Publications by authors named "Hong H Chang"

Two field experiments were conducted to improve the conception rate of Hanwoo cow. The first experiment aimed to investigate the physiological condition of Hanwoo cows on estrus, including metabolic profiles and body condition score (BCS). The second experiment investigated the effect of a novel estrus detector on the artificial insemination (AI) conception rate for Hanwoo cows.

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In this study, we investigated the effects of linoleic acid (LA) treatment on Brucella abortus infection in professional phagocyte RAW264.7 cells, particularly during the pathogens invasion and intracellular growth in these cells, as well as in murine model BALB/c mice focusing on bacterial splenic proliferation and immunoregulatory activities. LA inhibited the growth of in a doseand time-dependent manner.

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Brucella as a stealthy intracellular pathogen avoids activation of innate immune response. Here we investigated the contribution of an adenosine receptor, Adora2b, during Brucella infection in professional phagocyte RAW 264.7 cells and in a murine model.

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The cellular oncogene c-Fos (c-Fos) is a component of activator protein 1 (AP1), a master transcriptional regulator of cells. The suppression of c-Fos signaling by siRNA treatment resulted in significant induction of TLR4, which subsequently activates p38 and ERK1/2 mitogen-activated protein kinases (MAPKs) and enhances F-actin polymerization, leading to an increase in phagocytosis. During infection, c-Fos signaling is induced, which activates the downstream innate-immunity signaling cascade for bacterial clearance.

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Background: Brucella causes a chronic and debilitating infection that leads to great economic losses and a public health burden. In this study, we demonstrated the brucellacidal effect of heat shock mediated by the induction of pro-inflammatory cytokines, reactive oxygen species (ROS) accumulation and apoptosis in murine macrophages and in mice.

Results: RAW264.

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is a Gram-negative zoonotic pathogen for which there is no 100% effective vaccine. Phagosomes in -infected cells fail to mature, allowing the pathogen to survive and proliferate. Interleukin 10 (IL10) promotes persistence in macrophages by mechanisms that are not fully understood.

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Th17-cell-mediated inflammation is affected by the soluble form of common cytokine receptor γ chain (γ). We previously suggested that inflammatory cytokines including interleukin (IL)-17A are associated with Riemerella anatipestifer infection, which a harmful bacterial pathogen in ducks. Here, the expression profiles of membrane-associated γ (duγ-a) and soluble γ (duγ-b) in R.

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Lipocalin 2 (Lcn2) is an important innate immunity component against bacterial pathogens. In this study, we report that Lcn2 is induced by Brucella (B.) abortus infection and significantly contributes to the restriction of intracellular survival of Brucella in macrophages.

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In this study, we explore the regulatory roles of pro-inflammatory cytokine tumor necrosis factor alpha (TNF) in the innate immunity of macrophages against infection. We show that infection of macrophage with induces marked expression and secretion of TNF which subsequently binds to TNF receptor 1 (TNFR-1) and activates a downstream signaling cascade of the innate immunity. Blocking of TNF signaling resulted in a notable increase of survival which was associated with an increase of anti-inflammatory cytokine interleukin 10 (IL-10), a beneficial effector of survival, as well as remarkable decrease of reactive oxygen species (ROS) and nitric oxide (NO), antibrucella molecules.

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Riemerella anatipestifer, an important infectious bacterium affecting the duck industry, has 5-75% mortality, depending on strain virulence. We previously demonstrated that proinflammatory cytokines are involved in inflammation during, and regulating susceptibility to, R. anatipestifer infection.

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Brucellosis is an emerging infectious disease affecting humans and animals. In this study, we investigated the and effects of tannic acid (TA) against infection. After infection, F-actin polymerization and mitogen-activated protein kinases (MAPKs) (ERK 1/2 and p38α) phosphorylation were reduced in TA-treated cells compared with that in control cells.

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Brucellosis is one of the most important and widespread zoonosis worldwide responsible for serious economic losses and considerable public health burden. In this study, we investigated the modulatory effect of a microtubule-inhibitor, nocodazole, on B. abortus infection in murine macrophages and in a mouse model.

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Ginsenoside Rg3, a saponin extracted from ginseng, has various pharmacological and biological activities; however, its effects against infection are still unclear. Herein, the inhibitory effects of ginsenoside Rg3 against intracellular parasitic infection were evaluated through bacterial infection, adherence assays, and LAMP-1 colocalization, as well as immunoblotting and FACS for detecting MAPK signaling proteins and F-actin polymerization, respectively. The internalization, intracellular growth, and adherence of in Rg3-treated RAW 264.

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Background: Brucella abortus is an intracellular pathogen which can infect and persist in host cells through multiple interactions. Above all, its interaction to host cell receptor is important to understand the pathogenic mechanisms of B. abortus.

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To date, detection of antibodies against the lipopolysaccharide portion is the backbone of most serodiagnostic methods for brucellosis screening. However this pose a risk for false positive reactions related to other pathogens especially that of Yersinia enterocolitica O:9 which has the most prominent cross reactivity with Brucella spp. In this study, cloning and expression of Brucella abortus bacterioferritin (Bfr) was accomplished by PCR amplification into an expression vector system, and purification of a recombinant B.

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Korean red ginseng (KRG) has long been used in traditional Korean and Oriental medicine. However, the anti-bacterial mechanism and therapeutic efficiency of KGR for intracellular Brucella infection are still unclear. In this study, the bactericidal activity of Korean red ginseng acidic polysaccharide (RGAP) on Brucella (B.

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Brucellosis affects a wide range of host species, including humans and many livestock animals. Chronic infections of the disease make antibiotic treatment costly, and the current vaccine used in livestock has not been approved for human use. This study investigated the possible use of the Brucella abortus outer membrane protein A (OmpA) as a candidate subunit vaccine in an infected mouse model.

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Brucellosis is one of the major zoonoses worldwide that inflicts important health problems in animal and human. Here, we demonstrated that dextran sulfate sodium (DSS) significantly increased adhesion of Brucella (B.) abortus in murine macrophages compared to untreated cells.

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In this study, the Brucella abortus ohr gene coding for an organic hydroperoxide resistance protein (Ohr) was cloned into a maltose fusion protein expression system (pMAL), inserted into Escherichia coli, and purified, and its immunogenicity was evaluated by western blot analysis using Brucella-positive mouse sera. The purified recombinant Ohr (rOhr) was treated with adjuvant and injected intraperitoneally into BALB/c mice. A protective immune response analysis revealed that rOhr induced a significant increase in both the IgG1 and IgG2a titers, and IgG2a reached a higher level than IgG1 after the second and third immunizations.

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This study indicated that RGSF-A caused a marked reduction in the adherence, internalization and intracellular growth of Brucella abortus in RGSF-A-treated cells. Furthermore, a decline in the intensity of F-actin fluorescence was observed in RGSF-A-treated cells compared with untreated B. abortus-infected cells.

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Interleukin-17F (IL-17F) is a proinflammatory cytokine that plays an important role in gut homeostasis. A full-length duck IL-17F (duIL-17F) cDNA with a 510-bp coding region was identified in ConA-activated splenic lymphocytes. duIL-17F is predicted to encode 166 amino acids, including a 26-amino acid signal peptide, a single N-linked glycosylation site, and six cysteine residues that are conserved in mammalian IL-17.

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In this study, we particularly evaluated the protective effect of recombinant protein encoded by Brucella abortus 544 ndk (nucleoside diphosphate kinase) gene against B. abortus infection in the BALB/c mice. Cloning and expression of B.

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In this study, we characterized the secreted proteins of Brucella abortus into the enriched media under the bacterial laboratory growth condition and investigated the pathogenic importance of culture supernatant (CS) proteins to B. abortus infection. CS proteins from stationary phase were concentrated and analyzed using 2D electrophoresis.

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Both interleukin-17A (IL-17A) and IL-17F are proinflammatory cytokines that have an important role in intestinal homeostasis via receptor signaling. These cytokines have been characterized in chickens, but very little is known about their receptors and their functional activity. We provide here the first description of the sequence analysis, bioactivity, and comparative expression analysis of chicken IL-17RA (chIL-17RA) in chickens infected with Salmonella and Eimeria, two major infectious agents of gastrointestinal diseases of poultry of economic importance.

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