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Surgical Outcomes and Complications Following All Posterior Approach for Spinal Deformity Associated with Neurofibromatosis Type-1

  • Park, Byoung-Joo;Hyun, Seung-Jae;Wui, Seong-Hyun;Jung, Jong-Myung;Kim, Ki-Jeong;Jahng, Tae-Ahn
    • Journal of Korean Neurosurgical Society
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    • v.63 no.6
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    • pp.738-746
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    • 2020
  • Objectives : The purpose of this study was to evaluate surgical outcomes and complications of spinal deformity associated with neurofibromatosis type-1 (NF-1). Methods : From 2012 to 2018, patients suffering from spinal deformity associated with NF-1 who underwent surgical correction were identified. Demographic data and radiographic measures were retrospectively reviewed. Pre- and postoperative whole spine radiograph images were used to determine both coronal and sagittal Cobb angles. All of patients underwent 3-dimentional computed tomographic scan and magnetic resonance imaging scan to confirm dystrophic features. For evaluation of clinical outcomes, we surveyed the pre- and postoperative scoliosis research society-22r (SRS-22r) score. Results : Seven patients with spinal deformity associated with NF-1 were enrolled in this study. The mean age of patients was 29.5±1.2 years old. The mean follow-up period was 2.8±1.4 years. The apex of the deformity was located in cervicothoracic (n=1), thoracic (n=4), and lumbar region (n=2). Most patients have poor bone quality and decreased bone mineral density with average T-score of -3.5±1.0. All patients underwent surgical correction via posterior approach. The pre- and postoperative mean coronal and sagittal Cobb angle was 61.6±22.6° and 34.6±38.1°, 56.8±18.5° and 40.2±9.1°, respectively. Mean correction rate of coronal and sagittal angle was 44.7% and 23.1%. Ultimate follow-up SRS-22r score (average score, 3.9±0.4) improved comparing to preoperative score (average score, 3.3±0.9). Only one patient received revision surgery due to rod fracture. No serious complication occurred, such as neurological deficit, and viscerovascular injury. Conclusion : The surgical correction of patients having spinal deformity associated with NF-1 is challenging, however the radiographic and clinical outcomes are satisfactory. The all posterior approach can be a safe and effective surgical option for patients having dystrophic curves associated with NF-1.

Extent of Hyperostotic Bone Resection in Convexity Meningioma to Achieve Pathologically Free Margins

  • Fathalla, Hussein;Tawab, Mohamed Gaber Abdel;El-Fiki, Ahmed
    • Journal of Korean Neurosurgical Society
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    • v.63 no.6
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    • pp.821-826
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    • 2020
  • Objective : Hyperostosis in meningiomas can be present in 4.5% to 44% of cases. Radical resection should include aggressive removal of invaded bone. It is not clear however to what extent bone removal should be carried to achieve pathologically free margins, especially that in many cases, there is a T2 hyperintense signal that extends beyond the hyperostotic bone. In this study we try to investigate the perimeter of tumour cells outside the visible nidus of hyperostotic bone and to what extent they are present outside this nidus. This would serve as an initial step for setting guidelines on dealing with hyperostosis in meningioma surgery. Methods : This is a prospective case series that included 14 patients with convexity meningiomas and hyperostosis during the period from March 2017 to August 2018 in two university hospitals. Patients demographics, clinical, imaging characteristics, intraoperative and postoperative data were collected and analysed. In all cases, all visible abnormal bone was excised bearing in mind to also include the hyperintense diploe in magnetic resonance imaging (MRI) T2 weighted images after careful preoperative assessment. To examine bony tumour invasion, five marked bone biopsies were taken from the craniotomy flap for histopathological examinations. These include one from the centre of hyperostotic nidus and the other four from the corners at a 2-cm distance from the margin of the nidus. Results : Our study included five males (35.7%) and nine females (64.3%) with a mean age of 43.75 years (33-55). Tumor site was parietal in seven cases (50%), fronto-parietal in three cases (21.4%), parieto-occipital in two cases (14.2%), frontal region in one case and bicoronal (midline) in one case. Tumour pathology revealed a World Health Organization (WHO) grade I in seven cases (50%), atypical meningioma (WHO II) in five cases (35.7%) and anaplastic meningioma (WHO III) in two cases (14.2%). In all grade I and II meningiomas, bone biopsies harvested from the nidus revealed infiltration with tumour cells while all other bone biopsies from the four corners (2 cm from nidus) were free. In cases of anaplastic meningiomas, all five biopsies were positive for tumour cells. Conclusion : Removal of the gross epicentre of hyperostotic bone with the surrounding 2 cm is adequate to ensure radical excision and free bone margins in grade I and II meningiomas. Hyperintense signal change in MRI T2 weighted images, even beyond visible hypersototic areas, doesn't necessarily represent tumour invasion.

Chlorogenic Acid Isomers from Sorbus commixta of Ulleung Island Origin and Their Inhibitory Effects against Advanced Glycation End Product (AGE) Formation and Radical Scavenging Activity (울릉 마가목의 클로로겐산 이성체의 최종당화산물의 생성 저해 및 라디칼 소거 활성)

  • Kim, Tae Hoon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.8
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    • pp.1208-1213
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    • 2016
  • Advanced glycation end product (AGE) formation and reactive oxygen species are potential therapeutic targets for the prevention of diabetic nephropathy and other pathogenic complications. Activity-guided isolation of an ethylacetate-soluble portion of 80% methanolic extract from fruits of Sorbus commixta of the Ulleung Island origin using AGE formation inhibition assay led to the isolation and identification of three caffeoylquinic acid derivatives of a previously known structure, 3-O-caffeoylquinic acid (neochlorogenic acid; 1), 4-O-caffeoylquinic acid (cryptochlorogenic acid; 2), and 5-O-caffeoylquinic acid (chlorogenic acid; 3). The structures of these compounds were confirmed by interpretation of nuclear magnetic resonance and mass spectrometry data. Among the isolates, the major metabolite, neochlorogenic acid (1) showed the most potent inhibitory effect against AGE formation with an $IC_{50}$ value of $167.5{\pm}3.5{\mu}M$. Furthermore, all isolated chlorogenic acid isomers were evaluated for their radical scavenging activity against peroxynitrite, and structurally related isomers 1, 2, and 3 exhibited potent inhibitory effects in this radical scavenging assay. This result suggests that the monocaffeoyl quinic acid derivatives isolated from S. commixta might be beneficial for the regulation of diabetic complications and related diseases.

Analysis of metabolomic patterns in thoroughbreds before and after exercise

  • Jang, Hyun-Jun;Kim, Duk-Moon;Kim, Kyu-Bong;Park, Jeong-Woong;Choi, Jae-Young;Oh, Jin Hyeog;Song, Ki-Duk;Kim, Suhkmann;Cho, Byung-Wook
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.11
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    • pp.1633-1642
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    • 2017
  • Objective: Evaluation of exercise effects in racehorses is important in horseracing industry and animal health care. In this study, we compared metabolic patterns between before and after exercise to screen metabolic biomarkers for exercise effects in thoroughbreds. Methods: The concentration of metabolites in muscle, plasma, and urine was measured by $^1H$ nuclear magnetic resonance (NMR) spectroscopy analysis and the relative metabolite levels in the three samples were compared between before and after exercise. Subsequently, multivariate data analysis based on the metabolic profiles was performed using orthogonal partial least square discriminant analysis (OPLS-DA) and variable important plots and t-test was used for basic statistical analysis. Results: From $^1H$ NMR spectroscopy analysis, 35, 25, and 34 metabolites were detected in the muscle, plasma, and urine. Aspartate, betaine, choline, cysteine, ethanol, and threonine were increased over 2-fold in the muscle; propionate and trimethylamine were increased over 2-fold in the plasma; and alanine, glycerol, inosine, lactate, and pyruvate were increased over 2-fold whereas acetoacetate, arginine, citrulline, creatine, glutamine, glutarate, hippurate, lysine, methionine, phenylacetylglycine, taurine, trigonelline, trimethylamine, and trimethylamine N-oxide were decreased below 0.5-fold in the urine. The OPLS-DA showed clear separation of the metabolic patterns before and after exercise in the muscle, plasma, and urine. Statistical analysis showed that after exercise, acetoacetate, arginine, glutamine, hippurate, phenylacetylglycine trimethylamine, trimethylamine N-oxide, and trigonelline were significantly decreased and alanine, glycerol, inosine, lactate, and pyruvate were significantly increased in the urine (p<0.05). Conclusion: In conclusion, we analyzed integrated metabolic patterns in the muscle, plasma, and urine before and after exercise in racehorses. We found changed patterns of metabolites in the muscle, plasma, and urine of racehorses before and after exercise.

A Comparison of Accuracy between MRI and Arthroscopic Finding in the Diagnosis of Acute ACL Tear (급성 전방십자인대 손상의 진단에 있어 관절경 소견과의 비교분석을 통한 자기공명영상의 유용성)

  • Choi, Chong-Hyuk;Yoon, Han-Kook;Kim, Bo-Ram;Yoon, Choon-Sik
    • Journal of the Korean Arthroscopy Society
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    • v.9 no.1
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    • pp.46-50
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    • 2005
  • Purpose: The purpose of this study is to evaluate the accuracy of magnetic resonance imaging (MRI) in the diagnosis of acute anterior cruciate ligament (ACL) injury and its tear pattern in comparison with arthroscopic finding. Materials and Methods: Sixty consecutive patients with acute ACL injury were taken NRI followed by arthroscopic examination between January 2002 and June 2004. MRI findings were reviewed according to the presence of ACL discontinuity, diffuse swelling or thickening, focal edema, collapse on distal end, and any combined tear. The pathologic findings were then confirmed arthroscopically. The diagnostic accuracy of MRI on ACL tear pattern was analyzed by obtaining its positive predictive value. Results: All fifty two cases with presence of discontinuity on MRI showed ACL rupture arthroscopically. The location of ACL tear, diffuse swelling and focal edema on MRI also corresponded with arthroscopic findings respectively. However, the diagnostic accuracy of MRI was relatively lower in the presence of other ACL patterns such as collapses and combined tear. Conclusion: Preoperative MRI findings seem to be in accordance with arthroscopic findings and is significantly accurate in detection of location and diffuse swelling and focal edema of ACL tear.

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Arthroscopic Release of the Extensor Carpi Radialis Brevis Tendon for Chronic Recalcitrant Lateral Epicondylitis (만성 불응성 외 상과염에서 시행한 관절경적 단 요 수근 신건 유리술)

  • Ku, Jung Hoei;Hwang, Tae Hyok;Lee, Jung Su;Cho, Hyung Lae;Kim, Jung Woo
    • Journal of the Korean Arthroscopy Society
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    • v.16 no.2
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    • pp.140-146
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    • 2012
  • Purpose: The objective of this study was to assess the clinical outcome of arthroscopic release of the extensor carpi radialis brevis (ECRB) tendon in chronic recalcitrant lateral epicondylitis and tried to determine any prognostic factors. Materials and Methods: A retrospective review of 24 patients with lateral epicondylitis treated by arthroscopic ECRB release was performed. Outcome measures included a patient self rating and visual analog scale (VAS). Functional evaluation was made with Quick-disabilities of the arm, shoulder and hand (DASH) score system to identify preoperative factors that might be associated with the outcomes. Results: Twenty one (88%) elbows received benefit from the procedure. A mean preoperative VAS pain score and the mean Quick-DASH were significantly improved at final follow up. Age, sex, dominant arm and duration of symptom, presence of capsular tear or calcification did not correlate significantly with the clinical outcome. Three of four patients without T2-weighted high signal focus of the ECRB origin on preoperative magnetic resonance imaging (MRI) showed higher Quick-DASH score. Conclusion: Arthroscopic release of the ECRB is an effective option for chronic recalcitrant lateral epicondylitis. Lack of high signal focus on preoperative MRI is significantly associated with a poor surgical outcome and a considerable factor for the proper surgical indication.

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Restoration of the bell pavilion of King Song-Dok Bell with a view of its acoustical characteristics (성덕대왕 신종의 음향적 특성을 고려한 종각복원의 고찰)

  • Haan, Chan-Hoon
    • The Journal of the Acoustical Society of Korea
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    • v.37 no.5
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    • pp.378-386
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    • 2018
  • The present paper suggests the original form of the bell pavilion for the King Song-Dok bell which is one of the precious national treasure of Korea. In order to this, many literatures were reviewed including both historical and acoustical references. As the results, the model of the bell pavilion for the King Song-Dok bell is suggested as follows considering acoustical characteristics of the King Song-Dok bell and the traditional Korean bells ; 1) The bell pavilion has the rumbling puddle beneath the bell on the ground floor for resonance of sound 2) Many lumbers are used for columns and beams rather than boards since natural frequencies of the bell are 64 Hz and 168 Hz so that the sound absorption of the low frequency sound may not be occurred. 3) Only some boards may be used for the area between upper and middle molding of lintel in order to prevent of direct sunlight and sea breeze since this type of structure were used for bell pavilion of the same age. 4) Square form with the odd number of 3 or 5 Kans is adopted for bell pavilion considering the weight and the size of the bell which had been used traditionally 5) Finally, half-hipped structure is used for the roof of the bell pavilion which was the predominant form of the age.

A COMPARATIVE STUDY ONMAGNETIC RESONANCE IMAGE AND SECTOGRAPH OF HUMAN TNJ (악관절의 자기공명영상과 시상단층 방사선촬영상에 관한 비교연구)

  • Lee, Sung-Bok;Choi, Dae-Gyun;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.31 no.2
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    • pp.249-270
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    • 1993
  • For understanding of anatomy, physiology, and diseases of human TMJ, it is required to evaluate quantitatively the movement of the disc and condyle head of mandible. The histologic section of cadaver TMJ were examined, and the magnification of the MR image and its details of anatomy were evaluated. And then a quantitative analytic method, by comparing the Sectograph and the MR image of vital human TMJ, was proposed. For this study, 15 subjects(Male, 24~35years) were selected from a prosthodontic examination randomly, and each subject’s five interocclusal rubber registration records were made on the ICP, and 5, 10, 15, and 20mmjaw opening positions. All subjects were radiographed with a Denar Quint Sectograph Image System(Denar Corp., USA), and imaged with a MRP-20EX MR Image System(0.2T, Permanent Magnet Type, Hitachi Medical Corp., Japan) using an 100mm diameter bilateral type surface coil. These images were traced on the acetate tracing paper, and analyzed In this study, the findings led to the following conclusions. 1. In comparison of the histologic section of autopsy specimen with the MR image at the same section, the size(dimension) of MR image was 70% of the real one. It was possible to recognize the shape of articular disc, anterior and posterior attachments, and adjacent soft tissues, because of the excellent reproducibility of anatomical structure. 2. When we compared the amount of joint space on MR image with that of joint space on sectograph, the amount of joint space on sectograph was significantly greater than that of joint space on MR image, except at the top of condylar head. 3. The position of minimum joint space on sectograph at intercuspal position didn't coincide with the middle position of articular disc on MR image, and was approximately in the anterior third of posterior band of articular disc. 4. The amount of condylar movement on MR image at opening movement was greater than that of articular disc movement. From Intercuspal position to 5mm jaw-opening movement, the condylar movement showed hinge one, and over the range 5mm jaw-opening it suggested hinge & translatory one. 5. In terms of area variation of articular disc measured on MR image in sagittal plane, the area of posterior band increased with increasing the amount of Jaw opening, but the area of anterior band decreased conversely.

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Microvascular Decompression for Hemifacial Spasm Associated with Vertebrobasilar Artery

  • Kim, Joo-Pyung;Park, Bong-Jin;Choi, Seok-Keun;Rhee, Bong-Arm;Lim, Young-Jin
    • Journal of Korean Neurosurgical Society
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    • v.44 no.3
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    • pp.131-135
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    • 2008
  • Objective : Hemifacial spasm (HFS) is considered as a reversible pathophysiological condition mainly induced by continuous vascular compression of the facial nerve root exit zone (REZ) at the cerebellopontine angle. As an offending vessel, vertebrobasilar artery tends to compress much more heavily than others. The authors analyzed HFS caused by vertebrobasilar artery and described the relationships between microsurgical findings and clinical courses. Methods : Out of 1,798 cases treated with microvascular decompression (MVD) from Jan. 1980 to Dec. 2004. the causative vessels were either vertebral artery or basilar artery in 87 patients. Seventy-nine patients were enrolled in this study. Preoperatively, computed tomography (CT) or brain magnetic resonance (MR) imaging with 3-dimentional short range MR technique was performed and CT was checked immediately or 2-3 days after anesthetic recovery. The authors retrospectively analyzed the clinical features. the compression patterns of the vessels at the time of surgery and treatment outcomes. Results : There were 47 were male and 32 female patients. HFS developed on the left side in 52 cases and on the right side in 27. The mean age of onset was 52.3 years (range 19-60) and the mean duration of symptoms was 10.7 years. Many patients (39 cases; 49.1%) had past history of hypertension. HFS caused only by the vertebral artery was 8 cases although most of the other cases were caused by vertebral artery (VA) in combination with its branching arteries. Most frequently, the VA and the posterior inferior cerebellar artery (PICA) were the simultaneous causative blood vessels comprising 32 cases (40.5%). and in 27 cases (34.2 %) the VA and the anterior inferior cerebellar artery (AICA) were the offenders. Facial symptoms disappeared in 61 cases (77.2%) immediately after the operation and 68 cases (86.1%) showed good outcome after 6 months. Surgical outcome just after the operation was poor in whom the perforators arose from the offending vessels concurrently (p<0.05). Conclusion : In case where the vertebral artery is a cause of HFS, commonly branching arteries associated with main arterial compression on facial REZ requires more definite treatment for proper decompression because of its relatively poor results compared to the condition caused by other vascular compressive origins.

Design and Fabrication of Modified Monopole Antenna for Wireless USB Dongle with WLAN system Applications (WLAN 시스템 적용 가능한 무선 USB 동글용 변형된 모노폴 안테나의 설계 및 제작)

  • Lee, Yeong-Seong;Mun, Seung-Min;Kim, Gi-Rae;Yoon, Joong-Han
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.10
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    • pp.2223-2231
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    • 2015
  • In this paper, we propose a built-in antenna for wireless USB dongle which has a modified structure from the existing planar monopole antenna. The proposed antenna implemented a dual-band characteristic by inserting Strip1, Strip2, Strip3 into the monopole structure combined with 'n' shape and feeded 50-Ω using coaxial cable. The antenna is designed on an FR-4 substrate of which the dielectric constant is 4.6, and its overall size is 10 mm × 50 mm × 1mm. Based on the measurement results of the return loss, it was confirmed to satisfy the dual band resonance characteristics of 740 MHz (2.3 ~ 2.7 GHz) and 1,200 MHz (5.15 ~ 5.825 GHz) by -10 dB. In addition, we obtain the omni-directional radiation pattern measurements in the operating frequency bands, and the maximum gain of the proposed antenna has 2.26~3.81 dBi in the 2.4 GHz band and 2.21~5.79 dBi. in the 5.5 GHz band, respectively.