Chromogenic In Situ Hybridization을 이용한 돼지 정자의 성 선별

김효현,노다은,조태경,변진우,이정화,김윤섭,황유진,김대영 韓國受精卵移植學會 2007 한국동물생명공학회지 Vol.22 No.3

돼지 정자의 성 선별에는 일반적으로 유속 세포 분석기를 이용한다. 유속 세포 분석은 DNA량의 차이에 기초하여 정자를 분리하는 기술로써 X 정자와 Y 정자를 90% 정확도로 분리할 수 있다. 그러나 이러한 유속 세포분석 기술은 정자의 손상을 야기해 정자의 기능과 수정능에 영향을 미치므로, 본 연구에서는 특정한 핵산 서열을 탐지할 수 있는 Chromogenic in situ hybridization(CISH)을 그와 비교하여 평가하였다. 유속 세포 분석을

Long-Term Outcomes of Preoperative Atrial Fibrillation in Cardiac Surgery

김효현,김지홍,이삭,주현철,윤영남,유경종,이승현 대한흉부외과학회 2022 Journal of Chest Surgery (J Chest Surg) Vol.55 No.5

Background: Atrial fibrillation (Afib) is a marker of increased cardiovascular morbidity and mortality. Owing to the increased prevalence of Afib in patients undergoing cardiac surgery, assessing the effect of Afib on postsurgical outcomes is important. We aimed to analyze the effect of preoperative Afib on clinical outcomes in patients undergoing cardiac surgery using a large surgical database. Methods: This retrospective cohort study was based on the national health claims database established by the National Health Insurance Service of the Republic of Korea from 2009 to 2015. Diagnosis and procedure codes were used to identify diseases according to the International Statistical Classification of Diseases, 10th revision. Results: We included 1,037 patients (0.1%) who had undergone cardiac surgery from a randomized 1,000,000-patient cohort, and 15 patients (1.5%) treated with isolated surgical Afib ablation were excluded. Of these 1,022 patients, 412 (39.7%), 303 (29.2%), and 92 (9.0%) underwent coronary artery bypass, heart valve surgery, and Cox-maze surgery, respectively. Preoperative Afib was associated with higher patient mortality (p=0.028), regardless of the surgical procedure. Patients with preoperative Afib (n=190, 18.6%) experienced a higher cumulative risk of overall mortality (hazard ratio [HR], 1.435; 95% confidence interval [CI], 1.263–2.107; p=0.034). Subgroup analysis revealed a reduced risk of overall mortality with Cox-maze surgery in Afib patients (HR, 0.500; 95% CI, 0.266–0.938; p=0.031). Postoperative cerebral ischemia or hemorrhage events were not related to Afib. Conclusion: Preoperative Afib was independently associated with worse long-term postoperative outcomes after cardiac surgery. Concomitant Cox-maze surgery may improve the survival rate.

Outcomes of Open Repair of Mycotic Aortic Aneurysms with In Situ Replacement

김효현,김도정,주현철 대한흉부외과학회 2017 Journal of Chest Surgery (J Chest Surg) Vol.50 No.6

Background: Mycotic aortic aneurysms are rare and life-threatening. Unfortunately, no established guidelines exist for the treatment of patients with mycotic aortic aneurysms. The purpose of this study was to evaluate the midterm outcomes of the open repair of mycotic thoracic and thoracoabdominal aneurysms and suggest a therapeutic strategy. Methods: From 2006 to 2016, 19 patients underwent open repair for an aortic aneurysm. All infected tissue was extensively debrided and covered with soft tissue. We recorded the clinical findings, anatomic location of the aneurysm, bacteriology results, antibiotic therapy, morbidity, and mortality for these cases. Results: The median age was 62±7.2 years (range, 16 to 78 years), 13 patients (68%) were men, and the mean aneurysm size was 44.5±4.9 mm. The mean time from onset of illness to surgery was 14.5±2.4 days. Aortic continuity was restored in situ with a Dacron prosthesis (79%), homograft (16%), or Gore-Tex graft (5%). Soft-tissue coverage of the prosthesis was performed in 8 patients. The mean follow-up time was 43.2±11.7 months. The early mortality rate was 10.5%, and the 5-year survival rate was 74.9%±11.5%. Conclusion: This study showed acceptable early and midterm outcomes of open repair of mycotic aneurysms. We emphasize that aggressive intraoperative debridement with soft-tissue coverage results in a high rate of success in these high-risk patients.

Outcome of Extracorporeal Ventricular Assist Device for Cardiogenic Shock as a Bridge to Transplantation

김효현,신정훈,김정환,윤영남 대한흉부외과학회 2020 Journal of Chest Surgery (J Chest Surg) Vol.53 No.6

Background: The extracorporeal ventricular assist device (e-VAD) system is designed for left ventricular support using a permanent life support console. This study aimed to deter- mine the impact of temporary e-VAD implantation bridging on posttransplant outcomes. Methods: We reviewed the clinical records of 6 patients with the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile 1, awaiting heart trans- plantation, who were provided with temporary e-VAD from 2018 to 2019. The circuit com- prised a single centrifugal pump without an oxygenator. The e-VAD inflow cannula was inserted into the apex of the left ventricle, and the outflow cannula was positioned in the ascending aorta. The median follow-up duration was 8.4±6.9 months. Results: After e-VAD implantation, lactate dehydrogenase levels significantly decreased, and Sequential Organ Failure Assessment scores significantly improved. Bedside rehabili- tation was possible in 5 patients. After a mean e-VAD support duration of 14.5±17.3 days, all patients were successfully bridged to transplantation. After transplantation, 5 patients survived for at least 6 months. Conclusion: e-VAD may reverse end-organ dysfunction and improve outcomes in INTER- MACS I heart transplant patients.

Late Migration of Amplatzer Septal Occluder Device to the Descending Thoracic Aorta

김효현,이기종,송석원 대한흉부외과학회 2017 Journal of Chest Surgery (J Chest Surg) Vol.50 No.1

Percutaneous closure of atrial septal defect (ASD) has become an increasingly common procedure. Serious complications of the procedure, such as cardiac migration, are rare, and usually occur <72 hours after device placement. In this report, we present the case of a patient who underwent successful surgical treatment for the migration of an ASD occluder device to the thoracic aorta 12 months after ASD closure.

네일 관리방법에 따른 네일의 손상도 비교

김효현,오윤경,문덕환 한국인체미용예술학회 2013 한국인체미용예술학회지 Vol.14 No.3

For the purpose of preparing fundamental data on nail care and assessing the morphological change to nails post nail care, the author examined the roughness with a scanning electron microscope and scanning probe microscope by type of nail care. The subjects were 20 women's nails without any type of nail care within the last 6 months. Free edge nails were sampled 4 times per woman over 6 weeks by type of nail care: cuticle care, nail treatment post cuticle care and nail coloring post cuticle care. For cuticle care, the roughness decreased from a grade of 2.05 to 1.84 after 6 weeks. For nail treatment post cuticle care, roughness decreased from a grade of 1.89 to 1.82 after 6 weeks. For nail coloring post cuticle care, roughness did not change. The author recommends continuous nail care to smooth the nail surface. This study will contribute to furthering the study of nail care

Prevalence and Correlates of Psychiatric Symptoms in North Korean Defectors

김효현,이유진,김하경,김정은,김석주,배승민,조성진 대한신경정신의학회 2011 PSYCHIATRY INVESTIGATION Vol.8 No.3

Objective The aim of the present study is to assess the prevalence of psychiatric symptoms and associated factors in North Korean Defectors (NKDs). Methods One hundred forty-four NKDs (male: 20; female: 124; average age: 40.4±11.7 yrs.) completed the Symptom Checklist-90-Revised (SCL-90-R) and the Center for Epidemiologic Studies Depression scale (CES-D). A stepwise logistic regression analysis was conducted to evaluate factors associated with the psychiatric symptoms of the participants. Results NKDs mainly reported somatization (42.4%) and depressive symptoms (38.9%). Female NKDs showed higher prevalence of somatization (p=0.001), anxiety (p=0.020), hostility (p=0.026) and psychoticism (p=0.022) than males. The presence of physical illness was strongly related to most psychiatric symptoms on the SCL-90-R including somatization (p<0.001), obsessive-compulsive symptoms (p=0.020), interpersonal sensitivity (p=0.031), depression (p<0.001), anxiety (p<0.001), hostility (p=0.011), paranoid ideation (p=0.015)and psychoticism (p<0.001). Younger age, unemployment, lower income, and longer duration of defection were found to be the risk factors of psychiatric symptoms. In regard to mental health service utilization, we found that most (83.3%) of the participants had not received any form of psychiatric help. Conclusion Somatization and depression were the most prevalent psychiatric symptoms in NKDs. Our results suggest that psychiatric symptoms accompany certain sociodemographic and clinical characteristics that are associated with susceptibility to acculturation stressors. An understanding of these factors will be helpful providing appropriate mental health services to NKDs.

부모화된 청소년을 위한 문학치료 사례연구

김효현 한국문학치료학회 2019 문학치료연구 Vol.53 No.-

This study investigates the relationship between the epic of work and the epic of self in a literature therapy program for parentified adolescents. Based on <Simcheongjeon>, this therapy is rooted in the psychological diagnosis of parentification and participants’ sympathy for the life of Simcheong, the main character in the novel, who had to care for her father. Such therapy is then carried on to reflect participants’ own lives. Four early teens with parentification experience participated in the program to consider various aspects of their personal stories. Through the therapeutic power of literature, the study examined the effect of parentification on adolescents and their epic of self. The results showed that epic of self of parentified teens depended on their family relationships and the degree of parentification, implying that their epic of self presented psychological crises associated with having had to sacrifice and care for their parents since they were young. Through the literature therapy program, it is hoped that parentified adolescents will grow up with healthy epic of self by pursuing their own happiness and experiencing emotional separation from their parents. 이 논문은 부모화된 청소년을 위한 문학치료 프로그램을 통해 작품서사와 자기서사와의 관련성을 다양한 매개체를 활용하여 살펴보는 것이다. 본 프로그램은 <심청전>을 바탕으로 부모화된 청소년에 대한 심리적 진단에서 출발하여 ‘심청’이라는 상징적 인물을 만나서 그 인물의 삶에 공명하고 자신의 삶을 성찰하는 과정으로 진행되었다. 실제 부모화경험이 있는 초기 청소년 네 명을 대상으로 다양한 문학치료 프로그램을 운영하여 부모화된 청소년의 자기서사 양상을 여러 면모로 고찰해 보았다. 문학의 치유적 힘을 빌려 우선 부모화 경험이 청소년들에게 어떠한 영향을 주고 있는지. 그 영향으로 인해 어떤 자기서사를 가지고 있는지 구현해 보려 하였다. 부모화된 청소년들의 자기서사는 각 참여자의 개인적인 가족관계 양상 및 부모화 정도에 따라 다르게 나타났다. 어린 시절 부모의 돌봄을 받을 나이에 반대로 부모를 위해 희생하고 의지해야 할 대상을 보살피는 역전된 가족관계의 건강하지 못한 처지에 놓인 청소년의 심리적 위기 상황을 구현하게 된 것이다. 본 프로그램을 통하여 자신의 행복을 위하여 부모로부터 정서적으로 독립하여 건강한 자기서사를 가지고 성장하는 계기가 마련될 것이다.

중화상 환자의 혈행성 캔디다폐렴:단순흉부사진과 세절편 전산화단층촬영(Thin-section CT)소견

김효현,이일성,심야성,김지현,서홍길,조신영,김대순,이길우,강익원 대한영상의학회 1995 대한영상의학회지 Vol.33 No.2

Purpose : To describe plain radiographic and thin-section CT findings of hematogenous candida pneumonia in major burn patients. Material and Method : We reviewed nine cases of hematogenous candida pneumonia in major burn patients who had positive blood culture for candida and findings of pneumonia on plain chest radiograph. On five of nine cases, thin-section CT was done. We evaluated retrospectively nine cases for onset, the pattern, distribution, and size of lesions on plain chest radiograph and thin-section CT. Results : On plain chest radiograph, randomly distributed 2~10mm nodules were seen in six cases(66%) and radomly distributed 10~15mm consolidations in remaining three cases(33%). Lesion occured in 11th to 75th post-burn day(average,34th post-burnday). Other findings were cardiomegaly in three cases, atelectasis in three cases, and pulmonary edema in one case. Thin-section CT showed variable shaped sub pleural nodules in all five cases. The size of nodules were 1~5mm in two cases(40%) and 5~10mm(60%) in three cases. Feeding vessel signs were seen in two cases. Other findings were atelectasis in three cases, cardiomegaly in three cases, ground-glass opacity and interlobular septal thickenings by pulmonary edema in two cases. Conclusion : Plain chest radiographic findings of hematogenous candida pneumonia in major burn patients are randomly distributed nodules or consolidations of variable size. Thin-section CT findings are variable shaped subpleural nodules less than 1cm.

실시간 인터넷 동영상 전송을 위한 효율적인 패킷화 기법

김효현,유국열,Kim Hyo-Hyun,Yoo Kook-Yeol 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.6C

본 논문에서는 패킷화 부가 정보를 효과적으로 감축할 수 있는 패킷화 기법을 제안한다. 이를 위해 기존의 인터넷 동영상 전송을 위한 패킷화 기법을 패킷 길이에 따른 패킷 손실률에 대한 특성을 검증하였다. 인터넷망을 이용한 동영상을 전송 실험을 통해 패킷의 길이가 경로 MTU (path MTU)를 넘을 경우 급격한 패킷 손실률이 증가하고, 이에 따른 화질의 급격한 저하 현상이 발생함을 확인하였다. 그러나 패킷의 길이가 감소하게 되면, 각 패킷별로 부가정보들을 전송해야 하므로, 페이로드에 해당하는 부호화된 동영상 비트열에 할당할 수 있는 비트율의 감소로 인한 화질이 감소하게 된다. 그러므로 효율적인 패킷화를 위해서는 각 패킷들이 경로 MTU에 근접한 길이를 갖도록 패킷화해야 한다. 본 논문에서는 패킷화 문제가 운영체제의 메모리 관리 기법과 유사함을 지적하고, 운영체제에서 사용되는 메모리 관리 기법을 동영상 패킷화에 적용하는 것을 제안하였다. 실험을 통해서 기존의 대표적인 패킷화 방식인 순차적 패킷화 방식과 비교하였고, 제안방식이 패킷화 부가정보를 최대 28.3%까지의 감축할 수 있음을 보였다. In this paper, we propose an efficient packetization method to reduce the packetization overhead. For the purpose, we firstly verify the relationship between packet length and packet loss rate. The empirical results show that as the packet length is larger than the path MTU, the packet loss rate is drastically increased, producing poor visual quality at the receiver side. However, as the length of the packet is reduced, we should transmit more packets per frame and the packetization overhead will be increased. This increase in the packetization overhead reduces the number of bits allocated to the video data, resulting in the low visual quality. Therefore, each packet should be packetized to have the packet length close to the path MTU. In this paper, we show that the this process of the packetization with the constraint on the packet length is very similar to the dynamic storage allocation in the operating system. We had thoroughly surveyed the dynamic storage allocation methods used in the recent operating systems and propose to use the allocation methods for the video packetization. We empirically show that the proposed method can reduce the packetization overhead upto 28.3%, compared with the conventional sequential packetization method which have been widely used in Internet video transmission.