Functional implications of supercontracting muscle in the chameleon tongue retractors

2001 ◽  
Vol 204 (21) ◽  
pp. 3621-3627 ◽  
Author(s):  
Anthony Herrel ◽  
Jay J. Meyers ◽  
Peter Aerts ◽  
Kiisa C. Nishikawa
Keyword(s):  
Prey Capture ◽  
Three Dimensional ◽  
Force Production ◽  
Retractor Muscle ◽  
Muscle Physiology ◽  
Large Prey ◽  
Wide Range ◽  
Ambush Predators ◽  
Full Body

SUMMARYChameleons capture prey items using a ballistic tongue projection mechanism that is unique among lizards. During prey capture, the tongue can be projected up to two full body lengths and may extend up to 600 % of its resting length. Being ambush predators, chameleons eat infrequently and take relatively large prey. The extreme tongue elongation (sixfold) and the need to be able to retract fairly heavy prey at any given distance from the mouth are likely to place constraints on the tongue retractor muscles. The data examined here show that in vivo retractor force production is almost constant for a wide range of projection distances. An examination of muscle physiology and of the ultrastructure of the tongue retractor muscle shows that this is the result (i) of active hyoid retraction, (ii) of large muscle filament overlap at maximal tongue extension and (iii) of the supercontractile properties of the tongue retractor muscles. We suggest that the chameleon tongue retractor muscles may have evolved supercontractile properties to enable a substantial force to be produced over a wide range of tongue projection distances. This enables chameleons successfully to retract even large prey from a variety of distances in their complex three-dimensional habitat.

scholarly journals Biobanking of human gut organoids for translational research

2021 ◽  
Author(s):  
Francesca Perrone ◽  
Matthias Zilbauer
Keyword(s):  
Translational Research ◽  
Three Dimensional ◽  
Short Review ◽  
Human Gut ◽  
Exciting Field ◽  
Wide Range ◽  
Culture Models ◽  
Scientific Expertise ◽  
Key Aspects

AbstractThe development of human organoid culture models has led to unprecedented opportunities to generate self-organizing, three-dimensional miniature organs that closely mimic in vivo conditions. The ability to expand, culture, and bank such organoids now provide researchers with the opportunity to generate next-generation living biobanks, which will substantially contribute to translational research in a wide range of areas, including drug discovery and testing, regenerative medicine as well as the development of a personalized treatment approach. However, compared to traditional tissue repositories, the generation of a living organoid biobank requires a much higher level of coordination, additional resources, and scientific expertise. In this short review, we discuss the opportunities and challenges associated with the generation of a living organoid biobank. Focusing on human intestinal organoids, we highlight some of the key aspects that need to be considered and provide an outlook for future development in this exciting field.

scholarly journals Beyond the visible spectrum – applying 3D multispectral full-body imaging to the VirtoScan system

2021 ◽  
Author(s):  
Sören Kottner ◽  
Martin M. Schulz ◽  
Florian Berger ◽  
Michael Thali ◽  
Dominic Gascho
Keyword(s):  
Near Infrared ◽  
Three Dimensional ◽  
Visible Spectrum ◽  
Image Data ◽  
3D Models ◽  
Light Sources ◽  
Ct Scanner ◽  
Body Imaging ◽  
Wide Range ◽  
Full Body

AbstractMultispectral photography offers a wide range of applications for forensic investigations. It is commonly used to detect latent evidence and to enhance the visibility of findings. Additionally, three-dimensional (3D) full-body documentation has become much easier and more affordable in recent years. However, the benefits of performing 3D imaging beyond the visible (VIS) spectrum are not well known, and the technique has not been widely used in forensic medical investigations. A multicamera setup was used to employ multispectral photogrammetry between 365 and 960 nm in postmortem investigations. The multicamera setup included four modified digital cameras, ultraviolet (UV) and near-infrared (NIR) light sources and supplemental lens filters. Full-body documentation was performed in conjunction with the use of a medical X-ray computed tomography (CT) scanner to automate the imaging procedure. Textured 3D models based on multispectral datasets from four example cases were reconstructed successfully. The level of detail and overall quality of the 3D reconstructions varied depending on the spectral range of the image data. Generally, the NIR datasets showed enhanced visibility of vein patterns and specific injuries, whereas the UV-induced datasets highlighted foreign substances on the skin. Three-dimensional multispectral full-body imaging enables the detection of latent evidence that is invisible to the naked eye and allows visualization, documentation and analysis of evidence beyond the VIS spectrum.

Rapid formation of functional muscle in vitro using fibrin gels

2005 ◽  
Vol 98 (2) ◽  
pp. 706-713 ◽  
Author(s):  
Yen-Chih Huang ◽  
Robert G. Dennis ◽  
Lisa Larkin ◽  
Keith Baar
Keyword(s):  
Physiological Function ◽  
Three Dimensional ◽  
Force Production ◽  
Force Transducer ◽  
Force Frequency ◽  
Platinum Electrodes ◽  
Fibrin Gel ◽  
Novel Method

The transition of a muscle cell from a differentiated myotube into an adult myofiber is largely unstudied. This is primarily due to the difficulty of isolating specific developmental stimuli in vivo and the inability to maintain viable myotubes in culture for sufficient lengths of time. To address these limitations, a novel method for rapidly generating three-dimensional engineered muscles using fibrin gel casting has been developed. Myoblasts were seeded and differentiated on top of a fibrin gel. Cell-mediated contraction of the gel around artificial anchors placed 12 mm apart culminates 10 days after plating in a tubular structure of small myotubes (10-μm diameter) surrounded by a fibrin gel matrix. These tissues can be connected to a force transducer and electrically stimulated between parallel platinum electrodes to monitor physiological function. Three weeks after plating, the three-dimensional engineered muscle generated a maximum twitch force of 329 ± 26.3 μN and a maximal tetanic force of 805.8 ± 55 μN. The engineered muscles demonstrated normal physiological function including length-tension and force-frequency relationships. Treatment with IGF-I resulted in a 50% increase in force production, demonstrating that these muscles responded to hormonal interventions. Although the force production was maximal at 3 wk, constructs can be maintained in culture for up to 6 wk with no intervention. We conclude that fibrin-based gels provide a novel method to engineer three-dimensional functional muscle tissue and that these tissues may be used to model the development of skeletal muscle in vitro.

Effects of fatigue on the length-tetanic force relationship of the rat diaphragm

1993 ◽  
Vol 74 (1) ◽  
pp. 326-332 ◽  
Author(s):  
A. P. Gauthier ◽  
R. E. Faltus ◽  
P. T. Macklem ◽  
F. Bellemare
Keyword(s):  
High Frequency ◽  
Force Production ◽  
High Frequency Stimulation ◽  
Control Force ◽  
Optimal Length ◽  
Tetanic Force ◽  
Wide Range ◽  
Force Relationship

It has been established that the in vivo operating length of the diaphragm corresponds to a wide range of the ascending limb of its length-tetanic force relationship. To investigate the length-dependent effects of fatigue on maximum force production, we constructed length-tetanic force relationships of rat costal diaphragm strips in vitro before and after fatigue induced by repetitive supramaximal electrical field stimulations at optimal length. Two levels of fatigue were studied (i.e., force reductions of 40 and 65% at optimal length). Results indicate that fatigue, when evaluated with high-frequency stimulations, causes a proportionately larger decrease in tetanic force at short muscle lengths as seen by a smaller control force-to-fatigue force ratio and an apparent shift in the length at which active force is zero. A possible explanation for the results obtained is failure of propagation of membrane depolarization into the t-tubule system at short muscle lengths, which is aggravated by fatigue evaluated by high-frequency stimulation.

scholarly journals Disease Modeling with 3D Cell-Based Assays Using a Novel Flowchip System and High-Content Imaging

2021 ◽  
pp. 247263032110006
Author(s):  
Evan F. Cromwell ◽  
Michelle Leung ◽  
Matthew Hammer ◽  
Anthony Thai ◽  
Rashmi Rajendra ◽  
...  
Keyword(s):  
Disease Modeling ◽  
Three Dimensional ◽  
Assay System ◽  
Biological Research ◽  
Functional Evaluation ◽  
High Content Imaging ◽  
Wide Range ◽  
Sample Chamber ◽  
Cytotoxicity Effects

There is an increasing interest in using three-dimensional (3D) cell structures for modeling tumors, organs, and tissue to accelerate translational research. We describe here a novel automated organoid assay system (the Pu·MA System) combined with microfluidic-based flowchips that can facilitate 3D cell-based assays. The flowchip is composed of sample wells, which contain organoids, connected to additional multiple wells that can hold various assay reagents. Organoids are positioned in a protected chamber in sample wells, and fluids are exchanged from side reservoirs using pressure-driven flow. Media exchange, sample staining, wash steps, and other processes can be performed without disruption to or loss of 3D sample. The bottom of the sample chamber is thin, optically clear plastic compatible with high-content imaging (HCI). The whole system can be kept in an incubator, allowing long-term cellular assays to be performed. We present two examples of use of the system for biological research. In the first example, cytotoxicity effects of anticancer drugs were evaluated on HeLa and HepG2 spheroids using HCI and vascular endothelial growth factor expression. In the second application, the flowchip system was used for the functional evaluation of Ca2+ oscillations in neurospheroids. Neurospheres were incubated with neuroactive compounds, and neuronal activity was assessed using Ca2+-sensitive dyes and fast kinetic fluorescence imaging. This novel assay system using microfluidics enables automation of 3D cell-based cultures that mimic in vivo conditions, performs multidosing protocols and multiple media exchanges, provides gentle handling of spheroids and organoids, and allows a wide range of assay detection modalities.

scholarly journals Development of an arthroscopically compatible polymer additive layer manufacture technique

2017 ◽  
Vol 231 (6) ◽  
pp. 586-594
Author(s):  
Simon W Partridge ◽  
Matthew J Benning ◽  
Matthew J German ◽  
Kenneth W Dalgarno
Keyword(s):  
Three Dimensional ◽  
Proof Of Concept ◽  
Polymer Additive ◽  
Three Dimensional Printing ◽  
Functionally Gradient ◽  
Wide Range ◽  
Layer Manufacture ◽  
Dimensional Printing

This article describes a proof of concept study designed to evaluate the potential of an in vivo three-dimensional printing route to support minimally invasive repair of the musculoskeletal system. The study uses a photocurable material to additively manufacture in situ a model implant and demonstrates that this can be achieved effectively within a clinically relevant timescale. The approach has the potential to be applied with a wide range of light-curable materials and with development could be applied to create functionally gradient structures in vivo.

The effects of speed on thein vivoactivity and length of a limb muscle during the locomotion of the iguanian lizardDipsosaurus dorsalis

2001 ◽  
Vol 204 (20) ◽  
pp. 3507-3522 ◽  
Author(s):  
Frank E. Nelson ◽  
Bruce C. Jayne
Keyword(s):  
Three Dimensional ◽  
Knee Extension ◽  
Mechanical Work ◽  
Minimum Length ◽  
Shortening Velocity ◽  
Wide Range ◽  
Applied Forces ◽  
Axis Rotation ◽  
The Times

SUMMARYThe caudofemoralis muscle is the largest muscle that inserts onto the hindlimb of most ectothermic tetrapods, and previous studies hypothesize that it causes several movements that characterize the locomotion of vertebrates with a sprawling limb posture. Predicting caudofemoralis function is complicated because the muscle spans multiple joints with movements that vary with speed. Furthermore, depending on when any muscle is active relative to its change in length, its function can change from actively generating mechanical work to absorbing externally applied forces. We used synchronized electromyography, sonomicrometry and three-dimensional kinematics to determine in vivo caudofemoralis function in the desert iguana Dipsosaurus dorsalis for a wide range of speeds of locomotion from a walk to nearly maximal sprinting (50–350 cm s–1). Strain of the caudofemoralis increased with increasing tail elevation and long-axis rotation and protraction of the femur. However, knee extension only increased caudofemoralis strain when the femur was protracted. The maximum and minimum length of the caudofemoralis muscle and its average shortening velocity increased from the slowest speed up to the walk–run transition, but changed little with further increases in speed. The times of muscle shortening and lengthening were often not equal at higher locomotor speeds. Some (20–25 ms) activity occurred during lengthening of the caudofemoralis muscle before footfall. However, most caudofemoralis activity was consistent with performing positive mechanical work to flex the knee shortly after foot contact and to retract and rotate the femur throughout the propulsive phase.

Tomographic and Topographic Investigation of Poly-D,L-Lactide-Co-Glycolide Microspheres Loaded with Prostaglandine E2 for Extended Drug Release Applications

2010 ◽  
Vol 89-91 ◽  
pp. 687-691 ◽  
Author(s):  
Rolf Zehbe ◽  
Bernhard Watzer ◽  
Rainer Grupp ◽  
Sven Halstenberg ◽  
Heinrich Riesemeier ◽  
...  
Keyword(s):  
High Performance ◽  
Three Dimensional ◽  
Active Agent ◽  
Dimensional Structure ◽  
Binary Solvent ◽  
Bioactive Substances ◽  
Water Emulsion ◽  
Wide Range

Polymeric, biodegradable microspheres represent a good reliable system to investigate the release of bioactive substances in both in vitro and in vivo applications. Common biomaterials for the synthesis of these microspheres are aliphatic polyesters of the poly(α-hydroxy)acids, especially poly-L-lactides (PLA) and polyglycolides (PGA) or their copolymers poly-D,L-lactide-co-glycolides (PLGA). In our own previous studies we have developed PLGA microspheres with integrated PGE2 as model substance for a wide range of biomedical applications, especially in angiogenesis, fracture healing and cartilage repair. The synthesis is based on a binary solvent in water emulsion approach, where two different solvents are used to dissolve the active agent and the polymer, while being miscible in each other (CHCl3, ethyl acetate). Both, the degradation of the material and the release profiles were investigated using SEM and mass spectrometry coupled with gas- or high performance liquid chromatography. SEM and AFM measurements indicated a porous structure of the microspheres but could not resolve the true three dimensional structure of the microspheres. Therefore, synchrotron radiation-based µCT (SR-µCT) investigations were performed to link the release profile to the structural design of the microspheres. As a result, we were able to cross validate the experimental data from SEM and AFM with SR-µCT, demonstrating both micro-porosity and nano-porosity. The polymer itself appears to consist of 200 nm – 300 nm sized particles.

scholarly journals 3D printing of Microgel-loaded Modular LEGO-like Cages as Instructive Scaffolds for Tissue Engineering

2020 ◽  
Author(s):  
Christina Hipfinger ◽  
Ramesh Subbiah ◽  
Anthony Tahayeri ◽  
Avathamsa Athirasala ◽  
Sivaporn Horsophonphong ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
3D Printing ◽  
Three Dimensional ◽  
Tissue Healing ◽  
Wide Range ◽  
Biomaterial Scaffolds ◽  
Specialized Equipment ◽  
Intuitive Concept ◽  
Biological Performance

AbstractBiomaterial scaffolds have served as the foundation of tissue engineering and regenerative medicine. However, scaffold systems are often difficult to scale in size or shape in order to fit defect-specific dimensions, and thus provide only limited spatiotemporal control of therapeutic delivery and host tissue responses. Here, a lithography-based three-dimensional (3D) printing strategy is used to fabricate a novel miniaturized modular LEGO-like cage scaffold system, which can be assembled and scaled manually with ease. Scalability is based on an intuitive concept of stacking modules, like conventional LEGO blocks, allowing for literally thousands of potential geometric configurations, and without the need for specialized equipment. Moreover, the modular hollow-cage design allows each unit to be loaded with biologic cargo of different compositions, thus enabling controllable and easy patterning of therapeutics within the material in 3D. In summary, the concept of miniaturized cage designs with such straight-forward assembly and scalability, as well as controllable loading properties, is a flexible platform that can be extended to a wide range of materials for improved biological performance.TOC3D printed LEGO-like hollow microcages can be easily assembled, adjoined, and stacked-up to suit the complexity of defect tissues; aid spatial loading of cells and biomolecules; instruct cells migration three-dimensionally; and facilitate cell invasion and neovascularization in-vivo, thus accelerating the process of tissue healing and new tissue formation.

scholarly journals Three-Dimensional Bioprinting Nanotechnologies towards Clinical Application of Stem Cells and Their Secretome in Salivary Gland Regeneration

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Joao N. Ferreira ◽  
Sasitorn Rungarunlert ◽  
Ganokon Urkasemsin ◽  
Christabella Adine ◽  
Glauco R. Souza
Keyword(s):  
Salivary Gland ◽  
Ex Vivo ◽  
Three Dimensional ◽  
Cell Types ◽  
Poor Quality ◽  
Saliva Secretion ◽  
Wide Range ◽  
Salivary Gland Regeneration

Salivary gland (SG) functional damage and severe dry mouth (or xerostomia) are commonly observed in a wide range of medical conditions from autoimmune to metabolic disorders as well as after radiotherapy to treat specific head and neck cancers. No effective therapy has been developed to completely restore the SG functional damage on the long-term and reverse the poor quality of life of xerostomia patients. Cell- and secretome-based strategies are currently being tested in vitro and in vivo for the repair and/or regeneration of the damaged SG using (1) epithelial SG stem/progenitor cells from salispheres or explant cultures as well as (2) nonepithelial stem cell types and/or their bioactive secretome. These strategies will be the focus of our review. Herein, innovative 3D bioprinting nanotechnologies for the generation of organotypic cultures and SG organoids/mini-glands will also be discussed. These bioprinting technologies will allow researchers to analyze the secretome components and extracellular matrix production, as well as their biofunctional effects in 3D mini-glands ex vivo. Improving our understanding of the SG secretome is critical to develop effective secretome-based therapies towards the regeneration and/or repair of all SG compartments for proper restoration of saliva secretion and flow into the oral cavity.

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