Biomedical Spectroscopy and Imaging最新文献_第10页

Anisotropy of spin-echo T2 relaxation by magnetic resonance imaging in the human brain in vivo 活体人脑磁共振成像自旋回波T2弛豫的各向异性

Biomedical Spectroscopy and Imaging Pub Date : 2015-06-30 DOI: 10.3233/BSI-150114

Michael J. Knight, B. Wood, Elizabeth Couthard, R. Kauppinen

{"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":null,"pages":null},"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}

引用次数: 34

Laurence Barron: The founding father of Raman optical activity. 劳伦斯·巴伦:拉曼光活性的奠基人。

Biomedical Spectroscopy and Imaging Pub Date : 2015-06-30 DOI: 10.3233/BSI-150119

P. Haris

引用次数: 1

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? 兔膝关节孤立性关节内骨损伤诱导前后血浆代谢谱:骨关节炎发病特征的潜力?

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-150122

Beata Mickiewicz, K. Huebner, Johnny K. Chau, N. Shrive, C. Frank, H. Vogel, D. Hart

{"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":null,"pages":null},"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}

引用次数: 0

The modified upconversion nanomaterials (UCNMs) for multimodal imaging and therapies 改良上转换纳米材料(UCNMs)用于多模态成像和治疗

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-150120

Xiaoqian Ge, Lining Sun, Liyi Shi, Ruoyan Wei

引用次数: 7

Determination of ulcer in the digestive tract using image analysis in wireless capsule endoscopy 无线胶囊内窥镜图像分析对消化道溃疡的诊断

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-150124

Jin Park, G. Yoon

引用次数: 1

FTIR microscopic imaging of carcinoma tissue section with 4× and 15× objectives: Practical considerations 4倍和15倍物镜下肿瘤组织切片的FTIR显微成像:实用性考虑

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-140101

C. Beleites, O. Guntinas-Lichius, G. Ernst, J. Popp, C. Krafft

{"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":null,"pages":null},"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}

引用次数: 2

DFT investigation of the vibrational properties of AT base pairs in the presence of Ca2+ and Mn2+ ions Ca2+和Mn2+离子存在下AT碱基对振动特性的DFT研究

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-150110

C. Tripon, C. Muntean, L. Buimaga-Iarinca, A. Calborean

引用次数: 0

Investigation of the elimination process of a multimodal polymer-shelled contrast agent in rats using ultrasound and transmission electron microscopy 利用超声和透射电镜研究多模态聚合物壳造影剂在大鼠体内的消除过程

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-140099

Johan Härmark, M. Larsson, A. Razuvajev, P. Koeck, G. Paradossi, L. Brodin, K. Caidahl, H. Hebert, A. Bjällmark

引用次数: 9

Biomolecular fingerprinting in the dried state 干燥状态下的生物分子指纹

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-150121

W. Wolkers, H. Oldenhof

引用次数: 0

Perspectives of optical coherence tomography imaging and Raman spectroscopy in cancer diagnosis 光学相干断层成像和拉曼光谱在癌症诊断中的应用前景

Biomedical Spectroscopy and Imaging Pub Date : 2015-01-01 DOI: 10.3233/BSI-140097

K. Divakar Rao, N.K. Sahoo, C. Murali Krishna

引用次数: 5