Monitoring the Antiplatelet Effect of Cilostazol with Light Transmission Aggregometer: Two Cases of Possible Cilostazol Resistance

심효은,장성수,박찬정,지현숙,이승환,박성욱 대한진단검사의학회 2016 Laboratory Medicine Online Vol.6 No.4

Background: Coronary artery disease is an important cause of death in adults and stent insertion is one of the treatment modalities. The most severe adverse effect of a stent insertion is the formation of a thrombus; therefore, antiplatelet agents are used. The addition of cilostazol to low-dose aspirin and clopidogrel results in a better antiplatelet effect. However, laboratory tests to monitor the effect of cilostazol are insufficient. Methods: We tested the inhibitory effect of cilostazol using maximal platelet aggregation in 20 healthy volunteers. Conditions for incubation and concentrations of cilostazol and prostaglandin E1 (PGE1) were established and aggregation was induced by 5´-adenosine diphosphate (ADP) and measured with light transmission aggregometry (LTA). Blood samples were incubated with 1 μM and 2 μM cilostazol for 10 minutes at room temperature, and 80 nM PGE1 was added and incubated for an additional 10 minutes. Aggregation was induced by ADP and reactivity was evaluated. Results: The average maximum aggregation (MA) was 58.1% at 1 μM cilostazol and 22.0% when PGE1 was added. The average MA was 42.8% when cilostazol concentration was increased to 2 μM and 21.2% when PGE1 was added. Average inhibition of aggregation at 1 μM cilostazol was not statistically significant (P=0.085), but was significant (P=0.004) at 2 μM cilostazol. Aggregation was not inhibited even with 2 μM cilostazol and PGE1 in 2 volunteers, which suggests possible resistance to cilostazol. Conclusions: We designed a method to monitor the effect of cilostazol using in vitro incubation with PGE1.

중심정맥관 관련 Tsukamurella pulmonis 균혈증 1예

심효은,성흥섭,백승미,남궁승,김미나,김용균,이규형 대한진단검사의학회 2009 Annals of Laboratory Medicine Vol.29 No.1

Tsukamurella pulmonis는 호기성 actinomycetes에 속한 다. 저자들은 T. pulmonis 균혈증 1예를 경험하여 보고하고자 한다. 급성림프성 백혈병인 39세 남자가 입원 9일째 골수 이식 을 받았다. 7일째 고열이 발생하여 vancomycin을 추가한 후 열 이 해소되었으나 vancomycin, meropenem, amphotericin B 치료를 계속하였는데도 16일째 고열이 재발하여 19일째 Hickman 카테터(HC)를 제거하였다. 7, 16, 19일째 각각 HC를 통해 채혈한 혈액 한 쌍과 말초 혈관의 혈액 두 쌍 등 3쌍씩 혈액배양 을 실시하였고, 제거했던 HC의 말단부도 배양하였다. HC로 채 취한 혈액배양의 모든 호기성 병과 말초혈관에서 얻은 혈액 한 병, HC 말단부 배양에서 길고, 가는 반듯한 그람양성 막대균이 분리되었고, 변법 Kinyoun 염색에 양성이었다. 배양 3일째에 작고 비용혈성의 회색의 거친 집락이 자랐고, 배양을 연장하면 집락이 크고 납작해졌다. 균은 catalase, urease 양성이었으며 triple sugar iron 한천배지에서 알칼리 사면/알칼리 고층반응 을 보이고, hypoxanthine을 분해하였다. 1,296 bp의 16S rRNA 염기서열 분석결과 T. pulmonis DSM 44142T과 100% 일치하 였다. 본 증례는 T. pulmonis에 의한 국내 첫 균혈증 보고이다. Tsukamurella pulmonis is an aerobic actinomycete. We report a catheter-related bacteremia of T. pulmonis. A 39 yr-old male with ALL was hospitalized to receive bone marrow transplantation (BMT). Although the patient developed a high fever at the 7th hospital day (HD), it subsided with vancomycin treatment, and he received BMT at 9th HD. Fever resurged at 16th HD despite sustained treatment with vancomycin, meropenem, and amphotericin B, but subsided with removal of Hickman catheter (HC) at 19th HD. Three sets of blood cultures comprising one from the HC and two from venipunctures were taken at 7th, 16th, and 19th HD, and the distal tip of the HC was also cultured. The aerobic vials of all 3 HC-withdrawn blood cultures and one peripheral blood culture taken at 19HD and the HC tip culture grew long, straight, thin gram-positive rods that were positive on modified Kinyoun stain. This organism showed tiny, rough, grey colonies after 3-day incubation and grew to large flat colonies when incubation was extended. It was catalase-positive, ureasepositive, and alkaline-slant/alkaline-deep on triple sugar iron agar, and hydrolyzed hypoxanthine. The sequence of 1,296 base pairs of 16S rRNA of this organism showed a 100.0% homology with the published sequence of T. pulmonis DSM 44142T. To our knowledge, this is the first report of T. pulmonis bacteremia in Korea.

계약 학습이 하위권 고등학생들의 자기주도적 영어쓰기 활동에 미치는 영향

심효은,이호 21세기영어영문학회 2017 영어영문학21 Vol.30 No.2

The purpose of this study is to examine the influences of contract learning on high school students' self-directed English writing. The participants were 5 high school students of emerging level with rare experiences of English writing. They volunteered for contract learning and compiled a learning contract and daily learning planner. The particular research questions are “How does contract learning influence the students' self-directed learning?” and “What effects does the use of contract have on students' perception of English writing?” During the contract learning, participants had constant face-to-face interaction with their teacher-researcher. The teacher-researcher checked their learning process by means of interviews. Analyzing the data from their self-directed testing sheets, their daily planners, and the interviews, the teacher-researcher found that contract learning was an effective way to improve students' self-direction and that students showed a high level of satisfaction because contract learning made it possible for them to monitor and control their own writing.

Anti-Oka Antibody: The First Case Report in Korea

심효은,박현준,이춘성,권석운 대한수혈학회 2010 大韓輸血學會誌 Vol.21 No.2

Anti-Oka was detected in a 56-year-old female patient who was admitted for surgical treatment of degenerative scoliosis. Because Oka is a high-incidence antigen, anti-Oka antibody is extremely rare. No case of hemolytic transfusion reaction or hemolytic disease of the fetus and newborn caused by anti-Oka antibody has been reported so far, however, it is likely that anti-Oka is clinically significant based on several in vivo and in vitro studies. When a patient who is bearing anti-Oka needs transfusion of RBCs, transfusion of autologous blood or Ok(a-)RBCs from family members is recommended. (Korean J Blood Transfus 2010;21:171-174)

Cluster Containing More Than 20 CD3-Positive Cells in Bone Marrow Biopsy Is a Candidate Prognostic Indicator in Peripheral T-Cell Lymphoma, Not Otherwise Specified

심효은,장성수,허주령,윤덕현,서철원,박찬정 대한진단검사의학회 2019 Annals of Laboratory Medicine Vol.39 No.2

Assessment of bone marrow (BM) involvement in peripheral T-cell lymphoma, not otherwise specified (PTCL) is straightforward in cases of extensive involvement but difficult in cases of minimal to partial involvement. We evaluated the usefulness of CD3 as an immunohistochemical marker for assessing BM involvement in PTCL patients. BM biopsies of 92 PTCL patients were immunohistochemically stained for CD3, CD4, CD8, CD20, and CD56, and evaluated by two hematopathologists. CD3 positivity was graded according to the proportion of CD3-positive cells and the number of CD3-positive cells in a cluster. These criteria were used to determine the cut-offs at which significant differences in progression-free survival (PFS) and overall survival (OS) were observed. Multivariate analysis controlling the International Prognostic Index (IPI) score and its individual factors revealed that >20 CD3-positive cells in a cluster adversely affected PFS (relative risk [RR], 2.1; 95% confidence interval [CI], 1.0–4.3; P=0.047) and OS (RR, 2.4; 95% CI, 1.1–5.1; P=0.028) independent of IPI score. A cluster with >20 CD3-positive cells is a candidate indicator for BM involvement in PTCL.

POEMS Syndrome: Bone Marrow, Laboratory, and Clinical Findings in 24 Korean Patients

심효은,설창안,박찬정,조영욱,서을주,이정희,윤덕현,서철원,박상혁,장성수 대한진단검사의학회 2019 Annals of Laboratory Medicine Vol.39 No.6

POEMS syndrome is a rare paraneoplastic syndrome, which includes polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes due to plasma cell (PC) neoplasm. Diagnosis of this disease is challenging because of its rarity and complex clinical manifestations. We attempted to identify the key clinical features and characteristic bone marrow (BM) findings of POEMS syndrome, by reviewing the medical records and BM analyses of 24 Korean patients. Frequent clinical manifestations included polyneuropathy (100%), monoclonal gammopathy (100%), organomegaly (92%), extravascular volume overload (79%), and endocrinopathy (63%). The BM analyses revealed mild PC hyperplasia (median PCs: 5.5%) and frequent megakaryocytic hyperplasia (88%), megakaryocyte clusters (88%), and hyperlobation (100%). Flow cytometry of BM aspirates using CD138/CD38/CD45/CD19/CD56 showed normal (67%, 4/6) or neoplastic PC immunophenotypes (33%, 2/6). A diagnosis of POEMS syndrome must be considered when a patient suspected of having PC dyscrasia shows the above clinical presentation and BM findings.

Direct numerical simulation of turbulence modification by microbubbles in homogeneous isotropic turbulence

Hyoeun shim(심효은),Changhoon Lee(이창훈) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.11

The modulation of homogeneous and isotropic turbulence by microbubbles is investigated by using direct numerical simulation at Taylor scale reynolds number Re<SUB>λ</SUB> = 62. Within the different classes involved in the two-phase flows, the focus of present work is on the modification of turbulent flow by bubbles, immersed dilutely in the flow. The trajectory of bubbles is calculated by using Lagrangian tracking and the motion of bubbles is assumed to be governed by the added mass, gravity, drag and lift force. The effect of microbubbles on the flow is incorporated by applying the point-force approximation. The obtained results show that momentum transfer from bubbles to the flow behaves non-uniformly across the dissipation spectrum. The spectrum exhibits the enhancement of energy at high wavenumbers, while the converse is observed at low wavenumbers. This in turn is consistent with observations of Mazzitelli et al(2003) and van denBerg et al(2006).

Clinical Relevance of Time-to-positivity in BACTEC9240 Blood Culture System

박상혁,심효은,윤남섭,김미나 대한진단검사의학회 2010 Annals of Laboratory Medicine Vol.30 No.3

Background : Continuous monitoring systems have allowed determination of the time-to-positivity (TTP). We evaluated the clinical relevance of TTP in the BACTEC9240 system (Becton-Dickinson, USA). Methods : A total of 2,354 vials of positive blood cultures were evaluated over 2 months. TTP was monitored from each of BACTEC Plus Aerobic/F (BD) or Pediatric Plus/F and Lytic Anaerobic/F bottles, and the differential time-to-positivity (DTP) for blood samples drawn simultaneously via catheter and a peripheral site was determined. Results : The average TTP of the positive vials was 17.4 hr, and 79.9% and 95.2% of the vials showed positivity within 24 and 48 hr, respectively. While the average TTP values for Aeromonas hydrophila, Bacillus cereus, Acinetobacter baumannii, and Streptococcus pneumoniae were less than 10 hr, those for Candida spp., anaerobes, Propionibacterium acnes, Corynebacterium spp, Bacillus spp. other than cereus, and coagulase-negative staphylococci were 35.3, 27.0, 56.8, 45.8, 23.0, and 26.3 hr, respectively. The negative predictive values of TTP over 24 hr to predict Staphylococcus aureus among staphylococci and S. pneumoniae among a-hemolytic streptococci were 76.7% and 100%, respectively. Enterobacteriaceae and Enterococcus faecalis showed shorter TTP in anaerobic vials than in aerobic vials. DTP of more than 2 hr was observed for 27.8%, 72.2%, and 45.5% of S. aureus, S. epidermidis, and Candida spp. Conclusions : TTP can be used to discriminate pathogens and contaminants. The shorter TTP in anaerobic vials of certain Enterobacteriaceae and Enterococcus spp. would facilitate further identification. DTP is useful for diagnosing catheter-related bloodstream infection by S. aureus, S. epidermidis, and Candida spp. (Korean J Lab Med 2010;30:276-83)

유세포검사에 의한 림프구아형검사에서 Gating 시 CD45의 필요성 및 NK세포 측정 시 CD16의 중요성

최영현,심효은,박찬정,한상희,황금록,장성수,지현숙 대한진단검사의학회 2013 Laboratory Medicine Online Vol.3 No.2

Background: Clinical and Laboratory Standards Institute (CLSI) guidelines (H42-A2) recommend the “CD45/SSC” gating method for assays on lymphocyte subset enumeration and CD16 exclusion for assays enumerating NK cells. In contrast, the Flow Cytometry Checklist (06/17/2010) of the College of American Pathology does not recommend a specific lymphocyte gating method, but recommends the correction of lymphocyte subset results for lymphocyte gate purity. Methods: We compared lymphocyte subset results of EDTA-treated blood from 102 patients with various diseases and 12 normal controls, using 3 lymphocyte gating methods (CD45/SSC, FSC/SSC, and lymphocyte gate purity correction after FSC/SSC gating), and assessed the proportion of CD56-/CD16+ NK cells within the total NK cell population. Results: Lymphocyte gate purity increased as the percentage of lymphocytes increased. However, lymphocyte subsets that consistently showed high lymphocyte gate purity could not be identified. The purity of the T cell population differed significantly depending on the gating method used:CD45/SSC vs. FSC/SSC, P =0.027; CD45/SSC vs. gate purity correction after FSC/SSC, P =0.002. However, the lymphocyte gate purity correction after FSC/SSC gating did not significantly improve the accuracy of the lymphocyte subset enumeration assay using FSC/SSC gating. The subset of CD56-CD16+ NK cells, constituted an average of 17.1% of total NK cells. Patients had higher proportions of CD56-CD16+ NK cells (13.1-25.5%)than did the normal controls (9.52%). Conclusions: In flow cytometric assays to evaluate lymphocytic subsets, the CD45 is inevitable for lymphocyte gating, whereas the measurement of CD16 is essential for the evaluation of NK cell proportions. 배경: Clinical and Laboratory Standards Institute 가이드라인(H42-A2)에서는 림프구아형분석을 위하여 ‘CD45/SSC’ gating법을 사용하고 NK세포아형 측정 시 CD16를 사용하지 않고 CD56만을 사용할 것을 권장하고 있다. 또한 CAP의 유세포검사 체크리스트에서는 림프구아형검사 시 gating을 위하여 특정한 gating방법의 사용을 권장하지 않고, 단지 gate 순도에 따라 림프구아형검사의 결과를 교정할 것을 권장하고 있다. 방법: 102명의 환자군과 12명의 정상 대조군으로부터 EDTA 혈액을 채취하여 세 가지의 gating법(CD45/SSC, FSC/SSC, FSC/SSCgating 후 gate 순도를 이용한 교정)으로 림프구아형검사를 실시하여 그 결과를 각각 비교하였고, NK세포 가운데 CD56-/CD16+ NK세포아형의 백분율을 평가하였다. 결과: 림프구백분율이 증가할수록 림프구 gate의 순도가 증가하는 것을 알 수 있었으나 높은 림프구 순도를 나타내는 특정한 림프구백분율은 알 수 없었다. T세포의 경우 gating법에 따라 결과가달라졌는데(CD45/SSC와 FSC/SSC 비교 시 결과값의 차이P = 0.027, CD45/SSC와 FSC/SSC gating 후 림프구순도로 교정 비교 시 결과값의 차이 P = 0.002), FSC/SSC gating 후 림프구순도로교정하는 방법이 FSC/SSC gating법에 비해 정확도가 증가되지 않았다. CD56-CD16+ NK세포아형은 총 NK세포의 17.1% (평균)를차지하였으며 환자군(13.1-25.5%)에서 대조군(9.5%) 보다 더 높은비율을 차지하였다. 결론: 유세포검사에 의한 림프구아형 측정에서 CD45는 gating 시반드시 사용되어야 하고, NK세포 측정 시 CD16 사용이 필수적이다.

A Case of T-cell Large Granular Lymphocytic Leukemia Presented as Pulmonary Hypertension

조은,심효은,정종헌 대한내과학회 2022 대한내과학회 추계학술대회 Vol.2022 No.2