• Composites Research
• /
• v.35 no.3
• /
• pp.153-160
• /
• 2022

Cellulose nanofibrils (CNF) based on wood pulp fibers are gained much attention as part of biocompatible hydrogels for biomedical applications such as tissue engineering scaffolds, biomedicine, and drug carrier. However, CNF hydrogels have relatively poor mechanical properties, impeding their applications requiring high mechanical integrity. In this work, we prepare 2,2,6,6-tetramethylipiperidin-oxyl (TEMPO) oxidated cellulose nanofibrils hydrogels mediated with metal cations, which form the metal-carboxylate coordination bonds for enhanced mechanical strength and toughness. We conduct the large amplitude oscillatory shear (LAOS) test and Live/dead cell assay for obtaining nonlinear viscoelastic parameters and cell viability, respectively. In particular, the cell proliferation and viability change depending on the type of metal salt, which also affected the rheological properties of the hydrogels.

• Journal of Aquaculture
• /
• v.22 no.1
• /
• pp.68-73
• /
• 2009

Yeast has been widely used as a food organism for mass culture of rotifer and also considered as a partial substitute food for microalga in shellfish culture. But the dietary value of yeast is poorer than that of microalga due to its low nutrition and thick cell wall. This study was carried out to find a nutritious yeast species as a food organism and to investigate the nutritional value of manipulated yeast for shellfish. First of all, three species of yeast (Saccharomyces cerevisiae, Candida utilis, Kluyveromyces fragilis) and their manipulated yeast were tested on the survival (%) and growth of Artemia nauplii and Mytilus edulis larvae, which were representative filter feeding animal and easy to control. The survival (%) and growth of Artemia nauplii fed C. utilis were higher than those fed S. cerevisiae or K. fragilis. The growth of Artemia nauplii and M. edulis larvae, which were fed manipulated yeast was higher than that fed non-manipulated one. The manipulated yeast with higher removal rate of cell wall showed better dietary value for Artemia nauplii and M. edulis larvae. M. edulis larvae fed mixed-diet with Isochrysis galbana (50%) and manipulated C. utilis (50%) showed significantly higher growth than those fed single-diet with I. galbana. It means that manipulated C. utilis can substitute I. galbana at least 50% for M. edulis larvae.

• Journal of Chest Surgery
• /
• v.29 no.11
• /
• pp.1241-1247
• /
• 1996

From January 1989 to March 1996, we have operated on 102 cases of non-small cell lung cancer at the department of Thoracic and Cardiovascular Surgery, Yonsei University Wonju College of Medicine. They were clinically evaluated. The results are as follows; 1. The peak incidence of age of primary lung cancer was 5th decade(34.3%) and 6th decade(38.2%). Male to female ratio was 2.5:1. 2. Most of symptoms were respiratory, which were cough(61.8%), sputum(43.l%), chest discomfort and pain(30.4%), dyspnea(27.5%), and hemoptysis(9.8%). Asymptomatic cases were 1.9% of study group. 3. Methods of diagnostic confirmation were bronchoscopic biopsy(59.8%), sputum cytology(17.6%), percutaneous needle aspiration(11.8%) and open biopsy(10.8%). 4. Histopathologic classifications were squamous cell carcinoma(55.9%), adenocarcinoma(30.5%), adenosquamous cell carcinoma(6.9%), large cell carcinoma(4.9%), bronchioalveolar cell carcinoma(0.9%), and mixed cell carcinoma(0.9%). 5. Methods of operation were pneumonectony(47.1%), lobectomy(38.2%), bilobectomy(5.9%), wedge resection(1.9%), exploration(6.9%), and overall resectability was 93.1%. 6. Postoperative staging classifications were Stage I (13.7%), Stage II(31.4%), Stage IIIa(38.3%), Stage IIIb(14.7%), and Stage IV(1.9%). 7. The postoperative complications developed in 9.8%, and operative mortality was 1.9 %. 8. One year survival rate was 81.7%, 3 year 49.7% and 5 year 21.8%. According to stage, 5 year survival rate was 39% in stage I, 24.3% in stage II, 23.9% in stage IIIa.

• Korean Journal of Clinical Laboratory Science
• /
• v.52 no.4
• /
• pp.408-416
• /
• 2020

This study examined the neuronal cytotoxicity of aluminum chloride (AlCl3), a dementia inducer, and the protective effects of Aster yomena (Kitam.)(AY) extract on AlCl3-induced cytotoxicity in cultured C6 glioma cells. The antioxidative effects, such as the inhibitory ability of xanthine oxidase (XO) and superoxide anion-radical (SAR) scavenging ability, on cell viability were examined. AlCl3 decreased the cell viability significantly in a dose-dependent manner, and the XTT50 value was 130.0 μM in these cultures. The cytotoxicity of AlCl3 was determined to be mid-toxic according to the Borenfreund and Puerner' toxic criteria. Quercetin (QU), an antioxidant, increased the cell viability reduced by AlCl3-induced cytotoxicity. The protective effect of the AY extract on AlCl3-induced cytotoxicity was analyzed. The AY extract increased the cell viability remarkably compared to the AlCl3-treated group and showed the inhibitory ability of XO and SAR-scavenging ability. The cytotoxicity of AlCl3 was correlated with oxidative stress, and the AY extract effectively prevented AlCl3-induced cytotoxicity through its antioxidative effects. In conclusion, natural resources, such as the AY extract, may be a putative agent for improving the cytotoxicity of heavy metallic compounds correlated with oxidative stress, such as AlCl3, a morbid agent.

• Clinical and Experimental Pediatrics
• /
• v.46 no.7
• /
• pp.702-709
• /
• 2003

Purpose : $IFN{\gamma}$ sentitizes many tumor cells to $TNF{\alpha}$ and FASL-mediated apoptosis by enhancing the expression of TNF or FAS/CD95 receptor and modulating the activation of caspase and Bcl-2 family. It has been reported that $IFN{\gamma}$ and $TNF{\alpha}$ synergistically caused differentiation and growth inhibition of neuroblastoma cells. Even though some neuroblastoma cell express FASR/FASL on the cell surface, they could not induce apoptosis by ligation of the FAS/CD95 receptor. But the treatment of $IFN{\gamma}$ is reported to induce apoptosis in some neuroblastoma cell lines through the CD95/CD95L autocrine circuit. In this study, we examined whether $IFN{\gamma}$ could affect $TNF{\alpha}$ and agonistic FAS/CD95 antibody(CH-11)-induced apoptosis against neuroblastoma cell lines that had shown diverse drug sensitivity and resistance. Methods : CHLA-15, CHLA-90 and LA-N-2 neuroblastoma cells were cultured in IMDM and treated with recombinant $IFN{\gamma}$, $TNF{\alpha}$ and CH-11 antibody. Cell viability was measured by DIMSCAN with a fluorescent calcein-AM. Apoptosis was analyzed through flow cytometry using Annexin V-PE and 7-ADD staining and confirmed by pancaspase and caspase-8 blocking experiments. The expression of TNF RI and FAS/CD95 receptor was evaluated by flow cytometry using the corresponding antibody and PE-conjugated secondary antibody. Results : $IFN{\gamma}$ or $TNF{\alpha}$ alone had no demonstrable cytotoxic effects, whereas both cytokines in combination induced apoptosis synergistically in CHLA-15 and CHLA-90 cells. Although there was no cytotoxicity with the ligation of CH-11 alone in CHLA-90 cells, pretreatment of $IFN{\gamma}$ increased the sensitivity of CH-11-mediated apoptosis. The expression of TNFRI and FAS/CD95R were non-specifically enhanced after treatment of $IFN{\gamma}$ without relation to sensitivity to $TNF{\alpha}$ and CH-11. This finding suggest up-regulation of both receptors may contribute to sensitization of $TNF{\alpha}$ and CH-11-mediated apoptosis by $IFN{\gamma}$ in only sensitive cell lines. Conclusion : $IFN{\gamma}$ induced sensitization of $TNF{\alpha}$ and agonistic FAS/CD95 antibody-mediated apoptosis on some neuroblastoma cells through up-regulation of TNFRI and FAS/CD95 receptor.

• Journal of Korean Ophthalmic Optics Society
• /
• v.18 no.4
• /
• pp.525-531
• /
• 2013

Purpose: To identify the apoptosis caused by Proparacaine hydrochloride (PPC), a topical anesthesia, applied to conjunctival cell lines and determine whether pigallocatechin-gallate (EGCG), has protective effects on. Methods: The conjunctival cell lines were treated with 0.5% of Alcaine$^{(R)}$, 0.5% of PPC and 0.01% of Benzalkonium chloride (BAC) for 15 minutes, respectively in order to investigate the effects of topical anesthesia on cells, and followed by cultured for 12 and 24 hours. The recovery effects were investigated by measuring level of cellular proliferation inhibiting using MTT assay and LDH assay. The conjunctival cell lines were pre-treated with EGCG $10{\mu}M$ for 3 hrs and post-treated with 0.5% PPC for 15 mins in order to investigate whether EGCG has protective effects, flow cytometry were performed in order to observe apoptosis. Results: A result of the additional culture of 12 and 24 hours and again immediately after the treatment for 15 minutes 0.5% of Alcaine$^{(R)}$, 0.5% of PPC, the 0.01% of BAC, cell viability was not increased in all groups (p<0.05). The cell viabilities were higher than in cells 3 hours post-treated with $10{\mu}M$ of EGCG and pre-treated PPC 0.5% (68.2%), compared to cells ($32.2{\pm}2.0%$) treated only with 0.5% of PPC. PPC 0.5% also induced apoptosis in the treated group was reduced by the addition of EGCG. Conclusions: It is considered that the EGCG has cell protective effects when it is added to PPC, a topical anesthesia, by improving cell viability and inhibiting apoptosis.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.7
• /
• pp.801-808
• /
• 2017

The present study investigated the protective effects of Bifidobacterium bifidum culture supernatants (BbSC) and intracellular cell-free extracts (BbICFE) on human dermal fibroblasts (HDFs) against ultraviolet-B (UV-B) irradiation. HDFs were treated with UV-B, UV-B+BbCS, and UV-B+BbICFE. Treatment of UV-B-irradiated HDFs with BbCS and BbICFE significantly increased cell viability compared to UV-B-irradiated HDFs. BbCS treatment reduced senescence in HDFs by approximately 40.0%. Moreover, sub-G1 phase was significantly reduced in BbCS- and BbICFE-treated HDFs (3.3% and 4.5%, respectively). The effect of UV-B on oxidative damage of HDFs was measured by dichlorofluorescin diacetate. Fluorescence intensity significantly increased in UV-B-irradiated HDFs. Inhibition of cellular reactive oxygen species in HDFs treated with 0.01% BbCS was the highest at 34.1%. Levels of p21 and p53 protein expression induced by UV-B irradiation were reduced by treatment with BbCS and BbICFE (47.0% and 35.6%, respectively). These results show that BbCS and BbICFE reduce UV-B-induced cellular senescence and apoptosis in HDFs. Thus, BbCS and BbICFE can be used as potential agents for protection of UV-B-induced skin cell damage.

• Korean Journal of Clinical Laboratory Science
• /
• v.51 no.2
• /
• pp.205-213
• /
• 2019

The protective effect of Agrimonia pilosa var. (AP) extract on potassium dichromate ($K_2Cr_2O_7$)-induced cytotoxicity in cultured NIH3T3 fibroblasts, was examined by performing an XTT assay for the cell viability and antioxidative effects, such as lactate dehydrogenase (LDH) activity and superoxide anion-radical (SAR) scavenging activity. In this study, $K_2Cr_2O_7$ decreased the cell viability significantly in a dose-dependent manner, and the $XTT_{50}$ value was determined to be $37.5{\mu}M$, which was highly-toxic according to the Borenfreund and Puerner' toxic criteria. The antioxidant, butylated hydroxytoluene (BHT), increased remarkably the cell viability damaged by $K_2Cr_2O_7$-induced cytotoxicity in these cultures. With regard to the protective effect of the AP extract on $K_2Cr_2O_7$-induced cytotoxicity, AP extract produced a significant increase in cell viability and antioxidative effects as the inhibitory ability LDH and SAR scavenging ability. These findings suggest that oxidative stress is involved in the cytotoxicity of $K_2Cr_2O_7$, and the AP extract effectively protected the cells from $K_2Cr_2O_7$-induced cytotoxicity by antioxidative effects. These results suggest that natural resources, such as AP extract, may be a putative therapeutic agent for the diminution or treatment of cytotoxicity induced by heavy metallic bases, such as $K_2Cr_2O_7$ correlated with oxidative stress.

• Microbiology and Biotechnology Letters
• /
• v.20 no.3
• /
• pp.243-248
• /
• 1992

In order to examine the viability depending on rehydration process and membrane injury of Nocardia mediterranei upon lyophilization, We labeled $3^H$-thymidine in deoxyribonucleic acid of N. mediterrranei to obtain information on the mechanisms of injury caused by lyophilization. Suspensions of rehydrated cells were incubated with added DNase in a buffer solution. Extracellular radioactivity levels appeared to be high in the rehydrated solutions after lyophilization than freezing-thawing. Thus, the membrane systems were injured by lyophilization, but not ovenvhelmed. These considerations were confirmed by electron microscopy. In effects of rehydration, the cell membrane was seriously damaged by strong atmospheric pressure as soon as the inner ampule was opened, but this was not the case without admitting air under vacuum. N. rnediterranei cells, with no additives, were lyophilized and reconstituted without admitting air, virtually about 84% of the cells were viable.

• Environmental Analysis Health and Toxicology
• /
• v.20 no.1
• /
• pp.23-28
• /
• 2005

PAH 위해성 평가의 생체지표 개발을 위하여, benzo[a]pyrene을 인체 간암 세포주인 HepG2세포에 처리하여 암 억제 단백질인 p53 및 관련 단백질의 발현 양상에 대하여 연구하였다. HepG2 세포의 생존력은 benzo[a]pyrene을 노출시킨 군에서 농도가 증가할수록 감소하였다. p53과 인산화 p53의 발현 양상은 benzo[a]pyrene 농도 의존적으로 증가하는 경향을 보였으며, 반면에 아세틸화 p53은 benzo[a]pyrene의 농도가 증가할수록 감소하는 경향을 나타내었다. 세포 주기 조절에 관련된 p21 단백질은 화학 물질 처리에 의해서 p53과 마찬가지로 증가하였으나, CdK4와 Rb 단백질의 발현에는 변화가 없었다. 상관분석 결과 Benzo[a]pyrene 노출, 세포 생존력, p53, 인산화 p53, p21이 서로 높은 상관성을 보였다. 본 연구의 결과는 p53 단백질의 축적이 benzo[a]pyrene 독성에 있어 매우 중요한 현상이며, 이는 선택적인 지표와 함께 p53 이 benzo[a]pyrene과 같은 PAH 계열의 물질의 위해성 평가를 위한 민감한 생체 지표로써 개발될 수 있음을 시사한다.