Approaches to imaging fast biological events

The next talk in the Cambridge Advanced Imaging Lecture series will be held at CRUK CI and will be given by Michael Shaw and Vikas Trivedi. The abstracts for the talks are detailed below. Please forward to anyone you think may be interested.The next talk in the Cambridge Advanced Imaging Lecture series will be held at CRUK CI and will be given by Michael Shaw and Vikas Trivedi. The abstracts for the talks are detailed below. Please forward to anyone you think may be interested.Theme of talk: Approaches to imaging fast biological eventsDate of talk: 5th DecemberTime: 4pm-5pmLocation of talk: CRUK CI - Lecture theatreSpeaker 1: Dr Michael Shaw (NPL Senior Research Scientist/ UCL Senior Research Associate) Title: High speed 3D imaging using light field microscopy for neurobiological and behavioural studies of C. elegans Abstract: The model organism C. elegans is used in a range of fundamental studies of physiology and development as well as drug screening. However, to fully capture the behaviour and neurological response of the organism requires high speed volumetric imaging which is impossible using most conventional microscopy techniques. In this talk I will describe how we have used light field microscopy, in which multiple perspective views of the organism are captured simultaneously using a microlens array placed at the native image plane of a conventional microscope, to measure neuronal activity and quantify the locomotion of C. elegans in 3D. I will discuss some of the strengths and limitations of the technique and discuss how it is being used at UCL to investigate the process of mechanosensation.Speaker 2: Dr Vikas Trivedi (Herchel Smith Postdoctoral Fellow, Department of Genetics, University of Cambridge)  Title: 2-photon light sheet imaging of zebrafish heart Abstract: Single Plane Illumination Microscopy (SPIM) has emerged as a powerful tool to capture fast dynamics of biological tissue in 4D (space + time). However fast volumetric imaging of beating heart at sub-cellular resolution in developing embryos has remained a challenge. In the case of zebrafish by 4 days post fertilization (dpf), heart is a 200um scale structure, moving quasi-periodically in 3D at a few Hertz frequency, with movements >100um, which presents a major roadblock for 4D imaging. Further as the optical properties of surrounding tissues change over time, especially with development of brachial arches, imaging the heart, placed deep in the chest cavity, presents further challenges. We therefore developed a bidirectional 2-photon illumination SPIM that provides deep and fast optical sectioning. Further we made straightforward hardware modifications to the conventional SPIM set up by introducing an additional imaging path. This allows accurate determination of the spatio-temporal phase of the moving heart for imaging. Coupled to this we have developed an image registration technique resulting in a high-fidelity 4D reconstruction of the heart as it beats, with sub-cellular resolution, reduced photo-toxicity, and minimal post-processing artifacts. This approach has allowed us to visualize protein expression patterns at endogenous concentrations in transgenic zebrafish lines expressing cardiac–specific fluorescent markers.