• The Korean Journal of Physiology and Pharmacology
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• v.9 no.6
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• pp.341-346
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• 2005

The mechanism underlying oxidant-induced intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) increase was studied in cultured bovine aortic endothelial cells (BAECs) using fura-2 AM. In the presence of 2 mM extracellular $Ca^{2+}$, the application of DTBNP ($20{\mu}M$), a membrane-permeable oxidant, caused an increase in $[Ca^{2+}]_i$, and DTT (2 mM) as a reductant completely reversed the effect of DTBNP. The $[Ca^{2+}]_i$ increase induced by DTBNP was also observed in an extracellular $Ca^{2+}$-free/2 mM EGTA solution, indicating the release of $Ca^{2+}$ from intracellular store(s). After endoplasmic reticulum was depleted by an $IP_3$-generating agonist, ATP ($30{\mu}M$) or an ER $Ca^{2+}$ pump inhibitor, thapsigargin ($1{\mu}M$), DTBNP-stressed BAECs showed an increase of $[Ca^{2+}]_i$ in $Ca^{2+}$-free/2 mM EGTA solution. Ratio-differences before and after the application of DTBNP after pretreatment with ATP or thapsigargin were $0.42{\pm}0.15$ and $0.49{\pm}0.07$, respectively (n=7), which are significantly reduced, compared to the control value of $0.72{\pm}0.07$ in a $Ca^{2+}$-free/2 mM EGTA solution. After the protonophore CCCP ($10{\mu}M$) challenge to release mitochondrial $Ca^{2+}$, the similar result was obtained. Ratio-difference before and after the application of DTBNP after pretreatment with CCCP was $0.46{\pm}0.09$ (n=7). Simultaneous application of thapsigargin and CCCP completely abolished the DTBNP-induced $[Ca^{2+}]_i$ increase. The above results together indicate that the increase of $[Ca^{2+}]_i$ by DTBNP resulted from the release of $Ca^{2+}$ from both endoplasmic reticulum and mitochondria.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.281-285
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• 2013

Purpose: To probe the role of FasL in cell apoptosis in oral squamous cell carcinomas (OSCCs). Methods: The expression of Fas/FasL was assessed in 10 cases of normal oral epithelium, 38 cases of OSCC and tumor infiltrating lymphocytes (TIL), and 11 cases of metastatic lymph nodes by immunohistochemistry. Apoptosis of tumor cells and TIL was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). FasL-induction of T cell apoptosis was tested by co-culture assay in vitro with SCC-9 and Jurkat T cells. Results: The 10 cases of normal oral epithelium all demonstrated extensive expression of Fas, the positive rate being largely down-regulated in OSCC (21/38) (P<0.05) compared to the normal (10/10). At the same time, the positive rate of FasL significantly increased in OSCC (P<0.05) especially those with lymph node metastasis (P<0.05). The positive rates of Fas in well and middle differentiated OSCC were higher than those in poor differentiated OSCC (P<0.05). The AI of tumor cells in Fas-positive OSCC was remarkably higher than that in Fas-negative OSCC (P<0.01), with a positive correlation between Fas expression and cell differentiation as well as apoptosis (r=0.68, P<0.01). The AI of tumor cells in FasL positive OSCC was remarkably lower than that in control while the AI of TIL was higher than in FasL negative OSCC (P<0.05). The AI of tumor cells reversely correlated with that of TIL (r = -0. 72, P<0.05). It was found that SCC-9 cells expressing functional FasL could induce apoptosis of Jurkat cells as demonstrated by co-culture assays. As a conclusion, it is evident that OSCC cells expressing FasL can induce apoptosis in Fas-expressing T cells. Conclusions: In progression of OSCC, expression of the Fas/FasL changes significantly. The results suggest that FasL is a mediator of immune privilege in OSCC and may serve as an marker for predicting malignant change in oral tissues.

• Therapeutic Science for Rehabilitation
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• v.4 no.2
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• pp.73-83
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• 2015

Objective: The purpose of this study was to examine the effect of the Spaced Retrieval Training (SRT) with Errorless learning on the elderly with Mild Cognitive Impairment (MCI)'s memory, Instrumental Activities Daily Living, Depression symptom. Methods: A single subject experimental research with ABA design was conducted in this study on the 78-years-old person who was enrolled in day-care center. The total experimental sessions were 16 which composed of 3 sessions for baseline, 10 sessions for intervention and 3 sessions for second baseline. K-Auditory Verbal Learning Test (K-AVLT) was measured for the memory each session. For the measurement of cognitive function, IADL, depression Symptom, Korean version of Montreal Cognitive Assessment (MoCA-K), Philadelphia Geriatric Center Instrumental Activities Daily Living (PGC IADL), Geriatric Depression Scale Korean Version (GDS-K) was measured at pre-post test. Results: Memory at the phase B was improved than Phase A. At the phase B, the scores trend was ascending, but after the intervention at the phase A', the scores trend was descending. The scores of MoCA-K were improved, PGC IADL were maintained, GDS-K were decreased. Conclusion: This results support the evidence of the SRT with EL on the elderly with MCI in the clinical setting. In the future, the correlation researches about MCI's memory and other functional factors will be needed for effective occupational therapy service.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.1
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• pp.66-74
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• 2018

In order to evaluate the precision degree of the blocks on the dock, the shipyards recently started to use the point cloud approaches using the 3D scanners. However, they hesitate to use it due to the limited time, cost, and elaborative effects for the post-works. Although it is somewhat traditional instead, they have still used the electro-optical wave devices which have a characteristic of having less dense point set (usually 1 point per meter) around the contact section of two blocks. This paper tried to expand the usage of point sets. Our approach can estimate the rework time to weld between the Pre-Erected(PE) Block and Erected(ER) block as well as the precision of block construction. In detail, two algorithms were applied to increase the efficiency of estimation process. The first one is K-mean clustering algorithm which is used to separate only the related contact point set from others not related with welding sections. The second one is the Concave hull algorithm which also separates the inner point of the contact section used for the delayed outfitting and stiffeners section, and constructs the concave outline of contact section as the primary objects to estimate the rework time of welding. The main purpose of this paper is that the rework cost for welding is able to be obtained easily and precisely with the defective point set. The point set on the blocks' outline are challenging to get the approximated mathematical curves, owing to the lots of orthogonal parts and lack of number of point. To solve this problems we compared the Radial based function-Multi-Layer(RBF-ML) and Akima interpolation method. Collecting the proposed methods, the paper suggested the noble point matching method for minimizing the rework time of block-welding on the dock, differently the previous approach which had paid the attention of only the degree of accuracy.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.84-94
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• 1991

The purpose of this study was to evaluate the influence of high does carbon tetrachloride($CCl_4$) on the hepatotoxic effect of dimethylnitrosamine(DMN) which induces acute hemorrhagic necrosis in liver. Rats were injected intraperitoneally DMN dissolved in physiologic saline by a dose of 40mg/kg. For changes related to $CCl_4$ pretreatment, rats were injected intraperitoneally $CCl_4$ dissolved in olive oil by a dose of 0.4mg/kg, and then injected DMN. The livers were extracted from the rats 3, 6, 12, 24, 48, 72, and 120 hours after $CCl_4$ and/or DMN injection. Liver tissues were examined with light and electron microscopes. The results were summarized as follows ; Light microscopic findings : Severe centrilobular hemorrhagic necrosis developed from 12 hours after injection of DMN and continued to 120 hours. On injection of DMN after $CCl_4$ pretreatment, Massive necrosis occurred early. But active regenerative changes were produced in 24 hours. In 120 hours, the liver recovered in almost normal appearance. The degree of necrosis in pretreated group was similar to that in DMN injection only, and the time of recovery was faster in preteated group. Electron microscopic findings ; The early change was mainly disorganization of RER in DMN injection, and clumping and vesicular dilatation of ER in injection of $CCl_4$. In pretreatment group the early change was similar in appearance with $CCl_4$ group, but severer in degree. According to the results, it was revealed that acute toxic effect of DMN was recovered more rapidly in pretreatment group. Thus it was suggested that $CCl_4$ had protective effect in DMN hepatotoxicity.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.903-907
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• 2015

Background: Among human epidermal growth factor receptor 2 (HER2)-positive breast cancer, more than half are also hormone receptor (HR)-positive. Although HR is a predictive factor for the efficacy of hormone therapy, there are still some uncertainties in regard to the effects on patients with HR-positive and HER2-positive metastatic breast cancers due to the potential resistance to hormone therapy caused by co-expression of HR and HER2. There are no clinical trials directly comparing the efficacy of hormonal therapy with chemotherapy. Materials and Methods: To examine the real-world effect of hormone therapy on patients with HR-positive and HER2-positive metastatic breast cancers, a cross-sectional study of a representative sample of the Chinese population was conducted. The study included 113 patients who received first-line and second-line palliative treatment between 2005 and 2010 in the Cancer Institute and Hospital, Chinese Academy of Medical Science. The effect of hormone therapy on overall survival (OS) was studied. Results: The patients who received hormone therapy (n=51) had better overall survival in contrast to those who received chemotherapy with anti-HER2 therapy (n=62) in first- or second-line treatment. The difference was of borderline statistical significance (51.8m vs 31.9m, p=0.065). In addition, the effect of hormone therapy did not differ significantly with other prognostic factors, including age (${\leq}50$ years or >50 years), disease free survival (${\geq}2$ years or < 2 years) and site of metastasis (visceral or bone/soft tissue). On multivariate analysis, administration of hormone therapy was associated with a trend toward a favorable prognosis (p=0.148, HR=0.693, 95%CI 0.422-1.139). Age more than 50 years was the sole independent harmful prognostic factor (p<0.001, HR=2.797, 95%CI 1.676-4.668). Conclusions: Our data suggest that hormonel therapy may improve outcomes of the patients with ER-positive and HER2-positive metastatic breast cancer.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.445-450
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• 2010

The aim of this study was to evaluate the effect according to the fiber type and combination on the reinforcement of heat-polymerized denture base resin. The heat-polymerized resin(Vertex RS, Dentimax, Netherlands) was used in this study. Glass fiber(GL; ER 270FW, Hankuk Fiber Glass, Korea), polyaromatic polyamide fiber(PA; aramid; Kevlar-49, Dupont, U.S.A.) and ultra high molecular weight polyethylene fiber(PE, polyethylene; P.E, Dong Yang Rope, Korea) were used to reinforce the denture base resin specimens. The final size of test specimen was $64mm{\times}10mm{\times}3.3mm$. The specimens of each group were stored in distilled water at $37^{\circ}C$ for 50 hours before measurement. The flexural strength and flexural modulus were measured by an universal testing machine(Z020, Zwick, Germany) at a crosshead speed of 5 mm/min in a three-point bending mode. In this study, all fibers showed reinforcing effects on denture base resin(p<0.05). In terms of flexural strength and flexural modulus, glass fiber 5.3 vol.% showed most effective reinforcing effect on heat polymerized denture base resin. For flexural modulus, PA/GL was the highest in denture base resin specimen for hybrid FRC using two combination (p<0.05). Glass fiber 5.3 vol.% and PA/GL are considered to be applied effectively in reinforcing the heat polymerized denture base resin.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.234-239
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• 1999

A Abstract Yttria-stabilized zirconia(YSZ) thin films were synthesized by plasma enhanced chemical vapor deposition process. $Zr[TMHD]_4$ $Y[TMHD]_3$ precursors and oxygen were used with the deposition temperature of $425^{\circ}C$ and rf power ranging 0-100 watt. Effects of the deposition parameters were studied by X-ray diffraction and thickness anal­ysis. YSZ thin films have cubic crystal structure with (200) orientation. From the results of EDX analysis, the converte ed content of TEX>$Y_2O_3$ was determined to be 0-36%, and the film thickness was increased with bubbling temperature which is considered to be due to increasing TEX>$Y_2O_3$ flux. The depth profiles of Zr, Y and 0 appeared relatively $\infty$nstant through film thickness. Columnar grains of $1000~2000\AA$ grew vertical to the substrate surface for the case of Ar carri­er gas. In case of He carrier gas, the grain size was observed to be about $1000~2000\AA$. X-ray diffraction data showed the increase of lattice constant with TEX>$Y_2O_3$ content. It was that the presence of the cracks formed during film deposition, partially released the stress generated by the increase of lattice constant.

• Safety and Health at Work
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• v.10 no.2
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• pp.229-236
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• 2019

Background: Emerging reports suggest the potential for adverse health effects from exposure to emissions from some additive manufacturing (AM) processes. There is a paucity of real-world data on emissions from AM machines in industrial workplaces and personal exposures among AM operators. Methods: Airborne particle and organic chemical emissions and personal exposures were characterized using real-time and time-integrated sampling techniques in four manufacturing facilities using industrial-scale material extrusion and material jetting AM processes. Results: Using a condensation nuclei counter, number-based particle emission rates (ERs) (number/min) from material extrusion AM machines ranged from $4.1{\times}10^{10}$ (Ultem filament) to $2.2{\times}10^{11}$ [acrylonitrile butadiene styrene and polycarbonate filaments). For these same machines, total volatile organic compound ERs (${\mu}g/min$) ranged from $1.9{\times}10^4$ (acrylonitrile butadiene styrene and polycarbonate) to $9.4{\times}10^4$ (Ultem). For the material jetting machines, the number-based particle ER was higher when the lid was open ($2.3{\times}10^{10}number/min$) than when the lid was closed ($1.5-5.5{\times}10^9number/min$); total volatile organic compound ERs were similar regardless of the lid position. Low levels of acetone, benzene, toluene, and m,p-xylene were common to both AM processes. Carbonyl compounds were detected; however, none were specifically attributed to the AM processes. Personal exposures to metals (aluminum and iron) and eight volatile organic compounds were all below National Institute for Occupational Safety and Health (NIOSH)-recommended exposure levels. Conclusion: Industrial-scale AM machines using thermoplastics and resins released particles and organic vapors into workplace air. More research is needed to understand factors influencing real-world industrial-scale AM process emissions and exposures.

• Korean Journal of Acupuncture
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• v.40 no.4
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• pp.141-148
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• 2023

Objectives : The purpose of this study is to investigate on the application of the yttrium aluminum garnet (YAG) lasers for acupoints irradiation. Methods : We conducted a systematic search for peer-reviewed studies published from inception to November 2023, in the following electronic databases: PubMed, Scopus, and Web of Science in English, Science ON, Oriental Medicine Advanced Searching Integrated System (OASIS) and Research Information Sharing Service (RISS) in Korean, and China National Knowledge Infrastructure (CNKI) and Wanfang in Chinese, and Japan Science Technology Information Aggregator, Electronic (J-STAGE) and Citation Information by NII (CiNii) in Japanese. Inclusion criteria were original articles including clinical and experimental studies related with YAG lasers for acupoints including Ashi or meridian sinews. Results : Among the 8 selected studies, there were 7 studies on human subjects and 1 study on animals, 7 studies on Nd:YAG (1,064 nm) laser, and 1 study on Er:YAG (2,940 nm) laser. A total of 16 acupoints were used, 15 of which were in the face and 1 of which was located in the foot. In addition, there were two studies using Ashi. 4 studies looked at the effect of pain relief, 2 studies looked at safety, 1 study looked at changes in blood flow, and 1 study looked at the effect of skin care. There were no reported adverse events, and the YAG laser was confirmed to be safe and effective in pain relief, beautifying the skin, and increasing blood flow. Conclusions : We suggest that high intensity YAG lasers can be applied to laser acupuncture or laser moxibustion. YAG lasers are considered to be worth using for various clinical indications of Korean medicine because of photobiomodulation effects, analgesic action, and deep penetration depth. Further scientific research and clinical evidences should be warranted.