Chronic active multiple sclerosis lesions, characterized by a hyperintense rim of iron-enriched, activated microglia and macrophages, have been linked to greater tissue damage. Post-mortem studies have determined that chronic active lesions are primarily related to the later stages of multiple sclerosis; however, the occurrence of these lesions, and their relationship to earlier disease stages may be greatly underestimated. Detection of chronic active lesions across the patient spectrum of multiple sclerosis requires a validated imaging tool to accurately identify lesions with persistent inflammation. Quantitative susceptibility mapping provides efficient in vivo quantification of susceptibility changes related to iron deposition and the potential to identify lesions harbouring iron-laden inflammatory cells. The PET tracer 11 C-PK11195 targets the translocator protein expressed by activated microglia and infiltrating macrophages. Accordingly, this study aimed to validate that lesions with a hyperintense rim on quantitative susceptibility mapping from both relapsing and progressive patients demonstrate a higher level of innate immune activation as measured on 11 C-PK11195 PET. Thirty patients were enrolled in this study, 24 patients had relapsing remitting multiple sclerosis, six had progressive multiple sclerosis, and all patients had concomitant MRI with a gradient echo sequence and PET with 11 C-PK11195. A total of 406 chronic lesions were detected, and 43 chronic lesions with a hyperintense rim on quantitative susceptibility mapping were identified as rim + lesions. Susceptibility (relative to CSF) was higher in rim + (2.42 AE 17.45 ppb) compared to rimÀ lesions (À14.6 AE 19.3 ppb, P 5 0.0001). Among rim + lesions, susceptibility within the rim (20.04 AE 14.28 ppb) was significantly higher compared to the core (À5.49 AE 14.44 ppb, P 5 0.0001), consistent with the presence of iron. In a mixed-effects model, 11 C-PK11195 uptake, representing activated microglia/macrophages, was higher in rim + lesions compared to rimÀ lesions (P = 0.015). Validating our in vivo imaging results, multiple sclerosis brain slabs were imaged with quantitative susceptibility mapping and processed for immunohistochemistry. These results showed a positive translocator protein signal throughout the expansive hyperintense border of rim + lesions, which co-localized with iron containing CD68 + microglia and macrophages. In conclusion, this study provides evidence that suggests that a hyperintense rim on quantitative susceptibility measure within a chronic lesion is a correlate for persistent inflammatory activity and that these lesions can be identified in the relapsing patients. Utilizing quantitative susceptibility measure to differentiate chronic multiple sclerosis lesion subtypes, especially chronic active lesions, would provide a method to assess the impact of these lesions on disease progression.
Benign PI was slightly more prevalent than clinically worrisome PI in our cohort of patients with cancer. The presence of certain CT features (mesenteric stranding, bowel wall thickening, and ascites) and the location of PI may be indicators of more significant bowel disease and, therefore, of clinically worrisome cases. There was no statistical significance achieved for nonimaging clinical factors.
Determining the relationships between five-factor model (FFM) personality dimensions and Realistic, Investigative, Artistic, Social, Enterprising, and Conventional (RIASEC) types is important for counselors and clients during the career choice process. There have been mixed findings regarding this relationship, necessitating this research. The purpose of this study was to determine the relationship between the FFM and RIASEC interest types employing a multivariate meta-regression meta-analysis. Thirty-four studies with 43 independent samples comprising 19,872 participants were employed. Moderator variables included mean age, country of sample, publication year, and FFM and RIASEC Measurement Scales. Estimated correlations between FFM and RIASEC scores ranged from −.08 to .36 suggesting that personality and interests are more distinct constructs than previously thought. FFM Measurement Scales and RIASEC scores by country of sample are important moderating variables in the FFM-RIASEC relationship. The findings have important implications for counseling and research.
ObjectivesInvestigating the potential of myelin repair strategies in multiple sclerosis (MS) requires an understanding of myelin dynamics during lesion evolution. The objective of this study is to longitudinally measure myelin water fraction (MWF), an MRI biomarker of myelin, in new MS lesions and to identify factors that influence their subsequent myelin content.MethodsTwenty-three MS patients were scanned with whole-brain Fast Acquisition with Spiral Trajectory and T2prep (FAST-T2) MWF mapping at baseline and median follow-up of 6 months. Eleven healthy controls (HC) confirmed the reproducibility of FAST-T2 in white matter regions of interests (ROIs) similar to a lesion size. A random-effect-model was implemented to determine the association between baseline clinical and lesion variables and the subsequent MWF.ResultsROI-based measurements in HCs were highly correlated between scans [mean r = 0.893 (.764–.967)]. In MS patients, 38 gadolinium enhancing (Gd+) and 25 new non-enhancing (Gd−) T2 hyperintense lesions (5.7 months, ±3.8) were identified. Significant improvement in MWF was seen in Gd+ lesions (0.035 ± 0.029, p < 0.001) as compared to Gd− lesions (0.006 ± 0.017, p = 0.065). In the model, a higher baseline MWF (p < 0.001) and the presence of Gd (p < 0.001) were associated with higher subsequent MWF.ConclusionsFAST T2 provides a clinically feasible method to quantify MWF in new MS lesions. The observed influence of baseline MWF, which represents a combined effect of both resolving edema and myelin change within acute lesions, suggests that the extent of initial inflammation impacts final myelin recovery.
The relationship between career adaptability and career decision self-efficacy was examined due to its importance for clients in the career development and career decision-making process. Multivariate meta-analyses using 18 studies with a total population of 6,339 participants were employed. Moderator variables important to this relationship were country of participants, mean age, and career adaptability measures. Estimated correlations between career adaptability subscales and career decision self-efficacy measures ranged from .36 to .44. Findings are discussed in relation to career research and counseling.
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