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Imaging Technology (imaging + technology)
Kinds of Imaging Technology Selected AbstractsExpertise in Imaging TechnologyIMAGING & MICROSCOPY (ELECTRONIC), Issue 3 2009Martin Bossard Sometimes it is very difficult to decide what you really need. There is a large number of manufacturers for each available product. Especially if the product is expensive and the purposes are sophisticated, there is a high risk to purchase a product that has much more capacities than needed, or even the wrong ones. [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] Premotor Parkinson's disease: Clinical features and detection strategies,MOVEMENT DISORDERS, Issue S2 2009Randolph Stephenson MD Abstract In many areas of medicine, the focus has shifted from treating existing disease to screening and prevention. The technology to screen for Parkinson's disease (PD) already exists. The current challenge is to define the appropriate use of predictive testing for PD. Imaging technologies currently offer the highest degree of accuracy for identifying premotor PD, but they are expensive as screening tools. Efficiency is greatly enhanced by combining imaging with a prescreening test, such as olfactory testing. This two-step process has the potential to greatly reduce costs while retaining diagnostic accuracy. Ultimately, the role of preclinical detection of PD will be determined by the ability of emerging therapies to influence clinical outcomes. As such, implementation of large-scale screening strategies awaits the arrival of clearly safe and effective therapies that address the underlying pathogenesis of PD. Current research to evaluate efficient screening methods and to understand the clinical and physiological features of "premotor" PD will lay the foundation for the screening and prevention strategies of the future. © 2008 Movement Disorder Society [source] Imaging technology of the futureBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 10 2006A. Persson Expectation of imaging-based treatments [source] Micro-focus X-ray computed tomography images of the 3D structure of the cranium of a fetus with asymmetric double malformationCONGENITAL ANOMALIES, Issue 1 2006Takashi Shibata ABSTRACT,, Reconstructed micro computed tomography (Micro-CT, µ-CT) images have revealed the detailed three-dimensional structure of the cranium of human fetal congenital anomalies for the first time. The objects were a head and a cervix of female autosite and a parasite consisting of only a head conjoined to the scapular region of the autosite of an asymmetric double malformation (asymmetric conjoined twins, heteropagus twinning) at a gestational age of 8 months. The cranium of the autosite was normal, but that of the parasite was characterized by otocephaly (agnathia, synotia, and monorhina) and almost all the cranial bones were of an abnormal shape. It is suggested that a part of occipital bone (the basioccipital and exoccipital bones), the vomer and cribriform plate were absent and this resulted in the fusion and overlapping of bilateral temporal and craniofacial bones that should have been adjacent to them. This resulted in a reformation and relocation of most of the cranial bones. Micro-CT is a useful tool to visualize the detailed bone structure which has not been clarified by the conventional dissection methods and other imaging technologies and is a powerful instrument for studying congenital anomalies. [source] Diagnosis of Nonmelanoma Skin Cancer/Keratinocyte Carcinoma: A Review of Diagnostic Accuracy of Nonmelanoma Skin Cancer Diagnostic Tests and TechnologiesDERMATOLOGIC SURGERY, Issue 10 2007METTE MOGENSEN MD BACKGROUND Nonmelanoma skin cancer (NMSC) is the most prevalent cancer in the light-skinned population. Noninvasive treatment is increasingly used for NMSC patients with superficial lesions, making the development of noninvasive diagnostic technologies highly relevant. OBJECTIVE The scope of this review is to present data on the current state-of-the-art diagnostic methods for keratinocyte carcinoma: basal cell carcinoma, squamous cell carcinoma, and actinic keratosis. METHODS AND MATERIALS MEDLINE, BIOSIS, and EMBASE searches on NMSC and physical and clinical examination, biopsy, molecular marker, ultrasonography, Doppler, optical coherence tomography, dermoscopy, spectroscopy, fluorescence imaging, confocal microscopy, positron emission tomography, computed tomography, magnetic resonance imaging, terahertz imaging, electrical impedance and sensitivity, specificity, and diagnostic accuracy. RESULTS State-of-the-art diagnostic research has been limited in this field, but encouraging results from the reviewed diagnostic trials have suggested a high diagnostic accuracy for many of the technologies. Most of the studies, however, were pilot or small studies and the results would need to be validated in larger trials. CONCLUSIONS Some of these new imaging technologies have the capability of providing new, three-dimensional in vivo, in situ understanding of NMSC development over time. Some of the new technologies described here have the potential to make it from the bench to the clinic. [source] Echocardiographic Evaluation of Ventricular Function in MiceECHOCARDIOGRAPHY, Issue 1 2007Jeffrey N. Rottman M.D. Ventricular dysfunction remains a hallmark of most cardiac disease. The mouse has become an essential model system for cardiovascular biology, and echocardiography an established tool in the study of normal and genetically altered mice. This review describes the measurement of ventricular function, most often left ventricular function, by echocardiographic methods in mice. Technical limitations related to the small size and rapid heart rate in the mouse initially argued for the performance of echocardiography under anesthesia. More recently, higher frame rates and smaller probes operating at higher frequencies have facilitated imaging of conscious mice in some, but not all, experimental protocols and conditions. Ventricular function may be qualitatively and quantitatively evaluated under both conditions. Particular detail is provided for measurement under conscious conditions, and measurement under conscious and sedated or anesthestized conditions are contrasted. Normal values for echocardiographic indices for the common C57BL/6 strain are provided. Diastolic dysfunction is a critical pathophysiologic component of many disease states, and progress in the echocardiographic evaluation of diastolic function is discussed. Finally, echocardiography exists among several competing imaging technologies, and these alternatives are compared. [source] State of play: Clearing the thoracolumbar spine in blunt trauma victimsEMERGENCY MEDICINE AUSTRALASIA, Issue 5-6 2006Marten C Howes Abstract Introduction:, The present article reviews the clinical and imaging clearance of the thoracic and lumbar spines of blunt trauma victims and the evolution of these strategies with the use of new imaging technologies. Methods:, A comprehensive literature search was performed, and articles identified were critically appraised Results:, Twenty papers were identified, 12 directly comparing computed tomography screening with plain X-rays. Evidence-based protocols are presented. The evolution of imaging strategies in response to new technology is described. Conclusions:, Thoracolumbar spine screening is best done using reformatted images acquired when scanning the chest and abdomen of high-risk multi-trauma patients. If computed tomography is not clinically indicated for investigation of other injuries then plain films are the first line investigation. [source] Development of New Pyrrolocoumarin Derivatives with Satisfactory Fluorescent Properties and Notably Large Stokes ShiftsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 36 2008Lei Chen Abstract Small, organic, fluorescent molecules with large Stokes shifts and long emission wavelengths are ideal dyes for various modern fluorescent imaging technologies such as FRET. In this study, we designed and synthesized a number of new fluorescent molecules on the basic structures of two pyrrolocoumarin skeletons where Fischer's indole synthesis and the Suzuki coupling successfully served as the efficient molecular editing protocols. The examination of the fluorescent properties and further structural optimization of these compounds afforded three new pyrrolocoumarin dyes with notably large Stokes shifts and satisfactory fluorescent properties. Among these, 30 showed a large Stokes shift (113 nm) and intense fluorescence (, = 0.55, ,em = 523 nm), and thus showed great potential in biological imaging studies. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Nanoshells with Targeted Simultaneous Enhancement of Magnetic and Optical Imaging and Photothermal Therapeutic ResponseADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Rizia Bardhan Abstract Integrating multiple functionalities into individual nanoscale complexes is of tremendous importance in biomedicine, expanding the capabilities of nanoscale structures to perform multiple parallel tasks. Here, the ability to enhance two different imaging technologies simultaneously,fluorescence optical imaging and magnetic resonance imaging,with antibody targeting and photothermal therapeutic actuation is combined all within the same nanoshell-based complex. The nanocomplexes are constructed by coating a gold nanoshell with a silica epilayer doped with Fe3O4 and the fluorophore ICG, which results in a high T2 relaxivity (390,mM,1,s,1) and 45× fluorescence enhancement of ICG. Bioconjugate nanocomplexes target HER2+ cells and induce photothermal cell death upon near-IR illumination. [source] Dynamic regulation of T-cell costimulation through TCR,CD28 microclustersIMMUNOLOGICAL REVIEWS, Issue 1 2009Tadashi Yokosuka Summary:, T-cell activation requires contact between T cells and antigen-presenting cells (APCs) to bring T-cell receptors (TCRs) and major histocompatibility complex peptide (MHCp) together to the same complex. These complexes rearrange to form a concentric circular structure, the immunological synapse (IS). After the discovery of the IS, dynamic imaging technologies have revealed the details of the IS and provided important insights for T-cell activation. We have redefined a minimal unit of T-cell activation, the ,TCR microcluster', which recognizes MHCp, triggers an assembly of assorted molecules downstream of the TCR, and induces effective signaling from TCRs. The relationship between TCR signaling and costimulatory signaling was analyzed in terms of the TCR microcluster. CD28, the most valuable costimulatory receptor, forms TCR,CD28 microclusters in cooperation with TCRs, associates with protein kinase C ,, and effectively induces initial T-cell activation. After mature IS formation, CD28 microclusters accumulate at a particular subregion of the IS, where they continuously assemble with the kinases and not TCRs, and generate sustained T-cell signaling. We propose here a ,TCR,CD28 microcluster' model in which TCR and costimulatory microclusters are spatiotemporally formed at the IS and exhibit fine-tuning of T-cell responses by assembling with specific players downstream of the TCR and CD28. [source] Co-registered spectrally encoded confocal microscopy and optical frequency domain imaging systemJOURNAL OF MICROSCOPY, Issue 2 2010D.K. KANG Summary Spectrally encoded confocal microscopy and optical frequency domain imaging are two non-contact optical imaging technologies that provide images of tissue cellular and architectural morphology, which are both used for histopathological diagnosis. Although spectrally encoded confocal microscopy has better transverse resolution than optical frequency domain imaging, optical frequency domain imaging can penetrate deeper into tissues, which potentially enables the visualization of different morphologic features. We have developed a co-registered spectrally encoded confocal microscopy and optical frequency domain imaging system and have obtained preliminary images from human oesophageal biopsy samples to compare the capabilities of these imaging techniques for diagnosing oesophageal pathology. [source] Digital imaging in transmission electron microscopyJOURNAL OF MICROSCOPY, Issue 1 2000G. Y. Fan The digital revolution currently under way, as evidenced by the rapid development of the Internet and the world-wide-web technologies, is undoubtedly impacting the field of transmission electron microscopy (TEM). Digital imaging systems based on charge-coupled device (CCD) technologies, with pixel array size up to 2 k × 2 k at the present and increasing, are available for TEM applications and offer many attractions. Is it time to phase out film cameras on TEMs and close the darkrooms for good? This paper reviews digital imaging technologies for TEM at different voltages, and contrasts the performance of digital imaging systems with that of TEM film. The performance characteristics of CCD-based digital imaging systems, as well as methods for assessing them, are discussed. Other approaches to digital imaging are also briefly reviewed. [source] Timing of potential and metabolic brain energyJOURNAL OF NEUROCHEMISTRY, Issue 5 2007Jakob Korf Abstract The temporal relationship between cerebral electro-physiological activities, higher brain functions and brain energy metabolism is reviewed. The duration of action potentials and transmission through glutamate and GABA are most often less than 5 ms. Subjects may perform complex psycho-physiological tasks within 50 to 200 ms, and perception of conscious experience requires 0.5 to 2 s. Activation of cerebral oxygen consumption starts after at least 100 ms and increases of local blood flow become maximal after about 1 s. Current imaging technologies are unable to detect rapid physiological brain functions. We introduce the concepts of potential and metabolic brain energy to distinguish trans-membrane gradients of ions or neurotransmitters and the capacity to generate energy from intra- or extra-cerebral substrates, respectively. Higher brain functions, such as memory retrieval, speaking, consciousness and self-consciousness are so fast that their execution depends primarily on fast neurotransmission (in the millisecond range) and action-potentials. In other words: brain functioning requires primarily maximal potential energy. Metabolic brain energy is necessary to restore and maintain the potential energy. [source] Stem cell-mediated accelerated bone healing observed with in vivo molecular and small animal imaging technologies in a model of skeletal injuryJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2009Sheen-Woo Lee Abstract Adult stem cells are promising therapeutic reagents for skeletal regeneration. We hope to validate by molecular imaging technologies the in vivo life cycle of adipose-derived multipotent cells (ADMCs) in an animal model of skeletal injury. Primary ADMCs were lentivirally transfected with a fusion reporter gene and injected intravenously into mice with bone injury or sham operation. Bioluminescence imaging (BLI), [18F]FHBG (9-(fluoro-hydroxy-methyl-butyl-guanine)-micro-PET, [18F]Fluoride ion micro-PET and micro-CT were performed to monitor stem cells and their effect. Bioluminescence microscopy and immunohistochemistry were done for histological confirmation. BLI showed ADMC's traffic from the lungs then to the injury site. BLI microscopy and immunohistochemistry confirmed the ADMCs in the bone defect. Micro-CT measurements showed increased bone healing in the cell-injected group compared to the noninjected group at postoperative day 7 (p,<,0.05). Systemically administered ADMC's traffic to the site of skeletal injury and facilitate bone healing, as demonstrated by molecular and small animal imaging. Molecular imaging technologies can validate the usage of adult adipose tissue-derived multipotent cells to promote fracture healing. Imaging can in the future help establish therapeutic strategies including dosage and administration route. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:295,302, 2009 [source] Learning to Read in the Digital AgeMIND, BRAIN, AND EDUCATION, Issue 2 2009David Rose ABSTRACT ABSTRACT,The digital age offers transformative opportunities for individualization of learning. First, modern imaging technologies have changed our understanding of learning and the sources and ranges of its diversity. Second, digital technologies make it possible to design learning environments that are responsive to individual differences. We draw on CAST's research and development on universal design for learning to suggest the potential of digital reading environments that are designed to support learning and engagement by addressing the diversity in learners' representation, strategic and affective networks. Optimal customization depends on continued advances in the digital tools of the neurosciences and the design and enactment of digital learning environments. [source] Evaluating anatomical research in surgery: a prospective comparison of cadaveric and living anatomical studies of the abdominal wallANZ JOURNAL OF SURGERY, Issue 12 2009Warren M. Rozen Abstract Background:, Cadaveric research has widely influenced our understanding of clinical anatomy. However, while many soft-tissue structures remain quiescent after death, other tissues, such as viscera, undergo structural and functional changes that may influence their use in predicting living anatomy. In particular, our understanding of vascular anatomy has been based upon cadaveric studies, in which vascular tone and flow do not match the living situation. Methods:, An angiographic analysis of the abdominal wall vasculature was performed using plain film and computed tomography angiography in 60 cadaveric hemi-abdominal walls (from 31 cadavers) and 140 living hemi-abdominal walls (in 70 patients). The deep inferior epigastric artery (DIEA) and all of its perforating branches larger than 0.5 mm were analysed for number, calibre and location. Results:, Both large, named vessels and small calibre vessels show marked differences between living anatomy and cadaveric specimens. The DIEA was of larger diameter (4.2 mm versus 3.1 mm, P < 0.01) and had more detectable branches in the cadaveric specimens. Perforators were of greater calibre (diameter 1.5 mm versus 0.8 mm, P < 0.01) and were more plentiful (16 versus 6, P < 0.01) in cadaveric specimens. However, the location of individual vessels was similar. Conclusions:, Cadaveric anatomy displays marked differences to in vivo anatomy, with the absence of living vascular dynamics affecting vessel diameters in cadaveric specimens. Blood vessels are of greater measurable calibre in cadaveric specimens than in the living. Consequently, cadaveric anatomy should be interpreted with consideration of post-mortem changes, while living anatomical studies, particularly with the use of imaging technologies, should be embraced in anatomical research. [source] Modifying techniques in deep inferior epigastric artery perforator flap harvest with the use of preoperative imagingANZ JOURNAL OF SURGERY, Issue 9 2009Warren M. Rozen Abstract New techniques in the harvest of deep inferior epigastric artery perforator (DIEP) flaps have become introduced as a result of modern imaging technologies that can allow virtual surgery to be achieved preoperatively. With computed tomographic angiography, individual anatomy can be appreciated in detail to a level not previously appreciated. These imaging techniques can be successfully used to guide DIEP flap surgery. ,Optimal' perforators can be selected based on size, location, intramuscular and subcutaneous course, and their association with motor nerves. Flap design can be safely achieved based on the cutaneous distribution of perforators. Abdominal wall closure can be improved based on the abdominal contour seen with imaging. Preoperative planning can aid patient selection, plan all aspects of the operative technique, reduce operating time and improve operative outcomes. [source] 2452: Patients in the DARC: drops revealing retinal ganglion cells in vivoACTA OPHTHALMOLOGICA, Issue 2010MF CORDEIRO Purpose To provide a review of current & future DARC imaging technologies and their application to neuroprotection Methods Currently, lowering IOP remains the only clinical therapy available in the treatment of glaucoma, despite the evidence that vision loss can continue in the presence of "significant" IOP reduction. Neuroprotection has been increasingly recognized as an important alternative treatment approach, but its emergence has also highlighted the need for both better defined end-points in clinical glaucoma research, as well as earlier and better detection and measures of progression. This could have been a factor in the recent memantine trial. A recent FDA/NEI meeting on end-points in glaucoma emphasized the need for new measurements. As the RGC is the primary injured neuron in this disease, it would seem logical that any modality that could directly measure RGC dysfunction and disease would be ideal. Perhaps the greatest changes that we have encountered recently are in the field of imaging technologies, which have only relatively recently been applied to the eye. Results Advances in this area have allowed unprecedented in vivo access to the retinal layers, using many different properties of light to differentiate cellular structures. DARC is a technology shortly to enter clinical trials which allows the visualization of "sick" RGCs. Conclusion Over the next few years, developments in therapy & diagnostic using DARC should offer great potential in glaucoma and other neurodegenerative conditions. Commercial interest [source] New perspectives in retinal imaging: fundus autofluorescence and age-related macular degenerationACTA OPHTHALMOLOGICA, Issue 2007F HOLZ Fundus Autofluorescence (FAF) imaging using confocal scanning laser ophthalmoscopy is a non-invasive method to to accurately record the topographic distribution of RPE lipofuscin in the human eye in vivo. Excessive lipofuscin accumkulation in the RPE is a common downstream pathogenetic pathway in various complex and monogenetic retinal diseases. Toxic compounds and molecular mechanisms of interference with normal cellular functions have been identified including the dominant fluorophore A2-E. Alterations in fundus autofluorescence (FAF) appearance in eyes with early and late age-related macular degeneration (AMD) can be striking. FAF patterns and distribution do not necessarily correlate with the features of interest in color or angiographic images of eyes with early or late AMD. In the prospective, multicenter FAM study distinct patterns of abnormal FAF were identified and classified in the junctional zone of geographic atrophy (GA). Areas of increased FAF outside GA were associated with variable degrees of loss of retinal sensitivity when tested with microperimetry which suggests a functional correlate of lipofuscin accumulation. Increased FAF preceded the development and enlargement of outer retinal atrophy associated with spread of absolute scotoma in eyes with AMD. Longitudinal examinations showed that the abnormal phenotypic FAF patterns serve as novel prognostic determinants which allows to distinguish fast vs. slow progressors. These findings are relevant and now used to design and carry out interventional trials with agents aimed at slowing down spread of atrophy, e.g. using visual cycle modulators to influence lipofuscinogenesis. Hereby FAF imaging also serves as a mean to accurately delineate and measure areas of GA over time in an automated fashion. A phenotype-genotype correlation was identified for a distinct FAF phenotype subset which was found to represent late-onset Stargardt macular dystrophy mimicking late-stage atrophic AMD. New imaging technologies were recently applied including simultaneous recordings of FAF images and high-resolution, spectral-domain optical coherence tomography (OCT) which allows to identify morphological correlates of abnormal FAF signals in optical biopsies. [source] The influence of age, sex, race, refractive error and optic disc parameters on the sensitivity and specificity of scanning laser polarimetryACTA OPHTHALMOLOGICA, Issue 4 2004Vital P. Costa Abstract. Purpose:,To evaluate the influence of age, sex, race, refractive error and optic disc topography on the sensitivity and specificity of scanning laser polarimetry (SLP) in the diagnosis of glaucoma. Methods:,A total of 88 normal individuals and 95 glaucoma patients were included in this study. Glaucoma was defined on the basis of both optic nerve damage and visual field defects. Scanning laser polarimetry, optic disc topography, automated perimetry and refractometry were performed in all subjects. The sensitivity and specificity of SLP were assessed applying a previously calculated cut-off to a previously described linear discriminant function (LDF). Results:,The sensitivity and specificity of SLP in the study population were 82% and 83%, respectively. Sensitivity and specificity were not affected by age, sex, race, average disc diameter or disc area. The sensitivity of SLP tended to be higher in myopes (93%) than in emmetropes (80%) and hyperopes (71%) (p = 0.08). Sensitivities were higher in individuals with cup areas > 0.96 mm2 (89%), rim areas , 1.36 mm2 (92%), and cup area/disc area ratios > 0.45 (89%) (p < 0.05). Stepwise logistic regression analysis indicated that the presence of a cup area > 0.96 mm2 and a rim area < 1.36 mm2 significantly increased the sensitivity of the LDF, whereas a cup area/disc area ratio , 0.45 significantly increased the specificity of the LDF. Conclusion:,The sensitivity and specificity of SLP may be influenced by refractive error and optic disc parameters that are affected by glaucomatous damage (cup area, rim area and cup area/disc area ratio). These parameters must be considered in studies evaluating the sensitivity and specificity of optic nerve/retinal nerve fibre layer imaging technologies. [source] Reviewing the vascular supply of the anterior abdominal wall: Redefining anatomy for increasingly refined surgeryCLINICAL ANATOMY, Issue 2 2008W.M. Rozen Abstract The abdominal wall integument is becoming the standard donor tissue for postmastectomy breast reconstruction, with its vascular supply of key importance to the reconstructive surgeon. Refinements in tissue transfer, from pedicled to free flaps and musculocutaneous to perforator flaps, have required increasing understanding of finer levels of this vascular anatomy. The widespread utilization of the deep inferior epigastric artery (DIEA) perforator flap, particularly for breast reconstruction, has rekindled clinical interest in further levels of anatomical detail, in particular the location and course of the musculocutaneous perforators of the DIEA. Advances in operative techniques, and anatomical and imaging technologies, have facilitated an increase in this understanding. The current review comprises an appraisal of both the anatomical and clinical literature, with a view to highlighting the key anatomical features of the abdominal wall vasculature as related to reconstructive flaps. Clin. Anat. 21:89,98, 2008. © 2008 Wiley-Liss, Inc. [source] NRC 3D imaging technology for museum and heritage applicationsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3 2003J. Taylor Abstract The National Research Council of Canada (NRC) has developed and patented three high-resolution 3D imaging systems and processing algorithms which have been applied to a wide range of museum and heritage recording applications. The systems have been designed for different imaging applications and, in collaboration with a number of national and international museums and cultural agencies, have been used to scan a wide variety of objects and sites. The objective of this paper is to present a summary of the 3D technology and examples of its heritage applications. Copyright © 2003 John Wiley & Sons, Ltd. [source] REVIEW: Stress, alcohol and drug interaction: an update of human researchADDICTION BIOLOGY, Issue 1 2009Magdalena Uhart ABSTRACT A challenging question that continues unanswered in the field of addiction is why some individuals are more vulnerable to substance use disorders than others. Numerous risk factors for alcohol and other drugs of abuse, including exposure to various forms of stress, have been identified in clinical studies. However, the neurobiological mechanisms that underlie this relationship remain unclear. Critical neurotransmitters, hormones and neurobiological sites have been recognized, which may provide the substrates that convey individual differences in vulnerability to addiction. With the advent of more sophisticated measures of brain function in humans, such as functional imaging technology, the mechanisms and neural pathways involved in the interactions between drugs of abuse, the mesocorticolimbic dopamine system and stress systems are beginning to be characterized. This review provides a neuroadaptive perspective regarding the role of the hormonal and brain stress systems in drug addiction with a focus on the changes that occur during the transition from occasional drug use to drug dependence. We also review factors that contribute to different levels of hormonal/brain stress activation, which has implications for understanding individual vulnerability to drug dependence. Ultimately, these efforts may improve our chances of designing treatment strategies that target addiction at the core of the disorder. [source] Clinical value of optical coherence tomography in laryngologyHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 12 2008Marcel Kraft MD Abstract Background. Optical coherence tomography (OCT) is a new, noninvasive imaging technology for the evaluation of superficial lesions. The objective of this study is to evaluate microlaryngoscopy in combination with OCT compared with microlaryngoscopy alone (ie, without OCT) in supplying a specific diagnosis, predicting invasive tumor growth and epithelial dysplasia in the larynx. Methods. This was a prospective study including 217 laryngeal lesions in a total of 193 patients undergoing surgery. Intraoperative suspicion diagnosis gained by microlaryngoscopy with and without OCT was compared with conventional histopathology after excisional biopsy. Results. Microlaryngoscopy with OCT supplied a specific diagnosis in 89% of cases, but in only 80% of cases with microlaryngoscopy alone. In particular, our results in malignant and benign pathologies were correct in 93% each, and the exact grade of dysplasia could be predicted in 71% of precancerous lesions. Microlaryngoscopy with OCT presented a higher sensitivity than microlaryngoscopy alone in predicting invasive tumor growth (93% vs 87%) and epithelial dysplasia (78% vs 66%), but the specificity and accuracy were comparable in both methods. Conclusions. OCT is a simple, rapid, and reliable aid in the diagnostic investigation and intraoperative monitoring of laryngeal disease. © 2008 Wiley Periodicals, Inc. Head Neck, 2008 [source] The human hippocampus at 7 T,In vivo MRIHIPPOCAMPUS, Issue 1 2009Jens M. Theysohn Abstract The human hippocampus plays a central role in various neuropsychiatric disorders, such as temporal lobe epilepsy (TLE), Alzheimer's dementia, mild cognitive impairment, and schizophrenia. Its volume, morphology, inner structure, and function are of scientific and clinical interest. Magnetic resonance (MR) imaging is a widely employed tool in neuroradiological workup regarding changes in brain anatomy, (sub-) volumes, and cerebral function including the hippocampus. Gain in intrinsic MR signal provided by higher field strength scanners and concomitant improvements in spatial resolution seem highly valuable. An examination protocol permitting complete, high-resolution imaging of the human hippocampus at 7 T was implemented. Coronal proton density, T2, T2*, and fluid-attenuated inversion recovery contrasts were acquired as well as an isotropic 3D magnetization-prepared rapid acquisition gradient-echo (500 ,m isotropic voxel dimension, noninterpolated). Observance of energy deposition restrictions within acceptable scan times remained challenging in the acquisition of thin, spin-echo-based sections. At the higher resolution enabled by 7 T, demarcation of the hippocampus and some internal features including gray/white matter differentiation and depiction of the hippocampal mantle becomes much more viable when compared with 1.5 T; thus, in the future, this imaging technology might help in the diagnosis of subtle hippocampal changes. © 2008 Wiley-Liss, Inc. [source] Hilar cholangiocarcinoma: diagnosis and stagingHPB, Issue 4 2005William Jarnagin Cancer arising from the proximal biliary tree, or hilar cholangiocarcinoma, remains a difficult clinical problem. Significant experience with these uncommon tumors has been limited to a small number of centers, which has greatly hindered progress. Complete resection of hilar cholangiocarcinoma is the most effective and only potentially curative therapy, and it now clear that concomitant hepatic resection is required in most cases. Simply stated, long-term survival is generally possible only with an en bloc resection of the liver with the extrahepatic biliary apparatus, leaving behind a well perfused liver remnant with adequate biliary-enteric drainage. Preoperative imaging studies should aim to assess this possibility and must evaluate a number of tumor-related factors that influence resectability. Advances in imaging technology have improved patient selection, but a large proportion of patients are found to have unresectable disease only at the time of exploration. Staging laparoscopy and 13fluoro-deoxyglucose positron emission tomography (FDG-PET) may help to identify some patients with advanced disease; however, local tumor extent, an equally critical determinant of resectability, may be underestimated on preoperative studies. This paper reviews issues pertaining to diagnosis and preoperative evaluation of patients with hilar biliary obstruction. Knowledge of the imaging features of hilar tumors, particularly as they pertain to resectability, is of obvious importance for clinicians managing these patients. [source] Diagnostic and therapeutic use of radioisotopes for bony disease in prostate cancer: Current practiceINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2007Nathan Lawrentschuk Abstract: Nuclear medicine techniques continue to be important non-invasive imaging tools assisting the diagnosis, monitoring and , in some cases , treatment of prostate cancer. Bone scintigraphy was the premier modality to have an extensive role in the staging of prostate cancer and has remained an integral tool for over three decades in the assessment of newly diagnosed disease or in follow-up staging. Therapeutic treatment and palliation of disseminated disease, particularly in the skeleton, has also been successful with several radioisotopes including strontium-89 chloride. Despite advances in nuclear medicine techniques and molecular imaging technology such as positron emission tomography and radioimmunoscintigraphy, bone scintigraphy still remains the gold standard in the assessment of osseous metastatic disease in prostate cancer. Thus, it is important to continually review the modalities that have remained important over time and not just to focus on newer technologies. This article summarizes the current diagnostic and therapeutic use of radioisotopes for bony disease in prostate cancer with particular reference to radionuclide bone scintigraphy and positron emission tomography. [source] Expression of synapsin and co-localization with serotonin and RFamide-like immunoreactivity in the nervous system of the chordoid larva of Symbion pandora (Cycliophora)INVERTEBRATE BIOLOGY, Issue 1 2010Ricardo Cardoso Neves Abstract. Cycliophora is one of the most recently described metazoan phyla and hitherto includes only two species: Symbion pandora and Symbion americanus. With a very complex life cycle, cycliophorans are regarded as an enigmatic group with an uncertain phylogenetic position, although they are commonly considered lophotrochozoan protostomes. In order to extend the database concerning the distribution of immunoreactive substances in the free-swimming chordoid larva of S. pandora, we investigated synapsin immunoreactivity using fluorescence-coupled antibodies in combination with confocal laserscanning microscopy. Moreover, we analyzed the co-localization patterns of synapsin, serotonin, and RFamide-like immunoreactivity in the chordoid larva by 3D imaging technology based on the confocal microscopy image stacks. Synapsin is expressed in large parts of the bilobed anterior cerebral ganglion including anterior and dorsal projections. Two pairs of ventral neurites run longitudinally into the larval body of which the inner pair shows only weak, scattered synapsin immunoreactivity. In addition, a lateral synapsin immunoreactive projection emerges posteriorly from each ventral longitudinal axon. Double immunostaining shows co-localization of synapsin and serotonin in the cerebral ganglion, the outer and the inner ventral neurites, and the anterior projections. Synapsin and RFamide-like immunoreactivity co-occur in the cerebral ganglion, the outer ventral neurites, and the dorsal projections. Accordingly, the cerebral ganglion and the outer ventral neurites are the only neural structures that co-express the two neurotransmitters and synapsin. The overall neuroanatomical condition of the cycliophoran chordoid larva resembles much more the situation of adult rather than larval life cycle stages of a number of spiralian taxa. [source] Imaging engineered tissues using structural and functional optical coherence tomographyJOURNAL OF BIOPHOTONICS, Issue 11 2009Xing Liang Abstract As the field of tissue engineering evolves, there will be an increasingly important need to visualize and track the complex dynamic changes that occur within three-dimensional constructs. Optical coherence tomography (OCT), as an emerging imaging technology applied to biological materials, offers a number of significant advantages to visualize these changes. Structural OCT has been used to investigate the longitudinal development of engineered tissues and cell dynamics such as migration, proliferation, detachment, and cell-material interactions. Optical techniques that image functional parameters or integrate multiple imaging modalities to provide complementary contrast mechanisms have been developed, such as the integration of optical coherence microscopy with multiphoton microscopy to image structural and functional information from cells in engineered tissue, optical coherence elastography to generate images or maps of strain to reflect the spatially-dependent biomechanical properties, and spectroscopic OCT to differentiate different cell types. From these results, OCT demonstrates great promise for imaging and visualizing engineered tissues, and the complex cellular dynamics that directly affect their practical and clinical use. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||||||||||||||||||||||||||||||||