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.

Kinematics of the Ankle/Foot Complex: Plantarflexion and Dorsiflexion

Foot & Ankle ◽  
1989 ◽  
Vol 9 (4) ◽  
pp. 194-200 ◽  
Author(s):  
Arne Lundberg ◽  
Ian Goldie ◽  
Bo Kalin ◽  
Göran Selvik
Keyword(s):  
Plantar Flexion ◽  
Three Dimensional ◽  
Substantial Contribution ◽  
Neutral Position ◽  
Transverse Axis ◽  
Talocrural Joint ◽  
Foot Kinematics ◽  
Talocalcaneal Joint ◽  
Axis Rotation

In an in vivo investigation of eight healthy volunteers, three dimensional ankle/foot kinematics were analyzed by roentgen stereophotogrammetry in 10° steps of motion from 30° of plantar flexion to 30° of dorsiflexion of the foot. The study included all of the joints between the tibia and the first metatarsal, as well as the talocalcaneal joint, and was performed under full body load. Although the talocrural joint was found to account for most of the rotation around the transverse axis occurring from 30° of plantar flexion to 30° of dorsiflexion, there was a substantial contribution from the joints of the arch. This was seen particularly in the input arc from 30° of plantar flexion to the neutral position, where the dorsiflexion motion of these joints amounted to 10% to 41% of the total transverse axis rotation.

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.

In vivo estimation of contraction velocity of human vastus lateralis muscle during “isokinetic” action

2000 ◽  
Vol 88 (3) ◽  
pp. 851-856 ◽  
Author(s):  
Y. Ichinose ◽  
Y. Kawakami ◽  
M. Ito ◽  
H. Kanehisa ◽  
T. Fukunaga
Keyword(s):  
Angular Velocity ◽  
Vastus Lateralis ◽  
Knee Extension ◽  
Vastus Lateralis Muscle ◽  
Shortening Velocity ◽  
Full Extension ◽  
Fascicle Length ◽  
Lateralis Muscle ◽  
Angular Velocities

To determine the shortening velocities of fascicles of the vastus lateralis muscle (VL) during isokinetic knee extension, six male subjects were requested to extend the knee with maximal effort at angular velocities of 30 and 150°/s. By using an ultrasonic apparatus, longitudinal images of the VL were produced every 30 ms during knee extension, and the fascicle length and angle of pennation were obtained from these images. The shortening fascicle length with extension of the knee (from 98 to 13° of knee angle; full extension = 0°) was greater (43 mm) at 30°/s than at 150°/s (35 mm). Even when the angular velocity remained constant during the isokinetic range of motion, the fascicle velocity was found to change from 39 to 77 mm/s at 150°/s and from 6 to 19 mm/s at 30°/s. The force exerted by a fascicle changed with the length of the fascicle at changing angular velocities. The peak values of fascicle force and velocity were observed at ∼90 mm of fascicle length. In conclusion, even if the angular velocity of knee extension is kept constant, the shortening velocity of a fascicle is dependent on the force applied to the muscle-tendon complex, and the phenomenon is considered to be caused mainly by the elongation of the elastic element (tendinous tissue).

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 Aquatic and terrestrial takeoffs require different hindlimb kinematics and muscle function in mallard ducks

2020 ◽  
Vol 223 (16) ◽  
pp. jeb223743
Author(s):  
Kari R. Taylor-Burt ◽  
Andrew A. Biewener
Keyword(s):  
Muscle Function ◽  
Muscle Power ◽  
Contractile Function ◽  
Shortening Velocity ◽  
Muscle Properties ◽  
Hindlimb Muscle ◽  
Wide Range ◽  
Hindlimb Kinematics ◽  
Metatarsophalangeal Joints

ABSTRACTMallard ducks are capable of performing a wide range of behaviors including nearly vertical takeoffs from both terrestrial and aquatic habitats. The hindlimb plays a key role during takeoffs from both media. However, because force generation differs in water versus on land, hindlimb kinematics and muscle function are likely modulated between these environments. Specifically, we hypothesize that hindlimb joint motion and muscle shortening are faster during aquatic takeoffs, but greater hindlimb muscle forces are generated during terrestrial takeoffs. In this study, we examined the hindlimb kinematics and in vivo contractile function of the lateral gastrocnemius (LG), a major ankle extensor and knee flexor, during takeoffs from water versus land in mallard ducks. In contrast to our hypothesis, we observed no change in ankle angular velocity between media. However, the hip and metatarsophalangeal joints underwent large excursions during terrestrial takeoffs but exhibited almost no motion during aquatic takeoffs. The knee extended during terrestrial takeoffs but flexed during aquatic takeoffs. Correspondingly, LG fascicle shortening strain, shortening velocity and pennation angle change were greater during aquatic takeoffs than during terrestrial takeoffs because of the differences in knee motion. Nevertheless, we observed no significant differences in LG stress or work, but did see an increase in muscle power output during aquatic takeoffs. Because differences in the physical properties of aquatic and terrestrial media require differing hindlimb kinematics and muscle function, animals such as mallards may be challenged to tune their muscle properties for movement across differing environments.

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.

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-PhysNet: Learning the Intuitive Physics of Non-Rigid Object Deformations

2018 ◽  
Author(s):  
Zhihua Wang ◽  
Stefano Rosa ◽  
Bo Yang ◽  
Sen Wang ◽  
Niki Trigoni ◽  
...  
Keyword(s):  
Real Time ◽  
Three Dimensional ◽  
Applied Force ◽  
Training Data ◽  
Shape Information ◽  
Wide Range ◽  
Intuitive Physics ◽  
Adversarial Training ◽  
Applied Forces ◽  
Partial View

The ability to interact and understand the environment is a fundamental prerequisite for a wide range of applications from robotics to augmented reality. In particular, predicting how deformable objects will react to applied forces in real time is a significant challenge. This is further confounded by the fact that shape information about encountered objects in the real world is often impaired by occlusions, noise and missing regions e.g. a robot manipulating an object will only be able to observe a partial view of the entire solid. In this work we present a framework, 3D-PhysNet, which is able to predict how a three-dimensional solid will deform under an applied force using intuitive physics modelling. In particular, we propose a new method to encode the physical properties of the material and the applied force, enabling generalisation over materials. The key is to combine deep variational autoencoders with adversarial training, conditioned on the applied force and the material properties.We further propose a cascaded architecture that takes a single 2.5D depth view of the object and predicts its deformation. Training data is provided by a physics simulator. The network is fast enough to be used in real-time applications from partial views. Experimental results show the viability and the generalisation properties of the proposed architecture.

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.

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