• Applied Biological Chemistry
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• 제51권2호
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• pp.124-128
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• 2008

개비자나무의 유효성분으로 알려진 homoharringtonine의 암세포주 K562에 대한 세포증식 저해 활성을 분석하였고, 마우스를 이용한 만성독성시험을 수행하였다. 총 약물처리 시간에 따른 최적 투여조건 결정 실험에서는 HHT를 9일, 6일, 3일 동안 매일 처리할 경우 각각 0.27, 0.37, 1.10mM의 농도에서 K562세포의 성장을 50% 감소시킴을 확인하였다. 기존 백혈병 치료제로 사용되고 있는 adriamycin과의 비교실험 결과 HHT는 K562 세포주에 대하여 adriamycin보다 낮은 저해율을 나타냈으나 비교적 근사한 값을 가졌다. HHT의 만성독성 실험 결과 혈액학적 지표 측정 실험에서 적혈구수(RBC)는 대조군과 HHT 투여군 사이에 유의적인 차이가 없었고, 간 기능 관련 효소의 혈액을 분석한 결과, 간 손상과 관련된 효소glutamate-oxalate-transferase, glutamate-pyruvate- transferase, cholesterol 및 alkaline phosphatase 모두 정상 범위에 있었다. 그러나 간 조직학적 검사에서는 HHT를 투여한 마우스의 간 조직에서 밴드형의 호중구를 침착시키는 것이 확인되었다.

• 한방안이비인후피부과학회지
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• 제24권2호
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• pp.1-15
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• 2011

Objective : Recently interest of fermented herb medicine has increased in Oriental medicine. Herb medicine fermented in a proper condition resultingly has better or new virtue by microbe. This study was designed to compare the anti-inflammatory effects of herbal decoction and fermented herbal decoction in Hwangnyeonhaedok-tang (Huanglian fiedu-tang; HHT). Methods : The effects of HHT and FHHT on anti-inflammation were measured by production of NO and pro-inflammatory cytokine productions including TNF-${\alpha}$ and IL-1${\beta}$, IL-6 in LPS induced RAW 264.7 cells. Results : 1. Cell viability in three doses of HHT extract (0.01, 0.05 and 0.10 mg/ml) and two doses of FHHT extract (0.01, 0.05 mg/ml) was more than 70％ and 80％ each. 2. In RAW 264.7 cells, LPS displayed significant stimulatory effects on the production of NO. However, both HHT, FHHT showed significant inhibitory effects on the production of NO. 3. Pre-treatment by HHT in a various concentrations (0.01, 0.05, 0.10, 0.50mg/ml) reduced the elevated production of TNF-${\alpha}$, IL-1${\beta}$, IL-1${\beta}$ mRNA, IL-6 mRNA. More than 0.05mg/ml concentrations of HHT reduced the production of IL-6. And TNF-${\alpha}$, IL-1${\beta}$ level of mouse serum reduced in a various dose(0.1, 0.5, 1.0g/kg). 4. Pre-treatment by FHHT in a various concentrations (0.01, 0.05, 0.10, 0.50mg/ml) reduced the elevated production of TNF-${\alpha}$. More than 0.05mg/ml concentrations of FHHT reduced the expression of TNF-${\alpha}$ mRNA. 0.1, 0.50mg/ml concentrations of FHHT reduced the production of IL-6. And IL-1${\beta}$ level of mouse serum reduced in a various dose(0.1, 0.5, 1.0g/kg). Conclusions : These results indicated that both HHT and FHHT could have anti-inflammatory capacity by inhibiting the production of NO and cytokines in vitro. But HHT has more strong anti-inflammatory effects than that of FHHT in broad outlines.

• Smart Structures and Systems
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• 제2권2호
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• pp.141-154
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• 2006

Recently, the Hilbert-Huang transform (HHT) has gained considerable attention as a novel technique of signal processing, which shows promise for the system identification and damage detection of structures. This study investigates the effectiveness and accuracy of the HHT method for the system identification and damage detection of structures through a series of experiments. A multi-degree-of-freedom (MDOF) structural model has been constructed with modular members, and the columns of the model can be replaced or removed to simulate damages at different locations with different severities. The measured response data of the structure due to an impulse loading is first decomposed into modal responses using the empirical mode decomposition (EMD) approach with a band-pass filter technique. Then, the Hilbert transform is subsequently applied to each modal response to obtain the instantaneous amplitude and phase angle time histories. A linear least-square fit procedure is used to identify the natural frequencies and damping ratios from the instantaneous amplitude and phase angle for each modal response. When the responses at all degrees of freedom are measured, the mode shape and the physical mass, damping and stiffness matrices of the structure can be determined. Based on a comparison of the stiffness of each story unit prior to and after the damage, the damage locations and severities can be identified. Experimental results demonstrate that the HHT method yields quite accurate results for engineering applications, providing a promising tool for structural health monitoring.

• Structural Engineering and Mechanics
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• 제36권6호
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• pp.697-714
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• 2010

This paper presents an improved version of the Hilbert-Huang transform (HHT) for the modal evaluation of structural systems or signals. In this improved HHT, a well-designed bandpass filter is used as preprocessing to separate and determine each mode of the signal for solving the inherent modemixing problem in HHT (i.e., empirical mode decomposition, EMD, associated with the Hilbert transform). A screening process is then applied to remove undesired intrinsic mode functions (IMFs) derived from the EMD of the signal's mode. A "best" IMF is selected in each screening process that utilizes the orthogonalization coefficient between the signal's mode and its IMFs. Through mode-by-mode signal filtering, parameters such as the modal frequency can be evaluated accurately when compared to the theoretical value. Time history of the identified modal frequency is available. Numerical results prove the efficiency of the proposed approach, showing relative errors 1.40%, 2.06%, and 1.46%, respectively, for the test cases of a benchmark structure in the lab, a simulated time-varying structural system, and of a linear superimposed cosine waves.

• Journal of Advanced Marine Engineering and Technology
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• 제36권2호
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• pp.258-266
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• 2012

음향방출(Acoustic Emission, AE) 시스템은 최근 조기 결함 검출 시스템 개발을 위해 적용되고 있으며, 그에 따르는 신호처리 기법에 대한 문제를 해결하기 위해 많은 노력을 기울이고 있다. 신호처리 기법 중 포락처리(Envelope analysis)가 베어링 결함 분석에 사용되고, Wavelet Transform은 기어 등의 결함 분석에 용이한 것으로 알려져 있다. 하지만 여전히 AE 신호를 위한 신호처리 기법은 불확실하다. 따라서 본 논문에서는 AE 시스템을 적용한 조기 결함 검출 시스템 개발을 위한 사전 연구로, AE 신호를 분석하기 위한 신호처리 기법으로 Hilbert Transform(HT)과 Hilbert-Huang Transform(HHT)에 대해 비교 분석한다. AE 신호는 피로시험을 통해 취득되었으며, 취득된 AE 신호를 두 신호처리 기법을 적용하여 주파수 및 시간 신호에 대해 분석하였다. HT에 비해 HHT가 시간-주파수 영역에 대해 결과를 나타내기 때문에 좀 더 명확한 특징을 보이는 데에 반해 신호처리 시간 및 필터링에 대한 단점을 보이고 있음을 확인하였다.

• Smart Structures and Systems
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• 제14권4호
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• pp.595-615
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• 2014

This study aims to investigate the relationship between structural damage and sensitivity indices using the Hilbert-Huang transform (HHT) method. Two damage detection indices are proposed: the ratio of bandwidth (RB), and the ratio of effective stiffness (RES). The nonlinear four bays multiple degree of freedom models with various predominant frequencies are constructed using the SAP2000 program. Adjusted PGA earthquake data (Japan 311, Chi-Chi 921) are used as the excitations. Next the damage detection indices obtained using the HHT and the fast Fourier transform (FFT) methods are evaluated based on the acceleration responses of the structures to earthquakes. Simulation results indicate that, the column of the 1 st floor is the first yielding position and the RB value is changed when the RES<90% in all cases. Moreover, the RB value of the 1 st floor changes more sensitive than those from the top floor. In addition, when the structural response is nonlinear (i.e., RES<100%), the RB and the RES curves indicate the incremental change in the HHT spectra. However, the same phenomenon can be found from FFT spectra only when the stiffness reduction is large enough. Therefore, the RB estimated from the smoothed HHT spectra is an effective and sensitive index for detecting structural damage.

• Journal of Korean Neurosurgical Society
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• 제63권4호
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• pp.504-512
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• 2020

Objective : An important factor during pituitary adenoma surgery is to preserve pituitary stalk (PS) as this plays a role in reduction of the risk of postoperative diabetes insipidus. The hypothalamic-hypophyseal tract (HHT) projects through the PS to the posterior pituitary gland. To reconstruct white matter fiber pathways, methods like diffusion tensor imaging (DTI) tractography have been widely used. In this report we attempted to predict the position of PS using DTI tractography and to assess its intraoperative correlation during surgery of pituitary adenomas. Methods : DTI tractography was used to tract the HHT in nine patients before craniotomy for pituitary adenomas. The DTI location of the HHT was compared with the PS position identified at the time of surgery. DTI fiber tracking was carried out in nine patients prior to the planned craniotomy for pituitary adenomas. In one patient, the PS could not be identified during the surgery. In the other eight patients, a comparison was made between the location of the HHT identified by DTI and the position of the PS visualized at the time of surgery. Results : The position of the HHT identified by DTI showed consistency with the intraoperative position of the PS in seven patients (88.9% concordance). Conclusion : This study shows that DTI can identify the position of the HHT and thus the position of the PS with a high degree of reliability.

• Journal of Oral Medicine and Pain
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• 제37권3호
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• pp.135-139
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• 2012

유전성출혈모세혈관확장증은 피부 및 점막에 있는 말단 혈관이 비정상적으로 확장된 모세혈관 확장증과 내부 장기, 특히 폐, 뇌, 간 부위의 동정맥기형 발생을 특징으로 하는 상염색체 우성 유전질환이다. 이 질병을 가진 환자들은 종종 오랜 시간 동안 진단이 되지 않은 채로 지내다가 생명을 위협할 수 있는 심각한 출혈, 뇌졸중, 뇌농양과 같은 합병증이 발생하기도 한다. 따라서 이 질환의 조기 진단 및 적절한 선별검사가 매우 중요하다. 유전성출혈모세혈관확장증의 조기 진단을 통해 증상 없이 존재하다 합병증을 유발할 수 있는 폐, 간, 뇌 부위의 동정맥기형에 대한 선별 검사를 시행함으로써 이 질병에 이환된 환자와 가족에 대한 예방적 관리가 가능하다. 피부 및 점막에 발생하는 모세혈관확장증은 특징적인 소견을 보이며 치과의사에 의해 쉽게 발견되므로 치과의사는 유전성출혈모세혈관확장증에 대해 잘 알고 조기 진단에 기여할 필요가 있다. 최근 이 질환으로 진단된 증례가 있어 문헌 고찰과 함께 보고하고자 한다.

• 한방재활의학과학회지
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• 제20권4호
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• pp.1-15
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• 2010

Objectives : This study was performed to evaluate the effects of Hwangryunhaedok-tang(Huanglianjiedu-tang HHT) water extract on locomotor dysfunction induced by spinal cord injury(SCI) in rats. Methods : SCI was induced by mechanical contusion following laminectomy of 10th thoracic vertebra in Sprague-Dawley rats. HHT was orally given once a day for 14 days after SCI. Neurological behavior was examined with the Basso-Beattie-Bresnahan locomotor rating scale. Tissue damage and nerve fiber degeneration were examined with cresyl violet and luxol fast blue staining. Using immunohistochemisty, cellular damage to neurons and nerve fibers were examined against Bax and MAP-2. As inflammatory response markers, iNOS and COX-2 expressions were also examined. Results : 1. HHT ameliorated the locomotor dysfunction of the SCI-induced rats. 2. HHT attenuated the reduction of motor neurons in the ventral horn of the SCI-induced rat spinal cord. 3. HHT significantly reduced the number of Bax positive cells in the peri-lesion of the SCI-induced rat spinal cord. 4. HHT attenuated the reduction of MAP-2 positive cells in the peri-lesion of the SCI-induced rat spinal cord. 5. HHT significantly reduced the number of iNOS and COX-2 positive cells in the peri-lesion of the SCI-induced rat spinal cord. Conclusions : These results suggest that HHT improves the locomotor dysfunction of SCI by protecting motor neurons from cell death through anti-inflammatory effect.

• 대한한의학회지
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• 제38권2호
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• pp.15-30
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• 2017

Objectives: Hwangryunhaedok-tang (HHT; Huanglianjiedu-tang, Orengedoku-to), a traditional herbal formula, is used for treating inflammation, hypertension, gastritis, liver dysfunction, cerebrovascular diseases, dermatitis and dementia. The objective of this study was to assess the sub-acute toxicity of HHT in Sprague-Dawley (SD) rats, and its effect on the activities of human microsomal cytochrome P450s (CYP450s) and UDP-glucuronosyltransferases (UGTs). Methods: Male and female SD rats were orally administered HHT once daily at doses of 0, 500, 1000 and 2000 mg/kg for 4 weeks. We analyzed mortality, clinical observations, body weight, food consumption, organ weights, urinalysis, hematology, serum biochemistry, and histopathology. The activities of major human CYP450s (CYP1A2, CYP3A4, CYP2B6, CYP2C9, CYP2C19, CYP2D6, and CYP2E1) and UGTs (UGT1A1, UGT1A4, and UGT2B7) were assessed using in vitro fluorescence- and luminescence-based enzyme assays, respectively. Results: No toxicologically significant changes related to the repeated administration of HHT were observed in both male and female SD rats. The no observed adverse effect level (NOAEL) value was more than 2000 mg/kg/day for both sexes. HHT inhibited the activities of human microsomal CYP1A2, CYP2C19, CYP2D6, and CYP2E1, whereas it weakly inhibited the activities of CYP2B6, CYP2C9, CYP3A4, and UGT1A1. In addition, HHT negligibly inhibited the activities of human microsomal UGT1A4 and UGT2B7 with $IC_{50}$ values in excess of $1000{\mu}g/mL$. Conclusions: Our findings indicate that HHT may be safe for repeated administration up to 4 weeks. In addition, these findings provide information on the safety and effectiveness of HHT when co-administered with conventional drugs.