Publications associées à Digital holographic microscopy applied to life sciences

In vitro-transfusional model for red-blood-cell study: the advantage of lowering hematocrit

Gerardo Turcatti, Michel Prudent, Manon Sandra Bardyn, David Crettaz

Background - Thequalityof red blood cells (RBCs) stored in red cell concentrates (RCCs) is influenced by processing, storage and donor characteristics, and can have a clinical impact on transfused patients. To evaluate RBC properties and their potential im ...

Simtipro Srl2023

Automated Dual-Mode Cell Monitoring To Simultaneously Explore Calcium Dynamics and Contraction-Relaxation Kinetics within Drug-Treated Stem Cell-Derived Cardiomyocytes

Gerardo Turcatti, Pierre Marquet, Benjamin Rappaz, Bokyoung Kim

This manuscript proposes a new dual-mode cell imaging system for studying the relationships between calcium dynamics and the contractility process of cardiomyocytes derived from human-induced pluripotent stem cells. Practically, this dual-mode cell imaging ...

AMER CHEMICAL SOC2023

New approaches to uncover the minimally functional hematopoietic niche using the adipocytic differentiation axis: pharmacological modulation and adrenal niche induction

Frédérica Schyrr

Hematopoietic Stem and Progenitor Cells (HSPCs) reside in their niche, a structure that regulates the balance of cellular quiescence, self-renewal and commitment towards differentiated cells. This highly plastic niche is formed by several cellular players, ...

EPFL2022

Image- and Fluorescence-Based Test Shows Oxidant-Dependent Damages in Red Blood Cells and Enables Screening of Potential Protective Molecules

Gerardo Turcatti, Michel Prudent, Benjamin Rappaz, Manon Sandra Bardyn, David Crettaz

An increase of oxygen saturation within blood bags and metabolic dysregulation occur during storage of red blood cells (RBCs). It leads to the gradual exhaustion of RBC antioxidant protective system and, consequently, to a deleterious state of oxidative st ...

2021

High-throughput and adaptive super-resolution fluorescence microscopy of organelles

Dora Mahecic

Fluorescence super-resolution microscopy has allowed unprecedented insight into the workings of biological systems below the diffraction limit of light. Over the past decade, it has overcome several challenges to deliver 3D, multi-color and faster imaging ...

EPFL2020

Near-field phase profile and far-field contrast modulation for micro-lens arrays at the refraction limit

Toralf Scharf, Maryam Yousefi, Daniel Necesal

We investigate the far-field pattern generation for a micro-lens array (MLA) illuminated under different conditions. Plane wave and Gaussian beam illumination are considered for an MLA with a small diameter of 27 microns and 30 microns period. At these dim ...

2020

Correction of spherical surface measurements by confocal microscopy

Wilfried Noell, Toralf Scharf, Jeremy Béguelin

Refractive microlenses are nowadays widely used in optical systems. Characterizing their surface is essential to ensure their quality and to optimize their fabrication process. This is realized by optical surface profilers thanks to their vertical resoluti ...

2020

Photoactivatable Silicon Rhodamines for Super-Resolution Microscopy

Michelle Susanne Frei

Fluorescence microscopy is the method of choice to monitor dynamic processes in living cells due to its non-invasive nature. A variety of different fluorophores and labeling systems are currently used to selectively visualise structures or biomolecules of ...

EPFL2020

Metabolic and microenvironmental strategies to accelerate hematopoietic recovery post-aplasia

Vasco Ledebur de Antas de Campos

The procedure-associated mortality rate of bone marrow transplantations (BMT) remains close to 25%. The BMT is therefore only indicated for life-threatening diseases, with no replacement of this technology to be expected in the foreseeable future. Modest i ...

EPFL2019

Image-Based Marker-Free Screening of GABA(A) Agonists, Antagonists, and Modulators

Gerardo Turcatti, Pierre Marquet, Damiano Banfi, Pascal Jourdain, Benjamin Rappaz, Fabien Kuttler

The ionotropic GABA(A) receptors represent the main target for different groups of widely used drugs having hypnotic and anxiolytic effects. So far, most approaches used to assess GABA activity involve invasive low -throughput electrophysiological techniqu ...

2019

Waveguide platform and methods for super-resolution fluorescence microscopy of sub-cellular structures

Anna Archetti

Super-resolution fluorescence microscopy is widespread, owing to its demonstrated ability to resolve dynamical processes within cells and to identify the structure and position of specific proteins in the interior of protein complexes. Nowadays, subcellula ...

EPFL2019

Compact lensless digital holography

Manon Rostykus

Microscopy is of high interest for biology since it allows imaging features that are too small to be seen with naked eyes. However, cells are mostly transparent to visible and infrared light which makes it difficult to see with a traditional microscope. To ...

EPFL2018

Quantification of stored red blood cell fluctuations by time-lapse holographic cell imaging

Gerardo Turcatti, Pierre Marquet, Michel Prudent, Benjamin Rappaz, Manon Sandra Bardyn

We propose methods to quantitatively calculate the fluctuation rate of red blood cells with nanometric axial and millisecond temporal sensitivity at the single-cell level by using time-lapse holographic cell imaging. For this quantitative analysis, cell me ...

2018

Identification of Oxidative Stress in Red Blood Cells with Nanoscale Chemical Resolution by Infrared Nanospectroscopy

Giovanni Dietler, Giovanni Longo, Francesco Simone Ruggeri

During their lifespan, Red blood cells (RBC), due to their inability to self-replicate, undergo an ageing degradation phenomenon. This pathway, both in vitro and in vivo, consists of a series of chemical and morphological modifications, which include devia ...

2018

Coherent imaging from bacteria to multicellular organisms

Séverine Coquoz

Structural and functional imaging of cells, tissues and organisms is crucial for understanding biomedical processes. Fluorescence microscopy is an established tool and has contributed to many discoveries in the life sciences. This technique provides molecu ...

EPFL2017

Microscopy and digital light shaping through optical fibers

Damien Claude-Marie Loterie

Microscopy is an essential tool in medicine and biomedical research. Traditional microscopes rely on bulky optics, complicating their usage when studying live animal tissues. In addition, light cannot penetrate very far in most biological tissues due to sc ...

EPFL2017

Automated tracking of temporal displacements of a red blood cell obtained by time-lapse digital holographic microscopy

Benjamin Rappaz

Red blood cell (RBC) phase images that are numerically reconstructed by digital holographic microscopy (DHM) can describe the cell structure and dynamics information beneficial for a quantitative analysis of RBCs. However, RBCs investigated with time-lapse ...

Optical Soc Amer2016

Compressed imaging by sparse random convolution

Theo Lasser, Antonio Lopez, Aurélien Bourquard

The theory of compressed sensing (CS) shows that signals can be acquired at sub-Nyquist rates if they are sufficiently sparse or compressible. Since many images bear this property, several acquisition models have been proposed for optical CS. An interestin ...

Optical Society of America2016

Automated multi-parameter measurement of cardiomyocytes dynamics with digital holographic microscopy

Gerardo Turcatti, Pierre Marquet, Benjamin Rappaz

Compounds tested during drug development may have adverse effects on the heart; therefore all new chemical entities have to undergo extensive preclinical assessment for cardiac liability. Conventional intensity-based imaging techniques are not robust enoug ...

Optical Society of America2015

Influence of the glycocalyx and plasma membrane composition on amphiphilic gold nanoparticle association with erythrocytes

Francesco Stellacci, Randy Patrick Carney, Paulo Henrique Jacob Silva, Ye Yang, Ahmet Bekdemir

Erythrocytes are attractive as potential cell-based drug carriers because of their abundance and long life-span in vivo. Existing methods for loading drug cargos into erythrocytes include hypotonic treatments, electroporation, and covalent attachment onto ...

Royal Society of Chemistry2015