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Translational Animal Science Jul 2019The objective of this study was to contrast the soft tissue thickness, cranial thickness, total tissue thickness, cross-sectional brain area, and bolt-brain contact from...
The objective of this study was to contrast the soft tissue thickness, cranial thickness, total tissue thickness, cross-sectional brain area, and bolt-brain contact from the common frontal application of captive bolt euthanasia with the alternative location behind the ear in cadaver swine heads. Twenty-three cadaver heads from pigs that were approximately 136 kg and 6 mo of age were collected from a regional slaughter establishment following CO stunning and assigned to either the FRONTAL ( = 11) or the CAUDAL TO PINNA ( = 12) application of the captive bolt. The soft tissue thickness was different ( < 0.0001) between the 2 applications (FRONTAL: 8.3 ± 3.4 mm; CAUDAL TO PINNA: 56.5 ± 3.4 mm). The cranial thickness was different ( < 0.0001) between the applications (FRONTAL: 23.4 ± 2.9 mm; CAUDAL TO PINNA: 26.5 ± 2.9 mm). There was also a difference ( < 0.0001) in the total tissue thickness between the 2 applications (FRONTAL: 31.7 ± 3.8 mm; CAUDAL TO PINNA: 73.4 ± 3.8 mm). Cross-sectional area was calculated from images collected immediately after the heads were cut along the plane of bolt travel by bandsaw and was different ( = 0.0028) between the 2 applications (FRONTAL: 25.2 ± 1.3 cm; CAUDAL TO PINNA: 18.9 ± 1.3 cm). Bolt-brain contact was also assessed from the images, and a difference ( = 0.0360) between the 2 applications (FRONTAL: 100 ± 10.5%; CAUDAL TO PINNA: 66.7 ± 10.5%) was identified. The results of this study suggest that the FRONTAL application may provide a bolt path with less tissue to travel through when compared with the CAUDAL TO PINNA application for pigs of the approximate age and weight of those in this study. Ultimately, the FRONTAL location may present less risk for the captive bolt euthanasia of swine at market weight at this time. Additional refinement of the CAUDAL TO PINNA procedure and modification to the captive bolt device to penetrate to a suitable depth to ensure brain damage is recommended.
PubMed: 32704904
DOI: 10.1093/tas/txz097 -
JAMA Network Open May 2022Little is known about the long-term outcomes of mild valvular lesions.
IMPORTANCE
Little is known about the long-term outcomes of mild valvular lesions.
OBJECTIVE
To examine the associations of 3 major types of valvular lesions (aortic stenosis, trace or mild aortic regurgitation, and trace or mild mitral regurgitation) with risk of cardiovascular mortality, coronary heart disease (CHD), stroke, heart failure, and atrial fibrillation.
DESIGN, SETTING, AND PARTICIPANTS
This cohort study analyzed data from the ongoing Atherosclerosis Risk in Communities study and focused on Black participants in the Jackson, Mississippi, site who underwent echocardiography at visit 3 from 1993 to 1995. Data analysis was conducted between April 2021 and February 2022.
EXPOSURES
Three valvular lesions were analyzed: aortic sclerosis, aortic regurgitation (trace or mild), and mitral regurgitation (trace or mild).
MAIN OUTCOMES AND MEASURES
The outcomes were cardiovascular mortality, coronary heart disease, heart failure, stroke, and atrial fibrillation. Multivariable Cox proportional hazards regression models were used to examine the independent associations between the 3 valvular lesions and these outcomes.
RESULTS
A total of 2106 Black participants were included, with a mean (SD) age of 59.1 (5.6) years and 1354 women (64.3%). The baseline prevalence was 7.7% for aortic sclerosis, 15.1% for aortic regurgitation (6.1% with trace, and 9.0% with mild), and 43.0% for mitral regurgitation (29.4% with trace, and 13.6% with mild). During a median (interquartile interval) follow-up of 22.5 (15.6-23.5) years, 890 participants developed at least 1 cardiovascular outcome. Each valvular lesion was significantly associated with at least 1 cardiovascular outcome: aortic sclerosis was associated with cardiovascular mortality (adjusted hazard ratio [HR], 1.54; 95% CI, 1.06-2.22), mild mitral regurgitation was associated with atrial fibrillation (HR, 1.47; 95% CI, 1.09-1.99), and trace or mild aortic regurgitation was associated with all outcomes (HRs ranging from 1.45 [95% CI, 1.17-1.81] to 1.75 [95% CI, 1.29-2.37]) except stroke. The total number of valvular lesions had graded associations with all cardiovascular outcomes except stroke: the HR of cardiovascular mortality was 1.77 (95% CI, 1.18-2.65) for those with 2 to 3 lesions and was 1.44 (95% CI, 1.05-1.96) for those with 1 lesion vs no lesions.
CONCLUSIONS AND RELEVANCE
Results of this study indicate an association between valvular lesions, even at mild stage, and a long-term risk of cardiovascular events, suggesting the importance of recognizing and monitoring these valvular conditions.
Topics: Adult; Aortic Valve Insufficiency; Atrial Fibrillation; Cohort Studies; Female; Heart Failure; Humans; Middle Aged; Mitral Valve Insufficiency; Sclerosis; Stroke
PubMed: 35552723
DOI: 10.1001/jamanetworkopen.2022.11946 -
Heliyon Mar 2023Flow diverter or stent implantation to intracranial target lesion requires large inner diameter microcatheter navigation. The exchange method using stiff long wire is...
OBJECTIVES
Flow diverter or stent implantation to intracranial target lesion requires large inner diameter microcatheter navigation. The exchange method using stiff long wire is often necessary if it is difficult to navigate over the regular guidewire. However, this method has an intrinsic risk of vessel damage and may cause severe complications. We investigated the safety and efficacy of a new device, the Stabilizer device for navigation in a first-in-human clinical trial under the Certified Review Board agreement.
MATERIALS AND METHODS
The Stabilizer is a 320 cm length exchange wire with a stent for anchoring and is compatible with a 0.0165" microcatheter. The trial design is a prospective single-arm open-label registry. Inclusion criteria are elective flow diverter treatment or stent-assisted coiling, expected to be difficult to navigate a microcatheter with a regular micro guidewire, and obtained documented consent. The primary endpoint of the study was a hemorrhagic complication.
RESULTS
Five patients were enrolled in this trial. The median age is 52 years, ranges from 41 to 70, and all patients were female. Three aneurysms were located on the internal carotid artery, one on the vertebral artery, and one on the basilar artery. Basilar artery aneurysm was treated by stent-assisted coiling and others were treated by flow diverter deployment. All cases successfully navigate microcatheter for the treatment by the trial method using Stabilizer device without any adverse event.
CONCLUSIONS
The results from this first-in-human consecutive five cases show the safety of the Stabilizer device in neuro-endovascular therapy for navigation of devices to the intracranial target lesion.
PubMed: 36950603
DOI: 10.1016/j.heliyon.2023.e14360 -
PloS One 2021Fungal hyphal growth and branching are essential traits that allow fungi to spread and proliferate in many environments. This sustained growth is essential for a myriad... (Comparative Study)
Comparative Study
Fungal hyphal growth and branching are essential traits that allow fungi to spread and proliferate in many environments. This sustained growth is essential for a myriad of applications in health, agriculture, and industry. However, comparisons between different fungi are difficult in the absence of standardized metrics. Here, we used a microfluidic device featuring four different maze patterns to compare the growth velocity and branching frequency of fourteen filamentous fungi. These measurements result from the collective work of several labs in the form of a competition named the "Fungus Olympics." The competing fungi included five ascomycete species (ten strains total), two basidiomycete species, and two zygomycete species. We found that growth velocity within a straight channel varied from 1 to 4 μm/min. We also found that the time to complete mazes when fungal hyphae branched or turned at various angles did not correlate with linear growth velocity. We discovered that fungi in our study used one of two distinct strategies to traverse mazes: high-frequency branching in which all possible paths were explored, and low-frequency branching in which only one or two paths were explored. While the high-frequency branching helped fungi escape mazes with sharp turns faster, the low-frequency turning had a significant advantage in mazes with shallower turns. Future work will more systematically examine these trends.
Topics: Ascomycota; Basidiomycota; Biological Phenomena; Crowdsourcing; Fungi; Hyphae; Microfluidic Analytical Techniques; Species Specificity
PubMed: 34587206
DOI: 10.1371/journal.pone.0257823 -
Injury Apr 2024to assess the small-scale 3D printing feasibility and cost estimation of a device for controlled dynamization.
AIM
to assess the small-scale 3D printing feasibility and cost estimation of a device for controlled dynamization.
MATERIALS AND METHOD
The two-part device previously developed by our research group was printed with a carbon fiber-reinforced nylon filament (Gen3 CarbonX™ PA6+CF, 3DXTECH Additive Manufacturing) by a professional 3D printer (FUNMAT HT, Intamsys). Electricity, material, and labor costs for production in a Brazilian city in the Santa Catarina state were calculated.
RESULTS
The devices for controlled dynamization were successfully printed in accordance with the planned design and dimensions. Six out of 38 printed devices presented defects in the bolt hole and were discarded. The average printing time per device was 1.9 h. The average electricity, material, and labor costs per printed device were respectively US$0.71, US$13.55, and US$3.04. The total production cost per device reaches approximately US$20 by adding the average cost of defective devices (15 %).
CONCLUSION
3D printing of the controlled dynamization device is feasible and its cost seems affordable to most healthcare services, which could optimize the consolidation of diaphyseal fractures and reduce treatment time for patients.
PubMed: 38761709
DOI: 10.1016/j.injury.2024.111587 -
Materials (Basel, Switzerland) Oct 2020To evaluate mechanical performance properties of various types of cortical bone screw, cancellous bone screw, and locking bolt, we conducted torsional breaking and...
To evaluate mechanical performance properties of various types of cortical bone screw, cancellous bone screw, and locking bolt, we conducted torsional breaking and durability tests, screw driving torque tests into bone models, and screw pullout tests (crosshead speed: 10 mm/min) after driving torque tests. The 2° proof and rupture torques of a screw, which were estimated from torque versus rotational angle curves, increased with increasing core diameter of the screw. The durability limit of metallic screws obtained by four-point bending durability tests increased with increasing core diameter. The compressive, tensile, and shear strengths of the bone models used for the mechanical testing of orthopedic devices increased with increasing density of the bone model. The strength and modulus obtained for solid rigid polyurethane foam (SRPF) and cellular rigid polyurethane foam (CRPF) lay on the same straight line. Among the three strengths, the rate of increase in compressive strength with the increase in density was the highest. The maximum torque obtained by screw driving torque tests for up to 8.3 rotations (3000°) into the bone models tended to increase with increasing core diameter. In particular, the maximum torque increased linearly with increasing effective surface area of the screw, as newly defined in this work. The maximum pullout load increased linearly with increasing number of rotations and mechanical strength of the bone model. Screws with low driving torque and high pullout load were considered to have excellent fixation and are a target for development.
PubMed: 33137908
DOI: 10.3390/ma13214836 -
PloS One 2022Nowadays there are many types of glass fiber reinforced polymer(GFRP) composite beam and column joints, such as standard connection, bolted through connection, angle...
Nowadays there are many types of glass fiber reinforced polymer(GFRP) composite beam and column joints, such as standard connection, bolted through connection, angle steel connection, tube connection and so on, most of which connected by high-strength bolts with round holes. In this paper, monotonic loading tests on GFRPcomposite beam and column joints connected by slotted-hole bolts were conducted. To compare the performance of different joints, two groups of specimens were used in this study; one of group was the beam-column joints connected by the angle steel, and other group was connected by the tube connection. Specimens with different bolt holes, side plate reinforcement condition, and different bolt pre-tightening forces were studied. Failure modes, bending moment curves, plastic rotation, and yield stiffness of the two groups of joints were compared. Results showed thatthe ultimate bending moment bearing capacity of specimens with side plates could be increased by 30%. Under the same conditions, the bearing capacity of the tube joints was about 10% larger than that of the angle steel joints. Although the bearing capacity of joints was not increased by using slotted holes, plastic rotation capacity and yield stiffness of joints with slotted-hole bolts were 1.1 times than that of the ordinary round-hole bolts joints.
Topics: Bone Plates; Plastics; Polymers; Steel
PubMed: 35895725
DOI: 10.1371/journal.pone.0272136 -
International Journal of Surgery... Apr 2021New medical devices must have adequate research, such that outcomes are known, enabling patients to be consented with knowledge of the safety and efficacy of the device...
INTRODUCTION
New medical devices must have adequate research, such that outcomes are known, enabling patients to be consented with knowledge of the safety and efficacy of the device to be implanted. Device trials are challenging due to the learning curve and iterative assessment of best practice. This study is designed to pilot a national collaborative approach to medical device introduction by breast surgeons in the UK, using breast localisation devices as an exemplar. The aim is to develop an effective and transferable surgical device platform protocol design, with embedded shared learning.
METHODS AND ANALYSIS
The iBRA-net localisation study is a UK based prospective, multi-centre platform study, comparing the safety and efficacy of novel localisation devices with wire-guided breast lesion localisation for wide local excision, using Magseed® as the pilot intervention group. Centres performing breast lesion localisation for wide local excision or excision biopsy will be eligible to participate if using one of the included devices. Further intervention arms will be added as new devices are CE marked. Outcomes will be collected via an online database. The primary outcome measure will be identification of the index lesion. Participating surgeons will be asked to record shared learning events via online questionnaires and focus group interviews to inform future study arms.
ETHICS AND DISSEMINATION
The study will aim to collect data on 950 procedures for each intervention (Magseed® and wire localisation) from UK breast centres over an 18-month period. Shared learning will be prospectively evaluated via thematic analysis to refine breast localisation technique and to promote early identification of potential pitfalls and problems. Results will be presented at national and international conferences and published in peer reviewed journals.
REGISTRATION
This is a UK national audit registered with Manchester University NHS Foundation Trust.
HIGHLIGHTS
This protocol outlines a novel methodology for a collaborative national platform study to collate safety and efficacy data on new medical devices. Improved registration and audit of new medical devices is a major theme of the Cumberlege report of the Independent Medicines and Medical Devices Safety Review.We outline a protocol for a UK based multi-centre prospective audit to investigate the safety and efficacy of new surgical devices for breast lesion localisation. The study will run as a platform study using wire localisation as a control group and Magseed® as the first intervention arm.The protocol is designed for additional bolt-on intervention arms for other localisation devices, such as Hologic Localizer™ and Savi Scout®, when they become available to the European market. This will enable comparison of these devices to datasets already collected on wire and Magseed® localisation.The study includes a novel shared learning methodology using iterative online database reporting and surgical interviews to centrally distribute information on learning events, critical governance issues and recommended protocols for future use.
PubMed: 34013142
DOI: 10.29337/ijsp.136 -
European Cells & Materials May 2021Tungsten is incorporated in many industrial goods, military applications and medical devices due to its ability to impart flexibility, strength and conductance to...
Tungsten is incorporated in many industrial goods, military applications and medical devices due to its ability to impart flexibility, strength and conductance to materials. Emerging evidence has questioned the safety of tungsten exposure as studies have demonstrated it can promote tumour formation, induce pulmonary disease and alter immune function. Although tungsten is excreted from the body it can accumulate in certain organs such as the brain, colon, liver, kidneys, spleen and bones, where most of the bioaccumulation occurs. Whether prolonged tungsten exposure leads to accumulation in other tissues is unknown. The present study demonstrated that mice exposed to 15 ppm sodium tungstate for 4 weeks in their drinking water showed comparable accumulation in both the bony vertebrae and intervertebral discs (IVDs). Lumbar IVD height was significantly reduced in tungsten-exposed mice and accompanied by decreased proteoglycan content and increased fibrosis. In addition to catabolic enzymes, tungsten also increased the expression of the inflammatory cytokines IL-1β and tumour necrosis factor (TNF)-α as well as the neurotrophic factors nerve growth factor (NGF) and brain-derived nerve factor (BDNF) in IVD cells. Tungsten significantly increased the presence of nociceptive neurons at the endplates of IVDs as observed by the expression of calcitonin gene-related peptide (CGRP) and anti-protein gene product 9.5 (PGP9.5) in endplate vessels. The present study provided evidence that tungsten may enhance disc degeneration and fibrosis as well as increase the expression of markers for pain. Therefore, tungsten toxicity may play a role in disc degeneration disease.
Topics: Animals; Biomarkers; Cytokines; Fibrosis; Inflammation; Intervertebral Disc; Intervertebral Disc Degeneration; Male; Mice; Mice, Inbred C57BL; Pain; Tungsten; Up-Regulation
PubMed: 33999403
DOI: 10.22203/eCM.v041a33 -
Bioengineering (Basel, Switzerland) Mar 2019In this study, we developed the prototype of an optical imaging-based point-of-care (POC) device for monitoring human immunodeficiency virus (HIV)/acquired...
In this study, we developed the prototype of an optical imaging-based point-of-care (POC) device for monitoring human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) progression that can detect CD4+ T-lymphocytes in human blood. The proposed portable cell-counting system, Helios CD4 Analyzer (Helios), can acquire sample images and analyze the cells automatically using a simple fluorescence imaging module and sample cartridge with a three-dimensional (3D) helical minichannel. The helical minichannel formed on the cylindrical surface enables the sample cartridge to hold a cell suspension present in a fixed sample volume for absolute counting of the cells. With a given total channel length, the helical minichannel-based sample cartridge is smaller than the conventional sample cartridge with a planar microchannel. The implemented nut and bolt mechanism allows the scanning of a relatively large volume of the sample along the helical minichannel by just rotating the cylindrical chamber coupled with a single DC motor rather than using a two-axis motorized translation stage, which considerably simplifies the associated electromechanical parts. It has distinct advantages over the existing devices because of its small size and simple scanning mechanism. We optimized various imaging parameters to enhance the fluorescence detection efficiency of the prototype. Performance evaluations using human blood samples demonstrated good agreement for low CD4 count between the Helios and the PIMA, one of the most widely used POC CD4+ analyzers.
PubMed: 30875995
DOI: 10.3390/bioengineering6010024