• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.119-134
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• 2004

Human exposure to highly nickel-polluted environments, such as those associated with nickel refining, electroplating, and welding, has the potential to produce a variety of pathologic effects. Among them are skin allergies, lung fibrosis, and cancer of the respiratory tract. The exact mechanisms of nickel-induced carcinogenesis are not known and have been the subject of numerous epidemiologic and experimental investigations. This review provides the evidence of the current state for the genotoxic and mutagenic activity of Ni (II) particularly at high doses. Such doses are best delivered into the cells by phagocytosis of sparingly soluble nickel-containing dust particles. Ni (II) genotoxicity may be aggravated through the generation of DNA-damaging reactive oxygen species (ROS) and the inhibition of DNA repair by this metal. The epigenetic effects of nickel includes alteration in gene expression resulting from DNA hypermethylation and histone hypoacetylation, as well as activation some signaling pathways and subsequent transcrziption factors.

• YAKHAK HOEJI
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• v.44 no.6
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• pp.566-571
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• 2000

We have previously observed that glycyrrhizin(GL) inhibits the proliferation of transplanted-L1210 cells via the production of nitric oxide from peritoneal macrophages. In the present study, we examined the effect of GL on Iymphocytes subpopulation change of L1210 cells-transplanted mice. GL increased the population of $CD4^-CD8^+$ cells of thymocytes in L1210 cells-transplanted mice and the lucigenin chemiluminescence of human polymorphonuclear cells. These results suggest that the proliferation of transplanted-L1210 cells is partly inhibited by an enhancement of cytotoxic T cells population and phagocytic activity in GL-administered mice.

• Animal cells and systems
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• v.11 no.2
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• pp.191-198
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• 2007

The ultrastructure of germ cells and follicle cells during oogenesis, oocyte degeneration, reproductive cycle, and first sexual maturity in female Cyclina sinensis were investigated for clams collected from Simpo, Jeollabuk-do, Korea, by cytological and histological observations. Vitellogenesis occured by way of endogeous autosynthesis and exogenous heterosynthesis: vitellogensis occurred through a process of autosynthesis, which involves a combined activities of the Golgi complex, mitochondria, and rough endoplasmic reticulum. The process of heterosynthesis involved endocytotic incorporation of extraovarian precursors into the basal region of the early vitellogenic oocytes prior to the formation of vitelline envelope. The follicle cells appear to play an integral role in vitellogenesis and oocyte degeneration, functioning in phagocytosis and digestion of products originating from the degenerated oocytes: these functions can permit the transfer of yolk precursors needed for vitellogenesis. Follicle cells might have a lysosomal system for breakdown and might also resorb phagosomes in the cytoplasm for nutrient storage during oocyte degeneration.

• Toxicological Research
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• v.11 no.2
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• pp.289-294
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• 1995

This study was designed to observe the effect of tohiene pretreatment on leukocyte variation in whole blood and the oxygen free radical generating, scavenging enzyme activities in neutrophil of bacteria infected rats. Toluene was administered 7 times intraperitoneally at levels of 9.45 mM/kg body weight to the rats and then infected with S. aureus $2\times10^7$ cfu/ml. The toluene treated-rats showed the significantly decreased numbers of lymphocyte and monocytes, but the similiar numbers of neutrophils with the control. Furthermore the increased neutrophils in blood of bacteria infected rats were reduced by the toluene pretreatment. Concomitantly the increased activities of xanthine oxidase and superoxide dismutase in neutrophil of bacteria infected rats were also decreased by the toluene pretreatment. On the other hand, injection of benzaldehyde to rats also led to similiar results in the count of leukocytes, xanthine oxidase and superoxide dismutase activities of neutrophil with those of toluene treated rats. These data suggest that toluene and its intermediate metabolite, benzaldehyde influence on the phagocytosis and defence mechanism of neutrophil.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1737-1744
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• 2012

Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine which plays roles in inflammation, immune responses and cancer development. It assists macrophages in carrying out functions like phagocytosis, adherence and motility. Of late, MIF is implicated in almost all stages of neoplasia and expression is a feature of most types of cancer. The presence of MIF in almost all tumors and all stages of cancer makes it an interesting candidate for cancer therapy. This review explores the roles of MIF in neoplasia.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.132.1-132.1
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• 2014

Fluorescent-magnetic nanoclusters were synthesized for biomedical applications. The nanoclusters consisted of superparamagnetic core-nanoclusters, highly fluorescent shell of nanocrystals, and lipid A. Magnetic cores were used for both magnetic resonance imaging (MRI) and cell separation. Fluorescent shell was used for optical imaging. The lipid-A-loaded nanoclusters were up-taken by dendritic cells via phagocytosis, which successfully activated dendritic cells. The dendritic cells were migrated to lymph nodes and spleen of mice. The results showed that our novel nanoclusters can play a role as an efficient optical and magnetic imaging, a cell separating and a pathogen mimetic agent at the same time. Additionally, synthesis of wavelength conversion nanowires will be discussed, which may be used as an optical nanoprobe in biological studies.

• The Korean Journal of Food And Nutrition
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• v.14 no.2
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• pp.99-105
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• 2001

Immunoregulative action of 70% ethyl alcohol fraction of Cervus nippon was investigated in vitro. The fraction enhanced the proliferation of thymocytes and the population of CD4$\^$+/CD8$\^$-/ single-positive cells in thymocytes. CN-E enhanced [Ca$\^$2+]$\sub$i/, the production of TNF-${\alpha}$ and IL-1 ${\beta}$, and phagocytosis in peritoneal macrophages. The fraction did not induce the proliferation of splenocytes and DNA fragmentation in thymocytes. These results indicate that 70% ethyl alcohol fraction of Cervus nippon regulates immunological action by stimulating murine thymocytes and macrophages.

• Advances in Traditional Medicine
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• v.4 no.1
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• pp.9-17
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• 2004

The present investigation was under taken to study whether the tumor-associated macrophages (TAM) of Daltons lymphoma (DL), a spontaneous transplantable murine T cell lymphoma can be activated to tumoricidal state by crude thymus extract. Intraperitoneal administration of thymus extract to DL-bearing mice resulted in activation of TAM with an enhanced IL-1, TNF and antigen presenting ability. It was found that treatment with thymus extract could also enhance the phagocytic and cytotoxic activity of TAM. However, only a marginal increase in arginase activity was observed. Till date to the best of our knowledge the effect of crude thymus extract on the activation of tumor associated macrophages has not been investigated, this study provides a new piece of information in the area of thymus therapy.

• The Korean Journal of Zoology
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• v.22 no.2
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• pp.67-81
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• 1979

Eelctron microscopic cytochemical methods reveal that acid phosphatase activity appears exclusively in vacuoles surrounding established symbiotes. However, copius amounts of acid phosphatase reaction product are visible between and around some of the degenerating symbiotes in the amebae after treatment of chloramphenicol. It is thought that bacteriostasis by chloramphenicol has served to lost the symbiotic interference to intracellular digestion by the ameba and possibly phodphatase enxymes have been implicated in phagocytosis and intracellular digestion of the symbiotic bacteria.

• Molecules and Cells
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• v.40 no.3
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• pp.163-168
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• 2017

Microglia are the primary resident immune cells of the central nervous system (CNS). They are the first line of defense of the brain's innate immune response against infection, injury, and diseases. Microglia respond to extracellular signals and engulf unwanted neuronal debris by phagocytosis, thereby maintaining normal cellular homeostasis in the CNS. Pathological stimuli such as neuronal injury induce transformation and activation of resting microglia with ramified morphology into a motile amoeboid form and activated microglia chemotax toward lesion site. This review outlines the current research on microglial activation and chemotaxis.