Publications by authors named "Da Hee Jung"

Non-invasive transcranial direct current stimulation (tDCS), a promising stimulation tool to modulate a wide range of brain disorders, has major limitations, such as poor cortical stimulation intensity and focality. We designed a novel electrode for tDCS by conjugating a needle to a conventional ring-based high-definition (HD) electrode to enhance cortical stimulation efficacy. HD-tDCS (43 µA/mm, charge density 51.

View Article and Find Full Text PDF

Since the industrial revolution, which was accompanied with the use of fossil fuels as an energy source, the content of carbon dioxide (CO) in the atmosphere has increased. To mitigate global warming, industries that utilize fossil fuels have continuously explored new approaches to reduce CO emissions and convert it to alternative fuels. The ocean is a vast source of absorbed CO on Earth, and various studies have been conducted on the use of the ocean to reduce global CO.

View Article and Find Full Text PDF
Article Synopsis
  • * Spontaneously hypertensive rats (a genetic model for ADHD) showed increased ADHD symptoms when exposed to stress during their juvenile period, with notable differences in behavior between male and female rats.
  • * There were significant changes in dopamine-related genes and proteins, particularly in males, and stressed males responded better to treatment with methylphenidate, indicating potential for gender-specific ADHD diagnostics and treatments.
View Article and Find Full Text PDF

Background: Therapeutic effects of transcranial alternating current stimulation (tACS) for treating Parkinson's disease (PD) are limited to modulating abnormally synchronized oscillations; however, long-lasting tACS effects may involve non-neuronal mechanisms like the regulation of neurotrophic factors.

Objectives/hypothesis: We investigated whether tACS exerts neuroprotective effects on dopaminergic neurons in a mouse model of PD by regulating endogenous glial cell line-derived neurotrophic factor (GDNF).

Methods: Repeated high-definition tACS (HD-tACS, 20 min, 89.

View Article and Find Full Text PDF

Neural/glial antigen 2 (NG2)-expressing cells has multipotent stem cell activity under cerebral ischemia. Our study examined the effects of electroacupuncture (EA) therapy (2 Hz, 1 or 3 mA, 20 minutes) at the Sishencong acupoint on motor function after ischemic insult in the brain by investigating the rehabilitative potential of NG2-derived cells in a mouse model of ischemic stroke. EA stimulation alleviated motor deficits caused by ischemic stroke, and 1 mA EA stimulation was more efficacious than 3 mA EA stimulation or positive control treatment with edaravone, a free radical scavenger.

View Article and Find Full Text PDF

Objectives: Rapid detection of carbapenemase-producing Enterobacterales (CPE) is important to control spread of the resistance. We previously reported that imipenem disks prepared from injectable imipenem-cilastatin could rapidly detect KPC- and NDM-type carbapenemases. In the present study, we evaluated performance of disks of IPM and combined disks of imipenem-tazobactam and imipenem-EDTA, which were prepared from powders of imipenem and inhibitors.

View Article and Find Full Text PDF
Article Synopsis
  • Electroacupuncture (EA) therapy, using alternating current stimulation on the scalp, is explored for treating brain injuries, specifically focusing on perinatal hypoxia-ischemia (HI) in newborns.
  • A neonatal HI rat model was created by permanently ligating the left carotid artery in 7-day-old pups, followed by EA treatment at various intensities for two weeks.
  • Results showed that EA significantly improved motor and memory function, particularly with a 3 mA dosage, which also increased the thickness of the corpus callosum and the number of new neurons and astrocytes, highlighting its potential for promoting neural recovery.
View Article and Find Full Text PDF
Article Synopsis
  • Most treatments for ADHD have concentrated on adjusting the dopamine system with neurotrophic factors, and this study explores the potential of transcranial direct current stimulation (tDCS) to aid cognitive recovery in ADHD patients.
  • The research involved applying high-definition tDCS to the prefrontal cortex of male spontaneously hypertensive rats, leading to improved cognitive function and changes in specific neurotransmitter levels.
  • Findings indicate that HD-tDCS enhances neurotrophic factors, especially BDNF, and promotes neurogenesis in the hippocampus, suggesting it could be a helpful addition to current ADHD therapies.
View Article and Find Full Text PDF

Background And Purpose: The therapeutic use of transcranial direct current stimulation (tDCS), an adjuvant tool for stroke, induces long-term changes in cortical excitability, for example, the secretion of activity-dependent growth factors. We assessed the proper therapeutic configuration of high-definition tDCS (HD-tDCS) in the subacute stage of ischemic stroke and its underlying expression profiling of growth factors to propose a new method for ensuring better therapeutic effects.

Methods: Male C57BL/6J mice were subjected to middle cerebral artery occlusion, after which repetitive HD-tDCS (20 minutes, 55 µA/mm, charge density 66 000 C/m) was applied from subacute phases of their ischemic insult.

View Article and Find Full Text PDF

Purpose: A new theranostic nanomedicine involving anticancer-active cisplatin moiety was designed to study its tumor-targeting properties as well as its drug efficacy and toxicity.

Methods: A cisplatin carrier polymer was prepared by grafting equimolar polyethylene glycol of a molecular weight of 550 (PEG550) and aminoethanol to the poly(dichlorophosphazene) backbone. Cisplatin was conjugated to the carrier polymer using -aconitic acid as a linker.

View Article and Find Full Text PDF
Article Synopsis
  • Parkinson's disease involves the loss of dopaminergic neurons in the substantia nigra, but electroacupuncture (EA) may help protect these neurons by increasing levels of important neurotrophic factors.
  • In mouse models of PD, EA treatment led to improved motor skills and reduced neuron loss, similar to the effects seen with the medication levodopa.
  • EA was found to boost the expression of brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) in brain regions related to motor function, suggesting it could be a valuable therapy alongside traditional treatments for PD.
View Article and Find Full Text PDF

Background: Some traditional Oriental herbal medicines, such as Acorus tatarinowii and Acorus gramineus, produce beneficial effects for cognition enhancement. An active compound in rhizomes and the bark of these plants is α-asarone.

Purpose: This study investigated the effects of α-asarone on the proliferation and differentiation of neural progenitor cells (NPCs) in a primary culture and a murine model of ischemic stroke.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the effects of mesenchymal stem cells (MSCs) and electroacupuncture (EA) on neurogenesis in mice with brain injury.
  • When combined, mBMSC transplantation and EA treatment significantly improved motor function and reduced damage in the brain's striatum.
  • The combined therapy increased the expression of important neurotrophic factors like mature brain-derived neurotrophic factor (mBDNF) and neurotrophin-4 (NT4), suggesting that this approach enhances brain cell regeneration more effectively than either treatment alone.
View Article and Find Full Text PDF

We investigated whether electroacupuncture (EA) and treadmill (TM) exercise improve behaviors related to motor and memory dysfunction in a cerebral palsy-like rat model via activation of oligodendrogenesis. A neonatal hypoxia-ischemia model was created using Sprague-Dawley rats (P7), and these underwent EA stimulation and treadmill training from 3 to 5weeks after hypoxia-ischemia induction. EA treatment was delivered via electrical stimulation (2Hz, 1mA) at two acupoints, Baihui (GV20) and Zusanli (ST36).

View Article and Find Full Text PDF

Anisotropic graphene domains are of significant interest since the electronic properties of pristine graphene strongly depend on its size, shape, and edge structures. In this work, considering that the growth of graphene domains is governable by the dynamics of the graphene-substrate interface during growth, we investigated the shape and defects of graphene domains grown on copper lattices with different indices by chemical vapor deposition of methane at either low pressure or atmospheric pressure. Computational modeling identified that the crystallographic orientation of copper strongly influences the shape of the graphene at low pressure, yet does not play a critical role at atmospheric pressure.

View Article and Find Full Text PDF

Graphene has attracted great attention owing to its unique structural and electrical properties. Among various synthetic approaches of the graphene, metal assisted chemical vapor deposition (CVD) is the most reasonable and proper method to produce large-scale and low-defect graphene films. Until now, CVD from gaseous hydrocarbon sources has shown great promises for large-scale graphene growth, but high growth temperature is required for such growth.

View Article and Find Full Text PDF

In this work, we report that high-density, vertically grown silicon nanowires (vg-SiNWs) direct a new in vitro developmental pathway of primary hippocampal neurons. Neurons on vg-SiNWs formed a single, extremely elongated major neurite earlier than minor neurites, which led to accelerated polarization. Additionally, the development of lamellipodia, which generally occurs on 2D culture coverslips, was absent on vg-SiNWs.

View Article and Find Full Text PDF

Background And Purpose: Hepatitis C virus (HCV) infection is responsible for various chronic inflammatory liver diseases. Here, we have identified a naturally occurring compound with anti-HCV activity and have elucidated its mode of antiviral action.

Experimental Approach: Luciferase reporter and real-time RT-PCR assays were used to measure HCV replication.

View Article and Find Full Text PDF

We report that graphene flakes and films which were synthesized by copper-catalyzed atmospheric pressure chemical vapor deposition (APCVD) method using a mixture of Ar, H2, and CH4 gases. It was found that variations in the reaction parameters, such as reaction temperature, annealing time, and growth time, influenced the domain size of as-grown graphene. Besides, the reaction parameters influenced the number of layers, degree of defects and uniformity of the graphene films.

View Article and Find Full Text PDF

We report an approach for the synthesis of mono- or bilayer graphene films by atmospheric-pressure chemical vapor deposition that can achieve a low defect density through control over the growth time. Different heating ramp rates were found to lead to variation in the smoothness and grain size of the Cu foil substrate, which directly influenced the density of the graphene domains. The rough Cu surface induced by rapid heating creates a high density of graphene domains in the initial stage, ultimately resulting in a graphene film with a high defect density due to an increased overlap between domains.

View Article and Find Full Text PDF

The epitaxial growth of 1D nanostructures is of particular interest for future nanoelectronic devices such as vertical field-effect transistors because it directly influences transistor densities and 3D logic or memory architectures. Silicon nanowires (SiNWs) are a particularly important 1D nanomaterial because they possess excellent electronic and optical properties. What is more, the scalable fabrication of vertically aligned SiNW arrays presents an opportunity for improved device applications if suitable properties can be achieved through controlling the alignment and density of SiNWs, yet this is something that has not been reported in the case of SiNWs synthesized from Au films.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_session78ev005lum2ao36a4albvuvjdrq1r90q): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once