Improved photothermal, photodynamic and photoacoustic effect of rGO/AuNR hybrid composite system

이승화,김소연 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Over the past few decades, photothermal therapy(PTT) has been studied intensively in the biomedical applications. Although there are various gold nanostructures, especially gold nanorods(AuNRs) have been selected as photothermal agents due to their high photothermal conversion efficiencies and simple synthesis procedure. However, there are some limitations that the targeting ability to cancer cells is poor and photothermal conversion efficiencies are lower than recent other hybrid systems. So we prepared the reduced graphene oxide (rGO)/AuNR habrid composite containing tumor targeting ligand FA and photosensitizer. We determined the physicochemical properties of rGO/AuNR hybrid composites. In addition, we investigated their photoacoustic effect as well as synergistic PDT/PTT effect.

A Case of Endoscopic Resection of a Colonic Semipedunculated Leiomyoma

이승화,허건웅,정유석 대한대장항문학회 2011 Annals of Coloproctolgy Vol.27 No.4

During colonoscopic examination, epithelial lesions, such as adenomatous polyps, are frequently encountered, unlike sub- epithelial lesions, such as leiomyomas, which are uncommon. A colonic leiomyoma is a rare tumor, originating either from the mucularis mucosa or from the proper muscle, and accounts for only 3% of all gastrointestinal leiomyomas. Colonic leio- myomas are usually benign and asymptomatic. However, they can sometimes cause symptoms, ie, abdominal pain, intesti- nal obstruction, hemorrhage, and perforation. The traditional management option for a colonic leiomyoma is surgical re- section. Recently, with the development of endoscopy devices and techniques, the endoscopic resection has been consid- ered as an alternative treatment option. We experienced a patient with a leiomyoma that was diagnosed during colonoscopy. The leiomyoma was resected endoscopically without complication. We report this case with a review of the literature.

The Performance Investigation of Bimodal Cation Exchange/Hydrophilic Interaction Liquid Chromatography–Electrospray Ionization Mass Spectrometry by Modifying Mobile Phase Composition in Amino Acid Separation

이승화,김희원,한상문,한상윤,김병주,문명희,김기훈,이재익 대한화학회 2019 Bulletin of the Korean Chemical Society Vol.40 No.8

Owing to its unique selectivity, mixed-mode chromatography (MMC) has been extended to the analysis of biological fluids. Among various MMC applications, ion exchange/hydrophilic interaction liquid chromatography (IEX/HILIC) is particularly beneficial for the analysis of polar compounds without derivatization or ion pairing. Nevertheless, no practical information about the retention behavior is discussed. In this study, the chromatographic behavior of amino acids in a CEX/hydrophilic interaction mixed-mode column via the modification of the mobile phase was investigated. A low buffer salt concentration led to increased retention; particularly, positively charged amino acids were not eluted by excessive interactions with the negatively charged stationary phase at a moderate salt concentration (<20 mM). An acid modifier of formic acid or acetic acid exhibited a similar effect on the separation, and a low acid concentration (<0.5%) led to peak broadening by additional ion exchange with a silanol group at high pH. With respect to the composition of organic solvents, aprotic solvents such as tetrahydrofuran or acetonitrile afforded appropriate retention. However, protic solvents led to the considerably reduced retention except positively charged amino acids. Novel, practical information for the optimization or development of applications with a CEX/HILIC column for polar analytes such as amino acids was obtained.

중환자실에 입원한 세균성 폐렴환자에서 반정량적 procalcitonin 검사의 유용성

이승화,김지연,현인규,우흥정,김현수,김철홍,박선욱,김용욱 대한감염학회 2009 Infection and Chemotherapy Vol.41 No.6

Background:In pulmonary infection, serum procalcitonin levels increase rapidly, probably in response to sepsis-related cytokine release from neuroendocrine cells of bronchial epithelium and inflammatory cells. We applied procalcitonin assay in critically ill patients with bacterial pneumonia. Materials and Methods:Patients admitted to the intensive care unit (ICU) and show diffuse infiltrations in their chest X-ray were included. Quantitative bronchoalveolar lavage (BAL) culture (≥104 CFU/mL) was performed in all cases on the 5th day of ICU admission. We excluded patients with structural lung disease, non-infectious lung infiltrations, and atypical infections such as Mycobacterium tuberculosis, Pneumocystis jiroveci, and viruses. Serum procalcitonin levels were measured semi-quantitatively by using PCT-Q kit. Results:A total of 28 adult patients (M:F=23:5) were included: 11 (39.3%) medically-ill patients, 7 (25%) surgically-ill patients, and 10 (35.7%) burn patients. Serum procalcitonin level was <0.5 ng/mL in half of the cases (14/28) and ≥0.5 ng/mL in the remaining half of the cases. Compared to those with serum procalcitonin level of <0.5 ng/mL, patients with serum procalcitonin level of ≥0.5 ng/mL had more frequent mechanical ventilation, higher CRP/APACHE II scores/number of organ failure (P<0.05), and showed increased tendency for death (P=0.052). Positive bacterial BAL cultures were noted in 17 cases (60.7%). Of these, 7 cases (41.2%) showed serum procalcitonin level ≥0.5 ng/mL. Conclusions:High serum procalcitonin level seems to be closely associated with the severity and poor prognosis in critically ill patients with bacterial pneumonia. However, pneumonia could not be excluded with low level of procalcitonin among ICU patients. Background:In pulmonary infection, serum procalcitonin levels increase rapidly, probably in response to sepsis-related cytokine release from neuroendocrine cells of bronchial epithelium and inflammatory cells. We applied procalcitonin assay in critically ill patients with bacterial pneumonia. Materials and Methods:Patients admitted to the intensive care unit (ICU) and show diffuse infiltrations in their chest X-ray were included. Quantitative bronchoalveolar lavage (BAL) culture (≥104 CFU/mL) was performed in all cases on the 5th day of ICU admission. We excluded patients with structural lung disease, non-infectious lung infiltrations, and atypical infections such as Mycobacterium tuberculosis, Pneumocystis jiroveci, and viruses. Serum procalcitonin levels were measured semi-quantitatively by using PCT-Q kit. Results:A total of 28 adult patients (M:F=23:5) were included: 11 (39.3%) medically-ill patients, 7 (25%) surgically-ill patients, and 10 (35.7%) burn patients. Serum procalcitonin level was <0.5 ng/mL in half of the cases (14/28) and ≥0.5 ng/mL in the remaining half of the cases. Compared to those with serum procalcitonin level of <0.5 ng/mL, patients with serum procalcitonin level of ≥0.5 ng/mL had more frequent mechanical ventilation, higher CRP/APACHE II scores/number of organ failure (P<0.05), and showed increased tendency for death (P=0.052). Positive bacterial BAL cultures were noted in 17 cases (60.7%). Of these, 7 cases (41.2%) showed serum procalcitonin level ≥0.5 ng/mL. Conclusions:High serum procalcitonin level seems to be closely associated with the severity and poor prognosis in critically ill patients with bacterial pneumonia. However, pneumonia could not be excluded with low level of procalcitonin among ICU patients.

캠핑 트렌드 변화에 따른 미니멀 캠핑족의 캠핑장비 사용행태 연구

이승화,선섭희 사단법인 한국조형디자인협회 2023 조형디자인연구 Vol.26 No.4

As the culture of Work-Life Balance gains traction, camping has emerged as a trendy leisure activity, giving rise to various camping styles. Notably, the growing trend of "solo economy" and individualization has led to the popularity of "minimalist camping," where 1-2 individuals enjoy camping with essential gear. Although active development targeting this consumer group is underway, there has been a lack of preliminary research on new equipment. Accordingly, this study aims to identify the current equipment preferences and usage behaviors of minimalist campers to forecast emerging equipment and features. The study initiated with a detailed compilation of camping equipment lists, spanning from the 1980s to the present, segmented into decade intervals. This comprehensive list was then refined and utilized to conduct a survey among minimal camping enthusiasts. The survey focused on verifying the equipment actually owned by these campers against the pre-established list. This process helped in accurately determining the gear they possess and use during camping. The list of camping equipment was then finalized based on these findings. Following this, observational studies were conducted targeting the finalized equipment list. These studies aimed at understanding the usage patterns of the equipment. The research further delved into identifying possible improvements for each piece of equipment and exploring new functional elements. In addition, it focused on uncovering latent needs and pain points of the campers, paving the way for the development of new camping gear. The results of this research are expected to serve as a foundational resource for future research and development in the field of camping equipment.

곤충병원선충(Steinernema carpocapsae Weiser)의 냉동저장법

이승화,김용균,한상찬 한국응용곤충학회 2000 한국응용곤충학회지 Vol.39 No.3

Cryopreservation of infective juveniles of entomopathogenic nematode, Steinernema carpocapsae Weiser, was conducted at $-190^{\circ}C$ liquid nitrogen and its, efficacy was analysed on nematode survival and pathogenicity with glycerol pretreatments and storage periods. Infective juveniles were pre-treated before being frozen by incubating the nematodes in 22% glycerol for each of 6, 12, and 24 h, followed by 70% methanol at $0^{\circ}C$ for 10 minutes. Just after glycerol and methanol incubations, subsamp1es of the nematodes were resuspended in 0.85% saline and maintained during 24h for viability determination. Different glycerol incubation periods significantly affected the nematode susceptibility to methanol infiltration. Six hour incubation in glycerol resulted in much less nematode survival than did 12 h or 24 h incubation. About 70% of the infective juveniles frozen at $-190^{\circ}C$ for 5 months, preincubat-ed in glycerol at least for 12h, were able to survive after being resuspended in 30°C saline. They did not also show any change in their pathogenicity during cryopreservation. These results suggest an improved technique for long-term storage of the entomopathogenic nematodes. 곤충변원성충(Steinernema carpocapsae Weiser)의 감염태 유충에 대한 액체질소( $-190^{\circ}C$)냉동 저장하는 방법을 개발하기 위하여, 냉동보관 전처리 과정 및 저장기간에 따른 선충생존율과 감염력 변이를 조사하였다. 냉동저장 전에 22% 글리세롤로 선충은 6, 12, 24시간 동안 배양한 후 70% methanol($0^{\circ}C$)안에 10분간 유지하였다. 글리세롤과 methanol에 넣어 둔 샘플을 0,85% 식염수에 넣어 24시간 유지한 후 생존능력을 측정하였다. 글리세롤 배양시간에 따른 선충 생존율의 차이는 없었으나, methanol처리에서는 글리세롤 처리 시간이 길수록 선충 생존율이 높게 나타났다. 냉동저장에 따른 선충의 생존율은 글리세롤 배양시간이 짧았던 처리(6시간)를 제외하고는 5개월 동안 평균 70% 이상으로 높게 나타났다. 냉동저장 되었던 선충의 곤충감염율은 저장기간에 관계없이 90% 이상을 나타내었다. 이상의 결과는 곤충병원선충이 냉동저장에 의해 장기간보존이 가능하다는 것을 제시한다.

Comparison of the Efficacy and Safety of Sodium Phosphate Tablets and Polyethylene Glycol Solution for Bowel Cleansing in Healthy Korean Adults

이승화,이득주,김광민,서상욱,강준구,이은혜,이동률 연세대학교의과대학 2014 Yonsei medical journal Vol.55 No.6

Purpose: Bowel cleansing is generally regarded as time-consuming and unpleasantamong patients. Patients commonly state that bowel preparation provokes more discomfort than the actual colonoscopic examination. The purpose of this study was to compare two regimens of sodium phosphate (NaP) tablets versus polyethylene glycol (PEG) solution for bowel preparation in healthy Korean adults. Materials and Methods: This was a single center, prospective, open-label, investigator-blinded, randomized, controlled-pilot study. A total of 62 healthy Koreansubjects were randomly assigned to two groups (NaP vs. PEG). Efficacy, safety, and patient-related outcomes, as well as procedural parameters, were evaluated. Results: Although there were no significant differences in total Ottawa bowelquality score, fluid scores and the rate of adequate bowel preparation were significantlybetter in the NaP group than the PEG group. Additionally, the NaP group showed better results regarding patient tolerance, satisfaction, preference, and rate of adverse events than the PEG group. Significant fluctuations in specific serum electrolytes were common and of a greater magnitude in the NaP group than the PEG group. However, these abnormalities were transient and did not result in seriouscomplications and side effects. Conclusion: In this study, NaP tablets were shown to be an effective, well-tolerated, and acceptable regimen for bowel preparation. Also, our study suggests that NaP tablets may be safe and can be used as a bowel cleansing agent in healthy adults undergoing elective colonoscopy. Further multicenter, large scale studies are needed to confirm these findings.

코로나바이러스감염증-19 예방접종

이승화,안상현,김봉영,이재혁,김대현 계명대학교 의과대학 2021 계명의대학술지 Vol.40 No.2

Coronavirus disease 2019 (COVID-19) vaccination is necessary to prevent infection, morbidity, and mortality. In addition to the usual post-inoculation hypersensitivity reactions including headaches, muscle and joint pain, and fever, especially after the second shot, the mRNA vaccine has risk of inflammation in the heart and heart lining of some recipients, mostly younger people. And the adenovirus vector vaccine can induce rare immune thrombocytopenia. Vaccination should be encouraged according to the information about the effectiveness and safety in individual situation

중환자실에 입원한 세균성 폐렴환자에서 반정량적 procalcitonin 검사의 유용성

이승화,김철홍,김지연,박선욱,김용욱,현인규,우흥정,김현수 대한감염학회 2009 감염과 화학요법 Vol.41 No.6

Background : In pulmonary infection, serum procalcitonin levels increase rapidly, probably in response to sepsis-related cytokine release from neuroendocrine cells of bronchial epithelium and inflammatory cells. We applied procalcitonin assay in critically ill patients with bacterial pneumonia. Materials and Methods : Patients admitted to the intensive care unit (ICU) and show diffuse infiltrations in their chest X-ray were included. Quantitative bronchoalveolar lavage (BAL) culture (≥10⁴ CFU/mL) was performed in all cases on the 5^(th) day of ICU admission. We excluded patients with structural lung disease, non-infectious lung infiltrations, and atypical infections such as Mycobacterium tuberculosis, Pneumocystis jiroveci, and viruses. Serum procalcitonin levels were measured semi-quantitatively by using PCT-Q kit. Results : A total of 28 adult patients (M:F=23:5) were included: 11 (39.3%) medically-ill patients, 7 (25%) surgically-ill patients, and 10 (35.7%) burn patients. Serum procalcitonin level was <0.5 ng/mL in half of the cases (14/28) and ≥0.5 ng/mL in the remaining half of the cases. Compared to those with serum procalcitonin level of <0.5 ng/mL, patients with serum procalcitonin level of ≥0.5 ng/mL had more frequent mechanical ventilation, higher CRP/APACHE II scores/number of organ failure (P<0.05), and showed increased tendency for death (P=0.052). Positive bacterial BAL cultures were noted in 17 cases (60.7%). Of these, 7 cases (41.2%) showed serum procalcitonin level ≥0.5 ng/mL. Conclusions : High serum procalcitonin level seems to be closely associated with the severity and poor prognosis in critically ill patients with bacterial pneumonia. However, pneumonia could not be excluded with low level of procalcitonin among ICU patients.

2007년 개정 교육과정에 따른 한국 과학교과서와 미국 과학교과서의 삽화 비교 연구

이승화,김용권 대한지구과학교육학회 2012 대한지구과학교육학회지 Vol.5 No.1

The focus of this study was on the comparative analysis in the area of illustrations between the primary school from third grade to the sixth grade between Korean and American science textbooks in order to offer some suggestions for consideration of the Korean science textbooks, which will be revised in 2009. The results are as follows: The number of illustrations per page in Korean science textbooks are more than that of American science textbooks. As the type of illustrations, the ratio of photos is the highest and as the role of illustrations, data provision has the highest percentage in both countries. The motivation role in Korean science textbooks seem to be higher than American science textbook, whereas study summary role is more prominent in American textbooks than in Korean textbooks.