Young Noh

Microwave dielectric relaxation of the polycrystalline (Ba,Sr)TiO3 thin films

The microwave dielectric properties of the (Ba,Sr)TiO3 thin films annealed at various oxygen pressures ranging from 5to500mTorr were investigated over the frequency range 0.5–5GHz using a circular-patch capacitor geometry. The dielectric constant (e) followed Curie–von Schweidler relaxation in the microwave-frequency range, and the degree of relaxation corresponded qualitatively with the measured dielectric loss (tanδ). As the oxygen pressure varied, the dielectric loss had a maximum value of ∼0.03 at 100mTorr, and its behavior was correlated with the Raman strength of the polar modes.

Distinct amyloid distribution patterns in amyloid positive subcortical vascular cognitive impairment

Amyloid-β (Aβ) and cerebral small vessel disease (CSVD) commonly coexist. They can occur independently by chance, or may interact with each other. We aimed to determine whether the distribution of Aβ in subcortical vascular cognitive impairments (SVCI) patients can be classified by the underlying pathobiologies. A total of 45 11C-Pittsburgh compound B PET positive (PiB(+)) SVCI patients were included in this study. They were classified using a new cluster analysis method which adopted the Louvain method, which finds optimal decomposition of the participants based on similarity of relative Aβ deposition pattern. We measured atherosclerotic cerebral small vessel disease (CSVD) markers and cerebral amyloid angiopathy (CAA) markers. Forty-five PiB(+) SVCI patients were classified into two groups: 17 patients with the characteristic Alzheimer’s disease like Aβ uptake with sparing of occipital region (OccSp) and 28 patients with occipital predominant Aβ uptake (OccP). Compared to OccSp group, OccP group had more postive association of atherosclerotic CSVD score (p for interaction = 0.044), but not CAA score with occipital/global ratio of PiB uptake. Our findings suggested that Aβ positive SVCI patients might consist of heterogeneous groups with combined CSVD and Aβ resulting from various pathobiologies. Furthermore, atherosclerotic CSVD might explain increased occipital Aβ uptakes.

A NOMOGRAM FOR PREDICTING AMYLOID PET POSITIVITY IN AMNESTIC MILD COGNITIVE IMPAIRMENT

load (participants with positive versus negative brain amyloid load) will be determined. Results:Hyperspectral retinal imaging will be completed for the remaining n1⁄440 participants, aged 60 years and above. Data will be analysed via image processing and preliminary findings presented at the conference. Conclusions:Successful validation of hyperspectral retinal imaging will serve as an early, non-invasive and economical diagnostic tool for preclinical AD.

IMPROVEMENTS IN BRAIN CONNECTIVITY IN PATIENTS WITH COGNITIVE IMPAIRMENTS AFTER SMARTPHONE-BASED COGNITIVE TRAINING: A PRELIMINARY STUDY

GDS: Geriatric Depression Scale, CDR: Clinical Dementia Rating, CDR SOB: Clinical Dementia Rating Sum of Box, K-IADL: Korean version of Instrumental Activities of Daily Livint, K-MMSE: Korean version of Mini-Mental State Examination,M:Male, F: Female, AD: Alzheimer’s Disease, MCI: Mild Cognitive Impairment, SD: Standard Deviation K-MMSE, Korean version of the Mini-Mental Status Examination; RLA, Rancho Los Amigos; GSI, Global synchronization index; tDCS 10, 10 days after Transcranial direct current stimulation; tDCS 20, 20 days after Trancranial direct current stimulation

IN VIVO TAU PET IMAGING IN EARLY-ONSET ALZHEIMER’S DISEASE AND LATE-ONSET ALZHEIMER’S DISEASE

and late stage aMCI showed higher rate of conversion to dementia. In this study, we investigated the tau uptakes, measured by THK 5351 PET, in early stage and late stage aMCI. We hypothesized that late stage aMCI might have more tau burdens than early stage aMCI. Methods: We prospectively recruited 34 normal controls, eight early stage aMCI, and 48 late stage aMCI from Asan and Samsung medical centers. The presence of amyloid-ß was assessed by F-florbetaben PET. Using cerebellar gray matter as a reference region, we measured mean THK 5351 SUVR in the regions that approximates the anatomical definitions of the Braak stages. Results: Frequency of amyloid positivity was 1/34 (3%), 3/8 (37.5%), and 28/48 (58.3%) in NC, early stage aMCI, and late stage aMCI, respectively. Multiple linear regression showed that compared to NC, late stage aMCI, but not early stage aMCI had more THK5351 uptakes in Braak I&II, III&IVand V&VI ROIs. However, after adding amyloid positivity to a previous model, the statistical significance disappeared. Conclusions: Our findings suggested that late stage aMCI showed increased THK5351 uptakes in entire cortex compared to NC, which might be driven by amyloid positivity.

INTERACTIVE INFLUENCE OF DEPRESSION AND APOE-E4 ALLELE ON THE DEFAULT MODE NETWORK IN SUBJECTIVE COGNITIVE IMPAIRMENT

P4-180 INTERACTIVE INFLUENCE OF DEPRESSION AND APOE-E4 ALLELE ON THE DEFAULT MODE NETWORK IN SUBJECTIVE COGNITIVE IMPAIRMENT Byung Hwa Lee, Kyung Soo Do, Jung-Hyun Kim, Jungho Cha, Young Noh, Juhee Chin, Sang Won Seo, Duk L. Na, Samsung Medical Center, Seoul, Republic of South Korea; Sungkyunkwan University, Seoul, Republic of South Korea; Hanyang University, Seoul, Republic of South Korea; Gachon University Gil Medical Center, Incheon, Republic of South Korea; Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of South Korea. Contact e-mail: byuryhan@ hanmail.net

IN VIVO TAU DEPOSITION REFLECTS NEUROPSYCHIATRIC SYMPTOMS IN COGNITIVELY IMPAIRED PATIENTS

Methods:A convenience sample of 88 AD patients was graduated in very mild to mild to moderate severity using the clinical dementia rating (CDR) (CDR 0,5, n1⁄421); (CDR 1 1⁄444 & CDR 2 n1⁄4 23). They were assessed with measures of global cognition, executive functions, episodic memory; NPS, apathy, depression and functionality (technology-activities of daily living questionnaire (T-ADLQ)). Lineal regression models were done to assess the better predictors for functional impairment in the global group and in the mild and moderate severity patients separately. Results:Functional impairment was 35618 % in the total sample, increasing it proportion according to disease severity (CDR 0,5&11⁄429% CDR2&31⁄446%). At least one behavioral symptom was present in 87% of AD patients, depressive symptoms were present in about half of the patients. Apathy (defined as AES-i >41) was present in 44 % of AD patients. Significant predictors of global functional impairment were education, NPS, global cognition and apathy; in mild AD patient’s apathy was the best predictor. Conclusions:Apathy alone explained one third of functional impairment in AD patients, been especially important in the mild severity group, it was even more relevant than measures of episodic memory, executive functions or depression. These results remark the importance of apathy evaluation to fully understand AD patient’s behavior. Funded by FONDECYT 1140423, REDES 150134, Proyecto Anillo ACT1403.

RELATIONSHIP AMONG TAU, AMYLOID BURDEN AND BRAIN ATROPHY IN EARLY-ONSET ALZHEIMER'S DISEASE AND LATE-ONSET ALZHEIMER'S DISEASE

Deposition of tau in gray matter (GM) is associated with atrophy and cognitive impairment. However, the relationship between tau accumulation and white matter integrity has not been well characterized. We sought to correlate b-amyloid and tau deposition in predefined regions of interest (ROIs) with corresponding white matter (WM) projections from these ROIs. Methods: Sixty-nine participants underwent DTI, b-amyloid (florbetapir) and tau ([18F]AV-1451 (T807, flortaucipir)) positron emission tomography imaging. Twenty-one were b-amyloid positive, including 8 persons who were CDR>0. DTI metrics were processed in FMRIB software library, and GM regions were obtained with Freesurfer 5.3. Two sets of four AD-defined regions were evaluated based on either b-amyloid (Table 1) or tau (Table 2) accumulation. Probabilistic tractography projections were created for these predefined ROIs using ten cognitively normal individuals from the Human Connectome Project (Figure 1). The projections were applied to each participant’s diffusion maps and average values calculated. Values were adjusted by age for partial correlations with either regional tau or b-amyloid. Correction for multiple comparisons was performed with false discovery rate correction (FDR). Results: Within b-amyloid defied regions, no association was seen between b-amyloid and diffusion metrics after FDR correction. With tau defined ROIs, Diffusion values within the occipital and temporal projections were associated with tau in b-amyloid positive individuals (Table 1). For the tau defined regions, b-amyloid did not associate with any diffusion metric. Significant associations were seen in all tau-defined regions for tau and absolute diffusion metrics in b-amyloid positive individuals (Table 2). No relationship was present between tau and diffusion metrics in the b-amyloid negative subjects.Conclusions:Tau and not b-amyloid accumulation was associated with changes in WM integrity. Observed changes were primarily seen in occipital and temporal projections. These results suggest that tau mediated changes primarily occur within posterior or temporal regions of the brain and are mediated by the presence of b-amyloid. IC-01-03 RELATIONSHIP AMONG TAU, AMYLOID BURDENAND BRAIN ATROPHY IN EARLYONSETALZHEIMER’S DISEASE AND LATE-ONSETALZHEIMER’S DISEASE Young Noh, Han Kyu Na, Seongho Seo, Sang-Yoon Lee, Hye Jin Jeong, Nobuyuki Okamura, Tatsuo Ido, Duk L. Na, Gachon University Gil Medical Center, Incheon, Republic of South Korea; Yonsei University, College of Medicine, Seoul, Republic of South Korea; College of Medicine, Gachon University, Incheon, Republic of South Korea; College of Medicine, Gachon University, Incheon, Republic of South Korea; Neuroscience Research Institute, Gachon University, Incheon, Republic of South Korea; Tohoku University School of Medicine, Sendai City, Japan; Tohoku Medical and Pharmaceutical University, Sendai, Japan; Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of South Korea. Contact e-mail: nymed77@ gmail.com

PO5.22 Polyneuropathy Associated with Copper Deficiency after Long-Term Parenteral Nutrition

motor weakness (Medical Research Council [MRC] grade 2) in the distal lower extremities with hypesthesia for all sensory modalities. Deep tendon reflexes were absent. Cerebrospinal fluid study showed increased protein level without cellular component. Nerve conduction studies revealed multiple conduction blocks, prolonged distal latencies, and significant slowing of conduction velocities, suggesting demyelinating type of sensorimotor polyneuropathy. Other laboratory findings including vasculitis, paraneoplastic antibodies were all negative. On lumbar spine MRI, irregular hypertrophy of nerve roots with gadolinium enhancement were seen in the lumbar regions including cauda equina, mimicking neurofibroma or schwannoma. Her neurological deficits were improved with steroid treatment. Conclusions: This is the first report of CIDP with massive nerve root hypertrophy in Korea. Hypertrophy of the spinal nerve roots may be seen on MRI, particularly in cases of CIDP of long duration, and it can be an additional clue to the diagnosis of CIDP.