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Sample records for time bioluminescence imaging

  1. Optimisation of acquisition time in bioluminescence imaging

    Taylor, Shelley L.; Mason, Suzannah K. G.; Glinton, Sophie; Cobbold, Mark; Styles, Iain B.; Dehghani, Hamid

    2015-03-01

    Decreasing the acquisition time in bioluminescence imaging (BLI) and bioluminescence tomography (BLT) will enable animals to be imaged within the window of stable emission of the bioluminescent source, a higher imaging throughput and minimisation of the time which an animal is anaesthetised. This work investigates, through simulation using a heterogeneous mouse model, two methods of decreasing acquisition time: 1. Imaging at fewer wavelengths (a reduction from five to three); and 2. Increasing the bandwidth of filters used for imaging. The results indicate that both methods are viable ways of decreasing the acquisition time without a loss in quantitative accuracy. Importantly, when choosing imaging wavelengths, the spectral attenuation of tissue and emission spectrum of the source must be considered, in order to choose wavelengths at which a high signal can be achieved. Additionally, when increasing the bandwidth of the filters used for imaging, the bandwidth must be accounted for in the reconstruction algorithm.

  2. Bioluminescence Imaging

    Sadikot, Ruxana T.; Blackwell, Timothy S.

    2005-01-01

    Bioluminescence refers to the process of visible light emission in living organisms. Bioluminescence imaging is a powerful methodology that has been developed over the last decade as a tool for molecular imaging of small laboratory animals, enabling the study of ongoing biological processes in vivo. This form of optical imaging is low cost and noninvasive and facilitates real-time analysis of disease processes at the molecular level in living organisms. In this article, we provide a brief int...

  3. Bioanalytical Applications of Real-Time ATP Imaging Via Bioluminescence

    Jason Alan Gruenhagen

    2003-12-12

    The research discussed within involves the development of novel applications of real-time imaging of adenosine 5'-triphosphate (ATP). ATP was detected via bioluminescence and the firefly luciferase-catalyzed reaction of ATP and luciferin. The use of a microscope and an imaging detector allowed for spatially resolved quantitation of ATP release. Employing this method, applications in both biological and chemical systems were developed. First, the mechanism by which the compound 48/80 induces release of ATP from human umbilical vein endothelial cells (HUVECs) was investigated. Numerous enzyme activators and inhibitors were utilized to probe the second messenger systems involved in release. Compound 48/80 activated a G{sub q}-type protein to initiate ATP release from HUVECs. Ca{sup 2+} imaging along with ATP imaging revealed that activation of phospholipase C and induction of intracellular Ca{sup 2+} signaling were necessary for release of ATP. Furthermore, activation of protein kinase C inhibited the activity of phospholipase C and thus decreased the magnitude of ATP release. This novel release mechanism was compared to the existing theories of extracellular release of ATP. Bioluminescence imaging was also employed to examine the role of ATP in the field of neuroscience. The central nervous system (CNS) was dissected from the freshwater snail Lymnaea stagnalis. Electrophysiological experiments demonstrated that the neurons of the Lymnaea were not damaged by any of the components of the imaging solution. ATP was continuously released by the ganglia of the CNS for over eight hours and varied from ganglion to ganglion and within individual ganglia. Addition of the neurotransmitters K{sup +} and serotonin increased release of ATP in certain regions of the Lymnaea CNS. Finally, the ATP imaging technique was investigated for the study of drug release systems. MCM-41-type mesoporous nanospheres were loaded with ATP and end-capped with mercaptoethanol functionalized CdS monocrystals. Aggregates of nanospheres were bathed in imaging solution, and ATP bioluminescence was monitored to investigated the release kinetics of the nanosphere drug delivery systems. Addition of disulfide bond-cleaving molecules induced uncapping of the nanospheres and subsequently, the release of ATP. Increasing the concentration of the uncapping molecule decreased the temporal maximum and increased the magnitude of release of encapsulated ATP from the nanospheres. Furthermore, the release kinetics from the nanospheres varied with the size of the particle aggregates.

  4. Timing of Imaging after D-Luciferin Injection Affects the Longitudinal Assessment of Tumor Growth Using In Vivo Bioluminescence Imaging

    Yusuke Inoue; Shigeru Kiryu; Makoto Watanabe; Arinobu Tojo; Kuni Ohtomo

    2010-01-01

    The peak signal or the signal at a predetermined, fixed time point after D-luciferin injection may be used for the quantitative analysis of in vivo bioluminescence imaging. We repeatedly performed sequential bioluminescence imaging after subcutaneous injection of D-luciferin in mice bearing subcutaneous tumors. The peak time in each measurement became shorter early after cell inoculation, presumably due to gradual establishment of intratumoral vasculature, and reached a plateau of about 10 mi...

  5. Timing of Imaging after D-Luciferin Injection Affects the Longitudinal Assessment of Tumor Growth Using In Vivo Bioluminescence Imaging

    Yusuke Inoue

    2010-01-01

    Full Text Available The peak signal or the signal at a predetermined, fixed time point after D-luciferin injection may be used for the quantitative analysis of in vivo bioluminescence imaging. We repeatedly performed sequential bioluminescence imaging after subcutaneous injection of D-luciferin in mice bearing subcutaneous tumors. The peak time in each measurement became shorter early after cell inoculation, presumably due to gradual establishment of intratumoral vasculature, and reached a plateau of about 10 min on day 10. Although the correlation between the signal at a fixed time point and the peak signal was high, the signal at 5 or 10 min normalized for the peak signal was lower for earlier days, which caused overestimation of tumor growth. The time course of the signals after D-luciferin injection may vary with time after cell inoculation, and this variation should be considered when determining the imaging protocol for quantitative bioluminescence tumor monitoring.

  6. Bioluminescence microscopy using a short focal-length imaging lens

    Ogoh, K; Akiyoshi, R.; May-Maw-Thet,; Sugiyama, T; Dosaka, S; Hatta-Ohashi, Y; Suzuki, H.

    2014-01-01

    Bioluminescence from cells is so dim that bioluminescence microscopy is performed using an ultra low-light imaging camera. Although the image sensor of such cameras has been greatly improved over time, such improvements have not been made commercially available for microscopes until now. Here, we customized the optical system of a microscope for bioluminescence imaging. As a result, bioluminescence images of cells could be captured with a conventional objective lens and colour imaging camera....

  7. BIOLUMINESCENCE IMAGING: PROGRESS AND APPLICATIONS

    Badr, Christian E.; Tannous, Bakhos A.

    2011-01-01

    Application of bioluminescence imaging has grown tremendously in the past decade and has significantly contributed to the core conceptual advances in biomedical research. This technology provides valuable means for monitoring of different biological processes for immunology, oncology, virology and neuroscience. In this review, we will discuss current trends in bioluminescence and its application in different fields with emphasis on cancer research.

  8. Real-time monitoring of cariogenic bacteria via bioluminescent imaging: A biodontic hypothesis

    Jafar Kolahi

    2016-01-01

    Full Text Available Introduction: Dental caries (tooth decay remains one of the most common chronic infectious disease in the world. Disclosure of camouflaged cariogenic bacteria will be a great motivation for better oral hygiene. The Hypothesis: At present, lux transposon cassette, Tn4001 luxABCDE Kmr, is available that could be used for stable bioluminescent transformation of a wide range of gram-positive bacteria, e.g. Streptococcus mutans and Lactobacillus. After this step, sensitive charge-coupled device (CCD camera could be used to detect the low levels of light emitted from bioluminescent cariogenic bacteria. Living imaging software would be used for analysis and three-dimensional (3D reconstruction of images. Evaluation of the Hypothesis: Entrance of transgenic organisms into the oral cavity should be done with great caution. Ethical consideration is necessary and primary animal studies are required. The main limitation of this technique will be oxygen. As mentioned previously, bioluminescent reactions need oxygen. Hence, bioluminescent imaging cannot be used for anaerobic bacteria, e.g., Streptococcus sobrinus.

  9. Bioluminescence imaging characteristics and application

    Bioluminescence imaging (BLI) by luciferase gene marked cells or DNA, in the presence of ATP and oxygen, catalytic oxidation reaction of fluorescein luminescence. So that it can directly monitor in vivo cell activity and gene behavior. In this paper, by comparing the BLI and MRI, PET, radiography of the similarities and differences, as well as about their cancer, stem cells and immune cells transportation, apoptosis and other aspects of the application, in order to better provide the basis for promoting the application of BLI. (authors)

  10. Noninvasive Bioluminescence Imaging in Small Animals

    Zinn, Kurt R.; Chaudhuri, Tandra R.; Szafran, April Adams; O’Quinn, Darrell; Weaver, Casey; Dugger, Kari; Lamar, Dale; Kesterson, Robert A.; Wang, Xiangdong; Frank, Stuart J.

    2008-01-01

    There has been a rapid growth of bioluminescence imaging applications in small animal models in recent years, propelled by the availability of instruments, analysis software, reagents, and creative approaches to apply the technology in molecular imaging. Advantages include the sensitivity of the technique as well as its efficiency, relatively low cost, and versatility. Bioluminescence imaging is accomplished by sensitive detection of light emitted following chemical reaction of the luciferase...

  11. In Vivo Bioluminescence Imaging of Intratumoral Bacteria.

    Cronin, Michelle; Akin, Ali R; Francis, Kevin P; Tangney, Mark

    2016-01-01

    This chapter describes the use of whole-body bioluminescent imaging (BLI) for the study of bacterial trafficking in live mice, with an emphasis on the use of bacteria in therapy of cancer. Bacteria present an attractive class of vector for cancer therapy, possessing a natural ability to grow preferentially within tumors following systemic administration. Bacteria engineered to express the lux gene cassette permit BLI detection of the bacteria and tumor sites concurrently. The location and levels of bacteria within tumors over time can be readily examined, visualized in two or three dimensions. The method is applicable to a wide range of bacterial species and tumor xenograft types. This article describes the protocol for analysis of bioluminescent bacteria within subcutaneous tumor-bearing mice. This powerful, and inexpensive, real-time imaging strategy represents an ideal method for the study of bacteria in vivo in the context of cancer research. This protocol outlines the procedure for studying lux-tagged Escherichia coli and Bifidobacterium breve in mice, demonstrating the spatial and temporal readout from 2D and 3D BLI achievable with whole-body in vivo luminescence imaging. PMID:26846803

  12. Bioluminescent imaging of Trypanosoma cruzi infection in Rhodnius prolixus

    Henriques Cristina

    2012-09-01

    Full Text Available Abstract Background Usually the analysis of the various developmental stages of Trypanosoma cruzi in the experimentally infected vertebrate and invertebrate hosts is based on the morphological observations of tissue fragments from animals and insects. The development of techniques that allow the imaging of animals infected with parasites expressing luciferase open up possibilities to follow the fate of bioluminescent parasites in infected vectors. Methods D-luciferin (60 μg was injected into the hemocoel of the whole insect before bioluminescence acquisition. In dissected insects, the whole gut was incubated with D-luciferin in PBS (300 μg/ml for ex vivo bioluminescence acquisition in the IVIS® Imaging System, Xenogen. Results Herein, we describe the results obtained with the luciferase gene integrated into the genome of the Dm28c clone of T. cruzi, and the use of these parasites to follow, in real time, the infection of the insect vector Rhodnius prolixus, by a non- invasive method. The insects were evaluated by in vivo bioluminescent imaging on the feeding day, and on the 7 th, 14 th, 21 st and 28 th days after feeding. To corroborate the bioluminescent imaging made in vivo, and investigate the digestive tract region, the insects were dissected. The bioluminescence emitted was proportional to the number of protozoans in regions of the gut. The same digestive tracts were also macerated to count the parasites in distinct morphological stages with an optical microscope, and for bioluminescence acquisition in a microplate using the IVIS® Imaging System. A positive correlation of parasite numbers and bioluminescence in the microplate was obtained. Conclusions This is the first report of bioluminescent imaging in Rhodnius prolixus infected with trypomastigotes of the Dm28c-luc stable strain, expressing firefly luciferase. In spite of the distribution limitations of the substrate (D-luciferin in the insect body, longitudinal evaluation of infected insects by bioluminescent imaging is a valuable tool. Bioluminescent imaging of the digestive tract infected with Dm28c-luc is highly sensitive and accurate method to track the fate of the parasite in the vector, in the crop, intestine and rectum. This methodology is useful to gain a better understanding of the parasite – insect vector interactions.

  13. In vivo cell tracking with bioluminescence imaging

    Kim, Jung Eun; Kalimuthu, Senthilkumar; Ahn, Byeong Cheol [Dept. of Nuclear Medicine, Kyungpook National University School of Medicine and Hospital, Daegu (Korea, Republic of)

    2015-03-15

    Molecular imaging is a fast growing biomedical research that allows the visual representation, characterization and quantification of biological processes at the cellular and subcellular levels within intact living organisms. In vivo tracking of cells is an indispensable technology for development and optimization of cell therapy for replacement or renewal of damaged or diseased tissue using transplanted cells, often autologous cells. With outstanding advantages of bioluminescence imaging, the imaging approach is most commonly applied for in vivo monitoring of transplanted stem cells or immune cells in order to assess viability of administered cells with therapeutic efficacy in preclinical small animal models. In this review, a general overview of bioluminescence is provided and recent updates of in vivo cell tracking using the bioluminescence signal are discussed.

  14. In vivo cell tracking with bioluminescence imaging

    Molecular imaging is a fast growing biomedical research that allows the visual representation, characterization and quantification of biological processes at the cellular and subcellular levels within intact living organisms. In vivo tracking of cells is an indispensable technology for development and optimization of cell therapy for replacement or renewal of damaged or diseased tissue using transplanted cells, often autologous cells. With outstanding advantages of bioluminescence imaging, the imaging approach is most commonly applied for in vivo monitoring of transplanted stem cells or immune cells in order to assess viability of administered cells with therapeutic efficacy in preclinical small animal models. In this review, a general overview of bioluminescence is provided and recent updates of in vivo cell tracking using the bioluminescence signal are discussed

  15. Comparison of image restoration methods for bioluminescence imaging

    Akkoul, Smaïl; Lédée, Roger; Leconge, Remy; Léger, Christophe; Harba, Rachid; Pesnel, Sabrina; Lerondel, Stéphanie; Lepape, Alain

    2008-01-01

    Bioluminescence imaging is a recent modality to visualize biological effects more especially for small animals. However the acquired images are degraded by diffusion and absorption phenomena from the tissue and by the acquisition system itself. In this paper, we use restoration methods to enhance the quality of bioluminescence images. We propose a model for image formation and an experimental determination of the PSF (Point Spread Function). Several methods of restoration are compared on test...

  16. Bioluminescence in vivo imaging of autoimmune encephalomyelitis predicts disease

    Steinman Lawrence

    2008-02-01

    Full Text Available Abstract Background Experimental autoimmune encephalomyelitis is a widely used animal model to understand not only multiple sclerosis but also basic principles of immunity. The disease is scored typically by observing signs of paralysis, which do not always correspond with pathological changes. Methods Experimental autoimmune encephalomyelitis was induced in transgenic mice expressing an injury responsive luciferase reporter in astrocytes (GFAP-luc. Bioluminescence in the brain and spinal cord was measured non-invasively in living mice. Mice were sacrificed at different time points to evaluate clinical and pathological changes. The correlation between bioluminescence and clinical and pathological EAE was statistically analyzed by Pearson correlation analysis. Results Bioluminescence from the brain and spinal cord correlates strongly with severity of clinical disease and a number of pathological changes in the brain in EAE. Bioluminescence at early time points also predicts severity of disease. Conclusion These results highlight the potential use of bioluminescence imaging to monitor neuroinflammation for rapid drug screening and immunological studies in EAE and suggest that similar approaches could be applied to other animal models of autoimmune and inflammatory disorders.

  17. Bioluminescent system for dynamic imaging of cell and animal behavior

    Hara-Miyauchi, Chikako [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Laboratory for Cell Function Dynamics, Brain Science Institute, RIKEN, Saitama 351-0198 (Japan); Department of Biophysics and Biochemistry, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Tokyo 113-8510 (Japan); Tsuji, Osahiko [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan); Hanyu, Aki [Division of Biochemistry, The Cancer Institute of the Japanese Foundation for Cancer Research, Tokyo 135-8550 (Japan); Okada, Seiji [Department of Advanced Medical Initiatives, Faculty of Medical Sciences, Kyushu University, Fukuoka 812-8582 (Japan); Yasuda, Akimasa [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan); Fukano, Takashi [Laboratory for Cell Function Dynamics, Brain Science Institute, RIKEN, Saitama 351-0198 (Japan); Akazawa, Chihiro [Department of Biophysics and Biochemistry, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, Tokyo 113-8510 (Japan); Nakamura, Masaya [Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo 160-8582 (Japan); Imamura, Takeshi [Department of Molecular Medicine for Pathogenesis, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295 (Japan); Core Research for Evolutional Science and Technology, The Japan Science and Technology Corporation, Tokyo 135-8550 (Japan); Matsuzaki, Yumi [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Okano, Hirotaka James, E-mail: hjokano@jikei.ac.jp [Department of Physiology, Keio University School of Medicine, Tokyo 160-8582 (Japan); Division of Regenerative Medicine Jikei University School of Medicine, Tokyo 150-8461 (Japan); and others

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer We combined a yellow variant of GFP and firefly luciferase to make ffLuc-cp156. Black-Right-Pointing-Pointer ffLuc-cp156 showed improved photon yield in cultured cells and transgenic mice. Black-Right-Pointing-Pointer ffLuc-cp156 enabled video-rate bioluminescence imaging of freely-moving animals. Black-Right-Pointing-Pointer ffLuc-cp156 mice enabled tracking real-time drug delivery in conscious animals. -- Abstract: The current utility of bioluminescence imaging is constrained by a low photon yield that limits temporal sensitivity. Here, we describe an imaging method that uses a chemiluminescent/fluorescent protein, ffLuc-cp156, which consists of a yellow variant of Aequorea GFP and firefly luciferase. We report an improvement in photon yield by over three orders of magnitude over current bioluminescent systems. We imaged cellular movement at high resolution including neuronal growth cones and microglial cell protrusions. Transgenic ffLuc-cp156 mice enabled video-rate bioluminescence imaging of freely moving animals, which may provide a reliable assay for drug distribution in behaving animals for pre-clinical studies.

  18. Bioluminescent system for dynamic imaging of cell and animal behavior

    Highlights: ► We combined a yellow variant of GFP and firefly luciferase to make ffLuc-cp156. ► ffLuc-cp156 showed improved photon yield in cultured cells and transgenic mice. ► ffLuc-cp156 enabled video-rate bioluminescence imaging of freely-moving animals. ► ffLuc-cp156 mice enabled tracking real-time drug delivery in conscious animals. -- Abstract: The current utility of bioluminescence imaging is constrained by a low photon yield that limits temporal sensitivity. Here, we describe an imaging method that uses a chemiluminescent/fluorescent protein, ffLuc-cp156, which consists of a yellow variant of Aequorea GFP and firefly luciferase. We report an improvement in photon yield by over three orders of magnitude over current bioluminescent systems. We imaged cellular movement at high resolution including neuronal growth cones and microglial cell protrusions. Transgenic ffLuc-cp156 mice enabled video-rate bioluminescence imaging of freely moving animals, which may provide a reliable assay for drug distribution in behaving animals for pre-clinical studies.

  19. Dynamic bioluminescence imaging for quantitative tumour burden assessment using IV or IP administration of d-luciferin: effect on intensity, time kinetics and repeatability of photon emission

    In vivo bioluminescence imaging (BLI) is a promising technique for non-invasive tumour imaging. d-luciferin can be administrated intraperitonealy or intravenously. This will influence its availability and, therefore, the bioluminescent signal. The aim of this study is to compare the repeatability of BLI measurement after IV versus IP administration of d-luciferin and assess the correlation between photon emission and histological cell count both in vitro and in vivo. Fluc-positive R1M cells were subcutaneously inoculated in nu/nu mice. Dynamic BLI was performed after IV or IP administration of d-luciferin. Maximal photon emission (PEmax) was calculated. For repeatability assessment, every acquisition was repeated after 4 h and analysed using Bland-Altman method. A second group of animals was serially imaged, alternating IV and IP administration up to 21 days. When mice were killed, PEmax after IV administration was correlated with histological cell number. The coefficients of repeatability were 80.2% (IV) versus 95.0% (IP). Time-to-peak is shorter, and its variance lower for IV (p max was 5.6 times higher for IV. A trend was observed towards lower photon emission per cell in larger tumours. IV administration offers better repeatability and better sensitivity when compared to IP. In larger tumours, multiple factors may contribute to underestimation of tumour burden. It might, therefore, be beneficial to test novel therapeutics on small tumours to enable an accurate evaluation of tumour burden. (orig.)

  20. In Vivo Bioluminescence Imaging of the Murine Pathogen Citrobacter rodentium

    Wiles, Siouxsie; Pickard, Karen M.; Peng, Katian; MacDonald, Thomas T.; Frankel, Gad

    2006-01-01

    Citrobacter rodentium is a natural mouse pathogen related to enteropathogenic and enterohemorrhagic Escherichia coli. We have previously utilized bioluminescence imaging (BLI) to determine the in vivo colonization dynamics of C. rodentium. However, due to the oxygen requirement of the bioluminescence system and the colonic localization of C. rodentium, in vivo localization studies were performed using harvested organs. Here, we report the detection of bioluminescent C. rodentium and commensal...

  1. Bioluminescence imaging of estrogen receptor activity during breast cancer progression

    Vantaggiato, Cristina; Dell’Omo, Giulia; Ramachandran, Balaji; Manni, Isabella; Radaelli, Enrico; Scanziani, Eugenio; Piaggio, Giulia; Maggi, Adriana; Ciana, Paolo

    2016-01-01

    Estrogen receptors (ER) are known to play an important regulatory role in mammary gland development as well as in its neoplastic transformation. Although several studies highlighted the contribution of ER signaling in the breast transformation, little is known about the dynamics of ER state of activity during carcinogenesis due to the lack of appropriate models for measuring the extent of receptor signaling in time, in the same animal. To this aim, we have developed a reporter mouse model for the non-invasive in vivo imaging of ER activity: the ERE-Luc reporter mouse. ERE-Luc is a transgenic mouse generated with a firefly luciferase (Luc) reporter gene driven by a minimal promoter containing an estrogen responsive element (ERE). This model allows to measure receptor signaling in longitudinal studies by bioluminescence imaging (BLI). Here, we have induced sporadic mammary cancers by treating systemically ERE-Luc reporter mice with DMBA (9,10-dimethyl 1,2-benzanthracene) and measured receptor signaling by in vivo imaging in individual animals from early stage until a clinically palpable tumor appeared in the mouse breast. We showed that DMBA administration induces an increase of bioluminescence in the whole abdominal area 6 h after treatment, the signal rapidly disappears. Several weeks later, strong bioluminescence is observed in the area corresponding to the mammary glands. In vivo and ex vivo imaging analysis demonstrated that this bioluminescent signal is localized in the breast area undergoing neoplastic transformation. We conclude that this non-invasive assay is a novel relevant tool to identify the activation of the ER signaling prior the morphological detection of the neoplastic transformation. PMID:27069764

  2. Bioluminescence.

    Jones, M. Gail

    1993-01-01

    Describes bioluminescence and the chemistry of how it occurs. Presents information for conducting the following classroom activities: (1) firefly mimic; (2) modeling deep-sea fish; (3) sea fireflies; and (4) the chemistry of light. (PR)

  3. Longitudinal Bioluminescence Imaging of the Dynamics of Doxorubicin Induced Apoptosis

    NIU, GANG; Zhu, Lei; Ho, Don N.; Zhang, Fan; Gao, Haokao; Quan, Qimeng; Hida, Naoki; Ozawa, Takeaki; Liu, Gang; CHEN, XIAOYUAN

    2013-01-01

    Objectives: Most chemotherapy agents cause tumor cell death primarily by the induction of apoptosis. The ability to noninvasively image apoptosis in vivo could dramatically benefit pre-clinical and clinical evaluation of chemotherapeutics targeting the apoptotic pathway. This study aims to visualize the dynamics of apoptotic process with temporal bioluminescence imaging (BLI) using an apoptosis specific bioluminescence reporter gene. Methods: Both UM-SCC-22B human head and neck squamous carci...

  4. Image-guided simulation for bioluminescence tomographic imaging

    Kumar, Durairaj; Cong, Wenxiang; Thiesse, Jacqueline; Nixon, Earl; Meinel, John, Jr.; Cong, Alex; McLennan, Geoffrey; Hoffman, Eric A.; Ming, Jiang; Wang, Ge

    2005-04-01

    Noninvasive imaging of the reporter gene expression based on bioluminescence is playing an important role in the areas of cancer biology, cell biology, and gene therapy. The central problem for the bioluminescence tomography (BLT) we are developing is to reconstruct the underlying bioluminescent source distribution in a small animal using a modality fusion approach. To solve this inversion problem, a mathematical model of the mouse is built from a CT/micro-CT scan, which enables the assignment of optical parameters to various regions in the model. This optical geometrical model is used in the Monte Carlo simulation to calculate the flux distribution on the animal body surface, as a key part of the BLT process. The model development necessitates approximations in surface simplification, and so on. It leads to the model mismatches of different kinds. To overcome such discrepancies, instead of developing a mathematical model, segmented CT images are directly used in our simulation software. While the simulation code is executed, those images that are relevant are assessed according to the location of the propagating photon. Depending upon the segmentation rules including the pixel value range, appropriate optical parameters are selected for statistical sampling of the free path and weight of the photon. In this paper, we report luminescence experiments using a physical mouse phantom to evaluate this image-guided simulation procedure, which suggest both the feasibility and some advantages of this technique over the existing methods.

  5. Bioluminescence tomography improves quantitative accuracy for pre-clinical imaging

    Guggenheim, James A.; Basevi, Hector R. A.; Styles, Iain B.; Frampton, Jon; Dehghani, Hamid

    2013-06-01

    A study is presented that demonstrates that bioluminescence tomography can reconstruct accurate 3D images of internal light sources placed at a range of depths within a physical phantom and that it provides more reliable quantitative data than standard bioluminescence imaging. Specifically, it is shown that when imaging sources at depths ranging from 5 to 15mm, estimates of total source strength are stable to within +/-11% using tomography whilst values deduced by traditional methods vary 10-fold. Additionally, the tomographic approach correctly localises sources to within 1.5mm error in all cases considered.

  6. Continuous, real-time bioimaging of chemical bioavailability and toxicology using autonomously bioluminescent human cell lines

    Xu, Tingting; Close, Dan M.; Webb, James D.; Price, Sarah L.; Ripp, Steven A.; Sayler, Gary S.

    2013-05-01

    Bioluminescent imaging is an emerging biomedical surveillance strategy that uses external cameras to detect in vivo light generated in small animal models of human physiology or in vitro light generated in tissue culture or tissue scaffold mimics of human anatomy. The most widely utilized of reporters is the firefly luciferase (luc) gene; however, it generates light only upon addition of a chemical substrate, thus only generating intermittent single time point data snapshots. To overcome this disadvantage, we have demonstrated substrate-independent bioluminescent imaging using an optimized bacterial bioluminescence (lux) system. The lux reporter produces bioluminescence autonomously using components found naturally within the cell, thereby allowing imaging to occur continuously and in real-time over the lifetime of the host. We have validated this technology in human cells with demonstrated chemical toxicological profiling against exotoxin exposures at signal strengths comparable to existing luc systems (~1.33 × 107 photons/second). As a proof-in-principle demonstration, we have engineered breast carcinoma cells to express bioluminescence for real-time screening of endocrine disrupting chemicals and validated detection of 17β-estradiol (EC50 = ~ 10 pM). These and other applications of this new reporter technology will be discussed as potential new pathways towards improved models of target chemical bioavailability, toxicology, efficacy, and human safety.

  7. Filtering and deconvolution for bioluminescence imaging of small animals

    This thesis is devoted to analysis of bioluminescence images applied to the small animal. This kind of imaging modality is used in cancerology studies. Nevertheless, some problems are related to the diffusion and the absorption of the tissues of the light of internal bioluminescent sources. In addition, system noise and the cosmic rays noise are present. This influences the quality of the images and makes it difficult to analyze. The purpose of this thesis is to overcome these disturbing effects. We first have proposed an image formation model for the bioluminescence images. The processing chain is constituted by a filtering stage followed by a deconvolution stage. We have proposed a new median filter to suppress the random value impulsive noise which corrupts the acquired images; this filter represents the first block of the proposed chain. For the deconvolution stage, we have performed a comparative study of various deconvolution algorithms. It allowed us to choose a blind deconvolution algorithm initialized with the estimated point spread function of the acquisition system. At first, we have validated our global approach by comparing our obtained results with the ground truth. Through various clinical tests, we have shown that the processing chain allows a significant improvement of the spatial resolution and a better distinction of very close tumor sources, what represents considerable contribution for the users of bioluminescence images. (author)

  8. Space application research of EMCCDs for bioluminescence imaging

    Zhang, Tao

    The detection of bioluminescense is widely used on the ground, while the detection of bioluminescence in space is still at the stage of detecting bright bioluminescense. With the rapid development of research in Space Life Sciences, it will be necessary to develop a detection technology to detect weak bioluminescense. Compared to other low-light detection techniques for ground, there are more advantages of EMCCDs for space application. Build a space bioluminescence imaging detection system, analysis the feasibility and capability of its will be significant. Co-Author:Xie Zongbao,Zheng Weibo

  9. Computer-aided photometric analysis of dynamic digital bioluminescent images

    Gorski, Zbigniew; Bembnista, T.; Floryszak-Wieczorek, J.; Domanski, Marek; Slawinski, Janusz

    2003-04-01

    The paper deals with photometric and morphologic analysis of bioluminescent images obtained by registration of light radiated directly from some plant objects. Registration of images obtained from ultra-weak light sources by the single photon counting (SPC) technique is the subject of this work. The radiation is registered by use of a 16-bit charge coupled device (CCD) camera "Night Owl" together with WinLight EG&G Berthold software. Additional application-specific software has been developed in order to deal with objects that are changing during the exposition time. Advantages of the elaborated set of easy configurable tools named FCT for a computer-aided photometric and morphologic analysis of numerous series of quantitatively imperfect chemiluminescent images are described. Instructions are given how to use these tools and exemplified with several algorithms for the transformation of images library. Using the proposed FCT set, automatic photometric and morphologic analysis of the information hidden within series of chemiluminescent images reflecting defensive processes in poinsettia (Euphorbia pulcherrima Willd) leaves affected by a pathogenic fungus Botrytis cinerea is revealed.

  10. Development of Quantification Method for Bioluminescence Imaging

    Optical molecular luminescence imaging is widely used for detection and imaging of bio-photons emitted by luminescent luciferase activation. The measured photons in this method provide the degree of molecular alteration or cell numbers with the advantage of high signal-to-noise ratio. To extract useful information from the measured results, the analysis based on a proper quantification method is necessary. In this research, we propose a quantification method presenting linear response of measured light signal to measurement time. We detected the luminescence signal by using lab-made optical imaging equipment of animal light imaging system (ALIS) and different two kinds of light sources. One is three bacterial light-emitting sources containing different number of bacteria. The other is three different non-bacterial light sources emitting very weak light. By using the concept of the candela and the flux, we could derive simplified linear quantification formula. After experimentally measuring light intensity, the data was processed with the proposed quantification function. We could obtain linear response of photon counts to measurement time by applying the pre-determined quantification function. The ratio of the re-calculated photon counts and measurement time present a constant value although different light source was applied. The quantification function for linear response could be applicable to the standard quantification process. The proposed method could be used for the exact quantitative analysis in various light imaging equipment with presenting linear response behavior of constant light emitting sources to measurement time

  11. A New Diagnostic System in Cancer Research: Bioluminescent Imaging (BLI)

    D?KMEN, Z. Gnnur; GELLERT, Ginelle; DO?AN, Pakize; Mason, Ralph; Antich, Peter; Richer, Edmond, 1560-1631; Wright, Woodring E

    2005-01-01

    Bioluminescent imaging (BLI) is particularly well suited for imaging small animals, and it can be readily used by scientists who are already routinely using the luciferase gene as a reporter in cell-based assays. This strategy relies on ATP and an O2 dependent photochemical reaction between luciferin and luciferase, resulting in the release of photons from only live cells. In BLI, the intensity of the light detected by the device is proportional to the intensity of light emitted and the relat...

  12. Infection with adenovirus-mediated luciferase reporter gene in mesenchymal stem cells and bioluminescence imaging

    Objective: To construct adenovirus vector containing firefly luciferase reporter gene (Ad-Luc) and infect bone marrow mesenchymal stem cells (BMSC), then to take bioluminescence imaging in vitro and in vivo for identification. Methods: The luciferase gene was amplified with PCR from psiCHECK-2 plasmid and cloned into the adenoviral shuttle vector (pShuttle-CMV). It was confirmed by Nhe Ⅰ/Xba Ⅰ digestion and sequencing. PShuttle-CMV-Luc and backbone vector (pAdeno) were homologous recombined. Then the recombinant plasmid was packaged in HEK293 cells and the virus titer was detected. The BMSC were infected by the recombinant adenovirus. The bioluminescence imaging in vitro was performed to determine the best multiplicity of infection (MOI), and the relationship between bioluminescence intensity and MOI was analyzed by curve fitting regression analysis. Viability was evaluated via Trypan blue staining. The transfected BMSC (1 × 106) were implanted into the muscles of forelimb of SD rats,and then tracked by bioluminescence imaging in vivo. Cell viability was compared using two-way repeated measures analysis of variance between groups. Results: Enzyme digestion and sequence analysis indicated that Ad-Luc was successfully constructed. The virus titer was 1 × 1010 plaque forming unit (PFU)/ml. The bioluminescence detection in vitro showed that Ad-Luc could infect BMSC high efficiently to express luciferase and the best MOI was 50. The bioluminescence intensity enhanced with increase of MOI (R2 =0.98). No statistically significant difference was found in cell viability between transfected and untransfected BMSC at 1, 3, 5, 7 d. The cell survival rates were (92.5±2.3)% vs (94.1±1.8)%, (91.4±0.9)% vs (92.7±2.0)%, (92.1±1.6)% vs (93.3± 2.4)%, (91.9 ± 1.5)% vs (93.0 ± 3.1)%, respectively (F=4.38, P>0.05). The bioluminescence imaging in vivo showed that BMSC survived 1, 3, 7 d after implantation. However, bioluminescence signal decreased gradually over time. Conclusion: It is feasible to apply the optical reporter gene imaging for tracing transplanted stem cells in vitro and in vivo due to the effective transformation of luciferase reporter gene into BMSC by adenovirus vector. (authors)

  13. Hyperspectral and multispectral bioluminescence optical tomography for small animal imaging

    For bioluminescence imaging studies in small animals, it is important to be able to accurately localize the three-dimensional (3D) distribution of the underlying bioluminescent source. The spectrum of light produced by the source that escapes the subject varies with the depth of the emission source because of the wavelength-dependence of the optical properties of tissue. Consequently, multispectral or hyperspectral data acquisition should help in the 3D localization of deep sources. In this paper, we describe a framework for fully 3D bioluminescence tomographic image acquisition and reconstruction that exploits spectral information. We describe regularized tomographic reconstruction techniques that use semi-infinite slab or FEM-based diffusion approximations of photon transport through turbid media. Singular value decomposition analysis was used for data dimensionality reduction and to illustrate the advantage of using hyperspectral rather than achromatic data. Simulation studies in an atlas-mouse geometry indicated that sub-millimeter resolution may be attainable given accurate knowledge of the optical properties of the animal. A fixed arrangement of mirrors and a single CCD camera were used for simultaneous acquisition of multispectral imaging data over most of the surface of the animal. Phantom studies conducted using this system demonstrated our ability to accurately localize deep point-like sources and show that a resolution of 1.5 to 2.2 mm for depths up to 6 mm can be achieved. We also include an in vivo study of a mouse with a brain tumour expressing firefly luciferase. Co-registration of the reconstructed 3D bioluminescent image with magnetic resonance images indicated good anatomical localization of the tumour

  14. In Vivo Mouse Bioluminescence Tomography with Radionuclide-Based Imaging Validation

    Lu, Yujie; Machado, Hidevaldo B.; Bao, Qinan; Stout, David; Herschman, Harvey; Chatziioannou, Arion F.

    2010-01-01

    Introduction Bioluminescence imaging, especially planar bioluminescence imaging, has been extensively applied in in vivo preclinical biological research. Bioluminescence tomography (BLT) has the potential to provide more accurate imaging information due to its 3D reconstruction compared with its planar counterpart. Methods In this work, we introduce a positron emission tomography (PET) radionuclide imaging-based strategy to validate the BLT results. X-ray computed tomography, PET, spectrally ...

  15. Bioluminescent imaging of Trypanosoma cruzi infection in Rhodnius prolixus

    Henriques Cristina; Castro Daniele P; Gomes Leonardo HF; Garcia Eloi S; de Souza Wanderley

    2012-01-01

    Abstract Background Usually the analysis of the various developmental stages of Trypanosoma cruzi in the experimentally infected vertebrate and invertebrate hosts is based on the morphological observations of tissue fragments from animals and insects. The development of techniques that allow the imaging of animals infected with parasites expressing luciferase open up possibilities to follow the fate of bioluminescent parasites in infected vectors. Methods D-luciferin (60 μg) was injected into...

  16. In vivo fluorescence imaging of the reticuloendothelial system using quantum dots in combination with bioluminescent tumour monitoring

    We characterised in vivo fluorescence imaging (FLI) of the reticuloendothelial system using quantum dots (QD) and investigated its use in combination with in vivo bioluminescence imaging (BLI). In vivo FLI was performed in five mice repeatedly after the intravenous administration of QD without conjugation to targeting ligands. Ex vivo FLI of the excised organs was performed 24 h after QD injection in three mice. Seven days after intravenous inoculation of luciferase-expressing model cells of a haematological malignancy, mice were injected with the QD or saline (n = 5 each), and combined BLI/FLI was performed repeatedly. Additional five mice inoculated with the tumour cells were examined by in vivo BLI/FLI, and the structures harbouring bioluminescent foci were determined by ex vivo BLI. The utility of combining FLI with bioluminescent tumour monitoring was evaluated. In vivo FLI after QD injection allowed long-term, repeated observation of the reticuloendothelial system in individual mice, although fluorescence intensity and image contrast gradually decreased over time. Ex vivo FLI verified selective accumulation in reticuloendothelial structures. The administration of QD did not affect whole-body bioluminescent signal intensities during longitudinal tumour monitoring. In vivo BLI/FLI, accompanied by fusion of both images, improved the accuracy and confidence level of the localisation of the bioluminescent foci. In vivo FLI using QD provides an overview of the reticuloendothelial system in living mice. In combination with bioluminescent tumour monitoring, fluorescent reticuloendothelial imaging is expected to provide valuable information for lesion localisation. (orig.)

  17. Filtering and deconvolution for bioluminescence imaging of small animals; Filtrage et deconvolution en imagerie de bioluminescence chez le petit animal

    Akkoul, S.

    2010-06-22

    This thesis is devoted to analysis of bioluminescence images applied to the small animal. This kind of imaging modality is used in cancerology studies. Nevertheless, some problems are related to the diffusion and the absorption of the tissues of the light of internal bioluminescent sources. In addition, system noise and the cosmic rays noise are present. This influences the quality of the images and makes it difficult to analyze. The purpose of this thesis is to overcome these disturbing effects. We first have proposed an image formation model for the bioluminescence images. The processing chain is constituted by a filtering stage followed by a deconvolution stage. We have proposed a new median filter to suppress the random value impulsive noise which corrupts the acquired images; this filter represents the first block of the proposed chain. For the deconvolution stage, we have performed a comparative study of various deconvolution algorithms. It allowed us to choose a blind deconvolution algorithm initialized with the estimated point spread function of the acquisition system. At first, we have validated our global approach by comparing our obtained results with the ground truth. Through various clinical tests, we have shown that the processing chain allows a significant improvement of the spatial resolution and a better distinction of very close tumor sources, what represents considerable contribution for the users of bioluminescence images. (author)

  18. In Vivo Bioluminescence Imaging of Cell Differentiation in Biomaterials: A Platform for Scaffold Development

    Bag, Juli R; Aguilar, Elisabeth; Alieva, Maria; Soler-Botija, Carolina; Vila, Olaia F.; Claros, Silvia; Jos A. Andrades; Jos BECERRA; Rubio, Nuria; Blanco, Jernimo

    2012-01-01

    In vivo testing is a mandatory last step in scaffold development. Agile longitudinal noninvasive real-time monitoring of stem cell behavior in biomaterials implanted in live animals should facilitate the development of scaffolds for tissue engineering. We report on a noninvasive bioluminescence imaging (BLI) procedure for simultaneous monitoring of changes in the expression of multiple genes to evaluate scaffold performance in vivo. Adipose tissue-derived stromal mensenchymal cells were duall...

  19. Impact of Anesthesia Protocols on In Vivo Bioluminescent Bacteria Imaging Results

    Chuzel, Thomas; Sanchez, Violette; Vandamme, Marc; Martin, Stéphane; Flety, Odile; Pager, Aurélie; Chabanel, Christophe; Magnier, Luc; Foskolos, Marie; Petit, Océane; Rokbi, Bachra; Chereul, Emmanuel

    2015-01-01

    Infectious murine models greatly benefit from optical imaging using bioluminescent bacteria to non-invasively and repeatedly follow in vivo bacterial infection. In this context, one of the most critical parameters is the bioluminescence sensitivity to reliably detect the smallest number of bacteria. Another critical point is the anesthetic approaches that have been demonstrated to impact the bioluminescence flux emission in studies with luciferase-transfected tumor cells. However, this impact...

  20. Noninvasive bioluminescence imaging of olfactory ensheathing glia and schwann cells following transplantation into the lesioned rat spinal cord.

    Roet, Kasper C D; Eggers, Ruben; Verhaagen, Joost

    2012-01-01

    In this study, we assess the feasibility of bioluminescence imaging to monitor the survival of Schwann cells (SCs) and olfactory ensheathing glia cells (OECs) after implantation in the lesioned spinal cord of adult rats. To this end, purified SCs and OECs were genetically modified with lentiviral vectors encoding luciferase-2 and GFP and implanted in the lesioned dorsal column. The bioluminescent signal was monitored for over 3 months, and at 7 and 98 days postsurgery, the signal was compared to standard histological analysis of GFP expression in the spinal cords. The temporal profile of the bioluminescent signal showed three distinct phases for both cell types. (I) A relatively stable signal in the first week. (II) A progressive decline in signal strength in the second and third week. (III) After the third week, the average bioluminescent signal stabilized for both cell types. Interestingly, in the first week, the peak of the bioluminescent signal after luciferin injection was delayed when compared to later time points. Similar to in vitro, our data indicated a linear relationship between the in vivo bioluminescent signal and the GFP signal of the SCs and OECs in the spinal cords when the results of both the 7 and 98 day time points are combined. This is the first report of the use of in vivo bioluminescence to monitor cell survival in the lesioned rat spinal cord. Bioluminescence could be a potentially powerful, noninvasive strategy to examine the efficacy of treatments that aim to improve the survival of proregenerative cells transplanted in the injured rat spinal cord. PMID:22449606

  1. Assessing laser-tissue damage with bioluminescent imaging

    Wilmink, Gerald J.; Opalenik, Susan R.; Beckham, Josh T.; Davidson, Jeffrey M.; Jansen, Eric D.

    2006-07-01

    Effective medical laser procedures are achieved by selecting laser parameters that minimize undesirable tissue damage. Traditionally, human subjects, animal models, and monolayer cell cultures have been used to study wound healing, tissue damage, and cellular effects of laser radiation. Each of these models has significant limitations, and consequently, a novel skin model is needed. To this end, a highly reproducible human skin model that enables noninvasive and longitudinal studies of gene expression was sought. In this study, we present an organotypic raft model (engineered skin) used in combination with bioluminescent imaging (BLI) techniques. The efficacy of the raft model was validated and characterized by investigating the role of heat shock protein 70 (hsp70) as a sensitive marker of thermal damage. The raft model consists of human cells incorporated into an extracellular matrix. The raft cultures were transfected with an adenovirus containing a murine hsp70 promoter driving transcription of luciferase. The model enables quantitative analysis of spatiotemporal expression of proteins using BLI. Thermal stress was induced on the raft cultures by means of a constant temperature water bath or with a carbon dioxide (CO2) laser (λ=10.6 µm, 0.679 to 2.262 W/cm2, cw, unfocused Gaussian beam, ωL=4.5 mm, 1 min exposure). The bioluminescence was monitored noninvasively with an IVIS 100 Bioluminescent Imaging System. BLI indicated that peak hsp70 expression occurs 4 to 12 h after exposure to thermal stress. A minimum irradiance of 0.679 W/cm2 activated the hsp70 response, and a higher irradiance of 2.262 W/cm2 was associated with a severe reduction in hsp70 response due to tissue ablation. Reverse transcription polymerase chain reaction demonstrated that hsp70 mRNA levels increased with prolonged heating exposures. Enzyme-linked immunosorbent protein assays confirmed that luciferase was an accurate surrogate for hsp70 intracellular protein levels. Hematoxylin and eosin stains verified the presence of the thermally denatured tissue regions. Immunohistochemical analyses confirmed that maximal hsp70 expression occurred at a depth of 150 µm. Bioluminescent microscopy was employed to corroborate these findings. These results indicate that quantitative BLI in engineered tissue equivalents provides a powerful model that enables sequential gene expression studies. Such a model can be used as a high throughput screening platform for laser-tissue interaction studies.

  2. DEVELOPMENT OF A DUAL MODALITY TOMOGRAPHIC IMAGING SYSTEM FOR BIOLUMINESCENCE AND PET

    CHATZIIOANNOU, ARION

    2011-12-21

    The goal of this proposal was to develop a new hybrid imaging modality capable to simultaneously image optical bioluminescence signals, as well as radionuclide emissions from the annihilation of positrons originating from molecular imaging probes in preclinical mouse models. This new technology enables the simultaneous in-vivo measurements of both emissions that could be produced from a single or a combination of two different biomarkers. It also facilitates establishing the physical limitations of bioluminescence imaging, its tomographic and spectral image reconstruction potential and the quantification of bioluminescence signals.

  3. Bioluminescence Imaging of an Immunocompetent Animal Model for Glioblastoma

    Clark, Aaron J.; Fakurnejad, Shayan; Ma, Quanhong; Hashizume, Rintaro

    2016-01-01

    In contrast to commonly reported human glioma xenograft animal models, GL261 murine glioma xenografts recapitulate nearly all relevant clinical and histopathologic features of the human disease. When GL261 cells are implanted intracranially in syngeneic C57BL/6 mice, the model has the added advantage of maintaining an intact immune microenvironment. Stable expression of luciferase in GL261 cells allows non-invasive cost effective bioluminescence monitoring of intracranial tumor growth. We have recently demonstrated that luciferase expression in GL261 cells does not affect the tumor growth properties, tumor cell immunomodulatory cytokine expression, infiltration of immune cells into the tumor, or overall survival of animals bearing the intracranial tumor. Therefore, it appears that the GL261 luciferase glioma model can be useful in the study of novel chemotherapeutic and immunotherapeutic modalities. Here we report the technique for generating stable luciferase expression in GL261 cells and how to study the in vitro and in vivo growth of the tumor cells by bioluminescence imaging. PMID:26863490

  4. Bioluminescence Imaging of an Immunocompetent Animal Model for Glioblastoma.

    Clark, Aaron J; Fakurnejad, Shayan; Ma, Quanhong; Hashizume, Rintaro

    2016-01-01

    In contrast to commonly reported human glioma xenograft animal models, GL261 murine glioma xenografts recapitulate nearly all relevant clinical and histopathologic features of the human disease. When GL261 cells are implanted intracranially in syngeneic C57BL/6 mice, the model has the added advantage of maintaining an intact immune microenvironment. Stable expression of luciferase in GL261 cells allows non-invasive cost effective bioluminescence monitoring of intracranial tumor growth. We have recently demonstrated that luciferase expression in GL261 cells does not affect the tumor growth properties, tumor cell immunomodulatory cytokine expression, infiltration of immune cells into the tumor, or overall survival of animals bearing the intracranial tumor. Therefore, it appears that the GL261 luciferase glioma model can be useful in the study of novel chemotherapeutic and immunotherapeutic modalities. Here we report the technique for generating stable luciferase expression in GL261 cells and how to study the in vitro and in vivo growth of the tumor cells by bioluminescence imaging. PMID:26863490

  5. In vivo bioluminescence and reflectance imaging of multiple organs in bioluminescence reporter mice by bundled-fiber-coupled microscopy

    Ando, Yoriko; Sakurai, Takashi; Koida, Kowa; Tei, Hajime; Hida, Akiko; Nakao, Kazuki; Natsume, Mistuo; Numano, Rika

    2016-01-01

    Bioluminescence imaging (BLI) is used in biomedical research to monitor biological processes within living organisms. Recently, fiber bundles with high transmittance and density have been developed to detect low light with high resolution. Therefore, we have developed a bundled-fiber-coupled microscope with a highly sensitive cooled-CCD camera that enables the BLI of organs within the mouse body. This is the first report of in vivo BLI of the brain and multiple organs in luciferase-reporter mice using bundled-fiber optics. With reflectance imaging, the structures of blood vessels and organs can be seen clearly with light illumination, and it allowed identification of the structural details of bioluminescence images. This technique can also be applied to clinical diagnostics in a low invasive manner. PMID:27231601

  6. ATP binding cassette transporters modulate both coelenterazine- and D-luciferin- based bioluminescence imaging

    Huang, Ruimin; Vider, Jelena; Serganova, Inna; Blasberg, Ronald G.

    2011-01-01

    Bioluminescence imaging (BLI) of luciferase reporters provides a cost-effective and sensitive means to image biological processes. However, transport of luciferase substrates across the cell membrane does affect BLI-readout-intensity from intact living cells.

  7. Characterization of sevoflurane effects on Per2 expression using ex vivo bioluminescence imaging of the suprachiasmatic nucleus in transgenic rats.

    Matsuo, Izumi; Iijima, Norio; Takumi, Ken; Higo, Shimpei; Aikawa, Satoko; Anzai, Megumi; Ishii, Hirotaka; Sakamoto, Atsuhiro; Ozawa, Hitoshi

    2016-06-01

    The inhalation anesthetic sevoflurane suppresses Per2 expression in the suprachiasmatic nucleus (SCN) in rodents. Here, we investigated the intra-SCN regional specificity, time-dependency, and pharmacological basis of sevoflurane-effects. Bioluminescence image was taken from the SCN explants of mPer2 promoter-destabilized luciferase transgenic rats, and each small regions of interest (ROI) of the image was analyzed. Sevoflurane suppressed bioluminescence in all ROIs, suggesting that all regions in the SCN are sensitive to sevoflurane. Clear time-dependency in sevoflurane effects were also observed; application during the trough phase of the bioluminescence cycle suppressed the subsequent increase in bioluminescence and resulted in a phase delay of the cycle; sevoflurane applied during the middle of the ascending phase induced a phase advance; sevoflurane on the descending phase showed no effect. These results indicate that the sevoflurane effect may depend on the intrinsic state of circadian machinery. Finally, we examined the involvement of GABAergic signal transduction in the sevoflurane effect. Co-application of both GABAA and GABAB receptor antagonists completely blocked the effect of sevoflurane on the bioluminescence rhythm, suggesting that sevoflurane inhibits Per2 expression via GABAergic signal transduction. Current study elucidated the anesthetic effects on the molecular mechanisms of circadian rhythm. PMID:26696094

  8. In vivo heterogeneous tomographic bioluminescence imaging via a higher-order approximation forward model

    Liu, Kai; Tian, Jie, Sr.; Qin, Chenghu; Yang, Xin; Zhu, Shouping; Han, Dong; Wu, Ping; Dai, Xiaoqian

    2011-03-01

    In vivo bioluminescence imaging (BLI) has played a more and more important role in biomedical research of small animals. Tomographic bioluminescence imaging (TBI) further translates the BLI optical information into three-dimensional bioluminescent source distribution, which could greatly facilitate applications in related studies. Although the diffusion approximation (DA) is one of the most widely-used forward models, higher-order approximations are still needed for in vivo small animal imaging. In this work, as a relatively accurate and higher-order approximation theory, a simplified spherical harmonics approximation (SPN) is applied for heterogeneous tomographic bioluminescence imaging in vivo. Furthermore, coupled with the SPN, a generalized graph cuts optimization approach is utilized, making BLT reconstructions fast and suit for the whole body of small animals. Heterogeneous in vivo experimental reconstructions via the higher-order approximation model demonstrate higher tomographic imaging quality, which is shown the capability for practical biomedical tomographic imaging applications.

  9. U-SPECT-BioFluo: an integrated radionuclide, bioluminescence, and fluorescence imaging platform

    2014-01-01

    Background In vivo bioluminescence, fluorescence, and single-photon emission computed tomography (SPECT) imaging provide complementary information about biological processes. However, to date these signatures are evaluated separately on individual preclinical systems. In this paper, we introduce a fully integrated bioluminescence-fluorescence-SPECT platform. Next to an optimization in logistics and image fusion, this integration can help improve understanding of the optical imaging (OI) resul...

  10. U-SPECT-BioFluo: an integrated radionuclide, bioluminescence, and fluorescence imaging platform

    van Oosterom, Matthias N; Kreuger, Rob; Buckle, Tessa; Mahn, Wendy A; Bunschoten, Anton; Josephson, Lee; van Leeuwen, Fijs WB; Beekman, Freek J

    2014-01-01

    Background: In vivo bioluminescence, fluorescence, and single-photon emission computed tomography (SPECT) imaging provide complementary information about biological processes. However, to date these signatures are evaluated separately on individual preclinical systems. In this paper, we introduce a fully integrated bioluminescence-fluorescence-SPECT platform. Next to an optimization in logistics and image fusion, this integration can help improve understanding of the optical imaging (OI) resu...

  11. A practical method to determine the light source distribution in bioluminescent imaging

    Cong, Wenxiang; Kumar, Durairaj; Liu, Yi; Cong, Alexander; Wang, Ge

    2004-10-01

    Optical signatures of tumor cells may be generated by expression of reporter genes encoding bioluminescent/fluorescent proteins. Bioluminescent imaging is a novel technique that identifies such light sources from the light flux detected on the surface of a small animal. This technique can effectively evaluate tumor cell growth and regression in response to various therapies in medical research, drug development and gene therapy. In this paper, the diffusion approximation is employed to describe the propagation of photons through biological tissues. Then, a practical method is proposed for localizing and quantifying bioluminescent sources from external bioluminescent signals. This method incorporates prior knowledge on permissible source regions, and transforms the inverse bioluminescent problem into a finite element-based constrained optimization procedure. This approach is validated and evaluated with ideal and noise data in numerical simulation.

  12. High resolution in vitro bioluminescence imaging using a multimodal optical system

    Altabella, L.; Gigliotti, C. R.; Perani, L.; Crippa, M. P.; Boschi, F.; Spinelli, A. E.

    2016-01-01

    Bioluminescence in vitro studies are usually performed with dedicated microscopes. In this work, we developed a novel image recovery algorithm and a multimodal system prototype to perform bioluminescence microscopy. We performed a feasibility study using GEANT4 Monte Carlo (MC) simulation of bioluminescent cells acquired at low SNR frames and processed using a Super Resolution Regularization Algorithm (SRRA). The method was also tested using in vitro cell acquisition. The results obtained with MC simulations showed an improvement in the spatial resolution from 90 μ m to 10 μ m and from 110 μ m to 13 μ m for in vitro imaging of mesothelioma cells.

  13. Monitoring and quantitative assessment of tumor burden using in vivo bioluminescence imaging

    In vivo bioluminescence imaging (BLI) is a sensitive imaging modality that is rapid and accessible, and may comprise an ideal tool for evaluating tumor growth. In this study, the kinetic of tumor growth has been assessed in C26 colon carcinoma bearing BALB/c mouse model. The ability of BLI to noninvasively quantitate the growth of subcutaneous tumors transplanted with C26 cells genetically engineered to stably express firefly luciferase and herpes simplex virus type-1 thymidine kinase (C26/tk-luc). A good correlation (R 2=0.998) of photon emission to the cell number was found in vitro. Tumor burden and tumor volume were monitored in vivo over time by quantitation of photon emission using Xenogen IVIS 50 and standard external caliper measurement, respectively. At various time intervals, tumor-bearing mice were imaged to determine the correlation of in vivo BLI to tumor volume. However, a correlation of BLI to tumor volume was observed when tumor volume was smaller than 1000 mm3 (R 2=0.907). γ Scintigraphy combined with [131I]FIAU was another imaging modality used for verifying the previous results. In conclusion, this study showed that bioluminescence imaging is a powerful and quantitative tool for the direct assay to monitor tumor growth in vivo. The dual reporter genes transfected tumor-bearing animal model can be applied in the evaluation of the efficacy of new developed anti-cancer drugs

  14. Multimodal imaging of orthotopic hepatocellular carcinoma using small animal PET, bioluminescence and contrast enhanced CT imaging

    Molecular imaging with small-animal PET and bioluminescence imaging has been used as an important tool in cancer research. One of the disadvantages of these imaging modalities is the lack of anatomic information. To obtain fusion images with both molecular and anatomical information, small-animal PET and bioluminescence images fused with contrast enhance CT image in orthotopic hepatocellular carcinoma (HCC) model. We retrovially transfected dual gene (HSV1-tk and firefly luciferase) to morris hepatoma cells. The expression of HSV1-tk and luciferase was checked by optical imager and in vitro radiolabeled FIAU uptake, respectively and also checked by RT-PCR analysis. MCA-TL cells (5X105/ 0.05 ml) mixed with matrigel (1: 10) injected into left lobe of liver in nude mice. 124I-FIAU-PET, bioluminescence and contrast enhanced CT images were obtained in the orthotopic HCC model and digital whole body autoradiography (DWBA) was performed. Small animal PET image was obtained at 2 h post injection of 124I-FIAU and contrast enhanced CT image was obtained at 3 h post injection of Fenestra LC (0.3 ml). MCA-TL cells showed more specific 124I-FIAU uptake and higher luminescent activity than parental cells. The orthotopic HCC was detected by 124I-FIAU PET, contrast enhanced CT, and BLI and confirmed by DWBA. Registered image in orthotopic HCC t models showed a good correlation of images from both PET and CT. Contrast enhanced CT image delineated margin of HCC. Multimodal imaging with 124I-FIAU PET, bioluminescence and contrast enhanced CT allows a precise and improved detection of tumor in orthotopic hepatocellular carcinoma model. Multimodal imaging is potentially useful for monitoring progression of hepatic metastasis and for the evaluation of cancer treatments

  15. Effect of optical tissue clearing on spatial resolution and sensitivity of bioluminescence imaging.

    Jansen, E Duco; Pickett, Patrick M; Mackanos, Mark A; Virostko, John

    2006-01-01

    In vivo bioluminescence imaging (BLI) is a powerful method of in vivo molecular imaging based on the use of optically active luciferase reporter genes. Although this method provides superior sensitivity relative to other in vivo imaging methods, spatial resolution is poor due to light scattering. The objective of this study was to use hyperosmotic agents to reduce the scattering coefficient and hence improve spatial resolution of the BLI method. A diffusing fiber tip was used to simulate an isotropic point source of bioluminescence emission (550 to 650 nm). Mouse skin was treated in vitro and in vivo with glycerol (50%, 30 min) and measurements of optical properties, and imaging photon counts were made before, during, and after application of glycerol to the skin sample. Glycerol application to mouse skin had little effect on the absorption coefficient but reduced the reduced scattering coefficient by more than one order of magnitude. This effect was reversible. Consequently, the spot size (i.e., spatial resolution) of the bioluminescence point source imaged through the skin decreased by a factor of 2 (550-nm light) to 3 (650-nm light) after 30 min. Simultaneously, an almost twofold decrease in the amount of light detected by the BLI system was observed, despite the fact that total transmission increased 1.7 times. We have shown here that multiply scattered light is responsible for both observations. We have shown that applying a hyperosmotic clearing agent to the skin of small rodents has the potential to improve spatial resolution of BLI owing to a reduction in the reduced scattering coefficient in the skin by one order of magnitude. However, reducing the scattering coefficient reduces the amount of light reaching the camera due to a reduction in the amount of multiply scattered light that reaches the camera aperture and thus reducing the sensitivity of the method. PMID:16965147

  16. Bioluminescence imaging of leukemia cell lines in vitro and in mouse xenografts: effects of monoclonal and polyclonal cell populations on intensity and kinetics of photon emission

    Christoph Sandra; Schlegel Jennifer; Alvarez-Calderon Francesca; Kim Yong-Mi; Brandao Luis N; DeRyckere Deborah; Graham Douglas K

    2013-01-01

    Abstract Background We investigated the utility of bioluminescence imaging (BLI) using firefly luciferase in monoclonal and polyclonal populations of leukemia cells in vitro and in vivo. Methods Monoclonal and polyclonal human lymphoid and myeloid leukemia cell lines transduced with firefly luciferase were used for BLI. Results Kinetics and dynamics of bioluminescence signal were cell line dependent. Luciferase expression decreased significantly over time in polyclonal leukemia cells in vitro...

  17. Bioluminescence Imaging of Chlamydia muridarum Ascending Infection in Mice

    Campbell, Jessica; Huang, Yumeng; Liu, Yuanjun; Schenken, Robert; Arulanandam, Bernard; Zhong, Guangming

    2014-01-01

    Chlamydial pathogenicity in the upper genital tract relies on chlamydial ascending from the lower genital tract. To monitor chlamydial ascension, we engineered a luciferase-expressing C. muridarum. In cells infected with the luciferase-expressing C. muridarum, luciferase gene expression and enzymatic activity (measured as bioluminescence intensity) correlated well along the infection course, suggesting that bioluminescence can be used for monitoring chlamydial replication. Following an intrav...

  18. Let There Be Light! Bioluminescent Imaging to Study Bacterial Pathogenesis in Live Animals and Plants.

    Kassem, Issmat I; Splitter, Gary A; Miller, Sally; Rajashekara, Gireesh

    2016-01-01

    : Bioluminescence imaging (BLI) of bacteria was primarily designed to permit real-time, sensitive, and noninvasive monitoring of the progression of infection in live animals. Generally, BLI relies on the construction of bacterial strains that possess the lux operon. The lux operon is composed of a set of genes that encode the luciferase enzyme and its cognate substrate, which interact to produce light-a phenomenon that is referred to as bioluminescence. Bioluminescence emitted by the bacteria can then be detected and imaged within a living host using sensitive charge-coupled device (CCD) cameras. In comparison to traditional host-pathogen studies, BLI offers the opportunity for extended monitoring of infected animals without resorting to euthanasia and extensive tissue processing at each time point. Therefore, BLI can reduce the number of animals required to generate meaningful data, while significantly contributing to the understanding of pathogenesis in the host and, subsequently, the development and evaluation of adequate vaccines and therapeutics. BLI is also useful in characterizing the interactions of pathogens with plants and the para-host environment. In this chapter, we demonstrate the broad application of BLI for studying bacterial pathogens in different niches. Furthermore, we will specifically focus on the use of BLI to characterize the following: (1) the pathogenesis of Brucella melitensis in mice (animal host), and (2) the progression of infection of Clavibacter michiganensis subsp. michiganensis in tomatoes (plant host). These studies will provide an overview of the wide potential of BLI and its role in enhancing the study of unique-and sometimes difficult-to-characterize-bacterial pathogens. PMID:25395174

  19. Compartmentalization of algal bioluminescence: autofluorescence of bioluminescent particles in the dinoflagellate Gonyaulax as studied with image-intensified video microscopy and flow cytometry

    1985-01-01

    Compartmentalization of specialized functions to discrete locales is a fundamental theme of eucaryotic organization in cells. We report here that bioluminescence of the dinoflagellate alga Gonyaulax originates in vivo from discrete subcellular loci that are intrinsically fluorescent. We demonstrate this localization by comparing the loci of fluorescence and bioluminescence as visualized by image-intensified video microscopy. These fluorescent particles appeared to be the same as the previousl...

  20. Use of a highly sensitive two-dimensional luminescence imaging system to monitor endogenous bioluminescence in plant leaves

    Flor-Henry Michel

    2004-11-01

    Full Text Available Abstract Background All living organisms emit spontaneous low-level bioluminescence, which can be increased in response to stress. Methods for imaging this ultra-weak luminescence have previously been limited by the sensitivity of the detection systems used. Results We developed a novel configuration of a cooled charge-coupled device (CCD for 2-dimensional imaging of light emission from biological material. In this study, we imaged photon emission from plant leaves. The equipment allowed short integration times for image acquisition, providing high resolution spatial and temporal information on bioluminescence. We were able to carry out time course imaging of both delayed chlorophyll fluorescence from whole leaves, and of low level wound-induced luminescence that we showed to be localised to sites of tissue damage. We found that wound-induced luminescence was chlorophyll-dependent and was enhanced at higher temperatures. Conclusions The data gathered on plant bioluminescence illustrate that the equipment described here represents an improvement in 2-dimensional luminescence imaging technology. Using this system, we identify chlorophyll as the origin of wound-induced luminescence from leaves.

  1. Bioluminescence Imaging Reveals Dynamics of Beta Cell Loss in the Non-Obese Diabetic (NOD) Mouse Model

    Virostko, John; Radhika, Armandla; Poffenberger, Greg; Dula, Adrienne N.; Moore, Daniel J; Powers, Alvin C.

    2013-01-01

    We generated a mouse model (MIP-Luc-VU-NOD) that enables non-invasive bioluminescence imaging (BLI) of beta cell loss during the progression of autoimmune diabetes and determined the relationship between BLI and disease progression. MIP-Luc-VU-NOD mice displayed insulitis and a decline in bioluminescence with age which correlated with beta cell mass, plasma insulin, and pancreatic insulin content. Bioluminescence declined gradually in female MIP-Luc-VU-NOD mice, reaching less than 50% of the ...

  2. Functional imaging of interleukin 1 beta expression in inflammatory process using bioluminescence imaging in transgenic mice

    Liu Zhihui

    2008-08-01

    Full Text Available Abstract Background Interleukin 1 beta (IL-1β plays an important role in a number of chronic and acute inflammatory diseases. To understand the role of IL-1β in disease processes and develop an in vivo screening system for anti-inflammatory drugs, a transgenic mouse line was generated which incorporated the transgene firefly luciferase gene driven by a 4.5-kb fragment of the human IL-1β gene promoter. Luciferase gene expression was monitored in live mice under anesthesia using bioluminescence imaging in a number of inflammatory disease models. Results In a LPS-induced sepsis model, dramatic increase in luciferase activity was observed in the mice. This transgene induction was time dependent and correlated with an increase of endogenous IL-1β mRNA and pro-IL-1β protein levels in the mice. In a zymosan-induced arthritis model and an oxazolone-induced skin hypersensitivity reaction model, luciferase expression was locally induced in the zymosan injected knee joint and in the ear with oxazolone application, respectively. Dexamethasone suppressed the expression of luciferase gene both in the acute sepsis model and in the acute arthritis model. Conclusion Our data suggest that the transgenic mice model could be used to study transcriptional regulation of the IL-1β gene expression in the inflammatory process and evaluation the effect of anti-inflammatory drug in vivo.

  3. In vitro influence of hypoxia on bioluminescence imaging in brain tumor cells

    Moriyama, Eduardo H.; Jarvi, Mark; Niedre, Mark; Mocanu, Joseph D.; Moriyama, Yumi; Li, Buhong; Lilge, Lothar; Wilson, Brian C.

    2007-02-01

    Bioluminescence Imaging (BLI) has been employed as an imaging modality to identify and characterize fundamental processes related to cancer development and response at cellular and molecular levels. This technique is based on the reaction of luciferin with oxygen in the presence of luciferase and ATP. A major concern in this technique is that tumors are generally hypoxic, either constitutively and/or as a result of treatment, therefore the oxygen available for the bioluminescence reaction could possibly be reduced to limiting levels, and thus leading to underestimation of the actual number of luciferase-labeled cells during in vivo procedures. In this report, we present the initial in vitro results of the oxygen dependence of the bioluminescence signal in rat gliosarcoma 9L cells tagged with the luciferase gene (9L luc cells). Bioluminescence photon emission from cells exposed to different oxygen tensions was detected by a sensitive CCD camera upon exposure to luciferin. The results showed that bioluminescence signal decreased at administered pO II levels below about 5%, falling by approximately 50% at 0.2% pO II. Additional experiments showed that changes in BLI was due to the cell inability to maintain normal levels of ATP during the hypoxic period reducing the ATP concentration to limiting levels for BLI.

  4. Bioluminescence imaging to monitor the prolongation of stem cell survival by pharmaceutical intervention

    The rapid donor cell death and rejection owing to humoral and cellular immune reactions are a basic limitation encountered in stem cell therapy for treatment of cardiovascular disease. We investigated the potential for longitudinal bioluminescence imaging to monitor the survival of transplanted stem cells prolonged by immunosuppressive agents. Embryonic rat H9c2 cardio myoblasts were transfected with adenovirus containing luciferase reporter gene (Ad-CMV-Fluc) in different MOI (1,10,100) and various cell doses (1x105 - 5x106)followed by injection in the thigh muscle of nude mice (n=6 per group), Other mice (n = 18) were undergone transient immunosuppression provided by either Cyclosporine (5mg/kg) or Tacrolimus (1mg/kg) or Dexamethasone (4mg/kg) beginning 3 days prior to and continuing to 2 weeks after transplantation. Optical bioluminescent imaging was then daily carried out using cooled CCD camera (Xenogen) Viral transfection at MOI 100 and the 5x106 cell dose implantation resulted in optimal transgene efficiency. Mice received immunosuppressive agents displayed long-term in vivo reporter gene expression for a time course of 14 days. Tacrolimus (Prograf) and Cyclosporine successfully suppressed the transplanted cell loss in animals, that obviously observed until day 8 as compared to Dexamethasone-treated and non-treated mice (day 1: 1.00E+08 (Prograf), 9.47E+07 (Cys), 5.25E+07 (Dex), and 1.25E+07 p/s/cm2/sr (control); day 8: 3.27E+05 (Prograf), 1.02E+05 (Cys), 6.17E+04 (Dex) and 2.73E+04 p/s/cm2/sr (control)) and continued expressing bioluminescence until day 13 ( 6.42E+05 (Prograf), 4.99E+05 (Cys), and 4.10E+04 p/s/cm2/sr. Induction of immune tolerance using pharmaceutical agents during cardio myoblast transplantation improved long-term donor cell survival in murine muscles. Optical imaging technique is capable of being used for tracking implanted stem cells in myocardium of living subjects over time

  5. Evaluation of biolistic gene transfer methods in vivo using non-invasive bioluminescent imaging techniques

    Daniell Henry

    2011-06-01

    Full Text Available Abstract Background Gene therapy continues to hold great potential for treating many different types of disease and dysfunction. Safe and efficient techniques for gene transfer and expression in vivo are needed to enable gene therapeutic strategies to be effective in patients. Currently, the most commonly used methods employ replication-defective viral vectors for gene transfer, while physical gene transfer methods such as biolistic-mediated ("gene-gun" delivery to target tissues have not been as extensively explored. In the present study, we evaluated the efficacy of biolistic gene transfer techniques in vivo using non-invasive bioluminescent imaging (BLI methods. Results Plasmid DNA carrying the firefly luciferase (LUC reporter gene under the control of the human Cytomegalovirus (CMV promoter/enhancer was transfected into mouse skin and liver using biolistic methods. The plasmids were coupled to gold microspheres (1 μm diameter using different DNA Loading Ratios (DLRs, and "shot" into target tissues using a helium-driven gene gun. The optimal DLR was found to be in the range of 4-10. Bioluminescence was measured using an In Vivo Imaging System (IVIS-50 at various time-points following transfer. Biolistic gene transfer to mouse skin produced peak reporter gene expression one day after transfer. Expression remained detectable through four days, but declined to undetectable levels by six days following gene transfer. Maximum depth of tissue penetration following biolistic transfer to abdominal skin was 200-300 μm. Similarly, biolistic gene transfer to mouse liver in vivo also produced peak early expression followed by a decline over time. In contrast to skin, however, liver expression of the reporter gene was relatively stable 4-8 days post-biolistic gene transfer, and remained detectable for nearly two weeks. Conclusions The use of bioluminescence imaging techniques enabled efficient evaluation of reporter gene expression in vivo. Our results demonstrate that different tissues show different expression kinetics following gene transfer of the same reporter plasmid to different mouse tissues in vivo. We evaluated superficial (skin and abdominal organ (liver targets, and found that reporter gene expression peaked within the first two days post-transfer in each case, but declined most rapidly in the skin (3-4 days compared to liver (10-14 days. This information is essential for designing effective gene therapy strategies in different target tissues.

  6. Bioluminescence imaging to monitor the prolongation of stem cell survival by pharmaceutical intervention

    Le, Uyenchi N.; Min, Jung Joon; Moon, Sung Min; Ahn, Young Keun; Kim, Yong Sook; Joo, Soo Yeon; Hong, Moon Hwa; Jeong, Myung Ho; Song, Ho Cheon; Bom, Hee Seung [Chonnam National University Medical School, Gwangju (Korea, Republic of)

    2005-07-01

    The rapid donor cell death and rejection owing to humoral and cellular immune reactions are a basic limitation encountered in stem cell therapy for treatment of cardiovascular disease. We investigated the potential for longitudinal bioluminescence imaging to monitor the survival of transplanted stem cells prolonged by immunosuppressive agents. Embryonic rat H9c2 cardio myoblasts were transfected with adenovirus containing luciferase reporter gene (Ad-CMV-Fluc) in different MOI (1,10,100) and various cell doses (1x10{sup 5} - 5x10{sup 6})followed by injection in the thigh muscle of nude mice (n=6 per group), Other mice (n = 18) were undergone transient immunosuppression provided by either Cyclosporine (5mg/kg) or Tacrolimus (1mg/kg) or Dexamethasone (4mg/kg) beginning 3 days prior to and continuing to 2 weeks after transplantation. Optical bioluminescent imaging was then daily carried out using cooled CCD camera (Xenogen) Viral transfection at MOI 100 and the 5x10{sup 6} cell dose implantation resulted in optimal transgene efficiency. Mice received immunosuppressive agents displayed long-term in vivo reporter gene expression for a time course of 14 days. Tacrolimus (Prograf) and Cyclosporine successfully suppressed the transplanted cell loss in animals, that obviously observed until day 8 as compared to Dexamethasone-treated and non-treated mice (day 1: 1.00E+08 (Prograf), 9.47E+07 (Cys), 5.25E+07 (Dex), and 1.25E+07 p/s/cm{sup 2}/sr (control); day 8: 3.27E+05 (Prograf), 1.02E+05 (Cys), 6.17E+04 (Dex) and 2.73E+04 p/s/cm{sup 2}/sr (control)) and continued expressing bioluminescence until day 13 ( 6.42E+05 (Prograf), 4.99E+05 (Cys), and 4.10E+04 p/s/cm{sup 2}/sr. Induction of immune tolerance using pharmaceutical agents during cardio myoblast transplantation improved long-term donor cell survival in murine muscles. Optical imaging technique is capable of being used for tracking implanted stem cells in myocardium of living subjects over time.

  7. Bioluminescence in vivo imaging of autoimmune encephalomyelitis predicts disease

    Steinman Lawrence; Ho Peggy; Luo Jian; Wyss-Coray Tony

    2008-01-01

    Abstract Background Experimental autoimmune encephalomyelitis is a widely used animal model to understand not only multiple sclerosis but also basic principles of immunity. The disease is scored typically by observing signs of paralysis, which do not always correspond with pathological changes. Methods Experimental autoimmune encephalomyelitis was induced in transgenic mice expressing an injury responsive luciferase reporter in astrocytes (GFAP-luc). Bioluminescence in the brain and spinal co...

  8. Development of Optical Molecular Imaging System for the Acquisition of Bioluminescence Signals from Small Animals

    Optical imaging is providing great advance and improvement in genetic and molecular imaging of animals and humans. Optical imaging system consists of optical imaging devices, which carry out major function for monitoring, tracing, and imaging in most of molecular in-vivo researches. In bio-luminescent imaging, small animals containing luciferase gene locally irradiate light, and emitted photons transmitted through skin of the small animals are imaged by using a high sensitive charged coupled device (CCD) camera. In this paper, we introduced optical imaging system for the image acquisition of bio-luminescent signals emitted from small animals. In the system, Nikon lens and four LED light sources were mounted at the inside of a dark box. A cooled CCD camera equipped with a control module was used. We tested the performance of the optical imaging system using effendorf tube and light emitting bacteria which injected intravenously into CT26 tumor bearing nude mouse. The performance of implemented optical imaging system for bio-luminescence imaging was demonstrated and the feasibility of the system in small animal imaging application was proved. We anticipate this system could be a useful tool for the molecular imaging of small animals adaptable for various experimental conditions in future

  9. Development of Optical Molecular Imaging System for the Acquisition of Bioluminescence Signals from Small Animals

    Lee, Byeong Il; Kim, Hyeon Sik; Jeong, Hye Jin; Lee, Hyung Jae; Moon, Seung Min; Kwon, Seung Young; Jeong, Shin Young; Bom, Hee Seung; Min, Jung Joon [Chonnam National University Hospital, Gwangju (Korea, Republic of); Choi, Eun Seo [Chosun University, Gwangju (Korea, Republic of)

    2009-08-15

    Optical imaging is providing great advance and improvement in genetic and molecular imaging of animals and humans. Optical imaging system consists of optical imaging devices, which carry out major function for monitoring, tracing, and imaging in most of molecular in-vivo researches. In bio-luminescent imaging, small animals containing luciferase gene locally irradiate light, and emitted photons transmitted through skin of the small animals are imaged by using a high sensitive charged coupled device (CCD) camera. In this paper, we introduced optical imaging system for the image acquisition of bio-luminescent signals emitted from small animals. In the system, Nikon lens and four LED light sources were mounted at the inside of a dark box. A cooled CCD camera equipped with a control module was used. We tested the performance of the optical imaging system using effendorf tube and light emitting bacteria which injected intravenously into CT26 tumor bearing nude mouse. The performance of implemented optical imaging system for bio-luminescence imaging was demonstrated and the feasibility of the system in small animal imaging application was proved. We anticipate this system could be a useful tool for the molecular imaging of small animals adaptable for various experimental conditions in future

  10. Bioluminescence imaging of chondrocytes in rabbits by intraarticular injection of D-luciferin

    Luciferase is one of the most commonly used reporter enzymes in the field of in vivo optical imaging. D-luciferin, the substrate for firefly luciferase has very high cost that allows this kind of experiment limited to small animals such as mice and rats. In this current study, we validated local injection of D-luciferin in the articular capsule for bioluminescence imaging in rabbits. Chondrocytes were cultured and infected by replication-defective adenoviral vector encoding firefly luciferase (Fluc). Chondrocytes expressing Fluc were injected or implanted in the left knee joint. The rabbits underwent optical imaging studies after local injection of D-luciferin at 1, 5, 7, 9 days after cellular administration. We sought whether optimal imaging signals was could be by a cooled CCD camera after local injection of D-luciferin. Imaging signal was not observed from the left knee joint after intraperitoneal injection of D-luciferin (15 mg/kg), whereas it was observed after intraarticular injection. Photon intensity from the left knee joint of rabbits was compared between cell injected and implanted groups after intraarticular injection of D-luciferin. During the period of imaging studies, photon intensity of the cell implanted group was 5-10 times higher than that of the cell injected group. We successfully imaged chondrocytes expressing Fluc after intraarticular injection of D-luciferin. This technique may be further applied to develop new drugs for knee joint disease

  11. Uptake kinetics and biodistribution of 14C-d-luciferin - a radiolabeled substrate for the firefly luciferase catalyzed bioluminescence reaction: impact on bioluminescence based reporter gene imaging

    Firefly luciferase catalyzes the oxidative decarboxylation of d-luciferin to oxyluciferin in the presence of cofactors, producing bioluminescence. This reaction is used in optical bioluminescence-based molecular imaging approaches to detect the expression of the firefly luciferase reporter gene. Biokinetics and distribution of the substrate most likely have a significant impact on levels of light signal and therefore need to be investigated. Benzene ring 14C(U)-labeled d-luciferin was utilized. Cell uptake and efflux assays, murine biodistribution, autoradiography and CCD-camera based optical bioluminescence imaging were carried out to examine the in vitro and in vivo characteristics of the tracer in cell culture and in living mice respectively. Radiolabeled and unlabeled d-luciferin revealed comparable levels of light emission when incubated with equivalent amounts of the firefly luciferase enzyme. Cell uptake assays in pCMV-luciferase-transfected cells showed slow trapping of the tracer and relatively low uptake values (up to 22.9-fold higher in firefly luciferase gene-transfected vs. nontransfected cells, p=0.0002). Biodistribution studies in living mice after tail-vein injection of 14C-d-luciferin demonstrated inhomogeneous tracer distribution with early predominant high radioactivity levels in kidneys (10.6% injected dose [ID]/g) and liver (11.9% ID/g), followed at later time points by the bladder (up to 81.3% ID/g) and small intestine (6.5% ID/g), reflecting the elimination routes of the tracer. Kinetics and uptake levels profoundly differed when using alternate injection routes (intravenous versus intraperitoneal). No clear trapping of 14C-d-luciferin in firefly luciferase-expressing tissues could be observed in vivo. The data obtained with 14C-d-luciferin provide insights into the dynamics of d-luciferin cell uptake, intracellular accumulation, and efflux. Results of the biodistribution and autoradiographic studies should be useful for optimizing and adapting optical imaging protocols to specific experimental settings when utilizing the firefly luciferase and d-luciferin system. (orig.)

  12. Rapid and Quantitative Assessment of Cancer Treatment Response Using In Vivo Bioluminescence Imaging

    Alnawaz Rehemtulla

    2000-01-01

    Full Text Available Current assessment of orthotopic tumor models in animals utilizes survival as the primary therapeutic end point. In vivo bioluminescence imaging (BLI is a sensitive imaging modality that is rapid and accessible, and may comprise an ideal tool for evaluating antineoplastic therapies [1 ]. Using human tumor cell lines constitutively expressing luciferase, the kinetics of tumor growth and response to therapy have been assessed in intraperitoneal [2], subcutaneous, and intravascular [3] cancer models. However, use of this approach for evaluating orthotopic tumor models has not been demonstrated. In this report, the ability of BLI to noninvasively quantitate the growth and therapeuticinduced cell kill of orthotopic rat brain tumors derived from 9L gliosarcoma cells genetically engineered to stably express firefly luciferase (9LLuc was investigated. Intracerebral tumor burden was monitored over time by quantitation of photon emission and tumor volume using a cryogenically cooled CCD camera and magnetic resonance imaging (MRI, respectively. There was excellent correlation (r=0.91 between detected photons and tumor volume. A quantitative comparison of tumor cell kill determined from serial MRI volume measurements and BLI photon counts following 1,3-bis(2-chloroethyl-1-nitrosourea (BCNU treatment revealed that both imaging modalities yielded statistically similar cell kill values (P=.951. These results provide direct validation of BLI imaging as a powerful and quantitative tool for the assessment of antineoplastic therapies in living animals.

  13. Bioluminescent imaging: a critical tool in pre-clinical oncology research.

    O'Neill, Karen

    2010-02-01

    Bioluminescent imaging (BLI) is a non-invasive imaging modality widely used in the field of pre-clinical oncology research. Imaging of small animal tumour models using BLI involves the generation of light by luciferase-expressing cells in the animal following administration of substrate. This light may be imaged using an external detector. The technique allows a variety of tumour-associated properties to be visualized dynamically in living models. The increasing use of BLI as a small-animal imaging modality has led to advances in the development of xenogeneic, orthotopic, and genetically engineered animal models expressing luciferase genes. This review aims to provide insight into the principles of BLI and its applications in cancer research. Many studies to assess tumour growth and development, as well as efficacy of candidate therapeutics, have been performed using BLI. More recently, advances have also been made using bioluminescent imaging in studies of protein-protein interactions, genetic screening, cell-cycle regulators, and spontaneous cancer development. Such novel studies highlight the versatility and potential of bioluminescent imaging in future oncological research.

  14. Non-invasive visualisation of the development of peritoneal carcinomatosis and tumour regression after 213Bi-radioimmunotherapy using bioluminescence imaging

    Non-invasive imaging of tumour development remains a challenge, especially for tumours in the intraperitoneal cavity. Therefore, the aim of this study was the visualisation of both the development of peritoneal carcinomatosis and tumour regression after radioimmunotherapy with tumour-specific 213Bi-Immunoconjugates, via in vivo bioluminescence imaging of firefly luciferase-transfected cells. Human diffuse-type gastric cancer cells expressing mutant d9-E-cadherin were stably transfected with firefly luciferase (HSC45-M2-luc). For bioluminescence imaging, nude mice were inoculated intraperitoneally with 1 x 107 HSC45-M2-luc cells. On days 4 and 8 after tumour cell inoculation, imaging was performed following D-luciferin injection using a cooled CCD camera with an image intensifier unit. For therapy, mice were injected with 2.7 MBq 213Bi-d9MAb targeting d9-E-cadherin on day 8 after tumour cell inoculation. Bioluminescence images were taken every 4 days to monitor tumour development. After i.p. inoculation of HSC45-M2-luc cells into nude mice, development as well as localisation of peritoneal carcinomatosis could be visualised using bioluminescence imaging. Following 213Bi-d9MAb therapy on day 8 after intraperitoneal inoculation of HSC45-M2-luc cells, small tumour nodules were totally eliminated and larger nodules showed a clear reduction in size on day 12 after tumour cell inoculation. Subsequently a recurrence of tumour mass was observed, starting from the remaining tumour spots. By measuring the mean grey level intensity, tumour development over time could be demonstrated. Non-invasive bioluminescence imaging permits visualisation of the development of peritoneal carcinomatosis, localisation of tumour in the intraperitoneal cavity and evaluation of therapeutic success after 213Bi-d9MAb treatment. (orig.)

  15. In vivo bioluminescence imaging study to monitor ectopic bone formation by luciferase gene marked mesenchymal stem cells

    Olivo, C.; Alblas, J; Verweij, V.G.M.; van Zonneveld, A.J.; Dhert, W.J.A.; Martens, A.C.M.

    2008-01-01

    Mesenchymal stem cells (MSCs) represent a powerful tool for applications in regenerative medicine. In this study, we used in vivo bioluminescence imaging to noninvasively investigate the fate and the contribution to bone formation of adult MSCs in tissue engineered constructs. Goat MSCs expressing GFP-luciferase were seeded on ceramic scaffolds and implanted subcutaneously in immune-deficient mice. The constructs were monitored weekly with bioluminescence imaging and were retrieved after 7 we...

  16. Design and development of high bioluminescent resonance energy transfer efficiency hybrid-imaging constructs.

    Kumar, Manoj; Kovalski, Letícia; Broyles, David; Hunt, Eric A; Daftarian, Pirouz; Dikici, Emre; Daunert, Sylvia; Deo, Sapna K

    2016-04-01

    Here we describe the design and construction of an imaging construct with high bioluminescent resonance energy transfer (BRET) efficiency that is composed of multiple quantum dots (QDs; λem = 655 nm) self-assembled onto a bioluminescent protein, Renilla luciferase (Rluc). This is facilitated by the streptavidin-biotin interaction, allowing the facile formation of a hybrid-imaging construct (HIC) comprising up to six QDs (acceptor) grafted onto a light-emitting Rluc (donor) core. The resulting assembly of multiple acceptors surrounding a donor permits this construct to exhibit high resonance energy transfer efficiency (∼64.8%). The HIC was characterized using fluorescence excitation anisotropy measurements and high-resolution transmission electron microscopy. To demonstrate the application of our construct, a generation-5 (G5) polyamidoamine dendrimer (PAMAM) nanocarrier was loaded with our HIC for in vitro and in vivo imaging. We envision that this design of multiple acceptors and bioluminescent donor will lead to the development of new BRET-based systems useful in sensing, imaging, and other bioanalytical applications. PMID:26772160

  17. Quantitative bioluminescence imaging of transgene expression in intact porcine antral follicles in vitro

    Jung, Song-Yi; Willard, Scott T

    2014-01-01

    Background The porcine oocyte maturation in vivo occurs within the ovarian follicle and is regulated by the interactions between oocytes and surrounding follicular components, including theca, granulosa, and cumulus cells, and follicular fluid. Therefore, the antral follicle is an essential microenvironment for efficient oocyte maturation and its developmental competence. Quantitative bioluminescence imaging of firefly luciferase reporter genes in an intact antral follicle would allow investi...

  18. Design and Synthesis of an Alkynyl Luciferin Analogue for Bioluminescence Imaging.

    Steinhardt, Rachel C; O'Neill, Jessica M; Rathbun, Colin M; McCutcheon, David C; Paley, Miranda A; Prescher, Jennifer A

    2016-03-01

    Herein, the synthesis and characterization of an alkyne-modified luciferin is reported. This bioluminescent probe was accessed using C-H activation methodology and was found to be stable in solution and capable of light production with firefly luciferase. The luciferin analogue was also cell permeant and emitted more redshifted light than d-luciferin, the native luciferase substrate. Based on these features, the alkynyl luciferin will be useful for a variety of imaging applications. PMID:26784889

  19. Construction of a bioluminescence reporter plasmid for Francisella tularensis

    Bina, Xiaowen R.; Miller, Mark A.; Bina, James E.

    2010-01-01

    A Francisella tularensis shuttle vector that constitutively expresses the Photorhabdus luminescens lux operon in type A and type B strains of F. tularensis was constructed. The bioluminescence reporter plasmid was introduced into the live vaccine strain of F. tularensis and used to follow F. tularensis growth in a murine intranasal challenge model in real time by bioluminescence imaging. The results show that the new bioluminescence reporter plasmid represents a useful tool for tularemia rese...

  20. Firefly Luciferase Mutants Allow Substrate-Selective Bioluminescence Imaging in the Mouse Brain.

    Adams, Spencer T; Mofford, David M; Reddy, G S Kiran Kumar; Miller, Stephen C

    2016-04-11

    Bioluminescence imaging is a powerful approach for visualizing specific events occurring inside live mice. Animals can be made to glow in response to the expression of a gene, the activity of an enzyme, or the growth of a tumor. But bioluminescence requires the interaction of a luciferase enzyme with a small-molecule luciferin, and its scope has been limited by the mere handful of natural combinations. Herein, we show that mutants of firefly luciferase can discriminate between natural and synthetic substrates in the brains of live mice. When using adeno-associated viral (AAV) vectors to express luciferases in the brain, we found that mutant luciferases that are inactive or weakly active with d-luciferin can light up brightly when treated with the aminoluciferins CycLuc1 and CycLuc2 or their respective FAAH-sensitive luciferin amides. Further development of selective luciferases promises to expand the power of bioluminescence and allow multiple events to be imaged in the same live animal. PMID:26991209

  1. Investigating real-time activation of adenosine receptors by bioluminescence resonance energy transfer technique

    Huang, Yimei; Yang, Hongqin; Zheng, Liqin; Chen, Jiangxu; Wang, Yuhua; Li, Hui; Xie, Shusen

    2013-02-01

    Adenosine receptors play important roles in many physiological and pathological processes, for example regulating myocardial oxygen consumption and the release of neurotransmitters. The activations of adenosine receptors have been studied by some kinds of techniques, such as western blot, immunohistochemistry, etc. However, these techniques cannot reveal the dynamical response of adenosine receptors under stimulation. In this paper, bioluminescence resonance energy transfer technique was introduced to study the real-time activation of adenosine receptors by monitoring the dynamics of cyclic adenosine monophosphate (cAMP) level. The results showed that there were significant differences between adenosine receptors on real-time responses under stimulation. Moreover, the dynamics of cAMP level demonstrated that competition between adenosine receptors existed. Taken together, our study indicates that monitoring the dynamics of cAMP level using bioluminescence resonance energy transfer technique could be one potential approach to investigate the mechanism of competitions between adenosine receptors.

  2. Bioluminescence imaging in a medium-sized animal by local injection of d-luciferin

    Luciferase is one of the most commonly used reporter enzymes in the field of molecular imaging. D-luciferin is known as the substrate for luciferase enzyme and its cost is very expensive. Therefore, the bioluminescence molecular imaging study has been allowed in small animals such as mice and rats. In this current study, we validated local injection of D-luciferin in articular capsule for bioluminescence imaging in rabbits. Chondrocytes were cultured and infected by replication-defective adenoviral vector encoding firefly luciferase. And then was performed different method of chondrocyte cell injection and transplantation into the knee of rabbits. The rabbits underwent imaging by cooled CCD camera after local injection of D-luciferin (3mg) into experimental knee joint as well as contralateral normal knee joint on days 1, 5, 7, 9. We sought whether optimal imaging signal was acquired by using cooled CCD camera after local injection of D-luciferin. We successfully visualized injected or transplanted cells in knee joint by local injection of D-luciferin. Total photon flux (7.86E+08 p/s/cm2/sr) from the knee joint transplanted with cells approximately increased 10-fold more than (9.43E+07p/s/cm2/sr) that from injected knee joints until 7 day. Imaging signal was observed in transplanted joints until day 9 after surgery while signal from injected knee was observed by day 7 after injection. We successfully carried out bioluminescence imaging study with medium sized animal by local injection of small amount of D-luciferin. Survival of chondrocytes were prolonged when surgically transplanted in joints than when directly injected in joint space

  3. Bioluminescence imaging of leukemia cell lines in vitro and in mouse xenografts: effects of monoclonal and polyclonal cell populations on intensity and kinetics of photon emission

    Christoph Sandra

    2013-01-01

    Full Text Available Abstract Background We investigated the utility of bioluminescence imaging (BLI using firefly luciferase in monoclonal and polyclonal populations of leukemia cells in vitro and in vivo. Methods Monoclonal and polyclonal human lymphoid and myeloid leukemia cell lines transduced with firefly luciferase were used for BLI. Results Kinetics and dynamics of bioluminescence signal were cell line dependent. Luciferase expression decreased significantly over time in polyclonal leukemia cells in vitro. Transplantation of polyclonal luciferase-tagged cells in mice resulted in inconsistent signal intensity. After selection of monoclonal cell populations, luciferase activity was stable, equal kinetic and dynamic of bioluminescence intensity and strong correlation between cell number and light emission in vitro were observed. We obtained an equal development of leukemia burden detected by luciferase activity in NOD-scid-gamma mice after transplantation of monoclonal populations. Conclusion The use of monoclonal leukemia cells selected for stable and equal luciferase activity is recommended for experiments in vitro and xenograft mouse models. The findings are highly significant for bioluminescence imaging focused on pre-clinical drug development.

  4. Engineering Influenza A/WSN/33 for In vivo Bioluminescent Imaging

    Lingaraju, Chetan Raj

    2014-01-01

    Influenza A virus is a major causative agent of respiratory diseases in humans. It causes significant morbidity, mortality and economic losses each year worldwide with about 3-5 million clinical infections per annum. Its ability to mutate rapidly leads to seasonal epidemics and with its high frequency of genetic reassortment it causes pandemics. Conventional methods of studying viral pathogenesis do not allow for monitoring viral spread in real time during an infection. Whole body bioluminesc...

  5. Bioluminescent imaging of ABCG2 efflux activity at the blood-placenta barrier

    Kumar, Jeyan S.; Wei, Bih-Rong; Madigan, James P.; Simpson, R. Mark; Hall, Matthew D.; Gottesman, Michael M.

    2016-01-01

    Physiologic barriers such as the blood placenta barrier (BPB) and the blood brain barrier protect the underlying parenchyma from pathogens and toxins. ATP-binding cassette (ABC) transporters are transmembrane proteins found at these barriers, and function to efflux xenobiotics and maintain chemical homeostasis. Despite the plethora of ex vivo and in vitro data showing the function and expression of ABC transporters, no imaging modality exists to study ABC transporter activity in vivo at the BPB. In the present study, we show that in vitro models of the placenta possess ABCG2 activity and can specifically transport D-luciferin, the endogenous substrate of firefly luciferase. To test ABCG2 transport activity at the BPB, we devised a breeding strategy to generate a bioluminescent pregnant mouse model to demonstrate transporter function in vivo. We found that coadministering the ABCG2 inhibitors Ko143 and gefitinib with D-luciferin increased bioluminescent signal from fetuses and placentae, whereas the control P-gp inhibitor DCPQ had no effect. We believe that our bioluminescent pregnant mouse model will facilitate greater understanding of the BPB and ABCG2 activity in health and disease. PMID:26853103

  6. Tomographic bioluminescence imaging by use of a combined optical-PET (OPET) system: a computer simulation feasibility study

    The feasibility and limits in performing tomographic bioluminescence imaging with a combined optical-PET (OPET) system were explored by simulating its image formation process. A micro-MRI based virtual mouse phantom was assigned appropriate tissue optical properties to each of its segmented internal organs at wavelengths spanning the emission spectrum of the firefly luciferase at 37 deg. C. The TOAST finite-element code was employed to simulate the diffuse transport of photons emitted from bioluminescence sources in the mouse. OPET measurements were simulated for single-point, two-point and distributed bioluminescence sources located in different organs such as the liver, the kidneys and the gut. An expectation maximization code was employed to recover the intensity and location of these simulated sources. It was found that spectrally resolved measurements were necessary in order to perform tomographic bioluminescence imaging. The true location of emission sources could be recovered if the mouse background optical properties were known a priori. The assumption of a homogeneous optical property background proved inadequate for describing photon transport in optically heterogeneous tissues and led to inaccurate source localization in the reconstructed images. The simulation results pointed out specific methodological challenges that need to be addressed before a practical implementation of OPET-based bioluminescence tomography is achieved

  7. Quantification of bioluminescence images of point source objects using diffusion theory models

    A simple approach for estimating the location and power of a bioluminescent point source inside tissue is reported. The strategy consists of using a diffuse reflectance image at the emission wavelength to determine the optical properties of the tissue. Following this, bioluminescence images are modelled using a single point source and the optical properties from the reflectance image, and the depth and power are iteratively adjusted to find the best agreement with the experimental image. The forward models for light propagation are based on the diffusion approximation, with appropriate boundary conditions. The method was tested using Monte Carlo simulations, Intralipid tissue-simulating phantoms and ex vivo chicken muscle. Monte Carlo data showed that depth could be recovered within 6% for depth 4-12 mm, and the corresponding relative source power within 12%. In Intralipid, the depth could be estimated within 8% for depth 4-12 mm, and the relative source power, within 20%. For ex vivo tissue samples, source depths of 4.5 and 10 mm and their relative powers were correctly identified

  8. Accounting for systematic errors in bioluminescence imaging to improve quantitative accuracy

    Taylor, Shelley L.; Perry, Tracey A.; Styles, Iain B.; Cobbold, Mark; Dehghani, Hamid

    2015-07-01

    Bioluminescence imaging (BLI) is a widely used pre-clinical imaging technique, but there are a number of limitations to its quantitative accuracy. This work uses an animal model to demonstrate some significant limitations of BLI and presents processing methods and algorithms which overcome these limitations, increasing the quantitative accuracy of the technique. The position of the imaging subject and source depth are both shown to affect the measured luminescence intensity. Free Space Modelling is used to eliminate the systematic error due to the camera/subject geometry, removing the dependence of luminescence intensity on animal position. Bioluminescence tomography (BLT) is then used to provide additional information about the depth and intensity of the source. A substantial limitation in the number of sources identified using BLI is also presented. It is shown that when a given source is at a significant depth, it can appear as multiple sources when imaged using BLI, while the use of BLT recovers the true number of sources present.

  9. Intracranial implantation with subsequent 3D in vivo bioluminescent imaging of murine gliomas.

    Abdelwahab, Mohammed G; Sankar, Tejas; Preul, Mark C; Scheck, Adrienne C

    2011-01-01

    The mouse glioma 261 (GL261) is recognized as an in vivo model system that recapitulates many of the features of human glioblastoma multiforme (GBM). The cell line was originally induced by intracranial injection of 3-methyl-cholantrene into a C57BL/6 syngeneic mouse strain (1); therefore, immunologically competent C57BL/6 mice can be used. While we use GL261, the following protocol can be used for the implantation and monitoring of any intracranial mouse tumor model. GL261 cells were engineered to stably express firefly luciferase (GL261-luc). We also created the brighter GL261-luc2 cell line by stable transfection of the luc2 gene expressed from the CMV promoter. C57BL/6-cBrd/cBrd/Cr mice (albino variant of C57BL/6) from the National Cancer Institute, Frederick, MD were used to eliminate the light attenuation caused by black skin and fur. With the use of albino C57BL/6 mice; in vivo imaging using the IVIS Spectrum in vivo imaging system is possible from the day of implantation (Caliper Life Sciences, Hopkinton, MA). The GL261-luc and GL261-luc2 cell lines showed the same in vivo behavior as the parental GL261 cells. Some of the shared histological features present in human GBMs and this mouse model include: tumor necrosis, pseudopalisades, neovascularization, invasion, hypercellularity, and inflammation (1). Prior to implantation animals were anesthetized by an intraperitoneal injection of ketamine (50 mg/kg), xylazine (5 mg/kg) and buprenorphine (0.05 mg/kg), placed in a stereotactic apparatus and an incision was made with a scalpel over the cranial midline. A burrhole was made 0.1 mm posterior to the bregma and 2.3mm to the right of the midline. A needle was inserted to a depth of 3mm and withdrawn 0.4 mm to a depth of 2.6 mm. Two μl of GL261-luc or GL261-luc2 cells (10(7) cells/ml) were infused over the course of 3 minutes. The burrhole was closed with bonewax and the incision was sutured. Following stereotactic implantation the bioluminescent cells are detectable from the day of implantation and the tumor can be analyzed using the 3D image reconstruction feature of the IVIS Spectrum instrument. Animals receive a subcutaneous injection of 150 μg luciferin /kg body weight 20 min prior to imaging. Tumor burden is quantified using mean tumor bioluminescence over time. Tumor-bearing mice were observed daily to assess morbidity and were euthanized when one or more of the following symptoms are present: lethargy, failure to ambulate, hunched posture, failure to groom, anorexia resulting in >10% loss of weight. Tumors were evident in all of the animals on necropsy. PMID:22158303

  10. In Vivo Bioluminescent Imaging (BLI: Noninvasive Visualization and Interrogation of Biological Processes in Living Animals

    Steven Ripp

    2010-12-01

    Full Text Available In vivo bioluminescent imaging (BLI is increasingly being utilized as a method for modern biological research. This process, which involves the noninvasive interrogation of living animals using light emitted from luciferase-expressing bioreporter cells, has been applied to study a wide range of biomolecular functions such as gene function, drug discovery and development, cellular trafficking, protein-protein interactions, and especially tumorigenesis, cancer treatment, and disease progression. This article will review the various bioreporter/biosensor integrations of BLI and discuss how BLI is being applied towards a new visual understanding of biological processes within the living organism.

  11. Remote detection of human toxicants in real time using a human-optimized, bioluminescent bacterial luciferase gene cassette bioreporter

    Close, Dan; Webb, James; Ripp, Steven; Patterson, Stacey; Sayler, Gary

    2012-06-01

    Traditionally, human toxicant bioavailability screening has been forced to proceed in either a high throughput fashion using prokaryotic or lower eukaryotic targets with minimal applicability to humans, or in a more expensive, lower throughput manner that uses fluorescent or bioluminescent human cells to directly provide human bioavailability data. While these efforts are often sufficient for basic scientific research, they prevent the rapid and remote identification of potentially toxic chemicals required for modern biosecurity applications. To merge the advantages of high throughput, low cost screening regimens with the direct bioavailability assessment of human cell line use, we re-engineered the bioluminescent bacterial luciferase gene cassette to function autonomously (without exogenous stimulation) within human cells. Optimized cassette expression provides for fully endogenous bioluminescent production, allowing continuous, real time monitoring of the bioavailability and toxicology of various compounds in an automated fashion. To access the functionality of this system, two sets of bioluminescent human cells were developed. The first was programed to suspend bioluminescent production upon toxicological challenge to mimic the non-specific detection of a toxicant. The second induced bioluminescence upon detection of a specific compound to demonstrate autonomous remote target identification. These cells were capable of responding to μM concentrations of the toxicant n-decanal, and allowed for continuous monitoring of cellular health throughout the treatment process. Induced bioluminescence was generated through treatment with doxycycline and was detectable upon dosage at a 100 ng/ml concentration. These results demonstrate that leveraging autonomous bioluminescence allows for low-cost, high throughput direct assessment of toxicant bioavailability.

  12. 18F-fluoride PET imaging in a nude rat model of bone metastasis from breast cancer: Comparison with 18F-FDG and bioluminescence imaging

    Introduction: Clinically-relevant animal models and appropriate imaging diagnostic tools are essential to study cancer and develop novel therapeutics. We evaluated a model of bone metastasis in nude rats by micro-PET and bioluminescence imaging. Methods: A bone metastasis model was produced by intracardiac injection of osteotropic MDA-MB-231Bo-Luc human breast cancer cells into nude rats. Bioluminescence imaging and micro-PET scans using 18F-FDG and 18F-fluoride were acquired serially for 5 weeks. We correlated bioluminescence imaging, 18F-FDG and 18F-fluoride PET images, and histological slides. Results: Multiple bone metastases were successfully evaluated by bioluminescence imaging and 18F-FDG and 18F-fluoride PET scans. Bioluminescence photon flux increased exponentially on weekly follow-up. 18F-FDG PET revealed increased FDG uptake at the spine and bilaterally in the hind legs in week 2 images, and showed a progressive pattern up to 4 weeks that correlated with bioluminescence imaging. 18F-fluoride PET showed minimal abnormal findings in week 2 images, but it showed an irregular pattern at the spine from week 3 or 4 images. On quantitative analysis with standardized uptake values, a pattern of gradual increase was observed from week 2 to week 4 in both 18F-FDG PET and fluoride PET. Histopathological examination confirmed the formation of osteolytic metastasis and necrosis of the distal femur, which appeared as a photon defect on PET scans. Conclusion: Developing bone metastasis from breast cancer in a nude rat model was successfully evaluated with an animal PET imaging system and bioluminescence imaging. This nude rat model of bone metastasis, which can be evaluated by PET imaging, may be a valuable tool for evaluating early responses to novel therapeutics

  13. Bioluminescence imaging of cord blood derived mesenchymal stem cell transplanatation into myocardium

    The conventional method of analyzing myocardial cell transplanation relies on postmortem histology. We sought to demonstrate the feasibility of longitudinal monitoring transplanted cell survival in living animals using optical imaging techniques. Umblical cord blood was collected upon delivery with informed consent. Umblical mononuclear cells were obtained by negative immuno-depletion of CD3, CD14, CD19, CD38, CD66b, and glycophorin- A positive cells, followed by Ficoll- Paque density gradient centrifugation, and plated in non-coated tissue culture flasks in expansion medium. Cells were allowed to adhere overnight, thereafter non-adherent cells were washed out with medium changes. After getting the MSCs, they were transfected [multiplicity of infection (MOl) = 40) with Ad-CMV-Fluc overnight. Rats (n=4) underwent intramyocardial injection of 5 x 105 MSCs expressing firefly luciferase (Fluc) reporter gene. Optical bioluminescence imaging was performed using the charged-coupled device camera (Xenogen) from the 1st day of transplantion. Cardiac bioluminescence signals were present from 2nd day of transplantation. Cardiac signals were clearly present at day 2 (9.2x103p/s/cm2/sr). The signal reduced from day 3. The locations, magnitude, and survival duration of cord blood derived MSCs were monitored noninvasively. With further development, molecular imaging studies should add critical insights into cardiac cell transplantation

  14. Relation between deep bioluminescence and oceanographic variables: A statistical analysis using time-frequency decompositions

    Martini, S.; Nerini, D.; Tamburini, C.

    2014-09-01

    We consider the statistical analysis of a 1.7-year high-frequency sampled time series, between 2009 and 2010, recorded at the ANTARES observatory in the deep NW Mediterranean Sea (2475 m depth). The objective was to estimate relationships between bioluminescence and environmental time series (temperature, salinity and current speed). As this entire dataset is characterized by non-linearity and non-stationarity, two time-frequency decomposition methods (wavelet and Hilbert-Huang) were used. These mathematical methods are dedicated to the analysis of a signal at various time and frequencies scales. This work propose some statistical tools dedicated to the study of relationships between two time series. Our study highlights three events of high bioluminescence activity in March 2009, December 2009 and March 2010. We demonstrate that the two events occurring in March 2009 and 2010 are correlated to the arrival of newly formed deep water masses at frequencies of approximately 4.8×10-7 (period of 24.1 days). In contrast, the event in December 2009 is only correlated with current speed at frequencies of approximately 1.9×10-6 (period of 6.0 days). The use of both wavelet and Hilbert-Huang transformations has proven to be successful for the analysis of multivariate time series. These methods are well-suited in a context of the increasing number of long time series recorded in oceanography.

  15. Bioluminescence Imaging of NADPH Oxidase Activity in Different Animal Models

    Han, Wei; Li, Hui; Segal, Brahm H.; Blackwell, Timothy S.

    2012-01-01

    NADPH oxidase is a critical enzyme that mediates antibacterial and antifungal host defense. In addition to its role in antimicrobial host defense, NADPH oxidase has critical signaling functions that modulate the inflammatory response 1. Thus, the development of a method to measure in "real-time" the kinetics of NADPH oxidase-derived ROS generation is expected to be a valuable research tool to understand mechanisms relevant to host defense, inflammation, and injury.

  16. Self-calibrated algorithms for diffuse optical tomography and bioluminescence tomography using relative transmission images.

    Naser, Mohamed A; Patterson, Michael S; Wong, John W

    2012-11-01

    Reconstruction algorithms for diffuse optical tomography (DOT) and bioluminescence tomography (BLT) have been developed based on diffusion theory. The algorithms numerically solve the diffusion equation using the finite element method. The direct measurements of the uncalibrated light fluence rates by a camera are used for the reconstructions. The DOT is self-calibrated by using all possible pairs of transmission images obtained with external sources along with the relative values of the simulated data and the calculated Jacobian. The reconstruction is done in the relative domain with the cancelation of any geometrical or optical factors. The transmission measurements for the DOT are used for calibrating the bioluminescence measurements at each wavelength and then a normalized system of equations is built up which is self-calibrated for the BLT. The algorithms have been applied to a three dimensional model of the mouse (MOBY) segmented into tissue regions which are assumed to have uniform optical properties. The DOT uses the direct method for calculating the Jacobian. The BLT uses a reduced space of eigenvectors of the Green's function with iterative shrinking of the permissible source region. The reconstruction results of the DOT and BLT algorithms show good agreement with the actual values when using either absolute or relative data. Even a small calibration error causes significant degradation of the reconstructions based on absolute data. PMID:23162719

  17. Quantitative Imaging of D-2-Hydroxyglutarate in Selected Histological Tissue Areas by a Novel Bioluminescence Technique

    Voelxen, Nadine F.; Walenta, Stefan; Proescholdt, Martin; Dettmer, Katja; Pusch, Stefan; Mueller-Klieser, Wolfgang

    2016-01-01

    Patients with malignant gliomas have a poor prognosis with average survival of less than 1 year. Whereas in other tumor entities the characteristics of tumor metabolism are successfully used for therapeutic approaches, such developments are very rare in brain tumors, notably in gliomas. One metabolic feature characteristic of gliomas, in particular diffuse astrocytomas and oligodendroglial tumors, is the variable content of D-2-hydroxyglutarate (D2HG), a metabolite that was discovered first in this tumor entity. D2HG is generated in large amounts due to various “gain-of-function” mutations in the isocitrate dehydrogenases IDH1 and IDH2. Meanwhile, D2HG has been detected in several other tumor entities, including intrahepatic bile-duct cancer, chondrosarcoma, acute myeloid leukemia, and angioimmunoblastic T-cell lymphoma. D2HG is barely detectable in healthy tissue (bioluminescence assay for determining D2HG in sections of snap-frozen tissue. The assay was verified independently by photometric tests and liquid chromatography/mass spectrometry. The novel technique allows the microscopically resolved determination of D2HG in a concentration range of 0–10 μmol/g tissue (wet weight). In combination with the already established bioluminescence imaging techniques for ATP, glucose, pyruvate, and lactate, the novel D2HG assay enables a comparative characterization of the metabolic profile of individual tumors in a further dimension. PMID:27014623

  18. Use of a highly sensitive two-dimensional luminescence imaging system to monitor endogenous bioluminescence in plant leaves

    Flor-Henry Michel; McCabe Tulene C; de Bruxelles Guy L; Roberts Michael R

    2004-01-01

    Abstract Background All living organisms emit spontaneous low-level bioluminescence, which can be increased in response to stress. Methods for imaging this ultra-weak luminescence have previously been limited by the sensitivity of the detection systems used. Results We developed a novel configuration of a cooled charge-coupled device (CCD) for 2-dimensional imaging of light emission from biological material. In this study, we imaged photon emission from plant leaves. The equipment allowed sho...

  19. A fast full-body fluorescence/bioluminescence imaging system for small animals

    Lee, Jong Hwan; Kim, Hyun Keol; Jia, Jingfei; Fong, Christopher; Hielscher, Andreas H.

    2013-03-01

    Whole body in vivo optical imaging of small animals has widened its applications and increased the capabilities for preclinical researches. However, most commercial and prototype optical imaging systems are camera-based systems using epi- or trans- illumination mode, with limited views of small animals. And for more accurate tomographic image reconstruction, additional data and information of a target animal is necessary. To overcome these issues, researchers have suggested several approaches such as maximizing the detection area or using the information of other highresolution modalities such as CT, MRI or Ultrasound, or using multi-spectral signals. As one of ways to maximizing the detection area of a target animal, we present a new fluorescence and bioluminescence imaging system for small animals, which can image entire surface of a target animal simultaneously. This system uses double mirror reflection scheme and it consists of input unit, imaging unit with two conical mirrors, the source illumination part and the surface scanner, and the detection unit with an intensified CCD camera system. Two conical mirrors are configured that a larger size mirror captures a target animal surface, and a smaller size mirror projects this captured image onto a CCD camera with one acquisition. With this scheme, we could capture entire surface of a target animal simultaneously and improve back reflection issue between a mirror and an animal surface of a single conical mirror scheme. Additionally, we could increase accessibility to an animal for multi-modality integration by providing unobstructed space around a target animal.

  20. Assessing the effect of EPO on tumor oxygenation and radioresponsiveness via in vivo bioluminescence imaging

    Evaluating tumor kill by volume measurement lacks sensitivity while in vivo-in vitro and histological assays are unsuitable for serial measurements. In vivo bioluminescence imaging (BI) nondestructively measures the number of metabolically active cells containing luciferase (LUC) over time. In this paper, the effect of erythropoietin (EPO) on tumor oxygenation and radioresponsivenessis is studied using BI and conventional methods. Murine adenocarcinoma cells, transfected with the LUC gene, were placed in the flank of BALB/C mice. EPO 1 u/g or saline was injected sc tiw for two weeks, starting the day of transplant. Mice then underwent irradiation (XRT) or pO2 measurement with an optical probe. In BI, mice were injected with luciferin and total photon flux (TPF) measured with a CCD camera. In vitro, cells were plated, irradiated and incubated at 37 deg C. Initial hematocrit was 47% (n=119) vs. 61% in EPO-treated mice (n=23, p2 (6.4 vs. 4.7 mm Hg, p=0.04) than controls. For 1-3x7 Gy, TPF was stable for 2 days after the start of XRT, then fell precipitously. Two weeks post XRT, TPF was 10-5 the initial value and a nidus of LUC activity persisted for months in most tumors. Tumor volume decreased only 1-2 orders of magnitude. For 3x7 Gy, tumor regrew in 1/11 EPO-TM and controls (p=NS.) For 1x7 Gy, tumors regrew in 4/6 EPO-TM and 2/4 controls (p=NS). TPF did not increase with tumor regrowth. Recurrent tumors exhibited lower median pO2 (2.1 mm Hg, p=.003) and higher hypoxic fraction than controls. A clonogenic assay yielded D10 = 3.7 Gy with all colonies expressing LUC. The TPF of 0-Gy treated wells rose significantly over incubation, while that of wells treated to 10 Gy was unchanged. Though EPO improved tumor oxygenation, no effect on XRT-mediated cell kill was seen. BI measured tumor killing in vivo over a broad dynamic range. The results suggest that cell killing in vivo is a multistep process, amplified by humoral factors

  1. Tomographic bioluminescence imaging by use of a combined optical-PET (OPET) system: a computer simulation feasibility study

    Alexandrakis, George; Rannou, Fernando R.; Chatziioannou, Arion F.

    2005-01-01

    The feasibility and limits in performing tomographic bioluminescence imaging with a combined optical-PET (OPET) system was explored by simulating its image formation process. A micro-MRI based virtual mouse phantom was assigned appropriate tissue optical properties to each of its segmented internal organs at wavelengths spanning the emission spectrum of the firefly luciferase at 37 °C. The TOAST finite-element code was employed to simulate the diffuse transport of photons emitted from biolumi...

  2. Engraftment and bone mass are enhanced by PTHrP 1-34 in ectopically transplanted vertebrae (vossicle model) and can be non-invasively monitored with bioluminescence and fluorescence imaging.

    Hildreth, Blake Eason; Williams, Michelle M; Dembek, Katarzyna A; Hernon, Krista M; Rosol, Thomas J; Toribio, Ramiro E

    2015-12-01

    Evidence exists that parathyroid hormone-related protein (PTHrP) 1-34 may be more anabolic in bone than parathyroid hormone 1-34. While optical imaging is growing in popularity, scant information exists on the relationships between traditional bone imaging and histology and bioluminescence (BLI) and fluorescence (FLI) imaging. We aimed to evaluate the effects of PTHrP 1-34 on bone mass and determine if relationships existed between radiographic and histologic findings in bone and BLI and FLI indices. Vertebrae (vossicles) from mice coexpressing luciferase and green fluorescent protein were implanted subcutaneously into allogenic nude mice. Transplant recipients were treated daily with saline or PTHrP 1-34 for 4weeks. BLI, FLI, radiography, histology, and CT of the vossicles were performed over time. PTHrP 1-34 increased bioluminescence the most after 2weeks, fluorescence at all time points, and decreased the time to peak bioluminescence at 4weeks (P?0.027), the latter of which suggesting enhanced engraftment. PTHrP 1-34 maximized vertebral body volume at 4weeks (Pbioluminescence (r=0.595; P=0.019); (2) total fluorescence (r=0.474; P=0.074); and (3) max fluorescence (r=0.587; P=0.021). In conclusion, PTHrP 1-34 enhances engraftment and bone mass, which can be monitored non-invasively by BLI and FLI. PMID:26271486

  3. Influence of antibiotic pressure on bacterial bioluminescence, with emphasis on Staphylococcus aureus.

    Daghighi, Seyedmojtaba; Sjollema, Jelmer; Harapanahalli, Akshay; Dijkstra, Rene J B; van der Mei, Henny C; Busscher, Henk J

    2015-12-01

    Bioluminescence imaging is used for longitudinal evaluation of bacteria in live animals. Clear relations exist between bacterial numbers and their bioluminescence. However, bioluminescence images of Staphylococcus aureus Xen29, S. aureus Xen36 and Escherichia coli Xen14 grown on tryptone soy agar in Etests demonstrated increased bioluminescence at sub-MICs of different antibiotics. This study aimed to further evaluate the influence of antibiotic pressure on bioluminescence in S. aureus Xen29. Bioluminescence of S. aureus Xen29, grown planktonically in tryptone soy broth, was quantified in the absence and presence of different concentrations of vancomycin, ciprofloxacin, erythromycin or chloramphenicol and was related to expression of the luxA gene under antibiotic pressure measured using real-time PCR. In the absence of antibiotics, staphylococcal bioluminescence increased over time until a maximum after ca. 6h of growth, and subsequently decreased to the detection threshold after 24h of growth owing to reduced bacterial metabolic activity. Up to MICs of the antibiotics, bioluminescence increased according to a similar pattern up to 6h of growth, but after 24h bioluminescence was higher than in the absence of antibiotics. Contrary to expectations, bioluminescence per organism (CFU) after different growth periods in the absence and at MICs of different antibiotics decreased with increasing expression of luxA. Summarising, antibiotic pressure impacts the relation between CFU and bioluminescence. Under antibiotic pressure, bioluminescence is not controlled by luxA expression but by co-factors impacting the bacterial metabolic activity. This conclusion is of utmost importance when evaluating antibiotic efficacy in live animals using bioluminescent bacterial strains. PMID:26526893

  4. Fast iterative image reconstruction methods for fully 3D multispectral bioluminescence tomography

    We investigate fast iterative image reconstruction methods for fully 3D multispectral bioluminescence tomography for applications in small animal imaging. Our forward model uses a diffusion approximation for optically inhomogeneous tissue, which we solve using a finite element method (FEM). We examine two approaches to incorporating the forward model into the solution of the inverse problem. In a conventional direct calculation approach one computes the full forward model by repeated solution of the FEM problem, once for each potential source location. We describe an alternative on-the-fly approach where one does not explicitly solve for the full forward model. Instead, the solution to the forward problem is included implicitly in the formulation of the inverse problem, and the FEM problem is solved at each iteration for the current image estimate. We evaluate the convergence speeds of several representative iterative algorithms. We compare the computation cost of those two approaches, concluding that the on-the-fly approach can lead to substantial reductions in total cost when combined with a rapidly converging iterative algorithm

  5. Metabolic imaging in microregions of tumors and normal tissues with bioluminescence and photon counting

    A method has been developed for metabolic imaging on a microscopic level in tumors, tumor spheroids, and normal tissues. The technique makes it possible to determine the spatial distribution of glucose, lactate, and ATP in absolute terms at similar locations within tissues or cell aggregates. The substrate distributions are registered in serial cryostat sections from tissue cryobiopsies or from frozen spheroids with the use of bioluminescence reactions. The light emission is measured directly by a special imaging photon counting system enabling on-line image analysis. The technique has been applied to human breast cancer xenografts, to spheroids originating from a human colon adenocarcinoma, and to skeletal rat muscle. Preliminary data obtained indicate that heterogeneities in the substrate distributions measured are much more pronounced in tumors than in normal tissue. There was no obvious correlation among the three quantities measured at similar locations within the tissues. The distribution of ATP corresponded well with the histological structure of larger spheroids; values were low in the necrotic center and high in the viable rim of these cell aggregates

  6. Potential of Induced Metabolic Bioluminescence Imaging to Uncover Metabolic Effects of Antiangiogenic Therapy in Tumors.

    Indraccolo, Stefano; Mueller-Klieser, Wolfgang

    2016-01-01

    Tumor heterogeneity at the genetic level has been illustrated by a multitude of studies on the genomics of cancer, but whether tumors can be heterogeneous at the metabolic level is an issue that has been less systematically investigated so far. A burning-related question is whether the metabolic features of tumors can change either following natural tumor progression (i.e., in primary tumors versus metastasis) or therapeutic interventions. In this regard, recent findings by independent teams indicate that antiangiogenic drugs cause metabolic perturbations in tumors as well as metabolic adaptations associated with increased malignancy. Induced metabolic bioluminescence imaging (imBI) is an imaging technique that enables detection of key metabolites associated with glycolysis, including lactate, glucose, pyruvate, and ATP in tumor sections. Signals captured by imBI can be used to visualize the topographic distribution of these metabolites and quantify their absolute amount. imBI can be very useful for metabolic classification of tumors as well as to track metabolic changes in the glycolytic pathway associated with certain therapies. Imaging of the metabolic changes induced by antiangiogenic drugs in tumors by imBI or other emerging technologies is a valuable tool to uncover molecular sensors engaged by metabolic stress and offers an opportunity to understand how metabolism-based approaches could improve cancer therapy. PMID:26870694

  7. Potential of Induced Metabolic Bioluminescence Imaging to Uncover Metabolic Effects of Antiangiogenic Therapy in Tumors

    Indraccolo, Stefano; Mueller-Klieser, Wolfgang

    2016-01-01

    Tumor heterogeneity at the genetic level has been illustrated by a multitude of studies on the genomics of cancer, but whether tumors can be heterogeneous at the metabolic level is an issue that has been less systematically investigated so far. A burning-related question is whether the metabolic features of tumors can change either following natural tumor progression (i.e., in primary tumors versus metastasis) or therapeutic interventions. In this regard, recent findings by independent teams indicate that antiangiogenic drugs cause metabolic perturbations in tumors as well as metabolic adaptations associated with increased malignancy. Induced metabolic bioluminescence imaging (imBI) is an imaging technique that enables detection of key metabolites associated with glycolysis, including lactate, glucose, pyruvate, and ATP in tumor sections. Signals captured by imBI can be used to visualize the topographic distribution of these metabolites and quantify their absolute amount. imBI can be very useful for metabolic classification of tumors as well as to track metabolic changes in the glycolytic pathway associated with certain therapies. Imaging of the metabolic changes induced by antiangiogenic drugs in tumors by imBI or other emerging technologies is a valuable tool to uncover molecular sensors engaged by metabolic stress and offers an opportunity to understand how metabolism-based approaches could improve cancer therapy. PMID:26870694

  8. The Influence of Hypoxia and pH on Bioluminescence Imaging of Luciferase-Transfected Tumor Cells and Xenografts

    Kristoffer Valerie; Chung, Theodore D.; Elizabeth Rosenberg; Sarah E. Golding; Dever, Seth M.; Peck Sun Lin; Broaddus, William C.; Mark J. Jameson; Khalil, Ashraf A.

    2013-01-01

    Bioluminescence imaging (BLI) is a relatively new noninvasive technology used for quantitative assessment of tumor growth and therapeutic effect in living animal models. BLI involves the generation of light by luciferase-expressing cells following administration of the substrate luciferin in the presence of oxygen and ATP. In the present study, the effects of hypoxia, hypoperfusion, and pH on BLI signal (BLS) intensity were evaluated in vitro using cultured cells and in vivo using a xenograft...

  9. Direct Evidence of Mesenchymal Stem Cell Tropism for Tumor and Wounding Microenvironments using In Vivo Bioluminescence Imaging

    Kidd, Shannon; Spaeth, Erika; Dembinski, Jennifer L.; Dietrich, Martin; Watson, Keri; Klopp, Ann; Battula, Lokesh; Weil, Micheal; Andreeff, Michael; Marini, Frank C

    2009-01-01

    Multipotent mesenchymal stromal/stem cells (MSC) have shown potential clinical utility. However, previous assessments of MSC behavior in recipients have relied on visual detection in host tissue following sacrifice, failing to monitor in vivo MSC dispersion in a single animal and limiting the number of variables that can be observed concurrently. In this study, we utilized noninvasive, in vivo bioluminescent imaging to determine conditions under which MSC selectively engraft in sites of infla...

  10. Physicochemical characterization and in vivo bioluminescence imaging of nanostructured lipid carriers for targeting the brain: apomorphine as a model drug

    Nanostructured lipid carriers (NLCs) were prepared to investigate whether the duration of brain targeting and accumulation of drugs in the brain can be improved by intravenous delivery. NLCs were developed using cetyl palmitate as the lipid matrix, squalene as the cationic surfactant, and Pluronic F68, polysorbate 80 and polyethylene glycol as the interfacial additives. Solid lipid nanoparticles (SLNs) and lipid emulsions (LEs) were also prepared for comparison. An anti-Parkinson's drug, apomorphine, was used as the model drug. Nuclear magnetic resonance and differential scanning calorimetry showed possible interactions between the solid and liquid lipids in the inner core. The lipid nanoparticles with different compositions were characterized by mean size, zeta potential, apomorphine encapsulation and in vitro drug release. NLCs were 370-430 nm in size, which was between the sizes of the SLNs and LEs. A cationic surfactant was used to produce a positive surface charge of 42-50 mV. The base form of apomorphine was successfully entrapped by NLCs with an entrapment percentage of > 60%. The loading of apomorphine in nanoparticles resulted in a slower release behavior compared to the aqueous solution, with LEs showing the lowest release. In vivo real-time bioluminescence imaging of the rat brain revealed that NLCs could be targeted, through certain vessels, to selected brain regions. This effect was further confirmed by imaging the entire brain and brain slices. The results indicated that NLCs with moderate additives are a promising controlled-release and drug-targeting system.

  11. Physicochemical characterization and in vivo bioluminescence imaging of nanostructured lipid carriers for targeting the brain: apomorphine as a model drug

    Hsu, Shu-Hui [Department of Pharmacy, Chia Nan University of Pharmacy and Science, Tainan 717, Taiwan (China); Wen, Chih-Jen; Yen, Tzu-Chen [Animal Molecular Imaging Center, Chang Gung Memorial Hospital, Kweishan, Taoyuan 333, Taiwan (China); Al-Suwayeh, S A; Fang, Jia-You [Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh (Saudi Arabia); Chang, Hui-Wen, E-mail: fajy@mail.cgu.edu.tw [Pharmaceutics Laboratory, Graduate Institute of Natural Products, Chang Gung University, Kweishan, Taoyuan 333, Taiwan (China)

    2010-10-08

    Nanostructured lipid carriers (NLCs) were prepared to investigate whether the duration of brain targeting and accumulation of drugs in the brain can be improved by intravenous delivery. NLCs were developed using cetyl palmitate as the lipid matrix, squalene as the cationic surfactant, and Pluronic F68, polysorbate 80 and polyethylene glycol as the interfacial additives. Solid lipid nanoparticles (SLNs) and lipid emulsions (LEs) were also prepared for comparison. An anti-Parkinson's drug, apomorphine, was used as the model drug. Nuclear magnetic resonance and differential scanning calorimetry showed possible interactions between the solid and liquid lipids in the inner core. The lipid nanoparticles with different compositions were characterized by mean size, zeta potential, apomorphine encapsulation and in vitro drug release. NLCs were 370-430 nm in size, which was between the sizes of the SLNs and LEs. A cationic surfactant was used to produce a positive surface charge of 42-50 mV. The base form of apomorphine was successfully entrapped by NLCs with an entrapment percentage of > 60%. The loading of apomorphine in nanoparticles resulted in a slower release behavior compared to the aqueous solution, with LEs showing the lowest release. In vivo real-time bioluminescence imaging of the rat brain revealed that NLCs could be targeted, through certain vessels, to selected brain regions. This effect was further confirmed by imaging the entire brain and brain slices. The results indicated that NLCs with moderate additives are a promising controlled-release and drug-targeting system.

  12. Effects of Photodynamic Therapy on Gram-Positive and Gram-Negative Bacterial Biofilms by Bioluminescence Imaging and Scanning Electron Microscopic Analysis

    Garcez, Aguinaldo S.; Nez, Silvia C.; Azambuja, Nilton; Fregnani, Eduardo R.; Rodriguez, Helena M.H.; Hamblin, Michael R.; Suzuki, Hideo; Ribeiro, Martha S.

    2013-01-01

    Objective: The aim of this study was to test photodynamic therapy (PDT) as an alternative approach to biofilm disruption on dental hard tissue, We evaluated the effect of methylene blue and a 660?nm diode laser on the viability and architecture of Gram-positive and Gram-negative bacterial biofilms. Materials and methods: Ten human teeth were inoculated with bioluminescent Pseudomonas aeruginosa or Enterococcus faecalis to form 3 day biofilms in prepared root canals. Bioluminescence imaging wa...

  13. Evaluation of monkeypox virus infection of prairie dogs (Cynomys ludovicianus) using in vivo bioluminescent imaging

    Falendysz, Elizabeth A.; Londoo-Navas, Angela M.; Meteyer, Carol U.; Pussini, Nicola; Lopera, Juan G.; Osorio, Jorge E.; Rocke, Tonie E.

    2014-01-01

    Monkeypox (MPX) is a re-emerging zoonotic disease that is endemic in Central and West Africa, where it can cause a smallpox-like disease in humans. Despite many epidemiologic and field investigations of MPX, no definitive reservoir species has been identified. Using recombinant viruses expressing the firefly luciferase (luc) gene, we previously demonstrated the suitability of in vivo bioluminescent imaging (BLI) to study the pathogenesis of MPX in animal models. Here, we evaluated BLI as a novel approach for tracking MPX virus infection in black-tailed prairie dogs (Cynomys ludovicianus). Prairie dogs were affected during a multistate outbreak of MPX in the US in 2003 and have since been used as an animal model of this disease. Our BLI results were compared with PCR and virus isolation from tissues collected postmortem. Virus was easily detected and quantified in skin and superficial tissues by BLI before and during clinical phases, as well as in subclinical secondary cases, but was not reliably detected in deep tissues such as the lung. Although there are limitations to viral detection in larger wild rodent species, BLI can enhance the use of prairie dogs as an animal model of MPX and can be used for the study of infection, disease progression, and transmission in potential wild rodent reservoirs.

  14. Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria

    Saleh, Malek; Abdullah, Mohammed R.; Schulz, Christian; Kohler, Thomas; Pribyl, Thomas; Jensch, Inga; Hammerschmidt, Sven

    2014-01-01

    Pneumonia is one of the major health care problems in developing and industrialized countries and is associated with considerable morbidity and mortality. Despite advances in knowledge of this illness, the availability of intensive care units (ICU), and the use of potent antimicrobial agents and effective vaccines, the mortality rates remain high1. Streptococcus pneumoniae is the leading pathogen of community-acquired pneumonia (CAP) and one of the most common causes of bacteremia in humans. This pathogen is equipped with an armamentarium of surface-exposed adhesins and virulence factors contributing to pneumonia and invasive pneumococcal disease (IPD). The assessment of the in vivo role of bacterial fitness or virulence factors is of utmost importance to unravel S. pneumoniae pathogenicity mechanisms. Murine models of pneumonia, bacteremia, and meningitis are being used to determine the impact of pneumococcal factors at different stages of the infection. Here we describe a protocol to monitor in real-time pneumococcal dissemination in mice after intranasal or intraperitoneal infections with bioluminescent bacteria. The results show the multiplication and dissemination of pneumococci in the lower respiratory tract and blood, which can be visualized and evaluated using an imaging system and the accompanying analysis software. PMID:24637643

  15. Development of bioluminescent Salmonella strains for use in food safety

    Bailey R Hartford

    2008-01-01

    Full Text Available Abstract Background Salmonella can reside in healthy animals without the manifestation of any adverse effects on the carrier. If raw products of animal origin are not handled properly during processing or cooked to a proper temperature during preparation, salmonellosis can occur. In this research, we developed bioluminescent Salmonella strains that can be used for real-time monitoring of the pathogen's growth on food products. To accomplish this, twelve Salmonella strains from the broiler production continuum were transformed with the broad host range plasmid pAKlux1, and a chicken skin attachment model was developed. Results Salmonella strains carrying pAKlux1 constitutively expressed the luxCDABE operon and were therefore detectable using bioluminescence. Strains were characterized in terms of bioluminescence properties and plasmid stability. To assess the usefulness of bioluminescent Salmonella strains in food safety studies, we developed an attachment model using chicken skin. The effect of washing on attachment of Salmonella strains to chicken skin was tested using bioluminescent strains, which revealed the attachment properties of each strain. Conclusion This study demonstrated that bioluminescence is a sensitive and effective tool to detect Salmonella on food products in real-time. Bioluminescence imaging is a promising technology that can be utilized to evaluate new food safety measures for reducing Salmonella contamination on food products.

  16. In vivo monitoring of fetoplacental Vegfr2 gene activity in a murine pregnancy model using a Vegfr2-luc reporter gene and bioluminescent imaging

    Rude Brian J

    2011-04-01

    Full Text Available Abstract Background Vascular endothelial growth factor receptor-2 (VEGFR2 plays a pivotal role in angiogenesis by eliciting vascular endothelial cell growth when bound to VEGF, a powerful pro-angiogenic ligand. While Vegf and Vegfr2 are expressed throughout gestation, the latter third of gestation in mice is characterized by a marked increase in fetoplacental angiogenesis. Thus, the objective of this study was to determine the feasibility of monitoring fetoplacental Vegfr2 gene activity non-invasively using a Vegfr2-luc reporter transgenic mouse and bioluminescent imaging. Methods Imaging parameters were optimized using two wild-type (WT females, bearing Vegfr2-luc fetuses. Then, seven WT females, bred to Vegfr2-luc males, were imaged from gestational day (GD 12 to 18 to determine the usefulness of the Vegfr2-luc mouse as a model for studying fetoplacental Vegfr2 activity during pregnancy. Semi-quantitative RT-PCR of Vegfr2 was also performed on whole fetoplacental units during this time. Additionally, resultant neonates were imaged at postnatal day (PND 7, 14 and 21 to monitor Vegfr2 activity during post-natal development. Results Fetoplacental Vegfr2 gene activity was detected as light emissions beginning on GD 12 of gestation and increased throughout the imaging period (P Conclusions In utero fetoplacental Vegfr2 gene activity was monitored longitudinally in a quantitative manner using a luciferase reporter gene and bioluminescent imaging during the latter third of gestation. This study demonstrates the feasibility of using the Vegfr2-luc mouse to monitor late gestation fetoplacental angiogenic activity under normal and experimental conditions. Additionally, neonatal Vegfr2 gene activity was monitored for three weeks postpartum, allowing continuous monitoring of Vegfr2 activity during the latter third of gestation and postnatal development within the same animals.

  17. Establishment of cell strains stably-transfected with luciferase gene mediated by retrovirus and their detection with bioluminescence imaging system

    Hai-juan WANG

    2012-05-01

    Full Text Available Objective  To establish cell strains stably transfected with Luciferase gene (Luc2, which was mediated by retrovirus, and explore the relationship between the number of Luc2-positive cells and light flux from bioluminescence imaging system by experiments in vitro and in vivo. Methods  We co-transfected pMX-Luc2 plasmid and pMD.G plasmid into 293T gag-pol cells to get retrovirus expressing Luc2 gene. Stable Luc2 positive cell lines were generated and screened by transduction of Retro-Luc2 in mouse colon cancer cell line CT26, human non-small cell lung cancer cell line NCI-H446, human colon cancer cell line HT-29, human ovarian carcinoma cell line SKOV3 and human hepatocellular carcinoma cell line SMMC-7721, all of them were identified by bioluminescence imaging system. Different numbers of SKOV3-Luc2 cells ranging from 10 to 10000 were plated onto culture dishes. Two xenograft models of ovarian cancer were reproduced by subcutaneous injection of 200μl SKOV3-Luc2 cell suspension with different concentrations (1×107, 5×106, 2.5×106, 1×106, 5×105, 2.5×105, 1×105 and 5×104/ml into 16 sites on the back of 4 nude mice, or intravenous injection of 1×106 or 3 ×106 SKOV3-Luc2 cells into the tail vein. Light flux value of SKOV3-Luc2 cells in dishes and in mice was measured by bioluminescence imaging system. Results  Retro-Luc2 was constructed successfully and expressed Luc2 stably in transduced CT26, NCI-H446, HT-29, SKOV3 and SMMC-7721 cell lines. Light flux was correlated in a linear manner with the number of Luc2-positive cells in dishes and in mice (R2=0.944, β=0.972; R2=0.991, β=0.996; R2=0.351, β=0.628; P < 0.01. Conclusion  Luc2-positive cell lines could be established rapidly and accurately by infecting tumor cells with retrovirus expressing Luc2. The number of Luc2 positive cells is significantly related in a linear manner to light flux from bioluminescence imaging system in vitro and in vivo.

  18. Bioluminescent imaging of TRAIL-induced apoptosis through detection of caspase activation following cleavage of DEVD-aminoluciferin.

    Liu, Jue Judy; Wang, Wenge; Dicker, David T; El-Deiry, Wafik S

    2005-08-01

    Apoptosis, the most common and well-defined form of programmed cell death (PCD), is often impaired in cancer and neurodegenerative diseases and can limit conventional therapy. Bioluminescent molecular imaging was employed to study apoptosis in human colon cancer cells that have been treated with various doses of the therapeutic agent TRAIL (tumor necrosis factor-related apoptosis inducing ligand). While monitoring therapeutic response through a proluminescent, caspase-activated DEVD-aminoluciferin reagent (Caspase-Glo 3/7) which produced strong, stable signals, alternate preparations of the reagent were explored for non-invasive imaging methods. Dissolving the lyophilized DEVD-aminoluciferin compound in Dulbecco's PBS instead of lysis buffer (along with heat inactivation of an accompanying exogenous luciferase protein by heating at 85 degrees C for 20 minutes) yielded a minimally invasive apoptosis detector, with maximum luminescence intensities 2.5-fold stronger than those produced by D-luciferin at a final concentration of 100 microg/mL. Bioluminescent imaging of cancer therapeutic response through minimally invasive detection of caspase activation may serve as an important tool in monitoring apoptosis in vivo and in vitro. PMID:16177559

  19. Synthetic strategies for controlling inter- and intramolecular interactions: Applications in single-molecule fluorescence imaging, bioluminescence imaging, and palladium catalysis

    Conley, Nicholas R.

    The field of synthetic organic chemistry has reached such maturity that, with sufficient effort and resources, the synthesis of virtually any small molecule which exhibits reasonable stability at room temperature can be realized. While representing a monumental achievement for the field, the ability to exert precise control over molecular structure is just a means to an end, and it is frequently the responsibility of the synthetic chemist to determine which molecules should actually be synthesized. For better or worse, there exists no competitive free market in academia for new molecules, and as a result, the decision of which compounds should be synthesized is seldom driven by the forces of supply and demand; rather, it is guided by the synthetic chemist's interest in an anticipated structure-function relationship or in the properties of a previously unstudied class of molecules. As a consequence, there exists a pervasive need for chemists with synthetic expertise in fields (e.g., molecular imaging) and subdisciplines of chemistry (e.g., physical chemistry) in which the identification of promising synthetic targets dramatically outpaces the synthetic output in that field or subdiscipline, and ample opportunities are available for synthetic chemists who choose to pursue such cross-disciplinary research. This thesis describes synthetic efforts that leverage these opportunities to realize applications in biological imaging and in palladium catalysis. In Part I, the synthesis and characterization of three novel luminophores and their imaging applications are discussed. The first is a molecular beacon that utilizes a fluorophorefluorophore pair which exhibits H-dimer quenching in the closed conformation. This probe offers several advantages over conventional fluorophore-quencher molecular beacons in the detection of oligonucleotides, both in bulk and at the single-molecule level. Secondly, a fluorescent, Cy3-Cy5 covalent heterodimer is reported, which on account of the proximity of the Cy3 and Cy5 fluorophores, behaves as an optical photoswitch in the presence of a thiol reagent. This unique property was employed to achieve sub-diffraction-limited imaging of the stalks of Caulobacter crescentus cells with 30-nm resolution using STORM (stochastic optical reconstruction microscopy). Lastly, the synthesis of the first selenium analogue of firefly luciferin is described, and this analogue is shown to be a competent substrate for firefly luciferase (fLuc). Remarkably, it exhibits red-shifted bioluminescence emission relative to the native sulfur analogue. The in vivo performance of the selenium and sulfur analogues in imaging are compared by tail-vein injection into nude mice bearing subcutaneous tumor xenografts of a human breast cancer cell line that was stably transduced to express fLuc. Part II of this thesis begins by addressing design considerations in the development of palladium catalysts that effect oxidative transformations under mild conditions (i.e., 1 atm air, room temperature) using molecular oxygen as the terminal oxidant. A newly synthesized cationic palladium complex, [(2,9-dimethylphenanthroline)Pd(OAc)]2[OTf]2, is shown to catalyze aerobic alcohol oxidation under such conditions with an unprecedented initial turnover frequency, but the presence of partially reduced oxygen species results in competitive ligand oxidation with concomitant decrease in catalyst activity. To remedy this, oxidatively resistant ligands, which are essential for the development of next-generation, high-turnover-frequency palladium catalysts that utilize oxygen as a terminal oxidant, have been prepared and effectively employed. In addition, the first general palladium-catalyzed route to the carbonylation of diols is reported. In this system, carbon monoxide (1 atm) serves the carbonyl source, (2,9-dimethylphenanthroline)Pd(OAc) 2 acts as the catalyst, and N-chlorosuccinimide and iodosobenzene are the oxidants for 1,2- and 1,3-diols, respectively. This thesis illustrates the power of synthetic organic chemistry to exert precise control over the structure of molecules, thereby enabling applications in single-molecule fluorescence imaging, bioluminescence imaging, and palladium catalysis.

  20. Effect of optical property estimation accuracy on tomographic bioluminescence imaging: simulation of a combined optical-PET (OPET) system

    Inevitable discrepancies between the mouse tissue optical properties assumed by an experimenter and the actual physiological values may affect the tomographic localization of bioluminescent sources. In a previous work, the simplifying assumption of optically homogeneous tissues led to inaccurate localization of deep sources. Improved results may be obtained if a mouse anatomical map is provided by a high-resolution imaging modality and optical properties are assigned to segmented tissues. In this work, the feasibility of this approach was explored by simulating the effect of different magnitude optical property errors on the image formation process of a combined optical-PET system. Some comparisons were made with corresponding simulations using higher spatial resolution data that are typically attainable by CCD cameras. In addition, simulation results provided insights on some of the experimental conditions that could lead to poor localization of bioluminescent sources. They also provided a rough guide on how accurately tissue optical properties need to be known in order to achieve correct localization of point sources with increasing tissue depth under low background noise conditions

  1. Bioluminescent imaging reveals novel patterns of colonization and invasion in systemic Escherichia coli K1 experimental infection in the neonatal rat.

    Witcomb, Luci A; Collins, James W; McCarthy, Alex J; Frankel, Gadi; Taylor, Peter W

    2015-12-01

    Key features of Escherichia coli K1-mediated neonatal sepsis and meningitis, such as a strong age dependency and development along the gut-mesentery-blood-brain course of infection, can be replicated in the newborn rat. We examined temporal and spatial aspects of E. coli K1 infection following initiation of gastrointestinal colonization in 2-day-old (P2) rats after oral administration of E. coli K1 strain A192PP and a virulent bioluminescent derivative, E. coli A192PP-lux2. A combination of bacterial enumeration in the major organs, two-dimensional bioluminescence imaging, and three-dimensional diffuse light imaging tomography with integrated micro-computed tomography indicated multiple sites of colonization within the alimentary canal; these included the tongue, esophagus, and stomach in addition to the small intestine and colon. After invasion of the blood compartment, the bacteria entered the central nervous system, with restricted colonization of the brain, and also invaded the major organs, in line with increases in the severity of symptoms of infection. Both keratinized and nonkeratinized surfaces of esophagi were colonized to a considerably greater extent in susceptible P2 neonates than in corresponding tissues from infection-resistant 9-day-old rat pups; the bacteria appeared to damage and penetrate the nonkeratinized esophageal epithelium of infection-susceptible P2 animals, suggesting the esophagus represents a portal of entry for E. coli K1 into the systemic circulation. Thus, multimodality imaging of experimental systemic infections in real time indicates complex dynamic patterns of colonization and dissemination that provide new insights into the E. coli K1 infection of the neonatal rat. PMID:26351276

  2. Destabilized bioluminescent proteins

    Allen, Michael S.; Rakesh, Gupta; Gary, Sayler S.

    2007-07-31

    Purified nucleic acids, vectors and cells containing a gene cassette encoding at least one modified bioluminescent protein, wherein the modification includes the addition of a peptide sequence. The duration of bioluminescence emitted by the modified bioluminescent protein is shorter than the duration of bioluminescence emitted by an unmodified form of the bioluminescent protein.

  3. Ginger and Zingerone Ameliorate Lipopolysaccharide-Induced Acute Systemic Inflammation in Mice, Assessed by Nuclear Factor-?B Bioluminescent Imaging.

    Hsiang, Chien-Yun; Cheng, Hui-Man; Lo, Hsin-Yi; Li, Chia-Cheng; Chou, Pei-Chi; Lee, Yu-Chen; Ho, Tin-Yun

    2015-07-01

    Ginger is a commonly used spice in cooking. In this study, we comprehensively evaluated the anti-inflammatory activities of ginger and its component zingerone in lipopolysaccharide (LPS)-induced acute systemic inflammation in mice via nuclear factor-?B (NF-?B) bioluminescent imaging. Ginger and zingerone significantly suppressed LPS-induced NF-?B activities in cells in a dose-dependent manner, and the maximal inhibition (84.5% 3.5% and 96.2% 0.6%) was observed at 100 ?g/mL ginger and zingerone, respectively. Moreover, dietary ginger and zingerone significantly reduced LPS-induced proinflammatory cytokine production in sera by 62.9% 18.2% and 81.3% 6.2%, respectively, and NF-?B bioluminescent signals in whole body by 26.9% 14.3% and 38.5% 6.2%, respectively. In addition, ginger and zingerone suppressed LPS-induced NF-?B-driven luminescent intensities in most organs, and the maximal inhibition by ginger and zingerone was observed in small intestine. Immunohistochemical staining further showed that ginger and zingerone decreased interleukin-1? (IL-1?)-, CD11b-, and p65-positive areas in jejunum. In conclusion, our findings suggested that ginger and zingerone were likely to be broad-spectrum anti-inflammatory agents in most organs that suppressed the activation of NF-?B, the production of IL-1?, and the infiltration of inflammatory cells in mice. PMID:26073629

  4. A Bone Metastasis Nude Mouse Model Created by Ultrasound Guided Intracardiac Injection of Breast Cancer Cells: the Micro-CT, MRI and Bioluminescence Imaging Analysis

    Park, Young Jin; Song, Eun Hye; Kim, Seol Hwa; Song, Ho Taek; Suh, Jin Suck [Yonsei University College of Medicine, Seoul (Korea, Republic of); Choi, Sang Hyun [Korean Minjok Leadership Academy, Heongsung (Korea, Republic of)

    2011-01-15

    The purpose of this study was to develop a nude mouse model of bone metastasis by performing intracardiac injection of breast cancer cells under ultrasonography guidance and we wanted to evaluate the development and the distribution of metastasis in vivo using micro-CT, MRI and bioluminescence imaging. Animal experiments were performed in 6-week-old female nude mice. The animals underwent left ventricular injection of 2x105 MDA-MB-231Bo-Luc cells. After injection of the tumor cells, serial bioluminescence imaging was performed for 7 weeks. The findings of micro-CT, MRI and the histology were correlated with the 'hot' lesions seen on the bioluminescence imaging. Metastasis was found in 62.3% of the animals. Two weeks after intracardiac injection, metastasis to the brain, spine and femur was detected with bioluminescence imaging with an increasing intensity by week 7. Micro-CT scan confirmed multiple osteolytic lesions at the femur, spine and skull. MRI and the histology were able to show metastasis in the brain and extraskeletal metastasis around the femur. The intracardiac injection of cancer cells under ultrasonography guidance is a safe and highly reproducible method to produce bone metastasis in nude mice. This bone metastasis nude mouse model will be useful to study the mechanism of bone metastasis and to validate new therapeutics

  5. A Bone Metastasis Nude Mouse Model Created by Ultrasound Guided Intracardiac Injection of Breast Cancer Cells: the Micro-CT, MRI and Bioluminescence Imaging Analysis

    The purpose of this study was to develop a nude mouse model of bone metastasis by performing intracardiac injection of breast cancer cells under ultrasonography guidance and we wanted to evaluate the development and the distribution of metastasis in vivo using micro-CT, MRI and bioluminescence imaging. Animal experiments were performed in 6-week-old female nude mice. The animals underwent left ventricular injection of 2x105 MDA-MB-231Bo-Luc cells. After injection of the tumor cells, serial bioluminescence imaging was performed for 7 weeks. The findings of micro-CT, MRI and the histology were correlated with the 'hot' lesions seen on the bioluminescence imaging. Metastasis was found in 62.3% of the animals. Two weeks after intracardiac injection, metastasis to the brain, spine and femur was detected with bioluminescence imaging with an increasing intensity by week 7. Micro-CT scan confirmed multiple osteolytic lesions at the femur, spine and skull. MRI and the histology were able to show metastasis in the brain and extraskeletal metastasis around the femur. The intracardiac injection of cancer cells under ultrasonography guidance is a safe and highly reproducible method to produce bone metastasis in nude mice. This bone metastasis nude mouse model will be useful to study the mechanism of bone metastasis and to validate new therapeutics

  6. In vivo bioluminescence imaging of hyperglycemia exacerbating stem cells on choroidal neovascularization in mice

    Gao, Xiang; Wang, Yu; Hou, Hui-Yuan; Lyu, Yang; Wang, Hai-Yan; Yao, Li-Bo; Zhang, Jian; Cao, Feng; Wang, Yu-Sheng

    2016-01-01

    AIM To investigate the influence of hyperglycemia on the severity of choroidal neovascularization (CNV), especially the involvement of bone marrow-derived cells (BMCs) and underlying mechanisms. METHODS BMCs from firefly luciferase (Fluc)/green fluorescent protein (GFP) double transgenic mice were transplanted into C57BL/6J wide-type mice. The recipient mice were injected intraperitoneally with streptozotocin (STZ) daily for 5 consecutive days to induce diabetes mellitus (DM), followed by CNV laser photocoagulation. The BMCs recruitment in CNV exposed to hyperglycemia was firstly examined in Fluc/GFP chimeric mice by in vivo optical bioluminescence imaging (BLI) and in vitro Fluc assays. The CNV severity was evaluated by H&E staining and choroidal flatmount. The expression of vascular endothelial growth factor (VEGF) and stromal cell derived factor-1 (SDF-1) was detected by Western Blot. RESULTS BLI showed that the BMCs exerted dynamic effects in CNV model in Fluc/GFP chimeric mice exposed to hyperglycemia. The signal intensity of transplanted Fluc+GFP+ BMCs in the DM chimeric mice was significantly higher than that in the control chimeric mice with CNV induction at days 5, 7, 14 and 21 (121861.67±9948.81 vs 144998.33±13787.13 photons/second/cm2/sr for control and DM mice, P5d<0.05; 178791.67±30350.8 vs 240166.67±22605.3, P7d<0.05; 124176.67±16253.52 vs 196376.67±18556.79, P14d<0.05; 97951.60±10343.09 vs 119510.00±14383.76, P21d<0.05), which was consistent with in vitro Fluc assay at day 7 [relative light units of Fluc (RLU1)], 215.00±52.05 vs 707.33±88.65, P<0.05; RLU1/ relative light units of renilla luciferase (RLU2), 0.90±0.17 vs 1.83±0.17, P<0.05]. The CNVs in the DM mice were wider than those in the control group at days 5, 7, 14 and 21 (147.83±17.36 vs 220.33±20.17 µm, P5d<0.05; 212.17±24.63 vs 326.83±19.49, P7d<0.05; 163.17±18.24 vs 265.17±20.55, P14d<0.05; 132.00±10.88 vs 205.33±12.98, P21d<0.05). The average area of CNV in the DM group was larger at 7d (20688.67±3644.96 vs 32218.00±4132.69 µm2, P<0.05). The expression of VEGF and SDF-1 was enhanced in the DM mice. CONCLUSION Hyperglycemia promots the vasculogenesis of CNV, especially the contribution of BMCs, which might be triggered by VEGF and SDF-1 production. PMID:27162722

  7. Chemiluminescence and bioluminescence microbe detection

    Taylor, R. E.; Chappelle, E.; Picciolo, G. L.; Jeffers, E. L.; Thomas, R. R.

    1978-01-01

    Automated biosensors for online use with NASA Water Monitoring System employs bioluminescence and chemiluminescence techniques to rapidly measure microbe contamination of water samples. System eliminates standard laboratory procedures requiring time duration of 24 hours or longer.

  8. The Influence of Hypoxia and pH on Bioluminescence Imaging of Luciferase-Transfected Tumor Cells and Xenografts

    Khalil, Ashraf A.; Jameson, Mark J.; Broaddus, William C.; Lin, Peck Sun; Dever, Seth M.; Golding, Sarah E.; Rosenberg, Elizabeth; Valerie, Kristoffer; Chung, Theodore D.

    2013-01-01

    Bioluminescence imaging (BLI) is a relatively new noninvasive technology used for quantitative assessment of tumor growth and therapeutic effect in living animal models. BLI involves the generation of light by luciferase-expressing cells following administration of the substrate luciferin in the presence of oxygen and ATP. In the present study, the effects of hypoxia, hypoperfusion, and pH on BLI signal (BLS) intensity were evaluated in vitro using cultured cells and in vivo using a xenograft model in nude mice. The intensity of the BLS was significantly reduced in the presence of acute and chronic hypoxia. Changes in cell density, viability, and pH also affected BLS. Although BLI is a convenient non-invasive tool for tumor assessment, these factors should be considered when interpreting BLS intensity, especially in solid tumors that could be hypoxic due to rapid growth, inadequate blood supply, and/or treatment. PMID:23936647

  9. A novel triple-modality reporter gene for whole-body fluorescent, bioluminescent, and nuclear noninvasive imaging

    Two genetic reporter systems were developed for multimodality reporter gene imaging of different molecular-genetic processes using fluorescence, bioluminescence (BLI), and nuclear imaging techniques. The eGFP cDNA was fused at the N-terminus with HSV1-tk cDNA bearing a nuclear export signal from MAPKK (NES-HSV1-tk) or with truncation at the N-terminus of the first 45 amino acids (Δ45HSV1-tk) and with firefly luciferase at the C-terminus. A single fusion protein with three functional subunits is formed following transcription and translation from a single open reading frame. The NES-TGL (NES-TGL) or Δ45HSV1-tk/GFP/luciferase (Δ45-TGL) triple-fusion gene cDNAs were cloned into a MoMLV-based retrovirus, which was used for transduction of U87 human glioma cells. The integrity, fluorescence, bioluminescence, and enzymatic activity of the TGL reporter proteins were assessed in vitro. The predicted molecular weight of the fusion proteins (130 kDa) was confirmed by western blot. The U87-NES-TGL and U87-Δ45-TGL cells had cytoplasmic green fluorescence. The in vitro BLI was 7- and 13-fold higher in U87-NES-TGL and U87-Δ45-TGL cells compared to nontransduced control cells. The Ki of 14C-FIAU was 0.49±0.02, 0.51±0.03, and 0.003±0.001 ml/min/g in U87-NES-TGL, U87-Δ45-TGL, and wild-type U87 cells, respectively. Multimodality in vivo imaging studies were performed in nu/nu mice bearing multiple s.c. xenografts established from U87-NES-TGL, U87-Δ45-TGL, and wild-type U87 cells. BLI was performed after administration of d-luciferin (150 mg/kg i.v.). Gamma camera or PET imaging was conducted at 2 h after i.v. administration of [131I]FIAU (7.4 MBq/animal) or [124I]FIAU (7.4 MBq/animal), respectively. Whole-body fluorescence imaging was performed in parallel with the BLI and radiotracer imaging studies. In vivo BLI and gamma camera imaging showed specific localization of luminescence and radioactivity to the TGL transduced xenografts with background levels of activity in the wild-type xenografts. Tissue sampling yielded values of 0.47%±0.08%, 0.86%±0.06%, and 0.03%±0.01%dose/g [131I]FIAU in U87-NES-TGL, U87-Δ45-TGL, and U87 xenografts, respectively. The TGL triple-fusion reporter gene preserves the functional activity of its subunits and is very effective for multimodality imaging. It provides for the seamless transition from fluorescence microscopy and FACS to whole-body bioluminescence imaging, to nuclear (PET, SPET, gamma camera) imaging, and back to in situ fluorescence image analysis. (orig.)

  10. A novel triple-modality reporter gene for whole-body fluorescent, bioluminescent, and nuclear noninvasive imaging

    Ponomarev, Vladimir; Vider, Jelena; Shavrin, Aleksander; Ageyeva, Ludmila; Tourkova, Vilia [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, NY 10021, New York (United States); Doubrovin, Michael; Serganova, Inna; Beresten, Tatiana; Ivanova, Anna; Blasberg, Ronald [Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York (United States); Balatoni, Julius [Radiochemistry/Cyclotron Core Facility, Memorial Sloan-Kettering Cancer Center, New York (United States); Bornmann, William [Organic Chemistry Synthesis Core Facility, Memorial Sloan-Kettering Cancer Center, New York (United States); Gelovani Tjuvajev, Juri [Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, NY 10021, New York (United States); MD Anderson Cancer Center, 1515 Holcombe Road, Box 0057, TX 77030, Houston (United States)

    2004-05-01

    Two genetic reporter systems were developed for multimodality reporter gene imaging of different molecular-genetic processes using fluorescence, bioluminescence (BLI), and nuclear imaging techniques. The eGFP cDNA was fused at the N-terminus with HSV1-tk cDNA bearing a nuclear export signal from MAPKK (NES-HSV1-tk) or with truncation at the N-terminus of the first 45 amino acids ({delta}45HSV1-tk) and with firefly luciferase at the C-terminus. A single fusion protein with three functional subunits is formed following transcription and translation from a single open reading frame. The NES-TGL (NES-TGL) or {delta}45HSV1-tk/GFP/luciferase ({delta}45-TGL) triple-fusion gene cDNAs were cloned into a MoMLV-based retrovirus, which was used for transduction of U87 human glioma cells. The integrity, fluorescence, bioluminescence, and enzymatic activity of the TGL reporter proteins were assessed in vitro. The predicted molecular weight of the fusion proteins (130 kDa) was confirmed by western blot. The U87-NES-TGL and U87-{delta}45-TGL cells had cytoplasmic green fluorescence. The in vitro BLI was 7- and 13-fold higher in U87-NES-TGL and U87-{delta}45-TGL cells compared to nontransduced control cells. The Ki of {sup 14}C-FIAU was 0.49{+-}0.02, 0.51{+-}0.03, and 0.003{+-}0.001 ml/min/g in U87-NES-TGL, U87-{delta}45-TGL, and wild-type U87 cells, respectively. Multimodality in vivo imaging studies were performed in nu/nu mice bearing multiple s.c. xenografts established from U87-NES-TGL, U87-{delta}45-TGL, and wild-type U87 cells. BLI was performed after administration of d-luciferin (150 mg/kg i.v.). Gamma camera or PET imaging was conducted at 2 h after i.v. administration of [{sup 131}I]FIAU (7.4 MBq/animal) or [{sup 124}I]FIAU (7.4 MBq/animal), respectively. Whole-body fluorescence imaging was performed in parallel with the BLI and radiotracer imaging studies. In vivo BLI and gamma camera imaging showed specific localization of luminescence and radioactivity to the TGL transduced xenografts with background levels of activity in the wild-type xenografts. Tissue sampling yielded values of 0.47%{+-}0.08%, 0.86%{+-}0.06%, and 0.03%{+-}0.01%dose/g [{sup 131}I]FIAU in U87-NES-TGL, U87-{delta}45-TGL, and U87 xenografts, respectively. The TGL triple-fusion reporter gene preserves the functional activity of its subunits and is very effective for multimodality imaging. It provides for the seamless transition from fluorescence microscopy and FACS to whole-body bioluminescence imaging, to nuclear (PET, SPET, gamma camera) imaging, and back to in situ fluorescence image analysis. (orig.)

  11. Candida albicans biofilm development on medically-relevant foreign bodies in a mouse subcutaneous model followed by bioluminescence imaging.

    Kucharkov, So?a; Vande Velde, Greetje; Himmelreich, Uwe; Van Dijck, Patrick

    2015-01-01

    Candida albicans biofilm development on biotic and/or abiotic surfaces represents a specific threat for hospitalized patients. So far, C. albicans biofilms have been studied predominantly in vitro but there is a crucial need for better understanding of this dynamic process under in vivo conditions. We developed an in vivo subcutaneous rat model to study C. albicans biofilm formation. In our model, multiple (up to 9) Candida-infected devices are implanted to the back part of the animal. This gives us a major advantage over the central venous catheter model system as it allows us to study several independent biofilms in one animal. Recently, we adapted this model to study C. albicans biofilm development in BALB/c mice. In this model, mature C. albicans biofilms develop within 48 hr and demonstrate the typical three-dimensional biofilm architecture. The quantification of fungal biofilm is traditionally analyzed post mortem and requires host sacrifice. Because this requires the use of many animals to perform kinetic studies, we applied non-invasive bioluminescence imaging (BLI) to longitudinally follow up in vivo mature C. albicans biofilms developing in our subcutaneous model. C. albicans cells were engineered to express the Gaussia princeps luciferase gene (gLuc) attached to the cell wall. The bioluminescence signal is produced by the luciferase that converts the added substrate coelenterazine into light that can be measured. The BLI signal resembled cell counts obtained from explanted catheters. Non-invasive imaging for quantifying in vivo biofilm formation provides immediate applications for the screening and validation of antifungal drugs under in vivo conditions, as well as for studies based on host-pathogen interactions, hereby contributing to a better understanding of the pathogenesis of catheter-associated infections. PMID:25651138

  12. Live Imaging of Bioluminescent Leptospira interrogans in Mice Reveals Renal Colonization as a Stealth Escape from the Blood Defenses and Antibiotics

    Ratet, Gwenn; Veyrier, Frdric J.; Fanton d'Andon, Martine; Kammerscheit, Xavier; Nicola, Marie-Anne; Picardeau, Mathieu; Boneca, Ivo G.; Werts, Catherine

    2014-01-01

    Leptospira (L.) interrogans are bacteria responsible for a worldwide reemerging zoonosis. Some animals asymptomatically carry L. interrogans in their kidneys and excrete bacteria in their urine, which contaminates the environment. Humans are infected through skin contact with leptospires and develop mild to severe leptospirosis. Previous attempts to construct fluorescent or bioluminescent leptospires, which would permit in vivo visualization and investigation of host defense mechanisms during infection, have been unsuccessful. Using a firefly luciferase cassette and random transposition tools, we constructed bioluminescent chromosomal transformants in saprophytic and pathogenic leptospires. The kinetics of leptospiral dissemination in mice, after intraperitoneal inoculation with a pathogenic transformant, was tracked by bioluminescence using live imaging. For infective doses of 106 to 107 bacteria, we observed dissemination and exponential growth of leptospires in the blood, followed by apparent clearance of bacteria. However, with 2108 bacteria, the septicemia led to the death of mice within 3 days post-infection. In surviving mice, one week after infection, pathogenic leptospires reemerged only in the kidneys, where they multiplied and reached a steady state, leading to a sustained chronic renal infection. These experiments reveal that a fraction of the leptospiral population escapes the potent blood defense, and colonizes a defined number of niches in the kidneys, proportional to the infective dose. Antibiotic treatments failed to eradicate leptospires that colonized the kidneys, although they were effective against L. interrogans if administered before or early after infection. To conclude, mice infected with bioluminescent L. interrogans proved to be a novel model to study both acute and chronic leptospirosis, and revealed that, in the kidneys, leptospires are protected from antibiotics. These bioluminescent leptospires represent a powerful new tool to challenge mice treated with drugs or vaccines, and test the survival, dissemination, and transmission of leptospires between environment and hosts. PMID:25474719

  13. Subcutaneous administration of D-luciferin is an effective alternative to intraperitoneal injection in bioluminescence imaging of xenograft tumors in nude mice

    Khalil, Ashraf A.; Mark J. Jameson; Broaddus, William C.; Chung, Theodore D.; Sarah E. Golding; Dever, Seth M.; Rosenberg, Elisabeth; Valerie, Kristoffer

    2013-01-01

    Currently, intraperitoneal (IP) injection of D-luciferin is the preferred method of providing substrate for bioluminescence imaging (BLI); however it has a failure rate of 3–10% due to accidental intestinal injection. The present study evaluates the quality of BLI after subcutaneous (SC) injection of D-luciferin and demonstrates the effectiveness of SC injection in anatomically disparate tumor models. Mice bearing luciferase-expressing tumors underwent BLI after SC or IP injection of D-lucife...

  14. Susceptibility of the wild-derived inbred CAST/Ei mouse to infection by orthopoxviruses analyzed by live bioluminescence imaging

    Americo, Jeffrey L.; Sood, Cindy L.; Cotter, Catherine A.; Vogel, Jodi L.; Kristie, Thomas M.; Moss, Bernard, E-mail: bmoss@nih.gov; Earl, Patricia L., E-mail: pearl@nih.gov

    2014-01-20

    Classical inbred mice are extensively used for virus research. However, we recently found that some wild-derived inbred mouse strains are more susceptible than classical strains to monkeypox virus. Experiments described here indicated that the 50% lethal dose of vaccinia virus (VACV) and cowpox virus (CPXV) were two logs lower in wild-derived inbred CAST/Ei mice than classical inbred BALB/c mice, whereas there was little difference in the susceptibility of the mouse strains to herpes simplex virus. Live bioluminescence imaging was used to follow spread of pathogenic and attenuated VACV strains and CPXV virus from nasal passages to organs in the chest and abdomen of CAST/Ei mice. Luminescence increased first in the head and then simultaneously in the chest and abdomen in a dose-dependent manner. The spreading kinetics was more rapid with VACV than CPXV although the peak photon flux was similar. These data suggest advantages of CAST/Ei mice for orthopoxvirus studies. - Highlights: • Wild-derived inbred CAST/Ei mice are susceptible to vaccinia virus and cowpox virus. • Morbidity and mortality from orthopoxviruses are greater in CAST/Ei than BALB/c mice. • Morbidity and mortality from herpes simplex virus type 1 are similar in both mice. • Imaging shows virus spread from nose to lungs, abdominal organs and brain. • Vaccinia virus spreads more rapidly than cowpox virus.

  15. Susceptibility of the wild-derived inbred CAST/Ei mouse to infection by orthopoxviruses analyzed by live bioluminescence imaging

    Classical inbred mice are extensively used for virus research. However, we recently found that some wild-derived inbred mouse strains are more susceptible than classical strains to monkeypox virus. Experiments described here indicated that the 50% lethal dose of vaccinia virus (VACV) and cowpox virus (CPXV) were two logs lower in wild-derived inbred CAST/Ei mice than classical inbred BALB/c mice, whereas there was little difference in the susceptibility of the mouse strains to herpes simplex virus. Live bioluminescence imaging was used to follow spread of pathogenic and attenuated VACV strains and CPXV virus from nasal passages to organs in the chest and abdomen of CAST/Ei mice. Luminescence increased first in the head and then simultaneously in the chest and abdomen in a dose-dependent manner. The spreading kinetics was more rapid with VACV than CPXV although the peak photon flux was similar. These data suggest advantages of CAST/Ei mice for orthopoxvirus studies. - Highlights: • Wild-derived inbred CAST/Ei mice are susceptible to vaccinia virus and cowpox virus. • Morbidity and mortality from orthopoxviruses are greater in CAST/Ei than BALB/c mice. • Morbidity and mortality from herpes simplex virus type 1 are similar in both mice. • Imaging shows virus spread from nose to lungs, abdominal organs and brain. • Vaccinia virus spreads more rapidly than cowpox virus

  16. Observations of in situ deep-sea marine bioluminescence with a high-speed, high-resolution sCMOS camera

    Phillips, Brennan T.; Gruber, David F.; Vasan, Ganesh; Roman, Christopher N.; Pieribone, Vincent A.; Sparks, John S.

    2016-05-01

    Observing and measuring marine bioluminescence in situ presents unique challenges, characterized by the difficult task of approaching and imaging weakly illuminated bodies in a three-dimensional environment. To address this problem, a scientific complementary-metal-oxide-semiconductor (sCMOS) microscopy camera was outfitted for deep-sea imaging of marine bioluminescence. This system was deployed on multiple platforms (manned submersible, remotely operated vehicle, and towed body) in three oceanic regions (Western Tropical Pacific, Eastern Equatorial Pacific, and Northwestern Atlantic) to depths up to 2500 m. Using light stimulation, bioluminescent responses were recorded at high frame rates and in high resolution, offering unprecedented low-light imagery of deep-sea bioluminescence in situ. The kinematics of light production in several zooplankton groups was observed, and luminescent responses at different depths were quantified as intensity vs. time. These initial results signify a clear advancement in the bioluminescent imaging methods available for observation and experimentation in the deep-sea.

  17. Boosting bioluminescence neuroimaging: an optimized protocol for brain studies.

    Aswendt, Markus; Adamczak, Joanna; Couillard-Despres, Sebastien; Hoehn, Mathias

    2013-01-01

    Bioluminescence imaging is widely used for optical cell tracking approaches. However, reliable and quantitative bioluminescence of transplanted cells in the brain is highly challenging. In this study we established a new bioluminescence imaging protocol dedicated for neuroimaging, which increases sensitivity especially for noninvasive tracking of brain cell grafts. Different D-Luciferin concentrations (15, 150, 300 and 750 mg/kg), injection routes (i.v., i.p., s.c.), types of anesthesia (Isoflurane, Ketamine/Xylazine, Pentobarbital) and timing of injection were compared using DCX-Luc transgenic mice for brain specific bioluminescence. Luciferase kinetics was quantitatively evaluated for maximal photon emission, total photon emission and time-to-peak. Photon emission followed a D-Luciferin dose-dependent relation without saturation, but with delay in time-to-peak increasing for increasing concentrations. The comparison of intravenous, subcutaneous and intraperitoneal substrate injection reflects expected pharmacokinetics with fastest and highest photon emission for intravenous administration. Ketamine/Xylazine and Pentobarbital anesthesia showed no significant beneficial effect on maximal photon emission. However, a strong difference in outcome was observed by injecting the substrate pre Isoflurane anesthesia. This protocol optimization for brain specific bioluminescence imaging comprises injection of 300 mg/kg D-Luciferin pre Isoflurane anesthesia as an efficient and stable method with a signal gain of approx. 200% (compared to 150 mg/kg post Isoflurane). Gain in sensitivity by the novel imaging protocol was quantitatively assessed by signal-to-noise calculations of luciferase-expressing neural stem cells grafted into mouse brains (transplantation of 3,000-300,000 cells). The optimized imaging protocol lowered the detection limit from 6,000 to 3,000 cells by a gain in signal-to-noise ratio. PMID:23405190

  18. A Dual-Color Far-Red to Near-Infrared Firefly Luciferin Analogue Designed for Multiparametric Bioluminescence Imaging**

    Jathoul, A. P.; Grounds, H.; Anderson, J.; Pule, M. A.

    2014-01-01

    Red-shifted bioluminescent emitters allow improved in vivo tissue penetration and signal quantification, and have led to the development of beetle luciferin analogues that elicit red-shifted bioluminescence with firefly luciferase. However, unlike natural luciferin, none have been shown to emit different colors with different luciferases. We have synthesized and tested the first dual color, far-red to near infrared (nIR) emitting analogue of beetle luciferin, which akin to natural luciferin e...

  19. Bio-luminescent imaging and characterization of organ-specific metastasis of human cancer in NOD/SCID mice

    Chun, Nicole A. L.; Murakami, Takashi

    2010-02-01

    Many clinical evidences demonstrate that the sites of distant metastasis are not random and certain malignant tumors show a tendency to develop metastases in specific organs (e.g., brain, liver, and lungs). However, an appropriate animal model to characterize the metastatic nature of transplantable human cancer cell lines has not been reported well. Recent advances in bio-luminescent imaging (BLI) technologies have facilitated the quantitative analysis of various cellular processes in vivo. To visualize the fate of tumor progression in the living mice, we are constructing a luciferaseexpressing human cancer cell library (including melanoma, colon, breast, and prostate cancer). Herein we demonstrate that the BLI technology in couple with a fine ultrasonic guidance realizes cancer cell-type dependent metastasis to the specific organs. For example, some melanoma cell lines showed frequent metastasis to brain, lungs, and lymph nodes in the mouse model. Notably, reflecting the clinical features of melanoma, breast, and prostate cancer, some of the cell lines showed preferential metastasis to the brain. Moreover, these cellular resources for BLI allow a high throughput screening for potential anti-cancer drugs. Thus, this BLI-mediated additional strategy with the luciferase-expressing cancer cell resources should promote many translational studies for human cancer therapy.

  20. Evaluation of bioluminescent imaging for noninvasive monitoring of colorectal cancer progression in the liver and its response to immunogene therapy

    Gonzalez-Aparicio Manuela

    2009-01-01

    Full Text Available Abstract Background Bioluminescent imaging (BLI is based on the detection of light emitted by living cells expressing a luciferase gene. Stable transfection of luciferase in cancer cells and their inoculation into permissive animals allows the noninvasive monitorization of tumor progression inside internal organs. We have applied this technology for the development of a murine model of colorectal cancer involving the liver, with the aim of improving the pre-clinical evaluation of new anticancer therapies. Results A murine colon cancer cell line stably transfected with the luciferase gene (MC38Luc1 retains tumorigenicity in immunocompetent C57BL/6 animals. Intrahepatic inoculation of MC38Luc1 causes progressive liver infiltration that can be monitored by BLI. Compared with ultrasonography (US, BLI is more sensitive, but accurate estimation of tumor mass is impaired in advanced stages. We applied BLI to evaluate the efficacy of an immunogene therapy approach based on the liver-specific expression of the proinflammatory cytokine interleukin-12 (IL-12. Individualized quantification of light emission was able to determine the extent and duration of antitumor responses and to predict long-term disease-free survival. Conclusion We show that BLI is a rapid, convenient and safe technique for the individual monitorization of tumor progression in the liver. Evaluation of experimental treatments with complex mechanisms of action such as immunotherapy is possible using this technology.

  1. Subcutaneous administration of D-luciferin is an effective alternative to intraperitoneal injection in bioluminescence imaging of xenograft tumors in nude mice

    Khalil, Ashraf A.; Jameson, Mark J.; Broaddus, William C.; Chung, Theodore D.; Golding, Sarah E.; Dever, Seth M.; Rosenberg, Elisabeth; Valerie, Kristoffer

    2014-01-01

    Currently, intraperitoneal (IP) injection of D-luciferin is the preferred method of providing substrate for bioluminescent imaging (BLI); however it has a failure rate of 3–10% due to accidental intestinal injection. The present study evaluates the quality of BLI after subcutaneous (SC) injection of D-luciferin and demonstrates the effectiveness of SC injection in anatomically disparate tumor models. Mice bearing luciferase-expressing tumors underwent BLI after SC or IP injection of D-luciferin. The average time to maximal luminescence was 6 min (range 5–9 min) after SC injection and 8 min (range 5–8 min) after IP injection. Within 7 minutes of injection, SC and IP routes yielded similar luminescence in subcutaneous, intracranial, tongue, and lung xenograft tumor models. In a model of combined subcutaneous and intracranial xenografts, SC injection resulted in proportional luminescence at all sites, confirming that preferential delivery of substrate does not occur. While tumors were occasionally not visualized with IP injection, all tumors were visualized reliably with SC injection. Thus, SC injection of D-luciferin is a convenient and effective alternative to IP injection for BLI in nude mice. It may be a preferable approach, particularly for tumors with weaker signals and/or when greater precision is required. PMID:25392739

  2. Application of photosensitive devices to bioluminescence studies

    Reynolds, G.T.

    1978-01-01

    A brief review is given of some results obtained by the application of image intensification to studies of bioluminescence. The system consists of an image intensifier placed at the output of a suitable microscope, so that the image from the microscope falls on the intensifier cathode. The photon gain of the intensifier can be varied from a few thousand to one million. The output of the intensifier is recorded either on film or, in most applications to date, by means of a TV vidicon. The TV system permits display on a monitor in real time and simultaneous recording on magnetic tape for subsequent playback and analysis. It also provides time resolution for dynamic studies. Results are summarized for in vivo observations on Noctiluca miliaris, Obelia, Renilla, and Mnemiopsis leidyi. Utilization of the luminescence of aequorin in the presence of Ca/sup 2 +/ has been directed to observations on amoebae and the egg of the Medaka fish. Studies at the molecular level have been made by means of the spectral distribution of the output light. In these, the output of a fast input lens grating spectrometer is focused on the image intensifier cathode. Thus the entire visible spectrum of an in vivo bioluminescent flash can be intensified and recorded on film by photographing the output. The film is then analyzed by means of a digitized densitometer, and a computer program corrects the observed spectrum for system non-linearities and non-uniformities. In this way, the in vivo spectra of 15 bioluminescent species have been recorded.

  3. GMO detection using a bioluminescent real time reporter (BART of loop mediated isothermal amplification (LAMP suitable for field use

    Kiddle Guy

    2012-04-01

    Full Text Available Abstract Background There is an increasing need for quantitative technologies suitable for molecular detection in a variety of settings for applications including food traceability and monitoring of genetically modified (GM crops and their products through the food processing chain. Conventional molecular diagnostics utilising real-time polymerase chain reaction (RT-PCR and fluorescence-based determination of amplification require temperature cycling and relatively complex optics. In contrast, isothermal amplification coupled to a bioluminescent output produced in real-time (BART occurs at a constant temperature and only requires a simple light detection and integration device. Results Loop mediated isothermal amplification (LAMP shows robustness to sample-derived inhibitors. Here we show the applicability of coupled LAMP and BART reactions (LAMP-BART for determination of genetically modified (GM maize target DNA at low levels of contamination (0.1-5.0% GM using certified reference material, and compare this to RT-PCR. Results show that conventional DNA extraction methods developed for PCR may not be optimal for LAMP-BART quantification. Additionally, we demonstrate that LAMP is more tolerant to plant sample-derived inhibitors, and show this can be exploited to develop rapid extraction techniques suitable for simple field-based qualitative tests for GM status determination. We also assess the effect of total DNA assay load on LAMP-BART quantitation. Conclusions LAMP-BART is an effective and sensitive technique for GM detection with significant potential for quantification even at low levels of contamination and in samples derived from crops such as maize with a large genome size. The resilience of LAMP-BART to acidic polysaccharides makes it well suited to rapid sample preparation techniques and hence to both high throughput laboratory settings and to portable GM detection applications. The impact of the plant sample matrix and genome loading within a reaction must be controlled to ensure quantification at low target concentrations.

  4. Boosting Bioluminescence Neuroimaging: An Optimized Protocol for Brain Studies

    Aswendt, Markus; Adamczak, Joanna; Couillard-Despres, Sebastien; Hoehn, Mathias

    2013-01-01

    Bioluminescence imaging is widely used for optical cell tracking approaches. However, reliable and quantitative bioluminescence of transplanted cells in the brain is highly challenging. In this study we established a new bioluminescence imaging protocol dedicated for neuroimaging, which increases sensitivity especially for noninvasive tracking of brain cell grafts. Different D-Luciferin concentrations (15, 150, 300 and 750 mg/kg), injection routes (iv, ip, sc), types of anesthesia (Isoflurane...

  5. In vivo bioluminescence imaging to evaluate systemic and topical antibiotics against community-acquired methicillin-resistant Staphylococcus aureus-infected skin wounds in mice.

    Guo, Yi; Ramos, Romela Irene; Cho, John S; Donegan, Niles P; Cheung, Ambrose L; Miller, Lloyd S

    2013-02-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) frequently causes skin and soft tissue infections, including impetigo, cellulitis, folliculitis, and infected wounds and ulcers. Uncomplicated CA-MRSA skin infections are typically managed in an outpatient setting with oral and topical antibiotics and/or incision and drainage, whereas complicated skin infections often require hospitalization, intravenous antibiotics, and sometimes surgery. The aim of this study was to develop a mouse model of CA-MRSA wound infection to compare the efficacy of commonly used systemic and topical antibiotics. A bioluminescent USA300 CA-MRSA strain was inoculated into full-thickness scalpel wounds on the backs of mice and digital photography/image analysis and in vivo bioluminescence imaging were used to measure wound healing and the bacterial burden. Subcutaneous vancomycin, daptomycin, and linezolid similarly reduced the lesion sizes and bacterial burden. Oral linezolid, clindamycin, and doxycycline all decreased the lesion sizes and bacterial burden. Oral trimethoprim-sulfamethoxazole decreased the bacterial burden but did not decrease the lesion size. Topical mupirocin and retapamulin ointments both reduced the bacterial burden. However, the petrolatum vehicle ointment for retapamulin, but not the polyethylene glycol vehicle ointment for mupirocin, promoted wound healing and initially increased the bacterial burden. Finally, in type 2 diabetic mice, subcutaneous linezolid and daptomycin had the most rapid therapeutic effect compared with vancomycin. Taken together, this mouse model of CA-MRSA wound infection, which utilizes in vivo bioluminescence imaging to monitor the bacterial burden, represents an alternative method to evaluate the preclinical in vivo efficacy of systemic and topical antimicrobial agents. PMID:23208713

  6. Self-illuminating quantum dots for non-invasive bioluminescence imaging of mammalian

    Background: The fertility performance of animals is still a mystery and the full comprehension of mammalian gametes maturation and early embryonic development remains to be elucidated. The recent development in nanotechnology offers a new opportunity for real-time study of reproductive cells in thei...

  7. Spectrally resolved bioluminescence tomography using the reciprocity approach

    Dehghani, Hamid; Davis, Scott C.; Pogue, Brian W.

    2008-01-01

    Spectrally resolved bioluminescence optical tomography is an approach to recover images of, for example, Luciferase activity within a volume using multiwavelength emission data from internal bioluminescence sources. The underlying problem of uniqueness associated with nonspectrally resolved intensity-based bioluminescence tomography is demonstrated and it is shown that using a non-negative constraint inverse algorithm, an accurate solution for the source distribution can be calculated from th...

  8. Quantum dot-NanoLuc bioluminescence resonance energy transfer enables tumor imaging and lymph node mapping in vivo.

    Kamkaew, Anyanee; Sun, Haiyan; England, Christopher G; Cheng, Liang; Liu, Zhuang; Cai, Weibo

    2016-05-19

    A small luciferase protein (Nluc) was conjugated to QDs as a bioluminescence resonance energy transfer (BRET) pair. The conjugate showed 76% BRET efficiency and lymph node mapping was successfully performed. The cRGD peptide was conjugated to QD-Nluc for tumor targeting. The self-illuminating QD-Nluc showed excellent energy transfer in a living system and offered an optimal tumor-to-background ratio (>85). PMID:27157466

  9. Molecular imaging of lentiviral vector-mediated reporter gene expression with positron emission tomography and bioluminescence imaging

    Deroose, Christophe

    2007-01-01

    Table of Contents Dankwoord 1 Table of Contents 5 Abbreviations 9 Chapter 1: General Introduction 13 1. Imaging Modalities 14 1.1. Radionuclide Imaging Techniques 15 1.1.1. Single Photon Emission Computed Tomography (SPECT) 15 1.1.2. Positron Emission Tomography 16 1.2. Magnetic Resonance Imaging and Spectroscopy 16 1.2.1. Magnetic Resonance Imaging (MRI) 16 1.2.2. Magnetic Resonance Spectroscopy (MRS) 17 1.3. Optical Imaging Strategies 17 1.3.1. Fluore...

  10. Time encoded radiation imaging

    Marleau, Peter; Brubaker, Erik; Kiff, Scott

    2014-10-21

    The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.

  11. Effect of electromagnetic fields on the bacteria bioluminescent activity

    The effect of electromagnetic field with frequency from 36.2 to 55.9 GHz on bioluminescence activity of bacterium were investigated. Electromagnetic field results in decrease of bioluminescence, which depends from frequency. The electromagnetic field adaptation time is higher of intrinsic time parameters of bioluminescence system. The effect has nonthermal nature. It is suggested that electromagnetic field influence connects with structure rearrangements near cell emitter. 8 refs.; 3 figs

  12. Uniqueness theorems in bioluminescence tomography.

    Wang, Ge; Li, Yi; Jiang, Ming

    2004-08-01

    Motivated by bioluminescent imaging needs for studies on gene therapy and other applications in the mouse models, a bioluminescence tomography (BLT) system is being developed in the University of Iowa. While the forward imaging model is described by the well-known diffusion equation, the inverse problem is to recover an internal bioluminescent source distribution subject to Cauchy data. Our primary goal in this paper is to establish the solution uniqueness for BLT under practical constraints despite the ill-posedness of the inverse problem in the general case. After a review on the inverse source literature, we demonstrate that in the general case the BLT solution is not unique by constructing the set of all the solutions to this inverse problem. Then, we show the uniqueness of the solution in the case of impulse sources. Finally, we present our main theorem that solid/hollow ball sources can be uniquely determined up to nonradiating sources. For better readability, the exact conditions for and rigorous proofs of the theorems are given in the Appendices. Further research directions are also discussed. PMID:15377096

  13. Formulation of photon diffusion from spherical bioluminescent sources in an infinite homogeneous medium

    Wang Lihong V

    2004-05-01

    Full Text Available Abstract Background The bioluminescent enzyme firefly luciferase (Luc or variants of green fluorescent protein (GFP in transformed cells can be effectively used to reveal molecular and cellular features of neoplasia in vivo. Tumor cell growth and regression in response to various therapies can be evaluated by using bioluminescent imaging. In bioluminescent imaging, light propagates in highly scattering tissue, and the diffusion approximation is sufficiently accurate to predict the imaging signal around the biological tissue. The numerical solutions to the diffusion equation take large amounts of computational time, and the studies for its analytic solutions have attracted more attention in biomedical engineering applications. Methods Biological tissue is a turbid medium that both scatters and absorbs photons. An accurate model for the propagation of photons through tissue can be adopted from transport theory, and its diffusion approximation is applied to predict the imaging signal around the biological tissue. The solution to the diffusion equation is formulated by the convolution between its Green's function and source term. The formulation of photon diffusion from spherical bioluminescent sources in an infinite homogeneous medium can be obtained to accelerate the forward simulation of bioluminescent phenomena. Results The closed form solutions have been derived for the time-dependent diffusion equation and the steady-state diffusion equation with solid and hollow spherical sources in a homogeneous medium, respectively. Meanwhile, the relationship between solutions with a solid sphere source and ones with a surface sphere source is obtained. Conclusion We have formulated solutions for the diffusion equation with solid and hollow spherical sources in an infinite homogeneous medium. These solutions have been verified by Monte Carlo simulation for use in biomedical optical imaging studies. The closed form solution is highly accurate and more computationally efficient in biomedical engineering applications. By using our analytic solutions for spherical sources, we can better predict bioluminescent signals and better understand both the potential for, and the limitations of, bioluminescent tomography in an idealized case. The formulas are particularly valuable for furthering the development of bioluminescent tomography.

  14. Bioluminescence in the high Arctic during the polar night

    Berge, Jørgen; Båtnes, Anna Solvang; Johnsen, Geir; Blackwell, Susan; Moline, Mark A.

    2012-01-01

    This study examines the composition and activity of the planktonic community during the polar night in the high Arctic Kongsfjord, Svalbard. Our results are the first published evidence of bioluminescence among zooplankton during the Arctic polar night. The observations were collected by a bathyphotometer detecting bioluminescence, integrated into an autonomous underwater vehicle, to determine the concentration and intensity of bioluminescent flashes as a function of time of day and depth. To...

  15. Luciferase expression and bioluminescence does not affect tumor cell growth in vitro or in vivo

    Rasko John EJ

    2010-11-01

    Full Text Available Abstract Live animal imaging is becoming an increasingly common technique for accurate and quantitative assessment of tumor burden over time. Bioluminescence imaging systems rely on a bioluminescent signal from tumor cells, typically generated from expression of the firefly luciferase gene. However, previous reports have suggested that either a high level of luciferase or the resultant light reaction produced upon addition of D-luciferin substrate can have a negative influence on tumor cell growth. To address this issue, we designed an expression vector that allows simultaneous fluorescence and luminescence imaging. Using fluorescence activated cell sorting (FACS, we generated clonal cell populations from a human breast cancer (MCF-7 and a mouse melanoma (B16-F10 cell line that stably expressed different levels of luciferase. We then compared the growth capabilities of these clones in vitro by MTT proliferation assay and in vivo by bioluminescence imaging of tumor growth in live mice. Surprisingly, we found that neither the amount of luciferase nor biophotonic activity was sufficient to inhibit tumor cell growth, in vitro or in vivo. These results suggest that luciferase toxicity is not a necessary consideration when designing bioluminescence experiments, and therefore our approach can be used to rapidly generate high levels of luciferase expression for sensitive imaging experiments.

  16. Bioluminescence imaging of point sources implanted in small animals post mortem: evaluation of a method for estimating source strength and depth

    The performance of a simple approach for the in vivo reconstruction of bioluminescent point sources in small animals was evaluated. The method uses the diffusion approximation as a forward model of light propagation from a point source in a homogeneous tissue to find the source depth and power. The optical properties of the tissue are estimated from reflectance images obtained at the same location on the animal. It was possible to localize point sources implanted in mice, 2-8 mm deep, to within 1 mm. The same performance was achieved for sources implanted in rat abdomens when the effects of tissue surface curvature were eliminated. The source power was reconstructed within a factor of 2 of the true power for the given range of depths, even though the apparent brightness of the source varied by several orders of magnitude. The study also showed that reconstructions using optical properties measured in situ were superior to those based on data in the literature

  17. In vivo functional calcium imaging of induced or spontaneous activity in the fly brain using a GFP-apoaequorin-based bioluminescent approach.

    Minocci, Daiana; Carbognin, Elena; Murmu, Meena Sriti; Martin, Jean-Ren

    2013-07-01

    Different optical imaging techniques have been developed to study neuronal activity with the goal of deciphering the neural code underlying neurophysiological functions. Because of several constraints inherent in these techniques as well as difficulties interpreting the results, the majority of these studies have been dedicated more to sensory modalities than to the spontaneous activity of the central brain. Recently, a novel bioluminescence approach based on GFP-aequorin (GA) (GFP: Green fluorescent Protein), has been developed, allowing us to functionally record in-vivo neuronal activity. Taking advantage of the particular characteristics of GA, which does not require light excitation, we report that we can record induced and/or the spontaneous Ca(2+)-activity continuously over long periods. Targeting GA to the mushrooms-bodies (MBs), a structure implicated in learning/memory and sleep, we have shown that GA is sensitive enough to detect odor-induced Ca(2+)-activity in Kenyon cells (KCs). It has been possible to reveal two particular peaks of spontaneous activity during overnight recording in the MBs. Other peaks of spontaneous activity have been recorded in flies expressing GA pan-neurally. Similarly, expression in the glial cells has revealed that these cells exhibit a cell-autonomous Ca(2+)-activity. These results demonstrate that bioluminescence imaging is a useful tool for studying Ca(2+)-activity in neuronal and/or glial cells and for functional mapping of the neurophysiological processes in the fly brain. These findings provide a framework for investigating the biological meaning of spontaneous neuronal activity. This article is part of a Special Issue entitled: 12th European Symposium on Calcium. PMID:23287020

  18. High throughput and quantitative approaches for measuring circadian rhythms in cyanobacteria using bioluminescence

    Shultzaberger, Ryan K.; Paddock, Mark L.; Katsuki, Takeo; Greenspan, Ralph J.; Golden, Susan S.

    2016-01-01

    The temporal measurement of a bioluminescent reporter has proven to be one of the most powerful tools for characterizing circadian rhythms in the cyanobacterium Synechococcus elongatus. Primarily, two approaches have been used to automate this process: (1) detection of cell culture bioluminescence in 96-well plates by a photomultiplier tube-based plate-cycling luminometer (TopCount Microplate Scintillation and Luminescence Counter, Perkin Elmer) and (2) detection of individual colony bioluminescence by iteratively rotating a Petri dish under a cooled CCD camera using a computer-controlled turntable. Each approach has distinct advantages. The TopCount provides a more quantitative measurement of bioluminescence, enabling the direct comparison of clock output levels among strains. The computer-controlled turntable approach has a shorter set-up time and greater throughput, making it a more powerful phenotypic screening tool. While the latter approach is extremely useful, only a few labs have been able to build such an apparatus because of technical hurdles involved in coordinating and controlling both the camera and the turntable, and in processing the resulting images. This protocol provides instructions on how to construct, use, and process data from a computer-controlled turntable to measure the temporal changes in bioluminescence of individual cyanobacterial colonies. Furthermore, we describe how to prepare samples for use with the TopCount to minimize experimental noise, and generate meaningful quantitative measurements of clock output levels for advanced analysis. PMID:25662451

  19. In vivo bioluminescence tomography with a blocking-off finite-difference SP3 method and MRI∕CT coregistration

    Klose, Alexander D.; Beattie, Bradley J.; Dehghani, Hamid; Vider, Lena; Le, Carl; Ponomarev, Vladimir; Blasberg, Ronald

    2009-01-01

    Purpose: Bioluminescence imaging is a research tool for studying gene expression levels in small animal models of human disease. Bioluminescence light, however, is strongly scattered in biological tissue and no direct image of the light-emitting reporter probe’s location can be obtained. Therefore, the authors have developed a linear image reconstruction method for bioluminescence tomography (BLT) that recovers the three-dimensional spatial bioluminescent source distribution in small animals.

  20. Stimulated bioluminescence by fluid shear stress associated with pipe flow

    Cao Jing; Wang Jiangan; Wu Ronghua, E-mail: caojing981@126.com [Col. of Electronic Eng., Naval University of Engineering, Wuhan 430033 (China)

    2011-01-01

    Dinoflagellate can be stimulated bioluminescence by hydrodynamic agitation. Two typical dinoflagellate (Lingulodinium polyedrum and Pyrocystis noctiluca) was choosed to research stimulated bioluminescence. The bioluminescence intensity and shear stress intensity were measured using fully developed pipe flow. There is shear stress threshold to agitate organism bioluminescence. From these experiment, the response thresholds of the stimulated bioluminscence always occurred in laminar flows at a shear stress level of 0.6-3 dyn/cm{sup 2}. At the same time, the spectral characteristc of dinoflagellate was recorded, the wavelength of them is about 470nm, and the full width at half maximum is approximate 30nm.

  1. Stimulated bioluminescence by fluid shear stress associated with pipe flow

    Dinoflagellate can be stimulated bioluminescence by hydrodynamic agitation. Two typical dinoflagellate (Lingulodinium polyedrum and Pyrocystis noctiluca) was choosed to research stimulated bioluminescence. The bioluminescence intensity and shear stress intensity were measured using fully developed pipe flow. There is shear stress threshold to agitate organism bioluminescence. From these experiment, the response thresholds of the stimulated bioluminscence always occurred in laminar flows at a shear stress level of 0.6-3 dyn/cm2. At the same time, the spectral characteristc of dinoflagellate was recorded, the wavelength of them is about 470nm, and the full width at half maximum is approximate 30nm.

  2. Multispectral Bioluminescence Tomography: Methodology and Simulation

    Ge Wang

    2006-02-01

    Full Text Available Bioluminescent imaging has proven to be a valuable tool for monitoring physiological and pathological activities at cellular and molecular levels in living small animals. Using biological techniques, target cells can be tagged with reporters encoding several kinds of luciferase enzymes, which generate characteristic photons in a wide spectrum covering the infrared range. Part of the diffused light can reach the body surface of the small animal, be separated into several spectral bands using appropriate filters, and collected by a sensitive CCD camera. Here we present a bioluminescence tomography (BLT method for a bioluminescent source reconstruction from multispectral data measured on the external surface, and demonstrate the advantages of multispectral BLT in a numerical study using a heterogeneous mouse chest phantom. The results show that the multispectral approach significantly improves the accuracy and stability of the BLT reconstruction even if the data are highly noisy.

  3. Lighting up bioluminescence with coelenterazine: strategies and applications.

    Jiang, Tianyu; Du, Lupei; Li, Minyong

    2016-04-13

    Bioluminescence-based techniques, such as bioluminescence imaging, BRET and dual-luciferase reporter assay systems, have been widely used to examine a myriad of biological processes. Coelenterazine (CTZ), a luciferin or light-producing compound found in bioluminescent organisms, has sparked great curiosity and interest in searching for analogues with improved photochemical properties. This review summarizes the current development of coelenterazine analogues, their bioluminescence properties, and the rational design of caged coelenterazine towards biotargets, as well as their applications in bioassays. It should be emphasized that the design of caged luciferins can provide valuable insight into detailed molecular processes in organisms and will be a trend in the development of bioluminescent molecules. PMID:27009907

  4. Let there be bioluminescence: development of a biophotonic imaging platform for in situ analyses of oral biofilms in animal models.

    Merritt, Justin; Senpuku, Hidenobu; Kreth, Jens

    2016-01-01

    In the current study, we describe a novel biophotonic imaging-based reporter system that is particularly useful for the study of virulence in polymicrobial infections and interspecies interactions within animal models. A suite of luciferase enzymes was compared using three early colonizing species of the human oral flora (Streptococcus mutans, Streptococcus gordonii and Streptococcus sanguinis) to determine the utility of the different reporters for multiplexed imaging studies in vivo. Using the multiplex approach, we were able to track individual species within a dual-species oral infection model in mice with both temporal and spatial resolution. We also demonstrate how biophotonic imaging of multiplexed luciferase reporters could be adapted for real-time quantification of bacterial gene expression in situ. By creating an inducible dual-luciferase expressing reporter strain of S.?mutans, we were able to exogenously control and measure expression of nlmAB (encoding the bacteriocin mutacin IV) within mice to assess its importance for the persistence ability of S.?mutans in the oral cavity. The imaging system described in the current study circumvents many of the inherent limitations of current animal model systems, which should now make it feasible to test hypotheses that were previously impractical to model. PMID:26119252

  5. Bioluminescent imaging of vaccinia virus infection in immunocompetent and immunodeficient rats as a model for human smallpox.

    Liu, Qiang; Fan, Changfa; Zhou, Shuya; Guo, Yanan; Zuo, Qin; Ma, Jian; Liu, Susu; Wu, Xi; Peng, Zexu; Fan, Tao; Guo, Chaoshe; Shen, Yuelei; Huang, Weijin; Li, Baowen; He, Zhengming; Wang, Youchun

    2015-01-01

    Due to the increasing concern of using smallpox virus as biological weapons for terrorist attack, there is renewed interest in studying the pathogenesis of human smallpox and development of new therapies. Animal models are highly demanded for efficacy and safety examination of new vaccines and therapeutic drugs. Here, we demonstrated that both wild type and immunodeficient rats infected with an engineered vaccinia virus carrying Firefly luciferase reporter gene (rTV-Fluc) could recapitulate infectious and clinical features of human smallpox. Vaccinia viral infection in wild type Sprague-Dawley (SD) rats displayed a diffusible pattern in various organs, including liver, head and limbs. The intensity of bioluminescence generated from rTV-Fluc correlated well with viral loads in tissues. Moreover, neutralizing antibodies had a protective effect against virus reinfection. The recombination activating gene 2 (Rag2) knockout rats generated by transcription activator-like effector nucleases (TALENs) technology were further used to examine the infectivity of the rTV-Fluc in immunodeficient populations. Here we demonstrated that Rag2-/- rats were more susceptible to rTV-Fluc than SD rats with a slower virus clearance rate. Therefore, the rTV-Fluc/SD rats and rTV-Fluc/Rag2-/- rats are suitable visualization models, which recapitulate wild type or immunodeficient populations respectively, for testing human smallpox vaccine and antiviral drugs. PMID:26235050

  6. 6-hydroxydopamine-induced Parkinson's disease-like degeneration generates acute microgliosis and astrogliosis in the nigrostriatal system but no bioluminescence imaging-detectable alteration in adult neurogenesis.

    Fricke, Inga B; Viel, Thomas; Worlitzer, Maik M; Collmann, Franziska M; Vrachimis, Alexis; Faust, Andreas; Wachsmuth, Lydia; Faber, Cornelius; Dollé, Frédéric; Kuhlmann, Michael T; Schäfers, Klaus; Hermann, Sven; Schwamborn, Jens C; Jacobs, Andreas H

    2016-05-01

    Parkinson's disease is a slowly progressing neurodegenerative disorder caused by loss of dopaminergic neurons in the substantia nigra (SN), leading to severe impairment in motor and non-motor functions. Endogenous subventricular zone (SVZ) neural stem cells constantly give birth to new cells that might serve as a possible source for regeneration in the adult brain. However, neurodegeneration is accompanied by neuroinflammation and dopamine depletion, potentially compromising regeneration. We therefore employed in vivo imaging methods to study striatal deafferentation (N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-[(123) I]iodophenyl)nortropane single photon emission computed tomography, DaTscan(™) ) and neuroinflammation in the SN and striatum (N,N-diethyl-2-(2-(4-(2-[(18) F]fluoroethoxy)phenyl)-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)acetamide positron emission tomography, [(18) F]DPA-714 PET) in the intranigral 6-hydroxydopamine Parkinson's disease mouse model. Additionally, we transduced cells in the SVZ with a lentivirus encoding firefly luciferase and followed migration of progenitor cells in the SVZ-olfactory bulb axis via bioluminescence imaging under disease and control conditions. We found that activation of microglia in the SN is an acute process accompanying the degeneration of dopaminergic cell bodies in the SN. Dopaminergic deafferentation of the striatum does not influence the generation of doublecortin-positive neuroblasts in the SVZ, but generates chronic astrogliosis in the nigrostriatal system. PMID:26950181

  7. Nanostructured bioluminescent sensor for rapidly detecting thrombin.

    Chen, Longyan; Bao, Yige; Denstedt, John; Zhang, Jin

    2016-03-15

    Thrombin plays a key role in thrombosis and hemostasis. The abnormal level of thrombin in body fluids may lead to different diseases, such as rheumatoid arthritis, glomerulonephritis, etc. Detection of thrombin level in blood and/or urine is one of important methods for medical diagnosis. Here, a bioluminescent sensor is developed for non-invasively and rapidly detecting thrombin in urine. The sensor is assembled through conjugating gold nanoparticles (Au NPs) and a recombinant protein containing Renilla luciferase (pRluc) by a peptide, which is thrombin specific substrate. The luciferase-catalyzed bioluminescence can be quenched by peptide-conjugating Au NPs. In the presence of thrombin, the short peptide conjugating luciferase and Au NPs is digested and cut off, which results in the recovery of bioluminescence due to the release of luciferase from Au NPs. The bioluminescence intensity at 470 nm is observed, and increases with increasing concentration of thrombin. The bioluminescence intensity of this designed sensor is significantly recovered when the thrombin digestion time lasts for 10 min. In addition, a similar linear relationship between luminescence intensity and the concentration of thrombin is found in the range of 8 nM to 8 μM in both buffer and human urine spiked samples. The limit of detection is as low as 80 pM. It is anticipated that our nanosensor could be a promising tool for clinical diagnosis of thrombin in human urine. PMID:26397418

  8. Bioluminescent bioreporter integrated circuit

    Simpson, Michael L. (Knoxville, TN); Sayler, Gary S. (Blaine, TN); Paulus, Michael J. (Knoxville, TN)

    2000-01-01

    Disclosed are monolithic bioelectronic devices comprising a bioreporter and an OASIC. These bioluminescent bioreporter integrated circuit are useful in detecting substances such as pollutants, explosives, and heavy-metals residing in inhospitable areas such as groundwater, industrial process vessels, and battlefields. Also disclosed are methods and apparatus for environmental pollutant detection, oil exploration, drug discovery, industrial process control, and hazardous chemical monitoring.

  9. Space-Time Quantum Imaging

    Ronald E. Meyers

    2015-03-01

    Full Text Available We report on an experimental and theoretical investigation of quantum imaging where the images are stored in both space and time. Ghost images of remote objects are produced with either one or two beams of chaotic laser light generated by a rotating ground glass and two sensors measuring the reference field and bucket field at different space-time points. We further observe that the ghost images translate depending on the time delay between the sensor measurements. The ghost imaging experiments are performed both with and without turbulence. A discussion of the physics of the space-time imaging is presented in terms of quantum nonlocal two-photon analysis to support the experimental results. The theoretical model includes certain phase factors of the rotating ground glass. These experiments demonstrated a means to investigate the time and space aspects of ghost imaging and showed that ghost imaging contains more information per measured photon than was previously recognized where multiple ghost images are stored within the same ghost imaging data sets. This suggests new pathways to explore quantum information stored not only in multi-photon coincidence information but also in time delayed multi-photon interference. The research is applicable to making enhanced space-time quantum images and videos of moving objects where the images are stored in both space and time.

  10. A real-time bioluminescent HTS method for measuring protein kinase activity influenced neither by ATP concentration nor by luciferase inhibition.

    Lundin, Arne; Eriksson, Jonas

    2008-08-01

    The firefly luciferin-luciferase reaction has been used to set up an assay for protein kinase based on measuring ATP consumption rate as the first-order rate constant for the kinase reaction. The assay obviates the problems encountered with previous bioluminescent protein kinase assays such as interference with the luciferase reaction from library compounds, nonlinear standard curves, and limited dynamic ranges. In the assay described in the present paper luciferase and luciferin are present during the entire kinase reaction, and the light emission can be measured continuously. In an HTS situation the light emission is measured only twice, i.e., initially and after a predetermined time. After a fivefold reduction of the ATP concentration a Z' value of 0.96 was obtained. Light emission data from samples with kinase are normalized with light emission data from blanks without kinase. First-order rate constants for the kinase reaction calculated from normalized light emission are not affected by a moderate degree of inactivation of luciferase and luciferin during the measuring time. The constants have the same value at all ATP concentrations much lower than the K(m) of the luciferase and the kinase. These factors make the assay very robust and influenced neither by ATP concentration nor by luciferase inhibition. The measuring time depends on the kinase activity and can be varied from minutes to more than 8 h provided the kinase is stable and the evaporation of water from the wells is acceptable. The assay is linear with respect to kinase activity over three orders of magnitude. The new reagents also allowed us to determine K(m) values for ATP and for Kemptide. PMID:18532902

  11. Circadian regulation of bioluminescence in Gonyaulax involves translational control.

    Morse, D.; Milos, P M; Roux, E.; Hastings, J. W.

    1989-01-01

    A 10-fold circadian variation in the amount of luciferin binding protein (LBP) in the marine dinoflagellate Gonyaulax polyedra is reported. This protein binds and stabilizes luciferin, the bioluminescence substrate. In early night phase, when bioluminescence is increasing and LBP levels are rising in the cell, pulse labeling experiments show that LBP is being rapidly synthesized in vivo. At other times, the rate of LBP synthesis is at least 50 times lower, while the rate of synthesis of most ...

  12. Information-theoretic method for wavelength selection in bioluminescence tomography

    Basevi, Hector R. A.; Guggenheim, James A.; Dehghani, Hamid; Styles, Iain B.

    2013-06-01

    Practical imaging constraints restrict the number of wavelengths that can be measured in a single Biolumines- cence Tomography imaging session, but it is unclear which set of measurement wavelengths is optimal, in the sense of providing the most information about the bioluminescent source. Mutual Information was used to integrate knowledge of the type of bioluminescent source likely to be present, the optical properties of tissue and physics of light propagation, and the noise characteristics of the imaging system, in order to quantify the information contained in measurements at different sets of wavelengths. The approach was applied to a two-dimensional sim- ulation of Bioluminescence Tomography imaging of a mouse, and the results indicate that different wavelengths and sets of wavelengths contain different amounts of information. When imaging at a single wavelength, 580nm was found to be optimal, and when imaging at two wavelengths, 570nm and 580nm were found to be optimal. Examination of the dispersion of the posterior distributions for single wavelengths suggests that information regarding the location of the centre of the bioluminescence distribution is relatively independent of wavelength, whilst information regarding the width of the bioluminescence distribution is relatively wavelength specific.

  13. Rational and random mutagenesis of firefly luciferase to identify an efficient emitter of red bioluminescence

    Branchini, Bruce R.; Southworth, Tara L.; Khattak, Neelum F.; Murtiashaw, Martha H.; Fleet, Sarah E.

    2004-06-01

    Firefly luciferase, which emits yellow-green (557 nm) light, and the corresponding cDNA have been used successfully as a bioluminescence reporter of gene expression. One particularly exciting application is in the area of in vivo bioluminescence imaging. Our interest is in developing improved reagents by identifying Photinus pyralis luciferase mutants that efficiently emit red bioluminescence. In this way, the proven advantages of the P. pyralis protein can be combined with the potential advantages of a red-shifted emitter. Using site-directed mutagenesis techniques, we have identified many mutants emitting red bioluminescence. Unfortunately, these enzymes generally have significantly decreased bioluminescence activity. Interestingly, we discovered a mutation, Ile351Ala, that produced a moderate 16 nm red-shift, while maintaining excellent bioluminescence activity. We then undertook a random mutagenesis approach to identify luciferase mutants that emit further red-shifted bioluminescence with minimal loss of activity. Libraries of mutants were created using an error-prone PCR method and the Ile351Ala luciferase mutant as the template DNA. The libraries were screened by in vivo bacterial assays and the promising mutants were purified to enable accurate determination of bioluminescence emission spectra and total bioluminescence activity. We will report the characterization results, including the identification of the randomly altered amino acids, of several mutants that catalyze bioluminescence with emission maxima of approximately 600 nm.

  14. Bioluminescent organs of two deep-sea arrow worms, Eukrohnia fowleri and Caecosagitta macrocephala, with further observations on Bioluminescence in chaetognaths.

    Thuesen, Erik V; Goetz, Freya E; Haddock, Steven H D

    2010-10-01

    Bioluminescence in the deep-sea chaetognath Eukrohnia fowleri is reported for the first time, and behavioral, morphological, and chemical characteristics of bioluminescence in chaetognaths are examined. Until this study, the only known species of bioluminescent chaetognath was Caecosagitta macrocephala. The luminescent organ of that species is located on the ventral edge of each anterior lateral fin, whereas that of E. fowleri runs across the center of the tail fin on both dorsal and ventral sides. Scanning electron microscopy showed that the bioluminescent organs of both species consist of hexagonal chambers containing elongate ovoid particles-the organelles holding bioluminescent materials. No other luminous organism is known to use hexagonal packing to hold bioluminescent materials. Transmission electron microscopy of particles from C. macrocephala revealed a densely packed paracrystalline matrix punctuated by globular inclusions, which likely correspond to luciferin and luciferase, respectively. Both species use unique luciferases in conjunction with coelenterazine for light emission. Luciferase of C. macrocephala becomes inactive after 30 min, but luciferase of E. fowleri is highly stable. Although C. macrocephala has about 90 times fewer particles than E. fowleri, it has a similar bioluminescent capacity (total particle volume) due to its larger particle size. In situ observations of C. macrocephala from a remotely operated vehicle revealed that the luminous particles are released to form a cloud. The discovery of bioluminescence in a second chaetognath phylogenetically distant from the first highlights the importance of bioluminescence among deep-sea organisms. PMID:20972255

  15. Action of γ-radiation on bioluminescence of Noctiluca miliaris

    Results of the study in the action of various doses of irradiation on the bioluminescence of Noctiluca miliaris are presented. The doses are found that stimulate the bioluminescence and the dose - effect curves are obtained. It has been shown that stimulation of Noctiluca luminescence by γ-radiation is not of a constant character and extinguishes after a period of time determined by a dose rate

  16. Bioluminescence-based visualization of CD4 T cell dynamics using a T lineage-specific luciferase transgenic model1

    Zinn Kurt R

    2009-08-01

    Full Text Available Abstract Background Rapid clonal expansion of T cells occurs in response to antigenic challenges. The kinetics of the T cell response has previously been described using tissue-based studies performed at defined time points. Luciferase bioluminescence has recently been utilized for non-invasive analysis of in vivo biologic processes in real-time. Results We have created a novel transgenic mouse model (T-Lux using a human CD2 mini-gene to direct luciferase expression specifically to the T cell compartment. T-Lux T cells demonstrated normal homing patterns within the intact mouse and following adoptive transfer. Bioluminescent signal correlated with T cell numbers in the whole body images as well as within specific organ regions of interest. Following transfer into lymphopenic (RAG2-/- recipients, homeostatic proliferation of T-Lux T cells was visualized using bioluminescent imaging. Real-time bioluminescent analysis of CD4+ T cell antigen-specific responses enabled real-time comparison of the kinetics and magnitude of clonal expansion and contraction in the inductive lymph node and tissue site of antigen injection. T cell expansion was dose-dependent despite the presence of supraphysiologic numbers of OVA-specific OT-II transgenic TCR T-Lux T cells. CD4+ T cells subsequently underwent a rapid (34 day contraction phase in the draining lymph node, with a delayed contraction in the antigen delivery site, with bioluminescent signal diminished below initial levels, representing TCR clonal frequency control. Conclusion The T-Lux mouse provides a novel, efficient model for tracking in vivo aspects of the CD4+ T cell response to antigen, providing an attractive approach for studies directed at immunotherapy or vaccine design.

  17. Bioluminescent bacteria: lux genes as environmental biosensors

    Nunes-Halldorson Vânia da Silva; Duran Norma Letícia

    2003-01-01

    Bioluminescent bacteria are widespread in natural environments. Over the years, many researchers have been studying the physiology, biochemistry and genetic control of bacterial bioluminescence. These discoveries have revolutionized the area of Environmental Microbiology through the use of luminescent genes as biosensors for environmental studies. This paper will review the chronology of scientific discoveries on bacterial bioluminescence and the current applications of bioluminescence in env...

  18. Measurement of Bacterial Bioluminescence Intensity and Spectrum: Current Physical Techniques and Principles.

    Jia, Kun; Ionescu, Rodica Elena

    2016-01-01

    : Bioluminescence is light production by living organisms, which can be observed in numerous marine creatures and some terrestrial invertebrates. More specifically, bacterial bioluminescence is the "cold light" produced and emitted by bacterial cells, including both wild-type luminescent and genetically engineered bacteria. Because of the lively interplay of synthetic biology, microbiology, toxicology, and biophysics, different configurations of whole-cell biosensors based on bacterial bioluminescence have been designed and are widely used in different fields, such as ecotoxicology, food toxicity, and environmental pollution. This chapter first discusses the background of the bioluminescence phenomenon in terms of optical spectrum. Platforms for bacterial bioluminescence detection using various techniques are then introduced, such as a photomultiplier tube, charge-coupled device (CCD) camera, micro-electro-mechanical systems (MEMS), and complementary metal-oxide-semiconductor (CMOS) based integrated circuit. Furthermore, some typical biochemical methods to optimize the analytical performances of bacterial bioluminescent biosensors/assays are reviewed, followed by a presentation of author's recent work concerning the improved sensitivity of a bioluminescent assay for pesticides. Finally, bacterial bioluminescence as implemented in eukaryotic cells, bioluminescent imaging, and cancer cell therapies is discussed. PMID:25981856

  19. Bathyphotometer bioluminescence potential measurements: A framework for characterizing flow agitators and predicting flow-stimulated bioluminescence intensity

    Latz, Michael I.; Rohr, Jim

    2013-07-01

    Bathyphotometer measurements of bioluminescence are used as a proxy for the abundance of luminescent organisms for studying population dynamics; the interaction of luminescent organisms with physical, chemical, and biological oceanographic processes; and spatial complexity especially in coastal areas. However, the usefulness of bioluminescence measurements has been limited by the inability to compare results from different bathyphotometer designs, or even the same bathyphotometer operating at different volume flow rates. The primary objective of this study was to compare measurements of stimulated bioluminescence of four species of cultured dinoflagellates, the most common source of bioluminescence in coastal waters, using two different bathyphotometer flow agitators as a function of bathyphotometer volume flow rate and dinoflagellate concentration. For both the NOSC and BIOLITE flow agitators and each species of dinoflagellate tested, there was a critical volume flow rate, above which average bioluminescence intensity, designated as bathyphotometer bioluminescence potential (BBP), remained relatively constant and scaled directly with dinoflagellate cell concentration. At supra-critical volume flow rates, the ratio of BIOLITE to NOSC BBP was nearly constant for the same species studied, but varied between species. The spatial pattern and residence time of flash trajectories within the NOSC flow agitator indicated the presence of dominant secondary recirculating flows, where most of the bioluminescence was detected. A secondary objective (appearing in the Appendix) was to study the feasibility of using NOSC BBP to scale flow-stimulated bioluminescence intensity across similar flow fields, where the contributing composition of luminescent species remained the same. Fully developed turbulent pipe flow was chosen because it is hydrodynamically well characterized. Average bioluminescence intensity in a 2.54-cm i.d. pipe was highly correlated with wall shear stress and BBP. This correlation, when further scaled by pipe diameter, effectively predicted bioluminescence intensity in fully developed turbulent flow in a 0.83-cm i.d. pipe. Determining similar correlations between other bathyphotometer flow agitators and flow fields will allow bioluminescence potential measurements to become a more powerful tool for the oceanographic community.

  20. Bioluminescence tomography with Gaussian prior

    Gao, Hao; Zhao, Hongkai; Cong, Wenxiang; Wang, Ge

    2010-01-01

    Parameterizing the bioluminescent source globally in Gaussians provides several advantages over voxel representation in bioluminescence tomography. It is mathematically unique to recover Gaussians [Med. Phys. 31(8), 2289 (2004)] and practically sufficient to approximate various shapes by Gaussians in diffusive medium. The computational burden is significantly reduced since much fewer unknowns are required. Besides, there are physiological evidences that the source can be modeled by Gaussians....

  1. Microtiter plate tests for segregation of bioluminescent bacteria.

    Šimkus, Remigijus; Meškienė, Rita; Ledas, Žilvinas; Baronas, Romas; Meškys, Rolandas

    2016-02-01

    It has been recently shown that bioluminescence imaging can be usefully applied to provide new insights into bacterial self-organization. In this work we employ bioluminescence imaging to record images of nutrient rich liquid cultures of the lux-gene reporter Escherichia coli in microtiter plate wells. The images show that patterns of inhomogenous bioluminescence form along the three-phase contact lines. The paper analyzes the dependencies of the average number of luminous aggregates (clouds) on various environmental factors. In particular, our results show that optimal (neutral) pH and high aeration rates determine the highest mean number of clouds, and that spatiotemporal patterns do not form in the pH buffered suspensions. In addition, a sigmoidal (switch-like) dependence of the number of aggregates on the rate of aeration was observed. The obtained bioluminescence imaging data was interpreted by employing the Keller-Segel-Fisher (KSF) model of chemotaxis and logistic growth, adapted to systems of metabolically flexible (two-state) bacteria. The modified KSF model successfully simulated the observed switch-like responses. The results of the microtiter plate tests and their simulations indicate that the segregation of bacteria with different activities proceeds in the three-phase contact line region. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26039821

  2. The rapid bioluminescence assay method for content of bacteria in dehydrated vegetable and condiment before radiation

    The microbial colony-forming unit (cfu) in dehydrated vegetable and condiment was determined by using ATP bioluminescence method. The result showed that bioluminescence of ATP was correlative to the microbial cfu obviously. The detecting time was within 1-2 h. This method could be applied to determine micro load of products before irradiation sterilization. (authors)

  3. Quantifying the activity of adenoviral E1A CR2 deletion mutants using renilla luciferase bioluminescence and 3'-deoxy-3'-[18F]fluorothymidine positron emission tomography imaging.

    Leyton, Julius; Lockley, Michelle; Aerts, Joeri L; Baird, Sarah K; Aboagye, Eric O; Lemoine, Nicholas R; McNeish, Iain A

    2006-09-15

    The adenoviral E1A CR2 mutant dl922-947 has potent activity in ovarian cancer. We have used Renilla luciferase bioluminescence imaging to monitor viral E1A expression and replication and [18F]fluorothymidine positron emission tomography ([18F]FLT-PET) to quantify the activity of dl922-947 in vivo. We created dlCR2 Ren, with the same E1A CR2 deletion as dl922-947 and the luciferase gene from Renilla reniformis downstream of E1. Light emitted from s.c. and i.p. IGROV1 ovarian carcinoma xenografts was measured following treatment with dlCR2 Ren. Mice bearing s.c. IGROV1 xenografts were injected with 2.96 to 3.7 MBq of [18F]FLT 48 and 168 hours following i.t. injection of dl922-947 or control virus Ad LM-X. The presence of Renilla luciferase in dlCR2 Ren did not reduce in vitro nor in vivo potency compared with dl922-947. Light emission correlated closely with E1A expression in vitro and peaked 48 hours after dlCR2 Ren injection in both s.c. and i.p. IGROV1 xenografts. It diminished by 168 hours in s.c. tumors but persisted for at least 2 weeks in i.p. models. Normalized tumor [18F]FLT uptake at 60 minutes (NUV60), fractional retention, and area under radioactivity curve all decreased marginally 48 hours after dl922-947 treatment and significantly at 168 hours compared with controls. There was a close linear correlation between NUV60 and both tumor proliferation (Ki67 labeling index) and thymidine kinase 1 expression. Renilla luciferase bioluminescence and [18F]FLT-PET imaging are capable of quantifying the activity and effectiveness of E1A CR2-deleted adenoviral mutants in ovarian cancer. PMID:16982761

  4. Bioluminescence tomography based on phantoms with different concentrations of bioluminescent cancer cells

    Li, Senhu; Driessen, Wouter; Sullivan, Sean; Jiang, Huabei

    2006-09-01

    A cubic phantom containing different concentrations of cells in a 5 mm diameter cylindrical hole was tested. Luminescence light emitted from four sides of the phantom was measured and bioluminescence tomography (BLT) was reconstructed with our modified finite element reconstruction algorithm. By adding a weighting factor and threshold in the algorithm, we can detect the targets at any depth in our 3 cm 3 cm phantom for first time.

  5. Random matrix-based dimensionality reduction for bioluminescence tomography reconstruction

    Styles, Iain B.; Basevi, Hector R. A.; Guggenheim, James A.; Dehghani, Hamid

    2013-06-01

    We show how a random matrix can be used to reduce the dimensionality of the bioluminescence tomography reconstruction problem. A randomised low-rank approximation for the sensitivity matrix is computed, and we show how this can be used to reconstruct the bioluminescence source distribution on a randomised basis for the mesh nodes. The distribution on the original mesh can be found easily via a simple matrix multiplication. The majority of the computation required can be performed in advance of the reconstruction, and the reconstruction time itself is of the order milliseconds. This could allow for high frame rate real-time reconstructions to be performed.

  6. In vitro validation of bioluminescent monitoring of disease progression and therapeutic response in leukaemia model animals

    The application of in vivo bioluminescence imaging to non-invasive, quantitative monitoring of tumour models relies on a positive correlation between the intensity of bioluminescence and the tumour burden. We conducted cell culture studies to investigate the relationship between bioluminescent signal intensity and viable cell numbers in murine leukaemia model cells. Interleukin-3 (IL-3)-dependent murine pro-B cell line Ba/F3 was transduced with firefly luciferase to generate cells expressing luciferase stably under the control of a retroviral long terminal repeat. The luciferase-expressing cells were transduced with p190 BCR-ABL to give factor-independent proliferation. The cells were cultured under various conditions, and bioluminescent signal intensity was compared with viable cell numbers and the cell cycle stage. The Ba/F3 cells showed autonomous growth as well as stable luciferase expression following transduction with both luciferase and p190 BCR-ABL, and in vivo bioluminescence imaging permitted external detection of these cells implanted into mice. The bioluminescence intensities tended to reflect cell proliferation and responses to imatinib in cell culture studies. However, the luminescence per viable cell was influenced by the IL-3 concentration in factor-dependent cells and by the stage of proliferation and imatinib concentration in factor-independent cells, thereby impairing the proportionality between viable cell number and bioluminescent signal intensity. Luminescence per cell tended to vary in association with the fraction of proliferating cells. Although in vivo bioluminescence imaging would allow non-invasive monitoring of leukaemia model animals, environmental factors and therapeutic interventions may cause some discrepancies between tumour burden and bioluminescence intensity. (orig.)

  7. In vitro validation of bioluminescent monitoring of disease progression and therapeutic response in leukaemia model animals

    Inoue, Yusuke; Okubo, Toshiyuki [University of Tokyo, Department of Radiology, Institute of Medical Science, Tokyo (Japan); Tojo, Arinobu; Sekine, Rieko; Soda, Yasushi; Kobayashi, Seiichiro; Nomura, Akiko; Izawa, Kiyoko [University of Tokyo, Division of Molecular Therapy, Advanced Clinical Research Centre, Tokyo (Japan); Kitamura, Toshio [University of Tokyo, Division of Cellular Therapy, Advanced Clinical Research Centre, Tokyo (Japan); Ohtomo, Kuni [University of Tokyo, Department of Radiology, Graduate School of Medicine, Tokyo (Japan)

    2006-05-15

    The application of in vivo bioluminescence imaging to non-invasive, quantitative monitoring of tumour models relies on a positive correlation between the intensity of bioluminescence and the tumour burden. We conducted cell culture studies to investigate the relationship between bioluminescent signal intensity and viable cell numbers in murine leukaemia model cells. Interleukin-3 (IL-3)-dependent murine pro-B cell line Ba/F3 was transduced with firefly luciferase to generate cells expressing luciferase stably under the control of a retroviral long terminal repeat. The luciferase-expressing cells were transduced with p190 BCR-ABL to give factor-independent proliferation. The cells were cultured under various conditions, and bioluminescent signal intensity was compared with viable cell numbers and the cell cycle stage. The Ba/F3 cells showed autonomous growth as well as stable luciferase expression following transduction with both luciferase and p190 BCR-ABL, and in vivo bioluminescence imaging permitted external detection of these cells implanted into mice. The bioluminescence intensities tended to reflect cell proliferation and responses to imatinib in cell culture studies. However, the luminescence per viable cell was influenced by the IL-3 concentration in factor-dependent cells and by the stage of proliferation and imatinib concentration in factor-independent cells, thereby impairing the proportionality between viable cell number and bioluminescent signal intensity. Luminescence per cell tended to vary in association with the fraction of proliferating cells. Although in vivo bioluminescence imaging would allow non-invasive monitoring of leukaemia model animals, environmental factors and therapeutic interventions may cause some discrepancies between tumour burden and bioluminescence intensity. (orig.)

  8. Effect of irradiation on bioluminescence spectrum of microbial ATP

    The effect of irradiation on bioluminescence spectrum of dehydrated cabbage microbial ATP was studied. The results showed that the spectral bandwidth of ATP standard was from 490 to 640 nm and the peak wavelength was at 563 nm. The spectral bandwidths of irradiated dehydrated cabbage microbial ATP and CK did not change. Peak wavelengths of dehydrated cabbage irradiated at different dosages were not significantly different from that of CK. The peaks of bioluminescence spectrum of irradiated samples were higher than that of CK, which may be because of the increasing concentration of ATP, and this effect would be kept for quite a long time after irradiation. (authors)

  9. Accounting for filter bandwidth improves the quantitative accuracy of bioluminescence tomography

    Taylor, Shelley L.; Mason, Suzannah K. G.; Glinton, Sophie L.; Cobbold, Mark; Dehghani, Hamid

    2015-09-01

    Bioluminescence imaging is a noninvasive technique whereby surface weighted images of luminescent probes within animals are used to characterize cell count and function. Traditionally, data are collected over the entire emission spectrum of the source using no filters and are used to evaluate cell count/function over the entire spectrum. Alternatively, multispectral data over several wavelengths can be incorporated to perform tomographic reconstruction of source location and intensity. However, bandpass filters used for multispectral data acquisition have a specific bandwidth, which is ignored in the reconstruction. In this work, ignoring the bandwidth is shown to introduce a dependence of the recovered source intensity on the bandwidth of the filters. A method of accounting for the bandwidth of filters used during multispectral data acquisition is presented and its efficacy in increasing the quantitative accuracy of bioluminescence tomography is demonstrated through simulation and experiment. It is demonstrated that while using filters with a large bandwidth can dramatically decrease the data acquisition time, if not accounted for, errors of up to 200% in quantitative accuracy are introduced in two-dimensional planar imaging, even after normalization. For tomographic imaging, the use of this method to account for filter bandwidth dramatically improves the quantitative accuracy.

  10. Novel Bioluminescent Activatable Reporter for Src Tyrosine Kinase Activity in Living Mice

    Leng, Weibing; Li, Dezhi; Chen, Liang; Xia, Hongwei; Tang, Qiulin; Chen, Baoqin; Gong, Qiyong; Gao, Fabao; Bi, Feng

    2016-01-01

    Aberrant activation of the Src kinase is implicated in the development of a variety of human malignancies. However, it is almost impossible to monitor Src activity in an in vivo setting with current biochemical techniques. To facilitate the noninvasive investigation of the activity of Src kinase both in vitro and in vivo, we developed a genetically engineered, activatable bioluminescent reporter using split-luciferase complementation. The bioluminescence of this reporter can be used as a surrogate for Src activity in real time. This hybrid luciferase reporter was constructed by sandwiching a Src-dependent conformationally responsive unit (SH2 domain-Srcpep) between the split luciferase fragments. The complementation bioluminescence of this reporter was dependent on the Src activity status. In our study, Src kinase activity in cultured cells and tumor xenografts was monitored quantitatively and dynamically in response to clinical small-molecular kinase inhibitors, dasatinib and saracatinib. This system was also applied for high-throughput screening of Src inhibitors against a kinase inhibitor library in living cells. These results provide unique insights into drug development and pharmacokinetics/phoarmocodynamics of therapeutic drugs targeting Src signaling pathway enabling the optimization of drug administration schedules for maximum benefit. Using both Firefly and Renilla luciferase imaging, we have successfully monitored Src tyrosine kinase activity and Akt serine/threonine kinase activity concurrently in one tumor xenograft. This dual luciferase reporter imaging system will be helpful in exploring the complex signaling networks in vivo. The strategies reported here can also be extended to study and image other important kinases and the cross-talks among them. PMID:26941850

  11. Novel Bioluminescent Activatable Reporter for Src Tyrosine Kinase Activity in Living Mice.

    Leng, Weibing; Li, Dezhi; Chen, Liang; Xia, Hongwei; Tang, Qiulin; Chen, Baoqin; Gong, Qiyong; Gao, Fabao; Bi, Feng

    2016-01-01

    Aberrant activation of the Src kinase is implicated in the development of a variety of human malignancies. However, it is almost impossible to monitor Src activity in an in vivo setting with current biochemical techniques. To facilitate the noninvasive investigation of the activity of Src kinase both in vitro and in vivo, we developed a genetically engineered, activatable bioluminescent reporter using split-luciferase complementation. The bioluminescence of this reporter can be used as a surrogate for Src activity in real time. This hybrid luciferase reporter was constructed by sandwiching a Src-dependent conformationally responsive unit (SH2 domain-Srcpep) between the split luciferase fragments. The complementation bioluminescence of this reporter was dependent on the Src activity status. In our study, Src kinase activity in cultured cells and tumor xenografts was monitored quantitatively and dynamically in response to clinical small-molecular kinase inhibitors, dasatinib and saracatinib. This system was also applied for high-throughput screening of Src inhibitors against a kinase inhibitor library in living cells. These results provide unique insights into drug development and pharmacokinetics/phoarmocodynamics of therapeutic drugs targeting Src signaling pathway enabling the optimization of drug administration schedules for maximum benefit. Using both Firefly and Renilla luciferase imaging, we have successfully monitored Src tyrosine kinase activity and Akt serine/threonine kinase activity concurrently in one tumor xenograft. This dual luciferase reporter imaging system will be helpful in exploring the complex signaling networks in vivo. The strategies reported here can also be extended to study and image other important kinases and the cross-talks among them. PMID:26941850

  12. A bioluminescent assay for monoamine oxidase activity.

    Valley, Michael P; Zhou, Wenhui; Hawkins, Erika M; Shultz, John; Cali, James J; Worzella, Tracy; Bernad, Laurent; Good, Troy; Good, Dave; Riss, Terry L; Klaubert, Dieter H; Wood, Keith V

    2006-12-15

    This article describes a novel two-step homogeneous bioluminescent assay for monoamine oxidase (MAO) that is simple, sensitive, and amenable to high-throughput screening. In the first step, MAO reacts with an aminopropylether analog of methyl ester luciferin. In the second step, a luciferin detection reagent inactivates MAO and converts the product of the first step into a luminescent signal. The amount of light produced is proportional to the amount of MAO and the time of incubation in the first step, but the luminescent signal is stable in the second step with a half-life greater than 5h. The assay has high precision, is more sensitive than current fluorescent methods, and can accurately measure the binding constants of known substrates and inhibitors. An automated screen of the Sigma-RBI Library of Pharmacologically Active Compounds (LOPAC(1280)) revealed a surprisingly high percentage of MAO inhibitors (16%) with a low false hit rate (0.9%). This implies that a significant number of compounds interact with the MAO enzymes and suggests that it is important to include MAO assays in drug metabolism studies. Other advantages of this bioluminescent assay over comparable fluorescent assays are discussed. PMID:17084801

  13. A Nisin Bioassay Based on Bioluminescence

    Wahlström, G; Saris, P. E. J.

    1999-01-01

    A Lactococcus lactis subsp. lactis strain that can sense the bacteriocin nisin and transduce the signal into bioluminescence was constructed. By using this strain, a bioassay based on bioluminescence was developed for quantification of nisin, for detection of nisin in milk, and for identification of nisin-producing strains. As little as 0.0125 ng of nisin per ml was detected within 3 h by this bioluminescence assay. This detection limit was lower than in previously described methods.

  14. Expanded palette of Nano-lanterns for real-time multicolor luminescence imaging.

    Takai, Akira; Nakano, Masahiro; Saito, Kenta; Haruno, Remi; Watanabe, Tomonobu M; Ohyanagi, Tatsuya; Jin, Takashi; Okada, Yasushi; Nagai, Takeharu

    2015-04-01

    Fluorescence live imaging has become an essential methodology in modern cell biology. However, fluorescence requires excitation light, which can sometimes cause potential problems, such as autofluorescence, phototoxicity, and photobleaching. Furthermore, combined with recent optogenetic tools, the light illumination can trigger their unintended activation. Because luminescence imaging does not require excitation light, it is a good candidate as an alternative imaging modality to circumvent these problems. The application of luminescence imaging, however, has been limited by the two drawbacks of existing luminescent protein probes, such as luciferases: namely, low brightness and poor color variants. Here, we report the development of bright cyan and orange luminescent proteins by extending our previous development of the bright yellowish-green luminescent protein Nano-lantern. The color change and the enhancement of brightness were both achieved by bioluminescence resonance energy transfer (BRET) from enhanced Renilla luciferase to a fluorescent protein. The brightness of these cyan and orange Nano-lanterns was ∼20 times brighter than wild-type Renilla luciferase, which allowed us to perform multicolor live imaging of intracellular submicron structures. The rapid dynamics of endosomes and peroxisomes were visualized at around 1-s temporal resolution, and the slow dynamics of focal adhesions were continuously imaged for longer than a few hours without photobleaching or photodamage. In addition, we extended the application of these multicolor Nano-lanterns to simultaneous monitoring of multiple gene expression or Ca(2+) dynamics in different cellular compartments in a single cell. PMID:25831507

  15. Mathematical Study and Numerical Simulation of Multispectral Bioluminescence Tomography

    Ge Wang; Wenxiang Cong; Weimin Han

    2006-01-01

    Multispectral bioluminescence tomography (BLT) attracts increasingly more attention in the area of optical molecular imaging. In this paper, we analyze the properties of the solutions to the regularized and discretized multispectral BLT problems. First, we show the solution existence, uniqueness, and its continuous dependence on the data. Then, we introduce stable numerical schemes and derive error estimates for numerical solutions. We report some numerical results to illustrate the performan...

  16. Mathematical Study and Numerical Simulation of Multispectral Bioluminescence Tomography

    Cong, Wenxiang

    2006-01-01

    Multispectral bioluminescence tomography (BLT) attracts increasingly more attention in the area of optical molecular imaging. In this paper, we analyze the properties of the solutions to the regularized and discretized multispectral BLT problems. First, we show the solution existence, uniqueness, and its continuous dependence on the data. Then, we introduce stable numerical schemes and derive error estimates for numerical solutions. We report some numerical results to illust...

  17. Preclinical evaluation of destruxin B as a novel Wnt signaling target suppressing proliferation and metastasis of colorectal cancer using non-invasive bioluminescence imaging

    In continuation to our studies toward the identification of direct anti-cancer targets, here we showed that destruxin B (DB) from Metarhizium anisopliae suppressed the proliferation and induced cell cycle arrest in human colorectal cancer (CRC) HT29, SW480 and HCT116 cells. Additionally, DB induced apoptosis in HT29 cells by decreased expression level of anti-apoptotic proteins Bcl-2 and Bcl-xL while increased pro-apoptotic Bax. On the other hand, DB attenuated Wnt-signaling by downregulation of β-catenin, Tcf4 and β-catenin/Tcf4 transcriptional activity, concomitantly with decreased expression of β-catenin target genes cyclin D1, c-myc and survivin. Furthermore, DB affected the migratory and invasive ability of HT29 cells through suppressed MMPs-2 and -9 enzymatic activities. We also found that DB targeted the MAPK and/or PI3K/Akt pathway by reduced expression of Akt, IKK-α, JNK, NF-κB, c-Jun and c-Fos while increased that of IκBα. Finally, we demonstrated that DB inhibited tumorigenesis in HT29 xenograft mice using non-invasive bioluminescence technique. Consistently, tumor samples from DB-treated mice demonstrated suppressed expression of β-catenin, cyclin D1, survivin, and endothelial marker CD31 while increased caspase-3 expression. Collectively, our data supports DB as an inhibitor of Wnt/β-catenin/Tcf signaling pathway that may be beneficial in the CRC management. Highlights: ► Destruxin B (DB) inhibited colorectal cancer cells growth and induced apoptosis. ► MAPK and/or PI3K/Akt cascade cooperates in DB induced apoptosis. ► DB affected the migratory and invasive ability of HT29 cells through MMP-9. ► DB attenuated Wnt-signaling components β-catenin, Tcf4. ► DB attenuated cyclin D1, c-myc, survivin and tumorigenesis in HT29 xenograft mice.

  18. Preclinical evaluation of destruxin B as a novel Wnt signaling target suppressing proliferation and metastasis of colorectal cancer using non-invasive bioluminescence imaging

    Yeh, Chi-Tai [Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China); Center of Excellence for Cancer Research, Taipei Medical University, Taipei, Taiwan (China); Department of Surgery, Taipei Medical University-Shuang Ho Hospital, Taipei, Taiwan (China); Rao, Yerra Koteswara [Institute of Biochemical Sciences and Technology, Chaoyang University of Technology, Taichung, Taiwan (China); Ye, Min [Department of Natural Medicine, School of Pharmaceutical Sciences, Peking University, Beijing (China); Wu, Wen-Shi [Department of Horticulture and Biotechnology, Chinese Culture University, Taipei, Taiwan (China); Chang, Tung-Chen [Department of Surgery, Taipei Medical University-Shuang Ho Hospital, Taipei, Taiwan (China); Wang, Liang-Shun [Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China); Division of Thoracic Surgery, Department of Surgery, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan (China); Wu, Chih-Hsiung [Center of Excellence for Cancer Research, Taipei Medical University, Taipei, Taiwan (China); Department of Surgery, Taipei Medical University-Shuang Ho Hospital, Taipei, Taiwan (China); Wu, Alexander T.H., E-mail: chaw1211@tmu.edu.tw [Ph.D. Program for Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan (China); Department of Radiation Oncology, Taipei Medical University Hospital, Taipei, Taiwan (China); Tzeng, Yew-Min, E-mail: ymtzeng@cyut.edu.tw [Institute of Biochemical Sciences and Technology, Chaoyang University of Technology, Taichung, Taiwan (China)

    2012-05-15

    In continuation to our studies toward the identification of direct anti-cancer targets, here we showed that destruxin B (DB) from Metarhizium anisopliae suppressed the proliferation and induced cell cycle arrest in human colorectal cancer (CRC) HT29, SW480 and HCT116 cells. Additionally, DB induced apoptosis in HT29 cells by decreased expression level of anti-apoptotic proteins Bcl-2 and Bcl-xL while increased pro-apoptotic Bax. On the other hand, DB attenuated Wnt-signaling by downregulation of β-catenin, Tcf4 and β-catenin/Tcf4 transcriptional activity, concomitantly with decreased expression of β-catenin target genes cyclin D1, c-myc and survivin. Furthermore, DB affected the migratory and invasive ability of HT29 cells through suppressed MMPs-2 and -9 enzymatic activities. We also found that DB targeted the MAPK and/or PI3K/Akt pathway by reduced expression of Akt, IKK-α, JNK, NF-κB, c-Jun and c-Fos while increased that of IκBα. Finally, we demonstrated that DB inhibited tumorigenesis in HT29 xenograft mice using non-invasive bioluminescence technique. Consistently, tumor samples from DB-treated mice demonstrated suppressed expression of β-catenin, cyclin D1, survivin, and endothelial marker CD31 while increased caspase-3 expression. Collectively, our data supports DB as an inhibitor of Wnt/β-catenin/Tcf signaling pathway that may be beneficial in the CRC management. Highlights: ► Destruxin B (DB) inhibited colorectal cancer cells growth and induced apoptosis. ► MAPK and/or PI3K/Akt cascade cooperates in DB induced apoptosis. ► DB affected the migratory and invasive ability of HT29 cells through MMP-9. ► DB attenuated Wnt-signaling components β-catenin, Tcf4. ► DB attenuated cyclin D1, c-myc, survivin and tumorigenesis in HT29 xenograft mice.

  19. Spectrally resolved bioluminescence tomography with the third-order simplified spherical harmonics approximation

    Bioluminescence imaging has been extensively applied to in vivo small animal imaging. Quantitative three-dimensional bioluminescent source information obtained by using bioluminescence tomography can directly and much more accurately reflect biological changes as opposed to planar bioluminescence imaging. Preliminary simulated and experimental reconstruction results demonstrate the feasibility and promise of bioluminescence tomography. However, the use of multiple approximations, particularly the diffusion approximation theory, affects the quality of in vivo small animal-based image reconstructions. In the development of new reconstruction algorithms, high-order approximation models of the radiative transfer equation and spectrally resolved data introduce new challenges to the reconstruction algorithm and speed. In this paper, an SP3-based (the third-order simplified spherical harmonics approximation) spectrally resolved reconstruction algorithm is proposed. The simple linear relationship between the unknown source distribution and the spectrally resolved data is established in this algorithm. A parallel version of this algorithm is realized, making BLT reconstruction feasible for the whole body of small animals especially for fine spatial domain discretization. In simulation validations, the proposed algorithm shows improved reconstruction quality compared with diffusion approximation-based methods when high absorption, superficial sources and detection modes are considered. In addition, comparisons between fine and coarse mesh-based BLT reconstructions show the effects of numerical errors in reconstruction image quality. Finally, BLT reconstructions using in vivo mouse experiments further demonstrate the potential and effectiveness of the SP3-based reconstruction algorithm.

  20. Geodesic Regression for Image Time-Series

    NIETHAMMER, MARC; Huang, Yang; Vialard, Franois-Xavier

    2011-01-01

    Registration of image-time series has so far been accomplished (i) by concatenating registrations between image pairs, (ii) by solving a joint estimation problem resulting in piecewise geodesic paths between image pairs, (iii) by kernel based local averaging or (iv) by augmenting the joint estimation with additional temporal irregularity penalties. Here, we propose a generative model extending least squares linear regression to the space of images by using a second-order dynamic formulation f...

  1. REVIEW OF ENVIRONMENTAL APPLICATIONS OF BIOLUMINESCENCE MEASUREMENTS

    This review of the recent literature on environmental applications of bioluminescence systems will focus on in vivo and in vitro bioluminescence methods that have been utilized to elucidate properties of chemicals, toxic and mutagenic effects, and to estimate biomass. he unifying...

  2. Images of time mind, science, reality

    Jaroszkiewicz, George

    2016-01-01

    Have you ever wondered about Time: what it is or how to discuss it? If you have, then you may have been bewildered by the many different views and opinions in many diverse fields to be found, such as physics, mathematics, philosophy, religion, history, and science fiction novels and films. This book will help you unravel fact from fiction. It provides a broad survey of many of these views, these images of time, covering historical, cultural, philosophical, biological, mathematical and physical images of time, including classical and quantum mechanics, special and general relativity and cosmology. This book gives you more than just a review of such images. It provides the reader a basis for judging the scientific soundness of these various images. It develops the reader's critical ability to distinguish Images of Time in terms of its contextual completeness. Differentiating between metaphysical images (which cannot be scientifically validated) and those that could, in principle, be put to empirical test. Showi...

  3. The subcellular origin of bioluminescence in Noctiluca miliaris.

    Eckert, R; Reynolds, G T

    1967-05-01

    The light emitted by Noctiluca has its origin in 1 to 5 x 10(4) organelles ("microsources") which are scattered throughout the perivacuolar cytoplasm, and which appear to be the elementary functional units of bioluminescence. Microscopical techniques, image intensification, and microphotometry were employed in their investigation. Microsources are fluorescent, strongly phase-retarding, and range widely in diameter below 1.5 microns. The number of quanta emitted in a flash from a microsource ("microflash") is of the order of 10(5) photons. However, microflashes show a wide range of intensities, which are correlated with the size of the organelles from which they arise. Each organelle responds repetitively and with reproducible time course to a succession of invading triggering potentials. Reversible changes in the intensity of the flash emitted by the whole cell ("macroflash") occur because of graduations in intensity of microflashes rather than as a result of changes in the number of responsive organelles. The shape of the flash emitted by individual microsources resembles that of the macroflash except for slightly shorter rise and decay times. It is concluded that the macroflash results from somewhat asynchronous, but otherwise parallel summation of microflashes. PMID:5340466

  4. Bacterial bioluminescence and Gumbel statistics: From quorum sensing to correlation

    Delle Side, Domenico; Velardi, Luciano; Nassisi, Vincenzo; Pennetta, Cecilia; Alifano, Pietro; Talà, Adelfia; Salvatore Tredici, Maurizio

    2013-12-01

    We show that, in particular experimental conditions, the time course of the radiant fluxes, measured from a bioluminescent emission of a Vibrio harveyi related strain, collapse after suitable rescaling onto the Gumbel distribution of extreme value theory. We argue that the activation times of the strain luminous emission follow the universal behavior described by this statistical law, in spite of the fact that no extremal process is known to occur.

  5. Understanding bioluminescence in dinoflagellates - how far have we come?

    Martha Valiadi; Debora Iglesias-Rodriguez

    2013-01-01

    Some dinoflagellates possess the remarkable genetic, biochemical, and cellular machinery to produce bioluminescence. Bioluminescent species appear to be ubiquitous in surface waters globally and include numerous cosmopolitan and harmful taxa. Nevertheless, bioluminescence remains an enigmatic topic in biology, particularly with regard to the organisms’ lifestyle. In this paper, we review the literature on the cellular mechanisms, molecular evolution, diversity, and ecology of bioluminescence ...

  6. Bioluminescence tomography based on the phase approximation model

    Cong, W.; Wang, G

    2010-01-01

    A reconstruction method of bioluminescence sources is proposed based on a phase approximation model. Compared with the diffuse approximation, this phase approximation model more correctly predicts bioluminescence photon propagation in biological tissues, so that bioluminescence tomography can accurately locate and quantify the distribution of bioluminescence sources. The compressive sensing (CS) technique is applied to regularize the inverse source reconstruction to enhance numerical stabilit...

  7. Methodological problems of direct bioluminescent ATP assay in platelets and erythrocytes.

    Girotti, S; Ferri, E; Cascione, M L; Comuzio, S; Mazzuca, A; Orlandini, A; Breccia, A

    1989-07-01

    Direct bioluminescent ATP determination in platelets and erythrocytes involves the study of different parameters which are discussed here. Some parameters are linked to the bioluminescent reaction and to the analyte (ATP); others have regard to the biological matrix. The composition of bioluminescent reagents and the preparation and conservation of the ATP standard, also in the presence of excipients, are among the first given. Matrix problems involve cell characteristics related to age and form, lysis resistance and the possible formation of aggregates (platelets) that may inhibit the complete release of ATP. For these reasons we used the most efficient ATP release agent with the lowest inhibitory effect on luciferase. The data obtained correlate well with a bioluminescent method requiring extraction with ethanol/EDTA, and therefore more time, for ATP determination in platelets and erythrocytes. PMID:2801244

  8. Determination of the Genetic Diversity of Different Bioluminescent Bacteria by Pulsed-Field Gel Electrophoresis (PFGE

    Ersoy Omeroglu

    2015-07-01

    Full Text Available Background There are 4 different genera (i.e. Vibrio, Aliivibrio, Photobacterium, and Shewanella in the new classification of bioluminescent bacteria. The mechanism of bioluminescence has yet to be fully elucidated. Therefore, the determination of physiological and genetic characteristics of bioluminescent bacteria isolated from different sources is very important. Pulsed-Field Gel Electrophoresis (PFGE has the highest discriminatory power among the different molecular typing methods for the investigation of the clonal relationships between bacteria. For the PFGE analysis of bioluminescent bacteria, the NotI-HF is the method of choice among the restriction enzymes. Objectives The present study aimed to determine genetic relatedness via PFGE in 41 bioluminescent bacteria (belonging to 10 different species isolated and identified from various marine sources. Materials and Methods Different bioluminescent bacteria (i.e. Vibrio gigantis, V. azureus, V. harveyi, V. lentus, V. crassostreae, V. orientalis, Aliivibrio logei, A. fischeri, Shewanella woodyi, and Photobacterium kishitanii were analyzed by PFGE using the NotI-HF restriction enzyme. The whole DNA of the strains embedded into the agarose plugs was digested with enzyme at 37C for 30 minutes. CHEF-Mapper PFGE system was used for electrophoresis and band profile of the strains for the NotI-HF restriction enzyme were analyzed by Bio-Profil-1D++ software (Vilber Lourmat at 10% homology coefficient. Results Although all experiments were performed three times, four of forty-one bioluminescent strains (V. gigantis E-16, H-16 and S3W46 strains and A. fischeri E-4 strain could not be typed by PFGE technique with NotI-HF enzyme. While only two strains (V. crassostreae H-12 and H-19 strains were exhibiting same band pattern profiles (100% genome homology, thirty-six different PFGE band patterns were obtained. Pattern homologies changed between 66% - 92%, 73% - 83% and 49% - 100% for V. gigantis, V. harveyi and other strains, respectively. Conclusions The obtained results revealed that there has been a high rate of genetic diversity in bioluminescent strains isolated from Gulf of Izmir and V. lentus and V. crassostreae strains could be also bioluminescent for the first report. At the same time, PFGE analysis of bioluminescent bacteria including four different genera and ten different species were shown for the first time by this study. It is considered that data acquired by this study will contribute evolution and mechanism of bioluminescence to further works to be done.

  9. Bioluminescent human breast cancer cell lines that permit rapid and sensitive in vivo detection of mammary tumors and multiple metastases in immune deficient mice

    Our goal was to generate xenograft mouse models of human breast cancer based on luciferase-expressing MDA-MB-231 tumor cells that would provide rapid mammary tumor growth; produce metastasis to clinically relevant tissues such as lymph nodes, lung, and bone; and permit sensitive in vivo detection of both primary and secondary tumor sites by bioluminescent imaging. Two clonal cell sublines of human MDA-MB-231 cells that stably expressed firefly luciferase were isolated following transfection of the parental cells with luciferase cDNA. Each subline was passaged once or twice in vivo to enhance primary tumor growth and to increase metastasis. The resulting luciferase-expressing D3H1 and D3H2LN cells were analyzed for long-term bioluminescent stability, primary tumor growth, and distal metastasis to lymph nodes, lungs, bone and soft tissues by bioluminescent imaging. Cells were injected into the mammary fat pad of nude and nude-beige mice or were delivered systemically via intracardiac injection. Metastasis was also evaluated by ex vivo imaging and histologic analysis postmortem. The D3H1 and D3H2LN cell lines exhibited long-term stable luciferase expression for up to 4–6 months of accumulative tumor growth time in vivo. Bioluminescent imaging quantified primary mammary fat pad tumor development and detected early spontaneous lymph node metastasis in vivo. Increased frequency of spontaneous lymph node metastasis was observed with D3H2LN tumors as compared with D3H1 tumors. With postmortem ex vivo imaging, we detected additional lung micrometastasis in mice with D3H2LN mammary tumors. Subsequent histologic evaluation of tissue sections from lymph nodes and lung lobes confirmed spontaneous tumor metastasis at these sites. Following intracardiac injection of the MDA-MB-231-luc tumor cells, early metastasis to skeletal tissues, lymph nodes, brain and various visceral organs was detected. Weekly in vivo imaging data permitted longitudinal analysis of metastasis at multiple sites simultaneously. Ex vivo imaging data from sampled tissues verified both skeletal and multiple soft tissue tumor metastasis. This study characterized two new bioluminescent MDA-MB-231-luc human breast carcinoma cell lines with enhanced tumor growth and widespread metastasis in mice. Their application to current xenograft models of breast cancer offers rapid and highly sensitive detection options for preclinical assessment of anticancer therapies in vivo

  10. Increased bioassay sensitivity of bioactive molecule discovery using metal-enhanced bioluminescence

    Golberg, Karina, E-mail: karingo@bgu.ac.il; Elbaz, Amit [Ben-Gurion University of the Negev, Avram and Stella Goldstein-Goren Department of Biotechnology Engineering (Israel); McNeil, Ronald [The Institute of Fluorescence, University of Maryland Baltimore County (United States); Kushmaro, Ariel [Ben-Gurion University of the Negev, Avram and Stella Goldstein-Goren Department of Biotechnology Engineering (Israel); Geddes, Chris D. [The Institute of Fluorescence, University of Maryland Baltimore County (United States); Marks, Robert S., E-mail: rsmarks@bgu.ac.il [Ben-Gurion University of the Negev, Avram and Stella Goldstein-Goren Department of Biotechnology Engineering (Israel)

    2014-12-15

    We report the use of bioluminescence signal enhancement via proximity to deposited silver nanoparticles for bioactive compound discovery. This approach employs a whole-cell bioreporter harboring a plasmid-borne fusion of a specific promoter incorporated with a bioluminescence reporter gene. The silver deposition process was first optimized to provide optimal nanoparticle size in the reaction time dependence with fluorescein. The use of silver deposition of 350 nm particles enabled the doubling of the bioluminescent signal amplitude by the bacterial bioreporter when compared to an untouched non-silver-deposited microtiter plate surface. This recording is carried out in the less optimal but necessary far-field distance. SEM micrographs provided a visualization of the proximity of the bioreporter to the silver nanoparticles. The electromagnetic field distributions around the nanoparticles were simulated using Finite Difference Time Domain, further suggesting a re-excitation of non-chemically excited bioluminescence in addition to metal-enhanced bioluminescence. The possibility of an antiseptic silver effect caused by such a close proximity was eliminated disregarded by the dynamic growth curves of the bioreporter strains as seen using viability staining. As a highly attractive biotechnology tool, this silver deposition technique, coupled with whole-cell sensing, enables increased bioluminescence sensitivity, making it especially useful for cases in which reporter luminescence signals are very weak.

  11. Increased bioassay sensitivity of bioactive molecule discovery using metal-enhanced bioluminescence

    We report the use of bioluminescence signal enhancement via proximity to deposited silver nanoparticles for bioactive compound discovery. This approach employs a whole-cell bioreporter harboring a plasmid-borne fusion of a specific promoter incorporated with a bioluminescence reporter gene. The silver deposition process was first optimized to provide optimal nanoparticle size in the reaction time dependence with fluorescein. The use of silver deposition of 350 nm particles enabled the doubling of the bioluminescent signal amplitude by the bacterial bioreporter when compared to an untouched non-silver-deposited microtiter plate surface. This recording is carried out in the less optimal but necessary far-field distance. SEM micrographs provided a visualization of the proximity of the bioreporter to the silver nanoparticles. The electromagnetic field distributions around the nanoparticles were simulated using Finite Difference Time Domain, further suggesting a re-excitation of non-chemically excited bioluminescence in addition to metal-enhanced bioluminescence. The possibility of an antiseptic silver effect caused by such a close proximity was eliminated disregarded by the dynamic growth curves of the bioreporter strains as seen using viability staining. As a highly attractive biotechnology tool, this silver deposition technique, coupled with whole-cell sensing, enables increased bioluminescence sensitivity, making it especially useful for cases in which reporter luminescence signals are very weak

  12. NanoLuc: A Small Luciferase Is Brightening Up the Field of Bioluminescence.

    England, Christopher G; Ehlerding, Emily B; Cai, Weibo

    2016-05-18

    The biomedical field has greatly benefited from the discovery of bioluminescent proteins. Currently, scientists employ bioluminescent systems for numerous biomedical applications, ranging from highly sensitive cellular assays to bioluminescence-based molecular imaging. Traditionally, these systems are based on Firefly and Renilla luciferases; however, the applicability of these enzymes is limited by their size, stability, and luminescence efficiency. NanoLuc (NLuc), a novel bioluminescence platform, offers several advantages over established systems, including enhanced stability, smaller size, and >150-fold increase in luminescence. In addition, the substrate for NLuc displays enhanced stability and lower background activity, opening up new possibilities in the field of bioluminescence imaging. The NLuc system is incredibly versatile and may be utilized for a wide array of applications. The increased sensitivity, high stability, and small size of the NLuc system have the potential to drastically change the field of reporter assays in the future. However, as with all such technology, NLuc has limitations (including a nonideal emission for in vivo applications and its unique substrate) which may cause it to find restricted use in certain areas of molecular biology. As this unique technology continues to broaden, NLuc may have a significant impact in both preclinical and clinical fields, with potential roles in disease detection, molecular imaging, and therapeutic monitoring. This review will present the NLuc technology to the scientific community in a nonbiased manner, allowing the audience to adopt their own views of this novel system. PMID:27045664

  13. Experimental Study on Bioluminescence Tomography with Multimodality Fusion

    Yujie Lv

    2007-09-01

    Full Text Available To verify the influence of a priori information on the nonuniqueness problem of bioluminescence tomography (BLT, the multimodality imaging fusion based BLT experiment is performed by multiview noncontact detection mode, which incorporates the anatomical information obtained by the microCT scanner and the background optical properties based on diffuse reflectance measurements. In the reconstruction procedure, the utilization of adaptive finite element methods (FEMs and a priori permissible source region refines the reconstructed results and improves numerical robustness and efficiency. The comparison between the absence and employment of a priori information shows that multimodality imaging fusion is essential to quantitative BLT reconstruction.

  14. Time Variant Change Analysis in Satellite Images

    Rachita Sharma; Sanjay Kumar Dubey

    2013-01-01

    This paper describes the time variant changes in satellite images using Self Organizing Feature Map (SOFM) technique associated with Artificial Neural Network. In this paper, we take a satellite image and find the time variant changes using above technique with the help of MATLAB. This paper reviews remotely sensed data analysis with neural networks. First, we present an overview of the main concepts underlying Artificial Neural Networks (ANNs), including the main architectures and learning a...

  15. Image Fusion for Travel Time Tomography Inversion

    Liu Linan

    2015-09-01

    Full Text Available The travel time tomography technology had achieved wide application, the hinge of tomography was inversion algorithm, the ray path tracing technology had a great impact on the inversion results. In order to improve the SNR of inversion image, comprehensive utilization of inversion results with different ray tracing can be used. We presented an imaging fusion method based on improved Wilkinson iteration method. Firstly, the shortest path method and the linear travel time interpolation were used for forward calculation; then combined the improved Wilkinson iteration method with super relaxation precondition method to reduce the condition number of matrix and accelerate iterative speed, the precise integration method was used to solve the inverse matrix more precisely in tomography inversion process; finally, use wavelet transform for image fusion, obtain the final image. Therefore, the ill-conditioned linear equations were changed into iterative normal system through two times of treatment and using images with different forward algorithms for image fusion, it reduced the influence effect of measurement error on imaging. Simulation results showed that, this method can eliminate the artifacts in images effectively, it had extensive practical significance.

  16. Reverse-Time Migration Based Optical Imaging.

    Wang, Zhiyong; Ding, Hao; Lu, Guijin; Bi, Xiaohong

    2016-01-01

    We theoretically demonstrated a new optical imaging technique based on reverse-time migration (RTM) for reconstructing optical structures in homogeneous media for the first time. RTM is a powerful wave-equation-based method to reconstruct the image of the structure by modeling the wave propagation inside the media with both forward modeling and reverse-time extrapolation. While RTM is commonly used with acoustic seismic waves, this paper represents the first effort to develop optical RTM imaging method for biomedical research. To refine the image quality, we further developed new methods to suppress the low-wavenumber artifact (LWA). When compared with the conventional means for LWA suppression such as Laplacian filtering, illumination normalization, and the ratio method, our new derivative-based and power-image methods are able to significantly reduce LWA, resulting in high-quality reconstructed images with sufficient contrasts and spatial resolutions for structure identification. The optical RTM imaging technique may provide a new platform for non-invasive optical imaging of structures in deep layers of tissues for biomedical applications. PMID:26292337

  17. Analytical Applications of Bioluminescence and Chemiluminescence

    Chappelle, E. W. (Editor); Picciolo, G. L. (Editor)

    1975-01-01

    Bioluminescence and chemiluminescence studies were used to measure the amount of adenosine triphosphate and therefore the amount of energy available. Firefly luciferase - luciferin enzyme system was emphasized. Photometer designs are also considered.

  18. Coherent interferometric imaging, time gating and beamforming

    Coherent interferometric imaging is based on the backpropagation of local spacetime cross-correlations of array data and was introduced in order to improve images when the medium between the array and the object to be imaged is inhomogeneous and unknown (Borcea et al 2005 Inverse Problems 21 1419). Although this method has been shown to be effective and is well founded theoretically, the coherent interferometric imaging function is computationally expensive and therefore difficult to use. In this paper, we show that this function is equivalent to a windowed beamformer energy function, that is, a quadratic function that involves only time gating and time delaying signals in emission and in reception. In this form the coherent interferometric imaging can be implemented efficiently both in hardware and software, that is, at a computational cost that is comparable to the usual beamforming and migration imaging methods. We also revisit the trade-off between enhanced image stability and loss of resolution in coherent interferometry from the point of view of its equivalence to a windowed beamformer energy imaging function

  19. Circadian Control Sheds Light on Fungal Bioluminescence

    Oliveira, Anderson G.; Cassius V. Stevani; Waldenmaier, Hans E.; Viviani, Vadim; Emerson, Jillian M.; Loros, Jennifer J.; Dunlap, Jay C.

    2015-01-01

    Bioluminescence, the creation and emission of light by organisms, affords insight into the lives of organisms doing it. Luminous living things are widespread and access diverse mechanisms to generate and control luminescence [1-5]. Among the least studied bioluminescent organisms are phylogenetically rare fungi – only 71 species, all within the ~9000 fungi of the temperate and tropical Agaricales Order - are reported from among ~100,000 described fungal species [6,7]. All require oxygen [8] a...

  20. Bioluminescence profile in the deep Pacific Ocean

    Bradner, H.; Bartlett, M.; Blackinton, G.; Clem, J.; Karl, D.; Learned, J.; Lewitus, A.; Matsuno, S.; O'Connor, D.; Peatman, W.; Reichle, M.; Roos, C.; Waters, J.; Webster, M.; Yarbrough, M.

    1987-11-01

    The vertical profile of bioluminescence at a station hear Hawaii has been measured to a depth of 4300 m using a calibrated instrument with a threshold sensitivity of 400 photons cm -2 s -1. The measured light is dominated by flashes over a very faint ambient background. The median light levels follow an exponential scaling law below 2000 m and decrease at the rate of 1/e per kilometer. Stimulated bioluminescence is observed in the wake of the instrument, even at depth.

  1. Gemcitabine upregulates ABCG2/BCRP and modulates the intracellular pharmacokinetic profiles of bioluminescence in pancreatic cancer cells.

    Sun, Yue; Gu, Mancang; Zhu, Lixin; Liu, Junying; Xiong, Yang; Wei, Yinghui; Li, Fanzhu

    2016-03-01

    A lack of methods capable of exploring real-time intracellular drug deposition has since limited the investigation of gemcitabine-induced multidrug resistance in vitro and in vivo. Specifically, resistance induced by D-luciferin, a substrate of the breast cancer resistance protein (ABCG2/BCRP), has recently attracted clinical attention, but further investigation has been limited. Herein, the intracellular pharmacokinetic behavior of D-luciferin was investigated in pancreatic cancer cell lines in real time by using bioluminescence imaging. To achieve this feat, BxPC3 and Panc1 pancreatic cancer cells overexpressing firefly luciferase were treated with gemcitabine in a dose and time gradient manner in vitro. The intracellular pharmacokinetic profiles of each group were then determined through the acquisition of bioluminescent signal intensity of D-luciferin in cells. Simultaneously, key pharmacokinetic parameters including area under the curve, elimination rate constant (K), and mean resident time were calculated according to the noncompartment model. ABCG2 protein levels following gemcitabine treatment were detected through western blot, and gemcitabine showed no significant effect on luciferase activity over dimethyl sulfoxide (DMSO) as a control (P>0.05). However, gemcitabine significantly increased K values while suppressing area under the curve and mean resident time compared with DMSO (Pbioluminescent model and its capability to observe the onset of chemoresistance in real time. PMID:26556627

  2. Three-dimensional multi bioluminescent sources reconstruction based on adaptive finite element method

    Ma, Xibo; Tian, Jie; Zhang, Bo; Zhang, Xing; Xue, Zhenwen; Dong, Di; Han, Dong

    2011-03-01

    Among many optical molecular imaging modalities, bioluminescence imaging (BLI) has more and more wide application in tumor detection and evaluation of pharmacodynamics, toxicity, pharmacokinetics because of its noninvasive molecular and cellular level detection ability, high sensitivity and low cost in comparison with other imaging technologies. However, BLI can not present the accurate location and intensity of the inner bioluminescence sources such as in the bone, liver or lung etc. Bioluminescent tomography (BLT) shows its advantage in determining the bioluminescence source distribution inside a small animal or phantom. Considering the deficiency of two-dimensional imaging modality, we developed three-dimensional tomography to reconstruct the information of the bioluminescence source distribution in transgenic mOC-Luc mice bone with the boundary measured data. In this paper, to study the osteocalcin (OC) accumulation in transgenic mOC-Luc mice bone, a BLT reconstruction method based on multilevel adaptive finite element (FEM) algorithm was used for localizing and quantifying multi bioluminescence sources. Optical and anatomical information of the tissues are incorporated as a priori knowledge in this method, which can reduce the ill-posedness of BLT. The data was acquired by the dual modality BLT and Micro CT prototype system that was developed by us. Through temperature control and absolute intensity calibration, a relative accurate intensity can be calculated. The location of the OC accumulation was reconstructed, which was coherent with the principle of bone differentiation. This result also was testified by ex vivo experiment in the black 96-plate well using the BLI system and the chemiluminescence apparatus.

  3. Can compression reduce forensic image time?

    Brian Cusack

    Full Text Available Creating a forensic copy (image of a hard disk drive is one of the fundamental tasks a computer forensic analyst must perform. Time is often critical, and there is a need to consider a trade-off between a number of factors to achieve best results. This paper reports the results from an exploratory study into the impact of using disk drive compression on the time needed to image (and verify a hard disk drive. It was found that time reduction may be achieved once the trade-off of contributing variables was properly estimated. The findings led the investigators to suggest a step-by-step decision making process for analysts when considering disk compression as a means for reducing total image processing time.

  4. Doubling time of liver metastase images

    For our study, where clinical and scintigraphic observation seldom lasts more than two years and where measurable metastases always exceed 1 cm3, the exponential model was adopted and our results were all calculated with GERSTENBERG's formula which gives an apparent doubling time. The liver metastases were measured on the scintigraphic image obtained, a more or less sharply limited blank which makes for a first difficulty of judgement. Two magnascanner V type PICKER 5-inch crystal scintigraphs were used, giving three images simultaneously by a transcriber made up of a stylus and a light spot built into the detection system. The isotope used is colloidal gold (198Au) phagocytized by the Kuepfferian reticulo-endothelial system. The doubling time for liver metastase scintigraphic images calculated for fifteen patients having undergone one or more isotopic checks after a first metastase image was discovered range from 10 to 103 days

  5. Real-time neutron radiography imaging system

    Dias, Ailton F.; de Albuquerque Araujo, Arnaldo

    1994-05-01

    This paper describes preliminary work on a real-time neutron radiography imaging system. Initially, the system provided neutron radiographs on photographic film using a gadolinium foil converter. The photos were digitized by a flat scanner. The system implements digital image processing functions for: counting and sizing, measurement, analysis, enhancement, geometric operations and scripting. After the development of these functions, experiments were done on the real-time imaging system and the functions were applied on images captured by a CCD camera. This is pioneer work related to neutron radiography in Brazil. This project is particularly original because our nuclear reactor has unique features: its core lies in a 6 m pool and the neutrons must be driven to the surface by a pipe. Another challenge of this project is the elimination of any light intensifier between the converter screen and the CCD camera. Neutron converter deficiencies have been compensated by applying digital image techniques to the neutron images. A low cost system has been achieved by exploring the benefits of digital image processing. Initial results provided by this system have encouraged us to continue the research and to enlarge its capability.

  6. An adaptive regularization parameter choice strategy for multispectral bioluminescence tomography

    Feng Jinchao; Qin Chenghu; Jia Kebin; Han Dong; Liu Kai; Zhu Shouping; Yang Xin; Tian Jie [Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, P. O. Box 2728, Beijing 100190 (China); College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing 100124 (China); Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, P. O. Box 2728, Beijing 100190 (China); Medical Image Processing Group, Institute of Automation, Chinese Academy of Sciences, P. O. Box 2728, Beijing 100190 (China) and School of Life Sciences and Technology, Xidian University, Xi' an 710071 (China)

    2011-11-15

    Purpose: Bioluminescence tomography (BLT) provides an effective tool for monitoring physiological and pathological activities in vivo. However, the measured data in bioluminescence imaging are corrupted by noise. Therefore, regularization methods are commonly used to find a regularized solution. Nevertheless, for the quality of the reconstructed bioluminescent source obtained by regularization methods, the choice of the regularization parameters is crucial. To date, the selection of regularization parameters remains challenging. With regards to the above problems, the authors proposed a BLT reconstruction algorithm with an adaptive parameter choice rule. Methods: The proposed reconstruction algorithm uses a diffusion equation for modeling the bioluminescent photon transport. The diffusion equation is solved with a finite element method. Computed tomography (CT) images provide anatomical information regarding the geometry of the small animal and its internal organs. To reduce the ill-posedness of BLT, spectral information and the optimal permissible source region are employed. Then, the relationship between the unknown source distribution and multiview and multispectral boundary measurements is established based on the finite element method and the optimal permissible source region. Since the measured data are noisy, the BLT reconstruction is formulated as l{sub 2} data fidelity and a general regularization term. When choosing the regularization parameters for BLT, an efficient model function approach is proposed, which does not require knowledge of the noise level. This approach only requests the computation of the residual and regularized solution norm. With this knowledge, we construct the model function to approximate the objective function, and the regularization parameter is updated iteratively. Results: First, the micro-CT based mouse phantom was used for simulation verification. Simulation experiments were used to illustrate why multispectral data were used rather than monochromatic data. Furthermore, the study conducted using an adaptive regularization parameter demonstrated our ability to accurately localize the bioluminescent source. With the adaptively estimated regularization parameter, the reconstructed center position of the source was (20.37, 31.05, 12.95) mm, and the distance to the real source was 0.63 mm. The results of the dual-source experiments further showed that our algorithm could localize the bioluminescent sources accurately. The authors then presented experimental evidence that the proposed algorithm exhibited its calculated efficiency over the heuristic method. The effectiveness of the new algorithm was also confirmed by comparing it with the L-curve method. Furthermore, various initial speculations regarding the regularization parameter were used to illustrate the convergence of our algorithm. Finally, in vivo mouse experiment further illustrates the effectiveness of the proposed algorithm. Conclusions: Utilizing numerical, physical phantom and in vivo examples, we demonstrated that the bioluminescent sources could be reconstructed accurately with automatic regularization parameters. The proposed algorithm exhibited superior performance than both the heuristic regularization parameter choice method and L-curve method based on the computational speed and localization error.

  7. An adaptive regularization parameter choice strategy for multispectral bioluminescence tomography

    Purpose: Bioluminescence tomography (BLT) provides an effective tool for monitoring physiological and pathological activities in vivo. However, the measured data in bioluminescence imaging are corrupted by noise. Therefore, regularization methods are commonly used to find a regularized solution. Nevertheless, for the quality of the reconstructed bioluminescent source obtained by regularization methods, the choice of the regularization parameters is crucial. To date, the selection of regularization parameters remains challenging. With regards to the above problems, the authors proposed a BLT reconstruction algorithm with an adaptive parameter choice rule. Methods: The proposed reconstruction algorithm uses a diffusion equation for modeling the bioluminescent photon transport. The diffusion equation is solved with a finite element method. Computed tomography (CT) images provide anatomical information regarding the geometry of the small animal and its internal organs. To reduce the ill-posedness of BLT, spectral information and the optimal permissible source region are employed. Then, the relationship between the unknown source distribution and multiview and multispectral boundary measurements is established based on the finite element method and the optimal permissible source region. Since the measured data are noisy, the BLT reconstruction is formulated as l2 data fidelity and a general regularization term. When choosing the regularization parameters for BLT, an efficient model function approach is proposed, which does not require knowledge of the noise level. This approach only requests the computation of the residual and regularized solution norm. With this knowledge, we construct the model function to approximate the objective function, and the regularization parameter is updated iteratively. Results: First, the micro-CT based mouse phantom was used for simulation verification. Simulation experiments were used to illustrate why multispectral data were used rather than monochromatic data. Furthermore, the study conducted using an adaptive regularization parameter demonstrated our ability to accurately localize the bioluminescent source. With the adaptively estimated regularization parameter, the reconstructed center position of the source was (20.37, 31.05, 12.95) mm, and the distance to the real source was 0.63 mm. The results of the dual-source experiments further showed that our algorithm could localize the bioluminescent sources accurately. The authors then presented experimental evidence that the proposed algorithm exhibited its calculated efficiency over the heuristic method. The effectiveness of the new algorithm was also confirmed by comparing it with the L-curve method. Furthermore, various initial speculations regarding the regularization parameter were used to illustrate the convergence of our algorithm. Finally, in vivo mouse experiment further illustrates the effectiveness of the proposed algorithm. Conclusions: Utilizing numerical, physical phantom and in vivo examples, we demonstrated that the bioluminescent sources could be reconstructed accurately with automatic regularization parameters. The proposed algorithm exhibited superior performance than both the heuristic regularization parameter choice method and L-curve method based on the computational speed and localization error.

  8. Real-time inspection by submarine images

    Tascini, Guido; Zingaretti, Primo; Conte, Giuseppe

    1996-10-01

    A real-time application of computer vision concerning tracking and inspection of a submarine pipeline is described. The objective is to develop automatic procedures for supporting human operators in the real-time analysis of images acquired by means of cameras mounted on underwater remotely operated vehicles (ROV) Implementation of such procedures gives rise to a human-machine system for underwater pipeline inspection that can automatically detect and signal the presence of the pipe, of its structural or accessory elements, and of dangerous or alien objects in its neighborhood. The possibility of modifying the image acquisition rate in the simulations performed on video- recorded images is used to prove that the system performs all necessary processing with an acceptable robustness working in real-time up to a speed of about 2.5 kn, widely greater than that the actual ROVs and the security features allow.

  9. Real-time imaging detectors for portal imaging

    This paper reviews the status of real-time imaging systems which are used in radiation-therapy for radiotherapy localization and verification. Imaging systems under review include (1) metal-fluorescent screens, optically coupled to video cameras, (2) metal-phosphor screen in direct contact with two-dimensional photo-diode array (flat panel detector), (3) two-dimensional liquid ionization chamber and (5) linear diode arrays. These systems permit frequent verification during the treatment and have been shown to be very useful. Unfortunately the image quality achieved, while impressive considering the short time the devices have been on the market, is significantly inferior to that which is available form the metal/film combination (port film). The spatial resolution is about 1 lp/mm at 10% MTF, the Detective Quantum Efficiency (DQE) is less than 1% at 0 lp/mm and less than 0.1% at 1 lp/mm. It is also noted that these systems have not reached their ultimate limits of performance yet. The levels of x-ray fluence in the radiotherapy beam should allow a significant increase in the image quality. Nevertheless, the digital imaging systems available now are superior to analog film based systems because they provide a separation between the important functions of detection and display. They can provide almost instant image processing to optimize the information to be presented to the human observer. 100 refs., 11 figs., 4 tabs

  10. Actual imaging time in fetal MRI

    Objective: Safety issues in magnetic resonance imaging (MRI) are important, especially in fetal MRI. However, since basic data with respect of the effective exposure time in fetal MRI are not available, this study aimed to determine the actual imaging time during a fetal MRI study. Methods: 100 fetal MRI studies of singleton pregnancies performed on a 1.5 T system were analysed with respect to study duration (from starting the survey scan until the end of study), the number of sequences acquired, and the actual imaging time, which was calculated by adding up scan time of each sequence. Furthermore, each sequence type was analysed regarding the number of acquisitions, specific absorption rates (SAR), and duration. Results: Mean study duration was 34.6 min (range: 1458 min; standard deviation (SD): 9.7 min), the average number of sequences acquired was 26.6 (range: 1144, SD: 6.6). Actual scan time averaged 11.4 min (range: 419 min, SD: 4.0 min). Ultrafast T2-weighted and steady-state free-precession sequences accounted for 62.3% of actual scan time, and were distributed over the whole duration of the study. Conclusion: Actual imaging time only accounts for 33% of total study time and is not continuous. The remaining time is consumed by the preparation phases of the scanner, and is spent with planning sequences and the eventual repositioning of the coil and/or pregnant woman. These data may help to more accurately estimate the exposure to radiofrequency deposition and noise during fetal MRI studies.

  11. Skill Analysis with Time Series Image Data

    Maeda, Toshiyuki; Fujii, Masanori; Hayashi, Isao

    2014-01-01

    We present a skill analysis with time series image data using data mining methods, focused on table tennis. We do not use body model, but use only hi-speed movies, from which time series data are obtained and analyzed using data mining methods such as C4.5 and so on. We identify internal models for technical skills as evaluation skillfulness for the forehand stroke of table tennis, and discuss mono and meta-functional skills for improving skills.

  12. A Monte-Carlo-Based Network Method for Source Positioning in Bioluminescence Tomography

    Zhun Xu; Xiaolei Song; Xiaomeng Zhang; Jing Bai

    2007-01-01

    We present an approach based on the improved Levenberg Marquardt (LM) algorithm of backpropagation (BP) neural network to estimate the light source position in bioluminescent imaging. For solving the forward problem, the table-based random sampling algorithm (TBRS), a fast Monte Carlo simulation method we developed before, is employed here. Result shows that BP is an effective method to position the light source.

  13. Small animal fluorescence and bioluminescence tomography: a review of approaches, algorithms and technology update

    Emerging fluorescence and bioluminescence tomography approaches have several common, yet several distinct features from established emission tomographies of PET and SPECT. Although both nuclear and optical imaging modalities involve counting of photons, nuclear imaging techniques collect the emitted high energy (100–511 keV) photons after radioactive decay of radionuclides while optical techniques count low-energy (1.5–4.1 eV) photons that are scattered and absorbed by tissues requiring models of light transport for quantitative image reconstruction. Fluorescence imaging has been recently translated into clinic demonstrating high sensitivity, modest tissue penetration depth, and fast, millisecond image acquisition times. As a consequence, the promise of quantitative optical tomography as a complement of small animal PET and SPECT remains high. In this review, we summarize the different instrumentation, methodological approaches and schema for inverse image reconstructions for optical tomography, including luminescence and fluorescence modalities, and comment on limitations and key technological advances needed for further discovery research and translation. (topical review)

  14. Small animal fluorescence and bioluminescence tomography: a review of approaches, algorithms and technology update

    Darne, Chinmay; Lu, Yujie; Sevick-Muraca, Eva M.

    2014-01-01

    Emerging fluorescence and bioluminescence tomography approaches have several common, yet several distinct features from established emission tomographies of PET and SPECT. Although both nuclear and optical imaging modalities involve counting of photons, nuclear imaging techniques collect the emitted high energy (100-511 keV) photons after radioactive decay of radionuclides while optical techniques count low-energy (1.5-4.1 eV) photons that are scattered and absorbed by tissues requiring models of light transport for quantitative image reconstruction. Fluorescence imaging has been recently translated into clinic demonstrating high sensitivity, modest tissue penetration depth, and fast, millisecond image acquisition times. As a consequence, the promise of quantitative optical tomography as a complement of small animal PET and SPECT remains high. In this review, we summarize the different instrumentation, methodological approaches and schema for inverse image reconstructions for optical tomography, including luminescence and fluorescence modalities, and comment on limitations and key technological advances needed for further discovery research and translation.

  15. Fluorescence and bioluminescence of bacterial luciferase intermediates

    An intermediate in the luciferase-catalyzed bioluminescent oxidation of FMNH2, isolated and purified by chromatography at --200, was postulated to be an oxygenated reduced flavine-luciferase. Maintained and studied at --20 to --300, this material exhibits a relatively weak fluorescence emission peaking at about 505 nm when excited at 370 nm. It may comprise more than one species. Upon continued exposure to light at 370 nm, the intensity of this fluorescence increases, often by a factor of 5 or more, and its emission spectrum is blue shifted to a maximum at about 485 nm. Upon warming this fluorescence is lost and the fluorescence of flavine mononucleotide appears. If warming is carried out in the presence of a long chain aldehyde, bioluminescence occurs, with the appearance of a similar amount of flavine fluorescence. The bioluminescence yield is about the same with irradiated and nonirradiated samples. The bioluminescence emission spectrum corresponds exactly to the fluorescence emission spectrum of the intermediate formed by irradiation, implicating the latter as being structurally close to the emitting species in bioluminescence. (auth)

  16. Bacteria bioluminescent activity as an indicator of geomagnetic disturbances

    The effect of geomagnetic disturbances and storms on bioluminescence activity of bacterium were investigated. The bioluminescence intensity change depended on amplitude and continuous of geomagnetic storms. It is assumed, that the synchronization of luminous radiation take place in cellos when frequency of geomagnetic disturbances approached to an intrinsic one of a bioluminescence system. High sensitivity of bioluminescence of geomagnetic storms was detected. 5 refs., 4 figs

  17. Real-time image and video processing

    Kehtarnavaz, Nasser

    2006-01-01

    This book presents an overview of the guidelines and strategies for transitioning an image or video processing algorithm from a research environment into a real-time constrained environment. Such guidelines and strategies are scattered in the literature of various disciplines including image processing, computer engineering, and software engineering, and thus have not previously appeared in one place. By bringing these strategies into one place, the book is intended to serve the greater community of researchers, practicing engineers, industrial professionals, who are interested in taking an im

  18. A bioluminescence assay for aldehyde dehydrogenase activity.

    Duellman, Sarah J; Valley, Michael P; Kotraiah, Vinayaka; Vidugiriene, Jolanta; Zhou, Wenhui; Bernad, Laurent; Osterman, Jean; Kimball, Joshua J; Meisenheimer, Poncho; Cali, James J

    2013-03-15

    The aldehyde dehydrogenase (ALDH) family of enzymes is critical for cell survival and adaptation to cellular and environmental stress. These enzymes are of interest as therapeutic targets and as biomarkers of stem cells. This article describes a novel, homogeneous bioluminescence assay to study the activity of the ALDH enzymes. The assay is based on a proluciferin-aldehyde substrate that is recognized and utilized by multiple ALDH enzyme isoforms to generate luciferin. A detection reagent is added to inactivate ALDH and generate light from the luciferin product. The luminescent signal is dependent on the ALDH enzyme concentration and the incubation time in the ALDH reaction; moreover, the luminescent signal generated with the detection reagent is stable for greater than 2 h. This assay provides many advantages over standard NADH fluorescence assays. It is more sensitive and the signal stability provided allows convenient assay setup in batch mode-based high-throughput screens. The assay also shows an accurate pharmacological response for a common ALDH inhibitor and is robust, with a large assay window (S/B=64) and Z'=0.75. PMID:23219557

  19. Generation of a new bioluminescent model for visualisation of mammary tumour development in transgenic mice

    Zagozdzon, Agnieszka M

    2012-05-30

    AbstractBackgroundNumerous transgenic models have been generated to study breast cancer. However, despite many advantages, traditional transgenic models for breast cancer are also burdened with difficulties in early detection and longitudinal observation of transgene-induced tumours, which in most cases are randomly located and occur at various time points. Methods such as palpation followed by mechanical measurement of the tumours are of limited value in transgenic models. There is a crucial need for making these previously generated models suitable for modern methods of tumour visualisation and monitoring, e.g. by bioluminescence-based techniques. This approach was successfully used in the current study.ResultsA new mouse strain (MMTV-Luc2 mice) expressing Luc2 luciferase primarily in mammary tissue in females, with low-level background expression in internal organs, was generated and bred to homozygosity. After these mice were intercrossed with MMTV-PyVT mice, all double transgenic females developed mammary tumours by the age of 10 weeks, the localisation and progression of which could be effectively monitored using the luminescence-based in vivo imaging. Luminescence-based readout allowed for early visualisation of the locally overgrown mammary tissue and for longitudinal evaluation of local progression of the tumours. When sampled ex vivo at the age of 10 weeks, all tumours derived from MMTV-Luc2PyVT females displayed robust bioluminescent signal.ConclusionsWe have created a novel transgenic strain for visualisation and longitudinal monitoring of mammary tumour development in transgenic mice as an addition and\\/or a new and more advanced alternative to manual methods. Generation of this mouse strain is vital for making many of the existing mammary tumour transgenic models applicable for in vivo imaging techniques.

  20. Generation of a new bioluminescent model for visualisation of mammary tumour development in transgenic mice

    Zagozdzon Agnieszka M

    2012-05-01

    Full Text Available Abstract Background Numerous transgenic models have been generated to study breast cancer. However, despite many advantages, traditional transgenic models for breast cancer are also burdened with difficulties in early detection and longitudinal observation of transgene-induced tumours, which in most cases are randomly located and occur at various time points. Methods such as palpation followed by mechanical measurement of the tumours are of limited value in transgenic models. There is a crucial need for making these previously generated models suitable for modern methods of tumour visualisation and monitoring, e.g. by bioluminescence-based techniques. This approach was successfully used in the current study. Results A new mouse strain (MMTV-Luc2 mice expressing Luc2 luciferase primarily in mammary tissue in females, with low-level background expression in internal organs, was generated and bred to homozygosity. After these mice were intercrossed with MMTV-PyVT mice, all double transgenic females developed mammary tumours by the age of 10 weeks, the localisation and progression of which could be effectively monitored using the luminescence-based in vivo imaging. Luminescence-based readout allowed for early visualisation of the locally overgrown mammary tissue and for longitudinal evaluation of local progression of the tumours. When sampled ex vivo at the age of 10 weeks, all tumours derived from MMTV-Luc2PyVT females displayed robust bioluminescent signal. Conclusions We have created a novel transgenic strain for visualisation and longitudinal monitoring of mammary tumour development in transgenic mice as an addition and/or a new and more advanced alternative to manual methods. Generation of this mouse strain is vital for making many of the existing mammary tumour transgenic models applicable for in vivo imaging techniques.

  1. Generation of a new bioluminescent model for visualisation of mammary tumour development in transgenic mice

    Numerous transgenic models have been generated to study breast cancer. However, despite many advantages, traditional transgenic models for breast cancer are also burdened with difficulties in early detection and longitudinal observation of transgene-induced tumours, which in most cases are randomly located and occur at various time points. Methods such as palpation followed by mechanical measurement of the tumours are of limited value in transgenic models. There is a crucial need for making these previously generated models suitable for modern methods of tumour visualisation and monitoring, e.g. by bioluminescence-based techniques. This approach was successfully used in the current study. A new mouse strain (MMTV-Luc2 mice) expressing Luc2 luciferase primarily in mammary tissue in females, with low-level background expression in internal organs, was generated and bred to homozygosity. After these mice were intercrossed with MMTV-PyVT mice, all double transgenic females developed mammary tumours by the age of 10 weeks, the localisation and progression of which could be effectively monitored using the luminescence-based in vivo imaging. Luminescence-based readout allowed for early visualisation of the locally overgrown mammary tissue and for longitudinal evaluation of local progression of the tumours. When sampled ex vivo at the age of 10 weeks, all tumours derived from MMTV-Luc2PyVT females displayed robust bioluminescent signal. We have created a novel transgenic strain for visualisation and longitudinal monitoring of mammary tumour development in transgenic mice as an addition and/or a new and more advanced alternative to manual methods. Generation of this mouse strain is vital for making many of the existing mammary tumour transgenic models applicable for in vivo imaging techniques

  2. Compact snapshot real-time imaging spectrometer

    Kudenov, Michael W.; Dereniak, Eustace L.

    2011-11-01

    The described spectral imaging system, referred to as a Snapshot Hyperspectral Imaging Fourier Transform (SHIFT) spectrometer, is capable of acquiring spectral image data of a scene in a single integration of a camera, is ultra-compact, inexpensive (commercial off-the-shelf), has no moving parts, and can produce datacubes (x, y, λ) in real time. Based on the multiple-image FTS originally developed by A. Hirai [1], the presented device offers significant advantages over his original implementation. Namely, its birefringent nature results in a common-path interferometer which makes the spectrometer insensitive to vibration. Furthermore, it enables the potential of making the instrument ultra-compact, thereby improving the portability of the sensor. By combining a birefringent interferometer with a lenslet array, the entire spectrometer consumes approximately 15×15×20 mm3, excluding the imaging camera. The theory of the birefringent FTS is provided, followed by details of its specific embodiment and a laboratory proof of concept of the sensor. Post-processing is currently accomplished in Matlab, but progress is underway in developing real-time reconstruction capabilities with software programmed on a graphics processing unit (GPU). It is anticipated that processing of >30 datacubes per second can be achieved with modest GPU hardware, with spatial/spectral data of or exceeding 256×256 spatial resolution elements and 60 spectral bands over the visible (400-800 nm) spectrum. Data were collected outdoors, demonstrating the sensor's ability to resolve spectral signatures in standard outdoor lighting and environmental conditions as well as retinal imaging.

  3. Monitoring of environmental pollutants by bioluminescent bacteria.

    Girotti, Stefano; Ferri, Elida Nora; Fumo, Maria Grazia; Maiolini, Elisabetta

    2008-02-01

    This review deals with the applications of bioluminescent bacteria to the environmental analyses, published during the years 2000-2007. The ecotoxicological assessment, by bioassays, of the environmental risks and the luminescent approaches are reported. The review includes a brief introduction to the characteristics and applications of bioassays, a description of the characteristics and applications of natural bioluminescent bacteria (BLB), and a collection of the main applications to organic and inorganic pollutants. The light-emitting genetically modified bacteria applications, as well as the bioluminescent immobilized systems and biosensors are outlined. Considerations about commercially available BLB and BLB catalogues are also reported. Most of the environmental applications, here mentioned, of luminescent organisms are on wastewater, seawater, surface and ground water, tap water, soil and sediments, air. Comparison to other bioindicators and bioassay has been also made. Various tables have been inserted, to make easier to take a rapid glance at all possible references concerning the topic of specific interest. PMID:18206990

  4. Optimal integration time in OCT imaging

    Martin, Lorenz; Grub, Stephan; Meier, Christoph

    2015-07-01

    When measuring static objects with 3D OCT, two opposing trends occur: If the integration time is too short, the measurement is noisy resulting in granulated textures on measured objects. If the integration time is too long, drifts e.g. due to thermal effects or unstable laser sources lead to blurred images. The Allan variance is a scheme to find the optimal integration time in terms of reducing noise without picking up signal drift. A long-term measurement with short integration time of a reference target under realistic conditions is needed to obtain the database for the calculation of the Allan variance. Longer integration times are simulated by taking averages of subsequent samples. The Allan variance being the mean of the squared differences between two consecutive averages is calculated for different integration times. The optimal integration time is achieved for minimal Allan variance. First, the scheme is explained and discussed with simulated data. Then, reference measurements of layers of adhesive tape made with a 3D OCT device are analysed to find the optimal integration time of the device. Finally, the findings are applied to the detection of water inclusions in calcite. With too short integration time the water inclusions appear with a stained surface. With the integration time increased towards the optimal time, the surfaces of the water inclusions get smoother and easier to discriminate from the background. Ready-to-use Octave code for the computation of the Allan variance is provided.

  5. NanoLuc reporter for dual luciferase imaging in living animals.

    Stacer, Amanda C; Nyati, Shyam; Moudgil, Pranav; Iyengar, Rahul; Luker, Kathryn E; Rehemtulla, Alnawaz; Luker, Gary D

    2013-10-01

    Bioluminescence imaging is widely used for cell-based assays and animal imaging studies in biomedical research and drug development, capitalizing on the high signal to background of this technique. A relatively small number of luciferases are available for imaging studies, substantially limiting the ability to image multiple molecular and cellular events, as done commonly with fluorescence imaging. To advance dual reporter bioluminescence molecular imaging, we tested a recently developed, adenosine triphosphate–independent luciferase enzyme from Oplophorus gracilirostris (NanoLuc [NL]) as a reporter for animal imaging. We demonstrated that NL could be imaged in superficial and deep tissues in living mice, although the detection of NL in deep tissues was limited by emission of predominantly blue light by this enzyme. Changes in bioluminescence from NL over time could be used to quantify tumor growth, and secreted NL was detectable in small volumes of serum. We combined NL and firefly luciferase reporters to quantify two key steps in transforming growth factor β signaling in intact cells and living mice, establishing a novel dual luciferase imaging strategy for quantifying signal transduction and drug targeting. Our results establish NL as a new reporter for bioluminescence imaging studies in intact cells and living mice that will expand imaging of signal transduction in normal physiology, disease, and drug development. PMID:24371848

  6. Chemistry and biology of insect bioluminescence

    Basic aspects on the Chemistry and Biology of bioluminescence are reviewed, with emphasis on insects. Data from the investigation of Lampyridae (fireflies) are collected from literature. With regard to Elateridae (click beetles) and Phengodidae (rail road worms), the least explored families of luminescent insects, new data are presented on the following aspects: (i) 'in vivo' emission spectra, (ii) chemical nature of the luciferin, (iii) conection between bioluminescence and 'oxygen toxicity' as a result of molecular oxygen storage and (iv) the role of light emission by larvae and pupae. (Author)

  7. Interactive Real-time Magnetic Resonance Imaging

    Brix, Lau

    Real-time acquisition, reconstruction and interactively changing the slice position using magnetic resonance imaging (MRI) have been possible for years. However, the current clinical use of interactive real-time MRI is limited due to an inherent low spatial and temporal resolution. This PhD project...... seeks to implement and assess existing reconstruction algorithms using multi-processors of modern graphics cards and many-core computer processors and to cover some of the potential clinical applications which might benefit from using an interactive real-time MRI system. First an off-line, but...... interactive, slice alignment tool was used to support the notion that 3D blood flow quantification in the heart possesses the ability to obtain curves and volumes which are not statistical different from standard 2D flow. Secondly, the feasibility of an interactive real-time MRI system was exploited with...

  8. Time Variant Change Analysis in Satellite Images

    Rachita Sharma

    2013-05-01

    Full Text Available This paper describes the time variant changes in satellite images using Self Organizing Feature Map (SOFM technique associated with Artificial Neural Network. In this paper, we take a satellite image and find the time variant changes using above technique with the help of MATLAB. This paper reviews remotely sensed data analysis with neural networks. First, we present an overview of the main concepts underlying Artificial Neural Networks (ANNs, including the main architectures and learning algorithms. Then, the main tasks that involve ANNs in remote sensing are described. We first make a brief introduction to models of networks, for then describing in general terms Artificial Neural Networks (ANNs. As an application, we explain the back propagation algorithm, since it is widely used and many other algorithms are derived from it. There are two techniques that are used for classification in pattern recognition such as Supervised Classification and Unsupervised Classification. In supervised learning technique the network knows about the target and it has to change accordingly to get the desired output corresponding to the presented input sample data. Most of the previous work has already been done on supervised classification. In this study we are going to present the classification of satellite images using unsupervised classification method of ANN.

  9. Time-domain flaw imaging system

    L. Medina

    2005-01-01

    Full Text Available Ultrasonic Non Destructive Evaluation of materials is a useful tool for flaw detection and characterization. A typical ultrasonic imaging system may consist of a single transducer or an array of sensors working in a B-scan mode. This mode operates by transmitting a pulse of train of pulses from several locations and detecting the echoes coming from in-homogeneities. The reflected energy can be represented as a map of ultrasonic reflectivity. A time-delay beamformer has been successfully used to reconstruct the image, and localize the inhomogeneities within the scanned medium, by time shifting the signals, and summing them up. This process enables to locate regions at which signals are added constructively. It is however, a time consuming process and requires =2 distance of motor steps or inter-element distance between array elements. An algorithm based on time-domain envelope beamformer is presented here. This algorithm is able to diminish the number of computational operations without losing relevant information about the location of in-homogeneities. A comparison between classical and envelope beam-formers is presented when applied to sets of simulated signals. Lateral and longitudinal resolutions are also computed when two targets are within the scanned medium.

  10. Improving medical imaging report turnaround times.

    Marquez, Luis O

    2005-01-01

    Southern Ohio Medical Center (SOMC), a 232-bed community-based teaching hospital, is equipped with state-of-the-art equipment such as 2 16-slice computed tomography (CT) scanners, 3 MR scanners, 3 ultrasound scanners, 2 digital mammography units, and 3 nuclear medicine cameras. One hundred twenty-six employees--ranging from support personnel to technologists along with 7 board-certified radiologists--staff the medical imaging department. Procedure volume is approximately 164,000 per year and is performed in all American College of Radiology (ACR)-accredited modalities. Filmless since 1998, SOMC's medical imaging department has resulted in productivity gains to the estimated 164,000 procudures for fiscal year 2005. The catalyst for the department is a robust picture archiving and communication system (PACS). Working with the radiologists, staff, and transcription services, turnaround time was reduced to from 13 hours to 9 hours from exam start to report sign off. Additional technology intervention was essential to further decrease report turnaround time. SOMC served as a beta site for a radiology information system (RIS). The new RIS has allowed the medical imaging department to move from a paper department to a "pseudo paperless" department. Orders, history sheets, consents, and other forms are scanned into the RIS for staff and radiologist use. Requisitions are no longer printed, and staff has access to review workstations to ensure that patients are called back into the department for procedures. This new workflow has also reduced paper traffic within the department. The last piece of the technology puzzle to improve report turnaround time was voice recognition technology. From its implementation, voice recognition enhanced the RIS technology. All of the radiologists began to use the product as soon as it was available. They perform all the editing and corrections either by voice command or by manual typing. The medical imaging department has noted that voice command corrections and editing are more efficient for the radiologist. The overall impact on decreased radiology report turnaround times is not only seen in medical imaging, but also has a global affect within the hospital. SOMC plans to realize a reduction length of patient stays, and a faster process for plotting the course of patient treatment, e.g., faster visits from emergency department (ED) physicians to patients. PMID:15794377

  11. Modeling bioluminescent photon transport in tissue based on Radiosity-diffusion model

    Sun, Li; Wang, Pu; Tian, Jie; Zhang, Bo; Han, Dong; Yang, Xin

    2010-03-01

    Bioluminescence tomography (BLT) is one of the most important non-invasive optical molecular imaging modalities. The model for the bioluminescent photon propagation plays a significant role in the bioluminescence tomography study. Due to the high computational efficiency, diffusion approximation (DA) is generally applied in the bioluminescence tomography. But the diffusion equation is valid only in highly scattering and weakly absorbing regions and fails in non-scattering or low-scattering tissues, such as a cyst in the breast, the cerebrospinal fluid (CSF) layer of the brain and synovial fluid layer in the joints. A hybrid Radiosity-diffusion model is proposed for dealing with the non-scattering regions within diffusing domains in this paper. This hybrid method incorporates a priori information of the geometry of non-scattering regions, which can be acquired by magnetic resonance imaging (MRI) or x-ray computed tomography (CT). Then the model is implemented using a finite element method (FEM) to ensure the high computational efficiency. Finally, we demonstrate that the method is comparable with Mont Carlo (MC) method which is regarded as a 'gold standard' for photon transportation simulation.

  12. Sparsity reconstruction for bioluminescence tomography based on an augmented Lagrangian method

    Guo, Wei; Jia, Kebin; Tian, Jie; Han, Dong; Liu, Xueyan; Liu, Kai; Zhang, Qian; Feng, Jinchao; Qin, Chenghu

    2012-03-01

    Bioluminescence imaging (BLI) is an optical molecular imaging modality for monitoring physiological and pathological activities at the molecular level. The information of bioluminescent probe distribution in small animals can be threedimensionally and quantitatively obtained by bioluminescence tomography (BLT). Due to ill-posed nature, BLT may bear multiple solutions and aberrant reconstruction in the presence of measurement noise and optical parameter mismatches. Among different regularization methods, L2-type regularization strategy is the most popular and commonly-applied method, which minimizes the output-least-square formulation incorporated with the l2-norm regularization term to stabilize the problem. However, it often imposes over-smoothing on the reconstruction results. In contrast, for many practical applications, such as early detection of tumors, the volumes of the bioluminescent sources are very small compared with the whole body. In this paper, L1 regularization is used to fully take advantage of the sparsity prior knowledge and improve both efficiency and stability. And then a reconstruction method based on the augmented Lagrangian approach is proposed, which considers the BLT problem as the constrained optimization problem and employs the Bregman iterative method to deal with it. By using "divide and conquer" approach, the optimization problem can be exactly and fast solved by iteratively solving a sequence of unconstrained subproblems. To evaluate the performance of the proposed method in turbid mouse geometry, stimulate experiments with a heterogeneous 3D mouse atlas are conducted. In addition, physical experiments further demonstrate the potential of the proposed algorithm in practical applications.

  13. Real-Time Imaging of Quantum Entanglement

    Full text: Photonic entanglement of spatial modes is routinely studied in many experiments and offers interesting features for quantum optical and quantum information experiments. To investigate the properties of these complex modes, it is crucial to gain information about the transversal structure with high precision and in an efficient way. We show that modern technology, namely triggered intensified charge coupled device (ICCD) cameras are fast and sensitive enough to image in real-time the effect of the measurement of one photon on the spatial mode of its entangled partner photon. We determine from imaged intensity pattern the number of photons within a certain region, evaluate its error margin and thereby quantitatively verify the non-classicality of the measurements. In addition, the use of the ICCD camera allows us to demonstrate visually the enhanced remote angular sensing and the high flexibility of our setup in creating any desired spatial-mode entanglement. (author)

  14. Papyrus imaging with terahertz time domain spectroscopy

    Labaune, J.; Jackson, J. B.; Pagès-Camagna, S.; Duling, I. N.; Menu, M.; Mourou, G. A.

    2010-09-01

    Terahertz time domain spectroscopic imaging (THz-TDSI) is a non-ionizing, non-contact and non-destructive measurement technique that has been recently utilized to study cultural heritage artifacts. We will present this technique and the results of non-contact measurements of papyrus texts, including images of hidden papyri. Inks for modern papyrus specimens were prepared using the historical binder, Arabic gum, and two common pigments used to write ancient texts, carbon black and red ochre. The samples were scanned in reflection at normal incidence with a pulse with a spectral range between 0.1 and 1.5 THz. Temporal analysis of the signals provides the depths of the layers, and their frequency spectra give information about the inks.

  15. A Multi-Camera System for Bioluminescence Tomography in Preclinical Oncology Research

    Lewis, Matthew A.; Richer, Edmond; Slavine, Nikolai V.; Kodibagkar, Vikram D.; Soesbe, Todd C.; Antich, Peter P.; Mason, Ralph P.

    2013-01-01

    Bioluminescent imaging (BLI) of cells expressing luciferase is a valuable noninvasive technique for investigating molecular events and tumor dynamics in the living animal. Current usage is often limited to planar imaging, but tomographic imaging can enhance the usefulness of this technique in quantitative biomedical studies by allowing accurate determination of tumor size and attribution of the emitted light to a specific organ or tissue. Bioluminescence tomography based on a single camera with source rotation or mirrors to provide additional views has previously been reported. We report here in vivo studies using a novel approach with multiple rotating cameras that, when combined with image reconstruction software, provides the desired representation of point source metastases and other small lesions. Comparison with MRI validated the ability to detect lung tumor colonization in mouse lung.

  16. Bioluminescence: diplôme 2015

    Giachino, Vincent; Geiser, Martial

    2016-01-01

    Dans le cadre du projet européen BRAAVOO, qui vise à mesurer les concentrations de différents polluants présents dans la mer, nous développons un lecteur de bioluminescence embarqué dans une bouée.

  17. Bioluminescent Bioreporters Encapsulated in Silica Gel

    Kuncová, Gabriela; Trögl, J.; Demnerová, K.; Ripp, S.; Sayler, G. S.

    - : -, 2008, O08-2 - 1-O08-2 - 4. [XVI International Conference on Bioencapsulation. Dublin (IE), 04.09.2008-06.09.2008] Institutional research plan: CEZ:AV0Z40720504 Keywords : bioluminescent bioreporter * silica gel * biosensor Subject RIV: CE - Biochemistry

  18. In vivo bioluminescence tomography based on multi-view projection and 3D surface reconstruction

    Zhang, Shuang; Wang, Kun; Leng, Chengcai; Deng, Kexin; Hu, Yifang; Tian, Jie

    2015-03-01

    Bioluminescence tomography (BLT) is a powerful optical molecular imaging modality, which enables non-invasive realtime in vivo imaging as well as 3D quantitative analysis in preclinical studies. In order to solve the inverse problem and reconstruct inner light sources accurately, the prior structural information is commonly necessary and obtained from computed tomography or magnetic resonance imaging. This strategy requires expensive hybrid imaging system, complicated operation protocol and possible involvement of ionizing radiation. The overall robustness highly depends on the fusion accuracy between the optical and structural information. In this study we present a pure optical bioluminescence tomographic system (POBTS) and a novel BLT method based on multi-view projection acquisition and 3D surface reconstruction. The POBTS acquired a sparse set of white light surface images and bioluminescent images of a mouse. Then the white light images were applied to an approximate surface model to generate a high quality textured 3D surface reconstruction of the mouse. After that we integrated multi-view luminescent images based on the previous reconstruction, and applied an algorithm to calibrate and quantify the surface luminescent flux in 3D.Finally, the internal bioluminescence source reconstruction was achieved with this prior information. A BALB/C mouse with breast tumor of 4T1-fLuc cells mouse model were used to evaluate the performance of the new system and technique. Compared with the conventional hybrid optical-CT approach using the same inverse reconstruction method, the reconstruction accuracy of this technique was improved. The distance error between the actual and reconstructed internal source was decreased by 0.184 mm.

  19. Enhanced Landweber algorithm via Bregman iterations for bioluminescence tomography

    Xia, Yi; Zhang, Meng

    2014-09-01

    Bioluminescence tomography (BLT) is an important optical molecular imaging modality aimed at visualizing physiological and pathological processes at cellular and molecular levels. While the forward process of light propagation is described by the diffusion approximation to radiative transfer equation, BLT is the inverse problem to reconstruct the 3D localization and quantification of internal bioluminescent sources distribution. Due to the inherent ill-posedness of the BLT problem, regularization is generally indispensable to obtain more favorable reconstruction. In particular, total variation (TV) regularization is known to be effective for piecewise-constant source distribution which can permit sharp discontinuities and preserve edges. However, total variation regularization generally suffers from the unsatisfactory staircasing effect. In this work, we introduce the Bregman iterative regularization to alleviate this degeneration and enhance the numerical reconstruction of BLT. Based on the existing Landweber method (LM), we put forward the Bregman-LM-TV algorithm for BLT. Numerical experiments are carried out and preliminary simulation results are reported to evaluate the proposed algorithms. It is found that Bregman-LM-TV can significantly outperform the individual Landweber method for BLT when the source distribution is piecewise-constant.

  20. Vector processing enhancements for real-time image analysis

    A real-time image analysis system was developed for beam imaging diagnostics. An Apple Power Mac G5 with an Active Silicon LFG frame grabber was used to capture video images that were processed and analyzed. Software routines were created to utilize vector-processing hardware to reduce the time to process images as compared to conventional methods. These improvements allow for more advanced image processing diagnostics to be performed in real time.

  1. Vector processing enhancements for real-time image analysis.

    Shoaf, S.; APS Engineering Support Division

    2008-01-01

    A real-time image analysis system was developed for beam imaging diagnostics. An Apple Power Mac G5 with an Active Silicon LFG frame grabber was used to capture video images that were processed and analyzed. Software routines were created to utilize vector-processing hardware to reduce the time to process images as compared to conventional methods. These improvements allow for more advanced image processing diagnostics to be performed in real time.

  2. Time-Lapse Imaging of Cell Death.

    Wallberg, Fredrik; Tenev, Tencho; Meier, Pascal

    2016-01-01

    The best approach to distinguish between necrosis and apoptosis is time-lapse video microscopy. This technique enables a biological process to be photographed at regular intervals over a period, which may last from a few hours to several days, and can be applied to cells in culture or in vivo. We have established two time-lapse microscopy methods based on different ways of calculating cell death: semiautomated and automated. In the semiautomated approach, cell death can be visualized by staining with combinations of Alexa Fluor 647-conjugated Annexin V and Sytox Green (SG), or Annexin V(FITC) and Propidium iodide (PI). The automated method is similar except that all cells are labeled with dyes. This allows faster quantification of data. To this end Cell Tracker Green is used to label all cells at time zero in combination with PI and Alexa Fluor 647-conjugated Annexin V. Necrotic cell death is accompanied by either simultaneous labeling with Annexin V and PI or SG (double-positive), or direct PI or SG staining. Additionally, necrotic cells display characteristic morphology, such as cytoplasmic swelling. In contrast to necrosis where membrane permeabilization is an early event, cells that die by apoptosis lose their membrane permeability relatively late. Therefore, the time between Annexin V staining and PI or SG uptake (double-positive) can be used to distinguish necrosis from apoptosis. This protocol describes the analysis of cell death by time-lapse imaging of HT1080 and L929 cells stained with these dyes, but it can be readily adapted to other cell types of interest. PMID:26933245

  3. Bacterial bioluminescence response to long-term exposure to reverse osmosis treated effluents from dye industries

    Ravindran, J.; Manikandan, B.; Shirodkar, P; Francis, K; ManiMurali, R.; Vethamony, P

    The bacterial bioluminescence assay is one of the novel means for toxicity detection. The bioluminescence response of 2 marine bioluminescent bacteria was tested upon their long-term exposure to 9 different reverse osmosis (RO) rejects with varying...

  4. Reliability of a bioluminescence ATP assay for detection of bacteria.

    Selan, L.; Berlutti, F; Passariello, C.; Thaller, M C; Renzini, G

    1992-01-01

    The reliability of bioluminescence assays which employ the luciferin-luciferase ATP-dependent reaction to evaluate bacterial counts was studied, both in vitro and on urine specimens. Bioluminescence and cultural results for the most common urinary tract pathogens were analyzed. Furthermore, the influence of the culture medium, of the assaying method, and of the phase of growth on bioluminescence readings was studied. Results show that Proteus, Providencia, and Morganella strains are not corre...

  5. Bubble stimulation efficiency of dinoflagellate bioluminescence.

    Deane, Grant B; Stokes, M Dale; Latz, Michael I

    2016-02-01

    Dinoflagellate bioluminescence, a common source of bioluminescence in coastal waters, is stimulated by flow agitation. Although bubbles are anecdotally known to be stimulatory, the process has never been experimentally investigated. This study quantified the flash response of the bioluminescent dinoflagellate Lingulodinium polyedrum to stimulation by bubbles rising through still seawater. Cells were stimulated by isolated bubbles of 0.3-3 mm radii rising at their terminal velocity, and also by bubble clouds containing bubbles of 0.06-10 mm radii for different air flow rates. Stimulation efficiency, the proportion of cells producing a flash within the volume of water swept out by a rising bubble, decreased with decreasing bubble radius for radii less than approximately 1 mm. Bubbles smaller than a critical radius in the range 0.275-0.325 mm did not stimulate a flash response. The fraction of cells stimulated by bubble clouds was proportional to the volume of air in the bubble cloud, with lower stimulation levels observed for clouds with smaller bubbles. An empirical model for bubble cloud stimulation based on the isolated bubble observations successfully reproduced the observed stimulation by bubble clouds for low air flow rates. High air flow rates stimulated more light emission than expected, presumably because of additional fluid shear stress associated with collective buoyancy effects generated by the high air fraction bubble cloud. These results are relevant to bioluminescence stimulation by bubbles in two-phase flows, such as in ship wakes, breaking waves, and sparged bioreactors. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26061152

  6. Transformation Experiment Using Bioluminescence Genes of "Vibrio fischeri."

    Slock, James

    1995-01-01

    Bioluminescence transformation experiments show students the excitement and power of recombinant DNA technology. This laboratory experiment utilizes two plasmids of "Vibrio fischeri" in a transformation experiment. (LZ)

  7. A Causal Relation between Bioluminescence and Oxygen to Quantify the Cell Niche

    Lambrechts, Dennis; Roeffaers, Maarten; Goossens, Karel; Hofkens, Johan; Vande Velde, Greetje; Van de Putte, Tom; Schrooten, Jan; Van Oosterwyck, Hans

    2014-01-01

    Bioluminescence imaging assays have become a widely integrated technique to quantify effectiveness of cell-based therapies by monitoring fate and survival of transplanted cells. To date these assays are still largely qualitative and often erroneous due to the complexity and dynamics of local micro-environments (niches) in which the cells reside. Here, we report, using a combined experimental and computational approach, on oxygen that besides being a critical niche component res...

  8. Dual monitoring using 124I-FIAU and bioluminescence for HSV1-tk suicide gene therapy

    Herpes simplex virus type I thymidine kinase (HSV-tk) is the most common reporter gene and is used in cancer gene therapy with a prodrug nucleoside analog, ganciclovir (GCV). The aim of this study is to evaluate therapeutic efficacy of suicide gene therapy with 2'-fluoro-2'-deoxy-1-D-arabinofuranosyl-5-[124I] iodouracil (124I - FIAU) and bioluminescence in retrovirally HSV -tk and firefly luciferase transduced hepatoma model. The HSV -tk and firefly luciferase (Luc) was retrovirally transduced and expressed in MCA rat Morris hepatoma cells. Nude mice with subcutaneous tumors, MCA and MCA-TK-Luc, were subjected to GCV treatment (50mg/Kg/d intraperitoneally) for 5 day. PET imaging and biodistribution with (124I-FIAU) were performed at before and after initiation of therapy with GCV. Bioluminescent signal was also measured during GCV treatment. Before GCV treatment, no significant difference in tumor volume was found in tumors between MCA and MCA-TK-Luc. After GCV treatment, tumor volume of MCA-TK-Luc markedly reduced compared to that of MCA. In biodistribution study, 124I-FIAU uptake after GCV therapy significantly decreased compared with pretreatment levels (34.8 13.67 %ID/g vs 7.6 2.59 %ID/g) and bioluminescent signal was also significantly decreased compared with pretreatment levels. In small animal PET imaging, 124I-FIAU selectively localized in HSV -tk expressing tumor and the therapeutic efficacy of GCV treatment was evaluated by 124I-FIAU PET imaging. 124I-FIAU PET and bioluminescence imaging in HSV-tk suicide gene therapy were effective to evaluate the therapeutic response. 124I-FIAU may serve as an efficient and selective agent for monitoring of transduced HSV1-tk gene expression in vivo in clinical trials

  9. Highly sensitive real-time in vivo imaging of an influenza reporter virus reveals dynamics of replication and spread.

    Tran, Vy; Moser, Lindsey A; Poole, Daniel S; Mehle, Andrew

    2013-12-01

    The continual public health threat posed by the emergence of novel influenza viruses necessitates the ability to rapidly monitor infection and spread in experimental systems. To analyze real-time infection dynamics, we have created a replication-competent influenza reporter virus suitable for in vivo imaging. The reporter virus encodes the small and bright NanoLuc luciferase whose activity serves as an extremely sensitive readout of viral infection. This virus stably maintains the reporter construct and replicates in culture and in mice with near-native properties. Bioluminescent imaging of the reporter virus permits serial observations of viral load and dissemination in infected animals, even following clearance of a sublethal challenge. We further show that the reporter virus recapitulates known restrictions due to host range and antiviral treatment, suggesting that this technology can be applied to studying emerging influenza viruses and the impact of antiviral interventions on infections in vivo. These results describe a generalizable method to quickly determine the replication and pathogenicity potential of diverse influenza strains in animals. PMID:24089552

  10. Is it time for cardiac innervation imaging?

    Knuuti, J. [Turku Univ., Turku (Finland) Turku PET Center; Sipola, P. [Kuopio Univ., Kuopio (Finland)

    2005-03-01

    The autonomic nervous system plays an important role in the regulation of cardiac function and the regional distribution of cardiac nerve terminals can be visualized using scintigraphic techniques. The most commonly used tracer is iodine-123-metaiodobenzylguanidine (MIBG) but C-11-hydroxyephedrine has also been used with PET. When imaging with MIBG, the ratio of heart-to-mediastinal counts is used as an index of tracer uptake, and regional distribution is also assessed from tomographic images. The rate of clearance of the tracer can also be measured and indicates the function of the adrenergic system. Innervation imaging has been applied in patients with susceptibility to arrythmias, coronary artery disease, hypertrophic and dilated cardiomyopathy and anthracycline induced cardiotoxicity. Abnormal adrenergic innervation or function appear to exist in many pathophysiological conditions indicating that sympathetic neurons are very susceptible to damage. Abnormal findings in innervation imaging also appear to have significant prognostic value especially in patients with cardiomyopathy. Recently, it has also been shown that innervation imaging can monitor drug-induced changes in cardiac adrenergic activity. Although innervation imaging holds great promise for clinical use, the method has not received wider clinical acceptance. Larger randomized studies are required to confirm the value of innervation imaging in various specific indications.

  11. Unsupervised learning assisted robust prediction of bioluminescent proteins.

    Nath, Abhigyan; Subbiah, Karthikeyan

    2016-01-01

    Bioluminescence plays an important role in nature, for example, it is used for intracellular chemical signalling in bacteria. It is also used as a useful reagent for various analytical research methods ranging from cellular imaging to gene expression analysis. However, identification and annotation of bioluminescent proteins is a difficult task as they share poor sequence similarities among them. In this paper, we present a novel approach for within-class and between-class balancing as well as diversifying of a training dataset by effectively combining unsupervised K-Means algorithm with Synthetic Minority Oversampling Technique (SMOTE) in order to achieve the true performance of the prediction model. Further, we experimented by varying different levels of balancing ratio of positive data to negative data in the training dataset in order to probe for an optimal class distribution which produces the best prediction accuracy. The appropriately balanced and diversified training set resulted in near complete learning with greater generalization on the blind test datasets. The obtained results strongly justify the fact that optimal class distribution with a high degree of diversity is an essential factor to achieve near perfect learning. Using random forest as the weak learners in boosting and training it on the optimally balanced and diversified training dataset, we achieved an overall accuracy of 95.3% on a tenfold cross validation test, and an accuracy of 91.7%, sensitivity of 89. 3% and specificity of 91.8% on a holdout test set. It is quite possible that the general framework discussed in the current work can be successfully applied to other biological datasets to deal with imbalance and incomplete learning problems effectively. PMID:26599828

  12. Iterative reconstruction for bioluminescence tomography with total variation regularization

    Jin, Wenma; He, Yonghong

    2012-12-01

    Bioluminescence tomography(BLT) is an instrumental molecular imaging modality designed for the 3D location and quantification of bioluminescent sources distribution in vivo. In our context, the diffusion approximation(DA) to radiative transfer equation(RTE) is utilized to model the forward process of light propagation. Mathematically, the solution uniqueness does not hold for DA-based BLT which is an inverse source problem of partial differential equations and hence is highly ill-posed. In the current work, we concentrate on a general regularization framework for BLT with Bregman distance as data fidelity and total variation(TV) as regularization. Two specializations of the Bregman distance, the least squares(LS) distance and Kullback-Leibler(KL) divergence, which correspond to the Gaussian and Poisson environments respectively, are demonstrated and the resulting regularization problems are denoted as LS+TV and KL+TV. Based on the constrained Landweber(CL) scheme and expectation maximization(EM) algorithm for BLT, iterative algorithms for the LS+TV and KL+TV problems in the context of BLT are developed, which are denoted as CL-TV and EM-TV respectively. They are both essentially gradient-based algorithms alternatingly performing the standard CL or EM iteration step and the TV correction step which requires the solution of a weighted ROF model. Chambolle's duality-based approach is adapted and extended to solving the weighted ROF subproblem. Numerical experiments for a 3D heterogeneous mouse phantom are carried out and preliminary results are reported to verify and evaluate the proposed algorithms. It is found that for piecewise-constant sources both CL-TV and EM-TV outperform the conventional CL and EM algorithms for BLT.

  13. Detection of ATP and NADH: A Bioluminescent Experience.

    Selig, Ted C.; And Others

    1984-01-01

    Described is a bioluminescent assay for adenosine triphosphate (ATP) and reduced nicotineamide-adenine dinucleotide (NADH) that meets the requirements of an undergraduate biochemistry laboratory course. The 3-hour experiment provides students with experience in bioluminescence and analytical biochemistry yet requires limited instrumentation,…

  14. A REVIEW OF ENVIRONMENTAL APPLICATIONS OF BIOLUMINESCENCE MEASUREMENTS

    This review of the recent literature on environmental applications of bioluminescence systems will focus on in vivo and in vitro bioluminescence methods that have been utilized to elucidate properties of chemicals, toxic and mutagenic effects, and to estimate biomass. The unifyin...

  15. Use of the liquid scintillation spectrometer in bioluminescence analysis

    This review covers publications concerning analytical bioluminescence which in the main have appeared between mid-1973 and mid-1976. Outlines of some new assays and techniques are given together with modifications of existing procedures. Comments are presented on the use of the liquid scintillation spectrometer and other equipment for measuring bioluminescence. New applications are detailed and discussed

  16. Dinoflagellate bioluminescence in response to mechanical stimuli in water flows

    A. S. Cussatlegras

    2005-01-01

    Full Text Available Bioluminescence of plankton organisms induced by water movements has long been observed and is still under investigations because of its great complexity. In particular, the exact mechanism occurring at the level of the cell has not been yet fully understood. This work is devoted to the study of the bioluminescence of the dinoflagellates plankton species Pyrocystis noctiluca in response to mechanical stimuli generated by water flows. Several experiments were performed with different types of flows in a Couette shearing apparatus. All of them converge to the conclusion that stationary homogeneous laminar shear does not trigger massive bioluminescence, but that acceleration and shear are both necessary to stimulate together an intense bioluminescence response. The distribution of the experimental bioluminescence thresholds is finally calculated from the light emission response for the Pyrocystis noctiluca species.

  17. Terahertz quasi-near-field real-time imaging

    Wang, Xinke; Cui, Ye; Hu, Dan; Sun, Wenfeng; Ye, JiaSheng; Zhang, Yan

    2009-12-01

    A terahertz (THz) quasi-near-field real-time imaging system is presented. Not only the consumption of experimental time is dramatically reduced, but also the resolution of the imaging system is improved to the magnitude of sub-wavelength of THz waves. THz images of a razor blade edge are obtained and the spatial resolution of the imaging system is discussed in detail. For checking the imaging capability of this system, three metallic plates with different sub-wavelength air hole arrays are imaged and the microstructure of these samples can be clearly observed in their THz images. It is believed that the THz quasi-near-field real-time imaging system should have tremendous applications in the THz microscopic field.

  18. Mining Satellite Image Time Series: Statistical Modeling and Evolution Analysis

    Cui , Shiyong; Datcu, Mihai

    2011-01-01

    Due to the short revisit time of high resolution satellites, huge amount of high resolution satellite images can be acquired every few days even few hours. It promotes the construction of Satellite Image Time Series (SITS), which contain valuable spatio-temporal information. Therefore, it is strongly needed to develop methods to explore such huge data to provide useful information in the context of earth observation. To address this issue, a patch based method for mining satellite image time ...

  19. Time resolved single photon imaging in Nanometer Scale CMOS technology

    Richardson, Justin Andrew

    2010-01-01

    Time resolved imaging is concerned with the measurement of photon arrival time. It has a wealth of emerging applications including biomedical uses such as fluorescence lifetime microscopy and positron emission tomography, as well as laser ranging and imaging in three dimensions. The impact of time resolved imaging on human life is significant: it can be used to identify cancerous cells in-vivo, how well new drugs may perform, or to guide a robot around a factory or hospital. ...

  20. Real time neutron radiography using a Lixi neutron imaging device

    A real time neutron radiography system has been developed at the University of Michigan Phoenix Memorial Laboratory (PML) and has recently been used to test the imaging capabilities of a neutron imaging device developed by Lixi, Inc. of Downers Grove, Ill. This device uses an input phosphor that is high in gadolinium to generate a light image which is then sent through an intensifier stage to provide images that can be viewed by eye, video camera, or standard 35 mm camera. It was determined that this device provides images of much higher resolution and sensitivity than those obtained with the imaging system currently being used at PML. Using computerized image enhancement techniques, the images obtained with the Lixi neutron imaging device can then be further enhanced or processed to obtain quantitative information on the object being imaged. (orig.)

  1. Bioluminescent bacteria: lux genes as environmental biosensors Bactrias bioluminescentes: os genes lux como biosensores ambientais

    Vnia da Silva Nunes-Halldorson; Norma Letcia Duran

    2003-01-01

    Bioluminescent bacteria are widespread in natural environments. Over the years, many researchers have been studying the physiology, biochemistry and genetic control of bacterial bioluminescence. These discoveries have revolutionized the area of Environmental Microbiology through the use of luminescent genes as biosensors for environmental studies. This paper will review the chronology of scientific discoveries on bacterial bioluminescence and the current applications of bioluminescence in env...

  2. Real-time evaluation of two light delivery systems for photodynamic disinfection of Candida albicans biofilm in curved root canals.

    Sabino, C P; Garcez, A S; Nez, S C; Ribeiro, M S; Hamblin, M R

    2015-08-01

    Antimicrobial photodynamic therapy (APDT) combined with endodontic treatment has been recognized as an alternative approach to complement conventional root canal disinfection methods on bacterial biofilms. We developed an in vitro model of bioluminescent Candida albicans biofilm inside curved dental root canals and investigated the microbial reduction produced when different light delivery methods are employed. Each light delivery method was evaluated in respect to the light distribution provided inside curved root canals. After conventional endodontic preparation, teeth were sterilized before canals were contaminated by a bioluminescent strain of C. albicans (CEC789). Methylene blue (90?M) was introduced into the canals and then irradiated (??=?660nm, P?=?100mW, beam diameter?=?2mm) with laser tip either in contact with pulp chamber or within the canal using an optical diffuser fiber. Light distribution was evaluated by CCD camera, and microbial reduction was monitored through bioluminescence imaging. Our findings demonstrated that the bioluminescent C. albicans biofilm model had good reproducibility and uniformity. Light distribution in dental tissue was markedly dependent on the light delivery system, and this strategy was directly related to microbial destruction. Both light delivery systems performed significant fungal inactivation. However, when irradiation was performed with optical diffuser fiber, microbial burden reduction was nearly 100 times more effective. Bioluminescence is an interesting real-time analysis to endodontic C. albicans biofilm inactivation. APDT showed to be an effective way to inactivate C. albicans biofilms. Diffuser fibers provided optimized light distribution inside curved root canals and significantly increased APDT efficiency. PMID:25060900

  3. In Vivo Real Time Volumetric Synthetic Aperture Ultrasound Imaging

    Bouzari, Hamed; Rasmussen, Morten Fischer; Brandt, Andreas Hjelm; Stuart, Matthias Bo; Nikolov, Svetoslav; Jensen, Jørgen Arendt

    2015-01-01

    Synthetic aperture (SA) imaging can be used to achieve real-time volumetric ultrasound imaging using 2-D array transducers. The sensitivity of SA imaging is improved by maximizing the acoustic output, but one must consider the limitations of an ultrasound system, both technical and biological. Th...

  4. Real-time video-image analysis

    Eskenazi, R.; Rayfield, M. J.; Yakimovsky, Y.

    1979-01-01

    Digitizer and storage system allow rapid random access to video data by computer. RAPID (random-access picture digitizer) uses two commercially-available, charge-injection, solid-state TV cameras as sensors. It can continuously update its memory with each frame of video signal, or it can hold given frame in memory. In either mode, it generates composite video output signal representing digitized image in memory.

  5. Digital Image Processing: An Overview of Computational Time Requirement.

    Ahaiwe J

    2013-01-01

    Image processing is a growing field covering a wide range of techniques for the manipulation of digital images [1].Many image processing tasks can be characterized as being computationally intensive. One reason for this is the vast amount of data that requires processing, more than seven million pixels per second for typical image sources. To keep up with these data rates and demanding computations in real-time, the processing engine must provide specialized data paths, application-specific o...

  6. Real-Time Augmented Reality for Image-Guided Interventions

    Vogt, Sebastian

    2010-01-01

    The aim of this thesis is to design, develop, and study a new approach to interventional image guidance based on augmented reality visualization – the merging of real and virtual images. This work broadly reviews and categorizes all preliminary augmented reality prototype systems for interventional image guidance. A novel augmented reality setup is introduced and engineered for interventional guidance tasks, integrating pre-operative imaging, namely CT and MRI, as well as real-time ultrasound...

  7. Algorithm for localized adaptive diffuse optical tomography and its application in bioluminescence tomography

    A reconstruction algorithm for diffuse optical tomography based on diffusion theory and finite element method is described. The algorithm reconstructs the optical properties in a permissible domain or region-of-interest to reduce the number of unknowns. The algorithm can be used to reconstruct optical properties for a segmented object (where a CT-scan or MRI is available) or a non-segmented object. For the latter, an adaptive segmentation algorithm merges contiguous regions with similar optical properties thereby reducing the number of unknowns. In calculating the Jacobian matrix the algorithm uses an efficient direct method so the required time is comparable to that needed for a single forward calculation. The reconstructed optical properties using segmented, non-segmented, and adaptively segmented 3D mouse anatomy (MOBY) are used to perform bioluminescence tomography (BLT) for two simulated internal sources. The BLT results suggest that the accuracy of reconstruction of total source power obtained without the segmentation provided by an auxiliary imaging method such as x-ray CT is comparable to that obtained when using perfect segmentation. (paper)

  8. Algorithm for localized adaptive diffuse optical tomography and its application in bioluminescence tomography

    Naser, Mohamed A.; Patterson, Michael S.; Wong, John W.

    2014-04-01

    A reconstruction algorithm for diffuse optical tomography based on diffusion theory and finite element method is described. The algorithm reconstructs the optical properties in a permissible domain or region-of-interest to reduce the number of unknowns. The algorithm can be used to reconstruct optical properties for a segmented object (where a CT-scan or MRI is available) or a non-segmented object. For the latter, an adaptive segmentation algorithm merges contiguous regions with similar optical properties thereby reducing the number of unknowns. In calculating the Jacobian matrix the algorithm uses an efficient direct method so the required time is comparable to that needed for a single forward calculation. The reconstructed optical properties using segmented, non-segmented, and adaptively segmented 3D mouse anatomy (MOBY) are used to perform bioluminescence tomography (BLT) for two simulated internal sources. The BLT results suggest that the accuracy of reconstruction of total source power obtained without the segmentation provided by an auxiliary imaging method such as x-ray CT is comparable to that obtained when using perfect segmentation.

  9. Real-time image quality assessment with mixed Lagrange time delay estimation autoregressive (MLTDEAR) model.

    Sim, K S; Tso, C P; Tan, Y Y; Lim, W K

    2007-06-01

    A proposal to assess the quality of scanning electron microscope images using mixed Lagrange time delay estimation technique is presented. With optimal scanning electron microscope scan rate information, online images can be quantified and improved. The online quality assessment technique is embedded onto a scanning electron microscope frame grabber card for real-time image processing. Different images are captured using scanning electron microscope and a database is built to optimally choose filter parameters. An optimum choice of filter parameters is obtained. With the optimum choice of scan rate, noise can be removed from real-time scanning electron microscope images without causing any sample contamination or increasing scanning time. PMID:17535262

  10. Analysis of time-varying psoriasis lesion image patterns

    Maletti, Gabriela Mariel; Ersbøll, Bjarne Kjær; Nielsen, Allan Aasbjerg; Gomez, David Delgado

    The multivariate alteration detection transform is applied to pairs of within and between time varying registered psoriasis image patterns. Color band contribution to the variates explaining maximal change is analyzed.......The multivariate alteration detection transform is applied to pairs of within and between time varying registered psoriasis image patterns. Color band contribution to the variates explaining maximal change is analyzed....

  11. Study of four regularization methods for the inverse problem in bioluminescence tomography

    He, Xiaowei; Tian, Jie; Wu, Yan; Hou, Yanbin; Ren, Nunu; Peng, Kuan

    2009-02-01

    As a promising tool for in-vivo molecular imaging of small animals, Bioluminescence Tomography (BLT) aims at the quantitative reconstruction of the bioluminescent source distribution from the detected optical signals on the body surface. Mathematically, BLT is a highly ill-posed inverse problem per se. Most existing works are based on Tikhonov regularization in which the selection of the proper regular parameter is quite difficult. In this paper, two direct regularization methods, truncated singular value decomposition (TSVD) and truncated total least squares (TTLS), as well as two iterative regularization methods, conjugate gradient least squares (CGLS) and least squares QR decomposition (LSQR), are applied to the inverse problem in BLT, with the finite element method solving the diffusion equation. In the numerical simulation, a heterogeneous phantom is designed to compare and evaluate the four methods. The results show that all the four methods can reconstruct the position of bioluminescence sources accurately and are more convenient in the determination of regularization parameter than Tikhonov method. In addition, with a priori knowledge of the source permissible region employed in the reconstruction, the iterative methods are faster than the two direct methods. Among the four methods, LSQR performs quite stably when both model noise and measure noise are considered.

  12. An ebCMOS camera system for marine bioluminescence observation: The LuSEApher prototype

    Dominjon, A., E-mail: a.dominjon@ipnl.in2p3.fr [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne F-69622 (France); Ageron, M. [CNRS/IN2P3, Centre de Physique des Particules de Marseille, Marseille, F-13288 (France); Barbier, R. [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne F-69622 (France); Universite de Lyon, Universite Lyon 1, Lyon F-69003 (France); Billault, M.; Brunner, J. [CNRS/IN2P3, Centre de Physique des Particules de Marseille, Marseille, F-13288 (France); Cajgfinger, T. [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne F-69622 (France); Universite de Lyon, Universite Lyon 1, Lyon F-69003 (France); Calabria, P. [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne F-69622 (France); Chabanat, E. [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne F-69622 (France); Universite de Lyon, Universite Lyon 1, Lyon F-69003 (France); Chaize, D.; Doan, Q.T.; Guerin, C.; Houles, J.; Vagneron, L. [CNRS/IN2P3, Institut de Physique Nucleaire de Lyon, Villeurbanne F-69622 (France)

    2012-12-11

    The ebCMOS camera, called LuSEApher, is a marine bioluminescence recorder device adapted to extreme low light level. This prototype is based on the skeleton of the LUSIPHER camera system originally developed for fluorescence imaging. It has been installed at 2500 m depth off the Mediterranean shore on the site of the ANTARES neutrino telescope. The LuSEApher camera is mounted on the Instrumented Interface Module connected to the ANTARES network for environmental science purposes (European Seas Observatory Network). The LuSEApher is a self-triggered photo detection system with photon counting ability. The presentation of the device is given and its performances such as the single photon reconstruction, noise performances and trigger strategy are presented. The first recorded movies of bioluminescence are analyzed. To our knowledge, those types of events have never been obtained with such a sensitivity and such a frame rate. We believe that this camera concept could open a new window on bioluminescence studies in the deep sea.

  13. Spectrally resolved bioluminescence tomography with adaptive finite element analysis: methodology and simulation

    As a molecular imaging technique, bioluminescence tomography (BLT) with its highly sensitive detection and facile operation can significantly reveal molecular and cellular information in vivo at the whole-body small animal level. However, because of complex photon transportation in biological tissue and boundary detection data with high noise, bioluminescent sources in deeper positions generally cannot be localized. In our previous work, we used achromatic or monochromatic measurements and an a priori permissible source region strategy to develop a multilevel adaptive finite-element algorithm. In this paper, we propose a spectrally solved tomographic algorithm with a posteriori permissible source region selection. Multispectral measurements, and anatomical and optical information first deal with the nonuniqueness of BLT and constrain the possible solution of source reconstruction. The use of adaptive mesh refinement and permissible source region based on a posteriori measures not only avoids the dimension disaster arising from the multispectral measured data but also reduces the ill-posedness of BLT and therefore improves the reconstruction quality. Reconsideration of the optimization method and related modifications further enhance reconstruction robustness and efficiency. We also incorporate into the method some improvements for reducing computational burdens. Finally, using a whole-body virtual mouse phantom, we demonstrate the capability of the proposed BLT algorithm to reconstruct accurately bioluminescent sources in deeper positions. In terms of optical property errors and two sources of discernment in deeper positions, this BLT algorithm represents the unique predominance for BLT reconstruction

  14. An ebCMOS camera system for marine bioluminescence observation: The LuSEApher prototype

    The ebCMOS camera, called LuSEApher, is a marine bioluminescence recorder device adapted to extreme low light level. This prototype is based on the skeleton of the LUSIPHER camera system originally developed for fluorescence imaging. It has been installed at 2500 m depth off the Mediterranean shore on the site of the ANTARES neutrino telescope. The LuSEApher camera is mounted on the Instrumented Interface Module connected to the ANTARES network for environmental science purposes (European Seas Observatory Network). The LuSEApher is a self-triggered photo detection system with photon counting ability. The presentation of the device is given and its performances such as the single photon reconstruction, noise performances and trigger strategy are presented. The first recorded movies of bioluminescence are analyzed. To our knowledge, those types of events have never been obtained with such a sensitivity and such a frame rate. We believe that this camera concept could open a new window on bioluminescence studies in the deep sea.

  15. Photo-real rendering of bioluminescence and iridescence in creatures from the abyss

    Prusten, Mark

    2008-08-01

    The generation of photo-real renderings of bioluminescence is developed for creatures from the abyss. Bioluminescence results from a chemical reaction with examples found in deep-sea marine environments including: algae, copepods, jellyfish, squid, and fish. In bioluminescence, the excitation energy is supplied by a chemical reaction, not by a source of light. The greatest transparency window in seawater is in the blue region of the visible spectrum. From small creatures like single-cell algae, to large species of siphonophore Praya dubia (40m), luminescent phenomena can be produced by mechanical excitement from disturbances of objects passing by. Deep sea fish, like the Pacific Black Dragonfish are covered with photophores along the upper and lower surfaces which emits light when disturbed. Other animals like small squids have several different types of light organs oscillating at different rates. Custom shaders and material phenomena incorporate indirect lighting like: global illumination, final gathering, ambient occlusion and subsurface scattering to provide photo real images. Species like the Hydomedusae jellyfish, produce colors that are also generated by iridescence of thin tissues. The modeling and rendering of these tissues requires thin film multilayer stacks. These phenomena are simulated by semi-rigid body dynamics in a procedural animation environment. These techniques have been applied to develop spectral rendering of scenes outside the normal visible window in typical computer animation render engines.

  16. Rapid obtention of stable, bioluminescent tumor cell lines using a tCD2-luciferase chimeric construct

    Gourzones Claire; Wei Ming; Barjon Clément; Gressette Mélanie; Jimenez Anne-Sophie; Busson Pierre

    2011-01-01

    Abstract Background Bioluminescent tumor cell lines are experimental tools of major importance for cancer investigation, especially imaging of tumors in xenografted animals. Stable expression of exogenous luciferase in tumor cells combined to systemic injection of luciferin provides an excellent signal/background ratio for external optical imaging. Therefore, there is a need to rationalize and speed up the production of luciferase-positive tumor cell lines representative of multiple tumor phe...

  17. A new ultrasonic imaging system using time delay spectrometry

    Heyser, R. C.; Le Croissette, D. H.

    1974-01-01

    A new method of forming a visual image by ultrasound is described. A shadowgraphic transmission image similar to an X-ray radiograph is produced by the application of a technique known as Time Delay Spectrometry. The system uses a repetitive frequency sweep with a linear relationship between frequency and time and the transmitting and receiving crystal are scanned in raster fashion about the subject. By electronic processing, an image may be built up which represents the energy transmitted through the specimen with a given time delay. An intensity modulated picture encompassing the full shades-of-gray capability of the recording system can be produced. A second type of image showing transmission time through the specimen may also be formed. Brightness changes in the displayed image in this case correspond to changes in the ultrasonic transmission time through the specimen.

  18. Bioluminescent Monitoring of NIS-mediated 131I Ablative Effects in MCF-7 Xenografts

    Ghosh, Malavika; Gambhir, Sanjiv Sam; Abhijit De; Nowels, Kent; Goris, Michael; Wapnir, Irene

    2006-01-01

    Optical imaging has made it possible to monitor response to anticancer therapies in tumor xenografts. The concept of treating breast cancers with 131I is predicated on the expression of the Na+/I symporter (NIS) in many tumors and uptake of I in some. The pattern of 131I radioablative effects were investigated in an MCF-7 xenograft model dually transfected with firefly luciferase and NIS genes. On Day 16 after tumor cell implantation, 3 mCi of 131I was injected. Bioluminescent imaging using d...

  19. Adaptive Real Time Imaging Synthesis Telescopes

    Wright, Melvyn

    2012-01-01

    The digital revolution is transforming astronomy from a data-starved to a data-submerged science. Instruments such as the Atacama Large Millimeter Array (ALMA), the Large Synoptic Survey Telescope (LSST), and the Square Kilometer Array (SKA) will measure their accumulated data in petabytes. The capacity to produce enormous volumes of data must be matched with the computing power to process that data and produce meaningful results. In addition to handling huge data rates, we need adaptive calibration and beamforming to handle atmospheric fluctuations and radio frequency interference, and to provide a user environment which makes the full power of large telescope arrays accessible to both expert and non-expert users. Delayed calibration and analysis limit the science which can be done. To make the best use of both telescope and human resources we must reduce the burden of data reduction. Our instrumentation comprises of a flexible correlator, beam former and imager with digital signal processing closely coupled...

  20. Real-time extended dynamic range imaging in shearography

    Extended dynamic range (EDR) imaging is a postprocessing technique commonly associated with photography. Multiple images of a scene are recorded by the camera using different shutter settings and are merged into a single higher dynamic range image. Speckle interferometry and holography techniques require a well-modulated intensity signal to extract the phase information, and of these techniques shearography is most sensitive to different object surface reflectivities as it uses self-referencing from a sheared image. In this paper the authors demonstrate real-time EDR imaging in shearography and present experimental results from a difficult surface reflectivity sample: a wooden panel painting containing gold and dark earth color paint

  1. Real-time digital x-ray subtraction imaging

    A method of producing visible difference images derived from an x-ray image of an anatomical subject is described. X-rays are directed through the subject, and the image is converted into television fields comprising trains of analog video signals. The analog signals are converted into digital signals, which are then integrated over a predetermined time corresponding to several television fields. Difference video signals are produced by performing a subtraction between the ongoing video signals and the corresponding integrated signals, and are converted into visible television difference images representing changes in the x-ray image

  2. Biocidal effects of silver and zinc oxide nanoparticles on the bioluminescent bacteria

    Taran, M. V.; Starodub, N. F.; Katsev, A. M.; Guidotti, M.; Khranovskyy, V. D.; Babanin, A. A.; Melnychuk, M. D.

    2013-11-01

    The effect of silver and zinc oxide nanoparticles in combination with alginate on bioluminescent Photobacterium leiognathi Sh1 bacteria was investigated. Silver nanoparticles were found to be more toxic than zinc oxide nanoparticles on bioluminescent bacteria. The nanoparticles and their ions released results in the same effect, however, it was absent in combination with alginate. The effective inhibiting concentration (EC50) for silver nanoparticles was found about 0.3 - 0.4 μg mL-1, which was up to two times larger then for zinc oxide nanoparticles. The absence of sodium chloride in the tested media prevented the formation of colloidal particles of larger size and the effective inhibition concentrations of metal derivatives were lower than in the presence of sodium chloride.

  3. Experimental ultrasound system for real-time synthetic imaging

    Jensen, Jørgen Arendt; Holm, Ole; Jensen, Lars Joost; Bendsen, Henrik; Pedersen, Henrik Møller; Salomonsen, Kent; Hansen, Johnny; Nikolov, Svetoslav

    over 5 to 10 seconds is needed to perform clinical evaluation of synthetic and 3D imaging. This paper describes a real-time system specifically designed for research purposes. The purpose of the system is to make it possible to acquire multi-channel data in real-time from clinical multi...... synthetic aperture imaging, 2D and 3D B-mode and velocity imaging. The system can be used with 128 element transducers and can excite 128 channels and receive and sample data from 64 channels simultaneously at 40 MHz with 12 bits precision. Data can be processed in real time using the system's 80 signal......-element ultrasound transducers, and to enable real-time or near realtime processing of the acquired data. The system will be capable of performing the processing for the currently available imaging methods, and will make it possible to perform initial trials in a clinical environment with new imaging modalities for...

  4. Bioluminescent determination of free fatty acids.

    Kather, H; Wieland, E

    1984-08-01

    A simple, highly specific, and sensitive bioluminescent method for determination of free fatty acids in unextracted plasma or serum has been developed. The method is based on the activation of free fatty acids by acyl-CoA synthetase (EC 6.2.1.3). The pyrophosphate formed is used to phosphorylate fructose 6-phosphate in a reaction catalyzed by the enzyme pyrophosphate-fructose-6-phosphate phosphotransferase (EC 4.1.2.13). The triosephosphates produced from fructose 1,6-bisphosphate by aldolase are oxidized by NAD in the presence of arsenate to 3-phosphoglycerate. The NADH is detected via the bacterial NADH-linked luciferase system. Excellent agreement has been obtained by comparison with accepted methods. In addition, for the determination of serum free fatty acids, the method is particularly applicable for following lipolysis of isolated adipocytes. PMID:6486422

  5. In Vivo Real-Time, Multicolor, Quantum Dot Lymphatic Imaging

    Kosaka, Nobuyuki; Ogawa, Mikako; Sato, Noriko; Choyke, Peter L.; Kobayashi, Hisataka

    2009-01-01

    The lymphatic network is complex and difficult to visualize in real-time in vivo. Moreover, the direction of flow within lymphatic networks is often unpredictable especially in areas with well-developed “watershed” or overlapping lymphatics. Herein, we report a method of in vivo real-time multicolor lymphatic imaging using cadmium–selenium quantum dots (Qdots) with a fluorescence imaging system that enables the simultaneous visualization of up to five distinct lymphatic basins in real-time. F...

  6. Decoding Barcode in Image in Real Time

    Krupa, Martin

    2010-01-01

    The goal of this thesis is to describe barcodes used in real world applications and to create application for real time detecting and decoding of chosen barcodes using computer vision. Normal linear barcode is first introduced, and then two dimensional matrix barcode is described with focus on its origin, usage and structure. Especially the process of localization, encoding and decoding of QR Code, which is chosen for future use in work, is described mainly. Also briefly description of comput...

  7. Real-time digital x-ray subtraction imaging

    The invention provides a method of producing visible difference images derived from an X-ray image of an anatomical subject, comprising the steps of directing X-rays through the anatomical subject for producing an image, converting the image into television fields comprising trains of on-going video signals, digitally storing and integrating the on-going video signals over a time interval corresponding to several successive television fields and thereby producing stored and integrated video signals, recovering the video signals from storage and producing integrated video signals, producing video difference signals by performing a subtraction between the integrated video signals and the on-going video signals outside the time interval, and converting the difference signals into visible television difference images representing on-going changes in the X-ray image

  8. Shedding light on bioluminescence regulation in Vibrio fischeri

    Miyashiro, Tim; Ruby, Edward G

    2012-01-01

    The bioluminescence emitted by the marine bacterium Vibrio fischeri is a particularly striking result of individual microbial cells coordinating a group behavior. The genes responsible for light production are principally regulated by the LuxR-LuxI quorum-sensing system. In addition to LuxR-LuxI, numerous other genetic elements and environmental conditions control bioluminescence production. Efforts to mathematically model the LuxR-LuxI system are providing insight into the dynamics of this a...

  9. Bioluminescence-Sensing Assay for Microbial Growth Recognition

    Heba Ramadan Eed; Abdel-Kader, Nora S.; Mahmoud Helmy El Tahan; Tianhong Dai; Rehab Amin

    2016-01-01

    The conventional methods for microbial viability quantification require cultivation and are laborious. There is consequently a widespread need for cultivation-free methods. The adenosine triphosphate (ATP) bioluminescence-sensing assay is considered an extremely effective biosensor; hence ATP is the energy currency of all living microbes and can be used as a rapid indicator of microbial viability. We developed an ATP bioluminescence-sensing assay to detect microbial viability. A bioluminescen...

  10. Dinoflagellate bioluminescence in response to mechanical stimuli in water flows

    A. S. Cussatlegras; Gal, P

    2005-01-01

    Bioluminescence of plankton organisms induced by water movements has long been observed and is still under investigations because of its great complexity. In particular, the exact mechanism occurring at the level of the cell has not been yet fully understood. This work is devoted to the study of the bioluminescence of the dinoflagellates plankton species Pyrocystis noctiluca in response to mechanical stimuli generated by water flows. Several experiments were performed with different types of ...

  11. Dinoflagellate bioluminescence in response to mechanical stimuli in water flows

    A. S. Cussatlegras; Gal, P.

    2005-01-01

    Bioluminescence of plankton organisms induced by water movements has long been observed and is still under investigations because of its great complexity. In particular, the exact mechanism occurring at the level of the cell has not been yet fully understood. This work is devoted to the study of the bioluminescence of the dinoflagellates plankton species Pyrocystis noctiluca in response to mechanical stimuli generated by water flows. Several experiments were performed with d...

  12. Bioluminescence characteristics of a tropical terrestrial fungus (Basidiomycetes)

    Deheyn, D. D.; Latz, M.I.

    2007-01-01

    Freshly collected samples of luminous mycelium of a terrestrial fungus from Panama were investigated for their bioluminescence characteristics. Taxonomic identification of fungal species could not be determined because of the lack of fruiting bodies. Fluorescence excited by 380 nm illumination had an emission spectrum with a main peak at 480 nm and additional chlorophyll peaks related to the wood substrate. Bioluminescence appeared as a continuous glow that did not show any diel variation. Th...

  13. Real Time Target Tracking in a Phantom Using Ultrasonic Imaging

    Xiao, X.; Corner, G.; Huang, Z.

    In this paper we present a real-time ultrasound image guidance method suitable for tracking the motion of tumors. A 2D ultrasound based motion tracking system was evaluated. A robot was used to control the focused ultrasound and position it at the target that has been segmented from a real-time ultrasound video. Tracking accuracy and precision were investigated using a lesion mimicking phantom. Experiments have been conducted and results show sufficient efficiency of the image guidance algorithm. This work could be developed as the foundation for combining the real time ultrasound imaging tracking and MRI thermometry monitoring non-invasive surgery.

  14. Anisotropy signature in extended images from reverse-time migration

    Sava, Paul

    2012-11-04

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the earth, i.e. at common-image-point gathers (CIPs), carry enough information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. Furthermore, inaccurate anisotropy leaves a distinctive signature in CIPs, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography.

  15. Volumetric Real-Time Imaging Using a CMUT Ring Array

    Choe, Jung Woo; Oralkan, Ömer; Nikoozadeh, Amin; Gencel, Mustafa; Stephens, Douglas N.; O’Donnell, Matthew; Sahn, David J; Khuri-Yakub, Butrus T.

    2012-01-01

    A ring array provides a very suitable geometry for forward-looking volumetric intracardiac and intravascular ultrasound imaging. We fabricated an annular 64-element capacitive micromachined ultrasonic transducer (CMUT) array featuring a 10-MHz operating frequency and a 1.27-mm outer radius. A custom software suite was developed to run on a PC-based imaging system for real-time imaging using this device.

  16. Image reconstruction in PET using time of flight information

    Recent progresses in fast time coincidence technique have permitted the use of time of flight (TOF) information in positron Emission Tomography. We describe the basic concept of positron time of flight imaging and introduce new concepts in order to incorporate the TOF data in the reconstruction process. An algorithm to recover positron activity is then proposed. We describe the image reconstruction in the TTVO1 time of flight camera, the system architecture and the special purpose operators. The time of flight tomography offers large development possibilities and we look forward the new high resolution, high signal-to-noise TOF camera

  17. Photographic documentation in real time radiographic imaging procedures and other inspection procedures using video imaging techniques

    With an automatic daylight video imaging system, based on the use of wet processing type of film, it is possible to produce permanent documents of real time video images with almost the same convenience as video tape recording while maintaining all the advantages of display flexibility and image quality offered by photographic documents

  18. Deep-Sea Bioluminescence Blooms after Dense Water Formation at the Ocean Surface

    Tamburini, Christian; Canals, Miquel; Durrieu de Madron, Xavier; Houpert, Loïc; Lefèvre, Dominique; Martini, Séverine; D'Ortenzio, Fabrizio; Robert, Anne; Testor, Pierre; Aguilar, Juan Antonio; Samarai, Imen Al; Albert, Arnaud; André, Michel; Anghinolfi, Marco; Anton, Gisela; Anvar, Shebli; Ardid, Miguel; Jesus, Ana Carolina Assis; Astraatmadja, Tri L.; Aubert, Jean-Jacques; Baret, Bruny; Basa, Stéphane; Bertin, Vincent; Biagi, Simone; Bigi, Armando; Bigongiari, Ciro; Bogazzi, Claudio; Bou-Cabo, Manuel; Bouhou, Boutayeb; Bouwhuis, Mieke C.; Brunner, Jurgen; Busto, José; Camarena, Francisco; Capone, Antonio; Cârloganu, Christina; Carminati, Giada; Carr, John; Cecchini, Stefano; Charif, Ziad; Charvis, Philippe; Chiarusi, Tommaso; Circella, Marco; Coniglione, Rosa; Costantini, Heide; Coyle, Paschal; Curtil, Christian; Decowski, Patrick; Dekeyser, Ivan; Deschamps, Anne; Donzaud, Corinne; Dornic, Damien; Dorosti, Hasankiadeh Q.; Drouhin, Doriane; Eberl, Thomas; Emanuele, Umberto; Ernenwein, Jean-Pierre; Escoffier, Stéphanie; Fermani, Paolo; Ferri, Marcelino; Flaminio, Vincenzo; Folger, Florian; Fritsch, Ulf; Fuda, Jean-Luc; Galatà, Salvatore; Gay, Pascal; Giacomelli, Giorgio; Giordano, Valentina; Gómez-González, Juan-Pablo; Graf, Kay; Guillard, Goulven; Halladjian, Garadeb; Hallewell, Gregory; van Haren, Hans; Hartman, Joris; Heijboer, Aart J.; Hello, Yann; Hernández-Rey, Juan Jose; Herold, Bjoern; Hößl, Jurgen; Hsu, Ching-Cheng; de Jong, Marteen; Kadler, Matthias; Kalekin, Oleg; Kappes, Alexander; Katz, Uli; Kavatsyuk, Oksana; Kooijman, Paul; Kopper, Claudio; Kouchner, Antoine; Kreykenbohm, Ingo; Kulikovskiy, Vladimir; Lahmann, Robert; Lamare, Patrick; Larosa, Giuseppina; Lattuada, Dario; Lim, Gordon; Presti, Domenico Lo; Loehner, Herbert; Loucatos, Sotiris; Mangano, Salvatore; Marcelin, Michel; Margiotta, Annarita; Martinez-Mora, Juan Antonio; Meli, Athina; Montaruli, Teresa; Motz, Holger; Neff, Max; Nezri, Emma nuel; Palioselitis, Dimitris; Păvălaş, Gabriela E.; Payet, Kevin; Payre, Patrice; Petrovic, Jelena; Piattelli, Paolo; Picot-Clemente, Nicolas; Popa, Vlad; Pradier, Thierry; Presani, Eleonora; Racca, Chantal; Reed, Corey; Riccobene, Giorgio; Richardt, Carsten; Richter, Roland; Rivière, Colas; Roensch, Kathrin; Rostovtsev, Andrei; Ruiz-Rivas, Joaquin; Rujoiu, Marius; Russo, Valerio G.; Salesa, Francisco; Sánchez-Losa, Augustin; Sapienza, Piera; Schöck, Friederike; Schuller, Jean-Pierre; Schussler, Fabian; Shanidze, Rezo; Simeone, Francesco; Spies, Andreas; Spurio, Maurizio; Steijger, Jos J. M.; Stolarczyk, Thierry; Taiuti, Mauro G. F.; Toscano, Simona; Vallage, Bertrand; Van Elewyck, Véronique; Vannoni, Giulia; Vecchi, Manuela; Vernin, Pascal; Wijnker, Guus; Wilms, Jorn; de Wolf, Els; Yepes, Harold; Zaborov, Dmitry; De Dios Zornoza, Juan; Zúñiga, Juan

    2013-01-01

    The deep ocean is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep waters. Such changes are triggered by the winter cooling and evaporation experienced by the upper ocean layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense water through a process known as “open-sea convection”. It episodically renews the deep water of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep open-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense water formation events are likely to decline under global warming scenarios enhancing ocean stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts. PMID:23874425

  19. Real time K-edge subtraction x-ray imaging

    This paper describes an x-ray K-edge subtraction television system for noninvasive angiography utilizing synchrotron radiation. The phantom, including contrast material (iodine), is irradiated by monochromatized dual-energy x-ray flux, alternately, using a high speed monochromator. The monochromator consists of a silicon crystal plate vibrating at 15 Hz so that the phantom is irradiated by the x-ray flux of 150 eV above and below the K-edge photon energy of iodine, 15 times per second. As an x-ray detector, TV cameras optically coupled to an x-ray image intensifier are used and the video signal is processed to display the subtraction image of pairs of successive images in real time. This system was fully implemented and moving phantoms were examined. Both the time interval between the energy change and the exposure time of each image has been shortened to 2 ms

  20. Real-time movie image enhancement in NMR

    Clinical NMR motion picture (movie) images can now be produced routinely in real-time by ultra-high-speed echo-planar imaging (EPI). The single-shot image quality depends on both pixel resolution and signal-to-noise ratio (S/N), both factors being intertradeable. If image S/N is sacrificed rather than resolution, it is shown that S/N may be greatly enhanced subsequently without vitiating spatial resolution or foregoing real motional effects when the object motion is periodic. This is achieved by a Fourier filtering process. Experimental results are presented which demonstrate the technique for a normal functioning heart. (author)

  1. Real time image segmentation using an adaptive thresholding approach

    Arques Corrales, Pilar; Aznar Gregori, Fidel; Pujol López, Mar; Rizo Aldeguer, Ramón

    2006-01-01

    The aim of image segmentation is the partition of the image in homogeneous regions. In this paper we propose an approximation based on Markov Random Fields (MRF) able to perform correct segmentation in real time using colour information. In a first approximation a simulated annealing approach is used to obtain the optimal segmentation. This segmentation will be improved using an adaptive threshold algorithm, to achieve real time. The experiment results using the proposed segmentation pr...

  2. Dynamics of embryonic pancreas development using real-time imaging

    Puri, Sapna; Hebrok, Matthias

    2007-01-01

    Current knowledge about developmental processes in complex organisms has relied almost exclusively on analyses of fixed specimens. However, organ growth is highly dynamic, and visualization of such dynamic processes, e.g. real-time tracking of cell movement and tissue morphogenesis, is becoming increasingly important. Here, we use live imaging to investigate expansion of the embryonic pancreatic epithelium in mouse. Using time-lapse imaging of tissue explants in culture, fluorescently labeled...

  3. Tomographic time-of-flight optical imaging device.

    Benaron, D A; Ho, D C; Spilman, S; Van Houten, J P; Stevenson, D K

    1994-01-01

    Time-resolved optical imaging has been used to image phantoms, animals, and humans, and offers the potential for the production of functional images of human tissues, such as the oxygenation of brain during stroke. We had previously reported a transmission scanner, and now give an early report on conversion to a rotational tomographic scanner with a non-parallel ray geometry similar to early CAT scanners. Initial scans show that 1) spatial imaging in turbid media using time-of-flight measurements, non-recursive algorithms, and standard tomographic geometry is possible, 2) separation of absorbance and scattering as an image is attainable, a key step in performing spatially-resolved chemometric analysis, 3) imaging of multiple objects buried within scattering material is feasible, demonstrating that equations derived for homogeneous media can be applied in at least some cases to inhomogeneous media such as tissue-like phantoms, and 4) imaging of brain pathology produces recognizable images with sufficient resolution for diagnostic decisions. We conclude that optical tomography is feasible for clinical use and that conversion of the present mechanically scanning device to a clinical scanner should be possible with retention of the current processing algorithms. Such a clinical scanner should ultimately be able to generate images in a few minutes with centimeter resolution at the center of living human brain. PMID:7597945

  4. Anisotropy signature in reverse-time migration extended images

    Sava, Paul C.

    2014-11-04

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at common-image-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a challenge. Extended common-image-point gathers are cheap to evaluate since they sample the image at sparse locations indicated by the presence of strong reflectors. Such gathers are also sensitive to velocity error that manifests itself through moveout as a function of space and time lags. Furthermore, inaccurate anisotropy leaves a distinctive signature in common-image-point gathers, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography. It specifically admits a V-shaped residual moveout with the slope of the "V" flanks depending on the anisotropic parameter η regardless of the complexity of the velocity model. It reflects the fourth-order nature of the anisotropy influence on moveout as it manifests itself in this distinct signature in extended images after handling the velocity properly in the imaging process. Synthetic and real data observations support this assertion.

  5. Real time MRI-ultrasound image guided stereotactic prostate biopsy.

    Kaplan, Irving; Oldenburg, Nicklas E; Meskell, Paul; Blake, Michael; Church, Paul; Holupka, Edward J

    2002-04-01

    To report a technique for target directed transperineal ultrasound guided biopsy using high resolution endorectal MRI images Ultrasound fusion. Two patients presented after external beam irradiation for prostate cancer with a rising PSA. An Endorectal MRI using a 1.5 Tesla scanner was obtained. Subsequently a Transrectal Ultrasound guided biopsy was performed. The Ultrasound probe was fixed to a stepper-stabilizer to provide a reference coordinate system for stereotaxic needle biopsy needle placement. The MRI image set was fused to the Ultrasound images in real time. Abnormal areas determined in the MR images were targeted for biopsy. Recurrent prostate carcinoma was detected pathologically in 3 of 4 stereotactic biopsies. Abnormal areas suspicious for cancer detected on T1 weighted images obtained in a strong field Endorectal MRI scan can be targeted for stereotactic biopsy using Transrectal Ultrasound. This image guide technique may be very useful in directing biopsies. PMID:12117612

  6. Multimodal MR imaging of acute and subacute experimental traumatic brain injury: Time course and correlation with cerebral energy metabolites

    Traumatic brain injury (TBI) is one of the leading causes of death and permanent disability world-wide. The predominant cause of death after TBI is brain edema which can be quantified by non-invasive diffusion-weighted magnetic resonance imaging (DWI). To provide a better understanding of the early onset, time course, spatial development, and type of brain edema after TBI and to correlate MRI data and the cerebral energy state reflected by the metabolite adenosine triphosphate (ATP). The spontaneous development of lateral fluid percussion-induced TBI was investigated in the acute (6 h), subacute (48 h), and chronic (7 days) phase in rats by MRI of quantitative T2 and apparent diffusion coefficient (ADC) mapping as well as perfusion was combined with ATP-specific bioluminescence imaging and histology. An induced TBI led to moderate to mild brain damages, reflected by transient, pronounced development of vasogenic edema and perfusion reduction. Heterogeneous ADC patterns indicated a parallel, but mixed expression of vasogenic and cytotoxic edema. Cortical ATP levels were reduced in the acute and subacute phase by 13% and 27%, respectively, but were completely normalized at 7 days after injury. The partial ATP reduction was interpreted to be partially caused by a loss of neurons in parallel with transient dilution of the regional ATP concentration by pronounced vasogenic edema. The normalization of energy metabolism after 7 days was likely due to infiltrating glia and not to recovery. The MRI combined with metabolite measurement further improves the understanding and evaluation of brain damages after TBI

  7. Time-gated optical imaging through turbid media using stimulated Raman scattering: Studies on image contrast

    K Divakar Rao; H S Patel; B Jain; P K Gupta

    2005-02-01

    In this paper, we report the development of experimental set-up for timegated optical imaging through turbid media using stimulated Raman scattering. Our studies on the contrast of time-gated images show that for a given optical thickness, the image contrast is better for sample with lower scattering coefficient and higher physical thickness, and that the contrast improves with decreasing value of anisotropy parameters of the scatterers. These results are consistent with time-resolved Monte Carlo simulations.

  8. Implied Movement in Static Images Reveals Biological Timing Processing

    Francisco Carlos Nather

    2015-08-01

    Full Text Available Visual perception is adapted toward a better understanding of our own movements than those of non-conspecifics. The present study determined whether time perception is affected by pictures of different species by considering the evolutionary scale. Static (“S” and implied movement (“M” images of a dog, cheetah, chimpanzee, and man were presented to undergraduate students. S and M images of the same species were presented in random order or one after the other (S-M or M-S for two groups of participants. Movement, Velocity, and Arousal semantic scales were used to characterize some properties of the images. Implied movement affected time perception, in which M images were overestimated. The results are discussed in terms of visual motion perception related to biological timing processing that could be established early in terms of the adaptation of humankind to the environment.

  9. Towards real-time medical diagnostics using hyperspectral imaging technology

    Bjorgan, Asgeir; Randeberg, Lise L.

    2015-07-01

    Hyperspectral imaging provides non-contact, high resolution spectral images which has a substantial diagnostic potential. This can be used for e.g. diagnosis and early detection of arthritis in finger joints. Processing speed is currently a limitation for clinical use of the technique. A real-time system for analysis and visualization using GPU processing and threaded CPU processing is presented. Images showing blood oxygenation, blood volume fraction and vessel enhanced images are among the data calculated in real-time. This study shows the potential of real-time processing in this context. A combination of the processing modules will be used in detection of arthritic finger joints from hyperspectral reflectance and transmittance data.

  10. Real-time transfer and display of radiography image

    The information process network of cobalt-60 container inspection system is a local area network based on PC. The system requires reliable transfer of radiography image between collection station and process station and the real-time display of radiography image on process station. Due to the very high data acquisition rate, in order to realize the real-time transfer and display of radiography image, 100 M Ethernet technology and network process communication technology are adopted in the system. Windows Sockets is the most common process communication technology up to now. Several kinds of process communication way under Windows Sockets technology are compared and tested. Finally the author realized 1 Mbyte/s' inerrant image transfer and real-time display with blocked datagram transfer technology

  11. Transmission mode time-reversal super-resolution imaging

    Lehman, Sean K.; Devaney, Anthony J.

    2003-05-01

    The theory of time-reversal super-resolution imaging of point targets embedded in a reciprocal background medium [A. J. Devaney, ``Super-resolution imaging using time-reversal and MUSIC,'' J. Acoust. Soc. Am. (to be published)] is generalized to the case where the transmitter and receiver sensor arrays need not be coincident and for cases where the background medium can be nonreciprocal. The new theory developed herein is based on the singular value decomposition of the generalized multistatic data matrix of the sensor system rather than the standard eigenvector/eigenvalue decomposition of the time-reversal matrix as was employed in the above-mentioned work and other treatments of time-reversal imaging [Prada, Thomas, and Fink, ``The iterative time reversal process: Analysis of the convergence,'' J. Acoust. Soc. Am. 97, 62 (1995); Prada et al., ``Decomposition of the time reversal operator: Detection and selective focusing on two scatterers,'' J. Acoust. Soc. Am. 99, 2067 (1996)]. A generalized multiple signal classification (MUSIC) algorithm is derived that allows super-resolution imaging of both well-resolved and non-well-resolved point targets from arbitrary sensor array geometries. MUSIC exploits the orthogonal nature of the scatterer and noise subspaces defined by the singular vectors of the multistatic data matrix to form scatterer images. The time-reversal/MUSIC algorithm is tested and validated in two computer simulations of offset vertical seismic profiling where the sensor sources are aligned along the earth's surface and the receiver array is aligned along a subsurface borehole. All results demonstrate the high contrast, high resolution imaging capabilities of this new algorithm combination when compared with ``classical'' backpropagation or field focusing. Above and beyond the application of seismo-acoustic imaging, the time-reversal super-resolution theory has applications in ocean acoustics for target location, and ultrasonic nondestructive evaluation of parts.

  12. Time-resolved multispectral imaging of combustion reaction

    Huot, Alexandrine; Gagnon, Marc-André; Jahjah, Karl-Alexandre; Tremblay, Pierre; Savary, Simon; Farley, Vincent; Lagueux, Philippe; Guyot, Éric; Chamberland, Martin; Marcotte, Fréderick

    2015-05-01

    Thermal infrared imaging is a field of science that evolves rapidly. Scientists have used for years the simplest tool: thermal broadband cameras. This allows to perform target characterization in both the longwave (LWIR) and midwave (MWIR) infrared spectral range. Infrared thermal imaging is used for a wide range of applications, especially in the combustion domain. For example, it can be used to follow combustion reactions, in order to characterize the injection and the ignition in a combustion chamber or even to observe gases produced by a flare or smokestack. Most combustion gases such as carbon dioxide (CO2) selectively absorb/emit infrared radiation at discrete energies, i.e. over a very narrow spectral range. Therefore, temperatures derived from broadband imaging are not reliable without prior knowledge about spectral emissivity. This information is not directly available from broadband images. However, spectral information is available using spectral filters. In this work, combustion analysis was carried out using Telops MS-IR MW camera which allows multispectral imaging at a high frame rate. A motorized filter wheel allowing synchronized acquisitions on eight (8) different channels was used to provide time-resolved multispectral imaging of combustion products of a candle in which black powder has been burnt to create a burst. It was then possible to estimate the temperature by modeling spectral profile derived from information obtained with the different spectral filters. Comparison with temperatures obtained using conventional broadband imaging illustrates the benefits of time-resolved multispectral imaging for the characterization of combustion processes.

  13. Time-resolved multispectral imaging of combustion reactions

    Huot, Alexandrine; Gagnon, Marc-André; Jahjah, Karl-Alexandre; Tremblay, Pierre; Savary, Simon; Farley, Vincent; Lagueux, Philippe; Guyot, Éric; Chamberland, Martin; Marcotte, Frédérick

    2015-10-01

    Thermal infrared imaging is a field of science that evolves rapidly. Scientists have used for years the simplest tool: thermal broadband cameras. These allow to perform target characterization in both the longwave (LWIR) and midwave (MWIR) infrared spectral range. Infrared thermal imaging is used for a wide range of applications, especially in the combustion domain. For example, it can be used to follow combustion reactions, in order to characterize the injection and the ignition in a combustion chamber or even to observe gases produced by a flare or smokestack. Most combustion gases, such as carbon dioxide (CO2), selectively absorb/emit infrared radiation at discrete energies, i.e. over a very narrow spectral range. Therefore, temperatures derived from broadband imaging are not reliable without prior knowledge of spectral emissivity. This information is not directly available from broadband images. However, spectral information is available using spectral filters. In this work, combustion analysis was carried out using a Telops MS-IR MW camera, which allows multispectral imaging at a high frame rate. A motorized filter wheel allowing synchronized acquisitions on eight (8) different channels was used to provide time-resolved multispectral imaging of combustion products of a candle in which black powder has been burnt to create a burst. It was then possible to estimate the temperature by modeling spectral profiles derived from information obtained with the different spectral filters. Comparison with temperatures obtained using conventional broadband imaging illustrates the benefits of time-resolved multispectral imaging for the characterization of combustion processes.

  14. Bioluminescence-mediated longitudinal monitoring of adipose-derived stem cells in a large mammal ex vivo organ culture

    Mirte Peeters; Sjoerd van Rijn; Vergroesen, Pieter-Paul A.; Paul, Cornelis P. L.; Noske, David P.; Peter Vandertop, W.; Thomas Wurdinger; Helder, Marco N

    2015-01-01

    Recently, ex vivo three-dimensional organ culture systems have emerged to study the physiology and pathophysiology of human organs. These systems also have potential as a translational tool in tissue engineering; however, this potential is limited by our ability to longitudinally monitor the fate and action of cells used in regenerative therapies. Therefore, we investigated luciferase-mediated bioluminescence imaging (BLI) as a non-invasive technique to continuously monitor cellular behavior ...

  15. Dual monitoring using {sup 124}I-FIAU and bioluminescence for HSV1-tk suicide gene therapy

    Lee, T. S.; Kim, J. H.; Kwon, H. C. [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)] (and others)

    2007-07-01

    Herpes simplex virus type I thymidine kinase (HSV-tk) is the most common reporter gene and is used in cancer gene therapy with a prodrug nucleoside analog, ganciclovir (GCV). The aim of this study is to evaluate therapeutic efficacy of suicide gene therapy with 2'-fluoro-2'-deoxy-1-D-arabinofuranosyl-5-[{sup 124}I] iodouracil ({sup 124}I - FIAU) and bioluminescence in retrovirally HSV -tk and firefly luciferase transduced hepatoma model. The HSV -tk and firefly luciferase (Luc) was retrovirally transduced and expressed in MCA rat Morris hepatoma cells. Nude mice with subcutaneous tumors, MCA and MCA-TK-Luc, were subjected to GCV treatment (50mg/Kg/d intraperitoneally) for 5 day. PET imaging and biodistribution with ({sup 124}I-FIAU) were performed at before and after initiation of therapy with GCV. Bioluminescent signal was also measured during GCV treatment. Before GCV treatment, no significant difference in tumor volume was found in tumors between MCA and MCA-TK-Luc. After GCV treatment, tumor volume of MCA-TK-Luc markedly reduced compared to that of MCA. In biodistribution study, {sup 124}I-FIAU uptake after GCV therapy significantly decreased compared with pretreatment levels (34.8 13.67 %ID/g vs 7.6 2.59 %ID/g) and bioluminescent signal was also significantly decreased compared with pretreatment levels. In small animal PET imaging, {sup 124}I-FIAU selectively localized in HSV -tk expressing tumor and the therapeutic efficacy of GCV treatment was evaluated by {sup 124}I-FIAU PET imaging. {sup 124}I-FIAU PET and bioluminescence imaging in HSV-tk suicide gene therapy were effective to evaluate the therapeutic response. {sup 124}I-FIAU may serve as an efficient and selective agent for monitoring of transduced HSV1-tk gene expression in vivo in clinical trials.

  16. Real-time time-domain fluorescence lifetime imaging including single-shot acquisition with a segmented optical image intensifier

    High-speed (video-rate) fluorescence lifetime imaging (FLIM) is reported using two different time-domain approaches based on gated optical image intensifier technology. The first approach utilizes a rapidly switchable variable delay generator with sequential image acquisition, while the second employs a novel segmented gated optical imager to acquire lifetime maps in a single shot. Lifetimes are fitted using both a non-linear least-squares fit analysis and the rapid lifetime determination method. Monte Carlo simulations were used to optimize the acquisition parameters and a comparison between theory and experiment is presented. The importance of single-shot imaging to minimize the deleterious impact of sample movements is highlighted. Real-time FLIM movies of multi-well plate samples and tissue autofluorescence are presented

  17. [A technology of real-time image compression for convex grating imaging spectrometer].

    Liu, Yang-chuan; Bayanheshig; Cui, Ji-cheng; Tang, Yu-guo

    2012-04-01

    The huge amount of convex grating imaging spectrometer image data brings much pressure to data transmission and storage, so the image must be compressed in real time. Firstly, the image characteristics were analyzed according to the imaging principle, and the compression approach to removing spatial correlation and spectral correlation was achieved; Secondly, the compression algorithms were analyzed and the 3-D compression scheme of one-order linear compression in spectral dimension and JPEG2000 compression in spatial dimension was proposed. Finally, a real-time compression system based on FPGA and ADV212 was designed, in which FPGA was used for logic control and implementation of prediction algorithm, and ADV212 was used for JPEG2000 compression. The analysis result shows that the system has the ability of lossless and lossy compression, enabling real-time image compression. PMID:22715801

  18. Image-Based Learning Approach Applied to Time Series Forecasting

    J. C. Chimal-Eguía

    2012-06-01

    Full Text Available In this paper, a new learning approach based on time-series image information is presented. In order to implementthis new learning technique, a novel time-series input data representation is also defined. This input datarepresentation is based on information obtained by image axis division into boxes. The difference between this newinput data representation and the classical is that this technique is not time-dependent. This new information isimplemented in the new Image-Based Learning Approach (IBLA and by means of a probabilistic mechanism thislearning technique is applied to the interesting problem of time series forecasting. The experimental results indicatethat by using the methodology proposed in this article, it is possible to obtain better results than with the classicaltechniques such as artificial neuronal networks and support vector machines.

  19. Application of image processing for terahertz time domain spectroscopy imaging quantitative detection

    Li, Li-juan; Wang, Sheng; Ren, Jiao-jiao; Zhou, Ming-xing; Zhao, Duo

    2015-03-01

    According to nondestructive testing principle for the terahertz time domain spectroscopy Imaging, using digital image processing techniques, through Terahertz time-domain spectroscopy system collected images and two-dimensional datas and using a range of processing methods, including selecting regions of interest, contrast enhancement, edge detection, and defects being detected. In the paper, Matlab programming is been use to defect recognition of Terahertz, by figuring out the pixels to determine defects defect area and border length, roundness, diameter size. Through the experiment of the qualitative analysis and quantitative calculation of Matlab image processing, this method of detection of defects of geometric dimension of the sample to get a better result.

  20. Bioluminescent assays for high-throughput screening.

    Fan, Frank; Wood, Keith V

    2007-02-01

    In the development of high throughput screening (HTS) as a central paradigm of drug discovery, fluorescence has generally been adopted as the favored methodology. Nevertheless, luminescence has maintained a prominent position among certain assay formats, most notably genetic reporters. Recently, there has been growing partiality for luminescent assays across a wider range of applications due to their sensitivity, broad linearity, and robustness to library compounds and complex biological samples. This trend has been fostered by the development of several new assay designs for diverse targets such as kinases, cytochrome p450s, proteases, apoptosis, and cytotoxicity. This review addresses recent progress made in the use of bioluminescent assays for HTS, highlighting new detection capabilities brought about by engineering luciferase genes, enzymes, and substrates. In genetic reporter applications, modifications to the luciferase genes have improved assay sensitivity by substantially increasing expression efficiency and enhanced response dynamics by reducing expression lifetime. The performance of assays based on detection of ATP and luciferin has been enhanced by modifications to the luciferase enzyme that increase its chemical and physical stability. Detection of ATP allows rapid analysis of cell metabolism and enzymatic processes coupled to ATP metabolism. Because luciferins are not naturally associated with mammalian physiology, assays for luciferin detection utilize synthetic derivatives designed to yield luminescence only when coupled with specific target enzymes. Finally, new methods for modulating the specific activity of luciferases are leading to the development of intracellular biosensors for dynamic detection of physiological processes. PMID:17355205

  1. Dynamic image reconstruction in time-resolved diffuse optical tomography

    Powell, Samuel; Cooper, Robert J.; Hebden, Jeremy C.; Arridge, Simon R.

    2015-03-01

    Optical imaging techniques provide a means of monitoring haemodynamics and tissue oxygenation by virtue of the differing absorption spectra of relevant endogenous chromophores. Whilst time-domain diffuse optical tomography offers sufficient sensitivity to produce full three dimensional images of such properties through the entire infant brain, standard approaches to the imaging protocol and reconstruction methods limit the temporal resolution which can be achieved without an unacceptable degradation in the image quality. In this work we employ spatio-temporal regularisation by means of a variational form Kalman filter to achieve significantly improved temporal resolution whilst maintaining image quality. We demonstrate this approach in a dynamic phantom study where we successfully track moving absorbing and scattering targets using the MONSTIR II instrument developed at University College London.

  2. Precision cosmology with time delay lenses: high resolution imaging requirements

    Meng, Xiao-Lei; Agnello, Adriano; Auger, Matthew W; Liao, Kai; Marshall, Philip J

    2015-01-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as "Einstein Rings" in high resolution images. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope $\\gamma'$ of the...

  3. Mathematical methods in time series analysis and digital image processing

    Kurths, J; Maass, P; Timmer, J

    2008-01-01

    The aim of this volume is to bring together research directions in theoretical signal and imaging processing developed rather independently in electrical engineering, theoretical physics, mathematics and the computer sciences. In particular, mathematically justified algorithms and methods, the mathematical analysis of these algorithms, and methods as well as the investigation of connections between methods from time series analysis and image processing are reviewed. An interdisciplinary comparison of these methods, drawing upon common sets of test problems from medicine and geophysical/enviromental sciences, is also addressed. This volume coherently summarizes work carried out in the field of theoretical signal and image processing. It focuses on non-linear and non-parametric models for time series as well as on adaptive methods in image processing.

  4. Real-time terahertz imaging for art conservation science

    Fukunaga, K.; Sekine, N.; Hosako, I.; Oda, N.; Yoneyama, H.; Sudou, T.

    2008-08-01

    A new real-time terahertz imaging system has been developed by using a quantum cascade laser source and a microbolometer focal plane detector array. The application to non-invasive analyses of cultural heritage is demonstrated with an oil paint specimen. The experimental results suggested that the terahertz imaging system can identify materials based on a spectral database with a spatial resolution of about 300 μm. The transmission imaging indicated the difference between natural and artificial ultramarine pigments. Since the size of the system is similar to a common portable infrared camera, it can be used at the place where the object is located, such as museums, and can contribute to conservation activities, such as drying process monitoring. This real-time, small, non-invasive terahertz imaging system can be used in various fundamental research fields and practical industries.

  5. Real-time oriented image analysis in microcirculatory research

    Pries, Axel R.; Eriksson, S. E.; Jepsen, H.

    1990-11-01

    A digital video image analysis system is presented which consists of a personal computer equipped with a real-time video digitizer and a graphic tablet controlled by a modular set of programs aimed at performing a number of real-time oriented measuring tasks in microcirculatory research. Such tasks comprize the continuous recording of vessel diameters flow velocities or light intensity profiles from video recordings obtained during intravital microscopy of the terminal vascular bed either in research animals or in human beings. Two outstanding features of the presented systems are (A) the spatial correlation module for velocity measurement and (B) the automatic background movement correction. A: The spatial correlation velocity measurement module combined with an asymmetric illumination or gating process for image generation allows measurement of flow velocities from video microscopic images up to 20 mm/sec. This is about 10 to 20 times faster than the maximum. velocities which can be measured using conventional video based techniques. B: The automatic background movement correction is designed to track translational movements of background image structures in a reference window in real time (with respect to the video system). The translational vector of the image background is then used to adjust the position of the individual measuring lines or windows used in the different application modules to their original position relative to the tissue structures which are investigated. Such an automatic real-time tracking system isvery often a

  6. Investigations on time stability of passive THz imaging

    Kowalski, Marcin; Palka, Norbert; Zyczkowski, Marek; Szustakowski, Mieczyslaw

    2014-10-01

    Terahertz radiation is within the frequency range from 100 GHz to 10THz. This radiation has specific characteristics in terms of imaging. The radiation is harmless to the human body because the energy transferred by electromagnetic waves in this range of frequencies are very small thus there is no ionization of matter. The development of imaging devices and exploration of new spectral bands is a chance to introduce new equipment for assuring public safety. It has been proved that objects hidden under clothing can be detected and visualized using terahertz (THz) cameras. However, passive THz cameras still offer too low image resolution for objects recognition. In order to determine the properties of terahertz imaging for detection of hidden objects several aspects need to be considered. Taking into account the fact that the image captured by the terahertz camera reflects the spatial distribution of the relative temperature of the observed objects, the effect of the measurement time on the imaging capabilities should be examined. A very important aspect is the influence of the type (material composition) of coating material, as well as the type of an object hidden under clothing (size and material). The purpose of the studies is to investigate the time stability of passive THz imaging on 250 GHz for detection of concealed objects. In the article, we present the measurement setup, the measurement methodology as well as the initial results of measurements with various types of clothing and test objects.

  7. Time-Reversal Acoustics and Maximum-Entropy Imaging

    Berryman, J G

    2001-08-22

    Target location is a common problem in acoustical imaging using either passive or active data inversion. Time-reversal methods in acoustics have the important characteristic that they provide a means of determining the eigenfunctions and eigenvalues of the scattering operator for either of these problems. Each eigenfunction may often be approximately associated with an individual scatterer. The resulting decoupling of the scattered field from a collection of targets is a very useful aid to localizing the targets, and suggests a number of imaging and localization algorithms. Two of these are linear subspace methods and maximum-entropy imaging.

  8. A bioluminescent assay for the sensitive detection of proteases.

    Leippe, Donna M; Nguyen, Duy; Zhou, Min; Good, Troy; Kirkland, Thomas A; Scurria, Mike; Bernad, Laurent; Ugo, Tim; Vidugiriene, Jolanta; Cali, James J; Klaubert, Dieter H; O'Brien, Martha A

    2011-08-01

    A bioluminescent general protease assay was developed using a combination of five luminogenic peptide substrates. The peptide-conjugated luciferin substrates were combined with luciferase to form a homogeneous, coupled-enzyme assay. This single-reagent format minimized backgrounds, gave stable signals, and reached peak sensitivity within 30 min. The bioluminescent assay was used to detect multiple proteases representing serine, cysteine, and metalloproteinase classes. The range of proteases detected was broader and the sensitivity greater, when compared with a standard fluorescent assay based on cleavage of the whole protein substrate casein. Fifteen of twenty proteases tested had signal-to-background ratios >10 with the bioluminescent method, compared with only seven proteases with the fluorescent approach. The bioluminescent assay also achieved lower detection limits (≤100 pg) than fluorescent methods. During protein purification processes, especially for therapeutic proteins, even trace levels of contamination can impact the protein's stability and activity. This sensitive, bioluminescent, protease assay should be useful for applications in which contaminating proteases are detrimental and protein purity is essential. PMID:21806554

  9. Time-Frequency and Time-Scale-Based Fragile Watermarking Methods for Image Authentication

    Sattar Farook

    2010-01-01

    Full Text Available Two fragile image watermarking methods are proposed for image authentication. The first method is based on time-frequency analysis and the second one is based on time-scale analysis. For the first method, the watermark is chosen as an arbitrary nonstationary signal with a particular signature in the time-frequency plane. Experimental results show that this technique is very sensitive to many attacks such as cropping, scaling, translation, JPEG compression, and rotation, making it very effective in image authentication. For the second method, based on a wavelet-domain multiresolution analysis, quantization index modulation (QIM embedding scheme and arbitrary frequency-modulated (FM chirp watermarks are used in the implementation. In this blind technique, the original watermark is needed neither for the content integrity verification of the original image nor for the content quality assessment of the distorted image.

  10. Modelling dinoflagellates as an approach to the seasonal forecasting of bioluminescence in the North Atlantic

    Marcinko, Charlotte L.J.; Martin, Adrian P.; Allen, John T.

    2014-01-01

    Bioluminescence within ocean surface waters is of significant interest because it can enhance the study of subsurface movement and organisms. Little is known about how bioluminescence potential (BPOT) varies spatially and temporally in the open ocean. However, light emitted from dinoflagellates often dominates the stimulated bioluminescence field. As a first step towards forecasting surface ocean bioluminescence in the open ocean, a simple ecological model is developed which simulates seasona...

  11. Vegetable seed radiosensitivity and kinetic analysis of super-weak bioluminescence

    Bioluminescence of several vegetable seeds induced by γ-rays was studied. The results show that positive relation exists between seeds bioluminescence and irradiation dose, which fits with equation Y=Y0eKD. The higher the K value is, the more intense the bioluminescence induced by γ-rays is. Significant differences among K values were found with different varieties. The bioluminescence and exterior measurement value of seed radiosensitivity showed good consistency

  12. Visualizing real-time influenza virus infection, transmission and protection in ferrets

    Karlsson, Erik A.; Meliopoulos, Victoria A.; Savage, Chandra; Livingston, Brandi; Mehle, Andrew; SCHULTZ-CHERRY, STACEY

    2015-01-01

    Influenza transmission efficiency in ferrets is vital for risk-assessment studies. However, the inability to monitor viral infection and transmission dynamics in real time only provides a glimpse into transmissibility. Here we exploit a replication-competent influenza reporter virus to investigate dynamics of infection/transmission in ferrets. Bioluminescent imaging of ferrets infected with A/California/04/2009 H1N1 virus (CA/09) encoding NanoLuc (NLuc) luciferase provides the first real-time...

  13. Established rheumatoid arthritis - new imaging modalities

    McQueen, Fiona M; Østergaard, Mikkel

    2007-01-01

    ) and single photon emission tomography (SPECT) can reveal actively metabolizing bone and the proliferation of synovial cellsvia radioactive labeling. Bioluminescence and fluorescence reflectance imaging are other approaches that allow imaging, and potentially the delivery of therapeutic agents, at a...

  14. Established rheumatoid arthritis - new imaging modalities

    McQueen, Fiona M; Østergaard, Mikkel

    2007-01-01

    ) and single photon emission tomography (SPECT) can reveal actively metabolizing bone and the proliferation of synovial cells via radioactive labeling. Bioluminescence and fluorescence reflectance imaging are other approaches that allow imaging, and potentially the delivery of therapeutic agents, at a...

  15. Time series hyperspectral chemical imaging data: challenges, solutions and applications.

    Gowen, A A; Marini, F; Esquerre, C; O'Donnell, C; Downey, G; Burger, J

    2011-10-31

    Hyperspectral chemical imaging (HCI) integrates imaging and spectroscopy resulting in three-dimensional data structures, hypercubes, with two spatial and one wavelength dimension. Each spatial image pixel in a hypercube contains a spectrum with >100 datapoints. While HCI facilitates enhanced monitoring of multi-component systems; time series HCI offers the possibility of a more comprehensive understanding of the dynamics of such systems and processes. This implies a need for modeling strategies that can cope with the large multivariate data structures generated in time series HCI experiments. The challenges posed by such data include dimensionality reduction, temporal morphological variation of samples and instrumental drift. This article presents potential solutions to these challenges, including multiway analysis, object tracking, multivariate curve resolution and non-linear regression. Several real world examples of time series HCI data are presented to illustrate the proposed solutions. PMID:21962370

  16. Real-time particle image velocimetry based on FPGA technology

    Particle image velocimetry (PIV), based on laser sheet, is a method for image processing and calculation of distributed velocity fields.It is well established as a fluid dynamics measurement tool, being applied to liquid, gases and multiphase flows.Images of particles are processed by means of computationally demanding algorithms, what makes its real-time implementation difficult.The most probable displacements are found applying two dimensional cross-correlation function. In this work, we detail how it is possible to achieve real-time visualization of PIV method by designing an adaptive embedded architecture based on FPGA technology.We show first results of a physical field of velocity calculated by this platform system in a real-time approach.

  17. Compact wearable dual-mode imaging system for real-time fluorescence image-guided surgery

    Zhu, Nan; Huang, Chih-Yu; Mondal, Suman; Gao, Shengkui; Huang, Chongyuan; Gruev, Viktor; Achilefu, Samuel; Liang, Rongguang

    2015-09-01

    A wearable all-plastic imaging system for real-time fluorescence image-guided surgery is presented. The compact size of the system is especially suitable for applications in the operating room. The system consists of a dual-mode imaging system, see-through goggle, autofocusing, and auto-contrast tuning modules. The paper will discuss the system design and demonstrate the system performance.

  18. Compact wearable dual-mode imaging system for real-time fluorescence image-guided surgery.

    Zhu, Nan; Huang, Chih-Yu; Mondal, Suman; Gao, Shengkui; Huang, Chongyuan; Gruev, Viktor; Achilefu, Samuel; Liang, Rongguang

    2015-09-01

    A wearable all-plastic imaging system for real-time fluorescence image-guided surgery is presented. The compact size of the system is especially suitable for applications in the operating room. The system consists of a dual-mode imaging system, see-through goggle, autofocusing, and auto-contrast tuning modules. The paper will discuss the system design and demonstrate the system performance. PMID:26358823

  19. Real-time image processing in a flat-panel solid state medical fluoroscopic imaging system

    Klausmeier-Brown, Martin E.; Allen, Maxwell J.; Boyce, Sarah J.; Colbeth, Richard E.; Gilblom, David L.; Job, Isaias D.; Koenig, M.; Pavkovich, John M.; Wright, Michael D.; Yu, Jiann M.

    1998-03-01

    This paper describes a real-time image processing system for correction and enhancement of fluoroscopic (video X-ray) image data obtained from a large area, flat-panel, solid- state medical image sensor. The amorphous silicon sensor is 1536 X 1920 pixels, measuring 20 X 25 cm; for operation at 30 frames per second, the real pixel data rate is approximately 45 MB/sec.

  20. Rapid detection (4 h) of methicillin-resistant Staphylococcus aureus by a bioluminescence method.

    Park, C H; Hixon, D L; McLaughlin, C M; Cook, J F

    1988-01-01

    A 4-h bioluminescence method for methicillin susceptibility determination was compared with reference methods. Of the Staphylococcus aureus strains tested, 80 were methicillin resistant, 180 were methicillin susceptible, and 10 were borderline susceptible. There was 100% correlation between bioluminescence and reference methods for methicillin-susceptible and methicillin-resistant strains. All borderline-susceptible strains were identified as methicillin resistant by bioluminescence.

  1. D City Transformations by Time Series of Aerial Images

    Adami, A.

    2015-02-01

    Recent photogrammetric applications, based on dense image matching algorithms, allow to use not only images acquired by digital cameras, amateur or not, but also to recover the vast heritage of analogue photographs. This possibility opens up many possibilities in the use and enhancement of existing photos heritage. The research of the original figuration of old buildings, the virtual reconstruction of disappeared architectures and the study of urban development are some of the application areas that exploit the great cultural heritage of photography. Nevertheless there are some restrictions in the use of historical images for automatic reconstruction of buildings such as image quality, availability of camera parameters and ineffective geometry of image acquisition. These constrains are very hard to solve and it is difficult to discover good dataset in the case of terrestrial close range photogrammetry for the above reasons. Even the photographic archives of museums and superintendence, while retaining a wealth of documentation, have no dataset for a dense image matching approach. Compared to the vast collection of historical photos, the class of aerial photos meets both criteria stated above. In this paper historical aerial photographs are used with dense image matching algorithms to realize 3d models of a city in different years. The models can be used to study the urban development of the city and its changes through time. The application relates to the city centre of Verona, for which some time series of aerial photographs have been retrieved. The models obtained in this way allowed, right away, to observe the urban development of the city, the places of expansion and new urban areas. But a more interesting aspect emerged from the analytical comparison between models. The difference, as the Euclidean distance, between two models gives information about new buildings or demolitions. As considering accuracy it is necessary point out that the quality of final observations from model comparison depends on several aspects such as image quality, image scale and marker accuracy from cartography.

  2. Serial time-encoded amplified imaging for real-time observation of fast dynamic phenomena.

    Goda, K; Tsia, K K; Jalali, B

    2009-04-30

    Ultrafast real-time optical imaging is an indispensable tool for studying dynamical events such as shock waves, chemical dynamics in living cells, neural activity, laser surgery and microfluidics. However, conventional CCDs (charge-coupled devices) and their complementary metal-oxide-semiconductor (CMOS) counterparts are incapable of capturing fast dynamical processes with high sensitivity and resolution. This is due in part to a technological limitation-it takes time to read out the data from sensor arrays. Also, there is the fundamental compromise between sensitivity and frame rate; at high frame rates, fewer photons are collected during each frame-a problem that affects nearly all optical imaging systems. Here we report an imaging method that overcomes these limitations and offers frame rates that are at least 1,000 times faster than those of conventional CCDs. Our technique maps a two-dimensional (2D) image into a serial time-domain data stream and simultaneously amplifies the image in the optical domain. We capture an entire 2D image using a single-pixel photodetector and achieve a net image amplification of 25 dB (a factor of 316). This overcomes the compromise between sensitivity and frame rate without resorting to cooling and high-intensity illumination. As a proof of concept, we perform continuous real-time imaging at a frame speed of 163 ns (a frame rate of 6.1 MHz) and a shutter speed of 440 ps. We also demonstrate real-time imaging of microfluidic flow and phase-explosion effects that occur during laser ablation. PMID:19407796

  3. Time Domain Terahertz (T-Ray) Subsurface and Structural Imaging

    Zimdars, David; White, Jeffrey S.; Stuk, G.; Chernovsky, A.; Fichter, G.; Sucha, G.; Williamson, S.

    2007-03-01

    The technology, methods, and examples of high speed time domain terahertz (T-Ray) imaging non-destructive examination (NDE) for 2 and 3 dimensional structural and material content characterization are discussed. T-Ray imaging can be utilized for non-contact transmission and/or monostatic reflection inspection of non-conductive materials such as plastics, foam, composites, ceramics, paper, wood and glass. Example subsurface homeland security images of concealed items in baggage and on personnel are shown. We tabulate attenuation and penetration characteristics through a selection of building materials, and demonstrate the ability of T-ray instrumentation to sub-surface image building structures such as wall framing and interior wiring and conduits.

  4. Communication: Time- and space-sliced velocity map electron imaging

    Lee, Suk Kyoung; Lin, Yun Fei; Lingenfelter, Steven; Fan, Lin; Winney, Alexander H.; Li, Wen, E-mail: wli@chem.wayne.edu [Department of Chemistry, Wayne State University, Detroit, Michigan 48202 (United States)

    2014-12-14

    We develop a new method to achieve slice electron imaging using a conventional velocity map imaging apparatus with two additional components: a fast frame complementary metal-oxide semiconductor camera and a high-speed digitizer. The setup was previously shown to be capable of 3D detection and coincidence measurements of ions. Here, we show that when this method is applied to electron imaging, a time slice of 32 ps and a spatial slice of less than 1 mm thick can be achieved. Each slice directly extracts 3D velocity distributions of electrons and provides electron velocity distributions that are impossible or difficult to obtain with a standard 2D imaging electron detector.

  5. Communication: Time- and space-sliced velocity map electron imaging

    We develop a new method to achieve slice electron imaging using a conventional velocity map imaging apparatus with two additional components: a fast frame complementary metal-oxide semiconductor camera and a high-speed digitizer. The setup was previously shown to be capable of 3D detection and coincidence measurements of ions. Here, we show that when this method is applied to electron imaging, a time slice of 32 ps and a spatial slice of less than 1 mm thick can be achieved. Each slice directly extracts 3D velocity distributions of electrons and provides electron velocity distributions that are impossible or difficult to obtain with a standard 2D imaging electron detector

  6. Time-lapse Raman imaging of osteoblast differentiation

    Hashimoto, Aya; Yamaguchi, Yoshinori; Chiu, Liang-Da; Morimoto, Chiaki; Fujita, Katsumasa; Takedachi, Masahide; Kawata, Satoshi; Murakami, Shinya; Tamiya, Eiichi

    2015-07-01

    Osteoblastic mineralization occurs during the early stages of bone formation. During this mineralization, hydroxyapatite (HA), a major component of bone, is synthesized, generating hard tissue. Many of the mechanisms driving biomineralization remain unclear because the traditional biochemical assays used to investigate them are destructive techniques incompatible with viable cells. To determine the temporal changes in mineralization-related biomolecules at mineralization spots, we performed time-lapse Raman imaging of mouse osteoblasts at a subcellular resolution throughout the mineralization process. Raman imaging enabled us to analyze the dynamics of the related biomolecules at mineralization spots throughout the entire process of mineralization. Here, we stimulated KUSA-A1 cells to differentiate into osteoblasts and conducted time-lapse Raman imaging on them every 4 hours for 24 hours, beginning 5 days after the stimulation. The HA and cytochrome c Raman bands were used as markers for osteoblastic mineralization and apoptosis. From the Raman images successfully acquired throughout the mineralization process, we found that β-carotene acts as a biomarker that indicates the initiation of osteoblastic mineralization. A fluctuation of cytochrome c concentration, which indicates cell apoptosis, was also observed during mineralization. We expect time-lapse Raman imaging to help us to further elucidate osteoblastic mineralization mechanisms that have previously been unobservable.

  7. A fast reconstruction algorithm for bioluminescence tomography based on smoothed l0 norm regularization

    He, Xiaowei; Yu, Jingjing; Geng, Guohua; Guo, Hongbo

    2013-10-01

    As an important optical molecular imaging technique, bioluminescence tomography (BLT) offers an inexpensive and sensitive means for non-invasively imaging a variety of physiological and pathological activities at cellular and molecular levels in living small animals. The key problem of BLT is to recover the distribution of the internal bioluminescence sources from limited measurements on the surface. Considering the sparsity of the light source distribution, we directly formulate the inverse problem of BLT into an l0-norm minimization model and present a smoothed l0-norm (SL0) based reconstruction algorithm. By approximating the discontinuous l0 norm with a suitable continuous function, the SL0 norm method solves the problem of intractable computational load of the minimal l0 search as well as high sensitivity of l0-norm to noise. Numerical experiments on a mouse atlas demonstrate that the proposed SL0 norm based reconstruction method can obtain whole domain reconstruction without any a priori knowledge of the source permissible region, yielding almost the same reconstruction results to those of l1 norm methods.

  8. Real-time quantitative phase imaging for cell studies

    Pham, Hoa Vinh

    Most biological cells are not clearly visible with a bright field microscope. Several methods have been developed to improve contrast in cell imaging, including use of exogenous contrast agents such as fluorescence microscopy, as well as utilizing properties of light-specimen interaction for optics design, to reveal the endogenous contrast, such as phase contrast microscopy (PCM) and differential interference contrast (DIC) microscopy. Although PCM and DIC methods significantly improve the image contrast without the need for staining agents, they only provide qualitative information about the phase change induced by the cells as light passes through them. Quantitative phase imaging (QPI) has recently emerged as an effective imaging tool which provides not only better image contrast but also cell-induced phase shifts in the optical pathlength, thus allowing nanometer-scale measurements of structures and dynamics of the cells. Other important aspects of an imaging system are its imaging speed and throughput. High-throughput, high-speed, real-time quantitative phase imaging with high spatial and temporal sensitivity is highly desirable in many applications including applied physics and biomedicine. In this dissertation, to address this need, I discuss the development of such an imaging system that includes the white light diffraction phase microscopy (wDPM), a new optical imaging method, and image reconstruction/analysis algorithms using graphics processing units (GPUs). wDPM can measure optical pathlength changes at nanometer scale both spatially and temporally with single-shot image acquisition, enabling very fast imaging. I also exploit the broadband spectrum of white light used as the light source in wDPM to develop a system called spectroscopic diffraction phase microscopy (sDPM). This sDPM system allows QPI measurements at several wavelengths, which solves the problem of thickness and refractive index coupling in the phase shifts induced by the cell, and which also may help visualize more-complex cell structures. Owing to its high spatial and temporal sensitivity and single-shot acquisition, wDPM enables measurement of nanometer-scale dynamic processes of cells at very high rate and measurement of cell growth because of the linear relationship between a cell-induced phase shift and its dry mass. The parallel algorithms and software tools I developed allow real-time QPI imaging and online image analysis at frame rates of up to 40 megapixel-size images per second. This capability allows very high throughput of several thousands of cells in imaging mode and eliminates the need of storing the images since we only need to store processed data, which is much smaller in storage size. Finally, I present the capability of the system by showing an application in red blood cell screening, which can be used as a diagnostic tool in blood testing and may pave the way for digital hematology and remote diagnostics.

  9. Space, time, error, and power optimization of image compression transforms

    Schmalz, Mark S.; Ritter, Gerhard X.; Caimi, Frank M.

    2000-11-01

    The implementation of an image compression transform on one or more small, embedded processors typically involves stringent constraints on power consumption and form factor. Traditional methods of optimizing compression algorithm performance typically emphasize joint minimization of space and time complexity, often without significant consideration of arithmetic accuracy or power consumption. However, small autonomous imaging platforms typically require joint optimization of space, time, error (or accuracy), and power (STEP) parameters, which the authors call STEP optimization. In response to implementational constraints on space and power consumption, the authors have developed systems and techniques for STEP optimization that are based on recent research in VLSI circuit design, as well as extensive previous work in system optimization. Building on the authors' previous research in embedded processors as well as adaptive or reconfigurable computing, it is possible to produce system-independent STEP optimization that can be customized for a given set of system-specific constraints. This approach is particularly useful when algorithms for image and signal processing (ISP) computer vision (CV), or automated target recognition (ATR), expressed in a machine- independent notation, are mapped to one or more heterogeneous processors (e.g., digital signal processors or DSPs, SIMD mesh processors, or reconfigurable logic). Following a theoretical summary, this paper illustrates various STEP optimization techniques via case studies, for example, real-time compression of underwater imagery on board an autonomous vehicle. Optimization algorithms are taken from the literature, and error profiling/analysis methodologies developed in the authors' previous research are employed. This yields a more rigorous basis for the simulation and evaluation of compression algorithms on a wide variety of hardware models. In this study, image algebra is employed as the notation of choice. Developed under DARPA and Air Force sponsorship at University of Florida, image algebra is a rigorous, concise notation that unifies linear and nonlinear mathematics in the image domain. Image algebra has been implemented on numerous workstations, parallel processors, and embedded processors, several of which are modeled in this study.

  10. Real-Time Air Pollutants Rendering based on Image Processing

    Demin Wang

    2011-11-01

    Full Text Available This paper presents a new method for realistic real-time rendering of air pollutants based on image processing. The air pollutants’ variable density can create many shapes of mist what can add a realistic environment to virtual scene. In order to achieve a realistic effect, we further enhance thus obtained air pollution data getting from monitor in spatial domain. In the proposed method we map the densities of air pollutants to different gray levels, and visualize them by blending those gray levels with background images. The proposed method can also visualize large-scale air pollution data from different viewpoints in real-time and provide the resulting image with any resolution theoretically, which is very important and favorable for the Internet transmission.

  11. Time-resolved neutron imaging at ANTARES cold neutron beamline

    Tremsin, A S; Tittelmeier, K; Schillinger, B; Schulz, M; Lerche, M; Feller, W B

    2015-01-01

    In non-destructive evaluation with X-rays light elements embedded in dense, heavy (or high-Z) matrices show little contrast and their structural details can hardly be revealed. Neutron radiography, on the other hand, provides a solution for those cases, in particular for hydrogenous materials, owing to the large neutron scattering cross section of hydrogen and uncorrelated dependency of neutron cross section on the atomic number. The majority of neutron imaging experiments at the present time is conducted with static objects mainly due to the limited flux intensity of neutron beamline facilities and sometimes due to the limitations of the detectors. However, some applications require the studies of dynamic phenomena and can now be conducted at several high intensity beamlines such as the recently rebuilt ANTARES beam line at the FRM-II reactor. In this paper we demonstrate the capabilities of time resolved imaging for repetitive processes, where different phases of the process can be imaged simultaneously and...

  12. In vivo real-time volumetric synthetic aperture ultrasound imaging

    Bouzari, Hamed; Rasmussen, Morten F.; Brandt, Andreas H.; Stuart, Matthias B.; Nikolov, Svetoslav; Jensen, Jrgen A.

    2015-03-01

    Synthetic aperture (SA) imaging can be used to achieve real-time volumetric ultrasound imaging using 2-D array transducers. The sensitivity of SA imaging is improved by maximizing the acoustic output, but one must consider the limitations of an ultrasound system, both technical and biological. This paper investigates the in vivo applicability and sensitivity of volumetric SA imaging. Utilizing the transmit events to generate a set of virtual point sources, a frame rate of 25 Hz for a 90 90 field-of-view was achieved. data were obtained using a 3.5 MHz 32 32 elements 2-D phased array transducer connected to the experimental scanner (SARUS). Proper scaling is applied to the excitation signal such that intensity levels are in compliance with the U.S. Food and Drug Administration regulations for in vivo ultrasound imaging. The measured Mechanical Index and spatial-peak-temporal-average intensity for parallel beam-forming (PB) are 0.83 and 377.5mW/cm2, and for SA are 0.48 and 329.5mW/cm2. A human kidney was volumetrically imaged with SA and PB techniques simultaneously. Two radiologists for evaluation of the volumetric SA were consulted by means of a questionnaire on the level of details perceivable in the beam-formed images. The comparison was against PB based on the in vivo data. The feedback from the domain experts indicates that volumetric SA images internal body structures with a better contrast resolution compared to PB at all positions in the entire imaged volume. Furthermore, the autocovariance of a homogeneous area in the in vivo SA data, had 23.5% smaller width at the half of its maximum value compared to PB.

  13. A Simple Fusion Method for Image Time Series Based on the Estimation of Image Temporal Validity

    Mar Bisquert

    2015-01-01

    Full Text Available High-spatial-resolution satellites usually have the constraint of a low temporal frequency, which leads to long periods without information in cloudy areas. Furthermore, low-spatial-resolution satellites have higher revisit cycles. Combining information from high- and low- spatial-resolution satellites is thought a key factor for studies that require dense time series of high-resolution images, e.g., crop monitoring. There are several fusion methods in the bibliography, but they are time-consuming and complicated to implement. Moreover, the local evaluation of the fused images is rarely analyzed. In this paper, we present a simple and fast fusion method based on a weighted average of two input images (H and L, which are weighted by their temporal validity to the image to be fused. The method was applied to two years (2009–2010 of Landsat and MODIS (MODerate Imaging Spectroradiometer images that were acquired over a cropped area in Brazil. The fusion method was evaluated at global and local scales. The results show that the fused images reproduced reliable crop temporal profiles and correctly delineated the boundaries between two neighboring fields. The greatest advantages of the proposed method are the execution time and ease of use, which allow us to obtain a fused image in less than five minutes.

  14. Real-time operator interactive MR imaging of the heart with ultrashort repetition time techniques

    The purpose of this paper is to generate in real-time a MR imaging sequence of the heart using snapshot techniques. A fast MR pulse sequence is triggered by the electrocardiographic (ECG) signal. Data acquisition begins following a controllable delay after the R wave. The authors use 32 to 64 phase encodings with ultrashort (6.0-msec) TR times, yielding an image-acquisition time of 192 to 384 msec. To suppress the signal from blood in the cardiac chambers, saturation pulses are applied. For image reconstruction, the authors use the MR fluoroscopic apparatus previously developed. For each cardiac cycle, an image is reconstructed and displayed within 120 msec after the termination of acquisition

  15. Segmentation of Time-Lapse Images with Focus on Microscopic Images of Cells

    Soukup, Jindřich; Císař, P.; Šroubek, Filip

    Berlin : Springer-Verlag, 2013 - (Petrosino, A.), s. 71-80 ISBN 978-3-642-41183-0. - (Lecture Notes in Computer Science. Image Processing, Computer Vision, Pattern Recognition, and Graphics. 8157). [International Conference on Image Analysis and Processing. Naples (IT), 11.09.2013-13.09.2013] R&D Projects: GA ČR GA13-29225S Grant ostatní: Grantová agentura UK(CZ) GAUK 914813/2013; GA MŠk(CZ) ED2.1.00/01.0024 Institutional support: RVO:67985556 Keywords : segmentation * time-lapse * microscopy imaging * phase constrast Subject RIV: JD - Computer Applications, Robotics http://library.utia.cas.cz/separaty/2013/ZOI/soukup- segmentation of time-lapse image s with focus on microscopic image s of cells.pdf

  16. Time of Flight Diffraction and Imaging (tofdi) Combining B-Scans and Cross-Sectional Imaging

    Petcher, P. A.; Dixon, S.

    2011-06-01

    Time of Flight Diffraction and Imaging (ToFDI), based on Time of Flight Diffraction (ToFD), uses a sparse transducer array (laser-EMAT for non-contact applications), and adds an imaging stage based on multiple wave mode (and mode-converted) ultrasound scattering by defects. B-scans are processed to remove direct and reflected surface waves, enhance parabolas, and combine multiple B-scans. Outputting an improved B-scan and a cross-sectional image, the final objective is the automated detection, identification, positioning and sizing for all defects in a sample.

  17. Time-of-flight imaging of invisibility cloaks

    Halimeh, Jad C.; Wegener, Martin

    2012-01-01

    As invisibility cloaking has recently become experimental reality, it is interesting to explore ways to reveal remaining imperfections. In essence, the idea of most invisibility cloaks is to recover the optical path lengths without an object (to be made invisible) by a suitable arrangement around that object. Optical path length is proportional to the time of flight of a light ray or to the optical phase accumulated by a light wave. Thus, time-of-flight images provide a direct and intuitive t...

  18. Real-time image fusion involving diagnostic ultrasound

    Ewertsen, Caroline; Săftoiu, Adrian; Gruionu, Lucian G; Karstrup, Steen; Nielsen, Michael B

    2013-01-01

    The aim of our article is to give an overview of the current and future possibilities of real-time image fusion involving ultrasound. We present a review of the existing English-language peer-reviewed literature assessing this technique, which covers technical solutions (for ultrasound and...

  19. Automated Hierarchical Time Gain Compensation for In Vivo Ultrasound Imaging

    Moshavegh, Ramin; Hemmsen, Martin Christian; Martins, Bo; Brandt, Andreas Hjelm; Lindskov Hansen, Kristoffer; Nielsen, Michael Bachmann; Jensen, Jørgen Arendt

    2015-01-01

    Time gain compensation (TGC) is essential to ensure the optimal image quality of the clinical ultrasound scans. When large fluid collections are present within the scan plane, the attenuation distribution is changed drastically and TGC compensation becomes challenging. This paper presents an auto...

  20. Change detection in a time series of polarimetric SAR images

    Skriver, Henning; Nielsen, Allan Aasbjerg; Conradsen, Knut

    to the complex Wishart distribution and demonstrate its application to change detection in truly multi-temporal, polarimetric SAR data. Results will be shown that demonstrate the difference between applying to time series of polarimetric SAR images, pairwise comparisons or the new omnibus test...

  1. Diffeomorphic image registration with automatic time-step adjustment

    Pai, Akshay Sadananda Uppinakudru; Klein, S.; Sommer, Stefan Horst; Darkner, Sune; Sporring, Jon; Nielsen, Mads

    In this paper, we propose an automated Euler's time-step adjustment scheme for diffeomorphic image registration using stationary velocity fields (SVFs). The proposed variational problem aims at bounding the inverse consistency error by adaptively adjusting the number of Euler's step required to...

  2. Bubble masks for time-encoded imaging of fast neutrons.

    Brubaker, Erik; Brennan, James S.; Marleau, Peter; Nowack, Aaron B.; Steele, John; Sweany, Melinda; Throckmorton, Daniel J.

    2013-09-01

    Time-encoded imaging is an approach to directional radiation detection that is being developed at SNL with a focus on fast neutron directional detection. In this technique, a time modulation of a detected neutron signal is induced-typically, a moving mask that attenuates neutrons with a time structure that depends on the source position. An important challenge in time-encoded imaging is to develop high-resolution two-dimensional imaging capabilities; building a mechanically moving high-resolution mask presents challenges both theoretical and technical. We have investigated an alternative to mechanical masks that replaces the solid mask with a liquid such as mineral oil. Instead of fixed blocks of solid material that move in pre-defined patterns, the oil is contained in tubing structures, and carefully introduced air gaps-bubbles-propagate through the tubing, generating moving patterns of oil mask elements and air apertures. Compared to current moving-mask techniques, the bubble mask is simple, since mechanical motion is replaced by gravity-driven bubble propagation; it is flexible, since arbitrary bubble patterns can be generated by a software-controlled valve actuator; and it is potentially high performance, since the tubing and bubble size can be tuned for high-resolution imaging requirements. We have built and tested various single-tube mask elements, and will present results on bubble introduction and propagation as a function of tubing size and cross-sectional shape; real-time bubble position tracking; neutron source imaging tests; and reconstruction techniques demonstrated on simple test data as well as a simulated full detector system.

  3. A miniature real-time volumetric ultrasound imaging system

    Wygant, Ira O.; Yeh, David T.; Zhuang, Xuefeng; Nikoozadeh, Amin; Oralkan, Omer; Ergun, Arif S.; Karaman, Mustafa; Khuri-Yakub, Butrus T.

    2005-04-01

    Progress made in the development of a miniature real-time volumetric ultrasound imaging system is presented. This system is targeted for use in a 5-mm endoscopic channel and will provide real-time, 30-mm deep, volumetric images. It is being developed as a clinically useful device, to demonstrate a means of integrating the front-end electronics with the transducer array, and to demonstrate the advantages of the capacitive micromachined ultrasonic transducer (CMUT) technology for medical imaging. Presented here is the progress made towards the initial implementation of this system, which is based on a two-dimensional, 16x16 CMUT array. Each CMUT element is 250 um by 250 um and has a 5 MHz center frequency. The elements are connected to bond pads on the back side of the array with 400-um long through-wafer interconnects. The transducer array is flip-chip bonded to a custom-designed integrated circuit that comprises the front-end electronics. The result is that each transducer element is connected to a dedicated pulser and low-noise preamplifier. The pulser generates 25-V, 100-ns wide, unipolar pulses. The preamplifier has an approximate transimpedance gain of 500 kOhm and 3-dB bandwidth of 10 MHz. In the first implementation of the system, one element at a time can be selected for transmit and receive and thus synthetic aperture images can be generated. In future implementations, 16 channels will be active at a given time. These channels will connect to an FPGA-based data acquisition system for real-time image reconstruction.

  4. Time-resolved fluorescence imaging in biology and medicine

    Fluorescence lifetime imaging is a rather new and effective tool that can be used to study complex biological samples, either at microscopic or macroscopic levels. The map of the fluorescence lifetime allows one to discriminate amongst different fluorophores and to achieve valuable insights into the behaviour of emitting molecules, leading to information like local pH, oxygen concentration in cells, etc. Moreover, the distribution in space of any fluorescent marker achievable with this technique can be exploited for diagnostic purposes in medicine. After a brief introduction on the motivations for applying fluorescence lifetime imaging in biology and medicine, the basic principles of this technique will be addressed. Then, the two possible implementations of fluorescence lifetime imaging (i.e. the frequency domain and the time domain methods) will be presented. For this purpose, special attention will be devoted to practical aspects of image acquisition and processing, especially for what concerns the time domain method. Then, the analysis of the state-of-the-art systems will include a brief discussion on new concepts that have recently been introduced in this research field. Finally, two interesting applications of fluorescence lifetime imaging will be presented. The former refers to skin tumour detection and has been successfully applied in a preliminary clinical trial, the latter regards DNA chips reading and has been tested only at laboratory level, yet it has produced promising results for its future implementation in commercial systems. (author)

  5. Muscle segmentation in time series images of Drosophila metamorphosis.

    Yadav, Kuleesha; Feng Lin; Wasser, Martin

    2015-08-01

    In order to study genes associated with muscular disorders, we characterize the phenotypic changes in Drosophila muscle cells during metamorphosis caused by genetic perturbations. We collect in vivo images of muscle fibers during remodeling of larval to adult muscles. In this paper, we focus on the new image processing pipeline designed to quantify the changes in shape and size of muscles. We propose a new two-step approach to muscle segmentation in time series images. First, we implement a watershed algorithm to divide the image into edge-preserving regions, and then, we classify these regions into muscle and non-muscle classes on the basis of shape and intensity. The advantage of our method is two-fold: First, better results are obtained because classification of regions is constrained by the shape of muscle cell from previous time point; and secondly, minimal user intervention results in faster processing time. The segmentation results are used to compare the changes in cell size between controls and reduction of the autophagy related gene Atg 9 during Drosophila metamorphosis. PMID:26736944

  6. Imaging the time sequence of latent electrostatic fingerprints

    Watson, P.; Prance, R. J.; Prance, H.; Beardsmore-Rust, S. T.

    2010-10-01

    Biometric identification for forensic investigations and security continues to depend on classic fingerprinting in many instances. Existing techniques rely on either visible deposits or hidden (latent) fingerprints resulting from the transfer of residues from the finger to the surface. However, one of the limitations of classic fingerprinting, for use as forensic evidence, is in determining a time sequence of events. It is extremely difficult to establish a timeline, from fingerprint evidence alone. We present the capability of a new technique which images the electrical charge deposited by tribocharging when a finger contacts an electrically insulated surface. The method is applicable to insulating surfaces and has been tested on PVC, PTFE, Acetate and PVDF sheets. The latent electrostatic charge pattern is detected using a novel, microscopic, electric potential sensor. The sensor is capable of imaging static charge distributions non-invasively, with no discharging effect on the sample. We present data showing the decay of the charge image with time, over a period up to 14 days. This capability has two major implications. First this technique does not suffer from ambiguities caused by a history of old fingerprints and second it has the potential to allow the time sequence of recent charge fingerprint images to be determined.

  7. Two-dimensional random arrays for real time volumetric imaging

    Davidsen, Richard E.; Jensen, Jørgen Arendt; Smith, Stephen W.

    1994-01-01

    beams. A random array with Gaussian distribution of transmitters and uniform distribution of receivers was found to have better resolution and depth-of-field than both a Mills cross array and a random array with uniform distribution of both transmit and receive elements. The Gaussian random array was...... real time volumetric imaging system, which employs a wide transmit beam and receive mode parallel processing to increase image frame rate. Depth-of-field comparisons were made from simulated on-axis and off-axis beamplots at ranges from 30 to 160 mm for both coaxial and offset transmit and receive...

  8. Terahertz time-domain spectroscopy and imaging of artificial RNA

    Fischer, Bernd M.; Hoffmann, Matthias; Helm, Hanspeter; Wilk, Rafal; Rutz, Frank; Kleine-Ostermann, Thomas; Koch, Martin; Jepsen, Peter Uhd

    2005-01-01

    We use terahertz time-domain spectroscopy (THz-TDS) to measure the far-infrared dielectric function of two artificial RNA single strands, composed of polyadenylic acid (poly-A) and polycytidylic acid (poly-C). We find a significant difference in the absorption between the two types of RNA strands......, and we show that we can use this difference to record images of spot arrays of the RNA strands. Under controlled conditions it is possible to use the THz image to distinguish between the two RNA strands. We discuss the requirements to sample preparation imposed by the lack of sharp spectral features...... in the absorption spectra....

  9. Real-time digital X-ray subtraction imaging

    A diagnostic anatomical X-ray apparatus comprising a converter and a television camera for converting an X-ray image of a subject into a series of television fields of video signals is described in detail. A digital memory system stores and integrates the video signals over a time interval corresponding to a plurality of successive television fields. The integrated video signals are recovered from storage and fed to a digital or analogue subtractor, the resulting output being displayed on a television monitor. Thus the display represents on-going changes in the anatomical X-ray image. In a modification, successive groups of fields are stored and integrated in three memories, cyclically, and subtractions are performed between successive pieces of integrated signals to provide a display of successive alterations in the X-ray image. For investigations of the heart, the integrating interval should be of the order of one cardiac cycle. (author)

  10. Cellular Neural Network for Real Time Image Processing

    Since their introduction in 1988, Cellular Nonlinear Networks (CNNs) have found a key role as image processing instruments. Thanks to their structure they are able of processing individual pixels in a parallel way providing fast image processing capabilities that has been applied to a wide range of field among which nuclear fusion. In the last years, indeed, visible and infrared video cameras have become more and more important in tokamak fusion experiments for the twofold aim of understanding the physics and monitoring the safety of the operation. Examining the output of these cameras in real-time can provide significant information for plasma control and safety of the machines. The potentiality of CNNs can be exploited to this aim. To demonstrate the feasibility of the approach, CNN image processing has been applied to several tasks both at the Frascati Tokamak Upgrade (FTU) and the Joint European Torus (JET)

  11. Super-resolved imaging with ultimate time resolution

    Ashida, Yuto

    2015-01-01

    Precisely and accurately locating point objects is a long-standing common thread in science. Super-resolved imaging of single molecules has revolutionized our view of quasi-static nanostructures $\\it{in-vivo}$. A wide-field approach based on localizing individual fluorophores has emerged as a versatile method to surpass the standard resolution limit. In those techniques, the super-resolution is realized by sparse photoactivation and localization together with the statistical analysis based on point spread functions. Nevertheless, the slow temporal resolution of super-resolved imaging severely restricts the utility to the study of live-cell phenomena. Clearly, a major breakthrough to observe fast, nanoscale dynamics needs to be made. Here we present a super-resolved imaging method that achieves the theoretical-limit time resolution. By invoking information theory, we can achieve the robust localization of overlapped light emitters at an order of magnitude faster speed than the conventional super-resolution mic...

  12. Toxin-antitoxin-stabilized reporter plasmids for biophotonic imaging of Group A streptococcus.

    Loh, Jacelyn M S; Proft, Thomas

    2013-11-01

    Bioluminescence is a rapid and cost-efficient optical imaging technology that allows the detection of bacteria in real-time during disease development. Here, we report a novel strategy to generate a wide range of bioluminescent group A streptococcus (GAS) strains by using a toxin-antitoxin-stabilized plasmid. The bacterial luciferin-luciferase operon (lux) or the firefly luciferase gene (ffluc) was introduced into GAS via a stabilized plasmid. The FFluc reporter gave significantly stronger bioluminescent signals than the Lux reporter, and was generally more stable. Plasmid-based luciferase reporters could easily be introduced into a variety of GAS strains and the signals correlated linearly with viable cell counts. Co-expression of the streptococcal ω-ε-ζ toxin-antitoxin operon provided segregational stability in the absence of antibiotics for at least 17 passages in vitro and up to 7 days in a mouse infection model. In addition, genome-integrated reporter constructs were also generated by site-specific recombination, but were found to be technically more challenging. The quick and efficient generation of various M-type GAS strains expressing plasmid-based luciferase reporters with comparable and quantifiable bioluminescence signals allows for comparative analysis of different GAS strains in vitro and in vivo. PMID:24061415

  13. The influence of SHFEMF on bioluminescence of V. Harveyi

    Exposure of bacteria V. harveyi grown on agar medium to 7 HHz electromagnetic field changes the intensity of their luminescence. It is suggested that the dynamics of the luminescence change reflects the adaptation processes in the microorganisms which accompany the electromao.netic field effect. The changes observed may be attributed to the temperature dependence of bioluminescence

  14. The mechanism of electronic excitation in the bacterial bioluminescent reaction

    The current state of the problem of formation of the electron-excited product in the chemiluminescent reaction that underlies the bacterial luminescence is analysed. Various schemes of chemical transformations capable of producing a bacterial bioluminescence emitter are presented. The problem of excitation of secondary emitters is considered; two possible mechanisms of their excitation are analysed.

  15. Bioluminescence: a fungal nightlight with an internal timer.

    Bechara, Etelvino J H

    2015-03-30

    A recent study shows that green light emission by Neonothopanus gardneri mushrooms, endemic to coconut forests of Northern Brazil, is controlled by a circadian clock. Furthermore, insects are attracted by the light, raising the possibility that bioluminescence functions in spore dispersal and fungal dissemination. PMID:25829013

  16. Time-of-flight imaging of invisibility cloaks.

    Halimeh, Jad C; Wegener, Martin

    2012-01-01

    As invisibility cloaking has recently become experimental reality, it is interesting to explore ways to reveal remaining imperfections. In essence, the idea of most invisibility cloaks is to recover the optical path lengths without an object (to be made invisible) by a suitable arrangement around that object. Optical path length is proportional to the time of flight of a light ray or to the optical phase accumulated by a light wave. Thus, time-of-flight images provide a direct and intuitive tool for probing imperfections. Indeed, recent phase-sensitive experiments on the carpet cloak have already made early steps in this direction. In the macroscopic world, time-of-flight images could be measured directly by light detection and ranging (LIDAR). Here, we show calculated time-of-flight images of the conformal Gaussian carpet cloak, the conformal grating cloak, the cylindrical free-space cloak, and of the invisible sphere. All results are obtained by using a ray-velocity equation of motion derived from Fermat's principle. PMID:22274329

  17. Time-of-flight imaging of invisibility cloaks

    Halimeh, Jad C

    2011-01-01

    As invisibility cloaking has recently become experimental reality, it is interesting to explore ways to reveal remaining imperfections. In essence, the idea of most invisibility cloaks is to recover the optical path lengths without an object (to be made invisible) by a suitable arrangement around that object. Optical path length is proportional to the time of flight of a light ray or to the optical phase accumulated by a light wave. Thus, time-of-flight images provide a direct and intuitive tool for probing imperfections. Indeed, recent phase-sensitive experiments on the carpet cloak have already made early steps in this direction. In the macroscopic world, time-of-flight images could be measured directly by light detection and ranging (LIDAR). Here, we show calculated time-of-flight images of the conformal Gaussian carpet cloak, the conformal grating cloak, the cylindrical free-space cloak, and of the invisible sphere. All results are obtained by using a ray-velocity equation of motion derived from Fermat's ...

  18. A Colour Image Quantization Algorithm for Time-Constrained Applications

    Wattanapong KURDTHONGMEE

    2005-06-01

    Full Text Available Many techniques have been proposed to quantize a digital colour image in order to reduce the representative number of colours to be suitable for presenting on different types of display screens. In addition, the techniques have been used to significantly reduce the amount of image data required to transfer over a communication network. Most of the published techniques are targetted for implementing on a general purpose multitasking computer with low restriction on time and resource utilizations. The drawback of these techniques relies on the fact that they cannot fulfill the requirement of some applications for real-time constraint and limited resources. In addition, most of the techniques are too complex for hardware realization. In this paper, an algorithm which is more suitable for time critical applications with an additional feature of simplicity to implement on FPGA (Field Programmable Gate Array platforms is proposed and the details of its implementation and experimentation are presented. The dominate point of the proposed algorithm relies on the fact that it utilizes the weighted sum of the nearest distance along the axis under consideration, which is nontrivial to calculate, instead of the squared Euclidean distance to find the axis to split during. Also, the proposed algorithm has proved that by reducing the number of subspaces to be considered during the variance representative value calculation from 8 to 2 subspaces, the quality of quantized images are comparable to the previously proposed approaches. This makes it possible to further speed up the computational time of the quantization algorithm.

  19. Automatic multimodal real-time tracking for image plane alignment in interventional Magnetic Resonance Imaging

    Interventional magnetic resonance imaging (MRI) aims at performing minimally invasive percutaneous interventions, such as tumor ablations and biopsies, under MRI guidance. During such interventions, the acquired MR image planes are typically aligned to the surgical instrument (needle) axis and to surrounding anatomical structures of interest in order to efficiently monitor the advancement in real-time of the instrument inside the patient's body. Object tracking inside the MRI is expected to facilitate and accelerate MR-guided interventions by allowing to automatically align the image planes to the surgical instrument. In this PhD thesis, an image-based work-flow is proposed and refined for automatic image plane alignment. An automatic tracking work-flow was developed, performing detection and tracking of a passive marker directly in clinical real-time images. This tracking work-flow is designed for fully automated image plane alignment, with minimization of tracking-dedicated time. Its main drawback is its inherent dependence on the slow clinical MRI update rate. First, the addition of motion estimation and prediction with a Kalman filter was investigated and improved the work-flow tracking performance. Second, a complementary optical sensor was used for multi-sensor tracking in order to decouple the tracking update rate from the MR image acquisition rate. Performance of the work-flow was evaluated with both computer simulations and experiments using an MR compatible test bed. Results show a high robustness of the multi-sensor tracking approach for dynamic image plane alignment, due to the combination of the individual strengths of each sensor. (author)

  20. Real-time mid-infrared imaging of living microorganisms.

    Haase, Katharina; Kröger-Lui, Niels; Pucci, Annemarie; Schönhals, Arthur; Petrich, Wolfgang

    2016-01-01

    The speed and efficiency of quantum cascade laser-based mid-infrared microspectroscopy are demonstrated using two different model organisms as examples. For the slowly moving Amoeba proteus, a quantum cascade laser is tuned over the wavelength range of 7.6 µm to 8.6 µm (wavenumbers 1320 cm(-1) and 1160 cm(-1) , respectively). The recording of a hyperspectral image takes 11.3 s whereby an average signal-to-noise ratio of 29 is achieved. The limits of time resolution are tested by imaging the fast moving Caenorhabditis elegans at a discrete wavenumber of 1265 cm(-1) . Mid-infrared imaging is performed with the 640 × 480 pixel video graphics array (VGA) standard and at a full-frame time resolution of 0.02 s (i.e. well above the most common frame rate standards). An average signal-to-noise ratio of 16 is obtained. To the best of our knowledge, these findings constitute the first mid-infrared imaging of living organisms at VGA standard and video frame rate. PMID:26572683

  1. Time-Reversal MUSIC Imaging with Time-Domain Gating Technique

    Choi, Heedong; Ogawa, Yasutaka; Nishimura, Toshihiko; Ohgane, Takeo

    A time-reversal (TR) approach with multiple signal classification (MUSIC) provides super-resolution for detection and localization using multistatic data collected from an array antenna system. The theory of TR-MUSIC assumes that the number of antenna elements is greater than that of scatterers (targets). Furthermore, it requires many sets of frequency-domain data (snapshots) in seriously noisy environments. Unfortunately, these conditions are not practical for real environments due to the restriction of a reasonable antenna structure as well as limited measurement time. We propose an approach that treats both noise reduction and relaxation of the transceiver restriction by using a time-domain gating technique accompanied with the Fourier transform before applying the TR-MUSIC imaging algorithm. Instead of utilizing the conventional multistatic data matrix (MDM), we employ a modified MDM obtained from the gating technique. The resulting imaging functions yield more reliable images with only a few snapshots regardless of the limitation of the antenna arrays.

  2. Timing and position response of a block detector for fast neutron time-of-flight imaging

    Our research effort seeks to improve the spatial and timing performance of a block detector made of a pixilated plastic scintillator (EJ-200), first demonstrated as part of Oak Ridge National Laboratory's Advanced Portable Neutron Imaging System. Improvement of the position and time response is necessary to achieve better resolution and contrast in the images of shielded special nuclear material. Time-of-flight is used to differentiate between gamma and different sources of neutrons (e.g., transmission and fission neutrons). Factors limiting the timing and position performance of the neutron detector have been revealed through simulations and measurements. Simulations have suggested that the degradation in the ability to resolve pixels in the neutron detector is due to those interactions occurring near the light guide. The energy deposition within the neutron detector is shown to affect position performance and imaging efficiency. This examination details how energy cuts improve the position performance and degrade the imaging efficiency. Measurements have shown the neutron detector to have a timing resolution of σ=238 ps. The majority of this timing uncertainty is from the depth-of-interaction (DOI) of the neutron which is confirmed by simulations and analytical calculations

  3. Timing and position response of a block detector for fast neutron time-of-flight imaging

    Laubach, M.A., E-mail: mlaubach@utk.edu [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Hayward, J.P., E-mail: jhayward@utk.edu [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Oak Ridge National Laboratory, 1 Bethel Valley Rd., Oak Ridge, TN 37831 (United States); Zhang, X., E-mail: xzhang39@utk.edu [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Cates, J.W., E-mail: jcates7@vols.utk.edu [Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996 (United States)

    2014-11-01

    Our research effort seeks to improve the spatial and timing performance of a block detector made of a pixilated plastic scintillator (EJ-200), first demonstrated as part of Oak Ridge National Laboratory's Advanced Portable Neutron Imaging System. Improvement of the position and time response is necessary to achieve better resolution and contrast in the images of shielded special nuclear material. Time-of-flight is used to differentiate between gamma and different sources of neutrons (e.g., transmission and fission neutrons). Factors limiting the timing and position performance of the neutron detector have been revealed through simulations and measurements. Simulations have suggested that the degradation in the ability to resolve pixels in the neutron detector is due to those interactions occurring near the light guide. The energy deposition within the neutron detector is shown to affect position performance and imaging efficiency. This examination details how energy cuts improve the position performance and degrade the imaging efficiency. Measurements have shown the neutron detector to have a timing resolution of σ=238 ps. The majority of this timing uncertainty is from the depth-of-interaction (DOI) of the neutron which is confirmed by simulations and analytical calculations.

  4. The Arabidopsis repressor of light signaling, COP1, is regulated by nuclear exclusion: Mutational analysis by bioluminescence resonance energy transfer

    Subramanian, Chitra; Kim, Byung-Hoon; Lyssenko, Nicholas N; Xu, Xiaodong; JOHNSON, Carl Hirschie; von Arnim, Albrecht G

    2004-01-01

    Bioluminescence resonance energy transfer (BRET) between Renilla luciferase and yellow fluorescent protein has been adapted to serve as a real-time reporter on protein-protein interactions in live plant cells by using the Arabidopsis Constitutive photomorphogenesis 1 (COP1) protein as a model system. COP1 is a repressor of light signal transduction that functions as part of a nuclear E3 ubiquitin ligase. COP1 possesses a leucine-rich nuclear-exclusion signal that resides in a domain implicate...

  5. Detection of heterogeneous substrate distributions in tumors and spheroids by bioluminescence

    Heterogeneous cell populations within solid tumors often limit non-surgical tumor therapies. Partially, the biological variability among cancer cells in vivo is attributable to a non-uniform oxygenation and pH distribution as a consequence of spatial and temporal heterogeneities in the tumor microcirculation. In order to evaluate whether such inhomogeneities may also be found in the distribution of nutrients and metabolites, a method, originally developed for the determination of regional substrate distributions in brain tissue; has been applied to cryobiopsies of human tumor xenografts and of tumors in patients. In addition, this method has been adapted to multicellular tumor spheroids of human origin. The bioluminescence reactions are enzymatically linked to the substrate of interest. A cold cyrostat section of the frozen enzyme solution is laid upon a frozen cryostat section of a tumor or of a spheroid. Bioluminescence recorded by film exposure occurs upon thawing these sections. The exposed film is then evaluated by microdensitometry and by special image analysis. The regional distributions of glucose, lactate and ATP are obtained in relative units. The results show that all substances investigated exhibit large regional differences reflecting a great heterogeneity of the metabolic micromilieu in malignant tumors and even within tumor spheroids

  6. Measurement of MEMS thermal actuator time constant using image blur

    A method of experimentally determining the time constants of MEMS thermal actuators from an analysis of blurred still camera images of high frequency motion is presented. The response of MEMS thermal actuators to harmonic excitation falls off with increasing frequency. An analytical derivation of the thermal frequency response is performed considering actuator arm conduction and conduction through air to the substrate. For the actuator in this study, the predicted time constant is 120125 s. Directly measuring this time constant would require sampling in the kHz range, well above the range of most cameras, which blur the image. The thermal time constant is computed by analyzing the sidewall profiles of a stationary actuator and of the actuator excited over a range of frequencies. The observed slope of the blurred sidewall profile changes with the frequency: the larger the amplitude of motion, the shallower the apparent slope. By numerically blurring the stationary profile, the relationship between the blur amplitude and the blurred slope is found. From this and the measured slopes, the blur amplitude is determined at each frequency and the time constant determined by curve fitting. The resultant measured time constant is 130 12 s, in good agreement with the predicted value.

  7. Near infrared bioluminescence resonance energy transfer from firefly luciferase—quantum dot bionanoconjugates

    The bioluminescence resonance energy transfer (BRET) between firefly luciferase enzymes and semiconductive quantum dots (QDs) with near infrared emission is described. The QD were phase transferred to aqueous buffers using a histidine mediated phase transfer route, and incubated with a hexahistidine tagged, green emitting variant of firefly luciferase from Photinus pyralis (PPyGRTS). The PPyGRTS were bound to the QD interface via the hexahistidine tag, which effectively displaces the histidine layer and binds directly to the QD interfaces, allowing for short donor–acceptor distances (∼5.5 nm). Due to this, high BRET efficiency ratios of ∼5 were obtained. These PPyGRTS-QD bio-nano conjugates were characterized by transmission electron microscopy, thermal gravimetric analysis, Fourier transform infrared spectroscopy and BRET emission studies. The final optimized conjugate was easily observable by night vision imaging, demonstrating the potential of these materials in imaging and signaling/sensing applications. (paper)

  8. Near infrared bioluminescence resonance energy transfer from firefly luciferase—quantum dot bionanoconjugates

    Alam, Rabeka; Karam, Liliana M.; Doane, Tennyson L.; Zylstra, Joshua; Fontaine, Danielle M.; Branchini, Bruce R.; Maye, Mathew M.

    2014-12-01

    The bioluminescence resonance energy transfer (BRET) between firefly luciferase enzymes and semiconductive quantum dots (QDs) with near infrared emission is described. The QD were phase transferred to aqueous buffers using a histidine mediated phase transfer route, and incubated with a hexahistidine tagged, green emitting variant of firefly luciferase from Photinus pyralis (PPyGRTS). The PPyGRTS were bound to the QD interface via the hexahistidine tag, which effectively displaces the histidine layer and binds directly to the QD interfaces, allowing for short donor-acceptor distances (˜5.5 nm). Due to this, high BRET efficiency ratios of ˜5 were obtained. These PPyGRTS-QD bio-nano conjugates were characterized by transmission electron microscopy, thermal gravimetric analysis, Fourier transform infrared spectroscopy and BRET emission studies. The final optimized conjugate was easily observable by night vision imaging, demonstrating the potential of these materials in imaging and signaling/sensing applications.

  9. Imaging gene expression in real-time using aptamers

    Shin, Il Chung

    2011-12-13

    Signal transduction pathways are usually activated by external stimuli and are transient. The downstream changes such as transcription of the activated genes are also transient. Real-time detection of promoter activity is useful for understanding changes in gene expression, especially during cell differentiation and in development. A simple and reliable method for viewing gene expression in real time is not yet available. Reporter proteins such as fluorescent proteins and luciferase allow for non-invasive detection of the products of gene expression in living cells. However, current reporter systems do not provide for real-time imaging of promoter activity in living cells. This is because of the long time period after transcription required for fluorescent protein synthesis and maturation. We have developed an RNA reporter system for imaging in real-time to detect changes in promoter activity as they occur. The RNA reporter uses strings of RNA aptamers that constitute IMAGEtags (Intracellular MultiAptamer GEnetic tags), which can be expressed from a promoter of choice. The tobramycin, neomycin and PDC RNA aptamers have been utilized for this system and expressed in yeast from the GAL1 promoter. The IMAGEtag RNA kinetics were quantified by RT-qPCR. In yeast precultured in raffinose containing media the GAL1 promoter responded faster than in yeast precultured in glucose containing media. IMAGEtag RNA has relatively short half-life (5.5 min) in yeast. For imaging, the yeast cells are incubated with their ligands that are labeled with fluorescent dyes. To increase signal to noise, ligands have been separately conjugated with the FRET (Förster resonance energy transfer) pairs, Cy3 and Cy5. With these constructs, the transcribed aptamers can be imaged after activation of the promoter by galactose. FRET was confirmed with three different approaches, which were sensitized emission, acceptor photobleaching and donor lifetime by FLIM (fluorescence lifetime imaging microscopy). Real-time transcription was measured by FLIM-FRET, which was detected by the decrease in donor lifetime resulting from ligand binding to IMAGEtags that were newly synthesized from the activated GAL1 promoter. The FRET signal was specific for transcribed IMAGEtags.

  10. Real-Time Magnetic Resonance Imaging of Temporomandibular Joint Dynamics

    Zhang, Shuo; Gersdorff, Nikolaus; Frahm, Jens

    2011-01-01

    This study evaluated the use of a novel real-time MRI technique based on fast low angle shot (FLASH) MRI with radial encoding, gridding reconstruction, and sliding window for the assessment of temporomandibular joint (TMJ) dynamics in a cohort of 30 young volunteers without prior diagnosis of TMJ pathology. High-resolution images (0.75 0.75 mm2, 5 mm section thickness) were obtained at 3 frames per second for active jaw movements without adjunctive devices. Real-time movies were...

  11. Integration of image exposure time into a modified laser speckle imaging method

    Speckle-based methods have been developed to characterize tissue blood flow and perfusion. One such method, called modified laser speckle imaging (mLSI), enables computation of blood flow maps with relatively high spatial resolution. Although it is known that the sensitivity and noise in LSI measurements depend on image exposure time, a fundamental disadvantage of mLSI is that it does not take into account this parameter. In this work, we integrate the exposure time into the mLSI method and provide experimental support of our approach with measurements from an in vitro flow phantom.

  12. Integrated CMOS photodetectors and signal processing for very low-level chemical sensing with the bioluminescent bioreporter integrated circuit

    Bolton, Eric K.; Sayler, Gary S.; Nivens, David E.; Rochelle, James M.; Ripp, Steven; Simpson, Michael L.

    2002-01-01

    We report an integrated CMOS microluminometer optimized for the detection of low-level bioluminescence as part of the bioluminescent bioreporter integrated circuit (BBIC). This microluminometer improves on previous devices through careful management of the sub-femtoampere currents, both signal and leakage, that flow in the front-end processing circuitry. In particular, the photodiode is operated with a reverse bias of only a few mV, requiring special attention to the reset circuitry of the current-to-frequency converter (CFC) that forms the front-end circuit. We report a sub-femtoampere leakage current and a minimum detectable signal (MDS) of 0.15 fA (1510 s integration time) using a room temperature 1.47 mm2 CMOS photodiode. This microluminometer can detect luminescence from as few as 5000 fully induced Pseudomonas fluorescens 5RL bacterial cells. c2002 Elsevier Science B.V. All rights reserved.

  13. Real-time Imaging Orientation Determination System to Verify Imaging Polarization Navigation Algorithm.

    Lu, Hao; Zhao, Kaichun; Wang, Xiaochu; You, Zheng; Huang, Kaoli

    2016-01-01

    Bio-inspired imaging polarization navigation which can provide navigation information and is capable of sensing polarization information has advantages of high-precision and anti-interference over polarization navigation sensors that use photodiodes. Although all types of imaging polarimeters exist, they may not qualify for the research on the imaging polarization navigation algorithm. To verify the algorithm, a real-time imaging orientation determination system was designed and implemented. Essential calibration procedures for the type of system that contained camera parameter calibration and the inconsistency of complementary metal oxide semiconductor calibration were discussed, designed, and implemented. Calibration results were used to undistort and rectify the multi-camera system. An orientation determination experiment was conducted. The results indicated that the system could acquire and compute the polarized skylight images throughout the calibrations and resolve orientation by the algorithm to verify in real-time. An orientation determination algorithm based on image processing was tested on the system. The performance and properties of the algorithm were evaluated. The rate of the algorithm was over 1 Hz, the error was over 0.313°, and the population standard deviation was 0.148° without any data filter. PMID:26805851

  14. Validation of constitutively expressed bioluminescent Pseudomonas aeruginosa as a rapid microbiological quantification tool.

    Shah, N; Naseby, D C

    2015-06-15

    Whole cell biosensors have been extensively used for monitoring toxicity and contamination of various compounds and xenobiotics in environmental biology and microbial ecology; their application in the pharmaceutical and cosmetics industries has been limited. According to several pharmacopoeias, pharmaceutical products must be tested for microbial activity using traditional viable count techniques; the use of whole cell microbial biosensors potentially provides an alternative, fast, and efficient method. However there is a lack of a validated bioluminescence method. Prototype whole cell microbial biosensors have already been developed in Pseudomonas aeruginosa ATCC 9027. Validation of the bioluminescent strains was performed in accordance with the pharmacopoeia, Parenteral Drug Association and International Organisation of Standardisation. These strains demonstrated that the bioluminescent method was accurate, precise and equivalent, as compared with plate counting at a range of 10(3)-10(7) CFU/mL. Percentage recoveries using the bioluminescent method were between 70% and 130% for all bioluminescent strains and therefore the bioluminescent method was accurate according to the criteria set in PDA technical report 33. The method was also more precise (relative standard deviation less than 15%) than the traditional plate counting method or the ATP bioluminescent method. The lower limit of detection was 10(3) CFU/mL. Two-way ANOVA showed no significant difference between the traditional plate counting and the novel bioluminescent method for all bioluminescent strains. The bioluminescent constructs passed/exceeded pharmacopoeia-specified criteria for range, limit of detection, accuracy, precision and equivalence. PMID:25618377

  15. BLProt: Prediction of bioluminescent proteins based on support vector machine and relieff feature selection

    Kandaswamy, Krishna Kumar

    2011-08-17

    Background: Bioluminescence is a process in which light is emitted by a living organism. Most creatures that emit light are sea creatures, but some insects, plants, fungi etc, also emit light. The biotechnological application of bioluminescence has become routine and is considered essential for many medical and general technological advances. Identification of bioluminescent proteins is more challenging due to their poor similarity in sequence. So far, no specific method has been reported to identify bioluminescent proteins from primary sequence.Results: In this paper, we propose a novel predictive method that uses a Support Vector Machine (SVM) and physicochemical properties to predict bioluminescent proteins. BLProt was trained using a dataset consisting of 300 bioluminescent proteins and 300 non-bioluminescent proteins, and evaluated by an independent set of 141 bioluminescent proteins and 18202 non-bioluminescent proteins. To identify the most prominent features, we carried out feature selection with three different filter approaches, ReliefF, infogain, and mRMR. We selected five different feature subsets by decreasing the number of features, and the performance of each feature subset was evaluated.Conclusion: BLProt achieves 80% accuracy from training (5 fold cross-validations) and 80.06% accuracy from testing. The performance of BLProt was compared with BLAST and HMM. High prediction accuracy and successful prediction of hypothetical proteins suggests that BLProt can be a useful approach to identify bioluminescent proteins from sequence information, irrespective of their sequence similarity. 2011 Kandaswamy et al; licensee BioMed Central Ltd.

  16. Real-time color image processing for forensic fiber investigations

    Paulsson, Nils

    1995-09-01

    This paper describes a system for automatic fiber debris detection based on color identification. The properties of the system are fast analysis and high selectivity, a necessity when analyzing forensic fiber samples. An ordinary investigation separates the material into well above 100,000 video images to analyze. The system is based on standard techniques such as CCD-camera, motorized sample table, and IBM-compatible PC/AT with add-on-boards for video frame digitalization and stepping motor control as the main parts. It is possible to operate the instrument at full video rate (25 image/s) with aid of the HSI-color system (hue- saturation-intensity) and software optimization. High selectivity is achieved by separating the analysis into several steps. The first step is fast direct color identification of objects in the analyzed video images and the second step analyzes detected objects with a more complex and time consuming stage of the investigation to identify single fiber fragments for subsequent analysis with more selective techniques.

  17. Precision cosmology with time delay lenses: high resolution imaging requirements

    Meng, Xiao-Lei; Treu, Tommaso; Agnello, Adriano; Auger, Matthew W.; Liao, Kai; Marshall, Philip J.

    2015-09-01

    Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host galaxies of lensed quasars, which appear as ``Einstein Rings'' in high resolution images. The distortion of these arcs and counter-arcs, as measured over a large number of pixels, provides tight constraints on the difference between the gravitational potential between the quasar image positions, and thus on cosmology in combination with the measured time delay. We carry out a systematic exploration of the high resolution imaging required to exploit the thousands of lensed quasars that will be discovered by current and upcoming surveys with the next decade. Specifically, we simulate realistic lens systems as imaged by the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and ground based adaptive optics images taken with Keck or the Thirty Meter Telescope (TMT). We compare the performance of these pointed observations with that of images taken by the Euclid (VIS), Wide-Field Infrared Survey Telescope (WFIRST) and Large Synoptic Survey Telescope (LSST) surveys. We use as our metric the precision with which the slope γ' of the total mass density profile ρtotpropto r-γ' for the main deflector can be measured. Ideally, we require that the statistical error on γ' be less than 0.02, such that it is subdominant to other sources of random and systematic uncertainties. We find that survey data will likely have sufficient depth and resolution to meet the target only for the brighter gravitational lens systems, comparable to those discovered by the SDSS survey. For fainter systems, that will be discovered by current and future surveys, targeted follow-up will be required. However, the exposure time required with upcoming facilitites such as JWST, the Keck Next Generation Adaptive Optics System, and TMT, will only be of order a few minutes per system, thus making the follow-up of hundreds of systems a practical and efficient cosmological probe.

  18. Real time blood testing using quantitative phase imaging.

    Pham, Hoa V; Bhaduri, Basanta; Tangella, Krishnarao; Best-Popescu, Catherine; Popescu, Gabriel

    2013-01-01

    We demonstrate a real-time blood testing system that can provide remote diagnosis with minimal human intervention in economically challenged areas. Our instrument combines novel advances in label-free optical imaging with parallel computing. Specifically, we use quantitative phase imaging for extracting red blood cell morphology with nanoscale sensitivity and NVIDIA's CUDA programming language to perform real time cellular-level analysis. While the blood smear is translated through focus, our system is able to segment and analyze all the cells in the one megapixel field of view, at a rate of 40 frames/s. The variety of diagnostic parameters measured from each cell (e.g., surface area, sphericity, and minimum cylindrical diameter) are currently not available with current state of the art clinical instruments. In addition, we show that our instrument correctly recovers the red blood cell volume distribution, as evidenced by the excellent agreement with the cell counter results obtained on normal patients and those with microcytic and macrocytic anemia. The final data outputted by our instrument represent arrays of numbers associated with these morphological parameters and not images. Thus, the memory necessary to store these data is of the order of kilobytes, which allows for their remote transmission via, for example, the cellular network. We envision that such a system will dramatically increase access for blood testing and furthermore, may pave the way to digital hematology. PMID:23405194

  19. High-temperature real-time ultrasonic imaging

    Ultrasonic instrumentation capable of real-time imaging of materials at temperatures up to 2880C (5900F) is described. The research and development of this unique instrumentation was sponsored by the Electric Power Research Institute of Palo Alto, California, for use in nuclear power plants. The instrumentation developed will permit continuous surveillance of piping while the power plant is in operation. The instrumentation utilizes a combination of high-temperature materials to fabricate a unique piezoelectric transmitter and a high-temperature electromagnetic acoustic transducer (EMAT). The high-temperature EMAT operates at 2.5 MHz, which is well above preceding models of about 800 kHz. Use of unique high-temperature materials to permit scanning of material volume is combined with an imaging system to allow time-lapse image information. This paper traces the theory and describes material properties of interest and reports on test results for a development system that has been in continuous operation on a field test site for two years. Future applications and development plans are outlined

  20. Real-time Image Generation for Compressive Light Field Displays

    Wetzstein, G.; Lanman, D.; Hirsch, M.; Raskar, R.

    2013-02-01

    With the invention of integral imaging and parallax barriers in the beginning of the 20th century, glasses-free 3D displays have become feasible. Only todaymore than a century laterglasses-free 3D displays are finally emerging in the consumer market. The technologies being employed in current-generation devices, however, are fundamentally the same as what was invented 100 years ago. With rapid advances in optical fabrication, digital processing power, and computational perception, a new generation of display technology is emerging: compressive displays exploring the co-design of optical elements and computational processing while taking particular characteristics of the human visual system into account. In this paper, we discuss real-time implementation strategies for emerging compressive light field displays. We consider displays composed of multiple stacked layers of light-attenuating or polarization-rotating layers, such as LCDs. The involved image generation requires iterative tomographic image synthesis. We demonstrate that, for the case of light field display, computed tomographic light field synthesis maps well to operations included in the standard graphics pipeline, facilitating efficient GPU-based implementations with real-time framerates.

  1. Real-time Image Generation for Compressive Light Field Displays

    With the invention of integral imaging and parallax barriers in the beginning of the 20th century, glasses-free 3D displays have become feasible. Only today—more than a century later—glasses-free 3D displays are finally emerging in the consumer market. The technologies being employed in current-generation devices, however, are fundamentally the same as what was invented 100 years ago. With rapid advances in optical fabrication, digital processing power, and computational perception, a new generation of display technology is emerging: compressive displays exploring the co-design of optical elements and computational processing while taking particular characteristics of the human visual system into account. In this paper, we discuss real-time implementation strategies for emerging compressive light field displays. We consider displays composed of multiple stacked layers of light-attenuating or polarization-rotating layers, such as LCDs. The involved image generation requires iterative tomographic image synthesis. We demonstrate that, for the case of light field display, computed tomographic light field synthesis maps well to operations included in the standard graphics pipeline, facilitating efficient GPU-based implementations with real-time framerates.

  2. Time-resolved spectral imaging: better photon economy, higher accuracy

    Fereidouni, Farzad; Reitsma, Keimpe; Blab, Gerhard A.; Gerritsen, Hans C.

    2015-03-01

    Lifetime and spectral imaging are complementary techniques that offer a non-invasive solution for monitoring metabolic processes, identifying biochemical compounds, and characterizing their interactions in biological tissues, among other tasks. Newly developed instruments that perform time-resolved spectral imaging can provide even more information and reach higher sensitivity than either modality alone. Here we report a multispectral lifetime imaging system based on a field-programmable gate array (FPGA), capable of operating at high photon count rates (12 MHz) per spectral detection channel, and with time resolution of 200 ps. We performed error analyses to investigate the effect of gate width and spectral-channel width on the accuracy of estimated lifetimes and spectral widths. Temporal and spectral phasors were used for analysis of recorded data, and we demonstrated blind un-mixing of the fluorescent components using information from both modalities. Fractional intensities, spectra, and decay curves of components were extracted without need for prior information. We further tested this approach with fluorescently doubly-labeled DNA, and demonstrated its suitability for accurately estimating FRET efficiency in the presence of either non-interacting or interacting donor molecules.

  3. A portable, real-time, holographic system for imaging flaws

    In this paper the authors describe a portable system that can be used in a field situation. Image reconstruction is accomplished mathematically in near real-time, and the image displayed in a variety of formats. The system utilizes a special purpose microcomputer designed around the 16-bit Intel 8086 and 8087 microprocessor chips. The system fits into three suitcase containers that can be shipped as excess baggage on most air-lines. The system has been tested on pressure vessel and piping samples containing machined and natural flaws, and has also been used in the field to inspect a weld in the steam generator shell of a nuclear power plant. The theory, implementation, and experimental results are presented

  4. Results from the Allen Telescope Array: Real-Time Imaging

    Keating, Garrett; Barott, J.; Allen Telescope Array Team

    2009-12-01

    We present current results from the Automated Real-Time Imaging System (ARTIS), a software system that allows for rapid reduction of interferometer data at the Allen Telescope Array (ATA). ARTIS supports automated processing for both continuum and spectral line observations, and is capable of supporting wide-field surveys. Motivation for this system arises from both the volume of data produced at the ATA and the need for timely results from observations. The ATA is capable of producing hundreds of gigabytes of data, and covering thousands of square degrees of the sky in a single day. The ATA has also embarked upon several surveys searching for transient events, making quick and reliable automated analysis essential for scientific work. ARTIS (and its affiliated software) has been used for a number of large-scale observations, including transient, HI and maser surveys. ARTIS is also producing real-time data quality measurements for observations, allowing for more robust observing.

  5. GPU acceleration of time-domain fluorescence lifetime imaging

    Wu, Gang; Nowotny, Thomas; Chen, Yu; Li, David Day-Uei

    2016-01-01

    Fluorescence lifetime imaging microscopy (FLIM) plays a significant role in biological sciences, chemistry, and medical research. We propose a graphic processing unit (GPU) based FLIM analysis tool suitable for high-speed, flexible time-domain FLIM applications. With a large number of parallel processors, GPUs can significantly speed up lifetime calculations compared to CPU-OpenMP (parallel computing with multiple CPU cores) based analysis. We demonstrate how to implement and optimize FLIM algorithms on GPUs for both iterative and noniterative FLIM analysis algorithms. The implemented algorithms have been tested on both synthesized and experimental FLIM data. The results show that at the same precision, the GPU analysis can be up to 24-fold faster than its CPU-OpenMP counterpart. This means that even for high-precision but time-consuming iterative FLIM algorithms, GPUs enable fast or even real-time analysis.

  6. Time-resolved neutron imaging at ANTARES cold neutron beamline

    Tremsin, A. S.; Dangendorf, V.; Tittelmeier, K.; Schillinger, B.; Schulz, M.; Lerche, M.; Feller, W. B.

    2015-07-01

    In non-destructive evaluation with X-rays light elements embedded in dense, heavy (or high-Z) matrices show little contrast and their structural details can hardly be revealed. Neutron radiography, on the other hand, provides a solution for those cases, in particular for hydrogenous materials, owing to the large neutron scattering cross section of hydrogen and uncorrelated dependency of neutron cross section on the atomic number. The majority of neutron imaging experiments at the present time is conducted with static objects mainly due to the limited flux intensity of neutron beamline facilities and sometimes due to the limitations of the detectors. However, some applications require the studies of dynamic phenomena and can now be conducted at several high intensity beamlines such as the recently rebuilt ANTARES beam line at the FRM-II reactor. In this paper we demonstrate the capabilities of time resolved imaging for repetitive processes, where different phases of the process can be imaged simultaneously and integrated over multiple cycles. A fast MCP/Timepix neutron counting detector was used to image the water distribution within a model steam engine operating at 10 Hz frequency. Within cycle time with a sub-mm spatial resolution, thereby demonstrating the capabilities of time-resolved neutron radiography for the future applications. The neutron spectrum of the ANTARES beamline as well as transmission spectra of a Fe sample were also measured with the Time Of Flight (TOF) technique in combination with a high resolution beam chopper. The energy resolution of our setup was found to be ~ 0.8% at 5 meV and ~ 1.7% at 25 meV. The background level (most likely gammas and epithermal/fast neutrons) of the ANTARES beamline was also measured in our experiments and found to be on the scale of 3% when no filters are installed in the beam. Online supplementary data available from stacks.iop.org/jinst/10/P07008/mmedia. The videos are given as supplementary material linked to the main article.

  7. Satellite image time series simulation for environmental monitoring

    Guo, Tao

    2014-11-01

    The performance of environmental monitoring heavily depends on the availability of consecutive observation data and it turns out an increasing demand in remote sensing community for satellite image data in the sufficient resolution with respect to both spatial and temporal requirements, which appear to be conflictive and hard to tune tradeoffs. Multiple constellations could be a solution if without concerning cost, and thus it is so far interesting but very challenging to develop a method which can simultaneously improve both spatial and temporal details. There are some research efforts to deal with the problem from various aspects, a type of approaches is to enhance the spatial resolution using techniques of super resolution, pan-sharpen etc. which can produce good visual effects, but mostly cannot preserve spectral signatures and result in losing analytical value. Another type is to fill temporal frequency gaps by adopting time interpolation, which actually doesn't increase informative context at all. In this paper we presented a novel method to generate satellite images in higher spatial and temporal details, which further enables satellite image time series simulation. Our method starts with a pair of high-low resolution data set, and then a spatial registration is done by introducing LDA model to map high and low resolution pixels correspondingly. Afterwards, temporal change information is captured through a comparison of low resolution time series data, and the temporal change is then projected onto high resolution data plane and assigned to each high resolution pixel referring the predefined temporal change patterns of each type of ground objects to generate a simulated high resolution data. A preliminary experiment shows that our method can simulate a high resolution data with a good accuracy. We consider the contribution of our method is to enable timely monitoring of temporal changes through analysis of low resolution images time series only, and usage of costly high resolution data can be reduced as much as possible, and it presents an efficient solution with great cost performance to build up an economically operational monitoring service for environment, agriculture, forest, land use investigation, and other applications.

  8. Real-time underwater image enhancement: An improved approach for imaging with AUV-150

    Jeet Banerjee; Ranjit Ray; Siva Ram Krishna Vadali; Sankar Nath Shome; Sambhunath Nandy

    2016-02-01

    An RGB YCbCr Processing method (RYPro) is proposed for underwater images commonly suffering from low contrast and poor color quality. The degradation in image quality may be attributed to absorption and backscattering of light by suspended underwater particles. Moreover, as the depth increases, different colors are absorbed by the surrounding medium depending on the wavelengths. In particular, blue/green color is dominant in the underwater ambience which is known as color cast. For further processing of the image, enhancement remains an essential preprocessing operation. Color equalization is a widely adopted approach for underwater image enhancement. Traditional methods normally involve blind color equalization for enhancing the image under test. In the present work, processing sequence of the proposed method includes noise removal using linear and non-linear filters followed by adaptive contrast correction in the RGB and YCbCr color planes. Performance of the proposed method is evaluated and compared with three golden methods, namely, Gray World (GW), White Patch (WP), Adobe Photoshop Equalization (APE) and a recently developed method entitled “Unsupervised Color Correction Method (UCM)”. In view of its simplicity and computational ease, the proposed method is recommended for real-time applications. Suitability of the proposed method is validated by real-time implementation during the testing of the Autonomous Underwater Vehicle (AUV-150) developed indigenously by CSIR-CMERI.

  9. Modelling dinoflagellates as an approach to the seasonal forecasting of bioluminescence in the North Atlantic

    Marcinko, Charlotte L. J.; Martin, Adrian P.; Allen, John T.

    2014-11-01

    Bioluminescence within ocean surface waters is of significant interest because it can enhance the study of subsurface movement and organisms. Little is known about how bioluminescence potential (BPOT) varies spatially and temporally in the open ocean. However, light emitted from dinoflagellates often dominates the stimulated bioluminescence field. As a first step towards forecasting surface ocean bioluminescence in the open ocean, a simple ecological model is developed which simulates seasonal changes in dinoflagellate abundance. How forecasting seasonal changes in BPOT may be achieved through combining such a model with relationships derived from observations is discussed and an example is given. The study illustrates a potential new approach to forecasting BPOT through explicitly modelling the population dynamics of a prolific bioluminescent phylum. The model developed here offers a promising platform for the future operational forecasting of the broad temporal changes in bioluminescence within the North Atlantic. Such forecasting of seasonal patterns could provide valuable information for the targeting of scientific field campaigns.

  10. NanoLuc Reporter for Dual Luciferase Imaging in Living Animals

    Stacer, Amanda C.; Nyati, Shyam; Moudgil, Pranav; Iyengar, Rahul; Kathryn E. Luker; Rehemtulla, Alnawaz; Luker, Gary D.

    2013-01-01

    Bioluminescence imaging is utilized widely for cell-based assays and animal imaging studies in biomedical research and drug development, capitalizing on high signal-to-background of this technique. A relatively small number of luciferases are available for imaging studies, substantially limiting the ability to image multiple molecular and cellular events as done commonly with fluorescence imaging. To advance dual reporter bioluminescence molecular imaging, we tested a recently developed, ATP-...

  11. A study on bioluminescence and photoluminescence in the earthworm Eisenia lucens.

    Pes, O; Midlik, A; Schlaghamersky, J; Zitnan, M; Taborsky, P

    2016-02-10

    Eisenia lucens is an earthworm living in the organic soil layer of decomposing wood. When irritated, the worm expels coelomic fluid through pores in its body wall, exhibiting blue-green bioluminescence. The mechanism of the bioluminescence, which seems to be different from other bioluminescence systems of terrestrial animals, has been studied in this work. Many lines of evidence indicate that riboflavin stored in coelomycetes plays an important role in this glowing reaction. PMID:26786938

  12. HOMOGENEOUS MULTISTAGE ARCHITECTURE FOR REAL-TIME IMAGE PROCESSING

    Hanen Chenini

    2012-12-01

    Full Text Available In this article, we present a new multistage architecture oriented to real-time complex processing applications. Given a set of rules, this proposed architecture allows the using of different communication links (point to point link, hardware router… to connect unlimited number of parallel computing elements (software processors to follow the increasing complexity of algorithms. In particular, this work brings out a parallel implementation of multihypothesis approach for road recognition application on the proposed Multiprocessor Systemon-Chip (MP-SoC architecture. This algorithm is usually the main part of the lane keeping applications. Experimental results using images of a real road scene are presented. Using a low cost FPGA-based System-on-Chip, our hardware architecture is able to detect and recognize the roadsides in a time limit of 60 mSec. Moreover, we demonstrate that our multistage architecture may be used to achieve good speed-up in solving automotive applications.

  13. Bioluminescence for USP sterility testing of pharmaceutical suspension products.

    Bussey, D M; K. Tsuji

    1986-01-01

    Bioluminescence measurement significantly improved the accuracy, sensitivity, precision, and reliability of the current visual endpoint determination for the USP sterility test and eliminated the day 7 transfer/dilution step required for testing suspension products. Thirteen strains of bacteria and fungi (representing potential contaminants in sterile products), three pharmaceutical suspension products, and four media were used in the experiment. No interference from suspension products was e...

  14. Bioluminescence determination of active caspase-3 in single apoptotic cells

    Lišková, Marcela; Klepárník, Karel; Matalová, Eva; Hegrová, Jitka; Přikryl, Jan; Švandová, Eva; Foret, František

    2013-01-01

    Roč. 34, č. 12 (2013), s. 1772-1777. ISSN 0173-0835 R&D Projects: GA ČR GAP206/11/2377 Grant ostatní: GA ČR(CZ) GAP502/12/1285 Institutional support: RVO:68081715 ; RVO:67985904 Keywords : apoptosis * bioluminescence * caspase-3 Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.161, year: 2013

  15. A Novel Bioluminescent Protease Assay Using Engineered Firefly Luciferase

    Wigdal, Susan S.; Anderson, Jessica L; Vidugiris, Gediminas J; Shultz, John; Wood, Keith V.; Fan, Frank

    2008-01-01

    Proteases play important roles in a variety of disease processes. Understanding their biological functions underpins the efforts of drug discovery. We have developed a bioluminescent protease assay using a circularly permuted form of firefly luciferase, wherein the native enzyme termini were joined by a peptide containing a protease site of interest. Protease cleavage of these mutant luciferases greatly activates the enzyme, typically over 100 fold. The mutant luciferase substrates are easily...

  16. Bioluminescent bacteria as indicators of chemical contamination of coastal waters.

    Frischer, M E; Danforth, J M; Foy, T F; Juraske, R

    2005-01-01

    The ratio of bioluminescent to total bacteria (bioluminescent ratio, BLR) as an indicator of a variety of types of anthropogenic contamination of estuarine ecosystems was evaluated through a series of laboratory and field studies. Laboratory studies indicated that the BLR of natural bacterioplankton communities was proportionally reduced in the presence of a number of contaminants including diesel fuel and saltmarsh sediments co-contaminated with mercury and polychlorinated biphenyls (PCBs). Bioluminescent ratio inhibition was observed after short-term exposure to a contaminant suggesting a physiological rather than a population response of native microbial communities. Simulated eutrophication did not suppress the BLR. Field observations of the BLR were conducted weekly for a 2-yr period in the Skidaway River estuary, Georgia, USA. These observations revealed considerable seasonal variability associated with the BLR. Bioluminescent ratios were highest during the summer (25 +/- 15%), lower in the fall (6 +/- 5%) and spring (3 +/- 2%), and near zero during the winter. Although the BLR was not significantly correlated to salinity at a single site (Skidaway River estuary), the BLR was significantly correlated with salinity when sites within the same estuary system were compared (r2 = 0.93). Variation in BLR was not correlated to standard bacteriological indicators of water quality including total and fecal coliform bacteria. Comparison of the BLR from impacted and pristine estuarine sites during the fall suggested that anthropogenically impacted sites exhibited lower BLR than predicted from salinity versus BLR relationships developed in pristine systems. These observations suggest that the BLR could be used as a simple and reliable initial indicator of chemical contamination of estuarine systems resulting from human activity. PMID:15998855

  17. Advanced Imaging by Space-Time Deconvolution in Array GPR

    Savelyev, T. G.; van Tol, N. T.; Yarovoy, A. G.; Ligthart, L. P.

    Digital beamforming in array-based UWB radar delivers a high-resolution 3-D image of subsurface in GPR landmine detection while simultaneous data acquisition by elements of the array significantly increases the scanning speed. Such a GPR system with a single transmit antenna and a linear receive array has been developed in the Delft University of Technology. For online processing we propose an advanced imaging algorithm based on migration by regularized, parametric space-time deconvolution. The algorithm deconvolves a 3-D space-time array point spread function out of the data volume by means of FFT and inverse Wiener filter that is being controlled automatically with numerical criteria for stability and accuracy. The prior knowledge of GPR impulse response and ground impulse response is used to form a separate point spread function for each receiving antenna. The developed technique has been verified on experimental data for typical anti-personnel mines and compared with a classical migration by diffraction stacking.

  18. Satellite Image Time Series Decomposition Based on EEMD

    Yun-long Kong

    2015-11-01

    Full Text Available Satellite Image Time Series (SITS have recently been of great interest due to the emerging remote sensing capabilities for Earth observation. Trend and seasonal components are two crucial elements of SITS. In this paper, a novel framework of SITS decomposition based on Ensemble Empirical Mode Decomposition (EEMD is proposed. EEMD is achieved by sifting an ensemble of adaptive orthogonal components called Intrinsic Mode Functions (IMFs. EEMD is noise-assisted and overcomes the drawback of mode mixing in conventional Empirical Mode Decomposition (EMD. Inspired by these advantages, the aim of this work is to employ EEMD to decompose SITS into IMFs and to choose relevant IMFs for the separation of seasonal and trend components. In a series of simulations, IMFs extracted by EEMD achieved a clear representation with physical meaning. The experimental results of 16-day compositions of Moderate Resolution Imaging Spectroradiometer (MODIS, Normalized Difference Vegetation Index (NDVI, and Global Environment Monitoring Index (GEMI time series with disturbance illustrated the effectiveness and stability of the proposed approach to monitoring tasks, such as applications for the detection of abrupt changes.

  19. Using Opaque Image Blur for Real-Time Depth-of-Field Rendering and Image-Based Motion Blur

    Kraus, Martin

    While depth of field is an important cinematographic means, its use in real-time computer graphics is still limited by the computational costs that are necessary to achieve a sufficient image quality. Specifically, color bleeding artifacts between objects at different depths are most effectively...... that the opaque image blur can also be used to add motion blur effects to images in real time....

  20. Seasonal variation of deep-sea bioluminescence in the Ionian Sea

    The ICDeep (Image Intensified Charge Coupled Device for Deep sea research) profiler was used to measure the density of deep bioluminescent animals (BL) through the water column in the east, west and mid-Ionian Sea and in the Algerian Basin. A west to east decrease in BL density was found. Generalized additive modelling was used to investigate seasonal variation in the east and west Ionian Sea (NESTOR and NEMO neutrino telescope sites, respectively) from BL measurements in autumn 2008 and spring 2009. A significant seasonal effect was found in the west Ionian Sea (p<0.001), where a deep autumnal peak in BL density occurred between 500 and 2400 m. No significant seasonal variation in BL density was found in the east Ionian Sea (p=0.07). In both spring and autumn, significant differences in BL density were found through the water column between the east and west Ionian Sea (p<0.001).

  1. Visible light induced ocular delayed bioluminescence as a possible origin of negative afterimage

    Bokkon, I; Wang, C; Dai, J; Salari, V; Grass, F; Antal, I

    2011-01-01

    The delayed luminescence of biological tissues is an ultraweak reemission of absorbed photons after exposure to external monochromatic or white light illumination. Recently, Wang, B\\'okkon, Dai and Antal (Brain Res. 2011) presented the first experimental proof of the existence of spontaneous ultraweak biophoton emission and visible light induced delayed ultraweak photon emission from in vitro freshly isolated rat's whole eye, lens, vitreous humor and retina. Here, we suggest that the photobiophysical source of negative afterimage can also occur within the eye by delayed bioluminescent photons. In other words, when we stare at a colored (or white) image for few seconds, external photons can induce excited electronic states within different parts of the eye that is followed by a delayed reemission of absorbed photons for several seconds. Finally, these reemitted photons can be absorbed by nonbleached photoreceptors that produce a negative afterimage. Although this suggests the photobiophysical source of negativ...

  2. Seasonal variation of deep-sea bioluminescence in the Ionian Sea

    Craig, Jessica, E-mail: j.craig@abdn.ac.u [University of Aberdeen, Oceanlab, Main Street, Newburgh, Aberdeenshire, AB41 6AA (United Kingdom); Jamieson, Alan J.; Bagley, Philip M.; Priede, Imants G. [University of Aberdeen, Oceanlab, Main Street, Newburgh, Aberdeenshire, AB41 6AA (United Kingdom)

    2011-01-21

    The ICDeep (Image Intensified Charge Coupled Device for Deep sea research) profiler was used to measure the density of deep bioluminescent animals (BL) through the water column in the east, west and mid-Ionian Sea and in the Algerian Basin. A west to east decrease in BL density was found. Generalized additive modelling was used to investigate seasonal variation in the east and west Ionian Sea (NESTOR and NEMO neutrino telescope sites, respectively) from BL measurements in autumn 2008 and spring 2009. A significant seasonal effect was found in the west Ionian Sea (p<0.001), where a deep autumnal peak in BL density occurred between 500 and 2400 m. No significant seasonal variation in BL density was found in the east Ionian Sea (p=0.07). In both spring and autumn, significant differences in BL density were found through the water column between the east and west Ionian Sea (p<0.001).

  3. L1/2 regularization based numerical method for effective reconstruction of bioluminescence tomography

    Even though bioluminescence tomography (BLT) exhibits significant potential and wide applications in macroscopic imaging of small animals in vivo, the inverse reconstruction is still a tough problem that has plagued researchers in a related area. The ill-posedness of inverse reconstruction arises from insufficient measurements and modeling errors, so that the inverse reconstruction cannot be solved directly. In this study, an l1/2 regularization based numerical method was developed for effective reconstruction of BLT. In the method, the inverse reconstruction of BLT was constrained into an l1/2 regularization problem, and then the weighted interior-point algorithm (WIPA) was applied to solve the problem through transforming it into obtaining the solution of a series of l1 regularizers. The feasibility and effectiveness of the proposed method were demonstrated with numerical simulations on a digital mouse. Stability verification experiments further illustrated the robustness of the proposed method for different levels of Gaussian noise

  4. L1/2 regularization based numerical method for effective reconstruction of bioluminescence tomography

    Chen, Xueli; Yang, Defu; Zhang, Qitan; Liang, Jimin

    2014-05-01

    Even though bioluminescence tomography (BLT) exhibits significant potential and wide applications in macroscopic imaging of small animals in vivo, the inverse reconstruction is still a tough problem that has plagued researchers in a related area. The ill-posedness of inverse reconstruction arises from insufficient measurements and modeling errors, so that the inverse reconstruction cannot be solved directly. In this study, an l1/2 regularization based numerical method was developed for effective reconstruction of BLT. In the method, the inverse reconstruction of BLT was constrained into an l1/2 regularization problem, and then the weighted interior-point algorithm (WIPA) was applied to solve the problem through transforming it into obtaining the solution of a series of l1 regularizers. The feasibility and effectiveness of the proposed method were demonstrated with numerical simulations on a digital mouse. Stability verification experiments further illustrated the robustness of the proposed method for different levels of Gaussian noise.

  5. Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

    Peruzzini, D.; Viti, J.; Tortoli, P.; Verweij, M. D.; de Jong, N.; Vos, H. J.

    2015-10-01

    Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher harmonics, i.e. "superharmonic" imaging, shows better contrast. However, the superharmonic scattering has a lower signal level compared to e.g. second harmonic signals. This study investigates the contrast-to-tissue ratio (CTR) and signal to noise ratio (SNR) of superharmonic UCA scattering in a tissue/vessel mimicking phantom using a real-time clinical scanner. Numerical simulations were performed to estimate the level of harmonics generated by the microbubbles. Data were acquired with a custom built dual-frequency cardiac phased array probe. Fundamental real-time images were produced while beam formed radiofrequency (RF) data was stored for further offline processing. The phantom consisted of a cavity filled with UCA surrounded by tissue mimicking material. The acoustic pressure in the cavity of the phantom was 110 kPa (MI = 0.11) ensuring non-destructivity of UCA. After processing of the acquired data from the phantom, the UCA-filled cavity could be clearly observed in the images, while tissue signals were suppressed at or below the noise floor. The measured CTR values were 36 dB, >38 dB, and >32 dB, for the second, third, and fourth harmonic respectively, which were in agreement with those reported earlier for preliminary contrast superharmonic imaging. The single frame SNR values (in which `signal' denotes the signal level from the UCA area) were 23 dB, 18 dB, and 11 dB, respectively. This indicates that noise, and not the tissue signal, is the limiting factor for the UCA detection when using the superharmonics in nondestructive mode.

  6. Time Lapse Electrical Imaging of Salt Affected Soil and Groundwater

    Hayley, Kevin

    This research was conducted to test the hypothesis that time-lapse electrical resistivity imaging (ERI) could be used as an effective tool for monitoring remediation of salt affected soil and groundwater. A time-lapse 3D ERI survey conducted over the span of 3 years was used to observe changes in an oilfield brine plume undergoing remediation using a tile drainage network. A theoretical model was modified to incorporate the results of an electrical conductivity (EC) temperature laboratory experiment and a linear EC temperature relationship was calibrated for the 0--25°C range. Using the linear approximation and theoretical model observed temperature and saturation variations could be accounted for in bulk EC measurements. ERI inversion parameters were selected to produce a model with the best agreement with collocated push tool conductivity logs, and the strongest correlation with core salinity measurements. The ERI models were transformed into salinity estimates in order to produce salt concentration maps and salt removal estimates. A temperature correction method was developed that acted on the collected electrical resistivity data, rather than on the inversion model. A data correction was sought in order to remove the effect of inversion smoothing from the temperature correction and to compensate for temperature prior to inversion opening the possibility of using time-lapse inversion techniques. First the data were inverted to produce a model, and then the model was converted to a standard temperature equivalent model using the previously developed EC temperature relationship. The difference between synthetic datasets produced using the inversion model and the standard temperature equivalent model was used as a data temperature correction factor and applied to the collected data. A simultaneous time-lapse inversion method was developed and compared to previously published methods. The simultaneous approach consisted of inverting the time-lapse datasets together and adding constraints, updated at each iteration, that changes between the resulting models be smooth and close to a reference difference model. Application of the data temperature correction and simultaneous time-lapse inversion produced a simple easily interpretable time-lapse image. The observed EC decreases were consistent with the concept of depression focused recharge enhancing infiltration and remediation under a slight topography low.

  7. Abdominal MR imaging using a HASTE sequence : image comparison on the different echo times

    To determine the optimal parameters of abdominal HASTE imaging by means of a comparison of intermediate and long TE (echo time). We evaluated 30 consecutive patients who had undergone liver MR during a three-month period. Twelve patients were diagnosed as normal, four as having liver cirrhosis, and 14 were found to be suffering form hepatic hemangioma. On the basis of measured signal intensity of the liver, spleen, pancreas and gallbladder, and of fat, muscle, hemangioma, and background, we calculated the ratios of signal to noise (S/N), signal difference to noise (SD/N), and signal intensity (SI). Image quality was compared using these three ratios, and using two HASTE sequences with TEs of 90 msec and 134 msec, images were qualitatively evaluated. S/N ratio of the liver was higher when TE was 90 msec(p<.05), though S/N, SD/N and SI rations of the spleen, gallbladder, and pancreas-and of hemangiom-were higher when TE was 134 msec (p<.05). However, in muscle, all these three ratios were higher at a TE of 90 msec. SD/N ratio and SI of fat were higher at a TE of 134 msec. Overall image quality was better at a TE of 134 msec than at one of 90msec. A HASTE sequence with a TE of 134msec showed greater tissue contrast and stronger T2-weighted images than one with a TE of 90msec

  8. Radiofrequency transmission line for bioluminescent Vibrio sp. irradiation

    Nassisi, V.; Alifano, P.; Talà, A.; Velardi, L.

    2012-07-01

    We present the study and the analyses of a transmission line for radiofrequency (RF) irradiation of bacteria belonging to Vibrio harveyi-related strain PS1, a bioluminescent bacterium living in symbiosis with many marine organisms. The bioluminescence represents a new biologic indicator which is useful for studying the behaviour of living samples in the presence of RF waves due to the modern communication systems. A suitable transmission line, used as an irradiating cell and tested up to the maximum frequency used by the global system for mobile communications and universal mobile telecommunications system transmissions, was characterized. In this experiment, the RF voltage applied to the transmission line was 1 V. Due to short dimensions of the line and the applied high frequencies, standing waves were produced in addition to progressing waves and the electric field strength varies particularly along the longitudinal direction. The magnetic field map was not strongly linked to the electric one due to the presence of standing waves and of the outgoing irradiation. RF fields were measured by two homemade suitable probes able to diagnostic fields of high frequency. The field measurements were performed without any specimens inside the line. Being our sample made of living matter, the real field was modified and its value was estimated by a simulation code. The bioluminescence experiments were performed only at 900 MHz for two different measured electric fields, 53 and 140 V/m. The light emission was measured right from the beginning and after 7 and 25 h. Under RF irradiation, we found that the bioluminescence activity decreased. Compared with the control sample, the diminution was 6.8% and 44% after 7 and 25 h of irradiation, respectively, both with the low or high field. No changes of the survival factor for all the samples were observed. Besides, to understand the emission processes, we operated the deconvolution of the spectra by two Gaussian curves. The Gaussian peaks were approximately centered at 460 nm and 490 nm. The 490 nm peak was higher than the control one. Under RF, the 490 nm peak decreased compared to the 460 nm one. The decreasing was stronger for the sample in the higher field. The ratio of the emission area of the 490 nm to 460 nm was 5 for the control sample. It decreased up to 1.6 for the samples under RF. The bioluminescence improves the DNA repair by photoreactivation, and there is evidence that photolyase is preferentially activated by blue/violet light. Our finding suggests that RF exposure may stimulate DNA repair by shifting the emission spectra from blue/green (490 nm) to blue/violet (460 nm).

  9. Real-time synthetic aperture ultrasonic scroll-imaging system and imaging experiment for nuclear power plant NDT

    The authors discuss their development of a real-time synthetic aperture imaging system which provides a cross sectional image of an object in real-time. They have already confirmed the performance of the system by imaging experiments using the normal-beam method. To confirm the wide applicability of the system, they have carried out imaging experiments with the angle-beam method. They considered four different sound paths for angle-beam SAFT imaging. After calculating sound path lengths, computer simulation and experiments were carried out. It is shown that there were two dominant paths for image reconstruction caused by the directivity of the transducer

  10. Image Corruption Detection in Diffusion Tensor Imaging for Post-Processing and Real-Time Monitoring

    Li, Yue; Shea, Steven M.; Lorenz, Christine H.; Jiang, Hangyi; Chou, Ming-Chung; Mori, Susumu

    2013-01-01

    Due to the high sensitivity of diffusion tensor imaging (DTI) to physiological motion, clinical DTI scans often suffer a significant amount of artifacts. Tensor-fitting-based, post-processing outlier rejection is often used to reduce the influence of motion artifacts. Although it is an effective approach, when there are multiple corrupted data, this method may no longer correctly identify and reject the corrupted data. In this paper, we introduce a new criterion called “corrected Inter-Slice Intensity Discontinuity” (cISID) to detect motion-induced artifacts. We compared the performance of algorithms using cISID and other existing methods with regard to artifact detection. The experimental results show that the integration of cISID into fitting-based methods significantly improves the retrospective detection performance at post-processing analysis. The performance of the cISID criterion, if used alone, was inferior to the fitting-based methods, but cISID could effectively identify severely corrupted images with a rapid calculation time. In the second part of this paper, an outlier rejection scheme was implemented on a scanner for real-time monitoring of image quality and reacquisition of the corrupted data. The real-time monitoring, based on cISID and followed by post-processing, fitting-based outlier rejection, could provide a robust environment for routine DTI studies. PMID:24204551

  11. Results from laboratory tests of the two-dimensional Time-Encoded Imaging System.

    Marleau, Peter; Brennan, James S.; Brubaker, Erik; Gerling, Mark D; Le Galloudec, Nathalie Joelle

    2014-09-01

    A series of laboratory experiments were undertaken to demonstrate the feasibility of two dimensional time-encoded imaging. A prototype two-dimensional time encoded imaging system was designed and constructed. Results from imaging measurements of single and multiple point sources as well as extended source distributions are presented. Time encoded imaging has proven to be a simple method for achieving high resolution two-dimensional imaging with potential to be used in future arms control and treaty verification applications.

  12. Monitoring of historical frescoes by timed infrared imaging analysis

    Cadelano, G.; Bison, P.; Bortolin, A.; Ferrarini, G.; Peron, F.; Girotto, M.; Volinia, M.

    2015-03-01

    The subflorescence and efflorescence phenomena are widely acknowledged as the major causes of permanent damage to fresco wall paintings. They are related to the occurrence of cycles of dry/wet conditions inside the walls. Therefore, it is essential to identify the presence of water on the decorated surfaces and inside the walls. Nondestructive testing in industrial applications have confirmed that active infrared thermography with continuous timed images acquisition can improve the outcomes of thermal analysis aimed to moisture identification. In spite of that, in cultural heritage investigations these techniques have not been yet used extensively on a regular basis. This paper illustrates an application of these principles in order to evaluate the decay of fresco mural paintings in a medieval chapel located in North-West of Italy. One important feature of this study is the use of a robotic system called aIRview that can be utilized to automatically acquire and process thermal images. Multiple accurate thermal views of the inside walls of the building have been produced in a survey that lasted several days. Signal processing algorithms based on Fast Fourier Transform analysis have been applied to the acquired data in order to formulate trustworthy hypotheses about the deterioration mechanisms.

  13. Implementation of real-time digital endoscopic image processing system

    Song, Chul Gyu; Lee, Young Mook; Lee, Sang Min; Kim, Won Ky; Lee, Jae Ho; Lee, Myoung Ho

    1997-10-01

    Endoscopy has become a crucial diagnostic and therapeutic procedure in clinical areas. Over the past four years, we have developed a computerized system to record and store clinical data pertaining to endoscopic surgery of laparascopic cholecystectomy, pelviscopic endometriosis, and surgical arthroscopy. In this study, we developed a computer system, which is composed of a frame grabber, a sound board, a VCR control board, a LAN card and EDMS. Also, computer system controls peripheral instruments such as a color video printer, a video cassette recorder, and endoscopic input/output signals. Digital endoscopic data management system is based on open architecture and a set of widely available industry standards; namely Microsoft Windows as an operating system, TCP/IP as a network protocol and a time sequential database that handles both images and speech. For the purpose of data storage, we used MOD and CD- R. Digital endoscopic system was designed to be able to store, recreate, change, and compress signals and medical images. Computerized endoscopy enables us to generate and manipulate the original visual document, making it accessible to a virtually unlimited number of physicians.

  14. Real-time imaging for neutron radiography at KURRI

    For neutron radiography (NR), photographic techniques have been mainly used for many years. To observe a dynamic event and to test many samples, the real-time neutron radiography (i.e. neutron television - NTV) system has been introduced at the E-2 experimental tube of the Kyoto University Research Reactor (KUR). The NTV system has been practically applied to penetrating the side plates containing boron burnable poison to test MTR type reactor fuel, to investigation of moving objects and to neutron computed tomography (NCT). New approaches using some advanced neutron converters, a high sensitive and resolution TV camera and a high performance image processing system are being undertaken for standard indicators, visualization on air-water two-phase flow, NCT and so on. (author)

  15. Real Time Deconvolution of In-Vivo Ultrasound Images

    Jensen, Jørgen Arendt

    algorithm using averaging over several RF lines. In vivo data from a 3 MHz mechanically rotating probe is used and the received signal is sampled at 20 MHz and 12 bits. In-vivo data acquired from a 16th week old fetus is used along with a scan from the liver and right kidney of a 27 years old male. The...... corresponding to a factor of 5.1. The basic pulse can be estimated in roughly 0.176 seconds on a single CPU core on an Intel i5 CPU running at 1.8 GHz. An in-vivo image consisting of 100 lines of 1600 samples can be processed in roughly 0.1 seconds making it possible to perform real-time deconvolution on...

  16. Chern numbers hiding in time-of-flight images

    We present a technique for detecting topological invariants--Chern numbers--from time-of-flight images of ultracold atoms. We show that the Chern numbers of integer quantum Hall states of lattice fermions leave their fingerprints in the atoms' momentum distribution. We analytically demonstrate that the number of local maxima in the momentum distribution is equal to the Chern number in two limiting cases, for large hopping anisotropy and in the continuum limit. In addition, our numerical simulations beyond these two limits show that these local maxima persist for a range of parameters. Thus, an everyday observable in cold atom experiments can serve as a useful tool to characterize and visualize quantum states with nontrivial topology.

  17. Fluorophore-NanoLuc BRET Reporters Enable Sensitive In Vivo Optical Imaging and Flow Cytometry for Monitoring Tumorigenesis.

    Schaub, Franz X; Reza, Md Shamim; Flaveny, Colin A; Li, Weimin; Musicant, Adele M; Hoxha, Sany; Guo, Min; Cleveland, John L; Amelio, Antonio L

    2015-12-01

    Fluorescent proteins are widely used to study molecular and cellular events, yet this traditionally relies on delivery of excitation light, which can trigger autofluorescence, photoxicity, and photobleaching, impairing their use in vivo. Accordingly, chemiluminescent light sources such as those generated by luciferases have emerged, as they do not require excitation light. However, current luciferase reporters lack the brightness needed to visualize events in deep tissues. We report the creation of chimeric eGFP-NanoLuc (GpNLuc) and LSSmOrange-NanoLuc (OgNLuc) fusion reporter proteins coined LumiFluors, which combine the benefits of eGFP or LSSmOrange fluorescent proteins with the bright, glow-type bioluminescent light generated by an enhanced small luciferase subunit (NanoLuc) of the deep-sea shrimp Oplophorus gracilirostris. The intramolecular bioluminescence resonance energy transfer that occurs between NanoLuc and the fused fluorophore generates the brightest bioluminescent signal known to date, including improved intensity, sensitivity, and durable spectral properties, thereby dramatically reducing image acquisition times and permitting highly sensitive in vivo imaging. Notably, the self-illuminating and bifunctional nature of these LumiFluor reporters enables greatly improved spatiotemporal monitoring of very small numbers of tumor cells via in vivo optical imaging and also allows the isolation and analyses of single cells by flow cytometry. Thus, LumiFluor reporters are inexpensive, robust, noninvasive tools that allow for markedly improved in vivo optical imaging of tumorigenic processes. PMID:26424696

  18. Imaging system for obtaining space- and time-resolved plasma images on TMX

    A Reticon 50 x 50 photodiode array camera has been placed on Livermore's Tandem Mirror Experiment to view a 56-cm diameter plasma source of visible, vacuum-ultraviolet, and x-ray photons. The compact camera views the source through a pinhole, filters, a fiber optic coupler, a microchannel plate intensifier (MCPI), and a reducer. The images are digitized (at 3.3 MHz) and stored in a large, high-speed memory that has a capacity of 45 images. A local LSI-11 microprocessor provides immediate processing and display of the data. The data are also stored on floppy disks that can be further processed on the large Livermore Computer System. The temporal resolution is limited by the fastest MCPI gate. The number of images recorded is determined by the read-out time of the Reticon camera (minimum 0.9 msec). The spatial resolution of approximately 1.4 cm is fixed by the geometry and the pinhole of 0.025 cm. Typical high-quality color representation of some plasma images are included

  19. Real-time deblurring of handshake blurred images on smartphones

    Pourreza-Shahri, Reza; Chang, Chih-Hsiang; Kehtarnavaz, Nasser

    2015-02-01

    This paper discusses an Android app for the purpose of removing blur that is introduced as a result of handshakes when taking images via a smartphone. This algorithm utilizes two images to achieve deblurring in a computationally efficient manner without suffering from artifacts associated with deconvolution deblurring algorithms. The first image is the normal or auto-exposure image and the second image is a short-exposure image that is automatically captured immediately before or after the auto-exposure image is taken. A low rank approximation image is obtained by applying singular value decomposition to the auto-exposure image which may appear blurred due to handshakes. This approximation image does not suffer from blurring while incorporating the image brightness and contrast information. The eigenvalues extracted from the low rank approximation image are then combined with those from the shortexposure image. It is shown that this deblurring app is computationally more efficient than the adaptive tonal correction algorithm which was previously developed for the same purpose.

  20. Digital image processing for real-time neutron radiography and its applications

    The present paper describes several digital image processing approaches for the real-time neutron radiography (neutron television-NTV), such as image integration, adaptive smoothing and image enhancement, which have beneficial effects on image improvements, and also describes how to use these techniques for applications. Details invisible in direct images of NTV are able to be revealed by digital image processing, such as reversed image, gray level correction, gray scale transformation, contoured image, subtraction technique, pseudo color display and so on. For real-time application a contouring operation and an averaging approach can also be utilized effectively. (author)

  1. Forming rotated SAR images by real-time motion compensation.

    Doerry, Armin Walter

    2012-12-01

    Proper waveform parameter selection allows collecting Synthetic Aperture Radar (SAR) phase history data on a rotated grid in the Fourier Space of the scene being imaged. Subsequent image formation preserves the rotated geometry to allow SAR images to be formed at arbitrary rotation angles without the use of computationally expensive interpolation or resampling operations. This should be useful where control of image orientation is desired such as generating squinted stripmaps and VideoSAR applications, among others.

  2. Using bioluminescent biosensors for hazard analysis and critical control point (HACCP) in wastewater control.

    Valat, C; Champiat, D; Degorce-Dumas, J R; Thomas, O

    2004-01-01

    Starting from a new approach for water pollution control and wastewater treatment plant management, the hazard analysis and critical control point (HACCP) quality concept, the interest for the development of new rapid and sensitive methods such as bioluminescence-based methods is evident. After an introduction of the HACCP procedure, a bibliographic study of the bioluminescence potentiality is presented and discussed. PMID:14979548

  3. Real-time sono-photoacoustic imaging of gold nanoemulsions

    Arnal, Bastien; Wei, Chen-Wei; Perez, Camilo; Lombardo, Michael; Pelivanov, Ivan M.; Pozzo, Danilo; O'Donnell, Matthew

    2015-03-01

    Phase transition contrast agents were first introduced in ultrasound (US) in the form of perfluorocarbon droplets. When their size is reduced to the nanoscale, surface tension dominates their stability and high pressure is required to vaporize them using long US emissions at high frequencies. Our group recently showed that nanoemulsion beads (100-300 nm) coated with gold nanopsheres could be used as non-linear contrast agents. Beads can be vaporized with light only, inducing stronger photoacoustic signals by increasing thermal expansion. A photoacoustic cavitation threshold study (US: 1.2 MHz, Laser 750 nm and 10-ns pulse) shows that the vaporization thresholds of NEB-GNS can be greatly reduced using simultaneous light and US excitations. The resulting signal is driven only by the pressure amplitude for a fluence higher than 2.4 mJ/cm2. At diagnostic exposures, it is possible to capture very high signals from the vaporized beads at concentrations reduced to 10 pM with optical absorption smaller than 0.01 cm-1. A real-time imaging mode selectively isolating vaporization signals was implemented on a Verasonics system. A linear US probe (L74, 3 MHz) launched short US bursts before light was emitted from the laser. Vaporization of NEB-GNS resulted in a persistent 30-dB signal enhancement compared to a dye with the same absorption. Specific vaporization signals were retrieved in phantom experiments with US scatterers. This technique, called sonophotoacoustics, has great potential for targeted molecular imaging and therapy using compact nanoprobes with potentially high-penetrability into tissue.

  4. Real-time image processing of TOF range images using a reconfigurable processor system

    Hussmann, S.; Knoll, F.; Edeler, T.

    2011-07-01

    During the last years, Time-of-Flight sensors achieved a significant impact onto research fields in machine vision. In comparison to stereo vision system and laser range scanners they combine the advantages of active sensors providing accurate distance measurements and camera-based systems recording a 2D matrix at a high frame rate. Moreover low cost 3D imaging has the potential to open a wide field of additional applications and solutions in markets like consumer electronics, multimedia, digital photography, robotics and medical technologies. This paper focuses on the currently implemented 4-phase-shift algorithm in this type of sensors. The most time critical operation of the phase-shift algorithm is the arctangent function. In this paper a novel hardware implementation of the arctangent function using a reconfigurable processor system is presented and benchmarked against the state-of-the-art CORDIC arctangent algorithm. Experimental results show that the proposed algorithm is well suited for real-time processing of the range images of TOF cameras.

  5. A Novel Algorithm to Perform Precalculated Tables for the Real-Time Image Processing: Illustration with Image Rotation

    Devy, M.; IRKI, Z.

    2011-01-01

    In this paper, we present an approach which makes uses of precalculated tables in order to carry out a real time image processing task. This approach is very useful when the relation between the input image and the output image (after treatment) is given in the backward direction (the input image is expressed using the output image). We illustrate this approach in the case of the rotation of an image around its center. We illustrate how theses precalculated tables should be built and the ...

  6. Imaging tooth enamel using zero echo time (ZTE) magnetic resonance imaging

    Rychert, Kevin M.; Zhu, Gang; Kmiec, Maciej M.; Nemani, Venkata K.; Williams, Benjamin B.; Flood, Ann B.; Swartz, Harold M.; Gimi, Barjor

    2015-03-01

    In an event where many thousands of people may have been exposed to levels of radiation that are sufficient to cause the acute radiation syndrome, we need technology that can estimate the absorbed dose on an individual basis for triage and meaningful medical decision making. Such dose estimates may be achieved using in vivo electron paramagnetic resonance (EPR) tooth biodosimetry, which measures the number of persistent free radicals that are generated in tooth enamel following irradiation. However, the accuracy of dose estimates may be impacted by individual variations in teeth, especially the amount and distribution of enamel in the inhomogeneous sensitive volume of the resonator used to detect the radicals. In order to study the relationship between interpersonal variations in enamel and EPR-based dose estimates, it is desirable to estimate these parameters nondestructively and without adding radiation to the teeth. Magnetic Resonance Imaging (MRI) is capable of acquiring structural and biochemical information without imparting additional radiation, which may be beneficial for many EPR dosimetry studies. However, the extremely short T2 relaxation time in tooth structures precludes tooth imaging using conventional MRI methods. Therefore, we used zero echo time (ZTE) MRI to image teeth ex vivo to assess enamel volumes and spatial distributions. Using these data in combination with the data on the distribution of the transverse radio frequency magnetic field from electromagnetic simulations, we then can identify possible sources of variations in radiation-induced signals detectable by EPR. Unlike conventional MRI, ZTE applies spatial encoding gradients during the RF excitation pulse, thereby facilitating signal acquisition almost immediately after excitation, minimizing signal loss from short T2 relaxation times. ZTE successfully provided volumetric measures of tooth enamel that may be related to variations that impact EPR dosimetry and facilitate the development of analytical procedures for individual dose estimates.

  7. Time-resolved Optical Tomography instrumentation for fast 3D functional imaging.

    Jennions, D. K.

    2008-01-01

    Optical Tomography is a medical imaging method for creating three-dimensional images using near infrared light. An instrument, named MONSTIR (Multi-channel Opto-electronic Near-infrared System for Time-resolved Image Reconstruction), has been designed and built to measure the flight times of photons between two positions on the surface of the tissue being imaged. The measurements are used to generate functional images of the newborn infant brain, and to detect and classify breast disease. The...

  8. A Remote Laboratory for Real-Time Digital Image Processing on Embedded Systems

    Evangelos Zigouris; Dimitrios Markonis; Athanasios Kalantzopoulos

    2009-01-01

    The purpose of this paper is to present a Remote Laboratory on embedded systems focused in real-time digital image processing. This laboratory consists of a Main Web Server and several Workstations which are designed for digital image retrieval from a CMOS Image Sensor and real-time image processing on a Digital Signal Processor development platform. The Main Web Server redirects the authorised remote users to available Workstations in order to execute and verify their image processing algori...

  9. Improving the Image Quality of Synthetic Transmit Aperture Ultrasound Images - Achieving Real-Time In-Vivo Imaging

    Gammelmark, Kim

    2004-01-01

    Synthetic transmit aperture (STA) imaging has the potential to increase the image quality of medical ultrasound images beyond the levels obtained by conventional imaging techniques (linear, phased, and convex array imaging). Currently, however, in-vivo applications of STA imaging is limited by a ...... convex array TMS imaging compared to conventional convex array imaging. Only minor motion artifacts causing subtle image brightness fluctuations were reported in TMS imaging, which did not depreciate the diagnostic value of the images. The influence of tissue motion and a method for two...

  10. Real-time image-processing algorithm for markerless tumour tracking using X-ray fluoroscopic imaging

    2014-01-01

    Objective: To ensure accuracy in respiratory-gating treatment, X-ray fluoroscopic imaging is used to detect tumour position in real time. Detection accuracy is strongly dependent on image quality, particularly positional differences between the patient and treatment couch. We developed a new algorithm to improve the quality of images obtained in X-ray fluoroscopic imaging and report the preliminary results. Methods: Two oblique X-ray fluoroscopic images were acquired using a dynamic flat panel detector (DFPD) for two patients with lung cancer. The weighting factor was applied to the DFPD image in respective columns, because most anatomical structures, as well as the treatment couch and port cover edge, were aligned in the superior–inferior direction when the patient lay on the treatment couch. The weighting factors for the respective columns were varied until the standard deviation of the pixel values within the image region was minimized. Once the weighting factors were calculated, the quality of the DFPD image was improved by applying the factors to multiframe images. Results: Applying the image-processing algorithm produced substantial improvement in the quality of images, and the image contrast was increased. The treatment couch and irradiation port edge, which were not related to a patient's position, were removed. The average image-processing time was 1.1 ms, showing that this fast image processing can be applied to real-time tumour-tracking systems. Conclusion: These findings indicate that this image-processing algorithm improves the image quality in patients with lung cancer and successfully removes objects not related to the patient. Advances in knowledge: Our image-processing algorithm might be useful in improving gated-treatment accuracy. PMID:24661056

  11. High resolution, near real-time x-ray video imaging without image intensification

    This paper discusses a type of x-ray camera designed to generate standard RS-170 video output that does not use x-ray or optical image intensifiers. Instead, it employs a very sensitive, very high resolution, CCD sensor which views an x-ray-to-light conversion screen directly through a high speed imaging lens. This new solid state TV camera, which will be described later, has very low readout noise plus unusually high gain which enables it to generate real-time video with incident flux levels typical of many inspection applications. Perhaps more important is an ability to integrate for multiple frame intervals on the chip followed by the output of a standard, RS-170 format video frame containing two balanced interlaced fields. In this integrating mode excellent quality images of low contrast objects can be obtained with only a few tenths of a second integrating intervals. The basic elements of this type of camera will be described and applications discussed where this approach appears to have important advantages over other methods in common use. Also included is an analytical/numerical discussion which supports some of the important points

  12. TimeLapseAnalyzer: Multi-target analysis for live-cell imaging and time-lapse microscopy

    Huth, Johannes; Buchholz, Malte; Kraus, Johann M.; Mølhave, Kristian; Gradinaru, Cristian; v. Wichert, Götz; Gress, Thomas M.; Neumann, Heiko; Kestler, Hans A.

    2011-01-01

    biomarker discovery and diagnostic decisions. Given the vast amount of image- and time-series data produced by modern microscopes, automated analysis is a key feature to capitalize the potential of time-lapse imaging devices. To provide fast and reproducible analyses of multiple aspects of cell behaviour...

  13. Real-time image acquisition and deblurring for underwater gravel extraction by smartphone

    Ming-Fu Chen

    2014-02-01

    Full Text Available Gravel size distribution is an important aspect of stream investigation. Using water photography to determine such distribution is a simple and cost-effective approach for gathering instream gravel information. However, good-quality images of underwater gravels in shallow areas are difficult to acquire because of the flow- and wind-induced perturbation at water surface. Thus, two LucyRichardson iterations are applied on an averaged image to obtain a deblurred image for gravel extraction. A Matlab code for multi-frame image averaging and image deblurring is implemented on a laptop computer. Underwater gravel images are acquired using a video camera and processed offline. Thus, the usability of the images acquired during field investigation cannot be determined immediately. However, returning to the investigated streams for additional data gathering would be costly, and the cameras may accidentally be dropped into the water. This paper presents multi-frame image averaging and image deblurring smartphone-based approaches for underwater gravel extraction. A waterproof smartphone is used to acquire the images, on which image deblurring is immediately conducted to test whether the images can be used for gravel extraction. The averaged image of using mean-based filter is derived during real-time image acquisition. The deblurred image is derived block-by-block because of limited memory capacity of smartphones. The time consumed for acquiring 1500 frame images with size of 1280 720 pixels is approximately 6 min by Sony Xperia smartphones. Image averaging can be performed in real time during image acquisition. Image deblurring is accomplished accurately and is consistent with results of the Matlab code. The processing time for image deblurring is approximately 12 min. A compact system for underwater gravel investigation using smartphones is successfully developed in this study. Image acquisition and deblurring are completed in real time at the investigated fields. Thus, we can immediately test whether the acquired images are usable for gravel extraction, thereby improving investigation efficiency significantly.

  14. Inhibitory effect of lipoic acid on firefly luciferase bioluminescence

    Lipoic acid was found to inhibit the firefly luciferin-luciferase reaction. The inhibition is competitive and is the strongest known (Ki 0.026 ± 0.013 μM) compared with other reported inhibitors. Considering the structure-activity correlations, the mechanism of inhibition may originate from the sulfur atom and carboxyl moiety of lipoic acid giving it structural specificity. Subsequent addition of lipoic acid and nitric oxide accelerated the inhibition in vitro, suggesting that lipoic acid may have a functional role in regulating firefly bioluminescence

  15. Bioluminescence Probe for Detecting Hydrogen Sulfide in Vivo.

    Ke, Bowen; Wu, Wenxiao; Liu, Wei; Liang, Hong; Gong, Deying; Hu, Xiaotong; Li, Minyong

    2016-01-01

    Considering that hydrogen sulfide (H2S) is an endogenous signaling molecule involved in numerous biological processes, a method for monitoring H2S as a powerful tool for investigating its complicated functions and mechanisms is urgently demanded. Herein, a bioluminescent turn-on probe was reported based on caged strategy for the detection of H2S in vitro and in vivo. This probe will help us understand the intricate contribution of H2S to a variety of physiological and pathological processes. PMID:26634959

  16. Toxicity assessment of Hanford Site wastes by bacterial bioluminescence

    This paper examines the toxicity of the nonradioactive component of low-level wastes stored in tanks on the Hanford reservation. The use of a faster, cheaper bioassay to replace the 96 hour fish acute toxicity test is examined. The new bioassay is based on loss of bioluminescence of Photobacter phosphoreum (commonly called Microtox) following exposure to toxic materials. This bioassay is calibrated and compares well to the standard fish acute toxicity test for characterization of Hanford Wastes. 4 refs., 11 figs., 11 tabs

  17. Prey attraction as a possible function of bioluminescence in the larvae of Pyrearinus termitilluminans (Coleoptera: Elateridae

    Kent H. Redford

    1982-01-01

    Full Text Available Elaterid beetle larvae. Pyrearinus termitilluminans (sp.n., Costa, 1982. live in termite mounds in central Brazil. Each larva produces light in the segment immediately behind its head. Larvae were observed to luminesce only during the first weeks of the rainy season, the same times as the ant and termite alate flights. Alates, apparently attracted to P. termitilluminans larval lights, serve as an important food source for the larvae. The prey-catching and food-storing behavior and the phenomenon of bioluminescence are apparently an evolutionary response by P. termitilluminans larvae to a short, rich pulse of food. Prey attraction as a probable cause for luminescence has been suggested only twice before.

  18. The nucleotide sequence of Beneckea harveyi 5S rRNA. [bioluminescent marine bacterium

    Luehrsen, K. R.; Fox, G. E.

    1981-01-01

    The primary sequence of the 5S ribosomal RNA isolated from the free-living bioluminescent marine bacterium Beneckea harveyi is reported and discussed in regard to indications of phylogenetic relationships with the bacteria Escherichia coli and Photobacterium phosphoreum. Sequences were determined for oligonucleotide products generated by digestion with ribonuclease T1, pancreatic ribonuclease and ribonuclease T2. The presence of heterogeneity is indicated for two sites. The B. harveyi sequence can be arranged into the same four helix secondary structures as E. coli and other prokaryotic 5S rRNAs. Examination of the 5S-RNS sequences of the three bacteria indicates that B. harveyi and P. phosphoreum are specifically related and share a common ancestor which diverged from an ancestor of E. coli at a somewhat earlier time, consistent with previous studies.

  19. Prey attraction as a possible function of bioluminescence in the larvae of Pyrearinus termitilluminans (Coleoptera: Elateridae)

    Kent H., Redford.

    Full Text Available Elaterid beetle larvae. Pyrearinus termitilluminans (sp.n., Costa, 1982.) live in termite mounds in central Brazil. Each larva produces light in the segment immediately behind its head. Larvae were observed to luminesce only during the first weeks of the rainy season, the same times as the ant and t [...] ermite alate flights. Alates, apparently attracted to P. termitilluminans larval lights, serve as an important food source for the larvae. The prey-catching and food-storing behavior and the phenomenon of bioluminescence are apparently an evolutionary response by P. termitilluminans larvae to a short, rich pulse of food. Prey attraction as a probable cause for luminescence has been suggested only twice before.

  20. Density resolutionary optimization of real time radiotherapy portal imagings

    Objective: Electronic portal imaging devices (EPIDs) are widely used as a replacement of portal films for patient position verification, but the image quality is not always optimal. Because of very low density resolution, the portal imaging is difficult to be used clinically. In this study, several transforming models and the optimization exposure or acquisition conditions were studied for optimization portal imaging, which based on DicomRT platform built by ourselves. Methods: 6 MV X-ray from Varian 21EX linac was used to generate portal images by Portal Vision aSi500 amorphous silicon detector image acquisition system. The density resolution study was based on the number of the lines which could be seen in the image of a special Las Vegas image quality test board. The optimization calculating models were focused on equalization after stretch transforming discrete wavelet transform (DWT) and Butter worth high pass filters. The calculation was performed in Matlab language. Results: The optimal numbers of MU, average frames and reset number were 4 - 5, 3 - 4 and 2 - 3, respectively. The density resolution of optimized imaging via equalization after stretch transforming, DWT and Butter worth high pass filter transforming was markedly improved. The bone structure could be definitely distinguished. The number of lines distinguished in Las Vegas image via equalization after stretch transforming, DWT and Better worth high pass filter transforming was 3, 4 and 5, respectively. Conclusions: The proposed transforming systems, including DWT edge detection and Butter worth high pass filter transform, are suitable for improving density resolving power of MV X-ray portal image. (authors)

  1. Bioluminescncia de fungos: distribuio, funo e mecanismo de emisso de luz / Fungi bioluminescence: distribution, function and mechanism of light emission

    Anderson Garbuglio, Oliveira; Rodrigo Pimenta, Carvalho; Hans Eugene, Waldenmaier; Cassius Vinicius, Stevani.

    Full Text Available [...] Abstract in english The emission of light by living organisms, bioluminescence, has been studied since the nineteenth century. However, some bioluminescent systems, such as fungi, remain poorly understood. The emitter, the two enzymes involved, and the reaction mechanism have not yet been unraveled. Moreover, the ecolo [...] gical role and evolutionary significance for fungal luminescence is also unknown. It is hoped that comprehensive research on fungal bioluminescent systems will generate knowledge and tools for academic and applied sciences. This review discusses the distribution of bioluminescent fungi on Earth, attempts to elucidate the mechanism involved in light emission, and presents preliminary results on the evolution and ecological role of fungal bioluminescence.

  2. When should we recommend use of dual time-point and delayed time-point imaging techniques in FDG PET?

    Cheng, Gang [Philadelphia VA Medical Center, Department of Radiology, Philadelphia, PA (United States); Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Torigian, Drew A.; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Zhuang, Hongming [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2013-05-15

    FDG PET and PET/CT are now widely used in oncological imaging for tumor characterization, staging, restaging, and response evaluation. However, numerous benign etiologies may cause increased FDG uptake indistinguishable from that of malignancy. Multiple studies have shown that dual time-point imaging (DTPI) of FDG PET may be helpful in differentiating malignancy from benign processes. However, exceptions exist, and some studies have demonstrated significant overlap of FDG uptake patterns between benign and malignant lesions on delayed time-point images. In this review, we summarize our experience and opinions on the value of DTPI and delayed time-point imaging in oncology, with a review of the relevant literature. We believe that the major value of DTPI and delayed time-point imaging is the increased sensitivity due to continued clearance of background activity and continued FDG accumulation in malignant lesions, if the same diagnostic criteria (as in the initial standard single time-point imaging) are used. The specificity of DTPI and delayed time-point imaging depends on multiple factors, including the prevalence of malignancies, the patient population, and the cut-off values (either SUV or retention index) used to define a malignancy. Thus, DTPI and delayed time-point imaging would be more useful if performed for evaluation of lesions in regions with significant background activity clearance over time (such as the liver, the spleen, the mediastinum), and if used in the evaluation of the extent of tumor involvement rather than in the characterization of the nature of any specific lesion. Acute infectious and non-infectious inflammatory lesions remain as the major culprit for diminished diagnostic performance of these approaches (especially in tuberculosis-endemic regions). Tumor heterogeneity may also contribute to inconsistent performance of DTPI. The authors believe that selective use of DTPI and delayed time-point imaging will improve diagnostic accuracy and interpretation confidence in FDG PET imaging. (orig.)

  3. Monitoring Therapeutic Treatments against Burkholderia Infections Using Imaging Techniques

    Tiffany M. Mott

    2013-05-01

    Full Text Available Burkholderia mallei, the etiologic agent of glanders, are Category B select agents with biothreat potential, and yet effective therapeutic treatments are lacking. In this study, we showed that CpG administration increased survival, demonstrating protection in the murine glanders model. Bacterial recovery from infected lungs, liver and spleen was significantly reduced in CpG-treated animals as compared with non-treated mice. Reciprocally, lungs of CpG-treated infected animals were infiltrated with higher levels of neutrophils and inflammatory monocytes, as compared to control animals. Employing the B. mallei bioluminescent strain CSM001 and the Neutrophil-Specific Fluorescent Imaging Agent, bacterial dissemination and neutrophil trafficking were monitored in real-time using multimodal in vivo whole body imaging techniques. CpG-treatment increased recruitment of neutrophils to the lungs and reduced bioluminescent bacteria, correlating with decreased bacterial burden and increased protection against acute murine glanders. Our results indicate that protection of CpG-treated animals was associated with recruitment of neutrophils prior to infection and demonstrated, for the first time, simultaneous real time in vivo imaging of neutrophils and bacteria. This study provides experimental evidence supporting the importance of incorporating optimized in vivo imaging methods to monitor disease progression and to evaluate the efficacy of therapeutic treatment during bacterial infections.

  4. Space-time encoding for high frame rate ultrasound imaging

    Misaridis, Thanssis; Jensen, Jørgen Arendt

    Frame rate in ultrasound imaging can be dramatically increased by using sparse synthetic transmit aperture (STA) beamforming techniques. The two main drawbacks of the method are the low signal-to-noise ratio (SNR) and the motion artifacts, that degrade the image quality. In this paper we propose ...

  5. Towards microwave system for real-time medical imaging

    Guardiola Garcia, Marta; Buitrago Ventura, Santiago; Romeu Robert, Jordi; Jofre Roca, Lluís

    2014-01-01

    Microwave tomography is proposed for medical diagnosis using Magnitude Combined tomographic algorithm. A proof-of-concept experimental system was build and an in-homogeneous breast phantom with a tumor embedded was successfully reconstructed in less than 30 seconds per frequency. The motivation for this study is the future development of an imaging prototype for head imaging.

  6. Real-time progressive hyperspectral image processing endmember finding and anomaly detection

    Chang, Chein-I

    2016-01-01

    The book covers the most crucial parts of real-time hyperspectral image processing: causality and real-time capability. Recently, two new concepts of real time hyperspectral image processing, Progressive Hyperspectral Imaging (PHSI) and Recursive Hyperspectral Imaging (RHSI). Both of these can be used to design algorithms and also form an integral part of real time hyperpsectral image processing. This book focuses on progressive nature in algorithms on their real-time and causal processing implementation in two major applications, endmember finding and anomaly detection, both of which are fundamental tasks in hyperspectral imaging but generally not encountered in multispectral imaging. This book is written to particularly address PHSI in real time processing, while a book, Recursive Hyperspectral Sample and Band Processing: Algorithm Architecture and Implementation (Springer 2016) can be considered as its companion book. Includes preliminary background which is essential to those who work in hyperspectral ima...

  7. Collinear, two-color optical Kerr effect shutter for ultrafast time-resolved imaging

    Purwar, Harsh; Rozé, Claude; Sedarsky, David; Blaisot, Jean-Bernard

    2015-01-01

    Imaging with ultrashort exposure times is generally achieved with a crossed-beam geometry. In the usual arrangement, an off-axis gating pulse induces birefringence in a medium exhibiting a strong Kerr response (commonly carbon disulfide) which is followed by a polarizer aligned to fully attenuate the on-axis imaging beam. By properly timing the gate pulse, imaging light experiences a polarization change allowing time-dependent transmission through the polarizer to form an ultrashort image. The crossed-beam system is effective in generating short gate times, however, signal transmission through the system is complicated by the crossing angle of the gate and imaging beams. This work presents a robust ultrafast time-gated imaging scheme based on a combination of type-I frequency doubling and a collinear optical arrangement in carbon disulfide. We discuss spatial effects arising from crossed-beam Kerr gating, and examine the imaging spatial resolution and transmission timing affected by collinear activation of th...

  8. Real-time computer-generated integral imaging and 3D image calibration for augmented reality surgical navigation.

    Wang, Junchen; Suenaga, Hideyuki; Liao, Hongen; Hoshi, Kazuto; Yang, Liangjing; Kobayashi, Etsuko; Sakuma, Ichiro

    2015-03-01

    Autostereoscopic 3D image overlay for augmented reality (AR) based surgical navigation has been studied and reported many times. For the purpose of surgical overlay, the 3D image is expected to have the same geometric shape as the original organ, and can be transformed to a specified location for image overlay. However, how to generate a 3D image with high geometric fidelity and quantitative evaluation of 3D image's geometric accuracy have not been addressed. This paper proposes a graphics processing unit (GPU) based computer-generated integral imaging pipeline for real-time autostereoscopic 3D display, and an automatic closed-loop 3D image calibration paradigm for displaying undistorted 3D images. Based on the proposed methods, a novel AR device for 3D image surgical overlay is presented, which mainly consists of a 3D display, an AR window, a stereo camera for 3D measurement, and a workstation for information processing. The evaluation on the 3D image rendering performance with 25601600 elemental image resolution shows the rendering speeds of 50-60 frames per second (fps) for surface models, and 5-8 fps for large medical volumes. The evaluation of the undistorted 3D image after the calibration yields sub-millimeter geometric accuracy. A phantom experiment simulating oral and maxillofacial surgery was also performed to evaluate the proposed AR overlay device in terms of the image registration accuracy, 3D image overlay accuracy, and the visual effects of the overlay. The experimental results show satisfactory image registration and image overlay accuracy, and confirm the system usability. PMID:25465067

  9. Bioluminescent detection probe for tick-borne encephalitis virus immunoassay.

    Burakova, Ludmila P; Kudryavtsev, Alexander N; Stepanyuk, Galina A; Baykov, Ivan K; Morozova, Vera V; Tikunova, Nina V; Dubova, Maria A; Lyapustin, Victor N; Yakimenko, Valeri V; Frank, Ludmila A

    2015-07-01

    To facilitate the detection of the tick-borne encephalitis virus (TBEV), the causative agent of one of the most severe human neuroinfections, we have developed an immunoassay based on bioluminescent hybrid protein 14D5a-Rm7 as a detection probe. The protein containing Renilla luciferase as a reporter and a single-chain variable fragment (scFv) of murine immunoglobulin to TBEV as a recognition element was constructed, produced by bacterial expression, purified, and tested. Both domains were shown to reveal their specific biological properties-affinity to the target antigen and bioluminescent activity. Hybrid protein was applied as a label for solid-phase immunoassay of the antigens, associated with the tick-borne encephalitis virus (native glycoprotein E or extracts of the infected strain of lab ticks). The assay demonstrates high sensitivity (0.056 ng of glycoprotein E; 10(4)-10(5) virus particles or 0.1 pg virions) and simplicity and is competitive with conventional methods for detection of TBEV. PMID:25925861

  10. Bioluminescence regenerative cycle (BRC) system for nucleic acid quantification assays

    Hassibi, Arjang; Lee, Thomas H.; Davis, Ronald W.; Pourmand, Nader

    2003-07-01

    A new label-free methodology for nucleic acid quantification has been developed where the number of pyrophosphate molecules (PPi) released during polymerization of the target nucleic acid is counted and correlated to DNA copy number. The technique uses the enzymatic complex of ATP-sulfurylase and firefly luciferase to generate photons from PPi. An enzymatic unity gain positive feedback is also implemented to regenerate the photon generation process and compensate any decay in light intensity by self regulation. Due to this positive feedback, the total number of photons generated by the bioluminescence regenerative cycle (BRC) can potentially be orders of magnitude higher than typical chemiluminescent processes. A system level kinetic model that incorporates the effects of contaminations and detector noise was used to show that the photon generation process is in fact steady and also proportional to the nucleic acid quantity. Here we show that BRC is capable of detecting quantities of DNA as low as 1 amol (10-18 mole) in 40μlit aqueous solutions, and this enzymatic assay has a controllable dynamic range of 5 orders of magnitude. The sensitivity of this technology, due to the excess number of photons generated by the regenerative cycle, is not constrained by detector performance, but rather by possible PPi or ATP (adenosine triphosphate) contamination, or background bioluminescence of the enzymatic complex.

  11. Real-time single-molecule imaging of quantum interference.

    Juffmann, Thomas; Milic, Adriana; Müllneritsch, Michael; Asenbaum, Peter; Tsukernik, Alexander; Tüxen, Jens; Mayor, Marcel; Cheshnovsky, Ori; Arndt, Markus

    2012-05-01

    The observation of interference patterns in double-slit experiments with massive particles is generally regarded as the ultimate demonstration of the quantum nature of these objects. Such matter-wave interference has been observed for electrons, neutrons, atoms and molecules and, in contrast to classical physics, quantum interference can be observed when single particles arrive at the detector one by one. The build-up of such patterns in experiments with electrons has been described as the "most beautiful experiment in physics". Here, we show how a combination of nanofabrication and nano-imaging allows us to record the full two-dimensional build-up of quantum interference patterns in real time for phthalocyanine molecules and for derivatives of phthalocyanine molecules, which have masses of 514 AMU and 1,298 AMU respectively. A laser-controlled micro-evaporation source was used to produce a beam of molecules with the required intensity and coherence, and the gratings were machined in 10-nm-thick silicon nitride membranes to reduce the effect of van der Waals forces. Wide-field fluorescence microscopy detected the position of each molecule with an accuracy of 10 nm and revealed the build-up of a deterministic ensemble interference pattern from single molecules that arrived stochastically at the detector. In addition to providing this particularly clear demonstration of wave-particle duality, our approach could also be used to study larger molecules and explore the boundary between quantum and classical physics. PMID:22447163

  12. Time-resolved computed tomography of the liver: retrospective, multi-phase image reconstruction derived from volumetric perfusion imaging

    To assess feasibility and image quality (IQ) of a new post-processing algorithm for retrospective extraction of an optimised multi-phase CT (time-resolved CT) of the liver from volumetric perfusion imaging. Sixteen patients underwent clinically indicated perfusion CT using 4D spiral mode of dual-source 128-slice CT. Three image sets were reconstructed: motion-corrected and noise-reduced (MCNR) images derived from 4D raw data; maximum and average intensity projections (time MIP/AVG) of the arterial/portal/portal-venous phases and all phases (total MIP/ AVG) derived from retrospective fusion of dedicated MCNR split series. Two readers assessed the IQ, detection rate and evaluation time; one reader assessed image noise and lesion-to-liver contrast. Time-resolved CT was feasible in all patients. Each post-processing step yielded a significant reduction of image noise and evaluation time, maintaining lesion-to-liver contrast. Time MIPs/AVGs showed the highest overall IQ without relevant motion artefacts and best depiction of arterial and portal/portal-venous phases respectively. Time MIPs demonstrated a significantly higher detection rate for arterialised liver lesions than total MIPs/AVGs and the raw data series. Time-resolved CT allows data from volumetric perfusion imaging to be condensed into an optimised multi-phase liver CT, yielding a superior IQ and higher detection rate for arterialised liver lesions than the raw data series. (orig.)

  13. Time-resolved computed tomography of the liver: retrospective, multi-phase image reconstruction derived from volumetric perfusion imaging

    Fischer, Michael A.; Kartalis, Nikolaos; Aspelin, Peter; Albiin, Nils; Brismar, Torkel B. [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Leidner, Bertil; Svensson, Anders [Karolinska University Hospital, Division of Medical Imaging and Technology, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm (Sweden); Karolinska University Hospital Huddinge, Department of Radiology, Stockholm (Sweden)

    2014-01-15

    To assess feasibility and image quality (IQ) of a new post-processing algorithm for retrospective extraction of an optimised multi-phase CT (time-resolved CT) of the liver from volumetric perfusion imaging. Sixteen patients underwent clinically indicated perfusion CT using 4D spiral mode of dual-source 128-slice CT. Three image sets were reconstructed: motion-corrected and noise-reduced (MCNR) images derived from 4D raw data; maximum and average intensity projections (time MIP/AVG) of the arterial/portal/portal-venous phases and all phases (total MIP/ AVG) derived from retrospective fusion of dedicated MCNR split series. Two readers assessed the IQ, detection rate and evaluation time; one reader assessed image noise and lesion-to-liver contrast. Time-resolved CT was feasible in all patients. Each post-processing step yielded a significant reduction of image noise and evaluation time, maintaining lesion-to-liver contrast. Time MIPs/AVGs showed the highest overall IQ without relevant motion artefacts and best depiction of arterial and portal/portal-venous phases respectively. Time MIPs demonstrated a significantly higher detection rate for arterialised liver lesions than total MIPs/AVGs and the raw data series. Time-resolved CT allows data from volumetric perfusion imaging to be condensed into an optimised multi-phase liver CT, yielding a superior IQ and higher detection rate for arterialised liver lesions than the raw data series. (orig.)

  14. Real-time synthetic aperture imaging: opportunities and challenges

    Nikolov, Svetoslav; Tomov, Borislav Gueorguiev; Jensen, Jørgen Arendt

    Synthetic aperture (SA) ultrasound imaging has not been introduced in commercial scanners mainly due to the computational cost associated with the hardware implementation of this imaging modality. SA imaging redefines the term beamformed line. Since the acquired information comes from all points in...... the region of interest it is possible to beamform the signals along a desired path, thus, improving the estimation of blood flow. The transmission of coded excitations makes it possible to achieve higher contrast and larger penetration depth compared to "conventional" scanners. This paper presents the...

  15. Resources of Digital FIR Filters Hardware Implementation in FPGAs for Digital Image Processing in Real Time

    Peter Cvicela; Josef Huska; Peter Kulla

    2004-01-01

    The main image information content, from the human visual system viewing point, is focused into whole colorimetric and spatial informations. Because every image is result of some previous processes, the goal for all standard image processing methods is improvement colorimetric and spatial image parameters in relation maximum information content by the complicated and expensive systems for digital image processing in (quasi)real time [1] based on the flash signal (multi)processors. Some single...

  16. Reporter cell activity within hydrogel constructs quantified from oxygen-independent bioluminescence.

    Lambrechts, Dennis; Roeffaers, Maarten; Kerckhofs, Greet; Hofkens, Johan; Van de Putte, Tom; Schrooten, Jan; Van Oosterwyck, Hans

    2014-09-01

    By providing a three-dimensional (3D) support to cells, hydrogels offer a more relevant in vivo tissue-like environment as compared to two-dimensional cell cultures. Hydrogels can be applied as screening platforms to investigate in 3D the role of biochemical and biophysical cues on cell behaviour using bioluminescent reporter cells. Gradients in oxygen concentration that result from the interplay between molecular transport and cell metabolism can however cause substantial variability in the observed bioluminescent reporter cell activity. To assess the influence of these oxygen gradients on the emitted bioluminescence for various hydrogel geometries, a combined experimental and modelling approach was implemented. We show that the applied model is able to predict oxygen gradient independent bioluminescent intensities which correlate better to the experimentally determined viable cell numbers, as compared to the experimentally measured bioluminescent intensities. By analysis of the bioluminescence reaction dynamics we obtained a quantitative description of cellular oxygen metabolism within the hydrogel, which was validated by direct measurements of oxygen concentration within the hydrogel. Bioluminescence peak intensities can therefore be used as a quantitative measurement of reporter cell activity within a hydrogel, but an unambiguous interpretation of these intensities requires a compensation for the influence of cell-induced oxygen gradients on the luciferase activity. PMID:24957291

  17. Rad Hard Imaging Array with Picosecond Timing Project

    National Aeronautics and Space Administration — For a wide range of remote sensing applications, there is a critical need to develop imaging arrays that simultaneously achieve high spatial resolution, high...

  18. Quorum Sensing Influences Vibrio harveyi Growth Rates in a Manner Not Fully Accounted For by the Marker Effect of Bioluminescence

    Nackerdien, Zeena E.; Keynan, Alexander; Bassler, Bonnie L.; Lederberg, Joshua; Thaler, David S.

    2008-01-01

    Background The light-emitting Vibrios provide excellent material for studying the interaction of cellular communication with growth rate because bioluminescence is a convenient marker for quorum sensing. However, the use of bioluminescence as a marker is complicated because bioluminescence itself may affect growth rate, e.g. by diverting energy. Methodology/Principal Findings The marker effect was explored via growth rate studies in isogenic Vibrio harveyi (Vh) strains altered in quorum sensing on the one hand, and bioluminescence on the other. By hypothesis, growth rate is energy limited: mutants deficient in quorum sensing grow faster because wild type quorum sensing unleashes bioluminescence and bioluminescence diverts energy. Findings reported here confirm a role for bioluminescence in limiting Vh growth rate, at least under the conditions tested. However, the results argue that the bioluminescence is insufficient to explain the relationship of growth rate and quorum sensing in Vh. A Vh mutant null for all genes encoding the bioluminescence pathway grew faster than wild type but not as fast as null mutants in quorum sensing. Vh quorum sensing mutants showed altered growth rates that do not always rank with their relative increase or decrease in bioluminescence. In addition, the cell-free culture fluids of a rapidly growing Vibrio parahaemolyticus (Vp) strain increased the growth rate of wild type Vh without significantly altering Vh's bioluminescence. The same cell-free culture fluid increased the bioluminescence of Vh quorum mutants. Conclusions/Significance The effect of quorum sensing on Vh growth rate can be either positive or negative and includes both bioluminescence-dependent and independent components. Bioluminescence tends to slow growth rate but not enough to account for the effects of quorum sensing on growth rate. PMID:18301749

  19. Real time 2 dimensional detector for charged particle and soft X-ray images

    The conventional instruments used in experiments for the soft X-ray region such as X-ray diffraction analysis are X-ray films or imaging plates. However, these instruments are not suitable for real time observation. In this paper, newly developed imaging devices will be presented, which have the capability to take X-ray images in real time with a high detection efficiency. Also, another capability, to take elementary particle tracking images, is described. (orig.)

  20. Image hiding in time-averaged deformable moiré gratings

    A new image hiding technique based on time-averaged moiré fringes is proposed in this paper. The secret image is embedded into a single cover image which is constructed as a deformable stochastic moiré grating. The secret image is leaked in the form of a time-averaged fringe when the cover image is deformed according to a predetermined periodic law of motion. The proposed image hiding approach opens new possibilities for the optical control of vibrating deformable structures. (paper)