Search results for "Microscopy"

Randomized controlled trial comparing embryo culture in two incubator systems: G185 K-System versus EmbryoScope

2017

Objective To study whether the closed culture system, as compared with a benchtop incubator with similar culture conditions, has a positive impact on intracytoplasmic sperm injection (ICSI) outcomes. Design Randomized controlled trial. Setting University hospital. Patient(s) A total of 386 patients undergoing ICSI cycles with at least six mature oocytes were randomized. Intervention(s) Of these patients, 195 were assigned to the group with culture in a time-lapse imaging (TLI) system (EmbryoScope) and 191 to the group with culture in the G185 K-System (G185). Main Outcome Measure(s) Rate of implantation (primary endpoint) and embryo morphology grade. Result(s) No significant differences wer…

2018

Abstract Purpose To report on a case of recurrence of paraproteinemic keratopathy (PPK) associated with monoclonal gammopathy after bilateral penetrating keratoplasty. Observations Penetrating keratoplasty was performed on both eyes of a 45-year-old man due to bilateral progressive corneal stromal clouding. Recurrence of the corneal stromal opacities accompanied by a decrease in visual acuity was observed on slit-lamp examination already two years after penetrating keratoplasty. Confocal laser scanning microscopy (CLSM) of the corneal grafts performed three years after penetrating keratoplasty showed bilateral morphological changes identical to that found in the patient's corneas prior to p…

Atherothrombosis and Thromboembolism: Position Paper from the Second Maastricht Consensus Conference on Thrombosis

2018

AbstractAtherothrombosis is a leading cause of cardiovascular mortality and long-term morbidity. Platelets and coagulation proteases, interacting with circulating cells and in different vascular beds, modify several complex pathologies including atherosclerosis. In the second Maastricht Consensus Conference on Thrombosis, this theme was addressed by diverse scientists from bench to bedside. All presentations were discussed with audience members and the results of these discussions were incorporated in the final document that presents a state-of-the-art reflection of expert opinions and consensus recommendations regarding the following five topics: 1. Risk factors, biomarkers and plaque inst…

Viral highway to nucleus exposed by image correlation analyses.

2018

AbstractParvoviral genome translocation from the plasma membrane into the nucleus is a coordinated multistep process mediated by capsid proteins. We used fast confocal microscopy line scan imaging combined with image correlation methods including auto-, pair- and cross-correlation, and number and brightness analysis, to study the parvovirus entry pathway at the single-particle level in living cells. Our results show that the endosome-associated movement of virus particles fluctuates from fast to slow. Fast transit of single cytoplasmic capsids to the nuclear envelope is followed by slow movement of capsids and fast diffusion of capsid fragments in the nucleoplasm. The unique combination of …

ODELAY: A Large-scale Method for Multi-parameter Quantification of Yeast Growth

2017

Growth phenotypes of microorganisms are a strong indicator of their underlying genetic fitness and can be segregated into 3 growth regimes: lag-phase, log-phase, and stationary-phase. Each growth phase can reveal different aspects of fitness that are related to various environmental and genetic conditions. High-resolution and quantitative measurements of all 3 phases of growth are generally difficult to obtain. Here we present a detailed method to characterize all 3 growth phases on solid media using an assay called One-cell Doubling Evaluation of Living Arrays of Yeast (ODELAY). ODELAY quantifies growth phenotypes of individual cells growing into colonies on solid media using time-lapse mi…

Lack of evidence of mimivirus replication in human PBMCs

2018

The Acanthamoeba polyphaga mimivirus (APMV) was first isolated during a pneumonia outbreak in Bradford, England, and since its discovery many research groups devoted efforts to understand whether this virus could be associated to human diseases, in particular clinical signs and symptoms of pneumonia. In 2013, we observed cytopathic effect in amoebas (rounding and lysis) inoculated with APMV inoculated PBMCs (peripheral blood mononuclear cell) extracts, and at that point we interpreted those results as mimivirus replication in human PBMCs. Based on these results we decided to further investigate APMV replication in human PBMCs, by transmission electron microscopy (TEM) and qPCR. No viral fac…

Bacteriophage imaging : past, present and future

2018

The visualization of viral particles only became possible after the advent of the electron microscope. The first bacteriophage images were published in 1940 and were soon followed by many other publications that helped to elucidate the structure of the particles and their interaction with the bacterial hosts. As sample preparation improved and new technologies were developed, phage imaging became important approach to morphologically classify these viruses and helped to understand its importance in the biosphere. In this review we discuss the main milestones in phage imaging, how it affected our knowledge on these viruses and recent developments in the field. peerReviewed

Membrane-Associated Enteroviruses Undergo Intercellular Transmission as Pools of Sibling Viral Genomes

2019

Summary Some viruses are released from cells as pools of membrane-associated virions. By increasing the multiplicity of infection (MOI), this type of collective dispersal could favor viral cooperation, but also the emergence of cheater-like viruses such as defective interfering particles. To better understand this process, we examined the genetic diversity of membrane-associated coxsackievirus infectious units. We find that infected cells release membranous structures (including vesicles) that contain 8–21 infectious particles on average. However, in most cases (62%–93%), these structures do not promote the co-transmission of different viral genetic variants present in a cell. Furthermore, …

Imaging Noncanonical Autophagy and LC3-Associated Phagocytosis in Cultured Cells

2019

International audience; Monitoring of ATG8 proteins by western blotting and immunofluorescence microscopy are the most common methods to monitor the autophagy pathway. However, it has recently been shown that ATG8 proteins can be lipidated to non-autophagosome, single-membrane compartments through a noncanonical autophagy pathway. This is commonly found to occur during macro-endocytic processes such as phagocytosis, where it has been termed LC3-associated phagocytosis, and upon lysosomotropic drug treatment. Therefore, care is required when interpreting data based on ATG8 in order to conclude whether a signal relates to the canonical or noncanonical pathway. Here we provide methods to monit…

Application of high-content screening for the study of hepatotoxicity: Focus on food toxicology

2020

Safety evaluation of thousands of chemicals that are directly added to or come in contact with food is needed. Due to the central role of the liver in intermediary and energy metabolism and in the biotransformation of foreign compounds, the hepatotoxicity assessment is essential. New approach methodologies have been proposed for the safety evaluation of compounds with the idea of rapidly gaining insight into effects on biochemical mechanisms and cellular processes and screening large number of compounds. In this sense, high-content screening (HCS) is the application of automated microscopy and image analysis for better understanding of complex biological functions and mechanisms of toxicity…