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1.
Int. j. morphol ; 41(4): 1107-1111, ago. 2023. tab
Artigo em Inglês | LILACS | ID: biblio-1514329

RESUMO

SUMMARY: The aim of this research is to introduce the ideal lecture technique to the literature by explaining the anatomy of the skeletal system using the classical method, video-assisted method and 3D imaging techniques. The research was carried out with 180 students. The number of samples was determined by power analysis (a=0.05,b=0.20, effect size=0.25). Participants were pre-screened and divided into 4 groups with the closest group mean (group 1: control group: the group that did not take anatomy lessons, group 2: video-assisted anatomy education, group 3: 3D anatomy course, group 4: classical anatomy education group). The courses in the training groups were organised as 4 hours/day, 2 days/week for 5 weeks. At the end of the course, the students were re-examined and scaled to determine the difference in scores and self-efficacy between the groups. A one-way ANOVA test was performed because the data were normally distributed when comparing between groups. The mean scores were calculated as group 1=30.22±6.24, group 2=39.02±9.15, group 3=49.77±9.20 and group 4=59.28±8.95. In the post hoc comparison, in pairwise comparisons between all groups, the differences were highly significant (pgroup 3>group 2>group 1 (p<0.001). According to the results of this study, the laboratory method in skeletal anatomy teaching is the best alternative to 3D anatomy teaching.


El objetivo de esta investigación es introducir la técnica de lectura ideal en la literatura, explicando la anatomía del sistema esquelético, utilizando el método clásico, el método asistido por video y las técnicas de imágenes en 3D. La investigación se llevó a cabo con 180 estudiantes. El número de muestras se determinó mediante análisis de potencia (a=0,05, b=0,20, tamaño del efecto=0,25). Los participantes fueron preseleccionados y divididos en 4 grupos con la media de grupo más cercana (grupo 1: grupo de control: el grupo que no tomó lecciones de anatomía, grupo 2: educación de anatomía asistida por video, grupo 3: curso de anatomía 3D, grupo 4: grupo de educación en anatomía clásica). Los cursos en los grupos de formación se organizaron con 4 horas/día, 2 días/semana durante 5 semanas. Al final del curso, los estudiantes fueron reexaminados y escalados para determinar la diferencia en puntajes y autoeficacia entre los grupos. Se realizó una prueba de ANOVA de una vía debido a que los datos se distribuyeron normalmente al comparar entre grupos. Las puntuaciones medias se calcularon como grupo 1=30,22±6,24, grupo 2=39,02±9,15, grupo 3=49,77±9,20 y grupo 4=59,28±8,95. En la comparación post hoc, en comparaciones por pares entre todos los grupos, las diferencias fueron altamente significativas (pgrupo 3>grupo 2>grupo 1 (p<0,001). Según los resultados de este estudio, el método de laboratorio en la enseñanza de la anatomía esquelética es la mejor alternativa a la enseñanza de la anatomía en 3D.


Assuntos
Humanos , Imageamento Tridimensional , Educação Médica/métodos , Técnicas e Procedimentos Assistidos por Vídeo , Anatomia/educação , Aprendizagem , Sistema Musculoesquelético/anatomia & histologia , Inquéritos e Questionários , Análise de Variância , Avaliação Educacional , Sistema Musculoesquelético/diagnóstico por imagem
2.
Nature ; 614(7946): 102-107, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36697827

RESUMO

Living amphibians (Lissamphibia) include frogs and salamanders (Batrachia) and the limbless worm-like caecilians (Gymnophiona). The estimated Palaeozoic era gymnophionan-batrachian molecular divergence1 suggests a major gap in the record of crown lissamphibians prior to their earliest fossil occurrences in the Triassic period2-6. Recent studies find a monophyletic Batrachia within dissorophoid temnospondyls7-10, but the absence of pre-Jurassic period caecilian fossils11,12 has made their relationships to batrachians and affinities to Palaeozoic tetrapods controversial1,8,13,14. Here we report the geologically oldest stem caecilian-a crown lissamphibian from the Late Triassic epoch of Arizona, USA-extending the caecilian record by around 35 million years. These fossils illuminate the tempo and mode of early caecilian morphological and functional evolution, demonstrating a delayed acquisition of musculoskeletal features associated with fossoriality in living caecilians, including the dual jaw closure mechanism15,16, reduced orbits17 and the tentacular organ18. The provenance of these fossils suggests a Pangaean equatorial origin for caecilians, implying that living caecilian biogeography reflects conserved aspects of caecilian function and physiology19, in combination with vicariance patterns driven by plate tectonics20. These fossils reveal a combination of features that is unique to caecilians alongside features that are shared with batrachian and dissorophoid temnospondyls, providing new and compelling evidence supporting a single origin of living amphibians within dissorophoid temnospondyls.


Assuntos
Anfíbios , Anuros , Fósseis , Filogenia , Urodelos , Animais , Anfíbios/anatomia & histologia , Anuros/anatomia & histologia , Arizona , Urodelos/anatomia & histologia , Órbita/anatomia & histologia , Arcada Osseodentária/anatomia & histologia , Sistema Musculoesquelético/anatomia & histologia
3.
Anat Rec (Hoboken) ; 306(7): 1804-1823, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36647300

RESUMO

Megaraptora is a group of enigmatic, carnivorous non-avian theropod dinosaurs from the Cretaceous of Asia, Australia, and especially South America. Perhaps the most striking aspect of megaraptoran morphology is the large, robustly constructed forelimb that, in derived members of the clade, terminates in a greatly enlarged manus with hypertrophied, raptorial unguals on the medialmost two digits and a substantially smaller ungual on digit III. The unique forelimb anatomy of megaraptorans was presumably associated with distinctive functional specializations; nevertheless, its paleobiological significance has not been extensively explored. Here we draw from observations of the pectoral girdle and forelimb skeletons of Megaraptora and myological assessments of other archosaurian taxa to provide a comprehensive reconstruction of the musculature of this anatomical region in these singular theropods. Many muscle attachment sites on megaraptoran forelimb bones are remarkably well developed, which in turn suggests that the muscles themselves were functionally significant and important to the paleobiology of these theropods. Furthermore, many of these attachments became increasingly pronounced through megaraptoran evolutionary history, being substantially better developed in derived taxa such as Australovenator wintonensis and especially Megaraptor namunhuaiquii than in early branching forms such as Fukuiraptor kitadaniensis. When considered alongside previous range of motion hypotheses for Australovenator, our results indicate that megaraptorans possessed a morphologically and functionally specialized forelimb that was capable of complex movements. Notable among these were extensive extension and flexion, particularly in the highly derived manus, as well as enhanced humeral protraction, attributes that very probably aided in prey capture.


Assuntos
Dinossauros , Sistema Musculoesquelético , Animais , Dinossauros/anatomia & histologia , Extremidade Superior/anatomia & histologia , Evolução Biológica , Membro Anterior/anatomia & histologia , Sistema Musculoesquelético/anatomia & histologia , Fósseis
4.
J Biomech Eng ; 145(4)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36346198

RESUMO

Reliably and accurately estimating joint/segmental kinematics from optical motion capture data has remained challenging. Studies objectively characterizing human movement patterns have typically involved inverse kinematics and inverse dynamics techniques. Subsequent research has included scaled cadaver-based musculoskeletal (MSK) modeling for noninvasively estimating joint and muscle loads. As one of the ways to enhance confidence in the validity of MSK model predictions, the kinematics from the preceding step that drives such a model needs to be checked for agreement or compared with established/widely used models. This study rigorously compares the upper extremity (UE) joint kinematics calculated by the Dutch Shoulder Model implemented in the AnyBody Managed Model Repository (involving multibody kinematics optimization (MKO)) with those estimated by the Vicon Plug-in Gait model (involving single-body kinematics optimization (SKO)). Ten subjects performed three trials of (different types of) reaching tasks in a three-dimensional marker-based optical motion capture laboratory setting. Joint angles, processed marker trajectories, and reconstruction residuals corresponding to both models were compared. Scatter plots and Bland-Altman plots were used to assess the agreement between the two model outputs. Results showed the largest differences between the two models for shoulder, followed by elbow and wrist, with all root-mean-squared differences less than 10 deg (although this limit might be unacceptable for clinical use). Strong-to-excellent Spearman's rank correlation coefficients were found between the two model outputs. The Bland-Altman plots showed a good agreement between most of the outputs. In conclusion, results indicate that these two models with different kinematic algorithms broadly agree with each other, albeit with few key differences.


Assuntos
Modelos Anatômicos , Sistema Musculoesquelético , Extremidade Superior , Humanos , Extremidade Superior/anatomia & histologia , Cadáver , Sistema Musculoesquelético/anatomia & histologia , Fenômenos Biomecânicos , Captura de Movimento
5.
Nat Commun ; 13(1): 7684, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36539437

RESUMO

Morphology of keratinised toe pads and foot scales, hinging of foot joints and claw shape and size all inform the grasping ability, cursoriality and feeding mode of living birds. Presented here is morphological evidence from the fossil feet of early theropod flyers. Foot soft tissues and joint articulations are qualitatively assessed using laser-stimulated fluorescence. Pedal claw shape and size are quantitatively analysed using traditional morphometrics. We interpret these foot data among existing evidence to better understand the evolutionary ecology of early theropod flyers. Jurassic flyers like Anchiornis and Archaeopteryx show adaptations suggestive of relatively ground-dwelling lifestyles. Early Cretaceous flyers then diversify into more aerial lifestyles, including generalists like Confuciusornis and specialists like the climbing Fortunguavis. Some early birds, like the Late Jurassic Berlin Archaeopteryx and Early Cretaceous Sapeornis, show complex ecologies seemingly unique among sampled modern birds. As a non-bird flyer, finding affinities of Microraptor to a more specialised raptorial lifestyle is unexpected. Its hawk-like characteristics are rare among known theropod flyers of the time suggesting that some non-bird flyers perform specialised roles filled by birds today. We demonstrate diverse ecological profiles among early theropod flyers, changing as flight developed, and some non-bird flyers have more complex ecological roles.


Assuntos
Dinossauros , Sistema Musculoesquelético , Animais , Evolução Biológica , Fósseis , Sistema Musculoesquelético/anatomia & histologia , Adaptação Fisiológica , Dinossauros/anatomia & histologia , Filogenia
6.
Sci Rep ; 12(1): 2848, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181716

RESUMO

We clarified the specific micrometric arrangement and nanometric structure of the radiolarian crystalline spines that are not a simple single crystal. A body of the celestite (SrSO4) skeleton of acantharian Acanthometra cf. multispina (Acanthometridae) composed of 20 radial spines having four blades was characterized using microfocus X-ray computed tomography. The regular arrangement of three types of spines was clarified with the connection of the blades around the root of each spine. The surface of the spines was covered with a chitin-based organic membrane to prevent from dissolution in seawater. In the nanometric scale, the mesocrystalline structure that consists of nanoscale grains having distorted single-crystal nature was revealed using scanning- and transmission electron microscopies, electron diffraction, and Raman spectroscopy. The acantharian skeletons have a crystallographically controlled architecture that is covered with a protective organic membrane. These facts are important for penetrating the nature of biogenic minerals.


Assuntos
Rhizaria/ultraestrutura , Esqueleto/anatomia & histologia , Microscopia Eletrônica de Transmissão , Minerais/metabolismo , Sistema Musculoesquelético/anatomia & histologia , Sistema Musculoesquelético/ultraestrutura , Filogenia , Água do Mar , Esqueleto/ultraestrutura , Análise Espectral Raman
7.
Nat Commun ; 12(1): 6707, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795247

RESUMO

Bioelectronic interfaces have been extensively investigated in recent years and advances in technology derived from these tools, such as soft and ultrathin sensors, now offer the opportunity to interface with parts of the body that were largely unexplored due to the lack of suitable tools. The musculoskeletal system is an understudied area where these new technologies can result in advanced capabilities. Bones as a sensor and stimulation location offer tremendous advantages for chronic biointerfaces because devices can be permanently bonded and provide stable optical, electromagnetic, and mechanical impedance over the course of years. Here we introduce a new class of wireless battery-free devices, named osseosurface electronics, which feature soft mechanics, ultra-thin form factor and miniaturized multimodal biointerfaces comprised of sensors and optoelectronics directly adhered to the surface of the bone. Potential of this fully implanted device class is demonstrated via real-time recording of bone strain, millikelvin resolution thermography and delivery of optical stimulation in freely-moving small animal models. Battery-free device architecture, direct growth to the bone via surface engineered calcium phosphate ceramic particles, demonstration of operation in deep tissue in large animal models and readout with a smartphone highlight suitable characteristics for exploratory research and utility as a diagnostic and therapeutic platform.


Assuntos
Fontes de Energia Elétrica , Fenômenos Eletromagnéticos , Eletrônica/instrumentação , Fenômenos Fisiológicos Musculoesqueléticos , Termografia/instrumentação , Tecnologia sem Fio/instrumentação , Animais , Eletrônica/métodos , Masculino , Microscopia Eletrônica de Varredura , Sistema Musculoesquelético/anatomia & histologia , Sistema Musculoesquelético/ultraestrutura , Redes Neurais de Computação , Ratos Sprague-Dawley , Estresse Mecânico , Termografia/métodos , Microtomografia por Raio-X/métodos
8.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 843-852, Jul.-Aug. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285273

RESUMO

Maneuvers to activate the equine's core can make a difference in their physical and psychic health. Although these activities are recommended and practiced, there is little research proving their effectiveness. This article aims to describe, through surface electromyography, the occurrences, durations and sequences activity of longissimus dorsi, rectus abdominis and gluteus medius during thoracolumbar flexion (TLF), lumbar and lumbosacral flexion (LLSF), global flexion (GF), which is the combination of TLF and LLSF, and tail traction (TT). Seven healthy adult horses of three different breeds performed five repetitions of these movements for five seconds (sec). Electromyographic activity was captured with non-invasive superficial sensors positioned in the skin regions covering these muscles. The sequence was performed once per animal, muscle activity captured by surface electromyography, data from two replicates of each animal were selected, analyzed on matLab software and data tabulation were described during each maneuver. These maneuvers provoked punctual and transient activation of muscles mentioned above, confirming the ability to activate equine core muscles. However, responses were not standardized, which means there were variations of occurrence, duration and sequence, suggesting that for practical application of those maneuvers it is necessary to perform more repetitions with longer durations to activate more muscles.(AU)


Manobras para ativação da musculatura do core equino podem ser diferenciais para saúde física e psíquica dos animais, sendo recomendadas e praticadas, mas existem poucas pesquisas comprovando a eficácia delas. Este artigo tem como objetivo descrever, por meio da eletromiografia de superfície, as ocorrências, as durações e as sequências temporais da atividade muscular do longuíssimo dorsal, do reto abdominal e do glúteo médio durante a realização das manobras de flexão toracolombar, flexão lombar e lombossacra, flexão global (toracolombar e lombossacra) e tração de cauda. Para isso, sete equinos adultos e hígidos de três raças realizaram esses quatro movimentos clássicos para ativar o core equino, com cinco repetições e manutenção do estímulo reflexivo por cinco segundos. Durante a realização, a atividade eletromiográfica foi capturada com a utilização de sensores superficiais posicionados de forma não invasiva em regiões cutâneas referentes a cada músculo. O protocolo completo de manobras foi realizado uma vez por cada animal enquanto a atividade muscular era capturada. Posteriormente, duas repetições de cada animal foram triadas e submetidas ao software matLab para análise. Com base na tabulação dos dados, foram descritas as variáveis eletromiográficas de presença ou ausência de ativação muscular, a duração média dos picos eletromiográficos superiores ao RMS (root mean square) e a sequência da atividade muscular observada durante cada manobra. Essas manobras provocaram ativações pontuais e transitórias nos três músculos, o que confirma a capacidade de excitar músculos do core equino. Contudo, as respostas não foram padronizadas, sugerindo que, na prática dessa atividade, devem-se realizar mais repetições com durações superiores a cinco segundos, a fim de se buscarem maiores ativações.(AU)


Assuntos
Animais , Amplitude de Movimento Articular/fisiologia , Técnicas de Exercício e de Movimento/veterinária , Exercícios de Alongamento Muscular , Cavalos/fisiologia , Sistema Musculoesquelético/anatomia & histologia , Eletromiografia/veterinária , Exercício de Aquecimento
9.
PLoS One ; 16(6): e0252355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34081728

RESUMO

Late Jurassic deposits across Europe have yielded a rich fauna of extinct turtles. Although many of these turtles are recovered from marine deposits, it is unclear which of these taxa are habitually marine and which may be riverine species washed into nearby basins, as adaptations to open marine conditions are yet to be found. Two new fossils from the Late Jurassic of Germany provide unusually strong evidence for open marine adaptations. The first specimen is a partial shell and articulated hind limb from the Late Jurassic (early Tithonian) platy limestones of Schernfeld near Eichstätt, which preserves the integument of the hind limb as an imprint. The skin is fully covered by flat, polygonal scales, which stiffen the pes into a paddle. Although taxonomic attribution is not possible, similarities are apparent with Thalassemys. The second specimen is a large, articulated skeleton with hypertrophied limbs referable to Thalassemys bruntrutana from the Late Jurassic (early Late Kimmeridgian) platy limestone of Wattendorf, near Bamberg. Even though the skin is preserved as a phosphatic film, the scales are not preserved. This specimen can nevertheless be inferred to have had paddles stiffened by scales based on the pose in which they are preserved, the presence of epibionts between the digits, and by full morphological correspondence to the specimen from Schernfeld. An analysis of scalation in extant turtles demonstrated that elongate flippers stiffed by scales are a marine adaptation, in contrast to the elongate but flexible flippers of riverine turtles. Phylogenetic analysis suggests that Thalassemys bruntrutana is referable to the mostly Late Jurassic turtle clade Thalassochelydia. The marine adapted flippers of this taxon therefore evolved convergently with those of later clades of marine turtles. Although thalassochelydian fossils are restricted to Europe, with one notable exception from Argentina, their open marine adaptations combined with the interconnectivity of Jurassic oceans predict that the clade must have been even more wide-spread during that time.


Assuntos
Extremidades/anatomia & histologia , Fósseis/anatomia & histologia , Tartarugas/anatomia & histologia , Adaptação Fisiológica/fisiologia , Nadadeiras de Animais/anatomia & histologia , Animais , Fenômenos Biomecânicos/fisiologia , Carbonato de Cálcio/análise , Alemanha , Sistema Musculoesquelético/anatomia & histologia , Filogenia
10.
PLoS Comput Biol ; 17(5): e1008594, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34010288

RESUMO

The central nervous system of humans and other animals modulates spinal cord activity to achieve several locomotion behaviors. Previous neuromechanical models investigated the modulation of human gait changing selected parameters belonging to CPGs (Central Pattern Generators) feedforward oscillatory structures or to feedback reflex circuits. CPG-based models could replicate slow and fast walking by changing only the oscillation's properties. On the other hand, reflex-based models could achieve different behaviors through optimizations of large dimensional parameter spaces. However, they could not effectively identify individual key reflex parameters responsible for gait characteristics' modulation. This study investigates which reflex parameters modulate the gait characteristics through neuromechanical simulations. A recently developed reflex-based model is used to perform optimizations with different target behaviors on speed, step length, and step duration to analyze the correlation between reflex parameters and their influence on these gait characteristics. We identified nine key parameters that may affect the target speed ranging from slow to fast walking (0.48 and 1.71 m/s) as well as a large range of step lengths (0.43 and 0.88 m) and step duration (0.51, 0.98 s). The findings show that specific reflexes during stance significantly affect step length regulation, mainly given by positive force feedback of the ankle plantarflexors' group. On the other hand, stretch reflexes active during swing of iliopsoas and gluteus maximus regulate all the gait characteristics under analysis. Additionally, the results show that the hamstrings' group's stretch reflex during the landing phase is responsible for modulating the step length and step duration. Additional validation studies in simulations demonstrated that the modulation of identified reflexes is sufficient to regulate the investigated gait characteristics. Thus, this study provides an overview of possible reflexes involved in modulating speed, step length, and step duration of human gaits.


Assuntos
Marcha/fisiologia , Locomoção/fisiologia , Modelos Neurológicos , Fenômenos Biomecânicos , Biologia Computacional , Simulação por Computador , Humanos , Modelos Anatômicos , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Fenômenos Fisiológicos Musculoesqueléticos , Sistema Musculoesquelético/anatomia & histologia , Sistema Musculoesquelético/inervação , Desempenho Psicomotor/fisiologia , Reflexo de Estiramento/fisiologia , Caminhada/fisiologia
11.
Nat Commun ; 12(1): 1525, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750763

RESUMO

Anolis lizards originated in continental America but have colonized the Greater Antillean islands and recolonized the mainland, resulting in three major groups (Primary and Secondary Mainland and Greater Antillean). The adaptive radiation in the Greater Antilles has famously resulted in the repeated evolution of ecomorphs. Yet, it remains poorly understood to what extent this island radiation differs from diversification on the mainland. Here, we demonstrate that the evolutionary modularity between girdles and limbs is fundamentally different in the Greater Antillean and Primary Mainland Anolis. This is consistent with ecological opportunities on islands driving the adaptive radiation along distinct evolutionary trajectories. However, Greater Antillean Anolis share evolutionary modularity with the group that recolonized the mainland, demonstrating a persistent phylogenetic inertia. A comparison of these two groups support an increased morphological diversity and faster and more variable evolutionary rates on islands. These macroevolutionary trends of the locomotor skeleton in Anolis illustrate that ecological opportunities on islands can have lasting effects on morphological diversification.


Assuntos
Evolução Biológica , Lagartos/anatomia & histologia , Lagartos/classificação , Filogenia , Esqueleto/anatomia & histologia , Animais , Região do Caribe , Extremidades , Feminino , Ilhas , Masculino , Sistema Musculoesquelético/anatomia & histologia , Filogeografia , Especificidade da Espécie
12.
J Morphol ; 282(2): 205-216, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33159480

RESUMO

Basket stars, that is, Ophiuroidea in Echinodermata, exhibit distinctive morphological characteristics with their complicatedly branched arms that can regenerate immediately after mutilation. Although, in brittle stars, that is, ophiuroids with nonbranched arms, the arm regeneration process following accidental trauma or autotomy have been morphologically and histologically observed in several species, few studies have so far been carried out on the regeneration of branched arms in basket stars. In this study, the developmental and morphological features of arm regeneration in Astrocladus dofleini (Gorgonocephalidae, Euryalida, Euryophiurida), one of the most common basket star species in Japanese waters, was anatomically and histologically investigated. Results clearly showed the following phases during the arm regeneration: (a) repair phase, (b) early regenerative phase, (c) intermediate regenerative phase, (d) advanced regenerative Phase I, and (e) advanced regenerative Phase II. The morphogenetic process during the arm regeneration in the basket star showed similar patterns to those of nonbranched arms observed in other ophiuroids. However, differences were also seen between the two ophiuroid types, that is, there were some developmental features specific to the basket star. In the early regenerative phase, branching of coelomic cavities was observed prior to the formation of other tissues, probably inducing the later morphogenesis of branched arms. In addition, hard skeletal ossicles form rapidly at the advanced regenerative Phase II. These developmental features may have led the evolution of bizarre morphologies seen in basket stars, probably contributing to the adaptation to shallow waters from deep-sea habitats.


Assuntos
Equinodermos/anatomia & histologia , Equinodermos/fisiologia , Morfogênese , Animais , Equinodermos/citologia , Sistema Musculoesquelético/anatomia & histologia , Regeneração
13.
Sci Rep ; 10(1): 17655, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077752

RESUMO

Trajectory optimization with musculoskeletal models can be used to reconstruct measured movements and to predict changes in movements in response to environmental changes. It enables an exhaustive analysis of joint angles, joint moments, ground reaction forces, and muscle forces, among others. However, its application is still limited to simplified problems in two dimensional space or straight motions. The simulation of movements with directional changes, e.g. curved running, requires detailed three dimensional models which lead to a high-dimensional solution space. We extended a full-body three dimensional musculoskeletal model to be specialized for running with directional changes. Model dynamics were implemented implicitly and trajectory optimization problems were solved with direct collocation to enable efficient computation. Standing, straight running, and curved running were simulated starting from a random initial guess to confirm the capabilities of our model and approach: efficacy, tracking and predictive power. Altogether the simulations required 1 h 17 min and corresponded well to the reference data. The prediction of curved running using straight running as tracking data revealed the necessity of avoiding interpenetration of body segments. In summary, the proposed formulation is able to efficiently predict a new motion task while preserving dynamic consistency. Hence, labor-intensive and thus costly experimental studies could be replaced by simulations for movement analysis and virtual product design.


Assuntos
Corrida/fisiologia , Humanos , Imageamento Tridimensional , Modelos Biológicos , Movimento/fisiologia , Fenômenos Fisiológicos Musculoesqueléticos , Sistema Musculoesquelético/anatomia & histologia
15.
Orthop Surg ; 12(6): 1547-1566, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32930465

RESUMO

Evaluation of the biomechanical properties of soft tissues by measuring the stress-strain relationships has been the focus of numerous investigations. The accuracy of stress depends, in part, upon the determination of the cross-sectional area (CSA). However, the complex geometry and pliability of soft tissues, especially ligaments and tendons, make it difficult to obtain accurate CSA, and the development of CSA measurement methods of soft tissues continues. Early attempts to determine the CSA of soft tissues include gravimetric method, geometric approximation technique, area micrometer method, and microtomy technique. Since 1990, a series of new methods have emerged, including medical imaging techniques (e.g. magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound imaging (USI)), laser techniques (e.g. the laser micrometer method, the linear laser scanner (LLS) technique, and the laser reflection system (LRS) method), molding techniques, and three-dimensional (3D) scanning techniques.


Assuntos
Fenômenos Fisiológicos Musculoesqueléticos , Sistema Musculoesquelético/anatomia & histologia , Sistema Musculoesquelético/diagnóstico por imagem , Fenômenos Biomecânicos , Humanos
16.
Biomech Model Mechanobiol ; 19(4): 1169-1185, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32676934

RESUMO

Many biomedical, orthopaedic, and industrial applications are emerging that will benefit from personalized neuromusculoskeletal models. Applications include refined diagnostics, prediction of treatment trajectories for neuromusculoskeletal diseases, in silico design, development, and testing of medical implants, and human-machine interfaces to support assistive technologies. This review proposes how physics-based simulation, combined with machine learning approaches from big data, can be used to develop high-fidelity personalized representations of the human neuromusculoskeletal system. The core neuromusculoskeletal model features requiring personalization are identified, and big data/machine learning approaches for implementation are presented together with recommendations for further research.


Assuntos
Aprendizado de Máquina , Modelos Anatômicos , Sistema Musculoesquelético/anatomia & histologia , Sistema Nervoso/anatomia & histologia , Fenômenos Biomecânicos , Humanos , Imageamento Tridimensional
17.
Anat Histol Embryol ; 49(5): 656-678, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32639627

RESUMO

The cardiovascular system is the first functional organ in the embryo, and its blood vessels form a widespread conductive network within the organism. Blood vessels develop de novo, by the differentiation of endothelial progenitor cells (vasculogenesis) or by angiogenesis, which is the formation of new blood vessels from existing ones. This review presents an overview of the current knowledge on physiological and pathological angiogenesis in the horse including studies on equine endothelial cells. Principal study fields in equine angiogenesis research were identified: equine endothelial progenitor cells; equine endothelial cells and angiogenesis (heterogeneity, markers and assessment); endothelial regulatory molecules in equine angiogenesis; angiogenesis research in equine reproduction (ovary, uterus, placenta and conceptus, testis); angiogenesis research in pathological conditions (tumours, ocular pathologies, equine wound healing, musculoskeletal system and laminitis). The review also includes a table that summarizes in vitro studies on equine endothelial cells, either describing the isolation procedure or using previously isolated endothelial cells. A particular challenge of the review was that results published are fragmentary and sometimes even contradictory, raising more questions than they answer. In conclusion, angiogenesis is a major factor in several diseases frequently occurring in horses, but relatively few studies focus on angiogenesis in the horse. The challenge for the future is therefore to continue exploring new therapeutic angiogenesis strategies for horses to fill in the missing pieces of the puzzle.


Assuntos
Sistema Cardiovascular/embriologia , Sistema Cardiovascular/crescimento & desenvolvimento , Células Progenitoras Endoteliais/fisiologia , Doenças dos Cavalos/patologia , Cavalos/embriologia , Cavalos/crescimento & desenvolvimento , Animais , Oftalmopatias/patologia , Oftalmopatias/veterinária , Feminino , Casco e Garras/irrigação sanguínea , Casco e Garras/patologia , Masculino , Sistema Musculoesquelético/anatomia & histologia , Sistema Musculoesquelético/irrigação sanguínea , Neoplasias/irrigação sanguínea , Neoplasias/veterinária , Ovário/irrigação sanguínea , Ovário/fisiologia , Placenta/fisiologia , Gravidez , Reprodução , Testículo/irrigação sanguínea , Útero/irrigação sanguínea , Útero/fisiologia , Cicatrização/fisiologia
19.
Am J Phys Anthropol ; 173(1): 190-199, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32602120

RESUMO

OBJECTIVES: The present study tests the effectiveness of entheseal robusticity (ER) as a potential predictor of adult age-at-death by applying multiple regression models to a large contemporary identified skeletal sample. MATERIALS AND METHODS: ER was recorded for 23 bilateral postcranial entheses on 481 adult individuals (271 females and 210 males) from the Frassetto identified skeletal collection of Sassari (Italy), following the method of Mariotti et al. 2007. ER scores were used as predictors in multiple regression analyses with age as the dependent variable; the performance of the resulting models was tested through standard error of estimate, the correlation coefficient between predicted and documented age, and the percentage of correctly classified individuals. RESULTS: ER show a higher correlation with age in females, resulting in more accurate estimates when compared with those obtained for males. Age-at-death is overestimated for male individuals under 45 years old and underestimated for older individuals. Regression models including a reduced set of ER sites result in better estimates compared with those using the complete set of variables. DISCUSSION: Results suggest the potential usefulness of ER for the estimation of age, especially for female skeletal remains. If used with caution, ER may be a valid complement to existing methods for the reconstruction of the biological profile of skeletal remains of archaeological and forensic interest.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Sistema Musculoesquelético/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropologia Física , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Arq. ciências saúde UNIPAR ; 24(2): 113-116, maio-ago. 2020.
Artigo em Português | LILACS | ID: biblio-1116374

RESUMO

O estudo da Anatomia Humana (AH) é parte integrante e de relevância inquestionável na graduação dos cursos da saúde. Com a constante redução na carga horária destinada à AH e diante dos debates sobre os novos métodos de ensino, o uso do código de quick response (código QR) se mostrou promissor. Nesse sentido, foi desenvolvido no Departamento de Anatomia da Universidade Estadual de Londrina (UEL) o processo de catalogação das estruturas anatômicas com o uso do código QR, sendo nosso objetivo relatar esta experiência. Neste processo, as estruturas dissecadas no Laboratório de Anatomia da UEL foram catalogadas com base em uma planilha contendo a correlação entre estruturas e números e, as informações de cada estrutura transcritas em um código QR através de um gerador eletrônico, sendo então impresso, plastificado e anexado à peça anatômica. As marcações foram realizadas por meio da sutura de etiquetas enumeradas. Dentro da discussão dos métodos alternativos de ensino há como exemplos a plastinação, a projeção em três dimensões e a prospecção. Em destaque neste relato, o uso do código QR mostrou-se como uma alternativa válida na agregação de conhecimento nos currículos acadêmicos. Por meio das atividades empreendidas no processo de catalogação, foi possível, além da aquisição de mais tempo dedicado ao conhecimento teórico-prático em AH, ampliar a independência no estudo e no desenvolvimento de pesquisas. Dessa forma, tem-se a oportunidade de se expandir as análises voltadas ao ensino da AH e aos novos métodos de aprendizado.


The study of human anatomy is a relevant part of the curriculum of health course graduation students. Given the constant reduction of hours destinated to the study of Anatomy and the debates regarding new teaching methods, the use of the Quick Response Code (QR code) has shown to be promising. Therefore, the Anatomy Department at the State University of Londrina (UEL) has developed a cataloging process concerning anatomical structures with the application of QR code, and this paper has the purpose of reporting on such experience. In the process, the structures dissected in UEL's Anatomy Laboratory were cataloged based on a spreadsheet which contained the correlation between these structures and numbers; the information regarding each structure was then transcribed into a QR code using a digital generator, with posterior printing, lamination and attachment to the body part. The labels were made by sewing the numbered tags onto the structures. Within the discussion regarding alternative teaching methods, examples can be given regarding lamination, three-dimension projection and prospection. The use of the QR code has proven to be a valid alternative in aggregating knowledge to academic curriculum. Through the activities performed in the process of cataloging, it was possible not only to dedicate more time to the theorical and practical learning of human anatomy, but also to increase the independence in studying and developing research. Furthermore, there is an opportunity to expand the analysis directed toward human anatomy teaching and toward new learning methods.


Assuntos
Humanos , Tecnologia Educacional/métodos , Educação de Graduação em Medicina/métodos , Anatomia/educação , Locomoção , Sistema Musculoesquelético/anatomia & histologia , Materiais de Ensino , Tecnologia Educacional/instrumentação , Dissecação/métodos
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