정량적관상동맥조영술의 정확도 및 재현도

조용근,황진용,박헌식,채성철,전재은,박의현 慶北大學校 醫科大學 1996 慶北醫大誌 Vol.37 No.4

목적 : 정량적관상동맥조영술이 최근 널리 보급되고 있지만 국내외를 막론하고 이의 정확도 및 재현도에 관한 연구가 불충분하여 본 연구를 하였다. 대상 및 방법 : 110명의 환자에서 미국 General Electric사의 Advantx L/C/LP 디지탈혈관찰영기와 미국 USCI사의 좌관상동맥용 Judkins형의 Pro-Flo XT^(TM) 6F 도자를 이용하여 좌관상동맥조영술을 같은 각도에서 3회 실시하고 도자의 외경을 일본 Mitutoyo사의 정밀도 0.01㎜의 micrometer로 측정한 후 측정된 도자의 실제 직경과 정량적관상동맥조영술로 측정된 관상동맥의 직경을 비교하였다. 결 과 : USCI® Pro-Flo XT^(TM) 6F 좌관상동맥용 도자의 실제 외경은 1.91±0.03㎜이었고 정량적관상동맥조영술로 측정 한 도자의 외경은 1.94±0.11㎜이었다. 도자를 5.7F로 calibration했을 매 도자의 외경은 1.87±0.12㎜이었다. 세번 다 다른 화상에서 측정한 경우 근위부관상동맥 직경의 차이는 0.02±0.12㎜이었고 같은 화상에서 3회 측정하였던 경우에는 0.11±0.01㎜이었다. 결론 : 정량적관상동맥조영술의 정확도 및 재현도는 사용에 적합한 정도이나 적지 않은 문제점에 대한 보완이 필요하다고 생각된다. During quantitaive coronary angiography(QCA), contrast filled catheter is usually used as a scaling device. However the real diamerer of catheter is almost always smaller than the listed diameter. We measured the real diameter of catheters with precision micrometer(Mitutoyo® Japan). After caliberating the catheter as listed French size and diameter, we did QCA at the same tube position of the diameters of catheter and proximal left coronary artery. All measurements were done 3 times consecutively. The mean real diameter of USCI® Pro-Flo XT^(TM) 6 F left Judkin catheter was 1.91±0.03 ㎜. The mean QCA diamter of the same catheter was 1.94±0.11 ㎜. When we calibrated catheter as 1.91 ㎜. the mean QCA diameter was 1.87±0.12 ㎜. The mean differences of the diameters of the proximal left coronary artery were 0.20±0.12 ㎜ when the measurements were done in three different frames. When the measurements were done in the same frmae, the mean difference decreased to 0.11±0.01 ㎜. We conclude that the precision and reproducibility of QCA are within reasonable range, but more refimement is needed.

과량의 인슐린 투여로 인한 인위성 저혈당증 1예

김준우,안철우,남주영,김똘미,김영균,추적금,박종숙,박진아,조승현,김동연,김도연,윤수지,이경열,차봉수,김경래,임승길,이현철,허갑범 대한당뇨병학회 2002 임상당뇨병 Vol.3 No.2

본 저자들은 인위적인 인슐린 투여로 인한 인간성 저혈당증 1예에서 보존적인 치료로 의식기능은 회복하였으나, 현저한 인지능력 저하를 하였기에 문헌고찰과 함께 보고하는 바이다. Factitious hypoglycemia is a covert attempt to lower the blood glucose concentration with insulin or a sulfonylurea agent. This attempt is mainly performed by the patients themselves. In a large series of diabetics who had overdosed on drug, less than 5% had used insulin for suicidal or homicidal purposes. Additionally, 4 of 204 hypoglycemic episodes were due to a suicide attempt with insulin. The onset of insulin action, its peak level, and duration, and the degree of hypoglycemia, are determined by insulin's pharmacokinetics. However, the final outcomes are not associated with the amount of insulin used. The complications related to insulin overdose are cerebral damage and hypokalemia. Other complications include, pulmonary edema attributed to congestive heart failure and hypertensive crisis, as well as respiratory insufficiency. We report this case with a review of the literature.

생쥐 대장 평활근 세포에서 내향 정류성 칼륨 전류의 특성 연구

이은주,김명,정명섭,조향훈,김기훈,하현철,김준수,최석,전제열 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Objectives: K^(+) channels play an important role in regulating cellular excitability. The aim of this study was to know whether or not inward rectifier K^(+) channel exists in colonic smooth muscle cells. Methods: Mouse colonic smooth muscle cells were isolated using collagenase, and then we recorded their membrane currents using a whole-cell patch clamp technique. Results: With 90 mM K^(+) in bath, hyperpolarization-induced inward currents from -120 mV to 20 mV with 400 ms duration at a holding potential of -10 mV showed rapid activation, inactivation and inward rectification. The inactivation showed single exponential time course. Reduction of external K^(+) to 60 mM decreased the amplitudes of the currents in whole test voltage range and shifted the reversal potential to more negative potential. The inactivation process and peak currents of hyperpolarization-induced inward currents were not affected by removing external Na^(+). External Ba^(+) blocked hyperpolarization-induced inward currents by dose-dependent manner and pure Ba^(+)-sensitive currents showed strong inward rectification. Cs^(+) also suppressed hyper- polarization-induced inward currents. Ba^(+) and Cs^(+)-induced inhibitiOn of hyperpolarization-induced inward currents was voltage-dependent, and the extent of inhibition increasing with membrane hyperpolarization. Conclusions: These results suggest that inward rectifier KU channels may exist in proximal colonic smooth muscle and may play an important role in regulating membrane potential.

이형성 신장과 동반된 이소성 요관

김재헌,한민철,박성재,정준호,심봉석,조민선 이화여자대학교 의과대학 2005 EMJ (Ewha medical journal) Vol.28 No.1

Ectopic ureteral orifice presents predominantly in young girls with duplicated kidneys and ureters, and mostly drains from ectopic ureters were associated with non-duplicated upper urinary systems and it is called a single system ectopic ureter. It is frequently associated with renal dysplasia or agenesis and ureterocele. Compared with ectopic ureter draining from the duplicated kidney, the diagnosis of single system ectopic ureter is often delayed because the ectopic ureter may be associated with a single small dysplastic, poorly functioning kidney. We report a case of single system ectopic ureter associated with dysplastic and poorly functioning kidney.

LLCE법에 의한 천연산 은어의 휘발성 향기성분 분석

김훈,조우진,안준석,조두희,김지혜,차용준 창원대학교 생활과학연구소 2003 생활과학연구 Vol.- No.7

The volatile compounds in natural sweet smelt were analyzed by liquid liquid continuous extraction/gas chromatography/mass spectrometry (LLCE/GC/MS) methods. A total of 64 compounds were detected in sample, and these were mainly composed of lipid oxidative compounds such as aldehydes, ketones, alcohols, acids and hydrocarbons besides terpens and aromatic compounds. Among these, 9-carbon compounds including (E)-2-nonenal, (E,Z)-2,6-nonadienal and (E,Z)-3,6-nonadien-1-ol were suspected to have a key role on odor of natural sweet smelt because these compounds have low odor threshold and water melon-like and melon-like odor, characteristic odor in sweet smelt.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

Vertebroplasty Utilizing Percutaneous Vertebral Body Access (PVBA) Technique for Osteoporotic Vertebral Compression Fractures in the Middle Thoracic Vertebrae

Cho, Yong-Jun,Choi, Jong-Hun,Cho, Sung-Min The Korean Neurosurgical Society 2007 Journal of Korean neurosurgical society Vol.41 No.3

Objective : Percutaneous approach to the middle thoracic vertebra through the transpedicular route for the patients with osteoporotic vertebral compression fractures is difficult due to the small size of the pedicle and parasagittally oriented vertebra body anatomy. The percutaneous vertebral body access [PVBA] technique utilizing the posterolateral extrapedicular approach avoids the pedicle and provides direct access to the vertebral body. The objective of this study is to evaluate the efficacy of the vertebroplasty utilizing PVBA technique for osteoporotic vertebral compression fractures in the middle thoracic vertebrae. Methods : A retrospective review was done on 20 patients who underwent vertebroplasty utilizing PVBA technique performed for painful osteoporotic compression fracture in the middle thoracic vertebrae at 22 levels from May 2003 to June 2006. The average amount of the injected cement was 1.5-2.5ml. The postprocedural outcome was assessed using a visual analogue scale [VAS]. Results : The treated vertebrae were T5 [1 level], T6 [5 levels], 17 [7 levels], and T8 [9 levels]. The compression rate and kyphotic angle were improved after procedure from $18%{\pm}13.4$ to $16%{\pm}13.8$ [p > 0.05] and from $6.9^{\circ}{\pm}6.7$ to $6.6^{\circ}{\pm}6.2$ [p>005], respectively. Preprocedural VAS was $8.2{\pm}0.70$ and was decreased to $2.1{\pm}1.02$ [p < 0.01] after treatment. Postprocedural cement leakage was noted in 3 levels [13.7%]. There were no cases of leakage to epidural space or neural foramen, segmental artery injury, and pneumothorax. Conclusion : These results suggest that the complication rates are low and good results can be achieved with vertebroplasty utilizing PVBA technique for the osteoporotic vertebral compression fractures especially in the middle thoracic vertebrae.

A one-step colorimetric acid–base titration sensor using a complementary color changing coordination system

Cho, Hui Hun,Kim, Si Hyun,Heo, Jun Hyuk,Moon, Young Eel,Choi, Young Hun,Lim, Dong Cheol,Han, Kwon-Hoon,Lee, Jung Heon The Royal Society of Chemistry 2016 The Analyst Vol.141 No.12

<P>We report the development of a colorimetric sensor that allows for the quantitative measurement of the acid content via acid-base titration in a single-step. In order to create the sensor, we used a cobalt coordination system (Co-complex sensor) that changes from greenish blue colored Co(H2O)(4)(OH)(2) to pink colored Co(H2O)(6)(2+) after neutralization. Greenish blue and pink are two complementary colors with a strong contrast. As a certain amount of acid is introduced to the Co-complex sensor, a portion of greenish blue colored Co(H2O)(4)(OH)(2) changes to pink colored Co(H2O)(6)(2+), producing a different color. As the ratio of greenish blue and pink in the Co-complex sensor is determined by the amount of neutralization reaction occurring between Co(H2O)(4)(OH)(2) and an acid, the sensor produced a spectrum of green, yellow green, brown, orange, and pink colors depending on the acid content. In contrast, the color change appeared only beyond the end point for normal acid-base titration. When we mixed this Co-complex sensor with different concentrations of citric acid, tartaric acid, and malic acid, three representative organic acids in fruits, we observed distinct color changes for each sample. This color change could also be observed in real fruit juice. When we treated the Co-complex sensor with real tangerine juice, it generated diverse colors depending on the concentration of citric acid in each sample. These results provide a new angle on simple but quantitative measurements of analytes for on-site usage in various applications, such as in food, farms, and the drug industry.</P>

Wide-bandgap nanocrystalline silicon-carbon alloys for photovoltaic applications

Cho, Jun-Sik,Jang, Eunseok,Lim, Dongmin,Ahn, Seungkyu,Yoo, Jinsu,Cho, Ara,Park, Joo Hyung,Kim, Kihwan,Choi, Bo-Hun Elsevier 2018 Solar energy materials and solar cells Vol.182 No.-

<P><B>Abstract</B></P> <P>p-Type hydrogenated silicon carbide (p-SiC:H) films were prepared using plasma-enhanced chemical vapor deposition by systematically incorporating carbon into nanocrystalline silicon networks. The carbon content of the films was varied by adjusting the methane/silane (CH<SUB>4</SUB>/SiH<SUB>4</SUB>; R<SUB>C</SUB>) ratio. The chemical bonding, microstructural, and electro-optical properties of the films were investigated in detail. With increasing R<SUB>C</SUB>, the silicon-carbon bond density in the films increased gradually and the overall microstructure became amorphous. Through sophisticated control of the carbon content of the films during high hydrogen dilution deposition, p-type hydrogenated nanocrystalline SiC:H (p-nc-SiC:H) films with nanometer-scale Si crystallites embedded in an amorphous SiC:H matrix were obtained. The p-nc-SiC:H films had wide bandgaps larger than 2 eV and reduced parasitic light absorption at wavelengths below 550 nm. When using wide-bandgap p-nc-SiC:H films with superior electro-optical properties as window layers in n-i-p flexible and p-i-n semi-transparent nc-Si:H solar cells, in place of conventional p-nc-Si:H layers with narrow bandgaps, enhanced cell performance was achieved because of both high open circuit voltage (V<SUB>OC</SUB>) and high quantum efficiency values at short wavelengths of 350–550 nm. The conversion efficiencies of the flexible nc-Si:H solar cells increased from 6.37% (V<SUB>OC</SUB> = 0.41 V, J<SUB>SC</SUB> = 22.81 mA/cm<SUP>2</SUP>, and FF = 68.10%, where J<SUB>SC</SUB> is the short-circuit current density and FF is the fill factor, respectively) to 7.89% (V<SUB>OC</SUB> = 0.51 V, J<SUB>SC</SUB> = 24.04 mA/cm<SUP>2</SUP>, and FF = 64.37%). A further increase in the conversion efficiency to 9.18% was obtained by inserting a very thin, highly-doped p-nc-SiC:H buffer layer between a low-doped p-nc-SiC:H window layer and an indium tin oxide front contact. A significant increase in the conversion efficiency from 3.66% (V<SUB>OC</SUB> = 0.42 V, J<SUB>SC</SUB> = 14.83 mA/cm<SUP>2</SUP>, and FF = 58.69%) to 4.33% (V<SUB>OC</SUB> = 0.45 V, J<SUB>SC</SUB> = 17.74 mA/cm<SUP>2</SUP>, and FF = 54.18%) was achieved with the semi-transparent nc-Si:H solar cell, with an average optical transmittance of 17.29% in the visible wavelength region of 500–800 nm.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Wide-bandgap p-nc-SiC:H widow layers for photovoltaics solar cells were prepared. </LI> <LI> High-quality p-nc-SiC:H films were fabricated by PECVD. </LI> <LI> Enhanced performance was achieved in the Si-based solar cells. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Simple Decompression of the Ulnar Nerve for Cubital Tunnel Syndrome

Cho, Yong-Jun,Cho, Sung-Min,Sheen, Seung-Hoon,Choi, Jong-Hun,Huh, Dong-Hwa,Song, Joon-Ho The Korean Neurosurgical Society 2007 Journal of Korean neurosurgical society Vol.42 No.5

Objective : Cubital tunnel syndrome is the second most common entrapment neuropathy of the upper extremity. Although many different operative techniques have been introduced, none of them have been proven superior to others. Simple cubital tunnel decompression has numerous advantages, including simplicity and safety. We present our experience of treating cubital tunnel syndrome with simple decompression in 15 patients. Methods : According to Dellon's criteria, one patient was classified as grade 1, eight as grade 2, and six as grade 3. Preoperative electrodiagnostic studies were performed in all patients and 7 of them were rechecked postoperatively. Five patients of 15 underwent simple decompression using a small skin incision (2 cm or less). Results : Preoperative mean value of motor conduction velocity (MCV) within the segment (above the elbow-below the elbow) was $41.8{\pm}15.2\;m/s$ and this result showed a decrease compared to the result of MCV in the below the elbow-wrist segment ($57.8{\pm}6.9\;m/s$) with statistical significance (p<0.05). Postoperative mean values of MCV were improved in 6 of 7 patients from $39.8{\pm}12.1\;m/s$ to $47.8{\pm}12.1\;m/s$ (p<0.05). After an average follow-up of $4.8{\pm}5.3$ months, 14 patients of 15 (93%) reported good or excellent clinical outcomes according to a modified Bishop scoring system. Five patients who had been treated using a small skin incision achieved good or excellent outcomes. There were no complications, recurrences, or subluxation of the ulnar nerve. Conclusion : Simple decompression of the ulnar nerve is an effective and successful minimally invasive technique for patients with cubital tunnel syndrome.