• 대한핵의학회지
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• 제39권2호
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• pp.133-140
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• 2005

The potential for recovery of left ventricular dysfunction after myocardial revascularization represents a practical clinical definition for myocardial viability. The evaluation of viable myocardium in patients with severe global left ventricular dysfunction due to coronary artery disease and with regional dysfunction after acute myocardial infarction is an important issue whether left ventricular dysfunction may be reversible or irreversible after therapy. If the dysfunction is due to stunning or hibernation, functional improvement is observed. but stunned myocardium may recover of dysfunction with no revascularization. Hibernation is chronic process due to chronic reduction in the resting myocardial blood flow. There are two types of myocardial hibernation: "functional hibernation" with preserved contractile reserve and "structural hibernation" without contractile reserve in segments with preserved glucose metabolism. This review focus on the application of F-18 FDG and other radionuclides to evaluate myocardial viability. In addition the factors influencing predictive value of FDG imaging for evaluating viability and the different criteria for viability are also reviewed.

• Asian-Australasian Journal of Animal Sciences
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• 제21권4호
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• pp.494-498
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• 2008

MTT (3-(4, 5-dimethyl thiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) reduction assay is a method that validates the viability of an active cell. Dehydrogenase in mitochondria converts yellow colored insoluble tetrazolium salt to purple colored water-soluble formazan. Sperm also have mitochondria in the midpiece, therefore sperm viability could be evaluated by MTT reduction assay. Several studies have already demonstrated the capability of application of the MTT reduction assay to sperm of several species in Hepes-BSA buffer. Because most liquid semen was diluted in extender like BTS (Beltsville Thawing Solution), Modena or Androhep when it is used or transferred, semen needed another dilution in Hepes-BSA buffer to assess sperm viability. In this study, we evaluated boar sperm viability especially in BTS extended semen and compared the efficiency of this test with eosin-nigrosin staining. We used the fresh BTS extended semen from a local A.I center. Semen sample was diluted to $3.0{\times}10^7$ sperms/ml in BTS. The rates of formazan production were measured in 96-well microtiter plates immediately and 1h after incubation at $17^{\circ}C$ using a spectrophotometer at wave length 560 nm. Simultaneously, split samples of the same semen were tested, using eosin-nigrosin staining to compare the efficiency of the MTT assay of sperm viability in BTS. The correlation between the results of these tests was calculated using Student-t test and ANOVA. The results revealed a strong correlation between the results of MTT reduction rate and the results that were simultaneously determined by eosin-nigrosin staining at 1 h. In conclusion, the MTT reduction test was an effective and simple method to validate sperm viability and it could be used as a simple tool to evaluate sperm viability in the local A.I center and laboratory.

• Biomaterials and Biomechanics in Bioengineering
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• 제3권2호
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• pp.105-114
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• 2016

The purpose of this study is to evaluate the effects of cryopreservation on dental pulp-derived stem cells (DPSC) viability over a period of three years. Dental pulp-derived stem cells were isolated and cultured from thirty-one healthy teeth. DPSC isolates were assessed for doubling-time and baseline viability prior to cryopreservation and were assessed again at three time points; one week (T1), 18 months (T2), and 36 months (T3). DPSC can be grouped based on their observed doubling times; slow (sDT), intermediate (iDT), and rapid (rDT). Viability results demonstrated all three types of DPSC isolates (sDT, iDT and rDT) exhibit time-dependent reductions in viability following cryopreservation, with the greatest reduction observed among sDT-DPSCs and the smallest observed among the rDT-DPSC isolates. Cryopreserved DPSCs demonstrate time-dependent reductions in cellular viability. Although reductions in viability were smallest at the initial time point (T1) and greatest at the final time point (T3), these changes were markedly different among DPSC isolates with similar doubling times (DTs). Furthermore, the analysis of various DPSC biomarkers - including both intracellular and cell surface markers, revealed differential mRNA expression. More specifically, the relative high expression of Sox-2 was only found only among the rDT isolates, which was associated with the smallest reduction in viability over time. The expression of Oct4 and NANOG were also higher among rDT isolates, however, expression was comparatively lower among the sDT isolates that had the highest reduction in cellular viability over the course of this study. These data may suggest that some biomarkers, including Sox-2, Oct4 and NANOG may have some potential for use as biomarkers that may be associated with either higher or lower cellular viability over long-term storage applications although more research will be needed to confirm these findings.

• Journal of Chest Surgery
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• 제28권8호
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• pp.731-741
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• 1995

Cardiac valve allografts have been used as replacements for diseased valves and right ventricular outflow tract reconstruction, the long term follow-up of which has been reported satisfactory. For a good long-term result, it is essential that the allograft be viable at implantation. In this study, we aimed at preparing the cardiac valve allografts aseptically, preserving them at cold- and cryo-conditions, and testing the viability of the allografts after preservation by four methods. We tested the viability of the cardiac valve allografts preserved in cold refrigerated state[4$^{\circ}$C in nutrient media & in liquid nitrogen tank[cryopreservation under -149$^{\circ}$C for pre-planned time periods. The testing methods were 1 glucose utility test 2 tissue culture 3 thymidine uptake test and 4 histologic evidence by light microscopy. We observed no differences in the viability between cold- & cryo-groups and similar results among the methods for testing the viability. In conclusion, there was no difference in the viability between cold- and cryopreserved-allografts at least for 14 days of preservation. And glucose utility test and thymidine uptake test were satisfactory in the evaluation of the allograft viability, since they were easy and rapid with relatively quantitative results.

• Journal of Chest Surgery
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• 제27권1호
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• pp.1-8
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• 1994

Allograft cardiac valves have been used for over 30 years to replace diseased cardiac valves, reconstruct right or left ventricular outflow tract. With increasing its requirement, the establishment of a viable bank capable of maintaining the viability of graft over a prolonged period would be desirable. The method for determining the viability of allograft by metabolic assay technique using radiolabeled aminoacids has been used recently. An experimental study was done for evaluation of viability of cardiac allograft which was preserved for 14 days at 4oC in nutrient medium[fresh preservation] by metabolism assay technique using 3H-glycine. Also, the effectiveness of low concentration antibiotic solution[CLPV] for sterilization was evaluated. The effectiveness of CLPV solution for sterilization of allograft was perfect. Pre-treatment cultured organisms were not cultured after treatment at all in every cases. The viability of allograft after sterilization was reduced to 66.4%[aortic wall], 74.7%[pulmonary wall], 76.3%[aortic valve], 67.9%[aortic wall]. And after the fresh preservation for 14 days, the viability was reduced to 14.7%, 18.5%, 17.7%, 19.0%, respectively.In conclusion, viability of allograft was reduce to 71.3[66.4-76.3]% after sterilization and 17.5[14.7-19.0]% after fresh preservation. And sterilization effect of CLPV solution was satisfactory.

• Fisheries and Aquatic Sciences
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• 제8권4호
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• pp.243-246
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• 2005

The addition of seaweed extracts was found to regulate the viability of cultures of the crustose coralline alga Lithophyllum yessoense. The viability was quantitated using a triphenyltetrazolium chloride assay, and the methanol-soluble extracts from 18 prevalent seaweed species were tested. Extracts from Codium fragile and Enteromorpha linza inhibited viability, and a Hizikia fusiform is extract slightly increased viability. The methanol extract of C. fragile, which had the strongest inhibitory activity, decreased viability to 72 or $52\%$ that of the control following addition of 0.2 or 2 mg/mL of extract to the culture, respectively. The main active compound in the C. fragile was lipid. This information is a preliminary result related to the exploration of seaweed restoration in the algal whitening area.

• Preventive Nutrition and Food Science
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• 제19권4호
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• pp.363-366
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• 2014

Zinc is considered to be involved in maintaining healthy vascular condition. Atherosclerotic calcification of vascular smooth muscle cells (VSMCs) occurs via the mechanism of cell death; therefore, cell viability is a critical factor for preventing VSMC calcification. In this study, we tested whether zinc affected VSMC viability under both normal physiological non-calcifying (0 mM P) and atherosclerotic calcifying conditions (3 and 5 mM P), since VSMC physiological characters change during the VSMC calcification process. The study results showed that an optimal zinc level ($15{\mu}M$) restored the decreased VSMC viability which was induced under low zinc levels (0 and $1{\mu}M$) and calcifying conditions (3 and 5 mM P) at 9 and 15 days culture. This zinc-protecting effect for VSMC viability is more prominent under atherosclerotic calcifying condition (3 and 5 mM P) than normal condition (0 mM P). Also, the increased VSMC viability was consistent with the decreased Ca and P accumulation in VSMC cell layers. The results suggested that zinc could be an effective biomineral for preventing VSMC calcification under atherosclerotic calcifying conditions.

• The Journal of Asian Finance, Economics and Business
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• 제6권1호
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• pp.217-229
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• 2019

The purpose of the research is to verify how task characteristics for business and technology characteristics, economic feasibility, technology readiness, organizational factors, environmental factors of cloud computing affect the performance of cloud computing adoption through Fit and Viability. The research aims to verify the relationship among the success factors for adopting cloud computing based on the Fit-Viability model. Respondents who work for IT companies which is using cloud computing in South Korea were chosen. The data was analyzed by the structural equating model. As a result, Task characteristics and Technology characteristics affected Fit in a positive manner, while Technology readiness, Organizational factors and Environmental factors also positively impacted Viability. Fit and Viability both affected the successful adoption of cloud equally. In particular, Environmental factors were proven to have the biggest impacts on Viability, and affected highly indirect impact on the Performance of cloud computing adoption through Viability. Entering the era of the fourth industrial revolution, corporations have established digital transformation strategies to secure a competitive edge while growing continuously, and are also carrying out various digital transformation initiatives. For the success of adoption of foundational technologies, they need to understand not only the decision-making factors of adopting cloud computing, but also the success factors of adopting cloud computing.

• Journal of Chest Surgery
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• 제30권6호
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• pp.553-558
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• 1997

동종동맥판은 심장판막질환, 선천성 심기형 및 대동맥 질환의 치료에 있어서 우수한 판막도관으로 사용 되고 있다. 이 때 동종동맥 판의 장기성적을 좌우하는데 있어서 혈관내피세포의 생육성이 중요한 역활을 할 것이다. 혈관내피세포의 생육성을 평가하기 위하여 현재 임상에서 사용되는 보존방법으로 보존처리된 성돈의 대동맥판 및 대동맥 벽을 collagenase로 분해시켜서 순수한 내퍼세포군을 획득한 뒤, 혈관내피세포에 특이한 친화성을 갖는 GSA-FTTC(Criffonia simplicifolia agglutininfluorescein isothiocyanate)와 반응시켰다. 이 내피세포군을 세척한 다음, 살아있는 세포에는 침착되지 않는 Pl(Ropidium iodide)와 반응시켰다. 이렇게 처리된 내피세포군을 Row Cytometry 로 분석하여 GSA-FTIC(+), Pl(-) 인 세포를 생육성을 유지한 것으로 평가하였다. 동종동맥판은 $4^{\circ}C의$ 멸균용액에 24시간 담궈 멸균처리를 한 후, 2개군으로 나누어 (1군)은 $4^{\circ}C$ RPM 1640 with HEPES buffer cultlue medium with 10% fetal bovine uTm 용액에 1~14일간 보존하였고 (2군)은 냉동보존을 하였다. 조직의 획득과정과 멸균과정에서 각각 22.8%와 24.4%의 생육성이 소\ulcorner되었다. (1군) 에서는 14일의 보존기간 동안 11.9%의 생육성감소가 일어났고 (2군) 에서는 13.7%의 생육성감소가 일어났다. 이 실험의 결과로 동종동맥 판의 보존처리과정 초기에 대부분의 생육성소실이 일어나며, 14일간의 냉장보존이나 냉동보존 후에도 약 40%의 생육성이 보존됨을 알 수 있었다. 또한 혈관내피세포가 판막에서 얻어진 경우나 동맥벽에서 얻어진 경우에서 생육성의 차이는 없었다.

• 치과방사선
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• 제29권2호
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• pp.435-449
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• 1999

Purpose : The study was aimed to detect the differences in the cell viability and the apoptosis induction after irradiation on normal and tumorigenic cells. Materials and Methods : The study. that was generated for two human normal cells(RHEK, HGF-l) and two human tumor cells(KB. HT-1080). was tested using MTT assay at 1 day and 3 day after irradiation and TUNEL assay under confocal laser scanning microscope at 1 day after irradiation. Single irradiation of 0.5. 1, 2. 4. and 8Gy were applied to the cells. The two fractions of 1. 2. 4. and 8Gy were separated with a 4-hour time interval. The irradiation was done with 5.38Gy/min dose rate using Cs-137 irradiator at room temperature. Results and Conclusions : 1. In 3-day group. the cell viability of HGF-1 cell was significantly decreased at 2. 4 and 8Gy irradiation, the cell viability of KB cell was significantly decreased at 8Gy irradiation and the cell viability of HT-I080 cell was significantly decreased at 4 and 8Gy irradiation. 2. There was significant difference between RHEK and KB cell line in the cell viability of 3-day group at 8Gy irradiation. There was significant difference between RHEK and HGF-1 cell line in the cell viability of 3-day group at 4 and 8Gy irradiation. 3. There was a significantly decreased cell viability in 3-day group than those in 1-day group at 2. 4 and 8Gy on HGF-1 cell. at 4 and 8Gy on HT-I080 cell. at 8Gy on KB cell. 4. We could detect DNA fragmented cells only on KB cell. Number of apoptotic cells of KB cell was significantly increased at 4 and 8Gy irradiation. However, there was no correlation between cell viability and apoptosis. 5. On all 4 cell lines, there were no differences between single and split irradiation method in cell viability and apoptosis.