CryoET of ß-amyloid and tau within postmortem Alzheimer's disease brain.

A defining pathological feature of most neurodegenerative diseases is the assembly of proteins into amyloid that form disease-specific structures1. In Alzheimer's disease, this is characterized by the deposition of ß-amyloid and tau with disease-specific conformations. The in situ structure of amyloid in the human brain is unknown. Here, using cryo-fluorescence microscopy-targeted cryo-sectioning, cryo-focused ion beam-scanning electron microscopy lift-out and cryo-electron tomography, we determined in-tissue architectures of ß-amyloid and tau pathology in a postmortem Alzheimer's disease donor brain. ß-amyloid plaques contained a mixture of fibrils, some of which were branched, and protofilaments, arranged in parallel arrays and lattice-like structures. Extracellular vesicles and cuboidal particles defined the non-amyloid constituents of ß-amyloid plaques. By contrast, tau inclusions formed parallel clusters of unbranched filaments. Subtomogram averaging a cluster of 136 tau filaments in a single tomogram revealed the polypeptide backbone conformation and filament polarity orientation of paired helical filaments within tissue. Filaments within most clusters were similar to each other, but were different between clusters, showing amyloid heterogeneity that is spatially organized by subcellular location. The in situ structural approaches outlined here for human donor tissues have applications to a broad range of neurodegenerative diseases.

Drinkable in situ-forming tough hydrogels for gastrointestinal therapeutics.

Pills are a cornerstone of medicine but can be challenging to swallow. While liquid formulations are easier to ingest, they lack the capacity to localize therapeutics with excipients nor act as controlled release devices. Here we describe drug formulations based on liquid in situ-forming tough (LIFT) hydrogels that bridge the advantages of solid and liquid dosage forms. LIFT hydrogels form directly in the stomach through sequential ingestion of a crosslinker solution of calcium and dithiol crosslinkers, followed by a drug-containing polymer solution of alginate and four-arm poly(ethylene glycol)-maleimide. We show that LIFT hydrogels robustly form in the stomachs of live rats and pigs, and are mechanically tough, biocompatible and safely cleared after 24 h. LIFT hydrogels deliver a total drug dose comparable to unencapsulated drug in a controlled manner, and protect encapsulated therapeutic enzymes and bacteria from gastric acid-mediated deactivation. Overall, LIFT hydrogels may expand access to advanced therapeutics for patients with difficulty swallowing.

Synthetic extremophiles via species-specific formulations improve microbial therapeutics.

Microorganisms typically used to produce food and pharmaceuticals are now being explored as medicines and agricultural supplements. However, maintaining high viability from manufacturing until use remains an important challenge, requiring sophisticated cold chains and packaging. Here we report synthetic extremophiles of industrially relevant gram-negative bacteria (Escherichia coli Nissle 1917, Ensifer meliloti), gram-positive bacteria (Lactobacillus plantarum) and yeast (Saccharomyces boulardii). We develop a high-throughput pipeline to define species-specific materials that enable survival through drying, elevated temperatures, organic solvents and ionizing radiation. Using this pipeline, we enhance the stability of E. coli Nissle 1917 by more than four orders of magnitude over commercial formulations and demonstrate its capacity to remain viable while undergoing tableting and pharmaceutical processing. We further show, in live animals and plants, that synthetic extremophiles remain functional against enteric pathogens and as nitrogen-fixing plant supplements even after exposure to elevated temperatures. This synthetic, material-based stabilization enhances our capacity to apply microorganisms in extreme environments on Earth and potentially during exploratory space travel.

Primary total talus arthroplasty for Hawkins type IV talar neck fracture dislocation.

A woman in her 40s was involved in a motor vehicle collision and sustained a closed Hawkins type IV talar neck fracture dislocation. The injury was treated with reduction, percutaneous pinning and spanning external fixation, followed by definitive treatment with total talus arthroplasty (TTA) 2 months following injury. This is a unique example of definitive management for a severe talar neck fracture dislocation with arthroplasty in the subacute setting. TTA is perhaps a primary option for these injuries at high risk for avascular necrosis, non-union, malunion and post-traumatic arthritis.

Wave-Based Outcomes Comparison of Hospitalized COVID-19 Patients: A Retrospective Multicenter Cohort Study From Rural Appalachia.

BACKGROUND: There has been little to no characterization of the pandemic's effects on rural Central Appalachia, in which health disparities in the pre-COVID-19 era have historically plagued. This is the first study to compare wave-based differences in outcomes of hospitalized patients with COVID-19 in the rural Appalachian region. This study aims to provide a more comprehensive understanding of the effects of the COVID-19 pandemic on large rural communities and Appalachia. METHODS: This is a retrospective cohort study of hospitalized patients with COVID-19 between April 2020 and June 2022, which includes 13 Appalachian Regional Healthcare (ARH) hospitals. The primary outcome of the study was in-hospital mortality. Secondary outcomes included intensive care unit (ICU) stay, need for mechanical ventilation, length of hospital stay, 1-30-day re-admittance, 30-60-day re-admittance, and thromboembolism incidence risk. RESULTS: The second wave of infections during the pandemic demonstrated the highest mortality with higher odds of affecting younger patients. The third wave demonstrated similar mortality to the first wave. Elderly patients and patients with chronic morbidities demonstrated the highest mortality and morbidity and the highest requirement for mechanical ventilation across the three waves. Vaccination lowered the odds of mechanical ventilation and ICU stay. CONCLUSIONS: This study comprehensively characterizes the impact of the COVID-19 pandemic in rural regions of Appalachian Kentucky and West Virginia. Future studies comparing differences between rural and urban geographies may be able to distinguish whether the disparities in these regions played a role in the impact on residents.

An ingestible self-propelling device for intestinal reanimation.

Postoperative ileus (POI) is the leading cause of prolonged hospital stay after abdominal surgery and is characterized by a functional paralysis of the digestive tract, leading to symptoms such as constipation, vomiting, and functional obstruction. Current treatments are mainly supportive and inefficacious and yield acute side effects. Although electrical stimulation studies have demonstrated encouraging pacing and entraining of the intestinal slow waves, no devices exist today to enable targeted intestinal reanimation. Here, we developed an ingestible self-propelling device for intestinal reanimation (INSPIRE) capable of restoring peristalsis through luminal electrical stimulation. Optimizing mechanical, material, and electrical design parameters, we validated optimal deployment, intestinal electrical luminal contact, self-propelling capability, safety, and degradation of the device in ex vivo and in vivo swine models. We compared the INSPIRE's effect on motility in models of normal and depressed motility and chemically induced ileus. Intestinal contraction improved by 44% in anesthetized animals and up to 140% in chemically induced ileus cases. In addition, passage time decreased from, on average, 8.6 days in controls to 2.5 days with the INSPIRE device, demonstrating significant improvement in motility. Luminal electrical stimulation of the intestine via the INSPIRE efficaciously restored peristaltic activity. This noninvasive option offers a promising solution for the treatment of ileus and other motility disorders.

An ingestible, battery-free, tissue-adhering robotic interface for non-invasive and chronic electrostimulation of the gut.

Ingestible electronics have the capacity to transform our ability to effectively diagnose and potentially treat a broad set of conditions. Current applications could be significantly enhanced by addressing poor electrode-tissue contact, lack of navigation, short dwell time, and limited battery life. Here we report the development of an ingestible, battery-free, and tissue-adhering robotic interface (IngRI) for non-invasive and chronic electrostimulation of the gut, which addresses challenges associated with contact, navigation, retention, and powering (C-N-R-P) faced by existing ingestibles. We show that near-field inductive coupling operating near 13.56 MHz was sufficient to power and modulate the IngRI to deliver therapeutically relevant electrostimulation, which can be further enhanced by a bio-inspired, hydrogel-enabled adhesive interface. In swine models, we demonstrated the electrical interaction of IngRI with the gastric mucosa by recording conductive signaling from the subcutaneous space. We further observed changes in plasma ghrelin levels, the "hunger hormone," while IngRI was activated in vivo, demonstrating its clinical potential in regulating appetite and treating other endocrine conditions. The results of this study suggest that concepts inspired by soft and wireless skin-interfacing electronic devices can be applied to ingestible electronics with potential clinical applications for evaluating and treating gastrointestinal conditions.

A vibrating ingestible bioelectronic stimulator modulates gastric stretch receptors for illusory satiety.

Effective therapies for obesity require invasive surgical and endoscopic interventions or high patient adherence, making it challenging for patients with obesity to effectively manage their disease. Gastric mechanoreceptors sense distension of the stomach and perform volume-dependent vagal signaling to initiate the gastric phase and influence satiety. In this study, we developed a new luminal stimulation modality to specifically activate these gastric stretch receptors to elicit a vagal afferent response commensurate with mechanical distension. We designed the Vibrating Ingestible BioElectronic Stimulator (VIBES) pill, an ingestible device that performs luminal vibratory stimulation to activate mechanoreceptors and stroke mucosal receptors, which induces serotonin release and yields a hormonal metabolic response commensurate with a fed state. We evaluated VIBES across 108 meals in swine which consistently led to diminished food intake (~40%, P < 0.0001) and minimized the weight gain rate (P < 0.05) as compared to untreated controls. Application of mechanoreceptor biology could transform our capacity to help patients suffering from nutritional disorders.