• IMMUNE NETWORK
• /
• v.23 no.5
• /
• pp.36.1-36.16
• /
• 2023

Thymic epithelial cells (TECs) play a critical role in thymic development and thymopoiesis. As individuals age, TECs undergo various changes that impact their functions, leading to a reduction in cell numbers and impaired thymic selection. These age-related alterations have been observed in both mice and humans. However, the precise mechanisms underlying age-related TEC dysfunction remain unclear. Furthermore, there is a lack of a comprehensive study that connects mouse and human biological processes in this area. To address this gap, we conducted an extensive transcriptome analysis of young and old TECs in mice, complemented by further analysis of publicly available human TEC single-cell RNA sequencing data. Our analysis revealed alterations in both known and unknown pathways that potentially contribute to age-related TEC dysfunction. Specifically, we observed downregulation of pathways related to cell proliferation, T cell development, metabolism, and cytokine signaling in old age TECs. Conversely, TGF-β, BMP, and Wnt signaling pathways were upregulated, which have been known to be associated with age-related TEC dysfunctions or newly discovered in this study. Importantly, we found that these age-related changes in mouse TECs were consistently present in human TECs as well. This cross-species validation further strengthens the significance of our findings. In conclusion, our comprehensive analysis provides valuable insight into the biological and immunological characteristics of aged TECs in both mice and humans. These findings contribute to a better understanding of thymic involution and age-induced immune dysfunction.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1316-1317
• /
• 2011

This paper presents analysis of temperature and light intensity characteristics of PV modules with solar cell type. Taking the effect of sunlight irradiance on the cell temperature, the first experiment takes ambient temperature as reference input and uses the solar insolation as a unique varying parameter. Then taking the effect of the cell temperature on sunlight irradiance, the second experiment takes 1000W/$m^2$ as reference input and uses the cell temperature as a unique varying parameter. As a result, varying sunlight irradiance, the Cell-Type with the smallest change in output is HIT and the Cell-Type with the biggest change in output is a-Si. Varying the cell temperature, the Cell-Type with the smallest change in output is a-Si and the Cell-Type with the biggest change in output is Single-Si. And considering both temperature and light intensity characteristics, the Cell-Type with the smallest change in output is HIT.

• Microbiology and Biotechnology Letters
• /
• v.20 no.4
• /
• pp.470-476
• /
• 1992

Upon lyophilization of Nocardia mediterranei, the effects of cryoprotectants, cell concentration and drying time on viability were examined, The data were treated by computer according to response surface analysis. As a result, the maximum value of presumed viability was 39.3% under the optimal conditions of 1l.6%(v/v) sucrose, $1.16{\times}10^{11}$(CFU/ml) cell concentration, and drying time for 6.18 hrs. We also used the starter cell of rehydrated solution after lyophilization in industrial production, obtained the fermentation pattern and the purity of rifamycin B which were the same with control (FVM) and it is possible for us to use N mediterranei as a starter cell after the storage of lyophilization for 18 months.

• The Journal of Korean Medicine
• /
• v.30 no.6
• /
• pp.17-26
• /
• 2009

Objectives: Little information is available regarding the effect of Lycii cortex radicis (LCR) on cell viability in glioma cells. This study was therefore undertaken to examine the effect of LCR on cell survival in U87MG human glioma cells. Methods: Cell viability and cell death were estimated by MTT assay and trypan blue exclusion assay, respectively. Reactive oxygen species (ROS) generation was measured using the fluorescence probe DCFH-DA. Activation of Akt and extracellular signal-regulated kinase (ERK) and activation of caspase-3 were estimated by Western blot analysis. Results: LCR resulted in apoptotic cell death in a dose- and time-dependent manner. LCR increased reactive oxygen species (ROS) generation and LCR-induced cell death was also prevented by antioxidants, suggesting that ROS generation played a critical role in LCR-induced cell death. Western blot analysis showed that LCR treatment caused down-regulation of Akt and ERK. The LCR-induced cell death was increased by the inhibitors of Akt and ERK. Activation of caspase-3 was stimulated by LCR and caspase inhibitors prevented the LCR-induced cell death. Conclusion: These findings suggest that LCR results in human glioma cell death through a mechanism involving ROS generation, down-regulation of Akt and ERK, and caspase activation.

• KSBB Journal
• /
• v.9 no.2
• /
• pp.230-237
• /
• 1994

Spin-filters are used as cell separation devices for achieving high cell density and high productivity in animal cell culture. We have proposed a model for the cell growth in a spin-filter perfusion culture and examined the effects on cell growth by several parameters including ammonia inhibition, specific growth rate, specific feeding rate, and cell retention. Results from computer simulation and sensitivity analysis indicate that the cell retention affects the cell growth mostly while there is a significant inhibition on cell growth by the ammonia accumulated during the culture. The specific feeding rate has minimal effects on cell growth, which is consistant with the fact that the cell growth with a step feeding is quite similar to that with a continuous feeding.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.30 no.4
• /
• pp.271-281
• /
• 2004

Adenoid cystic carcinoma is malignant tumor in salivary gland, and its behavior is very invasive. Of all malignant tumor adenoid cystic carcinoma is occured in frequency of 4.4% in major salivary gland, and 1.29% in minor salivary gland. Histopathologically, adenoid cystic carcinoma is characterized by a cribriform appearance, and tubular form and solid nest type tumor can be seen. The tumor cell structure composed of modified myoepithelial cell, and basaloid cell. Extracellular matrix of this tumor cell contains variable ground substance with basement membrane component. Basement membrane matrix composed of collagen fibers, glycoproteins, proteoglycans, and its function is well known that it participate in differentiation, proliferation, and growth of tumor cell. Basement membrane molecule is essential for invasion of peripheral nerve, blood vessel, skeletal muscle in tumor cell of adenoid cystic carcinoma. In many studies, the tumor cell of adenoid cystic carcinoma containing modified myoepithelial cell participate in synthesis of proteoglycan. In this study, tissue sample of adenoid cystic carcinoma of human salivary gland were obtained from 15 surgical specimen, and all specimen were routinely fixed in 10% formalin and embedded. Serial $4-{\mu}m$ thick sections were cut from paraffin blocks. the histopathologic evaluation was done with light microscopy. And, the immunohistochemical staining, characteristics of glycosaminoglycan were observed. For biochemical analysis of glycosaminoglycan, isolation of crude glycosaminoglycan from tumor tissue and Western bolt analysis were carried out. With transmission electomicroscopy, tumor cell were observed. Biologic behavior of adenoid cystic carcinoma was observed with distribution and expression of basement membrane of glycosaminoglycan in tumor cells, The results obtained were as follows: 1. In immunohistochemical study, chondroitin sulfate is postively stained in tumor cell and interstitial space, dermatan sulfate is weakly stained in ductal cell. But keratan sulfate is negatively stained. 2. In immunohistochemical study, heparan sulfate is strong positive stained in tumor cell and basement membrane, especially in invasion area to peripheral nerve tissue. 3. In transmission electromicroscpic view, the tumor cells are composed modifed myoepithelial cells, and contains many microvilli and rough endoplasmic reticulum. 4. In Western blot analysis, the expression of glycosaminoglycan is expressed mostly in heparan sulfate. From the results obtained in this study, tumor cell of adenoid cystic carcinoma is composed modified myoepithelial cell, and glycosaminoglycan of basement membrane molecule of heparan sulfate and chondroitin sulfate mostly participate in the development and invasiveness of adenoid cystic carcinoma by immunohistochemical study and western blot analysis.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.13 no.1
• /
• pp.81-87
• /
• 2004

A 3-D FEM (Finite Element Method) analysis of the turbo-blower shaft attached to a fuel cell was performed using Lanczos algorithm. The modal analysis was analyzed in order to investigate natural frequency and maximum displacement for 10 times. It was found that the first mode of natural frequency is 109.1Hz with the maximum displacement of 0.16mm while the tenth mode of natural frequency is 2464Hz with the maximum displacement of 0.25mm. Consequently, the results of modal analysis of the turbo-blower for a fuel cell system show good dynamic responses.

• Journal of Pharmacopuncture
• /
• v.25 no.4
• /
• pp.390-395
• /
• 2022

Objectives: Sweet bee venom (sBV) is purified from Apis mellifera, containing a high level of melittin-its main component. It has been used as a therapeutic agent for pain relief and anti-inflammation, as well as for treating neuronal abnormalities. Recently, there have been studies on the therapeutic application of sBV for anticancer treatment. In the present study, we investigated the pharmacological effect of sBV treatment in A549 human lung cancer cells. Methods: We used microscopic analysis to observe the morphological changes in A549 cells after sBV treatment. The MTT assay was used to examine the cytotoxic effect after dose-dependent sBV treatment. Molecular changes in sBV were evaluated by the expression of apoptosis marker proteins using western blot analysis. Results: Microscopic analysis suggested that the growth inhibitory effect occurred in a dose-dependent manner; however, cell lysis occurred at a concentration over 20 ㎍/mL of sBV. The MTT assay indicated that sBV treatment exhibited a growth inhibitory effect at a concentration over 5 ㎍/mL. On fluorescence activated cell sorting analysis, G0 dead cells were observed after G1 arrest at treatment concentrations up to 10 ㎍/mL. However, rapid cell rupture was observed at a concentration of 20 ㎍/mL. Western blot analysis demonstrated that sBV treatment modulated the expression of multiple cell death-related proteins, including cleaved-PARP, cleaved-caspase 9, p53, Bcl2, and Bax. Conclusion: sBV induced cell death in A549 human lung cancer cells at a pharmacological concentration, albeit causing hemolytic cell death at a high concentration.

• Journal of Acupuncture Research
• /
• v.32 no.1
• /
• pp.79-88
• /
• 2015

Objectives : The purpose of this research was to investigate the cytotoxic effect of Natural Killer(NK)-92 cell and Snake Venom, and to elucidate its mechanism on human lung carcinoma cell A549. Methods : In order to figure out whether Snake Venom enhances the cytotoxic effect of NK-92 cell in A549 cell, Cell Viability Assay was conducted. Also, in order to observe the changes of Caspase-3 and Caspase-8, both of which are proteinases that advance apoptosis, and the changes of TNRF and DR3, which are Death Receptors of the extrinsic pathway of apoptosis, Western Blot Analysis was conducted. By conducting RT-PCR analysis, we have tried to confirm Perforin, Granzyme B, and GADPH, all of which are cytotoxic-related proteins. Lastly, in order to observe the effect of Snake Venom on NO formation within human lung carcinoma cells, NO determination was conducted. Results : 1. After conducting Cell Viability Assay, Snake Venom enhanced the cytotoxic effect of NK-92 cell and inhibited the growth of A549. 2. Western Blot Analysis caused proteinases Caspase-3 and Caspase-8, which advance apoptosis, to increase in the combined treatment group, but not in treatment groups that focused only on either Snake Venom or NK-92 cell in A549 lung carcinoma cells. 3. Western Blot Analysis caused an expression of TNFR2 and DR3, both of which are Death Receptors of the apoptosis extrinsic pathway, in the combined treatment group, but not intreatment groups that focused only on either Snake Venom or NK-92 cell in A549 human lung carcinoma cells. 4. After conducting NO determination, NO formation within A549 cell showed no significant changes in both treatment groups that focused NK-92 cell and combined treatment group. 5. After conducting RT-PCR, the expression of Granzyme B and Perforin, which are cytotoxic-related proteins within A549 human lung carcinoma cells, showed growth in the combined treatment group, but not the treatment group that focused only on NK-92 cell. Conclusion : It has been indicated that, when it comes to the A549 cell, Snake Venom enhances the increase of Death Receptor expression and continuous apoptosis reaction, leading to the enhancement of the cancer cell cytotoxic effect of the NK-92 cell. It is expected that Snake Venom can be used with the NK-92 cell for further lung cancer treatment.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.5
• /
• pp.1993-1995
• /
• 2015

Purpose: This analysis was conducted to evaluate the efficacy and safety of irinotecan based regimens as second-line chemotherapy in treating patients with small cell lung cancer. Methods: Clinical studies evaluating the efficacy and safety of irinotecan based regimens as second-line chemotherapy for patients with small cell lung cancer were identified using a predefined search strategy. Pooled response rates (RRs) of treatment were calculated. Results: In irinotecan based regimens as second-line chemotherapy, 4 clinical studies which including 155 patients with small cell lung cancer were considered eligible for inclusion. In all chemotherapy consisted of irinotecan with or without nedaplatin. Pooled analysis suggested that, in all patients, the pooled RR was 27.1% (42/155) in irinotecan based regimens. Nausea, vomiting, diarrhea and myelosuppression were the main side effects. No grade III or IV renal or liver toxicity was observed. No treatment related death occurred with the irinotecan based treatments. Conclusion: This systemic analysis suggests that irinotecan based regimens as second-line chemotherapy are associated with mild response rate and acceptable toxicity for patients with small cell lung cancer.