Understanding the correlation between tissue architecture, health status, and mechanical properties is essential for improving material models and developing tissue engineering scaffolds. Since structural-based material models are state of the art, there is an urgent need for experimentally obtained structural parameters. For this purpose, the medial layer of nine human abdominal aortas was simultaneously subjected to equibiaxial loading and multi-photon microscopy. At each loading interval of 0.02, collagen and elastin fibers were imaged based on their second-harmonic generation signal and two-photon excited autofluorescence, respectively. The structural alterations in the fibers were quantified using the parameters of orientation, diameter, and waviness. The results of the mechanical tests divided the sample cohort into the ruptured and non-ruptured, and stiff and non-stiff groups, which were covered by the findings from histological investigations. The alterations in structural parameters provided an explanation for the observed mechanical behavior. In addition, the waviness parameters of both collagen and elastin fibers showed the potential to serve as indicators of tissue strength. The data provided address deficiencies in current material models and bridge multiscale mechanisms in the aortic media. STATEMENT OF SIGNIFICANCE: Available material models can reproduce, but cannot predict, the mechanical behavior of human aortas. This deficiency could be overcome with the help of experimentally validated structural parameters as provided in this study. Simultaneous multi-photon microscopy and biaxial extension testing revealed the microstructure of human aortic media at different stretch levels. Changes in the arrangement of collagen and elastin fibers were quantified using structural parameters such as orientation, diameter and waviness. For the first time, structural parameters of human aortic tissue under continuous loading conditions have been obtained. In particular, the waviness parameters at the reference configuration have been associated with tissue stiffness, brittleness, and the onset of atherosclerosis.
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http://dx.doi.org/10.1016/j.actbio.2022.08.017 | DOI Listing |
Ann Biomed Eng
December 2024
Eco-Friendly Smart Ship Parts Technology Innovation Center, Pusan National University, Busan, Republic of Korea.
Shins are one of the most vulnerable bones in human body. Shin guards are evaluated by their effectiveness in reducing the force applied to the bone. In this study, a structural modified mechanical lumped model of the shin guard was developed to provide maximum force distribution using physical parameter change modification technique and genetic algorithm.
View Article and Find Full Text PDFBone
December 2024
McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada; Department of Biomedical Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB, Canada; Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada. Electronic address:
ACL injuries commonly lead to post-traumatic osteoarthritis (PTOA), but the underlying mechanism is not well-understood. One theorized mechanism is pathological bone remodelling following an ACL tear, for which high-resolution peripheral quantitative computed tomography (HR-pQCT) is uniquely positioned to investigate in vivo in humans. In this study, we longitudinally investigate the one-year changes in periarticular bone density and microarchitecture in the human knee following an ACL tear and reconstructive surgery using data sampled from an on-going observational cohort study.
View Article and Find Full Text PDFTalanta
December 2024
Department of Vascular Surgery, Zhongshan Xiamen Hospital, Fudan University, Xiamen, 361015, China. Electronic address:
Filling the microchannel with negatively charged hydrogel can exhibit microsacle ion current rectification (ICR) behavior, which is attributed to the space negative charge and structural asymmetry of hydrogel. In this study, this character had been applied to develop a trypsin sensor for the first time. A hydrogel synthesized with bovine serum albumin (BSA) and glyoxal (BSAG hydrogel) was filled at the tip of microchannel firstly.
View Article and Find Full Text PDFJ Comput Chem
January 2025
Laboratoire d'Optique et Biosciences (CNRS UMR7645, INSERM U1182), Ecole Polytechnique, Institut polytechnique de Paris, Palaiseau, France.
Folates comprise a crucial class of biologically active compounds related to folic acid, playing a vital role in numerous enzymatic reactions. One-carbon metabolism, facilitated by the folate cofactor, supports numerous physiological processes, including biosynthesis, amino acid homeostasis, epigenetic maintenance, and redox defense. Folates share a common pterin heterocyclic ring structure capable of undergoing redox reactions and existing in various protonation states.
View Article and Find Full Text PDFInt Immunopharmacol
December 2024
Tianjin Nankai Hospital, Tianjin Medical University, Tianjin, China; Institute of Integrative Medicine for Acute Abdominal Diseases, Tianjin, China; Tianjin Key Laboratory of Acute Abdomen Disease Associated Organ Injury and ITCWM Repair, Tianjin, China. Electronic address:
Background: Sepsis is a life-threatening condition involving organ dysfunction characterized by a generalized inflammatory syndrome, and the associated mortality rate is high. Electroacupuncture (EA) exerts benefits in endotoxemia-induced lung injury, mainly through lung inflammation reduction and cellular homeostasis, although the anti-inflammatory mechanisms underlying these benefits remain to be completely understood.
Methods: Mice were pretreated with EA or sham EA therapy 5 days prior to the induction of endotoxemia through the administration of lipopolysaccharide (LPS) and cecal ligation and puncture (CLP).
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