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Molecular Imaging (molecular + imaging)
Kinds of Molecular Imaging Terms modified by Molecular Imaging Selected AbstractsCurrent Awareness in Contrast Media and Molecular ImagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 2 2010Article first published online: 20 APR 2010 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of Contrast Media and Molecular Imaging. Each bibliography is divided into 15 sections: 1 Reviews; 2 General; Contrast Agents: 3 Chemistry; 4 Technique; 5 Experimental; 6 Applications; Molecular Imaging: 7 Carbon; 8 Fluorine; 9 Gallium; 10 Hydrogen; 11 Indium; 12 Iodine; 13 Phosphorus; 14 Technetium; 15 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in Contrast Media and Molecular ImagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2010Article first published online: 22 FEB 2010 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of Contrast Media and Molecular Imaging. Each bibliography is divided into 15 sections: 1 Reviews; 2 General; Contrast Agents: 3 Chemistry; 4 Technique; 5 Experimental; 6 Applications; Molecular Imaging: 7 Carbon; 8 Fluorine; 9 Gallium; 10 Hydrogen; 11 Indium; 12 Iodine; 13 Phosphorus; 14 Technetium; 15 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in Contrast Media and Molecular ImagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2008Article first published online: 11 MAR 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of Contrast Media and Molecular Imaging. Each bibliography is divided into 15 sections: 1 Reviews; 2 General; Contrast Agents: 3 Chemistry; 4 Technique; 5 Experimental; 6 Applications; Molecular Imaging: 7 Carbon; 8 Fluorine; 9 Gallium; 10 Hydrogen; 11 Indium; 12 Iodine; 13 Phosphorus; 14 Technetium; 15 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Erratum: MR imaging in assessing cardiovascular interventions and myocardial injuryCONTRAST MEDIA & MOLECULAR IMAGING, Issue 2 2007Alexis Jacquier Contrast Media and Molecular Imaging, MR imaging in assessing cardiovascular interventions and myocardial injury, Alexis Jacquier, Charles B. Higgins and Maythem Saeed, published in CMMI 2:1, DOI: 10.1002/cmmi122, pp1,15. Contract/Grant Sponsor information relating to Dr. A. Jacquier was absent from the published article. It should be noted that Dr. A. Jacquier was supported by the Société Française de Radiologie, Paris, as a research fellow. [source] Current Awareness in Contrast Media and Molecular ImagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 6 2006Article first published online: 8 DEC 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of Contrast Media and Molecular Imaging. Each bibliography is divided into 15 sections: 1 Reviews; 2 General; Contrast Agents: 3 Chemistry; 4 Technique; 5 Experimental; 6 Applications; Molecular Imaging: 7 Carbon; 8 Fluorine; 9 Gallium; 10 Hydrogen; 11 Indium; 12 Iodine; 13 Phosphorus; 14 Technetium; 15 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Current Awareness in Contrast Media and Molecular ImagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 5 2006Article first published online: 10 OCT 200 In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of Contrast Media and Molecular Imaging. Each bibliography is divided into 15 sections: 1 Reviews; 2 General; Contrast Agents: 3 Chemistry; 4 Technique; 5 Experimental; 6 Applications; Molecular Imaging: 7 Carbon; 8 Fluorine; 9 Gallium; 10 Hydrogen; 11 Indium; 12 Iodine; 13 Phosphorus; 14 Technetium; 15 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted. [source] Why CMMI?,why a new journal on Contrast Media and Molecular Imaging?CONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2006Professor Silvio Aime [source] Molecular Imaging of Cancer Cells Using Plasmon-Resonant-Enhanced Third-Harmonic-Generation in Silver Nanoparticles,ADVANCED MATERIALS, Issue 24 2007S.-P. Tai We demonstrate molecule-specific third-harmonic-generation (THG) microscopy by using silver nanoparticles as THG contrast agents. Through matching surface plasmon wavelength to THG wavelength, strong contrast can be provided by silver nanoparticles under THG microscopy. By conjugating anti-her2 antibodies with silver nanoparticles, the expression of the Her2/neu oncogene in the cancer cell membranes is successfully imaged under THG modality for the first time. [source] Observations on the role of nuclear medicine in molecular imagingJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S39 2002D.J. Hnatowich Abstract The phrase "molecular imaging" is unquestionably current and is receiving ever increasing use. For example, two organizations, the Institute for Molecular Imaging and the Academy of Molecular Imaging have recently been established with molecular imaging as their focus, with journal entitled "Molecular Imaging" and "Molecular Imaging and Biology," respectively. Furthermore, the two leading journals in the field of nuclear medicine have recently added this phrase to their covers-becoming the "European Journal of Nuclear Medicine and Molecular Imaging" and "The Journal of Nuclear Medicine,advancing molecular imaging." The National Institute of Biomedical Imaging and Bioengineering is the newest institute of the NIH. With this degree of attention, it may be surprising that there is as yet no universally accepted definition of molecular imaging. Numerous diverse definitions, some quite complex, have been proposed. With some exceptions, they all refer to imaging in the living animal of function at the cellular or molecular level. Thus molecular imaging may be defined as the observation of biological function at the molecular level in health and disease through some process involving non-invasive imaging of the living mammals. J. Cell. Biochem. Suppl. 39: 18,24, 2002. © 2002 Wiley-Liss, Inc. [source] Scanning Imaging of Magnetic Nanoparticles for Quantitative Molecular Imaging,ANGEWANDTE CHEMIE, Issue 41 2010Dr. Li Yao Als molekulare Sonden binden markierte magnetische Nanopartikel (NPs) spezifisch an bestimmte Antikörper. Das Magnetfeld der gebundenen NPs wird durch Abrastern mit einem optischen Magnetometer detektiert, das auf den magneto-optischen Eigenschaften von Alkalimetallatomen beruht. Die Magnetisierung , und damit die Zahl der Antikörper-gebundenen magnetischen NPs , und die zugehörigen zweidimensionalen Informationen werden simultan erhalten. [source] Detection of Overexpressed COX-2 in Precancerous Lesions of Hamster Pancreas and Lungs by Molecular Imaging: Implications for Early Diagnosis and PreventionCHEMMEDCHEM, Issue 6 2006Hildegard Abstract The enzyme cyclooxygenase-2 (COX-2) is overexpressed in many cancers, cardiovascular disease, neurodegenerative disorders, and arthritis. Selective inhibitors of COX-2 have been developed as therapeutics or preventive agents for these diseases. However, recent reports have revealed a significant increase in cardiovascular mortality in long-term users of the COX-2 inhibitors Vioxx and Celebrex, emphasizing the need for noninvasive tests that allow the identification of individuals whose COX-2 levels are overexpressed prior to assignment to treatment with these drugs. In this study, we have prepared a radioiodinated analogue of the selective COX-2 inhibitor celecoxib, and verified its binding to the COX-2 enzyme in,vitro. Biodistribution studies in hamsters demonstrated significantly higher levels of radiotracer in animals treated with the tobacco carcinogen NNK in lung, pancreas, and liver. Assessment of COX-2 levels by whole-body planar nuclear imaging two hours after injection of the radiotracer was suggestive of a distinct increase in COX-2 in the pancreas and liver of a hamster treated for 10 weeks with NNK, in the lungs and liver of a second animal, and in the liver only, in two additional animals from the same treatment group. Immunostains showed selective overexpression of COX-2 in pre-neoplastic lesions of the pancreas and lungs in only those animals that showed tracer accumulation in these organs and in the livers of all NNK-treated hamsters. Immunostains for COX-1 yielded detectable reactions in the intestinal epithelium but not in pancreas, lungs, or liver, supporting the specificity of the tracer for COX-2. Our data provide proof of principle for the hypothesis that molecular imaging with radiolabeled COX-2 inhibitors can be used for the noninvasive monitoring of overexpressed COX-2 levels. [source] Molecular imaging in hereditary forms of parkinsonismEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2007M. C. Shih The development of in vivo molecular imaging to evaluate the dopamine (DA) system with positron-emission tomography and single photon emission computed tomography has been of key importance on monitoring in vivo nigrostriatal neuronal loss in Parkinson's disease (PD), mostly through assessments of pre- and post-synaptic DA receptors. The discoveries of genes related to hereditary forms of parkinsonism (PARK1, PARK2, PARK6, PARK7 and PARK8) have increased our understanding either of distinct subtypes of clinical expression in PD or its etiology. This article revises current data on molecular neuroimaging of genetic forms of parkinsonism comparing and contrasting its main features with the classical sporadic forms. Awareness of the spectrum variance in the genotype and its respective PD phenotype are useful to distinguish different pathophysiological mechanisms of PD. [source] Brain Imaging in Migraine ResearchHEADACHE, Issue 9 2010David Borsook MD Understanding the pathophysiology and pharmacology of migraine has been driven by astute clinical observations, elegant experimental medicine studies, and importantly by studying highly effective anti-migraine agents in the laboratory and the clinic. Significant progress has been made in the use of functional brain imaging to compliment observational studies of migraine phenotypes by highlighting pathways within the brain that may be involved in predisposition to migraine, modulating migraine pain or that could be sensitive to pharmacological or behavioral therapeutic intervention (Fig. 1). In drug discovery, molecular imaging approaches compliment functional neuroimaging by visualizing migraine drug targets within the brain. Molecular imaging enables the selection and evaluation of drug candidates by confirming that they engage their targets sufficiently at well tolerated doses to test our therapeutic hypotheses. Figure 1.,. Imaging and defining the migraine brain disease state: from anatomy to chemical entities (targets) to functional systems (function and pathways) (from Borsook et al31 with permission, Nature Publishing Group). Migraine is a progressive disorder. Developing our knowledge of where drugs act in the brain and of how the brain is altered in both episodic migraine (interictal state and ictal state) and chronic migraine are important steps to understanding why there is such differential responsiveness to therapeutics among migraine patients and to improving how they are evaluated and treated. [source] Molecular imaging: The latest generation of contrast agents and tissue characterization techniquesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2003Francis G. BlankenbergArticle first published online: 25 AUG 200 Abstract Molecular Imaging technologies will have a profound impact on both basic research and clinical imaging in the near future. As the field covers many different specialties and scientific disciplines it is not possible to review all in a single article. In the current article we will turn our attention to those modalities that are either currently in use or in development for the medical imaging clinic. © 2003 Wiley-Liss, Inc. [source] Molecular imaging of regional brain tumor biologyJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S39 2002A.M. Spence Abstract Energy metabolism measurements in gliomas in vivo are now performed widely with positron emission tomography (PET). This capability has developed from a large number of basic and clinical science investigations that have cross fertilized one another. This article presents several areas that exemplify questions that have been explored over the last two decades. While the application of PET with [18F]-2-fluoro-2-deoxyglucose (FDG-PET) has proven useful for grading and prognosis assessments, this approach is less clinically suitable for assessing response to therapy, even though results to date raise very intriguing biological questions. Integration of metabolic imaging results into glioma therapy protocols is a recent and only preliminarily tapped method that may prove useful in additional trials that target DNA or membrane biosynthesis, or resistance mechanisms such as hypoxia. There are exciting future directions for molecular imaging that will undoubtedly be fruitful to explore, especially apoptosis, angiogenesis and expression of mutations of genes, e.g., epidermal growth factor receptor, that promote or suppress cellular malignant behavior. J. Cell. Biochem. Suppl. 39: 25,35, 2002. © 2002 Wiley-Liss, Inc. [source] Molecular imaging: The application of small animal positron emission tomographyJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S39 2002Douglas J. Rowland Abstract The extraordinary advances in genomic technologies over the last decade have led to the establishment of new animal models of disease. The use of molecular imaging techniques to examine these models, preferably with non-destructive imaging procedures, such as those offered by positron emission tomography (PET), are especially valuable for the timely advancement of research. With the use of small animal PET imaging it is possible to follow individual subjects of a sample population over an extended time period by using highly specific molecular probes and radiopharmaceuticals. In this Prospect small animal PET imaging will be described, specifically focusing on the current technologies, its applications in molecular imaging and the logistics of performing small animal PET. J. Cell. Biochem. Suppl. 39: 110,115, 2002. © 2002 Wiley-Liss, Inc. [source] Molecular imaging in small animals,roles for micro-CTJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S39 2002Erik L. Ritman Abstract X-ray micro-CT is currently used primarily to generate 3D images of micro-architecture (and the function that can be deduced from it) and the regional distribution of administered radiopaque indicators, within intact rodent organs or biopsies from large animals and humans. Current use of X-ray micro-CT can be extended in three ways to increase the quantitative imaging of molecular transport and accumulation within such specimens. (1) By use of heavy elements, other than the usual iodine, attached to molecules of interest or to surrogates for those molecules. The accumulation of the indicator in the physiological compartments, and the transport to and from such compartments, can be quantitated from the imaged spatial distribution of these contrast agents. (2) The high spatial resolution of conventional X-ray attenuation-based CT images can be used to improve the quantitative nature of radionuclide-based tomographic images (SPECT & PET) by providing correction for attenuation of the emitted gamma rays and the accurate delineation of physiological spaces known to selectively accumulate those indicators. Similarly, other imaging modalities which also localize functions in 2D images (such as histological sections subsequently obtained from the same specimen), can provide a synergistic combination with CT-based 3D microstructure. (3) By increasing the sensitivity and specificity of X-ray CT image contrast by use of methods such as: K-edge subtraction imaging, X-ray fluorescence imaging, imaging of the various types of scattered X-ray and the consequences of the change in the speed of X-rays through different tissues, such as refraction and phase shift. These other methods of X-ray imaging can increase contrast by more than an order of magnitude over that due to conventionally-used attenuation of X-ray. To fully exploit their potentials, much development of radiopaque indicators, scanner hardware and image reconstruction and analysis software will be needed. J. Cell. Biochem. Suppl. 39: 116,124, 2002. © 2002 Wiley-Liss, Inc. [source] Synthesis of (R)- and (S)-[O-methyl - 11C]N -[2-[3-(2-cyano-phenoxy)-2-hydroxy-propylamino]-ethyl]- N,-(4-methoxy-phenyl)-urea as candidate high affinity ,1 -adrenoceptor PET radioligandsJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 10 2005Stefan Wagner Abstract Molecular imaging and quantification of myocardial ,1 -adrenoceptor (AR) rather than total , -AR density is of great clinical interest since cardiac biopsy studies suggest that myocardial ,1 -AR density is reduced in patients with chronic heart failure whereas cardiac ,2 -AR density may vary. Positron emission tomography (PET), with appropriate radioligands, offers the possibility to assess , -AR density non-invasively in humans. However, no PET radioligand for the selective imaging of cardiac ,1 -ARs is clinically available. Here some derivatives of the well characterized ,1 -AR selective antagonist, ICI 89,406, namely the enantiomers of N -[2-[3-(2-cyano-phenoxy)-2-hydroxy-propylamino]-ethyl]- N,-(4-hydroxy-phenyl)-urea (5a and 5b) were synthesized and evaluated in vitro. The (R)-isomer 5a was more ,1 -selective but has lower affinity than its (S)-enantiomer 5b (,1 -AR selectivity: 6100 vs 1240; ,1 -affinity: K1 = 0.288 nM vs K1 = 0.067 nM). Etherification of the analogous desmethyl precursors, 5e and 5f, respectively, with [11C]iodomethane gave 11C-labelled versions of 5a and 5b, namely 5g and 5h, in 44 ± 5% radiochemical yield (decay-corrected) and 97.4 ± 1.3% radiochemical purity with specific radioactivities of 26.4 ± 9.4 GBq/µmol within 41.2 ± 3.4 min from the end of bombardment (n = 14). 5g and 5h are now being evaluated as candidate radioligands for myocardial ,1 -ARs. Copyright © 2005 John Wiley & Sons, Ltd. [source] Molecular imaging for pediatric lung diseasesPEDIATRIC PULMONOLOGY, Issue 4 2004Jean-Christophe Richard MD Abstract Molecular imaging is a rapidly developing multidisciplinary field that combines advances in contrast agent development, instrumentation, and molecular/cell biology to follow cellular and sub-cellular events in intact organisms. Platforms for molecular imaging include radionuclide-based methods, optical methods, and magnetic resonance. To date, molecular imaging studies of the lungs have been used to monitor the effectiveness of gene transfer, neutrophilic inflammation, and cell trafficking. Eventually, the goal will be to translate these new techniques to clinical settings such as cystic fibrosis. Pediatr Pulmonol. 2004; 37:286,296. © 2004 Wiely-Liss, Inc. [source] Technoreview: Molecular imaging of host,pathogen interactions in intact small animalsCELLULAR MICROBIOLOGY, Issue 4 2004David Piwnica-Worms Summary Characterization and non-invasive measurement of host,pathogen interactions in living cells, animal models and humans at the cellular and molecular levels is now possible using remote imaging detectors. Positron emission tomography scanners, highly sensitive cooled charge-coupled device cameras for bioluminescence and fluorescence imaging as well as high-magnetic-field magnetic resonance imaging scanners can be used to study such diverse processes as pathogen tropism, pathogen life cycle, signal transduction, host response, cell trafficking and gene transfer. In many cases, images from more than one modality can be fused, allowing structure,function and multifunction relationships to be studied on a tissue-restricted or regional basis. These new instruments, when used in conjunction with targeted contrast agents, reporter substrates and radiopharmaceuticals, enable ,molecular imaging' with enormous potential for elucidating host,pathogen interactions in intact animal models. [source] Novel MRI and fluorescent probes responsive to the Factor XIII transglutaminase activityCONTRAST MEDIA & MOLECULAR IMAGING, Issue 4 2010Lorenzo Tei Abstract Transglutaminases, including factor XIII and tissue transglutaminase, participate in multiple extracellular processes associated with remodeling of the extracellular matrix during wound repair, blood clotting, tumor progression and fibrosis of ischemic injuries. The aim of this work was to evaluate a novel substrate analog for transglutaminase optimized by molecular modeling calculations (DCCP16), which can serve for molecular imaging of transglutaminase activity by magnetic resonance imaging and by near-infrared imaging. Experimental data showed covalent binding of Gd,DCCP16 and DCCP16-IRIS Blue to human clots, to basement membrane components and to casein in purified systems as well as in three-dimensional multicellular spheroids. In vivo, DCCP16 showed enhancement with a prolonged retention in clots and tumors, demonstrating the ability to detect both factor XIII and tissue transglutaminase mediated covalent binding of the contrast material. Copyright © 2010 John Wiley & Sons, Ltd. [source] Improved synthesis of DOTA tetraamide ligands for lanthanide(III) ions: A tool for increasing the repertoire of potential PARACEST contrast agents for MRI and/or fluorescent sensorsCONTRAST MEDIA & MOLECULAR IMAGING, Issue 3 2010Luis M. De León-Rodríguez Abstract The synthesis of new DOTA tetraamide (DOTAMR4) compounds is of great interest given their application in the formation of Ln(III) complexes as potential PARACEST contrast agents in MRI or fluorescent molecular probes. In this context amino acid and peptide DOTAMR4 derivatives are particularly attractive since the amino-acid and/or peptide moiety can show responsive properties dependent on a given stimuli which might translate to changes in water exchange rates of the corresponding Ln(III) complex. Current synthesis of DOTAMR4 derivatives is typically carried out by reacting haloacetamide intermediates with cyclen. However, this method fails to generate the tetra-substituted products when bulky substituents are present in the haloacetamide and in some cases this intermediate cannot be prepared by conventional acylation procedures limiting the number of DOTAMR4 compounds available for study. As a solution to these limitations, an improved methodology for the synthesis of DOTAMR4 by coupling DOTA to an appropriate amine containing reagent (i.e. protected amino-acids with the , -amino group free) is presented in this work. Several DOTAMR4 derivatives which are difficult or impossible to prepare with the traditional methodologies were easily obtained starting with DOTA. A new protocol was derived using this methodology for the solution-phase synthesis of DOTA peptide derivatives. With this methodology, many other DOTAMR4 peptide and non-peptide derivatives have been prepared in our laboratories with several of these new compounds showing interesting properties for molecular imaging. Copyright © 2010 John Wiley & Sons, Ltd. [source] Evaluation of rHA labeled with Gd,DTPA for blood pool imaging and targeted contrast deliveryCONTRAST MEDIA & MOLECULAR IMAGING, Issue 1 2010Jim M. Wild Abstract A new contrast agent was developed by linking Gd,DTPA chelate to recombinant human albumin in the laboratory. The molar relaxivity of the new agent was tested in aqueous solution at B0 1.5,T and temperature 20°C. The soluble compound had a higher molar longitudinal relaxivity and molar transverse relaxivity in water (r1,=,7.2,s,1,mM,1, r2,=,18.4,s,1,mM,1) than those measured for Gd,DTPA solution (r1,=,3.5,s,1,mM,1, r2,=,5.5,s,1,mM,1). The performance of the compound as a blood pool agent was investigated with soluble and microparticulate forms of the compound and comparisons were made with Gd,DTPA and the polymeric blood-pool agent, Gadomer. T1 -weighted imaging experiments show that the soluble compound acts as a highly effective blood pool agent with hyperintensity in the vasculature persisting beyond 2,h post administration, compared with free Gd,DTPA, which was cleared from the blood pool after approximately 10,min. The clearance kinetics of the new agents were examined, due to the incomplete elimination within 14 days post injection; both rHA labeled compounds are probably not suitable for development as routine blood pool contrast media. However, with free sites on the Gd-loaded rHA molecule, there are possibilities for binding the agent to antibodies in the laboratory, which was demonstrated, and thus there exist potential applications for in vivo molecular imaging with this agent. Copyright © 2010 John Wiley & Sons, Ltd. [source] CMR2009: 9.04: Multicolored (spectral) CT molecular imaging: the next step in CT imagingCONTRAST MEDIA & MOLECULAR IMAGING, Issue 6 2009D. Pan No abstract is available for this article. [source] Kinetic analysis of hyaluronidase activity using a bioactive MRI contrast agentCONTRAST MEDIA & MOLECULAR IMAGING, Issue 3 2006Liora Shiftan Abstract One of the attractions of molecular imaging using ,smart' bioactive contrast agents is the ability to provide non-invasive data on the spatial and temporal changes in the distribution and expression patterns of specific enzymes. The tools developed for that aim could potentially also be developed for functional imaging of enzyme activity itself, through quantitative analysis of the rapid dynamics of enzymatic conversion of these contrast agents. High molecular weight hyaluronan, the natural substrate of hyaluronidase, is a major antiangiogenic constituent of the extracellular matrix. Degradation by hyaluronidase yields low molecular weight fragments, which are proangiogenic. A novel contrast material, HA-GdDTPA-beads, was designed to provide a substrate analog of hyaluronidase in which relaxivity changes are induced by enzymatic degradation. We show here a first-order kinetic analysis of the time-dependent increase in R2 as a result of hyaluronidase activity. The changes in R2 and the measured relaxivity of intact HA-GdDTPA-beads (r2B) and HA-GdDTPA fragments (r2D) were utilized for derivation of the temporal drop in concentration of GdDTPA in HA-GdDTPA-beads as the consequence of the release of HA-GdDTPA fragments. The rate of dissociation of HA-GdDTPA from the beads showed typical bell-shaped temperature dependence between 7 and 36 °C with peak activity at 25 °C. The tools developed here for quantitative dynamic analysis of hyaluronidase activity by MRI would allow the use of activation of HA-GdDTPA-beads for the determination of the role of hyaluronidase in altering the angiogenic microenvironment of tumor micro metastases. Copyright © 2006 John Wiley & Sons, Ltd. [source] Molecular imaging in hereditary forms of parkinsonismEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2007M. C. Shih The development of in vivo molecular imaging to evaluate the dopamine (DA) system with positron-emission tomography and single photon emission computed tomography has been of key importance on monitoring in vivo nigrostriatal neuronal loss in Parkinson's disease (PD), mostly through assessments of pre- and post-synaptic DA receptors. The discoveries of genes related to hereditary forms of parkinsonism (PARK1, PARK2, PARK6, PARK7 and PARK8) have increased our understanding either of distinct subtypes of clinical expression in PD or its etiology. This article revises current data on molecular neuroimaging of genetic forms of parkinsonism comparing and contrasting its main features with the classical sporadic forms. Awareness of the spectrum variance in the genotype and its respective PD phenotype are useful to distinguish different pathophysiological mechanisms of PD. [source] Triplex Au,Ag,C Core,Shell Nanoparticles as a Novel Raman LabelADVANCED FUNCTIONAL MATERIALS, Issue 6 2010Aiguo Shen Abstract Monodispersed, readily-grafted, and biocompatible surface-enhanced Raman spectroscopic (SERS) tagging materials are developed; they are composed of bimetallic Au@Ag nanoparticles (NPs) for optical enhancement, a reporter molecule for spectroscopic signature, and a carbon shell for protection and bioconjugation. A controllable and convenient hydrothermal synthetic route is presented to synthesize the layer-by-layer triplex Au,Ag,C core,shell NPs, which can incorporate the Raman-active label 4-mercapto benzoic acid (4-MBA). The obtained gold seed,silver coated particles can be coated further with a thickness-controlled carbon shell to form colloidal carbon-encapsulated Aucore/Agshell spheres with a monodisperse size distribution. Furthermore, these SERS-active spheres demonstrated interesting properties as a novel Raman tag for quantitative immunoassays. The results suggest such SERS tags can be used for multiplex and ultrasensitive detection of biomolecules as well as nontoxic, in vivo molecular imaging of animal or plant tissues. [source] New Generation of Multifunctional Nanoparticles for Cancer Imaging and TherapyADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Kyeongsoon Park Abstract Advances in nanotechnology have contributed to the development of novel nanoparticles that enable the tumor-specific delivery of imaging probes and therapeutic agents in cancer imaging and therapy. Nanobiotechnology combines nanotechnology with molecular imaging, which has led to the generation of new multifunctional nanoparticles for cancer imaging and therapy. Multifunctional nanoparticles hold great promise for the future of cancer treatment because they can detect the early onset of cancer in each individual patient and deliver suitable therapeutic agents to enhance therapeutic efficacy. The combination of tumor-targeted imaging and therapy in an all-in-one system provides a useful multimodal approach in the battle against cancer. Novel multifunctional nanoparticles thus offer a new avenue in the application of personalized medicine in the near future. Herein, new trends and the significance of novel multifunctional nanoparticles in cancer imaging and therapy are reviewed. [source] Computational methods for optical molecular imagingINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 12 2009Duan Chen Abstract A new computational technique, the matched interface and boundary (MIB) method, is presented to model the photon propagation in biological tissue for the optical molecular imaging. Optical properties have significant differences in different organs of small animals, resulting in discontinuous coefficients in the diffusion equation model. Complex organ shape of small animal induces singularities of the geometric model as well. The MIB method is designed as a dimension splitting approach to decompose a multidimensional interface problem into one-dimensional ones. The methodology simplifies the topological relation near an interface and is able to handle discontinuous coefficients and complex interfaces with geometric singularities. In the present MIB method, both the interface jump condition and the photon flux jump conditions are rigorously enforced at the interface location by using only the lowest-order jump conditions. This solution near the interface is smoothly extended across the interface so that central finite difference schemes can be employed without the loss of accuracy. A wide range of numerical experiments are carried out to validate the proposed MIB method. The second-order convergence is maintained in all benchmark problems. The fourth-order convergence is also demonstrated for some three-dimensional problems. The robustness of the proposed method over the variable strength of the linear term of the diffusion equation is also examined. The performance of the present approach is compared with that of the standard finite element method. The numerical study indicates that the proposed method is a potentially efficient and robust approach for the optical molecular imaging. Copyright © 2008 John Wiley & Sons, Ltd. [source] Transplantation of human embryonic stem cell-derived endothelial cells for vascular diseasesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2009Zongjin Li Abstract Using endothelial cells for therapeutic angiogenesis/vasculogenesis of ischemia diseases has led to exploring human embryonic stem cells (hESCs) as a potentially unlimited source for endothelial progenitor cells. With their capacity for self-renewal and pluripotency, hESCs and their derived endothelial cells (hESC-ECs) may be more advantageous than other endothelial cells obtained from diseased populations. However, hESC-ECs' poor differentiation efficiency and poorly characterized in vivo function after transplantation present significant challenges for their future clinical application. This review will focus on the differentiation pathways of hESCs and their therapeutic potential for vascular diseases, as well as the monitoring of transplanted cells' fate via molecular imaging. Finally, cell enhancement strategies to improve the engraftment efficiency of hESC-ECs will be discussed. J. Cell. Biochem. 106: 194,199, 2009. © 2008 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||