| 41. |
- Homann, Jan, et al.
(författare)
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Genome-Wide Association Study of Alzheimer's Disease Brain Imaging Biomarkers and Neuropsychological Phenotypes in the European Medical Information Framework for Alzheimer's Disease Multimodal Biomarker Discovery Dataset.
- 2022
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Ingår i: Frontiers in aging neuroscience. - : Frontiers Media SA. - 1663-4365. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Alzheimer's disease (AD) is the most frequent neurodegenerative disease with an increasing prevalence in industrialized, aging populations. AD susceptibility has an established genetic basis which has been the focus of a large number of genome-wide association studies (GWAS) published over the last decade. Most of these GWAS used dichotomized clinical diagnostic status, i.e., case vs. control classification, as outcome phenotypes, without the use of biomarkers. An alternative and potentially more powerful study design is afforded by using quantitative AD-related phenotypes as GWAS outcome traits, an analysis paradigm that we followed in this work. Specifically, we utilized genotype and phenotype data from n = 931 individuals collected under the auspices of the European Medical Information Framework for Alzheimer's Disease Multimodal Biomarker Discovery (EMIF-AD MBD) study to perform a total of 19 separate GWAS analyses. As outcomes we used five magnetic resonance imaging (MRI) traits and seven cognitive performance traits. For the latter, longitudinal data from at least two timepoints were available in addition to cross-sectional assessments at baseline. Our GWAS analyses revealed several genome-wide significant associations for the neuropsychological performance measures, in particular those assayed longitudinally. Among the most noteworthy signals were associations in or near EHBP1 (EH domain binding protein 1; on chromosome 2p15) and CEP112 (centrosomal protein 112; 17q24.1) with delayed recall as well as SMOC2 (SPARC related modular calcium binding 2; 6p27) with immediate recall in a memory performance test. On the X chromosome, which is often excluded in other GWAS, we identified a genome-wide significant signal near IL1RAPL1 (interleukin 1 receptor accessory protein like 1; Xp21.3). While polygenic score (PGS) analyses showed the expected strong associations with SNPs highlighted in relevant previous GWAS on hippocampal volume and cognitive function, they did not show noteworthy associations with recent AD risk GWAS findings. In summary, our study highlights the power of using quantitative endophenotypes as outcome traits in AD-related GWAS analyses and nominates several new loci not previously implicated in cognitive decline.
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| 42. |
- Hong, Shengjun, et al.
(författare)
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Genome-wide association study of Alzheimer's disease CSF biomarkers in the EMIF-AD Multimodal Biomarker Discovery dataset.
- 2020
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Ingår i: Translational psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder and the most common form of dementia in the elderly. Susceptibility to AD is considerably determined by genetic factors which hitherto were primarily identified using case-control designs. Elucidating the genetic architecture of additional AD-related phenotypic traits, ideally those linked to the underlying disease process, holds great promise in gaining deeper insights into the genetic basis of AD and in developing better clinical prediction models. To this end, we generated genome-wide single-nucleotide polymorphism (SNP) genotyping data in 931 participants of the European Medical Information Framework Alzheimer's Disease Multimodal Biomarker Discovery (EMIF-AD MBD) sample to search for novel genetic determinants of AD biomarker variability. Specifically, we performed genome-wide association study (GWAS) analyses on 16 traits, including 14 measures derived from quantifications of five separate amyloid-beta (Aβ) and tau-protein species in the cerebrospinal fluid (CSF). In addition to confirming the well-established effects of apolipoprotein E (APOE) on diagnostic outcome and phenotypes related to Aβ42, we detected novel potential signals in the zinc finger homeobox 3 (ZFHX3) for CSF-Aβ38 and CSF-Aβ40 levels, and confirmed the previously described sex-specific association between SNPs in geminin coiled-coil domain containing (GMNC) and CSF-tau. Utilizing the results from independent case-control AD GWAS to construct polygenic risk scores (PRS) revealed that AD risk variants only explain a small fraction of CSF biomarker variability. In conclusion, our study represents a detailed first account of GWAS analyses on CSF-Aβ and -tau-related traits in the EMIF-AD MBD dataset. In subsequent work, we will utilize the genomics data generated here in GWAS of other AD-relevant clinical outcomes ascertained in this unique dataset.
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| 43. |
- Ingala, Silvia, et al.
(författare)
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Application of the ATN classification scheme in a population without dementia: Findings from the EPAD cohort.
- 2021
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Ingår i: Alzheimer's & dementia : the journal of the Alzheimer's Association. - : Wiley. - 1552-5279. ; 17:7, s. 1189-1204
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Tidskriftsartikel (refereegranskat)abstract
- We classified non-demented European Prevention of Alzheimer's Dementia (EPAD) participants through the amyloid/tau/neurodegeneration (ATN) scheme and assessed their neuropsychological and imaging profiles.From 1500 EPAD participants, 312 were excluded. Cerebrospinal fluid cut-offs of 1000 pg/mL for amyloid beta (Aß)1-42 and 27 pg/mL for p-tau181 were validated using Gaussian mixture models. Given strong correlation of p-tau and t-tau (R2 =0.98, P<0.001), neurodegeneration was defined by age-adjusted hippocampal volume. Multinomial regressions were used to test whether neuropsychological tests and regional brain volumes could distinguish ATN stages.Age was 65 ± 7 years, with 58% females and 38% apolipoprotein E (APOE) ε4 carriers; 57.1% were A-T-N-, 32.5% were in the Alzheimer's disease (AD) continuum, and 10.4% suspected non-Alzheimer's pathology. Age and cerebrovascular burden progressed with biomarker positivity (P<0.001). Cognitive dysfunction appeared with T+. Paradoxically higher regional gray matter volumes were observed in A+T-N- compared to A-T-N- (P<0.001).In non-demented individuals along the AD continuum, p-tau drives cognitive dysfunction. Memory and language domains are affected in the earliest stages.
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| 44. |
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| 45. |
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| 46. |
- Jin, Ying, et al.
(författare)
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"Soap bubble" sign as an imaging marker for posterior fossa ependymoma Group B
- 2023
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Ingår i: Neuroradiology. - : Springer. - 0028-3940 .- 1432-1920. ; 65, s. 1707-1714
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To investigate the predictive value of the "soap bubble" sign on molecular subtypes (Group A [PFA] and Group B [PFB]) of posterior fossa ependymomas (PF-EPNs).Methods: MRI scans of 227 PF-EPNs (internal retrospective discovery set) were evaluated by two independent neuroradiologists to assess the "soap bubble" sign, which was defined as clusters of cysts of various sizes that look like "soap bubbles" on T2-weighted images. Two independent cohorts (external validation set [n = 31] and prospective validation set [n = 27]) were collected to validate the "soap bubble" sign.Results: Across three datasets, the "soap bubble" sign was observed in 21 PFB cases (7.4% [21/285] of PF-EPNs and 12.9% [21/163] of PFB); none in PFA. Analysis of the internal retrospective discovery set demonstrated substantial interrater agreement (1st Rating: kappa = 0.71 [0.53-0.90], 2nd Rating: kappa = 0.83 [0.68-0.98]) and intrarater agreement (Rater 1: kappa = 0.73 [0.55-0.91], Rater 2: kappa = 0.74 [0.55-0.92]) for the "soap bubble" sign; all 13 cases positive for the "soap bubble" sign were PFB (p = 0.002; positive predictive value [PPV] = 100%, negative predictive value [NPV] = 44%, sensitivity = 10%, specificity = 100%). The findings from the external validation set and the prospective validation set were similar, all cases positive for the "soap bubble" sign were PFB (p < 0.001; PPV = 100%).Conclusion: The "soap bubble" sign represents a highly specific imaging marker for the PFB molecular subtype of PF-EPNs.
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| 47. |
- Jokinen, Hanna, et al.
(författare)
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Longitudinal cognitive decline in subcortical ischemic vascular disease--the LADIS Study.
- 2009
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Ingår i: Cerebrovascular diseases (Basel, Switzerland). - : S. Karger AG. - 1421-9786 .- 1015-9770. ; 27:4, s. 384-91
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Cross-sectional studies have indicated that subcortical ischemic vascular disease (SIVD), as defined according to imaging criteria, is associated with a specific clinical and cognitive profile. Much less is known about the long-term cognitive consequences of SIVD. The aim of the study was to investigate the longitudinal cognitive performance and incident dementia in subjects with and without SIVD in a sample of older adults with white matter lesions. METHODS: In the Leukoaraiosis and Disability (LADIS) study, 639 participants were examined with annual clinical and neuropsychological evaluations for 3 years. The subjects meeting the MRI criteria of SIVD at baseline were compared to the other subjects of the sample with linear mixed models. RESULTS: The overall level of cognitive performance over the follow-up period was inferior in multiple cognitive domains in SIVD subjects as compared to the reference group. The subjects with SIVD presented significantly steeper decline of performance in the Stroop test (parts I and II), Trail Making A test, Verbal fluency test, and Mini-Mental State Examination. They also had a threefold risk of developing dementia during follow-up independently of age, sex, education and medial temporal lobe atrophy. CONCLUSIONS: SIVD, as a manifestation of cerebral small vessel disease, is related to progressive cognitive impairment and a considerable risk of developing dementia. SIVD seems to specifically contribute to the deterioration of psychomotor speed, executive control, and global cognitive function.
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| 48. |
- Jokinen, Hanna, et al.
(författare)
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MRI-defined subcortical ischemic vascular disease: baseline clinical and neuropsychological findings. The LADIS Study.
- 2009
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Ingår i: Cerebrovascular diseases (Basel, Switzerland). - : S. Karger AG. - 1421-9786 .- 1015-9770. ; 27:4, s. 336-44
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Subcortical ischemic vascular disease (SIVD) is a common, but often overlooked cause of vascular cognitive impairment. Diagnostic research criteria for SIVD are based on magnetic resonance imaging (MRI) findings including substantial white matter lesions (WML) and multiple lacunar infarcts. Empirical studies validating these imaging criteria are still few. The purpose of the study was to describe the clinical and cognitive characteristics of the MRI-defined SIVD in a mixed sample of functionally independent elderly subjects with WML. METHODS: The subjects of the Leukoaraiosis and Disability (LADIS) study, aged 65-84 years, underwent comprehensive clinical and neuropsychological examinations, and brain MRI at the baseline assessment. The subjects meeting the SIVD imaging criteria (n = 89) were compared to the other subjects of the sample (n = 524). RESULTS: SIVD was associated with lower education, hypertension and, independently, with obesity. The subjects with SIVD had more often motor impairment, a history of falls, and subtle impairment in activities of daily living, but they did not differ for depressive symptoms. SIVD subjects performed significantly inferiorly in tests of global cognitive function, psychomotor speed, attention and executive functions, verbal fluency, and working memory. CONCLUSION: In this population of nondisabled older adults with WML, SIVD was related to specific clinical and functional characteristics. Neuropsychological features included psychomotor slowing as well as deficits in attention and executive functions.
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| 49. |
- Killestein, Joep, et al.
(författare)
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Antibody-Mediated suppression of Vbeta5.2/5.3+ T Cells in Multiple Sclerosis : Results from an MRI-Monitored Phase II Clinical Trial
- 2002
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Ingår i: Annals of Neurology. - : Wiley. - 0364-5134 .- 1531-8249. ; 51, s. 467-
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to evaluate the safety and efficacy of the humanized antibody ATM-027 in a baseline versus treatment magnetic resonance imaging-monitored study. Expansion of Vß5.2/5.3+ T cells has been demonstrated in the peripheral blood, cerebrospinal fluid, and brain lesions of MS patients. In a phase I study, ATM-027 depleted these cells in peripheral blood and, in parallel, T-cell MBP reactivity and IFN-? expression were reduced. We studied 59 patients with relapsing-remitting MS (47 on ATM-027 and 12 on placebo) stratified for HLA-DR2 status. Monthly intravenous injections were given for 6 months. Individual dose titration was employed to obtain depletion of the target T-cell level and downregulation of antigen receptor density as monitored by flow cytometry. Five monthly magnetic resonance imaging scans were performed before treatment to establish baseline activity, six during treatment, and three during follow-up. Additional immunological assessments were performed to elucidate the mechanism of action of ATM-027. The treatment was safe and well tolerated, inducing consistent suppression of the target cell population. During run-in, active lesions were found in 78.7% (37/47) of patients treated with ATM-027. During treatment, the median number of lesions was reduced by 33% (p = 0.13) independent of DR2 status. The corresponding volume of enhancement was 221 mm3 at baseline, with a reduction of 10% during treatment. Decreased numbers of cells expressing interferon-? messenger RNA, and decreased T-cell reactivity to several myelin antigens were found in ATM-027 treated patients. In conclusion, consistent suppression of Vß 5.2/5.3+ T cells was achieved. However, the effect size on magnetic resonance imaging was considerably less than the targeted 60%.
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| 50. |
- Kim, Min, et al.
(författare)
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Primary fatty amides in plasma associated with brain amyloid burden, hippocampal volume, and memory in the European Medical Information Framework for Alzheimer's Disease biomarker discovery cohort
- 2019
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Ingår i: Alzheimer's & Dementia. - : Elsevier. - 1552-5260 .- 1552-5279. ; 15:6, s. 817-827
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: A critical and as-yet unmet need in Alzheimer's disease (AD) is the discovery of peripheral small molecule biomarkers. Given that brain pathology precedes clinical symptom onset, we set out to test whether metabolites in blood associated with pathology as indexed by cerebrospinal fluid (CSF) AD biomarkers.METHODS: This study analyzed 593 plasma samples selected from the European Medical Information Framework for Alzheimer's Disease Multimodal Biomarker Discovery study, of individuals who were cognitively healthy (n = 242), had mild cognitive impairment (n = 236), or had AD-type dementia (n = 115). Logistic regressions were carried out between plasma metabolites (n = 883) and CSF markers, magnetic resonance imaging, cognition, and clinical diagnosis.RESULTS: Eight metabolites were associated with amyloid β and one with t-tau in CSF, these were primary fatty acid amides (PFAMs), lipokines, and amino acids. From these, PFAMs, glutamate, and aspartate also associated with hippocampal volume and memory.DISCUSSION: PFAMs have been found increased and associated with amyloid β burden in CSF and clinical measures.
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