SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Masters Colin L.) "

Sökning: WFRF:(Masters Colin L.)

  • Resultat 1-10 av 15
  • [1]2Nästa
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Shaw, L. M., et al. (författare)
  • Method comparison study of the Elecsys® β-Amyloid (1–42) CSF assay versus comparator assays and LC-MS/MS
  • 2019
  • Ingår i: Clinical Biochemistry. - : Elsevier. - 0009-9120. ; 72:October, s. 7-14
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Alzheimer's disease (AD) biomarkers, such as cerebrospinal fluid (CSF) amyloid-β (1–42; Aβ42), can provide high diagnostic accuracy. Several immunoassays are available for Aβ42 quantitation, but standardisation across assays remains an issue. We compared the Elecsys® β-Amyloid (1–42) CSF assay with three assays and two liquid chromatography tandem mass spectrometry (LC-MS/MS) methods. Methods: Three method comparison studies evaluated the correlation between the Elecsys® β-Amyloid (1–42) CSF assay versus: INNOTEST® β-AMYLOID(1–42) (860 samples) and the Roche Diagnostics-developed LC-MS/MS method (250 samples); INNO-BIA AlzBio3 and the University of Pennsylvania (UPenn)-developed LC-MS/MS method (250 samples); and ADx-EUROIMMUN Beta-Amyloid (1–42) enzyme-linked immunosorbent assay (ELISA) (49 samples). Results: High correlation was demonstrated between Elecsys® β-Amyloid (1–42) CSF and comparator assays: INNOTEST® β-AMYLOID(1–42) (Spearman's ρ, 0.954); INNO-BIA AlzBio3 (Spearman's ρ, 0.864); ADx-EUROIMMUN Beta-Amyloid (1–42) ELISA (Pearson's r, 0.925). Elecsys® assay and LC-MS/MS measurements were highly correlated: Pearson's r, 0.949 (Roche Diagnostics-developed method) and 0.943 (UPenn-developed method). Conclusion: Findings from this multicentre evaluation further support use of the Elecsys® β-Amyloid (1–42) CSF assay to aid AD diagnosis. CSF-based certified reference materials should improve agreement across assays and mass spectrometry-based methods, which is essential to establish a global uniform CSF Aβ42 cut-off to detect amyloid pathology. © 2019
  •  
2.
  • Ashton, Nicholas J., et al. (författare)
  • A plasma protein classifier for predicting amyloid burden for preclinical Alzheimer's disease.
  • 2019
  • Ingår i: Science advances. - 2375-2548. ; 5:2
  • Tidskriftsartikel (refereegranskat)abstract
    • A blood-based assessment of preclinical disease would have huge potential in the enrichment of participants for Alzheimer's disease (AD) therapeutic trials. In this study, cognitively unimpaired individuals from the AIBL and KARVIAH cohorts were defined as Aβ negative or Aβ positive by positron emission tomography. Nontargeted proteomic analysis that incorporated peptide fractionation and high-resolution mass spectrometry quantified relative protein abundances in plasma samples from all participants. A protein classifier model was trained to predict Aβ-positive participants using feature selection and machine learning in AIBL and independently assessed in KARVIAH. A 12-feature model for predicting Aβ-positive participants was established and demonstrated high accuracy (testing area under the receiver operator characteristic curve = 0.891, sensitivity = 0.78, and specificity = 0.77). This extensive plasma proteomic study has unbiasedly highlighted putative and novel candidates for AD pathology that should be further validated with automated methodologies.
  •  
3.
  • Dhiman, Kunal, et al. (författare)
  • Cerebrospinal fluid neurofilament light concentration predicts brain atrophy and cognition in Alzheimer's disease.
  • 2020
  • Ingår i: Alzheimer's & dementia (Amsterdam, Netherlands). - 2352-8729. ; 12:1
  • Tidskriftsartikel (refereegranskat)abstract
    • This study assessed the utility of cerebrospinal fluid (CSF) neurofilament light (NfL) in Alzheimer's disease (AD) diagnosis, its association with amyloid and tau pathology, as well as its potential to predict brain atrophy, cognition, and amyloid accumulation.CSF NfL concentration was measured in 221 participants from the Australian Imaging, Biomarkers & Lifestyle Flagship Study of Ageing (AIBL).CSF NfL levels as well as NfL/amyloid β (Aβ42) were significantly elevated in AD compared to healthy controls (HC; P < .001), and in mild cognitive impairment (MCI) compared to HC (P = .008 NfL; P < .001 NfL/Aβ42). CSF NfL and NfL/Aβ42 differentiated AD from HC with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.84 and 0.90, respectively. CSF NfL and NfL/Aβ42 predicted cortical amyloid load, brain atrophy, and cognition.CSF NfL is a biomarker of neurodegeneration, correlating with cognitive impairment and brain neuropathology.
  •  
4.
  • Khan, Wasim, et al. (författare)
  • A Multi-Cohort Study of ApoE epsilon 4 and Amyloid-beta Effects on the Hippocampus in Alzheimer's Disease
  • 2017
  • Ingår i: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 56:3, s. 1159-1174
  • Tidskriftsartikel (refereegranskat)abstract
    • The apolipoprotein E (APOE) gene has been consistently shown to modulate the risk of Alzheimer's disease (AD). Here, using an AD and normal aging dataset primarily consisting of three AD multi-center studies (n = 1,781), we compared the effect of APOE and amyloid-beta (A beta) on baseline hippocampal volumes in AD patients, mild cognitive impairment (MCI) subjects, and healthy controls. A large sample of healthy adolescents (n = 1,387) was also used to compare hippocampal volumes between APOE groups. Subjects had undergone a magnetic resonance imaging (MRI) scan and APOE genotyping. Hippocampal volumes were processed using FreeSurfer. In the AD and normal aging dataset, hippocampal comparisons were performed in each APOE group and in epsilon 4 carriers with positron emission tomography (PET) A beta who were dichotomized (A beta+/A beta-) using previous cut-offs. We found a linear reduction in hippocampal volumes with epsilon 4 carriers possessing the smallest volumes, epsilon 3 carriers possessing intermediate volumes, and epsilon 2 carriers possessing the largest volumes. Moreover, AD and MCI epsilon 4 carriers possessed the smallest hippocampal volumes and control epsilon 2 carriers possessed the largest hippocampal volumes. Subjects with both APOE epsilon 4 and A beta positivity had the lowest hippocampal volumes when compared to A beta-epsilon 4 carriers, suggesting a synergistic relationship between APOE epsilon 4 and A beta. However, we found no hippocampal volume differences between APOE groups in healthy 14-year-old adolescents. Our findings suggest that the strongest neuroanatomic effect of APOE epsilon 4 on the hippocampus is observed in AD and groups most at risk of developing the disease, whereas hippocampi of old and young healthy individuals remain unaffected.
  •  
5.
  • Faux, Noel G, et al. (författare)
  • PBT2 Rapidly Improves Cognition in Alzheimer's Disease: Additional Phase II Analyses.
  • 2010
  • Ingår i: Journal of Alzheimer's disease : JAD. - 1875-8908 .- 1387-2877. ; 20:2, s. 509-16
  • Tidskriftsartikel (refereegranskat)abstract
    • PBT2 is a copper/zinc ionophore that rapidly restores cognition in mouse models of Alzheimer's disease (AD). A recent Phase IIa double-blind, randomized, placebo-controlled trial found that the 250 mg dose of PBT2 was well-tolerated, significantly lowered cerebrospinal fluid (CSF) levels of amyloid-beta_{42}, and significantly improved executive function on a Neuro-psychological Test Battery (NTB) within 12 weeks of treatment in patients with AD. In the post-hoc analysis reported here, the cognitive, blood marker, and CSF neurochemistry outcomes from the trial were subjected to further analysis. Ranking the responses to treatment after 12 weeks with placebo, PBT2 50 mg, and PBT2 250 mg revealed that the proportions of patients showing improvement on NTB Composite or Executive Factor z-scores were significantly greater in the PBT2 250 mg group than in the placebo group. Receiver-operator characteristic analyses revealed that the probability of an improver at any level coming from the PBT2 250 mg group was significantly greater, compared to placebo, for Composite z-scores (Area Under the Curve [AUC] =0.76, p=0.0007), Executive Factor z-scores (AUC =0.93, p=1.3 x 10;{-9}), and near-significant for the ADAS-cog (AUC =0.72, p=0.056). There were no correlations between changes in CSF amyloid-beta or tau species and cognitive changes. These findings further encourage larger-scale testing of PBT2 for AD.
  •  
6.
  • Naylor, Mary D, et al. (författare)
  • Advancing Alzheimer's disease diagnosis, treatment, and care: recommendations from the Ware Invitational Summit.
  • 2012
  • Ingår i: Alzheimer's & dementia : the journal of the Alzheimer's Association. - 1552-5279. ; 8:5, s. 445-52
  • Tidskriftsartikel (refereegranskat)abstract
    • To address the pending public health crisis due to Alzheimer's disease (AD) and related neurodegenerative disorders, the Marian S. Ware Alzheimer Program at the University of Pennsylvania held a meeting entitled "State of the Science Conference on the Advancement of Alzheimer's Diagnosis, Treatment and Care," on June 21-22, 2012. The meeting comprised four workgroups focusing on Biomarkers; Clinical Care and Health Services Research; Drug Development; and Health Economics, Policy, and Ethics. The workgroups shared, discussed, and compiled an integrated set of priorities, recommendations, and action plans, which are presented in this article.
  •  
7.
  • Cappai, Roberto, et al. (författare)
  • The amyloid precursor protein(APP)of Alzheimer's disease and its paralog APLP2 modulate the Cu/Zn-NO-catalyzed degradation of glypican-1 heparan sulfate In vivo.
  • 2005
  • Ingår i: Journal of Biological Chemistry. - : ASBMB. - 1083-351X. ; 280:14, s. 13913-13920
  • Tidskriftsartikel (refereegranskat)abstract
    • Processing of the recycling proteoglycan glypican-1 involves the release of its heparan sulfate chains by copper ion- and nitric oxide-catalyzed ascorbate-triggered autodegradation. The Alzheimer disease amyloid precursor protein (APP) and its paralogue, the amyloid precursor-like protein 2 (APLP2), contain copper ion-, zinc ion-, and heparan sulfate-binding domains. We have investigated the possibility that APP and APLP2 regulate glypican-1 processing during endocytosis and recycling. By using cell-free biochemical experiments, confocal laser immunofluorescence microscopy, and flow cytometry of tissues and cells from wild-type and knock-out mice, we find that (a) APP and glypican-1 colocalize in perinuclear compartments of neuroblastoma cells, (b) ascorbate-triggered nitric oxidecatalyzed glypican-1 autodegradation is zinc ion-dependent in the same cells, (c) in cell-free experiments, APP but not APLP2 stimulates glypican-1 autodegradation in the presence of both Cu(II) and Zn(II) ions, whereas the Cu(I) form of APP and the Cu(II) and Cu(I) forms of APLP2 inhibit autodegradation, (d) in primary cortical neurons from APP or APLP2 knock-out mice, there is an increased nitric oxide-catalyzed degradation of heparan sulfate compared with brain tissue and neurons from wild-type mice, and (e) in growth-quiescent fibroblasts from APLP2 knock-out mice, but not from APP knock-out mice, there is also an increased heparan sulfate degradation. We propose that the rate of autoprocessing of glypican-1 is modulated by APP and APLP2 in neurons and by APLP2 in fibroblasts. These observation identify a functional relationship between the heparan sulfate and copper ion binding activities of APP/APLP2 in their modulation of the nitroxyl anion-catalyzed heparan sulfate degradation in glypican-1.
  •  
8.
  • Insel, Philip S., et al. (författare)
  • Determining clinically meaningful decline in preclinical Alzheimer disease
  • 2019
  • Ingår i: Neurology. - : American Academy of Neurology. - 1526-632X. ; 93:4, s. 322-333
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE: To determine the time required for a preclinical Alzheimer disease population to decline in a meaningful way, use estimates of decline to update previous clinical trial design assumptions, and identify factors that modify β-amyloid (Aβ)-related decline. METHODS: In 1,120 cognitively unimpaired individuals from 3 international cohorts, we estimated the relationship between Aβ status and longitudinal changes across multiple cognitive domains and assessed interactions between Aβ and baseline factors. Power analyses were performed to explore sample size as a function of treatment effect. RESULTS: Cognitively unimpaired Aβ+ participants approach mild cognitive impairment (MCI) levels of performance 6 years after baseline, on average. Achieving 80% power in a simulated 4-year treatment trial, assuming a 25% treatment effect, required 2,000 participants/group. Multiple factors interacted with Aβ to predict cognitive decline; however, these findings were all cohort-specific. Despite design differences across the cohorts, with large sample sizes and sufficient follow-up time, the Aβ+ groups declined consistently on cognitive composite measures. CONCLUSIONS: A preclinical AD population declines to the cognitive performance of an early MCI population in 6 years. Slowing this rate of decline by 40%-50% delays clinically relevant impairment by 3 years-a potentially meaningful treatment effect. However, assuming a 40%-50% drug effect highlights the difficulties in preclinical AD trial design, as a more commonly assumed treatment effect of 25% results in a required sample size of 2,000/group. Designers of preclinical AD treatment trials need to prepare for larger and longer trials than are currently being considered. Interactions with Aβ status were inconsistent and not readily generalizable.
  •  
9.
  • Lannfelt, Lars, et al. (författare)
  • Safety, efficacy, and biomarker findings of PBT2 in targeting A beta as a modifying therapy for Alzheimer's disease : a phase IIa, double-blind, randomised, placebo-controlled trial
  • 2008
  • Ingår i: Lancet Neurology. - 1474-4422 .- 1474-4465. ; 7:9, s. 779-786
  • Tidskriftsartikel (refereegranskat)abstract
    • Background PBT2 is a metal-protein attenuating compound (MPAC) that affects the Cu2+-mediated and Zn2+-mediated toxic oligomerisation of A beta seen in Alzheimer's disease (AD). Strong preclinical efficacy data and the completion of early, clinical safety studies have preceded this phase IIa study, the aim of which was to assess the effects of PBT2 on safety, efficacy, and biomarkers of AD. Methods Between December 6, 2006, and September 21, 2007, community-dwelling patients over age 55 years were recruited to this 12-week, double-blind, randomised trial of PBT2. Patients were randomly allocated to receive 50 mg PBT2, 250 mg PBT2, or placebo. Inclusion criteria were early AD (mini-mental state examination [MMSE] score between 20 and 26 points or Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) score between 10 and 25 points), taking a stable dose of acetylcholinesterase inhibitor (donepezil, galantamine, or rivastigmine) for at least 4 months, a modified Hachinski score of 4 points or less, and CT or MRI results that were consistent with AD. The principal outcomes were safety and tolerability. Secondary outcomes were plasma and CSF biomarkers and cognition. Analysis was intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00471211. Findings 78 patients were randomly assigned (29 to placebo, 20 to PBT2 50 mg, and 29 to PBT2 250 mg) and 74 (95%) completed the study. 42 (54%) patients had at least one treatment emergent adverse event (10 [50%] on PBT2 50 mg, 18 [62%] on PBT2 250 mg, and 14 [48%] on placebo). No serious adverse events were reported by patients on PBT2. Patients treated with PBT2 250 mg had a dose-dependent (p=0.023) and significant reduction in CSF A beta(42) concentration compared with those treated with placebo (difference in least squares mean change from baseline was -56.0 pg/mL, 95% Cl -101.5 to -11.0; p=0.006). PBT2 had no effect on plasma biomarkers of AD or serum Zn2+ and Cu2+ concentrations. Cognition testing included ADAS-cog, MMSE, and a neuropsychological test battery (NTB). Of these tests, two executive function component tests of the NTB showed significant improvement over placebo in the PBT2 250 mg group: category fluency test (2.8 words, 0.1 to 5.4; p=0.041) and trail making part B (-48.0 s, -83.0 to -13.0; p=0.009). Interpretation The safety profile is favourable for the ongoing development of PBT2. The effect on putative biomarkers for AD in CSF but not in plasma is suggestive of a central effect of the drug on A beta metabolism. Cognitive efficacy was restricted to two measures of executive function. Future trials that are larger and longer will establish if the effects of PBT2 on biomarkers and cognition that are reported here translate into clinical effectiveness.
  •  
10.
  • Lannfelt, Lars, et al. (författare)
  • Safety, efficacy, and biomarker findings of PBT2 in targeting Abeta as a modifying therapy for Alzheimer's disease: a phase IIa, double-blind, randomised, placebo-controlled trial.
  • 2008
  • Ingår i: Lancet neurology. - 1474-4422. ; 7:9, s. 779-86
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: PBT2 is a metal-protein attenuating compound (MPAC) that affects the Cu2(+)-mediated and Zn2(+)-mediated toxic oligomerisation of Abeta seen in Alzheimer's disease (AD). Strong preclinical efficacy data and the completion of early, clinical safety studies have preceded this phase IIa study, the aim of which was to assess the effects of PBT2 on safety, efficacy, and biomarkers of AD. METHODS: Between December 6, 2006, and September 21, 2007, community-dwelling patients over age 55 years were recruited to this 12-week, double-blind, randomised trial of PBT2. Patients were randomly allocated to receive 50 mg PBT2, 250 mg PBT2, or placebo. Inclusion criteria were early AD (mini-mental state examination [MMSE] score between 20 and 26 points or Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) score between 10 and 25 points), taking a stable dose of acetylcholinesterase inhibitor (donepezil, galantamine, or rivastigmine) for at least 4 months, a modified Hachinski score of 4 points or less, and CT or MRI results that were consistent with AD. The principal outcomes were safety and tolerability. Secondary outcomes were plasma and CSF biomarkers and cognition. Analysis was intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00471211. FINDINGS: 78 patients were randomly assigned (29 to placebo, 20 to PBT2 50 mg, and 29 to PBT2 250 mg) and 74 (95%) completed the study. 42 (54%) patients had at least one treatment emergent adverse event (10 [50%] on PBT2 50 mg, 18 [62%] on PBT2 250 mg, and 14 [48%] on placebo). No serious adverse events were reported by patients on PBT2. Patients treated with PBT2 250 mg had a dose-dependent (p=0.023) and significant reduction in CSF Abeta(42) concentration compared with those treated with placebo (difference in least squares mean change from baseline was -56.0 pg/mL, 95% CI -101.5 to -11.0; p=0.006). PBT2 had no effect on plasma biomarkers of AD or serum Zn(2+) and Cu(2+) concentrations. Cognition testing included ADAS-cog, MMSE, and a neuropsychological test battery (NTB). Of these tests, two executive function component tests of the NTB showed significant improvement over placebo in the PBT2 250 mg group: category fluency test (2.8 words, 0.1 to 5.4; p=0.041) and trail making part B (-48.0 s, -83.0 to -13.0; p=0.009). INTERPRETATION: The safety profile is favourable for the ongoing development of PBT2. The effect on putative biomarkers for AD in CSF but not in plasma is suggestive of a central effect of the drug on Abeta metabolism. Cognitive efficacy was restricted to two measures of executive function. Future trials that are larger and longer will establish if the effects of PBT2 on biomarkers and cognition that are reported here translate into clinical effectiveness.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-10 av 15
  • [1]2Nästa
 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy