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541.
Form and function of the intervertebral disc in health and disease: a morphological and stain comparison study
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B. A. Walter O. M. Torre D. Laudier T. P. Naidich A. C. Hecht J. C. Iatridis 《Journal of anatomy》2015,227(6):707-716
Multiple histologic measurements are commonly used to assess degenerative changes in intervertebral disc (IVD) structure; however, there is no consensus on which stains offer the clearest visualization of specific areas within the IVD. The objective of this study was to compare multiple tinctorial stains, evaluate their ability to highlight structural features within the IVD, and investigate how they influence the capacity to implement a degeneration scoring system. Lumbar IVDs from seven human autopsy specimens were stained using six commonly used stains (Hematoxylin/Eosin, Toluidine Blue, Safranin‐O/Fast Green, Extended FAST, modified Gomori''s Trichrome, and Picrosirius Red Alcian Blue). All IVDs were evaluated by three separate graders to independently determine which stains (i) were most effective at discerning different structural features within different regions of the IVDs and (ii) allowed for the most reproducible assessment of degeneration grade, as assessed via the Rutges histological scoring system (Rutges et al. A validated new histological classification for intervertebral disc degeneration. Osteoarthritis Cartilage, 21, 2039‐47). Although Trichrome, XFAST and PR/AB stains were all effective at highlighting different regions of whole IVDs, we recommend the use of PR/AB because it had the highest degree of rater agreement on assigned degeneration grade, allowed greater resolution of degeneration grade, has an inferential relationship between color and composition, and allowed clear differentiation of the different regions and structural disruptions within the IVD. The use of a standard set of stains together with a histological grading scheme can aid in the characterization of structural changes in different regions of the IVD and may simplify comparisons across the field. This collection of human IVD histological images highlights how IVD degeneration is not a single disease but a composite of multiple processes such as aging, injury, repair, and disease, each of which are unique to the individual. 相似文献
542.
Mark E. Molitch Laura Cowen Raymond Stadiem Alexander Uihlein Michelle Naidich Eric Russell 《Pituitary》2012,15(4):598-600
There is a clinical impression that when tumors invade the cavernous sinus, compression of the internal carotid artery is rare with pituitary adenomas and more common with other types of lesions but there are no actual data to support this impression. To confirm the impression that the finding of internal carotid artery compression by tumors invading the cavernous sinus is inconsistent with a diagnosis of a pituitary adenoma, we performed a retrospective analysis of MRI scans performed between 2000 and July 2009. An initial search of the radiology database was performed using the terms ??invasive mass cavernous MRI?? and subsequent refinement narrowed the evaluation to 141 patients with cavernous sinus invasion by sellar/parasellar tumors for whom there were clinical/pathological data to determine tumor type. 83 of the 141 patients with cavernous sinus invasion had carotid artery encasement; 58 were pituitary adenomas and 25 were other types of lesions. Eight of these 83 scans revealed compression of the internal carotid lumen, with only one being a pituitary adenoma and seven being other types of lesions. Therefore, only 1/58 (1.7%) of pituitary adenomas and 7/25 (28%) of non-pituitary adenoma lesions that encased the internal carotid artery caused compression of the artery (P?=?0.0007). A mass lesion that invades the cavernous sinus and encases the internal carotid artery is very unlikely, therefore, to be a pituitary adenoma if it compresses the lumen of the internal carotid artery. 相似文献
543.
Germline deletions in the tumour suppressor gene FOCAD are associated with polyposis and colorectal cancer development
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Robbert DA Weren Ramprasath Venkatachalam Jean‐Baptiste Cazier Henner F Farin C Marleen Kets Richarda M de Voer Lilian Vreede Eugène TP Verwiel Monique van Asseldonk Eveline J Kamping Lambertus A Kiemeney Kornelia Neveling Katja KH Aben Luis Carvajal‐Carmona Iris D Nagtegaal Hans K Schackert Hans Clevers Marc van de Wetering Ian P Tomlinson Marjolijn JL Ligtenberg Nicoline Hoogerbrugge Ad Geurts van Kessel Roland P Kuiper 《The Journal of pathology》2015,236(2):155-164
Heritable genetic variants can significantly affect the lifetime risk of developing cancer, including polyposis and colorectal cancer (CRC). Variants in genes currently known to be associated with a high risk for polyposis or CRC, however, explain only a limited number of hereditary cases. The identification of additional genetic causes is, therefore, crucial to improve CRC prevention, detection and treatment. We have performed genome‐wide and targeted DNA copy number profiling and resequencing in early‐onset and familial polyposis/CRC patients, and show that deletions affecting the open reading frame of the tumour suppressor gene FOCAD are recurrent and significantly enriched in CRC patients compared with unaffected controls. All patients carrying FOCAD deletions exhibited a personal or family history of polyposis. RNA in situ hybridization revealed FOCAD expression in epithelial cells in the colonic crypt, the site of tumour initiation, as well as in colonic tumours and organoids. Our data suggest that monoallelic germline deletions in the tumour suppressor gene FOCAD underlie moderate genetic predisposition to the development of polyposis and CRC. © 2015 Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
544.
Population based standards for pulmonary function in non-smoking adults in Singapore 总被引:1,自引:0,他引:1
Abstract Ethnic differences in lung function are well recognized, hence the use of normative data should therefore be based on reference equations that are derived specifically for different ethnic groups. We have collected data ( n =406) for population-based reference values of lung function from randomly selected samples of healthy non-smoking adults of both gender (aged 20–79 years) for each of the three major ethnic groups (Chinese, Malay and Indians) in Singapore. Lung function forced expiratory volume in 1 second (FEV1 ), forced vital capacity (FVC), FEV1 /FVC, diffusion capacity (transfer factor) for carbon monoxide (DLCO), total lung capacity (TLC), residual volume (RV), RV/TLC and functional residual capacity (FRC) was measured using standardization procedures and acceptability criteria recommended by the American Thoracic Society. Lung function values were predicted from age, height, weight, body mass index (BMI) and transformed variables of these anthropometric measures, using multiple regression techniques. Ethnic differences were demonstrated, with Chinese having the largest lung volumes and flow rates, and Indians the smallest. These prediction equations provide improved and additional (TLC, RV, RV/TLC, FRC) population-based reference values for assessment of pulmonary health and disease in Singapore 相似文献
545.
546.
Myrna C.B. Godoy Samantha L. HellerDavid P. Naidich Bernard AssadourianChristianne Leidecker Bernhard SchmidtIoannis Vlahos 《European journal of radiology》2011,79(2):e11
Purpose
The aim of this study was (a) to compare arterial enhancement in simultaneously acquired high- and low-kilovoltage images; and (b) to determine whether low tube-voltage imaging would permit PE evaluation on routine chest CT studies or CTPA studies performed with a low volume of contrast media.Materials and methods
We compared 20 CTPA studies (CTPA group), 20 routine thoracic CT studies (RT group) and 10 CTPA studies performed with reduced volume of contrast media (RC group). HU values were measured in all groups at 80 kVp and 140 kVp images in multiple pulmonary arterial segments bilaterally. The diagnostic quality of the central and peripheral vascular enhancement and the image noise were evaluated at both energies using a five-point scale.Results
For all patients, the mean CT attenuation values were greater at 80 kVp than 140 kVp images (p < 0.001). At 80 kVp, CTPA group attenuation values were greater than RT group (p = 0.03) with a similar trend at 140 kVp (p = 0.08). At both 140 kVp and 80 kVp, CTPA group attenuation values were greater than RC group (p = 0.02 and p = 0.03, respectively). Qualitative analysis showed that at 140 kVp CTPA studies had better global image quality scores than RT (p = 0.003) and RC (p = 0.001) groups. However, at 80 kVp, there was no significant difference of global image quality between CTPA and the other groups (p = 0.4 and p = 0.5, respectively). Although measurable image noise was greater at 80 kVp than 140 kVp (p < 0.001), qualitative analysis revealed lower image noise at 80 kVp images.Conclusion
DECT at 80 kVp increases arterial enhancement in both CTPA and routine studies. For routine studies this results in central and peripheral enhancement quality equivalent to that of CTPA studies. Low tube-voltage imaging allows marked contrast volume reduction for CTPA. In selected cases, satisfactory lower radiation dose CT might be achievable using lower kVp imaging alone. 相似文献547.
With continued improvement of high-resolution multidetector computed tomography imaging, there is an increasing number of unsuspected thoracic findings. Although?many of these findings are of little clinical significance, other findings such as small incidental lung nodules require additional imaging to exclude more worrisome causes, often resulting in greater exposure to ionizing radiation, increased cost, and patient anxiety. Although greater uniformity among radiologists regarding likely benign findings may help reduce unnecessary imaging studies, the lack of clear follow-up guidelines for many findings suggests that further investigation is needed in some areas. 相似文献
548.
Elegance TP Lam Cindy LK Lam CL Lai MF Yuen Daniel YT Fong Thomas MK So 《Health and quality of life outcomes》2009,7(1):52
Background
Few studies have evaluated the health-related quality of life (HRQOL) of Southern Chinese with chronic hepatitis B (CHB) infection. 相似文献549.
Greenberg AK Rimal B Felner K Zafar S Hung J Eylers E Phalan B Zhang M Goldberg JD Crawford B Rom WN Naidich D Merali S 《Chest》2007,132(4):1247-1252
BACKGROUND: S-Adenosylmethionine (AdoMet) is a major methyl donor for transmethylation reactions and propylamine donor for the biosynthesis of polyamines in biological systems, and therefore may play a role in lung cancer development. We hypothesized that AdoMet levels were elevated in patients with lung cancer and may prove useful as a biomarker for early lung cancer. METHODS: High-performance liquid chromatography was used to analyze plasma AdoMet levels in triplicate samples from 68 patients. This included 13 patients with lung cancer, 33 smokers with benign lung disease, and 22 healthy nonsmokers. The three groups of subjects were compared with respect to the distribution of demographic and disease characteristics and AdoMet levels. Distributions were examined using summary statistics and box plots, and nonparametric analysis of variance procedures. RESULTS: Serum AdoMet levels were elevated in patients with lung cancer as compared to smokers with benign lung disorders and healthy nonsmokers. There were no significant correlations between AdoMet levels and tumor cell types, nodule size, or other demographic variables. CONCLUSIONS: Our data demonstrate that plasma levels of AdoMet are significantly elevated in patients with lung cancer. Plasma AdoMet levels may prove to be a useful tool for the diagnosis of early lung cancer, in combination with chest CT. Registered at: clinicaltrials.gov (NCT00301119). 相似文献