Purpose: Replicating spinal cord injury (SCI) in large animals is necessary for evaluating translational therapeutics, yet there is currently no commercial, standardized device for inducing SCI. We present the fabrication and testing of a custom impactor device for producing repeatable contusion SCI in porcine models.
Methods: The device was built, and mechanical modeling was utilized for calibration.
Rapidly administered emergency drug therapy represents life-saving treatment for a range of acute conditions including hypoglycaemia, anaphylaxis and cardiac arrest. Devices that automate emergency delivery, such as pumps and automated injectors, are limited by the low stability of liquid formulations. In contrast, dry particulate formulations of these drugs are stable but are incompatible with drug pumps and require reconstitution before administration.
View Article and Find Full Text PDFTransplanted cells can act as living drug factories capable of secreting therapeutic proteins , with applications in the treatment of Type 1 diabetes (T1D), blood borne disease, vision disorders, and degenerative neural disease, potentially representing functional cures for chronic conditions. However, attack from the host immune system represents a major challenge, requiring chronic immunosuppression to enable long-lived cell transplantation . Encapsulating cells in engineered biomaterials capable of excluding components of the host immune system while allowing for the transport of therapeutic proteins, oxygen, nutrients, metabolites, and waste products represents a potential solution.
View Article and Find Full Text PDFBackground: The kidney contains distinct glomerular and tubulointerstitial compartments with diverse cell types and extracellular matrix components. The role of immune cells in glomerular environment is crucial for dampening inflammation and maintaining homeostasis. Macrophages are innate immune cells that are influenced by their tissue microenvironment.
View Article and Find Full Text PDFSingle-molecule measurements show that many proteins, lacking any redox cofactors, nonetheless exhibit electrical conductance on the order of a nanosiemen over 10 nm distances, implying that electrons can transit an entire protein in less than a nanosecond when subject to a potential difference of less than 1 V. This is puzzling because, for fast transport (i.e.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2023
The immune isolation of cells within devices has the potential to enable long-term protein replacement and functional cures for a range of diseases, without requiring immune suppressive therapy. However, a lack of vasculature and the formation of fibrotic capsules around cell immune-isolating devices limits oxygen availability, leading to hypoxia and cell death in vivo. This is particularly problematic for pancreatic islet cells that have high O requirements.
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
September 2023
Graph neural networks (GNNs) have become effective learning techniques for many downstream network mining tasks including node and graph classification, link prediction, and network reconstruction. However, most GNN methods have been developed for homogeneous networks with only a single type of node and edge. In this work we present muxGNN, a multiplex graph neural network for heterogeneous graphs.
View Article and Find Full Text PDFNeurotransmitters and neuromodulators mediate communication between neurons and other cell types; knowledge of release dynamics is critical to understanding their physiological role in normal and pathological brain function. Investigation into transient neurotransmitter dynamics has largely been hindered due to electrical and material requirements for electrochemical stimulation and recording. Current systems require complex electronics for biasing and amplification and rely on materials that offer limited sensor selectivity and sensitivity.
View Article and Find Full Text PDFAgeing-related delays and dysregulated inflammation in wound healing are well-documented in both human and animal models. However, cellular and molecular changes underlying this impairment in healing progression are not fully understood. In this study, we characterised ageing-associated changes to macrophages in wounds of young and aged mice and investigated transcriptomic differences that may impact the progression of wound healing.
View Article and Find Full Text PDFImplantable devices capable of targeted and reversible blocking of peripheral nerve activity may provide alternatives to opioids for treating pain. Local cooling represents an attractive means for on-demand elimination of pain signals, but traditional technologies are limited by rigid, bulky form factors; imprecise cooling; and requirements for extraction surgeries. Here, we introduce soft, bioresorbable, microfluidic devices that enable delivery of focused, minimally invasive cooling power at arbitrary depths in living tissues with real-time temperature feedback control.
View Article and Find Full Text PDFObjectives: To provide a comprehensive workflow to identify top influential health misinformation about Zika on Twitter in 2016, reconstruct information dissemination networks of retweeting, contrast mis- from real information on various metrics, and investigate how Zika misinformation proliferated on social media during the Zika epidemic.
Methods: We systematically reviewed the top 5000 English-language Zika tweets, established an evidence-based definition of "misinformation," identified misinformation tweets, and matched a comparable group of real-information tweets. We developed an algorithm to reconstruct retweeting networks for 266 misinformation and 458 comparable real-information tweets.
Hematopoietic stem cells reside in the bone marrow, where they generate the effector cells that drive immune responses. However, in response to inflammation, some hematopoietic stem and progenitor cells (HSPCs) are recruited to tissue sites and undergo extramedullary hematopoiesis. Contrasting with this paradigm, here we show residence and differentiation of HSPCs in healthy gingiva, a key oral barrier in the absence of overt inflammation.
View Article and Find Full Text PDFTo provide a comprehensive workflow to identify top influential health misinformation about Zika on Twitter in 2016, reconstruct information dissemination networks of retweeting, contrast mis- from real information on various metrics, and investigate how Zika misinformation proliferated on social media during the Zika epidemic. We systematically reviewed the top 5000 English-language Zika tweets, established an evidence-based definition of "misinformation," identified misinformation tweets, and matched a comparable group of real-information tweets. We developed an algorithm to reconstruct retweeting networks for 266 misinformation and 458 comparable real-information tweets.
View Article and Find Full Text PDFCOVID-19 pathogenesis is associated with an exaggerated immune response. However, the specific cellular mediators and inflammatory components driving diverse clinical disease outcomes remain poorly understood. We undertook longitudinal immune profiling on both whole blood and peripheral blood mononuclear cells (PBMCs) of hospitalized patients during the peak of the COVID-19 pandemic in the UK.
View Article and Find Full Text PDFJMIR Public Health Surveill
July 2020
Background: Social media has become a major resource for observing and understanding public opinions using infodemiology and infoveillance methods, especially during emergencies such as disease outbreaks. For public health agencies, understanding the driving forces of web-based discussions will help deliver more effective and efficient information to general users on social media and the web.
Objective: The study aimed to identify the major contributors that drove overall Zika-related tweeting dynamics during the 2016 epidemic.
Hydrocephalus is a common disorder caused by the buildup of cerebrospinal fluid (CSF) in the brain. Treatment typically involves the surgical implantation of a pressure-regulated silicone tube assembly, known as a shunt. Unfortunately, shunts have extremely high failure rates and diagnosing shunt malfunction is challenging due to a combination of vague symptoms and a lack of a convenient means to monitor flow.
View Article and Find Full Text PDFRecently introduced classes of thin, soft, skin-mounted microfluidic systems offer powerful capabilities for continuous, real-time monitoring of total sweat loss, sweat rate and sweat biomarkers. Although these technologies operate without the cost, complexity, size, and weight associated with active components or power sources, rehydration events can render previous measurements irrelevant and detection of anomalous physiological events, such as high sweat loss, requires user engagement to observe colorimetric responses. Here we address these limitations through monolithic systems of pinch valves and suction pumps for purging of sweat as a reset mechanism to coincide with hydration events, microstructural optics for reversible readout of sweat loss, and effervescent pumps and chemesthetic agents for automated delivery of sensory warnings of excessive sweat loss.
View Article and Find Full Text PDFInfections in the post-acute phase of cerebral ischaemia impede optimal recovery by exacerbating morbidity and mortality. Our review aims to reconcile the increased infection susceptibility of patients post-stroke by consolidating our understanding of compartmentalised alterations to systemic immunity. Mounting evidence has catalogued alterations to numerous immune cell populations but an understanding of the mechanisms of long-range communication between the immune system, nervous system and other organs beyond the involvement of autonomic signalling is lacking.
View Article and Find Full Text PDFPeriodontitis is an incredibly prevalent chronic inflammatory disease, which results in the destruction of tooth supporting structures. However, in addition to causing tooth and alveolar bone loss, this oral inflammatory disease has been shown to contribute to disease states and inflammatory pathology at sites distant from the oral cavity. Epidemiological and experimental studies have linked periodontitis to the development and/or exacerbation of a plethora of other chronic diseases ranging from rheumatoid arthritis to Alzheimer's disease.
View Article and Find Full Text PDFStudies of the peripheral nervous system rely on controlled manipulation of neuronal function with pharmacologic and/or optogenetic techniques. Traditional hardware for these purposes can cause notable damage to fragile nerve tissues, create irritation at the biotic/abiotic interface, and alter the natural behaviors of animals. Here, we present a wireless, battery-free device that integrates a microscale inorganic light-emitting diode and an ultralow-power microfluidic system with an electrochemical pumping mechanism in a soft platform that can be mounted onto target peripheral nerves for programmed delivery of light and/or pharmacological agents in freely moving animals.
View Article and Find Full Text PDFNoninvasive methods for precise characterization of the thermal properties of soft biological tissues such as the skin can yield vital details about physiological health status including at critical intervals during recovery following skin injury. Here, we introduce quantitative measurement and characterization methods that allow rapid, accurate determination of the thermal conductivity of soft materials using thin, skin-like resistive sensor platforms. Systematic evaluations of skin at eight different locations and of six different synthetic skin-mimicking materials across sensor sizes, measurement times, and surface geometries (planar, highly curvilinear) validate simple scaling laws for data interpretation and parameter extraction.
View Article and Find Full Text PDFWearable sweat sensors rely either on electronics for electrochemical detection or on colorimetry for visual readout. Non-ideal form factors represent disadvantages of the former, while semiquantitative operation and narrow scope of measurable biomarkers characterize the latter. Here, we introduce a battery-free, wireless electronic sensing platform inspired by biofuel cells that integrates chronometric microfluidic platforms with embedded colorimetric assays.
View Article and Find Full Text PDFNoninvasive, in situ biochemical monitoring of physiological status, via the use of sweat, could enable new forms of health care diagnostics and personalized hydration strategies. Recent advances in sweat collection and sensing technologies offer powerful capabilities, but they are not effective for use in extreme situations such as aquatic or arid environments, because of unique challenges in eliminating interference/contamination from surrounding water, maintaining robust adhesion in the presence of viscous drag forces and/or vigorous motion, and preventing evaporation of collected sweat. This paper introduces materials and designs for waterproof, epidermal, microfluidic and electronic systems that adhere to the skin to enable capture, storage, and analysis of sweat, even while fully underwater.
View Article and Find Full Text PDFBio-integrated wearable systems can measure a broad range of biophysical, biochemical, and environmental signals to provide critical insights into overall health status and to quantify human performance. Recent advances in material science, chemical analysis techniques, device designs, and assembly methods form the foundations for a uniquely differentiated type of wearable technology, characterized by noninvasive, intimate integration with the soft, curved, time-dynamic surfaces of the body. This review summarizes the latest advances in this emerging field of "bio-integrated" technologies in a comprehensive manner that connects fundamental developments in chemistry, material science, and engineering with sensing technologies that have the potential for widespread deployment and societal benefit in human health care.
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