China
Africa
Explore chapters and articles related to this topic
Non-VLPs
Published in Paul Pumpens, Single-Stranded RNA Phages, 2020
Martins et al. (2018) engineered a software, namely, SCIP, to analyze multimodal, multiprocess, time-lapse microscopy morphological and functional images. The SCIP software was capable of automatic and manually corrected segmentation of cells and lineages, automatic alignment of different microscopy channels, and was able to detect, count, and characterize fluorescent spots, such as RNA tagged by the MS2-GFP imaging. The RNA2DMut web tool was generated for the design and analysis of RNA structure mutations in order to find the optimal MS2 aptamer sequences (Moss 2018). The MS2 coat-RNA operator complex measurements were used by the development of a novel test for the RNA-protein binding affinity prediction (Kappel et al. 2019). In addition, the fully automated RiboLogic method was used to design riboswitches that could modulate their affinity to the MS2 coat protein upon binding of flavin mononucleotide, tryptophan, theophylline, and microRNA miR-208a (Wu MJ et al. 2019).
New guidelines for setting up an assisted reproduction technology laboratory
Published in David K. Gardner, Ariel Weissman, Colin M. Howles, Zeev Shoham, Textbook of Assisted Reproductive Techniques, 2017
Jacques Cohen, Mina Alikani, Antonia Gilligan, Tim Schimmel
Development of new time-lapse microscopy technologies has made continuous and uninterrupted monitoring of embryo development a reality. This is an invaluable teaching and learning tool. However, equipment costs are high and, for many laboratories, prohibitive. Equipment for time-lapse technology can be sizable and may require separate consideration in terms of lab design and bench space.
Cell death after irradiation: How, when and why cells die
Published in Michael C. Joiner, Albert J. van der Kogel, Basic Clinical Radiobiology, 2018
Time-lapse microscopy studies have demonstrated that in cells which experience mitotic catastrophe, both the timing and nature of cell death are highly variable (Figure 3.6) (5). As discussed earlier, a surviving cell is considered as one that can proliferate indefinitely. In tissue culture, this is quantified by the ability to form a colony of a certain size after irradiation (usually 50 cells). Conversely, cell death in this context means that eventually all progeny of an irradiated cell will die. An irradiated cell that is destined to die (not produce a colony) may, however, still proceed through mitosis multiple times. The resulting daughter cells can die at very different times after irradiation. For example, following the first mitosis, one of the cells may die and the other may proceed through DNA replication and mitosis to produce two more cells. Eventually these cells will die too, although they may or may not attempt mitosis multiple times. Furthermore, the type of cell death that each daughter cell undergoes can be different. Consequently, a single irradiated cell can actually die through multiple modes of cell death. A similar situation also exists for irradiated cells that are destined to survive. These cells may also produce daughter cells with different survival potential. One daughter may die, while the other continues to proliferate and thus confers the status of ‘survived’ on the initially irradiated cell. Consequently, irradiated cells that die following cell division produce a pedigree of cells with different types that can only be tracked by time-lapse microscopy (6). Examples of cells destined for survival or death are shown in Figure 3.6. This figure underscores the many problems associated with trying to quantify or ascribe a particular form of cell death after irradiation and the importance of the clonogenic survival assay for determining the ultimate response of individually irradiated cells.
The relationship between good quality embryo rates and IVF outcomes/embryo transfer policies in extended embryo culture
Published in Journal of Obstetrics and Gynaecology, 2022
Ayten Türkkanı, Cemile Merve Seymen, İnci Kahyaoğlu, İskender Kaplanoğlu, A. Şebnem İlhan, Çiğdem Elmas, Serdar Dilbaz
Novel techniques have been developed, since the morphological evaluation of the embryo is considered to be insufficient in the estimation of the quality of the embryo. These techniques particularly focus on developing new non-invasive methods using molecular approaches based on small non-coding RNA, including proteomics, metabolomics, and in culture media microRNA. Furthermore, time-lapse microscopy (TLM) is an exciting new technology with great potential to improve embryo selection in the embryology laboratory. Evaluation of embryos according to these non-invasive morphokinetic features has provided a new tool in the estimation of embryo development and implantation potential. A number of authors have analysed the timing of each early event during the development of good-quality blastocysts, depending on whether they were implanted or not. Finally, few parameters, such as time to syngamy (tPNf), times to 2 (t2), 3 (t3), 5 (t5) and eight (t8) cells, t2-tPNF, t5–t2 or cc3 (t5–t3), are significantly different between implanted and non-implanted blastocysts (Chamayou et al. 2013; Desai et al. 2014). Consequently, new studies are needed to determine which morphokinetic criteria are the best embryo selection criteria (Motato et al. 2016; Zaninovic et al. 2017). Since static and morphokinetic parameters alone are not sufficient in the selection of the euploid embryo, PGT-A, which is an invasive procedure, has become a method used to select the euploid embryo these days. It has been shown that using static and morphokinetic methods in embryo selection can reduce the number of embryos applied with PGT-A (Minasi et al. 2016).
Moving beyond size and phosphatidylserine exposure: evidence for a diversity of apoptotic cell-derived extracellular vesicles in vitro
Published in Journal of Extracellular Vesicles, 2019
Ivan K. H. Poon, Michael A. F. Parkes, Lanzhou Jiang, Georgia K. Atkin-Smith, Rochelle Tixeira, Christopher D. Gregory, Dilara C. Ozkocak, Stephanie F. Rutter, Sarah Caruso, Jascinta P. Santavanond, Stephanie Paone, Bo Shi, Amy L. Hodge, Mark D. Hulett, Jenny D. Y. Chow, Thanh Kha Phan, Amy A. Baxter
Samples in 1% BSA/1× A5 binding buffer/RPMI were stained with A5-FITC or A5-APC and seeded into wells of a Lab-Tek II 8-well chamber slide (Nunc). Live microscopy was performed on either a Zeiss Spinning disk, LSM 780 or LSM 800 confocal microscope (Zeiss) at 37°C in a humidified atmosphere containing 5% CO2, and using a 63× oil immersion objective. For experiments involving phosphatidylserine (PtdSer) detection on ApoBDs, images were collected over approximately 1 h. For experiments in which non-UV-irradiated cells and ApoBD stability were monitored, time-lapse microscopy was performed over 4 to 6 h. All images were analysed using ZEN Lite 2.3 program (Zeiss).
Carbonic Anhydrase Inhibitors suppress platelet procoagulant responses and in vivo thrombosis
Published in Platelets, 2020
Ejaife O. Agbani, Xiaojuan Zhao, Christopher M. Williams, Riyaad Aungraheeta, Ingeborg Hers, Erik R. Swenson, Alastair W. Poole
Mice were anaesthetised with ketamine 100 mg/kg (Vetalar V, Pfizer) and 10 mg/kg xylazine (Rompun, Bayer). Platelets were labeled by intravenous administration of 100 mg/kg Dylight-488 conjugated anti-GPIbβ antibody, 10 min prior to induction of thrombosis. Right carotid arteries were exposed and 2 × 1 mm 12% ferric chloride-soaked filter paper was placed on the arterial adventitia for 3 min. Time-lapse microscopy of the injury site for 20 min was performed and images processed using ImageJ. Background fluorescence values measured upstream of the injury site were subtracted from thrombus-specific fluorescence and data expressed as integrated densities.