1.Effects of dexamethasone and DHEA on the responses of rat cerebral cortical astrocytes to lipopolysaccharide and antimycin A .
Sang Hyun CHOI ; Hyung Gun KIM ; Chang Keun KIM ; Nan Hyang PARK ; Dong Hee CHOI ; In Sop SHIM ; Boe Gwun CHUN
The Korean Journal of Physiology and Pharmacology 1999;3(2):127-135
As part of a study on the effects of dexamethasone and dehydroepiandrosterone (DHEA) on the biological roles of astrocytes in brain injury, this study evaluated the effects of dexamethasone and DHEA on the responses of primary cultured rat cortical astrocytes to lipopolysaccharide (LPS) and antimycin A. Dexamethasone decreased spontaneous release of LDH from astrocytes, and the dexamethasone effect was inhibited by DHEA. However, the inhibitory effect of DHEA on the dexamethasone-induced decrease of LDH release was not shown in astrocytes treated with LPS, and antimycin A-induced LDH release was not affected by dexamethasone or DHEA. Unlike dexamethasone, DHEA increased MTT value of astrocytes and also attenuated the antimycin A-induced decrease of MTT value. Glutamine synthetase activity of astrocytes was not affected by DHEA or LPS but increased by dexamethasone, and the dexamethasone-dependent increase was attenuated by DHEA. However, antimycin A markedly decreased glutamine synthetase activity, and the antimycin A effect was not affected by dexamethasone or DHEA. Basal release of (3H)arachidonic acid from astrocytes was moderately increased by LPS and markedly by antimycin A. Dexamethasone inhibited the basal and LPS-dependent releases of (3H)arachidonic acid, but neither dexamethasone nor DHEA affected antimycin A-induced (3H)arachidonic acid release. Basal IL-6 release from astrocytes was not affected by dexamethasone or DHEA but markedly increased by LPS and antimycin A. LPS-induced IL-6 release was attenuated by dexamethasone but was little affected by DHEA, and antimycin A-induced IL-6 release was attenuated by DHEA as well as dexamethasone. At the concentration of dexamethasone and DHEA which does not affect basal NO release from astrocytes, they moderately inhibited LPS-induced NO release but little affected antimycin A-induced decrease of NO release. Taken together, these results suggest that dexamethasone and DHEA, in somewhat different manners, modulate the astrocyte reactivity in brain injuries inhibitorily.
Animals
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Antimycin A*
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Arachidonic Acid
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Astrocytes*
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Brain Injuries
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Dehydroepiandrosterone*
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Dexamethasone*
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Glutamate-Ammonia Ligase
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Interleukin-6
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Nitric Oxide
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Rats*
2.Comparative Study for the Determination of HER2 gene Amplification and Overexpression in Breast Cancer.
Ho Yong PARK ; Kyu Ha HWANG ; Jin Hyang JUNG ; Jin Young PARK ; Young Ha LEE ; Nan Young LEE ; Jang Soo SUH ; Han Ik BAE ; Youn Kyung SON ; Mun Sup SIM
Journal of the Korean Surgical Society 2005;68(2):83-89
PURPOSE: The human epidermal growth factor receptor-2 (HER2) is overexpressed in breast cancer. The subset of patients with breast cancer demonstrating a HER2-positive status has aggressive tumors and a poor prognosis. Knowledge of the HER2 status is prerequisite when considering a patient's eligibility for anti-HER2 targeted therapy (Herceptin(R)). There are several assays available for determining the HER2 status. The aim of this study was to compare and evaluate the HER2 status in breast cancer by means of immunohistochemistry (IHC), FISH and real-time PCR. METHODS: DNA samples from fresh tumor tissues of 20 patients with breast cancer were analyzed with real-time PCR, using the LightCycler-HER2/neu PCR assay. A tissue microarray, containing 20 samples obtained from formalin- fixed, paraffin-embedded tissues, was used for IHC and FISH (PathyVysionTM). RESULTS: The frequencies of HER2 gene amplification for real-time PCR and FISH were 35 and 65% respectively, and the IHC frequency of overexpression was 70%. This study showed 75% concordance between IHC vs. FISH, 65% between IHC vs real-time PCR and 70% between FISH vs. real-time PCR. Considering real-time PCR as the gold standard, this study showed sensitivities and specificities of 100 and 46.2% for IHC, and of 100% and 53.8% for FISH. CONCLUSION: These results demonstrated marked discordance for the HER2 stati according to the various methods used. IHC, a familiar cost-effective test, will undoubtedly remain in routine clinical practice for HER2 screening but confirmatory HER2 testing using either FISH or real-time PCR is recommended for indeterminate cases. Real-time quantitative PCR for HER2 appears to be clinically useful due to its simplicity and ability to produce rapid results.
Breast Neoplasms*
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Breast*
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DNA
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Epidermal Growth Factor
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Genes, erbB-2*
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Humans
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Immunohistochemistry
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Mass Screening
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Polymerase Chain Reaction
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Prognosis
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Real-Time Polymerase Chain Reaction
3.Preliminary Investigation on Efficacy and Safety of Substance P-Coated Stent for Promoting Re-Endothelialization: A Porcine Coronary Artery Restenosis Model
Dae Sung PARK ; Seok OH ; Yu Jeong JIN ; Mi Hyang NA ; Munki KIM ; Jeong Ha KIM ; Dae Young HYUN ; Kyung Hoon CHO ; Young Joon HONG ; Ju Han KIM ; Youngkeun AHN ; Manuel HERMIDA-PRIETO ; José Manuel VÁZQUEZ-RODRIGUEZ ; Juan Luis GUTIÉRREZ- CHICO ; Luis MARINÃS-PARDO ; Kyung Seob LIM ; Jun-Kyu PARK ; Dae-Heung BYEON ; Young-Nan CHO ; Seung-Jung KEE ; Doo Sun SIM ; Myung Ho JEONG
Tissue Engineering and Regenerative Medicine 2024;21(1):53-64
BACKGROUND:
Current polymer-based drug-eluting stents (DESs) have fundamental issues about inflammation and delayed re-endothelializaton of the vessel wall. Substance-P (SP), which plays an important role in inflammation and endothelial cells, has not yet been applied to coronary stents. Therefore, this study compares poly lactic-co-glycolic acid (PLGA)-based everolimus-eluting stents (PLGA-EESs) versus 2-methacryloyloxyethyl phosphorylcholine (MPC)-based SP-eluting stents (MPC-SPs) in in-vitro and in-vivo models.
METHODS:
The morphology of the stent surface and peptide/drug release kinetics from stents were evaluated. The invitro proliferative effect of SP released from MPC-SP is evaluated using human umbilical vein endothelial cell. Finally, the safety and efficacy of the stent are evaluated after inserting it into a pig’s coronary artery.
RESULTS:
Similar to PLGA-EES, MPC-SP had a uniform surface morphology with very thin coating layer thickness (2.074 lm). MPC-SP showed sustained drug release of SP for over 2 weeks. Endothelial cell proliferation was significantly increased in groups treated with SP (n = 3) compared with the control (n = 3) and those with everolimus (n = 3) (SP:118.9 ± 7.61% vs. everolimus: 64.3 ± 12.37% vs. the control: 100 ± 6.64%, p < 0.05). In the animal study, the percent stenosis was higher in MPC-SP group (n = 7) compared to PLGA-EES group (n = 7) (MPC-SP: 28.6 ± 10.7% vs. PLGAEES: 16.7 ± 6.3%, p < 0.05). MPC-SP group showed, however, lower inflammation (MPC-SP: 0.3 ± 0.26 vs. PLGAEES: 1.2 ± 0.48, p < 0.05) and fibrin deposition (MPC-SP: 1.0 ± 0.73 vs. PLGA-EES: 1.5 ± 0.59, p < 0.05) around the stent strut. MPC-SP showed more increased expression of cluster of differentiation 31, suggesting enhanced reendothelialization.
CONCLUSION
Compared to PLGA-EES, MPC-SP demonstrated more decreased inflammation of the vascular wall and enhanced re-endothelialization and stent coverage. Hence, MPC-SP has the potential therapeutic benefits for the treatment of coronary artery disease by solving limitations of currently available DESs.