Biomarkers relevant to the pre-dementia stages of Alzheimer’s disease are needed. Using MEG, PET, and MRI, Nakamura et al. disentangle resting state regional spectral patterns in cognitively normal subjects and individuals with mild cognitive impairment into MEG signatures related to Aβ deposition, disease progression, or changes non-specific to Alzheimer’s disease.
Alzheimer’s disease (AD) is the most common and devastating dementia. Simple and practical biomarkers for AD are urgently required for accurate diagnosis and to facilitate the development of disease-modifying interventions. The subjects for the study were selected on the basis of PiB amyloid imaging by PET. Forty PiB-positive (PiB+) individuals, including cognitively healthy controls (HC), and mild cognitive impairment and AD individuals, and 22 PiB-negative (PiB−) HC participated. Employing our novel highly sensitive immunoprecipitation-mass spectrometry, we measured plasma amyloid β-proteins (Aβs; Aβ1-40 and Aβ1-42) and Aβ-approximate peptides (AβAPs), which were cleaved from amyloid precursor protein (APP). Among the AβAPs, APP669-711 appeared to be a good reference for deciphering pathological change of Aβ1-42. We evaluated the performance of the ratio of APP669-711 to Aβ1-42 (APP669-711/Aβ1-42) as a biomarker. APP669-711/Aβ1-42 significantly increased in the PiB+ groups. The sensitivity and specificity to discriminate PiB+ individuals from PiB− individuals were 0.925 and 0.955, respectively. Our plasma biomarker precisely surrogates cerebral amyloid deposition.
The cellular distribution of malondialdehyde (MDA) was assessed immunohistochemically in brain specimens from young and normal elderly subjects as well as patients with Alzheimer's disease (AD). MDA was increased in the cytoplasm of neurons and astrocytes in both normal aging and AD, but was rarely detected in normal young subjects. By electron microscopic immunohistochemistry, neuronal MDA formed cap-like linear deposits associated with lipofuscin, while glial MDA deposits surrounded the vacuoles in a linear distribution. In the hippocampus, neuronal and glial MDA deposition was marked in the CA4 region but mild in CA1. By examination of serial sections stained with anti-MDA and antibodies against an advanced glycation end product, N(epsilon)-(carboxymethyl)lysine (CML), neuronal and glial MDA deposition was colocalized with CML in AD, but only neuronal MDA was colocalized with CML in normal aged brains. Glial MDA, although abundant in the aged brain, typically was not colocalized with CML. In AD cases, MDA was colocalized with tau protein in CA2 hippocampal neurons; such colocalization was rare in CA1. MDA also was stained in cores of senile plaques. Thus, while both MDA and CML accumulate under oxidative stress, CML accumulation is largely limited to neurons, in normal aging, while MDA also accumulates in glia. In AD, both MDA and CML are deposited in both astrocytes and neurons.
Machado-Joseph disease patients have verbal and visual memory deficits, visuospatial and constructional dysfunction, and verbal fluency deficits, all unrelated to CAG repeat length.
Cardiac
123I-meta-iodobenzylguanidine (MIBG) uptake was measured in 11 patients with dementia with Lewy bodies (DLB), 10 patients with Alzheimer's disease (AD), and 10 age matched control subjects. The severity of cognitive impairment and duration of symptoms in patients with DLB matched that in the patients with AD. The heart/mediastinum (H/M) ratio of MIBG uptake in the patients with AD was indistinguishable from that in the control subjects. However, the H/M ratio in all patients with DLB was significantly lower than that in the patients with AD and control subjects (p<0.001). These findings indicate that local myocardial sympathetic nerves are aVected in DLB and that cardiac 123 I-MIBG scintigraphy may provide a means of diVerentiating DLB from AD. (J Neurol Neurosurg Psychiatry 2001;70:781-783)
NVA237 is a once-daily inhaled long-acting muscarinic antagonist in development for the treatment of COPD. This randomized, double-blind, placebo-controlled, four-period, incomplete block crossover study, with open-label active comparator (tiotropium), assessed the efficacy and safety of NVA237. Patients (>or=40 years; smoking history >or=10 pack-years) with stable moderate-to-severe COPD (post-bronchodilator FEV(1) >or= 30% and <80% predicted, FEV(1)/FVC < 0.7) received NVA237 12.5, 25, 50 or 100 microg, placebo, or tiotropium 18 microg once-daily for 7 days. The primary endpoint was mean trough (23-24 h post-dose) FEV(1) on Day 7. Secondary endpoints included mean trough FEV(1) on Day 1, and FEV(1) and FVC at individual time points post-dose on Days 1 and 7. 83 patients (mean age 64.4 years; male 83.1%; mean COPD duration 6.7 years; mean post-bronchodilator FEV(1) 1.5 L/52.7% predicted) were randomized; 78 completed. Mean trough FEV(1) on Day 7 and Day 1 was significantly higher with all active treatments versus placebo (p < 0.05). NVA237 50 microg, 100 microg and tiotropium showed clinically relevant improvements versus placebo on Day 7 (differences of 131, 142 and 127 mL, respectively; p < 0.0001) and 1 (differences of 121, 135 and 112 mL, respectively; p < 0.0001). On Day 1, but not Day 7, FEV(1) was significantly higher (p < 0.05) with NVA237 50 and 100 microg versus tiotropium from 5 min up to 2 and 4 h post-dose, respectively. All doses of NVA237 and tiotropium were well tolerated. NVA237 once-daily was effective and well tolerated versus placebo, and demonstrated rapid and sustained 24-h bronchodilation. (ClinicalTrials.gov Identifier: NCT00501852).
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