Nosocomial Outbreak of COVID-19 from a Kidney Transplant Patient: Necessity of a Longer Isolation Period in Immunocompromised Patients

Kim Chang Seong,Kim Uh Jin,Lee Yoonjung,Lee Unhee,Choi Okja,Kim Sun-Hee,Lee Kwangho,Chung Yoon-Seok,Choi Hong Sang,Bae Eun Hui,Ma Seong Kwon,Kim Seong Eun,Kang Seung-Ji,Jung Sook-In,Kim Soo Wan,Park K 대한감염학회 2023 Infection and Chemotherapy Vol.55 No.1

Background: Determination of the release from isolation for coronavirus disease 2019 (COVID-19) in immunocompromised patients who need additional hospitalization for treatment of non-COVID-19 related disease is important to prevent nosocomial transmission. However, there is insufficient evidence for an extended isolation period. Materials and Methods: In September 2021, when the Delta variant was dominant, a nosocomial outbreak of COVID-19 occurred in the nephrology ward of a tertiary hospital in Gwangju, Korea. We conducted epidemiological investigations and whole-genome sequencing (WGS) of this virus. Results: A man who underwent kidney transplantation was admitted to our hospital for the treatment of acute kidney injury. He was diagnosed with asymptomatic COVID-19 infection during a pre-admission screening test on September 1, 2021 and underwent isolation. After 10 days of isolation in the COVID-19-designated ward, he was transferred to the general nephrology ward. He underwent steroid pulse therapy (September 17 to September 23, >60 mg/day prednisolone) due to acute T-cell rejection. On September 28, 2021, the first patient with COVID-19 was identified in the nephrology ward, and a rapid-response team was activated to identify additional patients with COVID-19 and prevent the spread of COVID-19. Epidemiological investigations revealed that 12 patients, two caregivers, and three healthcare workers from the nephrology ward were diagnosed with COVID-19. The WGS of specimens from 14 nosocomial outbreak samples and released an index patient exhibited the same Delta variant originating from the B.1.617.2 lineage. This hospital-acquired COVID-19 outbreak in the nephrology ward resulted in two (11.7%) deaths in patients who underwent kidney transplantation. Conclusion: We demonstrated that an immunocompromised patient can cause a nosocomial outbreak due to the prolonged shedding of infectious viruses. Prolonged isolation in patients under active immunosuppressive therapy may be necessary to prevent transmission, especially in the hospital setting.

Copper-Catalyzed Selective Arylations of Benzoxazoles with Aryl Iodides

Kim, Donghae,Yoo, Kwangho,Kim, Se Eun,Cho, Hee Jin,Lee, Junseong,Kim, Youngjo,Kim, Min American Chemical Society 2015 Journal of organic chemistry Vol.80 No.7

<P>A copper-catalyzed direct ring-opening double N-arylation of benzoxazoles with aryl iodides has been developed. The present system exhibits high selectivity despite competition from C-arylation. The selectivity between ring-opening N-arylation and C-arylation was controlled by the choice of reaction vessel. The nitrile bound bis(triphenylphosphine)copper cyanide was identified as the active catalytic species for both reactions, and when combined with a nitrile-containing solvent, enhanced the reaction efficiency.</P>

Epigenetic regulation of SMAD3 by histone methyltransferase SMYD2 promotes lung cancer metastasis

Kim Kwangho,Ryu Tae Young,Jung Eunsun,Han Tae-Su,Lee Jinkwon,Kim Seon-Kyu,Roh Yu Na,Lee Moo-Seung,Jung Cho-Rok,Lim Jung Hwa,Hamamoto Ryuji,Lee Hye Won,Hur Keun,Son Mi-Young,Kim Dae-Soo,Cho Hyun-Soo 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Epigenetic alterations, especially histone methylation, are key factors in cell migration and invasion in cancer metastasis. However, in lung cancer metastasis, the mechanism by which histone methylation regulates metastasis has not been fully elucidated. Here, we found that the histone methyltransferase SMYD2 is overexpressed in lung cancer and that knockdown of SMYD2 could reduce the rates of cell migration and invasion in lung cancer cell lines via direct downregulation of SMAD3 via SMYD2-mediated epigenetic regulation. Furthermore, using an in vitro epithelial-mesenchymal transition (EMT) system with a Transwell system, we generated highly invasive H1299 (In-H1299) cell lines and observed the suppression of metastatic features by SMYD2 knockdown. Finally, two types of in vivo studies revealed that the formation of metastatic tumors by shSMYD2 was significantly suppressed. Thus, we suggest that SMYD2 is a potential metastasis regulator and that the development of SMYD2-specific inhibitors may help to increase the efficacy of lung cancer treatment.

Neurogenic rosacea in Korea

( Hyeone Kim ),( Seokyoung Kang ),( Koeun Kim ),( Soyun Cho ),( Kwangho Kim ),( Il-hwan Kim ) 대한피부과학회 2020 대한피부과학회 학술발표대회집 Vol.72 No.1

Background: Rosacea with severe neurologic symptoms such as burning and stinging is often not effectively treated with conventional therapies. Objectives: The aim of this study was to investigate the clinical characteristics of Korean rosacea patients with prominent neurological symptoms. Methods: In the present study, the demographic features, medical history, clinical manifestations, and treatment modalities of 17 neurogenic rosacea patients that had prominent neurologic symptoms and 106 erythematotelangiectatic rosacea (ETR) patients are investigated as a control group. Results: All seventeen neurogenic rosacea patients had severe persistent erythema with burning/stinging sensation limited to both cheeks. Among these patients, 94.1% were female (16/17), 23.6 % had dyslipidemia (4/17), 17.7 % had hypertension (3/17), and 17.7% had psychiatric diseases. Heat stimuli (58.8 %, [10/17]), and stress (52.9 %, [9/17]) were major aggravating factors. Cold stimuli alleviated the symptoms in half of the patients (41.2 %, [7/17]). Fourteen of seventeen patients (82.3 %) improved after receiving anticonvulsants and antidepressants. Conclusion: Rosacea patients with severe neurologic symptoms show distinct clinical manifestations and should be classified separately, and a different therapeutic approach is necessary for them

지하시설물의 3D 시각화에 관한 연구

김광호(Kwangho Kim),조홍범(Hongbeom Cho),강병준(Byungjun Kang),김민석(Minsuk Kim),김인현(Inhyun Kim) 대한공간정보학회 2008 한국공간정보학회 학술대회 Vol.2008 No.6

지하시설물은 상수, 전력, 가스를 공급하고, 하수를 처리하는 동시에 정보통신망을 구축하는 중요한 도시기반시설이기 때문에 지하시설물에 관한 정보가 상당히 중요하게 대두되고 있다. 기존의 도시시설물들은 지상에 설치되어 왔으나 도시의 집중화에 따른 건설안전, 도시 미관, 유지 관리의 용이성을 위하여 시설물을 지하에 매설하는 경향이 높아짐에 따라 이러한 지하시설물의 효과적인 유지관리가 필요하게 되었다. 본 연구에서는 지하시설물 중 상ㆍ하수도 정보의 3차원 영상 가시화 기능을 개발하여 도시 지하시설물의 체계적인 관리 기술 및 안전성 확보하고자 하였다. 연구 대상으로 한 3차원 영상 가시화 항목은 현행 도시 관리 체계에서 다루고 있는 지리적 범위내의 지하시설물 중 상ㆍ하수도 시설물이다. 도시 지하시설물의 3차원 시각화를 위하여 지하시설물의 항목 별 분류를 수행하였으며 지하시설물의 3차원 시각화 적용 방안에 대한 연구를 수행하였다. 또한 지하시설물 항목별 데이터 관리 빙안을 수립하여 3차원 관리 대상 데이터를 제시하였으며 가시화 테스트를 통하여 3차원 영상 가시화 기능을 검증하였다. 본 연구에서 제시한 지하시설물의 3차원 시각화 기능은 도시 지하시설물 관리 기술의 혁신을 선도할 것으로 기대한다.

4-포트 수평/수직 겸용 프로브용 교정키트

김태호(Taeho Kim),김종현(Jonghyeon Kim),김성준(Sungjun Kim),김광호(Kwangho Kim),푸보(Bo Pu),나완수(Wansoo Nah) 한국전자파학회 2014 한국전자파학회논문지 Vol.25 No.5

본 논문에서는 4-포트 수평/수직 프로브 스테이션을 사용하여 수직 커넥터 핀의 특성 측정 시 사용되는 회로망 분석기의 교정용 키트(calibration kit)를 제안한다. 기존의 수평면에서 사용되는 교정키트를 사용하면, 교정 후 프로브 암의 변경 및 추가적인 장치가 필요하며, 이로 인한 시간 소요뿐 아니라, 주변 상황에 민감한 프로브 팁의 위치 변동에 기인한 정밀도 훼손의 위험이 있다. 본 논문에서는 이를 보완할 수 있는 4-포트 수평/수직 겸용 교정키트를 제시한다. 교정은 SOLT 방법을 이용하였으며, Short, Open, Load는 수평면에서 교정하며, Thru는 프로브의 위치에 따라서 교정기판의 같은 수평면에서 교정하거나 또는 교정기판의 위쪽, 아래쪽을 수직으로 연결하여 사용할 수 있도록 설계/제작하였다. 즉, 기판에 수직한 Thru를 교정할 때에는 교정키트를 수직으로 세워 키트 양면을 사용하여 교정할 수 있는 방법을 제안하였다. 제안한 교정키트에서의 SOLT 회로 반사/전달 특성을 기존 교정키트의 SOLT 회로의 반사/전달 특성과 비교 분석하였으며, 두 교정키트의 전달 특성은 길이 보정 후, 300 kHz부터 8.5 GHz까지 약 ±0.1 dB의 차이가 있음을 확인할 수 있었다. 이와 같이 설계/제작된 4-포트 수평/수직 교정키트의 유용성을 입증하기 위하여 각각 수평 측정의 경우와 수직 측정의 경우의 두 가지 경우 사례 연구를 수행하였으며, 그 결과를 기존의 교정키트를 사용한 후 측정된 결과 데이터와 비교 분석하였다. In this paper, we propose a horizontal/vertical calibration kit for calibrating a vector network analyzer(VNA) to measure the vertical connector pin. If the conventional calibration kit is used, we should change the arm for a probe or need an assistant device and it takes a long time. In addition there is a risk of precision degradation caused by the position change of the probe tip sensitive to the surroundings. We suggest a 4-port vertical calibration kit to make up for the aforementioned shortcomings. The calibration kit was manufactured for the SOLT calibration method. ‘Short’, ‘Open’, and ‘Load’ are available in the horizontal plane, ‘Thru’ is available not only in the horizontal plane on the two planes of a PCB, but in the vertical plane between the two planes according to the positions of the probes. We complemented the conventional calibration kit to make a vertical calibration kit to be used for the vertical measurement method. We compared and analysed their reflection/transfer characteristics of the SOLT calibration standards of the proposed calibration kit and conventional one, we get a ±0.1 dB differences of transfer characteristics in the range from 300 kHz to 8.5 GHz. In order to demonstrate usefulness, and we performed a case study for horizontal and vertical cases, and compared the results of the proposed calibration kit and conventional one.

Cold hardiness of the palm thrips, Thrips palmi

Youngjin Park,Kwangho Kim,Yonggyun Kim 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.10

Cold tolerance of the palm thrips, Thrips palmi Karny, was investigated to predict its survival in field during winter. Supercooling temperatures of T. palmi ranged from -26.4 to -18.4°C. However, exposure to subzero temperatures (from -5°C to -15°C) gave significant mortality to all developmental stages of T. palmi. Thus, T. palmi was determined to be a freeze-susceptible and suffered with cold injury. A brief pre-exposure to a low temperature (4°C) for 7 h significantly increase the cold tolerance of all stages of T. palmi with respect to survival at -10°C and supercooling capacity. A pre-exposure of T. palmi at 4°C significantly increased the survival rate on all developmental stages at -10°C. The rapid cold hardiness (RCH) was dependent on the duration of the pre-exposure period at 4°C in adult stage. Cryoprotectant analysis using an HPLC showed that the pre-exposure treatment increased the adult to synthesize glycerol, trehalose, mannitol, and mannose, at which trehalose represented the highest content. This study suggests that all stages of T. palmi are able to become cold-hardy by RCH, in which several polyols may play crucial roles as cryoprotectant.

Electrical and mechanical diagnosis of aging 600 V rated STP cables in a nuclear power plant

Kim, Kwangho,Shin, Jaeyoung,Kim, Byung-Sung,Nah, Wansoo,Lim, Chanwoo,Chai, Jangbom Institute of Electrical and Electronic Engineers 2017 IEEE transactions on dielectrics and electrical in Vol.24 No.3

<P>This paper proposes electrical and mechanical diagnostic methods to estimate the aging effects of 14 American wire gage (AWG) 600 V rated shielded twisted pair (STP) cables used in nuclear power plant. The cables were accelerated to be degraded in a dry oven using Arrhenius's equation, and the properties of healthy and degraded cables were estimated electrically and mechanically as well. S-parameters were measured using a vector network analyzer (VNA) and were used to assess the aging effects of the degraded cable. An effective modulus was also used as an aging indicator of the mechanical properties. An indenter was designed and fabricated to measure the effective modulus of aged cables. Both methods' results were compared and found to be effective for diagnosing the deterioration of the aging cables. Therefore, the proposed methods could be very useful for maintaining power cables in nuclear power plants.</P>

한국 중소제조기업의 내부마케팅요인이 고객지향성과 시장지향성 및 경영성과에 미치는 영향에 관한 연구

( Kwangho Kim ),( Hyeonsuk Park ) 국제지역학회 2014 국제지역연구 Vol.18 No.2

This study saw the employees working at administration department as the core human resource of the enterprise and has analysed effects of small and medium manufacturer’s internal marketing on customer orientation, market orientation and business performance in korea. The implications are as follows; First, reward system turned out to have more effect on the customer orientation than the delegation of authority, while training and education, and managerial support did not have similar effect. Second, internal marketing activity factors appeared to make similar effect on the market orientation in the order of reward system, managerial support, and delegation of authority, but training and education did not appear to make similar effect. Third, delegation of authority and training and education made direct effect on business performance. However, managerial support and reward system did not appear to make direct effect on business performance. Fourth, customer orientation and market orientation made direct effect on business performance.

Implications of Exonuclease Activity of Bacteriophage P2 Old Protein for Lambda Exclusion

KIM, KWANGHO,PARK, CHANHEE,YEO, HYEONJOO,KEE, YOUNGHOON,PARK, JUNGCHAN,MYUNG, HEEJOON 한국미생물 · 생명공학회 2000 Journal of microbiology and biotechnology Vol.10 No.2

Temperate bacteriophage P2 has a nonessential gene called old (overcoming lysoginization defection). In the presence of old, the growth of the host (Escherichia coli) with recBC^- genotype is inhibited, and another bacteriophage, lambda, cannot superinfect. The Old protein has been shown to possess an exonuclease activity. Three mutant P2s (old 1. old 17, old 49) which did not exhibit lambda exclusion were obtained and each old gene was cloned into expression vectors to produce hexahistidine-tagged proteins. The proteins were affinity-purified and shown to lose its exonuclease activity on both double-stranded and single-stranded DNA substrates. Thus, it was concluded that the lambda exclusion was related to Old's exonuclease activity.