• 한국세라믹학회지
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• 제50권3호
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• pp.231-237
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• 2013

Thermodynamic modeling of the $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ complex ferrite system has been adopted as a rational approach to establish routes to better synthesis conditions for pure phase $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ complex ferrite. Quantitative analysis of the different reaction equilibria involved in the precipitation of $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ from aqueous solutions has been used to determine the optimum synthesis conditions. The spinel ferrites, such as magnetite and substitutes for magnetite, with the general formula $MFe_2O_4$, where M= $Fe^{2+}$, $Co^{2+}$, and $Ni^{2+}$ are prepared by coprecipitation of $Fe^{3+}$ and $M^{2+}$ ions with a stoichiometry of $M^{2+}/Fe^{3+}$= 0.5. The average particle size of the as synthesized $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$, measured by transmission electron microscopy (TEM), is 14.2 nm, with a standard deviation of 3.5 nm the size when calculated using X-ray diffraction (XRD) is 16 nm. When $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ ferrite is annealed at elevated temperature, larger grains are formed by the necking and mass transport between the $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ ferrite nanoparticles. Thus, the grain sizes of the $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ gradually increase as heat treatment temperature increases. Based on the results of Thermogravimetric Analysis (TGA) and Differential Scanning Calorimeter (DSC) analysis, it is found that the hydroxyl groups on the surface of the as synthesized ferrite nanoparticles finally decompose to $Ni_{0.5}Zn_{0.4}Cu_{0.1}Fe_2O_4$ crystal with heat treatment. The results of XRD and TEM confirmed the nanoscale dimensions and spinel structure of the samples.

• 한국임상수의학회지
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• 제32권2호
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• pp.191-195
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• 2015

7년령, 중성화 수컷 고양이가 무기력과 식욕부진으로 내원하였다. 실험실 검사는 말초혈액 호중구에서 중등도의 퇴행성 변화, free 및 total thyroxine의 농도 감소 및 혈액배양에서 세균증식이 관찰되었다. 16S ribosomal RNA 및 heat shock protein 60 유전자 검사 결과 세균은 Enterobacter cloacae로 확인되었다. 항생제 최소억제농도 평가결과 16개 항생제에 대한 다약제 내성이 관찰되었다. 중합효소연쇄반응 및 시퀀싱 결과 $bla_{TEM-1}$, $bla_{CTX-M-15}$ 및 플라스미드 유래 $bla_{ACT-1}$ 유전자에 대한 양성 반응이 관찰되었으며, 결과적으로 확인된 세균이 광범위 beta-lactamase 및 ampC beta-lactamase를 합성하는 플라스미드를 보유한 것을 확인하였다. 환자는 1개월 간 항생제와 levothyroxine 치료를 받은 후 증상이 호전되었고, 치료 후 갑상선 기능검사와 혈액배양 결과 이상소견은 소실되었다. 이 증례는 고양이의 지역사회획득 다약제내성 E. cloacae에 의한 정상 갑상샘 질환 증후군의 첫 예이다. 신속한 진단과정과 적절한 항생제 선택에 의해 이환된 고양이는 패혈증으로부터 회복되었다.

• 한국정보전자통신기술학회논문지
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• 제13권3호
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• pp.212-218
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• 2020

인체에 고주파 에너지를 가하면 진동 폭이 매우 짧아서 직류 전류 이용 시 발생하는 전해질 화상이 일어나지 않으며 이온분자, 분극분자 등이 초당 4만 번 이상 진동을 하면서 마찰열로 전환되어 심부열을 발생시켜 모세혈관의 혈류량은 휴식 시 보다 4~5배 증가하여 산소, 영양물질, 항체, 백혈구 등 공급의 증가한다. 또한 진동 폭과 맥동기간이 매우 짧아 전기 화학적 반응이 일어나지 않으며 감각신경과 운동신경을 자극하지 않는 물리적 인자치료 방법이다. 본 연구에서는 고주파통증치료기를 사용하여 젊은 정상 성인을 대상으로 등장성운동을 시키고, 등장성 운동 시 근전도 데이터를 측정하여 운동신경 응답의 변화에 미치는 영향을 확인하여 재활치료 접목시키고자 하였다. 윗팔두갈래근의 등장성 운동을 실시할 때 발생되는 근전도 데이터와 운동 후 고주파통증치료기사용 후 측정된 근전도 데이터를 각각 RMS하여 t-검정을 통하여 검증을 실시하였으며, 남녀 모두 t값, p값이 유의수준(<.05) 보다 작게 나와 유의한 차이가 있다는 것을 확인하였다.

• 한국정보전자통신기술학회논문지
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• 제15권5호
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• pp.328-334
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• 2022

사람의 인지기능 중 주의력은 감각기관을 통해 방대한 자극 중 필요한 자극에만 의식을 집중하는 과정이다. 주의력은 실내 온도 등 노출 환경에 영향을 받는 것으로 알려져 있다. 스포츠 분야에서는 냉각 팩 등을 사용한 직접 전도 방식의 냉각이 광범위하게 사용되어 효과를 보고 있으나 전도에 의한 냉각이 주의력과 같은 인지 활동에 미치는 영향에 대해서는 알려진 바가 없다. 본 연구에서는 경추부 후면 부위에 특수 제작된 냉각 패드를 적용할 때 주의력에 미치는 영향을 살펴보기 위해 수행되었다. 40명의 피검사자를 네 집단으로 나누고 독서 및 산책 중 냉각 패드의 적용에 따라 주의력이 차이를 보이는지 살펴보았다. 주의력은 FAIR 주의력 검사를 통해 평가되었으며, 선택적 주의력을 의미하는 능력지수, 주의력의 정확도를 나타내는 통제지수, 균일한 주의력의 유지 기간을 나타내는 지속성지수에 대한 분산분석과 사후분석을 실시하였다. 결과적으로, 독서 및 학습 등 시각적 주의력이 지속적으로 요구되는 경우 냉각 패드의 적용을 통한 전도 냉각이 선택적 주의력을 확대시키고 균일한 주의력을 유지하는데 도움이 된다. 또한, 선택적 주의력의 향상과 균일한 주의력의 유지를 위해 가벼운 신체 활동이 도움이 된다. 다만 이 경우 전체 독서 시간의 감소를 전제로 하여야 한다.

• 한국방사선학회논문지
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• 제11권5호
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• pp.353-359
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• 2017

대표적인 저강도 초음파 자극 기술인 음파영동은 초음파의 물리적 진동과 온열 효과를 이용하여 약물을 인체 표피 내부로 전달시키는 기법이다. 음파영동법은 치료 약물 전달의 효율을 높일 수 있으며, 인슐린이나 지질 등 분자 크기가 비교적 큰 약물의 전달에도 효과적이라는 장점을 갖는다. 본 연구에서는 효율적인 음파영동 치료를 위하여 대면적 단일 진동소자와 치료 부위에 약물 이송 기능을 갖는 복합 구조 초음파 변환기 어셈블리를 제안하였다. 또한, 치료 부위의 온도를 상승 및 유지시킬 수 있는 변환기 어셈블리 구조를 제안하고 유효성을 평가하였다. 본 연구에서 제안된 변환기 어셈블리는 지속적으로 정량의 약물을 제공하고, 가온을 통하여 약물 전달을 보조함으로써 초음파를 이용한 음파영동 시술의 효율을 향상시킬 수 있을 것으로 사료된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.369-369
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• 2016

A nanostructure composite is a highly suitable substance for photoacoustic ultrasound generation. This allows an input laser beam (typically, nanosecond pulse duration) to be efficiently converted to an ultrasonic output with tens-of-MHz frequency. This type of energy converter has been demonstrated by using a carbon nanotube (CNT)-polydimethylsiloxane (PDMS) composite film that exhibit high optical absorption, rapid heat transition, and mechanical durability, all of which are necessary properties for high-amplitude ultrasound generation. In order to develop the CNT-PDMS composite film, a high-temperature chemical vapor deposition (HTCVD) method has been commonly used so far to grow CNT and then produce a CNT-PDMS composite structure. Here, instead of the complex HTCVD, we use a mixed solution of hydrophobic multi-walled CNT and dimethylformamid (DMF) and fabricate a solution-processed CNT-PDMS composite film over a spherically concave substrate, i.e. a focal energy converter. As the solution process can be applied over a large area, we could easily fabricate the focal transmitter that focuses the photoacoustic output at the moment of generation from the CNT-PDMS composite layer. With this method, we developed photoacoustic energy converters with a large diameter (>25 mm) and a long focal length (several cm). The lens performance was characterized in terms of output pressure amplitude for an incident pulsed laser energy and focal spot dimension in both lateral and axial. Due to the long focal length, we expect that the new lens can be applied for long-range ultrasonic treatment, e.g. biomedical therapy.

• 한방안이비인후피부과학회지
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• 제21권2호
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• pp.28-38
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• 2008

In traditional oriental medicine, Gentianae Radix has been used clinically for clearing away 'heat', removing dampness and purging fire in the liver and gall bladder. However, there has been a lack of studies regarding the effects of Gentianae Radix on the immunological activities. The present study was conducted to evaluate the effect of Gentianae Radix on the regulatory effects of cytokines and nitric oxide(NO) for the immunological activities in Raw 264.7 cells. After the treatment of Gentianae Radix MeOH extract, cell viability was measured by MTT assay, and NO production was monitored by measuring the nitrite content in culture medium. The expression of COX-2 and iNOS was determined by immunoblot analysis, and the content of levels of cytokines in media was analyzed by ELISA kit. Results provided evidence that Gentianae Radix inhibited the production of nitrite and nitrate (NO), inducible nitric oxide synthase (iNOS), $interleukin-l{\beta}$ $(IL-l{\beta})$ and IL-6, and the activation of phospholylation of inhibitor ${\kappa}B{\alpha}$ ($p-I {\kappa}B{\alpha}$) in Raw 264.7 cells activated with lipopolysaccharide (LPS). These findings suggest that Gentianae Radix can make anti-inflammatory effect, which may playa role in adjunctive therapy.

• 동의생리병리학회지
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• 제19권1호
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• pp.196-203
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• 2005

Gunggui-tang has been used for the therapy of blood disorders in Hangbang medicine for long time. Also, Glycyrrhiza uralensis has been used for deficientblood patterns with an irregular pulse or palpitations, coughing and wheezing, and heat or cold in the lungs. Melanogenesis is a physiological process resulting in the synthesis of melanin pigments. We investigated whether the water extract of Gunggui-tang plus G. uralensis inhibited melanogenesis in B16 melanoma cells. Because the molecular events connecting the regulation in tyrosinase activity remain to be elucidated, we also aimed to determine whether Gunggui-tang gamibang(GTG) affects tyrosinase at the gene activation level in the cells. First, we showed that GTG inhibited the tyrosinase promoter activity and further, down-regulated the tyrosinase protein activity in ${\alpha}-melanocyte-stimulating$ hormone $({\alpha}-MSH)-treated$ B16 melanoma cells. GTG also resulted in a decrease of melanin content in MSH-induced melanogenesis, indicating that GTG may be a useful drug in studying the regulation of melanogenesis. The pretreatment of GTG significantly prevented phosphotransferase activity of c-Jun N-terminal kinase (JNK1) and transcriptional activation of activating protein-1 (AP-1) in MSH-treated B16 melanoma cells. These findings indicate that GTG inhibits melanogenesis of B16 melanoma cells via suppression of phosphotransferase activity of JNK1 and transcriptional activation of AP-1.

• 대한한방내과학회지
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• 제21권5호
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• pp.869-872
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• 2000

Although there are a few reports concerning the hepatic injury of herbal medicine in western medicine, there is no reports concerning the hepatic injury of herbal medicine in oriental medicine. We experienced one case of the hepatic injury suggested toxic hepatitis (drug induced hepatitis) in the treatment of oriental medicine for cerebral infarction. We make a reports for the progress of treatment. One patient of Rt hemiparesis diagnosed cerebral infarction in Brain MRI was administered Taeumin Yuldahanso-tang, treated with physical therapy and improved in the state of Rt hemiparesis(Gr 2/3,4). In the course of treatment, the patient intermittently complained of general weakness, dizziness, pericephalic discomfort(頭不淸), nausea, both leg weakness so we changed Taeumin Yuldahanso-tang to Soyangin Dokwhaljiwhang-tang. Alter that, the patient complained of general weakness, abdominal discomfort, heat and fever($38.4^{\circ}C$). We recognized the elevated total bilirubin(1.7mg/dl), serum transaminase(AST534U/L ALT720U/L), serum gammg glutamyl transpepridase (GGT106mg/dl) and Alk phosphatase124U/L. In the abdominal ultrasonogram there is hepatomegaly (16.5cm). We supposed hepatic injury suggested toxic hepatitis(induced hepatitis) of herbal medicine. After we administered Saeng gan gunbi-tang for 2days and Alk phosphatase and GGT inadequately was elevated. After that, we stopped administering medicine and the serum transaminase, total bilirubin, serum gamma glutamyl transpeptidase and Alk phosphatase level was decreased. In the abdominal ultrasonogram there was no signal. In the case, we supposed that the changing Sasang constitution and Sasang herbal medicine may induce hepatic injury. We are suggesting the necessity of a test for the hepatic injury of herbal medicine.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.542-550
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• 2018

Heat shock protein 90 (Hsp90) is treated as a molecular therapeutic target for the prevention and treatment of cancer. Geldanamycin (GA) was the first identified natural Hsp90 inhibitor, but hepatotoxicity has limited its clinical application. Nevertheless, a new GA analog (WK-88-1) with the non-benzoquinone skeleton, obtained from genetically engineered Streptomyces hygroscopicus, was found to have anticancer activity against two human breast cancer cell lines. WK-88-1 produced concentration-dependent inhibition of cell proliferation, cell cycle arrest, and apoptosis in estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 cell lines. Detailed analysis showed that WK-88-1 downregulated some key cell cycle molecules (CDK1 and cyclin B1) and lead to $G_2/M$ cell cycle arrest. Further studies also showed that WK-88-1 could induce human breast cancer cell apoptosis by downregulating Hsp90 client proteins (Akt, p-Akt, IKK, c-Raf, and Bcl-2), decreasing the ATP level, increasing reactive oxygen species production, and lowering the mitochondrial membrane potential. Meanwhile, we discovered that WK-88-1 significantly decreased the levels of Her-2 and $ER-{\alpha}$ in MCF-7 cells but not in MDA-MB-231 cells. In addition, WK-88-1 significantly increased caspase-3, -8, and -9 activities and the cleavage of PARP in a concentration-dependent manner (with the exception of caspase-3 and PARP in MCF-7 cells). Taken together, our preliminary results suggest that WK-88-1 has the potential to play a role in breast cancer therapy.