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In Vivo Bioluminescent Imaging (BLI): Noninvasive Visualization and Interrogation of Biological Processes in Living Animals  [PDF]
Dan M. Close,Tingting Xu,Gary S. Sayler,Steven Ripp
Sensors , 2011, DOI: 10.3390/s110100180
Abstract: 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.
Living with “problem” animals
Coralie Mounet
Revue de Géographie Alpine , 2009, DOI: 10.4000/rga.560
Abstract: The presence and recent spread of the wolf and the boar in the mountains of the French Alps are upsetting the organisation of territorial “vivre ensemble” (cohabitation) projects. This article examines how this new situation is being dealt with at the local level and attempts to redefine local life between men and animals. The macro-social approach often adopted in analysing conflicts surrounding “problem” animals is considered to be insufficient and the article attempts to complement this by proposing a micro-geographical perspective that seeks to determine the logic underpinning actors’ behaviour, which until now has been inaccessible. It thus focuses on the role of variability in local situations. La présence ou le développement récent du loup et du sanglier dans les montagnes des Alpes fran aises viennent bouleverser l’organisation des vivre ensemble territoriaux. Cet article s’intéresse à l’intégration de cette nouvelle donne dans les territoires et à la redéfinition de la vie locale, entre hommes et animaux. L’approche macrosociale qui a souvent été retenue dans l’analyse des conflits autour des animaux à problème est considérée comme insuffisante et l’article tente de la compléter par un regard microgéographique, mettant en lumière des logiques d’acteurs inaccessibles jusqu’à présent. Il porte ainsi son attention sur la part de variabilité des situations locales.
Monitoring Therapeutic Treatments against Burkholderia Infections Using Imaging Techniques  [PDF]
Tiffany M. Mott,R. Katie Johnston,Sudhamathi Vijayakumar,D. Mark Estes,Massoud Motamedi,Elena Sbrana,Janice J. Endsley,Alfredo G. Torres
Pathogens , 2013, DOI: 10.3390/pathogens2020383
Abstract: 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.
Illumination of Parainfluenza Virus Infection and Transmission in Living Animals Reveals a Tissue-Specific Dichotomy  [PDF]
Crystal W. Burke equal contributor,John N. Mason equal contributor,Sherri L. Surman,Bart G. Jones,Emilie Dalloneau,Julia L. Hurwitz,Charles J. Russell
PLOS Pathogens , 2011, DOI: 10.1371/journal.ppat.1002134
Abstract: The parainfluenza viruses (PIVs) are highly contagious respiratory paramyxoviruses and a leading cause of lower respiratory tract (LRT) disease. Since no vaccines or antivirals exist, non-pharmaceutical interventions are the only means of control for these pathogens. Here we used bioluminescence imaging to visualize the spatial and temporal progression of murine PIV1 (Sendai virus) infection in living mice after intranasal inoculation or exposure by contact. A non-attenuated luciferase reporter virus (rSeV-luc(M-F*)) that expressed high levels of luciferase yet was phenotypically similar to wild-type Sendai virus in vitro and in vivo was generated to allow visualization. After direct intranasal inoculation, we unexpectedly observed that the upper respiratory tract (URT) and trachea supported robust infection under conditions that result in little infection or pathology in the lungs including a low inoculum of virus, an attenuated virus, and strains of mice genetically resistant to lung infection. The high permissivity of the URT and trachea to infection resulted in 100% transmission to na?ve contact recipients, even after low-dose (70 PFU) inoculation of genetically resistant BALB/c donor mice. The timing of transmission was consistent with the timing of high viral titers in the URT and trachea of donor animals but was independent of the levels of infection in the lungs of donors. The data therefore reveals a disconnect between transmissibility, which is associated with infection in the URT, and pathogenesis, which arises from infection in the lungs and the immune response. Natural infection after transmission was universally robust in the URT and trachea yet limited in the lungs, inducing protective immunity without weight loss even in genetically susceptible 129/SvJ mice. Overall, these results reveal a dichotomy between PIV infection in the URT and trachea versus the lungs and define a new model for studies of pathogenesis, development of live virus vaccines, and testing of antiviral therapies.
Bioluminescence Imaging of DNA Synthetic Phase of Cell Cycle in Living Animals  [PDF]
Zhi-Hong Chen, Rui-Jun Zhao, Rong-Hui Li, Cui-Ping Guo, Guo-Jun Zhang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0053291
Abstract: Bioluminescence reporter proteins have been widely used in the development of tools for monitoring biological events in living cells. Currently, some assays like flow cytometry analysis are available for studying DNA synthetic phase (S-phase) targeted anti-cancer drug activity in vitro; however, techniques for imaging of in vivo models remain limited. Cyclin A2 is known to promote S-phase entry in mammals. Its expression levels are low during G1-phase, but they increase at the onset of S-phase. Cyclin A2 is degraded during prometaphase by ubiquitin-dependent, proteasome-mediated proteolysis. In this study, we have developed a cyclin A2-luciferase (CYCA-Luc) fusion protein targeted for ubiquitin-proteasome dependent degradation, and have evaluated its utility in screening S-phase targeted anti-cancer drugs. Similar to endogenous cyclin A2, CYCA-Luc accumulates during S-phase and is degraded during G2/M-phase. Using Cdc20 siRNA we have demonstrated that Cdc20 can mediate CYCA-Luc degradation. Moreover, using noninvasive bioluminescent imaging, we demonstrated accumulation of CYCA-Luc in response to 10-hydroxycamptothecin (HCPT), an S-phase targeted anti-cancer drug, in human tumor cells in vivo and in vitro. Our results indicate that a CYCA-Luc fusion reporter system can be used to monitor S-phase of cell cycle, and evaluate pharmacological activity of anti-cancer drug HCPT in real time in vitro and in vivo, and is likely to provide an important tool for screening such drugs.
Advanced Concepts in Diagnosis of Hydatidosis in Human and Living Animals
Maha A. Sabry
Journal of Biological Sciences , 2007,
Abstract: Fractionation of fertile Hydatid cyst fluid antigens (FHCFA) revealed 12 protein fractions at molecular weights (MW) of 105, 79, 62, 49, 38 28 24 21, 18, 8 and 2 kD bands over 105 kD. The bands at MW of 38, 36, 29 18, 16, 12 and 8 kD were reacted specifically with sera of Hydatid Crabbits as well as sera of surgically proved HC infected patients using enzyme linked immuno-transfer blot (EITB) technique. Evaluating the diagnostic efficacy of 3 eluted concentrated sub units of these antigens at MW range of 32-38, 16-18 and 8-12 kD, revealed that the fractions in the range of 8-12 kD appear as the most specific (96.66%) fractions. It didn`t cross reacted with anti bodies (Ab) in sera of patients infected by Fasciola, gastro-intestinal nematodes (G. I. N.) infected camel as well as Fasciola and Moneizia infected sheep. It clear mild level of cross reaction (10%) with Virus hepatitis C and Schistosoma manson infected patients sera. These fractions appear more sensitive (100%) for diagnosis of anti HC Ab in sera of surgically proved HC infected patients, HC infected camels and HC experimentally infected rabbits using ELISA technique. Fertile Hydatid cyst fluid antigen (FHCFA) of 32-38 kD appear less specific (93.33%) than the fraction of (8-12 kD), but this fraction still has absolute sensitivity (100%). The last groups of bands (16-18 kD) appear as the lowest specific (81.66%) and sensitive (92.0%) one. The protein fractions in the range of 8-12 kD showing marked diagnostic efficacy for hydatidosis infection in random samples of exposed people and pre-slaughtered animals. Diagnosis of infection by ELISA technique was closely related to diagnosis using sonographic examination in human and post mortem examination in animals. So that the former group of antigens identified as a good tool for diagnosis of the disease in human and investigation to infection status in living animals, the matter which is essential to improve the prognosis of the infected patients and breeding valuable animals.
Massimo Filippi
Erciyes Medical Journal , 2002,
Abstract: Conventional magnetic resonance imaging (cMRI) is widely used for diagnosing multiple sclerosis (MS) and as a paraclinical tool to monitor disease activity and evolution in natural history studies and clinical trials. However, the correlation between cMRI and clinical findings is far from being strict. Among the reasons for this "clinical-MRI paradox", a major role has been attributed to the limited specificity of cMRI to the heterogeneous pathological substrates of MS and to its inability to quantify the extent of damage in the normalappearing tissues. Modern quantitative MR techniques have the potential to overcome some of the limitations of cMRI. Metrics derived from magnetization transfer and diffusion-weighted MRI enable us to quantify the extent of structural changes occurring within and outside macroscopic MS lesions with increased pathological specificity over cMRI. MR spectroscopy can add information on the biochemical nature of such changes, with the potential to improve significantly our ability to monitor inflammatory demyelination and axonal injury. Finally, functional MRI might provide new insights into the role of cortical adaptive changes in limiting the clinical consequences of white matter structural damage. Although the application of modern MR techniques is changing dramatically our understanding of how MS causes irreversible disability, their use for clinical trial monitoring is still very limited. Whereas there is increasing perception that modern quantitative MR techniques should be more extensively employed in clinical trials to advance the understanding of MS and derive innovative information, their use in clinical practice should still be regarded as premature.
Application of Bioluminescence Imaging for In Vivo Monitoring of Fungal Infections  [PDF]
Matthias Brock
International Journal of Microbiology , 2012, DOI: 10.1155/2012/956794
Abstract: Fungi can cause severe invasive infections especially in the immunocompromised host. Patient populations at risk are increasing due to ongoing developments in cancer treatment and transplantation medicine. Only limited diagnostic tools and few antifungals are available, rendering a significant number of invasive fungal infections life threatening. To reduce mortality rates, a better understanding of the infection processes is urgently required. Bioluminescence imaging (BLI) is a powerful tool for such purposes, since it allows visualisation of temporal and spatial progression of infections in real time. BLI has been successfully used to monitor infections caused by various microorganisms, in particular bacteria. However, first studies have also been performed on the fungi Candida albicans and Aspergillus fumigatus. Although BLI was, in principle, suitable to study the infection process, some limitations remained. Here, different luciferase systems are introduced, and current approaches are summarised. Finally, suggestions for further improvements of BLI to monitor fungal infections are provided. 1. Introduction Bioluminescence imaging (BLI) is a noninvasive technique that can be used to track microorganisms in living animals. To use this technique cells are generated that emit light from enzyme-catalysed oxidation reactions. Light emission is detected by highly sensitive charged coupled device (CCD) cameras that allow the collection of single photons [1]. The light-generating enzymes are generally called luciferases, although several different luciferases from a wide variety of organisms and without structural relatedness are known [2]. Nevertheless, all characterised luciferases have in common that they need oxygen for the light-emitting reaction but use different substrates and cofactors and emit light at different wavelengths. A short summary of key features of some frequently used luciferases that will be described in more detail is shown in Table 1. Table 1: Key features of selected luciferases from different phylogenetic origins. BLI has been used to monitor gene expression and disease progression caused by pathogenic bacteria [3]. Furthermore, the system has also been applied to monitor growth of implanted tumour cells for investigating the effectiveness of therapeutic approaches [4, 5]. In terms of eukaryotic microorganisms such as fungi, bioluminescence imaging has mainly been used for highly sensitive monitoring of gene expression [6, 7], whereas infection studies on fungi are basically limited to the dimorphic yeast Candida albicans [8, 9]
MICE, a program to track and monitor animals in animal facilities
Kim E Boulukos, Philippe Pognonec
BMC Genetics , 2001, DOI: 10.1186/1471-2156-2-4
Abstract: This program consists of a virtual facility in which scientists can perform all the tasks done in the real world (i.e., receiving animals, breeding them, preparing cage labels, etc.). Recording of each animal (birth date, cage number, ID number, tail analysis number, parents, genetic status, genetic background, etc.) enables reliable tracking. According to any parameter of interest, animals can then be identified, grouped, sorted, moved, and so forth. Crossings are automatically processed by the program. For example, new genetic backgrounds, generation number, and anticipated due dates are determined. The program also reminds the user when new births are expected and entering newborn animals only requires a few clicks. The genealogy of each animal can be determined in two different ways, one being the visualization of a genealogical tree from which information of ancestors can be retrieved.This standalone program, that will be distributed free of charge to academic laboratories requesting a license, represents a new and valuable tool for all animal facility users, and permits simple and reliable tracking and retrieving of animals.A survey of laboratories working with mice revealed that, except for the very recent "Mousebase" [1], which runs only on Macintoshes and requires the purchase of a license for multiple user configuration, and expensive commercial programs, no convenient system exists to handle recording information of mouse in animal facilities in a reliable manner. When this information is conventionally stored in notebooks, the tracking of different animals becomes quite tedious. Some laboratories have developed computerized lists using word processing applications, allowing animal searches with the word processor "find" function. But accidental modifications are possible and animal tracking, sorting and genealogy determination are basically impossible to perform. In order to sanitize this situation plaguing the majority of laboratories, we developed MICE
Mechanical and free living comparisons of four generations of the Actigraph activity monitor  [cached]
Ried-Larsen Mathias,Br?nd Jan,Brage S?ren,Hansen Bj?rge
International Journal of Behavioral Nutrition and Physical Activity , 2012, DOI: 10.1186/1479-5868-9-113
Abstract: Background More studies include multiple generations of the Actigraph activity monitor. So far no studies have compared the output including the newest generation and investigated the impact on the output of the activity monitor when enabling the low frequency extension (LFE) option. The aims were to study the responses of four generations (AM7164, GT1M, GT3X and GT3X+) of the Actigraph activity monitor in a mechanical setup and a free living environment with and without enabling the LFE option. Methods The monitors were oscillated in a mechanical setup using two radii in the frequency range 0.25-3.0 Hz. Following the mechanical study a convenience sample (N = 20) wore three monitors (one AM7164 and two GT3X) for 24 hours. Results The AM7164 differed from the newer generations across frequencies (p < 0.05) in the mechanical setup. The AM7164 produced a higher output at the lower and at the highest intensities, whereas the output was lower at the middle intensities in the mid-range compared to the newer generations. The LFE option decreased the differences at the lower frequencies, but increased differences at the higher. In free living, the mean physical activity level (PA) of the GT3X was 18 counts per minute (CPM) (8%) lower compared to the AM7164 (p < 0.001). Time spent in sedentary intensity was 26.6 minutes (95% CI 15.6 to 35.3) higher when assessed by the GT3X compared to the AM7164 (p < 0.001). Time spend in light and vigorous PA were 23.3 minutes (95% CI 31.8 to 14.8) and 11.7 minutes (95% CI 2.8 to 0.7) lower when assessed by the GT3X compared to the AM7164 (p < 0.05). When enabling the LFE the differences in the sedentary and light PA intensity (<333 counts*10 sec-1) were attenuated (p > 0.05 for differences between generations) thus attenuated the difference in mean PA (p > 0.05) when the LFE option was enabled. However, it did not attenuate the difference in time spend in vigorous PA and it introduced a difference in time spend in moderate PA (+ 3.0 min (95% CI 0.4 to 5.6)) between the generations. Conclusion We observed significant differences between the AM7164 and the newer Actigraph GT-generations (GT1M, GT3X and GT3X+) in a mechanical setup and in free-living. Enabling the LFE option attenuated the differences in mean PA completely, but induced a bias in the moderate PA intensities.
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