Biology subjects

Cha, J.

Publications and source records attributed to Cha, J..

40 records · Page 3Linked to original sources

bioRxiv2018

Comparisons among Vestibular Examinations and Symptoms of Vertigo in Sudden Sensorineural Hearing Loss Patients

ObjectiveVertigo in sudden sensorineural hearing loss (SSNHL) is hypothesized as an extension of the disease caused by the anatomical proximity of the cochlea and vestibule. The present study aimed to demonstrate the association of vestibular function test (VFT) results with SSNHL disease severity and prognosis.\n\nSubjects and methodsThis study assessed clinical records of 263 SSNHL patients admitted to our hospital, between January 2010 and October 2017. Steroid treatment comprised high-dose intravenous dexamethasone (16 mg/d) or oral methylprednisolone (64 mg/d) for 4 days and tapered oral methylprednisolone for 8 days after discharge. Caloric tests were performed in all patients, and cervical vestibular-evoked myogenic potential (c-VEMP) and ocular VEMP (o-VEMP) tests were performed in 209 and 144 patients, respectively.\n\nResultsNinety six patients had vertigo, and caloric abnormalities were observed in 119 patients. Initial PTA in patients with vertigo were worse than in those without vertigo (63.0 dB vs 72.7 dB, P=.002). Initial PTA in patients with abnormal o-VEMP was worse than in those with normal o-VEMP (61.4 dB vs 73.0 dB, P=.004). PTA improvement after steroid treatment in patients with vertigo was lower than in those without vertigo (25.0 dB vs 20.9 dB, P=.028). PTA improvement after treatment in patients with abnormal caloric results was lower than in those with normal caloric results (26.0 dB vs 18.4 dB, P=.013).\n\nConclusionsThe functions of vestibular organs, particularly the utricle and lateral semicircular canal, are associated with disease severity and hearing outcome in SSNHL patients.

bioinformatics↗

bioRxiv2018

Diagnosis and Prognosis Using Machine Learning Trained on BrainMorphometry and White Matter Connectomes

Accurate, reliable prediction of risk for Alzheimers disease (AD) is essential for early, disease-modifying therapeutics. Multimodal MRI, such as structural and diffusion MRI, is likely to contain complementary information of neurodegenerative processes in AD. Here we tested the utility of the multimodal MRI (T1-weighted structure and diffusion MRI), combined with high-throughput brain phenotyping--morphometry and structural connectomics--and machine learning, as a diagnostic tool for AD. We used, firstly, a clinical cohort at a dementia clinic (National Health Insurance Service-Ilsan Hospital [NHIS-IH]; N=211; 110 AD, 64 mild cognitive impairment [MCI], and 37 cognitively normal with subjective memory complaints [SMC]) to test the diagnostic models; and, secondly, Alzheimers Disease Neuroimaging Initiative (ADNI)-2 to test the generalizability. Our machine learning models trained on the morphometric and connectome estimates (number of features=34,646) showed optimal classification accuracy (AD/SMC: 97% accuracy, MCI/SMC: 83% accuracy; AD/MCI: 97% accuracy) in NHIS-IH cohort, outperforming a benchmark model (FLAIR-based white matter hyperintensity volumes). In ADNI-2 data, the combined connectome and morphometry model showed similar or superior accuracies (AD/HC: 96%; MCI/HC: 70%; AD/MCI: 75% accuracy) compared with the CSF biomarker model (t-tau, p-tau, and Amyloid {beta}, and ratios). In predicting MCI to AD progression in a smaller cohort of ADNI-2 (n=60), the morphometry model showed similar performance with 69% accuracy compared with CSF biomarker model with 70% accuracy. Our comparison of classifiers trained on structural MRI, diffusion MRI, FLAIR, and CSF biomarkers show the promising utility of the white matter structural connectomes in classifying AD and MCI in addition to the widely used structural MRI-based morphometry, when combined with machine learning.\n\nHighlightsO_LIWe showed the utility of multimodal MRI, combining morphometry and white matter connectomes, to classify the diagnosis of AD and MCI using machine learning.\nC_LIO_LIIn predicting the progression from MCI to AD, the morphometry model showed the best performance.\nC_LIO_LITwo independent clinical datasets were used in this study: one for model building, the other for generalizability testing.\nC_LI

neuroscience↗

bioRxiv2018

Accurate Prediction of Alzheimer’s Disease Using Multi-Modal MRI and High-Throughput Brain Phenotyping

Accurate, reliable prediction of risk for Alzheimers disease (AD) is essential for early, disease-modifying therapeutics. Multimodal MRI, such as structural and diffusion MRI, is likely to contain complementary information of neurodegenerative processes in AD. Here we tested the utility of commonly available multimodal MRI (T1-weighted structure and diffusion MRI), combined with high-throughput brain phenotyping--morphometry and connectomics--and machine learning, as a diagnostic tool for AD. We used, firstly, a clinical cohort at a dementia clinic (study 1: Ilsan Dementia Cohort; N=211; 110 AD, 64 mild cognitive impairment [MCI], and 37 subjective memory complaints [SMC]) to test and validate the diagnostic models; and, secondly, Alzheimers Disease Neuroimaging Initiative (ADNI)-2 (study 2) to test the generalizability of the approach and the prognostic models with longitudinal follow up data. Our machine learning models trained on the morphometric and connectome estimates (number of features=34,646) showed optimal classification accuracy (AD/SMC: 97% accuracy, MCI/SMC: 83% accuracy; AD/MCI: 97% accuracy) with iterative nested cross-validation in a single-site study, outperforming the benchmark model (FLAIR-based white matter hyperintensity volumes). In a generalizability study using ADNI-2, the combined connectome and morphometry model showed similar or superior accuracies (AD/HC: 96%; MCI/HC: 70%; AD/MCI: 75% accuracy) as CSF biomarker model (t-tau, p-tau, and Amyloid {beta}, and ratios). We also predicted MCI to AD progression with 69% accuracy, compared with the 70% accuracy using CSF biomarker model. The optimal classification accuracy in a single-site dataset and the reproduced results in multi-site dataset show the feasibility of the high-throughput imaging analysis of multimodal MRI and data-driven machine learning for predictive modeling in AD.

neuroscience↗

bioRxiv2018

Risk factors associated with Parkinson’s disease: An 11-year population-based South Korean study

ObjectiveTo validate various known risk factors of Parkinsonism and to establish basic information to formulate public health policy by using a 10-year follow-up cohort model.\n\nMethodsThis population based nation-wide study was performed using the National Health Insurance Database of reimbursement claims of the Health Insurance Review and Assessment Service of South Korea data on regular health check-ups in 2003 and 2004, with 10 years follow-up.\n\nResultsWe identified 7,746 patients with Parkinsonism. Old age, hypertension, diabetes, depression, anxiety, taking statin medication, high body mass index, non-smoking, non-alcohol drinking, and low socioeconomic status were each associated with an increase in the risk of Parkinsonism (fully adjusted Cox proportional hazards model: hazard ratio (HR) 1.259, 95% confidence interval (CI) 1.194-1.328 for hypertension, HR 1.255, 95% CI 1.186-1.329 for diabetes, HR 1.554, 95% CI 1.664-1.965 for depression, HR 1.808, 95% CI 1.462-1.652 for anxiety, and HR 1.157, 95% CI 1.072-1.250 for taking statin medication).\n\nConclusionsIn our study, old age, depression, anxiety, and a non-smoker status were found to be risk factors of Parkinsonism, in agreement with previous studies. However, sex, hypertension, diabetes, taking statin medication, non-drinking of Alcohol, and lower socioeconomic status have not been described as risk factors in previous studies and need further verification in future studies.

epidemiology↗