Regional access to a centralized extracorporeal membrane oxygenation (ECMO) service in Victoria, Australia.

Introduction: Victoria, Australia provides a centralised state ECMO service, supported by ambulance retrieval. Equity of access to this service has not been previously described. Objective: Describe the characteristics of ECMO recipients and quantify geographical and socioeconomic influence on access. Design: Retrospective observational study with spatial mapping. Participants and setting: Adult (≥18 years) ECMO recipients from July 2016-June 2022. Data from administrative Victorian Admissions Episodes Database analysed in conjunction with Australian Urban Research Infrastructure Network population data and choropleth mapping. Presumed ECMO modes were inferred from cardiopulmonary bypass and pre-hospital cardiac arrest codes. Spatial autoregressive models including Moran's test used for spatial lag testing. Outcomes: Demographics and outcomes of ECMO recipients; ECMO incidence by patient residence (Statistical-Area Level 2, SA-2) and Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD); and ECMO utilisation adjusted for patient factors and linear distance from the central ECMO referral site. Results: 631 adults received ECMO over 6 years, after exclusion of paediatric (n = 242), duplicate (n = 135), and interstate or incomplete (n = 72) records. Mean age was 51.8 years, and 68.8 % were male. Overall ECMO incidence was 3.00 ± 3.95 per 105 population. 135 (21.4 %) were presumed VA-ECMO, 59 (9.3 %) presumed ECPR, and 437 (69.3 %) presumed VV-ECMO. Spatial lag was non-significant after adjusting for patient characteristics. Distance from the central referral site (dy/dx = 0.19, 95% CI -0.41-0.04, p = 0.105) and IRSAD score (dy/dx = 0.17, 95% CI -0.19-0.53, p = 0.359) did not predict ECMO utilisation. Conclusion: Victorian ECMO incidence rates were low. We did not find evidence of inequity of access to ECMO irrespective of regional area or socioeconomic status.

Tailored Nucleic Acid Architectures at Gold Surfaces for Controlled Therapeutic Release.

Nucleic acids are versatile materials capable of forming smart nanocarriers with highly controllable therapeutic delivery. DNA-gated release is a mechanism by which DNA oligonucleotides physically block the release of encapsulated drugs from porous nanoparticles. We extend this mechanism to be used with drugs bound to the surface of DNA-capped gold nanoparticles (AuNPs). We investigated DNA monolayers of different thicknesses and hybridization states to determine how DNA surface architecture can affect the release of a template drug bound to the gold surface. DNA layers are investigated on the planar gold surface via quartz crystal microbalance with dissipation and on AuNPs via dynamic light scattering. The resultant layer architectures were studied for their effect on the release rate of drugs. We observed that varying DNA architectures on AuNPs result in different release rates of the drug. The rate of drug release can be slowed using either folded or randomly coiled DNA sequences, which act as a physical barrier to diffusion. DNA monolayers with upright orientation release drugs more quickly. When the longer single-stranded DNA is used, the drug release is slowed even further. However, even upright DNA layers provide a barrier to drug diffusion at longer sequence lengths. We hypothesize that it is the architecture of the DNA layer, influenced by the folded or upright orientation of individual DNA molecules, that affects the free diffusion of the drug away from the AuNP surface. This mechanism may improve the biological availability of many surface-bound drugs on solid, DNA-capped nanoparticles.

Comparison of Dorsal-to-Ventral Ratios of the Cervical Paraspinal Musculature in French Bulldogs With and Without Cervical Intervertebral Disk Disease and Two Other Breeds Based on CT Scan Measurements.

Objective: To objectively assess the cervical paraspinal musculature of French bulldogs (FBs) using computed tomography (CT) scan-based measurements, outline differences in other breeds published in the literature, and investigate the potential influence of its cervical paraspinal musculature on predisposed sites for intervertebral disk disease. Animals: Thirty FBs that underwent CT scans of the cervical spine from the skull to C7/T1 were enrolled. Fifteen dogs were patients suffering from intervertebral disk herniation (IVDH group), and 15 dogs underwent CT scans due to brachycephalic obstructive airway syndrome (BOAS group). Methods: At the level of each cervical intervertebral disk from C2/C3 to C7/T1, measurements were performed and statistically analyzed. On the sagittal CT scan reconstruction, the height ratio of the dorsal to ventral paraspinal musculature and the angle of the disk axis to vertebral body length were assessed. On the transverse plane, the area ratio of the dorsal and ventral paraspinal musculature and the ratio of force moments were determined at each intervertebral disk level. Finally, ratios were compared to the values of Labrador retrievers and dachshunds published by Hartmann et al. (1). Results: Comparing the two FB groups, one significant difference was detected in the mean height ratio of the dorsal to ventral paraspinal musculature at the level of C5/C6 (P = 0.0092) and C6/C7 (P = 0.0076), with IVDH FBs having the more prominent dorsal paraspinal musculature. At the level of C3/C4, a significantly less prominent dorsal paraspinal musculature in FBs than in dachshunds (P = 0.0058) and a significantly steeper disk to vertebral body angulation were observed (P = 0.0005). Conclusion: Although some incidental differences were found, most parameters did not significantly differ between the BOAS and IVDH FBs. Significant conformational differences in the cervical paraspinal musculature and disk to vertebral body length angulation were found between FBs and two other breeds (chondrodystrophic and non-chondrodystrophic). This study's findings suggest that the paraspinal musculature is an additional biomechanical influencing factor on the preferential sites of IVDH in the cervical spine and that other major factors exist in IVDH development, especially in FBs.

Body weight support through a walking cane in inexperienced users with knee osteoarthritis.

BACKGROUND: Walking canes are a self-management strategy recommended for people with knee osteoarthritis (OA) by clinical practice guidelines. Ensuring that an adequate amount of body-weight support (%BWS) is taken through the walking cane is important as this reduces measures of knee joint loading. RESEARCH QUESTION: 1) How much body weight support do people with knee OA place through a cane? 2) Do measures of body weight support increase following a brief simple training session? METHODS: Seventeen individuals with knee pain who had not used a walking cane before were recruited. A standard-grip aluminum cane was then used for 1 week with limited manufacturer instructions. Following this, participants were evaluated using an instrumented force-measuring cane to assess body weight support (% total body weight) through the cane. Force data were recorded during a 430-metre walk undertaken twice; once before 10 min of cane training administered by a physiotherapist, and once immediately after training. Measures of BWS (peak force, average force, impulse equal to the average cane force times duration, and cane-ground contact duration) were extracted. Using bathroom scales, training aimed to take at least 10% body weight support through the cane. RESULTS: Before training, the average peak BWS was 7.2 ± 2.5% of total body weight. Following 10 min of training, there was a significant increase in average peak BWS by 28%, average BWS by 25%, and BWS impulse by 54% (p < 0.05). However, individual BWS responses to training were variable. Duration of cane placement increased by 22% after training (p = 0.02). Timing of peak BWS through the cane occurred at 51% of contact phase before training, and at 53% after training (p = 0.05). SIGNIFICANCE: A short training session can increase the transfer of body weight through a walking cane. However, more sophisticated feedback may be needed to achieve target levels of BWS.

Integrating fast and slow processes is essential for simulating human-freshwater interactions.

Integrated modeling is a critical tool to evaluate the behavior of coupled human-freshwater systems. However, models that do not consider both fast and slow processes may not accurately reflect the feedbacks that define complex systems. We evaluated current coupled human-freshwater system modeling approaches in the literature with a focus on categorizing feedback loops as including economic and/or socio-cultural processes and identifying the simulation of fast and slow processes in human and biophysical systems. Fast human and fast biophysical processes are well represented in the literature, but very few studies incorporate slow human and slow biophysical system processes. Challenges in simulating coupled human-freshwater systems can be overcome by quantifying various monetary and non-monetary ecosystem values and by using data aggregation techniques. Studies that incorporate both fast and slow processes have the potential to improve complex system understanding and inform more sustainable decision-making that targets effective leverage points for system change.

Factors Influencing Cane Use for the Management of Knee Osteoarthritis: A Cross-Sectional Survey.

OBJECTIVE: To investigate demographic, symptom-related, and cognitive determinants of cane use for knee osteoarthritis (OA) and prioritize the factors that could facilitate cane use in people with no previous cane use. METHODS: A survey of people ages ≥45 years with a clinical diagnosis of knee OA was conducted. The survey consisted of the following two sections: 1) demographic and cognitive determinants of cane use assessed via subscales of the Cane Cognitive Mediator Scale, and 2) 19 statements, underpinned by the Behaviour Change Wheel theoretical framework, relating to factors that could facilitate regular cane use. Logistic regression was used to examine determinants of cane use, while a priority pairwise ranking activity (1000minds software) determined the rank order of the 19 statements that could facilitate cane use. RESULTS: A total of 529 people completed Part 1 (80% females; 35% cane users) and 231 people completed Part 2. Age (odds ratio [OR] 1.06, 95% confidence interval [95% CI] 1.03- 1.09), body mass index (BMI) (OR 1.03, 95% CI 1.01-1.06), knee pain ≥3 years (OR 2.62, 95% CI 1.63-4.21) and numeric rating scale pain level while walking (OR 1.19, 95% CI 1.09-1.30) were significant independent determinants of cane use. In people who had never used a cane, statements relating to cane-use technique, fitting, knowledge of benefits, and motivation were ranked highest overall. CONCLUSION: Independent determinants of cane use include older age, higher BMI, greater pain duration, and greater severity of knee pain. Strategies targeting an individual's capability and motivation to use a cane may increase cane use among people with knee OA.