주산기 뇌손상의 신경병리적 기전

송주영,김진상,Song Ju-Young,Kim Jin-Sang 대한물리치료학회 2003 대한물리치료학회지 Vol.15 No.4

신생아의 정상적인 발달을 저해하고 조기 사망의 주된 원인이 되고 있는 주산기 뇌손상에 관한 신경병리적 기전을 살펴보고자 하였다. 발달하고 있는 과정에서의 주산기 뇌손상은 주로 저산소성-허혈성 뇌손상과 출혈성 뇌손상에 의한 경우가 많다. 저산소성-허혈성 뇌손상과 관련하여 에너지 부전, 세포흥분독성, 미성숙 백질의 선택적 취약성을 고려해 볼 수 있다. 첫번째, 세포호흡에 관여하는 미토콘드리아의 손상과 관련하여 즉각적인 병리와 함께 지연된 양상의 손상을 보인다. 미토콘드리아의 호흡률이 감소하고 칼슘이온의 농도가 상승하여 세포 괴사 및 세포사멸 과정이 진행된다. 두번째, 흥분성 아미노산과 관련하여 미성숙한 뇌에는 NMDA 수용기-채널 복합체의 기능이 매우 풍부하고, phosphoinositide 가수분해가 높아서 흥분독성에 상당히 취약하다. 세 번째, 수초 형성에 중요한 역할을 하는 희돌기교세포가 주산기 뇌손상 특히, 저산소성-허혈성 손상에 취약하다. 희돌기교세포는 글루타메이트에 의한 자유유리기과 사이토카인 손상에 취약하다. 뇌출혈과 관련하여, 미성숙한 뇌는 뇌실 주위에 혈관층이 풍부하나 매우 약한 상태로 재관류 혹은 혈류의 증가로 인해 쉽게 파열된다. 특히 32주 이내인 경우 이러한 손상으로 인해 뇌실주위 백질연화증이 초래된다.

175mm 포탄추진제로부터 nitrocellulose의 고순도 분리에 관한 연구

송주영,Song, Ju-Yeong 한국응용과학기술학회 2015 한국응용과학기술학회지 Vol.32 No.2

The purpose of this study is to separate nitrocellulose from 175 mm ammunition propellant by environmentally responsible recovery method. Recovery of nitrocellulose from obsolete ammunition is much more desirable than destruction since it can be reused in the several purpose. In spite of durable demilitarization of obsolete ammunition, the current holding amount of obsolete ammunition is gradually increasing and accumulated. The existing demilitarization methods, such as incineration and priming are strictly restricted for the noise, dust, oscillation and air and soil pollution. This study is focused on the separation of nitrocellulose by environmentally responsible recovery method by the solubility difference of nitrocellulose in nonpolar solvent. The purity of an extracted nitrocellulose was analysed by IR and TLC method and was clarified as very high.

폐암 환자의 방사선수술 시 호흡연동 방사선치료 방법의 적용을 통한 계획용표적체적 감소 효과 분석

송주영,나병식,정웅기,안성자,남택근,윤미선,정재욱,Song, Ju-Young,Nah, Byung-Sik,Chung, Woong-Ki,Ahn, Sung-Ja,Nam, Taek-Keun,Yoon, Mee-Sun,Jung, Jae-Uk 한국의학물리학회 2008 의학물리 Vol.19 No.4

The application of a respiratory gated radiotherpy method to the lung radiation surgery was evaluated compared with the conventional method in which the whole tumor motion range is considered in the delineation of PTV (Planning target volume). The four dimensional CT simulation images were acquired for the five NSCLC (Non-small cell lung cancer) patients for radiation surgery. The respiratory gated plan was prepared with the 50% phase CT images and the conventional method was planned based on the ITV (Internal target volume) which include all the target volumes created in each phase CT images within a whole respiratory period. The DVH (Dose volume histogram) of OAR (Organ at risk) which calculated in each method was compared for the evaluation of the plan properness. The relative decrease of OARs' DVH were verified in the application of respiratory gated method. The average decrease rate were $16.88{\pm}9.97%$ in the bronchus, $34.13{\pm}19.15%$ in the spinal cord, $28.42{\pm}18.49%$ in the chest wall and $32.48{\pm}16.66%$ in the lung. Based on these results, we can verified the applicability and the effectiveness of the respiratory gated method in the lung radiation surgery.

토모테라피를 이용한 폐종양 방사선수술 계획 시 선량 분석

송주영,정재욱,윤미선,안성자,정웅기,나병식,남택근,Song, Ju-Young,Jung, Jae-Uk,Yoon, Mee-Sun,Ahn, Sung-Ja,Chung, Woong-Ki,Nah, Byung-Sik,Nam, Taek-Keun 한국의학물리학회 2011 의학물리 Vol.22 No.4

The applicability and feasibility of TomoTherapy in the lung radiation surgery was analyzed by comparison of the calculated dose distribution in TomoTherapy planning with the results of conventional IMRS (intensity modulated radiation surgery) using LINAC (linear accelerator). The acquired CT (computed tomograph) images of total 10 patients whose tumors' motion were less than 5 mm were used in the radiation surgery planning and the same prescribed dose and the same dose constraints were used between TomoTherapy and LINAC. The results of TomoTherapy planning fulfilled the dose requirement in GTV (gross tumor volume) and OAR (organ at risk) in the same with the conventional IMRS using LINAC. TomoTherapy was superior in the view point of low dose in the normal lung tissue and conventional LINAC was superior in the dose homogeneity in GTV. The calculated time for treatment beam delivery was long more than two times in TomoTherapy compared with the conventional LINAC. Based on the results in this study, TomoTherapy can be evaluated as an effective way of lung radiation surgery for the patients whose tumor motion is little when the optimal planning is produced considering patient's condition and suitability of dose distribution.

탄성 및 비탄성 좌굴 고유치해석을 이용한 강뼈대구조의 유효좌굴길이

송주영,경용수,김문영,Song, Ju-Young,Kyung, Yong-Soo,Kim, Moon-Young 한국전산구조공학회 2005 한국전산구조공학회논문집 Vol.18 No.2

An improved method for evaluating effective buckling lengths of beam-column members in plane frames is newly proposed based on system inelastic buckling analysis. To this end, the tangent stiffness matrix of be am-column elements is first calculated using stability functions and then the inelastic buckling analysis method is presented. The scheme for determining effective length of individual members is also addressed. Design examples and numerical results ?uc presented to show the validity of the proposed method.

척수 운동신경원의 기능과 관련된 생존운동신경원 단백질의 역할

송주영,권영실,남기원,송주민,김동현,김석범,문동철,최진호,김진상,Song, Ju-Young,Kown, Young-Shil,Nam, Ki-Won,Song, Ju-Min,Kim, Dong-Hyun,Kim, Suk-Bum,Moon, Dong-Chul,Choi, Ji-Ho,Kim, Jin-Sang 대한물리치료학회 2001 대한물리치료학회지 Vol.13 No.2

This review highlights the ontogenesis and the differentiation of motor neuron in spinal cord, and introduce the survival motor neuron(SMN) which is associated with growth and survival of motor neurons. The differentiation of floor plate cells and motor neurons in the vertebrate neural tube appears to be induced by signals from the notochord. This signal is Sonic hedgehog(Shh). The early development of motor neurons involves the inductive action of Shh. The SMN gene is essential for embryonic viability. SMN mRNA is also expressed in virtually all cell types in spinal cord, including large motor neurons. The SMN protein is involved in RNA processing and during early embryonic development is necessary fer cell survival. Two SMN genes are present in 5q 13 in humans: the telomeric gene(SMNt), which is the SMA-determining gene, and the centromeric analog gene(SMNc). The majority of transcripts from the SMNt gene are full length but, major transcripts of the SMNc gene have a high degrees of alternative splicing and tend to have little or no exon 7. The SMN is involved in the RNA processing(the biogenesis of snRNPs and pre-mRNA splicing), the anti-apoptotic effects, and regulating gene expression.

탄성좌굴 고유치 및 2차 탄성해석법을 이용한 평면강절프레임의 개선된 좌굴설계법

송주영,경용수,김남일,김문영,Song, Ju-Young,Kyung, Yong-Soo,Kim, Nam-Il,Kim, Moon-Young 한국전산구조공학회 2005 한국전산구조공학회논문집 Vol.18 No.2

An improved stability design method for beam-columns of plane frames is proposed based on system buckling analysis and second-order elastic analysis. For this, the tangent stiffness matrix of beam-column elements is first derived using stability functions and a procedure for evaluating effective buckling lengths is reviewed using elastic system buckling analysis. And then the second-order analysis procedure is presented considering $P-\Delta$ effects and is compared with the closed-form solution through numerical examples. Design examples showing the validity of the proposed method we presented and their numerical results are compared with those obtained from the conventional stability design methods. Finally some useful conclusions are drawn.

Evaluation of Dose Distributions Recalculated with Per-field Measurement Data under the Condition of Respiratory Motion during IMRT for Liver Cancer

송주영,김용협,정재욱,윤미선,안성자,정웅기,남택근,Song, Ju-Young,Kim, Yong-Hyeob,Jeong, Jae-Uk,Yoon, Mee Sun,Ahn, Sung-Ja,Chung, Woong-Ki,Nam, Taek-Keun Korean Society of Medical Physics 2014 의학물리 Vol.25 No.2

The dose distributions within the real volumes of tumor targets and critical organs during internal target volume-based intensity-modulated radiation therapy (ITV-IMRT) for liver cancer were recalculated by applying the effects of actual respiratory organ motion, and the dosimetric features were analyzed through comparison with gating IMRT (Gate-IMRT) plan results. The ITV was created using MIM software, and a moving phantom was used to simulate respiratory motion. The doses were recalculated with a 3 dose-volume histogram (3DVH) program based on the per-field data measured with a MapCHECK2 2-dimensional diode detector array. Although a sufficient prescription dose covered the PTV during ITV-IMRT delivery, the dose homogeneity in the PTV was inferior to that with the Gate-IMRT plan. We confirmed that there were higher doses to the organs-at-risk (OARs) with ITV-IMRT, as expected when using an enlarged field, but the increased dose to the spinal cord was not significant and the increased doses to the liver and kidney could be considered as minor when the reinforced constraints were applied during IMRT plan optimization. Because the Gate-IMRT method also has disadvantages such as unsuspected dosimetric variations when applying the gating system and an increased treatment time, it is better to perform a prior analysis of the patient's respiratory condition and the importance and fulfillment of the IMRT plan dose constraints in order to select an optimal IMRT method with which to correct the respiratory organ motional effect.

Cone-beam CT 영상 획득 시 호흡에 의한 영향 분석

송주영,나병식,정웅기,안성자,남택근,윤미선,Song, Ju-Young,Nah, Byung-Sik,Chung, Woong-Ki,Ahn, Sung-Ja,Nam, Taek-Keun,Yoon, Mi-Sun 한국의학물리학회 2007 의학물리 Vol.18 No.2

The cone-beam CT (CBCT) which is acquired using on-board imager (OBI) attached to a linear accelerator is widely used for the image guided radiation therapy. In this study, the effect of respiratory motion on the quality of CBCT image was evaluated. A phantom system was constructed in order to simulate respiratory motion. One part of the system is composed of a moving plate and a motor driving component which can control the motional cycle and motional range. The other part is solid water phantom containing a small cubic phantom ($2{\times}2{\times}2cm^3$) surrounded by air which simulate a small tumor volume in the lung air cavity CBCT images of the phantom were acquired in 20 different cases and compared with the image in the static status. The 20 different cases are constituted with 4 different motional ranges (0.7 cm, 1.6 cm, 2.4 cm, 3.1 cm) and 5 different motional cycles (2, 3, 4, 5, 6 sec). The difference of CT number in the coronal image was evaluated as a deformation degree of image quality. The relative average pixel intensity values as a compared CT number of static CBCT image were 71.07% at 0.7 cm motional range, 48.88% at 1.6 cm motional range, 30.60% at 2.4 cm motional range, 17.38% at 3.1 cm motional range The tumor phantom sizes which were defined as the length with different CT number compared with air were increased as the increase of motional range (2.1 cm: no motion, 2.66 cm: 0.7 cm motion, 3.06 cm: 1.6 cm motion, 3.62 cm: 2.4 cm motion, 4.04 cm: 3.1 cm motion). This study shows that respiratory motion in the region of inhomogeneous structures can degrade the image quality of CBCT and it must be considered in the process of setup error correction using CBCT images.

토모테라피에서 계획용표적체적 설정 시 필드 폭 영향 분석

송주영,나병식,정웅기,안성자,남택근,윤미선,정재욱,Song, Ju-Young,Nah, Byung-Sik,Chung, Woong-Ki,Ahn, Sung-Ja,Nam, Taek-Keun,Yoon, Mee-Sun,Jung, Jae-Uk 한국의학물리학회 2010 의학물리 Vol.21 No.4

The Hi-Art system for TomoTherapy allows only three (1.0 cm, 2.5 cm, 5.0 cm) field widths and this can produce different dose distribution around the end of PTV (Planning target volume) in the direction of jaw movement. In this study, we investigated the effect of field width on the dose difference around the PTV using DQA (Delivery quality assurance) phantom and real clinical patient cases. In the analysis with DQA phantom, the calculated dose and irradiated films showed that the more dose was widely spreaded out in the end region of PTV as increase of field width. The 2.5 cm field width showed a 1.6 cm wider dose profile and the 5.0 cm field width showed a 4.2 cm wider dose profile compared with the 1.0 cm field width in the region of 50% of maximum dose. The analysis with four patient cases also showed the similar results with the DQA phantom which means that more dose was irradiated around the superior and inferior end of PTV as an increase of field width. The 5.0 cm field width produced the remarkable high dose distribution around the end region of PTV and we could evaluate the effect quantitatively with the calculation of DVH (Dose volume histogram) of the virtual PTVs which were delineated around the end of PTV in the direction of jaw variation. From these results, we could verify that the margin for PTV in the direction of table movement should be reduced compared with the conventional margin for PTV when the large field such as 5.0 cm was used in TomoTherapy.