酒酊依存 患者에서 末梢神經炎의 電氣生理學的 硏究

田珍淑,韓昊成 大韓神經精神醫學會 1996 신경정신의학 Vol.35 No.4

알코올성 신경염은 주정의존 환자의 약 34%에서 발생한다고 알려졌으며, 그 원인으로서는 알코올의 직접적인 독작용, 비타민 결핍, 영양결핍 등이 제시되고 있다. 저자들은 임상증상이 없이 검사상 나타나는 신경염의 이환이 어느 정도이며, 병인의 가능성이 높은 요인은 무엇인지 알아보고자 본 연구를 시행하였다. 주정의존으로 입원한 환자(N=47)에서 상지와 하지의 운동신경과 감각신경 및 근육에 대해 신경전도검사(이하 NCV) 및 근전도검사(이하 EMG)를 시행하고, 정상 대조군(N=17)에 대한 검사 결과와 비교하였으며, 여러 변인과의 상관성을 검토하였다. 1) 주정의존 환자 47명중 알코올성신경염의 임상증상을 지닌 환자는 8명(17.0%)이었으며, 신경전도검사 및 근전도검사상 34명(72.3%)에서 신경염의 소견을 보였다. 2) 주정의존 환자의 운동신경에 대한 NCV검사에서 대조군보다 환자군의 비골(peroneal) 신경의 진폭이 유의하게 감소되었고(p<0.01), 전도속도는 정중(median)신경(p<0.005) 과 척골 및 비골신경(각각 p<0.05)에서 유의하게 감소되었으며, 원위잠복기는 대조군과 유의한 차이가 없었다. 3) 주정의존 환자의 감각신경에 대한 NCV검사에서 진폭은 척골신경(p<0.0005)과 비복(sural) 신경(p<0.05)에서 유의하게 감소되었고, 전도속도는 정중신경(p<0.05)에서 유의하게 감소되었으며, 원위잠복기는 척골신경(p<0.005)에서 유의하게 지연되었다. 4) H-반사는 환자군에서 측정한 42명중 30명(71.4%)에서 이상소견(무반응)을 보였다. 5) 근전도검사상 47명중 15명(31.9%)에서 이상소견(휴식시 fibrillation potentials 및 / 또는 positive sharp waves, 작동시 motor unit action potential 수의 감소 및 하지근의 작동에 대한 polyphasic potential 증가)을 보였다. 6) 연령, 음주기간, 주정의존의 정도, 우울증의 심도, 인지기능장애, 간기능, 빈혈 및 혈중 folic acid치, 지질대사 등은 알코올성신경염과 유의한 상관관계가 없었다. 이상의 결과는 임상증상은 없으나 전기생리학적 검사상 발견되는 준임상적 알코올성신경염의 빈도가 예상 외로 높으며, 전기생리학적 검사소견은 축삭변성(axonal degeneration)의 가능성을 높이 시사하고 있어서 그 원인으로서 알코올의 직접적인 신경독작용을 고려해 볼 수 있다. The alcoholic neuropathies developed in approximately 34% of chronic alcoholics. Direct neurotoxic effect of alcohol, vitamin deficiencies and nutritional deficiencies were suggested to be the major causes of alcoholic neuropathies. The aims of this study were to identify the prevalence of subclinical peripheral neuropathies in alcohol dependence, and to speculate on the underlying mechanism of alcoholic neuropathies. The nerve conduction velocity(NCV) and electromyography(EMG) were tested for the male alcoholics(N=47) and normal controls(N=17), and the variables which might after the test result of NCV and EMG were discussed. 1) While 8(17.0%) out of 47 alcoholics clinically had neuropathies, the NCV and EMG detected signs of peripheral neuropathies in 34(72.3%) alcoholics. 2) On the motor NCV in alcoholics, the amplitude of peroneal nerve was significantly lowered(p<0.01). The conduction velocities were significantly reduced in the median(p<0.005), ulnar and peroneal(p<0.05 respectively) nerves. There was no significant differences in the distal latency comparing with control group. 3) On the sensory NCV in alcoholics, the amplitude was significantly lowered in ulnar(p<0.0005) and sural(p<0.05) nerves. The conduction velocities were significantly reduced in median nerve(p<0.05). The distal latencies were significantly delayed in ulnar nerve(p<0.005). 4) The H-reflex was absent in 30 alcoholics(71.4%) among 42 alcoholics. 5) On the EMG, such abnormal findings as the fibrillation potentials and/or positive sharp waves in rest, and the decreased numbers of motor unit action potentials and increased polyphasic potentials in volition of limb muscles were found in 15(31.9%) out of 47 alcoholics. 6) The alcoholic neuropathies were not correlated with variables like age, duration of alcohol drinking, severity of alcohol dependence, cognitive deficit, hepatic dysfunction, anemia and serum folic acid and lipid metabolism. In conclusion, the prevalence of subclinical neuropathies in alcoholics seemed to be much higher beyond expectation. The electrophysiological studies highly suggested that the cause of neuropathies was the direct neurotoxic effect of alcohol that might exert axonal degeneration.

지연유합과 불유합에서 저신호 강도 초음파의 유용성

윤여헌,김종오,고영도,유재두,정준모,오종건,방한천,최창호,신명철 대한골절학회 2003 대한골절학회지 Vol.16 No.1

목 적 : 저 신호 강도 초음파를 이용한 지연유합과 불유합의 치료에 대한 유용성을 알아보고자 하였다. 대상 및 방법 : 2001년 7월부터 2002년 5월까지 본원에 내원한 지연유합 7례와 불유합 8례를 대상으로 5개월간 저 신호 강도 초음파로 치료하여 5개월후 골유합 여부를 알아 보았다. 결 과 : 총 15례 중 대퇴골 간부 2례, 경골 간부 1례, 상완골 간부 1례, 요골 1례의 지연유합에서 골유합을 얻었고 대퇴골 간부 불유합 3례에서 유합을 얻었다. 지연주합은 71%의 유합율을, 불유합은 37.5%의 유합율을 보였다. 결 론 : 저 신호 강도 초음파는 골유합을 촉진 시킬 수 있으며 지연유합에서 시도해 볼 만 하나 불유합 치료를 위해서는 보다 많은 연구가 필요 하다. Purpose : To evaluation of usefulness of low-intensity ultrasound for nonunion and delayed union. Materials and Methods : For 5 months, we treated 7 delayed union and 8 nonunion using low-intensity ultrasound. After 5 months, in checked X-ray AP and Lateral view, when cortical bridge formation was done, we through union. Results : In 7 delayed union, 5 cases-2 femur, tibia, humerus, radius were healed. In 8 nonunion, 3 femur nonunion were healed. Union rate was 71% in delayed union 37.5% in nonunion. Conclusion : we thought that the low-intensity ultrasound has capacity of induction of union and was considered as the method of treatment for delayed union.

Effect of the Circle-Grid Electrodes on Concentrated GaAs Solar Cell Efficiency

Chen-Chen Chung,Binh Tinh Tran,Ming-Hung Han,Kung-Liang Lin,Hung-Wei Yu,Yen-Teng Ho,Chun-Yen Chang,Edward Yi Chang 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.5

In this study, we investigate the effect of the shading factor of the front grid pattern on concentrated solar cell efficiency, taking the trade-off between the series resistance of the electrodes and the amount of incident light into consideration. We examine the thermal effect with regard to five different circle-grid electrode patterns of the front contact. The front contacts with different grid patterns affect the characteristics of light-concentratedtype GaAs single-junction solar cells. The device parameters analyzed include the open-circuit voltage (Voc), short-circuit current (Isc), fill factor (FF) and conversion efficiency (η). The results of our study show that for a concentration ratio greater than 60x with AM1.5G, the device with a shading factor of 7.1% has the best cell efficiency of 27.05%, due to the smaller current crowding at the center spot. The results indicate that the conversion efficiency of solar cells can be improved by establishing a compromise between the shading effect and the series resistance effect.

The Effect of CdS QDs Structure on the InGaP/GaAs/Ge Triple Junction Solar Cell Efficiency

Chen-Chen Chung,Binh Tinh Tran,Hau-Vei Han,Yen-Teng Ho,Hung-Wei Yu,Kung-Liang Lin,Hong-Quan Nguyen,Peichen Yu,Hao-Chung Kuo,Edward Yi Chang 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.2

This work describes optical and electrical characteristics of InGaP/GaAs/Ge triple-junction (T-J) solar cells with CdS quantum dots (QDs) fabricated by a novel chemical solution. With the anti-reflective feature at long wavelength and down-conversion at UV regime, the CdS quantum dot effectively enhance the overall power conversion efficiency more than that of a traditional GaAs-based device. Experimental results indicate that CdS quantum dot can enhance the short-circuit current by 0.33 mA/cm2, which is observed for the triple-junction solar cells with CdS QDs of about 3.5 nm in diameter. Moreover, the solar cell conversion efficiency is improved from 28.3% to 29.0% under one-sun AM 1.5 global illumination I-V measurement.

Experimental Evidence for Drude-Boltzmann-Like Transport in a Two-Dimensional Electron Gas in an AlGaN/GaN Heterostructure

Jing-Han Chen,C.-T. Liang,D.H. Youn,Eun-Jin Lee,Gil-Ho Kim,Hun Park,Hyun-Ick Cho,Jung-Hee Lee,Jung-Kai Tsai,Jyun-Ying Lin,Y. F. Chen 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.6

AlGaN/GaN heterostructures have been attracting a great deal of interest because of their great potential applications as light-emitting-diodes, high-electron-mobility transistors (HEMTs), and detectors operating in the visible-to-ultraviolet range. The performances of these devices are governed by the electronic properties of the two-dimensional electron gas (2DEG) formed at the interface of AlGaN/GaN heterostructure. In this work, we report transport measurements for an AlGaN/GaN 2DEG as functions of the magnetic field B over a wide range of temperature (4.682 K T 80 K). At the highest measurement temperature of 80 K, the longitudinal resistance is nominally Bindependent, compelling experimental evidence for Drude-Boltzmann-like transport in a 2D system.

Dynamics of dissolved organic matter in riverine sediments affected by weir impoundments: Production, benthic flux, and environmental implications

Chen, Meilian,Kim, Sung-Han,Jung, Heon-Jae,Hyun, Jung-Ho,Choi, Jung Hyun,Lee, Hyo-Jin,Huh, In-Ae,Hur, Jin Elsevier 2017 Water research Vol.121 No.-

<P><B>Abstract</B></P> <P>In order to understand the characteristics and dynamics of dissolved organic matter (DOM) in the sediment of rivers affected by impoundments, we examined the vertical profiles and the benthic fluxes of DOM in four different core sediments located at upstream sites of weirs in major rivers of South Korea. In three out of four sites, exponential accumulation of dissolved organic carbon (DOC) with depth was observed with the signature of seasonal variability. Except for the site displaying a below-detection limit of Fe(II), the general accumulation trends of DOC with depth was concurrent with the increases of Fe(II) and NH<SUB>4</SUB> <SUP>+</SUP> and the decrease of PO<SUB>4</SUB> <SUP>3-</SUP>, signifying a close linkage of the DOM dynamics with anaerobic respiration via iron reduction, an important early diagenesis pathway. The estimated benthic fluxes from the cores revealed that the sediments likely serve as DOC, chromophoric DOM (CDOM), and fluorescent DOM (FDOM) sources to the overlying water. The benthic effluxes based on DOC were comparable to the ranges previously reported in lake and coastal areas, and those of CDOM and FDOM showed even higher levels. These findings imply that impoundment-affected river systems would change the DOM composition of the overlying water, ultimately influencing the subsequent water treatment processes such as disinfection byproducts production and membrane fouling. A simple mass balance model indicated that the impoundment-affected river sediments may operate as a net carbon sink in the environments due to a greater extent of sedimentation compared to the estimated benthic efflux and sediment biological respiration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> DOC is exponentially accumulated with depth in most impoundment-affected sites. </LI> <LI> Positive correlation of DOC with Fe(II) reveals DOM production via iron reduction. </LI> <LI> Sediments serve as sources of DOC, CDOM, and FDOM to overlying water. </LI> </UL> </P>

Structural insights into the dual substrate specificities of mammalian and <i>Dictyostelium</i> dihydropteridine reductases toward two stereoisomers of quinonoid dihydrobiopterin

Chen, Cong,Kim, Hye Lim,Zhuang, Ningning,Seo, Kyung Hye,Park, Ki Hun,Han, Chang-deok,Park, Young Shik,Lee, Kon Ho Elsevier 2011 FEBS letters Vol.585 No.17

<P><B>Highlights</B></P><P>► The binary structure of <I>Dic</I>DHPR-NAD<SUP>+</SUP> has been solved in 2.16Å resolution. ► Structural changes in NADH binding site result in a higher <I>K</I><SUB>m</SUB> for NADH than mammals. ► A mammalian DHPR carries a dual substrate activity verified by in vitro assay. ► We built structural models of the ratDHPR and <I>Dic</I>DHPR in complex with two substrates.</P> <P><B>Abstract</B></P><P>Up to now, <SMALL>D</SMALL>-<I>threo</I>-tetrahydrobiopterin (DH<SUB>4</SUB>, dictyopterin) was detected only in <I>Dictyostelium discoideum</I>, while the isomer <SMALL>L</SMALL>-<I>erythro</I>-tetrahydrobioterin (BH<SUB>4</SUB>) is common in mammals. To elucidate the mechanism of DH<SUB>4</SUB> regeneration by <I>D. discoideum</I> dihydropteridine reductase (<I>Dic</I>DHPR), we have determined the crystal structure of <I>Dic</I>DHPR complexed with NAD<SUP>+</SUP> at 2.16Å resolution. Significant structural differences from mammalian DHPRs are found around the coenzyme binding site, resulting in a higher <I>K</I><SUB>m</SUB> value for NADH (<I>K</I><SUB>m</SUB>=46.51±0.4μM) than mammals. In addition, we have found that rat DHPR as well as <I>Dic</I>DHPR could bind to both substrates quinonoid-BH<SUB>2</SUB> and quinonoid-DH<SUB>2</SUB> by docking calculations and have confirmed their catalytic activity by in vitro assay.</P><P><B>Structured summary of protein interactions</B></P><P><B>DHPR</B>bindsto<B>DHPR</B> by X-ray crystallography(View interaction)</P>

Different Clinical Characteristics Among Aeromonas hydrophila, Aeromonas veronii biovar sobria and Aeromonas caviae Monomicrobial Bacteremia

Han-Chuan Chuang,Yu-Huai Ho,Chorng-Jang Lay,Lih-Shinn Wang,Yeong-Shu Tsai,Chen-Chi Tsai 대한의학회 2011 Journal of Korean medical science Vol.26 No.11

This study aimed to compare the clinical presentations of Aeromonas hydrophila, A. veronii biovar sobria and A. caviae monomicrobial bacteremia by a retrospective method at three hospitals in Taiwan during an 8-yr period. There were 87 patients with A. hydrophila bacteremia, 45 with A. veronii biovar sobria bacteremia and 22 with A. caviae bacteremia. Compared with A. hydrophila and A. veronii biovar sobria bacteremia, A. caviae bacteremia was more healthcare-associated (45 vs 30 and 16%; P = 0.031). The patients with A. caviae bacteremias were less likely to have liver cirrhosis (27 vs 62 and 64%;P = 0.007) and severe complications such as shock (9 vs 40 and 47%; P = 0.009) and thrombocytopenia (45 vs 67 and 87%; P = 0.002). The APACHE II score was the most important risk factor of Aeromonas bacteremia-associated mortalities. The APACHE II scores of A. caviae bacteremias were lower than A. hydrophila bacteremia and A. veronii biovar sobria bacteremia (7 vs 14 and 16 points; P = 0.002). In conclusion, the clinical presentation of A. caviae bacteremia was much different from A. hydrophila and A. veronii biovar sobria bacteremia. The severity and mortality of A. caviae bacteremia were lower than A. hydrophila or A. veronii biovar sobria bacteremia.

Modulation of elastin exon 26A mRNA and protein expression in human skin <i>in vivo</i>

Chen, Zhou,Shin, Mi Hee,Moon, Young Ji,Lee, Se Rah,Kim, Yeon Kyung,Seo, Jo-Eun,Kim, Ji Eun,Kim, Kyu Han,Chung, Jin Ho Blackwell Publishing Ltd 2009 Experimental dermatology Vol.18 No.4

<P>Abstract: </P><P>Photoaged skin contains elastotic materials in the upper reticular dermis, a result of a commonly known as solar elastosis. It is known that the primary transcript of elastin undergoes extensive alternative splicing and that this results in the translation of multiple heterogeneous protein isoforms. In this study, we found that UV irradiation and heat treatment increased the levels of elastin transcript containing exon 26A and its encoded elastin isoform in the epidermis of human skin <I>in vivo</I> and in cultured human keratinocytes <I>in vitro</I>. We also found that the elastin transcript containing exon 26A was upregulated in photoaged forearm skin compared with intrinsically aged buttock skin in the same elderly individuals. We observed that topical retinoic acid treatment to human skin did not increase the expression of exon 26A mRNA, but that tropoelastin mRNA expression was increased by this treatment. These findings suggest that the production of the elastin isoform containing exon 26A peptide is increased by UV exposure and heat treatment in human skin <I>in vivo</I> and that it may play an important role in the development of solar elastosis in photoaged human skin.</P>

Harmonic Generation and System Response Characteristic in Electrified Railway - Focused on Measurement and Analysis -

Han-Min Lee,Gil-Dong Kim,Kwang-Hae Oh,An-Ho Lee,Chen-Soo Ha 전력전자학회 2004 ICPE(ISPE)논문집 Vol.- No.-

Harmonic current originating from electric locomotives can be magnified due to the impedance characteristics of power supply circuit and bring about various problems. That is, electromagnetic interference with communication lines, operational trouble in signaling, overheat and/or vibration in po wer capacitor, malfunction in protection relay and so on. Therefore, the exact assessment of the harmonic current flow must be undertaken at designing and planning stage for the electric traction systems.<br/> For these reasons, we proposed a new approach to model and to analyze traction power feeding system focused on system response to current and voltage harmonic. Moreover, harmonic characteristics in electric train depend on its operational modes. Therefore, Measurements of harmonics are performed on the real railway power supply systems under normal operation. The spectrum and distortion analyses in measurement data are variously described in this study.