Rapid custom prototyping of soft poroelastic biosensor for simultaneous epicardial recording and imaging.
Ontology highlight
ABSTRACT:
SUBMITTER: Kim B
PROVIDER: S-EPMC8211747 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:This paper describes a novel approach to fabricate paper-based electric circuits consisting of a paper matrix embedded with three-dimensional (3D) microchannels and liquid metal. Leveraging the high electric conductivity and good flowability of liquid metal, and metallophobic property of paper, it is possible to keep electric and mechanical functionality of the electric circuit even after a thousand cycles of deformation. Embedding liquid metal into paper matrix is a promising method to rapidly fabricate low-cost, disposable, and soft electric circuits for electronics. As a demonstration, we designed a programmable displacement transducer and applied it as variable resistors and pressure sensors. The unique metallophobic property, combined with softness, low cost and light weight, makes paper an attractive alternative to other materials in which liquid metal are currently embedded.
| S-EPMC4486998 | biostudies-literature
Project description:The emerging technique of rapid prototyping with three-dimensional (3-D) printers provides a simple yet revolutionary method for fabricating objects with arbitrary geometry. The use of 3-D printing for generating morphologically biomimetic tissue phantoms based on medical images represents a potentially major advance over existing phantom approaches. Toward the goal of image-defined phantoms, we converted a segmented fundus image of the human retina into a matrix format and edited it to achieve a geometry suitable for printing. Phantoms with vessel-simulating channels were then printed using a photoreactive resin providing biologically relevant turbidity, as determined by spectrophotometry. The morphology of printed vessels was validated by x-ray microcomputed tomography. Channels were filled with hemoglobin (Hb) solutions undergoing desaturation, and phantoms were imaged with a near-infrared hyperspectral reflectance imaging system. Additionally, a phantom was printed incorporating two disjoint vascular networks at different depths, each filled with Hb solutions at different saturation levels. Light propagation effects noted during these measurements—including the influence of vessel density and depth on Hb concentration and saturation estimates, and the effect of wavelength on vessel visualization depth—were evaluated. Overall, our findings indicated that 3-D-printed biomimetic phantoms hold significant potential as realistic and practical tools for elucidating light–tissue interactions and characterizing biophotonic system performance.
| S-EPMC4881289 | biostudies-literature
Project description:Microfluidic organs-on-chips aim to realize more biorelevant in vitro experiments compared to traditional two-dimensional (2D) static cell culture. Often such devices are fabricated via poly(dimethylsiloxane) (PDMS) soft lithography, which offers benefits (e.g., high feature resolution) along with drawbacks (e.g., prototyping time/costs). Here, we report benchtop fabrication of multilayer, PDMS-free, thermoplastic organs-on-chips via laser cut and assembly with double-sided adhesives that overcome some limitations of traditional PDMS lithography. Cut and assembled chips are economical to prototype ($2 per chip), can be fabricated in parallel within hours, and are Luer compatible. Biocompatibility was demonstrated with epithelial line Caco-2 cells and primary human small intestinal organoids. Comparable to control static Transwell cultures, Caco-2 and organoids cultured on chips formed confluent monolayers expressing tight junctions with low permeability. Caco-2 cells-on-chip differentiated ∼4 times faster, including increased mucus, compared to controls. To demonstrate the robustness of cut and assemble, we fabricated a dual membrane, trilayer chip integrating 2D and 3D compartments with accessible apical and basolateral flow chambers. As proof of concept, we cocultured a human, differentiated monolayer and intact 3D organoids within multilayered contacting compartments. The epithelium exhibited 3D tissue structure and organoids expanded close to the adjacent monolayer, retaining proliferative stem cells over 10 days. Taken together, cut and assemble offers the capability to rapidly and economically manufacture microfluidic devices, thereby presenting a compelling fabrication technique for developing organs-on-chips of various geometries to study multicellular tissues.
| S-EPMC8290094 | biostudies-literature
Project description:In vitro tissue models hold great promise for modeling diseases and drug responses. Here, we used emulsion microfluidics to form micro-organospheres (MOSs), which are droplet-encapsulated miniature three-dimensional (3D) tissue models that can be established rapidly from patient tissues or cells. MOSs retain key biological features and responses to chemo-, targeted, and radiation therapies compared with organoids. The small size and large surface-to-volume ratio of MOSs enable various applications including quantitative assessment of nutrient dependence, pathogen-host interaction for anti-viral drug screening, and a rapid potency assay for chimeric antigen receptor (CAR)-T therapy. An automated MOS imaging pipeline combined with machine learning overcomes plating variation, distinguishes tumorspheres from stroma, differentiates cytostatic versus cytotoxic drug effects, and captures resistant clones and heterogeneity in drug response. This pipeline is capable of robust assessments of drug response at individual-tumorsphere resolution and provides a rapid and high-throughput therapeutic profiling platform for precision medicine.
| S-EPMC9481922 | biostudies-literature
Project description:Recording and manipulating neural activity in awake behaving animal models requires long-term implantation of cranial implants that must address a variety of design considerations, which include preventing infection, minimizing tissue damage, mechanical strength of the implant, and MRI compatibility.Here we address these issues by designing legless, custom-fit cranial implants using structural MRI-based reconstruction of the skull and that are made from carbon-reinforced PEEK.We report several novel custom-fit radiolucent implant designs, which include a legless recording chamber, a legless stimulation chamber, a multi-channel microdrive and a head post. The fit to the skull was excellent in all cases, with no visible gaps between the base of the implants and the skull. The wound margin was minimal in size and showed no sign of infection or skin recession.Cranial implants used for neurophysiological investigation in awake behaving animals often employ methyl methacrylate (MMA) to serve as a bonding agent to secure the implant to the skull. Other designs rely on radially extending legs to secure the implant. Both of these methods have significant drawbacks. MMA is toxic to bone and frequently leads to infection while radially extending legs cause the skin to recede away from the implant, ultimately exposing bone and proliferating granulation tissue.These radiolucent implants constitute a set of technologies suitable for reliable long-term recording, which minimize infection and tissue damage.
| S-EPMC4323951 | biostudies-literature
Project description:The fabrication of microdevices for fluidic control often requires the use of flexible diaphragms in a way that requires cleanroom equipment and compromises performance. We use a CO 2 laser to perform the standard ablative techniques of cutting and engraving materials, but we also apply a method that we call laser placement. This allows us to fabricate precisely-positioned and precisely-sized, isolated diaphragms. This in turn enables the rapid prototyping of integrated multilayer microfluidic devices to form complex structures without the need for manual positioning or cleanroom equipment. The fabrication process is also remarkably rapid and capable of being scaled to manufacturing levels of production. We explore the use of these devices to construct a compact system of peristaltic pumps that can form water in oil droplets without the use of the non-pulsatile pumping systems typically required. Many devices can be fabricated at a time on a sheet by sheet basis with a fabrication process that, to our knowledge, is the fastest reported to date for devices of this type (requiring only 3 h). Moreover, this system is unusually compact and self-contained.
| S-EPMC6187535 | biostudies-literature
Project description:MotivationMany software libraries for using Hidden Markov Models in bioinformatics focus on inference tasks, such as likelihood calculation, parameter-fitting and alignment. However, construction of the state machines can be a laborious task, automation of which would be time-saving and less error-prone.ResultsWe present Machine Boss, a software tool implementing not just inference and parameter-fitting algorithms, but also a set of operations for manipulating and combining automata. The aim is to make prototyping of bioinformatics HMMs as quick and easy as the construction of regular expressions, with one-line 'recipes' for many common applications. We report data from several illustrative examples involving protein-to-DNA alignment, DNA data storage and nanopore sequence analysis.Availability and implementationMachine Boss is released under the BSD-3 open source license and is available from http://machineboss.org/.Supplementary informationSupplementary data are available at Bioinformatics online.
| S-EPMC8034524 | biostudies-literature
Project description:Spatiotemporal maps of dendritic signalling and their relationship with somatic output is fundamental to neuronal information processing, yet remain unexplored in awake animals. Here, we combine simultaneous sub-millisecond voltage and calcium two-photon imaging from distal spiny dendrites, with somatic electrical recording from spontaneously active cerebellar Purkinje neurons (PN) in awake mice. We detect discrete 1-2 ms suprathreshold voltage spikelets in the distal spiny dendrites during dendritic complex spikes. Spikelets and their calcium correlates are highly heterogeneous in number, timing and spatial distribution within and between complex spikes. Back-propagating simple spikes are highly attenuated. Highly variable 5-10 ms voltage hotspots are localized to fine dendritic processes and are reduced in size and frequency by lidocaine and CNQX. Hotspots correlated with somatic output but also, at high frequency, trigger purely dendritic calcium spikes. Summarizing, spatiotemporal signalling in PNs is far more complex, dynamic, and fine scaled than anticipated, even in resting animals.
| S-EPMC6107665 | biostudies-literature
Project description:Recently developed simultaneous multislice echo-planar imaging (EPI) sequences permit imaging of the whole brain at short repetition time (TR), allowing the cardiac fluctuations to be fully sampled in blood-oxygen-level dependent functional MRI (BOLD fMRI). A novel low computational analytical method was developed to dynamically map the passage of the pulsation signal through the brain and visualize the whole cerebral vasculature affected by the pulse signal. This algorithm is based on a simple combination of fast BOLD fMRI and the scanner's own built-in pulse oximeter.Multiple, temporally shifted copies of the pulse oximeter data (with 0.08 s shifting step and coverage of a 1-s span) were downsampled and used as cardiac pulsation regressors in a general linear model based analyses (FSL) of the fMRI data. The resulting concatenated z-statistics maps show the voxels that are affected as the cardiac signal travels through the brain.Many voxels were highly correlated with the pulsation regressor or its temporally shifted version. The dynamic and static cardiac pulsation maps obtained from both the task and resting state scans, resembled cerebral vasculature.The results demonstrated: (i) cardiac pulsation significantly affects most voxels in the brain; (ii) combining fast fMRI and this analytical method can reveal additional clinical information to functional studies.
| S-EPMC4198428 | biostudies-literature
Project description:Brain function originates from hierarchical spatial-temporal neural dynamics distributed across cortical and subcortical networks. However, techniques available to assess large-scale brain network activity with single-neuron resolution in behaving animals remain limited. Here, we present Mesotrode that integrates chronic wide-field mesoscale cortical imaging and compact multi-site cortical/subcortical cellular electrophysiology in head-fixed mice that undergo self-initiated running or orofacial movements. Specifically, we harnessed the flexibility of chronic multi-site tetrode recordings to monitor single-neuron activity in multiple subcortical structures while simultaneously imaging the mesoscale activity of the entire dorsal cortex. A mesoscale spike-triggered averaging procedure allowed the identification of cortical activity motifs preferentially associated with single-neuron spiking. Using this approach, we were able to characterize chronic single-neuron-related functional connectivity maps for up to 60 days post-implantation. Neurons recorded from distinct subcortical structures display diverse but segregated cortical maps, suggesting that neurons of different origins participate in distinct cortico-subcortical pathways. We extended the capability of Mesotrode by implanting the micro-electrode at the facial motor nerve and found that facial nerve spiking is functionally associated with the PTA, RSP, and M2 network, and optogenetic inhibition of the PTA area significantly reduced the facial movement of the mice. These findings demonstrate that Mesotrode can be used to sample different combinations of cortico-subcortical networks over prolonged periods, generating multimodal and multi-scale network activity from a single implant, offering new insights into the neural mechanisms underlying specific behaviors.
| S-EPMC10645427 | biostudies-literature