A pattern of cell death induced by 40 kHz ultrasound in yeast cell model

김지욱,공희정,김영환,강광일,Kim, Ji Wook,Kong, Hee Jeong,Kim, Young H.,Kang, Kwang Il The Acoustical Society of Korea 2017 韓國音響學會誌 Vol.36 No.3

초음파는 세포사멸을 포함하여 의학 및 생물학분야에 널리 응용되고 있으나 그 정확한 기작에 대해선 논쟁의 여지가 있다. 본 연구에서는 40 kH 초음파 조사시스템을 단세포 효모에 적합하게 개발하고 세포사멸 유도시 40 kH 초음파의 생물학적 현상을 살펴보았다. 아이오딘화 칼륨 선량 측정법을 이용하여 1.5 ml 실험튜브에 40 kH 초음파 조사 시스템의 최적 조건을 맞추어 세포사멸을 시간 의존적 방식으로 연구하였고 초음파 조사과정동안 온열효과와는 별개로 세포 사멸이 관찰되었다. 40 kH 초음파와 과산화수소의 동시 처리는 세포사멸에 상조적인 효과가 관찰되어 활성산소가 40 kH 초음파사멸에 관련이 있었다. 그러나 활성산소 저해제, NAC(N-acetyl-Lcysteine)는 초음파에 의한 세포사멸에 약한 영향만을 미쳤고 다른 세포사멸, 괴사억제제[글리실리진(glycyrrhizin) 또는 zVAD-fmk] 역시도 세포사멸을 완전히 억제하진 못하였다. 본 연구를 통하여 40 kH 초음파에 의한 세포사멸에는 온열효과나 활성산소만으로 사멸이 유도되지는 않는 것으로 보인다. Ultrasound has been widely used for biological and medical applications including induction of cell death, but a precise mechanism of induced cell death by ultrasound is controversial. In this study, an irradiation system with 40 kHz ultrasound was developed for a suitable cell death test of a representative unicellular organism, yeast, and used to study the biological effect of ultrasound on inducing cell death. Potassium Iodide (KI) dosimetry was used to devise an optimal system that successfully delivers 40 kHz ultrasound and produces reactive oxygen species in a 1.5 ml Eppendorf tube. Cell death was observed in an ultrasound transmission time-dependent fashion in this system. Thermal effect during irradiation was not observable in ultrasound induced cell death. Co-treatment of 40 kHz ultrasound and hydrogen peroxide showed a synergistic effect in inducing cell death. This finding suggests that 40 kHz ultrasound is related to reactive oxygen species formation. However, NAC (N-acetyl-L-cysteine) oxygen scavenger slightly inhibited the cell death by 40 kHz ultrasound. It was also found that 40 kHz ultrasound induced cell death was slightly inhibited by inhibitors of necrosis or apoptosis (glycyrrhizin or zVAD-fmk). This study suggests that cell death induced by 40 kHz ultrasound may not be exclusively related to reactive oxygen species formation and thermal effects in irradiated yeast cells.

지하수 모델링을 통한 지하수댐 건설 효과 분석

김지욱,임경남,박현진,이보경,Kim, Ji-Wook,Lim, Kyung-Nam,Park, Hyun-Jin,Rhee, Bo-Kyoung 한국지하수토양환경학회 2013 지하수토양환경 Vol.18 No.3

SEAWAT, a linked modeling program of Visual MODFLOW was used to analyze the change in groundwater levels and salinity related groundwater dam construction in Cheongsan island, Wando-Gun, Jeollanam-Do. The steady-state model results show the groundwater flow and salinity distribution of the studied area. The groundwater flows from north-west and south-east highlands into the river, located in the middle part of the basin, and is eventually discharged to the ocean. Part of the sea water infiltrates into the river; and through the estuary's alluvium aquifer, the sea water intrusion takes place spreading to about 830 m from the ocean. The transient model results show that after the groundwater dam construction, groundwater levels will rise to a maximum of 2.0 m upstream, and the groundwater storage will increase 21,000 after 10 years. Meanwhile 31% of the total area affected by sea water intrusion will decrease. To conclude, the groundwater dam is a very useful method for a secure water resource in preparation for drought and water shortages in the island regions.

제주도 지하수 관리수위 설정에 관한 연구

김지욱,고기원,원종호,한찬,Kim Ji-Wook,Koh Gi-Won,Won Jong-Ho,Han Chan 한국지하수토양환경학회 2005 지하수토양환경 Vol.10 No.2

제주도는 우리나라 최다우지역에 속하지만 강우량의 편차가 심하여 이에 따른 년간 지히수 함양량과 적정개발량이 큰 차이를 보이고 있다. 이에 제주도에서는 이상 가뭄이 지속시 해수침투, 지하수위 강하 등의 장해를 예방하기 위하여 대표적인 지하수 관측정의 수위를 기준으로 수위 강하에 따른 적절한 조치를 취할 수 있도록 지하수 관리제도를 도입하였다. 본 연구에서는 이상 가뭄이 지속시 지하수 자원의 적절한 관리를 위해 강우량과 지하수위 관측자료의 분석을 통해 지하수위 강하에 따른 단계별 제한 조치를 취할 수 있는 지하수 관리수위를 제시하였다 우선, 제준 도의 30년간 강우자료를 대상으로 99% 신뢰구간의 하한값을 각 유역별 기준 강우량으로 설정하였으며, 기준 강우량 이하의 강우가 3개월 이상 지속된 기간의 지하수위 관측자료를 추출하였다. 이와 같이 추출된 지하수위 관측자료의 99% 신뢰구간의 하한값을 기준 지하수위로 설정하고, 기준 지하수위의 일정비율을 단계별 지하수 관리수위로 제시하였다. Jeju island is one of the highest rainfall areas in the Korean peninsular. However, variation in rainfall amount is much great with years, which resulted in substantial variation in annual groundwater recharge and sustainable yield. Therefore, to cope with groundwater hazard including sea water intrusion and water level decline in accordance with successive extreme drought, Jeju province established a stepwise action system, in which management of representative monitoring wells and corresponding actions to water level conditions was enforced. In this study, rainfall and groundwater monitoring data were analyzed to determine management groundwater level on Jeju island. First, rainfall data for last 30 years were analyzed, which yielded a lower limit of rainfall at a confidence level of 99% as a basis rainfall. Only when the rainfall less than the basis rainfall was sustained over 3 months, the water levels were targeted for the analysis. For the water level data selected using the above criteria, the lower limit of 99% confidence interval was determined as a reference groundwater level. Finally, some ratios of reference groundwater level was determined as stepwise management groundwater level on Jeju island.

망막분지정맥폐쇄에 합병된 황반부종에서 유리체강내 베바시주맙 주입술이 삶의 질에 미치는 영향

김지욱,최경식,이미리,이성진,Jee Wook Kim,MD,Kyung Seek Choi,MD,PhD,Mi Ri Rhee,MD,Sung Jin Lee,MD,PhD 대한안과학회 2012 대한안과학회지 Vol.53 No.10

Purpose: To evaluate the impact of intravitreal bevacizumab injection on visual function and vision-related quality of life (VR-QOL) in patients with branch retinal vein occlusion (BRVO) using the Korean version of the National Eye Institute Visual Function Questionnaire 25 (K-NEI-VFQ-25). Methods: This study included 32 normal control subjects and 32 patients with BRVO. The Korean version of NEI-VFQ-25 was answered by the patients with BRVO before and 3 months after intravitreal bevacizumab injection, as well as by normal control subjects. Clinical data were collected, including central macular thickness (CMT), total macular volume (TMV) (using time-domain optical coherence tomography [OCT]), and best corrected visual acuity (BCVA). Results: Visual acuity, CMT, and TMV significantly improved 3 months after intravitreal bevacizumab injections. No bevacizumab- related systemic or ocular adverse effects following intravitreal drug injections were observed. Significant improvement in the VFQ-25 composite score was observed in patients with BRVO. Subscale scores, including general vision, near activities, distance activities, social functioning, mental health, role difficulties, dependency, and peripheral vision, improved after injection. However, subscale scores regarding general health, ocular pain, driving, and color vision did not improve significantly. Conclusions: Intravitreal bevacizumab injection appears to be an effective treatment for visual function, as well as VR-QOL in macular edema secondary to BRVO. However, improvement of driving function and color vision appears to require a longer recovery time than visual function. J Korean Ophthalmol Soc 2012;53(10):1465-1471

가계의 쓰레기 재활용시간 결정요인 분석 ( 경제학문헌목록 주제분류 : R2 , Q2 )

김지욱,정의철 ( Ji Uk Kim,Eui Chul Chung ) 한국경제학회 1998 經濟學硏究 Vol.46 No.1

Comparison of bolus administration effects of lidocaine on preventing tourniquet-induced hypertension in patients undergoing general anesthesia: a randomized controlled trial

김지욱,Lee A Ran,Park Eun Sun,Yun Minsu,Ryu Sung Won,Kim Uk Gwan,강동희,Kim Ju Deok 대한마취통증의학회 2022 Anesthesia and pain medicine Vol.17 No.1

Background: This study assessed the effect of a single bolus administration of lidocaine on the prevention of tourniquet-induced hypertension (TIH) and compared the effect of lidocaine to that of ketamine in patients undergoing general anesthesia.Methods: This randomized, controlled, double-blind study included 75 patients who underwent lower limb surgery using a tourniquet. The patients were administered lidocaine (1.5 mg/kg, n = 25), ketamine (0.2 mg/kg, n = 25) or placebo (n = 25). The study drugs were administered intravenously 10 min before tourniquet inflation. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before tourniquet inflation, after tourniquet inflation for 60 min at 10 min intervals, and immediately after tourniquet deflation. The incidence of TIH, defined as an increase of 30% or more in SBP or DBP during tourniquet inflation, was also recorded.Results: SBP, DBP, and HR increased significantly over time in the control group compared to those in the lidocaine and ketamine groups for 60 min after tourniquet inflation (P < 0.001, P < 0.001, and P = 0.007, respectively). The incidence of TIH was significantly lower in the lidocaine (n = 4, 16%) and ketamine (n = 3, 12%) group than in the control group (n = 14, 56%) (P = 0.001). Conclusion: Single-bolus lidocaine effectively attenuated blood pressure increase due to tourniquet inflation, with an effect comparable to that of bolus ketamine.

경기도 지역축제의 현황과 특징

김지욱,Kim, Ji-Uk 국립문화재연구원 1995 헤리티지:역사와 과학 Vol.28 No.-

Change of inspired oxygen concentration in low flow anesthesia

김지욱,Kang Donghee,Lee Hochul,Ryu Sungwon,Ryu Siejeong,Kim Doosik 대한마취통증의학회 2020 Anesthesia and pain medicine Vol.15 No.4

Background: There are several advantages of low flow anesthesia including safety, economics, and eco-friendliness. However, oxygen concentration of fresh gas flow and inspired gas are large different in low flow anesthesia. This is a hurdle to access to low flow anesthesia. In this study, we aimed to investigate the change in inhaled oxygen concentration in low flow anesthesia using oxygen and medical air.Methods: A total of 60 patients scheduled for elective surgery with an American Society of Anesthesiologist physical status I or II were enrolled and randomly allocated into two groups. Group H: Fresh gas flow rate (FGF) 4 L/min (FiO₂ 0.5). Group L: FGF 1 L/min (FiO₂ 0.5). FGF was applied 4 L/min in initial phase (10 min) after intubation. After initial phase FGF was adjusted according to groups. FGF continued at the end of surgery. Oxygen and inhalation anesthetic gas concentration were recorded for 180 min at 15 min interval.Results: The inspired oxygen concentration decreased by 5.5% during the first 15 min in the group L. Inspired oxygen decreased by 1.5% during next 15 min. Inspired oxygen decreased by 1.4% for 30 to 60 min. The inspired oxygen of group L is 35.4 ± 4.0% in 180 min. The group H had little difference in inspired oxygen concentration over time and decreased by 1.8% for 180 min.Conclusions: The inspired oxygen concentration is maintained at 30% or more for 180 min in patients under 90 kg. Despite some technical difficulties, low flow anesthesia may be considered.

Alcohol and Cognition in the Elderly: A Review

김지욱,이동영,이병철,정명훈,Hano Kim,Yong Sung Choi,최인근 대한신경정신의학회 2012 PSYCHIATRY INVESTIGATION Vol.9 No.1

Consumption of large amounts of alcohol is known to have negative effects, but consumption in smaller amounts may be protective. The effect of alcohol may be greater in the elderly than in younger adults, particularly with regard to cognition. However, the drinking pattern that will provide optimal protection against dementia and cognitive decline in the elderly has not been systematically investigated. The present paper is a critical review of research on the effect of alcohol on cognitive function and dementia in the elderly. Studies published from 1971 to 2011 related to alcohol and cognition in the elderly were reviewed using a PubMed search. Alcohol may have both a neurotoxic and neuroprotective effect. Longitudinal and brain imaging studies in the elderly show that excessive alcohol consumption may increase the risk of cognitive dysfunction and dementia, but low to moderate alcohol intake may protect against cognitive decline and dementia and provide cardiovascular benefits. Evidence suggesting that low to moderate alcohol consumption in the elderly protects against cognitive decline and dementia exists; however, because of varying methodology and a lack of standardized definitions, these findings should be interpreted with caution. It is important to conduct more, well-designed studies to identify the alcohol drinking pattern that will optimally protect the elderly against cognitive decline and dementia.

가공치즈와 구성 성분

김지욱,Kim, Jiuk 한국축산식품학회 2016 축산식품과학과 산업 Vol.5 No.1