1
|
Kochová P, Malečková A, Pálek R, Liška V, Bońkowski T, Horák M, Grajciarová M, Tonar Z. Porcine spleen as a model organ for blunt injury impact tests: An experimental and histological study. Anat Histol Embryol 2022; 51:576-586. [PMID: 35751561 DOI: 10.1111/ahe.12831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 06/06/2022] [Accepted: 06/06/2022] [Indexed: 11/30/2022]
Abstract
The spleen is a large and highly vascularized secondary lymphatic organ. Spleen injuries are among the most frequent trauma-related injuries in the abdominal region. The aims of the study were to assess the volume fractions of the main splenic tissue components (red pulp, white pulp, trabeculae and reticular fibres) and to determine the severity of splenic injury due to the experimental impact test. Porcine spleens (n = 17) were compressed by 6.22 kg wooden plate using a drop tower technique from three impact heights (50, 100 and 150 mm corresponding to velocities 0.79, 1.24 and 1.58 m/s). The pressure was measured via catheters placed in the splenic vein. The impact velocity was measured using lasers. The severity of induced injuries was analysed on the macroscopic level. The volume fractions of splenic components were assessed microscopically using stereology. The volume fraction of the red pulp was 76.4%, white pulp 21.3% and trabeculae 2.7% respectively. All impact tests, even with the low impact velocities, led to injuries that occurred mostly in the dorsal extremity of the spleen, and were accompanied by bleeding, capsule rupture and parenchyma crushing. Higher impact height (impact velocity and impact energy) caused more severe injury. Porcine spleen had the same volume fraction of tissue components as human spleen, therefore we concluded that the porcine spleen was a suitable organ model for mechanical experiments. Based on our observations, regions around hilum and the diaphragmatic surface of the dorsal extremity, that contained fissures and notches, were the most prone to injury and required considerable attention during splenic examination after injury. The primary mechanical data are now available for the researchers focused on the splenic trauma modelling.
Collapse
Affiliation(s)
- Petra Kochová
- European Centre of Excellence NTIS, Faculty of Applied Sciences, University of West Bohemia, Pilsen, Czech Republic
| | - Anna Malečková
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | - Richard Pálek
- Department of Surgery and Biomedical Center, Faculty of Medicine and University Hospital in Pilsen, Charles University, Pilsen, Czech Republic
| | - Václav Liška
- Department of Surgery and Biomedical Center, Faculty of Medicine and University Hospital in Pilsen, Charles University, Pilsen, Czech Republic
| | - Tomasz Bońkowski
- New Technologies - Research Centre, University of West Bohemia, Pilsen, Czech Republic
| | - Miroslav Horák
- Department of Mechanics, Faculty of Applied Sciences, University of West Bohemia, Pilsen, Czech Republic
| | - Martina Grajciarová
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
| | - Zbyněk Tonar
- European Centre of Excellence NTIS, Faculty of Applied Sciences, University of West Bohemia, Pilsen, Czech Republic
| |
Collapse
|
2
|
Gärtner F, Gihring A, Roth A, Bischof J, Xu P, Elad L, Wabitsch M, Burster T, Knippschild U. Obesity Prolongs the Inflammatory Response in Mice After Severe Trauma and Attenuates the Splenic Response to the Inflammatory Reflex. Front Immunol 2021; 12:745132. [PMID: 34867969 PMCID: PMC8634681 DOI: 10.3389/fimmu.2021.745132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/25/2021] [Indexed: 11/25/2022] Open
Abstract
Thoracic traumas with extra-thoracic injuries result in an immediate, complex host response. The immune response requires tight regulation and can be influenced by additional risk factors such as obesity, which is considered a state of chronic inflammation. Utilizing high-dimensional mass and regular flow cytometry, we define key signatures of obesity-related alterations of the immune system during the response to the trauma. In this context, we report a modification in important components of the splenic response to the inflammatory reflex in obese mice. Furthermore, during the response to trauma, obese mice exhibit a prolonged increase of neutrophils and an early accumulation of inflammation associated CCR2+CD62L+Ly6Chi monocytes in the blood, contributing to a persistent inflammatory phase. Moreover, these mice exhibit differences in migration patterns of monocytes to the traumatized lung, resulting in decreased numbers of regenerative macrophages and an impaired M1/M2 switch in traumatized lungs. The findings presented in this study reveal an attenuation of the inflammatory reflex in obese mice, as well as a disturbance of the monocytic compartment contributing to a prolonged inflammation phase resulting in fewer phenotypically regenerative macrophages in the lung of obese mice.
Collapse
Affiliation(s)
- Fabian Gärtner
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| | - Adrian Gihring
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| | - Aileen Roth
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| | - Joachim Bischof
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| | - Pengfei Xu
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| | - Leonard Elad
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, Ulm University Medical Center, Ulm, Germany
| | - Timo Burster
- Department of Biology, School of Sciences and Humanities, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Uwe Knippschild
- Department of General and Visceral Surgery, Surgery Center, Ulm University Medical Center, Ulm, Germany
| |
Collapse
|
3
|
Non-minimum phase viscoelastic properties of soft biological tissues. J Mech Behav Biomed Mater 2020; 110:103795. [PMID: 32957173 DOI: 10.1016/j.jmbbm.2020.103795] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 03/16/2020] [Accepted: 04/12/2020] [Indexed: 01/05/2023]
Abstract
Understanding the viscoelastic properties of biological tissues is important because they can reveal tissue structure. This study analyzes the viscoelastic properties of soft biological tissues using a fractional dynamics model. We conducted a dynamic viscoelastic test on several porcine samples, i.e., liver, breast, and skeletal muscle tissues, using a plate-plate rheometer. We found that some soft biological tissues have non-minimum phase properties, i.e., the relationship between compliance and phase delay is not uniquely related to the non-integer derivative order in the fractional dynamics model. The experimental results show that the actual phase delay is larger than that estimated from compliance. We propose an empirical model to represent these non-minimum phase properties; a fractional Maxwell model with the fractional Hilbert transform term is proposed. The model and experimental results were highly correlated in terms of compliance and phase diagrams, and complex mechanical impedance. We also show that the amount of additional phase delay, defined as the increase in actual phase delay compared to that estimated from compliance, differs with tissue type.
Collapse
|
4
|
Wang M, Liu S, Xu Z, Qu K, Li M, Chen X, Xue Q, Genin GM, Lu TJ, Xu F. Characterizing poroelasticity of biological tissues by spherical indentation: an improved theory for large relaxation. JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 2020; 138:103920. [PMID: 33132418 PMCID: PMC7595329 DOI: 10.1016/j.jmps.2020.103920] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Flow of fluids within biological tissues often meets with resistance that causes a rate- and size-dependent material behavior known as poroelasticity. Characterizing poroelasticity can provide insight into a broad range of physiological functions, and is done qualitatively in the clinic by palpation. Indentation has been widely used for characterizing poroelasticity of soft materials, where quantitative interpretation of indentation requires a model of the underlying physics, and such existing models are well established for cases of small strain and modest force relaxation. We showed here that existing models are inadequate for large relaxation, where the force on the indenter at a prescribed depth at long-time scale drops to below half of the initially peak force (i.e., F(0)/F(∞) > 2). We developed an indentation theory for such cases of large relaxation, based on Biot theory and a generalized Hertz contact model. We demonstrated that our proposed theory is suitable for biological tissues (e.g., spleen, kidney, skin and human cirrhosis liver) with both small and large relaxations. The proposed method would be a powerful tool to characterize poroelastic properties of biological materials for various applications such as pathological study and disease diagnosis.
Collapse
Affiliation(s)
- Ming Wang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Shaanxi, 710049, P.R. China
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P.R. China
| | - Shaobao Liu
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P.R. China
- Nanjing Center for Multifunctional Lightweight Materials and Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 21006, P.R. China
| | - Zhimin Xu
- State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi’an Jiaotong University, Xi’an 710049, P.R. China
| | - Kai Qu
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, China
| | - Moxiao Li
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
- State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi’an Jiaotong University, Xi’an 710049, P.R. China
| | - Xin Chen
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
- State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi’an Jiaotong University, Xi’an 710049, P.R. China
| | - Qing Xue
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
- State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi’an Jiaotong University, Xi’an 710049, P.R. China
| | - Guy M. Genin
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Shaanxi, 710049, P.R. China
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
- National Science Foundation Science and Technology Center for Engineering Mechanobiology, Washington University, St. Louis, MO 63130, USA
| | - Tian Jian Lu
- State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, P.R. China
- Nanjing Center for Multifunctional Lightweight Materials and Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 21006, P.R. China
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Shaanxi, 710049, P.R. China
- Bioinspired Engineering & Biomechanics Center (BEBC), Xi’an Jiaotong University, Xi’an 710049, P.R. China
| |
Collapse
|
5
|
Mechanical behaviors of tension and relaxation of tongue and soft palate: Experimental and analytical modeling. J Theor Biol 2018; 459:142-153. [PMID: 30287357 DOI: 10.1016/j.jtbi.2018.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 09/27/2018] [Accepted: 10/01/2018] [Indexed: 11/21/2022]
Abstract
This study is to characterize mechanical properties of uniaxial tension and stress relaxation responses of muscle tissues of tongue and soft palate. Uniaxial tension test and stress relaxation test on 39 fresh tissue samples from four five-month-old boars (65 ± 15 kg) are conducted. Firstly, the rationality of the samples' dimension design and experimenal data measurement is validated by one-way ANOVA F-type test. Mechanical properties, including stress-strain relationship and stress relaxation characteristic, are then investigated in details to show the nonlinear behaviors of the tissue samples clearly. Finally, a constitutive model of representing the mechanical properties is formulated within the nonlinear integral representation framework proposed by Pinkin and Rogers, and corresponding material parameters are fitted to the experimental data based on the Levenberg-Marquardt minimization algorithm. The results of the fitting comparison prove that the formulated constitutive model can capture the observed nonlinear behaviors of the muscle tissue samples in both the axial tension and stress relaxation experiments.
Collapse
|
6
|
Fiber orientation effects in simple shearing of fibrous soft tissues. J Biomech 2017; 64:131-135. [DOI: 10.1016/j.jbiomech.2017.09.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/07/2017] [Accepted: 09/19/2017] [Indexed: 11/23/2022]
|
7
|
New regime in the mechanical behavior of skin: strain-softening occurring before strain-hardening. J Mech Behav Biomed Mater 2017; 69:98-106. [DOI: 10.1016/j.jmbbm.2016.12.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/19/2016] [Accepted: 12/23/2016] [Indexed: 11/19/2022]
|
8
|
Umale S, Deck C, Bourdet N, Diana M, Soler L, Willinger R. Experimental and finite element analysis for prediction of kidney injury under blunt impact. J Biomech 2017. [DOI: 10.1016/j.jbiomech.2015.06.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
9
|
Dương MT, Nguyễn NH, Trần TN, Tolba R, Staat M. Influence of refrigerated storage on tensile mechanical properties of porcine liver and spleen. Int Biomech 2015. [DOI: 10.1080/23335432.2015.1049295] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
|
10
|
Edelman M. On the fractional Eulerian numbers and equivalence of maps with long term power-law memory (integral Volterra equations of the second kind) to Grünvald-Letnikov fractional difference (differential) equations. CHAOS (WOODBURY, N.Y.) 2015; 25:073103. [PMID: 26232954 DOI: 10.1063/1.4922834] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper, we consider a simple general form of a deterministic system with power-law memory whose state can be described by one variable and evolution by a generating function. A new value of the system's variable is a total (a convolution) of the generating functions of all previous values of the variable with weights, which are powers of the time passed. In discrete cases, these systems can be described by difference equations in which a fractional difference on the left hand side is equal to a total (also a convolution) of the generating functions of all previous values of the system's variable with the fractional Eulerian number weights on the right hand side. In the continuous limit, the considered systems can be described by the Grünvald-Letnikov fractional differential equations, which are equivalent to the Volterra integral equations of the second kind. New properties of the fractional Eulerian numbers and possible applications of the results are discussed.
Collapse
Affiliation(s)
- Mark Edelman
- Department of Physics, Stern College at Yeshiva University, 245 Lexington Ave., New York, New York 10016, USA; Courant Institute of Mathematical Sciences, New York University, 251 Mercer St., New York, New York 10012, USA; and Department of Mathematics, BCC, CUNY, 2155 University Avenue, Bronx, New York 10453, USA
| |
Collapse
|
11
|
Bège T, Ménard J, Tremblay J, Denis R, Arnoux PJ, Petit Y. Biomechanical analysis of traumatic mesenteric avulsion. Med Biol Eng Comput 2014; 53:187-94. [PMID: 25408251 DOI: 10.1007/s11517-014-1212-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 10/13/2014] [Indexed: 11/30/2022]
Abstract
Mesenteric avulsion, corresponding to a tearing of intestine's root, generally results from high deceleration in road accidents. The biomechanical analysis of bowel and mesenteric injuries is a major challenge for injury prevention, particularly because seat belt restraint may paradoxically increase their risk of occurrence. The aim of this study was to identify the biomechanical behavior of mesentery and small bowel (MSB) tissue samples under dynamical loading conditions. A dedicated test bench was designed in order to perform tensile tests on fresh MSB porcine specimens, with quasi-static (1 mm/s) and dynamic (100 mm/s) loading conditions. The mechanical behavior of MSB specimens was investigated and compared to isolated mesenteric and isolated small bowel specimens. The results show a high sensitivity of MSB stiffness (1.0 ± 0.2 and 1.3 ± 0.3 N/mm at 1 and 100 mm/s, p = 0.001) and ultimate force (22 ± 5 and 35 ± 8 N at 1 and 100 mm/s, p = 0.001) to the loading rate but not for the displacement at failure. This leads to postulate on a failure criteria based on strain level regardless of the strain rate. These experimental results could be further used to develop refined finite element models and to further investigate on injury mechanisms associated to seat belt restraints, as well as to evaluate and improve protective devices.
Collapse
Affiliation(s)
- Thierry Bège
- Laboratoire de Biomécanique Appliquée UMR24, Department of General Surgery, Hôpital Nord, Aix-Marseille University, Chemin des Bourrelly, 13015, Marseille, France,
| | | | | | | | | | | |
Collapse
|
12
|
Identification of the viscoelastic properties of soft materials at low frequency: Performance, ill-conditioning and extrapolation capabilities of fractional and exponential models. J Mech Behav Biomed Mater 2014; 37:286-98. [DOI: 10.1016/j.jmbbm.2014.05.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/28/2014] [Accepted: 05/30/2014] [Indexed: 11/21/2022]
|
13
|
Nicolle S, Noguer L, Palierne JF. Shear mechanical properties of the porcine pancreas: experiment and analytical modelling. J Mech Behav Biomed Mater 2013; 26:90-7. [PMID: 23820244 DOI: 10.1016/j.jmbbm.2013.05.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 05/16/2013] [Accepted: 05/27/2013] [Indexed: 12/31/2022]
Abstract
We provide the first account of the shear mechanical properties of porcine pancreas using a rheometer both in linear oscillatory tests and in constant strain-rate tests reaching the non-linear sub-failure regime. Our results show that pancreas has a low and weakly frequency-dependent dynamic modulus and experiences a noticeable strain-hardening beyond 20% strain. In both linear and non-linear regime, the viscoelastic behaviour of porcine pancreas follows a four-parameter bi-power model that has been validated on kidney, liver and spleen. Among the four solid organs of the abdomen, pancreas proves to be the most compliant and the most viscous one.
Collapse
Affiliation(s)
- S Nicolle
- Université de Lyon, F-69622, Lyon, France.
| | | | | |
Collapse
|
14
|
Umale S, Deck C, Bourdet N, Dhumane P, Soler L, Marescaux J, Willinger R. Experimental mechanical characterization of abdominal organs: liver, kidney & spleen. J Mech Behav Biomed Mater 2012; 17:22-33. [PMID: 23127642 DOI: 10.1016/j.jmbbm.2012.07.010] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 07/10/2012] [Accepted: 07/27/2012] [Indexed: 01/21/2023]
Abstract
Abdominal organs are the most vulnerable body parts during vehicle trauma, leading to high mortality rate due to acute injuries of liver, kidney, spleen and other abdominal organs. Accurate mechanical properties and FE models of these organs are required for simulating the traumas, so that better designing of the accident environment can be done and the organs can be protected from severe damage. Also from biomedical aspect, accurate mechanical properties of organs are required for better designing of surgical tools and virtual surgery environments. In this study porcine liver, kidney and spleen tissues are studied in vitro and hyper-elastic material laws are provided for each. 12 porcine kidneys are used to perform 40 elongation tests on renal capsule and 60 compression tests on renal cortex, 5 porcine livers are used to perform 45 static compression tests on liver parenchyma and 5 porcine spleens are used to carry out 20 compression tests. All the tests are carried out at a static speed of 0.05 mm/s. A comparative analysis of all the results is done with the literature and though the results are of same order of magnitude, a slight dissonance is observed for the renal capsule. It is also observed that the spleen is the least stiff organ in the abdomen whereas the kidney is the stiffest. The results of this study would be essential to develop the FE models of liver, kidney and spleen which can be further used for impact biomechanical and biomedical applications.
Collapse
Affiliation(s)
- Sagar Umale
- Institut de Mécanique des Fluides et des Solides, UNISTRA-CNRS, Strasbourg, France
| | | | | | | | | | | | | |
Collapse
|