Invasive Pneumococcal Disease Caused by Non-Vaccine Type Multidrug-Resistant Streptococcus pneumoniae Transmitted by Close Contact in a Healthy Adult

유정래,오수현,이재근,김영리,이근화,허상택 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.11

The incidence of vaccine-type Streptococcus pneumoniae carriage and disease have declined in vaccinated children as well as in unvaccinatedchildren and adults. However, diseases caused by non-vaccine type (NVT) S. pneumoniae are increasing. In this study,we report an invasive pneumococcal disease (IPD) caused by NVT multidrug-resistant (MDR) S. pneumoniae transmitted from avaccinated infant to an unvaccinated healthy woman, and the clinical characteristics of this serotype. A 29-year-old previouslyhealthy woman visited our hospital with fever and headache. She had been breastfeeding her baby for 8 months. She was diagnosedwith brain abscess and sinusitis caused by S. pneumoniae. Although the patient had no previous exposure to antibiotics, antibioticsusceptibility test identified the pathogen as MDR. The patient’s family members were examined using nasopharyngeal swabs forbacterial culture. The serotype of S. pneumoniae identified from the blood, abscess, and sputum of the patient was 15B/C. After investingthe patient’s family members, we found that the serotype from nasopharyngeal specimen of her baby was the same. We describedan invasive MDR pneumococcal disease in an immunocompetent young adult in the community. IPD likely spread to thepatient by close contact with her baby, who harbored S. pneumoniae of NVT. The spread of NVT S. pneumoniae in the post-vaccineera has increased in the community, and resistance pattern for S. pneumoniae of 15B/C changed compared to the pre-pneumococcalconjugate vaccine era. The spread of MDR pathogens causing IPD among family members should be monitored.

광디스크 드라이브를 위한 대물렌즈의 중립위치 보정

유정래 서울産業大學校 2005 논문집 Vol.54 No.3

Optical axis misalignment, which represents the position deviation of the objective lens from the optical axis, is an inevitable assembly error in an optical pick-up. Since the laser power intensity varies with respect to the distance from the optical axis, the misalignment leads to variation of the laser spot power intensity, which is one of the critical factors increasing data bit-error-rate in optical disc drives. In this paper, an auto-adjustment scheme for optical axis alignment is proposed to eliminate the undesirable variation of the laser spot power intensity in optical disc drives. An envelope of the data signal is extracted and utilized to detect the optical axis misalignment. Then an adjustment input is added to the driving input of the tracking actuator to shift the objective lens to the optical axis. Finally, the feasibility is verified by a series of experiments.

광디스크 드라이브 트랙 추종 제어 시스템을 위한 외란 관측기의 QFT 설계

유정래 서울産業大學校 2005 논문집 Vol.54 No.3

In For track-following control in optical disk drive, a compensator should be designed to satisfy disturbance attenuation property, overall system stability, and so on. In order to ease the compensator design procedure by reducing trial and errors, a disturbance observer is added on to a conventional single loop track-following control system, which may cause control input saturation due to excessive loop gain. Because the track-following control system is conditionally stable, control input saturation leads to actual reduction of loop gain whereby the system becomes unstable. To preserve the overall stability during transient response, where control input saturation possibly occurs, the circle criterion based on the pull-in condition is utilized to check the stability under control input saturation. The constraints from the circle criterion and robust stability condition are converted into frequency domain bounds, which are represented on a Nichols chart. Then a design method using quantitative feedback theory (QFT) is applied to satisfy the constraints shown on the Nichols chart. To show the feasibility, some experiments are conducted, and the results are presented.

Changes in Serotype of Streptococcus pneumoniae After the Introduction of the 13-Valent Pneumococcal Vaccine in a Homogenous Population on Jeju Island

유정래,허상택,오현주,오수현,김영리,이근화 대한감염학회 2019 Infection and Chemotherapy Vol.51 No.1

We compared the serotypes of Streptococcus pneumoniae between the pre-pneumococcal conjugate vaccine (PCV)13 era and post-PCV13 era among homogenous inhabitants of an isolated South Korean island. A total of 325 S. pneumoniae strains were isolated. In the pre-PCV13 era, 19A/F, 15A/F, 19B, and 23A serotypes were identified. In the post-PCV13 era, 15 serotypes were identified. The 19F and 23A serotypes showed the highest prevalence in the pre- and post-PCV13 era, respectively. After PCV13 introduction, the PCV 13 serotype coverage rate was decreased (80.0% and 30.5% in the pre- and post-PCV13 eras, respectively), while the proportion of non-PCV 13 serotypes increased.

On-Line Trajectory Generation for an Active Head-Eye System

유정래 서울産業大學校 2005 논문집 Vol.54 No.3

In robotic research field, vision system is one of the most powerful sensing devices. Recently, active vision system has been spotlighted, because it can solve some problems that exist in conventional passive vision systems. In order to utilize the advantages, active head-eye systems have been constructed. In this paper, an on-line trajectory generation method is presented. Basically, it adopts the weighted least norm method that was proposed in the redundant joint manipulator field. The weighting matrix is chosen in consideration of maximum joint angular velocities. For proof of feasibility, the method is applied to an active head-eye system and the result is presented.

코로나바이러스감염증-19의 임상적 특징

유정래,허상택,Yoo, Jung Rae,Heo, Sang Taek 제주대학교 의과학연구소 2020 The Journal of Medicine and Life Science Vol.17 No.2

Coronavirus disease 2019 (COVID-19) is a respiratory tract infection caused by a newly emergent coronavirus, that was first recognized in Wuhan, China, in December 2019. Genetic sequencing of the virus suggests that it is a beta coronavirus closely linked to the SARS virus. This disease has non-specific symptoms such as fever, dry cough, sore throat, and gastrointestinal symptoms. This virus can transmit via aerosol and need to droplet precaution to prevent spreading in public areas. Most people with COVID-19 develop only mild or uncomplicated illness. However, about 20% patients require hospitalization, oxygen supply, and intensive care. There is no currently effective treatment available for COVID-19 unresponsive to supportive care. This is review about the recently published epidemiologic, and clinical features, diagnosis, treatment and prevention of COVID-19.

Seroprevalence of Severe Fever with Thrombocytopenia Syndrome in the Agricultural Population of Jeju Island, Korea, 2015–2017

유정래,허상택,김미연,송성욱,부지환,이근화 대한감염학회 2019 Infection and Chemotherapy Vol.51 No.4

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne zoonotic disease that is caused by the SFTS virus (SFTSV), and exhibits an overall mortality rate of approximately 20.0% in Korea. Most cases of this disease have been reported in Korea, East China, and Japan, and it mostly affects outdoor workers and farmers. This study aimed to investigate the seroprevalence of SFTSV among healthy farmers on Jeju Island, Korea. Materials and Methods: In this prospective cross-sectional study, we analyzed 421 blood samples obtained from 254 farmers (mean age, 59.9 years; 68.9% male) to determine the seroprevalence of SFTSV in 16 rural areas of the Jeju Special Self-Governing Province over a period of 3 years (January 2015–December 2017). We used an enzyme-linked immunosorbent assay to detect immunoglobulin (Ig) G antibodies against SFTSV in the collected samples. Results: The seroprevalence of the SFTSV IgG among farmers on Jeju Island was observed to be 2.4%. One subject showed seropositivity over the entire 3-year study period. The areas with the highest SFTSV IgG seropositivity rates were Seonheul-ri in Jocheon-eup, followed by Namwon-eup. Fruit farmers were at a higher risk of exposure to SFTSV than other farmers. Conclusion: The seroprevalence of SFTSV in the healthy agricultural population of Jeju Island was not high. However, personal hygiene management should be implemented for the agricultural population in the endemic areas. Surveillance of mild or asymptomatic infections is required in the endemic regions.

고배속 광 디스크 드라이브의 고속 직접 검색 제어

유정래,정명진 대한전자공학회 1998 대한전자공학회 학술대회 Vol.1998 No.01

고배속 광 디스크 드라이브의 고속 직접 검색 제어

유정래,정명진 제어로봇시스템학회 1998 제어로봇시스템학회 합동학술대회 논문집 Vol.1998 No.3

자기공명영상에서 척추주위 농양으로 오인된 감염성 대동맥류: 증례 보고

유정래,고성주,허상택,김진석,김승형 대한영상의학회 2013 대한영상의학회지 Vol.69 No.3

The differential diagnosis of mass-like lesions around the aorta includes saccular pseudoaneurysms and abscesses. A 69-year-old female was admitted with multiple abscesses and fluid collections in several muscles and joints. Methicillin susceptible Staphylococcus aureus was isolated from her blood and pus. Even though she was treated with repeated operations and appropriate antibiotics, her conditions worsened with persistent fever and newly developed abscesses at other sites. Serial enhanced computed tomography (CT) revealed a newly developed saccular abdominal aortic aneurysm in the retroaortic space at the celiac axis level. However, the infected aortic aneurysm mimicked a prevertebral abscess on enhanced spinal magnetic resonance imaging (MRI) due to its heterogeneous signal intensity caused by intraaneurysmal turbulent blood flow. We report to alert the pitfall in the diagnosis of saccular aortic aneurysm using spinal MRI and the importance of serial enhanced CT study in highly suspicious patients. 감염성 대동맥류는 환자의 예후에 조기 진단이 중요하다. 하지만, 초기에 영상의학적으로 진단이 되지 않는 경우 진단이 늦어져 사망에 이를 수 있다. 본 증례는 전신 다발성 농양으로 입원한 환자의 초기 전산화단층촬영에서는 없었던 감염성 대동맥류가 4주 후 추적 영상검사에서 새로 생긴 것으로 진단이 되었던 경우이다. 또한 조영증강 척추 자기공명영상 검사에서 감염성 대동맥류가 내부의 난류에 의한 신호소실로 인해 조영증강이 잘 되지 않아 대동맥 주변 농양으로 오인될 수 있었던 환자로 전신 다발성 농양 환자에서 감염성 대동맥류를 진단할 때 조영증강 전산화단층촬영을 신중하게 고려해볼 필요가 있음을 보여주는 예가 되겠다.