• Journal of Chest Surgery
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• v.39 no.9 s.266
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• pp.668-673
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• 2006

Background: Docetaxel has been effectively used as an anti-cancer chemotherapuetic agent for various tumor treatments including lung cancer. However, the cell death induction mechanism(s) involved with docetaxel treatment in lung cancer cells has not been known yet. Material and Method: In the present study, the cellular and biochemical changes of NCI-H1703 cells (non-small cell lung cancer cell line, p53-mutant) after docetaxel treatment have been monitored by flow cytometry, fluorescence microscopy and western blot. Result: Docetaxel treatment significantly resulted in decrease of S phase as well as increase of G2 phase, and consequently evoked an increase of cell death in NCI-H1703 cells. After docetaxel exposure the activations of caspase-3 and caspase-9 were detected. Conclusion: Take together, it is suggested that the docetaxel induces NCI-H1703 cell death by caspase-9 and caspase-3 dependent mitochondrial apoptotic pathway.

• Development and Reproduction
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• v.24 no.2
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• pp.113-123
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• 2020

Metformin has been widely used as an antidiabetic drug, and reported to inhibit cell proliferation in many cancers including non-small cell lung cancer (NSCLC). In NSCLC cells, metformin suppresses PI3K/AKT/mTOR signaling pathway, but effect of metformin on RAS/RAF/MEK/ERK signaling pathway is controversial; several studies showed the inhibition of ERK activity, while others demonstrated the activation of ERK in response to metformin exposure. Metformin-induced activation of ERK is therapeutically important, since metformin could enhance cell proliferation through RAS/RAF/MEK/ERK pathway and lead to impairment of its anticancer activity suppressing PI3K/AKT/mTOR pathway, requiring blockade of both signaling pathways for more efficient antitumor effect. The present study tested the combination therapy of metformin and trametinib by monitoring the alterations of regulatory effector proteins of cell signaling pathways and the effect of the combination on cell viability in NCI-H2087 NSCLC cells with NRAS and BRAF mutations. We show that metformin alone blocks PI3K/AKT/mTOR signaling pathway but induces the activation and phosphorylation of ERK. The combination therapy synergistically decreased cell viability in treatment with low doses of two drugs, while it gave antagonistic effect with high doses. These findings suggest that the efficacy of metformin and trametinib combination therapy may depend on the alteration of ERK activity induced by metformin and specific cellular context of cancer cells.

• Journal of Hydrogen and New Energy
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• v.30 no.5
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• pp.401-410
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• 2019

The operating conditions greatly impact the efficiency and performance of polymer electrolyte membrane (PEM) fuel cell systems and must be properly managed to ensure better performance and efficiency. In particular, small variations in operating conditions interact with each other and affect the performance and efficiency of PEM fuel cell systems. Thus, a systematic study is needed to understand how small changes in operating conditions affect the system performance and efficiency. In this paper, an automotive fuel cell system (including cell stack and balance of plant [BOP]) with a turbo-blower was modeled using MATLAB/Simulink platform and the sensitivity analyses of main operating parameters were performed using the developed system model. Effects of small variations in four main parameters (stack temperature, cathode air stoichiometry, cathode pressure, and cathode relative humidity) on the system efficiency were investigated. The results show that cathode pressure has the greatest potential impact on the sensitivity of fuel cell system efficiency. It is expected that this study can be used as a basic guidance to understand the importance of achieving accurate control of the fuel cell operating conditions for the robust operation of automotive PEM fuel cell systems.

• Tuberculosis and Respiratory Diseases
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• v.39 no.6
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• pp.502-510
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• 1992

Background: Neuron specific enolase (NSE) is a neuronal form of the glycolytic enzyme enolase which was first found in extracts of brain tissue, and later in a variety of APUD cells and neurons of the diffuse endocrine system. SCLC shares many APUD properties with normal neuroendocrine cells. NSE immunostaining and serum NSE measurement may be a useful marker of neuroendocrine differentiation in lung tumors and diagnosis of small cell carcinoma. Methods: NSE immunohistochemical staining was done and at the same time serum NSE levels were measured in 22 small cell lung cancer and 21 non small cell lung cancer which were confirmed histologically. Results: 1) NSE immunoreactivity was detected in 9 of the 18 (50%) small cell lung cancer, in 5 of the 16 non small cell lung cancer. 2) Whereas the mean value in non-small cell lung cancer group was $11.79{\pm}4.47\;ng/ml$, the mean level of serum NSE in small cell lung cancer increased up to $59.3{\pm}77.8\;ng/ml$. In small cell lung cancer patients, mean value of limited disease group was $20.19{\pm}12.91\;ng/ml$, while mean value of extended disease group was $91.9{\pm}94.2\;ng/ml$ showing statistically significant difference. If serum levels above 20 ng/ml were tentatively defined as positive, 16 of 22 (73%) patients with SCLC had positive serum NSE level, but only one patient with NSCLC did. There was no correlation between serum NSE level and immunoreactivity of NSE. Conclusion: These studies indicate that serum NSE measurement may be a useful marker for the diagnosis and disease extent and NSE immunostaining can be used to demonstrate the neuroendocrine components of lung tumor.

• Applied Microscopy
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• v.27 no.2
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• pp.155-163
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• 1997

Ultrastructural and histochemical studies were carried out on the prostate gland of a Korean slug (Incilaria fruhstorferi) with light and electron microscopes. The results are as follows. The endothelial tissue of the prostate gland is constituted with tall and narrow ciliated columnar cells, irregularly shaped cells and gland cells in which are included the elongated oval or ellipsoid nucleus those are surrounded by curved membrane. The endothelial tissue of the prostate gland is composed by type-A, B, C and type-D gland cells, and the glanules of type-A, B, and D gland cells are certified to neutral mucopolysaccharide because are related by PAS-alcian blue (pH 2.5) , but the other hand type-C gland cell is only weakly reacted to PAS, but strongly reacted by Million reaction. The glanules of type-A gland cell are small size (about $0.4{\mu}m$) and are seen high electron density, but the glanules of type-B gland cell are large size (about $0.7{\mu}m$) and glanule density is same type-A glanules. Long ellipsoid type-C gland cell contained round nucleus which is well developed beterochromatin in, and that small oval glanules (size, about $0.9{\mu}m$) of moderate high electron density which are formed a group of large glanule together with $4\sim5ea$, but type-D gland cell possessed round small nucleus are seen high electron dense glanules (size, $0.8{\mu}m$).

• Journal of Embryo Transfer
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• v.9 no.1
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• pp.127-137
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• 1994

This study was carried out to investigate the inhibiting or promoting effect of fetal bovine serum fractionated by the molecular weight and to examine the effect of reconstruction of serum fractions on the development of 1- and 2-cell mouse embryos fertilized in vitro (IVEE) . The serum was separated by ultrafiltration or gel filtration methods and added in m-KRB medium for culture of IVFE. The developemental ability(cavitation and hatching) of embryos following culture of day 4 and 6 was compared among fractions. Small molecular weight fraction( <3 kDa) significantly inhibited the development of 1-and 2-cell IVFE to the blastocyst stages, compared with other fractions. One-cell IVFE were more sensitively damaged than 2-cell embryos by that fraction and arrested mainly at 2~4 cell stages. Moreover, small amount(<3%,v /v) of the inhibiting fraction acted even with protein rich fraction(100~30 kDa) and arrested the embryonic development. On the other hand, 100~30 kDa fraction promoted the embryonic development and no inhibiting effect was observed at the level of 50%(v /v) in culture medium In the experiment of gel filtraton, =30 kDa fraction showed the highest promoting effect on the embryonic development, but <4 kDa fraction inhibited significantly the development. These results suggest that serum contains not only small molecular weight inhibitory component(s) but also promoting one rather than albumin on embryonic development. And serum can be more effectively used in the IVF program after removal of inhibitory component(s) by one of above separation methods.

• Korean Journal of Ichthyology
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• v.12 no.1
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• pp.25-32
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• 2000

The structure of skin was studied in Iksookimia longicorpus based on the micro-anatomical investigation of skin fragments taken from four regions. The epidermis was distinguished by two types of skin glands, a small mucous cell and a large club cell. The mucous cell was acid sulfomucins (some sialomueins) but the club cell did not give any histochemical tests for mucosubstances. The presence of a well defined lymphatic system with small lymphocytes was established in the stratum germinativum layer of the epidermis. A large number of blood capillaries run very close to each other just below the basement membrane, and a definite area giving AB and PAS positive was present between the basement membrane and scale.

• Toxicological Research
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• v.18 no.4
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• pp.411-416
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• 2002

Apoptosis, or programmed cell death, is a genetically regulated pathway that is altered in many cancers. Overexpression of bcl-2 leads to resistance to apoptosis and promotes tumorigenesis. To determine the effect of bcl-2 antisense treatment in human lung cancer cell lines, a 20 mer full phosphorothioate oligonucleotide (ODN) targeted at the coding region of the bcl-2 mRNA was synthesized. Western blot analyses were used to examine bcl-2 protein level in five human non-small cell lung cancer (NSCLC) cell lines (NCI-H226, SK-MES-1 NCI-H358, NCI-H522 and NCI-Hl 299) and four human small cell lung cancer (SCLC) cell lines (NCI-H69, NCI-H4l7, HCC-2108 and SW2). Three out of five NSCLC (NCI-H226, SK-MES-1 and NCI-Hl 299) and all of SCLC cell lines expressed Bcl-2 protein. Treatment of these cell with antisense ODN for 48 hours reduced their viability and Bcl-2 protein level. As a conclusion, bcl-2 antisense treatment appears reduction of the Bcl-2 protein levels and cytotoxic effect including apoptosis in human lung cancer cell lines.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4241-4244
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• 2012

The lung adenocarcinoma is considered more aggressive than other types of non-small cell lung cancer. As metabolites of tryptophan degradation along the kynurenine pathway, including kynurenic acid, have been shown to induce immunosuppression and facilitate escape of tumor cells from immune surveillance, a hypothesis was set up that differences in biological behavior between types of lung cancer may be associated with altered activity of the kynurenine metabolic pathway. The aim of the study was to determine kynurenic acid levels in the serum of patients with bronchial adenocarcinoma for comparison with other types of non-small cell lung cancer. A total of 227 patients with non-small cell lung cancer were enrolled in the study, including 71 with adenocarcinoma and 96 with squamous cell carcinoma. Serum kynurenic acid concentration was determined with use of high performance liquid chromatography and fluorometry. The level of kynurenic acid in the serum of patients with adenocarcinoma was significantly higher than in those with squamous cell lung cancer ($107.1{\pm}62.8$ pmol/ml; 95%CI: 92.4 to 132.3 pmol/ml versus $82.1{\pm}47.6$ pmol/ml; 95%CI: 78.5 to 91.2 pmol/ml, respectively; p = 0.027). Differences between other histological types of lung cancer were insignificant. We conclude that increased activity of kynurenine metabolic pathway manifested by elevated serum kynurenic acid level may be one of the factors associated with clinically distinct biological behavior of adenocarcinoma, in particular high invasiveness and rapid progression.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.388-394
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• 1995

We investigated ultrastuctural change of small intestinal mucosal epithelial cell, columnar cell and mucous cell, of hibernating ground squirrel during activating and hibernating stages. In active columnar cells, many mitochondria and rough endoplasmic reticulum were observed. In hibernating columnar cells, more free nhosome than rough endoplasmic reticulum were observed. In active mucous cells, large and many mucosal granules, mitochondria and rough endoplasmic reticulum were observed. Mucosal granules have been secreted excellently. In hibernating mucous cells, small and little mucosal granules and many free ribosome were observed.