Summary Objective To evaluate the longitudinal reproducibility and variations of cartilage T1ρ and T2 measurements using different coils, MR systems and sites. Methods Single-Site study : Phantom ...data were collected monthly for up to 29 months on four GE 3T MR systems. Data from phantoms and human subjects were collected on two MR systems using the same model of coil; and were collected on one MR system using two models of coils. Multi-site study: Three participating sites used the same model of MR systems and coils, and identical imaging protocols. Phantom data were collected monthly. Human subjects were scanned and rescanned on the same day at each site. Two traveling human subjects were scanned at all three sites. Results Single-Site Study : The phantom longitudinal RMS-CVs ranged from 1.8% to 2.7% for T1ρ and 1.8–2.8% for T2 . Significant differences were found in T1ρ and T2 values using different MR systems and coils. Multi-Site Study: The phantom longitudinal RMS-CVs ranged from 1.3% to 2.6% for T1ρ and 1.2–2.7% for T2 . Across three sites ( n = 16), the in vivo scan-rescan RMS-CV was 3.1% and 4.0% for T1ρ and T2 , respectively. Phantom T1ρ and T2 values were significantly different between three sites but highly correlated ( R > 0.99). No significant difference was found in T1ρ and T2 values of traveling controls, with cross-site RMS-CV as 4.9% and 4.4% for T1ρ and T2 , respectively. Conclusion With careful quality control and cross-calibration, quantitative MRI can be readily applied in multi-site studies and clinical trials for evaluating cartilage degeneration.
Cite this as: H. Miyahara, N. Okazaki,T. Nagakura, S. Korematsu and T. Izumi,Clinical & Experimental Allergy, 2011 (41) 186–191.
Summary
Background
Thymus‐and‐activation‐regulated chemokine (TARC; ...CCL17) is related to both allergy and pregnancy, but the relationships of maternal and umbilical cord blood CCL17 to atopic dermatitis (AD) development have not yet been examined.
Objective
Seventy paired full‐term and normal vaginal delivery newborns and their mothers were enrolled in this study.
Methods
To elucidate the pathogenesis and fetomaternal inheritance of AD in infancy, CCL17, IFN‐γ‐inducible protein 10 kDa (IP‐10; CXCL10), soluble HLA‐G (sHLA‐G), IgE and eosinophil counts were examined using sera from 70 paired umbilical cord and maternal blood samples.
Results
Serum CCL17 (rs=0.340, P<0.001) and sHLA‐G (rs=0.600, P<0.001) levels showed high correlations between umbilical cord and maternal blood. Umbilical cord serum levels of CCL17 from neonates destined to develop AD in infancy were higher than in those from neonates who showed no signs of AD during infancy (median 1586.9 vs. 819.6 pg/mL, P<0.001). Serum levels of CCL17 were higher in mothers with AD than in those without AD (median 909.6 vs. 214.1 pg/mL, P<0.001). High umbilical cord serum levels of CCL17 were associated with infantile AD development even in 62 neonates born to mothers without AD (median 1514.4 vs. 740.6 pg/mL, P<0.001) and 38 neonates born to mothers with no allergies (median 1624.2 vs. 740.6 pg/mL, P<0.001). The summary estimates for umbilical cord serum CCL17 in the diagnosis of infantile AD were: sensitivity 85.7% (95% confidence interval: 72.8–98.7), specificity 73.8% (60.5–87.1), positive predictive value 68.6% (53.2–84.0) and negative predictive value 88.6% (78.0–99.1).
Conclusion and Clinical Relevance
These findings suggest that the umbilical cord blood CCL17 may be involved in the pathogenesis of infantile AD and in fetomaternal inheritance. Serum levels of CCL17 from umbilical cord blood may be a predictive marker for AD in infancy.
We have developed a technique for neutron diffraction experiments at pressures up to 40 GPa using a Paris-Edinburgh press at the PLANET beamline in J-PARC. To increase the maximum accessible ...pressure, the diameter of the dimple for sample chamber at the top of the sintered diamond anvils is sequentially reduced from 4.0 mm to 1.0 mm. As a result, the maximum pressure increased and finally reached 40 GPa. By combining this technique with the beam optics which defines the gauge volume, diffraction patterns sufficient for full-structure refinements are obtainable at such pressures.
Summary
Subchondral trabecular bone structure was analyzed in knee osteoarthritis (OA) patients using 3-T MRI to investigate structural features of subchondral trabecular bone of knee OA. With OA ...progression, osteoporotic changes were observed in the lateral joint, showing a higher correlation than sclerotic changes in the medial joint.
Introduction
To investigate structural features of subchondral trabecular bone of knee osteoarthritis (OA).
Methods
Sixty knees with KL grade 0–4 (all female) were examined. Fast imaging employing steady-state acquisition-cycled phases (FIESTA-c) and FatSat Spoiled gradient recalled acquisition in the steady state (SPGR) images were acquired by 3-T MRI. At four sites (the medial femur, medial tibia, lateral femur, and lateral tibia), subchondral trabecular bone structure was analyzed by FIESTA-c imaging, cartilage area was measured by SPGR imaging, and their correlation was analyzed. In addition, the subjects were classified into four groups from the cartilage area measured by SPGR imaging, and subchondral trabecular bone structure in each group was compared.
Results
As cartilage area decreased in the medial joint, bone volume fraction and trabecular thickness in the medial tibia increased, and bone volume fraction, trabecular thickness, number, and connectivity in the lateral femur and lateral tibia decreased (
r
≥ 0.4 or ≤−0.4,
p
≤ 0.001). Compared to medially, the changes laterally showed a higher correlation. When the medial-lateral ratio of trabecular thickness in the tibia was determined, it had the highest correlation coefficient (
r
=−0.7,
p
< 0.001). These changes were not significantly detected in the early stage.
Conclusions
To more sensitively detect OA changes in subchondral trabecular bone structure, a focus on osteoporotic changes in the lateral joint and the medial-lateral ratio would be useful. Detectability of early OA remains unknown, but based on a strong correlation with the degree of OA progression, trabecular structural analysis of subchondral bone may be a useful parameter to evaluate OA severity and evaluate treatment.
In the present study, the adhesive strength of scarf joint is examined by using the stress intensity factor of the fictitious small interface crack. The stress intensity factor of small crack near ...the interface edge is dominated by the singular stress field of the interface corner. In this study, to evaluate the joint strength, small crack is assumed at the interface corner of the scarf joint. The stress intensity factor of the interfacial crack is calculated by changing the thickness of the adhesive layer and the scarf angle. By using the experimental fracture strength of the scarf adhesive joint specimens under tension, the values of the critical stress intensity factor are calculated. From the analysis result, when the combination of adhesive materials and the scarf angle are fixed, the critical stress intensity factors of the small interface crack are constant value irrespective of the adhesive layer thickness. Therefore, the adhesive joint strength can be evaluated as the constant stress intensity factor of small interface crack. In addition, it is possible to evaluate easily the stress intensity factor by using the dimensionless coefficients depending only on the material combination when the crack length is sufficiently smaller than the thickness of the adhesive layer. The effects of adhesive layer thickness and adhesion angle of scarf joint specimen were discussed and the effectiveness of the proposed method was indicated.
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