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Swackhamer C, Bedane T, Keppler S, Poltorak A, Cheung K, Awais N, Marra F, Bornhorst GM. Development and analysis of a multi-module peristaltic simulator for gastrointestinal research. Food Res Int 2023; 170:112877. [PMID: 37316038 DOI: 10.1016/j.foodres.2023.112877] [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: 12/15/2022] [Revised: 03/06/2023] [Accepted: 04/20/2023] [Indexed: 06/16/2023]
Abstract
Many existing in vitro digestion systems do not accurately represent the peristaltic contractions of the gastrointestinal system; most of the systems that have physiologically-relevant peristaltic contractions have low throughput and can only test one sample at a time. A device has been developed that provides simulated peristaltic contractions for up to 12 digestion modules simultaneously using rollers of varying width to modulate the dynamics of the peristaltic motion. The force applied to a simulated food bolus varied from 2.61 ± 0.03 N to 4.51 ± 0.16 N (p < 0.05) depending on roller width. Video analysis showed that the degree of occlusion of the digestion module varied from 72.1 ± 0.4% to 84.6 ± 1.2% (p < 0.05). A multiphysics, computational fluid dynamics model was created to understand the fluid flow. The fluid flow was also examined experimentally using video analysis of tracer particles. The model-predicted maximum fluid velocity in the peristaltic simulator incorporating the thin rollers was 0.016 m/s, and the corresponding value measured using tracer particles was 0.015 m/s. The occlusion, pressure, and fluid velocity in the new peristaltic simulator fell within physiologically representative ranges. Although no in vitro device perfectly recreates the conditions of the gastrointestinal system, this novel device is a flexible platform for future gastrointestinal research and could allow for high-throughput screening of food materials for health-promoting properties under conditions representative of human gastrointestinal motility.
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Affiliation(s)
- Clay Swackhamer
- Department of Biological and Agricultural Engineering, University of California, Davis, USA
| | - Tesfaye Bedane
- UCD School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - Silvia Keppler
- Department of Biological and Agricultural Engineering, University of California, Davis, USA
| | - Adam Poltorak
- Department of Biological and Agricultural Engineering, University of California, Davis, USA
| | - Kyle Cheung
- Department of Biological and Agricultural Engineering, University of California, Davis, USA
| | - Nashea Awais
- Department of Biological and Agricultural Engineering, University of California, Davis, USA
| | - Francesco Marra
- Dipartimento di Ingegneria Industriale, Università degli Studi di Salerno, 84084 Fisciano, Italy
| | - Gail M Bornhorst
- Department of Biological and Agricultural Engineering, University of California, Davis, USA; Riddet Institute, Palmerston North, New Zealand.
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2
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Computational Simulation of Colorectal Cancer Biomarker Particle Mobility in a 3D Model. Molecules 2023; 28:molecules28020589. [PMID: 36677649 PMCID: PMC9865637 DOI: 10.3390/molecules28020589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 01/11/2023] Open
Abstract
Even though some methods for the detection of colorectal cancer have been used clinically, most of the techniques used do not consider the in situ detection of colorectal cancer (CRC) biomarkers, which would favor in vivo real-time monitoring of the carcinogenesis process and consequent studies of the disease. In order to give a scientific and computational framework ideal for the evaluation of diagnosis techniques based on the early detection of biomarker molecules modeled as spherical particles from the computational point of view, a computational representation of the rectum, stool and biomarker particles was developed. As consequence of the transport of stool, there was a displacement of CRC biomarker particles that entered the system as a result of the cellular apoptosis processes in polyps with a length lower than 1 cm, reaching a maximum velocity of 3.47×10-3 m/s. The biomarkers studied showed trajectories distant to regions of the polyp of origin in 1 min of simulation. The research results show that the biomarker particles for CRC respond to the variations in the movements of the stool with trajectories and speeds that depend on the location of the injury, which will allow locating the regions with the highest possibilities of catching particles through in situ measurement instruments in the future.
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3
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Schütt M, O’Farrell C, Stamatopoulos K, Hoad CL, Marciani L, Sulaiman S, Simmons MJH, Batchelor HK, Alexiadis A. Simulating the Hydrodynamic Conditions of the Human Ascending Colon: A Digital Twin of the Dynamic Colon Model. Pharmaceutics 2022; 14:pharmaceutics14010184. [PMID: 35057077 PMCID: PMC8778200 DOI: 10.3390/pharmaceutics14010184] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/26/2021] [Accepted: 01/11/2022] [Indexed: 12/21/2022] Open
Abstract
The performance of solid oral dosage forms targeting the colon is typically evaluated using standardised pharmacopeial dissolution apparatuses. However, these fail to replicate colonic hydrodynamics. This study develops a digital twin of the Dynamic Colon Model; a physiologically representative in vitro model of the human proximal colon. Magnetic resonance imaging of the Dynamic Colon Model verified that the digital twin robustly replicated flow patterns under different physiological conditions (media viscosity, volume, and peristaltic wave speed). During local contractile activity, antegrade flows of 0.06-0.78 cm s-1 and backflows of -2.16--0.21 cm s-1 were measured. Mean wall shear rates were strongly time and viscosity dependent although peaks were measured between 3.05-10.12 s-1 and 5.11-20.34 s-1 in the Dynamic Colon Model and its digital twin respectively, comparable to previous estimates of the USPII with paddle speeds of 25 and 50 rpm. It is recommended that viscosity and shear rates are considered when designing future dissolution test methodologies for colon-targeted formulations. In the USPII, paddle speeds >50 rpm may not recreate physiologically relevant shear rates. These findings demonstrate how the combination of biorelevant in vitro and in silico models can provide new insights for dissolution testing beyond established pharmacopeial methods.
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Affiliation(s)
- Michael Schütt
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (K.S.); (M.J.H.S.)
- Correspondence: (M.S.); (C.O.); (A.A.)
| | - Connor O’Farrell
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (K.S.); (M.J.H.S.)
- Correspondence: (M.S.); (C.O.); (A.A.)
| | - Konstantinos Stamatopoulos
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (K.S.); (M.J.H.S.)
- Biopharmaceutics, Pharmaceutical Development, PDS, MST, RD Platform Technology & Science, GSK, David Jack Centre, Park Road, Ware, Hertfordshire SG12 0DP, UK
| | - Caroline L. Hoad
- Nottingham Digestive Diseases Centre and National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham NG7 2UK, UK; (C.L.H.); (L.M.); (S.S.)
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK
| | - Luca Marciani
- Nottingham Digestive Diseases Centre and National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham NG7 2UK, UK; (C.L.H.); (L.M.); (S.S.)
| | - Sarah Sulaiman
- Nottingham Digestive Diseases Centre and National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham NG7 2UK, UK; (C.L.H.); (L.M.); (S.S.)
| | - Mark J. H. Simmons
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (K.S.); (M.J.H.S.)
| | - Hannah K. Batchelor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK;
| | - Alessio Alexiadis
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (K.S.); (M.J.H.S.)
- Correspondence: (M.S.); (C.O.); (A.A.)
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4
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Costa M, Wiklendt L, Hibberd T, Dinning P, Spencer NJ, Brookes S. Analysis of Intestinal Movements with Spatiotemporal Maps: Beyond Anatomy and Physiology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1383:271-294. [PMID: 36587166 DOI: 10.1007/978-3-031-05843-1_26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Over 150 years ago, methods for quantitative analysis of gastrointestinal motor patterns first appeared. Graphic representations of physiological variables were recorded with the kymograph after the mid-1800s. Changes in force or length of intestinal muscles could be quantified, however most recordings were limited to a single point along the digestive tract.In parallel, photography and cinematography with X-Rays visualised changes in intestinal shape, but were hard to quantify. More recently, the ability to record physiological events at many sites along the gut in combination with computer processing allowed construction of spatiotemporal maps. These included diameter maps (DMaps), constructed from video recordings of intestinal movements and pressure maps (PMaps), constructed using data from high-resolution manometry catheters. Combining different kinds of spatiotemporal maps revealed additional details about gut wall status, including compliance, which relates forces to changes in length. Plotting compliance values along the intestine enabled combined DPMaps to be constructed, which can distinguish active contractions and relaxations from passive changes. From combinations of spatiotemporal maps, it is possible to deduce the role of enteric circuits and pacemaker cells in the generation of complex motor patterns. Development and application of spatiotemporal methods to normal and abnormal motor patterns in animals and humans is ongoing, with further technical improvements arising from their combination with impedance manometry, magnetic resonance imaging, electrophysiology, and ultrasonography.
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Affiliation(s)
- Marcello Costa
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia.
| | - Luke Wiklendt
- Department of Gastroenterology and Surgery, Flinders Medical Centre, Bedford Park, SA, Australia
| | - Tim Hibberd
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia
| | - Phil Dinning
- Department of Gastroenterology and Surgery, Flinders Medical Centre, Bedford Park, SA, Australia
| | - Nick J Spencer
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia
| | - Simon Brookes
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia
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5
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Yang SY, Sencadas V, You SS, Jia NZX, Srinivasan SS, Huang HW, Ahmed AE, Liang JY, Traverso G. Powering Implantable and Ingestible Electronics. ADVANCED FUNCTIONAL MATERIALS 2021; 31:2009289. [PMID: 34720792 PMCID: PMC8553224 DOI: 10.1002/adfm.202009289] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Indexed: 05/28/2023]
Abstract
Implantable and ingestible biomedical electronic devices can be useful tools for detecting physiological and pathophysiological signals, and providing treatments that cannot be done externally. However, one major challenge in the development of these devices is the limited lifetime of their power sources. The state-of-the-art of powering technologies for implantable and ingestible electronics is reviewed here. The structure and power requirements of implantable and ingestible biomedical electronics are described to guide the development of powering technologies. These powering technologies include novel batteries that can be used as both power sources and for energy storage, devices that can harvest energy from the human body, and devices that can receive and operate with energy transferred from exogenous sources. Furthermore, potential sources of mechanical, chemical, and electromagnetic energy present around common target locations of implantable and ingestible electronics are thoroughly analyzed; energy harvesting and transfer methods befitting each energy source are also discussed. Developing power sources that are safe, compact, and have high volumetric energy densities is essential for realizing long-term in-body biomedical electronics and for enabling a new era of personalized healthcare.
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Affiliation(s)
- So-Yoon Yang
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Vitor Sencadas
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; School of Mechanical, Materials & Mechatronics Engineering, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Siheng Sean You
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Neil Zi-Xun Jia
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Shriya Sruthi Srinivasan
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Hen-Wei Huang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Abdelsalam Elrefaey Ahmed
- Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jia Ying Liang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Giovanni Traverso
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Gastroenterology, Hepatology and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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6
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Bhatti MM, Zeeshan A, Bashir F, Sait SM, Ellahi R. Sinusoidal motion of small particles through a Darcy-Brinkman-Forchheimer microchannel filled with non-Newtonian fluid under electro-osmotic forces. JOURNAL OF TAIBAH UNIVERSITY FOR SCIENCE 2021. [DOI: 10.1080/16583655.2021.1991734] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- M. M. Bhatti
- College of Mathematics and Systems Science, Shandong University of Science and Technology, Qingdao, People’s Republic of China
| | - A. Zeeshan
- Department of Mathematics, International Islamic University, Islamabad, Pakistan
| | - F. Bashir
- Department of Mathematics, International Islamic University, Islamabad, Pakistan
| | - Sadiq M. Sait
- Center for Communications and IT Research, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia
| | - Rahamat Ellahi
- Department of Mathematics, International Islamic University, Islamabad, Pakistan
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7
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Luminal Fluid Motion Inside an In Vitro Dissolution Model of the Human Ascending Colon Assessed Using Magnetic Resonance Imaging. Pharmaceutics 2021; 13:pharmaceutics13101545. [PMID: 34683837 PMCID: PMC8538555 DOI: 10.3390/pharmaceutics13101545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/14/2021] [Accepted: 09/16/2021] [Indexed: 12/24/2022] Open
Abstract
Knowledge of luminal flow inside the human colon remains elusive, despite its importance for the design of new colon-targeted drug delivery systems and physiologically relevant in silico models of dissolution mechanics within the colon. This study uses magnetic resonance imaging (MRI) techniques to visualise, measure and differentiate between different motility patterns within an anatomically representative in vitro dissolution model of the human ascending colon: the dynamic colon model (DCM). The segmented architecture and peristalsis-like contractile activity of the DCM generated flow profiles that were distinct from compendial dissolution apparatuses. MRI enabled different motility patterns to be classified by the degree of mixing-related motion using a new tagging method. Different media viscosities could also be differentiated, which is important for an understanding of colonic pathophysiology, the conditions that a colon-targeted dosage form may be subjected to and the effectiveness of treatments. The tagged MRI data showed that the DCM effectively mimicked wall motion, luminal flow patterns and the velocities of the contents of the human ascending colon. Accurate reproduction of in vivo hydrodynamics is an essential capability for a biorelevant mechanical model of the colon to make it suitable for in vitro data generation for in vitro in vivo evaluation (IVIVE) or in vitro in vivo correlation (IVIVC). This work illustrates how the DCM provides new insight into how motion of the colonic walls may control luminal hydrodynamics, driving erosion of a dosage form and subsequent drug release, compared to traditional pharmacopeial methods.
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8
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Bhattarai A, Kowalczyk W, Tran TN. A literature review on large intestinal hyperelastic constitutive modeling. Clin Biomech (Bristol, Avon) 2021; 88:105445. [PMID: 34416632 DOI: 10.1016/j.clinbiomech.2021.105445] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 06/29/2021] [Accepted: 07/29/2021] [Indexed: 02/07/2023]
Abstract
Impacts, traumas and strokes are spontaneously life-threatening, but chronic symptoms strangle patient every day. Colorectal tissue mechanics in such chronic situations not only regulates the physio-psychological well-being of the patient, but also confirms the level of comfort and post-operative clinical outcomes. Numerous uniaxial and multiaxial tensile experiments on healthy and affected samples have evidenced significant differences in tissue mechanical behavior and strong colorectal anisotropy across each layer in thickness direction and along the length. Furthermore, this study reviewed various forms of passive constitutive models for the highly fibrous colorectal tissue ranging from the simplest linearly elastic and the conventional isotropic hyperelastic to the most sophisticated second harmonic generation image based anisotropic mathematical formulation. Under large deformation, the isotropic description of tissue mechanics is unequivocally ineffective which demands a microstructural based tissue definition. Therefore, the information collected in this review paper would present the current state-of-the-art in colorectal biomechanics and profoundly serve as updated computational resources to develop a sophisticated characterization of colorectal tissues.
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Affiliation(s)
- Aroj Bhattarai
- Department of Orthopaedic Surgery, University of Saarland, Germany
| | | | - Thanh Ngoc Tran
- Department of Orthopaedic Surgery, University of Saarland, Germany.
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9
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Alexiadis A, Simmons MJH, Stamatopoulos K, Batchelor HK, Moulitsas I. The virtual physiological human gets nerves! How to account for the action of the nervous system in multiphysics simulations of human organs. J R Soc Interface 2021; 18:20201024. [PMID: 33849336 PMCID: PMC8086920 DOI: 10.1098/rsif.2020.1024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
This article shows how to couple multiphysics and artificial neural networks to design computer models of human organs that autonomously adapt their behaviour to environmental stimuli. The model simulates motility in the intestine and adjusts its contraction patterns to the physical properties of the luminal content. Multiphysics reproduces the solid mechanics of the intestinal membrane and the fluid mechanics of the luminal content; the artificial neural network replicates the activity of the enteric nervous system. Previous studies recommended training the network with reinforcement learning. Here, we show that reinforcement learning alone is not enough; the input–output structure of the network should also mimic the basic circuit of the enteric nervous system. Simulations are validated against in vivo measurements of high-amplitude propagating contractions in the human intestine. When the network has the same input–output structure of the nervous system, the model performs well even when faced with conditions outside its training range. The model is trained to optimize transport, but it also keeps stress in the membrane low, which is exactly what occurs in the real intestine. Moreover, the model responds to atypical variations of its functioning with ‘symptoms’ that reflect those arising in diseases. If the healthy intestine model is made artificially ill by adding digital inflammation, motility patterns are disrupted in a way consistent with inflammatory pathologies such as inflammatory bowel disease.
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Affiliation(s)
- A Alexiadis
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston B15 2TT, UK
| | - M J H Simmons
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston B15 2TT, UK
| | - K Stamatopoulos
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston B15 2TT, UK.,Biopharmaceutics, Pharmaceutical Development, PDS, MST, RD Platform Technology and Science, GSK, David Jack Centre, Park Road, Ware, Hertfordshire SG12 0DP, UK
| | - H K Batchelor
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow G4 0RE, UK
| | - I Moulitsas
- Centre for Computational Engineering Sciences, Cranfield University, Bedford MK43 0AL, UK
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10
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Abstract
In this paper, effects of stationary contraction on mixing and transport of a non-Newtonian fluid in the small intestine are analyzed theoretically. A semi-analytical method is developed to solve the governing equations of fluids flow in the intestine using lubrication theory. Results indicate that the stationary contraction helps in conferring two functions – (1) shearing of the contents, and (2) bidirectional transport over a short distance. The flow resulting from contraction is symmetric and occurs in both the directions; however, they do not lead to a net flow rate in one direction. The amount of shearing developed during such flows is reflective of their mixing ability. The effort of such peristalsis is largely determined by the flow behavior index; where energy requirements of developing similar shearing forces are higher for dilatants and lower for pseudoplastics. Flow is sensitive to frequency of contraction, luminal occlusion and wavelength of the contraction.
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Affiliation(s)
- RAVI KANT AVVARI
- Department of Biotechnology and Medical Engineering, NIT Rourkela, Odisha 769008, India
- Department of Electrical & Electronics Engineering, Sasi Institute of Technology and Engineering, Tadepalligudem, West Godavari, Andhra Pradesh 534101, India
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11
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The role of circular folds in mixing intensification in the small intestine: A numerical study. Chem Eng Sci 2021. [DOI: 10.1016/j.ces.2020.116079] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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12
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Dariel A, Grynberg L, Auger M, Lefèvre C, Durand T, Aubert P, Le Berre-Scoul C, Venara A, Suply E, Leclair MD, de Vries P, Levard G, Parmentier B, Podevin G, Schmitt F, Couvrat V, Irtan S, Hervieux E, Villemagne T, Lardy H, Capito C, Muller C, Sarnacki S, Mosnier JF, Galmiche L, Derkinderen P, Boudin H, Brochard C, Neunlist M. Analysis of enteric nervous system and intestinal epithelial barrier to predict complications in Hirschsprung's disease. Sci Rep 2020; 10:21725. [PMID: 33303794 PMCID: PMC7729910 DOI: 10.1038/s41598-020-78340-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 11/18/2020] [Indexed: 12/12/2022] Open
Abstract
In Hirschsprung’s disease (HSCR), postoperative course remains unpredictable. Our aim was to define predictive factors of the main postoperative complications: obstructive symptoms (OS) and Hirschsprung-associated enterocolitis (HAEC). In this prospective multicentre cohort study, samples of resected bowel were collected at time of surgery in 18 neonates with short-segment HSCR in tertiary care hospitals. OS and HAEC were noted during postoperative follow-up. We assessed the enteric nervous system and the intestinal epithelial barrier (IEB) in ganglionic segments by combining immunohistochemical, proteomic and transcriptomic approaches, with functional ex vivo analysis of motility and para/transcellular permeability. Ten HSCR patients presented postoperative complications (median follow-up 23.5 months): 6 OS, 4 HAEC (2 with OS), 2 diarrhoea (without OS/HAEC). Immunohistochemical analysis showed a significant 41% and 60% decrease in median number of nNOS-IR myenteric neurons per ganglion in HSCR with OS as compared to HSCR with HAEC/diarrhoea (without OS) and HSCR without complications (p = 0.0095; p = 0.002, respectively). Paracellular and transcellular permeability was significantly increased in HSCR with HAEC as compared to HSCR with OS/diarrhoea without HAEC (p = 0.016; p = 0.009) and HSCR without complications (p = 0.029; p = 0.017). This pilot study supports the hypothesis that modulating neuronal phenotype and enhancing IEB permeability may treat or prevent postoperative complications in HSCR.
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Affiliation(s)
- Anne Dariel
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France. .,Paediatric Surgery Department, La Timone-Enfants Hospital, Assistance Publique des Hôpitaux de Marseille, 264 rue Saint Pierre, 13385, Marseille, France. .,Paediatric Surgery Department, University Hospital of Nantes, Nantes, France.
| | - Lucie Grynberg
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Marie Auger
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Chloé Lefèvre
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Tony Durand
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Philippe Aubert
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Catherine Le Berre-Scoul
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Aurélien Venara
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Etienne Suply
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Marc-David Leclair
- Paediatric Surgery Department, University Hospital of Nantes, Nantes, France
| | - Philine de Vries
- Paediatric Surgery Department, University Hospital of Brest, Brest, France
| | - Guillaume Levard
- Paediatric Surgery Department, University Hospital of Poitiers, Poitiers, France
| | - Benoit Parmentier
- Paediatric Surgery Department, University Hospital of Poitiers, Poitiers, France
| | - Guillaume Podevin
- Paediatric Surgery Department, University Hospital of Angers, Angers, France
| | - Françoise Schmitt
- Paediatric Surgery Department, University Hospital of Angers, Angers, France
| | | | - Sabine Irtan
- Paediatric Surgery Department, Armand Trousseau Hospital, Paris, France
| | - Erik Hervieux
- Paediatric Surgery Department, Armand Trousseau Hospital, Paris, France
| | - Thierry Villemagne
- Paediatric Surgery Department, University Hospital of Tours, Tours, France
| | - Hubert Lardy
- Paediatric Surgery Department, University Hospital of Tours, Tours, France
| | - Carmen Capito
- Paediatric Surgery Department, Necker Enfants Malades Hospital, Paris, France
| | - Cécile Muller
- Paediatric Surgery Department, Necker Enfants Malades Hospital, Paris, France
| | - Sabine Sarnacki
- Paediatric Surgery Department, Necker Enfants Malades Hospital, Paris, France
| | | | - Louise Galmiche
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France.,Pathology Department, Necker Enfants Malades Hospital, Paris, France
| | - Pascal Derkinderen
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Hélène Boudin
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Charlène Brochard
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
| | - Michel Neunlist
- University of Nantes, INSERM, TENS, The Enteric Nervous System in Gut and Brain Diseases, IMAD, Nantes, France
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Dynamic Colon Model (DCM): A Cine-MRI Informed Biorelevant In Vitro Model of the Human Proximal Large Intestine Characterized by Positron Imaging Techniques. Pharmaceutics 2020; 12:pharmaceutics12070659. [PMID: 32668624 PMCID: PMC7407282 DOI: 10.3390/pharmaceutics12070659] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 12/17/2022] Open
Abstract
This work used in vivo MRI images of human colon wall motion to inform a biorelevant Dynamic Colon Model (DCM) to understand the interplay of wall motion, volume, viscosity, fluid, and particle motion within the colon lumen. Hydrodynamics and particle motion within the DCM were characterized using Positron Emission Tomography (PET) and Positron Emission Particle Tracking (PEPT), respectively. In vitro PET images showed that fluid of higher viscosity follows the wall motion with poor mixing, whereas good mixing was observed for a low viscosity fluid. PEPT data showed particle displacements comparable to the in vivo data. Increasing fluid viscosity favors the net forward propulsion of the tracked particles. The use of a floating particle demonstrated shorter residence times and greater velocities on the liquid surface, suggesting a surface wave that was moving faster than the bulk liquid. The DCM can provide an understanding of flow motion and behavior of particles with different buoyancy, which in turn may improve the design of drug formulations, whereby fragments of the dosage form and/or drug particles are suspended in the proximal colon.
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Shin YC, Shin W, Koh D, Wu A, Ambrosini YM, Min S, Eckhardt SG, Fleming RYD, Kim S, Park S, Koh H, Yoo TK, Kim HJ. Three-Dimensional Regeneration of Patient-Derived Intestinal Organoid Epithelium in a Physiodynamic Mucosal Interface-on-a-Chip. MICROMACHINES 2020; 11:E663. [PMID: 32645991 PMCID: PMC7408321 DOI: 10.3390/mi11070663] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 07/03/2020] [Accepted: 07/05/2020] [Indexed: 12/29/2022]
Abstract
The regeneration of the mucosal interface of the human intestine is critical in the host-gut microbiome crosstalk associated with gastrointestinal diseases. The biopsy-derived intestinal organoids provide genetic information of patients with physiological cytodifferentiation. However, the enclosed lumen and static culture condition substantially limit the utility of patient-derived organoids for microbiome-associated disease modeling. Here, we report a patient-specific three-dimensional (3D) physiodynamic mucosal interface-on-a-chip (PMI Chip) that provides a microphysiological intestinal milieu under defined biomechanics. The real-time imaging and computational simulation of the PMI Chip verified the recapitulation of non-linear luminal and microvascular flow that simulates the hydrodynamics in a living human gut. The multiaxial deformations in a convoluted microchannel not only induced dynamic cell strains but also enhanced particle mixing in the lumen microchannel. Under this physiodynamic condition, an organoid-derived epithelium obtained from the patients diagnosed with Crohn's disease, ulcerative colitis, or colorectal cancer independently formed 3D epithelial layers with disease-specific differentiations. Moreover, co-culture with the human fecal microbiome in an anoxic-oxic interface resulted in the formation of stochastic microcolonies without a loss of epithelial barrier function. We envision that the patient-specific PMI Chip that conveys genetic, epigenetic, and environmental factors of individual patients will potentially demonstrate the pathophysiological dynamics and complex host-microbiome crosstalk to target a patient-specific disease modeling.
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Affiliation(s)
- Yong Cheol Shin
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Woojung Shin
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Domin Koh
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Alexander Wu
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Yoko M. Ambrosini
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Soyoun Min
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - S. Gail Eckhardt
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; (S.G.E.); (R.Y.D.F.)
| | - R. Y. Declan Fleming
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; (S.G.E.); (R.Y.D.F.)
- Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - Seung Kim
- Severance Fecal Microbiota Transplantation Center, Severance Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul 03722, Korea; (S.K.); (S.P.); (H.K.)
| | - Sowon Park
- Severance Fecal Microbiota Transplantation Center, Severance Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul 03722, Korea; (S.K.); (S.P.); (H.K.)
| | - Hong Koh
- Severance Fecal Microbiota Transplantation Center, Severance Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul 03722, Korea; (S.K.); (S.P.); (H.K.)
| | - Tae Kyung Yoo
- Department of Computer Art, College of Art and Technology, Chung-Ang University, Seoul 06974, Korea;
| | - Hyun Jung Kim
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; (S.G.E.); (R.Y.D.F.)
- Department of Medical Engineering, College of Medicine, Yonsei University, Seoul 03722, Korea
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15
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Schütt M, Stamatopoulos K, Simmons MJH, Batchelor HK, Alexiadis A. Modelling and simulation of the hydrodynamics and mixing profiles in the human proximal colon using Discrete Multiphysics. Comput Biol Med 2020; 121:103819. [PMID: 32568686 DOI: 10.1016/j.compbiomed.2020.103819] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 05/10/2020] [Indexed: 12/20/2022]
Abstract
The proximal part of the colon offers opportunities to prolong the absorption window following oral administration of a drug. In this work, we used computer simulations to understand how the hydrodynamics in the proximal colon might affect the release from dosage forms designed to target the colon. For this purpose, we developed and compared three different models: a completely-filled colon, a partially-filled colon and a partially-filled colon with a gaseous phase present (gas-liquid model). The highest velocities of the liquid were found in the completely-filled model, which also shows the best mixing profile, defined by the distribution of tracking particles over time. No significant differences with regard to the mixing and velocity profiles were found between the partially-filled model and the gas-liquid model. The fastest transit time of an undissolved tablet was found in the completely-filled model. The velocities of the liquid in the gas-liquid model are slightly higher along the colon than in the partially-filled model. The filling level has an impact on the exsisting shear forces and shear rates, which are decisive factors in the development of new drugs and formulations.
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Affiliation(s)
- M Schütt
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
| | - K Stamatopoulos
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - M J H Simmons
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - H K Batchelor
- College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT United Kingdom
| | - A Alexiadis
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
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16
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Alexiadis A. Deep multiphysics: Coupling discrete multiphysics with machine learning to attain self-learning in-silico models replicating human physiology. Artif Intell Med 2019; 98:27-34. [PMID: 31521250 DOI: 10.1016/j.artmed.2019.06.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 05/30/2019] [Accepted: 06/24/2019] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The objective of this study is to devise a modelling strategy for attaining in-silico models replicating human physiology and, in particular, the activity of the autonomic nervous system. METHOD Discrete Multiphysics (a multiphysics modelling technique) and Reinforcement Learning (a Machine Learning algorithm) are combined to achieve an in-silico model with the ability of self-learning and replicating feedback loops occurring in human physiology. Computational particles, used in Discrete Multiphysics to model biological systems, are associated to (computational) neurons: Reinforcement Learning trains these neurons to behave like they would in real biological systems. RESULTS As benchmark/validation, we use the case of peristalsis in the oesophagus. Results show that the in-silico model effectively learns by itself how to propel the bolus in the oesophagus. CONCLUSIONS The combination of first principles modelling (e.g. multiphysics) and machine learning (e.g. Reinforcement Learning) represents a new powerful tool for in-silico modelling of human physiology. Biological feedback loops occurring, for instance, in peristaltic or metachronal motion, which until now could not be accounted for in in-silico models, can be tackled by the proposed technique.
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Affiliation(s)
- Alessio Alexiadis
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.
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17
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Bassotti G, Usai Satta P, Bellini M. Prucalopride for the treatment of constipation: a view from 2015 and beyond. Expert Rev Gastroenterol Hepatol 2019; 13:257-262. [PMID: 30791758 DOI: 10.1080/17474124.2019.1568238] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Prucalopride is a prokinetic drug, that has been commercially available in recent years for the treatment of chronically constipated patients. In this update of a previous 2016 article, we reviewed the more recent data supporting its role in the treatment of constipation and constipation-associated conditions. Areas covered: We carried out an extensive literature review on the effects of prucalopride for the years 2012-2018 by means of scientific databases and manual research. More evidence was found on its possible therapeutic role in conditions in which constipation plays a role as an associated symptom, such as opioid-induced constipation, constipation-predominant irritable bowel syndrome, post-operative ileus, colonic diverticular disease, drug-related constipation, and chronic intestinal pseudo-obstruction. Expert opinion: Based on the added literature evidence, we feel that prucalopride is an effective, although expensive, drug for the treatment of primary and secondary forms of constipation, and of other clinical conditions associated with constipation.
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Affiliation(s)
- Gabrio Bassotti
- a Gastroenterology & Hepatology Section, Department of Medicine , University of Perugia Medical School , Perugia , Italy
| | - Paolo Usai Satta
- b Gastrointestinal Unit , "G. Brotzu" Hospital , Cagliari , Italy
| | - Massimo Bellini
- c Gastrointestinal Unit, Department of Translational Research and New Technologies in Medicine and Surgery , University of Pisa , Pisa , Italy
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18
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19
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Harrison SM, Cleary PW, Sinnott MD. Investigating mixing and emptying for aqueous liquid content from the stomach using a coupled biomechanical-SPH model. Food Funct 2018; 9:3202-3219. [DOI: 10.1039/c7fo01226h] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Computational modelling of gastric emptying reveals the complex flow patterns that occur. The resulting mixing is substantial in the inferior stomach but much lower near the fluid's top surface.
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Affiliation(s)
| | - Paul W. Cleary
- CSIRO Data61 and Food and Agriculture
- Clayton South
- Australia 3169
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20
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Ariane M, Allouche MH, Bussone M, Giacosa F, Bernard F, Barigou M, Alexiadis A. Discrete multi-physics: A mesh-free model of blood flow in flexible biological valve including solid aggregate formation. PLoS One 2017; 12:e0174795. [PMID: 28384341 PMCID: PMC5383103 DOI: 10.1371/journal.pone.0174795] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 03/15/2017] [Indexed: 11/23/2022] Open
Abstract
We propose a mesh-free and discrete (particle-based) multi-physics approach for modelling the hydrodynamics in flexible biological valves. In the first part of this study, the method is successfully validated against both traditional modelling techniques and experimental data. In the second part, it is further developed to account for the formation of solid aggregates in the flow and at the membrane surface. Simulations of various types of aggregates highlight the main benefits of discrete multi-physics and indicate the potential of this approach for coupling the hydrodynamics with phenomena such as clotting and calcification in biological valves.
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Affiliation(s)
- Mostapha Ariane
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
- * E-mail: (MA); (AA)
| | | | | | | | - Frédéric Bernard
- Laboratoire Interdisciplinaire Carnot de Bourgogne, Université de Bourgogne Franche-Comté, Dijon, France
| | - Mostafa Barigou
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Alessio Alexiadis
- School of Chemical Engineering, University of Birmingham, Birmingham, United Kingdom
- * E-mail: (MA); (AA)
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21
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Alexiadis A, Stamatopoulos K, Wen W, Batchelor HK, Bakalis S, Barigou M, Simmons MJH. Using discrete multi-physics for detailed exploration of hydrodynamics in an in vitro colon system. Comput Biol Med 2017; 81:188-198. [PMID: 28088672 DOI: 10.1016/j.compbiomed.2017.01.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 12/13/2016] [Accepted: 01/07/2017] [Indexed: 11/15/2022]
Abstract
We developed a mathematical model that describes the motion of viscous fluids in the partially-filled colon caused by the periodic contractions of flexible walls (peristalsis). In-vitro data are used to validate the model. The model is then used to identify two fundamental mechanisms of mass transport: the surfing mode and the pouring mode. The first mechanism is faster, but only involves the surface of the liquid. The second mechanism causes deeper mixing, and appears to be the main transport mechanism. Based on the gained understanding, we propose a series of measures that can improve the reliability of in-vitro models. The tracer in PET-like experiments, in particular, should not be injected in the first pocket, and its viscosity should be as close as possible to that of the fluid. If these conditions are not met, the dynamics of the tracer and the fluid diverge, compromising the accuracy of the in-vitro data.
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Affiliation(s)
- A Alexiadis
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
| | - K Stamatopoulos
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - W Wen
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - H K Batchelor
- College of Medical and Dental Sciences, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - S Bakalis
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - M Barigou
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - M J H Simmons
- School of Chemical Engineering, University of Birmingham, Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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22
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Stamatopoulos K, Batchelor HK, Simmons MJ. Dissolution profile of theophylline modified release tablets, using a biorelevant Dynamic Colon Model (DCM). Eur J Pharm Biopharm 2016; 108:9-17. [DOI: 10.1016/j.ejpb.2016.08.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 07/13/2016] [Accepted: 08/08/2016] [Indexed: 01/06/2023]
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23
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Sjögren E, Thörn H, Tannergren C. In Silico Modeling of Gastrointestinal Drug Absorption: Predictive Performance of Three Physiologically Based Absorption Models. Mol Pharm 2016; 13:1763-78. [PMID: 26926043 DOI: 10.1021/acs.molpharmaceut.5b00861] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Gastrointestinal (GI) drug absorption is a complex process determined by formulation, physicochemical and biopharmaceutical factors, and GI physiology. Physiologically based in silico absorption models have emerged as a widely used and promising supplement to traditional in vitro assays and preclinical in vivo studies. However, there remains a lack of comparative studies between different models. The aim of this study was to explore the strengths and limitations of the in silico absorption models Simcyp 13.1, GastroPlus 8.0, and GI-Sim 4.1, with respect to their performance in predicting human intestinal drug absorption. This was achieved by adopting an a priori modeling approach and using well-defined input data for 12 drugs associated with incomplete GI absorption and related challenges in predicting the extent of absorption. This approach better mimics the real situation during formulation development where predictive in silico models would be beneficial. Plasma concentration-time profiles for 44 oral drug administrations were calculated by convolution of model-predicted absorption-time profiles and reported pharmacokinetic parameters. Model performance was evaluated by comparing the predicted plasma concentration-time profiles, Cmax, tmax, and exposure (AUC) with observations from clinical studies. The overall prediction accuracies for AUC, given as the absolute average fold error (AAFE) values, were 2.2, 1.6, and 1.3 for Simcyp, GastroPlus, and GI-Sim, respectively. The corresponding AAFE values for Cmax were 2.2, 1.6, and 1.3, respectively, and those for tmax were 1.7, 1.5, and 1.4, respectively. Simcyp was associated with underprediction of AUC and Cmax; the accuracy decreased with decreasing predicted fabs. A tendency for underprediction was also observed for GastroPlus, but there was no correlation with predicted fabs. There were no obvious trends for over- or underprediction for GI-Sim. The models performed similarly in capturing dependencies on dose and particle size. In conclusion, it was shown that all three software packages are useful to guide formulation development. However, as a consequence of the high fraction of inaccurate predictions (prediction error >2-fold) and the clear trend toward decreased accuracy with decreased predicted fabs observed with Simcyp, the results indicate that GI-Sim and GastroPlus perform better than Simcyp in predicting the intestinal absorption of the incompletely absorbed drugs when a higher degree of accuracy is needed. In addition, this study suggests that modeling and simulation research groups should perform systematic model evaluations using their own input data to maximize confidence in model performance and output.
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Affiliation(s)
- Erik Sjögren
- Department of Pharmacy, Uppsala University , Box 580, S-751 23 Uppsala, Sweden
| | - Helena Thörn
- Pharmaceutical Technology and Development, AstraZeneca R&D Gothenburg , SE-43183 Mölndal, Sweden
| | - Christer Tannergren
- Pharmaceutical Technology and Development, AstraZeneca R&D Gothenburg , SE-43183 Mölndal, Sweden
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24
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Du P, Paskaranandavadivel N, Angeli TR, Cheng LK, O'Grady G. The virtual intestine: in silico modeling of small intestinal electrophysiology and motility and the applications. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2015; 8:69-85. [PMID: 26562482 DOI: 10.1002/wsbm.1324] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 10/01/2015] [Accepted: 10/02/2015] [Indexed: 02/06/2023]
Abstract
The intestine comprises a long hollow muscular tube organized in anatomically and functionally discrete compartments, which digest and absorb nutrients and water from ingested food. The intestine also plays key roles in the elimination of waste and protection from infection. Critical to all of these functions is the intricate, highly coordinated motion of the intestinal tract, known as motility, which is coregulated by hormonal, neural, electrophysiological and other factors. The Virtual Intestine encapsulates a series of mathematical models of intestinal function in health and disease, with a current focus on motility, and particularly electrophysiology. The Virtual Intestine is being cohesively established across multiple physiological scales, from sub/cellular functions to whole organ levels, facilitating quantitative evaluations that present an integrative in silico framework. The models are also now finding broad physiological applications, including in evaluating hypotheses of slow wave pacemaker mechanisms, smooth muscle electrophysiology, structure-function relationships, and electromechanical coupling. Clinical applications are also beginning to follow, including in the pathophysiology of motility disorders, diagnosing intestinal ischemia, and visualizing colonic dysfunction. These advances illustrate the emerging potential of the Virtual Intestine to effectively address multiscale research challenges in interdisciplinary gastrointestinal sciences.
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Affiliation(s)
- Peng Du
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | | | - Timothy R Angeli
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Leo K Cheng
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Gregory O'Grady
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
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25
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Harrison SM, Eyres G, Cleary PW, Sinnott MD, Delahunty C, Lundin L. Computational Modeling of Food Oral Breakdown Using Smoothed Particle Hydrodynamics. J Texture Stud 2014. [DOI: 10.1111/jtxs.12062] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | - Graham Eyres
- CSIRO Animal, Food and Health Sciences; North Ryde NSW Australia
| | - Paul W. Cleary
- CSIRO Computational Informatics; Clayton South Vic Australia
| | | | - Conor Delahunty
- CSIRO Animal, Food and Health Sciences; Adelaide SA Australia
| | - Leif Lundin
- CSIRO Animal, Food and Health Sciences; Werribee Vic Australia
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26
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Wiklendt L, Costa M, Dinning PG. Inference of mechanical states of intestinal motor activity using hidden Markov models. BMC PHYSIOLOGY 2013; 13:14. [PMID: 24330642 PMCID: PMC3909344 DOI: 10.1186/1472-6793-13-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 12/05/2013] [Indexed: 11/10/2022]
Abstract
Background Contractions and relaxations of the muscle layers within the digestive tract alter the external diameter and the internal pressures. These changes in diameter and pressure move digesting food and waste products. Defining these complex relationships is a fundamental step for neurogastroenterologists to be able define normal and abnormal gut motility. Results Utilising an in vitro technique that allows for the simultaneous recording of intraluminal pressure (manometry) and gut diameter (video) in an isolated section of rabbit colon, we developed a technique to help define the mechanical states of the muscle at any point in space and time during actual peristaltic movements. This was achieved by directly relating the changes in pressure to the changes in diameter along the length of the gut studied. For each individual measure of pressure or diameter, 3 dynamic state components were identified; increasing or decreasing changes or a stable period. Two additional static state components, fully contracted and fully distended, were defined for the diameter. Then qualitative mechanical states of the muscle activity were defined as combinations of these state components. A hidden Markov model was used to correlate adjacent-in-time samples, and the Viterbi algorithm was used to infer the most likely sequence of mechanical states based on the observed data. From this a spatiotemporal map of the mechanical states was produced, showing the regions of active contractions, active relaxations, or passive states along the length of the gut throughout the entire recording period. Conclusions The identification of mechanical muscles states based on gut diameter and intraluminal pressure was possible by modelling muscle activation with a hidden Markov model.
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Affiliation(s)
| | | | - Phil G Dinning
- Discipline of Human Physiology, Flinders Medical Science and Technology, Flinders University, Adelaide, Australia.
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27
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Cheng LK, Du P, O'Grady G. Mapping and modeling gastrointestinal bioelectricity: from engineering bench to bedside. Physiology (Bethesda) 2013; 28:310-7. [PMID: 23997190 PMCID: PMC3768093 DOI: 10.1152/physiol.00022.2013] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
A key discovery in gastrointestinal motility has been the central role played by interstitial cells of Cajal (ICC) in generating electrical slow waves that coordinate contractions. Multielectrode mapping and multiscale modeling are two emerging interdisciplinary strategies now showing translational promise to investigate ICC function, electrophysiology, and contractions in the human gut.
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Affiliation(s)
- L K Cheng
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.
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28
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Nguyen NQ, Holloway RH, Smout AJ, Omari TI. Automated impedance-manometry analysis detects esophageal motor dysfunction in patients who have non-obstructive dysphagia with normal manometry. Neurogastroenterol Motil 2013; 25:238-45, e164. [PMID: 23113942 DOI: 10.1111/nmo.12040] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Automated integrated analysis of impedance and pressure signals has been reported to identify patients at risk of developing dysphagia post fundoplication. This study aimed to investigate this analysis in the evaluation of patients with non-obstructive dysphagia (NOD) and normal manometry (NOD/NM). METHODS Combined impedance-manometry was performed in 42 patients (27F : 15M; 56.2 ± 5.1 years) and compared with that of 24 healthy subjects (8F : 16M; 48.2 ± 2.9 years). Both liquid and viscous boluses were tested. MATLAB-based algorithms defined the median intrabolus pressure (IBP), IBP slope, peak pressure (PP), and timing of bolus flow relative to peak pressure (TNadImp-PP). An index of pressure and flow (PFI) in the distal esophagus was derived from these variables. KEY RESULTS Diagnoses based on conventional manometric assessment: diffuse spasm (n = 5), non-specific motor disorders (n = 19), and normal (n = 11). Patients with achalasia (n = 7) were excluded from automated impedance-manometry (AIM) analysis. Only 2/11 (18%) patients with NOD/NM had evidence of flow abnormality on conventional impedance analysis. Several variables derived by integrated impedance-pressure analysis were significantly different in patients as compared with healthy: higher PNadImp (P < 0.01), IBP (P < 0.01) and IBP slope (P < 0.05), and shorter TNadImp_PP (P = 0.01). The PFI of NOD/NM patients was significantly higher than that in healthy (liquid: 6.7 vs 1.2, P = 0.02; viscous: 27.1 vs 5.7, P < 0.001) and 9/11 NOD/NM patients had abnormal PFI. Overall, the addition of AIM analysis provided diagnoses and/or a plausible explanation in 95% (40/42) of patients who presented with NOD. CONCLUSIONS & INFERENCES Compared with conventional pressure-impedance assessment, integrated analysis is more sensitive in detecting subtle abnormalities in esophageal function in patients with NOD and normal manometry.
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Affiliation(s)
- N Q Nguyen
- Department of Gastroenterology and Hepatology, Royal Adelaide Hospital, Adelaide, SA, Australia.
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Arkwright JW, Dickson A, Maunder S, Blenman N, Lim J, O’Grady G, Archer R, Costa M, Spencer NJ, Brookes S, Pullan A, Dinning PG. The effect of luminal content and rate of occlusion on the interpretation of colonic manometry. Neurogastroenterol Motil 2013; 25:e52-9. [PMID: 23228077 PMCID: PMC3539177 DOI: 10.1111/nmo.12051] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
BACKGROUND Manometry is commonly used for diagnosis of esophageal and anorectal motility disorders. In the colon, manometry is a useful tool, but clinical application remains uncertain. This uncertainty is partly based on the belief that manometry cannot reliably detect non-occluding colonic contractions and, therefore, cannot identify reliable markers of dysmotility. This study tests the ability of manometry to record pressure signals in response to non-lumen-occluding changes in diameter, at different rates of wall movement and with content of different viscosities. METHODS A numerical model was built to investigate pressure changes caused by localized, non-lumen-occluding reductions in diameter, similar to those caused by contraction of the gut wall. A mechanical model, consisting of a sealed pressure vessel which could produce localized reductions in luminal diameter, was used to validate the model using luminal segments formed from; (i) natural latex; and (ii) sections of rabbit proximal colon. Fluids with viscosities ranging from 1 to 6800 mPa s(-1) and luminal contraction rates over the range 5-20 mmHg s(-1) were studied. KEY RESULTS Manometry recorded non-occluding reductions in diameter, provided that they occurred with sufficiently viscous content. The measured signal was linearly dependent on the rate of reduction in luminal diameter and also increased with increasing viscosity of content (R(2) = 0.62 and 0.96 for 880 and 1760 mPa s(-1), respectively). CONCLUSIONS & INFERENCES Manometry reliably registers non-occluding contractions in the presence of viscous content, and is therefore a viable tool for measuring colonic motility. Interpretation of colonic manometric data, and definitions based on manometric results, must consider the viscosity of luminal content.
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Affiliation(s)
- J. W. Arkwright
- CSIRO Materials Science and Engineering, Bradfield Road, Lindfield, NSW 2070, Australia
| | - A. Dickson
- CSIRO Materials Science and Engineering, Bradfield Road, Lindfield, NSW 2070, Australia,Queensland University of Technology, Science and Engineering Faculty, PO Box 2434, Brisbane, QLD 4001
| | - S. Maunder
- CSIRO Materials Science and Engineering, Bradfield Road, Lindfield, NSW 2070, Australia
| | - N. Blenman
- CSIRO Materials Science and Engineering, Bradfield Road, Lindfield, NSW 2070, Australia
| | - J. Lim
- University of Auckland, Bioengineering Institute, University of Auckland, New Zealand
| | - G. O’Grady
- University of Auckland, Bioengineering Institute, University of Auckland, New Zealand,Dept of Surgery & Bioengineering Institute, University of Auckland, New Zealand
| | - R. Archer
- University of Auckland, Department of Engineering Science, University of Auckland, New Zealand
| | - M. Costa
- Department of Human Physiology, Flinders University, Bedford Park, Australia
| | - N. J. Spencer
- Department of Human Physiology, Flinders University, Bedford Park, Australia
| | - S. Brookes
- Department of Human Physiology, Flinders University, Bedford Park, Australia
| | - A. Pullan
- University of Auckland, Bioengineering Institute, University of Auckland, New Zealand,University of Auckland, Department of Engineering Science, University of Auckland, New Zealand
| | - P. G. Dinning
- Department of Human Physiology, Flinders University, Bedford Park, Australia
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