Skin entrance dose for digital and film radiography in Korean dental schools

Cho, Eun-Sang,Choi, Kun-Ho,Kim, Min-Gyu,Lim, Hoi-Jeong,Yoon, Suk-Ja,,Kang, Byung-Cheol 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.4

Purpose : This study was aimed to compare skin entrance dose of digital radiography with that of film radiography and to show the dose reduction achievement with digital systems at 11 dental schools in Korea. Materials and Methods : Forty six intraoral radiographic systems in 11 dental schools were included in this study. Digital sensors were used in 33 systems and film was used in 13 systems. Researchers and the volunteer visited 11 dental schools in Korea. Researchers asked the radiologic technician (s) at each school to set the exposure parameters and aiming the x-ray tube for the periapical view of the mandibular molar of the volunteer. The skin entrance doses were measured at the same exposure parameters and distance by the technician for each system with a dosimeter (Multi-O-Meter : Unfors instruments, Billdal, Sweden). Results : The median dose was 491.2 μGy for digital radiography and 1,205.0 μGy for film radiography. The skin entrance dose digital radiography was significantly lower than that of film radiography (p<0.05). Conclusion : Fifty-nine percent skin entrance dose reduction with digital periapical radiography was achieved over the film radiography in Korean dental schools.

Retroperitoneal Mucinous Cystadenoma

Gyu Yeol Kim(김규열),Dae Hwa Choi(최대화),Young Chul Lim(임영철),Byung Kyun Ko(고병균),Sang June Park(박상준),Yang Won Nah(나양원),Hong Rae Cho(조홍래),Chang Woo Nam(남창우) 대한외과학회 2008 Annals of Surgical Treatment and Research(ASRT) Vol.74 No.1

일차성 후복막 점액성 낭선종은 흔치 않은 종양으로 여성에게만 발생하며, 수술 전에 정확한 진단을 하기 매우 어렵다. 하지만, 이러한 낭성 종양의 낭액에서의 증가된 암태아성항원의 수치가 일차성 후복막 점액성 낭선종의 유용한 진단 지표가 될 수 도 있다. 완전 절제가 이 종양의 적절한 치료이다. 또한, 수술 중 복강 내 타 장기들을 누르거나 할 필요가 없으며, 소장 및 대장이 손상될 위험을 줄일 수 있다는 측면에서 후복막 접근이 복강 내 접근 보다 유용한 방법일 수 있다. 저자들은 후복막 접근을 통해 성공적으로 절제한 일차성 후복막 점액성 낭선종의 경험을 보고한다. We present a case of a primary retroperitoneal mucinous cystadenoma, which is a relatively rare tumor found exclusively in women. This tumor is difficult to correctly diagnose preoperatively. Although there is little published information regarding the CEA levels in the cystic fluid of cystic tumors arising in the retroperitoneum, a high CEA level in the cystic fluid is a useful diagnostic marker for a primary retroperitoneal mucinous tumor. The appropriate management of retroperitoneal mucinous cystadenomas is the total removal of the cyst. The retroperitoneal approach for retroperitoneal cystic tumors is useful, has a lower risk of traumatizing the bowel than the intra-abdominal approach, and does not require compression of the other organs. We report the successful resection of a retroperitoneal mucinous cystadenoma through the retroperitoneal approach.

Ex Vivo Generated Human Cord Blood Myeloid-Derived Suppressor Cells Attenuate Murine Chronic Graft-versus-Host Diseases

Lim, Ji-Young,Ryu, Da-Bin,Park, Mi-Young,Lee, Sung-Eun,Park, Gyeongsin,Kim, Tai-Gyu,Min, Chang-Ki Elsevier 2018 BIOLOGY OF BLOOD AND MARROW TRANSPLANTATION Vol.24 No.12

<P><B>Abstract</B></P> <P>Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells with anti-inflammatory activity, and expanded murine MDSCs are capable of attenuating preclinical acute graft-versus-host disease (aGVHD) severity. Two murine cGVHD models were used to evaluate the effectiveness of ex vivo cultured human cord blood (hCB) MDSCs in chronic GVHD (cGVHD). First, GVHD recipients surviving in a classic C57BL/6 into MHC-mismatched BALB/c aGVHD model developed cGVHD. Second, donor pretreatment with granulocyte colony-stimulating factor (G-CSF) induced cGVHD. hCB-MDSCs (1 × 10<SUP>6</SUP>) were intravenously injected to determine their preventive effects (on days 5, 7, 10, and 21) or therapeutic effects (on days 21, 28, and 35). In the first model the onset of clinical cutaneous cGVHD was significantly delayed in preventive hCB-MDSCs–treated allogeneic recipients. Pathologic scoring of target organs confirmed these clinical results. Importantly, thymic tissues of GVHD mice treated with hCB-MDSCs were less severely damaged, showing higher numbers of double (CD4 and CD8) positive T cells with reduced expansion of donor-type CD4 and CD8 T cells. Moreover, late infusion of hCB-MDSCs controlled the severity of established cGVHD that had occurred in control recipients. In the second model, cGVHD induced by G-CSF–mobilized stem cell graft was associated with promotion of Th 17 and Th 2 differentiation. hCB-MDSCs attenuated clinical and pathologic cGVHD severity. Increased production of IL-17 and more infiltration of T cells and macrophages in cGVHD mice were markedly reduced after hCB-MDSCs treatment. Importantly, Foxp3<SUP>+</SUP> regulatory T cells and IFN-γ–producing T cells were expanded, whereas IL-17– and IL-4–producing T cells were decreased in allogeneic recipients of hCB-MDSCs. Taken together, these results showed that hCB-MDSCs have preclinical capability of attenuating cGVHD by preserving thymus function and regulating Th 17 signaling, suggesting a possible therapeutic strategy for clinical application.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Human cord blood (hCB) can be a source of immunosuppressive MDSCs. </LI> <LI> Administration of hCB-MDSCs attenuates cGVHD in preclinical models. </LI> <LI> hCB-MDSCs reduce thymic damage with less donor-derived T cell expansion. </LI> <LI> cGVHD protection by hCB-MDSCs correlate with reversal of Th 17 skewing. </LI> <LI> hCB-MDSCs modulate helper T cell subset and expand FoxP3 Treg. </LI> </UL> </P>

The role of aquatic ecology in constructed wetlands using physico-chemical characteristics and contribution of microorganisms in sediment

Sang Gyu Lee(이상규),Dong-Cheol Seo(서동철),Se-Won Kang(강세원),Ik-Won Choi(최익원),Byung-Jin Lim(임병진),Jong-Hwan Park(박종환),Kap-Soon Kim(김갑순),Jun-Bae Lee(이준배),Jong-Soo Heo(허종수),Ju-Sik Cho(조주식) 한국토양비료학회 2011 한국토양비료학회 학술발표회 초록집 Vol.2011 No.10

Corrosion phenomena of PEO-treated films formed in solution containing Mn, Mg, and Si ions

Lim, Sang-Gyu,Choe, Han-Cheol Elsevier 2019 APPLIED SURFACE SCIENCE - Vol.477 No.-

<P><B>Abstract</B></P> <P>In this study, corrosion phenomena of PEO-treated films formed in solution containing Mn, Mg, and Si ions were researched using various experimental instruments.</P> <P>Ti-6Al-4V ELI disk (grade 5, Timet Co. Ltd, Japan Diameter; 10 mm) was used as a specimen for plasma electrolytic oxidation (PEO) treatment. The specimen was cleaned and used as an anode, and a platinum rod was used as a cathode in the electrolyte containing Mn, Mg, and Si ions for PEO process. The potentiodynamic polarization and AC impedance tests for corrosion behaviors were carried out in 0.9% NaCl solution. The surfaces of the PEO-treated Ti-6Al–4V specimens were observed by a field emission scanning electron microscopy (FE-SEM, S-4800 Hitachi, Japan) and energy dispersive X-ray spectroscopy (EDS).</P> <P>In the case of PEO-treated surface in electrolyte containing Mn ions, precipitates of Mn were mainly formed on around the pore, and the number of pores decreased, as Mn contents increased. From the result of potentiodynamic test, the corrosion potential of PEO-treated surface in solution containing Mn ion was higher than that of in solution containing Mg ion. In the case of PEO-treated surface in electrolyte containing Mn ions, second anodic peaks showed in the passive region. From the AC impedance test, in the case of 5Mg5Mn/5Si specimen, polarization resistance is higher than those of other specimens.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Corrosion phenomena of PEO-treated films formed in solution containing Mn, Mg, and Si ions were studied. </LI> <LI> In PEO-treated surface in electrolyte containing Mn ions, Mn precipitates were mainly formed on around the pore. </LI> <LI> Number of pores on the PEO-treated surfaced decreased, as Mn contents increased. </LI> <LI> Corrosion potential of PEO-treated surface in Mn ion solution was higher than that of in solution containing Mg ion. </LI> <LI> From the AC impedance test, in the case of 5Mg5Mn/5Si specimen, polarization resistance is higher than those of others. </LI> </UL> </P>

Root cause of thermal sleeve loosening in optimized power reactor 1000 unit 5 and 6 Part (I)

Sang-Gyu Lim,Sung-Yeop Jung,Sang-Nyung Kim 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.4

Four of safety injection (SI) nozzles in a 1000 MWe-class Optimized Power Reactor (OPR-1000) are fitted with thermal sleeves (T/S) to alleviate thermal fatigue. Thermal sleeves in #3 and #4 of Younggwang (YGN) & Ulchin (UCN) nuclear power plant are manufactured out of Inconel-600 and fitted solidly without any problem, whereas YGN and UCN in #5 and #6, also fitted with thermal sleeves made of Inconel-690 for increased corrosion resistance, experienced a loosening of thermal sleeves except T/S of YGN #5-1A. To identify the root cause of T/S loosening, three suspected causes were analyzed: (1) the shear force of flow on the T/S when the safety SI nozzle was in operation, (2) the differences between Inconel-600 and Inconel-690 in terms of physical and chemical properties (notably the thermal expansion coefficient), and (3) the positioning error in explosive expansion of the T/S as well as the asymmetric expansion of T/S. It was confirmed that none of the three suspected causes could be considered as the root cause. However, after reviewing the design change history from the Palo Verde nuclear power plant to YGN and UCN #3,4 and #5,6, it was realized that the two stage design modifications (in terms of groove depth & material) made an additional explosive energy required by 172% in aggregate, but the amount of gunpowder and the explosive expansion method were the same as before, resulting in insufficient explosive force that led to poor thermal sleeve expansion. T/S measurement data and rubbing copies also support this conclusion. And the T/S loosening was also attributable to lenient quality control before and after fitting the T/S that resulted in significant uncertainty. In addition, it is our judgment that the acceptance criterion applicable to T/S fitting was not strict enough, failing to single out thermal sleeves that were not expanded sufficiently. Lastly, the acceptance criterion was scientifically revised to incorporate the thinning effect and inherent uncertainties of measurements.

Formation of bone-like apatite after plasma electrolytic oxidation in solution containing functional material

Sang-Gyu Lim,Han Cheol Choe 대한치과재료학회 2018 대한치과기재학회 학술대회 Vol.2018 No.4

Predictive factors of acute kidney injury in patients undergoing rectal surgery

( Sung Yoon Lim ),( Joon Yong Lee ),( Ji Hyun Yang ),( Young Joo Na ),( Myung Gyu Kim ),( Sang Kyung Jo ),( Won Yong Cho ) 대한신장학회 2016 Kidney Research and Clinical Practice Vol.35 No.3

Background: Despite major advance in surgical techniques from open surgery to robot-assisted surgery, acute kidney injury (AKI) is still major postoperative complication in rectal surgery. The purpose of this study is to compare the incidence of postoperative AKI according to different surgical techniques and also the risk factors, outcomes of AKI in patients undergoing rectal cancer surgery. Methods: A retrospective medical chart review was done in a total of 288 patients who received proctectomy because of rectal cancer from 2011 to 2013. Results: The mean patient age was 62 ± 12 years, and male was 64.2%. Preoperative creatinine was 0.91 ± 0.18 mg/dL. Open surgery was performed in 9%, and laparoscopy assisted surgery or robot assisted surgery were performed in 54.8% or 36.1% of patients, respectively. AKI developed in 11 patients (3.82%), 2 (18%) of them received acute hemodialysis. Incidence of AKI was not different according to the surgical technique, however, the presence of diabetes, intraoperative shock, and postoperative ileus was associated with the development of AKI. In addition, AKI patients showed significantly longer hospital stay and higher mortality than non- AKI patients. Conclusion: Our study demonstrated that despite advances in surgical techniques, incidence of postoperative AKI remains unchanged and also that postoperative AKI is associated with poor outcome. We also found that presence of diabetes, intraoperative shock and postoperative ileus are strongly associated with the development of AKI. More careful attention should be paid on high risk patients for the development of postoperative AKI regardless of surgical techniques.

A Grid Web Portal for Aerospace

Sang Boem Lim,Joobum Kim,Nam Gyu Kim,June H. Lee,Chongam Kim,Yoonhee Kim 한국전산유체공학회 2006 한국전산유체공학회 학술대회논문집 Vol.2006 No.5

Experiences of renal transplants from donors with renal cell carcinoma after ex vivo partial nephrectomy

Sung Yoon Lim,Myung Gyu Kim,Kwon Tae Park,Cheol Woong Jung 대한외과학회 2017 Annals of Surgical Treatment and Research(ASRT) Vol.92 No.5

Purpose: Routine evaluation of kidney donors occasionally reveals an incidental renal mass with an otherwise satisfactory kidney function. The use of such a kidney with an enhancing mass for transplantation is a matter of debate owing to a possible risk of transmission of donor malignancies. We report our experience of kidney transplants from donors with renal cell carcinoma, after ex vivo resection of the renal mass. Methods: Two women aged 44 and 56 years were diagnosed with enhancing renal masses measuring 0.9 cm and 0.7 cm, respectively, during donor evaluation for kidney transplantation. Both patients and their families were informed of a potential risk of recurrent renal cell carcinoma following transplantation. Results: Renal function test results of both donors satisfied the living donor selection criteria. Laparoscopic live donor nephrectomy was performed with ex vivo resection of renal masses on the bench table. Immediate pathological analysis revealed a renal cell carcinoma with a margin of normal renal parenchyma before transplantation. Regimens based on mammalian target of rapamycin inhibitors, which are known for their antitumoral properties, were used for immunosuppression in both recipients. None of the recipients showed recurrence or metastasis during the follow-up period, which was longer than 3 years after transplantation. Conclusion: In light of the ongoing shortage of kidney donors, kidneys with small renal cell carcinoma could be considered for transplantation after appropriate removal of the lesion, with a very low risk of recurrent disease.