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Background
The purpose of our investigation was to compare quantitative T2 relaxation time measurement evaluation of lumbar intervertebral discs with morphological grading in young to middle-aged patients with low back pain, using a standardized region-of-interest evaluation approach.Patients and methods
Three hundred thirty lumbar discs from 66 patients (mean age, 39 years) with low back pain were examined on a 3.0 T MR unit. Sagittal T1-FSE, sagittal, coronal, and axial T2-weighted FSE for morphological MRI, as well as a multi-echo spin-echo sequence for T2 mapping, were performed. Morphologically, all discs were classified according to Pfirrmann et al. Equally sized rectangular regions of interest (ROIs) for the annulus fibrosus were selected anteriorly and posteriorly in the outermost 20% of the disc. The space between was defined as the nucleus pulposus. To assess the reproducibility of this evaluation, inter- and intraobserver statistics were performed.Results
The Pfirrmann scoring of 330 discs showed the following results: grade I: six discs (1.8%); grade II: 189 (57.3%); grade III: 96 (29.1%); grade IV: 38 (11.5%); and grade V: one (0.3%). The mean T2 values (in milliseconds) for the anterior and the posterior annulus, and the nucleus pulposus for the respective Pfirrmann groups were: I: 57/30/239; II: 44/67/129; III: 42/51/82; and IV: 42/44/56. The nucleus pulposus T2 values showed a stepwise decrease from Pfirrmann grade I to IV. The posterior annulus showed the highest T2 values in Pfirrmann group II, while the anterior annulus showed relatively constant T2 values in all Pfirrmann groups. The inter- and intraobserver analysis yielded intraclass correlation coefficients (ICC) for average measures in a range from 0.82 (anterior annulus) to 0.99 (nucleus).Conclusions
Our standardized method of region-specific quantitative T2 relaxation time evaluation seems to be able to characterize different degrees of disc degeneration quantitatively. The reproducibility of our ROI measurements is sufficient to encourage the use of this method in future investigations, particularly for longitudinal studies. 相似文献Methods: From July to September 2015, a survey link was emailed to journal editors identified from the Thomson Reuters registry. Editors ranked their perception of: a) change in transparency and credibility of industry-sponsored clinical trial publications; b) 8 “Publication Best Practices” and the impact of each on transparency; and c) the importance and adoption of the previously published “10 Recommendations for Closing the Credibility Gap in Reporting Industry-Sponsored Clinical Research”.
Results: Of 510 editors who opened the survey, the analysis pool comprised a total of 293 editors. The majority of respondents reported their location as the US (46%) or EU (45%) and most commonly reported editorial titles were deputy/assistant editor (36%), editor-in-chief (35%) and section editor (24%). More editors reported improved versus worsened transparency (63.5% vs. 6.1%) and credibility (53.2% vs. 10.4%). Best practices that contributed most to improved transparency were “disclosure of the study sponsor” and “registration and posting of trial results”. Respondents ranked the importance of nine recommendations as moderate or extremely important, and adoption of all recommendations was ranked minimal to moderate.
Conclusions: The 293 editors who responded perceived an improvement in the transparency and credibility of industry-sponsored publications from 2010 to 2015. Confirmation of the importance of 9/10 recommendations by the respondents was encouraging. Yet, low adoption rates suggest that additional work is required by all stakeholders to improve best practices, transparency and credibility. 相似文献
Methods: Ten female Sprague Dawley rats, 9 weeks old, were randomly divided into two groups and fed either standard laboratory chow or food rich in saturated fatty acids during 6 weeks and then mated with the same male rat. After birth and lactation male rat offspring from both groups were divided into four subgroups depending on the diet they were fed until 22 weeks old. Samples of white adipose tissue were taken from the subcutaneous, epididymal, and perirenal fat pad. On tissue sections, histomorphometric analysis was conducted using CellProfiler program v 2.1.1, and immunohistochemical staining for TNF-α was performed.
Results: Greater mean surface area of subcutaneous and epididymal adipocytes was found in groups of male rat offspring with altered diet. In perirenal adipose tissue, the highest number of adipocytes was measured in the group where both mother and offspring were fed a high-fat diet. Adipocyte staining intensity for TNF-α did not differ significantly between the groups.
Conclusions: Together with our previously published data, our results lead to the conclusion that alteration of postnatal diet can lead to TNF-α and adipocyte morphology changes. 相似文献