scholarly journals CAD modelling of the human femur taking into account the structure of the bone

2021 ◽  
Vol 343 ◽  
pp. 04010
Author(s):  
Andrei Horia Brănescu ◽  
Ioana-Codruţa Lebădă ◽  
Vlăduţ Mihuţ ◽  
Nenad Marjanovic ◽  
Milan Rackov
Keyword(s):  
Bone Structure ◽  
Anatomical Study ◽  
3D Models ◽  
Biomechanical Study ◽  
Heterogeneous Structure ◽  
Surgical Interventions ◽  
Human Femur ◽  
Great Utility ◽  
Cad Modelling

The use of 3D models of the human bone system has great utility in the biomechanical study, due to the fact that these structures cannot be analyzed or tested in vivo. Within this paper, taking into consideration its real bone structure, the human femur CAD modelling is established. Firstly, a preliminary anatomical study is done, in order to highlight the fact that the thigh bone is a heterogeneous structure, consisting of several entities with different mechanical characteristics. The modelling starts from a homogenous 3D model of the femur, from which, every single separate entity is designed and finally they are assembled within a single product assembly. Therefore, the final result ensures a complex CAD structure, able to get assigned different material properties, specific for each entity this modelling furtherly allows the characteristic pathological structures studies of the referred entity or to simulate specific surgical interventions.

scholarly journals Contributions regarding 3D modelling of biomechanics of the foot

2021 ◽  
Vol 343 ◽  
pp. 04009
Author(s):  
Nicolae Florin Cofaru ◽  
Andrei Horia Brănescu ◽  
Vesna Marjanovic ◽  
Mirko Blagojevic ◽  
Vlăduţ Mihuţ
Keyword(s):  
3D Models ◽  
3D Modelling ◽  
Biomechanical Study ◽  
Human Foot ◽  
Pathological Conditions ◽  
State Research ◽  
Foot Motion ◽  
Cad Modelling ◽  
Biomechanics Of The Foot ◽  
Educational Field

Within this paper, a detailed study is elaborated regarding the human foot during both orthostatic and gait, the main goal being to develop 3D models which are very useful in the foot motion and loading state research. In order to elaborate the accurate 3D modelling of the human foot assembly, a thorough biomechanical study is done. Such a study was required due to the fact of the high anatomical complexity of the motions within the foot, taking into consideration the 26 bones and 33 joints consisting it. The research aims the CAD modelling of the biomechanics of the healthy subjects alongside with predisposed pathological conditions. The resulting models will have important utility in both educational field and for further CAE approaches and studies.

scholarly journals Concurrent YAP/TAZ and SMAD signaling mediate vocal fold fibrosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ryosuke Nakamura ◽  
Nao Hiwatashi ◽  
Renjie Bing ◽  
Carina P. Doyle ◽  
Ryan C. Branski
Keyword(s):  
Vocal Fold ◽  
Vocal Folds ◽  
Nuclear Accumulation ◽  
Smad Pathway ◽  
Surgical Interventions ◽  
Smad Signaling ◽  
Iatrogenic Damage ◽  
Tgf Β1

AbstractVocal fold (VF) fibrosis is a major cause of intractable voice-related disability and reduced quality of life. Excision of fibrotic regions is suboptimal and associated with scar recurrence and/or further iatrogenic damage. Non-surgical interventions are limited, putatively related to limited insight regarding biochemical events underlying fibrosis, and downstream, the lack of therapeutic targets. YAP/TAZ integrates diverse cell signaling events and interacts with signaling pathways related to fibrosis, including the TGF-β/SMAD pathway. We investigated the expression of YAP/TAZ following vocal fold injury in vivo as well as the effects of TGF-β1 on YAP/TAZ activity in human vocal fold fibroblasts, fibroblast-myofibroblast transition, and TGF-β/SMAD signaling. Iatrogenic injury increased nuclear localization of YAP and TAZ in fibrotic rat vocal folds. In vitro, TGF-β1 activated YAP and TAZ in human VF fibroblasts, and inhibition of YAP/TAZ reversed TGF-β1-stimulated fibroplastic gene upregulation. Additionally, TGF-β1 induced localization of YAP and TAZ in close proximity to SMAD2/3, and nuclear accumulation of SMAD2/3 was inhibited by a YAP/TAZ inhibitor. Collectively, YAP and TAZ were synergistically activated with the TGF-β/SMAD pathway, and likely essential for the fibroplastic phenotypic shift in VF fibroblasts. Based on these data, YAP/TAZ may evolve as an attractive therapeutic target for VF fibrosis.

scholarly journals Use of Gracile and semi-tendinosus tendons (GRAST) for the reconstruction of irreparable rotator cuff tears

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Marie Protais ◽  
Maxime Laurent-Perrot ◽  
Mickaël Artuso ◽  
M. Christian Moody ◽  
Alain Sautet ◽  
...  
Keyword(s):  
Rotator Cuff ◽  
Donor Site ◽  
Anatomical Study ◽  
Donor Site Morbidity ◽  
Rotator Cuff Tears ◽  
Subacromial Space ◽  
Greater Tuberosity ◽  
Working Zone ◽  
Superior Capsular Reconstruction

Abstract Background Irreparable rotator cuff tears are common and difficult to treat. Techniques for “filling the loss of substance” require fixation to the rotator cuff stump (tendon augmentation) or to the glenoid (superior capsular reconstruction), which are complicated by the narrow working zone of the subacromial space. The main objective of this study was to determine whether a braided graft of gracilis (GR) and semitendinosus (ST) could fill a loss of tendon substance from an irreparable rupture of the supra- and infraspinatus, by fixing the graft to the greater tuberosity and the spine of the scapula. Methods This was a cadaveric study with the use of ten specimens. The GRA and ST tendons were harvested, braided and reinforced with suture. An experimental tear of the supraspinatus (SS) and upper infraspinatus (IS) retracted at the glenoid was made. The GRAST transplant was positioned over the tear. The transplant was attached to the greater tuberosity by two anchors and then attached to the medial third of the scapular spine by trans-osseous stitching. The percentage of filling obtained was then measured and passive mobility of the shoulder was assessed. We proceeded to the same technique under arthroscopy for a 73 years old patient whom we treated for a painful shoulder with irreparable cuff tear. We inserted a GRAST graft using arthroscopy. Results The Braided-GRAST allowed a 100% filling of the loss of tendon substance. Mobility was complete in all cases. Conclusion This technique simplifies the medial fixation and restores the musculo-tendinous chain where current grafting techniques only fill a tendinous defect. The transplant could have a subacromial “spacer” effect and lower the humeral head. The donor site morbidity and the fate of the transplant in-vivo are two limits to be discussed. This anatomical study paves the way for clinical experimentation.

scholarly journals Experimental Models of Hepatocellular Carcinoma—A Preclinical Perspective

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3651
Author(s):  
Alexandru Blidisel ◽  
Iasmina Marcovici ◽  
Dorina Coricovac ◽  
Florin Hut ◽  
Cristina Adriana Dehelean ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Molecular Mechanisms ◽  
Prediction Models ◽  
3D Models ◽  
Experimental Models ◽  
Health Concern ◽  
Liver Carcinoma ◽  
Tumor Type

Hepatocellular carcinoma (HCC), the most frequent form of primary liver carcinoma, is a heterogenous and complex tumor type with increased incidence, poor prognosis, and high mortality. The actual therapeutic arsenal is narrow and poorly effective, rendering this disease a global health concern. Although considerable progress has been made in terms of understanding the pathogenesis, molecular mechanisms, genetics, and therapeutical approaches, several facets of human HCC remain undiscovered. A valuable and prompt approach to acquire further knowledge about the unrevealed aspects of HCC and novel therapeutic candidates is represented by the application of experimental models. Experimental models (in vivo and in vitro 2D and 3D models) are considered reliable tools to gather data for clinical usability. This review offers an overview of the currently available preclinical models frequently applied for the study of hepatocellular carcinoma in terms of initiation, development, and progression, as well as for the discovery of efficient treatments, highlighting the advantages and the limitations of each model. Furthermore, we also focus on the role played by computational studies (in silico models and artificial intelligence-based prediction models) as promising novel tools in liver cancer research.

scholarly journals Induced Pluripotent Stem Cells (iPSCs) in Vascular Research: from Two- to Three-Dimensional Organoids

2021 ◽  
Author(s):  
Anja Trillhaase ◽  
Marlon Maertens ◽  
Zouhair Aherrahrou ◽  
Jeanette Erdmann
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Induced Pluripotent Stem Cells ◽  
Stem Cell Research ◽  
Pluripotent Stem Cells ◽  
Embryonic Stem ◽  
Cell Types ◽  
3D Models ◽  
Induced Pluripotent

AbstractStem cell technology has been around for almost 30 years and in that time has grown into an enormous field. The stem cell technique progressed from the first successful isolation of mammalian embryonic stem cells (ESCs) in the 1990s, to the production of human induced-pluripotent stem cells (iPSCs) in the early 2000s, to finally culminate in the differentiation of pluripotent cells into highly specialized cell types, such as neurons, endothelial cells (ECs), cardiomyocytes, fibroblasts, and lung and intestinal cells, in the last decades. In recent times, we have attained a new height in stem cell research whereby we can produce 3D organoids derived from stem cells that more accurately mimic the in vivo environment. This review summarizes the development of stem cell research in the context of vascular research ranging from differentiation techniques of ECs and smooth muscle cells (SMCs) to the generation of vascularized 3D organoids. Furthermore, the different techniques are critically reviewed, and future applications of current 3D models are reported. Graphical abstract

scholarly journals The Role of Biomimetic Hypoxia on Cancer Cell Behaviour in 3D Models: A Systematic Review

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1334
Author(s):  
Ye Liu ◽  
Zahra Mohri ◽  
Wissal Alsheikh ◽  
Umber Cheema
Keyword(s):  
Systematic Review ◽  
Cellular Response ◽  
3D Culture ◽  
3D Models ◽  
In Vitro Models ◽  
Research Findings ◽  
Tissue Models

The development of biomimetic, human tissue models is recognized as being an important step for transitioning in vitro research findings to the native in vivo response. Oftentimes, 2D models lack the necessary complexity to truly recapitulate cellular responses. The introduction of physiological features into 3D models informs us of how each component feature alters specific cellular response. We conducted a systematic review of research papers where the focus was the introduction of key biomimetic features into in vitro models of cancer, including 3D culture and hypoxia. We analysed outcomes from these and compiled our findings into distinct groupings to ascertain which biomimetic parameters correlated with specific responses. We found a number of biomimetic features which primed cancer cells to respond in a manner which matched in vivo response.

BONE STRUCTURE AND STRENGTH ADAPT TO LONG-TERM CYCLIC OVERLOADING IN AN IN VIVO MOUSE MODEL

2012 ◽  
Vol 45 ◽  
pp. S89 ◽  
Author(s):  
Floor M. Lambers ◽  
Kathleen Koch ◽  
Gisela Kuhn ◽  
Claudia Weigt ◽  
Friederike A. Schulte ◽  
...  
Keyword(s):  
Mouse Model ◽  
Bone Structure

Prevascularized, Co-Culture Model for Breast Cancer Drug Development

2012 ◽  
Author(s):  
Lauren Marshall ◽  
Isabel Löwstedt ◽  
Paul Gatenholm ◽  
Joel Berry
Keyword(s):  
Breast Cancer ◽  
Drug Development ◽  
Three Dimensional ◽  
Human Tumor ◽  
3D Models ◽  
Cancer Drug ◽  
Cancer Therapies ◽  
Anti Cancer

The objective of this study was to create 3D engineered tissue models to accelerate identification of safe and efficacious breast cancer drug therapies. It is expected that this platform will dramatically reduce the time and costs associated with development and regulatory approval of anti-cancer therapies, currently a multi-billion dollar endeavor [1]. Existing two-dimensional (2D) in vitro and in vivo animal studies required for identification of effective cancer therapies account for much of the high costs of anti-cancer medications and health insurance premiums borne by patients, many of whom cannot afford it. An emerging paradigm in pharmaceutical drug development is the use of three-dimensional (3D) cell/biomaterial models that will accurately screen novel therapeutic compounds, repurpose existing compounds and terminate ineffective ones. In particular, identification of effective chemotherapies for breast cancer are anticipated to occur more quickly in 3D in vitro models than 2D in vitro environments and in vivo animal models, neither of which accurately mimic natural human tumor environments [2]. Moreover, these 3D models can be multi-cellular and designed with extracellular matrix (ECM) function and mechanical properties similar to that of natural in vivo cancer environments [3].

scholarly journals The Role of Pre-Clinical 3-Dimensional Models of Osteosarcoma

2020 ◽  
Vol 21 (15) ◽  
pp. 5499
Author(s):  
Hannah L. Smith ◽  
Stephen A. Beers ◽  
Juliet C. Gray ◽  
Janos M. Kanczler
Keyword(s):  
Three Dimensional ◽  
Chorioallantoic Membrane ◽  
3D Models ◽  
In Ovo ◽  
Future Directions ◽  
3 Dimensional ◽  
In Vivo Animal Models

Treatment for osteosarcoma (OS) has been largely unchanged for several decades, with typical therapies being a mixture of chemotherapy and surgery. Although therapeutic targets and products against cancer are being continually developed, only a limited number have proved therapeutically active in OS. Thus, the understanding of the OS microenvironment and its interactions are becoming more important in developing new therapies. Three-dimensional (3D) models are important tools in increasing our understanding of complex mechanisms and interactions, such as in OS. In this review, in vivo animal models, in vitro 3D models and in ovo chorioallantoic membrane (CAM) models, are evaluated and discussed as to their contribution in understanding the progressive nature of OS, and cancer research. We aim to provide insight and prospective future directions into the potential translation of 3D models in OS.

Measurement of the velocity of ultrasound in the human femur in vivo

1980 ◽  
Vol 7 (4) ◽  
pp. 324-330 ◽  
Author(s):  
Michael P. André ◽  
J. Duncan Craven ◽  
Moses A. Greenfield ◽  
Richard Stern
Keyword(s):  
Human Femur ◽  
Velocity Of Ultrasound
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