Breaking News
August 14, 2018 - American Heart Association Urges Screen Time Limits for Youth
August 14, 2018 - Brief interventions during routine care reduce alcohol use among men with HIV
August 14, 2018 - New genome analysis could identify people at higher risk of common deadly diseases
August 14, 2018 - NIH grant for Mount Sinai to study use of inhaled corticosteroids for treatment of sickle cell disease
August 14, 2018 - Daicel supplies free nanodiamond samples to international researchers
August 14, 2018 - Switching anti-psychotic drugs in first-episode schizophrenia patients does not improve clinical outcomes
August 14, 2018 - Study to examine whether modulating gut bacteria can improve cardiac function in heart failure patients
August 14, 2018 - One out of two children not getting enough nutrients needed for their health
August 14, 2018 - Mono-antiplatelet therapy after aortic heart valve replacements may work as well as two drugs
August 14, 2018 - Aid-in-dying patient chooses his last day
August 14, 2018 - Exercise Really Can Chase Away the Blues, to a Point
August 14, 2018 - Surgical mesh implants may cause autoimmune disorders
August 14, 2018 - Researchers develop revolutionary zebrafish model to gain more insight into bone diseases
August 14, 2018 - Researchers discover secret communication hotline between breast cancers and normal cells
August 14, 2018 - Study examines how a person adapts to visual field loss after stroke
August 14, 2018 - Researchers show how specialized nucleic acid-based nanostructures could help target cancer cells
August 14, 2018 - Reducing opioid prescriptions for one operation can also spill over to other procedures
August 14, 2018 - E-cigarettes not so safe but still better than cigarettes
August 14, 2018 - Researchers find link between common ‘harmless’ virus and cardiovascular damage
August 14, 2018 - Initiation of PIMs associated with higher risk of fracture-specific hospitalizations and mortality
August 14, 2018 - Genetically modified mosquitoes and special bed nets help tackle deadly diseases
August 14, 2018 - Advances in treating hep C lead to new option for transplant patients
August 14, 2018 - Study finds quality of doctor-patient discussions about lung cancer screening to be ‘poor’
August 14, 2018 - MSU researchers uncover the effects of aging on regenerative ability of kidneys
August 14, 2018 - Better conditioning, throwing mechanics can help reduce elbow injuries in young baseball pitchers
August 14, 2018 - Brain game doesn’t offer brain gain
August 14, 2018 - Reproductive choices facing women with disabilities require careful consideration
August 14, 2018 - Scientists pinpoint the cause of a rare childhood seizure disorder
August 14, 2018 - Lumpectomy plus radiation associated with reduced risk of breast cancer death, study finds
August 14, 2018 - UAB study shows how ion channel differentiates newborn and mature neurons in the brain
August 14, 2018 - Experts highlight key knowledge gaps that need to be addressed in Ebola vaccine research
August 14, 2018 - Discovery could lead to new drugs against infection and inflammation
August 14, 2018 - Infection Prevention Differs Between Small, Large Hospitals
August 14, 2018 - Mom still matters—In study, young adults tended to prioritize parents over friends
August 14, 2018 - Deep brain stimulation might benefit those with severe alcoholism, preliminary studies show
August 14, 2018 - Study finds increased rate of repeat pregnancies in women with intellectual and developmental disabilities
August 14, 2018 - Lighter sedation fails to reduce risk of postoperative delirium in older patients
August 13, 2018 - Asking better questions about person’s memory could improve doctors’ understanding of patients
August 13, 2018 - U.S. Trauma Doctors Push for Stricter Gun Controls
August 13, 2018 - Asthma and flu: a double whammy
August 13, 2018 - 5 Questions: Donna Zulman on engaging high-need patients in intensive outpatient programs | News Center
August 13, 2018 - Behavioral Nudges Lead to Drop in Prescriptions of Potent Antipsychotic
August 13, 2018 - Potential New Class of Drugs May Reduce Cardiovascular Risk by Targeting Gut Microbes
August 13, 2018 - How to get your kids to eat better
August 13, 2018 - The importance of hearing your patients
August 13, 2018 - Transmission of F. tularensis unlikely to happen through the food chain
August 13, 2018 - Researchers discover epigenetic mechanism underlying ischemic cardiomyopathy
August 13, 2018 - Adolescent health programs receive only a tiny share of international aid, finds research
August 13, 2018 - Fracture risk increases by 30% after gastric bypass, study shows
August 13, 2018 - Quality-improvement project to standardize feeding practices helps micro preemies gain weight
August 13, 2018 - Long-term cannabinoid exposure impairs memory, study shows
August 13, 2018 - New intervention to reduce risk of HIV in young transgender women
August 13, 2018 - Japan human trial tests iPS cell treatment for Parkinson’s
August 13, 2018 - Altered nitrogen metabolism may contribute to emergence of new cancer mutations
August 13, 2018 - Cycling provides greatest health benefits, study finds
August 13, 2018 - Scientists discover biomarker for kidney cancer
August 13, 2018 - New test predicts the risk of serious disease before symptoms appear
August 13, 2018 - Cianna Medical receives FDA 510(k) clearance to extend indication of SCOUT reflector for use in soft tissue localization
August 13, 2018 - Ground-breaking discovery offers new hope for treatment of Alzheimer’s, other neurological diseases
August 13, 2018 - Medical nutrition therapy provided by RDNs benefits patients with chronic kidney disease
August 13, 2018 - Prenatal Tdap vaccination not linked with increased risk of autism in children, study shows
August 13, 2018 - One-Third of Canadian Patients Get Hip Fx Repair Within 24 Hours
August 13, 2018 - ANA (Antinuclear Antibody) Test: MedlinePlus Lab Test Information
August 13, 2018 - Traffic jams in the brain
August 13, 2018 - NIH awards $6.5 million to establish multi-institution biomedical technology resource center
August 13, 2018 - New marker in the blood could help predict person’s risk of developing kidney cancer
August 13, 2018 - New biomarker may provide clues to create diagnostic tool for hypoglycemia-associated autonomic failure
August 13, 2018 - Oxidative Stress Hampers Blood Vessel Dilation in Men
August 13, 2018 - Parents’ Religious Beliefs May Affect Kids’ Suicide Risk: Study
August 13, 2018 - Measure of belly fat in older adults is linked with cognitive impairment
August 13, 2018 - FDA permits marketing of first mobile medical app for contraceptive use to prevent pregnancy
August 13, 2018 - NUS scientists develop new technology to customize optimal drug ‘cocktail’ for myeloma patients
August 13, 2018 - Disordered eating behaviors up for overweight young adults
August 13, 2018 - Connection between Alzheimer’s disease and degenerative eye diseases
August 13, 2018 - Employer expectation of checking email during nonwork hours affects health of workers and families
August 13, 2018 - Rotavirus vaccination reduces infant diarrhea deaths by 34% in rural Malawi
August 13, 2018 - Approval of drug derived from cannabis not necessarily a win for weed
August 13, 2018 - Study shows COPD risk in women with asthma can be reduced
August 13, 2018 - FIND and genedrive announce study agreement to evaluate HCV ID Kit
August 13, 2018 - One in two people putting their eye health at risk during summer, says eye research charity
Scientists develop unique technique to map elasticity of cell components

Scientists develop unique technique to map elasticity of cell components

image_pdfDownload PDFimage_print

Scientists at Université de Montréal have developed a unique technique to map, on a scale of milliseconds, the elasticity of the components inside a cell.

Cells quake. In somewhat the same way that seismologists use the vibrations of planet Earth to characterize its deep structure, scientists have discovered a way to use vibrations within cells to identify their mechanical properties. Thus was born the field of cell seismology.

“We developed a unique technique to map, on a scale of milliseconds, the elasticity of the components inside a cell,” said Guy Cloutier, a researcher at the University of Montreal Hospital Research Centre (CRCHUM) and professor at Université de Montréal. “This opens up a whole new field of research in mechanobiology to study the dynamics of displacements inside cells and understand the impact of these forces on diseases and treatments.”

The technology, called “cell quake elastography”, is presented in an article published today in the Proceedings of the National Academy of Sciences (PNAS).

Elasticity is a fundamental property of cells, related to the anatomy, function and pathological state of cells and tissues. A cancerous tumour becomes rigid. Atherosclerosis and vascular aneurysms start with a loss of elasticity in the cells and arteries. Endothelial cells release transmitters that cause the vasoconstriction or vasodilation of blood vessels, depending on the mechanical shear conditions associated with vessel flow and geometry.

“Until now, it has been difficult to measure the mechanical changes that continuously occur in cells,” explained Pol Grasland-Mongrain, a post-doctoral trainee in Guy Cloutier’s laboratory and the principal author of the study. “With current techniques, based on cell deformation, atomic force microscopy and Brillouin scattering, it can take several dozen minutes to measure elasticity. For certain applications, this is much too slow because thousands of events can occur in a cell, such as ion transfers, neuron stimulations and cell death. These phenomena would be easier to track if we were able to measure the mechanical properties of cells very quickly.”

With simple equipment consisting of a standard microscope, micropipettes and a high-speed camera, the researchers developed a revolutionary method of observing, in real time, the displacements and forces present in mouse oocytes. According to Greg FitzHarris, a researcher at the CRCHUM, Université de Montréal professor and one of the project’s collaborators, “with this new cellular imaging method, we will be able to investigate new mechanisms involved in cell division during embryo formation”.

“In the beginning, we had no idea of the level of spatial resolution that we could hope for, which is what gave us the idea of using mouse oocytes,” added Guy Cloutier. “These cells are large – about 80 microns in diameter – and are therefore easier to view with our new microelastography technique. In our experiments, we were able to observe mechanical vibrations in the cell lasting less than a thousandth of a second, thanks to the camera used, which can capture 200,000 frames per second.” By way of comparison, a movie usually has only 25 frames per second.  

With the images captured, these vibrations can be measured using displacement-tracking algorithms. But how can a map of intracellular elasticity be reconstructed from these vibrations? The answer: By using a noise correlation technique, an approach developed by seismologists when they measure the vibrations produced by earthquakes to determine the composition of subterranean rocks.

“We used this same principle to explore the internal structure of the cell from a mechanical point of view, applying shear wave elastography at the micrometer scale,” said Stefan Catheline, a physicist at the Institut national de la santé et de la recherche médicale (INSERM) and researcher at the University of Lyon in France. “A wave is sent into the cell at a speed proportional to the elasticity of the components that it meets, such as the cytoplasm, nucleus or the other cell components. Elasticity is measured by evaluating the speed of the vibrations in time and space.”

Pol Grasland-Mongrain explained the process he went through to make his observations: “Using a micropipette piezoelectric actuator, we induced high-frequency vibrations (15,000 cycles per second) into live mouse oocytes. With the images captured by the camera, we measured the vibrations inside the cell, using an optical flow algorithm developed initially for ultrasound applications. Next, the noise correlation algorithm allowed us to map the elasticity of the entire cell. Thus, in this study, we were able to show, among other things, that a significant reduction in mouse oocyte elasticity occurred when the oocytes treated with cytochalasin, a substance known to disrupt their cytoskeleton.”

This innovative cell elasticity mapping technology opens the door to many practical applications in biology and medicine, whether for cancer, pathogen-induced infection, scarring or tissue engineering. “Now that we’ve shown the feasibility of the technology, we can fine-tune the method and develop collaborations with experts in cellular and molecular biology, physiology and mechanobiology to explore the incredible potential of this field of research,” Guy Cloutier concluded.

Source:

http://nouvelles.umontreal.ca/en/article/2018/01/16/cellular-seismology-putting-vibrations-on-the-map/

Tagged with:

About author

Related Articles