• Korean Journal of Materials Research
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• v.21 no.2
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• pp.125-132
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• 2011

Fibrous chitosan membranes were fabricated as a substrate for skin applications using an electro-spinning process with different solvents and varying concentrations. Scanning electron microscopy (SEM) images confirmed that the formation of the chitosan fibrous membrane in trifluoroacetic acid was better than that in acetic acid. Fourier transform infrared spectroscopy showed that the chitosan fibers were cross-linked with glutaraldehyde, and that the cytotoxicity of the aldehyde groups was reduced by glycine and washing by NaOH and DI water. Chitosan cross-linked fibrous membranes were insoluble in water and could be washed thoroughly to wash away glycine and excess NaOH and prevent the infiltration of other water soluble bio-toxic agents using DI water. MTT assay method was employed to test the cytotoxicity of chitosan membranes during fabricating, treating and washing processes. After the dehydration of cell cultured chitosan membranes, cell attachment behavior on the material was evaluated using SEM method. Effect of the treatment processes on the biocompatibility of the chitosan membranes was shown by comparing of filopodium and lamellipodium of fibroblast cells on grown washed and unwashed chitosan fibrous membrane. The MTT assay and SEM morphology confirmed that the washed chitosan fibrous membrane increased cell attachment and cell growth, and decreased toxicity compared to results for the unwashed chitosan fibrous membrane.

• Journal of Korean Society on Water Environment
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• v.33 no.2
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• pp.211-218
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• 2017

This experiment was carried out with the purpose of testing cadmium adsorption abilities of multi wall carbon nanotube (MWCNT), activated carbon, and synthesized layered double hydroxide (LDH). In the acidic condition, only MWCNT was effective for removing cadmium ion in the aqueous phase while other adsorbents rarely removed it. The MWCNT and cadmium ion adsorption reactions followed pseudo-first order kinetic. When the initial pH value was neutral (pH = 7), cadmium ion was rapidly removed by MWCNT and activated carbon in 4 hr (100% and 99.2%, respectively). Increasing adsorbent dosages affects the pH evolution and cadmium ion removal (0 to 99%). Cytotoxicity test showed that both MWCNT and LDH has low cytotoxic effects on three kind of human cells (A549, HS-294t, and HT-29).

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5243-5248
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• 2013

Background: Triptolide, extracted from the herb Tripteryglum wilfordii Hook.f that has long been used as a natural medicine in China, has attracted much interest for its anti-cancer effects against some kinds of tumours in recent years. Artesunate, extracted from the Chinese herb Artemisia annua, has proven to be effective and safe as an anti-malarial drug that possesses anticancer potential. The present study attempted to clarify if triptolide enhances artesunate-induced cytotoxicity in pancreatic cancer cell lines in vitro and in vivo. Methods: In vitro, to test synergic actions, cell viability and apoptosis were analyzed after treatment of pancreatic cancer cell lines with the two agents singly or in combination. The molecular mechanisms of apoptotic effects were also explored using qRT-PCR and Western blotting. In vivo, a tumor xenograft model was established in nude mice, for assessment of inhibitory effects of triptolide and artesunate. Results: We could show that the combination of triptolide and artesunate could inhibit pancreatic cancer cell line growth, and induce apoptosis, accompanied by expression of HSP 20 and HSP 27, indicating important roles in the synergic effects. Moreover, tumor growth was decreased with triptolide and artesunate synergy. Conclusion: Our result indicated that triptolide and artesunate in combination at low concentrations can exert synergistic anti-tumor effects in pancreatic cancer cells with potential clinical applications.

• Journal of Microbiology and Biotechnology
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• v.30 no.5
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• pp.733-738
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• 2020

Glucose deprivation and hypoxia frequently occur in solid tumor cells, including pancreatic cancer cells. Glucose deprivation activates the unfolded protein response (UPR) and causes the up-regulation of glucose-regulated protein 78 (GRP78). Induction of GRP78 has been shown to protect cancer cells. Therefore, shutting down of GRP78 expression may be a novel strategy in anticancer drug development. Based on this understanding, a screening system established for anticancer agents that exhibit selective cytotoxicity on pancreatic cancer cells under glucose-deprived conditions. To test this hypothesis, the new compounds isolated, pancastatin A (PST-A) and B (PST-B), from Ponciri Fructus. PST-A and B were identified as glabretal triterpenoid moieties by electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopic methods. PST-A and B suppressed the accumulation of the UPR hallmark gene, GRP78, during glucose deprivation. Furthermore, PST-A and B showed selective cytotoxicity on PANC-1 pancreatic cancer cells under glucose deprivation. Interestingly, PST-A and B had no effect on these cells under normal growth conditions. Our results suggest that PST-A and B act as novel therapeutic agents to induce selective cell death in glucose-deprived pancreatic cancer cells.

• Archives of Pharmacal Research
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• v.18 no.4
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• pp.256-261
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• 1995

The elevation of intracellular $Ca^{2+}$ in various tissue through oxidative stress induced by menadione has been well documented. Increase of $Ca^{2+}$ level inplatelets results in aggreaction of patelets. To test the hypothesis that menadione-induced $Ca^{2+}$ elevations can play a role in platelet aggregation, we have studied the effect of menadione on aggragation of platelets isolated from female rats. Treatment with menadione to platelet rich plasma (PRP), which proved to be 60% as determined by aggregometry. however, exposure of PRP to menadione leads to a loss of cell viability, as measured by lactae dehydrogenase (LDH) leakage, suggesting that menadione might induce cell lysis rather than aggregation of platelets. Turbidty changes induced by menadione were unaffected by addition ofl dicoumarol, which is a quinone reducellular factions of patelets. These data, which indicate an absence of the QR detoxifying pathway, suggest that platelets may be more susceptible to menadione-induced cytotoxicity than certain other cell, as hepatocytes.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.5
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• pp.751-758
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• 2010

Prunus mume is well known contain many functional materials that play beneficial roles in the human body. Studies have found that many organic acids and polyphenol compounds exist in Prunus mume. In this study, content of total polyphenols and flavonoids, antioxidative activity and cytotoxicity of ethanol extract from Prunus mume were measured Contents of total polyphenolic and total flavonoid compounds in ethanol extract from Prunus mume were 16.92 mg/g and 59.95 mg/g, respectively. The $IC_{50}$ of ethanol extract from Prunus mume were $237.72 {\mu}g$/assay and $239.58 {\mu}g$/assay by DPPH and ABTS radical cation scavenging test, respectively. Additionally, ferric ion reducing antioxidant power (FRAP) value of ethanol extract from Prunus mume was 0.94 mM ($FeSO_4$ eq.) by $800 {\mu}g$/assay. Cytotoxicity of Prunus mume against five kinds of cancer cell lines increased as the extract concentration increased Especially, cytotoxicity of the ethanol extract against A-549 (lung cancer line) was higher than that against any other cancer cell line by both MTT and SRB assay. These results show that ethanol extract of Prunus mume has considerably high antioxidative and cytotoxic activities.

• Biomolecules & Therapeutics
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• v.7 no.1
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• pp.22-28
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• 1999

Induction of apoptosis is considered to be the underlying mechanism that accounts for the efficiency of chemotherapeutic drugs. It has recently been proposed that doxorubicin (DOX) can induce apoptosis in human leukemic cells via the Fas/Fas Ligand (FasL) system. Comparison of Fas and FasL mRNA expression between drug- and anti-Fas antibody(Fas-Ab)- induced apoptosis was analyzed for examining the role of Fas/FasL system in the mediation of drug-induced apoptosis. After HL-60 cells were routinely cultured, MTT assay was performed for cytotoxicity test. Giemsa staining was carried out to monitor the apoptosis morphologically. By semiquantitative RT-PCR analysis, the expression of Fas and FasL at 4, 10, 24 hours was determined after DOX and Fas-Ab treatment. Dose-dependent cytotoxicity was induced by DOX-treatment, while Fas-Ab treatment showed the similar dose-dependent pattern but the cytotoxicity is not reached at LD$_{50}$ at 100 ng/ml concentration of Fas-Ab. In the 10ng/m1 DOX and 10ng/m1 Fas-Ab treated group, typical apoptotic cell morphology was shown such as fragmented nuclei and cell membrane budding in the Giemsa-stained slide. Fas mRNA expression was not changed significantly in the both groups. But, FasL mRNA expression was induced significantly at initial period of apoptosis. In this study, Fas/FasL interaction assumed to be involved in drug-induced apoptosis.s.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.1
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• pp.1-22
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• 1999

In order to investigate various physical and biological properties of dental magnetic attachments studies on retentive characteristics, corrosion properties, cytotoxicity of different magnetic systems for dental applications were done. For the study of retentive characteristics changes of retentive force by increasing air gap, wear properties of various attachment systems and loss of magnetic force by heat treatment were measured. Forte study of corrosion property of magnet covering metal electrochemical corrosion was done in artificial saliva and 0.9% NaCl solution between $-1,000mV_{SCE}\;and\;+1,000mV_{SCE}$. Anodic polarization curves are obtained about 6 types of samples and 2 types of solution. Corroded surfaces were examined with metallurgical microscope, scanning electron microscope and surface profilometer. For the study of cytotoxicity of magnetic attachment and its field cell growth and agar overlay test were done. The results of this study were as follows. 1. In Magnetic attachments using closed circuit retentive force at zero air gap was greater than magnets using open circuit, but decrease of retentive force by increasing air gap was also greater than open systems. 2. After 40,000 cycles of wear test all mechanical attachment resulted in varing degree of retention loss but in magnetic attachments no loss of retentive force was observed. 3. The magnetic attachment using Neodymium magnet showed early loss of retentive force about $200^{\circ}C$ but attachment using Samarium magnet showed some resistance to heat treatment and complete retention loss was observed about $500^{\circ}C$. The keeper was not influenced by heat treatment in retention. 4. In electrochemical corrosion test Dyna magnetic attachment covering metal showed the highiest corrosion resistance and Shiner magnet covering metal showed the least corrosion resistance and examination of corroded surface with metallurgical microscope, scanning electron micro-scope and surface profilometer also showed same results with anodic polarization corves. 5. The result of cell culture tests on the magnet covered with metal showed least recognizable cytotoxicity.

• Archives of Pharmacal Research
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• v.16 no.4
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• pp.259-264
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• 1993

Three cell lines, CHO, L929 and B16 which are non-tumorigenic and cancer cells, respectively, were first tested for their survival in the presence of radioprotective ginseng protein fraction(GPF0. The influence of three radioprotectors-CPF, cysteamine, and 1-Methyl-2-bis[(2-methylthio)vinyl] quinolinium iodide (MVQI) on DNA repair capacity of UV damaged cells survival test, the GPF showed higher cytotoxicity in L929 and B16 than in CHO cells. However, the degree of cell killing was also investigated by measuring $^3H$-thymidine incorporation of PUVA treated cells. In cell survival test, the GPF showed higher cytotoxicity in L929 and B16 than in CHO cells. However, the degree of cell killing was not high enough to consider it as an antitumorigenic agent. Variable results were obtained in the effects on DNA repair capacity depending on the protectors and cell lines used. In pretreatment, the presence of GPF and MVOI brought about a sinificant increase in the capacity in both CHO and B16 cells. However, in L929, the enhancing effect was not shown. In all three cell lines, cysteamine showed lower repair capacity than control, suggesting the primary damage reduction in stronger enhancing effects in L929 and B16 cells, while it was weaker in CHO cells. Here also cystemine hsowed a very little or no increase in the capacity in all three cell lines. These results demonstrate that GPF has mild cytotoxicity in tumorignic cells and that GPF and MVQI enhance DNA repair capacity of UV damaged cells, whether they are tumorigenic or not. On the other hand, cysteamine shows only damage reduction effect. Celles of different genetic origin seem to give different responses to the modifier and different modifiers may possibly work by different mechanisms.

• Journal of the Korea Convergence Society
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• v.12 no.8
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• pp.187-195
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• 2021

In order to assess the cell toxicity of 10 instruments made of polymers, the MTT assay which utilizes the L-929 cell was selected. Specimens were eluted at a temperature of 37℃ for 24 hours at a rate of 4g per 20mL, RPMI 1640, and then was positively and negatively contrasted with a control test solution, in accordance with the Notification No. 2020-12 Protocols of Medical Apparatus Biological Safety from the Ministry of Drug and Food Safety. As a result of 24 hours of incubation in 37℃, 5% CO₂ Incubator and assessment using an ELISA reader, the results of Intraoral camera indiciated a cellular viability of more than 70% at a 50% eluate. But, the Plastic impression tray, 3D printing tweezer, Impression disposable syringe, Dental floss holder, Hand implant scaler, Surgical retractor, Oral scanner tip, Dental mirror, and the Water pick tip all reported a cellular viability of more than 70% at a 100% eluate, which indicates that do not exhibit cytotoxicity, thus allowing it to be used in contact with the mucous membrane of the oral cavity.