• 대한의용생체공학회:의공학회지
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• 제25권5호
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• pp.323-328
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• 2004

대뇌조직 구분을 위한 실험적인 정보를 제공하기 위한 뇌조직 확률 지도를 개발하는 경우 개인마다 구조적으로 다양한 형태를 가진 뇌의 특성과 특히 인종간의 두드러진 차이론 반드시 고려해야 한다 본 연구에서는 특정 그룹에 대한 뇌조직 확률 지도를 제작하는데 필요한 절차를 알아보고 나이에 따른 그룹간의 뇌조직 확률 지도의 구조적인 차이를 살펴보고자 한다 피험자 그룹은 100명의 건강한 한국인이며 나이에 따라 두 그룹으로 분류하였다. 뇌 확률 지도의 기준 좌표계를 설정하기 위해 전체 그룹 내의 모든 피험자의 뇌 영상에 대한 평균 영상을 구하고, 각 뇌 영상을 기준 좌표계로 정규화 시킨다. 정규화 과정에서 얻어진 변환 매개 변수를 미리 각 뇌조직(회질, 백질, 뇌척수액)으로 분할된 피험자의 영상에 적용하고 각 그룹 내에서 변환된 뇌 조직 영상을 평균함으로써 뇌 조직 확률 지도를 완성하였다. 나이에 따른 구조적인 차이를 살펴보기 위해 그룹간 확률 값의 차이 영상을 구하였다. 이전 연구결과에서와 마찬가지로 나이가 증가함에 따라 뇌실이 확대되고 회질의 위축이 전체적인 뇌 영역에서 일어났다. 그러므로 우리는 대뇌 조직 분할을 위해 설험적인 정보들을 사용하고자 할 때는 특정 그룹에 대한 뇌 확률 지도를 사용할 것을 제안한다.

• 대한핵의학회지
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• 제29권3호
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• pp.328-331
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• 1995

$^{99m}Tc$ labeled PnAO(propylene amine oxime) derivatives have been widely studied as brain perfusion agents. We synthesized and characterized a PnAO derivative, (RR/SS/ meso)-4,8-diaza-3,9-dimethylundecane-2, 10-dione bisoxime(PRODD). Proton-NMR spectroscopy and thin layer chromatography(silica gel) were performed for its characterization. PRODD was labeled with $^{99m}Tc$ using stannous chloride as reducing agent. The labeling efficiency was determined to be about 85%. Brain uptakes of $4.16{\pm}0.42$ %ID/g and $3.24{\pm}0.13$ %ID/g were found after 10min and 30min after intravenous injection. Brain-to-blood ratios were 1.17 and 0.75 at 10 and 30 minutes, which were lower than 1.3 and 1.9 of the ratios with commercial ${\pm}$-HMPAO. Autoradiographs of rat brain sections showed the gray matter to white matter ratios of $1.13{\pm}0.10$ at 30 min after intravenous injection, which was lower than $1.94{\pm}0.19$ of commercial $^{99m}Tc$-HMPAO. With the above findings, we concluded that the lipophilic $^{99m}Tc$-PRODD complex was able to cross the blood-brain barrier, however the complex showed lower uptake than $^{99m}Tc$-HMPAO in mouse or rat brains. We could suggest possibility that PRODD could be used as another $^{99m}Tc$ chelator.

• 핵의학기술
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• 제26권1호
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• pp.33-37
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• 2022

¹⁸F-FBB 판독은 회백질과 백질의 신호강도를 육안으로 비교하여 이루어진다. 정량화된 영상분석을 판독과 비교하여 영상분석의 유용성을 평가하고자 한다. 환자는 판독결과를 기준으로 음성과 양성을 100명씩 나누었고 FBB 300 MBq 주입하고 90분 뒤 20분간 촬영했다. 장비는 Discovery 600 (GE Healthcare, MI, USA)을 사용하였다. 제조사에서 제공하는 아밀로이드 판독 기준을 근거하여 4개의 관심영역을 설정하였다. 영상분석은 각 SUVmean을 소뇌로 나누어 SUVr를 산출하고 전체 영역에서의 평균 SUVr로 진행하였다. 통계분석은 ROC Curve를 통한 Cutoff 도출과 독립표본 t-test의 그룹간 차이, 그리고 Kappa test를 통한 판독결과와 일치도를 분석하였다. 전체 영역에서의 평균 SUVr의 Cutoff는 1.23으로 나왔다. Cutoff를 사용한 판독결과와 일치도는 음성에서 95/100 (95 %), 양성에서 92/100 (92 %)로 나왔다. t-test 결과 그룹 간에 통계적으로 유의한 차이가 있었고(P < 0.05) Kappa 통계 결과 0.867로 높은 일치도를 나타냈다(P < 0.05). 영상분석의 결과가 통계적으로 유의하며 판독결과에도 높은 일치도를 보여 주었다. 추가적으로 FBB 영상분석은 아밀로이드가 축적된 부위를 3D 매핑하여 볼 수 있고 위치추정이 가능하며 정량분석 결과를 세분화하여 볼 수 있다. 정량화된 FBB 영상분석을 보조지표로 활용한다면 판독에 도움이 될 것으로 사료된다.

• 대한영상의학회지
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• 제84권1호
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• pp.240-252
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• 2023

목적 소아 환자에서 두부 컴퓨터단층촬영(이하 CT)에 대한 딥러닝 이미지 재구성(deep learning image reconstruction; 이하 DLIR; TrueFidelity; GE Healthcare, Milwaukee, WI, USA)의 효과를 평가하고자 한다. 대상과 방법 총 126개의 소아 두부 CT 이미지를 수집했으며, adaptive statistical iterative reconstruction (이하 ASiR)-V를 사용한 반복적 재구성 및 세 가지 수준의 DLIR을 사용한 재구성을 시행하였다. 각 이미지 세트 그룹은 환자의 연령에 따라 4개의 그룹으로 구분하였으며 각 연령군의 임상 및 방사선량 관련 데이터를 검토하였다. 양적 매개 변수에는 signal to noise ratio (이하 SNR) 및 contrast to noise ratio (이하 CNR)가 포함되었으며 질적 매개 변수로 영상의 잡음(noise), 회백질의 구분 정도, 선명도, 인공물 및 수용 가능성(acceptability), 영상의 질감이 포함되었고 이에 대한 평가와 비교를 시행하였다. 결과 모든 연령 그룹의 모든 수준의 SNR 및 CNR은 높은 수준의 DLIR 사용 시 증가하였다. ASiR-V와 비교했을 때 높은 수준의 DLIR은 SNR 및 CNR이 개선되었다(p < 0.05). 그리고 DLIR의 수준이 증가될수록 순차적인 잡음 감소, 회백질 구분 개선, 선명도 개선이 나타났다. 이러한 변수들에서 높은 수준의 DLIR 사용 시 ASiR-V와 유사한 정도의 수치가 측정되었다. 인공물과 수용 가능성의 경우에 적용된 DLIR 수준 간에 큰 차이를 보이지 않았다. 결론 소아 두부 CT에 고수준 DLIR을 적용하면 영상의 노이즈를 줄일 수 있으나 인공물 처리에 대한 개선이 필요하다.

• 한국조경학회지
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• 제19권2호
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• pp.65-74
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• 1991

The purpose of this study was to find the basic application of Disporum genus in landscape-arc-hitectual space. Environment of native site (Daeducksan, Piseulsan) and growth characteristics of experiment plot were investigated and analyzed in this study. The results of this study were as follows; 1. In the case of environment of native site, the relative light intensity was about 10% and distribution of species were primarily north slope. Gradient of Daeducksan and Piseulsan were 10$^{\circ}$, 18$^{\circ}$ Soil textures was Lic both and field capacity of Daeducksan and Piseulsan were 69%, 73.5%. The soil pH of Daeducksan and Piseulsan were 6.1 and 5.8. The both content of organic matter and C.E.C. were high markedly. The P2O5 content of Daeducksan showed high but total nitrogen showed nearly the same level when comparing with the common dry field condition. 2. In tree layer, Daeducksan composed of broadleaved forest of 80% involving Quercus variabilis, and Piseulsan composed of coniferous forest of 80% involving Pinus densiflora on the other hand. Daeducksan, therefore, was more appearance species than Piseulsan in herbaceous layer. 3. Result in ANOVA Test, significance followed with light intensity was recognized in plant height, leaf width, leaf length, leaf thick and No. of leaf, while in the case of soil was not. Plant height was longest in 1% and leaf width, leaf length was largest in 25%. Therefore ornamental value of leaf was the very best in 25%. 4. Result in correlation coefficient analysis, plant height was correlated leaf width, leaf length. The longer plant height, the smaller leaf width, leaf length. In relative light intensity of 1%, flower was hardly expected because of the more shade, the less flower. Disporum smilacinum is expected great use as ground covers in the shades of tall-building or hdavy woods.

• The Korean Journal of Pain
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• 제9권2호
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• pp.326-335
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• 1996

Background: Though a number of studies have described the distribution of substance P(SP)-like immunoreactivity in the spinal cord, they have been focused on lamina I and II of the dorsal horn and there are little morphological studies on the topographic distribution and ultrastructure of the SP immunoreactive neurons especially in the ventral horn of the spinal cord. this study was conducted to identify distribution pattern of SP immunoreactive neurons and to difine the synaptic organization of their processes in ventral horn of the thoracic cord of the cat by preembbeding immunocytochemical method using SP antiserum. Methods: Five adults cats of either sex were used and deeply anesthetized by intramuscular injection of ketamine. After removal of the spinal cord, samples of thoracic cord were taken and placed in fresh fixative at $4^{\circ}C$ for 2 hours. Transverse sections $50{\mu}m$ thick were processed using the preembbeding immunocytochemical method and incubated consecutively in the specific primary antibody and the 10% normal goat serum, the rabbit anti-substance P antiserum, the biotin-labelled goat anti-rabbit IgG and finally the avidin-biotin-peroxidase complex. The processed tissue sections were throughly washed and stained in the black with 1% uranyl acetate. Section were examined on a electron microscope. Results: 1) SP immunoreactive neurons were observed in the gray matter around central canal. 2) In lamina I and II SP immunoreactivity was observed in both myelinated and unmyelinated nerve fibers, but in ventral horn only in the unmyelinated nerve fibers. 3) SP immunoreactive axon terminals with small round and large dense core vesicles made chemical synapses onto the dendrites of motor neurons in the ventral horn. Conclusion: SP immunoreactive neurons might play an important role in modulation of motor neurons in the ventral horn of the thoracic cord of the cat.

• Journal of Korean Neurosurgical Society
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• 제40권6호
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• pp.428-433
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• 2006

Objective : We investigated the pattern of glucose uptake in meningiomas using $^{18}F$-fluoro-2-deoxy-D-glucose[FDG] PET/CT. It was hypothesized that the degree of glucose uptake in each tumor could predict the histologic grade. Methods : In 19 patients with meningiomas, the Ki-67 proliferative index, standardized uptake values[SUV] of FDG uptake, tumor to contralateral gray matter ratio[TGR] of SUV, tumor size, edema grade, vascular endothelial growth factor[VEGF] expression, histopathologic grade and the blood supply pattern were assessed. Results : Of the 19 meningiomas, 8 were meningothelial, 1 fibrous, 2 transitional, 1 psammomatous, 2 angiomatous, and 5 atypical. The tumor proliferative index of Ki-67, tumor size, and peritumoral edema were larger in the histopathologic grade-2 meninigiomas than in the grade-1 meningioma group. There were no significant differences in SUV and TGR between two groups. Tumor size and peritumoral edema were significantly larger in VEGF-positive tumors than in negative tumors. Conventional angiography was performed in 12 patients. Dural supply was noted predominantly in 2 patients. Four patients had mainly pial cortical supply patterns. In tumors with more pial supply, VEGF was more frequently positive. There was a significant relation between SUV and Ki-67 and between SUV and peritumoral edema. Conclusion : We found FOG uptake in meningiomas is associated with proliferative potential, however, no clear limits of SUV and TGR can be set to distinguish between grade-1 and grade-2 meningiomas, which makes the assessment of malignancy grade using PET scan metabolic imaging difficult in individual cases.

• BMB Reports
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• 제39권4호
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• pp.400-405
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• 2006

A 16-month old boy was referred to our hospital for evaluation of recurrent generalized tonic clonic seizures. Metabolic evaluation revealed significant hyperammonemia ($1,112\;{\mu}g/dl$). Amino acid/acylcarnitine screening using tandem mass spectrometry showed markedly increased plasma levels of citrulline ($1,350\;{\mu}M/l$) with undetectable levels of arginine and arginosuccinic acid. Urinary excretion of citrulline was markedly increased ($38,617\;{\mu}M/g$ creatinine). Brain MRI findings showed diffuse high-signal intensity lesions, that involved gray and white matter in both frontal lobes and insula with edematous changes; these findings were consistent with the acute stage of citrullinemia (CTLN). Mutation analysis of the argininosuccinate synthetase (ASS) gene, in this patient, showed a Gly324Ser mutation in exon 13, and a 67-bp duplication mutation in exon 15 (c.1128-6_1188dup67). The patient was confirmed as having late-onset CTLN1 and treated with anticonvulsants, lactulose enema, protein restricted diet and arginine. Here we describe a case of late-onset CTLN1 in a patient by biochemical analyses and ASS gene mutation confirmation. This is the first report of a Korean patient with late-onset CTLN1 confirmed by ASS gene mutation identification.

• The Korean Journal of Physiology and Pharmacology
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• 제2권1호
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• pp.9-19
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• 1998

The present study was primarily carried out to characterize the properties of the spinomesencephalic tract (SMT) neurons that project from the upper cervical spinal segments to the midbrain. It was also investigated whether these neurons received convergent afferent inputs from other sources in addition to cervical inputs. Extracellular single unit recordings were made from neurons antidromically activated by stimulation of midbrain. Recording sites were located in lamina $I{\sim}VIII\;of\;C1{\sim}C3$ segments of spinal cord. Receptive field (RF) and response properties to mechanical stimulation were studied in 71 SMT neurons. Response profiles were classified into six groups: complex (Comp, n=9), wide dynamic range (WDR, n=16), low threshold (LT, n=5), high threshold (HT, n=6), deep/tap (Deep, n=10), and non- responsive (NR, n=25). Distributions of stimulation and recording sites were not significantly different between SMT groups classified upon their locations and/or response profiles. Mean conduction velocity of SMT neurons was $16.7{\pm}1.28\;m/sec$. Conduction velocities of SMTs recorded in superficial dorsal horn (SDH, n=15) were significantly slower than those of SMTs recorded in deep dorsal horn (DDH, n=18), lateral reticulated area (LRA, n=21), and intermediate zone and ventral horn (IZ/VH, n=15). Somatic RFs for SMTs in LRA and IZ/VH were significantly larger than those in SDH and DDH. Five SMT units (4 Comps and 1 HT) had inhibitory somatic RFs. About half (25/46) of SMT units have their RFs over trigeminal dermatome. Excitabilities of 5/12 cells and 9/13 cells were modulated by stimulation of ipsilateral phrenic nerve and vagus nerve, respectively. These results suggest that upper cervical SMT neurons are heterogenous in their function by showing a wide range of variety in location within the spinal gray matter, in response profile, and in convergent afferent input.

• The Korean Journal of Pain
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• 제11권2호
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• pp.182-193
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• 1998

Background: Ciliary neurotrophic factor (CNTF), identified as a survival factor for developing peripheral neurons is upregulated by reactive astrocytes in the traumatized tissue and in areas of terminal degeneration after a brain lesion. But in the spinal cord, CNTF is expressed in the non-astrocytic phenotypic, maybe oligodendrocytes. The present study was undertaken to determine the upregulation of CNTF expression in reactive astrocytes following spinal cord lesion in the rat. Methods: Unilateral incision of the dorsal funiculus at the thoracic level was performed and rats were sacrificed on days 3, 7, 14 and 28 postlesion. Western blot analysis, immunocytochemical analysis and double immunofluorescence for CNTF and glial fibrillary acidic protein (GFAP) were performed after spinal cord lesion. Results: A major band with 24 kDa and additional band of higher molecular weight form were detectable, and the intensity of the 24 kDa immunoreactive band increased up to 14 days postlesion and decreased toward laminectomized control values. CNTF immunoreactivity was markedly upregulated in the injured dorsal funiculus and adjacent gray matter. The time course of CNTF expression is coincident with the appearance of reactive astrocytes in the injured spinal cord. Moreover, double immunofluorescence for CNTF and glial fibrillary acidic protein (GFAP) revealed that CNTF immunoreactivity was in GFAP immunoreactive astrocytes. Conclusions: These results show that CNTF upregulation occurred in reactive astrocytes following spinal cord lesion, and suggest a role for CNTF in the regulation of astrocytic responses after spinal cord injury.