventions. Most studies had small sample sizes indicating that the current evidence is exploratory. There is an urgent need for the funding and conduct of trials to test preventative interventions for older surgical patients at intermediate to high risk of developing delirium.

The Dubai Definition and Diagnostic Criteria of Laryngopharyngeal Reflux: The IFOS Consensus.

OBJECTIVE: The objective of this work was to gather an international consensus group to propose a global definition and diagnostic approach of laryngopharyngeal reflux (LPR) to guide primary care and specialist physicians in the management of LPR. METHODS: Forty-eight international experts (otolaryngologists, gastroenterologists, surgeons, and physiologists) were included in a modified Delphi process to revise 48 statements about definition, clinical presentation, and diagnostic approaches to LPR. Three voting rounds determined a consensus statement to be acceptable when 80% of experts agreed with a rating of at least 8/10. Votes were anonymous and the analyses of voting rounds were performed by an independent statistician. RESULTS: After the third round, 79.2% of statements (N = 38/48) were approved. LPR was defined as a disease of the upper aerodigestive tract resulting from the direct and/or indirect effects of gastroduodenal content reflux, inducing morphological and/or neurological changes in the upper aerodigestive tract. LPR is associated with recognized non-specific laryngeal and extra-laryngeal symptoms and signs that can be evaluated with validated patient-reported outcome questionnaires and clinical instruments. The hypopharyngeal-esophageal multichannel intraluminal impedance-pH testing can suggest the diagnosis of LPR when there is >1 acid, weakly acid or nonacid hypopharyngeal reflux event in 24 h. CONCLUSION: A global consensus definition for LPR is presented to improve detection and diagnosis of the disease for otolaryngologists, pulmonologists, gastroenterologists, surgeons, and primary care practitioners. The approved statements are offered to improve collaborative research by adopting common and validated diagnostic approaches to LPR. LEVEL OF EVIDENCE: 5 Laryngoscope, 134:1614-1624, 2024.

A Novel Quantitative Measure of Pharyngeal Shortening.

BACKGROUND: Little is known about pharyngeal shortening (PShort) during swallowing. This observational study measured PShort during swallowing in healthy adults and compared it to patients with swallowing impairments of different aetiologies. METHODS: 275 healthy volunteers (19-99 years) and 75 dysphagic patients (25 with head and neck cancer, 25 with Parkinson's, 25 with stroke) underwent videofluoroscopy. A novel quantitative measure of PShort for 1, 3, and 20 mL thin liquid barium and 3 mL paste boli was determined and compared across age, sex, bolus type and patient cohort. RESULTS: PShort ranged from 1.05 to 4.41 cm across bolus types with larger displacements for 20 mL (M: 2.52 cm) and paste (M: 2.43 cm) compared with 1 mL (M: 2.36 cm) and 3 mL (M: 2.41 cm). PShort correlated with sex, height, and cohort but not age. Inter-rater reliability for three raters was substantial (intraclass correlation >0.80). CONCLUSIONS: This novel fluoroscopic measure of PShort is reliable and demonstrates quantitative changes in vertical pharyngeal displacement in healthy and swallow-impaired adults related to sex, size, and bolus type. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:2121-2126, 2024.

A systematic review of behavioural therapies for improving swallow and cough function in Parkinson's disease.

Purpose: This systematic review evaluated the efficacy of therapeutic interventions on improving swallow, respiratory, and cough functions in Parkinson's disease (PD).Method: A PRISMA systematic search was implemented across six databases. We selected studies reporting pre- and post-assessment data on the efficacy of behavioural therapies with a swallow or respiratory/cough outcome, and excluded studies on medical/surgical treatments or single-session design. Cross-system outcomes across swallow, respiratory, and cough functions were explored. Cochrane's risk of bias tools were utilised to evaluate study quality.Result: Thirty-six articles were identified and further clustered into four treatment types: swallow related (n = 5), electromagnetic stimulation (n = 4), respiratory loading (n = 20), and voice loading (n = 7) therapies. The effects of some behavioural therapies were supported with high-quality evidence in improving specific swallow efficiency, respiratory pressure/volume, and cough measures. Only eleven studies were rated with a low risk of bias and the remaining studies failed to adequately describe blinding of assessors, missing data, treatment adherence, and imbalance assignment to groups.Conclusion: Behavioural therapies were diverse in nature and many treatments demonstrated broad cross-system outcome benefits across swallow, respiratory, and cough functions. Given the progressive nature of the condition, the focus of future trials should be evaluating follow-up therapy effects and larger patient populations, including those with more severe disease.

Informal carer support needs, facilitators and barriers in transitional care for older adults from hospital to home: A scoping review.

AIM: To synthesise evidence about informal carers' (carers) experience of their support needs, facilitators and barriers regarding transitional care of older adults with multimorbidity. BACKGROUND: Carers provide crucial support for older adults during care transitions. Although health practitioners are well positioned to support carers, system factors including limited healthcare resources can compromise the quality of care transitions. DESIGN: Scoping review. METHODS: Searches were undertaken of the published literature. Five databases were searched including MEDLINE, CINAHL, EMBASE, PsycINFO and the Cochrane Library. Two reviewers independently screened articles to identify relevant studies. Studies were retrieved from January 2000 to July 2022. Data were extracted and tabulated for study characteristics, support needs, facilitators and barriers. Key themes and patterns were synthesised across the studies. RESULTS: Eighteen studies including N = 3174 participants were retrieved. Most studies (n = 13) employed qualitative designs. Five studies used surveys. Carers reported their need to: be involved in coordinated discharge planning; advocate and be involved in decision-making; and receive community-based follow-up. Carers described facilitators and barriers in four themes: (1) relationships with the older adult and health practitioners, (2) being involved in coordinated discharge planning; (3) communication and information strategies; and (4) community-based follow-up. Synthesis of themes across all studies resulted in the identification of five areas of research: carers' health literacy; community-based care; carers' involvement in transitional care planning; inpatient and community health practitioners' communication skills; and culturally diverse carers' experiences. CONCLUSION AND RELEVANCE TO CLINICAL PRACTICE: The review highlights the importance of quality communication and relationships between carers, older adults, health practitioners and health organisations. Although information and education are important there is a need for further research to examine systems that support communication between carers, older adults and health practitioners and health literacy for all carers including culturally diverse carers.

Vitrification and nanowarming enable long-term organ cryopreservation and life-sustaining kidney transplantation in a rat model.

Banking cryopreserved organs could transform transplantation into a planned procedure that more equitably reaches patients regardless of geographical and time constraints. Previous organ cryopreservation attempts have failed primarily due to ice formation, but a promising alternative is vitrification, or the rapid cooling of organs to a stable, ice-free, glass-like state. However, rewarming of vitrified organs can similarly fail due to ice crystallization if rewarming is too slow or cracking from thermal stress if rewarming is not uniform. Here we use "nanowarming," which employs alternating magnetic fields to heat nanoparticles within the organ vasculature, to achieve both rapid and uniform warming, after which the nanoparticles are removed by perfusion. We show that vitrified kidneys can be cryogenically stored (up to 100 days) and successfully recovered by nanowarming to allow transplantation and restore life-sustaining full renal function in nephrectomized recipients in a male rat model. Scaling this technology may one day enable organ banking for improved transplantation.

Nurses' experience of managing adults living with multimorbidity: A qualitative study.

BACKGROUND: The number of adults living with two or more chronic conditions is increasing worldwide. Adults living with multimorbidity have complex physical, psychosocial and self-management care needs. AIM: This study aimed to describe Australian nurses' experience of care provision for adults living with multimorbidity, their perceived education needs and future opportunities for nurses in the management of multimorbidity. DESIGN: Qualitative exploratory. METHODS: Nurses providing care to adults living with multimorbidity in any setting were invited to take part in a semi-structured interview in August 2020. Twenty-four registered nurses took part in a semi-structured telephone interview. RESULTS: Three main themes were developed: (1) The care of adults living with multimorbidity requires skilled collaborative and holistic care; (2) nurses' practice in multimorbidity care is evolving; and (3) nurses value education and training in multimorbidity care. CONCLUSION: Nurses recognize the challenge and the need for change in the system to support them to respond to the increasing demands they face. IMPACT: The complexity and prevalence of multimorbidity creates challenges for a healthcare system configured to treat individual disease. Nurses are key in providing care for this population, but little is known about nurses' experiences and perceptions of their role. Nurses believe a person-centred approach is important to address the complex needs of adults living with multimorbidity. Nurses described their role as evolving in response to the growing demand for quality care and believed inter-professional approaches achieve the best outcomes for adults living with multimorbidity. The research has relevance for all healthcare providers seeking to provide effective care for adults living with multimorbidity. Understanding how best to equip and support the workforce to meet the issues and demands of managing the care of adults living with multimorbidity has the potential to improve patient outcomes. PATIENT OR PUBLIC CONTRIBUTION: There was no patient or public contribution. The study only concerned the providers of the service.

NMR Characterization of Polyethylene Glycol Conjugates for Nanoparticle Functionalization.

The molecular weight, purity, and functionalization of polyethylene glycols are often characterized by 1H NMR spectroscopy. Oft-forgotten, the typical 1H NMR pulse sequence is not 13C decoupled. Hence, for large polymers, the 13C coupled 1H peaks arising from the repeating units have integrations comparable to that of the 1H of the terminal groups. Ignoring this coupling leads to erroneous assignments. Once correctly assigned, these 13C coupled 1H peaks can be used to determine both the molecular weight of the polymer and the efficacy of conjugation of a terminal moiety more accurately than the uncoupled 1H of the repeating unit.

The American Broncho-Esophagological Association Position Statement on Swallowing Fluoroscopy.

OBJECTIVES: To develop an expert consensus statement on the clinical use of swallowing fluoroscopy in adults that reduces practice variation and identifies opportunities for quality improvement in the care of patients suffering from swallowing impairment. METHODOLOGY: A search strategist reviewed data sources (PubMed, Embase, Cochrane, Web of Science, Scopus) to use as evidence for an expert development group to compose statements focusing on areas of controversy regarding swallowing fluoroscopy. Candidate statements underwent two iterations of a modified Delphi protocol to reach consensus. RESULTS: A total of 2184 publications were identified for title and abstract review with 211 publications meeting the criteria for full text review. Of these, 148 articles were included for review. An additional 116 publications were also included after reviewing the references of the full text publications from the initial search. These 264 references guided the authors to develop 41 candidate statements in various categories. Forty statements encompassing patient selection, fluoroscopic study choice, radiation safety, clinical team dynamics, training requirements, videofluoroscopic swallow study and esophagram techniques, and interpretation of swallowing fluoroscopy met criteria for consensus. One statement on esophagram technique reached near-consensus. CONCLUSIONS: These 40 statements pertaining to the comprehensive use of swallowing fluoroscopy in adults can guide the development of best practices, improve quality and safety of care, and influence policy in both the outpatient and inpatient settings. The lack of consensus on some aspects of esophagram technique likely reflects gaps in knowledge and clinical practice variation and should be a target for future research. Laryngoscope, 133:255-268, 2023.

Best Practices in Treatment of Laryngopharyngeal Reflux Disease: A Multidisciplinary Modified Delphi Study.

BACKGROUND: Laryngopharyngeal reflux (LPR) is a common otolaryngologic diagnosis. Treatment of presumed LPR remains challenging, and limited frameworks exist to guide treatment. METHODS: Using RAND/University of California, Los Angeles (UCLA) Appropriateness Methods, a modified Delphi approach identified consensus statements to guide LPR treatment. Experts independently and blindly scored proposed statements on importance, scientific acceptability, usability, and feasibility in a four-round iterative process. Accepted measures reached scores with ≥ 80% agreement in the 7-9 range (on a 9-point Likert scale) across all four categories. RESULTS: Fifteen experts rated 36 proposed initial statements. In round one, 10 (27.8%) statements were rated as valid. In round two, 8 statements were modified based on panel suggestions, and experts subsequently rated 5 of these statements as valid. Round three's discussion refined statements not yet accepted, and in round four, additional voting identified 2 additional statements as valid. In total, 17 (47.2%) best practice statements reached consensus, touching on topics as varied as role of empiric treatment, medication use, lifestyle modifications, and indications for laryngoscopy. CONCLUSION: Using a well-tested methodology, best practice statements in the treatment of LPR were identified. The statements serve to guide physicians on LPR treatment considerations.

Injectable and Repeatable Inductive Heating of Iron Oxide Nanoparticle-Enhanced "PHIL" Embolic toward Tumor Treatment.

Deep-seated tumors of the liver, brain, and other organ systems often recur after initial surgical, chemotherapeutic, radiation, or focal treatments. Repeating these treatments is often invasive and traumatic. We propose an iron oxide nanoparticle (IONP)-enhanced precipitating hydrophobic injectable liquid (PHIL, MicroVention inc.) embolic as a localized dual treatment implant for nutrient deprivation and multiple repeatable thermal ablation. Following a single injection, multiple thermal treatments can be repeated as needed, based on monitoring of tumor growth/recurrence. Herein we show the ability to create an injectable stable PHIL-IONP solution, monitor deposition of the PHIL-IONP precipitate dispersion by µCT, and gauge the IONP distribution within the embolic by magnetic resonance imaging. Once precipitated, the implant could be heated to reach therapeutic temperatures >8 °C for thermal ablation (clinical temperature of ∼45 °C), in a model disk and a 3D tumor bed model. Heat output was not affected by physiological conditions, multiple heating sessions, or heating at intervals over a 1 month duration. Further, in ex vivo mice hind-limb tumors, we could noninvasively heat the embolic to an "ablative" temperature elevation of 17 °C (clinically 54 °C) in the first 5 min and maintain the temperature rise over +8 °C (clinically a temperature of 45 °C) for longer than 15 min.

Informal carers' support needs, facilitators and barriers in the transitional care of older adults: A qualitative study.

INTRODUCTION: Inclusion of informal carers in transitional care is challenging because of fast throughput and service fragmentation. This study aimed to understand informal carers' needs during the care transitions of older adults from inpatient care to the community. METHODS: A qualitative exploratory design was used with mixed-methods data collection. Seventeen semi-structured telephone interviews were conducted with family carers; one focus group was conducted by videoconference with two family carers and three community-based advocacy and aged care providers; and eight semi-structured telephone interviews were undertaken with healthcare practitioners from rehabilitation services. Data were thematically analysed. FINDINGS: All carers described the main social challenge that they needed to address in transitional care as 'Needing to sustain family'. Carers reported their social needs across five solutions: 'Partnering with carers', 'Advocating for discharge', 'Accessing streamlined multidisciplinary care', 'Knowing how to care' and 'Accessing follow-up care in the community'. Focus group participants endorsed the findings from the carer interviews and added the theme 'Putting responsibility back onto carers'. All healthcare practitioners described the main social challenge that they needed to address as 'Needing to engage carers'. They reported their social solutions in three themes: 'Communicating with carers', 'Planning with carers' and 'Educating carers'. DISCUSSION: Findings highlight the importance of reconstructing the meaning of transitional care and relevant outcomes to be inclusive of carers' experiences and their focus on sustaining family. Transitional care that includes carers should commence at the time of hospital admission of the older adult. CONCLUSIONS: Future sustainable and high-quality health services for older adults will require transitional care that includes carers and older adults and efficient use of inpatient and community care resources. Healthcare professionals will require education and skills in the provision of transitional care that includes carers. To meet carers' support needs, models of transitional care inclusive of carers and older adults should be developed, implemented and evaluated. PUBLIC CONTRIBUTION: This study was conducted with the guidance of a Carer Advisory Group comprising informal carers with experience of care transitions of older adults they support and community-based organizations providing care and advocacy support to informal carers.

Photothermal heating of titanium nitride nanomaterials for fast and uniform laser warming of cryopreserved biomaterials.

Titanium nitride (TiN) is presented as an alternative plasmonic nanomaterial to the commonly used gold (Au) for its potential use in laser rewarming of cryopreserved biomaterials. The rewarming of vitrified, glass like state, cryopreserved biomaterials is a delicate process as potential ice formation leads to mechanical stress and cracking on a macroscale, and damage to cell walls and DNA on a microscale, ultimately leading to the destruction of the biomaterial. The use of plasmonic nanomaterials dispersed in cryoprotective agent solutions to rapidly convert optical radiation into heat, generally supplied by a focused laser beam, proposes a novel approach to overcome this difficulty. This study focuses on the performance of TiN nanoparticles (NPs), since they present high thermal stability and are inexpensive compared to Au. To uniformly warm up the nanomaterial solutions, a beam splitting laser system was developed to heat samples from multiple sides with equal beam energy distribution. In addition, uniform laser warming requires equal distribution of absorption and scattering properties in the nanomaterials. Preliminary results demonstrated higher absorption but less scattering in TiN NPs than Au nanorods (GNRs). This led to the development of TiN clusters, synthetized by nanoparticle agglomeration, to increase the scattering cross-section of the material. Overall, this study analyzed the heating rate, thermal efficiency, and heating uniformity of TiN NPs and clusters in comparison to GNRs at different solution concentrations. TiN NPs and clusters demonstrated higher heating rates and solution temperatures, while only clusters led to a significantly improved uniformity in heating. These results highlight a promising alternative plasmonic nanomaterial to rewarm cryopreserved biological systems in the future.

Improving transitional care communication for older Australians from hospital to home: Co-design of the TRANSITION tool.

This study aimed to develop and evaluate a communication tool to guide transitional care for older patients. Using experience-based co-design, a communication tool resulted from the triangulation of data collected from three study phases. From 2015 to 2016, semi-structured interviews and co-design focus groups were undertaken with older patients, carers and healthcare practitioners across acute, rehabilitation and community settings. The evaluation phase, conducted in 2017-2018, involved use of the communication tool by healthcare practitioners in a multidisciplinary care team with older patients in acute care and semi-structured interviews with healthcare practitioners about the acceptability and feasibility of the tool. A total of 103 patients, carers and healthcare practitioners took part. In semi-structured interviews, patients and carers reported needing to become independent in care transitions, which was supported by discussing the transitional care plan with healthcare practitioners. Interviews with healthcare practitioners identified that their need for fast and safe care transitions was supported by team discussion and by engaging patients and carers in their transitional care plan. Co-design focus group participants identified principles guiding transitional care including patient-centred communication. Data collected from semi-structured interviews and co-design focus groups were used to develop a prototype communication tool to guide conversations about discharge care between healthcare practitioners and older patients. Following use, healthcare practitioners reported that the communication tool was feasible and acceptable although some nurses perceived that transitional care was not their role. The communication tool provides an evidence-based resource for ward nurses to support transitional care continuity in multidisciplinary models.

Phosphonate coating of commercial iron oxide nanoparticles for nanowarming cryopreserved samples.

New preservation technologies may allow for organ banking similar to blood and biomaterial banking approaches. Using cryoprotective agents (CPAs), aqueous solutions with organic components such as DMSO, propylene glycol, and added salts and sugars, organs can be used to vitrify and store organs at -140 °C. When needed, these organs can be rewarmed in a rapid and uniform manner if CPAs are supplemented with iron oxide nanoparticles (IONPs) in an applied radiofrequency field. Speed and uniformity of warming are both IONP concentration and CPA suspension dependent. Here we present a coating method of small molecule phosphonate linker (PLink) and biocompatible polymer (i.e. polyethylene glycol PEG) that tunes stability and increases the maximum allowable concentration of IONPs in CPA suspension. PLink contains a phosphonate 'anchor' for high irreversible binding to iron oxide and a carboxylic acid 'handle' for ligand attachment. PLink-PEG removes and replaces the initial coating layer of commercially available IONPs (EMG1200 (hydrophobic) and EMG308 (hydrophilic) Ferrotec, Inc., increasing colloidal stability and decreasing aggregation in both water and CPAs, (verified with dynamic light scattering) from minutes (uncoated) to up to 6 days. Heating properties of EMG1200, specific absorption rate (SAR), measured using an applied field of 360 kHz and 20 kA m-1, increased from 20 to 180 W per g Fe with increasing PLink-PEG5000. PEG replacing the initially hydrophobic coating decreased aggregation in water and CPA, consistent with earlier studies on heating performance. Furthermore, although the size is minimized at 0.20 mol PEG per g Fe, heating is not maximized until concentrations above 0.43 mol PEG per g Fe on EMG1200. SAR on hydrophilic EMG308 was preserved at 400 W per g Fe regardless of the amount of PLink added to the core. Herein concentrations of IONP in VS55 (common CPA) significantly above our previous capabilities, sIONP at 10 mg Fe per mL, was reached, 25 mg Fe per mL of 308-PEG5000 and 60 mg Fe per mL of 1200-PEG5000, approaching stock EMG308 in water, 60 mg Fe per mL. Furthermore, at these concentrations cryopreserved Human dermal fibroblast cells were successfully nanowarmed (at applied fields described above), with higher viability as compared to convective rewarming in a water bath and heating rate close to 200 °C min-1, 2.5 times faster than our current system. Using PLink as the coating method allowed for higher concentrations of IONPs to be successfully suspended in CPA without affecting the heating ability. Additionally, the model ligand, PEG, allowed for increased stability over time in nanowarming experiments.