• Biomolecules & Therapeutics
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• 제21권5호
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• pp.364-370
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• 2013

Resveratrol (trans-3,4'-trihydroxystillbene), a naturally occurring polyphenolic antioxidant found in grapes and red wine, elicits diverse biochemical responses and demonstrates anti-aging, anti-inflammatory, and anti-proliferative effects in several cell types. Previously, resveratrol was shown to regulate differentiation and inflammation in rabbit articular chondrocytes, while the direct production of nitric oxide (NO) in these cells by treatment with the NO donor sodium nitroprusside (SNP) led to apoptosis. In this study, the effect of resveratrol on NO-induced apoptosis in rabbit articular chondrocytes was investigated. Resveratrol dramatically reduced NO-induced apoptosis in chondrocytes, as determined by phase-contrast microscopy, the MTT assay, FACS analysis, and DAPI staining. Treatment with resveratrol inhibited the SNP-induced expression of p53 and p21 and reduced the expression of procaspase-3 in chondrocytes, as detected by western blot analysis. SNP-induced degradation of I-kappa B alpha ($I{\kappa}B-{\alpha}$) was rescued by resveratrol treatment, and the SN50 peptide-mediated inhibition of NF-kappa B (NF-${\kappa}B$) activity potently blocked SNP-induced caspase-3 activation and apoptosis. Our results suggest that resveratrol inhibits NO-induced apoptosis through the NF-${\kappa}B$ pathway in articular chondrocytes.

• 대한기계학회논문집B
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• 제27권11호
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• pp.1612-1617
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• 2003

Synchrotron X-ray micro imaging technique was employed to non-invasively monitor the water flow inside xylem vessels in a bamboo leaf. The phase contrast X-ray images clearly visualized plant anatomy and the rise of a water front inside the vessels. Consecutive X-ray images taken for 60 seconds revealed water rise kinetics against gravity in the xylem of a cut dry leaf taken from a bamboo tree. For the first time, traces of water rise, variation of contact angle between water and xylem wall as well as the internal structure of xylem were obtained. In xylem vessels, a repeating flow pattern has a typical flow velocity of 30.7$\mu\textrm{m}$/s and faster flow is established intermittently. It is concluded that the transmission type of X-ray micro imaging can be used as a powerful tool to investigate the ascent of sap in the xylem vessels at a resolution higher than that of MRI.

• 대한의용생체공학회:의공학회지
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• 제25권4호
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• pp.235-242
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• 2004

본 논문에서는 영역 성장법을 기반으로 자동적인 임계치 설정에 의하여 미세 석회화를 추출하는 방법을 제안하였다. 미세 석회화 후보 영역에서 임계치를 반복적으로 증가시키면서 국부 최대치 화소로부터 영역을 성장시키고 명암 대비와 에지 선예도가 최대일 때 최적의 임계치가 결정됨으로써, 실제 영상에 있어서 효과적으로 미세 석회화를 추출할 수 있었다. 총 299개의 미세 석회화에 대하여 81.5%의 TP(true positive) 비율과 1.1개의 평균 FP(false positive) 개수를 가지는 만족할 만할 결과를 얻었으며, 진단 방사선 전문의의 조기 유방암 진단을 위한 보조 역할이 될 수 있음을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제17권10호
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• pp.1638-1644
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• 2007

The effect of carbon sources on tacrolimus production by a mutant strain of Streptomyces clavuligerus CKD 1119, an isolate from soil, was examined. Among the carbohydrates and oils tested in this work, a mixed carbon source of soluble starch and com oil was the best. An analysis of the culture kinetics also showed that, in contrast to the carbohydrates, the com oil was consumed later in the antibiotic production phase, implying that the oil substrate was the principal carbon source for the biosynthesis of tacrolimus, and this was directly proven by experiments using $^{14}C$-glucose and $^{14}C$-oleate substrates. Furthermore, com oil induced the formation of lipase by the mutant strain, whereas the addition of glucose significantly repressed lipase activity. The lipase activity exhibited by the FK-506-overproducing mutants was also observed to be directly proportional to their tacrolimus yield, indicating that a high lipase activity is itself a crucial factor for tacrolimus production. A feasibility study with a 200-1 pilot-scale fermentor and the best strain (Tc-XII-15322) identified in this work revealed a high volumetric and specific productivity of about 495 mg/l and 0.34 mg/mg dry mycelium, respectively.

• Journal of Korean Neurosurgical Society
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• 제40권4호
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• pp.277-280
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• 2006

Extracerebral cavernous hemangiomas are rare vascular tumors that are very difficult to remove because of severe intraoperative bleeding. We report a case of 57-year-old male with extracerebral cavernous hemangioma with review of 126 cases in the literature. Patient presented with blurred vision, diplopia, numbness on the left side of his face. Magnetic resonance imaging revealed a well defined mass of $3{\times}4{\times}3cm$ size with heterogenous iso-or hypointensity on T1-weighted image showing strong homogenous contrast enhancement and marked hyperintensity on T2-weighted image. Digital subtraction angiography[DSA] revealed a faint tumor blush by feeders from the left internal carotid artery[ICA] and left external carotid artery[ECA] in the delayed phase. Even with profuse intratumoral bleeding, near total removal was achieved. In addition to preoperative neurologic deficits such as ophthalmoplegia, facial numbness in the V1-2 dermatomes, ptosis appeared postoperatively.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10495-10500
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• 2015

Background: To evaluate the effects of bufalin in A549 human lung adenocarcinoma epithelial cells in vitro and assess the underlying mechanisms. Materials and Methods: Human A549 non-small cell lung cancer (NSCLC) cells were treated with various concentrations of bufalin. Cell proliferation was measured by CCK-8 assay, apoptotic cell percentage was calculated by flow cytometry and morphological change was observed by inverted phase contrast microscopy/transmission electron microscopy. In addition, the membrane potential of mitochondria was detected by JC-1 fluorescence microscopy assay, and the related protein expression of cytochrome C and caspase-3 was analyzed by Western blotting. Results: Bufalin could inhibit the proliferation of A549 cells via induction of apoptosis, with the evidence of characteristic morphological changes in the nucleus and mitochondria. Furthermore, bufalin decreased the mitochondrial membrane potential with up-regulation of cytochrome C in the cytosol, and activation of caspase-3. Conclusions: Bufalin inhibits the proliferation of A549 cells and triggers mitochondria-dependent apoptosis, pointing to therapeutic application for NSCLC.

• 한국분말재료학회지
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• 제20권1호
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• pp.13-18
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• 2013

In the present study, we systematically investigated the effect of Mn addition on nitrogenation behavior and magnetic properties of Sm-Fe powders produced by reduction-diffusion process. Alloy powders with only $Sm_2(Fe,Mn)_{17}$ single phase were successfully produced by the reduction-diffusion process. The coercivity of $Sm_2(Fe,Mn)_{17}$ powder rapidly increased during nitrogenation and reached the maximum of 637 Oe after 16 hours. After further nitrogenation, it decreased. In contrast, the coercivity of $Sm_2Fe_{17}$ powder gradually increased during nitrogenation for 24 hours. The coercivity of $Sm_2(Fe,Mn)_{17}$ powder was higher than that of $Sm_2Fe_{17}$ powder at the same condition of nitrogenation. It was considered that the Mn addition facilitates the nitrogenation of $Sm_2Fe_{17}$ powder and enhances the coercivity.

• The Korean Journal of Physiology
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• 제24권1호
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• pp.15-26
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• 1990

Hemoglobin was purified from the outdated human red blood cells. Phospholipids were purified from egg yolk and stored in chloroform. The artificial red blood cells (hemosome) were prepared by encapsulation of hemoglobin with phospholipid mutilayer using rotary vacuum evaporator. The shape and size of hemosomes were measured by phase contrast microscope and image analyzer. The function of hemosomes was tested by measuring oxygen dissociation curve using blood gas analyzer. In order to test whether hemosomes are useful as blood substitute they were infused into rats of which one third of total blood were drawn. The results obtained are summarized at followings. 1) Hemosomes were spherical shape and their mean diameter was 0.7 um. 2) Oxygen dissociation curve of hemosomes showed the same figure as that of normal red blood cells. 3) All rats given 1/3 transfusion with hemosomes survived until sacrificed whereas three of four rats given 1/3 transfusion with saline died within 1 hour and the rest of them died within 24 hours.

• 한국재료학회지
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• 제5권2호
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• pp.197-202
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• 1995

저압 화학 기상증착법으로 제작한 비정질 실리콘의 표면 형태 및 결정 성장 과정을 증착조건과 열처리 조건의 변화에 따라 조사하였다. 비정질에서 결정으로 변화하는 전이온도인 570~$590^{\circ}C$에서 증착한 시편은 (311)조직의 거친 표면으로 성장하였다. 같은 증착 온도에서 두께가 두꺼울수록 다결정에서 비정질로 변화하였다. 증착하는 과정에서의 결정화는 기판에서부터 시작되지만, 진공상태를 그대로 유지하고 비정질 실리콘을 전이온도에서 열처리하면 표면 실리콘 원자가 이동하여 결정화하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2807-2811
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• 2015

Scorpion venom peptides recently have attracted attention as alternative chemotherapeutic agents that may overcome the limitations of current drugs, providing specific cytotoxicity for cancer cells with an ability to bypass multidrug-resistance mechanisms, additive effects in combination therapy and safety. In the present study, BmKn-2 scorpion venom peptide and its derivatives were chosen for assessment of anticancer activities. BmKn-2 was identified as the most effective against human oral squamous cells carcinoma cell line (HSC-4) by screening assays with an $IC_{50}$ value of $29{\mu}g/ml$. The BmKn-2 peptide killed HSC-4 cells through induction of apoptosis, as confirmed by phase contrast microscopy and RT-PCR techniques. Typical morphological features of apoptosis including cell shrinkage and rounding characteristics were observed in treated HSC-4 cells. The results were further confirmed by increased expression of pro-apoptotic genes such as caspase-3, -7, and -9 but decrease mRNA level of anti-apoptotic BCL-2 in BmKn-2 treated cells, as determined by RT-PCR assay. In summary, the BmKn-2 scorpion venom peptide demonstrates specific membrane binding, growth inhibition and apoptogenic activity against human oral cancer cells.