• The Korean Journal of Physiology and Pharmacology
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• 제9권6호
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• pp.363-369
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• 2005

It is imperative to analyse brain injuries directly in real time, so as to find effective therapeutic compounds to protect brain injuries by stress. We established a system which could elucidate the real time $Ca^{2+}$ dynamics in an organotypic cultured hippocampal slice by the insults of artificial stress hormone, dexamethasone. The real time $Ca^{2+}$ dynamics could continuously be detected in cornus ammonis 3 (CA3) of the organotypic hippocampus for 8 hours under confocal microscopy. When dexamethasone concentration was increased, the $Ca^{2+}$ was also increased in a dose dependent manner at $1{\sim}100{\mu}M$ concentrations. Moreover, when the organotypic cultured hippocampal slice was treated with a glutamate receptor antagonist together with dexamethasone, the real time $Ca^{2+}$ dynamics were decreased. Furthermore, we confirmed by PI uptake study that glutamate receptor antagonist reduced the hippocampal tissue damage caused by dexamethasone treatment. Therefore, our new calcium ion dynamics system in organotypic cultured hippocampal slice after dexamethasone treatment could provide real time analysis method for investigation of brain injuries by stress.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.137-142
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• 2000

Environmental stres is known to induce heat shock proteins (HSPs) in eukaryotic cells. However, the induction of HSPs in host cells by microbial infection has not yet been well explained. Staphylococcus aureus (S. aureus) is one of the major pathogens in the pathogenesis of endovascular diseases such as infective endocarditis. In this study, the synthesis of stress-inducible 70 kDa HSP was investigated in the endothelial cells (ECs) after 3 h to 20 h of incubation with S. aureus. The dffect of S. aureus infection on the expression of HSP70 in cultured ECs was analyzed using laser scanning confocal microscopy (LSCM). The increase of HSP70 expression in ECs infected by S. aureus ($10^4{\;}cfu/ml$) for 20 h was 1.1-fold higher than that in heat shock treated ECs and 2.2-fold higher than that in untreated cells. Heat shock is known to induce intranucleus HSP70 expression in mammalian cells, whereas the S. aureus infection induced perinuclear expression in ECs as observed by LSCM. Consequently, the expression of HSP70 in ECs plays an important role in the pathogenesis of endovascular infection.

• Journal of Microbiology and Biotechnology
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• 제21권10호
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• pp.1026-1035
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• 2011

Vibrio parahaemolyticus, which owes its origin to the marine environment, is considered as one of the most common causes of infectious diarrhea worldwide. The present study investigated the pathogenicity of V. parahaemolyticus against the model organism, Caenorhabditis elegans. Infection in the host was localized with GFP-tagged V. parahaemolyticus using confocal laser scanning microscopy. The times required for causing infection, bacterial load in intestine, chemotactic response, and alteration in pharyngeal pumping were analyzed in the host system. In addition, the regulation of innate immune-related genes, lys-7, clec- 60, and clec-87, was analyzed using real-time PCR. The role of immune-responsible pmk-1 was studied using mutant strains. The pathogenicity of environmental strain CM2 isolated from the Gulf of Mannar, India was compared with that of a reference strain obtained from ATCC. The pathogen infected animals appeared to ward off infection by up-regulating candidate antimicrobial genes for a few hours after the exposure, before succumbing to the pathogen. For the first time, the pathogenicity of V. parahaemolyticus at both the physiological and molecular levels has been studied in detail using the model organism C. elegans.

• 약학회지
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• 제50권2호
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• pp.93-98
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• 2006

Human foamy virus (HFV) integrase mediates integration of viral c-DNA into cellular DNA. In this process, HFV prointegration complex (PIC) in which integrase is a key component moves to nuclei of the infected cells and leads to integration of viral DNA to the cellular genome, which is essential in viral life cycle. In general nuclear localization signals (NLS) have been suggested to be involved in localizing retroviral PIC to nuclei, but the mechanisms for nuclear localization of the HFV PIC remains unclear. To functionally identify the NLS of HFV integrase, various subdomains of the protein were expressed as GFP fusions and their subcellular locations were analyzed with confocal laser scanning microscopy. Wild type HFV integrase was karyophilic by targeting the fusion protein to nuclei of the COS-1 and 293T cells. Our results showed that strong NLS of HFV integrase was mapped to the C-terminal regions. In addition the karyophilic properties of N-terminal and central regions are not individually strong enough to direct localization of the fusion proteins to nuclei, but their cooperative activity for nuclear import was confirmed.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.51.1-51.1
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• 2011

An electrospun Poly (lactice-co-glycolide acid) (PLGA) and Gelatin nanofiber tube was fabricated for potential intestinal stent application. Mechanical properties of tube were evaluated by tensile strength and burst strength tests. Physical and chemical properties were evaluated by contact angle measurement, swelling rates and porosity measurements. Biodegradability was investigated by immersion in simulated body fluid (SBF). Biocompatibility was investigated in vitro by cytotoxicity and proliferation studies by MTT assay, confocal microscopy and western blot using IEC-18 (Rat intestinal epithelial cell). After intestinal stent was implanted into rat bowel for periods from 7 to 10days, it was then analyzed using micro-computed tomography (Micro CT) and X-ray techniques. Futhermore, histological analysis was performed by hematoxylin-eosin (H&E) stain.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.51.2-51.2
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• 2011

A novel electrospun nanofiber membrane was fabricated using combined poly (vinylphosphonic acid) (PVPA) and polyvinyl alcohol (PVA) intended for bone tissue engineering applications. PVPA is a proton-conducting polymer used as primer for bone implants and dental cements to prevent corrosion and brush abrasion. The phosphonate groups of PVPA have the ability to crosslink and attach itself to the hydroxyapatite surface facilitating faster integration of the biomaterial to the bone matrix. PVA was combined with PVPA to provide hydrophilicity, biocompatibility and improve its spinnability. To improve its mechanical strength, PVPA/PVA and neat PVA mixtures were combined to produce a multilayer scaffold. The physical and chemical properties of the of the fabricated matrix was investigated by SEM and TEM morphological analyses, tensile strength test, XRD, FT-IR spectra, swelling behavior and biodegradation rates, porosity and contact angle measurements. Biocompatibility was also examined in vitro by cytotoxicity and cell proliferation studies with MTT assay and cell adhesion behavior by SEM and confocal microscopy.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.228-228
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• 2006

Conjugated oligomers, used as models for fluorene-thiophene copolymers, are compared in terms of the microscopic morphology of thin deposits and the optical properties. The AFM images and the solid-state absorption and emission spectra are interpreted in line with the structural data, in terms of the assembly of the conjugated molecules. The compound with a terthiophene central unit and fluorene end-groups shows well-defined monolayer-by-monolayer assembly into micrometer-long strip-like structures, with a crystalline herringbone-type organization within the monolayers. Polarized confocal microscopy indicates a strong orientation of the crystalline domains within the stripes. In contrast, the compound with a terfluorene central unit and thiophene end groups forms no textured aggregates. The difference in behavior between the two compounds most probably originates from their different capability of forming densely-packed assemblies of ${\pi-pi}$ interacting molecules. These assemblies are used as active elements in organic field effect transistors designed by using soft lithography technique.

• 한방안이비인후피부과학회지
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• 제23권2호
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• pp.57-68
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• 2010

Objective : This study was performed to evaluate the effect of Lithospermum erythrorhizon extracts on the inflammatory cytokines gene expression by the bacteria of Propionibacterium acnes (P. acnes) which elicits acne in human monocytes, THP-1 cell line. Experiment : Cytotoxicity of Lithospermum erythrorhizon extracts was analyzed by XTT assay. Real time RT-PCR was applied to analyze the cytokines gene expressions of IL-8, MCP-1 and TNF-$\alpha$. Translocation of transcription factor NF-${\kappa}B$ from cytoplasm into nucleus was observed using immunocytochemistry and confocal microscopy. Results : Lithospermum erythrorhizon extracts did not show cytotoxicity as high as in $1,000\;{\mu}g/ml$ of concentration. Transcription levels of inflammatory cytokines, IL-8, MCP-1 and TNF-$\alpha$ were increased by P. acnes in THP-1 and Lithospermum erythrorhizon extracts decreased the upregulated transcription levels. Lithospermum erythrorhizon extracts significantly inhibited the translocation of NF-${\kappa}B$ into nucleus by P. acnes. Conclusion : This study suggests that Lithospermum erythrorhizon extracts have anti-inflammatory effects on P. acnes treated THP-1 as decreasing the mRNA expressions of IL-8, MCP-1 and TNF-$\alpha$. This anti-inflammatory effect of Lithospermum erythrorhizon extracts may be useful in therapeutic treatments for acne vulgaris.

• Current Optics and Photonics
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• 제2권1호
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• pp.79-84
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• 2018

We present a novel and simple method to enable spatially selective $ZnAl_2O_4$ nanocrystal formation on the surface of $B_2O_3$-$Al_2O_3$-ZnO-CaO-$K_2O$ glass by employing localized laser heating. Optimized precipitation of glass-ceramics containing nanocrystals doped with $Eu^{3+}$ and $Yb^{3+}$ ions was performed by controlling $CO_2$ laser power and scan speed. Micro-x-ray diffraction and transmission electron microscopy revealed the mean size and morphology of nanocrystals, and energy dispersive x-ray spectroscopy showed the lateral distribution of elements in the imaged area. Laser power and scan speed controled annealing temperature for crystalization in the range of 1.4-1.8 W and 0.01-0.3 mm/s, and changed the size of nanocrystals and distribution of dopant ions. We also report more than 20 times enhanced downshift visible emission under ultraviolet excitation, and 3 times increased upconversion emission from $Eu^{3+}$ ions assisted by efficient sensitizer $Yb^{3+}$ ions in nanocrystals under 980 nm excitation. The confocal microscope revealed the depth profile of $Eu^{3+}$ ions by showing their emission intensity variation.

• IMMUNE NETWORK
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• 제10권1호
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• pp.5-14
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• 2010

Background: There have been several reports describing the capability of ginseng extracts as an adjuvant. In this study, we tested if ginsan, a polysaccharide extracted from Panax ginseng, was effective in enhancing antibody response to orally delivered Salmonella antigen. Methods: Ginsan was treated before oral salmonella antigen administration. Salmonella specific antibody was determined by ELISA. mRNA expression was determined by RT-PCR. Cell migration was determined by confocal microscopy and flow cytometry. COX expression was detected by western blot. Results: Ginsan treatment before oral Salmonella antigen delivery significantly increased both secretory and serum antibody production. Ginsan increased the expression of COX in the Peyer's patches. Various genes were screened and we found that CCL3 mRNA expression was increased in the Peyer's patch. Ginsan increased dendritic cells in the Peyer's patch and newly migrated dendritic cells were mostly found in the subepithelial dome region. When COX inhibitors were treated, the expression of CCL3 was reduced. COX inhibitor also antagonized both the migration of dendritic cells and the humoral immune response against oral Salmonella antigen. Conclusion: Ginsan effectively enhances the humoral immune response to orally delivered antigen, mediated by CCL3 via COX. Ginsan may serve as a potent vaccine suppliment for oral immunization.