Effects of Pilger Rolling and Heat Treatment on Microstructure and Corrosion Resistance of Ag-electroplated 304 Stainless Steel Tubes

Hyun Park,Woo‑Jin Lee,Jae‑Han Son,Han‑Kyun Shin,Sung‑Kyu Hong,Hyo‑Jong Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

We introduce a cost-effective method that combines electroplating with metal cold working processes to manufacture compositetubes with robust corrosion resistance. First, a 3-step electroplating process was developed to form an adhesive anduniform Ag coating on the outer wall of a 304 stainless steel tube. The process consisted of a Ni-strike step for removing thepassivation layer of the initial 304 tube, Cu deposition for smoothing the surface by adding a buffer layer, and Ag deposition. To reinforce the interfacial adhesion between the electroplated layers and the 304 tube and increase the area of the Ag coating,a pilger rolling or pilger rolling + heat-treatment process was performed after the Ag electroplating process. Scanningelectron microscopy of the composite tubes after each process indicated that the as-deposited Ag coating changed fromhaving a rough to smooth surface after only pilger rolling and with additional heat treatment. Electron backscatter diffractionanalysis of the microstructures and textures of the tubes revealed that dynamic recrystallization occurred extensively duringpilger rolling, resulting in the formation of a relatively defect-free grain structure without heat treatment. Furthermore,electrochemical polarization curves determined that the Ag-coated composite tubes are superior to the uncoated 304 tubein terms of corrosion resistance under Cl−atmosphere, owing to the formation of a AgCl passivation layer during testing. Surface analysis of the composite tubes suggests that the properties of the AgCl passivation layer are related to the grainsize of the Ag coating and the density of plastic-deformation-induced defects.

Tuberculosis risk is associated with genetic polymorphisms in the LRP2, CUBN, and VDR genes

Sung‑Soo Kim,Sang In Lee,Hyun‑Seok Jin,Sangjung Park 한국유전학회 2020 Genes & Genomics Vol.42 No.10

Background Vitamin D (Vit. D) is used extensively during tuberculosis treatment. Low levels of serum Vit. D increase the risk of active tuberculosis development. Altered expression of the proteins involved in Vit. D metabolism impairs cathelicidin production, thereby increasing the host susceptibility to tuberculosis. Objective We are trying to investigate whether single nucleotide polymorphisms (SNPs) in LRP2, CUBN, and VDR genes could afect tuberculosis development. Methods We included participants of the Korean Association Resource (KARE), part of the Korean Genome and Epidemiology Study (KoGES), and used their recorded data. A total of 8840 people (4182 men and 4658 women) were eligible subjects. The 5-kb regions from the ends of transcripts of GC, LRP2, CUBN, and VDR genes were amplifed to select 13, 47, 70, and 15 SNPs, respectively. For association analysis and statistical analysis, PLINK version 1.07 and PASW Statistics version 18.0 were used. Results Signifcant correlation was observed in 11, 2, and 1 SNPs in LRP2, CUBN, and VDR genes. The efect of rs6747692 of LRP2 on transcription factor binding was confrmed using RegulomeDB. We confrmed that rs2239182 of VDR is located in the genomic eQTL region and can afect transcription factor binding and gene expression. Conclusions Genetic polymorphisms in genes encoding proteins involved in Vit. D metabolism infuence immune system components. Therefore, such polymorphisms may infuence the susceptibility to Mycobacterium tuberculosis invasion and alter the defense mechanisms against Mycobacterium tuberculosis infection. The correlation between genetic variation and tuberculosis development can provide new guidelines for the management of tuberculosis.

골격성 Ⅲ 급 부정교합자의 악골 부조화가 구치부 치성보상에 미치는 영향

성지현,김성식,손우성 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.1

골격성 Ⅲ 급 부정교합자는 부적절한 악골 위치에서 기능 교합을 유지하기 위해 치아의 경사도와 수직적 위치가 변화하게 된다. 이러한 치성보상은 전치부 및 구치부 전반에 걸쳐 일어나며, 현재 보편적으로 시행되고 있는 악교정수술을 위한 술전교정시 이를 제거하여 각 골격 구조내에서 치아들이 적절히 위치되도록 하여야 한다. 전치부 치성보상에 관한 측모 두부방사선 사진을 이용한 연구는 많이 시행되어졌으나, 구치부 경사도에 관한 연구는 미미한 실정이다. 이에 본 연구는 성인 골격성 Ⅲ 급 부정교합자의 전후방적, 수직적 악골 부조화에 따른 폭경 부조화 및 구치 경사도 변화를 알아보기 위해 진단 모형상에서 상하악 견치, 제1소구치, 제1대구치 부위의 기저골 폭경을 측정하여 상악에 대한 하악의 비율을 구하였으며, 모형을 삭제하여 좌우 구치간 경사도를 측정하였다. 악골 부조화 심화에 따른 기저골 폭경 비율과 제1대구치 협설 경사도 변화의 상관관계를 조사하여 다음과 같은 결론을 얻었다. 1. 골격성 Ⅲ 급 부정교합자의 악공의 전후방적 부조화가 심화될수록 상하악 구치간 각도합이 증가하여 치성보상이 많이 일어났으며, 특히 하악 구치가 설측 경사되는 치성보상을 보였다(p<0.001). 2. 골격성 Ⅲ 급 부정교합자의 악골의 수직적 부조화 및 폭경 부조화와 구치부 치성부상 간에는 유의할만한 상관성이 없었다. 3. 골격성 Ⅲ 급 부정교합자의 전후방적, 수직적 부조화의 심화와 기저골 폭경 부조화는 유의할만한 상관성이 없었다. This study examined the relations between degree of posterior dental compensation and skeletal discrepancy in Class Ⅲ malocclusion. The pretreatment lateral cephalograms and dental casts of 87 skeletal Class Ⅲ adults were selected to provide a random sampling of skeletal Class Ⅲ malocclusion. Skeletal discrepancy was described with ANB angle, Wits appraisal, Sn-Mn plane angle, FMA and ratios of basal arch width. Degree of posterior dental compensation was described with macillary intermolar angle, mandibular intermolar angle and sum of intermoloar angle. The relationships between skeletal discrepancy and degree of posterior dental compensation were analyzed with simple correlation analysis, stepwise multiple regression analysis. The results were as follows : 1. A strong association was found between the variation in the anteroposterior measure, ANB angle and the variation of posterior dental compensation measures, sum of intermolar angle and mandibular angle and mandibular intermolar angle in skeletal Class Ⅲ malocclusion. 2. There was no statistically significant relationship between the variation in the vertical measures and the variation of posterior dental compensation measures in skeletal Class Ⅲ malocclusion. 3. There was no statistically significant relationship between the variation in the anteroposterior and vertical measures and degree of basal arch width discrepancy.

조혈모세포이식 환자에서 침습성 진균 감염에 대한 Micafungin의 예방 효과 및 안전성

김시현,이동건,최수미,권재철,박선희,최정현,유진홍,이성은,조병식,김유진,이석,김희제,민창기,조석구,김동욱,이종욱,민우성,박종원 대한감염학회 2010 감염과 화학요법 Vol.42 No.3

Background: Micafungin, a potent inhibitor of 1,3-β-D-glucan synthase, is a novel antifungal agent of the echinocandin class. In vitro study showed that micafungin was effective against Aspergillus species as well as Candida species, but clinical data on the prophylactic efficacy against invasive fungal infections (IFIs) other than candidiasis are still lacking. Materials and Methods: We identified 60 consecutive adult hematopoietic stem cell transplantation (HSCT) recipients who received at least 3 doses of micafungin during neutropenic period. Micafungin was started as an alternative in patients who were intolerant or had adverse events (AEs) to primary prophylactic antifungal agents. We retrospectively reviewed the medical records and analyzed the efficacy and safety of micafungin for prophylaxis against IFIs. Results: The patients either had autologous (n=9) or allogeneic (n=51: 1 syngeneic, 24 sibling, 26 unrelated donor) HSCT. Itraconazole oral solution (n=58) was the most frequently used first line antifungal agent for prophylaxis and was administered for median 11 days. The most frequent cause of switch to micafungin was vomiting (n=42). The duration of neutropenia and micafungin administration was median 13 and 12 days, respectively. A successful outcome was achieved in 45 (75%) patients. Empirical antifungal therapy was initiated in 13 (22%) patients. There were 2 cases (3.3%) of breakthrough fungal infections which comprised a probable invasive pulmonary aspergillosis and a possible invasive fungal sinusitis. There was no case of invasive candidiasis. A total of 53 (88%) patients experienced at least one AE regardless of causality during micafungin administration. The most frequent AEs were hypokalemia, vomiting, diarrhea, and elevated serum aspartate aminotransferase or alanine aminotransferase. Among the aforementioned AEs, only 1 case of diarrhea could be classified as a probable relation with micafungin when causality was assessed. There was no AEs that caused discontinuation of micafungin. Conclusions: Micafungin seems to be a safe and effective agent for prophylaxis of IFIs including aspergillosis as well as candidiasis in HSCT recipients. However, further large, prospective, and randomized comparative studies are warranted for aspergillosis.

The impact of blowflies on pig cadaver decomposition on Yeongdo Island, Busan, South Korea

Park Sang‐Hyun,Baek Seung‐Ho,Moon Tae‐Young 한국곤충학회 2021 Entomological Research Vol.51 No.11

The decomposition process is an important factor in forensics, and flies play a crucial role in the decomposition of animals and humans. However, there remains limited information on the effect of flies that attend death scenes. This study assesses the effect of the presence or absence of blowflies on the rate and process of cadaver decomposition in the spring, summer, and autumn from 2016 to 2020 on Yeongdo Island, Busan, South Korea. Nine blowfly species belonging to four genera in two subfamilies were sampled. The blowflies that approached the cadavers differed between seasons, but Chrysomya pinguis (Walker) was the dominant species regardless of the season. Blowfly presence on cadavers significantly affected the duration of the decomposition stage and the pattern of weight loss in nearly all scenarios. With the presence of blowflies, the decomposition rate was four times faster in spring, three times faster in summer, and nine times faster in autumn. These results show that the presence or absence of blowflies is an essential factor in the decomposition process of cadavers. Therefore, it should be taken into account when estimating postmortem intervals in medicolegal forensic entomology.

하악골에 발생된 Low grade 골육종:증례보고

조현이,정종철,김호성,최재욱,성대경,서지훈,김성범,이계혁 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

Osteosarcoma is a primary malignant tumor arising most often in the long bone, but rare in jaw bone. Especially osteogenic sarcoma of the mandible is a rare tumor, comprising less than 0.5% of all head and neck tumors. Osteosarcoma occurs cheifly in young persons, and presenting very survival rates. Histopathologically this tumor can be classified three types, osteoblastic, fibroblastic, chondroblastic and classified from low grade to high grade by anaplasia or mitosis of the tumor cells. Sometimes, the exact diagnosis of osteosarcoma is difficult especially in low grade osteosarcoma, even if clinical or radiographical findings suggest to osteosarcoma. So suspcious to malignant bone tumor in clinical or radiological findings, biopsy should be taked from deep portion and multiple area, and sharing the patient history and radiographs with pathologist will assist in the development of the diagnosis. We report a case of low grade osteosarcoma on the mandible initially difficulty in accurate diagnosis. The patient visited our hospital for routine dental treatment but radiographic findings displayed ill-defined radiolucency with osteoid formation on the mandible. Final diagnosis was difficulty in initial biopsy but subsequent biopsy taked from deep portion presented infiltrative growth and mitosis of the tumor cell in some area with small osteoid bone formation, so we could reach final diagnosis as low grade sarcoma. We treated this patient with bloc resection of the mandible and immediate reconstruction with iliac corticocancellous block.

Consistency of seasonal patterns of insect succession on pig cadavers at Yeongdo Island in Busan, Korea

Park Sang‐Hyun,Moon Tae‐Young 한국곤충학회 2021 Entomological Research Vol.51 No.1

Cadaver insects cause dead bodies to break down in ecological processes. Still, the knowledge has been accumulated slowly about the structure and role of the insect assemblages attending to death scenes. This study analysed the successional patterns of insects on pig cadavers in the spring, summer, and autumn from 2016 to 2019 at Yeongdo Island, Busan, South Korea. A sum of 71 insect species belonging to four orders and 21 families were sampled. Predominant insects were largely Diptera and Coleoptera. The majority of the flies were the calliphorids as Chrysomya pinguis (Walker) and Lucilia porphyrina (Walker). The most common beetles were Creophilus maxillosus (L.), Omosita japonica (Reitter), and Staphylinidae sp. regardless of seasons. Occurrence matrices were made from the successional patterns of insect species during 42 sampling intervals in the spring, 38 sampling intervals in the summer, and 26 sampling intervals in the autumn. Permutation analyses of the occurrence matrices showed that the patterns of succession were similar between spring 2016 and 2017 (P = 0.019), between summer 2016 and 2017 (P = 0.003), and between autumn 2016 and 2019 (P = 0.002). The result shows that there are clear patterns in succession between seasons, and provides the reference data to presume the death time, at least in the southeast part of South Korea.

Distribution and mitochondrial DNA tracing of the invasive Argentine ants (Linepithema humile) in South Korea

Park Sang‐Hyun,Ha Young‐Ho,Kim Dong Eon,Kim Chang‐Jun,Choi Moon Bo 한국곤충학회 2021 Entomological Research Vol.51 No.3

Argentine ants (Linepithema humile) are one of the world’s most invasive species and were first reported in South Korea, near Busan Port in 2019. The distribution of their initial spread was investigated here from April to July 2020. In the invasion area, numerous nests and individuals were identified, indicating that they had settled and successfully invaded the habitat. To track the invasion of the Argentine ants we conducted haplotype analysis using COI, COII, and Cytb sequences of their mitochondrial DNA. The invasive ants had the same mitochondrial haplotype (H3) as Argentine ants from America (Chile, Ecuador, Bermuda) and East Asia (Japan). When comparing the import trade volumes at Busan port with the Argentine ant haplotypes from other countries, it was determined that the invasive ants may have originated from the United States or Japan. Numerous ecological and economic impacts due to their invasion and spread in other countries has previously been reported. Therefore, prompt control measures for the Argentine ants found at Busan port, at this relatively early stage of settlement, is required.

비외상성 두개내 출혈 환자에서 심근손상의 발생과 예후에 미치는 영향

강구현,황성호,이강현,조준휘,김성환,문중범,박해상,이서영,이성수,김헌주 대한응급의학회 2000 대한응급의학회지 Vol.11 No.4

Objective: The aim of this study was to investigate the clinical significance of myocardial injuries in patients with nontraumatic intracranial hemorrhage by identifying the occurrence of myocardial injury and defining its correlation with subsequent cardiovascular events. Subjects and methods: One hundred twenty-four patients with nontraumatic intracraninal hemorrhage presented to the emergency department within six hours from onset of symptoms were enrolled. Brain CT, serial electrocardiography, and echocardiography were done at the emergency center. Blood samples for troponin I and creatine kinase(CK)-MB were drawn immediately and eight hours after admission, Troponin I and CK-MB were measured using a chemiluminescent immunoassay, respectively. Results: Electrocardiographic and echocardiography abnormalities were found in 65 cases(52.4%) and 21 cases(17%), respectively. Serum troponin I and creative kinase-MB were increased in 35 cases (28.2%) and in 58 cases(46.8%), respectively. Abnormal findings of echocardiography and ECG, as well as elevated levels of serum troponin I and creative kinase-MB, were associated with an increased risk of cardiovascular event and survival. Logistic regression analysis revealed that an abnormal echcocardiographic finding and elevation of serum troponin I were factors associated with the occurrence an adverse cardiovascular event and that electrocardiographic abnormalities and initial mental status were factors associated with poor prognosis. Conclusion: This study reveals that actual myocardial injury develops in a significant proportion of patients with nontraumatic intracranial hemorrhage and that the development of the myocardial injury is associated with an adverse cardiovascular event that occurs during admission.

중년 여성에서 발생한 집합관 신세포암 1 예

황인성;정재현;유지형;성락희;노충희;정재용;김현정 인제대학교 2011 仁濟醫學 Vol.32 No.-

Collecting duct renal cell carcinoma (CDRCC) or Bellini duct carcinoma is a rare type of renal cell carcinoma (RCC), accounting for 0.4% to 1.8% of all RCC. CDRCC is considered to originate from the collecting duct of the kidney and it has a poor prognosis. However, the clinical features of CDRCC remain poorly understood, mainly because only studies with a small series or case reports have been published to date. We experienced a case of CDRCC of kidney.