Michael J. Knight, B. Wood, Elizabeth Couthard, R. Kauppinen
BACKGROUND: The use of T2 relaxation contrast, as measured by MRI, is particularly commonplace in non-invasive assessment of the brain. However, the mechanisms and uses of T2 relaxation in the brain are still not fully understood. The hypothesis that T2 relaxation may show anisotropy in the human brain was studied at 3 T. T2 anisotropy refers to the variation of T2 in ordered structures with respect to the direction of the applied magnetic field. METHODS: Using a 3 T clinical MRI scanner, we made quantitative multi-contrast spin-echo T2 and diffusion tensor imaging (DTI) measurements in healthy volunteers, repeating the measurements with the subject’s head oriented differently relative to the applied field, for the measurement of possible spin-echo T2 anisotropy. RESULTS: We report T2 relaxation anisotropy measurements and present a means for visualising it according to the principal orientation of ordered structures in the brain parenchyma. We introduce a parameter for the model-free description of T2 anisotropy, namely the T2 “fractional anisotropy”, similar to that used to describe anisotropy of translational diffusion. This parameterisation enables the overall level of anisotropy in T2 across a chosen region or tissue to be calculated. Anisotropic T2 relaxation was observed in both gray and white matter, though to a greater extent in the latter, with a strong relationship with the anisotropy of translational diffusion. This is evidenced by making repeat measurements with the subject’s head tilted to different angles relative to the applied magnetic field, by which means we observed the T2 at the same anatomical site to change. CONCLUSIONS: Relaxation anisotropy has a significant effect on T2 in the brain parenchyma. It has the potential to offer non-invasive access to tissue microstructure not available by other imaging modalities, and may be sensitive to pathology or noxious factors not detected by other means.
{"title":"Anisotropy of spin-echo T2 relaxation by magnetic resonance imaging in the human brain in vivo","authors":"Michael J. Knight, B. Wood, Elizabeth Couthard, R. Kauppinen","doi":"10.3233/BSI-150114","DOIUrl":"https://doi.org/10.3233/BSI-150114","url":null,"abstract":"BACKGROUND: The use of T2 relaxation contrast, as measured by MRI, is particularly commonplace in non-invasive assessment of the brain. However, the mechanisms and uses of T2 relaxation in the brain are still not fully understood. The hypothesis that T2 relaxation may show anisotropy in the human brain was studied at 3 T. T2 anisotropy refers to the variation of T2 in ordered structures with respect to the direction of the applied magnetic field. METHODS: Using a 3 T clinical MRI scanner, we made quantitative multi-contrast spin-echo T2 and diffusion tensor imaging (DTI) measurements in healthy volunteers, repeating the measurements with the subject’s head oriented differently relative to the applied field, for the measurement of possible spin-echo T2 anisotropy. RESULTS: We report T2 relaxation anisotropy measurements and present a means for visualising it according to the principal orientation of ordered structures in the brain parenchyma. We introduce a parameter for the model-free description of T2 anisotropy, namely the T2 “fractional anisotropy”, similar to that used to describe anisotropy of translational diffusion. This parameterisation enables the overall level of anisotropy in T2 across a chosen region or tissue to be calculated. Anisotropic T2 relaxation was observed in both gray and white matter, though to a greater extent in the latter, with a strong relationship with the anisotropy of translational diffusion. This is evidenced by making repeat measurements with the subject’s head tilted to different angles relative to the applied magnetic field, by which means we observed the T2 at the same anatomical site to change. CONCLUSIONS: Relaxation anisotropy has a significant effect on T2 in the brain parenchyma. It has the potential to offer non-invasive access to tissue microstructure not available by other imaging modalities, and may be sensitive to pathology or noxious factors not detected by other means.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"299-310"},"PeriodicalIF":0.0,"publicationDate":"2015-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-150114","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69856091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laurence D. Barron (Fig. 1) was born in Southampton (United Kingdom) in 1944. He studied Chemistry at the Northern Polytechnic and graduated with a first class honours degree from London University (internal) in 1965. He went on to study for his doctoral degree at Lincoln College (Oxford University) under the supervision of Prof. Peter W. Atkins. At Oxford, he discovered a new fundamental light scattering mechanism from chiral molecules from which he predicted the new phenomena of Rayleigh and Raman optical activity (ROA). After completion of his PhD in 1969, Laurence moved to Cambridge University to work with David Buckingham (Fig. 2) where they developed the definitive theory of ROA in 1971 [4] and utilised this phenomenon to obtain vibrational optical activity spectra of chiral molecules through the use of circularly polarised Raman spectroscopy [3]. Lau-
劳伦斯·d·巴伦(图1)1944年出生于英国南安普敦。他在北方理工学院学习化学，并于1965年以一等荣誉学位毕业于伦敦大学(内部)。他继续在牛津大学林肯学院攻读博士学位，师从Peter W. Atkins教授。在牛津大学，他从手性分子中发现了一种新的基本光散射机制，并据此预测了瑞利和拉曼光学活性(ROA)的新现象。1969年完成博士学位后，劳伦斯搬到剑桥大学与大卫·白金汉(图2)一起工作，在那里他们于1971年发展了ROA的确定理论，并利用这一现象通过使用圆极化拉曼光谱获得了手性分子的振动光学活性谱。刘-
{"title":"Laurence Barron: The founding father of Raman optical activity.","authors":"P. Haris","doi":"10.3233/BSI-150119","DOIUrl":"https://doi.org/10.3233/BSI-150119","url":null,"abstract":"Laurence D. Barron (Fig. 1) was born in Southampton (United Kingdom) in 1944. He studied Chemistry at the Northern Polytechnic and graduated with a first class honours degree from London University (internal) in 1965. He went on to study for his doctoral degree at Lincoln College (Oxford University) under the supervision of Prof. Peter W. Atkins. At Oxford, he discovered a new fundamental light scattering mechanism from chiral molecules from which he predicted the new phenomena of Rayleigh and Raman optical activity (ROA). After completion of his PhD in 1969, Laurence moved to Cambridge University to work with David Buckingham (Fig. 2) where they developed the definitive theory of ROA in 1971 [4] and utilised this phenomenon to obtain vibrational optical activity spectra of chiral molecules through the use of circularly polarised Raman spectroscopy [3]. Lau-","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"219-222"},"PeriodicalIF":0.0,"publicationDate":"2015-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-150119","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69856404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Beata Mickiewicz, K. Huebner, Johnny K. Chau, N. Shrive, C. Frank, H. Vogel, D. Hart
Background: Surgical models of bone injury-induced joint damage provide relevant insights into the biological pathways involved in the response to injury and development of subsequent degenerative joint conditions. Objective: To determine metabolic changes acutely following a bone injury to the rabbit knee in order to reveal key metabolites potentially associated with the chronic phase post-injury leading to post-traumatic osteoarthritis. Methods: Nine skeletally mature rabbits underwent surgery to create a repeatable, isolated intra-articular bone injury with intraarticular bleeding, without destabilizing the knee. Plasma samples were collected pre-operatively (baseline) and at 3 weeks post-injury. The samples were analyzed using nuclear magnetic resonance spectroscopy-based metabolic profiling approach and multivariate statistical analysis. Results: Metabolic profiling found clear separation between pre-surgical and post-injury rabbits. The predictive ability of the statistical model reached 75%. The levels of twelve metabolites (adenine, choline, glutamine, glycine, pyroglutamate, ornithine, 1-methylhistidine, creatinine, acetate, glucose, taurine and glutamate) significantly changed in plasma samples collected from the rabbits 3 weeks post-injury compared to their baseline levels. Conclusions: Our study indicates that metabolomics may have important applications in the detection of early systemic changes following a localized joint injury, possibly enabling early intervention and preventing progression to more serious joint degeneration.
{"title":"Metabolic profile of plasma before and after induction of an isolated intra-articular bone injury in the rabbit knee: Potential to characterize the onset of osteoarthritis?","authors":"Beata Mickiewicz, K. Huebner, Johnny K. Chau, N. Shrive, C. Frank, H. Vogel, D. Hart","doi":"10.3233/BSI-150122","DOIUrl":"https://doi.org/10.3233/BSI-150122","url":null,"abstract":"Background: Surgical models of bone injury-induced joint damage provide relevant insights into the biological pathways involved in the response to injury and development of subsequent degenerative joint conditions. Objective: To determine metabolic changes acutely following a bone injury to the rabbit knee in order to reveal key metabolites potentially associated with the chronic phase post-injury leading to post-traumatic osteoarthritis. Methods: Nine skeletally mature rabbits underwent surgery to create a repeatable, isolated intra-articular bone injury with intraarticular bleeding, without destabilizing the knee. Plasma samples were collected pre-operatively (baseline) and at 3 weeks post-injury. The samples were analyzed using nuclear magnetic resonance spectroscopy-based metabolic profiling approach and multivariate statistical analysis. Results: Metabolic profiling found clear separation between pre-surgical and post-injury rabbits. The predictive ability of the statistical model reached 75%. The levels of twelve metabolites (adenine, choline, glutamine, glycine, pyroglutamate, ornithine, 1-methylhistidine, creatinine, acetate, glucose, taurine and glutamate) significantly changed in plasma samples collected from the rabbits 3 weeks post-injury compared to their baseline levels. Conclusions: Our study indicates that metabolomics may have important applications in the detection of early systemic changes following a localized joint injury, possibly enabling early intervention and preventing progression to more serious joint degeneration.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"359-371"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-150122","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69856021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Determination of ulcer in the digestive tract using image analysis in wireless capsule endoscopy","authors":"Jin Park, G. Yoon","doi":"10.3233/BSI-150124","DOIUrl":"https://doi.org/10.3233/BSI-150124","url":null,"abstract":"","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"33 1","pages":"373-390"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-150124","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69856113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Beleites, O. Guntinas-Lichius, G. Ernst, J. Popp, C. Krafft
The advent of FTIR microscopic spectrometers with focal plane array detectors enabled rapid image acquisition with diffraction limited lateral resolution. The field of view depends on the magnification and the detector size. FTIR images of large samples can be collected in the so called mosaic mode by stitching individual images together. If the mosaic is composed of hundreds of images, the total acquisition time and the data size will increase considerably. One computational and two optical options are compared to reduce both acquisition time and data size. First, the 2× field expansion optic increases the measured sample area fourfold. Second, using a 4× objective instead of the standard 15× objective increases the area covered by a single image by a factor of 11. Third, pixel binning averages neighboring pixels at the expense of lateral resolution. All options are demonstrated in a case study of a thin section of laryngeal carcinoma encompassing normal tissue, inflammation, connective tissue, dysplasia, carcinoma and blood. Data analysis is described using the toolbox hyperSpec operating under the R environment and complemented by parallel computing functions. A classification model that was trained with low magnification data in the range from 1200 to 1800 cm−1 gave similar results for higher magnification data. Restrictions occurred for microscopic features smaller than the detector pixel size and for biomarkers below 1200 cm−1 due to signal attenuation of the 4× objective lenses. FTIR imaging mosaic strategies of other groups and the emerging use of quantum cascade lasers for IR imaging are discussed.
{"title":"FTIR microscopic imaging of carcinoma tissue section with 4× and 15× objectives: Practical considerations","authors":"C. Beleites, O. Guntinas-Lichius, G. Ernst, J. Popp, C. Krafft","doi":"10.3233/BSI-140101","DOIUrl":"https://doi.org/10.3233/BSI-140101","url":null,"abstract":"The advent of FTIR microscopic spectrometers with focal plane array detectors enabled rapid image acquisition with diffraction limited lateral resolution. The field of view depends on the magnification and the detector size. FTIR images of large samples can be collected in the so called mosaic mode by stitching individual images together. If the mosaic is composed of hundreds of images, the total acquisition time and the data size will increase considerably. One computational and two optical options are compared to reduce both acquisition time and data size. First, the 2× field expansion optic increases the measured sample area fourfold. Second, using a 4× objective instead of the standard 15× objective increases the area covered by a single image by a factor of 11. Third, pixel binning averages neighboring pixels at the expense of lateral resolution. All options are demonstrated in a case study of a thin section of laryngeal carcinoma encompassing normal tissue, inflammation, connective tissue, dysplasia, carcinoma and blood. Data analysis is described using the toolbox hyperSpec operating under the R environment and complemented by parallel computing functions. A classification model that was trained with low magnification data in the range from 1200 to 1800 cm−1 gave similar results for higher magnification data. Restrictions occurred for microscopic features smaller than the detector pixel size and for biomarkers below 1200 cm−1 due to signal attenuation of the 4× objective lenses. FTIR imaging mosaic strategies of other groups and the emerging use of quantum cascade lasers for IR imaging are discussed.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"57-66"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-140101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69855843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Tripon, C. Muntean, L. Buimaga-Iarinca, A. Calborean
{"title":"DFT investigation of the vibrational properties of AT base pairs in the presence of Ca2+ and Mn2+ ions","authors":"C. Tripon, C. Muntean, L. Buimaga-Iarinca, A. Calborean","doi":"10.3233/BSI-150110","DOIUrl":"https://doi.org/10.3233/BSI-150110","url":null,"abstract":"","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"189-196"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-150110","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69856322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Johan Härmark, M. Larsson, A. Razuvajev, P. Koeck, G. Paradossi, L. Brodin, K. Caidahl, H. Hebert, A. Bjällmark
BACKGROUND: A novel polymer-shelled contrast agent (CA) with multimodal imaging and target specific potential was developed recently and tested for its acoustical properties using different in-vitr ...
{"title":"Investigation of the elimination process of a multimodal polymer-shelled contrast agent in rats using ultrasound and transmission electron microscopy","authors":"Johan Härmark, M. Larsson, A. Razuvajev, P. Koeck, G. Paradossi, L. Brodin, K. Caidahl, H. Hebert, A. Bjällmark","doi":"10.3233/BSI-140099","DOIUrl":"https://doi.org/10.3233/BSI-140099","url":null,"abstract":"BACKGROUND: A novel polymer-shelled contrast agent (CA) with multimodal imaging and target specific potential was developed recently and tested for its acoustical properties using different in-vitr ...","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"81-93"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-140099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69855507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biomedical optical imaging and optical spectroscopy are rapidly emerging as strong contenders for non-invasive optical biopsy. In biomedical imaging, Optical Coherence Tomography (OCT) is an established imaging modality for non- contact depth-resolved three-dimensional imaging with micrometer scale resolution. OCT provides label-free micro-structural morphological information of the tissue. Raman spectroscopy is a complementary tool for obtaining molecular-specific infor- mation for diagnosis. This article provides a brief overview of the underlying principles of OCT and Raman spectroscopy, their instrumentation with representative latest developments in cancer diagnosis.
{"title":"Perspectives of optical coherence tomography imaging and Raman spectroscopy in cancer diagnosis","authors":"K. Divakar Rao, N.K. Sahoo, C. Murali Krishna","doi":"10.3233/BSI-140097","DOIUrl":"https://doi.org/10.3233/BSI-140097","url":null,"abstract":"Biomedical optical imaging and optical spectroscopy are rapidly emerging as strong contenders for non-invasive optical biopsy. In biomedical imaging, Optical Coherence Tomography (OCT) is an established imaging modality for non- contact depth-resolved three-dimensional imaging with micrometer scale resolution. OCT provides label-free micro-structural morphological information of the tissue. Raman spectroscopy is a complementary tool for obtaining molecular-specific infor- mation for diagnosis. This article provides a brief overview of the underlying principles of OCT and Raman spectroscopy, their instrumentation with representative latest developments in cancer diagnosis.","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"35-55"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-140097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69855483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Isao Noda - Father of two-dimensional correlation spectroscopy","authors":"Yizhuang Xu","doi":"10.3233/BSI-150106","DOIUrl":"https://doi.org/10.3233/BSI-150106","url":null,"abstract":"","PeriodicalId":44239,"journal":{"name":"Biomedical Spectroscopy and Imaging","volume":"4 1","pages":"105-107"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3233/BSI-150106","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69855664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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