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Point-of-Care Ultrasound Curricula in Physician Assistant Programs: Recommendations From a Panel of Experts.
(The journal of physician assistant education : the official journal of the Physician Assistant Education Association, 2025-03) Breunig, Michael; Bafuma, Patrick; Bludorn, Janelle
Introduction
Point-of-care ultrasound (POCUS) integration into physician assistant (PA) program curricula continues to increase; however, guidance on specific curricular components is lacking. This study aims to establish expert consensus on essential POCUS curriculum components for PA programs.Methods
A validated survey was administered to an expert panel of 100 PAs. Respondents rated the appropriateness of various curriculum components on a 9-point Likert scale. Data analysis included descriptive statistics and measures of consensus. Recommendations were categorized as strongly recommended, recommended, conditional recommended, and not recommended based on appropriateness and consensus levels.Results
The survey had a 63% response rate (n = 63). Strongly recommended and recommended determinations were made for PA curricula to include foundational POCUS concepts, obtaining specific views for most body system areas, identification of specific anatomical structures and findings, and procedural guidance.Discussion
Integrating POCUS into PA education is essential for enhancing diagnostic and clinical skills. Foundational concepts received strong support, while advanced applications had varied consensus, suggesting tailored curricula based on program-specific goals. These recommendations provide a structured framework for comprehensive POCUS training, aligning with broader trends in medical education and equipping PAs with essential ultrasound skills for diverse clinical settings.The effects of mitochondrial damaging reagents on membrane potential and mitophagy induction, with implications in neurodegeneration
(2023-05-03) McBane, Jason
Mitochondria are double membrane-bound organelles with established roles in metabolism, biosynthesis, and energy production. Various mitochondrial quality control mechanisms have evolved to maintain the mitochondrial network. One such mechanism is mitophagy, where damaged mitochondria are removed from the cell via autophagosome engulfment and lysosome degradation. Mutations and deficiencies in mitophagy components are linked to Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS), suggesting mitochondrial regulation is vital for cellular homeostasis. As a result, research efforts have focused on understanding mitophagy by inducing the pathway using various mitochondrial damaging reagents. However, these studies have resulted in discrepancies in the literature, highlighting our gap in knowledge of the type and severity of mitochondrial damage that induces mitophagy and drives neurodegeneration. Here, I used quantitative live-cell imaging of HeLa cells to determine whether four mitochondrial damaging reagents are comparable in depolarizing the mitochondrial membrane potential and inducing mitophagy. These reagents include carbonyl cyanide m-chlorophenyl hydrazone (CCCP), valinomycin, rotenone, and deferiprone (DFP). I found that valinomycin is the most potent at uncoupling the membrane potential, and that only reagents that depolarize the membrane induce mitophagy. My results shed light on comparable and effective in vitro mitophagy-inducing damaging paradigms that could be used to further our understanding of the etiology of neurodegenerative diseases and potential therapies.
Acoustofluidic-based therapeutic apheresis system.
(Nature communications, 2024-08) Wu, Mengxi; Ma, Zhiteng; Xu, Xianchen; Lu, Brandon; Gu, Yuyang; Yoon, Janghoon; Xia, Jianping; Ma, Zhehan; Upreti, Neil; Anwar, Imran J; Knechtle, Stuart J; T Chambers, Eileen; Kwun, Jean; Lee, Luke P; Huang, Tony Jun
Therapeutic apheresis aims to selectively remove pathogenic substances, such as antibodies that trigger various symptoms and diseases. Unfortunately, current apheresis devices cannot handle small blood volumes in infants or small animals, hindering the testing of animal model advancements. This limitation restricts our ability to provide treatment options for particularly susceptible infants and children with limited therapeutic alternatives. Here, we report our solution to these challenges through an acoustofluidic-based therapeutic apheresis system designed for processing small blood volumes. Our design integrates an acoustofluidic device with a fluidic stabilizer array on a chip, separating blood components from minimal extracorporeal volumes. We carried out plasma apheresis in mouse models, each with a blood volume of just 280 μL. Additionally, we achieved successful plasmapheresis in a sensitized mouse, significantly lowering preformed donor-specific antibodies and enabling desensitization in a transplantation model. Our system offers a new solution for small-sized subjects, filling a critical gap in existing technologies and providing potential benefits for a wide range of patients.
An acoustofluidic device for the automated separation of platelet-reduced plasma from whole blood.
(Microsystems & nanoengineering, 2024-01) Ma, Zhehan; Xia, Jianping; Upreti, Neil; David, Emeraghi; Rufo, Joseph; Gu, Yuyang; Yang, Kaichun; Yang, Shujie; Xu, Xiangchen; Kwun, Jean; Chambers, Eileen; Huang, Tony Jun
Separating plasma from whole blood is an important sample processing technique required for fundamental biomedical research, medical diagnostics, and therapeutic applications. Traditional protocols for plasma isolation require multiple centrifugation steps or multiunit microfluidic processing to sequentially remove large red blood cells (RBCs) and white blood cells (WBCs), followed by the removal of small platelets. Here, we present an acoustofluidic platform capable of efficiently removing RBCs, WBCs, and platelets from whole blood in a single step. By leveraging differences in the acoustic impedances of fluids, our device generates significantly greater forces on suspended particles than conventional microfluidic approaches, enabling the removal of both large blood cells and smaller platelets in a single unit. As a result, undiluted human whole blood can be processed by our device to remove both blood cells and platelets (>90%) at low voltages (25 Vpp). The ability to successfully remove blood cells and platelets from plasma without altering the properties of the proteins and antibodies present creates numerous potential applications for our platform in biomedical research, as well as plasma-based diagnostics and therapeutics. Furthermore, the microfluidic nature of our device offers advantages such as portability, cost efficiency, and the ability to process small-volume samples.
Modeling BK Virus Infection in Renal Transplant Recipients.
(Viruses, 2024-12) Myers, Nicholas; Droz, Dana; Rogers, Bruce W; Tran, Hien; Flores, Kevin B; Chan, Cliburn; Knechtle, Stuart J; Jackson, Annette M; Luo, Xunrong; Chambers, Eileen T; McCarthy, Janice M
Kidney transplant recipients require a lifelong protocol of immunosuppressive therapy to prevent graft rejection. However, these same medications leave them susceptible to opportunistic infections. One pathogen of particular concern is human polyomavirus 1, also known as BK virus (BKPyV). This virus attacks kidney tubule epithelial cells and is a direct threat to the health of the graft. Current standard of care in BK virus-infected transplant recipients is reduction in immunosuppressant therapy, to allow the patient's immune system to control the virus. This requires a delicate balance; immune suppression must be strong enough to prevent rejection, yet weak enough to allow viral clearance. We seek to model viral and immune dynamics with the ultimate goal of applying optimal control methods to this problem. In this paper, we begin with a previously published model and make simplifying assumptions that reduce the number of parameters from 20 to 14. We calibrate our model using newly available patient data and a detailed sensitivity analysis. Numerical results for multiple patients are given to show that the newer model reflects observed dynamics well.