Molecular Biomechanics Research Articles

Rapid detection of food microorganisms from the perspective of cellular and molecular biomechanics leveraging biotechnology and computer vision

Rapid detection of food microorganisms from the perspective of cellular and molecular biomechanics leveraging biotechnology and computer vision

Cloud-based adolescent physical health research incorporating cell molecular biomechanics insights into predictive modeling and biometric algorithms

The physical health of adolescents is critical to their future development and quality of life. However, there is still much room for improvement in monitoring and intervention of adolescent physical health in colleges and universities. Based on the National Standard for Student Physical Fitness and Health, this study proposes a physical health management framework for adolescents that combines a cloud platform and real-time data analysis. Through an innovative health monitoring and early warning system and feedback mechanism, the effectiveness of health intervention was significantly improved. Body mass index is related to the balance between energy intake and expenditure at the cellular level. Excessive calorie intake can lead to an increase in adipose cells, which secrete molecules that can affect overall metabolism and biomechanical stress on tissues. Lung capacity is linked to the elasticity and strength of the alveolar cells and the connective tissue in the lungs. he proper functioning of these cells, regulated by intracellular signaling pathways and molecular interactions, determines the efficiency of gas exchange. The 50-meter run, seated forward bending, standing long jump, pull-ups/sit-ups, and 800-meter/1000-meter run all involve muscle contractions. Muscle cells contain actin and myosin filaments, and the sliding of these filaments, regulated by calcium ions and other molecular signals, generates the force required for movement. The graded early warning parameters established by the system can thus be seen as indicators of potential disruptions in these cell molecular biomechanical processes. The innovative health monitoring and early warning system and feedback mechanism not only help students recognize the weaknesses in their physical functions from a macroscopic level but also potentially identify areas where cell molecular biomechanical imbalances may exist. This enables physical education teachers to formulate personalized training plans that can target and correct these imbalances, as experimentally validated by the system's ability to accurately identify health risks and enhance the overall health of students.

Biomechanics based computer simulation of rural landscape design using remote sensing image technology

Introduction: The strategy and restoration of rural areas and landscape in biomechanics, with a particular emphasis on cellular and molecular biomechanics, is crucial for sustainable rural landscape design. At the cellular and molecular level, plants’ biomechanical properties, such as the rigidity and elasticity of cell walls, determine their growth patterns and responses to environmental factors. These properties are essential in understanding how plants can be effectively incorporated into the rural landscape to enhance its stability and functionality. Aim: The objective of this research is to develop a novel computer simulation model for rural landscape planning using remote sensing imaging technology. Research methodology: We introduce a novel Adaptive YOLOv7 method driven by Starling Murmuration search. UAVs are used to collect extensive visual data for training the model. By considering cellular and molecular biomechanics, we can analyze how the mechanical forces within plants affect their ability to resist wind, retain water, and interact with the surrounding soil and other organisms. This knowledge can be integrated into the model to better predict the long-term viability and adaptability of different plant species in the rural landscape. The combination of the 3D GIS virtual image strategy model and our proposed model, along with SM optimization, not only improves object identification but also takes into account the biomechanical aspects for more accurate simulations. Crowdsourcing helps in precisely mapping rural landscapes and structures, while the incorporation of biomechanical principles ensures better adaptability to changing environmental and ecological conditions. Findings and Conclusion: Implemented in Python software, our SM-AYOLOv7 model shows excellent performance, with metrics like f1 score (93.64%), recall (92.34%), accuracy (91.72%), and IoU (90.23%). Our method outperforms conventional ones, demonstrating enhanced accuracy and flexibility, especially in handling changing configurations, due to the integration of cellular and molecular biomechanical insights.

Characteristics and cellular and molecular biomechanical influencing factors of resilience: A cross-sectional study of nurses experiencing workplace violence in Jiangsu China

Objective: To investigate the resilience status of nurses after workplace violence and its influencing factors from the perspective of cellular and molecular biomechanics. Methods: From April to July 2024, a cross-sectional questionnaire study was conducted utilizing the General Information Questionnaire, the Medical Staff Resilience Scale (MSRS), the Workplace Violence Scale (WVS), the General Self-Efficacy Scale (GSE), and the Perceived Social Support Scale (PSSS) on a sample of 375 nurses who had been victims of workplace violence at six tertiary-level A general hospitals and three secondary-level hospitals in Jiangsu Province, China. The data were subsequently analyzed. Results: The nurses’ resilience score was (72.37 ± 10.19) with a mean score of (4.02 ± 0.57). Multiple regression analysis showed that age, work experience, title, monthly income, self-efficacy, and social support independently influenced their resilience. (P < 0.05). Pearson’s correlation analysis revealed a positive correlation between carers’ levels of resilience with generic self-efficacy scale and social support (P < 0.01), and a negative correlation of resilience with workplace violence (P < 0.01). Conclusion: The resilience scores of nurses who had suffered workplace violence were found to be at a moderate level. Stressors from workplace violence might trigger complex intracellular signaling pathways and molecular changes in nerve cells and endocrine cells of nurses. Hormonal imbalances could further affect neurotransmitter systems and molecular cascades related to mood regulation and stress adaptation, thereby influencing the nurses’ resilience. Higher self-efficacy could potentially enhance the activation of positive molecular pathways and the expression of certain genes related to stress resistance. Social support might buffer the negative impacts of workplace violence on cellular and molecular mechanisms by providing additional resources and positive molecular signals. It is recommended that managers consider the effects of age, years of work experience, job title, and monthly income when developing strategies to enhance resilience. It is also the responsibility of managers to facilitate the mobilization of resources, both internal and external, related to self-efficacy and social support. Furthermore, they should construct targeted training courses based on an analysis of the mechanisms involved in the occurrence of workplace violence, to improve the resilience of nurses.

Comparative analysis of biomechanical characteristics of knee flexion and extension muscles in volleyball physical training

This study aimed to analyze the biomechanical characteristics of knee flexion and extension muscles in volleyball physical training from the cellular and molecular biomechanics aspect. Multiple training modes like strength, elasticity, and comprehensive training were chosen to systematically evaluate relevant characteristics of these muscles among volleyball players. Advanced devices such as 3D motion capture systems, ground reaction force platforms, and electromyography equipment were used to gather precise biomechanical data. At the cellular and molecular level, different trainings impact muscle cells differently. For example, strength training might enhance the synthesis of contractile proteins within cells, while elasticity training could influence the elasticity-related molecular structures. With multidimensional data analysis, the effects of various training modes were compared. The comprehensive training group had a kinematic flexion extension angle of 528.27º ± 11.49º, an angular velocity of 135.52º ± 5.97º, and an angular acceleration of 3177.02º ± 116.88º, performing best. This could be due to its comprehensive influence on cellular and molecular processes in muscles, promoting better coordination and force generation. This article offers a theoretical basis for volleyball players to create scientific training plans and gives practical tips for coaches and athletes to optimize programs and prevent injuries. By focusing on cellular and molecular biomechanics, it fills research gaps and helps boost the development of biomechanics in volleyball physical training.

Analyzing the influence of physical posture on audience perception in mass media presentations

Non-verbal communication, especially physical posture, affects audience perception. From a cellular and molecular biomechanics angle, different postures may trigger unique intracellular responses. Upright or leaning forward postures might activate neural pathways that enhance neurotransmitter release related to positive perception. In contrast, a slouched posture could disrupt normal cellular signaling, potentially leading to a less favorable audience perception. This study explores the impact of four postures on audience views in a media setting, aiming to offer data on how posture shapes key perceptions and provide valuable insights for Mass-media Presentations (MMP), despite limited prior research on this aspect. A within-subject experimental design was employed, with 34 participants observing media presentations under four posture conditions. Posture was the independent variable, while credibility, trustworthiness, engagement, and authority were the dependent variables. Data were collected using surveys, posture monitoring devices, and eye-tracking data. Statistical analyses, including Analysis of Variance (ANOVA) and paired t-tests, were conducted to determine significant differences between posture conditions. Upright and leaning forward postures were associated with the highest audience ratings for credibility, trustworthiness, engagement, and authority. Slouched posture consistently led to the lowest ratings across all measures. The ANOVA results revealed significant differences in perceptions of engagement (F = 10.21, p = 0.0008) and credibility (F = 8.67, p = 0.0013). Paired t-tests and post-hoc analyses confirmed that upright posture significantly outperformed slouched posture across all metrics, with large effect sizes (Cohen’s d > 1.0). Posture significantly influences audience perceptions in mass media presentations. Upright and leaning forward postures enhance credibility, trustworthiness, engagement, and authority, while slouched posture diminishes these perceptions. These findings provide practical insights for media professionals, suggesting that careful attention to posture can improve the effectiveness of media presentations. Future research could investigate how gestures and facial expressions interact with these cellular and molecular mechanisms to shape audience engagement.

Atomic Force Microscopy (AFM) Applications in Arrhythmogenic Cardiomyopathy.

Arrhythmogenic cardiomyopathy (ACM) is an inherited heart muscle disorder characterized by progressive replacement of cardiomyocytes by fibrofatty tissue, ventricular dilatation, cardiac dysfunction, arrhythmias, and sudden cardiac death. Interest in molecular biomechanics for these disorders is constantly growing. Atomic force microscopy (AFM) is a well-established technic to study the mechanobiology of biological samples under physiological and pathological conditions at the cellular scale. However, a review which described all the different data that can be obtained using the AFM (cell elasticity, adhesion behavior, viscoelasticity, beating force, and frequency) is still missing. In this review, we will discuss several techniques that highlight the potential of AFM to be used as a tool for assessing the biomechanics involved in ACM. Indeed, analysis of genetically mutated cells with AFM reveal abnormalities of the cytoskeleton, cell membrane structures, and defects of contractility. The higher the Young’s modulus, the stiffer the cell, and it is well known that abnormal tissue stiffness is symptomatic of a range of diseases. The cell beating force and frequency provide information during the depolarization and repolarization phases, complementary to cell electrophysiology (calcium imaging, MEA, patch clamp). In addition, original data is also presented to emphasize the unique potential of AFM as a tool to assess fibrosis in cardiac tissue.

Molecular Biomechanics Controls Protein Mixing and Segregation in Adherent Membranes.

Cells interact with their environment by forming complex structures involving a multitude of proteins within assemblies in the plasma membrane. Despite the omnipresence of these assemblies, a number of questions about the correlations between the organisation of domains and the biomechanical properties of the involved proteins, namely their length, flexibility and affinity, as well as about the coupling to the elastic, fluctuating membrane, remain open. Here we address these issues by developing an effective Kinetic Monte Carlo simulation to model membrane adhesion. We apply this model to a typical experiment in which a cell binds to a functionalized solid supported bilayer and use two ligand-receptor pairs to study these couplings. We find that differences in affinity and length of proteins forming adhesive contacts result in several characteristic features in the calculated phase diagrams. One such feature is mixed states occurring even with proteins with length differences of 10 nm. Another feature are stable nanodomains with segregated proteins appearing on time scales of cell experiments, and for biologically relevant parameters. Furthermore, we show that macroscopic ring-like patterns can spontaneously form as a consequence of emergent protein fluxes. The capacity to form domains is captured by an order parameter that is founded on the virial coefficients for the membrane mediated interactions between bonds, which allow us to collapse all the data. These findings show that taking into account the role of the membrane allows us to recover a number of experimentally observed patterns. This is an important perspective in the context of explicit biological systems, which can now be studied in significant detail.

MOLECULAR BIOLOGY AND BIOMECHANICS OF OSTEOPHYTE FORMATION IN ELBOW OSTEOARTHRITIS: A REVIEW

Managing osteophyte in elbow osteoarthritis (OA) is not an easy task. In the review of the subject hereby, the molecular biology and biomechanics of osteophyte formation will be addressed in composite detail. A number of basic and clinical science research studies that have evaluated the importance and significant role of growth factors, cytokines production, receptors expression, proteoglycans, and alarmins secretion will be included. At the same time, it is notable that the osteophyte formation has not been thoroughly evaluated with respect to its biomechanics, stress and strain pattern on the joint, and its relation to growth plate and the differences that may exist between animal and human joints. Namely, a few studies have begun to look at this particular aspect of osteophyte formation, which does not cover the issue of the graded biomechanical response to the osteophyte formation. The findings of this study can conclude that biomechanical understanding of osteophyte formation has the potential to give a better solution for medical and surgical management of osteophyte formation in different joints and particularly in elbow joint. As such, the proper management of elbow OA with its significant osteophyte formation requires a comprehensive understanding of biology and biomechanics of osteophyte formation.

Next Generation Methods for Single-Molecule Force Spectroscopy on Polyproteins and Receptor-Ligand Complexes.

Single-molecule force spectroscopy with the atomic force microscope provides molecular level insights into protein function, allowing researchers to reconstruct energy landscapes and understand functional mechanisms in biology. With steadily advancing methods, this technique has greatly accelerated our understanding of force transduction, mechanical deformation, and mechanostability within single- and multi-domain polyproteins, and receptor-ligand complexes. In this focused review, we summarize the state of the art in terms of methodology and highlight recent methodological improvements for AFM-SMFS experiments, including developments in surface chemistry, considerations for protein engineering, as well as theory and algorithms for data analysis. We hope that by condensing and disseminating these methods, they can assist the community in improving data yield, reliability, and throughput and thereby enhance the information that researchers can extract from such experiments. These leading edge methods for AFM-SMFS will serve as a groundwork for researchers cognizant of its current limitations who seek to improve the technique in the future for in-depth studies of molecular biomechanics.

Extending the Capabilities of Molecular Force Sensors via DNA Nanotechnology.

At the nanoscale, pushing, pulling, and shearing forces drive biochemical processes in development and remodeling as well as in wound healing and disease progression. Research in the field of mechanobiology investigates not only how these loads affect biochemical signaling pathways but also how signaling pathways respond to local loading by triggering mechanical changes such as regional stiffening of a tissue. This feedback between mechanical and biochemical signaling is increasingly recognized as fundamental in embryonic development, tissue morphogenesis, cell signaling, and disease pathogenesis. Historically, the interdisciplinary field of mechanobiology has been driven by the development of technologies for measuring and manipulating cellular and molecular forces, with each new tool enabling vast new lines of inquiry. In this review, we discuss recent advances in the manufacturing and capabilities of molecular-scale force and strain sensors. We also demonstrate how DNA nanotechnology has been critical to the enhancement of existing techniques and to the development of unique capabilities for future mechanosensor assembly. DNA is a responsive and programmable building material for sensor fabrication. It enables the systematic interrogation of molecular biomechanics with forces at the 1- to 200-pN scale that are needed to elucidate the fundamental means by which cells and proteins transduce mechanical signals.

Preface: Innovations and Current Trends in Computational Cardiovascular Modeling and Beyond: Molecular, Cellular, Tissue and Organ Biomechanics with Clinical Applications

Preface: Innovations and Current Trends in Computational Cardiovascular Modeling and Beyond: Molecular, Cellular, Tissue and Organ Biomechanics with Clinical Applications

Molecular biology and biomechanics to understand focal adhesions

Molecular biology and biomechanics to understand focal adhesions

Early-Onset Hypertrophic Cardiomyopathy Mutations Significantly Increase the Velocity, Force, and Actin-Activated ATPase Activity of Human β-Cardiac Myosin

Hypertrophic cardiomyopathy (HCM) is a heritable cardiovascular disorder that affects 1 in 500 people. A significant percentage of HCM is attributed to mutations in β-cardiac myosin, the motor protein that powers ventricular contraction. This study reports how two early-onset HCM mutations, D239N and H251N, affect the molecular biomechanics of human β-cardiac myosin. We observed significant increases (20%-90%) in actin gliding velocity, intrinsic force, and ATPase activity in comparison to wild-type myosin. Moreover, for H251N, we found significantly lower binding affinity between the S1 and S2 domains of myosin, suggesting that this mutation mayfurther increase hyper-contractility by releasing active motors. Unlike previous HCM mutations studied at the molecular level using human β-cardiac myosin, early-onset HCM mutations lead to significantly larger changes in the fundamental biomechanical parameters and show clear hyper-contractility.

Leukocyte arrest: Biomechanics and molecular mechanisms of β2 integrin activation.

Integrins are a group of heterodimeric transmembrane receptors that play essential roles in cell-cell and cell-matrix interaction. Integrins are important in many physiological processes and diseases. Integrins acquire affinity to their ligand by undergoing molecular conformational changes called activation. Here we review the molecular biomechanics during conformational changes of integrins, integrin functions in leukocyte biorheology (adhesive functions during rolling and arrest) and molecules involved in integrin activation.

Society Awards 2014

Society Awards 2014

Investigating Force-Induced Structural Changes in Single Collagen Molecules

Collagen is a structural protein found in abundance throughout the body, within the extracellular matrix and connective tissues including skin, bone, and tendons. One of the functions of collagen is to maintain tissue structure in the presence of external forces. However the effect of force on the collagen's structure is not clear:1 in the presence of an external force, collagen has been proposed to have one of two opposing structural changes: either overwinding, reducing its cleavage2 or underwinding, increasing its cleavage.3 Using a high-throughput single-molecule stretching instrument, the centrifuge force microscope (CFM),4 we are developing a technique to investigate force-dependent structural changes of collagen under various loading conditions. Here, we report on our progress tethering, enzymatically cleaving and applying a tunable external force to single molecules of collagen. In addition, we present characterization of the instrument and technique accomplished with single DNA molecules.1.Chang, S.W. and Buehler M. (2014) Molecular biomechanics of collagen molecules. Mat. Today. 17, 70-76.2.Camp, R., Liles, M., Beale, J., Saeidi, N., Flynn, BP., Moore, E., Murthy, S., and Ruberti, JW. (2011) Molecular Mechanochemistry: Low Force Switch Slows Enzymatic Cleavage of Human Type I Collagen Monomer. JACS, 133, 4073-8.3.Adhikari, A., Glassey, E. and Dunn, AR. (2012) Conformation Dynamics Accompanying the Proteolytic Degradation of Trimeric Collagen I by Collagenases. JACS, 134, 13259-65.4.Halvorsen, K. and Wong, W. (2010) Massively Parallel Single-Molecule Manipulation Using Centrifugal Force. Biophys J., 98, L53-L55.

Progress in measuring biophysical properties of membrane proteins with AFM single-molecule force spectroscopy

Membrane proteins are crucial in cell physiological activities and are the targets for most drugs. Thus, investigating the behaviors of membrane proteins not only provide deeper insights into cell function, but also help disease treatment and drug development. Atomic force microscopy is a unique tool for investigating the structure of membrane proteins. It can both image the morphology of single native membrane proteins with high resolution and, via single-molecule force spectroscopy (SMFS), directly measure their biophysical properties during molecular physiological activities such as ligand binding and protein unfolding. In the context of molecular biomechanics, SMFS has been successfully used to understand the structure and function of membrane proteins, complementing the static three-dimensional structures of proteins obtained by X-ray crystallography. Here, based on the authors’ antigen-antibody binding force measurements in clinical tumor cells, the principle and method of SMFS is discussed, the progress in using SMFS to characterize membrane proteins is summarized, and challenges for SMFS are presented.

Mechanochemitry: A Molecular Biomechanics View of Mechanosensing

Molecular biomechanics includes two themes: the study of mechanical aspects of biomolecules and the study of molecular biology of the cell using mechanical tools. The two themes are interconnected for obvious reasons. The present review focuses on one of the interconnected areas-the mechanical regulation of molecular interaction and conformational change. Recent conceptual developments are summarized, including catch bonds, regulation of molecular interaction by the history of force application, and cyclic mechanical reinforcement. These studies elucidate the mechanochemistry of some of the candidate mechanosensing molecules, thereby providing a natural connection to mechanobiology.

Review series – Mechanotransduction from physiology to disease states

Traditional boundaries between engineering and life sciences are rapidly disintegrating as interdisciplinary research teams develop new engineering tools for exploring fundamental issues in both medicine and biology. The initial innovation for biomechanics was primarily developed to study the function of human tissues. With recent technological advances in multiple research fields such as cell biology, molecular biology, as well as micro-/nanotechnology, much attention is shifting to probe the functionality of mechanics at the cellular and molecular levels. The pursuit of this direction helps to reveal the mechanisms of and therapeutic potentials for some of the most lethal diseases, including cardiovascular diseases, organ fibrosis and cancer. This interdisciplinary approach has generated great interests among researchers working in a wide variety of communities, including industry, universities and research laboratories. In this connection, a fair amount of evidence has been recently accumulated to indicate that physical-based stimuli (e.g. the mechanical interactions between cells and their microenvironments) play a crucial role in cancer biology with the developments of various physical, chemical or biological approaches. We initialized discussions with Prof. Laurentiu M. Popescu, the Editor-in-Chief of Journal of Cellular and Molecular Medicine, about the organization of a ‘Review Series’ in 2012, focusing on several specific issues in cellular and molecular biomechanics (mechanobiology). The issues regarding mechanobiology in this Review Series that we have addressed cover physiology (cardiac physiology, haemostasis and thrombosis and neurosensory mechanotransduction), cell biology (cell adhesion and migration, stem cell differentiation) and pathology (cancer development, skin disorders and degeneration and vascular pathobiology). Here, we would like to show our deep appreciations to all authors and reviewers. Without their greatest help and contributions, this Review Series would not be published on time. This Review Series may not cover all issues in this emerging scientific field. However, we believe that our efforts have a great potential ‘to hurl a boulder to draw a jade ()' and ignite the innovations and challenging discussions in this field. Chao-Min Cheng received his Ph.D. in 2009 from Carnegie Mellon University (Biomedical Engineering Department); he then did his post-doctoral training with Prof. George M. Whitesides at Harvard University to develop paper diagnostic systems for global public health. He is currently an independent P.I. at National Tsing Hua University, Taiwan, starting from 2011 summer. He has been blessed to receive the Traveling Fellowship in Journal of Cell Science, and Distinguished Young Investigator Research Grant from National Science Council in Taiwan. He was also an invited attendee for NAS Sackler Colloquium at the National Academy of Sciences, and research highlighted in the National Academies – Keck Futures Initiative, Scientific American, Chemistry World and New York Times. His general research interests focus on cellular and molecular biomechanics and mechanotransduction, paper diagnostic systems for public health (including the development of sensing elements) and biomedical devices for cellular and molecular biology. He is also currently an acting member for International Affairs/Globalization Committee at Biomedical Engineering Society (BMES) and Editorial Board member in Sensor Letters. Ming-Jer Tang is currently the Distinguished Professor of Physiology, National Cheng Kung University Medical College, Tainan, Taiwan. He received his M.D. from Taipei Medical College, Taiwan in 1980 and then Ph.D. in Physiology from University of Michigan, Ann Arbor in 1987. After 3 years Post-doctoral Fellowship at UM and University of Southern California Medical School, he came back to his hometown and joined National Cheng Kung University in 1990. He was the Associate Professor from 1990 to 1996, Professor from 1996 to 2002 and Distinguished Professor since 2002 in Department of Physiology, National Cheng Kung University Medical College. His research and teaching interests have been renal physiology, tissue engineering and regenerative medicine. His laboratory has unravelled the functions of and interactions between two collagen receptors, i.e. α2β1 integrin and DDR1, in epithelial cell differentiation. His current research is to explore mechanobiology of cancer and fibrosis of the tissues. He has a long-term experience in academic administration. He was Executive Vice Dean of National Cheng Kung University Medical College from 2001 to 2007 and Vice President of Academic Affairs for National Cheng Kung University from 2007 to 2011. He is now President of Tunghai University, the first Liberal Arts University in Taiwan.