• Biomolecules & Therapeutics
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• 제29권6호
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• pp.615-629
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• 2021

An active compound, triterpene saponin, astersaponin I (AKNS-2) was isolated from Aster koraiensis Nakai (AKNS) and the autophagy activation and neuroprotective effect was investigated on in vitro and in vivo Parkinson's disease (PD) models. The autophagy-regulating effect of AKNS-2 was monitored by analyzing the expression of autophagy-related protein markers in SH-SY5Y cells using Western blot and fluorescent protein quenching assays. The neuroprotection of AKNS-2 was tested by using a 1-methyl-4-phenyl-2,3-dihydropyridium ion (MPP⁺)-induced in vitro PD model in SH-SY5Y cells and an MPTP-induced in vivo PD model in mice. The compound-treated SH-SY5Y cells not only showed enhanced microtubule-associated protein 1A/1B-light chain 3-II (LC3-II) and decreased sequestosome 1 (p62) expression but also showed increased phosphorylated extracellular signal-regulated kinases (p-Erk), phosphorylated AMP-activated protein kinase (p-AMPK) and phosphorylated unc-51-like kinase (p-ULK) and decreased phosphorylated mammalian target of rapamycin (p-mTOR) expression. AKNS-2-activated autophagy could be inhibited by the Erk inhibitor U0126 and by AMPK siRNA. In the MPP⁺-induced in vitro PD model, AKNS-2 reversed the reduced cell viability and tyrosine hydroxylase (TH) levels and reduced the induced α-synuclein level. In an MPTP-induced in vivo PD model, AKNS-2 improved mice behavioral performance, and it restored dopamine synthesis and TH and α-synuclein expression in mouse brain tissues. Consistently, AKNS-2 also modulated the expressions of autophagy related markers in mouse brain tissue. Thus, AKNS-2 upregulates autophagy by activating the Erk/mTOR and AMPK/mTOR pathways. AKNS-2 exerts its neuroprotective effect through autophagy activation and may serve as a potential candidate for PD therapy.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2865-2866
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• 2011

• 공업화학
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• 제17권5호
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• pp.532-538
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• 2006

탄화 및 활성화 조건을 매개체로 여러 등급의 Polyacrylonitrile (PAN)계 ACF (ACF : Activated Carbon Fiber)를 제조하여 최적의 비표면적을 나타내는 활성화 공정을 알아보았고, 가장 큰 비표면적을 갖는 PAN계 ACF에 대한 표면특성 및 독성가스 등에 대한 흡착특성을 분석하였다. 시험결과 활성화 온도가 증가할수록 비표면적이 증가하고 탄화 온도가 감소할수록 비표면적이 감소하였고, $900^{\circ}C$로 15 min간 탄화한 후 $900^{\circ}C$로 30 min간 활성화 공정을 거친 ACF가 $1204m^2/g$의 가장 높은 비표면적을 나타내었고 요오드 및 테러용 독성가스에 대한 흡착 성능시험 결과 기존의 흡착제보다 우수하였다. 또한 선택적 흡착을 위한 기능성을 부여하기 위하여 기존의 금속염을 침적하는 방법을 대체하여 비교적 안정화된 금속나노입자(Ag, Pt, Cu, Pd)를 제조하여 첨착하였고 이에 대한 표면특성 및 $SO_{2}$에 대한 흡착특성을 분석하였다. 금속나노입자 첨착 ACF에 대한 $SO_{2}$ 흡착성능 시험결과 Ag, Pt, Cu 나노입자를 첨착한 ACF는 무첨착 ACF의 파과시간(326 sec)과 비교 할 때 크게 변함이 없었으나 Pd 나노입자를 첨착한 ACF는 파과시간이 925 sec로 $SO_{2}$ 흡착성능이 매우 우수함을 알 수 있었다.

• 한국수소및신에너지학회논문집
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• 제17권2호
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• pp.234-240
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• 2006

Al film(135.5 nm thick) with Pd film(39.6 nm thick) on the top of it was made by thermal evaporation method. Hydrogen absorption of Al/Pd film was measured by quartz crystal microbalance(QCM) method at room temperature. The sample was activated by hydrogen absorption and desorption cycling at room temperature. Hydrogen was introduced into the film by increasing hydrogen gas pressure step by step up to 640 torr at room temperature. Hydrogen concentration reached up to 25% at $5{\sim}10$ torr. But at high pressure the concentration decreased. This strange tendency was not understood yet. Further study is needed to find out the mechanism of hydrogen absorption in Al in Al/Pd film.

• 한국표면공학회지
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• 제37권5호
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• pp.243-248
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• 2004

A palladium-nikel(Pd-Ni) alloy composite membrane has been fabricated on microporous nickel support formed with nickel powder. Plasma surface treatment process is introduced as pre-treatment process instead of HCI activation. Pd coating layer was prepared by dc magnetron sputtering deposition after $H_2$ plasma surface treatment. Palladium-nickel alloy composite layer had a fairly uniform and dense surface morphology. The membrane was characterized by permeation experiments with hydrogen and nitrogen gases at temperature of 773 K and pressure of 2.2psi. The hydrogen permeance was 6 ml/minㆍ$\textrm{cm}^2$ㆍatm and the selectivity was 120 for hydrogen/nitrogen($H_2$/$N_2$) mixing gases at 773 K.

• 한국표면공학회지
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• 제37권5호
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• pp.289-295
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• 2004

A dense palladium-nikel (Pd-Ni) alloy composite membrane has been fabricated on microporous nickel support mixed with submicron/micron nickel powder instead of mesoporous stainless steel support. Plasma treatment process is introduced as pre-treatment process instead of HCI activation. Pd-Ni alloy composite membrane prepared by electro plating was fairly a uniform and dense surface morphology. The membrane was characterized by permeation experiments with hydrogen and nitrogen gases at temperature 773 K and pressure 2.2 psi. The results showed that hydrogen ($H_2$) permeance was 27 ml/$\textrm{cm}^2$ㆍatmㆍmin and hydrogen/ nitrogen ($_H2$$N_2$) selectivity was 8 at 773 K.

• 대한한방내과학회지
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• 제41권1호
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• pp.59-68
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• 2020

Objectives: The purpose of this study was to investigate the current state of clinical trials for acupuncture treatment of Parkinson's disease (PD) using neuroimaging methods. Methods: We searched for clinical trial studies of acupuncture treatment for Parkinson's disease that used neuroimaging methods in the MEDLINE (PubMed) database. The identified studies were then selected manually based on inclusion criteria. We subsequently analyzed the characteristics of the selected articles and reviewed the neural substrates of acupuncture treatment in PD. Results: Eight studies were included. The most frequently applied modality for PD was functional MRI. The most frequently selected acupoint for PD was GV34. Several studies showed that acupuncture treatment could improve the symptoms of PD. Through the analysis, we demonstrated that the neuroimaging method could capture the neural substrates associated with PD and that acupuncture treatment may affect the activation of brain areas that are impaired in PD in a different way than sham acupuncture. Conclusions: Applying a neuroimaging method could be helpful in clinical trials of acupuncture treatment for PD, and more efforts should be made in this area.

• 미생물학회지
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• 제47권4호
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• pp.342-347
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• 2011

인체의 바이러스 감염 방어기전에서 T 림프구는 중요한 역할을 한다. 하지만, 만성 C형 간염 바이러스의 일차적 복제장소인 간염 환자의 간에서 분리된 HCV 특이 T 림프구는 심각한 기능결핍을 보인다. 이러한 T 림프구 기능결핍의 이유로는 PD-1, CTLA-4 등 면역억제 물질의 발현, 또는 간에서 특이적으로 유도되는 면역내성(immune tolerance)이 있으나, 간세포(hepatocytes)와 HCV 특이 T 림프구의 상호작용에 대해서는 명확하게 확립되어 있지 않다. 따라서 본 연구에서는 HLA(human leukocyte antigen) A2+ 간암세포주(human hepatoma cell line; huh7.5)가 항원제시(antigen presentation)를 통해 효과적으로 HCV 특이 T 림프구를 활성화시키며 간암세포주(huh7.5) 표면의 PD-L (program death ligand) 1 발현은 T림프구의 활성을 감소시켜 면역조절의 가능성이 있음을 시사하였다. 또한, HCV 특이 tetramer 반응은 T 림프구의 과도한 활성으로 자기사멸(apoptosis)의 경로에 있음을 caspase 3 활성으로 확인하였고, 역시 PD-L1의 발현이 T 림프구를 자기사멸(apoptosis)로부터 구제하여 caspase 3 활성이 감소하는 것을 확인하였다. 이는 PD-L1과 간성(liver) T 림프구 표면의 PD-1 결합이 T 림프구의 자기사멸을 막고, 또한 그 기능을 회복시켜 만성 C형 간염 치료에 응용될 수 있음을 시사한다.

• 한국수소및신에너지학회논문집
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• 제10권2호
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• pp.141-149
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• 1999

현재 수소저장 합금을 이용하여 2차전지의 음극으로 개발되고 있는 $AB_5$ type의 $(LM)Ni_{4.49}Co_{0.1}Mn_{0.205}Al_{0.205}$ 조성의 수소저장합금과 $AB_2$ type의 $Ti_{0.6}Zr_{0.4}V_{0.6}Ni_{1.4}$ 조성의 수소저장합금에 Pd를 0, 0.5, 1, 2 wt% 첨가한 조성을 진공 중에서 arc 용해를 하였다. 용해된 합금의 조직과 결정구조를 SEM, XRD로 조사하였다. Pd 가 첨가되었음에도 조직이나 결정구조의 변화는 보이지 않았다. 미세한 구리분말을 합금분말 대비 3:1로 첨가하여 pellet형태의 전극을 제조하여 전극특성을 조사한 결과 Pd 첨가에 따른 초기 활성화와 급속 충방전 특성은 크게 변하지 않았다. 그러나 싸이클 수명에 있어서는 Pd를 첨가한 전극들이 Pd를 첨가하지 않는 전극에 비해 우수하였다. $AB_5$ type 조성의 합금에서는 Pd를 2wt% 첨가한 전극, 그리고 $AB_2$ type 조성의 합금에서는 Pd를 0.5wt% 첨가한 전극에서 싸이클 특성이 가장 우수하게 나타났다.

• Journal of Electrochemical Science and Technology
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• 제8권3호
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• pp.215-221
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• 2017

The electroless plating process largely consists of substrate cleaning, seed formation (activator formation), and electroless plating. The most widely used activator in the seed formation step is Pd, and Sn ions are used to facilitate the formation of this Pd seed layer. This is problematic because the Sn ions interfere with the reduction of Cu ions during electroless plating; thus, the Sn ions must be removed by a hydrochloric acid cleaning process. This method is also expensive due to the use of Pd. In this study, Cu electroless plating was performed by forming a seed layer using a silver nanosol instead of Pd and Sn. The effects of the Ag nanosol concentration in the pretreatment solution and the pretreatment time on the thickness and surface morphology of the Cu layer were investigated. The degrees of adhesion to the substrate were similar for the electroless-plated Cu layers formed by conventional Pd activation and those formed by the Ag nanosol.