Granulocytic and Monocytic Myeloid-Derived Suppressor Cells are Functionally and Prognostically Different in Patients with Chronic Myeloid Leukemia

Ahn Ari,Park Chan-Jeoung,Kim Min-sun,Cho Young-Uk,Jang Seongsoo,Bae Mi Hyun,Lee Jung-Hee,Lee Je-Hwan,Koh Kyung-Nam,Im Ho Joon 대한진단검사의학회 2021 Annals of Laboratory Medicine Vol.41 No.5

Myeloid-derived suppressor cells (MDSCs) represent phenotypically heterogeneous populations that suppress tumor-specific T-cell responses. MDSCs are produced from myeloid precursors in emergent states and are increased in several hematologic malignancies. We evaluated the differences in the levels and prognostic significance of MDSCs according to the clinical status of chronic myeloid leukemia (CML). The percentages and numbers of granulocytic (g)MDSCs and monocytic (m)MDSCs in peripheral blood (PB) and bone marrow (BM) aspirates were determined by five-color flow cytometry (HLA-DR/CD11b/CD15/CD33/CD14). The median BM-gMDSC% and PB-gMDSC% of the CML group were lower than those of the complete hematologic response (CHR) and control groups (P<0.001). In the CHR group, patients with major molecular response (MMR) showed higher median BM-gMDSC% than those without MMR (P=0.039). Conversely, the PB-mMDSC number of the CML group was higher than those of the CHR and control groups (P<0.001). Patients with high PB-gMDSC number exhibited superior survival to those with low PB-gMDSC number (P=0.021), and patients with high PB-mMDSC% showed inferior survival to those with low PB-mMDSC%, but there was no statistical significance (P=0.182). Increased gMDSCs at CHR may reflect non-leukemic granulopoiesis, and a high number of PB-gMDSCs suggests better prognosis in CML. However, mMDSCs may be associated with malignant conditions and poor prognosis.

Clinical, Laboratory, and Bone Marrow Findings of 31 Patients With Waldenström Macroglobulinemia

Ari Ahn,Chan Jeoung Park,조영욱,장성수,Eul-Ju Seo,JungHeeLee,Dok Hyun Yoon,Cheol Won Suh 대한진단검사의학회 2020 Annals of Laboratory Medicine Vol.40 No.3

Background: Waldenström macroglobulinemia (WM) is a subset of lymphoplasmacytic lymphoma (LPL) with bone marrow (BM) involvement and an IgM monoclonal gammopathy of any level. We aimed to identify the clinical, laboratory, and BM findings of patients with WM and to evaluate the usefulness of CD154 for the diagnosis and prognosis of WM. Methods: We reviewed the medical records and BM studies and/or flow cytometric immunotyping of 31 patients with untreated WM. Semiquantitative immunohistochemistry (CD20, CD138, tryptase, and CD154) of BM was performed. Results: Only six patients presented with symptoms of hyperviscosity syndrome. Eleven patients had solid cancer and/or another hematologic malignancy. Mast cells (MC) increased in all samples, with some in close contact with tumor cells. Tryptase-positive MC (17.1/ high-power fields [HPF], 1.2–72.0/HPF) and CD154-positive MC (8.6/HPF, 0.1–31.1/HPF) were observed. The high CD154-positive MC (≥8.6/HPF) group showed a lower overall five-year survival rate than the low CD154-positive MC (<8.6/HPF) group (71.9% vs. 100.0%; P=0.012). Flow cytometric immunophenotyping of BM aspirates showed increased B lymphocytes and plasma cells with a normal phenotype (CD138+/CD38+/CD19+/CD45+/CD56−). Conclusions: Approximately one third of WM patients showed other malignancies and all patients had increased MC. Immunohistochemistry and flow cytometric immunophenotyping are useful for diagnosing WM, and increased CD154-positive MC can indicate poor prognosis.

Heat Transfer Enhancement in a Channel with Wire-mesh Baffles

Ary Bachtiar Krishna Putra(아리바시아 크리시나 부트라),Soo Whan Ahn(안수환) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.10

The heat transfer characteristics of flow through two inclined wire-mesh baffles in a rectangular channel were investigated experimentally with varying the mesh number of wire screens and inclination angle of the baffles. Two different types of wire meshes, namely dutch weave and plain weave, were used in this experiment. Three kinds of baffle plates with different mesh specifications in the dutch weave and four different kinds in the plain weave were manufactured. Baffles were mounted on bottom wall with varied angle of inclination. Reynolds number was varied from 23,000 to 57,000. It is found that the placement of inclined wire-mesh baffles in the channel affects the heat transfer characteristics by combining both jet impingement and flow disturbance. The wire screen modified the flow structure leading to a change in the heat transfer characteristics. The results show that the baffle plate with the most number of mesh (type SA) has the highest heat transfer rate.

Heat Transfer and Friction Behaviour in a Channel with an Inclined Perforated Baffle

Ary Bachtiar Krishna Putra,Soo Whan Ahn 대한설비공학회 2008 International Journal Of Air-Conditioning and Refr Vol.16 No.2

The effects of the inclined perforated baffles on the distributions of the local heat transfer coefficients and friction factors for air flows in a rectangular channel were determined for Reynolds numbers from 23,000 to 57,000. Four different types of the baffle are used. The inclined baffles have the width of 19.8 ㎝, the square diamond type hole having one side length of 2.55 ㎝, and the inclination angle of 5°, whereas the corresponding channel width-to-height ratio was 4.95. Results show that the heat transfer and friction factor depend significantly on the number of baffle holes and Reynolds number. The friction factor decreases with increasing Reynolds number and the number of holes on the baffle, and the heat transfer performance of baffle type Ⅱ (3 hole baffle) has the best value.

Fluid Flow Resistance in a Channel with Wire-mesh Baffles

Ary Bachtiar Krishna Putra(아리바시아 크리시나 부트라),Soo Whan Ahn(안수환) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.10

An experimental investigation was conducted to examine the fluid flow resistance in rectangular channel with two inclined wire mesh baffles. Two different types of wire meshes, namely dutch weave and plain weave, were used as baffle materials in this experiment. Three kinds of baffles with different mesh specifications were made up of dutch weave type and four different kinds of baffles were made up of plain weave type. The stainless steel wire mesh baffles were mounted on bottom wall with varied angle of baffle inclination. Reynolds numbers were varied from 23,000 to 57,000. Results show that the number of mesh of the baffle plate plays an important role on friction factor behavior. It is found that baffle plate with the most number of mesh (type SA) has the highest fluid flow resistance.

A Numerical Study on Heat Transfer and Friction in Rectangular Channel with Inclined Perforated Baffles

Ary Bachtiar Krishna Putra,Soo-Whan Ahn,Ho-Keun Kang 한국마린엔지니어링학회 2008 한국마린엔지니어링학회지 Vol.32 No.7

Effect of Inclined Ribs Mounted in Square Duct on Heat Transfer and Friction Using Numerical and Experimental Methods

Ary Bachtiar Krishna Putra(아리바시아 크리시나 부트라),Ho Keun Kang(강호근),Dae Hee Lee(이대희),Soo Whan Ahn(안수환) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.11

Numerical predictions and experiment of a hydrodynamic and thermally developed turbulent flow through square channels with one or two ribbed walls were performed to determine the pressure drop and heat transfer. The CFX software package was used for the computations. The rough wall had 45°-inclined square ribs. All four walls in the channel were heated, and a uniform heat flux was maintained on the entire inner heat transfer channel area. Experimental data were also obtained for four Reynolds numbers ranging from 7,600 to 24,900, a pitch-to-rib-height ratio of 8.0, and a rib-height-to-channel hydraulic diameter ratio of 0.0667. The numerical results were in agreement with the experimental data and showed that the values of the local heat transfer coefficient and friction factor in a square channel with two ribbed walls were greater than those with one ribbed wall.

Heat Transfer and Friction Behaviour in a Channel with Inclined Perforated Baffle

Ary Bachtiar Krishna Putra(아리바시아 크리시나 부트라),Soo Whan Ahn(안수환) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.11

This experimental study investigates the local heat transfer enhancement characteristics and the associated frictional head loss in a rectangular channel with a single inclined baffle. Four different types of the baffle are used. The inclined baffles have the width of 19.8 em, the square diamond of 2.55 ㎝ × 2.55 ㎝, and the inclination angle of 5˚. Reynolds number is varied between 23,000 and 57,000. Results show that the heat transfer and friction factor depend significantly on the number of baffle holes and Reynolds number. The friction factor decreases with increasing Reynolds number and the number of holes on the baffle. It is found that the heat transfer performance of baffle type Ⅱ (3 hole baffle) has the best values.

한국인에서 5,10-Methylenetetrahydrofolate Reductase 유전자 다형성 분석 및 임신의 결과에 미치는 영향

김아리 ( Ari Kim ),강은지 ( Eun Ji Kang ),이경아 ( Kyung A Lee ),박세나 ( Se Na Park ),박종순 ( Jong Soon Park ),박보현 ( Bo Hyun Park ),박혜숙 ( Hyesook Park ),박미혜 ( Mi Hye Park ),전선희 ( Sun Hee Chun ),안정자 ( Jung Ja Ahn ) 대한주산의학회 2006 大韓周産醫學會雜誌 Vol.17 No.3

목적: 본 연구는 한국인 임신 여성에서 MTHFR 유전자형 변이와 혈청내 호모시스테인 및 엽산의 농도와 이들이 임신에 미치는 영향을 알아보고자 하였다. 방법: 임신부 600명에게서 혈액을 채취하여 얻어진 DNA로 MTHFR C677T와 A1298C 유전자의 다형성을 PCR-RELP로 분석하였고 혈청내 호모시스테인은 HPLC 방법으로, 엽산은 RIA 방법으로 측정하였다. 결과: 혈청내 호모시스테인은 MTHFR C677T 유전자형이 C/C형이나 C/T인 군에 비해 T/T인 군에서 유의하게 높았으며 MTHFR A1298C 유전자형이 A/C형이나 C/C인 군에 비해 A/A인 군에서 역시 유의하게 높았다( p<0.05). 혈청 호모시스테인은 모든 MTHFR 유전자형에서 혈청 엽산농도와 역상관관계를 보였으나, 변이형 유전자형(T/T와 A/A유전자형)에서 더 큰 역 상관관계를 보였다. 15?mol/L 이상의 고호모시스테인혈증의 임신부에서 임신 주수와 출생체중이 36.1주, 3053.8 g으로 15 ?mol/L미만인 군의 38.3 주, 3215.3 g 보다 유의하게 낮았다( p<0.05). 결론: 혈청 호모시스테인의 농도는 MTHFR C677T와 A1298T 유전자의 다형성에 의해 영향을 받으며, MTHFR C677T와 A1298T 유전자의 다형성과 혈청 호모시스테인은 모두 임신주수와 신생아의 체중에 영향을 미친다. Objective: The purpose of this study was to analyze MTHFR polymorphism among the Korean population and to evaluate the relationship between serum levels of homocysteine and MTHFR polymorphism and also to investigate the effect on pregnancy outcomes. Methods: DNA was extracted from whole blood of 600 pregnant women. All samples were genotyped for the C677T and A1298C polymorphisms in MTHFR gene by PCR-RELP assay. Serum levels of homocysteine and folate were measured by high performance liquid chromatography for homocysteine and radioassay for folate. Pregnancy outcomes were estimated by gestational weeks and birth weights of newborns. Results: Serum homocysteine was higher in women with the T/T genotype than those with the C/T or C/C genotype of the MTHFR C677T polymorphism (p<0.05). And also serum homocysteine was higher in women with the A/A genotype than those with the A/C or C/C genotype of the MTHFR A1298C polymorphism (p<0.05). Serum homocysteine was negatively correlated with serum folate in all MTHFR genotypes, especially prominent in T/T genotype of MTHFR C677T polymorphism and A/A genotype of MTHFR A1298C polymorphism. Gestational age and the birth weight of infant from hyperhomocysteinemic mothers whose homocysteine levels higher than 15 μmol/L were 36.1 weeks, 3053.8 g, respectively, which were significant lower than those from normohomocysteinemic mothers (38.3 weeks, 3,215.3 g) (p<0.05). Conclusion: Serum homocysteine was influenced significantly by MTHFR C677T polymorphism and MTHFR A1298C polymorphism. MTHFR C677T and A1298C polymorphism and serum homocysteine levels affect pregnancy outcomes, although not mainly by serum folate level.

Ultrasonic Manipulation of Magnetic Particles in a Microfluidic Channel

Siddique, Ariful Haque,Cho, Seung Hyun,Ahn, Bongyoung,Kim, CheolGi Korean Society for Precision Engineering 2014 International Journal of Precision Engineering and Vol.15 No.7

In microfludic biosensor applications, many kinds of magnetic particles have been employed due to their bioaffinity property, so the appropriate manipulation of magnetic microparticles is important. In this work, we demonstrated the alignment of magnetic beads (diameter <TEX>$2.8{\mu}m$</TEX>) and nanowires (length <TEX>${\leq}6{\mu}m$</TEX> & diameter <TEX>${\approx}$</TEX> 50 nm) using ultrasonic standing wave (USW) in a steel-acrylic microfluidic channel (<TEX>$660{\mu}m$</TEX> width) in the aim of concentrating them to a sensor area to enhance the performance of a sensor. Ultrasonic standing wave field generates the radiation force to concentrate microparticles at the pressure nodal planes. To generate a standing wave inside the channel, an ultrasound of 2.25 MHz resonance frequency was applied as a resonance frequency of the channel. Moreover, it was demonstrated here that the position of the aligned magnetic particles could be controlled by changing the applied frequency. These successful alignment and position control can be a milestone for future research which targets to improve the sensitivity of microfluidic sensors using magnetic particles.