Development of a Telemetry Unit for Wireless Monitoring of Bone Strain

Computational Infrastructure and Informatics Poster SessionA telemetry unit designed to monitor strain in bones is presented. This unit allows studying the relationship between bone load and bone mass in scenarios that were not possible with current setup. The current measuring setup employs a bench top load instrument and a data acquisition unit to read the output of strain gage sensors attached to the ulna of a mouse. Although precise, this setup is bulky and requires complete immobilization of the mouse. The telemetry unit developed by the authors replaces the data acquisition unit in the current setup and is able to wirelessly transmit the readings of the strain gage to a remote computer. The telemetry unit makes possible the collection of bone strain data in scenarios where the mouse is free to move or while performing fatigue-inducing exercises. The unit has been designed around an ultra low-power microcontroller (MSP430). The microcontroller makes the design highly flexible and programmable. The telemetry unit also includes a high-performance instrumentation amplifier to amplify the strain gage output. The gain and offset of the amplifier are digitally set by the microcontroller eliminating the use of manual potentiometers. The board has an expansion connector that allows up to 16 additional strain gages to be connected to the unit and incorporates a low-power radio transceiver operating in the 2.4 GHz ISM band. The data transmitted by the unit is received by a base station connected to a computer via a USB cable. The telemetry unit has been tested in a lab setting and is able to transmit the strain data at distances greater than 20 m while consuming less than 30 mW of power. This low power consumption allows the unit to be powered by a micro-battery weighting less than 3 grams. The telemetry unit can be used in other biomedical applications such as in the monitoring of orthopedic implants and can be easily configured to use other type of sensors

Flexible Carbon Nanotube-Based Strain Gage Sensors

Jump Starting Technologies, Patent Issues, & Translational Medicine Poster SessionAging brings about dramatic changes in the skeleton and other organ systems. Major skeletal diseases associated with aging include osteoporosis and attendant fractures (hip, spine and wrist or Collies) and osteoarthritis and its resulting need for various joint replacements. The prosthetic joint market in the United Sates is between $4-5 billion annually and estimates have suggested that this number will increase by upwards of 10$780. Equipment and lab facilities are available at UMKC. Carbon nanotubes are commercially available from NanoLab Inc. Copper nanoparticles and other chemicals can be acquired from Sigma-Aldrich. A timeline of one year will be needed to fine tune the fabrication process and characterize the strain gages

An embedded multichannel telemetry unit for bone strain monitoring

Abstract An embedded telemetry unit for bone strain monitoring is presented. The telemetry unit is designed using commercially available components to lower design time and manufacturing costs. The unit can read up to eight strain gauges and measures 2.4 cm × 1.3 cm × 0.7 cm. The unit is powered from a small Li-polymer battery that can be recharged wirelessly through tissue, making it suitable for implanted applications. The average current consumption of the telemetry unit is 1.9 mA while transmitting at a rate of 75 kps and at a sampling rate of 20 Hz. The telemetry unit also features a power-down mode to minimize its power consumption when it is not in use. The telemetry unit operates in the 915-MHz ISM radio band. The unit was tested in an ex vivo setting with an ulna bone from a mouse and in a simulated in vivo setting with a phantom tissue. Bone strain data collected ex vivo shows that the telemetry unit can measure strain with an accuracy comparable to a more expensive benchtop data acquisition system.Peer Reviewe

Biomedical Tissue Engineering - Where We Go in the Future

Researchers and entrepreneurs examine breakthroughs in tissue engineering and regeneration that enhance healing, remodeling, and recovery

Exome-wide association study to identify rare variants influencing COVID-19 outcomes : Results from the Host Genetics Initiative

Publisher Copyright: Copyright: © 2022 Butler-Laporte et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Host genetics is a key determinant of COVID-19 outcomes. Previously, the COVID-19 Host Genetics Initiative genome-wide association study used common variants to identify multiple loci associated with COVID-19 outcomes. However, variants with the largest impact on COVID-19 outcomes are expected to be rare in the population. Hence, studying rare variants may provide additional insights into disease susceptibility and pathogenesis, thereby informing therapeutics development. Here, we combined whole-exome and whole-genome sequencing from 21 cohorts across 12 countries and performed rare variant exome-wide burden analyses for COVID-19 outcomes. In an analysis of 5,085 severe disease cases and 571,737 controls, we observed that carrying a rare deleterious variant in the SARS-CoV-2 sensor toll-like receptor TLR7 (on chromosome X) was associated with a 5.3-fold increase in severe disease (95% CI: 2.75–10.05, p = 5.41x10-7). This association was consistent across sexes. These results further support TLR7 as a genetic determinant of severe disease and suggest that larger studies on rare variants influencing COVID-19 outcomes could provide additional insights.Peer reviewe

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

First M87 Event Horizon Telescope Results. IX. Detection of Near-horizon Circular Polarization

Event Horizon Telescope (EHT) observations have revealed a bright ring of emission around the supermassive black hole at the center of the M87 galaxy. EHT images in linear polarization have further identified a coherent spiral pattern around the black hole, produced from ordered magnetic fields threading the emitting plasma. Here we present the first analysis of circular polarization using EHT data, acquired in 2017, which can potentially provide additional insights into the magnetic fields and plasma composition near the black hole. Interferometric closure quantities provide convincing evidence for the presence of circularly polarized emission on event-horizon scales. We produce images of the circular polarization using both traditional and newly developed methods. All methods find a moderate level of resolved circular polarization across the image (〈∣v∣〉 < 3.7%), consistent with the low image-integrated circular polarization fraction measured by the Atacama Large Millimeter/submillimeter Array (∣v int∣ < 1%). Despite this broad agreement, the methods show substantial variation in the morphology of the circularly polarized emission, indicating that our conclusions are strongly dependent on the imaging assumptions because of the limited baseline coverage, uncertain telescope gain calibration, and weakly polarized signal. We include this upper limit in an updated comparison to general relativistic magnetohydrodynamic simulation models. This analysis reinforces the previously reported preference for magnetically arrested accretion flow models. We find that most simulations naturally produce a low level of circular polarization consistent with our upper limit and that Faraday conversion is likely the dominant production mechanism for circular polarization at 230 GHz in M87*