Publications by authors named "Hyunseob Lee"

Background: Whether telomere length (TL), an indicator of biological ageing, reflects Alzheimer's disease (AD)-related neuropathological change remains unclear. We investigated the relationships between TL, in vivo AD pathologies, including cerebral beta-amyloid and tau deposition, and cognitive outcomes in older adults.

Methods: A total of 458 older adults were included, encompassing both cognitively normal (CN) individuals and those cognitively impaired (CI), with the CI group consisting of individuals with mild cognitive impairment or AD dementia.

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This study aims to demonstrate that when performing dynamic time warping (DTW) on gait data, multiple optimal warping paths (OWPs) with a minimum sum of local costs can occur and to propose an additional OWP selection method to address this problem. A 3-dimensional motion analysis experiment was conducted on 55 adult participants, including both males and females, to acquire gait data. This study analyzed 990 instances of DTW on gait data to examine the occurrence of multiple OWPs with the minimum sum of local costs.

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The purpose of this study was to verify classification performance and the difference analysis between gender using optimal warping paths of dynamic time warping (DTW) and to examine the usefulness of root mean square error (RMSE) represented by the perpendicular distance from the optimal warping path to the diagonal. A 3-dimensional motion analysis experiment was performed with 24 healthy adults (male=12, female=12) in their 20s of age without gait-related diseases or injuries for the past 6 months to collect gait data. This study performed a DTW 132 times in total (male=62, female=62) for the flexion angle of the right leg's hip, knee, and ankle joints.

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Purpose: The purpose of this pilot study was to determine whether physiological tremors (PTs) assessed using an accelerometer could be used to evaluate resistance exercise intensity.

Methods: Twenty healthy young men with no prior experience of resistance exercise were recruited. Different intensities (resting, 30%, 50%, and 70% of their predetermined one-repetition maximum (1-RM)) of arm-curl exercise were used to elicit PT.

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Background: Participation in exercise, and dietary and nutritional intakes have an impact on the risk and prevalence of metabolic syndrome (MetS), but these effects may differ according to whether a person lives alone or in a multi-person household. We analyzed differences in physical activity (PA) levels and energy intake according to household-type and MetS presence among young adults, to investigate the relationships among these factors.

Methods: Data of 3974 young adults (aged > 19 years and < 40 years) were obtained from the Korean National Health and Nutrition Examination Survey (2016-2018).

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Successful clinical translation of stem cell-based therapy largely relies on the scalable and reproducible preparation of donor cells with potent therapeutic capacities. In this study, midbrain organoids were yielded from human pluripotent stem cells (hPSCs) to prepare cells for Parkinson's disease (PD) therapy. Neural stem/precursor cells (NSCs) isolated from midbrain organoids (Og-NSCs) expanded stably and differentiated into midbrain-type dopamine(mDA) neurons, and an unprecedentedly high proportion expressed midbrain-specific factors, with relatively low cell line and batch-to-batch variations.

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Background: To date, no genetic analysis of inherited retinal disease (IRD) using whole-exome sequencing (WES) has been conducted in a large-scale Korean cohort. The aim of this study was to characterise the genetic profile of IRD patients in Korea using WES.

Methods: We performed comprehensive molecular testing in 168 unrelated Korean IRD patients using WES.

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The purpose of this study was to comparatively analyze normal gait on the plains by gender for old people reference data for the normal gait pattern for the old people. Participants were selected according to the Korean standard body type provided by the Ministry of Health and Welfare and used a three-dimensional motion analysis system. Cortex, Orthotrak, and Excel were used as the software for analyzing the extracted data, and IBM SPSS Statistics ver.

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Many studies have shown the existence of cardiac stem cells in the myocardium and epicardial progenitor cells in the epicardium. However, the characteristics of stem cells in the endocardium has not been fully elucidated. In this study, we investigated the origin of newly identified cells in the blood and their therapeutic potential.

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Parkinson's disease (PD) is neurodegenerative movement disorder characterized by degeneration of midbrain-type dopamine (mDA) neurons in the substantia nigra (SN). The RNA-binding protein Lin28 plays a role in neuronal stem cell development and neuronal differentiation. In this study, we reveal that Lin28 conditional knockout (cKO) mice show degeneration of mDA neurons in the SN, as well as PD-related behavioral deficits.

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Autosomal dominant polycystic kidney disease (ADPKD) is one of the main causes of end-stage renal disease (ESRD). Genetic information is of the utmost importance in understanding pathogenesis of ADPKD. Therefore, this study aimed to demonstrate the genetic characteristics of ADPKD and their effects on renal function in 749 Korean ADPKD subjects from 524 unrelated families.

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Identifying the association between somatic mutations and the radiation response of tumor is essential for understanding the mechanisms and practicing personalized radiotherapy. The present study aimed to discover specific genes or pathways that are associated with radiation response using targeted next-generation DNA sequencing. Fifty-five patients with various solid tumors whose specimen were sequenced using institutional panel which includes 148 cancer-related genes and received radiotherapy for a measurable tumor were analyzed.

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The purpose of this study was to investigate the effectiveness of dynamic time warping (DTW) in gait research. Participants in this study were consist of 10 males and 10 females. Equipment used for collecting the gait data of participants in this study was three-dimensional (3D) motion analysis system consisted of 8 infrared CCD cameras operated with a sampling frequency of 120 frames/sec.

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Bilateral common carotid arteries occlusion (BCCAO) causes an abrupt reduction of cerebral blood flow, and this method has been used to investigate the effects of chronic cerebral hypoperfusion on vascular dementia and neuronal injuries. Chronic cerebral hypoperfusion leads to functional changes in the hippocampus and then results in a cognitive impairment. We investigated the effect of preischemic treadmill exercise on short-term memory and blood-brain barrier integration following cerebral hypoperfusion caused by BCCAO.

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Autosomal dominant polycystic kidney disease (ADPKD), one of the most common human monogenic diseases (frequency of 1/1000-1/400), is characterized by numerous fluid-filled renal cysts (RCs). Inactivation of the PKD1 or PKD2 gene by germline and somatic mutations is necessary for cyst formation in ADPKD. To mechanistically understand cyst formation and growth, we isolated RCs from Korean patients with ADPKD and immortalized them with human telomerase reverse transcriptase (hTERT).

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The purpose of this study was to analyze the activity of ankle muscles during normal gait by simulation method using the human musculoskeletal model. The equipment used in this study was three-dimensional motion capture system and force platform, and OpenSim was used for simulation. Collected data was scaled to Gait2392 that is the human musculoskeletal simulation model using in the OpenSim.

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For the best results in quantitative polymerase chain reaction (qPCR) experiments, it is essential to design high-quality primers considering a multitude of constraints and the purpose of experiments. The constraints include many filtering constraints, homology test on a huge number of off-target sequences, the same constraints for batch design of primers, exon spanning, and avoiding single nucleotide polymorphism (SNP) sites. The target sequences are either in database or given as FASTA sequences, and the experiment is for amplifying either each target sequence with each corresponding primer pairs designed under the same constraints or all target sequences with a single pair of primers.

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Tuberous sclerosis complex-associated renal cell carcinoma (TSC-RCC) has distinct clinical and histopathologic features and is considered a specific subtype of RCC. The genetic alterations of TSC1 or TSC2 are responsible for the development of TSC. In this study, we assessed the mTOR pathway activation and aimed to evaluate molecular characteristics and pathogenic pathways of TSC-RCC.

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Parkinson's disease (PD) is the second most common age-related neurodegenerative disease in the elderly and the patients suffer from uncontrolled movement disorders due to loss of dopaminergic (DA) neurons on substantia nigra pars compacta (SNpc). We previously reported that transplantation of human fetal midbrain-derived neural precursor cells restored the functional deficits of a 6-hydroxy dopamine (6-OHDA)-treated rodent model of PD but its low viability and ethical issues still remain to be solved. Albeit immune privilege and neural differentiation potentials suggest mesenchymal stem cells (MSCs) from various tissues including human placenta MSCs (hpMSCs) for an alternative source, our understanding of their therapeutic mechanisms is still limited.

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Transplantation of neural progenitor cells (NPCs) is a potential therapy for treating neurodegenerative disorders, but this approach has faced many challenges and limited success, primarily because of inhospitable host brain environments that interfere with enriched neuron engraftment and function. Astrocytes play neurotrophic roles in the developing and adult brain, making them potential candidates for helping with modification of hostile brain environments. In this study, we examined whether astrocytic function could be utilized to overcome the current limitations of cell-based therapies in a murine model of Parkinson's disease (PD) that is characterized by dopamine (DA) neuron degeneration in the midbrain.

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We have developed a good manufacturing practice for long-term cultivation of fetal human midbrain-derived neural progenitor cells. The generation of human dopaminergic neurons may serve as a tool of either restorative cell therapies or cellular models, particularly as a reference for phenotyping region-specific human neural stem cell lines such as human embryonic stem cells and human inducible pluripotent stem cells. We cultivated 3 different midbrain neural progenitor lines at 10, 12, and 14 weeks of gestation for more than a year and characterized them in great detail, as well as in comparison with Lund mesencephalic cells.

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Use of the physiological mechanisms promoting midbrain DA (mDA) neuron survival seems an appropriate option for developing treatments for Parkinson's disease (PD). mDA neurons are specifically marked by expression of the transcription factors Nurr1 and Foxa2. We show herein that Nurr1 and Foxa2 interact to protect mDA neurons against various toxic insults, but their expression is lost during aging and degenerative processes.

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Deciphering the molecular basis of neuronal cell death is a central issue in the etiology of neurodegenerative diseases, such as Parkinson's and Alzheimer's. Dysregulation of p53 levels has been implicated in neuronal apoptosis. The role of histone deacetylase 3 (HDAC3) in suppressing p53-dependent apoptosis has been recently emphasized; however, the molecular basis of modulation of p53 function by HDAC3 remains unclear.

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