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Kyu Sung Kim

Publications and source records attributed to Kyu Sung Kim.

2 recordsLinked to original sources

Clinical characteristics of benign paroxysmal positional vertigo in Korea: a multicenter study.

Benign paroxysmal positional vertigo (BPPV) is characterized by episodic vertigo and nystagmus provoked by head motions. To study the characteristics of BPPV in a large group of patients in Korea, we retrospectively analyzed clinical features of 1,692 patients (women: 1,146, 67.7%; men: 54.6, 32.3%; mean age: 54.8+/-14.0 yr), who had been diagnosed as BPPV by trained neuro-otologists Dizziness Clinics. The diagnosis of BPPV was based on typical nystagmus elicited by positioning maneuvers. Posterior semicircular canal was involved in 60.9% of the patients, horizontal canal in 31.9%, anterior canal in 2.2%, and mixed canals in 5.0%. The horizontal canal type of BPPV (HC-BPPV) comprised 49.5% of geotropic and 50.5% of apogeotropic types. We could observe significant negative correlation between the proportion of HC-BPPV of each clinic and the mean time interval between the symptom onset and the first visit to the clinics (r=-0.841, p<0.05). Most patients were successfully treated with canalith repositioning maneuvers (86.9%). The high incidence of HC-BPPV in this study may be explained by relatively shorter time interval between the symptom onset and visit to the Dizziness Clinics in Korea, compared with previous studies in other countries.

Aged↗

Magnetic force-based multiplexed immunoassay using superparamagnetic nanoparticles in microfluidic channel.

This paper describes a novel microfluidic immunoassay utilizing binding of superparamagnetic nanoparticles to beads and deflection of these beads in a magnetic field as the signal for measuring the presence of analyte. The superparamagnetic 50 nm nanoparticles and fluorescent 1 microm polystyrene beads are immobilized with specific antibodies. When target analytes react with the polystyrene beads and superparamagnetic nanoparticles simultaneously, the superparamagnetic nanoparticles can be attached onto the microbeads by the antigen-antibody complex. In the poly(dimethylsiloxane)(PDMS) microfluidic channel, only the microbeads conjugated with superparamagnetic nanoparticles by analytes consequently move to the high gradient magnetic fields under the specific applied magnetic field. In this study, the magnetic force-based microfluidic immunoassay is successfully applied to detect the rabbit IgG and mouse IgG as model analytes. The lowest concentration of rabbit IgG and mouse IgG measured over the background is 244 pg mL(-1) and 15.6 ng mL(-1), respectively. The velocities of microbeads conjugated with superparamagnetic nanoparticles are demonstrated by magnetic field gradients in microfluidic channels and compared with the calculated magnetic field gradients. Moreover, dual analyte detection in a single reaction is also performed by the fluorescent encoded microbeads in the microfluidic device. Detection range and lower detection limit can be controlled by the microbeads concentration and the higher magnetic field gradient.

Animals↗