• Proceedings of the National Institute of Ecology of the Republic of Korea
• /
• v.3 no.2
• /
• pp.73-76
• /
• 2022

Most of ants seem to be beneficial, whereas some of them are annoying or harmful. Among harmful creatures red imported fire ants have been notorious for not only destroying farm plants and domestic animals but also biting and killing human beings. The red imported fire ants, Solenopsis invicta Buren and Solenopsis richiteri Forel, will feed on the buds and fruits of numerous crop plants. Large nests located in fields interfere with and damage equipment during cultivation and harvesting. They respond rapidly and aggressively to disturbances, and ant attacks inhibit field worker activities. A single fire can sting its target repeatedly. Young and newborn animals as well as humans are especially susceptible to the stings' venom. These pests can damage the environment by displacing native ant species and reducing food sources for wildlife. In Korea Solenopsis invicta Buren were found for the first time in Busan Gamman port in 2017. Then they were found in Incheon port, Pyongtaek port, North Daegu, Ansan in 2018 and Gwangyang in 2021. Once they invaded and occupied the terrestrial area, we have no proper solution to prevent them. I can assume that they have been successfully enlarging their colonies toward inland since they can move freely by flight. Therefore, I strongly suggest that we need to study ants in order not only to control harmful ants properly but also to preserve and use beneficial ants in this country.

• Journal of the Chungcheong Mathematical Society
• /
• v.23 no.4
• /
• pp.813-821
• /
• 2010

Let G and H be compact connected Lie groups with biinvariant Riemannian metrics g and h respectively, ${\phi}$ a group isomorphism of G onto H, and $E:={\phi}^{-1}TH$ the induced bundle by $\phi$ over the base manifold G of the tangent bundle TH of H. Let ${\nabla}$ and $^H{\nabla}$ be the Levi-Civita connections for the metrics g and h respectively, $\tilde{\nabla}$ the induced connection by the map ${\phi}$ and $^H{\nabla}$. Then, a necessary and sufficient condition for $\tilde{\nabla}$ in the bundle (${\phi}^{-1}TH$, G, ${\pi}$) to be a Yang- Mills connection is the fact that the Levi-Civita connection ${\nabla}$ in the tangent bundle over (G, g) is a Yang- Mills connection. As an application, we get the following: Let ${\psi}$ be an automorphism of a compact connected semisimple Lie group G with the canonical metric g (the metric which is induced by the Killing form of the Lie algebra of G), ${\nabla}$ the Levi-Civita connection for g. Then, the induced connection $\tilde{\nabla}$, by ${\psi}$ and ${\nabla}$, is a Yang-Mills connection in the bundle (${\phi}^{-1}TH$, G, ${\pi}$) over the base manifold (G, g).

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.4
• /
• pp.423-428
• /
• 2022

This paper deals with whether it is possible to find a way to solve the conflict between villagers and tourists by newly defining the difference between free village and public tourist destinations in Korea, reinforce the insufficient guidance and notification services with realistic media, and implement additional killing contents and attractions. Location-based service enables real-time docent service and emergency response and smart glass thread.

• Biomedical Science Letters
• /
• v.29 no.3
• /
• pp.178-183
• /
• 2023

Natural killer (NK) cells are innate cytotoxic lymphoid cells that actively prevent neoplastic development, growth, and metastatic dissemination in a process called cancer immunosurveillance. Regulation of the cytotoxic activity of NK cells relies on integrated interactions between inhibitory receptors and numerous activating receptors that act in tandem to eliminate tumor cells efficiently. Conventional chemotherapy is designed to produce an anti-proliferative or cytotoxic effect on early tumor cell division. Therapies designed to kill cancer cells and simultaneously maintain host anti-tumor immunity are attractive strategies for controlling tumor growth. Depending on the drug and dose used, several chemotherapeutic agents cause DNA damage and cancer cell death through apoptosis, immunogenic cell death, or other forms of non-killing (i.e., mitotic catastrophe, senescence, autophagy). Among stress-induced immunostimulatory proteins, changes in the expression levels of NK cell activating and inhibitory ligands and tumor cell death receptors play an important role in the detection and elimination by innate immune effectors including NK cells. Therefore, we will address how these cytotoxic lymphocytes sense and respond to high and low concentrations of drug-induced stress to the drug cisplatin, among the various types of drugs that contribute to their anticancer activity.

• Journal of fish pathology
• /
• v.37 no.1
• /
• pp.89-96
• /
• 2024

Kudoa septempunctata, a myxozoan parasite, usually presents without any signs and primarily infects adult fish. The invasive diagnostic methods, such as tissue biopsy, can identify pathogens, but cause economic losses because they require killing the fish. In this study, we conducted a monitoring of four fish farms located on Jeju Island, to investigate the potential for non-invasive diagnosis of K. septempunctata using hyperspectral cameras. It provides spectral information from R000_B000_G000 to R255_B255_G255 for a total of 3,282 olive flounder (Paralichthys olivaceus). Each object is imaged with 2,000 data points, allowing comprehensive spectral analysis by comparing images obtained from negative control objects to positive control objects. Noticeable differences were observed in the brightness or pallor of the positive control images. This suggests the potential utility of hyperspectral imaging as a non-invasive diagnostic tool for detecting K. septempunctata infections in fish populations.

• IMMUNE NETWORK
• /
• v.22 no.5
• /
• pp.38.1-38.24
• /
• 2022

Exosomes, which are well-known nanoscale extracellular vesicles, are multifunctional biomaterials derived from endosomes and perform various functions. The exosome is a critical material in cell-cell communication. In addition, it regulates the pathophysiological conditions of the tumor microenvironment in particular. In the tumor microenvironment, exosomes play a controversial role in supporting or killing cancer by conveying biomaterials derived from parent cells. Innate immunity is a crucial component of the host defense mechanism, as it prevents foreign substances, such as viruses and other microbes and tumorigenesis from invading the body. Early in the tumorigenesis process, the innate immunity explicitly recognizes the tumor via Ags and educates the adaptive immunity to eliminate it. Recent studies have revealed that exosomes regulate immunity in the tumor microenvironment. Tumor-derived exosomes regulate immunity against tumor progression and metastasis. Furthermore, tumor-derived exosomes regulate polarization, differentiation, proliferation, and activation of innate immune cells. Exosomes produced from innate immune cells can inhibit or support tumor progression and metastasis via immune cell activation and direct cancer inhibition. In this study, we investigated current knowledge regarding the communication between tumor-derived exosomes and innate immune cell-derived exosomes (from macrophages, dendritic cells, NK cells, and neutrophils) in the tumor microenvironment. In addition, we discussed the potential development of exosomal immunotherapy using native or engineered exosomes against cancer.

• Journal of Dairy Science and Biotechnology
• /
• v.42 no.2
• /
• pp.35-47
• /
• 2024

Milk exosomes contain several bioactive molecules, including lipids, proteins, and miRNAs, which enhance immune response. This study aimed to assess the resistance effects of bovine colostrum exosomes (BCEs) on pathogenic microbial infections in a Caenorhabditis elegans model. BCEs have been shown to enhance the protective response of C. elegans to pathogenic bacterial infections. Our study revealed that BCE extended the lifespan of worms compared to control OP50 worms. In addition, nematode colostrum exosomes promoted nematode resistance to four pathogenic bacteria and prolonged their lifespan in a killing assay. In contrast, mature milk-derived exosomes (BME) did not affect the resistance and lifespan of nematodes exposed to pathogenic bacteria. BCE exposure extended the lifespan of C. elegans against pathogenic infections by stimulating the innate immune response and increasing antimicrobial protein expression. Using biological process-related gene ontology (GO) enrichment analysis, the significantly upregulated GO terms related to C. elegans immunity in BCE-exposed C. elegans included defense, innate immunity, and immune responses. This study demonstrated that BCE enhanced the host defense of C. elegans to prolong its lifespan, thereby suggesting a new natural product against infection by pathogenic bacteria.

• Archives of Pharmacal Research
• /
• v.16 no.1
• /
• pp.36-42
• /
• 1993

To find biologically active components of the higher fungi of Korea, the carpophores of Auricularia polytricha, a well-known edible mushroom, were extracted with 0.14 M NaCl solution. The extract was successively fractionated by adding ammonium sulfate at various concentrations, and the respective precipitates were separated by centrifugation, then dialyzed and freeze-dried. When a does of 60 mg/kg of each was injected i.p. into ICR mice, the fraction which precipitated at 20% ammonium sulfate showed the highest toxicity, killing seven out of seven mice within two days. The fraction obtained at 40% ammonium sulfate showed the second highest toxicity. The two fractions were named auritoxin I and II after the genus name. However, they Nere shown to have nearly identical composition by physicochemical and 6.8% protein. The polysaccharide moiety was found to have 12.3% $\alpha$-linkage and 87.7% $\beta$-linkage and to be a heteromannoglucan consisting of 45.1% glucose, 435 mannose and 11.0% xylose. The protein moiety contained ten amino adids. The molecular weight of the toxin was $1.5\times10^6$ dalton by Sepharose CL-4B gel filtration. The modian lethal doses of auritoxin in mice were 56.4, 157.2 and 454.6 mg/kg by i.p., s.c. and p.o.administrations, respectively. The signs of intrxication were convulsion during the first 30 minutes after the injection, coma or sleeping within an hour, termor, lacrimation, nasal bleeding congestion, and death in 24 hours. Smong the various organs, the spleen was found to be enlarged remarkably. Human platelet aggregation was inhibited by the addition of auritoxin. The activity of malic dehydrogenase in vitro was inhibited by the toxin.

• Journal of Photoscience
• /
• v.9 no.2
• /
• pp.479-481
• /
• 2002

UV-induced DNA damage causes cell killing and mutations leading to carcinogenesis. In normal human cells, UV damage such as cyclobutane pyrimidine dimers (CPDs) and primidine-prymidone (6-4) photoproducts are mainly repaired by nucleotide excision repair mechanism. The molecular processes have been well characterized recently. To know the influence of mitochondrial genome on the nucleotide excision repair mechanism against CPDs, we comparatively examined the production of CPDs by UVC irradiation and their repair kinetics in human cells completely lacking mitochondrial DNA (mtDNA) and the parental HeLa S cells. Whole DNA extracted from the cells exposed to UVC was treated with T4-endonuclease V to break the phosphodiester bond adjacent to CPDs. The DNA was electrophoresed in a denaturing agarose gel, which was visualized by ethidium bromide staining. The relative amount of CPDs was determined by image analysis using NIH Image software. MtDNA- less (rho-O) cells were apparently more sensitive to UVC than HeLa S cells, while the level of induction of CPDs in rho-O and HeLa cells was comparable. The repair of CPDs was less efficient in rho-O cells compared with HeLa cells. The residual amount of CPDs after 24-h repair was larger in rho-O cells than in HeLa cells where more than 90 % of CPDs were repaired by then. The non-repaired CPDs would lead to apoptosis in rho-O cells. These results suggest that mitochondrial genome may contribute to some ATP-dependent steps in nucletide excision repair by supplying sufficient ATP which is generated through a respiratory chain in mitochondria.

• Food Science and Biotechnology
• /
• v.14 no.4
• /
• pp.479-486
• /
• 2005

Arabinoxylan, a complex polysaccharide in cereal cell walls, has recently received research attention as a biological response modifier. The immunomodulating effect of arabinoxylans from rice bran (AXrb) was studied using a combined process of extrusion and commercial hemicellulase treatment in order to elucidate the augmentation mechanism of cell-mediated immunity in vitro. The cytotoxicity of mouse spleen lymphocytes against YAC-1 tumor cells was significantly enhanced by treatment with AXrb at $10-100\;{\mu}g/mL$. In an attempt to investigate the mechanism by which AXrb enhance NK cytotoxicity, we examined the effect of AXrb on cytokine production by spleen lymphocytes. Culture supernatants of the cells incubated with AXrb were collected and analyzed for IL-2 and IFN-${\gamma}$ synthesis by ELISA. IL-2 and IFN-${\gamma}$ production were increased significantly. These results suggest that AXrb may induce Th1 immune responses. Macrophages play an important role in host defenses against tumors by killing them and producing secretory products, which protect against bacterial, viral infection and malignant cell growth. AXrb were examined for their ability to induce secretory and cellular responses in murine peritoneal macrophages. When macrophages were treated with various concentrations ($10-100\;{\mu}g/mL$) of AXrb, AXrb induced tumoricidal activity, as well as increasing phagocytosis and the production of NO, $H_2O_2$, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. These results indicate that reactive oxygen species, reactive nitrogen species, and inflammatory cytokines are likely to be the major mediators of tumoricidal activity in AXrb-treated macrophages. Therefore, AXrb may be useful in cancer immunotherapy and it is anticipated that AXrb obtained using extrusion and subsequent enzyme treatment can be used as an ingredient in nutraceuticals and cereal-based functional food.