Iain D. C. Tullis

Bio: Iain D. C. Tullis is an academic researcher from University of Oxford. The author has contributed to research in topics: Speckle pattern & Angular displacement. The author has an hindex of 13, co-authored 34 publications receiving 563 citations. Previous affiliations of Iain D. C. Tullis include University College London & Loughborough University.

A frequency multiplexed near-infrared topography system for imaging functional activation in the brain

Abstract: We have developed a novel near-infrared optical topography system that can acquire images of functional activation in the human brain at 10 frames per second using 32 detectors. The image acquisition rate is inversely proportional to the number of detectors, so the maximum acquisition rate using four detectors is 80Hz. 16 laser diode sources (8 at 785 and 8 at 850nm) are illuminated simultaneously, and each of 8 avalanche photodiode detectors records light from several sources at the same time. The contribution from each source is demultiplexed in software using fast Fourier transforms. This allows for a more flexible, smaller, and less complex system than is achievable using traditional hardware demodulation techniques, such as lock-in amplifiers. The system will eventually incorporate a total of 64 sources and 32 detectors, enabling the entire adult cortex to be imaged. The system is designed to be as flexible as possible, and to be applicable to a wide variety of experimental and clinical needs. To thi...

A frequency multiplexed near infra-red topography system for imaging functional activation in the brain

Abstract: We have developed a novel near-infrared optical topography system that can acquire images at 10 frames per second. It uses frequency multiplexed sources, and FFT detection.

Identifying Ureters In Situ Under Fluorescence During Laparoscopic and Open Colorectal Surgery.

Abstract: Trevor M. Yeung, MBBChir, MA, MRCS, DPhil, y Davide Volpi, PhD,z Iain D. C. Tullis, PhD,z Gary A. Nicholson, MD,y Nicolas Buchs, MD,y Chris Cunningham, MD, RCSEd,y Richard Guy, MD, FRCS,y Ian Lindsey, MBBS, FRACS,y Bruce George, MS, FRCS,y Oliver Jones, DM, FRCS,y Lai Mun Wang, MB, BCh, MRCP, FRCPath,§ Roel Hompes, MD,y Borivoj Vojnovic, PhD,z Freddie Hamdy, MD, FRCSEd (Urol), FRCS, FMedSci, and Neil J. Mortensen, MD, FRCS (Eng), Hon FRCPS (Glas), Hon FRCS (Ed) y

The p97-Ataxin 3 complex regulates homeostasis of the DNA damage response E3 ubiquitin ligase RNF8

Abstract: The E3 ubiquitin ligase RNF8 (RING finger protein 8) is a pivotal enzyme for DNA repair. However, RNF8 hyper-accumulation is tumour-promoting and positively correlates with genome instability, cancer cell invasion, metastasis and poor patient prognosis. Very little is known about the mechanisms regulating RNF8 homeostasis to preserve genome stability. Here, we identify the cellular machinery, composed of the p97/VCP ubiquitin-dependent unfoldase/segregase and the Ataxin 3 (ATX3) deubiquitinase, which together form a physical and functional complex with RNF8 to regulate its proteasome-dependent homeostasis under physiological conditions. Under genotoxic stress, when RNF8 is rapidly recruited to sites of DNA lesions, the p97-ATX3 machinery stimulates the extraction of RNF8 from chromatin to balance DNA repair pathway choice and promote cell survival after ionising radiation (IR). Inactivation of the p97-ATX3 complex affects the non-homologous end joining DNA repair pathway and hypersensitises human cancer cells to IR. We propose that the p97-ATX3 complex is the essential machinery for regulation of RNF8 homeostasis under both physiological and genotoxic conditions and that targeting ATX3 may be a promising strategy to radio-sensitise BRCA-deficient cancers.

The gray institute 'open' high-content, fluorescence lifetime microscopes

Abstract: We describe a microscopy design methodology and details of microscopes built to this 'open' design approach. These demonstrate the first implementation of time-domain fluorescence microscopy in a flexible automated platform with the ability to ease the transition of this and other advanced microscopy techniques from development to use in routine biology applications. This approach allows easy expansion and modification of the platform capabilities, as it moves away from the use of a commercial, monolithic, microscope body to small, commercial off-the-shelf and custom made modular components. Drawings and diagrams of our microscopes have been made available under an open license for noncommercial use at http://users.ox.ac.uk/~atdgroup. Several automated high-content fluorescence microscope implementations have been constructed with this design framework and optimized for specific applications with multiwell plates and tissue microarrays. In particular, three platforms incorporate time-domain FLIM via time-correlated single photon counting in an automated fashion. We also present data from experiments performed on these platforms highlighting their automated wide-field and laser scanning capabilities designed for high-content microscopy. Devices using these designs also form radiation-beam 'end-stations' at Oxford and Surrey Universities, showing the versatility and extendibility of this approach.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Recent advances in diffuse optical imaging.

Abstract: We review the current state-of-the-art of diffuse optical imaging, which is an emerging technique for functional imaging of biological tissue. It involves generating images using measurements of visible or near-infrared light scattered across large (greater than several centimetres) thicknesses of tissue. We discuss recent advances in experimental methods and instrumentation, and examine new theoretical techniques applied to modelling and image reconstruction. We review recent work on in vivo applications including imaging the breast and brain, and examine future challenges.

Relative biological effectiveness (RBE) values for proton beam therapy. Variations as a function of biological endpoint, dose, and linear energy transfer

Abstract: Proton therapy treatments are based on a proton RBE (relative biological effectiveness) relative to high-energy photons of 1.1. The use of this generic, spatially invariant RBE within tumors and normal tissues disregards the evidence that proton RBE varies with linear energy transfer (LET), physiological and biological factors, and clinical endpoint.Based on the available experimental data from published literature, this review analyzes relationships of RBE with dose, biological endpoint and physical properties of proton beams. The review distinguishes between endpoints relevant for tumor control probability and those potentially relevant for normal tissue complication. Numerous endpoints and experiments on sub-cellular damage and repair effects are discussed.Despite the large amount of data, considerable uncertainties in proton RBE values remain. As an average RBE for cell survival in the center of a typical spread-out Bragg peak (SOBP), the data support a value of ~1.15 at 2 Gy/fraction. The proton RBE increases with increasing LETd and thus with depth in an SOBP from ~1.1 in the entrance region, to ~1.15 in the center, ~1.35 at the distal edge and ~1.7 in the distal fall-off (when averaged over all cell lines, which may not be clinically representative). For small modulation widths the values could be increased. Furthermore, there is a trend of an increase in RBE as (α/β)x decreases. In most cases the RBE also increases with decreasing dose, specifically for systems with low (α/β)x. Data on RBE for endpoints other than clonogenic cell survival are too diverse to allow general statements other than that the RBE is, on average, in line with a value of ~1.1.This review can serve as a source for defining input parameters for applying or refining biophysical models and to identify endpoints where additional radiobiological data are needed in order to reduce the uncertainties to clinically acceptable levels.