Article
Chemistry, Physical
Rita Ungai-Salanki, Benjamin Csippa, Tamas Gerecsei, Beatrix Peter, Robert Horvath, Balint Szabo
Summary: This research investigated the physical background of biomolecular adhesion force through experiments and simulations, taking into account the impact of targeting offset on the results. The findings revealed that a higher targeting offset led to an increase in lifting force, while increasing flow rate actually decreased the lifting force. After reaching the maximum lifting force, further increasing the flow rate did not enhance the micropipette's manipulation force on the microbeads.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Engineering, Mechanical
Vu Linh Nguyen
Summary: This paper presents a new design of a novel adjustable constant-force mechanism (CFM) using a geared Sarrus linkage and a linear spring. The design provides a constant force over a wide range of displacement and allows energy-free adjustment by varying the spring position without preload. Construction, geometric constraints, and constant-force design are explained, and desired parameters with consideration of gear friction are determined. Experimental studies on a prototype of the CFM show a constant force of up to 20 N within a stroke of 140 mm, with a force error of less than 6%.
MECHANISM AND MACHINE THEORY
(2023)
Review
Biochemistry & Molecular Biology
Alla Kalmykova
Summary: The stability of telomeres plays a crucial role in maintaining genome integrity across generations. Telomere dysfunction can lead to changes in cell fate, regardless of telomere length. The multiple tandem repeats in telomeres have the potential for recombination. Telomere stability requires heterochromatin formation, transcriptional repression, suppression of homologous recombination, and chromosome end protection. Genetic and epigenetic defects affecting telomere homeostasis can cause length-independent internal telomeric DNA damage. Telomeres, regardless of their length, serve as primary sensors of genome instability and can trigger cell death or developmental arrest. Telomeric RNAs have been found to play a signaling role in cell fate and early development. The telomere checkpoint mechanism ensures genome stability but accelerates the aging process.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biophysics
Susav Pradhan, Raoul Solomon, Ankita Gangotra, Gleb E. Yakubov, Geoff R. Willmott, Catherine P. Whitby, Tracy K. Hale, Martin A. K. Williams
Summary: This study investigates the changes in material properties of nuclei extracted from MCF7 cells after knockdown of HP1α, showing that HP1α depletion significantly reduces the apparent Young's moduli of the cell nuclei. Additionally, different mechanical properties of the nuclei were observed when using different techniques, indicating that various components within the nuclei impact the overall mechanical response differently.
BIOPHYSICAL JOURNAL
(2021)
Article
Biochemistry & Molecular Biology
Gaelle Houthaeve, Gerardo Garcia-Diaz Barriga, Stephan Stremersch, Herlinde De Keersmaecker, Juan Fraire, Jo Vandesompele, Pieter Mestdagh, Stefaan De Smedt, Kevin Braeckmans, Winnok H. De Vos
Summary: The study investigates the effects of VNB photoporation on cell homeostasis, finding that A-type lamins are upregulated after photoporation and contribute to the recovery of the nucleus. Selective depletion of A-type lamins reduces cell viability, while stimulation of LMNA transcription increases the survival rate of successfully transfected cells.
CELLULAR AND MOLECULAR LIFE SCIENCES
(2022)
Article
Chemistry, Analytical
Tamas Gerecsei, Peter Chrenko, Nicolett Kanyo, Beatrix Peter, Attila Bonyar, Inna Szekacs, Balint Szabo, Robert Horvath
Summary: This study utilized a computer-controlled micropipette (CCMP) to measure the dissociation constant (K-d) of integrin-RGD binding, combined with techniques such as surface coating and local flow inducing hydrodynamic lifting force to study cell adhesion behavior. The results demonstrated that CCMP could effectively characterize cell adhesion at both single-cell and whole population levels, offering a convenient and automated approach for quantifying cell adhesivity before further processing.
Article
Robotics
Zhongchao Zhou, Shota Kokubu, Yuanyuan Wang, Yuxi Lu, Pablo Enrique Tortos, Wenwei Yu
Summary: This study designed a method to find the optimal spring constant based on gradient descent algorithm, and verified that it could improve control accuracy of PAMs. The study provides insights to practical use of soft actuators.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2022)
Article
Biology
Andria C. Schibler, Predrag Jevtic, Gianluca Pegoraro, Daniel L. Levy, Tom Misteli
Summary: The size and shape of the human cell nucleus varies greatly among different cell types and tissues. Changes in nuclear morphology are associated with diseases including cancer, as well as aging. However, the factors that determine nuclear shape and size are not well understood. Through a comprehensive screening, we identified a set of novel regulators of nuclear morphology and found that the interaction between lamin A and histone H3 plays an important role in nuclear shape.
Article
Automation & Control Systems
Yuzhang Wei, Qingsong Xu
Summary: Cell microinjection is crucial in the biomedical domain. A new force-sensing cell microinjector with novel compliant small-stiffness mechanism is proposed in this article, which enables high sensing sensitivity and large loading capability. The mechanism combines a constant-force mechanism with a small positive-stiffness mechanism to remove intercept force well.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2021)
Article
Engineering, Mechanical
Fuliang Niu, Zhen Liu, Haibo Gao, Haitao Yu, Nan Li, Zongquan Deng
Summary: The study focuses on the dynamic constant-force performance in suspended astronaut micro-gravity simulation systems, and achieves enhanced system performance by improving lightweight low-stiffness mechanism and setting force adjusting mechanism.
MECHANISM AND MACHINE THEORY
(2022)
Article
Biochemical Research Methods
Yanqi Wu, Alastair G. Stewart, Peter V. S. Lee
Summary: This study developed a high-throughput microfluidic compressibility cytometry approach using multi-tilted-angle surface acoustic wave for rapid measurement of thousands of single-cell compressibility. Experimental validation and characterization of tumor cells showed the potential utility of high-throughput mechanophenotyping.
Article
Engineering, Mechanical
Anna Christina Thewes, Philip Schmitt, Philipp Loehler, Martin Hoffmann
Summary: This paper introduces an electrostatic constant-force actuator for tissue characterization, combining a comb drive structure and a constant-force spring system. Theoretical overview, actual measurements, and fabrication process are provided, along with comparison of measurement results with simulations. The system demonstrates a constant-force of 79 +/- 2 mu N at an operating voltage of 25 V, with the possibility of adjusting the constant-force by changing the voltage.
Article
Automation & Control Systems
Yongjiang Chen, Jianghai Zhao, Yujie Jin
Summary: This paper presents a rational Bezier-based state fitting method (BSFM) for calibrating the nonlinear characteristics of low-cost pneumatic constant force systems. Compared to the commonly used polynomial-based methods, the BSFM achieves better calibration results and maintains a balance between simplicity and precision.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Yaowei Liu, Lu Li, Huiying Gong, Ke Li, Qili Zhao, Ruixin Li, Linkun Zhang, Xin Zhao, Mingzhu Sun
Summary: This study aimed to develop a robotic system for automated cell aspiration and in situ micropipette cleaning to measure cellular shear adhesion force. The system achieved automation through cell selection based on image texture analysis, contact detection based on motion history image analysis, and cell aspiration state detection based on sub-pixel image registration. Experimental results showed that pancreatic cancer cells possessed higher shear adhesion force than osteoblasts and osteoclasts, with a significant difference between osteoblasts and osteoclasts.
IEEE SENSORS JOURNAL
(2023)
Article
Engineering, Aerospace
XueAi Li, Kui Sun, Hong Liu
Summary: In this paper, a modified constant-torque spring hinge (MCTSH) is proposed for aerospace applications, which has a compact structure, low friction, and wide-range output torque. By introducing a novel torque control method and synchronous deployment technique, the design process is simplified, and the performance is verified through simulations and experiments.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Cell Biology
Andrew D. Stephens, Chloe E. Snider, Kerry Bloom
Article
Cell Biology
Andrew D. Stephens, Edward J. Banigan, Stephen A. Adam, Robert D. Goldman, John F. Marko
MOLECULAR BIOLOGY OF THE CELL
(2017)
Review
Cell Biology
Andrew D. Stephens, Edward J. Banigan, John F. Marko
Review
Cell Biology
Andrew D. Stephens, Edward J. Banigan, John F. Marko
Article
Cell Biology
Andrew D. Stephens, Chloe E. Snider, Julian Haase, Rachel A. Haggerty, Paula A. Vasquez, M. Gregory Forest, Kerry Bloom
JOURNAL OF CELL BIOLOGY
(2013)
Article
Cell Biology
Andrew D. Stephens, Rachel A. Haggerty, Paula A. Vasquez, Leandra Vicci, Chloe E. Snider, Fu Shi, Cory Quammen, Christopher Mullins, Julian Haase, Russell M. Taylor, Jolien S. Verdaasdonk, Michael R. Falvo, Yuan Jin, M. Gregory Forest, Kerry Bloom
JOURNAL OF CELL BIOLOGY
(2013)
Article
Cell Biology
Chloe E. Snider, Andrew D. Stephens, Jacob G. Kirkland, Omar Hamdani, Rohinton T. Kamakaka, Kerry Bloom
JOURNAL OF CELL BIOLOGY
(2014)
Review
Cell Biology
Jolien S. Verdaasdonk, Andrew D. Stephens, Julian Haase, Kerry Bloom
JOURNAL OF CELLULAR PHYSIOLOGY
(2014)
Article
Multidisciplinary Sciences
Scott Gladstein, Luay M. Almassalha, Lusik Cherkezyan, John E. Chandler, Adam Eshein, Aya Eid, Di Zhang, Wenli Wu, Greta M. Bauer, Andrew D. Stephens, Simona Morochnik, Hariharan Subramanian, John F. Marko, Guillermo A. Ameer, Igal Szleifer, Vadim Backman
NATURE COMMUNICATIONS
(2019)
Review
Cell Biology
Andrew D. Stephens, Edward J. Banigan, John F. Marko
CURRENT OPINION IN CELL BIOLOGY
(2019)
Review
Cell Biology
Chad M. Hobson, Andrew D. Stephens
Article
Cell Biology
Isabel K. Berg, Marilena L. Currey, Sarthak Gupta, Yasmin Berrada, Bao Nguyen, Mai Pho, Alison E. Patteson, J. M. Schwarz, Edward J. Banigan, Andrew D. Stephens
Summary: Chromatin plays a crucial role in maintaining nuclear shape and function, but transcription activity can also affect nuclear shape through its impact on chromatin structure and dynamics. In this study, we found that transcription inhibition suppresses nuclear blebbing and rupture, independent of chromatin rigidity.
JOURNAL OF CELL SCIENCE
(2023)
Meeting Abstract
Cell Biology
A. D. Stephens, P. Z. Liu, E. J. Banigan, L. M. Almassalha, V. Backman, S. A. Adam, R. D. Goldman, J. F. Marko
MOLECULAR BIOLOGY OF THE CELL
(2017)
Article
Biophysics
Edward J. Banigan, Andrew D. Stephens, John F. Marko
BIOPHYSICAL JOURNAL
(2017)